bluuebunny/crossref_metadata_2025 huggingface dataset:
Oryza sh4 gene homologue represents homoeologous genomic copies in polyploid Echinochloa
Authors: AOKI DAISUKE , YAMAGUCHI HIROFUMI
Published: August 2009

The coding region sequence of the Oryza sh4 gene homologue in Echinochloa was analyzed in relation to the shattering nature of spikelets and the phylogeny of homologue copies in the Asian annual polyploidy Echinochloa. The Sh4 homoeologue copies were detected in Echinochloa oryzicola, Echinochloa crus‐galli, Echinochloa stagnina, Echinochloa colona, and Echinochloa crus‐pavonis. Amino acid sequence differences did not lead to a functional change in the sh4 gene between the shattering and non‐shattering types in E. crus‐galli, E. oryzicola, and E. colona. A phylogenetic analysis of the homoeologous copy sequences indicated a genomic relationship between the Asian Echinochloa species and supported that the allohexaploid E. crus‐galli shares two genomes with its parental donor, E. oryzicola. The Asian perennial tetraploid species, E. stagnina, shares one genome with E. oryzicola and possesses an unknown genome. Echinochloa crus‐pavonis, from the New World, shows a close affinity of two genomes with E. crus‐galli and E. oryzicola. Echinochloa colona showed distant affinities in all homoeologous copies.
Effects of duck activities on a weed community under a transplanted rice–duck farming system in southern China
Authors: ZHANG JIA‐EN , XU RONGBAO , CHEN XIN , QUAN GUOMING
Published: August 2009

Rice–duck farming is one of the traditional, but current and gradually popularized, ecological farming techniques for paddy rice production in China. In comparison to rice monoculture farming, we investigated a weed community and weed infestation in a transplanted rice–duck farming system and examined the effects of duck activities on the weeds. Three treatments were imposed in the experiment: a rice–duck coculture with duck grazing and disturbance effects, a rice–duck coculture with duck disturbance effects only, and a control (rice monoculture, no duck effects). Rice seedlings were nursed and transplanted in this experiment. The total number of weed species was significantly lower in the treatment with both duck grazing and disturbance and in the treatment with duck disturbance only than in the monoculture rice treatment (control). The Shannon‐Wiener Biodiversity Index of the weed species decreased but the Pielou Evenness Index increased in both treatments with ducks compared to the monoculture control. Sorensen's coefficient of similarity of the weed communities was low between the treatments with ducks and the monoculture control, implying that the weed communities diverged. The total density and biomass of the weed community in both the treatments with ducks were significantly lower compared to the monoculture control. However, compared to the rice monoculture control, the weed biomass was reduced by 98% in the treatment with duck grazing and disturbance and by 84% in the treatment with duck disturbance only, implying that only 14% of the weeds were controlled by duck grazing and that 84% of the weed biomass was inhibited by duck activities in the rice field with ducks. The rice grain yield increased in the treatments with ducks compared to the control. The results suggested that duck activities, like grazing weeds and disturbance of the soil and water, had a significant effect on the weed community structure and that weeds could be well controlled without herbicide application under a rice–duck farming system.
Transcatheter coil embolization for patent ductus arteriosus in the elderly: Report of a case and review of the published work
Authors: Aoyagi Shigeaki , Chihara Shingo , Fukunaga Shuji , Mori Ryusuke , Suda Kenji
Published: August 2009

Patent ductus arteriosus is the third most common congenital cardiovascular anomaly, however, it is rarely found in the elderly. We describe a case of patent ductus arteriosus in a 72‐year‐old woman in whom patent ductus arteriosus was successfully managed by transcatheter coil embolization. The patient had been diagnosed with a heart murmur for the first time 1 year earlier at the age of 71. She was asymptomatic but a continuous murmur was heard. Cardiac catheterization revealed migration of a catheter from the main pulmonary artery into the descending aorta through a patent ductus arteriosus and a significant step‐up of oxygen saturation in the main pulmonary artery with a pulmonary‐to‐systemic flow ratio of 1.68. Aortograms demonstrated a communication between the aorta and the pulmonary artery through a patent ductus arteriosus with a minimal diameter of 3.7 mm. Transcatheter coil embolization of the patent ductus arteriosus was successfully carried out with two 0.052‐inch‐diameter Gianturco coils. Doppler echocardiographic study confirmed no residual shunt in the main pulmonary artery after the procedure. Non‐surgical transcatheter occlusion using coil embolization appears to be an effective and minimally invasive technique for treatment of patent ductus arteriosus in the elderly.
Predation has a greater impact in less productive environments: variation in roe deer, Capreolus capreolus, population density across Europe
Authors: Melis Claudia , Jędrzejewska Bogumiła , Apollonio Marco , Bartoń Kamil A. , Jędrzejewski Włodzimierz , Linnell John D.C. , Kojola Ilpo , Kusak Josip , Adamic Miha , Ciuti Simone , Delehan Ivan , Dykyy Ihor , Krapinec Krešimir , Mattioli Luca , Sagaydak Andrey , Samchuk Nikolay , Schmidt Krzysztof , Shkvyrya Maryna , Sidorovich Vadim E. , Zawadzka Bernadetta , Zhyla Sergey
Published: August 2009

Aim  We aimed to describe the large‐scale patterns in population density of roe deer Caprelous capreolus in Europe and to determine the factors shaping variation in their abundance.

Location  Europe.

Methods  We collated data on roe deer population density from 72 localities spanning 25° latitude and 48° longitude and analysed them in relation to a range of environmental factors: vegetation productivity (approximated by the fraction of photosynthetically active radiation) and forest cover as proxies for food supply, winter severity, summer drought and presence or absence of large predators (wolf, Canis lupus, and Eurasian lynx, Lynx lynx), hunter harvest and a competitor (red deer, Cervus elaphus).

Results  Roe deer abundance increased with the overall productivity of vegetation cover and with lower forest cover (sparser forest cover means that a higher proportion of overall plant productivity is allocated to ground vegetation and thus is available to roe deer). The effect of large predators was relatively weak in highly productive environments and in regions with mild climate, but increased markedly in regions with low vegetation productivity and harsh winters. Other potentially limiting factors (hunting, summer drought and competition with red deer) had no significant impact on roe deer abundance.

Main conclusions  The analyses revealed the combined effect of bottom‐up and top‐down control on roe deer: on a biogeographical scale, population abundance of roe deer has been shaped by food‐related factors and large predators, with additive effects of the two species of predators. The results have implications for management of roe deer populations in Europe. First, an increase in roe deer abundance can be expected as environmental productivity increases due to climate change. Secondly, recovery plans for large carnivores should take environmental productivity and winter severity into account when predicting their impact on prey.
Dynamic macroecology on ecological time‐scales
Authors: Fisher Jonathan A. D. , Frank Kenneth T. , Leggett William C.
Published: August 2009

Aim The discipline of macroecology is increasingly being regarded as an effective vehicle for the evaluation of recent population‐ to ecosystem‐level responses to widespread human and environmental influences. However, due to the prevalent use of time‐averaged and cumulative data in macroecological analyses, the majority of the patterns that emerge from research in this field can be regarded as static. Here we review the application of dynamic macroecological analyses to changes in relationships between macroecological variables on seasonal to decadal scales. We illustrate the strength of this perspective for documenting changing patterns and testing hypotheses related to these dynamics on ecological time‐scales.

Location Studies were compiled and reviewed from terrestrial and aquatic ecosystems.

Methods We review examples of temporal changes in macroecological patterns driven by recent anthropogenic influences and environmental change.

Results The dynamic nature of macroecological patterns on ecological time‐scales has been revealed in recent years across a wide range of ecosystems, largely through the development, maintenance and analysis of biotic and environmental monitoring time series. The resultant analyses complement examinations of dynamics over evolutionary time and have similarly revealed that static portrayals can conceal important temporal dynamics that underlie the patterns of interest. As a consequence, static depictions, resting as they do on comparative analyses in which the validity of space‐for‐time substitutions is assumed, may be of limited use for testing hypotheses related to the mechanisms underlying the patterns revealed and, by extension, the development of reliable predictions of future states.

Main conclusions Recent dynamic macroecological analyses have demonstrated the utility of combined spatial and temporal replication, and have contributed to hypothesis testing related to the mechanistic processes underlying changes in macroecological patterns on ecological time‐scales. We suggest four specific avenues of future research to further the development and application of temporal approaches on similar time‐scales within the field of macroecology.
Deterministic Importance Sampling with Error Diffusion
Authors: Szirmay‐Kalos László , Szécsi László
Published: August 2009

This paper proposes a deterministic importance sampling algorithm that is based on the recognition that delta‐sigma modulation is equivalent to importance sampling. We propose a generalization for delta‐sigma modulation in arbitrary dimensions, taking care of the curse of dimensionality as well. Unlike previous sampling techniques that transform low‐discrepancy and highly stratified samples in the unit cube to the integration domain, our error diffusion sampler ensures the proper distribution and stratification directly in the integration domain. We also present applications, including environment mapping and global illumination rendering with virtual point sources.
Anomalous Dispersion in Predictive Rendering
Authors: Weidlich Andrea , Wilkie Alexander
Published: August 2009

In coloured media, the index of refraction does not decrease monotonically with increasing wavelength, but behaves in a quite non‐monotonical way. This behaviour is called anomalous dispersion and results from the fact that the absorption of a material influences its index of refraction.

So far, this interesting fact has not been widely acknowledged by the graphics community. In this paper, we demonstrate how to calculate the correct refractive index for a material based on its absorption spectrum with the Kramers‐Kronig relation, and we discuss for which types of objects this effect is relevant in practice.
Efficient and Accurate Rendering of Complex Light Sources
Authors: Kniep S. , Häring S. , Magnor M.
Published: August 2009

We present a new method for estimating the radiance function of complex area light sources. The method is based on Jensen's photon mapping algorithm. In order to capture high angular frequencies in the radiance function, we incorporate the angular domain into the density estimation. However, density estimation in position‐direction space makes it necessary to find a tradeoff between the spatial and angular accuracy of the estimation. We identify the parameters which are important for this tradeoff and investigate the typical estimation errors. We show how the large data size, which is inherent to the underlying problem, can be handled. The method is applied to different automotive tail lights. It can be applied to a wide range of other real‐world light sources.
Texture Design and Draping in 2D Images
Authors: Winnemöller H. , Orzan A. , Boissieux L. , Thollot J.
Published: August 2009

We present a complete system for designing and manipulating regular or near‐regular textures in 2D images. We place emphasis on supporting creative workflows that produce artwork from scratch. As such, our system provides tools to create, arrange, and manipulate textures in images with intuitive controls, and without requiring 3D modeling. Additionally, we ensure continued, non‐destructive editability by expressing textures via a fully parametric descriptor. We demonstrate the suitability of our approach with numerous example images, created by an artist using our system, and we compare our proposed workflow with alternative 2D and 3D methods.
Packet‐based Hierarchal Soft Shadow Mapping
Authors: Yang Baoguang , Feng Jieqing , Guennebaud Gaël , Liu Xinguo
Published: August 2009

Recent soft shadow mapping techniques based on back‐projection can render high quality soft shadows in real time. However, real time high quality rendering of large penumbrae is still challenging, especially when multilayer shadow maps are used to reduce single light sample silhouette artifact. In this paper, we present an efficient algorithm to attack this problem. We first present a GPU‐friendly packet‐based approach rendering a packet of neighboring pixels together to amortize the cost of computing visibility factors. Then, we propose a hierarchical technique to quickly locate the contour edges, further reducing the computation cost. At last, we suggest a multi‐view shadow map approach to reduce the single light sample artifact. We also demonstrate its higher image quality and higher efficiency compared to the existing depth peeling approaches.
Fast Global Illumination on Dynamic Height Fields
Authors: Nowrouzezahrai Derek , Snyder John
Published: August 2009

We present a real‐time method for rendering global illumination effects from large area and environmental lights on dynamic height fields. In contrast to previous work, our method handles inter‐reflections (indirect lighting) and non‐diffuse surfaces. To reduce sampling, we construct one multi‐resolution pyramid for height variation to compute direct shadows, and another pyramid for each indirect bounce of incident radiance to compute inter‐reflections. The basic principle is to sample the points blocking direct light, or shedding indirect light, from coarser levels of the pyramid the farther away they are from a given receiver point. We unify the representation of visibility and indirect radiance at discrete azimuthal directions (i.e., as a function of a single elevation angle) using the concept of a “casting set” of visible points along this direction whose contributions are collected in the basis of normalized Legendre polynomials. This analytic representation is compact, requires no precomputation, and allows efficient integration to produce the spherical visibility and indirect radiance signals. Sub‐sampling visibility and indirect radiance, while shading with full‐resolution surface normals, further increases performance without introducing noticeable artifacts. Our method renders 512×512 height fields (> 500K triangles) at 36Hz.
Hierarchical Image‐Space Radiosity for Interactive Global Illumination
Authors: Nichols Greg , Shopf Jeremy , Wyman Chris
Published: August 2009

We introduce image‐space radiosity and a hierarchical variant as a method for interactively approximating diffuse indirect illumination in fully dynamic scenes. As oft observed, diffuse indirect illumination contains mainly low‐frequency details that do not require independent computations at every pixel. Prior work leverages this to reduce computation costs by clustering and caching samples in world or object space. This often involves scene preprocessing, complex data structures for caching, or wasted computations outside the view frustum. We instead propose clustering computations in image space, allowing the use of cheap hardware mipmapping and implicit quadtrees to allow coarser illumination computations. We build on a recently introduced multiresolution splatting technique combined with an image‐space lightcut algorithm to intelligently choose virtual point lights for an interactive, one‐bounce instant radiosity solution. Intelligently selecting point lights from our reflective shadow map enables temporally coherent illumination similar to results using more than 4096 regularly‐sampled VPLs.
Interactive Global Photon Mapping
Authors: Fabianowski B. , Dingliana J.
Published: August 2009

We present a photon mapping technique capable of computing high quality global illumination at interactive frame rates. By extending the concept of photon differentials to efficiently handle diffuse reflections, we generate footprints at all photon hit points. These enable illumination reconstruction by density estimation with variable kernel bandwidths without having to locate the k nearest photon hits first. Adapting an efficient BVH construction process for ray tracing acceleration, we build photon maps that enable the fast retrieval of all hits relevant to a shading point. We present a heuristic that automatically tunes the BVH build's termination criterion to the scene and illumination conditions. As all stages of the algorithm are highly parallelizable, we demonstrate an implementation using NVidia's CUDA manycore architecture running at interactive rates on a single GPU. Both light source and camera may be freely moved with global illumination fully recalculated in each frame.
BTF Compression via Sparse Tensor Decomposition
Authors: Ruiters Roland , Klein Reinhard
Published: August 2009

In this paper, we present a novel compression technique for Bidirectional Texture Functions based on a sparse tensor decomposition. We apply the K‐SVD algorithm along two different modes of a tensor to decompose it into a small dictionary and two sparse tensors. This representation is very compact, allowing for considerably better compression ratios at the same RMS error than possible with current compression techniques like PCA, N‐mode SVD and Per Cluster Factorization. In contrast to other tensor decomposition based techniques, the use of a sparse representation achieves a rendering performance that is at high compression ratios similar to PCA based methods.
Spatial Directional Radiance Caching
Authors: Gassenbauer Václav , Křivánek Jaroslav , Bouatouch Kadi
Published: August 2009

We present a new approach for accelerated global illumination computation in scenes with glossy surfaces. Our algorithm combines sparse illumination computation used in the radiance caching algorithm with BRDF importance sampling. To make this approach feasible, we extend the idea of lazy illumination evaluation, used in the caching approaches, from the spatial to the directional domain. Using importance sampling allows us to apply caching not only on low‐gloss but also on shiny materials with high‐frequency BRDFs, for which the radiance caching algorithm breaks down.
The Use of Precomputed Triangle Clusters for Accelerated Ray Tracing in Dynamic Scenes
Authors: Garanzha Kirill
Published: August 2009

In this paper we present a hybrid algorithm for building the bounding volume hierarchy (BVH) that is used in accelerating ray tracing of animated models. This algorithm precomputes densely packed clusters of triangles on surfaces. Folowing that, a set of clusters is used to rebuild the BVH in every frame. Our approach utilizes the assumption that groups of connected triangles remain connected throughout the course of the animation. We introduce a novel heuristic to create triangle clusters that are designed for high performance ray tracing. This heuristic combines the density of connectivity, geometric size and the shape of the cluster.

Our approach accelerates the BVH builder by an order of magnitude rebuilding only the set of clusters that is much smaller than the original set of triangles. The speed‐up is achieved against a ‘brute‐force’ BVH builder that repartitions all triangles in every frame of animation without using any pre‐clustering. The rendering performance is not affected when a cluster contains a few dozen triangles. We demonstrate the real‐time/interactive ray tracing performance for highly‐dynamic complex models.
Motion based Painterly Rendering
Authors: Lee H. , Lee C. H. , Yoon K.
Published: August 2009

Previous painterly rendering techniques normally use image gradients for deciding stroke orientations. Image gradients are good for expressing object shapes, but difficult to express the flow or movements of objects. In real painting, the use of brush strokes corresponding to the actual movement of objects allows viewers to recognize objects' motion better and thus to have an impression of the dynamic. In this paper, we propose a novel painterly rendering algorithm to express dynamic objects based on their motion information. We first extract motion information (magnitude, direction, standard deviation) of a scene from a set of consecutive image sequences from the same view. Then the motion directions are used for determining stroke orientations in the regions with significant motions, and image gradients determine stroke orientations where little motion is observed. Our algorithm is useful for realistically and dynamically representing moving objects. We have applied our algorithm for rendering landscapes. We could segment a scene into dynamic and static regions, and express the actual movement of dynamic objects using motion based strokes.
Nonlinear Damping Identification in Precast Prestressed Reinforced Concrete Beams
Authors: Franchetti P. , Modena C. , Feng M.Q.
Published: August 2009

Abstract:  This article presents a damage detection method for prestressed reinforced concrete (PRC) elements based on free vibration tests and nonlinear damping identification. Integrated static and dynamic experiments were carried out on three precast PRC beam specimens. The static loading induced different levels of damage to the beams. At each damage level, impulsive loading was applied to the beams and the free vibration response was measured. The dynamic response data were processed using different methods including the multi‐input multi‐output (MIMO) curve fitting and the Hilbert transform techniques. A strong correlation is observed between the level of concrete damage (cracks) and the amount of nonlinear energy dissipation that can be modeled by means of quadratic damping. The nonlinear damping can be extracted from the free vibration response for each vibration mode. The proposed method is suited for quality control when manufacturing precast PRC members, and can be further extended for in situ detection of damage in concrete structures under ambient vibration.
OPTIMAL SETS OF CANDIDATES
Authors: FEDDERKE JOHANNES
Published: August 2009

We consider the optimal choice set of candidates standing for elected office. The decision dimensions are in the number of candidates standing for election, the experiential base of the candidates standing for election as measured by the length of prior experience held by the candidates, and the proportion of candidates with such prior experience. We find that while there are benefits that accrue to having a larger choice, the optimal number of candidates is strictly finite. Second, to justify an increase in the optimal length of prior experience requires strong increases in the ratio of benefits that accrue from additional experience to the cost of abuse of privilege. The conditions under which an increase in the length of prior experience can be justified are where the cost associated with abuse of privilege is negligible. This would require the development of appropriate formal (legal and constitutional) and informal (civil society) institutions that ensure that abuse of office remains negligible. Finally, we allow the number of electoral candidates, the length of their prior experience, as well as the proportion of candidates with experience to vary. Under this choice problem optimal pairings of length of experience and the proportion of candidates with prior experience may not exist. Hence, societies may be condemned to suboptimality even should the political system prove to be amenable to change, rendering disaffection endemic to the political system.
The time and effort in taking care for children with profound intellectual and multiple disabilities: a study on care load and support
Authors: Tadema Annemarie C. , Vlaskamp Carla
Published: August 2009

Accessible summary

It is not easy for parents to care for a child with profound intellectual and multiple disabilities (PIMD). But we do not know how much effort it actually takes. If we want to help the parents, it is good to understand what it is they need to do and how much time that takes.

We asked parents with what basic care tasks they had to help their child. And how much time that took them. We also asked parents if they had help from friends and relatives. We also wanted to know if professionals could really help to make the lives of parents a bit easier. There were 133 parents who answered all those questions.

What they told us was important. They said:

 Our children are very dependent on us. We have to help them with getting up, getting dressed, eating and drinking, and so on. And that will never stop, even if they grow older.

 Some of us still have to get up night after night to look after the child. This is very tiring. To be up every night is really a burden.

 We learn to live with the needs that our children have. It is more difficult for younger parents than it is for parents with an older child.

 The support of professionals from special educational centre’s is very important for us. To us, it is even more important than help from friends.

Raising children with profound intellectual and multiple disabilities is considered to be extremely difficult for parents, but figures on the content and amount of time needed for the caring task of parents is lacking. Data on what the caring task actually means (in terms of amount of time and type of task) is needed to be able to understand the parents’ support needs. A questionnaire was developed in order to collect information about both the caring task and the level of parental burden concerning health‐related tasks and basic need tasks such as eating and drinking, dressing and sleeping. Furthermore, the level of support parents experience from friends, relatives and special services is included and the use of special aids and resources is taken into account. A total of 133 parents completed the questionnaire. Most children are dependent on them for meeting all their basic needs and have several health problems. Significant relationships were found between the number of times parents have to get up at night and the level of burden at night, and between the days a child stayed in hospital and the level of parental burden. The results indicate that the caring task places heavy demands on parents. Professional support is alleviating and extremely important for parents. The caring task is not necessarily indicative for the subjective burden parents experience. Parents of young children express higher levels of burden than parents of older children.
Unconscious priming of a no‐go response
Authors: Hughes Gethin , Velmans Max , De Fockert Jan
Published: August 2009

Although previous findings suggest that motor preparation can be initiated unconsciously, there is some debate as to whether inhibitory control can occur unconsciously. Results from research involving response conflict points to an association between inhibitory control and conscious awareness. However, no previous research has assessed whether unconscious information can influence brain activity correlates of inhibition when a response must be completely withheld. We recorded event‐related potentials (ERPs) in a go/no‐go task with subliminal primes and demonstrated that inhibition‐related ERP components were modulated as a function of the congruency of the primes. Furthermore, these ERP modulations were directly related to the extent to which participants' performance was influenced by the primes. These findings suggest that inhibition of an impending motor action can be initiated by an unconscious stimulus.
Mechanism of docosahexaenoic acid‐induced inhibition of in vitro Aβ1–42 fibrillation and Aβ1–42‐induced toxicity in SH‐S5Y5 cells
Authors: Hossain Shahdat , Hashimoto Michio , Katakura Masanori , Miwa Koji , Shimada Toshio , Shido Osamu
Published: August 2009

The mechanism of the effect of docosahexaenoic acid (DHA; C22:6, n‐3), one of the essential brain nutrients, on in vitro fibrillation of amyloid β (Aβ1–42), Aβ1–42‐oligomers and its toxicity imparted to SH‐S5Y5 cells was studied with the use of thioflavin T fluorospectroscopy, laser confocal microfluorescence, and transmission electron microscopy. The results clearly indicated that DHA inhibited Aβ1–42‐fibrill formation with a concomitant reduction in the levels of soluble Aβ1–42 oligomers. The polymerization (into fibrils) of preformed oligomers treated with DHA was inhibited, indicating that DHA not only obstructs their formation but also inhibits their transformation into fibrils. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (12.5%), Tris–Tricine gradient(4–20%) gel electrophoresis and western blot analyses revealed that DHA inhibited at least 2 species of Aβ1–42 oligomers of 15–20 kDa, indicating that it hinders these on‐pathway tri/tetrameric intermediates during fibrillation. DHA also reduced the levels of dityrosine and tyrosine intrinsic fluorescence intensity, indicating DHA interrupts the microenvironment of tyrosine in the Aβ1–42 backbone. Furthermore, DHA protected the tyrosine from acrylamide collisional quenching, as indicated by decreases in Stern–Volmer constants. 3‐[4,5‐Dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide‐reduction efficiency and immunohistochemical examination suggested that DHA inhibits Aβ1–42‐induced toxicity in SH‐S5Y5 cells. Taken together, these data suggest that by restraining Aβ1–42 toxic tri/tetrameric oligomers, DHA may limit amyloidogenic neurodegenerative diseases, Alzheimer’s disease.
Sialidase occurs in both membranes of the nuclear envelope and hydrolyzes endogenous GD1a
Authors: Wang Jianfeng , Wu Gusheng , Miyagi Taeko , Lu Zi‐Hua , Ledeen Robert W.
Published: August 2009

Previous reports indicated the presence of both gangliosides and sialidase in the nuclear envelope (NE) of primary neurons and the NG108‐15 neural cell line. GM1, one of the major gangliosides of this membrane, was shown to be tightly associated with a sodium‐calcium exchanger in the inner membrane of the NE and to potentiate exchanger activity. GD1a was the other major ganglioside detected in the NE and, like GM1, occurs in both inner and outer membranes. A subsequent report indicated the presence of sialidase activity in the NE without specification as to which of the two membranes express it. The present study was undertaken to determine the nature and locus of this activity within the NE of two cell lines: NG108‐15 and SH‐SY5Y. Western blot analysis of the separated membranes revealed occurrence of Neu3 in the inner membrane and Neu1 in the outer membrane of the NE. Moreover, sialidase activity at both sites was shown capable of catalyzing conversion of endogenous GD1a to GM1.
Optimization of continuous in vivo DOPA production and studies on ectopic DA synthesis using rAAV5 vectors in Parkinsonian rats
Authors: Björklund Tomas , Hall Hélène , Breysse Nathalie , Soneson Charlotte , Carlsson Thomas , Mandel Ronald J. , Carta Manolo , Kirik Deniz
Published: August 2009

Viral vector‐mediated gene transfer is emerging as a novel therapeutic approach with clinical utility in treatment of Parkinson’s disease. Recombinant adeno‐associated viral (rAAV) vector in particular has been utilized for continuous l‐3,4 dihydroxyphenylalanine (DOPA) delivery by expressing the tyrosine hydroxylase (TH) and GTP cyclohydrolase 1 (GCH1) genes which are necessary and sufficient for efficient synthesis of DOPA from dietary tyrosine. The present study was designed to determine the optimal stoichiometric relationship between TH and GCH1 genes for ectopic DOPA production and the cellular machinery involved in its synthesis, storage, and metabolism. For this purpose, we injected a fixed amount of rAAV5‐TH vector and increasing amounts of rAAV5‐GCH1 into the striatum of rats with complete unilateral dopamine lesion. After 7 weeks the animals were killed for either biochemical or histological analysis. We show that increasing the availability of 5,6,7,8‐tetrahydro‐l‐biopterin (BH4) in the same cellular compartment as the TH enzyme resulted in better efficiency in DOPA synthesis, most likely by hindering inactivation of the enzyme and increasing its stability. Importantly, the BH4 synthesis from ectopic GCH1 expression was saturable, yielding optimal TH enzyme functionality between GCH1 : TH ratios of 1 : 3 and 1 : 7.
Brain‐derived neurotrophic factor facilitates TrkB down‐regulation and neuronal injury after status epilepticus in the rat hippocampus
Authors: Unsain Nicolás , Montroull Laura Ester , Mascó Daniel Hugo
Published: August 2009

Brain‐derived neurotrophic factor (BDNF) is involved in many aspects of neuronal biology and hippocampal physiology. Status epilepticus (SE) is a condition in which prolonged seizures lead to neuronal degeneration. SE‐induced in rodents serves as a model of Temporal Lobe Epilepsy with hippocampal sclerosis, the most frequent epilepsy in humans. We have recently described a strong correlation between TrkB decrease and p75ntr increase with neuronal degeneration (Neuroscience 154:978, 2008). In this report, we report that local, acute intra‐hippocampal infusion of function‐blocking antibodies against BDNF prevented both early TrkB down‐regulation and neuronal degeneration after SE. Conversely, the infusion of recombinant human BDNF protein after SE greatly increased neuronal degeneration. The inhibition of BDNF mRNA translation by the infusion of antisense oligonucleotides induced a rapid decrease of BDNF protein levels, and a delayed increase. If seizures were induced at the time endogenous BDNF was decreased, SE‐induced neuronal damage was prevented. On the other hand, if seizures were induced at the time endogenous BDNF was increased, SE‐induced neuronal damage was exacerbated. These results indicate that under a pathological condition BDNF exacerbates neuronal injury.
Opposite effect of membrane raft perturbation on transport activity of KCC2 and NKCC1
Authors: Hartmann Anna‐Maria , Blaesse Peter , Kranz Thorsten , Wenz Meike , Schindler Jens , Kaila Kai , Friauf Eckhard , Nothwang Hans Gerd
Published: August 2009

In the majority of neurons, the intracellular Cl− concentration is set by the activity of the Na+‐K+‐2Cl− cotransporter (NKCC1) and the K+‐Cl− cotransporter (KCC2). Here, we investigated the cotransporters’ functional dependence on membrane rafts. In the mature rat brain, NKCC1 was mainly insoluble in Brij 58 and co‐distributed with the membrane raft marker flotillin‐1 in sucrose density flotation experiments. In contrast, KCC2 was found in the insoluble fraction as well as in the soluble fraction, where it co‐distributed with the non‐raft marker transferrin receptor. Both KCC2 populations displayed a mature glycosylation pattern. Disrupting membrane rafts with methyl‐β‐cyclodextrin (MβCD) increased the solubility of KCC2, yet had no effect on NKCC1. In human embryonic kidney‐293 cells, KCC2 was strongly activated by a combined treatment with MβCD and sphingomyelinase, while NKCC1 was inhibited. These data indicate that membrane rafts render KCC2 inactive and NKCC1 active. In agreement with this, inactive KCC2 of the perinatal rat brainstem largely partitioned into membrane rafts. In addition, the exposure of the transporters to MβCD and sphingomyelinase showed that the two transporters differentially interact with the membrane rafts. Taken together, membrane raft association appears to represent a mechanism for co‐ordinated regulation of chloride transporter function.
Selecting healthy volunteers in specific populations: a retrospective analysis of clinical and laboratory screening
Authors: Roux Clarisse , Chevassus Hugues , Farret Anne , Costa Françoise , Petit Pierre , Galtier Florence
Published: August 2009

Healthy volunteers must undergo a medical examination before enrolment in a clinical trial. An increasing number of trials include specific populations designed to match the target populations of the drugs tested. Our study aimed at evaluating which investigations are the most appropriate in different sub‐populations of healthy volunteers. Data from 350 healthy volunteers who attended our Research Center from 1997 to 2004 were retrospectively analysed. Volunteers were distributed into five sub‐populations: young men, senior men, overweight men, young women, postmenopausal women. The screening procedure comprised a review of medical history, physical examination, electrocardiogram and laboratory tests. Ineligibility criteria were classified as non‐medical causes, protocol specific medical causes and non‐specific medical causes. A total of 148 subjects (42%) were not‐eligible, mainly because of non‐specific medical causes (111 subjects), including abnormal medical history (34.5% of all ineligibilities). Blood pressure abnormalities were frequent in all sub‐populations except young women. Electrocardiographic abnormalities led to ineligibility of only five overweight men and one menopausal woman. Abnormal laboratory tests accounted for 19.6% of ineligibilities. In senior subjects and overweight men, serologies, liver function tests and lipid profile contributed importantly to the selection process. Low red cells count was the most frequent laboratory abnormality in young women. Erythrocyte sedimentation rate, phosphocalcic metabolism and standard clotting tests led to frequent insignificant and non‐contributive abnormalities. Our study confirms that a complete review of medical history is essential and determines the major part of ineligibilities. Complementary laboratory tests are always needed and may be adjusted to the population considered.
Agency Discretion and Public Health Service Delivery
Authors: McCann Pamela J. Clouser
Published: August 2009

Objective. To study how changes in law shape the public health system.

Data Sources. State newborn screening laws and the National Newborn Screening and Genetics Resource Center (NNSGRC).

Study Design. A time‐series, quasi‐experimental design spanning the years 1990–2006 for all states and the District of Columbia was conducted. Analysis proceeded using a multinomial logit with a dependent variable of whether agencies lagged behind, were on target with, or led their newborn screening law. Explanatory variables of three different types of limitations on agency discretion plus relevant controls were included in the model.

Data Collection. State laws were coded for three types of discretion: whether an agency can choose a state's newborn screening panel conditions, whether an agency can charge and change newborn screening fees, and whether the agency can define their own newborn screening criteria. Each state's newborn screening law for each year in the dataset was coded with respect to the mandated number of conditions on a panel and compared with the NNSGRC dataset of actual newborn screening implemented in the state.

Principal Findings. States that lack condition discretion have 6.02 greater odds of lagging behind newborn screening law, but the presence of criteria discretion results in 7.50 higher odds of lagging behind the law. Condition discretion and fiscal discretion are associated with successful implementation. The presence of criteria discretion is a barrier for successful implementation.

Conclusions. Agency discretion can both hinder and facilitate program implementation. Thus, type of discretion determines implementation.
A Framework to Measure the Value of Public Health Services
Authors: Jacobson Peter D. , Neumann Peter J.
Published: August 2009

Objective. To develop a framework that public health practitioners could use to measure the value of public health services.

Data Sources. Primary data were collected from August 2006 through March 2007. We interviewed (n=46) public health practitioners in four states, leaders of national public health organizations, and academic researchers.

Study Design. Using a semi‐structured interview protocol, we conducted a series of qualitative interviews to define the component parts of value for public health services and identify methodologies used to measure value and data collected.

Data Collection/Extraction Methods. The primary form of analysis is descriptive, synthesizing information across respondents as to how they measure the value of their services.

Principal Findings. Our interviews did not reveal a consensus on how to measure value or a specific framework for doing so. Nonetheless, the interviews identified some potential strategies, such as cost accounting and performance‐based contracting mechanisms. The interviews noted implementation barriers, including limits to staff capacity and data availability.

Conclusions. We developed a framework that considers four component elements to measure value: external factors that must be taken into account (i.e., mandates); key internal actions that a local health department must take (i.e., staff assessment); using appropriate quantitative measures; and communicating value to elected officials and the public.
Geographic Variation in Public Health Spending: Correlates and Consequences
Authors: Mays Glen P. , Smith Sharla A.
Published: August 2009

Objectives. To examine the extent of variation in public health agency spending levels across communities and over time, and to identify institutional and community correlates of this variation.

Data Sources and Setting. Three cross‐sectional surveys of the nation's 2,900 local public health agencies conducted by the National Association of County and City Health Officials in 1993, 1997, and 2005, linked with contemporaneous information on population demographics, socioeconomic characteristics, and health resources.

Study Design. A longitudinal cohort design was used to analyze community‐level variation and change in per‐capita public health agency spending between 1993 and 2005. Multivariate regression models for panel data were used to estimate associations between spending, institutional characteristics, health resources, and population characteristics.

Principal Findings. The top 20 percent of communities had public health agency spending levels >13 times higher than communities in the lowest quintile, and most of this variation persisted after adjusting for differences in demographics and service mix. Local boards of health and decentralized state‐local administrative structures were associated with higher spending levels and lower risks of spending reductions. Local public health agency spending was inversely associated with local‐area medical spending.

Conclusions. The mechanisms that determine funding flows to local agencies may place some communities at a disadvantage in securing resources for public health activities.
Elimination of an Artificial Immune Complex by Plasmapheresis in Rabbits
Authors: Bambauer R. , Dahlem R. , Gössel L. , Biro G. , Inniger R. , Schmer G.
Published: August 2009

Abstract: The behavior of an artificial immune complex was investigated in 15 rabbits. The immune complex was labeled with iodine‐125 (125I). The advantage was that the immune complex could not be metabolized without being eliminated by the kidney. This artificial immune complex was injected in a dosage of 0.8 pg, in 2 rabbits, 5.0 μg in 4 rabbits, 10 μg in 3 rabbits, 20 μg in 2 rabbits, and 40 μg in 4 rabbits on two consecutive days. One group (n = 9) was treated with plasmapheresis: the other (n = 6) was a control group that did not undergo plasmapheresis. A miniaturized plasmapheresis system eliminated the immune complex very effectively with an average exchange volume of 95.7 ml per treatment. The increasing concentration of the immune complex in the blood before the next plasmapheresis treatment was probably an expression of mobilization of the immune complex from different organs. The animals of the plasmapheresis group were in better condition than the control group.
Plasmapheresis in Newborns with Hyperbilirubinemia
Authors: Bambauer R. , El‐Saadi R. , Graf N. , Jesberger H.J. , Limbach H.G. , Cordes H.
Published: August 2009

Abstract: With a miniaturized plasmapheresis system consisting of a double head pump and balancing pump, extracorporeal detoxification treatments such as plasmapheresis, hemofiltration, and hernodialysis were carried out. In total 15 premature infants and newborns with Rh‐erythroblastosis and hyperbilirubinemia were treated using this miniaturized system. The average birth weight of the 15 patients was 2,386 g. With a main blood flow of 5.3 ml/min and a filtrate flow of 1.3 ml/min, an average of 192.4 ml of plasma per treatment was exchanged. In all patients 1 to 10 plasmapheresis treatments were necessary to reduce the mean serum bilirubin from 15.6 ‡ 4.8 to 7.3 ‡ 3.2 mg/dl, and after several days the serum bilirubin subsequently normalized in 12 patients, who improved. Three patients died 5 to 18 days after birth as a result of their primary disease and immaturity. For vascular access small catheters were inserted in the umbilical or the femoral vein. All treatments were well tolerated by the patients.
Effects of Synchronous Pulsatile Extracorporeal Membrane Oxygenation in an Endotoxin‐Induced Shock Model: An Experimental Study
Authors: Okuyama Hiroomi , Kamata Shinkichi , Ishikawa Shirou , Usui Noriaki , Okada Akira , Yamatodani Atsusi
Published: August 2009

Abstract: A synchronous pulsatile venoarterial device for extracorporeal membrane oxygenation (ECMO) was designed to accomplish more effective circulatory support for neonates. The effect of this device was studied using an endotoxin‐induced shock model, compared with conventional nonpulsatile ECMO. Twenty puppies weighing 1.6 to 4.0 kg were given endotoxin (5 mg/kg) intravenously. Thirty minutes after the administration of endotoxin, 10 were placed on pulsatile ECMO, and the others were placed on nonpulsatile ECMO, and they were studied for an additional 180 min. Peak blood pressure, arterial pH, base excess, and renal blood flow were significantly higher in the pulsatile group than in the nonpulsatile group. Serum lactate and serum noradrenaline were significantly lower in the pulsatile group than in the nonpulsatile group. These results indicate that pulsatile ECMO may provide more effective cardiopulmonary support in the treatment of neonates with serious circulatory failure that has failed to be supported by nonpulsatile ECMO.