bluuebunny/crossref_metadata_2025 huggingface dataset:
Extracellular guanosine and GTP promote expression of differentiation markers and induce S‐phase cell‐cycle arrest in human SH‐SY5Y neuroblastoma cells
Authors: Guarnieri S. , Pilla R. , Morabito C. , Sacchetti S. , Mancinelli R. , Fanò G. , Mariggiò M.A.
Published: December 2008

SH‐SY5Y neuroblastoma cells, a model for studying neuronal differentiation, are able to differentiate into either cholinergic or dopaminergic/adrenergic phenotypes depending on media conditions. Using this system, we asked whether guanosine (Guo) or guanosine‐5′‐triphosphate (GTP) are able to drive differentiation towards one particular phenotype. Differentiation was determined by evaluating the frequency of cells bearing neurites and assessing neurite length after exposure to different concentrations of Guo or GTP for different durations. After 6 days, 0.3 mM Guo or GTP induced a significant increase in the number of cells bearing neurites and increased neurite length. Western blot analyses confirmed that purines induced differentiation; cells exposed to purines showed increases in the levels of GAP43, MAP2, and tyrosine hydroxylase. Proliferation assays and cytofluorimetric analyses indicated a significant anti‐proliferative effect of purines, and a concentration‐dependent accumulation of cells in S‐phase, starting after 24 h of purine exposure and extending for up to 6 days. A transcriptional profile analysis using gene arrays showed that an up‐regulation of cyclin E2/cdk2 evident after 24 h was responsible for S‐phase entry, and a concurrent down‐regulation of cell‐cycle progression‐promoting cyclin B1/B2 prevented S‐phase exit. In addition, patch‐clamp recordings revealed that 0.3 mM Guo or GTP, after 6 day incubation, significantly decreased Na+ currents.

In conclusion, we showed Guo‐ and GTP‐induced cell‐cycle arrest in neuroblastoma cells and suggest that this makes these cells more responsive to differentiation processes that favor the dopaminergic/adrenergic phenotype.
Intrarater and Interrater Reliability of the Balance Error Scoring System (BESS)
Authors: Finnoff Jonathan T. , Peterson Valerie J. , Hollman John H. , Smith Jay
Published: December 2008

Objective

The purpose of this study was to determine the intrarater and interrater reliability of the Balance Error Scoring System (BESS).

Design

A prospective observational study.

Setting

Academic sports medicine center.

Participants

Three scorers participated in this study.

Methods

Three scorers experienced in using the BESS viewed a videotape depicting 30 consecutive individuals performing the BESS stance positions. The 3 scorers independently scored each of the 30 videotaped individuals using the BESS scoring criteria. A week later, the same 3 subjects viewed and scored the videotape again.

Main Outcome Measurements

The interrater and intrarater reliability of the BESS was determined using intraclass correlation coefficients (ICC), reported with 95% confidence intervals. The minimum detectible change was also determined.

Results

The interrater and intrarater reliability ICCs for the total BESS scores were 0.57 and 0.74, respectively. The interrater reliability ICCs for the 6 different stance positions were between 0.44 and 0.83, while the intrarater reliability ICCs were between 0.50 and 0.88. The interrater and intrarater minimum detectible change for the total BESS score were 9.4 and 7.3 points, respectively.

Conclusion

This study suggests that certain subcategories of the BESS have sufficient reliability to be used in the evaluation of postural stability but that the total BESS score is not reliable. In addition, a change in score of greater than 9.4 (interrater) or 7.3 (intrarater) points is required before the change in postural stability can be attributed to the balancer rather than to the scorer.
Marketization and China's energy security
Authors: Chen Shaofeng
Published: December 2008

Marketization of the petroleum industry is part of China's efforts to construct a market economy. This has provided strong incentives for national oil companies (NOCs) to seek their commercial interests. Nevertheless, marketization of this industry is only partial. What impact does the partial marketization have on China's energy security against the backdrop of its growing reliance on foreign energy resources? This paper argues that China is plagued by two paradoxes when dealing with its energy security problems: between state centralism and market domination, as well as between state control and NOCs’ struggle for greater autonomy. Both paradoxes stem from the government's distrust of the market and the multi-faceted goals that it has set for the petroleum industry. The government's high expectation of the NOCs enhancing China's energy security with their oligarchic monopoly rights could prove to be a little far-fetched.
The effect of drainage on the capillary retention of CO2 in a layered permeable rock
Authors: FARCAS ADRIAN , WOODS ANDREW W.
Published: December 2008

Buoyant plumes of CO2 spreading through water-saturated permeable rock, bounded by layers of lower permeability, tend to spread laterally. As they advance, they may gradually leak through fractures or discontinuities in the lower permeability boundary, leading to a gradual waning of the original plume and dispersal of CO2 higher in the formation. With a finite release of CO2, the trailing edge of the plume recedes with time, and capillary forces tend to trap a fraction of this CO2 within the pore space. This also leads to a gradual waning of the plume with time and limits the mass of CO2 which can leak through the boundary and rise higher into the formation. We explore the balance between these two effects and calculate some of the controls on the fraction of the CO2 plume which becomes trapped within the original layer of rock.
Hydraulic jumps in a channel
Authors: BONN DANIEL , ANDERSEN ANDERS , BOHR TOMAS
Published: December 2008

We present a study of hydraulic jumps with flow predominantly in one direction, created either by confining the flow to a narrow channel with parallel walls or by providing an inflow in the form of a narrow sheet. In the channel flow, we find a linear height profile upstream of the jump as expected for a supercritical one-dimensional boundary layer flow, but we find that the surface slope is up to an order of magnitude larger than expected and independent of flow rate. We explain this as an effect of turbulent fluctuations creating an enhanced eddy viscosity, and we model the results in terms of Prandtl's mixing-length theory with a mixing length that is proportional to the height of the fluid layer. Using averaged boundary-layer equations, taking into account the friction with the channel walls and the eddy viscosity, the flow both upstream and downstream of the jump can be understood. For the downstream subcritical flow, we assume that the critical height is attained close to the channel outlet. We use mass and momentum conservation to determine the position of the jump and obtain an estimate which is in rough agreement with our experiment. We show that the averaging method with a varying velocity profile allows for computation of the flow-structure through the jump and predicts a separation vortex behind the jump, something which is not clearly seen experimentally, probably owing to turbulence. In the sheet flow, we find that the jump has the shape of a rhombus with sharply defined oblique shocks. The experiment shows that the variation of the opening angle of the rhombus with flow rate is determined by the condition that the normal velocity at the jump is constant.
Linear superposition of nonlinear waves
Authors: MAHAJAN SWADESH , MIURA HIDEAKI
Published: December 2008

Exact nonlinear (arbitrary amplitude) wave-like solutions of an incompressible, magnetized, non-dissipative two-fluid system are found. It is shown that, in 1-D propagation, these fully nonlinear solutions display a rare property; they can be linearly superposed.
Mood lability and psychopathology in youth
Authors: Stringaris A. , Goodman R.
Published: December 2008

Background

Mood lability is a concept widely used. However, data on its prevalence and morbid associations are scarce. We sought to establish the occurrence and importance of mood lability in a large community sample of children and adolescents by testing a priori hypotheses.

Method

Cross-sectional data were taken from a national mental health survey including 5326 subjects aged 8–19 years in the UK. The outcomes were prevalence and characteristics of mood lability and its associations with psychopathology and overall impairment.

Results

Mood lability occurred in more than 5% of the population of children and adolescents, both by parent and self-report. Mood lability was strongly associated with a wide range of psychopathology and was linked to significant impairment even in the absence of psychiatric disorders. Mood lability was particularly strongly associated with co-morbidity between internalizing and externalizing disorders, even when adjusting for the association with individual disorders. The pattern of results did not change after excluding youth with bipolar disorder or with episodes of elated mood.

Conclusions

Clinically significant mood lability is relatively common in the community. Our findings indicate that mood lability is not a mere consequence of other psychopathology in that it is associated with significant impairment even in the absence of psychiatric diagnoses. Moreover, the pattern of association of mood lability with co-morbidity suggests that it could be a risk factor shared by both internalizing and externalizing disorders. Our data point to the need for greater awareness of mood lability and its implications for treatment.
Look Ma, no fingers! Are children numerical solipsists?
Authors: Gordon Peter
Published: December 2008

I ask whether it is necessary that principles of number be mentally represented and point to the role of language in determining cultural variation. Some cultures possess extensive counting systems that are finite. I suggest that learning number principles is similar to learning conservation and, as such, might be derived from learning about the empirical properties of objects and other individuals in combinations.
The origins of number: Getting developmental
Authors: Mix Kelly S.
Published: December 2008

Rips et al. raise important questions about the relation between infant quantification and achievement of natural number concepts. However, they may be oversimplifying the interactions that characterize actual development in real time. Though they propose a worthwhile agenda for future research, its explanatory power will be limited if it does not address developmental issues with greater sensitivity.
The innate schema of natural numbers does not explain historical, cultural, and developmental differences
Authors: Noël Marie-Pascale , Grégoire Jacques , Meert Gaëlle , Seron Xavier
Published: December 2008

Rips et al.'s proposition cannot account for the facts that (1) a historical look at the word number systems suggests that the concept of natural numbers has been progressively elaborated; (2) people from cultures without an elaborate counting system do not master the concept of natural numbers; (3) children take time to master natural numbers; and (4) the competing advantage of the postulated math schema in the natural selection process is not obvious.
Natural number concepts: No derivation without formalization
Authors: Pietroski Paul , Lidz Jeffrey
Published: December 2008

The conceptual building blocks suggested by developmental psychologists may yet play a role in how the human learner arrives at an understanding of natural number. The proposal of Rips et al. faces a challenge, yet to be met, faced by all developmental proposals: to describe the logical space in which learners ever acquire new concepts.
Semantic cognition: Distributed, but then attractive
Authors: Kropff Emilio , Treves Alessandro
Published: December 2008

The parallel distributed processing (PDP) perspective brings forward the important point that all semantic phenomena are based on analog underlying mechanisms, involving the weighted summation of multiple inputs by individual neurons. It falls short of indicating, however, how the essentially discrete nature of semantic processing may emerge at the cognitive level. Bridging this gap probably requires attractor networks.
Some suggested additions to the semantic cognition model
Authors: Mandler Jean M.
Published: December 2008

Rogers & McClelland (R&M) present a powerful account of semantic (conceptual) learning. Their model admirably handles many characteristics of early concept formation, but it also needs to address attentional biases, and distinguish direct input from error-driven learning, and fast versus slow learning. Not distinguishing implicit and explicit knowledge means that the authors also cannot explain why some coherently varying information becomes accessible and other information does not.
Concepts, correlations, and some challenges for connectionist cognition
Authors: Marcus Gary F. , Keil Frank C.
Published: December 2008

Rogers & McClelland's (R&M's) précis represents an important effort to address key issues in concepts and categorization, but few of the simulations deliver what is promised. We argue that the models are seriously underconstrained, importantly incomplete, and psychologically implausible; more broadly, R&M dwell too heavily on the apparent successes without comparable concern for limitations already noted in the literature.
Investigation of clear‐sky occurrence rate estimated from CALIOP and MODIS observations
Authors: Eguchi Nawo , Yokota Tatsuya
Published: December 2008

We derived the global distribution of the clear‐sky occurrence rate during the daytime using Cloud‐Aerosol Lidar with Orthogonal Polarization (CALIOP) and Moderate‐resolution Imaging Spectrometer (MODIS) data. Our goal was to estimate the frequency of likely successful CO2 and CH4 column concentration retrievals by the Greenhouse gases Observing Satellite (GOSAT). Clear‐sky regions over land were frequently found around desert regions throughout the year, and at northern mid‐latitudes in the winter hemisphere. Overall, clear‐sky regions covered approximately 11% of the globe annually, on average. From a comparison of the CALIOP and MODIS cloud data for June 2007, we found that MODIS overestimated the clear‐sky ratio by approximately 5%, except for in the tropics.
Implications of particle composition and shape to dust radiative effect: A case study from the Great Indian Desert
Authors: Mishra S. K. , Dey Sagnik , Tripathi S. N.
Published: December 2008

The assessment of direct radiative forcing (DRF) of aerosol is uncertain, particularly where the natural dust particles mix with the anthropogenic components. One of the sources of such uncertainty is the assumption of morphology (size and shape) and composition of pure dust particles. Recently Mishra and Tripathi [2008] have computationally assessed the effect of particle morphology on optical properties over the Great Indian Desert. As a continuation of the previous study, in this paper, we have further examined the effects on dust radiative properties. Non‐spherical pure dust particles show large variations in the optical and radiative properties from spherical pure dust particles, however, particle composition is found to have greater influence than particle shape on the radiative properties. Among the various shapes, sharp‐edged particles show larger difference than smooth‐shaped particles. Although the overall atmospheric absorption monotonically increases with increase in hematite content, maximum effect of particle non‐sphericity at 4% hematite content implies that non‐sphericity should be considered to minimize the uncertainty of regional estimates of aerosol DRF, as most of the global dusts contain that much hematite. However the difference in radiative properties for two different background dust cases due to particle morphology is low. Our results show that ignoring non‐sphericity will lead to under‐estimation of the regional warming and dust‐absorption efficiency.
Persistent elastic behavior above a megathrust rupture patch: Nias island, West Sumatra
Authors: Briggs Richard W. , Sieh Kerry , Amidon William H. , Galetzka John , Prayudi Dudi , Suprihanto Imam , Sastra Nugraha , Suwargadi Bambang , Natawidjaja Danny , Farr Thomas G.
Published: December 2008

We quantify fore‐arc deformation using fossil reefs to test the assumption commonly made in seismic cycle models that anelastic deformation of the fore arc is negligible. Elevated coral microatolls, paleoreef flats, and chenier plains show that the Sumatran outer arc island of Nias has experienced a complex pattern of relatively slow long‐term uplift and subsidence during the Holocene epoch. This same island rose up to 2.9 m during the Mw 8.7 Sunda megathrust rupture in 2005. The mismatch between the 2005 and Holocene uplift patterns, along with the overall low rates of Holocene deformation, reflects the dominance of elastic strain accumulation and release along this section of the Sunda outer arc high and the relatively subordinate role of upper plate deformation in accommodating long‐term plate convergence. The fraction of 2005 uplift that will be retained permanently is generally <4% for sites that experienced more than 0.25 m of coseismic uplift. Average uplift rates since the mid‐Holocene range from 1.5 to −0.2 mm/a and are highest on the eastern coast of Nias, where coseismic uplift was nearly zero in 2005. The pattern of long‐term uplift and subsidence is consistent with slow deformation of Nias along closely spaced folds in the north and trenchward dipping back thrusts in the southeast. Low Holocene tectonic uplift rates provide for excellent geomorphic and stratigraphic preservation of the mid‐Holocene relative sea level high, which was under way by ∼7.3 ka and persisted until ∼2 ka.
Taxonomy and phylogeny of the Hister servus group (Coleoptera: Histeridae): a Neotropical radiation
Authors: Caterino Michael S.
Published: December 2008

The Hister servus group contains ten species and two species complexes. Although the group’s diversity is centred in Mexico and Central America, one lineage, comprising H. indistinctus Say, H. defectus LeConte and H. fungicola Schaeffer, has probably diversified entirely in the south‐eastern U.S. The servus group also contains the following species: H. servusErichson, H. nodatuslewis, H. doyeni sp.n., H. lagoi sp.n., H. bullatuslewis, H. coronatus Marseul and H. diadema Marseul and two diverse species complexes, dubbed the comes complex and the montivagus complex. These two complexes require additional sampling and study before species within them can be recognized. They are, however, closely related to each other and appear to be paraphyletic with respect to a clade comprising H. bullatus, H. coronatus and H. diadema. A prior hypothesis that the servus group includes H. sallei, H. matador sp.n. and the species of Hister (Spilodiscus) is not well supported. Several sister groups within the servus group show geographical disjunction between seasonal tropical habitats of western North America and wetter montane habitats of the eastern parts of the continent along the Gulf and Caribbean coasts.
Susceptibility in subcritical random graphs
Authors: Janson Svante , Luczak Malwina J.
Published: December 2008

We study the evolution of the susceptibility in the subcritical random graph G(n,p) as n tends to infinity. We obtain precise asymptotics of its expectation and variance and show that it obeys a law of large numbers. We also prove that the scaled fluctuations of the susceptibility around its deterministic limit converge to a Gaussian law. We further extend our results to higher moments of the component size of a random vertex and prove that they are jointly asymptotically normal.
Ferroelectric devices created by pressure modulated stencil deposition
Authors: te Riele Paul M. , Rijnders Guus , Blank Dave H. A.
Published: December 2008

Ferroelectric Pb(ZrxTi1−x)O3 sandwiched between SrRuO3 electrodes devices were fabricated by a single stencil deposition method. By varying the pressure, the dimension of the deposited pattern could be controlled. The dimension becomes larger in the high pressure shockwave regime, which is typical for pulsed laser deposition. The particle interactions result in an increased amount of broadening. At lower pressures, the deposited material is still in the correct crystalline phase and broadening is minimized. Top electrodes are isolated from the bottom electrode by controlling the broadening of the ferroelectric medium. With this method, multilayered oxide devices can be created in situ.
Conformable coating of SiO2 on hydrothermally grown ZnO nanorods
Authors: Chu B. H. , Leu L. C. , Chang C. Y. , Lugo F. , Norton D. , Lele T. , Keselowsky B. , Pearton S. J. , Ren F.
Published: December 2008

Coating silicon dioxide on hydrothermally grown ZnO nanorods is demonstrated using a low temperature plasma enhanced chemical vapor deposition (PECVD) system. Wurtzite structured ZnO nanorods were prepared by spin coating ZnO nanocrystals onto plastics or glass substrates. Then, the nanorods were subsequently grown in a zinc nitrate solution. SiO2 was deposited by PECVD at 50 °C. No current could be measured through the patterned metal dots on the SiO2 coated sample, which indicates that SiO2 was covered seamlessly across the entire substrate. Photoluminescence measurements indicated that the SiO2 layer covering the nanorods did not alter the optical properties of the ZnO.
Plasma-chemical processes in microwave plasma-enhanced chemical vapor deposition reactors operating with C/H/Ar gas mixtures
Authors: Mankelevich Yuri A. , Ashfold Michael N. R. , Ma Jie
Published: December 2008

Microwave (MW) plasma-enhanced chemical vapor deposition (PECVD) reactors are widely used for growing diamond films with grain sizes spanning the range from nanometers through microns to millimeters. This paper presents a detailed description of a two-dimensional model of the plasma-chemical activation, transport, and deposition processes occurring in MW activated H/C/Ar mixtures, focusing particularly on the following base conditions: 4.4%CH4/7%Ar/balance H2, pressure p=150 Torr, and input power P=1.5 kW. The model results are verified and compared with a range of complementary experimental data in the companion papers. These comparators include measured (by cavity ring down spectroscopy) C2(a), CH(X), and H(n=2) column densities and C2(a) rotational temperatures, and infrared (quantum cascade laser) measurements of C2H2 and CH4 column densities under a wide range of process conditions. The model allows identification of spatially distinct regions within the reactor that support net CH4→C2H2 and C2H2→CH4 conversions, and provide a detailed mechanistic picture of the plasma-chemical transformations occurring both in the hot plasma and in the outer regions. Semianalytical expressions for estimating relative concentrations of the various C1Hx species under typical MW PECVD conditions are presented, which support the consensus view regarding the dominant role of CH3 radicals in diamond growth under such conditions.
Non-Markovian suppression of charge qubit decoherence in the quantum point contact measurement
Authors: Lee Ming-Tsung , Zhang Wei-Min
Published: December 2008

A nonequilibrium theory describing the charge qubit dynamics measured by a quantum point contact is developed based on Schwinger–Keldysh’s approach. Using the real-time diagrammatic technique, we derive the master equation to all orders in perturbation expansions. The non-Markovian processes in the qubit dynamics is naturally taken into account. The qubit decoherence, in particular, the influence of the tunneling-electron fluctuation in the quantum point contact with a longer correlation time comparing to the time scale of the qubit dynamics, is studied in the framework. We consider the Lorentzian-type spectral density to characterize the channel mixture of the electron-tunneling processes induced by the measurement, and determine the correlation time scale of the tunneling-electron fluctuation. The result shows that as the quantum point contact is casted with a narrower profile of the spectral density, tunneling electrons propagate in a longer correlation time scale and lead to the non-Markovian processes of the qubit dynamics. The qubit electron in the charge qubit can be driven coherently. The quantum point contact measurement with the minimum deviation of the electron-tunneling processes prevents the qubit state from the decoherence.
Absence of elastic clamping in quantitative piezoelectric force microscopy measurements of nanostructures
Authors: Scrymgeour David A. , Hsu Julia W. P.
Published: December 2008

We establish that clamping effects, which limit accurate determination of piezoelectric responses in bulk materials and films using piezoelectric force microscopy (PFM), are not present when measuring discrete nanostructures with radii less than five times the tip radius. This conclusion is established by comparing the piezoelectric response in ZnO rods using two electrode configurations: one with the conducting atomic force microscopy tip acting as the top electrode and the other using a uniform metal top electrode. The distributions of piezoelectric coefficients measured with these two types of electrode configurations are the same. Hence, clamping issues do not play a role in the piezoelectric property measurement of nanomaterials using PFM. The role of conduction electrons on the piezoelectric measurement in both cases is also discussed.
A nanotube based electron microbeam cellular irradiator for radiobiology research
Authors: Bordelon David E. , Zhang Jian , Graboski Sarah , Cox Adrienne , Schreiber Eric , Zhou Otto Z. , Chang Sha
Published: December 2008

A prototype cellular irradiator utilizing a carbon nanotube (CNT) based field emission electron source has been developed for microscopic image-guided cellular region irradiation. The CNT cellular irradiation system has shown great potential to be a high temporal and spatial resolution research tool to enable researchers to gain a better understanding of the intricate cellular and intercellular microprocesses occurring following radiation deposition, which is essential to improving radiotherapy cancer treatment outcomes. In this paper, initial results of the system development are reported. The relationship between field emission current, the dose rate, and the dose distribution has been investigated. A beam size of 23 μm has been achieved with variable dose rates of 1–100 Gy/s, and the system dosimetry has been measured using a radiochromic film. Cell irradiation has been demonstrated by the visualization of H2AX phosphorylation at DNA double-strand break sites following irradiation in a rat fibroblast cell monolayer. The prototype single beam cellular irradiator is a preliminary step to a multipixel cell irradiator that is under development.
Thermal sintering of solution-deposited nanoparticle silver ink films characterized by spectroscopic ellipsometry
Authors: Pan Heng , Ko Seung H. , Grigoropoulos Costas P.
Published: December 2008

Low-temperature sintering of metal nanoparticle inks is a promising technique in realizing large area and flexible electronics. It is demonstrated in this letter that spectroscopic ellipsometry in the spectral region of 0.75–3.5 eV can be employed to characterize the sintering process manifested by the evolution of film thickness, effective dielectric function, and percolation transition. A two-oscillator model can be used to model the effective dielectric function. The oscillator energy shifts lower and correlates well with the increase in dc conductance as demonstrated by both in situ and ex situ ellipsometric measurements. A simple model based on two-dimensional R-L-C impedance network was adopted to explain experimental results quantitatively.
Reversible photoswitching behavior in bulk resistance and in color of polycrystalline AgI at room temperature
Authors: Khaton Rahima , Kashiwagi Shin-ichiro , Iimori Toshifumi , Ohta Nobuhiro
Published: December 2008

A photoinduced reversible change in bulk resistance of polycrystalline AgI is observed at room temperature. The original yellow color of the sample changes to dark brown with UV (308 nm) photoirradiation, associated with the small decrease in the bulk resistance. A reversible switching of color between dark brown and yellow is observed by alternative UV-visible photoirradiation, associated with a switching between high and low resistance states. The observed reversible photoswitching is interpreted in terms of the photoinduced reversible change in the β-γ-polytype stacking structure of the polycrystalline AgI.
The impacts of large-scale, low-intensity fires on the forests of continental South-east Asia
Authors: Baker Patrick J. , Bunyavejchewin Sarayudh , Robinson Andrew P.
Published: December 2008

South-east Asia’s tropical forests harbour high levels of species richness and endemism. In continental South-east Asia strong rainfall seasonality driven by the Asian monsoon lead to ground-fires during the dry season in most years. How these fires influence the region’s landscape mosaic of evergreen and deciduous forests and the biodiversity they support is poorly understood. In this paper we report on the impacts of the El Niño–Southern Oscillation-induced 1997–98 fires that burned across much of western Thailand. We compare fire effects in the three common regional forest types – seasonal evergreen (SEG); mixed deciduous (MDF); and deciduous dipterocarp – and use data from a 50-ha study plot to evaluate the impacts of fire on these forests. We found few differences among the forest types. The fires created more large gaps in MDF than the other forest types. The SEG experienced greater fire mortality in the smallest size classes, abundant resprouting, and showed some evidence of lagged mortality among larger trees. The resilience of the SEG to fire and lack of major differences in fire effects among the forest types suggest that infrequent landscape-scale fires may have little effect on biodiversity in the landscape mosaic of seasonal tropical forests of continental South-east Asia.
A mixability theory for the role of sex in evolution
Authors: Livnat Adi , Papadimitriou Christos , Dushoff Jonathan , Feldman Marcus W.
Published: December 2008

The question of what role sex plays in evolution is still open despite decades of research. It has often been assumed that sex should facilitate the increase in fitness. Hence, the fact that it may break down highly favorable genetic combinations has been seen as a problem. Here, we consider an alternative approach. We define a measure that represents the ability of alleles to perform well across different combinations and, using numerical iterations within a classical population-genetic framework, show that selection in the presence of sex favors this ability in a highly robust manner. We also show that the mechanism responsible for this effect has been out of the purview of previous theory, because it operates during the evolutionary transient, and that the breaking down of favorable genetic combinations is an integral part of it. Implications of these results and more to evolutionary theory are discussed.
Effect of habitat area and isolation on fragmented animal populations
Authors: Prugh Laura R. , Hodges Karen E. , Sinclair Anthony R. E. , Brashares Justin S.
Published: December 2008

Habitat destruction has driven many once-contiguous animal populations into remnant patches of varying size and isolation. The underlying framework for the conservation of fragmented populations is founded on the principles of island biogeography, wherein the probability of species occurrence in habitat patches varies as a function of patch size and isolation. Despite decades of research, the general importance of patch area and isolation as predictors of species occupancy in fragmented terrestrial systems remains unknown because of a lack of quantitative synthesis. Here, we compile occupancy data from 1,015 bird, mammal, reptile, amphibian, and invertebrate population networks on 6 continents and show that patch area and isolation are surprisingly poor predictors of occupancy for most species. We examine factors such as improper scaling and biases in species representation as explanations and find that the type of land cover separating patches most strongly affects the sensitivity of species to patch area and isolation. Our results indicate that patch area and isolation are indeed important factors affecting the occupancy of many species, but properties of the intervening matrix should not be ignored. Improving matrix quality may lead to higher conservation returns than manipulating the size and configuration of remnant patches for many of the species that persist in the aftermath of habitat destruction.
De novo generation of a transmissible spongiform encephalopathy by mouse transgenesis
Authors: Sigurdson Christina J. , Nilsson K. Peter R. , Hornemann Simone , Heikenwalder Mathias , Manco Giuseppe , Schwarz Petra , Ott David , Rülicke Thomas , Liberski Pawel P. , Julius Christian , Falsig Jeppe , Stitz Lothar , Wüthrich Kurt , Aguzzi Adriano
Published: December 2008

Most transmissible spongiform encephalopathies arise either spontaneously or by infection. Mutations of
PRNP
, which encodes the prion protein, PrP, segregate with phenotypically similar diseases. Here we report that moderate overexpression in transgenic mice of mPrP(170N,174T), a mouse PrP with two point mutations that subtly affect the structure of its globular domain, causes a fully penetrant lethal spongiform encephalopathy with cerebral PrP plaques. This genetic disease was reproduced with 100% attack rate by intracerebral inoculation of brain homogenate to
tg
a
20
mice overexpressing WT PrP, and from the latter to WT mice, but not to PrP-deficient mice. Upon successive transmissions, the incubation periods decreased and PrP became more protease-resistant, indicating the presence of a strain barrier that was gradually overcome by repeated passaging. This shows that expression of a subtly altered prion protein, with known 3D structure, efficiently generates a prion disease.
Depicting by gesture
Authors: Streeck Jürgen
Published: December 2008

This paper deals with ways in which gestural “pictures” are made, i.e., manual depictions of phenomena in the world. The view that “iconic” gestures uniformly function by way of some resemblance between signifier and signified is rejected, giving way to an understanding of depiction by gesture as the achievement of a heterogeneous set of practices, some of which rely on relations of contiguity or indexicality to evoke commonly known objects or scenes. Others seem to be derivative of other representation methods (e.g., drawing on surfaces). The paper reviews some existing work on gestural depiction methods, offers a working heuristics, and illustrates some of its categories. It is suggested that some of the basic ways in which actions of the hands evoke the world in gesture correspond to fundamental modes of existence and activity of human hands in the world: hands depict by enacting their familiar, “real-world” capacities as users, transporters, experiencers, assemblers, molders, and shapers of things.
Clinical Practice Guideline for the Evaluation of Fever and Infection in Older Adult Residents of Long-Term Care Facilities: 2008 Update by the Infectious Diseases Society of America
Authors: High Kevin P. , Bradley Suzanne F. , Gravenstein Stefan , Mehr David R. , Quagliarello Vincent J. , Richards Chesley , Yoshikawa Thomas T.
Published: December 2008

Residents of long-term care facilities (LTCFs) are at great risk for infection. Most residents are older and have multiple comorbidities that complicate recognition of infection; for example, typically defined fever is absent in more than one-half of LTCF residents with serious infection. Furthermore, LTCFs often do not have the on-site equipment or personnel to evaluate suspected infection in the fashion typically performed in acute care hospitals. In recognition of the differences between LTCFs and hospitals with regard to hosts and resources present, the Infectious Diseases Society of America first provided guidelines for evaluation of fever and infection in LTCF residents in 2000. The guideline presented here represents the second edition, updated by data generated over the intervening 8 years. It focuses on the typical elderly person institutionalized with multiple chronic comorbidities and functional disabilities (e.g., a nursing home resident). Specific topic reviews and recommendations are provided with regard to what resources are typically available to evaluate suspected infection, what symptoms and signs suggest infection in a resident of an LTCF, who should initially evaluate the resident with suspected infection, what clinical evaluation should be performed, how LTCF staff can effectively communicate about possible infection with clinicians, and what laboratory tests should be ordered. Finally, a general outline of how a suspected outbreak of a specific infectious disease should be investigated in an LTCF is provided.
Developing a new publishing model for interdisciplinary research
Authors: PIDGEON Sean
Published: December 2008

It is widely recognized that interdisciplinary collaboration in science is crucial to the success of the research endeavor, but that long‐established institutional structures based on a firm division of the disciplines tend to make such teamwork difficult to achieve in practice. The development of the Wiley Interdisciplinary Reviews publishing model highlights some of the opportunities and challenges of crossing these traditional lines of demarcation.
ICAM-1–mediated Endothelial Nitric Oxide Synthase Activation via Calcium and AMP-activated Protein Kinase Is Required for Transendothelial Lymphocyte Migration
Authors: Martinelli Roberta , Gegg Matthew , Longbottom Rebecca , Adamson Peter , Turowski Patric , Greenwood John
Published: December 2008

As a gatekeeper of leukocyte trafficking the vasculature fulfills an essential immune function. We have recently shown that paracellular transendothelial lymphocyte migration is controlled by intercellular adhesion molecule 1 (ICAM-1)-mediated vascular endothelial cadherin (VEC) phosphorylation [Turowski et al., J. Cell Sci. 121, 29–37 (2008)]. Here we show that endothelial nitric oxide synthase (eNOS) is a critical regulator of this pathway. ICAM-1 stimulated eNOS by a mechanism that was clearly distinct from that utilized by insulin. In particular, phosphorylation of eNOS on S1177 in response to ICAM-1 activation was regulated by src family protein kinase, rho GTPase, Ca2+, CaMKK, and AMPK, but not Akt/PI3K. Functional neutralization of any component of this pathway or its downstream effector guanylyl cyclase significantly reduced lymphocyte diapedesis across the endothelial monolayer. In turn, activation of NO signaling promoted lymphocyte transmigration. The eNOS signaling pathway was required for T-cell transmigration across primary rat and human microvascular endothelial cells and also when shear flow was applied, suggesting that this pathway is ubiquitously used. These data reveal a novel and essential role of eNOS in basic immune function and provide a key link in the molecular network governing endothelial cell compliance to diapedesis.
Proteomic Identification and Characterization of a Novel Peroxisomal Adenine Nucleotide Transporter Supplying ATP for Fatty Acid β-Oxidation in Soybean and Arabidopsis
Authors: Arai Yuko , Hayashi Makoto , Nishimura Mikio
Published: December 2008

We have identified the novel protein Glycine max PEROXISOMAL ADENINE NUCLEOTIDE CARRIER (Gm PNC1) by proteomic analyses of peroxisomal membrane proteins using a blue native/SDS-PAGE technique combined with peptide mass fingerprinting. Gm PNC1, and the Arabidopsis thaliana orthologs At PNC1 and At PNC2, were targeted to peroxisomes. Functional integration of Gm PNC1 and At PNC2 into the cytoplasmic membranes of intact Escherichia coli cells revealed ATP and ADP import activities. The amount of Gm PNC1 in cotyledons increased until 5 d after germination under constant darkness and then decreased very rapidly in response to illumination. We investigated the physiological functions of PNC1 in peroxisomal metabolism by analyzing a transgenic Arabidopsis plant in which At PNC1 and At PNC2 expression was suppressed using RNA interference. The pnc1/2i mutant required sucrose for germination and suppressed the degradation of storage lipids during postgerminative growth. These results suggest that PNC1 contributes to the transport of adenine nucleotides that are consumed by reactions that generate acyl-CoA for peroxisomal fatty acid β-oxidation during postgerminative growth.
Ecosystem consequences of fish parasites*
Authors: Lafferty K. D.
Published: December 2008

In most aquatic ecosystems, fishes are hosts to parasites and, sometimes, these parasites can affect fish biology. Some of the most dramatic cases occur when fishes are intermediate hosts for larval parasites. For example, fishes in southern California estuaries are host to many parasites. The most common of these parasites,Euhaplorchis californiensis, infects the brain of the killifishFundulus parvipinnisand alters its behaviour, making the fish 10–30 times more susceptible to predation by the birds that serve as its definitive host. Parasites likeE. californiensisare embedded in food webs because they require trophic transmission. In the Carpinteria Salt Marsh estuarine food web, parasites dominate the links and comprise substantial amount of biomass. Adding parasites to food webs alters important network statistics such as connectance and nestedness. Furthermore, some free‐living stages of parasites are food items for free‐living species. For instance, fishes feed on trematode cercariae. Being embedded in food webs makes parasites sensitive to changes in the environment. In particular, fishing and environmental disturbance, by reducing fish populations, may reduce parasite populations. Indirect evidence suggests a decrease in parasites in commercially fished species over the past three decades. In addition, environmental degradation can affect fish parasites. For these reasons, parasites in fishes may serve as indicators of environmental impacts.
Histopathology of fish parasite infections – importance for populations
Authors: Feist S. W. , Longshaw M.
Published: December 2008

There is a bewildering array of fish parasites and probably all fish species harbour one or more species. Under normal conditions hosts often show little or no signs of infection, either clinically or at the organ and tissue level. All tissues can be infected, including the blood. Coelozoic species generally do not elicit significant host responses. Any developmental stages, however, where these migrate through the host tissues may produce a cellular response if resident for sufficient time. Histozoic parasites are generally more likely to evoke a pathological response since they are invariably in more intimate contact with immunocompetent host cells such as lymphocytes and phagocytes. In some cases, particularly with protistan infections, host response can be dramatic and cause significant disease due to organ dysfunction, with subsequent mortalities. Infections of the external epithelia caused by a variety of parasites including Monogenea and Copepoda are also significant, especially when large numbers are present. Resulting tissue necrosis compromises osmoregulation and facilitates entry of prokaryote infections. Parasites have numerous strategies to evade detection within the host, but even ‘protected’ intracellular forms, e.g. microsporeans and muscle‐invading myxozoans are recognized when they outgrow their accommodation or large cysts rupture, presenting parasite antigens to the host. In most instances, an evolutionary balance has been achieved between the host and the parasite and even when histopathology is evident, this is frequently localized and does not unduly impair performance of the affected organ. Examples include chronic inflammation, granuloma formation and focal fibrosis. This paper outlines the principle histopathological responses to a variety of parasite groups and provides a more detailed treatment of selected parasitic infections in marine and freshwater fish species to illustrate the relative importance of acute and chronic parasitic infections for host survival.
Impact of vascular endothelial growth factor receptor 1, 2, and 3 expression on the outcome of patients with gastric cancer
Authors: Hirashima Yoshinori , Yamada Yasuhide , Matsubara Junichi , Takahari Daisuke , Okita Natsuko , Takashima Atsuo , Kato Ken , Hamaguchi Tetsuya , Shirao Kuniaki , Shimada Yasuhiro , Taniguchi Hirokazu , Shimoda Tadakazu
Published: December 2008

Tumor angiogenesis is a multistep interactive process in which vascular endothelial growth factor (VEGF) and its receptors have a major role. However, the clinical significance of these molecules in gastric cancer (GC) remains unclear. Our study group comprised 86 patients who underwent gastrectomy and subsequently received chemotherapy for recurrent or residual tumor. Using immunohistochemical techniques, we analyzed the expression of VEGF receptors (VEGF‐R) 1, 2, and 3. VEGF‐R1 expression (defined as >5% staining) was found in the tumor cells of 65 tumors (76%) and in the stromal vessels of 36 tumors (42%). VEGF‐R2 expression was found in tumor cells and stromal vessels of 0 and 46 tumors (0 and 53%), respectively, and VEGF‐R3 expression was found in tumor cells and stromal vessels of 0 and 75 tumors (0 and 87%), respectively. Univariate analysis revealed that VEGF‐R expression correlated with shorter survival (VEGF‐R1 in stromal vessels, P = 0.001; VEGF‐R2 in stromal vessels, P = 0.009; VEGF‐R3 in stromal vessels, P = 0.005) and lower response to S‐1 (VEGF‐R1 in stromal vessels, P = 0.039). Multivariate analysis of potential prognostic factors showed that VEGF‐R1 and VEGF‐R2 in stromal vessels were independent predictors of poor outcome. Our data suggest that VEGF‐R expression can be a predictor of unfavorable clinical outcome in GC. VEGF‐R are promising candidates as therapeutic targets. (Cancer Sci 2009; 100: 310–315)
Expression of CUB domain containing protein (CDCP1) is correlated with prognosis and survival of patients with adenocarcinoma of lung
Authors: Ikeda Jun‐ichiro , Oda Tomofumi , Inoue Masayoshi , Uekita Takamasa , Sakai Ryuichi , Okumura Meinoshin , Aozasa Katsuyuki , Morii Eiichi
Published: December 2008

CUB domain containing protein (CDCP1), a transmembrane protein with intracellular tyrosine residues which are phosphorylated upon activation, is supposed to be engaged in proliferative activities and resistance to apoptosis of cancer cells. Expression level of CDCP1 was examined in lung adenocarcinoma, and its clinical implications were evaluated. CDCP1 expression was immunohistochemically examined in lung adenocarcinoma from 200 patients. Staining intensity of cancer cells was categorized as low and high in cases with tumor cells showing no or weak and strong membrane staining, respectively. MIB‐1 labeling index was also examined. There were 113 males and 87 females with median age of 63 years. Stage of disease was stage I in 144 cases (72.0%), II in 19 (9.5%), and III in 37 (18.5%). Sixty of 200 cases (30.0%) were categorized as CDCP1‐high, and the remaining as CDCP1‐low. Significant positive correlation was observed between CDCP1‐high expression and relapse rate (P < 0.0001), poor prognosis (P < 0.0001), MIB‐1 labeling index (P < 0.0001), and occurrence of lymph node metastasis (P = 0.0086). There was a statistically significant difference in disease‐free survival (DFS) (P < 0.0001) and overall survival (OS) rates (P < 0.0001) between patients with CDCP1‐high and CDCP1‐low tumors. Univariate analysis showed that lymph node status, tumor stage, and CDCP1 expression were significant factors for both OS and DFS. Multivariate analysis revealed that only CDCP1 expression was an independent prognostic factor for both OS and DFS. CDCP1 expression level is a useful marker for prediction of patients with lung adenocarcinoma (Cancer Sci 2009; 100: 429–433).