bluuebunny/crossref_metadata_2025 huggingface dataset:
Susan Howe's Renaissance Period: Metamorphosis and Representation in Pythagorean Silence and Defenestration of Prague
Authors: WILL MONTGOMERY
Published: November 2006

The American poet Susan Howe is perhaps the best-known of the generation of poets that came to attention under the banner of “language poetry.” Her work has been widely anthologized and it has drawn a considerable amount of critical commentary. The “language” label, like most such tags, was unpalatable to most of the poets who came under it. It did after all mask a diverse range of poets. But, even given such reservations, it was clear from the start that Howe's poetry was out of step with certain general tendencies within language poetry. We know from the correspondence that Ron Silliman was criticized by some language poets for including Howe in his influential 1986 anthology In the American Tree. In a 1985 letter to Howe, Silliman expresses his reading of the relation between her work and language poetry:
I do think one of the most important aspects of this writing [i.e. language writing], from the perspective of literary history if nothing else, is that it is anti-romantic, anti-mystical and anti-lyric (tho there are exceptions …) And your writing does seem to me to be at odds with this larger tendency. How you work with this tension in your poetry seems to me one of its most compelling dimensions.
Refolding and Structural Characteristic of TRAIL/Apo2L Inclusion Bodies from Different Specific Growth Rates of Recombinant Escherichia coli
Authors: Kang Hui , Sun Ai‐You , Shen Ya‐Ling , Wei Dong‐Zhi
Published: November 2006

TNF‐related apoptosis‐inducing ligand (TRAIL/Apo2L) was produced mainly as inclusion bodies (IBs) by recombinant Escherichia coli with a temperature‐inducible expression system. The yield of TRAIL type 2 IBs at higher preinduction specific growth rate (μ = 0.15 h‐1) was higher than that of TRAIL type 1 IBs at lower preinduction specific growth rate (μ = 0.05 h‐1). With the same optimized refolding protocols, two types of IBs exhibited different refolding features. Refolded type 1 IBs had higher recovery of more than 80% compared with type 2 IBs (57–63%). By the measurements of fluorescence and CD spectroscopy, type 1 TRAIL IBs dissolved by urea appeared to be a closer secondary structure to the native TRAIL than type 2. Furthermore, with trypsin treatment, the striking decrease in stability of type 1 IBs against protease digestion cannot be attributed to their small size particles observed by scanning electron microscope and probably depend on different protein structure properties between the two IBs. Different properties of inclusion bodies were mainly influenced by different physiological states of the cells just prior to the induction.
Melatonin im Alter und bei Alzheimer-Demenz
Authors: Savaskan
Published: November 2006

Das Epiphysenhormon Melatonin hat neben seiner regulierenden Rolle auf zirkadiane Rhythmen im Organismus und seiner schlafanstossenden Wirkung weitere physiologische Wirkungen wie z.B. vasoaktive und neuromodulatorische Eigenschaften. Die antioxidative Potenz des Melatonins ist die Basis seiner neuroprotektiven Funktion gegen oxidativen Stress, welcher wesentlich zur Pathologie neurodegenerativer Erkrankungen wie der Alzheimer-Demenz beiträgt. Auch wenn die Datenlage aus der Grundlagenforschung vielversprechend ist, fehlen bisher grössere klinische Studien, die die Wirksamkeit belegen. Im folgenden Text wird die Rolle dieser natürlichen Substanz im Alter und im Verlauf der Alzheimer- Demenz diskutiert.
Physical initialization applied in WRF‐Var for assimilation of Doppler radar data
Authors: Yang Yi , Qiu Chongjian , Gong Jiandong
Published: November 2006

WRF‐Var is further developed with Physical Initialization (PI) to assimilate Doppler radar radial velocity and reflectivity observations. In this updated 3D‐Var, specific humidity and vertical velocity are first derived from reflectivity with PI, and then the model fields of specific humidity are replaced by the modified ones, finally, the estimated vertical velocity is added to the cost‐function of the existing WRF‐Var (version 2.0) as a new observation type, and radial velocity observations are assimilated directly by the method afforded by WRF‐Var. It is tested with a rainfall event that occurred in Hubei province near the Yangtze River on 19 June 2002. Results show that the updated 3D‐Var shows better capability to forecast the precipitation than the WRF‐Var does, and the forecast reflectivity field correlates well with the observations for about 4‐h prediction period.
Magnetically self‐consistent ring current simulations during the 19 October 1998 storm
Authors: Chen Margaret W. , Liu Shuxiang , Schulz Michael , Roeder James L. , Lyons Larry R.
Published: November 2006

We investigate effects of magnetic self‐consistency on ring current development by calculating equatorial particle transport in a model that feeds back the ring current on the magnetospheric configuration. The equatorial magnetic intensity is computed by solving a force‐balance equation in the equatorial plane. This force‐balance computation is coupled to a kinetic proton and electron drift‐loss model. The electric field model used includes corotation, quiescent Volland‐Stern convection, and storm‐associated enhancements in the convection. We have modeled the 19 October 1998 storm (min Dst = −112 nT) by using the total cross polar cap potential from AMIE to determine the amplitudes of storm‐associated electric field enhancements. We trace equatorially mirroring protons and electrons within this model. We have found that self‐consistent feedback between plasma pressure and the magnetic field tends to mitigate the energization associated with inward particle transport as the ring current forms. At a given first adiabatic invariant and radial distance, the self‐consistent magnetic field reduces the E × B drift rate as it significantly enhances the azimuthal gradient‐B drift rate. Especially later in the main phase, there can be places where the plasma pressure and magnetic perturbation are locally enhanced by making the simulation magnetically self‐consistent because of enhanced drift rates in regions of reduced magnetic intensity. The southward magnetic perturbation at the center of the Earth, which represents the ring current contribution to the Dst index, is reduced by about 25% by making the simulation magnetically self‐consistent. This suggests that simulations that do not take account of the feedback of the ring current overestimate the actual ring current intensity.
Electrodynamics of a split‐transpolar aurora
Authors: Eriksson S. , Provan G. , Rich F. J. , Lester M. , Milan S. E. , Massetti S. , Gosling J. T. , Dunlop M. W. , Rème H.
Published: November 2006

We report new results on the relation between drift velocity shear, average inverted V energy, and the separation of bifurcated high‐latitude Sun‐aligned polar arcs within a global transpolar auroral arc system. The two parallel arcs appeared at the location of converging −v × B electric field of two sunward flow channels that were separated by an intermediate region of much weaker antisunward flow. The flow shear consisted of differences mainly in the magnitude of the sunward drift velocity. The cross‐track disturbance magnetic field was in phase with the drift velocity fluctuations in such a way that two upward field‐aligned currents coincided with the peak average energy of the electron precipitation that generated the two polar arcs while a downward field‐aligned current was observed in the intermediate region. The observed transverse arc separation is consistent with a reported linear dependence between the average energy of the precipitating electrons of the two arcs and the arc separation. We propose that this relation mainly follows from a local Pedersen current closure requirement. The greater the upward field‐aligned current density of the two arcs, the wider the transverse region of the intermediate downward field‐aligned current needs to be in order to supply a sufficient amount of current carriers to the bifurcated arc current circuit and thus to balance the Pedersen current.
Pan‐Arctic enhancements of light absorbing aerosol concentrations due to North American boreal forest fires during summer 2004
Authors: Stohl A. , Andrews E. , Burkhart J. F. , Forster C. , Herber A. , Hoch S. W. , Kowal D. , Lunder C. , Mefford T. , Ogren J. A. , Sharma S. , Spichtinger N. , Stebel K. , Stone R. , Ström J. , Tørseth K. , Wehrli C. , Yttri K. E.
Published: November 2006

During summer of 2004, about 2.7 million hectare of boreal forest burned in Alaska, the largest annual area burned on record, and another 3.1 million hectare burned in Canada. This study explores the impact of emissions from these fires on light absorbing aerosol concentration levels, aerosol optical depths (AOD), and albedo at the Arctic stations Barrow (Alaska), Alert (Canada), Summit (Greenland), and Zeppelin/Ny Ålesund on Spitsbergen (Norway). The Lagrangian particle dispersion model FLEXPART was run backward from these sites to identify periods that were influenced by forest fire pollution plumes. It is shown that the fires led to enhanced values of particle light absorption coefficients (σap) at all of these sites. Barrow, about 1000 km away from the fires, was affected by several fire pollution plumes, one leading to spectacularly high 3‐hour mean σap values of up to 32 Mm−1, more than the highest values measured in Arctic Haze. AOD measurements for a wavelength of 500 nm saturated but were estimated at above 4–5 units, unprecedented in the station records. Fire plumes were transported through the atmospheric column over Summit continuously for 2 months, during which all measured AOD values were enhanced, with maxima up to 0.4–0.5 units. Equivalent black carbon concentrations at the surface at Summit were up to 600 ng m−3 during two major episodes, and Alert saw at least one event with enhanced σap values. FLEXPART results show that Zeppelin was located in a relatively unaffected part of the Arctic. Nevertheless, there was a 4‐day period with daily mean σap > 0.3 Mm−1, the strongest episode of the summer half year, and enhanced AOD values. Elevated concentrations of the highly source‐specific compound levoglucosan positively confirmed that biomass burning was the source of the aerosols at Zeppelin. In summary, this paper shows that boreal forest fires can lead to elevated concentrations of light absorbing aerosols throughout the entire Arctic. Enhanced AOD values suggest a substantial impact of these plumes on radiation transmission in the Arctic atmosphere. During the passage of the largest fire plume, a pronounced drop of the albedo of the snow was observed at Summit. We suggest that this is due to the deposition of light absorbing particles on the snow, with further potentially important consequences for the Arctic radiation budget.
Evaluation of the Second Global Soil Wetness Project soil moisture simulations: 2. Sensitivity to external meteorological forcing
Authors: Guo Zhichang , Dirmeyer Paul A. , Hu Zeng‐Zhen , Gao Xiang , Zhao Mei
Published: November 2006

The quality of meteorological forcing data has a strong impact on the simulation of the land surface component of the hydrological cycle. In this paper, the sensitivity of soil moisture simulations to combinations of different external meteorological forcing and vegetation parameters supplied by the International Satellite Land‐Surface Climatology Project (ISLSCP) Initiative II (II2) as part of the Second Global Soil Wetness Project (GSWP‐2) is evaluated by using the SSiB land surface model. The simulated plant‐available soil moisture in the top 1 m of soil is compared against in situ observations over grasslands and agricultural regions in the former Soviet Union, United States (Illinois), China, and Mongolia from the Global Soil Moisture Data Bank. It is found that the skill of the simulations is very sensitive to the source of meteorological forcing and that hybridization of reanalysis products with observational data substantially improves the soil moisture simulations compared to reanalysis data alone. Sensitivity is highest among products of precipitation, radiation, and vegetation class. The range of changes in the skill of soil moisture simulations with the same land surface model in 13 different sensitivity studies is as large as that resulting from 11 different land surface models driven with the same meteorological forcing from the baseline integrations of GSWP‐2. Assuming differences among versions of meteorological forcing fields are indicative of uncertainties in our knowledge of these drivers of the land surface climate, the impact of that uncertainty on land surface hydrology is as large as that from the variations among land surface models.
X-ray diffraction and inelastic neutron scattering study of 1:1 tetramethylpyrazine chloranilic acid complex: temperature, isotope, and pressure effects
Authors: Prager M. , Pietraszko A. , Sobczyk L. , Pawlukojć A. , Grech E. , Seydel T. , Wischnewski A. , Zamponi M.
Published: November 2006

The x-ray diffraction studies of the title complex were carried out at room temperature and 14K for H∕D (in hydrogen bridge) isotopomers. At 82K a phase transition takes place leading to a doubling of unit cells and alternation of the hydrogen bond lengths linking tetramethylpyrazine (TMP) and chloranilic acid molecules. A marked H∕D isotope effect on these lengths was found at room temperature. The elongation is much smaller at 14K. The infrared isotopic ratio for O–H(D)⋯N bands equals to 1.33. The four tunnel splittings of methyl librational ground states of the protonated complex required by the structure are determined at a temperature T=4.2K up to pressures P=4.7kbars by high resolution neutron spectroscopy. The tunnel mode at 20.6μeV at ambient pressure shifts smoothly to 12.2μeV at P=3.4kbars. This is attributed to an increase of the strength of the rotational potential proportional to r−5.6. The three other tunnel peaks show no or weak shifts only. The increasing interaction with diminishing intermolecular distances is assumed to be compensated by a charge transfer between the constituents of δe∕e∼0.02kbar−1. The phase transition observed between 3.4 and 4.7kbars leads to increased symmetry with only two more intense tunneling bands. In the isotopomer with deuterated hydrogen bonds and P=1bar all tunnel intensities become equal in consistency with the low temperature crystal structure. The effect of charge transfer is confirmed by a weakening of rotational potentials for those methyl groups whose tunnel splittings were independent of pressure. Density functional theory calculations for the model TMP∙(HF)2 complex and fully ionized molecule TMP+ point out that the intramolecular rotational potential of methyl groups is weaker in the charged species. They do not allow for the unequivocal conclusions about the role of the intermolecular charge transfer effect on the torsional frequencies.
Particle transport in reversed field pinch helium plasmas
Authors: Lorenzini R. , Auriemma F. , Canton A. , Carraro L.
Published: November 2006

The isotope effect is known to influence the transport in tokamak machines. In this paper is investigated the isotope effect in the reversed field pinch configuration comparing the particle transport in He and H discharges in the reversed field pinch experiment [G. Rostagni, Fusion Eng. Des. 25, 301 (1995)]. The theory of transport in a stochastic magnetic field predicts a weak isotope effect on the particle transport. The analyses show that the experimental results are in agreement with this theory in the plasma core, where the transport is dominated by the magnetic fluctuations. At the edge, where the transport is due to electrostatic fluctuations, the analyses indicate there may be an isotope mass per charge effect at high density that may disappear when n<6×1019m−3.
Influence of interface roughness on two-dimensional electron gas streaming transport in GaN-based heterostructures
Authors: Polyakov V. M. , Schwierz F.
Published: November 2006

Streaming transport of the two-dimensional (2D) electron gas in a model GaN-based heterostructure is investigated using the ensemble Monte Carlo simulation method. It is demonstrated that interface roughness (IFR) scattering, being, in contrast to three-dimensional (3D) transport, an additional relevant scattering mechanism, plays a crucial role in fulfilling the streaming conditions for 2D transport. For a calculation of the IFR scattering rates we use the widely adopted Gaussian and exponential autocovariance functions to quantitatively describe the interface roughness. Even neglecting the interface roughness the streaming conditions are fulfilled only at low temperatures, similar to the 3D case. Taking into account IFR scattering, the nearly quasiballistic motion of 2D electrons in the passive region (below the optical phonon energy ℏωLO), being one of the necessary conditions for the streaming transport, can be realized only for sufficiently smooth interfaces.
Examining the oxygen isotope and magnetic field effect on phase separation in Sm0.5Sr0.5MnO3
Authors: Styka A. N. , Ren Y. , Gorbenko O. Yu. , Babushkina N. A. , Brown D. E.
Published: November 2006

Magnetic field (MF) dependence of the phase separation (PS) in the manganites Sm0.5Sr0.5MnO3 with O16 and O18 was studied using high-resolution high-energy x-ray powder diffraction in the temperature range from 4.2 to 240 K and with the MF up to 6 T. Although the two compounds have an identical structure [a paramagnetic (PM) phase with the Pbnm symmetry] at room temperature, they show a significant difference in the PS region below Tps∼110 K, where the O16 sample has a structural inhomogeneity in the form of two coexisting ferromagnetic (FM) and antiferromagnetic (AF) phases, while the O18-sample phase separates into mixed AF and PM phases. The O16→O18 isotope substitution appears to prevent the formation of the FM phase at low temperature. The application of a magnetic field significantly enhances the FM phase by converting other phases, leading to a homogeneous structure. The effects on the microscopic structure of the oxygen isotope substitution and external magnetic field play the key role in the physics behind the colossal magnetoresistance effect.
Hysteresis of hexagonal arrays of magnetic nanodots
Authors: Xue Desheng , Yan Zhongjie
Published: November 2006

The magnetization in an infinite two-dimensional hexagonal array of small magnetic single-domain nanoparticles is studied by theoretical calculations. Various hysteresis loops and analytical expressions of coercivity and saturation field of the system with different particle sizes and array densities are obtained under the assumption of magnetization reversal mechanisms based on the competition between the dipolar interaction energy and the shape anisotropy energy with an external magnetic field perpendicular to the array plane. The hysteresis loop varies from a rectangle to a nonhysteresis straight line through a set of complicated loops composed of two types, which is in accordance with the magnetization reversal process varying from an independent coherent rotation to an “antisymmetric-ferromagnetic chain” mechanism. Our results can give a reasonable reference to the application of perpendicular magnetic recording media.
Electric field tweezers for characterization of liquid surface
Authors: Sakai K. , Yamamoto Y.
Published: November 2006

The authors have developed a novel technique to measure the surface properties of soft condensed matters in a noncontact manner. In this method, the Maxwell stress applied by a needle electrode deforms the surface. The magnitude of the displacement is determined by the surface tension as the restoring force, while its dynamic response is determined by the sample viscosity. The surface tension was measured for the aqueous solutions of the surfactant sodium dodecyl sulfate at various concentrations and the result shows good agreement with the conventional method. Further, the viscosity measurement was also carried out in the range of 0.1–103Pas.
Three-channel KrF laser with distributed magnetic-switch-based charging circuit
Authors: Szatmári S. , Bohus J. , Zhixing G. , Tang X. , Wang N.
Published: November 2006

A novel magnetic-switch-controlled L−C inversion circuit is proposed for discharge pumped excimer lasers of three separate channels. The charging circuit is controlled by one thyratron and one common “distributed” magnetic switch. Stable synchronization of the channels and the capability for amplification or generation of three separate pulses of constant delay are unique features of this scheme.
From the adhesion of atomic clusters to the fabrication of nanodevices
Authors: Reichel R. , Partridge J. G. , Natali F. , Matthewson T. , Brown S. A. , Lassesson A. , Mackenzie D. M. A. , Ayesh A. I. , Tee K. C. , Awasthi A. , Hendy S. C.
Published: November 2006

An experimental study of Bi, Sb, and Cu clusters incident at velocities ≳50m∕s on SiO2, Si3N4, polymethylmethacrylate, and photoresist surfaces shows that the clusters adhere much more strongly to SiO2 and Si3N4 than to the polymer materials. The differences in adhesion properties allow assembly of a range of nanowire-based electronic devices from cluster building blocks using lithographically patterned polymer layers. Clusters adhere to the substrate but not to the surface of the polymer template, eliminating parasitic conduction. Molecular dynamics simulations show that differing cluster-surface interactions affect adhesion most strongly when high incident velocities cause significant plastic deformation of the clusters.
High intrinsic permittivity in Na1∕2Bi1∕2Cu3Ti4O12
Authors: Ferrarelli Matthew C. , Adams Timothy B. , Feteira Antonio , Sinclair Derek C. , West Anthony R.
Published: November 2006

The electrical properties of Na1∕2Bi1∕2Cu3Ti4O12 (NBCTO) ceramics between ∼8 and 400K are electrically inhomogeneous, consisting of semiconducting grains and insulating grain boundaries, similar to isostructural CaCu3Ti4O12 (CCTO); however, the intrinsic permittivity of NBCTO of ∼250 at 10K is much higher compared to ∼110 for CCTO. Possible explanations for this high intrinsic permittivity are discussed.
Resonant frequency response of plasma wave detectors
Authors: Kang Sungmu , Burke Peter J. , Pfeiffer L. N. , West K. W.
Published: November 2006

Resonant behavior in the frequency dependent responsivity of a high electron mobility transistor based plasma wave detector from 0.1to6GHz is clearly demonstrated at T=0.3to4K. By independently determining the frequency dependent power coupling, the authors are able to measure the absolute responsivity of the device. Clear peaks in the responsivity are observed at 2.0 and 4.4GHz. At elevated temperatures up to 20K, the resonant behavior vanishes due to increased phonon scattering. Taken collectively these experiments provide strong evidence that plasma wave rectification is the dominant mechanism of device response.
Carbon chains and the (5,5) single-walled nanotube: Structure and energetics versus length
Authors: Rodriguez Kenneth R. , Williams Shaun M. , Young Matt A. , Teeters-Kennedy Shannon , Heer Joseph M. , Coe James V.
Published: November 2006

Reliable thermochemistry is computed for infinite stretches of pure-carbon materials including acetylenic and cumulenic carbon chains, graphene sheet, and single-walled carbon nanotubes (SWCNTs) by connection to the properties of finite size molecules that grow into the infinitely long systems. Using ab initio G3 theory, the infinite cumulenic chain (:CCCC:) is found to be 1.9±0.4kcal∕mol per carbon less stable in free energy at room temperature than the acetylenic chain (C∙C–CC∙) which is 24.0kcal∕mol less stable than graphite. The difference between carbon-carbon triple, double, and single bond lengths (1.257, 1.279, and 1.333Å, respectively) in infinite chains is evident but much less than with small hydrocarbon molecules. These results are used to evaluate the efficacy of similar calculations with the less rigorous PM3 semiempirical method on the (5,5) SWCNT, which is too large to be studied with high-level ab initio methods. The equilibrium electronic energy change for C(g)→C[infinite (5,5) SWCNT] is −166.7kcal∕mol, while the corresponding free energy change at room temperature is −153.3kcal∕mol (6.7kcal∕mol less stable than graphite). A threefold alternation (6.866, 6.866, and 6.823Å) in the ring diameter of the equilibrium structure of infinitely long (5,5) SWCNT is apparent, although the stability of this structure over the constant diameter structure is small compared to the zero point energy of the nanotube. In general, different (n,m) SWCNTs have different infinite tube energetics, as well as very different energetic trends that vary significantly with length, diameter, and capping.
Magic alkali-fullerene compound clusters of extreme thermal stability
Authors: Enders A. , Malinowski N. , Ievlev D. , Zurek E. , Autschbach J. , Kern K.
Published: November 2006

The thermal stability of free pure C60-, as well as C60-alkali, and -alkaline-earth metal compound clusters is investigated. We find that small (C60)m-clusters (m⩽6) decay at comparatively low temperatures below 400K, as a consequence of weak intermolecular van der Waals interaction. Adding barium or potassium to the clusters dramatically increases the decay temperatures for “magic” configurations of (C60)mBa2m−1 and (C60)mK2m, which reach values as high as 1780K. Contrary to common belief, the superstable compound clusters are not characterized by filled geometrical or electronic shells. Density functional calculations show that the delicate interplay of ionic (K, Ba) and covalent (Ba) interaction between C60 and the metal atoms, on the one hand, and entropic contributions to the Gibbs free energy, on the other hand, determine the unusual stability.
Organomercury compounds. XIV. The preparations of bispolychlorophenylmercury compounds by mercuration reactions
Authors: Bertino RJ , Deacon GB , Taylor FB
Published: November 2006

The bispolychlorophenylmercurials
R2Hg (R = C6Cl5 2,3,4,5-Cl4H,
2,3,4,6- Cl4C6H
2,3,5,6-C14C6H, 2,3,4-Cl3C6H2,
2,4,6-Cl2C6H2, and 2,5-Cl2C6H3)
have been prepared by direct mercuration of pentachlorobenzene,
1,2,3,4-tetrachlorobenzene, 1,2,3,5-tetrachlorobenzene,
1,2,4,5-tetraohlorobenzene, 1,2,3-trichlorobenzene, 1,3,5-trichlorobenzene, and
1,4-dichlorobenzene respectively, with mercuric trifluoroacetate at elevated
temperatures. Similar syntheses of bispentachlorophenylmercury
from mercuric difluoroacetate and fluoroacetate have
also been carried out. From merouration of pentaohlorobenzene with mercuric trifluoroaoetate
and difluoroacetate under milder conditions, pentachlorophenylmercuric trifluoroacetate and difluoroacetate have been obtained. The former undergoes
thermal decomposition into bispenta

chlorophenylmercury and mercuric trifluoroacetate.
Effects of a preovulatory administered depot gonadotrophin-releasing hormone agonist on reproductive hormone levels and pregnancy outcome in gilts
Authors: Schneider F. , Brüssow K.-P.
Published: November 2006

The present study aimed to explore the influence of a preovulatory administered depot gonadotrophin-releasing hormone (GnRH) agonist (GnRHa; Decapeptyl®Depot) on the endocrine parameters and pregnancy outcome of gilts (n = 6). A GnRHa-supported preovulatory luteinising hormone (LH) surge was detected in all treated gilts. LH pulses were abolished completely by depot GnRHa on Day 7 and partly on Day 21 of pregnancy. In this treatment group (n = 6) four gilts were pregnant at slaughter on Day 28. In the control group receiving Gonavet®, a non-formulated GnRHa (n = 6), all pigs showed LH pulses and were pregnant at slaughter on Day 28 of gestation. Mean progesterone concentrations were elevated in controls during the early luteal phase and were similar for both groups during the implantation period. Mean concentration of unoccupied progesterone receptor was significantly higher in uterine myometrium than in endometrium, but without treatment effects. Peripheral estrone sulfate concentrations showed a similar increase in all pregnant gilts on Days 17 and 18, and remained elevated. In summary, treatment with a depot GnRHa for synchronisation of ovulation alters pulsatile LH secretion during early pregnancy in pigs. In general, this alteration seems not to exert an injurious influence on luteal function and, therefore, on embryo and early fetal development.
The Primate Embryo Gene Expression Resource in embryology and stem cell biology
Authors: Latham Keith E.
Published: November 2006

The analysis of temporal patterns of gene expression in embryos is an essential component of any research program seeking to understand molecular mechanisms that control development. Little is known of early regulatory mechanisms that operate in primate oocytes and preimplantation-stage embryos. Such studies have been hindered by the cost of obtaining, and limited availability of, non-human primate oocytes and embryos, and by ethical and legal constraints on studies of human embryos. Over the past 4 years we have established the Primate Embryo Gene Expression Resource (PREGER) to circumvent these limitations. A set of over 200 samples of rhesus monkey oocytes and embryos has been converted to cDNA libraries, which are, in turn, used for a variety of molecular analyses. Both the libraries and cDNA dot blots can be distributed free of charge to anyone wishing to study gene expression at these stages. This includes providing an inexpensive and rapid method for confirming and extending results of gene discovery approaches such as microarray analysis. PREGER includes an on-line resource with a database and other useful tools for embryologists. The resource is being expanded to incorporate samples from other species and from embryonic stem cells.
Quantifying the relation between adhesion ligand–receptor bond formation and cell phenotype
Authors: Kong Hyun Joon , Boontheekul Tanyarut , Mooney David J.
Published: November 2006

One of the fundamental interactions in cell biology is the binding of cell receptors to adhesion ligands, and many aspects of cell behavior are believed to be regulated by the number of these bonds that form. Unfortunately, a lack of methods to quantify bond formation, especially for cells in 3D cultures or tissues, has precluded direct probing of this assumption. We now demonstrate that a FRET technique can be used to quantify the number of bonds formed between cellular receptors and synthetic adhesion oligopeptides coupled to an artificial extracellular matrix. Similar quantitative relations were found between bond number and the proliferation and differentiation of MC3T3-E1 preosteoblasts and C2C12 myoblasts, although the relation was distinct for each cell type. This approach to understanding 3D cell–extracellular matrix interactions will allow one to both predict cell behavior and to use bond number as a fundamental design criteria for synthetic extracellular matrices.
A
Legionella pneumophila
-translocated substrate that is required for growth within macrophages and protection from host cell death
Authors: Laguna Rita K. , Creasey Elizabeth A. , Li Zhiru , Valtz Nicole , Isberg Ralph R.
Published: November 2006

Legionella pneumophila
requires the Dot/Icm protein translocation system to replicate within host cells as a critical component of Legionnaire's pneumonia. None of the known individual substrates of the translocator have been shown to be essential for intracellular replication. We demonstrate here that mutants lacking the Dot/Icm substrate SdhA were severely impaired for intracellular growth within mouse bone marrow macrophages, with the defect absolute in triple mutants lacking
sdhA
and its two paralogs. The defect caused by the absence of the
sdhA
family was less severe during growth within
Dictyostelium discoideum
amoebae, indicating that the requirement for SdhA shows cell-type specificity. Macrophages harboring the
L. pneumophila sdhA
mutant showed increased nuclear degradation, mitochondrial disruption, membrane permeability, and caspase activation, indicating a role for SdhA in preventing host cell death. Defective intracellular growth of the
sdhA
−
mutant could be partially suppressed by the action of caspase inhibitors, but caspase-independent cell death pathways eventually aborted replication of the mutant.
The Effect of Cyclosporin A on Alveolar Bone in Rats Subjected to Experimental Periodontal Disease
Authors: Cetinkaya Burcu Ozkan , Acikcoz Gokhan , Keles Gonca Cayir , Ayas Bulent , Korkmaz Adnan
Published: November 2006

Cyclosporine A (CsA), broadly used in organ transplantation, may contribute to pathogenesis of osteoporosis. The aim of this study was to investigate the effects of CsA on alveolar bone in rats subjected or not to experimental periodontal disease using biochemical, radiographic, and histometric analysis. Forty Wistar rats were divided into 4 equal groups: Group I (Control), Group II (CsA was injected subcutaneously in a daily dose of 10 mg/kg), Group III (Ligature was placed around the mandibular molars), Group IV (Ligature+CsA). After 60 days, rats were decapitated, serum alkaline phosphatase and calcium levels were measured. Radiographic-alveolar bone loss (ABL), histometric-ABL, and percentage of new alveolar bone formation (NABF%) were determined on mandibular molars. Significant increase in serum alkaline phosphatase levels ( p < 0.001), no significant difference in calcium levels were observed ( p > 0.05) in Group IV compared to Group III. Radiographic and histometric-ABL were significantly less ( p < 0.001), NABF% was significantly greater ( p < 0.05) in Group IV than in Group III. No significant difference in any of the parameters between Group II and Group I was found. It can be concluded that in the presence of periodontal disease, CsA treatment may bring out an imbalance in the alveolar bone homeostasis by decreasing resorption and stimulating formation of alveolar bone in rats.
Changes in European ecosystem productivity and carbon balance driven by regional climate model output
Authors: MORALES PABLO , HICKLER THOMAS , ROWELL DAVID P. , SMITH BENJAMIN , SYKES MARTIN T.
Published: November 2006

Climate change resulting from the enhanced greenhouse effect together with the direct effect of increased atmospheric CO2 concentrations on vegetation growth are expected to produce changes in the cycling of carbon in terrestrial ecosystems. Impacts will vary across Europe, and regional‐scale studies are needed to resolve this variability. In this study, we used the LPJ‐GUESS ecosystem model driven by a suite of regional climate model (RCM) scenarios from the European Union (EU) project PRUDENCE to estimate climate impacts on carbon cycling across Europe. We identified similarities and discrepancies in simulated climate impacts across scenarios, particularly analyzing the uncertainties arising from the range of climate models and emissions scenarios considered. Our results suggest that net primary production (NPP) and heterotrophic respiration (Rh) will generally increase throughout Europe, but with considerable variation between European subregions. The smallest NPP increases, and in some cases decreases, occurred in the Mediterranean, where many ecosystems switched from sinks to sources of carbon by 2100, mainly as a result of deteriorating water balance. Over the period 1991–2100, modeled climate change impacts on the European carbon balance ranged from a sink of 11.6 Gt C to a source of 3.3 Gt C, the average annual sink corresponding with 1.85% of the current EU anthropogenic emissions. Projected changes in carbon balance were more dependent on the choice of the general circulation model (GCM) providing boundary conditions to the RCM than the choice of RCM or the level of anthropogenic greenhouse gases emissions.
Results for 79 patients with neuroblastoma detected through mass screening at 6 months of age in a single institute
Authors: NISHIO NOBUHIRO , MIMAYA JUN‐ICHI , NARA TAEMI , TAKASHIMA YOSHIFUMI , HORIKOSHI YASUO , URUSHIHARA NAOTO , HASEGAWA SHIRO , AOKI KATSUHIKO , HAMASAKI MINORU
Published: November 2006

Background: In Japan, mass screening for neuroblastoma has been performed at 6 months of age to improve the prognosis of this condition for more than 20 years. In recent years, most neuroblastomas detected by mass screening were considered to have favorable biological features and sometimes tend to regress spontaneously.

Methods: The authors established non‐treated observation criteria in 1997 and criteria for observation of residual tumor after first‐line chemotherapy in 1999, and have made an effort to reduce the intensity of medical treatment for neuroblastoma. The authors examined outcomes of 79 patients who were found in the Shizuoka neuroblastoma mass screening at 6 months of age and who received medical treatment or underwent observation in Shizuoka Children’s Hospital, Shizuoka, Japan, between December 1981 and December 2004.

Results: A total of 77 patients survived but the remaining two patients died from complications of medical treatment. None of the patients died due to progression of neuroblastoma. In the cases, non‐treated observation was performed in 17. Of those, 12 patients are now under non‐treated observation. Of their tumors, two have disappeared, nine have become smaller and another one has not change in size. Observation of residual tumor after first‐line chemotherapy was performed in 15 cases, and three disappeared and the other 12 cases became smaller. Medical treatment‐related complications were observed in 20 of 67 patients who received medical treatment, and 18 of the 20 patients were seen before establishing non‐treated observation criteria.

Conclusion: Non‐treated observation and observation of residual tumor after first‐line chemotherapy were useful to reduce medical treatment‐related complications.
Failure of medical therapy despite normal intraocular pressure
Authors: Walland Mark J , Carassa Roberto G , Goldberg Ivan , Grehn Franz , Heuer Dale K , Khaw Peng T , Thomas Ravi , Parikh Rajul
Published: November 2006

Abstract

The disease glaucoma is now defined by characteristic optic disc and visual field change, without specific reference to the intraocular pressure (IOP). Success of treatment is no longer judged by the mere attainment of IOP less than 21 mmHg. Controversy remains, however, in deciding appropriate management where optic disc and/or visual field damage continues to progress despite a ‘normal’ IOP having been achieved with medical treatment. A panel of international glaucoma experts has provided management recommendations in four clinical scenarios – open‐angle glaucoma, open‐angle glaucoma in a myopic contact lens wearer, uveitic glaucoma and open‐angle glaucoma in combination with visually significant cataract – where optic nerve and visual field progression has continued despite an IOP less than 21 mmHg on full medical treatment. Surgical intervention with mitomycin trabeculectomy is the most favoured further therapy.
The importance of seasonal variability and tactical responses to risk on estimating the economic benefits of integrated weed management
Authors: Jones Randall , Cacho Oscar , Sinden Jack
Published: November 2006

Seasonal variability is an important source of risk faced by farmers and, regardless of an individual's attitude to risk, there are options to tactically adjust production strategies as the outcomes of risk become known. The objective of this article is to measure the economic benefits of alternative approaches to managing weeds, one of the most serious production problems in Australian cropping systems. A bioeconomic model that combines weed biology, crop growth and economics is developed to value the effects of seasonal variability and the role of tactical responses and sequential decision making in determining an optimal integrated weed management strategy. This shows that there are substantial differences in the measured long‐term benefits from deterministic and stochastic simulations. It is concluded that, for research evaluation of technologies that involve complex biological and dynamic systems, ignoring the impacts of seasonal variability, responses to risk and sequential decision making can lead to an incorrect estimate of the economic benefits of a technology. In this case study of optimal weed management strategies in Australia, the size of the error is high.
Modeling farmers' decisions on child labor and schooling in the cocoa sector: a multinomial logit analysis in Côte d'Ivoire
Authors: Nkamleu Guy B. , Kielland Anne
Published: November 2006

Since 2000, children working in the cocoa sector of Côte d'Ivoire have found themselves in the media spotlight. This situation has assumed particular importance because approximately 40% of the world's cocoa production occurs in Côte d'Ivoire. Concerned parties have since taken great interest in this thorny issue. There is a need to better understand the reality of child labor utilization in this sector. This article investigates child labor issues in the cocoa sector of Côte d'Ivoire in conjunction with schooling status of children. The study is based on a survey done in 2002, over a representative sample of more than 11,000 members of cocoa households. The multinomial logit model is used to capture choice probabilities across work and/or school options. The results reveal that child labor in cocoa farms and nonenrollment in schools are significant. Moreover, many children are involved in potentially dangerous and/or harmful tasks. Data also highlight gender and age dimensions in the participation of children in tasks and the way labor is allocated. Econometric results generally indicate that the gender and age of children, whether or not the child is the biological child of the household head, parents' education, the origin of the farmer, household welfare, household size, the household dependency ratio, the size of other perennial crop farms, the number of sharecroppers working with the household head, and communities' characteristics are all pertinent in explaining the child work/schooling outcome in the cocoa sector of Côte d'Ivoire.
APPLICATION OF RESPONSE SURFACE METHODOLOGY FOR THE OSMOTIC DEHYDRATION OF CARROTS
Authors: SINGH BAHADUR , PANESAR PARMJIT S. , NANDA VIKAS , GUPTA AVTAR K. , KENNEDY JOHN F.
Published: November 2006

Osmotic dehydrations of carrot cubes in sodium chloride salt solutions at different solution concentrations, temperatures and process durations were analyzed for water loss and solute gain. The osmotically pretreated carrot cubes were further dehydrated in a cabinet dryer at 65C and were then rehydrated in water at ambient temperature for 8–10 h and analyzed for rehydration ratio, color and overall acceptability of the rehydrated product. The process was optimized for maximum water loss, rehydration ratio and overall acceptability of rehydrated product, and for minimum solute gain and shrinkage of rehydrated product by response surface methodology. The optimum conditions of various process parameters were 11% salt concentration, 30C osmotic solution temperature and process duration of 120 min.
MODEL TO PREDICT THE COOL‐DOWN CHARACTERISTICS OF VARIABLE AIR TEMPERATURE POTATO COLD STORAGE USING COMPUTATIONAL FLUID DYNAMICS
Authors: CHOURASIA M.K. , GOSWAMI T.K.
Published: November 2006

In Indian commercial potato cold storage facilities, the air temperature does not remain constant during the loading period. Also, because of stepwise loading pattern, the product loaded on different days would undergo different time‐temperature histories. Under this transient condition, the product takes longer to reach the steady state and loses more moisture of about 1.7% during 1 month of storage period. In addition, the sensible product‐cooling load is different for the product loaded on different days. In the present study, therefore, the product temperature, moisture loss and sensible product‐cooling load were predicted for the product loaded on different days under the condition of variable storage air temperature in the range of 3.5–10C and constant relative humidity of 90% using the computational fluid dynamics technique. It was found that the product loaded during the middle of loading period incurred more moisture loss than that loaded during early and latter stages of loading. However, the former case imposed more sensible product‐cooling load. The trends of temporal variation of average product temperature, moisture loss and sensible product‐cooling load depended on the day of loading of the product in the cold storage facility.
Interactive Feature Modeling for Reverse Engineering
Authors: Schreve K. , Goussard C. L. , Basson A. H. , Dimitrov D.
Published: November 2006

In feature based reverse engineering entities, or features, having higher level engineering meaning are used to approximate point data. This is in contrast to approximating the data with free form NURBS surfaces. Currently no such system is operationally available. Interactive feature based modeling tools for feature extraction, edge detection, and draft angle approximation are presented here. Several case studies demonstrate the application of these algorithms.
Multiple-beam interference with coaxial cable analogs of optical arrays
Authors: Davis Jeffrey A. , Miller Darren A. , Sánchez-López María del Mar , Cos Joaquin
Published: November 2006

We study the interference properties of N coherent oscillators by using an equivalent radiofrequency coaxial cable electrical system consisting of N coaxial cables of different lengths, a 1×N splitter, and a N×1 coupler. The typical multiple-beam interference pattern is measured for several values of N as a function of the frequency. Unlike its optical counterpart, we have to consider the attenuation of the cables. The experimental curves agree well with theory and show the characteristics of multiple-beam interference. This approach represents an inexpensive way of experimentally investigating optical arrays.
Antifungal Susceptibilities of the Species of the
Pseudallescheria boydii
Complex
Authors: Gilgado Fèlix , Serena Carolina , Cano Josep , Gené Josepa , Guarro Josep
Published: November 2006

Eighty-four isolates belonging to eight species that constitute the
Pseudallescheria boydii
complex were tested against 11 antifungal agents by using the microdilution method. There were significant differences among the species, with
Scedosporium aurantiacum
being the most resistant. In general, voriconazole was the most active drug, followed by posaconazole.
Contribution of Phagocytosis and Intracellular Sensing for Cytokine Production by
Staphylococcus aureus
-Activated Macrophages
Authors: Kapetanovic Ronan , Nahori Marie-Anne , Balloy Viviane , Fitting Catherine , Philpott Dana J. , Cavaillon Jean-Marc , Adib-Conquy Minou
Published: November 2006

Toll-like receptors (TLRs) are involved in the sensing of microbially derived compounds. We analyzed the contribution of these receptors to cytokine production by macrophages following stimulation with whole bacteria. Using knockout mice, we confirmed that the TLR4 and TLR2 contribution was predominant in the induction of tumor necrosis factor alpha and interleukin-10 by gram-negative bacteria. In contrast, the absence of TLR2 and/or TLR4 or TLR9 did not affect the response to gram-positive bacteria. In the absence of TLR2, phagocytosis was essential for cytokine production in response to heat-killed
Staphylococcus aureus
(HKSA). Because intracellular sensing was important in the absence of TLR2, we evaluated the contribution of Nod1 and Nod2, intracytoplasmic sensors of peptidoglycan-derived muropeptides, to the response to HKSA. By transfecting RAW 264.7 macrophages with dominant negative (DN) forms of Nod1 and Nod2, we showed that both molecules inhibited NF-κB activation in response to HKSA. The unexpected interference of DN Nod1 in the response of macrophages to gram-positive bacteria was confirmed with a Nod2 agonist (muramyl dipeptide) in transfection experiments with HEK293T cell. Taken together, these results show the contribution of phagocytosis and Nod molecules to the response to HKSA in macrophages and also identify possible cross talk between Nod1 and Nod2.