bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurements of adipocity and high blood pressure among children and adolescents living in Belo Horizonte
Authors: Ribeiro Robespierre C. , Lamounier Joel A. , Oliveira Reynaldo G. , Bensenor Isabela M. , Lotufo Paulo A.
Published: July 2009

Objective

To verify an association, if it exists, between obesity and blood pressure raised beyond the 90th percentile in children and adolescents, and to determine the measure of adiposity that best correlates with blood pressure in these subjects.

Design

Cross-sectional study.

Setting

A school-based study in Belo Horizonte, Brazil.

Participants

We selected randomly 1,403 students, aged from 6 to 18 years, from 545,046 students attending 521 public and private schools. Those selected completed the study.

Main measures of outcome

We recorded the weight, height, skin fold in the triceps, subscapular, and suprailiac areas, waist and hip circumference, body-mass index, and resting systolic and diastolic blood pressures using a mercury sphygmomanometer.

Results

In univariate analyses, body mass index greater or lesser than 85th percentile, measurements of skin thickness in the subscapular and suprailiac areas, and the sum of all measurements of skinfold thickness, were associated with both systolic and diastolic measurements of blood pressure. After multivariate analyses that adjusted for all measurements of adiposity except itself, and age, race, and socioeconomic state, we found that the increased body mass index was associated with a 3.6-fold increased frequency of elevated systolic measurements of blood pressure, with 95% confidence intervals from 2.2 to 5.8, and a 2.7-fold increased frequency of elevated measurements of diastolic blood pressure, with 95% confidence intervals from 1.9 to 4.0.

Conclusions

Body-mass index serves as a better predictor of elevated blood pressure among children than do local measurements of adiposity.
Improvement of SuperDARN velocity measurements by estimating the index of refraction in the scattering region using interferometry
Authors: Gillies R. G. , Hussey G. C. , Sofko G. J. , McWilliams K. A. , Fiori R. A. D. , Ponomarenko P. , St.‐Maurice J.‐P.
Published: July 2009

In past calculations of convective velocities from Super Dual Auroral Radar Network (SuperDARN) HF radar observations, the refractive index in the scattering region has not been taken into account, and therefore the inferred ionospheric velocities may be underestimated. In light of the significant contribution by SuperDARN to ionospheric and magnetospheric research, it is important to refine the velocity determination. The refractive index in the ionosphere at SuperDARN observation F region altitudes has typical values between 0.8 and close to unity. In the scattering region, where conditions are more extreme, the index of refraction may be much lower. A simple application of Snell's law in spherical coordinates (Bouguer's law) suggests that a proxy for the index of refraction at the scattering location can be determined by measuring the elevation angle of the returned ionospheric radar signal. Using this approximation for refractive index, the Doppler velocity calculation can be refined for each SuperDARN ionospheric echo, using the elevation angles obtained from the SuperDARN interferometer data. A velocity comparison of DMSP and SuperDARN observations has revealed that the SuperDARN speeds were systematically lower than the DMSP speeds. A linear regression analysis of the velocity comparisons found a best fit slope of 0.74. When the elevation angle data were used to estimate refractive index, the best fit slope rose 12% to 0.83. As most SuperDARN radars employ an interferometer antenna array for elevation angle measurements, the improvement in velocity estimates can be done routinely using the method outlined in this paper.
Mixed layer temperature balance in the eastern Indian Ocean during the 2006 Indian Ocean dipole
Authors: Horii Takanori , Masumoto Yukio , Ueki Iwao , Hase Hideaki , Mizuno Keisuke
Published: July 2009

An anomalous climate mode, the positive Indian Ocean dipole (IOD), occurred in 2006 with the anomalous sea surface temperature (SST) distribution in the tropical Indian Ocean. Using various types of observational data, we investigated the temperature variation in the surface mixed layer in the eastern Indian Ocean to clarify the processes that produced the anomalous SST variation in 2006. Analysis was conducted at an intraseasonal time scale and focused on a location (5°S, 95°E) where in situ measurements by the Triangle Trans‐Ocean Buoy Network were available. Temporal changes in the mixed layer temperature were obtained from the buoy data. Air‐sea heat fluxes and horizontal heat advection were estimated from the buoy data, satellite‐based data, and reanalysis products. Heat balance analysis demonstrated that air‐sea heat fluxes and horizontal heat advection mainly accounted for the mixed layer temperature variation. The results indicate that the relative importance of the heat fluxes and horizontal heat advections changed remarkably with the onset of the IOD. During January to mid‐May 2006, before the onset of the IOD, the temperature variation was mainly explained by the net surface heat flux at an intraseasonal time scale. During the IOD in late August to November 2006, the northwestward horizontal temperature gradient and the surface current produced large horizontal heat advection that exceeded the contribution of surface heat fluxes. These results confirm the importance of oceanic processes in the evolution of the IOD, and the heat balance analysis would be a fundamental example in validating model outputs for the Indian Ocean.
Development of an HF selection tool based on the Electron Density Assimilative Model near‐real‐time ionosphere
Authors: Angling M. J. , Shaw J. , Shukla A. K. , Cannon P. S.
Published: July 2009

The Electron Density Assimilative Model (EDAM) has been developed to provide real‐time characterization of the ionosphere. A thin‐client Web‐based ionospheric situational awareness tool, which relies on data from EDAM, has been developed. The tool provides the high‐frequency (HF) maximum usable frequency (MUF) and the optimum working frequency (FOT) on the basis of the current ionospheric electron density grid from EDAM. Two validations are reported. First, EDAM has been tested against a set of vertical ionosondes. The results show performance comparable to that of the Utah State University Global Assimilation of Ionospheric Measurements Gauss–Markov Kalman filter model. Second, MUFs estimated from EDAM were compared with those measured on an oblique path from New Zealand to Australia. Although EDAM demonstrates better performance than a monthly median model in some days, over the whole test period EDAM performed no better than the international reference ionosphere. This can be attributed to the lack of input GPS total electron content (TEC) data near the midpoint of the path and a probable TEC bias in the background model.
Episodic orogenic front migration in the northern Andes: Constraints from low‐temperature thermochronology in the Eastern Cordillera, Colombia
Authors: Parra Mauricio , Mora Andres , Sobel Edward R. , Strecker Manfred R. , González Román
Published: July 2009

New thermochronometric data from the Eastern Cordillera of the Colombian Andes reveal diachronous exhumation associated with Cenozoic contractional deformation in this sector of the northern Andes. We present a comprehensive account of exhumation patterns along a 150‐km‐long, across‐strike transect between ∼4° and 6°N by integrating 29 new apatite fission track (AFT) ages and 17 new zircon fission track (ZFT) ages with sparse published thermochronological data from this area. Our data reveal episodic eastward migration of the orogenic front at an average rate of 2.5–2.7 mm/a during the Late Cretaceous‐Cenozoic. We identify three major stages of orogen propagation: (1) slow propagation (0.5–3.1 mm/a) until early Eocene; (2) rapid orogenic advance (4.0–18.0 mm/a) during middle‐late Eocene, which accounts for ∼86% of the orogen's present width; and (3) slow orogen propagation (1.2–2.1 mm/a) from Oligocene to Holocene times. Our data demonstrate that in the course of changes in plate kinematics, the presence of inherited crustal anisotropies, such as the former rift‐bounding faults of the Eastern Cordillera, favor a nonsystematic progression of foreland basin deformation through time by preferentially concentrating accommodation of slip and thrust loading along these zones of weakness.
Observational evidence of an intensifying hydrological cycle in northern Canada
Authors: Déry Stephen J. , Hernández‐Henríquez Marco A. , Burford Jason E. , Wood Eric F.
Published: July 2009

Trends and variability in the 1964–2007 annual streamflow for 45 rivers spanning 5.2 × 106 km2 of northern Canada are investigated. Discharge averages 1153 km3 yr−1 with a standard deviation of 71.4 km3 yr−1 and coefficient of variation (CVQ) of 6.2% over the 44‐year period. A trend analysis reveals a recent (1989–2007) 15.5% increase in the annual flows owing to much‐above average values recorded over the past decade. Trends in CVQ computed from 11‐year moving windows of annual streamflows exhibit spatially coherent signals with increasing variability across most of northern Canada, excluding some rivers with outlets to the Labrador Sea and eastern James Bay. For the period of interest, 46% and 30% of the available gauged area and river discharge, respectively, experienced detectable increases in variability. This provides observational evidence of an intensifying hydrological cycle in northern Canada, consistent with other regions of the pan‐Arctic domain.
Pancreatic stellate cells can form new β-like cells
Authors: Docherty Kevin
Published: July 2009

Regenerative medicine, including cell-replacement strategies, may have an important role in the treatment of Type 1 and Type 2 diabetes, both of which are associated with decreased islet cell mass. To date, significant progress has been made in deriving insulin-secreting β-like cells from human ES (embryonic stem) cells. However, the cells are not fully differentiated, and there is a long way to go before they could be used as a replenishable supply of insulin-secreting β-cells for transplantation. For this reason, adult pancreatic stem cells are seen as an alternative source that could be expanded and differentiated ex vivo, or induced to form new islets in situ. In this issue of the Biochemical Journal, Mato et al. used drug selection to purify a population of stellate cells from explant cultures of pancreas from lactating rats. The selected cells express some stem-cell markers and can be grown for over 2 years as a fibroblast-like monolayer. When plated on extracellular matrix, along with a cocktail of growth factors that included insulin, transferrin, selenium and the GLP-1 (glucagon-like peptide-1) analogue exendin-4, the cells differentiated into cells that expressed many of the phenotypic markers characteristic of a β-cell, and exhibited an insulin-secretory response, albeit weak, to glucose. The ability to purify this cell population opens up the possibility of unravelling the mechanisms that control self-renewal and differentiation of pancreatic cells that share some of the properties of stem cells.
Promoting assembly and bundling of FtsZ as a strategy to inhibit bacterial cell division: a new approach for developing novel antibacterial drugs
Authors: Beuria Tushar K. , Singh Parminder , Surolia Avadhesha , Panda Dulal
Published: July 2009

FtsZ plays an essential role in bacterial cell division. We have used the assembly of FtsZ as a screen to find antibacterial agents with a novel mechanism of action. The effects of 81 compounds of 29 different structural scaffolds on FtsZ assembly in vitro were examined using a sedimentation assay. Out of these 81 compounds, OTBA (3-{5-[4-oxo-2-thioxo-3-(3-trifluoromethyl-phenyl)-thiazolidin-5-ylidenemethyl]-furan-2-yl}-benzoic acid) was found to promote FtsZ assembly in vitro. OTBA increased the assembly of FtsZ, caused bundling of FtsZ protofilaments, prevented dilution-induced disassembly of FtsZ protofilaments and decreased the GTPase activity in vitro. It bound to FtsZ with an apparent dissociation constant of 15±1.5 μM. Furthermore, OTBA inhibited the proliferation of Bacillus subtilis 168 cells with an MIC (minimum inhibitory concentration) of 2 μM, whereas it exerted minimal effects on mammalian cell proliferation, indicating that it might have a potential use as an antibacterial drug. In the effective proliferation inhibitory concentration range, OTBA induced filamentation in bacteria and also perturbed the formation of the cytokinetic Z-rings in bacteria. However, the agent neither perturbed the membrane structures nor affected the nucleoid segregation in B. subtilis cells. The results suggested that the OTBA inhibited bacterial cytokinesis by perturbing the formation and functioning of the Z-ring via altering FtsZ assembly dynamics. The antibacterial mechanism of action of OTBA is similar to that of the widely used anticancer drug paclitaxel, which inhibits cancer cell proliferation by promoting the assembly of tubulin, a eukaryotic homologue of FtsZ.
Matrix metalloproteinase-2 predicts mortality in patients with acute coronary syndrome
Authors: Dhillon Onkar S. , Khan Sohail Q. , Narayan Hafid K. , Ng Kelvin H. , Mohammed Noor , Quinn Paulene A. , Squire Iain B. , Davies Joan E. , Ng Leong L.
Published: July 2009

The aim of the present study was to investigate the predictive value of MMP (matrix metalloproteinase)-2, MMP-3 and MMP-9 levels in patients with acute coronary syndrome for death, readmission with HF (heart failure) or recurrent MI (myocardial infarction) and to compare them with established markers, NT-proBNP (N-terminal pro-B-type natriuretic peptide) and the GRACE (Global Registry of Acute Coronary Events) score. A single blood test was taken 4 days after admission in 1024 consecutive patients with acute MI with end points observed over 519 (134–1059) days [value is median (range)]. MMP-2 and MMP-3 were increased in patients who died (n=111) compared with survivors (P<0.006 and P=0.01 respectively), but were similar in patients with HF (n=106) or MI (n=138). MMP-9 levels were similar across study end points. Using Cox proportional hazards modelling, MMP-2 demonstrated an independent prediction of death [HR (hazard ratio) 6.60, P=0.001], along with NT-proBNP (HR 4.62, P<0.001) and the GRACE score (HR 1.03, P<0.001), but MMP-3, MMP-9 or log10-troponin I did not. For 1 year mortality, the areas under the receiver operating characteristic curves were 0.60 and 0.58 for MMP-2 and MMP-3 respectively, compared with 0.82 for NT-proBNP and 0.84 for the GRACE score (all P<0.001). Kaplan–Meier analysis revealed that MMP-2 levels in the top quartile were associated with higher mortality rates (log rank 12.49, P=0.006). On univariate analysis, MMP-2 and MMP-3 had a weak association with HF readmission, which was lost after adjustment for clinical factors. None of the MMPs tested predicted MI. In conclusion, this is the first single centre study that identifies MMP2 as an independent predictor of all-cause mortality post-ACS (acute coronary syndrome); however, NT-proBNP and the GRACE score are superior for risk stratification in this cohort.
A comparative study of Laplacians and Schrödinger– Lichnerowicz–Weitzenböck identities in Riemannian and antisymplectic geometry
Authors: Batalin Igor A. , Bering Klaus
Published: July 2009

We introduce an antisymplectic Dirac operator and antisymplectic gamma matrices. We explore similarities between, on one hand, the Schrödinger–Lichnerowicz formula for spinor bundles in Riemannian spin geometry, which contains a zeroth–order term proportional to the Levi–Civita scalar curvature, and, on the other hand, the nilpotent, Grassmann-odd, second-order Δ operator in antisymplectic geometry, which, in general, has a zeroth-order term proportional to the odd scalar curvature of an arbitrary antisymplectic and torsion-free connection that is compatible with the measure density. Finally, we discuss the close relationship with the two-loop scalar curvature term in the quantum Hamiltonian for a particle in a curved Riemannian space.
Reconnection in semicollisional, low-β plasmas
Authors: Schmidt S. , Günter S. , Lackner K.
Published: July 2009

Reconnection of semicollisional, low-β plasmas is studied numerically for two model problems using a two-field description of the plasma including electron pressure effects (and hence kinetic Alfvén-wave dynamics). The tearing unstable Harris sheet, with the global parameters of the Geospace Environment Modeling-challenge case, shows a linear growth of the peak reconnection rate with the drift parameter ρs when this scale is significantly larger than the resistive skin depth, and the island is smaller than the Harris sheet current layer width. As exemplary for a driven, rather than a spontaneous reconnection situation we study as second model system two coalescing islands, starting from a nonequilibrium situation. The peak reconnection rate again increases initially linearly with ρs but saturates and becomes ρs independent for larger values. In this saturated regime, no flux pileup occurs, and the reconnection is limited by the rate of approach of the two coalescing islands. The qualitative differences between spontaneous and driven reconnection cases and their scaling behavior are best understood by considering the reconnection rate as a triple product of outflow Mach number, outflow to inflow channel width ratio, and magnetic energy density at a height ρs above the X point.
Spectral functionals, nonholonomic Dirac operators, and noncommutative Ricci flows
Authors: Vacaru Sergiu I.
Published: July 2009

We formulate a noncommutative generalization of the Ricci flow theory in the framework of spectral action approach to noncommutative geometry. Grisha Perelman’s functionals are generated as commutative versions of certain spectral functionals defined by nonholonomic Dirac operators and corresponding spectral triples. We derive the formulas for spectral averaged energy and entropy functionals and state the conditions when such values describe (non)holonomic Riemannian configurations.
Anharmonic phonon transport in atomic wire coupled by thermal contacts with surface bond reconstruction
Authors: Li Jing , Au Yeung T. C. , Kam C. H. , Peng Yue , Chen Qing-hu , Zhao Xuean , Sun Chang Q.
Published: July 2009

Phonon transport in atomic wire coupled by two semi-infinite thermal contacts is investigated by atomic nonequilibrium Green’s functions. The effect on phonon transport due to anharmonicity in atomic wire and surface bond reconstruction of thermal contact is analyzed. It is found that surface bond reconstruction affects phonon transport significantly in the presence of anharmonicity.
Nonlinear interaction between ions and multiple electrostatic waves
Authors: Sheng Zheng-Mao , Yu Limin , Hao Guangzhou , White Roscoe
Published: July 2009

The nonlinear interaction of ions with multiple electrostatic waves propagating perpendicularly across a uniform magnetic field is investigated both analytically and numerically. Applying a multiscale expansion method with the wave amplitude as the perturbation parameter, a general nonlinear resonance condition is analytically derived. Under this condition, it is confirmed that multiple waves even below the cyclotron frequency and small amplitude are capable of effectively producing acceleration or stochastic heating by numerical simulation. Compared to the single wave situation, the stochastic threshold for heating by multiple waves with frequencies satisfied with a nonlinear resonance condition is significantly reduced because the nonlinear interaction of ions with multiple waves leads more easily to overlapping of islands and spreading of the stochastic layer in phase space. The above result is helpful to understand the energization mechanism of ions in the solar corona.
High-temperature ferroelectric phase transition observed in multiferroic Bi0.91La0.05Tb0.04FeO3
Authors: Jiang Q. H. , Liu F. T. , Nan Ce-Wen , Lin Yuan-Hua , Reece M. J. , Yan H. X. , Ning H. P. , Shen Z. J.
Published: July 2009

A single-phase Bi0.91La0.05Tb0.04FeO3 polycrystalline ceramic was fabricated by spark-plasma-sintering the precursor powder prepared by a sol-gel method. Temperature-dependent properties of polycrystalline Bi0.91La0.05Tb0.04FeO3 were characterized by x-ray diffraction, dielectric, and piezoelectric measurement. The x-ray diffraction results revealed a phase transition near 700 °C. Especially, temperature-dependent dielectric behavior demonstrated that there was a dielectric abnormal peak at about 697 °C, in addition to those two well-known dielectric abnormal peaks at 337 °C (Néel temperature) and 831 °C (Curie temperature). The observations, together with thermal depoled behavior, suggest a ferroelectric-ferroelectric phase transition from R3c to Pbnm at around 700 °C.
Rayleigh waves in air saturated axisymmetrical soft porous media
Authors: Allard J. F. , Dazel O. , Descheemaeker J. , Geebelen N. , Boeckx L. , Lauriks W.
Published: July 2009

Bulk waves in axisymmetrical poroelastic layers having a given slowness in a plane perpendicular to the symmetry axis of the medium have been previously studied. The previous works are generalized to any angle between the plane where the slowness is defined and the symmetry axis. This allows a description of the Rayleigh waves created by a line source on free surfaces which are not perpendicular to the symmetry axis. An illustration is provided with measurements on a glass wool of the speed of the Rayleigh wave performed in three perpendicular directions and the evaluation of the rigidity parameters of the fibrous medium.
Electromigration time to failure of SnAgCuNi solder joints
Authors: Basaran Cemal , Li Shidong , Hopkins Douglas C. , Veychard Damien
Published: July 2009

Electromigration time to failure and electrical resistivity of 95.5%Sn–1.5%Ag–0.5%Cu–0.03W%Ni microelectronics solder joints have been investigated experimentally. A Black-type electromigration time to failure equation is developed to describe the time to failure versus current density and temperature. It is observed that resistance of a solder joint is not just a function of the temperature but also a function of the current density. The activation energy over the range of 83–174°C is measured to be 0.77±0.12eV, and the current density exponent is found to be (8.60±1.65). It is also shown that the most commonly used Black’s electromigration time to failure equation cannot be used for solder joints.
Kramers-like turnover in load-dependent activated dynamics
Authors: Mondal Debasish , Ghosh Pulak Kumar , Ray Deb Shankar
Published: July 2009

Recent advancement of experimental techniques at the single molecule level has demonstrated how an external load affects a chemical reaction which controls the transport of biological motor proteins. Majority of these studies are concerned with thermodynamically open systems. We have examined a prototype model reaction in terms of inertial Brownian motion of a particle in a force field subjected to an overdamped motion of a viscous load coupled harmonically to the particle. A general analytical expression for the rate constant has been derived to demonstrate that depending on the strength of harmonic coupling and drag coefficient of the load a Kramers-like turnover can be realized in the spatial diffusion-limited regime. The turnover reduces to a crossover between the two states characterized by zero-load and finite load conditions.
Microcrystalline Si films grown at low temperatures (90–220 °C) with high rates in atmospheric-pressure VHF plasma
Authors: Kakiuchi Hiroaki , Ohmi Hiromasa , Ouchi Kentaro , Tabuchi Keita , Yasutake Kiyoshi
Published: July 2009

This work deals with the structural properties of microcrystalline silicon (μc-Si:H) films grown at low temperatures (90–220 °C) with high rates in atmospheric-pressure He/H2/SiH4 plasma, which is excited by a 150 MHz very high frequency power using a porous carbon electrode. This plasma permits to enhance the chemical reactions both in gas phase and on the film-growing surface, while suppressing ion impingement upon the surface. Raman crystalline volume fractions of the μc-Si:H films are studied in detail as functions of film thickness and substrate temperature (Tsub). The results show that the μc-Si:H film deposited with 50 (SCCM) (SCCM denotes standard cubic centimeters per minute at STP) SiH4 has no amorphous transition layers at the film/substrate interface in spite of the high deposition rate of 6.4 nm/s, which is verified by the cross sectional observations with a transmission electron microscope. In addition, the Tsub dependence of Raman crystallinity of the μc-Si:H films indicates that a highly crystallized μc-Si:H film grows even when Tsub is reduced to 90 °C. Further systematic studies are needed for both device applications and deposition on thermally sensitive plastic materials.
Luminescent properties of Pr3+-sensitized LaPO4:Gd3+ ultraviolet-B phosphor under vacuum-ultraviolet light excitation
Authors: Okamoto Shinji , Uchino Rika , Kobayashi Keisuke , Yamamoto Hajime
Published: July 2009

Luminescent properties of Pr3+-sensitized LaPO4:Gd3+ under vacuum-ultraviolet (vuv) light excitation have been investigated. The energy transfer probably occurs from the 5d levels in Pr3+ ions to Gd3+ ions under 172nm light excitation. LaPO4:Gd3+,Pr3+ shows efficient ultraviolet-B (uv-B) emission at 312nm, whose peak intensity reaches its maximum at Gd=35mol% and Pr=5mol%. (La0.65Gd0.35)0.95Pr0.05PO4 is about 1.6 times higher than a typical uv-B phosphor for vuv lamp, Y0.75Gd0.25Al3(BO3)4, in Gd3+-emission intensity under 172nm light excitation. This result implies that the Pr3+-sensitized LaPO4:Gd3+ is a candidate of uv-B phosphors for xenon-excimer discharge vuv lamps. In order to evaluate the effect of the narrow-band uv-B emission by LaPO4:Gd3+,Pr3+ phosphor, irradiation test on DNA was performed. The irradiation damage of pUC 18 DNA by the narrow-band uv-B light from the LaPO4:Gd3+,Pr3+ phosphor is in the same magnitude as that by uv-A light from a filtered Hg lamp, even though the uv-B lamp is higher than the uv-A lamp in power density and photon energy.
White light generation from Dy3+-doped ZnO–B2O3–P2O5 glasses
Authors: Jayasimhadri M. , Jang Kiwan , Lee Ho Sueb , Chen Baojiu , Yi Soung-Soo , Jeong Jung-Hyun
Published: July 2009

Dysprosium doped ZnO–B2O3–P2O5 (ZBP) glasses were prepared by a conventional melt quenching technique in order to study the luminescent properties and their utility for white light emitting diodes (LEDs). X-ray diffraction spectra revealed the amorphous nature of the glass sample. The present glasses were characterized by infrared and Raman spectra to evaluate the vibrational features of the samples. The emission and excitation spectra were reported for the ZBP glasses. Strong blue (484 nm) and yellow (574 nm) emission bands were observed upon various excitations. These two emissions correspond to the F49/2→H615/2 and F49/2→H613/2 transitions of Dy3+ ions, respectively. Combination of these blue and yellow bands gives white light to the naked eye. First time, it was found that ZnO–B2O3–P2O5 glasses efficiently emit white light under 400 and 454 nm excitations, which are nearly match with the emissions of commercial GaN blue LEDs and InGaN LED, respectively. CIE chromaticity coordinates also calculated for Dy3+: ZBP glasses to evaluate the white light emission.
Electronic structure of poly(azomethine) thin films
Authors: Weszka Jan , Bednarski Henryk , Domański Marian
Published: July 2009

Poly(1,4–phenylene-methylidynenitrilo-1,4–phenylenenitrilomethylidyne) (PPI) backbone approximated with poly(p-phenylene vinylene)like polymer composed of alternate phenylene and vinylenelike units is treated within π electron approximation in terms of the chain composed of united atoms built up of virtual benzene and ethylene atoms. Electronic structure of the united atom is derived from interactions of benzene p and β bands with V band of ethylene, taking into account that continuity of their π systems results from overlap of vinylenelike highest occupied molecular orbital and lowest unoccupied molecular orbital orbitals with relevant components of benzene molecular orbitals having phase at parapositions. Electronic band structure has been derived within π-electron approximation in a way resembling tight binding approximation usually applied to semiconductors. The proposed model is suitable to interpret UV-visible spectra of PPI with additional explaining vibronic progressions. Additionally, an expected location of lone pair related level is proposed.
Lumpers or splitters? Evaluating recovery and management plans for metapopulations of herring
Authors: Kell Laurence T. , Dickey-Collas Mark , Hintzen Niels T. , Nash Richard D. M. , Pilling Graham M. , Roel Beatriz A.
Published: July 2009

Kell, L. T., Dickey-Collas, M., Hintzen, N. T., Nash, R. D. M., Pilling, G. M., and Roel, B. A. 2009. Lumpers or splitters? Evaluating recovery and management plans for metapopulations of herring. – ICES Journal of Marine Science, 66: 1776–1783. The long-term management of a stock representing a metapopulation has been simulated in a case study loosely based upon herring to the west of the British isles, where stocks are currently assessed and managed by management area, although there is evidence of mixing between stocks (in terms of connectivity, migrations, and exploitation). The simulations evaluate scientific advice (based on virtual population analysis, VPA) and the sustainability of fishing under two population-structure scenarios, corresponding either to discrete stocks, which only mix on the feeding grounds, or where diffusion between stocks takes place. The ability of stock assessment to monitor stock status and exploitation levels was evaluated for defining stocks based on fishing areas and for stocks that combined fishing areas. The study showed that assessment based on VPA of the metapopulation could fail to detect overexploitation of stocks and fail to detect and distinguish between the effects of exploitation and regime shifts.
Estimating von Bertalanffy growth parameters from growth increment data using a linear mixed-effects model, with an application to the sea scallop Placopecten magellanicus
Authors: Hart Deborah R. , Chute Antonie S.
Published: July 2009

Hart, D. R., and Chute, A. S. 2009. Estimating von Bertalanffy growth parameters from growth increment data using a linear mixed-effects model, with an application to the sea scallop Placopecten magellanicus. – ICES Journal of Marine Science, 66: 2165–2175. We introduce a novel linear mixed-effects method for estimating von Bertalanffy growth parameters from growth increment data that lack explicit age information. The method is simple to implement and can incorporate and estimate variability in both the asymptotic size L∞ and the Brody growth coefficient K. Simulations indicate that estimates from the method are accurate over a range of conditions. The method is applied to growth data from more than 6000 Atlantic sea scallop (Placopecten magellanicus) shells from the Mid-Atlantic Bight and Georges Bank. Sea scallops grow to a larger asymptotic shell height on Georges Bank than on the Mid-Atlantic Bight and in areas closed to fishing on Georges Bank than on the fished portions. Depth and latitude had significant effects on scallop growth in both the Mid-Atlantic and Georges Bank, with smaller asymptotic shell heights in deeper water and at higher latitudes.
The YAP1 Homolog–Mediated Oxidative Stress Tolerance Is Crucial for Pathogenicity of the Necrotrophic Fungus Alternaria alternata in Citrus
Authors: Lin Ching-Hsuan , Yang Siwy Ling , Chung Kuang-Ren
Published: July 2009

Citrus brown spot disease is caused by the necrotrophic fungus Alternaria alternata. Its pathogenic capability has been thought to depend exclusively on the production of host-selective ACT toxin. However, circumvention of plant defenses is also likely to be important for the disease process. To investigate the fungal response to host-generated reactive oxygen species (ROS), we cloned and characterized the AaAP1 gene of A. alternata, which encodes a polypeptide resembling yeast YAP1-like transcriptional activators implicated in cellular responses to stress. Expression of the AaAP1 gene in a wild-type strain was primarily induced by H2O2 or ROS-generating oxidants. Using a loss-of-function mutation in the AaAP1 gene, we demonstrated an essential requirement for oxidative tolerance during the host invasion step. Mutants lacking AaAP1 showed increased sensitivity to H2O2 and loss of fungal pathogenicity. The ΔAaAP1 null mutant did not cause any visible necrotic lesions on wounded or unwounded leaves of citrus cv. Minneola. Compared with the wild type, the null mutant displayed lower catalase, peroxidase, and superoxide dismutase activities. All mutant phenotypes were restored to the wild type in fungal strains expressing a functional copy of AaAP1. Upon exposure to H2O2, the AaAP1::sGFP (synthetic green fluorescent protein) fusion protein became localized in the nucleus. Inoculation of the mutant with NADPH oxidase inhibitors partially restored fungal pathogenicity. Our results highlight the global regulatory role of a YAP1 homolog in response to oxidative stress in A. alternata and provide insights into the critical role of ROS detoxification in the pathogenicity of A. alternata.
Are Grapevine Stomata Involved in the Elicitor-Induced Protection Against Downy Mildew?
Authors: Allègre Mathilde , Héloir Marie-Claire , Trouvelot Sophie , Daire Xavier , Pugin Alain , Wendehenne D. , Adrian Marielle
Published: July 2009

Stomata, natural pores bordered by guard cells, regulate transpiration and gas exchanges between plant leaves and the atmosphere. These natural openings also constitute a way of penetration for microorganisms. In plants, the perception of potentially pathogenic microorganisms or elicitors of defense reactions induces a cascade of events, including H2O2 production, that allows the activation of defense genes, leading to defense reactions. Similar signaling events occur in guard cells in response to the perception of abscisic acid (ABA), leading to stomatal closure. Moreover, few elicitors were reported to induce stomatal closure in Arabidopsis and Vicia faba leaves. Because responses to ABA and elicitors share common signaling events, it led us to question whether stomatal movements and H2O2 production in guard cells could play a key role in elicitor-induced protection against pathogens that use stomata for infection. This study was performed using the grapevine–Plasmopara viticola pathosystem. Using epidermal peels, we showed that, as for ABA, the elicitor-induced stomatal closure is mediated by reactive oxygen species (ROS) production in guard cells. In plants, we observed that the protection against downy mildew induced by some elicitors is probably not due only to effects on stomatal movements or to a guard-cell-specific activation of ROS production.
First Report of Citrus bent leaf viroid and Citrus dwarfing viroid from Citrus in Punjab, Pakistan
Authors: Cao M. J. , Atta S. , Liu Y. Q. , Wang X. F. , Zhou C. Y. , Mustafa A. , Iftikhar Y.
Published: July 2009

Pakistan is among the top 10 citrus-producing countries of the world and the leader in Kinnow mandarin production with production concentrated in the province of Punjab, which produces more than 96% of the total citrus crop. To evaluate the presence and distribution of citrus viroids in this area, 34 samples were collected in September 2008 from citrus orchards in the Sargodha, Bhalwal, and Faisalabad areas of Punjab, including 15 ‘Mosambi’ and two ‘Bloodred’ sweet oranges (Citrus sinensis), eight ‘Kinnow’ and four ‘Feutrell Early’ mandarins (C. reticulata), three ‘Jatti Khatti’ rough lemon (C. jambhiri), and two grapefruit (C. paradisi), which showed stunting, bark scaling, and cracking symptoms on the rootstock which was either citrange (Poncirus trifoliata × C. sinensis) or sweet lime (C. limetta). Infected budwood from these trees was grafted onto indicator plants of Arizona 861-S-1 ‘Etrog citron’ (C. medica) budded on rough lemon rootstock, and after 3 months, the citron showed typical viroid symptoms of mild epinasty and leaf roll with 23 of the 34 samples. A one-step multiplex reverse transcription (RT)-PCR assay (3) was used to detect simultaneously Citrus exocortis viroid (CEVd), Citrus bent leaf viroid (CBLVd), Hop stunt viroid (HSVd), Citrus dwarfing viroid (CDVd), and Citrus bark cracking viroid (CBCVd). On the basis of amplification of the appropriately sized DNA, CEVd, CBLVd, HSVd, and CDVd were detected in 12, 8, 31, and 17 samples, respectively, whereas CBCVd was not detected. Twenty-three of 34 infected samples harbored more than one viroid species and one had four viroids. Budwood from 11 trees did not induce viroid symptoms on Etrog citron. Two of these trees were infected with CBLVd only and nine with HSVd only. Four primer pairs were used to amplify the full sequences of CEVd, CBLVd, HSVd, and CDVd by RT-PCR (2), which were cloned by standard methods. Sequences of three cDNA clones each of CEVd (Nos. FJ773253, FJ773254, and FJ773255), CBLVd (Nos. FJ773262, FJ773263, and FJ773267), HSVd (Nos. FJ773268, FJ773269, and FJ773271), and CDVd (Nos. FJ773274, FJ773275, and FJ773276) were deposited in GenBank. BLAST analysis showed that these nucleotide sequences had greater than 97% nucleotide identity to the most similar genome sequences in GenBank. One of the HSVd sequences, FJ773271, presented the cachexia determinants. To our knowledge, this is the first report of CBLVd and CDVd in Pakistan (1). These results indicate the need for proper indexing of mother trees and a virus-free propagation scheme to create healthy budwood sources in Pakistan.

References: (1) M. Arif et al. Pak. J. Bot. 37:407, 2005. (2) L. Bernard and N. Duran-Vila. Mol. Cell. Probes 20:105, 2006. (3) X. F. Wang et al. Eur. J. Plant. Pathol, 124:175, 2009.
Herbivore release through cascading risk effects
Authors: Schmidt-Entling Martin H. , Siegenthaler Eva
Published: July 2009

Predators influence prey through consumption, and through trait-mediated effects such as emigration in response to predation risk (risk effects). We studied top-down effects of (sub-) adult wolf spiders (Lycosidae) on arthropods in a meadow. We compared risk effects with the overall top-down effect (including consumption) by gluing the chelicers of wolf spiders to prevent them from killing the prey. In a field experiment, we created three treatments that included either: (i) intact (‘predation’) wolf spiders; (ii) wolf spiders with glued chelicers (‘risk spiders’); or (iii) no (sub-) adult wolf spiders. Young wolf spiders were reduced by their (sub-) adult congeners. Densities of sheetweb spiders (Linyphiidae), a known intraguild prey of wolf spiders, were equally reduced by the presence of risk and predation wolf spiders. Plant- and leafhoppers (Auchenorrhyncha) showed the inverse pattern of higher densities in the presence of both risk and predation wolf spiders. We conclude that (sub-) adult wolf spiders acted as top predators, which reduced densities of intermediate predators and thereby enhanced herbivores. Complementary to earlier studies that found trait-mediated herbivore suppression, our results demonstrate that herbivores can be enhanced through cascading risk effects by top predators.
F
ordisc
and the determination of ancestry from cranial measurements
Authors: Elliott Marina , Collard Mark
Published: July 2009

Determining the ancestry of unidentified human remains is a major task for bioarchaeologists and forensic anthropologists. Here, we report an assessment of the computer program that has become the main tool for accomplishing this task. Called F
ordisc
, the program determines ancestry through discriminant function analysis of cranial measurements. We evaluated the utility of F
ordisc
with 200 specimens of known ancestry. We ran the analyses with and without the test specimen's source population included in the program's reference sample, and with and without specifying the sex of the test specimen. We also controlled for the possibility that the number of variables employed affects the program's ability to attribute ancestry. The results of the analyses suggest that F
ordisc
's utility in research and medico-legal contexts is limited. F
ordisc
will only return a correct ancestry attribution when an unidentified specimen is more or less complete, and belongs to one of the populations represented in the program's reference samples. Even then F
ordisc
can be expected to classify no more than 1 per cent of specimens with confidence.
How sea lice from salmon farms may cause wild salmonid declines in Europe and North America and be a threat to fishes elsewhere
Authors: Costello Mark J.
Published: July 2009

Fishes farmed in sea pens may become infested by parasites from wild fishes and in turn become point sources for parasites. Sea lice, copepods of the family Caligidae, are the best-studied example of this risk. Sea lice are the most significant parasitic pathogen in salmon farming in Europe and the Americas, are estimated to cost the world industry €300 million a year and may also be pathogenic to wild fishes under natural conditions.

Epizootics, characteristically dominated by juvenile (copepodite and chalimus) stages, have repeatedly occurred on juvenile wild salmonids in areas where farms have sea lice infestations, but have not been recorded elsewhere. This paper synthesizes the literature, including modelling studies, to provide an understanding of how one species, the salmon louse,
Lepeophtheirus salmonis
, can infest wild salmonids from farm sources. Three-dimensional hydrographic models predicted the distribution of the planktonic salmon lice larvae best when they accounted for wind-driven surface currents and larval behaviour.
Caligus
species can also cause problems on farms and transfer from farms to wild fishes, and this genus is cosmopolitan. Sea lice thus threaten finfish farming worldwide, but with the possible exception of
L. salmonis
, their host relationships and transmission adaptations are unknown. The increasing evidence that lice from farms can be a significant cause of mortality on nearby wild fish populations provides an additional challenge to controlling lice on the farms and also raises conservation, economic and political issues about how to balance aquaculture and fisheries resource management.
Influence of sexual selection and feeding functional morphology on diversification rate of parrotfishes (Scaridae)
Authors: Kazancıoğlu Erem , Near Thomas J. , Hanel Reinhold , Wainwright Peter C.
Published: July 2009

Scaridae (parrotfishes) is a prominent clade of 96 species that shape coral reef communities worldwide through their actions as grazing herbivores. Phylogenetically nested within Labridae, the profound ecological impact and high species richness of parrotfishes suggest that their diversification and ecological success may be linked. Here, we ask whether parrotfish evolution is characterized by a significant burst of lineage diversification and whether parrotfish diversity is shaped more strongly by sexual selection or modifications of the feeding mechanism. We first examined scarid diversification within the greater context of labrid diversity. We used a supermatrix approach for 252 species to propose the most extensive phylogenetic hypothesis of Labridae to date, and time-calibrated the phylogeny with fossil and biogeographical data. Using divergence date estimates, we find that several parrotfish clades exhibit the highest diversification rates among all labrid lineages. Furthermore, we pinpoint a rate shift at the shared ancestor of
Scarus
and
Chlorurus
, a scarid subclade characterized by territorial behaviour and strong sexual dichromatism, suggesting that sexual selection was a major factor in parrotfish diversification. Modifications of the pharyngeal and oral jaws that happened earlier in parrotfish evolution may have contributed to this diversity by establishing parrotfishes as uniquely capable reef herbivores.
Null Mutation of the MdACS3 Gene, Coding for a Ripening-Specific 1-Aminocyclopropane-1-Carboxylate Synthase, Leads to Long Shelf Life in Apple Fruit
Authors: Wang Aide , Yamakake Junko , Kudo Hisayuki , Wakasa Yuhya , Hatsuyama Yoshimichi , Igarashi Megumi , Kasai Atsushi , Li Tianzhong , Harada Takeo
Published: July 2009

Expression of MdACS1, coding for 1-aminocyclopropane-1-carboxylate synthase (ACS), parallels the level of ethylene production in ripening apple (Malus domestica) fruit. Here we show that expression of another ripening-specific ACS gene (MdACS3) precedes the initiation of MdACS1 expression by approximately 3 weeks; MdACS3 expression then gradually decreases as MdACS1 expression increases. Because MdACS3 expression continues in ripening fruit treated with 1-methylcyclopropene, its transcription appears to be regulated by a negative feedback mechanism. Three genes in the MdACS3 family (a, b, and c) were isolated from a genomic library, but two of them (MdACS3b and MdACS3c) possess a 333-bp transposon-like insertion in their 5′ flanking region that may prevent transcription of these genes during ripening. A single nucleotide polymorphism in the coding region of MdACS3a results in an amino acid substitution (glycine-289 → valine) in the active site that inactivates the enzyme. Furthermore, another null allele of MdACS3a, Mdacs3a, showing no ability to be transcribed, was found by DNA sequencing. Apple cultivars homozygous or heterozygous for both null allelotypes showed no or very low expression of ripening-related genes and maintained fruit firmness. These results suggest that MdACS3a plays a crucial role in regulation of fruit ripening in apple, and is a possible determinant of ethylene production and shelf life in apple fruit.
Global Colleagues: The Slovene Ethnological Society: Research, Professions and Publications
Authors: Ramšak Mojca
Published: July 2009

In Europe, social anthropology evolved from its roots in folkloric and ethnographic representation to broader comparative ethnological approaches in the second half of the 20th century. In “Anthropologists and Native Ethnographers in Central European Villages” (Current Anthropology Vol 9:311‐15), Thomas Hofer compared North American and Western European ethnologists with Eastern European ethnologists. He concluded that the former often view Eastern European ethnologists as “underdeveloped anthropologists,” while the latter are amazed at the willingness of American and Western European anthropologists to investigate themes too familiar to merit investigation. The distinction between ethnographers and ethnologists still is more likely to be found in Eastern Europe than in the West, where ethnography is merged as a stage in the production of ethnological comparisons and theory. When the two become institutionalized as separate disciplines, there can develop a hostile battlefield in which the complementarity of ethnographic research is submerged or even lost in ethnological theory. This evolution can be seen in the Slovene case, described here by Mojca Ramšk. —June Nash (CUNY), Global Colleagues Contributing Editor
HUMAN RIGHTS FORUM
Authors: Chernela Janet , Martinez Samuel , Kimmerle Erin H
Published: July 2009

In 2002, the AAA Committee for Human Rights (CfHR) initiated the Fellows Program in the Anthropology of Human Rights. Positions provide recipients with strong experience in human rights work, possibilities for publication, as well as the opportunity to work closely with the Committee, government agencies, and human rights‐based NGOs. CfHR Research Fellow (2002–2003) Kimmerle came to the position with a strong background in the practice of anthropology in international human rights. Between 2000 and 2001 she served on the forensic team of the International Criminal Tribunal for the former Yugoslavia in its missions in Bosnia‐Herzegovina and Croatia. We are pleased to present here a brief version of Kimmerle's report. A longer version appears on the Human Rights page of the AAA website (http:www.aaanet.org).