bluuebunny/crossref_metadata_2025 huggingface dataset:
Life-history strategy in Typhula incarnata and T. ishikariensis biotypes A, B, and C as determined by sclerotium production
Authors: Matsumoto Naoyuki , Tajimi Akitoshi
Published: March 2010

The life-history strategies of Typhula incarnata and T. ishikariensis, the snow mold fungi, were studied in culture experiments. Radial mycelial growth at 0 °C, a temperature at which they thrive under natural conditions, was about half that of growth at the near-optimal temperature, 10 °C. However, when the colonies were covered with unsterile soil, mycelial growth at 0 °C was much greater than at 10 °C. Sclerotium production by T. incarnata was rapid in the latter half of the culture period, and sclerotium maturation was promoted by selected fungi. Typhula incarnata produced sclerotia frequently along the junction with colonies of selected fungi. Typhula ishikariensis biotype A produced the highest percent sclerotial biomass. Sclerotium maturation, i.e., pigmentation, was not stimulated by the selected fungi, but sclerotium production was moderately frequent in dual cultures with them. Typhula ishikariensis biotypes B and C produced the lowest percent sclerotial biomass. Their sclerotium maturation was rapid but not stimulated by the selected fungi. These findings suggest that although these snow mold fungi are, as a whole, stress tolerant, T. incarnata is relatively ruderal, T. ishikariensis biotype A is typically stress tolerant, and T. ishikariensis biotypes B and C are adapted to habitats with high stress and high disturbance.
Host cell responses in susceptible hard pine tissue infected with Endocronartium harknessii
Authors: Hopkin A. A. , Reid J.
Published: March 2010

Compatible interactions between susceptible hypocotyl tissue of Pinus banksiana Lamb, and Endocronartium harknessii (J. P. Moore) Y. Hirat. were studied using light and transmission electron microscopy. Host endoplasmic reticulum was observed to be closely associated with the haustorial body, although staining with silver proteinate failed to show any similarity between the contents of the endoplasmic reticulum and extrahaustorial matrix. The haustorium was also commonly observed to be closely associated with the host nucleus, often indenting the latter, though never in direct contact. Chloroplasts in recently infected cells appeared similar to those in uninfected cells, but in more advanced infections large starch grains were observed in the chloroplasts of the outer cortex; such chloroplasts normally contained little starch. Collars were another common feature of infected cells. Collars were continuous with the host cell wall and reacted to silver proteinate in a similar manner to the cell wall; callose was not evident. Collars were associated with portions of the cell wall that were inwardly displaced by the fungus; however, cytoplasmic vesicles were also observed in association with the collar and possibly contributed to their development.
Contribution toward a monograph of the genus Ascosphaera
Authors: Bissett John
Published: March 2010

Cultures and herbarium collections of the previously described species of Ascosphaera were studied. Additional observations are reported on Ascosphaera strains associated with the alfalfa leaf-cutting bee, Megachile rotundata (Fab.). Three new species of Ascosphaera are described, all occurring in brood cells of the alfalfa leaf-cutting bee. Ascosphaera larvis sp.nov., with short, ellipsoidal ascospores, was frequently associated with a chalkbrood-like disease in early-instar larvae. Ascosphaera pollenicola sp.nov., a homothallic species with subcylindric ascospores, most often occurred on pollen provisions in brood cells. Ascosphaera variegata sp.nov., with conspicuously mottled ascomatal walls, was isolated from pollen and also from larvae that had died from undetermined causes. Descriptions and an identification key are provided for the 11 species of Ascosphaera currently recognized.
A systematic evaluation of basidiospore symmetry and tegumentation in hypogeous and gasteroid Russulales
Authors: Miller Steven L.
Published: March 2010

Spore wall architecture and ontogeny of ornamentation in several genera and species of hypogeous and gasteroid Russulales are similar to those described previously for agaricoid Lactarius lignyotellus. Spore walls are composed of four layers, each differing in thickness and electron density. Layer 2 is electron transparent and corresponds to a dark blue, amyloid layer when mounted in Melzer's iodine reagent and viewed with the light microscope. Establishment of spore symmetry may be regulated by the hilar appendix body, which is a poorly differentiated cytoplasmic region in the hilar appendix of asymmetric spores of Macowanites luteolus, Elasmomyces russuloides, and Zelleromyces versicaulus but which is absent in symmetric spores of Z. sculptisporus, Martellia subochracea, and Gymnomyces yubaensis. A continuum in spore morphology from truly symmetric to asymmetric is evident in spores from individual sporocarps of many species of the Russulales. The variation in spore symmetry and spore surface ornamentation has clouded taxonomic concepts in the Russulales. Systematically, development of orthotropic and heterotropic spores has been regarded as two distinct end points of evolution, when they are likely terms describing degrees of the same phenomenon. The current circumscription of families and genera in the Russulales based on spore symmetry, therefore, appears to be artificial.
Adventitious rooting of four Salicaceae species in response to a flooding event
Authors: Krasny Marianne E. , Zasada John C. , Vogt Kristiina A.
Published: March 2010

The ability to form adventitious roots in response to a flooding event was examined in three floodplain species, sandbar willow (Salix interior Rowlee), feltleaf willow (Salix alaxensis (Anderss.) Cov.), and balsam poplar (Populus balsamifera L.), and one upland species, trembling aspen (Populus tremuloides Michx.), in interior Alaska. The mean number of adventitious roots formed per seedling was 7, 5, 2, and 0 for sandbar willow, feltleaf willow, balsam poplar, and trembling aspen, respectively. The ability to form adventitious roots was related to the distribution of the species on the floodplain.
Community organization: recent advances in numerical methods
Authors: Orlóci László
Published: March 2010

"Recent" in the title signifies a time period of over three decades. This period begins with John von Neumann's original work on computer logic, John Curtis' and David Goodall's on numerical phytosociology, and Eugene Odum's on systems ecology. It culminates in the advent of the microcomputer and the wide use of computer techniques. Within the noted time span, the methodological advances are closely linked with (i) developments in hardware and software technology and (ii) historical changes in ecological thought and community theory. An advance is considered as any methodological invention, or any change in a method's design, that brings the analysis into closer conformity with the relevant community theory and improves method efficiency and practical admissibility. Developments in specific fields of vegetation analysis are reviewed.
Community organization: methods of study and prediction of the productivity and yield of forest ecosystems
Authors: Kimmins J. P.
Published: March 2010

Increasing demands for forest products and for nonproductive land uses from a diminishing forest land base will require a much improved understanding of, and ability to predict, forest productivity if all the competing needs are to be satisfied in the future. The history of forest productivity and yield studies is reviewed briefly, and the limitations of various methods of measuring forest biomass and production are discussed. Attention is drawn to the importance of understanding the allocation of net production to different biomass components, and the dynamics of small and fine roots. Three major approaches to the prediction of forest productivity and yield have developed since the beginning of the 19th century: (i) a "historical-bioassay" approach that has been used throughout the history of forest yield research; (ii) a production process approach initiated in the mid-19th century; and (iii) a more recent hybrid approach that combines the first two approaches. These three methodologies broadly reflect three different approaches to the study of production and yield; an empirically based population approach, a process-based autecological (ecophysiological) approach, and an ecosystem approach, respectively. An example of an ecosystem-level hybrid simulation model of forest production, FORCYTE-11, is described briefly.
ON COMPLETE SPACELIKE HYPERSURFACES WITH CONSTANT m-TH MEAN CURVATURE IN AN ANTI-DE SITTER SPACE
Authors: WU B. Y.
Published: March 2010

We investigate complete spacelike hypersurfaces in an Anti-de Sitter space with constant m-th mean curvature and two distinct principal curvatures. By using Otsuki's idea, we obtain some global classification results. For their application, we obtain some characterizations for hyperbolic cylinders. We prove that the only complete spacelike hypersurfaces in Anti-de Sitter (n + 1)-spaces (n ≥ 3) of constant mean curvature or constant scalar curvature with two distinct principal curvatures λ and μ satisfying inf (λ - μ)2 > 0 are the hyperbolic cylinders. It is a little surprising that the corresponding result does not hold for m-th mean curvature when m > 2. We also obtain some global rigidity results for hyperbolic cylinders in terms of square length of the second fundamental form.
TS-LIKE GRAVITATIONAL WAVES IN 4D EINSTEIN GRAVITY
Authors: WEI YI-HUAN
Published: March 2010

We propose TS-like class of gravitational wave solutions in 4D Einstein gravity. TS1-like gravitational wave solution is analyzed in detail. On the axis, the gauge potential changes from a finite value to zero at t = τ. The spacetime on the axis approaches the flat one as t → ∞. It is found that by an appropriate parameter substitution and coordinate transformation TS-like gravitational wave solutions in 4D Einstein gravity may be obtained from TS solutions.
LOCALIZATION OF MATTERS ON A NON-Z2-SYMMETRIC THICK BRANE
Authors: LIANG JUN , DUAN YI-SHI
Published: March 2010

We study localization of various matter fields on a non-Z2-symmetric scalar thick brane in a pure geometric Weyl integrable manifold in which variations in the length of vectors during parallel transport are allowed and a geometric scalar field is involved in its formulation. It is shown that, for spin 0 scalar field, the massless zero mode can be normalized on the brane. Spin 1 vector field cannot be normalized on the brane. And there is no spinor field which can be trapped on the brane for the case of no Yukawa-type coupling. By introducing the appropriate Yukawa coupling, the left or right chiral fermionic zero mode can be localized on the brane.
DENSITY FUNCTIONAL STUDY OF STRUCTURE AND STABILITY OF Al7OH CLUSTERS
Authors: LU Q. L. , HE J. , LUO Q. Q. , WAN J. G. , WANG G. H.
Published: March 2010

We studied the structure and electronic properties of Al 7 OH clusters using density functional theory with generalized gradient approximation. OH prefers to the ontop site of Al atoms, and the hollow form is not stable. The Al 7 moieties can keep their structures in ontop form Al 7 OH cluster, while it dramatically changes for bridge form ones. The binding strength between Al 7 and OH are much larger than that of Al 7 I and Al 7 H . The bonding characteristic of Al 7– OH is mainly ionic according to the population analysis. Large binding energy, HOMO–LUMO gap, and high ionization potential imply that Al 7 OH cluster is physically high and chemically stable.
ON THE EQUIVALENCE OF THE BINDING ENERGY OF A COOPER PAIR AND THE BCS ENERGY GAP: A FRAMEWORK FOR DEALING WITH COMPOSITE SUPERCONDUCTORS
Authors: MALIK G. P.
Published: March 2010

Employing the Bethe–Salpeter equation (BSE) and the Matsubara recipe, and invoking both the electron–electron and the hole–hole scattering channels, we establish that the binding energy (W) of a Cooper pair (CP) is real, and equals the BCS energy gap (Δ) for all T ≤ Tc for a one-component superconductor. Given that the BCS theory is a generalization of the Hartree–Fock theory (generalized to allow for particle number fluctuations), the cognescenti would expect this result as a direct consequence of Koopman's theorem, proved for and well-known in the latter theory. However, this theorem is seldom mentioned in the literature on superconductivity; on the contrary, there is the statement in well-known texts that the binding energy of a CP becomes imaginary when the above-stated scattering channels are invoked for their formation. The importance of |W| = |Δ| for high-Tc superconductors is brought out by replacing the one-particle propagator in the BSE by a superpropagator — a field-theoretic construct apt for dealing with composite superconductors (CSs). A set of generalized BCS equations is thus obtained which, with the input of the multiple gaps of a CS, enables one to calculate its Tc uniquely. Applications of these equations will be taken up in a subsequent paper.
ELECTRON-PHONON COUPLING IN GRAPHENE
Authors: MILOŠEVIĆ IVANKA , KEPČIJA NENAD , DOBARDŽIĆ EDIB , DAMNJANOVIĆ MILAN , MOHR MARCEL , MAULTZSCH JANINA , THOMSEN CHRISTIAN
Published: March 2010

Numerical and symmetry based analysis of the electron-phonon coupling in graphene have been performed. Symmetry alone predicts the Kohn anomalies, their positions in the Brillouin zone and all quantum numbers of the Kohn modes and the vectors of the Kohn displacements. Dispersion of kink phonons is calculated and found to be similar to the classical phonon spectrum. Interestingly, most of the Γ (including all the acoustic phonons as well) and K modes are shown to be uncoupled to electrons.
SHORT-CIRCUIT OXYGEN DIFFUSION IN THERMALLY GROWN SILICA LAYER
Authors: GLIGORIJEVIĆ BOJAN , SCHMIDT HARALD , RADOVIĆ NENAD , DAVIDOVIĆ MILORAD , KUTIN MARINA , JANIĆIJEVIĆ ACO
Published: March 2010

Amorphous polymer-derived Si - C - N ceramics can be doped with different elements ( Al , B etc.) through various pre-ceramic polymer routes. Thus, controlling of the high temperature oxidation resistance can be achieved on an atomic level. An important factor for silica layer growth is oxygen diffusion in protective thermally grown layers. In order to get insight of the oxygen diffusion mechanism, analysis should include both, bulk and short-circuit diffusion. XRD measurements of oxidized Si - C - N and SiC revealed the possibility that oxide layers were fully crystallized and are composed of nano-sized cristobalite-like grains. Secondary ion mass spectrometry depth profile analysis after 18 O 2-16 O 2 isotope exchange experiments on oxidized SiC indicated that short-circuit diffusion is probably grain boundary diffusion of molecular oxygen.
PHYSICOCHEMICAL TRANSFORMATIONS OF ALUMINUM AND QUARTZ POWDERS MIXTURE UNDER LOADING BY SPHERICAL CONVERGING SHOCK WAVES
Authors: TALUTS N. I. , DOBROMYSLOV A. V. , KOZLOV E. A.
Published: March 2010

The phase composition and structure of a mixture of aluminum and quartz powders taken in a ratio of 1:1 have been studied after loading by spherical converging shock waves. A number of concentric layers (zones) have been observed in the sample after shock-wave loading. The presence of several zones in the sample reflects the specific features of the processes occurring in different pressure ranges. It has been established that pressures below ~45 GPa cause only additional compacting of the material and deformation of aluminum and quartz. In this case, the quartz grain size substantially decreases up to the transition into the X-ray amorphous state. The attainment of a pressure of ~45 GPa initiates the solid-state reaction of SiO 2 decomposition, which leads to the precipitation of pure silicon and the evolution of oxygen. The beginning of the silicon precipitation and the chemical reaction of Al 2 O 3 formation are separated over the pressure scale. The critical pressure, which is necessary for the solid-state chemical reaction of the Al 2 O 3 formation, is about 50 GPa.
MECHANICAL PROPERTIES OF P/M MATERIALS OF RAPIDLY SOLIDIFIED Al-Co-Mg ALLOYS AT ELEVATED TEMPERATURES
Authors: SUGAMATA MAKOTO , OHKI
Published: March 2010

With an aim of obtaining aluminum P/M materials strengthened by dispersion of transition metal compounds and solid solution of Mg , Al -2 mass % Co and Al -5 mass % Co alloys with varied Mg additions of 0, 1 and 5 mass% were prepared by rapid solidification techniques. Rapidly solidified flakes were produced by argon gas atomization and subsequent splat quenching on a water-cooled copper roll. The flakes were consolidated to the P/M (Powder metallurgy process is named as P/M) materials by hot extrusion after vacuum degassing. Cast ingots of these alloys were also hot-extruded under the same conditions to the I/M (Ingot metallurgy process is named as I/M) reference materials. Uniform dispersion of fine intermetallic compounds ( Co 2 Al 9) was observed in all the as-extruded P/M materials. Added Mg was present as the solute in the P/M and I/M materials alloy even after annealing at 773K. The P/M materials containing Mg exhibited higher hardness and strength than those without Mg at room temperature. Tensile strength increased with increasing amount of Mg in the I/M materials at elevated temperatures. However, strength of the P/M materials decreased with addition of Mg at 573K and 673K. According to the steady state creep rate and creep rapture time, the creep resistance of the P/M materials containing Mg was clearly inferior to that of Mg -free alloys. Thus the positive effects of Mg additions on mechanical properties of the P/M materials of Al - Co - Mg alloys disappeared at high temperature.
DYNAMIC MECHANICAL PROPERTIES OF NANOCOMPOSITES WITH POLY (VINYL BUTYRAL) MATRIX
Authors: TORKI A. M. , ŽIVKOVIĆ I. , RADMILOVIĆ V. R. , STOJANOVIĆ D. B. , RADOJEVIĆ V. J. , USKOKOVIĆ P. S. , ALEKSIĆ R. R.
Published: March 2010

This work reports the preparation of SiO 2 and TiO 2/poly (vinyl butyral) nanocomposites with enhanced dynamic mechanical properties. Silica and titania nanoparticles were introduced in the matrix as the neat powder and as colloidal sol using the melt mixing process. Composites reinforced with colloidal sol silica and titania showed higher mechanical properties than the ones reinforced with as-received particles. When sol TiO 2 particles are used, the highest increase of storage modulus of about 54% is obtained for 5 wt% loading, while for sol SiO 2, the storage modulus increases with the addition of nanosilica with the largest increase of about 99% for 7 wt% loading. In addition, nanocomposites were introduced within Kevlar/PVB composites. The addition of 5 wt% silica and titania colloidal sol lead to the remarkable increase of the storage modulus for about 98 and 65%, respectively. Largest contribution of nanoreinforcements in lowering the glass transition temperature is observed for 7 wt% loading of TiO 2 and SiO 2 colloidal sol.
SPIN CURRENT INDUCED ELECTRIC FIELD IN A RASHBA QUANTUM WIRE
Authors: FU XI , ZHOU GUANGHUI
Published: March 2010

We investigate theoretically the spin current and spin current induced electric field in a weak Rashba spin-orbit coupling quantum wire (QW) using a definition for spin current by means of scattering matrix. It is found that there exists two non-zero linear spin current density elements which have oscillation peaks at the center of QW and their strengths can be changed by the number of propagation modes and Rashba constant, respectively. Moreover, the spin current induced electric field has also been calculated and its strength is measurable with present technology with which can be used to detect spin current.
STOCHASTIC AUTOMATA NETWORKS FOR MODELLING SCHEDULING SCHEME IN WiMAX NETWORKS
Authors: MOKDAD LYNDA , BEN-OTHMAN JALEL
Published: March 2010

WiMAX (Worldwide Interpretability for Microwave Access) is one of the leader standards of broadband Wireless Access (BWA). This standard becomes a competitor of 4G or LTE (Long Terme Evolution) with the introduction of different class of service flow (UGS, rtPS, nrtPS, BE). Each service class has its own QoS requirements. Even if the standard specify the transmission policy of each service class, it recommends the implementation of an admission control (AC) without any specification. This task is let to the operator.

In this paper, we propose an implementation of an AC algorithm mechanism for IEEE 802.16. The performance evaluation of these networks by analytical models is not easy due to the state space explosion, thus we use the Stochastic Automata Networks (SAN) formalism to model our proposed AC mechanism. With the SAN we calculate the rewards of the proposed AC and we show that the proposed solution is efficient.
EXCLUSIVE SEQUENCES OF DIFFERENT GENOMES
Authors: MITROFANOV SERGEY I. , PANCHIN ALEXANDER Y. , SPIRIN SERGEI A. , ALEXEEVSKI ANDREI V. , PANCHIN YURI V.
Published: March 2010

We studied the distribution of 1–7 bp words in a dataset that includes 139 complete eukaryotic genomes, 33 masked eukaryotic genomes and coding regions from 35 genomes. We tested different statistical models to determine over- and under-represented words. The method described by Karlin et al. has the strongest predictive power compared to other methods. Using this method we identified over- and under-represented words consistent within a large array of taxonomic groups. Some of those words have not yet been described as exclusive. For example, CGCG is over-represented in CG-deficient organisms. We also describe exceptions for widely known exclusive words, such as CG and TA.
SAROTUP: Scanner and Reporter of Target-Unrelated Peptides
Authors: Huang Jian , Ru Beibei , Li Shiyong , Lin Hao , Guo Feng-Biao
Published: March 2010

As epitope mimics, mimotopes have been widely utilized in the study of epitope prediction and the development of new diagnostics, therapeutics, and vaccines. Screening the random peptide libraries constructed with phage display or any other surface display technologies provides an efficient and convenient approach to acquire mimotopes. However, target-unrelated peptides creep into mimotopes from time to time through binding to contaminants or other components of the screening system. In this study, we present SAROTUP, a free web tool for scanning, reporting and excluding possible target-unrelated peptides from real mimotopes. Preliminary tests show that SAROTUP is efficient and capable of improving the accuracy of mimotope-based epitope mapping. It is also helpful for the development of mimotope-based diagnostics, therapeutics, and vaccines.
Direct Production of a Novel Iron‐Based Nanocomposite from the Laser Pyrolysis of Fe(CO)5/MMA Mixtures: Structural and Sensing Properties
Authors: Alexandrescu R. , Morjan I. , Tomescu A. , Simion C. E. , Scarisoreanu M. , Birjega R. , Fleaca C. , Gavrila L. , Soare I. , Dumitrache F. , Prodan G.
Published: March 2010

Iron/iron oxide‐based nanocomposites were prepared by IR laser sensitized pyrolysis of Fe(CO)5 and methyl methacrylate (MMA) mixtures. The morphology of nanopowder analyzed by TEM indicated that mainly core‐shell structures were obtained. X‐ray diffraction techniques evidence the cores as formed mainly by iron/iron oxide crystalline phases. A partially degraded (carbonized) polymeric matrix is suggested for the coverage of the metallic particles. The nanocomposite structure at the variation of the laser density and of the MMA flow was studied. The new materials prepared as thick films were tested for their potential for acting as gas sensors. The temporal variation of the electrical resistance in presence of NO2, CO, and CO2, in dry and humid air was recorded. Preliminary results show that the samples obtained at higher laser power density exhibit rather high sensitivity towards NO2 detection and NO2 selectivity relatively to CO and CO2. An optimum working temperature of 200°C was found.
Amphiphilic Poly(3-hydroxy alkanoate)s: Potential Candidates for Medical Applications
Authors: Hazer Baki
Published: March 2010

Poly(3-hydroxy alkanoate)s, PHAs, have been very attractive as biomaterials due to their biodegradability and biocompatibility. These hydrophobic natural polyesters, PHAs, need to have hydrophilic character particularly for drug delivery systems. In this manner, poly(ethylene glycol) (PEG) and hydrophilic functional groups such as amine, hydroxyl, carboxyl, and sulfonic acid have been introduced into the PHAs in order to obtain amphiphilic polymers. This review involves in the synthesis and characterization of the amphiphilic PHAs.
Dynamical Aspects of Macroscopic and Quantum Transitions due to Coherence Function and Time Series Events
Authors: Bakhoum Ezzat G. , Toma Cristian
Published: March 2010

This study presents the application of dynamical equations able to generate alternating
deformations with increasing amplitude and delayed pulses in a certain material medium. It is considered that an external force acts at certain time interval (similar to a time series) upon the material medium in the same area. Using a specific differential equation (considering
nonzero initial values and using a function similar to the coherence function between the external force and the deformations inside the material), it results that modulated amplitude oscillations appear inside the material. If the order of the differential dynamical equation is higher, supplementary aspects as different delayed pulses and multiscale behaviour can be noticed. These features are similar to non‐Markov aspects of quantum transitions, and for this reason the mathematical model is suitable for describing both quantum phenomena
and macroscopic aspects generated by sequence of pulses. An example of a quantum system, namely, the Hydrogen atom, is discussed.
Synthesis ofMnO2Microfiber with Secondary Nanostructure by Cotton Template
Authors: Wang Huan-qin , Zheng Ming-bo , Chen Jin-hua , Ji Guang-bin , Cao Jie-ming
Published: March 2010

HierarchicalMnO2microfibers were prepared by using cotton as the template andKMnO4as the precursor via an ultrasonic assistance route. The results of scanning electron microscope characterization showed that the concentration ofKMnO4had a significant effect on the morphology ofMnO2microfiber. At low concentration ofKMnO4, the microfiber was composed ofMnO2nanorods with single crystal structure. With increasing the concentration ofKMnO4, the secondary nanostructure ofMnO2microfibers had a transformation from nanorod to nanoparticle. The results ofN2adsorption-desorption analysis indicated thatMnO2microfibers had BET surface area of about 25 m2/g. This synthesis provides a new way to control the secondary nanostructure ofMnO2microfiber by adjusting the concentration of precursor. Furthermore, the mechanism for the replication was proposed and discussed.
Mosaic and Regulation Phenomena during the Early Formation of the Chick Blastoderm
Authors: Callebaut Marc , Van Nueten Emmy , Harrisson Fernand , Hubens Guy
Published: March 2010

After culturing symmetrically hemisectioned unincubated chicken blastoderms, asymmetric hemiembryos developed (indicating mosaic development). In the present study, we observed that after prolonged culture, the further asymmetric development (way with no possible return) becomes profoundly disturbed, more particularly the Rauber's sickle-dependent phenomena: gastrulation and the formation of the coelomo-cardiovascular complex with absence of heart and pericard development. By contrast, the neural plate develops symmetrically. Asymmetrical ablation of Rauber's sickle and the neighboring upper layer results in the development of an apparently normal symmetrical embryo. Indeed, at the unoperated side, a normal half coelomo-cardiovascular system develops with a unilateral or bilateral heart tube and pericard formation (indicating regulation). Both regulation and mosaicism indicate that during normal early development, the interaction between the left and right sides of the caudal area centralis of the blastoderm is indispensable, depending on the spatial relationship between the elementary tissues (upper layer, Rauber's sickle, endophyll).
Recent GRBs Observed with the 1.23 m CAHA Telescope and the Status of Its Upgrade
Authors: Gorosabel Javier , Kubánek Petr , Jelínek Martin , Castro-Tirado Alberto J. , de Ugarte Postigo Antonio , Castillo-Carrión Sebastián , Guziy Sergey , Cunniffe Ronan , Fernández Matilde , Huélamo Nuria , Terrón Víctor , Morales Nicolás , Ortiz José Luis , Mottola Stefano , Carsenty Uri
Published: March 2010

We report on optical observations of Gamma‐Ray Bursts (GRBs) followed
up by our collaboration with the 1.23 m telescope located at the Calar Alto
observatory. The 1.23 m telescope is an old facility, currently undergoing upgrades
to enable fully autonomous response to GRB alerts. We discuss the
current status of the control system upgrade of the 1.23 m telescope. The upgrade
is being done by our group based on the Remote Telescope System,
2nd Version (RTS2), which controls the available instruments and interacts
with the EPICS database of Calar Alto. (Our group is called ARAE (Robotic Astronomy & High‐Energy Astrophysics) and
is based on members of IAA (Instituto de Astrofísica de Andalucía). Currently the
ARAE group is responsible to develop the BOOTES network of robotic telescopes
(Jelínek et al. 2009).) Currently the telescope can run fully
autonomously or under observer supervision using RTS2. The fast reaction response
mode for GRB reaction (typically with response times below 3 minutes
from the GRB onset) still needs some development and testing. The telescope
is usually operated in legacy interactive mode, with periods of supervised autonomous
runs under RTS2. We show the preliminary results of several GRBs
followed up with observer intervention during the testing phase of the 1.23 m
control software upgrade.
Aquaporin Expression in Normal and Pathological Skeletal Muscles: A Brief Review with Focus on AQP4
Authors: Wakayama Yoshihiro
Published: March 2010

Freeze-fracture electron microscopy enabled us to observe the molecular architecture of the biological membranes. We were studying the myofiber plasma membranes of health and disease by using this technique and were interested in the special assembly called orthogonal arrays (OAs). OAs were present in normal myofiber plasma membranes and were especially numerous in fast twitch type 2 myofibers; while OAs were lost from sarcolemmal plasma membranes of severely affected muscles with dystrophinopathy and dysferlinopathy but not with caveolinopathy. In the mid nineties of the last century, the OAs turned out to be a water channel named aquaporin 4 (AQP4). Since this discovery, several groups of investigators have been studying AQP4 expression in diseased muscles. This review summarizes the papers which describe the expression of OAs, AQP4, and other AQPs at the sarcolemma of healthy and diseased muscle and discusses the possible role of AQPs, especially that of AQP4, in normal and pathological skeletal muscles.
Enhanced MALDI-TOF MS Analysis of Phosphopeptides Using an Optimized DHAP/DAHC Matrix
Authors: Hou Junjie , Xie Zhensheng , Xue Peng , Cui Ziyou , Chen Xiulan , Li Jing , Cai Tanxi , Wu Peng , Yang Fuquan
Published: March 2010

Selecting an appropriate matrix solution is one of the most effective means of increasing the ionization efficiency of phosphopeptides in matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). In this study, we systematically assessed matrix combinations of 2, 6-dihydroxyacetophenone (DHAP) and diammonium hydrogen citrate (DAHC), and demonstrated that the low ratio DHAP/DAHC matrix was more effective in enhancing the ionization of phosphopeptides. Low femtomole level of phosphopeptides from the tryptic digests ofα-casein andβ-casein was readily detected by MALDI-TOF-MS in both positive and negative ion mode without desalination or phosphopeptide enrichment. Compared with the DHB/PA matrix, the optimized DHAP/DAHC matrix yielded superior sample homogeneity and higher phosphopeptide measurement sensitivity, particularly when multiple phosphorylated peptides were assessed. Finally, the DHAP/DAHC matrix was applied to identify phosphorylation sites fromα-casein andβ-casein and to characterize two phosphorylation sites from the human histone H1 treated with Cyclin-Dependent Kinase-1 (CDK1) by MALDI-TOF/TOF MS.
The Effect of an Aqueous Extract ofTeucrium poliumon Glutathione Homeostasis In Vitro: A Possible Mechanism of Its Hepatoprotectant Action
Authors: Shtukmaster Stella , Ljubuncic Predrag , Bomzon Arieh
Published: March 2010

Background.Teucrium poliumis used in Arab traditional medicine to treat liver diseases. Glutathione is an important intracellular antioxidant, and intrahepatic glutathione levels are depleted in liver diseases.Hypothesis and Aim. This investigation tested the hypothesis that aqueous extracts ofT. poliummaintains intracellular glutathione levels by augmenting glutathione peroxidase and glutathione reductase activity in cultured hepatocytes.Methods. The effects of increasing concentrations (0.01–1 mg/mL) of aqueous extract ofT. poliumwere assessed in cultured HepG2 cells following 24 hours incubation on (1) cellular integrity using (a) the Trypan blue exclusion assay, (b) the [di-methylthiazol-2yl]-2,5-diphenyl-tetrazoliumbromide (MTT) assay, and (c) the lactate dehydrogenase (LDH) assay; (2) glutathione redox state; and (3) glutathione peroxidase and glutathione reductase activities using a repeated measures experimental design.Results. At concentrations of 0.375 mg/mL and 0.5 mg/mL, the extract increased the intracellular levels of total and reduced glutathione and had no effect on the intracellular amounts of oxidized glutathione. The extract had no effect on glutathione peroxidase and glutathione reductase activities.Conclusion. These data indicate that the mechanism of the hepatoprotective action of aqueous extracts ofT. poliummay be, in part, due to augmenting intracellular glutathione levels.
Noise-Cancelling CMOS Active Inductor and Its Application in RF Band-Pass Filter Design
Authors: Vema Krishnamurthy Santosh , El-Sankary Kamal , El-Masry Ezz
Published: March 2010

A CMOS active inductor with thermal noise cancelling is proposed. The noise of the transistor in the feed-forward stage of the proposed architecture is cancelled by using a feedback stage with a degeneration resistor to reduce the noise contribution to the input. Simulation results using 90 nm CMOS process show that noise reduction by 80% has been achieved. The maximum resonant frequency and the quality factor obtained are 3.8 GHz and 405, respectively. An RF band-pass filter has been designed based on the proposed noise cancelling active inductor. Tuned at 3.46 GHz, the filter features total power consumption of 1.4 mW, low noise figure of 5 dB, and IIP3 of −10.29 dBm.
Integrin-α5 Mediates Epidermal Growth Factor-Induced Retinal Pigment Epithelial Cell Proliferation and Migration
Authors: Chen Zhen , Chen Chang-zheng , Gong Wen-rong , Li Jun-ping , Xing Yi-qiao
Published: March 2010

Proliferation and migration of retinal pigment epithelial (RPE) cells play a crucial role in proliferative vitreoretinopathy (PVR)-related pathology. Cytokines, including EGF, can result in RPE cell activation and cause PVR. In this study, integrin-α5 expression was first studied in PVR membranes by immunofluorescence. Then the effect of EGF on integrin-α5 expression was determined by flow cytometry, Western blot analysis and the reverse-transcription polymerase chain reaction (RT-PCR) in the ARPE-19 cell line. Proliferation and migration of ARPE-19 cells were measured by the methylthiazolyldiphenyl-tetrazolium bromide and Boyden chamber assays. We found that a higher level integrin-α5 was present at the RPE cell surface in PVR compared with normal retina. EGF could dose dependently increase integrin-α5 mRNA and protein levels in vitro. EGF promoted ARPE-19 cell proliferation and migration. Neutralizing integrin-α5 by specific anti-integrin-α5 antibody abolished most of the effects of EGF. The study provided evidence that EGF might influence PVR by promoting integrin-α5 expression and subsequent proliferation and migration of RPE.
Functionally Active Macrophage-Derived Myeloperoxidase in the Skin of Drug-Induced Toxic Epidermal Necrolysis
Authors: Paquet Philippe , De Groote Donat , Piérard Gérald E.
Published: March 2010

Background: Drug-induced toxic epidermal necrolysis (TEN) probably results from a complex and specific immune cell reaction involving lymphocytes and macrophages. Objective: To assess the functional role of macrophages in TEN. Methods: Immunohistochemistry was performed on biopsies from early blisters developed in 9 TEN patients. The amount of extracellular myeloperoxidase (MPO) was measured by ELISA in TEN blister fluid and serum. Controls were blister fluids taken from 9 second-degree burns. In addition, 3-chlorotyrosine (a specific marker of MPO activity) was searched for using liquid mass chromatography both in TEN and burn blister fluids. Results: Immunohistochemistry revealed numerous CD68+ macrophages in 8/9 TEN patients; 5–20% of these cells and rare CD15+ neutrophils exhibited MPO immunoreactivity, while keratinocytes were negative. The amount of MPO was significantly higher in TEN blister fluid than in TEN serum, suggesting macrophage production of MPO in the skin. In addition, MPO was significantly more abundant in TEN blister fluid than in burn blister fluid. 3-Chlorotyrosine was detected in 7/9 TEN blister fluids, but in only 2/9 burn blister fluids. Discussion: MPO produced by macrophages was functionally active in most TEN patients, leading to the production of hypochlorous acid, a potent oxidative compound that alters keratinocytes.
Prevalence of Acne Vulgaris in Patients with Down Syndrome
Authors: Bagatin Edileia , Kamamoto Cristhine Souza Leão , dos Santos Guadanhim Lilia Ramos , Sanudo Adriana , Costa Dias Marilia , Barraviera Isa Mara , Consolim Colombo Fernanda
Published: March 2010

Background/Objective: Acne vulgaris exhibits a worldwide prevalence of up to 95% among adolescents. On the other hand, Down syndrome is an autosomal chromosomal disorder with associated dermatoses and a tendency to obesity. There are no data on its association with acne. Our aim was to detect the prevalence of acne, its forms and associated factors in Down syndrome. Method: A cross-sectional study including 89 subjects aged 10–28 years from Associação de Pais e Amigos dos Excepcionais-São Paulo to verify acne, metabolic and hormonal disorders by interview, clinical and laboratory examinations. Results: We evaluated 49 (55%) males and 40 (45%) females. A weak agreement between self-estimation for acne and examination result was detected. The overall prevalence of acne was 70.8%: 83.7% in males and 55% in females. The prevalence of acne in the age groups 10–17 and 18–28 was 62 and 78.7%, respectively. Facial comedonal acne was mostly detected. The prevalence of obesity was 40%, that of metabolic disorders 7% and that of hyperandrogenism (in females) 15%. Except for gender, no other factor evaluated correlated with acne. Conclusion: A low prevalence of acne in Down syndrome, a predominance in males aged 18–28 and a facial comedonal form were detected. An association with obesity, metabolic disorders or hyperandrogenemia was not assessed.
Subclinical Choroidal Detachment at Sclerotomy Sites after 23-Gauge Vitrectomy: Analysis by Anterior Segment Optical Coherence Tomography
Authors: Guthoff Rainer , Riederle Heidi , Meinhardt Berit , Goebel Winfried
Published: March 2010

Purpose: Transient ocular hypotony commonly occurs after 23-gauge (23G) vitrectomy. To assess possible causes, we visualized the sclerotomy site and pars plana by anterior segment optical coherence tomography (AS-OCT). Procedures: We prospectively analyzed the intraocular pressure (IOP) and findings related to clinical hypotony, assessed by AS-OCT, in 13 consecutive eyes of 13 patients receiving 23G vitrectomy. Five patients receiving a 20G vitrectomy served as controls. Results: The mean IOP after 23G vitrectomy was 11 mm Hg (range: 5–32 mm Hg; 13 eyes) at postoperative day 1. In contrast to controls, AS-OCT showed a scleral gap at the incision site in 22/39 sclerotomies (10/13 eyes), and subclinical choroidal detachment in 9/13 eyes. Conclusions: A scleral gap and choroidal detachment at the incision site are frequent findings following 23G vitrectomy. These subclinical features may account for postoperative hypotony as they are absent in 20G vitrectomy and scleral sutures. Hypotony following 23G vitrectomy is a self-limiting phenomenon and usually does not require therapeutic intervention.
Anatomic Success of Scleral Buckling for Rhegmatogenous Retinal Detachment – A Retrospective Study of 524 Cases
Authors: Haritoglou Christos , Brandlhuber Ulrich , Kampik Anselm , Priglinger Siegfried G.
Published: March 2010

Background/Aim: Our purpose was to investigate the anatomic success of scleral buckling surgery for rhegmatogenous retinal detachment. Material and Methods: A total of 524 consecutive patients were retrospectively analysed. Several parameters including the lens status, number of breaks and extent of retinal detachment, preoperative proliferative vitreoretinopathy and refractive errors were examined. The minimum follow-up was 6 months. The primary success rate was defined as anatomic success being stable over a period of at least 6 months after surgery. The secondary success rate was defined as anatomic success after the second intervention if necessary. Besides an analysis over all patients, the patients were grouped according to the severity of the preoperative situation in simple, medium and severe cases. Results: The overall primary anatomic success rate was 84.7% and the secondary success rate 96.4% after 1 initial scleral buckling surgery and 1 additional surgery in case of persisting retinal detachment, and 19.1% of the patients with an initially attached retina after 1 scleral buckling surgery experienced a redetachment in the postoperative course and were successfully treated in 60/85 cases. In phakic patients (n = 359) the primary success rate was 89.7%, whereas in pseudophakic patients (n = 165) a primary success rate of 73.9% was obtained. The primary success was additionally influenced by the extent of the retinal detachment measured in clock hours (p < 0.001), undetected holes (p = 0.004), small (p = 0.037) and no gas tamponade (p = 0.021). In simple, medium and severe cases, phakic patients always achieved better anatomic results (89.9, 89.1 and 90.2%) compared to pseudophakic ones (82.5, 70.3 and 36.4%). Conclusion: Scleral buckling is a very good surgical option in phakic patients irrespective of the preoperative severity and simple cases in pseudophakic patients. Scleral buckling represents a surgical technique worth being trained and performed in the light of favourable results especially in phakic eyes.
Characterization and Genome Sequencing of a Novel Coliphage Isolated from Engineered Escherichia coli
Authors: Li Shu , Liu Lina , Zhu Junmin , Zou Lingyun , Li Ming , Cong Yanguang , Rao Xiancai , Hu Xiaomei , Zhou Yingbing , Chen Zhijin , Hu Fuquan
Published: March 2010

Objectives: To characterize morphological, physicochemical and genomic features of a novel virulent coliphage which was isolated from an engineered Escherichia coli culture and termed engineered E. coli phage (EEP). Methods and Results: Electron microscopy revealed that EEP has an icosahedral head (62 nm in diameter) and a long, flexible tail (138 nm in length). EEP was able to infect all 10 engineered E. coli strains kept in our laboratory, showing a strong ability to lyse engineered E. coli. Sequencing of the EEP genome revealed a double-stranded DNA (39.8 kb) with 54.72% GC content. Fifty-two open reading frames were predicted to be coding sequences, 18 of which were functionally defined and organized in a modular format, which includes modules for DNA replication, DNA packaging, structural proteins and host cell lysis. This phage could not be inactivated at 90° for 45 min and was resistant to ethanol and alkali treatment. EEP is assigned to the Siphoviridae family based on its morphological, genomic and physicochemical properties. Conclusions: A novel coliphage was isolated from engineered E. coli strains, and its morphological, genomic and physicochemical properties were characterized, which will improve our knowledge of bacteriophage diversity.
Race/Ethnicity, Quality of Care, and Outcomes in Ischemic Stroke
Authors: Schwamm Lee H. , Reeves Mathew J. , Pan Wenqin , Smith Eric E. , Frankel Michael R. , Olson DaiWai , Zhao Xin , Peterson Eric , Fonarow Gregg C.
Published: March 2010

Background—

Prior studies suggest differences in stroke care associated with race/ethnicity. We sought to determine whether such differences existed in a population of black, Hispanic, and white patients hospitalized with stroke among hospitals participating in a quality-improvement program.

Methods and Results—

We analyzed in-hospital mortality and 7 stroke performance measures among 397 257 patients admitted with ischemic stroke to 1181 hospitals participating in the Get With The Guidelines-Stroke program 2003 through 2008. Relative to white patients, black and Hispanic patients were younger and more often had diabetes mellitus and hypertension. After adjustment for both patient- and hospital-level variables, black patients had lower odds relative to white patients of receiving intravenous thrombolysis (odds ratio [OR], 0.84; 95% confidence interval [CI], 0.77 to 0.91), deep vein thrombosis prophylaxis (OR, 0.88; 95% CI, 0.83 to 0.92), smoking cessation (OR, 0.85; 95% CI, 0.79 to 0.91), discharge antithrombotics (OR, 0.88; 95% CI, 0.84 to 0.92), anticoagulants for atrial fibrillation (OR, 0.84; 95% CI, 0.75 to 0.94), and lipid therapy (OR, 0.91; 95% CI, 0.88 to 0.96), and of dying in-hospital (OR, 0.90; 95% CI, 0.85 to 0.95). Hispanic patients received similar care as their white counterparts on all 7 measures and had similar in-hospital mortality. Black (OR, 1.31; 95% CI, 1.28 to 1.35) and Hispanic (OR, 1.16; 95% CI, 1.11 to 1.20) patients had higher odds of exceeding the median length of hospital stay relative to whites. During the study, quality of care improved in all 3 race/ethnicity groups.

Conclusions—

Black patients with stroke received fewer evidence-based care processes than Hispanic or white patients. These differences could lead to increased risk of recurrent stroke. Quality of care improved substantially in the Get With The Guidelines-Stroke Program over time for all 3 racial/ethnic groups.