bluuebunny/crossref_metadata_2025 huggingface dataset:
Klinik und Genetik des Joubert-Syndroms
Authors: Hellenbroich Y. , Frost S.-K. , Gillessen-Kaesbach G.
Published: August 2010

Das Joubert-Syndrom ist ein überwiegend autosomal-rezessiv und sehr selten X-chromosomal erbliches Krankheitsbild, das durch eine muskuläre Hypotonie, ein irreguläres Atmungsmuster, Augenbewegungsstörungen, eine Ataxie, eine Entwicklungsverzögerung und ein „molar tooth sign“ in der Magnetresonanztomographie (MRT) als Ausdruck einer komplexen Klein- und Mittelhirnfehlbildung charakterisiert ist. Zahlreiche weitere klinische Auffälligkeiten können vorliegen, die häufigsten sind eine Nephronophthise, eine Retinopathie, Kolobome und eine Leberfibrose. Aufgrund der klinischen Variabilität und der Überlappung mit anderen Syndromen wurde der Begriff „Joubert syndrome and related disorders“ (JSRD) eingeführt. Bislang sind 10 Gene bekannt, deren Mutationen zu einem Joubert-Syndrom führen können. Die kodierten Proteine spielen alle eine funktionelle Rolle in Zilien.
Does the Pirani score predict relapse in clubfoot?
Authors: Goriainov Vitali , Judd Julia , Uglow Mike
Published: August 2010

Purpose

Presented here is a retrospective clinical audit of clubfoot patients to determine the value of the Pirani clubfoot scoring system at initial presentation in the estimation of subsequent relapse.

Methods

All clubfoot patients treated by the same surgeon from 2002 to 2006 were included. The treatment adhered to the standard protocol, involving weekly stretching and casting until the foot was corrected, followed by Achilles tenotomy and plasters for 3 weeks. Thereafter, the child was placed in a foot abduction splint. The severity of clubfoot was assessed using the Pirani scoring system, consisting of two sub-scores—the midfoot contracture score ( MFCS) and the hindfoot contracture score ( HFCS). The MFCS and HFCS can each be 0.0–3.0, giving rise to a total Pirani score ( TPS) of 0.0–6.0. Any recurrent deformity was classed as a relapse.

Results

Sixty-one clubfoot patients were treated. Five patients were lost to follow-up and six patients were excluded due to the presence of identified syndromes or having had primary treatment elsewhere. A total of 80 clubfeet were included. There were 17 relapses. The average interval between the initiation of foot abduction splint and relapse was 23 months. The median TPS was 3.5 in the no relapse group and 5.0 in the relapse group. The median MFCS was 1.5 in the no relapse group and 2.0 in the relapse group. The median HFCS was 2.0 in the no relapse group and 3.0 in the relapse group. Higher TPS and HFCS were statistically significant when the relapse group was analysed against the no relapse group ( P = 0.05 × 10−4 and 0.02 × 10−4, respectively).

Conclusions

Higher Pirani scores were associated with the late relapse group. The TPS and HFCS were shown to be statistically significant predictors of potential relapse. Closer follow-up is advised for patients at risk of relapse.
New insights into hominin lithic activities at FLK North Bed I, Olduvai Gorge, Tanzania
Authors: Diez-Martin F. , Sanchez Yustos P. , Domínguez-Rodrigo M. , Mabulla A.Z.P. , Bunn H.T. , Ashley G.M. , Barba R. , Baquedano E.
Published: August 2010

Recent work at FLK North (FLK N) has unearthed a new archaeological assemblage recovered with precise control of its stratigraphic position. In the present work, the technological study of the new lithic sample is described. The results show the co-occurrence in the same site of different technological behaviors. At FLK N, hominins were involved in both percussion/battering activities and through freehand and bipolar knapping, in core reduction. However, the reconstruction of the operational sequences shows that core reduction was probably a marginal behavior, while percussion/battering activities occurred more regularly throughout the sequence. If hominins were not involved in regular carcass processing, as recent taphonomic studies suggest, then hominins' sporadic and low-impact visits to the site over a long period of time must have been driven by other activities probably linked to the exploitation of alternative resources. Plant processing could have been a plausible explanation for hominin presence at FLK N.
Microfluidic System for Transmission Electron Microscopy
Authors: Ring Elisabeth A. , de Jonge Niels
Published: August 2010

We present a microfluidic system that maintains liquid flow in a specimen chamber for scanning transmission electron microscope (STEM) imaging. The specimen chamber consists of two ultrathin silicon nitride windows supported by silicon microchips. They are placed in a specimen holder that seals the sample from the vacuum in the electron microscope and incorporates tubing to and from the sample connected to a syringe pump outside the microscope. Using results obtained from fluorescence microscopy of microspheres flowing through the system, an equation to characterize the liquid flow through the system was calibrated. Gold nanoparticles of diameters of 30 and 100 nm moving in liquid were imaged with a 200 kV STEM. It was concluded that despite strong influences from Brownian motion, and sensitivity to small changes in the depth of the bypass channel, the electron microscopy flow data matched the calculated flow speed within an order of magnitude. The system allows for rapid (within a minute) liquid exchange, which can potentially be used, for example, to investigate the response of specimens, e.g., eukaryotic or bacterial cells, to certain stimuli.
Watershed modeling in the Tyrrhena Terra region of Mars
Authors: Mest Scott C. , Crown David A. , Harbert William
Published: August 2010

Watershed analyses from high‐resolution image (Viking, Mars Orbiter Camera, and Thermal Emission Imaging System) and topographic (Mars Orbiter Laser Altimeter [MOLA]) data are used to qualitatively and quantitatively characterize highland fluvial systems and analyze the role of water in the evolution of Tyrrhena Terra (13°S–30°S, 265°W–280°W), Mars. In this study, Geographical Information System software is used in conjunction with MOLA Digital Elevation Models to delineate drainage basin divides, extract valley networks, and derive basin and network morphometric parameters (e.g., drainage density, stream order, bifurcation ratio, and relief morphometry) useful in characterizing the geologic and climatic conditions of watershed formation, as well as for evaluating basin “maturity” and processes of watershed development. Model‐predicted valley networks and watershed boundaries, which are dependent on the degree to which pixel sinks are filled in the topographic data set and a channelization threshold, are evaluated against image and topographic data, slope maps, and detailed maps of valley segments from photogeologic analyses. Valley morphologies, crater/valley relationships, and impact crater distributions show that valleys in Tyrrhena Terra are ancient. Based on geologic properties of the incised materials, valley and network morphologies, morphometric parameters, and the presence of many gullies heading at or near‐crater rim crests, surface runoff, derived from rainfall or snowmelt, was the dominant erosional process; sapping may have only played a secondary role in valley formation in Tyrrhena Terra. Furthermore, spatial and temporal relationships of dissected highland materials and impact craters, suggests widespread, but relatively short‐lived, erosion by runoff with most activity in the Noachian period.
Observations from the High Resolution Imaging Science Experiment (HiRISE): Martian dust devils in Gusev and Russell craters
Authors: Verba Circe A. , Geissler Paul E. , Titus Timothy N. , Waller Devin
Published: August 2010

Two areas targeted for repeated imaging by detailed High Resolution Imaging Science Experiment (HiRISE) observations allow us to examine morphological differences and monitor seasonal variations of Martian dust devil tracks at two quite different locations. Russell crater (53.3°S, 12.9°E) is regularly imaged to study seasonal processes including deposition and sublimation of CO2 frost. Gusev crater (14.6°S, 175.4°E) has been frequently imaged in support of the Mars Exploration Rover mission. Gusev crater provides the first opportunity to compare “ground truth” orbital observations of dust devil tracks to surface observations of active dust plumes. Orbital observations show that dust devil tracks are rare, forming at a rate <1/110 that of the occurrence of active dust plumes estimated from Spirit's surface observations. Furthermore, the tracks observed from orbit are wider than typical plume diameters observed by Spirit. We conclude that the tracks in Gusev are primarily formed by rare, large dust devils. Smaller dust devils fail to leave tracks that are visible from orbit, perhaps because of limited surface excavation depths. Russell crater displays more frequent, smaller sinuous tracks than Gusev. This may be due to the thin dust cover in Russell, allowing smaller dust devils to penetrate through the bright dust layer and leave conspicuous tracks. The start of the dust devil season and peak activity are delayed in Russell in comparison to Gusev, likely because of its more southerly location. Dust devils in both sites travel in directions consistent with general circulation model (GCM)‐predicted winds, confirming a laboratory‐derived approach to determining dust devil travel directions based on track morphology.
Impacts of including forest understory brightness and foliage clumping information from multiangular measurements on leaf area index mapping over North America
Authors: Pisek Jan , Chen Jing M. , Alikas Krista , Deng Feng
Published: August 2010

A new leaf area index (LAI) data set in 10 day intervals with consideration of the understory reflectance and foliage clumping effects over North America for 1 year is developed. The data set brings effectively together measurements from multiple sensors with complementary capabilities (SPOT‐VEGETATION, Multiangle Imaging Spectroradiometer, POLDER). First, the temporal consistency analysis indicated the new product is on par with other available LAI data sets currently used by the community. Second, with the removal of the background (understory in forests, moss, litter, and soil) effect on the forest overstory LAI retrieval, slightly different LAI reductions were found between needleleaf and broadleaf forests. This is caused by the more clumped nature of needleleaf forests, especially at higher LAI values, which allows more light to penetrate through the overstory canopy, making the understory more visible for equal LAI as compared to broadleaf forests. This is found over a representative set of 105 CEOS Benchmark Land Multisite Analysis and Intercomparison of Products sites in North America used for indirect validation. Third, the data set was directly validated and compared with Moderate Resolution Imaging Spectroradiometer Collection 5 LAI product using results from the BigFoot project for available forest test sites. This study demonstrates that the fusion of data inputs between multiple sensors can indeed lead to improved products and that multiangle remote sensing can help us to address effectively the issues (separating the signal from the understory and overstory, foliage clumping) that could not be solved via the means of the conventional mono‐angle remote sensing.
Anarchy for the EMBC
Authors: Jacobs Howy
Published: August 2010

Howy bids a belated welcome to the new EMBO Director and Council Chair, and muses on how EMBO could learn from punk rock to increase its effectiveness and enthuse its members
Matrix Models as an Instrument to Support Generic Medicine Prescribing
Authors: Janknegt Robert , Brenninkmeijer Robert , Scott Mike , Simoens Steven
Published: August 2010

European countries have introduced various incentives to encourage physicians to prescribe generic medicines. This article aims to discuss matrix models, that is, decision tools to inform medicine prescribing in a transparent and reproducible way, and assess their implications for generic medicine use. To date, two types of matrix models, the System of Objectified Judgement Analysis and InforMatrix, have been introduced in the Netherlands; and the Safe Therapeutic Economic Pharmaceutical Selection (STEPSelect) method has been implemented in Northern Ireland. These matrix models in essence identify the most appropriate medicine to prescribe, taking into account clinically relevant and evidence-based selection criteria such as safety, efficacy, ease of use, tolerability, applicability and costs. As a result, matrix models are generally well accepted by both physicians and pharmacists. Generic medicines tend to receive favourable scores in matrix models because they have the same quality, safety and efficacy as originator medicines, but have a lower cost. In addition, the application of matrix models is estimated to generate substantial savings through, among other things, the increased prescribing of generic medicines. Future studies need to quantify the impact of matrix models on generic medicine prescribing rates.
Cherenkov electromagnetic instability excited by an oscillating relativistic electron beam in ion channel
Authors: Wang Zhen-Yu , Tang Chang-Jian , Peng Xiao-Dong
Published: August 2010

The Cherenkov electromagnetic instability excited by an oscillating relativistic electron beam in ion channel has been studied. It is shown that the complex boundary with beam-ion channel-plasma system and the perturbation of electrons induce several electromagnetic-electrostatic hybrid slow waves, which offer the possibility to excite the instability. Under such conditions, the electronic betatron motion plays a decisive role in exciting the instability. The necessary and sufficient conditions inducing the instability have been given, and related physical mechanisms have been discussed. Furthermore, the influence of the parameters, such as accelerating voltage, on the width of instability band and the growth rate of the instability has been given.
Symmetry-mode analysis of the ferroelectric transition in YMnO3
Authors: Kim Jinyoung , Koo Yang Mo , Sohn Kee-Sun , Shin Namsoo
Published: August 2010

Group theoretical methods were applied to elucidate the structural transition path and the polarization process in YMnO3. The atomic displacements derived from in situ high-temperature synchrotron x-ray powder diffraction data were decomposed into three symmetry-adapted modes (Γ2−, K1, and K3). The temperature dependence of the mode amplitudes confirmed the existence of two step-transitions. First, a coupled K3 and Γ2− mode lowered the symmetry from P63/mmc to P63cm at the phase-transition temperature of ∼1270 K, and held down to the TC. A single K3 mode, stabilized by hybridization between the Y and in-plane O ions, operated below TC with no additional symmetry breakage.
Whittaker modules for the Schrödinger–Witt algebra
Authors: Zhang Xiufu , Tan Shaobin , Lian Haifeng
Published: August 2010

In this paper, Whittaker modules for the Schrödinger–Witt algebra sv are defined. The Whittaker vectors and the irreducibility of the Whittaker modules are studied. sv has a triangular decomposition according to its Cartan subalgebra h: sv=sv−⊕h⊕sv+. For any Lie algebra homomorphism ψ:sv+→C, we can define Whittaker modules of type ψ. When ψ is nonsingular, the Whittaker vectors, the irreducibility, and the classification of Whittaker modules are completely determined. When ψ is singular, by constructing some special Whittaker vectors, we find that the Whittaker modules are all reducible. Moreover, we get some more precise results for special ψ.
Monitoring magnetization reversal and perpendicular anisotropy by the extraordinary Hall effect and anisotropic magnetoresistance.
Authors: Rosenblatt D. P. , Karpovski M. , Gerber A.
Published: August 2010

Simultaneous magnetotransport measurements of the extraordinary Hall effect and anisotropic magnetoresistance were used to monitor the normal and in-plane projections of magnetization in thin Co/Pd multilayers with perpendicular anisotropy. By reconstructing the magnitude and orientation of the magnetization vector we were able to track the reversal of magnetization and distinguish among the processes of coherent rotation and domain nucleation. The Stoner–Wohlfarth model was used to extract anisotropy constants from data collected during the coherent rotation. We show that magnetization reversal occurs coherently over a major part of the cycle under a canted magnetic field when the field's inclination exceeds a certain sample-dependent angle. The applicability range of the Stoner–Wohlfarth model and thus reliability of the calculated anisotropy constants is significantly improved when measurements are performed under canted fields.
On the existence of certain axisymmetric interior metrics
Authors: Angulo Santacruz C. , Batic D. , Nowakowski M.
Published: August 2010

One of the effects of noncommutative coordinate operators is that the delta function connected to the quantum mechanical amplitude between states sharp to the position operator gets smeared by a Gaussian distribution. Although this is not the full account of the effects of noncommutativity, this effect is, in particular, important as it removes the point singularities of Schwarzschild and Reissner–Nordström solutions. In this context, it seems to be of some importance to probe also into ringlike singularities which appear in the Kerr case. In particular, starting with an anisotropic energy-momentum tensor and a general axisymmetric ansatz of the metric together with an arbitrary mass distribution (e.g., Gaussian), we derive the full set of Einstein equations that the noncommutative geometry inspired Kerr solution should satisfy. Using these equations we prove two theorems regarding the existence of certain Kerr metrics inspired by noncommutative geometry.
Absolute measurements of fast neutrons using yttrium
Authors: Roshan M. V. , Springham S. V. , Rawat R. S. , Lee P. , Krishnan M.
Published: August 2010

Yttrium is presented as an absolute neutron detector for pulsed neutron sources. It has high sensitivity for detecting fast neutrons. Yttrium has the property of generating a monoenergetic secondary radiation in the form of a 909 keV gamma-ray caused by inelastic neutron interaction. It was calibrated numerically using MCNPX and does not need periodic recalibration. The total yttrium efficiency for detecting 2.45 MeV neutrons was determined to be fn∼4.1×10−4 with an uncertainty of about 0.27%. The yttrium detector was employed in the NX2 plasma focus experiments and showed the neutron yield of the order of 108 neutrons per discharge.
Nanodiamond-coated silicon cantilever array for chemical sensing
Authors: Ahmad Rezal K. , Parada Ana Carolina , Hudziak Steve , Chaudhary Aysha , Jackman Richard B.
Published: August 2010

Diamond offers attractive properties as a material for microelectromechanical chemical sensors but is difficult to process in comparison with silicon. Here a method for attaching detonation-derived nanodiamonds to prefabricated and mounted Si cantilever devices is described. It is shown that this hybrid device has a resonant frequency shifted down, compared to Si alone, by around 10% due to a higher spring constant. Exposure to 2,4-dinitrotoluene leads to an easily observed decrease in resonant frequency. The mechanisms behind these observations are discussed and the promise for this form of hybrid cantilever structure for chemical sensors applications highlighted.
Room temperature negative differential resistance characteristics of polar III-nitride resonant tunneling diodes
Authors: Bayram C. , Vashaei Z. , Razeghi M.
Published: August 2010

III-nitride resonant tunneling diodes (RTDs), consisting Al0.2Ga0.8N/GaN double-barrier (DB) active layers, were grown on c-plane lateral epitaxial overgrowth (LEO) GaN/sapphire and c-plane freestanding (FS) GaN. RTDs on both templates, fabricated into mesa diameters ranging from 5 to 35 μm, showed negative differential resistance (NDR) at room temperature. NDR characteristics (voltage and current density at NDR onset and current-peak-to-valley ratio) were analyzed and reported as a function of device size and substrate choice. Our results show that LEO RTDs perform as well as FS ones and DB active layer design and quality have been the bottlenecks in III-nitride RTDs.
Multiferroicity and magnetoelectric coupling in half-doped manganite La0.5Ca0.5MnO3
Authors: Zou Tao , Wang Fen , Liu Yi , Yan Li-Qin , Sun Young
Published: August 2010

We present experimental evidences to verify the peculiar multiferroics predicted in the half-doped manganite La0.5Ca0.5MnO3. The dielectric constant exhibits a frequency-independent peak just at the antiferromagnetic charge ordering transition temperature TCO, indicating a close correlation between the ferroelectriclike transition and charge ordering. In addition to a large magnetodielectric effect, the dynamic magnetoelectric coupling measurements provide solid evidences to an enhanced magnetoelectric coupling below TCO. Moreover, the magnetic field dependence of the coupling coefficient shows a close correlation with the magnetization hysteresis loop, which reveals that a large magnetoelectric coupling only persists in the charge ordering state.
Microfluidic parallel circuit for measurement of hydraulic resistance
Authors: Choi Sungyoung , Lee Myung Gwon , Park Je-Kyun
Published: August 2010

We present a microfluidic parallel circuit that directly compares the test channel of an unknown hydraulic resistance with the reference channel with a known resistance, thereby measuring the unknown resistance without any measurement setup, such as standard pressure gauges. Many of microfluidic applications require the precise transport of fluid along a channel network with complex patterns. Therefore, it is important to accurately characterize and measure the hydraulic resistance of each channel segment, and determines whether the device principle works well. However, there is no fluidic device that includes features, such as the ability to diagnose microfluidic problems by measuring the hydraulic resistance of a microfluidic component in microscales. To address the above need, we demonstrate a simple strategy to measure an unknown hydraulic resistance, by characterizing the hydraulic resistance of microchannels with different widths and defining an equivalent linear channel of a microchannel with repeated patterns of a sudden contraction and expansion.
Calculation of lifetime net income per year (LTNI/year) of Australian Holstein cows to validate the Australian profit ranking of their sires. 1. Genetic analyses and prediction of LTNI/year for cows still in the herd
Authors: Haile-Mariam M. , Bowman P. J. , Goddard M. E.
Published: August 2010

Birth, calving, milk yield, somatic cell count (SCC) and culling data of 274 000 AI-bred Holstein Friesian cows that were born between 1990 and 1998 from ~3400 herds were used to calculate lifetime net income per cow per year (LTNI/year). The main objective of this study was to identify an early measure of LTNI/year so that data of cows that are still in the herd can be used for predicting LTNI/year of cows. LTNI/year of cows that are still in the herd was predicted from net income per year (NI/year) assuming cows are culled at the end of each lactation and other traits that are measured early in the life of cows. LTNI/year is defined as NI up to the end of parity 9 or culling or death of cows per year of productive life.
On average maximum LTNI/year was attained by cows that completed seven lactations and LTNI/year of cows was the lowest if cows completed only one lactation. For cows that at least survived to second lactation LTNI/year increased with their NI/year at the end of the first parity and their relative production compared with their herdmates but decreased with the increase in average lactation SCC. The heritability of LTNI/year was 0.09 and had a genetic and residual correlation of 0.62 and 0.71, respectively, with productive life. The genetic correlation of LTNI/year with first-parity lactation protein and fat yield was high (~0.7 or above) but near zero with calving interval and lactation SCC. The genetic correlations between LTNI/year and NI/year up to the end of parity 1, 2, 3 and 4 were 0.84, 0.96, 0.99 and 1.0, respectively. The corresponding residual correlations were 0.55, 0.89, 0.96 and 0.98.
The genetic correlation between actual and predicted LTNI/year based only on cows that did not complete their lifetime (cows still in the herd) were 0.93, 0.96, 0.98 and 0.99 by the end of the first, second, third and fourth parity, respectively. The corresponding residual correlations were lower at 0.54, 0.70, 0.80 and 0.86, respectively. Estimates of genetic correlations between LTNI/year and NI/year based on calvings that happened 1 (1.0) to 4 (0.98) years earlier were unity. The corresponding residual correlations were slightly lower at 0.92 if the calvings that occurred 4 years ago and before were used, and near unity (0.98) if calvings that happened 1 year ago and before were used. In conclusion, the high genetic correlation (0.9 or above) between LTNI/year of cows and measures of lifetime NI/year based on cows that had a shorter opportunity to complete their lifetime suggests that genetic evaluation for LTNI/year is feasible even if some of the cows have incomplete lifetime data.
A phylogenetic study of Pimelea and Thecanthes (Thymelaeaceae): evidence from plastid and nuclear ribosomal DNA sequence data
Authors: Motsi M. Cynthia , Moteetee Annah N. , Beaumont Angela J. , Rye Barbara L. , Powell Martyn P. , Savolainen Vincent , van der Bank Michelle
Published: August 2010

A comprehensive molecular study, using sequence data from nuclear ITS rDNA and plastid rbcL and matK exons, rps16 intron, and the trnL-F intronic and intergenic spacer, was used to assess the taxonomic status of Thecanthes Wikstr., and to evaluate the relationships within Pimelea Banks & Sol. ex Gaertn. and Thecanthes (Thymelaeaceae). Both genera are Australasian and they constitute the subtribe Pimeleinae, which is characterised by a reduction to two stamens. Previous studies indicated a close relationship among Pimelea, Thecanthes and Gnidia L. species from tropical Africa. We conclude that Pimelea and Thecanthes form a strongly supported clade, with Thecanthes possibly included within Pimelea, although we await further data before formally proposing a series of new taxonomic combinations.
Morphometric study of Euchiton (Gnaphalieae: Asteraceae)
Authors: Flann Christina
Published: August 2010

A morphometric study was undertaken to survey taxa in the genus Euchiton Cass., distributed across Australia, New Zealand and South-east Asia. Phenetic analyses of herbarium specimens showed several taxa to be well delimited, including E. brassii (Mattf.) Anderb., E. breviscapus (Mattf.) Anderb., E. lateralis (C.J.Webb) Breitw. & J.M.Ward, E. limosus (D.G.Drury) Holub, E. litticola A.M.Buchanan, E. traversii (Hook.f.) Holub and E. umbricola (J.H.Willis) Anderb. However, the analyses showed that the remainder of Euchiton taxa are not yet satisfactorily resolved taxonomically. The distributions of E. involucratus (G.Forst.) Holub and E. sphaericus (Willd.) Holub were elucidated, although these widespread species would benefit from more research. Further research is necessary into species delimitation between E. paludosus (Petrie) Holub and E. polylepis (D.G.Drury) Breitw. & J.M.Ward and within the E. japonicus complex, including E. audax (D.G.Drury) Holub, E. collinus Cass., E. delicatus (D.G.Drury) Holub, E. ensifer (D.G.Drury) Holub, E. japonicus (Thunb.) Holub and E. ruahinicus (D.G.Drury) Breitw. & J.M.Ward. Recognition of a proposed taxon E. ‘gracilis’ was not supported and description at this point is not recommended. The New Zealand material of E. audax, E. delicatus and E. ensifer was shown to differ from the Australian material in the micromorphology of the cypselae. Euchiton collinus is considered a synonym of E. japonicus, which also includes the Australian material attributed to E. audax, E. delicatus and E. ensifer. The presence of E. limosus in Australia was confirmed, with it differing from E. involucratus in having glabrous cypselae with paired papillae in both Australian and New Zealand material. Generic boundaries of Euchiton are problematic. The generic placement of Gnaphalium clemensiae Mattf. and E. umbricola remains unresolved. Insufficient data were available to make taxonomic conclusions regarding the generic placement of G. chiliastrum (Mattf.) P.Royen and G. heleios P.Royen from New Guinea.
RNA helicase A is a DNA-binding partner for EGFR-mediated transcriptional activation in the nucleus
Authors: Huo Longfei , Wang Ying-Nai , Xia Weiya , Hsu Sheng-Chieh , Lai Chien-Chen , Li Long-Yuan , Chang Wei-Chao , Wang Yan , Hsu Ming-Chuan , Yu Yung-Luen , Huang Tzu-Hsuan , Ding Qingqing , Chen Chung-Hsuan , Tsai Chang-Hai , Hung Mien-Chie
Published: August 2010

EGF induces the translocation of EGF receptor (EGFR) from the cell surface to the nucleus where EGFR activates gene transcription through its binding to an AT-rich sequence (ATRS) of the target gene promoter. However, how EGFR, without a DNA-binding domain, can bind to the gene promoter is unclear. In the present study, we show that RNA helicase A (RHA) is an important mediator for EGFR-induced gene transactivation. EGF stimulates the interaction of EGFR with RHA in the nucleus of cancer cells. The EGFR/RHA complex then associates with the target gene promoter through binding of RHA to the ATRS of the target gene promoter to activate its transcription. Knockdown of RHA expression in cancer cells abrogates the binding of EGFR to the target gene promoter, thereby reducing EGF/EGFR-induced gene expression. In addition, interruption of EGFR–RHA interaction decreases the EGFR-induced promoter activity. Consistently, we observed a positive correlation of the nuclear expression of EGFR, RHA, and cyclin D1 in human breast cancer samples. These results indicate that RHA is a DNA-binding partner for EGFR-mediated transcriptional activation in the nucleus.
CCAAT/enhancer binding protein delta (C/EBPδ, CEBPD)-mediated nuclear import of FANCD2 by IPO4 augments cellular response to DNA damage
Authors: Wang Jun , Sarkar Tapasree Roy , Zhou Ming , Sharan Shikha , Ritt Daniel A. , Veenstra Timothy D. , Morrison Deborah K. , Huang A-Mei , Sterneck Esta
Published: August 2010

Maintenance of genomic integrity is an essential cellular function. We previously reported that the transcription factor and tumor suppressor CCAAT/enhancer binding protein δ (C/EBPδ, CEBPD; also known as “NFIL-6β”) promotes genomic stability. However, the molecular mechanism was not known. Here, we show that C/EBPδ is a DNA damage-induced gene, which supports survival of mouse bone marrow cells, mouse embryo fibroblasts (MEF), human fibroblasts, and breast tumor cells in response to the DNA cross-linking agent mitomycin C (MMC). Using gene knockout, protein depletion, and overexpression studies, we found that C/EBPδ promotes monoubiquitination of the Fanconi anemia complementation group D2 protein (FANCD2), which is necessary for its function in replication-associated DNA repair. C/EBPδ interacts with FANCD2 and importin 4 (IPO4, also known as “Imp4” and “RanBP4”) via separate domains, mediating FANCD2–IPO4 association and augmenting nuclear import of FANCD2, a prerequisite for its monoubiquitination. This study identifies a transcription-independent activity of C/EBPδ in the DNA damage response that may in part underlie its tumor suppressor function. Furthermore, we report a function of IPO4 and nuclear import in the Fanconi anemia pathway of DNA repair.
Ubiquitination of lysine-331 by Kaposi's sarcoma-associated herpesvirus protein K5 targets HFE for lysosomal degradation
Authors: Rhodes David A. , Boyle Louise H. , Boname Jessica M. , Lehner Paul J. , Trowsdale John
Published: August 2010

The nonclassical MHC class I-related (MHC-I) molecule HFE controls cellular iron homeostasis by a mechanism that has not been fully elucidated. We examined the regulation of HFE by K5, the E3 ubiquitin ligase encoded by Kaposi's sarcoma-associated herpesvirus (KSHV/HHV8), that is known to down-regulate classical MHC-I. K5 down-regulated HFE efficiently, using polyubiquitination of the membrane proximal lysine in the HFE cytoplasmic tail (K331), to target the molecule for degradation via ESCRT1/TSG101-dependent sorting from endosomes to multivesicular bodies (MVBs)/lysosomes. In the primary effusion lymphoma cell line BC-3, which carries latent KSHV, HFE was degraded rapidly upon virus reactivation. HFE was ubiquitinated on lysine-331 in unactivated BC-3 cells, conditions where K5 was not detectable, consistent with an endogenous E3 ubiquitin ligase controlling HFE expression. The results show regulated expression of HFE by ubiquitination, consistent with a role in cellular iron homeostasis, a molecular mechanism targeted by KSHV to achieve a positive iron balance.
D1 and D2 dopamine receptors in separate circuits cooperate to drive associative long-term potentiation in the prefrontal cortex
Authors: Xu Tai-Xiang , Yao Wei-Dong
Published: August 2010

Dopamine release associated with motivational arousal is thought to drive goal-directed learning and consolidation of acquired memories. This dopamine hypothesis of learning and motivation directly suggests that dopamine is necessary for modifications of excitatory synapses in dopamine terminal fields, including the prefrontal cortex (PFC), to “stamp in” posttrial memory traces. It is unknown how such enabling occurs in native circuits tightly controlled by GABAergic inhibitory tone. Here we report that dopamine, via both D1-class receptors (D1Rs) and D2-class receptors (D2Rs), enables the induction of spike timing–dependent long-term potentiation (t-LTP) in layer V PFC pyramidal neurons over a “window” of more than 30 ms that is otherwise closed under intact inhibitory constraint. Dopamine acts at D2Rs in local GABAergic interneurons to suppress inhibitory transmission, gating the induction of t-LTP. Moreover, dopamine activates postsynaptic D1Rs in excitatory synapses to allow t-LTP induction at a substantially extended, normally ineffective, timing interval (+30 ms), thus increasing the associability of prepost coincident stimuli. Although the D2R-mediated disinhibition alone is sufficient to gate t-LTP at a normal timing (+10 ms), t-LTP at +30 ms requires concurrent activation of both D1Rs and D2Rs. Our results illustrate a previously unrecognized circuit-level mechanism by which dopamine receptors in separate microcircuits cooperate to drive Hebbian synaptic plasticity across a significant temporal window under intact inhibition. This mechanism should be important in functioning of interconnected PFC microcircuits, in which D1Rs and D2Rs are not colocalized but their coactivation is necessary.
Image-matching during ant navigation occurs through saccade-like body turns controlled by learned visual features
Authors: Lent David. D. , Graham Paul , Collett Thomas S.
Published: August 2010

Visual memories of landmarks play a major role in guiding the habitual foraging routes of ants and bees, but how these memories engage visuo-motor control systems during guidance is poorly understood. We approach this problem through a study of image matching, a navigational strategy in which insects reach a familiar place by moving so that their current retinal image transforms to match a memorized snapshot of the scene viewed from that place. Analysis of how navigating wood ants correct their course when close to a goal reveals a significant part of the mechanism underlying this transformation. Ants followed a short route to an inconspicuous feeder positioned at a fixed distance from a vertical luminance edge. They responded to an unexpected jump of the edge by turning to face the new feeder position specified by the edge. Importantly, the initial speed of the turn increased linearly with the turn's amplitude. This correlation implies that the ants’ turns are driven initially by their prior calculation of the angular difference between the current retinal position of the edge and its desired position in their memorized view. Similar turns keep ants to their path during unperturbed routes. The neural circuitry mediating image-matching is thus concerned not only with the storage of views, but also with making exact comparisons between the retinal positions of a visual feature in a memorized view and of the same feature in the current retinal image.
Nonuniversal power law scaling in the probability distribution of scientific citations
Authors: Peterson George J. , Pressé Steve , Dill Ken A.
Published: August 2010

We develop a model for the distribution of scientific citations. The model involves a dual mechanism: in the
direct mechanism
, the author of a new paper finds an old paper
A
and cites it. In the
indirect mechanism
, the author of a new paper finds an old paper
A
only
via
the reference list of a newer intermediary paper
B
, which has previously cited
A
. By comparison to citation databases, we find that papers having few citations are cited mainly by the direct mechanism. Papers already having many citations (“classics”) are cited mainly by the indirect mechanism. The indirect mechanism gives a power-law tail. The “tipping point” at which a paper becomes a classic is about 25 citations for papers published in the Institute for Scientific Information (ISI) Web of Science database in 1981, 31 for
Physical Review D
papers published from 1975–1994, and 37 for all publications from a list of high
h
-index chemists assembled in 2007. The power-law exponent is not universal. Individuals who are highly cited have a systematically smaller exponent than individuals who are less cited.
Subgroup II PAK-mediated phosphorylation regulates Ran activity during mitosis
Authors: Bompard Guillaume , Rabeharivelo Gabriel , Frank Marie , Cau Julien , Delsert Claude , Morin Nathalie
Published: August 2010

Ran is an essential GTPase that controls nucleocytoplasmic transport, mitosis, and nuclear envelope formation. These functions are regulated by interaction of Ran with different partners, and by formation of a Ran-GTP gradient emanating from chromatin. Here, we identify a novel level of Ran regulation. We show that Ran is a substrate for p21-activated kinase 4 (PAK4) and that its phosphorylation on serine-135 increases during mitosis. The endogenous phosphorylated Ran and active PAK4 dynamically associate with different components of the microtubule spindle during mitotic progression. A GDP-bound Ran phosphomimetic mutant cannot undergo RCC1-mediated GDP/GTP exchange and cannot induce microtubule asters in mitotic Xenopus egg extracts. Conversely, phosphorylation of GTP-bound Ran facilitates aster nucleation. Finally, phosphorylation of Ran on serine-135 impedes its binding to RCC1 and RanGAP1. Our study suggests that PAK4-mediated phosphorylation of GDP- or GTP-bound Ran regulates the assembly of Ran-dependent complexes on the mitotic spindle.
Somatic hypermutation as a generator of antinuclear antibodies in a murine model of systemic autoimmunity
Authors: Guo Wenzhong , Smith Diana , Aviszus Katja , Detanico Thiago , Heiser Ryan A. , Wysocki Lawrence J.
Published: August 2010

Systemic lupus erythematosus (SLE) is characterized by high-avidity IgG antinuclear antibodies (ANAs) that are almost certainly products of T cell–dependent immune responses. Whether critical amino acids in the third complementarity-determining region (CDR3) of the ANA originate from V(D)J recombination or somatic hypermutation (SHM) is not known. We studied a mouse model of SLE in which all somatic mutations within ANA V regions, including those in CDR3, could be unequivocally identified. Mutation reversion analyses revealed that ANA arose predominantly from nonautoreactive B cells that diversified immunoglobulin genes via SHM. The resolution afforded by this model allowed us to demonstrate that one ANA clone was generated by SHM after a VH gene replacement event. Mutations producing arginine substitutions were frequent and arose largely (66%) from base changes in just two codons: AGC and AGT. These codons are abundant in the repertoires of mouse and human V genes. Our findings reveal the predominant role of SHM in the development of ANA and underscore the importance of self-tolerance checkpoints at the postmutational stage of B cell differentiation.
The multiannual management plan for cod in the Baltic Sea: reactions and sentiments in two German fishing communities
Authors: Strehlow Harry V.
Published: August 2010

Strehlow, H. V. 2010. The multiannual management plan for cod in the Baltic Sea: reactions and sentiments in two German fishing communities. – ICES Journal of Marine Science, 67: 1963–1971. Just before and one and a half years after the implementation of the Multiannual Management Plan for the Cod Stocks in the Baltic Sea, the same two fishing communities on the German Baltic coast were visited to try to understand the impacts of the plan. Such information is a prerequisite for policy-makers to mitigate possible negative consequences on specific fleet sectors. During semi-structured interviews, observations, and group discussions, information on the reactions and the sentiments about the plan prevailing in the communities was collected. In general, the plan found widespread approval, because it improved planning reliability for fishers and cooperatives considerably. Conversely, the reduction in fishing effort stipulated in the plan has had strong adverse effects on small-scale fishers. The survey furthermore revealed that this fishery segment using passive fishing gear is among the most vulnerable, because it is the interest group with the lowest income, little resilience to cope with further restrictions, and no lobby to improve their position.
Democratic Compromise: A Latent Variable Analysis of Ten Measures of Regime Type
Authors: Pemstein Daniel , Meserve Stephen A. , Melton James
Published: August 2010

Using a Bayesian latent variable approach, we synthesize a new measure of democracy, the Unified Democracy Scores (UDS), from 10 extant scales. Our measure eschews the difficult—and often arbitrary—decision to use one existing democracy scale over another in favor of a cumulative approach that allows us to simultaneously leverage the measurement efforts of numerous scholars. The result of this cumulative approach is a measure of democracy that, for every country-year, is at least as reliable as the most reliable component measure and is accompanied by quantitative estimates of uncertainty in the level of democracy. Moreover, for those who wish to continue using previously existing scales or to evaluate research performed using those scales, we extract information from the new measure to perform heretofore impossible direct comparisons between component scales. Specifically, we estimate the relative reliability of the constituent indicators, compare the specific ordinal levels of each of the existing measures in relationship to one another and assess overall levels of disagreement across raters. We make the UDS and associated parameter estimates freely available online and provide a detailed tutorial that demonstrates how to best use the UDS in applied work.
A Two-handed Jaw-thrust Technique Is Superior to the One-handed “EC-clamp” Technique for Mask Ventilation in the Apneic Unconscious Person
Authors: Joffe Aaron M. , Hetzel Scott , Liew Elaine C.
Published: August 2010

Background

Mask ventilation is considered a "basic" skill for airway management. A one-handed "EC-clamp" technique is most often used after induction of anesthesia with a two-handed jaw-thrust technique reserved for difficult cases. Our aim was to directly compare both techniques with the primary outcome of air exchange in the lungs.

Methods

Forty-two elective surgical patients were mask-ventilated after induction of anesthesia by using a one-handed "EC-clamp" technique and a two-handed jaw-thrust technique during pressure-control ventilation in randomized, crossover fashion. When unresponsive to a jaw thrust, expired tidal volumes were recorded from the expiratory limb of the anesthesia machine each for five consecutive breaths. Inadequate mask ventilation and dead-space ventilation were defined as an average tidal volume less than 4 ml/kg predicted body weight or less than 150 ml/breath, respectively. Differences in minute ventilation and tidal volume between techniques were assessed with the use of a mixed-effects model.

Results

Patients were (mean ± SD) 56 ± 18 yr old with a body mass index of 30 ± 7.1 kg/m. Minute ventilation was 6.32 ± 3.24 l/min with one hand and 7.95 ± 2.70 l/min with two hands. The tidal volume was 6.80 ± 3.10 ml/kg predicted body weight with one hand and 8.60 ± 2.31 ml/kg predicted body weight with two hands. Improvement with two hands was independent of the order used. Inadequate or dead-space ventilation occurred more frequently during use of the one-handed compared with the two-handed technique (14 vs. 5%; P = 0.013).

Conclusion

A two-handed jaw-thrust mask technique improves upper airway patency as measured by greater tidal volumes during pressure-controlled ventilation than a one-handed "EC-clamp" technique in the unconscious apneic person.
Remifentanil Versus Fentanyl for Esophagogastroduodenoscopy in Children
Authors: Hirsh Irina , Lerner Aaron , Shnaider Ilia , Reuveni Amit , Pacht Avi , Segol Ori , Pizov Reuven
Published: August 2010

Objectives:

We compared sedation by propofol combined with either fentanyl or remifentanil in pediatric outpatients undergoing diagnostic esophagogastroduodenoscopy.

Patients and Methods:

Forty‐two children scheduled for esophagogastroduodenoscopy in our institution were randomly assigned to receive 2 mg/kg propofol plus either 1 μg/kg bolus of fentanyl (group F; n = 20) or 0.5 μg/kg bolus of remifentanil (group R; n = 22). Cardiorespiratory parameters, sedation level, adverse effects related to the drugs and/or to the procedure, ease of performance for the endoscopist, and time to awakening were analyzed.

Results:

There were no clinically significant changes in hemodynamics. Apnea periods >20 seconds and decreases in SaO2 <90% occurred more frequently in group R (31.8% vs 0%, P < 0.01, and 27.3% vs 5.0%, P > 0.05, respectively). Children in group R had significantly shorter average time to awakening: 9.5 ± 5.6 vs 16.5 ± 10.5 minutes (P = 0.01), and received a significantly lower total dose of propofol (P = 0.034). Adverse effects within the first 24 hours postprocedure occurred less frequently in group R (P = 0.03).

Conclusions:

Remifentanil in combination with propofol provides good analgesic and sedative effects, which were shorter lasting compared with fentanyl‐based sedation, and caused fewer delayed adverse effects. The use of remifentanil was associated with respiratory depression, emphasizing the need for experienced anesthesiologists.