bluuebunny/crossref_metadata_2025 huggingface dataset:
The Virtual Director: a Correlation‐Based Online Viewing of Human Motion
Authors: Assa J. , Wolf L. , Cohen‐Or D.
Published: June 2010

Automatic camera control for scenes depicting human motion is an imperative topic in motion capture base animation, computer games, and other animation based fields. This challenging control problem is complex and combines both geometric constraints, visibility requirements, and aesthetic elements. Therefore, existing optimization‐based approaches for human action overview are often too demanding for online computation.

In this paper, we introduce an effective automatic camera control which is extremely efficient and allows online performance. Rather than optimizing a complex quality measurement, at each time it selects one active camera from a multitude of cameras that render the dynamic scene. The selection is based on the correlation between each view stream and the human motion in the scene. Two factors allow for rapid selection among tens of candidate views in real‐time, even for complex multi‐character scenes: the efficient rendering of the multitude of view streams, and optimized calculations of the correlations using modified CCA. In addition to the method's simplicity and speed, it exhibits good agreement with both cinematic idioms and previous human motion camera control work. Our evaluations show that the method is able to cope with the challenges put forth by severe occlusions, multiple characters and complex scenes.
Printed Patterns for Enhanced Shape Perception of Papercraft Models
Authors: Xue Su , Chen Xuejin , Dorsey Julie , Rushmeier Holly
Published: June 2010

Papercraft models can serve as inexpensive prototypes in shape design applications. However, in making the models some geometric detail is necessarily lost, and artificial creases may be visible, thereby limiting the utility of these models. To compensate for these practical limitations, we introduce the use of printed patterns on papercraft models to enhance the perception of the shape they are intended to represent. We propose pattern generation schemes that modulate the sizes, directions, and densities of glyphs of patterns based on geometric attributes. We present a psychophysical experiment designed to explore the effect that printed patterns have on the perception of the papercraft model shapes. We find that models with printed patterns are perceived to represent the intended shape more accurately, and, further, that the type of printed pattern has an impact on the perceived shape.
Consensus Skeleton for Non‐rigid Space‐time Registration
Authors: Zheng Q. , Sharf A. , Tagliasacchi A. , Chen B. , Zhang H. , Sheffer A. , Cohen‐Or D.
Published: June 2010

We introduce the notion of consensus skeletons for non‐rigid space‐time registration of a deforming shape. Instead of basing the registration on point features, which are local and sensitive to noise, we adopt the curve skeleton of the shape as a global and descriptive feature for the task. Our method uses no template and only assumes that the skeletal structure of the captured shape remains largely consistent over time. Such an assumption is generally weaker than those relying on large overlap of point features between successive frames, allowing for more sparse acquisition across time. Building our registration framework on top of the low‐dimensional skeleton‐time structure avoids heavy processing of dense point or volumetric data, while skeleton consensusization provides robust handling of incompatibilities between per‐frame skeletons. To register point clouds from all frames, we deform them by their skeletons, mirroring the skeleton registration process, to jump‐start a non‐rigid ICP. We present results for non‐rigid space‐time registration under sparse and noisy spatio‐temporal sampling, including cases where data was captured from only a single view.
Electors Voting for Fast Automatic Shape Correspondence
Authors: Kin‐Chung Au Oscar , Tai Chiew‐Lan , Cohen‐Or Daniel , Zheng Youyi , Fu Hongbo
Published: June 2010

This paper challenges the difficult problem of automatic semantic correspondence between two given shapes which are semantically similar but possibly geometrically very different (e.g., a dog and an elephant). We argue that the challenging part is the establishment of a sparse correspondence and show that it can be efficiently solved by considering the underlying skeletons augmented with intrinsic surface information. To avoid potentially costly direct search for the best combinatorial match between two sets of skeletal feature nodes, we introduce a statistical correspondence algorithm based on a novel voting scheme, which we call electors voting. The electors are a rather large set of correspondences which then vote to synthesize the final correspondence. The electors are selected via a combinatorial search with pruning tests designed to quickly filter out a vast majority of bad correspondence. This voting scheme is both efficient and insensitive to parameter and threshold settings. The effectiveness of the method is validated by precision‐recall statistics with respect to manually defined ground truth. We show that high quality correspondences can be instantaneously established for a wide variety of model pairs, which may have different poses, surface details, and only partial semantic correspondence.
A Hybrid Approach to Multiple Fluid Simulation using Volume Fractions
Authors: Kang Nahyup , Park Jinho , Noh Junyong , Shin Sung Yong
Published: June 2010

This paper presents a hybrid approach to multiple fluid simulation that can handle miscible and immiscible fluids, simultaneously. We combine distance functions and volume fractions to capture not only the discontinuous interface between immiscible fluids but also the smooth transition between miscible fluids. Our approach consists of four steps: velocity field computation, volume fraction advection, miscible fluid diffusion, and visualization. By providing a combining scheme between volume fractions and level set functions, we are able to take advantages of both representation schemes of fluids. From the system point of view, our work is the first approach to Eulerian grid‐based multiple fluid simulation including both miscible and immiscible fluids. From the technical point of view, our approach addresses the issues arising from variable density and viscosity together with material diffusion. We show that the effectiveness of our approach to handle multiple miscible and immiscible fluids through experiments.
Two‐Colored Pixels
Authors: Pavić Darko , Kobbelt Leif
Published: June 2010

In this paper we show how to use two‐colored pixels as a generic tool for image processing. We apply two‐colored pixels as a basic operator as well as a supporting data structure for several image processing applications. Traditionally, images are represented by a regular grid of square pixels with one constant color each. In the two‐colored pixel representation, we reduce the image resolution and replace blocks of N × N pixels by one square that is split by a (feature) line into two regions with constant colors. We show how the conversion of standard mono‐colored pixel images into two‐colored pixel images can be computed efficiently by applying a hierarchical algorithm along with a CUDA‐based implementation. Two‐colored pixels overcome some of the limitations that classical pixel representations have, and their feature lines provide minimal geometric information about the underlying image region that can be effectively exploited for a number of applications. We show how to use two‐colored pixels as an interactive brush tool, achieving realtime performance for image abstraction and non‐photorealistic filtering. Additionally, we propose a realtime solution for image retargeting, defined as a linear minimization problem on a regular or even adaptive two‐colored pixel image. The concept of two‐colored pixels can be easily extended to a video volume, and we demonstrate this for the example of video retargeting.
Fast High‐Dimensional Filtering Using the Permutohedral Lattice
Authors: Adams Andrew , Baek Jongmin , Davis Myers Abraham
Published: June 2010

Many useful algorithms for processing images and geometry fall under the general framework of high‐dimensional Gaussian filtering. This family of algorithms includes bilateral filtering and non‐local means. We propose a new way to perform such filters using the permutohedral lattice, which tessellates high‐dimensional space with uniform simplices. Our algorithm is the first implementation of a high‐dimensional Gaussian filter that is both linear in input size and polynomial in dimensionality. Furthermore it is parameter‐free, apart from the filter size, and achieves a consistently high accuracy relative to ground truth (> 45 dB). We use this to demonstrate a number of interactive‐rate applications of filters in as high as eight dimensions.
Opening the Black Box of Upper Echelons: Drivers of Poor Information Processing During the Financial Crisis
Authors: Rost Katja , Osterloh Margit
Published: June 2010

Manuscript Type:Empirical

Research Question/Issue:Why did the majority of directors prior to the financial crisis not have the foresight to predict the problems of taking on too much risk? We analyze whether executives' characteristics affect strategic choices due to bounded rationality, as proposed by the theory of upper echelons. The literature has thus far not empirically opened this black box. Relying on psychological economics, we develop hypotheses under which conditions expertise and gender can lead to biased information‐processing.

Research Findings/Insights:To test the hypotheses, we propose a two‐study methodology and take the financial crisis as a natural experimental setting. In Study 1, we analyze individual phenomena and show that under conditions of uncertainty, the processing of information by financial experts and men is worse than by non‐financial experts and women. In Study 2, we test these findings for organizational phenomena. We show that banks with a higher percentage of financial experts within TMTs perform better in stable environments, but are more negatively affected by the financial crisis.

Theoretical/Academic Implications:An important moderator within the theory of upper echelons is financial market discipline during turbulent periods, explaining why the performance of homogenous TMTs is volatile and why the performance of diverse TMTs is sustainable. The theory can be strengthened by including the insights of psychological economics as a micro‐foundation.

Practitioner/Policy Implications:For a sustainable performance, greater TMT diversity in public companies should be instituted by the board of directors.
PROMOTING INNOVATION IN THE ELECTRICITY INDUSTRY
Authors: Kiesling L. Lynne
Published: June 2010

Smart metering can bring significant benefits to electricity markets by allowing customers to reduce demand or increase supply when generation capacity is temporarily scarce. To reap the full efficiency and environmental benefits of this technology, regulators must allow price volatility and free entry into the market. The efficiency gains are enormous as both demand and supply will be affected by both temporary and longer‐lasting price changes. Experiments have shown the value of this approach.
MONEY STILL MATTERS – THE IMPLICATIONS OF M4X FOR QUANTITATIVE EASING
Authors: Smith David B.
Published: June 2010

It has been argued that quantitative easing (QE) is designed to prevent a collapse of broad money. However, the official M4 broad‐money measure was growing rapidly when QE was introduced. This figure was, though, exaggerated by artificial transactions within banking groups and some have suggested that broad money supply measures should exclude these transactions (M4X). This article tests whether the authorities are right to focus on M4X. It is concluded that M4X is more closely related to the wider economy than M4 but that the official M4X statistics need substantial improvement. The conclusions regarding QE generally are more nuanced and it is noted that the UK's fiscal profligacy is exacerbating the downturn in the private sector, despite politicians' claims to the contrary.
REGULATION AND THE NATURAL PROGRESS OF OPULENCE
Authors: Peltzman Sam
Published: June 2010

Adam Smith taught us how government regulation can counteract the market forces that produce economic growth. Here I explore a more complex interplay between regulation and economic growth. Regulation creates behavioural incentives that weaken or offset entirely the goal of the regulation. Growth produces many of the benefits ascribed to regulation while also hiding the costs and failures of regulation.
ECONOMIC SANCTIONS REVISITED: ADDITIONAL INSIGHTS INTO WHY THEY FAIL
Authors: Rarick Charles A. , Han Thaung
Published: June 2010

Economic sanctions have a poor track record in achieving their objectives. In most cases, they are ineffective in bringing about policy change, cause increased suffering in the sanctioned country and reduce opportunities for business. This paper provides additional insights into why sanctions fail by examining two overlooked factors: power–dependency theory and pressure for political stability.
LACK OF RIGOUR IN DEFENDING FAIRTRADE: SOME IMPORTANT CLARIFICATIONS OF A DISTORTING ACCOUNT – A REPLY TO PETER GRIFFITHS
Authors: Smith Alastair M.
Published: June 2010

Peter Griffiths claims to have undermined defensive accounts of Fairtrade by highlighting a lack of rigour in their methodology and textual construction. However, inter alia he has significantly distorted the meaning and relevance of a variety of contributions, not least that literature which he accuses others of failing to acknowledge.
Long‐term Performance of Greek IPOs
Authors: Thomadakis Stavros , Nounis Christos , Gounopoulos Dimitrios
Published: June 2010

We analyse the long‐run performance of 254 Greek IPOs that were listed during the period 1994–2002, computing buy‐and‐hold abnormal returns (BHAR) and cumulative abnormal returns (CAR) over 36 months of secondary market performance. The empirical results differ from international evidence and reveal long‐term overperformance that continues for a substantial interval after listing. Measuring these returns in calendar time, we find statistical significance with several of the benchmarks employed. We also find that long‐term overperformance is a feature of the mass of IPOs conducted during a pronounced IPO wave. Cross‐sectional regressions of long‐run performance disclose several significant factors. The study demonstrates that although Greek IPOs overperform the market for a longer period, underperformance eventually emerges, in line with much international evidence. Our interpretation is that the persistence of overperformance over a significant interval is due to excessive supply of issues during the ‘hot IPO period’. Results associated with pricing during the ‘hot IPO period’ indicate positive short‐ (1‐year), medium‐ (2‐year) and negative long‐term (3‐year) performance.
EFNS guidelines on diagnosis and management of neuromyelitis optica
Authors: Sellner J. , Boggild M. , Clanet M. , Hintzen R. Q. , Illes Z. , Montalban X. , Du Pasquier R. A. , Polman C. H. , Sorensen P. S. , Hemmer B.
Published: June 2010

Background and purpose:  Neuromyelitis optica (NMO) or Devic′s disease is a rare inflammatory and demyelinating autoimmune disorder of the central nervous system (CNS) characterized by recurrent attacks of optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM), which is distinct from multiple sclerosis (MS). The guidelines are designed to provide guidance for best clinical practice based on the current state of clinical and scientific knowledge.

Search strategy:  Evidence for this guideline was collected by searches for original articles, case reports and meta‐analyses in the MEDLINE and Cochrane databases. In addition, clinical practice guidelines of professional neurological and rheumatological organizations were studied.

Results:  Different diagnostic criteria for NMO diagnosis [Wingerchuk et al. Revised NMO criteria, 2006 and Miller et al. National Multiple Sclerosis Society (NMSS) task force criteria, 2008] and features potentially indicative of NMO facilitate the diagnosis. In addition, guidance for the work‐up and diagnosis of spatially limited NMO spectrum disorders is provided by the task force. Due to lack of studies fulfilling requirement for the highest levels of evidence, the task force suggests concepts for treatment of acute exacerbations and attack prevention based on expert opinion.

Conclusions:  Studies on diagnosis and management of NMO fulfilling requirements for the highest levels of evidence (class I–III rating) are limited, and diagnostic and therapeutic concepts based on expert opinion and consensus of the task force members were assembled for this guideline.
Embodied female experience through the lens of imagination
Authors: Green Sharon R.
Published: June 2010

Abstract:  In 1971, I made a film entitled Self Portrait of a Nude Model Turned Cinematographer in which I explore the objectifying ‘male’ gaze on my body in contrast to the subjective lived experience of my body. The film was a radical challenge to the gaze that objectifies woman – and thus imprisons her – which had hitherto dominated narrative cinema.

Since the objectification of women has largely excluded us from the privileged phallogocentric discourses, in this paper I hope to bring into the psychoanalytic dialogue a woman's lived experience. I will approach this by exploring how remembering this film has become a personally transformative experience as I look back on it through the lens of postmodern and feminist discourses that have emerged since it was made. In addition, I will explore how this process of imaginatively looking back on an artistic creation to generate new discourses in the present is similar to the transformative process of analysis. Lastly, I will present a clinical example, where my embodied countertransference response to a patient's subjection to the objectifying male gaze opens space for a new discourse about her body to emerge.
CEO Risk Incentives and Corporate Cash Holdings
Authors: Tong Zhenxu
Published: June 2010

Abstract:  This paper studies the implications of risk‐related agency theory on corporate cash holdings. Cash holdings are less risky but negative NPV projects from the investment perspective. Agency theory predicts that a risk‐averse CEO keeps more cash holdings to reduce firm risk at the expense of shareholder value. We use a measure of CEO risk incentives based on executive stock options, and study its relation with corporate cash holdings. We find that firms with higher CEO risk incentives have less cash holdings. We find that the value of cash holdings is higher in firms with higher CEO risk incentives. These findings are consistent with risk‐related agency theory.
Pollinator specificity, floral odour chemistry and the phylogeny of Australian sexually deceptiveChiloglottisorchids: implications for pollinator‐driven speciation
Authors: Peakall Rod , Ebert Daniel , Poldy Jacqueline , Barrow Russell A. , Francke Wittko , Bower Colin C. , Schiestl Florian P.
Published: June 2010

Featured paper: See Commentary p303
Impaired semantic processing during task‐set switching: Evidence from the N400 in rapid serial visual presentation
Authors: Vachon François , Jolicœur Pierre
Published: June 2010

The cognitive system is able to reconfigure mental resources flexibly to adapt to new a task. While task‐set switching is known to be detrimental to behavioral performance, less is known about the precise loci of these effects on stimulus processing. We measured event‐related potentials to explore the neural consequences of task‐set switching on semantic processing. We examined the context‐sensitive N400 component evoked by the second of two target words embedded in a rapid serial visual presentation under conditions that involved either a task‐set switch or no switching. Whereas the N400 was unaffected by the lag separating the targets in the absence of switching, it was delayed and attenuated in the switch condition when the targets were adjacent in the sequence. These findings indicate that task‐set reconfiguration temporarily prevents semantic activation and provide evidence for the nonautomaticity of semantic processing of words.
The central serotonin2Breceptor: a new pharmacological target to modulate the mesoaccumbens dopaminergic pathway activity
Authors: Auclair Agnès L. , Cathala Adeline , Sarrazin Frédéric , Depoortère Ronan , Piazza Pier Vincenzo , Newman‐Tancredi Adrian , Spampinato Umberto
Published: June 2010

J. Neurochem.(2010)114, 1323–1332.

The function of the serotonin2Breceptor (5‐HT2BR) in the mammalian brain is poorly characterized, especially with regard to its influence on dopamine (DA) neuron activity. Here, we assessed this issue by evaluating effects of 5‐HT2BRs ligands in the control of striatal and accumbal DA outflow, usingin vivomicrodialysis in halothane‐anesthetized rats, and amphetamine‐induced hyperlocomotion in vigil rats. The selective 5‐HT2BR antagonist 1‐[(2‐chloro‐3,4‐dimethoxyphenyl)methyl]‐2,3,4,9‐tetrahydro‐6‐methyl‐1H‐pyrido[3,4‐B]indole (LY 266097; 0.16 mg/kg, i.p.) had no influence on basal accumbal and striatal DA outflow but reduced significantly accumbal DA outflow when injected at 0.63 mg/kg. A significant reduction of basal DA outflow in the nucleus accumbens was also observed after i.p. administration of 0.16 mg/kg 2‐amino‐4‐(4‐fluoronaphth‐1‐yl)‐6‐isopropylpyrimidine, another selective 5‐HT2BR antagonist. In contrast, the 5‐HT2BR agonist α‐methyl‐5‐(2‐thienylmethoxy)‐1H‐indole‐3‐ethanamine (3 mg/kg, s.c.) had no influence on basal DA outflow in either brain region. The increase in striatal and accumbal DA outflow induced by the 5‐HT2CR inverse agonist 5‐methyl‐1‐(3‐pyridylcarbamoyl)‐1,2,3,5‐tetrahydropyrrolo[2,3‐f] indole (5 mg/kg, i.p.) was unaltered by LY 266097 (0.63 mg/kg) pre‐treatment. Conversely, LY 266097 (0.63 mg/kg) significantly diminished the increase in DA outflow induced by haloperidol (0.01 mg/kg, s.c.) or amphetamine (0.5 mg/kg, i.p.) in the nucleus accumbens, but not in the striatum. Amphetamine‐induced hyperlocomotion (1 mg/kg) was also attenuated by LY 266097 (0.63 mg/kg). These findings demonstrate that 5‐HT2BRs exert a facilitatory control on mesoaccumbens DA pathway activity, and suggest that they may constitute a new target for improved treatment of DA‐related neuropsychiatric disorders.
Staying active despite pain: Pain beliefs and experiences with activity‐related pain in patients with chronic musculoskeletal pain
Authors: Damsgård Elin , Dewar Anne , Røe Cecilie , Hamran Torunn
Published: June 2010

Scand J Caring Sci; 2011; 25; 108–116
 
Staying active despite pain: Pain beliefs and experiences with activity‐related pain in patients with chronic musculoskeletal pain

Objective:  Maintain a level of activity and exercise is advice often given to patients with chronic musculoskeletal pain, but many patients find physical activity painful and consequently hesitate to move. Disability seems to be associated with fear of pain and there is a need to enhance our understanding of patients’ beliefs and attitudes about how fear of pain affects physical activity and why some people are active despite their pain. The aim of this research was to understand thoughts and experiences about pain related to activity in patients with musculoskeletal disorders; the situations that promoted pain and if and how fear was expressed.

Methods:  Five women and five men, recruited from a larger survey on fear, pain and physical activity were interviewed. The interviews were analysed by qualitative methods for themes about participants’ pain and beliefs about pain.

Results:  By interpreting signals from the body, patients calculated and planned their daily life to stay active despite pain and participate in their social lives. Pain was a signal with diverse meanings which, with the influence of time, seemed to change from a sign of danger to a reminder to moderate their level of activity. By experimenting with different activities, patients learned how to gradually remain or become physically active.

Conclusion:  Patients strived to stay active despite pain. The interpretation of pain changed over time, from a threatening signal to a signal with diverse meanings.

Practice implications:  The findings provide insights that may improve the educational rehabilitation of patients with musculoskeletal pain.
Human stewardship or ruining cultural landscapes of the ancientTulawells, southern Ethiopia
Authors: TIKI WAKTOLE , OBA GUFU , TVEDT TERJE
Published: June 2010

This article uses the concepts of ‘human stewardship’ and ‘ruined landscape’ as a theoretical framework for analysing the community's perception of landscape change in the ancienttulawell system of Borana in southern Ethiopia. The ancienttulawell system, the main permanent water source, has been in operation for more than five centuries and it closely links human activity and the environment. The welfare of thetulawell system and the performance of the Borana pastoral system are directly related. Borana management of thetulawells uses concepts such aslaaf aadaa seeraaandlaaf badeto differentiate between ‘land managed by customary laws’ (hereafter human stewardship) and ‘lost’ or ‘ruined’ land (laaf bade). The cultural landscapes of the ancient wells have undergone changes from ecosystems featuring ‘human stewardship’ (before the 1960s), that is,laaf aadaa seeraato ‘ruined landscapes’ (after the 1960s), that is,laaf bade.Our interest is in understanding how the Borana perceive the impact of land use changes from these two conceptual perspectives. In group discussions, key informant interviews and household surveys across five of the nine well clusters, we found that the society described the changedtulacultural landscape in terms of drivers of well dynamics (i.e. use and disuse), break up of land use zonations, patterns of human settlement (traditional versus peri‐urban), expansion of crop cultivation, and changes in environmental quality. Using the two concepts, we analysed linkages between changing patterns of land use that transformed the system fromlaaf aadaa seeraa, which ensured human stewardship, tolaaf bade, which resulted in ruined landscapes. From these we analysed environmental narratives that showed how the society differentiated the past human stewardship that ensured sustainable landscape management from the present ruining oftulawell cultural landscapes.
Early Weichselian (MIS 5d and 5c) temperatures and environmental changes in northern Fennoscandia as recorded by chironomids and macroremains at Sokli, northeast Finland
Authors: ENGELS STEFAN , HELMENS KARIN F. , VÄLIRANTA MINNA , BROOKS STEPHEN J. , BIRKS H. JOHN B.
Published: June 2010

Engels, S., Helmens, K. F., Väliranta, M., Brooks, S. J. & Birks, H. J. B. 2010: Early Weichselian (MIS 5d and 5c) temperatures and environmental changes in northern Fennoscandia as recorded by chironomids and macroremains at Sokli, northeast Finland. Boreas, Vol. 39, pp. 689–704. 10.1111/j.1502‐3885.2010.00163.x. ISSN 0300‐9483.

A 25‐m‐long sediment record spanning the time from the Eemian to the Holocene was recovered from Sokli, northeast Finland. This study focuses on a 6‐m‐long sediment interval that is dated to the Early Weichselian period (MIS 5d and 5c) and consists of lacustrine and fluvial deposits. Using chironomid remains, botanical and zoological macroremains as well as sediment lithology, we were able to reconstruct past changes in the environment, including climate. The results indicate that the site was situated on a flood‐plain during the latter stages of MIS 5d (Herning Stadial) and that summer temperatures might have been ∼6 °C lower than at present. Although this value should be treated with caution, as numerical analysis shows that it has a very poor fit‐to‐temperature, this low reconstructed value concurs with several other reconstructions that are available from western Europe. During MIS 5c (Brørup interstadial), the depositional environment changed into a lake system, initially with stratification of the water and subsequently with complete mixing and a strong influence of streams. Both chironomid‐based and macroremain‐based temperature inferences indicate past July air temperatures that were significantly higher than at present. This result is in contrast to other (low‐resolution) reconstructions from northern Fennoscandia that indicate past temperatures 6–7 °C lower than present using fossil coleopteran assemblages. However, several central European sites indicate that there was a phase during the Brørup interstadial that was characterized by high summer temperatures, and a comparison between the high‐resolution reconstructions from western Europe and the results presented in this study suggests that the north–south July air temperature gradient between the mid‐ and high‐latitudes was much weaker during the Brørup interstadial than it is at present. High solar insolation values (particularly the obliquity) during the Brørup interstadial might explain the low summer temperature gradient over the European continent. A return to fluvial conditions occurred in the upper parts of the sediment sequence, and, after a brief interval of gyttja deposition under cooling conditions, the site became glaciated during MIS 5b.
Restoration of Plant–Pollinator Interactions: Pollination Neighborhood and Asymmetric Pollen Flow Between Restored Habitats in a Beetle‐Pollinated Aroid
Authors: García‐Robledo Carlos
Published: June 2010

Two processes globally threatening natural ecosystems are changes in land use and deforestation. Two methods used to restore threatened ecosystems are: (1) unassisted forest regeneration, which promotes the establishment of plants and fauna arriving from surrounding habitats and (2) assisted restoration, which involves the reconstruction of forests by planting native or exotic trees. Functional attributes, such as plant–pollinator interactions, are essential for ecosystem recovery. Unfortunately, information regarding the effect of restoration on pollination systems is limited. Forty years ago, a tropical cloud forest in Colombia was restored through unassisted forest regeneration, as well as by establishing monospecific plantations of the exotic Chinese ashFraxinus chinensis. The understories of both restoration strategies were colonized by the beetle‐pollinated aroidXanthosoma daguense.Using isolation‐by‐distance and multi‐strata mark‐recapture models, I estimated in each restoration strategy two fundamental pollination processes: (1) the magnitude ofX. daguensepollination neighborhood and (2) the directionality of pollen flow among plants colonizing both restoration strategies. In addition, I recorded pollinator visits and fruit production forX. daguensein each restored habitats. The pollination neighborhood ofX. daguensein the ash plantation is two times larger than its pollination neighborhood in natural regeneration. Inflorescences in the ash plantation donated 10 times more pollen to inflorescences in natural regeneration. Plants in natural regeneration produced two times more infructescences and more fruits than plants in ash plantation. Results show that the selection of different restoration strategies can alter two major components of plant–pollinator interactions in plants colonizing restored habitats, pollination neighborhoods, and pollen flow within the population.
Native Grass Establishment in Grassy Woodlands with Nutrient Enriched Soil and Exotic Grass Invasion
Authors: Lindsay Elizabeth A. , Cunningham Saul A.
Published: June 2010

Successful reintroduction of species to the ground‐layer of disturbed woodlands may require management of competition with adult plants and addressing the potential influence of soil nutrients. We investigated multiple factors that could potentially limit ground‐layer restoration in Eucalyptus melliodora–E. blakelyi grassy woodlands with modified ground‐layers. We established plots over ground‐layers varying in exotic annual and native perennial grass cover. First we investigated relationships between the existing vegetation and soil. Second, we evaluated whether the existing vegetation, soil fertility, and habitat factors, such as distance to trees, were barriers to native grass re‐establishment, by adding Poa labrillardieri and Bothriochloa macra seeds to plots with an intact ground‐layer, clipped ground‐layer, and plots cleared of all vegetation. Soil phosphorous had a positive relationship with exotic cover and a negative relationship with native cover. Clipping vegetation prior to seeding had a negative effect on P. labrillardieri emergence and no effect on B. macra, but survival of both species was greater when seeds were sown close to trees. Both species established better in cleared plots, indicating that competition can inhibit restoration. Bothriochloa macra establishment was low when soil carbon and C3 native grass cover were high. In contrast, B. macra established successfully in areas with high exotic cover and nutrient enriched soil. Poa labrillardieri seedling survival was low in all circumstances. We conclude that under comparable soil conditions it could be more difficult to re‐establish additional native grass species in woodland ground‐layers dominated by simplified native grass assemblages than those dominated by exotic annual grasses.
Seed Removal and Predation as Factors Affecting Seed Availability of Tree Species in Degraded Habitats and Restoration Plantings in Rainforest Areas of Queensland, Australia
Authors: Doust Susan J.
Published: June 2010

The post‐dispersal removal or predation of seeds of native tree species was investigated in Queensland, Australia, at degraded habitats and rainforest restoration sites where direct seeding might be used to facilitate tree regeneration (old fields or open habitats, lantana thicket, rainforest edge, and 5‐ and 10‐year‐old restoration plantings). Seed removal/predation was assessed in relation to tree seed weight and canopy density of the habitats during the wet season period. Results indicated that seed removal/predation imposes limitations on seed availability, particularly for small seeded species. In most situations, larger seeds were less removed/predated, most likely due to the more limited range of large seed consumers. The use of large, hard‐coated seeds may potentially reduce seed loss in open situations (from both seed removal and desiccation), unless large seed consumers frequent the site. Canopy cover exerted an influence on seed removal/predation, though trends varied in relation to site and the time of season. Broadcast sowing of seed under planted tree canopies at the more advanced stages of closure may in some areas result in higher seed removal/predation. Likewise, seeding in areas dominated by woody weeds may result in high seed losses to consumers such as rodents. Results suggested that undertaking direct seeding to coincide with the maximal period of fruit production may in some situations be beneficial to minimize seed loss. Overall, site context, canopy cover, and species selection appear to be important considerations when aiming to reduce loss of seeds to animal seed consumers in restoration work.
Screening of GABRB3 in French‐Canadian families with idiopathic generalized epilepsy
Authors: Lachance‐Touchette Pamela , Martin Caroline , Poulin Chantal , Gravel Micheline , Carmant Lionel , Cossette Patrick
Published: June 2010

Mutations in the GABRB3 have been recently associated with childhood absence epilepsy (CAE) in families from Honduras and Mexico. In this study, we aimed to determine the frequency of mutation in this gene in our cohort of families with CAE and other related idiopathic generalized epilepsy (IGE) syndromes. We screened the open reading frame of GABRB3 in 183 French‐Canadian individuals with IGE, including 88 with CAE. A total of nine single nucleotide polymorphisms (SNPs) have been identified, five of which are novel. The previously described P11S missense mutation was found in three affected and one unaffected individuals from a French‐Canadian family. However, the P11S variant was also found in one of our 190 control individuals of French‐Canadian origin, suggesting that this variant is rather a rare polymorphism in this population. Further screening of other IGE cohorts from various ethnic origins would help to confirm the association between this rare functional variant and epilepsy.
BOLD signal changes preceding negative responses in EEG‐fMRI in patients with focal epilepsy
Authors: Rathakrishnan Rahul , Moeller Friederike , Levan Pierre , Dubeau Francois , Gotman Jean
Published: June 2010

Purpose: In simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI), increased neuronal activity from epileptiform spikes commonly elicits positive blood oxygenation level–dependent (BOLD) responses. Negative responses are also occasionally seen and have not been explained. Recent studies describe BOLD signal changes before focal EEG spikes. We aimed to systematically study if the undershoot of a preceding positive response might explain the negative BOLD seen in the focus.

Methods: Eighty‐two patients with focal epilepsy who underwent EEG‐fMRI at 3T were retrospectively studied. Studies with a focal negative BOLD response in the region of the spike field were reanalyzed using models with hemodynamic response functions (HRFs) peaking from −9 to +9 s around the spike.

Results: Eight patients met the inclusion criteria, showing negative BOLD responses in the spike field on standard analysis. None had positive BOLD responses immediately adjacent to the areas of deactivation. Regions of deactivation were found to have congruent preceding positive responses in two cases. These early activations were seen at the combined maps of −5 to −9 s.

Discussion: This study indicates that in a small proportion of patients with focal epilepsy in whom the standard analysis reveals focal negative responses, an earlier positive BOLD response is probably the cause. The origin of negative BOLD signal changes in the focus as a result of an epileptic event remains, however, unexplained in most of the patients in whom it occurs.
Autoantibodies to glutamic acid decarboxylase in patients with epilepsy are associated with low cortical GABA levels
Authors: Stagg Charlotte J. , Lang Bethan , Best Jonathan G. , McKnight Karen , Cavey Ana , Johansen‐Berg Heidi , Vincent Angela , Palace Jacqueline
Published: June 2010

Antibodies to glutamic acid decarboxylase (GAD), the major pathway for the synthesis of γ‐aminobutyric acid (GABA) in humans, are found at elevated levels in a subgroup of patients with chronic epilepsy. To test whether the antibodies were associated with changes in cortical GABA levels we used magnetic resonance spectroscopy. Four patients with epilepsy and high serum GAD antibody levels (107–6,200 units/ml) and 10 healthy controls were recruited. A 3T GABA‐optimized spectrum was obtained from a reproducible voxel in the cortex. Compared to the control group, the patient group had significantly lower GABA concentrations within the cortex. Demonstration of an association between high serum GAD antibodies and low cortical GABA levels in patients with epilepsy suggests that GAD antibodies are, at least, a marker of a specific disease process and support a role for immune‐mediated GABAergic dysfunction.
Partial epilepsy with antecedent febrile seizures and seizure aggravation by antiepileptic drugs: Associated with loss of function of Nav1.1
Authors: Liao Wei‐Ping , Shi Yi‐Wu , Long Yue‐Sheng , Zeng Yang , Li Tian , Yu Mei‐Juan , Su Tao , Deng Ping , Lei Zhi‐Gang , Xu Shu‐Jun , Deng Wei‐Yi , Liu Xiao‐Rong , Sun Wei‐Wen , Yi Yong‐Hong , Xu Zao C. , Duan Shumin
Published: June 2010

Purpose:  Generalized epilepsy with febrile seizures plus (GEFS+) and severe myoclonic epilepsy in infancy (SMEI) are associated with sodium channel α‐subunit type‐1 gene (SCN1A) mutations. Febrile seizures and partial seizures occur in both GEFS+ and SMEI; sporadic onset and seizure aggravation by antiepileptic drugs (AEDs) are features of SMEI. We thus searched gene mutations in isolated cases of partial epilepsy with antecedent FS (PEFS+) that showed seizure aggravations by AEDs.

Methods:  Genomic DNA from four patients was screened for mutations in SCN1A, SCN2A, SCN1B, and GABRG2 using denaturing high‐performance liquid chromatography (dHPLC) and sequencing. Whole‐cell patch clamp analysis was used to characterize biophysical properties of two newly defined mutants of Nav1.1 in tsA201 cells.

Results:  Two heterozygous de novo mutations of SCN1A (R946H and F1765L) were detected, which were proven to cause loss of function of Nav1.1. When the functional defects of mutants reported previously are compared, it is found that all mutants from PEFS+ have features of loss of function, whereas GEFS+ shows mild dysfunction excluding loss of function, coincident with mild clinical manifestations. PEFS+ is similar to SMEI clinically with possible AED‐induced seizure aggravation and biophysiologically with features of loss of function, and different from SMEI by missense mutation without changes in hydrophobicity or polarity of the residues.

Conclusions:  Isolated milder PEFS+ may associate with SCN1A mutations and loss of function of Nav1.1, which may be the basis of seizure aggravation by sodium channel–blocking AEDs. This study characterized phenotypes biologically, which may be helpful in understanding the pathophysiologic basis, and further in management of the disease.
Oral pregabalin as an add‐on treatment for status epilepticus
Authors: Novy Jan , Rossetti Andrea O.
Published: June 2010

Oral antiepileptic drugs (AEDs) represent possible add‐on options in refractory status epilepticus (SE). In this setting, pregabalin (PGB) has not been reported before. Over the last 42 months, we identified 11 SE episodes (10 patients) treated with PGB in our hospital. Its use was prompted by the favorable pharmacokinetic profile, devoid of drug‐drug interactions. The patients mostly had refractory, partial SE. Only two patients were managed in the intensive care unit (ICU). We found a definite electroclinical response in 5 of 11, already evident 24 h after PGB introduction, and a possible response (concomitantly with other AEDs) in 3 of 11 of the episodes; 3/11 did not respond. The treatment was well tolerated. Partial SE appeared to better respond than generalized convulsive SE. PGB appears to be an interesting option as add‐on treatment in refractory partial SE.
Naltrexone Selectively Elevates GABAergic Neuroactive Steroid Levels in Heavy Drinkers With the ASP40 Allele of the OPRM1 Gene: A Pilot Investigation
Authors: Ray Lara A. , Hutchison Kent E. , Ashenhurst James R. , Morrow A. Leslie
Published: June 2010

Background: Preclinical studies have implicated GABAergic neurosteroids in behavioral responses to alcohol. Naltrexone is thought to blunt the reinforcing effects of alcohol, and a few studies have found that the effects of naltrexone are moderated by the Asn40Asp polymorphisms of theOPRM1gene. The present study seeks to integrate these lines of research by testing (i) the moderating role of the functional Asn40Asp polymorphism of theOPRM1gene on naltrexone‐induced alternations in GABAergic neurosteroid levels, namely (3α,5α)‐3‐hydroxypregnan‐20‐one (allopregnanolone, ALLO); and (ii) the combined effects of naltrexone or genotype with alcohol administration on neurosteroid levels in a sample of at‐risk drinkers.

Methods: Participants were 32 (9 females) nontreatment‐seeking heavy drinkers who completed a placebo‐controlled laboratory study of naltrexone (50 mg/d for 3 days) and provided complete sets of serum samples for ALLO assays before and after alcohol administration under both naltrexone and placebo conditions.

Results: Naltrexone treatment raised ALLO levels among carriers of the Asp40 allele, but not homozygotes for the Asn40 allele. The Asn40Asp polymorphism did not moderate effects of naltrexone on cortisol levels. Ethanol infusion modestly reduced ALLO levels in all subjects, independent of genotype or naltrexone exposure.

Conclusions: Naltrexone increased ALLO levels among individuals with the Asn40Asp allele suggesting a potential neurosteroid contribution to the neuropharmacological effects of naltrexone among Asp40 carriers.
Complete Revascularization in Patients Undergoing Multivessel PCI is an Independent Predictor of Improved Long‐term Survival
Authors: LEHMANN RALF , FICHTLSCHERER STEPHAN , SCHÄCHINGER VOLKER , HELD LAURA , HOBLER CAROLA , BAIER GREGOR , ZEIHER ANDREAS M. , SPYRIDOPOULOS IOAKIM
Published: June 2010

Background: The prognostic relevance of complete revascularization (CR) in patients with multivessel coronary artery disease (MV‐CAD) has been established so far for surgical treatment strategies rather than for percutaneous coronary revascularization (PCI). In addition, different definitions of CR have further complicated the interpretation of clinical studies.

Methods: Procedural characteristics and long‐term overall survival were assessed in 679 consecutive “all‐comer” patients, who underwent PCI in at least two main vessels. We adapted three definitions of CR from the coronary artery bypass grafting (CABG) trials. CR was achieved if following MV‐PCI one of the three criteria was met: (1) no residual stenosis in a main coronary vessel, (2) no residual stenosis in any coronary segment, or (3) no residual stenosis in the left anterior descending (LAD) and at least one further main branch. The main objective was the evaluation of predictors of incomplete revascularization and the prognostic impact of CR in MV‐PCI patients.

Results: CR was achieved in 76%, 67%, and 95%, respectively, (definitions 1–3). Patients without CR were older, had a lower ejection fraction, and presented more often with acute coronary syndromes (ACS). Clinical long‐term follow‐up regarding survival was available in 664 patients (98%) with a mean follow‐up of 2.5 ± 1.6 years. Independent of the specific definition, CR was associated with a reduced long‐term mortality by approximately 50%. After adjusting for relevant baseline parameters, only absence of residual stenosis in all coronary segments remained as an independent predictor of long‐term prognosis (hazard ratio [HR]= 0.51, 95% confidence interval [CI]: 0.28–0.93; P = 0.025).

Conclusions: CR of all coronary segments is associated with improved overall survival after MV‐PCI. (J Interven Cardiol 2010;23:256–263)
Role of a Streamer‐like Coronary Thrombus in the Genesis of Unstable Angina
Authors: UCHIDA YASUMI , UCHIDA YASUTO , KANAI MASAHITO , SAKURAI TAKESHI , OSHIMA TOMOMITSU , SHIRAI SEIICHIRO
Published: June 2010

Introduction: It is generally believed that the coronary occlusion occurs at the site of plaque disruption in acute coronary syndromes. An exceptional mechanism of coronary occlusion, namely a streamer‐like thrombus (SLT) originating in a nonstenotic lesion extended distally to obstruct a just distal nondisrupted stenotic segment, was found by angioscopy in patients with unstable angina (UA). This study was carried out to examine the incidence of this phenomenon and its relationship to the subtypes of UA.

Methods: The culprit coronary artery was investigated by angioscopy in successive 48 patients (mean ± SE age, 61.0 ± 2.3 years; 10 females and 38 males) with UA.

Results: SLT originating in a nonstenotic lesion extended distally, and obstructed the just distal most stenotic segment (DMSS) by its tail in 11 patients (eight with class III and three with class II according to Braunwald's classification). Recurrent anginal attacks were observed in all. The nonstenotic lesion in which the SLT originated was a disrupted yellow plaque in most cases. The SLT was frequently red and yellow in a mosaic pattern, indicating a mixture of fresh thrombus and plaque debris. The plaques that constructed the DMSS were not disrupted. Angiographically, the SLT was not detectable and the entry of the DMSS showed a “tapering” configuration.

Conclusions: Obstruction of the DMSS by the tail of SLT originating in a nonstenotic lesion is another mechanism of UA. Therefore, treatment of both the nonstenotic lesion and DMSS is needed to prevent recurrent thrombus formation and consequent reattacks. (J Interven Cardiol 2010;23:216–222)