bluuebunny/crossref_metadata_2025 huggingface dataset:
IP3 receptors: some lessons from DT40 cells
Authors: Taylor Colin W. , Rahman Taufiq , Tovey Stephen C. , Dedos Skarlatos G. , Taylor Emily J. A. , Velamakanni Saroj
Published: September 2009

Summary:  Inositol‐1,4,5‐trisphosphate receptors (IP3Rs) are intracellular Ca2+ channels that are regulated by IP3 and Ca2+ and are modulated by many additional signals. These properties allow them to initiate and, via Ca2+‐induced Ca2+ release, regeneratively propagate Ca2+ signals evoked by receptors that stimulate formation of IP3. The ubiquitous expression of IP3R highlights their importance, but it also presents problems when attempting to resolve the behavior of defined IP3R. DT40 cells are a pre‐B‐lymphocyte cell line in which high rates of homologous recombination afford unrivalled opportunities to disrupt endogenous genes. DT40‐knockout cells with both alleles of each of the three IP3R genes disrupted provide the only null‐background for analysis of homogenous recombinant IP3R. We review the properties of DT40 cells and consider three areas where they have contributed to understanding IP3R behavior. Patch‐clamp recording from the nuclear envelope and Ca2+ release from intracellular stores loaded with a low‐affinity Ca2+ indicator address the mechanisms leading to activation of IP3R. We show that IP3 causes intracellular IP3R to cluster and re‐tune their responses to IP3 and Ca2+, better equipping them to mediate regenerative Ca2+ signals. Finally, we show that DT40 cells reliably count very few IP3R into the plasma membrane, where they mediate about half the Ca2+ entry evoked by the B‐cell antigen receptor.
Calcium influx and signaling in cytotoxic T‐lymphocyte lytic granule exocytosis
Authors: Pores‐Fernando Arun T. , Zweifach Adam
Published: September 2009

Summary: Cytotoxic T lymphocytes (CTLs) kill targets by releasing cytotoxic agents from lytic granules. Killing is a multi‐step process. The CTL adheres to a target, allowing its T‐cell receptors to recognize antigen. This triggers a signal transduction cascade that leads to the polarization of the microtubule cytoskeleton and granules towards the target, followed by exocytosis that occurs specifically at the site of contact. As with cytokine production by helper T cells (Th cells), target cell killing is absolutely dependent on Ca2+influx, which is involved in regulating both reorientation and release. Current evidence suggests that Ca2+influx in CTLs, as in Th cells, occurs via depletion‐activated channels. The molecules that couple increases in Ca2+to reorientation are unknown. The Ca2+/calmodulin‐dependent phosphatase calcineurin, which plays a critical role in cytokine production by Th cells, is also involved in lytic granule exocytosis, although the relevant substrates remain to be identified and calcineurin activation is only one Ca2+‐dependent step involved. There are thus striking similarities and important differences between Ca2+signals in Th cells and CTLs, illustrating how cells can use similar signal transduction pathways to generate different functional outcomes.
Formation of STIM and Orai complexes: puncta and distal caps
Authors: Barr Valarie A. , Bernot Kelsie M. , Shaffer Meredith H. , Burkhardt Janis K. , Samelson Lawrence E.
Published: September 2009

Summary:  In the last few years, great progress has been made in understanding how stromal interacting molecule 1 (STIM1), a protein containing a calcium sensor that is located in the endoplasmic reticulum, and Orai1, a protein that forms a calcium channel in the plasma membrane, interact and give rise to store‐operated calcium entry. Pharmacological depletion of calcium stores leads to the formation of clusters containing STIM and Orai that appear to be sites for calcium influx. Similar puncta are also produced in response to physiological stimuli in immune cells. In T cells engaged with antigen‐presenting cells, clusters containing STIM and Orai accumulate at the immunological synapse. We recently discovered that in activated T cells, STIM1 and Orai1 also accumulate in cap‐like structures opposite the immune synapse at the distal pole of the cell. Both caps and puncta are long‐lived stable structures containing STIM1 and Orai1 in close proximity. The function of puncta as sites of calcium influx is clear. We speculate that the caps may provide a secondary site of calcium entry. Alternatively, they may serve as a source of preformed channel complexes that move to new immune synapses as T cells repeatedly engage antigen‐presenting cells.
Structurally delineating stromal interaction molecules as the endoplasmic reticulum calcium sensors and regulators of calcium release‐activated calcium entry
Authors: Stathopulos Peter B. , Ikura Mitsuhiko
Published: September 2009

Summary:  The endoplasmic reticulum (ER) lumen stores a crucial source of calcium (Ca2+) maintained orders of magnitude higher than the cytosol for the activation of a plethora of cellular responses transmitted in health and disease by a mutually efficient and communicative exchange of Ca2+ between compartments. A coordination of the Ca2+ signal is evident in the development of Ca2+ release‐activated Ca2+ (CRAC) entry, vital to lymphocyte activation and replenishing of the ER Ca2+ stores, where modest decreases in ER luminal Ca2+ induce sustained increases in cytosolic Ca2+ sourced from steadfast extracellular Ca2+ supplies. While protein sensors that transduce Ca2+ signals in the cytosol such as calmodulin are succinctly understood, comparative data on the ER luminal Ca2+ sensors is only recently coming to light with the discovery that stromal interaction molecules (STIMs) sense variations in ER stored Ca2+ levels in the functional regulation of plasma membrane Orai proteins, the major component of CRAC channel pores. Drawing from data on the role of STIMs in the modulation of CRAC entry, this review illustrates the structural features that delimit the functional characteristics of ER Ca2+ sensors relative to well known cytoplasmic Ca2+ sensors.
Mechanistic view on domains mediating STIM1–Orai coupling
Authors: Fahrner Marc , Muik Martin , Derler Isabella , Schindl Rainer , Fritsch Reinhard , Frischauf Irene , Romanin Christoph
Published: September 2009

Summary:  Calcium (Ca2+) entry into non‐excitable cells is mainly carried by store‐operated channels, which serve essential functions ranging from regulation of transcription to cell growth. The best‐characterized store‐operated current, initially discovered in T lymphocytes and mast cells, is the Ca2+ release‐activated Ca2+ (CRAC) current. The search for the molecular components of the CRAC channel has recently identified stromal interaction molecule 1 (STIM1) as the Ca2+ sensor in the endoplasmic reticulum (ER) and Orai1 as the CRAC channel pore. ER store depletion results in formation of STIM1 puncta that trigger Ca2+ influx via Orai1 channels. This review covers the role of domains within STIM1 and Orai and enlightens their function in the STIM1/Orai coupling process. Moreover, a molecular interpretation focuses on interactions between cytosolic portions of STIM1 and Orai together with a mechanistic view on the loss of function of the SCID (severe combined immunodeficiency)‐linked Orai1 R91W mutant channel. The architecture of the selectivity filter of Orai channels is finally elucidated based on permeation properties of Orai pore mutants.
ORAI1 and STIM1 deficiency in human and mice: roles of store‐operated Ca2+ entry in the immune system and beyond
Authors: Feske Stefan
Published: September 2009

Summary:  Store‐operated Ca2+ entry (SOCE) is a mechanism used by many cells types including lymphocytes and other immune cells to increase intracellular Ca2+ concentrations to initiate signal transduction. Activation of immunoreceptors such as the T‐cell receptor, B‐cell receptor, or Fc receptors results in the release of Ca2+ ions from endoplasmic reticulum (ER) Ca2+ stores and subsequent activation of plasma membrane Ca2+ channels such as the well‐characterized Ca2+ release‐activated Ca2+ (CRAC) channel. Two genes have been identified that are essential for SOCE: ORAI1 as the pore‐forming subunit of the CRAC channel in the plasma membrane and stromal interaction molecule‐1 (STIM1) sensing the ER Ca2+ concentration and activating ORAI1‐CRAC channels. Intense efforts in the past several years have focused on understanding the molecular mechanism of SOCE and the role it plays for cell functions in vitro and in vivo. A number of transgenic mouse models have been generated to investigate the role of ORAI1 and STIM1 in immunity. In addition, mutations in ORAI1 and STIM1 identified in immunodeficient patients provide valuable insight into the role of both genes and SOCE. This review focuses on the role of ORAI1 and STIM1 in vivo, discussing the phenotypes of ORAI1‐ and STIM1‐deficient human patients and mice.
The molecular physiology of CRAC channels
Authors: Prakriya Murali
Published: September 2009

Summary:  The Ca2+release‐activated Ca2+ (CRAC) channel is a highly Ca2+‐selective store‐operated channel expressed in T cells, mast cells, and various other tissues. CRAC channels regulate critical cellular processes such as gene expression, motility, and the secretion of inflammatory mediators. The identification of Orai1, a key subunit of the CRAC channel pore, and STIM1, the endoplasmic reticulum (ER) Ca2+ sensor, have provided the tools to illuminate the mechanisms of regulation and the pore properties of CRAC channels. Recent evidence indicates that the activation of CRAC channels by store depletion involves a coordinated series of steps, which include the redistributions of STIM1 and Orai1, direct physical interactions between these proteins, and conformational changes in Orai1, culminating in channel activation. Additional studies have revealed that the high Ca2+ selectivity of CRAC channels arises from the presence of an intrapore Ca2+ binding site, the properties of which are finely honed to occlude the permeation of the much more prevalent Na+. Structure‐function studies have led to the identification of the potential pore‐binding sites for Ca2+, providing a firm framework for understanding the mechanisms of selectivity and gating of the CRAC channel. This review summarizes recent progress in understanding the mechanisms of CRAC channel activation, pore properties, and modulation.
Ca2+‐NFATc1 signaling is an essential axis of osteoclast differentiation
Authors: Negishi‐Koga Takako , Takayanagi Hiroshi
Published: September 2009

Summary:  Osteoclasts are unique, multinucleated giant cells that decalcify and degrade the bone matrix. They originate from hematopoietic cells and their differentiation is dependent on a tumor necrosis factor (TNF) family cytokine, receptor activator of nuclear factor‐κB (NF‐κB) ligand (RANKL), as well as macrophage‐colony stimulating factor (M‐CSF). Recent studies have unveiled the precise molecular mechanism underlying osteoclastogenesis. In particular, the discovery of nuclear factor of activated T cells c1 (NFATc1), the master regulator of osteoclastogenesis, has proven to be a breakthrough in this field. NFATc1 is activated by Ca2+ signaling induced by the activation of the immunoglobulin‐like receptor signaling associated with immunoreceptor tyrosine‐based activation motif (ITAM)‐harboring adapters. The long‐lasting Ca2+ oscillation, which is evident during osteoclastogenesis, may ensure the robust induction of NFATc1 through an autoamplification mechanism. Thus, intracellular Ca2+ is a critical attribute of osteoclastogenic signaling. In addition, osteoclasts are exposed to a very high extracellular Ca2+ concentration ([Ca2+]o) in the bone microenvironment and respond to the change in [Ca2+]o by increasing the intracellular Ca2+, which regulates diverse cellular functions. Investigation of the molecular mechanisms underlying the regulation of intracellular Ca2+ dynamics may open up new directions for therapeutic strategies in bone disease.
B‐lymphocyte calcium inFlux
Authors: King Leslie B. , Freedman Bruce D.
Published: September 2009

Summary:  Dynamic changes in cytoplasmic calcium concentration dictate the immunological fate and functions of lymphocytes. During the past few years, important details have been revealed about the mechanism of store‐operated calcium entry in lymphocytes, including the molecular identity of calcium release‐activated calcium (CRAC) channels and the endoplasmic reticulum (ER) calcium sensor (STIM1) responsible for CRAC channel activation following calcium depletion of stores. However, details of the potential fine regulation of CRAC channel activation that may be imposed on lymphocytes following physiologic stimulation within an inflammatory environment have not been fully addressed. In this review, we discuss several underexplored aspects of store‐operated (CRAC‐mediated) and store‐independent calcium signaling in B lymphocytes. First, we discuss results suggesting that coupling between stores and CRAC channels may be regulated, allowing for fine tuning of CRAC channel activation following depletion of ER stores. Second, we discuss mechanisms that sustain the duration of calcium entry via CRAC channels. Finally, we discuss distinct calcium permeant non‐selective cation channels (NSCCs) that are activated by innate stimuli in B cells, the potential means by which these innate calcium signaling pathways and CRAC channels crossregulate one another, and the mechanistic basis and physiologic consequences of innate calcium signaling.
Context dependency of relationships between biodiversity and ecosystem functioning is different for multiple ecosystem functions
Authors: Geert Hiddink Jan , Wynter Davies Thomas , Perkins Matthew , Machairopoulou Margarita , Neill Simon P.
Published: September 2009

Increasing concern over the loss of biodiversity has led to attempts to quantify relationships between biodiversity and ecosystem functioning. While manipulative investigations have accumulated substantial evidence to support the notion that decreasing biodiversity can be detrimental to the functioning of ecosystems, recent investigations have identified the potential importance of physical processes in moderating biodiversity – ecosystem function relationships at larger geographical scales. In this study, the relationship between the genus richness of benthic macro‐invertebrates and five measures of ecosystem functioning (macrofaunal biomass, depth of the apparent redox discontinuity, fluxes of ammonium and NOxand the abundance of nematodes) was determined over a large scale wave‐induced bed shear stress gradient on the seabed of the northern Irish Sea. Ecosystem functioning was significantly correlated to genus richness for four out of five ecosystem functions. However, wave stress moderated the genus richness – ecosystem functioning relationship for only one of the ecosystem functions; genus richness had a positive effect on the depth of the apparent redox discontinuity in the sediment at high wave stress but not at low wave stress. These results indicate that the effects of biodiversity on some ecosystem functions may be sufficiently strong to generate patterns in ecosystems where other factors are also affecting ecosystem processes, but that the biodiversity–ecosystem function relationship for can be dependent on environmental conditions for specific ecosystem functions.
Reversed effects of grazing on plant diversity: the role of below‐ground competition and size symmetry
Authors: May Felix , Grimm Volker , Jeltsch Florian
Published: September 2009

Grazing is known as one of the key factors for diversity and community composition in grassland ecosystems, but the response of plant communities towards grazing varies remarkably between sites with different environmental conditions. It is generally accepted that grazing increases plant diversity in productive environments, while it tends to reduce diversity in unproductive habitats (grazing reversal hypothesis). Despite empirical evidence for this pattern the mechanistic link between modes of plant–plant competition and grazing response at the community level still remains poorly understood. Root‐competition in particular has rarely been included in theoretical studies, although it has been hypothesized that variations in productivity and grazing regime can alter the relative importance of shoot‐ and root‐competition. We therefore developed an individual‐based model based on plant functional traits to investigate the response of a grassland community towards grazing. Models of different complexity, either incorporating only shoot competition or with distinct shoot‐ and root‐competition, were used to study the interactive effects of grazing, resource availability, and the mode of competition (size‐symmetric or asymmetric). The pattern predicted by the grazing reversal hypothesis (GRH) can only be explained by our model if shoot‐ and root‐competition are explicitly considered and if size asymmetry of above‐ and symmetry of below‐ground competition is assumed. For this scenario, the model additionally reproduced empirically observed plant trait responses: erect and large plant functional types (PFTs) dominated without grazing, while frequent grazing favoured small PFTs with a rosette growth form. We conclude that interactions between shoot‐ and root‐competition and size symmetry/asymmetry of plant–plant interactions are crucial in order to understand grazing response under different habitat productivities. Our results suggest that future empirical trait surveys in grassland communities should include root traits, which have been largely ignored in previous studies, in order to improve predictions of plants’ responses to grazing.
Smart, smarter, smartest: foraging information states and coexistence
Authors: Olsson Ola , Brown Joel S.
Published: September 2009

Animals possess different abilities to gain and use information about the foraging patches they exploit. When ignorant of the qualities of encountered patches, a smart forager should leave all patches after the same amount of fixed search time. A smarter forager can be Bayesian by using information on cumulative harvest and time spent searching a patch to better inform its patch‐departure decision. The smartest forager has immediate and continuous knowledge about patch quality, and can make a perfect decision about when to leave each patch. Here we let each of these three strategies harvest resources from a slowly regenerating environment. Eventually a steady‐state distribution of prey among patches arises where the environment‐wide resource renewal just balances the environment‐wide harvest of the foragers. The fixed time forager creates a distribution with the highest mean and highest variance of patch qualities, followed by the Bayesian and the prescient in that order. The less informed strategies promote distributions with both more resources and more exploitable information than the more informed strategies. While it is true that a better‐informed strategy will always out‐perform a less well‐informed, its increase in performance may not compensate it for any costs associated with being better informed. We imagine that the fixed time strategy may be least expensive and the prescient strategy most expensive in terms of sensory organs and associated assess and respond capabilities. To consider competition between such strategies with varying costs, we introduced a single individual of each of the strategies into the environments created by populations of the other strategies. There are threshold costs associated with the better‐informed strategy such that it can or cannot outcompete a less‐informed strategy. However, over a relatively narrow range of foraging costs, less‐informed and better‐informed strategies will coexist. Furthermore, for the prescient and the Bayesian strategies, some combinations of foraging costs produce alternate stable states – whichever strategy establishes first remains safe from invasion by the other.
Complexity in relationships between antioxidants and individual life‐history parameters in a seabird and a songbird
Authors: Cohen Alan A. , Mauck Robert A. , Wheelwright Nathaniel T. , Huntington Charles E. , McGraw Kevin J.
Published: September 2009

Selection on physiological traits is thought to mediate the evolution of individual life‐history parameters like reproduction, longevity, and the tradeoffs between them, but almost nothing is known about the relationships between physiological and life‐history parameters in the wild. Antioxidants are strong candidates to correlate with life histories because they play a critical role in preventing free radical damage to macromolecules, and many types are involved in sexual signaling and embryo provisioning. Here for the first time we present data on associations between serum antioxidant measures (antioxidant capacity and concentrations of uric acid, vitamin E and carotenoids) and indices of reproductive rate and age in two bird species. After controlling for age, 36% of the variation in hatching rate in Leach's storm‐petrels Oceanodroma leucorhoa was accounted for by a negative association with antioxidant capacity. Age was negatively associated with uric acid levels. Savannah sparrows Passerculus sandwichensis showed no association between antioxidant capacity and fledging rate, but serum β‐carotene levels were weakly positively associated with fledging rate. Because antioxidant levels are known to vary markedly within individuals over time, detection of associations between long‐term measures of reproduction and instantaneous antioxidant levels suggests strong (though not necessarily causal) relationships. Relationships between antioxidants and life histories appeared to differ in sparrows and storm‐petrels though, likely due to variation in diet, ecology, and life‐history evolution in these distantly related species.
Phenotypic integration may constrain phenotypic plasticity in plants
Authors: Gianoli Ernesto , Palacio‐López Kattia
Published: September 2009

Phenotypic plasticity is essential for plant adaptation to changing environments but some factors limit its expression, causing plants to fail in producing the best phenotype for a given environment. Phenotypic integration refers to the pattern and magnitude of character correlations and it might play a role as an internal constraint to phenotypic plasticity. We tested the hypothesis that phenotypic integration – estimated as the number of significant phenotypic correlations between traits – constrains phenotypic plasticity of plants. The rationale is that, for any phenotypic trait, the more linked with other traits it is, the more limited is its range of variation. In the perennial species Convolvulus chilensis (Convolvulaceae) and Lippia alba (Verbenaceae) we determined the relationship between phenotypic plasticity to relevant environmental factors – shading for C. chilensis and drought for L. alba– and the magnitude of phenotypic integration of morphological and biomass allocation traits. In C. chilensis plants, plasticity to shading of a given trait decreased with the number of significant correlations that it had with the other traits. Likewise, the characters that showed greater plasticity to experimental drought in L. alba plants had fewer significant phenotypic correlations with other characters. We report a novel limit to phenotypic plasticity of plants by showing that the phenotypic trait architecture may constrain their plastic, functional responses to the environment.
Marathon of eponyms: 5 Ehlers–Danlos syndrome
Authors: Scully C , Langdon J , Evans J
Published: September 2009

The use of eponyms has long been contentious, but many remain in common use, as discussed elsewhere (Editorial: Oral Diseases. 2009: 15; 185). The use of eponyms in diseases of the head and neck is mainly in specialties dealing with medically compromised individuals (paediatric dentistry, special care dentistry, oral and maxillofacial medicine, oral and maxillofacial pathology, oral and maxillofacial radiology and oral and maxillofacial surgery) and particularly by hospital‐centred practitioners. This series has selected some of the more recognized relevant eponymous conditions and presents them alphabetically. The information is based largely on data available from MEDLINE and a number of internet websites as noted below: the authors would welcome any corrections. This document summarizes data about Ehlers–Danlos syndrome.
Adjuvant topical therapy with a cannabinoid receptor agonist in facial postherpetic neuralgia
Authors: Phan Ngoc Quan , Siepmann Dorothee , Gralow Ingrid , Ständer Sonja
Published: September 2009

Background: Postherpetic neuralgia is a frequent adverse event in herpes zoster patients and difficult to treat. Conventional analgetic therapy often fails to reduce the burning pain transmitted by unmyelinated nerve fibers. These nerves express cannabinoid receptors which exert a role in modulation of nociceptive symptoms. Therefore, topical therapy with cannabinoid receptor agonist seems likely to suppress local burning pain.

Patients and methods: In an open‐labeled trial, 8 patients with facial postherpetic neuralgia received a cream containing the cannabinoid receptor agonist N‐palmitoylethanolamine. The course of symptoms was scored with the visual analog scale.

Results: 5 of 8 patients (62.5 %) experienced a mean pain reduction of 87.8 %. Therapy was tolerated by all patients. No unpleasant sensations or adverse events occurred.

Conclusions: Topical cannabinoid receptor agonists are an effective and well‐tolerated adjuvant therapy option in postherpetic neuralgia.
Pycnogonid‐cnidarian trophic interactions in the deep Monterey Submarine Canyon
Authors: Braby Caren E. , Pearse Vicki B. , Bain Bonnie A. , Vrijenhoek Robert C.
Published: September 2009

Abstract. Whale carcasses, sunken wood, and cold seeps provide organically enriched oases in the food‐limited deep‐sea benthos. At three such enriched habitats in Monterey Bay, CA, at a depth of nearly 3000 m, we observed pycnogonids (sea spiders) of at least two species, Colossendeis gigas and C. japonica, feeding on sea anemones that were commonly found there. Submersible remotely operated vehicles provided direct observations of feeding, as well as high definition video and photographic images. We recorded the co‐occurrence of both pycnogonids and prey anemones during ten of 12 visits during 2002–2006. Anemones and pycnogonids were conspicuously more abundant at these oases than in the surrounding benthos. The sedentary anemone Anthosactis pearseae was attached directly to whalebones while the pom‐pom anemone, Liponema brevicornis, was found resting on soft sediment, rolling in benthic currents, or accumulating where these currents were disrupted by topography, as at whale falls, wood falls, and clam fields. Both pycnogonid species were observed feeding on these anemones, either as predators or as micropredators.
Fitting orbits to tidal streams with proper motions
Authors: Eyre Andy , Binney James
Published: September 2009

The Galaxy's stellar halo seems to be a tangle of disrupted systems that have been tidally stretched out into streams. Each stream approximately delineates an orbit in the Galactic force-field. In the first paper in this series, we showed that all six phase-space coordinates of each point on an orbit can be reconstructed from the orbit's path across the sky and measurements of the line-of-sight velocity along the orbit. In this paper, we complement this finding by showing that the orbit can also be reconstructed if we know proper motions along the orbit rather than the radial velocities. We also show that accurate proper motions of stream stars would enable distances to be determined to points on the stream that are independent of any assumption about the Galaxy's gravitational potential. Such ‘Galactic parallaxes’ would be as fundamental as conventional trigonometric parallaxes, but measurable to distances ∼70 times further.
Can magnetic fields be detected during the inspiral of binary neutron stars?
Authors: Giacomazzo Bruno , Rezzolla Luciano , Baiotti Luca
Published: September 2009

Using accurate and fully general-relativistic simulations we assess the effect that magnetic fields have on the gravitational-wave emission produced during the inspiral and merger of magnetized neutron stars. In particular, we show that magnetic fields have an impact after the merger, because they are amplified by a Kelvin–Helmholtz instability, but also during the inspiral, most likely because the magnetic tension reduces the stellar tidal deformation for extremely large initial magnetic fields, B0≳ 1017G. We quantify the influence of magnetic fields by computing the overlap, , between the waveforms produced during the inspiral by magnetized and unmagnetized binaries. We find that for any realistic magnetic field strength B0≲ 1014G the overlap during the inspiral is and is quite insensitive to the mass of the neutron stars. Only for unrealistically large magnetic fields like B0≃ 1017G the overlap does decrease noticeably, becoming at our resolutions for stars with baryon masses Mb≃ 1.4/1.6M⊙, respectively. Because neutron stars are expected to merge with magnetic fields ∼108–1010G and because present detectors are sensitive to , we conclude that it is very unlikely that the present detectors will be able to discern the presence of magnetic fields during the inspiral of neutron stars.
An accretion disc origin for the ‘X-ray broad-line region’ in 1H0707-495
Authors: Blustin A. J. , Fabian A. C.
Published: September 2009

We use a 380-ks X-ray Multi-Mirror Mission–Newton (XMM–Newton) high-resolution Reflection Grating Spectrometer (RGS) spectrum to look for narrow spectral features from the nuclear environment of 1H0707-495. We do not find any evidence of a line-of-sight ionized wind (warm absorber). We do, however, detect broad emission lines, of width ∼5000 kms−1, consistent with Oviii Lyα, Nvii Lyα, Cvi Lyα and an Fexix/Fexx/Neix Heα blend. Intriguingly, these lines have both blueshifted and redshifted components, whose velocity shifts are consistent with an origin in an accretion disc at ∼1600 Rg from the black hole. The features can be interpreted as the narrow-line cores of the disc reflection spectrum, thus providing independent support for the discline interpretation of the X-ray spectrum of 1H0707-495. We discuss the relevance of our findings for the ‘X-ray broad-line region’ in other Seyferts, and for the origins of the optical broad-line region itself.
Institutional Challenges for National Groundwater Governance: Policies and Issues
Authors: Theesfeld Insa
Published: September 2009

Understanding the issues surrounding groundwater governance is a precondition for developing policy recommendations for both national and transboundary groundwater governance. This review discusses groundwater attributes relevant to the design of governance systems and provides a systematic review of current national groundwater governance differentiated by various policy instruments. The synthesis of both resource system characteristics and experience with policy instruments allows us to conceptualize institutional aspects of groundwater governance. This leads to six institutional aspects: (1) voluntary compliance; (2) tradition and mental models; (3) administrative responsibility and bureaucratic inertia; (4) conflict resolution mechanisms; (5) political economy; and (6) information deficits. Each of these issues embodies institutional challenges for national and international policy implementation.
Hypertension in the Postpartum Woman: Clinical Update for the Hypertension Specialist
Authors: Ghuman Nimrta , Rheiner Jacqueline , Tendler Beatriz E. , White William B.
Published: September 2009

Hypertension can persist from pregnancy or present de novo in the postpartum period and continue to pose a risk to maternal well‐being. These risks are magnified as many patients present after hospital discharge and go unrecognized because of decreased medical surveillance after delivery. Guidelines for the management of postpartum hypertension are lacking, often resulting in imprecise diagnoses and incorrect treatment strategies. As hypertension specialists are called upon to provide advice to obstetricians regarding the management of hypertension in the postpartum period, it becomes important for the hypertension specialist to develop expertise in the evaluation and treatment of hypertensive women during the postpartum period. The purpose of this clinical review article is to provide an approach to the management of postpartum hypertension.
Land use history and site location are more important for grassland species richness than local soil properties
Authors: Cousins Sara A. O. , Lindborg Regina , Mattsson Sofia
Published: September 2009

Lately there has been a shift in Sweden from grazing species‐rich semi‐natural grasslands towards grazing ex‐arable fields in the modern agricultural landscape. Grazing ex‐arable fields contain a fraction of the plant species richness confined to semi‐natural grasslands. Still, they have been suggested as potential target sites for re‐creation of semi‐natural grasslands. We asked to what extent does fine‐scale variation in soil conditions, management history and site location effect local plant diversity in grazed ex‐arable fields. We examined local soil conditions such as texture, pH, organic carbon, nitrogen (N) and extractable phosphate (P) and effects on plant richness in ten pairs of grazed ex‐fields and neighbouring semi‐natural grasslands in different rural landscapes. Each grassland pair where in the same paddock. A multivariate test showed that site location and land use history explained more of differences in species richness than local soil property variables. Plant species richness was positively associated to grazed ex‐fields with low pH, low N and P levels. Sites with high plant richness in semi‐natural grasslands also had more species in the adjacent grazed ex‐fields, compared to sites neighbouring less species‐rich semi‐natural grasslands. Although both soil properties and species richness were different in grazed ex‐fields compared to semi‐natural grassland, the site location within a landscape, and vicinity to species‐rich grasslands, can override effects of soil properties. In conclusion, if properly located, ex‐arable fields may be an important habitat to maintain plant diversity at larger spatio‐temporal scales and should considered as potential sites for grassland restoration.
Normative Appeals to the Natural
Authors: VÄYRYNEN PEKKA
Published: September 2009

Surprisingly, many ethical realists and anti‐realists, naturalists and not, all accept some version of the following normative appeal to the natural (NAN): evaluative and normative facts hold solely in virtue of natural facts, where their naturalness is part of what fits them for the job. This paper argues not that NAN is false but that NAN has no adequate non‐parochial justification (a justification that relies only on premises which can be accepted by more or less everyone who accepts NAN) to back up this consensus. I show that we cannot establish versions of NAN which are interesting in their own right (and not merely as instances of a general naturalistic ontology) by appealing to the nature of natural properties or the kind of in‐virtue‐of relation to which NAN refers, plus other plausible non‐parochial assumptions. On the way, I distinguish different types of ‘in virtue of’ claims. I conclude by arguing that the way in which assessment of meta‐ethical hypotheses is theory‐dependent predicts the failure of non‐parochial justifications of NAN.
Contextualism, Subject‐Sensitive Invariantism, and the Interaction of ‘Knowledge’‐Ascriptions with Modal and Temporal Operators*
Authors: BLOME‐TILLMANN MICHAEL
Published: September 2009

Jason Stanley has argued recently that Epistemic Contextualism (EC) and Subject‐Sensitive Invariantism (SSI) are explanatorily on a par with regard to certain data arising from modal and temporal embeddings of ‘knowledge’‐ascriptions. This paper argues against Stanley that EC has a clear advantage over SSI in the discussed field and introduces a new type of linguistic datum strongly suggesting the falsity of SSI.
Against Arguments from Reference*
Authors: MALLON RON , MACHERY EDOUARD , NICHOLS SHAUN , STICH STEPHEN
Published: September 2009

It is common in various quarters of philosophy to derive philosophically significant conclusions from theories of reference. In this paper, we argue that philosophers should give up on such ‘arguments from reference.’ Intuitions play a central role in establishing theories of reference, and recent cross‐cultural work suggests that intuitions about reference vary across cultures and between individuals within a culture (Machery et al. 2004). We argue that accommodating this variation within a theory of reference undermines arguments from reference.
Inconsistency Theories of Semantic Paradox
Authors: PATTERSON DOUGLAS
Published: September 2009

It is argued that a certain form of the view that the semantic paradoxes show that natural languages are “inconsistent” provides the best response to the semantic paradoxes. After extended discussions of the views of Kirk Ludwig and Matti Eklund, it is argued that in its strongest formulation the view maintains that understanding a natural language is sharing cognition of an inconsistent semantic theory for that language with other speakers. A number of aspects of this approach are discussed and a few objections are entertained.
Perception, Content and Rationality
Authors: PEACOCKE CHRISTOPHER
Published: September 2009

Anil Gupta’s Empiricism and Experience is a stylish and stimulating contribution to our subject. My expectation is that those who disagree with some of its central theses will, like me, learn greatly from thinking through where and why they part company with Gupta’s lucidly presented position. For the purposes of a Symposium, I select three points of disagreement. Each point in one way or another concerns the epistemic role of the content of experience.
The Policies and Politics of Industrial Upgrading in Thailand during the Thaksin Era (2001–2006)
Authors: Lauridsen Laurids S.
Published: September 2009

What happens when developing countries can no longer grow by simply exploiting their existing comparative advantages in natural resources or cheap labor? When entering the 21st century Thailand was confronted with that question, but in comparison with other East Asian countries it was also a laggard in relation to industrial technology development. Prime Minister Thaksin Shinawatra placed industrial upgrading high on the policy agenda. This article combines a policy cycle analysis with a political analysis. It examines the ability and willingness of the Thaksin government to design and implement an adequate and coherent set of industrial upgrading policies with a particular emphasis on implementation issues. It is argued that although many initiatives were taken during the Thaksin era, they did not add up to an adequate and coherent set of industrial upgrading policies. This was partly due to institutional legacies in the bureaucratic system but mainly a result of the logic of politics, including the nature of political coalition‐building.
International Actors Leading in Relief Efforts: 2004 Indian Ocean Tsunami Aid Assessment
Authors: Page Courtney M.
Published: September 2009

The Indian Ocean tsunami was one of the most devastating natural disasters the world has seen in the last 50 years. Following the calamities, the world responded and international actors went to work to relieve human suffering and rebuild the infrastructure that lay in ruins. This study examines the collective experiences of 21 organizations according to six disaster management dimensions: disaster preparedness, early recovery/livelihood support, public awareness, capacity‐building, accountability and measuring mechanisms, and coordination post‐disaster. The findings of this study provide policy recommendations according to the accomplishments, limitations, and progress made since 2004 shared by organizations responding to the largest and most publicized humanitarian crisis in recent times.
Marching toward a Harmonious Society: Happiness, Regime Satisfaction, and Government Performance in Contemporary Urban China
Authors: Lou Diqing
Published: September 2009

This study examined the happiness of citizens in urban China. Empirical measurements were made of the relationship of reported happiness to economic variables, as well as to citizens' satisfaction with government policies. Employing the 2002 Asian Barometer Survey and the Amelia statistical software package, I found that happiness is strongly correlated both to absolute economic conditions and to relative economic status. Furthermore, citizens who perceived government policies as being responsive to their needs were more likely to report a high level of personal well‐being. This empirical analysis confirms the direction of Chinese leader Hu Jintao's development strategy, which seeks to promote widespread economic prosperity among Chinese citizens. The study results indicate that a healthy and balanced economy is essential in improving urban happiness in China. Based on these results, I argue that the Chinese government can further improve citizen happiness by providing ample employment opportunities and promoting progressive housing policies.
The Impact of Government Corruption and Monopolized Industries on Poverty and Income Disparity in Urban China
Authors: Lollar Xia Li
Published: September 2009

This article examines the impact of government corruption and state monopolized industries on poverty and income disparity in urban China. Urban poverty and income disparity in China have increased sharply in recent years. The gap between the rich and poor has become so alarmingly wide that it has caused riots and violent protests in cities and towns across the country. While most studies on the roots of urban poverty and income disparity in China have focused on factors, such as unemployment, rural‐to‐urban migration, and lack of a social safety net, this study investigates the impact of government corruption and state‐monopolized industries on urban poor and income inequality. This study argues that the root causes of the fast‐growing gap between the rich and poor are the irrationally high income gained through the monopoly of state‐owned industries, the legal gains derived from graft, corruption, and power‐for‐money transactions.
Theoretical and Experimental Characterization for the Inelastic Behavior of the Micro-/Nanostructured Thin Films Using Strain Gradient Plasticity With Interface Energy
Authors: Voyiadjis George Z. , Deliktas Babur
Published: September 2009

Thin film technology is pervasive in many applications, including microelectronics, optics, magnetic, hard and corrosion resistant coatings, micromechanics, etc. Therefore, basic research activities will be necessary in the future to increase knowledge and understanding and to develop predictive capabilities for relating fundamental physical and chemical properties to the microstructure and performance of thin films in various applications. In basic research, special model systems are needed for quantitative investigation of the relevant and fundamental processes in thin film material science. Because of the diversity of the subject and the sheer volume of the publications, a complete a review of the area of the current study is focused particularly on the experimental and theoretical investigations for the inelastic behavior of the micro-/nanostructured thin films.
Multiscale Experiments: State of the Art and Remaining Challenges
Authors: Agrawal R. , Espinosa H. D.
Published: September 2009

In this article we review recent advances in experimental techniques for the mechanical characterization of materials and structures at various length scales with an emphasis in the submicron- and nanoregime. Advantages and disadvantages of various approaches are discussed to highlight the need for carefully designed experiments and rigorous analysis of experimentally obtained data to yield unambiguous findings. By examining in depth a few case studies we demonstrate that the development of robust and innovative experimentation is crucial for the advancement of theoretical frameworks, assessment of model predictive capabilities, and discovery of new physical phenomena.
Semi-Empirical Potential Methods for Atomistic Simulations of Metals and Their Construction Procedures
Authors: Kim Seong-Gon , Horstemeyer M. F. , Baskes M. I. , Rais-Rohani Masoud , Kim Sungho , Jelinek B. , Houze J. , Moitra Amitava , Liyanage Laalitha
Published: September 2009

General theory of semi-empirical potential methods including embedded-atom method and modified-embedded-atom method (MEAM) is reviewed. The procedures to construct these potentials are also reviewed. A multi-objective optimization (MOO) procedure has been developed to construct MEAM potentials with minimal manual fitting. This procedure has been applied successfully to develop a new MEAM potential for magnesium. The MOO procedure is designed to optimally reproduce multiple target values that consist of important material properties obtained from experiments and first-principle calculations based on density-functional theory. The optimized target quantities include elastic constants, cohesive energies, surface energies, vacancy-formation energies, and the forces on atoms in a variety of structures. The accuracy of the present potential is assessed by computing several material properties of Mg including their thermal properties. We found that the new MEAM potential shows a significant improvement over previously published potentials, especially for the atomic forces and melting temperature calculations.
Microstructure Design to Improve Wear Resistance in Bioimplant UHMWPE Materials
Authors: Li D. S. , Garmestani H. , Ahzi S. , Khaleel M. , Ruch D.
Published: September 2009

A microstructure design framework for multiscale modeling of wear resistance in bioimplant materials is presented here. The increase in service lifetime of arthroplasty depends on whether we can predict wear resistance and microstructure evolution of a bioimplant material made from ultra high molecular weight polyethylene during processing. Experimental results show that the anisotropy introduced during deformation increases wear resistance in desired directions. After uniaxial compression, wear resistance along the direction, perpendicular to compression direction, increased 3.3 times. Micromechanical models are used to predict microstructure evolution and the improvement in wear resistance during processing. Predicted results agree well with the experimental data. These models may guide the materials designer to optimize processing to achieve better wear behavior along desired directions.