USSR and Eastern Europe Scientific Abstracts, Cybernetics, Computers and Automation Technology, Number 35

DTIC Science & Technology

1978-09-12

the population. Only a socialist, planned economy can cope with such problems. However, the in- creasing complexity of the tasks faced’ by...the development of systems allowing man-machine dialogue does not decrease, but rather increase the complexity of the systems involved, simply...shifting the complexity to another sphere, where it is invisible to the human utilizing the system. Figures 5; refer- ences 3: 2 Russian, 1 Western

Effector peptides of the renin-angiotensin system in the central mechanisms of acquired and innate behavior in thirst in rats.

PubMed

Vlasenko, R Ya; Kotov, A V

2007-03-01

We report here a comparative analysis of the involvement of a number of components of the renin-angiotensin system in the performance of simple and complex forms of drinking behavior and thirst-associated non-drinking types of behavior. On central (intracerebroventricular) microinjection, [des-Asp1]-angiotensin I at doses equieffective to those of angiotensins II and III was found to be involved only in the performance of simple (taking water from the bowl) and linked forms of activity (comfort behavior, stress grooming, orientational-investigative, and feeding behavior). Angiotensin II was involved in the central mechanisms of complex acquired drinking behavior, selectively modulating its key stages (initial, final), while angiotensin III was involved only in the mechanisms of reproduction of the complex skill. All three substances induced "innate patterns of behavior" specific for each compound, these occurring at fixed periods of time after intracerebral microinjection. The effects of these substances were selectively suppressed by the AT1 receptor blocker losartan potassium.

48 CFR 319.705-5 - Awards involving subcontracting plans.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Awards involving subcontracting plans. 319.705-5 Section 319.705-5 Federal Acquisition Regulations System HEALTH AND HUMAN... contract award package, depending upon the circumstances and complexity of the individual acquisition. ...

48 CFR 319.705-5 - Awards involving subcontracting plans.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Awards involving subcontracting plans. 319.705-5 Section 319.705-5 Federal Acquisition Regulations System HEALTH AND HUMAN... contract award package, depending upon the circumstances and complexity of the individual acquisition. ...

Supporting Space Systems Design via Systems Dependency Analysis Methodology

NASA Astrophysics Data System (ADS)

Guariniello, Cesare

The increasing size and complexity of space systems and space missions pose severe challenges to space systems engineers. When complex systems and Systems-of-Systems are involved, the behavior of the whole entity is not only due to that of the individual systems involved but also to the interactions and dependencies between the systems. Dependencies can be varied and complex, and designers usually do not perform analysis of the impact of dependencies at the level of complex systems, or this analysis involves excessive computational cost, or occurs at a later stage of the design process, after designers have already set detailed requirements, following a bottom-up approach. While classical systems engineering attempts to integrate the perspectives involved across the variety of engineering disciplines and the objectives of multiple stakeholders, there is still a need for more effective tools and methods capable to identify, analyze and quantify properties of the complex system as a whole and to model explicitly the effect of some of the features that characterize complex systems. This research describes the development and usage of Systems Operational Dependency Analysis and Systems Developmental Dependency Analysis, two methods based on parametric models of the behavior of complex systems, one in the operational domain and one in the developmental domain. The parameters of the developed models have intuitive meaning, are usable with subjective and quantitative data alike, and give direct insight into the causes of observed, and possibly emergent, behavior. The approach proposed in this dissertation combines models of one-to-one dependencies among systems and between systems and capabilities, to analyze and evaluate the impact of failures or delays on the outcome of the whole complex system. The analysis accounts for cascading effects, partial operational failures, multiple failures or delays, and partial developmental dependencies. The user of these methods can assess the behavior of each system based on its internal status and on the topology of its dependencies on systems connected to it. Designers and decision makers can therefore quickly analyze and explore the behavior of complex systems and evaluate different architectures under various working conditions. The methods support educated decision making both in the design and in the update process of systems architecture, reducing the need to execute extensive simulations. In particular, in the phase of concept generation and selection, the information given by the methods can be used to identify promising architectures to be further tested and improved, while discarding architectures that do not show the required level of global features. The methods, when used in conjunction with appropriate metrics, also allow for improved reliability and risk analysis, as well as for automatic scheduling and re-scheduling based on the features of the dependencies and on the accepted level of risk. This dissertation illustrates the use of the two methods in sample aerospace applications, both in the operational and in the developmental domain. The applications show how to use the developed methodology to evaluate the impact of failures, assess the criticality of systems, quantify metrics of interest, quantify the impact of delays, support informed decision making when scheduling the development of systems and evaluate the achievement of partial capabilities. A larger, well-framed case study illustrates how the Systems Operational Dependency Analysis method and the Systems Developmental Dependency Analysis method can support analysis and decision making, at the mid and high level, in the design process of architectures for the exploration of Mars. The case study also shows how the methods do not replace the classical systems engineering methodologies, but support and improve them.

Groundwater Site Characterization: A Systems Perspective.

ERIC Educational Resources Information Center

Wolf, Frederick

1994-01-01

Groundwater remedial actions are highly complex projects. During the past 10 years, many remedial actions have begun, but very few have been successfully completed. This paper describes the complexity of groundwater remediation and offers an alternative management approach involving systems movement successfully utilized at a site in the…

Technology-Supported Learning Innovation in Cultural Contexts

ERIC Educational Resources Information Center

Zhang, Jianwei

2010-01-01

Many reform initiatives adopt a reductionist, proceduralized approach to cultural change, assuming that deep changes can be realized by introducing new classroom activities, textbooks, and technological tools. This article elaborates a complex system perspective of learning culture: A learning culture as a complex system involves macro-level…

Methods Used to Support a Life Cycle of Complex Engineering Products

NASA Astrophysics Data System (ADS)

Zakharova, Alexandra A.; Kolegova, Olga A.; Nekrasova, Maria E.; Eremenko, Andrey O.

2016-08-01

Management of companies involved in the design, development and operation of complex engineering products recognize the relevance of creating systems for product lifecycle management. A system of methods is proposed to support life cycles of complex engineering products, based on fuzzy set theory and hierarchical analysis. The system of methods serves to demonstrate the grounds for making strategic decisions in an environment of uncertainty, allows the use of expert knowledge, and provides interconnection of decisions at all phases of strategic management and all stages of a complex engineering product lifecycle.

Student Learning of Complex Earth Systems: A Model to Guide Development of Student Expertise in Problem-Solving

ERIC Educational Resources Information Center

Holder, Lauren N.; Scherer, Hannah H.; Herbert, Bruce E.

2017-01-01

Engaging students in problem-solving concerning environmental issues in near-surface complex Earth systems involves developing student conceptualization of the Earth as a system and applying that scientific knowledge to the problems using practices that model those used by professionals. In this article, we review geoscience education research…

The Hsp90 chaperone complex regulates GDI-dependent Rab recycling.

PubMed

Chen, Christine Y; Balch, William E

2006-08-01

Rab GTPase regulated hubs provide a framework for an integrated coding system, the membrome network, that controls the dynamics of the specialized exocytic and endocytic membrane architectures found in eukaryotic cells. Herein, we report that Rab recycling in the early exocytic pathways involves the heat-shock protein (Hsp)90 chaperone system. We find that Hsp90 forms a complex with guanine nucleotide dissociation inhibitor (GDI) to direct recycling of the client substrate Rab1 required for endoplasmic reticulum (ER)-to-Golgi transport. ER-to-Golgi traffic is inhibited by the Hsp90-specific inhibitors geldanamycin (GA), 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG), and radicicol. Hsp90 activity is required to form a functional GDI complex to retrieve Rab1 from the membrane. Moreover, we find that Hsp90 is essential for Rab1-dependent Golgi assembly. The observation that the highly divergent Rab GTPases Rab1 involved in ER-to-Golgi transport and Rab3A involved in synaptic vesicle fusion require Hsp90 for retrieval from membranes lead us to now propose that the Hsp90 chaperone system may function as a general regulator for Rab GTPase recycling in exocytic and endocytic trafficking pathways involved in cell signaling and proliferation.

Critical issues in NASA information systems

NASA Technical Reports Server (NTRS)

1987-01-01

The National Aeronautics and Space Administration has developed a globally-distributed complex of earth resources data bases since LANDSAT 1 was launched in 1972. NASA envisages considerable growth in the number, extent, and complexity of such data bases, due to the improvements expected in its remote sensing data rates, and the increasingly multidisciplinary nature of its scientific investigations. Work already has begun on information systems to support multidisciplinary research activities based on data acquired by the space station complex and other space-based and terrestrial sources. In response to a request from NASA's former Associate Administrator for Space Science and Applications, the National Research Council convened a committee in June 1985 to identify the critical issues involving information systems support to space science and applications. The committee has suggested that OSSA address four major information systems issues; centralization of management functions, interoperability of user involvement in the planning and implementation of its programs, and technology.

CALFED--An experiment in science and decisionmaking

USGS Publications Warehouse

Taylor, Kimberly A.; Jacobs, Katharine L.; Luoma, Samuel N.

2003-01-01

The CALFED Bay-Delta Program faces a challenging assignment: to develop a collaborative state-federal management plan for the complex river system and involve multiple stakeholders (primarily municipal, agricultural, and environmental entities) whose interests frequently are in direct conflict. Although many resource-management issues involve multiple stakeholders and conflict is integral to their discussion, the CALFED experience is unique because of its shared state and federal roles, the magnitude and significance of stakeholder participation, and the complexity of the scientific issues involved.

Are attractors 'strange', or is life more complicated than the simple laws of physics?

PubMed

Pogun, S

2001-01-01

Interesting and intriguing questions involve complex systems whose properties cannot be explained fully by reductionist approaches. Last century was dominated by physics, and applying the simple laws of physics to biology appeared to be a practical solution to understand living organisms. However, although some attributes of living organisms involve physico-chemical properties, the genetic program and evolutionary history of complex biological systems make them unique and unpredictable. Furthermore, there are and will be 'unobservable' phenomena in biology which have to be accounted for.

Simulation of Propellant Loading System Senior Design Implement in Computer Algorithm

NASA Technical Reports Server (NTRS)

Bandyopadhyay, Alak

2010-01-01

Propellant loading from the Storage Tank to the External Tank is one of the very important and time consuming pre-launch ground operations for the launch vehicle. The propellant loading system is a complex integrated system involving many physical components such as the storage tank filled with cryogenic fluid at a very low temperature, the long pipe line connecting the storage tank with the external tank, the external tank along with the flare stack, and vent systems for releasing the excess fuel. Some of the very important parameters useful for design purpose are the prediction of pre-chill time, loading time, amount of fuel lost, the maximum pressure rise etc. The physics involved for mathematical modeling is quite complex due to the fact the process is unsteady, there is phase change as some of the fuel changes from liquid to gas state, then conjugate heat transfer in the pipe walls as well as between solid-to-fluid region. The simulation is very tedious and time consuming too. So overall, this is a complex system and the objective of the work is student's involvement and work in the parametric study and optimization of numerical modeling towards the design of such system. The students have to first become familiar and understand the physical process, the related mathematics and the numerical algorithm. The work involves exploring (i) improved algorithm to make the transient simulation computationally effective (reduced CPU time) and (ii) Parametric study to evaluate design parameters by changing the operational conditions

Informational analysis involving application of complex information system

NASA Astrophysics Data System (ADS)

Ciupak, Clébia; Vanti, Adolfo Alberto; Balloni, Antonio José; Espin, Rafael

The aim of the present research is performing an informal analysis for internal audit involving the application of complex information system based on fuzzy logic. The same has been applied in internal audit involving the integration of the accounting field into the information systems field. The technological advancements can provide improvements to the work performed by the internal audit. Thus we aim to find, in the complex information systems, priorities for the work of internal audit of a high importance Private Institution of Higher Education. The applied method is quali-quantitative, as from the definition of strategic linguistic variables it was possible to transform them into quantitative with the matrix intersection. By means of a case study, where data were collected via interview with the Administrative Pro-Rector, who takes part at the elaboration of the strategic planning of the institution, it was possible to infer analysis concerning points which must be prioritized at the internal audit work. We emphasize that the priorities were identified when processed in a system (of academic use). From the study we can conclude that, starting from these information systems, audit can identify priorities on its work program. Along with plans and strategic objectives of the enterprise, the internal auditor can define operational procedures to work in favor of the attainment of the objectives of the organization.

Speech as a breakthrough signaling resource in the cognitive evolution of biological complex adaptive systems.

PubMed

Mattei, Tobias A

2014-12-01

In self-adapting dynamical systems, a significant improvement in the signaling flow among agents constitutes one of the most powerful triggering events for the emergence of new complex behaviors. Ackermann and colleagues' comprehensive phylogenetic analysis of the brain structures involved in acoustic communication provides further evidence of the essential role which speech, as a breakthrough signaling resource, has played in the evolutionary development of human cognition viewed from the standpoint of complex adaptive system analysis.

Tuberous sclerosis complex: Recent advances in manifestations and therapy.

PubMed

Wataya-Kaneda, Mari; Uemura, Motohide; Fujita, Kazutoshi; Hirata, Haruhiko; Osuga, Keigo; Kagitani-Shimono, Kuriko; Nonomura, Norio

2017-09-01

Tuberous sclerosis complex is an autosomal dominant inherited disorder characterized by generalized involvement and variable manifestations with a birth incidence of 1:6000. In a quarter of a century, significant progress in tuberous sclerosis complex has been made. Two responsible genes, TSC1 and TSC2, which encode hamartin and tuberin, respectively, were discovered in the 1990s, and their functions were elucidated in the 2000s. Hamartin-Tuberin complex is involved in the phosphoinositide 3-kinase-protein kinase B-mammalian target of rapamycin signal transduction pathway, and suppresses mammalian target of rapamycin complex 1 activity, which is a center for various functions. Constitutive activation of mammalian target of rapamycin complex 1 causes variable manifestations in tuberous sclerosis complex. Recently, genetic tests were launched to diagnose tuberous sclerosis complex, and mammalian target of rapamycin complex 1 inhibitors are being used to treat tuberous sclerosis complex patients. As a result of these advances, new diagnostic criteria have been established and an indispensable new treatment method; that is, "a cross-sectional medical examination system," a system to involve many experts for tuberous sclerosis complex diagnosis and treatments, was also created. Simultaneously, the frequency of genetic tests and advances in diagnostic technology have resulted in new views on symptoms. The numbers of tuberous sclerosis complex patients without neural symptoms are increasing, and for these patients, renal manifestations and pulmonary lymphangioleiomyomatosis have become important manifestations. New concepts of tuberous sclerosis complex-associated neuropsychiatric disorders or perivascular epithelioid cell tumors are being created. The present review contains a summary of recent advances, significant manifestations and therapy in tuberous sclerosis complex. © 2017 The Japanese Urological Association.

Patients with Parkinson's Disease Learn to Control Complex Systems via Procedural as Well as Non-Procedural Learning

ERIC Educational Resources Information Center

Osman, Magda; Wilkinson, Leonora; Beigi, Mazda; Castaneda, Cristina Sanchez; Jahanshahi, Marjan

2008-01-01

The striatum is considered to mediate some forms of procedural learning. Complex dynamic control (CDC) tasks involve an individual having to make a series of sequential decisions to achieve a specific outcome (e.g. learning to operate and control a car), and they involve procedural learning. The aim of this study was to test the hypothesis that…

Conceptualizing Teacher Identity as a Complex Dynamic System: The Inner Dynamics of Transformations during a Practicum

ERIC Educational Resources Information Center

Henry, Alastair

2016-01-01

Currently, the inner dynamics of teacher identity transformations remain a "black box." Conceptualizing preservice teacher identity as a complex dynamic system, and the notion of "being someone who teaches" in dialogical terms as involving shifts between different teacher voices, the study investigates the dynamical processes…

Using DCOM to support interoperability in forest ecosystem management decision support systems

Treesearch

W.D. Potter; S. Liu; X. Deng; H.M. Rauscher

2000-01-01

Forest ecosystems exhibit complex dynamics over time and space. Management of forest ecosystems involves the need to forecast future states of complex systems that are often undergoing structural changes. This in turn requires integration of quantitative science and engineering components with sociopolitical, regulatory, and economic considerations. The amount of data...

Autonomous perception and decision making in cyber-physical systems

NASA Astrophysics Data System (ADS)

Sarkar, Soumik

2011-07-01

The cyber-physical system (CPS) is a relatively new interdisciplinary technology area that includes the general class of embedded and hybrid systems. CPSs require integration of computation and physical processes that involves the aspects of physical quantities such as time, energy and space during information processing and control. The physical space is the source of information and the cyber space makes use of the generated information to make decisions. This dissertation proposes an overall architecture of autonomous perception-based decision & control of complex cyber-physical systems. Perception involves the recently developed framework of Symbolic Dynamic Filtering for abstraction of physical world in the cyber space. For example, under this framework, sensor observations from a physical entity are discretized temporally and spatially to generate blocks of symbols, also called words that form a language. A grammar of a language is the set of rules that determine the relationships among words to build sentences. Subsequently, a physical system is conjectured to be a linguistic source that is capable of generating a specific language. The proposed technology is validated on various (experimental and simulated) case studies that include health monitoring of aircraft gas turbine engines, detection and estimation of fatigue damage in polycrystalline alloys, and parameter identification. Control of complex cyber-physical systems involve distributed sensing, computation, control as well as complexity analysis. A novel statistical mechanics-inspired complexity analysis approach is proposed in this dissertation. In such a scenario of networked physical systems, the distribution of physical entities determines the underlying network topology and the interaction among the entities forms the abstract cyber space. It is envisioned that the general contributions, made in this dissertation, will be useful for potential application areas such as smart power grids and buildings, distributed energy systems, advanced health care procedures and future ground and air transportation systems.

Participatory Design, User Involvement and Health IT Evaluation.

PubMed

Kushniruk, Andre; Nøhr, Christian

2016-01-01

End user involvement and input into the design and evaluation of information systems has been recognized as being a critical success factor in the adoption of information systems. Nowhere is this need more critical than in the design of health information systems. Consistent with evidence from the general software engineering literature, the degree of user input into design of complex systems has been identified as one of the most important factors in the success or failure of complex information systems. The participatory approach goes beyond user-centered design and co-operative design approaches to include end users as more active participants in design ideas and decision making. Proponents of participatory approaches argue for greater end user participation in both design and evaluative processes. Evidence regarding the effectiveness of increased user involvement in design is explored in this contribution in the context of health IT. The contribution will discuss several approaches to including users in design and evaluation. Challenges in IT evaluation during participatory design will be described and explored along with several case studies.

A system performance throughput model applicable to advanced manned telescience systems

NASA Technical Reports Server (NTRS)

Haines, Richard F.

1990-01-01

As automated space systems become more complex, autonomous, and opaque to the flight crew, it becomes increasingly difficult to determine whether the total system is performing as it should. Some of the complex and interrelated human performance measurement issues are addressed that are related to total system validation. An evaluative throughput model is presented which can be used to generate a human operator-related benchmark or figure of merit for a given system which involves humans at the input and output ends as well as other automated intelligent agents. The concept of sustained and accurate command/control data information transfer is introduced. The first two input parameters of the model involve nominal and off-nominal predicted events. The first of these calls for a detailed task analysis while the second is for a contingency event assessment. The last two required input parameters involving actual (measured) events, namely human performance and continuous semi-automated system performance. An expression combining these four parameters was found using digital simulations and identical, representative, random data to yield the smallest variance.

Marr's levels and the minimalist program.

PubMed

Johnson, Mark

2017-02-01

A simple change to a cognitive system at Marr's computational level may entail complex changes at the other levels of description of the system. The implementational level complexity of a change, rather than its computational level complexity, may be more closely related to the plausibility of a discrete evolutionary event causing that change. Thus the formal complexity of a change at the computational level may not be a good guide to the plausibility of an evolutionary event introducing that change. For example, while the Minimalist Program's Merge is a simple formal operation (Berwick & Chomsky, 2016), the computational mechanisms required to implement the language it generates (e.g., to parse the language) may be considerably more complex. This has implications for the theory of grammar: theories of grammar which involve several kinds of syntactic operations may be no less evolutionarily plausible than a theory of grammar that involves only one. A deeper understanding of human language at the algorithmic and implementational levels could strengthen Minimalist Program's account of the evolution of language.

Undecidability and Irreducibility Conditions for Open-Ended Evolution and Emergence.

PubMed

Hernández-Orozco, Santiago; Hernández-Quiroz, Francisco; Zenil, Hector

2018-01-01

Is undecidability a requirement for open-ended evolution (OEE)? Using methods derived from algorithmic complexity theory, we propose robust computational definitions of open-ended evolution and the adaptability of computable dynamical systems. Within this framework, we show that decidability imposes absolute limits on the stable growth of complexity in computable dynamical systems. Conversely, systems that exhibit (strong) open-ended evolution must be undecidable, establishing undecidability as a requirement for such systems. Complexity is assessed in terms of three measures: sophistication, coarse sophistication, and busy beaver logical depth. These three complexity measures assign low complexity values to random (incompressible) objects. As time grows, the stated complexity measures allow for the existence of complex states during the evolution of a computable dynamical system. We show, however, that finding these states involves undecidable computations. We conjecture that for similar complexity measures that assign low complexity values, decidability imposes comparable limits on the stable growth of complexity, and that such behavior is necessary for nontrivial evolutionary systems. We show that the undecidability of adapted states imposes novel and unpredictable behavior on the individuals or populations being modeled. Such behavior is irreducible. Finally, we offer an example of a system, first proposed by Chaitin, that exhibits strong OEE.

On Chaotic and Hyperchaotic Complex Nonlinear Dynamical Systems

NASA Astrophysics Data System (ADS)

Mahmoud, Gamal M.

Dynamical systems described by real and complex variables are currently one of the most popular areas of scientific research. These systems play an important role in several fields of physics, engineering, and computer sciences, for example, laser systems, control (or chaos suppression), secure communications, and information science. Dynamical basic properties, chaos (hyperchaos) synchronization, chaos control, and generating hyperchaotic behavior of these systems are briefly summarized. The main advantage of introducing complex variables is the reduction of phase space dimensions by a half. They are also used to describe and simulate the physics of detuned laser and thermal convection of liquid flows, where the electric field and the atomic polarization amplitudes are both complex. Clearly, if the variables of the system are complex the equations involve twice as many variables and control parameters, thus making it that much harder for a hostile agent to intercept and decipher the coded message. Chaotic and hyperchaotic complex systems are stated as examples. Finally there are many open problems in the study of chaotic and hyperchaotic complex nonlinear dynamical systems, which need further investigations. Some of these open problems are given.

Sensitivity based coupling strengths in complex engineering systems

NASA Technical Reports Server (NTRS)

Bloebaum, C. L.; Sobieszczanski-Sobieski, J.

1993-01-01

The iterative design scheme necessary for complex engineering systems is generally time consuming and difficult to implement. Although a decomposition approach results in a more tractable problem, the inherent couplings make establishing the interdependencies of the various subsystems difficult. Another difficulty lies in identifying the most efficient order of execution for the subsystem analyses. The paper describes an approach for determining the dependencies that could be suspended during the system analysis with minimal accuracy losses, thereby reducing the system complexity. A new multidisciplinary testbed is presented, involving the interaction of structures, aerodynamics, and performance disciplines. Results are presented to demonstrate the effectiveness of the system reduction scheme.

Solute transport with equilibrium aqueous complexation and either sorption or ion exchange: Simulation methodology and applications

USGS Publications Warehouse

Lewis, F.M.; Voss, C.I.; Rubin, J.

1987-01-01

Methodologies that account for specific types of chemical reactions in the simulation of solute transport can be developed so they are compatible with solution algorithms employed in existing transport codes. This enables the simulation of reactive transport in complex multidimensional flow regimes, and provides a means for existing codes to account for some of the fundamental chemical processes that occur among transported solutes. Two equilibrium-controlled reaction systems demonstrate a methodology for accommodating chemical interaction into models of solute transport. One system involves the sorption of a given chemical species, as well as two aqueous complexations in which the sorbing species is a participant. The other reaction set involves binary ion exchange coupled with aqueous complexation involving one of the exchanging species. The methodology accommodates these reaction systems through the addition of nonlinear terms to the transport equations for the sorbing species. Example simulation results show (1) the effect equilibrium chemical parameters have on the spatial distributions of concentration for complexing solutes; (2) that an interrelationship exists between mechanical dispersion and the various reaction processes; (3) that dispersive parameters of the porous media cannot be determined from reactive concentration distributions unless the reaction is accounted for or the influence of the reaction is negligible; (4) how the concentration of a chemical species may be significantly affected by its participation in an aqueous complex with a second species which also sorbs; and (5) that these coupled chemical processes influencing reactive transport can be demonstrated in two-dimensional flow regimes. ?? 1987.

Complexity in Vocational Education and Training Governance

ERIC Educational Resources Information Center

Oliver, Damian

2010-01-01

Complexity is a feature common to all vocational education and training (VET) governance arrangements, due to the wide range of students VET systems caters for, and the number of stakeholders involved in both decision making and funding and financing. In this article, Pierre and Peter's framework of governance is used to examine complexity in VET…

Ephemeral collision complexes mediate chemically termolecular transformations that affect system chemistry [Ephemeral collision complexes induce chemically termolecular transformations that affect global chemistry

DOE PAGES

Burke, Michael P.; Klippenstein, Stephen J.

2017-08-14

Termolecular association reactions involve ephemeral collision complexes—formed from the collision of two molecules—that collide with a third and chemically inert ‘bath gas’ molecule that simply transfers energy to/from the complex. These collision complexes are generally not thought to react chemically on collision with a third molecule in the gas-phase systems of combustion and planetary atmospheres. Such ‘chemically termolecular’ reactions, in which all three molecules are involved in bond making and/or breaking, were hypothesized long ago in studies establishing radical chain branching mechanisms, but were later concluded to be unimportant. Here, with data from ab initio master equation and kinetic-transport simulations,more » we reveal that reactions of H+O 2 collision complexes with other radicals constitute major kinetic pathways under common combustion situations. These reactions are also found to influence flame propagation speeds, a common measure of global reactivity. As a result, analogous chemically termolecular reactions mediated by ephemeral collision complexes are probably of significance in various combustion and planetary environments.« less

Ephemeral collision complexes mediate chemically termolecular transformations that affect system chemistry [Ephemeral collision complexes induce chemically termolecular transformations that affect global chemistry

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

Burke, Michael P.; Klippenstein, Stephen J.

Termolecular association reactions involve ephemeral collision complexes—formed from the collision of two molecules—that collide with a third and chemically inert ‘bath gas’ molecule that simply transfers energy to/from the complex. These collision complexes are generally not thought to react chemically on collision with a third molecule in the gas-phase systems of combustion and planetary atmospheres. Such ‘chemically termolecular’ reactions, in which all three molecules are involved in bond making and/or breaking, were hypothesized long ago in studies establishing radical chain branching mechanisms, but were later concluded to be unimportant. Here, with data from ab initio master equation and kinetic-transport simulations,more » we reveal that reactions of H+O 2 collision complexes with other radicals constitute major kinetic pathways under common combustion situations. These reactions are also found to influence flame propagation speeds, a common measure of global reactivity. As a result, analogous chemically termolecular reactions mediated by ephemeral collision complexes are probably of significance in various combustion and planetary environments.« less

Topical Rapamycin Therapy to Alleviate Cutaneous Manifestations of Tuberous Sclerosis Complex

DTIC Science & Technology

2015-05-01

AD Award Number: W81XWH-11-1-0240 Title: Topical Rapamycin Therapy to Alleviate Cutaneous Manifestations of Tuberous Sclerosis Complex Principal...1Sep2011 - 28Feb2015 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Topical Rapamycin Therapy to Alleviate Cutaneous Manifestations of Tuberous Sclerosis...organ systems. The TSC1 and TSC2 gene products are involved in cell signaling; in particular they are involved in the mammalian target of rapamycin

Collaborative Systems Testing

ERIC Educational Resources Information Center

Pocatilu, Paul; Ciurea, Cristian

2009-01-01

Collaborative systems are widely used today in various activity fields. Their complexity is high and the development involves numerous resources and costs. Testing collaborative systems has a very important role for the systems' success. In this paper we present taxonomy of collaborative systems. The collaborative systems are classified in many…

Dynamics of nanoparticle-protein corona complex formation: analytical results from population balance equations.

PubMed

Darabi Sahneh, Faryad; Scoglio, Caterina; Riviere, Jim

2013-01-01

Nanoparticle-protein corona complex formation involves absorption of protein molecules onto nanoparticle surfaces in a physiological environment. Understanding the corona formation process is crucial in predicting nanoparticle behavior in biological systems, including applications of nanotoxicology and development of nano drug delivery platforms. This paper extends the modeling work in to derive a mathematical model describing the dynamics of nanoparticle corona complex formation from population balance equations. We apply nonlinear dynamics techniques to derive analytical results for the composition of nanoparticle-protein corona complex, and validate our results through numerical simulations. The model presented in this paper exhibits two phases of corona complex dynamics. In the first phase, proteins rapidly bind to the free surface of nanoparticles, leading to a metastable composition. During the second phase, continuous association and dissociation of protein molecules with nanoparticles slowly changes the composition of the corona complex. Given sufficient time, composition of the corona complex reaches an equilibrium state of stable composition. We find analytical approximate formulae for metastable and stable compositions of corona complex. Our formulae are very well-structured to clearly identify important parameters determining corona composition. The dynamics of biocorona formation constitute vital aspect of interactions between nanoparticles and living organisms. Our results further understanding of these dynamics through quantitation of experimental conditions, modeling results for in vitro systems to better predict behavior for in vivo systems. One potential application would involve a single cell culture medium related to a complex protein medium, such as blood or tissue fluid.

Global Hawk Systems Engineering. Case Study

DTIC Science & Technology

2010-01-01

Management Core System ( TBMCS ) (complex software development) • F-111 Fighter (joint program with significant involvement by the Office of the...Software Requirements Specification TACC Tailored Airworthiness Certification Criteria TBMCS Theater Battle Management Core System TEMP Test and

Aeropropulsion 1987. Session 2: Aeropropulsion Structures Research

NASA Technical Reports Server (NTRS)

1987-01-01

Aeropropulsion systems present unique problems to the structural engineer. The extremes in operating temperatures, rotational effects, and behaviors of advanced material systems combine into complexities that require advances in many scientific disciplines involved in structural analysis and design procedures. This session provides an overview of the complexities of aeropropulsion structures and the theoretical, computational, and experimental research conducted to achieve the needed advances.

Toddlers' Complex Communication: Playfulness from a Secure Base

ERIC Educational Resources Information Center

Alcock, Sophie

2013-01-01

Attachment theory is presented in this article as involving embodied relational processes within complex relational systems. Two narrative-like "events" are represented to illustrate very young children playfully relating -- connecting and communicating inter- and intrasubjectively. The ethnographic-inspired research methods included…

On a Possible Unified Scaling Law for Volcanic Eruption Durations

PubMed Central

Cannavò, Flavio; Nunnari, Giuseppe

2016-01-01

Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour. PMID:26926425

On a Possible Unified Scaling Law for Volcanic Eruption Durations.

PubMed

Cannavò, Flavio; Nunnari, Giuseppe

2016-03-01

Volcanoes constitute dissipative systems with many degrees of freedom. Their eruptions are the result of complex processes that involve interacting chemical-physical systems. At present, due to the complexity of involved phenomena and to the lack of precise measurements, both analytical and numerical models are unable to simultaneously include the main processes involved in eruptions thus making forecasts of volcanic dynamics rather unreliable. On the other hand, accurate forecasts of some eruption parameters, such as the duration, could be a key factor in natural hazard estimation and mitigation. Analyzing a large database with most of all the known volcanic eruptions, we have determined that the duration of eruptions seems to be described by a universal distribution which characterizes eruption duration dynamics. In particular, this paper presents a plausible global power-law distribution of durations of volcanic eruptions that holds worldwide for different volcanic environments. We also introduce a new, simple and realistic pipe model that can follow the same found empirical distribution. Since the proposed model belongs to the family of the self-organized systems it may support the hypothesis that simple mechanisms can lead naturally to the emergent complexity in volcanic behaviour.

Problem solving using soft systems methodology.

PubMed

Land, L

This article outlines a method of problem solving which considers holistic solutions to complex problems. Soft systems methodology allows people involved in the problem situation to have control over the decision-making process.

Experimental and theoretical identification of a four- acoustic-inputs/two-vibration-outputs hearing system

NASA Astrophysics Data System (ADS)

Balaji, P. A.

1999-07-01

A cricket's ear is a directional acoustic sensor. It has a remarkable level of sensitivity to the direction of sound propagation in a narrow frequency bandwidth of 4-5 KHz. Because of its complexity, the directional sensitivity has long intrigued researchers. The cricket's ear is a four-acoustic-inputs/two-vibration-outputs system. In this dissertation, this system is examined in depth, both experimentally and theoretically, with a primary goal to understand the mechanics involved in directional hearing. Experimental identification of the system is done by using random signal processing techniques. Theoretical identification of the system is accomplished by analyzing sound transmission through complex trachea of the ear. Finally, a description of how the cricket achieves directional hearing sensitivity is proposed. The fundamental principle involved in directional heating of the cricket has been utilized to design a device to obtain a directional signal from non- directional inputs.

Electromagnetic game modeling through Tensor Analysis of Networks and Game Theory

NASA Astrophysics Data System (ADS)

Maurice, Olivier; Reineix, Alain; Lalléchère, Sébastien

2014-10-01

A complex system involves events coming from natural behaviors. Whatever is the complicated face of machines, they are still far from the complexity of natural systems. Currently, economy is one of the rare science trying to find out some ways to model human behavior. These attempts involve game theory and psychology. Our purpose is to develop a formalism able to take in charge both game and hardware modeling. We first present the Tensorial Analysis of Networks, used for the material part of the system. Then, we detail the mathematical objects defined in order to describe the evolution of the system and its gaming side. To illustrate the discussion we consider the case of a drone whose electronic can be disturbed by a radar field, but this drone must fly as near as possible close to this radar.

China’s Emerging Capabilities in Energy Technology Innovation and Development

DTIC Science & Technology

2015-01-22

management of tempo, scaling, and cost reduction. For particularly complex energy technology systems, such as civilian nuclear power plants , the...technology systems, such as civilian nuclear power plants , the greatest challenges often involve not so much new technology development (a...are far more complex phenomena unfolding than simply technology transfer, duplication, and mimicry . Our work has opened up a series of new

JOHNSON NOISE THERMOMETRY FOR DRIFT-FREE MEASUREMENTS

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

Britton Jr, Charles L; Ezell, N Dianne Bull; Roberts, Michael

In order for Johnson Noise Thermometry (JNT) to be beneficial to SMR designers, it must offer advantages beyond the current state-of-the-art technology. Comparisons to traditional RTDs and thermocouples will involve life-cycle costs, installation footprint, reliability, and accuracy. With JNT, there is additional equipment beyond what is required for the traditional RTD measurement. Therefore, the JNT-RTD system will involve additional complexity and this additional complexity must be justified. Operators will want to know that the measurement is reliable and trustworthy. It is also important that the sensor involve little, if any, additional ongoing maintenance work and that it has a lowmore » probability of causing any malfunction of the primary measurement channel. If these features can be successfully demonstrated, the JNT-RTD system could potentially save money and increase plant reliability.« less

Reading, Complexity and the Brain

ERIC Educational Resources Information Center

Goswami, Usha

2008-01-01

Brain imaging offers a new technology for understanding the acquisition of reading by children. It can contribute novel evidence concerning the key mechanisms supporting reading, and the brain systems that are involved. The extensive neural architecture that develops to support efficient reading testifies to the complex developmental processes…

Expanding the Reach of Physics-Engaging Students in Interdisciplinary Research Involving complex, real-world situation

NASA Astrophysics Data System (ADS)

Bililign, Solomon

2014-03-01

Physics plays a very important role in most interdisciplinary efforts and can provide a solid foundation for students. Retention of students in STEM areas can be facilitated by enhanced interdisciplinary education and research since students are strongly attracted to research with societal relevance and show increasing enthusiasm about problems that have practical consequences. One such area of research is a collaborative Earth System Science. The Earth System is dynamic and complex. It is comprised of diverse components that interact. By providing students the opportunities to work in interdisciplinary groups on a problem that reflects a complex, real-world situation they can see the linkages between components of the Earth system that encompass climate and all its components (weather precipitation, temperature, etc.) and technology development and deployment of sensors and sensor networks and social impacts. By involving students in the creation of their own personalized professional development plan, students are more focused and engaged and are more likely to remain in the program.

An Algorithm for Integrated Subsystem Embodiment and System Synthesis

NASA Technical Reports Server (NTRS)

Lewis, Kemper

1997-01-01

Consider the statement,'A system has two coupled subsystems, one of which dominates the design process. Each subsystem consists of discrete and continuous variables, and is solved using sequential analysis and solution.' To address this type of statement in the design of complex systems, three steps are required, namely, the embodiment of the statement in terms of entities on a computer, the mathematical formulation of subsystem models, and the resulting solution and system synthesis. In complex system decomposition, the subsystems are not isolated, self-supporting entities. Information such as constraints, goals, and design variables may be shared between entities. But many times in engineering problems, full communication and cooperation does not exist, information is incomplete, or one subsystem may dominate the design. Additionally, these engineering problems give rise to mathematical models involving nonlinear functions of both discrete and continuous design variables. In this dissertation an algorithm is developed to handle these types of scenarios for the domain-independent integration of subsystem embodiment, coordination, and system synthesis using constructs from Decision-Based Design, Game Theory, and Multidisciplinary Design Optimization. Implementation of the concept in this dissertation involves testing of the hypotheses using example problems and a motivating case study involving the design of a subsonic passenger aircraft.

Inhibition during response preparation is sensitive to response complexity

PubMed Central

Saks, Dylan; Hoang, Timothy; Ivry, Richard B.

2015-01-01

Motor system excitability is transiently suppressed during the preparation of movement. This preparatory inhibition is hypothesized to facilitate response selection and initiation. Given that demands on selection and initiation processes increase with movement complexity, we hypothesized that complexity would influence preparatory inhibition. To test this hypothesis, we probed corticospinal excitability during a delayed-response task in which participants were cued to prepare right- or left-hand movements of varying complexity. Single-pulse transcranial magnetic stimulation was applied over right primary motor cortex to elicit motor evoked potentials (MEPs) from the first dorsal interosseous (FDI) of the left hand. MEP suppression was greater during the preparation of responses involving coordination of the FDI and adductor digiti minimi relative to easier responses involving only the FDI, independent of which hand was cued to respond. In contrast, this increased inhibition was absent when the complex responses required sequential movements of the two muscles. Moreover, complexity did not influence the level of inhibition when the response hand was fixed for the trial block, regardless of whether the complex responses were performed simultaneously or sequentially. These results suggest that preparatory inhibition contributes to response selection, possibly by suppressing extraneous movements when responses involve the simultaneous coordination of multiple effectors. PMID:25717168

The 1992 annual report on scientific programs: A broad research program on the sciences of complexity

NASA Astrophysics Data System (ADS)

In 1992 the Santa Fe Institute hosted more than 100 short- and long-term research visitors who conducted a total of 212 person-months of residential research in complex systems. To date this 1992 work has resulted in more than 50 SFI Working Papers and nearly 150 publications in the scientific literature. The Institute's book series in the sciences of complexity continues to grow, now numbering more than 20 volumes. The fifth annual complex systems summer school brought nearly 60 graduate students and postdoctoral fellows to Santa Fe for an intensive introduction to the field. Research on complex systems - the focus of work at SFI - involves an extraordinary range of topics normally studied in seemingly disparate fields. Natural systems displaying complex adaptive behavior range upwards from DNA through cells and evolutionary systems to human societies. Research models exhibiting complex behavior include spin glasses, cellular automata, and genetic algorithms. Some of the major questions facing complex systems researchers are: (1) explaining how complexity arises from the nonlinear interaction of simple components; (2) describing the mechanisms underlying high-level aggregate behavior of complex systems (such as the overt behavior of an organism, the flow of energy in an ecology, and the Gross National Product (GNP) of an economy); and (3) creating a theoretical framework to enable predictions about the likely behavior of such systems in various conditions.

1992 annual report on scientific programs: A broad research program on the sciences of complexity

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

Not Available

1992-12-31

In 1992 the Santa Fe Institute hosted more than 100 short- and long-term research visitors who conducted a total of 212 person-months of residential research in complex systems. To date this 1992 work has resulted in more than 50 SFI Working Papers and nearly 150 publications in the scientific literature. The Institute`s book series in the sciences of complexity continues to grow, now numbering more than 20 volumes. The fifth annual complex systems summer school brought nearly 60 graduate students and postdoctoral fellows to Santa Fe for an intensive introduction to the field. Research on complex systems-the focus of workmore » at SFI-involves an extraordinary range of topics normally studied in seemingly disparate fields. Natural systems displaying complex adaptive behavior range upwards from DNA through cells and evolutionary systems to human societies. Research models exhibiting complex behavior include spin glasses, cellular automata, and genetic algorithms. Some of the major questions facing complex systems researchers are: (1) explaining how complexity arises from the nonlinear interaction of simple components; (2) describing the mechanisms underlying high-level aggregate behavior of complex systems (such as the overt behavior of an organism, the flow of energy in an ecology, the GNP of an economy); and (3) creating a theoretical framework to enable predictions about the likely behavior of such systems in various conditions.« less

Dynamical complexity of short and noisy time series. Compression-Complexity vs. Shannon entropy

NASA Astrophysics Data System (ADS)

Nagaraj, Nithin; Balasubramanian, Karthi

2017-07-01

Shannon entropy has been extensively used for characterizing complexity of time series arising from chaotic dynamical systems and stochastic processes such as Markov chains. However, for short and noisy time series, Shannon entropy performs poorly. Complexity measures which are based on lossless compression algorithms are a good substitute in such scenarios. We evaluate the performance of two such Compression-Complexity Measures namely Lempel-Ziv complexity (LZ) and Effort-To-Compress (ETC) on short time series from chaotic dynamical systems in the presence of noise. Both LZ and ETC outperform Shannon entropy (H) in accurately characterizing the dynamical complexity of such systems. For very short binary sequences (which arise in neuroscience applications), ETC has higher number of distinct complexity values than LZ and H, thus enabling a finer resolution. For two-state ergodic Markov chains, we empirically show that ETC converges to a steady state value faster than LZ. Compression-Complexity measures are promising for applications which involve short and noisy time series.

Dynamics of Nanoparticle-Protein Corona Complex Formation: Analytical Results from Population Balance Equations

PubMed Central

Darabi Sahneh, Faryad; Scoglio, Caterina; Riviere, Jim

2013-01-01

Background Nanoparticle-protein corona complex formation involves absorption of protein molecules onto nanoparticle surfaces in a physiological environment. Understanding the corona formation process is crucial in predicting nanoparticle behavior in biological systems, including applications of nanotoxicology and development of nano drug delivery platforms. Method This paper extends the modeling work in to derive a mathematical model describing the dynamics of nanoparticle corona complex formation from population balance equations. We apply nonlinear dynamics techniques to derive analytical results for the composition of nanoparticle-protein corona complex, and validate our results through numerical simulations. Results The model presented in this paper exhibits two phases of corona complex dynamics. In the first phase, proteins rapidly bind to the free surface of nanoparticles, leading to a metastable composition. During the second phase, continuous association and dissociation of protein molecules with nanoparticles slowly changes the composition of the corona complex. Given sufficient time, composition of the corona complex reaches an equilibrium state of stable composition. We find analytical approximate formulae for metastable and stable compositions of corona complex. Our formulae are very well-structured to clearly identify important parameters determining corona composition. Conclusion The dynamics of biocorona formation constitute vital aspect of interactions between nanoparticles and living organisms. Our results further understanding of these dynamics through quantitation of experimental conditions, modeling results for in vitro systems to better predict behavior for in vivo systems. One potential application would involve a single cell culture medium related to a complex protein medium, such as blood or tissue fluid. PMID:23741371

Phonological similarity effect in complex span task.

PubMed

Camos, Valérie; Mora, Gérôme; Barrouillet, Pierre

2013-01-01

The aim of our study was to test the hypothesis that two systems are involved in verbal working memory; one is specifically dedicated to the maintenance of phonological representations through verbal rehearsal while the other would maintain multimodal representations through attentional refreshing. This theoretical framework predicts that phonologically related phenomena such as the phonological similarity effect (PSE) should occur when the domain-specific system is involved in maintenance, but should disappear when concurrent articulation hinders its use. Impeding maintenance in the domain-general system by a concurrent attentional demand should impair recall performance without affecting PSE. In three experiments, we manipulated the concurrent articulation and the attentional demand induced by the processing component of complex span tasks in which participants had to maintain lists of either similar or dissimilar words. Confirming our predictions, PSE affected recall performance in complex span tasks. Although both the attentional demand and the articulatory requirement of the concurrent task impaired recall, only the induction of an articulatory suppression during maintenance made the PSE disappear. These results suggest a duality in the systems devoted to verbal maintenance in the short term, constraining models of working memory.

Using activity theory to study cultural complexity in medical education.

PubMed

Frambach, Janneke M; Driessen, Erik W; van der Vleuten, Cees P M

2014-06-01

There is a growing need for research on culture, cultural differences and cultural effects of globalization in medical education, but these are complex phenomena to investigate. Socio-cultural activity theory seems a useful framework to study cultural complexity, because it matches current views on culture as a dynamic process situated in a social context, and has been valued in diverse fields for yielding rich understandings of complex issues and key factors involved. This paper explains how activity theory can be used in (cross-)cultural medical education research. We discuss activity theory's theoretical background and principles, and we show how these can be applied to the cultural research practice by discussing the steps involved in a cross-cultural study that we conducted, from formulating research questions to drawing conclusions. We describe how the activity system, the unit of analysis in activity theory, can serve as an organizing principle to grasp cultural complexity. We end with reflections on the theoretical and practical use of activity theory for cultural research and note that it is not a shortcut to capture cultural complexity: it is a challenge for researchers to determine the boundaries of their study and to analyze and interpret the dynamics of the activity system.

Holistic School Leadership: Systems Thinking as an Instructional Leadership Enabler

ERIC Educational Resources Information Center

Shaked, Haim; Schechter, Chen

2016-01-01

As instructional leadership involves attempts to understand and improve complex systems, this study explored principals' perceptions regarding possible contributions of systems thinking to instructional leadership. Based on a qualitative analysis, systems thinking was perceived by middle and high school principals to contribute to the following…

Modeling of Wildlife-Associated Zoonoses: Applications and Caveats

PubMed Central

Lewis, Bryan L.; Marathe, Madhav; Eubank, Stephen; Blackburn, Jason K.

2012-01-01

Abstract Wildlife species are identified as an important source of emerging zoonotic disease. Accordingly, public health programs have attempted to expand in scope to include a greater focus on wildlife and its role in zoonotic disease outbreaks. Zoonotic disease transmission dynamics involving wildlife are complex and nonlinear, presenting a number of challenges. First, empirical characterization of wildlife host species and pathogen systems are often lacking, and insight into one system may have little application to another involving the same host species and pathogen. Pathogen transmission characterization is difficult due to the changing nature of population size and density associated with wildlife hosts. Infectious disease itself may influence wildlife population demographics through compensatory responses that may evolve, such as decreased age to reproduction. Furthermore, wildlife reservoir dynamics can be complex, involving various host species and populations that may vary in their contribution to pathogen transmission and persistence over space and time. Mathematical models can provide an important tool to engage these complex systems, and there is an urgent need for increased computational focus on the coupled dynamics that underlie pathogen spillover at the human–wildlife interface. Often, however, scientists conducting empirical studies on emerging zoonotic disease do not have the necessary skill base to choose, develop, and apply models to evaluate these complex systems. How do modeling frameworks differ and what considerations are important when applying modeling tools to the study of zoonotic disease? Using zoonotic disease examples, we provide an overview of several common approaches and general considerations important in the modeling of wildlife-associated zoonoses. PMID:23199265

Systems Intelligence Inventory

ERIC Educational Resources Information Center

Törmänen, Juha; Hämäläinen, Raimo P.; Saarinen, Esa

2016-01-01

Purpose: Systems intelligence (SI) (Saarinen and Hämäläinen, 2004) is a construct defined as a person's ability to act intelligently within complex systems involving interaction and feedback. SI relates to our ability to act in systems and reason about systems to adaptively carry out productive actions within and with respect to systems such as…

Patterns of Performance

ERIC Educational Resources Information Center

Eoyang, Glenda H.

2007-01-01

Complex human interactions involve more than just performance toward pre-determined goals. For this reason, systems that measure and seek to improve performance must adapt to a wide range of ever-changing patterns of individual and group behavior. Historically, HPT professionals have recognized these complexities and responded in a variety of…

An experimental study of phase transitions in a complex plasma

NASA Astrophysics Data System (ADS)

Smith, Bernard Albert Thomas, II

In semiconductor manufacturing, contamination due to particulates significantly decreases the yield and quality of device fabrication, therefore increasing the cost of production. Dust particle clouds can be found in almost all plasma processing environments including both plasma etching devices and in plasma deposition processes. Dust particles suspended within such plasmas will acquire an electric charge from collisions with free electrons in the plasma. If the ratio of inter-particle potential energy to the average kinetic energy is sufficient, the particles will form either a "liquid" structure with short range ordering or a crystalline structure with long range ordering. Otherwise, the dust particle system will remain in a gaseous state. Many experiments have been conducted over the past decade on such complex plasmas to discover the character of the systems formed, but more work is needed to fully understand these structures. This paper describes the processes involved in setting up the CASPER GEC RF Reference Cell and the modifications necessary to examine complex plasmas. Research conducted to characterize the system is outlined to demonstrate that the CASPER Cell behaves as other GEC Cells. In addition, further research performed shows the behavior of the complex plasma system in the CASPER Cell is similar to complex plasmas studied by other groups in this field. Along the way analysis routines developed specifically for this system are described. New research involving polydisperse dust distributions is carried out in the system once the initial characterization is finished. Next, a system to externally vary the DC bias in the CASPER Cell is developed and characterized. Finally, new research conducted to specifically examine how the complex plasma system reacts to a variable DC bias is reported. Specifically, the response of the interparticle spacing to various system parameters (including the external DC bias) is examined. Also, a previously unreported phenomenon, namely layer splitting, is examined.

Cognitive engineering models: A prerequisite to the design of human-computer interaction in complex dynamic systems

NASA Technical Reports Server (NTRS)

Mitchell, Christine M.

1993-01-01

This chapter examines a class of human-computer interaction applications, specifically the design of human-computer interaction for the operators of complex systems. Such systems include space systems (e.g., manned systems such as the Shuttle or space station, and unmanned systems such as NASA scientific satellites), aviation systems (e.g., the flight deck of 'glass cockpit' airplanes or air traffic control) and industrial systems (e.g., power plants, telephone networks, and sophisticated, e.g., 'lights out,' manufacturing facilities). The main body of human-computer interaction (HCI) research complements but does not directly address the primary issues involved in human-computer interaction design for operators of complex systems. Interfaces to complex systems are somewhat special. The 'user' in such systems - i.e., the human operator responsible for safe and effective system operation - is highly skilled, someone who in human-machine systems engineering is sometimes characterized as 'well trained, well motivated'. The 'job' or task context is paramount and, thus, human-computer interaction is subordinate to human job interaction. The design of human interaction with complex systems, i.e., the design of human job interaction, is sometimes called cognitive engineering.

Dependency visualization for complex system understanding

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

Smart, J. Allison Cory

1994-09-01

With the volume of software in production use dramatically increasing, the importance of software maintenance has become strikingly apparent. Techniques now sought and developed for reverse engineering and design extraction and recovery. At present, numerous commercial products and research tools exist which are capable of visualizing a variety of programming languages and software constructs. The list of new tools and services continues to grow rapidly. Although the scope of the existing commercial and academic product set is quite broad, these tools still share a common underlying problem. The ability of each tool to visually organize object representations is increasingly impairedmore » as the number of components and component dependencies within systems increases. Regardless of how objects are defined, complex ``spaghetti`` networks result in nearly all large system cases. While this problem is immediately apparent in modem systems analysis involving large software implementations, it is not new. As will be discussed in Chapter 2, related problems involving the theory of graphs were identified long ago. This important theoretical foundation provides a useful vehicle for representing and analyzing complex system structures. While the utility of directed graph based concepts in software tool design has been demonstrated in literature, these tools still lack the capabilities necessary for large system comprehension. This foundation must therefore be expanded with new organizational and visualization constructs necessary to meet this challenge. This dissertation addresses this need by constructing a conceptual model and a set of methods for interactively exploring, organizing, and understanding the structure of complex software systems.« less

XML Encoding of Features Describing Rule-Based Modeling of Reaction Networks with Multi-Component Molecular Complexes

PubMed Central

Blinov, Michael L.; Moraru, Ion I.

2011-01-01

Multi-state molecules and multi-component complexes are commonly involved in cellular signaling. Accounting for molecules that have multiple potential states, such as a protein that may be phosphorylated on multiple residues, and molecules that combine to form heterogeneous complexes located among multiple compartments, generates an effect of combinatorial complexity. Models involving relatively few signaling molecules can include thousands of distinct chemical species. Several software tools (StochSim, BioNetGen) are already available to deal with combinatorial complexity. Such tools need information standards if models are to be shared, jointly evaluated and developed. Here we discuss XML conventions that can be adopted for modeling biochemical reaction networks described by user-specified reaction rules. These could form a basis for possible future extensions of the Systems Biology Markup Language (SBML). PMID:21464833

[A complex interplay of hormones, neuro-transmitters, neuropeptides and immunity cells is responsible for the control of eating].

PubMed

Rondanelli, M

1997-09-01

Food-seeking behaviour is a complex mechanism which involves an interplay of hormones, neurotransmitters, neuropeptides and immunity cells. In this review the important role of the cooperation between the SNC system, the endocrine system and in particular the immune system in the control of eating is underlined. Like stress and depression, in fact the regulation of eating represents another example of the interplay between these three systems and it is secondary to a bidirectional dialogue between the center and the periphery.

1991 Annual report on scientific programs: A broad research program on the sciences of complexity

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

Not Available

1991-01-01

1991 was continued rapid growth for the Santa Fe Institute (SFI) as it broadened its interdisciplinary research into the organization, evolution and operation of complex systems and sought deeply the principles underlying their dynamic behavior. Research on complex systems--the focus of work at SFI--involves an extraordinary range of topics normally studied in seemingly disparate fields. Natural systems displaying complex behavior range upwards from proteins and DNA through cells and evolutionary systems to human societies. Research models exhibiting complexity include nonlinear equations, spin glasses, cellular automata, genetic algorithms, classifier systems, and an array of other computational models. Some of the majormore » questions facing complex systems researchers are: (1) explaining how complexity arises from the nonlinear interaction of simples components, (2) describing the mechanisms underlying high-level aggregate behavior of complex systems (such as the overt behavior of an organism, the flow of energy in an ecology, the GNP of an economy), and (3) creating a theoretical framework to enable predictions about the likely behavior of such systems in various conditions. The importance of understanding such systems in enormous: many of the most serious challenges facing humanity--e.g., environmental sustainability, economic stability, the control of disease--as well as many of the hardest scientific questions--e.g., protein folding, the distinction between self and non-self in the immune system, the nature of intelligence, the origin of life--require deep understanding of complex systems.« less

1991 Annual report on scientific programs: A broad research program on the sciences of complexity

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

Not Available

1991-12-31

1991 was continued rapid growth for the Santa Fe Institute (SFI) as it broadened its interdisciplinary research into the organization, evolution and operation of complex systems and sought deeply the principles underlying their dynamic behavior. Research on complex systems--the focus of work at SFI--involves an extraordinary range of topics normally studied in seemingly disparate fields. Natural systems displaying complex behavior range upwards from proteins and DNA through cells and evolutionary systems to human societies. Research models exhibiting complexity include nonlinear equations, spin glasses, cellular automata, genetic algorithms, classifier systems, and an array of other computational models. Some of the majormore » questions facing complex systems researchers are: (1) explaining how complexity arises from the nonlinear interaction of simples components, (2) describing the mechanisms underlying high-level aggregate behavior of complex systems (such as the overt behavior of an organism, the flow of energy in an ecology, the GNP of an economy), and (3) creating a theoretical framework to enable predictions about the likely behavior of such systems in various conditions. The importance of understanding such systems in enormous: many of the most serious challenges facing humanity--e.g., environmental sustainability, economic stability, the control of disease--as well as many of the hardest scientific questions--e.g., protein folding, the distinction between self and non-self in the immune system, the nature of intelligence, the origin of life--require deep understanding of complex systems.« less

Stupid Tutoring Systems, Intelligent Humans

ERIC Educational Resources Information Center

Baker, Ryan S.

2016-01-01

The initial vision for intelligent tutoring systems involved powerful, multi-faceted systems that would leverage rich models of students and pedagogies to create complex learning interactions. But the intelligent tutoring systems used at scale today are much simpler. In this article, I present hypotheses on the factors underlying this development,…

Illustrations of mathematical modeling in biology: epigenetics, meiosis, and an outlook.

PubMed

Richards, D; Berry, S; Howard, M

2012-01-01

In the past few years, mathematical modeling approaches in biology have begun to fulfill their promise by assisting in the dissection of complex biological systems. Here, we review two recent examples of predictive mathematical modeling in plant biology. The first involves the quantitative epigenetic silencing of the floral repressor gene FLC in Arabidopsis, mediated by a Polycomb-based system. The second involves the spatiotemporal dynamics of telomere bouquet formation in wheat-rye meiosis. Although both the biology and the modeling framework of the two systems are different, both exemplify how mathematical modeling can help to accelerate discovery of the underlying mechanisms in complex biological systems. In both cases, the models that developed were relatively minimal, including only essential features, but both nevertheless yielded fundamental insights. We also briefly review the current state of mathematical modeling in biology, difficulties inherent in its application, and its potential future development.

Secondary Cutaneous Involvement in Follicular Diffuse Lymphoma Treated with Helical Tomotherapy

PubMed Central

Dar, A. Rashid; Jordan, Kevin

2017-01-01

Non-Hodgkin’s lymphoma is a complex heterogeneous group of disease entities that involves nodal and extranodal tissues. Cutaneous involvement can occur either as a primary or secondary in course of disease. Radiation therapy with either total body or localized treatments is often used for local control and symptom relief, depending on the target volume. We describe a 60-year-old male with a remote history of stage IA left neck follicular lymphoma treated with radiation 20 years ago and previous relapses aggressively treated by chemotherapy. Treatment to a large volume of back and posterior shoulders on a helical tomotherapy radiotherapy system is reported. The skin lesions responded completely with no toxicity. Palliative radiotherapy to a fairly large and complex volume of skin with modest dose avoiding underlying critical tissues on tomotherapy is feasible, well tolerated with an excellent durable response, without compromising future chemotherapy and stem cell transplant for systemic relapse. PMID:28944110

Capturing, Codifying and Scoring Complex Data for Innovative, Computer-Based Items.

ERIC Educational Resources Information Center

Luecht, Richard M.

The Microsoft Certification Program (MCP) includes many new computer-based item types, based on complex cases involving the Windows 2000 (registered) operating system. This Innovative Item Technology (IIT) has presented challenges beyond traditional psychometric considerations such as capturing and storing the relevant response data from…

Analysis and design of algorithm-based fault-tolerant systems

NASA Technical Reports Server (NTRS)

Nair, V. S. Sukumaran

1990-01-01

An important consideration in the design of high performance multiprocessor systems is to ensure the correctness of the results computed in the presence of transient and intermittent failures. Concurrent error detection and correction have been applied to such systems in order to achieve reliability. Algorithm Based Fault Tolerance (ABFT) was suggested as a cost-effective concurrent error detection scheme. The research was motivated by the complexity involved in the analysis and design of ABFT systems. To that end, a matrix-based model was developed and, based on that, algorithms for both the design and analysis of ABFT systems are formulated. These algorithms are less complex than the existing ones. In order to reduce the complexity further, a hierarchical approach is developed for the analysis of large systems.

Managed care: employers' influence on the health care system.

PubMed

Corder, K T; Phoon, J; Barter, M

1996-01-01

Health care reform is a complex issue involving many key sectors including providers, consumers, insurers, employers, and the government. System changes must involve all sectors for reform to be effective. Each sector has a responsibility to understand not only its own role in the health care system, but the roles of others as well. The role of business employers is often not apparent to health care providers, especially nurses. Understanding the influence employers have on the health care system is vital if providers want to be proactive change agents ensuring quality care.

Rapamycin-induced oligomer formation system of FRB-FKBP fusion proteins.

PubMed

Inobe, Tomonao; Nukina, Nobuyuki

2016-07-01

Most proteins form larger protein complexes and perform multiple functions in the cell. Thus, artificial regulation of protein complex formation controls the cellular functions that involve protein complexes. Although several artificial dimerization systems have already been used for numerous applications in biomedical research, cellular protein complexes form not only simple dimers but also larger oligomers. In this study, we showed that fusion proteins comprising the induced heterodimer formation proteins FRB and FKBP formed various oligomers upon addition of rapamycin. By adjusting the configuration of fusion proteins, we succeeded in generating an inducible tetramer formation system. Proteins of interest also formed tetramers by fusing to the inducible tetramer formation system, which exhibits its utility in a broad range of biological applications. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Applying observations from technological transformations in complex adaptive systems to inform health policy on technology adoption.

PubMed

Phillips, Andrew B; Merrill, Jacqueline

2012-01-01

Many complex markets such as banking and manufacturing have benefited significantly from technology adoption. Each of these complex markets experienced increased efficiency, quality, security, and customer involvement as a result of technology transformation in their industry. Healthcare has not benefited to the same extent. We provide initial findings from a policy analysis of complex markets and the features of these transformations that can influence health technology adoption and acceptance.

Applying Early Systems Engineering: Injecting Knowledge into the Capability Development Process

DTIC Science & Technology

2012-10-01

involves early use of systems engi- neering and technical analyses to supplement the existing operational analysis techniques currently used in...complexity, and costs of systems now being developed require tight coupling between operational requirements stated in the CDD, system requirements...Fleischer » Keywords: Capability Development, Competitive Prototyping, Knowledge Points, Early Systems Engineering Applying Early Systems

Fort Collins Science Center Ecosystem Dynamics Branch

USGS Publications Warehouse

Wilson, Jim; Melcher, C.; Bowen, Z.

2009-01-01

Complex natural resource issues require understanding a web of interactions among ecosystem components that are (1) interdisciplinary, encompassing physical, chemical, and biological processes; (2) spatially complex, involving movements of animals, water, and airborne materials across a range of landscapes and jurisdictions; and (3) temporally complex, occurring over days, weeks, or years, sometimes involving response lags to alteration or exhibiting large natural variation. Scientists in the Ecosystem Dynamics Branch of the U.S. Geological Survey, Fort Collins Science Center, investigate a diversity of these complex natural resource questions at the landscape and systems levels. This Fact Sheet describes the work of the Ecosystems Dynamics Branch, which is focused on energy and land use, climate change and long-term integrated assessments, herbivore-ecosystem interactions, fire and post-fire restoration, and environmental flows and river restoration.

The Neural Correlates of Emotional Prosody Comprehension: Disentangling Simple from Complex Emotion

PubMed Central

Alba-Ferrara, Lucy; Hausmann, Markus; Mitchell, Rachel L.; Weis, Susanne

2011-01-01

Background Emotional prosody comprehension (EPC), the ability to interpret another person's feelings by listening to their tone of voice, is crucial for effective social communication. Previous studies assessing the neural correlates of EPC have found inconsistent results, particularly regarding the involvement of the medial prefrontal cortex (mPFC). It remained unclear whether the involvement of the mPFC is linked to an increased demand in socio-cognitive components of EPC such as mental state attribution and if basic perceptual processing of EPC can be performed without the contribution of this region. Methods fMRI was used to delineate neural activity during the perception of prosodic stimuli conveying simple and complex emotion. Emotional trials in general, as compared to neutral ones, activated a network comprising temporal and lateral frontal brain regions, while complex emotion trials specifically showed an additional involvement of the mPFC, premotor cortex, frontal operculum and left insula. Conclusion These results indicate that the mPFC and premotor areas might be associated, but are not crucial to EPC. However, the mPFC supports socio-cognitive skills necessary to interpret complex emotion such as inferring mental states. Additionally, the premotor cortex involvement may reflect the participation of the mirror neuron system for prosody processing particularly of complex emotion. PMID:22174872

Closed circuit TV system monitors welding operations

NASA Technical Reports Server (NTRS)

Gilman, M.

1967-01-01

TV camera system that has a special vidicon tube with a gradient density filter is used in remote monitoring of TIG welding of stainless steel. The welding operations involve complex assembly welding tools and skates in areas of limited accessibility.

MHD processes in the outer heliosphere

NASA Technical Reports Server (NTRS)

Burlaga, L. F.

1984-01-01

The magnetic field measurements from Voyager and the magnetohydrodynamic (MHD) processes in the outer heliosphere are reviewed. A bibliography of the experimental and theoretical work concerning magnetic fields and plasmas observed in the outer heliosphere is given. Emphasis in this review is on basic concepts and dynamical processes involving the magnetic field. The theory that serves to explain and unify the interplanetary magnetic field and plasma observations is magnetohydrodynamics. Basic physical processes and observations that relate directly to solutions of the MHD equations are emphasized, but obtaining solutions of this complex system of equations involves various assumptions and approximations. The spatial and temporal complexity of the outer heliosphere and some approaches for dealing with this complexity are discussed.

Structured analysis and modeling of complex systems

NASA Technical Reports Server (NTRS)

Strome, David R.; Dalrymple, Mathieu A.

1992-01-01

The Aircrew Evaluation Sustained Operations Performance (AESOP) facility at Brooks AFB, Texas, combines the realism of an operational environment with the control of a research laboratory. In recent studies we collected extensive data from the Airborne Warning and Control Systems (AWACS) Weapons Directors subjected to high and low workload Defensive Counter Air Scenarios. A critical and complex task in this environment involves committing a friendly fighter against a hostile fighter. Structured Analysis and Design techniques and computer modeling systems were applied to this task as tools for analyzing subject performance and workload. This technology is being transferred to the Man-Systems Division of NASA Johnson Space Center for application to complex mission related tasks, such as manipulating the Shuttle grappler arm.

Uncertainties in building a strategic defense.

PubMed

Zraket, C A

1987-03-27

Building a strategic defense against nuclear ballistic missiles involves complex and uncertain functional, spatial, and temporal relations. Such a defensive system would evolve and grow over decades. It is too complex, dynamic, and interactive to be fully understood initially by design, analysis, and experiments. Uncertainties exist in the formulation of requirements and in the research and design of a defense architecture that can be implemented incrementally and be fully tested to operate reliably. The analysis and measurement of system survivability, performance, and cost-effectiveness are critical to this process. Similar complexities exist for an adversary's system that would suppress or use countermeasures against a missile defense. Problems and opportunities posed by these relations are described, with emphasis on the unique characteristics and vulnerabilities of space-based systems.

Higher Education Provision Using Systems Thinking Approach--Case Studies

ERIC Educational Resources Information Center

Dhukaram, Anandhi Vivekanandan; Sgouropoulou, Cleo; Feldman, Gerald; Amini, Ardavan

2018-01-01

The purpose of this paper is to highlight the complexities involved in higher education provision and how systems thinking and socio-technical systems (STS) thinking approach can be used to understand the education ecosystem. Systems thinking perspective is provided using two case studies: the development of European Learner Mobility (EuroLM)…

Autonomy, Automation, and Systems

NASA Astrophysics Data System (ADS)

Turner, Philip R.

1987-02-01

Aerospace industry interest in autonomy and automation, given fresh impetus by the national goal of establishing a Space Station, is becoming a major item of research and technology development. The promise of new technology arising from research in Artificial Intelligence (AI) has focused much attention on its potential in autonomy and automation. These technologies can improve performance in autonomous control functions that involve planning, scheduling, and fault diagnosis of complex systems. There are, however, many aspects of system and subsystem design in an autonomous system that impact AI applications, but do not directly involve AI technology. Development of a system control architecture, establishment of an operating system within the design, providing command and sensory data collection features appropriate to automated operation, and the use of design analysis tools to support system engineering are specific examples of major design issues. Aspects such as these must also receive attention and technology development support if we are to implement complex autonomous systems within the realistic limitations of mass, power, cost, and available flight-qualified technology that are all-important to a flight project.

Complex socio-technical systems: Characterization and management guidelines.

PubMed

Righi, Angela Weber; Saurin, Tarcisio Abreu

2015-09-01

Although ergonomics has paid increasing attention to the perspective of complexity, methods for its operationalization are scarce. This study introduces a framework for the operationalization of the "attribute view" of complexity, which involves: (i) the delimitation of the socio-technical system (STS); (ii) the description of four complexity attributes, namely a large number of elements in dynamic interactions, a wide diversity of elements, unexpected variability, and resilience; (iii) the assessment of six management guidelines, namely design slack, give visibility to processes and outcomes, anticipate and monitor the impacts of small changes, monitor the gap between prescription and practice, encourage diversity of perspectives when making decisions, and create an environment that supports resilience; and (iv) the identification of leverage points for improving the STS design, based on both the analysis of relationships among the attributes and their classification as irreducible/manageable complexity, and liability/asset. The use of the framework is illustrated by the study of an emergency department of a University hospital. Data collection involved analysis of documents, observations of work at the front-line, interviews with employees, and the application of questionnaires. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Kinetics and mechanism of olefin catalytic hydroalumination by organoaluminum compounds

NASA Astrophysics Data System (ADS)

Koledina, K. F.; Gubaidullin, I. M.

2016-05-01

The complex reaction mechanism of α-olefin catalytic hydroalumination by alkylalanes is investigated via mathematical modeling that involves plotting the kinetic models for the individual reactions that make up a complex system and a separate study of their principles. Kinetic parameters of olefin catalytic hydroalumination are estimated. Activation energies of the possible steps of the schemes of complex reaction mechanisms are compared and possible reaction pathways are determined.

Sustainability and Resilience in the Urban Environment

EPA Science Inventory

Urban systems are formed by a diversity of actors and activities, and consist of complex interactions involving financial, information, energy, ecological, and material stocks and flows that operate on different spatial and temporal scales. The urban systems that emerge from thes...

Discovering Steiner Triple Systems through Problem Solving

ERIC Educational Resources Information Center

Sriraman, Bharath

2004-01-01

An attempt to implement problem solving as a teacher of ninth grade algebra is described. The problems selected were not general ones, they involved combinations and represented various situations and were more complex which lead to the discovery of Steiner triple systems.

Further Understanding of Complex Information Processing in Verbal Adolescents and Adults with Autism Spectrum Disorders

ERIC Educational Resources Information Center

Williams, Diane L.; Minshew, Nancy J.; Goldstein, Gerald

2015-01-01

More than 20?years ago, Minshew and colleagues proposed the Complex Information Processing model of autism in which the impairment is characterized as a generalized deficit involving multiple modalities and cognitive domains that depend on distributed cortical systems responsible for higher order abilities. Subsequent behavioral work revealed a…

The Effects of Goal-Contingent Payment on the Performance of a Complex Task.

ERIC Educational Resources Information Center

Campbell, Donald J.

1984-01-01

Using a complex, computerized decision-making task, 56 university students participated in a six-week, repeated measures, goal-setting project, involving different payment systems. Results indicated that goal-contingent payment is superior to hourly payment in influencing performance, even though the perceived valence of payment and the actual…

Using Simple Manipulatives to Improve Student Comprehension of a Complex Biological Process: Protein Synthesis

ERIC Educational Resources Information Center

Guzman, Karen; Bartlett, John

2012-01-01

Biological systems and living processes involve a complex interplay of biochemicals and macromolecular structures that can be challenging for undergraduate students to comprehend and, thus, misconceptions abound. Protein synthesis, or translation, is an example of a biological process for which students often hold many misconceptions. This article…

Complement Activation in Inflammatory Skin Diseases

PubMed Central

Giang, Jenny; Seelen, Marc A. J.; van Doorn, Martijn B. A.; Rissmann, Robert; Prens, Errol P.; Damman, Jeffrey

2018-01-01

The complement system is a fundamental part of the innate immune system, playing a crucial role in host defense against various pathogens, such as bacteria, viruses, and fungi. Activation of complement results in production of several molecules mediating chemotaxis, opsonization, and mast cell degranulation, which can contribute to the elimination of pathogenic organisms and inflammation. Furthermore, the complement system also has regulating properties in inflammatory and immune responses. Complement activity in diseases is rather complex and may involve both aberrant expression of complement and genetic deficiencies of complement components or regulators. The skin represents an active immune organ with complex interactions between cellular components and various mediators. Complement involvement has been associated with several skin diseases, such as psoriasis, lupus erythematosus, cutaneous vasculitis, urticaria, and bullous dermatoses. Several triggers including auto-antibodies and micro-organisms can activate complement, while on the other hand complement deficiencies can contribute to impaired immune complex clearance, leading to disease. This review provides an overview of the role of complement in inflammatory skin diseases and discusses complement factors as potential new targets for therapeutic intervention. PMID:29713318

SEU System Analysis: Not Just the Sum of All Parts

NASA Technical Reports Server (NTRS)

Berg, Melanie D.; Label, Kenneth

2014-01-01

Single event upset (SEU) analysis of complex systems is challenging. Currently, system SEU analysis is performed by component level partitioning and then either: the most dominant SEU cross-sections (SEUs) are used in system error rate calculations; or the partition SEUs are summed to eventually obtain a system error rate. In many cases, system error rates are overestimated because these methods generally overlook system level derating factors. The problem with overestimating is that it can cause overdesign and consequently negatively affect the following: cost, schedule, functionality, and validation/verification. The scope of this presentation is to discuss the risks involved with our current scheme of SEU analysis for complex systems; and to provide alternative methods for improvement.

Finite burn maneuver modeling for a generalized spacecraft trajectory design and optimization system.

PubMed

Ocampo, Cesar

2004-05-01

The modeling, design, and optimization of finite burn maneuvers for a generalized trajectory design and optimization system is presented. A generalized trajectory design and optimization system is a system that uses a single unified framework that facilitates the modeling and optimization of complex spacecraft trajectories that may operate in complex gravitational force fields, use multiple propulsion systems, and involve multiple spacecraft. The modeling and optimization issues associated with the use of controlled engine burn maneuvers of finite thrust magnitude and duration are presented in the context of designing and optimizing a wide class of finite thrust trajectories. Optimal control theory is used examine the optimization of these maneuvers in arbitrary force fields that are generally position, velocity, mass, and are time dependent. The associated numerical methods used to obtain these solutions involve either, the solution to a system of nonlinear equations, an explicit parameter optimization method, or a hybrid parameter optimization that combines certain aspects of both. The theoretical and numerical methods presented here have been implemented in copernicus, a prototype trajectory design and optimization system under development at the University of Texas at Austin.

Employee Participation Programs: Considerations for the School Site. Studies in Collective Bargaining.

ERIC Educational Resources Information Center

National Education Association, Washington, DC. Research Div.

Site-based decisionmaking programs offer important opportunities for school systems; however, the risks involved are significant and the decision to embrace the concept at the local level is a highly complex one. With site-based decisionmaking programs, teachers are directly involved in making decisions that affect the whole school, not merely…

Divorce and Special Education. PHP-c103

ERIC Educational Resources Information Center

PACER Center, 2004

2004-01-01

Every year the parents of a million American children are newly divorced. While divorce is difficult for all parties involved, children are often the most affected. If the children have disabilities and are involved with the special education system, the situation can be even more complex. The information in this document may help parents think…

Cx-02 Program, workshop on modeling complex systems

USGS Publications Warehouse

Mossotti, Victor G.; Barragan, Jo Ann; Westergard, Todd D.

2003-01-01

This publication contains the abstracts and program for the workshop on complex systems that was held on November 19-21, 2002, in Reno, Nevada. Complex systems are ubiquitous within the realm of the earth sciences. Geological systems consist of a multiplicity of linked components with nested feedback loops; the dynamics of these systems are non-linear, iterative, multi-scale, and operate far from equilibrium. That notwithstanding, It appears that, with the exception of papers on seismic studies, geology and geophysics work has been disproportionally underrepresented at regional and national meetings on complex systems relative to papers in the life sciences. This is somewhat puzzling because geologists and geophysicists are, in many ways, preadapted to thinking of complex system mechanisms. Geologists and geophysicists think about processes involving large volumes of rock below the sunlit surface of Earth, the accumulated consequence of processes extending hundreds of millions of years in the past. Not only do geologists think in the abstract by virtue of the vast time spans, most of the evidence is out-of-sight. A primary goal of this workshop is to begin to bridge the gap between the Earth sciences and life sciences through demonstration of the universality of complex systems science, both philosophically and in model structures.

Multi-Modal Traveler Information System - Performance Criteria for Evaluating GCM Corridor Strategies & Technologies

DOT National Transportation Integrated Search

1997-07-16

The Gary-Chicago-Milwaukee (GCM) Multi-Modal Traveler Information System (MMTIS) is a complex project involving a wide spectrum of participants. In order to facilitate its implementation it is important to understand the direction of the MMTIS. This ...

Crucial HSP70 co–chaperone complex unlocks metazoan protein disaggregation

PubMed Central

Nillegoda, Nadinath B.; Kirstein, Janine; Szlachcic, Anna; Berynskyy, Mykhaylo; Stank, Antonia; Stengel, Florian; Arnsburg, Kristin; Gao, Xuechao; Scior, Annika; Aebersold, Ruedi; Guilbride, D. Lys; Wade, Rebecca C.; Morimoto, Richard I.; Mayer, Matthias P.; Bukau, Bernd

2016-01-01

Protein aggregates are the hallmark of stressed and ageing cells, and characterize several pathophysiological states1,2. Healthy metazoan cells effectively eliminate intracellular protein aggregates3,4, indicating that efficient disaggregation and/or degradation mechanisms exist. However, metazoans lack the key heat-shock protein disaggregase HSP100 of non-metazoan HSP70-dependent protein disaggregation systems5,6, and the human HSP70 system alone, even with the crucial HSP110 nucleotide exchange factor, has poor disaggregation activity in vitro4,7. This unresolved conundrum is central to protein quality control biology. Here we show that synergic cooperation between complexed J-protein co-chaperones of classes A and B unleashes highly efficient protein disaggregation activity in human and nematode HSP70 systems. Metazoan mixed-class J-protein complexes are transient, involve complementary charged regions conserved in the J-domains and carboxy-terminal domains of each J-protein class, and are flexible with respect to subunit composition. Complex formation allows J-proteins to initiate transient higher order chaperone structures involving HSP70 and interacting nucleotide exchange factors. A network of cooperative class A and B J-protein interactions therefore provides the metazoan HSP70 machinery with powerful, flexible, and finely regulatable disaggregase activity and a further level of regulation crucial for cellular protein quality control. PMID:26245380

Communication challenges in complex medical environments.

PubMed

Lee, Jessica D; Hohler, Anna

2014-06-01

The provision of health care is becoming increasingly complex and can involve multiple providers and care setting transitions, particularly as the population is living longer, and often with chronic disease. The Electronic Health Record (EHR) was intended to provide a comprehensive documentation of a patient's health-related information; however, health care systems often function in isolation with EHRs that are unique only to that system. The EHR may also limit face-to-face communication between treating physicians within the same system. It is only with diligent effort that changes in medical management plans are conveyed among providers. When multiple providers are involved in a patient's care, physician-to-patient communication may also suffer, which can impact patient satisfaction and outcome. This article describes a scenario in which several lapses in communication occurred, and it outlines other common pitfalls while providing possible solutions for improving communication across the health care spectrum.

Cardiac involvement in antiphospholipid syndrome associated with Sneddon syndrome: a challenging diagnosis.

PubMed

Faustino, Ana; Paiva, Luís; Morgadinho, Ana; Trigo, Emília; Botelho, Ana; Costa, Marco; Leitão-Marques, António

2014-02-01

Sneddon syndrome is a rare clinical entity characterized by the association of ischemic cerebrovascular disease and livedo reticularis. The authors report a case of stroke and myocardial infarction in a 39-year-old man with Sneddon syndrome and antiphospholipid syndrome who subsequently met some criteria for systemic lupus erythematosus, highlighting the complexity of cardiovascular involvement in systemic diseases. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Cellular Decomposition Based Hybrid-Hierarchical Control Systems with Applications to Flight Management Systems

NASA Technical Reports Server (NTRS)

Caines, P. E.

1999-01-01

The work in this research project has been focused on the construction of a hierarchical hybrid control theory which is applicable to flight management systems. The motivation and underlying philosophical position for this work has been that the scale, inherent complexity and the large number of agents (aircraft) involved in an air traffic system imply that a hierarchical modelling and control methodology is required for its management and real time control. In the current work the complex discrete or continuous state space of a system with a small number of agents is aggregated in such a way that discrete (finite state machine or supervisory automaton) controlled dynamics are abstracted from the system's behaviour. High level control may then be either directly applied at this abstracted level, or, if this is in itself of significant complexity, further layers of abstractions may be created to produce a system with an acceptable degree of complexity at each level. By the nature of this construction, high level commands are necessarily realizable at lower levels in the system.

A two-state computational investigation of methane C--H and ethane C--C oxidative addition to [CpM(PH3)]n+ (M = Co, Rh, Ir; n = 0, 1).

PubMed

Petit, Alban; Richard, Philippe; Cacelli, Ivo; Poli, Rinaldo

2006-01-11

Reductive elimination of methane from methyl hydride half-sandwich phosphane complexes of the Group 9 metals has been investigated by DFT calculations on the model system [CpM(PH(3))(CH(3))(H)] (M = Co, Rh, Ir). For each metal, the unsaturated product has a triplet ground state; thus, spin crossover occurs during the reaction. All relevant stationary points on the two potential energy surfaces (PES) and the minimum energy crossing point (MECP) were optimized. Spin crossover occurs very near the sigma-CH(4) complex local minimum for the Co system, whereas the heavier Rh and Ir systems remain in the singlet state until the CH(4) molecule is almost completely expelled from the metal coordination sphere. No local sigma-CH(4) minimum was found for the Ir system. The energetic profiles agree with the nonexistence of the Co(III) methyl hydride complex and with the greater thermal stability of the Ir complex relative to the Rh complex. Reductive elimination of methane from the related oxidized complexes [CpM(PH(3))(CH(3))(H)](+) (M = Rh, Ir) proceeds entirely on the spin doublet PES, because the 15-electron [CpM(PH(3))](+) products have a doublet ground state. This process is thermodynamically favored by about 25 kcal mol(-1) relative to the corresponding neutral system. It is essentially barrierless for the Rh system and has a relatively small barrier (ca. 7.5 kcal mol(-1)) for the Ir system. In both cases, the reaction involves a sigma-CH(4) intermediate. Reductive elimination of ethane from [CpM(PH(3))(CH(3))(2)](+) (M = Rh, Ir) shows a similar thermodynamic profile, but is kinetically quite different from methane elimination from [CpM(PH(3))(CH(3))(H)](+): the reductive elimination barrier is much greater and does not involve a sigma-complex intermediate. The large difference in the calculated activation barriers (ca. 12.0 and ca. 30.5 kcal mol(-1) for the Rh and Ir systems, respectively) agrees with the experimental observation, for related systems, of oxidatively induced ethane elimination when M = Rh, whereas the related Ir systems prefer to decompose by alternative pathways.

Systems thinking, complexity and managerial decision-making: an analytical review.

PubMed

Cramp, D G; Carson, E R

2009-05-01

One feature that characterizes the organization and delivery of health care is its inherent complexity. All too often, with so much information and so many activities involved, it is difficult for decision-makers to determine in an objective fashion an appropriate course of action. It would appear that a holistic rather than a reductionist approach would be advantageous. The aim of this paper is to review how formal systems thinking can aid decision-making in complex situations. Consideration is given as to how the use of a number of systems modelling methodologies can help in gaining an understanding of a complex decision situation. This in turn can enhance the possibility of a decision being made in a more rational, explicit and transparent fashion. The arguments and approaches are illustrated using examples taken from the public health arena.

Magnetic interactions and magnetic anisotropy in exchange coupled 4f-3d systems: a case study of a heterodinuclear Ce3+-Fe3+ cyanide-bridged complex.

PubMed

Sorace, Lorenzo; Sangregorio, Claudio; Figuerola, Albert; Benelli, Cristiano; Gatteschi, Dante

2009-01-01

We report here a detailed single-crystal EPR and magnetic study of a homologous series of complexes of the type Ln-M (Ln = La(III), Ce(III); M = Fe(III), Co(III)). We were able to obtain a detailed picture of the low-lying levels of Ce(III) and Fe(III) centres through the combined use of single-crystal EPR and magnetic susceptibility data. We show that classical ligand field theory can be of great help in rationalising the energies of the low-lying levels of both the transition-metal and rare-earth ions. The combined analysis of single-crystal EPR and magnetic data of the coupled system Ce-Fe confirmed the great complexity of the interactions involving rare-earth elements. With little uncertainty, it turned out clearly that the description of the interaction involving the lowest lying spin levels requires the introduction of the isotropic, anisotropic and antisymmetric terms.

Flipping the NF-κB Switch in Macrophages | Center for Cancer Research

Cancer.gov

A critical component of the innate immune system, macrophages respond to diverse microbes by recognizing certain molecular patterns, such as the Gram-negative bacteria product lipopolysaccharide (LPS), via Toll-like receptors. Receptor activation stimulates a complex signaling network that involves, among others, the NF-κB pathway. The complexity of this network has hampered

What Gene-Environment Interactions Can Tell Us about Social Competence in Typical and Atypical Populations

ERIC Educational Resources Information Center

Iarocci, Grace; Yager, Jodi; Elfers, Theo

2007-01-01

Social competence is a complex human behaviour that is likely to involve a system of genes that interacts with a myriad of environmental risk and protective factors. The search for its genetic and environmental origins and influences is equally complex and will require a multidimensional conceptualization and multiple methods and levels of…

Highly Manufacturable Deep (Sub-Millimeter) Etching Enabled High Aspect Ratio Complex Geometry Lego-Like Silicon Electronics.

PubMed

Ghoneim, Mohamed Tarek; Hussain, Muhammad Mustafa

2017-04-01

A highly manufacturable deep reactive ion etching based process involving a hybrid soft/hard mask process technology shows high aspect ratio complex geometry Lego-like silicon electronics formation enabling free-form (physically flexible, stretchable, and reconfigurable) electronic systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Network representations of immune system complexity

PubMed Central

Subramanian, Naeha; Torabi-Parizi, Parizad; Gottschalk, Rachel A.; Germain, Ronald N.; Dutta, Bhaskar

2015-01-01

The mammalian immune system is a dynamic multi-scale system composed of a hierarchically organized set of molecular, cellular and organismal networks that act in concert to promote effective host defense. These networks range from those involving gene regulatory and protein-protein interactions underlying intracellular signaling pathways and single cell responses to increasingly complex networks of in vivo cellular interaction, positioning and migration that determine the overall immune response of an organism. Immunity is thus not the product of simple signaling events but rather non-linear behaviors arising from dynamic, feedback-regulated interactions among many components. One of the major goals of systems immunology is to quantitatively measure these complex multi-scale spatial and temporal interactions, permitting development of computational models that can be used to predict responses to perturbation. Recent technological advances permit collection of comprehensive datasets at multiple molecular and cellular levels while advances in network biology support representation of the relationships of components at each level as physical or functional interaction networks. The latter facilitate effective visualization of patterns and recognition of emergent properties arising from the many interactions of genes, molecules, and cells of the immune system. We illustrate the power of integrating ‘omics’ and network modeling approaches for unbiased reconstruction of signaling and transcriptional networks with a focus on applications involving the innate immune system. We further discuss future possibilities for reconstruction of increasingly complex cellular and organism-level networks and development of sophisticated computational tools for prediction of emergent immune behavior arising from the concerted action of these networks. PMID:25625853

23 CFR 971.212 - Federal lands safety management system (SMS).

Code of Federal Regulations, 2011 CFR

2011-04-01

.... (b) The SMS may be based on the guidance in “Safety Management Systems: Good Practices for Development and Implementation.”3 3 “Safety Management Systems: Good Practices for Development and... various levels of complexity depending on the nature of the facility and/or network involved. (e) The SMS...

23 CFR 971.212 - Federal lands safety management system (SMS).

Code of Federal Regulations, 2013 CFR

2013-04-01

.... (b) The SMS may be based on the guidance in “Safety Management Systems: Good Practices for Development and Implementation.”3 3 “Safety Management Systems: Good Practices for Development and... various levels of complexity depending on the nature of the facility and/or network involved. (e) The SMS...

23 CFR 971.212 - Federal lands safety management system (SMS).

Code of Federal Regulations, 2010 CFR

2010-04-01

.... (b) The SMS may be based on the guidance in “Safety Management Systems: Good Practices for Development and Implementation.”3 3 “Safety Management Systems: Good Practices for Development and... various levels of complexity depending on the nature of the facility and/or network involved. (e) The SMS...

23 CFR 971.212 - Federal lands safety management system (SMS).

Code of Federal Regulations, 2012 CFR

2012-04-01

.... (b) The SMS may be based on the guidance in “Safety Management Systems: Good Practices for Development and Implementation.”3 3 “Safety Management Systems: Good Practices for Development and... various levels of complexity depending on the nature of the facility and/or network involved. (e) The SMS...

23 CFR 971.212 - Federal lands safety management system (SMS).

Code of Federal Regulations, 2014 CFR

2014-04-01

.... (b) The SMS may be based on the guidance in “Safety Management Systems: Good Practices for Development and Implementation.”3 3 “Safety Management Systems: Good Practices for Development and... various levels of complexity depending on the nature of the facility and/or network involved. (e) The SMS...

Design and Development of a Web-Based Interactive Software Tool for Teaching Operating Systems

ERIC Educational Resources Information Center

Garmpis, Aristogiannis

2011-01-01

Operating Systems (OS) is an important and mandatory discipline in many Computer Science, Information Systems and Computer Engineering curricula. Some of its topics require a careful and detailed explanation from the instructor as they often involve theoretical concepts and somewhat complex mechanisms, demanding a certain degree of abstraction…

Structural study of complexes formed by acidic and neutral organophosphorus reagents

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

Braatz, Alexander D.; Antonio, Mark R.; Nilsson, Mikael

The coordination of the trivalent 4f ions, Ln = La 3+, Dy 3+, and Lu 3+, with neutral and acidic organophosphorus reagents, both individually and combined, was studied by use of X-ray absorption spectroscopy. These studies provide metrical information about the interatomic interactions between these cations and the ligands tri- n-butyl phosphate (TBP) and di- n-butyl phosphoric acid (HDBP), whose behavior are of practical importance to chemical separation processes that are currently used on an industrial scale. Previous studies have suggested the existence of complexes involving a mixture of ligands, accounting for extraction synergy. Through systematic variation of the aqueousmore » phase acidity and extractant concentration and combination, we have found that complexes with Ln and TBP : HDBP at any mixture and HDBP alone involve direct Ln–O interactions involving 6 oxygen atoms and distant Ln–P interactions involving on average 3–5 phosphorus atoms per Ln ion. It was also found that Ln complexes formed by TBP alone seem to favor eight oxygen coordination, though we were unable to obtain metrical results regarding the distant Ln–P interactions due to the low signal attributed to a lower concentration of Ln ions in the organic phases. Our study does not support the existence of mixed Ln–TBP–HDBP complexes but, rather, indicates that the lanthanides are extracted as either Ln–HDBP complexes or Ln–TBP complexes and that these complexes exist in different ratios depending on the conditions of the extraction system. Furthermore, this fundamental structural information offers insight into the solvent extraction processes that are taking place and are of particular importance to issues arising from the separation and disposal of radioactive materials from used nuclear fuel.« less

Structural study of complexes formed by acidic and neutral organophosphorus reagents

DOE PAGES

Braatz, Alexander D.; Antonio, Mark R.; Nilsson, Mikael

2016-12-23

The coordination of the trivalent 4f ions, Ln = La 3+, Dy 3+, and Lu 3+, with neutral and acidic organophosphorus reagents, both individually and combined, was studied by use of X-ray absorption spectroscopy. These studies provide metrical information about the interatomic interactions between these cations and the ligands tri- n-butyl phosphate (TBP) and di- n-butyl phosphoric acid (HDBP), whose behavior are of practical importance to chemical separation processes that are currently used on an industrial scale. Previous studies have suggested the existence of complexes involving a mixture of ligands, accounting for extraction synergy. Through systematic variation of the aqueousmore » phase acidity and extractant concentration and combination, we have found that complexes with Ln and TBP : HDBP at any mixture and HDBP alone involve direct Ln–O interactions involving 6 oxygen atoms and distant Ln–P interactions involving on average 3–5 phosphorus atoms per Ln ion. It was also found that Ln complexes formed by TBP alone seem to favor eight oxygen coordination, though we were unable to obtain metrical results regarding the distant Ln–P interactions due to the low signal attributed to a lower concentration of Ln ions in the organic phases. Our study does not support the existence of mixed Ln–TBP–HDBP complexes but, rather, indicates that the lanthanides are extracted as either Ln–HDBP complexes or Ln–TBP complexes and that these complexes exist in different ratios depending on the conditions of the extraction system. Furthermore, this fundamental structural information offers insight into the solvent extraction processes that are taking place and are of particular importance to issues arising from the separation and disposal of radioactive materials from used nuclear fuel.« less

Ionic Effects on Supercritical CO2-Brine Interfacial Tensions: Molecular Dynamics Simulations and a Universal Correlation with Ionic Strength, Temperature, and Pressure.

PubMed

Zhao, Lingling; Ji, Jiayuan; Tao, Lu; Lin, Shangchao

2016-09-13

For geological CO2 storage in deep saline aquifers, the interfacial tension (IFT) between supercritical CO2 and brine is critical for the storage security and design of the storage capacitance. However, currently, no predictive model exists to determine the IFT of supercritical CO2 against complex electrolyte solutions involving various mixed salt species at different concentrations and compositions. In this paper, we use molecular dynamics (MD) simulations to investigate the effect of salt ions on the incremental IFT at the supercritical CO2-brine interface with respect to that at the reference supercritical CO2-water interface. Supercritical CO2-NaCl solution, CO2-CaCl2 solution and CO2-(NaCl+CaCl2) mixed solution systems are simulated at 343 K and 20 MPa under different salinities and salt compositions. We find that the valence of the cations is the primary contributor to the variation in IFT, while the Lennard-Jones potentials for the cations pose a smaller impact on the IFT. Interestingly, the incremental IFT exhibits a general linear correlation with the ionic strength in the above three electrolyte systems, and the slopes are almost identical and independent of the solution types. Based on this finding, a universal predictive formula for IFTs of CO2-complex electrolyte solution systems is established, as a function of ionic strength, temperature, and pressure. The predicted IFTs using the established formula agree perfectly (with a high statistical confidence level of ∼96%) with a wide range of experimental data for CO2 interfacing with different electrolyte solutions, such as those involving MgCl2 and Na2SO4. This work provides an efficient and accurate route to directly predict IFTs in supercritical CO2-complex electrolyte solution systems for practical engineering applications, such as geological CO2 sequestration in deep saline aquifers and other interfacial systems involving complex electrolyte solutions.

Reduction of Subjective and Objective System Complexity

NASA Technical Reports Server (NTRS)

Watson, Michael D.

2015-01-01

Occam's razor is often used in science to define the minimum criteria to establish a physical or philosophical idea or relationship. Albert Einstein is attributed the saying "everything should be made as simple as possible, but not simpler". These heuristic ideas are based on a belief that there is a minimum state or set of states for a given system or phenomena. In looking at system complexity, these heuristics point us to an idea that complexity can be reduced to a minimum. How then, do we approach a reduction in complexity? Complexity has been described as a subjective concept and an objective measure of a system. Subjective complexity is based on human cognitive comprehension of the functions and inter relationships of a system. Subjective complexity is defined by the ability to fully comprehend the system. Simplifying complexity, in a subjective sense, is thus gaining a deeper understanding of the system. As Apple's Jonathon Ive has stated," It's not just minimalism or the absence of clutter. It involves digging through the depth of complexity. To be truly simple, you have to go really deep". Simplicity is not the absence of complexity but a deeper understanding of complexity. Subjective complexity, based on this human comprehension, cannot then be discerned from the sociological concept of ignorance. The inability to comprehend a system can be either a lack of knowledge, an inability to understand the intricacies of a system, or both. Reduction in this sense is based purely on a cognitive ability to understand the system and no system then may be truly complex. From this view, education and experience seem to be the keys to reduction or eliminating complexity. Objective complexity, is the measure of the systems functions and interrelationships which exist independent of human comprehension. Jonathon Ive's statement does not say that complexity is removed, only that the complexity is understood. From this standpoint, reduction of complexity can be approached in finding the optimal or 'best balance' of the system functions and interrelationships. This is achievable following von Bertalanffy's approach of describing systems as a set of equations representing both the system functions and the system interrelationships. Reduction is found based on an objective function defining the system output given variations in the system inputs and the system operating environment. By minimizing the objective function with respect to these inputs and environments, a reduced system can be found. Thus, a reduction of the system complexity is feasible.

Multi-Enzyme Complexes in the Thermophilic Archaea: The Effects of Temperature on Stability, Catalysis and Enzyme Interactions in a Multi-Component System

DTIC Science & Technology

2012-01-01

COVERED (From - To) 4. TITLE AND SUBTITLE Multi- enzyme complexes in the thermophilic archaea: The effects of temperature on stability, catalysis and... enzyme interactions in a multi- component system 5a. CONTRACT NUMBER 5b. GRANT NUMBER FA9550-07-1-0058 5c. PROGRAM ELEMENT NUMBER 61102F 6...involves cloning of the genes for the relevant lipoylation enzymes , and characterisation of the protein products 15. SUBJECT TERMS 16. SECURITY

Complexity in Soil Systems: What Does It Mean and How Should We Proceed?

NASA Astrophysics Data System (ADS)

Faybishenko, B.; Molz, F. J.; Brodie, E.; Hubbard, S. S.

2015-12-01

The complex soil systems approach is needed fundamentally for the development of integrated, interdisciplinary methods to measure and quantify the physical, chemical and biological processes taking place in soil, and to determine the role of fine-scale heterogeneities. This presentation is aimed at a review of the concepts and observations concerning complexity and complex systems theory, including terminology, emergent complexity and simplicity, self-organization and a general approach to the study of complex systems using the Weaver (1948) concept of "organized complexity." These concepts are used to provide understanding of complex soil systems, and to develop experimental and mathematical approaches to soil microbiological processes. The results of numerical simulations, observations and experiments are presented that indicate the presence of deterministic chaotic dynamics in soil microbial systems. So what are the implications for the scientists who wish to develop mathematical models in the area of organized complexity or to perform experiments to help clarify an aspect of an organized complex system? The modelers have to deal with coupled systems having at least three dependent variables, and they have to forgo making linear approximations to nonlinear phenomena. The analogous rule for experimentalists is that they need to perform experiments that involve measurement of at least three interacting entities (variables depending on time, space, and each other). These entities could be microbes in soil penetrated by roots. If a process being studied in a soil affects the soil properties, like biofilm formation, then this effect has to be measured and included. The mathematical implications of this viewpoint are examined, and results of numerical solutions to a system of equations demonstrating deterministic chaotic behavior are also discussed using time series and the 3D strange attractors.

Unraveling reaction pathways and specifying reaction kinetics for complex systems.

PubMed

Vinu, R; Broadbelt, Linda J

2012-01-01

Many natural and industrial processes involve a complex set of competing reactions that include several different species. Detailed kinetic modeling of such systems can shed light on the important pathways involved in various transformations and therefore can be used to optimize the process conditions for the desired product composition and properties. This review focuses on elucidating the various components involved in modeling the kinetics of pyrolysis and oxidation of polymers. The elementary free radical steps that constitute the chain reaction mechanism of gas-phase/nonpolar liquid-phase processes are outlined. Specification of the rate coefficients of the various reaction families, which is central to the theme of kinetics, is described. Construction of the reaction network on the basis of the types of end groups and reactive moieties in a polymer chain is discussed. Modeling frameworks based on the method of moments and kinetic Monte Carlo are evaluated using illustrations. Finally, the prospects and challenges in modeling biomass conversion are addressed.

Landscape change in the southern Piedmont: challenges, solutions, and uncertainty across scales

USGS Publications Warehouse

Conroy, M.J.; Allen, Craig R.; Peterson, J.T.; Pritchard, L.J.; Moore, C.T.

2003-01-01

The southern Piedmont of the southeastern United States epitomizes the complex and seemingly intractable problems and hard decisions that result from uncontrolled urban and suburban sprawl. Here we consider three recurrent themes in complicated problems involving complex systems: (1) scale dependencies and cross-scale, often nonlinear relationships; (2) resilience, in particular the potential for complex systems to move to alternate stable states with decreased ecological and/or economic value; and (3) uncertainty in the ability to understand and predict outcomes, perhaps particularly those that occur as a result of human impacts. We consider these issues in the context of landscape-level decision making, using as an example water resources and lotic systems in the Piedmont region of the southeastern United States.

Advancing the National and Global Knowledge Economy: The Role of Research Universities in Developing Countries

ERIC Educational Resources Information Center

Altbach, Philip G.

2013-01-01

Research universities are a central part of all academic systems. They are the key points of international contact and involvement. Research is produced, disseminated and in many cases imported. For developing countries, the mechanisms for the involvement of research universities in the global knowledge economy is complex, and includes issues of…

The Relationship between School Belonging, Sibling Aggression and Bullying Involvement: Implications for Students with and without Disabilities

ERIC Educational Resources Information Center

Rose, Chad A.; Simpson, Cynthia G.; Ellis, Stephanie K.

2016-01-01

Bullying is grounded in the interactions between an individual and complex social-ecological systems. Therefore, bullying involvement is not just confined to the classroom or school. Recent research suggests that sibling aggression may be a predictor for peer-level aggression. These findings may be more relevant for students with disabilities…

Global exponential periodicity and stability of discrete-time complex-valued recurrent neural networks with time-delays.

PubMed

Hu, Jin; Wang, Jun

2015-06-01

In recent years, complex-valued recurrent neural networks have been developed and analysed in-depth in view of that they have good modelling performance for some applications involving complex-valued elements. In implementing continuous-time dynamical systems for simulation or computational purposes, it is quite necessary to utilize a discrete-time model which is an analogue of the continuous-time system. In this paper, we analyse a discrete-time complex-valued recurrent neural network model and obtain the sufficient conditions on its global exponential periodicity and exponential stability. Simulation results of several numerical examples are delineated to illustrate the theoretical results and an application on associative memory is also given. Copyright © 2015 Elsevier Ltd. All rights reserved.

Quinonoid metal complexes: toward molecular switches.

PubMed

Dei, Andrea; Gatteschi, Dante; Sangregorio, Claudio; Sorace, Lorenzo

2004-11-01

The peculiar redox-active character of quinonoid metal complexes makes them extremely appealing to design materials of potential technological interest. We show here how the tuning of the properties of these systems can be pursued by using appropriate molecular synthetic techniques. In particular, we focus our attention on metal polyoxolene complexes exhibiting intramolecular electron transfer processes involving either the ligand and the metal ion or the two dioxolene moieties of a properly designed ligand thus inducing electronic bistability. The transition between the two metastable electronic states can be induced by different external stimuli such as temperature, pressure, light, or pH suggesting the use of these systems for molecular switches.

Caring for the Patient With Limited Systemic Scleroderma.

PubMed

Lachner, Kelly Denise

2016-01-01

Systemic scleroderma (systemic sclerosis) is a rare, autoimmune, collagen-vascular disease of unknown etiology that affects the connective tissues of the skin, internal organs, as well as the small blood vessels. There are 3 subclasses of systemic scleroderma: limited cutaneous, diffuse cutaneous, and sine scleroderma. Prognosis depends on the extent of organ involvement. Complications of systemic scleroderma can involve the cardiovascular, pulmonary, gastrointestinal, renal, integumentary, and the skeletal-muscular systems. Because systemic scleroderma is not common, many orthopaedic nurses may be unfamiliar with how to best provide care. This article provides information about the complexity of the different types of this disease and the basic nursing care of the patient with the most common subclass of systemic scleroderma, limited cutaneous systemic scleroderma.

Reaction Intermediates of Quinol Oxidation in a Photoactivatable System that Mimics Electron Transfer in the Cytochrome bc1 Complex

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

Cape, Jonathan L.; Bowman, Michael K.; Kramer, David M.

2005-03-30

Current competing models for the two-electron oxidation of quinol (QH{sub 2}) at the cytochrome bc{sub 1} complex and related complexes have different requirements for the reaction intermediate. At present, the intermediate species of the enzymatic oxidation process have not been observed or characterized, probably due to their transient nature. Here, we use a biomimetic oxidant, Ru(bpy){sub 2}(pbim)(PF6)2 (bpy = 2,2'-dipyridyl, pbim = 2-(2-benzimidazolate)pyridine) in an aprotic medium to probe the oxidation of the ubiquinol analogue, 2,3-dimethoxy-5-methyl-1,4-benzoquinol (UQH{sub 2}-0), an the plastoquinol analogue, trimethyl-1,4-benzoquinol (TMQH{sub 2}-0), using time-resolved and steady state spectroscopic techniques. This system qualitatively reproduces key features observed duringmore » ubiquinol oxidation by the mitochondrial cytochrome bc1 complex. Comparison of isotope dependent activation properties in the native and synthetic systems, as well as, analysis of the time-resolved direct-detection electron para magnetic resonance signals in the synthetic system allows us to conclude that: (1) the initial and rate-limiting step in quinol oxidation, both in the biological and biomimetic systems, involves electron and proton transfer, probably via a proton coupled electron transfer mechanism; (2) a neutral semiquinone intermediate is formed in the biomimetic system; and (3) oxidation of the QH*/QH{sub 2} couple for UQH{sub 2}-0, but not TMQH{sub 2}-0, exhibits a non-classical primary deuterium kinetic isotope effect on its Arrhenius activation energy ({Delta}G{sup TS}), where {Delta}G{sup TS} for the protiated form is larger than for the deuterated form. The same behavior is observed during steady state turnover of the cyt bc{sub 1} complex using ubiquinol, but not plastoquinol, as a substrate, leading to the conclusion that similar chemical pathways are involved in both systems. The synthetic system is an unambiguous n=1 electron acceptor and it is thus inferred that sequential oxidation of ubiquinol (by two sequential n=1 processes) is more rapid than a truly concerted (n=2) oxidation in the cyt bc{sub 1} complex.« less

Etoile Project : Social Intelligent ICT-System for very large scale education in complex systems

NASA Astrophysics Data System (ADS)

Bourgine, P.; Johnson, J.

2009-04-01

The project will devise new theory and implement new ICT-based methods of delivering high-quality low-cost postgraduate education to many thousands of people in a scalable way, with the cost of each extra student being negligible (< a few Euros). The research will create an in vivo laboratory of one to ten thousand postgraduate students studying courses in complex systems. This community is chosen because it is large and interdisciplinary and there is a known requirement for courses for thousand of students across Europe. The project involves every aspect of course production and delivery. Within this the research focused on the creation of a Socially Intelligent Resource Mining system to gather large volumes of high quality educational resources from the internet; new methods to deconstruct these to produce a semantically tagged Learning Object Database; a Living Course Ecology to support the creation and maintenance of evolving course materials; systems to deliver courses; and a ‘socially intelligent assessment system'. The system will be tested on one to ten thousand postgraduate students in Europe working towards the Complex System Society's title of European PhD in Complex Systems. Étoile will have a very high impact both scientifically and socially by (i) the provision of new scalable ICT-based methods for providing very low cost scientific education, (ii) the creation of new mathematical and statistical theory for the multiscale dynamics of complex systems, (iii) the provision of a working example of adaptation and emergence in complex socio-technical systems, and (iv) making a major educational contribution to European complex systems science and its applications.

Dynamic Buffer Capacity in Acid-Base Systems.

PubMed

Michałowska-Kaczmarczyk, Anna M; Michałowski, Tadeusz

The generalized concept of 'dynamic' buffer capacity β V is related to electrolytic systems of different complexity where acid-base equilibria are involved. The resulting formulas are presented in a uniform and consistent form. The detailed calculations are related to two Britton-Robinson buffers, taken as examples.

The conundrum of harmonizing resistance surveillance systems on a global level

USDA-ARS?s Scientific Manuscript database

Surveillance systems, particularly those involving complex data over time, provide unique challenges. They are as varied in design, intent, funding and function as the countries in which they exist. The Centers for Disease Control and Prevention define surveillance as ‘the ongoing systematic colle...

Nonlinear dynamical systems for theory and research in ergonomics.

PubMed

Guastello, Stephen J

2017-02-01

Nonlinear dynamical systems (NDS) theory offers new constructs, methods and explanations for phenomena that have in turn produced new paradigms of thinking within several disciplines of the behavioural sciences. This article explores the recent developments of NDS as a paradigm in ergonomics. The exposition includes its basic axioms, the primary constructs from elementary dynamics and so-called complexity theory, an overview of its methods, and growing areas of application within ergonomics. The applications considered here include: psychophysics, iconic displays, control theory, cognitive workload and fatigue, occupational accidents, resilience of systems, team coordination and synchronisation in systems. Although these applications make use of different subsets of NDS constructs, several of them share the general principles of the complex adaptive system. Practitioner Summary: Nonlinear dynamical systems theory reframes problems in ergonomics that involve complex systems as they change over time. The leading applications to date include psychophysics, control theory, cognitive workload and fatigue, biomechanics, occupational accidents, resilience of systems, team coordination and synchronisation of system components.

Automated and miniaturized detection of biological threats with a centrifugal microfluidic system

NASA Astrophysics Data System (ADS)

Mark, D.; van Oordt, T.; Strohmeier, O.; Roth, G.; Drexler, J.; Eberhard, M.; Niedrig, M.; Patel, P.; Zgaga-Griesz, A.; Bessler, W.; Weidmann, M.; Hufert, F.; Zengerle, R.; von Stetten, F.

2012-06-01

The world's growing mobility, mass tourism, and the threat of terrorism increase the risk of the fast spread of infectious microorganisms and toxins. Today's procedures for pathogen detection involve complex stationary devices, and are often too time consuming for a rapid and effective response. Therefore a robust and mobile diagnostic system is required. We present a microstructured LabDisk which performs complex biochemical analyses together with a mobile centrifugal microfluidic device which processes the LabDisk. This portable system will allow fully automated and rapid detection of biological threats at the point-of-need.

Oxidative mutagenesis of doxorubicin-Fe(III) complex.

PubMed

Kostoryz, E L; Yourtee, D M

2001-02-20

Doxorubicin has a high affinity for inorganic iron, Fe(III), and has potential to form doxorubicin-Fe(III) complexes in biological systems. Indirect involvement of iron has been substantiated in the oxidative mutagenicity of doxorubicin. In this study, however, direct involvement of Fe(III) was evaluated in mutagenicity studies with the doxorubicin-Fe(III) complex. The Salmonella mutagenicity assay with strain TA102 was used with a pre-incubation step. The highest mutagenicity of doxorubicin-Fe(III) complex was observed at the dose of 2.5nmol/plate of the complex. The S9-mix decreased this highest mutagenicity but increased the number of revertants at a higher dose of 10nmol/plate of the complex. On the other hand, the mutagenicity of the doxorubicin-Fe(III) complex at the doses of 0.25, 0.5, 1 and 2nmol/plate was enhanced about twice by the addition of glutathione plus H(2)O(2). This enhanced mutagenicity as well as of the complex itself, the complex plus glutathione, and the complex plus H(2)O(2) were reduced by the addition of ADR-529, an Fe(III) chelator, and potassium iodide, a hydroxyl radical scavenger. These results indicate that doxorubicin-Fe(III) complex exert the mutagenicity through oxidative DNA damage and that Fe(III) is a required element in the mutagenesis of doxorubicin.

Patterns of technical error among surgical malpractice claims: an analysis of strategies to prevent injury to surgical patients.

PubMed

Regenbogen, Scott E; Greenberg, Caprice C; Studdert, David M; Lipsitz, Stuart R; Zinner, Michael J; Gawande, Atul A

2007-11-01

To identify the most prevalent patterns of technical errors in surgery, and evaluate commonly recommended interventions in light of these patterns. The majority of surgical adverse events involve technical errors, but little is known about the nature and causes of these events. We examined characteristics of technical errors and common contributing factors among closed surgical malpractice claims. Surgeon reviewers analyzed 444 randomly sampled surgical malpractice claims from four liability insurers. Among 258 claims in which injuries due to error were detected, 52% (n = 133) involved technical errors. These technical errors were further analyzed with a structured review instrument designed by qualitative content analysis. Forty-nine percent of the technical errors caused permanent disability; an additional 16% resulted in death. Two-thirds (65%) of the technical errors were linked to manual error, 9% to errors in judgment, and 26% to both manual and judgment error. A minority of technical errors involved advanced procedures requiring special training ("index operations"; 16%), surgeons inexperienced with the task (14%), or poorly supervised residents (9%). The majority involved experienced surgeons (73%), and occurred in routine, rather than index, operations (84%). Patient-related complexities-including emergencies, difficult or unexpected anatomy, and previous surgery-contributed to 61% of technical errors, and technology or systems failures contributed to 21%. Most technical errors occur in routine operations with experienced surgeons, under conditions of increased patient complexity or systems failure. Commonly recommended interventions, including restricting high-complexity operations to experienced surgeons, additional training for inexperienced surgeons, and stricter supervision of trainees, are likely to address only a minority of technical errors. Surgical safety research should instead focus on improving decision-making and performance in routine operations for complex patients and circumstances.

Neuroprotective Effects and Mechanisms of Curcumin-Cu(II) and -Zn(II) Complexes Systems and Their Pharmacological Implications.

PubMed

Yan, Fa-Shun; Sun, Jian-Long; Xie, Wen-Hai; Shen, Liang; Ji, Hong-Fang

2017-12-28

Alzheimer's disease (AD) is the main form of dementia and has a steadily increasing prevalence. As both oxidative stress and metal homeostasis are involved in the pathogenesis of AD, it would be interesting to develop a dual function agent, targeting the two factors. Curcumin, a natural compound isolated from the rhizome of Curcuma longa , is an antioxidant and can also chelate metal ions. Whether the complexes of curcumin with metal ions possess neuroprotective effects has not been evaluated. Therefore, the present study was designed to investigate the protective effects of the complexes of curcumin with Cu(II) or Zn(II) on hydrogen peroxide (H₂O₂)-induced injury and the underlying molecular mechanisms. The use of rat pheochromocytoma (PC12) cells, a widely used neuronal cell model system, was adopted. It was revealed that curcumin-Cu(II) complexes systems possessed enhanced O₂ ·- -scavenging activities compared to unchelated curcumin. In comparison with unchelated curcumin, the protective effects of curcumin-Cu(II) complexes systems were stronger than curcumin-Zn(II) system. Curcumin-Cu(II) or -Zn(II) complexes systems significantly enhanced the superoxide dismutase, catalase, and glutathione peroxidase activities and attenuated the increase of malondialdehyde levels and caspase-3 and caspase-9 activities, in a dose-dependent manner. The curcumin-Cu(II) complex system with a 2:1 ratio exhibited the most significant effect. Further mechanistic study demonstrated that curcumin-Cu(II) or -Zn(II) complexes systems inhibited cell apoptosis via downregulating the nuclear factor κB (NF-κB) pathway and upregulating Bcl-2/Bax pathway. In summary, the present study found that curcumin-Cu(II) or -Zn(II) complexes systems, especially the former, possess significant neuroprotective effects, which indicates the potential advantage of curcumin as a promising agent against AD and deserves further study.

A plasmid-based reverse genetics system for influenza A virus.

PubMed Central

Pleschka, S; Jaskunas, R; Engelhardt, O G; Zürcher, T; Palese, P; García-Sastre, A

1996-01-01

A reverse genetics system for negative-strand RNA viruses was first successfully developed for influenza viruses. This technology involved the transfection of in vitro-reconstituted ribonucleoprotein (RNP) complexes into influenza virus-infected cells. We have now developed a method that allows intracellular reconstitution of RNP complexes from plasmid-based expression vectors. Expression of a viral RNA-like transcript is achieved from a plasmid containing a truncated human polymerase I (polI) promoter and a ribozyme sequence that generates the desired 3' end by autocatalytic cleavage. The polI-driven plasmid is cotransfected into human 293 cells with polII-responsive plasmids that express the viral PB1, PB2, PA, and NP proteins. This exclusively plasmid-driven system results in the efficient transcription and replication of the viral RNA-like reporter and allows the study of cis- and trans-acting signals involved in the transcription and replication of influenza virus RNAs. Using this system, we have also been able to rescue a synthetic neuraminidase gene into a recombinant influenza virus. This method represents a convenient alternative to the previously established RNP transfection system. PMID:8648766

Some aspects of mathematical and chemical modeling of complex chemical processes

NASA Technical Reports Server (NTRS)

Nemes, I.; Botar, L.; Danoczy, E.; Vidoczy, T.; Gal, D.

1983-01-01

Some theoretical questions involved in the mathematical modeling of the kinetics of complex chemical process are discussed. The analysis is carried out for the homogeneous oxidation of ethylbenzene in the liquid phase. Particular attention is given to the determination of the general characteristics of chemical systems from an analysis of mathematical models developed on the basis of linear algebra.

Photomagnetic Switching of the Complex [Nd(dmf)[subscript 4](H[subscript 2]O)[subscript 3]([mu]-CN)Fe(CN)[subscript 5

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

Svendsen, Helle; Overgaard, Jacob; Chevallier, Marie

2009-10-21

Single-crystal XRD experiments (see picture) reveal the excited-state structure of the photomagnetic heterobimetallic title complex. The system shows a decrease in all the iron-ligand bond lengths, suggesting that photoexcitation involves a ligand-to-metal charge transfer or a change in the superexchange coupling between the metal centers.

Structural changes at the metal ion binding site during the phosphoglucomutase reaction.

PubMed

Ray, W J; Post, C B; Liu, Y; Rhyu, G I

1993-01-12

An electron density map of the reactive, Cd2+ form of crystalline phosphoglucomutase from X-ray diffraction studies shows that the enzymic phosphate donates a nonbridging oxygen to the ligand sphere of the bound metal ion, which appears to be tetracoordinate. 31P and 113Cd NMR spectroscopy are used to assess changes in the properties of bound Cd2+ produced by substrate/product and by substrate/product analog inhibitors. The approximately 50 ppm downfield shift of the 113Cd resonance on formation of the complex of dephosphoenzyme and glucose 1,6-bisphosphate is associated with the initial sugar-phosphate binding step and likely involves a change in the geometry of the coordinating ligands. This interpretation is supported by spectral studies involving various complexes of the active Co2+ and Ni(2+)-enzyme. In addition, there is a loss of the 31P-113Cd J coupling that characterizes the monophosphate complexes of the Cd2+ enzyme either during or immediately after the PO3- transfer step that produces the bisphosphate complex, indicating a further change at the metal binding site. The implications of these observations with respect to the PO3- transfer process in the phosphoglucomutase reaction are considered. The apparent plasticity of the ligand sphere of the active site metal ion in this system may allow a single metal ion to act as a chaperone for a nonbridging oxygen during PO3- transfer or to allow a change in metal ion coordination during catalysis. A general NMR line shape/chemical-exchange analysis for evaluating binding in protein-ligand systems when exchange is intermediate to fast on the NMR time scale is described. Its application to the present system involves multiple exchange sites that depend on a single binding rate, thereby adding further constraints to the analysis.

Pleiotropic and Epistatic Network-Based Discovery: Integrated Networks for Target Gene Discovery

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

Weighill, Deborah; Jones, Piet; Shah, Manesh

Biological organisms are complex systems that are composed of functional networks of interacting molecules and macro-molecules. Complex phenotypes are the result of orchestrated, hierarchical, heterogeneous collections of expressed genomic variants. However, the effects of these variants are the result of historic selective pressure and current environmental and epigenetic signals, and, as such, their co-occurrence can be seen as genome-wide correlations in a number of different manners. Biomass recalcitrance (i.e., the resistance of plants to degradation or deconstruction, which ultimately enables access to a plant's sugars) is a complex polygenic phenotype of high importance to biofuels initiatives. This study makes usemore » of data derived from the re-sequenced genomes from over 800 different Populus trichocarpa genotypes in combination with metabolomic and pyMBMS data across this population, as well as co-expression and co-methylation networks in order to better understand the molecular interactions involved in recalcitrance, and identify target genes involved in lignin biosynthesis/degradation. A Lines Of Evidence (LOE) scoring system is developed to integrate the information in the different layers and quantify the number of lines of evidence linking genes to target functions. This new scoring system was applied to quantify the lines of evidence linking genes to lignin-related genes and phenotypes across the network layers, and allowed for the generation of new hypotheses surrounding potential new candidate genes involved in lignin biosynthesis in P. trichocarpa, including various AGAMOUS-LIKE genes. Lastly, the resulting Genome Wide Association Study networks, integrated with Single Nucleotide Polymorphism (SNP) correlation, co-methylation, and co-expression networks through the LOE scores are proving to be a powerful approach to determine the pleiotropic and epistatic relationships underlying cellular functions and, as such, the molecular basis for complex phenotypes, such as recalcitrance.« less

Pleiotropic and Epistatic Network-Based Discovery: Integrated Networks for Target Gene Discovery

DOE PAGES

Weighill, Deborah; Jones, Piet; Shah, Manesh; ...

2018-05-11

Biological organisms are complex systems that are composed of functional networks of interacting molecules and macro-molecules. Complex phenotypes are the result of orchestrated, hierarchical, heterogeneous collections of expressed genomic variants. However, the effects of these variants are the result of historic selective pressure and current environmental and epigenetic signals, and, as such, their co-occurrence can be seen as genome-wide correlations in a number of different manners. Biomass recalcitrance (i.e., the resistance of plants to degradation or deconstruction, which ultimately enables access to a plant's sugars) is a complex polygenic phenotype of high importance to biofuels initiatives. This study makes usemore » of data derived from the re-sequenced genomes from over 800 different Populus trichocarpa genotypes in combination with metabolomic and pyMBMS data across this population, as well as co-expression and co-methylation networks in order to better understand the molecular interactions involved in recalcitrance, and identify target genes involved in lignin biosynthesis/degradation. A Lines Of Evidence (LOE) scoring system is developed to integrate the information in the different layers and quantify the number of lines of evidence linking genes to target functions. This new scoring system was applied to quantify the lines of evidence linking genes to lignin-related genes and phenotypes across the network layers, and allowed for the generation of new hypotheses surrounding potential new candidate genes involved in lignin biosynthesis in P. trichocarpa, including various AGAMOUS-LIKE genes. Lastly, the resulting Genome Wide Association Study networks, integrated with Single Nucleotide Polymorphism (SNP) correlation, co-methylation, and co-expression networks through the LOE scores are proving to be a powerful approach to determine the pleiotropic and epistatic relationships underlying cellular functions and, as such, the molecular basis for complex phenotypes, such as recalcitrance.« less

The PLATO PPTK System: An Alternative Keyboard Using the PLATO Computer-Based Education System for the Orthopedically Handicapped.

ERIC Educational Resources Information Center

Goodman, William J.

Developed in response to the complex problems involved in providing equal educational opportunities for the intellectually alert orthopedically handicapped, the PLATO Programmable Terminal Keyset (PPTK) system makes the resources of PLATO compatible to the functional problems of a wide range of orthopedic conditions. This report describes the…

Application of Intelligent Tutoring Technology to an Apparently Mechanical Task.

ERIC Educational Resources Information Center

Newman, Denis

The increasing automation of many occupations leads to jobs that involve understanding and monitoring the operation of complex computer systems. One case is PATRIOT, an air defense surface-to-air missile system deployed by the U.S. Army. Radar information is processed and presented to the operators in highly abstract form. The system identifies…

Mapping fuels at multiple scales: landscape application of the fuel characteristic classification system.

Treesearch

D. McKenzie; C.L. Raymond; L.-K.B. Kellogg; R.A. Norheim; A.G. Andreu; A.C. Bayard; K.E. Kopper; E. Elman

2007-01-01

Fuel mapping is a complex and often multidisciplinary process, involving remote sensing, ground-based validation, statistical modeling, and knowledge-based systems. The scale and resolution of fuel mapping depend both on objectives and availability of spatial data layers. We demonstrate use of the Fuel Characteristic Classification System (FCCS) for fuel mapping at two...

Modeling of multiple equilibria in the self-aggregation of di-n-decyldimethylammonium chloride/octaethylene glycol monododecyl ether/cyclodextrin ternary systems.

PubMed

Leclercq, Loïc; Lubart, Quentin; Aubry, Jean-Marie; Nardello-Rataj, Véronique

2013-05-28

The surface tension equations of binary surfactant mixtures (di-n-decyldimethylammonium chloride and octaethylene glycol monododecyl ether) are established by combining the Szyszkowski equation of surfactant solutions, the ideal or nonideal mixing theory, and the phase separation model. For surfactant mixtures, the surface tension at the air-water interface is calculated using nonideal theory due to synergism between the two adsorbed surfactant types. The incorporation of cyclodextrin complexation model to the surface tension equations gives a robust model for the description of the surface tension isotherms of binary, ternary, and more complex systems involving numerous inclusion complexes. The surface tension data obtained experimentally shows excellent agreement with the theoretical model below and above the formation of micelles. The strong synergistic effect observed between the two surfactants is disrupted by the presence of CDs, leading to ideal behavior of ternary systems. Indeed, depending on the nature of the cyclodextrin (i.e., α, β, or γ), which allows a tuning of the cavity size, the binding constants with the surfactants are modified as well as the surface properties due to strong modification of equilibria involved in the ternary mixture.

Industrial application experiment series

NASA Technical Reports Server (NTRS)

Bluhm, S. A.

1980-01-01

The deployment of parabolic dish systems into the industrial sector for the purpose of providing users, suppliers, sponsors, and developers with a realistic assessment of system feasibility in selected near-term industrial applications will be accomplished initially through the industrial module experiment and later through additional experiments involving thermal, electric, and combined thermal and electrical systems. The approach is to progress through steps, from single module to multi-module systems, from thermal-only applications to more complex combined thermal and electric applications. The experience of other solar thermal experiments, particularly those involving parabolic dish hardware, will be utilized to the fullest extent possible in experiment planning and implementation.

A Research Framework for Understanding the Practical Impact of Family Involvement in the Juvenile Justice System: The Juvenile Justice Family Involvement Model.

PubMed

Walker, Sarah Cusworth; Bishop, Asia S; Pullmann, Michael D; Bauer, Grace

2015-12-01

Family involvement is recognized as a critical element of service planning for children's mental health, welfare and education. For the juvenile justice system, however, parents' roles in this system are complex due to youths' legal rights, public safety, a process which can legally position parents as plaintiffs, and a historical legacy of blaming parents for youth indiscretions. Three recent national surveys of juvenile justice-involved parents reveal that the current paradigm elicits feelings of stress, shame and distrust among parents and is likely leading to worse outcomes for youth, families and communities. While research on the impact of family involvement in the justice system is starting to emerge, the field currently has no organizing framework to guide a research agenda, interpret outcomes or translate findings for practitioners. We propose a research framework for family involvement that is informed by a comprehensive review and content analysis of current, published arguments for family involvement in juvenile justice along with a synthesis of family involvement efforts in other child-serving systems. In this model, family involvement is presented as an ascending, ordinal concept beginning with (1) exclusion, and moving toward climates characterized by (2) information-giving, (3) information-eliciting and (4) full, decision-making partnerships. Specific examples of how courts and facilities might align with these levels are described. Further, the model makes predictions for how involvement will impact outcomes at multiple levels with applications for other child-serving systems.

A new method for predicting response in complex linear systems. II. [under random or deterministic steady state excitation

NASA Technical Reports Server (NTRS)

Bogdanoff, J. L.; Kayser, K.; Krieger, W.

1977-01-01

The paper describes convergence and response studies in the low frequency range of complex systems, particularly with low values of damping of different distributions, and reports on the modification of the relaxation procedure required under these conditions. A new method is presented for response estimation in complex lumped parameter linear systems under random or deterministic steady state excitation. The essence of the method is the use of relaxation procedures with a suitable error function to find the estimated response; natural frequencies and normal modes are not computed. For a 45 degree of freedom system, and two relaxation procedures, convergence studies and frequency response estimates were performed. The low frequency studies are considered in the framework of earlier studies (Kayser and Bogdanoff, 1975) involving the mid to high frequency range.

High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides

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

Daniel A. Mosher; Xia Tang; Ronald J. Brown

2007-07-27

This final report describes the motivations, activities and results of the hydrogen storage independent project "High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides" performed by the United Technologies Research Center under the Department of Energy Hydrogen Program, contract # DE-FC36-02AL67610. The objectives of the project were to identify and address the key systems technologies associated with applying complex hydride materials, particularly ones which differ from those for conventional metal hydride based storage. This involved the design, fabrication and testing of two prototype systems based on the hydrogen storage material NaAlH4. Safety testing, catalysis studies, heat exchangermore » optimization, reaction kinetics modeling, thermochemical finite element analysis, powder densification development and material neutralization were elements included in the effort.« less

Prospects of engineering thermotolerance in crops through modulation of heat stress transcription factor and heat shock protein networks.

PubMed

Fragkostefanakis, Sotirios; Röth, Sascha; Schleiff, Enrico; Scharf, Klaus-Dieter

2015-09-01

Cell survival under high temperature conditions involves the activation of heat stress response (HSR), which in principle is highly conserved among different organisms, but shows remarkable complexity and unique features in plant systems. The transcriptional reprogramming at higher temperatures is controlled by the activity of the heat stress transcription factors (Hsfs). Hsfs allow the transcriptional activation of HSR genes, among which heat shock proteins (Hsps) are best characterized. Hsps belong to multigene families encoding for molecular chaperones involved in various processes including maintenance of protein homeostasis as a requisite for optimal development and survival under stress conditions. Hsfs form complex networks to activate downstream responses, but are concomitantly subjected to cell-type-dependent feedback regulation through factor-specific physical and functional interactions with chaperones belonging to Hsp90, Hsp70 and small Hsp families. There is increasing evidence that the originally assumed specialized function of Hsf/chaperone networks in the HSR turns out to be a complex central stress response system that is involved in the regulation of a broad variety of other stress responses and may also have substantial impact on various developmental processes. Understanding in detail the function of such regulatory networks is prerequisite for sustained improvement of thermotolerance in important agricultural crops. © 2014 John Wiley & Sons Ltd.

Life without complex I: proteome analyses of an Arabidopsis mutant lacking the mitochondrial NADH dehydrogenase complex

PubMed Central

Fromm, Steffanie; Senkler, Jennifer; Eubel, Holger; Peterhänsel, Christoph; Braun, Hans-Peter

2016-01-01

The mitochondrial NADH dehydrogenase complex (complex I) is of particular importance for the respiratory chain in mitochondria. It is the major electron entry site for the mitochondrial electron transport chain (mETC) and therefore of great significance for mitochondrial ATP generation. We recently described an Arabidopsis thaliana double-mutant lacking the genes encoding the carbonic anhydrases CA1 and CA2, which both form part of a plant-specific ‘carbonic anhydrase domain’ of mitochondrial complex I. The mutant lacks complex I completely. Here we report extended analyses for systematically characterizing the proteome of the ca1ca2 mutant. Using various proteomic tools, we show that lack of complex I causes reorganization of the cellular respiration system. Reduced electron entry into the respiratory chain at the first segment of the mETC leads to induction of complexes II and IV as well as alternative oxidase. Increased electron entry at later segments of the mETC requires an increase in oxidation of organic substrates. This is reflected by higher abundance of proteins involved in glycolysis, the tricarboxylic acid cycle and branched-chain amino acid catabolism. Proteins involved in the light reaction of photosynthesis, the Calvin cycle, tetrapyrrole biosynthesis, and photorespiration are clearly reduced, contributing to the significant delay in growth and development of the double-mutant. Finally, enzymes involved in defense against reactive oxygen species and stress symptoms are much induced. These together with previously reported insights into the function of plant complex I, which were obtained by analysing other complex I mutants, are integrated in order to comprehensively describe ‘life without complex I’. PMID:27122571

Adaptation of the Mitochondrial Genome in Cephalopods: Enhancing Proton Translocation Channels and the Subunit Interactions

PubMed Central

Almeida, Daniela; Maldonado, Emanuel; Vasconcelos, Vitor; Antunes, Agostinho

2015-01-01

Mitochondrial protein-coding genes (mt genes) encode subunits forming complexes of crucial cellular pathways, including those involved in the vital process of oxidative phosphorylation (OXPHOS). Despite the vital role of the mitochondrial genome (mt genome) in the survival of organisms, little is known with respect to its adaptive implications within marine invertebrates. The molluscan Class Cephalopoda is represented by a marine group of species known to occupy contrasting environments ranging from the intertidal to the deep sea, having distinct metabolic requirements, varied body shapes and highly advanced visual and nervous systems that make them highly competitive and successful worldwide predators. Thus, cephalopods are valuable models for testing natural selection acting on their mitochondrial subunits (mt subunits). Here, we used concatenated mt genes from 17 fully sequenced mt genomes of diverse cephalopod species to generate a robust mitochondrial phylogeny for the Class Cephalopoda. We followed an integrative approach considering several branches of interest–covering cephalopods with distinct morphologies, metabolic rates and habitats–to identify sites under positive selection and localize them in the respective protein alignment and/or tridimensional structure of the mt subunits. Our results revealed significant adaptive variation in several mt subunits involved in the energy production pathway of cephalopods: ND5 and ND6 from Complex I, CYTB from Complex III, COX2 and COX3 from Complex IV, and in ATP8 from Complex V. Furthermore, we identified relevant sites involved in protein-interactions, lining proton translocation channels, as well as disease/deficiencies related sites in the aforementioned complexes. A particular case, revealed by this study, is the involvement of some positively selected sites, found in Octopoda lineage in lining proton translocation channels (site 74 from ND5) and in interactions between subunits (site 507 from ND5) of Complex I. PMID:26285039

Emerging functions of multi-protein complex Mediator with special emphasis on plants.

PubMed

Malik, Naveen; Agarwal, Pinky; Tyagi, Akhilesh

2017-10-01

Mediator is a multi-subunit protein complex which is involved in transcriptional regulation in yeast and other eukaryotes. As a co-activator, it connects information from transcriptional activators/repressors to transcriptional machinery including RNA polymerase II and general transcription factors. It is not only involved in transcription initiation but also has important roles to play in transcription elongation and termination. Functional attributes of different Mediator subunits have been largely defined in yeast and mammalian systems earlier, while such studies in plants have gained momentum recently. Mediator regulates various processes related to plant development and is also involved in biotic and abiotic stress response. Thus, plant Mediator, like yeast and mammalian Mediator complex, is indispensable for plant growth and survival. Interaction of its multiple subunits with other regulatory proteins and their ectopic expression or knockdown in model plant like Arabidopsis and certain crop plants are paving the way to biochemical analysis and unravel molecular mechanisms of action of Mediator in plants.

Analysis of Pilot Feedback Regarding the Use of State Awareness Technologies During Complex Situations

NASA Technical Reports Server (NTRS)

Evans, Emory; Young, Steven D.; Daniels, Taumi; Santiago-Espada, Yamira; Etherington, Tim

2016-01-01

A flight simulation study was conducted at NASA Langley Research Center to evaluate flight deck systems that (1) predict aircraft energy state and/or autoflight configuration, (2) present the current state and expected future state of automated systems, and/or (3) show the state of flight-critical data systems in use by automated systems and primary flight instruments. Four new technology concepts were evaluated vis-à-vis current state-of-the-art flight deck systems and indicators. This human-in-the-loop study was conducted using commercial airline crews. Scenarios spanned a range of complex conditions and several emulated causal factors and complexity in recent accidents involving loss of state awareness by pilots (e.g. energy state, automation state, and/or system state). Data were collected via questionnaires administered after each flight, audio/video recordings, physiological data, head and eye tracking data, pilot control inputs, and researcher observations. This paper strictly focuses on findings derived from the questionnaire responses. It includes analysis of pilot subjective measures of complexity, decision making, workload, situation awareness, usability, and acceptability.

Parasites, ecosystems and sustainability: an ecological and complex systems perspective.

PubMed

Horwitz, Pierre; Wilcox, Bruce A

2005-06-01

Host-parasite relationships can be conceptualised either narrowly, where the parasite is metabolically dependent on the host, or more broadly, as suggested by an ecological-evolutionary and complex systems perspective. In this view Host-parasite relationships are part of a larger set of ecological and co-evolutionary interdependencies and a complex adaptive system. These interdependencies affect not just the hosts, vectors, parasites, the immediate agents, but also those indirectly or consequentially affected by the relationship. Host-parasite relationships also can be viewed as systems embedded within larger systems represented by ecological communities and ecosystems. So defined, it can be argued that Host-parasite relationships may often benefit their hosts and contribute significantly to the structuring of ecological communities. The broader, complex adaptive system view also contributes to understanding the phenomenon of disease emergence, the ecological and evolutionary mechanisms involved, and the role of parasitology in research and management of ecosystems in light of the apparently growing problem of emerging infectious diseases in wildlife and humans. An expanded set of principles for integrated parasite management is suggested by this perspective.

Sustainability: Why the Language and Ethics of Sustainability Matter in the Geoscience Classroom

ERIC Educational Resources Information Center

Metzger, Ellen P.; Curren, Randall R.

2017-01-01

Because challenges to sustainability arise at the intersection of human and biophysical systems they are inescapably embedded in social contexts and involve multiple stakeholders with diverse and often conflicting needs and value systems. Addressing complex and solution-resistant problems such as climate change, biodiversity loss, and…

Handwriting Difficulties in Children with Autism Spectrum Disorders: A Scoping Review

ERIC Educational Resources Information Center

Kushki, Azadeh; Chau, Tom; Anagnostou, Evdokia

2011-01-01

Functional handwriting involves complex interactions among physical, cognitive and sensory systems. Impairments in many aspects of these systems are associated with Autism spectrum disorders (ASD), suggesting a heightened risk of handwriting difficulties in children with ASD. This scoping review aimed to: (1) survey the existing evidence about…

Computer program determines chemical composition of physical system at equilibrium

NASA Technical Reports Server (NTRS)

Kwong, S. S.

1966-01-01

FORTRAN 4 digital computer program calculates equilibrium composition of complex, multiphase chemical systems. This is a free energy minimization method with solution of the problem reduced to mathematical operations, without concern for the chemistry involved. Also certain thermodynamic properties are determined as byproducts of the main calculations.

Evaluating the impacts of agricultural land management practices: A probabilistic hydrologic modeling approach

USDA-ARS?s Scientific Manuscript database

The complexity of the hydrologic system challenges the development of models. One issue faced during the model development stage is the uncertainty involved in model parameterization. Using a single optimized set of parameters (one snapshot) to represent baseline conditions of the system limits the ...

Ice Storage System for School Complex.

ERIC Educational Resources Information Center

Montgomery, Ross D.

1998-01-01

Describes a project at the Manatee Education Center in Naples, Florida, which won an ASHRAE award. Project involved the implementation of ice-storage technology in 19 schools. Compares the performance of ice-storage systems with traditional chiller designs in two other schools. Tables illustrate costs for the campuses. Addresses the maintenance…

Augmentative and Alternative Communication in the Early Childhood Years

ERIC Educational Resources Information Center

Hanline, Mary Frances; Nunes, Debora; Worthy, M. Brandy

2007-01-01

Augmentative and alternative communication (AAC) systems provide individuals unable to communicate effectively with speech a method of communicating. The choice and use of an AAC system is a complex and challenging process. It is best accomplished within a collaborative team model involving family members, child care providers and teachers,…

Subscriber Response System. Progress Report.

ERIC Educational Resources Information Center

Callais, Richard T.

Results of preliminary tests made prior and subsequent to the installation of a two-way interactive communication system which involves a computer complex termed the Local Processing Center and subscriber terminals located in the home or business location are reported. This first phase of the overall test plan includes tests made at Theta-Com…

Physical Models that Provide Guidance in Visualization Deconstruction in an Inorganic Context

ERIC Educational Resources Information Center

Schiltz, Holly K.; Oliver-Hoyo, Maria T.

2012-01-01

Three physical model systems have been developed to help students deconstruct the visualization needed when learning symmetry and group theory. The systems provide students with physical and visual frames of reference to facilitate the complex visualization involved in symmetry concepts. The permanent reflection plane demonstration presents an…

Atwood's Machine as a Tool to Introduce Variable Mass Systems

ERIC Educational Resources Information Center

de Sousa, Celia A.

2012-01-01

This article discusses an instructional strategy which explores eventual similarities and/or analogies between familiar problems and more sophisticated systems. In this context, the Atwood's machine problem is used to introduce students to more complex problems involving ropes and chains. The methodology proposed helps students to develop the…

24 CFR 103.205 - Systemic processing.

Code of Federal Regulations, 2010 CFR

2010-04-01

... are pervasive or institutional in nature, or that the processing of the complaint will involve complex issues, novel questions of fact or law, or will affect a large number of persons, the Assistant Secretary...

Everyone Wants One...A Slightly Different One: The Process of Introducing a User Interface System into an Online Public Access Catalog Network.

ERIC Educational Resources Information Center

Jenkins, Darrell L.

The development, testing, introduction, evaluation, and refinement of a user interface for a statewide, multi-library online public access catalog network can be a very involved and politically complex enterprise. A multitude of perspectives, assumptions, preferences, and needs accompanies the multitude of players involved, i.e., library…

[The endogenous opioid system and drug addiction].

PubMed

Maldonado, R

2010-01-01

Drug addiction is a chronic brain disorder leading to complex adaptive changes within the brain reward circuits. Several neurotransmitters, including the endogenous opioid system are involved in these changes. The opioid system plays a pivotal role in different aspects of addiction. Thus, opioid receptors and endogenous opioid peptides are largely distributed in the mesolimbic system and modulate dopaminergic activity within the reward circuits. Opioid receptors and peptides are selectively involved in several components of the addictive processes induced by opioids, cannabinoids, psychostimulants, alcohol and nicotine. This review is focused on the contribution of each component of the endogenous opioid system in the addictive properties of the different drugs of abuse. Copyright 2010 Elsevier Masson SAS. All rights reserved.

Behavioural and molecular endophenotypes in psychotic disorders reveal heritable abnormalities in glutamatergic neurotransmission

PubMed Central

Scoriels, L; Salek, R M; Goodby, E; Grainger, D; Dean, A M; West, J A; Griffin, J L; Suckling, J; Nathan, P J; Lennox, B R; Murray, G K; Bullmore, E T; Jones, P B

2015-01-01

Psychotic disorders such as schizophrenia are biologically complex and carry huge population morbidity due to their prevalence, persistence and associated disability. Defined by features such as delusions and hallucinations, they involve cognitive dysfunction and neurotransmitter dysregulations that appear mostly to involve the dopaminergic and glutamatergic systems. A number of genetic and environmental factors are associated with these disorders but it has been difficult to identify the biological pathways underlying the principal symptoms. The endophenotype concept of stable, heritable traits that form a mechanistic link between genes and an overt expression of the disorder has potential to reduce the complexity of psychiatric phenotypes. In this study, we used a genetically sensitive design with individuals with a first episode of psychosis, their non-affected first-degree relatives and non-related healthy controls. Metabolomic analysis was combined with neurocognitive assessment to identify multilevel endophenotypic patterns: one concerned reaction times during the performance of cognitive and emotional tests that have previously been associated with the glutamate neurotransmission system, the other involved metabolites involved directly and indirectly in the co-activation of the N-methyl-D-aspartate receptor, a major receptor of the glutamate system. These cognitive and metabolic endophenotypes may comprise a single construct, such that genetically mediated dysfunction in the glutamate system may be responsible for delays in response to cognitive and emotional functions in psychotic disorders. This focus on glutamatergic neurotransmission should guide drug discovery and experimental medicine programmes in schizophrenia and related disorders. PMID:25826115

The complexity of patient safety reporting systems in UK dentistry.

PubMed

Renton, T; Master, S

2016-10-21

Since the 'Francis Report', UK regulation focusing on patient safety has significantly changed. Healthcare workers are increasingly involved in NHS England patient safety initiatives aimed at improving reporting and learning from patient safety incidents (PSIs). Unfortunately, dentistry remains 'isolated' from these main events and continues to have a poor record for reporting and learning from PSIs and other events, thus limiting improvement of patient safety in dentistry. The reasons for this situation are complex.This paper provides a review of the complexities of the existing systems and procedures in relation to patient safety in dentistry. It highlights the conflicting advice which is available and which further complicates an overly burdensome process. Recommendations are made to address these problems with systems and procedures supporting patient safety development in dentistry.

Mathematical and Computational Modeling in Complex Biological Systems

PubMed Central

Li, Wenyang; Zhu, Xiaoliang

2017-01-01

The biological process and molecular functions involved in the cancer progression remain difficult to understand for biologists and clinical doctors. Recent developments in high-throughput technologies urge the systems biology to achieve more precise models for complex diseases. Computational and mathematical models are gradually being used to help us understand the omics data produced by high-throughput experimental techniques. The use of computational models in systems biology allows us to explore the pathogenesis of complex diseases, improve our understanding of the latent molecular mechanisms, and promote treatment strategy optimization and new drug discovery. Currently, it is urgent to bridge the gap between the developments of high-throughput technologies and systemic modeling of the biological process in cancer research. In this review, we firstly studied several typical mathematical modeling approaches of biological systems in different scales and deeply analyzed their characteristics, advantages, applications, and limitations. Next, three potential research directions in systems modeling were summarized. To conclude, this review provides an update of important solutions using computational modeling approaches in systems biology. PMID:28386558

Mathematical and Computational Modeling in Complex Biological Systems.

PubMed

Ji, Zhiwei; Yan, Ke; Li, Wenyang; Hu, Haigen; Zhu, Xiaoliang

2017-01-01

The biological process and molecular functions involved in the cancer progression remain difficult to understand for biologists and clinical doctors. Recent developments in high-throughput technologies urge the systems biology to achieve more precise models for complex diseases. Computational and mathematical models are gradually being used to help us understand the omics data produced by high-throughput experimental techniques. The use of computational models in systems biology allows us to explore the pathogenesis of complex diseases, improve our understanding of the latent molecular mechanisms, and promote treatment strategy optimization and new drug discovery. Currently, it is urgent to bridge the gap between the developments of high-throughput technologies and systemic modeling of the biological process in cancer research. In this review, we firstly studied several typical mathematical modeling approaches of biological systems in different scales and deeply analyzed their characteristics, advantages, applications, and limitations. Next, three potential research directions in systems modeling were summarized. To conclude, this review provides an update of important solutions using computational modeling approaches in systems biology.

The life of plant mitochondrial complex I.

PubMed

Braun, Hans-Peter; Binder, Stefan; Brennicke, Axel; Eubel, Holger; Fernie, Alisdair R; Finkemeier, Iris; Klodmann, Jennifer; König, Ann-Christine; Kühn, Kristina; Meyer, Etienne; Obata, Toshihiro; Schwarzländer, Markus; Takenaka, Mizuki; Zehrmann, Anja

2014-11-01

The mitochondrial NADH dehydrogenase complex (complex I) of the respiratory chain has several remarkable features in plants: (i) particularly many of its subunits are encoded by the mitochondrial genome, (ii) its mitochondrial transcripts undergo extensive maturation processes (e.g. RNA editing, trans-splicing), (iii) its assembly follows unique routes, (iv) it includes an additional functional domain which contains carbonic anhydrases and (v) it is, indirectly, involved in photosynthesis. Comprising about 50 distinct protein subunits, complex I of plants is very large. However, an even larger number of proteins are required to synthesize these subunits and assemble the enzyme complex. This review aims to follow the complete "life cycle" of plant complex I from various molecular perspectives. We provide arguments that complex I represents an ideal model system for studying the interplay of respiration and photosynthesis, the cooperation of mitochondria and the nucleus during organelle biogenesis and the evolution of the mitochondrial oxidative phosphorylation system. Copyright © 2014 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

A Three-Hybrid System to Probe In Vivo Protein-Protein Interactions: Application to the Essential Proteins of the RD1 Complex of M. tuberculosis

PubMed Central

Bhalla, Kuhulika; Ghosh, Anamika; Kumar, Krishan; Kumar, Sushil; Ranganathan, Anand

2011-01-01

Background Protein-protein interactions play a crucial role in enabling a pathogen to survive within a host. In many cases the interactions involve a complex of proteins rather than just two given proteins. This is especially true for pathogens like M. tuberculosis that are able to successfully survive the inhospitable environment of the macrophage. Studying such interactions in detail may help in developing small molecules that either disrupt or augment the interactions. Here, we describe the development of an E. coli based bacterial three-hybrid system that can be used effectively to study ternary protein complexes. Methodology/Principal Findings The protein-protein interactions involved in M. tuberculosis pathogenesis have been used as a model for the validation of the three-hybrid system. Using the M. tuberculosis RD1 encoded proteins CFP10, ESAT6 and Rv3871 for our proof-of-concept studies, we show that the interaction between the proteins CFP10 and Rv3871 is strengthened and stabilized in the presence of ESAT6, the known heterodimeric partner of CFP10. Isolating peptide candidates that can disrupt crucial protein-protein interactions is another application that the system offers. We demonstrate this by using CFP10 protein as a disruptor of a previously established interaction between ESAT6 and a small peptide HCL1; at the same time we also show that CFP10 is not able to disrupt the strong interaction between ESAT6 and another peptide SL3. Conclusions/Significance The validation of the three-hybrid system paves the way for finding new peptides that are stronger binders of ESAT6 compared even to its natural partner CFP10. Additionally, we believe that the system offers an opportunity to study tri-protein complexes and also perform a screening of protein/peptide binders to known interacting proteins so as to elucidate novel tri-protein complexes. PMID:22087330

Three-dimensional mapping in the electrophysiological laboratory.

PubMed

Maury, Philippe; Monteil, Benjamin; Marty, Lilian; Duparc, Alexandre; Mondoly, Pierre; Rollin, Anne

2018-06-07

Investigation and catheter ablation of cardiac arrhythmias are currently still based on optimal knowledge of arrhythmia mechanisms in relation to the cardiac anatomy involved, in order to target their crucial components. Currently, most complex arrhythmias are investigated using three-dimensional electroanatomical navigation systems, because these are felt to optimally integrate both the anatomical and electrophysiological features of a given arrhythmia in a given patient. In this article, we review the technical background of available three-dimensional electroanatomical navigation systems, and their potential use in complex ablations. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Chaos, complexity and complicatedness: lessons from rocket science.

PubMed

Norman, Geoff

2011-06-01

Recently several authors have drawn parallels between educational research and some theories of natural science, in particular complexity theory and chaos theory. The central claim is that both the natural science theories are useful metaphors for education research in that they deal with phenomena that involve many variables interacting in complex, non-linear and unstable ways, and leading to effects that are neither reproducible nor comprehensible. This paper presents a counter-argument. I begin by carefully examining the concepts of uncertainty, complexity and chaos, as described in physical science. I distinguish carefully between systems that are, respectively, complex, chaotic and complicated. I demonstrate that complex and chaotic systems have highly specific characteristics that are unlikely to be present in education systems. I then suggest that, in fact, there is ample evidence that human learning can be understood adequately with conventional linear models. The implications of these opposing world views are substantial. If education science has the properties of complex or chaotic systems, we should abandon any attempt at control or understanding. However, as I point out, to do so would ignore a number of recent developments in our understanding of learning that hold promise to yield substantial improvements in effectiveness and efficiency of learning. © Blackwell Publishing Ltd 2011.

Science information systems: Visualization

NASA Technical Reports Server (NTRS)

Wall, Ray J.

1991-01-01

Future programs in earth science, planetary science, and astrophysics will involve complex instruments that produce data at unprecedented rates and volumes. Current methods for data display, exploration, and discovery are inadequate. Visualization technology offers a means for the user to comprehend, explore, and examine complex data sets. The goal of this program is to increase the effectiveness and efficiency of scientists in extracting scientific information from large volumes of instrument data.

Enriched Environment Increases PCNA and PARP1 Levels in Octopus vulgaris Central Nervous System: First Evidence of Adult Neurogenesis in Lophotrochozoa.

PubMed

Bertapelle, Carla; Polese, Gianluca; Di Cosmo, Anna

2017-06-01

Organisms showing a complex and centralized nervous system, such as teleosts, amphibians, reptiles, birds and mammals, and among invertebrates, crustaceans and insects, can adjust their behavior according to the environmental challenges. Proliferation, differentiation, migration, and axonal and dendritic development of newborn neurons take place in brain areas where structural plasticity, involved in learning, memory, and sensory stimuli integration, occurs. Octopus vulgaris has a complex and centralized nervous system, located between the eyes, with a hierarchical organization. It is considered the most "intelligent" invertebrate for its advanced cognitive capabilities, as learning and memory, and its sophisticated behaviors. The experimental data obtained by immunohistochemistry and western blot assay using proliferating cell nuclear antigen and poli (ADP-ribose) polymerase 1 as marker of cell proliferation and synaptogenesis, respectively, reviled cell proliferation in areas of brain involved in learning, memory, and sensory stimuli integration. Furthermore, we showed how enriched environmental conditions affect adult neurogenesis. © 2017 Wiley Periodicals, Inc.

Convergent dysregulation of frontal cortical cognitive and reward systems in eating disorders.

PubMed

Stefano, George B; Ptáček, Radek; Kuželová, Hana; Mantione, Kirk J; Raboch, Jiří; Papezova, Hana; Kream, Richard M

2013-05-10

A substantive literature has drawn a compelling case for the functional involvement of mesolimbic/prefrontal cortical neural reward systems in normative control of eating and in the etiology and persistence of severe eating disorders that affect diverse human populations. Presently, we provide a short review that develops an equally compelling case for the importance of dysregulated frontal cortical cognitive neural networks acting in concert with regional reward systems in the regulation of complex eating behaviors and in the presentation of complex pathophysiological symptoms associated with major eating disorders. Our goal is to highlight working models of major eating disorders that incorporate complementary approaches to elucidate functionally interactive neural circuits defined by their regulatory neurochemical phenotypes. Importantly, we also review evidence-based linkages between widely studied psychiatric and neurodegenerative syndromes (e.g., autism spectrum disorders and Parkinson's disease) and co-morbid eating disorders to elucidate basic mechanisms involving dopaminergic transmission and its regulation by endogenously expressed morphine in these same cortical regions.

A review of human-automation interaction and lessons learned

DOT National Transportation Integrated Search

2006-10-01

This report reviews 37 accidents in aviation, other vehicles, process control and other complex systems where human-automation interaction is involved. Implications about causality with respect to design, procedures, management and training are drawn...

Kacang Cerdik: A Conceptual Design of an Idea Management System

ERIC Educational Resources Information Center

Murah, Mohd Zamri; Abdullah, Zuraidah; Hassan, Rosilah; Bakar, Marini Abu; Mohamed, Ibrahim; Amin, Hazilah Mohd

2013-01-01

An idea management system is where ideas are stored and then can be evaluated and analyzed. It provides the structure and the platform for users to contribute ideas for innovation and creativity. Designing and developing an idea management system is a complex task because it involves many users and lot of ideas. Some of the critical features for…

Managing Complex Change in Clinical Study Metadata

PubMed Central

Brandt, Cynthia A.; Gadagkar, Rohit; Rodriguez, Cesar; Nadkarni, Prakash M.

2004-01-01

In highly functional metadata-driven software, the interrelationships within the metadata become complex, and maintenance becomes challenging. We describe an approach to metadata management that uses a knowledge-base subschema to store centralized information about metadata dependencies and use cases involving specific types of metadata modification. Our system borrows ideas from production-rule systems in that some of this information is a high-level specification that is interpreted and executed dynamically by a middleware engine. Our approach is implemented in TrialDB, a generic clinical study data management system. We review approaches that have been used for metadata management in other contexts and describe the features, capabilities, and limitations of our system. PMID:15187070

Systemic and localized scleroderma in children: current and future treatment options.

PubMed

Rosenkranz, Margalit E; Agle, Lucila M A; Efthimiou, Petros; Lehman, Thomas J A

2006-01-01

Scleroderma is a group of rare and complex diseases with varied clinical manifestations. The most obvious manifestation of the diseases is skin hardening and sclerosis. Scleroderma can be divided into two main subgroups: systemic and localized. The systemic form, also known as systemic sclerosis, involves diffuse skin involvement and potentially severe visceral involvement. Localized scleroderma on the other hand is more common in children and usually confined to a specific region of the body with no internal organ involvement. The juvenile forms of systemic sclerosis and localized scleroderma are important conditions in children because of the clinical severity and substantial mortality of systemic scleroderma and the major growth defects associated with childhood-onset localized disease even if the active disease itself is self-limited. The pathogenic pathways of the various forms of scleroderma are only partially defined, but the main defect in scleroderma is abnormal collagen deposition leading to eventual fibrosis in the skin as well as multiple organ systems such as the heart and lungs in juvenile systemic sclerosis. Therapeutics are divided into three main subgroups for systemic sclerosis: antifibrotics, anti-inflammatories, and vasodilators. For localized disease, anti-inflammatories, vitamin D analogs, and UV irradiation have been investigated. However, the infrequency of scleroderma in the pediatric population plus the fact that this disease is very often self-limiting makes randomized controlled trials very difficult. It is for this reason that most data on treatment modalities for this disease have been extrapolated from studies in adult patients. There is no one therapy for systemic sclerosis or localized scleroderma that has proven to be very effective or significantly disease modifying. However, current therapeutic strategies must be initiated early in the disease course for maximum beneficial clinical effects. New interventions such as autologous stem cell transplant and cytokine-directed therapies are under investigation as potential treatments for this complex disease.

"Structure and dynamics in complex chemical systems: Gaining new insights through recent advances in time-resolved spectroscopies.” ACS Division of Physical Chemistry Symposium presented at the Fall National ACS Meeting in Boston, MA, August 2015

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

Crawford, Daniel

8-Session Symposium on STRUCTURE AND DYNAMICS IN COMPLEX CHEMICAL SYSTEMS: GAINING NEW INSIGHTS THROUGH RECENT ADVANCES IN TIME-RESOLVED SPECTROSCOPIES. The intricacy of most chemical, biochemical, and material processes and their applications are underscored by the complex nature of the environments in which they occur. Substantial challenges for building a global understanding of a heterogeneous system include (1) identifying unique signatures associated with specific structural motifs within the heterogeneous distribution, and (2) resolving the significance of each of multiple time scales involved in both small- and large-scale nuclear reorganization. This symposium focuses on the progress in our understanding of dynamics inmore » complex systems driven by recent innovations in time-resolved spectroscopies and theoretical developments. Such advancement is critical for driving discovery at the molecular level facilitating new applications. Broad areas of interest include: Structural relaxation and the impact of structure on dynamics in liquids, interfaces, biochemical systems, materials, and other heterogeneous environments.« less

The Ruler Protein EscP of the Enteropathogenic Escherichia coli Type III Secretion System Is Involved in Calcium Sensing and Secretion Hierarchy Regulation by Interacting with the Gatekeeper Protein SepL

PubMed Central

Shaulov, Lihi; Gershberg, Jenia; Deng, Wanyin; Finlay, B. Brett

2017-01-01

ABSTRACT The type III secretion system (T3SS) is a multiprotein complex that plays a central role in the virulence of many Gram-negative bacterial pathogens. To ensure that effector proteins are efficiently translocated into the host cell, bacteria must be able to sense their contact with the host cell. In this study, we found that EscP, which was previously shown to function as the ruler protein of the enteropathogenic Escherichia coli T3SS, is also involved in the switch from the secretion of translocator proteins to the secretion of effector proteins. In addition, we demonstrated that EscP can interact with the gatekeeper protein SepL and that the EscP-SepL complex dissociates upon a calcium concentration drop. We suggest a model in which bacterial contact with the host cell is accompanied by a drop in the calcium concentration that causes SepL-EscP complex dissociation and triggers the secretion of effector proteins. PMID:28049143

Clinician user involvement in the real world: Designing an electronic tool to improve interprofessional communication and collaboration in a hospital setting.

PubMed

Tang, Terence; Lim, Morgan E; Mansfield, Elizabeth; McLachlan, Alexander; Quan, Sherman D

2018-02-01

User involvement is vital to the success of health information technology implementation. However, involving clinician users effectively and meaningfully in complex healthcare organizations remains challenging. The objective of this paper is to share our real-world experience of applying a variety of user involvement methods in the design and implementation of a clinical communication and collaboration platform aimed at facilitating care of complex hospitalized patients by an interprofessional team of clinicians. We designed and implemented an electronic clinical communication and collaboration platform in a large community teaching hospital. The design team consisted of both technical and healthcare professionals. Agile software development methodology was used to facilitate rapid iterative design and user input. We involved clinician users at all stages of the development lifecycle using a variety of user-centered, user co-design, and participatory design methods. Thirty-six software releases were delivered over 24 months. User involvement has resulted in improvement in user interface design, identification of software defects, creation of new modules that facilitated workflow, and identification of necessary changes to the scope of the project early on. A variety of user involvement methods were complementary and benefited the design and implementation of a complex health IT solution. Combining these methods with agile software development methodology can turn designs into functioning clinical system to support iterative improvement. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Involving Assessment Buddies in the Assessment of Design Project Work

ERIC Educational Resources Information Center

Osmond, Jane; Clough, Brian

2012-01-01

This paper discusses the impact of a specially developed assessment and feedback system implemented within a second year industrial design module at Coventry University, UK. The "Assessment Buddy" system was developed in response to the need for a successful assessment and feedback method that could cope with the complexities of a…

Promoting Strategic STEM Education Outreach Programming Using a Systems-Based STEM-EO Model

ERIC Educational Resources Information Center

Ward, Annmarie R.

2015-01-01

In this paper a STEM Education Outreach (STEM-EO) Model for promoting strategic university outreach programming at Penn State University to the benefit of university, school district and community stakeholders is described. The model considers STEM-EO as a complex system involving overarching learning goals addressed within four outreach domains…

Smaller Satellite Operations Near Geostationary Orbit

DTIC Science & Technology

2007-09-01

At the time, this was considered a very difficult task, due to the complexity involved with creating computer code to autonomously perform... computer systems and even permanently damage equipment. Depending on the solar cycle, solar weather will be properly characterized and modeled to...30 Wayne Tomasi. Electronic Communciations Systems. Upper Saddle River: Pearson Education, 2004. 1041

Video Analysis and Remote Digital Ethnography: Approaches to understanding user perspectives and processes involving healthcare information technology.

PubMed

Kushniruk, Andre W; Borycki, Elizabeth M

2015-01-01

Innovations in healthcare information systems promise to revolutionize and streamline healthcare processes worldwide. However, the complexity of these systems and the need to better understand issues related to human-computer interaction have slowed progress in this area. In this chapter the authors describe their work in using methods adapted from usability engineering, video ethnography and analysis of digital log files for improving our understanding of complex real-world healthcare interactions between humans and technology. The approaches taken are cost-effective and practical and can provide detailed ethnographic data on issues health professionals and consumers encounter while using systems as well as potential safety problems. The work is important in that it can be used in techno-anthropology to characterize complex user interactions with technologies and also to provide feedback into redesign and optimization of improved healthcare information systems.

Analysis of Eye-Tracking Data with Regards to the Complexity of Flight Deck Information Automation and Management - Inattentional Blindness, System State Awareness, and EFB Usage

NASA Technical Reports Server (NTRS)

Dill, Evan T.; Young, Steven D.

2015-01-01

In the constant drive to further the safety and efficiency of air travel, the complexity of avionics-related systems, and the procedures for interacting with these systems, appear to be on an ever-increasing trend. While this growing complexity often yields productive results with respect to system capabilities and flight efficiency, it can place a larger burden on pilots to manage increasing amounts of information and to understand intricate system designs. Evidence supporting this observation is becoming widespread, yet has been largely anecdotal or the result of subjective analysis. One way to gain more insight into this issue is through experimentation using more objective measures or indicators. This study utilizes and analyzes eye-tracking data obtained during a high-fidelity flight simulation study wherein many of the complexities of current flight decks, as well as those planned for the next generation air transportation system (NextGen), were emulated. The following paper presents the findings of this study with a focus on electronic flight bag (EFB) usage, system state awareness (SSA) and events involving suspected inattentional blindness (IB).

Multicore Architecture-aware Scientific Applications

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

Srinivasa, Avinash

Modern high performance systems are becoming increasingly complex and powerful due to advancements in processor and memory architecture. In order to keep up with this increasing complexity, applications have to be augmented with certain capabilities to fully exploit such systems. These may be at the application level, such as static or dynamic adaptations or at the system level, like having strategies in place to override some of the default operating system polices, the main objective being to improve computational performance of the application. The current work proposes two such capabilites with respect to multi-threaded scientific applications, in particular a largemore » scale physics application computing ab-initio nuclear structure. The first involves using a middleware tool to invoke dynamic adaptations in the application, so as to be able to adjust to the changing computational resource availability at run-time. The second involves a strategy for effective placement of data in main memory, to optimize memory access latencies and bandwidth. These capabilties when included were found to have a significant impact on the application performance, resulting in average speedups of as much as two to four times.« less

The adaption and use of research codes for performance assessment

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

Liebetrau, A.M.

1987-05-01

Models of real-world phenomena are developed for many reasons. The models are usually, if not always, implemented in the form of a computer code. The characteristics of a code are determined largely by its intended use. Realizations or implementations of detailed mathematical models of complex physical and/or chemical processes are often referred to as research or scientific (RS) codes. Research codes typically require large amounts of computing time. One example of an RS code is a finite-element code for solving complex systems of differential equations that describe mass transfer through some geologic medium. Considerable computing time is required because computationsmore » are done at many points in time and/or space. Codes used to evaluate the overall performance of real-world physical systems are called performance assessment (PA) codes. Performance assessment codes are used to conduct simulated experiments involving systems that cannot be directly observed. Thus, PA codes usually involve repeated simulations of system performance in situations that preclude the use of conventional experimental and statistical methods. 3 figs.« less

Grounding explanations in evolving, diagnostic situations

NASA Technical Reports Server (NTRS)

Johannesen, Leila J.; Cook, Richard I.; Woods, David D.

1994-01-01

Certain fields of practice involve the management and control of complex dynamic systems. These include flight deck operations in commercial aviation, control of space systems, anesthetic management during surgery or chemical or nuclear process control. Fault diagnosis of these dynamic systems generally must occur with the monitored process on-line and in conjunction with maintaining system integrity.This research seeks to understand in more detail what it means for an intelligent system to function cooperatively, or as a 'team player' in complex, dynamic environments. The approach taken was to study human practitioners engaged in the management of a complex, dynamic process: anesthesiologists during neurosurgical operations. The investigation focused on understanding how team members cooperate in management and fault diagnosis and comparing this interaction to the situation with an Artificial Intelligence(AI) system that provides diagnoses and explanations. Of particular concern was to study the ways in which practitioners support one another in keeping aware of relevant information concerning the state of the monitored process and of the problem solving process.

Computer modeling of Epilepsy

PubMed Central

Lytton, William W.

2009-01-01

Preface Epilepsy is a complex set of disorders that can involve many areas of cortex as well as underlying deep brain systems. The myriad manifestations of seizures, as varied as déjà vu and olfactory hallucination, can thereby give researchers insights into regional functions and relations. Epilepsy is also complex genetically and pathophysiologically, involving microscopic (ion channels, synaptic proteins), macroscopic (brain trauma and rewiring) and intermediate changes in a complex interplay of causality. It has long been recognized that computer modeling will be required to disentangle causality, to better understand seizure spread and to understand and eventually predict treatment efficacy. Over the past few years, substantial progress has been made modeling epilepsy at levels ranging from the molecular to the socioeconomic. We review these efforts and connect them to the medical goals of understanding and treating this disorder. PMID:18594562

Research approaches to mass casualty incidents response: development from routine perspectives to complexity science.

PubMed

Shen, Weifeng; Jiang, Libing; Zhang, Mao; Ma, Yuefeng; Jiang, Guanyu; He, Xiaojun

2014-01-01

To review the research methods of mass casualty incident (MCI) systematically and introduce the concept and characteristics of complexity science and artificial system, computational experiments and parallel execution (ACP) method. We searched PubMed, Web of Knowledge, China Wanfang and China Biology Medicine (CBM) databases for relevant studies. Searches were performed without year or language restrictions and used the combinations of the following key words: "mass casualty incident", "MCI", "research method", "complexity science", "ACP", "approach", "science", "model", "system" and "response". Articles were searched using the above keywords and only those involving the research methods of mass casualty incident (MCI) were enrolled. Research methods of MCI have increased markedly over the past few decades. For now, dominating research methods of MCI are theory-based approach, empirical approach, evidence-based science, mathematical modeling and computer simulation, simulation experiment, experimental methods, scenario approach and complexity science. This article provides an overview of the development of research methodology for MCI. The progresses of routine research approaches and complexity science are briefly presented in this paper. Furthermore, the authors conclude that the reductionism underlying the exact science is not suitable for MCI complex systems. And the only feasible alternative is complexity science. Finally, this summary is followed by a review that ACP method combining artificial systems, computational experiments and parallel execution provides a new idea to address researches for complex MCI.

Inflammation as a Therapeutic Target for Diabetic Neuropathies

PubMed Central

Ang, Lynn; Holmes, Crystal; Gallagher, Katherine; Feldman, Eva L.

2016-01-01

Diabetic neuropathies (DNs) are one of the most prevalent chronic complications of diabetes and a major cause of disability, high mortality, and poor quality of life. Given the complex anatomy of the peripheral nervous system and types of fiber dysfunction, DNs have a wide spectrum of clinical manifestations. The treatment of DNs continues to be challenging, likely due to the complex pathogenesis that involves an array of systemic and cellular imbalances in glucose and lipids metabolism. These lead to the activation of various biochemical pathways, including increased oxidative/nitrosative stress, activation of the polyol and protein kinase C pathways, activation of polyADP ribosylation, and activation of genes involved in neuronal damage, cyclooxygenase-2 activation, endothelial dysfunction, altered Na+/K+-ATPase pump function, impaired C-peptide-related signaling pathways, endoplasmic reticulum stress, and low-grade inflammation. This review summarizes current evidence regarding the role of low-grade inflammation as a potential therapeutic target for DNs. PMID:26897744

Genes of the major histocompatibility complex highlight interactions of the innate and adaptive immune system

PubMed Central

Lukasch, Barbara; Westerdahl, Helena; Strandh, Maria; Winkler, Hans; Moodley, Yoshan; Knauer, Felix

2017-01-01

Background A well-functioning immune defence is crucial for fitness, but our knowledge about the immune system and its complex interactions is still limited. Major histocompatibility complex (MHC) molecules are involved in T-cell mediated adaptive immune responses, but MHC is also highly upregulated during the initial innate immune response. The aim of our study was therefore to determine to what extent the highly polymorphic MHC is involved in interactions of the innate and adaptive immune defence and if specific functional MHC alleles (FA) or heterozygosity at the MHC are more important. Methods To do this we used captive house sparrows (Passer domesticus) to survey MHC diversity and immune function controlling for several environmental factors. MHC class I alleles were identified using parallel amplicon sequencing and to mirror immune function, several immunological tests that correspond to the innate and adaptive immunity were conducted. Results Our results reveal that MHC was linked to all immune tests, highlighting its importance for the immune defence. While all innate responses were associated with one single FA, adaptive responses (cell-mediated and humoral) were associated with several different alleles. Discussion We found that repeated injections of an antibody in nestlings and adults were linked to different FA and hence might affect different areas of the immune system. Also, individuals with a higher number of different FA produced a smaller secondary response, indicating a disadvantage of having numerous MHC alleles. These results demonstrate the complexity of the immune system in relation to the MHC and lay the foundation for other studies to further investigate this topic. PMID:28875066

Genes of the major histocompatibility complex highlight interactions of the innate and adaptive immune system.

PubMed

Lukasch, Barbara; Westerdahl, Helena; Strandh, Maria; Winkler, Hans; Moodley, Yoshan; Knauer, Felix; Hoi, Herbert

2017-01-01

A well-functioning immune defence is crucial for fitness, but our knowledge about the immune system and its complex interactions is still limited. Major histocompatibility complex (MHC) molecules are involved in T-cell mediated adaptive immune responses, but MHC is also highly upregulated during the initial innate immune response. The aim of our study was therefore to determine to what extent the highly polymorphic MHC is involved in interactions of the innate and adaptive immune defence and if specific functional MHC alleles (FA) or heterozygosity at the MHC are more important. To do this we used captive house sparrows ( Passer domesticus ) to survey MHC diversity and immune function controlling for several environmental factors. MHC class I alleles were identified using parallel amplicon sequencing and to mirror immune function, several immunological tests that correspond to the innate and adaptive immunity were conducted. Our results reveal that MHC was linked to all immune tests, highlighting its importance for the immune defence. While all innate responses were associated with one single FA, adaptive responses (cell-mediated and humoral) were associated with several different alleles. We found that repeated injections of an antibody in nestlings and adults were linked to different FA and hence might affect different areas of the immune system. Also, individuals with a higher number of different FA produced a smaller secondary response, indicating a disadvantage of having numerous MHC alleles. These results demonstrate the complexity of the immune system in relation to the MHC and lay the foundation for other studies to further investigate this topic.

A New Socio-technical Model for Studying Health Information Technology in Complex Adaptive Healthcare Systems

PubMed Central

Sittig, Dean F.; Singh, Hardeep

2011-01-01

Conceptual models have been developed to address challenges inherent in studying health information technology (HIT). This manuscript introduces an 8-dimensional model specifically designed to address the socio-technical challenges involved in design, development, implementation, use, and evaluation of HIT within complex adaptive healthcare systems. The 8 dimensions are not independent, sequential, or hierarchical, but rather are interdependent and interrelated concepts similar to compositions of other complex adaptive systems. Hardware and software computing infrastructure refers to equipment and software used to power, support, and operate clinical applications and devices. Clinical content refers to textual or numeric data and images that constitute the “language” of clinical applications. The human computer interface includes all aspects of the computer that users can see, touch, or hear as they interact with it. People refers to everyone who interacts in some way with the system, from developer to end-user, including potential patient-users. Workflow and communication are the processes or steps involved in assuring that patient care tasks are carried out effectively. Two additional dimensions of the model are internal organizational features (e.g., policies, procedures, and culture) and external rules and regulations, both of which may facilitate or constrain many aspects of the preceding dimensions. The final dimension is measurement and monitoring, which refers to the process of measuring and evaluating both intended and unintended consequences of HIT implementation and use. We illustrate how our model has been successfully applied in real-world complex adaptive settings to understand and improve HIT applications at various stages of development and implementation. PMID:20959322

A new sociotechnical model for studying health information technology in complex adaptive healthcare systems.

PubMed

Sittig, Dean F; Singh, Hardeep

2010-10-01

Conceptual models have been developed to address challenges inherent in studying health information technology (HIT). This manuscript introduces an eight-dimensional model specifically designed to address the sociotechnical challenges involved in design, development, implementation, use and evaluation of HIT within complex adaptive healthcare systems. The eight dimensions are not independent, sequential or hierarchical, but rather are interdependent and inter-related concepts similar to compositions of other complex adaptive systems. Hardware and software computing infrastructure refers to equipment and software used to power, support and operate clinical applications and devices. Clinical content refers to textual or numeric data and images that constitute the 'language' of clinical applications. The human--computer interface includes all aspects of the computer that users can see, touch or hear as they interact with it. People refers to everyone who interacts in some way with the system, from developer to end user, including potential patient-users. Workflow and communication are the processes or steps involved in ensuring that patient care tasks are carried out effectively. Two additional dimensions of the model are internal organisational features (eg, policies, procedures and culture) and external rules and regulations, both of which may facilitate or constrain many aspects of the preceding dimensions. The final dimension is measurement and monitoring, which refers to the process of measuring and evaluating both intended and unintended consequences of HIT implementation and use. We illustrate how our model has been successfully applied in real-world complex adaptive settings to understand and improve HIT applications at various stages of development and implementation.

An Improved Method to Control the Critical Parameters of a Multivariable Control System

NASA Astrophysics Data System (ADS)

Subha Hency Jims, P.; Dharmalingam, S.; Wessley, G. Jims John

2017-10-01

The role of control systems is to cope with the process deficiencies and the undesirable effect of the external disturbances. Most of the multivariable processes are highly iterative and complex in nature. Aircraft systems, Modern Power Plants, Refineries, Robotic systems are few such complex systems that involve numerous critical parameters that need to be monitored and controlled. Control of these important parameters is not only tedious and cumbersome but also is crucial from environmental, safety and quality perspective. In this paper, one such multivariable system, namely, a utility boiler has been considered. A modern power plant is a complex arrangement of pipework and machineries with numerous interacting control loops and support systems. In this paper, the calculation of controller parameters based on classical tuning concepts has been presented. The controller parameters thus obtained and employed has controlled the critical parameters of a boiler during fuel switching disturbances. The proposed method can be applied to control the critical parameters like elevator, aileron, rudder, elevator trim rudder and aileron trim, flap control systems of aircraft systems.

Vestiges of Submarine Serpentinization Recorded in the Microbiology of Continental Ophiolite Complexes

NASA Astrophysics Data System (ADS)

Schrenk, M. O.; Sabuda, M.; Brazelton, W. J.; Twing, K. I.

2017-12-01

The study of serpentinization-influenced microbial ecosystems at and below the seafloor has accelerated in recent years with multidisciplinary drilling expeditions to the Atlantis Massif (X357), Southwest Indian Ridge (X360) and Mariana Forearc (X366). In parallel, a number of studies have surveyed serpentinizing systems in ophiolite complexes which host a range of geologic histories, geochemical characteristics, fluid pathways, and consequently microbiology. As ophiolite complexes originate as seafloor materials, it is likely that a microbiological record of seafloor serpentinization processes is maintained through the emplacement and weathering of continental serpentinites. This hypothesis was evaluated through a global comparison of continental serpentinite springs and groundwater, ranging from highly brackish (saline) to freshwater. One of the most saline sites, known as the Coast Range Ophiolite Microbial Observatory (CROMO), was used as a point-of-comparison to marine serpentinizing systems, such as the Lost City Hydrothermal Field. Although there was little taxonomic overlap between microbial populations in marine and terrestrial systems, both communities harbored an abundance of genes involved in sulfur metabolism, including sulfide oxidation, thiosulfate disproportionation, and sulfate reduction. The phylogeny of key genes involved in these metabolic processes was evaluated relative to published studies and compared between sites. Together, these data provide insights into both the functioning of microbial communities in modern-day serpentinizing systems, and the transport processes that disperse microorganisms between marine and terrestrial serpentinites.

Studies on Cu(II) ternary complexes involving an aminopenicillin drug and imidazole containing ligands

NASA Astrophysics Data System (ADS)

Regupathy, Sthanumoorthy; Nair, Madhavan Sivasankaran

2010-02-01

Equilibrium studies on the ternary complex systems involving ampicillin (amp) as ligand (A) and imidazole containing ligands viz., imidazole (Him), benzimidazole (Hbim), histamine (Hist) and histidine (His) as ligands (B) at 37 °C and I = 0.15 mol dm -3 (NaClO 4) show the presence of CuABH, CuAB and CuAB 2. The proton in the CuABH species is attached to ligand A. In the ternary complexes the ligand, amp(A) binds the metal ion via amino nitrogen and carbonyl oxygen atom. The CuAB (B = Hist/His)/CuAB 2 (B = Him/Hbim) species have also been isolated and the analytical data confirmed its formation. Non-electrolytic behavior and monomeric type of chelates have been assessed from their low conductance and magnetic susceptibility values. The electronic and vibrational spectral results were interpreted to find the mode of binding of ligands to metal and geometry of the complexes. This is also supported by the g tensor values calculated from ESR spectra. The thermal behaviour of complexes were studied by TGA/DTA. The redox behavior of the complexes has been studied by cyclic voltammetry. The antimicrobial activity and CT DNA cleavage study of the complexes show higher activity for ternary complexes.

Application of simplified Complexity Theory concepts for healthcare social systems to explain the implementation of evidence into practice.

PubMed

Chandler, Jacqueline; Rycroft-Malone, Jo; Hawkes, Claire; Noyes, Jane

2016-02-01

To examine the application of core concepts from Complexity Theory to explain the findings from a process evaluation undertaken in a trial evaluating implementation strategies for recommendations about reducing surgical fasting times. The proliferation of evidence-based guidance requires a greater focus on its implementation. Theory is required to explain the complex processes across the multiple healthcare organizational levels. This social healthcare context involves the interaction between professionals, patients and the organizational systems in care delivery. Complexity Theory may provide an explanatory framework to explain the complexities inherent in implementation in social healthcare contexts. A secondary thematic analysis of qualitative process evaluation data informed by Complexity Theory. Seminal texts applying Complexity Theory to the social context were annotated, key concepts extracted and core Complexity Theory concepts identified. These core concepts were applied as a theoretical lens to provide an explanation of themes from a process evaluation of a trial evaluating the implementation of strategies to reduce surgical fasting times. Sampled substantive texts provided a representative spread of theoretical development and application of Complexity Theory from late 1990's-2013 in social science, healthcare, management and philosophy. Five Complexity Theory core concepts extracted were 'self-organization', 'interaction', 'emergence', 'system history' and 'temporality'. Application of these concepts suggests routine surgical fasting practice is habituated in the social healthcare system and therefore it cannot easily be reversed. A reduction to fasting times requires an incentivised new approach to emerge in the surgical system's priority of completing the operating list. The application of Complexity Theory provides a useful explanation for resistance to change fasting practice. Its utility in implementation research warrants further attention and evaluation. © 2015 John Wiley & Sons Ltd.

Landscape change in the Southern Piedmont: Challenges, solutions and uncertainty across scales

USGS Publications Warehouse

Conroy, M.J.; Allen, Craig R.; Peterson, J.T.; Pritchard, L.; Moore, C.T.

2003-01-01

The southern Piedmont of the southeastern United States epitomizes the complex and seemingly intractable problems and hard decisions that result from uncontrolled urban and suburban sprawl. Here we consider three recurrent themes in complicated problems involving complex systems: (1) scale dependencies and cross-scale, often nonlinear relationships; (2) resilience, in particular the potential for complex systems to move to alternate stable states with decreased ecological and/or economic value; and (3) uncertainty in the ability to understand and predict outcomes, perhaps particularly those that occur as a result of human impacts. We consider these issues in the context of landscape-level decision making, using as an example water resources and lotic systems in the Piedmont region of the southeastern United States. Copyright ?? 2003 by the author(s). Published here under licence by The Resilience Alliance.

Multi-Agent-Based Simulation of a Complex Ecosystem of Mental Health Care.

PubMed

Kalton, Alan; Falconer, Erin; Docherty, John; Alevras, Dimitris; Brann, David; Johnson, Kyle

2016-02-01

This paper discusses the creation of an Agent-Based Simulation that modeled the introduction of care coordination capabilities into a complex system of care for patients with Serious and Persistent Mental Illness. The model describes the engagement between patients and the medical, social and criminal justice services they interact with in a complex ecosystem of care. We outline the challenges involved in developing the model, including process mapping and the collection and synthesis of data to support parametric estimates, and describe the controls built into the model to support analysis of potential changes to the system. We also describe the approach taken to calibrate the model to an observable level of system performance. Preliminary results from application of the simulation are provided to demonstrate how it can provide insights into potential improvements deriving from introduction of care coordination technology.

Identification of the Mitochondrial Heme Metabolism Complex

PubMed Central

Medlock, Amy E.; Shiferaw, Mesafint T.; Marcero, Jason R.; Vashisht, Ajay A.; Wohlschlegel, James A.; Phillips, John D.; Dailey, Harry A.

2015-01-01

Heme is an essential cofactor for most organisms and all metazoans. While the individual enzymes involved in synthesis and utilization of heme are fairly well known, less is known about the intracellular trafficking of porphyrins and heme, or regulation of heme biosynthesis via protein complexes. To better understand this process we have undertaken a study of macromolecular assemblies associated with heme synthesis. Herein we have utilized mass spectrometry with coimmunoprecipitation of tagged enzymes of the heme biosynthetic pathway in a developing erythroid cell culture model to identify putative protein partners. The validity of these data obtained in the tagged protein system is confirmed by normal porphyrin/heme production by the engineered cells. Data obtained are consistent with the presence of a mitochondrial heme metabolism complex which minimally consists of ferrochelatase, protoporphyrinogen oxidase and aminolevulinic acid synthase-2. Additional proteins involved in iron and intermediary metabolism as well as mitochondrial transporters were identified as potential partners in this complex. The data are consistent with the known location of protein components and support a model of transient protein-protein interactions within a dynamic protein complex. PMID:26287972

A Systems Approach to Public School Reform: Implications for the Use of Social Systems Design in a Small Rural School

ERIC Educational Resources Information Center

Rawlins, Holly

2007-01-01

How can a community ensure that its public schools reflect local values and beliefs about education? The complexities involved in the reform of existing public schools, or the creation of a new system of schooling, have caused some researchers to explore new methodological avenues to change (Banathy, 1991; Duffy, Rogerson, & Blick, 2000;…

Systems Biology for Smart Crops and Agricultural Innovation: Filling the Gaps between Genotype and Phenotype for Complex Traits Linked with Robust Agricultural Productivity and Sustainability

PubMed Central

Pathak, Rajesh Kumar; Gupta, Sanjay Mohan; Gaur, Vikram Singh; Pandey, Dinesh

2015-01-01

Abstract In recent years, rapid developments in several omics platforms and next generation sequencing technology have generated a huge amount of biological data about plants. Systems biology aims to develop and use well-organized and efficient algorithms, data structure, visualization, and communication tools for the integration of these biological data with the goal of computational modeling and simulation. It studies crop plant systems by systematically perturbing them, checking the gene, protein, and informational pathway responses; integrating these data; and finally, formulating mathematical models that describe the structure of system and its response to individual perturbations. Consequently, systems biology approaches, such as integrative and predictive ones, hold immense potential in understanding of molecular mechanism of agriculturally important complex traits linked to agricultural productivity. This has led to identification of some key genes and proteins involved in networks of pathways involved in input use efficiency, biotic and abiotic stress resistance, photosynthesis efficiency, root, stem and leaf architecture, and nutrient mobilization. The developments in the above fields have made it possible to design smart crops with superior agronomic traits through genetic manipulation of key candidate genes. PMID:26484978

Genetic predisposition to peripheral nerve neoplasia: Diagnostic criteria and pathogenesis of neurofibromatoses, Carney complex, and related syndromes

PubMed Central

Rodriguez, Fausto J.; Stratakis, Constantine A.; Evans, D Gareth

2013-01-01

Neoplasms of the peripheral nerve sheath represent essential clinical manifestations of the syndromes known as the neurofibromatoses. Although involvement of multiple organ systems, including skin, central nervous system and skeleton, may also be conspicuous, peripheral nerve neoplasia is often the most important and frequent cause of morbidity in these patients. Clinical characteristics of neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2) have been extensively described and studied during the last century, and the identification of mutations in the NF1 and NF2 genes by contemporary molecular techniques have created a separate multidisciplinary field in genetic medicine. In schwannomatosis, the most recent addition to the neurofibromatosis group, peripheral nervous system involvement is the exclusive (or almost exclusive) clinical manifestation. Although the majority of cases of schwannomatosis are sporadic, approximately a third occur in families and a subset of these has recently been associated with germline mutations in the tumor suppressor gene SMARCB1/INI1. Other curious syndromes that involve the peripheral nervous system are associated with predominant endocrine manifestations, and include Carney Complex and MEN2b, secondary to inactivating mutations in the PRKAR1A gene in a subset, and activating mutations in RET respectively. In this review, we provide a concise update on the diagnostic criteria, pathology and molecular pathogenesis of these enigmatic syndromes in relation to peripheral nerve sheath neoplasia. PMID:22210082

Genetic predisposition to peripheral nerve neoplasia: diagnostic criteria and pathogenesis of neurofibromatoses, Carney complex, and related syndromes.

PubMed

Rodriguez, Fausto J; Stratakis, Constantine A; Evans, D Gareth

2012-03-01

Neoplasms of the peripheral nerve sheath represent essential clinical manifestations of the syndromes known as the neurofibromatoses. Although involvement of multiple organ systems, including skin, central nervous system, and skeleton, may also be conspicuous, peripheral nerve neoplasia is often the most important and frequent cause of morbidity in these patients. Clinical characteristics of neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2) have been extensively described and studied during the last century, and the identification of mutations in the NF1 and NF2 genes by contemporary molecular techniques have created a separate multidisciplinary field in genetic medicine. In schwannomatosis, the most recent addition to the neurofibromatosis group, peripheral nervous system involvement is the exclusive (or almost exclusive) clinical manifestation. Although the majority of cases of schwannomatosis are sporadic, approximately one-third occur in families and a subset of these has recently been associated with germline mutations in the tumor suppressor gene SMARCB1/INI1. Other curious syndromes that involve the peripheral nervous system are associated with predominant endocrine manifestations, and include Carney complex and MEN2b, secondary to inactivating mutations in the PRKAR1A gene in a subset, and activating mutations in RET, respectively. In this review, we provide a concise update on the diagnostic criteria, pathology and molecular pathogenesis of these enigmatic syndromes in relation to peripheral nerve sheath neoplasia.

Dynamical analysis of the global business-cycle synchronization

PubMed Central

2018-01-01

This paper reports the dynamical analysis of the business cycles of 12 (developed and developing) countries over the last 56 years by applying computational techniques used for tackling complex systems. They reveal long-term convergence and country-level interconnections because of close contagion effects caused by bilateral networking exposure. Interconnectivity determines the magnitude of cross-border impacts. Local features and shock propagation complexity also may be true engines for local configuration of cycles. The algorithmic modeling proves to represent a solid approach to study the complex dynamics involved in the world economies. PMID:29408909

Dynamical analysis of the global business-cycle synchronization.

PubMed

Lopes, António M; Tenreiro Machado, J A; Huffstot, John S; Mata, Maria Eugénia

2018-01-01

This paper reports the dynamical analysis of the business cycles of 12 (developed and developing) countries over the last 56 years by applying computational techniques used for tackling complex systems. They reveal long-term convergence and country-level interconnections because of close contagion effects caused by bilateral networking exposure. Interconnectivity determines the magnitude of cross-border impacts. Local features and shock propagation complexity also may be true engines for local configuration of cycles. The algorithmic modeling proves to represent a solid approach to study the complex dynamics involved in the world economies.

Identifying behaviour patterns of construction safety using system archetypes.

PubMed

Guo, Brian H W; Yiu, Tak Wing; González, Vicente A

2015-07-01

Construction safety management involves complex issues (e.g., different trades, multi-organizational project structure, constantly changing work environment, and transient workforce). Systems thinking is widely considered as an effective approach to understanding and managing the complexity. This paper aims to better understand dynamic complexity of construction safety management by exploring archetypes of construction safety. To achieve this, this paper adopted the ground theory method (GTM) and 22 interviews were conducted with participants in various positions (government safety inspector, client, health and safety manager, safety consultant, safety auditor, and safety researcher). Eight archetypes were emerged from the collected data: (1) safety regulations, (2) incentive programs, (3) procurement and safety, (4) safety management in small businesses (5) production and safety, (6) workers' conflicting goals, (7) blame on workers, and (8) reactive and proactive learning. These archetypes capture the interactions between a wide range of factors within various hierarchical levels and subsystems. As a free-standing tool, they advance the understanding of dynamic complexity of construction safety management and provide systemic insights into dealing with the complexity. They also can facilitate system dynamics modelling of construction safety process. Copyright © 2015 Elsevier Ltd. All rights reserved.

Self-dissimilarity as a High Dimensional Complexity Measure

NASA Technical Reports Server (NTRS)

Wolpert, David H.; Macready, William

2005-01-01

For many systems characterized as "complex" the patterns exhibited on different scales differ markedly from one another. For example the biomass distribution in a human body "looks very different" depending on the scale at which one examines it. Conversely, the patterns at different scales in "simple" systems (e.g., gases, mountains, crystals) vary little from one scale to another. Accordingly, the degrees of self-dissimilarity between the patterns of a system at various scales constitute a complexity "signature" of that system. Here we present a novel quantification of self-dissimilarity. This signature can, if desired, incorporate a novel information-theoretic measure of the distance between probability distributions that we derive here. Whatever distance measure is chosen, our quantification of self-dissimilarity can be measured for many kinds of real-world data. This allows comparisons of the complexity signatures of wholly different kinds of systems (e.g., systems involving information density in a digital computer vs. species densities in a rain-forest vs. capital density in an economy, etc.). Moreover, in contrast to many other suggested complexity measures, evaluating the self-dissimilarity of a system does not require one to already have a model of the system. These facts may allow self-dissimilarity signatures to be used a s the underlying observational variables of an eventual overarching theory relating all complex systems. To illustrate self-dissimilarity we present several numerical experiments. In particular, we show that underlying structure of the logistic map is picked out by the self-dissimilarity signature of time series produced by that map

Decision Making Under Uncertainty and Complexity: A Model-Based Scenario Approach to Supporting Integrated Water Resources Management

NASA Astrophysics Data System (ADS)

Liu, Y.; Gupta, H.; Wagener, T.; Stewart, S.; Mahmoud, M.; Hartmann, H.; Springer, E.

2007-12-01

Some of the most challenging issues facing contemporary water resources management are those typified by complex coupled human-environmental systems with poorly characterized uncertainties. In other words, major decisions regarding water resources have to be made in the face of substantial uncertainty and complexity. It has been suggested that integrated models can be used to coherently assemble information from a broad set of domains, and can therefore serve as an effective means for tackling the complexity of environmental systems. Further, well-conceived scenarios can effectively inform decision making, particularly when high complexity and poorly characterized uncertainties make the problem intractable via traditional uncertainty analysis methods. This presentation discusses the integrated modeling framework adopted by SAHRA, an NSF Science & Technology Center, to investigate stakeholder-driven water sustainability issues within the semi-arid southwestern US. The multi-disciplinary, multi-resolution modeling framework incorporates a formal scenario approach to analyze the impacts of plausible (albeit uncertain) alternative futures to support adaptive management of water resources systems. Some of the major challenges involved in, and lessons learned from, this effort will be discussed.

Surficial geological tools in fluvial geomorphology: Chapter 2

USGS Publications Warehouse

Jacobson, Robert B.; O'Connor, James E.; Oguchi, Takashi

2016-01-01

Increasingly, environmental scientists are being asked to develop an understanding of how rivers and streams have been altered by environmental stresses, whether rivers are subject to physical or chemical hazards, how they can be restored, and how they will respond to future environmental change. These questions present substantive challenges to the discipline of fluvial geomorphology, especially since decades of geomorphologic research have demonstrated the general complexity of fluvial systems. It follows from the concept of complex response that synoptic and short-term historical views of rivers will often give misleading understanding of future behavior. Nevertheless, broadly trained geomorphologists can address questions involving complex natural systems by drawing from a tool box that commonly includes the principles and methods of geology, hydrology, hydraulics, engineering, and ecology.

Nonlinear Systems.

ERIC Educational Resources Information Center

Seider, Warren D.; Ungar, Lyle H.

1987-01-01

Describes a course in nonlinear mathematics courses offered at the University of Pennsylvania which provides an opportunity for students to examine the complex solution spaces that chemical engineers encounter. Topics include modeling many chemical processes, especially those involving reaction and diffusion, auto catalytic reactions, phase…

Asthma and Respiratory Allergic Disease

EPA Science Inventory

The pathogenesis of non-communicable diseases such as allergy is complex and poorly understood. The causes of chronic allergic diseases including asthma involve to a large extent, immunomodulation of the adaptive and particularly the innate immune systems and are markedly influen...

Thermal Quantum Correlations in Photosynthetic Light-Harvesting Complexes

NASA Astrophysics Data System (ADS)

Mahdian, M.; Kouhestani, H.

2015-08-01

Photosynthesis is one of the ancient biological processes, playing crucial role converting solar energy to cellular usable currency. Environmental factors and external perturbations has forced nature to choose systems with the highest efficiency and performance. Recent theoretical and experimental studies have proved the presence of quantum properties in biological systems. Energy transfer systems like Fenna-Matthews-Olson (FMO) complex shows quantum entanglement between sites of Bacteriophylla molecules in protein environment and presence of decoherence. Complex biological systems implement more truthful mechanisms beside chemical-quantum correlations to assure system's efficiency. In this study we investigate thermal quantum correlations in FMO protein of the photosynthetic apparatus of green sulfur bacteria by quantum discord measure. The results confirmed existence of remarkable quantum correlations of of BChla pigments in room temperature. This results approve involvement of quantum correlation mechanisms for information storage and retention in living organisms that could be useful for further evolutionary studies. Inspired idea of this study is potentially interesting to practice by the same procedure in genetic data transfer mechanisms.

Vesicular trafficking of immune mediators in human eosinophils revealed by immunoelectron microscopy

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

Melo, Rossana C.N., E-mail: rossana.melo@ufjf.edu.br; Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, CLS 943, Boston, MA 02215; Weller, Peter F.

Electron microscopy (EM)-based techniques are mostly responsible for our current view of cell morphology at the subcellular level and continue to play an essential role in biological research. In cells from the immune system, such as eosinophils, EM has helped to understand how cells package and release mediators involved in immune responses. Ultrastructural investigations of human eosinophils enabled visualization of secretory processes in detail and identification of a robust, vesicular trafficking essential for the secretion of immune mediators via a non-classical secretory pathway associated with secretory (specific) granules. This vesicular system is mainly organized as large tubular-vesicular carriers (Eosinophil Sombreromore » Vesicles – EoSVs) actively formed in response to cell activation and provides a sophisticated structural mechanism for delivery of granule-stored mediators. In this review, we highlight the application of EM techniques to recognize pools of immune mediators at vesicular compartments and to understand the complex secretory pathway within human eosinophils involved in inflammatory and allergic responses. - Highlights: • Application of EM to understand the complex secretory pathway in human eosinophils. • EM techniques reveal an active vesicular system associated with secretory granules. • Tubular vesicles are involved in the transport of granule-derived immune mediators.« less

Coherent Patterns in Nuclei and in Financial Markets

NASA Astrophysics Data System (ADS)

DroŻdŻ, S.; Kwapień, J.; Speth, J.

2010-07-01

In the area of traditional physics the atomic nucleus belongs to the most complex systems. It involves essentially all elements that characterize complexity including the most distinctive one whose essence is a permanent coexistence of coherent patterns and of randomness. From a more interdisciplinary perspective, these are the financial markets that represent an extreme complexity. Here, based on the matrix formalism, we set some parallels between several characteristics of complexity in the above two systems. We, in particular, refer to the concept—historically originating from nuclear physics considerations—of the random matrix theory and demonstrate its utility in quantifying characteristics of the coexistence of chaos and collectivity also for the financial markets. In this later case we show examples that illustrate mapping of the matrix formulation into the concepts originating from the graph theory. Finally, attention is drawn to some novel aspects of the financial coherence which opens room for speculation if analogous effects can be detected in the atomic nuclei or in other strongly interacting Fermi systems.

Biomimicry Promotes the Efficiency of a 10-Step Sequential Enzymatic Reaction on Nanoparticles, Converting Glucose to Lactate.

PubMed

Mukai, Chinatsu; Gao, Lizeng; Nelson, Jacquelyn L; Lata, James P; Cohen, Roy; Wu, Lauren; Hinchman, Meleana M; Bergkvist, Magnus; Sherwood, Robert W; Zhang, Sheng; Travis, Alexander J

2017-01-02

For nanobiotechnology to achieve its potential, complex organic-inorganic systems must grow to utilize the sequential functions of multiple biological components. Critical challenges exist: immobilizing enzymes can block substrate-binding sites or prohibit conformational changes, substrate composition can interfere with activity, and multistep reactions risk diffusion of intermediates. As a result, the most complex tethered reaction reported involves only 3 enzymes. Inspired by the oriented immobilization of glycolytic enzymes on the fibrous sheath of mammalian sperm, here we show a complex reaction of 10 enzymes tethered to nanoparticles. Although individual enzyme efficiency was higher in solution, the efficacy of the 10-step pathway measured by conversion of glucose to lactate was significantly higher when tethered. To our knowledge, this is the most complex organic-inorganic system described, and it shows that tethered, multi-step biological pathways can be reconstituted in hybrid systems to carry out functions such as energy production or delivery of molecular cargo. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biomimicry promotes the efficiency of a 10-step sequential enzymatic reaction on nanoparticles, converting glucose to lactate

PubMed Central

Mukai, Chinatsu; Gao, Lizeng; Nelson, Jacquelyn L.; Lata, James P.; Cohen, Roy; Wu, Lauren; Hinchman, Meleana M.; Bergkvist, Magnus; Sherwood, Robert W.; Zhang, Sheng; Travis, Alexander J.

2016-01-01

For nanobiotechnology to achieve its potential, complex organic-inorganic systems must grow to utilize the sequential functions of multiple biological components. Critical challenges exist: immobilizing enzymes can block substrate-binding sites or prohibit conformational changes, substrate composition can interfere with activity, and multistep reactions risk diffusion of intermediates. As a result, the most complex tethered reaction reported involves only 3 enzymes. Inspired by the oriented immobilization of glycolytic enzymes on the fibrous sheath of mammalian sperm, here we show a complex reaction of 10 enzymes tethered to nanoparticles. Although individual enzyme efficiency was higher in solution, the efficacy of the 10-step pathway measured by conversion of glucose to lactate was significantly higher when tethered. To our knowledge, this is the most complex organic-inorganic system described, and it shows that tethered, multi-step biological pathways can be reconstituted in hybrid systems to carry out functions such as energy production or delivery of molecular cargo. PMID:27901298

Associative and sensorimotor learning for parenting involves mirror neurons under the influence of oxytocin.

PubMed

Ho, S Shaun; Macdonald, Adam; Swain, James E

2014-04-01

Mirror neuron-based associative learning may be understood according to associative learning theories, in addition to sensorimotor learning theories. This is important for a comprehensive understanding of the role of mirror neurons and related hormone modulators, such as oxytocin, in complex social interactions such as among parent-infant dyads and in examples of mirror neuron function that involve abnormal motor systems such as depression.

Layers of Symbiosis - Visualizing the Termite Hindgut Microbial Community

PubMed Central

Leadbetter, Jared

2007-01-01

Jared Leadbetter takes us for a nature walk through the diversity of life resident in the termite hindgut - a microenvironment containing 250 different species found nowhere else on Earth. Jared reveals that the symbiosis exhibited by this system is multi-layered and involves not only a relationship between the termite and its gut inhabitants, but also involves a complex web of symbiosis among the gut microbes themselves. PMID:18979002

Biological system interactions.

PubMed Central

Adomian, G; Adomian, G E; Bellman, R E

1984-01-01

Mathematical modeling of cellular population growth, interconnected subsystems of the body, blood flow, and numerous other complex biological systems problems involves nonlinearities and generally randomness as well. Such problems have been dealt with by mathematical methods often changing the actual model to make it tractable. The method presented in this paper (and referenced works) allows much more physically realistic solutions. PMID:6585837

Understanding the Online Informal Learning of English as a Complex Dynamic System: An Emic Approach

ERIC Educational Resources Information Center

Sockett, Geoffrey

2013-01-01

Research into the online informal learning of English has already shown it to be a widespread phenomenon involving a range of comprehension and production activities such as viewing original version television series, listening to music on demand and social networking with other English users. Dynamic systems theory provides a suitable framework…

Coupled Pendulums: A Physical System for Laboratory Investigations at Upper Secondary School

ERIC Educational Resources Information Center

Picciarelli, Vittorio; Stella, Rosa

2010-01-01

The topic of coupled oscillations is rich in physical content which is both interesting and complex. The study of the time evolution of coupled oscillator systems involves a mathematical formalization beyond the level of the upper secondary school student's competence. Here, we present an original approach, suitable even for secondary students, to…

One Teacher, 20 Preschoolers, and a Goldfish Environmental Awareness, Emergent Curriculum, and Documentation

ERIC Educational Resources Information Center

Lewin-Benham, Ann

2006-01-01

Teaching Preschoolers about the environment is hard. Many complex concepts are involved: the interactions among everything on the planet--air, land, water, and all living things; the systems that determine weather and climate, food supply, energy resources, and the quality of life for every plant and animal; systems operating on a planetary scale…

The capuchin monkey as a flight candidate

NASA Technical Reports Server (NTRS)

Winget, C. M.

1977-01-01

The highly evolved nervous system and associated complex behavioral capabilities of the nonhuman primates make them good candidates for certain studies in the space environment since deleterious changes in these more complex aspects of a biological status can only be demonstrated by species which share such highly evolved features with man. Important assets which urge the selection of the capuchin monkey for space experiments include his small size, high intelligence, relative disease resistance, nutritional requirements, and lower volume life support systems. The species is particularly suited for experiments on the nervous system or on process under neural control because of the similarity of capuchin and human blood chemistry profiles and endocrine systems involved in the maintenance of homeostasis and vasomotor tone.

Practicality of electronic beam steering for MST/ST radars, part 6.2A

NASA Technical Reports Server (NTRS)

Clark, W. L.; Green, J. L.

1984-01-01

Electronic beam steering is described as complex and expensive. The Sunset implementation of electronic steering is described, and it is demonstrated that such systems are cost effective, versatile, and no more complex than fixed beam alternatives, provided three or more beams are needed. The problem of determining accurate meteorological wind components in the presence of spatial variation is considered. A cost comparison of steerable and fixed systems allowing solution of this problem is given. The concepts and relations involved in phase steering are given, followed by the description of the Sunset ST radar steering system. The implications are discussed, references to the competing SAD method are provided, and a recommendation concerning the design of the future Doppler ST/MST systems is made.

Foreign currency-related translation complexities in cross-border healthcare applications.

PubMed

Kumar, Anand; Rodrigues, Jean M

2009-01-01

International cross-border private hospital chains need to apply the standards for foreign currency translation in order to consolidate the balance sheet and income statements. This not only exposes such chains to exchange rate fluctuations in different ways, but also creates added requirements for enterprise-level IT systems especially when they produce parameters which are used to measure the financial and operational performance of the foreign subsidiary or the parent hospital. Such systems would need to come to terms with the complexities involved in such currency-related translations in order to provide the correct data for performance benchmarking.

Characterizing Density and Complexity of Imported Cargos

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

Birrer, Nathaniel; Divin, Charles; Glenn, Steven

X-ray inspection systems are used to detect radiological and nuclear threats in imported cargo. In order to better understand performance of these systems, system imaging capabilities and the characteristics of imported cargo need to be determined. This project involved calculation of the modulation transfer function as a metric of system imaging performance and a study of the density and inhomogeneity of imported cargos, which have been shown to correlate with human analysts, threat detection performance.

Benchmarking the Naval Systems Engineering Guide Against the Industry Standards for Systems Engineering

DTIC Science & Technology

2012-09-01

Maintenance activities, as this will allow new methods and Operational changes to be made if necessary (i.e., more downtime than originally planned or...increased complexity of military hardware, both new systems and their integration with legacy systems, requires a correspondingly increased expertise in...available Little of that added weight involves weapons or armor that actually is becoming lighter as new technologies and composites are utilized (Task

Systems engineering and integration processes involved with manned mission operations

NASA Technical Reports Server (NTRS)

Kranz, Eugene F.; Kraft, Christopher C.

1993-01-01

This paper will discuss three mission operations functions that are illustrative of the key principles of operations SE&I and of the processes and products involved. The flight systems process was selected to illustrate the role of the systems product line in developing the depth and cross disciplinary skills needed for SE&I and providing the foundation for dialogue between participating elements. FDDD was selected to illustrate the need for a structured process to assure that SE&I provides complete and accurate results that consistently support program needs. The flight director's role in mission operations was selected to illustrate the complexity of the risk/gain tradeoffs involved in the development of the flight techniques and flight rules process as well as the absolute importance of the leadership role in developing the technical, operational, and political trades.

Moving sociohydrology forward: a synthesis across studies

NASA Astrophysics Data System (ADS)

Troy, T. J.; Konar, M.; Srinivasan, V.; Thompson, S.

2015-03-01

Sociohydrology is the study of coupled human-water systems with the premise that water and human systems co-evolve, often with two-way coupling. A recent special issue in HESS/ESD, "Predictions under change: water, earth, and biota in the Anthropocene", includes a number of sociohydrologic publications that allow for a survey of the current state of understanding of sociohydrology and the coupled system dynamics and feedbacks, the research methodologies available, and the norms and ethics involved in studying sociohydrologic systems. Although sociohydrology is concerned with coupled human-water systems, it is critical to consider the sociohydrologic system as embedded in a larger, complex social-ecological system through which human-water feedbacks can occur and from which the sociohydrologic system cannot be isolated. As such, sociohydrology can draw on tools developed in the social-ecological and complex systems literature to further our sociohydrologic knowledge, and this is identified as a ripe area of future research.

The Caenorhabditis elegans Excretory System: A Model for Tubulogenesis, Cell Fate Specification, and Plasticity

PubMed Central

Sundaram, Meera V.; Buechner, Matthew

2016-01-01

The excretory system of the nematode Caenorhabditis elegans is a superb model of tubular organogenesis involving a minimum of cells. The system consists of just three unicellular tubes (canal, duct, and pore), a secretory gland, and two associated neurons. Just as in more complex organs, cells of the excretory system must first adopt specific identities and then coordinate diverse processes to form tubes of appropriate topology, shape, connectivity, and physiological function. The unicellular topology of excretory tubes, their varied and sometimes complex shapes, and the dynamic reprogramming of cell identity and remodeling of tube connectivity that occur during larval development are particularly fascinating features of this organ. The physiological roles of the excretory system in osmoregulation and other aspects of the animal’s life cycle are only beginning to be explored. The cellular mechanisms and molecular pathways used to build and shape excretory tubes appear similar to those used in both unicellular and multicellular tubes in more complex organs, such as the vertebrate vascular system and kidney, making this simple organ system a useful model for understanding disease processes. PMID:27183565

Computer modelling of epilepsy.

PubMed

Lytton, William W

2008-08-01

Epilepsy is a complex set of disorders that can involve many areas of the cortex, as well as underlying deep-brain systems. The myriad manifestations of seizures, which can be as varied as déjà vu and olfactory hallucination, can therefore give researchers insights into regional functions and relations. Epilepsy is also complex genetically and pathophysiologically: it involves microscopic (on the scale of ion channels and synaptic proteins), macroscopic (on the scale of brain trauma and rewiring) and intermediate changes in a complex interplay of causality. It has long been recognized that computer modelling will be required to disentangle causality, to better understand seizure spread and to understand and eventually predict treatment efficacy. Over the past few years, substantial progress has been made in modelling epilepsy at levels ranging from the molecular to the socioeconomic. We review these efforts and connect them to the medical goals of understanding and treating the disorder.

An Ontology for Modeling Complex Inter-relational Organizations

NASA Astrophysics Data System (ADS)

Wautelet, Yves; Neysen, Nicolas; Kolp, Manuel

This paper presents an ontology for organizational modeling through multiple complementary aspects. The primary goal of the ontology is to dispose of an adequate set of related concepts for studying complex organizations involved in a lot of relationships at the same time. In this paper, we define complex organizations as networked organizations involved in a market eco-system that are playing several roles simultaneously. In such a context, traditional approaches focus on the macro analytic level of transactions; this is supplemented here with a micro analytic study of the actors' rationale. At first, the paper overviews enterprise ontologies literature to position our proposal and exposes its contributions and limitations. The ontology is then brought to an advanced level of formalization: a meta-model in the form of a UML class diagram allows to overview the ontology concepts and their relationships which are formally defined. Finally, the paper presents the case study on which the ontology has been validated.

Could ecosystem management provide a new framework for Alzheimer's disease?

PubMed

Hubin, Ellen; Vanschoenwinkel, Bram; Broersen, Kerensa; De Deyn, Peter P; Koedam, Nico; van Nuland, Nico A; Pauwels, Kris

2016-01-01

Alzheimer's disease (AD) is a progressive neurodegenerative brain disorder that involves a plethora of molecular pathways. In the context of therapeutic treatment and biomarker profiling, the amyloid-beta (Aβ) peptide constitutes an interesting research avenue that involves interactions within a complex mixture of Aβ alloforms and other disease-modifying factors. Here, we explore the potential of an ecosystem paradigm as a novel way to consider AD and Aβ dynamics in particular. We discuss the example that the complexity of the Aβ network not only exhibits interesting parallels with the functioning of complex systems such as ecosystems but that this analogy can also provide novel insights into the neurobiological phenomena in AD and serve as a communication tool. We propose that combining network medicine with general ecosystem management principles could be a new and holistic approach to understand AD pathology and design novel therapies. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Intelligent systems engineering methodology

NASA Technical Reports Server (NTRS)

Fouse, Scott

1990-01-01

An added challenge for the designers of large scale systems such as Space Station Freedom is the appropriate incorporation of intelligent system technology (artificial intelligence, expert systems, knowledge-based systems, etc.) into their requirements and design. This presentation will describe a view of systems engineering which successfully addresses several aspects of this complex problem: design of large scale systems, design with requirements that are so complex they only completely unfold during the development of a baseline system and even then continue to evolve throughout the system's life cycle, design that involves the incorporation of new technologies, and design and development that takes place with many players in a distributed manner yet can be easily integrated to meet a single view of the requirements. The first generation of this methodology was developed and evolved jointly by ISX and the Lockheed Aeronautical Systems Company over the past five years on the Defense Advanced Research Projects Agency/Air Force Pilot's Associate Program, one of the largest, most complex, and most successful intelligent systems constructed to date. As the methodology has evolved it has also been applied successfully to a number of other projects. Some of the lessons learned from this experience may be applicable to Freedom.

Flipping the NF-κB Switch in Macrophages | Center for Cancer Research

Cancer.gov

A critical component of the innate immune system, macrophages respond to diverse microbes by recognizing certain molecular patterns, such as the Gram-negative bacteria product lipopolysaccharide (LPS), via Toll-like receptors. Receptor activation stimulates a complex signaling network that involves, among others, the NF-κB pathway. The complexity of this network has hampered researchers’ understanding of how macrophages resolve conflicting signals to determine when to mount an immune response.

A theoretical study of complexes formed between cations and curved aromatic systems: electrostatics does not always control cation-π interaction.

PubMed

Carrazana-García, Jorge A; Cabaleiro-Lago, Enrique M; Rodríguez-Otero, Jesús

2017-04-19

The present work studies the interaction of two extended curved π-systems (corannulene and sumanene) with various cations (sodium, potassium, ammonium, tetramethylammonium, guanidinium and imidazolium). Polyatomic cations are models of groups found in important biomolecules in which cation-π interaction plays a fundamental role. The results indicate an important size effect: with extended π systems and cations of the size of potassium and larger, dispersion is much more important than has been generally recognized for cation-π interactions. In most of the systems studied here, the stability of the cation-π complexes is the result of a balanced combination of electrostatic, induction and dispersion contributions. None of the systems studied here owes its stability to the electrostatic interaction more than 42%. Induction dominates stabilization in complexes with sodium, and in some of the potassium and ammonium complexes. In complexes with large cations and with flat cations dispersion is the major stabilizing contribution and can provide more than 50% of the stabilization energy. This implies that theoretical studies of the cation-π interaction involving large or even medium-size fragments require a level of calculation capable of properly modelling dispersion. The separation between the cation and the π system is another important factor to take into account, especially when the fragments of the cation-π complex are bound (for example, to a protein backbone) and cannot interact at the most favourable distance.

Cyberinfrastructure: The Second Revolution

ERIC Educational Resources Information Center

Bement, Arden L.

2007-01-01

The engine of change for the next revolution is cyberinfrastructure, a comprehensive phenomenon that involves the creation, dissemination, preservation, and application of knowledge. It adds new dimensions that greatly increase transformational potential. Cyberinfrastructure combines complex elements to create a dynamic system. It eclipses its…

On some stochastic formulations and related statistical moments of pharmacokinetic models.

PubMed

Matis, J H; Wehrly, T E; Metzler, C M

1983-02-01

This paper presents the deterministic and stochastic model for a linear compartment system with constant coefficients, and it develops expressions for the mean residence times (MRT) and the variances of the residence times (VRT) for the stochastic model. The expressions are relatively simple computationally, involving primarily matrix inversion, and they are elegant mathematically, in avoiding eigenvalue analysis and the complex domain. The MRT and VRT provide a set of new meaningful response measures for pharmacokinetic analysis and they give added insight into the system kinetics. The new analysis is illustrated with an example involving the cholesterol turnover in rats.

Structural characterization of molecular complexes formed by trimethoprim and cimitidine with 2,3,5,6-tetrachloro-1,4-benzoquinone

NASA Astrophysics Data System (ADS)

Balraj, C.; Ganesh, K.; Elango, K. P.

2011-07-01

Spectroscopic and spectrofluorimetric techniques have been employed to investigate the structure of the charge transfer (CT) complexes of Trimethoprim (TMP) and Cimitidine (CTD) drugs with 2,3,5,6-tetrachloro-1,4-benzoquinone ( p-chloranil, p-CHL). The stoichiometry of the complexes was found to be 1:2 for TMP- p-CHL system and 1:1 for CTD- p-CHL system. The thermodynamic results indicated that the formation of molecular complex between the donors and the acceptor is spontaneous and endothermic. The results of electronic spectral studies indicated that the formation constant for CTD- p-CHL system is found to be higher than that for TMP- p-CHL system. The observation is well supported by the results of fluorescence quenching studies and the association constants calculated for CTD- p-CHL system is 36.2 × 10 3 mol L -1 and that for TMP- p-CHL system is 2.6 × 10 3 mol L -1. The kinetic results, in both the cases, indicated that the interaction is first order each with respect to the concentration of the donor and the acceptor. The physico-chemical parameters viz. oscillator strength, dipole moment, ionization potential and dissociation energy of the complexes were also determined and discussed. Structural characterization of the complexes were done using FT-IR and 1H NMR spectral techniques and the results indicated that, in TMP, the free NH 2 group while in CTD the pyrazole N sbnd H moiety involves in complexation with the acceptor, p-CHL.

Using emergent order to shape a space society

NASA Technical Reports Server (NTRS)

Graps, Amara L.

1993-01-01

A fast-growing movement in the scientific community is reshaping the way that we view the world around us. The short-hand name for this movement is 'chaos'. Chaos is a science of the global, nonlinear nature of systems. The center of this set of ideas is that simple, deterministic systems can breed complexity. Systems as complex as the human body, ecology, the mind or a human society. While it is true that simple laws can breed complexity, the other side is that complex systems can breed order. It is the latter that I will focus on in this paper. In the past, nonlinear was nearly synonymous with unsolvable because no general analytic solutions exist. Mathematically, an essential difference exists between linear and nonlinear systems. For linear systems, you just break up the complicated system into many simple pieces and patch together the separated solutions for each piece to form a solution to the full problem. In contrast, solutions to a nonlinear system cannot be added to form a new solution. The system must be treated in its full complexity. While it is true that no general analytical approach exists for reducing a complex system such as a society, it can be modeled. The technical involves a mathematical construct called phase space. In this space stable structures can appear which I use as analogies for the stable structures that appear in a complex system such as an ecology, the mind or a society. The common denominator in all of these systems is that they rely on a process called feedback loops. Feedback loops link the microscopic (individual) parts to the macroscopic (global) parts. The key, then, in shaping a space society, is in effectively using feedback loops. This paper will illustrate how one can model a space society by using methods that chaoticists have developed over the last hundred years. And I will show that common threads exist in the modeling of biological, economical, philosophical, and sociological systems.

Copper(II) complexes with uridine, uridine 5'-monophosphate, spermidine, or spermine in aqueous solution.

PubMed

Lomozik, Lechoslaw; Jastrzab, Renata

2003-01-15

Molecular complexes of the types (Urd)H(x)(PA) and (UMP)H(x)(PA) are formed in the uridine (Urd) or uridine 5'-monophosphate (UMP) plus spermidine or spermine systems, as shown by the results of equilibrium and spectral studies. Overall stability constants of the adducts and equilibrium constants of their formation have been determined. An increase in the efficiency of the reaction between the bioligands is observed with increasing length of the polyamine. The pH range of adduct formation is found to coincide with that in which the polyamine is protonated while uridine or its monophosphate is deprotonated. The -NH(x)(+) groups from PA and the N(3) atom of the purine base as well as phosphate groups from the nucleotides have been identified as the significant centres of non-covalent interactions. Compared to cytidine, the pH range of Urd adduct formation is shifted significantly higher due to differences in the protonation constants of the endocyclic N(3) donor atoms of particular nucleosides. Overall stability constants of the Cu(II) complexes with uridine and uridine 5'-monophosphate in ternary systems with spermidine or spermine have been determined. It has been found from spectral data that in the Cu(II) ternary complexes with nucleosides and polyamines the reaction of metallation involves mainly N(3) atoms from the pyrimidine bases, as well as the amine groups of PA. This unexpected type of interaction has been evidenced in the coordination mode of the complexes forming in the Cu-UMP systems including spermidine or spermine. Results of spectral and equilibrium studies indicate that the phosphate groups taking part in metallation are at the same time involved in non-covalent interaction with the protonated polyamine.

Role of organic cation/carnitine transporter 1 in uptake of phenformin and inhibitory effect on complex I respiration in mitochondria.

PubMed

Shitara, Yoshihisa; Nakamichi, Noritaka; Norioka, Misaki; Shima, Hiroyo; Kato, Yukio; Horie, Toshiharu

2013-03-01

Phenformin causes lactic acidosis in clinical situations due to inhibition of mitochondrial respiratory chain complex I. It is reportedly taken up by hepatocytes and exhibits mitochondrial toxicity in the liver. In this study, uptake of phenformin and [(14)C]tetraethylammonium (TEA) and complex I inhibition by phenformin were examined in isolated liver and heart mitochondria. Uptake of phenformin into isolated rat liver mitochondria was higher than that into heart mitochondria. It was inhibited by several cat ionic compounds, which suggests the involvement of multispecific transport system(s). Similar characteristics were also observed for uptake of TEA; however, uptake of phenformin into mitochondria of organic cation/carnitine transporter 1 (OCTN1) knockout mice was lower than that in wild-type mice, whereas uptake of TEA was comparable between the two strains, suggesting the involvement of distinct transport mechanisms for these two cations in mitochondria. Inhibition by phenformin of oxygen consumption via complex I respiration in isolated rat liver mitochondria was greater than that in heart mitochondria, whereas inhibitory effect of phenformin on complex I respiration was similar in inside-out structured submitochondrial particles prepared from rat livers and hearts. Lactic acidosis provoked by iv infusion of phenformin was weaker in octn1(-/-) mice than that in wild-type mice. These observations suggest that uptake of phenformin into liver mitochondria is at least partly mediated by OCTN1 and functionally relevant to its inhibition potential of complex I respiration. This study was, thus, the first to demonstrate OCTN1-mediated mitochondrial transport and toxicity of biguanide in vivo in rodents.

N-cadherin in adult rat cardiomyocytes in culture. II. Spatio-temporal appearance of proteins involved in cell-cell contact and communication. Formation of two distinct N-cadherin/catenin complexes.

PubMed

Hertig, C M; Butz, S; Koch, S; Eppenberger-Eberhardt, M; Kemler, R; Eppenberger, H M

1996-01-01

The spatio-temporal appearance and distribution of proteins forming the intercalated disc were investigated in adult rat cardiomyocytes (ARC). The 'redifferentiation model' of ARC involves extensive remodelling of the plasma membrane and of the myofibrillar apparatus. It represents a valuable system to elucidate the formation of cell-cell contact between cardiomyocytes and to assess the mechanisms by which different proteins involved in the cell-cell adhesion process are sorted in a precise manner to the sites of function. Appearance of N-cadherin, the catenins and connexin43 within newly formed adherens and gap junctions was studied. Here first evidence is provided for a formation of two distinct and separable N-cadherin/catenin complexes in cardiomyocytes. Both complexes are composed of N-cadherin and alpha-catenin which bind to either beta-catenin or plakoglobin in a mutually exclusive manner. The two N-cadherin/catenin complexes are assumed to be functionally involved in the formation of cell-cell contacts in ARC; however, the differential appearance and localization of the two types of complexes may also point to a specific role during ARC differentiation. The newly synthesized beta-catenin containing complex is more abundant during the first stages in culture after ARC isolation, while the newly synthesized plakoglobin containing complex progressively accumulates during the morphological changes of ARC. ARC formed a tissue-like pattern in culture whereby the new cell-cell contacts could be dissolved through Ca2+ depletion. Presence of cAMP and replenishment of Ca2+ content in the culture medium not only allowed reformation of cell-cell contacts but also affected the relative protein ratio between the two N-cadherin/catenin complexes, increasing the relative amount of newly synthesized beta-catenin over plakoglobin at a particular stage of ARC differentiation. The clustered N-cadherin/catenin complexes at the plasma membrane appear to be a prerequisite for the following gap junction formation; a temporal sequence of the appearance of adherens junction proteins and of gap junctions forming connexin-43 is suggested.

Theoretical Foundation of Copernicus: A Unified System for Trajectory Design and Optimization

NASA Technical Reports Server (NTRS)

Ocampo, Cesar; Senent, Juan S.; Williams, Jacob

2010-01-01

The fundamental methods are described for the general spacecraft trajectory design and optimization software system called Copernicus. The methods rely on a unified framework that is used to model, design, and optimize spacecraft trajectories that may operate in complex gravitational force fields, use multiple propulsion systems, and involve multiple spacecraft. The trajectory model, with its associated equations of motion and maneuver models, are discussed.

Convolving engineering and medical pedagogies for training of tomorrow's health care professionals.

PubMed

Lee, Raphael C

2013-03-01

Several fundamental benefits justify why biomedical engineering and medicine should form a more convergent alliance, especially for the training of tomorrow's physicians and biomedical engineers. Herein, we review the rationale underlying the benefits. Biological discovery has advanced beyond the era of molecular biology well into today's era of molecular systems biology, which focuses on understanding the rules that govern the behavior of complex living systems. This has important medical implications. To realize cost-effective personalized medicine, it is necessary to translate the advances in molecular systems biology to higher levels of biological organization (organ, system, and organismal levels) and then to develop new medical therapeutics based on simulation and medical informatics analysis. Higher education in biological and medical sciences must adapt to a new set of training objectives. This will involve a shifting away from reductionist problem solving toward more integrative, continuum, and predictive modeling approaches which traditionally have been more associated with engineering science. Future biomedical engineers and MDs must be able to predict clinical response to therapeutic intervention. Medical education will involve engineering pedagogies, wherein basic governing rules of complex system behavior and skill sets in manipulating these systems to achieve a practical desired outcome are taught. Similarly, graduate biomedical engineering programs will include more practical exposure to clinical problem solving.

Synthetic mixed-signal computation in living cells

PubMed Central

Rubens, Jacob R.; Selvaggio, Gianluca; Lu, Timothy K.

2016-01-01

Living cells implement complex computations on the continuous environmental signals that they encounter. These computations involve both analogue- and digital-like processing of signals to give rise to complex developmental programs, context-dependent behaviours and homeostatic activities. In contrast to natural biological systems, synthetic biological systems have largely focused on either digital or analogue computation separately. Here we integrate analogue and digital computation to implement complex hybrid synthetic genetic programs in living cells. We present a framework for building comparator gene circuits to digitize analogue inputs based on different thresholds. We then demonstrate that comparators can be predictably composed together to build band-pass filters, ternary logic systems and multi-level analogue-to-digital converters. In addition, we interface these analogue-to-digital circuits with other digital gene circuits to enable concentration-dependent logic. We expect that this hybrid computational paradigm will enable new industrial, diagnostic and therapeutic applications with engineered cells. PMID:27255669

[Role of psychosocial stress in complex diseases].

PubMed

Scantamburlo, G; Scheen, A J

2012-01-01

Complex diseases are chronic diseases where the interrelations between genetic predisposition and environmental factors play an essential role in the arisen and the maintenance of the pathology. Upon psychological stress, the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system are activated resulting in release of glucocorticoids and catecholamines. Chronic stress may induce complex diseases where alterations of nervous, endocrine and immune systems are involved. Thus, chronic stress is more likely to induce a range of effects, depending on the capacity of the subject to cope with stress. CRH ("Corticotropin Releasing Hormone") is a key factor in the stress-immunity relationship. In this article, we propose an overview of the interrelations between central nervous, endocrine and immune systems and implications for health and diseases. The objective for the clinician is to propose therapeutic strategies targeting changes in human behaviour to cope with a potentially stressful environment.

Analysis of a display and control system man-machine interface concept. Volume 1: Final technical report

NASA Technical Reports Server (NTRS)

Karl, D. R.

1972-01-01

An evaluation was made of the feasibility of utilizing a simplified man machine interface concept to manage and control a complex space system involving multiple redundant computers that control multiple redundant subsystems. The concept involves the use of a CRT for display and a simple keyboard for control, with a tree-type control logic for accessing and controlling mission, systems, and subsystem elements. The concept was evaluated in terms of the Phase B space shuttle orbiter, to utilize the wide scope of data management and subsystem control inherent in the central data management subsystem provided by the Phase B design philosophy. Results of these investigations are reported in four volumes.

Pleural and pulmonary involvement in systemic lupus erythematosus.

PubMed

Torre, Olga; Harari, Sergio

2011-01-01

Systemic lupus erythematosus (SLE) is a rare complex autoimmune disease with a multisystem involvement. The clinical manifestations of this disease include an erythematous rash, oral ulcers, polyarthralgia, nonerosive arthritis, polyserositis, hematologic, renal, neurologic, pulmonary and cardiac abnormalties. The involvement of the respiratory system is frequent. Pleuro-pulmonary manifestations are present in almost half of the patients during the disease course and may be the presenting symptoms in 4-5% of patients with SLE. Complications directly associated to the disease include pleuritis with or without pleural effusion, alveolitis, interstitial lung disease, lupus pneumonitis, pulmonary hemorrhage, pulmonary arterial hypertension, and pulmonary thromboembolic disease. Complications due to secondary causes include pleuro-pulmonary manifestations of cardiac and renal failure, atelectasis due to diaphragmatic dysfunction, opportunistic pneumonia, and drug toxicity. The prevalence, clinical presentation, prognosis and response to treatment vary, depending on the pattern of involvement. As with other connective tissue diseases, early and specific therapeutic intervention may be indicated for many of these pleuro-pulmonary manifestations. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Scaling up ART adherence clubs in the public sector health system in the Western Cape, South Africa: a study of the institutionalisation of a pilot innovation.

PubMed

MacGregor, Hayley; McKenzie, Andrew; Jacobs, Tanya; Ullauri, Angelica

2018-04-25

In 2011, a decision was made to scale up a pilot innovation involving 'adherence clubs' as a form of differentiated care for HIV positive people in the public sector antiretroviral therapy programme in the Western Cape Province of South Africa. In 2016 we were involved in the qualitative aspect of an evaluation of the adherence club model, the overall objective of which was to assess the health outcomes for patients accessing clubs through epidemiological analysis, and to conduct a health systems analysis to evaluate how the model of care performed at scale. In this paper we adopt a complex adaptive systems lens to analyse planned organisational change through intervention in a state health system. We explore the challenges associated with taking to scale a pilot that began as a relatively simple innovation by a non-governmental organisation. Our analysis reveals how a programme initially representing a simple, unitary system in terms of management and clinical governance had evolved into a complex, differentiated care system. An innovation that was assessed as an excellent idea and received political backing, worked well whilst supported on a small scale. However, as scaling up progressed, challenges have emerged at the same time as support has waned. We identified a 'tipping point' at which the system was more likely to fail, as vulnerabilities magnified and the capacity for adaptation was exceeded. Yet the study also revealed the impressive capacity that a health system can have for catalysing novel approaches. We argue that innovation in largescale, complex programmes in health systems is a continuous process that requires ongoing support and attention to new innovation as challenges emerge. Rapid scaling up is also likely to require recourse to further resources, and a culture of iterative learning to address emerging challenges and mitigate complex system errors. These are necessary steps to the future success of adherence clubs as a cornerstone of differentiated care. Further research is needed to assess the equity and quality outcomes of a differentiated care model and to ensure the inclusive distribution of the benefits to all categories of people living with HIV.

Vascular lumen formation.

PubMed

Lammert, Eckhard; Axnick, Jennifer

2012-04-01

The vascular system developed early in evolution. It is required in large multicellular organisms for the transport of nutrients, oxygen, and waste products to and from tissues. The vascular system is composed of hollow tubes, which have a high level of complexity in vertebrates. Vasculogenesis describes the de novo formation of blood vessels, e.g., aorta formation in vertebrate embryogenesis. In contrast, angiogenesis is the formation of blood vessels from preexisting ones, e.g., sprouting of intersomitic blood vessels from the aorta. Importantly, the lumen of all blood vessels in vertebrates is lined and formed by endothelial cells. In both vasculogenesis and angiogenesis, lumen formation takes place in a cord of endothelial cells. It involves a complex molecular mechanism composed of endothelial cell repulsion at the cell-cell contacts within the endothelial cell cords, junctional rearrangement, and endothelial cell shape change. As the vascular system also participates in the course of many diseases, such as cancer, stroke, and myocardial infarction, it is important to understand and make use of the molecular mechanisms of blood vessel formation to better understand and manipulate the pathomechanisms involved.

Fish pigmentation and the melanocortin system.

PubMed

Cal, Laura; Suarez-Bregua, Paula; Cerdá-Reverter, José Miguel; Braasch, Ingo; Rotllant, Josep

2017-09-01

The melanocortin system is a complex neuroendocrine signaling mechanism involved in numerous physiological processes in vertebrates, including pigmentation, steroidogenesis and metabolic control. This review focuses at one of its most fascinating function in fish, its regulatory role in the control of pigmentation, in which the melanocortin 1 receptor (Mc1r), its agonist α-melanocyte stimulating hormone (α-Msh), and the endogenous antagonist agouti signaling protein (Asip1) are the main players. Functional control of Mc1r, which is highly expressed in fish skin and whose activation stimulates melanin production and melanosome dispersion in fish melanophores, is considered a key mechanism for vertebrate pigment phenotypes. The α-Msh peptide, the most documented Mc1r agonist involved in pigmentation, is produced in the pituitary gland, activating melanin synthesis by binding to Mc1r in fish melanophores. Finally, Asip1 is the putative factor for establishing the evolutionarily conserved dorso-ventral pigment pattern found across vertebrates. However, we are just starting to understand how other melanocortin system components are acting in this complex regulatory network. Copyright © 2017 Elsevier Inc. All rights reserved.

Parallel Architectures and Parallel Algorithms for Integrated Vision Systems. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Choudhary, Alok Nidhi

1989-01-01

Computer vision is regarded as one of the most complex and computationally intensive problems. An integrated vision system (IVS) is a system that uses vision algorithms from all levels of processing to perform for a high level application (e.g., object recognition). An IVS normally involves algorithms from low level, intermediate level, and high level vision. Designing parallel architectures for vision systems is of tremendous interest to researchers. Several issues are addressed in parallel architectures and parallel algorithms for integrated vision systems.

Autonomous Control of Nuclear Power Plants

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

Basher, H.

2003-10-20

A nuclear reactor is a complex system that requires highly sophisticated controllers to ensure that desired performance and safety can be achieved and maintained during its operations. Higher-demanding operational requirements such as reliability, lower environmental impacts, and improved performance under adverse conditions in nuclear power plants, coupled with the complexity and uncertainty of the models, necessitate the use of an increased level of autonomy in the control methods. In the opinion of many researchers, the tasks involved during nuclear reactor design and operation (e.g., design optimization, transient diagnosis, and core reload optimization) involve important human cognition and decisions that maymore » be more easily achieved with intelligent methods such as expert systems, fuzzy logic, neural networks, and genetic algorithms. Many experts in the field of control systems share the idea that a higher degree of autonomy in control of complex systems such as nuclear plants is more easily achievable through the integration of conventional control systems and the intelligent components. Researchers have investigated the feasibility of the integration of fuzzy logic, neural networks, genetic algorithms, and expert systems with the conventional control methods to achieve higher degrees of autonomy in different aspects of reactor operations such as reactor startup, shutdown in emergency situations, fault detection and diagnosis, nuclear reactor alarm processing and diagnosis, and reactor load-following operations, to name a few. With the advancement of new technologies and computing power, it is feasible to automate most of the nuclear reactor control and operation, which will result in increased safety and economical benefits. This study surveys current status, practices, and recent advances made towards developing autonomous control systems for nuclear reactors.« less

Single stage queueing/manufacturing system model that involves emission variable

NASA Astrophysics Data System (ADS)

Murdapa, P. S.; Pujawan, I. N.; Karningsih, P. D.; Nasution, A. H.

2018-04-01

Queueing is commonly occured at every industry. The basic model of queueing theory gives a foundation for modeling a manufacturing system. Nowadays, carbon emission is an important and inevitable issue due to its huge impact to our environment. However, existing model of queuing applied for analysis of single stage manufacturing system has not taken Carbon emissions into consideration. If it is applied to manufacturing context, it may lead to improper decisisions. By taking into account of emission variables into queuing models, not only the model become more comprehensive but also it creates awareness on the issue to many parties that involves in the system. This paper discusses the single stage M/M/1 queueing model that involves emission variable. Hopefully it could be a starting point for the next more complex models. It has a main objective for determining how carbon emissions could fit into the basic queueing theory. It turned out that the involvement of emission variables into the model has modified the traditional model of a single stage queue to a calculation model of production lot quantity allowed per period.

Use of Antibiotic-Impregnated Absorbable Beads and Tissue Coverage of Complex Wounds.

PubMed

White, Terris L; Culliford, Alfred T; Zomaya, Martin; Freed, Gary; Demas, Christopher P

2016-11-01

The treatment of complex wounds is commonplace for plastic surgeons. Standard management is debridement of infected and devitalized tissue and systemic antibiotic therapy. In cases where vital structures are exposed within the wound, coverage is obtained with the use of vascularized tissue using both muscle and fasciocutaneous flaps. The use of nondissolving polymethylmethacrylate and absorbable antibiotic-impregnated beads has been shown to deliver high concentrations of antibiotics with low systemic levels of the same antibiotic. We present a multicenter retrospective review of all cases that used absorbable antibiotic-impregnated beads for complex wound management from 2003 to 2013. A total of 104 cases were investigated, flap coverage was used in 97 cases (93.3%). Overall, 15 patients (14.4%) required reoperation with the highest groups involving orthopedic wounds and sternal wounds. The advantages of using absorbable antibiotic-impregnated beads in complex infected wounds have been demonstrated with minimal disadvantages. The utilization of these beads is expanding to a variety of complex infectious wounds requiring high concentrations of local antibiotics.

An Index of Trauma Severity Based on Multiattribute Utility: An Illustration of Complex Utility Modeling.

DTIC Science & Technology

1981-10-01

measure for Central Nervus System is the Glasgow Cons Score (GCS), a scale of brain and spinal cord injury (Langfitt [1978]), and is itself an additive...concerns directly relating to the injury itself were identified. These were: 1. Ventilation Severity 2 Circulation Severity 3. Central Nervous System ...interacting system within which these concerns represent interacting parts. Most trauma involves only one of these systems , but more than one may be

Researching Haptics in Higher Education: The Complexity of Developing Haptics Virtual Learning Systems and Evaluating Its Impact on Students' Learning

ERIC Educational Resources Information Center

San Diego, Jonathan P.; Cox, Margaret J.; Quinn, Barry F. A.; Newton, Jonathan Tim; Banerjee, Avijit; Woolford, Mark

2012-01-01

hapTEL, an interdisciplinary project funded by two UK research councils from 2007 to 2011, involves a large interdisciplinary team (with undergraduate and post-graduate student participants) which has been developing and evaluating a virtual learning system within an HE healthcare education setting, working on three overlapping strands. Strand 1…

Fire danger and fire behavior modeling systems in Australia, Europe, and North America

Treesearch

Francis M. Fujioka; A. Malcolm Gill; Domingos X. Viegas; B. Mike Wotton

2009-01-01

Wildland fire occurrence and behavior are complex phenomena involving essentially fuel (vegetation), topography, and weather. Fire managers around the world use a variety of systems to track and predict fire danger and fire behavior, at spatial scales that span from local to global extents, and temporal scales ranging from minutes to seasons. The fire management...

Interdisciplinary Team Science in Cell Biology.

PubMed

Horwitz, Rick

2016-11-01

The cell is complex. With its multitude of components, spatial-temporal character, and gene expression diversity, it is challenging to comprehend the cell as an integrated system and to develop models that predict its behaviors. I suggest an approach to address this issue, involving system level data analysis, large scale team science, and philanthropy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Abundance of amino acid transporters involved in mTORC1 activation in skeletal muscle of neonatal pigs is developmentally regulated

USDA-ARS?s Scientific Manuscript database

Previously we demonstrated that the insulinand amino acid-induced activation of the mammalian target of rapamycin complex 1 (mTORC1) is developmentally regulated in neonatal pigs. Recent studies have indicated that members of the System A transporter (SNAT2), the System N transporter (SNAT3), the Sy...

The Effects of CALL Program on Expanding Lexical Knowledge of EFL Iranian Intermediate Learners

ERIC Educational Resources Information Center

Ghabanchi, Zargham; Anbarestani, Mojgan

2008-01-01

Foreign language learning is a challenging task, involving mastering a new sound system, phonological and syntactical forms, vocabulary, and sometimes a new writing system. For the adult second language learner, one of the most frustrating aspects is having an inadequate vocabulary for expressing complex ideas that are so easy to relate in one's…

Bridging complexity theory and resilience to develop surge capacity in health systems.

PubMed

Therrien, Marie-Christine; Normandin, Julie-Maude; Denis, Jean-Louis

2017-03-20

Purpose Health systems are periodically confronted by crises - think of Severe Acute Respiratory Syndrome, H1N1, and Ebola - during which they are called upon to manage exceptional situations without interrupting essential services to the population. The ability to accomplish this dual mandate is at the heart of resilience strategies, which in healthcare systems involve developing surge capacity to manage a sudden influx of patients. The paper aims to discuss these issues. Design/methodology/approach This paper relates insights from resilience research to the four "S" of surge capacity (staff, stuff, structures and systems) and proposes a framework based on complexity theory to better understand and assess resilience factors that enable the development of surge capacity in complex health systems. Findings Detailed and dynamic complexities manifest in different challenges during a crisis. Resilience factors are classified according to these types of complexity and along their temporal dimensions: proactive factors that improve preparedness to confront both usual and exceptional requirements, and passive factors that enable response to unexpected demands as they arise during a crisis. The framework is completed by further categorizing resilience factors according to their stabilizing or destabilizing impact, drawing on feedback processes described in complexity theory. Favorable order resilience factors create consistency and act as stabilizing forces in systems, while favorable disorder factors such as diversity and complementarity act as destabilizing forces. Originality/value The framework suggests a balanced and innovative process to integrate these factors in a pragmatic approach built around the fours "S" of surge capacity to increase health system resilience.

A View on Future Building System Modeling and Simulation

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

Wetter, Michael

This chapter presents what a future environment for building system modeling and simulation may look like. As buildings continue to require increased performance and better comfort, their energy and control systems are becoming more integrated and complex. We therefore focus in this chapter on the modeling, simulation and analysis of building energy and control systems. Such systems can be classified as heterogeneous systems because they involve multiple domains, such as thermodynamics, fluid dynamics, heat and mass transfer, electrical systems, control systems and communication systems. Also, they typically involve multiple temporal and spatial scales, and their evolution can be described bymore » coupled differential equations, discrete equations and events. Modeling and simulating such systems requires a higher level of abstraction and modularisation to manage the increased complexity compared to what is used in today's building simulation programs. Therefore, the trend towards more integrated building systems is likely to be a driving force for changing the status quo of today's building simulation programs. Thischapter discusses evolving modeling requirements and outlines a path toward a future environment for modeling and simulation of heterogeneous building systems.A range of topics that would require many additional pages of discussion has been omitted. Examples include computational fluid dynamics for air and particle flow in and around buildings, people movement, daylight simulation, uncertainty propagation and optimisation methods for building design and controls. For different discussions and perspectives on the future of building modeling and simulation, we refer to Sahlin (2000), Augenbroe (2001) and Malkawi and Augenbroe (2004).« less

Interaction between Nbp35 and Cfd1 Proteins of Cytosolic Fe-S Cluster Assembly Reveals a Stable Complex Formation in Entamoeba histolytica

PubMed Central

Anwar, Shadab; Dikhit, Manas Ranjan; Singh, Krishn Pratap; Kar, Rajiv Kumar; Zaidi, Amir; Sahoo, Ganesh Chandra; Roy, Awadh Kishore; Nozaki, Tomoyoshi; Das, Pradeep; Ali, Vahab

2014-01-01

Iron-Sulfur (Fe-S) proteins are involved in many biological functions such as electron transport, photosynthesis, regulation of gene expression and enzymatic activities. Biosynthesis and transfer of Fe-S clusters depend on Fe-S clusters assembly processes such as ISC, SUF, NIF, and CIA systems. Unlike other eukaryotes which possess ISC and CIA systems, amitochondriate Entamoeba histolytica has retained NIF & CIA systems for Fe-S cluster assembly in the cytosol. In the present study, we have elucidated interaction between two proteins of E. histolytica CIA system, Cytosolic Fe-S cluster deficient 1 (Cfd1) protein and Nucleotide binding protein 35 (Nbp35). In-silico analysis showed that structural regions ranging from amino acid residues (P33-K35, G131-V135 and I147-E151) of Nbp35 and (G5-V6, M34-D39 and G46-A52) of Cfd1 are involved in the formation of protein-protein complex. Furthermore, Molecular dynamic (MD) simulations study suggested that hydrophobic forces surpass over hydrophilic forces between Nbp35 and Cfd1 and Van-der-Waal interaction plays crucial role in the formation of stable complex. Both proteins were separately cloned, expressed as recombinant fusion proteins in E. coli and purified to homogeneity by affinity column chromatography. Physical interaction between Nbp35 and Cfd1 proteins was confirmed in vitro by co-purification of recombinant Nbp35 with thrombin digested Cfd1 and in vivo by pull down assay and immunoprecipitation. The insilico, in vitro as well as in vivo results prove a stable interaction between these two proteins, supporting the possibility of its involvement in Fe-S cluster transfer to target apo-proteins through CIA machinery in E. histolytica. Our study indicates that initial synthesis of a Fe-S precursor in mitochondria is not necessary for the formation of Cfd1-Nbp35 complex. Thus, Cfd1 and Nbp35 with the help of cytosolic NifS and NifU proteins can participate in the maturation of non-mitosomal Fe-S proteins without any apparent assistance of mitosomes. PMID:25271645

Stochastic dynamics of time correlation in complex systems with discrete time

NASA Astrophysics Data System (ADS)

Yulmetyev, Renat; Hänggi, Peter; Gafarov, Fail

2000-11-01

In this paper we present the concept of description of random processes in complex systems with discrete time. It involves the description of kinetics of discrete processes by means of the chain of finite-difference non-Markov equations for time correlation functions (TCFs). We have introduced the dynamic (time dependent) information Shannon entropy Si(t) where i=0,1,2,3,..., as an information measure of stochastic dynamics of time correlation (i=0) and time memory (i=1,2,3,...). The set of functions Si(t) constitute the quantitative measure of time correlation disorder (i=0) and time memory disorder (i=1,2,3,...) in complex system. The theory developed started from the careful analysis of time correlation involving dynamics of vectors set of various chaotic states. We examine two stochastic processes involving the creation and annihilation of time correlation (or time memory) in details. We carry out the analysis of vectors' dynamics employing finite-difference equations for random variables and the evolution operator describing their natural motion. The existence of TCF results in the construction of the set of projection operators by the usage of scalar product operation. Harnessing the infinite set of orthogonal dynamic random variables on a basis of Gram-Shmidt orthogonalization procedure tends to creation of infinite chain of finite-difference non-Markov kinetic equations for discrete TCFs and memory functions (MFs). The solution of the equations above thereof brings to the recurrence relations between the TCF and MF of senior and junior orders. This offers new opportunities for detecting the frequency spectra of power of entropy function Si(t) for time correlation (i=0) and time memory (i=1,2,3,...). The results obtained offer considerable scope for attack on stochastic dynamics of discrete random processes in a complex systems. Application of this technique on the analysis of stochastic dynamics of RR intervals from human ECG's shows convincing evidence for a non-Markovian phenomemena associated with a peculiarities in short- and long-range scaling. This method may be of use in distinguishing healthy from pathologic data sets based in differences in these non-Markovian properties.

Interaction between Nbp35 and Cfd1 proteins of cytosolic Fe-S cluster assembly reveals a stable complex formation in Entamoeba histolytica.

PubMed

Anwar, Shadab; Dikhit, Manas Ranjan; Singh, Krishn Pratap; Kar, Rajiv Kumar; Zaidi, Amir; Sahoo, Ganesh Chandra; Roy, Awadh Kishore; Nozaki, Tomoyoshi; Das, Pradeep; Ali, Vahab

2014-01-01

Iron-Sulfur (Fe-S) proteins are involved in many biological functions such as electron transport, photosynthesis, regulation of gene expression and enzymatic activities. Biosynthesis and transfer of Fe-S clusters depend on Fe-S clusters assembly processes such as ISC, SUF, NIF, and CIA systems. Unlike other eukaryotes which possess ISC and CIA systems, amitochondriate Entamoeba histolytica has retained NIF & CIA systems for Fe-S cluster assembly in the cytosol. In the present study, we have elucidated interaction between two proteins of E. histolytica CIA system, Cytosolic Fe-S cluster deficient 1 (Cfd1) protein and Nucleotide binding protein 35 (Nbp35). In-silico analysis showed that structural regions ranging from amino acid residues (P33-K35, G131-V135 and I147-E151) of Nbp35 and (G5-V6, M34-D39 and G46-A52) of Cfd1 are involved in the formation of protein-protein complex. Furthermore, Molecular dynamic (MD) simulations study suggested that hydrophobic forces surpass over hydrophilic forces between Nbp35 and Cfd1 and Van-der-Waal interaction plays crucial role in the formation of stable complex. Both proteins were separately cloned, expressed as recombinant fusion proteins in E. coli and purified to homogeneity by affinity column chromatography. Physical interaction between Nbp35 and Cfd1 proteins was confirmed in vitro by co-purification of recombinant Nbp35 with thrombin digested Cfd1 and in vivo by pull down assay and immunoprecipitation. The insilico, in vitro as well as in vivo results prove a stable interaction between these two proteins, supporting the possibility of its involvement in Fe-S cluster transfer to target apo-proteins through CIA machinery in E. histolytica. Our study indicates that initial synthesis of a Fe-S precursor in mitochondria is not necessary for the formation of Cfd1-Nbp35 complex. Thus, Cfd1 and Nbp35 with the help of cytosolic NifS and NifU proteins can participate in the maturation of non-mitosomal Fe-S proteins without any apparent assistance of mitosomes.

Inverse modeling with RZWQM2 to predict water quality

USDA-ARS?s Scientific Manuscript database

Agricultural systems models such as RZWQM2 are complex and have numerous parameters that are unknown and difficult to estimate. Inverse modeling provides an objective statistical basis for calibration that involves simultaneous adjustment of model parameters and yields parameter confidence intervals...

Development of a Methodology for Incorporating FESWMS-2DH Results

DOT National Transportation Integrated Search

2000-05-01

This study presents the analysis of a complex flow system that contains two roadways with multiple openings: US Highway 75 and the Southeast Kansas Corridor. Typical analyses of floodplains at such sites involve the use of the one-dimensional backwat...

Development of Civic Engagement: Theoretical and Methodological Issues

ERIC Educational Resources Information Center

Lerner, Richard M.; Wang, Jun; Champine, Robey B.; Warren, Daniel J. A.; Erickson, Karl

2014-01-01

Within contemporary developmental science, models derived from relational developmental systems (RDS) metatheory emphasize that the basic process of human development involves mutually-influential relations, termed developmental regulations, between the developing individual and his or her complex and changing physical, social, and cultural…

Applied statistics in agricultural, biological, and environmental sciences.

USDA-ARS?s Scientific Manuscript database

Agronomic research often involves measurement and collection of multiple response variables in an effort to understand the more complex nature of the system being studied. Multivariate statistical methods encompass the simultaneous analysis of all random variables measured on each experimental or s...

The computational challenges of Earth-system science.

PubMed

O'Neill, Alan; Steenman-Clark, Lois

2002-06-15

The Earth system--comprising atmosphere, ocean, land, cryosphere and biosphere--is an immensely complex system, involving processes and interactions on a wide range of space- and time-scales. To understand and predict the evolution of the Earth system is one of the greatest challenges of modern science, with success likely to bring enormous societal benefits. High-performance computing, along with the wealth of new observational data, is revolutionizing our ability to simulate the Earth system with computer models that link the different components of the system together. There are, however, considerable scientific and technical challenges to be overcome. This paper will consider four of them: complexity, spatial resolution, inherent uncertainty and time-scales. Meeting these challenges requires a significant increase in the power of high-performance computers. The benefits of being able to make reliable predictions about the evolution of the Earth system should, on their own, amply repay this investment.

Modelling and simulating a crisis management system: an organisational perspective

NASA Astrophysics Data System (ADS)

Chaawa, Mohamed; Thabet, Inès; Hanachi, Chihab; Ben Said, Lamjed

2017-04-01

Crises are complex situations due to the dynamism of the environment, its unpredictability and the complexity of the interactions among several different and autonomous involved organisations. In such a context, establishing an organisational view as well as structuring organisations' communications and their functioning is a crucial requirement. In this article, we propose a multi-agent organisational model (OM) to abstract, simulate and analyse a crisis management system (CMS). The objective is to evaluate the CMS from an organisational view, to assess its strength as well as its weakness and to provide deciders with some recommendations for a more flexible and reactive CMS. The proposed OM is illustrated through a real case study: a snowstorm in a Tunisian region. More precisely, we made the following contribution: firstly, we provide an environmental model that identifies the concepts involved in the crisis. Then, we define a role model that copes with the involved actors. In addition, we specify the organisational structure and the interaction model that rule communications and structure actors' functioning. Those models, built following the GAIA methodology, abstract the CMS from an organisational perspective. Finally, we implemented a customisable multi-agent simulator based on the Janus platform to analyse, through several performed simulations, the organisational model.

Interaction surface and topology of Get3-Get4-Get5 protein complex, involved in targeting tail-anchored proteins to endoplasmic reticulum.

PubMed

Chang, Yi-Wei; Lin, Tai-Wen; Li, Yi-Chuan; Huang, Yu-Shan; Sun, Yuh-Ju; Hsiao, Chwan-Deng

2012-02-10

Recent work has uncovered the "GET system," which is responsible for endoplasmic reticulum targeting of tail-anchored proteins. Although structural information and the individual roles of most components of this system have been defined, the interactions and interplay between them remain to be elucidated. Here, we investigated the interactions between Get3 and the Get4-Get5 complex from Saccharomyces cerevisiae. We show that Get3 interacts with Get4-Get5 via an interface dominated by electrostatic forces. Using isothermal titration calorimetry and small-angle x-ray scattering, we further demonstrate that the Get3 homodimer interacts with two copies of the Get4-Get5 complex to form an extended conformation in solution.

Living supramolecular polymerization achieved by collaborative assembly of platinum(II) complexes and block copolymers

PubMed Central

Zhang, Kaka; Yeung, Margaret Ching-Lam; Leung, Sammual Yu-Lut; Yam, Vivian Wing-Wah

2017-01-01

An important feature of biological systems to achieve complexity and precision is the involvement of multiple components where each component plays its own role and collaborates with other components. Mimicking this, we report living supramolecular polymerization achieved by collaborative assembly of two structurally dissimilar components, that is, platinum(II) complexes and poly(ethylene glycol)-b-poly(acrylic acid) (PEG-b-PAA). The PAA blocks neutralize the charges of the platinum(II) complexes, with the noncovalent metal–metal and π–π interactions directing the longitudinal growth of the platinum(II) complexes into 1D crystalline nanostructures, and the PEG blocks inhibiting the transverse growth of the platinum(II) complexes and providing the whole system with excellent solubility. The ends of the 1D crystalline nanostructures have been found to be active during the assembly and remain active after the assembly. One-dimensional segmented nanostructures with heterojunctions have been produced by sequential growth of two types of platinum(II) complexes. The PAA blocks act as adapters at the heterojunctions for lattice matching between chemically and crystallographically different platinum(II) complexes, achieving heterojunctions with a lattice mismatch as large as 21%. PMID:29078381

Miniature wireless recording and stimulation system for rodent behavioural testing

NASA Astrophysics Data System (ADS)

Pinnell, R. C.; Dempster, J.; Pratt, J.

2015-12-01

Objective. Elucidation of neural activity underpinning rodent behaviour has traditionally been hampered by the use of tethered systems and human involvement. Furthermore the combination of deep-brain stimulation (DBS) and various neural recording modalities can lead to complex and time-consuming laboratory setups. For studies of this type, novel tools are required to drive forward this research. Approach. A miniature wireless system weighing 8.5 g (including battery) was developed for rodent use that combined multichannel DBS and local-field potential (LFP) recordings. Its performance was verified in a working memory task that involved 4-channel fronto-hippocampal LFP recording and bilateral constant-current fimbria-fornix DBS. The system was synchronised with video-tracking for extraction of LFP at discrete task phases, and DBS was activated intermittently at discrete phases of the task. Main results. In addition to having a fast set-up time, the system could reliably transmit continuous LFP at over 8 hours across 3-5 m distances. During the working memory task, LFP pertaining to discrete task phases was extracted and compared with well-known neural correlates of active exploratory behaviour in rodents. DBS could be wirelessly activated/deactivated at any part of the experiment during EEG recording and transmission, allowing for a seamless integration of this modality. Significance. The wireless system combines a small size with a level of robustness and versatility that can greatly simplify rodent behavioural experiments involving EEG recording and DBS. Designed for versatility and simplicity, the small size and low-cost of the system and its receiver allow for enhanced portability, fast experimental setup times, and pave the way for integration with more complex behaviour.

Large-scale study of the interactions between proteins involved in type IV pilus biology in Neisseria meningitidis: characterization of a subcomplex involved in pilus assembly.

PubMed

Georgiadou, Michaella; Castagnini, Marta; Karimova, Gouzel; Ladant, Daniel; Pelicic, Vladimir

2012-06-01

The functionally versatile type IV pili (Tfp) are one of the most widespread virulence factors in bacteria. However, despite generating much research interest for decades, the molecular mechanisms underpinning the various aspects of Tfp biology remain poorly understood, mainly because of the complexity of the system. In the human pathogen Neisseria meningitidis for example, 23 proteins are dedicated to Tfp biology, 15 of which are essential for pilus biogenesis. One of the important gaps in our knowledge concerns the topology of this multiprotein machinery. Here we have used a bacterial two-hybrid system to identify and quantify the interactions between 11 Pil proteins from N. meningitidis. We identified 20 different binary interactions, many of which are novel. This represents the most complex interaction network between Pil proteins reported to date and indicates, among other things, that PilE, PilM, PilN and PilO, which are involved in pilus assembly, indeed interact. We focused our efforts on this subset of proteins and used a battery of assays to determine the membrane topology of PilN and PilO, map the interaction domains between PilE, PilM, PilN and PilO, and show that a widely conserved N-terminal motif in PilN is essential for both PilM-PilN interactions and pilus assembly. Finally, we show that PilP (another protein involved in pilus assembly) forms a complex with PilM, PilN and PilO. Taken together, these findings have numerous implications for understanding Tfp biology and provide a useful blueprint for future studies. © 2012 Blackwell Publishing Ltd.

Agent-based modeling of endotoxin-induced acute inflammatory response in human blood leukocytes.

PubMed

Dong, Xu; Foteinou, Panagiota T; Calvano, Steven E; Lowry, Stephen F; Androulakis, Ioannis P

2010-02-18

Inflammation is a highly complex biological response evoked by many stimuli. A persistent challenge in modeling this dynamic process has been the (nonlinear) nature of the response that precludes the single-variable assumption. Systems-based approaches offer a promising possibility for understanding inflammation in its homeostatic context. In order to study the underlying complexity of the acute inflammatory response, an agent-based framework is developed that models the emerging host response as the outcome of orchestrated interactions associated with intricate signaling cascades and intercellular immune system interactions. An agent-based modeling (ABM) framework is proposed to study the nonlinear dynamics of acute human inflammation. The model is implemented using NetLogo software. Interacting agents involve either inflammation-specific molecules or cells essential for the propagation of the inflammatory reaction across the system. Spatial orientation of molecule interactions involved in signaling cascades coupled with the cellular heterogeneity are further taken into account. The proposed in silico model is evaluated through its ability to successfully reproduce a self-limited inflammatory response as well as a series of scenarios indicative of the nonlinear dynamics of the response. Such scenarios involve either a persistent (non)infectious response or innate immune tolerance and potentiation effects followed by perturbations in intracellular signaling molecules and cascades. The ABM framework developed in this study provides insight on the stochastic interactions of the mediators involved in the propagation of endotoxin signaling at the cellular response level. The simulation results are in accordance with our prior research effort associated with the development of deterministic human inflammation models that include transcriptional dynamics, signaling, and physiological components. The hypothetical scenarios explored in this study would potentially improve our understanding of how manipulating the behavior of the molecular species could manifest into emergent behavior of the overall system.

Structural Information Inference from Lanthanoid Complexing Systems: Photoluminescence Studies on Isolated Ions

NASA Astrophysics Data System (ADS)

Greisch, Jean Francois; Harding, Michael E.; Chmela, Jiri; Klopper, Willem M.; Schooss, Detlef; Kappes, Manfred M.

2016-06-01

The application of lanthanoid complexes ranges from photovoltaics and light-emitting diodes to quantum memories and biological assays. Rationalization of their design requires a thorough understanding of intramolecular processes such as energy transfer, charge transfer, and non-radiative decay involving their subunits. Characterization of the excited states of such complexes considerably benefits from mass spectrometric methods since the associated optical transitions and processes are strongly affected by stoichiometry, symmetry, and overall charge state. We report herein spectroscopic measurements on ensembles of ions trapped in the gas phase and soft-landed in neon matrices. Their interpretation is considerably facilitated by direct comparison with computations. The combination of energy- and time-resolved measurements on isolated species with density functional as well as ligand-field and Franck-Condon computations enables us to infer structural as well as dynamical information about the species studied. The approach is first illustrated for sets of model lanthanoid complexes whose structure and electronic properties are systematically varied via the substitution of one component (lanthanoid or alkali,alkali-earth ion): (i) systematic dependence of ligand-centered phosphorescence on the lanthanoid(III) promotion energy and its impact on sensitization, and (ii) structural changes induced by the substitution of alkali or alkali-earth ions in relation with structures inferred using ion mobility spectroscopy. The temperature dependence of sensitization is briefly discussed. The focus is then shifted to measurements involving europium complexes with doxycycline an antibiotic of the tetracycline family. Besides discussing the complexes' structural and electronic features, we report on their use to monitor enzymatic processes involving hydrogen peroxide or biologically relevant molecules such as adenosine triphosphate (ATP).

The behavior and importance of lactic acid complexation in Talspeak extraction systems

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

Grimes, Travis S.; Nilsson, Mikael; Nash, Kenneth L.

2008-07-01

Advanced partitioning of spent nuclear fuel in the UREX +la process relies on the TALSPEAK process for separation of fission-product lanthanides from trivalent actinides. The classic TALSPEAK utilizes an aqueous medium of both lactic acid and diethylenetriaminepentaacetic acid and the extraction reagent di(2-ethylhexyl)phosphoric acid in an aromatic diluent. In this study, the specific role of lactic acid and the complexes involved in the extraction of the trivalent actinides and lanthanides have been investigated using {sup 14}C-labeled lactic acid. Our results show that lactic acid partitions between the phases in a complex fashion. (authors)

Advancing Sensor Technology for Aerospace Propulsion

NASA Technical Reports Server (NTRS)

Figueroa, Fernando; Mercer, Carolyn R.

2002-01-01

NASA's Stennis Space Center (SSC) and Glenn Research Center (GRC) participate in the development of technologies for propulsion testing and propulsion applications in air and space transportation. Future transportation systems and the test facilities needed to develop and sustain them are becoming increasingly complex. Sensor technology is a fundamental pillar that makes possible development of complex systems that must operate in automatic mode (closed loop systems), or even in assisted-autonomous mode (highly self-sufficient systems such as planetary exploration spacecraft). Hence, a great deal of effort is dedicated to develop new sensors and related technologies to be used in research facilities, test facilities, and in vehicles and equipment. This paper describes sensor technologies being developed and in use at SSC and GRC, including new technologies in integrated health management involving sensors, components, processes, and vehicles.

From Paper to PDA: Design and Evaluation of a Clinical Ward Instruction on a Mobile Device

NASA Astrophysics Data System (ADS)

Kanstrup, Anne Marie; Stage, Jan

Mobile devices with small screens and minimal facilities for interaction are increasingly being used in complex human activities for accessing and processing information, while the user is moving. This paper presents a case study of the design and evaluation of a mobile system, which involved transformation of complex text and tables to digital format on a PDA. The application domain was an emergency medical ward, and the user group was junior registrars. We designed a PDA-based system for accessing information, focusing on the ward instruction, implemented a prototype and evaluated it for usability and utility. The evaluation results indicate significant problems in the interaction with the system as well as the extent to which the system is useful for junior registrars in their daily work.

Family impact of assistive technology scale: development of a measurement scale for parents of children with complex communication needs.

PubMed

Delarosa, Elizabeth; Horner, Stephanie; Eisenberg, Casey; Ball, Laura; Renzoni, Anne Marie; Ryan, Stephen E

2012-09-01

Young people use augmentative and alternative communication (AAC) systems to meet their everyday communication needs. However, the successful integration of an AAC system into a child's life requires strong commitment and continuous support from parents and other family members. This article describes the development and evaluation of the Family Impact of Assistive Technology Scale for AAC Systems - a parent-report questionnaire intended to detect the impact of AAC systems on the lives of children with complex communication needs and their families. The study involved 179 parents and clinical experts to test the content and face validities of the questionnaire, demonstrate its internal reliability and stability over time, and estimate its convergent construct validity when compared to a standardized measure of family impact.

Transcription factors involved in drought tolerance and their possible role in developing drought tolerant cultivars with emphasis on wheat (Triticum aestivum L.).

PubMed

Gahlaut, Vijay; Jaiswal, Vandana; Kumar, Anuj; Gupta, Pushpendra Kumar

2016-11-01

TFs involved in drought tolerance in plants may be utilized in future for developing drought tolerant cultivars of wheat and some other crops. Plants have developed a fairly complex stress response system to deal with drought and other abiotic stresses. These response systems often make use of transcription factors (TFs); a gene encoding a specific TF together with -its target genes constitute a regulon, and take part in signal transduction to activate/silence genes involved in response to drought. Since, five specific families of TFs (out of >80 known families of TFs) have gained widespread attention on account of their significant role in drought tolerance in plants, TFs and regulons belonging to these five multi-gene families (AP2/EREBP, bZIP, MYB/MYC, NAC and WRKY) have been described and their role in improving drought tolerance discussed in this brief review. These TFs often undergo reversible phosphorylation to perform their function, and are also involved in complex networks. Therefore, some details about reversible phosphorylation of TFs by different protein kinases/phosphatases and the co-regulatory networks, which involve either only TFs or TFs with miRNAs, have also been discussed. Literature on transgenics involving genes encoding TFs and that on QTLs and markers associated with TF genes involved in drought tolerance has also been reviewed. Throughout the review, there is a major emphasis on wheat as an important crop, although examples from the model cereal rice (sometimes maize also), and the model plant Arabidopsis have also been used. This knowledge base may eventually allow the use of TF genes for development of drought tolerant cultivars, particularly in wheat.

Sustainable development goals for global health: facilitating good governance in a complex environment.

PubMed

Haffeld, Just

2013-11-01

Increasing complexity is following in the wake of rampant globalization. Thus, the discussion about Sustainable Development Goals (SDGs) requires new thinking that departs from a critique of current policy tools in exploration of a complexity-friendly approach. This article argues that potential SDGs should: treat stakeholders, like states, business and civil society actors, as agents on different aggregate levels of networks; incorporate good governance processes that facilitate early involvement of relevant resources, as well as equitable participation, consultative processes, and regular policy and programme implementation reviews; anchor adoption and enforcement of such rules to democratic processes in accountable organizations; and include comprehensive systems evaluations, including procedural indicators. A global framework convention for health could be a suitable instrument for handling some of the challenges related to the governance of a complex environment. It could structure and legitimize government involvement, engage stakeholders, arrange deliberation and decision-making processes with due participation and regular policy review, and define minimum standards for health services. A monitoring scheme could ensure that agents in networks comply according to whole-systems targets, locally defined outcome indicators, and process indicators, thus resolving the paradox of government control vs. local policy space. A convention could thus exploit the energy created in the encounter between civil society, international organizations and national authorities. Copyright © 2013 Reproductive Health Matters. Published by Elsevier Ltd. All rights reserved.

A programming environment for distributed complex computing. An overview of the Framework for Interdisciplinary Design Optimization (FIDO) project. NASA Langley TOPS exhibit H120b

NASA Technical Reports Server (NTRS)

Townsend, James C.; Weston, Robert P.; Eidson, Thomas M.

1993-01-01

The Framework for Interdisciplinary Design Optimization (FIDO) is a general programming environment for automating the distribution of complex computing tasks over a networked system of heterogeneous computers. For example, instead of manually passing a complex design problem between its diverse specialty disciplines, the FIDO system provides for automatic interactions between the discipline tasks and facilitates their communications. The FIDO system networks all the computers involved into a distributed heterogeneous computing system, so they have access to centralized data and can work on their parts of the total computation simultaneously in parallel whenever possible. Thus, each computational task can be done by the most appropriate computer. Results can be viewed as they are produced and variables changed manually for steering the process. The software is modular in order to ease migration to new problems: different codes can be substituted for each of the current code modules with little or no effect on the others. The potential for commercial use of FIDO rests in the capability it provides for automatically coordinating diverse computations on a networked system of workstations and computers. For example, FIDO could provide the coordination required for the design of vehicles or electronics or for modeling complex systems.

Automated dredging and disposal alternatives management system (ADDAMS). Environmental effects of dredging. Technical note

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

NONE

This technical note describes the current capabilities and availability of the Automated Dredging and Disposal Alternatives Management System (ADDAMS). The technical note replaces the earlier Technical Note EEDP-06-12, which should be discarded. Planning, design, and management of dredging and dredged material disposal projects often require complex or tedious calculations or involve complex decision-making criteria. In addition, the evaluations often must be done for several disposal alternatives or disposal sites. ADDAMS is a personal computer (PC)-based system developed to assist in making such evaluations in a timely manner. ADDAMS contains a collection of computer programs (applications) designed to assist in managingmore » dredging projects. This technical note describes the system, currently available applications, mechanisms for acquiring and running the system, and provisions for revision and expansion.« less

A Distributed Value of Information (VoI)-Based Approach for Mission-Adaptive Context-Aware Information Management and Presentation

DTIC Science & Technology

2016-05-16

metrics involve regulating automation of complex systems , such as aircraft .12 Additionally, adaptive management of content in user interfaces has also...both the user and environmental context would aid in deciding how to present the information to the Warfighter. The prototype system currently...positioning system , and rate sensors can provide user - specific context to disambiguate physiologic data. The consumer “quantified self” market has driven

Cryo-EM of dynamic protein complexes in eukaryotic DNA replication.

PubMed

Sun, Jingchuan; Yuan, Zuanning; Bai, Lin; Li, Huilin

2017-01-01

DNA replication in Eukaryotes is a highly dynamic process that involves several dozens of proteins. Some of these proteins form stable complexes that are amenable to high-resolution structure determination by cryo-EM, thanks to the recent advent of the direct electron detector and powerful image analysis algorithm. But many of these proteins associate only transiently and flexibly, precluding traditional biochemical purification. We found that direct mixing of the component proteins followed by 2D and 3D image sorting can capture some very weakly interacting complexes. Even at 2D average level and at low resolution, EM images of these flexible complexes can provide important biological insights. It is often necessary to positively identify the feature-of-interest in a low resolution EM structure. We found that systematically fusing or inserting maltose binding protein (MBP) to selected proteins is highly effective in these situations. In this chapter, we describe the EM studies of several protein complexes involved in the eukaryotic DNA replication over the past decade or so. We suggest that some of the approaches used in these studies may be applicable to structural analysis of other biological systems. © 2016 The Protein Society.

Mi2, an auto-antigen for dermatomyositis, is an ATP-dependent nucleosome remodeling factor.

PubMed

Wang, H B; Zhang, Y

2001-06-15

Dynamic changes in chromatin structure play an important role in transcription regulation. Recent studies have revealed two mechanisms that alter chromatin structure. One involves ATP-dependent chromatin remodeling, and the other involves acetylation of the core histone tails. We have previously purified and characterized a multi-subunit protein complex, NuRD, which possesses both nucleosome remodeling and histone deacetylase activities. Despite extensive biochemical characterization of the complex, little is known about the functions of its individual components. In this study, we focused on Mi2, a component of the NuRD complex. We found that, similar to the native NuRD complex, recombinant Mi2 is a DNA-dependent, nucleosome-stimulated ATPase. Kinetic analysis of the ATP hydrolysis reaction indicated that the differential stimulation of the Mi2 ATPase by DNA and nucleosomes were primarily due to their differential effects on the turnover number of the reaction. Furthermore, we demonstrated that recombinant Mi2 is an efficient nucleosome remodeling factor when compared to that of the native NuRD complex. Our results define the biochemical function of Mi2 and set the stage for understanding the mechanism of nucleosome remodeling in a defined reconstituted system.

Mi2, an auto-antigen for dermatomyositis, is an ATP-dependent nucleosome remodeling factor

PubMed Central

Wang, Heng-Bin; Zhang, Yi

2001-01-01

Dynamic changes in chromatin structure play an important role in transcription regulation. Recent studies have revealed two mechanisms that alter chromatin structure. One involves ATP-dependent chromatin remodeling, and the other involves acetylation of the core histone tails. We have previously purified and characterized a multi-subunit protein complex, NuRD, which possesses both nucleosome remodeling and histone deacetylase activities. Despite extensive biochemical characterization of the complex, little is known about the functions of its individual components. In this study, we focused on Mi2, a component of the NuRD complex. We found that, similar to the native NuRD complex, recombinant Mi2 is a DNA-dependent, nucleosome-stimulated ATPase. Kinetic analysis of the ATP hydrolysis reaction indicated that the differential stimulation of the Mi2 ATPase by DNA and nucleosomes were primarily due to their differential effects on the turnover number of the reaction. Furthermore, we demonstrated that recombinant Mi2 is an efficient nucleosome remodeling factor when compared to that of the native NuRD complex. Our results define the biochemical function of Mi2 and set the stage for understanding the mechanism of nucleosome remodeling in a defined reconstituted system. PMID:11410659

Minimum Control Requirements for Advanced Life Support Systems

NASA Technical Reports Server (NTRS)

Boulange, Richard; Jones, Harry; Jones, Harry

2002-01-01

Advanced control technologies are not necessary for the safe, reliable and continuous operation of Advanced Life Support (ALS) systems. ALS systems can and are adequately controlled by simple, reliable, low-level methodologies and algorithms. The automation provided by advanced control technologies is claimed to decrease system mass and necessary crew time by reducing buffer size and minimizing crew involvement. In truth, these approaches increase control system complexity without clearly demonstrating an increase in reliability across the ALS system. Unless these systems are as reliable as the hardware they control, there is no savings to be had. A baseline ALS system is presented with the minimal control system required for its continuous safe reliable operation. This baseline control system uses simple algorithms and scheduling methodologies and relies on human intervention only in the event of failure of the redundant backup equipment. This ALS system architecture is designed for reliable operation, with minimal components and minimal control system complexity. The fundamental design precept followed is "If it isn't there, it can't fail".

A complex systems approach to constructing better models for managing financial markets and the economy

NASA Astrophysics Data System (ADS)

Farmer, J. Doyne; Gallegati, M.; Hommes, C.; Kirman, A.; Ormerod, P.; Cincotti, S.; Sanchez, A.; Helbing, D.

2012-11-01

We outline a vision for an ambitious program to understand the economy and financial markets as a complex evolving system of coupled networks of interacting agents. This is a completely different vision from that currently used in most economic models. This view implies new challenges and opportunities for policy and managing economic crises. The dynamics of such models inherently involve sudden and sometimes dramatic changes of state. Further, the tools and approaches we use emphasize the analysis of crises rather than of calm periods. In this they respond directly to the calls of Governors Bernanke and Trichet for new approaches to macroeconomic modelling.

Endocannabinod Signal Dysregulation in Autism Spectrum Disorders: A Correlation Link between Inflammatory State and Neuro-Immune Alterations

PubMed Central

Brigida, Anna Lisa; Schultz, Stephen; Cascone, Mariana; Antonucci, Nicola; Siniscalco, Dario

2017-01-01

Several studies highlight a key involvement of endocannabinoid (EC) system in autism pathophysiology. The EC system is a complex network of lipid signaling pathways comprised of arachidonic acid-derived compounds (anandamide, AEA) and 2-arachidonoyl glycerol (2-AG), their G-protein-coupled receptors (cannabinoid receptors CB1 and CB2) and the associated enzymes. In addition to autism, the EC system is also involved in several other psychiatric disorders (i.e., anxiety, major depression, bipolar disorder and schizophrenia). This system is a key regulator of metabolic and cellular pathways involved in autism, such as food intake, energy metabolism and immune system control. Early studies in autism animal models have demonstrated alterations in the brain’s EC system. Autism is also characterized by immune system dysregulation. This alteration includes differential monocyte and macrophage responses, and abnormal cytokine and T cell levels. EC system dysfunction in a monocyte and macrophagic cellular model of autism has been demonstrated by showing that the mRNA and protein for CB2 receptor and EC enzymes were significantly dysregulated, further indicating the involvement of the EC system in autism-associated immunological disruptions. Taken together, these new findings offer a novel perspective in autism research and indicate that the EC system could represent a novel target option for autism pharmacotherapy. PMID:28671614

Stochastic simulation of multiscale complex systems with PISKaS: A rule-based approach.

PubMed

Perez-Acle, Tomas; Fuenzalida, Ignacio; Martin, Alberto J M; Santibañez, Rodrigo; Avaria, Rodrigo; Bernardin, Alejandro; Bustos, Alvaro M; Garrido, Daniel; Dushoff, Jonathan; Liu, James H

2018-03-29

Computational simulation is a widely employed methodology to study the dynamic behavior of complex systems. Although common approaches are based either on ordinary differential equations or stochastic differential equations, these techniques make several assumptions which, when it comes to biological processes, could often lead to unrealistic models. Among others, model approaches based on differential equations entangle kinetics and causality, failing when complexity increases, separating knowledge from models, and assuming that the average behavior of the population encompasses any individual deviation. To overcome these limitations, simulations based on the Stochastic Simulation Algorithm (SSA) appear as a suitable approach to model complex biological systems. In this work, we review three different models executed in PISKaS: a rule-based framework to produce multiscale stochastic simulations of complex systems. These models span multiple time and spatial scales ranging from gene regulation up to Game Theory. In the first example, we describe a model of the core regulatory network of gene expression in Escherichia coli highlighting the continuous model improvement capacities of PISKaS. The second example describes a hypothetical outbreak of the Ebola virus occurring in a compartmentalized environment resembling cities and highways. Finally, in the last example, we illustrate a stochastic model for the prisoner's dilemma; a common approach from social sciences describing complex interactions involving trust within human populations. As whole, these models demonstrate the capabilities of PISKaS providing fertile scenarios where to explore the dynamics of complex systems. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Equilibrium Speciation of Select Lanthanides in the Presence of Acidic Ligands in Homo- and Heterogeneous Solutions

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

Robinson, Troy A

2011-08-01

This dissertation explores lanthanide speciation in liquid solution systems related to separation schemes involving the acidic ligands: bis(2-ethylhexyl) phosphoric acid (HDEHP), lactate, and 8-hydroxyquinoline. Equilibrium speciation of neodymium (Nd 3+), sodium (Na+), HDEHP, water, and lactate in the TALSPEAK liquid-liquid extraction system was explored under varied Nd 3+ loading of HDEHP in the organic phase and through extraction from aqueous HCl and lactate media. System speciation was probed through vapor pressure osmometry, visible and Fourier Transform Infrared (FTIR) spectroscopy, 22Na and 13C labeled lactate radiotracer distribution measurements, Karl Fischer titrations, and equilibrium pH measurements. Distribution of Nd 3+, Na +,more » lactate, and equilibrium pH were modeled using the SXLSQI software to obtain logKNd and logKNa extraction constants under selected conditions. Results showed that high Nd 3+ loading of the HDEHP led to Nd 3+ speciation that departs from the ion exchange mechanism and includes formation of highly aggregated, polynuclear [NdLactate(DEHP) 2] x; (with x > 1). By substituting lanthanum (La 3+) for Nd 3+ in this system, NMR scoping experiments using 23Na, 31P nuclei and 13C labeled lactate were performed. Results indicated that this technique is sensitive to changes in system speciation, and that further experiments are warranted. In a homogeneous system representing the TALSPEAK aqueous phase, Lactate protonation behavior at various temperatures was characterized using a combination of potentiometric titration and modeling with the Hyperquad computer program. The temperature dependent deprotonation behavior of lactate showed little change with temperature at 2.0 M NaCl ionic strength. Cloud point extraction is a non-traditional separation technique that starts with a homogeneous phase that becomes heterogeneous by the micellization of surfactants through the increase of temperature. To better understand the behavior of europium (Eu 3+) and 8-hydroxyquinoline under cloud point extraction conditions, potentiometric and spectrophotometric titrations coupled with modeling with Hyperquad and SQUAD computer programs were performed to assess europium (Eu 3+) and 8-hydroxyquinoline speciation. Experiments in both water and a 1wt% Triton X-114/water mixed solvent were compared to understand the effect of Triton X-114 on the system speciation. Results indicated that increased solvation of 8-hydroxyquinoline by the mixed solvent lead to more stable complexes involving 8-hydroxyquinoline than in water, whereas competition between hydroxide and Triton X-114 for Eu 3+ led to lower stability hydrolysis complexes in the mixed solvent than in water. Lanthanide speciation is challenging due to the trivalent oxidation state that leads to multiple ligand complexes, including some mixed complexes. The complexity of the system demands well-designed and precise experiments that capture the nuances of the chemistry. This work increased the understanding of lanthanide speciation in the explored systems, but more work is required to produce a comprehensive understanding of the speciation involved.« less

SPATIAL VARIABILITY IN POLLUTANTS: IMPLICATIONS FOR EXPOSURE ASSESSMENT

EPA Science Inventory

The efforts to evaluate the value of improved exposure metrics on the ability to relate those metrics with outcomes in complex systems have met with varying degrees of success. This work describes the results of recent efforts, mostly involving air pollutants, to improve the sop...

32 CFR 806.4 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... INFORMATION ACT PROGRAM § 806.4 Definitions. (a) Electronic reading room (ERR). Rooms established on Internet... involved. The responsive records contain no (or limited) personal privacy information and do not come from a Privacy Act system of records. No time extensions are anticipated. (2) Complex requests take...

Field Scale Monitoring and Modeling of Water and Chemical Transfer in the Vadose Zone

USDA-ARS?s Scientific Manuscript database

Natural resource systems involve highly complex interactions of soil-plant-atmosphere-management components that are extremely difficult to quantitatively describe. Computer simulations for prediction and management of watersheds, water supply areas, and agricultural fields and farms have become inc...

GENE EXPRESSION PROFILES IN THE DEVELOPING RAT CEREBELLUM AND HIPPOCAMPUS

EPA Science Inventory

Development of the nervous system is a complex program, involving coordinated growth of axons and their targets. In rodents, rapid brain growth occurs during early postnatal development. At this time, several fundamental processes, such as dendritic and axonal outgrowth and the e...

Cable Television Interconnection.

ERIC Educational Resources Information Center

Cable Television Information Center, Washington, DC.

State and local governments have not been involved in the complexities of cable television interconnection issues in the past despite opportunities. Without their intervention, the result may well be a lack of concern for local public services. However, the entertainment and communications industries will interconnect cable systems without the…

Assessment of wastewater treatment alternatives for small communities: An analytic network process approach.

PubMed

Molinos-Senante, María; Gómez, Trinidad; Caballero, Rafael; Hernández-Sancho, Francesc; Sala-Garrido, Ramón

2015-11-01

The selection of the most appropriate wastewater treatment (WWT) technology is a complex problem since many alternatives are available and many criteria are involved in the decision-making process. To deal with this challenge, the analytic network process (ANP) is applied for the first time to rank a set of seven WWT technology set-ups for secondary treatment in small communities. A major advantage of ANP is that it incorporates interdependent relationships between elements. Results illustrated that extensive technologies, constructed wetlands and pond systems are the most preferred alternatives by WWT experts. The sensitivity analysis performed verified that the ranking of WWT alternatives is very stable since constructed wetlands are almost always placed in the first position. This paper showed that ANP analysis is suitable to deal with complex decision-making problems, such as the selection of the most appropriate WWT system contributing to better understand the multiple interdependences among elements involved in the assessment. Copyright © 2015 Elsevier B.V. All rights reserved.

Explicit solution techniques for impact with contact constraints

NASA Technical Reports Server (NTRS)

Mccarty, Robert E.

1993-01-01

Modern military aircraft transparency systems, windshields and canopies, are complex systems which must meet a large and rapidly growing number of requirements. Many of these transparency system requirements are conflicting, presenting difficult balances which must be achieved. One example of a challenging requirements balance or trade is shaping for stealth versus aircrew vision. The large number of requirements involved may be grouped in a variety of areas including man-machine interface; structural integration with the airframe; combat hazards; environmental exposures; and supportability. Some individual requirements by themselves pose very difficult, severely nonlinear analysis problems. One such complex problem is that associated with the dynamic structural response resulting from high energy bird impact. An improved analytical capability for soft-body impact simulation was developed.

Explicit solution techniques for impact with contact constraints

NASA Astrophysics Data System (ADS)

McCarty, Robert E.

1993-08-01

Modern military aircraft transparency systems, windshields and canopies, are complex systems which must meet a large and rapidly growing number of requirements. Many of these transparency system requirements are conflicting, presenting difficult balances which must be achieved. One example of a challenging requirements balance or trade is shaping for stealth versus aircrew vision. The large number of requirements involved may be grouped in a variety of areas including man-machine interface; structural integration with the airframe; combat hazards; environmental exposures; and supportability. Some individual requirements by themselves pose very difficult, severely nonlinear analysis problems. One such complex problem is that associated with the dynamic structural response resulting from high energy bird impact. An improved analytical capability for soft-body impact simulation was developed.

Low-complexity camera digital signal imaging for video document projection system

NASA Astrophysics Data System (ADS)

Hsia, Shih-Chang; Tsai, Po-Shien

2011-04-01

We present high-performance and low-complexity algorithms for real-time camera imaging applications. The main functions of the proposed camera digital signal processing (DSP) involve color interpolation, white balance, adaptive binary processing, auto gain control, and edge and color enhancement for video projection systems. A series of simulations demonstrate that the proposed method can achieve good image quality while keeping computation cost and memory requirements low. On the basis of the proposed algorithms, the cost-effective hardware core is developed using Verilog HDL. The prototype chip has been verified with one low-cost programmable device. The real-time camera system can achieve 1270 × 792 resolution with the combination of extra components and can demonstrate each DSP function.

Mapping complex traits as a dynamic system

PubMed Central

Sun, Lidan; Wu, Rongling

2017-01-01

Despite increasing emphasis on the genetic study of quantitative traits, we are still far from being able to chart a clear picture of their genetic architecture, given an inherent complexity involved in trait formation. A competing theory for studying such complex traits has emerged by viewing their phenotypic formation as a “system” in which a high-dimensional group of interconnected components act and interact across different levels of biological organization from molecules through cells to whole organisms. This system is initiated by a machinery of DNA sequences that regulate a cascade of biochemical pathways to synthesize endophenotypes and further assemble these endophenotypes toward the end-point phenotype in virtue of various developmental changes. This review focuses on a conceptual framework for genetic mapping of complex traits by which to delineate the underlying components, interactions and mechanisms that govern the system according to biological principles and understand how these components function synergistically under the control of quantitative trait loci (QTLs) to comprise a unified whole. This framework is built by a system of differential equations that quantifies how alterations of different components lead to the global change of trait development and function, and provides a quantitative and testable platform for assessing the multiscale interplay between QTLs and development. The method will enable geneticists to shed light on the genetic complexity of any biological system and predict, alter or engineer its physiological and pathological states. PMID:25772476

Using participatory action research in a community-based initiative addressing complex mental health needs.

PubMed

Knightbridge, Stephen M; King, Robert; Rolfe, Timothy J

2006-04-01

This paper describes the first phase of a larger project that utilizes participatory action research to examine complex mental health needs across an extensive group of stakeholders in the community. Within an objective qualitative analysis of focus group discussions the social ecological model is utilized to explore how integrative activities can be informed, planned and implemented across multiple elements and levels of a system. Seventy-one primary care workers, managers, policy-makers, consumers and carers from across the southern metropolitan and Gippsland regions of Victoria, Australia took part in seven focus groups. All groups responded to an identical set of focusing questions. Participants produced an explanatory model describing the service system, as it relates to people with complex needs, across the levels of social ecological analysis. Qualitative themes analysis identified four priority areas to be addressed in order to improve the system's capacity for working with complexity. These included: (i) system fragmentation; (ii) integrative case management practices; (iii) community attitudes; and (iv) money and resources. The emergent themes provide clues as to how complexity is constructed and interpreted across the system of involved agencies and interest groups. The implications these findings have for the development and evaluation of this community capacity-building project were examined from the perspective of constructing interventions that address both top-down and bottom-up processes.

White paper: A plan for cooperation between NASA and DARPA to establish a center for advanced architectures

NASA Technical Reports Server (NTRS)

Denning, P. J.; Adams, G. B., III; Brown, R. L.; Kanerva, P.; Leiner, B. M.; Raugh, M. R.

1986-01-01

Large, complex computer systems require many years of development. It is recognized that large scale systems are unlikely to be delivered in useful condition unless users are intimately involved throughout the design process. A mechanism is described that will involve users in the design of advanced computing systems and will accelerate the insertion of new systems into scientific research. This mechanism is embodied in a facility called the Center for Advanced Architectures (CAA). CAA would be a division of RIACS (Research Institute for Advanced Computer Science) and would receive its technical direction from a Scientific Advisory Board established by RIACS. The CAA described here is a possible implementation of a center envisaged in a proposed cooperation between NASA and DARPA.

A Study of the Concept and Implementation of the Lead Systems Integrator in Defense Acquisitions

DTIC Science & Technology

2007-12-01

equips itself to fight U.S. adversaries. The Army has recognized that it needs to transform itself to conduct “full spectrum operations” ( Fetterman and...mountains and jungles” ( Fetterman and Plushnik 2). The Army describes the program as the most complex acquisition in its history because it involves...considered to be two additional systems; thus, it is dubbed “14+1+1” ( Fetterman ). Figure 1 shows all the systems in the FCS. 21 Figure 1. FCS Systems

Regulation of Blood Pressure and Salt Homeostasis by Endothelin

PubMed Central

KOHAN, DONALD E.; ROSSI, NOREEN F.; INSCHO, EDWARD W.; POLLOCK, DAVID M.

2011-01-01

Endothelin (ET) peptides and their receptors are intimately involved in the physiological control of systemic blood pressure and body Na homeostasis, exerting these effects through alterations in a host of circulating and local factors. Hormonal systems affected by ET include natriuretic peptides, aldosterone, catecholamines, and angiotensin. ET also directly regulates cardiac output, central and peripheral nervous system activity, renal Na and water excretion, systemic vascular resistance, and venous capacitance. ET regulation of these systems is often complex, sometimes involving opposing actions depending on which receptor isoform is activated, which cells are affected, and what other prevailing factors exist. A detailed understanding of this system is important; disordered regulation of the ET system is strongly associated with hypertension and dysregulated extracellular fluid volume homeostasis. In addition, ET receptor antagonists are being increasingly used for the treatment of a variety of diseases; while demonstrating benefit, these agents also have adverse effects on fluid retention that may substantially limit their clinical utility. This review provides a detailed analysis of how the ET system is involved in the control of blood pressure and Na homeostasis, focusing primarily on physiological regulation with some discussion of the role of the ET system in hypertension. PMID:21248162

The hippocampus is an integral part of the temporal limbic system during emotional processing. Comment on "The quartet theory of human emotions: An integrative and neurofunctional model" by S. Koelsch et al.

NASA Astrophysics Data System (ADS)

Trost, Wiebke; Frühholz, Sascha

2015-06-01

The proposed quartet theory of human emotions by Koelsch and colleagues [1] identifies four different affect systems to be involved in the processing of particular types of emotions. Moreover, the theory integrates both basic emotions and more complex emotion concepts, which include also aesthetic emotions such as musical emotions. The authors identify a particular brain system for each kind of emotion type, also by contrasting them to brain structures that are generally involved in emotion processing irrespective of the type of emotion. A brain system that has been less regarded in emotion theories, but which represents one of the four systems of the quartet to induce attachment related emotions, is the hippocampus.

Biological and Clinical Aspects of Lanthanide Coordination Compounds

PubMed Central

Misra, Sudhindra N.; M., Indira Devi; Shukla, Ram S.

2004-01-01

The coordinating chemistry of lanthanides, relevant to the biological, biochemical and medical aspects, makes a significant contribution to understanding the basis of application of lanthanides, particularly in biological and medical systems. The importance of the applications of lanthanides, as an excellent diagnostic and prognostic probe in clinical diagnostics, and an anticancer material, is remarkably increasing. Lanthanide complexes based X-ray contrast imaging and lanthanide chelates based contrast enhancing agents for magnetic resonance imaging (MRI) are being excessively used in radiological analysis in our body systems. The most important property of the chelating agents, in lanthanide chelate complex, is its ability to alter the behaviour of lanthanide ion with which it binds in biological systems, and the chelation markedly modifies the biodistribution and excretion profile of the lanthanide ions. The chelating agents, especially aminopoly carboxylic acids, being hydrophilic, increase the proportion of their complex excreted from complexed lanthanide ion form biological systems. Lanthanide polyamino carboxylate-chelate complexes are used as contrast enhancing agents for Magnetic Resonance Imaging. Conjugation of antibodies and other tissue specific molecules to lanthanide chelates has led to a new type of specific MRI contrast agents and their conjugated MRI contrast agents with improved relaxivity, functioning in the body similar to drugs. Many specific features of contrast agent assisted MRI make it particularly effective for musculoskeletal and cerebrospinal imaging. Lanthanide-chelate contrast agents are effectively used in clinical diagnostic investigations involving cerebrospinal diseases and in evaluation of central nervous system. Chelated lanthanide complexes shift reagent aided 23Na NMR spectroscopic analysis is used in cellular, tissue and whole organ systems. PMID:18365075

You Can't Get There From Here! Problems and Potential Solutions in Developing New Classes of Complex Systems

NASA Technical Reports Server (NTRS)

Hinchey, Michael G.; Rash, James L.; Truszkowski, Walter F.; Rouff, Christopher A.; Sterritt, Roy

2005-01-01

The explosion of capabilities and new products within the sphere of Information Technology (IT) has fostered widespread, overly optimistic opinions regarding the industry, based on common but unjustified assumptions of quality and correctness of software. These assumptions are encouraged by software producers and vendors, who at this late date have not succeeded in finding a way to overcome the lack of an automated, mathematically sound way to develop correct systems from requirements. NASA faces this dilemma as it envisages advanced mission concepts that involve large swarms of small spacecraft that will engage cooperatively to acheve science goals. Such missions entail levels of complexity that beg for new methods for system development far beyond today's methods, which are inadequate for ensuring correct behavior of large numbers of interacting intelligent mission elements. New system development techniques recently devised through NASA-led research will offer some innovative approaches to achieving correctness in complex system development, including autonomous swarm missions that exhibit emergent behavior, as well as general software products created by the computing industry.

Discovery Proteomics Identifies a Molecular Link between the Coatomer Protein Complex I and Androgen Receptor-dependent Transcription*

PubMed Central

Hsiao, Jordy J.; Smits, Melinda M.; Ng, Brandon H.; Lee, Jinhee; Wright, Michael E.

2016-01-01

Aberrant androgen receptor (AR)-dependent transcription is a hallmark of human prostate cancers. At the molecular level, ligand-mediated AR activation is coordinated through spatial and temporal protein-protein interactions involving AR-interacting proteins, which we designate the “AR-interactome.” Despite many years of research, the ligand-sensitive protein complexes involved in ligand-mediated AR activation in prostate tumor cells have not been clearly defined. Here, we describe the development, characterization, and utilization of a novel human LNCaP prostate tumor cell line, N-AR, which stably expresses wild-type AR tagged at its N terminus with the streptavidin-binding peptide epitope (streptavidin-binding peptide-tagged wild-type androgen receptor; SBP-AR). A bioanalytical workflow involving streptavidin chromatography and label-free quantitative mass spectrometry was used to identify SBP-AR and associated ligand-sensitive cytosolic proteins/protein complexes linked to AR activation in prostate tumor cells. Functional studies verified that ligand-sensitive proteins identified in the proteomic screen encoded modulators of AR-mediated transcription, suggesting that these novel proteins were putative SBP-AR-interacting proteins in N-AR cells. This was supported by biochemical associations between recombinant SBP-AR and the ligand-sensitive coatomer protein complex I (COPI) retrograde trafficking complex in vitro. Extensive biochemical and molecular experiments showed that the COPI retrograde complex regulates ligand-mediated AR transcriptional activation, which correlated with the mobilization of the Golgi-localized ARA160 coactivator to the nuclear compartment of prostate tumor cells. Collectively, this study provides a bioanalytical strategy to validate the AR-interactome and define novel AR-interacting proteins involved in ligand-mediated AR activation in prostate tumor cells. Moreover, we describe a cellular system to study how compartment-specific AR-interacting proteins influence AR activation and contribute to aberrant AR-dependent transcription that underlies the majority of human prostate cancers. PMID:27365400

Role of Microenvironment in Glioma Invasion: What We Learned from In Vitro Models

PubMed Central

Manini, Ivana; Caponnetto, Federica; Bartolini, Anna; Ius, Tamara; Mariuzzi, Laura; Di Loreto, Carla; Cesselli, Daniela

2018-01-01

The invasion properties of glioblastoma hamper a radical surgery and are responsible for its recurrence. Understanding the invasion mechanisms is thus critical to devise new therapeutic strategies. Therefore, the creation of in vitro models that enable these mechanisms to be studied represents a crucial step. Since in vitro models represent an over-simplification of the in vivo system, in these years it has been attempted to increase the level of complexity of in vitro assays to create models that could better mimic the behaviour of the cells in vivo. These levels of complexity involved: 1. The dimension of the system, moving from two-dimensional to three-dimensional models; 2. The use of microfluidic systems; 3. The use of mixed cultures of tumour cells and cells of the tumour micro-environment in order to mimic the complex cross-talk between tumour cells and their micro-environment; 4. And the source of cells used in an attempt to move from commercial lines to patient-based models. In this review, we will summarize the evidence obtained exploring these different levels of complexity and highlighting advantages and limitations of each system used. PMID:29300332

Special Educators as Intervention Specialists: Dynamic Systems and the Complexity of Intensifying Intervention for Students With Emotional and Behavioral Disorders

ERIC Educational Resources Information Center

Farmer, Thomas W.; Sutherland, Kevin S.; Talbott, Elizabeth; Brooks, Debbie S.; Norwalk, Kate; Huneke, Michelle

2016-01-01

We present a dynamic systems perspective for the intensification of interventions for students with emotional and behavioral disorders (EBD). With this framework, we suggest behavior involves the contributions of multiple factors and reflects the interplay between the characteristics of the student and the ecologies in which he or she is embedded.…

Simulation of Downlink Synchronization for a Frequency-Hopped Satellite Communication System

DTIC Science & Technology

1992-04-01

naflonie SIMULATION OF DOWNLINK SYNCHRONIZATION FOR A FREQUENCY-HOPPED SATELLITE COMMUNICATION SYSTEM (U) by Lyle Waper_Communicadion and Xa elo Elkaoftron...is offset by an increase in complexity while establishing the communication link, termed synchronization . This document describes a downlink... synchronization process that involves the transmission of synchronization hops by the satellite and a two-step ground terminal synchonization procedure. In

Advanced Alarm Systems: Revision of Guidance and Its Technical Basis

DTIC Science & Technology

2000-11-01

was required to generalize from the unique aspects of individual experiments and studies to actual applications in the workplace . This is because...types of equipment used). For example , laboratory experiments often do not involve tasks of the complexity of NPP operations, and most experiments do...Cognitive Compatibility, Situation Awareness, Task Compatibility, and Timeliness. Figure 3.3 Example of an alarm system design review guideline Each

Theorems and application of local activity of CNN with five state variables and one port.

PubMed

Xiong, Gang; Dong, Xisong; Xie, Li; Yang, Thomas

2012-01-01

Coupled nonlinear dynamical systems have been widely studied recently. However, the dynamical properties of these systems are difficult to deal with. The local activity of cellular neural network (CNN) has provided a powerful tool for studying the emergence of complex patterns in a homogeneous lattice, which is composed of coupled cells. In this paper, the analytical criteria for the local activity in reaction-diffusion CNN with five state variables and one port are presented, which consists of four theorems, including a serial of inequalities involving CNN parameters. These theorems can be used for calculating the bifurcation diagram to determine or analyze the emergence of complex dynamic patterns, such as chaos. As a case study, a reaction-diffusion CNN of hepatitis B Virus (HBV) mutation-selection model is analyzed and simulated, the bifurcation diagram is calculated. Using the diagram, numerical simulations of this CNN model provide reasonable explanations of complex mutant phenomena during therapy. Therefore, it is demonstrated that the local activity of CNN provides a practical tool for the complex dynamics study of some coupled nonlinear systems.

Sensemaking in a Value Based Context for Large Scale Complex Engineered Systems

NASA Astrophysics Data System (ADS)

Sikkandar Basha, Nazareen

The design and the development of Large-Scale Complex Engineered Systems (LSCES) requires the involvement of multiple teams and numerous levels of the organization and interactions with large numbers of people and interdisciplinary departments. Traditionally, requirements-driven Systems Engineering (SE) is used in the design and development of these LSCES. The requirements are used to capture the preferences of the stakeholder for the LSCES. Due to the complexity of the system, multiple levels of interactions are required to elicit the requirements of the system within the organization. Since LSCES involves people and interactions between the teams and interdisciplinary departments, it should be socio-technical in nature. The elicitation of the requirements of most large-scale system projects are subjected to creep in time and cost due to the uncertainty and ambiguity of requirements during the design and development. In an organization structure, the cost and time overrun can occur at any level and iterate back and forth thus increasing the cost and time. To avoid such creep past researches have shown that rigorous approaches such as value based designing can be used to control it. But before the rigorous approaches can be used, the decision maker should have a proper understanding of requirements creep and the state of the system when the creep occurs. Sensemaking is used to understand the state of system when the creep occurs and provide a guidance to decision maker. This research proposes the use of the Cynefin framework, sensemaking framework which can be used in the design and development of LSCES. It can aide in understanding the system and decision making to minimize the value gap due to requirements creep by eliminating ambiguity which occurs during design and development. A sample hierarchical organization is used to demonstrate the state of the system at the occurrence of requirements creep in terms of cost and time using the Cynefin framework. These trials are continued for different requirements and at different sub-system level. The results obtained show that the Cynefin framework can be used to improve the value of the system and can be used for predictive analysis. The decision makers can use these findings and use rigorous approaches and improve the design of Large Scale Complex Engineered Systems.

Case management of persons with acquired immunodeficiency syndrome in San Francisco

PubMed Central

Benjamin, A. E.; Lee, Philip R.; Solkowitz, Sharon N.

1988-01-01

The acquired immunodeficiency syndrome (AIDS) epidemic represents a growing challenge for the health care system and for case management models applied to persons with AIDS. The experience of San Francisco highlights some of the issues involved in developing a case management system appropriate to the needs of persons with AIDS, as well as providers, and payers. Dramatic growth in the size and complexity of the AIDS caseload and the involvement of public, health maintenance organization, and community providers has required the increasing formalization and centralization of case management roles. Persistent questions about the definition and goals of case management complicate development of these services. PMID:10312974

Measuring the complexity of design in real-time imaging software

NASA Astrophysics Data System (ADS)

Sangwan, Raghvinder S.; Vercellone-Smith, Pamela; Laplante, Phillip A.

2007-02-01

Due to the intricacies in the algorithms involved, the design of imaging software is considered to be more complex than non-image processing software (Sangwan et al, 2005). A recent investigation (Larsson and Laplante, 2006) examined the complexity of several image processing and non-image processing software packages along a wide variety of metrics, including those postulated by McCabe (1976), Chidamber and Kemerer (1994), and Martin (2003). This work found that it was not always possible to quantitatively compare the complexity between imaging applications and nonimage processing systems. Newer research and an accompanying tool (Structure 101, 2006), however, provides a greatly simplified approach to measuring software complexity. Therefore it may be possible to definitively quantify the complexity differences between imaging and non-imaging software, between imaging and real-time imaging software, and between software programs of the same application type. In this paper, we review prior results and describe the methodology for measuring complexity in imaging systems. We then apply a new complexity measurement methodology to several sets of imaging and non-imaging code in order to compare the complexity differences between the two types of applications. The benefit of such quantification is far reaching, for example, leading to more easily measured performance improvement and quality in real-time imaging code.

Brainlab: A Python Toolkit to Aid in the Design, Simulation, and Analysis of Spiking Neural Networks with the NeoCortical Simulator.

PubMed

Drewes, Rich; Zou, Quan; Goodman, Philip H

2009-01-01

Neuroscience modeling experiments often involve multiple complex neural network and cell model variants, complex input stimuli and input protocols, followed by complex data analysis. Coordinating all this complexity becomes a central difficulty for the experimenter. The Python programming language, along with its extensive library packages, has emerged as a leading "glue" tool for managing all sorts of complex programmatic tasks. This paper describes a toolkit called Brainlab, written in Python, that leverages Python's strengths for the task of managing the general complexity of neuroscience modeling experiments. Brainlab was also designed to overcome the major difficulties of working with the NCS (NeoCortical Simulator) environment in particular. Brainlab is an integrated model-building, experimentation, and data analysis environment for the powerful parallel spiking neural network simulator system NCS.

Brainlab: A Python Toolkit to Aid in the Design, Simulation, and Analysis of Spiking Neural Networks with the NeoCortical Simulator

PubMed Central

Drewes, Rich; Zou, Quan; Goodman, Philip H.

2008-01-01

Neuroscience modeling experiments often involve multiple complex neural network and cell model variants, complex input stimuli and input protocols, followed by complex data analysis. Coordinating all this complexity becomes a central difficulty for the experimenter. The Python programming language, along with its extensive library packages, has emerged as a leading “glue” tool for managing all sorts of complex programmatic tasks. This paper describes a toolkit called Brainlab, written in Python, that leverages Python's strengths for the task of managing the general complexity of neuroscience modeling experiments. Brainlab was also designed to overcome the major difficulties of working with the NCS (NeoCortical Simulator) environment in particular. Brainlab is an integrated model-building, experimentation, and data analysis environment for the powerful parallel spiking neural network simulator system NCS. PMID:19506707

Reasoning and planning in dynamic domains: An experiment with a mobile robot

NASA Technical Reports Server (NTRS)

Georgeff, M. P.; Lansky, A. L.; Schoppers, M. J.

1987-01-01

Progress made toward having an autonomous mobile robot reason and plan complex tasks in real-world environments is described. To cope with the dynamic and uncertain nature of the world, researchers use a highly reactive system to which is attributed attitudes of belief, desire, and intention. Because these attitudes are explicitly represented, they can be manipulated and reasoned about, resulting in complex goal-directed and reflective behaviors. Unlike most planning systems, the plans or intentions formed by the system need only be partly elaborated before it decides to act. This allows the system to avoid overly strong expectations about the environment, overly constrained plans of action, and other forms of over-commitment common to previous planners. In addition, the system is continuously reactive and has the ability to change its goals and intentions as situations warrant. Thus, while the system architecture allows for reasoning about means and ends in much the same way as traditional planners, it also posseses the reactivity required for survival in complex real-world domains. The system was tested using SRI's autonomous robot (Flakey) in a scenario involving navigation and the performance of an emergency task in a space station scenario.

Metrics required for Power System Resilient Operations and Protection

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

Eshghi, K.; Johnson, B. K.; Rieger, C. G.

Today’s complex grid involves many interdependent systems. Various layers of hierarchical control and communication systems are coordinated, both spatially and temporally to achieve gird reliability. As new communication network based control system technologies are being deployed, the interconnected nature of these systems is becoming more complex. Deployment of smart grid concepts promises effective integration of renewable resources, especially if combined with energy storage. However, without a philosophical focus on resilience, a smart grid will potentially lead to higher magnitude and/or duration of disruptive events. The effectiveness of a resilient infrastructure depends upon its ability to anticipate, absorb, adapt to, and/ormore » rapidly recover from a potentially catastrophic event. Future system operations can be enhanced with a resilient philosophy through architecting the complexity with state awareness metrics that recognize changing system conditions and provide for an agile and adaptive response. The starting point for metrics lies in first understanding the attributes of performance that will be qualified. In this paper, we will overview those attributes and describe how they will be characterized by designing a distributed agent that can be applied to the power grid.« less

Motivating Tomorrow's Biologists

ERIC Educational Resources Information Center

Musante, Susan

2012-01-01

The story of biology is far more complex and fascinating than straightforward facts or neatly labeled diagrams of structures and systems. Although exams can motivate students, the key to using these extrinsic motivators to increase student understanding lies in the way the assessments are designed and what they measure. Those involved in…

Systems Biology of Skeletal Muscle: Fiber Type as an Organizing Principle

PubMed Central

Greising, Sarah M; Gransee, Heather M; Mantilla, Carlos B; Sieck, Gary C

2012-01-01

Skeletal muscle force generation and contraction are fundamental to countless aspects of human life. The complexity of skeletal muscle physiology is simplified by fiber type classification where differences are observed from neuromuscular transmission to release of intracellular Ca2+ from the sarcoplasmic reticulum and the resulting recruitment and cycling of cross-bridges. This review uses fiber type classification as an organizing and simplifying principle to explore the complex interactions between the major proteins involved in muscle force generation and contraction. PMID:22811254

The evaluative imaging of mental models - Visual representations of complexity

NASA Technical Reports Server (NTRS)

Dede, Christopher

1989-01-01

The paper deals with some design issues involved in building a system that could visually represent the semantic structures of training materials and their underlying mental models. In particular, hypermedia-based semantic networks that instantiate classification problem solving strategies are thought to be a useful formalism for such representations; the complexity of these web structures can be best managed through visual depictions. It is also noted that a useful approach to implement in these hypermedia models would be some metrics of conceptual distance.

[Occupational and non-occupational factors influencing health state of small and medium business workers].

PubMed

Fasikov, R M; Khuzhakhmetova, I B; Stepanov, E G

2010-01-01

Complex study of work conditions and health parameters of workers engaged into small and medium business proved that preserved and better health of these workers, prevention of occupational and occupationally mediated diseases necessitate federal and regional complex system of measures including legal basis, database on work conditions and their influence on small and medium business workers' health, occupational medicine training for employers and employees, more active involvement of medical institutioins into screening for occupational diseases.

Statistical Analysis of Complexity Generators for Cost Estimation

NASA Technical Reports Server (NTRS)

Rowell, Ginger Holmes

1999-01-01

Predicting the cost of cutting edge new technologies involved with spacecraft hardware can be quite complicated. A new feature of the NASA Air Force Cost Model (NAFCOM), called the Complexity Generator, is being developed to model the complexity factors that drive the cost of space hardware. This parametric approach is also designed to account for the differences in cost, based on factors that are unique to each system and subsystem. The cost driver categories included in this model are weight, inheritance from previous missions, technical complexity, and management factors. This paper explains the Complexity Generator framework, the statistical methods used to select the best model within this framework, and the procedures used to find the region of predictability and the prediction intervals for the cost of a mission.

Syllabus for Weizmann Course: Earth System Science 101

NASA Technical Reports Server (NTRS)

Wiscombe, Warren J.

2011-01-01

This course aims for an understanding of Earth System Science and the interconnection of its various "spheres" (atmosphere, hydrosphere, etc.) by adopting the view that "the microcosm mirrors the macrocosm". We shall study a small set of microcosims, each residing primarily in one sphere, but substantially involving at least one other sphere, in order to illustrate the kinds of coupling that can occur and gain a greater appreciation of the complexity of even the smallest Earth System Science phenomenon.

Mission planning for autonomous systems

NASA Technical Reports Server (NTRS)

Pearson, G.

1987-01-01

Planning is a necessary task for intelligent, adaptive systems operating independently of human controllers. A mission planning system that performs task planning by decomposing a high-level mission objective into subtasks and synthesizing a plan for those tasks at varying levels of abstraction is discussed. Researchers use a blackboard architecture to partition the search space and direct the focus of attention of the planner. Using advanced planning techniques, they can control plan synthesis for the complex planning tasks involved in mission planning.

Combining high performance simulation, data acquisition, and graphics display computers

NASA Technical Reports Server (NTRS)

Hickman, Robert J.

1989-01-01

Issues involved in the continuing development of an advanced simulation complex are discussed. This approach provides the capability to perform the majority of tests on advanced systems, non-destructively. The controlled test environments can be replicated to examine the response of the systems under test to alternative treatments of the system control design, or test the function and qualification of specific hardware. Field tests verify that the elements simulated in the laboratories are sufficient. The digital computer is hosted by a Digital Equipment Corp. MicroVAX computer with an Aptec Computer Systems Model 24 I/O computer performing the communication function. An Applied Dynamics International AD100 performs the high speed simulation computing and an Evans and Sutherland PS350 performs on-line graphics display. A Scientific Computer Systems SCS40 acts as a high performance FORTRAN program processor to support the complex, by generating numerous large files from programs coded in FORTRAN that are required for the real time processing. Four programming languages are involved in the process, FORTRAN, ADSIM, ADRIO, and STAPLE. FORTRAN is employed on the MicroVAX host to initialize and terminate the simulation runs on the system. The generation of the data files on the SCS40 also is performed with FORTRAN programs. ADSIM and ADIRO are used to program the processing elements of the AD100 and its IOCP processor. STAPLE is used to program the Aptec DIP and DIA processors.

A hierarchical approach to cooperativity in macromolecular and self-assembling binding systems.

PubMed

Garcés, Josep Lluís; Acerenza, Luis; Mizraji, Eduardo; Mas, Francesc

2008-04-01

The study of complex macromolecular binding systems reveals that a high number of states and processes are involved in their mechanism of action, as has become more apparent with the sophistication of the experimental techniques used. The resulting information is often difficult to interpret because of the complexity of the scheme (large size and profuse interactions, including cooperative and self-assembling interactions) and the lack of transparency that this complexity introduces into the interpretation of the indexes traditionally used to describe the binding properties. In particular, cooperative behaviour can be attributed to very different causes, such as direct chemical modification of the binding sites, conformational changes in the whole structure of the macromolecule, aggregation processes between different subunits, etc. In this paper, we propose a novel approach for the analysis of the binding properties of complex macromolecular and self-assembling systems. To quantify the binding behaviour, we use the global association quotient defined as K(c) = [occupied sites]/([free sites] L), L being the free ligand concentration. K(c) can be easily related to other measures of cooperativity (such as the Hill number or the Scatchard plot) and to the free energies involved in the binding processes at each ligand concentration. In a previous work, it was shown that K(c) could be decomposed as an average of equilibrium constants in two ways: intrinsic constants for Adair binding systems and elementary constants for the general case. In this study, we show that these two decompositions are particular cases of a more general expression, where the average is over partial association quotients, associated with subsystems from which the system is composed. We also show that if the system is split into different subsystems according to a binding hierarchy that starts from the lower, microscopic level and ends at the higher, aggregation level, the global association quotient can be decomposed following the hierarchical levels of macromolecular organisation. In this process, the partial association quotients of one level are expressed, in a recursive way, as a function of the partial quotients of the level that is immediately below, until the microscopic level is reached. As a result, the binding properties of very complex macromolecular systems can be analysed in detail, making the mechanistic explanation of their behaviour transparent. In addition, our approach provides a model-independent interpretation of the intrinsic equilibrium constants in terms of the elementary ones.

A Mathematical Framework for the Complex System Approach to Group Dynamics: The Case of Recovery House Social Integration.

PubMed

Light, John M; Jason, Leonard A; Stevens, Edward B; Callahan, Sarah; Stone, Ariel

2016-03-01

The complex system conception of group social dynamics often involves not only changing individual characteristics, but also changing within-group relationships. Recent advances in stochastic dynamic network modeling allow these interdependencies to be modeled from data. This methodology is discussed within a context of other mathematical and statistical approaches that have been or could be applied to study the temporal evolution of relationships and behaviors within small- to medium-sized groups. An example model is presented, based on a pilot study of five Oxford House recovery homes, sober living environments for individuals following release from acute substance abuse treatment. This model demonstrates how dynamic network modeling can be applied to such systems, examines and discusses several options for pooling, and shows how results are interpreted in line with complex system concepts. Results suggest that this approach (a) is a credible modeling framework for studying group dynamics even with limited data, (b) improves upon the most common alternatives, and (c) is especially well-suited to complex system conceptions. Continuing improvements in stochastic models and associated software may finally lead to mainstream use of these techniques for the study of group dynamics, a shift already occurring in related fields of behavioral science.

The role of complexity metrics in a multi-institutional dosimetry audit of VMAT

PubMed Central

Agnew, Christina E; Hussein, Mohammad; Tsang, Yatman; McWilliam, Alan; Hounsell, Alan R; Clark, Catharine H

2016-01-01

Objective: To demonstrate the benefit of complexity metrics such as the modulation complexity score (MCS) and monitor units (MUs) in multi-institutional audits of volumetric-modulated arc therapy (VMAT) delivery. Methods: 39 VMAT treatment plans were analysed using MCS and MU. A virtual phantom planning exercise was planned and independently measured using the PTW Octavius® phantom and seven29® 2D array (PTW-Freiburg GmbH, Freiburg, Germany). MCS and MU were compared with the median gamma index pass rates (2%/2 and 3%/3 mm) and plan quality. The treatment planning systems (TPS) were grouped by VMAT modelling being specifically designed for the linear accelerator manufacturer's own treatment delivery system (Type 1) or independent of vendor for VMAT delivery (Type 2). Differences in plan complexity (MCS and MU) between TPS types were compared. Results: For Varian® linear accelerators (Varian® Medical Systems, Inc., Palo Alto, CA), MCS and MU were significantly correlated with gamma pass rates. Type 2 TPS created poorer quality, more complex plans with significantly higher MUs and MCS than Type 1 TPS. Plan quality was significantly correlated with MU for Type 2 plans. A statistically significant correlation was observed between MU and MCS for all plans (R = −0.84, p < 0.01). Conclusion: MU and MCS have a role in assessing plan complexity in audits along with plan quality metrics. Plan complexity metrics give some indication of plan deliverability but should be analysed with plan quality. Advances in knowledge: Complexity metrics were investigated for a national rotational audit involving 34 institutions and they showed value. The metrics found that more complex plans were created for planning systems which were independent of vendor for VMAT delivery. PMID:26511276

The role of complexity metrics in a multi-institutional dosimetry audit of VMAT.

PubMed

McGarry, Conor K; Agnew, Christina E; Hussein, Mohammad; Tsang, Yatman; McWilliam, Alan; Hounsell, Alan R; Clark, Catharine H

2016-01-01

To demonstrate the benefit of complexity metrics such as the modulation complexity score (MCS) and monitor units (MUs) in multi-institutional audits of volumetric-modulated arc therapy (VMAT) delivery. 39 VMAT treatment plans were analysed using MCS and MU. A virtual phantom planning exercise was planned and independently measured using the PTW Octavius(®) phantom and seven29(®) 2D array (PTW-Freiburg GmbH, Freiburg, Germany). MCS and MU were compared with the median gamma index pass rates (2%/2 and 3%/3 mm) and plan quality. The treatment planning systems (TPS) were grouped by VMAT modelling being specifically designed for the linear accelerator manufacturer's own treatment delivery system (Type 1) or independent of vendor for VMAT delivery (Type 2). Differences in plan complexity (MCS and MU) between TPS types were compared. For Varian(®) linear accelerators (Varian(®) Medical Systems, Inc., Palo Alto, CA), MCS and MU were significantly correlated with gamma pass rates. Type 2 TPS created poorer quality, more complex plans with significantly higher MUs and MCS than Type 1 TPS. Plan quality was significantly correlated with MU for Type 2 plans. A statistically significant correlation was observed between MU and MCS for all plans (R = -0.84, p < 0.01). MU and MCS have a role in assessing plan complexity in audits along with plan quality metrics. Plan complexity metrics give some indication of plan deliverability but should be analysed with plan quality. Complexity metrics were investigated for a national rotational audit involving 34 institutions and they showed value. The metrics found that more complex plans were created for planning systems which were independent of vendor for VMAT delivery.

Modelling and simulation of complex sociotechnical systems: envisioning and analysing work environments

PubMed Central

Hettinger, Lawrence J.; Kirlik, Alex; Goh, Yang Miang; Buckle, Peter

2015-01-01

Accurate comprehension and analysis of complex sociotechnical systems is a daunting task. Empirically examining, or simply envisioning the structure and behaviour of such systems challenges traditional analytic and experimental approaches as well as our everyday cognitive capabilities. Computer-based models and simulations afford potentially useful means of accomplishing sociotechnical system design and analysis objectives. From a design perspective, they can provide a basis for a common mental model among stakeholders, thereby facilitating accurate comprehension of factors impacting system performance and potential effects of system modifications. From a research perspective, models and simulations afford the means to study aspects of sociotechnical system design and operation, including the potential impact of modifications to structural and dynamic system properties, in ways not feasible with traditional experimental approaches. This paper describes issues involved in the design and use of such models and simulations and describes a proposed path forward to their development and implementation. Practitioner Summary: The size and complexity of real-world sociotechnical systems can present significant barriers to their design, comprehension and empirical analysis. This article describes the potential advantages of computer-based models and simulations for understanding factors that impact sociotechnical system design and operation, particularly with respect to process and occupational safety. PMID:25761227

Neurocutaneous Melanosis in Association with Dandy-Walker Complex with Extensive Intracerebral and Spinal Cord Involvement

PubMed Central

Sung, Kyoung-Su

2014-01-01

Neurocutaneous melanosis (NCM) is a rare congenital syndrome consisting of benign or malignant melanotic tumors of the central nervous system with large or numerous cutaneous melanocytic nevi. The Dandy-Walker complex (DWC) is characterized by an enlarged posterior fossa with high insertion of the tentorium, hypoplasia or aplasia of the cerebellar vermis, and cystic dilatation of the fourth ventricle. These each two conditions are rare, but NCM associated with DWC is even more rare. Most patients of NCM with DWC present neurological symptoms early in life such as intracranial hemorrhage, hydrocephalus, and malignant transformation of the melanocytes. We report a 14-year-old male patient who was finally diagnosed as NCM in association with DWC with extensive intracerebral and spinal cord involvement. PMID:25289129

A high performance, ad-hoc, fuzzy query processing system for relational databases

NASA Technical Reports Server (NTRS)

Mansfield, William H., Jr.; Fleischman, Robert M.

1992-01-01

Database queries involving imprecise or fuzzy predicates are currently an evolving area of academic and industrial research. Such queries place severe stress on the indexing and I/O subsystems of conventional database environments since they involve the search of large numbers of records. The Datacycle architecture and research prototype is a database environment that uses filtering technology to perform an efficient, exhaustive search of an entire database. It has recently been modified to include fuzzy predicates in its query processing. The approach obviates the need for complex index structures, provides unlimited query throughput, permits the use of ad-hoc fuzzy membership functions, and provides a deterministic response time largely independent of query complexity and load. This paper describes the Datacycle prototype implementation of fuzzy queries and some recent performance results.

Functional specifications for a radioactive waste decision support system

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

Westrom, G.B.; Kurrasch, E.R.; Carlton, R.E.

1989-09-01

It is generally recognized that decisions relative to the treatment, handling, transportation and disposal of low-level wastes produced in nuclear power plants involve a complex array of many inter-related elements or considerations. Complex decision processes can be aided through the use of computer-based expert systems which are based on the knowledge of experts and the inferencing of that knowledge to provide advice to an end-user. To determine the feasibility of developing and applying an expert system in nuclear plant low level waste operations, a Functional Specification for a Radwaste Decision Support System (RDSS) was developed. All areas of radwaste management,more » from the point of waste generation to the disposition of the waste in the final disposal location were considered for inclusion within the scope of the RDSS. 27 figs., 8 tabs.« less

Advances in Robotic, Human, and Autonomous Systems for Missions of Space Exploration

NASA Technical Reports Server (NTRS)

Gross, Anthony R.; Briggs, Geoffrey A.; Glass, Brian J.; Pedersen, Liam; Kortenkamp, David M.; Wettergreen, David S.; Nourbakhsh, I.; Clancy, Daniel J.; Zornetzer, Steven (Technical Monitor)

2002-01-01

Space exploration missions are evolving toward more complex architectures involving more capable robotic systems, new levels of human and robotic interaction, and increasingly autonomous systems. How this evolving mix of advanced capabilities will be utilized in the design of new missions is a subject of much current interest. Cost and risk constraints also play a key role in the development of new missions, resulting in a complex interplay of a broad range of factors in the mission development and planning of new missions. This paper will discuss how human, robotic, and autonomous systems could be used in advanced space exploration missions. In particular, a recently completed survey of the state of the art and the potential future of robotic systems, as well as new experiments utilizing human and robotic approaches will be described. Finally, there will be a discussion of how best to utilize these various approaches for meeting space exploration goals.

The structure of control and data transfer management system for the GAMMA-400 scientific complex

NASA Astrophysics Data System (ADS)

Arkhangelskiy, A. I.; Bobkov, S. G.; Serdin, O. V.; Gorbunov, M. S.; Topchiev, N. P.

2016-02-01

A description of the control and data transfer management system for scientific instrumentation involved in the GAMMA-400 space project is given. The technical capabilities of all specialized equipment to provide the functioning of the scientific instrumentation and satellite support systems are unified in a single structure. Control of the scientific instruments is maintained using one-time pulse radio commands, as well as program commands in the form of 16-bit code words, which are transmitted via onboard control system and scientific data acquisition system. Up to 100 GByte of data per day can be transferred to the ground segment of the project. The correctness of the proposed and implemented structure, engineering solutions and electronic elemental base selection has been verified by the experimental working-off of the prototype of the GAMMA-400 scientific complex in laboratory conditions.

Cyclodextrin based ternary system of modafinil: Effect of trimethyl chitosan and polyvinylpyrrolidone as complexing agents.

PubMed

Patel, Parth; Agrawal, Y K; Sarvaiya, Jayrajsinh

2016-03-01

Modafinil is an approved drug for the treatment of narcolepsy and have a strong market presence in many countries. The drug is widely consumed for off-label uses and currently listed as a restricted drug. Modafinil has very low water solubility. To enhance the aqueous solubility of modafinil by the formation of a ternary complex with Hydroxypropyl-β-cyclodextrin and two hydrophilic polymers was the main objective of the present study. Pyrrolidone (PVP K30) and a water soluble chitosan derivative, trimethyl chitosan (TMC) were studied by solution state and solid state characterization methods for their discriminatory efficiency in solubility enhancement of modafinil. Phase solubility study depicted the highest complexation efficiency (2.22) of cyclodextrin derivative in the presence of TMC compared to the same in the presence of PVP K30 (0.08) and in the absence of any polymer (0.92). FT-IR analysis of binary and ternary complex expressed comparable contribution of both polymers in formation of inclusion complex. The thermal behaviour of binary and ternary complex, involving individual polymers disclosed the influence of TMC on polymorphism of the drug. DSC study revealed efficiency of TMC to prevent conversion of metastable polymorphic form to stable polymorphic form. Ternary complex, involving TMC enhanced water solubility of the drug 1.5 times more compared to the binary complex of the drug whereas PVP K30 reduced the Solubility. Copyright © 2015 Elsevier B.V. All rights reserved.

Advanced software integration: The case for ITV facilities

NASA Technical Reports Server (NTRS)

Garman, John R.

1990-01-01

The array of technologies and methodologies involved in the development and integration of avionics software has moved almost as rapidly as computer technology itself. Future avionics systems involve major advances and risks in the following areas: (1) Complexity; (2) Connectivity; (3) Security; (4) Duration; and (5) Software engineering. From an architectural standpoint, the systems will be much more distributed, involve session-based user interfaces, and have the layered architectures typified in the layers of abstraction concepts popular in networking. Typified in the NASA Space Station Freedom will be the highly distributed nature of software development itself. Systems composed of independent components developed in parallel must be bound by rigid standards and interfaces, the clean requirements and specifications. Avionics software provides a challenge in that it can not be flight tested until the first time it literally flies. It is the binding of requirements for such an integration environment into the advances and risks of future avionics systems that form the basis of the presented concept and the basic Integration, Test, and Verification concept within the development and integration life cycle of Space Station Mission and Avionics systems.

Spectral investigations on binding of DNA-CTMA complex with tetrameric copper phthalocyanines

NASA Astrophysics Data System (ADS)

Venkat, Narayanan; Haley, Joy E.; Swiger, Rachel; Zhu, Lei; Wei, Xiaoliang; Ouchen, Fahima; Grote, James G.

2013-10-01

The binding of DNA-CTMA (Deoxyribonucleic acid-cetyltrimethylammonium) complex with two tetrameric Copper Phthalocyanine (CuPc) systems, substituted with carboxylic acid (CuPc-COOH) and derivatized further as an imidazolium salt (CuPc-COOR), was investigated in dimethylsulfoxide (DMSO) solutions using UV/Visible Spectroscopy. Absorbance changes at 685 nm (Q band of the CuPc) were monitored as a function of DNA-CTMA added to the dye solution and stock concentrations of DNA-CTMA in DMSO were varied to facilitate observation of the full binding process. Our findings indicated that while binding with DNA-CTMA was more well-defined in the case of CuPc-COOH, the binding profile of the CuPc-COOR showed initial growth followed by decay in its Q-band absorbance which was indicative of a more complex binding mechanism involving the dye and DNA-CTMA. Preliminary findings from photophysical studies involving the CuPc tetramers and DNA-CTMA are also discussed in this paper.

Neuropsychiatry of complex visual hallucinations.

PubMed

Mocellin, Ramon; Walterfang, Mark; Velakoulis, Dennis

2006-09-01

To describe the phenomenology and pathophysiology of complex visual hallucinations (CVH) in various organic states, in particular Charles Bonnet syndrome and peduncular hallucinosis. Three cases of CVH in the setting of pontine infarction, thalamic infarction and temporoparietal epileptiform activity are presented and the available psychiatric, neurological and biological literature on the structures of the central nervous system involved in producing hallucinatory states is reviewed. Complex visual hallucinations can arise from a variety of processes involving the retinogeniculocalcarine tract, or ascending brainstem modulatory structures. The cortical activity responsible for hallucinations results from altered or reduced input into these regions, or a loss of ascending inhibition of their afferent pathways. A significant degree of overlaps exists between the concepts of Charles Bonnet syndrome and peduncular hallucinosis. The fluidity of these eponymous syndromes reduces their validity and meaning, and may result in an inappropriate attribution of the underlying pathology. An understanding of how differing pathologies may produce CVH allows for the appropriate tailoring of treatment, depending on the site and nature of the lesion and content of perceptual disturbance.

Siderophore-drug complexes: potential medicinal applications of the 'Trojan horse' strategy.

PubMed

Górska, Agnieszka; Sloderbach, Anna; Marszałł, Michał Piotr

2014-09-01

The ability of bacteria to develop resistance to antimicrobial agents poses problems in the treatment of numerous bacterial infections. One method to circumvent permeability-mediated drug resistance involves the employment of the 'Trojan horse' strategy. The Trojan horse concept involves the use of bacterial iron uptake systems to enter and kill bacteria. The siderophore-drug complex is recognized by specific siderophore receptors and is then actively transported across the outer membrane. The recently identified benefits of this strategy have led to the synthesis of a series of siderophore-based antibiotics. Several studies have shown that siderophore-drug conjugates make it possible to design antibiotics with improved cell transport and reduce the frequency of resistance mutants. Growing interest in siderophore-drug conjugates for the treatment of human diseases including iron overload, cancer, and malaria has driven the search for new siderophore-drug complexes. This strategy may have special importance for the development of iron oxide nanoparticle-based therapeutics. Copyright © 2014 Elsevier Ltd. All rights reserved.

Using three dimensional silicone ``boots`` to solve complex remedial design problems in curtain walls

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

Chen, Y.J.

1998-12-31

Stick system curtain wall leak problems are frequently caused by water entry at the splice joints of the curtain wall frame and failure of the internal metal joinery seals. Remedial solutions involving occupied buildings inevitably face the multiple constraints of existing construction and business operations not present during the original curtain wall construction. In most cases, even partial disassembly of the curtain wall for internal seal repairs is not feasible. Remedial solutions which must be executed from the exterior of the curtain wall often involve wet-applied or preformed sealant tape bridge joints. However, some of the more complex joints cannotmore » be repaired effectively or economically with the conventional bridge joint. Fortunately, custom fabricated three-dimensional preformed sealant boots are becoming available to address these situations. This paper discusses the design considerations and the selective use of three-dimensional preformed boots in sealing complex joint geometry that would not be effective with the conventional two-dimensional bridge joint.« less

[Consensus conferences in Israel--a collaborative model for national policy making].

PubMed

Tal, Orna; Oberlander, Shira; Siebzehner, Miri I

2014-07-01

The determination of an integrated national policy on controversial issues is a challenge for health systems worldwide. A common method to reach agreements for national policies in different countries throughout the world is group discussion that involves all stakeholders. A structured model of discussion on medical technologies started in the 1970s, mostly in North America, spreading to Europe and in the last decade also crossed borders to India, South America and Israel. Public discussion in the format of a consensus conference is a complex process that includes a thorough literature review for technology assessment, combining academic information using a technique of close consultation with experts, extensive panel discussion and dialogue with representatives of the public. At the end of the process a broad consensus is determined facilitating national-level policy implementation. The multiple factors involved, the issues addressed, the nature of the health system where the intended results will be applied, as well as political and social characteristics, produce variations among different countries. Therefore, this process requires flexibility in adjusting the classic model according to the awakening needs. The advantages of this method include encouraging the appropriate utilization of existing technologies, contemporary assessment by leading experts, aligning between all involved parties, public sharing and more. The initial model of the consensus conference was implemented in an orderly, systematic, structured process which allowed broad discussion, and many factors for thorough preparation. The disadvantages are its complexity, length and cost. In order to cope with the dynamics of the health system in israel, forcing policymakers to make decisions in real time, parts of the model were adjusted to address the issues arising in the system. Hence, a new process was developed--a derivative of the original Israeli model, with an emphasis on professional reviews, group discussion, and involvement of leading factors in the system. The participation of patients and the public in the process requires a thorough examination.

CT and MR imaging findings of lymphangioleiomyomatosis involving the uterus and pelvic cavity.

PubMed

Kim, You Sung; Rha, Sung Eun; Byun, Jae Young; Lee, Ahwon; Park, Jong Sup

2011-01-01

Lymphangioleiomyomatosis (LAM) is a rare idiopathic disease and this is characterized by a proliferation of abnormal smooth muscle cells in the lungs and in the lymphatic system of the thorax and retroperitoneum. The female genital tract is rarely affected by LAM. We report here on the CT and MR imaging findings of extensive LAM involving the uterus and pelvic cavity, and this was seen as multiple cystic uterine and parauterine masses with internal hemorrhage in a young female with tuberous sclerosis complex.

Substituted decision making: elder guardianship.

PubMed

Leatherman, Martha E; Goethe, Katherine E

2009-11-01

The goal of this column is to help experienced clinicians navigate the judicial system when they are confronted with requests for capacity evaluations that involve guardianship (conservatorship). The interface between the growing elderly medical population and increasing requests for substituted decision making is becoming more complex. This column will help practicing psychiatrists understand the medical, legal, and societal factors involved in adult guardianship. Such understanding is necessary in order to effectively perform guardianship evaluations and adequately inform courts, patients, and families about the psychiatric diagnoses central to substituted decision making.

Spherical Coordinate Systems for Streamlining Suited Mobility Analysis

NASA Technical Reports Server (NTRS)

Benson, Elizabeth; Cowley, Matthew; Harvill, Lauren; Rajulu. Sudhakar

2015-01-01

Introduction: When describing human motion, biomechanists generally report joint angles in terms of Euler angle rotation sequences. However, there are known limitations in using this method to describe complex motions such as the shoulder joint during a baseball pitch. Euler angle notation uses a series of three rotations about an axis where each rotation is dependent upon the preceding rotation. As such, the Euler angles need to be regarded as a set to get accurate angle information. Unfortunately, it is often difficult to visualize and understand these complex motion representations. It has been shown that using a spherical coordinate system allows Anthropometry and Biomechanics Facility (ABF) personnel to increase their ability to transmit important human mobility data to engineers, in a format that is readily understandable and directly translatable to their design efforts. Objectives: The goal of this project was to use innovative analysis and visualization techniques to aid in the examination and comprehension of complex motions. Methods: This project consisted of a series of small sub-projects, meant to validate and verify a new method before it was implemented in the ABF's data analysis practices. A mechanical test rig was built and tracked in 3D using an optical motion capture system. Its position and orientation were reported in both Euler and spherical reference systems. In the second phase of the project, the ABF estimated the error inherent in a spherical coordinate system, and evaluated how this error would vary within the reference frame. This stage also involved expanding a kinematic model of the shoulder to include the rest of the joints of the body. The third stage of the project involved creating visualization methods to assist in interpreting motion in a spherical frame. These visualization methods will be incorporated in a tool to evaluate a database of suited mobility data, which is currently in development. Results: Initial results demonstrated that a spherical coordinate system is helpful in describing and visualizing the motion of a space suit. The system is particularly useful in describing the motion of the shoulder, where multiple degrees of freedom can lead to very complex motion paths.

Carbohydrates in Supramolecular Chemistry.

PubMed

Delbianco, Martina; Bharate, Priya; Varela-Aramburu, Silvia; Seeberger, Peter H

2016-02-24

Carbohydrates are involved in a variety of biological processes. The ability of sugars to form a large number of hydrogen bonds has made them important components for supramolecular chemistry. We discuss recent advances in the use of carbohydrates in supramolecular chemistry and reveal that carbohydrates are useful building blocks for the stabilization of complex architectures. Systems are presented according to the scaffold that supports the glyco-conjugate: organic macrocycles, dendrimers, nanomaterials, and polymers are considered. Glyco-conjugates can form host-guest complexes, and can self-assemble by using carbohydrate-carbohydrate interactions and other weak interactions such as π-π interactions. Finally, complex supramolecular architectures based on carbohydrate-protein interactions are discussed.

Design consideration in constructing high performance embedded Knowledge-Based Systems (KBS)

NASA Technical Reports Server (NTRS)

Dalton, Shelly D.; Daley, Philip C.

1988-01-01

As the hardware trends for artificial intelligence (AI) involve more and more complexity, the process of optimizing the computer system design for a particular problem will also increase in complexity. Space applications of knowledge based systems (KBS) will often require an ability to perform both numerically intensive vector computations and real time symbolic computations. Although parallel machines can theoretically achieve the speeds necessary for most of these problems, if the application itself is not highly parallel, the machine's power cannot be utilized. A scheme is presented which will provide the computer systems engineer with a tool for analyzing machines with various configurations of array, symbolic, scaler, and multiprocessors. High speed networks and interconnections make customized, distributed, intelligent systems feasible for the application of AI in space. The method presented can be used to optimize such AI system configurations and to make comparisons between existing computer systems. It is an open question whether or not, for a given mission requirement, a suitable computer system design can be constructed for any amount of money.

Immunology for physicists

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

Perelson, A.S.; Weisbuch, G.

1997-10-01

The immune system is a complex system of cells and molecules that can provide us with a basic defense against pathogenic organisms. Like the nervous system, the immune system performs pattern recognition tasks, learns, and retains a memory of the antigens that it has fought. The immune system contains more than 10{sup 7} different clones of cells that communicate via cell-cell contact and the secretion of molecules. Performing complex tasks such as learning and memory involves cooperation among large numbers of components of the immune system and hence there is interest in using methods and concepts from statistical physics. Furthermore,more » the immune response develops in time and the description of its time evolution is an interesting problem in dynamical systems. In this paper, the authors provide a brief introduction to the biology of the immune system and discuss a number of immunological problems in which the use of physical concepts and mathematical methods has increased our understanding. {copyright} {ital 1997} {ital The American Physical Society}« less

Rethinking Communication in Innovation Processes: Creating Space for Change in Complex Systems

ERIC Educational Resources Information Center

Leeuwis, Cees; Aarts, Noelle

2011-01-01

This paper systematically rethinks the role of communication in innovation processes, starting from largely separate theoretical developments in communication science and innovation studies. Literature review forms the basis of the arguments presented. The paper concludes that innovation is a collective process that involves the contextual…

Mortality and Population Dynamics of Bemisia tabaci within a Multi-Crop System

USDA-ARS?s Scientific Manuscript database

The population dynamics of mobile polyphagous pests is governed by a complex set of interacting factors that involve multiple host-plants, seasonality, movement and demography. Bemisia tabaci is a multivoltine insect with no diapause that maintains population continuity by moving from one host to a...

Quasi 3D modeling of water flow in vadose zone and groundwater

USDA-ARS?s Scientific Manuscript database

The complexity of subsurface flow systems calls for a variety of concepts leading to the multiplicity of simplified flow models. One habitual simplification is based on the assumption that lateral flow and transport in unsaturated zone are not significant unless the capillary fringe is involved. In ...

Learning to See the (W)holes

ERIC Educational Resources Information Center

Burns, Barbara A.; Jordan, Thomas M.

2006-01-01

Business managers are faced with complex decisions involving a wide range of issues--technical, social, environmental, and financial--and their interaction. Our education system focuses heavily on presenting structured problems and teaching students to apply a set of tools or methods to solve these problems. Yet the most difficult thing to teach…

The Importance of Action Research in Teacher Education Programs

ERIC Educational Resources Information Center

Hine, Gregory S. C.

2013-01-01

Following entry into the workforce, there are limited opportunities for new graduate teachers to engage in critically reflective activities about their educative practice. In an increasingly complex and challenging profession, the need for teachers, administrators and school systems to become involved in professional development activities is ever…

HIV Education in the Formal Curriculum

ERIC Educational Resources Information Center

Nsubuga, Yusuf K.; Bonnet, Sandrine

2009-01-01

The AIDS epidemic presents a complex of issues that require global answers, involving entire societies. The only sustainable solution is to include all sectors of society in a multidisciplinary collaboration, within which the formal education system plays a key role in delivering a comprehensive response to the disease at the national level.…

Architecture for Implementation of a Lifelong Online Learning Environment (LOLE)

ERIC Educational Resources Information Center

Caron, Philippe; Beaudoin, Gregg; Leblanc, Frederic; Grant, Andrew

2007-01-01

This article describes an architecture for the implementation of a lifelong online learning environment (LOLE). The stakeholder independent architecture enables the development of a LOLE system to fulfill the complex requirements of the different actors involved in lifelong education. A particular emphasis is placed on the continuation of a…

Tips for Ensuring Successful Software Implementation

ERIC Educational Resources Information Center

Weathers, Robert

2013-01-01

Implementing an enterprise-level, mission-critical software system is an infrastructure project akin to other sizable projects, such as building a school. It's costly and complex, takes a year or more to complete, requires the collaboration of many different parties, involves uncertainties, results in a long-lived asset requiring ongoing…

Districts Created to Steer "Turnarounds"

ERIC Educational Resources Information Center

Samuels, Christina A.

2011-01-01

If the job of a traditional superintendent is hard, imagine the complexities involved in building a school system from scratch--especially one composed of schools with some of the most intractable educational challenges. That's the task facing education leaders in Michigan and Tennessee, which are building special districts to take over…

The Self-Systems: Facilitating Personal Well-Being Experiences at School

ERIC Educational Resources Information Center

Phan, Huy P.

2017-01-01

The focus of inquiry pertaining to quality learning and student well-being experiences at school has involved numerous studies, utilizing complex quantitative methodological approaches. In a similar vein, for consideration of research advancement, there has been extensive progress made regarding motivational tenets of effective learning and…

COMPUTER SIMULATIONS OF LUNG AIRWAY STRUCTURES USING DATA-DRIVEN SURFACE MODELING TECHNIQUES

EPA Science Inventory

ABSTRACT

Knowledge of human lung morphology is a subject critical to many areas of medicine. The visualization of lung structures naturally lends itself to computer graphics modeling due to the large number of airways involved and the complexities of the branching systems...

An Isotopic Dilution Experiment Using Liquid Scintillation: A Simple Two-System, Two-Phase Analysis.

ERIC Educational Resources Information Center

Moehs, Peter J.; Levine, Samuel

1982-01-01

A simple isotonic, dilution analysis whose principles apply to methods of more complex radioanalyses is described. Suitable for clinical and instrumental analysis chemistry students, experimental manipulations are kept to a minimum involving only aqueous extraction before counting. Background information, procedures, and results are discussed.…

48 CFR 315.201 - Exchanges with industry before receipt of proposals.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Exchanges with industry... Receipt of Proposals and Information 315.201 Exchanges with industry before receipt of proposals. (e)(1... complex projects involving R & D, IT, construction, and other highly technical requirements. An RFI may...

Adaptation of neuronal signaling and cell stress response pathways in a multigenic response of Drosophila melanogaster to DDT selection

USDA-ARS?s Scientific Manuscript database

The adaptation of insect populations to insecticidal control is a continual threat human health and sustainable agriculture practices, but many complex genomic mechanisms involved remain poorly understood. A systems approach was applied to investigate the interconnections between structural and func...

Farms and Learning Partnerships in Farming Systems Projects: A Response to the Challenges of Complexity in Agricultural Innovation

ERIC Educational Resources Information Center

Crawford, Anne; Nettle, Ruth; Paine, Mark; Kabore, Carolyn

2007-01-01

Managing the competing interests of productivity growth, environmental concerns, landscape change and societal expectations presents challenges for agricultural industries. Innovation projects supporting knowledge development to address these challenges often involve partnerships with commercial farms, a methodology which promises much but has…

School Community Connectedness and Family Participation at School

ERIC Educational Resources Information Center

Dove, Meghan K.; Zorotovich, Jennifer; Gregg, Katy

2018-01-01

Family involvement in a child's education is a complex system that extends beyond the presence of partnerships between families, schools, and the community (Epstein, 2011). By measuring families' feelings of connectedness and membership to the school community, this study explores families' motivations for participating in their child's learning…

Defying Definition: Rethinking Education Aid Relationships in Solomon Islands

ERIC Educational Resources Information Center

Spratt, Rebecca

2016-01-01

The discourse of aid--its language, structures and practice--powerfully ascribes roles and attributes to those involved in aid relationships such as developed/developing, partner, recipient/donor etcetera. This discourse is driven by a complex system of diverse and often competing ideas, values, actors and relationships, within which individuals…

Leadership Development among a Cohort of Undergraduate Interdisciplinary Students in the Health Professions

ERIC Educational Resources Information Center

McKinney, Nicole S.; Waite, Roberta

2016-01-01

Leadership content and pedagogical strategies are fundamental to health professionals' education. All health professionals must be able to lead effectively and thrive in today's complex health systems. Students must be involved in meaningful didactic and experiential leadership development early in their academic progression, and educators are…

'We didn't know anything, it was a mess!' Emergent structures and the effectiveness of a rescue operation multi-team system.

PubMed

Fleştea, Alina Maria; Fodor, Oana Cătălina; Curşeu, Petru Lucian; Miclea, Mircea

2017-01-01

Multi-team systems (MTS) are used to tackle unpredictable events and to respond effectively to fast-changing environmental contingencies. Their effectiveness is influenced by within as well as between team processes (i.e. communication, coordination) and emergent phenomena (i.e. situational awareness). The present case study explores the way in which the emergent structures and the involvement of bystanders intertwine with the dynamics of processes and emergent states both within and between the component teams. Our findings show that inefficient transition process and the ambiguous leadership generated poor coordination and hindered the development of emergent phenomena within the whole system. Emergent structures and bystanders substituted leadership functions and provided a pool of critical resources for the MTS. Their involvement fostered the emergence of situational awareness and facilitated contingency planning processes. However, bystander involvement impaired the emergence of cross-understandings and interfered with coordination processes between the component teams. Practitioner Summary: Based on a real emergency situation, the present research provides important theoretical and practical insights about the role of bystander involvement in the dynamics of multi-team systems composed to tackle complex tasks and respond to fast changing and unpredictable environmental contingencies.

Proposal for an integrated evaluation model for the study of whole systems health care in cancer.

PubMed

Jonas, Wayne B; Beckner, William; Coulter, Ian

2006-12-01

For more than 200 years, biomedicine has approached the treatment of disease by studying disease processes (patho-genesis), inferring causal connections and developing specific approaches for therapeutically interfering with those processes. This pathogenic approach has been highly successful in acute and traumatic disease but less successful in chronic disease, primarily because of the complex, multi-factorial nature of most chronic disease, which does not allow for simple causal inference or for simple therapeutic interventions. This article suggests that chronic disease is best approached by enhancing healing processes (salutogenesis) as a whole system. Because of the nature of complex systems in chronic disease, an evaluation model based on integrative medicine is felt to be more appropriate than a disease model. The authors propose and describe an integrated model for the evaluation of healing (IMEH) that collects multilevel "thick case" observational data in assessing complex practices for chronic disease. If successful, this approach could become a blueprint for studying healing capacity in whole medical systems, including complementary medicine, traditional medicine, and conventional primary care. In addition, streamlining data collection and applying rapid informatics management might allow for such data to be used in guiding clinical practice. The IMEH involves collection, integration, and potentially feedback of relevant variables in the following areas: (1) sociocultural, (2) psychological and behavioral, (3) clinical (diagnosis based), and (4) biological. Evaluation and integration of these components would involve specialized research teams that feed their data into a single data management and information analysis center. These data can then be subjected to descriptive and pathway analysis providing "bench and bedside" information.

Development of an integrated control and measurement system

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

Manges, W.W.

1984-03-01

This thesis presents a tutorial on the issues involved in the development of a minicomputer-based, distributed intelligence data acquisition and process control system to support complex experimental facilities. The particular system discussed in this thesis is under development for the Atomic Vapor Laser Isotope Separation (AVLIS) Program at the Oak Ridge Gaseous Diffusion Plant (ORGDP). In the AVLIS program, we were careful to integrate the computer sections of the implementation into the instrumentation system rather than adding them as an appendage. We then addressed the reliability and availability of the system as a separate concern. Thus, our concept of anmore » integrated control and measurement (ICAM) system forms the basis for this thesis. This thesis details the logic and philosophy that went into the development of this system and explains why the commercially available turn-key systems generally are not suitable. Also, the issues involved in the specification of the components for such an integrated system are emphasized.« less

Ethics: An Indispensable Dimension in the University Rankings.

PubMed

Khaki Sedigh, Ali

2017-02-01

University ranking systems attempt to provide an ordinal gauge to make an expert evaluation of the university's performance for a general audience. University rankings have always had their pros and cons in the higher education community. Some seriously question the usefulness, accuracy, and lack of consensus in ranking systems and therefore multidimensional ranking systems have been proposed to overcome some shortcomings of the earlier systems. Although the present ranking results may rather be rough, they are the only available sources that illustrate the complex university performance in a tangible format. Their relative accuracy has turned the ranking systems into an essential feature of the academic lifecycle within the foreseeable future. The main concern however, is that the present ranking systems totally neglect the ethical issues involved in university performances. Ethics should be a new dimension added into the university ranking systems, as it is an undisputable right of the public and all the parties involved in higher education to have an ethical evaluation of the university's achievements. In this paper, to initiate ethical assessment and rankings, the main factors involved in the university performances are reviewed from an ethical perspective. Finally, a basic benchmarking model for university ethical performance is presented.

DNA binding of supramolecular mixed-metal complexes

NASA Astrophysics Data System (ADS)

Swavey, Shawn; Williams, Rodd L.; Fang, Zhenglai; Milkevitch, Matthew; Brewer, Karen J.

2001-10-01

The high binding affinity of cisplatin toward DNA has led to its popularity as an anticancer agent. Due to cumulative drug resistance and toxic side effects, researchers are exploring related metallodrugs. Our approach involves the use of supramolecular complexes. These mixed-metal complexes incorporate a reactive platinum moiety bridged by a polyazine ligand to a light absorbing metal-based chromophore. The presence of the light absorber allows excitation of these systems, opening up the possibility of photoactivation. The use of a supramolecular design allows components of the assembly to be varied to enhance device function and light absorbing properties. Aspects of our molecular design process and results on the DNA binding properties for a number of these mixed-metal complexes will be discussed.

An Integrated Crustal Dynamics Simulator

NASA Astrophysics Data System (ADS)

Xing, H. L.; Mora, P.

2007-12-01

Numerical modelling offers an outstanding opportunity to gain an understanding of the crustal dynamics and complex crustal system behaviour. This presentation provides our long-term and ongoing effort on finite element based computational model and software development to simulate the interacting fault system for earthquake forecasting. A R-minimum strategy based finite-element computational model and software tool, PANDAS, for modelling 3-dimensional nonlinear frictional contact behaviour between multiple deformable bodies with the arbitrarily-shaped contact element strategy has been developed by the authors, which builds up a virtual laboratory to simulate interacting fault systems including crustal boundary conditions and various nonlinearities (e.g. from frictional contact, materials, geometry and thermal coupling). It has been successfully applied to large scale computing of the complex nonlinear phenomena in the non-continuum media involving the nonlinear frictional instability, multiple material properties and complex geometries on supercomputers, such as the South Australia (SA) interacting fault system, South California fault model and Sumatra subduction model. It has been also extended and to simulate the hot fractured rock (HFR) geothermal reservoir system in collaboration of Geodynamics Ltd which is constructing the first geothermal reservoir system in Australia and to model the tsunami generation induced by earthquakes. Both are supported by Australian Research Council.

Omics/systems biology and cancer cachexia.

PubMed

Gallagher, Iain J; Jacobi, Carsten; Tardif, Nicolas; Rooyackers, Olav; Fearon, Kenneth

2016-06-01

Cancer cachexia is a complex syndrome generated by interaction between the host and tumour cells with a background of treatment effects and toxicity. The complexity of the physiological pathways likely involved in cancer cachexia necessitates a holistic view of the relevant biology. Emergent properties are characteristic of complex systems with the result that the end result is more than the sum of its parts. Recognition of the importance of emergent properties in biology led to the concept of systems biology wherein a holistic approach is taken to the biology at hand. Systems biology approaches will therefore play an important role in work to uncover key mechanisms with therapeutic potential in cancer cachexia. The 'omics' technologies provide a global view of biological systems. Genomics, transcriptomics, proteomics, lipidomics and metabolomics approaches all have application in the study of cancer cachexia to generate systems level models of the behaviour of this syndrome. The current work reviews recent applications of these technologies to muscle atrophy in general and cancer cachexia in particular with a view to progress towards integration of these approaches to better understand the pathology and potential treatment pathways in cancer cachexia. Copyright © 2016. Published by Elsevier Ltd.

Stability of subsystem solutions in agent-based models

NASA Astrophysics Data System (ADS)

Perc, Matjaž

2018-01-01

The fact that relatively simple entities, such as particles or neurons, or even ants or bees or humans, give rise to fascinatingly complex behaviour when interacting in large numbers is the hallmark of complex systems science. Agent-based models are frequently employed for modelling and obtaining a predictive understanding of complex systems. Since the sheer number of equations that describe the behaviour of an entire agent-based model often makes it impossible to solve such models exactly, Monte Carlo simulation methods must be used for the analysis. However, unlike pairwise interactions among particles that typically govern solid-state physics systems, interactions among agents that describe systems in biology, sociology or the humanities often involve group interactions, and they also involve a larger number of possible states even for the most simplified description of reality. This begets the question: when can we be certain that an observed simulation outcome of an agent-based model is actually stable and valid in the large system-size limit? The latter is key for the correct determination of phase transitions between different stable solutions, and for the understanding of the underlying microscopic processes that led to these phase transitions. We show that a satisfactory answer can only be obtained by means of a complete stability analysis of subsystem solutions. A subsystem solution can be formed by any subset of all possible agent states. The winner between two subsystem solutions can be determined by the average moving direction of the invasion front that separates them, yet it is crucial that the competing subsystem solutions are characterised by a proper composition and spatiotemporal structure before the competition starts. We use the spatial public goods game with diverse tolerance as an example, but the approach has relevance for a wide variety of agent-based models.

Interaction centres of pyrimidine nucleotides: cytidine-5'-diphosphate (CDP) and cytidine-5'-triphosphate (CTP) in their reactions with tetramines and Cu(II) ions.

PubMed

Gasowska, A

2005-08-01

The interactions between pyrimidine nucleotides: cytidine-5'-diphosphate (CDP) and cytidine-5'-triphosphate (CTP) and Cu(II) ions, spermine (Spm) and 1,11-diamino-4,8-diazaundecane (3,3,3-tet) have been studied. The composition and stability constants of the complexes formed have been determined by means of the potentiometric method, while the centres of interactions in the ligands have been identified by the spectral methods (UV-Vis, Ultraviolet and Visible spectroscopy; EPR, electron spin resonance; NMR). In the systems without metal, formation of the molecular complexes nucleotide-polyamine with the interaction centres at the endocyclic nitrogen atom of purine ring N3, the oxygen atoms of the phosphate group from the nucleotide and protonated nitrogen atoms of the polyamine have been detected. Significant differences have been found in the metallation between the systems with Spm and with 3,3,3-tet. In the systems with spermine, mainly protonated species are formed with the phosphate group of the nucleotide and deprotonated nitrogen atoms of the polyamine making the coordination centres, while the donor nitrogen atom of the nucleotide N3 is involved in the intramolecular interligand interactions, additionally stabilising the complex. In the systems with 3,3,3-tet, the MLL' type species are formed in which the oxygen atoms of the phosphate group and nitrogen atoms of the polyamine are involved in metallation, whereas the N3 atom from the pyrimidine ring of the nucleotide is located outside the inner coordination sphere of copper ion. The main centre of Cu(II) interaction in the nucleotide, both in the system with Spm and 3,3,3-tet is the phosphate group of the nucleotide.

Licensing of future mobile satellite systems

NASA Technical Reports Server (NTRS)

Lepkowski, Ronald J.

1990-01-01

The regulatory process for licensing mobile satellite systems is complex and can require many years to complete. This process involves frequency allocations, national licensing, and frequency coordination. The regulatory process that resulted in the establishment of the radiodetermination satellite service (RDSS) between 1983 and 1987 is described. In contrast, each of these steps in the licensing of the mobile satellite service (MSS) is taking a significantly longer period of time to complete.

Towards safer, better healthcare: harnessing the natural properties of complex sociotechnical systems.

PubMed

Braithwaite, J; Runciman, W B; Merry, A F

2009-02-01

To sustain an argument that harnessing the natural properties of sociotechnical systems is necessary to promote safer, better healthcare. Triangulated analyses of discrete literature sources, particularly drawing on those from mathematics, sociology, marketing science and psychology. Progress involves the use of natural networks and exploiting features such as their scale-free and small world nature, as well as characteristics of group dynamics like natural appeal (stickiness) and propagation (tipping points). The agenda for change should be set by prioritising problems in natural categories, addressed by groups who self select on the basis of their natural interest in the areas in question, and who set clinical standards and develop tools, the use of which should be monitored by peers. This approach will facilitate the evidence-based practice that most agree is now overdue, but which has not yet been realised by the application of conventional methods. A key to health system transformation may lie under-recognised under our noses, and involves exploiting the naturally-occurring characteristics of complex systems. Current strategies to address healthcare problems are insufficient. Clinicians work best when their expertise is mobilised, and they flourish in groupings of their own interests and preference. Being invited, empowered and nurtured rather than directed, micro-managed and controlled through a hierarchy is preferable.

Towards safer, better healthcare: harnessing the natural properties of complex sociotechnical systems

PubMed Central

Braithwaite, J; Runciman, W B; Merry, A F

2009-01-01

Objectives: To sustain an argument that harnessing the natural properties of sociotechnical systems is necessary to promote safer, better healthcare. Methods: Triangulated analyses of discrete literature sources, particularly drawing on those from mathematics, sociology, marketing science and psychology. Results: Progress involves the use of natural networks and exploiting features such as their scale-free and small world nature, as well as characteristics of group dynamics like natural appeal (stickiness) and propagation (tipping points). The agenda for change should be set by prioritising problems in natural categories, addressed by groups who self select on the basis of their natural interest in the areas in question, and who set clinical standards and develop tools, the use of which should be monitored by peers. This approach will facilitate the evidence-based practice that most agree is now overdue, but which has not yet been realised by the application of conventional methods. Conclusion: A key to health system transformation may lie under-recognised under our noses, and involves exploiting the naturally-occurring characteristics of complex systems. Current strategies to address healthcare problems are insufficient. Clinicians work best when their expertise is mobilised, and they flourish in groupings of their own interests and preference. Being invited, empowered and nurtured rather than directed, micro-managed and controlled through a hierarchy is preferable. PMID:19204130

The status of supergenes in the 21st century: recombination suppression in Batesian mimicry and sex chromosomes and other complex adaptations.

PubMed

Charlesworth, Deborah

2016-01-01

I review theoretical models for the evolution of supergenes in the cases of Batesian mimicry in butterflies, distylous plants and sex chromosomes. For each of these systems, I outline the genetic evidence that led to the proposal that they involve multiple genes that interact during 'complex adaptations', and at which the mutations involved are not unconditionally advantageous, but show advantages that trade-off against some disadvantages. I describe recent molecular genetic studies of these systems and questions they raise about the evolution of suppressed recombination. Nonrecombining regions of sex chromosomes have long been known, but it is not yet fully understood why recombination suppression repeatedly evolved in systems in distantly related taxa, but does not always evolve. Recent studies of distylous plants are tending to support the existence of recombination-suppressed genome regions, which may include modest numbers of genes and resemble recently evolved sex-linked regions. For Batesian mimicry, however, molecular genetic work in two butterfly species suggests a new supergene scenario, with a single gene mutating to produce initial adaptive phenotypes, perhaps followed by modifiers specifically refining and perfecting the new phenotype.

The Major Histocompatibility Complex in Bovines: A Review

PubMed Central

Behl, Jyotsna Dhingra; Verma, N. K.; Tyagi, Neha; Mishra, Priyanka; Behl, Rahul; Joshi, B. K.

2012-01-01

Productivity in dairy cattle and buffaloes depends on the genetic factors governing the production of milk and milk constituents as well as genetic factors controlling disease resistance or susceptibility. The immune system is the adaptive defense system that has evolved in vertebrates to protect them from invading pathogens and also carcinomas. It is remarkable in the sense that it is able to generate an enormous variety of cells and biomolecules which interact with each other in numerous ways to form a complex network that helps to recognize, counteract, and eliminate the apparently limitless number of foreign invading pathogens/molecules. The major histocompatibility complex which is found to occur in all mammalian species plays a central role in the development of the immune system. It is an important candidate gene involved in susceptibility/resistance to various diseases. It is associated with intercellular recognition and with self/nonself discrimination. It plays major role in determining whether transplanted tissue will be accepted as self or rejected as foreign. PMID:23738132

The Origin of Hierarchical Structure Formation in Highly Grafted Symmetric Supramolecular Double-Comb Diblock Copolymers.

PubMed

Hofman, Anton H; Reza, Mehedi; Ruokolainen, Janne; Ten Brinke, Gerrit; Loos, Katja

2017-09-01

Involving supramolecular chemistry in self-assembling block copolymer systems enables design of complex macromolecular architectures that, in turn, could lead to complex phase behavior. It is an elegant route, as complicated and sensitive synthesis techniques can be avoided. Highly grafted double-comb diblock copolymers based on symmetric double hydrogen bond accepting poly(4-vinylpyridine)-block-poly(N-acryloylpiperidine) diblock copolymers and donating 3-nonadecylphenol amphiphiles are realized and studied systematically by changing the molecular weight of the copolymer. Double perpendicular lamellae-in-lamellae are formed in all complexes, independent of the copolymer molecular weight. Temperature-resolved measurements demonstrate that the supramolecular nature and ability to crystallize are responsible for the formation of such multiblock-like structures. Because of these driving forces and severe plasticization of the complexes in the liquid crystalline state, this supramolecular approach can be useful for steering self-assembly of both low- and high-molecular-weight block copolymer systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Spectroscopic study of the benchmark Mn+-H2 complex.

PubMed

Dryza, Viktoras; Poad, Berwyck L J; Bieske, Evan J

2009-05-28

We have recorded the rotationally resolved infrared spectrum of the weakly bound Mn+-H2 complex in the H-H stretch region (4022-4078 cm(-1)) by monitoring Mn+ photodissociation products. The band center of Mn+-H2, the H-H stretch transition, is shifted by -111.8 cm(-1) from the transition of the free H2 molecule. The spectroscopic data suggest that the Mn+-H2 complex consists of a slightly perturbed H2 molecule attached to the Mn+ ion in a T-shaped configuration with a vibrationally averaged intermolecular separation of 2.73 A. Together with the measured Mn+...H2 binding energy of 7.9 kJ/mol (Weis, P.; et al. J. Phys. Chem. A 1997, 101, 2809.), the spectroscopic parameters establish Mn+-H2 as the most thoroughly characterized transition-metal cation-dihydrogen complex and a benchmark for calibrating quantum chemical calculations on noncovalent systems involving open d-shell configurations. Such systems are of possible importance for hydrogen storage applications.

Getting to the core of cadherin complex function in Caenorhabditis elegans.

PubMed

Hardin, Jeff

2015-01-01

The classic cadherin-catenin complex (CCC) mediates cell-cell adhesion in metazoans. Although substantial insights have been gained by studying the CCC in vertebrate tissue culture, analyzing requirements for and regulation of the CCC in vertebrates remains challenging. Caenorhabditis elegans is a powerful system for connecting the molecular details of CCC function with functional requirements in a living organism. Recent data, using an "angstroms to embryos" approach, have elucidated functions for key residues, conserved across all metazoans, that mediate cadherin/β-catenin binding. Other recent work reveals a novel, potentially ancestral, role for the C. elegans p120ctn homologue in regulating polarization of blastomeres in the early embryo via Cdc42 and the partitioning-defective (PAR)/atypical protein kinase C (aPKC) complex. Finally, recent work suggests that the CCC is trafficked to the cell surface via the clathrin adaptor protein complex 1 (AP-1) in surprising ways. These studies continue to underscore the value of C. elegans as a model system for identifying conserved molecular mechanisms involving the CCC.

From Astrochemistry to prebiotic chemistry? An hypothetical approach toward Astrobiology

NASA Astrophysics Data System (ADS)

Le Sergeant d'Hendecourt, L.; Danger, G.

2012-12-01

We present in this paper a general perspective about the evolution of molecular complexity, as observed from an astrophysicist point of view and its possible relation to the problem of the origin of life on Earth. Based on the cosmic abundances of the elements and the molecular composition of our life, we propose that life cannot really be based on other elements. We discuss where the necessary molecular complexity is built-up in astrophysical environments, actually within inter/circumstellar solid state materials known as ``grains''. Considerations based on non-directed laboratory experiments, that must be further extended in the prebiotic domain, lead to the hypothesis that if the chemistry at the origin of life may indeed be a rather universal and deterministic phenomenon, once molecular complexity is installed, the chemical evolution that generated the first prebiotic reactions that involve autoreplication must be treated in a systemic approach because of the strong contingency imposed by the complex local environment(s) and associated processes in which these chemical systems have evolved.

From problem solving to problem definition: scrutinizing the complex nature of clinical practice.

PubMed

Cristancho, Sayra; Lingard, Lorelei; Regehr, Glenn

2017-02-01

In medical education, we have tended to present problems as being singular, stable, and solvable. Problem solving has, therefore, drawn much of medical education researchers' attention. This focus has been important but it is limited in terms of preparing clinicians to deal with the complexity of the 21st century healthcare system in which they will provide team-based care for patients with complex medical illness. In this paper, we use the Soft Systems Engineering principles to introduce the idea that in complex, team-based situations, problems usually involve divergent views and evolve with multiple solution iterations. As such we need to shift the conversation from (1) problem solving to problem definition, and (2) from a problem definition derived exclusively at the level of the individual to a definition derived at the level of the situation in which the problem is manifested. Embracing such a focus on problem definition will enable us to advocate for novel educational practices that will equip trainees to effectively manage the problems they will encounter in complex, team-based healthcare.

The Internet As a Large-Scale Complex System

NASA Astrophysics Data System (ADS)

Park, Kihong; Willinger, Walter

2005-06-01

The Internet may be viewed as a "complex system" with diverse features and many components that can give rise to unexpected emergent phenomena, revealing much about its own engineering. This book brings together chapter contributions from a workshop held at the Santa Fe Institute in March 2001. This volume captures a snapshot of some features of the Internet that may be fruitfully approached using a complex systems perspective, meaning using interdisciplinary tools and methods to tackle the subject area. The Internet penetrates the socioeconomic fabric of everyday life; a broader and deeper grasp of the Internet may be needed to meet the challenges facing the future. The resulting empirical data have already proven to be invaluable for gaining novel insights into the network's spatio-temporal dynamics, and can be expected to become even more important when tryin to explain the Internet's complex and emergent behavior in terms of elementary networking-based mechanisms. The discoveries of fractal or self-similar network traffic traces, power-law behavior in network topology and World Wide Web connectivity are instances of unsuspected, emergent system traits. Another important factor at the heart of fair, efficient, and stable sharing of network resources is user behavior. Network systems, when habited by selfish or greedy users, take on the traits of a noncooperative multi-party game, and their stability and efficiency are integral to understanding the overall system and its dynamics. Lastly, fault-tolerance and robustness of large-scale network systems can exhibit spatial and temporal correlations whose effective analysis and management may benefit from rescaling techniques applied in certain physical and biological systems. The present book will bring together several of the leading workers involved in the analysis of complex systems with the future development of the Internet.

Dynamical analysis of uterine cell electrical activity model.

PubMed

Rihana, S; Santos, J; Mondie, S; Marque, C

2006-01-01

The uterus is a physiological system consisting of a large number of interacting smooth muscle cells. The uterine excitability changes remarkably with time, generally quiescent during pregnancy, the uterus exhibits forceful synchronized contractions at term leading to fetus expulsion. These changes characterize thus a dynamical system susceptible of being studied through formal mathematical tools. Multiple physiological factors are involved in the regulation process of this complex system. Our aim is to relate the physiological factors to the uterine cell dynamic behaviors. Taking into account a previous work presented, in which the electrical activity of a uterine cell is described by a set of ordinary differential equations, we analyze the impact of physiological parameters on the response of the model, and identify the main subsystems generating the complex uterine electrical activity, with respect to physiological data.

Nitric Oxide Synthase and Cyclooxygenase Pathways: A Complex Interplay in Cellular Signaling.

PubMed

Sorokin, Andrey

2016-01-01

The cellular reaction to external challenges is a tightly regulated process consisting of integrated processes mediated by a variety of signaling molecules, generated as a result of modulation of corresponding biosynthetic systems. Both, nitric oxide synthase (NOS) and cyclooxygenase (COX) systems, consist of constitutive forms (NOS1, NOS3 and COX-1), which are mostly involved in housekeeping tasks, and inducible forms (NOS2 and COX-2), which shape the cellular response to stress and variety of bioactive agents. The complex interplay between NOS and COX pathways can be observed at least at three levels. Firstly, products of NOS and Cox systems can mediate the regulation and the expression of inducible forms (NOS2 and COX-2) in response of similar and dissimilar stimulus. Secondly, the reciprocal modulation of cyclooxygenase activity by nitric oxide and NOS activity by prostaglandins at the posttranslational level has been shown to occur. Mechanisms by which nitric oxide can modulate prostaglandin synthesis include direct S-nitrosylation of COX and inactivation of prostaglandin I synthase by peroxynitrite, product of superoxide reaction with nitric oxide. Prostaglandins, conversely, can promote an increased association of dynein light chain (DLC) (also known as protein inhibitor of neuronal nitric oxide synthase) with NOS1, thereby reducing its activity. The third level of interplay is provided by intracellular crosstalk of signaling pathways stimulated by products of NOS and COX which contributes significantly to the complexity of cellular signaling. Since modulation of COX and NOS pathways was shown to be principally involved in a variety of pathological conditions, the dissection of their complex relationship is needed for better understanding of possible therapeutic strategies. This review focuses on implications of interplay between NOS and COX for cellular function and signal integration.

Vibrio Iron Transport: Evolutionary Adaptation to Life in Multiple Environments

PubMed Central

Mey, Alexandra R.; Wyckoff, Elizabeth E.

2015-01-01

SUMMARY Iron is an essential element for Vibrio spp., but the acquisition of iron is complicated by its tendency to form insoluble ferric complexes in nature and its association with high-affinity iron-binding proteins in the host. Vibrios occupy a variety of different niches, and each of these niches presents particular challenges for acquiring sufficient iron. Vibrio species have evolved a wide array of iron transport systems that allow the bacteria to compete for this essential element in each of its habitats. These systems include the secretion and uptake of high-affinity iron-binding compounds (siderophores) as well as transport systems for iron bound to host complexes. Transporters for ferric and ferrous iron not complexed to siderophores are also common to Vibrio species. Some of the genes encoding these systems show evidence of horizontal transmission, and the ability to acquire and incorporate additional iron transport systems may have allowed Vibrio species to more rapidly adapt to new environmental niches. While too little iron prevents growth of the bacteria, too much can be lethal. The appropriate balance is maintained in vibrios through complex regulatory networks involving transcriptional repressors and activators and small RNAs (sRNAs) that act posttranscriptionally. Examination of the number and variety of iron transport systems found in Vibrio spp. offers insights into how this group of bacteria has adapted to such a wide range of habitats. PMID:26658001

Chemokines and Heart Disease: A Network Connecting Cardiovascular Biology to Immune and Autonomic Nervous Systems

PubMed Central

Dusi, Veronica; Ghidoni, Alice; Ravera, Alice; De Ferrari, Gaetano M.; Calvillo, Laura

2016-01-01

Among the chemokines discovered to date, nineteen are presently considered to be relevant in heart disease and are involved in all stages of cardiovascular response to injury. Chemokines are interesting as biomarkers to predict risk of cardiovascular events in apparently healthy people and as possible therapeutic targets. Moreover, they could have a role as mediators of crosstalk between immune and cardiovascular system, since they seem to act as a “working-network” in deep linkage with the autonomic nervous system. In this paper we will describe the single chemokines more involved in heart diseases; then we will present a comprehensive perspective of them as a complex network connecting the cardiovascular system to both the immune and the autonomic nervous systems. Finally, some recent evidences indicating chemokines as a possible new tool to predict cardiovascular risk will be described. PMID:27242392

Par-4-mediated recruitment of Amida to the actin cytoskeleton leads to the induction of apoptosis

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

Boosen, Meike; Vetterkind, Susanne; Koplin, Ansgar

Par-4 (prostate apoptosis response-4) sensitizes cells to apoptotic stimuli, but the exact mechanisms are still poorly understood. Using Par-4 as bait in a yeast two-hybrid screen, we identified Amida as a novel interaction partner, a ubiquitously expressed protein which has been suggested to be involved in apoptotic processes. Complex formation of Par-4 and Amida occurs in vitro and in vivo and is mediated via the C-termini of both proteins, involving the leucine zipper of Par-4. Amida resides mainly in the nucleus but displays nucleo-cytoplasmic shuttling in heterokaryons. Upon coexpression with Par-4 in REF52.2 cells, Amida translocates to the cytoplasm andmore » is recruited to actin filaments by Par-4, resulting in enhanced induction of apoptosis. The synergistic effect of Amida/Par-4 complexes on the induction of apoptosis is abrogated when either Amida/Par-4 complex formation or association of these complexes with the actin cytoskeleton is impaired, indicating that the Par-4-mediated relocation of Amida to the actin cytoskeleton is crucial for the pro-apoptotic function of Par-4/Amida complexes in REF52.2 cells. The latter results in enhanced phosphorylation of the regulatory light chain of myosin II (MLC) as has previously been shown for Par-4-mediated recruitment of DAP-like kinase (Dlk), suggesting that the recruitment of nuclear proteins involved in the regulation of apoptotic processes to the actin filament system by Par-4 represents a potent mechanism how Par-4 can trigger apoptosis.« less

Molecular determinants of orexin receptor-arrestin-ubiquitin complex formation.

PubMed

Jaeger, Werner C; Seeber, Ruth M; Eidne, Karin A; Pfleger, Kevin D G

2014-01-01

The orexin system regulates a multitude of key physiological processes, particularly involving maintenance of metabolic homeostasis. Consequently, there is considerable potential for pharmaceutical development for the treatment of disorders from narcolepsy to metabolic syndrome. It acts through the hormonal activity of two endogenous peptides, orexin A binding to orexin receptors 1 and 2 (OX₁ and OX₂) with similar affinity, and orexin B binding to OX₂ with higher affinity than OX₁ receptors. We have previously revealed data differentiating orexin receptor subtypes with respect to their relative stability in forming orexin receptor-arrestin-ubiquitin complexes measured by BRET. Recycling and cellular signalling distinctions were also observed. Here, we have investigated, using BRET, the molecular determinants involved in providing OX₂ receptors with greater β-arrestin-ubiquitin complex stability. The contribution of the C-terminal tail of the OX receptors was investigated by bulk substitution and site-specific mutagenesis using BRET and inositol phosphate assays. Replacement of the OX₁ receptor C-terminus with that of the OX₂ receptor did not result in the expected gain of function, indicating a role for intracellular domain configuration in addition to primary structure. Furthermore, two out of the three putative serine/threonine clusters in the C-terminus were found to be involved in OX₂ receptor-β-arrestin-ubiquitin complex formation. This study provides fundamental insights into the molecular elements that influence receptor-arrestin-ubiquitin complex formation. Understanding how and why the orexin receptors can be functionally differentiated brings us closer to exploiting these receptors as drug targets. © 2013 The Authors. British Journal of Pharmacology published by John Wiley &. Sons Ltd on behalf of The British Pharmacological Society.

Postural orientation and equilibrium: what do we need to know about neural control of balance to prevent falls?

PubMed

Horak, Fay B

2006-09-01

Postural control is no longer considered simply a summation of static reflexes but, rather, a complex skill based on the interaction of dynamic sensorimotor processes. The two main functional goals of postural behaviour are postural orientation and postural equilibrium. Postural orientation involves the active alignment of the trunk and head with respect to gravity, support surfaces, the visual surround and internal references. Sensory information from somatosensory, vestibular and visual systems is integrated, and the relative weights placed on each of these inputs are dependent on the goals of the movement task and the environmental context. Postural equilibrium involves the coordination of movement strategies to stabilise the centre of body mass during both self-initiated and externally triggered disturbances of stability. The specific response strategy selected depends not only on the characteristics of the external postural displacement but also on the individual's expectations, goals and prior experience. Anticipatory postural adjustments, prior to voluntary limb movement, serve to maintain postural stability by compensating for destabilising forces associated with moving a limb. The amount of cognitive processing required for postural control depends both on the complexity of the postural task and on the capability of the subject's postural control system. The control of posture involves many different underlying physiological systems that can be affected by pathology or sub-clinical constraints. Damage to any of the underlying systems will result in different, context-specific instabilities. The effective rehabilitation of balance to improve mobility and to prevent falls requires a better understanding of the multiple mechanisms underlying postural control.

Amblypygids: Model Organisms for the Study of Arthropod Navigation Mechanisms in Complex Environments?

PubMed Central

Wiegmann, Daniel D.; Hebets, Eileen A.; Gronenberg, Wulfila; Graving, Jacob M.; Bingman, Verner P.

2016-01-01

Navigation is an ideal behavioral model for the study of sensory system integration and the neural substrates associated with complex behavior. For this broader purpose, however, it may be profitable to develop new model systems that are both tractable and sufficiently complex to ensure that information derived from a single sensory modality and path integration are inadequate to locate a goal. Here, we discuss some recent discoveries related to navigation by amblypygids, nocturnal arachnids that inhabit the tropics and sub-tropics. Nocturnal displacement experiments under the cover of a tropical rainforest reveal that these animals possess navigational abilities that are reminiscent, albeit on a smaller spatial scale, of true-navigating vertebrates. Specialized legs, called antenniform legs, which possess hundreds of olfactory and tactile sensory hairs, and vision appear to be involved. These animals also have enormous mushroom bodies, higher-order brain regions that, in insects, integrate contextual cues and may be involved in spatial memory. In amblypygids, the complexity of a nocturnal rainforest may impose navigational challenges that favor the integration of information derived from multimodal cues. Moreover, the movement of these animals is easily studied in the laboratory and putative neural integration sites of sensory information can be manipulated. Thus, amblypygids could serve as model organisms for the discovery of neural substrates associated with a unique and potentially sophisticated navigational capability. The diversity of habitats in which amblypygids are found also offers an opportunity for comparative studies of sensory integration and ecological selection pressures on navigation mechanisms. PMID:27014008

Technology Evaluation for the Big Spring Water Treatment System at the Y-12 National Security Complex, Oak Ridge, Tennessee

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

Becthel Jacobs Company LLC

2002-11-01

The Y-12 National Security Complex (Y-12 Complex) is an active manufacturing and developmental engineering facility that is located on the U.S. Department of Energy (DOE) Oak Ridge Reservation. Building 9201-2 was one of the first process buildings constructed at the Y-12 Complex. Construction involved relocating and straightening of the Upper East Fork Poplar Creek (UEFPC) channel, adding large quantities of fill material to level areas along the creek, and pumping of concrete into sinkholes and solution cavities present within the limestone bedrock. Flow from a large natural spring designated as ''Big Spring'' on the original 1943 Stone & Webster Buildingmore » 9201-2 Field Sketch FS6003 was captured and directed to UEFPC through a drainpipe designated Outfall 51. The building was used from 1953 to 1955 for pilot plant operations for an industrial process that involved the use of large quantities of elemental mercury. Past operations at the Y-12 Complex led to the release of mercury to the environment. Significant environmental media at the site were contaminated by accidental releases of mercury from the building process facilities piping and sumps associated with Y-12 Complex mercury handling facilities. Releases to the soil surrounding the buildings have resulted in significant levels of mercury in these areas of contamination, which is ultimately transported to UEFPC, its streambed, and off-site. Bechtel Jacobs Company LLC (BJC) is the DOE-Oak Ridge Operations prime contractor responsible for conducting environmental restoration activities at the Y-12 Complex. In order to mitigate the mercury being released to UEFPC, the Big Spring Water Treatment System will be designed and constructed as a Comprehensive Environmental Response, Compensation, and Liability Act action. This facility will treat the combined flow from Big Spring feeding Outfall 51 and the inflow now being processed at the East End Mercury Treatment System (EEMTS). Both discharge to UEFPC adjacent to Bldg. 9201-2. The EEMTS treats mercury-contaminated groundwater that collects in sumps in the basement of Bldg. 9201-2. A pre-design study was performed to investigate the applicability of various treatment technologies for reducing mercury discharges at Outfall 51 in support of the design of the Big Spring Water Treatment System. This document evaluates the results of the pre-design study for selection of the mercury removal technology for the treatment system.« less

Sensitivity of the Gravity Recovery and Climate Experiment (GRACE) to the complexity of aquifer systems for monitoring of groundwater

NASA Astrophysics Data System (ADS)

Katpatal, Yashwant B.; Rishma, C.; Singh, Chandan K.

2018-05-01

The Gravity Recovery and Climate Experiment (GRACE) satellite mission is aimed at assessment of groundwater storage under different terrestrial conditions. The main objective of the presented study is to highlight the significance of aquifer complexity to improve the performance of GRACE in monitoring groundwater. Vidarbha region of Maharashtra, central India, was selected as the study area for analysis, since the region comprises a simple aquifer system in the western region and a complex aquifer system in the eastern region. Groundwater-level-trend analyses of the different aquifer systems and spatial and temporal variation of the terrestrial water storage anomaly were studied to understand the groundwater scenario. GRACE and its field application involve selecting four pixels from the GRACE output with different aquifer systems, where each GRACE pixel encompasses 50-90 monitoring wells. Groundwater storage anomalies (GWSA) are derived for each pixel for the period 2002 to 2015 using the Release 05 (RL05) monthly GRACE gravity models and the Global Land Data Assimilation System (GLDAS) land-surface models (GWSAGRACE) as well as the actual field data (GWSAActual). Correlation analysis between GWSAGRACE and GWSAActual was performed using linear regression. The Pearson and Spearman methods show that the performance of GRACE is good in the region with simple aquifers; however, performance is poorer in the region with multiple aquifer systems. The study highlights the importance of incorporating the sensitivity of GRACE in estimation of groundwater storage in complex aquifer systems in future studies.

"Maybe They Don't Even Know That I Exist": Challenges Faced by Family Members and Friends of Patients with Advanced Kidney Disease.

PubMed

O'Hare, Ann M; Szarka, Jackie; McFarland, Lynne V; Vig, Elizabeth K; Sudore, Rebecca L; Crowley, Susan; Reinke, Lynn F; Trivedi, Ranak; Taylor, Janelle S

2017-06-07

Family members and friends of patients with advanced chronic illness are increasingly called on to assist with ever more complex medical care and treatment decisions arising late in the course of illness. Our goal was to learn about the experiences of family members and friends of patients with advanced kidney disease. As part of a study intended to identify opportunities to enhance advance care planning, we conducted semistructured interviews at the Veterans Affairs Puget Sound Health Care System with 17 family members and friends of patients with advanced kidney disease. Interviews were conducted between April of 2014 and May of 2016 and were audiotaped, transcribed, and analyzed inductively using grounded theory to identify emergent themes. The following three themes emerged from interviews with patients' family members and friends: ( 1 ) their roles in care and planning were fluid over the course of the patient's illness, shaped by the patients' changing needs and their readiness to involve those close to them; ( 2 ) their involvement in patients' care was strongly shaped by health care system needs. Family and friends described filling gaps left by the health care system and how their involvement in care and decision-making was at times constrained and at other times expected by providers, depending on system needs; and ( 3 ) they described multiple sources of tension and conflict in their interactions with patients and the health care system, including instances of being pitted against the patient. Interviews with family members and friends of patients with advanced kidney disease provide a window on the complex dynamics shaping their engagement in patients' care, and highlight the potential value of offering opportunities for engagement throughout the course of illness. Copyright © 2017 by the American Society of Nephrology.

Diagnostic reference levels and complexity indices in interventional radiology: a national programme.

PubMed

Ruiz-Cruces, R; Vano, E; Carrera-Magariño, F; Moreno-Rodriguez, F; Soler-Cantos, M M; Canis-Lopez, M; Hernández-Armas, J; Diaz-Romero, F J; Rosales-Espizua, F; Fernandez-Soto, J M; Sanchez-Casanueva, R; Martin-Palanca, A; Perez-Martinez, M; Gil-Agudo, A; Zarca-Diaz, M A; Parra-Osorio, V; Muñoz Ruiz-Canela, J J; Moreno-Sanchez, T; Lopez-Medina, A; Moreno-Saiz, C; Galan-Montenegro, P; Gallego-Beuter, J J; Gonzalez-de-Garay, M; Zapata-Jimenez, J C; Pastor-Vega, J M; Cañete, S

2016-12-01

To propose national diagnostic reference levels (DRLs) for interventional radiology and to evaluate the impact of the procedural complexity on patient doses. Eight interventional radiology units from Spanish hospitals were involved in this project. The participants agreed to undergo common quality control procedures for X-ray systems. Kerma area product (KAP) was collected from a sample of 1,649 procedures. A consensus document established the criteria to evaluate the complexity of seven types of procedures. DRLs were set as the 3rd quartile of KAP values. The KAP (3rd quartile) in Gy cm 2 for the procedures included in the survey were: lower extremity arteriography (n = 784) 78; renal arteriography (n = 37) 107; transjugular hepatic biopsies (THB) (n = 30) 45; biliary drainage (BD) (n = 314) 30; uterine fibroid embolization (UFE) (n = 56) 214; colon endoprostheses (CE) (n = 31) 169; hepatic chemoembolization (HC) (n = 269) 303; femoropopliteal revascularization (FR) (n = 62) 119; and iliac stent (n = 66) 170. The complexity involved the increases in the following KAP factors from simple to complex procedures: THB x4; BD x13; UFE x3; CE x3; HC x5; FR x5 and IS x4. The evaluation of the procedure complexity in patient doses will allow the proper use of DRLs for the optimization of interventional radiology. • National DRLs for interventional procedures have been proposed given level of complexity • For clinical audits, the level of complexity should be taken into account. • An evaluation of the complexity levels of the procedure should be made.

Exploiting the locality of periodic subsystem density-functional theory: efficient sampling of the Brillouin zone.

PubMed

Genova, Alessandro; Pavanello, Michele

2015-12-16

In order to approximately satisfy the Bloch theorem, simulations of complex materials involving periodic systems are made n(k) times more complex by the need to sample the first Brillouin zone at n(k) points. By combining ideas from Kohn-Sham density-functional theory (DFT) and orbital-free DFT, for which no sampling is needed due to the absence of waves, subsystem DFT offers an interesting middle ground capable of sizable theoretical speedups against Kohn-Sham DFT. By splitting the supersystem into interacting subsystems, and mapping their quantum problem onto separate auxiliary Kohn-Sham systems, subsystem DFT allows an optimal topical sampling of the Brillouin zone. We elucidate this concept with two proof of principle simulations: a water bilayer on Pt[1 1 1]; and a complex system relevant to catalysis-a thiophene molecule physisorbed on a molybdenum sulfide monolayer deposited on top of an α-alumina support. For the latter system, a speedup of 300% is achieved against the subsystem DTF reference by using an optimized Brillouin zone sampling (600% against KS-DFT).

Stress, Anxiety, and Immunomodulation: A Pharmacological Analysis.

PubMed

Ray, A; Gulati, K; Rai, N

2017-01-01

Stress and stressful events are common occurrences in our daily lives and such aversive situations bring about complex changes in the biological system. Such stress responses influence the brain and behavior, neuroendocrine and immune systems, and these responses orchestrate to increase or decrease the ability of the organism to cope with such stressors. The brain via expression of complex behavioral paradigms controls peripheral responses to stress and a bidirectional link exists in the modulation of stress effects. Anxiety is a common neurobehavioral correlate of a variety of stressors, and both acute and chronic stress exposure could precipitate anxiety disorders. Psychoneuroimmunology involves interactions between the brain and the immune system, and it is now being increasingly recognized that the immune system could contribute to the neurobehavioral responses to stress. Studies have shown that the brain and its complex neurotransmitter networks could influence immune function, and there could be a possible link between anxiogenesis and immunomodulation during stress. Physiological and pharmacological data have highlighted this concept, and the present review gives an overview of the relationship between stress, anxiety, and immune responsiveness. © 2017 Elsevier Inc. All rights reserved.

Identification and assessment of endocrine disruptors: limitations of in vivo and in vitro assays.

PubMed Central

Zacharewski, T

1998-01-01

It has been suggested that chemicals and complex mixtures capable of modulating the endocrine system may contribute to adverse health, reproduction, and developmental effects in humans and wildlife. These effects include increased incidence of hormone-dependent cancers, compromised reproductive fitness, and abnormal reproductive system development. In response to public concern, regulatory agencies in North America and Europe are formulating potential strategies to systematically test chemicals and complex mixtures for their endocrine-disrupting activities. Because of the complexity of the endocrine system and the number of potential endocrine disruptor targets, a tiered approach involving a complementary battery of short- and long-term in vivo and in vitro assays that assesses both receptor and nonreceptor-mediated mechanisms of action is being considered. However, the available established assays use a limited number of end points, and significant information gaps exist for other potential targets in the endocrine system. In addition to discussing the merits and limitations of the assays that may be adopted, this paper also highlights potential problems associated with the use of a tiered testing strategy. PMID:9599705

Towards sustainable infrastructure management: knowledge-based service-oriented computing framework for visual analytics

NASA Astrophysics Data System (ADS)

Vatcha, Rashna; Lee, Seok-Won; Murty, Ajeet; Tolone, William; Wang, Xiaoyu; Dou, Wenwen; Chang, Remco; Ribarsky, William; Liu, Wanqiu; Chen, Shen-en; Hauser, Edd

2009-05-01

Infrastructure management (and its associated processes) is complex to understand, perform and thus, hard to make efficient and effective informed decisions. The management involves a multi-faceted operation that requires the most robust data fusion, visualization and decision making. In order to protect and build sustainable critical assets, we present our on-going multi-disciplinary large-scale project that establishes the Integrated Remote Sensing and Visualization (IRSV) system with a focus on supporting bridge structure inspection and management. This project involves specific expertise from civil engineers, computer scientists, geographers, and real-world practitioners from industry, local and federal government agencies. IRSV is being designed to accommodate the essential needs from the following aspects: 1) Better understanding and enforcement of complex inspection process that can bridge the gap between evidence gathering and decision making through the implementation of ontological knowledge engineering system; 2) Aggregation, representation and fusion of complex multi-layered heterogeneous data (i.e. infrared imaging, aerial photos and ground-mounted LIDAR etc.) with domain application knowledge to support machine understandable recommendation system; 3) Robust visualization techniques with large-scale analytical and interactive visualizations that support users' decision making; and 4) Integration of these needs through the flexible Service-oriented Architecture (SOA) framework to compose and provide services on-demand. IRSV is expected to serve as a management and data visualization tool for construction deliverable assurance and infrastructure monitoring both periodically (annually, monthly, even daily if needed) as well as after extreme events.

Complex coacervates as a foundation for synthetic underwater adhesives

PubMed Central

Stewart, Russell J.; Wang, Ching Shuen; Shao, Hui

2011-01-01

Complex coacervation was proposed to play a role in the formation of the underwater bioadhesive of the Sandcastle worm (Phragmatopoma californica) based on the polyacidic and polybasic nature of the glue proteins and the balance of opposite charges at physiological pH. Morphological studies of the secretory system suggested the natural process does not involve complex coacervation as commonly defined. The distinction may not be important because electrostatic interactions likely play an important role in formation of the sandcastle glue. Complex coacervation has also been invoked in the formation of adhesive underwater silk fibers of caddisfly larvae and the adhesive plaques of mussels. A process similar to complex coacervation, that is, condensation and dehydration of biopolyelectrolytes through electrostatic associations, seems plausible for the caddisfly silk. This much is clear, the sandcastle glue complex coacervation model provided a valuable blueprint for the synthesis of a biomimetic, waterborne, underwater adhesive with demonstrated potential for repair of wet tissue. PMID:21081223

The complex dynamics of products and its asymptotic properties

PubMed Central

Cristelli, Matthieu; Zaccaria, Andrea; Pietronero, Luciano

2017-01-01

We analyse global export data within the Economic Complexity framework. We couple the new economic dimension Complexity, which captures how sophisticated products are, with an index called logPRODY, a measure of the income of the respective exporters. Products’ aggregate motion is treated as a 2-dimensional dynamical system in the Complexity-logPRODY plane. We find that this motion can be explained by a quantitative model involving the competition on the markets, that can be mapped as a scalar field on the Complexity-logPRODY plane and acts in a way akin to a potential. This explains the movement of products towards areas of the plane in which the competition is higher. We analyse market composition in more detail, finding that for most products it tends, over time, to a characteristic configuration, which depends on the Complexity of the products. This market configuration, which we called asymptotic, is characterized by higher levels of competition. PMID:28520794

Elevation of Plasmin-α2-plasmin Inhibitor Complex Predicts the Diagnosis of Systemic AL Amyloidosis in Patients with Monoclonal Protein.

PubMed

Ishiguro, Kazuya; Hayashi, Toshiaki; Yokoyama, Yoshihiro; Aoki, Yuka; Onodera, Kei; Ikeda, Hiroshi; Ishida, Tadao; Nakase, Hiroshi

2018-03-15

Objective The complication of systemic immunoglobulin light chain (AL) amyloidosis in patients with monoclonal immunoglobulin affects the prognosis, but amyloid deposition in tissues is sometimes difficult to detect due to bleeding tendencies and preferential distributions. However, fibrinolysis is known to be exacerbated in patients with systemic AL amyloidosis specifically. We therefore explored new biomarkers for predicting a diagnosis of systemic AL amyloidosis focusing on coagulation and fibrinolysis markers. Methods We reviewed the clinical features and treatment outcomes of patients with serum monoclonal protein, including primary systemic AL amyloidosis and multiple myeloma (MM), treated at our hospital between January 2008 and December 2014. Results Among several biomarkers, only the serum level of plasmin-α2-plasmin inhibitor complex (PIC) in patients with systemic AL amyloidosis (n=26) at the diagnosis was significantly higher than in patients with MM without AL amyloidosis (n=26) (mean±standard deviation, 3.69±2.82 μg/mL vs. 1.23±0.97 μg/mL, p<0.01). The cut-off for predicting a diagnosis of systemic AL amyloidosis in patients with serum monoclonal protein was 1.72 μg/mL with 84.6% sensitivity and 80.8% specificity. Hepatic involvement resulted in a significantly higher PIC level than no involvement in patients with systemic AL amyloidosis. The serum PIC level was also associated with the hematological response of systemic AL amyloidosis. Conclusion PIC is a useful biomarker for the diagnosis and management of patients with systemic AL amyloidosis.

Risk-Return Relationship in a Complex Adaptive System

PubMed Central

Song, Kunyu; An, Kenan; Yang, Guang; Huang, Jiping

2012-01-01

For survival and development, autonomous agents in complex adaptive systems involving the human society must compete against or collaborate with others for sharing limited resources or wealth, by using different methods. One method is to invest, in order to obtain payoffs with risk. It is a common belief that investments with a positive risk-return relationship (namely, high risk high return and vice versa) are dominant over those with a negative risk-return relationship (i.e., high risk low return and vice versa) in the human society; the belief has a notable impact on daily investing activities of investors. Here we investigate the risk-return relationship in a model complex adaptive system, in order to study the effect of both market efficiency and closeness that exist in the human society and play an important role in helping to establish traditional finance/economics theories. We conduct a series of computer-aided human experiments, and also perform agent-based simulations and theoretical analysis to confirm the experimental observations and reveal the underlying mechanism. We report that investments with a negative risk-return relationship have dominance over those with a positive risk-return relationship instead in such a complex adaptive systems. We formulate the dynamical process for the system's evolution, which helps to discover the different role of identical and heterogeneous preferences. This work might be valuable not only to complexity science, but also to finance and economics, to management and social science, and to physics. PMID:22479416

Risk-return relationship in a complex adaptive system.

PubMed

Song, Kunyu; An, Kenan; Yang, Guang; Huang, Jiping

2012-01-01

For survival and development, autonomous agents in complex adaptive systems involving the human society must compete against or collaborate with others for sharing limited resources or wealth, by using different methods. One method is to invest, in order to obtain payoffs with risk. It is a common belief that investments with a positive risk-return relationship (namely, high risk high return and vice versa) are dominant over those with a negative risk-return relationship (i.e., high risk low return and vice versa) in the human society; the belief has a notable impact on daily investing activities of investors. Here we investigate the risk-return relationship in a model complex adaptive system, in order to study the effect of both market efficiency and closeness that exist in the human society and play an important role in helping to establish traditional finance/economics theories. We conduct a series of computer-aided human experiments, and also perform agent-based simulations and theoretical analysis to confirm the experimental observations and reveal the underlying mechanism. We report that investments with a negative risk-return relationship have dominance over those with a positive risk-return relationship instead in such a complex adaptive systems. We formulate the dynamical process for the system's evolution, which helps to discover the different role of identical and heterogeneous preferences. This work might be valuable not only to complexity science, but also to finance and economics, to management and social science, and to physics.

Developing a framework for qualitative engineering: Research in design and analysis of complex structural systems

NASA Technical Reports Server (NTRS)

Franck, Bruno M.

1990-01-01

The research is focused on automating the evaluation of complex structural systems, whether for the design of a new system or the analysis of an existing one, by developing new structural analysis techniques based on qualitative reasoning. The problem is to identify and better understand: (1) the requirements for the automation of design, and (2) the qualitative reasoning associated with the conceptual development of a complex system. The long-term objective is to develop an integrated design-risk assessment environment for the evaluation of complex structural systems. The scope of this short presentation is to describe the design and cognition components of the research. Design has received special attention in cognitive science because it is now identified as a problem solving activity that is different from other information processing tasks (1). Before an attempt can be made to automate design, a thorough understanding of the underlying design theory and methodology is needed, since the design process is, in many cases, multi-disciplinary, complex in size and motivation, and uses various reasoning processes involving different kinds of knowledge in ways which vary from one context to another. The objective is to unify all the various types of knowledge under one framework of cognition. This presentation focuses on the cognitive science framework that we are using to represent the knowledge aspects associated with the human mind's abstraction abilities and how we apply it to the engineering knowledge and engineering reasoning in design.

Health Systems Research in a Complex and Rapidly Changing Context: Ethical Implications of Major Health Systems Change at Scale.

PubMed

MacGregor, Hayley; Bloom, Gerald

2016-12-01

This paper discusses health policy and systems research in complex and rapidly changing contexts. It focuses on ethical issues at stake for researchers working with government policy makers to provide evidence to inform major health systems change at scale, particularly when the dynamic nature of the context and ongoing challenges to the health system can result in unpredictable outcomes. We focus on situations where 'country ownership' of HSR is relatively well established and where there is significant involvement of local researchers and close ties and relationships with policy makers are often present. We frame our discussion around two country case studies with which we are familiar, namely China and South Africa and discuss the implications for conducting 'embedded' research. We suggest that reflexivity is an important concept for health system researchers who need to think carefully about positionality and their normative stance and to use such reflection to ensure that they can negotiate to retain autonomy, whilst also contributing evidence for health system change. A research process informed by the notion of reflexive practice and iterative learning will require a longitudinal review at key points in the research timeline. Such review should include the convening of a deliberative process and should involve a range of stakeholders, including those most likely to be affected by the intended and unintended consequences of change. © 2016 The Authors Developing World Bioethics Published by John Wiley & Sons Ltd.

Assessing spatial coupling in complex population dynamics using mutual prediction and continuity statistics

USGS Publications Warehouse

Nichols, J.M.; Moniz, L.; Nichols, J.D.; Pecora, L.M.; Cooch, E.

2005-01-01

A number of important questions in ecology involve the possibility of interactions or ?coupling? among potential components of ecological systems. The basic question of whether two components are coupled (exhibit dynamical interdependence) is relevant to investigations of movement of animals over space, population regulation, food webs and trophic interactions, and is also useful in the design of monitoring programs. For example, in spatially extended systems, coupling among populations in different locations implies the existence of redundant information in the system and the possibility of exploiting this redundancy in the development of spatial sampling designs. One approach to the identification of coupling involves study of the purported mechanisms linking system components. Another approach is based on time series of two potential components of the same system and, in previous ecological work, has relied on linear cross-correlation analysis. Here we present two different attractor-based approaches, continuity and mutual prediction, for determining the degree to which two population time series (e.g., at different spatial locations) are coupled. Both approaches are demonstrated on a one-dimensional predator?prey model system exhibiting complex dynamics. Of particular interest is the spatial asymmetry introduced into the model as linearly declining resource for the prey over the domain of the spatial coordinate. Results from these approaches are then compared to the more standard cross-correlation analysis. In contrast to cross-correlation, both continuity and mutual prediction are clearly able to discern the asymmetry in the flow of information through this system.

A Review of Diagnostic Techniques for ISHM Applications

NASA Technical Reports Server (NTRS)

Patterson-Hine, Ann; Biswas, Gautam; Aaseng, Gordon; Narasimhan, Sriam; Pattipati, Krishna

2005-01-01

System diagnosis is an integral part of any Integrated System Health Management application. Diagnostic applications make use of system information from the design phase, such as safety and mission assurance analysis, failure modes and effects analysis, hazards analysis, functional models, fault propagation models, and testability analysis. In modern process control and equipment monitoring systems, topological and analytic , models of the nominal system, derived from design documents, are also employed for fault isolation and identification. Depending on the complexity of the monitored signals from the physical system, diagnostic applications may involve straightforward trending and feature extraction techniques to retrieve the parameters of importance from the sensor streams. They also may involve very complex analysis routines, such as signal processing, learning or classification methods to derive the parameters of importance to diagnosis. The process that is used to diagnose anomalous conditions from monitored system signals varies widely across the different approaches to system diagnosis. Rule-based expert systems, case-based reasoning systems, model-based reasoning systems, learning systems, and probabilistic reasoning systems are examples of the many diverse approaches ta diagnostic reasoning. Many engineering disciplines have specific approaches to modeling, monitoring and diagnosing anomalous conditions. Therefore, there is no "one-size-fits-all" approach to building diagnostic and health monitoring capabilities for a system. For instance, the conventional approaches to diagnosing failures in rotorcraft applications are very different from those used in communications systems. Further, online and offline automated diagnostic applications are integrated into an operations framework with flight crews, flight controllers and maintenance teams. While the emphasis of this paper is automation of health management functions, striking the correct balance between automated and human-performed tasks is a vital concern.

General and craniofacial development are complex adaptive processes influenced by diversity.

PubMed

Brook, A H; O'Donnell, M Brook; Hone, A; Hart, E; Hughes, T E; Smith, R N; Townsend, G C

2014-06-01

Complex systems are present in such diverse areas as social systems, economies, ecosystems and biology and, therefore, are highly relevant to dental research, education and practice. A Complex Adaptive System in biological development is a dynamic process in which, from interacting components at a lower level, higher level phenomena and structures emerge. Diversity makes substantial contributions to the performance of complex adaptive systems. It enhances the robustness of the process, allowing multiple responses to external stimuli as well as internal changes. From diversity comes variation in outcome and the possibility of major change; outliers in the distribution enhance the tipping points. The development of the dentition is a valuable, accessible model with extensive and reliable databases for investigating the role of complex adaptive systems in craniofacial and general development. The general characteristics of such systems are seen during tooth development: self-organization; bottom-up emergence; multitasking; self-adaptation; variation; tipping points; critical phases; and robustness. Dental findings are compatible with the Random Network Model, the Threshold Model and also with the Scale Free Network Model which has a Power Law distribution. In addition, dental development shows the characteristics of Modularity and Clustering to form Hierarchical Networks. The interactions between the genes (nodes) demonstrate Small World phenomena, Subgraph Motifs and Gene Regulatory Networks. Genetic mechanisms are involved in the creation and evolution of variation during development. The genetic factors interact with epigenetic and environmental factors at the molecular level and form complex networks within the cells. From these interactions emerge the higher level tissues, tooth germs and mineralized teeth. Approaching development in this way allows investigation of why there can be variations in phenotypes from identical genotypes; the phenotype is the outcome of perturbations in the cellular systems and networks, as well as of the genotype. Understanding and applying complexity theory will bring about substantial advances not only in dental research and education but also in the organization and delivery of oral health care. © 2014 Australian Dental Association.

A Novel Approach to Primary Cell Culture for Octopus vulgaris Neurons

PubMed Central

Maselli, Valeria; Xu, Fenglian; Syed, Naweed I.; Polese, Gianluca; Di Cosmo, Anna

2018-01-01

Octopus vulgaris is a unique model system for studying complex behaviors in animals. It has a large and centralized nervous system made up of lobes that are involved in controlling various sophisticated behaviors. As such, it may be considered as a model organism for untangling the neuronal mechanisms underlying behaviors—including learning and memory. However, despite considerable efforts, Octopus lags behind its other counterparts vis-à-vis its utility in deciphering the cellular, molecular and synaptic mechanisms underlying various behaviors. This study represents a novel approach designed to establish a neuronal cell culture protocol that makes this species amenable to further exploitation as a model system. Here we developed a protocol that enables dissociation of neurons from two specific Octopus' brain regions, the vertical-superior frontal system and the optic lobes, which are involved in memory, learning, sensory integration and adult neurogenesis. In particular, cells dissociated with enzyme papain and cultured on Poly-D-Lysine-coated dishes with L15-medium and fetal bovine serum yielded high neuronal survival, axon growth, and re-growth after injury. This model was also explored to define optimal culture conditions and to demonstrate the regenerative capabilities of adult Octopus neurons after axotomy. This study thus further underscores the importance of Octopus neurons as a model system for deciphering fundamental molecular and cellular mechanism of complex brain function and underlying behaviors. PMID:29666582

[Current concepts in pathophysiology of CRPS I].

PubMed

Nickel, F T; Maihöfner, C

2010-02-01

Knowledge about the pathophysiology underlying the complex regional pain syndrome (CRPS) has increased over the last years. Classically, CRPS has been considered to be mainly driven by sympathetic dysfunction with sympathetically maintained pain being its major pathogenetic mechanism. Currently, the disease is understood as result of a complex interplay between altered somatosensory, motor, autonomic and inflammatory systems. Peripheral and central sensitization is a common feature in CRPS as in other neuropathic pain syndromes. One important mechanism is the sensitization of spinal dorsal horn cells via activation of postsynaptic NMDA-receptors by chronic C-fiber input. Differential activity of endogenous pain modulating systems may play a pivotal role in the development of CRPS, too. Neuronal plasticity of the somatosensory cortex accounts for central sensory signs. Also the motor system is subject to central adaptive changes in patients with CRPS. Calcitonin-gene related peptide (CGRP) and substance P mediate neurogenic inflammation. Additionally other proinflammatory cytokines involved in the inflammatory response in CRPS have been identified. In terms of the sympathetic nervous system, recent evidence rather points to a sensitization of adrenergic receptors than to increased efferent sympathetic activity. Particularly the expression of alpha (1)-adrenoceptors on nociceptive C-fibers may play a major role. These pathophysiological ideas do not exclude each other. In fact they complement one another. The variety of the involved systems may explain the versatile clinical picture of CRPS. Georg Thieme Verlag KG Stuttgart, New York.

The multiBac protein complex production platform at the EMBL.

PubMed

Berger, Imre; Garzoni, Frederic; Chaillet, Maxime; Haffke, Matthias; Gupta, Kapil; Aubert, Alice

2013-07-11

Proteomics research revealed the impressive complexity of eukaryotic proteomes in unprecedented detail. It is now a commonly accepted notion that proteins in cells mostly exist not as isolated entities but exert their biological activity in association with many other proteins, in humans ten or more, forming assembly lines in the cell for most if not all vital functions.(1,2) Knowledge of the function and architecture of these multiprotein assemblies requires their provision in superior quality and sufficient quantity for detailed analysis. The paucity of many protein complexes in cells, in particular in eukaryotes, prohibits their extraction from native sources, and necessitates recombinant production. The baculovirus expression vector system (BEVS) has proven to be particularly useful for producing eukaryotic proteins, the activity of which often relies on post-translational processing that other commonly used expression systems often cannot support.(3) BEVS use a recombinant baculovirus into which the gene of interest was inserted to infect insect cell cultures which in turn produce the protein of choice. MultiBac is a BEVS that has been particularly tailored for the production of eukaryotic protein complexes that contain many subunits.(4) A vital prerequisite for efficient production of proteins and their complexes are robust protocols for all steps involved in an expression experiment that ideally can be implemented as standard operating procedures (SOPs) and followed also by non-specialist users with comparative ease. The MultiBac platform at the European Molecular Biology Laboratory (EMBL) uses SOPs for all steps involved in a multiprotein complex expression experiment, starting from insertion of the genes into an engineered baculoviral genome optimized for heterologous protein production properties to small-scale analysis of the protein specimens produced.(5-8) The platform is installed in an open-access mode at EMBL Grenoble and has supported many scientists from academia and industry to accelerate protein complex research projects.

A Glutaredoxin·BolA Complex Serves as an Iron-Sulfur Cluster Chaperone for the Cytosolic Cluster Assembly Machinery*♦

PubMed Central

Frey, Avery G.; Palenchar, Daniel J.; Wildemann, Justin D.; Philpott, Caroline C.

2016-01-01

Cells contain hundreds of proteins that require iron cofactors for activity. Iron cofactors are synthesized in the cell, but the pathways involved in distributing heme, iron-sulfur clusters, and ferrous/ferric ions to apoproteins remain incompletely defined. In particular, cytosolic monothiol glutaredoxins and BolA-like proteins have been identified as [2Fe-2S]-coordinating complexes in vitro and iron-regulatory proteins in fungi, but it is not clear how these proteins function in mammalian systems or how this complex might affect Fe-S proteins or the cytosolic Fe-S assembly machinery. To explore these questions, we use quantitative immunoprecipitation and live cell proximity-dependent biotinylation to monitor interactions between Glrx3, BolA2, and components of the cytosolic iron-sulfur cluster assembly system. We characterize cytosolic Glrx3·BolA2 as a [2Fe-2S] chaperone complex in human cells. Unlike complexes formed by fungal orthologs, human Glrx3-BolA2 interaction required the coordination of Fe-S clusters, whereas Glrx3 homodimer formation did not. Cellular Glrx3·BolA2 complexes increased 6–8-fold in response to increasing iron, forming a rapidly expandable pool of Fe-S clusters. Fe-S coordination by Glrx3·BolA2 did not depend on Ciapin1 or Ciao1, proteins that bind Glrx3 and are involved in cytosolic Fe-S cluster assembly and distribution. Instead, Glrx3 and BolA2 bound and facilitated Fe-S incorporation into Ciapin1, a [2Fe-2S] protein functioning early in the cytosolic Fe-S assembly pathway. Thus, Glrx3·BolA is a [2Fe-2S] chaperone complex capable of transferring [2Fe-2S] clusters to apoproteins in human cells. PMID:27519415

Effect of reinforcement learning on coordination of multiangent systems

NASA Astrophysics Data System (ADS)

Bukkapatnam, Satish T. S.; Gao, Greg

2000-12-01

For effective coordination of distributed environments involving multiagent systems, learning ability of each agent in the environment plays a crucial role. In this paper, we develop a simple group learning method based on reinforcement, and study its effect on coordination through application to a supply chain procurement scenario involving a computer manufacturer. Here, all parties are represented by self-interested, autonomous agents, each capable of performing specific simple tasks. They negotiate with each other to perform complex tasks and thus coordinate supply chain procurement. Reinforcement learning is intended to enable each agent to reach a best negotiable price within a shortest possible time. Our simulations of the application scenario under different learning strategies reveals the positive effects of reinforcement learning on an agent's as well as the system's performance.

Assessing Neuro-Systemic & Behavioral Components in the Pathophysiology of Blast-Related Brain Injury

PubMed Central

Kobeissy, Firas; Mondello, Stefania; Tümer, Nihal; Toklu, Hale Z.; Whidden, Melissa A.; Kirichenko, Nataliya; Zhang, Zhiqun; Prima, Victor; Yassin, Walid; Anagli, John; Chandra, Namas; Svetlov, Stan; Wang, Kevin K. W.

2013-01-01

Among the U.S. military personnel, blast injury is among the leading causes of brain injury. During the past decade, it has become apparent that even blast injury as a form of mild traumatic brain injury (mTBI) may lead to multiple different adverse outcomes, such as neuropsychiatric symptoms and long-term cognitive disability. Blast injury is characterized by blast overpressure, blast duration, and blast impulse. While the blast injuries of a victim close to the explosion will be severe, majority of victims are usually at a distance leading to milder form described as mild blast TBI (mbTBI). A major feature of mbTBI is its complex manifestation occurring in concert at different organ levels involving systemic, cerebral, neuronal, and neuropsychiatric responses; some of which are shared with other forms of brain trauma such as acute brain injury and other neuropsychiatric disorders such as post-traumatic stress disorder. The pathophysiology of blast injury exposure involves complex cascades of chronic psychological stress, autonomic dysfunction, and neuro/systemic inflammation. These factors render blast injury as an arduous challenge in terms of diagnosis and treatment as well as identification of sensitive and specific biomarkers distinguishing mTBI from other non-TBI pathologies and from neuropsychiatric disorders with similar symptoms. This is due to the “distinct” but shared and partially identified biochemical pathways and neuro-histopathological changes that might be linked to behavioral deficits observed. Taken together, this article aims to provide an overview of the current status of the cellular and pathological mechanisms involved in blast overpressure injury and argues for the urgent need to identify potential biomarkers that can hint at the different mechanisms involved. PMID:24312074

Assessing neuro-systemic & behavioral components in the pathophysiology of blast-related brain injury.

PubMed

Kobeissy, Firas; Mondello, Stefania; Tümer, Nihal; Toklu, Hale Z; Whidden, Melissa A; Kirichenko, Nataliya; Zhang, Zhiqun; Prima, Victor; Yassin, Walid; Anagli, John; Chandra, Namas; Svetlov, Stan; Wang, Kevin K W

2013-11-21

Among the U.S. military personnel, blast injury is among the leading causes of brain injury. During the past decade, it has become apparent that even blast injury as a form of mild traumatic brain injury (mTBI) may lead to multiple different adverse outcomes, such as neuropsychiatric symptoms and long-term cognitive disability. Blast injury is characterized by blast overpressure, blast duration, and blast impulse. While the blast injuries of a victim close to the explosion will be severe, majority of victims are usually at a distance leading to milder form described as mild blast TBI (mbTBI). A major feature of mbTBI is its complex manifestation occurring in concert at different organ levels involving systemic, cerebral, neuronal, and neuropsychiatric responses; some of which are shared with other forms of brain trauma such as acute brain injury and other neuropsychiatric disorders such as post-traumatic stress disorder. The pathophysiology of blast injury exposure involves complex cascades of chronic psychological stress, autonomic dysfunction, and neuro/systemic inflammation. These factors render blast injury as an arduous challenge in terms of diagnosis and treatment as well as identification of sensitive and specific biomarkers distinguishing mTBI from other non-TBI pathologies and from neuropsychiatric disorders with similar symptoms. This is due to the "distinct" but shared and partially identified biochemical pathways and neuro-histopathological changes that might be linked to behavioral deficits observed. Taken together, this article aims to provide an overview of the current status of the cellular and pathological mechanisms involved in blast overpressure injury and argues for the urgent need to identify potential biomarkers that can hint at the different mechanisms involved.

Therapeutic opportunities of small interfering RNA.

PubMed

Goyal, Bhoomika R; Patel, Mayur M; Soni, Mithil K; Bhadada, Shraddha V

2009-08-01

Formation of small interfering RNA (siRNA) occurs in two steps involving binding of the RNA nucleases to a large double-stranded RNA (dsRNA) and its cleavage into fragments called siRNA. In the second step, these siRNAs join a multinuclease complex, which degrades the homologous single-stranded mRNAs. The delivery of siRNA involves viral- and non-viral-mediated delivery systems; the approaches for chemical modifications have also been developed. It has various therapeutic applications for disorders like cardiovascular diseases, central nervous system (CNS) disorders, cancer, human immunodeficiency virus (HIV), hepatic disorders, etc. The present review gives an overview of the applications of siRNA and their potential for treating many hitherto untreatable diseases.

Autonomic responses to exercise: where is central command?

PubMed

Williamson, J W

2015-03-01

A central command is thought to involve a signal arising in a central area of the brain eliciting a parallel activation of the autonomic nervous system and skeletal muscle contraction during exercise. Although much of the neural circuitry involved in autonomic control has been identified, defining the specific higher brain region(s) serving in a central command capacity has proven more challenging. Investigators have been faced with redundancies in regulatory systems, feedback mechanisms and the complexities ofhuman neural connectivity. Several studies have attempted to address these issues and provide more definitive neuroanatomical information. However, none have clearly answered the question, "where is central command?" Copyright © 2014 Elsevier B.V. All rights reserved.

Assessing the compatibility of the management of standardized procedures with the complexity of a sociotechnical system: case study of a control room in an oil refinery.

PubMed

Saurin, Tarcisio Abreu; Gonzalez, Santiago Sosa

2013-09-01

Although the need for the management of complex socio-technical systems (STS) to be compatible with the nature of those systems is widely recognized, there are few guidelines on how to determine the actual extent of this compatibility. The purpose of this study is to assess how compatible the management of standardized procedures (SPs) is with the nature of a complex STS. To this end, a case study was made of a control room in an oil refinery, involving the following stages: (a) delimitation of the investigated STS; (b) description of the STS according to a set of characteristics of complex STS; (c) application of two types of questionnaires to thirty workers - one of them to assess their perceptions about the applicability of seven principles of SPs management in complex STS and the other to determine their perceptions about the actual use of these principles; and (d) a feedback meeting with workers to discuss the results of the assessment. The assessment is discussed in terms of its limitations, usefulness and ease of use of the data collection and analysis tools. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Classification System for Individualized Treatment of Adult Buried Penis Syndrome.

PubMed

Tausch, Timothy J; Tachibana, Isamu; Siegel, Jordan A; Hoxworth, Ronald; Scott, Jeremy M; Morey, Allen F

2016-09-01

The authors present their experience with reconstructive strategies for men with various manifestations of adult buried penis syndrome, and propose a comprehensive anatomical classification system and treatment algorithm based on pathologic changes in the penile skin and involvement of neighboring abdominal and/or scrotal components. The authors reviewed all patients who underwent reconstruction of adult buried penis syndrome at their referral center between 2007 and 2015. Patients were stratified by location and severity of involved anatomical components. Procedures performed, demographics, comorbidities, and clinical outcomes were reviewed. Fifty-six patients underwent reconstruction of buried penis at the authors' center from 2007 to 2015. All procedures began with a ventral penile release. If the uncovered penile skin was determined to be viable, a phalloplasty was performed by anchoring penoscrotal skin to the proximal shaft, and the ventral shaft skin defect was closed with scrotal flaps. In more complex patients with circumferential nonviable penile skin, the penile skin was completely excised and replaced with a split-thickness skin graft. Complex patients with severe abdominal lipodystrophy required adjacent tissue transfer. For cases of genital lymphedema, the procedure involved complete excision of the lymphedematous tissue, and primary closure with or without a split-thickness skin graft, also often involving the scrotum. The authors' overall success rate was 88 percent (49 of 56), defined as resolution of symptoms without the need for additional procedures. Successful correction of adult buried penis often necessitates an interdisciplinary, multimodal approach. Therapeutic, IV.

Logical Interactions in AN Expanded Space

NASA Astrophysics Data System (ADS)

Tadić, Bosiljka

Understanding the emergent behavior in many complex systems in the physical world and society requires a detailed study of dynamical phenomena occurring and mutually coupled at different scales. The brain processes underlying the social conduct of each, and the emergent social behavior of interacting individuals on a larger scale, represent striking examples of the multiscale complexity. Studies of the human brain, a paradigm of a complex functional system, are enabled by a wealth of brain imaging data that provide clues of how we comprehend space, time, languages, numbers, and differentiate normal from diseased individuals, for example. The social brain, a neural basis for social cognition, represents a dynamically organized part of the brain which is involved in the inference of thoughts, feelings, and intentions going on in the brains of others. Research in this currently unexplored area opens a new perspective on the genesis of the societal organization at different levels and the associated social values...

Assistive Technologies and Issues Relating to Privacy, Ethics and Security

NASA Astrophysics Data System (ADS)

Martin, Suzanne; Bengtsson, Johan E.; Dröes, Rose-Marie

Emerging technologies provide the opportunity to develop innovative sustainable service models, capable of supporting adults with dementia at home. Devices range from simple stand-alone components that can generate a responsive alarm call to complex interoperable systems that even can be remotely controlled. From these complex systems the paradigm of the ubiquitous or ambient smart home has emerged, integrating technology, environmental design and traditional care provision. The service context is often complex, involving a variety of stakeholders and a range of interested agencies. Against this backdrop, as anecdotal evidence and government policies spawn further innovation it is critical that due consideration is given to the potential ethical ramifications at an individual, organisational and societal level. Well-grounded ethical thinking and proactive ethical responses to this innovation are required. Explicit policy and practice should therefore emerge which engenders confidence in existing supported living option schemes for adults with dementia and informs further innovation.

Neuropsychiatric Systemic Lupus Erythematosus Involvement: Towards a Tailored Approach to Our Patients?

PubMed Central

Faria, Raquel; Gonçalves, João; Dias, Rita

2017-01-01

Neuropsychiatric involvement in systemic lupus erythematosus (NPSLE) is a complex condition that remains poorly understood, and includes heterogeneous manifestations involving both the central and peripheral nervous system, with disabling effects. There are several models to improve NPSLE diagnosis when a neurological syndrome is present. In the last couple of years, the growing knowledge of the role of cytokines and antibodies in NPSLE, as well as the development of new functional imaging techniques, has brought some insights into the physiopathology of the disease, but their validation for clinical use remains undetermined. Furthermore, besides the classic clinical approach, a new tool for screening the 19 NPSLE syndromes has also been developed. Regarding NPSLE therapeutics, there is still no evidence-based treatment approach, but some data support the safety of biological medication when classic treatment fails. Despite the tendency to reclassify SLE patients in clinical and immunological subsets, we hope that these data will inspire medical professionals to approach NPSLE in a manner more tailored to the individual patient. PMID:28178431

Neuropsychiatric Systemic Lupus Erythematosus Involvement: Towards a Tailored Approach to Our Patients?

PubMed

Faria, Raquel; Gonçalves, João; Dias, Rita

2017-01-30

Neuropsychiatric involvement in systemic lupus erythematosus (NPSLE) is a complex condition that remains poorly understood, and includes heterogeneous manifestations involving both the central and peripheral nervous system, with disabling effects. There are several models to improve NPSLE diagnosis when a neurological syndrome is present. In the last couple of years, the growing knowledge of the role of cytokines and antibodies in NPSLE, as well as the development of new functional imaging techniques, has brought some insights into the physiopathology of the disease, but their validation for clinical use remains undetermined. Furthermore, besides the classic clinical approach, a new tool for screening the 19 NPSLE syndromes has also been developed. Regarding NPSLE therapeutics, there is still no evidence-based treatment approach, but some data support the safety of biological medication when classic treatment fails. Despite the tendency to reclassify SLE patients in clinical and immunological subsets, we hope that these data will inspire medical professionals to approach NPSLE in a manner more tailored to the individual patient.

Comparison of energy interaction parameters for the complexation of Pr(III) with glutathione reduced (GSH) in absence and presence of Zn(II) in aqueous and aquated organic solvents using 4f?4f transition spectra as PROBE

NASA Astrophysics Data System (ADS)

Singh, Th. David; Sumitra, Ch.; Yaiphaba, N.; Devi, H. Debecca; Devi, M. Indira; Singh, N. Rajmuhon

2005-04-01

The coordination chemistry of glutathione reduced (GSH) is of great importance as it acts as excellent model system for the binding of metal ions. The GSH complexation with metal ions is involved in the toxicology of different metal ions. Its coordination behaviour for soft metal ions and hard metal ions is found different because of the structure of GSH and its different potential binding sites. In our work we have studied two chemically dissimilar metal ions viz. Pr(III), which prefer hard donor site like carboxylic groups and Zn(II) the soft metal ion which prefer peptide-NH and sulphydryl groups. The absorption difference and comparative absorption spectroscopy involving 4f-4f transitions of the heterobimetallic Complexation of GSH with Pr(III) and Zn(II) has been explored in aqueous and aquated organic solvents. The variation in the energy parameters like Slater-Condon ( F K), Racah ( E K) and Lande ( ξ4f), Nephelauxetic parameter ( β) and bonding parameter ( b1/2) are computed to explain the nature of complexation.

A tool for exploring the dynamics of innovative interventions for public health: the critical event card.

PubMed

Figueiro, Ana Claudia; de Araújo Oliveira, Sydia Rosana; Hartz, Zulmira; Couturier, Yves; Bernier, Jocelyne; do Socorro Machado Freire, Maria; Samico, Isabella; Medina, Maria Guadalupe; de Sa, Ronice Franco; Potvin, Louise

2017-03-01

Public health interventions are increasingly represented as complex systems. Research tools for capturing the dynamic of interventions processes, however, are practically non-existent. This paper describes the development and proof of concept process of an analytical tool, the critical event card (CEC), which supports the representation and analysis of complex interventions' evolution, based on critical events. Drawing on the actor-network theory (ANT), we developed and field-tested the tool using three innovative health interventions in northeastern Brazil. Interventions were aimed to promote health equity through intersectoral approaches; were engaged in participatory evaluation and linked to professional training programs. The CEC developing involve practitioners and researchers from projects. Proof of concept was based on document analysis, face-to-face interviews and focus groups. Analytical categories from CEC allow identifying and describing critical events as milestones in the evolution of complex interventions. Categories are (1) event description; (2) actants (human and non-human) involved; (3) interactions between actants; (4) mediations performed; (5) actions performed; (6) inscriptions produced; and (7) consequences for interventions. The CEC provides a tool to analyze and represent intersectoral internvetions' complex and dynamic evolution.

Regenerative life support system research and concepts

NASA Technical Reports Server (NTRS)

1988-01-01

Life support systems that involve recycling of atmospheres, water, food and waste are so complex that models incorporating all the interactions and relationships are vital to design, development, simulations, and ultimately to control of space qualified systems. During early modeling studies, FORTRAN and BASIC programs were used to obtain numerical comparisons of the performance of different regenerative concepts. Recently, models were made by combining existing capabilities with expert systems to establish an Intelligent Design Support Environment for simpliflying user interfaces and to address the need for the engineering aspects. Progress was also made toward modeling and evaluating the operational aspects of closed loop life support systems using Time-step and Dynamic simulations over a period of time. Example models are presented which show the status and potential of developed modeling techniques. For instance, closed loop systems involving algae systeMs for atmospheric purification and food supply augmentation, plus models employing high plants and solid waste electrolysis are described and results of initial evaluations are presented.

In situ application of a cellulose bag and an ion exchanger for differentiation of labile and inert metal species in aquatic systems.

PubMed

Goveia, Danielle; Rosa, André Henrique; Bellin, Iramaia Corrêa; Lobo, Fabiana Aparecida; Fraceto, Leonardo Fernandes; Roveda, José Arnaldo Frutuoso; Romão, Luciane Pimenta Cruz; Dias Filho, Newton Luiz

2008-02-01

This work involved the development and application of a new analytical procedure for in-situ characterization of the lability of metal species in aquatic systems by using a system equipped with a diffusion membrane and cellulose organomodified with p-aminobenzoic acid groups (DM-Cell-PAB). To this end, the DM-Cell-PAB system was prepared by adding cellulose organomodified with p-aminobenzoic acid groups (Cell-PAB) to pre-purified cellulose bags. After the DM-Cell-PAB system was sealed, it was examined in the laboratory. The in-situ application involved immersing the DM-Cell-PAB system in two different rivers, enabling us to study the relative lability of metal species (Cu, Cd, Fe, Mn, and Ni) as a function of time and quantity of exchanger. The procedure is simple and opens up a new perspective for understanding environmental phenomena relating to the complexation, transport, stability, and lability of metal species in aquatic systems rich in organic matter.

Digital control of highly augmented combat rotorcraft

NASA Technical Reports Server (NTRS)

Tischler, Mark B.

1987-01-01

Proposed concepts for the next generation of combat helicopters are to be embodied in a complex, highly maneuverable, multiroled vehicle with avionics systems. Single pilot and nap-of-the-Earth operations require handling qualities which minimize the involvement of the pilot in basic stabilization tasks. To meet these requirements will demand a full authority, high-gain, multimode, multiply-redundant, digital flight-control system. The gap between these requirements and current low-authority, low-bandwidth operational rotorcraft flight-control technology is considerable. This research aims at smoothing the transition between current technology and advanced concept requirements. The state of the art of high-bandwidth digital flight-control systems are reviewed; areas of specific concern for flight-control systems of modern combat are exposed; and the important concepts are illustrated in design and analysis of high-gain, digital systems with a detailed case study involving a current rotorcraft system. Approximate and exact methods are explained and illustrated for treating the important concerns which are unique to digital systems.

Tri-partite complex for axonal transport drug delivery achieves pharmacological effect

PubMed Central

2010-01-01

Background Targeted delivery of pharmaceutical agents into selected populations of CNS (Central Nervous System) neurons is an extremely compelling goal. Currently, systemic methods are generally used for delivery of pain medications, anti-virals for treatment of dermatomal infections, anti-spasmodics, and neuroprotectants. Systemic side effects or undesirable effects on parts of the CNS that are not involved in the pathology limit efficacy and limit clinical utility for many classes of pharmaceuticals. Axonal transport from the periphery offers a possible selective route, but there has been little progress towards design of agents that can accomplish targeted delivery via this intraneural route. To achieve this goal, we developed a tripartite molecular construction concept involving an axonal transport facilitator molecule, a polymer linker, and a large number of drug molecules conjugated to the linker, then sought to evaluate its neurobiology and pharmacological behavior. Results We developed chemical synthesis methodologies for assembling these tripartite complexes using a variety of axonal transport facilitators including nerve growth factor, wheat germ agglutinin, and synthetic facilitators derived from phage display work. Loading of up to 100 drug molecules per complex was achieved. Conjugation methods were used that allowed the drugs to be released in active form inside the cell body after transport. Intramuscular and intradermal injection proved effective for introducing pharmacologically effective doses into selected populations of CNS neurons. Pharmacological efficacy with gabapentin in a paw withdrawal latency model revealed a ten fold increase in half life and a 300 fold decrease in necessary dose relative to systemic administration for gabapentin when the drug was delivered by axonal transport using the tripartite vehicle. Conclusion Specific targeting of selected subpopulations of CNS neurons for drug delivery by axonal transport holds great promise. The data shown here provide a basic framework for the intraneural pharmacology of this tripartite complex. The pharmacologically efficacious drug delivery demonstrated here verify the fundamental feasibility of using axonal transport for targeted drug delivery. PMID:20085661

Identifying Opportunities for Decision Support Systems in Support of Regional Resource Use Planning: An Approach Through Soft Systems Methodology.

PubMed

Zhu; Dale

2000-10-01

/ Regional resource use planning relies on key regional stakeholder groups using and having equitable access to appropriate social, economic, and environmental information and assessment tools. Decision support systems (DSS) can improve stakeholder access to such information and analysis tools. Regional resource use planning, however, is a complex process involving multiple issues, multiple assessment criteria, multiple stakeholders, and multiple values. There is a need for an approach to DSS development that can assist in understanding and modeling complex problem situations in regional resource use so that areas where DSSs could provide effective support can be identified, and the user requirements can be well established. This paper presents an approach based on the soft systems methodology for identifying DSS opportunities for regional resource use planning, taking the Central Highlands Region of Queensland, Australia, as a case study.

Encoding Schemes For A Digital Optical Multiplier Using The Modified Signed-Digit Number Representation

NASA Astrophysics Data System (ADS)

Lasher, Mark E.; Henderson, Thomas B.; Drake, Barry L.; Bocker, Richard P.

1986-09-01

The modified signed-digit (MSD) number representation offers full parallel, carry-free addition. A MSD adder has been described by the authors. This paper describes how the adder can be used in a tree structure to implement an optical multiply algorithm. Three different optical schemes, involving position, polarization, and intensity encoding, are proposed for realizing the trinary logic system. When configured in the generic multiplier architecture, these schemes yield the combinatorial logic necessary to carry out the multiplication algorithm. The optical systems are essentially three dimensional arrangements composed of modular units. Of course, this modularity is important for design considerations, while the parallelism and noninterfering communication channels of optical systems are important from the standpoint of reduced complexity. The authors have also designed electronic hardware to demonstrate and model the combinatorial logic required to carry out the algorithm. The electronic and proposed optical systems will be compared in terms of complexity and speed.

S K-edge XAS and DFT Calculations on Square Planar NiII-thiolate Complexes: Effects of Active and Passive H-bonding

PubMed Central

Dey, Abhishek; Green, Kayla N.; Jenkins, Roxanne M.; Jeffrey, Stephen P.; Darensbourg, Marcetta; Hodgson, Keith O.; Hedman, Britt; Solomon, Edward I.

2008-01-01

S K-edge XAS for a low-spin NiII-thiolate complex shows a 0.2 eV shift to higher pre-edge energy but no change in Ni-S bond covalency upon H-bonding. This is different from the H-bonding effect we observed in high spin FeIII-thiolate complexes where there is a significant decrease in Fe-S bond covalency but no change in energy due to H-bonding (Dey, A.; Okamura, T.-A.; Ueyama, N.; Hedman, B.; Hodgson, K. O.; Solomon, E. I. J. Am. Chem. Soc.; 2005; 127, 12046-12053.). These differences were analyzed using DFT calculations and the results indicate that two different types of H-bonding interactions are possible in metal-thiolate systems. In the high-spin FeIII-thiolate case, the H-bonding involves a thiolate donor orbital which is also involved in bonding with the metal (active), while in the low-spin NiII-thiolate the orbital involved in H-bonding is non-bonding with respect to the M-S bonding (passive). The contributions of active and passive H-bonds to the reduction potential and Lewis acid properties of a metal center are evaluated. PMID:17949080

SK-Edge XAS And DFT Calculations on Square-Planar NiII-Thiolate Complexes: Effects of Active And Passive H-Bonding

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

Dey, A.; Green, K.N.; Jenkins, R.M.

S K-edge XAS for a low-spin Ni{sup II}-thiolate complex shows a 0.2 eV shift to higher pre-edge energy but no change in Ni-S bond covalency upon H-bonding. This is different from the H-bonding effect we observed in high-spin Fe{sup III}-thiolate complexes where there is a significant decrease in Fe-S bond covalency but no change in energy due to H-bonding (Dey, A.; Okamura, T.-A.; Ueyama, N.; Hedman, B.; Hodgson, K. O.; Solomon, E. I. J. Am. Chem. Soc. 2005, 127, 12046-12053). These differences were analyzed using DFT calculations, and the results indicate that two different types of H-bonding interactions are possiblemore » in metal-thiolate systems. In the high-spin Fe{sup III}-thiolate case, the H-bonding involves a thiolate donor orbital which is also involved in bonding with the metal (active), while in the low-spin Ni{sup II}-thiolate, the orbital involved in H-bonding is nonbonding with respect to the M-S bonding (passive). The contributions of active and passive H-bonds to the reduction potential and Lewis acid properties of a metal center are evaluated.« less

Involvement of an Alternative Oxidase in Oxidative Stress and Mycelium-to-Yeast Differentiation in Paracoccidioides brasiliensis ▿ †

PubMed Central

Martins, Vicente P.; Dinamarco, Taisa M.; Soriani, Frederico M.; Tudella, Valéria G.; Oliveira, Sergio C.; Goldman, Gustavo H.; Curti, Carlos; Uyemura, Sérgio A.

2011-01-01

Paracoccidioides brasiliensis is a thermodimorphic human pathogenic fungus that causes paracoccidioidomycosis (PCM), which is the most prevalent systemic mycosis in Latin America. Differentiation from the mycelial to the yeast form (M-to-Y) is an essential step for the establishment of PCM. We evaluated the involvement of mitochondria and intracellular oxidative stress in M-to-Y differentiation. M-to-Y transition was delayed by the inhibition of mitochondrial complexes III and IV or alternative oxidase (AOX) and was blocked by the association of AOX with complex III or IV inhibitors. The expression of P. brasiliensis aox (Pbaox) was developmentally regulated through M-to-Y differentiation, wherein the highest levels were achieved in the first 24 h and during the yeast exponential growth phase; Pbaox was upregulated by oxidative stress. Pbaox was cloned, and its heterologous expression conferred cyanide-resistant respiration in Saccharomyces cerevisiae and Escherichia coli and reduced oxidative stress in S. cerevisiae cells. These results reinforce the role of PbAOX in intracellular redox balancing and demonstrate its involvement, as well as that of other components of the mitochondrial respiratory chain complexes, in the early stages of the M-to-Y differentiation of P. brasiliensis. PMID:21183691

Analysis of DNA interactions using single-molecule force spectroscopy.

PubMed

Ritzefeld, Markus; Walhorn, Volker; Anselmetti, Dario; Sewald, Norbert

2013-06-01

Protein-DNA interactions are involved in many biochemical pathways and determine the fate of the corresponding cell. Qualitative and quantitative investigations on these recognition and binding processes are of key importance for an improved understanding of biochemical processes and also for systems biology. This review article focusses on atomic force microscopy (AFM)-based single-molecule force spectroscopy and its application to the quantification of forces and binding mechanisms that lead to the formation of protein-DNA complexes. AFM and dynamic force spectroscopy are exciting tools that allow for quantitative analysis of biomolecular interactions. Besides an overview on the method and the most important immobilization approaches, the physical basics of the data evaluation is described. Recent applications of AFM-based force spectroscopy to investigate DNA intercalation, complexes involving DNA aptamers and peptide- and protein-DNA interactions are given.

The complexity of gene expression dynamics revealed by permutation entropy

PubMed Central

2010-01-01

Background High complexity is considered a hallmark of living systems. Here we investigate the complexity of temporal gene expression patterns using the concept of Permutation Entropy (PE) first introduced in dynamical systems theory. The analysis of gene expression data has so far focused primarily on the identification of differentially expressed genes, or on the elucidation of pathway and regulatory relationships. We aim to study gene expression time series data from the viewpoint of complexity. Results Applying the PE complexity metric to abiotic stress response time series data in Arabidopsis thaliana, genes involved in stress response and signaling were found to be associated with the highest complexity not only under stress, but surprisingly, also under reference, non-stress conditions. Genes with house-keeping functions exhibited lower PE complexity. Compared to reference conditions, the PE of temporal gene expression patterns generally increased upon stress exposure. High-complexity genes were found to have longer upstream intergenic regions and more cis-regulatory motifs in their promoter regions indicative of a more complex regulatory apparatus needed to orchestrate their expression, and to be associated with higher correlation network connectivity degree. Arabidopsis genes also present in other plant species were observed to exhibit decreased PE complexity compared to Arabidopsis specific genes. Conclusions We show that Permutation Entropy is a simple yet robust and powerful approach to identify temporal gene expression profiles of varying complexity that is equally applicable to other types of molecular profile data. PMID:21176199

Expression of Genes Involved in Iron and Sulfur Respiration in a Novel Thermophilic Crenarchaeon Isolated from Acid-Sulfate-Chloride Geothermal Systems

NASA Astrophysics Data System (ADS)

Kozubal, M.; Macur, R.; Inskeep, W. P.

2007-12-01

Acidic geothermal springs within Yellowstone National Park (YNP) provide an excellent opportunity to study microbial populations and their relationship with geochemical processes such as redox cycling and biomineralization of iron. Fourteen acid-sulfate-chloride (ASC) and acid-sulfate (AS) geothermal springs located in (YNP) have been extensively characterized for aqueous chemistry, solid phase mineral deposition and microbial diversity and distribution. The oxidation of Fe(II) with oxygen as an electron acceptor is exergonic under these conditions, consequently, Fe(II) may be an important electron donor driving primary production in ASC and AS habitats, and products of biomineralization (e.g. Fe[III]-oxides of varying crystallinity and structure, as well as jarosite in some cases) are common in the outflow channels of these environments. Recently, we isolated a novel Metallosphaera-like microorganism (Metallosphaera strain MK1) from an ASC spring in Norris Geyser Basin, YNP. Clone libraries (16S rRNA gene) from multiple sites suggest that microorganisms closely related to strain MK1 (between 98-100 percent similarity) dominate many spring locations between 55-80 C. The in situ abiotic oxidation rate of Fe(II) has been shown to be very slow in these systems and Metallosphaera strain MK1 has been directly implicated in biotic Fe(II) oxidation. Metallosphaera strain MK1 has been submitted for full genome sequencing and is yielding gene sequences related to the terminal oxidases SOXABC and SOXM super-complex. In addition, sequences from a recently characterized terminal oxidase FOX complex involved in Fe(II) and pyrite oxidation from Sulfolobus metallicus have been found in Metallosphaera strain MK1. A protein complex analogous to Metallosphaera sedula has been identified in strain MK1 and this complex has also been expressed in cells grown on pyrite and Fe(II). Other sequences identified in Metallosphaera strain MK1 that are involved in respiration are the TQO complex (thiosulfate:quinone oxidoreductase) related to the Acidianus ambivalens DOXAD complex and a sulfur reductase (SRE) complex related to one found in Sulfolobus solfataricus and Acidianus ambivalens. Here we report on the RNA expression of seven gene sequences from each of the above mentioned complexes for Metallosphaera strain MK1 grown aerobically on pyrite, sulfur, Fe(II)-ferrihydrite, and anaerobically with yeast extract and sulfur. In addition, expression studies are also compared to in situ samples collected from the geothermal Fe-mats.

Biogeography predicts macro‐evolutionary patterning of gestural display complexity in a passerine family

PubMed Central

Miles, Meredith C.; Cheng, Samantha; Fuxjager, Matthew J.

2017-01-01

Gestural displays are incorporated into the signaling repertoire of numerous animal species. These displays range from complex signals that involve impressive and challenging maneuvers, to simpler displays or no gesture at all. The factors that drive this evolution remain largely unclear, and we therefore investigate this issue in New World blackbirds by testing how factors related to a species’ geographical distribution and social mating system predict macro‐evolutionary patterns of display elaboration. We report that species inhabiting temperate regions produce more complex displays than species living in tropical regions, and we attribute this to (i) ecological factors that increase the competitiveness of the social environment in temperate regions, and (ii) different evolutionary and geological contexts under which species in temperate and tropical regions evolved. Meanwhile, we find no evidence that social mating system predicts species differences in display complexity, which is consistent with the idea that gestural displays evolve independently of social mating system. Together, these results offer some of the first insight into the role played by geographic factors and evolutionary context in the evolution of the remarkable physical displays of birds and other vertebrates. PMID:28240772

The Legionella IcmS-IcmW protein complex is important for Dot/Icm-mediated protein translocation.

PubMed

Ninio, Shira; Zuckman-Cholon, Deborah M; Cambronne, Eric D; Roy, Craig R

2005-02-01

The intracellular pathogen Legionella pneumophila can infect and replicate within macrophages of a human host. To establish infection, Legionella require the Dot/Icm secretion system to inject protein substrates directly into the host cell cytoplasm. The mechanism by which substrate proteins are engaged and translocated by the Dot/Icm system is not well understood. Here we show that two cytosolic components of the Dot/Icm secretion machinery, the proteins IcmS and IcmW, play an important role in substrate translocation. Biochemical analysis indicates that IcmS and IcmW form a stable protein complex. In Legionella, the IcmW protein is rapidly degraded in the absence of the IcmS protein. Substrate proteins translocated into mammalian host cells by the Dot/Icm system were identified using the IcmW protein as bait in a yeast two-hybrid screen. It was determined that the IcmS-IcmW complex interacts with these substrates and plays an important role in translocation of these proteins into mammalian cells. These data are consistent with the IcmS-IcmW complex being involved in the recognition and Dot/Icm-dependent translocation of substrate proteins during Legionella infection of host cells.

Numerical Aspects of Atomic Physics: Helium Basis Sets and Matrix Diagonalization

NASA Astrophysics Data System (ADS)

Jentschura, Ulrich; Noble, Jonathan

2014-03-01

We present a matrix diagonalization algorithm for complex symmetric matrices, which can be used in order to determine the resonance energies of auto-ionizing states of comparatively simple quantum many-body systems such as helium. The algorithm is based in multi-precision arithmetic and proceeds via a tridiagonalization of the complex symmetric (not necessarily Hermitian) input matrix using generalized Householder transformations. Example calculations involving so-called PT-symmetric quantum systems lead to reference values which pertain to the imaginary cubic perturbation (the imaginary cubic anharmonic oscillator). We then proceed to novel basis sets for the helium atom and present results for Bethe logarithms in hydrogen and helium, obtained using the enhanced numerical techniques. Some intricacies of ``canned'' algorithms such as those used in LAPACK will be discussed. Our algorithm, for complex symmetric matrices such as those describing cubic resonances after complex scaling, is faster than LAPACK's built-in routines, for specific classes of input matrices. It also offer flexibility in terms of the calculation of the so-called implicit shift, which is used in order to ``pivot'' the system toward the convergence to diagonal form. We conclude with a wider overview.

Orphanin FQ/Nociceptin Interacts with the Basolateral Amygdala Noradrenergic System in Memory Consolidation

ERIC Educational Resources Information Center

Roozendaal, Benno; Lengvilas, Ray; McGaugh, James L.; Civelli, Olivier; Reinscheid, Rainer K.

2007-01-01

Extensive evidence indicates that the basolateral complex of the amygdala (BLA) mediates hormonal and neurotransmitter effects on the consolidation of emotionally influenced memory and that such modulatory influences involve noradrenergic activation of the BLA. As the BLA also expresses a high density of receptors for orphanin FQ/nociceptin…

Immunotherapy for glioblastoma: playing chess, not checkers.

PubMed

Jackson, Christopher M; Lim, Michael

2018-04-24

Patients with glioblastoma (GBM) exhibit a complex state of immune dysfunction involving multiple mechanisms of local, regional, and systemic immune suppression and tolerance. These pathways are now being identified and their relative contributions explored. Delineating how these pathways are interrelated is paramount to effectively implementing immunotherapy for GBM. Copyright ©2018, American Association for Cancer Research.

Fact sheets and slides summarizing Soil and Water Assessment Tool (SWAT) and Integrated Farm Systems Model (IFSM)

USDA-ARS?s Scientific Manuscript database

Water quality models address nonpoint source pollution from agricultural land at a range of scales and complexities and involve a variety of input parameters. It is often difficult for conservationists and stakeholders to understand and reconcile water quality results from different models. However,...

The veA gene of the pine needle pathogen Dothistroma septosporum regulates sporulation and secondary metabolism

USDA-ARS?s Scientific Manuscript database

Fungi possess genetic systems to regulate the expression of genes involved in complex processes such as development and secondary metabolite biosynthesis. The product of the velvet gene veA, first identified and characterized in Aspergillus nidulans, is a key player in the regulation of both of thes...

Mutualism and Antagonism: Ecological Interactions Among Bark Beetles, Mite and Fungi

Treesearch

K.D. Klepzig; J.C. Moser; M.J. Lombardero; M.P. Ayres; R.W. Hofstetter; C.J. Walkinshaw

2001-01-01

Insect-fungal complexes provide challenging and fascinating systems for the study of biotic interactions between plants. plant pathogens, insect vectors and other associated organisms. The types of interactions among these organisms (mutualism. antagonism. parasitism. phoresy. etc.) are as variable as the range of organisms involved (plants, fungi, insects. mites. etc...

The game-theoretic national interstate economic model : an integrated framework to quantify the economic impacts of cyber-terrorist behavior.

DOT National Transportation Integrated Search

2014-12-01

This study suggests an integrated framework to quantify cyber attack impacts on the U.S. airport security system. A cyber attack by terrorists on the U.S. involves complex : strategic behavior by the terrorists because they could plan to invade an ai...

77 FR 32183 - Transmission Planning and Cost Allocation by Transmission Owning and Operating Public Utilities

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-31

... it would not wait for systemic problems to undermine transmission planning before action is taken... that the development of transmission facilities can involve long lead times and complex problems... rather than allowing the problems in transmission planning and cost allocation to continue or to increase...

Challenges to interdisciplinary discourse

Treesearch

David N. Wear

1999-01-01

Many of the world's critical problems involve hu­man interactions with nature and their long-term implications for environmental quality and the sustainability of resource/ecological systems. These problems are complex defined by the collective behaviors of people as well as by the structure and function of ecosystems suggesting that both the social and the...

The Determination of a Useful Frequency for Refreshing Memories for Procedures among a Collegiate Population.

ERIC Educational Resources Information Center

Zambon, Franco

This study sought to determine a useful frequency for refreshing students' memories of complex procedures that involved a formal computer language. Students were required to execute the Microsoft Disc Operating System (MS-DOS) commands for "copy,""backup," and "restore." A total of 126 college students enrolled in six…

Babies' Self-Regulation: Taking a Broad Perspective

ERIC Educational Resources Information Center

Elliot, Enid; Gonzalez-Mena, Janet

2011-01-01

Self-regulation is a complex process that involves coordinating various systems of the body and mind, including feelings. It's not only about emotions but also about cognition. Self-regulation has an impact on social development, influencing how babies and toddlers get along with others. Through self-regulation, babies and toddlers learn to pay…

Identifying Systems of Interaction in Mathematical Engagement

ERIC Educational Resources Information Center

Brown, Bruce J. L.

2014-01-01

Mathematical engagement is a complex process of interaction between the person and the world. This interaction is strongly influenced by the concepts and structure of the mathematical field, by the practical and symbolic tools of mathematics and by the focus of investigation in the world. This paper reports on research that involves a detailed…

Just Working with the Cellular Machine: A High School Game for Teaching Molecular Biology

ERIC Educational Resources Information Center

Cardoso, Fernanda Serpa; Dumpel, Renata; Gomes da Silva, Luisa B.; Rodrigues, Carlos R.; Santos, Dilvani O.; Cabral, Lucio Mendes; Castro, Helena C.

2008-01-01

Molecular biology is a difficult comprehension subject due to its high complexity, thus requiring new teaching approaches. Herein, we developed an interdisciplinary board game involving the human immune system response against a bacterial infection for teaching molecular biology at high school. Initially, we created a database with several…

Channel catfish, Ictalurus punctatus, cysteine proteinases: Cloning, characterization and expression of cathepsin H and L

USDA-ARS?s Scientific Manuscript database

The antigen recognition by the host immune system is a complex biochemical process that requires a battery of enzymes. Cathepsins are one of the enzyme superfamilies involving in antigenic degradations. We observed the up-regulation of cathepsin H and L transcripts during the early stage of Edward...

Improving the LMS Selection Process: Instructor Concerns, Usage and Perceived Value of Online Course Delivery Tools

ERIC Educational Resources Information Center

Laverty, Joseph Packy; Wood, David; Tannehill, Darcy B.; Kohun, Fred; Turchek, John

2012-01-01

Selecting or upgrading a university's Learning Management System (LMS) involves complex decisions concerning curriculum delivery, students, financial commitments, technology and support services, and faculty. The purpose of this paper is to study faculty concerns, usage and perceptions of the instructional value of online course management tools.…

Using Immersive Virtual Environments for Certification

NASA Technical Reports Server (NTRS)

Lutz, R.; Cruz-Neira, C.

1998-01-01

Immersive virtual environments (VEs) technology has matured to the point where it can be utilized as a scientific and engineering problem solving tool. In particular, VEs are starting to be used to design and evaluate safety-critical systems that involve human operators, such as flight and driving simulators, complex machinery training, and emergency rescue strategies.

Salmon and the Adaptive Capacity of Nimiipuu (Nez Perce) Culture to Cope with Change

ERIC Educational Resources Information Center

Colombi, Benedict J.

2012-01-01

Change due to natural disturbances and disasters, population growth and decline, economic crises, and environmental and climate change creates significant cultural challenges. Rapid change and the transformation it brings also involve complex relationships between sovereign tribes, resources, and the global system. This article explores how salmon…

Characterizing a pulse-resolved dosimetry system for complex radiotherapy beams using organic scintillators.

PubMed

Beierholm, Anders R; Ottosson, Rickard O; Lindvold, Lars R; Behrens, Claus F; Andersen, Claus E

2011-05-21

A fast-readout dosimetry system based on fibre-coupled organic scintillators has been developed for the purpose of conducting point measurements of absorbed dose in radiotherapy beams involving high spatial and temporal dose gradients. The system measures the dose for each linac radiation pulse with millimetre spatial resolution. To demonstrate the applicability of the system in complex radiotherapy fields, output factors and per cent depth dose measurements were performed in solid water for a 6 MV photon beam and compared with Monte Carlo simulated doses for square fields down to 0.6 cm × 0.6 cm size. No significant differences between measurements and simulations were observed. The temporal resolution of the system was demonstrated by measuring dose per pulse, beam start-up transients and the quality factor for 6 MV. The precision of dose per pulse measurements was within 2.7% (1 SD) for a 10 cm × 10 cm field at 10 cm depth. The dose per pulse behaviour compared well with linac target current measurements and accumulated dose measurements, and the system was able to resolve transient dose delivery differences between two Varian linac builds. The system therefore shows promise for reference dosimetry and quality assurance of complex radiotherapy treatments.

Complex nonlinear dynamics in the limit of weak coupling of a system of microcantilevers connected by a geometrically nonlinear tunable nanomembrane.

PubMed

Jeong, Bongwon; Cho, Hanna; Keum, Hohyun; Kim, Seok; Michael McFarland, D; Bergman, Lawrence A; King, William P; Vakakis, Alexander F

2014-11-21

Intentional utilization of geometric nonlinearity in micro/nanomechanical resonators provides a breakthrough to overcome the narrow bandwidth limitation of linear dynamic systems. In past works, implementation of intentional geometric nonlinearity to an otherwise linear nano/micromechanical resonator has been successfully achieved by local modification of the system through nonlinear attachments of nanoscale size, such as nanotubes and nanowires. However, the conventional fabrication method involving manual integration of nanoscale components produced a low yield rate in these systems. In the present work, we employed a transfer-printing assembly technique to reliably integrate a silicon nanomembrane as a nonlinear coupling component onto a linear dynamic system with two discrete microcantilevers. The dynamics of the developed system was modeled analytically and investigated experimentally as the coupling strength was finely tuned via FIB post-processing. The transition from the linear to the nonlinear dynamic regime with gradual change in the coupling strength was experimentally studied. In addition, we observed for the weakly coupled system that oscillation was asynchronous in the vicinity of the resonance, thus exhibiting a nonlinear complex mode. We conjectured that the emergence of this nonlinear complex mode could be attributed to the nonlinear damping arising from the attached nanomembrane.

Nanoparticles: Nanoscale Systems for Medical Applications

NASA Astrophysics Data System (ADS)

Wadkins, David Allen

The goal of this project was to develop a series of nano platforms for single cell analysis and drug delivery. Nanoparticles are a promising option to improve our medical therapies by controlling biodistribution and pharmacokinetics of therapeutics. Nanosystems also offer significant opportunity to improve current imaging modalities. The systems developed during this thesis work can be foundations for developing advanced therapies for obesity and improving our fundamental understandings of single cell behavior. The first of the two systems we attempt to create was a drug delivery system that could selectively target adipose tissue to deliver uncoupling agents and drive browning of adipose tissue and associated weight loss. Protonophores have a history of significant toxic side effects in cardiac and neuronal tissues a recently discovered protonophore, but BAM-15, has been shown to have reduced cytotoxicity. We hypothesized that the altered biodistribution of BAM-15 encapsulated in a nanoparticle could provide systemic weight loss with minimized side effects. The second system developed utilized quantum dots to create a fluorescent barcode that could be repeatedly identified using quantitative fluorescent emission readings. This platform would allow for the tracking of individual cells, allowing repeat interrogation across time and space in complex multicellular environments. Ultimately this work demonstrates the process and complexity involved in developing nanoparticulate systems meant to interact with incredibly complex intracellular environments.