bluuebunny/crossref_metadata_2025 huggingface dataset:
The consequences of consumer diversity loss: different answers from different experimental designs
Authors: Byrnes Jarrett E. , Stachowicz John J.
Published: September 2009

Predators are often the most vulnerable group to extinction, yet the consequences of changing predator diversity are poorly understood. One source of confusion has been different experimental designs. The multiple‐predator effects literature typically employs an additive design, while the biodiversity ecosystem function literature typically uses a replacement design. Separately, these designs each detect only a subset of the changes in food web interactions caused by predator loss. Here, we measure the impact of consumer diversity on sessile marine invertebrates using a combination additive–replacement design. We couple this with a meta‐analysis of previous combination experiments. We use these two approaches to explore how each design can detect different types of interactions among predators. We find that, while high diversity does lead to more negative interspecific interactions, the strength of these interactions is often weaker than negative intraspecific interactions caused by increasing the density of a single species alone. We conclude that a hybrid design is the optimal method to explore the mechanisms behind the effects of changing predator diversity. If researchers merely want to know the consequences of changing predator diversity, at a bare minimum, the experimental design must mimic the actual changes in both predator density and diversity in their system of interest. However, only a hybrid design can distinguish the consequences of shifting the balance of interspecific and intraspecific interactions within a community, an issue of great importance when considering both natural diversity loss and pest biocontrol.
Taxonomic, phylogenetic, and environmental trade‐offs between leaf productivity and persistence
Authors: He Jin-Sheng , Wang Xiangping , Flynn Dan F. B. , Wang Liang , Schmid Bernhard , Fang Jingyun
Published: September 2009

Assessing the influence of climate, soil fertility, and species identity on leaf trait relationships is crucial for understanding the adaptations of plants to their environment and for interpreting leaf trait relationships across spatial scales. In a comparative field study of 171 plant species in 174 grassland sites across China, we examined the trade‐offs, defined as negative covariance between two traits, between leaf persistence (leaf mass per area, LMA) and leaf productivity (mass‐based photosynthetic rate,Amass, N and P content, and photosynthetic N use efficiency, PNUE). We asked to which extent these trade‐offs were influenced by: (1) variation among sites within species, decomposed into variation due to climatic and soil variables; (2) variation among species within sites, decomposed into variation among taxonomic, functional, or phylogenetic groups; and (3) the joint contribution of variation among species and sites. We used mixed‐model analysis of covariance to partition bivariate relationships between leaf traits into trade‐off components. We found significant mass‐based persistence–productivity trade‐offs of LMA–Amass, LMA–N, LMA–P, and LMA–PNUE consistent with previous broadscale findings. Overall, (1) variation among sites within species explained 14–23%, (2) variation among species within sites explained 20–34%, and (3) the two together explained 42–63% of the total covariance between leaf traits. Interspecific trade‐offs of LMA–Amass, LMA–N, and LMA–P were stronger than inter‐site ones. A relatively low amount of covariance was explained by climatic and soil variables. However, we found the trade‐offs were stronger for LMA–N and LMA–P at higher precipitation and for LMA–PNUE at greater soil fertility, if displayed by major axis regression, which combined both intra‐ and interspecific variation. Residual trade‐offs within species and sites were weak, suggesting that intraspecific, intra‐site variation in physiology was less important than variation imposed by species identity or environmental differences among sites. Our results from grassland biomes add evidence for the fundamental nature of productivity–persistence trade‐offs in plants. No individual factor emerged as the single major cause for these trade‐offs. Rather, the total covariance between leaf traits was explained by a combination of factors, each contributing a range of explanatory power.
Estimating habitat selection when GPS fix success is less than 100%
Authors: Nielson Ryan M. , Manly Bryan F. J. , McDonald Lyman L. , Sawyer Hall , McDonald Trent L.
Published: September 2009

Inferences about habitat selection by animals derived from sequences of relocations obtained with global positioning system (GPS) collars can be influenced by GPS fix success. Environmental factors such as dense canopy cover or rugged terrain can reduce GPS fix success, making subsequent modeling problematic if fix success depends on the selected habitat. Ignoring failed fix attempts may affect estimates of model coefficients and lead to incorrect conclusions about habitat selection. Here, we present a habitat selection model that accounts for missing locations due to habitat‐induced data losses, called a resource selection function (RSF) for GPS fix success. The model's formulation is similar to adjusting estimates of probability of occupancy when detection is less than 100% in patch occupancy sampling. We demonstrate use of the model with GPS data collected from an adult female mule deer (Odocoileus hemionus) and discuss how to analyze data from multiple animals. In the simulations presented, our habitat selection model was generally unbiased for GPS data sets missing up to 50% of the locations.
A time to grow and a time to die: a new way to analyze the dynamics of size, light, age, and death of tropical trees
Authors: Metcalf C. Jessica E. , Horvitz Carol C. , Tuljapurkar Shripad , Clark Deborah A.
Published: September 2009

In tropical rain forests, rates of forest turnover and tree species' life‐history differences are shaped by the life expectancy of trees and the time taken by seedlings to reach the canopy. These measures are therefore of both theoretical and applied interest. However, the relationship between size, age, and life expectancy is poorly understood. In this paper, we show how to obtain, in a dynamic environment, age‐related population parameters from data on size and light transitions and survival of individuals over single time steps. We accomplish this goal by combining two types of analysis (integral projection modeling and age‐from‐stage analysis for variable environments) in a new way. The method uses an index of crown illumination (CI) to capture the key tree life‐history axis of movement through the light environment. We use this method to analyze data on nine tropical tree species, chosen to sample two main gradients, juvenile recruitment niche (gap/nongap) and adult crown position niche (subcanopy, canopy‐emergent). We validate the method using independent estimates of age and size from growth rings and 14C from some of the same species at the same site and use our results to examine correlations among age‐related population parameters. Finally, we discuss the implications of these new results for life histories of tropical trees.
Depression of belowground respiration rates at simulated high moose population densities in boreal forests
Authors: Persson Inga-Lill , Nilsson Mats B. , Pastor John , Eriksson Tobias , Bergström Roger , Danell Kjell
Published: September 2009

Large herbivores can affect the carbon cycle in boreal forests by changing productivity and plant species composition, which in turn could ultimately alter litter production, nutrient cycling, and the partitioning between aboveground and belowground allocation of carbon. Here we experimentally tested how moose (Alces alces) at different simulated population densities affected belowground respiration rates (estimated as CO2 flux) in young boreal forest stands situated along a site productivity gradient. At high simulated population density, moose browsing considerably depressed belowground respiration rates (24–56% below that of no‐moose controls) except during June, where the difference only was 10%. Moose browsing depressed belowground respiration the most on low‐productivity sites. Soil moisture and temperature did not affect respiration rates. Impact of moose on belowground respiration was closely linked to litter production and followed Michaelis‐Menten dynamics. The main mechanism by which moose decrease belowground respiration rates is likely their effect on photosynthetic biomass (especially decreased productivity of deciduous trees) and total litter production. An increased productivity of deciduous trees along the site productivity gradient causes an unequal effect of moose along the same gradient. The rapid growth of deciduous trees may offer higher resilience against negative effects of moose browsing on litter production and photosynthate allocation to roots.
Do modified habitats have direct or indirect effects on epifauna?
Authors: Marzinelli E. M. , Zagal C. J. , Chapman M. G. , Underwood A. J.
Published: September 2009

Replacing natural habitats with artificial structures such as pier‐pilings, jetties, and seawalls has important consequences to abundances of biota. It is, however, not often known whether these are direct (the novel habitat alters abundances of some species) or indirect (the novel habitat directly alters some aspect of the behavior or ecology of some species, which, in turn, alter abundances of other species). Marine animals in some modified habitats in Sydney Harbour provide experimental opportunities to test hypotheses to distinguish between direct and indirect processes. Covers of bryozoans and hydroids were greater on kelp growing on pilings than on kelp growing on natural reefs. The epifauna may be affected directly by the pilings or indirectly, i.e., the structure affects characteristics of the kelp which, in turn, influence covers of epifauna. Thus, differences in covers of epifauna on kelp can be due to: (1) factors associated with the primary habitats (pilings vs. reefs), (2) differences between characteristics of the kelp found in each habitat, or (3) an interaction between these factors (habitat and/or type of kelp). Kelp were experimentally transplanted between pilings and reefs, demonstrating that properties of the habitat directly affected covers of epifauna, which were not influenced by the type of kelp that grows on pilings or rocky reefs. Manipulative experiments to unconfound multiple components of habitats influencing disturbances to biota are needed to understand human impacts on natural systems.
Scared sick? Predator–pathogen facilitation enhances exploitation of a shared resource
Authors: Ramirez Ricardo A. , Snyder William E.
Published: September 2009

Resource use generally increases with greater consumer diversity, an effect often attributed to resource partitioning. Pathogens and predators are two classes of consumer that exhibit differences in ecologically important traits (e.g., size, resource acquisition strategy, foraging location) that could lead to complementary effects on shared prey/hosts. To examine this possibility, we manipulated diversity among a community of predators and pathogens that together attack an herbivorous beetle, Leptinotarsa decemlineata, and measured resulting effects on herbivore suppression and resulting plant damage. We found that herbivore mortality increased, and plant damage decreased, when more natural enemy species were present. However, closer examination revealed that it was the pairing of predator with pathogen species, rather than greater biodiversity per se, that strengthened herbivore suppression. In this community, predators occur aboveground, attacking herbivore juvenile stages feeding on plant foliage, whereas pathogens occur belowground and attack herbivores pupating in the soil. In a subsequent field experiment, we tracked the emergence of predator–pathogen complementarity throughout the course of beetle development. We found that herbivores exposed to predators aboveground were more susceptible to subsequent pathogen infection belowground, consistent with our observation in the laboratory that predator exposure weakens beetles' immune response. Thus, predators facilitated resource capture by pathogens, perhaps reflecting an inherent conflict for the herbivore in allocating energetic resources toward anti‐predator vs. anti‐pathogen defenses. Our results suggest that predator–pathogen combinations were particularly taxing not because the consumer species partitioned resources among themselves, but instead because they enforced the partitioning of resources internal to prey/host individuals.
Photosynthetic overcompensation under nocturnal warming enhances grassland carbon sequestration
Authors: Wan Shiqiang , Xia Jianyang , Liu Weixing , Niu Shuli
Published: September 2009

A mechanistic understanding of the carbon (C) cycle–climate change feedback is essential for projecting future states of climate and ecosystems. Here we report a novel field mechanism and evidence supporting the hypothesis that nocturnal warming in a temperate steppe ecosystem in northern China can result in a minor C sink instead of a C source as models have predicted. Nocturnal warming increased leaf respiration of two dominant grass species by 36.3%, enhanced consumption of carbohydrates in the leaves (72.2% and 60.5% for sugar and starch, respectively), and consequently stimulated plant photosynthesis by 19.8% in the subsequent days. Our experimental findings confirm previous observations of nocturnal warming stimulating plant photosynthesis through increased draw‐down of leaf carbohydrates at night. The enhancement of plant photosynthesis overcompensated the increased C loss via plant respiration under nocturnal warming and shifted the steppe ecosystem from a minor C source (1.87 g C·m−2·yr−1) to a C sink (21.72 g C·m−2·yr−1) across the three growing seasons from 2006 to 2008. Given greater increases in daily minimum than maximum temperature in many regions, plant photosynthetic overcompensation may partially serve as a negative feedback mechanism for terrestrial biosphere to climate warming.
Spatial dynamics of nesting behavior: Lizards shift microhabitats to construct nests with beneficial thermal properties
Authors: Angilletta Michael J. , Sears Michael W. , Pringle Robert M.
Published: September 2009

Because temperature affects the growth, development, and survival of embryos, oviparous mothers should discriminate carefully among available nesting sites. We combined a radiotelemetric study of animal movements with a spatial mapping of environmental temperatures to test predictions about the nesting behavior of the eastern fence lizard (Sceloporus undulatus). Females made large excursions from their typical home ranges to construct nests in exposed substrates. These excursions appeared to be related solely to nesting because all females returned to forested habitat immediately afterward. On average, <1% (range = 0–8%,n= 19) of the area used by a female during nesting was contained within the area used before and after nesting. The selection of nesting sites matched predictions based on laboratory studies of embryonic performance; specifically, females nested in extremely open habitat at a mean of 6 cm depth. Spatial mapping of soil temperatures revealed that temperatures of nesting areas exceeded those of areas typically used by females, indicating that females preferred to construct warm nests that speed embryonic growth and development. However, this behavior could reduce the survivorship of females because of the need to rapidly navigate unfamiliar and exposed terrain.
Invasive ants alter the phylogenetic structure of ant communities
Authors: Lessard Jean-Philippe , Fordyce James A. , Gotelli Nicholas J. , Sanders Nathan J.
Published: September 2009

Invasive species displace native species and potentially alter the structure and function of ecological communities. In this study, we compared the generic composition of intact and invaded ant communities from 12 published studies and found that invasive ant species alter the phylogenetic structure of native ant communities. Intact ant communities were phylogenetically evenly dispersed, suggesting that competition structures communities. However, in the presence of an invasive ant species, these same communities were phylogenetically clustered. Phylogenetic clustering in invaded communities suggests that invasive species may act as strong environmental filters and prune the phylogenetic tree of native species in a nonrandom manner, such that only a few closely related taxa can persist in the face of a biological invasion. Taxa that were displaced by invasive ant species were evenly dispersed in the phylogeny, suggesting that diversity losses from invasive ant species are not clustered in particular lineages. Collectively, these results suggest that there is strong phylogenetic structuring in intact native ant communities, but the spread of invasive species disassembles those communities above and beyond the effect of simple reductions in diversity.
Implicit Approximation of Neural Network and Applications
Authors: Li Dao-lun , Lu De-tang , Zha Wen-shu
Published: September 2009

It is common practice that one of the reservoir properties is recognized as a complex function of several interrelated factors in neural-network applications used in oil-reservoir studies. Few methods are based on one reservoir property being recognized as a function of time and the spatial locations, which means that the reservoir-property data can be described as a time vector series. It is a great challenge for the artificial neural network to describe a time vector series because the neural network is unable to approximate a multivariate vector function effectively. By combining the principle of implicit curves and surfaces with the neural network, we present a novel way to process the time vector series. The method includes the following steps: mapping data, constructing an explicit function, training the neural network, extracting the isoline, and inverse mapping.

This paper presents an application to predict the isotope-logging data in 2002 with the known data from 2001 and 2003.
Beyond Texas City: The State of Process Safety in the Unionized U.S. Oil Refining Industry
Authors: McQuiston Thomas H. , Lippin Tobi Mae , Bradley-Bull Kristin , Anderson Joseph , Beach Josie , Beevers Gary , Frederick Randy J. , Frederick James , Greene Tammy , Hoffman Thomas , Lefton James , Nibarger Kim , Renner Paul , Ricks Brian , Seymour Thomas , Taylor Ren , Wright Mike
Published: September 2009

The March 2005 British Petroleum (BP) Texas City Refinery disaster provided a stimulus to examine the state of process safety in the U.S. refining industry. Participatory action researchers conducted a nation-wide mail-back survey of United Steelworkers local unions and collected data from 51 unionized refineries. The study examined the prevalence of highly hazardous conditions key to the Texas City disaster, refinery actions to address those conditions, emergency preparedness and response, process safety systems, and worker training. Findings indicate that the key highly hazardous conditions were pervasive and often resulted in incidents or near-misses. Respondents reported worker training was insufficient and less than a third characterized their refineries as very prepared to respond safely to a hazardous materials emergency. The authors conclude that the potential for future disasters plagues the refining industry. In response, they call for effective proactive OSHA regulation and outline ten urgent and critical actions to improve refinery process safety.
The Social Construction of Occupational Health and Safety: Barriers to Environmental-Labor Health Coalitions
Authors: Zoller Heather M.
Published: September 2009

Occupational and environmental health advocates promote the potential of alliances between workers and community members to address shared health problems resulting from industrial processes. Advocates recognize the need to overcome job blackmail, which has successfully pitted these groups against one another by threatening job loss in the face of calls for improved standards. This strategic form of issue management represents a dualism between good health and clean environments on one hand and jobs and tax bases on the other. The author argues that overcoming job blackmail requires attention not only to this dualism, but to the broader social construction of occupational and environmental health. The article describes a series of oppositional constructions, in both strategic organizational rhetoric and everyday cultural discourse, which reinforces job blackmail and impedes the development of solidarity among workers, neighbors, and environmental advocates. These dualisms polarize our views of work and environment, science, and social identity, thereby producing barriers to coalition formation. Understanding these reifications helps to build an activist agenda and identify potential resources for organizing to overcome these barriers.
“It Will Take Persistence”: The Dynamics of a University-Community Partnership to Sustain the New England Worker Health and Safety Movement
Authors: Slatin Craig , Fleishman Jane , Morse Paul , Levenstein Charles
Published: September 2009

The New England Consortium (TNEC) is a university-community partnership that since 1987 has delivered health and safety training for hazardous waste operations and emergency response (HAZWOPER) workers. Through two decades of the relative loss of power by the labor and environmental movements and subsequent reductions in state support for worker health and safety, this selective history of TNEC demonstrates its ability to sustain a worker health and safety movement in New England. The evolution of TNEC's partnership process and the principles and policies by which it operates have helped to resolve several critical conflicts and strengthen its working relationships. Partnership dynamics are explored within their political and economic contexts and the need of member organizations to balance fiscal solvency with political objectives.
Who's Sick at School: Linking Poor School Conditions and Health Disparities for Boston's Children
Authors: Graham Tolle , Zotter Jean , Camacho Marlene
Published: September 2009

A recent review of student asthma rates and environmental audits of school buildings suggests that schools with poor indoor air quality have higher-than-average rates of asthma. Many Boston Public School (BPS) children and staff are learning and working in poor indoor environmental conditions that not only can exacerbate asthma, but also lead to other problems ranging from allergies and sinus infections to adverse academic performance [1]. The Boston Urban Asthma Coalition (BUAC) conducted a preliminary analysis of 2004–05 childhood asthma rates for BPS students and compared them to the 2004–05 environmental audits of the top 10 schools with environmental problems. This analysis suggests that schools with the highest rates of leaks, mold, and pest infestations also have higher-than-average asthma rates for children.
Future Profitability, Operating Cash Flows, and Market Valuations Associated with Offshoring Arrangements of Technology Jobs
Authors: Dunn Kimberly , Kohlbeck Mark , Magilke Matthew
Published: September 2009

ABSTRACT: We investigate profitability, operating cash flows, and value relevance associated with offshoring arrangements of technology-oriented jobs. Offshoring is the business practice of moving substantial portions of a firm's business operations (and jobs) to another country usually to take advantage of lower labor costs or other production factors in developing countries. Offshoring carries social costs as local jobs are lost which may limit realization of benefits. We find that firms that offshore technology-oriented jobs report greater earnings and operating cash flows following an offshoring event as the relative size of the offshoring arrangement increases. Consistent with these results, the market only values offshoring beyond the impact recognized in the financial statements for larger offshoring arrangements. A valuation discount actually exists for smaller offshoring arrangements suggesting either (1) costs exceed potential benefits or (2) the perception that benefits are only realized through economies of scale. We document both benefits and costs that are important for those firms considering offshoring arrangements and their stakeholders.
Assurance on XBRL-Related Documents: The Case of United Technologies Corporation
Authors: Boritz J. Efrim , No Won Gyun
Published: September 2009

ABSTRACT: The eXtensible Business Reporting Language (XBRL) was developed to provide financial information users with a standardized method to prepare, publish, and exchange business information in digital format. XBRL is being used around the world for financial reporting and government e-filings. Although there has been growing awareness about assurance issues related to the use of XBRL, current audit practices and standards fall short of providing the needed guidance for the provision of assurance on XBRL-Related Documents. In this paper, we report on a mock assurance engagement that we conducted on the XBRL-Related Documents of United Technologies Corporation's 10-Q for the third quarter of 2005 and repeated on its 10-Q for the third quarter of 2008 to identify the issues that companies and auditors might encounter if they are requested to provide assurance on XBRL-Related Documents. We describe the assurance framework applied in the mock assurance engagement, present the findings from the examination process, and discuss future research opportunities associated with XBRL documents assurance.
The propagator for step potential and mass using path decomposition method
Authors: Laissaoui Aïda , Chetouani Lyazid
Published: September 2009

The one-dimensional path decomposition expression for the step potential and mass is formulated. The propagator is analytically determined and the limiting case m
1; m
2 → m is exactly obtained.
A Novel Interval Arithmetic Approach for Solving Differential-Algebraic Equations with ValEncIA-IVP
Authors: Rauh Andreas , Brill Michael , Günther Clemens
Published: September 2009

A Novel Interval Arithmetic Approach for Solving Differential-Algebraic Equations with ValEncIA-IVP

The theoretical background and the implementation of a new interval arithmetic approach for solving sets of differential-algebraic equations (DAEs) are presented. The proposed approach computes guaranteed enclosures of all reachable states of dynamical systems described by sets of DAEs with uncertainties in both initial conditions and system parameters. The algorithm is based on ValEncIA-IVP, which has been developed recently for the computation of verified enclosures of the solution sets of initial value problems for ordinary differential equations. For the application to DAEs, ValEncIA-IVP has been extended by an interval Newton technique to solve nonlinear algebraic equations in a guaranteed way. In addition to verified simulation of initial value problems for DAE systems, the developed approach is applicable to the verified solution of the so-called inverse control problems. In this case, guaranteed enclosures for valid input signals of dynamical systems are determined such that their corresponding outputs are consistent with prescribed time-dependent functions. Simulation results demonstrating the potential of ValEncIA-IVP for solving DAEs in technical applications conclude this paper. The selected application scenarios point out relations to other existing verified simulation techniques for dynamical systems as well as directions for future research.
Interval Analysis for Certified Numerical Solution of Problems in Robotics
Authors: Merlet Jean-Pierre
Published: September 2009

Interval Analysis for Certified Numerical Solution of Problems in Robotics

Interval analysis is a relatively new mathematical tool that allows one to deal with problems that may have to be solved numerically with a computer. Examples of such problems are system solving and global optimization, but numerous other problems may be addressed as well. This approach has the following general advantages: (a) it allows to find solutions of a problem only within some finite domain which make sense as soon as the unknowns in the problem are physical parameters; (b) numerical computer round-off errors are taken into account so that the solutions are guaranteed; (c) it allows one to take into account the uncertainties that are inherent to a physical system. Properties (a) and (c) are of special interest in robotics problems, in which many of the variables are parameters that are measured (i.e., known only up to some bounded errors) while the modeling of the robot is based on parameters that are submitted to uncertainties (e.g., because of manufacturing tolerances). Taking into account these uncertainties is essential for many robotics applications such as medical or space robotics for which safety is a crucial issue. A further inherent property of interval analysis that is of interest for robotics problems is that this approach allows one to deal with theuncertaintiesthat are unavoidable in robotics. Although the basic principles of interval analysis are easy to understand and to implement, this approach will be efficient only if the right heuristics are used and if the problem at hand is formulated appropriately. In this paper we will emphasize various robotics problems that have been solved with interval analysis, many of which are currently beyond the reach of other mathematical approaches.
Reliable Robust Path Planning with Application to Mobile Robots
Authors: Pepy Romain , Kieffer Michel , Walter Eric
Published: September 2009

Reliable Robust Path Planning with Application to Mobile Robots

This paper is devoted to path planning when the safety of the system considered has to be guaranteed in the presence of bounded uncertainty affecting its model. A new path planner addresses this problem by combining Rapidly-exploring Random Trees (RRT) and a set representation of uncertain states. An idealized algorithm is presented first, before a description of one of its possible implementations, where compact sets are wrapped into boxes. The resulting path planner is then used for nonholonomic path planning in robotics.
Nonlinear Stabilizing Control of an Uncertain Bioprocess Model
Authors: Dimitrova Neli , Krastanov Mikhail
Published: September 2009

Nonlinear Stabilizing Control of an Uncertain Bioprocess Model

In this paper we consider a nonlinear model of a biological wastewater treatment process, based on two microbial populations and two substrates. The model, described by a four-dimensional dynamic system, is known to be practically verified and reliable. First we study the equilibrium points of the open-loop system, their stability and local bifurcations with respect to the control variable. Further we propose a feedback control law for asymptotic stabilization of the closed-loop system towards a previously chosen operating point. A numerical extremum seeking algorithm is designed to stabilize the dynamics towards the maximum methane output flow rate in the presence of coefficient uncertainties. Computer simulations in Maple are reported to illustrate the theoretical results.
Derivation of Physically Motivated Constraints for Efficient Interval Simulations Applied to the Analysis of Uncertain Dynamical Systems
Authors: Freihold Mareile , Hofer Eberhard
Published: September 2009

Derivation of Physically Motivated Constraints for Efficient Interval Simulations Applied to the Analysis of Uncertain Dynamical Systems

Interval arithmetic techniques such as ValEncIA-IVP allow calculating guaranteed enclosures of all reachable states of continuous-time dynamical systems with bounded uncertainties of both initial conditions and system parameters. Considering the fact that, in naive implementations of interval algorithms, overestimation might lead to unnecessarily conservative results, suitable consistency tests are essential to obtain the tightest possible enclosures. In this contribution, a general framework for the use of constraints based on physically motivated conservation properties is presented. The use of these constraints in verified simulations of dynamical systems provides a computationally efficient procedure which restricts the state enclosures to regions that are physically meaningful. A branch and prune algorithm is modified to a consistency test, which is based on these constraints. Two application scenarios are studied in detail. First, the total energy is employed as a conservation property for the analysis of mechanical systems. It is shown that conservation properties, such as the energy, are applicable to any Hamiltonian system. The second scenario is based on constraints that are derived from decoupling properties, which are considered for a high-dimensional compartment model of granulopoiesis in human blood cell dynamics.
Verified Solution Method for Population Epidemiology Models with Uncertainty
Authors: Enszer Joshua , Stadtherr Mark
Published: September 2009

Verified Solution Method for Population Epidemiology Models with Uncertainty

Epidemiological models can be used to study the impact of an infection within a population. These models often involve parameters that are not known with certainty. Using a method for verified solution of nonlinear dynamic models, we can bound the disease trajectories that are possible for given bounds on the uncertain parameters. The method is based on the use of an interval Taylor series to represent dependence on time and the use of Taylor models to represent dependence on uncertain parameters and/or initial conditions. The use of this method in epidemiology is demonstrated using the SIRS model, and other variations of Kermack-McKendrick models, including the case of time-dependent transmission.
Introductory: Gombrich's Struggle Against Metaphysics
Authors: Bakoš Ján
Published: September 2009

Introductory: Gombrich's Struggle Against Metaphysics

The paper deals with E. H. Gombrich's lifelong polemics against metaphysics in art history and the humanities. They began in 1937 and continued up until his final (posthumous) book The Preference for the Primitives. Analyzing the "fallacies" and "pitfalls" resulting from metaphysical collectivism, essentialism, expressionism, holism and relativism such as a "belief in hypostatized collective personalities" and "style as a super-artist" or "physiognomic fallacy", Gombrich also unmasked their ideological implications. He first targeted nationalism and racialism, then the perils of totalitarianism and finally all forms of relativism. Gombrich's plea for the universality of the "canon of excellence" can be regarded not only as a defence of humanism but also as a form of apology for the values of Western liberal democratic society.
Form of Thought and Presentational Gesture in Karl Popper and E. H. Gombrich
Authors: Schneider Norbert
Published: September 2009

Form of Thought and Presentational Gesture in Karl Popper and E. H. Gombrich

The paper deals with common elements and differences in Popper and Gombrich, especially concerning their forms of thought and presentational gesture. Among others it considers the model of common sense which was basal for both of them as well as the similarities of searchlight theory (Popper) and some postulates of Gestalt psychology (Gombrich). At the end it analyses their approaches to historiography with special focusing on Gombrich's comments on the concept of social history of art.
Gombrich and the Problem of Relativity of Vision
Authors: Kesner Ladislav
Published: September 2009

Gombrich and the Problem of Relativity of Vision

The essay argues that Ernst Gombrich's views are relevant to the critical examination of the notion of the relativity and historicity of vision which has been widely accepted as one of the central axioms shared by visual studies, art history and film studies.
E. H. Gombrich's Adoption of the Formula form Follows Function: A Case of Mistaken Identity?
Authors: Michl Jan
Published: September 2009

E. H. Gombrich's Adoption of the Formula form Follows Function: A Case of Mistaken Identity?

This article is a longer note on what is a minor problem in the oeuvre of a great art historian. Its theme is E. H. Gombrich's use of the formula form follows function as the summary of his commonsense approach to the problem of style change. Although I am not sure how interesting this inquiry is in an art historical context, from the perspective of my own field of design history and of modernist design theory, Gombrich's adoption of the formula constitutes an intriguing problem.
Can thiol compounds be used as biomarkers of aquatic ecosystem contamination by cadmium?
Authors: Kovářová Jana , Svobodová Zdeňka
Published: September 2009

Can thiol compounds be used as biomarkers of aquatic ecosystem contamination by cadmium?

Due to anthropogenic activities, heavy metals still represent a threat for various trophic levels. If aquatic animals are exposed to heavy metals we can obviously observe considerable toxicity. It is well known that an organism affected by cadmium (Cd) synthesize low molecular mass thiol compounds rich in cysteine (Cys), such as metallothioneins (MT) and glutathione (GSH/GSSG). The aim of this study was to summarize the effect of Cd on level of thiol compounds in aquatic organisms, and evaluate that the concentrations of thiol compounds are effective indicators of Cd water pollution and explain their potential use in biomonitoring applications.
Recent Advances in Synthetic Bioelastomers
Authors: Shi Rui , Chen Dafu , Liu Quanyong , Wu Yan , Xu Xiaochuan , Zhang Liqun , Tian Wei
Published: September 2009

This article reviews the degradability of chemically synthesized bioelastomers, mainly designed for soft tissue repair. These bioelastomers involve biodegradable polyurethanes, polyphosphazenes, linear and crosslinked poly(ether/ester)s, poly(ε-caprolactone) copolymers, poly(1,3-trimethylene carbonate) and their copolymers, poly(polyol sebacate)s, poly(diol-citrates) and poly(ester amide)s. The in vitro and in vivo degradation mechanisms and impact factors influencing degradation behaviors are discussed. In addition, the molecular designs, synthesis methods, structure properties, mechanical properties, biocompatibility and potential applications of these bioelastomers were also presented.
A New Look at the Most Successful Prodrugs for Active Vitamin D (D Hormone): Alfacalcidol and Doxercalciferol
Authors: Kubodera Noboru
Published: September 2009

Alfacalcidol (1α-hydroxyvitamin D3) has been widely used since 1981 as a prodrug for calcitriol (1α,25-dihydroxyvitamin D3) in the treatment of hypocalcemia, chronic renal failure, hypoparathyroidism and osteoporosis. More recently, doxercalciferol (1α-hydroxyvitamin D2) has been used since 1999 as a prodrug for 1α,25-dihydroxyvitamin D2 for the treatment of secondary hyperparathyroidism. Currently, six forms of vitamin D are known. They range from vitamin D2 to vitamin D7 and are distinguished by their differing side chains. Only vitamin D2 and vitamin D3 have been found to be biologically active based on the elucidation of activation pathways. Alfacalcidol and osteoporosis/doxercalciferol and secondary hyperparathyroidism are discussed, with a new look at old compounds including their practical syntheses.
A weed–crop complex in sorghum: The dynamics of genetic diversity in a traditional farming system
Authors: Barnaud Adeline , Deu Monique , Garine Eric , Chantereau Jacques , Bolteu Justin , Koïda Esaei Ouin , McKey Doyle , Joly Hélène I.
Published: September 2009

Despite the major ecological and economic impacts of gene flow between domesticated plants and their wild relatives, many aspects of the process, particularly the relative roles of natural and human selection in facilitating or constraining gene flow, are still poorly understood. We developed a multidisciplinary approach, involving both biologists and social scientists, to investigate the dynamics of genetic diversity of a sorghum weed–crop complex in a village of Duupa farmers in northern Cameroon. Farmers distinguish a gradient from weedy morphotypes (naa baa see, haariya, and genkiya) to domesticated morphotypes; haariya and genkiya have intermediate morphological traits. We investigated the pattern of diversity in this complex using both morphological and genetic data. Our biological results are interpreted in the light of data on farmers’ taxonomy and practices such as spatial pattern of planting and plant selection. Both morphological and genetic data are congruent with farmers’ taxonomy and confirm the introgressed status of intermediate weedy morphotypes. Farmers actively select against weedy morphotypes, but several practices unconsciously favor gene flow. Furthermore, haariya and genkiya may facilitate introgression between naa baa see and domesticated morphotypes by virtue of their intermediate flowering period and their mode of management by farmers.
Nondestructive estimation of anthocyanins and chlorophylls in anthocyanic leaves
Authors: Gitelson Anatoly A. , Chivkunova Olga B. , Merzlyak Mark N.
Published: September 2009

The anthocyanin and chlorophyll contents in leaves provide valuable information about the physiological status of plants. Thus, there is a need for accurate, efficient, and practical methodologies to estimate these biochemical parameters of vegetation. In this study, we tested the performance and accuracy of several nondestructive, reflectance‐based techniques for estimating anthocyanin and chlorophyll contents in leaves of four unrelated species, European hazel (Corylus avellana), Siberian dogwood (Cornus alba =Swida alba), Norway maple (Acer platanoides), and Virginia creeper (Parthenocissus quinquefolia), with widely variable pigment content and composition. An anthocyanin reflectance index, which uses reflectances in the green and red edge spectral bands, and a modified anthocyanin reflectance index, employing, in addition, the near‐infrared (NIR) band, were able to accurately estimate leaf anthocyanin for all species taken together with no reparameterization of algorithms. Total chlorophyll content was accurately estimated by a red edge chlorophyll index that uses spectral bands in the red edge and the NIR. These approaches can be used to estimate anthocyanin and chlorophyll nondestructively and allow the development of simple handheld field instrumentation.
The evolutionary origin of a second radiation of annual Castilleja (Orobanchaceae) species in South America: The role of long distance dispersal and allopolyploidy
Authors: Tank David C. , Olmstead Richard G.
Published: September 2009

Considerable attention has been directed toward understanding the wide gaps in range that are common among many groups of closely related organisms. By placing their biology and geography in a phylogenetic context, we may gain a broader knowledge of the series of historical events that have led to present species distributions. In addition to the North American annuals, a second radiation of annual Castilleja species is in Andean Peru and central Chile. Phylogenetic analyses of chloroplast and nuclear DNA regions revealed a complex history for the origin and diversification of annual Castilleja species in South America. In addition to at least three independent long‐distance dispersal events from North America, allopolyploidy has played a significant role in this disjunct radiation. Only C. attenuata occurs in both California and South America, and these results support its recent arrival to central Chile. Two Peruvian species are inferred to be allopolyploids; hybridization between annual lineages derived from independent long‐distance dispersal events from North America gave rise to C. profunda, and hybridization between South American annual and perennial species gave rise to C. cerroana. The relative importance these events are discussed with reference to the observed morphological, ecological, and distributional patterns.
Studies on polynuclear furoquinones. Part 1: Synthesis of tri- and tetra-cyclic furoquinones simulating BCD/ABCD ring system of furoquinone diterpenoids
Authors: Shaik Faruk Hasan , Kar Gandhi Kumar
Published: September 2009

Synthesis of phenanthro[1,2-b]furan-10,11-dione, the core nucleus present in Tanshinone-I is described in 8–10 steps starting from 2-bromo-3,4-dihydro-1-naphthaldehyde. The bromoaldehyde was converted to methyl 2-(2-bromo-1-naphthyl)acetate or 2-(2-bromo-1-naphthyl)acetonitrile following the protocol of functional group transformations. Subsequent Suzuki coupling of this ester/nitrile derivative with furan-2-boronic acid produced [2-(2-furyl)-1-naphthyl]acetic ester/nitrile which on hydrolysis furnished the corresponding acid derivative. Cyclization of the acid followed by oxidation of the phenol, with Fremy’s salt, produced the tetra-cyclic furoquinone, phenanthro[1,2-b]furan-10,11-dione. This method has also been extended for the synthesis of the tricyclic furoquinone, naphtho[1,2-b]furan-4,5-dione.
Increasing Development Impact: Channeling Corporate Social Responsibility Funds Through Public-Private Partnerships
Authors: Soplop Julia , Wetterberg Anna , Indriartoto Ignatius , De León Pellecer María , Goicolea Tere , Roman-Lacayo Manuel
Published: September 2009

In recent years, private fund flows to low-income countries have expanded dramatically. Some of this increase can be attributed to firms' bolstering their corporate social responsibility (CSR) activities by engaging with social concerns in countries where they operate. Public-private partnerships (PPPs), which are collaborations between state and nonstate actors to achieve mutually defined goals, offer one way to steer CSR funds toward development priorities. This paper addresses the question of whether collaboration with public partners can improve the targeting of private funds for social ends, thereby increasing the development impact of CSR activities. We suggest that, when compared with independent corporate initiatives, CSR funds can come closer to meeting development goals through collaborations with public partners and can further improve outcomes if project beneficiaries are directly involved. By drawing on RTI International’s experience with PPPs that incorporate CSR activities, and linking it to the emerging literature on such collaborations, we propose strategies for ensuring a balance between partner priorities, avoiding frustrations with divergent organizational cultures, and incorporating beneficiary participation that can improve alignment of CSR activities with development priorities and thereby increase their impact.
THE OVERHEATING OF FIVE EU NEW MEMBER STATES AND CYCLICALITY OF SYSTEMIC RISK IN THE BANKING SECTOR
Authors: Festić Mejra , Repina Sebastijan , Kavkler Alenka
Published: September 2009

Rapid credit growth has been one of the most pervasive developments in recent years in Central and Eastern Europe. We tested for the significance of macroeconomic and banking sector variables that condition non‐performing loan ratios and the hypothesis of procyclicality between economic activity and improving banking‐sector results in the Baltic States, Bulgaria and Romania. The theory of procyclicality between economic activity and the non‐performing loan ratio was proven. The increased economic activity improved the loan portfolio quality of the banking sector, as indicated by a lower NPL ratio. Due to a high share of loans denominated in a foreign currency and the fact of productivity gains in the tradable sector, the appreciation of the real exchange rate contributed to an improvement in loan portfolio quality. The procyclicality of banking sector performance and high economic activities growth could be a signal of an economy overheating and therefore a slowdown in economic activity is likely to accelerate the growth of the non‐performing loan ratio in the Baltic States, Bulgaria and Romania.