bluuebunny/crossref_metadata_2025 huggingface dataset:
Team history and choking under pressure in major soccer penalty shootouts
Authors: Jordet Geir , Hartman Esther , Jelle Vuijk Pieter
Published: September 2011

This study examined the links between historical team results and individual players’ subsequent performances in a high‐pressure real‐world sport situation. Videos were obtained from all soccer penalty shootouts held in two major international tournaments (World Cup and European Championships) between 1976 and 2006 (n= 260 players/309 kicks), and we controlled for team ability and country. The results showed that players on teams with preceding losses performed worse and generally took their shots more quickly than players on teams with preceding wins. These differences were also found with players who took no personal part in the preceding games. In conclusion, the results support the existence of historical dependency effects for performance on important and dramatic high‐pressure tasks and they are in part consistent with a view of choking under pressure as a function of threatened egotism and self‐regulation failure.
Visualizing Uncertainty About the Future
Authors: Spiegelhalter David , Pearson Mike , Short Ian
Published: September 2011

We are all faced with uncertainty about the future, but we can get the measure of some uncertainties in terms of probabilities. Probabilities are notoriously difficult to communicate effectively to lay audiences, and in this review we examine current practice for communicating uncertainties visually, using examples drawn from sport, weather, climate, health, economics, and politics. Despite the burgeoning interest in infographics, there is limited experimental evidence on how different types of visualizations are processed and understood, although the effectiveness of some graphics clearly depends on the relative numeracy of an audience. Fortunately, it is increasingly easy to present data in the form of interactive visualizations and in multiple types of representation that can be adjusted to user needs and capabilities. Nonetheless, communicating deeper uncertainties resulting from incomplete or disputed knowledge—or from essential indeterminacy about the future—remains a challenge.
A Partial Pelvis of
Australopithecus sediba
Authors: Kibii Job M. , Churchill Steven E. , Schmid Peter , Carlson Kristian J. , Reed Nichelle D. , de Ruiter Darryl J. , Berger Lee R.
Published: September 2011

Although it had a small brain and skull,
Australopithecus sediba
shows some human-like features in its reconstructed pelvis.
Aeroelastic Flutter Produces Hummingbird Feather Songs
Authors: Clark Christopher J. , Elias Damian O. , Prum Richard O.
Published: September 2011

Hummingbirds produce diverse courtship sounds by using resonantly fluttering tail feathers.
An Expanded Palette of Genetically Encoded Ca
2+
Indicators
Authors: Zhao Yongxin , Araki Satoko , Wu Jiahui , Teramoto Takayuki , Chang Yu-Fen , Nakano Masahiro , Abdelfattah Ahmed S. , Fujiwara Manabi , Ishihara Takeshi , Nagai Takeharu , Campbell Robert E.
Published: September 2011

Directed protein evolution provides a series of fluorescent protein-based indicators for multicolor Ca2
+
imaging.
Synthesized Light Transients
Authors: Wirth A. , Hassan M. Th. , Grguraš I. , Gagnon J. , Moulet A. , Luu T. T. , Pabst S. , Santra R. , Alahmed Z. A. , Azzeer A. M. , Yakovlev V. S. , Pervak V. , Krausz F. , Goulielmakis E.
Published: September 2011

Light spanning the near infrared to the ultraviolet has been confined in pulses shorter than a single optical cycle.
Antarctic Ice Flow Revealed
Authors: Cuffey Kurt M.
Published: September 2011

Satellite radar imaging provides a comprehensive view of the shifting surface of the Antarctic Ice Sheet.
How Many Cell Types Does It Take to Wire a Brain?
Authors: Ransohoff Richard M. , Stevens Beth
Published: September 2011

Microglia play an important role in the maturation of synaptic circuits in newborn mice.
Getting to the Heart of Mechanotransduction
Authors: Hidalgo Cecilia , Donoso Paulina
Published: September 2011

Stretching a heart muscle cell triggers signaling by reactive oxygen species to produce Ca
2+
sparks.
Which Way to the Island?
Authors: Clery Daniel
Published: September 2011

As teams vie to create the next new addition to the periodic table, the best path forward for superheavy-element research remains unclear.
Outer Membrane Vesicles Induce Immune Responses to Virulence Proteins and Protect against Colonization by Enterotoxigenic Escherichia coli
Authors: Roy Koushik , Hamilton David J. , Munson George P. , Fleckenstein James M.
Published: September 2011

Enterotoxigenic
Escherichia coli
(ETEC) strains are a heterogeneous group of pathogens that produce heat-labile (LT) and/or heat-stable (ST) enterotoxins. Collectively, these pathogens are responsible for hundreds of thousands of deaths annually in developing countries, particularly in children under the age of 5 years. The heterogeneity of previously investigated molecular targets and the lack of complete sustained protection afforded by antitoxin immunity have impeded progress to date toward a broadly protective vaccine. Many pathogens, including ETEC, have the capacity to form outer membrane vesicles (OMV), which often contain one or more virulence proteins. Prompted by recent studies that identified several immunogenic virulence proteins in outer membrane vesicles of ETEC, we sought to examine the immunogenicity and protective efficacy of these structures in a murine model of infection. Here we demonstrate that immunization with OMV impairs ETEC colonization of the small intestine and stimulates antibodies that recognize the heat-labile toxin and two additional putative virulence proteins, the EtpA adhesin and CexE. Similar to earlier studies with EtpA, vaccination with LT alone also inhibited intestinal colonization. Together, these findings suggest that OMV could be exploited to deliver protective antigens relevant to development of ETEC vaccines.
Assessment of Lactobacillus gasseri as a Candidate Oral Vaccine Vector
Authors: Stoeker Laura , Nordone Shila , Gunderson Sara , Zhang Lin , Kajikawa Akinobu , LaVoy Alora , Miller Michael , Klaenhammer Todd R. , Dean Gregg A.
Published: September 2011

Lactobacillusspecies are commensal bacteria that have long been recognized as probiotic microbes and are generally regarded as safe (GRAS) for human consumption. We have investigated the use ofL. gasserias a vaccine vector for oral immunization against mucosal pathogens. Recent research has shown that the immune response to different lactobacilli can vary widely depending on the species or subspecies ofLactobacillusbeing studied. While some lactobacilli seem to induce oral tolerance, others induce an adaptive immune response. This study characterized the systemic and mucosal immune response to wild-type and genetically modifiedL. gasseri. L. gasseriprimarily activates TLR2/6, with additional activation through the TLR2 homodimer. To expand the Toll-like receptor (TLR) activation profile ofL. gasseriand the immunogenicity of the vector, a plasmid containingfliC, the gene encoding bacterial flagellin, was introduced which resulted in the strong activation of TLR5. The treatment of human myeloid dendritic cells with recombinant lactobacilli expressing flagellin triggered phenotypic maturation and the release of proinflammatory cytokines. In contrast, bacterial treatment also resulted in a statistically significant increase in IL-10 production.In vivostudies established that treatment withL. gasseriled to a diversification of B-cell populations in the lamina propria of the murine colon. Furthermore, treatment with genetically modifiedL. gasseriled to a significant decrease in the percentage of FoxP3+colonic lymphocytes. Taken together, these data clarify the interaction ofL. gasseriwith the host immune system and support further investigation of thein vivoimmunogenicity ofL. gasseriexpressing both flagellin and candidate vaccine antigens.
Development of an Automated and Multiplexed Serotyping Assay for Streptococcus pneumoniae
Authors: Yu Jigui , Lin Jisheng , Kim Kyung-Hyo , Benjamin William H. , Nahm Moon H.
Published: September 2011

Streptococcus pneumoniae
expresses more than 90 capsule types, and currently available pneumococcal vaccines are designed to provide serotype-specific protection. Consequently, serotyping of pneumococcal isolates is important for determining the serotypes to be included in pneumococcal vaccines and to monitor their efficacy. Yet serotyping of pneumococcal isolates has remained a significant technical challenge. By multiplexing many assays, we have now developed a simple yet comprehensive serotyping assay system that can not only identify all known pneumococcal serotypes but also subdivide nontypeable (NT) isolates into those with or without the conventional capsule locus. We have developed this assay system to require only six key reagents: two are used in one multiplex inhibition-type immunoassay, and four are required in two multiplex PCR-based assays. The assay system is largely automated by a seamless combination of monoclonal antibody-based and PCR-based multiplex assays using the flow cytometric bead array technology from Luminex. The assay system has been validated with a panel of pneumococci expressing all known pneumococcal serotypes and was found to be easily transferable to another laboratory.
Molecular Detection of Resistance Determinants
Authors: Ledeboer Nathan A. , Hodinka Richard L.
Published: September 2011

The development of new antibiotics and the emergence of novel resistance mechanisms to counteract these drugs create a dynamic and challenging task for the clinical microbiology laboratory. The goal of antimicrobial resistance testing is to provide timely therapeutic options to guide the management of infectious diseases resulting from bacterial infections. Antimicrobial susceptibility has classically been determined using a variety of
in vitro
methods, such as disk diffusion, broth microdilution, and automated instrument-based methods. Using these methods, the reporting of MICs and interpretations can require 24 to 96 h after a pure culture of the suspected pathogen is obtained (6). Unfortunately, results obtained after 48 h are often of little clinical value and are unlikely to alter antimicrobial therapy. The extended turnaround associated with phenotypic antimicrobial resistance testing provides an opportunity for the use of alternative technologies capable of producing more timely results. The first reports in this supplement explore the manner in which the criteria for interpreting MICs are developed and the clinical relevance of antimicrobial susceptibility testing. In this report, we present an alternative to routine susceptibility testing and examine the role of molecular susceptibility testing now and in the future.
Triazole and Echinocandin MIC Distributions with Epidemiological Cutoff Values for Differentiation of Wild-Type Strains from Non-Wild-Type Strains of Six Uncommon Species of
Candida
Authors: Pfaller Michael A. , Castanheira Mariana , Diekema Daniel J. , Messer Shawn A. , Jones Ronald N.
Published: September 2011

When clinical susceptibility breakpoints (CBPs) are absent, establishing wild-type (WT) MIC distributions and epidemiological cutoff values (ECVs) provides a sensitive means for detecting emerging resistance. We determined species-specific ECVs for anidulafungin (ANF), caspofungin (CSF), micafungin (MCF), fluconazole (FLC), posaconazole (PSC), and voriconazole (VRC) for six rarer
Candida
species (819 strains) using isolates obtained from the ARTEMIS Program and the SENTRY Antimicrobial Surveillance Program, all tested by a reference broth microdilution method. The calculated ECVs, expressed in μg/ml (and the percentages of isolates that had MICs less than or equal to the ECVs), for ANF, CSF, MCF, FLC, PSC, and VRC, respectively, were 0.12 (95.2), 0.12 (97.8), 0.12 (100.0), 0.5 (95.7), 0.12 (98.6), and 0.03 (100.0) for
Candida dubliniensis
; 4 (100.0), 2 (96.0), 2 (99.1), 8 (95.0), 0.5 (97.5), and 0.25 (98.0) for
C. guilliermondii
; 0.25 (98.9), 0.03 (98.0), 0.12 (97.5), 1 (99.1), 0.25 (99.1), and 0.015 (100.0) for
C. kefyr
; 2 (100.0), 1 (99.6), 0.5 (96.6), 2 (96.1), 0.25 (98.6), and 0.03 (96.6) for
C. lusitaniae
; and 2 (100.0), 0.5 (100.0), 1 (100.0), 2 (98.0), 0.25 (97.1), and 0.06 (98.0) for
C. orthopsilosis
, but for
C. pelliculosa
, ECVs could be determined only for CSF (0.12 [94.4]), FLC (4 [98.2]), PSC (2 [98.2]), and VRC (0.25 [98.2]). In the absence of species-specific CBP values, these WT MIC distributions and ECVs will be useful for monitoring the emergence of reduced susceptibility to the triazole and echinocandin antifungals.
HIV-1 Coinfection and Morphine Coexposure Severely Dysregulate Hepatitis C Virus-Induced Hepatic Proinflammatory Cytokine Release and Free Radical Production: Increased Pathogenesis Coincides with Uncoordinated Host Defenses
Authors: El-Hage Nazira , Dever Seth M. , Fitting Sylvia , Ahmed Tasrif , Hauser Kurt F.
Published: September 2011

Coinfection with human immunodeficiency virus type-1 (HIV-1) and hepatitis C virus (HCV) is a global problem that is more prevalent in injection drug users because they have a higher risk for acquiring both viruses. The roles of inflammatory cytokines and oxidative stress were examined in HIV-1- and HCV-coinfected human hepatic cells. Morphine (the bioactive product of heroin), HIV-1 Tat and the MN strain gp120 (gp120MN) proteins, and X4 HIV-1LAI/IIIBand R5 HIV-1SF162isolates were used to study the mechanisms of disease progression in HCV (JFH1)-infected Huh7.5.1 cell populations. HCV increased tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) release and augmented production of reactive oxygen species (ROS), nitric oxide (NO), and 3-nitrotyrosine (3-NT) in Huh7.5.1 cells. Morphine preferentially affected R5-tropic, but not X4-tropic, HIV-1 interactions with Huh7.5.1 cells. HIV-1 proteins or isolates increased cytokine release in HCV-infected cells, while adding morphine to coinfected cells caused complex imbalances, significantly disrupting cytokine secretion depending on the cytokine, morphine concentration, exposure duration, and particular pathogen involved. Production of ROS, NO, and 3-NT increased significantly in HCV- and HIV-1-coexposed cells while exposure to morphine further increased ROS. The proteasome inhibitor MG132 significantly decreased oxyradicals, cytokine levels, and HCV protein levels. Our findings indicate that hepatic inflammation is increased by combined exposure to HCV and HIV-1, that the ubiquitin-proteasome system and NF-κB contribute to key aspects of the response, and that morphine further exacerbates the disruption of host defenses. The results suggest that opioid abuse and HIV-1 coinfection each further accelerate HCV-mediated liver disease by dysregulating immune defenses.
Replication of the Rotavirus Genome Requires an Active Ubiquitin-Proteasome System
Authors: López Tomás , Silva-Ayala Daniela , López Susana , Arias Carlos F.
Published: September 2011

Here we show that the ubiquitin-proteasome system is required for the efficient replication of rotavirus RRV in MA104 cells. The proteasome inhibitor MG132 decreased the yield of infectious virus under conditions where it severely reduces the synthesis of not only viral but also cellular proteins. Addition of nonessential amino acids to the cell medium restored both viral protein synthesis and cellular protein synthesis, but the production of progeny viruses was still inhibited. In medium supplemented with nonessential amino acids, we showed that MG132 does not affect rotavirus entry but inhibits the replication of the viral genome. It was also shown that it prevents the efficient incorporation into viroplasms of viral polymerase VP1 and the capsid proteins VP2 and VP6, which could explain the inhibitory effect of MG132 on genome replication and infectious virus yield. We also showed that ubiquitination is relevant for rotavirus replication since the yield of rotavirus progeny in cells carrying a temperature-sensitive mutation in the E1 ubiquitin-activating enzyme was reduced at the restrictive temperature. In addition, overexpression of ubiquitin in MG132-treated MA104 cells partially reversed the effect of the inhibitor on virus yield. Altogether, these data suggest that the ubiquitin-proteasome (UP) system has a very complex interaction with the rotavirus life cycle, with both the ubiquitination and proteolytic activities of the system being relevant for virus replication.
Structural Studies of Adeno-Associated Virus Serotype 8 Capsid Transitions Associated with Endosomal Trafficking
Authors: Nam Hyun-Joo , Gurda Brittney L. , McKenna Robert , Potter Mark , Byrne Barry , Salganik Maxim , Muzyczka Nicholas , Agbandje-McKenna Mavis
Published: September 2011

The single-stranded DNA (ssDNA) parvoviruses enter host cells through receptor-mediated endocytosis, and infection depends on processing in the early to late endosome as well as in the lysosome prior to nuclear entry for replication. However, the mechanisms of capsid endosomal processing, including the effects of low pH, are poorly understood. To gain insight into the structural transitions required for this essential step in infection, the crystal structures of empty and green fluorescent protein (GFP) gene-packaged adeno-associated virus serotype 8 (AAV8) have been determined at pH values of 6.0, 5.5, and 4.0 and then at pH 7.5 after incubation at pH 4.0, mimicking the conditions encountered during endocytic trafficking. While the capsid viral protein (VP) topologies of all the structures were similar, significant amino acid side chain conformational rearrangements were observed on (i) the interior surface of the capsid under the icosahedral 3-fold axis near ordered nucleic acid density that was lost concomitant with the conformational change as pH was reduced and (ii) the exterior capsid surface close to the icosahedral 2-fold depression. The 3-fold change is consistent with DNA release from an ordering interaction on the inside surface of the capsid at low pH values and suggests transitions that likely trigger the capsid for genome uncoating. The surface change results in disruption of VP-VP interface interactions and a decrease in buried surface area between VP monomers. This disruption points to capsid destabilization which may (i) release VP1 amino acids for its phospholipase A2 function for endosomal escape and nuclear localization signals for nuclear targeting and (ii) trigger genome uncoating.
Understanding ethnic and other socio-demographic differences in patient experience of primary care: evidence from the English General Practice Patient Survey
Authors: Lyratzopoulos G , Elliott M , Barbiere J M , Henderson A , Staetsky L , Paddison C , Campbell J , Roland M
Published: September 2011

Background

Ethnic minorities and some other patient groups consistently report lower scores on patient surveys, but the reasons for this are unclear. This study examined whether low scores of ethnic minority and other socio-demographic groups reflect their concentration in poorly performing primary care practices, and whether any remaining differences are consistent across practices.

Methods

Using data from the 2009 English General Practice Patient Survey (2 163 456 respondents from 8267 general practices) this study examined associations between patient socio-demographic characteristics and 11 measures of patient-reported experience.

Findings

South Asian and Chinese patients, younger patients, and those in poor health reported a less positive primary care experience than White patients, older patients and those in better health. For doctor communication, about half of the overall difference associated with South Asian patients (ranging from −6 to −9 percentage points) could be explained by their concentration in practices with low scores, but the other half arose because they reported less positive experiences than White patients in the same practices. Practices varied considerably in the direction and extent of ethnic differences. In some practices ethnic minority patients reported better experience than White patients. Differences associated with gender, Black ethnicity and deprivation were small and inconsistent.

Conclusion

Substantial ethnic differences in patient experience exist in a national healthcare system providing universal coverage. Improving the experience of patients in low-scoring practices would not only improve the quality of care provided to their White patients but it would also substantially reduce ethnic group differences in patient experience. There were large variations in the experiences reported by ethnic minority patients in different practices: practices with high patient experience scores from ethnic minority patients could be studied as models for quality improvement.
To resuscitate or not to resuscitate: a logistic regression analysis of physician-related variables influencing the decision
Authors: Einav Sharon , Alon Gady , Kaufman Nechama , Braunstein Rony , Carmel Sara , Varon Joseph , Hersch Moshe
Published: September 2011

Objective

To determine whether variables in physicians' backgrounds influenced their decision to forego resuscitating a patient they did not previously know.

Methods

Questionnaire survey of a convenience sample of 204 physicians working in the departments of internal medicine, anaesthesiology and cardiology in 11 hospitals in Israel.

Results

Twenty per cent of the participants had elected to forego resuscitating a patient they did not previously know without additional consultation. Physicians who had more frequently elected to forego resuscitation had practised medicine for more than 5 years (p=0.013), estimated the number of resuscitations they had performed as being higher (p=0.009), and perceived their experience in resuscitation as sufficient (p=0.001). The variable that predicted the outcome of always performing resuscitation in the logistic regression model was less than 5 years of experience in medicine (OR 0.227, 95% CI 0.065 to 0.793; p=0.02).

Conclusion

Physicians' level of experience may affect the probability of a patient's receiving resuscitation, whereas the physicians' personal beliefs and values did not seem to affect this outcome.
Neurological oxygen toxicity
Authors: Farmery Scott , Sykes Oliver
Published: September 2011

SCUBA diving has several risks associated with it from breathing air under pressure—nitrogen narcosis, barotrauma and decompression sickness (the bends). Trimix SCUBA diving involves regulating mixtures of nitrogen, oxygen and helium in an attempt to overcome the risks of narcosis and decompression sickness during deep dives, but introduces other potential hazards such as hypoxia and oxygen toxicity convulsions. This study reports on a seizure during the ascent phase, its potential causes and management and discusses the hazards posed to the diver and his rescuer by an emergency ascent to the surface.
Evaluation of a completely automated tissue-sectioning machine for paraffin blocks
Authors: Onozato Maristela L , Hammond Stephen , Merren Mark , Yagi Yukako
Published: September 2011

Tissue-sectioning automation can be a resourceful tool in processing anatomical pathology specimens. The advantages of an automated system compared with traditional manual sectioning are the invariable thickness, uniform orientation and fewer tissue-sectioning artefacts. This short report presents the design of an automated tissue-sectioning device and compares the sectioned specimens with normal manual tissue sectioning performed by an experienced histology technician. The automated system was easy to use, safe and the sectioned material showed acceptable quality with well-preserved morphology and tissue antigenicity. It is expected that the turnaround time will be improved in the near future.
Potential climate change impacts on thermal habitats of Pacific salmon (Oncorhynchus spp.) in the North Pacific Ocean and adjacent seas
Authors: Abdul-Aziz Omar I. , Mantua Nathan J. , Myers Katherine W.
Published: September 2011

We developed spatially explicit representations for seasonal high-seas (open ocean) thermal habitats for six species of Pacific salmon ( Oncorhynchus  spp.) and evaluated the effects of natural climate variability and projected changes under three Intergovernmental Panel on Climate Change scenarios of future greenhouse gas emissions. Changes in high-seas habitat due to natural climatic variation in 20th century were small relative to that under anthropogenic climate change scenarios for the middle to late 21st century. Under a multimodel ensemble average of global climate model outputs using A1B (medium) emissions scenario for the entire study area (North Pacific and part of Arctic Ocean), projected winter habitats of sockeye ( Oncorhynchus nerka ) decreased by 38%, and summer habitat decreased by 86% for Chinook ( Oncorhynchus tshawytscha ), 45% for sockeye, 36% for steelhead ( Oncorhynchus mykiss ), 30% for coho ( Oncorhynchus kisutch ), 30% for pink ( Oncorhynchus gorbuscha ), and 29% for chum ( Oncorhynchus keta ) salmon by 2100. Reductions were 25% lower for B1 (lower) emissions and 7% higher for A2 (higher) emissions scenarios. Projected habitat losses were largest in the Gulf of Alaska and western and central subarctic North Pacific. Nearly complete losses of Gulf of Alaska habitat for sockeye in both seasons and Chinook in summer raise important policy issues for North American fishery managers and governments.
Bayesian fishable biomass dynamics models incorporating fished area and relative fish density
Authors: Zhou Shijie , Punt Andre E. , Deng Roy , Kienzle Marco , Rochester Wayne
Published: September 2011

Fisheries typically experience large changes over time in fishing effort. The size of the area fished may also change substantially over time, mimicking the trend in fishing effort, and may have major effects on the population dynamics and fishing process. We extend a biomass dynamics model to incorporate fished area and relative fish density in fished and unfished areas. The fishable population is defined as those individuals in the fished area and those that are sufficiently close to the fished area that they could potentially move into fished area during the fishing season. We estimate fishable biomass using three models assuming different level of population mixing between fished and unfished areas (i.e., partial mixing, full mixing, and no mixing). The models are implemented within a hierarchical Bayesian framework. Model performance is explored using simulations, and the approach is illustrated using logbook data for two tiger prawn species in Australia’s Northern Prawn Fishery. The partial mixing model that involves estimating a mixing parameter performs better than the models that assume no or full mixing. The methods could be applied to other fisheries where the area fished has changed substantially over the history of the fishery.
Accounting for fish shoals in single- and multi-species survey data using mixture distribution models
Authors: Thorson James T. , Stewart Ian J. , Punt André E.
Published: September 2011

A scientific bottom trawl survey targeting Pacific rockfishes (Sebastes spp.) occasionally yields extraordinary catch events (ECEs) in which catch-per-unit-area is much greater than usual. We hypothesize that ECEs result from trawl catches of fish shoals. We developed mixture distribution models for positive catch rates to identify spatial covariates associated with ECEs or normal trawl catches and used simulation modeling to contrast the performance of mixture distribution and conventional log-linear models for estimating an annual index of positive catch rates. Finally, mixed-effects modeling was applied to multispecies data to evaluate the hypothesis that ECEs are related to shoaling behaviors. Results show that mixture distribution models are often selected over conventional models for shoaling species and that untrawlable habitat has a positive effect on rockfish densities. Simulation shows that mixture distribution models can perform as well as or better than conventional models at predicting positive catch rates. Finally, model selection supports the hypothesis that shoaling behaviors contribute to the occurrence of ECEs. We propose that greater understanding of ECEs and shoaling habitat selection could be useful in future spatial management and survey design and that mixture distribution models could improve methods for estimating annual indices of abundance.
THE NATURE OF Λ AND THE MASS OF THE GRAVITON: A CRITICAL VIEW
Authors: GAZEAU J.-P. , NOVELLO M.
Published: September 2011

The observational evidence of a cosmological constant Λ raises natural questions. Is Λ a universal constant fixing the geometry of an empty universe, as fundamental as the Planck constant or the speed of light in the vacuum? Its natural place is then on the left-hand side of the Einstein equation. Is it instead something emerging from a perturbation calculation performed on the metric gμν solution of the Einstein equation and to which it might be given a material status of (dark or bright) "energy"? It should then be part of the content of the right-hand side of the Einstein equations. The purpose of this paper is to analyze some of the arguments in favor of each one of these interpretations of the cosmological constant. Recent estimates based on observational data give a bound on the graviton mass to be about 100 Mpc-1. If this value and the current estimate on the cosmological constant Λ are put into perspective, one faces the interesting coincidence that between the Compton wavelength of the graviton and the cosmological constant there exists the relation [Formula: see text]. Since a physical quantity like mass originates in a minkowskian conservation law, we proceed with a group theoretical interpretation of this relation in terms of the two possible Λ-deformations of the Poincaré group, namely the de Sitter and anti de Sitter groups. We use a very suitable formula, the so-called Garidi mass, and the typically dS/AdS dimensionless parameter ħH/mc2 in order to make clear the asymptotic relations between minkowskian masses m and their possible dS/AdS counterparts. We conclude that if the fundamental state of the geometry of space-time is minkowskian, then the square of the mass of the graviton is proportional to Λ; otherwise, if the fundamental state is de Sitter, then the graviton is massless in the deSitterian sense.
SOME REMARKS ON f(R) THEORIES OF GRAVITY
Authors: JORÁS SERGIO E.
Published: September 2011

In this paper, I make a brief review of f(R) theories and their shortcomings — with some emphasis on the latter. I constrain myself to f(R) theories, the current acceleration of the (homegeneous) universe and the metric formalism (except at the very end).
OBSERVATION OF THE THERMAL CASIMIR FORCE IS OPEN TO QUESTION
Authors: KLIMCHITSKAYA G. L. , BORDAG M. , FISCHBACH E. , KRAUSE D. E. , MOSTEPANENKO V. M.
Published: September 2011

We discuss theoretical predictions for the thermal Casimir force and compare them with available experimental data. Special attention is paid to the recent claim of the observation of that effect, as predicted by the Drude model approach. We show that this claim is in contradiction with a number of experiments reported so far. We suggest that the experimental errors, as reported in support of the observation of the thermal Casimir force, are significantly underestimated. Furthermore, the experimental data at separations above 3μm are shown to be in agreement not with the Drude model approach, as is claimed, but with the plasma model. The seeming agreement of the data with the Drude model at separations below 3 μm is explained by the use of an inadequate formulation of the proximity force approximation.
WHAT IS CREDIBLE AND WHAT IS INCREDIBLE IN THE MEASUREMENTS OF THE CASIMIR FORCE
Authors: KLIMCHITSKAYA G. L. , MOSTEPANENKO V. M.
Published: September 2011

We comment on progress in measurements of the Casimir force and discuss what is the actual reliability of different experiments. In this connection a more rigorous approach to the usage of such concepts as accuracy, precision, and measure of agreement between experiment and theory, is presented. We demonstrate that all measurements of the Casimir force employing spherical lenses with centimeter-size curvature radii are fundamentally flawed due to the presence of bubbles and pits on their surfaces. The commonly used formulation of the proximity force approximation is shown to be inapplicable for centimeter-size lenses. New expressions for the Casimir force are derived taking into account surface imperfections. Uncontrollable deviations of the Casimir force from the values predicted using the assumption of perfect sphericity vary by a few tens of percent within the separation region from 1 to 3μm. This makes impractical further use of centimeter-size lenses in experiments on measuring the Casimir force.
ADAPTIVE DATA ANALYSIS VIA SPARSE TIME-FREQUENCY REPRESENTATION
Authors: HOU THOMAS Y. , SHI ZUOQIANG
Published: September 2011

We introduce a new adaptive method for analyzing nonlinear and nonstationary data. This method is inspired by the empirical mode decomposition (EMD) method and the recently developed compressed sensing theory. The main idea is to look for the sparsest representation of multiscale data within the largest possible dictionary consisting of intrinsic mode functions of the form {a(t) cos (θ(t))}, where a ≥ 0 is assumed to be smoother than cos (θ(t)) and θ is a piecewise smooth increasing function. We formulate this problem as a nonlinear L1 optimization problem. Further, we propose an iterative algorithm to solve this nonlinear optimization problem recursively. We also introduce an adaptive filter method to decompose data with noise. Numerical examples are given to demonstrate the robustness of our method and comparison is made with the EMD method. One advantage of performing such a decomposition is to preserve some intrinsic physical property of the signal, such as trend and instantaneous frequency. Our method shares many important properties of the original EMD method. Because our method is based on a solid mathematical formulation, its performance does not depend on numerical parameters such as the number of shifting or stop criterion, which seem to have a major effect on the original EMD method. Our method is also less sensitive to noise perturbation and the end effect compared with the original EMD method.
ON HILBERT SPECTRAL REPRESENTATION: A TRUE TIME-FREQUENCY REPRESENTATION FOR NONLINEAR AND NONSTATIONARY DATA
Authors: HUANG NORDEN E. , CHEN XIANYAO , LO MEN-TZUNG , WU ZHAOHUA
Published: September 2011

As the original definition on Hilbert spectrum was given in terms of total energy and amplitude, there is a mismatch between the Hilbert spectrum and the traditional Fourier spectrum, which is defined in terms of energy density. Rigorous definitions of Hilbert energy and amplitude spectra are given in terms of energy and amplitude density in the time-frequency space. Unlike Fourier spectral analysis, where the resolution is fixed once the data length and sampling rate is given, the time-frequency resolution could be arbitrarily assigned in Hilbert spectral analysis (HSA). Furthermore, HSA could also provide zooming ability for detailed examination of the data in a specific frequency range with all the resolution power. These complications have made the conversion between Hilbert and Fourier spectral results difficult and the conversion formula is elusive until now. We have derived a simple relationship between them in this paper. The conversion factor turns out to be simply the sampling rate for the full resolution cases. In case of zooming, there is another additional multiplicative factor. The conversion factors have been tested in various cases including white noise, delta function, and signals from natural phenomena. With the introduction of this conversion, we can compare HSA and Fourier spectral analysis results quantitatively.
SOME CONSIDERATIONS ON PHYSICAL ANALYSIS OF DATA
Authors: WU ZHAOHUA , HUANG NORDEN E. , CHEN XIANYAO
Published: September 2011

In this paper, we present some general considerations about data analysis from the perspective of a physical scientist and advocate the physical, instead of mathematical, analysis of data. These considerations have been accompanying our development of novel adaptive, local analysis methods, especially the empirical mode decomposition and its major variation, the ensemble empirical mode decomposition, and its preliminary mathematical explanations. A particular emphasis will be on the advantages and disadvantages of mathematical and physical constraints associated with various analysis methods. We argue that, using data analysis in a given temporal domain of observation as an example, the mathematical constraints imposed on data may lead to difficulties in understanding the physics behind the data. With such difficulties in mind, we promote adaptive, local analysis method, which satisfies fundamental physical principle of consequent evolution of a system being not able to change the past evolution of the system. We also argue, using the ensemble empirical mode decomposition as an example, that noise can be helpful to extract physically meaningful signals hidden in noisy data.
Vascular smooth muscle insulin resistance, but not hypertrophic signaling, is independent of angiotensin II-induced IRS-1 phosphorylation by JNK
Authors: Hitomi Hirofumi , Mehta Puja K. , Taniyama Yoshihiro , Lassègue Bernard , Seidel-Rogol Bonnie , San Martin Alejandra , Griendling Kathy K.
Published: September 2011

Angiotensin II (ANG II) has been implicated in the pathogenesis of diabetic micro- and macrovascular disease. In vascular smooth muscle cells (VSMCs), ANG II phosphorylates and degrades insulin receptor substrate-1 (IRS-1). While the pathway responsible for IRS-1 degradation in this system is unknown, c-Jun NH2-terminal kinase (JNK) has been linked with serine phosphorylation of IRS-1 and insulin resistance. We investigated the role of JNK in ANG II-induced IRS-1 phosphorylation, degradation, Akt activation, glucose uptake, and hypertrophic signaling, focusing on three IRS-1 phosphorylation sites: Ser302, Ser307, and Ser632. Maximal IRS-1 phosphorylation on Ser632 occurred at 5 min, on Ser307 at 30 min, and on Ser302 at 60 min. The JNK inhibitor SP600125 reduced ANG II-induced IRS-1 Ser307 phosphorylation (by 80%), IRS-1 Ser302 phosphorylation (by 70%), and IRS-1 Ser632 phosphorylation (by 50%). However, JNK inhibition had no effect on ANG II-mediated IRS-1 degradation, nor did it reverse the ANG II-induced decrease in Akt phosphorylation or glucose uptake. Transfection of VSMCs with mutants S307A, S302A, or S632A of IRS-1 did not block ANG II-mediated IRS-1 degradation. In contrast, JNK inhibition attenuated insulin-induced upregulation of collagen and smooth muscle α-actin in ANG II-pretreated cells. We conclude that phosphorylation of Ser307, Ser302, and Ser632 of IRS-1 is not involved in ANG II-mediated IRS-1 degradation, and that JNK alone does not mediate ANG II-stimulated IRS-1 degradation, but rather is responsible for the hypertrophic effects of insulin on smooth muscle.
Ammonia reduction with ornithine phenylacetate restores brain eNOS activity via the DDAH-ADMA pathway in bile duct-ligated cirrhotic rats
Authors: Balasubramaniyan Vairappan , Wright Gavin , Sharma Vikram , Davies Nathan A. , Sharifi Yalda , Habtesion Abeba , Mookerjee Rajeshwar P. , Jalan Rajiv
Published: September 2011

Ammonia is central in the pathogenesis of hepatic encephalopathy, which is associated with dysfunction of the nitric oxide (NO) signaling pathway. Ornithine phenylacetate (OP) reduces hyperammonemia and brain water in cirrhotic animals. This study aimed to determine whether endothelial NO synthase activity is altered in the brain of cirrhotic animals, whether this is associated with changes in the endogenous inhibitor, asymmetric-dimethylarginine (ADMA) and its regulating enzyme, dimethylarginine-dimethylaminohydrolase (DDAH-1), and whether these abnormalities are restored by ammonia reduction using OP. Sprague-Dawley rats were studied 4-wk after bile duct ligation (BDL) ( n = 16) or sham operation ( n = 8) and treated with placebo or OP (0.6 g/kg). Arterial ammonia, brain water, TNF-α, plasma, and brain ADMA were measured using standard techniques. NOS activity was measured radiometrically, and protein expression for NOS enzymes, ADMA, DDAH-1, 4-hydroxynonenol (4HNE), and NADPH oxidase (NOX)-1 were measured by Western blotting. BDL significantly increased arterial ammonia ( P < 0.0001), brain water ( P < 0.05), and brain TNF-α ( P < 0.01). These were reduced significantly by OP treatment. The estimated eNOS component of constitutive NOS activity was significantly lower ( P < 0.05) in BDL rat, and this was significantly attenuated in OP-treated animals. Brain ADMA levels were significantly higher and brain DDAH-1 significantly lower in BDL compared with sham ( P < 0.01) and restored toward normal following treatment with OP. Brain4HNE and NOX-1 protein expression were significantly increased in BDL rat brain, which were significantly decreased following OP administration. We show a marked abnormality of NO regulation in cirrhotic rat brains, which can be restored by reduction in ammonia concentration using OP.
Blood pressure and renal hemodynamic responses to acute angiotensin II infusion are enhanced in a female mouse model of systemic lupus erythematosus
Authors: Venegas-Pont Marcia , Mathis Keisa W. , Iliescu Radu , Ray William H. , Glover Porter H. , Ryan Michael J.
Published: September 2011

Inflammation and immune system dysfunction contributes to the development of cardiovascular and renal disease. Systemic lupus erythematosus (SLE) is a chronic autoimmune inflammatory disorder that carries a high risk for both renal and cardiovascular disease. While hemodynamic changes that may contribute to increased cardiovascular risk have been reported in humans and animal models of SLE, renal hemodynamics have not been widely studied. The renin-angiotensin system (RAS) plays a central role in renal hemodynamic control, and although RAS blockade is a common therapeutic strategy, the role of RAS in hemodynamic function during SLE is not clear. This study tested whether mean arterial pressure (MAP) and renal hemodynamic responses to acute infusions of ANG II in anesthetized animals were enhanced in an established female mouse model of SLE (NZBWF1). Baseline MAP was not different between anesthetized SLE and control (NZWLacJ) mice, while renal blood flow (RBF) was significantly lower in mice with SLE. SLE mice exhibited an enhanced pressor response and greater reduction in RBF after ANG II infusion. An acute infusion of the ANG II receptor blocker losartan increased RBF in control mice but not in mice with SLE. Renin and ANG II type 1 receptor expression was significantly lower, and ANG II type 2 receptor expression was increased in the renal cortex from SLE mice compared with controls. These data suggest that there are fewer ANG II receptors in the kidneys from mice with SLE but that the existing receptors exhibit an enhanced sensitivity to ANG II.
Central circuitries for body temperature regulation and fever
Authors: Nakamura Kazuhiro
Published: September 2011

Body temperature regulation is a fundamental homeostatic function that is governed by the central nervous system in homeothermic animals, including humans. The central thermoregulatory system also functions for host defense from invading pathogens by elevating body core temperature, a response known as fever. Thermoregulation and fever involve a variety of involuntary effector responses, and this review summarizes the current understandings of the central circuitry mechanisms that underlie nonshivering thermogenesis in brown adipose tissue, shivering thermogenesis in skeletal muscles, thermoregulatory cardiac regulation, heat-loss regulation through cutaneous vasomotion, and ACTH release. To defend thermal homeostasis from environmental thermal challenges, feedforward thermosensory information on environmental temperature sensed by skin thermoreceptors ascends through the spinal cord and lateral parabrachial nucleus to the preoptic area (POA). The POA also receives feedback signals from local thermosensitive neurons, as well as pyrogenic signals of prostaglandin E2 produced in response to infection. These afferent signals are integrated and affect the activity of GABAergic inhibitory projection neurons descending from the POA to the dorsomedial hypothalamus (DMH) or to the rostral medullary raphe region (rMR). Attenuation of the descending inhibition by cooling or pyrogenic signals leads to disinhibition of thermogenic neurons in the DMH and sympathetic and somatic premotor neurons in the rMR, which then drive spinal motor output mechanisms to elicit thermogenesis, tachycardia, and cutaneous vasoconstriction. Warming signals enhance the descending inhibition from the POA to inhibit the motor outputs, resulting in cutaneous vasodilation and inhibited thermogenesis. This central thermoregulatory mechanism also functions for metabolic regulation and stress-induced hyperthermia.
Enhanced open-loop but not closed-loop cardiac baroreflex sensitivity during orthostatic stress in humans
Authors: Akimoto Toshinari , Sugawara Jun , Ichikawa Daisuke , Terada Nobuyuki , Fadel Paul J. , Ogoh Shigehiko
Published: September 2011

The neural interaction between the cardiopulmonary and arterial baroreflex may be critical for the regulation of blood pressure during orthostatic stress. However, studies have reported conflicting results: some indicate increases and others decreases in cardiac baroreflex sensitivity (i.e., gain) with cardiopulmonary unloading. Thus the effect of orthostatic stress-induced central hypovolemia on regulation of heart rate via the arterial baroreflex remains unclear. We sought to comprehensively assess baroreflex function during orthostatic stress by identifying and comparing open- and closed-loop dynamic cardiac baroreflex gains at supine rest and during 60° head-up tilt (HUT) in 10 healthy men. Closed-loop dynamic “spontaneous” cardiac baroreflex sensitivities were calculated by the sequence technique and transfer function and compared with two open-loop carotid-cardiac baroreflex measures using the neck chamber system: 1) a binary white-noise method and 2) a rapid-pulse neck pressure-neck suction technique. The gain from the sequence technique was decreased from −1.19 ± 0.14 beats·min−1·mmHg−1 at rest to −0.78 ± 0.10 beats·min−1·mmHg−1 during HUT ( P = 0.005). Similarly, closed-loop low-frequency baroreflex transfer function gain was reduced during HUT ( P = 0.033). In contrast, open-loop low-frequency transfer function gain between estimated carotid sinus pressure and heart rate during white-noise stimulation was augmented during HUT ( P = 0.01). This result was consistent with the maximal gain of the carotid-cardiac baroreflex stimulus-response curve (from 0.47 ± 0.15 beats·min−1·mmHg−1 at rest to 0.60 ± 0.20 beats·min−1·mmHg−1 at HUT, P = 0.037). These findings suggest that open-loop cardiac baroreflex gain was enhanced during HUT. Moreover, under closed-loop conditions, spontaneous baroreflex analyses without external stimulation may not represent open-loop cardiac baroreflex characteristics during orthostatic stress.