bluuebunny/crossref_metadata_2025_split huggingface dataset:
Niobium and tantalum in carbonaceous chondrites: Constraints on the solar system and primitive mantle niobium/tantalum, zirconium/niobium, and niobium/uranium ratio
Authors: Jochum K. p. , Stolz A. j. , Mcorist G. 
Published: February 2010

Abstract— We have determined Nb, Y, and Zr abundances in the carbonaceous chondrites Orgueil (CI), Murray (CM2), Murchison (CM2), Allende (CV3), and Karoonda (CK4), and in the eucrites, Pasamonte and Juvinas, by a recently developed spark source mass spectrometric technique using multiple ion counting (MIC‐SSMS). The abundance of Ta was determined in the same meteorites by radiochemical neutron activation analysis (RNAA). Precision of the MIC‐SSMS and RNAA techniques is ∼3% and ≤ 5%, respectively.The new abundances for CI chondrites are: Nb = 0.247, Ta = 0.0142, Zr = 3.86, Y = 1.56 μg/g; or 0.699, 0.0202, 11.2, and 4.64 atoms/106 Si atoms, respectively. The values agree with earlier compilations, but they are a factor of 2 more precise than earlier analyses. Trace element concentrations in the CM, CV, and CK chondrites are higher than in the CI chondrite Orgueil by about 37, 86, and 120%, respectively, in agreement with the variable absolute contents of refractory lithophile elements in different groups of carbonaceous chondrites.Of particular interest are the chondritic Nb/Ta, Zr/Nb, and Nb/U ratios, because these ratios are important tools for interpreting the chemical evolution of planetary bodies. We obtained Nb/Ta = 17.4 ± 0.5 for the carbonaceous chondrites and the Juvinas‐type eucrites investigated. Though this value is similar to previous estimates, it is much more precise. The same is true for Zr/Nb (15.5 ± 0.2) and Zr/Y (2.32 ± 0.12). In combination with recently published MIC‐SSMS U data for carbonaceous chondrites, we obtained a chondritic Nb/U ratio of 29 ± 2.Because Nb, Ta, Zr, Y, and U are refractory lithophile elements and presumably partitioned into the silicate phase of the Earth during core formation, the elemental ratios may also be used to constrain evolution of the Earth's primitive mantle and, with the more precise determinations fractionation of Nb and Ta during magmatic processes and mantle‐crust interactions, can now be interpreted with greater confidence.
Exploration of quantitative kinetic models for the evaporation of silicate melts in vacuum and in hydrogen
Authors: ALEXANDER C. M. O'D. 
Published: February 2010

Abstract— Two basic approaches (pure component reference (PCR) and equilibrium reference (EQR)) to modeling silicate melt evaporation are explored. The PCR model calculates the maximum possible evaporation rates of the pure oxides from their equilibrium vapor pressures and rescales these rates according to the activities of the oxides in the silicate melts and the melt densities. The EQR model calculates the maximum possible evaporation rates based on the equilibrium vapor pressures of the melts. Differences between the calculated and experimentally determined evaporation rates are accounted for with evaporation (αevap) coefficients that are only dependent on temperature. Two versions of the PCR model, Cases 1 and 2, are explored to try to resolve apparently contradictory conclusions about the composition of the evaporating species based on Mg and Si isotope fractionation during evaporation (species are not in thermodynamic equilibrium proportions) and direct measurements of gas species in Langmuir experiments (species are in roughly equilibrium proportions). The Case 2 and EQR models cannot explain the observed isotope fractionations unless evaporation occurred under non‐Rayleigh conditions, either because there was significant recondensation during the experiments or because diffusion was playing a limiting role.Whether or not the role of diffusion is included, the PCR and EQR models are able to reproduce the elemental results of evaporation experiments of “chondritic” melts from temperatures of 1700 to 2000 °C, and up to mass losses of about 95%. However, the models underestimate absolute evaporation rates in very Ca‐ and Al‐rich melts. This may reflect errors in the model used to estimate oxide activities. The EQR model can only reproduce the observed evaporation behavior of Na if, unlike the other oxides, its αevap coefficient is close to unity.Based on available diffusion data, diffusion is not slow enough in “chondritic” or forsteritic melts to explain the isotopic fractionations of Mg and O in the evaporation experiments, but it may play a role in limiting Si isotope fractionation. Provided recondensation was not a significant factor in the experiments, at present PCR Case 1 appears to be the best model if both the Langmuir and the isotopic fractionation experiments are to be explained.
Formation of orange hibonite, as inferred from some Allende inclusions
Authors: SIMON S. B. , DAVIS A. M. , GROSSMAN L. 
Published: February 2010

Abstract— We studied three fluffy Type A refractory inclusions from Allende that contain orange hibonite. The melilite in the present samples is very Al‐rich, averaging Åk6, Åk14, and Åk12 in the three samples studied. Hibonite in two inclusions, unlike that in Murchison, has low rare earth element abundances of <10 × CI; in the other inclusion, the hibonite, melilite and perovskite have Group II‐like patterns. The hibonite and melilite in all three inclusions studied have excess 26Mg consistent with (26Al/27Al)I = 5 × 10−5. Much of the hibonite and some of the spinel in these inclusions is corroded. These phases are found enclosed in melilite, but based on bulk compositions and phase equilibria, hibonite should not be an early‐crystallizing phase in these inclusions. We conclude that the hibonite and probably some of the spinel is relic. Reversely zoned melilite, rounded spinel and isotopically heavy Mg in the inclusions probably reflect reheating events that involved melting and evaporation. Alteration of the gehlenitic melilite gave rise to some rare phases, including corundum and nearly pure CaTs pyroxene.Studies have shown that blue hibonite contains Ti3+ while orange hibonite does not (Ihinger and Stolper, 1986; Beckett et al., 1988). Orange hibonite formed either under oxidizing conditions (such as at oxygen fugacities at least seven orders of magnitude greater than that of a solar gas at 1700 K), or under conditions reducing enough (e.g., solar) that it contained Ti3+, which was later oxidized in situ. Although V and Ce oxides are volatile at the temperature and range of oxygen fugacities at which orange hibonite is known to be stable, we find that (a) the hibonite is V‐rich (∼1 wt% V2O3) and (b) there are no negative Ce anomalies in Allende hibonite. This indicates that the hibonite did not form by condensation under oxidizing conditions. In addition, there are slight excesses of Ti + Si cations relative to Mg + Fe cations (up to 0.1 of 0.8 cations per 19 oxygen anions), probably reflecting the original presence of Ti3+. The results of this study strongly support the suggestion (Ihinger and Stolper, 1986) that Allende hibonite originally formed under reducing conditions and was later oxidized. Oxygen fugacities within ∼2–3 orders of magnitude of that of a solar gas are implied; otherwise, strong Ce and V depletions would be observed.
Formation of resurge gullies at impacts at sea: The Lockne crater, Sweden
Authors: DALWIGK Ilka von , ORMÖ Jens 
Published: February 2010

Abstract— The Lockne crater in Sweden is a marine‐target crater, formed in a shelf sea, approximately 460 Ma ago. The crater structure consists of an inner crater surrounded by an outer, inclined surface that extends to almost 12 km from the center.Marine craters differ in several respects from craters formed on land. One special feature is the formation of resurge gullies excavated by the erosional force of the resurging sea water after the impact. The formation of these gullies strongly depends on the ratio crater‐rim height to water depth, as well as on the size of the impact structure. Such gullies are known from very few marine‐target craters. At the Lockne impact site, four gullies are identified, each of which cuts radially through the rim of the outer crater.The rapid collapse of that part of the crater cavity, which formed in the seawater, resulted in forceful flooding of the crater. The resurging seawater not only contained fallback‐ejecta; on its way towards the cavity on the sea‐bottom it incorporated fractured lithologies from the sea‐bottom as well. This entrained material disintegrated during transport and constitutes today the dominantly monomict lower part of the resurge sequence. The resurge flood was highly turbulent, highly erosive, and developed to a probable hyperconcentrated flow or a possible water flood. The erosion in the gullies proceeded as headward erosion down to the transition zone between the brecciated and the less disintegrated crystalline basement.
A new metal‐rich chondrite grouplet
Authors: WEISBERG Michael K. , PRINZ Martin , CLAYTON Robert N. , MAYEDA Toshiko K. , SUGIURA Naoji , ZASHU Shigeo , EBIHARA Mitsuru 
Published: February 2010

Abstract— A new grouplet of primitive, metal‐rich chondrites, here called the CB (C, carbonaceous; B, bencubbinite) chondrites, has been recognized. It includes Bencubbin, Weatherford, Hammadah al Hamra (HH) 237 and Queen Alexandra Range (QUE) 94411, paired with QUE 94627. Their mineral compositions, as well as their oxygen and nitrogen isotopic compositions, indicate that they are closely related to the CR and CH chondrites, all of which are members of the more inclusive CR clan. CB chondrites have much greater metal/silicate ratios than any other chondrite group, widely increasing the range of metal/silicate fractionation recorded in solar nebular processes. They also have the greatest moderately volatile lithophile element depletions of any chondritic materials. Metal has compositional trends and zoning patterns that suggest a primitive condensation origin, in contrast with metal from other chondrite groups. CB chondrites, as well as other CR clan chondrites, have much heavier nitrogen (higher 15N/14N) than that in other chondrite groups. The primitive characteristics of the CB chondrites suggest that they contain one of the best records of early nebular processes.Another chondrite, Grosvenor Mountains 95551, is petrographically similar to the CB chondrites, but its mineral and oxygen and nitrogen isotope compositions indicate that it formed from a different nebular reservoir.
Noble gases in enstatite chondrites I: Exposure ages, pairing, and weathering effects
Authors: PATZER Andrea , SCHULTZ Ludolf 
Published: February 2010

Abstract— Cosmic‐ray exposure ages calculated from cosmogenic noble gas nuclides are reported for 57 enstatite (E) chondrites, 43 of them were measured for the first time. With a total of 62 individual E chondrites (literature and this data, corrected for pairing) the observed spectrum of ages ranges between 0.07 and 66 Ma. Three clusters seem to develop at about 3.5, 8, and 25 Ma, respectively. Since the uncertainty of ages is estimated to be ∼20% (in contrast to 10 to 15% for ordinary chondrites) and the number of examined samples is still comparatively small, these peaks have to be confirmed by more measurements. Regarding the two subgroups, EH and EL chondrites, no systematic trend is apparent in the distribution of cosmic‐ray exposure ages.Several E chondrites yield significantly lower 38Ar ages compared to those calculated from cosmogenic 3He and 21Ne. For these E chondrites, we suggest a reduction of cosmogenic 38Ar as a result of weathering. In order to prove the possible influence of terrestrial alteration on the cosmogenic noble gas record of E‐chondritic material, we simulated terrestrial weathering in an experiment of 12 weeks duration. The treatment showed that a significant amount of cosmogenic 38Ar is lost on Earth by the influence of water.
Direct Detection of Methicillin Resistance in
Staphylococcus aureus
in Blood Culture Broth by Use of a Penicillin Binding Protein 2a Latex Agglutination Test
Authors: Qian Qinfang , Venkataraman Lata , Kirby James E. , Gold Howard S. , Yamazumi Toshiaki 
Published: February 2010

ABSTRACT

We studied the utility of performing a penicillin binding protein 2a latex agglutination (PBP-LA) assay directly on Bactec blood culture broth samples containing
Staphylococcus aureus
to rapidly detect methicillin resistance. The sensitivity, specificity, positive predictive value, and negative predictive value of this method were 94.1%, 97.5%, 98%, and 92.9%, respectively.
InhA1, NprA, and HlyII as Candidates for Markers To Differentiate Pathogenic from NonpathogenicBacillus cereusStrains
Authors: Cadot Céline , Tran Seav-Ly , Vignaud Marie-Léone , De Buyser Marie-Laure , Kolstø Anne-Brit , Brisabois Anne , Nguyen-Thé Christophe , Lereclus Didier , Guinebretière Marie-Hélène , Ramarao Nalini 
Published: February 2010

ABSTRACTBacillus cereusis found in food, soil, and plants, and the ability to cause food-borne diseases and opportunistic infection presumably varies among strains. Therefore, measuring harmful toxin production, in addition to the detection of the bacterium itself, may be key for food and hospital safety purposes. All previous studies have focused on the main known virulence factors, cereulide, Hbl, Nhe, and CytK. We examined whether other virulence factors may be specific to pathogenic strains. InhA1, NprA, and HlyII have been described as possibly contributing toB. cereuspathogenicity. We report the prevalence and expression profiles of these three new virulence factor genes among 57B. cereusstrains isolated from various sources, including isolates associated with gastrointestinal and nongastrointestinal diseases. Using PCR, quantitative reverse transcriptase PCR, and virulencein vivoassays, we unraveled these factors as potential markers to differentiate pathogenic from nonpathogenic strains. We show that thehlyIIgene is carried only by strains with a pathogenic potential and that the expression levels ofinhA1andnprAare higher in the pathogenic than in the nonpathogenic group of strains studied. These data deliver useful information about the pathogenicity of variousB. cereusstrains.
Human Rhinovirus 14 Enters Rhabdomyosarcoma Cells Expressing ICAM-1 by a Clathrin-, Caveolin-, and Flotillin-Independent Pathway
Authors: Khan Abdul Ghafoor , Pickl-Herk Angela , Gajdzik Leszek , Marlovits Thomas C. , Fuchs Renate , Blaas Dieter 
Published: February 2010

ABSTRACTIntercellular adhesion molecule 1 (ICAM-1) mediates binding and entry of major group human rhinoviruses (HRVs). Whereas the entry pathway of minor group HRVs has been studied in detail and is comparatively well understood, the pathway taken by major group HRVs is largely unknown. Use of immunofluorescence microscopy, colocalization with specific endocytic markers, dominant negative mutants, and pharmacological inhibitors allowed us to demonstrate that the major group virus HRV14 enters rhabdomyosarcoma cells transfected to express human ICAM-1 in a clathrin-, caveolin-, and flotillin-independent manner. Electron microscopy revealed that many virions accumulated in long tubular structures, easily distinguishable from clathrin-coated pits and caveolae. Virus entry was strongly sensitive to the Na+/H+ion exchange inhibitor amiloride and moderately sensitive to cytochalasin D. Thus, cellular uptake of HRV14 occurs via a pathway exhibiting some, but not all, characteristics of macropinocytosis and is similar to that recently described for adenovirus 3 entry via αvintegrin/CD46 in HeLa cells.
Dynamics of Influenza Virus Infection and Pathology
Authors: Saenz Roberto A. , Quinlivan Michelle , Elton Debra , MacRae Shona , Blunden Anthony S. , Mumford Jennifer A. , Daly Janet M. , Digard Paul , Cullinane Ann , Grenfell Bryan T. , McCauley John W. , Wood James L. N. , Gog Julia R. 
Published: February 2010

ABSTRACT
A key question in pandemic influenza is the relative roles of innate immunity and target cell depletion in limiting primary infection and modulating pathology. Here, we model these interactions using detailed data from equine influenza virus infection, combining viral and immune (type I interferon) kinetics with estimates of cell depletion. The resulting dynamics indicate a powerful role for innate immunity in controlling the rapid peak in virus shedding. As a corollary, cells are much less depleted than suggested by a model of human influenza based only on virus-shedding data. We then explore how differences in the influence of viral proteins on interferon kinetics can account for the observed spectrum of virus shedding, immune response, and influenza pathology. In particular, induction of high levels of interferon (“cytokine storms”), coupled with evasion of its effects, could lead to severe pathology, as hypothesized for some fatal cases of influenza.
Rabies Virus Nucleoprotein Functions To Evade Activation of the RIG-I-Mediated Antiviral Response
Authors: Masatani Tatsunori , Ito Naoto , Shimizu Kenta , Ito Yuki , Nakagawa Keisuke , Sawaki Yoshiharu , Koyama Hiroyuki , Sugiyama Makoto 
Published: February 2010

ABSTRACT

The rabies virus Ni-CE strain causes nonlethal infection in adult mice after intracerebral inoculation, whereas the parental Nishigahara (Ni) strain kills mice. We previously reported that the chimeric CE(NiN) strain with the N gene from the Ni strain in the genetic background of the Ni-CE strain kills adult mice, indicating that the N gene is related to the different pathogenicities of Ni and Ni-CE strains. In the present study, to obtain an insight into the mechanism by which the N gene determines viral pathogenicity, we compared the effects of Ni, Ni-CE, and CE(NiN) infections on host gene expressions using a human neuroblastoma cell line. Microarray analysis of these infected cells revealed that the expression levels of particular genes in Ni- and CE(NiN)-infected cells, including beta interferon (IFN-β) and chemokine genes (i.e., CXCL10 and CCL5) were lower than those in Ni-CE-infected cells. We also demonstrated that Ni-CE infection activated the interferon regulatory factor 3 (IRF-3)-dependent IFN-β promoter and induced IRF-3 nuclear translocation more efficiently than did Ni or CE(NiN) infection. Furthermore, we showed that Ni-CE infection, but not Ni or CE(NiN) infection, strongly activates the IRF-3 pathway through activation of RIG-I, which is known as a cellular sensor of virus infection. These findings indicate that the N protein of rabies virus (Ni strain) has a function to evade the activation of RIG-I. To our knowledge, this is the first report that the
Mononegavirales
N protein functions to evade induction of host IFN and chemokines.
Contribution of Vaccine-Induced Immunity toward either the HA or the NA Component of Influenza Viruses Limits Secondary Bacterial Complications
Authors: Huber Victor C. , Peltola Ville , Iverson Amy R. , McCullers Jonathan A. 
Published: February 2010

ABSTRACT
Secondary bacterial infections contribute to morbidity and mortality from influenza. Vaccine effectiveness is typically assessed using prevention of influenza, not secondary infections, as an endpoint. We vaccinated mice with formalin-inactivated influenza virus vaccine preparations containing disparate HA and NA proteins and demonstrated an ability to induce the appropriate anti-HA and anti-NA immune profiles. Protection from both primary viral and secondary bacterial infection was demonstrated with vaccine-induced immunity directed toward either the HA or the NA. This finding suggests that immunity toward the NA component of the virion is desirable and should be considered in generation of influenza vaccines.
Examining the public refusal to consent to DNA biobanking: empirical data from a Swedish population-based study
Authors: Melas Philippe A , Sjöholm Louise K , Forsner Tord , Edhborg Maigun , Juth Niklas , Forsell Yvonne , Lavebratt Catharina 
Published: February 2010

ObjectivesTo investigate empirically the motivations for not consenting to DNA biobanking in a Swedish population-based study and to discuss the implications.DesignStructured questionnaires and semistructured interviews.SettingA longitudinal epidemiological project (PART) ongoing since 1998 in Stockholm, Sweden. The DNA-collection wave took place during 2006–7.Participants903 individuals completed the questionnaire (participation rate 36%) and 23 were interviewed. All individuals had participated in both non-genetic waves of the project, but refused to contribute saliva samples during the DNA-collection wave.Main outcome measuresMotivations behind refusing to consent to DNA biobanking, with subsequent focus on participants' explanations regarding this unwillingness.ResultsPublic refusal to consent to DNA biobanking, as revealed by the questionnaire, was mainly explained by a lack of personal relevance of DNA contribution and feelings of discomfort related to the DNA being used for purposes other than the respective study. Interviews of individuals representing the second motivation, revealed a significant mistrust of DNA biobank studies. The underlying beliefs and attitudes were associated with concerns about integrity, privacy, suspiciousness and insecurity. However, most interviewees were supportive of genetic research per se and interpreted their mistrust in the light of distressing environmental influences.ConclusionThe results suggest a need for guidelines on benefit sharing, as well as trustworthy and stable measures to maintain privacy, as a means for increasing personal relevance and trust among potential participants in genetic research. Measures taken from biobanks seem insufficient in maintaining and increasing trust, suggesting that broader societal measures should be taken.
Post-recruitment confirmation of informed consent by SMS: Figure 1
Authors: Gulbrandsen Pål , Jensen Bård Fossli 
Published: February 2010

BackgroundTo allow patients to reflect about a decision to participate in a clinical trial, guidelines suggest a 24-h delay from when they are informed about the trial to when they give consent. In certain clinical settings, this is likely to hamper recruitment.MethodAfter oral and written information about the trial has been given in person, the patient signs the declaration of consent knowing that they will be asked again after 24 h whether they confirm or regret the decision. This procedure can be done by SMS. The investigators must document the response. The procedure was tried in a study in which the doctors were randomly assigned to receive a clinical communication skills course, and encounters with patients were videotaped before and after the course.Results553 patients were approached, 530 (95.8%) gave initial consent, eight of these later regretted their consent.DiscussionThe low level of regrets suggests this is an acceptable procedure for patients.Trial registrationThe RCT was registered before initiation – registration # ISRCTN22153332.