Science.gov

Sample records for control diverse aspects

  1. Aspects of Diversity Measurement for Microbial Communities

    PubMed Central

    Mills, Aaron L.; Wassel, Raymond A.

    1980-01-01

    A useful measure of diversity was calculated for microbial communities collected from lake water and sediment samples using the Shannon index (H?) and rarefaction [E(S)]. Isolates were clustered by a numerical taxonomy approach in which limited (<20) tests were used so that the groups obtained represented a level of resolution other than species. The numerical value of diversity for each sample was affected by the number of tests used; however, the relative diversity compared among several sampling locations was the same whether 11 or 19 characters were examined. The number of isolates (i.e., sample size) strongly influenced the value of H? so that unequal sized samples could not be compared. Rarefaction accounts for differences in sample size inherently so that such comparisons are made simple. Due to the type of sampling carried out by microbiologists, H? is estimated and not determined and therefore requires a statement of error associated with it. Failure to report error provided potentially misleading results. Calculation of the variance of H? is not a simple matter and may be impossible when handling a large number of samples. With rarefaction, the variance of E(S) is readily determined, facilitating the comparison of many samples. PMID:16345636

  2. Fibrinogen-Related Proteins in Tissue Repair: How a Unique Domain with a Common Structure Controls Diverse Aspects of Wound Healing

    PubMed Central

    Zuliani-Alvarez, Lorena; Midwood, Kim S.

    2015-01-01

    Significance: Fibrinogen-related proteins (FRePs) comprise an intriguing collection of extracellular molecules, each containing a conserved fibrinogen-like globe (FBG). This group includes the eponymous fibrinogen as well as the tenascin, angiopoietin, and ficolin families. Many of these proteins are upregulated during tissue repair and exhibit diverse roles during wound healing. Recent Advances: An increasing body of evidence highlights the specific expression of a number of FRePs following tissue injury and infection. Upon induction, each FReP uses its FBG domain to mediate quite distinct effects that contribute to different stages of tissue repair, such as driving coagulation, pathogen detection, inflammation, angiogenesis, and tissue remodeling. Critical Issues: Despite a high degree of homology among FRePs, each contains unique sequences that enable their diversification of function. Comparative analysis of the structure and function of FRePs and precise mapping of regions that interact with a variety of ligands has started to reveal the underlying molecular mechanisms by which these proteins play very different roles using their common domain. Future Directions: Fibrinogen has long been used in the clinic as a synthetic matrix serving as a scaffold or a delivery system to aid tissue repair. Novel therapeutic strategies are now emerging that harness the use of other FRePs to improve wound healing outcomes. As we learn more about the underlying mechanisms by which each FReP contributes to the repair response, specific blockade, or indeed potentiation, of their function offers real potential to enable regulation of distinct processes during pathological wound healing. PMID:26005593

  3. Informational Aspects of Isotopic Diversity in Biology and Medicine

    NASA Astrophysics Data System (ADS)

    Berezin, Alexander A.

    2004-10-01

    Use of stable and radioactive isotopes in biology and medicine is intensive, yet informational aspects of isotopes as such are largely neglected (A.A.Berezin, J.Theor.Biol.,1992). Classical distinguishability (``labelability'') of isotopes allows for pattern generation dynamics. Quantum mechanically advantages of isotopicity (diversity of stable isotopes) arise from (almost perfect) degeneracy of various isotopic configurations; this in turn allows for isotopic sweeps (hoppings) by resonance neutron tunneling (Eccles mechanism). Isotopic variations of de Broglie wavelength affect quantum tunneling, diffusivity, magnetic interactions (e.g. by Lorentz force), etc. Ergodicity principle (all isoenergetic states are eventually accessed) implies possibility of fast scanning of library of morphogenetic patterns (cf metaphors of universal ``Platonic'' Library of Patterns: e.g. J.L.Borges, R.Sheldrake) with subsequent Darwinian reinforcement (e.g. by targeted mutations) of evolutionary advantageous patterns and structures. Isotopic shifts in organisms, from viruses and protozoa to mammalians, (e.g. DNA with enriched or depleted C-13) are tools to elucidate possible informational (e.g. Shannon entropy) role of isotopicity in genetic (e.g. evolutionary and morphological), dynamical (e.g. physiological and neurological) as well as medical (e.g. carcinogenesis, aging) aspects of biology and medicine.

  4. Novel aspects of plasma control in ITER

    SciTech Connect

    Humphreys, D.; Jackson, G.; Walker, M.; Welander, A.; Ambrosino, G.; Pironti, A.; Felici, F.; Kallenbach, A.; Raupp, G.; Treutterer, W.; Kolemen, E.; Lister, J.; Sauter, O.; Moreau, D.; Schuster, E.

    2015-02-15

    ITER plasma control design solutions and performance requirements are strongly driven by its nuclear mission, aggressive commissioning constraints, and limited number of operational discharges. In addition, high plasma energy content, heat fluxes, neutron fluxes, and very long pulse operation place novel demands on control performance in many areas ranging from plasma boundary and divertor regulation to plasma kinetics and stability control. Both commissioning and experimental operations schedules provide limited time for tuning of control algorithms relative to operating devices. Although many aspects of the control solutions required by ITER have been well-demonstrated in present devices and even designed satisfactorily for ITER application, many elements unique to ITER including various crucial integration issues are presently under development. We describe selected novel aspects of plasma control in ITER, identifying unique parts of the control problem and highlighting some key areas of research remaining. Novel control areas described include control physics understanding (e.g., current profile regulation, tearing mode (TM) suppression), control mathematics (e.g., algorithmic and simulation approaches to high confidence robust performance), and integration solutions (e.g., methods for management of highly subscribed control resources). We identify unique aspects of the ITER TM suppression scheme, which will pulse gyrotrons to drive current within a magnetic island, and turn the drive off following suppression in order to minimize use of auxiliary power and maximize fusion gain. The potential role of active current profile control and approaches to design in ITER are discussed. Issues and approaches to fault handling algorithms are described, along with novel aspects of actuator sharing in ITER.

  5. Novel aspects of plasma control in ITER

    NASA Astrophysics Data System (ADS)

    Humphreys, D.; Ambrosino, G.; de Vries, P.; Felici, F.; Kim, S. H.; Jackson, G.; Kallenbach, A.; Kolemen, E.; Lister, J.; Moreau, D.; Pironti, A.; Raupp, G.; Sauter, O.; Schuster, E.; Snipes, J.; Treutterer, W.; Walker, M.; Welander, A.; Winter, A.; Zabeo, L.

    2015-02-01

    ITER plasma control design solutions and performance requirements are strongly driven by its nuclear mission, aggressive commissioning constraints, and limited number of operational discharges. In addition, high plasma energy content, heat fluxes, neutron fluxes, and very long pulse operation place novel demands on control performance in many areas ranging from plasma boundary and divertor regulation to plasma kinetics and stability control. Both commissioning and experimental operations schedules provide limited time for tuning of control algorithms relative to operating devices. Although many aspects of the control solutions required by ITER have been well-demonstrated in present devices and even designed satisfactorily for ITER application, many elements unique to ITER including various crucial integration issues are presently under development. We describe selected novel aspects of plasma control in ITER, identifying unique parts of the control problem and highlighting some key areas of research remaining. Novel control areas described include control physics understanding (e.g., current profile regulation, tearing mode (TM) suppression), control mathematics (e.g., algorithmic and simulation approaches to high confidence robust performance), and integration solutions (e.g., methods for management of highly subscribed control resources). We identify unique aspects of the ITER TM suppression scheme, which will pulse gyrotrons to drive current within a magnetic island, and turn the drive off following suppression in order to minimize use of auxiliary power and maximize fusion gain. The potential role of active current profile control and approaches to design in ITER are discussed. Issues and approaches to fault handling algorithms are described, along with novel aspects of actuator sharing in ITER.

  6. Circulation control STOL aircraft design aspects

    NASA Technical Reports Server (NTRS)

    Loth, John L.

    1987-01-01

    Since Davidson patented Circulation Control Airfoils in 1960, there have been only 2 aircraft designed and flown with circulation control (CC). Designing with CC is complex for the following reasons: the relation between lift increase and blowing momentum is nonlinear; for good cruise performance one must change the wing geometry in flight from a round to a sharp trailing edge. The bleed air from the propulsion engines or an auxiliary compressor, must be used efficiently. In designing with CC, the propulsion and control aspects are just as important as aerodynamics. These design aspects were examined and linearized equations are presented in order to facilitate a preliminary analysis of the performance potential of CC. The thrust and lift requirements for takeoff make the calculated runway length very sensitive to the bleed air ratio. Thrust vectoring improves performance and can offset nose down pitching moments. The choice of blowing jet to free stream velocity ratio determines the efficiency of applying bleed air power.

  7. Novel Aspects of Plasma Control in ITER

    NASA Astrophysics Data System (ADS)

    Humphreys, D. A.; Walker, M. L.; Ambrosino, G.; Lister, J.; Treutterer, W.; Snipes, J.; Winter, A.

    2013-10-01

    ITER will place uniquely high demands on performance and reliability of plasma control, yet with constrained actuators and limited opportunity to tune algorithms. For example, divertor and core radiation must be regulated to minimize target heat flux. Plasma burn state must be controlled to achieve the Q = 10 mission and minimize disruptivity. Performance-limiting instabilities such as tearing modes must be robustly stabilized through regulation of current profile characteristics, control of sawteeth and error fields, or active ECCD suppression. Satisfying these and other control goals requires advances in both physics understanding and model-based control mathematics solutions. For example, control of proximity to tearing limits requires improved understanding of resistive stability physics to identify key profile control parameters and produce models for control design. Ensuring robust control performance relies on advances in model-based algorithm design. We describe selected plasma control challenges for ITER, highlighting novel aspects and needs for improved understanding in both physics and control mathematics. Supported in part by 4000112126 with UT Battelle, LLC under US Department of Energy DE-AC05-00OR22725.

  8. Geographic and climatic control of primate diversity.

    PubMed Central

    Reed, K E; Fleagle, J G

    1995-01-01

    Although the comparative ecology of primates has been relatively well studied and there have been a number of outstanding studies of individual primate communities, the factors determining primate species diversity on either a local or regional level are largely unexplored. Understanding the determinants of species abundance is an important aspect of biodiversity and is critical for interpreting the comparative ecology of these different communities and for designing effective strategies of conservation. Comparative analysis of species diversity in more than 70 primate communities from South America, Africa, Madagascar, and Asia shows that on major continental areas and large tropical islands, there is a high positive correlation between the number of primate species and the area of tropical forest. Within major continental areas, the species diversity at individual sites is highly correlated with mean annual rainfall for South America, Africa, and Madagascar, but not Asia. PMID:7644506

  9. High aspect ratio, remote controlled pumping assembly

    DOEpatents

    Brown, S.B.; Milanovich, F.P.

    1995-11-14

    A miniature dual syringe-type pump assembly is described which has a high aspect ratio and which is remotely controlled, for use such as in a small diameter penetrometer cone or well packer used in water contamination applications. The pump assembly may be used to supply and remove a reagent to a water contamination sensor, for example, and includes a motor, gearhead and motor encoder assembly for turning a drive screw for an actuator which provides pushing on one syringe and pulling on the other syringe for injecting new reagent and withdrawing used reagent from an associated sensor. 4 figs.

  10. High aspect ratio, remote controlled pumping assembly

    DOEpatents

    Brown, Steve B. (Livermore, CA); Milanovich, Fred P. (Lafayette, CA)

    1995-01-01

    A miniature dual syringe-type pump assembly which has a high aspect ratio and which is remotely controlled, for use such as in a small diameter penetrometer cone or well packer used in water contamination applications. The pump assembly may be used to supply and remove a reagent to a water contamination sensor, for example, and includes a motor, gearhead and motor encoder assembly for turning a drive screw for an actuator which provides pushing on one syringe and pulling on the other syringe for injecting new reagent and withdrawing used reagent from an associated sensor.

  11. Functional regularity: a neglected aspect of functional diversity.

    PubMed

    Mouillot, David; Mason, W H Norman; Dumay, Olivier; Wilson, J Bastow

    2005-01-01

    Functional diversity has been identified as a key to understanding ecosystem and community functioning. However, due to the lack of a sound definition its nature and measurement are still poorly understood. In the same way that species diversity can be split into species richness and species evenness, so functional diversity can be split into functional richness (i.e. the amount of functional trait/character/attribute space filled) and functional evenness (i.e. the evenness of abundance distribution in functional trait space). We propose a functional regularity index (FRO) as a measure of functional evenness for situations where species are represented only by a single functional trait value (e.g. mean, median or mode), and species abundances are known. This new index is based on the Bulla O index of species evenness. When dealing with functional types or categorical functional traits, the Bulla O or any other accepted species evenness index may be used directly to measure functional evenness. The advantage of FRO is that it supplies a measure of functional evenness for continuous trait data. The FRO index presented in this paper fulfils all the a priori criteria required. We demonstrate with two example datasets that a range of FRO values may be obtained for both plant and animal communities. Moreover, FRO was strongly related to ecosystem function as seen in photosynthetic biomass in plant communities, and was able to differentiate sampling stations in a lagoon based on the functional traits of fish. Thus, the FRO index is potentially a highly useful tool for measuring functional diversity in a variety of ecological situations. PMID:15655690

  12. Resource availability controls fungal diversity across a plant diversity gradient.

    PubMed

    Waldrop, Mark P; Zak, Donald R; Blackwood, Christopher B; Curtis, Casey D; Tilman, David

    2006-10-01

    Despite decades of research, the ecological determinants of microbial diversity remain poorly understood. Here, we test two alternative hypotheses concerning the factors regulating fungal diversity in soil. The first states that higher levels of plant detritus production increase the supply of limiting resources (i.e. organic substrates) thereby increasing fungal diversity. Alternatively, greater plant diversity increases the range of organic substrates entering soil, thereby increasing the number of niches to be filled by a greater array of heterotrophic fungi. These two hypotheses were simultaneously examined in experimental plant communities consisting of one to 16 species that have been maintained for a decade. We used ribosomal intergenic spacer analysis (RISA), in combination with cloning and sequencing, to quantify fungal community composition and diversity within the experimental plant communities. We used soil microbial biomass as a temporally integrated measure of resource supply. Plant diversity was unrelated to fungal diversity, but fungal diversity was a unimodal function of resource supply. Canonical correspondence analysis (CCA) indicated that plant diversity showed a relationship to fungal community composition, although the occurrence of RISA bands and operational taxonomic units (OTUs) did not differ among the treatments. The relationship between fungal diversity and resource availability parallels similar relationships reported for grasslands, tropical forests, coral reefs, and other biotic communities, strongly suggesting that the same underlying mechanisms determine the diversity of organisms at multiple scales. PMID:16972876

  13. Manual control aspects of orbital flight

    NASA Technical Reports Server (NTRS)

    Brody, Adam R.

    1990-01-01

    Studies of spacecraft rendezvous and docking operations began in the Gemini program in preparation for the two dockings required to send a crew to the moon and return them safely to Earth. However, the goal of getting to the moon before the end of the decade was of greater concern than mission optimization so little or no time or money was expended in researching human factors implications of operational aspects such as braking gates or control modes. Also, with sixteen operational dockings over a six year period (12 Apollo, 3 Skylab, and 1 ASTP) in the United States space program, economies of scale were not yet available to justify extensive research into decreasing the time or fuel necessary for a successful docking. With an operational space station era approaching in which orbital maneuvering vehicle (OMV), orbital transfer vehicle (OTV), shuttle orbiter, and other traffic will play a major role, a concerted research effort now could help avoid many potential problems later in addition to increasing safety, fuel economy, and productivity. A knowledge of manual control capabilities associated with piloted spaceflight could help save a life if the operational flight envelope can be safely enlarged to include faster dockings that currently envisioned. For example, current and future research is designed to acquire the appropriate information.

  14. On aspects of burn/profile control

    SciTech Connect

    Miley, G.H.; Varadarajan, V.

    1991-12-31

    Distributed parameter system can be flexibly turned into lumped parameter system. Multiple control objectives such as profile and power control requirements can be simultaneously modeled. Profile control is essential to control the sawteeth inversion radius and optimum power production. In this paper, a simple self-tuning control scheme is used to analyze the tokamak control behavior. The model uncertainties can be accommodated in self-tuning systems.

  15. On aspects of burn/profile control

    SciTech Connect

    Miley, G.H.; Varadarajan, V.

    1991-01-01

    Distributed parameter system can be flexibly turned into lumped parameter system. Multiple control objectives such as profile and power control requirements can be simultaneously modeled. Profile control is essential to control the sawteeth inversion radius and optimum power production. In this paper, a simple self-tuning control scheme is used to analyze the tokamak control behavior. The model uncertainties can be accommodated in self-tuning systems.

  16. Guidelines on ergonomic aspects of control rooms

    NASA Technical Reports Server (NTRS)

    Mitchell, C. M.; Bocast, A. K.; Stewart, L. J.

    1983-01-01

    The anthropometry, workstation design, and environmental design of control rooms are outlined. The automated interface and VDTs and displays and various modes of communication between the system and the human operator using VDTs are discussed. The man in the loop is examined, the single controller single task framework and multiple controller multiple tasks issues are considered.

  17. Human factors aspects of control room design

    NASA Technical Reports Server (NTRS)

    Jenkins, J. P.

    1983-01-01

    A plan for the design and analysis of a multistation control room is reviewed. It is found that acceptance of the computer based information system by the uses in the control room is mandatory for mission and system success. Criteria to improve computer/user interface include: match of system input/output with user; reliability, compatibility and maintainability; easy to learn and little training needed; self descriptive system; system under user control; transparent language, format and organization; corresponds to user expectations; adaptable to user experience level; fault tolerant; dialog capability user communications needs reflected in flexibility, complexity, power and information load; integrated system; and documentation.

  18. Ethical aspects of malaria control and research.

    PubMed

    Jamrozik, Euzebiusz; de la Fuente-Núñez, Vânia; Reis, Andreas; Ringwald, Pascal; Selgelid, Michael J

    2015-01-01

    Malaria currently causes more harm to human beings than any other parasitic disease, and disproportionally affects low-income populations. The ethical issues raised by efforts to control or eliminate malaria have received little explicit analysis, in comparison with other major diseases of poverty. While some ethical issues associated with malaria are similar to those that have been the subject of debate in the context of other infectious diseases, malaria also raises distinct ethical issues in virtue of its unique history, epidemiology, and biology. This paper provides preliminary ethical analyses of the especially salient issues of: (i) global health justice, (ii) universal access to malaria control initiatives, (iii) multidrug resistance, including artemisinin-based combination therapy (ACT) resistance, (iv) mandatory screening, (v) mass drug administration, (vi) benefits and risks of primaquine, and (vii) malaria in the context of blood donation and transfusion. Several ethical issues are also raised by past, present and future malaria research initiatives, in particular: (i) controlled infection studies, (ii) human landing catches, (iii) transmission-blocking vaccines, and (iv) genetically-modified mosquitoes. This article maps the terrain of these major ethical issues surrounding malaria control and elimination. Its objective is to motivate further research and discussion of ethical issues associated with malaria--and to assist health workers, researchers, and policy makers in pursuit of ethically sound malaria control practice and policy. PMID:26693920

  19. Manual Control Aspects of Orbital Flight

    NASA Technical Reports Server (NTRS)

    Brody, Adam R. (Editor); Ellis, Stephen R. (Editor)

    1990-01-01

    A brief description of several laboratories' current research in the general area of manual control of orbital flight is presented. With an operational-space-station era (and its increased traffic levels) approaching, now is an opportune time to investigate issues such as docking and rendezvous profiles and course-planning aids. The tremendous increase in the capabilities of computers and computer graphics has made extensive study possible and economical. It is time to study these areas, from a human factors and manual control perspective in order to preclude the occurrence of problems analogous to those that occurred in the airline and other related industries.

  20. [Ethical aspects of tuberculosis control under fascism].

    PubMed

    Hahn, S

    1983-05-01

    At the instance of the development of the tuberculosis control in the period from 1933 to 1945 is tried to elaborate the ethical principles which are the basis of the medical care of the German population in fascist Germany. The utilitaristic and biologistic opinions of the value dominating at this time proved as altogether characterized by the social aims of fascism and at the same time serve for their realization in the field of health politics. Also in the tuberculosis control--like in other social fields--transitory progress in organisation and prophylaxis and finally to be paid with deranging setbacks which reveal the inhumanity of fascism also in this field. PMID:6880311

  1. Placebo controls: historical, methodological and general aspects

    PubMed Central

    Walach, Harald

    2011-01-01

    Control conditions were introduced through the trial of Mesmerism in Paris. Placebo controls became codified standard in 1946. Although seemingly unchallenged, there are various problems with this received view. The notion of a placebo is only defined from the negative. A positive notion proposed that placebo effects are effects owing to the meaning an intervention has for an individual. Thus, placebo effects are individualized, whereas standard research paradigms reveal only grossly averaged behaviour. Also, placebo effects are context sensitive, dependent on psychological factors such as expectancy, relief of stress and anxiety, and hence can generate strong and long-lasting treatment effects. These, however, are not predictable. Such a situation can lead to the efficacy paradox: sometimes, sham interventions can be more powerful than proved, evidence-based treatments. This situation has methodological consequences. Placebo-controlled randomized trials reveal only part of the answer, whether an intervention is effective. This is valuable information for regulators, but not necessarily also for patients and of limited value for providers. Hence, I have argued that we need to complement the hierarchical model of evidence by a circular one, in which various methods are employed on equal footing to answer different questions. PMID:21576144

  2. Subjective Aspects of Cognitive Control at Different Stages of Processing

    PubMed Central

    Morsella, Ezequiel; Wilson, Lilian E.; Berger, Christopher C.; Honhongva, Mikaela; Gazzaley, Adam; Bargh, John A.

    2009-01-01

    While research on cognitive control has addressed the effects that different forms of cognitive interference have on behavior and the activities of certain brain regions, until recently scientific approaches have been silent regarding the effects of interference on subjective experience. We demonstrate that, at the level of the individual trial, participants can reliably introspect the subjective aspects (e.g., perceptions of difficulty, competition, and control) of responding in interference paradigms. Similar subjective effects were obtained for both expressed and unexpressed (subvocalized) actions. Few participants discerned the source of these effects. These basic findings illuminate aspects of cognitive control and cognitive effort. In addition, these data have implications for the study of response interference in affect and self-control, and they begin to address theories regarding the function of consciousness. PMID:19933564

  3. Caspar Controls Resistance to Plasmodium falciparum in Diverse Anopheline Species

    PubMed Central

    Garver, Lindsey S.; Dong, Yuemei; Dimopoulos, George

    2009-01-01

    Immune responses mounted by the malaria vector Anopheles gambiae are largely regulated by the Toll and Imd (immune deficiency) pathways via the NF-kappaB transcription factors Rel1 and Rel2, which are controlled by the negative regulators Cactus and Caspar, respectively. Rel1- and Rel2-dependent transcription in A. gambiae has been shown to be particularly critical to the mosquito's ability to manage infection with the rodent malaria parasite Plasmodium berghei. Using RNA interference to deplete the negative regulators of these pathways, we found that Rel2 controls resistance of A. gambiae to the human malaria parasite Plasmodium falciparum, whereas Rel 1 activation reduced infection levels. The universal relevance of this defense system across Anopheles species was established by showing that caspar silencing also prevents the development of P. falciparum in the major malaria vectors of Asia and South America, A. stephensi and A. albimanus, respectively. Parallel studies suggest that while Imd pathway activation is most effective against P. falciparum, the Toll pathway is most efficient against P. berghei, highlighting a significant discrepancy between the human pathogen and its rodent model. High throughput gene expression analyses identified a plethora of genes regulated by the activation of the two Rel factors and revealed that the Toll pathway played a more diverse role in mosquito biology than the Imd pathway, which was more immunity-specific. Further analyses of key anti-Plasmodium factors suggest they may be responsible for the Imd pathway–mediated resistance phenotype. Additionally, we found that the fitness cost caused by Rel2 activation through caspar gene silencing was undetectable in sugar-fed, blood-fed, and P. falciparum-infected female A. gambiae, while activation of the Toll pathway's Rel1 had a major impact. This study describes for the first time a single gene that influences an immune mechanism that is able to abort development of P. falciparum in Anopheline species. Further, this study addresses aspects of the molecular, evolutionary, and physiological consequences of the observed phenotype. These findings have implications for malaria control since broad-spectrum immune activation in diverse anopheline species offers a viable and strategic approach to develop novel malaria control methods worldwide. PMID:19282971

  4. Notional Examples and Benchmark Aspects of a Resilient Control System

    SciTech Connect

    Craig Rieger

    2010-08-01

    Digital control system technology has pervaded most industries, leading to improvements in the efficiency and reliability of the associated operations. However, the ease of distributing and connecting related control systems for the purposes of increasing performance has resulted in interdependencies that can lead to unexpected conditions. Even with less complex designs, operators and engineers alike are often left with competing goals that are difficult to resolve. A fundamental reason for this dichotomy is that responsibilities lie with different disciplines, and operations are hosted on separate control systems. In addition, with the rising awareness of cyber security and diverse human interactions with control systems, an understanding of human actions from a malicious and benevolent standpoint is necessary. Resilience considers the multiple facets of requirements that drive the performance of control systems in a holistic fashion, whether they are security or stability, stability or efficiency, human interactions or complex interdependencies. As will be shown by example, current research philosophies lack the depth or the focus on the control system application to satisfy these requirements, such as graceful degradation of hierarchical control while under cyber attack. A resilient control system promises to purposefully consider these diverse requirements, developing an adaptive capacity to complex events that can lead to failure of traditional control system designs.

  5. Notional Examples and Benchmark Aspects Of a Resilient Control System

    SciTech Connect

    Craig. G. Rieger

    2010-08-01

    Digital control system technology has pervaded most industries, leading to improvements in the efficiency and reliability of the associated operations. However, the ease of distributing and connecting related control systems for the purposes of increasing performance has resulted in interdependencies that can lead to unexpected conditions. Even with less complex designs, operators and engineers alike are often left with competing goals that are difficult to resolve. A fundamental reason for this dichotomy is that responsibilities lie with different disciplines, and operations are hosted on separate control systems. In addition, with the rising awareness of cyber security and diverse human interactions with control systems, an understanding of human actions from a malicious and benevolent standpoint is necessary. Resilience considers the multiple facets of requirements that drive the performance of control systems in a holistic fashion, whether they are security or stability, stability or efficiency, human interactions or complex interdependencies. As will be shown by example, current research philosophies lack the depth or the focus on the control system application to satisfy these requirements, such as graceful degradation of hierarchical control while under cyber attack. A resilient control system promises to purposefully consider these diverse requirements, developing an adaptive capacity to complex events that can lead to failure of traditional control system designs.

  6. Ethical and legal aspects of global tobacco control.

    PubMed

    Novotny, T E; Carlin, D

    2005-08-01

    On 28 February 2005, the Framework Convention on Tobacco Control came into force as a result of at least 40 countries becoming State Parties through ratification of this first ever health treaty sponsored by the World Health Organization. This article discusses the bioethical, trade, and legal aspects of global tobacco control. Special emphasis is given to globalisation of tobacco use and the challenges it poses to sovereign nations. It also advocates a bioethical basis in the pursuit of global solutions to expanding tobacco use. PMID:16046698

  7. Entomological aspects of filariasis control in Sri Lanka

    PubMed Central

    Lambrecht, F. L.

    1974-01-01

    Historical events and suitable environmental conditions in the southwestern coastal areas of Sri Lanka have led to the establishment of a zone of endemic filariasis caused by Wuchereria bancrofti and transmitted by Culex pipiens fatigans. The previous Brugia malayi foci, scattered over widely dispersed areas of the island, were apparently completely eliminated as a result of control of the Mansonia vectors by the destruction of the larval host plants in their swamp habitats. Control measures by the Anti-Filariasis Campaign against W. bancrofti and C. p. fatigans have greatly reduced the human infection rates in the endemic coastal belt and have kept the rate in the dense population to less than 1% over the last several years. This paper assesses the entomological aspects of the control programme during the years 1970-72. PMID:4619057

  8. Review on design and control aspects of ankle rehabilitation robots.

    PubMed

    Jamwal, Prashant K; Hussain, Shahid; Xie, Sheng Q

    2015-03-01

    Ankle rehabilitation robots can play an important role in improving outcomes of the rehabilitation treatment by assisting therapists and patients in number of ways. Consequently, few robot designs have been proposed by researchers which fall under either of the two categories, namely, wearable robots or platform-based robots. This paper presents a review of both kinds of ankle robots along with a brief analysis of their design, actuation and control approaches. While reviewing these designs it was observed that most of them are undesirably inspired by industrial robot designs. Taking note of the design concerns of current ankle robots, few improvements in the ankle robot designs have also been suggested. Conventional position control or force control approaches, being used in the existing ankle robots, have been reviewed. Apparently, opportunities of improvement also exist in the actuation as well as control of ankle robots. Subsequently, a discussion on most recent research in the development of novel actuators and advanced controllers based on appropriate physical and cognitive human-robot interaction has also been included in this review. Implications for Rehabilitation Ankle joint functions are restricted/impaired as a consequence of stroke or injury during sports or otherwise. Robots can help in reinstating functions faster and can also work as tool for recording rehabilitation data useful for further analysis. Evolution of ankle robots with respect to their design and control aspects has been discussed in the present paper and a novel design with futuristic control approach has been proposed. PMID:24320195

  9. Science aspects of a remotely controlled Mars surface roving vehicle.

    NASA Technical Reports Server (NTRS)

    Choate, R.; Jaffe, L. D.

    1973-01-01

    Particular attention is given to aspects pertinent to teleoperation, remote control, onboard control, and man-machine relationships in carrying out scientific operations with such a vehicle. It is assumed that landed operations would comprise one Martian year and that the traverse would extend across an area approximately 500 km wide. The mission is assumed to be planned for the early 1980s. Its objective is to obtain data which will aid in answering a number of questions regarding the history of the solar system, the formation of Mars, and the evolution of life on Mars. A series of candidate rover payloads is proposed to meet the requirements. The smallest payload includes a TV camera, a general-purpose manipulator arm, a crusher and siever, an X-ray diffractometer-spectrometer, a gravimeter, a magnetometer, meteorological instruments, and a radio transponder.

  10. Control aspects in nonlinear Hills equation

    NASA Astrophysics Data System (ADS)

    Barbanti, L.; Damasceno, B. C.

    2011-05-01

    The Hill's equations-even in the linear original version are a describer of phenomenon having chaotic flavor, giving sometimes very unusual situations. The theory of the so called intervals of instability in the equation provides the precise description for most of these phenomena. Considerations on nonlinearities into the Hill's equation is a quite recent task. The linearized version for almost of these systems it reduces to the Hill's classical linear one. In this paper, some indicative facts are pointed out on the possibility of having the linear system stabilizable and/or exactly controllable. As consequence of such an approach we get results having strong classical aspects, like the one talking about location of parameters in intervals of stability. A result for nonlinear proper periodic controls, is considered too.

  11. Manual control aspects of Space Station docking maneuvers

    NASA Technical Reports Server (NTRS)

    Brody, Adam R.; Ellis, Stephen R.

    1990-01-01

    Due to an increase in spacecraft traffic forecasted for the Space Station era, researchers are investigating manual control and other aspects of docking operations with hopes of increasing safety, productivity, and likelihood of success while decreasing cost. Experiments have been performed which revealed the effect of approach velocity, in-flight anomalies, and control mode. Displays have been designed to enable flight planners to more easily overcome the difficulties presented by orbital mechanics. Improved understanding of human factors in the docking mission and other orbital maneuvers will play a significant role in design tradeoffs concerning thruster size, docking fixture style and mass, and on-board trajectory planning displays. Incorporating both empirical and analytic results into current and future planning of missions occurring not only in earth orbit, but also for missions in lunar and Mars orbit, will expand the performance envelopes of the astronauts who participate in these missions.

  12. Herbivores and nutrients control grassland plant diversity via light limitation

    USGS Publications Warehouse

    Borer, Elizabeth T.; Seabloom, Eric W.; Gruner, Daniel S.; Harpole, W. Stanley; Hillebrand, Helmut; Lind, Eric M.; Alder, Peter B.; Alberti, Juan; Anderson, T. Michael; Bakker, Jonathan D.; Biederman, Lori; Blumenthal, Dana; Brown, Cynthia S.; Brudvig, Lars A.; Buckley, Yvonne M.; Cadotte, Marc; Chu, Cheng-Jin; Cleland, Elsa E.; Crawley, Michael J.; Daleo, Pedro; Damschen, Ellen Ingman; Davies, Kendi F.; DeCrappeo, Nicole M.; Du, Guozhen; Firn, Jennifer; Hautier, Yann; Heckman, Robert W.; Hector, Andy; HilleRisLambers, Janneke; Iribarne, Oscar; Klein, Julia A.; Knops, Johannes M.H.; La Pierre, Kimberly J.; Leakey, Andrew D.B.; Li, Wei; MacDougall, Andrew S.; McCulley, Rebecca L.; Melbourne, Brett A.; Mitchell, Charles E.; Moore, Joslin L.; Mortensen, Brent; O'Halloran, Lydia R.; Orrock, John L.; Pascual, Jesús; Prober, Suzanne M.; Pyke, David A.; Risch, Anita C.; Schuetz, Martin; Smith, Melinda D.; Stevens, Carly J.; Sullivan, Lauren L.; Williams, Ryan J.; Wragg, Peter D.; Wright, Justin P.; Yang, Louie H.

    2014-01-01

    Human alterations to nutrient cycles and herbivore communities are affecting global biodiversity dramatically. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.

  13. Herbivores and nutrients control grassland plant diversity via light limitation.

    PubMed

    Borer, Elizabeth T; Seabloom, Eric W; Gruner, Daniel S; Harpole, W Stanley; Hillebrand, Helmut; Lind, Eric M; Adler, Peter B; Alberti, Juan; Anderson, T Michael; Bakker, Jonathan D; Biederman, Lori; Blumenthal, Dana; Brown, Cynthia S; Brudvig, Lars A; Buckley, Yvonne M; Cadotte, Marc; Chu, Chengjin; Cleland, Elsa E; Crawley, Michael J; Daleo, Pedro; Damschen, Ellen I; Davies, Kendi F; DeCrappeo, Nicole M; Du, Guozhen; Firn, Jennifer; Hautier, Yann; Heckman, Robert W; Hector, Andy; HilleRisLambers, Janneke; Iribarne, Oscar; Klein, Julia A; Knops, Johannes M H; La Pierre, Kimberly J; Leakey, Andrew D B; Li, Wei; MacDougall, Andrew S; McCulley, Rebecca L; Melbourne, Brett A; Mitchell, Charles E; Moore, Joslin L; Mortensen, Brent; O'Halloran, Lydia R; Orrock, John L; Pascual, Jess; Prober, Suzanne M; Pyke, David A; Risch, Anita C; Schuetz, Martin; Smith, Melinda D; Stevens, Carly J; Sullivan, Lauren L; Williams, Ryan J; Wragg, Peter D; Wright, Justin P; Yang, Louie H

    2014-04-24

    Human alterations to nutrient cycles and herbivore communities are affecting global biodiversity dramatically. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light. PMID:24670649

  14. Cross-CZO Contrasts: Aspect Controls and Critical Zone Architecture

    NASA Astrophysics Data System (ADS)

    Clarke, B. A.; Kirby, E.; Burbank, D. W.; West, N.

    2013-12-01

    We investigate aspect controls on Critical Zone (CZ) architecture, mobile regolith transport, and landscape morphology, based on a cross-CZO comparison of 1) Niwot Ridge, Boulder Creek CZO (BcCZO), a high alpine site with minimal soil/veg cover, characterized by steep S-facing and shallow N-facing hillslopes and 2) Shale Hills CZO (SSHCZO), a temperate, densely-forested, soil-mantled site with steep N-facing slopes and shallow S-facing slopes. We use high-resolution 2D seismic tomography of P- and S-wave velocities (Vp, Vs) to characterize CZ architecture and constrain depths of weathering fronts, as well as the thickness, character, and transport efficiency of mobile regolith layers. The 2D imagery allows assessment of changes in material properties both lateral and vertical (depth), thus mapping variability in CZ structures along the survey profile. The combination of Vp and Vs are used to better quantify material properties, (i.e., elastics moduli, density, fractures porosity), rock-mass strength, and weathering intensity - and when applied to the very shallow subsurface can help constrain the transport efficiency (strength or erodibility) of mobile regolith layers On Niwot Ridge, the depth of the weathering front and thickness of mobile regolith are substantially greater on shallower N-facing slopes, consistent with frost/freeze driven processes. However, the depth of the weathering front far exceeds modeled extents of frost-cracking depth (for past or present climates), suggesting additional processes also influence deep weathering. Mobile regolith is considerably thicker on shallow N-facing aspects and composed of large, disintegrated cobbles, however, velocity-based estimates of transport efficiency are higher on S-facing slopes composed of small talus blocks and thin soil/veg cover. Although, thin mobile regolith on S-facing slopes may be weak (slow V), the lower gradient of N-facing slopes and southward asymmetry of the ridge divide, suggests that transport efficiency is greatest on N-facing slopes. This may be explained by the dominance of frost/freeze process, which can readily lift or break, and provide a remarkably efficient process to transport the thick mobile regolith layer of large cobbles. At SSHCZO, depths of weathering fronts are invariant with slope aspect, suggesting that aspect control is not a predominant mechanism driving regolith production. Mobile regolith thickness, however, is more than 2-fold greater on N-facing slopes. Additionally, the mobile regolith on both slope aspects is primarily composed of well-developed soils. N-facing soils are thicker with greater cohesion, moisture, and inclusion of rock fragments. This is consistent with velocity-based estimates of lower transport efficiency on N-facing slopes relative to the thin, dry, fine grained soils on S-facing slopes. These results suggest fundamental differences in CZ architecture, weathering processes, and the influence of slope aspect between BcCZO and SSHCZO

  15. Characteristics associated with the diversion of controlled medications among adolescents

    PubMed Central

    McCabe, Sean Esteban; West, Brady T.; Teter, Christian J.; Ross-Durow, Paula; Young, Amy; Boyd, Carol J.

    2011-01-01

    Background The objective of this study was to estimate the lifetime prevalence of diversion (i.e., trading, selling, giving away or loaning) of four classes of controlled medications (pain, stimulant, anti-anxiety, and sleeping) among adolescents, and to identify demographic and behavioral characteristics of adolescents who divert their own controlled medications. Methods A web-based survey was self-administered by 2744 secondary school students from two southeastern Michigan school districts in 20092010. The sample consisted of 51% females, 65% Whites, 29% African-Americans, 4% Asians, 1% Hispanics and 1% from other racial categories. Results Thirty-three percent of the students had ever been prescribed at least one controlled pain, stimulant, anti-anxiety, or sleeping medication. Approximately 13.8% (n = 117) of lifetime prescribed users of controlled medications (n = 848) had ever traded, sold, given away or loaned their medications. Multiple logistic regression analyses indicated that being approached to divert medications, nonmedical use of prescription medications, externalizing behaviors, and being non-White were significantly associated with the diversion of controlled medications. Multiple logistic regression analysis indicated that the odds of substance use and abuse for lifetime prescribed users who diverted their controlled medications were significantly greater than prescribed users who never diverted. Conclusions The findings indicate that approximately one in seven prescribed users had diverted their controlled medications in their lifetimes. Being approached to divert medications and substance use are more prevalent among adolescents who diverted their controlled medications. Careful assessments, diligent prescribing and monitoring of controlled medications, and continual patient education could be useful in reducing medication diversion. PMID:21665384

  16. Optimal control of flood diversion in watershed using nonlinear optimization

    NASA Astrophysics Data System (ADS)

    Ding, Yan; Wang, Sam S. Y.

    2012-08-01

    This study aims to develop a simulation-based optimization model applicable to mitigate hazardous floods in storm events in a watershed which consists of a complex channel network and irregular topography. A well-established model, CCHE1D, is used as the simulation model to predict water stages and discharges of unsteady flood flows in a channel network, in which irregular (i.e. non-rectangular and non-prismatic) cross-sections are taken into account. Based on the variational principle, the adjoint equations are derived from the nonlinear hydrodynamic equations of CCHE1D, which are to establish a unique relationship between flood control variables and hydrodynamic variables. The internal conditions at the confluence in channel network for solving the adjoint equations in a watershed are obtained. An implicit numerical scheme (i.e. Preissman's scheme) is implemented for discretizing and solving the adjoint equations with the derived internal conditions and boundary conditions. The applicability of this integrated optimization model is demonstrated by searching for the optimal diversion hydrographs for withdrawing flood waters through a single floodgate and multiple floodgates into detention basins. Numerical optimization results show that this integrated model is efficient and robust. It is found that the single-floodgate control leads to an unfavorable speed-up in river flow which may create extra erosions in the channel bed; and multiple-floodgates diversion control diverts less flood waters, therefore can be a cost-effective control action. This simulation-based optimization model is capable of determining the optimal schedules of diversion discharge, optimal floodgate locations, minimum capacities of flood water detention basins in rivers and watersheds.

  17. Herbivores and nutrients control grassland plant diversity via light limitation.

    SciTech Connect

    Borer, Elizabeth T.; et al, et al

    2014-01-01

    Human alterations to nutrient cycles1,2 and herbivore communities3–7 are affecting global biodiversity dramatically2. Ecological theory predicts these changes should be strongly counteractive: nutrient addition drives plant species loss through intensified competition for light, whereas herbivores prevent competitive exclusion by increasing ground-level light, particularly in productive systems8,9. Here we use experimental data spanning a globally relevant range of conditions to test the hypothesis that herbaceous plant species losses caused by eutrophication may be offset by increased light availability due to herbivory. This experiment, replicated in 40 grasslands on 6 continents, demonstrates that nutrients and herbivores can serve as counteracting forces to control local plant diversity through light limitation, independent of site productivity, soil nitrogen, herbivore type and climate. Nutrient addition consistently reduced local diversity through light limitation, and herbivory rescued diversity at sites where it alleviated light limitation. Thus, species loss from anthropogenic eutrophication can be ameliorated in grasslands where herbivory increases ground-level light.

  18. Molecular aspects of transport in thin films of controlled architecture

    SciTech Connect

    Not Available

    1992-01-01

    Work was done in two principal areas: characterization of diffusion in swollen polymer films both with and without a barrier layer, and initial investigations of molecular aspects of swelling using enhanced Raman spectroscopy.

  19. Controls on development and diversity of Early Archean stromatolites

    PubMed Central

    Allwood, Abigail C.; Grotzinger, John P.; Knoll, Andrew H.; Burch, Ian W.; Anderson, Mark S.; Coleman, Max L.; Kanik, Isik

    2009-01-01

    The ?3,450-million-year-old Strelley Pool Formation in Western Australia contains a reef-like assembly of laminated sedimentary accretion structures (stromatolites) that have macroscale characteristics suggestive of biological influence. However, direct microscale evidence of biologynamely, organic microbial remains or biosedimentary fabricshas to date eluded discovery in the extensively-recrystallized rocks. Recently-identified outcrops with relatively good textural preservation record microscale evidence of primary sedimentary processes, including some that indicate probable microbial mat formation. Furthermore, we find relict fabrics and organic layers that covary with stromatolite morphology, linking morphologic diversity to changes in sedimentation, seafloor mineral precipitation, and inferred microbial mat development. Thus, the most direct and compelling signatures of life in the Strelley Pool Formation are those observed at the microscopic scale. By examining spatiotemporal changes in microscale characteristics it is possible not only to recognize the presence of probable microbial mats during stromatolite development, but also to infer aspects of the biological inputs to stromatolite morphogenesis. The persistence of an inferred biological signal through changing environmental circumstances and stromatolite types indicates that benthic microbial populations adapted to shifting environmental conditions in early oceans. PMID:19515817

  20. Genetic diversity and some aspects of antimicrobial activity of lactic acid bacteria isolated from goat milk.

    PubMed

    Cavicchioli, Valria Quintana; Dornellas, Wesley Dos Santos; Perin, Luana Martins; Pieri, Fbio Alessandro; Franco, Bernadette Dora Gombossy de Melo; Todorov, Svetoslav Dimitrov; Nero, Lus Augusto

    2015-03-01

    Lactic acid bacteria (LAB, n?=?57) were previously obtained from raw goat milk, identified as Lactococcus spp. (n?=?24) and Enterococcus spp. (n?=?33), and characterized as bacteriocinogenic. Fingerprinting by pulsed field gel electrophoresis (PFGE) demonstrated high genetic diversity, and 30 strains were selected and exhibited strong antimicrobial activity against 46 target strains (LAB, spoilage, and foodborne pathogens). Six strains (Lactococcus lactis: GLc03 and GLc05; and Enterococcus durans: GEn09, GEn12, GEn14, and GEn17) were selected to characterize their bacteriocinogenic features, using Listeria monocytogenes ATCC 7644 as the target. The six strains produced bacteriocins at higher titer when incubated in MRS at 37 C up to 12 h, when compared to growth at 25 and 30 C. The produced bacteriocins kept their antimicrobial activity after exposure to 100 C for 2 h and 121 C for 20 min; the antimicrobial activity was also observed after treatment at pH 2.0 to 10.0, except for GLc03. L. monocytogenes populations were reduced approximately two logs after treatment with cell-free supernatants from the selected strains. These data show that goat milk can contain a diverse microbiota able to inhibit L. monocytogenes, a common pathogen found in dairy products, and can be potentially employed in biopreservation of food produced under different processing conditions. PMID:25637509

  1. Bioremediation of petroleum pollutants: Diversity and environmental aspects of hydrocarbon biodegradation

    SciTech Connect

    Atlas, R.M.; Cerniglia, C.E.

    1995-05-01

    The manufacture, transportation, and distribution of petroleum and chemical products during the last century has resulted in hydrocarbon-contamination becoming a major environmental problem. Most of the environmental inputs of petroleum are accommodated largely due to the capacities of microorganisms to biodegrade hydrocarbons. Bioremediation has gained significant political support among competing technologies for in situ cleanup of pollutants. In addition to its potential for local cleanup of contaminated water and soil, bioremediation may have a future role in solving problems on a global scale, including removal of greenhouse gases from the atmosphere. This article examines in detail the following topics: bacterial and fungal metabolism of hydrocarbons; bioremediation of marine oil spills; site remediation; performance and regulatory oversight. In summary diverse microorganisms using diverse metabolic pathways have the capacities for degrading a wide spectrum of hydrocarbon structures in petroleum. Some pathways lead to detoxification and destruction of the pollutants whereas others activate potentially harmful compounds. In most cases of detoxification, environmental modification is used to stimulate the biodegradative activities of indigenous organisms. Biodegradation is emerging as an important cost-effective treatment for marine oil spills and contaminated sites. 13 refs., 2 figs.

  2. The Great Diversion: Danube Delta under Human Control (Invited)

    NASA Astrophysics Data System (ADS)

    Giosan, L.

    2009-12-01

    Many deltas around the world are suffering from sediment deficits that render them unstable to current and predicted rates of sea level rise. One solution proposed to alleviate the complete or partial drowning of such deltas is the use of river diversions to increase the quantity of sediment supplied to the delta plain to support marsh accretion. We examine the results of a half century old program of diversion in the Danube delta that led to the creation of an extensive diversion channel network akin in scope and size to a natural deltaic network. Danubes importance as a shipping route increased after the Crimean War in the 1850s; the European Danube Commission was charged with maintaining the Sulina distributary as a shipping channel until 1940s. In the same period, several canals were dug to aid fishing in lakes and bring freshwater to brackish lagoons. After World War II, Communist authorities dramatically increased the number of canals for fishing, fish-farming and reed harvesting. New data on sedimentation rates and estimates of sediment fluxes suggest that the intensive canalization in the second half of the 20th Century led to increased sediment deposition that compensated the decreasing sediment discharge linked to damming within the internal fluvial part of the delta; however, the external marine delta has become increasingly sediment starved during the same interval. We emphasize the similarities and contrasts between the human-controlled and natural deltaic channel networks of the Danube delta and discuss the sustainability of the delta as a sediment budget problem within a sea level rise context.

  3. Multiple replication origins with diverse control mechanisms in Haloarcula hispanica

    PubMed Central

    Wu, Zhenfang; Liu, Jingfang; Yang, Haibo; Liu, Hailong; Xiang, Hua

    2014-01-01

    The use of multiple replication origins in archaea is not well understood. In particular, little is known about their specific control mechanisms. Here, we investigated the active replication origins in the three replicons of a halophilic archaeon, Haloarcula hispanica, by extensive gene deletion, DNA mutation and genome-wide marker frequency analyses. We revealed that individual origins are specifically dependent on their co-located cdc6 genes, and a single active origin/cdc6 pairing is essential and sufficient for each replicon. Notably, we demonstrated that the activities of oriC1 and oriC2, the two origins on the main chromosome, are differently controlled. A G-rich inverted repeat located in the internal region between the two inverted origin recognition boxes (ORBs) plays as an enhancer for oriC1, whereas the replication initiation at oriC2 is negatively regulated by an ORB-rich region located downstream of oriC2-cdc6E, likely via Cdc6E-titrating. The oriC2 placed on a plasmid is incompatible with the wild-type (but not the ΔoriC2) host strain, further indicating that strict control of the oriC2 activity is important for the cell. This is the first report revealing diverse control mechanisms of origins in haloarchaea, which has provided novel insights into the use and coordination of multiple replication origins in the domain of Archaea. PMID:24271389

  4. Multiple replication origins with diverse control mechanisms in Haloarcula hispanica.

    PubMed

    Wu, Zhenfang; Liu, Jingfang; Yang, Haibo; Liu, Hailong; Xiang, Hua

    2014-02-01

    The use of multiple replication origins in archaea is not well understood. In particular, little is known about their specific control mechanisms. Here, we investigated the active replication origins in the three replicons of a halophilic archaeon, Haloarcula hispanica, by extensive gene deletion, DNA mutation and genome-wide marker frequency analyses. We revealed that individual origins are specifically dependent on their co-located cdc6 genes, and a single active origin/cdc6 pairing is essential and sufficient for each replicon. Notably, we demonstrated that the activities of oriC1 and oriC2, the two origins on the main chromosome, are differently controlled. A G-rich inverted repeat located in the internal region between the two inverted origin recognition boxes (ORBs) plays as an enhancer for oriC1, whereas the replication initiation at oriC2 is negatively regulated by an ORB-rich region located downstream of oriC2-cdc6E, likely via Cdc6E-titrating. The oriC2 placed on a plasmid is incompatible with the wild-type (but not the ?oriC2) host strain, further indicating that strict control of the oriC2 activity is important for the cell. This is the first report revealing diverse control mechanisms of origins in haloarchaea, which has provided novel insights into the use and coordination of multiple replication origins in the domain of Archaea. PMID:24271389

  5. Physical, consumer, and social aspects of measuring the food environment among diverse low-income populations.

    PubMed

    Gittelsohn, Joel; Sharma, Sangita

    2009-04-01

    Obesity and other diet-related chronic diseases are directly related to the food environment. We describe how to better assess the food environment in specific ethnic minority settings for designing and implementing interventions, based on a review of our previous work on the food environment in American Indian reservations, Canadian First Nations reserves, the Republic of the Marshall Islands, and inner-city Baltimore. The types of food stores available within each setting and the range of healthy foods available varied greatly across these geographic regions. In all settings, proximity to food stores/supermarkets, cost, and limited availability of healthful foods were common features, which limited access to health-promoting food options. Features specific to each population should be considered in an assessment of the food environment, including physical (e.g., openness of stores, mix of types of food sources); consumer (e.g., adequacy of the food supply, seasonal factors); and social (e.g., inter-household food sharing, perceptions of food quality, language differences) aspects. The food environments common in low-income ethnic subpopulations require special focus and consideration due to the vulnerability of the populations and to specific and unique aspects of each setting. PMID:19285208

  6. Aspects of Benthic Decapod Diversity and Distribution from Rocky Nearshore Habitat at Geographically Widely Dispersed Sites

    PubMed Central

    Pohle, Gerhard; Iken, Katrin; Clarke, K. Robert; Trott, Thomas; Konar, Brenda; Cruz-Motta, Juan José; Wong, Melisa; Benedetti-Cecchi, Lisandro; Mead, Angela; Miloslavich, Patricia; Mieszkowska, Nova; Milne, Rebecca; Tamburello, Laura; Knowlton, Ann; Kimani, Edward; Shirayama, Yoshihisa

    2011-01-01

    Relationships of diversity, distribution and abundance of benthic decapods in intertidal and shallow subtidal waters to 10 m depth are explored based on data obtained using a standardized protocol of globally-distributed samples. Results indicate that decapod species richness overall is low within the nearshore, typically ranging from one to six taxa per site (mean = 4.5). Regionally the Gulf of Alaska decapod crustacean community structure was distinguishable by depth, multivariate analysis indicating increasing change with depth, where assemblages of the high and mid tide, low tide and 1 m, and 5 and 10 m strata formed three distinct groups. Univariate analysis showed species richness increasing from the high intertidal zone to 1 m subtidally, with distinct depth preferences among the 23 species. A similar depth trend but with peak richness at 5 m was observed when all global data were combined. Analysis of latitudinal trends, confined by data limitations, was equivocal on a global scale. While significant latitudinal differences existed in community structure among ecoregions, a semi-linear trend in changing community structure from the Arctic to lower latitudes did not hold when including tropical results. Among boreal regions the Canadian Atlantic was relatively species poor compared to the Gulf of Alaska, whereas the Caribbean and Sea of Japan appeared to be species hot spots. While species poor, samples from the Canadian Atlantic were the most diverse at the higher infraordinal level. Linking 11 environmental variables available for all sites to the best fit family-based biotic pattern showed a significant relationship, with the single best explanatory variable being the level of organic pollution and the best combination overall being organic pollution and primary productivity. While data limitations restrict conclusions in a global context, results are seen as a first-cut contribution useful in generating discussion and more in-depth work in the still poorly understood field of biodiversity distribution. PMID:21533220

  7. Biologically controlled water diversion demonstrated by new visual experimental technique

    SciTech Connect

    Paulsen, J.E.; Oppen, E.; Vatland, A.; Hanssen, J.E.

    1994-12-31

    A microbial enhanced oil recovery (MEOR) technology for optimization of waterflood sweep efficiency was studied using a transparent pore micro model and a recently developed cybernetic image processing method (Automated Microscope Observation Reaction System = AMORS). Indigenous seawater microbes were stimulated with a nutrient package and allowed to develop inside the once through flow cell; a replica of the pore structure of a North Sea sandstone reservoir. The use of micro models fitted with the AMORS package is an important step in revealing the nature of microbial blocking phenomena in porous matrices. Reservoir potential evaluation and consideration of MEOR process logistics, as compared to alternative treatment methods indicates that selective biological diversion may be a highly cost-effective and controllable way of optimizing waterflood sweep efficiency in many North Sea reservoirs. AMORS is a flexible tool recommended for investigating processes that take place on a micro/macro scale.

  8. Adaptive Fuzzy Control of a Direct Drive Motor: Experimental Aspects

    NASA Technical Reports Server (NTRS)

    Medina, E.; Akbarzadeh-T, M.-R.; Kim, Y. T.

    1998-01-01

    This paper presents a state feedback adaptive control method for position and velocity control of a direct drive motor. The proposed control scheme allows for integrating heuristic knowledge with mathematical knowledge of a system. It performs well even when mathematical model of the system is poorly understood. The controller consists of an adaptive fuzzy controller and a supervisory controller. The supervisory controller requires only knowledge of the upper bound and lower bound of the system parameters. The fuzzy controller is based on fuzzy basis functions and states of the system. The adaptation law is derived based on the Lyapunov function which ensures that the state of the system asymptotically approaches zero. The proposed controller is applied to a direct drive motor with payload and parameter uncertainty, and the effectiveness is experimentally verified. The real-time performance is compared with simulation results.

  9. Semiotic aspects of control and modeling relations in complex systems

    SciTech Connect

    Joslyn, C.

    1996-08-01

    A conceptual analysis of the semiotic nature of control is provided with the goal of elucidating its nature in complex systems. Control is identified as a canonical form of semiotic relation of a system to its environment. As a form of constraint between a system and its environment, its necessary and sufficient conditions are established, and the stabilities resulting from control are distinguished from other forms of stability. These result from the presence of semantic coding relations, and thus the class of control systems is hypothesized to be equivalent to that of semiotic systems. Control systems are contrasted with models, which, while they have the same measurement functions as control systems, do not necessarily require semantic relations because of the lack of the requirement of an interpreter. A hybrid construction of models in control systems is detailed. Towards the goal of considering the nature of control in complex systems, the possible relations among collections of control systems are considered. Powers arguments on conflict among control systems and the possible nature of control in social systems are reviewed, and reconsidered based on our observations about hierarchical control. Finally, we discuss the necessary semantic functions which must be present in complex systems for control in this sense to be present at all.

  10. Analysis of Anoxybacillus Genomes from the Aspects of Lifestyle Adaptations, Prophage Diversity, and Carbohydrate Metabolism

    PubMed Central

    Goh, Kian Mau; Gan, Han Ming; Chan, Kok-Gan; Chan, Giek Far; Shahar, Saleha; Chong, Chun Shiong; Kahar, Ummirul Mukminin; Chai, Kian Piaw

    2014-01-01

    Species of Anoxybacillus are widespread in geothermal springs, manure, and milk-processing plants. The genus is composed of 22 species and two subspecies, but the relationship between its lifestyle and genome is little understood. In this study, two high-quality draft genomes were generated from Anoxybacillus spp. SK3-4 and DT3-1, isolated from Malaysian hot springs. De novo assembly and annotation were performed, followed by comparative genome analysis with the complete genome of Anoxybacillus flavithermus WK1 and two additional draft genomes, of A. flavithermus TNO-09.006 and A. kamchatkensis G10. The genomes of Anoxybacillus spp. are among the smaller of the family Bacillaceae. Despite having smaller genomes, their essential genes related to lifestyle adaptations at elevated temperature, extreme pH, and protection against ultraviolet are complete. Due to the presence of various competence proteins, Anoxybacillus spp. SK3-4 and DT3-1 are able to take up foreign DNA fragments, and some of these transferred genes are important for the survival of the cells. The analysis of intact putative prophage genomes shows that they are highly diversified. Based on the genome analysis using SEED, many of the annotated sequences are involved in carbohydrate metabolism. The presence of glycosyl hydrolases among the Anoxybacillus spp. was compared, and the potential applications of these unexplored enzymes are suggested here. This is the first study that compares Anoxybacillus genomes from the aspect of lifestyle adaptations, the capacity for horizontal gene transfer, and carbohydrate metabolism. PMID:24603481

  11. Temporal Patterns of Ant Diversity across a Mountain with Climatically Contrasting Aspects in the Tropics of Africa

    PubMed Central

    Munyai, Thinandavha Caswell; Foord, Stefan Hendrik

    2015-01-01

    Factors that drive species richness over space and time are still poorly understood and are often context specific. Identifying these drivers for ant diversity has become particularly relevant within the context of contemporary global change events. We report on a long-term bi-annual (wet and dry seasons), standardized sampling of epigeal ants over a five year period on the mesic and arid aspects of an inselberg (Soutpansberg Mountain Range) in the tropics of Africa. We detail seasonal, annual and long-term trends of species density, test the relative contribution of geometric constraints, energy, available area, climate, local environmental variables, time, and space in explaining ant species density patterns through Generalized Linear Mixed Models (GLMM) where replicates were included as random factors to account for temporal pseudo-replication. Seasonal patterns were very variable and we found evidence of decreased seasonal variation in species density with increased elevation. The extent and significance of a decrease in species density with increased elevation varied with season. Annual patterns point to an increase in ant diversity over time. Ant density patterns were positively correlated with mean monthly temperature but geometric constraints dominated model performance while soil characteristics were minor correlates. These drivers and correlates accounted for all the spatio-temporal variability in the database. Ant diversity was therefore mainly determined by geometric constraints and temperature while soil characteristics (clay and carbon content) accounted for smaller but significant amounts of variation. This study documents the role of season, elevation and their interaction in affecting ant species densities while highlighting the importance of neutral processes and temperature in driving these patterns. PMID:25774670

  12. Temporal patterns of ant diversity across a mountain with climatically contrasting aspects in the tropics of Africa.

    PubMed

    Munyai, Thinandavha Caswell; Foord, Stefan Hendrik

    2015-01-01

    Factors that drive species richness over space and time are still poorly understood and are often context specific. Identifying these drivers for ant diversity has become particularly relevant within the context of contemporary global change events. We report on a long-term bi-annual (wet and dry seasons), standardized sampling of epigeal ants over a five year period on the mesic and arid aspects of an inselberg (Soutpansberg Mountain Range) in the tropics of Africa. We detail seasonal, annual and long-term trends of species density, test the relative contribution of geometric constraints, energy, available area, climate, local environmental variables, time, and space in explaining ant species density patterns through Generalized Linear Mixed Models (GLMM) where replicates were included as random factors to account for temporal pseudo-replication. Seasonal patterns were very variable and we found evidence of decreased seasonal variation in species density with increased elevation. The extent and significance of a decrease in species density with increased elevation varied with season. Annual patterns point to an increase in ant diversity over time. Ant density patterns were positively correlated with mean monthly temperature but geometric constraints dominated model performance while soil characteristics were minor correlates. These drivers and correlates accounted for all the spatio-temporal variability in the database. Ant diversity was therefore mainly determined by geometric constraints and temperature while soil characteristics (clay and carbon content) accounted for smaller but significant amounts of variation. This study documents the role of season, elevation and their interaction in affecting ant species densities while highlighting the importance of neutral processes and temperature in driving these patterns. PMID:25774670

  13. On Social and Material Aspects of Technological Control.

    ERIC Educational Resources Information Center

    Herfel, William E.

    1999-01-01

    Suggests that Hugh Lacey's example of a clear-cut distinction between material and social constraints or possibilities in the Green Revolution is misleading. Proposes a material analysis of the control situation placed within the material framework of the social structure within which the control system is employed. (Author/WRM)

  14. Diversity Strategies for Nuclear Power Plant Instrumentation and Control Systems

    SciTech Connect

    Wood, Richard Thomas; Belles, Randy; Cetiner, Mustafa Sacit; Holcomb, David Eugene; Korsah, Kofi; Loebl, Andy; Mays, Gary T; Muhlheim, Michael David; Mullens, James Allen; Poore III, Willis P; Qualls, A L; Wilson, Thomas L; Waterman, Michael E.

    2010-02-01

    This report presents the technical basis for establishing acceptable mitigating strategies that resolve diversity and defense-in-depth (D3) assessment findings and conform to U.S. Nuclear Regulatory Commission (NRC) requirements. The research approach employed to establish appropriate diversity strategies involves investigation of available documentation on D3 methods and experience from nuclear power and nonnuclear industries, capture of expert knowledge and lessons learned, determination of best practices, and assessment of the nature of common-cause failures (CCFs) and compensating diversity attributes. The research described in this report does not provide guidance on how to determine the need for diversity in a safety system to mitigate the consequences of potential CCFs. Rather, the scope of this report provides guidance to the staff and nuclear industry after a licensee or applicant has performed a D3 assessment per NUREG/CR-6303 and determined that diversity in a safety system is needed for mitigating the consequences of potential CCFs identified in the evaluation of the safety system design features. Succinctly, the purpose of the research described in this report was to answer the question, 'If diversity is required in a safety system to mitigate the consequences of potential CCFs, how much diversity is enough?' The principal results of this research effort have identified and developed diversity strategies, which consist of combinations of diversity attributes and their associated criteria. Technology, which corresponds to design diversity, is chosen as the principal system characteristic by which diversity criteria are grouped to form strategies. The rationale for this classification framework involves consideration of the profound impact that technology-focused design diversity provides. Consequently, the diversity usage classification scheme involves three families of strategies: (1) different technologies, (2) different approaches within the same technology, and (3) different architectures within the same technology. Using this convention, the first diversity usage family, designated Strategy A, is characterized by fundamentally diverse technologies. Strategy A at the system or platform level is illustrated by the example of analog and digital implementations. The second diversity usage family, designated Strategy B, is achieved through the use of distinctly different technologies. Strategy B can be described in terms of different digital technologies, such as the distinct approaches represented by general-purpose microprocessors and field-programmable gate arrays. The third diversity usage family, designated Strategy C, involves the use of variations within a technology. An example of Strategy C involves different digital architectures within the same technology, such as that provided by different microprocessors (e.g., Pentium and Power PC). The grouping of diversity criteria combinations according to Strategies A, B, and C establishes baseline diversity usage and facilitates a systematic organization of strategic approaches for coping with CCF vulnerabilities. Effectively, these baseline sets of diversity criteria constitute appropriate CCF mitigating strategies for digital safety systems. The strategies represent guidance on acceptable diversity usage and can be applied directly to ensure that CCF vulnerabilities identified through a D3 assessment have been adequately resolved. Additionally, a framework has been generated for capturing practices regarding diversity usage and a tool has been developed for the systematic assessment of the comparative effect of proposed diversity strategies (see Appendix A).

  15. Control aspects of motor neural prosthesis: sensory interface.

    PubMed

    Popović, Dejan B; Dosen, Strahinja; Popović, Mirjana B; Stefanović, Filip; Kojović, Jovana

    2007-01-01

    A neural prosthesis (NP) has two applications: permanent assistance of function, and temporary assistance that contributes to long-term recovery of function. Here, we address control issues for a therapeutic NP which uses surface electrodes. We suggest that the effective NP for therapy needs to implement rule-based control. Rule-based control relies on the triggering of preprogrammed sequences of electrical stimulation by the sensory signals. The sensory system in the therapeutic NP needs to be simple for installation, allow self-calibration, it must be robust, and sufficiently redundant in order to guarantee safe operation. The sensory signals need to generate control signals; hence, sensory fusion is needed. MEMS technology today provides sensors that fulfill the technical requirements (accelerometers, gyroscopes, force sensing resistors). Therefore, the task was to design a sensory signal processing method from the mentioned solid state sensors that would recognize phases during the gait cycle. This is necessary for the control of multi channel electrical stimulation. The sensory fusion consists of the following two phases: 1) estimation of vertical and horizontal components of the ground reaction force, center of pressure, and joint angles from the solid-state sensors, and 2) fusion of the estimated signals into a sequence of command signals. The first phase was realized by the use of artificial neural networks and adaptive neuro-fuzzy inference systems, while the second by the use of inductive learning described in our earlier work [1]. PMID:18002969

  16. On the control aspect of laser frequency stabilization

    NASA Technical Reports Server (NTRS)

    Zia, Omar

    1991-01-01

    Realization of frequency stable lasers is viewed as key to progress in many areas of research; therefore, the search for more effective techniques of frequency stabilization has intensified significantly in recent years. Investigating and validating the fundamental linewidth and frequency stability limits of a Nd:YAG laser oscillator, locked to a high finesse reference cavity in the microgravity and vibration-free environment of space, is the objective of a NASA project called SUNLITE at LaRC. The objective of this paper is to further investigate the application of feedback control theory in active frequency control as a frequency stabilization technique and determine the most appropriate control strategy to be used in general and particularly in the SUNLITE Project.

  17. Acoustic Aspects of Active-Twist Rotor Control

    NASA Technical Reports Server (NTRS)

    Booth, Earl R., Jr.; Wilbur, Matthew L.

    2002-01-01

    The use of an Active Twist Rotor system to provide both vibration reduction and performance enhancement has been explored in recent analytical and experimental studies. Effects of active-twist control on rotor noise, however, had not been determined. During a recent wind tunnel test of an active-twist rotor system, a set of acoustic measurements were obtained to assess the effects of active-twist control on noise produced by the rotor, especially blade-vortex interaction (BVI) noise. It was found that for rotor operating conditions where BVI noise is dominant, active-twist control provided a reduction in BVI noise level. This BVI noise reduction was almost, but not quite, as large as that obtained in a similar test using HHC. However, vibration levels were usually adversely affected at operating conditions favoring minimum BVI noise. Conversely, operating conditions favoring minimum vibration levels affected BVI noise levels, but not always adversely.

  18. Some aspects of robotics calibration, design and control

    NASA Technical Reports Server (NTRS)

    Tawfik, Hazem

    1990-01-01

    The main objective is to introduce techniques in the areas of testing and calibration, design, and control of robotic systems. A statistical technique is described that analyzes a robot's performance and provides quantitative three-dimensional evaluation of its repeatability, accuracy, and linearity. Based on this analysis, a corrective action should be taken to compensate for any existing errors and enhance the robot's overall accuracy and performance. A comparison between robotics simulation software packages that were commercially available (SILMA, IGRIP) and that of Kennedy Space Center (ROBSIM) is also included. These computer codes simulate the kinematics and dynamics patterns of various robot arm geometries to help the design engineer in sizing and building the robot manipulator and control system. A brief discussion on an adaptive control algorithm is provided.

  19. Aspects of Numerical Simulation of Circulation Control Airfoils

    NASA Technical Reports Server (NTRS)

    Swanson, R. C.; Rumsey, C. L.; Anders, S. G.

    2005-01-01

    The mass-averaged compressible Navier-Stokes equations are solved for circulation control airfoils. Numerical solutions are computed with a multigrid method that uses an implicit approximate factorization smoother. The effects of flow conditions (e.g., free-stream Mach number, angle of attack, momentum coefficient) and mesh on the prediction of circulation control airfoil flows are considered. In addition, the impact of turbulence modeling, including curvature effects and modifications to reduce eddy viscosity levels in the wall jet (i.e., Coanda flow), is discussed. Computed pressure distributions are compared with available experimental data.

  20. Self-Esteem, Locus of Control and Various Aspects of Psychopathology of Adults with Visual Impairments

    ERIC Educational Resources Information Center

    Papadopoulos, Konstantinos; Paralikas, Theodosis; Barouti, Marialena; Chronopoulou, Elena

    2014-01-01

    The exploratory study presented in this article looks into the possible differences in psychosocial aspects (self-esteem and locus of control) and aspects of psychopathology (depression, anxiety, melancholia, asthenia, and mania) amongst sighted adults and adults with visual impairments. Moreover, the study aims to examine the possible

  1. Prediction, control, and decision-making aspects for chaotic systems

    SciTech Connect

    Protopopescu, V.

    1990-01-01

    Several examples of chaotic systems are discussed for which occurrence of chaos, information recovery, control, and decision- making processes appear in a new, sometimes counterintuitive light. From case to case, explanations, conjectures, and/or possible applications are indicated. 14 refs.

  2. Molecular Aspects of Transport in Thin Films of Controlled Architecture

    SciTech Connect

    Paul W. Bohn

    2009-04-16

    Our laboratory focuses on developing spatially localized chemistries which can produce structures of controlled architecture on the supermolecular length scale -- structures which allow us to control the motion of molecular species with high spatial resolution, ultimately on nanometer length scales. Specifically, nanocapillary array membranes (NCAMs) contain an array of nanometer diameter pores connecting vertically separated microfluidic channels. NCAMs can manipulate samples with sub-femtoliter characteristic volumes and attomole sample amounts and are opening the field of chemical analysis of mass-limited samples, because they are capable of digital control of fluid switching down to sub-attoliter volumes; extension of analytical “unit operations” down to sub-femtomole sample sizes; and exerting spatiotemporal control over fluid mixing to enable studies of reaction dynamics. Digital flow switching mediated by nanocapillary array membranes can be controlled by bias, ionic strength, or pore diameter and is being studied by observing the temporal characteristics of transport across a single nanopore in thin PMMA membranes. The control of flow via nanopore surface characteristics, charge density and functional group presentation, is being studied by coupled conductivity and laser-induced fluorescence (LIF) measurements. Reactive mixing experiments previously established low millisecond mixing times for NCAM-mediated fluid transfer, and this has been exploited to demonstrate capture of mass-limited target species by Au colloids. Voltage and thermally-activated polymer switches have been developed for active control of transport in NCAMs. Thermally-switchable and size-selective transport was achieved by grafting poly(N-isopropylacrylamide) brushes onto the exterior surface of a Au-coated polycarbonate track-etched membrane, while the voltage-gated properties of poly(hydroxyethylmethacrylate) were characterized dynamically. Electrophoretic separations have been coupled to analyte sampling both by LIF and mass spectrometry. Detection of electrophoresis separation products by electrospray mass spectrometry was achieved through direct interfacing to an electrospray mass spectrometer. Pb(II) interactions with the DNAzyme have been realized in an NCAM-coupled integrated microfluidic structure allowing cation separations to be coupled to molecular beacon detection motifs for the determination of Pb(II) in an electroplating sludge reference material. By changing the DNAzyme to select for other compounds of interest, it is possible to incorporate multiple sensing systems within a single device, thereby achieving great flexibility.

  3. Control aspects of quantum computing using pure and mixed states

    PubMed Central

    Schulte-Herbrggen, Thomas; Marx, Raimund; Fahmy, Amr; Kauffman, Louis; Lomonaco, Samuel; Khaneja, Navin; Glaser, Steffen J.

    2012-01-01

    Steering quantum dynamics such that the target states solve classically hard problems is paramount to quantum simulation and computation. And beyond, quantum control is also essential to pave the way to quantum technologies. Here, important control techniques are reviewed and presented in a unified frame covering quantum computational gate synthesis and spectroscopic state transfer alike. We emphasize that it does not matter whether the quantum states of interest are pure or not. While pure states underly the design of quantum circuits, ensemble mixtures of quantum states can be exploited in a more recent class of algorithms: it is illustrated by characterizing the Jones polynomial in order to distinguish between different (classes of) knots. Further applications include Josephson elements, cavity grids, ion traps and nitrogen vacancy centres in scenarios of closed as well as open quantum systems. PMID:22946034

  4. Economic aspects of Q fever control in dairy goats.

    PubMed

    van Asseldonk, M A P M; Bontje, D M; Backer, J A; Roermund, H J W van; Bergevoet, R H M

    2015-09-01

    This paper presents an economic analysis of Q fever control strategies in dairy goat herds in The Netherlands. Evaluated control strategies involved vaccination strategies (being either preventive or reactive) and reactive non-vaccination strategies (i.e., culling or breeding prohibition). Reactive strategies were initiated after PCR positive bulk tank milk or after an abortion storm (abortion percentage in the herd of 5% or more). Preventive vaccination eradicates Q fever in a herd on average within 2 and 7 years (depending on breeding style and vaccination strategy). Economic outcomes reveal that preventive vaccination is always the preferred Q fever control strategy on infected farms and this even holds for a partial analysis if only on-farm costs and benefits are accounted for and human health costs are ignored. Averted human health costs depend to a large extend on the number of infected human cases per infected farm or animal. Much is yet unknown with respect to goat-human transmission rates. When the pathogen is absent in both livestock and farm environment then the "freedom of Q fever disease" is achieved. This would enable a return to non-vaccinated herds but more insight is required with respect to the mechanisms and probability of re-infection. PMID:26164531

  5. Aspects of droplet and particle size control in miniemulsions

    NASA Astrophysics Data System (ADS)

    Saygi-Arslan, Oznur

    Miniemulsion polymerization has become increasingly popular among researchers since it can provide significant advantages over conventional emulsion polymerization in certain cases, such as production of high-solids, low-viscosity latexes with better stability and polymerization of highly water-insoluble monomers. Miniemulsions are relatively stable oil (e.g., monomer) droplets, which can range in size from 50 to 500 nm, and are normally dispersed in an aqueous phase with the aid of a surfactant and a costabilizer. These droplets are the primary locus of the initiation of the polymerization reaction. Since particle formation takes place in the monomer droplets, theoretically, in miniemulsion systems the final particle size can be controlled by the initial droplet size. The miniemulsion preparation process typically generates broad droplet size distributions and there is no complete treatment in the literature regarding the control of the mean droplet size or size distribution. This research aims to control the miniemulsion droplet size and its distribution. In situ emulsification, where the surfactant is synthesized spontaneously at the oil/water interface, has been put forth as a simpler method for the preparation of miniemulsions-like systems. Using the in situ method of preparation, emulsion stability and droplet and particle sizes were monitored and compared with conventional emulsions and miniemulsions. Styrene emulsions prepared by the in situ method do not demonstrate the stability of a comparable miniemulsion. Upon polymerization, the final particle size generated from the in situ emulsion did not differ significantly from the comparable conventional emulsion polymerization; the reaction mechanism for in situ emulsions is more like conventional emulsion polymerization rather than miniemulsion polymerization. Similar results were found when the in situ method was applied to controlled free radical polymerizations (CFRP), which have been advanced as a potential application of the method. Molecular weight control was found to be achieved via diffusion of the CFRP agents through the aqueous phase owing to limited water solubilities. The effects of adsorption rate and energy on the droplet size and size distribution of miniemulsions using different surfactants (sodium lauryl sulfate (SLS), sodium dodecylbenzene sulfonate (SDBS), Dowfax 2A1, Aerosol OT-75PG, sodium n-octyl sulfate (SOS), and sodium n-hexadecyl sulfate (SHS)) were analyzed. For this purpose, first, the dynamics of surfactant adsorption at an oil/water interface were examined over a range of surfactant concentrations by the drop volume method and then adsorption rates of the different surfactants were determined for the early stages of adsorption. The results do not show a direct relationship between adsorption rate and miniemulsion droplet size and size distribution. Adsorption energies of these surfactants were also calculated by the Langmuir adsorption isotherm equation and no correlation between adsorption energy and miniemulsion droplet size was found. In order to understand the mechanism of miniemulsification process, the effects of breakage and coalescence processes on droplet size distributions were observed at different surfactant concentrations, monomer ratios, and homogenization conditions. A coalescence and breakup mechanism for miniemulsification is proposed to explain the size distribution of droplets. The multimodal droplet size distribution of ODMA miniemulsions was controlled by the breakage mechanism. The results also showed that, at a surfactant concentration when 100% surface coverage was obtained, the droplet size distribution became unimodal.

  6. [Economic aspects of the management and control of MRSA].

    PubMed

    Hbner, N-O; Hbner, C; Kramer, A

    2009-11-01

    Methicillin resistance of Staphylococcus aureus strains (MRSA) has become a steadily growing cost factor for the German and international health system. Besides direct costs for diagnostics and therapy, indirect and intangible costs are a considerable part in the total expenses. Because of the massive increase of MRSA in medical centres as well as in the population and further worsening of forced rationalizing in the health care systems, the interest in the economic effects of this phenomenon has increased greatly during the last years. For managing MRSA and for effective cost containment, especially in hospitals, infection control measures have not only to prevent the further spread of MRSA but actively reduce the number of colonised patients. In the last years the efficiency of several infection control measures and their combination to prevent the spread of MRSA has been shown. However, these measures are linked to considerable direct costs in the first place. Nevertheless, an overall economic assessment of hygiene measures is only possible after a complete cost-benefit analysis, where costs are compared to effects achieved. Moreover, analyses that focus on effects for single institutions only are as inappropriate as purely monetary analyses or analyses that include the direct additional only. Despite of at first considerable expenditures, not only infection control measures but proactive strategies to reduce the total number of MRSA cases (accordingly of the "Search and Destroy" philosophy) are shown to be cost efficient, even in low prevalence situations, based on examples in literature. Hence, effective programmes to reduce MRSA are not only necessary from a medical and ethical focus but are also cost efficient in medium term for health care providers and the community. PMID:19937566

  7. Algorithmic aspects of topology control problems for ad hoc networks

    SciTech Connect

    Liu, R.; Lloyd, E. L.; Marathe, M. V.; Ramanathan, R.; Ravi, S. S.

    2002-01-01

    Topology control problems are concerned with the assignment of power values to nodes of an ad hoc network so that the power assignment leads to a graph topology satisfying some specified properties. This paper considers such problems under several optimization objectives, including minimizing the maximum power and minimizing the total power. A general approach leading to a polynomial algorithm is presented for minimizing maximum power for a class of graph properties, called monotone properties. The difficulty of generalizing the approach to properties that are not monoione is pointed out. Problems involving the minimization of total power are known to be NP-complete even for simple graph properties. A general approach that leads to an approximation algorithm for minimizing the total power for some monotone properties is presented. Using this approach, a new approximation algorithm for the problem of minimizing the total power for obtaining a 2-node-connected graph is obtained. It is shown that this algorithm provides a constant performance guarantee. Experimental results from an implementation of the approximation algorithm are also presented.

  8. APPETITE CONTROL: METHODOLOGICAL ASPECTS OF THE EVALUATION OF FOODS

    PubMed Central

    Blundell, John; de Graaf, Cees; Hulshof, Toine; Jebb, Susan; Livingstone, Barbara; Lluch, Anne; Mela, David; Salah, Samir; Schuring, Ewoud; van der Knaap, Henk; Westerterp, Margriet

    2013-01-01

    This report describes a set of scientific procedures used to assess the impact of foods and food ingredients on the expression of appetite (psychological and behavioural). An overarching priority has been to enable potential evaluators of health claims about foods to identify justified claims, and to exclude claims that are not supported by scientific evidence for the effect cited. This priority follows precisely from the principles set down in the PASSCLAIM report. (4) The report allows the evaluation of the strength of health claims, about the effects of foods on appetite, which can be sustained on the basis of the commonly used scientific designs and experimental procedures. The report includes different designs for assessing effects on satiation as opposed to satiety,detailed coverage of the extent to which a change in hunger can stand-alone as a measure of appetite control, and an extensive discussion of the statistical procedures appropriate for handling data in this field of research. Since research in this area is continually evolving, new improved methodologies may emerge over time and will need to be incorporated into the framework. One main objective of the report has been to produce guidance on good practice in carrying out appetite research, and not to set down a series of commandments that must be followed. PMID:20122136

  9. Ethical aspects of the Revised National Tuberculosis Control Programme.

    PubMed

    Nair, S S

    2011-01-01

    This paper identifies some ethical concerns regarding the Revised National Tuberculosis Control Programme (RNTCP). Only 10% of those with chest symptoms visiting public health facilities get specific treatment as they are diagnosed with TB. The remaining 90% who suffer from non-TB diseases are not given scientific treatment. This compartmental approach denies treatment to millions of people with chest symptoms. It has also eroded the popularity of public health facilities. Second, though 87% of those diagnosed on the basis of x-ray alone are unlikely to have TB, such unethical wrong diagnoses continue to be carried out under the TB programme. Still worse, the RNTCP's expectation that only half of TB cases should be smear positive effectively permits up to 50% of diagnoses to be wrong. The actual extent of wrong diagnosis is even higher as the majority of people with chest symptoms first visit private health facilities which base their diagnosis almost exclusively on radiological examination. Third, though 25% to 33% of TB cases get cured spontaneously, and at least two-thirds were cured even with incomplete treatment, the RNTCP insists on full treatment for all TB cases. This over-treatment is unethical, wasteful and also tantamount to scientific dishonesty. Studies to identify different categories of cases (those needing full treatment, short treatment or no treatment) have not been attempted. The introduction (under the RNTCP) of the "success rate"in preference to the well recognised "cure rate" was unethical and unwarranted. "Crying wolf" over Multiple Drug Resistant (MDR) TB to justify DOTS when there is no apparent alarming increase in the incidence of initial MDR tuberculosis cases is also questionable. Other ethical concerns about the RNTCP include the irrational choice of districts leading to exclusion of those that need the services most; exclusion of diagnosed patients from the DOTS scheme, and exclusion from treatment on non-medical grounds. Such exclusions can be up to 58% of TB cases. PMID:22106620

  10. Preventing Large-Scale Controlled Substance Diversion From Within the Pharmacy

    PubMed Central

    Martin, Emory S.; Dzierba, Steven H.; Jones, David M.

    2013-01-01

    Large-scale diversion of controlled substances (CS) from within a hospital or heath system pharmacy is a rare but growing problem. It is the responsibility of pharmacy leadership to scrutinize control processes to expose weaknesses. This article reviews examples of large-scale diversion incidents and diversion techniques and provides practical strategies to stimulate enhanced CS security within the pharmacy staff. Large-scale diversion from within a pharmacy department can be averted by a pharmacist-in-charge who is informed and proactive in taking effective countermeasures. PMID:24421497

  11. Aspects of pathogen genomics, diversity, epidemiology, vector dynamics, and disease management for a newly emerged disease of potato: zebra chip.

    PubMed

    Lin, Hong; Gudmestad, Neil C

    2013-06-01

    An overview is provided for the aspects of history, biology, genomics, genetics, and epidemiology of zebra chip (ZC), a destructive disease of potato (Solanum tuberosum) that represents a major threat to the potato industries in the United States as well as other potato-production regions in the world. The disease is associated with a gram-negative, phloem-limited, insect-vectored, unculturable prokaryote, 'Candidatus Liberibacter solanacearum', that belongs to the Rhizobiaceae family of α-Proteobacteria. The closest cultivated relatives of 'Ca. L. solanacearum' are members of the group of bacteria known as the α-2 subgroup. In spite of the fact that Koch's postulates sensu stricto have not been fulfilled, a great deal of progress has been made in understanding the ZC disease complex since discovery of the disease. Nevertheless, more research is needed to better understand vector biology, disease mechanisms, host response, and epidemiology in the context of vector-pathogen-plant interactions. Current ZC management strategies focus primarily on psyllid control. The ultimate control of ZC likely relies on host resistance. Unfortunately, all commercial potato cultivars are susceptible to ZC. Elucidation of the 'Ca. L. solanacearum' genome sequence has provided insights into the genetic basis of virulence and physiological and metabolic capability of this organism. Finally, the most effective, sustainable management of ZC is likely to be based on integrated strategies, including removal or reduction of vectors or inocula, improvement of host resistance to the presumptive pathogen and psyllid vectors, and novel gene-based therapeutic treatment. PMID:23268582

  12. Programmable controller system for wind tunnel diversion vanes

    NASA Technical Reports Server (NTRS)

    King, R. F.

    1982-01-01

    A programmable controller (PC) system automatic sequence control, which acts as a supervisory controller for the servos, selects the proper drives, and automatically sequences the vanes, was developed for use in a subsonic wind tunnel. Tunnel modifications include a new second test section (80 ft x 100 ft with a maximum air speed capability of 110 knots) and an increase in maximum velocity flow from 200 knots to 300 knots. A completely automatic sequence control is necessary in order to allow intricate motion of the 14 triangularly arranged vanes which can be as large as 70 ft high x 35 ft wide and which require precise acceleration and deceleration control. Rate servos on each drive aid in this control, and servo cost was minimized by using four silicon controlled rectifier controllers to control the 20 dc drives. The PC has a programming capacity which facilitated the implementation of extensive logic design. A series of diagrams sequencing the vanes and a block diagram of the system are included.

  13. Diverse lamin-dependent mechanisms interact to control chromatin dynamics

    PubMed Central

    Camozzi, Daria; Capanni, Cristina; Cenni, Vittoria; Mattioli, Elisabetta; Columbaro, Marta; Squarzoni, Stefano; Lattanzi, Giovanna

    2014-01-01

    Interconnected functional strategies govern chromatin dynamics in eukaryotic cells. In this context, A and B type lamins, the nuclear intermediate filaments, act on diverse platforms involved in tissue homeostasis. On the nuclear side, lamins elicit large scale or fine chromatin conformational changes, affect DNA damage response factors and transcription factor shuttling. On the cytoplasmic side, bridging-molecules, the LINC complex, associate with lamins to coordinate chromatin dynamics with cytoskeleton and extra-cellular signals. Consistent with such a fine tuning, lamin mutations and/or defects in their expression or post-translational processing, as well as mutations in lamin partner genes, cause a heterogeneous group of diseases known as laminopathies. They include muscular dystrophies, cardiomyopathy, lipodystrophies, neuropathies, and progeroid syndromes. The study of chromatin dynamics under pathological conditions, which is summarized in this review, is shedding light on the complex and fascinating role of the nuclear lamina in chromatin regulation. PMID:25482195

  14. IQGAP1 and Its Binding Proteins Control Diverse Biological Functions

    PubMed Central

    White, Colin D.; Erdemir, Huseyin H.; Sacks, David B.

    2012-01-01

    IQGAP proteins have been identified in a wide spectrum of organisms, ranging from yeast to humans. The most extensively studied family member is the ubiquitously expressed scaffold protein IQGAP1, which participates in multiple essential aspects of mammalian biology. IQGAP1 mediates these effects by binding to and regulating the function of numerous interacting proteins. Over ninety proteins have been reported to associate with IQGAP1, either directly or as part of a larger complex. In this review, we summarise those IQGAP1 binding partners that have been identified in the last five years. The molecular mechanisms by which these interactions contribute to the functions of receptors and their signalling cascades, small GTPase function, cytoskeletal dynamics, neuronal regulation and intracellular trafficking are evaluated. The evidence that has accumulated recently validates the role of IQGAP1 as a scaffold protein and expands the repertoire of cellular activities in which it participates. PMID:22182509

  15. Hot and Cool Aspects of Cognitive Control in Children with ADHD: Decision-Making and Inhibition

    ERIC Educational Resources Information Center

    Geurts, Hilde M.; van der Oord, Saskia; Crone, Eveline A.

    2006-01-01

    This study investigated hot and cool aspects of cognitive control in children with Attention Deficit Hyperactivity Disorder (ADHD). The study aimed to: (1) replicate the postulated response inhibition deficit of children with ADHD; (2) explore whether children with ADHD choose disadvantageously in a decision-making task and to explore the

  16. Lumpy skin disease in southern Africa: a review of the disease and aspects of control.

    PubMed

    Hunter, P; Wallace, D

    2001-06-01

    This article reviews some of the important aspects of lumpy skin disease (LSD) that may impact on its successful control. A resurgence of the disease in the last decade has highlighted some constraints of the Neethling strain vaccine, but there is no evidence of vaccine breakdowns owing to the presence of heterologous field strains. More research is needed on epidemiology and transmission of LSD in South Africa to formulate control measures. PMID:11513262

  17. Learning of Temporal and Spatial Movement Aspects: A Comparison of Four Types of Haptic Control and Concurrent Visual Feedback.

    PubMed

    Rauter, Georg; Sigrist, Roland; Riener, Robert; Wolf, Peter

    2015-01-01

    In literature, the effectiveness of haptics for motor learning is controversially discussed. Haptics is believed to be effective for motor learning in general; however, different types of haptic control enhance different movement aspects. Thus, in dependence on the movement aspects of interest, one type of haptic control may be effective whereas another one is not. Therefore, in the current work, it was investigated if and how different types of haptic controllers affect learning of spatial and temporal movement aspects. In particular, haptic controllers that enforce active participation of the participants were expected to improve spatial aspects. Only haptic controllers that provide feedback about the task's velocity profile were expected to improve temporal aspects. In a study on learning a complex trunk-arm rowing task, the effect of training with four different types of haptic control was investigated: position control, path control, adaptive path control, and reactive path control. A fifth group (control) trained with visual concurrent augmented feedback. As hypothesized, the position controller was most effective for learning of temporal movement aspects, while the path controller was most effective in teaching spatial movement aspects of the rowing task. Visual feedback was also effective for learning temporal and spatial movement aspects. PMID:25974949

  18. Oceanographic controls on the diversity and extinction of planktonic foraminifera.

    PubMed

    Peters, Shanan E; Kelly, Daniel C; Fraass, Andrew J

    2013-01-17

    Understanding the links between long-term biological evolution, the ocean-atmosphere system and plate tectonics is a central goal of Earth science. Although environmental perturbations of many different kinds are known to have affected long-term biological evolution, particularly during major mass extinction events, the relative importance of physical environmental factors versus biological interactions in governing rates of extinction and origination through geological time remains unknown. Here we use macrostratigraphic data from the Atlantic Ocean basin to show that changes in global species diversity and rates of extinction among planktonic foraminifera have been linked to tectonically and climatically forced changes in ocean circulation and chemistry from the Jurassic period to the present. Transient environmental perturbations, such as those that occurred after the asteroid impact at the end of the Cretaceous period approximately 66 million years ago, and the Eocene/Oligocene greenhouse-icehouse transition approximately 34 million years ago, are superimposed on this general long-term relationship. Rates of species origination, by contrast, are not correlated with corresponding macrostratigraphic quantities, indicating that physiochemical changes in the ocean-atmosphere system affect evolution principally by driving the synchronous extinction of lineages that originated owing to more protracted and complex interactions between biological and environmental factors. PMID:23302802

  19. Humboldt's spa: microbial diversity is controlled by temperature in geothermal environments.

    PubMed

    Sharp, Christine E; Brady, Allyson L; Sharp, Glen H; Grasby, Stephen E; Stott, Matthew B; Dunfield, Peter F

    2014-06-01

    Over 200 years ago Alexander von Humboldt (1808) observed that plant and animal diversity peaks at tropical latitudes and decreases toward the poles, a trend he attributed to more favorable temperatures in the tropics. Studies to date suggest that this temperature-diversity gradient is weak or nonexistent for Bacteria and Archaea. To test the impacts of temperature as well as pH on bacterial and archaeal diversity, we performed pyrotag sequencing of 16S rRNA genes retrieved from 165 soil, sediment and biomat samples of 36 geothermal areas in Canada and New Zealand, covering a temperature range of 7.5-99?C and a pH range of 1.8-9.0. This represents the widest ranges of temperature and pH yet examined in a single microbial diversity study. Species richness and diversity indices were strongly correlated to temperature, with R(2) values up to 0.62 for neutral-alkaline springs. The distributions were unimodal, with peak diversity at 24?C and decreasing diversity at higher and lower temperature extremes. There was also a significant pH effect on diversity; however, in contrast to previous studies of soil microbial diversity, pH explained less of the variability (13-20%) than temperature in the geothermal samples. No correlation was observed between diversity values and latitude from the equator, and we therefore infer a direct temperature effect in our data set. These results demonstrate that temperature exerts a strong control on microbial diversity when considered over most of the temperature range within which life is possible. PMID:24430481

  20. Initial Performance of the Attitude Control and Aspect Determination Subsystems on the Chandra Observatory

    NASA Technical Reports Server (NTRS)

    Cameron, R.; Aldcroft, T.; Podgorski, W. A.; Freeman, M. D.

    2000-01-01

    The aspect determination system of the Chandra X-ray Observatory plays a key role in realizing the full potential of Chandra's X-ray optics and detectors. We review the performance of the spacecraft hardware components and sub-systems, which provide information for both real time control of the attitude and attitude stability of the Chandra Observatory and also for more accurate post-facto attitude reconstruction. These flight components are comprised of the aspect camera (star tracker) and inertial reference units (gyros), plus the fiducial lights and fiducial transfer optics which provide an alignment null reference system for the science instruments and X-ray optics, together with associated thermal and structural components. Key performance measures will be presented for aspect camera focal plane data, gyro performance both during stable pointing and during maneuvers, alignment stability and mechanism repeatability.

  1. Genetic diversity analysis of Macaca thibetana based on mitochondrial DNA control region sequences.

    PubMed

    Li, Deming; Fan, Longqin; Ran, Jianghong; Yin, Hailin; Wang, Hongxing; Wu, Shaobin; Yue, Bisong

    2008-10-01

    Macaca thibetana is a threatened primate species endemic to China. Genetic diversities based on a 476-bp fragment at the 5'-end of the mitochondrial DNA control region HVSI were assessed. Haplotype diversity is high (0.8521), but nucleotide diversity among all haplotypes is only 0.0574. No haplotype was shared between Sichuan (SC) and Huangshan Mountain (HS) populations. Phylogenetic trees, analysis of molecular variance and network analysis consistently indicated that the SC and HS populations are significantly different. They should therefore be conserved as different units, with priority and more attention given to the HS populations. PMID:19489138

  2. Operational and research aspects of a radio-controlled model flight test program

    NASA Technical Reports Server (NTRS)

    Budd, Gerald D.; Gilman, Ronald L.; Eichstedt, David

    1993-01-01

    The operational and research aspects of a subscale, radio-controlled model flight test program are presented. By using low-cost free-flying models, an approach was developed for obtaining research-quality vehicle performance and aerodynamic information. The advantages and limitations learned by applying this approach to a specific flight test program are described. The research quality of the data acquired shows that model flight testing is practical for obtaining consistent and repeatable flight data.

  3. Nutritional and cultural aspects of plant species selection for a controlled ecological life support system

    NASA Technical Reports Server (NTRS)

    Hoff, J. E.; Howe, J. M.; Mitchell, C. A.

    1982-01-01

    The feasibility of using higher plants in a controlled ecological life support system is discussed. Aspects of this system considered important in the use of higher plants include: limited energy, space, and mass, and problems relating to cultivation and management of plants, food processing, the psychological impact of vegetarian diets, and plant propagation. A total of 115 higher plant species are compared based on 21 selection criteria.

  4. Top-down control of marine phytoplankton diversity in a global ecosystem model

    NASA Astrophysics Data System (ADS)

    Prowe, A. E. Friederike; Pahlow, Markus; Dutkiewicz, Stephanie; Follows, Michael; Oschlies, Andreas

    2012-08-01

    The potential of marine ecosystems to adapt to ongoing environmental change is largely unknown, making prediction of consequences for nutrient and carbon cycles particularly challenging. Realizing that biodiversity might influence the adaptation potential, recent model approaches have identified bottom-up controls on patterns of phytoplankton diversity regulated by nutrient availability and seasonality. Top-down control of biodiversity, however, has not been considered in depth in such models. Here we demonstrate how zooplankton predation with prey-ratio based food preferences can enhance phytoplankton diversity in a ecosystem-circulation model with self-assembling community structure. Simulated diversity increases more than threefold under preferential grazing relative to standard density-dependent predation, and yields better agreement with observed distributions of phytoplankton diversity. The variable grazing pressure creates refuges for less competitive phytoplankton types, which reduces exclusion and improves the representation of seasonal phytoplankton succession during blooms. The type of grazing parameterization also has a significant impact on primary and net community production. Our results demonstrate how a simple parameterization of a zooplankton community response affects simulated phytoplankton community structure, diversity and dynamics, and motivates development of more detailed representations of top-down processes essential for investigating the role of diversity in marine ecosystems.

  5. Effect of Aspect Ratio on the Low-Speed Lateral Control Characteristics of Untapered Low-Aspect-Ratio Wings Equipped with Flap and with Retractable Ailerons

    NASA Technical Reports Server (NTRS)

    Fischel, Jack; Naeseth, Rodger L; Hagerman, John R; O'Hare, William M

    1952-01-01

    A low-speed wind-tunnel investigation was made to determine the lateral control characteristics of a series of untapered low-aspect-ratio wings. Sealed flap ailerons of various spans and spanwise locations were investigated on unswept wings of aspect ratios 1.13, 1.13, 4.13, and 6.13; and various projections of 0.60-semispan retractable ailerons were investigated on the unsweptback wings of aspect ratios 1.13, 2.13, and 4.13 and on a 45 degree sweptback wing. The retractable ailerons investigated on the unswept wings spanned the outboard stations of each wing; whereas the plain and stepped retractable ailerons investigated on the sweptback wing were located at various spanwise stations. Design charts based on experimental results are presented for estimating the flap aileron effectiveness for low-aspect-ratio, untapered, unswept.

  6. Aspects of pathogen genomics, diversity, epidemiology, vector dynamics and disease management for a newly emerged disease of potato: Zebra Chip

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An overview is provided for the aspects of history, biology, genomics, genetics and epidemiology of zebra chip (ZC), a destructive disease of potato (Solanum tuberosum L.) that represents a major threat to potato industries in the US as well as other potato production regions in the world. The dise...

  7. Improving glycaemic control in children and adolescents: which aspects of therapy really matter?

    PubMed

    Skinner, T C; Cameron, F J

    2010-04-01

    In paediatric diabetes, the concept of intensive therapy in the post-Diabetes Control and Complications Trial period has become subverted by a pharmaco-technological paradigm at the expense of other aspects of care such as goal-setting and psychosocial support. This review examines which patients benefit most from intensive therapy in terms of glycaemic control (HbA1c). It also reviews published controlled trial and observational data relating to the impact of various insulin types and delivery systems on glycaemic control and canvasses the literature dealing with the impact of patient support, philosophy of care, goal setting and treating team dynamic on HbA1c. Taking into account the characteristics of those patients who benefit most from intensive therapy, the quantum of HbA1c change and the persistence of changes that have been reported in selected and non-selected patient groups, it appears that there is a clear hierarchy in aspects of therapy that improve glycaemic control for children and adolescents with Type 1 diabetes. Prime issues appear to be patient support, team cohesion and goal setting. The reported glycaemic benefits achieved by an isolated emphasis upon a pharmaco-technological paradigm are limited in children and adolescents. It appears that only after the prime issues have been first considered will the potential benefits of the insulin types and regimens then be realized. PMID:20536506

  8. Safety aspects of handling and using fecal material from urine-diversion toilets--a field investigation.

    PubMed

    Austin, L M; Cloete, T E

    2008-04-01

    The most advantageous approach to pathogen destruction in a urine-diversion toilet vault is to maximize the effects of various environmental factors (i.e., pH, temperature, moisture content, type of bulking agent, and storage time). To quantify these effects, a field experiment was set up, consisting of 6 urine-diversion toilet vaults, each with a different combination of feces and bulking agent (soil, ash, wood shavings, sodium hydroxide, or straw) and ventilation (ventpipe/no ventpipe). The pH of the mixes varied from 6.37 to 10.09. Temperature probes, which were connected to a data logger, were inserted to the heaps, and the logger monitored over a period of nearly 10 months. Mean heap temperatures ranged from 16.8 degrees C in winter to 27.6 degrees C in summer. In addition, samples were taken at intervals from the various heaps in the vaults and also from an open heap exposed to the elements. The samples were subjected to microbiological testing to quantify the pathogen dieoff over time. In the vaults, there was a 3log10 (99.9%) reduction of total coliform between 130 and 250 days, fecal coliform between 100 and 250 days, and fecal streptococci from 125 days and longer. In the open heap, these times varied, from 115 days for both total and fecal coliform, to 140 days for fecal streptococci. Viable Ascaris ova were reduced to zero between 44 and 174 days in the vaults and by 44 days in the open heap. The results of this research showed that ventilation of the vault by means of a ventpipe does not result in any meaningful difference in the vault temperature or the rate of pathogen dieoff. While the type of bulking agent used does not significantly affect the temperature of the heap, it does have an effect on the rate of pathogen dieoff. The ordinary soil mix was seen to give the best results, and this was ascribed to the effect of competing microorganisms in the soil itself. It is concluded that, for safety, vaults of urine-diversion toilets should be sized for a storage period of 9 to 12 months from the last use. PMID:18536481

  9. Radiation control aspects of the civil construction for a high power free electron laser (FEL) facility

    SciTech Connect

    Dunn, T.; Neil, G.; Stapleton, G.

    1996-12-31

    The paper discusses some of the assumptions and methods employed for the control of ionizing radiation in the specifications for the civil construction of a planned free electron laser facility based on a 200 MeV, 5 mA superconducting recirculation electron accelerator. Consideration is given firstly to the way in which the underlying building configuration and siting aspects were optimized on the basis of the early assumptions of beam loss and radiation goals. The various design requirements for radiation protection are then considered, and how they were folded into an aesthetically pleasing and functional building.

  10. Overview of environmental control aspects for the gas-cooled fast reactor

    SciTech Connect

    Nolan, A.M.

    1981-05-01

    Environmental control aspects relating to release of radionuclides have been analyzed for the Gas-Cooled Fast Reactor (GCFR). Information on environmental control systems was obtained for the most recent GCFR designs, and was used to evaluate the adequacy of these systems. The GCFR has been designed by the General Atomic Company as an alternative to other fast breeder reactor designs, such as the Liquid Metal Fast Breeder Reactor (LMFBR). The GCFR design includes mixed oxide fuel and helium coolant. The environmental impact of expected radionuclide releases from normal operation of the GCFR was evaluated using estimated collective dose equivalent commitments resulting from 1 year of plant operation. The results were compared to equivalent estimates for the Light Water Reactor (LWR) and High-Temperature Gas-Cooled Reactor (HTGR). A discussion of uncertainties in system performances, tritium production rates, and radiation quality factors for tritium is included.

  11. Human factors aspects of the major upgrade to the control systems at the LANL plutonium facility

    SciTech Connect

    Higgins, J.C.; Pope, N.

    1997-04-01

    The Plutonium Facility (TA-55) at Los Alamos National Laboratory (LANL) has been in operation for almost 20 years. The Operations Center of TA-55 is the nerve center of the facility where operators are on duty around the clock and monitor several thousand data points using the Facility Control System (FCS). The FCS monitors, displays, alarms, and provides some limited control of several systems, including: HVAC, fire detection and suppression, radiation detection, and electrical. The FCS was failing and needed to be replaced expeditiously. This paper will discuss the human factors aspects of the design, installation, and testing of the new FCS within the above noted constraints. Particular items to be discussed include the functional requirements definition, operating experience review, screen designs, test program, operator training, and phased activation of the new circuits in an operational facility.

  12. Some aspects of numerical simulation of control valves for steam turbines

    NASA Astrophysics Data System (ADS)

    Hajšman, Martin; Kovandová, Dana; Matas, Richard

    2012-04-01

    The contribution deals with the numerical simulation of air and steam flow through the model of control valve for steam turbines. Numerical simulations were compared with experimental measurements for the award of the same boundary conditions. Valve characteristics have been computed for individual travel heights and pressure ratios of two variants of seat inflow angle (90° and 60°). Some other aspects are discussed in the article - comparison of the axysymmetric and 3D modelling, influence of the computational domain size, comparison of characteristics for two flow media, experimental model of the valve etc. The mentioned results are important for engineering simulations and also for design of the control valves for steam turbines of the large output.

  13. Ecological prevalence, genetic diversity, and epidemiological aspects of Salmonella isolated from tomato agricultural regions of the Virginia Eastern Shore.

    PubMed

    Bell, Rebecca L; Zheng, Jie; Burrows, Erik; Allard, Sarah; Wang, Charles Y; Keys, Christine E; Melka, David C; Strain, Errol; Luo, Yan; Allard, Marc W; Rideout, Steven; Brown, Eric W

    2015-01-01

    Virginia is the third largest producer of fresh-market tomatoes in the United States. Tomatoes grown along the eastern shore of Virginia are implicated almost yearly in Salmonella illnesses. Traceback implicates contamination occurring in the pre-harvest environment. To get a better understanding of the ecological niches of Salmonella in the tomato agricultural environment, a 2-year study was undertaken at a regional agricultural research farm in Virginia. Environmental samples, including tomato (fruit, blossoms, and leaves), irrigation water, surface water and sediment, were collected over the growing season. These samples were analyzed for the presence of Salmonella using modified FDA-BAM methods. Molecular assays were used to screen the samples. Over 1500 samples were tested. Seventy-five samples tested positive for Salmonella yielding over 230 isolates. The most commonly isolated serovars were S. Newport and S. Javiana with pulsed-field gel electrophoresis yielding 39 different patterns. Genetic diversity was further underscored among many other serotypes, which showed multiple PFGE subtypes. Whole genome sequencing (WGS) of several S. Newport isolates collected in 2010 compared to clinical isolates associated with tomato consumption showed very few single nucleotide differences between environmental isolates and clinical isolates suggesting a source link to Salmonella contaminated tomatoes. Nearly all isolates collected during two growing seasons of surveillance were obtained from surface water and sediment sources pointing to these sites as long-term reservoirs for persistent and endemic contamination of this environment. PMID:25999938

  14. Ecological prevalence, genetic diversity, and epidemiological aspects of Salmonella isolated from tomato agricultural regions of the Virginia Eastern Shore

    PubMed Central

    Bell, Rebecca L.; Zheng, Jie; Burrows, Erik; Allard, Sarah; Wang, Charles Y.; Keys, Christine E.; Melka, David C.; Strain, Errol; Luo, Yan; Allard, Marc W.; Rideout, Steven; Brown, Eric W.

    2015-01-01

    Virginia is the third largest producer of fresh-market tomatoes in the United States. Tomatoes grown along the eastern shore of Virginia are implicated almost yearly in Salmonella illnesses. Traceback implicates contamination occurring in the pre-harvest environment. To get a better understanding of the ecological niches of Salmonella in the tomato agricultural environment, a 2-year study was undertaken at a regional agricultural research farm in Virginia. Environmental samples, including tomato (fruit, blossoms, and leaves), irrigation water, surface water and sediment, were collected over the growing season. These samples were analyzed for the presence of Salmonella using modified FDA-BAM methods. Molecular assays were used to screen the samples. Over 1500 samples were tested. Seventy-five samples tested positive for Salmonella yielding over 230 isolates. The most commonly isolated serovars were S. Newport and S. Javiana with pulsed-field gel electrophoresis yielding 39 different patterns. Genetic diversity was further underscored among many other serotypes, which showed multiple PFGE subtypes. Whole genome sequencing (WGS) of several S. Newport isolates collected in 2010 compared to clinical isolates associated with tomato consumption showed very few single nucleotide differences between environmental isolates and clinical isolates suggesting a source link to Salmonella contaminated tomatoes. Nearly all isolates collected during two growing seasons of surveillance were obtained from surface water and sediment sources pointing to these sites as long-term reservoirs for persistent and endemic contamination of this environment. PMID:25999938

  15. Consumer versus resource control of producer diversity depends on ecosystem type and producer community structure

    PubMed Central

    Hillebrand, Helmut; Gruner, Daniel S.; Borer, Elizabeth T.; Bracken, Matthew E. S.; Cleland, Elsa E.; Elser, James J.; Harpole, W. Stanley; Ngai, Jacqueline T.; Seabloom, Eric W.; Shurin, Jonathan B.; Smith, Jennifer E.

    2007-01-01

    Consumer and resource control of diversity in plant communities have long been treated as alternative hypotheses. However, experimental and theoretical evidence suggests that herbivores and nutrient resources interactively regulate the number and relative abundance of coexisting plant species. Experiments have yielded divergent and often contradictory responses within and among ecosystems, and no effort has to date reconciled this empirical variation within a general framework. Using data from 274 experiments from marine, freshwater, and terrestrial ecosystems, we present a cross-system analysis of producer diversity responses to local manipulations of resource supply and/or herbivory. Effects of herbivory and fertilization on producer richness differed substantially between systems: (i) herbivores reduced species richness in freshwater but tended to increase richness in terrestrial systems; (ii) fertilization increased richness in freshwater systems but reduced richness on land. Fertilization consistently reduced evenness, whereas herbivores increased evenness only in marine and terrestrial ecosystems. Producer community evenness and ecosystem productivity mediated fertilization and herbivore effects on diversity across ecosystems. Herbivores increased producer richness in more productive habitats and in producer assemblages with low evenness. These same assemblages also showed the strongest reduction in richness with fertilization, whereas fertilization increased (and herbivory decreased) richness in producer assemblages with high evenness. Our study indicates that system productivity and producer evenness determine the direction and magnitude of top-down and bottom-up control of diversity and may reconcile divergent empirical results within and among ecosystems. PMID:17581875

  16. Sex differences in neurophysiological responses are modulated by attentional aspects of impulse control.

    PubMed

    Omura, Kazufumi; Kusumoto, Kenji

    2015-11-01

    The amplitudes of the N2 and P3 components of event-related potentials (ERPs) may be influenced by personality traits such as impulsivity, and male/female differences may also have an effect. However, few studies have assessed the interaction between personality traits and the sex of the subject in these components. Therefore, in this study we evaluated sex differences in the amplitudes of the N2 and P3 ERP components during a continuous performance task, and their relation to impulse control. Twenty-seven healthy participants were asked to perform an AX-type continuous performance task, also known as a Go/Nogo task, during electroencephalographic recording. Participants then completed the Barratt impulsiveness scale (version 11; BIS-11), and the effortful control (EC) scale to self-report personality measures related to impulse control. We found that in the Nogo condition, males showed significantly larger N2 amplitudes than females in the frontal area. Interestingly, Nogo-N2 amplitudes were positively correlated with BIS-attentional subscale scores, but were negatively correlated with EC-attentional subscale scores, and both correlations were observed only in males. These results suggest that attentional aspects of impulse control modulate Nogo-N2 amplitude only in males. This modulatory effect may be related to a sex-specific inhibitory control mechanism acting during early stimulus evaluation. PMID:26473554

  17. Access and benefit sharing (ABS) under the convention on biological diversity (CBD): implications for microbial biological control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Researchers and implementers of biological control are confronted with a variety of scientific, regulatory and administrative challenges to their biological control programs. One developing challenge will arise from the implementation of provisions of the Convention on Biological Diversity (CBD) co...

  18. Psychological Aspects in Children and Adolescents With Major Thalassemia: A Case-Control Study

    PubMed Central

    Behdani, Fatemeh; Badiee, Zahra; Hebrani, Paria; Moharreri, Fatemeh; Badiee, Amir Hossein; Hajivosugh, Negin; Rostami, Zohreh; Akhavanrezayat, Amir

    2015-01-01

    Background: Thalassemia is an inherited blood disease. It is a serious public health problem throughout the Mediterranean region, the Middle East and the Indian subcontinent, as well as in Southeast Asia. Objectives: Thalassemia is an inherited blood disease. It is a serious public health problem. In this study we assessed psychological aspects in Iranian children and adolescents with thalassemia major. Patients and Methods: In this case-control study sixty healthy subjects aged 7-18 years and Sixty Patients with confirmed diagnosis of major thalassemia were enrolled. After obtaining informed consent from parents of all participating thalassemia patients and healthycontrols, we assessed psychological aspects and quality of life by Pediatric Quality of LifeTM (PedsQL), Strengths and Difficulties Questionnaires (SDQ), State and Trait Anxiety, Children's Depression Inventory (CDI). Results: The results of this study indicate that there are significant changes in depression, anxiety, QOL and behavioral screening between children with thalassemia major compared with healthy subjects by means of both parents and children reports. According to the results, children with thalassemia major have more psychological problems than healthy ones. Patients with thalassemia have a lower QOL than their peers (P = 0.001), the rate of depression is higher in this group (P = 0.015), Also behavioral problems in these children are more than healthy subjects (P = 0.009). Conclusions: We recommend appropriate treatment and counseling procedures in addition to specific treatment of thalassemia. According to the results we suggest to establish pediatric psychiatric clinics beside thalassemic clinics to cure psychological aspects of the disease. PMID:26199704

  19. Farm management, not soil microbial diversity, controls nutrient loss from smallholder tropical agriculture

    PubMed Central

    Wood, Stephen A.; Almaraz, Maya; Bradford, Mark A.; McGuire, Krista L.; Naeem, Shahid; Neill, Christopher; Palm, Cheryl A.; Tully, Katherine L.; Zhou, Jizhong

    2015-01-01

    Tropical smallholder agriculture is undergoing rapid transformation in nutrient cycling pathways as international development efforts strongly promote greater use of mineral fertilizers to increase crop yields. These changes in nutrient availability may alter the composition of microbial communities with consequences for rates of biogeochemical processes that control nutrient losses to the environment. Ecological theory suggests that altered microbial diversity will strongly influence processes performed by relatively few microbial taxa, such as denitrification and hence nitrogen losses as nitrous oxide, a powerful greenhouse gas. Whether this theory helps predict nutrient losses from agriculture depends on the relative effects of microbial community change and increased nutrient availability on ecosystem processes. We find that mineral and organic nutrient addition to smallholder farms in Kenya alters the taxonomic and functional diversity of soil microbes. However, we find that the direct effects of farm management on both denitrification and carbon mineralization are greater than indirect effects through changes in the taxonomic and functional diversity of microbial communities. Changes in functional diversity are strongly coupled to changes in specific functional genes involved in denitrification, suggesting that it is the expression, rather than abundance, of key functional genes that can serve as an indicator of ecosystem process rates. Our results thus suggest that widely used broad summary statistics of microbial diversity based on DNA may be inappropriate for linking microbial communities to ecosystem processes in certain applied settings. Our results also raise doubts about the relative control of microbial composition compared to direct effects of management on nutrient losses in applied settings such as tropical agriculture. PMID:25926815

  20. Farm management, not soil microbial diversity, controls nutrient loss from smallholder tropical agriculture.

    PubMed

    Wood, Stephen A; Almaraz, Maya; Bradford, Mark A; McGuire, Krista L; Naeem, Shahid; Neill, Christopher; Palm, Cheryl A; Tully, Katherine L; Zhou, Jizhong

    2015-01-01

    Tropical smallholder agriculture is undergoing rapid transformation in nutrient cycling pathways as international development efforts strongly promote greater use of mineral fertilizers to increase crop yields. These changes in nutrient availability may alter the composition of microbial communities with consequences for rates of biogeochemical processes that control nutrient losses to the environment. Ecological theory suggests that altered microbial diversity will strongly influence processes performed by relatively few microbial taxa, such as denitrification and hence nitrogen losses as nitrous oxide, a powerful greenhouse gas. Whether this theory helps predict nutrient losses from agriculture depends on the relative effects of microbial community change and increased nutrient availability on ecosystem processes. We find that mineral and organic nutrient addition to smallholder farms in Kenya alters the taxonomic and functional diversity of soil microbes. However, we find that the direct effects of farm management on both denitrification and carbon mineralization are greater than indirect effects through changes in the taxonomic and functional diversity of microbial communities. Changes in functional diversity are strongly coupled to changes in specific functional genes involved in denitrification, suggesting that it is the expression, rather than abundance, of key functional genes that can serve as an indicator of ecosystem process rates. Our results thus suggest that widely used broad summary statistics of microbial diversity based on DNA may be inappropriate for linking microbial communities to ecosystem processes in certain applied settings. Our results also raise doubts about the relative control of microbial composition compared to direct effects of management on nutrient losses in applied settings such as tropical agriculture. PMID:25926815

  1. Optical communication through the turbulent atmosphere with transmitter and receiver diversity, wavefront control, and coherent detection

    NASA Astrophysics Data System (ADS)

    Puryear, Andrew L.; Chan, Vincent W. S.

    2009-08-01

    Net-centric warfare in todays dynamically changing military environments and the need for low-cost gigabit intra-city communication present severe challenges for current free-space optical systems. Enabled by high-speed electronics and advances in wavefront control, we develop an architecture that provides free-space coherent optical links with information capacity, security, network robustness and power management performance that exceed the current state-of-the-art, including commercially deployed systems, R&D test-beds, and alternative theoretical architectures proposed. The deleterious effects of the turbulent atmosphere are mitigated with several diversity transmitters and receivers. We allow the phase and the amplitude of each transmitter to be controlled independently and assume, through coherent detection, that the phase and amplitude of the received wave is measured. Thus we can optimally allocate transmit power into the diffraction modes with the smallest propagation losses to increase channel capacity and mitigate turbulence-induced outages. Additionally, spatial mode modulation and rejection provides robust communication in the presence of denial of service via interference by adversaries with a priori knowledge of the system architecture. Some possible implementations of this system are described. New results, including asymptotic singular value distribution, expected bit error rate, interference performance, and performance in the presence of inhomogeneous turbulence, are given. Finally, performance of this system is compared with the performance of optical diversity systems without wavefront control and optical systems without diversity, both current state-of-the-art systems.

  2. Microbial mat controls on infaunal abundance and diversity in modern marine microbialites.

    PubMed

    Tarhan, L G; Planavsky, N J; Laumer, C E; Stolz, J F; Reid, R P

    2013-09-01

    Microbialites are the most abundant macrofossils of the Precambrian. Decline in microbialite abundance and diversity during the terminal Proterozoic and early Phanerozoic has historically been attributed to the concurrent radiation of complex metazoans. Similarly, the apparent resurgence of microbialites in the wake of Paleozoic and Mesozoic mass extinctions is frequently linked to drastic declines in metazoan diversity and abundance. However, it has become increasing clear that microbialites are relatively common in certain modern shallow, normal marine carbonate environments-foremost the Bahamas. For the first time, we present data, collected from the Exuma Cays, the Bahamas, systematically characterizing the relationship between framework-building cyanobacteria, microbialite fabrics, and microbialite-associated metazoan abundance and diversity. We document the coexistence of diverse microbialite and infaunal metazoan communities and demonstrate that the predominant control upon both microbialite fabric and metazoan community structure is microbial mat type. These findings necessitate that we rethink prevalent interpretations of microbialite-metazoan interactions and imply that microbialites are not passive recipients of metazoan-mediated alteration. Additionally, this work provides support for the theory that certain Precambrian microbialites may have been havens of early complex metazoan life, rather than bereft of metazoans, as has been traditionally envisaged. PMID:23889904

  3. CYFIP dependent actin remodeling controls specific aspects of Drosophila eye morphogenesis.

    PubMed

    Galy, Anne; Schenck, Annette; Sahin, H Bahar; Qurashi, Abrar; Sahel, Jos-Alain; Diebold, Cline; Giangrande, Angela

    2011-11-01

    Cell rearrangements shape organs and organisms using molecular pathways and cellular processes that are still poorly understood. Here we investigate the role of the Actin cytoskeleton in the formation of the Drosophila compound eye, which requires extensive remodeling and coordination between different cell types. We show that CYFIP/Sra-1, a member of the WAVE/SCAR complex and regulator of Actin remodeling, controls specific aspects of eye architecture: rhabdomere extension, rhabdomere terminal web organization, adherens junctions, retina depth and basement membrane integrity. We demonstrate that some phenotypes manifest independently, due to defects in different cell types. Mutations in WAVE/SCAR and in ARP2/3 complex subunits but not in WASP, another major regulator of Actin nucleation, phenocopy CYFIP defects. Thus, the CYFIP-SCAR-ARP2/3 pathway orchestrates specific tissue remodeling processes. PMID:21884694

  4. Design aspects of long range supersonic LFC airplanes with highly swept wings. [laminar flow control

    NASA Technical Reports Server (NTRS)

    Pfenninger, W.; Vemuru, C. S.

    1990-01-01

    Studies on supersonic long-range LFC (laminar flow control) aircraft were performed with the aim of maximizing L/D and alleviating sonic boom during supersonic cruise. It is found that configurations with highly swept LFC wings of very high structural aspect ratio, with the sweep increasing toward the wing root and braced externally by wide chord laminarized struts, appear especially promising. In the supersonic cruise design condition the wing upper surface isobars are swept such that the flow in the direction normal to them is transonic with embedded supersonic zones and practically shock-free over most of the span, with M-perpendicular equal to the two-dimensional design values of advanced SC LFC airfoils, e.g., of the X-787 or X-6 type.

  5. Treg Cells, Life History, and Diversity

    PubMed Central

    Benoist, Christophe; Mathis, Diane

    2012-01-01

    Regulatory T cells expressing the FoxP3 transcription factor have a profound and nonredundant role in several aspects of immunological tolerance. We will review here the specification of this lineage, its population dynamics, and the diversity of subphenotypes that correlate with their diverse roles in controlling inflammation in a variety of settings. PMID:22952391

  6. Increasing zooplankton size diversity enhances the strength of top-down control on phytoplankton through diet niche partitioning.

    PubMed

    Ye, Lin; Chang, Chun-Yi; Garca-Comas, Carmen; Gong, Gwo-Ching; Hsieh, Chih-Hao

    2013-09-01

    1. The biodiversity-ecosystem functioning debate is a central topic in ecology. Recently, there has been a growing interest in size diversity because body size is sensitive to environmental changes and is one of the fundamental characteristics of organisms linking many ecosystem properties. However, how size diversity affects ecosystem functioning is an important yet unclear issue. 2. To fill the gap, with large-scale field data from the East China Sea, we tested the novel hypothesis that increasing zooplankton size diversity enhances top-down control on phytoplankton (H1) and compared it with five conventional hypotheses explaining the top-down control: flatter zooplankton size spectrum enhances the strength of top-down control (H2); nutrient enrichment lessens the strength of top-down control (H3); increasing zooplankton taxonomic diversity enhances the strength of top-down control (H4); increasing fish predation decreases the strength of top-down control of zooplankton on phytoplankton through trophic cascade (H5); increasing temperature intensifies the strength of top-down control (H6). 3. The results of univariate analyses support the hypotheses based on zooplankton size diversity (H1), zooplankton size spectrum (H2), nutrient (H3) and zooplankton taxonomic diversity (H4), but not the hypotheses based on fish predation (H5) and temperature (H6). More in-depth analyses indicate that zooplankton size diversity is the most important factor in determining the strength of top-down control on phytoplankton in the East China Sea. 4. Our results suggest a new potential mechanism that increasing predator size diversity enhances the strength of top-down control on prey through diet niche partitioning. This mechanism can be explained by the optimal predator-prey body-mass ratio concept. Suppose each size group of zooplankton predators has its own optimal phytoplankton prey size, increasing size diversity of zooplankton would promote diet niche partitioning of predators and thus elevates the strength of top-down control. PMID:23506226

  7. Physicochemical control of bacterial and protist community composition and diversity in Antarctic sea ice.

    PubMed

    Torstensson, Anders; Dinasquet, Julie; Chierici, Melissa; Fransson, Agneta; Riemann, Lasse; Wulff, Angela

    2015-10-01

    Due to climate change, sea ice experiences changes in terms of extent and physical properties. In order to understand how sea ice microbial communities are affected by changes in physicochemical properties of the ice, we used 454-sequencing of 16S and 18S rRNA genes to examine environmental control of microbial diversity and composition in Antarctic sea ice. We observed a high diversity and richness of bacteria, which were strongly negatively correlated with temperature and positively with brine salinity. We suggest that bacterial diversity in sea ice is mainly controlled by physicochemical properties of the ice, such as temperature and salinity, and that sea ice bacterial communities are sensitive to seasonal and environmental changes. For the first time in Antarctic interior sea ice, we observed a strong eukaryotic dominance of the dinoflagellate phylotype SL163A10, comprising 63% of the total sequences. This phylotype is known to be kleptoplastic and could be a significant primary producer in sea ice. We conclude that mixotrophic flagellates may play a greater role in the sea ice microbial ecosystem than previously believed, and not only during the polar night but also during summer when potential food sources are abundant. PMID:25845501

  8. Aspects regarding at 13C isotope separation column control using Petri nets system

    NASA Astrophysics Data System (ADS)

    Boca, M. L.; Ciortea, M. E.

    2015-11-01

    This paper is intended to show that Petri nets can be also applicable in the chemical industry. It used linear programming, modeling underlying Petri nets, especially discrete event systems for isotopic separation, the purpose of considering and control events in real-time through graphical representations. In this paper it is simulate the control of 13C Isotope Separation column using Petri nets. The major problem with 13C comes from the difficulty of obtaining it and raising its natural fraction. Carbon isotopes can be obtained using many methods, one of them being the cryogenic distillation of carbon monoxide. Some few aspects regarding operating conditions and the construction of such cryogenic plants are known today, and even less information are available as far as the separation process modeling and control are concerned. In fact, the efficient control of the carbon monoxide distillation process represents a necessity for large-scale 13C production. Referring to a classic distillation process, some models for carbon isotope separation have been proposed, some based on mass, component and energy balance equations, some on the nonlinear wave theory or the Cohen equations. For modeling the system it was used Petri nets because in this case it is deal with discrete event systems. In use of the non-timed and with auxiliary times Petri model, the transport stream was divided into sections and these sections will be analyzed successively. Because of the complexity of the system and the large amount of calculations required it was not possible to analyze the system as a unitary whole. A first attempt to model the system as a unitary whole led to the blocking of the model during simulation, because of the large processing times.

  9. Cyber-Physical Geographical Information Service-Enabled Control of Diverse In-Situ Sensors

    PubMed Central

    Chen, Nengcheng; Xiao, Changjiang; Pu, Fangling; Wang, Xiaolei; Wang, Chao; Wang, Zhili; Gong, Jianya

    2015-01-01

    Realization of open online control of diverse in-situ sensors is a challenge. This paper proposes a Cyber-Physical Geographical Information Service-enabled method for control of diverse in-situ sensors, based on location-based instant sensing of sensors, which provides closed-loop feedbacks. The method adopts the concepts and technologies of newly developed cyber-physical systems (CPSs) to combine control with sensing, communication, and computation, takes advantage of geographical information service such as services provided by the Tianditu which is a basic geographic information service platform in China and Sensor Web services to establish geo-sensor applications, and builds well-designed human-machine interfaces (HMIs) to support online and open interactions between human beings and physical sensors through cyberspace. The method was tested with experiments carried out in two geographically distributed scientific experimental fields, Baoxie Sensor Web Experimental Field in Wuhan city and Yemaomian Landslide Monitoring Station in Three Gorges, with three typical sensors chosen as representatives using the prototype system Geospatial Sensor Web Common Service Platform. The results show that the proposed method is an open, online, closed-loop means of control. PMID:25625906

  10. Cyber-physical geographical information service-enabled control of diverse in-situ sensors.

    PubMed

    Chen, Nengcheng; Xiao, Changjiang; Pu, Fangling; Wang, Xiaolei; Wang, Chao; Wang, Zhili; Gong, Jianya

    2015-01-01

    Realization of open online control of diverse in-situ sensors is a challenge. This paper proposes a Cyber-Physical Geographical Information Service-enabled method for control of diverse in-situ sensors, based on location-based instant sensing of sensors, which provides closed-loop feedbacks. The method adopts the concepts and technologies of newly developed cyber-physical systems (CPSs) to combine control with sensing, communication, and computation, takes advantage of geographical information service such as services provided by the Tianditu which is a basic geographic information service platform in China and Sensor Web services to establish geo-sensor applications, and builds well-designed human-machine interfaces (HMIs) to support online and open interactions between human beings and physical sensors through cyberspace. The method was tested with experiments carried out in two geographically distributed scientific experimental fields, Baoxie Sensor Web Experimental Field in Wuhan city and Yemaomian Landslide Monitoring Station in Three Gorges, with three typical sensors chosen as representatives using the prototype system Geospatial Sensor Web Common Service Platform. The results show that the proposed method is an open, online, closed-loop means of control. PMID:25625906

  11. The supply chain of medicinal controlled substances: addressing the Achilles heel of drug diversion.

    PubMed

    Coleman, John J

    2012-09-01

    The escalation of prescription drug abuse in the U.S. has attracted the attention of public health and safety officials as well as others puzzled by how such a tightly regulated enterprise could so easily be breached by those seeking controlled substances for nonmedical use. Prescribers and patients who use, misuse, or, in some cases, redistribute or divert these drugs have figured prominently in government strategies aimed at addressing this issue. This review departs from this paradigm and focuses on wholesale drug distributors, a highly efficient and largely behinds-the-scene link in the supply chain of controlled substances. By law, distributors are required to identify and report to the Drug Enforcement Administration (DEA) orders for controlled substances that are suspicious and may indicate drug diversion. Ten cases are examined in which distributors were each charged with failing to prevent the diversion of millions of doses of controlled substances. Special attention is given to a payment system employed by the industry that may encourage this unlawful commerce. Court records, agency and industry reports, and other published sources are used to document referenced cases and their disposition, and recommendations are offered for improving distributors' compliance with the law. PMID:22973912

  12. Passive control of roll oscillations of low-aspect-ratio wings using bleed

    NASA Astrophysics Data System (ADS)

    Hu, T.; Wang, Z.; Gursul, I.

    2014-06-01

    A passive flow control method, which uses bleed from a slot near the wing tip, has been shown to attenuate self-excited roll oscillations of a low-aspect-ratio (AR = 2) rectangular flat plate wing. This method was found to be successful across the whole range of angle of attack and better than previous active flow control methods. The effectiveness of the slot strongly depends on its location and width. For effective slot geometries, the tip vortex becomes less coherent, almost eliminating the roll oscillations. Nonlinear interactions between the shear layers shed from the tip and the slot, as well as between the shear layer and the counter-rotating vortex may act as excitation, which can modify the response of the self-sustained oscillator. When the slot is located too close to the tip, there is rapid merging of the shear layers and less interaction, and the slot loses its effectiveness. Also, when the slot is narrow, there is insufficient bleed, resulting in less effective attenuation. Force measurements revealed that this technique can be used as an effective method to suppress roll oscillations without sacrificing and possibly improving aerodynamic performance.

  13. Adaptive AFM scan speed control for high aspect ratio fast structure tracking

    SciTech Connect

    Ahmad, Ahmad; Schuh, Andreas; Rangelow, Ivo W.

    2014-10-15

    Improved imaging rates in Atomic Force Microscopes (AFM) are of high interest for disciplines such as life sciences and failure analysis of semiconductor wafers, where the sample topology shows high aspect ratios. Also, fast imaging is necessary to cover a large surface under investigation in reasonable times. Since AFMs are composed of mechanical components, they are associated with comparably low resonance frequencies that undermine the effort to increase the acquisition rates. In particular, high and steep structures are difficult to follow, which causes the cantilever to temporarily loose contact to or crash into the sample. Here, we report on a novel approach that does not affect the scanner dynamics, but adapts the lateral scanning speed of the scanner. The controller monitors the control error signal and, only when necessary, decreases the scan speed to allow the z-piezo more time to react to changes in the sample's topography. In this case, the overall imaging rate can be significantly increased, because a general scan speed trade-off decision is not needed and smooth areas are scanned fast. In contrast to methods trying to increase the z-piezo bandwidth, our method is a comparably simple approach that can be easily adapted to standard systems.

  14. Cellulosic fibers with high aspect ratio from cornhusks via controlled swelling and alkaline penetration.

    PubMed

    Ma, Zhuanzhuan; Pan, Gangwei; Xu, Helan; Huang, Yiling; Yang, Yiqi

    2015-06-25

    Cellulosic fibers with high aspect ratio have been firstly obtained from cornhusks via controlled swelling in organic solvent and simultaneous tetramethylammonium hydroxide (TMAOH) post treatment within restricted depth. Cornhusks, with around 42% cellulose content, are a copious and inexpensive source for natural fibers. However, cornhusk fibers at 20tex obtained via small-molecule alkaline extraction were too coarse for textile applications. Continuous NaOH treatment would result in fine fibers but with length of about 0.5-1.5mm, too short for textile use. In this research, post treatment using TMAOH and under controlled swelling significantly reduced fineness of cornhusk fibers from 21.32.88 to 5.720.21tex. Fiber length was reduced from 105.4710.03 to47.227.4mm. The cornhusk fibers had more oriented microstructures and cellulose content increased to 84.47%. Besides, cornhusk fibers had similar tenacity, longer elongation, and lower modulus compared to cotton and linen, which endowed them with durability and flexibility. PMID:25839793

  15. Using Opposing Slope Aspects to Understand Water and Energy Flow Controls on Critical Zone Architecture

    NASA Astrophysics Data System (ADS)

    Anderson, S. P.; Barnhart, K. R.; Kelly, P. K.; Foster, M. A.; Langston, A. L.

    2014-12-01

    A long-standing problem is to understand how climate controls the structure of the critical zone, including the depth of weathering, thickness and character of soils, and morphology of hillslopes. We exploit microclimates on opposing aspects in a watershed in the Boulder Creek CZO to investigate the role of water and energy fluxes on development of critical zone architectures. The 2.6 km2 Gordon Gulch, located at ~2500 m a.s.l. at 40N latitude, is elongated east-west, and consequently is predominantly composed of north and south-facing soil-mantled slopes, dotted with tors, developed on Precambrian gneiss. The depth to fresh rock ranges from about 8 to 12 m, and is up to 2 m deeper on north-facing slopes. In addition to greater thickness, weathered rock is measurably lower in tensile strength on north-facing slopes. While characteristics of weathered rock vary with aspect, the overlying mobile regolith is relatively uniform in thickness at ~0.5 m across the catchment, and its mineralogy shows only minor chemical alteration from parent rock. These features of the critical zone architecture arise in the face of systematic differences in energy and water delivery by aspect. About 40-50% of the ~500 mm annual precipitation is delivered as snow. During spring, the south-facing slopes receive up to 50% greater direct solar radiation than the north-facing slopes. Consequently, snow cover is ephemeral in the open Ponderosa forests on south-facing slopes, and soil wetting and drying events are frequent. Frost penetration is shallow, and short lived. On north-facing slopes, less direct radiation and a dense Lodgepole pine forest cover leads to snowpack retention. Soils are colder and soil moisture stays elevated for long periods in spring on these slopes. We postulate that deeper and more sustained frost penetration on north-facing slopes enhances the damage rate by frost cracking. Deeper water delivery further aids this process, and supports chemical alteration processes. The uniformity of mobile regolith depths suggests equal mobility on these slopes despite differing conditions.

  16. Response of pest control by generalist predators to local-scale plant diversity: a meta-analysis.

    PubMed

    Dassou, Anicet Gbèblonoudo; Tixier, Philippe

    2016-02-01

    Disentangling the effects of plant diversity on the control of herbivores is important for understanding agricultural sustainability. Recent studies have investigated the relationships between plant diversity and arthropod communities at the landscape scale, but few have done so at the local scale. We conducted a meta-analysis of 32 papers containing 175 independent measures of the relationship between plant diversity and arthropod communities. We found that generalist predators had a strong positive response to plant diversity, that is, their abundance increased as plant diversity increased. Herbivores, in contrast, had an overall weak and negative response to plant diversity. However, specialist and generalist herbivores differed in their response to plant diversity, that is, the response was negative for specialists and not significant for generalists. While the effects of scale remain unclear, the response to plant diversity tended to increase for specialist herbivores, but decrease for generalist herbivores as the scale increased. There was no clear effect of scale on the response of generalist predators to plant diversity. Our results suggest that the response of herbivores to plant diversity at the local scale is a balance between habitat and trophic effects that vary according to arthropod specialization and habitat type. Synthesis and applications. Positive effects of plant diversity on generalist predators confirm that, at the local scale, plant diversification of agroecosystems is a credible and promising option for increasing pest regulation. Results from our meta-analysis suggest that natural control in plant-diversified systems is more likely to occur for specialist than for generalist herbivores. In terms of pest management, our results indicate that small-scale plant diversification (via the planting of cover crops or intercrops and reduced weed management) is likely to increase the control of specialist herbivores by generalist predators. PMID:26839684

  17. Chaotic aspects of lasers with host-induced nonlinearity and its control

    NASA Astrophysics Data System (ADS)

    Banerjee, Santo; Saha, Papri; Chowdhury, A. Roy

    2001-12-01

    Recently, absolute instabilities were analysed in lasers that contain a dispersive host material with cubic nonlinearities, which leads to self-phase modulation (SPM) and intensity-dependent absorption (IDA). Nonlinear equations governing the operation of these new kind of lasers are known to possess certain new kind of features not described by the usual Lorenz-Haken dynamics. These nonlinear equations were derived from the Maxwell-Bloch equations and the stability equations were investigated by performing a linear stability analysis by Tartwijk and Agarwal. We try to explore the whole nonlinear region of the system which shows a period doubling route to chaos. The chaotic region is described through phase space diagrams, Lyapunov exponents, temporal variation of predictability and local divergence behaviour. Different aspects of the chaotic attractor reconstructed by the method of time delays, proposed by Takens, is discussed in the light of recurrence plot analysis leading to explicit information about embedding dimension and entropy of line distribution. We implement adaptive and threshold control mechanisms to revert back to a stable configuration of the system.

  18. Composition, taxonomy and functional diversity of the oropharynx microbiome in individuals with schizophrenia and controls

    PubMed Central

    Bendall, Matthew L.; Pérez-Losada, Marcos; Sabuncyan, Sarven; Severance, Emily G.; Dickerson, Faith B.; Schroeder, Jennifer R.; Yolken, Robert H.; Crandall, Keith A.

    2015-01-01

    The role of the human microbiome in schizophrenia remains largely unexplored. The microbiome has been shown to alter brain development and modulate behavior and cognition in animals through gut-brain connections, and research in humans suggests that it may be a modulating factor in many disorders. This study reports findings from a shotgun metagenomic analysis of the oropharyngeal microbiome in 16 individuals with schizophrenia and 16 controls. High-level differences were evident at both the phylum and genus levels, with Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria dominating both schizophrenia patients and controls, and Ascomycota being more abundant in schizophrenia patients than controls. Controls were richer in species but less even in their distributions, i.e., dominated by fewer species, as opposed to schizophrenia patients. Lactic acid bacteria were relatively more abundant in schizophrenia, including species of Lactobacilli and Bifidobacterium, which have been shown to modulate chronic inflammation. We also found Eubacterium halii, a lactate-utilizing species. Functionally, the microbiome of schizophrenia patients was characterized by an increased number of metabolic pathways related to metabolite transport systems including siderophores, glutamate, and vitamin B12. In contrast, carbohydrate and lipid pathways and energy metabolism were abundant in controls. These findings suggest that the oropharyngeal microbiome in individuals with schizophrenia is significantly different compared to controls, and that particular microbial species and metabolic pathways differentiate both groups. Confirmation of these findings in larger and more diverse samples, e.g., gut microbiome, will contribute to elucidating potential links between schizophrenia and the human microbiota. PMID:26336637

  19. Parasitoid diversity reduces the variability in pest control services across time on farms

    PubMed Central

    Macfadyen, Sarina; Craze, Paul G.; Polaszek, Andrew; van Achterberg, Kees; Memmott, Jane

    2011-01-01

    Recent declines in biodiversity have increased interest in the link between biodiversity and the provision and sustainability of ecosystem services across space and time. We mapped the complex network of interactions between herbivores and parasitoids to examine the relationship between parasitoid species richness, functional group diversity and the provision of natural pest control services. Quantitative food webs were constructed for 10 organic and 10 conventional farms. Parasitoid species richness varied from 26 to 58 species and we found a significant positive relationship between parasitoid species richness and temporal stability in parasitism rates. Higher species richness was associated with lower variation in parasitism rate. A functional group analysis showed significantly greater parasitoid species complementarity on organic farms, with on average more species in each functional group. We simulated parasitoid removal to predict whether organic farms experienced greater robustness of parasitism in the face of local extinctions. This analysis showed no consistent differences between the organic and conventional farm pairs in terms of loss of pest control service. Finally, it was found that the different habitats that make up each farm do not contribute equally to parasitoid species diversity, and that hedgerows produced more parasitoid species, significantly more so on organic farms. PMID:21450736

  20. Parasitoid diversity reduces the variability in pest control services across time on farms.

    PubMed

    Macfadyen, Sarina; Craze, Paul G; Polaszek, Andrew; van Achterberg, Kees; Memmott, Jane

    2011-11-22

    Recent declines in biodiversity have increased interest in the link between biodiversity and the provision and sustainability of ecosystem services across space and time. We mapped the complex network of interactions between herbivores and parasitoids to examine the relationship between parasitoid species richness, functional group diversity and the provision of natural pest control services. Quantitative food webs were constructed for 10 organic and 10 conventional farms. Parasitoid species richness varied from 26 to 58 species and we found a significant positive relationship between parasitoid species richness and temporal stability in parasitism rates. Higher species richness was associated with lower variation in parasitism rate. A functional group analysis showed significantly greater parasitoid species complementarity on organic farms, with on average more species in each functional group. We simulated parasitoid removal to predict whether organic farms experienced greater robustness of parasitism in the face of local extinctions. This analysis showed no consistent differences between the organic and conventional farm pairs in terms of loss of pest control service. Finally, it was found that the different habitats that make up each farm do not contribute equally to parasitoid species diversity, and that hedgerows produced more parasitoid species, significantly more so on organic farms. PMID:21450736

  1. Biocontrol of fouling pests: Effect of diversity, identity and density of control agents.

    PubMed

    Atalah, Javier; Newcombe, Emma M; Zaiko, Anastasija

    2016-04-01

    Augmentative biocontrol, using native natural enemies, has been suggested as a promising tool to control marine biofouling pests on artificial structures. However, there are still important knowledge gaps to be addressed before biocontrol can be considered as a management tool. In a field experiment on floating marine structures we examined intra- and interspecific consumer interactions among biocontrol agents on different surface orientations. We tested the effect of identity, density and diversity of three invertebrates (the 11-arm seastar Coscinasterias muricata, the sea urchin Evechinus chloroticus and the gastropod Cook's turban Cookia sulcata) to reduce established biofouling and to prevent fouling growth on defouled surfaces. High densities of biocontrol agents were not more effective at fouling control (cover and biomass) than low densities. Nor did multi-species treatments function more effectively than mono-specific ones. However, biocontrol agent identity was important, with the 11-arm seastar and Cook's turban being the most effective at fouling reduction and prevention, respectively. Surface orientation had a strong effect on the effectiveness of control agents, with the best results obtained on vertical compared to diagonal and underside surfaces. This study confirmed the potential of biocontrol as a management tool for marine pest, indicating that identity is more important than richness and density of control agents. It also highlighted the limitations of this approach on diagonal and underside surfaces, where control agents have limited retention ability. PMID:26845376

  2. Maternal and perinatal aspects of birth defects: a case-control study

    PubMed Central

    Nhoncanse, Geiza Csar; Germano, Carla Maria R.; de Av, Lucimar Retto da S.; Melo, Dbora Gusmo

    2014-01-01

    Objective: To assess the prevalence of congenital defects and to investigate their maternal and perinatal associated aspects by reviewing Birth Certificates. Methods: Among all born alive infants from January 2003 to December 2007 in Maternidade da Santa Casa de Misericrdia of So Carlos, Southeast Brazil (12,199 infants), cases were identified as the newborns whose Birth Certificates registered any congenital defect. The same sex neonate born immediately after the case was chosen as a control. In total, 13 variables were analyzed: six were maternal related, three represented labor and delivery conditions and four were linked to fetal status. The chi-square and Fisher's exact tests were used to compare the variables, being significant p<0.05. Results: The prevalence of congenital defects was 0.38% and the association of two or more defects represented 32% of all cases. The number of mothers whose education level was equal or less than eight years was significantly higher among the group with birth defects (p=0.047). A higher frequency of prematurity (p<0.001) and cesarean delivery (p=0.004) was observed among children with birth defects. This group also showed lower birth weight and Apgar scores in the 1st and the 5th minute (p<0.001). Conclusions: The prevalence of congenital defect of 0.38% is possibly due to underreporting. The defects notified in the Birth Certificates were only the most visible ones, regardless of their severity. There is a need of adequate epidemiological monitoring of birth defects in order to create and expand prevention and treatment programs. PMID:24676186

  3. Electrical aspects of gaseous fuel flames for microgravity combustion and combustion control

    NASA Astrophysics Data System (ADS)

    Papac, Michael James

    This dissertation describes a fundamental study on the influence of electric fields on combustion reactions and their surrounding gases. A detailed literature survey is provided which outlines the works in the past that have contributed to the modern understanding of the fundamental processes. The interactions that occur when electric fields are applied to flames are complicated, and not enough information exists for electrode designs to be evaluated either by first principles or empirical correlations. Moreover, this prevents robust electric field actuators for control, a topic of great interest currently, from being developed without extensive testing. Electric field, chemical, and fluid-dynamic interactions that occur near the combustion reaction zone, and away from the reaction in the electrode spaces. Based on the results from the literature survey, an apparatus is constructed and a series of experiments are performed. A variety of diagnostics are used to probe flame shapes, sizes and the behaviors of the surrounding gases, as well as the characteristics of the electrical discharge from the flame. Techniques such as photography and schlieren imaging are employed for visualization, and chemiluminescence detection is used to probe the chemistry of the flame. In addition, ion probes are developed for measuring overall voltage-current characteristics and resolving the spatial distribution of ion current in the discharge. The system is analyzed analytically and a computational model is generated, providing a model of the system. The results of the model are used to elucidate the fundamental aspects of the system such as time constants, buoyancy characteristics, and chemical changes. Together, the combined experimental techniques and analysis provide a description of the fundamental processes that occur when electric fields are applied to flames beyond what is currently available and provides a method by which the design of such systems can be accomplished.

  4. Diversity of Stability, Localization, Interaction and Control of Downstream Gene Activity in the Maize Aux/IAA Protein Family

    PubMed Central

    Ludwig, Yvonne; Berendzen, Kenneth W.; Xu, Changzheng; Piepho, Hans-Peter; Hochholdinger, Frank

    2014-01-01

    AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) proteins are central regulators of auxin signal transduction. They control many aspects of plant development, share a conserved domain structure and are localized in the nucleus. In the present study, five maize Aux/IAA proteins (ZmIAA2, ZmIAA11, ZmIAA15, ZmIAA20 and ZmIAA33) representing the evolutionary, phylogenetic and expression diversity of this gene family were characterized. Subcellular localization studies revealed that ZmIAA2, ZmIAA11 and ZmIAA15 are confined to the nucleus while ZmIAA20 and ZmIAA33 are localized in both the nucleus and the cytoplasm. Introduction of specific point mutations in the degron sequence (VGWPPV) of domain II by substituting the first proline by serine or the second proline by leucine stabilized the Aux/IAA proteins. While protein half-life times between ?11 min (ZmIAA2) to ?120 min (ZmIAA15) were observed in wild-type proteins, the mutated forms of all five proteins were almost as stable as GFP control proteins. Moreover, all five maize Aux/IAA proteins repressed downstream gene expression in luciferase assays to different degrees. In addition, bimolecular fluorescence complementation (BiFC) analyses demonstrated interaction of all five Aux/IAA proteins with RUM1 (ROOTLESS WITH UNDETECTABLE MERISTEM 1, ZmIAA10) while only ZmIAA15 and ZmIAA33 interacted with the RUM1 paralog RUL1 (RUM-LIKE 1, ZmIAA29). Moreover, ZmIAA11, ZmIAA15 ZmIAA33 displayed homotypic interaction. Hence, despite their conserved domain structure, maize Aux/IAA proteins display a significant variability in their molecular characteristics which is likely associated with the wide spectrum of their developmental functions. PMID:25203637

  5. Aspects of black-fly control and entomology in the New World in relation to the Simulium problem in Nigeria*

    PubMed Central

    Crosskey, R. W.

    1959-01-01

    A general account is given of insecticidal control of black-flies in North and Central America, and the problems are contrasted with those arising in the control of Simulium damnosum Theo. in Nigeria. Some recent biological observations on Canadian black-flies are described, and it is emphasized that these have materially contributed to successful control. It is pointed out that S. damnosum control is being practised in the absence of much fundamental biological knowledge of this pest. Entomological aspects of onchocerciasis in Mexico and Guatemala are discussed, and compared with S. damnosum and its relationship to onchocerciasis in Nigeria. PMID:13813021

  6. Mitigating land loss in coastal Louisiana by controlled diversion of Mississippi River sand

    NASA Astrophysics Data System (ADS)

    Nittrouer, Jeffrey A.; Best, James L.; Brantley, Christopher; Cash, Ronald W.; Czapiga, Matthew; Kumar, Praveen; Parker, Gary

    2012-08-01

    After the 1927 flood of record on the Mississippi River, the Bonnet Carr Spillway in Louisiana was constructed as a flood control operation. When it is opened, the spillway diverts floodwaters from the Mississippi River to Lake Pontchartrain, to reduce the water discharge flowing past New Orleans. During the 2011 Mississippi River flood, which had the highest peak discharge since 1927, the Bonnet Carr Spillway was opened for 42 days, from 9May to 20 June. During this period, the average spillway discharge of 6,010m3s-1 amounted to 10-20% of the total river flood discharge. Here we present measurements of the areal extent and thickness of new sediments in the floodway, following the 2011 Mississippi flood. Only the upper 10-15% of the river water column was skimmed into the floodway. Yet, we conservatively estimate that 31-46% of the total sand load carried by the Mississippi River during the period of spillway opening was diverted. We find that local river conditions led to increased concentrations of suspended sand in the upper water column and thus led to diversion of sand from the river into the spillway. We conclude that an appropriate design of engineered river diversions in Louisiana can help mitigate coastal wetland loss.

  7. Yangtze River Water Diversion into Lake Taihu for Algal Bloom Control: Is it Helping or Hurting?

    NASA Astrophysics Data System (ADS)

    Acharya, K.; Li, Y.; Tang, C.; Qiu, L.; Yu, Z.

    2012-12-01

    Harmful algae blooms in Lake Taihu are getting worse every year due to excess nutrients flowing into the water, especially from the northern watershed areas. Impact of blooms on lake's ecosystem, fisheries and drinking water supply to local towns has been severe. Many efforts have been undertaken by both government entities and researchers since 1990 for restoring the lake such as dredging, wetland construction, control of watershed runoff but none has garnered more attention than the water-diversion project. In the water-diversion project, freshwater from the Yangtze River is transferred into the lake via the Wangyuhe River (in the north) and is eventually discharged from the lake via the Taipuhe River (in the south) in an attempt to dilute the polluted water and flush pollutants out of the lake. The effects of water transfer on lake water quality and ecology have drawn great attention because the effectiveness of this project is conflicting. Recent studies suggest that water transfer could only decrease the concentration of phytoplankton but may actually increase concentrations of phosphorus and nitrogen in some areas of the lake where nutrient concentrations are lower than the influent water. In this study, a three dimensional Environmental Fluid Dynamics Code (EFDC) model was used to investigate mass balance and spatial distribution of nutrients (mainly nitrogen and phosphorus) in Lake Taihu before and after transfer.

  8. Mineralogical Controls on Microbial Diversity in a Sulfuric Acid Karst System

    NASA Astrophysics Data System (ADS)

    Jones, A. A.; Bennett, P.

    2011-12-01

    The role mineralogy plays on microbial community distribution, composition, niche differentiation, and accumulation is a complex and nebulous association. Microbial phylogenetic diversity and bacterial composition of communities obtained from Lower Kane Cave (LKC), WY, USA, were studied using next generation bacterial 16S rRNA sequencing techniques. The microbial consortium found within LKC was found to be primarily composed of neutrophilic sulfur-oxidizing members of the gamma- and epsilon-proteobacteria . The microbial population within LKC has been instigated in previous studies to have a significant role in the processes of sulfuric acid speleogenesis. Using a LKC biomat as the inoculant in a series of 3 nutrient limited laboratory reactor experiments, and a pure culture of Thiothrix unzii (ATCC type strain 49747) in a parallel experiment, we found that both limestone and dolostone substratum consistently had higher biomass accumulation than silicate minerals in the same reactor. At the Class level, the carbonate substratum (Calcite, Limestone, and Dolostone) had ~84% - 88.7% of phylotypes in common. Aside from Basalt (Simpson's Index, D of 0.53), the carbonate substratum produced the least diverse phylotype distributions. Feldspar and quartz were colonized by the most diverse communities with Simpson's Index values of 0.16 and 0.31. Evaluation of metabolic guild distribution shows that potential neutrophilic sulfur-oxidizers have an affinity for acid neutralizing carbonate substrata over silicate substrata. These potential sulfur-oxidizing guilds compose ~28%-38% of the total microbial community. For feldspar and chert substratum, potential sulfur-oxidizing metabolic guilds composed merely ~5% of the total microbial community. The quartz substratum, in contrast, was uniquely populated by potential acidophilic sulfur-oxidizers Acidithiobacillus and Acidithiomicrobium; composing ~19% of the total community. A quartz substratum may offer these acidophiles a competitive advantage over other microbial communities that do not tolerate an acidic habitat, while optimizing the local microenvironment to better facilitate their metabolic pathway. The basalt substratum community was ~67% Thiothrix spp., a sulfur-oxidizing genus commonly associated with Deep-sea hydrothermal vents. This dominance of Thiothrix spp. on basalt may be due to an advantageous ability to extract, and take advantage of, mineral bound nutrients (P, Fe) in basalt. These results provide substantial evidence to support the hypothesis that mineralogy influences microbial distribution, composition, niche differentiation, and accumulation in a nutrient limited system. Specific microbial populations which have evolved to take advantage of specific mineral substrata and exert highly localized control of biogeochemical conditions. Mineralogy, therefore, plays an active part in the development of subsurface microbial ecology and diversity by exerting selective pressures on the subsurface microbial environment.

  9. Single-shot high aspect ratio bulk nanostructuring of fused silica using chirp-controlled ultrafast laser Bessel beams

    SciTech Connect

    Bhuyan, M. K.; Velpula, P. K.; Colombier, J. P.; Olivier, T.; Faure, N.; Stoian, R.

    2014-01-13

    We report single-shot, high aspect ratio nanovoid fabrication in bulk fused silica using zeroth order chirp-controlled ultrafast laser Bessel beams. We identify a unique laser pulse length and energy dependence of the physical characteristics of machined structures over which nanovoids of diameter in the range 200400?nm and aspect ratios exceeding 1000 can be fabricated. A mechanism based on the axial energy deposition of nonlinear ultrashort Bessel beams and subsequent material densification or rarefaction in fused silica is proposed, intricating the non-diffractive nature with the diffusing character of laser-generated free carriers. Fluid flow through nanochannel is also demonstrated.

  10. Targeting CTCF to Control Virus Gene Expression: A Common Theme amongst Diverse DNA Viruses

    PubMed Central

    Pentland, Ieisha; Parish, Joanna L.

    2015-01-01

    All viruses target host cell factors for successful life cycle completion. Transcriptional control of DNA viruses by host cell factors is important in the temporal and spatial regulation of virus gene expression. Many of these factors are recruited to enhance virus gene expression and thereby increase virus production, but host cell factors can also restrict virus gene expression and productivity of infection. CCCTC binding factor (CTCF) is a host cell DNA binding protein important for the regulation of genomic chromatin boundaries, transcriptional control and enhancer element usage. CTCF also functions in RNA polymerase II regulation and in doing so can influence co-transcriptional splicing events. Several DNA viruses, including Kaposis sarcoma-associated herpesvirus (KSHV), Epstein-Barr virus (EBV) and human papillomavirus (HPV) utilize CTCF to control virus gene expression and many studies have highlighted a role for CTCF in the persistence of these diverse oncogenic viruses. CTCF can both enhance and repress virus gene expression and in some cases CTCF increases the complexity of alternatively spliced transcripts. This review article will discuss the function of CTCF in the life cycle of DNA viruses in the context of known host cell CTCF functions. PMID:26154016

  11. The immersed boundary projection method and its application to simulation and control of flows around low-aspect-ratio wings

    NASA Astrophysics Data System (ADS)

    Taira, Kunihiko

    First, we present a new formulation of the immersed boundary method that is algebraically identical to the traditional fractional step algorithm. This method, called the immersed boundary projection method, allows for the simulations of incompressible flows over arbitrarily shaped bodies under motion and/or deformation in both two and three dimensions. The no-slip condition along the immersed boundary is enforced simultaneously with the incompressibility constraint through a single projection. The boundary force is determined implicitly without any constitutive relations for the rigid body formulation, which in turn allows the use of high CFL numbers in our simulations compared to past methods. Next, the above immersed boundary projection method is used to analyze three-dimensional separated flows around low-aspect-ratio flat-plate wings. A number of simulations highlighting the unsteady nature of the separated flows are performed for Re=300 and 500 with various aspect ratios, angles of attack, and planform geometries. The aspect ratio and angle of attack are found to have a large influence on the stability of the wake profile and the force experienced by the low-aspect-ratio wing. At early times, following an impulsive start, topologies of the wake vortices are found to be the same across different aspect ratios and angles of attack. Behind low-aspect-ratio rectangular plates, leading-edge vortices form and eventually separate as hairpin vortices following the start-up. This phenomenon is found to be similar to dynamic stall observed behind pitching plates. The detached structure would then interact with the tip vortices, reducing the downward velocity induced by the tip vortices acting upon the leading-edge vortex. At large time, depending on the aspect ratio and angles of attack, the wakes reach one of the three states: (i) a steady state, (ii) a periodic unsteady state, or (iii) an aperiodic unsteady state. We have observed that the tip effects in three-dimensional flows can stabilize the flow and also exhibit nonlinear interaction with the shedding vortices. At last, we apply steady blowing to separated flows behind the low-aspect-ratio rectangular wings. The objective of the flow control is to enhance lift at post-stall angles of attack by changing the dynamics of the wake vortices. This controller strengthens the tip vortices by engulfing the trailing-edge vortex sheet to increase the downward thrust and the downward induced velocity onto the leading-edge vortices. The tip vortices that are traditionally considered as an aerodynamic nuisance, have been used favorably to increase lift in post-stall flows for the considered low-aspect-ratio wings.

  12. PLANT SPECIES DIVERSITY IN NATIVE AND RESTORED TALLGRASS PRAIRIES: PATTERNS AND CONTROLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One goal of ecological restoration is to restore diversity of native vegetation, but mechanisms responsible for diversity in targeted communities often are poorly understood. We measured diversity (Simpson's index, 1/D) of plant species and functional groups of species in replicated 0.5-m2 plots wi...

  13. Proceedings of the Workshop on Computational Aspects in the Control of Flexible Systems, part 2

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence W., Jr. (Compiler)

    1989-01-01

    The Control/Structures Integration Program, a survey of available software for control of flexible structures, computational efficiency and capability, modeling and parameter estimation, and control synthesis and optimization software are discussed.

  14. Anaplasma marginale major surface protein 1a: a marker of strain diversity with implications for control of bovine anaplasmosis.

    PubMed

    Cabezas-Cruz, Alejandro; de la Fuente, Jos

    2015-04-01

    Classification of bacteria is challenging due to the lack of a theory-based framework. In addition, the adaptation of bacteria to ecological niches often results in selection of strains with diverse virulence, pathogenicity and transmission characteristics. Bacterial strain diversity presents challenges for taxonomic classification, which in turn impacts the ability to develop accurate diagnostics and effective vaccines. Over the past decade, the worldwide diversity of Anaplasma marginale, an economically important tick-borne pathogen of cattle, has become apparent. The extent of A. marginale strain diversity, formerly underappreciated, has contributed to the challenges of classification which, in turn, likely impacts the design and development of improved vaccines. Notably, the A. marginale surface protein 1a (MSP1a) is a model molecule for these studies because it serves as a marker for strain identity, is both an adhesin necessary for infection of cells and an immuno-reactive protein and is also an indicator of the evolution of strain diversity. Herein, we discuss a molecular taxonomic approach for classification of A. marginale strain diversity. Taxonomic analysis of this important molecule provides the opportunity to understand A. marginale strain diversity as it relates geographic and ecological factors and to the development of effective vaccines for control of bovine anaplasmosis worldwide. PMID:25802034

  15. Control aspects of the Schuchuli Village stand-alone photovoltaic power system

    NASA Technical Reports Server (NTRS)

    Groumpos, P. P.; Culler, J. E.; Delombard, R.

    1984-01-01

    A photovoltaic power system in an Arizona Indian village was installed. The control subsystem of this photovoltaic power system was analyzed. The four major functions of the control subsystem are: (1) voltage regulation; (2) load management; (3) water pump control; and (4) system protection. The control subsystem functions flowcharts for the control subsystem operation, and a computer program that models the control subsystem are presented.

  16. Some Aspects of Speech Production under Controlled Conditions of Oral Anaesthesia and Auditory Masking

    ERIC Educational Resources Information Center

    Hardcastle, W. J.

    1975-01-01

    Reports on the effects of oral anaesthesia and auditory masking on various aspects of speech articulation as objectively quantified by electropalatography and sound spectrography. The results show changes in speech production caused by altered tactile and auditory feedback. (Author/TL)

  17. Microbial Diversity in Sediments of Saline Qinghia Lake, China:Linking Geochemical Controls to Microbial Ecoloby

    SciTech Connect

    Dong, Hailiang; Zhang, Gengxin; Jiang, Hongchen; Yu, Bingsong; Chapman, Leah R.; Lucas, Courtney R.; Fields, Matthew W.

    2007-03-30

    Saline lakes at high altitudes represent an important andextreme microbial ecosystem, yet little is known about microbialdiversity in such environments. The objective of this study was toexamine the change of microbial diversity from the bottom of the lake tosediments of 40 cm in depth in a core from Qinghai Lake. The lake issaline (12.5 g/L salinity) and alkaline (pH 9.4) and is located on theQinghai-Tibetan Plateau at an altitude of 3196 m above sea level. Porewater chemistry of the core revealed low concentrations of sulfate andiron (<1 mM), but high concentrations of acetate (40-70 mM) anddissolved organic carbon (1596-5443 mg/L). Total organic carbon and totalnitrogen contents in the sediments were approximately 2 and<0.5percent, respectively. Acridine orange direct count data indicated thatcell numbers decreased from 4 x 10(9) cells/g at the water-sedimentinterface to 6 x 10(7) cells/g wet sediment at the 40-cm depth. Thischange in biomass was positively correlated with acetate concentration inpore water. Phospholipid fatty acid (PLFA) community structure analysesdetermined decrease in the proportion of the Proteobacteria and increasein the Firmicutes with increased depth. Characterization of small subunit(SSU) rRNA genes amplified from the sediments indicated a shift in thebacterial community with depth. Whereas the alpha-, beta-, andgamma-Proteobacteria and the Cytophaga/Flavobacterium/Bacteroides (CFB)were dominant at the water-sediment interface, low G + C gram-positivebacteria (a subgroup of Firmicutes) became the predominant group in theanoxic sediments. Both PLFA and the sequence data showed similar trend.The Proteobacteria, CFB, and gram-positive bacteria are present in othersaline lakes, but the presence of Actinobacteria andAcidobacteria/Holophaga in significant proportions in the Qinghai Lakesediments appears to be unique. The archaeal diversity was much lower,and clone sequences could be grouped in the Euryarchaeota andCrenarchaeota domains. The archaeal clones were not related to any knowncultures but to sequences previously found in methane-rich sediments.Acetate-utilizing methanogens were isolated from sediment incubations,and alpha- and gamma-proteobacterial isolates were obtained from a watersample from the lake-bottom (23 m). Our data collectively showed that theobserved diversity and shift in the community structure with depth wascorrelated with geochemical parameters (the redox state and availabilityof electron acceptor and donor). Heterotrophic methanogenesis is possiblyadominant metabolic process in the Qinghai Lake sediments. These resultsreinforce the importance of geochemical controls on microbial ecology insaline and alkaline lake environments.

  18. Genome-Wide Association Studies of HIV-1 Host Control in Ethnically Diverse Chinese Populations

    PubMed Central

    Wei, Zejun; Liu, Yang; Xu, Heng; Tang, Kun; Wu, Hao; Lu, Lin; Wang, Zhe; Chen, Zhengjie; Xu, Junjie; Zhu, Yufei; Hu, Landian; Shang, Hong; Zhao, Guoping; Kong, Xiangyin

    2015-01-01

    Genome-wide association studies (GWASs) have revealed several genetic loci associated with HIV-1 outcome following infection (e.g., HLA-C at 6p21.33) in multi-ethnic populations with genetic heterogeneity and racial/ethnic differences among Caucasians, African-Americans, and Hispanics. To systematically investigate the inherited predisposition to modulate HIV-1 infection in Chinese populations, we performed GWASs in three ethnically diverse HIV-infected patients groups (i.e., HAN, YUN, and XIN, N?=?538). The reported loci at 6p21.33 was validated in HAN (e.g., rs9264942, P?=?0.0018). An independent association signal (rs2442719, P?=?7.85??10?7, HAN group) in the same region was observed. Imputation results suggest that haplotype HLA-B*13:02/C*06:02, which can partially account for the GWAS signal, is associated with lower viral load in Han Chinese. Moreover, several novel loci were identified using GWAS approach including the top association signals at 6q13 (KCNQ5, rs947612, P?=?2.15??10?6), 6p24.1 (PHACTR1, rs202072, P?=?3.8??10?6), and 11q12.3 (SCGB1D4, rs11231017, P?=?7.39??10?7) in HAN, YUN, and XIN groups, respectively. Our findings imply shared or specific mechanisms for host control of HIV-1 in ethnically diverse Chinese populations, which may shed new light on individualized HIV/AIDS therapy in China. PMID:26039976

  19. Bacterial Community Structure of Acid-Impacted Lakes: What Controls Diversity??

    PubMed Central

    Percent, Sascha F.; Frischer, Marc E.; Vescio, Paul A.; Duffy, Ellen B.; Milano, Vincenzo; McLellan, Maggie; Stevens, Brett M.; Boylen, Charles W.; Nierzwicki-Bauer, Sandra A.

    2008-01-01

    Although it is recognized that acidification of freshwater systems results in decreased overall species richness of plants and animals, little is known about the response of aquatic microbial communities to acidification. In this study we examined bacterioplankton community diversity and structure in 18 lakes located in the Adirondack Park (in the state of New York in the United States) that were affected to various degrees by acidic deposition and assessed correlations with 31 physical and chemical parameters. The pH of these lakes ranged from 4.9 to 7.8. These studies were conducted as a component of the Adirondack Effects Assessment Program supported by the U.S. Environmental Protection Agency. Thirty-one independent 16S rRNA gene libraries consisting of 2,135 clones were constructed from epilimnion and hypolimnion water samples. Bacterioplankton community composition was determined by sequencing and amplified ribosomal DNA restriction analysis of the clone libraries. Nineteen bacterial classes representing 95 subclasses were observed, but clone libraries were dominated by representatives of the Actinobacteria and Betaproteobacteria classes. Although the diversity and richness of bacterioplankton communities were positively correlated with pH, the overall community composition assessed by principal component analysis was not. The strongest correlations were observed between bacterioplankton communities and lake depth, hydraulic retention time, dissolved inorganic carbon, and nonlabile monomeric aluminum concentrations. While there was not an overall correlation between bacterioplankton community structure and pH, several bacterial classes, including the Alphaproteobacteria, were directly correlated with acidity. These results indicate that unlike more identifiable correlations between acidity and species richness for higher trophic levels, controls on bacterioplankton community structure are likely more complex, involving both direct and indirect processes. PMID:18245245

  20. Improving Area Control Error Diversity Interchange (ADI) Program by Incorporating Congestion Constraints

    SciTech Connect

    Zhou, Ning; Etingov, Pavel V.; Makarov, Yuri V.; Guttromson, Ross T.; McManus, Bart

    2010-04-30

    The area control error (ACE) determines how much a balancing authority (BA) needs to move its regulating units to meet mandatory control performance standard requirements. Regulation is an expensive resource that could cost several hundred million dollars a year for a BA. The amount of regulation needed in a system is increasing with more intermittent generation resources added to the system. The ACE diversity interchange (ADI) program provides a tool for reducing the regulation requirement by combining ACEs from several participating BAs followed by sharing the total ACE among all participating balancing areas. The effect is achieved as a result of the low statistical correlation between the original ACEs of participating BAs. A rule-based ADI approach has already been put into practice in the US Western Interconnection. The degree of actual ACE sharing is artificially limited because of the unknown redistribution of power flows and possible system congestion (these factors are not monitored in the existing ADI). This paper proposes a two-step linear programming (LP) ADI approach that incorporates congestion constraints. In the first step of the proposed LP ADI, the line transmission limits are enforced by setting up corresponding constraints. In the second step, the business fairness is pursued. Simulation is performed to compare the properties of the proposed LP ADI and the existing rule-based ADI. Favorable features, such as avoiding line limit violations and increasing the degree of possible ACE sharing, are observed for the proposed LP ADI.

  1. Increasing zooplankton size diversity enhances the strength of top-down control on phytoplankton in the East China Sea

    NASA Astrophysics Data System (ADS)

    Ye, L.; Chang, C.; Garca-Comas, C.; Gong, G.; Hsieh, C.

    2012-12-01

    Body size is one of the fundamental characteristics of organisms linking many ecosystem properties and functions. Recent studies suggest that environmental changes alter the size structure of pelagic food webs; however, ecosystem consequences of such changes remain unclear. Here we tested our main hypothesis that increasing zooplankton size diversity enhances top-down control on phytoplankton in the East China Sea (H1), as well as five conventional hypotheses explaining the top-down control: shallower zooplankton size spectrum enhances the strength of top-down control (H2); nutrient enrichment lessens the strength of top-down control (H3); increasing zooplankton taxonomic diversity enhances the strength of top-down control (H4); increasing fish predation is linked to decreasing the strength of top-down control of zooplankton on phytoplankton (H5); increasing temperature intensifies the strength of top-down control (H6). While the results of our univariate analyses support H1, H2, H3, and H4, more in depth analyses indicate that zooplankton size diversity is the most important factor in determining the strength of top-down control on phytoplankton in East China Sea. Our results suggest a new potential mechanism that increasing predator size diversity enhances the strength of top-down control on prey through diet niche partitioning. This mechanism can be explained by the concept of optimal predator-prey body-mass ratio concept. Suppose each size group of zooplankton predators has its own optimal phytoplankton prey size, increasing size diversity of zooplankton would promote diet niche partitioning of predators and thus elevates the top-down control.Fig. 1 Scatter plots the relationship between zooplankton/phytoplankton biomass ratio versus (A) zooplankton size diversity, (B) slope of zooplankton size spectrum, (C) Zoolankton Shannon diversity, (D) NO3, (E) PO4, (F) SiO3, (G) water temperature, and (H) fish larvae density in the East China Sea. Table 1. Results of the generalized linear mixed-effect model in investigating the effect of each factor on the spatiotemporal dynamics of zooplankton/phytoplankton biomass ratio in the East China Sea, with sampling cruises as a random effect. A lower value of AIC represents better goodness of fit of the model. The p-value was estimated based on MCMC sampling.

  2. Mechanisms Controlling Carbon Turnover from Diverse Microbial Groups in Temperate and Tropical Forest Soils

    NASA Astrophysics Data System (ADS)

    Throckmorton, H.; Dane, L.; Bird, J. A.; Firestone, M. K.; Horwath, W. R.

    2010-12-01

    Microorganisms represent an important intermediate along the pathway of plant litter decomposition to the formation of soil organic matter (SOM); yet little is known of the fate and stability of microbial C in soils and the importance of microbial biochemistry as a factor influencing SOM dynamics. This research investigates mechanisms controlling microbial C stabilization in a temperate forest in the Sierra Nevada of California (CA) and a tropical forest in Puerto Rico (PR). Biochemically diverse microbial groups (fungi, actinomycetes, bacteria gram (+), and bacteria gram (-)) were isolated from both sites, grown in the laboratory with C13 media, killed, and nonliving residues were added back to soils as a reciprocal transplant of microbial groups. The native microbial community in CA is dominated by fungi and in PR is dominated by bacteria, which provides an opportunity to asses the metabolic response of distinct microbial communities to the diverse microbial additions. CA and PR soils were sampled five times over a 3 and 2 year period, respectively. In CA there was no significant difference in the mean residence time (MRT) of diverse C13 microbial treatments; whereas in PR there were significant differences, whereby temperate fungi, temperate Gram (+) bacteria, and tropical actinomycetes exhibited a significantly longer MRT as compared with tropical fungi and temperate Gram (-). These results suggest that a bacterial dominated microbial community discriminates more amongst diverse substrates than a fungal-dominated community. MRT for labeled-C in CA was 5.21 1.11 years, and in PR was 2.22 0.45. Despite substantial differences in MRT between sites, physical fractionation of soils into light (LF), aggregated-occluded (OF), and mineral-associated (MF) fractions provided evidence that accelerated decomposition in PR (presumably due to climate) operated primarily on labeled-C unassociated with the mineral matrix (LF); labeled-C occluded within aggregates (OF) or bound to the mineral matrix (MF) exhibited similar turnover dynamics for the two sites. Py-GC-MS-IRMS examined the fate of labeled temperate fungal residues at the molecular level in CA (30 days) and in PR (17 days) in whole soils and soil fractions. Results showed notably high enrichment of two polysaccharide biomarkers at both sites (2-furancarboxaldehyde, 5-methyl; and levoglucosanone); as well as an enol compound. These compounds did not occur in high abundance in the original fungal residues, suggesting selective preservation or secondary formation of these compounds in both CA and PR soils. Two additional lipid biomarkers exhibited notably high enrichment in CA but not PR soils, suggesting some distinct pathways of humification may be occurring at each site. Physical fractionation combined with molecular analysis suggests that protection by aggregate-occlusion (OF) and chemical complexation with soil mineral surfaces (MF) represent distinct protection mechanisms that operate on different microbial compounds.

  3. Microbial diversity in sediments of saline Qinghai Lake, China: linking geochemical controls to microbial ecology.

    PubMed

    Dong, Hailiang; Zhang, Gengxin; Jiang, Hongchen; Yu, Bingsong; Chapman, Leah R; Lucas, Courtney R; Fields, Matthew W

    2006-01-01

    Saline lakes at high altitudes represent an important and extreme microbial ecosystem, yet little is known about microbial diversity in such environments. The objective of this study was to examine the change of microbial diversity from the bottom of the lake to sediments of 40 cm in depth in a core from Qinghai Lake. The lake is saline (12.5 g/L salinity) and alkaline (pH 9.4) and is located on the Qinghai-Tibetan Plateau at an altitude of 3196 m above sea level. Pore water chemistry of the core revealed low concentrations of sulfate and iron (<1 mM), but high concentrations of acetate (40-70 mM) and dissolved organic carbon (1596-5443 mg/L). Total organic carbon and total nitrogen contents in the sediments were approximately 2 and <0.5%, respectively. Acridine orange direct count data indicated that cell numbers decreased from 4 x 10(9) cells/g at the water-sediment interface to 6 x 10(7) cells/g wet sediment at the 40-cm depth. This change in biomass was positively correlated with acetate concentration in pore water. Phospholipid fatty acid (PLFA) community structure analyses determined decrease in the proportion of the Proteobacteria and increase in the Firmicutes with increased depth. Characterization of small subunit (SSU) rRNA genes amplified from the sediments indicated a shift in the bacterial community with depth. Whereas the alpha-, beta-, and gamma-Proteobacteria and the Cytophaga/Flavobacterium/Bacteroides (CFB) were dominant at the water-sediment interface, low G + C gram-positive bacteria (a subgroup of Firmicutes) became the predominant group in the anoxic sediments. Both PLFA and the sequence data showed similar trend. The Proteobacteria, CFB, and gram-positive bacteria are present in other saline lakes, but the presence of Actinobacteria and Acidobacteria/Holophaga in significant proportions in the Qinghai Lake sediments appears to be unique. The archaeal diversity was much lower, and clone sequences could be grouped in the Euryarchaeota and Crenarchaeota domains. The archaeal clones were not related to any known cultures but to sequences previously found in methane-rich sediments. Acetate-utilizing methanogens were isolated from sediment incubations, and alpha- and gamma-proteobacterial isolates were obtained from a water sample from the lake-bottom (23 m). Our data collectively showed that the observed diversity and shift in the community structure with depth was correlated with geochemical parameters (the redox state and availability of electron acceptor and donor). Heterotrophic methanogenesis is possibly adominant metabolic process in the Qinghai Lake sediments. These results reinforce the importance of geochemical controls on microbial ecology in saline and alkaline lake environments. PMID:16400537

  4. Hydrographic controls on marine organic matter fate and microbial diversity in the western Irish Sea

    NASA Astrophysics Data System (ADS)

    O'Reilly, Shane; Szpak, Michal; Monteys, Xavier; Flanagan, Paul; Allen, Christopher; Kelleher, Brian

    2014-05-01

    Cycling of organic matter (OM) is the key biological process in the marine environment1 and knowledge of the sources and the reactivity of OM, in addition to factors controlling its distribution in estuarine, coastal and shelf sediments are of key importance for understanding global biogeochemical cycles2. With recent advances in cultivation-independent molecular approaches to microbial ecology, the key role of prokaryotes in global biogeochemical cycling in marine ecosystems has been emphasised3,4. However, spatial studies combining the distribution and fate of OM with microbial community abundance and diversity remain rare. Here, a combined spatial lipid biomarker and 16S rRNA tagged pyrosequencing study was conducted in surface sediments and particulate matter across hydrographically distinct zones associated with the seasonal western Irish Sea gyre. The aim was to assess the spatial variation of, and factors controlling, marine organic cycling and sedimentary microbial communities across these distinct zones. The distribution of phospholipid fatty acids, source-specific sterols, wax esters and C25 highly branched isoprenoids indicate that diatoms, dinoflagellates and green algae were the major contributors of marine organic matter, while the distribution of cholesterol, wax esters and C20 and C22 polyunsaturated fatty acids have highlighted the importance of copepod grazing for mineralizing organic matter in the water column5. This marine OM production and mineralisation was greatest in well-mixed waters compared to offshore stratified waters. Lipid analysis and 16S rRNA PCR-DGGE profiling also suggests that sedimentary bacterial abundance increases while community diversity decreases in offshore stratified waters. The major bacterial classes are the Deltaproteobacteria, Clostridia, Flavobacteriia, Gammaproteobactera and Bacteroiidia. At the family/genus level most groups appear to be associated with organoheterotrophic processing of sedimentary OM, ranging from degradation of complex organic matter (e.g. Tepidibacter sp.) to sulfur-dependent utilisation of simple organic molecules (e.g. Desulfobulbaceae and Desulfuromonadaceae. 1. Hedges and Keil (1995) Mar Chem 49, 81-115. 2. Baldock et al., (2004) Mar Chem 92, 39-64. 3. Deming and Baross, (1993) Plenum Press, NY. 4. 4. Gooday, (2002) J Oceanogr 58, 305-332. 5. O'Reilly et al., (2013) Estuar, Coast & Shelf Sci. http://dx.doi.org/10.1016/j.ecss.2013.11.002

  5. Subsonic and transonic pressure measurements on a high-aspect-ratio supercritical-wing model with oscillating control surfaces

    NASA Technical Reports Server (NTRS)

    Sandford, M. C.; Ricketts, R. H.; Watson, J. J.

    1981-01-01

    A high aspect ratio supercritical wing with oscillating control surfaces is described. The semispan wing model was instrumented with 252 static orifices and 164 in situ dynamic pressure gases for studying the effects of control surface position and sinusoidal motion on steady and unsteady pressures. Data from the present test (this is the second in a series of tests on this model) were obtained in the Langley Transonic Dynamics Tunnel at Mach numbers of 0.60 and 0.78 and are presented in tabular form.

  6. Control of the visual and tactile aspects of poultry food according to the poultry food behavior by image analysis

    NASA Astrophysics Data System (ADS)

    Hachemi, R.; Vincent, N.; Lomenie, N.

    2007-01-01

    This study tries to connect the poultry food behavior to the visual and tactile characteristics of the food. The aim of the work is to make it possible to control the visual and tactile aspects of food (food pellets), by means of image analysis. These aspects are often suspected to explain the undesirable behavior of the poultries, which can reject a food, showing however optimal nutritional characteristics. These incidents involve important negative consequences as well for the animal as for the poultry breeder, with a major degradation of the technical and economic performances. Many zootechnical studies and observations in breeding testify to the sensitivity of the poultries to the visual and tactile aspects of food, but measurements classically used to characterize them do not allow explaining this phenomenon. Color, texture and shape features extracted from images of pellets will constitute effective and practical measures to describe their visual and tactile aspects. We show that a pellets classification based on visual features and supervised by a set of poultry food behavior labels allows to select a set of discriminating features.

  7. Proceedings of the Workshop on Computational Aspects in the Control of Flexible Systems, part 1

    NASA Technical Reports Server (NTRS)

    Taylor, Lawrence W., Jr. (Compiler)

    1989-01-01

    Control/Structures Integration program software needs, computer aided control engineering for flexible spacecraft, computer aided design, computational efficiency and capability, modeling and parameter estimation, and control synthesis and optimization software for flexible structures and robots are among the topics discussed.

  8. Transcription control pathways decode patterned synaptic inputs into diverse mRNA expression profiles.

    PubMed

    Jain, Pragati; Bhalla, Upinder S

    2014-01-01

    Synaptic plasticity requires transcription and translation to establish long-term changes that form the basis for long term memory. Diverse stimuli, such as synaptic activity and growth factors, trigger synthesis of mRNA to regulate changes at the synapse. The palette of possible mRNAs is vast, and a key question is how the cell selects which mRNAs to synthesize. To address this molecular decision-making, we have developed a biochemically detailed model of synaptic-activity triggered mRNA synthesis. We find that there are distinct time-courses and amplitudes of different branches of the mRNA regulatory signaling pathways, which carry out pattern-selective combinatorial decoding of stimulus patterns into distinct mRNA subtypes. Distinct, simultaneously arriving input patterns that impinge on the transcriptional control network interact nonlinearly to generate novel mRNA combinations. Our model combines major regulatory pathways and their interactions connecting synaptic input to mRNA synthesis. We parameterized and validated the model by incorporating data from multiple published experiments. The model replicates outcomes of knockout experiments. We suggest that the pattern-selectivity mechanisms analyzed in this model may act in many cell types to confer the capability to decode temporal patterns into combinatorial mRNA expression. PMID:24787753

  9. Stimulo-deterrent diversion: A concept and its possible application to onion maggot control.

    PubMed

    Miller, J R; Cowles, R S

    1990-11-01

    Considerable basic information has been gathered on the interaction between the onion fly (Delia antiqua) and its host plant, the onion (Allium cepa). An attempt is underway to manipulate ovipositional behavior of this pest by treating onion seedlings with chemical deterrents while simultaneously providing deeply planted onion culls on which onion flies prefer to lay. This bipolar strategy of behavioral manipulation, termed "stimulo-deterrent diversion" (SDD), has the advantages of: (1) avoiding severe pest deprival and concomitant overriding of deterrents, (2) combining the effects of "push" and "pull" multiplicatively, and (3) providing opportunities for enhanced biological control in sites where the pest becomes concentrated. The suggestion is made that using SDD along with soil insecticide might relax or even reverse selection for physiological resistance ofD. antiqua to insecticides. As tools of molecular biology open new possibilities for manipulating plants and their allelochemicals, applied chemical ecologists should consider arranging situations where the allelochemicals have clear and adaptive messages for the pest. By combining toxins and deterrents at sites where feeding should be prevented, while simultaneously expediting use of alternative plants or plant parts, it might be possible to guide pest evolution toward paths of less conflict with human interest. PMID:24263303

  10. Relationship between bacterial diversity and function under biotic control: the soil pesticide degraders as a case study.

    PubMed

    Monard, Ccile; Vandenkoornhuyse, Philippe; Le Bot, Barbara; Binet, Franoise

    2011-06-01

    In soil, the way biotic parameters impact the relationship between bacterial diversity and function is still unknown. To understand these interactions better, we used RNA-based stable-isotope probing to study the diversity of active atrazine-degrading bacteria in relation to atrazine degradation and to explore the impact of earthworm-soil engineering with respect to this relationship. Bulk soil, burrow linings and earthworm casts were incubated with (13)C-atrazine. The pollutant degradation was quantified by liquid chromatography-mass spectrometry for 8 days, whereas active atrazine degraders were identified at 2 and 8 days by sequencing the 16S ribosomal RNA in the (13)C-RNA fractions from the three soil microsites. An original diversity of atrazine degraders was found. Earthworm soil engineering greatly modified the taxonomic composition of atrazine degraders with dominance of ?-, ?- and ?-proteobacteria in burrow linings and of Actinobacteria in casts. Earthworm soil bioturbation increased the ?-diversity of atrazine degraders over the soil microsites generated. Atrazine degradation was enhanced in burrow linings in which primary atrazine degraders, closely related to Pelomonas aquatica, were detected only 2 days after atrazine addition. Atrazine degradation efficiency was not linearly related to the species richness of degraders but likely relied on keystone species. By enhancing soil heterogeneity, earthworms sustained high phylogenetic bacterial diversity and exerted a biotic control on the bacterial diversity-function relationships. Our findings call for future investigations to assess the ecological significance of biotic controls on the relationships between diversity and function on ecosystem properties and services (for example, soil detoxification) at larger scales. PMID:21160539

  11. Landscape Diversity and Crop Vigor Influence Biological Control of the Western Grape Leafhopper (E. elegantula Osborn) in Vineyards

    PubMed Central

    Wilson, Houston; Miles, Albie F.; Daane, Kent M.; Altieri, Miguel A.

    2015-01-01

    This study evaluated how the proportional area of natural habitat surrounding a vineyard (i.e. landscape diversity) worked in conjunction with crop vigor, cultivar and rootstock selection to influence biological control of the western grape leafhopper (Erythroneura elegantula Osborn). The key natural enemies of E. elegantula are Anagrus erythroneurae S. Trjapitzin & Chiappini and A. daanei Triapitsyn, both of which are likely impacted by changes in landscape diversity due to their reliance on non-crop habitat to successfully overwinter. Additionally, E. elegantula is sensitive to changes in host plant quality which may influence densities on specific cultivars, rootstocks and/or vines with increased vigor. From 2010–2013, data were collected on natural enemy and leafhopper densities, pest parasitism rates and vine vigor from multiple vineyards that represented a continuum of landscape diversity. Early in the season, vineyards in more diverse landscapes had higher Anagrus spp. densities and lower E. elegantula densities, which led to increased parasitism of E. elegantula. Although late season densities of E. elegantula tended to be lower in vineyards with higher early season parasitism rates and lower total petiole nitrogen content, they were also affected by rootstock and cultivar. While diverse landscapes can support higher natural enemy populations, which can lead to increased biological control, leafhopper densities also appear to be mediated by cultivar, rootstock and vine vigor. PMID:26555074

  12. A Conserved Supergene Locus Controls Colour Pattern Diversity in Heliconius Butterflies

    PubMed Central

    Joron, Mathieu; Papa, Riccardo; Beltrn, Margarita; Chamberlain, Nicola; Mavrez, Jess; Baxter, Simon; Abanto, Moiss; Bermingham, Eldredge; Humphray, Sean J; Rogers, Jane; Beasley, Helen; Barlow, Karen; H. ffrench-Constant, Richard; Mallet, James; McMillan, W. Owen; Jiggins, Chris D

    2006-01-01

    We studied whether similar developmental genetic mechanisms are involved in both convergent and divergent evolution. Mimetic insects are known for their diversity of patterns as well as their remarkable evolutionary convergence, and they have played an important role in controversies over the respective roles of selection and constraints in adaptive evolution. Here we contrast three butterfly species, all classic examples of Mllerian mimicry. We used a genetic linkage map to show that a locus, Yb, which controls the presence of a yellow band in geographic races of Heliconius melpomene, maps precisely to the same location as the locus Cr, which has very similar phenotypic effects in its co-mimic H. erato. Furthermore, the same genomic location acts as a supergene, determining multiple sympatric morphs in a third species, H. numata. H. numata is a species with a very different phenotypic appearance, whose many forms mimic different unrelated ithomiine butterflies in the genus Melinaea. Other unlinked colour pattern loci map to a homologous linkage group in the co-mimics H. melpomene and H. erato, but they are not involved in mimetic polymorphism in H. numata. Hence, a single region from the multilocus colour pattern architecture of H. melpomene and H. erato appears to have gained control of the entire wing-pattern variability in H. numata, presumably as a result of selection for mimetic supergene polymorphism without intermediates. Although we cannot at this stage confirm the homology of the loci segregating in the three species, our results imply that a conserved yet relatively unconstrained mechanism underlying pattern switching can affect mimicry in radically different ways. We also show that adaptive evolution, both convergent and diversifying, can occur by the repeated involvement of the same genomic regions. PMID:17002517

  13. Landscape-level controls on dissolved carbon flux from diverse catchments of the circumboreal

    NASA Astrophysics Data System (ADS)

    Tank, Suzanne E.; Frey, Karen E.; Striegl, Robert G.; Raymond, Peter A.; Holmes, Robert M.; McClelland, James W.; Peterson, Bruce J.

    2012-09-01

    While much of the dissolved organic carbon (DOC) within rivers is destined for mineralization to CO2, a substantial fraction of riverine bicarbonate (HCO3-) flux represents a CO2 sink, as a result of weathering processes that sequester CO2 as HCO3-. We explored landscape-level controls on DOC and HCO3- flux in subcatchments of the boreal, with a specific focus on the effect of permafrost on riverine dissolved C flux. To do this, we undertook a multivariate analysis that partitioned the variance attributable to known, key regulators of dissolved C flux (runoff, lithology, and vegetation) prior to examining the effect of permafrost, using riverine biogeochemistry data from a suite of subcatchments drawn from the Mackenzie, Yukon, East, and West Siberian regions of the circumboreal. Across the diverse catchments that we study, controls on HCO3-flux were near-universal: runoff and an increased carbonate rock contribution to weathering (assessed as riverwater Ca:Na) increased HCO3- yields, while increasing permafrost extent was associated with decreases in HCO3-. In contrast, permafrost had contrasting and region-specific effects on DOC yield, even after the variation caused by other key drivers of its flux had been accounted for. We used ionic ratios and SO4 yields to calculate the potential range of CO2sequestered via weathering across these boreal subcatchments, and show that decreasing permafrost extent is associated with increases in weathering-mediated CO2 fixation across broad spatial scales, an effect that could counterbalance some of the organic C mineralization that is predicted with declining permafrost.

  14. Landscape-level controls on dissolved carbon flux from diverse catchments of the circumboreal

    USGS Publications Warehouse

    Tank, Suzanne; Frey, Karen E.; Striegl, Robert G.; Raymond, Peter A.; Holmes, R. Max; McClelland, James W.; Peterson, Bruce J.

    2012-01-01

    While much of the dissolved organic carbon (DOC) within rivers is destined for mineralization to CO2, a substantial fraction of riverine bicarbonate (HCO3-) flux represents a CO2 sink, as a result of weathering processes that sequester CO2 as HCO3-. We explored landscape-level controls on DOC and HCO3- flux in subcatchments of the boreal, with a specific focus on the effect of permafrost on riverine dissolved C flux. To do this, we undertook a multivariate analysis that partitioned the variance attributable to known, key regulators of dissolved C flux (runoff, lithology, and vegetation) prior to examining the effect of permafrost, using riverine biogeochemistry data from a suite of subcatchments drawn from the Mackenzie, Yukon, East, and West Siberian regions of the circumboreal. Across the diverse catchments that we study, controls on HCO3- flux were near-universal: runoff and an increased carbonate rock contribution to weathering (assessed as riverwater Ca:Na) increased HCO3- yields, while increasing permafrost extent was associated with decreases in HCO3-. In contrast, permafrost had contrasting and region-specific effects on DOC yield, even after the variation caused by other key drivers of its flux had been accounted for. We used ionic ratios and SO4 yields to calculate the potential range of CO2 sequestered via weathering across these boreal subcatchments, and show that decreasing permafrost extent is associated with increases in weathering-mediated CO2 fixation across broad spatial scales, an effect that could counterbalance some of the organic C mineralization that is predicted with declining permafrost.

  15. Nanometer scale high-aspect-ratio trench etching at controllable angles using ballistic reactive ion etching

    SciTech Connect

    Cybart, Shane; Roediger, Peter; Ulin-Avila, Erick; Wu, Stephen; Wong, Travis; Dynes, Robert

    2012-11-30

    We demonstrate a low pressure reactive ion etching process capable of patterning nanometer scale angled sidewalls and three dimensional structures in photoresist. At low pressure the plasma has a large dark space region where the etchant ions have very large highly-directional mean free paths. Mounting the sample entirely within this dark space allows for etching at angles relative to the cathode with minimal undercutting, resulting in high-aspect ratio nanometer scale angled features. By reversing the initial angle and performing a second etch we create three-dimensional mask profiles.

  16. Materials for Pharmaceutical Dosage Forms: Molecular Pharmaceutics and Controlled Release Drug Delivery Aspects

    PubMed Central

    Mansour, Heidi M.; Sohn, MinJi; Al-Ghananeem, Abeer; DeLuca, Patrick P.

    2010-01-01

    Controlled release delivery is available for many routes of administration and offers many advantages (as microparticles and nanoparticles) over immediate release delivery. These advantages include reduced dosing frequency, better therapeutic control, fewer side effects, and, consequently, these dosage forms are well accepted by patients. Advances in polymer material science, particle engineering design, manufacture, and nanotechnology have led the way to the introduction of several marketed controlled release products and several more are in pre-clinical and clinical development. PMID:20957095

  17. [Epidemics of Ebola haemorrhagic fever in Gabon (1994-2002). Epidemiologic aspects and considerations on control measures].

    PubMed

    Milleliri, J M; Tévi-Benissan, C; Baize, S; Leroy, E; Georges-Courbot, M C

    2004-08-01

    Based on the description of the four Ebola haemorrhagic fever epidemics (EHF) occurred in Gabon between 1994 and 2002, the authors are considering the cultural and psycho-sociological aspects accounting for the difficulty to implement control measures. On the whole, the result of these raging epidemics came up to 207 cases and 150 dead (lethality: 72%). Analysing precisely the aspects of the third epidemic and pointing up the possible factors explaining its spreading far beyond its epicentre, the authors bring about the limits of measures not always understood by local populations. The discussion will deal with the possibilities of a better surveillance, a quick management of intervention means including a regional permanent pre-alert and taking into account the issue raised by the possible Ebola virus endemic. PMID:15462203

  18. Braiding of submarine channels controlled by aspect ratio similar to rivers

    NASA Astrophysics Data System (ADS)

    Foreman, Brady Z.; Lai, Steven Y. J.; Komatsu, Yuhei; Paola, Chris

    2015-09-01

    The great majority of submarine channels formed by turbidity and density currents are meandering in planform; they consist of a single, sinuous channel that transports a turbid, dense flow of sediment from submarine canyons to ocean floor environments. Braided turbidite systems consisting of multiple, interconnected channel threads are conspicuously rare. Furthermore, such systems may not represent the spontaneous planform instability of true braiding, but instead result from erosive processes or bathymetric variability. In marked contrast to submarine environments, both meandering and braided planforms are common in fluvial systems. Here we present experiments of subaqueous channel formation conducted at two laboratory facilities. We find that density currents readily produce a braided planform for flow aspect ratios of depth to width that are similar to those that produce river braiding. Moreover, we find that stability model theory for river planform morphology successfully describes submarine channels in both experiments and the field. On the basis of these observations, we propose that the rarity of braided submarine channels is explained by the generally greater flow depths in submarine systems, which necessitate commensurately greater widths to achieve the required aspect ratio, along with feedbacks among flow thickness, suspended sediment concentration and channel relief that induce greater levee deposition rates and limit channel widening.

  19. Which Aspects of Postural Control Differentiate between Patients with Parkinson's Disease with and without Freezing of Gait?

    PubMed

    Vervoort, Griet; Nackaerts, Evelien; Mohammadi, Farshid; Heremans, Elke; Verschueren, Sabine; Nieuwboer, Alice; Vercruysse, Sarah

    2013-01-01

    This exploratory study aimed to identify which aspects of postural control are able to distinguish between subgroups of patients with Parkinson's disease (PD) and controls. Balance was tested using static and dynamic posturography. Freezers (n = 9), nonfreezers (n = 10), and controls (n = 10) stood on a movable force platform and performed 3 randomly assigned tests: (1) sensory organization test (SOT) to evaluate the effective use of sensory information, (2) motor control test (MCT) to assess automatic postural reactions in response to platform perturbations, and (3) rhythmic weight shift test (RWS) to evaluate the ability to voluntarily move the center of gravity (COG) mediolaterally and anterior-posteriorly (AP). The respective outcome measures were equilibrium and postural strategy scores, response strength and amplitude of weight shift. Patients were in the "on" phase of the medication cycle. In general, freezers performed similarly on SOT and MCT compared to nonfreezers. Freezers showed an intact postural strategy during sensory manipulations and an appropriate response to external perturbations. However, during voluntary weight shifting, freezers showed poorer directional control compared to nonfreezers and controls. This suggests that freezers have adequate automatic postural control and sensory integration abilities in quiet stance, but show specific directional control deficits when weight shifting is voluntary. PMID:23936729

  20. [Genetic diversity of wild reindeer (Rangifer tarandus) of Taimyr: analysis of polymorphism of the control region of mitochondrial DNA].

    PubMed

    Kholodova, M V; Kolpashchikov, L A; Kuznetsova, M V; Baranova, A I

    2011-01-01

    Based on an analysis of the polymorphism of nucleotide sequences (n = 111) of the control region (left domain) of mtDNA, the genetic diversity of the largest population of wild reindeer Rangifer tarandus in Eurasia, which inhabits Taimyr peninsula, was studied. High levels of gaplotypic (H) and nucleotide (pi) diversity (0.987 and 0.018, respectively) were revealed, which indicate the long existence of this population and the sufficiently stable growth of the population. The absence of long periods of abrupt decrease in the number of the Taimyr population of wild reindeer and/or facts of formation of its genetic diversity as a result of mixing of genetically distant conspecific populations is supported by the data on the distribution pattern of frequencies of pair differences between nucleotide sequences and the topology of the phylogenetic tree. The low level of genetic differences between reindeer from the western, central, and eastern groups reflects their common origin and close kinship. PMID:21442907

  1. Some stability and control aspects of airframe/propulsion system interactions on the YF-12 airplane

    NASA Technical Reports Server (NTRS)

    Berry, D. T.; Gilyard, G. B.

    1973-01-01

    Airframe/propulsion system interactions can strongly affect the stability and control of supersonic cruise aircraft. These interactions generate forces and moments similar in magnitude to those produced by the aerodynamic controls, and can cause significant changes in vehicle damping and static stability. This in turn can lead to large aircraft excursions or high pilot workload, or both. For optimum integration of an airframe and its jet propulsion system, these phenomena may have to be taken into account.

  2. Design and software aspects for the control system of the 30 m MRT.

    NASA Astrophysics Data System (ADS)

    Schraml, J.; Brunswig, W.; Juen, G.

    1984-01-01

    The 30 m Millimeter Radiotelescope (MRT) will have a beamwidth of less than 10arcsec when operated at a wavelength of 1.2 mm. It is an open air telescope located on a mountain ridge in southern Spain. There the instrument is exposed to severe environmental influences, especially wind and temperature changes. The pointing and tracking accuracy required is of the order of a few seconds of arc. Simulations have shown that these specifications cannot be met with conventional servo design. An improvement of performance can be obtained applying the modern concept of state control. The state controller needs the acquisition of data about position and velocity at several points of the instrument in real time. Additionally the state controller requires repetition rates of a few milliseconds, in which the data have to be read, converted and the servo algorithms calculated. This is performed by microprocessors operating in CAMAC crates close to the driving system. The whole system is controlled by two identical computers. One usually controls the antenna and data acquisition from the receivers, the other can be used for data analysis or as a backup controller. All receivers are connected via CAMAC, too. Special software tools have been developed for the use of this system. They allow an easy access to the variety of different process control items needed to drive the complete system. They have proved to be a powerful aid in developing the process control hardware and in the installation phase. They will be used for the communication between the operators and the system. In the development of the system the possibility of expanding the system to remote observing has been kept open.

  3. Relationship between bacterial diversity and function under biotic control: the soil pesticide degraders as a case study

    PubMed Central

    Monard, Cécile; Vandenkoornhuyse, Philippe; Le Bot, Barbara; Binet, Françoise

    2011-01-01

    In soil, the way biotic parameters impact the relationship between bacterial diversity and function is still unknown. To understand these interactions better, we used RNA-based stable-isotope probing to study the diversity of active atrazine-degrading bacteria in relation to atrazine degradation and to explore the impact of earthworm-soil engineering with respect to this relationship. Bulk soil, burrow linings and earthworm casts were incubated with 13C-atrazine. The pollutant degradation was quantified by liquid chromatography–mass spectrometry for 8 days, whereas active atrazine degraders were identified at 2 and 8 days by sequencing the 16S ribosomal RNA in the 13C-RNA fractions from the three soil microsites. An original diversity of atrazine degraders was found. Earthworm soil engineering greatly modified the taxonomic composition of atrazine degraders with dominance of α-, β- and γ-proteobacteria in burrow linings and of Actinobacteria in casts. Earthworm soil bioturbation increased the γ-diversity of atrazine degraders over the soil microsites generated. Atrazine degradation was enhanced in burrow linings in which primary atrazine degraders, closely related to Pelomonas aquatica, were detected only 2 days after atrazine addition. Atrazine degradation efficiency was not linearly related to the species richness of degraders but likely relied on keystone species. By enhancing soil heterogeneity, earthworms sustained high phylogenetic bacterial diversity and exerted a biotic control on the bacterial diversity–function relationships. Our findings call for future investigations to assess the ecological significance of biotic controls on the relationships between diversity and function on ecosystem properties and services (for example, soil detoxification) at larger scales. PMID:21160539

  4. Improvement in the control aspect of laser frequency stabilization for SUNLITE project

    NASA Technical Reports Server (NTRS)

    Zia, Omar

    1992-01-01

    Flight Electronics Division of Langley Research Center is developing a spaceflight experiment called the Stanford University and NASA Laser In-Space Technology (SUNLITE). The objective of the project is to explore the fundamental limits on frequency stability using an FM laser locking technique on a Nd:YAG non-planar ring (free-running linewidth of 5 KHz) oscillator in the vibration free, microgravity environment of space. Compact and automated actively stabilized terahertz laser oscillators will operate in space with an expected linewidth of less than 3 Hz. To implement and verify this experiment, NASA engineers have designed and built a state of the art, space qualified high speed data acquisition system for measuring the linewidth and stability limits of a laser oscillator. In order to achieve greater stability and better performance, an active frequency control scheme requiring the use of a feedback control loop has been applied. In the summer of 1991, the application of control theory in active frequency control as a frequency stabilization technique was investigated. The results and findings were presented in 1992 at the American Control Conference in Chicago, and have been published in Conference Proceedings. The main focus was to seek further improvement in the overall performance of the system by replacing the analogue controller by a digital algorithm.

  5. Closely packed and aspect-ratio-controlled antireflection subwavelength gratings on GaAs using a lenslike shape transfer.

    PubMed

    Song, Young Min; Bae, Si Young; Yu, Jae Su; Lee, Yong Tak

    2009-06-01

    We report a simple and low-cost fabrication of antireflection subwavelength grating (SWG) structures on GaAs using the lenslike shape transfer by a holographic lithography and a reflowed photoresist mask. The use of an additional thermal reflow process enhances the close packing of two-dimensional SWGs with a conical shape. The aspect ratio of conical SWG was also controlled easily by adjusting the rf power during the dry etch process. The fabricated SWGs exhibited low reflection properties over a wide spectral range, in agreement with the calculated values using by a rigorous coupled-wave analysis simulation. PMID:19488154

  6. Ethical aspects and dilemmas of fertility control of unwanted wildlife: an animal welfarist's perspective.

    PubMed

    Oogjes, G

    1997-01-01

    Proposals to manipulate the fertility of wild, free-living animals extend the domination humans already exercise over domesticated animals. Current lethal methods for population control include poisoning, trapping, hunting, dogging, shooting, explosives, fumigants, and deliberately introduced disease. Animal welfare interests are based on individual animal suffering, but those interests are often overshadowed by labelling of groups of animals as pests, resource species, national emblem or endangered species. Public concern for animal welfare and acceptance of new population control methods will be influenced by such labels. The animal welfare implications of new population control technology must be balanced against the existing inhumane lethal methods used. It will be difficult to resolve the dilemma of a mechanism for disseminating a fertility control agent that will cause some animal suffering (e.g. a genetically-manipulated myxoma virus for European rabbits), yet may reduce future rabbit populations and therefore the number suffering from lethal methods. An Animal Impact Statement is proposed as a tool to assist debate during development of fertility control methods and for decision making prior to their use. A comprehensive and objective Animal Impact Statement may introduce an ethic that moves the pendulum from attitudes that allow sentient animals to be destroyed by any and all available means, towards a more objective selection of the most effective and humane methods. PMID:9109207

  7. Thyristor controlled series compensation: Some aspects of different circuit parameters and voltage stability margin

    SciTech Connect

    Besanger, Y.; Maginier, S.; Hadjsaid, N.; Feuillet, R.

    1995-12-31

    Variable series compensation allows power transfers to be increased and controlled in the UHV transmission lines. Much attention has been focused recently on using Power Electronics to improve the speed control of variable series compensation. Several devices have been presented these last years. The main circuit studied at present is the Thyristor Controlled Series Compensator (TCSC). This paper presents a time domain simulation of the TCSC circuit. The analysis is performed by a simulation program based on the Bergeron`s method. The study of the TCSC module operation in an electric line shows that TCSC modules enable the transmission line performance to be improved (variable compensation), without introducing too many harmonics the system.

  8. Aspects of model-based rocket engine condition monitoring and control

    NASA Technical Reports Server (NTRS)

    Karr, Gerald R.; Helmicki, Arthur J.

    1994-01-01

    A rigorous propulsion system modelling method suitable for control and condition monitoring purposes is developed. Previously developed control oriented methods yielding nominal models for gaseous medium propulsion systems are extended to include both nominal and anomalous models for liquid mediums in the following two ways. First, thermodynamic and fluid dynamic properties for liquids such as liquid hydrogen are incorporated into the governing equations. Second, anomalous conditions are captured in ways compatible with existing system theoretic design tools so that anomalous models can be constructed. Control and condition monitoring based methods are seen as an improvement over some existing modelling methods because such methods typically do not rigorously lead to low order models nor do they provide a means for capturing anomalous conditions. Applications to the nominal SSME HPFP and degraded HPFP serve to illustrate the approach.

  9. Top-down and bottom-up control on bacterial diversity in a western Norwegian deep-silled fjord.

    PubMed

    Storesund, Julia E; Erga, Svein Rune; Ray, Jessica L; Thingstad, T Frede; Sandaa, Ruth-Anne

    2015-07-01

    We investigated the relationship between viruses and co-occurring bacterial communities in the Sognefjord, a deep-silled fjord in Western Norway. A combination of flow cytometry and automated ribosomal intergenic spacer analysis (ARISA) was used to assess prokaryote and viral abundances, and bacterial diversity and community composition, respectively, in depth profiles and at two different sampling seasons (November and May). With one exception, bacterial diversity did not vary between samples regardless of depth or season. The virus and prokaryote abundances as well as bacterial community composition, however, varied significantly with season and depth, suggesting a link between the Sognefjord viral community and potential bacterial host community diversity. To our knowledge, these findings provide the first description of microbial communities in the unique Sognefjord ecosystem, and in addition are in agreement with the simple model version of the 'Killing the Winner' theory (KtW), which postulates that microbial community diversity is a feature that is essentially top-down controlled by viruses, while community composition is bottom-up controlled by competition for limiting growth substrates. PMID:26170047

  10. My House of Value: School Intervention Programme Investigating Aspects of Self-Knowing, Knowing of the Other, Identity, Diversity and Interaction

    ERIC Educational Resources Information Center

    Hadjitheodoulou-Loizidou, Pavlina; Fokaidou, Marianna; Papamarkou, Stelios

    2012-01-01

    The project "My house of value" was implemented at a fourth grade primary school classroom for 10-year-old students in Nicosia, Cyprus. The main goal of the project was to examine how pupils realise identity and diversity in their broad sense, how they deal with stereotypical thoughts and how they understand interaction in both positive and

  11. Comparing temporal aspects of visual, tactile, and microstimulation feedback for motor control

    PubMed Central

    Godlove, Jason; OBrien, Erin; Batista, Aaron

    2014-01-01

    Objectives Current brain-computer interfaces (BCIs) rely on visual feedback, requiring sustained visual attention to use the device. Improvements to BCIs may stem from the development of an effective way to provide quick feedback independent of vision. Tactile stimuli, either delivered on the skin surface, or directly to the brain via microstimulation in somatosensory cortex, could serve that purpose. We examined the effectiveness of vibrotactile stimuli and microstimulation as a means of non-visual feedback by using a fundamental element of feedback: the ability to react to a stimulus while already in motion. Approach Human and monkey subjects performed a center-out reach task which was, on occasion, interrupted with a stimulus cue that instructed a change in reach target. Main results Subjects generally responded faster to tactile cues than to visual cues. However, when we delivered cues via microstimuation in a monkey, its average response was slower than that for both tactile and visual cues. Significance Tactile and microstimulation feedback can be used to rapidly adjust movements mid-flight. The relatively slow speed of microstimulation raises some interesting questions and warrants further investigation. Overall, these results highlight the importance of considering temporal aspects of feedback when designing alternative forms of feedback for brain-computer interfaces. PMID:25028989

  12. Comparing temporal aspects of visual, tactile, and microstimulation feedback for motor control

    NASA Astrophysics Data System (ADS)

    Godlove, Jason M.; Whaite, Erin O.; Batista, Aaron P.

    2014-08-01

    Objectives. Current brain-computer interfaces (BCIs) rely on visual feedback, requiring sustained visual attention to use the device. Improvements to BCIs may stem from the development of an effective way to provide quick feedback independent of vision. Tactile stimuli, either delivered on the skin surface, or directly to the brain via microstimulation in somatosensory cortex, could serve that purpose. We examined the effectiveness of vibrotactile stimuli and microstimulation as a means of non-visual feedback by using a fundamental element of feedback: the ability to react to a stimulus while already in motion. Approach. Human and monkey subjects performed a center-out reach task which was, on occasion, interrupted with a stimulus cue that instructed a change in reach target. Main results. Subjects generally responded faster to tactile cues than to visual cues. However, when we delivered cues via microstimuation in a monkey, its response was slower on average than for both tactile and visual cues. Significance. Tactile and microstimulation feedback can be used to rapidly adjust movements mid-flight. The relatively slow speed of microstimulation is surprising and warrants further investigation. Overall, these results highlight the importance of considering temporal aspects of feedback when designing alternative forms of feedback for BCIs.

  13. Afferent and Efferent Aspects of Mandibular Sensorimotor Control in Adults Who Stutter

    ERIC Educational Resources Information Center

    Daliri, Ayoub; Prokopenko, Roman A.; Max, Ludo

    2013-01-01

    Purpose: Individuals who stutter show sensorimotor deficiencies in speech and nonspeech movements. For the mandibular system, the authors dissociated the sense of kinesthesia from the efferent control component to examine whether kinesthetic integrity itself is compromised in stuttering or whether deficiencies occur only when generating motor…

  14. Molecular and genetic aspects of controlling the soilborne necrotrophic pathogens Rhizoctonia and Pythium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The soilborne necrotrophic pathogens Rhizoctonia and Pythium infect a wide range of crops in the US and worldwide. These pathogens pose challenges to growers because the diseases they cause are not adequately controlled by fungicides, rotation or, for many hosts, natural genetic resistance. Although...

  15. Some aspects of aerodynamic flow control using synthetic-jet actuation.

    PubMed

    Glezer, Ari

    2011-04-13

    Aerodynamic flow control effected by interactions of surface-mounted synthetic (zero net mass flux) jet actuators with a local cross flow is reviewed. These jets are formed by the advection and interactions of trains of discrete vortical structures that are formed entirely from the fluid of the embedding flow system, and thus transfer momentum to the cross flow without net mass injection across the flow boundary. Traditional approaches to active flow control have focused, to a large extent, on control of separation on stalled aerofoils by means of quasi-steady actuation within two distinct regimes that are characterized by the actuation time scales. When the characteristic actuation period is commensurate with the time scale of the inherent instabilities of the base flow, the jets can effect significant quasi-steady global modifications on spatial scales that are one to two orders of magnitude larger than the scale of the jets. However, when the actuation frequency is sufficiently high to be decoupled from global instabilities of the base flow, changes in the aerodynamic forces are attained by leveraging the generation and regulation of 'trapped' vorticity concentrations near the surface to alter its aerodynamic shape. Some examples of the utility of this approach for aerodynamic flow control of separated flows on bluff bodies and fully attached flows on lifting surfaces are also discussed. PMID:21382826

  16. Afferent and Efferent Aspects of Mandibular Sensorimotor Control in Adults Who Stutter

    ERIC Educational Resources Information Center

    Daliri, Ayoub; Prokopenko, Roman A.; Max, Ludo

    2013-01-01

    Purpose: Individuals who stutter show sensorimotor deficiencies in speech and nonspeech movements. For the mandibular system, the authors dissociated the sense of kinesthesia from the efferent control component to examine whether kinesthetic integrity itself is compromised in stuttering or whether deficiencies occur only when generating motor

  17. Agronomic aspects of strip intercropping lettuce with alyssum for biological control of aphids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic growers in California typically devote 5 to 10% of the area in lettuce (Lactuca sativa L.) fields to insectary strips of alyssum (Lobularia maritime (L.) Desv.) to attract syrphid flies (Syrphidae) whose larvae provide biological control of aphids. A 2-year study with organic romaine lettuc...

  18. The MCAO systems within LINC-NIRVANA: control aspects beyond wavefront correction

    NASA Astrophysics Data System (ADS)

    Bertram, T.; Arcidiacono, C.; Berwein, J.; Bizenberger, P.; Briegel, F.; Diolaiti, E.; Farinato, J.; Gssler, W.; Herbst, T. M.; Hofferbert, R.; Kittmann, F.; Krster, M.; Ragazzoni, R.; Schreiber, L.; Trowitzsch, J.; Viotto, V.

    2010-07-01

    LINC-NIRVANA is the near-infrared homothetic imaging camera for the Large Binocular Telescope. Once operational, it will provide an unprecedented combination of angular resolution, sensitivity and field of view. Its layer-oriented MCAO systems (one for each arm of the interferometer) are conjugated to the ground layer and an additional layer in the upper atmosphere. In this contribution MCAO wavefront control is discussed in the context of the overall control scheme for LINC-NIRVANA. Special attention is paid to a set of auxiliary control tasks which are mandatory for MCAO operation: The Fields of View of each wavefront sensor in the instrument have to be derotated independent from each other and independently from the science field. Any wavefront information obtained by the sensors has to be matched to the time invariant modes of the deformable mirrors in the system. The tip/tilt control scheme is outlined, in which atmospheric, but also instrumental tip/tilt corrections are sensed with the high layer wavefront sensor and corrected by the adaptive secondary mirror of the LBT. Slow image motion effects on the science detector have to be considered, which are caused by flexure in the non-common path between AO and the science camera, atmospheric differential refraction, and alignment tolerances of the derotators. Last but not least: The sensor optics (pyramids) have to be accurately positioned at the images of natural reference stars.

  19. Legal Aspects of Control of Student Activities by Public School Officials.

    ERIC Educational Resources Information Center

    Reutter, E. Edmund, Jr.

    This monograph reviews and analyzes relevant decisions dealing with the control of student activities by public school authorities. The report focuses on recent court cases that reaffirm, amplify, or extend entrenched constitutional and common law principles undergirding the public educational system in the United States. After setting the legal

  20. Quality control aspects of herbs and botanicals in developing countries: Coleus forskohlii Briq a case study

    PubMed Central

    Tamboli, Ennus Tajuddin; Chester, Karishma; Ahmad, Sayeed

    2015-01-01

    Objective: Current trend of commercialization of herbal medicines draw a huge need of maintaining their quality. The declaration of quality, safety and efficacy of medicinal plants as well as poly-herbal formulations has become an important issue. Hence, qualitative and quantitative analysis of herbal drugs and formulations viz., fingerprint profiles and quantification of the various markers become key factors of quality control. Materials and Methods: Present investigation is a detailed report for quality control of well-known herb Coleus forskohlii Briq, which includes physicochemical parameter determination, safety evaluation, microscropical evaluation, and chromatographic fingerprinting as well. Results: Physico-chemical characters were evaluated according to Indian Pharmacopoeia, further microscopic evaluation of transverse section of Coleus reveals that periderm, secondary phloem, and wide secondary xylem cylinder, which occupies major portion of the root fragmentary. Chromatographic fingerprint profiles of Coleus have been generated, and a marker based standardization strategy was adopted; using different analytical technique like high-performance thin layer chromatography, high-performance liquid chromatography and gas chromatography-mass spectroscopy to maintain quality and ensure safety as well as efficacy. Conclusion: These advancements in modern techniques of analysis can lead to effective quality control of Coleus as well as other herbs. Present report can act as pioneer for quality control of modern herbal medicine. PMID:26681877

  1. Cost-efficient and flexible fabrication of rectangular-shaped microlens arrays with controllable aspect ratio and spherical morphology

    NASA Astrophysics Data System (ADS)

    Hu, Yang; Yang, Qing; Chen, Feng; Bian, Hao; Deng, Zefang; Du, Guangqing; Si, Jinhai; Yun, Feng; Hou, Xun

    2014-02-01

    This paper presents a cost-efficient and flexible approach to the development of controllable-shape concave and convex microlens arrays by using femtosecond laser wet etch and replication techniques. Periodic concave rectangular-shaped microlens arrays with different length-width ratios were achieved by firstly introducing periodic microcraters on silica glass using an 800 nm femtosecond laser, and subsequently enlarging the craters into microlens with smooth curved surfaces in hydrofluoric (HF) acid solution. The concave microlens can serve as molds of replication to obtain convex microlenses on polymers. Over 10,000 rectangular-shaped concave and convex microlens with controllable aspect ratio, high fill factor and spherical morphology can be fabricated in 5 h. A simulation result and a projection experiment result verify the optical performance of these rectangular-shaped spherical microlens arrays (MLAs).

  2. Theoretic aspects of the identification of the parameters in the optimal control model

    NASA Technical Reports Server (NTRS)

    Vanwijk, R. A.; Kok, J. J.

    1977-01-01

    The identification of the parameters of the optimal control model from input-output data of the human operator is considered. Accepting the basic structure of the model as a cascade of a full-order observer and a feedback law, and suppressing the inherent optimality of the human controller, the parameters to be identified are the feedback matrix, the observer gain matrix, and the intensity matrices of the observation noise and the motor noise. The identification of the parameters is a statistical problem, because the system and output are corrupted by noise, and therefore the solution must be based on the statistics (probability density function) of the input and output data of the human operator. However, based on the statistics of the input-output data of the human operator, no distinction can be made between the observation and the motor noise, which shows that the model suffers from overparameterization.

  3. [Procedural and developmental aspects of impulse-control disorders in child and adolescent schizophrenia].

    PubMed

    Golik, A N

    2000-01-01

    200 schizophrenic patients (130 men, 70 women), which had fallen ill at the age of 4-25 years were examined in outpatient clinic. Either on the separate stages of the disease or during all its course the patients had the following impuls-control disorders: of eating--14 patients (7.0%), sexual drive--56 cases (28.0%), self-preservation--37 (18.5%), alcoholism--76 (38.0%), dromomania--38 (19.0%), pyromania--2 (1.0%), kleptomania--4 (2.0%). By the mechanisms of the disorders' development there were impulsive, obsessive and compulsive ones. The author also qualified the morbid impuls-control disorders (87 patients--43.5%) and the evolutive ones (61-30.5%). Morbid signs were considered in terms of the comorbid phenomena combined with the productive and negative symptoms of basic disease. Evolutive manifestations are deviations of ontogenesis which didn't achieve a pathologic form. PMID:10849962

  4. Authentic and Hubristic Pride: Differential Relations to Aspects of Goal Regulation, Affect, and Self-Control

    PubMed Central

    Carver, Charles S.; Johnson, Sheri L.

    2010-01-01

    This study examines the relationships of trait-like tendencies towards authentic and hubristic pride (Tracy & Robins, 2004) with goal-regulation tendencies, affective tendencies, and impulsive traits. Undergraduates (n = 936) completed the 14-item measure of authentic and hubristic pride (Tracy & Robins, 2007b) and a battery of other self-report measures. The two types of pride correlated with distinct profiles of goal regulation tendencies, affective tendencies, and self-control. Authentic pride correlated with measures of self-control, whereas hubristic pride was related to measures of impulsivity and aggression. Overall, the differential pattern of correlations fits with a model in which authentic pride is tied to adaptive achievement and goal engagement, whereas hubristic pride is tied to extrinsic values of public recognition and social dominance. PMID:21769159

  5. Engineering aspects of a thermal control subsystem for the 25 kW power module

    NASA Technical Reports Server (NTRS)

    Schroeder, P. E.

    1979-01-01

    The paper presents the key trade study results, analysis results, and the recommended thermal control approach for the 25 kW power module defined by NASA. Power conversion inefficiencies and component heat dissipation results in a minimum heat rejection requirement of 9 kW to maintain the power module equipment at desired temperature levels. Additionally, some cooling capacity should be provided for user payloads in the sortie and free-flying modes. The baseline thermal control subsystem includes a dual-loop-pumped Freon-21 coolant with the heat rejected from deployable existing orbiter radiators. Thermal analysis included an assessment of spacecraft orientations, radiator shapes and locations, and comparison of hybrid heat pipe and all liquid panels.

  6. A case-control study of Hodgkin's disease in Brazil. I. Epidemiogic aspects.

    PubMed

    Kirchhoff, L V; Evans, A S; McClelland, K E; Carvalho, R P; Pannuti, C S

    1980-11-01

    A number of epidemiologic variables were investigated in a case-control interview study, conducted in São Paulo, Brazil, of 70 Hodgkin's disease (HD) patients, 70 tumor control subjects matched for age and sex, and 128 siblings of the patients. The major epidemiologic findings were a high percentage of total cases among children, with a high sex ratio, a relative predominance of the mixed cellularity histologic subtype, and a bimodal age-specific incidence curve with the highest rates among young adults and the elderly. When the matched controls were used as the comparison group, high socioeconomic status (SES) was found to be associated with an increased risk for HD (p = 0.001). On the basis of the case-sibling comparison, an association between prior tonsillectomy and risk for HD was found (p = 0.04), and the relative risk for HD among tonsillectomized persons as compared to individuals who had not had the operation was 2.5. Other variables, including sibship size, birth order, marital status, occupational exposure, prior use of amphetamines or diphenylhydantoin, intensity of exposure to children and history of viral illnesses were not found to be determinants of risk for HD in this study. PMID:7435488

  7. Does the habitat structure control the distribution and diversity of the Odonatofauna?

    PubMed

    Souza, A M; Fogaça, F N O; Cunico, A M; Higuti, J

    2015-08-01

    The statement that the habitat complexity and structure govern the abundance and diversity of biological communities has been widely investigated. In this context, we assumed the hypothesis of habitat heterogeneity, that is, the higher habitat complexity leads to greater diversity of Odonata. In addition, we analyzed the influence of habitat structure on the distribution of this community, and evaluated the effects of abiotic variables. Odonata larvae were collected with sieves and by electrofishing in ten neotropical streams belonging to the Pirapó River basin. Forty species of Odonata were registered, which were distributed in eight families, Libellulidae stood out with the highest richness. The high gamma diversity and distribution of Odonata were associated with habitat heterogeneity in these streams. However, the abiotic variables also seem to affect the distribution of Odonata species, in view of the impact of the land use in the vicinity of streams. PMID:26421772

  8. Software Design Aspects and First Test Results of VLT Survey Telescope Control System

    NASA Astrophysics Data System (ADS)

    Brescia, M.; Schipani, P.; Marty, L.; Capaccioli, M.

    2006-08-01

    The 2.6 m VLT Survey Telescope (VST) is going to be installed at Cerro Paranal (Chile) as a powerful survey instrument for the ESO VLT. The tightest requirements to be respected for such a telescope, (large field of view of 1x1, pixel scale of 0.21 arcsec/pixel, and hosted in a one of the best worldwide astronomical sites), are basically very high performances of active optics and autoguiding systems and an excellent axes control, in order to obtain the best overall image quality of the telescope. The VST active optics software must basically provide the analysis of the image coming from the 10x10 subpupils Shack Hartmann wavefront sensor and the calculation of primary mirror forces and secondary mirror displacements to correct the intrinsic aberrations of the optical system and the ones originated for thermal or gravity reasons. The algorithm to select the guide star depends on the specific geometry of the adapter system. The adapter of the VST hosts many devices handled by the overall telescope control software: a probe system to select the guide star realized with motions in polar coordinates, a pickup mirror to fold the light to the image analysis and guiding cameras, a selectable reference light system and a focusing device. All these devices deeply interface with autoguiding, active optics and field rotation compensation systems. A reverse engineering approach mixed to the integration of new specific solutions has been fundamental to match the ESO commitments in terms of software re-use, in order to smoothen the integration of a new telescope designed and built by an external institute in the ESO environment. The control software architecture, the simulation code to validate the results and the status of work are here described. This paper includes also first results of preliminary tracking tests performed at the VST integration site for azimuth, altitude and rotator axes, that already match system quality requirements.

  9. Differential control of temporal and spatial aspects of cockroach leg coordination.

    PubMed

    Couzin-Fuchs, E; Gal, O; Holmes, P; Ayali, A

    2015-08-01

    Ensembles of neuronal networks and sensory pathways participate in controlling the kinematic and dynamic parameters of animal movement necessary to achieve motor coordination. Determining the relative contribution of proprioceptive feedback is essential for understanding how animals sustain stable, coordinated locomotion in complex natural environments. Here, we focus on the role of chordotonal organs (COs), proprioceptors found in insect legs, in the spatial and temporal regulation of walking. We compare gait parameters of intact cockroaches (Periplaneta americana) and sensory-impaired ones, injected with pymetrozine, a chemical previously shown to abolish CO function in locusts. We verify that afferent CO activity in pymetrozine-treated cockroaches is inhibited, and analyze the effect of this sensory deprivation on inter-leg coordination. We find significant changes in tarsi placement and leg path trajectories after pymetrozine treatment. Leg touchdown accuracy, measured from relative tarsi positions of adjacent legs, is reduced in treated animals. Interestingly, despite poorer spatial coordination in both stance and swing, temporal properties of the gait remain largely the same as in the intact preparations, apart from changes in ipsilateral phase differences between front and middle legs. These findings provide insights into the role of COs in insect gait control and establish pymetrozine as a useful tool for further studies of insect locomotion. PMID:26086675

  10. Aspects of satellite imagery exploration in GIS-based command and control real-time technologies

    NASA Astrophysics Data System (ADS)

    Levin, Eugene; Jannson, Tomasz P.; Kostrzewski, Andrew A.

    2002-08-01

    The tremendous increase in satellite imagery resolution and accuracy has made it reasonable to exploit such imagery in GIS-based command and control, fusing data streams from UAV/UGV and satellite sensors for C4ISR systems. To fuse imagery from satellite and tactical sensors in real time, the authors apply probabilistic analysis, polyquadrically interpolating evidential reasoning about non-numeric tactical factors and superimposing them on Digital Terrain Models and satellite imagery. Doing this in real time for C4ISR requires highly parallel computation, implemented on Video/Imagery Super-Parallel and Supercomputer-Path (VISP) hardware. Another approach is integrated view analysis for purposes of command decision making missions, making use of GIS environments, Dynamic Time Multiplexed Holographic (DTMH) screens, and 3-D projection for precise visualization of accurate GIS-based imagery. This technology incorporates non-numeric real-time information into the command and control processes with simultaneous integrated 3-D views. Theory and experiment both indicate that the methods and algorithms described here are feasible.

  11. Host and parasite diversity jointly control disease risk in complex communities

    PubMed Central

    Johnson, Pieter T. J.; Preston, Daniel L.; Hoverman, Jason T.; LaFonte, Bryan E.

    2013-01-01

    Host–parasite interactions are embedded within complex communities composed of multiple host species and a cryptic assemblage of other parasites. To date, however, surprisingly few studies have explored the joint effects of host and parasite richness on disease risk, despite growing interest in the diversity–disease relationship. Here, we combined field surveys and mechanistic experiments to test how transmission of the virulent trematode Ribeiroia ondatrae was affected by the diversity of both amphibian hosts and coinfecting parasites. Within natural wetlands, host and parasite species richness correlated positively, consistent with theoretical predictions. Among sites that supported Ribeiroia, however, host and parasite richness interacted to negatively affect Ribeiroia transmission between its snail and amphibian hosts, particularly in species-poor assemblages. In laboratory and outdoor experiments designed to decouple the relative contributions of host and parasite diversity, increases in host richness decreased Ribeiroia infection by 11–65%. Host richness also tended to decrease total infections by other parasite species (four of six instances), such that more diverse host assemblages exhibited ∼40% fewer infections overall. Importantly, parasite richness further reduced both per capita and total Ribeiroia infection by 15–20%, possibly owing to intrahost competition among coinfecting species. These findings provide evidence that parasitic and free-living diversity jointly regulate disease risk, help to resolve apparent contradictions in the diversity–disease relationship, and emphasize the challenges of integrating research on coinfection and host heterogeneity to develop a community ecology-based approach to infectious diseases. PMID:24082092

  12. Assessing genetic diversity of wild and hatchery samples of the Chinese sucker (Myxocyprinus asiaticus) by the mitochondrial DNA control region.

    PubMed

    Wu, Jiayun; Wu, Bo; Hou, Feixia; Chen, Yongbai; Li, Chong; Song, Zhaobin

    2016-03-01

    To restore the natural populations of Chinese sucker (Myxocyprinus asiaticus), a hatchery release program has been underway for nearly 10 years. Using DNA sequences of the mitochondrial control region, we assessed the genetic diversity and genetic structure among samples collected from three sites of the wild population as well as from three hatcheries. The haplotype diversity of the wild samples (h = 0.899-0.975) was significantly higher than that of the hatchery ones (h = 0.296-0.666), but the nucleotide diversity was almost identical between them (π = 0.0170-0.0280). Relatively high gene flow was detected between the hatchery and wild samples. Analysis of effective population size indicated that M. asiaticus living in the Yangtze River has been expanding following a bottleneck in the recent past. Our results suggest the hatchery release programs for M. asiaticus have not reduced the genetic diversity, but have influenced the genetic structure of the species in the upper Yangtze River. PMID:25242190

  13. Source, significance, and control of indoor microbial aerosols: human health aspects.

    PubMed Central

    Spendlove, J C; Fannin, K F

    1983-01-01

    The usual profile of indoor microbial aerosols probably has little meaning to healthy people. However, hazardous microbial aerosols can penetrate buildings or be generated within them; in either case, they can have significant adverse effects on human health. These aerosols can be controlled to some extent by eliminating or reducing their sources. In this regard, careful consideration should be given in building construction to the design of ventilation and air-conditioning systems and to the flooring material, so that these systems and the flooring material will not act as microbial reservoirs. It is evident that in spite of the considerable body of data available on indoor microbial aerosols, little is known of their true significance to human health except in terms of overt epidemic disease. Continued research is needed in this area, particularly in respect to situations of high risk in such locations as hospitals and schools for young children. PMID:6867255

  14. Contamination control aspects of attaching waste drums to the WIPP Waste Characterization Chamber

    SciTech Connect

    Rubick, L.M.; Burke, L.L.

    1998-12-31

    Argonne National Laboratory West (ANL-W) is verifying the characterization and repackaging of contact-handled transuranic (CH-TRU) mixed waste in support of the Waste Isolation Pilot Program (WIPP) project located in Carlsbad, New Mexico. The WIPP Waste Characterization Chamber (WCC) was designed to allow opening of transuranic waste drums for this process. The WCC became operational in March of 1994 and has characterized approximately 240 drums of transuranic waste. The waste drums are internally contaminated with high levels of transuranic radionuclides. Attaching and detaching drums to the glove box posed serious contamination control problems. Prior to characterizing waste, several drum attachment techniques and materials were evaluated. An inexpensive HEPA filter molded into the bagging material helps with venting during detachment. The current techniques and procedures used to attach and detach transuranic waste drums to the WCC are described.

  15. Two aspects of feedforward postural control: anticipatory postural adjustments and anticipatory synergy adjustments

    PubMed Central

    Klous, Miriam; Mikulic, Pavle

    2011-01-01

    We used the framework of the uncontrolled manifold hypothesis to explore the relations between anticipatory synergy adjustments (ASAs) and anticipatory postural adjustments (APAs) during feedforward control of vertical posture. ASAs represent a drop in the index of a multimuscle-mode synergy stabilizing the coordinate of the center of pressure in preparation to an action. ASAs reflect early changes of an index of covariation among variables reflecting muscle activation, whereas APAs reflect early changes in muscle activation levels averaged across trials. The assumed purpose of ASAs is to modify stability of performance variables, whereas the purpose of APAs is to change magnitudes of those variables. We hypothesized that ASAs would be seen before APAs and that this finding would be consistent with regard to the muscle-mode composition defined on the basis of different tasks and phases of action. Subjects performed a voluntary body sway task and a quick, bilateral shoulder flexion task under self-paced and reaction time conditions. Surface muscle activity of 12 leg and trunk muscles was analyzed to identify sets of 4 muscle modes for each task and for different phases within the shoulder flexion task. Variance components in the muscle-mode space and indexes of multimuscle-mode synergy stabilizing shift of the center of pressure were computed. ASAs were seen ?100150 ms prior to the task initiation, before APAs. The results were consistent with respect to different sets of muscle modes defined over the two tasks and different shoulder flexion phases. We conclude that the preparation for a self-triggered postural perturbation is associated with two types of anticipatory adjustments, ASAs and APAs. They reflect different feedforward processes within the hypothetical hierarchical control scheme, resulting in changes in patterns of covariation of elemental variables and in their patterns averaged across trials, respectively. The results show that synergies quantified using dissimilar sets of muscle modes show similar feedforward changes in preparation to action. PMID:21389305

  16. Two aspects of feedforward postural control: anticipatory postural adjustments and anticipatory synergy adjustments.

    PubMed

    Klous, Miriam; Mikulic, Pavle; Latash, Mark L

    2011-05-01

    We used the framework of the uncontrolled manifold hypothesis to explore the relations between anticipatory synergy adjustments (ASAs) and anticipatory postural adjustments (APAs) during feedforward control of vertical posture. ASAs represent a drop in the index of a multimuscle-mode synergy stabilizing the coordinate of the center of pressure in preparation to an action. ASAs reflect early changes of an index of covariation among variables reflecting muscle activation, whereas APAs reflect early changes in muscle activation levels averaged across trials. The assumed purpose of ASAs is to modify stability of performance variables, whereas the purpose of APAs is to change magnitudes of those variables. We hypothesized that ASAs would be seen before APAs and that this finding would be consistent with regard to the muscle-mode composition defined on the basis of different tasks and phases of action. Subjects performed a voluntary body sway task and a quick, bilateral shoulder flexion task under self-paced and reaction time conditions. Surface muscle activity of 12 leg and trunk muscles was analyzed to identify sets of 4 muscle modes for each task and for different phases within the shoulder flexion task. Variance components in the muscle-mode space and indexes of multimuscle-mode synergy stabilizing shift of the center of pressure were computed. ASAs were seen ? 100-150 ms prior to the task initiation, before APAs. The results were consistent with respect to different sets of muscle modes defined over the two tasks and different shoulder flexion phases. We conclude that the preparation for a self-triggered postural perturbation is associated with two types of anticipatory adjustments, ASAs and APAs. They reflect different feedforward processes within the hypothetical hierarchical control scheme, resulting in changes in patterns of covariation of elemental variables and in their patterns averaged across trials, respectively. The results show that synergies quantified using dissimilar sets of muscle modes show similar feedforward changes in preparation to action. PMID:21389305

  17. Aspects of the neuroendocrine control of ovulation and broodiness in the domestic hen.

    PubMed

    Sharp, P J; MacNamee, M C; Talbot, R T; Sterling, R J; Hall, T R

    1984-12-01

    The neuroendocrine control of ovulation and broodiness in the domestic hen involves complex interactions between hypothalamic neuropeptides, neurotransmitters, and ovarian steroids which regulate the secretion of luteinizing hormone (LH) and prolactin. Nuclear progesterone receptor is localized in many neurons throughout the hypothalamus but is absent from LHRH neurons. Hence, the positive feedback action of progesterone on LH release is not mediated by a genomic mechanism within the LHRH neuron. Precursors of 5-hydroxytryptamine (5HT) and dopamine (DA) inhibit the preovulatory release of LH, while the turnover rates of these neurotransmitters in the anterior hypothalamus decrease when preovulatory levels of LH are at their highest. Further, a population of receptors for 5HT which occurs in the anterior hypothalamus in laying birds is absent in nonlaying, incubating hens. Taken together, these observations suggest that the preovulatory surge of LH is mediated by a transitory decrease in the inhibitory action of 5HT and possibly DA, on the secretion of LHRH. Neurons containing 5HT may play a role in the regulation of prolactin release and, more specifically, in the control of broodiness. Drugs which enhance the function of 5HT neurons stimulate prolactin release while increased prolactin secretion in incubating hens is associated with an increase in the turnover of 5HT in the anterior hypothalamus. No receptors for 5HT were demonstrable in the anterior pituitary gland, showing that the prolactin-releasing activity of 5HT must be mediated by a prolactin-releasing factor (PRF). A candidate for a physiological PRF is vasoactive intestinal polypeptide (VIP).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6151581

  18. Coupling Temperature Control with Electrochemically Modulated Liquid Chromatography: Fundamental Aspects and Applications

    SciTech Connect

    Lisa M. Ponton

    2004-12-19

    The primary focus of the doctoral research presented herein has been the integration of temperature control into electrochemically modulated liquid chromatography (EMLC). The combination of temperature control and the tunable characteristics of carbonaceous EMLC stationary phases have been invaluable in deciphering the subtleties of the retention mechanism. The effects of temperature and E{sub app} on the retention of several naphthalene disulfonates were therefore examined by the van' Hoff relationship. The results indicate that while the retention of both compounds is exothermic at levels comparable to that in many reversed-phase separations, the potential dependence of the separation is actually entropically affected in a manner paralleling that of several classical ion exchange systems. Furthermore, the retention of small inorganic anions at constant temperature also showed evidence of an ion exchange type of mechanism. While a more complete mechanistic description will come from examining the thermodynamics of retention for a wider variety of analytes, this research has laid the groundwork for full exploitation of temperature as a tool to develop retention rules for EMLC. Operating EMLC at elevated temperature and flow conditions has decreased analysis time and has enabled the separation of analytes not normally achievable on a carbon stationary phase. The separation of several aromatic sulfonates was achieved in less than 1 min, a reduction of analysis time by more than a factor of 20 as compared to room temperature separations. The use of higher operating temperatures also facilitated the separation of this mixture with an entirely aqueous mobile phase in less than 2 min. This methodology was extended to the difficult separation of polycyclic aromatic hydrocarbons on PGC. This study also brought to light the mechanistic implications of the unique retention behavior of these analytes through variations of the mobile phase composition.

  19. Clinical aspects of the control of plasma volume at microgravity and during return to one gravity

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.

    1996-01-01

    Plasma volume is reduced by 10-20% within 24-48 h of exposure to simulated or actual microgravity. The clinical importance of microgravity induced hypovolemia is manifested by its relationship with orthostatic intolerance and reduced maximal oxygen uptake (VO2max) after return to one gravity (1G). Since there is no evidence to suggest that plasma volume reduction during microgravity is associated with thirst or renal dysfunctions, a diuresis induced by an immediate blood volume shift to the central circulation appears responsible for microgravity-induced hypovolemia. Since most astronauts choose to restrict their fluid intake before a space mission, absence of increased urine output during actual space flight may be explained by low central venous pressure (CVP) which accompanies dehydration. Compelling evidence suggests that prolonged reduction in CVP during exposure to microgravity reflects a "resetting" to a lower operating point, which acts to limit plasma volume expansion during attempts to increase fluid intake. In ground based and space flight experiments, successful restoration and maintenance of plasma volume prior to returning to an upright posture may depend upon development of treatments that can return CVP to its baseline IG operating point. Fluid-loading and lower body negative pressure (LBNP) have not proved completely effective in restoring plasma volume, suggesting that they may not provide the stimulus to elevate the CVP operating point. On the other hand, exercise, which can chronically increase CVP, has been effective in expanding plasma volume when combined with adequate dietary intake of fluid and electrolytes. The success of designing experiments to understand the physiological mechanisms of and development of effective counter measures for the control of plasma volume in microgravity and during return to IG will depend upon testing that can be conducted under standardized controlled baseline conditions during both ground-based and space flight investigations.

  20. Clinical Aspects of the Control of Plasma Volume at Microgravity and During Return to One Gravity

    NASA Technical Reports Server (NTRS)

    Convertino, Victor A.

    1995-01-01

    Plasma volume is reduced by 10%-20% within 24 to 48 h of exposure to simulated or actual microgravity. The clinical importance of microgravity-induced hypovolemia is manifested by its relationship with orthostatic intolerance and reduced VO2max after return to one gravity (1G). Since there is no evidence to suggest plasma volume reduction during microgravity is associated with thirst or renal dysfunctions, a diuresis induced by an immediate blood volume shift to the central circulation appears responsible for microgravity-induced hypovolemia. Since most astronauts choose to restrict their fluid intake before a space mission, absence of increased urine output during actual spaceflight may be explained by low central venous pressure (CVP) which accompanies dehydration. Compelling evidence suggests that prolonged reduction in CVP during exposure to microgravity reflects a 'resetting' to a lower operating point which acts to limit plasma volume expansion during attempts to increase fluid intake. In groudbase and spaceflight experiments, successful restoration and maintenance of plasma volume prior to returning to an upright posture may depend upon development of treatments that can return CVP to its baseline 10 operating point. Fluid-loading and LBNP have not proved completely effective in restoring plasma volume, suggesting that they may not provide the stimulus to elevate the CVP operating point. On the other, exercise, which can chronically increase CVP, has been effective in expanding plasma volume when combined with adequate dietary intake of fluid and electrolytes. The success of designing experiments to understand the physiological mechanisms of and development of effective countermeasures for the control of plasma volume in microgravity and during return to one gravity will depend upon testing that can be conducted under standardized controlled baseline condi

  1. Social and cultural aspects of 'malaria' and its control in central Cte d'Ivoire

    PubMed Central

    Ess, Clmence; Utzinger, Jrg; Tschannen, Andres B; Raso, Giovanna; Pfeiffer, Constanze; Granado, Stefanie; Koudou, Benjamin G; N'Goran, Elizer K; Ciss, Guladio; Girardin, Olivier; Tanner, Marcel; Obrist, Brigit

    2008-01-01

    Background A sound local understanding of preventive measures and health-seeking behaviour is important for the effective control of malaria. The purpose of this study was to assess the knowledge, attitudes, practices and beliefs of 'malaria' and its control in two rural communities of central Cte d'Ivoire, and to examine associations between 'malaria' and the households' socioeconomic status. Methods A cross-sectional household survey was carried out, using a combination of qualitative and quantitative methods. People's socioeconomic status was estimated, employing a household asset-based approach. Results Malaria was identified as djkouadjo, the local folk name of the disease. Although people were aware of malaria-related symptoms and their association with mosquitoes, folk perceptions were common. In terms of treatment, a wide array of modern and traditional remedies was employed, often in combination. Individuals with a sound knowledge of the causes and symptoms of malaria continued to use traditional treatments and only a few people sleep under bed nets, whereas folk beliefs did not necessarily translate into refusal of modern treatments. Perceived causes of malaria were linked to the household's socioeconomic status with wealthier individuals reporting mosquitoes more frequently than poorer households. Bed nets were more frequently used in wealthier social strata, whereas other protective measures perceived to be cheaper were more prominent among the poorest. Conclusion Equitable access to resources at household, community and health system levels are essential in order to enable community members to prevent and treat malaria. There is a need for community-based approaches that match health care services with poor people's needs and resources. PMID:18973663

  2. Comparison of nematode communities in Baltic and North Sea sublittoral, permeable sands Diversity and environmental control

    NASA Astrophysics Data System (ADS)

    Urban-Malinga, Barbara; Hedtkamp, Stefanie I. C.; van Beusekom, Justus E. E.; Wiktor, Jzef; W?s?awski, Jan Marcin

    2006-10-01

    The structure of free-living nematode communities was investigated seasonally at two sandy locations representing typical shallow sublittoral, permeable environments of the North Sea and the Baltic Sea. At the Baltic study site the chlorophyll and organic carbon concentrations in the sediment were, on average, four times lower than at the North Sea. Highest nematode densities (1674-4100 ind. 10 cm -2) and a higher number of free-living nematode genera (66) were recorded in the North Sea (Baltic: 206-1227 ind. 10 cm -2, 30 genera). Despite lower salinity and lower food availability the less dense and less diverse Baltic nematode community was similar in generic composition to the North Sea community. At the North Sea site, all trophic groups according to Wieser's classification were present with omnivores/predators, dominated by Viscosia, prevailing and followed by epistrate-feeders. In the food-limited Baltic community, non-selective deposit feeders (mainly Ascolaimus, Axonolaimus and Daptonema) and omnivores/predators dominated by Enoplolaimus were the most abundant trophic groups while selective deposit feeders were absent or their contribution was negligible. An analysis of the vertical generic distribution revealed highest diversity of the Baltic community in deeper sediment layers, below the sediment surface affected by ripple migration and near the interface of oxic and anoxic conditions. The diversity pattern in the North Sea sediment was more variable but generally showed high diversity in the upper centimetre of the sediment. These observations suggest that food supply and sediment oxygenation are the most important factors influencing the vertical pattern of nematode generic diversity in sublittoral, permeable sands.

  3. Nuclear-Physics Aspects of Controlled Thermonuclear Fusion: Analysis of Promising Fuels and Gamma-Ray Diagnostics of Hot Plasma

    NASA Astrophysics Data System (ADS)

    Voronchev, V. T.; Kukulin, V. I.

    2000-12-01

    A brief survey of nuclear-physics aspects of the problems of controlled thermonuclear fusion is given. Attention is paid primarily to choosing and analyzing an optimal composition of a nuclear fuel, reliably extrapolating the cross sections for nuclear reactions to the region of low energies, and exploring gamma-ray methods (as a matter of fact, very promising methods indeed) for diagnostics of hot plasmas (three aspects that are often thought to be the most important ones). In particular, a comparative nuclear-physics analysis of hydrogen, DT, and DD thermonuclear fuels and of their alternatives in the form of D3He, D6Li, DT6Li, H6Li, H11B, and H9Be is performed. Their advantages and disadvantages are highlighted; a spin-polarized fuel is considered; and the current status of nuclear data on the processes of interest is analyzed. A procedure for determining cross sections for nuclear reactions in the deep-subbarrier region is discussed. By considering the example of low-energy D+6Li interactions, it is shown that, at ion temperatures below 100 keV, the inclusion of nuclear-structure factors leads to an additional enhancement of the rate parameters for the ( d, pt) and ( d, n?) channels by 10-40%. The possibility of using nuclear reactions that lead to photon emission as a means for determining the ion temperature of a thermonuclear plasma is discussed.

  4. Visceral leishmaniasis in Rio de Janeiro, Brazil: eco-epidemiological aspects and control.

    PubMed

    Marzochi, Mauro Celio de Almeida; Fagundes, Aline; Andrade, Moacir Vieira de; Souza, Marcos Barbosa de; Madeira, Maria de Ftima; Mouta-Confort, Eliame; Schubach, Armando de Oliveira; Marzochi, Keyla Belizia Feldman

    2009-01-01

    From 1977 (index case) to 2006, 87 cases of visceral leishmaniasis were confirmed in the municipality of Rio de Janeiro, Brazil, in periurban areas on the continental and coastal slopes of the Pedra Branca massif and the continental slopes of the Gericin massif. The majority (65.5%) of the patients were more than five years old, predominantly males (61.5%), but without any difference between the sexes below the age of 14 years. The overall fatality rate was 10.4%. Two cases of visceral leishmaniasis/human immunodeficiency virus coinfection were detected. Leishmania chagasi was isolated from human and canine cases. The associations between the presence of phlebotomines and human and canine migrations, disorderly occupation involving degradation of environmental preservation areas and poor socioeconomic conditions may have created a favorable setting for the establishment and propagation of the disease. Close epidemiological surveillance associated with traditional control measures and others (active case researches, land clearing and health education), reduced the incidence of human cases from 2.8 per 100,000 inhabitants in 1981 to less than 0.01 per 100,000 since 1997. The canine infection rates decreased from 4.6% in 1984 to 1.6% in 2008. Lutzomyia longipalpis was not detected in some locations where human and canine cases occurred. In the years 2007 and 2008, no new human cases were reported, but there is a persistent and worrisome residual canine seroprevalence. PMID:19967242

  5. Afferent and Efferent Aspects of Mandibular Sensorimotor Control in Adults who Stutter

    PubMed Central

    Daliri, Ayoub; Prokopenko, Roman A.; Max, Ludo

    2013-01-01

    Purpose Individuals who stutter show sensorimotor deficiencies in speech and nonspeech movements. For the mandibular system, we dissociated the sense of kinesthesia from the efferent control component to examine whether kinesthetic integrity itself is compromised in stuttering or whether deficiencies occur only when generating motor commands. Method We investigated 11 stuttering and 11 nonstuttering adults’ kinesthetic sensitivity threshold and kinesthetic accuracy for passive jaw movements as well as their minimal displacement threshold and positioning accuracy for active jaw movements. We also investigated the correlation with an anatomical index of jaw size. Results The groups showed no statistically significant differences on sensory measures for passive jaw movements. Although some stuttering individuals performed more poorly than any nonstuttering participants on the active movement tasks, between-group differences for active movements were also not statistically significant. Unlike fluent speakers, however, the stuttering group showed a statistically significant correlation between mandibular size and performance in the active and passive near-threshold tasks. Conclusions Previously reported minimal movement differences were not replicated. Instead, stuttering individuals’ performance varied with anatomical properties. These correlational results are consistent with the hypothesis that stuttering participants generate and perceive movements based on less accurate internal models of the involved neuromechanical systems. PMID:23816664

  6. Systems engineering aspects of a preliminary conceptual design of the space station environmental control and life support system

    NASA Technical Reports Server (NTRS)

    Lin, C. H.; Meyer, M. S.

    1983-01-01

    The systems engineering aspects of developing a conceptual design of the Space Station Environmental Control and Life Support System (ECLSS) are discussed. Topics covered include defining system requirements and groundrules for approach, formulating possible cycle closure options, and establishing a system-level mass balance on the essential materials processed in oxygen and water cycles. Consideration is also given to the performance of a system trade-off study to determine the best degree of cycle closure for the ECLSS, and the construction of a conceptual design of the ECLSS with subsystem performance specifications and candidate concepts. For the optimum balance between development costs, technological risks, and resupply penalties, a partially closed cycle ECLSS option is suggested.

  7. Temporal patterns of diversity: Assessing the biotic and abiotic controls on ant assemblages

    USGS Publications Warehouse

    Dunn, R.R.; Parker, C.R.; Sanders, N.J.

    2007-01-01

    In this study, we use 12 months of data from 11 ant assemblages to test whether seasonal variation in ant diversity is governed by either the structuring influences of interspecific competition or environmental conditions. Because the importance of competition might vary along environmental gradients, we also test whether the signature of competition depends on elevation. We find little evidence that competition structures the seasonal patterns of activity in the ant assemblages considered, but find support for the effects of temperature on seasonal patterns of diversity, especially at low-elevation sites. Although, in general, both competition and the environment interact to structure ant assemblages, our results suggest that environmental conditions are the primary force structuring the seasonal activity of the ant assemblages studied here. ?? 2007 The Linnean Society of London.

  8. Modeling Elevation and Aspect Controls on Emerging Ecohydrologic Processes and Ecosystem Patterns Using the Component-based Landlab Framework

    NASA Astrophysics Data System (ADS)

    Nudurupati, S. S.; Istanbulluoglu, E.; Adams, J. M.; Hobley, D. E. J.; Gasparini, N. M.; Tucker, G. E.; Hutton, E. W. H.

    2014-12-01

    Topography plays a commanding role on the organization of ecohydrologic processes and resulting vegetation patterns. In southwestern United States, climate conditions lead to terrain aspect- and elevation-controlled ecosystems, with mesic north-facing and xeric south-facing vegetation types; and changes in biodiversity as a function of elevation from shrublands in low desert elevations, to mixed grass/shrublands in mid elevations, and forests at high elevations and ridge tops. These observed patterns have been attributed to differences in topography-mediated local soil moisture availability, micro-climatology, and life history processes of plants that control chances of plant establishment and survival. While ecohydrologic models represent local vegetation dynamics in sufficient detail up to sub-hourly time scales, plant life history and competition for space and resources has not been adequately represented in models. In this study we develop an ecohydrologic cellular automata model within the Landlab component-based modeling framework. This model couples local vegetation dynamics (biomass production, death) and plant establishment and competition processes for resources and space. This model is used to study the vegetation organization in a semiarid New Mexico catchment where elevation and hillslope aspect play a defining role on plant types. Processes that lead to observed plant types across the landscape are examined by initializing the domain with randomly assigned plant types and systematically changing model parameters that couple plant response with soil moisture dynamics. Climate perturbation experiments are conducted to examine the plant response in space and time. Understanding the inherently transient ecohydrologic systems is critical to improve predictions of climate change impacts on ecosystems.

  9. Resident-invader phylogenetic relatedness, not resident phylogenetic diversity, controls community invasibility.

    PubMed

    Tan, Jiaqi; Pu, Zhichao; Ryberg, Wade A; Jiang, Lin

    2015-07-01

    A central goal of invasion biology is to elucidate mechanisms regulating community invasibility. Darwin's naturalization hypothesis, one of the oldest hypotheses in invasion biology, emphasizes the importance of phylogenetic relatedness (PR) between resident and invader species for predicting invasibility. Alternatively, a recent extension of the diversity-invasibility hypothesis predicts that phylogenetic diversity (PD) of resident communities influences invasibility. Neither of these hypotheses has undergone rigorous experimental testing, and the relative contributions of PR and PD to community invasibility are unknown, in part because their effects tend to be confounded with each other. Here we consider both perspectives together by independently manipulating PR and PD in laboratory bacterial assemblages. We found that, although invader abundance decreased significantly as PR increased, it was unaffected by PD. Likewise, we found that resident-invader functional similarity, not functional diversity of resident communities, was a significant predictor of invader abundance. Nevertheless, invader abundance was better predicted by PR than by functional similarity. These results highlight the importance of considering species evolutionary relationships, especially the PR between resident and invader species, for the prediction, prevention, and management of biological invasions. PMID:26098339

  10. The antimicrobial potential of ionic liquids: A source of chemical diversity for infection and biofilm control.

    PubMed

    Pendleton, Jack Norman; Gilmore, Brendan F

    2015-08-01

    Although described almost a century ago, interest in ionic liquids has flourished in the last two decades, with significant advances in the understanding of their chemical, physical and biological property sets driving their widespread application across multiple and diverse research areas. Significant progress has been made through the contributions of numerous research groups detailing novel libraries of ionic liquids, often 'task-specific' designer solvents for application in areas as diverse as separation technology, catalysis and bioremediation. Basic antimicrobial screening has often been included as a surrogate indication of the environmental impact of these compounds widely regarded as 'green' solvents. Obviating the biological properties, specifically toxicity, of these compounds has obstructed their potential application as sophisticated designer biocides. A recent tangent in ionic liquids research now aims to harness tuneable biological properties of these compounds in the design of novel potent antimicrobials, recognising their unparalleled flexibility for chemical diversity in a severely depleted antimicrobial arsenal. This review concentrates primarily on the antimicrobial potential of ionic liquids and aims to consolidate contemporary microbiological background information, assessment protocols and future considerations necessary to advance the field in light of the urgent need for antimicrobial innovation. PMID:25907139

  11. Pythium species and isolate diversity influence inhibition by the biological control agent Streptomyces lydicus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disease control of soilborne pathogens by biological control agents has often been inconsistent under field conditions. One factor that may contribute to this inconsistency is the variability in response among pathogen populations and/or communities to the selected biological control agent. One hund...

  12. Genetic diversity of marine Synechococcus and co-occurring cyanophage communities: evidence for viral control of phytoplankton.

    PubMed

    Mhling, Martin; Fuller, Nicholas J; Millard, Andrew; Somerfield, Paul J; Marie, Dominique; Wilson, William H; Scanlan, David J; Post, Anton F; Joint, Ian; Mann, Nicholas H

    2005-04-01

    Unicellular cyanobacteria of the genus Synechococcus are a major component of the picophytoplankton and make a substantial contribution to primary productivity in the oceans. Here we provide evidence that supports the hypothesis that virus infection can play an important role in determining the success of different Synechococcus genotypes and hence of seasonal succession. In a study of the oligotrophic Gulf of Aqaba, Red Sea, we show a succession of Synechococcus genotypes over an annual cycle. There were large changes in the genetic diversity of Synechococcus, as determined by restriction fragment length polymorphism analysis of a 403- bp rpoC1 gene fragment, which was reduced to one dominant genotype in July. The abundance of co-occurring cyanophage capable of infecting marine Synechococcus was determined by plaque assays and their genetic diversity was determined by denaturing gradient gel electrophoresis analysis of a 118-bp g20 gene fragment. The results indicate that both abundance and genetic diversity of cyanophage covaried with that of Synechococcus. Multivariate statistical analyses show a significant relationship between cyanophage assemblage structure and that of Synechococcus. These observations are consistent with cyanophage infection being a major controlling factor in picophytoplankton succession. PMID:15816927

  13. Fungal diversity controls the temperature sensitivity of soil organic matter decomposition under drought stress

    NASA Astrophysics Data System (ADS)

    Curiel Yuste, Jorge

    2010-05-01

    Soil respiration, the production, transport and efflux of CO2 in soils, is typically the main source of CO2 in terrestrial ecosystems. Microbial-mediated decomposition of soil organic matter (SOM) ultimately makes a considerable contribution to soil respiration and it is strongly sensitive to climate. Despite the central role of microbes in decomposition of SOM, few studies have been conducted on how microbial community ecology may affect this large CO2 flux. This lack of research rests on the belief that the high degree of functional redundancy in soils compensates for any given change in microbial community composition. Here we show that fungal community was more resilient to 10 years of severe drought than bacterial community and that fungal diversity was the best predictor of the sensitivity of SOM decomposition to temperature (Q10). The results highlight the important role of fungi in decomposition of terrestrial SOM, especially under the harsh environmental conditions of Mediterranean ecosystems, where models predict even drier future conditions. Our results also hold up the hypotheses that diversified communities may make a better use of available resources. Fungal biomass and diversity need therefore to be extensively and intensively explored in order to understand soil CO2 emissions from the different types of ecosystems, especially in the frame of current human-driven alteration of the carbon cycle and the resulting climate change.

  14. The transcription factor Apontic-like controls diverse colouration pattern in caterpillars.

    PubMed

    Yoda, Shinichi; Yamaguchi, Junichi; Mita, Kazuei; Yamamoto, Kimiko; Banno, Yutaka; Ando, Toshiya; Daimon, Takaaki; Fujiwara, Haruhiko

    2014-01-01

    Genetic polymorphisms underlie the convergent and divergent evolution of various phenotypes. Diverse colour patterns on caterpillars, which are ecologically important, are good models for understanding the molecular backgrounds of phenotypic diversity. Here we show that a single evolutionarily conserved gene apontic-like (apt-like) encoding for a putative transcription factor accounts for the silkworm p locus, which causes at least 15 different larval markings involved in branch-like markings and eye-spot formation. The expression of apt-like and melanin synthesis genes are upregulated in association with pigmented areas of marking mutants Striped (p(S)) and normal (+(p)) but not in the non-marking allele plain (p). Functional analyses, ectopic expression, RNAi and TALEN, demonstrate that apt-like causes melanin pigmentation in a cell-autonomous manner. These results suggest that variation in p alleles is caused by the differential expression of the gene apt-like which induces targeted elevation of gene expressions in the melanin synthesis pathway. PMID:25233442

  15. The Mechanical Diversity of Stomata and Its Significance in Gas-Exchange Control[OA

    PubMed Central

    Franks, Peter J.; Farquhar, Graham D.

    2007-01-01

    Given that stomatal movement is ultimately a mechanical process and that stomata are morphologically and mechanically diverse, we explored the influence of stomatal mechanical diversity on leaf gas exchange and considered some of the constraints. Mechanical measurements were conducted on the guard cells of four different species exhibiting different stomatal morphologies, including three variants on the classical kidney form and one dumb-bell type; this information, together with gas-exchange measurements, was used to model and compare their respective operational characteristics. Based on evidence from scanning electron microscope images of cryo-sectioned leaves that were sampled under full sun and high humidity and from pressure probe measurements of the stomatal aperture versus guard cell turgor relationship at maximum and zero epidermal turgor, it was concluded that maximum stomatal apertures (and maximum leaf diffusive conductance) could not be obtained in at least one of the species (the grass Triticum aestivum) without a substantial reduction in subsidiary cell osmotic (and hence turgor) pressure during stomatal opening to overcome the large mechanical advantage of subsidiary cells. A mechanism for this is proposed, with a corollary being greatly accelerated stomatal opening and closure. Gas-exchange measurements on T. aestivum revealed the capability of very rapid stomatal movements, which may be explained by the unique morphology and mechanics of its dumb-bell-shaped stomata coupled with see-sawing of osmotic and turgor pressure between guard and subsidiary cells during stomatal opening or closure. Such properties might underlie the success of grasses. PMID:17114276

  16. Benthic control freaks: Effects of the tubiculous amphipod Haploops nirae on the specific diversity and functional structure of benthic communities

    NASA Astrophysics Data System (ADS)

    Rigolet, Carinne; Dubois, Stanislas F.; Thibaut, Eric

    2014-01-01

    Haploops nirae is a gregarious tubiculous amphipod which extended its habitat over thousands of hectares in shallow waters of South Brittany bays (Bay of Biscay, Atlantic) over the last decades and created uniquely large and dense tube mats. In the bay of Concarneau, we investigated the specific diversity (i.e. species richness and species composition) and the functional structure (using biological traits) of the macrofauna associated with this Haploops community as a comparison with several surrounding soft-sediment communities to determine the effect of this engineer species on ecosystem functions. We showed that the occurrence of Haploops tubes and individuals significantly modifies sediment features (e.g. change in sediment grain size, increase in C and N organic content) but also largely affect species diversity and benthic composition. The species richness was significantly higher in Haploops community but the species assemblage associated with Haploops habitat was very homogeneous compared to the neighboring habitats and unique with 33% of all species exclusively found in this community. Multivariate analysis (dbRDA) revealed that Haploops density was by far the factor explaining the variation in species composition of benthic communities. No differences in species diversity and assemblage were detected in relationship to Haploops density. A biological trait analysis performed on the whole ecosystem (Haploops included) revealed that Haploops largely dominates the functional structure of the Haploops community by its own functional traits. When performed on selected traits of the associated fauna only (Haploops excluded) the functional structure of the Haploops community was characterized by a greatly reduced proportion of small to medium long lived, sensitive to disturbance, free living or burrowing/tube-building filter-feeding species. H. nirae appears to be a bioengineer and a foundation species that largely modifies its hydro-sedimentary features, controlling diversity and abundances of associated species, and creating a complex set of positive and negative interactions so that a unique benthic assemblage is found in sediments they colonized.

  17. Practical and analytic aspects of using friend controls in case-control studies: experience from a case-control study of childhood cancer

    PubMed Central

    Bunin, Greta R; Vardhanabhuti, Saran; Lin, Agueda; Anschuetz, Greta L; Mitra, Nandita

    2012-01-01

    Summary The authors report empirical data on the use of friend controls, specifically response rates, case-control concordance, and analytic approaches. The data derive from a North American multi-institutional study of childhood cancer that was conducted in 20022007 and that focused on paternal exposures. Case parents nominated friends as potential controls; up to 3 controls participated per case. For 137 (69%) of the 199 case families, at least 1 control participated. Of 374 potential controls contacted, 247 (66%) participated. Case fathers with controls were markedly more likely to be non-Hispanic white, college graduates, and non-smokers compared to case fathers without controls. Odds ratios adjusted for demographic characteristics were generally similar but occasionally differed between analyses that included only members of matched sets and those that included all participants, i.e. controls and cases with and without controls. For demographic characteristics, simulations demonstrated that the observed concordance of cases and controls within matched sets exceeded that expected under random ascertainment, indicating probable overmatching. However, the observed concordance of smoking and other exposures was similar to the expectation under random ascertainment suggesting little overmatching on exposures. Although not ideal, friend controls were convenient, had a reasonably high response rate, and provided controls closely matched on race/ethnicity, education, and age. PMID:21819422

  18. Arabidopsis Ovate Family Proteins, a Novel Transcriptional Repressor Family, Control Multiple Aspects of Plant Growth and Development

    SciTech Connect

    Wang, Shucai; Chang, Ying; Guo, Jianjun; Zeng, Qingning; Ellis, Brian; Chen, Jay

    2011-01-01

    BACKGROUND: The Arabidopsis genome contains 18 genes that are predicted to encode Ovate Family Proteins (AtOFPs), a protein family characterized by a conserved OVATE domain, an approximately 70-amino acid domain that was originally found in tomato OVATE protein. Among AtOFP family members, AtOFP1 has been shown to suppress cell elongation, in part, by suppressing the expression of AtGA20ox1, AtOFP4 has been shown to regulate secondary cell wall formation by interact with KNOTTED1-LIKE HOMEODOMAIN PROTEIN 7 (KNAT7), and AtOFP5 has been shown to regulate the activity of a BEL1-LIKEHOMEODOMAIN 1(BLH1)-KNAT3 complex during early embryo sac development, but little is known about the function of other AtOFPs. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrated here that AtOFP proteins could function as effective transcriptional repressors in the Arabidopsis protoplast transient expression system. The analysis of loss-of-function alleles of AtOFPs suggested AtOFP genes may have overlapping function in regulating plant growth and development, because none of the single mutants identified, including T-DNA insertion mutants in AtOFP1, AtOFP4, AtOFP8, AtOFP10, AtOFP15 and AtOFP16, displayed any apparent morphological defects. Further, Atofp1 Atofp4 and Atofp15 Atofp16 double mutants still did not differ significantly from wild-type. On the other hand, plants overexpressing AtOFP genes displayed a number of abnormal phenotypes, which could be categorized into three distinct classes, suggesting that AtOFP genes may also have diverse functions in regulating plant growth and development. Further analysis suggested that AtOFP1 regulates cotyledon development in a postembryonic manner, and global transcript profiling revealed that it suppress the expression of many other genes. CONCLUSIONS/SIGNIFICANCE: Our results showed that AtOFPs function as transcriptional repressors and they regulate multiple aspects of plant growth and development. These results provided the first overview of a previously unknown transcriptional repressor family, and revealed their possible roles in plant growth and development.

  19. Diverse lamin-dependent mechanisms interact to control chromatin dynamics. Focus on laminopathies.

    PubMed

    Camozzi, Daria; Capanni, Cristina; Cenni, Vittoria; Mattioli, Elisabetta; Columbaro, Marta; Squarzoni, Stefano; Lattanzi, Giovanna

    2014-01-01

    Interconnected functional strategies govern chromatin dynamics in eukaryotic cells. In this context, A and B type lamins, the nuclear intermediate filaments, act on diverse platforms involved in tissue homeostasis. On the nuclear side, lamins elicit large scale or fine chromatin conformational changes, affect DNA damage response factors and transcription factor shuttling. On the cytoplasmic side, bridging-molecules, the LINC complex, associate with lamins to coordinate chromatin dynamics with cytoskeleton and extra-cellular signals. Consistent with such a fine tuning, lamin mutations and/or defects in their expression or post-translational processing, as well as mutations in lamin partner genes, cause a heterogeneous group of diseases known as laminopathies. They include muscular dystrophies, cardiomyopathy, lipodystrophies, neuropathies, and progeroid syndromes. The study of chromatin dynamics under pathological conditions, which is summarized in this review, is shedding light on the complex and fascinating role of the nuclear lamina in chromatin regulation. PMID:25482195

  20. Diverse sensitivity of RHA/Verh and RLA/Verh rats to emotional and spatial aspects of a novel environment as a result of a distinct pattern of neuronal activation in the fear/anxiety circuit.

    PubMed

    Meyza, Ksenia Z; Boguszewski, Pawel M; Nikolaev, Evgeni; Zagrodzka, Jolanta

    2009-01-01

    Psychogenetically selected Roman high (RHA/Verh) and Roman low (RLA/Verh) avoidance rats constitute a well-recognized model of diverse emotional reactivity. The two Swiss lines display marked behavioral and endocrine differences in reaction to a novel environment. In our study we found that these differences are accompanied by a distinct, line-specific pattern of neuronal activation within the fear/anxiety circuit. We have compared the c-Fos protein expression in the medial prefrontal cortex (mPFC), basolateral (BLA), central (CeA), medial (MeA), and cortical (CoA) nuclei of amygdala, paraventricular nucleus of the hypothalamus (PVN), and CA1, CA2, and CA3 fields of the hippocampus upon exposure to a novel situation of different stressorgeneity (open field with illuminated center, elevated plus maze, hole board test and acute restraint). Profound between-line differences in the sensitivity to emotional and spatial aspects of the behavioral challenge were observed for tests measuring spontaneous behavior. This effect seems to reflect different motivational factors driving the rat behavior, which clearly suggests that the diverse emotional reactivity of RHA/Verh and RLA/Verh rats is a result of different activation of the fear/anxiety circuit. PMID:18972198

  1. Masking foods for food challenge: practical aspects of masking foods for a double-blind, placebo-controlled food challenge.

    PubMed

    Huijbers, G B; Colen, A A; Jansen, J J; Kardinaal, A F; Vlieg-Boerstra, B J; Martens, B P

    1994-06-01

    In diagnosing a food allergy or food intolerance, a double-blind, placebo-controlled food challenge (DBPCFC) with the suspected food or food substance is the only method available for objective confirmation of an assumed relationship between a suspected agent and a complaint. When the use of capsules as a vehicle for DBPCFC with the suspected agent is not feasible, recipes have to be developed for masking the suspected food with another food. We describe demands and other aspects of the development of recipes for DBPCFC purposes. The taste, smell, color, and texture of the suspected agent have to be hidden in such a way that the patient cannot tell which of the two foods (the active food or the placebo food) contains the suspected agent. Once developed, the recipes have to be judged carefully to ensure that the foods do not contain ingredients other than the suspected agent that can possibly provoke complaints in the patient. Besides ordinary equipment such as cutlery, glasses, and dishes, the minimal equipment needed for preparing the recipes is an accurate balance. The more laborious a recipe is to make, the more equipment is needed. The development of recipes and the preparation of masked foods are time-consuming, which makes DBPCFC with masked foods difficult to perform in daily clinical practice. Performing a DBPCFC with masked foods in daily clinical practice can be a great challenge to the imagination and creativity of a dietitian. PMID:8195554

  2. Novel aspect in grain size control of nanocrystalline diamond film for thin film waveguide mode resonance sensor application.

    PubMed

    Lee, Hak-Joo; Lee, Kyeong-Seok; Cho, Jung-Min; Lee, Taek-Sung; Kim, Inho; Jeong, Doo Seok; Lee, Wook-Seong

    2013-11-27

    Nanocrystalline diamond (NCD) thin film growth was systematically investigated for application for the thin film waveguide mode resonance sensor. The NCD thin film was grown on the Si wafer or on the SiO2-coated sapphire substrate using the hot filament chemical vapor deposition (HFCVD). The structural/optical properties of the samples were characterized by the high-resolution scanning electron microscopy (HRSEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDS), near edge X-ray absorption fine structure (NEXAFS), X-ray diffraction (XRD), and ultraviolet-visible (UV-vis) spectroscopy. The waveguide modes of the NCD layer were studied by prism coupler technique using laser (wavelength: 632.8 nm) with varying incident angle. A novel aspect was disclosed in the grain size dependence on the growth temperature at the relatively low methane concentration in the precursor gas, which was important for optical property: the grain size increased with decreasing growth temperature, which was contrary to the conventional knowledge prevailing in the microcrystalline diamond (MCD) domain. We have provided discussions to reconcile such observation. An optical waveguide mode resonance was demonstrated in the visible region using the microstructure-controlled transparent NCD thin film waveguide, which provided a strong potential for the waveguide mode resonance sensor applications. PMID:24195713

  3. Aspects of Oral Language, Speech, and Written Language in Subjects with Temporal Lobe Epilepsy of Difficult Control

    PubMed Central

    Berberian, Ana Paula; Hopker, Christiane; Mazzarotto, Ingrid; Cunha, Jenane; Guarinello, Ana Cristina; Massi, Giselle; Crippa, Ana

    2015-01-01

    Introduction About 50 million people have epilepsy and 30% of them have epilepsy that does not respond to properly conducted drug treatment. Objective Verify the incidence of language disorders in oral language, speech, and written language of subjects with difficult to control temporal lobe epilepsy (TLE) and compare the occurrence of these disorders in subjects before and after surgery. Methods Cross-sectional study with quantitative analysis, exploratory type. A questionnaire for data collection was administered covering the following aspects: oral language, speech complaints, and writing production and comprehension. Criteria for inclusion of subjects were a diagnosis of TLE refractory to drug treatment and at least 4 years of schooling. Results The sample of 63 patients with TLE was divided into two groups: presurgical (n = 31) and postsurgical (n = 32). In the postsurgical group, there was a higher frequency of left lobectomy (75%) than right (25%). Conclusion Statistical analysis was performed with the chi-square test (significance level of 0.05). Complaints related to speech-language attention were more predominant in postsurgical subjects. Analysis of oral language, speech, and written language in subjects with epilepsy who underwent temporal lobectomy or not showed findings consistent with symptoms related to transient aphasia, with the presence of paraphasias, as well as changes in speech prosody and melody. These symptoms appeared more associated with recurrence after having a temporal lobectomy. PMID:26491475

  4. Human factors aspects of the major upgrade to control systems at the Los Alamos National Laboratory Plutonium Facility

    SciTech Connect

    Higgins, J.; Pope, N.

    1997-06-01

    The Plutonium Facility (TA-55) at Los Alamos National Laboratory (LANL) has been in operation for over 15 years. It handles projects such as: stockpile maintenance, surveillance, and dismantlement; pit rebuild; plutonium power source fabrication for long duration spacecraft missions (e.g., Cassini); nuclear materials technology research; nuclear materials storage; and remediation of nuclear waste. The Operations Center of TA-55 is the nerve center of the facility where operators are on duty around the clock and monitor several thousand data points using the Facility Control System (FCS). The FCS monitors, displays, alarms, and provides some limited control of the following systems; HVAC, fire detection and suppression, radiation detection, electrical, and other miscellaneous systems. The FCS was originally based on late 1970s digital technology, which is not longer supported by the vendors. Additionally, the equipment failure rates increased notably in the 1990s. Thus, plans were put into place to upgrade and replace the FCS hardware, software, and display components with modernized equipment. The process was complicated by the facts that: the facility was operational and could not be totally closed for the modifications; complete documentation was not available for the existing system; the Safety Analyses for the facility were in the process of being upgraded at the same time; and of course limited time and budgets. This paper will discuss the human factors aspects of the design, installation, and testing of the new FCS within the above noted constraints. Particular items to be discussed include the functional requirements definition, operating experience review, screen designs, test program, operator training, and phased activation of the new circuits in an operational facility.

  5. Genetic control of morphometric diversity in the maize shoot apical meristem

    PubMed Central

    Leiboff, Samuel; Li, Xianran; Hu, Heng-Cheng; Todt, Natalie; Yang, Jinliang; Li, Xiao; Yu, Xiaoqing; Muehlbauer, Gary J.; Timmermans, Marja C. P.; Yu, Jianming; Schnable, Patrick S.; Scanlon, Michael J.

    2015-01-01

    The maize shoot apical meristem (SAM) comprises a small pool of stem cells that generate all above-ground organs. Although mutational studies have identified genetic networks regulating SAM function, little is known about SAM morphological variation in natural populations. Here we report the use of high-throughput image processing to capture rich SAM size variation within a diverse maize inbred panel. We demonstrate correlations between seedling SAM size and agronomically important adult traits such as flowering time, stem size and leaf node number. Combining SAM phenotypes with 1.2 million single nucleotide polymorphisms (SNPs) via genome-wide association study reveals unexpected SAM morphology candidate genes. Analyses of candidate genes implicated in hormone transport, cell division and cell size confirm correlations between SAM morphology and trait-associated SNP alleles. Our data illustrate that the microscopic seedling SAM is predictive of adult phenotypes and that SAM morphometric variation is associated with genes not previously predicted to regulate SAM size. PMID:26584889

  6. Non-cell-autonomous control of denticle diversity in the Drosophila embryo

    PubMed Central

    Dilks, Stacie A.; DiNardo, Stephen

    2010-01-01

    Certain Drosophila embryonic epidermal cells construct actin-based protrusions, called denticles, which exhibit stereotyped, column-specific differences in size, density and hook orientation. This precise denticle pattern is conserved throughout all drosophilids yet studied, and screening for mutations that affect this pattern has been used to identify genes involved in development and signaling. However, how column-specific differences are specified and the mechanism(s) involved have remained elusive. Here, we show that the transcription factor Stripe is required for multiple aspects of this column-specific denticle pattern, including denticle hook orientation. The induction of stripe expression in certain denticle field cells appears to be the primary mechanism by which developmental pathways assign denticle hook orientation. Furthermore, we show that the cytoskeletal linker protein Short stop (Shot) functions both cell-autonomously and non-autonomously to specify denticle hook orientation via interaction with the microtubule cytoskeleton. We propose that stripe mediates its effect on hook orientation, in part, via upregulation of shot. PMID:20332154

  7. Genetic diversity studies of Brazilian garlic cultivars and quality control of garlic-clover production.

    PubMed

    Buso, G S C; Paiva, M R; Torres, A C; Resende, F V; Ferreira, M A; Buso, J A; Dusi, A N

    2008-01-01

    The garlic cultivars grown in Brazil evolved from somatic mutations and clone selection by breeding programs and by the introduction of germplasm from other countries. Morphological characters have been used to differentiate these cultivars. Two hundred and six random amplified polymorphic DNA markers were utilized for a diversity analysis of the 17 most planted garlic cultivars in Brazil. Bootstrap analysis showed that the number of markers was efficient and sufficient to obtain a coefficient of variation of 10%. Similarity varied between 16 and 98% and cluster analysis showed that, in general, genetic similarities correlate with morphological characters of the cultivars and production cycle variation. High bootstrap values at most of the nodes supported the dendrogram stability. The grouping of most varieties agreed well with previous reports based on morphological characters. As a vegetative-propagated species, viral diseases are a key problem regarding production and quality of the bulbs, causing gradual loss of yield and decrease in storage capacity. To improve the health quality of garlic seed, a virus-free stock of garlic cloves of the Amarante cultivar was obtained. The ability to distinguish garlic cultivars to detect varietal mixing after in vitro multiplication is extremely important, since correct identification is not possible until bulbs are produced. Random amplified polymorphic DNA markers were also used to differentiate cultivars while they are in vitro and not amenable to morphological discrimination. No difference was identified between the fingerprints of the virus-free or of the infected bulks of Amarante, showing that there was no clove mixing in the handling of material in the clonal multiplication phase. PMID:18752178

  8. Genetic diversity of Aphthona flea beetles introduced into North America for biological control of leafy spurge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Five species of Aphthona flea beetles from Europe (Aphthona flava, Aphthona cyparissiae, Aphthona nigriscutis, Aphthona czwalinae, and Aphthona lacertosa) have been introduced and become established in North America for the purpose of controlling the noxious weed, leafy spurge. Within species gene...

  9. Important helminth infections in Southeast Asia diversity, potential for control and prospects for elimination.

    PubMed

    Utzinger, Jürg; Bergquist, Robert; Olveda, Remigio; Zhou, Xiao-Nong

    2010-01-01

    Besides the 'big three'-HIV/AIDS, malaria and tuberculosis-there are a host of diseases that, by comparison, are truly neglected. These so-called neglected tropical diseases (NTDs), many of which caused by helminths, are intimately linked with poverty and are rampant where housing is poor; access to clean water and adequate sanitation is lacking; hygiene and nutrition is substandard and populations are marginalized and vulnerable. More than a billion people are affected by NTDs, mainly in remote rural and deprived urban settings of the developing world. An overview of papers published in two special thematic volumes of the Advances in Parasitology is provided here under the umbrella of current status of research and control of important helminth infections. A total of 25 comprehensive reviews are presented, which summarise the latest available data pertaining to the diagnosis, epidemiology, pathogenesis, prevention, treatment, control and eventual elimination of NTDs in Southeast Asia and neighbourhood countries. The focus of the first volume provides the current regional status of schistosomiasis, lymphatic filariasis, food-borne trematodiases, echinococcosis and cysticercosis/taeniasis, less common parasitic diseases that can cause epidemic outbreaks and helminth infections affecting the central nervous system. The second volume deals with the tools and strategies for control, including diagnostics, drugs, vaccines and cutting-edge basic research (e.g. the '-omics' sciences). Moreover, cross-cutting themes such as multiparasitism, social sciences, capacity strengthening, geospatial health technologies, health metrics and modelling the potential impact of climate change on helminthic diseases are discussed. Hopefully, these two volumes will become useful for researchers and, most importantly, disease control managers for integrated and sustainable control, rigorous monitoring and eventual elimination of NTDs in Southeast Asia and elsewhere. PMID:20624526

  10. Decreased functional diversity and biological pest control in conventional compared to organic crop fields.

    PubMed

    Krauss, Jochen; Gallenberger, Iris; Steffan-Dewenter, Ingolf

    2011-01-01

    Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional) and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short-term effects on aphid densities but long-term negative effects on biological pest control. Therefore conventional farmers should restrict insecticide applications to situations where thresholds for pest densities are reached. PMID:21611171

  11. Decreased Functional Diversity and Biological Pest Control in Conventional Compared to Organic Crop Fields

    PubMed Central

    Krauss, Jochen; Gallenberger, Iris; Steffan-Dewenter, Ingolf

    2011-01-01

    Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional) and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short-term effects on aphid densities but long-term negative effects on biological pest control. Therefore conventional farmers should restrict insecticide applications to situations where thresholds for pest densities are reached. PMID:21611171

  12. Diverse Thinking about Diversity

    ERIC Educational Resources Information Center

    Kaplan, Sandra N.

    2013-01-01

    This article focuses on the concept of diversity in educational decision making. It is noted that the differences that distinguish the needs, interests and abilities are identified by educators. It lists misconceptions resulting from not attending to within-group diversity, and states that a "loss of self" for individual members of

  13. Enhancer Diversity and the Control of a Simple Pattern of Drosophila CNS Midline Cell Expression

    PubMed Central

    Pearson, Joseph C.; Crews, Stephen T.

    2014-01-01

    Transcriptional enhancers integrate information derived from transcription factor binding to control gene expression. One key question concerns the extent of trans- and cis-regulatory variation in how co-expressed genes are controlled. The Drosophila CNS midline cells constitute a group of neurons and glia in which expression changes can be readily characterized during specification and differentiation. Using a transgenic approach, we compare the cis-regulation of multiple genes expressed in the Drosophila CNS midline primordium cells, and show that while the expression patterns may appear alike, the target genes are not equivalent in how these common expression patterns are achieved. Some genes utilize a single enhancer that promotes expression in all midline cells, while others utilize multiple enhancers with distinct spatial, temporal, and quantitative contributions. Two regulators, Single-minded and Notch, play key roles in controlling early midline gene expression. While Single-minded is expected to control expression of most, if not all, midline primordium-expressed genes, the role of Notch in directly controlling midline transcription is unknown. Midline primordium expression of the rhomboid gene is dependent on cell signaling by the Notch signaling pathway. Mutational analysis of a rhomboid enhancer reveals at least 5 distinct types of functional cis-control elements, including a binding site for the Notch effector, Suppressor of Hairless. The results suggest a model in which Notch/Suppressor of Hairless levels are insufficient to activate rhomboid expression by itself, but does so in conjunction with additional factors, some of which, including Single-minded, provide midline specificity to Notch activation. Similarly, a midline glial enhancer from the argos gene, which is dependent on EGF/Spitz signaling, is directly regulated by contributions from both Pointed, the EGF transcriptional effector, and Single-minded. In contrast, midline primordium expression of other genes shows a strong dependence on Single-minded and varying combinations of additional transcription factors. Thus, Single-minded directly regulates midline primordium-expressed genes, but in some cases plays a primary role in directing target gene midline expression, and in others provides midline specificity to cell signaling inputs. PMID:24854999

  14. Emergency Victim Care. A Training Manual for Emergency Medical Technicians. Module 2. Equipment, Safe Driving Practices, Legal Aspects, Controlling the Situation, Action Evaluation Conference. Revised.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Div. of Vocational Education.

    This student manual, the second in a set of 14 modules, is designed to train emergency medical technicians (EMTs) in Ohio. The module contains five sections that cover the following course content: ambulance equipment, safe driving practices for emergency vehicle drivers, legal aspects of the EMT's job, how to maintain control at an accident scene

  15. Emergency Victim Care. A Training Manual for Emergency Medical Technicians. Module 2. Equipment, Safe Driving Practices, Legal Aspects, Controlling the Situation, Action Evaluation Conference. Revised.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Div. of Vocational Education.

    This student manual, the second in a set of 14 modules, is designed to train emergency medical technicians (EMTs) in Ohio. The module contains five sections that cover the following course content: ambulance equipment, safe driving practices for emergency vehicle drivers, legal aspects of the EMT's job, how to maintain control at an accident scene…

  16. A facile phosphine-free colloidal synthesis of Cu2SnS3 and Cu2ZnSnS4 nanorods with a controllable aspect ratio.

    PubMed

    Wang, Jian-Jun; Liu, Pai; Ryan, Kevin M

    2015-09-18

    Cu2SnS3 (CTS) nanorods were synthesized with a controllable aspect ratio via a facile phosphine-free colloidal synthesis. This synthesis can be readily extended to obtain Cu2ZnSnS4 (CZTS) nanorods with tunable Zn content. PMID:26235602

  17. Merging metagenomics and geochemistry reveals environmental controls on biological diversity and evolution

    PubMed Central

    2014-01-01

    Background The metabolic strategies employed by microbes inhabiting natural systems are, in large part, dictated by the physical and geochemical properties of the environment. This study sheds light onto the complex relationship between biology and environmental geochemistry using forty-three metagenomes collected from geochemically diverse and globally distributed natural systems. It is widely hypothesized that many uncommonly measured geochemical parameters affect community dynamics and this study leverages the development and application of multidimensional biogeochemical metrics to study correlations between geochemistry and microbial ecology. Analysis techniques such as a Markov cluster-based measure of the evolutionary distance between whole communities and a principal component analysis (PCA) of the geochemical gradients between environments allows for the determination of correlations between microbial community dynamics and environmental geochemistry and provides insight into which geochemical parameters most strongly influence microbial biodiversity. Results By progressively building from samples taken along well defined geochemical gradients to samples widely dispersed in geochemical space this study reveals strong links between the extent of taxonomic and functional diversification of resident communities and environmental geochemistry and reveals temperature and pH as the primary factors that have shaped the evolution of these communities. Moreover, the inclusion of extensive geochemical data into analyses reveals new links between geochemical parameters (e.g. oxygen and trace element availability) and the distribution and taxonomic diversification of communities at the functional level. Further, an overall geochemical gradient (from multivariate analyses) between natural systems provides one of the most complete predictions of microbial taxonomic and functional composition. Conclusions Clustering based on the frequency in which orthologous proteins occur among metagenomes facilitated accurate prediction of the ordering of community functional composition along geochemical gradients, despite a lack of geochemical input. The consistency in the results obtained from the application of Markov clustering and multivariate methods to distinct natural systems underscore their utility in predicting the functional potential of microbial communities within a natural system based on system geochemistry alone, allowing geochemical measurements to be used to predict purely biological metrics such as microbial community composition and metabolism. PMID:24886397

  18. Transonic steady- and unsteady-pressure measurements on a high-aspect-ratio supercritical-wing model with oscillating control surfaces

    NASA Technical Reports Server (NTRS)

    Sandford, M. C.; Ricketts, R. H.; Cazier, F. W., Jr.

    1980-01-01

    A supercritical wing with an aspect ratio of 10.76 and with two trailing-edge oscillating control surfaces is described. The semispan wing is instrumented with 252 static orifices and 164 in situ dynamic-pressure gages for studying the effects of control-surface position and motion on steady- and unsteady-pressures at transonic speeds. Results from initial tests conducted in the Langley Transonic Dynamics Tunnel at two Reynolds numbers are presented in tabular form.

  19. Molecular aspects of transport in thin films of controlled architecture. [Annual] technical summary, July 1, 1992--June 30, 1993

    SciTech Connect

    Not Available

    1993-12-01

    Work has progressed in two principal areas during the past year: diffusion in swollen polymer films with and without a barrier layer, and molecular aspects of swelling using enhanced Raman spectroscopy.

  20. Molecular aspects of transport in thin films of controlled architecture. Technical summary, July 1, 1991--June 30, 1992

    SciTech Connect

    Not Available

    1992-12-01

    Work was done in two principal areas: characterization of diffusion in swollen polymer films both with and without a barrier layer, and initial investigations of molecular aspects of swelling using enhanced Raman spectroscopy.

  1. Integration of Signals along Orthogonal Axes of the Vertebrate Neural Tube Controls Progenitor Competence and Increases Cell Diversity

    PubMed Central

    Sasai, Noriaki; Kutejova, Eva; Briscoe, James

    2014-01-01

    A relatively small number of signals are responsible for the variety and pattern of cell types generated in developing embryos. In part this is achieved by exploiting differences in the concentration or duration of signaling to increase cellular diversity. In addition, however, changes in cellular competence—temporal shifts in the response of cells to a signal—contribute to the array of cell types generated. Here we investigate how these two mechanisms are combined in the vertebrate neural tube to increase the range of cell types and deliver spatial control over their location. We provide evidence that FGF signaling emanating from the posterior of the embryo controls a change in competence of neural progenitors to Shh and BMP, the two morphogens that are responsible for patterning the ventral and dorsal regions of the neural tube, respectively. Newly generated neural progenitors are exposed to FGF signaling, and this maintains the expression of the Nk1-class transcription factor Nkx1.2. Ventrally, this acts in combination with the Shh-induced transcription factor FoxA2 to specify floor plate cells and dorsally in combination with BMP signaling to induce neural crest cells. As development progresses, the intersection of FGF with BMP and Shh signals is interrupted by axis elongation, resulting in the loss of Nkx1.2 expression and allowing the induction of ventral and dorsal interneuron progenitors by Shh and BMP signaling to supervene. Hence a similar mechanism increases cell type diversity at both dorsal and ventral poles of the neural tube. Together these data reveal that tissue morphogenesis produces changes in the coincidence of signals acting along orthogonal axes of the neural tube and this is used to define spatial and temporal transitions in the competence of cells to interpret morphogen signaling. PMID:25026549

  2. Controllable Chemoselectivity in Visible-Light Photoredox Catalysis: Four Diverse Aerobic Radical Cascade Reactions.

    PubMed

    Liu, Xinfei; Ye, Xinyi; Bure, Filip; Liu, Hongjun; Jiang, Zhiyong

    2015-09-21

    Reported is the controllable selectivity syntheses of four distinct products from the same starting materials by visible-light photoredox catalysis. By employing a dicyanopyrazine-derived chromophore (DPZ) as photoredox catalyst, an aerobic radical mechanism has been developed, and allows the reactions of N-tetrahydroisoquinolines (THIQs) with N-itaconimides to through four different pathways, including addition-cyclization, addition-elimination, addition-coupling, and addition-protonation, with satisfactory chemoselectivity. The current strategy provide straightforward access to four different but valuable N-heterocyclic adducts in moderate to excellent yields. PMID:26212794

  3. Regulated Control of the Assembly and Diversity of LPS by Noncoding sRNAs

    PubMed Central

    Klein, Gracjana; Raina, Satish

    2015-01-01

    The outer membrane (OM) of Gram-negative bacteria is asymmetric due to the presence of lipopolysaccharide (LPS) facing the outer leaflet of the OM and phospholipids facing the periplasmic side. LPS is essential for bacterial viability, since it provides a permeability barrier and is a major virulence determinant in pathogenic bacteria. In Escherichia coli, several steps of LPS biosynthesis and assembly are regulated by the RpoE sigma factor and stress responsive two-component systems as well as dedicated small RNAs. LPS composition is highly heterogeneous and dynamically altered upon stress and other challenges in the environment because of the transcriptional activation of RpoE regulon members and posttranslational control by RpoE-regulated Hfq-dependent RybB and MicA sRNAs. The PhoP/Q two-component system further regulates Kdo2-lipid A modification via MgrR sRNA. Some of these structural alterations are critical for antibiotic resistance, OM integrity, virulence, survival in host, and adaptation to specific environmental niches. The heterogeneity arises following the incorporation of nonstoichiometric modifications in the lipid A part and alterations in the composition of inner and outer core of LPS. The biosynthesis of LPS and phospholipids is tightly coupled. This requires the availability of metabolic precursors, whose accumulation is controlled by sRNAs like SlrA, GlmZ, and GlmY. PMID:26618164

  4. Diverse ways of perturbing the human arachidonic acid metabolic network to control inflammation.

    PubMed

    Meng, Hu; Liu, Ying; Lai, Luhua

    2015-08-18

    Inflammation and other common disorders including diabetes, cardiovascular disease, and cancer are often the result of several molecular abnormalities and are not likely to be resolved by a traditional single-target drug discovery approach. Though inflammation is a normal bodily reaction, uncontrolled and misdirected inflammation can cause inflammatory diseases such as rheumatoid arthritis and asthma. Nonsteroidal anti-inflammatory drugs including aspirin, ibuprofen, naproxen, or celecoxib are commonly used to relieve aches and pains, but often these drugs have undesirable and sometimes even fatal side effects. To facilitate safer and more effective anti-inflammatory drug discovery, a balanced treatment strategy should be developed at the biological network level. In this Account, we focus on our recent progress in modeling the inflammation-related arachidonic acid (AA) metabolic network and subsequent multiple drug design. We first constructed a mathematical model of inflammation based on experimental data and then applied the model to simulate the effects of commonly used anti-inflammatory drugs. Our results indicated that the model correctly reproduced the established bleeding and cardiovascular side effects. Multitarget optimal intervention (MTOI), a Monte Carlo simulated annealing based computational scheme, was then developed to identify key targets and optimal solutions for controlling inflammation. A number of optimal multitarget strategies were discovered that were both effective and safe and had minimal associated side effects. Experimental studies were performed to evaluate these multitarget control solutions further using different combinations of inhibitors to perturb the network. Consequently, simultaneous control of cyclooxygenase-1 and -2 and leukotriene A4 hydrolase, as well as 5-lipoxygenase and prostaglandin E2 synthase were found to be among the best solutions. A single compound that can bind multiple targets presents advantages including low risk of drug-drug interactions and robustness regarding concentration fluctuations. Thus, we developed strategies for multiple-target drug design and successfully discovered several series of multiple-target inhibitors. Optimal solutions for a disease network often involve mild but simultaneous interventions of multiple targets, which is in accord with the philosophy of traditional Chinese medicine (TCM). To this end, our AA network model can aptly explain TCM anti-inflammatory herbs and formulas at the molecular level. We also aimed to identify activators for several enzymes that appeared to have increased activity based on MTOI outcomes. Strategies were then developed to predict potential allosteric sites and to discover enzyme activators based on our hypothesis that combined treatment with the projected activators and inhibitors could balance different AA network pathways, control inflammation, and reduce associated adverse effects. Our work demonstrates that the integration of network modeling and drug discovery can provide novel solutions for disease control, which also calls for new developments in drug design concepts and methodologies. With the rapid accumulation of quantitative data and knowledge of the molecular networks of disease, we can expect an increase in the development and use of quantitative disease models to facilitate efficient and safe drug discovery. PMID:26237215

  5. Perception and Sense of Control Over Eating Behaviors Among a Diverse Sample of Adults at Risk for Type 2 Diabetes

    PubMed Central

    Fukuoka, Yoshimi; Lindgren, Teri G.; Bonnet, Kemberlee; Kamitani, Emiko

    2014-01-01

    Purpose The purpose of the study was to explore and understand knowledge and attitudes about food, diet, and weight control, focusing on barriers and motivators to reduce risk of developing type 2 diabetes. Methods Six focus groups were conducted in May and June 2010. The groups were stratified by sex. A total of 35 ethnically diverse samples with a high risk for type 2 diabetes participated. The average age was 51 10.6 years, and 57% of the sample represented women. Results Four themes emerged from the focus groups: (1) demonstrated knowledge and source of knowledge, including participants basic understanding of good and bad food and what constitutes a healthy diet and trusted sources of information; (2) perceptions of food and diet, encompassing how participants expressed their perception of and interaction with food and diet; (3) sense of control over dietary intake, reflecting participants discussion of their perceived ability to control their eating patterns and food choices; and (4) eating behaviors, describing participants patterns of eating and perceived barriers to eating a healthy diet. Conclusions Study findings demonstrate that eating healthy requires a complex interaction between individual perceptions of food and sense of control over eating patterns and socio-political and economic structural factors that restrict healthy eating options while promoting unhealthy ones. Programs for long-term eating behavioral change necessary to reduce type 2 diabetes and obesity need to incorporate strategies that address individual-level factors of perception of food and sense of control over eating patterns, as well as structural level factors such as poverty and food insecurity. PMID:24525569

  6. Wildfire, thermokarst and vegetation change: integrating diverse controls over carbon cycling in arctic and boreal ecosystems

    NASA Astrophysics Data System (ADS)

    Mack, M. C.; Alexander, H. D.; DeMarco, J.; Melvin, A.

    2012-12-01

    Climate is warming more rapidly in the tundra and forests of high northern latitudes than any other place on earth. Large, globally-important stocks of carbon (C) reside in these ecosystems. Characterized by cold, moist climate and frozen soils, these ecosystems have historically acted as a net sink for atmospheric C: they remove more C from the atmosphere on an annual basis than they release, resulting in the accumulation of large stocks in soils and plants. With warming climate comes the potential for fundamental changes in ecological controls over C cycling. Plant growth is limited by both low temperature and the slow regeneration of nutrients such as nitrogen (N). If warming stimulates plant growth by alleviating these limitations, than C uptake may increase. Indeed, satellite indices of greening as well as observations of shrub expansion and northern migration of the arctic treeline point towards increased plant productivity concurrent with climate warming. But as soils warm, microbial decomposition and release of C to the atmosphere, as well as disturbances such as wildfire or thermal erosion (thermokarst), are likely to increase, and it is unclear whether increased C loss may balance or even outweigh increased production, at least on the time-scale of decades to centuries. Understanding the net outcome of these two processes is important because it determines the sign of the feedback between the arctic/boreal C cycle and climate. A positive feedback, where warming increases C losses more than uptake, would amplify anthropogenic changes in climate, accelerating warming and destabilizing feedbacks between ecosystems and the atmosphere. A negative feedback, by contrast, where warming increases C uptake more than losses, would dampen the anthropogenic signal and stabilize climate. This presentation will focus on three general areas of ecological control over net ecosystem C balance in arctic and boreal ecosystems: nutrient availability, changing disturbance regimes, and changing plant species composition.

  7. Local Versus Landscape Control of Leaf Litter Chemistry on a Diverse Tropical Island

    NASA Astrophysics Data System (ADS)

    Erickson, H. E.; Helmer, E. H.; Brandeis, T. J.; Lugo, A. E.

    2008-12-01

    Recent advances in remote sensing technologies offer the opportunity to map terrestrial landscapes to broad physiognomic classes. A question that arises is whether additional local or landscape-scale information is needed to describe and model ecosystem properties at large, regional scales. Soils exhibit biogeochemical heterogeneity at multiple scales. Many soil nutrients are likely under more regional scale control due to gradients in climate and lithology, while others under more local control due to effects of species composition and topographic position. To examine some of these processes, we analyzed 11 elements in O horizon leaf litter from 147 Forest Inventory and Analysis (FIA) plots systematically located across the island of Puerto Rico. We then asked whether there were differences according to 1: Holdridge life zone, 2: forest cover type (primarily evergreen vs. drought deciduous broadleaf), derived from remotely sensed vegetation data in 2000 combined with coarse-scale geology (karst vs. non-karst), and 3: forest assemblages, based on tree survey data from the FIA plots. Three elements (C, Ca, and Mn) differed by Holdridge life zone, 2 elements (C, Ca) by 2000 forest cover type, 6 by geology (C, P, Ca, Mn, Al, and Fe), and 10 (including N) by groups of forest assemblages. As well, across and within several forest assemblages, leaf litter N and P were positively related to the basal area of putatively N-fixing tree legumes. These findings confirm the role of species in contributing to the spatial heterogeneity of N and P and suggest that without detailed data on vegetation composition, scaling up to landscapes may be problematic for some elements.

  8. The diverse, dynamic new world of global tobacco control? An analysis of participation in the Conference of the Parties to the WHO Framework Convention on Tobacco Control

    PubMed Central

    Plotnikova, Evgeniya; Hill, Sarah E; Collin, Jeff

    2014-01-01

    Introduction The increasingly inequitable impacts of tobacco use highlight the importance of ensuring developing countries ongoing participation in global tobacco control. The WHO Framework Convention on Tobacco Control (FCTC) has been widely regarded as reflecting the high engagement and effective influence of developing countries. Methods We examined participation in FCTC governance based on records from the first four meetings of the Conference of the Parties (COP), comparing representation and delegate diversity across income levels and WHO regions. Results While attendance at the COP sessions is high, there are substantial disparities in the relative representation of different income levels and regions, with lower middle and low income countries contributing only 18% and 10% of total meeting delegates, respectively. In regional terms, Europe provided the single largest share of delegates at all except the Durban (2008) meeting. Thirty-nine percent of low income countries and 27% of those from Africa were only ever represented by a single person delegation compared with 10% for high income countries and 11% for Europe. Rotation of the COP meeting location outside of Europe is associated with better representation of other regions and a stronger presence of delegates from national ministries of health and focal points for tobacco control. Conclusions Developing countries face particular barriers to participating in the COP process, and their engagement in global tobacco control is likely to diminish in the absence of specific measures to support their effective participation. PMID:23152101

  9. Mechanistic controls on diverse fates of terrestrial organic components in the East China Sea

    NASA Astrophysics Data System (ADS)

    Zhu, Chun; Wagner, Thomas; Talbot, Helen M.; Weijers, Johan W. H.; Pan, Jian-Ming; Pancost, Richard D.

    2013-09-01

    Terrestrial carbon transferred from the land to sea is a critical component of the global carbon cycle. A range of geochemical proxies has been developed to fingerprint the fate of terrestrial organic matter (TOM) in marine sediments. However, discrepancies among different proxies limit our ability to quantify and interpret the terrestrial signals in marine sediments, with consequences for the investigation of both the modern carbon cycle and past environmental change. To mechanistically understand these discrepancies, we examined the distributions of a range of terrestrial proxies and their aquatic counterparts (i.e. marine proxies) in the Yangtze river-East China Sea (YR-ECS) shelf system, where TOM experiences extensive modification during transport and burial. TOM proxies in the YR-ECS system collectively fit a power-law model but with distinct attenuation rates (the a? values) for individual molecular proxy groups. Among a range of TOM proxies, the modeled a? values decrease in the order: soil-marker BHPs > triterpenols > lignin > HMW n-alkanols > branched GDGTs > HMW n-alkanes for biomarkers; and Rsoil > BIT > %TOMiso for proxies tracing %TOM. Rapid loss of TOM components through dissociation in the narrow estuary, followed by oxidation over the wide open shelf, are best described by power curves. Inherent chemical reactivity (i.e. the number of functional groups), responses to hydraulic sorting, and in situ production regulate the individual attenuation rates. Of them, chemical reactivity plays the most important role on proxy behavior, supported by a strong correlation between a? values and standard molal Gibbs energies. Both, physical protection and chemical reactivity fundamentally control the overall behavior of TOM components, with the relative importance being setting-dependant: The former is relatively important in the estuary, whereas the later is the primary control over the open shelf. Moreover, regional variation of different marine-counterparts is also significant over the river-ECS shelf system, seemingly regulated by regional nutrient distributions. Therefore, for %TOM estimates using molecular ratio approaches, the specific behavior of individual terrestrial components and marine-counterparts and the physical, biological and chemical characteristics of depositional settings all need to be considered.

  10. Single-pulse femtosecond laser Bessel beams drilling of high-aspect-ratio microholes based on electron dynamics control

    NASA Astrophysics Data System (ADS)

    Zhao, Weiwei; Li, Xiaowei; Xia, Bo; Yan, Xueliang; Han, Weina; Lu, Yongfeng; Jiang, Lan

    2014-11-01

    Microholes drilling has attracted extensive research efforts for its broad applications in photonics, microfluidics, optical fibers and many other fields. A femtosecond (fs) laser is a promising tool for high-precision materials processing with reduced recast/microcracks and minimized heat affected zones. But there remain many challenges in hole drilling using conventional fs laser with Gaussian beams, such as low aspect ratio and taper effects. We report small-diameter and high-aspect-ratio microholes with taper free drilling in PMMA (polymethyl methacrylate) using single-pulse fs laser Bessel beams. Axicon is used to transform Gaussian beams into Bessel beams, which then irradiate in the sample by a telescope consisting of plano-convex lens and microscope objective. Using this technique, we enhance the aspect ratio of microholes by 55 times as compared with Gaussian beams. We attribute this high aspect ratio and high quality microholes formation to the unique spatial intensity distribution and propagation stability of Bessel beams, which can effectively adjust the transient localized electron density distribution leading to a long and uniform localized-interacted zone. By using the optimized pulse energy and focal depth position, the microholes diameter ranges between 1.4-2.1 ?m and the aspect ratio can exceed 460. This efficient technique is of great potentials for fabrication of microphotonics devices and microfluidics.

  11. Controlling and culturing diversity: experimental zoology before World War II and Vienna's Biologische Versuchsanstalt.

    PubMed

    Logan, Cheryl A; Brauckmann, Sabine

    2015-04-01

    Founded in Vienna in 1903, the Institute for Experimental Biology pioneered the application of experimental methods to living organisms maintained for sustained periods in captivity. Its Director, the zoologist Hans Przibram, oversaw until 1938, the attempt to integrate ontogeny with studies of inheritance using precise and controlled measurements of the impact of environmental influences on the emergence of form and function. In the early years, these efforts paralleled and even fostered the emergence of experimental biology in America. But fate intervened. Though the Institute served an international community, most of its resident scientists and staff were of Jewish ancestry. Well before the Nazis entered Austria in 1938, these men and women were being fired and driven out; some, including Przibram, were eventually killed. We describe the unprecedented facilities built and the topics addressed by the several departments that made up this Institute, stressing those most relevant to the establishment and success of the Journal of Experimental Zoology, which was founded just a year later. The Institute's diaspora left an important legacy in North America, perhaps best embodied by the career of the developmental neuroscientist Paul Weiss. PMID:25857375

  12. The Diversity of the Pollen Tube Pathway in Plants: Toward an Increasing Control by the Sporophyte

    PubMed Central

    Lora, Jorge; Hormaza, José I.; Herrero, María

    2016-01-01

    Plants, unlike animals, alternate multicellular diploid, and haploid generations in their life cycle. While this is widespread all along the plant kingdom, the size and autonomy of the diploid sporophyte and the haploid gametophyte generations vary along evolution. Vascular plants show an evolutionary trend toward a reduction of the gametophyte, reflected both in size and lifespan, together with an increasing dependence from the sporophyte. This has resulted in an overlooking of the importance of the gametophytic phase in the evolution of higher plants. This reliance on the sporophyte is most notorious along the pollen tube journey, where the male gametophytes have to travel a long way inside the sporophyte to reach the female gametophyte. Along evolution, there is a change in the scenery of the pollen tube pathway that favors pollen competition and selection. This trend, toward apparently making complicated what could be simple, appears to be related to an increasing control of the sporophyte over the gametophyte with implications for understanding plant evolution. PMID:26904071

  13. Role of vegetation and edaphic factors in controlling diversity and use of different carbon sources in semi-arid ecosystems

    NASA Astrophysics Data System (ADS)

    Lohse, K. A.; McLain, J. E.; Harman, C. J.; Sivapalan, M.; Troch, P. A.

    2010-12-01

    Microbially-mediated soil carbon cycling is closely linked to soil moisture and temperature. Climate change is predicted to increase intra-annual precipitation variability (i.e. less frequent yet more intense precipitation events) and alter biogeochemical processes due to shifts in soil moisture dynamics and inputs of carbon. However, the responses of soil biology and chemistry to predicted climate change, and their concomitant feedbacks on ecosystem productivity and biogeochemical processes are poorly understood. We collected soils at three different elevations in the Santa Catalina Mountains, AZ and quantified carbon utilization during pre-monsoon precipitation conditions. Contrasting parent materials (schist and granite) were paired at each elevation. We expected climate to determine the overall activity of soil fungal and bacterial communities and diversity of soil C utilization, and differences in parent material to modify these responses through controls on soil physical properties. We used EcoPlateTM C utilization assays to determine the relative abundance of soil bacterial and fungal populations and rate and diversity of carbon utilization. Additional plates were incubated with inhibitors selective to fungal or bacterial activity to assess relative contribution of these microbial groups to overall C utilization. We analyzed soils for soil organic matter, total C and N, particle size analysis and soil moisture content via both gravimetric and volumetric methods to assess the influences of soil physical and chemical properties on the measured biological responses. Consistent with our expectations, overall microbial activity was highest at the uppermost conifer elevation sites compared to the middle and lower elevation sites. In contrast to our expectations, however, overall activity was lower at the mid elevation oak woodland sites compared to the low elevation desert sites. Also consistent with our expectations was the observation that overall activities were consistently higher in schist parent material compared to granite. Though differences between canopy and intercanopy carbon utilization were subtle, the diversity of carbon utilization differed, suggesting a potential role of root exudates in governing C utilization in these semiarid soils. Findings from this study suggest that soil physical properties due to parent material have primary impacts in constraining microbial growth and carbon utilization under changing climate conditions.

  14. Comparative genomic analysis reveals new aspects of the biology and secondary metabolism of biological control strains of Pseudomonas spp.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To explore the genomic diversity of biocontrol strains of Pseudomonas spp., we derived high quality draft sequences of seven strains that suppress plant disease. The strains were isolated from the phyllosphere of pear (P. fluorescens A506), the rhizosphere of wheat (three strains of P. fluorescens ...

  15. Evaluation of carbonate pore system under texture control for prediction of microporosity aspect ratio and shear wave velocity

    NASA Astrophysics Data System (ADS)

    Lima Neto, Irineu A.; Missgia, Roseane M.; Ceia, Marco A.; Archilha, Nathaly L.; Hollis, Cathy

    2015-06-01

    This work evaluates a suite of carbonate rocks from Albian age in the Campos Basin - Brazil, complemented by data from the literature, totaling 472 samples with detailed description of diagenetic features, quantitative mineralogy analyses, and P- and S-wave velocities (Vp and Vs) measured at three ranges of effective pressure loading: low (5-7.5 MPa), moderate (20 MPa) and high (40-50 MPa) values. Digital image analysis (DIA) was applied on microtomography (?CT) images to quantitatively describe the macro-mesopore system of the Albian carbonates, and was extended to characterize different textures from literature data to estimate reference values for carbonates. The methodology utilized to predict the aspect ratio of microporosity assumes three pore-space scales in two representative scenarios: 1) measured macro-mesopore aspect ratio from DIA, and 2) predicted microporosity aspect ratio, using Vp measurement as the main input parameter. The differential effective medium model (DEMM) is combined with analytical theories of data analysis to characterize microporosity. Shear modulus and microporosity aspect ratio calibrated by this methodology were used to predict Vs, which was compared to experimental data, resulting in a good match for all samples. Polynomial curves are fitted with a variety of carbonate textures by velocities at effective pressure and bulk porosity crossplots, establishing important relationships for velocity prediction. The effects of effective pressure on the pore system within dry plugs of Albian samples were evaluated by combining triaxial measurements at 0-10 MPa, relative pore volume reduction (RPVR) and microporosity aspect ratio prediction. According to the results, micropores that exhibit low aspect ratio tend to close with stress and cause an increase on Vp and Vs. A wide textural heterogeneity of data base and different digital image analysis and resolutions were employed successfully, combining rock physics methodologies and concepts to characterize carbonate pore system as microporosity and pressure effects.

  16. Diversity of bacterial communities that colonize the filter units used for controlling plant pathogens in soilless cultures.

    PubMed

    Renault, David; Vallance, Jessica; Dniel, Franck; Wery, Nathalie; Godon, Jean Jacques; Barbier, Georges; Rey, Patrice

    2012-01-01

    In recent years, increasing the level of suppressiveness by the addition of antagonistic bacteria in slow filters has become a promising strategy to control plant pathogens in the recycled solutions used in soilless cultures. However, knowledge about the microflora that colonize the filtering columns is still limited. In order to get information on this issue, the present study was carried out over a 4-year period and includes filters inoculated or not with suppressive bacteria at the start of the filtering process (two or three filters were used each year). After 9months of filtration, polymerase chain reaction (PCR)-single strand conformation polymorphism analyses point out that, for the same year of experiment, the bacterial communities from control filters were relatively similar but that they were significantly different between the bacteria-amended and control filters. To characterize the changes in bacterial communities within the filters, this microflora was studied by quantitative PCR, community-level physiological profiles, and sequencing 16SrRNA clone libraries (filters used in year1). Quantitative PCR evidenced a denser bacterial colonization of the P-filter (amended with Pseudomonas putida strains) than control and B-filter (amended with Bacillus cereus strains). Functional analysis focused on the cultivable bacterial communities pointed out that bacteria from the control filter metabolized more carbohydrates than those from the amended filters whose trophic behaviors were more targeted towards carboxylic acids and amino acids. The bacterial communities in P- and B-filters both exhibited significantly more phylotype diversity and markedly distinct phylogenetic compositions than those in the C-filter. Although there were far fewer Proteobacteria in B- and P-filters than in the C-filter (22% and 22% rather than 69% of sequences, respectively), the percentages of Firmicutes was much higher (44% and 55% against 9%, respectively). Many Pseudomonas species were also found in the bacterial communities of the control filter. The persistence of the amended suppressive-bacteria in the filters is discussed with regards to the management of suppressive microflora in soilless culture. PMID:22015683

  17. Engaging adolescent girls from linguistically diverse and low income backgrounds in school sport: a pilot randomised controlled trial.

    PubMed

    Dudley, Dean A; Okely, Anthony D; Pearson, Philip; Peat, Jennifer

    2010-03-01

    The purpose of this study was to determine the feasibility, acceptability, and potential efficacy of a school-based physical activity program delivered during school sport time among adolescent girls from low income predominately linguistically diverse backgrounds in New South Wales, Australia. Using a 3-month, 2-arm, parallel-group pilot RCT design, 38 adolescent girls (Year 11) were recruited to participate in the program and randomised into intervention (n=17) or control groups (n=21). The intervention program aimed to increase physical activity by improving enjoyment, physical self-perception and perceived competence. Baseline and follow-up (12 weeks) assessments included enjoyment of physical activity, physical self-perception, and objectively measured physical activity during school sport sessions. Process data were collected through observations of lessons, attendance records, and interviews with participants and staff. Recruitment (63%) and retention (68%) goals were less than anticipated but similar to other studies. Participation was higher for the intervention (72%) than the control (60%) group and the intervention group reported high levels of satisfaction with the program. At follow-up, girls in the intervention group, compared with the control group, showed greater improvement in their enjoyment of physical activity during school sport (adjusted mean difference=3.8, 95% Confidence Interval [CI] -2.4, 10.1; Cohen's d=0.42 standard deviation units) and body image (adjusted difference mean=1.0, 95% CI -0.4, 2.3; d=0.50). There was a smaller decline in participation in physical activity during school sport (adjusted mean=13.6, 95% CI -21.8, 48.9; d=0.24). This study highlights major barriers confronting adolescent girls' participation in school sport. Some of these include teacher attitudes and support, activities and programming, purpose and distinction, and student input. Negotiating these barriers and overcoming them in a school setting appears feasible with support from the entire school community. PMID:19574099

  18. Regulatory aspects

    NASA Astrophysics Data System (ADS)

    Stern, Arthur M.

    1986-07-01

    At this time, there is no US legislation that is specifically aimed at regulating the environmental release of genetically engineered organisms or their modified components, either during the research and development stage or during application. There are some statutes, administered by several federal agencies, whose language is broad enough to allow the extension of intended coverage to include certain aspects of biotechnology. The one possible exception is FIFRA, which has already brought about the registration of several natural microbial pesticides but which also has provision for requiring the registration of strain improved microbial pesticides. Nevertheless, there may be gaps in coverage even if all pertinent statutes were to be actively applied to the control of environmental release of genetically modified substances. The decision to regulate biotechnology under TSCA was justified, in part, on the basis of its intended role as a gap-filling piece of environmental legislation. The advantage of regulating biotechnology under TSCA is that this statute, unlike others, is concerned with all media of exposure (air, water, soil, sediment, biota) that may pose health and environmental hazards. Experience may show that extending existing legislation to regulate biotechnology is a poor compromise compared to the promulgation of new legislation specifically designed for this purpose. It appears that many other countries are ultimately going to take the latter course to regulate biotechnology.

  19. Exploiting Natural Variation of Secondary Metabolism Identifies a Gene Controlling the Glycosylation Diversity of Dihydroxybenzoic Acids in Arabidopsis thaliana

    PubMed Central

    Li, Xu; Svedin, Elisabeth; Mo, Huaping; Atwell, Susanna; Dilkes, Brian P.; Chapple, Clint

    2014-01-01

    Plant secondary metabolism is an active research area because of the unique and important roles the specialized metabolites have in the interaction of plants with their biotic and abiotic environment, the diversity and complexity of the compounds and their importance to human medicine. Thousands of natural accessions of Arabidopsis thaliana characterized with increasing genomic precision are available, providing new opportunities to explore the biochemical and genetic mechanisms affecting variation in secondary metabolism within this model species. In this study, we focused on four aromatic metabolites that were differentially accumulated among 96 Arabidopsis natural accessions as revealed by leaf metabolic profiling. Using UV, mass spectrometry, and NMR data, we identified these four compounds as different dihydroxybenzoic acid (DHBA) glycosides, namely 2,5-dihydroxybenzoic acid (gentisic acid) 5-O-?-D-glucoside, 2,3-dihydroxybenzoic acid 3-O-?-D-glucoside, 2,5-dihydroxybenzoic acid 5-O-?-D-xyloside, and 2,3-dihydroxybenzoic acid 3-O-?-D-xyloside. Quantitative trait locus (QTL) mapping using recombinant inbred lines generated from C24 and Col-0 revealed a major-effect QTL controlling the relative proportion of xylosides vs. glucosides. Association mapping identified markers linked to a gene encoding a UDP glycosyltransferase gene. Analysis of Transfer DNA (T-DNA) knockout lines verified that this gene is required for DHBA xylosylation in planta and recombinant protein was able to xylosylate DHBA in vitro. This study demonstrates that exploiting natural variation of secondary metabolism is a powerful approach for gene function discovery. PMID:25173843

  20. What Makes Group MET Work? A Randomized Controlled Trial of College Student Drinkers in Mandated Alcohol Diversion

    PubMed Central

    LaChance, Heather; Feldstein Ewing, Sarah W.; Bryan, Angela D.; Hutchison, Kent E.

    2009-01-01

    Nationally, college drinkers exhibit the highest rates of alcohol consumption and represent the largest percentage of problem drinkers. Group motivational enhancement therapy (GMET) has been found to catalyze problem drinking reductions among college student samples. While research supporting the use of single-session GMET in college samples (general and mandated) is emergent, no studies have evaluated a comprehensive model of the potential active ingredients of this group intervention. College students (N = 206; 88% Caucasian; 63% male; M age = 18.6) mandated to a university alcohol diversion program were randomly assigned to one of three conditions: the standard-of-care two-session Focus on Alcohol Concerns education group (FAC), a single group motivational enhancement therapy (GMET), or a single Alcohol Information-only control group (AI) to evaluate the role of five putative mediators: readiness to change, self-efficacy, perceived risk, norm estimates, and positive drinking expectancies. At three and six month follow-ups, GMET students demonstrated greater reductions in problem drinking outcomes (drinks per drinking day, hazardous drinking symptoms, and alcohol-related problems). Of the five mediators proposed, only self-efficacy emerged as a significant mediator. PMID:20025366

  1. The COPE healthy lifestyles TEEN randomized controlled trial with culturally diverse high school adolescents: Baseline characteristics and methods

    PubMed Central

    Melnyk, Bernadette Mazurek; Kelly, Stephanie; Jacobson, Diana; Belyea, Michael; Shaibi, Gabriel; Small, Leigh; O’Haver, Judith; Marsiglia, Flavio Francisco

    2014-01-01

    Obesity and mental health disorders remain significant public health problems in adolescents. Substantial health disparities exist with minority youth experiencing higher rates of these problems. Schools are an outstanding venue to provide teens with skills needed to improve their physical and mental health, and academic performance. In this paper, the authors describe the design, intervention, methods and baseline data for a randomized controlled trial with 779 culturally diverse high-school adolescents in the southwest United States. Aims for this prevention study include testing the efficacy of the COPE TEEN program versus an attention control program on the adolescents’ healthy lifestyle behaviors, Body Mass Index (BMI) and BMI%, mental health, social skills and academic performance immediately following the intervention programs, and at six and 12 months post interventions. Baseline findings indicate that greater than 40% of the sample is either overweight (n = 148, 19.00%) or obese (n = 182, 23.36%). The predominant ethnicity represented is Hispanic (n = 526, 67.52%). At baseline, 15.79%(n = 123) of the students had above average scores on the Beck Youth Inventory Depression subscale indicating mildly (n = 52, 6.68%), moderately (n = 47, 6.03%), or extremely (n = 24, 3.08%) elevated scores (see 1). Anxiety scores were slightly higher with 21.56% (n = 168) reporting responses suggesting mildly (n = 81, 10.40%), moderately (n = 58, 7.45%) or extremely (n = 29, 3.72%) elevated scores. If the efficacy of the COPE TEEN program is supported, it will offer schools a curriculum that can be easily incorporated into high school health courses to improve adolescent healthy lifestyle behaviors, psychosocial outcomes and academic performance. PMID:23748156

  2. Single DNA molecules on freestanding and supported cationic lipid bilayers: diverse conformational dynamics controlled by the local bilayer properties

    NASA Astrophysics Data System (ADS)

    Herold, Christoph; Schwille, Petra; Petrov, Eugene P.

    2016-02-01

    We present experimental results on the interaction of DNA macromolecules with cationic lipid membranes with different properties, including freestanding membranes in the fluid and gel state, and supported lipid membranes in the fluid state and under conditions of fluid–gel phase coexistence. We observe diverse conformational dynamics of membrane-bound DNA molecules controlled by the local properties of the lipid bilayer. In case of fluid-state freestanding lipid membranes, the behaviour of DNA on the membrane is controlled by the membrane charge density: whereas DNA bound to weakly charged membranes predominantly behaves as a 2D random coil, an increase in the membrane charge density leads to membrane-driven irreversible DNA collapse and formation of subresolution-sized DNA globules. On the other hand, electrostatic binding of DNA macromolecules to gel-state freestanding membranes leads to completely arrested diffusion and conformational dynamics of membrane-adsorbed DNA. A drastically different picture is observed in case of DNA interaction with supported cationic lipid bilayers: When the supported bilayer is in the fluid state, membrane-bound DNA molecules undergo 2D translational Brownian motion and conformational fluctuations, irrespectively of the charge density of the supported bilayer. At the same time, when the supported cationic membrane shows fluid–gel phase coexistence, membrane-bound DNA molecules are strongly attracted to micrometre-sized gel-phase domains enriched with the cationic lipid, which results in 2D compaction of the membrane-bound macromolecules. This DNA compaction, however, is fully reversible, and disappears as soon as the membrane is heated above the fluid–gel coexistence. We also discuss possible biological implications of our experimental findings.

  3. The COPE healthy lifestyles TEEN randomized controlled trial with culturally diverse high school adolescents: baseline characteristics and methods.

    PubMed

    Melnyk, Bernadette Mazurek; Kelly, Stephanie; Jacobson, Diana; Belyea, Michael; Shaibi, Gabriel; Small, Leigh; O'Haver, Judith; Marsiglia, Flavio Francisco

    2013-09-01

    Obesity and mental health disorders remain significant public health problems in adolescents. Substantial health disparities exist with minority youth experiencing higher rates of these problems. Schools are an outstanding venue to provide teens with skills needed to improve their physical and mental health, and academic performance. In this paper, the authors describe the design, intervention, methods and baseline data for a randomized controlled trial with 779 culturally diverse high-school adolescents in the southwest United States. Aims for this prevention study include testing the efficacy of the COPE TEEN program versus an attention control program on the adolescents' healthy lifestyle behaviors, Body Mass Index (BMI) and BMI%, mental health, social skills and academic performance immediately following the intervention programs, and at six and 12 months post interventions. Baseline findings indicate that greater than 40% of the sample is either overweight (n = 148, 19.00%) or obese (n = 182, 23.36%). The predominant ethnicity represented is Hispanic (n = 526, 67.52%). At baseline, 15.79% (n = 123) of the students had above average scores on the Beck Youth Inventory Depression subscale indicating mildly (n = 52, 6.68%), moderately (n = 47, 6.03%), or extremely (n = 24, 3.08%) elevated scores (see Table 1). Anxiety scores were slightly higher with 21.56% (n = 168) reporting responses suggesting mildly (n = 81, 10.40%), moderately (n = 58, 7.45%) or extremely (n = 29, 3.72%) elevated scores. If the efficacy of the COPE TEEN program is supported, it will offer schools a curriculum that can be easily incorporated into high school health courses to improve adolescent healthy lifestyle behaviors, psychosocial outcomes and academic performance. PMID:23748156

  4. Outbreak Control and Clinical, Pathological, and Epidemiological Aspects and Molecular Characterization of a Bovine Herpesvirus Type 5 on a Feedlot Farm in So Paulo State

    PubMed Central

    Ferreira Vicente, Accia; Appolinario, Camila Michele; Allendorf, Susan Dora; Gasparini Baraldi, Thas; Cortez, Adriana; Bryan Heinemann, Marcos; Reinaldo Silva Fonseca, Clovis; Cristina Pelcia, Vanessa; Devid Ribeiro, Bruna Leticia; Hiromi Okuda, Liria; Pituco, Edviges Maristela

    2015-01-01

    This paper describes the control, epidemiological, pathological, and molecular aspects of an outbreak of meningoencephalitis in calves due to bovine herpesvirus 5 at a feedlot with 540 animals in So Paulo State, Brazil. The introduction of new animals and contact between the resident animals and the introduced ones were most likely responsible for virus transmission. Bovine herpesvirus 1 vaccine was used, resulting in the efficacy of the outbreak control, although two bovine herpesvirus 1 positive animals, vaccinated and revaccinated, presented meningoencephalitis, thereby characterizing vaccinal failure. PMID:26090469

  5. Multidimensional display controller for displaying to a user an aspect of a multidimensional space visible from a base viewing location along a desired viewing orientation

    DOEpatents

    Davidson, George S.; Anderson, Thomas G.

    2001-01-01

    A display controller allows a user to control a base viewing location, a base viewing orientation, and a relative viewing orientation. The base viewing orientation and relative viewing orientation are combined to determine a desired viewing orientation. An aspect of a multidimensional space visible from the base viewing location along the desired viewing orientation is displayed to the user. The user can change the base viewing location, base viewing orientation, and relative viewing orientation by changing the location or other properties of input objects.

  6. Addressing Diversity in Teacher Education Programs

    ERIC Educational Resources Information Center

    Valentin, Sylvia

    2006-01-01

    Different aspects of diversity have been explored in order to assess whether preservice teachers are being prepared to meet the needs of their diverse student population. Diversity continues to be examined in a fragmented way by looking at issues separately. It seems necessary that prior to assessing preservice teachers' competence in diversity,

  7. Controllable synthesis of high aspect ratio Mg2B2O5 nanowires and their applications in reinforced polyhydroxyalkanoate composites

    NASA Astrophysics Data System (ADS)

    Mo, Zhao-Jun; Chen, Jin-Peng; Lin, Jing; Fan, Ying; Liang, Chun-Yong; Wang, Hong-Shui; Xu, Xue-Wen; Hu, Long; Tang, Cheng-Chun

    2014-05-01

    Highly pure magnesium borate (Mg2B2O5) nanowires with an average diameter of ~ 30 nm, an average length of ~ 15 ?m, and a high aspect ratio of ~ 500 have been synthesized on a large scale via a two-step method. MgBO2(OH) nanowires with high aspect ratios were first prepared via a PVP-assisted hydrothermal technique. Using these nanowires as precursors, single crystalline Mg2B2O5 nanowires were synthesized by post-annealing treatment at a relatively low temperature of 700 C. The important effect of the MgBO2(OH)Mg2B2O5 conversion process on the morphology of the Mg2B2O5 nanowires was investigated and it was indicated that the recrystallization process plays an important role in the protection of the one-dimensional (1D) nanostructure. Moreover, the rigidity and the toughness of the Mg2B2O5 nanowire-reinforced PHA composites were tremendously improved compared to those of the pure PHA. Our results demonstrate the effectiveness of Mg2B2O5 nanowires for reinforcement applications in polymer composites.

  8. The influence of phytoplankton productivity, temperature and environmental stability on the control of copepod diversity in the North East Atlantic

    NASA Astrophysics Data System (ADS)

    Nogueira, Enrique; Gonzlez-Nuevo, Gonzalo; Valds, Luis

    2012-05-01

    The patterns of copepod species richness (S) and their relationship with phytoplankton productivity, temperature and environmental stability were investigated at climatological, seasonal and year-to-year time scales as well as scales along latitudinal and oceanic-neritic gradients using monthly time series of the Continuous Plankton Recorder (CPR) Survey collected in the North East Atlantic between 1958 and 2006. Time series analyses confirmed previously described geographic patterns. Equatorward and towards neritic environments, the climatological average of S increases and the variance explained by the seasonal cycle decreases. The bi-modal character of seasonality increases equatorward and the timing of the seasonal cycle takes place progressive earlier equatorward and towards neritic environments. In the long-term, the climatological average of S decreased significantly (p < 0.001) between 1958 and 2006 in the Bay of Biscay and North Iberian shelf at a rate of ca. 0.04 year-1, and increased at the same rate between 1991 and 2006 in the northernmost oceanic location. The climatological averages of S correlate positively with those of the index of seasonality of phytoplankton productivity (ratio between the minimum and maximum monthly values of surface chlorophyll) and sea surface temperature, and negatively with those of the proxy for environmental stability (monthly frequency of occurrence of daily averaged wind speed exceeding 10 m s-1). The seasonal cycles of S and phytoplankton productivity (surface chlorophyll as proxy) exhibit similar features in terms of shape, timing and explained variance, but the relationship between the climatological averages of both variables is non-significant. From year-to-year, the annual averages of S correlate negatively with those of phytoplankton productivity and positively with those of sea surface temperature along the latitudinal gradient, and negatively with those of environmental stability along the oceanic-neritic gradient. The annual anomalies of S (i.e. factoring out geographic variation) show a unimodal relationship with those of sea surface temperature and environmental stability, with S peaking at intermediate values of the anomalies of these variables. The results evidence the role of seasonality of phytoplankton productivity on the control of copepod species richness at seasonal and climatological scales, giving support to the species richness-productivity hypothesis. Although sea surface temperature (SST) is indeed a good predictor of richness along the latitudinal gradient, it is unable to predict the increase of richness form oceanic to neritic environments, thus lessening the generality of the species richness-energy hypothesis. Meteo-hydrographic disturbances (i.e. SST and wind speed anomalies as proxies), presumably through its role on mixed layer depth dynamics and turbulence and hence productivity, maximise local diversity when occurring at intermediate frequency and or intensity, thus providing support to the intermediate disturbance hypothesis on the control of copepod diversity.

  9. Low Genetic Diversity and Strong Geographical Structure of the Critically Endangered White-Headed Langur (Trachypithecus leucocephalus) Inferred from Mitochondrial DNA Control Region Sequences

    PubMed Central

    Wang, Weiran; Qiao, Yu; Pan, Wenshi; Yao, Meng

    2015-01-01

    Many Asian colobine monkey species are suffering from habitat destruction and population size decline. There is a great need to understand their genetic diversity, population structure and demographic history for effective species conservation. The white-headed langur (Trachypithecus leucocephalus) is a Critically Endangered colobine species endemic to the limestone karst forests in southwestern China. We analyzed the mitochondrial DNA (mtDNA) control region sequences of 390 fecal samples from 40 social groups across the main distribution areas, which represented one-third of the total extant population. Only nine haplotypes and 10 polymorphic sites were identified, indicating remarkably low genetic diversity in the species. Using a subset of 77 samples from different individuals, we evaluated genetic variation, population structure, and population demographic history. We found very low values of haplotype diversity (h = 0.570 ± 0.056) and nucleotide diversity (π = 0.00323 ± 0.00044) in the hypervariable region I (HVRI) of the mtDNA control region. Distribution of haplotypes displayed marked geographical pattern, with one population (Chongzuo, CZ) showing a complete lack of genetic diversity (having only one haplotype), whereas the other population (Fusui, FS) having all nine haplotypes. We detected strong population genetic structure among habit patches (ΦST = 0.375, P < 0.001). In addition, the Mantel test showed a significant correlation between the pairwise genetic distances and geographical distances among social groups in FS (correlation coefficient = 0.267, P = 0.003), indicting isolation-by-distance pattern of genetic divergence in the mtDNA sequences. Analyses of demographic history suggested an overall stable historical population size and modest population expansion in the last 2,000 years. Our results indicate different genetic diversity and possibly distinct population history for different local populations, and suggest that CZ and FS should be considered as one evolutionarily significant unit (ESU) and two management units (MUs) pending further investigation using nuclear markers. PMID:26057239

  10. Design aspects of a high-speed sensorless brushless dc motor using third harmonic back-emf for sensorless control

    NASA Astrophysics Data System (ADS)

    Wang, Kai; Shen, Jianxin; Zhou, Fengzheng; Fei, Weizhong

    2008-04-01

    There is increasing interest in high-speed permanent magnet (PM) brushless dc motors for a wide range of applications. Back-emf is often utilized for sensorless operation of permanent magnet brushless dc motors, by detecting the emf zero crossings. However, in high-speed motors, the free-wheeling diode conduction can last more than 30edeg. This can obscure the zero crossings of the phase EMF; therefore, it is preferable to utilize the third harmonic emf instead of the phase emf. In this paper, some design aspects related to this high-speed sensorless operation are presented, including a special nonoverlapping winding arrangement and magnet segmenting technique. Finally, the experimental results confirmed the validity of the proposed design method.

  11. Endemic predators, invasive prey and native diversity

    PubMed Central

    Wanger, Thomas C.; Wielgoss, Arno C.; Motzke, Iris; Clough, Yann; Brook, Barry W.; Sodhi, Navjot S.; Tscharntke, Teja

    2011-01-01

    Interactions between native diversity and invasive species can be more complex than is currently understood. Invasive ant species often substantially reduce diversity in the native ants diversity that act as natural control agents for pest insects. In Indonesia (on the island of Sulawesi), the third largest cacao producer worldwide, we show that a predatory endemic toad (Ingerophrynus celebensis) controls invasive ant (Anoplolepis gracilipes) abundance, and positively affects native ant diversity. We call this the invasive-naivety effect (an opposite of enemy release), whereby alien species may not harbour anti-predatory defences against a novel native predator. A positive effect of the toads on native ants may facilitate their predation on insect vectors of cacao diseases. Hence, toads may increase crop yield, but further research is needed on this aspect. Ironically, amphibians are globally the most threatened vertebrate class and are strongly impacted by the conversion of rainforest to cacao plantations in Sulawesi. It is, therefore, crucial to manage cacao plantations to maintain these endemic toads, as they may provide critical ecosystem services, such as invasion resistance and preservation of native insect diversity. PMID:20826488

  12. Endemic predators, invasive prey and native diversity.

    PubMed

    Wanger, Thomas C; Wielgoss, Arno C; Motzke, Iris; Clough, Yann; Brook, Barry W; Sodhi, Navjot S; Tscharntke, Teja

    2011-03-01

    Interactions between native diversity and invasive species can be more complex than is currently understood. Invasive ant species often substantially reduce diversity in the native ants diversity that act as natural control agents for pest insects. In Indonesia (on the island of Sulawesi), the third largest cacao producer worldwide, we show that a predatory endemic toad (Ingerophrynus celebensis) controls invasive ant (Anoplolepis gracilipes) abundance, and positively affects native ant diversity. We call this the invasive-naivety effect (an opposite of enemy release), whereby alien species may not harbour anti-predatory defences against a novel native predator. A positive effect of the toads on native ants may facilitate their predation on insect vectors of cacao diseases. Hence, toads may increase crop yield, but further research is needed on this aspect. Ironically, amphibians are globally the most threatened vertebrate class and are strongly impacted by the conversion of rainforest to cacao plantations in Sulawesi. It is, therefore, crucial to manage cacao plantations to maintain these endemic toads, as they may provide critical ecosystem services, such as invasion resistance and preservation of native insect diversity. PMID:20826488

  13. Design verification and fabrication of active control systems for the DAST ARW-2 high aspect ratio wing, part 1

    NASA Technical Reports Server (NTRS)

    Mcgehee, C. R.

    1986-01-01

    A study was conducted under Drones for Aerodynamic and Structural Testing (DAST) program to accomplish the final design and hardware fabrication for four active control systems compatible with and ready for installation in the NASA Aeroelastic Research Wing No. 2 (ARW-2) and Firebee II drone flight test vehicle. The wing structure was designed so that Active Control Systems (ACS) are required in the normal flight envelope by integrating control system design with aerodynamics and structure technologies. The DAST ARW-2 configuration uses flutter suppression, relaxed static stability, and gust and maneuver load alleviation ACS systems, and an automatic flight control system. Performance goals and criteria were applied to individual systems and the systems collectively to assure that vehicle stability margins, flutter margins, flying qualities and load reductions are achieved.

  14. Design verification and fabrication of active control systems for the DAST ARW-2 high aspect ratio wing. Part 2: Appendices

    NASA Technical Reports Server (NTRS)

    Mcgehee, C. R.

    1986-01-01

    This is Part 2-Appendices of a study conducted under Drones for Aerodynamic and Structural Testing (DAST) Program to accomplish the final design and hardware fabrication for four active control systems compatible with and ready for installation in the NASA Aeroelastic Research Wing No. 2 (ARW-2) and Firebee II drone flight test vehicle. The wing structure was designed so that Active Control Systems (ACS) are required in the normal flight envelope by integrating control system design with aerodynamics and structure technologies. The DAST ARW-2 configuration uses flutter suppression, relaxed static stability, and gust and maneuver load alleviation ACS systems, and an automatic flight control system. Performance goals and criteria were applied to individual systems and the systems collectively to assure that vehicle stability margins, flutter margins, flying qualities, and load reductions were achieved.

  15. Neuroendocrine aspects of primary endogenous depression. XV: Mathematical modeling of nocturnal melatonin secretion in major depressives and normal controls.

    PubMed

    Sekula, L K; Lucke, J F; Heist, E K; Czambel, R K; Rubin, R T

    1997-03-24

    We previously reported a trend toward a higher mean nocturnal serum melatonin (MEL) concentration, based on 30-min blood sampling over 24 h, in 23 female definite endogenous depressive compared to 23 matched normal female control subjects, and no significant difference in 15 male depressives compared to their controls (Rubin et al., 1992). In both groups of patients vs. their controls, there also were trends toward an earlier MEL rise time, by about 30 min, and a later MEL peak time, by about 90 min. Because the offset of MEL secretion was not estimated in that study, the total duration of MEL secretion could not be determined. To further delineate the nocturnal MEL secretion curve, we modeled the MEL data by a linear-Beta model, a four-parameter adaptation of the Beta function. One parameter accounted-for baseline (diurnal) MEL concentration, two accounted for the shapes of the ascending and descending phases of the nocturnal secretion curve, and the fourth accounted for the area under the curve. The model permitted estimation of the start, peak, and end times of nocturnal MEL secretion. There again was a trend toward a higher mean nocturnal MEL concentration in the female depressives compared to their matched controls. There were no significant patient-control differences in secretion onset or peak times in either the women or the men except for nocturnal MEL offset time: the female patients had a trend toward a later offset time, by about 40 min, than their controls; this difference was not present in the men. With women and men analyzed together, the difference in nocturnal MEL offset time between patients and controls just reached significance (P < 0.05). The linear-Beta model appears to satisfactorily fit the MEL data and provides estimators of the onset, peak, and offset times of the activation phase of MEL secretion. This model may be applicable to more severely skewed 24-h hormone secretion curves, such as ACTH and cortisol. PMID:9109182

  16. Trypanosoma evansi and Surra: A Review and Perspectives on Transmission, Epidemiology and Control, Impact, and Zoonotic Aspects

    PubMed Central

    Desquesnes, Marc; Dargantes, Alan; Lai, De-Hua; Lun, Zhao-Rong; Holzmuller, Philippe; Jittapalapong, Sathaporn

    2013-01-01

    This paper reviews the transmission modes of Trypanosoma evansi. Its worldwide distribution is attributed to mechanical transmission. While the role of tabanids is clear, we raise questions on the relative role of Haematobia sp. and the possible role of Stomoxys sp. in delayed transmission. A review of the available trypanocidal drugs and their efficacy in various host species is useful for understanding how they interact in disease epidemiology, which is complex. Although there are similarities with other mechanically transmitted trypanosomes, T. evansi has a more complex epidemiology due to the diversity of its hosts and vectors. The impact of clinical and subclinical disease is difficult to establish. A model was developed for buffaloes in the Philippines, which could be transferred to other places and livestock systems. Since Trypanosoma evansi was reported in humans, further research is required to investigate its zoonotic potential. Surra remains a potentially emerging disease that is a threat to Australia, Spain, and France. A number of questions about the disease have yet to be resolved. This brief review of the basic knowledge of T. evansi suggests that there is renewed interest in the parasite, which is spreading and has a major economic impact. PMID:24151595

  17. Abdominal organ donation: surgical aspects and recommended practice guidelines for controlled donation of brain-dead donor.

    PubMed

    Matevossian, E; Kordzaia, D; Chkhaidze, Z; Khodeli, N; Partsakashvili, J; Khachiperadze, Z; Doll, D; Lobzhanidze, G

    2015-02-01

    The shortage of organ donors along with the increased number of waiting recipients have created the need for new strategies to expand the organ pool from donations after brain death. Organ procurement from brain-dead deceased donors is a complex task. Multiple, complicated operations are performed simultaneously. Very often, this involves numerous physicians and transplant coordinators. An extensive coordination between the thoracic and abdominal surgical teams is crucial for the successful procurement of all suitable organs. The quality of donor organs and the successful recovery therefore depends on a good communication. Organ procurement for transplantation should generally be performed in a calm and dignified atmosphere. The last wishes of the organ donor itself or the relatives must be respected unconditionally. In general, a dignified and respectful treatment of the organ donor is a condition sine qua non for each person involved in the process of organ procurement. The purpose of this article was to focus on the surgical aspects of organ donation after brain death. The proposed recommendations, in cases where they are applicable, are acceptable, however, one should never forget the importance of the ethical side of the issue with respect to the doctor-donating side relationship. PMID:25802455

  18. Tissue growth controlled by geometric boundary conditions: a simple model recapitulating aspects of callus formation and bone healing.

    PubMed

    Fischer, F Dieter; Zickler, Gerald A; Dunlop, John W C; Fratzl, Peter

    2015-06-01

    The shape of tissues arises from a subtle interplay between biochemical driving forces, leading to cell growth, division and extracellular matrix formation, and the physical constraints of the surrounding environment, giving rise to mechanical signals for the cells. Despite the inherent complexity of such systems, much can still be learnt by treating tissues that constantly remodel as simple fluids. In this approach, remodelling relaxes all internal stresses except for the pressure which is counterbalanced by the surface stress. Our model is used to investigate how wettable substrates influence the stability of tissue nodules. It turns out for a growing tissue nodule in free space, the model predicts only two states: either the tissue shrinks and disappears, or it keeps growing indefinitely. However, as soon as the tissue wets a substrate, stable equilibrium configurations become possible. Furthermore, by investigating more complex substrate geometries, such as tissue growing at the end of a hollow cylinder, we see features reminiscent of healing processes in long bones, such as the existence of a critical gap size above which healing does not occur. Despite its simplicity, the model may be useful in describing various aspects related to tissue growth, including biofilm formation and cancer metastases. PMID:26018964

  19. Controlled growth mode of high-aspect-ratio GaN nanorods by Ni/In/Ga catalyst

    NASA Astrophysics Data System (ADS)

    Ebaid, Mohamed; Kang, Jin-Ho; Key Lee, June; Ryu, Sang-Wan

    2013-09-01

    Gallium nitride nanorods (GaN NRs) were grown by employing a low melting point Ni/In/Ga alloy via metalorganic chemical vapour deposition. A small growth temperature window was observed in the range of 720-765 C, which is lower than typical temperatures used for the growth of GaN NRs assisted by metal catalyst. Tapered GaN NRs with triangular cross-section were produced at 750 C by vapour-solid (VS) growth mechanism. A slight increase of temperature to 765 C was able to change the growth mode to vapour-liquid-solid (VLS) and quasi-aligned GaN NRs with high aspect ratio were produced. Photoluminescence of both GaN NR morphologies measured at 10 K revealed only near band edge emission centred at 3.48 eV, which was blue-shifted from that of the bulk GaN estimated at 3.46 eV. Micro-Raman spectroscopy performed at 300 K exhibited that GaN NRs grown either by VS or VLS growth mechanisms are relatively free of strain.

  20. Expression of genes controlling fat deposition in two genetically diverse beef cattle breeds fed high or low silage diets

    PubMed Central

    2013-01-01

    Background Both genetic background and finishing system can alter fat deposition, thus indicating their influence on adipogenic and lipogenic factors. However, the molecular mechanisms underlying fat deposition and fatty acid composition in beef cattle are not fully understood. This study aimed to assess the effect of breed and dietary silage level on the expression patterns of key genes controlling lipid metabolism in subcutaneous adipose tissue (SAT) and longissimus lumborum (LL) muscle of cattle. To that purpose, forty bulls from two genetically diverse Portuguese bovine breeds with distinct maturity rates, Alentejana and Barrosã, were selected and fed either low (30% maize silage/70% concentrate) or high silage (70% maize silage/30% concentrate) diets. Results The results suggested that enhanced deposition of fatty acids in the SAT from Barrosã bulls, when compared to Alentejana, could be due to higher expression levels of lipogenesis (SCD and LPL) and β-oxidation (CRAT) related genes. Our results also indicated that SREBF1 expression in the SAT is increased by feeding the low silage diet. Together, these results point out to a higher lipid turnover in the SAT of Barrosã bulls when compared to Alentejana. In turn, lipid deposition in the LL muscle is related to the expression of adipogenic (PPARG and FABP4) and lipogenic (ACACA and SCD) genes. The positive correlation between ACACA expression levels and total lipids, as well trans fatty acids, points to ACACA as a major player in intramuscular deposition in ruminants. Moreover, results reinforce the role of FABP4 in intramuscular fat development and the SAT as the major site for lipid metabolism in ruminants. Conclusions Overall, the results showed that SAT and LL muscle fatty acid composition are mostly dependent on the genetic background. In addition, dietary silage level impacted on muscle lipid metabolism to a greater extent than on that of SAT, as evaluated by gene expression levels of adipogenic and lipogenic factors. Moreover, the response to diet composition evaluated through mRNA levels and fatty acid composition showed interesting differences between Alentejana and Barrosã bulls. These findings provide evidence that the genetic background should be taken into account while devising diet-based strategies to manipulate fatty acid composition of beef cattle tissues. PMID:23767408

  1. Brain training with non-action video games enhances aspects of cognition in older adults: a randomized controlled trial

    PubMed Central

    Ballesteros, Soledad; Prieto, Antonio; Mayas, Julia; Toril, Pilar; Pita, Carmen; Ponce de León, Laura; Reales, José M.; Waterworth, John

    2014-01-01

    Age-related cognitive and brain declines can result in functional deterioration in many cognitive domains, dependency, and dementia. A major goal of aging research is to investigate methods that help to maintain brain health, cognition, independent living and wellbeing in older adults. This randomized controlled study investigated the effects of 20 1-h non-action video game training sessions with games selected from a commercially available package (Lumosity) on a series of age-declined cognitive functions and subjective wellbeing. Two groups of healthy older adults participated in the study, the experimental group who received the training and the control group who attended three meetings with the research team along the study. Groups were similar at baseline on demographics, vocabulary, global cognition, and depression status. All participants were assessed individually before and after the intervention, or a similar period of time, using neuropsychological tests and laboratory tasks to investigate possible transfer effects. The results showed significant improvements in the trained group, and no variation in the control group, in processing speed (choice reaction time), attention (reduction of distraction and increase of alertness), immediate and delayed visual recognition memory, as well as a trend to improve in Affection and Assertivity, two dimensions of the Wellbeing Scale. Visuospatial working memory (WM) and executive control (shifting strategy) did not improve. Overall, the current results support the idea that training healthy older adults with non-action video games will enhance some cognitive abilities but not others. PMID:25352805

  2. Brain training with non-action video games enhances aspects of cognition in older adults: a randomized controlled trial.

    PubMed

    Ballesteros, Soledad; Prieto, Antonio; Mayas, Julia; Toril, Pilar; Pita, Carmen; Ponce de León, Laura; Reales, José M; Waterworth, John

    2014-01-01

    Age-related cognitive and brain declines can result in functional deterioration in many cognitive domains, dependency, and dementia. A major goal of aging research is to investigate methods that help to maintain brain health, cognition, independent living and wellbeing in older adults. This randomized controlled study investigated the effects of 20 1-h non-action video game training sessions with games selected from a commercially available package (Lumosity) on a series of age-declined cognitive functions and subjective wellbeing. Two groups of healthy older adults participated in the study, the experimental group who received the training and the control group who attended three meetings with the research team along the study. Groups were similar at baseline on demographics, vocabulary, global cognition, and depression status. All participants were assessed individually before and after the intervention, or a similar period of time, using neuropsychological tests and laboratory tasks to investigate possible transfer effects. The results showed significant improvements in the trained group, and no variation in the control group, in processing speed (choice reaction time), attention (reduction of distraction and increase of alertness), immediate and delayed visual recognition memory, as well as a trend to improve in Affection and Assertivity, two dimensions of the Wellbeing Scale. Visuospatial working memory (WM) and executive control (shifting strategy) did not improve. Overall, the current results support the idea that training healthy older adults with non-action video games will enhance some cognitive abilities but not others. PMID:25352805

  3. Research on energy-saving optimal control of trains in a following operation under a fixed four-aspect autoblock system based on multi-dimension parallel GA

    NASA Astrophysics Data System (ADS)

    Lu, Qiheng; Feng, Xiaoyun

    2013-03-01

    After analyzing the working principle of the four-aspect fixed autoblock system, an energy-saving control model was created based on the dynamics equations of the trains in order to study the energy-saving optimal control strategy of trains in a following operation. Besides the safety and punctuality, the main aims of the model were the energy consumption and the time error. Based on this model, the static and dynamic speed restraints under a four-aspect fixed autoblock system were put forward. The multi-dimension parallel genetic algorithm (GA) and the external punishment function were adopted to solve this problem. By using the real number coding and the strategy of ramps divided into three parts, the convergence of GA was speeded up and the length of chromosomes was shortened. A vector of Gaussian random disturbance with zero mean was superposed to the mutation operator. The simulation result showed that the method could reduce the energy consumption effectively based on safety and punctuality.

  4. Functional Aspects of Gait in Essential Tremor: A Comparison with Age-Matched Parkinsons Disease Cases, Dystonia Cases, and Controls

    PubMed Central

    Louis, Elan D.; Rao, Ashwini K.

    2015-01-01

    Background An understanding of the functional aspects of gait and balance has wide ramifications. Individuals with balance disorders often restrict physical activity, travel, and social commitments to avoid falling, and loss of balance confidence, itself, is a source of disability. We studied the functional aspects of gait in patients with essential tremor (ET), placing their findings within the context of two other neurological disorders (Parkinsons disease [PD] and dystonia) and comparing them with age-matched controls. Methods We administered the six-item Activities of Balance Confidence (ABC-6) Scale and collected data on number of falls and near-falls, and use of walking aids in 422 participants (126 ET, 77 PD, 46 dystonia, 173 controls). Results Balance confidence was lowest in PD, intermediate in ET, and relatively preserved in dystonia compared with controls. This ordering reoccurred for each of the six ABC-6 items. The number of near-falls and falls followed a similar ordering. Use of canes, walkers, and wheelchairs was elevated in ET and even greater in PD. Several measures of balance confidence (ABC-6 items 1, 4, 5, and 6) were lower in torticollis cases than in those with blepharospasm, although the two groups did not differ with respect to falls or use of walking aids. Discussion Lower balance confidence, increased falls, and greater need for walking aids are variably features of a range of movement disorder patients compared to age-matched controls. While most marked among PD patients, these issues affected ET patients as well and, to a small degree, some patients with dystonia. PMID:26056611

  5. Entomological aspects of the first five years of the Onchocerciasis Control Programme in the Volta River Basin.

    PubMed

    Walsh, J F; Davies, J B; Le Berre, R

    1979-09-01

    The history and structure of the WHO Onchocerciasis Control Programme in the Volta River Basin are described. An outline of the vector control operations is given, and the techniques and organisation of the entomological evaluation network are described in detail. During the course of the evaluation and related studies undertaken between November 1974 and October 1978 almost 1.2 million S. damnosum females have been taken in over 52,000 man days of catching, and 674,000 flies were dissected. An assessment based on this effort using Annual Biting Rates and Annual Transmission Potentials shows that the transmission of O. volvulus has been reduced to below a defined maximum permissible level over most of the central part of the Programme Area. The difficulties encountered in the remainder, and at certain problem sites are outlined and relevant data given. The benefits to be expected from extending the area further southwards and the possibilities of later reductions in control activity are discussed. PMID:543001

  6. Urinary Diversions

    PubMed Central

    Davis, Ian

    1991-01-01

    Once the bladder has been removed or declared non-functional, some form of urinary diversion must be performed. The diversion can be as simple as bringing the ureters to the skin and as complicated as the creation of a functioning neobladder. The indications for and expectations of the most common types of diversion are explained. Some new techniques for continent diversion are described. PMID:21229045

  7. Rethinking Diversity.

    ERIC Educational Resources Information Center

    Gordon, Jack

    1992-01-01

    Managing diversity is about coping with unassimilated differences, about building systems and a culture that unite different people in a common pursuit without undermining their diversity. The goal of diversity training is a high performance organization rather than a climate in which no one's feathers are ruffled. (SK)

  8. Metacontrast masking and the cortical representation of surface color: dynamical aspects of edge integration and contrast gain control

    PubMed Central

    Rudd, Michael E.

    2008-01-01

    This paper reviews recent theoretical and experimental work supporting the idea that brightness is computed in a series of neural stages involving edge integration and contrast gain control. It is proposed here that metacontrast and paracontrast masking occur as byproducts of the dynamical properties of these neural mechanisms. The brightness computation model assumes, more specifically, that early visual neurons in the retina, and cortical areas V1 and V2, encode local edge signals whose magnitudes are proportional to the logarithms of the luminance ratios at luminance edges within the retinal image. These local edge signals give rise to secondary neural lightness and darkness spatial induction signals, which are summed at a later stage of cortical processing to produce a neural representation of surface color, or achromatic color, in the case of the chromatically neutral stimuli considered here. Prior to the spatial summation of these edge-based induction signals, the weights assigned to local edge contrast are adjusted by cortical gain mechanisms involving both lateral interactions between neural edge detectors and top-down attentional control. We have previously constructed and computer-simulated a neural model of achromatic color perception based on these principles and have shown that our model gives a good quantitative account of the results of several brightness matching experiments. Adding to this model the realistic dynamical assumptions that 1) the neurons that encode local contrast exhibit transient firing rate enhancement at the onset of an edge, and 2) that the effects of contrast gain control take time to spread between edges, results in a dynamic model of brightness computation that predicts the existence Broca-Sulzer transient brightness enhancement of the target, Type B metacontrast masking, and a form of paracontrast masking in which the target brightness is enhanced when the mask precedes the target in time. PMID:20517518

  9. The interplay of diversity training and diversity beliefs on team creativity in nationality diverse teams.

    PubMed

    Homan, Astrid C; Buengeler, Claudia; Eckhoff, Robert A; van Ginkel, Wendy P; Voelpel, Sven C

    2015-09-01

    Attaining value from nationality diversity requires active diversity management, which organizations often employ in the form of diversity training programs. Interestingly, however, the previously reported effects of diversity training are often weak and, sometimes, even negative. This situation calls for research on the conditions under which diversity training helps or harms teams. We propose that diversity training can increase team creativity, but only for teams with less positive pretraining diversity beliefs (i.e., teams with a greater need for such training) and that are sufficiently diverse in nationality. Comparing the creativity of teams that attended nationality diversity training versus control training, we found that for teams with less positive diversity beliefs, diversity training increased creative performance when the team's nationality diversity was high, but undermined creativity when the team's nationality diversity was low. Diversity training had less impact on teams with more positive diversity beliefs, and training effects were not contingent upon these teams' diversity. Speaking to the underlying process, we showed that these interactive effects were driven by the experienced team efficacy of the team members. We discuss theoretical and practical implications for nationality diversity management. PMID:25688641

  10. Sapogenin content variation in Medicago inter-specific hybrid derivatives highlights some aspects of saponin synthesis and control.

    PubMed

    Carelli, Maria; Biazzi, Elisa; Tava, Aldo; Losini, Ilaria; Abbruscato, Pamela; Depedro, Claudia; Scotti, Carla

    2015-04-01

    In the Medicago genus, saponins are a complex mixture of triterpene glycosides showing a broad spectrum of biological properties. Here we analyzed the variation in the sapogenin content and composition of inter-specific hybrid Medicago sativa × Medicago arborea derivatives to highlight the pattern of this variation in plant organs (leaves/roots) and the possible mechanisms underlying it. In Sativa Arborea Cross (SAC) leaves and roots, saponins and sapogenins were evaluated using chromatographic methods. Phenotypic correlations between sapogenin content and bio-agronomic traits were examined. Expression studies on β-amyrin synthase and four cytochromes P450 (CYPs) involved in sapogenin biosynthesis and sequence analysis of the key gene of the hemolytic sapogenin pathway (CYP716A12) were performed. Chromatographic analyses revealed a different pattern of among-family variation for hemolytic and nonhemolytic sapogenins and saponins and for the two organs/tissues. Different correlation patterns of gene expression in roots and leaves were found. Diachronic analysis revealed a relationship between sapogenin content and gene transcriptional levels in the early stages of the productive cycle. The results suggest that there are different control mechanisms acting on sapogenin biosynthesis for leaves and roots, which are discussed. A key role for medicagenic acid in the control of sapogenin content in both the tissues is proposed and discussed. PMID:25406544

  11. Clinical microbiology of Coxiella burnetii and relevant aspects for the diagnosis and control of the zoonotic disease Q fever.

    PubMed

    Roest, Hendrik I J; Bossers, Alex; van Zijderveld, Fred G; Rebel, Johanna M L

    2013-01-01

    Coxiella burnetii is the causative agent of the zoonotic disease Q fever. Since its first recognition as a disease in the 1930s, the knowledge about the agent and the disease itself has increased. This review summarizes the current knowledge on C. burnetii and Q fever, its pathogenesis, diagnosis and control. C. burnetii is a bacterium which naturally replicates inside human or animal host cells. The clinical presentation of Q fever varies per host species. C. burnetii infection in animals is mainly asymptomatic except for pregnant ruminants in which abortions and stillbirth can occur. In humans, the disease is also mainly asymptomatic, but clinical presentations include acute and chronic Q fever and the post-Q fever fatigue syndrome. Knowledge of the pathogenesis of Q fever in animals and excretion of C. burnetii in infected animals is crucial in understanding the transmission routes and risks of human infection. Our studies indicated that infected pregnant animals only excrete C. burnetii during and after parturition, independent of abortion, and that C. burnetii phase specific serology can be a useful tool in the early detection of infection. Domestic ruminants are the main reservoir for human Q fever, which has a major public health impact when outbreaks occur. In outbreaks, epidemiological source identification can only be refined by genotypic analysis of the strains involved. To control outbreaks and Q fever in domestic ruminants, vaccination with a phase 1 vaccine is effective. Future challenges are to identify factors for virulence, host susceptibility and protection. PMID:24161079

  12. Dose determination and confirmation for ceftiofur crystalline-free acid administered in the posterior aspect of the ear for control and treatment of bovine respiratory disease.

    PubMed

    Hibbard, Beth; Robb, Edward J; Chester, S Theodore; Dame, Kenneth J; Moseley, W William; Bryson, W Lawrence

    2002-01-01

    Three studies were conducted to determine and confirm the effective dosage rate of ceftiofur crystalline-free acid sterile suspension (CCFA-SS, 200 mg ceftiofur equivalents [CE]/ml), a long-acting ceftiofur formulation, for control and treatment of bovine respiratory disease (BRD). In each study, CCFA-SS was administered once by subcutaneous (SC) injection in the middle third of the posterior aspect of the ear. Study 1 was conducted using an intratracheal challenge with Mannheimia (formerly Pasteurella) haemolytica and dosages ranging from 0 to 8.8 mg CE/kg to select a dosage for further field testing. In Study 2, a single dose of CCFA-SS at 0.0, 4.4, or 6.6 mg CE/kg was administered when uniform clinical signs of BRD were present in feedlot cattle. Study 3 was conducted in several feedlots to evaluate the efficacy, practicality, and safety of CCFA-SS at 4.4 or 6.6 mg CE/kg compared with a placebo control or tilmicosin for preemptive control of BRD. In Study 1, the effective dose was determined to be 5.35 mg CE/kg; therefore, 4.4 and 6.6 mg CE/kg were selected as the dosages for further field testing. Administration of CCFA-SS at 4.4 or 6.6 mg CE/kg improved treatment success compared with negative controls (P < or =.05 for both doses) in Study 2. In Study 3, a single administration of 4.4 or 6.6 mg CE/kg was comparable to tilmicosin (P <.001) and was significantly better than placebo (P <.001) for the control of BRD. Using the ear as an administration site was acceptable under field conditions and was well tolerated by all animals. These studies demonstrated that a single administration of CCFA-SS by SC injection in the middle third of the posterior aspect of the ear at 4.4 or 6.6 mg CE/kg is effective, safe, and practical for preemptive control and treatment of the bacterial component of BRD in feedlot cattle. Administration in an inedible tissue results in a short withdrawal time and no injection-site trimming at slaughter. PMID:12050825

  13. From Randomized Controlled Trials of Antidepressant Drugs to the Meta-Analytic Synthesis of Evidence: Methodological Aspects Lead to Discrepant Findings.

    PubMed

    Fountoulakis, Konstantinos N; McIntyre, Roger S; Carvalho, Andr F

    2015-01-01

    During the last decade, several meta-analytic studies employing different methodological approaches have had inconsistent conclusions regarding antidepressant efficacy. Herein, we aim to comment on methodological aspects that may have contributed to disparate findings. We initially discuss methodological inconsistencies and limitations related to the conduct of individual antidepressant randomized controlled trials (RCTs), including differences in allocated samples, limitations of psychometric scales, possible explanations for the heightened placebo response rates in antidepressant RCTs across the past two decades as well as the reporting of conflicts of interest. In the second part of this article, we briefly describe the various meta-analyses techniques (e.g., simple random effects meta-analysis and network meta-analysis) and the application of these methods to synthesize evidence related to antidepressant efficacy. Recently published antidepressant metaanalyses often provide discrepant results and similar results often lead to different interpretations. Finally, we propose strategies to improve methodology considering real-world clinical scenarios. PMID:26467410

  14. From Randomized Controlled Trials of Antidepressant Drugs to the Meta-Analytic Synthesis of Evidence: Methodological Aspects Lead to Discrepant Findings

    PubMed Central

    Fountoulakis, Konstantinos N.; McIntyre, Roger S.; Carvalho, André F.

    2015-01-01

    During the last decade, several meta-analytic studies employing different methodological approaches have had inconsistent conclusions regarding antidepressant efficacy. Herein, we aim to comment on methodological aspects that may have contributed to disparate findings. We initially discuss methodological inconsistencies and limitations related to the conduct of individual antidepressant randomized controlled trials (RCTs), including differences in allocated samples, limitations of psychometric scales, possible explanations for the heightened placebo response rates in antidepressant RCTs across the past two decades as well as the reporting of conflicts of interest. In the second part of this article, we briefly describe the various meta-analyses techniques (e.g., simple random effects meta-analysis and network meta-analysis) and the application of these methods to synthesize evidence related to antidepressant efficacy. Recently published antidepressant metaanalyses often provide discrepant results and similar results often lead to different interpretations. Finally, we propose strategies to improve methodology considering real-world clinical scenarios. PMID:26467410

  15. Aspects of ketogenesis: control and mechanism of ketone-body formation in isolated rat-liver mitochondria.

    PubMed

    Lopes-Cardozo, M; Mulder, I; van Vugt, F; Hermans, P G; van den Bergh, S G; Klazinga, W; de Vries-Akkerman, E

    1975-12-31

    The synthesis of ketone bodies by intact isolated rat-liver mitochondria has been studied at varying rates of acetyl-CoA production and of acetyl-CoA utilization in the Krebs cycle. Factors which enhanced the rate of acetyl-CoA production caused an increase in the fraction of acetyl-CoA which was incorporated into ketone bodies. On the other hand, it was found that factors which stimulated the formation of citrate lowered the relative rate of ketogenesis. It is concluded that acetyl-CoA is preferentially used for citrate synthesis, if the level of oxaloacetate in the mitochondrial matrix space is adequate. The intramitochondrial level of oxaloacetate, which is determined by the malate concentration and the ratio of NADH over NAD+, is the main factor controlling the rate of citrate synthesis. The ATP/ADP ratio per se does not affect the activity of citrate synthase in this in vitro system. Ketogenesis can be described as an overflow of acetyl-groups: Ketone-body formation is stimulated only when the rate of acetyl-CoA production increases beyond the capacity for citrate synthesis. The interaction between fatty acid oxidation and pyruvate metabolism and the effects of long-chain acyl-CoA on mitochondrial metabolism are discussed. Ketone bodies which were generated during the oxidation of [1-14C] fatty acids were preferentially labelled in their carboxyl group. This carboxyl group had the same specific activity as the acetyl-CoA pool, whereas the specific activity of the acetone moiety of acetoacetate was much lower, especially at low rates of ketone-body formation. The activities of acetoacetyl-CoA deacylase and the hydroxymethylglutaryl-CoA (HMG-CoA) pathway were compared in soluble and mitochondrial fractions of rat- and cow-liver in different ketotic states. In rat-liver mitochondria, both pathways of acetoacetate synthesis were stimulated upon starvation or in alloxan diabetes. In cow liver, only the HMG-CoA pathway was increased during ketosis in the mitochondrial as well as in the soluble fraction. PMID:1196305

  16. Topographic Controls on Spatial Patterns of Soil Texture and Moisture in a Semi-arid Montane Catchment with Aspect-Dependent Vegetation

    NASA Astrophysics Data System (ADS)

    Lehman, B. M.; Niemann, J. D.

    2008-12-01

    Soil moisture exerts significant control over the partitioning of latent and sensible energy fluxes, the magnitude of both vertical and lateral water fluxes, the physiological and water-use characteristics of vegetation, and nutrient cycling. Considerable progress has been made in determining how soil characteristics, topography, and vegetation influence spatial patterns of soil moisture in humid environments at the catchment, hillslope, and plant scales. However, understanding of the controls on soil moisture patterns beyond the plant scale in semi-arid environments remains more limited. This study examines the relationships between the spatial patterns of near surface soil moisture (upper 5 cm), terrain indices, and soil properties in a small, semi-arid, montane catchment. The 8 ha catchment, located in the Cache La Poudre River Canyon in north-central Colorado, has a total relief of 115 m and an average elevation of 2193 m. It is characterized by steep slopes and shallow, gravelly/sandy soils with scattered granite outcroppings. Depth to bedrock ranges from 0 m to greater than 1 m. Vegetation in the catchment is highly correlated with topographic aspect. In particular, north-facing hillslopes are predominately vegetated by ponderosa pines, while south-facing slopes are mostly vegetated by several shrub species. Soil samples were collected at a 30 m resolution to characterize soil texture and bulk density, and several datasets consisting of more than 300 point measurements of soil moisture were collected using time domain reflectometry (TDR) between Fall 2007 and Summer 2008 at a 15 m resolution. Results from soil textural analysis performed with sieving and the ASTM standard hydrometer method show that soil texture is finer on the north-facing hillslope than on the south-facing hillslope. Cos(aspect) is the best univariate predictor of silts, while slope is the best predictor of coarser fractions up to fine gravel. Bulk density increases with depth but shows no significant relationship with topographic indices. When the catchment average soil moisture is low, the variance of soil moisture increases with the average. When the average is high, the variance remains relatively constant. Little of the variation in soil moisture is explained by topographic indices when the catchment is either very wet or dry; however, when the average soil moisture takes on intermediate values, cos(aspect) is consistently the best predictor among the terrain indices considered.

  17. High-order myopic coronagraphic phase diversity (COFFEE) for wave-front control in high-contrast imaging systems

    NASA Astrophysics Data System (ADS)

    Paul, B.; Mugnier, L. M.; Sauvage, J.-F.; Ferrari, M.; Dohlen, K.

    2013-12-01

    The estimation and compensation of quasi-static aberrations is mandatory to reach the ultimate performance of high-contrast imaging systems. COFFEE is a focal plane wave-front sensing method that consists in the extension of phase diversity to high-contrast imaging systems. Based on a Bayesian approach, it estimates the quasi-static aberrations from two focal plane images recorded from the scientific camera itself. In this paper, we present COFFEE's extension which allows an estimation of low and high order aberrations with nanometric precision for any coronagraphic device. The performance is evaluated by realistic simulations, performed in the SPHERE instrument framework. We develop a myopic estimation that allows us to take into account an imperfect knowledge on the used diversity phase. Lastly, we evaluate COFFEE's performance in a compensation process, to optimize the contrast on the detector, and show it allows one to reach the 10^-6 contrast required by SPHERE at a few resolution elements from the star. Notably, we present a non-linear energy minimization method which can be used to reach very high contrast levels (better than 10^-7 in a SPHERE-like context)

  18. Contribution of Transcranial Direct Current Stimulation on Inhibitory Control to Assess the Neurobiological Aspects of Attention Deficit Hyperactivity Disorder: Randomized Controlled Trial

    PubMed Central

    Baptista, Abrahão Fontes; de Sena, Eduardo Pondé

    2015-01-01

    Background The applicability of transcranial direct current stimulation (tDCS) in individuals with attention deficit hyperactivity disorder (ADHD) has not yet been investigated. This low-cost, non-invasive, and safe technique optimized to modulate the inhibitory response might be a useful treatment option for those affected by this condition. Objective The aim of this single center, parallel, randomized, double-blinded, sham-controlled trial is to investigate the efficacy of transcranial direct current stimulation over the prefrontal cortex on the modulation of inhibitory control in adults with attention deficit hyperactivity disorder. Methods A total of 60 individuals will be divided into 2 groups by block randomization to receive active or sham stimulation. Anodal stimulation over the left dorsolateral prefrontal cortex will be applied at 1 mA during a single 20-minute session. Before and after interventions, subjects will perform 2 go/no go tasks and the brain electrical activity will be recorded by electroencephalogram (EEG) with 32 channels, according to the 10-20 international EEG system. Results The trial began in May 2013 and we are currently performing the statistical analysis for the secondary outcomes. Conclusions The findings from this study will provide preliminary results about the role of prefrontal cortex activation through tDCS on ADHD patients. Trial Registration Clinicaltrials.gov NCT01968512; http://clinicaltrials.gov/ct2/show/NCT01968512 (Archived by WebCite at www.webcitation.org/6YMSW2tkD). PMID:25986784

  19. Embracing Diversity

    ERIC Educational Resources Information Center

    Roeck, Kathryn T.

    2009-01-01

    The high school art unit "Embracing Diversity" was the author's principal work towards the completion of a Masters thesis. The objective was to learn whether or not teaching an art unit that focused on sexual diversity could have a positive impact on the current culture one finds in high schools. The unit was found to have a positive impact on

  20. Enjoying Diversity

    ERIC Educational Resources Information Center

    Cooper, Renatta; Jones, Elizabeth

    2005-01-01

    Parents and teachers want their children to be safe and to learn the skills they will need to live successful lives in a competitive society. In a diverse and rapidly changing world where people are only an e-mail's blink away from all those strangers everywhere, then it would be safest in the long run to teach young children to "enjoy diversity."

  1. Inhibitory Control in Preschool Predicts Early Math Skills in First Grade: Evidence from an Ethnically Diverse Sample

    ERIC Educational Resources Information Center

    Ng, Florrie Fei-Yin; Tamis-LeMonda, Catherine; Yoshikawa, Hirokazu; Sze, Irene Nga-Lam

    2015-01-01

    Preschoolers' inhibitory control and early math skills were concurrently and longitudinally examined in 255 Chinese, African American, Dominican, and Mexican 4-year-olds in the United States. Inhibitory control at age 4, assessed with a peg-tapping task, was associated with early math skills at age 4 and predicted growth in such skills from

  2. Inhibitory Control in Preschool Predicts Early Math Skills in First Grade: Evidence from an Ethnically Diverse Sample

    ERIC Educational Resources Information Center

    Ng, Florrie Fei-Yin; Tamis-LeMonda, Catherine; Yoshikawa, Hirokazu; Sze, Irene Nga-Lam

    2015-01-01

    Preschoolers' inhibitory control and early math skills were concurrently and longitudinally examined in 255 Chinese, African American, Dominican, and Mexican 4-year-olds in the United States. Inhibitory control at age 4, assessed with a peg-tapping task, was associated with early math skills at age 4 and predicted growth in such skills from…

  3. Comparative studies on the effects of Bt-transgenic and nontransgenic cotton on arthropod diversity, seedcotton yield and bollworms control.

    PubMed

    Dhillon, M K; Sharma, H C

    2013-01-01

    The effectiveness of commercial Bt-cotton in pest management, influence on arthropod diversity, natural enemies, and toxin flow in the insect fauna under field conditions were studied keeping in view the need to assess bioefficacy and biosafety of Bt-transgenic cotton. There were no significant differences in oviposition by Helicoverpa armigera on Bt-transgenic and non-transgenic cottons (9.2 versus 9.6 eggs plants(-100)), while the numbers of H. armigera larvae were significantly more on non-transgenic than on Bt-transgenic (10.4 versus 4.0 larvae plants(-100)) cotton. The Bt-cotton had significantly more number of mature opened bolls (9.6 versus 4.4 bolls plant(-1)), lower bollworm damage (12.8 versus 40.2% bolls damaged), and higher seedcotton yield (667.7 versus 231.7 kg ha 1). Population of cotton leafhopper, Amrasca biguttula biguttula was lower (582.2 versus 732.2 leafhoppers plants(-100)), while that of whitefly, Bemisia tabaci was higher on Bt-transgenic (65.2 versus 45.6 whiteflies plants(-100)) than on non-transgenic cotton. There was no significant influence of Bt-transgenic cotton on abundance of natural enemies of crop pests - chrysopids (9.6 versus 8.4 chrysopids plants(-100), ladybird beetles (16.0 versus 10.8 ladybirds plants(-100)), and spiders (128.4 versus 142.8 spiders plants(-100)). There were no significant differences in H. ormigera egg (19.8 versus 20.9%), larval (7.4 versus 9.6%), and larval-pupal (1.3 versus 2.9%) parasitism on Bt-transgenic and non-transgenic cottons in the farmer's fields. The parasitism in larvae of H. armigera was far lower than that of the eggs, which might be because of early mortality of H. armigera prior to parasitoid development in the host larvae. Although, Cry1Ac Bt toxin was detected in Cheilomenes sexmoculatus, chrysopids, A. bigutulla bigutulla, Thrips taboci, Myllocerus sp., Oxycarenus laetus, Dysdercus koenigii, spiders, bugs, and grasshoppers, no significant differences were observed in their abundance on Bt-transgenic and non-transgenic cottons, suggesting that there were no adverse effects of Bt-cotton on the arthropod diversity under field conditions. PMID:24006809

  4. Towards a better understanding of the relationship between executive control and theory of mind: an intra-cultural comparison of three diverse samples.

    PubMed

    Shahaeian, Ameneh; Henry, Julie D; Razmjoee, Maryam; Teymoori, Ali; Wang, Cen

    2015-09-01

    Previous research has consistently indicated that theory of mind (ToM) is associated with executive control in the preschool years. However, interpretation of this literature is limited by the fact that most studies have focused exclusively on urbanized Western cultural samples. Consequently, it is not clear whether the association between ToM and executive control reflects the specific features of this particular cohort or instead reflects a universal pattern. The present study provides the first empirical assessment of these two constructs in three diverse groups of Iranian children. Participants were 142 preschoolers (4-5 years old) from high-socioeconomic status (SES) urban (n = 33), low-SES urban (n = 37) and rural villages (n = 77). The results show that there is a robust association between ToM and executive control in all three groups, and that executive control contributes significant unique variance to ToM understanding, even after controlling for a range of variables that have been proposed as potential confounders of this relationship. However, although the three groups were equated in ToM, significant differences in executive control were evident. Moreover, cluster analysis identified three distinct clusters that were relatively homogeneous with respect to executive control and SES. One of these clusters was characterized by both low SES and low executive functioning, and showed little evidence of ToM understanding. Taken together, these findings provide possibly the clearest evidence to date that the association between ToM and executive control is not dependent on children's previous experiences on the tasks, or their family and cultural background. PMID:25443564

  5. The Sr1 gene that controls diversity of the anti-inulin antibody response maps to mouse chromosome 14.

    PubMed

    Jones Tiffany, Linda; Riblet, Roy; Stein, Kathryn E

    2003-05-01

    Previous studies demonstrated that the diversity of the antibody response of mice to the inulin (In) determinant of bacterial levan is regulated by the gene Spectrotype Regulation 1 ( Sr1). BALB/c mice produce a monoclonal anti-In response as shown by isoelectric focusing analysis. In contrast, the anti-In antibody response of (BALB/cxC57BL/6)F1 mice is significantly more heterogeneous. We performed a backcross and a genome-wide scan with microsatellite markers and found that Sr1 is tightly linked to D14Mit121 on chromosome (Chr) 14. This location for Sr1 was supported by analysis of CXB Recombinant Inbred strains. We further confirmed this by finding that the Chr 14 congenic mouse strain B6.C-H8 lacks the C57BL/6 allele of the Sr1 gene, indicating that Sr1 is located in the segment of Chr 14 replaced with BALB/c donor DNA. These data place Sr1 near to or coincident with the Tcra/Tcrd T-cell receptor gene complex and suggest a role for T cells in diversifying the anti-In response. PMID:12684850

  6. GABAergic Control of Neurite Outgrowth and Remodeling During Development and Adult Neurogenesis: General Rules and Differences in Diverse Systems

    PubMed Central

    Sernagor, Evelyne; Chabrol, Franois; Bony, Guillaume; Cancedda, Laura

    2010-01-01

    During development, Gamma-aminobutyric acidergic (GABAergic) neurons mature at early stages, long before excitatory neurons. Conversely, GABA reuptake transporters become operative later than glutamate transporters. GABA is therefore not removed efficiently from the extracellular domain and it can exert significant paracrine effects. Hence, GABA-mediated activity is a prominent source of overall neural activity in developing CNS networks, while neurons extend dendrites and axons, and establish synaptic connections. One of the unique features of GABAergic functional plasticity is that in early development, activation of GABAA receptors results in depolarizing (mainly excitatory) responses and Ca2+ influx. Although there is strong evidence from several areas of the CNS that GABA plays a significant role in neurite growth not only during development but also during adult neurogenesis, surprisingly little effort has been made into putting all these observations into a common framework in an attempt to understand the general rules that regulate these basic and evolutionary well-conserved processes. In this review, we discuss the current knowledge in this important field. In order to decipher common, universal features and highlight differences between systems throughout development, we compare findings about dendritic proliferation and remodeling in different areas of the nervous system and species, and we also review recent evidence for a role in axonal elongation. In addition to early developmental aspects, we also consider the GABAergic role in dendritic growth during adult neurogenesis, extending our discussion to the roles played by GABA during dendritic proliferation in early developing networks versus adult, well established networks. PMID:20428495

  7. High aspect ratio nanoimprinted grooves of poly(lactic-co-glycolic acid) control the length and direction of retraction fibers during fibroblast cell division.

    PubMed

    Su, Yi-Hsuan; Chiang, Po-Chieh; Cheng, Li-Jing; Lee, Chau-Hwang; Swami, Nathan S; Chou, Chia-Fu

    2015-01-01

    Retraction fibers (RFs) determine orientation of the cell division axis and guide the spreading of daughter cells. Long and unidirectional RFs, which are especially apparent during mitosis of cells in three-dimensional (3D) environments, enable improved control over cell fate, following division. However, 3D gel environments lack the cues necessary for predetermining the orientation of RFs to direct tissue architecture. While patterning of focal adhesion regions by microcontact printing can determine orientation of the RFs through enhancing focal adhesion numbers along particular directions, the RFs remain short due to the two-dimensional culture environment. Herein, the authors demonstrate that nanoimprinted grooves of polylactic acid glycolic acid (PLGA) with a high aspect ratio (A.R. of 2.0) can provide the cues necessary to control the direction of RFs, as well as enable the maintenance of long and unidirectional RFs as observed within 3D cultures, while the same is not possible with PLGA grooves of lower A.R. (1.0 or lower). Based on enhanced levels of contact guidance of premitotic fibroblast protrusions at high A.R. grooves and deeper levels of focal adhesion due to filopodia extensions into these grooves, it is suggested that submicron (800?nm width) PLGA grooves with A.R. of 2 are capable of supporting mechanical forces from cell protrusions to a greater depth, thereby enabling the maintenance of the protrusions as long and unidirectional RFs during cell division. Given the scalability and versatility of nanoimprint techniques, the authors envision a platform for designing nanostructures to direct tissue regeneration and developmental biology. PMID:26652706

  8. The effect of regular walks on various health aspects in older people with dementia: protocol of a randomized-controlled trial

    PubMed Central

    2011-01-01

    Background Physical activity has proven to be beneficial for physical functioning, cognition, depression, anxiety, rest-activity rhythm, quality of life (QoL), activities of daily living (ADL) and pain in older people. The aim of this study is to investigate the effect of walking regularly on physical functioning, the progressive cognitive decline, level of depression, anxiety, rest-activity rhythm, QoL, ADL and pain in older people with dementia. Methods/design This study is a longitudinal randomized controlled, single blind study. Ambulatory older people with dementia, who are regular visitors of daily care or living in a home for the elderly or nursing home in the Netherlands, will be randomly allocated to the experimental or control condition. Participants of the experimental group make supervised walks of 30 minutes a day, 5 days a week, as part of their daily nursing care. Participants of the control group will come together three times a week for tea or other sedentary activities to control for possible positive effects of social interaction. All dependent variables will be assessed at baseline and after 6 weeks, and 3, 6, 9, 12 and 18 months of intervention. The dependent variables include neuropsychological tests to assess cognition, physical tests to determine physical functioning, questionnaires to assess ADL, QoL, level of depression and anxiety, actigraphy to assess rest-activity rhythm and pain scales to determine pain levels. Potential moderating variables at baseline are: socio-demographic characteristics, body mass index, subtype of dementia, apolipoprotein E (ApoE) genotype, medication use and comorbidities. Discussion This study evaluates the effect of regular walking as a treatment for older people with dementia. The strength of this study is that 1) it has a longitudinal design with multiple repeated measurements, 2) we assess many different health aspects, 3) the intervention is not performed by research staff, but by nursing staff which enables it to become a routine in usual care. Possible limitations of the study are that 1) only active minded institutions are willing to participate creating a selection bias, 2) the drop-out rate will be high in this population, 3) not all participants will be able to perform/understand all tests. Trial registration NTR1482 PMID:21827648

  9. Environmental controls on the distribution and diversity of lentic Chironomidae (Insecta: Diptera) across an altitudinal gradient in tropical South America.

    PubMed

    Matthews-Bird, Frazer; Gosling, William D; Coe, Angela L; Bush, Mark; Mayle, Francis E; Axford, Yarrow; Brooks, Stephen J

    2016-01-01

    To predict the response of aquatic ecosystems to future global climate change, data on the ecology and distribution of keystone groups in freshwater ecosystems are needed. In contrast to mid- and high-latitude zones, such data are scarce across tropical South America (Neotropics). We present the distribution and diversity of chironomid species using surface sediments of 59 lakes from the Andes to the Amazon (0.1-17S and 64-78W) within the Neotropics. We assess the spatial variation in community assemblages and identify the key variables influencing the distributional patterns. The relationships between environmental variables (pH, conductivity, depth, and sediment organic content), climatic data, and chironomid assemblages were assessed using multivariate statistics (detrended correspondence analysis and canonical correspondence analysis). Climatic parameters (temperature and precipitation) were most significant in describing the variance in chironomid assemblages. Temperature and precipitation are both predicted to change under future climate change scenarios in the tropical Andes. Our findings suggest taxa of Orthocladiinae, which show a preference to cold high-elevation oligotrophic lakes, will likely see range contraction under future anthropogenic-induced climate change. Taxa abundant in areas of high precipitation, such as Micropsectra and Phaenopsectra, will likely become restricted to the inner tropical Andes, as the outer tropical Andes become drier. The sensitivity of chironomids to climate parameters makes them important bio-indicators of regional climate change in the Neotropics. Furthermore, the distribution of chironomid taxa presented here is a vital first step toward providing urgently needed autecological data for interpreting fossil chironomid records of past ecological and climate change from the tropical Andes. PMID:26811777

  10. Diversity in Control and Management Techniques for Cactoblastis cactorum and Its Response in its Adventive North American Range

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The South American cactus moth, Cactoblastis cactorum (Berg) (Lepidoptera: Pyralidae), is celebrated for its role as a biological control agent for weedy Opuntia spp. However, multiple unintentional arrivals of C. cactorum in North America represent an economical and ecological threat to native Opun...

  11. Mitochondrial DNA control region diversity and population structure of Pacific herring ( Clupea pallasii) in the Yellow Sea and the Sea of Japan

    NASA Astrophysics Data System (ADS)

    Liu, Ming; Gao, Tianxia; Sakurai, Yasunori; Jia, Ning; Zhao, Linlin; Du, Xiao; Jiang, Qun; Lu, Zhichuan

    2011-03-01

    To investigate the genetic variation and population structure of Pacific herring in the Yellow Sea and the genetic differentiation between the Yellow Sea and the Sea of Japan, fragments of 479-bp mitochondrial DNA control region were sequenced for 110 individuals collected from three different periods in the Yellow Sea and one locality in the Sea of Japan. High haplotype diversity and moderate nucleotide diversity were observed in Pacific herring. AMOVA and exact test of population differentiation showed no significant genetic differentiations among the three populations of the Yellow Sea and suggested the populations can be treated as a single panmictic stock in the Yellow Sea. However, a large and significant genetic differentiation ( ? ST=0.11; P=0.00) was detected between the populations in the Yellow Sea and the Sea of Japan. The high sea water temperature in the Tsushima Strait was thought a barrier to block the gene exchange between populations of the two sea areas. The neutrality tests and mismatch distribution indicated recent population expansion in Pacific herring.

  12. Exploiting the genetic diversity of Beauveria bassiana for improving the biological control of the coffee berry borer through the use of strain mixtures.

    PubMed

    Cruz, Lina P; Gaitan, Alvaro L; Gongora, Carmenza E

    2006-08-01

    Beauveria bassiana is an entomopathogen widely used to control the coffee berry borer in Colombia, as part of an Integrated Pest Management strategy. Traditionally, the development of fungal insect pathogens as biocontrol agents in crop pests has been oriented towards the selection and formulation of elite clonal strains. Instead, we explored the potential application of genetic diversity in B. bassiana by determining the effect of strain mixtures on coffee berry borer mortality compared to clonal isolates. Genomic DNA from 11 strains was characterized using internal transcribed spacers and beta-tubulin sequences as well as amplified fragment length polymorphism markers. Cluster analysis produced three genetic groups and confirmed the low but significant intraspecific genetic diversity present among the strains. Single strain virulence towards the coffee berry borer under laboratory conditions, using 1x10(6) conidia ml(-1), ranged between 89.9 and 57.5%. All the inoculations with mixtures resulted in coinfection events. Combinations of genetically similar strains showed no significant differences when their virulences were compared. However, mixtures of genetically different strains led to both antagonism and synergism. The lowest virulence percentage (57%) was obtained by putting together the most virulent strain of each group, contrary to the highest virulence percentage (93%) that resulted from mixing the three least virulent strains. The results indicate the promising potential of designing strain mixtures as an alternative for the biocontrol of Hypothenemus hampei and other pests and provide tools for the understanding of the ecological dynamics of entomopathogen populations under natural conditions. PMID:16362818

  13. Bioengineering applied to erosion and stability control in the North Apennines (Emilia-Romagna Region, Italy): a check about critical aspects of the works.

    NASA Astrophysics Data System (ADS)

    Selli, Lavinia; Cavazza, Claudio; Pavanelli, Donatella

    2013-04-01

    Because of its geological structure, in the Emilia-Romagna Region over 32,000 landslides have been identified. Several works have been made in order to control mass movement's dynamics and to secure of Reno and Lamone Mountain Basin Rivers, the road network and near by villages and towns. Most of the control works dealt with bioengineering practices: palisades piles, geotextiles, seedings, surface flow control works, dikes within main drainage ditches. In order to check about critical aspects related to the use of these techniques in the Apennines, a survey in this basins was designed with specific interest in the several kinds of works realised, in which plant species were mostly used and in the factors that affected the success or failure of the works. Territory encompasses steep slopes covered with woods to low reliefs covered with grasslands. It is characterized by prevailing clays, inducing instability, and arenaceous lithology with impermeable soils; drainage density is quite high and hillsides suffer extensive and severe erosion and slope stability problems. Chestnut woods mainly represent land use at higher altitudes, while coppice, pastures and crops are present on milder hillsides. The remaining part of the basin is covered by vineyards, orchards, ponds and urban areas, which are basically located in the valley floor. Precipitation events mainly consist of rainfall ranging between 950-1015 mm per year; few snowfalls occur during winter and a long dry season lasts from June until September. We have analyzed 187 works designed mainly for the consolidation of slope instabilities through a widespread enhancement of the vegetation cover. The surveyed works are classified as a function of their building features: it can be seen that cribwalls and palisades are by far the most common types, being the 24% and the 34% respectively of the works. As far as the most adopted plant species, they were silver willow (Salix alba), Spanish Broom (Spartium Junceum) and purple willow (Salix purpurea). Only the 25% of the interventions was accomplished by the use of secondary plant species, as tamarisk (Tamarix spp.,) blackthorn (Prunus spinosa) , whitethorn (Crataegus spp.), sea-buckthorn (Hipphopae rhamnoides), wild pear (Pyrus pyraster), cottonwood (Populus nigra), eglantine (Rosa spp.), goat-willow (Salix caprea) and cornel (Cornus sanguinea). Better results were achieved with Spanish Broom, a very rural plant that can effectively colonise even poor soils like badlands; as a matter of fact, more than the 75% of the interventions had positive outcomes The efficacy of the consolidation work by the presence of living structures point out an increase of the stability of those interventions older than 4 years, with taking root species present from 54% to 78%. So far, the construction and the reliability of the works have been monitored, in order to capture critical aspects for the success of works and to build a geo-referenced data base of the existing works and their status.

  14. Short Communication: p21/CDKN1A Expression Shows Broad Interindividual Diversity in a Subset of HIV-1 Elite Controllers.

    PubMed

    de Pablo, Alicia; Bogoi, Roberta; Bejarano, Irene; Toro, Carlos; Valencia, Eulalia; Moreno, Victoria; Martn-Carbonero, Luz; Gmez-Hernando, Csar; Rods, Berta

    2016-03-01

    The p21/CDKN1A protein has been described in vitro as well as in a small subset of patients as a restriction factor for HIV infection. We evaluated p21/CDKN1A mRNA expression on CD4(+) T cells from HIV-infected individuals with two outcomes (18 elite controllers and 28 viremic progressors). Our results show broad interindividual variation in this factor, which is unrelated to the patient's phenotype. Considering the gene's genetic surroundings in chromosome 6, such as HLA genotype and single nucleotide polymorphisms (SNPs), there was a positive association with carrying HLA-B2705 alleles and the rs733590 SNP. Thus, this natural variation of p21/CDKN1A alone does not appear to be a prognostic indicator of effective viral control in vivo and other factors must be considered. PMID:26537458

  15. Factors Controlling Soil Microbial Biomass and Bacterial Diversity and Community Composition in a Cold Desert Ecosystem: Role of Geographic Scale

    PubMed Central

    Van Horn, David J.; Van Horn, M. Lee; Barrett, John E.; Gooseff, Michael N.; Altrichter, Adam E.; Geyer, Kevin M.; Zeglin, Lydia H.; Takacs-Vesbach, Cristina D.

    2013-01-01

    Understanding controls over the distribution of soil bacteria is a fundamental step toward describing soil ecosystems, understanding their functional capabilities, and predicting their responses to environmental change. This study investigated the controls on the biomass, species richness, and community structure and composition of soil bacterial communities in the McMurdo Dry Valleys, Antarctica, at local and regional scales. The goals of the study were to describe the relationships between abiotic characteristics and soil bacteria in this unique, microbially dominated environment, and to test the scale dependence of these relationships in a low complexity ecosystem. Samples were collected from dry mineral soils associated with snow patches, which are a significant source of water in this desert environment, at six sites located in the major basins of the Taylor and Wright Valleys. Samples were analyzed for a suite of characteristics including soil moisture, pH, electrical conductivity, soil organic matter, major nutrients and ions, microbial biomass, 16 S rRNA gene richness, and bacterial community structure and composition. Snow patches created local biogeochemical gradients while inter-basin comparisons encompassed landscape scale gradients enabling comparisons of microbial controls at two distinct spatial scales. At the organic carbon rich, mesic, low elevation sites Acidobacteria and Actinobacteria were prevalent, while Firmicutes and Proteobacteria were dominant at the high elevation, low moisture and biomass sites. Microbial parameters were significantly related with soil water content and edaphic characteristics including soil pH, organic matter, and sulfate. However, the magnitude and even the direction of these relationships varied across basins and the application of mixed effects models revealed evidence of significant contextual effects at local and regional scales. The results highlight the importance of the geographic scale of sampling when determining the controls on soil microbial community characteristics. PMID:23824063

  16. Genetic diversity and origin of Gayal and cattle in Yunnan revealed by mtDNA control region and SRY gene sequence variation.

    PubMed

    Gou, X; Wang, Y; Yang, S; Deng, W; Mao, H

    2010-04-01

    There are hump, humpless cattle and gayal distributed in Yunnan province, south-west China, but their genetic background remains unclear. To determine the origin and genetic diversity of Yunnan gayal and cattle (Diqing, Nujiang and Wenshan cattle), we analysed mtDNA control region sequences of 71 samples and SRY gene sequences of 39 samples, together with the available sequences in GenBank. The neighbour-joining phylogeny and the reduced median network analysis showed that Yunnan gayal originated from the hybridization between male Bos frontalis and female Bos taurus or Bos indicus, and that Yunnan cattle mostly originated from B. indicus, also containing some hybrids of male B. indicus and female B. taurus. The phylogenetic pattern of Yunnan cattle was consistent with the recently described cattle matrilineal pool from China and indicated more contribution to the Yunnan cattle from B. indicus than from B. taurus. PMID:20433524

  17. The Academy for Future Science Faculty: randomized controlled trial of theory-driven coaching to shape development and diversity of early-career scientists

    PubMed Central

    2014-01-01

    Background Approaches to training biomedical scientists have created a talented research community. However, they have failed to create a professional workforce that includes many racial and ethnic minorities and women in proportion to their representation in the population or in PhD training. This is particularly true at the faculty level. Explanations for the absence of diversity in faculty ranks can be found in social science theories that reveal processes by which individuals develop identities, experiences, and skills required to be seen as legitimate within the profession. Methods/Design Using the social science theories of Communities of Practice, Social Cognitive Career Theory, identity formation, and cultural capital, we have developed and are testing a novel coaching-based model to address some of the limitations of previous diversity approaches. This coaching intervention (The Academy for Future Science Faculty) includes annual in-person meetings of students and trained faculty Career Coaches, along with ongoing virtual coaching, group meetings and communication. The model is being tested as a randomized controlled trial with two cohorts of biomedical PhD students from across the U.S., one recruited at the start of their PhDs and one nearing completion. Stratification into the experimental and control groups, and to coaching groups within the experimental arms, achieved equal numbers of students by race, ethnicity and gender to the extent possible. A fundamental design element of the Academy is to teach and make visible the social science principles which highly influence scientific advancement, as well as acknowledging the extra challenges faced by underrepresented groups working to be seen as legitimate within the scientific communities. Discussion The strategy being tested is based upon a novel application of the well-established principles of deploying highly skilled coaches, selected and trained for their ability to develop talents of others. This coaching model is intended to be a complement, rather than a substitute, for traditional mentoring in biomedical research training, and is being tested as such. PMID:25084625

  18. Drug diversion

    PubMed Central

    Wood, Danielle

    2015-01-01

    SUMMARY Prescription drug diversion has significant health, legal and social implications. Deaths from misuse of prescription drugs account for a significant proportion of overdose deaths. The drugs most commonly involved are analgesics, particularly opioids, and psychoactive drugs, particularly benzodiazepines. Diverted drugs are most often sourced from a family member or friend, but are also sourced from overseas pharmacies or laboratories, or bought from drug dealers. Drug diversion can be mitigated by good prescribing practices. Systems for monitoring the prescribing and dispensing of medicines are being instituted across Australia. PMID:26648654

  19. Drug diversion.

    PubMed

    Wood, Danielle

    2015-10-01

    Prescription drug diversion has significant health, legal and social implications. Deaths from misuse of prescription drugs account for a significant proportion of overdose deaths. The drugs most commonly involved are analgesics, particularly opioids, and psychoactive drugs, particularly benzodiazepines. Diverted drugs are most often sourced from a family member or friend, but are also sourced from overseas pharmacies or laboratories, or bought from drug dealers. Drug diversion can be mitigated by good prescribing practices. Systems for monitoring the prescribing and dispensing of medicines are being instituted across Australia. PMID:26648654

  20. A Personalized and Control Systems Engineering Conceptual Approach to Target Childhood Anxiety in the Contexts of Cultural Diversity

    PubMed Central

    Pina, Armando A.; Holly, Lindsay E.; Zerr, Argero A.; Rivera, Daniel E.

    2014-01-01

    In the child and adolescent anxiety area, some progress has been made to develop evidence-based prevention protocols but less is known about how to best target these problems in children and families of color. In general, data show differential program effects with some minority children benefiting significantly less. Our preliminary data, however, show promise and suggest cultural parameters to consider in the tailoring process beyond language and cultural symbols. It appears that a more focused approach to culture might help activate intervention components and its intended effects by focusing, for example, on the various facets of familismo when working with some Mexican parents. However, testing the effects and nuances of cultural adaption vis-à-vis a focused personalized approach is methodologically challenging. For this reason, we identify control systems engineering design methods and provide example scenarios relevant to our data and recent intervention work. PMID:24702279

  1. Comprehensive Definition of the SigH Regulon of Mycobacterium tuberculosis Reveals Transcriptional Control of Diverse Stress Responses

    PubMed Central

    Park, Sang Tae; Lyubetskaya, Anna; Peterson, Matthew W.; Gomes, Antonio L. C.; Potluri, Lakshmi-Prasad; Raman, Sahadevan; Galagan, James E.; Husson, Robert N.

    2016-01-01

    Expression of SigH, one of 12 Mycobacterium tuberculosis alternative sigma factors, is induced by heat, oxidative and nitric oxide stresses. SigH activation has been shown to increase expression of several genes, including genes involved in maintaining redox equilibrium and in protein degradation. However, few of these are known to be directly regulated by SigH. The goal of this project is to comprehensively define the Mycobacterium tuberculosis genes and operons that are directly controlled by SigH in order to gain insight into the role of SigH in regulating M. tuberculosis physiology. We used ChIP-Seq to identify in vivo SigH binding sites throughout the M. tuberculosis genome, followed by quantification of SigH-dependent expression of genes linked to these sites and identification of SigH-regulated promoters. We identified 69 SigH binding sites, which are located both in intergenic regions and within annotated coding sequences in the annotated M. tuberculosis genome. 41 binding sites were linked to genes that showed greater expression following heat stress in a SigH-dependent manner. We identified several genes not previously known to be regulated by SigH, including genes involved in DNA repair, cysteine biosynthesis, translation, and genes of unknown function. Experimental and computational analysis of SigH-regulated promoter sequences within these binding sites identified strong consensus -35 and -10 promoter sequences, but with tolerance for non-consensus bases at specific positions. This comprehensive identification and validation of SigH-regulated genes demonstrates an extended SigH regulon that controls an unexpectedly broad range of stress response functions. PMID:27003599

  2. Cycles in fossil diversity

    SciTech Connect

    Rohde, Robert A.; Muller, Richard A.

    2004-10-20

    It is well-known that the diversity of life appears to fluctuate during the course the Phanerozoic, the eon during which hard shells and skeletons left abundant fossils (0-542 Ma). Using Sepkoski's compendium of the first and last stratigraphic appearances of 36380 marine genera, we report a strong 62 {+-} 3 Myr cycle, which is particularly strong in the shorter-lived genera. The five great extinctions enumerated by Raup and Sepkoski may be an aspect of this cycle. Because of the high statistical significance, we also consider contributing environmental factors and possible causes.

  3. Diversity's Calling

    ERIC Educational Resources Information Center

    Cooper, Kenneth J.

    2011-01-01

    This article discusses how a Harvard-educated scholar of English and poetry, Dr. M. Lee Pelton puts a prominent face on changes that are underway at Boston's Emerson College. Faced with a public controversy over its limited faculty diversity, Emerson College has responded with a spate of hirings and promotions of minorities, capped by the…

  4. Discovering Diversity.

    ERIC Educational Resources Information Center

    Manner, Barbara M.; Hattler, Jean Anne

    2000-01-01

    Introduces a preservice teacher field trip to the rain forests and coastal areas. This experience develops an awareness for different cultures among preservice teachers by experiencing biological and cultural diversity in Costa Rica. Presents students' own ideas on this experience. (YDS)

  5. Diversity challenge.

    PubMed

    Caudle, Heather

    2015-11-25

    At the chief nursing officer (CNO) for England's summit next week, I will be speaking during a session on developing and retaining the best staff. My contribution will be around the diversity of the nursing and midwifery workforce and the barriers black and minority ethnic (BME) staff face in their careers. PMID:26602658

  6. PLANT DIVERSITY

    EPA Science Inventory

    Habitat change statistics and species-area curves were used to estimate the effects of alternative future scenarios for agriculture on plant diversity in Iowa farmlands. Study areas were two watersheds in central Iowa of about 50 and 90 square kilometers, respectively. Future s...

  7. Diversity Trailblazer

    ERIC Educational Resources Information Center

    Stuart, Reginald

    2012-01-01

    When Dr. Kumea Shorter-Gooden took on her newly created job this month at the University of Maryland's flagship College Park campus, she assumed a challenge at the school with a lot riding on her shoulders--helping the University of Maryland strengthen its diversity efforts and, thus, its relevance to the state in the future and standing among the…

  8. Diversity Trailblazer

    ERIC Educational Resources Information Center

    Stuart, Reginald

    2012-01-01

    When Dr. Kumea Shorter-Gooden took on her newly created job this month at the University of Maryland's flagship College Park campus, she assumed a challenge at the school with a lot riding on her shoulders--helping the University of Maryland strengthen its diversity efforts and, thus, its relevance to the state in the future and standing among the

  9. Controls on the Entrainment of Juvenile Chinook Salmon (Oncorhynchus tshawytscha) into Large Water Diversions and Estimates of Population-Level Loss

    PubMed Central

    Zeug, Steven C.; Cavallo, Bradley J.

    2014-01-01

    Diversion of freshwater can cause significant changes in hydrologic dynamics and this can have negative consequences for fish populations. Additionally, fishes can be directly entrained into diversion infrastructure (e.g. canals, reservoirs, pumps) where they may become lost to the population. However, the effect of diversion losses on fish population dynamics remains unclear. We used 15 years of release and recovery data from coded-wire-tagged juvenile Chinook Salmon (Oncorhynchus tshawytscha) to model the physical, hydrological and biological predictors of salvage at two large water diversions in the San Francisco Estuary. Additionally, entrainment rates were combined with estimates of mortality during migration to quantify the proportion of total mortality that could be attributed to diversions. Statistical modeling revealed a strong positive relationship between diversion rate and fish entrainment at both diversions and all release locations. Other significant relationships were specific to the rivers where the fish were released, and the specific diversion facility. Although significant relationships were identified in statistical models, entrainment loss and the mean contribution of entrainment to total migration mortality were low. The greatest entrainment mortality occurred for fish released along routes that passed closest to the diversions and certain runs of Chinook Salmon released in the Sacramento River suffered greater mortality but only at the highest diversion rates observed during the study. These results suggest losses at diversions should be put into a population context in order to best inform effective management of Chinook Salmon populations. PMID:25019205

  10. Subsoil heterogeneities controlling porewater contaminant mass and microbial diversity at a site with a complex pollution history.

    PubMed

    Puigserver, Diana; Carmona, Jos M; Corts, Amparo; Viladevall, Manuel; Nieto, Jos M; Grifoll, Magdalena; Vila, Joaquim; Parker, Beth L

    2013-01-01

    This study seeks to improve our understanding of the conceptual model of pollutant transport and fate in cases of DNAPL contamination at sites with a complex contamination history. The study was carried out in an unconfined aquifer of alluvial fans in the Tarragona Petrochemical Complex (Spain). Two boreholes were drilled and continuous cores were recovered in order to carry out a detailed core description at centimeter scale and a comprehensive sampling of borehole cores. The biogeochemical heterogeneity at these sites is controlled by the conjunction of lithological, hydrochemical and microbiological heterogeneities. Biodegradation processes of contaminant compounds take place not only at the level of the dissolved fraction in the aquifer but also at the level of the fraction retained in the fine, less conductive materials as shown by the biodegradation haloes of parent and metabolite compounds. Sampling the low-conductivity levels also allowed us to identify compounds, e.g. BTEX, that are the remaining traces of the passage of old contaminant plumes whose sources no longer exist. This enabled us to describe past biogeochemical processes and to partially account for the processes occurring today. Transition zones, characterized by numerous textural changes, constitute ecotones whose biostimulation could be effective in promoting the acceleration of the remediation of the multiple pollution at these sites. PMID:23149156

  11. Conformational diversity of flexible ligand in metal-organic frameworks controlled by size-matching mixed ligands

    NASA Astrophysics Data System (ADS)

    Hua, Xiu-Ni; Qin, Lan; Yan, Xiao-Zhi; Yu, Lei; Xie, Yi-Xin; Han, Lei

    2015-12-01

    Hydrothermal reactions of N-auxiliary flexible exo-bidentate ligand 1,3-bis(4-pyridyl)propane (bpp) and carboxylates ligands naphthalene-2,6-dicarboxylic acid (2,6-H2ndc) or 4,4‧-(hydroxymethylene)dibenzoic acid (H2hmdb), in the presence of cadmium(II) salts have given rise to two novel metal-organic frameworks based on flexible ligands (FL-MOFs), namely, [Cd2(2,6-ndc)2(bpp)(DMF)]·2DMF (1) and [Cd3(hmdb)3(bpp)]·2DMF·2EtOH (2) (DMF=N,N-Dimethylformamide). Single-crystal X-ray diffraction analyses revealed that compound 1 exhibits a three-dimensional self-penetrating 6-connected framework based on dinuclear cluster second building unit. Compound 2 displays an infinite three-dimensional 'Lucky Clover' shape (2,10)-connected network based on the trinuclear cluster and V-shaped organic linkers. The flexible bpp ligand displays different conformations in 1 and 2, which are successfully controlled by size-matching mixed ligands during the self-assembly process.

  12. Adapting Standardized Content to Diverse Students.

    ERIC Educational Resources Information Center

    Morrison, Veronica Kraly

    This packet of materials is designed to aid teachers in redesigning their courses to accommodate diverse students. The worksheets help organize information on what aspects of diversity are present in each class, what course elements can and cannot be adapted to them, and how these adaptations might be implemented. The worksheets, along with the

  13. Leadership and Diversity: Theory and Research

    ERIC Educational Resources Information Center

    Lumby, Jacky; Morrison, Marlene

    2010-01-01

    Diversity has become a ubiquitous term within education, often harnessed with a second concept, that of inclusion. Despite heightened interest, theorists in education leadership have remained relatively uninterested in multiple aspects of identity and diversity. This article explores the epistemological and methodological implications of moving

  14. Effects of N-glycan precursor length diversity on quality control of protein folding and on protein glycosylation.

    PubMed

    Samuelson, John; Robbins, Phillips W

    2015-05-01

    Asparagine-linked glycans (N-glycans) of medically important protists have much to tell us about the evolution of N-glycosylation and of N-glycan-dependent quality control (N-glycan QC) of protein folding in the endoplasmic reticulum. While host N-glycans are built upon a dolichol-pyrophosphate-linked precursor with 14 sugars (Glc3Man9GlcNAc2), protist N-glycan precursors vary from Glc3Man9GlcNAc2 (Acanthamoeba) to Man9GlcNAc2 (Trypanosoma) to Glc3Man5GlcNAc2 (Toxoplasma) to Man5GlcNAc2 (Entamoeba, Trichomonas, and Eimeria) to GlcNAc2 (Plasmodium and Giardia) to zero (Theileria). As related organisms have differing N-glycan lengths (e.g. Toxoplasma, Eimeria, Plasmodium, and Theileria), the present N-glycan variation is based upon secondary loss of Alg genes, which encode enzymes that add sugars to the N-glycan precursor. An N-glycan precursor with Man5GlcNAc2 is necessary but not sufficient for N-glycan QC, which is predicted by the presence of the UDP-glucose:glucosyltransferase (UGGT) plus calreticulin and/or calnexin. As many parasites lack glucose in their N-glycan precursor, UGGT product may be identified by inhibition of glucosidase II. The presence of an armless calnexin in Toxoplasma suggests secondary loss of N-glycan QC from coccidia. Positive selection for N-glycan sites occurs in secreted proteins of organisms with N-glycan QC and is based upon an increased likelihood of threonine but not serine in the +2 position versus asparagine. In contrast, there appears to be selection against N-glycan length in Plasmodium and N-glycan site density in Toxoplasma. Finally, there is suggestive evidence for N-glycan-dependent ERAD in Trichomonas, which glycosylates and degrades the exogenous reporter mutant carboxypeptidase Y (CPY*). PMID:25475176

  15. Treatment of Binge Eating Disorder in Racially and Ethnically Diverse Obese Patients in Primary Care: Randomized Placebo-Controlled Clinical Trial of Self-Help and Medication

    PubMed Central

    Grilo, Carlos M.; Masheb, Robin M.; White, Marney A.; Gueorguieva, Ralitza; Barnes, Rachel D.; Walsh, B. Timothy; McKenzie, Katherine C.; Genao, Inginia; Garcia, Rina

    2014-01-01

    Objective The objective was to determine whether treatments with demonstrated efficacy for binge eating disorder (BED) in specialist treatment centers can be delivered effectively in primary care settings to racially/ethnically diverse obese patients with BED. This study compared the effectiveness of self-help cognitive-behavioral therapy (shCBT) and an anti-obesity medication (sibutramine), alone and in combination, and it is only the second placebo-controlled trial of any medication for BED to evaluate longer-term effects after treatment discontinuation. Method 104 obese patients with BED (73% female, 55% non-white) were randomly assigned to one of four 16-week treatments (balanced 2-by-2 factorial design): sibutramine (N=26), placebo (N=27), shCBT+sibutramine (N=26), or shCBT+placebo (N=25). Medications were administered in double-blind fashion. Independent assessments were performed monthly throughout treatment, post-treatment, and at 6- and 12-month follow-ups (16 months after randomization). Results Mixed-models analyses revealed significant time and medication-by-time interaction effects for percent weight loss, with sibutramine but not placebo associated with significant change over time. Percent weight loss differed significantly between sibutramine and placebo by the third month of treatment and at post-treatment. After the medication was discontinued at post-treatment, weight re-gain occurred in sibutramine groups and percent weight loss no longer differed among the four treatments at 6- and 12-month follow-ups. For binge-eating, mixed-models revealed significant time and shCBT-by-time interaction effects: shCBT had significantly lower binge-eating frequency at 6-month follow-up but the treatments did not differ significantly at any other time point. Demographic factors did not significantly predict or moderate clinical outcomes. Discussion Our findings suggest that pure self-help CBT and sibutramine did not show long-term effectiveness relative to placebo for treating BED in racially/ethnically diverse obese patients in primary care. Overall, the treatments differed little with respect to binge-eating and associated outcomes. Sibutramine was associated with significantly greater acute weight loss than placebo and the observed weight-regain following discontinuation of medication suggests that anti-obesity medications need to be continued for weight loss maintenance. Demographic factors did not predict/moderate clinical outcomes in this diverse patient group. PMID:24857821

  16. Mitochondrial control region I and microsatellite analyses of endangered Philippine hornbill species (Aves; Bucerotidae) detect gene flow between island populations and genetic diversity loss

    PubMed Central

    2012-01-01

    Background The Visayan Tarictic Hornbill (Penelopides panini) and the Walden’s Hornbill (Aceros waldeni) are two threatened hornbill species endemic to the western islands of the Visayas that constitute - between Luzon and Mindanao - the central island group of the Philippine archipelago. In order to evaluate their genetic diversity and to support efforts towards their conservation, we analyzed genetic variation in ~ 600 base pairs (bp) of the mitochondrial control region I and at 12–19 nuclear microsatellite loci. The sampling covered extant populations, still occurring only on two islands (P. panini: Panay and Negros, A. waldeni: only Panay), and it was augmented with museum specimens of extinct populations from neighboring islands. For comparison, their less endangered (= more abundant) sister taxa, the Luzon Tarictic Hornbill (P. manillae) from the Luzon and Polillo Islands and the Writhed Hornbill (A. leucocephalus) from Mindanao Island, were also included in the study. We reconstructed the population history of the two Penelopides species and assessed the genetic population structure of the remaining wild populations in all four species. Results Mitochondrial and nuclear data concordantly show a clear genetic separation according to the island of origin in both Penelopides species, but also unravel sporadic over-water movements between islands. We found evidence that deforestation in the last century influenced these migratory events. Both classes of markers and the comparison to museum specimens reveal a genetic diversity loss in both Visayan hornbill species, P. panini and A. waldeni, as compared to their more abundant relatives. This might have been caused by local extinction of genetically differentiated populations together with the dramatic decline in the abundance of the extant populations. Conclusions We demonstrated a loss in genetic diversity of P. panini and A. waldeni as compared to their sister taxa P. manillae and A. leucocephalus. Because of the low potential for gene flow and population exchange across islands, saving of the remaining birds of almost extinct local populations - be it in the wild or in captivity - is particularly important to preserve the species’ genetic potential. PMID:23057730

  17. Treatment of binge eating disorder in racially and ethnically diverse obese patients in primary care: randomized placebo-controlled clinical trial of self-help and medication.

    PubMed

    Grilo, Carlos M; Masheb, Robin M; White, Marney A; Gueorguieva, Ralitza; Barnes, Rachel D; Walsh, B Timothy; McKenzie, Katherine C; Genao, Inginia; Garcia, Rina

    2014-07-01

    The objective was to determine whether treatments with demonstrated efficacy for binge eating disorder (BED) in specialist treatment centers can be delivered effectively in primary care settings to racially/ethnically diverse obese patients with BED. This study compared the effectiveness of self-help cognitive-behavioral therapy (shCBT) and an anti-obesity medication (sibutramine), alone and in combination, and it is only the second placebo-controlled trial of any medication for BED to evaluate longer-term effects after treatment discontinuation. 104 obese patients with BED (73% female, 55% non-white) were randomly assigned to one of four 16-week treatments (balanced 2-by-2 factorial design): sibutramine (N= 26), placebo (N = 27), shCBT + sibutramine (N = 26), or shCBT + placebo (N = 25). Medications were administered in double-blind fashion. Independent assessments were performed monthly throughout treatment, post-treatment, and at 6- and 12-month follow-ups (16 months after randomization). Mixed-models analyses revealed significant time and medication-by-time interaction effects for percent weight loss, with sibutramine but not placebo associated with significant change over time. Percent weight loss differed significantly between sibutramine and placebo by the third month of treatment and at post-treatment. After the medication was discontinued at post-treatment, weight re-gain occurred in sibutramine groups and percent weight loss no longer differed among the four treatments at 6- and 12-month follow-ups. For binge-eating, mixed-models revealed significant time and shCBT-by-time interaction effects: shCBT had significantly lower binge-eating frequency at 6-month follow-up but the treatments did not differ significantly at any other time point. Demographic factors did not significantly predict or moderate clinical outcomes. Our findings suggest that pure self-help CBT and sibutramine did not show long-term effectiveness relative to placebo for treating BED in racially/ethnically diverse obese patients in primary care. Overall, the treatments differed little with respect to binge-eating and associated outcomes. Sibutramine was associated with significantly greater acute weight loss than placebo and the observed weight-regain following discontinuation of medication suggests that anti-obesity medications need to be continued for weight loss maintenance. Demographic factors did not predict/moderate clinical outcomes in this diverse patient group. PMID:24857821

  18. Diversity of bacteriophages infecting Xanthomonas oryzae pv. oryzae in paddy fields and its potential to control bacterial leaf blight of rice.

    PubMed

    Chae, Jong-Chan; Hung, Nguyen Bao; Yu, Sang-Mi; Lee, Ha Kyung; Lee, Yong Hoon

    2014-06-28

    Bacterial leaf blight (BLB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is a very serious disease in rice-growing regions of the world. In spite of their economic importance, there are no effective ways of protecting rice plants from this disease. Bacteriophages infecting Xoo affect the population dynamics of the pathogen and consequently the occurrence of the disease. In this study, we investigated the diversity, host range, and infectivity of Xoo phages, and their use as a bicontrol agent on BLB was tested. Among the 34 phages that were isolated from floodwater in paddy fields, 29 belonged to the Myoviridae family, which suggests that the dominant phage in the ecosystem was Myoviridae. The isolated phages were classified into two groups based on plaque size produced on the lawn of Xoo. In general, there was a negative relationship between plaque size and host range, and interestingly the phages having a narrow host range had low efficiency of infectivity. The deduced protein sequence analysis of htf genes indicated that the gene was not a determinant of host specificity. Although the difference in host range and infectivity depending on morphotype needs to be addressed, the results revealed deeper understanding of the interaction between the phages and Xoo strains in floodwater and damp soil environments. The phage mixtures reduced the occurrence of BLB when they were treated with skim milk. The results indicate that the Xoo phages could be used as an alternative control method to increase the control efficacy and reduce the use of agrochemicals. PMID:24651644

  19. Supporting Diversity.

    ERIC Educational Resources Information Center

    Horton, Betty, Ed.; And Others

    1996-01-01

    This newsletter feature issue focuses on services for persons with developmental disabilities that support the whole person by acknowledging, respecting, and incorporating aspects of identity such as race, ethnicity, religion, sexual orientation, gender, age, and class. Articles include: (1) "Serving the Whole Person: The Journey to Embracing…

  20. Applying the European protocol for the quality control of the physical and technical aspects of mammography screening threshold contrast visibility assessment to digital systems

    NASA Astrophysics Data System (ADS)

    Van Metter, Richard; Heath, Michael; Fletcher-Heath, Lynn

    2006-03-01

    The need to assure the image quality of digital systems for mammography screening applications is now widely recognized. One approach is embodied in Part B of the European Protocol for the Quality Control of the Physical and Technical Aspects of Mammography Screening (EPQCM), which prescribes criteria for several interconnected image quality metrics. The focus of this study is on the "threshold contrast visibility" (TCV) protocol (section 2.4.1 of the EPQCM), in which human observers score images of a CDMAM or similar 4-AFC phantom. This section of the EPQCM currently omits many critical experimental details, which must be gleaned from ancillary documents. Given these, the purpose of this study is to quantify the effects of several remaining experimental variables, including phantom design, and the methods used for scoring and analysis, on the measured results. Preliminary studies of two CDMAM version 3.4 (CDMAM 3.4) phantoms have revealed a 17% difference in TCV when averaged over all target diameters from 0.1 to 2.0 mm. This indicates phantom variability may affect results at some sites. More importantly, we have shown that the current CDMAM phantom design, methods for scoring, and analysis, substantially limit the ability to measure system performance accurately and precisely. An improved phantom design has been shown to avoid these limitations. Viewing environment and presentation context affect the performance and efficiency of visual scoring of phantom images. An automated display tool has been developed that isolates individual 4-AFC targets of CDMAM phantom images, automatically optimizes window/level, and automatically records observers' scores. While not substantially changing TCV, the tool has increased scoring efficiency while mitigating several of the limitations associated with unassisted visual scoring. For example, learning bias and navigational issues are completely avoided. Ultimately, software-based ideal observer scoring will likely prove to be a better approach. Statistical-decision-theory-based (SDT) analysis has been shown to mitigate limitations associated with the current CDMAM phantom and the ad hoc nearest-neighbor correcting (NNC) scoring method. NNC analysis is sensitive to the degree of incomplete scoring (stopping criteria). However, SDT substantially mitigates this problem, using all of the available data to derive thresholds that are more interpretable. Bootstrap sampling was used to provide an estimate of the standard error for SDT analysis. In conclusion, the current EPQCM section 2.4.1 protocol fails to measure TCV accurately and precisely enough to qualify digital mammography systems. This paper presents a series of recommendations that supplement section 2.4.1 of the EPQCM and that provide a stable and accurate measure of TCV.

  1. Opening the gender diversity black box: causality of perceived gender equity and locus of control and mediation of work engagement in employee well-being

    PubMed Central

    Sharma, Radha R.; Sharma, Neha P.

    2015-01-01

    The study is aimed at assessing the role of perceived gender equity and locus of control in employee well-being at the workplace and ascertaining if work engagement mediates between perceived gender equity, locus of control, and employee well-being (measured through optimism, general satisfaction with life and work, and executive burnout). Adopting a personal survey method data was collected from 373 managers (both males and females) from the public and private sectors representing manufacturing and service industry in India. The study bridges the knowledge gap by operationalizing the construct of perceived gender equity and studying its role in the work engagement and employee well-being. Conceptualization of the well-being in an unconventional way covering both the positive and the negative aspects extends the understanding of the emerging concept of well-being. It has practical implications for talent management and work engagement besides promoting gender equity at the workplace for employee well-being. It opens vistas for the gender based theory and cross cultural research on gender equity. PMID:26500566

  2. Dynamics and control at feedback vertex sets. II: a faithful monitor to determine the diversity of molecular activities in regulatory networks.

    PubMed

    Mochizuki, Atsushi; Fiedler, Bernold; Kurosawa, Gen; Saito, Daisuke

    2013-10-21

    Modern biology provides many networks describing regulations between many species of molecules. It is widely believed that the dynamics of molecular activities based on such regulatory networks are the origin of biological functions. However, we currently have a limited understanding of the relationship between the structure of a regulatory network and its dynamics. In this study we develop a new theory to provide an important aspect of dynamics from information of regulatory linkages alone. We show that the "feedback vertex set" (FVS) of a regulatory network is a set of "determining nodes" of the dynamics. The theory is powerful to study real biological systems in practice. It assures that (i) any long-term dynamical behavior of the whole system, such as steady states, periodic oscillations or quasi-periodic oscillations, can be identified by measurements of a subset of molecules in the network, and that (ii) the subset is determined from the regulatory linkage alone. For example, dynamical attractors possibly generated by a signal transduction network with 113 molecules can be identified by measurement of the activity of only 5 molecules, if the information on the network structure is correct. Our theory therefore provides a rational criterion to select key molecules to control a system. We also demonstrate that controlling the dynamics of the FVS is sufficient to switch the dynamics of the whole system from one attractor to others, distinct from the original. PMID:23774067

  3. Opening the gender diversity black box: causality of perceived gender equity and locus of control and mediation of work engagement in employee well-being.

    PubMed

    Sharma, Radha R; Sharma, Neha P

    2015-01-01

    The study is aimed at assessing the role of perceived gender equity and locus of control in employee well-being at the workplace and ascertaining if work engagement mediates between perceived gender equity, locus of control, and employee well-being (measured through optimism, general satisfaction with life and work, and executive burnout). Adopting a personal survey method data was collected from 373 managers (both males and females) from the public and private sectors representing manufacturing and service industry in India. The study bridges the knowledge gap by operationalizing the construct of perceived gender equity and studying its role in the work engagement and employee well-being. Conceptualization of the well-being in an unconventional way covering both the positive and the negative aspects extends the understanding of the emerging concept of well-being. It has practical implications for talent management and work engagement besides promoting gender equity at the workplace for employee well-being. It opens vistas for the gender based theory and cross cultural research on gender equity. PMID:26500566

  4. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity.

    PubMed

    Hertzog, Lionel R; Meyer, Sebastian T; Weisser, Wolfgang W; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas carnivore communities were affected by forbs of small stature, grasses and legumes. Contrasting patterns in the abundance of dominant species imply different levels of resource specialization for dominant herbivores (narrow food spectrum) and carnivores (broad food spectrum). That in turn could heavily affect ecosystem functions mediated by herbivorous and carnivorous arthropods, such as herbivory or biological pest control. PMID:26859496

  5. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity

    PubMed Central

    Hertzog, Lionel R.; Meyer, Sebastian T.; Weisser, Wolfgang W.; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas carnivore communities were affected by forbs of small stature, grasses and legumes. Contrasting patterns in the abundance of dominant species imply different levels of resource specialization for dominant herbivores (narrow food spectrum) and carnivores (broad food spectrum). That in turn could heavily affect ecosystem functions mediated by herbivorous and carnivorous arthropods, such as herbivory or biological pest control. PMID:26859496

  6. A randomized clinical trial of Cogmed Working Memory Training in school-age children with ADHD: A replication in a diverse sample using a control condition

    PubMed Central

    Chacko, A; Bedard, A. C; Marks, D.J; Feirsen, N; Uderman, J.Z; Chimiklis, A; Rajwan, E; Cornwell, M; Anderson, L; Zwilling, A; Ramon, M

    2013-01-01

    Background Cogmed Working Memory Training (CWMT) has received considerable attention as a promising intervention for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) in children. At the same time, methodological weaknesses in previous clinical trials call into question reported efficacy of CWMT. In particular, lack of equivalence in key aspects of CWMT (i.e., contingent reinforcement, time-on-task with computer training, parent-child interactions, supportive coaching) between CWMT and placebo versions of CWMT used in previous trials may account for the beneficial outcomes favoring CWMT. Methods Eighty-five 7- to 11-year old school-age children with ADHD (66 male; 78%) were randomized to either standard CWMT (CWMT Active) or a well-controlled CWMT placebo condition (CWMT Placebo) and evaluated before and 3 weeks after treatment. Dependent measures included parent and teacher ratings of ADHD symptoms; objective measures of attention, activity level, and impulsivity; and psychometric indices of working memory and academic achievement (Clinical trial title: Combined cognitive remediation and behavioral intervention for the treatment of Attention-Deficit/Hyperactivity Disorder; http://clinicaltrials.gov/ct2/show/NCT01137318). Results CWMT Active participants demonstrated significantly greater improvements in verbal and nonverbal working memory storage, but evidenced no discernible gains in working memory storage plus processing/manipulation. In addition, no treatment group differences were observed for any other outcome measures. Conclusions When a more rigorous comparison condition is utilized, CWMT demonstrates effects on certain aspects of working memory in children with ADHD; however, CWMT does not appear to foster treatment generalization to other domains of functioning. As such, CWMT should not be considered a viable treatment for children with ADHD. PMID:24117656

  7. Relationship between species diversity and ecotope diversity.

    PubMed

    Yue, Tian-Xiang; Li, Qi-Quan

    2010-05-01

    The relationship between species diversity and ecotope diversity has long been debated. But these debates seem meaningless because most of them were based on different definitions. In this paper, diversity has two components: richness based on the total number and evenness based on the relative abundance. Species diversity is distinguished into individual-counting diversity and biomass-based diversity. Ecotope diversity is divided into individual ecotope-counting diversity and ecotope-area based diversity. Under this definition, we make a comprehensive investigation into Dongzhi tableland of Loess Plateau by cooperating with local technicians. We find that individual-counting diversity is significantly correlated with biomass-based diversity in grassland ecosystems; individual ecotope-counting diversity and ecotope-area based diversity have a significant correlation. Therefore, it is unnecessary to divide species diversity into individual-counting diversity and biomass-based diversity in grassland ecosystems and to distinguish ecotope diversity into individual ecotope-counting and ecotope-area based diversity for the issues that have no special requirement for accuracy. But the analyses of the investigation data demonstrate that species diversity has no significant correlation with ecotope diversity. PMID:20586772

  8. What Makes Racial Diversity Work in Higher Education: Academic Leaders Present Successful Policies and Strategies.

    ERIC Educational Resources Information Center

    Hale, Frank W., Jr., Ed.

    The essays in this collection establish the case for racial diversity , outline the challenges diversity offers the academic community, presents examples of how some institutions have developed successful models of diversity, and discusses how the history of racial diversity has influenced aspects of diversity today. Following a foreword,…

  9. What Makes Racial Diversity Work in Higher Education: Academic Leaders Present Successful Policies and Strategies.

    ERIC Educational Resources Information Center

    Hale, Frank W., Jr., Ed.

    The essays in this collection establish the case for racial diversity , outline the challenges diversity offers the academic community, presents examples of how some institutions have developed successful models of diversity, and discusses how the history of racial diversity has influenced aspects of diversity today. Following a foreword,

  10. Valuing Diversity

    PubMed Central

    Fryer, Roland G.; Loury, Glenn C.

    2014-01-01

    This paper explores the economics of diversity-enhancing policies. A model is proposed in which heterogeneous agents, distinguished by skill level and social identity, purchase productive opportunities in a competitive market. We analyze policies designed to raise the status of a disadvantaged identity group. When agent identity is contractible, efficient policy grants preferred access to slots but offers no direct assistance for acquiring skills. When identity is not contractible, efficient policy provides universal subsidies to skill development when the fraction of the disadvantaged group at the skill development margin is larger than their share at the slot assignment margin. PMID:25525280

  11. Effectiveness of Housing First with Intensive Case Management in an Ethnically Diverse Sample of Homeless Adults with Mental Illness: A Randomized Controlled Trial

    PubMed Central

    Stergiopoulos, Vicky; Gozdzik, Agnes; Misir, Vachan; Skosireva, Anna; Connelly, Jo; Sarang, Aseefa; Whisler, Adam; Hwang, Stephen W.; O’Campo, Patricia; McKenzie, Kwame

    2015-01-01

    Housing First (HF) is being widely disseminated in efforts to end homelessness among homeless adults with psychiatric disabilities. This study evaluates the effectiveness of HF with Intensive Case Management (ICM) among ethnically diverse homeless adults in an urban setting. 378 participants were randomized to HF with ICM or treatment-as-usual (TAU) in Toronto (Canada), and followed for 24 months. Measures of effectiveness included housing stability, physical (EQ5D-VAS) and mental (CSI, GAIN-SS) health, social functioning (MCAS), quality of life (QoLI20), and health service use. Two-thirds of the sample (63%) was from racialized groups and half (50%) were born outside Canada. Over the 24 months of follow-up, HF participants spent a significantly greater percentage of time in stable residences compared to TAU participants (75.1% 95% CI 70.5 to 79.7 vs. 39.3% 95% CI 34.3 to 44.2, respectively). Similarly, community functioning (MCAS) improved significantly from baseline in HF compared to TAU participants (change in mean difference = +1.67 95% CI 0.04 to 3.30). There was a significant reduction in the number of days spent experiencing alcohol problems among the HF compared to TAU participants at 24 months (ratio of rate ratios = 0.47 95% CI 0.22 to 0.99) relative to baseline, a reduction of 53%. Although the number of emergency department visits and days in hospital over 24 months did not differ significantly between HF and TAU participants, fewer HF participants compared to TAU participants had 1 or more hospitalizations during this period (70.4% vs. 81.1%, respectively; P=0.044). Compared to non-racialized HF participants, racialized HF participants saw an increase in the amount of money spent on alcohol (change in mean difference = $112.90 95% CI 5.84 to 219.96) and a reduction in physical community integration (ratio of rate ratios = 0.67 95% CI 0.47 to 0.96) from baseline to 24 months. Secondary analyses found a significant reduction in the number of days experiencing problems due to alcohol use among foreign-born (vs. Canadian-born) HF participants at 24 months (ratio of rate ratios = 0.19 95% 0.04 to 0.88), relative to baseline. Compared to usual care, HF with ICM can improve housing stability and community functioning and reduce the days of alcohol related problems in an ethnically diverse sample of homeless adults with mental illness within 2-years. Trial Registration Controlled-Trials.com ISRCTN42520374. PMID:26176621

  12. Comparative Mechanisms of Branching Morphogenesis in Diverse Systems

    PubMed Central

    Lu, Pengfei; Sternlicht, Mark D.; Werb, Zena

    2008-01-01

    Much progress has been made in recent years toward understanding mechanisms controlling branching morphogenesis, a fundamental aspect of development in a variety of invertebrate and vertebrate organs. To gain a deeper understanding of how branching morphogenesis occurs in the mammary gland, we compare and contrast the cellular and molecular events underlying this process in both invertebrate and vertebrate organs. Thus, in this review, we focus on the common themes that have emerged from such comparative analyses and discuss how they are implemented via a battery of signaling pathways to ensure proper branching morphogenesis in diverse systems. PMID:17120154

  13. Pd-catalyzed intramolecular C-N bond cleavage, 1,4-migration, sp3 C-H activation, and Heck reaction: four controllable diverse pathways depending on the judicious choice of the base and ligand.

    PubMed

    Wang, Min; Zhang, Xiang; Zhuang, Yu-Xuan; Xu, Yun-He; Loh, Teck-Peng

    2015-01-28

    Diverse and controllable pathways induced by palladium-catalyzed intramolecular Heck reaction of N-vinylacetamides for the synthesis of nitrogen-containing products in reasonable to high yields via tuning the phosphine ligands and bases are reported. Domino reactions including unique ?-N-Pd elimination, 1,4-Pd migration, or direct acyl C-H bond functionalization were found to be involved forming different products, respectively. Given the ability of using the same starting material to generate diverse products via completely different chemoselective processes, these current methodologies offer straightforward access to valuable nitrogen-containing products under mild reaction conditions as well as inspire the discovery of novel reactions. PMID:25545361

  14. Postmenopausal osteoporosis: microradiographic aspects.

    PubMed

    Dhem, A; Nyssen-Behets, C; Coppens, J

    1998-01-01

    A comparative microradiographic and histologic analysis of undecalcified bone samples was performed in men and women aged 18-98 years. These morphological methods showed that besides usual lamellar bone remodelling, all the so-called inert surfaces, namely both haversian and vascular canals as well as trabecular surfaces, were involved in weathering alterations of the superficial lamellae, resulting in eroded outlines devoid of osteoclast. These aspects, recorded in all pieces of our material, were visible from the earliest adult age and were randomly distributed. Except the grade of osteoporosis at a given age, the microradiographic and histologic aspects were similar in both aged men and women and did not allow sex distinction. These observations were consistent with the hypothesis of a particular destructive process affecting all the quiescent lamellar bone surfaces without osteoclast or cell participation. This kind of erosion, termed delitescence, could be at least partially responsible for the age-related and postmenopausal bone loss. In order to explain the increasing osteoporosis after menopause, it has been suggested that the estrogen deficiency could increase the percentage of dead osteocytes. Thereby the reduced cellular control on the bone surface could impair the remodeling process and fail to adapt the bone structure by repairing the microscopic lesions. PMID:11315966

  15. BOVINE VIRAL DIARRHEA VIRUS ANTIGENIC DIVERSITY: IMPACT ON DISEASE AND VACCINATION PROGRAMS (DETECTING AND CONTROLLING BVDV INFECTIONS, 4/4-5/02, AMES, IA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bovine viral diarrhea virus (BVDV) infections in cattle are associated with a variety or "diverse" clinical forms. These include digestive tract disease, respiratory disease, fetal diseases (varied, dependent on fetal age), systemic disease such as mucosal disease, immunosuppression, hemorrhagic di...

  16. Genetic diversity and population structure of yellow catfish Pelteobagrus fulvidraco from five lakes in the middle and lower reaches of the Yangtze River, China, based on mitochondrial DNA control region.

    PubMed

    Zhong, Liqiang; Song, Chao; Wang, Minghua; Chen, Youming; Qin, Qin; Pan, Jianlin; Chen, Xiaohui

    2013-10-01

    Genetic diversity and population structure of yellow catfish Pelteobagrus fulvidraco were examined by using mitochondrial DNA control region sequences in 143 specimens sampled from five lakes in the middle and lower reaches of the Yangtze River, China; 151 polymorphic sites defined 72 distinct haplotypes. Haplotype diversity indices (0.903-0.953) and nucleotide diversity indices (0.00378-0.00970) demonstrated low genetic diversity of the yellow catfish populations in the five lakes. The analysis of molecular variance and the fixation index (F(st) = 0.0896) revealed insignificant genetic difference between samples from different lakes. In addition, neutral tests and analysis of mismatch distribution suggested that yellow catfish might have undergone a population expansion. Neighbor-joining tree indicated a correlation between these population genetic differences and geographic distance. This study revealed the extant population genetic diversity and structure of the yellow catfish and was in favor of the related fishery management issues including fishery stock identification, conservation, and artificial breeding. PMID:23463981

  17. Lampreys as Diverse Model Organisms in the Genomics Era

    PubMed Central

    McCauley, David W.; Docker, Margaret F.; Whyard, Steve; Li, Weiming

    2015-01-01

    Lampreys, one of the two surviving groups of ancient vertebrates, have become important models for study in diverse fields of biology. Lampreys (of which there are approximately 40 species) are being studied, for example, (a) to control pest sea lamprey in the North American Great Lakes and to restore declining populations of native species elsewhere; (b) in biomedical research, focusing particularly on the regenerative capability of lampreys; and (c) by developmental biologists studying the evolution of key vertebrate characters. Although a lack of genetic resources has hindered research on the mechanisms regulating many aspects of lamprey life history and development, formerly intractable questions are now amenable to investigation following the recent publication of the sea lamprey genome. Here, we provide an overview of the ways in which genomic tools are currently being deployed to tackle diverse research questions and suggest several areas that may benefit from the availability of the sea lamprey genome. PMID:26951616

  18. Controlling effective aspect ratio and packing of clay with pH for improved gas barrier in nanobrick wall thin films.

    PubMed

    Hagen, David A; Saucier, Lauren; Grunlan, Jaime C

    2014-12-24

    Polymer-clay thin films constructed via layer-by-layer (LbL) assembly, with a nanobrick wall structure (i.e., clay nanoplatelets as bricks surrounded by a polyelectrolyte mortar), are known to exhibit a high oxygen barrier. Further barrier improvement can be achieved by lowering the pH of the clay suspension in the polyethylenimine (PEI) and montmorillonite (MMT) system. In this case, the charge of the deposited PEI layer is increased in the clay suspension environment, which causes more clay to be deposited. At pH 4, MMT platelets deposit with near perfect ordering, observed with transmission electron microscopy, enabling a 5 improvement in the gas barrier for a 10 PEI/MMT bilayer thin film (85 nm) relative to the same film made with pH 10 MMT. This improved gas barrier approaches that achieved with much higher aspect ratio vermiculite clay. In essence, lower pH is generating a higher effective aspect ratio for MMT due to greater induced surface charge in the PEI layers, which causes heavier clay deposition. These flexible, transparent nanocoatings have a wide range of possible applications, from food and electronics packaging to pressurized bladders. PMID:25474229

  19. Diverse Classrooms, Diverse Curriculum, Diverse Complications: Three Teacher Perspectives

    ERIC Educational Resources Information Center

    Ungemah, Lori D.

    2015-01-01

    Racial, ethnic, linguistic, and religious diversity continues to increase in classrooms. Many call for a more diverse curriculum, but curricular diversity brings its own challenges to both teachers and students. These three vignettes are drawn from my ethnographic data at Atlantic High School in Brooklyn, New York, where I worked for ten years as

  20. Diverse Classrooms, Diverse Curriculum, Diverse Complications: Three Teacher Perspectives

    ERIC Educational Resources Information Center

    Ungemah, Lori D.

    2015-01-01

    Racial, ethnic, linguistic, and religious diversity continues to increase in classrooms. Many call for a more diverse curriculum, but curricular diversity brings its own challenges to both teachers and students. These three vignettes are drawn from my ethnographic data at Atlantic High School in Brooklyn, New York, where I worked for ten years as…

  1. Plant diversity predicts beta but not alpha diversity of soil microbes across grasslands worldwide

    USGS Publications Warehouse

    Prober, Suzanne M.; Leff, Jonathan W.; Bates, Scott T.; Borer, Elizabeth T.; Firn, Jennifer; Harpole, W. Stanley; Lind, Eric M.; Seabloom, Eric W.; Adler, Peter B.; Bakker, Jonathan D.; Cleland, Elsa E.; DeCrappeo, Nicole; DeLorenze, Elizabeth; Hagenah, Nicole; Hautier, Yann; Hofmockel, Kirsten S.; Kirkman, Kevin P.; Knops, Johannes M. H.; La Pierre, Kimberly J.; MacDougall, Andrew S.; McCulley, Rebecca L.; Mitchell, Charles E.; Risch, Anita C.; Schuetz, Martin; Stevens, Carly J.; Williams, Ryan J.; Fierer, Noah

    2015-01-01

    Aboveground–belowground interactions exert critical controls on the composition and function of terrestrial ecosystems, yet the fundamental relationships between plant diversity and soil microbial diversity remain elusive. Theory predicts predominantly positive associations but tests within single sites have shown variable relationships, and associations between plant and microbial diversity across broad spatial scales remain largely unexplored. We compared the diversity of plant, bacterial, archaeal and fungal communities in one hundred and forty-five 1 m2 plots across 25 temperate grassland sites from four continents. Across sites, the plant alpha diversity patterns were poorly related to those observed for any soil microbial group. However, plant beta diversity (compositional dissimilarity between sites) was significantly correlated with the beta diversity of bacterial and fungal communities, even after controlling for environmental factors. Thus, across a global range of temperate grasslands, plant diversity can predict patterns in the composition of soil microbial communities, but not patterns in alpha diversity.

  2. Cell wall evolution and diversity

    PubMed Central

    Fangel, Jonatan U.; Ulvskov, Peter; Knox, J. P.; Mikkelsen, Maria D.; Harholt, Jesper; Popper, Zo A.; Willats, William G.T.

    2012-01-01

    Plant cell walls display a considerable degree of diversity in their compositions and molecular architectures. In some cases the functional significance of a particular cell wall type appears to be easy to discern: secondary cells walls are often reinforced with lignin that provides durability; the thin cell walls of pollen tubes have particular compositions that enable their tip growth; lupin seed cell walls are characteristically thickened with galactan used as a storage polysaccharide. However, more frequently the evolutionary mechanisms and selection pressures that underpin cell wall diversity and evolution are unclear. For diverse green plants (chlorophytes and streptophytes) the rapidly increasing availability of transcriptome and genome data sets, the development of methods for cell wall analyses which require less material for analysis, and expansion of molecular probe sets, are providing new insights into the diversity and occurrence of cell wall polysaccharides and associated biosynthetic genes. Such research is important for refining our understanding of some of the fundamental processes that enabled plants to colonize land and to subsequently radiate so comprehensively. The study of cell wall structural diversity is also an important aspect of the industrial utilization of global polysaccharide bio-resources. PMID:22783271

  3. Preliminary Aspects of Language Course Evaluation

    ERIC Educational Resources Information Center

    Zohrabi, Mohammad

    2012-01-01

    Program and/or course evaluation is a process in which different types of data are collected systematically in order to study the virtues and weaknesses of a language instruction program. Program evaluation is, in fact, one of the essential aspects of any curriculum. It is a kind of quality control in which various aspects of an instructional

  4. Preliminary Aspects of Language Course Evaluation

    ERIC Educational Resources Information Center

    Zohrabi, Mohammad

    2012-01-01

    Program and /or course evaluation is a process in which different types of data are collected systematically in order to study the virtues and weaknesses of a language instruction program. Program evaluation is, in fact, one of the essential aspects of any curriculum. It is a kind of quality control in which various aspects of an instructional

  5. Devotion, Diversity, and Reasoning: Religion and Medical Ethics.

    PubMed

    Dahnke, Michael D

    2015-12-01

    Most modern ethicists and ethics textbooks assert that religion holds little or no place in ethics, including fields of professional ethics like medical ethics. This assertion, of course, implicitly refers to ethical reasoning, but there is much more to the ethical life and the practice of ethics-especially professional ethics-than reasoning. It is no surprise that teachers of practical ethics, myself included, often focus on reasoning to the exclusion of other aspects of the ethical life. Especially for those with a philosophical background, reasoning is the most patent and pedagogically controllable aspect of the ethical life-and the most easily testable. And whereas there may be powerful reasons for the limitation of religion in this aspect of ethics, there are other aspects of the ethical life in which recognition of religious belief may arguably be more relevant and possibly even necessary. I divide the ethical life into three areas-personal morality, interpersonal morality, and rational morality-each of which I explore in terms of its relationship to religion, normatively characterized by the qualities of devotion, diversity, and reasoning, respectively. PMID:26323531

  6. The Quest for Diversity in Christian Higher Education: Building Institutional Governance Capacity

    ERIC Educational Resources Information Center

    Nussbaum, Kathleen B.; Chang, Heewon

    2013-01-01

    Social justice pertaining to diversity issues in higher education grips the nation, yet Christian higher education (CHE) has moved slowly to address the diversity in our institutions and society. Christian higher education faces the same challenges with growing diversity as secular higher education. Diversity impacts every aspect of institutional…

  7. The Quest for Diversity in Christian Higher Education: Building Institutional Governance Capacity

    ERIC Educational Resources Information Center

    Nussbaum, Kathleen B.; Chang, Heewon

    2013-01-01

    Social justice pertaining to diversity issues in higher education grips the nation, yet Christian higher education (CHE) has moved slowly to address the diversity in our institutions and society. Christian higher education faces the same challenges with growing diversity as secular higher education. Diversity impacts every aspect of institutional

  8. Wind-tunnel investigation of longitudinal and lateral-directional stability and control characteristics of a 0.237-scale model of a remotely piloted research vehicle with a thick, high-aspect-ratio supercritical wing

    NASA Technical Reports Server (NTRS)

    Byrdsong, T. A.; Brooks, C. W., Jr.

    1980-01-01

    A 0.237-scale model of a remotely piloted research vehicle equipped with a thick, high-aspect-ratio supercritical wing was tested in the Langley 8-foot transonic tunnel to provide experimental data for a prediction of the static stability and control characteristics of the research vehicle as well as to provide an estimate of vehicle flight characteristics for a computer simulation program used in the planning and execution of specific flight-research mission. Data were obtained at a Reynolds number of 16.5 x 10 to the 6th power per meter for Mach numbers up to 0.92. The results indicate regions of longitudinal instability; however, an adequate margin of longitudinal stability exists at a selected cruise condition. Satisfactory effectiveness of pitch, roll, and yaw control was also demonstrated.

  9. Qualitative and quantitative aspects of information processing in first psychosis: latent class analyses in patients, at-risk subjects, and controls.

    PubMed

    van Tricht, Mirjam J; Bour, Lo J; Koelman, Johannes H T M; Derks, Eske M; Braff, David L; de Wilde, Odette M; Boere, Thijs; Linszen, Don H; de Haan, Lieuwe; Nieman, Dorien H

    2015-04-01

    We aimed to determine profiles of information processing deficits in the pathway to first psychosis. Sixty-one subjects at ultrahigh risk (UHR) for psychosis were assessed, of whom 18 converted to a first episode of psychosis (FEP) within the follow-up period. Additionally, 47 FEP and 30 control subjects were included. Using 10 neurophysiological parameters associated with information processing, latent class analyses yielded three classes at baseline. Class membership was related to group status. Within the UHR sample, two classes were found. Transition to psychosis was nominally associated with class membership. Neurophysiological profiles were unstable over time, but associations between specific neurophysiological components at baseline and follow-up were found. We conclude that certain constellations of neurophysiological variables aid in the differentiation between controls and patients in the prodrome and after first psychosis. PMID:25376718

  10. Stability and control characteristics of an airplane model having a 45.1 degree swept-back wing with aspect ratio 2.50 and taper ratio 0.42 and a 42.8 degree swept-back horizontal tail with aspect ratio 3.87 and taper ratio 0.49

    NASA Technical Reports Server (NTRS)

    Schuldenfrei, Marvin; Comisarow, Paul; Goodson, Kenneth W

    1947-01-01

    Tests were made of an airplane model having a 45.1 degree swept-back wing with aspect ratio 2.50 and taper ratio 0.42 and a 42.8 degree swept-back horizontal tail with aspect ratio 3.87 and taper ratio 0.49 to determine its low-speed stability and control characteristics. The test Reynolds number was 2.87 x 10(6) based on a mean aerodynamic chord of 2.47 feet except for some of the aileron tests which were made at a Reynolds number of 2.05 x 10(6). With the horizontal tail located near the fuselage juncture on the vertical tail, model results indicated static longitudinal instability above a lift coefficient that was 0.15 below the lift coefficient at which stall occurred. Static longitudinal stability, however, was manifested throughout the life range with the horizontal tail located near the top of the vertical tail. The use of 10 degrees negative dihedral on the wing had little effect on the static longitudinal stability characteristics. Preliminary tests of the complete model revealed an undesirable flat spot in the yawing-moment curves at low angles of attack, the directional stability being neutral for yaw angles of plus-or-minus 2 degrees. This undesirable characteristic was improved by replacing the thick original vertical tail with a thin vertical tail and by flattening the top of the dorsal fairing.

  11. Local ensemble transform Kalman filter, a fast non-stationary control law for adaptive optics on ELTs: theoretical aspects and first simulation results

    NASA Astrophysics Data System (ADS)

    Gray, Morgan; Petit, Cyril; Rodionov, Sergey; Bocquet, Marc; Bertino, Laurent; Ferrari, Marc; Fusco, Thierry

    2014-08-01

    We propose a new algorithm for an adaptive optics system control law, based on the Linear Quadratic Gaussian approach and a Kalman Filter adaptation with localizations. It allows to handle non-stationary behaviors, to obtain performance close to the optimality defined with the residual phase variance minimization criterion, and to reduce the computational burden with an intrinsically parallel implementation on the Extremely Large Telescopes (ELTs).

  12. Local ensemble transform Kalman filter, a fast non-stationary control law for adaptive optics on ELTs: theoretical aspects and first simulation results.

    PubMed

    Gray, Morgan; Petit, Cyril; Rodionov, Sergey; Bocquet, Marc; Bertino, Laurent; Ferrari, Marc; Fusco, Thierry

    2014-08-25

    We propose a new algorithm for an adaptive optics system control law, based on the Linear Quadratic Gaussian approach and a Kalman Filter adaptation with localizations. It allows to handle non-stationary behaviors, to obtain performance close to the optimality defined with the residual phase variance minimization criterion, and to reduce the computational burden with an intrinsically parallel implementation on the Extremely Large Telescopes (ELTs). PMID:25321291

  13. Personalized medicine and human genetic diversity.

    PubMed

    Lu, Yi-Fan; Goldstein, David B; Angrist, Misha; Cavalleri, Gianpiero

    2014-09-01

    Human genetic diversity has long been studied both to understand how genetic variation influences risk of disease and infer aspects of human evolutionary history. In this article, we review historical and contemporary views of human genetic diversity, the rare and common mutations implicated in human disease susceptibility, and the relevance of genetic diversity to personalized medicine. First, we describe the development of thought about diversity through the 20th century and through more modern studies including genome-wide association studies (GWAS) and next-generation sequencing. We introduce several examples, such as sickle cell anemia and Tay-Sachs disease that are caused by rare mutations and are more frequent in certain geographical populations, and common treatment responses that are caused by common variants, such as hepatitis C infection. We conclude with comments about the continued relevance of human genetic diversity in medical genetics and personalized medicine more generally. PMID:25059740

  14. Binding of dietary polyphenols to cellulose: structural and nutritional aspects.

    PubMed

    Phan, Anh Dao T; Netzel, Gabriele; Wang, Dongjie; Flanagan, Bernadine M; D'Arcy, Bruce R; Gidley, Michael J

    2015-03-15

    The interactions between polyphenols and plant fibres play an important role in controlling the release of phenolic compounds from food matrices for absorption in the gastrointestinal tract. This study probed the molecular interactions of diverse polyphenols with cellulose fibres by using a pure cellulose-producing bacterial model. Alkali treatment of bacterial cellulose was an effective method for obtaining a high purity cellulose model for study of polyphenol binding. Representatives of different polyphenol classes all bound to cellulose spontaneously, rapidly, and to comparable extents (up to 60% w/w of cellulose). Langmuir binding isotherms were applied to determine quantitative aspects of the adsorption at equilibrium. The study indicated that binding was similar on a molar basis for ferulic acid, gallic acid, catechin and cyanidin-3-glucoside (but lower for chlorogenic acid), with the native charge of polyphenols a secondary factor in the interactions between polyphenols and cellulose. PMID:25308685

  15. Psychosocial aspects in phenylketonuria.

    PubMed

    Weglage, J; Fünders, B; Ullrich, K; Rupp, A; Schmidt, E

    1996-07-01

    Psychosocial aspects in phenylketonuric (PKU) patients are reported. In two separate studies patients with PKU differing in age (children versus adolescents), were assessed. The main message of the first prospective study on 58 10-year-old patients is that normally intelligent PKU patients who were treated early and strictly did not show a higher risk for severe emotional and behavioural maladjustment compared with healthy controls at the age of 10 years. The data were obtained in the course of the German PKU Collaborative Study by the "Personality Questionnaire for Children (PFK 9-14)". All patients received nutritional, medical, and psychological counselling every 6 months. In the second retrospective study, 34 early treated, normally intelligent adolescents with PKU (age: mean = 14.6, SD = 2.0, range = 11-18 years) and their mothers were assessed with several psychometric personality inventories and self-developed questionnaires concerning their psychosocial situation and their disease- and diet-specific knowledge. Using the Mannheimer Biographic Inventory (MBI), the Personality Questionnaire for Children (PFK 9-14), and the Freiburger Personality Inventory (FPI) the adolescent patients described their social life and their emotional development as being distinctly restricted. Their knowledge concerning disease and diet was alarmingly poor and the majority had great difficulties in satisfactory dietetic management without parental help. In addition to the burdensome diet, developmental crises like puberty may cause more frequently emotional and behavioural problems in PKU patients. PMID:8828622

  16. The nuclear hormone receptor family member NR5A2 controls aspects of multipotent progenitor cell formation and acinar differentiation during pancreatic organogenesis

    PubMed Central

    Hale, Michael A.; Swift, Galvin H.; Hoang, Chinh Q.; Deering, Tye G.; Masui, Toshi; Lee, Youn-Kyoung; Xue, Jumin; MacDonald, Raymond J.

    2014-01-01

    The orphan nuclear receptor NR5A2 is necessary for the stem-like properties of the epiblast of the pre-gastrulation embryo and for cellular and physiological homeostasis of endoderm-derived organs postnatally. Using conditional gene inactivation, we show that Nr5a2 also plays crucial regulatory roles during organogenesis. During the formation of the pancreas, Nr5a2 is necessary for the expansion of the nascent pancreatic epithelium, for the subsequent formation of the multipotent progenitor cell (MPC) population that gives rise to pre-acinar cells and bipotent cells with ductal and islet endocrine potential, and for the formation and differentiation of acinar cells. At birth, the NR5A2-deficient pancreas has defects in all three epithelial tissues: a partial loss of endocrine cells, a disrupted ductal tree and a >90% deficit of acini. The acinar defects are due to a combination of fewer MPCs, deficient allocation of those MPCs to pre-acinar fate, disruption of acinar morphogenesis and incomplete acinar cell differentiation. NR5A2 controls these developmental processes directly as well as through regulatory interactions with other pancreatic transcriptional regulators, including PTF1A, MYC, GATA4, FOXA2, RBPJL and MIST1 (BHLHA15). In particular, Nr5a2 and Ptf1a establish mutually reinforcing regulatory interactions and collaborate to control developmentally regulated pancreatic genes by binding to shared transcriptional regulatory regions. At the final stage of acinar cell development, the absence of NR5A2 affects the expression of Ptf1a and its acinar specific partner Rbpjl, so that the few acinar cells that form do not complete differentiation. Nr5a2 controls several temporally distinct stages of pancreatic development that involve regulatory mechanisms relevant to pancreatic oncogenesis and the maintenance of the exocrine phenotype. PMID:25063451

  17. Phenomenological aspects of quasi-stationary controlled and uncontrolled three-dimensional flow separations. [in relation to aircraft design considerations and swept wings

    NASA Technical Reports Server (NTRS)

    Peake, D. J.

    1978-01-01

    Quasi-steady three dimensional separated flows about bodies of large fineness ratio operating at large angles of incidence or yaw are discussed. The general character of the three dimensional attached boundary layer, the concept of limiting streamlines, and the physics of three dimensional separation and reattachment are among the factors considered. Specific examples are given. The advantages of swept, sharp edges that generate controlled (or fixed) three dimensional flow separations on a vehicle, due to the qualitatively unchanging flow field developed throughout the range of flight conditions, are emphasized.

  18. Transcription Factors GATA4 and HNF4A Control Distinct Aspects of Intestinal Homeostasis in Conjunction with Transcription Factor CDX2*

    PubMed Central

    San Roman, Adrianna K.; Aronson, Boaz E.; Krasinski, Stephen D.; Shivdasani, Ramesh A.; Verzi, Michael P.

    2015-01-01

    Distinct groups of transcription factors (TFs) assemble at tissue-specific cis-regulatory sites, implying that different TF combinations may control different genes and cellular functions. Within such combinations, TFs that specify or maintain a lineage and are therefore considered master regulators may play a key role. Gene enhancers often attract these tissue-restricted TFs, as well as TFs that are expressed more broadly. However, the contributions of the individual TFs to combinatorial regulatory activity have not been examined critically in many cases in vivo. We address this question using a genetic approach in mice to inactivate the intestine-specifying and intestine-restricted factor CDX2 alone or in combination with its more broadly expressed partner factors, GATA4 and HNF4A. Compared with single mutants, each combination produced significantly greater defects and rapid lethality through distinct anomalies. Intestines lacking Gata4 and Cdx2 were deficient in crypt cell replication, whereas combined loss of Hnf4a and Cdx2 specifically impaired viability and maturation of villus enterocytes. Integrated analysis of TF binding and of transcripts affected in Hnf4a;Cdx2 compound-mutant intestines indicated that this TF pair controls genes required to construct the apical brush border and absorb nutrients, including dietary lipids. This study thus defines combinatorial TF activities, their specific requirements during tissue homeostasis, and modules of transcriptional targets in intestinal epithelial cells in vivo. PMID:25488664

  19. Control of a type 1 poliomyelitis epidemic in British Guiana, 1962-63, with trivalent oral poliovirus vaccine. 2. Virological aspects.

    PubMed

    Feldman, R A; Mootoo, C L; Spence, L; Gelfand, H M

    1965-01-01

    Epidemics of paralytic poliomyelitis have been reported with increasing frequency in the Caribbean area over the last decade. During the first weeks of a type 1 poliomyelitis epidemic in British Guiana in the winter of 1962-63, it was possible to study "wild" poliovirus infections in pre-school children, and to obtain information concerning the effectiveness of a country-wide control programme using trivalent oral poliovirus vaccine.Serological studies indicated that many Guianese children had had previous asymptomatic poliovirus infections by school age. However, there were more children with antibodies to types 2 and 3 than with antibodies to type 1. Following the first of two feedings of trivalent vaccine, there were significant increases in the percentage of children with poliovirus antibodies.Though begun only three weeks after the hospitalization of several paralysed children, a rectal-swab survey indicated that in some areas over one-third of the pre-school children were excreting "wild" poliovirus. In one area of the country, where only 2% of the children were excreting poliovirus type 1, vaccine feeding seemed most effective in containing the epidemic. These results support the suggestion that to be successful an epidemic control programme in a developing tropical country should be rapidly organized and completed. PMID:4284022

  20. Current status of management, control, complications and psychosocial aspects of patients with diabetes in India: Results from the DiabCare India 2011 Study

    PubMed Central

    Mohan, Viswanathan; Shah, Siddharth N.; Joshi, Shashank R.; Seshiah, V.; Sahay, Binode Kumar; Banerjee, Samar; Wangnoo, Subhash Kumar; Kumar, Ajay; Kalra, Sanjay; Unnikrishnan, A. G.; Sharma, Surendra Kumar; Rao, P. V.; Akhtar, Shahid; Shetty, Raman V.; Das, Ashok Kumar

    2014-01-01

    Objectives: DiabCare India 2011 was a cross-sectional study in patients with diabetes mellitus, undertaken to investigate the relationship between diabetes control, management and complications in a subset of urban Indian diabetes patients treated at referral diabetes care centres in India. Materials and Methods: This was a cross-sectional, multicentre (330 centres) survey in 6168 diabetes patients treated at general hospitals, diabetes clinics and referral clinics across India. Patient data, including medical and clinical examination reports during the past year were collected during their routine visit. The patients’ and physicians’ perceptions about diabetes management were recorded using a questionnaire. Results: A total of 6168 subjects with diabetes (95.8% type 2), mean age 51.9 ± 12.4 years and mean duration of diabetes, 6.9 ± 6.4 years were included. Mean HbA1c was 8.9 ± 2.1% and the mean fasting (FPG), post prandial (PPG) and random (RBG) plasma glucose levels were 148 ± 50 mg/dl 205 ± 66 mg/dl and 193 ± 68mg/dl respectively. Neuropathy was the most common complication (41.4%); other complications were: Foot (32.7%), eye (19.7%), cardiovascular (6.8%) and nephropathy (6.2%). The number of diabetic complications increased with mean duration of diabetes. Most (93.2%) of the patients were on oral anti-diabetic drugs (OADs) and 35.2% were on insulin (±OADs). More than 15% physicians felt that the greatest barrier to insulin therapy from patient's perspective were pain and fear of using injectable modality; 5.2% felt that the greatest barrier to insulin therapy from physician's perspective was the treatment cost; 4.8% felt that the major barriers to achieve optimum diabetic care in practice was loss to follow-up followed by lack of counselling (3.9%) and treatment compliance (3.6%). Conclusion: DiabCare India 2011 has shown that type 2 diabetes sets in early in Indians and glycaemic control is often sub-optimal in these patients. These results indicate a need for more structured intervention at an early stage of the disease and need for increased awareness on benefits of good glycaemic control. It cannot be overemphasized that the status of diabetes care in India needs to be further improved. (ClinTrials.gov identifier: NCT01351922) PMID:24944934

  1. Diversity and Leadership in a Changing World

    ERIC Educational Resources Information Center

    Eagly, Alice H.; Chin, Jean Lau

    2010-01-01

    Scholars of leadership have infrequently addressed the diversity of leaders and followers in terms of culture, gender, race and ethnicity, or sexual orientation. This omission has weakened the ability of research and theory to address some of the most provocative aspects of contemporary leadership, including (a) the limited access of individuals

  2. Angiosperm ovules: diversity, development, evolution

    PubMed Central

    Endress, Peter K.

    2011-01-01

    Background Ovules as developmental precursors of seeds are organs of central importance in angiosperm flowers and can be traced back in evolution to the earliest seed plants. Angiosperm ovules are diverse in their position in the ovary, nucellus thickness, number and thickness of integuments, degree and direction of curvature, and histological differentiations. There is a large body of literature on this diversity, and various views on its evolution have been proposed over the course of time. Most recently evo–devo studies have been concentrated on molecular developmental genetics in ovules of model plants. Scope The present review provides a synthetic treatment of several aspects of the sporophytic part of ovule diversity, development and evolution, based on extensive research on the vast original literature and on experience from my own comparative studies in a broad range of angiosperm clades. Conclusions In angiosperms the presence of an outer integument appears to be instrumental for ovule curvature, as indicated from studies on ovule diversity through the major clades of angiosperms, molecular developmental genetics in model species, abnormal ovules in a broad range of angiosperms, and comparison with gymnosperms with curved ovules. Lobation of integuments is not an atavism indicating evolution from telomes, but simply a morphogenetic constraint from the necessity of closure of the micropyle. Ovule shape is partly dependent on locule architecture, which is especially indicated by the occurrence of orthotropous ovules. Some ovule features are even more conservative than earlier assumed and thus of special interest in angiosperm macrosystematics. PMID:21606056

  3. 10 Diversity Champions II

    ERIC Educational Resources Information Center

    Nealy, Michelle J.; Pluviose, David; Roach, Ronald

    2008-01-01

    Introducing the "Champions of Diversity" in the Academic Kickoff issue proved a timely reminder of the mission of Diverse during the lead up to the 25th anniversary of Cox, Matthews and Associates, the founder of the former Black Issues in Higher Education and publisher of Diverse. In this edition, the editors at Diverse unveil its second slate of

  4. Cognitive diversity and moral enhancement.

    PubMed

    Gyngell, Chris; Easteal, Simon

    2015-01-01

    One debate in contemporary bioethics centers on whether the development of cognitive enhancement technologies (CETs) will hasten the need for moral enhancement. In this article we provide a new argument in favor of pursuing these enhancement technologies together. The widespread availability of CETs will likely increase population-level cognitive diversity. Different people will choose to enhance different aspects of their cognition, and some won't enhance themselves at all. Although this has the potential to be beneficial for society, it could also result in harms as people become more different from one another. Aspects of our moral psychology make it difficult for people to cooperate and coordinate actions with those who are very different from themselves. These moral failings could be targeted by moral enhancement technologies, which may improve cooperation among individuals. Moral enhancement technologies will therefore help society maximize the benefits, and reduce the costs, associated with widespread access to cognitive enhancements. PMID:25473859

  5. [Ecological and epidemiologic aspects of the attacks by vampire bats and paralytic rabies in Argentina and analysis of the proposals carried out for their control].

    PubMed

    Delpietro, H A; Russo, R G

    1996-09-01

    The authors describe the ecology of attacks by vampire bats and the epidemiology of rabies (paralytic rabies) transmitted by these bats in Argentina, based on data obtained from an epidemiological vigilance programme conducted between 1984 and 1993. It was found that rabies spread rapidly among vampire bats, causing high mortality (over 50%); subsequently, the population recovered slowly due to the low reproductive rate. This explains the features of paralytic rabies, such as high mortality among affected populations, brief duration and subsequent recurrence. Paralytic rabies occurs throughout the year without evidence of seasonal occurrence and with no relationship to rainfall. This is because vampire bats remain active within their habitat, neither hibernating nor migrating. The problem created by vampire bats depends on the ecosystem of their habitat. In the livestock ecosystem, the bats are synanthropic and their population is abundant. They feed almost exclusively on livestock and attacks on human beings are sporadic. In this ecosystem, paralytic rabies is a serious economic problem because of its frequency and readiness to spread (41 separate outbreaks were recorded in addition to an epidemic). On the contrary, in the scarcely populated livestock ecosystem, the vampire but population is much smaller; they feed on various species of animals, and attacks on human beings are more common, but paralytic rabies occurs only sporadically (one isolated outbreak). For overall control of paralytic rabies, the authors recommend reduction of the vampire bat population to a safe level, in order to break the chain of rabies transmission and diminish attacks by bats. PMID:9376648

  6. Control of a type 1 poliomyelitis epidemic in British Guiana, 1962-63, with trivalent oral poliovirus vaccine. 1. Epidemiological aspects.

    PubMed

    Witte, J J; Page, M I; Gelfand, H M

    1965-01-01

    An epidemic of poliomyelitis took place in British Guiana during the winter of 1962-63. A total of 485 paralytic cases occurred over a 10-week period, 90% in children under 5 years of age.The attack rate for the total population of more than half-a-million persons was 86.5 per 100 000. Type 1 poliovirus was isolated from stool specimens from 90% of the paralytic cases studied. Early in the epidemic, before virus was isolated, plans were developed for an extensive field study to characterize the epidemic and evaluate the effectiveness of trivalent vaccine as a practical control measure.Vaccine was administered to 85% of the children aged 5 or less over a 4-week period. A definite beneficial effect was noted; however, the epidemic might have been more impressively terminated had the programme been more rapidly administered. The importance of early recognition of an outbreak of poliomyelitis and of the rapid planning and execution of a vaccination programme is stressed. PMID:5294260

  7. Long-term nutrient addition differentially alters community composition and diversity of genes that control nitrous oxide flux from salt marsh sediments

    NASA Astrophysics Data System (ADS)

    Kearns, Patrick J.; Angell, John H.; Feinman, Sarah G.; Bowen, Jennifer L.

    2015-03-01

    Enrichment of natural waters, soils, and sediments by inorganic nutrients, including nitrogen, is occurring at an increasing rate and has fundamentally altered global biogeochemical cycles. Salt marshes are critical for the removal of land-derived nitrogen before it enters coastal waters. This is accomplished via multiple microbially mediated pathways, including denitrification. Many of these pathways, however, are also a source of the greenhouse gas nitrous oxide (N2O). We used clone libraries and quantative PCR (qPCR) to examine the effect of fertilization on the diversity and abundance of two functional genes associated with denitrification and N2O production (norB and nosZ) in experimental plots at the Great Sippewissett Salt Marsh (Falmouth, MA, USA) that have been enriched with nutrients for over 40 years. Our data showed distinct nosZ and norB community structures at different nitrogen loads, especially at the highest level of fertilization. Furthermore, calculations of the Shannon Diversity Index and Chao1 Richness Estimator indicated that nosZ gene diversity and richness increased with increased nitrogen supply, however no such relationship existed with regard to richness and diversity of the norB gene. Results from qPCR demonstrated that nosZ gene abundance was an order of magnitude lower in the extra-highly fertilized plots compared to the other plots, but the abundance of norB was not affected by fertilization. The majority of sequences obtained from the marsh plots had no close cultured relatives and they were divergent from previously sequenced norB and nosZ fragments. Despite their divergence from any cultured representatives, most of the norB and nosZ sequences appeared to be from members of the Alpha- and Betaproteobacteria, suggesting that these classes are particularly important in salt marsh nitrogen cycling. Our results suggest that both norB and nosZ containing microbes are affected by fertilization and that the Great Sippewissett Marsh may harbor distinct clades of novel denitrifying microorganisms that are responsible for both the production and removal of N2O.

  8. Aspects of Three Dimensional Transport for ELM Control Experiments in ITER-Similar Shape Plasmas at Low Collisionality in DIII-D

    SciTech Connect

    Schmitz, O.; Evans, T. E.; Fenstermacher, M. E.; Frerichs, H.; Jakubowski, M. W.; Schaffer, M. J.; Wingen, A.; West, W. P.; Brooks, N. H.; Burrell, K. H.; DeGrassie, J. S.; Feng, Y.; Finken, K. H.; Gohil, P.; Groth, M.; Joseph, I.; Lasnier, C. J.; Lehnen, M.; Leonard, A. W.; Mordijck, S.; Moyer, R.A.; Nicolai, A.; Osborne, T. H.; Reiter, D.; Samm, U.; Spatschek, K. H.; Stoschus, H.; Unterberg, Ezekial A; Watkins, J. G.; Wolf, R. C.

    2008-01-01

    A study of three-dimensional (3D) perturbed magnetic field structures and transport for edge localized mode control experiments with resonant magnetic perturbations at DIII-D is presented. We focus on ITER-Similar Shape plasmas at ITER relevant electron pedestal collisionalities. nu(e)* similar to 0.2. This study is performed in comparison with results from TEXTOR-Dynamic Ergodic Divertor circular limiter plasmas. For both experiments the magnetic field structure is analyzed in the vacuum paradigm-superimposing the external RMP field on the unperturbed equilibrium. For TEXTOR L-mode plasmas this description holds for normalized poloidal flux Psi(N) > 0.7 without tearing modes driven by the RMP field. For DIII-D H-mode plasmas the validity of this approach still needs to be established. In this paper a method is discussed to diagnose the degree of edge stochastization based on a comparison between modeled magnetic footprints on the divertor targets and experimental data. Clear evidence is presented for the existence of a generic separatrix perturbation causing striation of target particle fluxes. However, heat fluxes into these striations are small. This observation can be explained by accounting for the different heat and particle source locations and the 3D trajectories of the open, perturbed field lines toward the divertor target. Analysis of the transport characteristics filling the perturbed separatrix lobes based on initial EMC3/EIRENE modeling suggests the existence of open field lines connecting the stochastic edge to the target pattern. However, the width and inward most extent of the actual stochastic layer cannot yet be quantified.

  9. Design Aspects of a Case-Control Clinical Investigation of the Effect of HIV on Oral and Gastrointestinal Soluble Innate Factors and Microbes

    PubMed Central

    Phelan, Joan A.; Abrams, William R.; Norman, Robert G.; Li, Yihong; Laverty, Maura; Corby, Patricia M.; Nembhard, Jason; Neri, Dinah; Barber, Cheryl A.; Aberg, Judith A.; Fisch, Gene S.; Poles, Michael A.; Malamud, Daniel

    2014-01-01

    Introduction The impaired host defense system in HIV infection impacts the oral and gastrointestinal microbiota and associated opportunistic infections. Antiretroviral treatment is predicted to partially restore host defenses and decrease the oral manifestation of HIV/AIDS. Well-designed longitudinal studies are needed to better understand the interactions of soluble host defense proteins with bacteria and virus in HIV/AIDS. “Crosstalk” was designed as a longitudinal study of host responses along the gastrointestinal (GI) tract and interactions between defense molecules and bacteria in HIV infection and subsequent therapy. Purpose The clinical core formed the infrastructure for the study of the interactions between the proteome, microbiome and innate immune system. The core recruited and retained study subjects, scheduled visits, obtained demographic and medical data, assessed oral health status, collected samples, and guided analysis of the hypotheses. This manuscript presents a well-designed clinical core that may serve as a model for studies that combine clinical and laboratory data. Methods Crosstalk was a case-control longitudinal clinical study an initial planned enrollment of 170 subjects. HIV+ antiretroviral naïve subjects were followed for 9 visits over 96 weeks and HIV uninfected subjects for 3 visits over 24 weeks. Clinical prevalence of oral mucosal lesions, dental caries and periodontal disease were assessed. Results During the study, 116 subjects (47 HIV+, 69 HIV-) were enrolled. Cohorts of HIV+ and HIV- were demographically similar except for a larger proportion of women in the HIV- group. The most prevalent oral mucosal lesions were oral candidiasis and hairy leukoplakia in the HIV+ group. Discussion The clinical core was essential to enable the links between clinical and laboratory data. The study aims to determine specific differences between oral and GI tissues that account for unique patterns of opportunistic infections and to delineate the differences in their susceptibility to infection by HIV and their responses post-HAART. PMID:25409430

  10. Universal-Diverse Orientation: Linking Social Attitudes with Wellness

    ERIC Educational Resources Information Center

    Miville, Marie L.; Romans, John S. C.; Johnson, Daniel; Lone, Robert

    2004-01-01

    The current study focused on examining the relationships of positive social attitudes with aspects of well-functioning. "Universal-diverse orientation" (UDO), a social attitude characterized by awareness and acceptance of both the similarities and differences among people, was measured with the Miville-Guzman Universality-Diversity Scale, Short

  11. Universal-Diverse Orientation: Linking Social Attitudes with Wellness

    ERIC Educational Resources Information Center

    Miville, Marie L.; Romans, John S. C.; Johnson, Daniel; Lone, Robert

    2004-01-01

    The current study focused on examining the relationships of positive social attitudes with aspects of well-functioning. "Universal-diverse orientation" (UDO), a social attitude characterized by awareness and acceptance of both the similarities and differences among people, was measured with the Miville-Guzman Universality-Diversity Scale, Short…

  12. Teacher Education's Responsibility to Address Diversity Issues: Enhancing Institutional Capacity.

    ERIC Educational Resources Information Center

    Melnick, Susan L.; Zeichner, Kenneth M.

    1998-01-01

    Preservice teachers must be prepared to address substantial student diversity and to educate all students to higher levels of understanding and competence. Many teacher educators are not competent to prepare new teachers in this area. Several approaches to handling institutional aspects of teacher education for diversity are discussed, noting

  13. ECOPHYSIOLOGICAL ASPECTS OF ALLELOPATHY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Allelochemicals play an important role in explaining plant growth inhibition in interspecies interactions and in structuring the plant community. Five aspects of allelochemicals are discussed from an ecophysiological perspective: (i) modes of release and avoidance of autotoxicity; (ii) biosynthesis...

  14. Diversity Statements: How Faculty Applicants Address Diversity

    ERIC Educational Resources Information Center

    Schmaling, Karen B.; Trevino, Amira Y.; Lind, Justin R.; Blume, Arthur W.; Baker, Dana L.

    2015-01-01

    The purpose of the present study was to examine application materials for assistant professor positions in 3 academic disciplines. Applicants were asked to write a diversity statement describing how they would advance diversity through their research, teaching, and service. The sample included application materials submitted by 191 candidates for…

  15. Capturing the Diversity in Lexical Diversity

    ERIC Educational Resources Information Center

    Jarvis, Scott

    2013-01-01

    The range, variety, or diversity of words found in learners' language use is believed to reflect the complexity of their vocabulary knowledge as well as the level of their language proficiency. Many indices of lexical diversity have been proposed, most of which involve statistical relationships between types and tokens, and which ultimately

  16. Does Staff Diversity Imply Openness to Diversity?

    ERIC Educational Resources Information Center

    Lauring, Jakob; Selmer, Jan

    2013-01-01

    Purpose: Post-secondary educational organizations are currently some of the most diverse settings to be found. However, few educational studies have dealt with staff diversity and hardly any has looked outside the USA. The purpose of this paper is to present a study of members of international university departments in Denmark. The authors set out

  17. Capturing the Diversity in Lexical Diversity

    ERIC Educational Resources Information Center

    Jarvis, Scott

    2013-01-01

    The range, variety, or diversity of words found in learners' language use is believed to reflect the complexity of their vocabulary knowledge as well as the level of their language proficiency. Many indices of lexical diversity have been proposed, most of which involve statistical relationships between types and tokens, and which ultimately…

  18. Diversity Statements: How Faculty Applicants Address Diversity

    ERIC Educational Resources Information Center

    Schmaling, Karen B.; Trevino, Amira Y.; Lind, Justin R.; Blume, Arthur W.; Baker, Dana L.

    2015-01-01

    The purpose of the present study was to examine application materials for assistant professor positions in 3 academic disciplines. Applicants were asked to write a diversity statement describing how they would advance diversity through their research, teaching, and service. The sample included application materials submitted by 191 candidates for

  19. High Aspect Ratio Wrinkles

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Cheng; Crosby, Alfred

    2015-03-01

    Buckling-induced surface undulations are widely found in living creatures, for instance, gut villi and the surface of flower petal cells. These undulations provide unique functionalities with their extremely high aspect ratios. For the synthetic systems, sinusoidal wrinkles that are induced by buckling a thin film attached on a soft substrate have been proposed to many applications. However, the impact of the synthetic wrinkles have been restricted by limited aspect ratios, ranging from 0 to 0.35. Within this range, wrinkle aspect ratio is known to increase with increasing compressive strain until a critical strain is reached, at which point wrinkles transition to localizations, such as folds or period doublings. Inspired by the living creatures, we propose that wrinkles can be stabilized in high aspect ratio by manipulating the strain energy in the substrate. We experimentally demonstrate this idea by forming a secondary crosslinking network in the wrinkled surface and successfully achieve aspect ratio as large as 0.8. This work not only provides insights for the mechanism of high aspect ratio structures seen in living creatures, but also demonstrates significant promise for future wrinkle-based applications.

  20. How does pedogenesis drive plant diversity?

    USGS Publications Warehouse

    Laliberté, Etienne; Grace, James B.; Huston, Michael A.; Lambers, Hans; Teste, François P.; Turner, Benjamin L.; Wardle, David A.

    2013-01-01

    Some of the most species-rich plant communities occur on ancient, strongly weathered soils, whereas those on recently developed soils tend to be less diverse. Mechanisms underlying this well-known pattern, however, remain unresolved. Here, we present a conceptual model describing alternative mechanisms by which pedogenesis (the process of soil formation) might drive plant diversity. We suggest that long-term soil chronosequences offer great, yet largely untapped, potential as 'natural experiments' to determine edaphic controls over plant diversity. Finally, we discuss how our conceptual model can be evaluated quantitatively using structural equation modeling to advance multivariate theories about the determinants of local plant diversity. This should help us to understand broader-scale diversity patterns, such as the latitudinal gradient of plant diversity.

  1. How does pedogenesis drive plant diversity?

    PubMed

    Lalibert, Etienne; Grace, James B; Huston, Michael A; Lambers, Hans; Teste, Franois P; Turner, Benjamin L; Wardle, David A

    2013-06-01

    Some of the most species-rich plant communities occur on ancient, strongly weathered soils, whereas those on recently developed soils tend to be less diverse. Mechanisms underlying this well-known pattern, however, remain unresolved. Here, we present a conceptual model describing alternative mechanisms by which pedogenesis (the process of soil formation) might drive plant diversity. We suggest that long-term soil chronosequences offer great, yet largely untapped, potential as 'natural experiments' to determine edaphic controls over plant diversity. Finally, we discuss how our conceptual model can be evaluated quantitatively using structural equation modeling to advance multivariate theories about the determinants of local plant diversity. This should help us to understand broader-scale diversity patterns, such as the latitudinal gradient of plant diversity. PMID:23561322

  2. High Aspect Ratio Wrinkles

    NASA Astrophysics Data System (ADS)

    Chen, Yu-Cheng; Crosby, Alfred J.

    2014-03-01

    Wrinkles occur when a compressive strain is imposed on a bilayer system composed of a stiff thin top film and a soft substrate. Wrinkle aspect ratio (wrinkle height divided by wavelength) is perhaps the most critical parameter for many promising wrinkle-based technologies; however, the current accessible range of aspect ratio has been restricted from 0 to 0.35. Within this range, wrinkle aspect ratio is known to increase with increasing compressive strain until a critical strain is reached, at which point wrinkles transition to localizations, such as folds or ridges. Here, we demonstrate the ability to delay this transition and ultimately expand the range of aspect ratios. Building upon recently developed models which link this transition to the asymmetric traction forces between the wrinkle crests and valleys for non-linear strain energy functions, we experimentally quantify the critical strain for both ridge and fold localizations as a function of the substrate material properties, initial stretch ratio, as well as film properties and geometry. Collectively, we demonstrate the ability to achieve wrinkle aspect ratios as large as 0.8, demonstrating significant promise for future wrinkle-based applications.

  3. [Medical aspects of fasting].

    PubMed

    Gavrankapetanovi?, F

    1997-01-01

    Fasting (arabic-savm) was proclaimed through islam, and thus it is an obligation for Holly Prophet Muhammad s.a.v.s.-Peace be to Him-in the second year after Hijra (in 624 after Milad-born of Isa a.s.). There is a month of fasting-Ramadan-each lunar (hijra) year. So, it was 1415th fasting this year. Former Prophets have brought obligative messages on fasting to their people; so there are also certain forms of fasting with other religions i.e. with Catholics, Jews, Orthodox. These kinds of fasting above differ from muslim fasting, but they also appear obligative. All revelations have brought fasting as obligative. From medical point of view, fasting has two basical components: psychical and physical. Psychical sphere correlate closely with its fundamental ideological message. Allah dz.s. says in Quran: "... Fasting is obligative for you, as it was obligative to your precedents, as to avoid sins; during very few days (II, II, 183 & 184)." Will strength, control of passions, effort and self-discipline makes a pure faithfull person, who purify its mind and body through fasting. Thinking about The Creator is more intensive, character is more solid; and spirit and will get stronger. We will mention the hadith saying: "Essaihune humus saimun!" That means: "Travellers at the Earth are fasters (of my ummet)." The commentary of this hadith, in the Collection of 1001 hadiths (Bin bir hadis), number 485, says: "There are no travelling dervishs or monks in islam; thus there is no such a kind of relligousity in islam. In stead, it is changed by fasting and constant attending of mosque. That was proclaimed as obligation, although there were few cases of travelling in the name of relligousity, like travelling dervishs and sheichs." In this paper, the author discusses medical aspects of fasting and its positive characteristics in the respect of healthy life style and prevention of many sicks. The author mentions positive influence of fasting to certain system and organs of human body. According the author, o basic messages of fasting could be a Roman poet's saying:" Mens sana in corpora sanum." PMID:9324567

  4. Leadership and Diversity

    ERIC Educational Resources Information Center

    Coleman, Marianne

    2012-01-01

    As part of the special edition recognizing the 40th anniversary of "Educational Management Administration & Leadership" this article reviews the coverage of leadership and diversity issues in the journal. The majority of articles concerning diversity have focused on gender, with attention turning to the wider concept of diversity since the year

  5. Insights on Diversity.

    ERIC Educational Resources Information Center

    Bloom, Carol, Ed.; And Others

    This state-of-the-art report presents a series of essays on the topic of diversity. Essays include: (1) "Committing to Diversity" (George L. Mehaffy); (2) "Serving the Community by Serving Our Members" (Michael P. Wolfe); (3) "How Diversity Matters" (Asa G. Hilliard, III); (4) "A Prerequisite to Teaching Multiculturally" (Mary Louise Gomez); (5)…

  6. BioDiversity.

    ERIC Educational Resources Information Center

    Wilson, E. O., Ed.; Peter, Frances M., Ed.

    The diversity of life forms is one of the greatest wonders of the planet earth. The biosphere is an intricate tapestry of interwoven life forms. This book offers an overall view of this biological diversity and carries an urgent warning about the rapid alteration and destruction of the environments that have fostered the diversity of life forms…

  7. Multilevel and Diverse Classrooms

    ERIC Educational Resources Information Center

    Baurain, Bradley, Ed.; Ha, Phan Le, Ed.

    2010-01-01

    The benefits and advantages of classroom practices incorporating unity-in-diversity and diversity-in-unity are what "Multilevel and Diverse Classrooms" is all about. Multilevel classrooms--also known as mixed-ability or heterogeneous classrooms--are a fact of life in ESOL programs around the world. These classrooms are often not only multilevel…

  8. Multilevel and Diverse Classrooms

    ERIC Educational Resources Information Center

    Baurain, Bradley, Ed.; Ha, Phan Le, Ed.

    2010-01-01

    The benefits and advantages of classroom practices incorporating unity-in-diversity and diversity-in-unity are what "Multilevel and Diverse Classrooms" is all about. Multilevel classrooms--also known as mixed-ability or heterogeneous classrooms--are a fact of life in ESOL programs around the world. These classrooms are often not only multilevel

  9. BioDiversity.

    ERIC Educational Resources Information Center

    Wilson, E. O., Ed.; Peter, Frances M., Ed.

    The diversity of life forms is one of the greatest wonders of the planet earth. The biosphere is an intricate tapestry of interwoven life forms. This book offers an overall view of this biological diversity and carries an urgent warning about the rapid alteration and destruction of the environments that have fostered the diversity of life forms

  10. Cognitive aspects of color

    NASA Astrophysics Data System (ADS)

    Derefeldt, Gunilla A. M.; Menu, Jean-Pierre; Swartling, Tiina

    1995-04-01

    This report surveys cognitive aspects of color in terms of behavioral, neuropsychological, and neurophysiological data. Color is usually defined as psychophysical color or as perceived color. Behavioral data on categorical color perception, absolute judgement of colors, color coding, visual search, and visual awareness refer to the more cognitive aspects of color. These are of major importance in visual synthesis and spatial organization, as already shown by the Gestalt psychologists. Neuropsychological and neurophysiological findings provide evidence for an interrelation between cognitive color and spatial organization. Color also enhances planning strategies, as has been shown by studies on color and eye movements. Memory colors and the color- language connections in the brain also belong among the cognitive aspects of color.

  11. [Pulmonary Echinococcosis: Surgical Aspects].

    PubMed

    Eichhorn, M E; Hoffmann, H; Dienemann, H

    2015-10-01

    Pulmonary cystic echinococcosis is a very rare disease in Germany. It is caused by the larvae of the dog tapeworm (echinococcus granulosus). The liver is the most affected organ, followed by the lungs. Surgery remains the main therapeutic approach for pulmonary CE. Whenever possible, parenchyma-preserving lung surgery should be preferred over anatomic lung resections. To ensure best therapeutic results, surgery needs to be performed under precise consideration of important infectiological aspects and patients should be treated in specialised centres based on interdisciplinary consensus. In addition to surgical aspects, this review summarises special infectiological features of this disease, which are crucial to the surgical approach. PMID:26351761

  12. Diversity of bacterial endophytes in 3 and 15 year-old grapevines of Vitis vinifera cv. Corvina and their potential for plant growth promotion and phytopathogen control.

    PubMed

    Andreolli, Marco; Lampis, Silvia; Zapparoli, Giacomo; Angelini, Elisa; Vallini, Giovanni

    2016-02-01

    This study represents the first investigation on ecology of endophytic bacteria isolated from 3 and 15 year-old vine stems of Vitis vinifera cv. Corvina. The analysis was performed by means of culture-dependent techniques. The obtained results showed that new grapevine endophytic genera are being discovered. Moreover, Bacilli and Actinobacteria are frequently isolated from 3 year-old plants, whereas Alpha- and Gamma- Proteobacteria classes are more prevalent in the 15 year-old plants. Shannon-Wiener (H) index and analysis of rarefaction curves revealed greater genus richness in young grapevine plants. Furthermore, results evidenced an increase of genotypic group number within specific genera (e.g., Rhizobium and Pantoea). Among isolated strains from 3 and 15 year-old stems, respectively, 34 and 39% produce siderophores; 22 and 15% secrete ammonia; 22 and 21% produce indole-3-acetic acid; 8.7 and 41% solubilize phosphate. Besides, two strains isolated from 15 year-old grapevines showed 1-aminocyclopropane-1-carboxylate deaminase activity. Antifungal activity analysis evidenced that two Bacillus strains possess growth antagonistic effect toward all the tested fungal strains. Therefore, the present study extends our knowledge of the diversity of the endophytic bacteria by providing new insights into the complexity of the grapevine microbiome. PMID:26805617

  13. Quality Control Analysis of Selected Aspects of Programs Administered by the Bureau of Student Financial Assistance. Error-Prone Model Derived from 1978-1979 Quality Control Study. Data Report. [Task 3.

    ERIC Educational Resources Information Center

    Saavedra, Pedro; Kuchak, JoAnn

    An error-prone model (EPM) to predict financial aid applicants who are likely to misreport on Basic Educational Opportunity Grant (BEOG) applications was developed, based on interviews conducted with a quality control sample of 1,791 students during 1978-1979. The model was designed to identify corrective methods appropriate for different types of

  14. Circadian Control of Global Transcription

    PubMed Central

    Li, Shujing; Zhang, Luoying

    2015-01-01

    Circadian rhythms exist in most if not all organisms on the Earth and manifest in various aspects of physiology and behavior. These rhythmic processes are believed to be driven by endogenous molecular clocks that regulate rhythmic expression of clock-controlled genes (CCGs). CCGs consist of a significant portion of the genome and are involved in diverse biological pathways. The transcription of CCGs is tuned by rhythmic actions of transcription factors and circadian alterations in chromatin. Here, we review the circadian control of CCG transcription in five model organisms that are widely used, including cyanobacterium, fungus, plant, fruit fly, and mouse. Comparing the similarity and differences in the five organisms could help us better understand the function of the circadian clock, as well as its output mechanisms adapted to meet the demands of diverse environmental conditions. PMID:26682214

  15. Aspects of Marine Ecology.

    ERIC Educational Resources Information Center

    Awkerman, Gary L.

    This publication is designed for use in standard science curricula to develop oceanologic manifestations of certain science topics. Included are teacher guides, student activities, and demonstrations to impart ocean science understanding, specifically, aspects of marine ecology, to high school students. The course objectives include the ability of…

  16. Sociological Aspects of Deafness.

    ERIC Educational Resources Information Center

    World Federation of the Deaf, Rome (Italy).

    Nine conference papers treat the sociological aspects of deafness. Included are "Individuals Being Deaf and Blind and Living with a Well Hearing Society" by A. Marx (German Federal Republic), "A Deaf Man's Experiences in a Hearing World" by A. B. Simon(U.S.A.), "Problem of Text Books and School Appliances for Vocational Education of Deaf Adults"…

  17. Medical Aspects of Surfing.

    ERIC Educational Resources Information Center

    Renneker, Mark

    1987-01-01

    The medical aspects of surfing include ear and eye injuries and sprains and strains of the lower back and neck, as well as skin cancer from exposure to the sun. Treatment, rehabilitation, and prevention of these problems are discussed. Surfing is recommended as part of an exercise program for reasonably healthy people. (Author/MT)

  18. A Randomized Controlled Trial of the First Step to Success Early Intervention: Demonstration of Program Efficacy Outcomes in a Diverse, Urban School District

    ERIC Educational Resources Information Center

    Walker, Hill M.; Seeley, John R.; Small, Jason; Severson, Herbert H.; Graham, Bethany A.; Feil, Edward G.; Serna, Loretta; Golly, Annemieke M.; Forness, Steven R.

    2009-01-01

    This article reports on a randomized controlled trial of the First Step to Success early intervention that was conducted over a 4-year period in Albuquerque Public Schools. First Step is a selected intervention for students in Grades 1 through 3 with externalizing behavior problems, and it addresses secondary prevention goals and objectives. It

  19. Towards a Better Understanding of the Relationship between Executive Control and Theory of Mind: An Intra-Cultural Comparison of Three Diverse Samples

    ERIC Educational Resources Information Center

    Shahaeian, Ameneh; Henry, Julie D.; Razmjoee, Maryam; Teymoori, Ali; Wang, Cen

    2015-01-01

    Previous research has consistently indicated that theory of mind (ToM) is associated with executive control in the preschool years. However, interpretation of this literature is limited by the fact that most studies have focused exclusively on urbanized Western cultural samples. Consequently, it is not clear whether the association between ToM and

  20. The Trojan Female Technique for pest control: a candidate mitochondrial mutation confers low male fertility across diverse nuclear backgrounds in Drosophila melanogaster.

    PubMed

    Dowling, Damian K; Tompkins, Daniel M; Gemmell, Neil J

    2015-10-01

    Pest species represent a major ongoing threat to global biodiversity. Effective management approaches are required that regulate pest numbers, while minimizing collateral damage to nontarget species. The Trojan Female Technique (TFT) was recently proposed as a prospective approach to biological pest control. The TFT draws on the evolutionary hypothesis that maternally inherited mitochondrial genomes are prone to the accumulation of male, but not female, harming mutations. These mutations could be harnessed to provide trans-generational fertility-based control of pest species. A candidate TFT mutation was recently described in the fruit fly, Drosophila melanogaster, which confers male-only sterility in the specific isogenic nuclear background in which it is maintained. However, applicability of the TFT relies on mitochondrial mutations whose male-sterilizing effects are general across nuclear genomic contexts. We test this assumption, expressing the candidate TFT-mutation bearing haplotype alongside a range of nuclear backgrounds and comparing its fertility in males, relative to that of control haplotypes. We document consistently lower fertility for males harbouring the TFT mutation, in both competitive and noncompetitive mating contexts, across all nuclear backgrounds screened. This indicates that TFT mutations conferring reduced male fertility can segregate within populations and could be harnessed to facilitate this novel form of pest control. PMID:26495040

  1. A Randomized Controlled Trial of the First Step to Success Early Intervention: Demonstration of Program Efficacy Outcomes in a Diverse, Urban School District

    ERIC Educational Resources Information Center

    Walker, Hill M.; Seeley, John R.; Small, Jason; Severson, Herbert H.; Graham, Bethany A.; Feil, Edward G.; Serna, Loretta; Golly, Annemieke M.; Forness, Steven R.

    2009-01-01

    This article reports on a randomized controlled trial of the First Step to Success early intervention that was conducted over a 4-year period in Albuquerque Public Schools. First Step is a selected intervention for students in Grades 1 through 3 with externalizing behavior problems, and it addresses secondary prevention goals and objectives. It…

  2. Towards a Better Understanding of the Relationship between Executive Control and Theory of Mind: An Intra-Cultural Comparison of Three Diverse Samples

    ERIC Educational Resources Information Center

    Shahaeian, Ameneh; Henry, Julie D.; Razmjoee, Maryam; Teymoori, Ali; Wang, Cen

    2015-01-01

    Previous research has consistently indicated that theory of mind (ToM) is associated with executive control in the preschool years. However, interpretation of this literature is limited by the fact that most studies have focused exclusively on urbanized Western cultural samples. Consequently, it is not clear whether the association between ToM and…

  3. The Trojan Female Technique for pest control: a candidate mitochondrial mutation confers low male fertility across diverse nuclear backgrounds in Drosophila melanogaster

    PubMed Central

    Dowling, Damian K; Tompkins, Daniel M; Gemmell, Neil J

    2015-01-01

    Pest species represent a major ongoing threat to global biodiversity. Effective management approaches are required that regulate pest numbers, while minimizing collateral damage to nontarget species. The Trojan Female Technique (TFT) was recently proposed as a prospective approach to biological pest control. The TFT draws on the evolutionary hypothesis that maternally inherited mitochondrial genomes are prone to the accumulation of male, but not female, harming mutations. These mutations could be harnessed to provide trans-generational fertility-based control of pest species. A candidate TFT mutation was recently described in the fruit fly, Drosophila melanogaster, which confers male-only sterility in the specific isogenic nuclear background in which it is maintained. However, applicability of the TFT relies on mitochondrial mutations whose male-sterilizing effects are general across nuclear genomic contexts. We test this assumption, expressing the candidate TFT-mutation bearing haplotype alongside a range of nuclear backgrounds and comparing its fertility in males, relative to that of control haplotypes. We document consistently lower fertility for males harbouring the TFT mutation, in both competitive and noncompetitive mating contexts, across all nuclear backgrounds screened. This indicates that TFT mutations conferring reduced male fertility can segregate within populations and could be harnessed to facilitate this novel form of pest control. PMID:26495040

  4. Sensory aspects of movement disorders

    PubMed Central

    Patel, Neepa; Jankovic, Joseph; Hallett, Mark

    2016-01-01

    Movement disorders, which include disorders such as Parkinson’s disease, dystonia, Tourette’s syndrome, restless legs syndrome, and akathisia, have traditionally been considered to be disorders of impaired motor control resulting predominantly from dysfunction of the basal ganglia. This notion has been revised largely because of increasing recognition of associated behavioural, psychiatric, autonomic, and other non-motor symptoms. The sensory aspects of movement disorders include intrinsic sensory abnormalities and the effects of external sensory input on the underlying motor abnormality. The basal ganglia, cerebellum, thalamus, and their connections, coupled with altered sensory input, seem to play a key part in abnormal sensorimotor integration. However, more investigation into the phenomenology and physiological basis of sensory abnormalities, and about the role of the basal ganglia, cerebellum, and related structures in somatosensory processing, and its effect on motor control, is needed. PMID:24331796

  5. Selenium. Nutritional, toxicologic, and clinical aspects.

    PubMed Central

    Fan, A. M.; Kizer, K. W.

    1990-01-01

    Despite the recent findings of environmental contamination, selenium toxicosis in humans is exceedingly rare in the United States, with the few known cases resulting from industrial accidents and an episode involving the ingestion of superpotent selenium supplements. Chronic selenosis is essentially unheard of in this country because of the typical diversity of the American diet. Nonetheless, because of the growing public interest in selenium as a dietary supplement and the occurrence of environmental selenium contamination, medical practitioners should be familiar with the nutritional, toxicologic, and clinical aspects of this trace element. PMID:2219873

  6. Selenium. Nutritional, toxicologic, and clinical aspects

    SciTech Connect

    Fan, A.M.; Kizer, K.W. )

    1990-08-01

    Despite the recent findings of environmental contamination, selenium toxicosis in humans is exceedingly rare in the United States, with the few known cases resulting from industrial accidents and an episode involving the ingestion of superpotent selenium supplements. Chronic selenosis is essentially unheard of in this country because of the typical diversity of the American diet. Nonetheless, because of the growing public interest in selenium as a dietary supplement and the occurrence of environmental selenium contamination, medical practitioners should be familiar with the nutritional, toxicologic, and clinical aspects of this trace element. 53 references.

  7. Wind-Tunnel Investigation at Subsonic and Supersonic Speeds of a Fighter Model Employing a Low-Aspect-Ratio Unswept Wing and a Horizontal Tail Mounted Well Above the Wing Plane - Longitudinal Stability and Control

    NASA Technical Reports Server (NTRS)

    Smith, Williard G.

    1954-01-01

    Experimental results showing the static longitudinal-stability and control characteristics of a model of a fighter airplane employing a low-aspect-ratio unswept wing and an all-movable horizontal tail are presented. The investigation was made over a Mach number range from 0.60 to 0.90 and from 1.35 to 1.90 at a constant Reynolds number of 2.40 million, based on the wing mean aerodynamic chord. Because of the location of the horizontal tail at the tip of the vertical tail, interference was noted between the vertical tail and the horizontal tail and between the wing and the horizontal tail. This interference produced a positive pitching-moment coefficient at zero lift throughout the Mach number range of the tests, reduced the change in stability with increasing lift coefficient of the wing at moderate lift coefficients in the subsonic speed range, and reduced the stability at low lift coefficients at high supersonic speeds. The lift and pitching-moment effectiveness of the all movable tail was unaffected by the interference effects and was constant throughout the lift-coefficient range of the tests at each Mach number except 1.90.

  8. Psychosocial Aspects of Obesity.

    PubMed

    Beck, Amy R

    2016-01-01

    This article is the sixth in a series of the comorbidities of childhood obesity and reviews psychosocial aspects with a focus on weight-based victimization and discrimination stemming from weight bias and stigma. Outcomes from these bullying and discriminatory experiences are pervasive and impact youth across all settings, including school. Lastly, this article provides recommendations on how to reduce bias and stigma to better serve these students in the school environment. PMID:26739931

  9. [Rheumatoid arthritis: psychosomatic aspects].

    PubMed

    Grekhov, R A; Kharchenko, S A; Suleĭmanova, G P; Aleksandrov, A V; Zborovskiĭ, A B

    2012-01-01

    The review considers the results of studies of the psychosomatic aspects of rheumatoid arthritis (RA), which have been published in the past 5 years. In particular, there is evidence for the impact of chronic pain on the psychological status of patients with RA, for that of the disease on quality of life in the patients, their sociopsychological and interpersonal relationships; trials of the efficiency of additional treatment options for RA are given. PMID:23480004

  10. Aspects of B physics

    SciTech Connect

    Gaillard, M.K.

    1987-10-14

    Various aspects of weak decays are commented on. Probing of the standard model and of phenomena beyond the standard model are discussed, followed by a theoretical view of B mesons and some experimental observations on B mesons. The point is made that any data on B decay would be interesting in that it would provide powerful new constraints in analyses of the standard model and extensions thereof. (LEW)

  11. Rectenna session: Micro aspects

    NASA Technical Reports Server (NTRS)

    Gutmann, R. J.

    1980-01-01

    Two micro aspects of rectenna design are discussed: evaluation of the degradation in net rectenna RF to DC conversion efficiency due to power density variations across the rectenna (power combining analysis) and design of Yagi-Uda receiving elements to reduce rectenna cost by decreasing the number of conversion circuits (directional receiving elements). The first of these involves resolving a fundamental question of efficiency potential with a rectenna, while the second involves a design modification with a large potential cost saving.

  12. Teaching to Diversity: Creating Compassionate Learning Communities for Diverse Elementary School Students

    ERIC Educational Resources Information Center

    Katz, Jennifer; Porath, Marion

    2011-01-01

    Emotional and behavioral outcomes of the Respecting Diversity (RD) program, a social and emotional learning (SEL) intervention to develop self-awareness, self-respect and respect for diverse others, were investigated with 218 students in Grades four to seven and their teachers. Intervention and control groups were assessed pre and post…

  13. Multilingual Aspects of Fluency Disorders. Communication Disorders across Languages

    ERIC Educational Resources Information Center

    Howell, Peter; Van Borsel, John

    2011-01-01

    This book contains contributions by scholars working on diverse aspects of speech who bring their findings to bear on the practical issue of how to treat stuttering in different language groups and in multilingual speakers. The book considers classic issues in speech production research, as well as whether regions of the brain that are affected in…

  14. Multilingual Aspects of Fluency Disorders. Communication Disorders across Languages

    ERIC Educational Resources Information Center

    Howell, Peter; Van Borsel, John

    2011-01-01

    This book contains contributions by scholars working on diverse aspects of speech who bring their findings to bear on the practical issue of how to treat stuttering in different language groups and in multilingual speakers. The book considers classic issues in speech production research, as well as whether regions of the brain that are affected in

  15. Everyday Spirituality: An Aspect of the Holistic Curriculum in Action

    ERIC Educational Resources Information Center

    Bone, Jane; Cullen, Joy; Loveridge, Judith

    2007-01-01

    Early childhood education in Aotearoa New Zealand includes different philosophical perspectives, may be part of the public or private sector and aims to be inclusive and holistic. The early childhood curriculum, Te Whariki, supports these aims. Aspects of the curriculum that are holistic may be conceptualized in diverse ways and this qualitative

  16. Everyday Spirituality: An Aspect of the Holistic Curriculum in Action

    ERIC Educational Resources Information Center

    Bone, Jane; Cullen, Joy; Loveridge, Judith

    2007-01-01

    Early childhood education in Aotearoa New Zealand includes different philosophical perspectives, may be part of the public or private sector and aims to be inclusive and holistic. The early childhood curriculum, Te Whariki, supports these aims. Aspects of the curriculum that are holistic may be conceptualized in diverse ways and this qualitative…

  17. Diversity of endophytic fungal community of cacao (Theobroma cacao L.) and biological control of Crinipellis perniciosa, causal agent of Witches' Broom Disease

    PubMed Central

    2005-01-01

    The basidiomycete fungus Crinipellis perniciosa (Stahel) Singer is the causal agent of Witches' Broom Disease of Cacao (Theobroma cacao L.) which is the main factor limiting cacao production in the Americas. Pod losses of up to 90% are experienced in affected areas as evidenced by the 50% drop in production in Bahia province, Brazil following the arrival of the C. perniciosa in the area in 1989. The disease has proven particularly difficult to control and many farmers in affected areas have given up cacao cultivation. In order to evaluate the potential of endophytes as a biological control agent of this phytopathogen, the endophytic fungal community of resistant and susceptible cacao plants as well as affected branches was studied between 2001 and 2002. The fungal community was identified by morphological traits and rDNA sequencing as belonging to the genera Acremonium, Blastomyces, Botryosphaeria, Cladosporium, Colletotrichum, Cordyceps, Diaporthe, Fusarium, Geotrichum, Gibberella, Gliocladium, Lasiodiplodia, Monilochoetes, Nectria, Pestalotiopsis, Phomopsis, Pleurotus, Pseudofusarium, Rhizopycnis, Syncephalastrum, Trichoderma, Verticillium and Xylaria. These fungi were evaluated both in vitro and in vivo by their ability to inhibit C. perniciosa. Among these, some were identified as potential antagonists, but only one fungus (Gliocladium catenulatum) reduced the incidence of Witches' Broom Disease in cacao seedlings to 70%. PMID:15951847

  18. Treatment of Depressive Symptoms in Diverse, Rural and Vulnerable Older Adults

    PubMed Central

    Scogin, Forrest R.; Moss, Kathryn; Harris, Grant M.; Presnell, Andrew H.

    2013-01-01

    BACKGROUND/OBJECTIVES We examined the effects of home-delivered CBT on depressive symptoms among rural, diverse and vulnerable older adults. Furthermore, we differentiated depression into its two salient aspects: psychological and somatic. METHOD Data came from a randomized controlled experiment of cognitive-behavior therapy (CBT) on 134 individuals residing in rural Alabama. RESULTS CBT resulted in significantly lower depressive symptom severity scores. When depressive symptoms were categorized as psychological or somatic, CBT was found to significantly improve the former but not the latter. Notably, there was a trend toward somatic symptom improvement. CONCLUSION CBT can be an effective treatment for depression in a hard-to-reach group of older adults. Home-delivery affords advantages but is also an expensive delivery modality. Diverse older adults responded to the CBT intervention. PMID:23893503

  19. Diversity and leadership in a changing world.

    PubMed

    Eagly, Alice H; Chin, Jean Lau

    2010-04-01

    Scholars of leadership have infrequently addressed the diversity of leaders and followers in terms of culture, gender, race and ethnicity, or sexual orientation. This omission has weakened the ability of research and theory to address some of the most provocative aspects of contemporary leadership, including (a) the limited access of individuals from diverse identity groups to leadership roles; (b) the shaping of leaders' behavior by their dual identities as leaders and members of gender, racial, ethnic, or other identity groups; and (c) the potential of individuals from groups formerly excluded from leadership roles to provide excellent leadership because of their differences from traditional leaders. In addressing such issues, we argue that the joining of the two bodies of theory and research--one pertaining to leadership and the other to diversity--enriches both domains of knowledge and provides guidelines for optimizing leadership in contemporary organizations and nations. PMID:20350020

  20. High-aspect-ratio wings

    NASA Technical Reports Server (NTRS)

    Peterson, John B., Jr.

    1988-01-01

    High-aspect-ratio aircraft include most transport aircraft such as commercial and military transports, business aircraft, and cargo aircraft. Generally, these types of aircraft are designed to cruise over a narrow range of lift coefficients and Mach numbers in the performance of their mission. Emphasis is therefore placed on the cruise performance of transport aircraft and every effort is made to obtain accurate wind-tunnel data to use as a basis for prediction of full-scale cruise performance. However, off-cruise performance is also important and methods were developed for extrapolating wind-tunnel data on buffet and flutter at transonic speed. Transport-type aircraft were tested extensively in various wind tunnels around the world and many different test techniques were developed to simulate higher Reynolds numbers. Methods developed for one tunnel may not be applicable to another tunnel because of differences in size, Reynolds number capability, running time, and test objectives. Many of the methods of boundary-layer control developed in two-dimensional airfoil testing can be applied in tests of transport configurations, but sometimes the three-dimensional flow fields that develop on tranpsort aircraft can make application of the two-dimensional methods difficult or impossible. The discussion is intended to be a representative, but not exhaustive, survey of the various methods of high Reynolds number simulation in the testing of high-aspect-ratio aircraft.

  1. Diversity and factors controlling widespread occurrence of syn-rift Ladinian microbialites in the western Tethys (Triassic Catalan Basin, NE Spain)

    NASA Astrophysics Data System (ADS)

    Mercedes-Martn, Ramon; Arenas, Concha; Salas, Ramon

    2014-11-01

    The fault-block carbonate ramps of the Ladinian (Middle Triassic) Catalan Basin hosted a wide variety of microbial deposits which formed during a syn-rift stage. Stratigraphical and sedimentological analyses of these microbialites allow us to reconstruct two depositional models for such microbial deposits. Moreover new insights into the interplay between the intrinsic and extrinsic factors that controlled the widespread development of these microbialites are provided. Stromatolites, ooidal-muddy microbial laminites and thrombolites were analyzed on the basis of their geometry, lamination and textural attributes. These microbialites are distributed over two Transgressive-Regressive sequences and coexisted during the Fassanian (Early Ladinian) regressive stage. Later, stromatolites and ooidal-muddy microbial laminites developed during the Longobardian (Late Ladinian) transgressive stage. Three types of lamina couplets reflect distinct accretion processes linked to water chemistry, sediment supply and hydrodynamic conditions. Thrombolite textures were produced by accretionary, binding and encrusting processes (microbially mediated) and pervasive cementation. The widespread occurrence of microbial deposits is explained as a consequence of a biogeochemical cascade of events (e.g., anoxic/dysoxic seawater conditions, volcanic activity, upwelling of alkaline waters, nutrient concentrations, and microbial blooms), which promoted favorable conditions for microbial growth in the Tethys during the Ladinian. Furthermore, in the Catalan Basin, syn-rift fault induced subsidence and local water energy gradients exerted an essential role in the distribution of the three types of microbialites through space and time. Thrombolites were prone to grow in the hanging wall block of a half-graben (subtidal conditions), whereas stromatolites and ooidal-muddy microbial laminites flourished preferably in a foot wall block setting (intertidal-shallow subtidal conditions). However, the fact that thrombolites exhibit abundant botryoidal and isopachous fibrous marine cements, corrosion and significant microbial evidence allow us to hypothesize about the relationship between thrombolite occurrence and hydrothermal fault-controlled fluid circulation during the Triassic rifting. The two depositional models here proposed constitute a step forward the understanding of the platform-to-basin microbialite heterogeneity during the Ladinian. Furthermore this work sheds new light on the mechanisms that likely promoted microbialite development during a period of major ecological restructuration and complex oceanographic conditions.

  2. A Diversity Visionary

    ERIC Educational Resources Information Center

    Smith, Susan

    2012-01-01

    Today's chief diversity officer could be tomorrow's university president, says Dr. Damon Williams. The author profiles Damon Williams who shines as sought-after expert on issues surrounding higher education inclusion. As head of a diversity division with an eight-figure budget at Wisconsin's flagship state university, Williams oversees four

  3. Diversity in Leadership

    ERIC Educational Resources Information Center

    Beer, Janet

    2015-01-01

    This paper presents a lecture given at the 17th Annual Lecture of the Association of University Administrators (AUA). The subject of the lecture is equality and diversity in higher education (HE) leadership, or possibly the absence of equality and diversity. The author focuses on what can be done to ensure that capable women enter HE leadership…

  4. Diversity in Leadership

    ERIC Educational Resources Information Center

    Beer, Janet

    2015-01-01

    This paper presents a lecture given at the 17th Annual Lecture of the Association of University Administrators (AUA). The subject of the lecture is equality and diversity in higher education (HE) leadership, or possibly the absence of equality and diversity. The author focuses on what can be done to ensure that capable women enter HE leadership

  5. Diversity and the Academy

    ERIC Educational Resources Information Center

    Parker, Jan

    2007-01-01

    This essay comes from pondering the relationship, queried in the Call for this Special Issue, between the "language of diversity" and the "embracing of different forms of knowledge and ways of knowing" in the university. The issue of diversity is usually a sociological rather than an epistemological one--the access to and inclusion in higher

  6. Dissecting Diversity Part II

    ERIC Educational Resources Information Center

    Matthews, Frank

    2005-01-01

    This article presents "Dissecting Diversity, Part II," the conclusion of a wide-ranging two-part roundtable discussion on diversity in higher education. The participants were as follows: Lezli Baskerville, J.D., President and CEO of the National Association for Equal Opportunity (NAFEO); Dr. Gerald E. Gipp, Executive Director of the American

  7. Pasture diversity and management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the economic importance of pastures in the northeastern United States, not much is known about their ecology, including taxonomic and functional diversity. This factsheet presents results from a 1998-2005 survey of pastures on 44 farms from Maine to Maryland. Pastures are quite diverse; the ...

  8. Issue Brief on Diversity

    ERIC Educational Resources Information Center

    Division on Developmental Disabilities, Council for Exceptional Children (NJ1), 2013

    2013-01-01

    During the past year, the Diversity Committee of the Division of Developmental Disabilities (DDD) Board worked with the Board and the Issues Committee Chair to develop an issue brief addressing diversity, its impact on the membership and the wider community that is served by the work of DDD, resulting in recommendations that will influence policy

  9. Diversity and Social Cohesion

    ERIC Educational Resources Information Center

    Pagani, Camilla

    2014-01-01

    The issue of diversity, in its broadest sense, is discussed here in its relation to social cohesion, cross-cultural relations, ingroup-outgroup relations and educational interventions. The main thesis of the paper is that real social cohesion in an ingroup rests on the acknowledgment of and the dialog with the diversities of the members of the

  10. Why Diversity Matters

    ERIC Educational Resources Information Center

    Bollinger, Lee C.

    2007-01-01

    In this article, the author provides insight on the issue of diversity in higher education. The author asserts that diversity--one of the great strengths of American education--is under siege today. At the elementary- and secondary-school levels, resegregation is making it exceedingly difficult for minority students to get the resources that

  11. Evolution & Diversity in Plants.

    ERIC Educational Resources Information Center

    Pearson, Lorentz C.

    1988-01-01

    Summarizes recent findings that help in understanding how evolution has brought about the diversity of plant life that presently exists. Discusses basic concepts of evolution, diversity and classification, the three-line hypothesis of plant evolution, the origin of fungi, and the geologic time table. Included are 31 references. (CW)

  12. Voices for Diversity.

    ERIC Educational Resources Information Center

    Future Teacher, 1995

    1995-01-01

    Prominent Americans were asked to reflect on the diversity challenge facing America's teacher workforce. The following leaders from several fields voiced their support of teachers and their beliefs America needs more diverse and culturally responsive teachers: (1) Mary Hatwood Futrell, President of Education International; (2) Carol Moseley-Braun,…

  13. Past Planktonic Diversity

    NASA Astrophysics Data System (ADS)

    Rufino, M. M.; Salgueiro, E.; Voelker, A. H. L.; Abrantes, F. F. G.

    2014-12-01

    Planktonic organisms have been extensively used in paleoceanographic studies as proxies for most marine environmental variables (temperature, salinity, currents, frontal zones, upwelling, etc.), both directly by species occurrences and indirectly through particular chemical components produced (e.g. Mg/Ca, stable isotopes, alkanones). In 1965 Stehli pioneered by suggesting the use of planktonic organisms diversity to decipher ancient oceanic circulation, instead of the traditional approaches based on particular indicator species or assemblages composition (transfer functions). The use of species diversity has two main advantages. First, it is not restricted to a temporal epoch where the species existed and second, it does not assume that the species ecology is the same as in the present. In the current work, we compare planktonic organisms diversity on the Atlantic Ocean, obtained from surface samples, with the main satellite measured oceanographic variables, i.e. SST (Sea Surface Temperature), CHL (as an indicator of primary productivity) and the main currents in the area. Three indices were used to quantify diversity: Shannon-Weaver diversity (H), specific richness (S) and Hulbert's probability of interspecific encounter index of species evenness (PIE). Diversity was then modelled spatially using geostatistical tools at two scales: Atlantic Ocean oceanographic scale and the Iberian margin regional scale. The main conclusions will then be used to interpret measured down core diversity, on a paleo perspective. This work will understand how did diversity reacted to major climatic events, and how long it took to recover - system resilience.

  14. Diversity Training Programs

    Cancer.gov

    The Center for Cancer Training (CCT) Intramural Diversity Workforce Branch (IDWB) attracts, recruits, and fosters a community of scientists from diverse backgrounds, and supports them through onboarding and mentoring. The branch also develops and implements activities and programs to create a lasting culture of inclusion.

  15. Global Diversity and Leadership.

    ERIC Educational Resources Information Center

    Ruiz, Art

    2003-01-01

    Argues that global diversity has become a business imperative in today's business climate. Global diversity is of core importance even for companies that are considered domestic. Suggests community colleges need help in understanding their customer base and their shifting values in order to meet their needs and win customer loyalty. (NB)

  16. Dissecting Diversity Part II

    ERIC Educational Resources Information Center

    Matthews, Frank

    2005-01-01

    This article presents "Dissecting Diversity, Part II," the conclusion of a wide-ranging two-part roundtable discussion on diversity in higher education. The participants were as follows: Lezli Baskerville, J.D., President and CEO of the National Association for Equal Opportunity (NAFEO); Dr. Gerald E. Gipp, Executive Director of the American…

  17. Soybean Molecular Genetic Diversity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A history of the various DNA marker types used in the assessment of molecular genetic diversity in soybean [Glycine max (L.) Merr.] is followed by a description of a number of studies on the assessment of genetic diversity. These studies include a review of reports on 1) the quantification and comp...

  18. Diversity and Social Cohesion

    ERIC Educational Resources Information Center

    Pagani, Camilla

    2014-01-01

    The issue of diversity, in its broadest sense, is discussed here in its relation to social cohesion, cross-cultural relations, ingroup-outgroup relations and educational interventions. The main thesis of the paper is that real social cohesion in an ingroup rests on the acknowledgment of and the dialog with the diversities of the members of the…

  19. Psychological aspects of headache

    PubMed Central

    Bridges, P. K.

    1971-01-01

    Headache is one of the most common symptoms encountered in clinical practice. Its conceptual problems are those of pain in general and some of the theories concerning pain, especially those attempting to relate psychological and physical aspects, are considered. The classifications which have been suggested for headaches associated with emotional causes are described and it is shown that these are of limited clinical value. Some of the psychogenic causes of headache are considered and the associations of the symptom with various psychiatric illnesses are described. Headache is especially likely to be found with depressive illnesses. The treatments for various psychological types of headache are reviewed.

  20. 49 CFR 236.703 - Aspect.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions 236.703 Aspect. The appearance of a roadway signal conveying an indication as viewed from the direction of an approaching train; the appearance of a cab signal conveying an indication as viewed by an observer in the cab....

  1. 49 CFR 236.703 - Aspect.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions 236.703 Aspect. The appearance of a roadway signal conveying an indication as viewed from the direction of an approaching train; the appearance of a cab signal conveying an indication as viewed by an observer in the cab....

  2. 49 CFR 236.703 - Aspect.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions 236.703 Aspect. The appearance of a roadway signal conveying an indication as viewed from the direction of an approaching train; the appearance of a cab signal conveying an indication as viewed by an observer in the cab....

  3. 49 CFR 236.703 - Aspect.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions 236.703 Aspect. The appearance of a roadway signal conveying an indication as viewed from the direction of an approaching train; the appearance of a cab signal conveying an indication as viewed by an observer in the cab....

  4. 49 CFR 236.703 - Aspect.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions 236.703 Aspect. The appearance of a roadway signal conveying an indication as viewed from the direction of an approaching train; the appearance of a cab signal conveying an indication as viewed by an observer in the cab....

  5. Clinical aspects of cervical insufficiency

    PubMed Central

    Lotgering, Frederik K

    2007-01-01

    Fetal loss is a painful experience. A history of second or early third trimester fetal loss, after painless dilatation of the cervix, prolapse or rupture of the membranes, and expulsion of a live fetus despite minimal uterine activity, is characteristic for cervical insufficiency. In such cases the risk of recurrence is high, and a policy of prophylactic cerclage may be safer than one of serial cervical length measurements followed by cerclage, tocolysis and bed rest in case of cervical shortening or dilatation. In low risk cases, however, prophylactic cerclage is not useful. There is a need for more basic knowledge of cervical ripening, objective assessment of cervical visco-elastic properties, and randomized controlled trials of technical aspects of cervical cerclage (e.g. suturing technique). PMID:17570161

  6. Revisiting Iron-based Paleoredox Proxies in Light of Diverse Primary and Secondary Controls and Overprints: A Story of Cautious Optimism

    NASA Astrophysics Data System (ADS)

    Lyons, T. W.; Planavsky, N. J.; Reinhard, C.; Raiswell, R.

    2012-12-01

    Iron proxies are among the favored tracers for oxygen conditions in the ancient ocean. They are based on relationships among total Fe content and mineral phases that are reactive to hydrogen sulfide to form pyrite on early diagenetic time scales, and their utility has increased in recent years with a growing understanding of their mechanistic underpinnings. Threshold values defined in modern fine-grained silciciclastic settings allow us to distinguish among oxic settings and those that were anoxic and either ferruginous or euxinic. However, the relative ease of generating these data by sequential extraction and the availability of data thresholds defined via studies in the modern ocean also carry a risk. With increasing frequency these methods are applied in studies of Earth history without careful consideration of confounding primary and secondary controls that mirror spatial and temporal gradients in sedimentation rate, rock type, burial alteration, basin scale and corresponding Fe inputs and source-sink relationships, among other concerns. With careful consideration, however, these spatiotemporal heterogeneities and their impacts on the Fe proxies can be dealt with unambiguously and can even become strengths as refined mechanistic perspectives yield new paleoenvironmental insight. Here we will explore the impacts of various primary and secondary controls on the proxies and their abilities to resolve depositional redox conditions with confidence. The sedimentological context must be considered carefullyfor example, rapid sedimentation and sediment reworking can mute the Fe expressions of anoxia. We will also emphasize the importance of using shales in these assessments simply because the modern calibrations were performed on shale analogs. We will explore how the efficacy of the proxies and our mechanistic and mass balance perspectives, and specifically the broadest utility of the Black Sea analog, can be compromised as depositional scales shift from relatively small restricted basins to large portions of the ocean that include inputs of hydrothermal Fe via mid-ocean ridges. In all this, we discourage unquestioned use of universal threshold values, such as for reactive-to-total Fe. These boundaries can change across depositional gradients and, most importantly, can change with time via post-depositional mineralogical transformations, including metamorphism and weathering. We caution strongly against use of the threshold values for anoxia and euxinia in ways that have become too prescriptive and thus blind to the potential for exceptions and the risks of over-interpretation. Finally, these are proxies for local redox, and so extrapolations to large-scale conditions require extreme care. Despite these cautions, the take-home message will be optimistic, clarifying the importance of an integrated approach that employs the full suite of iron approaches and confirming that traditional and modified extractions do in fact compensate for secondary mineral alteration and primary variability. In the end, effective applications only come by way of a broad and rigorously mechanistic vantage.

  7. Assessment of Immune Interference, Antagonism and Diversion following Human Immunization with Bi-Allelic Blood-Stage Malaria Viral Vectored Vaccines and Controlled Malaria Infection

    PubMed Central

    Elias, Sean C.; Collins, Katharine A.; Halstead, Fenella D.; Choudhary, Prateek; Bliss, Carly M.; Ewer, Katie J.; Sheehy, Susanne H.; Duncan, Christopher J. A.; Biswas, Sumi; Hill, Adrian V. S.; Draper, Simon J.

    2012-01-01

    Overcoming antigenic variation is one of the major challenges in the development of an effective vaccine against Plasmodium falciparum, a causative agent of human malaria. Inclusion of multiple antigen variants in subunit vaccine candidates is one strategy that has aimed to overcome this problem for the leading blood-stage malaria vaccine targets, merozoite surface protein 1 (MSP1) and apical membrane antigen 1 (AMA1). However previous studies, utilizing malaria antigens, have concluded that inclusion of multiple allelic variants, encoding altered peptide ligands (APL), in such a vaccine may be detrimental to both the priming and in vivo re-stimulation of antigen-experienced T cells. Here we analyze the T cell responses to two alleles of MSP1 and AMA1 induced by vaccination of malaria-nave adult volunteers with bi-valent viral vectored vaccine candidates. We show a significant bias to the 3D7/MAD20 allele compared to the Wellcome allele for the 33kDa region of MSP1, but not for the 19kDa fragment or the AMA1 antigen. Whilst this bias could be caused by immune interference at priming, the data dont support a significant role for immune antagonism during memory T cell re-stimulation, despite observation of the latter at a minimal epitope level in vitro. A lack of class I HLA epitopes in the Wellcome allele that are recognized by vaccinated volunteers may in fact contribute to the observed bias. We also show that controlled infection with 3D7 strain P. falciparum parasites neither boosts existing 3D7-specific T cell responses nor appears to immune divert cellular responses towards the Wellcome allele. PMID:23293353

  8. The role of diverse instruction in conceptual change.

    PubMed

    Hayes, Brett K; Goodhew, Alison; Heit, Evan; Gillan, Joanna

    2003-12-01

    This study examined how a fundamental principle of induction and scientific reasoning, information diversity, could be used to promote change in children's mental models of the earth's shape. Six-year-old children (N=132) were randomly allocated to a control or to one of two training conditions. Some training groups received instruction that simultaneously challenged children's beliefs concerning (a) why the earth appears flat to a surface observer and (b) the role of gravity. Others received instruction that repeatedly challenged only one of these beliefs. An adaptation of the Vosniadou and Brewer (1992, Cognitive Psychology 24, 535-585) protocol for identifying mental models of the earth was administered before and after instruction. Both instruction methods produced increases in factual knowledge. Only children receiving instruction about two core beliefs, however, showed an increased rate of acceptance of a spherical earth model at posttest. The findings show that instruction that challenges diverse aspects of children's nave scientific beliefs is more likely to produce conceptual change. PMID:14623212

  9. Beyond the Diversity Crisis Model: Decentralized Diversity Planning and Implementation

    ERIC Educational Resources Information Center

    Williams, Damon A.

    2008-01-01

    This article critiques the diversity crises model of diversity planning in higher education and presents a decentralized diversity planning model. The model is based on interviews with the nation's leading diversity officers, a review of the literature and the authors own experiences leading diversity change initiatives in higher education. The

  10. Regulatory aspects on nanomedicines.

    PubMed

    Sainz, Vanessa; Conniot, Joo; Matos, Ana I; Peres, Carina; Zupan I, Eva; Moura, Liane; Silva, Liana C; Florindo, Helena F; Gaspar, Rogrio S

    2015-12-18

    Nanomedicines have been in the forefront of pharmaceutical research in the last decades, creating new challenges for research community, industry, and regulators. There is a strong demand for the fast development of scientific and technological tools to address unmet medical needs, thus improving human health care and life quality. Tremendous advances in the biomaterials and nanotechnology fields have prompted their use as promising tools to overcome important drawbacks, mostly associated to the non-specific effects of conventional therapeutic approaches. However, the wide range of application of nanomedicines demands a profound knowledge and characterization of these complex products. Their properties need to be extensively understood to avoid unpredicted effects on patients, such as potential immune reactivity. Research policy and alliances have been bringing together scientists, regulators, industry, and, more frequently in recent years, patient representatives and patient advocacy institutions. In order to successfully enhance the development of new technologies, improved strategies for research-based corporate organizations, more integrated research tools dealing with appropriate translational requirements aiming at clinical development, and proactive regulatory policies are essential in the near future. This review focuses on the most important aspects currently recognized as key factors for the regulation of nanomedicines, discussing the efforts under development by industry and regulatory agencies to promote their translation into the market. Regulatory Science aspects driving a faster and safer development of nanomedicines will be a central issue for the next years. PMID:26260323

  11. Scuticociliatosis and its recent prophylactic measures in aquaculture with special reference to South Korea Taxonomy, diversity and diagnosis of scuticociliatosis: Part I Control strategies of scuticociliatosis: Part II.

    PubMed

    Harikrishnan, Ramasamy; Balasundaram, Chellam; Heo, Moon-Soo

    2010-07-01

    Scuticociliatosis caused by about 20 species belonging to the Phylum Ciliophora has been recognized as an emerging problem inflicting significant economic loss in aquaculture industry in the world. Among these Philasterides dicentrarchi, Miamiensis avidus, and Uronema marinum are the three species responsible for scuticociliatosis in olive flounder farms of South Korea. Some of the parasites living or scavenger ciliates also have become parasites of aquaculture fish. The major clinico-pathological manifestations of scuticociliatosis infected fishes are anemia, weight loss, dark coloration, enteritis, excessive body mucus, yellowish intestinal mucus, loss of scales, hemorrhagic and/or bleached spots on the skin, and dermal necrotic lesions that finally destroy tissues lead to high mortalities. Affected fish exhibit organ-specific pathological changes in the brain, eyes, muscle, gills, liver, kidney, intestine, and stomach that lead to severe mortality. At present, farmers in South Korea manage scuticociliatosis by using therapeutic measures, such as application of antibiotics like oxytetracycline, gentamycine, tetracycline, amoxycililin, and cefazolin and chemicals, such as formalin, hydrogen peroxide, malachite green, and jenoclean at a concentration of 350 +/- 150 ppm. However till date, no systematic scientific study has been conducted under field condition on the efficacy of these management measures. Under laboratory condition the ciliate can be effectively controlled with the antibiotics and chemicals while on the host, but on entering the host no systemic chemotherapeutic treatment has been yet proven effective. Furthermore the indiscriminate uses of harmful chemicals in aquaculture are increasingly becoming a cause of concern. Recently formalin and malachite green, the most widely used chemicals have been banned in food fish production by FDA as not consumer friendly and being carcinogenic respectively. Vaccines and immunostimulants can induce good immune response and protect against scuticociliatosis as it has been proved in the case of freshwater Ich. Now a days a number of probiotics and herbal formulations are in use against freshwater bacterial and fungal diseases, while, little information is available regarding the different prophylactic measures against marine scuticociliatosis. This review attempts to provide information on the various prophylaxic measures practiced against scuticociliatosis with special reference to olive flounder farms in South Korea. PMID:20211263

  12. Algorithms for high aspect ratio oriented triangulations

    NASA Technical Reports Server (NTRS)

    Posenau, Mary-Anne K.

    1995-01-01

    Grid generation plays an integral part in the solution of computational fluid dynamics problems for aerodynamics applications. A major difficulty with standard structured grid generation, which produces quadrilateral (or hexahedral) elements with implicit connectivity, has been the requirement for a great deal of human intervention in developing grids around complex configurations. This has led to investigations into unstructured grids with explicit connectivities, which are primarily composed of triangular (or tetrahedral) elements, although other subdivisions of convex cells may be used. The existence of large gradients in the solution of aerodynamic problems may be exploited to reduce the computational effort by using high aspect ratio elements in high gradient regions. However, the heuristic approaches currently in use do not adequately address this need for high aspect ratio unstructured grids. High aspect ratio triangulations very often produce the large angles that are to be avoided. Point generation techniques based on contour or front generation are judged to be the most promising in terms of being able to handle complicated multiple body objects, with this technique lending itself well to adaptivity. The eventual goal encompasses several phases: first, a partitioning phase, in which the Voronoi diagram of a set of points and line segments (the input set) will be generated to partition the input domain; second, a contour generation phase in which body-conforming contours are used to subdivide the partition further as well as introduce the foundation for aspect ratio control, and; third, a Steiner triangulation phase in which points are added to the partition to enable triangulation while controlling angle bounds and aspect ratio. This provides a combination of the advancing front/contour techniques and refinement. By using a front, aspect ratio can be better controlled. By using refinement, bounds on angles can be maintained, while attempting to minimize the number of Steiner points.

  13. Climate, energy and diversity

    PubMed Central

    Clarke, Andrew; Gaston, Kevin J

    2006-01-01

    In recent years, a number of species–energy hypotheses have been developed to explain global patterns in plant and animal diversity. These hypotheses frequently fail to distinguish between fundamentally different forms of energy which influence diversity in dissimilar ways. Photosynthetically active radiation (PAR) can be utilized only by plants, though their abundance and growth rate is also greatly influenced by water. The Gibbs free energy (chemical energy) retained in the reduced organic compounds of tissue can be utilized by all heterotrophic organisms. Neither PAR nor chemical energy influences diversity directly. Both, however, influence biomass and/or abundance; diversity may then increase as a result of secondary population dynamic or evolutionary processes. Temperature is not a form of energy, though it is often used loosely by ecologists as a proxy for energy; it does, however, influence the rate of utilization of chemical energy by organisms. It may also influence diversity by allowing a greater range of energetic lifestyles at warmer temperatures (the metabolic niche hypothesis). We conclude that there is no single species/energy mechanism; fundamentally different processes link energy to abundance in plants and animals, and diversity is affected secondarily. If we are to make progress in elucidating these mechanisms, it is important to distinguish climatic effects on species' distribution and abundance from processes linking energy supply to plant and animal diversity. PMID:16928626

  14. Dinosaur diversity and the rock record.

    PubMed

    Barrett, Paul M; McGowan, Alistair J; Page, Victoria

    2009-07-22

    Palaeobiodiversity analysis underpins macroevolutionary investigations, allowing identification of mass extinctions and adaptive radiations. However, recent large-scale studies on marine invertebrates indicate that geological factors play a central role in moulding the shape of diversity curves and imply that many features of such curves represent sampling artefacts, rather than genuine evolutionary events. In order to test whether similar biases affect diversity estimates for terrestrial taxa, we compiled genus-richness estimates for three Mesozoic dinosaur clades (Ornithischia, Sauropodomorpha and Theropoda). Linear models of expected genus richness were constructed for each clade, using the number of dinosaur-bearing formations available through time as a proxy for the amount of fossiliferous rock outcrop. Modelled diversity estimates were then compared with observed patterns. Strong statistically robust correlations demonstrate that almost all aspects of ornithischian and theropod diversity curves can be explained by geological megabiases, whereas the sauropodomorph record diverges from modelled predictions and may be a stronger contender for identifying evolutionary signals. In contrast to other recent studies, we identify a marked decline in dinosaur genus richness during the closing stages of the Cretaceous Period, indicating that the clade decreased in diversity for several million years prior to the final extinction of non-avian dinosaurs at the Cretaceous-Palaeocene boundary. PMID:19403535

  15. Dinosaur diversity and the rock record

    PubMed Central

    Barrett, Paul M.; McGowan, Alistair J.; Page, Victoria

    2009-01-01

    Palaeobiodiversity analysis underpins macroevolutionary investigations, allowing identification of mass extinctions and adaptive radiations. However, recent large-scale studies on marine invertebrates indicate that geological factors play a central role in moulding the shape of diversity curves and imply that many features of such curves represent sampling artefacts, rather than genuine evolutionary events. In order to test whether similar biases affect diversity estimates for terrestrial taxa, we compiled genus-richness estimates for three Mesozoic dinosaur clades (Ornithischia, Sauropodomorpha and Theropoda). Linear models of expected genus richness were constructed for each clade, using the number of dinosaur-bearing formations available through time as a proxy for the amount of fossiliferous rock outcrop. Modelled diversity estimates were then compared with observed patterns. Strong statistically robust correlations demonstrate that almost all aspects of ornithischian and theropod diversity curves can be explained by geological megabiases, whereas the sauropodomorph record diverges from modelled predictions and may be a stronger contender for identifying evolutionary signals. In contrast to other recent studies, we identify a marked decline in dinosaur genus richness during the closing stages of the Cretaceous Period, indicating that the clade decreased in diversity for several million years prior to the final extinction of non-avian dinosaurs at the Cretaceous–Palaeocene boundary. PMID:19403535

  16. "No. 190. Grand Valley Diversion Dam. Diversion gates, water flowing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    "No. 190. Grand Valley Diversion Dam. Diversion gates, water flowing into high line. June, 1917. R.B.D." - Grand Valley Diversion Dam, Half a mile north of intersection of I-70 & Colorado State Route 65, Cameo, Mesa County, CO

  17. 2. Salmon Creek Diversion Dam, overview, diversion weir center foreground, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Salmon Creek Diversion Dam, overview, diversion weir center foreground, headworks overflow weir to center left, view to east - Salmon Creek Diversion Dam, Salmon Creek, Okanogan, Okanogan County, WA

  18. Embracing "Soft Skill" Diversity in the Workplace (Invited)

    NASA Astrophysics Data System (ADS)

    Thomas, T.

    2010-12-01

    Embracing "Soft Skill" Diversity in the Workplace Terri Thomas, Sr. Director Global Customer Support ShoreTel INRODUCTION Truly successful diversity programs go beyond gender, age, ethnicity, race, sexual orientation and spiritual practice. They include diversity of thought, style, leadership and communication styles, the so called “soft skills”. The increasing need for global workforces is stronger than ever and high performance teams have fully embraced, successfully harnessed and put into practice robust diversity programs than include a “soft skill” focus. Managing diversity presents significant organizational challenges, and is not an easy task, particularly in organizations that are heavily weighted with highly technical professionals such as engineers, accountants etc.. The focus of this presentation is on leveraging the “Soft Skills” diversity in technical work environments to create high performance and highly productive teams. WHY DIVERSITY and WHY NOW? Due to increasing changes in the U.S. population, in order to stay competitive, companies need to focus on diversity and look for ways to become inclusive organizations because diversity has the potential of yielding greater productivity and competitive advantages . Managing and valuing diversity is a key component of effective people management, which can improve workplace productivity (Black Enterprise, 2001). Changing demographics, from organizational restructuring, women in the workplace, equal opportunity legislation and other legal issues, are forcing organizations to become more aggressive in implementing robust diversity practices. However, YOU do not need to wait for your organization to introduce a formal “Diversity” program. There are steps you can take to introduce diversity into your own workgroups. There is no “one single answer” to solve this issue, however this discussion will provide thought provoking ideas, examples of success and failure and a starting point for you to implement “soft skill” diversity practices in your work environment. Most workplaces are made up of many aspects of diversity already so why not embrace it and use it to your competitive advantage.

  19. [Ethical aspects of forensic psychiatry].

    PubMed

    Muysers, Jutta

    2014-07-01

    Ethical aspects of forensic psychiatry disclose a tension between complementary and conflicting issues. The field of tension extends from offenders and their criminal offence to experts, therapists and conditions of inpatient treatment. In addition, there are legal and political aspects as well as aspects concerning the public, the victims and their next of kins and finally the media. PMID:24983577

  20. A Five-miRNA Panel Identified From a Multicentric Casecontrol Study Serves as a Novel Diagnostic Tool for Ethnically Diverse Non-small-cell Lung Cancer Patients

    PubMed Central

    Wang, Cheng; Ding, Meng; Xia, Mingde; Chen, Sidi; Van Le, Anh; Soto-Gil, Rafael; Shen, Yi; Wang, Nan; Wang, Junjun; Gu, Wanjian; Wang, Xiangdong; Zhang, Yanni; Zen, Ke; Chen, Xi; Zhang, Chunni; Zhang, Chen-Yu

    2015-01-01

    Circulating microRNAs (miRNAs) are promising biomarkers for cancer detection. However, multiethnic and multicentric studies of non-small-cell lung cancer (NSCLC) are lacking. We recruited 221 NSCLC patients, 161 controls and 56 benign nodules from both China and America. Initial miRNA screening was performed using the TaqMan Low Density Array followed by confirming individually by RT-qPCR in Chinese cohorts. Finally, we performed a blind trial from an American cohort to validate our findings. RT-qPCR confirmed that miR-483-5p, miR-193a-3p, miR-25, miR-214 and miR-7 were significantly elevated in patients compared to controls. The areas under the curve (AUCs) of the ROC curve of this five-serum miRNA panel were 0.976 (95% CI, 0.9391.0; P<0.0001) and 0.823 (95% CI, 0.750.896; P<0.0001) for the two confirmation sets, respectively. In the blind trial, the panel correctly classified 95% NSCLC cases and 84% controls from the American cohort. Most importantly, the panel was capable of distinguishing NSCLC from benign nodules with an AUC of 0.979 (95% CI, 0.9591.0) in the American cohort and allowed correct prediction of 86% and 95% stage III tumors in the Chinese and American cohorts, respectively. This serum miRNA panel holds the potential for diagnosing ethnically diverse NSCLC patients. PMID:26629532

  1. Geometrical aspects of entanglement

    SciTech Connect

    Leinaas, Jon Magne; Myrheim, Jan; Ovrum, Eirik

    2006-07-15

    We study geometrical aspects of entanglement, with the Hilbert-Schmidt norm defining the metric on the set of density matrices. We focus first on the simplest case of two two-level systems and show that a 'relativistic' formulation leads to a complete analysis of the question of separability. Our approach is based on Schmidt decomposition of density matrices for a composite system and nonunitary transformations to a standard form. The positivity of the density matrices is crucial for the method to work. A similar approach works to some extent in higher dimensions, but is a less powerful tool. We further present a numerical method for examining separability and illustrate the method by a numerical study of bound entanglement in a composite system of two three-level systems.

  2. Historical aspects of anxiety

    PubMed Central

    Klein, Donald F.

    2002-01-01

    Anxiety is a key term for behavioral, psychoanalytic, neuroendocrine, and psychopharmacological observations and theories. Commenting on its historical aspects is difficult, since history is properly a study of primary data. Unfortunately, much clinical anecdote does not correspond to factual records of a long time ago. Even reports of objective studies may suffer from allegiance effects. This essay therefore primarily reflects the personal impact of others' work against the background of my experiences, clinical and scientific. These lead me to question the assumption that anxiety, as it exists in syndromal disturbances, is simply the quantitative extreme of the normal anxiety that occurs during the anticipation of danger. An alternative view that emphasizes dysfunctions of distinct evolved adaptive alarm systems is presented. PMID:22033777

  3. Aspects of Plant Intelligence

    PubMed Central

    TREWAVAS, ANTHONY

    2003-01-01

    Intelligence is not a term commonly used when plants are discussed. However, I believe that this is an omission based not on a true assessment of the ability of plants to compute complex aspects of their environment, but solely a reflection of a sessile lifestyle. This article, which is admittedly controversial, attempts to raise many issues that surround this area. To commence use of the term intelligence with regard to plant behaviour will lead to a better understanding of the complexity of plant signal transduction and the discrimination and sensitivity with which plants construct images of their environment, and raises critical questions concerning how plants compute responses at the whole‐plant level. Approaches to investigating learning and memory in plants will also be considered. PMID:12740212

  4. Toxicological aspects of fire.

    PubMed

    Stefanidou, M; Athanaselis, S

    2004-08-01

    Most fatalities from fires are not due to burns, but are a result of inhalation of toxic gases produced during combustion. Fire produces a complex toxic environment, involving flame, heat, oxygen depletion, smoke and toxic gases. As a wide variety of synthetic materials is used in buildings (insulation, furniture, carpeting, electric wiring covering, decorative items), the potential for poisoning from inhalation of products of combustion is continuously increasing. In the present review, the problems that are present in a fire event, the toxicology of the toxic substances and the specific chemical hazards to firefighters are described. Regulatory toxicology aspects are presented concerning the use of non-flammable building and furnishing materials to prevent fires and decrease of poisonings and deaths resulting from fires. PMID:15303394

  5. Laboratory aspects of bioterrorism-related anthrax--from identification to molecular subtyping to microbial forensics.

    PubMed

    Popović, Tanja; Glass, Mindy

    2003-06-01

    During the bioterrorism-associated anthrax investigation of 2001 in the United States, 11 patients were diagnosed with inhalational anthrax and 11 more with the cutaneous forms of the disease. Over 125,000 specimens were processed at laboratories of the Laboratory Response Network including those at the Centers for Disease Control and Prevention. Although the 2001 anthrax investigation initially began as a public health investigation, the forensic aspect quickly became a preeminent component of the investigation. Whereas a public health investigation aims primarily to identify the causative agent and its source, so that appropriate and timely control and preventative measures can be implemented, a forensic investigation goes further to associate the source of the causative agent with a specific individual or group. In addition to identification and molecular characterization of the causative agents, which are the crucial components of forensic microbiology, there are many other requirements and activities that need to be in place for investigators to successfully complete a forensic investigation. These activities include establishment of quality assurance/quality control criteria and regular proficiency testing for all laboratories where evidence is analyzed; additional and/or specialized training in handling and processing samples in accordance with forensic microbiology criteria, not only for first responders but also for laboratory and other public health scientists; and establishing and maintaining repositories and databases containing isolates of diverse temporal and geographic origins to provide a comparative and diverse background for investigators to identify and track the origin and source of such agents. PMID:12808729

  6. The Uniformity and Diversity of Language: Evidence from Sign Language

    PubMed Central

    Sandler, Wendy

    2010-01-01

    Evidence from sign language strongly supports three positions: (1) language is a coherent system with universal properties; (2) sign languages diverge from spoken languages in some aspects of their structure; and (3) domain-external factors can be identified that account for some crucial aspects of language structure -- uniform and diverse -- in both modalities. Assuming that any of these positions excludes the others defeats the purpose of the enterprise. PMID:21076645

  7. Diverse Bacterial Microcompartment Organelles

    PubMed Central

    Chowdhury, Chiranjit; Sinha, Sharmistha; Chun, Sunny; Yeates, Todd O.

    2014-01-01

    SUMMARY Bacterial microcompartments (MCPs) are sophisticated protein-based organelles used to optimize metabolic pathways. They consist of metabolic enzymes encapsulated within a protein shell, which creates an ideal environment for catalysis and facilitates the channeling of toxic/volatile intermediates to downstream enzymes. The metabolic processes that require MCPs are diverse and widely distributed and play important roles in global carbon fixation and bacterial pathogenesis. The protein shells of MCPs are thought to selectively control the movement of enzyme cofactors, substrates, and products (including toxic or volatile intermediates) between the MCP interior and the cytoplasm of the cell using both passive electrostatic/steric and dynamic gated mechanisms. Evidence suggests that specialized shell proteins conduct electrons between the cytoplasm and the lumen of the MCP and/or help rebuild damaged iron-sulfur centers in the encapsulated enzymes. The MCP shell is elaborated through a family of small proteins whose structural core is known as a bacterial microcompartment (BMC) domain. BMC domain proteins oligomerize into flat, hexagonally shaped tiles, which assemble into extended protein sheets that form the facets of the shell. Shape complementarity along the edges allows different types of BMC domain proteins to form mixed sheets, while sequence variation provides functional diversification. Recent studies have also revealed targeting sequences that mediate protein encapsulation within MCPs, scaffolding proteins that organize lumen enzymes and the use of private cofactor pools (NAD/H and coenzyme A [HS-CoA]) to facilitate cofactor homeostasis. Although much remains to be learned, our growing understanding of MCPs is providing a basis for bioengineering of protein-based containers for the production of chemicals/pharmaceuticals and for use as molecular delivery vehicles. PMID:25184561

  8. Differential changes in self-reported aspects of interoceptive awareness through 3 months of contemplative training

    PubMed Central

    Bornemann, Boris; Herbert, Beate M.; Mehling, Wolf E.; Singer, Tania

    2015-01-01

    Interoceptive body awareness (IA) is crucial for psychological well-being and plays an important role in many contemplative traditions. However, until recently, standardized self-report measures of IA were scarce, not comprehensive, and the effects of interoceptive training on such measures were largely unknown. The Multidimensional Assessment of Interoceptive Awareness (MAIA) questionnaire measures IA with eight different scales. In the current study, we investigated whether and how these different aspects of IA are influenced by a 3-months contemplative intervention in the context of the ReSource project, in which 148 subjects engaged in daily practices of “Body Scan” and “Breath Meditation.” We developed a German version of the MAIA and tested it in a large and diverse sample (n = 1,076). Internal consistencies were similar to the English version (0.56–0.89), retest reliability was high (rs: 0.66–0.79), and the MAIA showed good convergent and discriminant validity. Importantly, interoceptive training improved five out of eight aspects of IA, compared to a retest control group. Participants with low IA scores at baseline showed the biggest changes. Whereas practice duration only weakly predicted individual differences in change, self-reported liking of the practices and degree of integration into daily life predicted changes on most scales. Interestingly, the magnitude of observed changes varied across scales. The strongest changes were observed for the regulatory aspects of IA, that is, how the body is used for self-regulation in daily life. No significant changes were observed for the Noticing aspect (becoming aware of bodily changes), which is the aspect that is predominantly assessed in other IA measures. This differential pattern underscores the importance to assess IA multi-dimensionally, particularly when interested in enhancement of IA through contemplative practice or other mind–body interventions. PMID:25610410

  9. Managing biological diversity

    USGS Publications Warehouse

    Samson, Fred B.; Knopf, Fritz L.

    1993-01-01

    Biological diversity is the variety of life and accompanying ecological processes (Off. Technol. Assess. 1987, Wilcove and Samson 1987, Keystone 1991). Conservation of biological diversity is a major environmental issue (Wilson 1988, Counc. Environ. Quality 1991). The health and future of the earth's ecological systems (Lubchenco et al. 1991), global climate change (Botkin 1990), and an ever-increasing rate in loss of species, communities, and ecological systems (Myers 1990) are among issues drawing biological diversity to the mainstream of conservation worldwide (Int. Union Conserv. Nat. and Nat. Resour. [IUCN] et al. 1991). The legal mandate for conserving biological diversity is now in place (Carlson 1988, Doremus 1991). More than 19 federal laws govern the use of biological resources in the United States (Rein 1991). The proposed National Biological Diversity Conservation and Environmental Research Act (H.R. 585 and S.58) notes the need for a national biological diversity policy, would create a national center for biological diversity research, and recommends a federal interagency strategy for ecosystem conservation. There are, however, hard choices ahead for the conservation of biological diversity, and biologists are grappling with how to set priorities in research and management (Roberts 1988). We sense disillusion among field biologists and managers relative to how to operationally approach the seemingly overwhelming charge of conserving biological diversity. Biologists also need to respond to critics like Hunt (1991) who suggest a tree farm has more biological diversity than an equal area of old-growth forest. At present, science has played only a minor role in the conservation of biological diversity (Weston 1992) with no unified approach available to evaluate strategies and programs that address the quality and quantity of biological diversity (Murphy 1990, Erwin 1992). Although actions to conserve biological diversity need to be clearly defined by viewing issues across biological, spatial, and temporal scales (Knopf and Smith 1992), natural resource managers find much conflicting information in the literature on strategies and programs for the conservation of biological diversity (Ehrlich 1992). Moreover, recommendations provided in much of the published information available for planning or decisions not only can be debated but may prove counterproductive if implemented. Current operational efforts beg for clearer focus on fundamental concepts central to daily decisions that impact native biological diversity. Recognizing that many biologists would provide different council and at the risk of oversimplification, we offer the following 4 topical issues as fundamental guidance to wise conservation action. These recommendations are based on our collective experiences working within conservation agencies since our original, collaborative essay (Samson and Knopf 1982). They are offered as initial, rather than authoritative, steps to better align research and management decisions with what we perceive as the critical issues in conserving biological diversity at the landscape and ecosystem levels of resolution.

  10. Multimedia and Cultural Diversity.

    ERIC Educational Resources Information Center

    Pacino, Maria A.; Pacino, Joe L.

    1996-01-01

    Describes development of a multimedia courseware package available on videodisc and CD-ROM for use in teaching cultural awareness and diversity. This interactive package uses role-playing questions and answers and discussion. (JKP)

  11. How to Make Diversity Pay.

    ERIC Educational Resources Information Center

    Rice, Faye

    1994-01-01

    Companies that manage diversity successfully have common characteristics: chief executives' commitment, diversity as a business objective, fair compensation and career tracking, careful diversity training, consistent focus during downsizing, and plans that address the concerns of white males. (SK)

  12. GCS plan for software aspects of certification

    NASA Technical Reports Server (NTRS)

    Shagnea, Anita M.; Lowman, Douglas S.; Withers, B. Edward

    1990-01-01

    As part of the Guidance and Control Software (GCS) research project being sponsored by NASA to evaluate the failure processes of software, standard industry software development procedures are being employed. To ensure that these procedures are authentic, the guidelines outlined in the Radio Technical Commission for Aeronautics (RTCA/DO-178A document entitled, software considerations in airborne systems and equipment certification, were adopted. A major aspect of these guidelines is proper documentation. As such, this report, the plan for software aspects of certification, was produced in accordance with DO-178A. An overview is given of the GCS research project, including the goals of the project, project organization, and project schedules. It also specifies the plans for all aspects of the project which relate to the certification of the GCS implementations developed under a NASA contract. These plans include decisions made regarding the software specification, accuracy requirements, configuration management, implementation development and verification, and the development of the GCS simulator.

  13. Aspects of two corrosion processes relevant to military hardware

    SciTech Connect

    Braithwaite, J.W.; Buchheit, R.G.

    1997-11-01

    Corrosion is a leading material degradation mode observed in many military systems. This report contains a description of a small project that was performed to allow some of the important electrochemical aspects of two distinct and potentially relevant degradation modes to be better understood: environmentally assisted cracking (EAC) of aluminum alloys and corrosion in moist salt. Two specific and respective tasks were completed: (A) the characterization of the effect of aluminum microstructural variability on its susceptibility to EAC, and (B) the development of experimental and analytical techniques that can be used to identify the factors and processes that influence the corrosivity of moist salt mixtures. The resultant information constitutes part of the basis needed to ultimately predict component reliability and/or possibly to identify techniques that could be used to control corrosion in critical components. In Task A, a physical model and related understanding for the relevant degradation processes were formulated. The primary result from Task B included the identification and qualitative validation of a methodology for determining the corrosivity of salt mixtures. A detailed compilation of the results obtained from each of these two diverse tasks is presented separately in the body of this report.

  14. Diversity history of Cenozoic marine siliceous plankton

    NASA Astrophysics Data System (ADS)

    Lazarus, David; Renaudie, Johan

    2014-05-01

    Marine planktonic diatoms and polycystine radiolarians, both with shells of opaline silica, make up a large part of the deep-sea sediment fossil record. Diatom export of organic material to the deep ocean and sediments strongly affects the global carbon cycle; while both groups compete for, and are regulated by the availability of, dissolved silica derived from global weathering. Diatoms and radiolarians also both have a relatively (compared to foraminifera or coccolithophores) complex biogeography, with diverse, endemic polar and tropical assemblages. Changes in past diatom and radiolarian diversity can be used to understand how the ocean's biologic pump has evolved, how co-evolution between groups occurs, and how nutrient availability controls evolutionary change. Lazarus et al. (2014) recently showed that diatom diversity increased by a factor of ca 3.5X over the Cenozoic, with a temporary peak in the latest Eocene, a late Oligocene-early Miocene low interval, very strong diversification in the late Miocene-early Pliocene, and minor decline in the late Pliocene-Recent. Only Phanerozoic scale radiolarian diversity estimates have been available until now, and these are strongly biased by sample size. We employed similar data (NSB database) and methods (1 my bins, 'sqs' subsampling, outlier removal using Pacman trims) as Lazarus et al. (2014) to calculate, for the first time, a detailed estimate of radiolarian diversity history, and origination and extinction rates over the last 50 my, the period for which sufficient NSB data is available. Radiolarian diversity increases almost monotonically by a factor of 5, with relatively rapid increases in the mid Eocene (high relative origination) and early Miocene (due to low extinction rates), and a moderate decline in the Plio-Pleistocene due to high extinction rates. Combined high rates of both extinction and origination, with little diversity change, are seen at the Eocene-Oligocene boundary. Most of these events can be related to changing global paleoceanographic conditions. Radiolarians show a major decrease in Cenozoic silica usage, apparently due to the rise of diatoms and consequent reduction of surface water silica concentrations (Lazarus et al. 2009). This inference based on diatom diversity has been confirmed (Renaudie et al., this meeting) with new estimates showing Cenozoic increasing rates of global diatom silica deposition. Our new radiolarian results show this did not negatively impact radiolarian diversity. Presumably increasing diversity from increasing faunal provinciality dominated Cenozoic radiolarian diversity dynamics, similar to the diversity controls on diatoms (Lazarus et al. 2014). Lazarus et al. (2009). PNAS 106:9333-9338. Lazarus et al. (2014). PLOS One (in press).

  15. Diversity, Pathogenicity And Control of Verticillium Species.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genus Verticillium is a cosmopolitan group of ascomycetous fungi, encompassing phytopathogenic species that cause vascular wilts of plants. Two of these species, V. dahliae and V. albo-atrum, cause billions of dollars in annual crop losses worldwide. The soil habitat of these species, the exte...

  16. The biological origin of linguistic diversity.

    PubMed

    Baronchelli, Andrea; Chater, Nick; Pastor-Satorras, Romualdo; Christiansen, Morten H

    2012-01-01

    In contrast with animal communication systems, diversity is characteristic of almost every aspect of human language. Languages variously employ tones, clicks, or manual signs to signal differences in meaning; some languages lack the noun-verb distinction (e.g., Straits Salish), whereas others have a proliferation of fine-grained syntactic categories (e.g., Tzeltal); and some languages do without morphology (e.g., Mandarin), while others pack a whole sentence into a single word (e.g., Cayuga). A challenge for evolutionary biology is to reconcile the diversity of languages with the high degree of biological uniformity of their speakers. Here, we model processes of language change and geographical dispersion and find a consistent pressure for flexible learning, irrespective of the language being spoken. This pressure arises because flexible learners can best cope with the observed high rates of linguistic change associated with divergent cultural evolution following human migration. Thus, rather than genetic adaptations for specific aspects of language, such as recursion, the coevolution of genes and fast-changing linguistic structure provides the biological basis for linguistic diversity. Only biological adaptations for flexible learning combined with cultural evolution can explain how each child has the potential to learn any human language. PMID:23118922

  17. Clinical aspects of dermatoglyphics.

    PubMed

    Schaumann, B A; Opitz, J M

    1991-01-01

    As demonstrated above, considerable progress has been made in the understanding of the associations between dermatoglyphics and various medical disorders, as a result of which dermatoglyphic analysis has been established as a useful diagnostic and research tool in medicine, providing important insights into the inheritance and embryologic development of many studied clinical disorders. Many unanswered questions and misconceptions still remain, though. Further well-designed investigations, avoiding the pitfalls of many earlier studies, will be needed to reevaluate some of the existing claims and to determine the real value of dermatoglyphics in medicine. The benefits of a dermatoglyphic examination in individual patients in clinical genetic practice are clear; a more widespread application of this tool by clinical geneticists and pediatricians should be encouraged. Embryologic and experimental dermatoglyphic studies clearly hold a considerable potential for a better understanding of the factors influencing the development of the epidermal ridge patterns. Utilized together with newly developed methods and insights gained in recent studies of other aspects of dermatoglyphics, they should significantly advance the studies of the relationship between dermatoglyphic variation and medical disorders. PMID:1786352

  18. Psychosocial aspects of abortion

    PubMed Central

    Illsley, Raymond; Hall, Marion H.

    1976-01-01

    The literature on psychosocial aspects of abortion is confusing. Individual publications must be interpreted in the context of cultural, religious, and legal constraints obtaining in a particular society at a given time, with due attention to the status and availability of alternatives to abortion that might be chosen by a woman with an “unwanted” pregnancy. A review of the literature shows that, where careful pre- and post-abortion assessments are made, the evidence is that psychological benefit commonly results, and serious adverse emotional sequelae are rare. The outcome of refused abortion seems less satisfactory, with regrets and distress frequently occurring. Research on the administration of abortion services suggests that counselling is often of value, that distress is frequently caused by delays in deciding upon and in carrying out abortions, and by unsympathetic attitudes of service providers. The phenomenon of repeated abortion seeking should be seen in the context of the availability and cost of contraception and sterilization. The place of sterilization with abortion requires careful study. A recommendation is made for observational descriptive research on populations of women with potentially unwanted pregnancies in different cultures, with comparisons of management systems and an evaluation of their impact on service users. PMID:1085671

  19. Aspects of quantum cosmology.

    NASA Astrophysics Data System (ADS)

    Page, D. N.

    Quantum mechanics may be formulated as Sensible Quantum Mechanics (SQM) so that it contains nothing probabilistic, except, in a certain frequency sense, conscious perceptions. Sets of these perceptions can be deterministically realized with measures given by expectation values of positive-operator-valued awareness operators in a quantum state of the universe which never jumps or collapses. Ratios of the measures for these sets of perceptions can be interpreted as frequency-type probabilities for many actually existing sets rather than as propensities for potentialities to be actualized, so there is nothing indeterministic in SQM. These frequency-type probabilities generally cannot be given by the ordinary quantum "probabilities" for a single set of alternatives. Probabilism, or ascribing probabilities to unconscious aspects of the world, may be seen to be an aethemamorphic myth. No fundamental correlation or equivalence is postulated between different perceptions, so SQM, a variant of Everett's "many-worlds" framework, is a "many-perceptions" framework but not a "many-minds" framework. Different detailed SQM theories may be tested against experienced perceptions by the typicalities (defined herein) they predict for these perceptions. One may adopt the Conditional Aesthemic Principle: among the set of all conscious perceptions, our perceptions are likely to be typical.

  20. Strategic Aspects of Communication

    NASA Astrophysics Data System (ADS)

    Hagen, Edward; Hammerstein, Peter; Hess, Nicole

    Rarely do human behavioral scientists and scholars study language, music, and other forms of communication as strategies—a means to some end. Some even deny that communication is the primary function of these phenomena. Here we draw upon selections of our earlier work to briefly define the strategy concept and sketch how decision theory, developed to explain the behavior of rational actors, is applied to evolved agents. Communication can then be interpreted as a strategy that advances the "fitness interests" of such agents. When this perspective is applied to agents with conflicts of interest, deception emerges as an important aspect of communication. We briefly review costly signaling, one solution to the problem of honest communication among agents with conflicts of interest. We also explore the subversion of cooperative signals by parasites and by plants defending themselves against herbivores, and we touch on biases in human gossip. Experiments with artificial embodied and communicating agents confirm that when there are conflicts of interest among agents, deception readily evolves. Finally, we consider signaling among super-organisms and the possible implications for understanding human music and language.