bluuebunny/crossref_metadata_2025 huggingface dataset:
Coronal loop seismology using multiple transverse loop oscillation harmonics
Authors: Van Doorsselaere T. , Nakariakov V. M. , Verwichte E.
Published: May 2008

TRACE observations (23/11/1998 06:35:57-06:48:43UT) in the 171 Å bandpass of an active region are studied. Coronal loop oscillations are observed after a violent disruption of the equilibrium. The oscillation properties are studied to give seismological estimates of physical quantities, such as the density scale height. A loop segment is traced during the oscillation, and the resulting time series is analysed for periodicities. In the loop segment displacement, two periods are found: 435.6±4.5 s and 242.7±6.4 s, consistent with the periods of the fundamental and 2nd harmonic fast kink oscillation. The small uncertainties allow us to estimate the density scale height in the loop to be 109 Mm, which is about double the estimated hydrostatical value of 50 Mm. The eigenfunction is used to do spatial coronal seismology, but that method does not give any conclusive results.
Attenuation of non-adiabatic oscillations in a cartesian prominence fibril
Authors: Soler R. , Oliver R. , Ballester J. L.
Published: May 2008

One of the typical features shown by observations of solar prominence oscillations is that they are quickly damped in time by one or several not well-known mechanisms. In addition, recent high resolution observations have revealed that the prominence fine structures, called fibrils, can oscillate with their own periods, independently from the rest of the prominence. The main aim of the present work is to study the attenuation of oscillations supported by a single prominence fibril. We consider an equilibrium made of a prominence plasma Cartesian slab of finite width embedded in a coronal medium, and assume non-adiabatic effects (thermal conduction, radiation losses and heating) as damping mechanisms. The magnetic field is taken uniform and parallel to the slab axis. We find that the efficiency of the non-adiabatic effects as damping mechanisms is different for each magnetoacoustic mode. The obtained values of the damping time are compatible with those observed in the case of the slow modes, but the fast modes are much less attenuated.
MHD waves at a spherical interface modelling coronal global EIT waves
Authors: Douglas M. , Ballai I.
Published: May 2008

Energetically eruptive events such as flares and coronal mass ejections (CMEs) are known to generate global waves, propagating over large distances, sometimes comparable to the solar radius. In this contribution EIT waves are modelled as waves propagating at a spherical density interface in the presence of a radially expanding magnetic field. The generation and propagation of EIT waves is studied numerically for coronal parameters. Simple equilibria allow the explanation of the coronal dimming caused by EIT waves as a region of rarified plasma created by a siphon flow.
Damping of non-isothermal hot coronal loops oscillations
Authors: Luna-Cardozo M. , Erdélyi R. , Mendoza-Briceño César A.
Published: May 2008

Here we investigate longitudinal waves in non-isothermal hot (T ≥ 5.0 MK) coronal loops. Motivated by SOHO SUMER and Yohkoh SXT observations and taking into account gravitational stratification, thermal conduction, compressive viscosity, radiative cooling, and heating, the governing equations of 1D hydrodynamics is solved numerically for standing wave oscillations along a magnetic field line. A semicircular shape is chosen to represent a coronal loop. It was found that the decay time of standing waves decreases with the increase of the initial temperature and the periods of oscillations are affected by the different initial velocities and loop lengths studied by the numerical experiments. The predicted decay times are within the range of values inferred from Doppler-shift oscillations observed by SUMER in hot coronal loops.
Concluding remarks
Authors: Benz Arnold O.
Published: May 2008

Waves in solar and stellar atmospheres have been proposed more than fifty years ago to heat the chromosphere and the corona. Their usefulness as a means to explain an important phenomenon gave wave science its initial impetus. However, since then, waves and oscillations have become a great astrophysical topic of their own. In an inhomogeneous medium, waves occur in immense variety. The theory of waves explores this complexity and highlights modes and properties that are important in stellar atmospheres. We have seen steady progress in this fundamental endeavour that has recently been accelerated through the use of numerical simulations. The discovery, three decades ago, of waves in the solar and stellar interiors and later in the corona, although at low energy levels, opened a new field: the diagnostic use of waves. Seismology of the interior has become a booming field of solar and stellar physics, and observed oscillations have been used to derive the magnetic field strength and to explore the corona.
Observational review on global waves
Authors: Banerjee D.
Published: May 2008

With multi-wavelength observations from ground and space-based instruments it has been possible to detect waves in a number of different wavelengths simultaneously and to, consequently, study their propagation properties. High-resolution wave observations combined with forward MHD modelling can give an unprecedented insight into the connectivity of the magnetized solar atmosphere, which further gives us a realistic chance to construct the structure of the magnetic field in the stellar atmosphere. This type of exploration is also termed as magnetic seismology. In this review I will focus on global waves, like EIT waves. I will also address the possibility of finding out the properties of magnetic structures while studying the interaction of global waves with coronal loops. A Promising new way to probe stellar atmosphere is to use our knowledge of coronal seismology on the Sun and to apply it to more distant stars. It will also enable us to measure properties such as the lengths of loops linked with stellar flares and the strengths of coronal magnetic fields on stars. In the last part I will review the current status of the stellar coronal seismology.
What Can We Do to Help and Understand Survivors of Suicide in Hong Kong?
Authors: Wong Paul W.C. , Chan Wincy S.C. , Beh Philip S.L.
Published: May 2008

Survivors of suicide or people bereaved by suicide are underresearched and underserviced. This report contains preliminary data, collected from a psychological autopsy study, which examines the characteristics of suicide survivors in Hong Kong. This paper considers the preliminary data currently available and attempts to suggest a way forward toward understanding and help for this underrecognized group of individuals in Hong Kong.
An Analysis of Parent-Female Adolescent Relationships in Female Adolescent Suicides
Authors: Bilgin Mehmet , Cenkseven Fulya , Satar Salim
Published: May 2008

This study analyzed Turkish female adolescent-family relations, which is believed to be one of the significant factors in female adolescents' suicide attempts, from a multidimensional perspective. The Parent-Adolescent Relationship Inventory, a multidimensional evaluation tool based on the behavioral family-system approach was used as a research tool. The inventory consists of the concepts and techniques of behavioral theory, family system theory, and cognitive theory in parent-adolescent' problems and conflicts. Based on these theories, the parent-adolescent relations inventory (PARQ), involves three main dimensions: problem solving and communication skills, cognitive/internalized beliefs, and functions and structures in family systems. There are two forms of the inventory, the adolescent form and the parent form. Only the adolescent form of PARQ, including 284 items, was used in this research. The inventory also consists of 16 subscales. It was adapted into Turkish by Eryüksel (1996) . The subjects of the study were 52 female adolescents who had attempted suicide and were taken to the Emergency Department of The Faculty of Medicine in Çukurova University, and 52 normal female adolescents from two different secondary schools at the southern province in Turkey. The age range of the clinical and normal groups were 14–18 ([Formula: see text] = 16). The results of the study revealed that the general stress level of female adolescents who attempted suicide is higher than those of normal groups. The examination of family structures of these female adolescents made it clear that mothers were the mediator between fathers and adolescents. It was also observed that both mothers and fathers shared many somatic concerns.
The Development of a Short Form of the Sensitivity to Punishment and Sensitivity to Reward Questionnaire
Authors: Cooper Andrew , Gomez Rapson
Published: May 2008

The Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ) has been proposed as a measure of the behavioral approach system (BAS) and behavioral inhibition system (BIS). Previous research with the SPSRQ has highlighted potential problems with the factor structure of the measure and individual item properties. The aim of the current studies was to use factor analytic and item response theory (IRT) methods to examine the psychometric properties of the SPSRQ. A further aim was to develop a short version of the SPSRQ. In Study 1, 393 adult participants completed the SPSRQ. The results from this study highlighted problems with the factor structure and item properties that had been noted in previous research. On this basis, a short form of the measure was proposed. In Study 2, the short form of the SPSRQ was tested with an independent sample (N = 327). These analyses suggested the short form of the SPSRQ had an improved factor structure, good item properties, and acceptable reliability.
Validation of Ozone Monitoring Instrument nitrogen dioxide columns
Authors: Celarier E. A. , Brinksma E. J. , Gleason J. F. , Veefkind J. P. , Cede A. , Herman J. R. , Ionov D. , Goutail F. , Pommereau J.‐P. , Lambert J.‐C. , van Roozendael M. , Pinardi G. , Wittrock F. , Schönhardt A. , Richter A. , Ibrahim O. W. , Wagner T. , Bojkov B. , Mount G. , Spinei E. , Chen C. M. , Pongetti T. J. , Sander S. P. , Bucsela E. J. , Wenig M. O. , Swart D. P. J. , Volten H. , Kroon M. , Levelt P. F.
Published: May 2008

We review the standard nitrogen dioxide (NO2) data product (Version 1.0.), which is based on measurements made in the spectral region 415–465 nm by the Ozone Monitoring Instrument (OMI) on the NASA Earth Observing System‐Aura satellite. A number of ground‐ and aircraft‐based measurements have been used to validate the data product's three principal quantities: stratospheric, tropospheric, and total NO2 column densities under nearly or completely cloud‐free conditions. The validation of OMI NO2 is complicated by a number of factors, the greatest of which is that the OMI observations effectively average the NO2 over its field of view (minimum 340 km2), while a ground‐based instrument samples at a single point. The tropospheric NO2 field is often very inhomogeneous, varying significantly over tens to hundreds of meters, and ranges from <1015 cm−2 over remote, rural areas to >1016 cm−2 over urban and industrial areas. Because of OMI's areal averaging, when validation measurements are made near NO2 sources the OMI measurements are expected to underestimate the ground‐based, and this is indeed seen. Further, we use several different instruments, both new and mature, which might give inconsistent NO2 amounts; the correlations between nearby instruments is 0.8–0.9. Finally, many of the validation data sets are quite small and span a very short length of time; this limits the statistical conclusions that can be drawn from them. Despite these factors, good agreement is generally seen between the OMI and ground‐based measurements, with OMI stratospheric NO2 underestimated by about 14% and total and tropospheric columns underestimated by 15–30%. Typical correlations between OMI NO2 and ground‐based measurements are generally >0.6.
North Atlantic Deep Water collapse triggered by a Southern Ocean meltwater pulse in a glacial climate state
Authors: Trevena J. , Sijp W. P. , England M. H.
Published: May 2008

It is generally accepted that surface freshwater anomalies in the Southern Ocean drive increases in North Atlantic Deep Water (NADW) formation via a bipolar density see‐saw. We find that a Southern Ocean freshwater pulse of comparable magnitude to meltwater pulse 1A, shuts down, instead of strengthens, NADW in a glacial climate simulation. Unlike the modern‐day simulation, the glacial experiment is associated with a more fragile North Atlantic thermohaline circulation, whereby freshwater anomalies that propagate into the North Atlantic are able to dominate the bipolar density see‐saw. Meltwater pulses over the North Atlantic and subsequent NADW shut down are often invoked to explain cold ‘Heinrich Events’ appearing in the paleoclimate record. Our results suggest that triggers for NADW collapse may also originate from the southern hemisphere in glacial epochs. Once NADW collapses, North Pacific Deep Water develops, consistent with a North Pacific/North Atlantic see‐saw triggered from the Southern Ocean.
Inflammatory Response to a High‐fat, Low‐carbohydrate Weight Loss Diet: Effect of Antioxidants
Authors: Peairs Abigail T. , Rankin Janet W.
Published: May 2008

The objective of this study was to test the hypothesis that the inflammatory response to a high‐fat, low‐carbohydrate weight loss diet (HF) we previously observed was due to oxidative stress. Nineteen overweight subjects (BMI > 27 kg/m2) were randomly assigned to either an antioxidant supplement (AS) (1 g vitamin C/800 IU vitamin E) or a placebo (P) group and provided with a HF for 7 days. Fasted pre‐ and post serum samples were measured for markers of inflammation (C‐reactive protein (CRP), interleukin‐6 (IL‐6), and monocyte chemoattractant protein‐1 (MCP‐1)), oxygen radical absorbance capacity (ORAC), and glucose, whereas urine was measured for oxidative stress (8‐epi‐prostaglandin‐F2α (8‐epi)). HF resulted in significant reductions in weight (−3.2%), glucose (−18.7%), and MCP‐1 (−15%) (all P < 0.01), with no difference between groups. There was a trend for a differential effect between groups for CRP as it decreased 32% in the AS group but increased 50% for P (P = 0.076). Inverse correlations were noted between initial values and changes in several inflammatory and oxidative stress markers, including CRP (r = −0.501), 8‐epi (r = −0.863), and ORAC (r = −0.546) (all P < 0.05). It was concluded that weight loss on a short‐term HF caused reduction of some but not all markers of inflammation. A role for oxidative stress in causing inflammation was not confirmed; however, longer term diet‐controlled studies are necessary to further explore the trend for a differential response in CRP with antioxidant supplementation.
Surface-plasmon circuitry
Authors: Ebbesen Thomas W. , Genet Cyriaque , Bozhevolnyi Sergey I.
Published: May 2008

Electromagnetic waves at the surface of a metal have the enormous bandwidth of a light pulse and can be channeled into circuit components smaller than the diffraction limit.
Effect of soil wetting conditions on seal formation, runoff, and soil loss in arid and semiarid soils—a review
Authors: Ben-Hur Meni , Lado Marcos
Published: May 2008

Soil surface sealing is one of the main causes for low infiltration rate (IR) and high runoff and soil loss under raindrop impact conditions in arid and semiarid regions. Many studies have focused on the effects of soil properties on seal formation under fast wetting conditions. However, in the field, soils can be exposed to different wetting conditions, before an intense rainfall event, which can affect the role of the soil properties on seal formation. The present paper reviews the effects of different initial wetting conditions and their interactions with soil properties on seal formation, IR, runoff, and soil loss in smectitic soils. Fast wetting of soil causes aggregate slaking, which enhances seal formation, runoff, and soil loss under rainfall, mainly in soils with > 40% clay content. An increase in clay content of the soil increases aggregate strength, but at the same time increases the slaking forces. Hence, in soils with low clay content (<40%) and low aggregate stability, raindrop impact alone was sufficient to break down the aggregates and to develop a seal. In contrast, in soils with > 40% clay content and high aggregate stability, slaking plays an important role in aggregate breakdown and seal formation. An increase of raindrop kinetic energy, from 8 to 15.9 kJ/m3, decreased the effect of the slaking forces on seal formation and runoff. It was suggested that the effects of raindrop kinetic energy and of the slaking forces on aggregate disintegration and seal formation are complementary. An increase in soil exchangeable sodium percentage (ESP), from 0.9 to 20.4%, decreased the effect of slaking forces on seal formation and runoff production under rainfall with 15.9 kJ/m3 kinetic energy. Probably, increasing the ESP increased the soil dispersivity, and therefore diminished the effect of the slaking forces on aggregate disintegration and seal formation. Aging (the time since wetting) of soil increased the stability of soil structure, decreased the seal formation, maintained high IR, and diminished soil loss amounts. These effects of soil aging depend on both the prewetting rate of the soil and soil texture.
What's the point of the type III secretion system needle?
Authors: Blocker Ariel J. , Deane Janet E. , Veenendaal Andreas K. J. , Roversi Pietro , Hodgkinson Julie L. , Johnson Steven , Lea Susan M.
Published: May 2008

Recent work by several groups has significantly expanded our knowledge of the structure, regulation of assembly, and function of components of the extracellular portion of the type III secretion system (T3SS) of Gram-negative bacteria. This perspective presents a structure-informed analysis of functional data and discusses three nonmutually exclusive models of how a key aspect of T3SS biology, the sensing of host cells, may be performed.
Folding of a donor–acceptor polyrotaxane by using noncovalent bonding interactions
Authors: Zhang Wenyu , Dichtel William R. , Stieg Adam Z. , Benítez Diego , Gimzewski James K. , Heath James R. , Stoddart J. Fraser
Published: May 2008

Mechanically interlocked compounds, such as bistable catenanes and bistable rotaxanes, have been used to bring about actuation in nanoelectromechanical systems (NEMS) and molecular electronic devices (MEDs). The elaboration of the structural features of such rotaxanes into macromolecular materials might allow the utilization of molecular motion to impact their bulk properties. We report here the synthesis and characterization of polymers that contain π electron-donating 1,5-dioxynaphthalene (DNP) units encircled by cyclobis(paraquat-
p
-phenylene) (CBPQT
4+
), a π electron-accepting tetracationic cyclophane, synthesized by using the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The polyrotaxanes adopt a well defined “folded” secondary structure by virtue of the judicious design of two DNP-containing monomers with different binding affinities for CBPQT
4+
. This efficient approach to the preparation of polyrotaxanes, taken alongside the initial investigations of their chemical properties, sets the stage for the preparation of a previously undescribed class of macromolecular architectures.
Unlocking evidence of early diet from tooth enamel
Authors: Humphrey Louise T. , Dean M. Christopher , Jeffries Teresa E. , Penn Malcolm
Published: May 2008

Recent developments in microspatial analysis of enamel chemistry provide the resolution needed to reconstruct detailed chronological records of an individual's early life history. Evidence of nutritional history, residential mobility, and exposure to heavy metals can potentially be retrieved from archaeological and even fossil teeth. Understanding the pattern and timing of incorporation of each trace element or stable isotope into enamel is crucial to the interpretation of the primary data. Here, we use laser ablation inductively coupled plasma mass spectrometry and ArcGIS software to map variation in calcium-normalized strontium intensities across thin sections of enamel from exfoliated deciduous teeth. Differences in calcium-normalized strontium intensities across each tooth reflect variation in tooth mineralization, implying that sampling location must be taken into account in interpreting results. Chronologically consistent shifts in calcium-normalized strontium intensities in teeth from children with known nursing histories reflect the onset and duration of breastfeeding and the introduction of nonmaternal sources of food. This tool is likely to be valuable for studying weaning and nursing behavior in the past. The distribution of normalized strontium intensities presented here is consistent with a model for the differential incorporation of strontium and calcium into enamel during the secretory and maturational phases of formation.
Single-molecule nonequilibrium periodic Mg
2+
-concentration jump experiments reveal details of the early folding pathways of a large RNA
Authors: Qu Xiaohui , Smith Glenna J. , Lee Kang Taek , Sosnick Tobin R. , Pan Tao , Scherer Norbert F.
Published: May 2008

The evolution of RNA conformation with Mg
2+
concentration ([Mg
2+
]) is typically determined from equilibrium titration measurements or nonequilibrium single [Mg
2+
]-jump measurements. We study the folding of single RNA molecules in response to a series of periodic [Mg
2+
] jumps. The 260-residue catalytic domain of RNase P RNA from
Bacillus stearothermophilus
is immobilized in a microfluidic flow chamber, and the RNA conformational changes are probed by fluorescence resonance energy transfer (FRET). The kinetics of population redistribution after a [Mg
2+
] jump and the observed connectivity of FRET states reveal details of the folding pathway that complement and transcend information from equilibrium or single-jump measurements. FRET trajectories for jumps from [Mg
2+
] = 0.01 to 0.1 mM exhibit two-state behavior whereas jumps from 0.01 mM to 0.4 mM exhibit two-state unfolding but multistate folding behavior. RNA molecules in the low and high FRET states before the [Mg
2+
] increase are observed to undergo dynamics in two distinct regions of the free energy landscape separated by a high barrier. We describe the RNA structural changes involved in crossing this barrier as a “hidden” degree of freedom because the changes do not alter the detected FRET value but do alter the observed dynamics. The associated memory prevents the populations from achieving their equilibrium values at the end of the 5- to 10-sec [Mg
2+
] interval, thereby creating a nonequilibrium steady-state condition. The capability of interrogating nonequilibrium steady-state RNA conformations and the adjustable period of [Mg
2+
]-jump cycles makes it possible to probe regions of the free energy landscape that are infrequently sampled in equilibrium or single-jump measurements.
ES cell pluripotency and germ-layer formation require the SWI/SNF chromatin remodeling component BAF250a
Authors: Gao Xiaolin , Tate Peri , Hu Ping , Tjian Robert , Skarnes William C. , Wang Zhong
Published: May 2008

ATP-dependent chromatin remodeling complexes are a notable group of epigenetic modifiers that use the energy of ATP hydrolysis to change the structure of chromatin, thereby altering its accessibility to nuclear factors. BAF250a (ARID1a) is a unique and defining subunit of the BAF chromatin remodeling complex with the potential to facilitate chromosome alterations critical during development. Our studies show that ablation of BAF250a in early mouse embryos results in developmental arrest (about embryonic day 6.5) and absence of the mesodermal layer, indicating its critical role in early germ-layer formation. Moreover, BAF250a deficiency compromises ES cell pluripotency, severely inhibits self-renewal, and promotes differentiation into primitive endoderm-like cells under normal feeder-free culture conditions. Interestingly, this phenotype can be partially rescued by the presence of embryonic fibroblast cells. DNA microarray, immunostaining, and RNA analyses revealed that BAF250a-mediated chromatin remodeling contributes to the proper expression of numerous genes involved in ES cell self-renewal, including Sox2, Utf1, and Oct4. Furthermore, the pluripotency defects in BAF250a mutant ES cells appear to be cell lineage-specific. For example, embryoid body-based analyses demonstrated that BAF250a-ablated stem cells are defective in differentiating into fully functional mesoderm-derived cardiomyocytes and adipocytes but are capable of differentiating into ectoderm-derived neurons. Our results suggest that BAF250a is a key component of the gene regulatory machinery in ES cells controlling self-renewal, differentiation, and cell lineage decisions.
High blood pressure arising from a defect in vascular function
Authors: Michael Simon K. , Surks Howard K. , Wang Yuepeng , Zhu Yan , Blanton Robert , Jamnongjit Michelle , Aronovitz Mark , Baur Wendy , Ohtani Kenichi , Wilkerson Michael K. , Bonev Adrian D. , Nelson Mark T. , Karas Richard H. , Mendelsohn Michael E.
Published: May 2008

Hypertension, a major cardiovascular risk factor and cause of mortality worldwide, is thought to arise from primary renal abnormalities. However, the etiology of most cases of hypertension remains unexplained. Vascular tone, an important determinant of blood pressure, is regulated by nitric oxide, which causes vascular relaxation by increasing intracellular cGMP and activating cGMP-dependent protein kinase I (PKGI). Here we show that mice with a selective mutation in the N-terminal protein interaction domain of PKGIα display inherited vascular smooth muscle cell abnormalities of contraction, abnormal relaxation of large and resistance blood vessels, and increased systemic blood pressure. Renal function studies and responses to changes in dietary sodium in the PKGIα mutant mice are normal. These data reveal that PKGIα is required for normal VSMC physiology and support the idea that high blood pressure can arise from a primary abnormality of vascular smooth muscle cell contractile regulation, suggesting a new approach to the diagnosis and therapy of hypertension and cardiovascular diseases.
COI1 is a critical component of a receptor for jasmonate and the bacterial virulence factor coronatine
Authors: Katsir Leron , Schilmiller Anthony L. , Staswick Paul E. , He Sheng Yang , Howe Gregg A.
Published: May 2008

Jasmonate (JA) is a lipid-derived hormone that regulates diverse aspects of plant immunity and development. An amino acid-conjugated form of JA, jasmonoyl–isoleucine (JA–Ile), stimulates binding of the F-box protein coronatine-insensitive 1 (COI1) to, and subsequent ubiquitin-dependent degradation of, jasmonate ZIM domain (JAZ) proteins that repress transcription of JA-responsive genes. The virulence factor coronatine (COR), which is produced by plant pathogenic strains of
Pseudomonas syringae
, suppresses host defense responses by activating JA signaling in a COI1-dependent manner. Although previous data indicate that COR acts as a molecular mimic of JA–Ile, the mechanism by which JA–Ile and COR are perceived by plant cells remains unknown. Here, we show that interaction of tomato COI1 with divergent members of the JAZ family is highly specific for JA–Ile and structurally related JA conjugates and that COR is ≈1,000-fold more active than JA–Ile in promoting this interaction
in vitro
. JA–Ile competes for binding of COR to COI1–JAZ complexes, demonstrating that COR and JA–Ile are recognized by the same receptor. Binding of COR to the COI1–JAZ complex requires COI1 and is severely impaired by a point mutation in the putative ligand-binding pocket of COI1. Finally, we show that the C-terminal region of JAZ3 containing the highly conserved Jas motif is necessary and sufficient for hormone-induced COI1–JAZ interaction. These findings demonstrate that COI1 is a critical component of the JA receptor and that COR exerts its virulence effects by functioning as a potent agonist of this receptor system.
Structural basis for NKG2A/CD94 recognition of HLA-E
Authors: Kaiser Brett K. , Pizarro Juan Carlos , Kerns Julie , Strong Roland K.
Published: May 2008

The NKG2x/CD94 (x = A, C, E) natural killer-cell receptors perform an important role in immunosurveillance by binding to HLA-E complexes that exclusively present peptides derived from MHC class I leader sequences, thereby monitoring MHC class I expression. We have determined the crystal structure of the NKG2A/CD94/HLA-E complex at 4.4-Å resolution, revealing two critical aspects of this interaction. First, the C-terminal region of the peptide, which displays the most variability among class I leader sequences, interacts entirely with CD94, the invariant component of these receptors. Second, residues 167–170 of NKG2A/C account for the ≈6-fold-higher affinity of the inhibitory NKG2A/CD94 receptor compared to its activating NKG2C/CD94 counterpart. These residues do not contact HLA-E or peptide directly but instead form part of the heterodimer interface with CD94. An evolutionary analysis across primates reveals that whereas CD94 is evolving under purifying selection, both NKG2A and NKG2C are evolving under positive selection. Specifically, residues at the CD94 interface have evolved under positive selection, suggesting that the evolution of these genes is driven by an interaction with pathogen-derived ligands. Consistent with this possibility, we show that NKG2C/CD94, but not NKG2A/CD94, weakly but specifically binds to the CMV MHC-homologue UL18. Thus, the evolution of the NKG2x/CD94 family of receptors has likely been shaped both by the need to bind the invariant HLA-E ligand and the need to avoid subversion by pathogen-derived decoys.
The Riddle of Hume's Treatise
Authors: Russell Paul
Published: May 2008

Although it is widely recognized that David Hume's A Treatise of Human Nature (1739‐40) belongs among the greatest works of philosophy, there is little agreement about the correct way to interpret his fundamental intentions. Among almost all commentators it is an established orthodoxy that skepticism and naturalism are the two dominant themes in this work. The difficulty has been, however, that Hume's skeptical arguments and commitments appear to undermine and discredit his naturalistic ambition to contribute to “the science of man”—a schism that appears to leave his entire project broken‐backed. The solution to this riddle depends on challenging another, closely related, point of orthodoxy: namely, that before Hume published the Treatise he removed almost all material concerned with problems of religion. This book argues, contrary to this view, that irreligious aims and objectives are fundamental to the Treatise and account for its underlying unity and coherence. Hume's basic anti‐Christian aims and objectives serve to shape and direct both his skeptical and naturalistic commitments. When Hume's arguments are viewed from this perspective we can not only solve puzzles arising from his discussion of various specific issues, we can also explain the intimate and intricate connections that hold his entire project together. The irreligious interpretation provides a comprehensive and fresh account of the nature of Hume's fundamental aims and ambitions in the Treatise. It also presents a radically different picture of the way in which Hume's project was rooted in the debates and controversies of his own time, placing the Treatise in an irreligious or anti‐Christian philosophical tradition that includes Hobbes, Spinoza, and their freethinking followers. Considered in these terms, Hume's Treatise constitutes the crowning achievement of the Radical Enlightenment.
3 Religious Philosophers and Speculative Atheists
Authors: Russell Paul
Published: May 2008

Hume's early critics strongly associated the skepticism of the Treatise with “atheistic” or anti‐Christian intentions. Moreover, they took Clarke's philosophy to be a particularly obvious and prominent target of Hume's battery of skeptical arguments, and present Hume as a freethinking, “minute philosopher” in the school of Hobbes, Spinoza, and Collins (i.e. Clarke's “atheistic” opponents). Scholars have generally dismissed these reactions and responses to the Treatise as coming from bigoted and narrow‐minded critics who lacked either the ability or the will to understand Hume's philosophy. The truth is, however, that these early reactions to the Treatise are entirely consistent with a proper understanding of the wider debate between the “religious philosophers” and “speculative atheists,” which was the dominant philosophical debate throughout the century that preceded the publication of the Treatise. This chapter documents and describes the major figures and contours of this crucial debate.
10 The Argument a Priori and Hume's “Curious Nostrum”
Authors: Russell Paul
Published: May 2008

Although most philosophers would agree with the suggestion that Hume's treatment of the problem of causation “is the center‐piece of the Treatise” (or, at least, of Book I), they also generally hold that Hume's views on causation in the Treatise are of little or no direct relevance to problems of natural religion. In contrast with this, many of Hume's early critics interpreted his views on causation as involving an “atheistic” or irreligious attack on the argument a priori—particularly as defended by Clarke and his followers. This chapter argues that Hume was well aware that his most distinguished adversaries had used Lucretius's (atheistic) maxim “nothing can come from nothing” to defend the cause of “superstition.” In opposition to this, Hume abandoned Lucretius's maxim and embraced its direct opposite: “any thing may produce any thing.” This “curious nostrum” served as Hume's principal weapon in his battle to discredit all efforts to use demonstrative reason to prove the existence of God.
14 Immateriality, Immortality, and the Human Soul
Authors: Russell Paul
Published: May 2008

Even commentators who have explicitly argued that the Treatise has little to say on issues of religion generally accept that Hume's discussion of the immateriality of the soul contains an obvious irreligious message. This chapter's aim, therefore, is not to labor this point (i.e. that Hume's views about the soul, immaterial substance, and personal identity are of irreligious significance), but rather to indicate the specific way in which Hume's arguments on this subject are related to the main debate between theists and atheists during the late seventeenth and early eighteenth centuries. These observations show the way in which Hume's arguments on this subject are intimately connected with his wider irreligious aims and objectives throughout the Treatise.
17 Morality without Religion
Authors: Russell Paul
Published: May 2008

According to the irreligious interpretation, there are two key claims that Hume seeks to establish in the Treatise in respect of morality. The first is that Hume defends the “autonomy of morality” in relation to religion. The foundations of moral and political life, he holds, rest with our human nature , not with the doctrines and dogmas of (Christian) religion. Closely connected with this issue, Hume also aims to show that “speculative atheism” does not imply “practical atheism” or any kind of “moral licentiousness.” Taken together, these two components of Hume's moral system constitute a defence and interpretation of “virtuous atheism.”
4 “Spectatorial Lust”
Authors: Erlmann Veit
Published: May 2008

The chapter describes the performances of the African Choir in England, focusing on the intersection of the emerging commodity aesthetics with race and gender. Situated at the heart of the conflicted construction of the metropolis and the colony, these performances highlighted the close interconnections between visual consumption and the ever widening contours of the global imagination of both colonizers and colonized.
5 Symbols of Inclusion and Exclusion
Authors: Erlmann Veit
Published: May 2008

One of the key items on the program of the African Choir was the “Great Hymn”, composed in the 1820s by Ntsikana Gaba, one of the first Xhosa Christian converts. Ntsikana's composition has been subject to numerous reworkings, which reveal the ambiguity at the heart of the colonial project. The reception of the “Great Hymn” by the British public, likewise, highlights the growing tensions between the liberal premises of the “civilizing mission” and the emerging jingoist climate of the last decade of the 19th century.
12 Dream Journeys
Authors: Erlmann Veit
Published: May 2008

This chapter discusses the making of Bhekizizwe Joseph Shabalala — founder and lead singer of Ladysmith Black Mambazo — in two works: a biography authored by two black South African journalists and “Journey of Dreams”, a documentary shot in 1988 by David Lister. Both blend discourses of authenticity and international stardom and thus serve as important vehicles of self-fashioning in the interstices of the global music industry.
5 Eastern and Western Elements in the Irish Monastic Prayer of the Hours
Authors: Jeffery Peter
Published: May 2008

The Divine Office of the early Irish church is one of the more recondite subjects in the study of Western liturgical history, and cannot be studied without looking at the Eastern Christian liturgical influences. Although most surviving Irish liturgical books are fragmentary and the liturgical reforms of the Carolingian period swept away the Irish liturgy and consequently most direct evidence that could help us interpret these fragments, some Irish material related to the structure of the Divine Office in a few Gallican centers exists but has not yet been fully investigated. This chapter outlines some of the major directions in which a new investigation based on this material will lead, and reconstructs the basic structure of the medieval Irish Office.
8 The Cluniac Processional of Solesmes
Authors: Huglo Michel
Published: May 2008

The processional is a portable book in small format containing the chants for processions, as well as processional chant for Sundays and feast days. It is not an official book but a practical book and is of comparatively recent origin. Over 1,000 MS processionals falling into nine categories survive today, and these have been recently catalogued by Michel Huglo. F-SO MS Réserve 28, is an 11th-century processional from a small monastery in southern France affiliated with the Benedictine monastery of Cluny. A historical sketch of the MS processional in general introduces a description and inventory of this source.
10 Office Compositions from St. Gall
Authors: Möller Hartmut
Published: May 2008

Some of the earliest chant MSS from St. Gall include the Offices for the two primary saints of the region, Gallus and Othmar. These sources are D-W MS Guelf. 17.5. Aug. 4o (890-920), and GB-Lbl MS Add. 21170 (c.920). The Offices of both saints were also copied around the year 1000 in the Antiphoner of Hartker. Sources such as these allow us to glimpse at first hand how music and texts for new Offices were created in the 10th and 11th centuries in St. Gall., adapting older materials to new circumstances. Discussion of these two Offices incorporates different emphases, depending upon the nature of the materials.
CHAPTER 1. SCHUMANN AND SCHUBERT'S “IMMORTAL” PIANO TRIO IN E FLAT, D. 929
Authors: Daverio John
Published: May 2008

This chapter argues that Schumann's Piano Quartet in E flat is situated at a crossroads. On the one hand, it offers the listener a compelling — and strikingly original — synthesis of earlier models and practices. While its structural underpinnings hearken to Schubert, its intense motivicism and rhythmic urgency suggest a Beethovenian source. The contrapuntal tour de force of its closing pages points back even further still, to the fugues of J. S. Bach. On the other hand, the work looks well into the future: the chains of cascading thirds that run through its final paragraphs would become a staple of Brahms's musical vocabulary.
CHAPTER 5 THE FOLDED FAN
Authors: Daverio John
Published: May 2008

The practice of cryptography as a viable medium for Schumann's and Brahms' aural embodiments of Clara has been ruled out. Thus, how they attempted to capture the image of Clara in tone remains unknown. The fan is presented as a symbol of the bittersweet mixture of imagination and remembrance implicit in the erotic experience. The photograph — a gateway to the “optical unconscious” is also identified as a symbol of revelation. And since the photograph and the fan alike are receptacles for deeply buried memories, this family of motifs embraces the totality of relations between the lover and the object of his or her affections. What we hear in the opening movement of Schumann's Fantasie (Op. 17) and the Adagio of Brahms's D-minor Piano Concerto — to name only two of the better-known “Clara” pieces — is an attempt to imbue the musical surface with the quality of a consciousness gripped by a deep preoccupation with a beloved object, an endeavor that lends to so many of the works of Schumann and Brahms the texture of a folded and unfolding fan. This chapter furthers explores the significance of this metaphor and its attendant motifs for an understanding of Schumann's and Brahms's embodiment of Clara in tone.
4 SINGING PRAISES TO THE LORD
Authors: Glixon Jonathan E.
Published: May 2008

This chapter examines the issue of paid singers of polyphony. First used in the middle of the 15th century, these men were also brothers of the scuole grandi for which they sang. They were paid relatively small fees for services at funerals and in processions, where laude were sung (these two tasks were sometimes assigned to different groups). These singers were not especially reliable, and discipline problems were common. In the 1490s, some scuole began to employ, on an occasional basis, professional singers from the chapel of San Marco. The question of repertory and the employment of wind and string instrument players and organists are also addressed.
5 THE BEST IN THE CITY
Authors: Glixon Jonathan E.
Published: May 2008

This chapter focuses on the salaried musicians of the six scuole grandi during their most active period, 1500-1650. The singers, usually four or five in each ensemble for processions, were increasingly drawn from the ducal chapel and important monastic choirs, and were paid an annual salary. Financial considerations and government restrictions sometimes reduced the number and prestige of singers. The scuole also paid lower salaries to groups of lower status singers to sing at funerals. Some scuole briefly employed wind bands for processions, but much more common were ensembles of stringed instruments, at first a mixed ensemble of lute, harp, and lira, and then, from 1530, a homogeneous ensemble of bowed instruments, a violin band, with four to six members. Some of the scuole also built and maintained organs and hired organists, while several employed choirs of priests for liturgical functions.
8 PROCESSION, VESPERS, SONGS, AND ORGAN
Authors: Glixon Jonathan E.
Published: May 2008

This chapter discusses the earliest musical activities at the hundreds of smaller confraternities known as scuole piccole. It provides an overview of the variety of scuole piccole and their histories. As early as the 14th century, piffari appeared in the records of the scuole, and beginning in the 16th century, some began to spend considerable sums for singers and instrumentalists for their annual feast day, and occasionally for Holy Week. Some scuole, particularly the parish-based Holy Sacrament confraternities, built organs and employed organists. The confraternity of the Florentine community in Venice, unlike the other scuole, practiced communal singing of laude.
11 CONCLUSIONS
Authors: Glixon Jonathan E.
Published: May 2008

This chapter provides a brief final overview of the role of both scuole grandi and scuole piccole in the musical life of Venice.
The Propertarian Counter‐Argument
Authors: Netanel Neil Weinstock
Published: May 2008

Some scholars and policy makers claim that an expansive, proprietary copyright not only imposes merely trivial speech burdens but, indeed, represents the best means for resolving the tension between copyright and free speech. As Paul Goldstein forcefully puts it: to extend copyright “into every corner where consumers derive value from literary and artistic works” is the “best prescription for connecting authors to their audiences.”A broad, proprietary copyright, Goldstein argues, would thus “promote political as well as cultural diversity, ensuring a plenitude of voices, all with the chance to be heard.” This chapter takes on that “propertarian” counter‐argument. It demonstrates that broad copyrights do not, in fact, facilitate expressive diversity. It does so on the basis of copyright economics and by distinguishing between product differentiation and expressive diversity.
CHAPTER THREE CONCEPTUAL MODELS AND THEORIES
Authors: Zbikowski Lawrence M.
Published: May 2008

This chapter focuses on conceptual models and theories. Jeanne Bamberger's research on children's representations of musical structure are analyzed, in particular her study of one specific eight-year-old boy. The part played by categorization and cross-domain mapping in the conceptual models involving this this boy used to come to terms with a musical environment is shown. How these models are combined to form a theory of music and how this theory changes in response to changes in the task at hand are also discussed. This close-up glimpse of the structure and role of conceptual models and theories leads to a more generalized characterization of these knowledge structures, which is linked to work on similar structures in artificial intelligence, cognitive anthropology, ethnomusicology, and developmental psychology. The chapter then returns to music theory and explores the role of conceptual models and theories (that is, theories framed relative to a cognitive perspective) in analyses by Jean-Philippe Rameau and Heinrich Schenker, two of the best-known music theorists of the last three hundred years.
CHAPTER 1 The Lion Stalks America
Authors: Lott R. Allen
Published: May 2008

America's first encounter with a bona fide piano virtuoso was provided by the colorful Austrian pianist Leopold de Meyer (1816-83), who had just achieved fame in Paris and other western European capitals. Unknown in America, De Meyer resorted to outlandish publicity to gain attention, a technique rampant at the time and frequently denounced as humbug. De Meyer made his American debut at New York's Park Theatre on 20 October 1845, and appeared there for two weeks on theatrical bills before giving his own grand concerts in New York's Tabernacle and later in Boston. De Meyer performed his own music, including opera fantasias typical of the time as well as pieces inspired by his exotic travels: the Marche marocaine, which emphasized a dense chordal texture and bravura passages, became his signature work.
CHAPTER 11 Wieniawski
Authors: Lott R. Allen
Published: May 2008

The violinist Henryk Wieniawski, though at first in Rubinstein's shadow, soon developed his own following appreciative of his pure tone and phenomenal technique. Rubinstein's other assisting artists, the soprano Louise Liebhart and the contralto Louise Ormeny, were not as well received. Besides concerto appearances with orchestra, Rubinstein also performed in a series of chamber music concerts in New York and at a concert of the New York Philharmonic. Rubinstein's association with the Steinway firm was both musically and socially beneficial.