bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential Susceptibility to Excitotoxic Stress in YAC128 Mouse Models of Huntington Disease between Initiation and Progression of Disease
Authors: Graham Rona K. , Pouladi Mahmoud A. , Joshi Prasad , Lu Ge , Deng Yu , Wu Nan-Ping , Figueroa Bryan E. , Metzler Martina , André Véronique M. , Slow Elizabeth J. , Raymond Lynn , Friedlander Robert , Levine Michael S. , Leavitt Blair R. , Hayden Michael R.
Published: February 2009

Huntington disease (HD) is a neurodegenerative disorder caused by an expanded CAG tract in the HD gene. Polyglutamine expansion of huntingtin (htt) results in early, progressive loss of medium spiny striatal neurons, as well as cortical neurons that project to the striatum. Excitotoxicity has been postulated to play a key role in the selective vulnerability of striatal neurons in HD. Early excitotoxic neuropathological changes observed in human HD brain include increased quinolinate (QUIN) concurrent with proliferative changes such as increased spine density and dendritic length. In later stages of the disease, degenerative-type changes are apparent, such as loss of dendritic arborization, a reduction in spine density and reduced levels of 3-hydroxykynurenine and QUIN. It is currently unknown whether sensitivity to excitotoxic stress varies between initiation and progression of disease. Here, we have assessed the excitotoxic phenotype in the YAC128 mouse model of HD by examining the response to excitotoxic stress at different stages of disease. Our results demonstrate that YAC128 mice display enhanced sensitivity to NMDAex vivoand QUINin vivobefore obvious phenotypic changes. In contrast, 10-month-old symptomatic YAC128 mice are resistant to QUIN-induced neurotoxicity. These findings are paralleled by a significant increase in NMDAR-mediated membrane currents in presymptomatic YAC128 dissociated medium spiny neurons progressing to reduced NMDAR-mediated membrane currents with disease progression. These data highlight the dynamic nature of the mutant htt-mediated excitotoxic phenotype and suggests that therapeutic approaches to HD may need to be altered, depending on the stage and development of the disease.
A Refusal and Traversal: Robert Cunninghame Graham's Engagement with Orientalism in Mogreb-el-Acksa
Authors: Long Andrew C.
Published: February 2009

In his fin-de-siècle Morocco travelogue Mogreb-el-Acksa, Robert Cunninghame Graham refused and traversed Orientalist literary discourse. This essay explains how remarkable this refusal and traversal was, given Cunninghame Graham's print culture context and the pressures and pleasures of Orientalist discourse. Most important, the essay distinguishes Cunninghame Graham from his literary peers, especially his friend Joseph Conrad.
Pathways to Druidry: A Case Study of Ár nDraíocht Féin
Authors: Cooper Michael T.
Published: February 2009

Contemporary Druidry is a religious expression that claims ties to the ancient Druids of Indo-European origin. These ties are not necessarily historical as much as they are ideological. As one expression of this form of Druidry, Ár nDraíocht Féin (ADF) represents a vital and growing new religious movement in the United States and Western Europe. The question arises as to how people encounter ADF and what leads them to become adherents. This article analyzes field data to build a framework for understanding the various pathways to ADF. Utilizing the Lofland-Stark model of conversion, the article discusses conversion theory in light of the testimonies of adherents to ADF. The article concludes by suggesting that religious deprivation, religious identity, and religious legitimacy are factors that contribute to conversion and should be a focus of study in conversion theory.
IGF1-induced AKT phosphorylation and cell proliferation are suppressed with the increase in PTEN during luteinization in human granulosa cells
Authors: Goto Maki , Iwase Akira , Harata Toko , Takigawa Sachiko , Suzuki Kyosuke , Manabe Shuichi , Kikkawa Fumitaka
Published: February 2009

Granulosa cells proliferate and then undergo differentiation; an inverse relationship between these processes is observed during terminal follicular growth. During terminal follicular growth and initial luteinization, there is a necessary transition of granulosa cells to a less proliferative and highly steroidogenic form in response to LH. Although the expression of several molecules has been reported to be up-regulated by LH, proliferation/differentiation transition is not fully understood. Here, we show that the expression of a tumor suppressor, phosphatase and tensin homologue deleted on chromosome 10 (PTEN) was induced with human chorionic gonadotropin (hCG) treatment in human luteinized granulosa cells. Pretreatment with hCG attenuated insulin-like growth factor (IGF)-1-induced phosphorylation of AKT and cell proliferation, not phosphorylation of ERK1/2. Moreover, suppression of hCG-induced PTEN expression with siRNA increased AKT phosphorylation and cell proliferation in response to IGF1. We also demonstrate that a PI3K inhibitor, LY294002, not a MEK inhibitor, PD98059, inhibited IGF1-induced cell proliferation. In conclusion, PTEN induced to express by hCG in luteinized granulosa cells that inactivates AKT, not ERK, and attenuates IGF1-induced cell proliferation. PTEN expression may be a trigger for proliferation/differentiation transition in human granulosa cells.
Evaluation of moving‐line contrast degradation without motion
Authors: Becker Michael E.
Published: February 2009

Abstract— A method for evaluation of the contrast of moving step‐grating patterns under smooth‐pursuit eye‐tracking conditions without imaging data acquisition and image analysis is introduced. Periodic optical responses of the display to a set of simple driving signals have been recorded at a fixed location, and the luminance vs. time data has been evaluated to obtain two types of contrast for characterization of the dynamical performance of the display under test: the frame‐convoluted contrast and the frame‐integrated contrast. The relation of this characterization with respect to modulation transfer functions from impulse responses and to the dynamic modulation transfer function from sine‐gratings is explained and discussed. The approach described here provides a detailed and comprehensive characterization of the dynamical properties of electronic displays including both extreme cases of step‐response and impulse‐response with quantities that are related to visual perception. With this type of evaluation, the visual resolution of displays can be described by the same characteristics in the static and the dynamic case. The method is attractive due to limited instrumental efforts and the transparent method of evaluation.
Nonviable seed set enhances plant fitness: the sacrificial sibling hypothesis
Authors: Ghazoul Jaboury , Satake Akiko
Published: February 2009

Many tree species produce far more fruits than eventually mature, with a large proportion of developing fruits being aborted midway through the development process. Whether this is a maternally controlled late‐acting self‐incompatibility mechanism, or an expression of inbreeding depression, is difficult to determine. In either case, however, selection is expected to favor early abortion of inbred or incompatible zygotes to minimize loss of resources. In many species, this does not occur, suggesting the possibility of adaptive reasons for retaining selfed or inbred seeds that are aborted at relatively late developmental stages. We propose that such seeds serve an important function in diluting the impact of pre‐dispersal seed predators by acting as seed predator sinks and thereby increasing the survival probabilities of outcrossed and fully viable seeds. We suggest that selfed seeds retained and developed through the periods of seed predator attack are effectively offered and sacrificed for the benefit of outcrossed seeds.
Cryptic seedling herbivory by nocturnal introduced generalists impacts survival, performance of native and exotic plants
Authors: Strauss Sharon Y. , Stanton Maureen L. , Emery Nancy C. , Bradley Carrie A. , Carleton Alexandra , Dittrich-Reed Dylan R. , Ervin Olivia A. , Gray Levi N. , Hamilton Andrew M. , Rogge Jennifer Harrington , Harper Skye D. , Law Kimberley Cook , Pham Vinh Q. , Putnam Matthew E. , Roth Tara M. , Theil Jacob H. , Wells Lara M. , Yoshizuka Eric M.
Published: February 2009

Although much of the theory on the success of invasive species has been geared at escape from specialist enemies, the impact of introduced generalist invertebrate herbivores on both native and introduced plant species has been underappreciated. The role of nocturnal invertebrate herbivores in structuring plant communities has been examined extensively in Europe, but less so in North America. Many nocturnal generalists (slugs, snails, and earwigs) have been introduced to North America, and 96% of herbivores found during a night census at our California Central Valley site were introduced generalists. We explored the role of these herbivores in the distribution, survivorship, and growth of 12 native and introduced plant species from six families. We predicted that introduced species sharing an evolutionary history with these generalists might be less vulnerable than native plant species.

We quantified plant and herbivore abundances within our heterogeneous site and also established herbivore removal experiments in 160 plots spanning the gamut of microhabitats. As 18 collaborators, we checked 2000 seedling sites every day for three weeks to assess nocturnal seedling predation. Laboratory feeding trials allowed us to quantify the palatability of plant species to the two dominant nocturnal herbivores at the site (slugs and earwigs) and allowed us to account for herbivore microhabitat preferences when analyzing attack rates on seedlings.

The relationship between local slug abundance and percent cover of five common plant taxa at the field site was significantly negatively associated with the mean palatability of these taxa to slugs in laboratory trials. Moreover, seedling mortality of 12 species in open‐field plots was positively correlated with mean palatability of these taxa to both slugs and earwigs in laboratory trials.

Counter to expectations, seedlings of native species were neither more vulnerable nor more palatable to nocturnal generalists than those of introduced species. Growth comparison of plants within and outside herbivore exclosures also revealed no differences between native and introduced plant species, despite large impacts of herbivores on growth.

Cryptic nocturnal predation on seedlings was common and had large effects on plant establishment at our site. Without intensive monitoring, such predation could easily be misconstrued as poor seedling emergence.
Fluctuating patch boundaries in a native annual forb: the roles of niche and dispersal limitation
Authors: Moore Kara A.
Published: February 2009

Abiotic, biotic, and dispersal constraints jointly control the spatial distributions of species, but few studies have directly evaluated how these forces interact and vary over time to create dynamic spatial distributions. Through three years of observation and two years of field manipulation, I investigated simultaneous constraints on the spatial distribution ofLupinus nanus, a native annual legume that grows in dense patches in California grasslands. I transplantedL. nanusacross its own patch boundaries, yet within apparently suitable habitat, and assessed the demographic success of naturally occurring and seeded plants in plots with and without competitor removal in years that varied in temperature and rainfall. Core sites were defined as those consistently densely occupied, whereas peripheral sites were densely occupied only during some years, and exterior sites were consistently unoccupied or very sparsely occupied. Site types (core, periphery, and exterior) differed in soil moisture, P, and NO3. Competition limited emergence in all site types in the dry/warm year and in patch peripheries in the wet/cool year. Population fitness (seeds produced per seed added) was >1.0 in cores during all years. Peripheral sites had fitness near replacement in the wet/cool year, which was greatly increased by competition removal. Exterior fitness was <1.0 in both experimental years, regardless of seed addition and competitor removal. Seed addition did not increase site‐specific fitness, and a seed bank was found to be present in all site types. Herbivory was greater in patch cores and peripheries than in exteriors. Soil variation exerted the most consistent control over patch limits, while competition played an intermittent role in excludingLupinusfrom patch peripheries. The dynamic distribution ofL. nanusis the product of temporal variation in specific abiotic and biotic niche axes, primarily soil characteristics and competition, rather than dispersal limitation.
Methods to quantify variable importance: implications for the analysis of noisy ecological data
Authors: Murray Kim , Conner Mary M.
Published: February 2009

Determining the importance of independent variables is of practical relevance to ecologists and managers concerned with allocating limited resources to the management of natural systems. Although techniques that identify explanatory variables having the largest influence on the response variable are needed to design management actions effectively, the use of various indices to evaluate variable importance is poorly understood. Using Monte Carlo simulations, we compared six different indices commonly used to evaluate variable importance; zero‐order correlations, partial correlations, semipartial correlations, standardized regression coefficients, Akaike weights, and independent effects. We simulated four scenarios to evaluate the indices under progressively more complex circumstances that included correlation between explanatory variables, as well as a spurious variable that was correlated with other explanatory variables, but not with the dependent variable. No index performed perfectly under all circumstances, but partial correlations and Akaike weights performed poorly in all cases. Zero‐order correlations was the only measure that detected the presence of a spurious variable, whereas only independent effects assigned overlap areas correctly once the spurious variable was removed. We therefore recommend using zero‐order correlations to eliminate predictor variables with correlations near zero, followed by the use of independent effects to assign overlap areas and rank variable importance.
Mycorrhizal densities decline in association with nonnative plants and contribute to plant invasion
Authors: Vogelsang Keith M. , Bever James D.
Published: February 2009

Belowground interactions between herbaceous native species and nonnative species is a poorly understood but emerging area of interest to invasive‐species researchers. Positive feedback dynamics are commonly observed in many invaded systems and have been suspected in California grasslands, where native plants associate strongly with soil mutualists such as arbuscular mycorrhizal fungi. In response to disturbance, invading nonnative plants proliferate, and to the degree these species associate weakly with soil mutualists, we would expect mutualist efficacy to degrade over time. Degraded mutualist efficacy would negatively impact mutualist‐dependent native species or their recruitment following a disturbance. We investigated the feedback dynamics of soil conditioned both with native and nonnative herbaceous communities of southern California grasslands to test this degraded mutualist hypothesis. Using a mesocosm approach, we inoculated each community with live soil originating from a remnant native grassland and varied the plant communities (i.e., native or nonnative) along a plant–species‐richness gradient. After one year, we then used this conditioned soil for reciprocal feedback tests on a native and nonnative indicator species. We show that a native herbaceous forb (Gnaphalium californicum) grows best in soil conditioned by a diverse mix of other native species that includes G. californicum but is inhibited by soil conditioned by a diverse mix of nonnative species. We also show that an invasive, nonnative herbaceous forb (Carduus pycnocephalus) exhibits strong growth in soil lacking arbuscular mycorrhizal fungi and in soil conditioned by a diverse mix of nonnative species that include C. pycnocephalus, and that it is inhibited by the same soil that best promotes the native, G. californicum. Separate bioassays for mycorrhizal density show a reduction of arbuscular mycorrhizal fungi in the nonnative‐conditioned soil relative to the native‐conditioned soil, which suggests that nonnative species do not promote the growth of mycorrhizal fungi in the same way that native species do. The growth patterns resulting from the vegetative history of these distinct soil communities provide evidence of a biotic feedback mechanism that may account for the maintenance of persistent communities of nonnative (and often invasive) plants ubiquitous throughout California grasslands.
Warming strengthens an herbivore–plant interaction
Authors: O'Connor Mary I.
Published: February 2009

Temperature has strong, predictable effects on metabolism. Through this mechanism, environmental temperature affects individuals and populations of poikilotherms by determining rates of resource use, growth, reproduction, and mortality. Predictable variation in metabolic processes such as growth and reproduction could affect the strength of species interactions, but the community‐level consequences of metabolic temperature dependence are virtually unexplored. I experimentally tested the hypothesis that plant–herbivore interaction strength increases with temperature using a common species of marine macroalga (Sargassum filipendula) and the grazing amphipodAmpithoe longimana. Increasing temperature increased per capita interaction strength in two independent experiments and reversed a positive effect of temperature on plant growth. Temperature did not alter palatability of plant tissue to herbivores or average herbivore feeding rate. A predictable effect of temperature on herbivore–plant interaction strength could provide key information toward understanding local food web responses to changing temperatures at different spatial and temporal scales. Efforts to extend the effects of physiological mechanisms to larger scale patterns, including projections of the ecological effects of climate change, must be expanded to include the effects of changing conditions on trophic interactions.
Indirect effects of invasive predators on litter decomposition and nutrient resorption on seabird‐dominated islands
Authors: Wardle David A. , Bellingham Peter J. , Bonner Karen I. , Mulder Christa P. H.
Published: February 2009

Despite recent interest in the ecosystem impacts of invasive aboveground organisms, most work in this area has focused on effects of invasive plants, and the effects of invasive herbivores and predators remain poorly understood. We studied 18 forested, offshore islands in northern New Zealand. Nine of these host high densities of burrowing seabirds that serve as ecosystem drivers by transporting nutrients from the ocean to land. The other nine have been invaded over the past 50–150 years by rat species introduced from Europe which serve as predators of seabird eggs and chicks and severely reduce their densities. We collected fully expanded leaves and fresh leaf litter from invaded and uninvaded islands for each of 12 perennial plant species that represent a wide spectrum of life forms from ground dwelling to emergent canopy species. We found that, across these species, invasion by rats significantly reduced nitrogen (N) but not phosphorus (P) concentrations of foliage and litter, promoted N but not P resorption from leaves before litter fall, and reduced the release of N but not P from decomposing litter. Rat invasion also negatively affected litter decomposability but had no overall effects on litter quality variables other than N. Our results provide evidence that rat invasion causes more conservative cycling of N but not P through foliage and litter and limitation of ecological processes by N but not P. We found few instances in which the effects of rat invasion on response variables varied significantly across plant species, meaning that invasion had similar effects for species that varied greatly in growth form and foliar and litter quality. Further, correlation analyses across the 12 species showed that foliar and litter quality traits were poor predictors of how invasion effects on resorption and decomposition variables varied among species. Our results show that the effects of invasive predators on native prey can have substantial indirect effects on variables relevant for ecosystem functioning. These types of effects are probably widespread, especially given the role of seabirds in improving soil fertility in many coastal ecosystems worldwide and the wide global distribution of predators of seabirds.
Testing the functional significance of microbial community composition
Authors: Strickland Michael S. , Lauber Christian , Fierer Noah , Bradford Mark A.
Published: February 2009

A critical assumption underlying terrestrial ecosystem models is that soil microbial communities, when placed in a common environment, will function in an identical manner regardless of the composition of that community. Given high species diversity in microbial communities and the ability of microbes to adapt rapidly to new conditions, this assumption of functional redundancy seems plausible. We test the assumption by comparing litter decomposition rates in experimental microcosms inoculated with distinct microbial communities. We find that rates of carbon dioxide production from litter decomposition were dependent upon the microbial inoculum, with differences in the microbial community alone accounting for substantial (∼20%) variation in total carbon mineralized. Communities that shared a common history with a given foliar litter exhibited higher decomposition rates when compared to communities foreign to that habitat. Our results suggest that the implicit assumption in ecosystem models (i.e., microbial communities in the same environment are functionally equivalent) is incorrect. To predict accurately how biogeochemical processes will respond to global change may require consideration of the community composition and/or adaptation of microbial communities to past resource environments.
A single phosphorus treatment doubles growth of cyanobacterial lichen transplants
Authors: McCune Bruce , Caldwell Bruce A.
Published: February 2009

Lichens are reputedly slow growing and become unhealthy or die in response to supplements of the usual limiting resources, such as water and nitrogen. We found, however, that the tripartite cyanobacterial lichen Lobaria pulmonaria doubled in annual biomass growth after a single 20‐minute immersion in a phosphorus solution (K2HPO4), as compared to controls receiving no supplemental phosphorus. This stimulation of cyanolichens by phosphorus has direct relevance to community and population ecology of lichens, including improving models of lichen performance in relation to air quality, improving forest management practices affecting old‐growth associated cyanolichens, and understanding the distribution and abundance of cyanolichens on the landscape. Phosphorus may be as important a stimulant to cyanobacterial‐rich lichen communities as it is to cyanobacteria in aquatic ecosystems.
Mitigation of egg limitation in parasitoids: immediate hormonal response and enhanced oogenesis after host use
Authors: Casas Jérôme , Vannier Fabrice , Mandon Nicole , Delbecque Jean Paul , Giron David , Monge Jean Paul
Published: February 2009

Synovigenic insects (i.e., insects emerging with few ripe eggs and maturing more eggs during the course of their lifetime) may suffer from transient egg limitation due to the stochastic nature of encounters with patchy hosts and the low availability of ripe eggs at any given time point. Egg limitation also affects the stability of host–parasitoid models. Thus, quantification of the behavioral decisions influencing egg maturation, identification of the underlying physiological mechanisms, and determination of the rate of egg maturation are highly relevant to both parasitoid behavioral ecology and host–parasitoid population dynamics. The aim of this study was to identify, in a highly controlled setting, the physiological processes responsible for egg manufacture after varying host use by a synovigenic parasitoid. We quantified the time course of the reproductive hormonal response and subsequent egg production in the host feeding bruchid parasitoid, Eupelmus vuilleti (Hymenoptera: Eupelmidae) for three treatments: (1) host examination without further host use, (2) host feeding, and (3) host feeding followed by oviposition. We carried out continuous behavioral observations with single hosts, enzyme immunoassays for quantifying ecdysteroids, and ovary dissection. Ecdysone levels increased within two minutes of contact with a host, the fastest hormonal response reported for any insect. Even simple contact with a host, without further host use, triggered an increase in hormone levels, leading to the maturation of a single egg, using body reserves only. Feeding on the host caused a much larger increase in ecdysone levels and was followed by a marked increase in oogenesis. Oviposition had a weak effect on hormone levels, but increased oogenesis. We discuss the mechanisms responsible for these rapid responses, the source of ecdysteroids, and the implications of our results for the population dynamics of host–parasitoid systems and the behavioral ecology of synovigenic species.
Barnacle, fucoid, and mussel recruitment in the Gulf of Maine, USA, from 1997 to 2007
Authors: Petraitis Peter S. , Liu Harrison , Rhile Erika C.
Published: February 2009

Experimental clearings in macroalgal (Ascophyllum nodosum) stands were made at 12 sites in 1996 to determine if mussel beds and macroalgal stands on sheltered intertidal shores of New England represent alternative community states. Sites were located on Swan's Island, Maine, USA. At each site an uncleared control plot and four sizes of circular clearings, which mimicked ice scour events, were established. The purpose of this data set is to provide access to recruitment data collected in the experimental plots from 1997 to 2007.
Time asymmetry in the palaeobiogeographic history of species
Authors: Lopez-Martinez Nieves
Published: February 2009

The difficulties and hindrances of palaeobiogeography and historical biogeography in its long, sterile search for centres of origin or ancestral areas of species, leading some authors to withdraw the centre-of-origin as a non-scientific concept, are here considered as signals and not artefacts for the recognition of patterns in the biogeographic history of lineages. The time-symmetric model, which assumes gradual origination and extinction processes of a species, is here questioned and an alternative time-asymmetric model is proposed. The origination and expansion processes of a species history would be much faster and more unpredictable than the often gradual, long, predictable extinction process marked by previous signals of geographic area contraction. Monitored biological invasions, plankton blooms and episodes of coordinated migrations illustrate the fast expansion of novel species behaving as dissipative structures. The asymmetric biogeographic model is tested through palaeobiogeographic data on Old World mammal species and by the consistent preference of biostratigraphers for species appearance against species extinction as time-marker bioevents. Time-asymmetry is a common phenomenon of nature, indicating that asymmetry could well be a general property of Time itself.
Experimental Study on the Performance of a Hybrid Water Heater
Authors: Dong Lihua , Suzuki Yuko , Kobayashi Noriyuki
Published: February 2009

We study a hybrid adsorption heat pump water heater for domestic use that comprises a water heater with dual heat sources. This water heater combines the advantages of an adsorption heat pump and a conventional gas boiler. An experimental study on the output and coefficient of performance (COP) of the system was performed under various environmental conditions, and some important conclusions and suggestions that improved the hybrid water heater system are presented. In addition, a numerical analysis for experimental results was presented by process simulation, and then the COP of the system was examined.
And a Little Child Shall Lead Them--Economic Recovery in 3 Easy Steps
Authors: Barnett William S
Published: February 2009

Here is a recovery plan sure to work and as easy as child's play from W. Steven Barnett, the Board of Governors Professor of Education at Rutgers.
Political change in Serbia in the perspective of social learning: An idea revisited
Authors: Spasic Ivana
Published: February 2009

The paper contains a retrospective of the thesis that 'social learning' may be deployed as analytical framework to understand political change in Serbia, first proposed in 2001. The thesis contends that the events immediately before and after the toppling of Milosevic's regime in 2000 may be interpreted as outcomes of a process of collective learning by Serbian citizens. On the basis of the findings of three-wave qualitative study 'Politics and Everyday Life', as well as other research, the paper seeks to answer the question whether the idea of 'social learning' stands or falls when confronted with the developments taking place in Serbian political life between 2001 and 2008.
The idea of European citizen after the 'period of reflection' and the Treaty of Lisbon
Authors: Stupar Milorad
Published: February 2009

The author analyzes the Reform Treaty and comes to the conclusion that there are changes in the concept of European citizen in it, in the sense that its democratic potential has been enhanced. In showing this the author relies on 'pragmatic model' for understanding individual and collective identity as it was introduced in social science by sociologist Raymond Breton.
'Nista drugo do jedna slika' - Stajn Rokanova teorija o razvoju drzava u Evropi
Authors: Ristic Irena
Published: February 2009

(nemacki) Der norwegische Soziologe Stein Rokkan, der sich mit state/nation building sowie mit dem Demokratisierungsprozess in Europa besch?ftigte, hinterlie? eine beachtliche Menge an Arbeiten, in denen er versuchte ein eigenes Makromodell der politischen Entwicklung Europas zu entwerfen. Sein Ziel war, anhand verschiedener historischer Prozesse, die die Entstehung von Staaten und Nationen sowie deren Demokratisierung beinflussten, die Vielseitigkeit der europ?ischen Staaten zu erkl?ren. Rokkan w?hlte dabei einen antideterministisch und breiten Zugang, wodurch sich seine Theorie im wesentlichen von den meisten anderen state/nation building Theorien unterscheidet. Aus diesem Grund scheint Rokkans Theorie vor allem f?r die historisch vergleichende Makrosoziologie, sowie f?r die Analyse langfristiger Entwicklungswege geeignet. Dieser Artikel besch?ftigt sich im ersten Teil mit Rokkans Auffassungen einer Theoriebildung an sich. Im zweiten Teil werden seine Theorie, ihre Variablen und Dimensionen dargestellt.
From family planning to population policy: A paradigm shift in Serbian demography at the end of the 20th century
Authors: Drezgic Rada
Published: February 2009

This paper traces changes in the dominant paradigm of Serbian demography that took palace in the context of major socio-political changes during the late twentieth century. The changes are traced both in the realm of research and social policy. It is argued that demographic transition theory remained the main explanatory model but that its modified version which gives precedence to ideational vs. structural variables gained the dominant status. In the realm of social policy the ideology of family planning was replaced by population policy ideology. It is further argued that alarming discourses and sharp rhetoric about population problems did not result in formulation of a system of specific measures of population policy. Thus, the author claims, demographic discourses that at the time saturated public spaces were constitutive for - gender and national -identity politics and not inconsequential for social policy.
Identity and interculturality: Serbia as a place of interweaving of Balkans and (Central) Europe
Authors: Djuric Jelena
Published: February 2009

This article is an attempt to find a suitable concept for possible reconstruction and integration of various cultural identities, which are diverse and internally layered. The view on issues of identity taken from Serbia - the country in 'transition' faring through different temptations in search for an appropriate identity which could mean a chance for integrity in processes of identity changes - is specific in as much as it could consider itself as a subject of history and not only as 'otherness' designated by other parties.
Religious Europe, Russia and Serbia: Past and present arguments of empirical evidence: The case of Serbia
Authors: Blagojevic Mirko
Published: February 2009

The text is the last contribution to the title subject and a sequel to the two previous texts by the same author already published in this magazine. The text discusses the evolution of religious situation in Serbia, predominantly Orthodox one, in the last century and the first decade of the twenty-first century. A religious situation in such a long period of time is always discussed within the context of the entire Serbian society and lately by comparison with (non)religious Europe and Russia.
Heidegger's concept of 'Being-There' and fundamental concepts of traditional ontology
Authors: Molnar-Sivc Milotka
Published: February 2009

Although the question of relationship between basic concepts of traditional ontology and central concepts of fundamental ontology is not a topic which is systematically dealt with in Being and Time, it is obvious that some of the theses which are crucial not only for Heidegger's interpretation of philosophical tradition, but also for the whole project of fundamental ontology, concern this 'conceptual scheme'. In fact, the backbone of Heidegger's critical confrontation with dominant philosophical conceptions is the question of relationship between the concept of 'substance' and the concept of 'Being', i.e. the discussion of philosophical doctrines in which 'Being' is reduced to 'substance'. Besides this context, which concerns the ontological problematics in the strict sense, it is possible to show that the refutation of the basic categories of traditional ontology is an issue which has a decisive role in more concrete phases of the realization of the project of fundamental ontology. This is especially confirmed in Heidegger's discussion of the concept of 'Being-There'. The interpretation of Heidegger's treatment of the relationship between the concepts of 'Being-there', 'existence' and 'existentials' on the one hand, and the concepts of 'substance', 'essence' and 'categories' on the other, shows that one of Heidegger's basic theses is that a transformation of concepts of traditional ontology is necessary for an appropriate understanding of human being.
The birth of Russian intelligentsia from the spirit of enlightenment: Alexander Radishchev (I)
Authors: Subotic Milan
Published: February 2009

This text is the first part of a larger study about Alexander Radishchev, one of the leading representatives of Enlightenment in Russia's XVIII Century. Analyzing Voltaire's and Diderot's relationship with Catherine II, the Empress of Russia, in the Introduction of this article, the author formulates the reasons for thematization of Russian reception of Enlightenment. Since Radishchev is considered as 'the father of Russian intelligentsia', different approaches to the meaning of the concept of 'Russian intelligentsia' are considered in the first chapter. Radishchev's biography is interpreted in the second chapter in order to facilitate the understanding of his ideas. Interpretation of his ideas, as well as of Catherina's 'enlightened absolutism', will be subject to further consideration in the second part of the study.
Discrete particle swarm optimization algorithm for solving optimal sensor deployment problem
Authors: Rapaic Milan , Kanovic Zeljko , Jelicic Zoran
Published: February 2009

This paper addresses the Optimal Sensor Deployment Problem (OSDP). The goal is to maximize the probability of target detection, with simultaneous cost minimization. The problem is solved by the Discrete PSO (DPSO) algorithm, a novel modification of the PSO algorithm, originally presented in the current paper. DPSO is general-purpose optimizer well suited for conducting search within a discrete search space. Its applicability is not limited to OSDP, it can be used to solve any combinatorial and integer programming problem. The effectiveness of the DPSO in solving OSDP was demonstrated on several examples.
Synthesis of adaptive impedance control for bipedal robot mechanisms
Authors: Petrovic Milena , Rodic Aleksandar
Published: February 2009

The paper describes the impedance algorithm in locomotion of humanoid robot with proposed parameter modulation depending on the gate phase. The analysis shows influence of walking speed and foot elevation on regulator's parameters. Chosen criterion cares for footpath tracking and needed energy for that way of walking. The experiments give recommendation for impedance regulator tuning.
Analysis of speech waveform quantization methods
Authors: Tadic Predrag , Djurovic Zeljko , Kovacevic Branko
Published: February 2009

Digitalization, consisting of sampling and quantization, is the first step in any digital signal processing algorithm. In most cases, the quantization is uniform. However, having knowledge of certain stochastic attributes of the signal (namely, the probability density function, or pdf), quantization can be made more efficient, in the sense of achieving a greater signal to quantization noise ratio. This means that narrower channel bandwidths are required for transmitting a signal of the same quality. Alternatively, if signal storage is of interest, rather than transmission, considerable savings in memory space can be made. This paper presents several available methods for speech signal pdf estimation, and quantizer optimization in the sense of minimizing the quantization error power.
Electronic stimulators for surface neural prosthesis
Authors: Broderick Barry , Breen Paul , Ólaighin Gearóid
Published: February 2009

This paper presents the technological advancements in neural prosthesis devices using Functional Electrical Stimulation (FES). FES refers to the restoration of motor functions lost due to spinal cord injury (SCI), stroke, head injury, or diseases such as Cerebral Palsy or Multiple Sclerosis by eliciting muscular contractions through the use of a neuromuscular electrical stimulator device. The field has developed considerably since its inception, with the miniaturisation of circuity, the development of programmable and adaptable stimulators and the enhancement of sensors used to trigger the application of stimulation to suit a variety of FES applications. This paper discusses general FES system design requirements in the context of existing commercial and research FES devices, focusing on surface stimulators for the upper and lower limbs. These devices have demonstrated feasible standing and stepping in a clinical setting with paraplegic patients, improvements in dropped foot syndrome with hemiplegic patients and aided in the restoration of grasping function in patients with upper limb motor dysfunction.
Surface electrical stimulation for foot drop: Control aspects and walking performance
Authors: Stein Richard , Rolf Robert , Everaert Dirk , Bobet Jacques , Chong Suling
Published: February 2009

Use of electrical stimulation to correct foot drop in hemiplegia was proposed over 40 years ago. Recently, improved control strategies have been developed and implemented in commercially available devices. In this article we review the control methods that have been used and present some results from a multi-center clinical trial. A foot-drop stimulator improves the gait pattern and results in an immediate increase in walking speed. In this sense it acts like an ankle-foot orthosis and this immediate increase will be referred to as an orthotic effect. Prolonged use of a foot drop stimulator over a period of months results in further, large increases in walking speed both with the stimulator on and off. Evidence indicates that a part of this increase results from daily use that strengthens residual cortico-spinal connections. Therefore the improvement over time will be referred to as a therapeutic effect. We found that people with non-progressive and progressive conditions of the central nervous system have an orthotic benefit, as well as a therapeutic up to 3 months of use. In generally non-progressive conditions such as stroke, further therapeutic increases are seen up to at least 11 months of use. In disorders such as multiple sclerosis, the progression of the disease eventually overcomes the early therapeutic effects. In conclusion, many individuals can benefit from commercially available foot-drop stimulators with improved control strategies and cosmetic design.
Neural prostheses for walking restoration
Authors: Popovic Dejan , Popovic Mirjana , Dosen Strahinja
Published: February 2009

We review the state of the art of multi-channel electrical stimulation (ES) systems with surface electrodes for assistance in the standing and walking of paraplegics and hemiplegics. For the group of complete paraplegics, walking achieved with available ES systems is below their expectations, especially since these systems cannot compete with mobility provided to them by a wheelchair. However, standing and walking with ES systems are beneficial because they contribute to the improvement of physiological functions. For individuals who can stand with some arm support (e.g., paraplegics with incomplete injury and hemiplegics), the current ES systems are an effective augmentation of walking. We suggest that an ES system for walking of incomplete paraplegics and hemiplegics will be better accepted if the stimulation is regulated by a rule-based control, that is, a preprogrammed, sensor-triggered activation of several muscles resulting in normal walking. We present a method to obtain muscle activity profiles from simulation of a customized model of the patient that can be used for the synthesis of rules for control.
Fes cycling
Authors: Berkelmans Rik
Published: February 2009

Many research with functional electrical stimulation (FES) has been done to regain mobility and for health benefits. Better results have been reported for FES-cycling than for FES-walking. The majority of the subjects during such research are people with a spinal cord injury (SCI), cause they often lost skin sensation. Besides using surface stimulation also implanted stimulators can be used. This solves the skin sensation problem, but needs a surgery. Many physiological effects of FES-cycling has been reported, e.g., increase of muscles, better blood flow, reduction of pressure ulcers, improved self-image and some reduction of bone mineral density (BMD) loss. Also people with an incomplete SCI benefit by FES-cycling, e.g. cycling time without FES, muscle strength and also the walking abilities increased. Hybrid exercise gives an even better cardiovascular training. Presently 4 companies are involved in FES-cycling. They all have a stationary mobility trainer. Two of them also use an outdoor tricycle. One combined with voluntary arm cranking. By optimizing the stimulation parameters the power output and fatigue resistance will increase, but will still be less compared to voluntary cycling.
Abdominal stimulation for respiratory support in tetraplegia: A tutorial review
Authors: Gollee H. , Hunt K.J. , Fraser M.H. , Mclean A.N.
Published: February 2009

Neuromuscular stimulation of the abdominal wall muscles can provide respiratory support in tetraplegia, where the main expiratory muscles are affected by paralysis. Stimulation may be applied by simple surface stimulation, resulting in a uniform muscle contraction which can help to improve expiratory function for coughing and breathing. In this review, an overview of methods and approaches available for abdominal muscle stimulation is given. Studies are discussed which show that this technique can lead to improvements in expiratory flow and tidal volume, resulting in enhanced cough and breathing functions. Approaches are introduced which aim to integrate abdominal stimulation with the subject's own voluntary breathing functions. These are illustrated with experimental results from the evaluation of automatic stimulation methods in tetraplegic patients. Clinical significance and applications are discussed and future developments are outlined.
Comparison of the antibacterial activity, volatiles and fatty acid composition of lipids of Phycopsis species collected at different locations from the Bay of Bengal (Orissa coast)
Authors: Mishra Pravat , Sree Ayinampudi
Published: February 2009

The fatty acid composition as well as the volatiles and an antibacterial screening of the total lipids isolated from marine sponge Phycopsis sp. collected at two different locations from the Bay of Bengal of the Orissa coast having different morphological features were studied. The content of linear saturated acids was 30.25 % in Phycopsis sp. 1, while their content reached 50.33 % in Phycopsis sp. 2. The amount of monobranched, saturated acids was 44.87 % in Phycopsis sp.1 and 38.83 % in Phycopsis sp. 2. There was more phytanic acid (7.92 %) in Phycopsis sp. 2 than in Phycopsis sp. 1 (4.06 %). The amount of 5,9-pentacosadienoic acid was found to be 5.54 % in Phycopsis sp. 1, while it was absent in Phycopsis sp. 2. Both species showed differences in their fatty acid composition and volatiles as well as in the antibacterial screening of their lipid extracts.
Stability order of isomeric benzenoid hydrocarbons and Kekulé structure count
Authors: Radenkovic Slavko , Gutman Ivan
Published: February 2009

The commonly accepted opinion that the thermodynamic stability of isomeric benzenoid hydrocarbons (assessed by their total ?-electron energy and various resonance energies) increases with increasing number of Kekul? structures is shown to be violated in numerous cases. The smallest examples of such anomalous behavior are two hexacyclic pericondensed benzenoids of formula C24H14 and several pairs of heptacyclic catacondensed benzenoids of formula C30H18.
Hydrogen storage in complex metal hydrides
Authors: Bogdanovic Borislav , Felderhoff Michael , Streukens Guido
Published: February 2009

Complex metal hydrides such as sodium aluminohydride (NaAlH4) and sodium borohydride (NaBH4) are solid-state hydrogen-storage materials with high hydrogen capacities. They can be used in combination with fuel cells as a hydrogen source thus enabling longer operation times compared with classical metal hydrides. The most important point for a wide application of these materials is the reversibility under moderate technical conditions. At present, only NaAlH4 has favorable thermodynamic properties and can be employed as a thermally reversible means of hydrogen storage. By contrast, NaBH4 is a typical non-reversible complex metal hydride; it reacts with water to produce hydrogen.
Mapping the concentration changes during the dynamic processes of crevice corrosion by digital holographic reconstruction
Authors: Jia Henglei , Chen Shenhao , Yuan Boyu , Wang Chao , Li Liang
Published: February 2009

The dynamic process of crevice corrosion during anodic dissolution of a crevice electrode in a 5.0 mmol dm-3 NaCl solution has been studied by digital holographic reconstruction. Digital holographic reconstruction has been proved to be an effective and in situ technique to detect the changes in the solution concentration because useful and direct information can be obtained from the three-dimensional images. It provides a valuable method for a better understanding of the mechanism of crevice corrosion by studying the dynamic processes of changes in the solution concentration at the interface of crevice corrosion.