bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stegkrüppeln bei voll‐ und teilperforierten Trapezprofilen
Authors: Misiek Thomas , Albiez Matthias 
Published: February 2008

AbstractTrapezprofile aus Stahl oder Aluminium können am Auflager oder unter Einzellasten aufgrund ihrer Dünnwandigkeit durch Stegkrüppeln versagen. Eine aus Gründen der Schalldämpfung vorgenommene Perforation der Stege reduziert den Widerstand gegen Stegkrüppeln. Der Einfluss der Perforation kann durch Abminderung der nach DIN 18807‐1 oder DIN 18807‐6 ermittelten Tragfähigkeit mit einem Faktor Cp für vollperforierte Profile oder Ctp für teilperforierte Stege ermittelt werden.
Successful field capture techniques for free‐ranging argali sheep (Ovis ammon) in Mongolia
Authors: Kenny David , DeNicola Anthony , Amgalanbaatar Sukhiin , Namshir Zundui , Wingard Ganchimeg , Reading Richard 
Published: February 2008

AbstractArgali sheep (Ovis ammon) are the world's largest wild sheep and are threatened throughout their range in Mongolia. Little is known about the ecology of this highly cursorial species. This project was initiated to develop safe capture techniques in order to learn more about the ecology of argali in the Ikh Nartiin Chuluun Nature Reserve in southeastern Mongolia by using radiotelemetry. To our knowledge no one had ever successfully live‐caught a free‐ranging argali. We developed three techniques for capturing argali. From 2003 to 2007 we hand captured 65 argali lambs, losing one (our first capture) to maternal neglect because we stayed too long in the area and a second that was euthanized after being accidentally injured by a horse. Between 2000 and 2003 we captured six argali by darting, losing one ewe to an abdominal infection after a misplaced dart. Finally, between 2002 and 2007 we captured 32 argali by drive‐netting. We lost one ewe to over‐exertion after a long drive. The remaining 31 animals captured by drive‐netting did not appear to suffer any immediate effects (still alive in 30 days). This report will discuss the strengths and weaknesses for each of these capture techniques. Zoo Biol 27:137–144, 2008. © 2008 Wiley‐Liss, Inc.
Styles and regimes of orogenic thickening in the Peloritani Mountains (Sicily, Italy): new constraints on the tectono-metamorphic evolution of the Apennine belt
Authors: VIGNAROLI GIANLUCA , ROSSETTI FEDERICO , THEYE THOMAS , FACCENNA CLAUDIO 
Published: February 2008

AbstractThe Peloritani Mountains constitute the Sicilian portion of the Calabria–Peloritani Arc (Italy), a tectono-metamorphic edifice recording the history of the subduction–exhumation cycle during Tertiary convergence between the African and European plates. Here, we describe the kinematic and the petrological characteristics of the major shear zones bounding the lowermost continental-derived metamorphic units cropping out in the eastern portion of the Peloritani Mountains. Both meso- and micro-scale shear sense criteria indicate a top-to-the-SSE tectonic transport, during a general evolution from ductile to brittle deformation conditions. Quantitative thermobarometry on texturally equilibrated phengite–chlorite pairs crystallized along the shear bands indicates pressure of 6–8 kbar at temperatures of 360–440 °C for the structurally highest units and 3–4 kbar at 380–440 °C for the lowest ones. This documents an overall inverse-type nappe arrangement within the tectonic edifice and a transition from an Alpine- (13–18 °C km−1) to a Barrovian-type (28–36 °C km−1) geothermal gradient during the progress of the Alpine orogenic metamorphism in the Peloritani Mountains. The integration of these results allows the Peloritani Mountains to be considered as a constituent element of the Apennine orogenic domain formed during the progressive space–time transition from oceanic to continental subduction at the active convergent margin.
Lunatic fringe causes expansion and increased neurogenesis of trunk neural tube and neural crest populations
Authors: Elena De Bellard Maria , Barembaum Meyer , Arman Odette , Bronner-Fraser Marianne 
Published: February 2008

AbstractBoth neurons and glia of the PNS are derived from the neural crest. In this study, we have examined the potential function of lunatic fringe in neural tube and trunk neural crest development by gain-of-function analysis during early stages of nervous system formation. Normally lunatic fringe is expressed in three broad bands within the neural tube, and is most prominent in the dorsal neural tube containing neural crest precursors. Using retrovirally-mediated gene transfer, we find that excess lunatic fringe in the neural tube increases the numbers of neural crest cells in the migratory stream via an apparent increase in cell proliferation. In addition, lunatic fringe augments the numbers of neurons and upregulates Delta-1 expression. The results indicate that, by modulating Notch/Delta signaling, lunatic fringe not only increases cell division of neural crest precursors, but also increases the numbers of neurons in the trunk neural crest.
The bulk modulus ‐ attenuation ‐ viscosity systematics of diopside‐anorthite melts
Authors: Secco R. A. , Manghnani M. H. , Liu T.‐C. 
Published: February 2008

Ultrasonic measurements of Qp−1 and Vp for An and Di.64An.36 melts are reported in the frequency range 3 – 20 MHz and in the temperature range from melting to 1934K and 1831K5 respectively. When Qp−1 and shear viscosity are normalized to their respective liquidus temperature values, they have the same linear dependence on reciprocal homologous temperature. From the Arrhenius temperature dependence of Qp−1, the activation energies calculated for An and Di.64An.36 melts are on the order of 216 and 302 kJ/mol, respectively. Although there is insufficient data for An, the activation energy of Qp−1 for Di.64An.36 is in excellent agreement with its activation energy of viscosity.The relaxed adiabatic bulk modulus, derived from relaxed velocities, for An at 1893K is 20.4 ± 0.2 GPa and for Di.64An.36 at 1677K is 23.0 ± 0.1 GPa. These values fall into a general trend of decreasing bulk modulus with increasing Al2O3.
Measurements of condensation nuclei above the jet stream: Evidence for cross jet transport by waves and new particle formation at high altitudes
Authors: Wilson J. C. , Lai W. T. , Smith S. D. 
Published: February 2008

Condensation nuclei (CN) were used as a tracer in mid‐latitude aircraft experiments in April and May 1984 designed to study transport in the stratosphere. A very large scale, mean distribution of CN was determined for April 20 in the plane perpendicular to the jet stream using smoothed CN measurements and very large scale, mean potential vorticity isopleths. This very large scale, mean distribution was constructed to exclude the structures associated with waves of short vertical wavelengths. A second analysis was done on filtered CN data by Danielsen et al. [this issue] to produce a CN cross section which included the effects of waves having vertical wavelengths of the order of 1 to 3 km. These two analyses and the waves inferred from the meteorological and tracer data produce a self‐consistent explanation for the observed spatial distribution of CN on April 20. The very large scale, mean CN distribution was distorted by waves which had the effect of transporting air with anticyclonic properties several degrees to the cyclonic side of the jet and created a strongly layered structure in the CN distribution.The unfiltered CN data revealed short wavelength oscillations in the CN distribution at the interface between the transported anticyclonic air parcel and the adjacent cyclonic air mass. These oscillations were also seen in the ozone data, and they increase the potential for mixing along that interface. If the mixing does occur, then a wave mechanism for cross jet transport has been observed.At altitudes above about 17 km, CN mixing ratios were affected by a high altitude source of new particles.
Evidence for marine production of isoprene
Authors: Bonsang Bernard , Polle Claude , Lambert Gérard 
Published: February 2008

New data obtained in the Mediterranean Sea and Pacific Ocean show that isoprene could be produced in sea water by biological processes, leading to concentrations in the ppb range (10−9 liter of gas per liter of water).Taking into account Henry's constant for isoprene in water and the very low concentrations measured in the marine atmosphere, the superficial sea water is supersaturated in isoprene by one or two orders of magnitude. From these observations, an oceanic flux of the order of 1.2 Mt per year of isoprene can be estimated.This is a small value, as compared with the marine fluxes of the other NMHC; it is also practically negligible in the global burden of isoprene. However, because of its short lifetime in air, isoprene in remote marine atmosphere, entirely originates from superficial seawater, it could be therefore an useful tracer of marine emissions of gaseous compounds.
Night uv spectra (1100–2900Å) at mid and low latitude during a magnetic storm
Authors: Ishimoto M. , Romick G. J. , Paxton L. J. , Meng C.‐I. , Huffman R. E. 
Published: February 2008

Spectral analyses of night atmospheric emission observations from the S3‐4 satellite revealed enhanced OI 1304‐Å, OI 1356‐ Å, and OI 1640‐ Å, NI 1493‐ Å, NI 1744‐ Å and NI 12143‐Å lines and Lyman‐Birge‐Hopfield (LBH) band emissions at low magnetic latitudes. The satellite, at about 260‐km altitude, was over the region between −41° to −15° geomagnetic latitudes at7:55 UT on August 28, 1978 (Dst = −193) during the main phase of a major geomagnetic storm (Maximum Dst = −242 at 10 UT).The observed ratios of the LBH bands to the NI 1493‐Å and NI 1744‐Å line emissions are an order of magnitude lower than those produced by electron impact and are similar to laboratory measurements of heavy particle impact (H and H+) on N2. Significant precipitation of neutral O atoms, formed by charge exchange of the ring current O+ with exospheric hydrogen and oxygen, can occur when |Dst| is large. Oxygen is observed to dominate the ring current at corresponding low L‐values during a storm main phase. Consideration of these and other factors leads us to conclude that the most likely cause of the observed emissions is oxygen precipitation from the ring current.
Ulysses particle observations of the March 1991 solar flare events
Authors: Sanderson T. R. , Marsden R. G. , Heras A. M. , Wenzel K.‐P. , Anglin J. D. , Balogh A. , Forsyth R. 
Published: February 2008

We present observations of energetic ions from the COSPIN instrument on the Ulysses spacecraft at 2.5 AU during the March 1991 series of solar flare events. The intensity profiles observed during this sequence of events were affected both by the presence of interplanetary shocks and large‐scale discontinuities in the magnetic field, the low‐energy (∼1 MeV) protons being influenced mainly by the shocks and the discontinuities, and the high‐energy (∼100 MeV) protons by the discontinuities.The first shock observed at Ulysses was followed by several discontinuities and a Coronal Mass Ejection (CME) which were probably moving with the shock. Particles following this shock were prevented from propagating freely into the heliosphere by the structure moving with the shock, and were carried along with it. A second shock was followed by a region containing bi‐directional particle anisotropies. A subsequent enhancement of low‐energy particles suggests the passage of another shock. This was followed by a slow intensity decay which coincided with a second CME and where bi‐directional particle anisotropies were again observed.
Cosmogenic neon in recent lavas from the western United States
Authors: Poreda Robert J. , Cerling Thure E. 
Published: February 2008

The absolute cosmogenic production of 21Ne (21Nec) and 3He (3Hec) in olivine (Fo81) is measured for the well‐dated Tabernacle Hill flow. Values scaled to sea level and high latitude ( > 60°) are 45 atoms/g/yr for 21Nec and 109 atoms/g/yr for 3Hec for the past 17,800 years.Production rates for 21Nec are about 50% higher than the theoretical values given by Lal [1991]. A ratio of 21Nec/3Hec of 0.41 ± 0.05 is measured in olivines that have a range of 25 in cosmogenic exposure; there is no evidence of 3Hec loss in samples older than 100,000 years.Volcanic plagioclase is shown to be a suitable mineral for cosmogenic 21Nec dating of surfaces. 21Nec in co‐existing plagioclase and olivine phenocrysts have a constant ratio of 0.42 ± .04 in samples with more than 106 atoms of 21Nec. Using all of the 21Nec data and the 3Hec as a cosmic ray flux monitor, production of 21Nec in Ab36 plagioclase is calculated at 16.8 ± 1.7 atoms/g‐yr for the past 17,800 years. The production of 21Nec from 23Na is estimated at 160 ± 50 atoms/g/yr at 60° and sea level or equivalent to that on 24Mg.
Submarine basalts from the Red Sea: New Pb, Sr, and Nd isotopic data
Authors: Volker Frank , McCulloch Malcolm T. , Altherr Rainer 
Published: February 2008

High‐precision Pb isotope analyses are reported for Holocene basalts from the axial trough of the Red Sea in order to resolve the discrepancy between Pb isotope data published in two recent papers [Dupré et al., 1988; Altherr et al., 1990]. Carefully handpicked glassy rock chips were leached in strong acid prior to dissolution to minimize contamination and alteration effects. In addition, Sr and Nd isotopes were analysed from the same sample solution to obtain a complete isotopic profile along this nascent oceanic basin.Red Sea basalts show a wide range in Pb isotopes with 206Pb/204Pb ratios extending from 18.1 to 19.6. In a plot of 207Pb/204Pb versus 206Pb/204Pb, the basalts lie next to, or slightly above, the Northern Hemisphere Reference Line with Δ7/4 values between −1.5 and +3.1, in accord with the data from Dupré et al. [1988]. High Δ7/4 values (up to +12) reported by Altherr et al. [1990] are most probably due to severe sample contamination.Basalts with chemical and isotopic signatures typical for N‐type MORBs (206Pb/204Pb = 18.1–18.3; 87Sr/86Sr ≈ 0.70269; 143Nd/144 Nd ≈0.51315) occur in the central region of the Red Sea at about 21.4°N. To the North and South of this central region, Pb and Sr isotope ratios show a systematic increase accompanied by a decrease in Nd isotope ratios. N‐type MORBs from the central part of the Red Sea display Pb, Sr, and Nd isotopic signatures indistinguishable from basalts from the Carlsberg Ridge of the Indian Ocean. Thus there is no evidence that these two oceanic spreading centres tap chemically different convective systems in the asthenosphere as has been suggested previously.
stratospheric trace gas concentrations in the Arctic polar night derived by FTIR‐spectroscopy with the Moon as IR light source
Authors: Notholt J. , Neuber R. , Schrems O. , Clarmann T. V. 
Published: February 2008

In winter 1992/93 we have performed ground‐based FTIR measurements in the Arctic (79°N, 12°E) to derive column densities of stratospheric trace gases within the polar vortex. Due to the polar night the moon had to serve as infrared light source instead of the sun. It was possible to perform FTIR‐measurements for about a week around full moon. Column densities of N2O, CH4, HF, HCl, O3, NO2, HNO3 and ClONO2 have been obtained.The spectra were recorded at 0.01 cm−1 or 0.02 cm−1 resolution using MCT or InSb detectors.Measurements with an aerosol lidar performed at the same site show that polar stratospheric clouds (PSCs) appeared several times during the polar night. It seems that the concentrations of the stratospheric trace gases are strongly influenced by the occurrence of PSCs.
The melting relation of the system, iron and carbon at high pressure and its bearing on the early stage of the Earth
Authors: Hirayama Yoshiharu , Fujii Toshitsugu , Kurita Kei 
Published: February 2008

The melting relation of iron‐carbon system is studied to see how iron takes in or disgorges carbon at high pressure (up to 12GPa). The understanding on these points is closely related to the problem of the reservoir of carbon in the earth's interior. The results are: (1) Iron‐carbon system shows eutectic melting till at least 12GPa. (2) The eutectic composition is about 3 or 4 wt% of carbon, which does not vary very much with pressure. (3) The eutectic temperature slightly goes up as pressure increases at a rate of 7°C/GPa. This gradient is fairly lower than that of the melting temperature of silicates.Based on these results and other facts, the following scenario is inferred on the core formation during the early stage of the earth. Because carbon melts into iron forming eutectic system at low temperature, carbon within the accreted chondritic materials might be absorbed into iron melt near the surface of the magma ocean. The observation that the melting temperature of silicate goes up more rapidly as pressure increases than the eutectic temperature of iron‐carbon system, indicates that the temperature within the magma ocean is maintained higher than the melting temperature of iron‐carbon system. Therefore, the carbon‐bearing iron melt may sink into the deep interior of the earth without solidifying and disgorging carbon. After all, it is strongly suggested that carbon may settle with liquid iron forming core.
Spatiotemporal dynamics in oscillatory zoned magmatic plagioclase
Authors: Higman S. L. , Pearce T. H. 
Published: February 2008

This work presents a quantitative analysis of spatiotemporal patterns that form during the growth of oscillatory zoned plagioclase. These patterns were imaged using Nomarski interference contrast imaging of etched polished surfaces. Analysis of these imaged patterns yields new information and constraints on how patterns form, and consequently on how oscillatory zoned crystals may develop in magmatic systems.Utilizing mathematical techniques recently developed for the analysis of dynamical systems, we show that the irregular nature of oscillatory zoning is not compatible with random or stochastic processes. The analysis of our observations suggests that the plagioclase‐liquid system is a deterministic nonlinear system whose attractor has a relatively low dimension. Finally, comparison of our empirical results with computer models of other dynamical systems implies that as few as two variables may be sufficient to describe the dynamics of the plagioclase‐liquid system.
Results of a reconnaissance microearthquake survey of Bucaramanga, Colombia
Authors: Pennington Wayne D. , Mooney Walter D. , van Hissenhoven René , Meyer Hansjürgen , Ramirez J. E. , Meyer Robert P. 
Published: February 2008

Six University of Wisconsin portable, continuously‐recording seismographs were operated for 3½ days in late 1976 in the Eastern Cordillera of Colombia in a 200‐km‐diameter array around Bucaramanga, where there are also three permanent stations of the Instituto Geofísico de Los Andes Colombianos. Twenty‐seven microearthquakes were recorded. Most can be well located. Only one event, located along the eastern boundary of the Eastern Cordillera, is at crustal depths. At least two events, beneath the western half of the Eastern Cordillera, are 110‐115 km in depth.Twenty earthquakes are associated with the Bucaramanga nest (6.83°N, 73.12°W), at a depth of 158 ± 4 km. For these well‐recorded events, relative arrival times between stations vary by up to ± 0.3 sec, and the epicentral area is 4‐5 km in diameter. The complex character of these seismograms, compared with those from 110‐115 km depth events outside the nest, suggests either complexity in the rupture process or, more likely, multi‐pathing which originates near the source region.For the upper mantle and crust above the nest, the average values for Q are about 450 for shear waves and probably over 1,000 for compressional waves, suggesting that the rays travel through lithospheric material for their entire path. If the two events at intermediate depths outside the nest and the nest lie at the same horizon within the same slab, they define a slab that strikes N‐S and dips to the east at 33°.
A significant upper limit for the rate of formation, of OCS from the reaction of OH with CS2
Authors: Iyer R. Subramonia , Rowland F. S. 
Published: February 2008

The rate of reaction of OH with CS2 to form OCS by reaction (1) has been measured through observation of O14CS following 254 nm photolysis of mixtures of H2O2 with 14CS2. The OH concentrations have been monitored through simultaneous measurement in the same cell of either (a) the oxidation of CO to CO2, or (b) the removal of a hydrocarbon such as C3H8 or iso‐C4H10. The upper limit for the formation of OCS based on (a) corresponds to a rate constant k1 < 0.3 × 10−14 cm³ molecule−1 sec−1. Other chemical reactions in the system have led to the formation of both 14CO and 14CO2, indicating the existence of a complex combination of reactions such that the observed O14CS need not have been formed by (1).The rate of reaction (1) is sufficiently slow that it is neither an important atmospheric sink for CS2 nor an important source for atmospheric OCS. The reaction of OH with OCS has not been measured in these experiments, but by analogy with k1 it is probably not an important atmospheric sink for OCS nor an important source of SO2.
The pH of Hawaiian precipitation a preliminary report
Authors: Miller John M. , Yoshinaga Alan M. 
Published: February 2008

Daily or biweekly precipitation samples have been collected at various sites on the island of Hawaii since 1974. The elevations of the sites ranged from sea level to 3400 m. Samples were analyzed on the day of collection for pH and conductivity. Detection of major anions, such as sulfate and nitrate, were made on selected samples during the period.The pH data show a progressive increase of acidity with elevation. The sea level site averaged pH 5.2, in contrast to the sites above 2500 m, which averaged pH 4.3. It is postulated that the increase in acidity at higher levels might be explained by acidic materials, either natural or man‐made, being transported over long distances in the mid‐troposphere and being scavenged in the rain of the Hawaiian islands.
The earthquake cycle in subduction zones
Authors: Melosh H. J. , Fleitout L. 
Published: February 2008

Lithospheric plates are subducted episodically, a few meters at a time, during earthquakes. These earthquakes recur over intervals ranging from decades to centuries. Within weeks to perhaps years after such an earthquake, elastic stresses induced in the asthenosphere relax, allowing displacement and stress to propagate away from the subduction zone into the adjacent plates. Finite element modelling of this process has shown that the propagation is asymmetric, the subducted slab serves to buffer the subducting plate against extensive motion. We have constructed a simple analytic model which incorporates the effect of he subducted slab in a fundamental way. The slab's effect is modelled by a Maxwell viscoelastic element which is attached to the subducting plate. Both plates obey Elsasser's displacement propagation equations. The elastic response of the Maxwell element at first restrains the motion of the subducted plate. The plate eventually moves on the timescale of stress relaxation in the Mesosphere (hundreds to thousands of years).The model predicts that the trench moves toward the subducting plate at an average speed of one half of the convergence rate. A strong extensional pulse is propagated into the overthrust plate shortly after the earthquake, whereas the stress pulse is small in the subducting plate. Although this extension changes into compression before the next earthquake in the cycle, the period of strong extension following the earthquake may be responsible for extensional tectonic features in the back‐arc region.