bluuebunny/crossref_metadata_2025 huggingface dataset:
EDITORIAL
Authors: Gjerdingen Robert O.
Published: October 2007

Charles Burney had high hopes for Naples. As he trekked ever southward in the summer of 1770, stopping along the way at Turin, Milan, Venice, Bologna, Florence and Rome, he imagined his approach to Naples as an ascent to a musical Parnassus: ‘My visits to other places were in the way of business, for the performance of a task I had assigned myself; but I came hither animated by the hope of pleasure. And what lover of music could be in the place which had produced the two Scarlattis, Vinci, Leo, Pergolesi, Porpora, Farinelli, Jommelli, Piccinni, Traetta, Sacchini, and innumerable others of the first eminence among composers and performers, both vocal and instrumental, without the most sanguine expectations?’. The recent account of a similar pilgrimage by Jérôme de Lalande had whetted Burney’s appetite for a city the Frenchman described as ‘the principal source of Italian music, of great composers, and of excellent operas’ (Voyage d’un François en Italie, 1769). Moreover, as he progressed down the peninsula he met musician after musician with ties to that Mecca of the south. And so he wrote of his arrival ‘about five o’clock in the evening, on Tuesday, October 16’: ‘I entered this city, impressed with the highest ideas of the perfect state in which I should find practical music’. His reverie, however, was short-lived. Indeed, he quickly formed an aversion to flesh-and-blood Neapolitan vocalists, instrumentalists, their performance practices, the audiences, even the gilding in the churches – in short, most of what he
LOVE AND MUSIC IN AUGUSTAN LONDON; OR, THE ‘ENTHUSIASMS’ OF RICHARD ROACH
Authors: DIXON TOM
Published: October 2007

This article explores and contextualizes the thought of the religious author Richard Roach (1662–1730) from a musical perspective. Roach, a member of the Behmenist, millenarian Philadelphian Society in London at the turn of the eighteenth century, published little that relates directly to the subject of music, and has thus gone virtually unrecognized in this context. Nevertheless, in his more substantial religious oeuvre music emerges as a crucial component of his thought. In addition, his manuscript diaries and papers reveal their author’s interaction with some of Augustan London’s leading musical figures, and his participation in a previously unknown weekly musical meeting.

After reviewing the overall circumstances of Roach’s life and cultural milieu, the article outlines what can at present be established about his musical activities. As I demonstrate, evidence from the diaries clarifies the provenance of an early hymn collection, while other extant sources reveal an unsuspected connection between religious ‘enthusiasm’ and the reception in London of Italian opera. The integral place of music in Roach’s worldview is then related to aspects of his thought ranging from ‘spiritual gender’, eschatology and the Divine Magia to science and politics. Beyond this timely focus on a neglected individual, however, I draw attention to the continuing tendency to overlook contexts such as this one, in which music is a potentially important but not an obviously paramount ingredient. I suggest that conventional conceptions of an emerging ‘public sphere’ – secular, enlightened, rational – need to be modified to take account of supposedly marginalized, ‘enthusiastic’ religious groups such as the Philadelphians. Finally, the absorption of developing musical genres into the background of an age-old model of universal harmony is taken as an instance of the powerful historical interplay between change and continuity.
EIGHTEENTH-CENTURY POLITICS AND PATRONAGE: MUSIC AND THE REPUBLICAN REVOLUTION OF NAPLES
Authors: DELDONNA ANTHONY R.
Published: October 2007

In December 1798 the Kingdom of the Two Sicilies, with Naples as its capital, capitulated to the Republican armed forces of France under the direction of General Championnet. The establishment of the First Republic of Naples, the so-called Parthenopean Republic, was brief, lasting only until June 1799. Although fleeting, the Republic nevertheless exercised a profound effect on virtually every facet of contemporaneous society, especially music and theatre. In this essay I examine musical life during the first Republic of Naples (1798–1799), based upon surviving primary sources.

These sources include legal and civic documents, personal diaries and correspondence, employment rosters, newspapers (giornali), opera librettos and musical compositions. They illustrate the effects of the revolution on contemporary artistic practices, specifically with regard to those political and social uses of the operatic stage by the new regime that had consequences for repertory choice, production practices, theatrical management and the artists themselves. The bringing-together of these sources provides not only a detailed chronicle of contemporaneous events, but also significantly furthers present-day understanding of artistic practices during the Republic as well as providing a context for the policies enacted with the restoration of the Bourbon monarchy.
SCHUBERT AS SCHILLER’S SENTIMENTAL POET
Authors: MAK SU YIN
Published: October 2007

Schubert’s lifelong interest in literature, his close friendships with poets and his preference for lyric poetry in his prolific song settings suggest that his compositional language may be shaped as much by a literary imagination as by musical concerns. This article argues for a close correspondence between Schubert’s late instrumental style and Friedrich Schiller’s conception of the elegiac. In ‘On Naïve and Sentimental Poetry’ Schiller describes the sentimental poet as having to contend with two conflicting objects, the ideal and actuality, and to represent their opposition either satirically or elegiacally: whereas satire rails against the imperfections of present reality, elegy expresses longing for an ideal that is lost and unattainable. Paradoxically, however, the poet’s longing must take place in a flawed present; the elegiac thus projects not only a disjunction between divided worlds, but also a cyclic temporality in which memory and desire, past and future, are both entwined with the immediacy of present experience. In both Schiller and Schubert, this paradoxical temporal sensibility is often represented by patterns of returning, repetition and circularity. A close reading of Schubert’s Moment musical in A flat major, d780/2, illustrates how Schiller’s conception of the elegiac might be put into analytical practice.
A MOVABLE FEAST: THE ARIA IN THE ITALIAN LIBRETTO IN LONDON BEFORE 1800
Authors: BURDEN MICHAEL , CHOWRIMOOTOO CHRISTOPHER
Published: October 2007

The purpose of this short essay is to announce a new research project, ‘The Aria in the Italian Libretto in London before 1800’, the aim of which is to list the incipits of all the arias included in Italian-language opera and oratorio librettos printed in London before the turn of the nineteenth century. The notion that an opera libretto may not be the stable text it appears on the page to be is no news to scholars working on opera and musical theatre, who understand perfectly well the possible nature and origins of the sources they use, especially the libretto. At least one hopes they do; but in the case of the last, do they? The seductive lure of the printed page is strong, a lure which has an almost irresistible pull for scholars when there is a score to ‘match’; it becomes even stronger when those working on canonic composers stray out of their chosen territory to look for ‘contemporaneous examples’ from the works of ‘minor composers’, or when there is no thematic catalogue to provide even a basic chart with which to navigate the treacherous waters of the output of even some major eighteenth-century ones. A libretto is, after all, not ‘music’, they say – ‘that’s all very well, but why aren’t you talking about the music?’ – so why worry? Just hurry on to the matching score to identify the ‘composer’s intentions’, and all will be well.
ON BWV1080/8: BETWEEN THEORY AND PRACTICE
Authors: DEMEYERE EWALD
Published: October 2007

The application of rhetoric to music had special significance in the seventeenth century and in the first half of the eighteenth century. The discipline of classical Greek oratory, originally dealing with how to make and execute a speech, formed the basis for the rules of composition and performance, especially in German-speaking lands. During this period the influence of rhetorical principles on all parameters of music was commonplace; not only did a vast number of treatises on rhetoric in music emerge, but the central educational programme taught in the Latin schools and the universities included both musica and rhetorica among the seven artes liberales. That rhetoric was also a fundamental part of Bach’s music-making is shown by the following testimony from Johann Abraham Birnbaum (1702–1748), Professor of Poetics and Rhetoric at Leipzig: ‘He so perfectly understood the resemblance which the performance of a musical piece has in common with rhetorical art that he was listened to with the utmost satisfaction and pleasure when he discoursed of the similarity and agreement between them; but we also wonder at the skilful use he made of this in his works’.
Medizinische Geographie
Authors: Hauri
Published: October 2007

Geographische Faktoren aller Art wie Klima, Relief, Geologie aber auch Siedlungsmuster haben schon immer einen Einfluss auf die Verteilung von Krankheiten gehabt, wie dies bereits von Hippokrates festgestellt werden konnte. Die medizinische Geographie untersucht die Beziehung zwischen geographischen Faktoren und Krankheiten, wobei geographische Techniken und Konzepte auf gesundheitsrelevante Probleme angewendet werden. Besonders wichtig ist dabei die Kartierung von Krankheiten, deren Ursachen umweltbedingt sind. Daneben spielen bei der Erforschung der Beziehung zwischen geographischen Faktoren und Krankheiten epidemiologische, sozialwissenschaftliche und auch ökologische Studien eine zentrale Rolle. Um die Beziehung zwischen der räumlichen Verteilung von Krankheiten und der Umweltexposition zu verstehen, kommen in jüngerer Zeit vermehrt geographische Informationssysteme, aber auch statistische Analysemethoden zum Einsatz. Gewisse Autoren betrachten die medizinische Geographie lediglich als Hilfsdiziplin der Medizin. Da aber Mensch und Umwelt auch in Zukunft medizinische Fragestellungen prägen werden und ihnen eine wichtige Rolle bezüglich der Ausbreitung von Krankheiten, die als besiegt galten, zukommt, wird die medizinische Geographie auch in Zukunft in Zusammenhang mit medizinischen Fragestellungen eine wichtige Rolle spielen. Besonders die Reisemedizin ist als Teildisziplin der Medizin auf geographisches Wissen angewiesen, wenn es darum geht, einen Patienten zu beraten, der in ein unbekanntes Land reist, von welchem Kenntnisse über die geographische Verbreitung und Ökologie von Krankheiten notwendig sind.
« ...damit ich Dich besser sehen kann» – Photodynamische Diagnostik beim oberflächlichen Blasenkarzinom
Authors: Forster  , Wyler  , Ruszat  , Gasser  , Bachmann
Published: October 2007

Die photodynamische Diagnostik der Harnblase erlaubt es Tumoren und maligne veränderte Schleimhautareale (z.B. Carcinoma in situ) der Harnblase besser erkennen zu können. Dafür wird 5-Aminolävulinsäure oder Hexaminolävulinsäure ca. zwei Stunden vor dem Eingriff in die Blase instilliert. Die Substanzen werden besonders in veränderter Schleimhaut in der Häm-Biosynthese verstoffwechselt und es kommt dort zur Akkumulation von Protoporphyrin IX (PPIX). PPIX ist ein sehr gutes Fluorochrom, welches unter blauem Licht rot leuchtet. Bei der transurethralen Resektion der Blase können so alle verdächtigen Tumoren und Schleimhautareale vollständig entfernt werden. Dadurch wird die Tumor-Rezidivrate gesenkt und Rezidiv-Operationen und Hospitalisationen können vermieden werden.
Decompaction weakening and channeling instability in ductile porous media: Implications for asthenospheric melt segregation
Authors: Connolly J. A. D. , Podladchikov Y. Y.
Published: October 2007

We propose that a mechanical flow channeling instability, which arises because of rock weakening at high fluid pressure, facilitates segregation and transport of asthenospheric melts. To characterize the weakening effect, the ratio of the matrix viscosity during decompaction to that for compaction is treated as a free parameter R in the range 1 to 10−6. Two‐dimensional numerical simulations with this rheology reveal that solitary, vertically elongated, porosity waves with spacing on the compaction length scale δ initiate from miniscule porosity perturbations. By analogy with viscous compaction models we infer that in the absence of far‐field stress, the three‐dimensional expression of the waves is as pipe‐like structures of radius δ, a geometry that increases fluid fluxes by a factor of ∼1/R. The waves grow by draining fluid from the background porosity but leave a wake of elevated porosity that localizes subsequent flow. Wave amplitudes grow linearly with time, increasing by a factor of R−3/8 in the time required to drain the porosity a distance of ∼δ. Dissipation of gravitational potential energy by the waves has the capacity to enhance growth rates through melting. Maximum wave speeds are ∼40 times the speed of fluid flow through the unperturbed matrix. Such waves may provoke the elastic response necessary to nucleate, and localize the melt necessary to sustain, more effective transport mechanisms. The formulation introduces no melting effects and is applicable to fluid flow and localization problems in ductile porous media in general.
Calibrating infrasonic to seismic coupling using the Stardust sample return capsule shockwave: Implications for seismic observations of meteors
Authors: Edwards Wayne N. , Eaton David W. , McCausland Philip J. , ReVelle Douglas O. , Brown Peter G.
Published: October 2007

Shock waves produced by meteoroids are detectable by seismograph networks, but a lack of calibration has limited quantitative analysis of signal amplitudes. We report colocated seismic and infrasound observations from reentry of NASA's Stardust sample return capsule (SSRC) on 15 January 2006. The velocity of the SSRC (initially 12.5 km/s) was the highest ever for an artificial object, lying near the low end of the 11.2–72 km/s range typical of meteoroids. Our infrasonic/seismic recordings contain an initial N wave produced by the hypersonic shock front, followed ∼10 s later by an enigmatic series of weak, secondary pulses. The seismic signals also include an intervening dispersed wave train with the characteristics of an air‐coupled Rayleigh wave. We determine an acoustic‐seismic coupling coefficient of 7.3 ± 0.2 μm s−1/Pa. This represents an energy admittance of 2.13 ± 0.15%, several orders of magnitude larger than previous estimates derived from earthquake or explosive analogs. Theoretical seismic response was computed using in situ VP and VS measurements, together with laboratory density measurements from samples of the clay‐rich playa. Treatment of the air‐ground interface as an idealized air‐solid contact correctly predicts the initial pulse shape but underestimates its seismic amplitude by a factor of ∼2. Full‐wave synthetic seismograms simulate the air‐coupled Rayleigh wave and suggest that the secondary arrivals are higher‐order Airy phases. Part of the infrasound signal appears to arise from coupling of ground motion into the air, much like earthquake‐induced sounds.
Three‐dimensional geophysical mapping of rock alteration and water content at Mount Adams, Washington: Implications for lahar hazards
Authors: Finn Carol A. , Deszcz‐Pan Maryla , Anderson Eric D. , John David A.
Published: October 2007

Hydrothermally altered rocks, particularly if water saturated, can weaken stratovolcanoes, thereby increasing the potential for catastrophic sector collapses that can lead to far‐traveled, destructive debris flows. Evaluating the hazards associated with such alteration is difficult because alteration has been mapped on few active volcanoes and the distribution and intensity of subsurface alteration are largely unknown on any active volcano. At Mount Adams, some Holocene debris flows contain abundant hydrothermal minerals derived from collapse of the altered edifice. Intense hydrothermal alteration significantly reduces the resistivity and magnetization of volcanic rock, and therefore hydrothermally altered rocks can be identified with helicopter electromagnetic and magnetic measurements. Electromagnetic and magnetic data, combined with geological mapping and rock property measurements, indicate the presence of appreciable thicknesses of hydrothermally altered rock in the central core of Mount Adams north of the summit. We identify steep cliffs at the western edge of this zone as the likely source for future large debris flows. In addition, the electromagnetic data identified water in the brecciated core of the upper 100–200 m of the volcano. Water helps alter the rocks, reduces the effective stress, thereby increasing the potential for slope failure, and acts, with entrained melting ice, as a lubricant to transform debris avalanches into lahars. Therefore knowing the distribution of water is also important for hazard assessments. Our results demonstrate that high‐resolution geophysical and geological observations can yield unprecedented views of the three‐dimensional distribution of altered rock and shallow pore water aiding evaluation of the debris avalanche hazard.
Deciphering seasonal variations in the diet and drinking water of modern White‐Tailed deer by in situ analysis of osteons in cortical bone
Authors: Larson T. E. , Longstaffe F. J.
Published: October 2007

In situ carbon and oxygen isotope values for bioapatite were obtained from longitudinal slices of cortical bone from modern domesticated sheep and free‐range White‐Tailed deer. The analyses were obtained using an IR‐laser coupled to a GC‐IRMS interface. Ablation pits averaged 200 × 50 μm, making it possible to sample individual or small bundles of osteons. Cortical bone is remodeled along osteons throughout a mammal's life. Therefore, data at this scale can record seasonal variations in diet and drinking water during the adult stages of a mammal, whereas teeth provide may provide information about the juvenile years of a mammal. Average δ18O and δ13C values for the sheep from southwestern Ontario, Canada, were 14.0 and −16.1‰, respectively. No trend was observed in the isotopic composition of the sheep's osteons, consistent with its constant diet and water supply. The δ18O (14.2 to 16.6‰) and δ13C (−19.2 to −15.6‰) values of osteons from White‐Tailed deer from nearby Pinery Provincial Park, however, varied systematically and were negatively correlated. Oxygen isotope values of the osteons correlated well with changes in the δ18O values of the main water source for these deer: winter average, −10.7‰; summer average, −8.6‰. The variation in δ13C values of the osteons reflects changes in diet; summer diet consisted mainly of leafy C3 vegetation (−28.4‰), whereas winter diet comprised bark (−25.6‰), C4 grasses (δ13C, −12.7‰), and corn stalks and husks (−11.3‰).
Abrupt changes in atmospheric methane at the MIS 5b–5a transition
Authors: Grachev Alexi M. , Brook Edward J. , Severinghaus Jeffrey P.
Published: October 2007

New ice core analyses show that the prominent rise in atmospheric methane concentration at Dansgaard‐Oeschger event 21 was interrupted by a century‐long 20% decline, which was previously unrecognized. The reversal was found in a new ∼100‐year resolution study of methane in the GISP2 ice core, encompassing the beginning of D‐O event 21, which also corresponds to the transition from MIS 5b to 5a. Although a corresponding reversal (within age uncertainty) is observed in climate proxies measured in GISP2 ice, including δ18Oice, electrical conductivity, light scattering, and several ions, this feature has not been discussed previously. Abrupt changes in methane are paralleled by changes in δ15N of trapped air, a quantity that reflects local temperature change at Greenland summit. The reversal described here supports the hypothesis that climate can be unstable during major transitions, as was previously described for the last deglaciation.
Far plasma wake of Titan from the RPWS observations: A case study
Authors: Modolo R. , Wahlund J.‐E. , Boström R. , Canu P. , Kurth W. S. , Gurnett D. , Lewis G. R. , Coates A. J.
Published: October 2007

The Titan's plasma wake has been investigated using observations from the Radio and Plasma Wave Science (RPWS) instrument onboard the Cassini spacecraft during one Titan flyby on December 26, 2005. The Langmuir Probe and the wideband receiver suggest a strong asymmetry of the plasma wake, which is displaced from the ideal wake. Two distinct structures are identified inbound and outbound of the flyby with significantly different electron number densities (ne). The maximum electron number density reached 14 cm−3 on the Saturn side, connected to the sunlit ionosphere, while on the opposite side of Saturn observations indicate a density smaller than 2 cm−3. Other derived parameters of the Langmuir probe analysis suggest also a difference in plasma composition between the two structures, where heavy and light ions dominate the Saturn and anti‐Saturn side respectively. The total ion outflow is estimated at 2–7 × 1025 ions/s assuming a cylindrical geometry for the plasma wake.
Time variation of nonthermal escape of oxygen from Mars after solar wind dynamic pressure enhancement
Authors: Kaneda Kaori , Terada Naoki , Machida Shinobu
Published: October 2007

We investigate the nonthermal escape of oxygen from Mars due to the dissociative recombination of O2+. By combining a time‐dependent two‐stream model for the nonthermal oxygen with an MHD model of the ionosphere‐magnetosheath interaction, the response of the oxygen escape rate to time‐varying solar wind conditions is examined. Over the last few decades a number of model calculations of expected nonthermal oxygen escape have been performed, but all assumed steady state conditions. In this study we calculate the time variation of the nonthermal escape rate after enhancement of the solar wind dynamic pressure. We find that the escape rate of nonthermal oxygen increases by a factor of about two to four as the ionosphere is compressed in response to solar wind dynamic pressure enhancement. We also find that in steady states the escape rate for high ionopause altitude cases (h ∼ 600 km) is twice as large as that for low ionopause altitude cases (h ∼ 250 km) due to non‐negligible dissociative recombination above the exobase.
Causes of the reduction in uncertainty in the anthropogenic radiative forcing of climate between IPCC (2001) and IPCC (2007)
Authors: Haywood Jim , Schulz Michael
Published: October 2007

Mechanisms that drive climate change are quantified by the radiative forcing which is the perturbation to the global energy balance of the Earth/atmosphere system. These mechanisms may be of anthropogenic or natural origins and each has an associated level of scientific uncertainty. Until recently, even the sign of the anthropogenic radiative forcing has been in doubt because strong, poorly quantified negative radiative forcings such as those from aerosols act to oppose the strong, well quantified positive radiative forcings from well mixed greenhouse gases. We present an analysis of the probability distribution function of the anthropogenic radiative forcing for the individual forcing mechanisms identified by IPCC (2001) and IPCC (2007). We conclude that significant progress in reducing the uncertainty of the anthropogenic radiative forcing has been made since IPCC (2001). The single most important contributor to this conclusion appears to be the reduction in the uncertainty associated with the aerosol direct effect, followed by the provision of a best estimate for the aerosol cloud albedo indirect effect.
Ionospheric electrons in Titan's tail: Plasma structure during the Cassini T9 encounter
Authors: Coates A. J. , Crary F. J. , Young D. T. , Szego K. , Arridge C. S. , Bebesi Z. , Sittler E. C. , Hartle R. E. , Hill T. W.
Published: October 2007

We present results from the CAPS electron spectrometer obtained during the downstream flyby of Titan on 26 December 2005, which occurred during a period of enhanced plasma pressure inside the magnetosphere. The electron data show an unusual split signature with two principal intervals of interest outside the nominal corotation wake. Interval 1 shows direct evidence for ionospheric plasma escape at several RT in Titan's tail. Interval 2 shows a complex plasma structure, a mix between plasma of ionospheric and magnetospheric origin. We suggest a mechanism for plasma escape based on ambipolar electric fields set up by suprathermal ionospheric photoelectrons.
Abrupt change in tropical African climate linked to the bipolar seesaw over the past 55,000 years
Authors: Brown E. T. , Johnson T. C. , Scholz C. A. , Cohen A. S. , King J. W.
Published: October 2007

The tropics play a major role in global climate dynamics, and are vulnerable to future climate change. We present a record of East African climate since 55 ka, preserved in Lake Malawi sediments, that indicates rapid shifts between discrete climate modes related to abrupt warming (D‐O) events observed in Greenland. Although the timing of the Malawi events cannot be determined exactly, our age model implies that they occur prior to their Greenland counterparts, consistent with southward excursions of the Intertropical Convergence Zone during Greenland stadials. The magnitude of each of the events recorded in Malawi sediments corresponds to the scale of the subsequent Greenland warming. This suggests that a tropical component of climate sets a template for abrupt high northern latitude climate fluctuations associated with the bipolar seesaw.
Reversal of trend of biomass burning in the Amazon
Authors: Koren Ilan , Remer Lorraine A. , Longo Karla
Published: October 2007

We use MODIS aerosol optical depth and AVHRR fire counts over the Amazon Basin to determine whether biomass burning is increasing or decreasing over continental scales in South America. We find a significant sustained increasing trend in both the seasonal mean optical depth and fire data that begins in the year 2000 and 1998, respectively, and continues through 2005. However, there is a sharp reversal of this trend in 2006 that causes the overall trend to become less significant. The sharp decrease of biomass burning in 2006 is linked to a tri‐national policy shift first implemented in 2006. The results show how significantly human activity can affect the large scale environment.
Helium isotopes as geochemical indicators of a serpentinized fore‐arc mantle wedge
Authors: Umeda Koji , McCrank Glen F. , Ninomiya Atusi
Published: October 2007

New helium isotope data from hot springs on eastern Kyushu Island were obtained in order to elucidate the geographic distribution of 3He/4He ratios in the fore‐arc regions of southwest Japan. Systematic, regional variations in 3He/4He ratios are clearly distinguished across the fore arc from Kyushu Island (0.093–0.79 RA, where RA denotes the atmospheric 3He/4He ratio of 1.4 × 10−6), to Shikoku Island (0.17–3.6 RA) and to the Kii Peninsula (0.24–7.4 RA). The distribution of mantle helium relative to total helium reveals a close association with the geophysical evidence of a serpentinized fore‐arc mantle wedge including the occurrence of deep, nonvolcanic, low‐frequency tremors (LFTs), believed to be caused by upwardly mobile aqueous fluids derived from slab dehydration. Flux of mantle helium carried by aqueous fluids via a non serpentinized fore‐arc mantle wedge is very low on Kyushu Island where LFTs have not been detected and 3He/4He ratios are lower than the atmospheric ratio. On the other hand, hot springs above the regions where LFTs occur in the Kii Peninsula and northern Shikoku Island have high 3He/4He ratios, indicating a significant contribution of mantle helium carried by aqueous fluids via a serpentinized fore‐arc mantle wedge. The helium isotopes in hot and natural spring gases may be a useful geochemical indicator of a serpentinized fore‐arc mantle wedge, especially in areas with sparse seismic station coverage.
Modeling interplay between regional net ecosystem carbon balance and soil erosion for a crop‐pasture region
Authors: Gao Qiong , Yu Mei , Liu Yinghui , Xu Hongmei , Xu Xia
Published: October 2007

The balance between erosion‐induced soil carbon loss and the reduction in heterotrophic respiration caused by carbon removal in semiarid ecosystems that suffer from severe soil erosion is still largely uncertain. In this paper, we revised and applied a simulation model to analyze responses of ecosystem processes in the crop‐pasture belt region of northern China to impacts of soil erosion and climate shift. The revised model includes a new module that calculates runoff‐induced soil erosion and soil carbon and nutrient losses. The model was validated against long‐term field observations on plant productivity at several sites, and sediment yields of experiments with various vegetation covers and slopes. Simulation with historical climate data without considering erosion showed that the average net primary productivity (NPP), heterotrophic respiration (RHE), agricultural harvest (HAV), and net ecosystem carbon balance (NECB) were 210.1 ± 26.9, 169.8 ± 7.7, 35.9 ± 4.1, and 4.4 ± 22.5 gC m−2 a−1, respectively. In contrast, simulation with soil erosion gave an average erosion‐induced loss of soil organic carbon (ECL) of 11.0 ± 2.8 gC m−2 a−1, and decreased average NPP, RHE, and HAV by 3.3 ± 0.7, 14.5 ± 0.3, and 0.2 ± 0.0 gC m−2 a−1, respectively. Given NPP maintained by crop fertilization and irrigation for crop fields, the erosion‐induced soil carbon loss is thus counterbalanced by the decrease in heterotrophic respiration, resulting in an invariant NECB with respect to soil erosion.
Deep Brain Stimulation for Neurological Diseases
Authors: Halpern Casey H , Hurtig Howard I , Baltuch Gordon H
Published: October 2007

Deep brain stimulation (DBS) is an effective surgical therapy for well‐selected patients with advanced Parkinson disease and essential tremor. DBS may also offer promise for other neurological diseases, such as dystonia, Tourette Syndrome and epilepsy.
Denaturing Gel Electrophoresis of DNA in Alkaline Agarose Gels
Authors: Southern Edwin M
Published: October 2007

One of the simplest ways to separate DNA under denaturing conditions is to use an alkaline agarose gel. This method is not, however, suitable for RNA because it is rapidly hydrolysed in alkaline conditions. Similarly, DNA containing ribonucleotides will be nicked.
Vestibular System
Authors: Dieringer Norbert
Published: October 2007

Specialized mechanoreceptors, known as hair cells, detect and encode angular and linear components of head movements as well as the orientation of the head with respect to gravity. These signals activate stabilizing somatic and autonomic reflexes, evoke a perception of self motion and can trigger nausea and dizziness.
Sleep
Authors: Steriade M
Published: October 2007

Sleep comprises two distinct stages: rapid eye movement sleep and resting sleep.
Muscarinic Acetylcholine Receptors
Authors: Nathanson Neil M
Published: October 2007

Muscarinic acetylcholine receptors play a key role in the regulation of signal transduction in the central and peripheral nervous systems.
Plasminogen Potentiates Thrombin Cytotoxicity and Contributes to Pathology of Intracerebral Hemorrhage in Rats
Authors: Fujimoto Shinji , Katsuki Hiroshi , Ohnishi Masatoshi , Takagi Mikako , Kume Toshiaki , Akaike Akinori
Published: October 2007

Thrombin and plasmin are serine proteases involved in blood coagulation and fibrinolysis, whose precursors are circulating in blood stream. These blood-derived proteases might play important roles in the pathogenesis of intracerebral hemorrhage by acting on brain parenchymal cells. We previously reported that thrombin induced delayed neuronal injury through extracellular signal-regulated kinase (ERK)-dependent pathways. Here, we investigated potential cytotoxic actions of plasminogen, a precursor protein of plasmin, using slice cultures prepared from neonatal rat brain and intracortical microinjection model in adult rats. Although plasminogen alone did not evoke prominent neuronal injury, plasminogen caused significant neuronal injury when combined with a moderate concentration of thrombin (30 U/mL) in the cerebral cortex of slice cultures. The cortical injury was prevented by tranexamic acid and aprotinin. The combined neurotoxicity of thrombin and plasminogen was also prevented by PD98059, an inhibitor of ERK pathway, as well as by other agents that have been shown to prevent cortical injury induced by a higher concentration (100 U/mL) of thrombin alone. Extracellular signal-regulated kinase phosphorylation after plasminogen exposure was localized in cortical astrocytes. Moreover, microinjection of plasminogen in vivo potentiated thrombin-induced cortical injury, and inhibition of plasmin ameliorated hemorrhage-induced neuronal loss in the cerebral cortex. These results suggest that plasminogen/plasmin system augmenting thrombin neurotoxicity participates in hemorrhagic cortical injury.
HIV-1 Activates Proinflammatory and Interferon-Inducible Genes in Human Brain Microvascular Endothelial Cells: Putative Mechanisms of Blood—Brain Barrier Dysfunction
Authors: Chaudhuri Anathbandhu , Duan Fenghai , Morsey Brenda , Persidsky Yuri , Kanmogne Georgette D
Published: October 2007

The mechanisms underlying blood—brain barrier (BBB) dysfunction seen in human immunodeficiency virus 1 (HIV-1) infection are poorly understood; however, they are believed to be caused by interactions of human brain microvascular endothelial cells (HBMEC) with virus-infected macrophages. Using a transwell system and Affymetrix arrays, we investigated HIV-1-induced genomic changes in HBMEC after coculture with HIV-1-infected or -uninfected monocyte-derived macrophages (MDM). Differentially expressed genes were determined by linear modeling and then were grouped by hierarchical clustering. Compared to HBMEC cocultured with noninfected MDM, 184 probe sets corresponding to 84 genes were differentially expressed in HBMEC cocultured with HIV-infected MDM. Genes activated in HIV-1 MDM-exposed HBMEC included proinflammatory cytokines and chemokines, tumor necrosis factor-α-induced proteins, interferon (IFN)-inducible genes, intercellular adhesion molecule-1, transcription factors of the nuclear factor-κB family, and signal transducer and activator of transcription 1. Analysis of molecular networks and canonical pathways associated with differentially expressed genes suggest that HIV-1 causes BBB impairment by mechanisms involving inflammation, cytokine, and IFN signaling in HBMEC.
Close Coupling between Astrocytic and Neuronal Metabolisms to Fulfill Anaplerotic and Energy Needs in the Rat Brain
Authors: Serres Sébastien , Raffard Gérard , Franconi Jean-Michel , Merle Michel
Published: October 2007

Carbon metabolism in the rat brain was studied in animals anesthetized with a light dose of pentobarbital and in awake animals under morphine, which were infused with either [1-13C]glucose+acetate or glucose+[2-13C]acetate for various periods of time. Brain amino-acid enrichments in tissue extracts were determined by nuclear magnetic resonance (NMR) spectroscopy and their time evolution was analyzed by automatic fitting. Acetyl-coenzyme A C2 enrichment and ratio between pyruvate carboxylase and pyruvate dehydrogenase activity (PC/PDH) were determined from glutamate and glutamine labeling. The following results were obtained: (i) amino-acid enrichment patterns implied metabolic compartmentation and occurrence of the glutamate—glutamine cycle; (ii) kinetics of aspartate, GABA, and glutamate labeling from [1-13C]glucose and of glutamine labeling from [2-13C]acetate indicated a twofold higher metabolic activity in awake than in anesthetized rat brain; (iii) evaluation of the contributions of the astrocytic and neuronal metabolisms to glutamine synthesis in both groups of rats indicated a coupling between neuronal tricarboxylic acid (TCA) cycle, glutamate—glutamine cycle and glial TCA cycle; and (iv) analyzing the extrapolations back to time zero and the steady-state values of PC/PDH indicated a close coupling between PC activity and both astrocytic and neuronal TCA cycles. All these results suggest a cooperative-like behavior of astrocytic and neuronal metabolisms to fulfill the anabolic and energy needs linked to brain activation.
Random walks on the Comb model and its generalizations
Authors: Arkhincheev V. E.
Published: October 2007

Microscopic models with anomalous diffusion, which include the Comb model and its generalization for the finite width of the backbone, have been considered in this paper. The physical mechanisms of the subdiffusion random walks have been established. The first comes from the permanent return of the diffusing particle to the initial point of the diffusion due to “effective reducing” of the dimensionality of the considered system to the quasi-one-dimensional system. This physical mechanism has been obtained in the Comb model and in the model with a strip. The second mechanism of the subdiffusion is connected with random capture on the traps of diffusing particles and their ensuing random release from the traps. It has been shown that these different mechanisms of subdiffusion have been described by the different generalized diffusion equations of fractional order. The solutions of these different equations have been obtained, and the physical sense of the fractional order generalized equations has been discussed.
Examining the effect of chain length polydispersity on the phase behavior of polymer solutions with the statistical associating fluid theory (Wertheim TPT1) using discrete and continuous distributions
Authors: Paricaud Patrice , Galindo Amparo , Jackson George
Published: October 2007

Polymers are naturally polydisperse. Polydispersity may have a large effect on the phase behavior of polymer solutions, in particular, on the liquid-liquid phase equilibria. In this paper, we determine the cloud and shadow curves bounded by lower critical solution temperatures for a number of polymer+solvent systems where the polymer is polydisperse in terms of molecular weight (chain length). The moment method [P. Sollich, P. B. Warren, and M. E. Cates, Adv. Chem. Phys. 116, 265 (2001)] is applied with the SAFT approach to determine cloud and shadow curves with continuous Schulz-Flory distributions. It is seen that chain length polydispersity always enhances the extent of liquid-liquid phase equilibria. The predicted cloud curves obtained for continuous distributions are very similar to those obtained for simple ternary mixtures with the same polydispersity index, while the corresponding shadow curves can be very different depending on the composition of the parent distribution. The ternary phase behavior can be used to provide an understanding of the shape of the cloud and shadow curves. Regions of phase equilibria between three liquid phases are found for ternary systems when the chain length distribution is very asymmetrical; such regions are not observed for Schulz-Flory distributions even in the case of a large degree of polydispersity.
Impregnation of liquids into a laminated porous material with a high permeability contrast
Authors: Alimov M. M. , Kornev K. G.
Published: October 2007

This paper sets the physical basis for an efficient method designed to fill low permeable porous materials with liquids. Fast filling of these materials is achieved if one sandwiches a slightly permeable sample between highly permeable layers. We derived a useful engineering formula for the front speed as a function of the layer permeability and thickness. An asymptotic analysis of the two-dimensional liquid flow with moving front is performed assuming that the covering layers are much thinner than the sample thickness. It is shown that the front forms sawteeth with the tooth apexes moving along the highly permeable layers. If the surface layers are made of the same material, two sawteeth are mirror symmetric with respect to the sample midplane. The angle which they form drastically depends on the ratio of layer-to-sample permeabilities and on the ratio of skin-to-core thicknesses. The theory presented in this paper can be used to optimize the processes of impregnation of nanostructured materials.
Selective sampling of transition paths
Authors: Fu Xuebing , Yang Lijiang , Gao Yi Qin
Published: October 2007

In this short paper, we introduce an approximate method for the quick estimate of rate constants based on a simple sampling method of reactive transition paths over high energy barriers. It makes use of the previously introduced accelerated molecular dynamics (MD) simulation method to generate initial points for trajectory shooting. The accelerated MD simulations, although with the loss of real dynamics, lead to a quick calculation of thermodynamic properties and at the same time produce an ensemble of configurations with an enhanced sampling over the phase space that is more “reactive.” The forward/backward trajectory shooting as that used in the transition path sampling method is then initiated from the configurations obtained from accelerated MD simulations to generate transition paths on the original unbiased potential. This method selectively enhances sampling of successful trajectories and at the same time accelerates significantly the calculation of rate constants.
Enhancement of the Benjamin-Feir instability with dissipation
Authors: Bridges T. J. , Dias F.
Published: October 2007

It is shown that there is an overlooked mechanism whereby some kinds of dissipation can enhance the Benjamin-Feir instability of water waves. This observation is new, and although it is counterintuitive, it is due to the fact that the Benjamin-Feir instability involves the collision of modes with opposite energy sign (relative to the carrier wave), and it is the negative energy perturbations that are enhanced.
Role of nonadditive forces on the structure and properties of liquid water
Authors: Li Jianhui , Zhou Zhongwu , Sadus Richard J.
Published: October 2007

The role of nonadditive interactions on the structure and dielectric properties of water is investigated at different temperatures using molecular dynamics. A new intermolecular potential is developed which contains an ab initio description of two-body additive interactions plus nonadditive contributions from both three-body interactions and polarization. Polarization is the main nonadditive influence, resulting in improved agreement with experiment for the radial distribution function, dielectric constant, and dipole moment. A comparison is also made with other widely used intermolecular potentials. The new potential provides a superior prediction of the dielectric constant and dipole moment. It also predicts the relative contribution of hydrogen bonding better than the SPC/E potential [Berendsen et al., J. Phys. Chem. 91, 6269 (1987)].
Imaging a coupled quantum dot-quantum point contact system
Authors: Gildemeister A. E. , Ihn T. , Schleser R. , Ensslin K. , Driscoll D. C. , Gossard A. C.
Published: October 2007

We have quantitatively studied the effect of charge traps on the electrical conductance of a quantum dot and a capacitively coupled quantum point contact. Using the sharp metallic tip of a low-temperature scanning force microscope as a scanned gate, we could localize the traps. The quantum point contact served as a charge detector and allowed us to distinguish single electron charging events in several traps from charging events on the dot. We used the quantum dot to analyze the tip-induced potential quantitatively and found its shape to be independent of the voltage applied to the tip within a certain range of parameters. We estimate that the trap density is below 0.1% of the doping density, that the charging energy of a trap is three times higher than that of the quantum dot, and that the interaction energy between the quantum dot and a trap is a significant portion of the dot’s charging energy. Possibly, such charge traps are the reason for frequently observed parametric charge rearrangements.
Adsorption and thermal evolution of SO2 on Ru(0001)
Authors: Hennies F. , Föhlisch A. , Wurth W. , Feulner P. , Fink A. , Menzel D.
Published: October 2007

Using high resolution S 2p and O 1s x-ray photoelectron spectroscopies, the adsorption of SO2 and its surface bound reaction products on Ru(0001) have been investigated simultaneously while dosing SO2 and while heating the adsorbed species. SO2 is found to adsorb on Ru(0001) at 100K molecularly in two variants as well as dissociatively and to react to SO3, SO4, SO, and S with increasing coverage. After the monolayer has been saturated, SO2 adsorbs molecularly in multilayers. When heating adsorbed SO2 from 100K, SO, SO2, and SO4 decompose in a wide temperature range up to 305K. In contrast SO3 is found to be stable bound to Ru(0001) up to 300K and to disappear from the surface to below 325K. At 550K the surface remains with a saturated atomic sulfur and oxygen layer and some sulfur species in a second layer. Our quantitative analysis of the sulfur amount bound to the surface supports a simple desorption process only for SO4. All other species mainly or partly decompose on the surface.
Photoabsorption cross sections of NH3, NH2D, NHD2, and ND3 in the spectral range 110–144nm
Authors: Wu Yu-Jong , Lu Hsiao-Chi , Chen Hong-Kai , Cheng Bing-Ming , Lee Yuan-Pern , Lee L. C.
Published: October 2007

Cross sections for photoabsorption of NH3, NH2D, NHD2, and ND3 near 298K were measured in the spectral range of 110–144nm using radiation from a synchrotron. Absorption cross sections and oscillator strengths of NH3 agree satisfactorily with previous reports; those of ND3 are improved over those in a previous report, whereas those of NH2D and NHD2 are new. The oscillator strengths of transitions to D, D′, D″, F, and G states are nearly the same among all four isotopic variants, but those to D‴ and E states vary substantially. Observed absorption bands are arranged into vibrational progressions in accord with known Rydberg transitions. All progressions show a common trend of vibrational intervals increasing with vibrational quantum numbers. The Rydberg orbitals for states D(3de″), D′(4sa1′), D″(3da1′), D‴(4pe′), and E(4de″) are readily assigned with quantum defects determined in these experiments, but assignments for F(5de″) and G(6de″) are uncertain. Absorption cross sections of dissociative continua underneath discrete structures are larger for NH2D and NHD2 than for NH3 and ND3, indicating that the rate of dissociation of ammonia might increase when its symmetry is broken.
Pattern transitions induced by delay feedback
Authors: Li Qian Shu , Hu Hai Xiang
Published: October 2007

Modulated by delay feedback (DF), a reaction-diffusion system is destabilized and undergoes pattern transitions in the parametric region where the undelayed system spontaneously exhibits a bulk oscillation. By varying the feedback parameters, oscillatory hexagon superlattices and stripes, as well as stationary hexagons are observed. Meanwhile, the hexagon superlattices with different wavelengths are found under appropriate feedback parameters. It is demonstrated that, since the DF induces an instability of homogeneous limit cycle with respect to spatial perturbations, the patterns possessing the corresponding spatial modes are formed. Instead of stabilizing the system, here the DF may play a role of destabilization.
Multifractal analysis of passive tracer transport in simulated skimming and wake interference flows
Authors: Jiménez-Hornero Francisco J. , Laguna Ana M. , Giráldez Juan V. , Diz José
Published: October 2007

Multifractal turbulence formalism has been shown to be suitable for analyzing high resolution time series in the passive tracer transport when skimming and wake interference flows are developed in a water flume. A study of the empirical statistical moment scaling function for several scale ratios reveals the multifractal nature of these flow regimes. The parameter of the universal multifractal model related to the sparseness of the mean of the process is influenced by the strength of the shear layer developed over the roughness elements in the simulated flow regimes.