Deformation of Ordinary Chondrite Under Very Reducing Conditons: Implications for Liquid Metal Compositions, HSE Partitioning and Enstatite Chondrites

NASA Astrophysics Data System (ADS)

Rushmer, T.; Corgne, A.

2008-12-01

One important method in which to gain insight into metallic liquid compositions and their ability to control HSE (highly siderophile element) distribution is through experimentation. Deformation experiments can additionally provide information into mechanisms and chemical consequences of dynamic liquid metal segregation under a variety of conditions. We report results on metallic liquid HSE compositions and their distribution from a set of deformation experiments on a natural H6 ordinary chondrite, performed under very reducing conditions and a series of phase equilibria experiments focused on HSE partitioning between Si-rich and S-rich Fe molten alloys. The deformation experiments were conducted at temperatures between 925°C and 950°C, at 1.3 GPa confining pressure with a strain rate of 10-4/s. Major element analyses of both silicate and metal phases show that they are considerably reduced and the typically lithophile elements are behaving like siderophiles. Fe-Ni-Si compositions are found in the shear zones produced during the deformation experiment. Metallic compositions also include (Mg,Fe,Ca)S, Fe-Ni-Si, FeP, and Fe-Ni-S quench metal. Silicate phases include forsterite (Fo92-96) and enstatite (En98). Highly siderophile element (HSE) concentrations have been measured in the sulphide ((Fe,Mg,Ca)S) and metal (Fe- Ni-Si) phases by LA-ICPMS and compared with results from an earlier set of experiments on the same material but which were not performed under reducing conditions. The partitioning of the PGE is modified by the changing conditions with elements such as Ir and Os having higher DMetal/Sulphide values under reducing conditions. Partitioning experiments between molten FeS and Ni-, Si-bearing molten Fe were performed at 1.5-5.0 GPa and 1500-1750° to further investigate this observation. The starting material is synthetic, doped with a range of trace and HSE elements. The results confirm the preference of the HSE for the metallic phase with DMetal/Sulphide > 100 in most cases, in contrast to Cu and Ag, which have D values near or below 1, respectively. Our results also suggest the possibility of significant PGE fractionation since D values are larger for Ir and Os and smaller for Pd and Au, with Pt, Ru, Rh having intermediate values. It is not clear with the present data set whether T and P variations can affect significantly HSE partitioning. These results have been applied to the most naturally reduced material we know, the Enstatite chondrites. Several E chondrites have bulk HSE data available, but no HSE data available on sulphide and metallic phases themselves. We have now a set of HSE data for individual metallic phases in several enstatite chondrites, both EH and ELs. The bulk data show that for elements such as Os and Pd, the abundances are positively correlated and overall Pd is much higher in abundance. We find in the experiments that DPd ranges between 10-100, but do not fully explain the bulk trends. Additional phases, such as FeP have therefore been analyzed and we find that Pd is concentrated in FeP and the presence of schreibersite may help explain the high Pd ratios (e.g. Pd/Ir) observed in the Enstatite chondrites.

Highly Sideophile Element Abundance Constraints on the Nature of the Late Accretionary Histories of Earth, Moon and Mars

NASA Technical Reports Server (NTRS)

Walker, R. J.; Puchtel, I. S.; Brandon, A. D.; Horan, M. F.; James, O. B.

2007-01-01

The highly siderophile elements (HSE) include Re, Os, Ir, Ru, Pt and Pd. These elements are initially nearly-quantitatively stripped from planetary silicate mantles during core segregation. They then may be re-enriched in mantles via continued accretion sans continued core segregation. This suite of elements and its included long-lived radiogenic isotopes systems (Re-187 (right arrow) Os-187; Pt-190 (right arrow) Os-186) can potentially be used to fingerprint the characteristics of late accreted materials. The fingerprints may ultimately be useful to constrain the prior nebular history of the dominant late accreted materials, and to compare the proportion and genesis of late accretionary materials added to the inner planets. The past ten years have seen considerable accumulation of isotopic and compositional data for HSE present in the Earth's mantle, lunar mantle and impact melt breccias, and Martian meteorites. Here we review some of these data and consider the broader implications of the compiled data.

182W and HSE constraints from 2.7 Ga komatiites on the heterogeneous nature of the Archean mantle

NASA Astrophysics Data System (ADS)

Puchtel, Igor S.; Blichert-Toft, Janne; Touboul, Mathieu; Walker, Richard J.

2018-05-01

While the isotopically heterogeneous nature of the terrestrial mantle has long been established, the origin, scale, and longevity of the heterogeneities for different elements and isotopic systems are still debated. Here, we report Nd, Hf, W, and Os isotopic and highly siderophile element (HSE) abundance data for the Boston Creek komatiitic basalt lava flow (BCF) in the 2.7 Ga Abitibi greenstone belt, Canada. This lava flow is characterized by strong depletions in Al and heavy rare earth elements (REE), enrichments in light REE, and initial ε143Nd = +2.5 ± 0.2 and intial ε176Hf = +4.2 ± 0.9 indicative of derivation from a deep mantle source with time-integrated suprachondritic Sm/Nd and Lu/Hf ratios. The data plot on the terrestrial Nd-Hf array suggesting minimal involvement of early magma ocean processes in the fractionation of lithophile trace elements in the mantle source. This conclusion is supported by a mean μ142Nd = -3.8 ± 2.8 that is unresolvable from terrestrial standards. By contrast, the BCF exhibits a positive 182W anomaly (μ182W = +11.7 ± 4.5), yet is characterized by chondritic initial γ187Os = +0.1 ± 0.3 and low inferred source HSE abundances (35 ± 5% of those estimated for the present-day Bulk Silicate Earth, BSE). Collectively, these characteristics are unique among Archean komatiite systems studied so far. The deficit in the HSE, coupled with the chondritic Os isotopic composition, but a positive 182W anomaly, are best explained by derivation of the parental BCF magma from a mantle domain characterized by a predominance of HSE-deficient, differentiated late accreted material. According to the model presented here, the mantle domain that gave rise to the BCF received only ∼35% of the present-day HSE complement in the BSE before becoming isolated from the rest of the convecting mantle until the time of komatiite emplacement at 2.72 Ga. These new data provide strong evidence for a highly heterogeneous Archean mantle in terms of absolute HSE abundances and W isotopic composition, and also indicate slow mixing, on a timescale of at least 1.8 billion years. Additionally, the data are consistent with a stagnant-lid plate tectonic regime in the Hadean and Archean, prior to the onset of modern-style plate tectonics.

Highly Siderophile Elements as Tracers for the Subcontinental Mantle Evolution Beneath the Southwestern USA: The San Carlos and Kilbourne Hole Peridotite Xenoliths Revisited

NASA Technical Reports Server (NTRS)

vanAcken, D.; Brandon, A. D.; Peslier, A. H.; Lee, C.-T. A.

2010-01-01

Peridotite xenoliths from San Carlos, Arizona, and Kilbourne Hole, New Mexico, have been studied since the 1970 s to give insights into melting and metasomatism in the subcontinental mantle beneath the southwestern USA. More recently, the highly siderophile elements (HSE; Os, Ir, Ru, Rh, Pt, Pd, and Re) and the included Re-Os isotope system have been established as powerful tools for the study of mantle processes because of their range in compatibility during mantle melting and their siderophile and chalcophile geochemical behavior. Model aluminachron Re-Os ages for San Carlos and Kilbourne Hole, as well as for the nearby Dish Hill and Vulcan's Throne sites, give consistent depletion ages of around 2.2 Ga. This age can be interpreted as a single large scale mantle melting event linked to crustal formation and continental growth under the southwestern USA. Highly siderophile elements, however, may be added to depleted peridotites via melt-rock interaction, especially the more incompatible and hence mobile Pt, Pd, and Re. This may result in overprinting of the signature of melt extraction, thus abating the usefulness of Re-Os mantle extraction model ages. A comprehensive characterization of the suite of mantle xenoliths from the SW USA in terms of HSE concentrations is thus necessary to re-assess the Re-Os system for dating purposes. San Carlos peridotites are depleted to moderately fertile, as indicated by their bulk Al2O3 contents between 0.66 wt% and 3.13 wt%. Bulk Os-187/Os-188 in San Carlos peridotites range from 0.1206 to 0.1357. In contrast, Kilbourne Hole peridotites tend to be more fertile with Al2O3 between 2.11 and 3.78 wt%, excluding one extremely depleted sample with 0.30 wt% Al2O3, and have Os-187/Os-188 between 0.1156 and 0.1272, typical for mantle peridotites. No large fractionation between the more compatible HSE Os, Ir, and Ru are observed. The more incompatible HSE Re, Pd, and to a minor extent, Pt, however, are depleted in a number of samples by factors of up to 4 for Pt, 6 for Pd, and 20 for Re, compared to primitive mantle estimates. This is in agreement with previous studies from the same locales, which demonstrated the presence of different populations of mantle xenoliths having undergone various degrees of melt extraction. The depletion of the more incompatible elements (Re, Pd, and Pt) also suggests that the HSE budgets of the SW USA peridotites were primarily established by extraction of basaltic melt, and reflect only minor influence from later episodes of metasomatism. Model Re-Os ages obtained from San Carlos and Kilbourne Hole xenoliths may thus reflect ages of crustal formation and mantle depletion in the SW USA region.

Significance of the whole rock Re-Os ages in cryptically and modally metasomatised cratonic peridotites: Constraints from HSE-Se-Te systematics

NASA Astrophysics Data System (ADS)

Luguet, Ambre; Behrens, Melanie; Pearson, D. Graham; König, Stephan; Herwartz, Daniel

2015-09-01

The Re-Os isotopic system is the geochronometer of choice to constrain the timing of lithospheric mantle root formation and reconstruct the evolution of Earth's dynamics from the "mantle" perspective. In order to constrain the effects of metasomatic processes on the Re-Os isotopic system, eleven peridotites from the Letlhakane kimberlite pipe were investigated for whole rock major and trace elements, highly siderophile elements (HSE), Se, Te and 187Os/188Os signatures. These spinel peridotites (SP), garnet peridotites (GP), garnet-phlogopite peridotites (GPP) and phlogopite peridotites (PP) experienced cryptic metasomatism and the GP-GPP-PP additionally constitute a sequence of increasing modal metasomatism. The cryptically metasomatised SP appear devoid of base metal sulphides (BMS) and show suprachondritic Se/Te ratios (15-40) and extremely Pd- and Pt-depleted HSE patterns. These features are characteristic of high-degree partial melting residues. Their 187Os/188Os signatures are thus considered to be inherited from the partial melting event. This implies a Neoarchean (2.5-2.8 Ga, TRD eruption) stabilisation of the Letlhakane mantle root and supports the Letlhakane mantle root being a westerly extension of the Zimbabwe cratonic root. The modally metasomatised peridotites contain BMS whose abundance significantly increases from the GPP to the GP and PP. The BMS-poor GPP are only slightly richer in Pt and Pd than the BMS-free SP but have similarly high Se/Te ratios. The BMS-rich GP and PP exhibit significant enrichments in Pt, Pd, Se, Te resulting in HSE-Se-Te signatures similar to that of the Primitive Upper Mantle (PUM). Addition of 0.001-0.05 wt.% metasomatic BMS ± PGM (platinum group minerals, i.e., Pt-tellurides) to highly refractory residues, such as the Letlhakane SP, reproduce well the HSE-Se-Te systematics observed in the BMS-poor and BMS-rich modally metasomatised peridotites. In the GPP, the negligible addition of metasomatic BMS ± PGM did not disturb the 187Os/188Os signatures, indicating TRD eruption ages identical with those of the SP. By contrast, the PP and GP, which suffered significant BMS ± PGM addition, have 187Os/188Os considerably shifted toward more radiogenic values. As a result, unrealistically young TRD eruption ages are obtained that cannot be used to constrain the time frame of the stabilisation of the cratonic roots and the mechanisms of craton formation. The Se-Te and incompatible HSE (i.e., Pt, Pd) are powerful geochemical tools to assess the robustness of the Re-Os isotopic system in mantle peridotites. Specifically, Se/Te and Pd/Ir ratios provide complementary insights into the complex metasomatic history of mantle peridotites. The Se/Te ratio is very sensitive to Os-free PGM metasomatism producing highly variable Se/Te >15 at low, relatively constant Pd/Ir< 0.4 but does not affect the 187Os/188Os systematics. This contrasts with BMS metasomatism, where Pd/Ir becomes more variable (>0.4), at constant but low Se/Te <10 and which is accompanied by modification of the Os isotopic composition of the host peridotite. As they are sensitive indicators of BMS ± PGM metasomatism, HSE, Se and Te should be systematically considered when investigating the timing of stabilisation of lithospheric mantle and its petrogenetic history. This would allow a more robust assessment of the Re-Os ages obtained and provide firmer constraints on the evolution and formation of Archean cratons and early Earth dynamics.

Highly Siderophile Elements in Shocked and Unshocked Chondrites

NASA Technical Reports Server (NTRS)

Horan, M. F.; Walker, R. J.; Rubin, A. E.

2001-01-01

High precision abundances of Re, Os, Pt, Ir, Ru, and Pd are combined with Re-Os isotopic data to demonstrate that HSE provide a distinctive fingerprint for each of the chondrite groups. Additional information is contained in the original extended abstract.

Highly siderophile element constraints on the genesis of Azorean lavas

NASA Astrophysics Data System (ADS)

Waters, C. L.; Watanabe, S.; Olson, K. M.; Walker, R. J.; Widom, E.; Hanan, B. B.; Day, J. M.

2013-12-01

Ocean island basalts (OIB) from the Azores archipelago show incompatible element and Sr-Nd-Hf-Pb isotopic heterogeneity both among different islands and within individual islands. This heterogeneity has commonly been attributed to the presence of a mantle plume delivering diverse recycled materials--including terrigenous sediments, metasomatized subcontinental lithosphere, and oceanic crust--to the melting region beneath the Azores (Turner et al., 1997; Widom and Shirey, 1996; Beier et al., 2007). Despite an abundance of datasets including major and trace element and Sr, Nd, Hf, and Pb isotopic compositions, the origin of elemental and isotopic heterogeneity in the Azores remains vigorously debated. We report new highly siderophile element (HSE: Os, Ir, Pd, Pt, Ru, Re) abundance data alongside major and trace element abundance and Nd-Hf-Os-Pb isotope data for a suite of high MgO (8-17 wt%) lavas from the islands of Sao Miguel, Pico, Faial, and Terceira. These lavas span most of the range of incompatible trace element and Nd-Hf-Pb isotopic heterogeneity observed for the Azores. Because HSEs are largely controlled by sulfide, they provide an alternative to the classic perspective of OIB petrogenesis derived from lithophile elements. The results show distinct fractionation patterns for HSEs from different islands at a similar range of MgO contents. Lavas from Pico and Faial have lower absolute HSE abundances (total HSE abundances ~0.001 × CI chondrite; Ir=0.014-0.133 ppb) and are generally more homogeneous than lavas from Terceira and Sao Miguel (total HSE = ~0.003 × CI chondrite; Ir=0.038-0.657 ppb)). Faial and Pico lavas (IrN* = 0.8×0.3, where IrN* = IrN/[(OsN+RuN)0.5] x 100) also commonly lack the positive relative enrichment in Ir observed in Terceira and Sao Miguel lavas (IrN* = 2.4 ×1.1). In contrast to previous studies of OIB in which HSEs are observed to positively correlate with MgO (e.g., Day, 2013), only Re correlates with MgO, as expected given its moderate incompatibility in silicate systems. All other HSEs show wide variability at similar MgO, broadly correlate with each other, yet do not correlate with Nd-Hf-Pb isotope compositions. Thus, we interpret HSE variability to reflect variations in mantle sulfide source composition and sulfide melting beneath different islands in the Azores hotspot.

Geochemistry of impact glasses and target rocks from the Zhamanshin impact structure, Kazakhstan: Implications for mixing of target and impactor matter

NASA Astrophysics Data System (ADS)

Jonášová, Šárka; Ackerman, Lukáš; Žák, Karel; Skála, Roman; Ďurišová, Jana; Deutsch, Alexander; Magna, Tomáš

2016-10-01

Internal structure and element chemistry including contents of highly siderophile elements (HSE) and Os isotope ratios have been studied in target rocks and several groups of impact glasses of the Zhamanshin impact structure, Kazakhstan. These include larger irregularly-shaped fragments and blocks of impact glass (zhamanshinites), and three types of tektite-like splash-form glasses, part of fallback ejecta. These glassy objects typically are up to 30 mm large and are shaped as teardrops, irregularly bent and curved glass rods and fibers. They can be subdivided into acidic types (irghizites; typically 69-76 wt.% SiO2), basic splash-forms (typically 53-56 wt.% SiO2), and rarely occurring highly inhomogeneous composites with abundant mineral inclusions. A comparison with the target rocks shows that zhamanshinites and basic splash-forms usually have no detectable admixture of the projectile matter, indicated by major and trace elements as well as highly siderophile element contents, with the exception of one sample containing Fe-, Cr-, Ni- and Ti-enriched particles and elevated HSE contents. In contrast, irghizites exhibit clear admixture of the projectile matter, which was incorporated by complex processes accompanied by strong element fractionations. Microscopic investigations confirm that irghizites were formed mainly by coalescence of smaller molten glass droplets sized typically below 1 mm. Irghizites exhibit significant enrichments in Ni, Co and Cr, whose concentrations are locally elevated in the rims of the original small droplets. A portion of these elements and also part of Fe and Mn and other elements were derived from the impactor, most likely a Ni-rich carbonaceous chondrite. The contents of HSE are low and strongly fractionated, with moderate depletions of Pt and Pd and strong depletions of other HSE with respect to chondritic element ratios. Osmium shows the strongest depletion, likely related to the presence of oxygen in the post-impact atmosphere causing strong Os loss through volatilization. One composite splash-form contains Fe-Ni-S inclusions and exhibits a less fractionated HSE pattern suggesting the lowest degree of melting, volatilization and condensation. The observed structural and microchemical features of irghizites are interpreted to reflect variable proportions of the uppermost target sediments and the projectile matter, with HSE element ratios influenced by evaporation and condensation processes, and differences in volatility of individual HSE elements and/or their compounds. Two possible pathways of incorporation of the projectile matter into the irghizites include either re-condensation of evaporated projectile matter on the surface of glass droplets, or incorporation of less chemically fractionated microparticles dispersed by the explosion.

Highly Siderophile Element Abundances in Martian Meteorites

NASA Technical Reports Server (NTRS)

Jones, J. H.; Neal, C. R.; Ely, J. C.

2001-01-01

Critical evaluation of new and literature data for highly siderophile elements (HSE) in Martian (SNC) meteorites allows several first order conclusions to be drawn. (i) Re concentrations in SNC meteorites are nearly constant (within a factor of two) and do not correlate with rock type. Exceptions to this rule are Chassigny and Dar al Gani (DaG) 476, both of which are inferred to have experienced terrestrial Re contamination. (ii) Fractionations between Rh and Pd are small. Excluding Shergotty, the Rh/Pd ratio of the SNC suite is 0.22\\pm0.05. (iii) Os and Ir contents vary by about four orders of magnitude; and positive correlations with MgO, Cr, and Ni suggest that these variations are not controlled by sulfide fractionation. A possible exception is the orthopyroxenite ALH84001, whose HSE's (including Ni, which is compatible in opx) are very low. (iv) Zagami, Shergotty, and Nakhla have nearly identical HSE signatures. Shergotty and Zagami have experienced assimilation-fractional crystallization (AFC) and have "crustal" Sr and Nd isotopic signatures. Conversely, the Nakhla parent was a small degree partial melt of a depleted mantle that interacted little with the Martian crust. These observations suggest that "evolved" HSE signatures can be produced by either fractional crystallization or small degrees of partial melting. (v) Chassigny and other mafic SNC's have HSE signatures that are very distinct from those of Nakhla-Zagami-Shergotty. The HSE elemental ratios of mafic SNC's approach chondritic, implying that the Martian mantle has nearly chondritic relative abundances of the HSE's. (vi) This chondritic HSE signature is observed in SNC's of various ages, suggesting that this is an ancient feature that has not evolved over time. (vii) No correlation is observed between HSE's and signatures of crustal contamination (e.g., Sr isotopes), indicating that the HSE signatures of the SNC suite are not derived from the crust. (vii) The Ru/Pd for the SNC suite ratio is about 0.5 chondritic. We attribute this depletion of Ru to the presence of spinel in the SNC source regions. (viii) Assignment of this depletion of Ru to spinel seems to also imply that spinel is not the cause of Os and Ir fractionations, requiring some other mafic phase to account for the observed variations. -----.

Ancient impactor components preserved and reworked in martian regolith breccia Northwest Africa 7034

NASA Astrophysics Data System (ADS)

Goderis, Steven; Brandon, Alan D.; Mayer, Bernhard; Humayun, Munir

2016-10-01

Northwest Africa (NWA) 7034 and paired stones represent unique samples of martian polymict regolith breccia. Multiple breccia subsamples characterized in this work confirm highly siderophile element (HSE: Re, Os, Ir, Ru, Pt, Pd) contents that are consistently elevated (e.g., Os ∼9.3-18.4 ppb) above indigenous martian igneous rocks (mostly <5 ppb Os), equivalent to ∼3 wt% of admixed CI-type carbonaceous chondritic material, and occur in broadly chondrite-relative proportions. However, a protracted history of impactor component (metal and sulfide) breakdown and redistribution of the associated HSE has masked the original nature of the admixed meteorite signatures. The present-day 187Os/188Os ratios of 0.119-0.136 record a wider variation than observed for all major chondrite types. Combined with the measured 187Re/188Os ratios of 0.154-0.994, the range in Os isotope ratios indicates redistribution of Re and Os from originally chondritic components early in the history of the regolith commencing at ∼4.4 Ga. Superimposed recent Re mobility reflects exposure and weathering at or near the martian and terrestrial surfaces. Elevated Os concentrations (38.0 and 92.6 ppb Os), superchondritic Os/HSE ratios, and 187Os/188Os of 0.1171 and 0.1197 measured for two subsamples of the breccia suggest the redistribution of impactor material at ∼1.5-1.9 Ga, possibly overlapping with a (partial) resetting event at ∼1.4 Ga recorded by U-Pb isotope systematics in the breccia. Martian alteration of the originally chondritic HSE host phases, to form Os-Ir-rich nuggets and Ni-rich pyrite, implies the influence of potentially impact-driven hydrothermal systems. Multiple generations of impactor component admixture, redistribution, and alteration mark the formation and evolution of the martian regolith clasts and matrix of NWA 7034 and paired meteorites, from the pre-Noachian until impact ejection to Earth.

Characteristics of Martian Crustal Materials and Implications for Magmatic Assimilation: Preliminary Re-Os Isotope and Highly Siderophile Element Abundance Data for Nakhlites and Tissint

NASA Astrophysics Data System (ADS)

Mari, N.; Riches, A. J. V.; Hallis, L. J.; Lee, M. R.

2017-07-01

This project, for the first time, aims to integrate nakhlite Os-isotope compositions and HSE abundance data with S-isotope compositions for sample fractions for which textural information is constrained prior to destructive analyses.

Low Abundances of Highly Siderophile Elements in the Lunar Mantle: Evidence for Prolonged Late Accretion

NASA Technical Reports Server (NTRS)

Walker, R. J.; Horan, M. F.; Shearer, C. K.; Papike, J. J.

2004-01-01

The highly siderophile elements (HSE: including Re, Au, Ir, Os, Ru, Pt, Pd, Rh) are strongly partitioned into metal relative to silicates. In the terrestrial planets these elements are concentrated in metallic cores. Earth s mantle has sufficiently high abundances of the HSE (0.008 times CI abundances) that it has been hypothesized approximately 0.1-0.5% of the mass of the Earth was added following the last major interaction between the core and mantle [e.g. 1]. The additional material added to the Earth and Moon has been termed a late veneer , and the process has often been termed late accretion [2]. The timing of the dominant late accretionary period of the Earth and Moon is still poorly known. The abundances of HSE in the lunar mantle could provide important constraints on when the late veneer was added. The material that ultimately became the silicate portion of the Moon was likely stripped of most of its HSE prior to and during coalescence of the Moon. Consequently the initial lunar mantle likely had very low concentrations of the HSE. Unlike Earth, the generation of permanent lunar crust by 4.4 Ga prevented subsequent additions of HSE to the lunar mantle via continued accretion. Thus, if a substantial portion of the late veneer was added after 4.4 Ga, the lunar mantle should have retained very low HSE concentrations. Conversely, if the late veneer was mostly added prior to 4.4 Ga, HSE abundances in the lunar mantle may be roughly similar to abundances in the terrestrial mantle.

Formation of Apollo 16 impactites and the composition of late accreted material: Constraints from Os isotopes, highly siderophile elements and sulfur abundances

NASA Astrophysics Data System (ADS)

Gleißner, Philipp; Becker, Harry

2017-03-01

Fe-Ni metal-schreibersite-troilite intergrowths in Apollo 16 impact melt rocks and new highly siderophile element (HSE) and S abundance data indicate that millimeter-scale closed-system fractional crystallization processes during cooling of impactor-derived metal melt droplets in impact-melts are the main reason for compositional variations and strong differences in abundances and ratios of HSE in multiple aliquots from Apollo 16 impact melt rocks. Element ratios obtained from linear regression of such data are therefore prone to error, but weighted averages take into account full element budgets in the samples and thus represent a more accurate estimate of their impactor contributions. Modeling of solid metal-liquid metal partitioning in the Fe-Ni-S-P system and HSE patterns in impactites from different landing sites suggest that bulk compositions of ancient lunar impactites should be representative of impact melt compositions and that large-scale fractionation of the HSE by in situ segregation of solid metal or sulfide liquid in impact melt sheets most likely did not occur. The compositional record of lunar impactites indicates accretion of variable amounts of chondritic and non-chondritic impactor material and the mixing of these components during remelting of earlier ejecta deposits. The non-chondritic composition appears most prominently in some Apollo 16 impactites and is characterized by suprachondritic HSE/Ir ratios which increase from refractory to moderately volatile HSE and exhibit a characteristic enrichment of Ru relative to Pt. Large-scale fractional crystallization of solid metal from sulfur and phosphorous rich metallic melt with high P/S in planetesimal or embryo cores is currently the most likely process that may have produced these compositions. Similar materials or processes may have contributed to the HSE signature of the bulk silicate Earth (BSE).

Re-Os Systematics and HSE Distribution in Metal from Ochansk (H4) Chondrite

NASA Technical Reports Server (NTRS)

Smoliar, M. I.; Horan, M. F.; Alexander, C. M. OD.; Walker, R. J.

2003-01-01

Previous studies of the Re-Os systematics of chondrites have documented considerable variation in the Re/Os ratios of whole rock samples. For some whole rock chondrites, Re-Os systematics display large deviations from the primitive isochron that are considerably larger than deviations in other isotope systems. Possible interpretation of these facts is that the Re-Os system in chondrites is particularly sensitive to post-formation alteration processes, thus providing a useful tool to examine such processes. Significant variations that have been detected in highly siderophile element (HSE) patterns for ordinary chondrites support this conclusion. We report Re-Os isotope data for metal separates from the Ochansk H4 chondrite coupled with abundance data for Ru, Pd, Ir, and Pt, determined in the same samples by isotope dilution. We chose this meteorite mainly because it is an observed fall with minimal signs of weathering, and its low metamorphic grade (H4) and shock stage (S3).

Osmium isotopic homogeneity in the CK carbonaceous chondrites

NASA Astrophysics Data System (ADS)

Goderis, Steven; Brandon, Alan D.; Mayer, Bernhard; Humayun, Munir

2017-11-01

Variable proportions of isotopically diverse presolar components are known to account for nucleosynthetic isotopic anomalies for a variety of elements (e.g., Ca, Ti, Cr, Ni, Sr, Zr, Mo, Ru, Pd, Ba, Nd, and Sm) in both bulk chondrites and achondrites. However, although large Os isotopic anomalies have been measured in acid leachates and residues of unequilibrated chondrites, bulk chondrites of various groups, iron meteorites, and pallasites exhibit Os isotopic compositions that are indistinguishable from terrestrial or bulk solar isotopic abundances. Since the magnitude of nucleosynthetic anomalies is typically largest in the carbonaceous chondrites, this study reports high-precision Os isotopic compositions and highly siderophile element (HSE) concentrations for ten CK chondrites. The isotope dilution concentration data for HSE and high-precision Os isotope ratios were determined on the same digestion aliquots, to precisely correct for radiogenic contributions to 186Os and 187Os. While acid leached bulk unequilibrated carbonaceous chondrites show deficits of s-process Os components to the same extent as revealed by unequilibrated enstatite, ordinary, and Rumuruti chondrites, equilibrated bulk CK chondrites exhibit no resolvable Os isotopic anomalies. These observations support the idea that acid-resistant, carbon-rich presolar grains, such as silicon carbide (SiC) or graphite, are major carriers for nucleosynthetic isotopic anomalies of Os. The destruction of these presolar grains, which are omnipresent in unequilibrated meteorites, must have occurred during aqueous alteration and thermal metamorphism, early in the CK chondrite parent body history. The dispersal of CK chondrites along the IIIAB iron meteorite isochron on a 187Os/188Os versus 187Re/188Os diagram, with Re/Os ratios from 0.032 to 0.083, in combination with the observed redistribution of other HSE (e.g., Pt, Pd), highlights the influence of parent body processes, overprinted by effects of recent terrestrial alteration. Under the oxidizing conditions prevalent on the CK parent body, evident from high abundances of magnetite and limited Fe-Ni metal in CK chondrites, these parent body processes made all isotopically anomalous Os, originally hosted in reduced presolar grains, accessible. The absence of Os isotopic anomalies in ordinary, enstatite, and now also carbonaceous chondrites, implies that the carriers of s- and r-process Os must have been effectively homogenized across the region of chondrite formation, and possibly even the entire solar protoplanetary nebula, as suggested by the Os isotopic compositions of iron meteorites and non-anomalous ureilites. Except for a limited number of ureilites, the relative proportions of presolar s- and r-process carriers of Os (and other elements such as W) in chondrites, and most other planetary bodies, must have remained constant during all subsequent nebular and planetary processes, which appears not to have been the case for other siderophile elements, including Mo, Ru, and Pd. The existence of Mo, Ru, Pd and other siderophile element isotopic anomalies thus appears to be in part controlled by the chemical properties of these elements (e.g., volatility), their host phase(s) (e.g., SiC, graphite, metal, sulfides), and the nature of the nebular or planetary processes experienced in the early solar system.

Causes and extent of subduction-related highly siderophile element processing in oceanic mantle

NASA Astrophysics Data System (ADS)

O Driscoll, B.; Walker, R. J.; Day, J. M.; Daly, J. S.; Ash, R. D.

2013-12-01

Oceanic mantle samples that are accessible for study (e.g., abyssal and ophiolite peridotites) are commonly viewed as having undergone melt extraction at mid-ocean ridges (MOR). However, many ophiolite peridotites have been subjected to comparatively higher degrees of partial melting in supra-subduction zone (SSZ) environments too[1]. The ~497 Ma Leka Ophiolite, Norway, offers an ideal location for assessing the extent to which SSZ melting processes overprint the residual signatures of prior melt extraction. It comprises ~15 km[2] of well-exposed mantle and lower crustal peridotites that exhibit relatively limited serpentinisation. Extensive lithological heterogeneity is evident within the harzburgitic host rock, in the form of lenses and sheets of dunite, pyroxenite and chromitite. These have been interpreted as representing successive generations of SSZ-related channelised upper mantle melt migration and melt-rock interaction[2]. The integrated application of highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, Re) abundances and 187Os/188Os measurements of oceanic mantle peridotite has proved valuable in assessing the timing of mantle melting processes occurring within the upper mantle, as well as the scales of upper mantle heterogeneity[3,4]. At 497 Ma, the Os isotopic compositions of Leka harzburgites averaged ~2% more radiogenic than the projected average for abyssal peridotites[4] at that time. Several of the harzburgites are characterised by low initial 187Os/188Os (as low as 0.1202), interpreted as reflecting Proterozoic melt depletion, a common characteristic of melt-depleted peridotites comprising most ophiolites. Dunites, pyroxenites and chromitites show considerably more variable initial 187Os/188Os and HSE abundances; some pyroxenites have extreme Pt abundances (to 1-2 ppm), supra-chondritic Pt/Os and 187Os/188Os, yet some of the dunites are also characterised by 187Os/188Os well within the range of the harzburgites. A number of dunites have relatively radiogenic initial 187Os/188Os (up to 0.1385), suggesting that they either formed from selectively more radiogenic melt or that their development predates that of the ophiolite by ~500 Ma. Assuming that the significant lithological heterogeneity observed in the Leka upper mantle section was generated during SSZ melting, it appears that consequent modification of the HSE compositions and 187Os/188Os was restricted to pyroxenites and some, but perhaps not all, of the dunites. Mineral scale observations, coupled with a comparison of the Leka data and those from the ~492 Ma Shetland Ophiolite (Scotland)[3], suggest that sulphide/arsenide mobilisation during channelised melt-rock interactions is the trigger for fractionation of the HSE and modification of 187Os/188Os in ophiolite dunites. [1] Dilek and Furnes (2011) GSA Bulletin 123(3/4), 387-411 [2] Maaløe (2005) Mineralogy and Petrology 85, 163-204 [3] O'Driscoll et al. (2012) EPSL 333-334, 226-237 [4] Liu et al. (2009) EPSL 283, 122-132

Highly Siderophile Elements, 187Re-187 Os and 182Hf-182W Isotopic Systematics of Early Solar System Materials: Constraining the Early Evolution of Chondritic and Achondritic Parent Bodies

NASA Astrophysics Data System (ADS)

Archer, Gregory J.

Highly siderophile element (HSE) abundances and 187Re- 187Os isotopic systematics for H chondrites and ungrouped achondrites, as well as 182Hf-182W isotopic systematics of H and CR chondrites are reported. Achondrite fractions with higher HSE abundances show little disturbance of 187Re-187Os isotopic systematics. By contrast, isotopic systematics for lower abundance fractions are consistent with minor Re mobilization. For magnetically separated H chondrite fractions, the magnitudes of disturbance for the 187Re-187Os isotopic system follow the trend coarse-metal isotopic system follow the trend coarse-metal

186Os-187Os and highly siderophile element abundance systematics of the mantle revealed by abyssal peridotites and Os-rich alloys

NASA Astrophysics Data System (ADS)

Day, James M. D.; Walker, Richard J.; Warren, Jessica M.

2017-03-01

Abyssal peridotites are oceanic mantle fragments that were recently processed through ridges and represent residues of both modern and ancient melting. To constrain the nature and timing of melt depletion processes, and the composition of the mantle, we report high-precision Os isotope data for abyssal peridotites from three ocean basins, as well as for Os-rich alloys, primarily from Mesozoic ophiolites. These data are complemented by whole-rock highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, Re), trace- and major-element abundances for the abyssal peridotites, which are from the Southwest Indian (SWIR), Central Indian (CIR), Mid-Atlantic (MAR) and Gakkel Ridges. The results reveal a limited role for melt refertilization or secondary alteration processes in modifying abyssal peridotite HSE compositions. The abyssal peridotites examined have experienced variable melt depletion (2% to >16%), which occurred >0.5 Ga ago for some samples. Abyssal peridotites typically exhibit low Pd/Ir and, combined with high-degrees of estimated total melt extraction, imply that they were relatively refractory residues prior to incorporation into their present ridge setting. Recent partial melting processes and mid-ocean ridge basalt (MORB) generation therefore played a limited role in the chemical evolution of their precursor mantle domains. The results confirm that many abyssal peridotites are not simple residues of recent MORB source melting, having a more complex and long-lived depletion history. Peridotites from the Gakkel Ridge, SWIR, CIR and MAR indicate that the depleted MORB mantle has 186Os/188Os of 0.1198356 ± 21 (2SD). The Phanerozoic Os-rich alloys yield an average 186Os/188Os within uncertainty of abyssal peridotites (0.1198361 ± 20). Melt depletion trends defined between Os isotopes and melt extraction indices (e.g., Al2O3) allow an estimate of the primitive mantle (PM) composition, using only abyssal peridotites. This yields 187Os/188Os (0.1292 ± 25), and 186Os/188Os of 0.1198388 ± 29, both of which are within uncertainty of previous primitive mantle estimates. The 186Os/188Os composition of the PM is less radiogenic than for some plume-related lavas, with the latter requiring sources with high long-term time-integrated Pt/Os. Estimates of primitive mantle HSE concentrations using abyssal peridotites define chondritic Pd/Ir, which differs from previous supra-chondritic estimates for Pd/Ir based on peridotites from a range of tectonic settings. By contrast, estimates of PM yield supra-chondritic Ru/Ir. The cause of enhanced Ru in the mantle remains enigmatic, but may reflect variable partitioning behavior of Ru at high pressure and temperature.

Re-187-Os-187, Pt-190-Os-186 Isotopic and Highly Siderophile Element Systematics of Group IVA Irons

NASA Technical Reports Server (NTRS)

Walker, R. J.; McCoy, T. J.; Schulte, R. F.; McDonough, W. F.; Ash, R. D.

2005-01-01

We have recently completed Re-187-Os-187 and Pt-190-Os-186 isotopic and elemental studies of the two largest magmatic iron meteorite groups, IIAB and IIIAB [1]. These studies revealed closed-system behavior of both isotopic systems, but complex trace element behavior for Re, Pt and Os in group IIIAB. Here we examine isotopic and trace elemental systematics of group IVA irons. The IVA irons are not as extensively fractionated as IIAB and IIIAB and their apparently less complex crystallization history may make for more robust interpretation of the relative partitioning behavior of Re, Pt and Os, as well as the other highly siderophile elements (HSE) measured here; Pd, Ru and Ir [e.g. 2]. An additional goal of our continuing research plan for iron meteorites is to assess the possibility of relating certain ungrouped irons with major groups via trace element modeling. Here, the isotopic and trace element systematics of the ungrouped irons Nedagolla and EET 83230 are compared with the IVA irons.

Length-scales of chemical and isotopic heterogeneity in the mantle section of the Shetland Ophiolite Complex, Scotland

NASA Astrophysics Data System (ADS)

O'Driscoll, B.; Walker, R. J.; Clay, P. L.; Day, J. M. D.; Ash, R. D.; Daly, J. S.

2018-04-01

Kilometre to sub-metre scale heterogeneities have been inferred in the oceanic mantle based on sampling of both ophiolites and abyssal peridotites. The ∼492 Ma Shetland Ophiolite Complex (SOC) contains a well-preserved mantle section that is dominated by harzburgite (∼70 vol.%) previously reported to have variable major and trace element compositions, yet dominantly chondritic initial 187Os/188Os compositions. To assess the preservation of compositional heterogeneities at sub-metre length-scales in the oceanic mantle, a ∼45 m2 area of the SOC mantle section was mapped and sampled in detail. Harzburgites, dunites and a pyroxenite from this area were analysed for lithophile and highly-siderophile element (HSE) abundances, as well as for 187Os/188Os ratios. Lithophile element data for most rocks are characteristic of supra-subduction zone (SSZ) metasomatic processes. Two dunites have moderately fractionated HSE patterns and suprachondritic γOs(492 Ma) values (+5.1 and +7.5) that are also typical of ophiolitic dunites generated by SSZ melt-rock interactions. By contrast, six harzburgites and four dunites have approximately chondritic-relative abundances of Os, Ir and Ru, and γOs(492 Ma) values ranging only from -0.6 to +2.7; characteristics that imply no significant influence during SSZ processes. Two harzburgites are also characterised by significantly less radiogenic γOs(492 Ma) values (-3.5 and -4), and yield Mesoproterozoic time of Re depletion (TRD) model ages. The range of Os isotope compositions in the studied area is comparable to the range reported for a suite of samples representative of the entire SOC mantle section, and approaches the total isotopic variation of the oceanic mantle, as observed in abyssal peridotites. Mechanisms by which this heterogeneity can be formed and preserved involve inefficient and temporally distinct melt extraction events and strong localised channelling of these melts.

Target rocks, impact glasses, and melt rocks from the Lonar crater, India: Highly siderophile element systematics and Sr-Nd-Os isotopic signatures

NASA Astrophysics Data System (ADS)

Schulz, Toni; Luguet, Ambre; Wegner, Wencke; Acken, David; Koeberl, Christian

2016-07-01

The Lonar crater is a ~0.57-Myr-old impact structure located in the Deccan Traps of the Indian peninsula. It probably represents the best-preserved impact structure hosted in continental flood basalts, providing unique opportunities to study processes of impact cratering in basaltic targets. Here we present highly siderophile element (HSE) abundances and Sr-Nd and Os isotope data for target basalts and impactites (impact glasses and impact melt rocks) from the Lonar area. These tools may enable us to better constrain the interplay of a variety of impact-related processes such as mixing, volatilization, and contamination. Strontium and Nd isotopic compositions of impactites confirm and extend earlier suggestions about the incorporation of ancient basement rocks in Lonar impactites. In the Re-Os isochron plot, target basalts exhibit considerable scatter around a 65.6 Myr Re-Os reference isochron, most likely reflecting weathering and/or magma replenishment processes. Most impactites plot at distinctly lower 187Re/188Os and 187Os/188Os ratios compared to the target rocks and exhibit up to two orders of magnitude higher abundances of Ir, Os, and Ru. Moreover, the impactites show near-chondritic interelement ratios of HSE. We interpret our results in terms of an addition of up to 0.03% of a chondritc component to most impact glasses and impact melt rocks. The magnitude of the admixture is significantly lower than the earlier reported 12-20 wt% of extraterrestrial component for Lonar impact spherules, reflecting the typical difference in the distribution of projectile component between impact glass spherules and bulk impactites.

Late Chondritic Additions and Planet and Planetesimal Growth: Evaluation of Physical and Chemical Mechanisms

NASA Technical Reports Server (NTRS)

Righter, Kevin

2013-01-01

Studies of terrestrial peridotite and martian and achondritic meteorites have led to the conclusion that addition of chondritic material to growing planets or planetesimals, after core formation, occurred on Earth, Mars, asteroid 4 Vesta, and the parent body of the angritic meteorites [1-4]. One study even proposed that this was a common process in the final stages of growth [5]. These conclusions are based almost entirely on the highly siderophile elements (HSE; Re, Au, Pt, Pd, Rh, Ru, Ir, Os). The HSE are a group of eight elements that have been used to argue for late accretion of chondritic material to the Earth after core formation was complete (e.g., [6]). This idea was originally proposed because the D(metal/silicate) values for the HSE are so high, yet their concentration in the mantle is too high to be consistent with such high Ds. The HSE also are present in chondritic relative abundances and hence require similar Ds if this is the result of core-mantle equilibration. Since the work of [6] there has been a realization that core formation at high PT conditions can explain the abundances of many siderophile elements in the mantle (e.g., [7]), but such detailed high PT partitioning data are lacking for many of the HSE to evaluate whether such ideas are viable for all four bodies. Consideration of other chemical parameters reveals larger problems that are difficult to overcome, but must be addressed in any scenario which calls on the addition of chondritic material to a reduced mantle. Yet these problems are rarely discussed or emphasized, making the late chondritic (or late veneer) addition hypothesis suspect.

Nanoscale variations in 187Os isotopic composition and HSE systematics in a Bultfontein peridotite

NASA Astrophysics Data System (ADS)

Wainwright, A. N.; Luguet, A.; Schreiber, A.; Fonseca, R. O. C.; Nowell, G. M.; Lorand, J.-P.; Wirth, R.; Janney, P. E.

2016-08-01

Understanding the mineralogical controls on radiogenic chronometers is a fundamental aspect of all geochronological tools. As with other common dating tools, it has become increasingly clear that the Re-Os system can be impacted by multiple mineral formation events. The accessory and micrometric nature of the Re-Os-bearing minerals has made assessing this influence complex. This is especially evident in cratonic peridotites, where long residence times and multiple metasomatic events have created a complex melting and re-enrichment history. Here we investigate a harzburgitic peridotite from the Bultfontein kimberlite (South Africa) which contains sub-micron Pt-Fe-alloy inclusions within base metal sulphides (BMS). Through the combination of the focused ion beam lift-out technique and low blank mass spectrometry we were able to remove and analyse the Pt-Fe-alloy inclusions for their Re-Os composition and highly siderophile element (HSE) systematics. Six repeats of the whole-rock yield 187Os/188Os compositions of 0.10893-0.10965, which correspond to Re depletion model ages (TRD) of 2.69-2.79 Ga. The Os, Ir and Pt concentrations are slightly variable across the different digestions, whilst Pd and Re remain constant. The resulting HSE pattern is typical of cratonic peridotites displaying depleted Pt and Pd. The Pt-Fe-alloys have PUM-like 187Os/188Os compositions of 0.1294 ± 24 (2-s.d.) and 0.1342 ± 38, and exhibit a saw-tooth HSE pattern with enriched Re and Pt. In contrast, their BMS hosts have unradiogenic 187Os/188Os of 0.1084 ± 6 and 0.1066 ± 3, with TRD ages of 2.86 and 3.09 Ga, similar to the whole-rock systematics. The metasomatic origin of the BMS is supported by (i) the highly depleted nature of the mantle peridotite and (ii) their Ni-rich sulphide assemblage. Occurrence of Pt-Fe-alloys as inclusions within BMS grains demonstrates the genetic link between the BMS and Pt-Fe-alloys and argues for formation during a single but continuous event of silicate melt percolation. While the high solubility of HSE within sulphide mattes rules out early formation of the alloys from a S-undersaturated silicate melt and subsequent scavenging in a sulphide matte, the alignment of the Pt-Fe-alloy inclusions attests that they are exsolutions formed during the sub-solidus re-equilibration of the high temperature sulphide phases. The significant difference in 187Os/188Os composition between the included Pt-Fe-alloys and their BMS host can only be accounted for by different Re/Os. This suggests that the formation of Pt-Fe-alloy inclusions within a BMS can result in the fractionation of Re from Os. A survey experiment examining the partitioning of Re and Os confirmed this observation, with the Re/Os of the Pt-Fe-alloy inclusion up to ten times higher than the co-existing BMS. This fractionation implies that, when Re is present in the sulphide melt, the TRD ages of BMS containing alloy inclusions do not date the loss of Re due to partial melting, but rather its fractionation into the Pt-Fe-alloys. As such, BMS ages should be used with caution when dating ancient partial melting events.

Re-Os Isotopic Constraints on the Chemical Evolution and Differentiation of the Martian Mantle

NASA Technical Reports Server (NTRS)

Brandon, Alan D.; Walker, Richard J.

2002-01-01

The (187)Re-187Os isotopic systematics of SNC meteorites, thought to be from Mars, provide valuable information regarding the chemical processes that affected the Martian mantle, particularly with regard to the relative abundances of highly siderophile elements (HSE). Previously published data (Birck and Allegre 1994, Brandon et al. 2000), and new data obtained since these studies, indicate that the HSE and Os isotopic composition of the Martian mantle was primarily set in its earliest differentiation history. If so, then these meteorites provide key constraints on the processes that lead to variation in HSE observed in not only Mars, but also Earth, the Moon and other rocky bodies in the Solar System. Processes that likely have an effect on the HSE budgets of terrestrial mantles include core formation, magma ocean crystallization, development of juvenile crust, and the addition of a late veneer. Each of these processes will result in different HSE variation and the isotopic composition of mantle materials and mantle derived lavas. Two observations on the SNC data to present provide a framework for which to test the importance of each of these processes. First, the concentrations of Re and Os in SNC meteorites indicate that they are derived from a mantle that has similar concentrations to the Earth's mantle. Such an observation is consistent with a model where a chondritic late veneer replenished the Earth and Martian mantles subsequent to core formation on each planet. Alternative models to explain this observation do exist, but will require additional data to test the limitations of each. Second, Re-Os isotopic results from Brandon et al. (2000) and new data presented here, show that initial yos correlates with variations in the short-lived systems of (182)Hf- (182)W and (142)Sm-142Nd in the SNC meteorites (epsilon(sub W) and epsilon(sub 142Nd)). These systematics require an isolation of mantle reservoirs during the earliest differentiation history of Mars, and subsequent inefficient mixing between these reservoirs. These data show that models for the origin of isotopic variation for SNC meteorites require at least two long-lived mantle reservoirs, and possibly three. The range in the projected present day gamma(sub Os) of these reservoirs is from -5.4+/-2.6, to +4+/-1. The isotopic systematics of these reservoirs may be linked to development of cumulate crystal piles in a Martian magma ocean and variable amounts of late stage intercumulus melt. In this model, fractional crystallization of olivine and possibly other phases with slightly subchondritic Re/Os, from a solidifying magma ocean, resulted in a lower Re/Os ratio early cumulates, and a resultant low gamma(sub Os). Later cumulates or evolved melts crystallized with higher Re/Os ratios to produce the mantle reservoir(s) with consequent higher gamma(sub Os). Crystallization of the Martian magma ocean followed earliest core formation, as indicated by the correlation of epsilon(sub W) with epsilon(sub 142Nd) and initial gamma(sub Os).

Effect of Silicon on the Activity Coefficient of Rhenium in Fe-Si Liquids: Implications for HSE and Os Isotopes in Planetary Mantles

NASA Technical Reports Server (NTRS)

Righter, K.; Pando, K.; Yang, S.; Humayun, M.

2018-01-01

Metallic cores contain light alloying elements that can be a combination of S, C, Si, and O, all of which have important chemical and physical influences. For Earth, Si may be the most abundant light element in the core. Si dissolved into Fe liquids can have a large effect on the magnitude of the activity coefficient of siderophile elements (SE), and thus the partitioning behavior of those elements between core and mantle. The effect of Si on the highly siderophile elements is only beginning to be studied and the effects on Au, Pd and Pt are significant. Here we report new experiments designed to quantify the effect of Si on the partitioning of Re between metal and silicate melt. A solid understanding of Re partitioning is required for a complete understanding of the Re-Os isotopic systems. The results will be applied to understanding the HSEs and Os isotopic data for planetary mantles, and especially Earth.

Atmospheric outgassing and native-iron formation during carbonaceous sediment-basalt melt interactions

NASA Astrophysics Data System (ADS)

Pernet-Fisher, John F.; Day, James M. D.; Howarth, Geoffrey H.; Ryabov, Victor V.; Taylor, Lawrence A.

2017-02-01

Organic carbon-rich sediment assimilation by basaltic magmas leads to enhanced emission of greenhouse gases during continental flood basalt eruptions. A collateral effect of these interactions is the generation of low oxygen fugacities (fO2) (below the iron-wüstite [IW] buffer curve) during magmatic crystallization, resulting in the precipitation of native-iron. The occurrence of native-iron bearing terrestrial basaltic rocks are rare, having been identified at three locations: Siberia, West Greenland, and Central Germany. We report the first combined study of Re-Os isotopes, highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, Re), and trace-element abundances for these three occurrences, in addition to host sediments at West Greenland. To quantify the amount of crustal assimilation experienced by the magmas, we present combined crystallization and assimilation models, together with fractional crystallization models, to assess how relative abundances of the HSE have been modified during crystallization. The radiogenic osmium isotopic compositions (γOsinitial +15 to +193) of mafic igneous samples are consistent with assimilation of old high Re/Os crustal contaminants with radiogenic 187Os/188Os, whereas the HSE inter-element fractionations (Pd/Os 2 to >10,000) suggest that some Siberian samples underwent an early stage of sulfide removal. Metalliferous samples from the Siberian intrusions of Khungtukun and Dzhaltul (associated with the Siberian flood basalts) yield internal 187Re-187Os ages of 266 ± 83Ma and 249 ± 50Ma, respectively, reflecting late-Permian emplacement ages. These results imply that crustal assimilation took place prior to crystallization of native-Fe. In contrast, metalliferous samples from Disko Island and Bühl (associated with the West Greenland flood basalts, and the Central European Volcanic Province, respectively) have trends in 187Re/188Os-187Os/188Os space corresponding to apparent ages older than their reported crystallization ages. These anomalous ages probably reflect concurrent assimilation of high Re/Os, radiogenic 187Os crust during crystallization of native-Fe, consistent with the character of local West Greenland sediments. In all three locations, calculations of combined assimilation of crustal sediments and fractional crystallization indicate between 1-7% assimilation can account for the Os-isotope systematics. In the case of Siberian samples, incompatible trace-element abundances indicate that lower crustal assimilation may have also occurred, consistent with the suggestion that crustal assimilation took place prior to native-Fe precipitation. The extent of local crustal contamination at Siberia, West Greenland, and Bühl necessitates that significant quantities of CH4, CO, CO2, SO2 and H2 O were released during assimilation of carbonaceous sediments. Consequently, carbonaceous sediment-basalt melt interactions have collateral effects on total gas output from flood basalt volcanism into the atmosphere. However, the amount of carbonaceous sediment contamination experienced by melts forming the Khungtukun and Dzhaltul intrusions alone, cannot explain the major C-isotope excursions at the Permo-Triassic mass-extinction event. Instead, further unsampled intrusions that also experienced significant carbonaceous sediment-melt interactions would be required. Enhanced greenhouse gas-emission during the Permo-Triassic mass extinction may have been facilitated by a combination of mantle melting and carbonaceous sediment-melt interactions, together with other proposed mechanisms, including wildfires, or by microbial metabolic exhalation.

Os and HSE of the hot upper mantle beneath southern Tibet: Indian mantle affinity?

NASA Astrophysics Data System (ADS)

Zhao, Z.; Dale, C. W.; Pearson, D. G.; Niu, Y.; Zhu, D.; Mo, X.

2011-12-01

The subduction of the Indian plate (including cratonic continental crust and/or upper mantle) beneath southern Tibet is widely accepted from both geological and geophysical studies. Mantle-derived xenoliths from this region provide a means of directly investigating the mantle underlying the southern part of the plateau. Studies of xenoliths hosted in the Sailipu ultrapotassic volcanic rocks, erupted at ~17 Ma, have indicated that the subcontinental mantle of southern Tibetan Plateau is hot and strongly influenced by metasomatism (Zhao et al., 2008a, b; Liu et al., 2011). Here we report comprehensive EPMA and LA-ICP-MS major and trace element data for the Sailipu xenoliths and also whole rock Os isotope and HSE data in order to constrain the depletion history of the mantle and to identify the presence of any potential Indian cratonic mantle. The xenoliths, ranging in size from 0.5cm to 1.5cm in diameter, are mostly peridotites. The calculated temperatures are 1010-1230°C at the given pressures of ~1.6-2.0 GPa (n=47). These P-T conditions are similar to rift-related upper mantle regimes (e.g. Kenya), indicating the influence of regional extension beneath southern Tibet in the Miocene. A series of compositional discriminations for minerals (Cpx, Opx, Ol, and Phl), e.g. Fo<90, suggest that the xenoliths are non-cratonic spinel-peridotite (cratonic peridotite olivine Fo> ~91), with a clear metasomatic signature We obtained Os isotope data and abundances of highly siderophile elements (HSE, including Os, Ir, Ru, Pt, Pd and Re) on a set of six olivine-dominated peridotite samples from Sailipu volcanics, less than 1 cm in dimension. They allow us to further constrain the nature and state of the upper mantle beneath the southern Tibet. Sailipu samples display low total HSE abundances (Os+Ir+Ru+Pt+Pd+Re) ranging from 8.7 to 25 ppb, with nearly constant Os, Ir , and Ru, but rather varied Pt (2-13), Pd (0.4-5.2), and Re (0.01-0.5). Chondrite-normalised Pd/Ir ratios range from 0.2 to 2.4 reflecting significant metasomatism of some samples. The xenoliths exhibit 187Os/188Os ratios of 0.12213-0.12696, corresponding to γOs ranging from -4.2 to -0.4 - much higher than ancient cratonic mantle. Thus, on the basis of mineral chemistry and whole rock Os isotopes, Indian cratonic mantle is absent from our suite of xenoliths. Therefore, assuming the presence of cratonic mantle, it seems likely that the xenoliths do not sample the deep basal section of the lithosphere where cratonic Indian lithosphere is thought to be present under southern Tibet. In which case, testing of the seismic and tectonic models may not be possible without garnet-facies peridotites. More work need to be done to further reveal the mantle compostion and mantle dynamics beneath Tibet. [Financially supported by the National Key Project for Basic Research of China (Project 2011CB403102 and 2009CB421002)]. [1] Zhao Z, et al., 2008a. Acta Petrologica Sinica, 24 (2): 193-202 [2] Zhao Z, et al., 2008b. Geochimica et Cosmochimica Acta, 72, 12 (Supp.): A1095 [3] Liu C-Z, et al., 2011, Geology, in press

Ophiolite Perspectives on Oceanic Mantle Heterogeneity

NASA Astrophysics Data System (ADS)

Walker, R. J.; O'Driscoll, B.; Day, J. M.; Ash, R. D.; Daly, J. S.

2014-12-01

The mantle sections of ophiolites offer a useful approach to studying compositional heterogeneities in the oceanic mantle. A potential caveat is that the tectonic provenance of ophiolites is often not easy to decipher, although many have undergone at least supra-subduction zone (SSZ) processing. Significant outstanding questions include the degree to which ophiolite peridotites preserve evidence of pre-SSZ events and the way that SSZ melt extraction modifies the character of these peridotites. A suite of Caledonian ophiolites associated with the closure of the Iapetus Ocean offers an opportunity to shed light on these issues, in particular to assess the degree to which long (regional) wavelength compositional heterogeneities survive SSZ melting. Observations on the combined highly-siderophile element (HSE) and 187Os/188Os systematics of the broadly coetaneous (490-500 Ma) Shetland Ophiolite Complex (Scotland) and Leka Ophiolite Complex (LOC; Norway) are presented here. Generally, the lithological composition of each locality is harzburgitic, and hosts lenses and layers of dunite, chromitite and pyroxenite that are interpreted as representing SSZ-related (channelised) melt migration and melt-rock interaction. Although the bulk of the harzburgitic rocks have approximately chondritic initial 187Os/188Os and HSE abundances, ancient (Proterozoic) melt depletion (TRD =1.4 to 1 Ga) is recorded in ~10% of samples from each locality. This is also commonly observed in abyssal peridotites. One important implication of the data is that SSZ melt generation/migration has had no discernible impact on the bulk Os isotopic composition of the Iapetus oceanic mantle. By contrast, non-harzburgitic lithologies consistently exhibit more radiogenic initial 187Os/188Os and more variable HSE abundances. The dunites, chromitites and pyroxenites of the LOC can be separated into two groups on the basis of isochrons that they define; yielding ages of 481±22 Ma and 589±15 Ma, respectively. The former age corresponds, within error, to the accepted age of the ophiolite (497 ± 2 Ma). The meaning of the latter age is uncertain, but may correspond to the early stages of Iapetus opening. The data imply that the oceanic mantle represented by both ophiolites resembles a 'patchwork' of peridotites of different ages and compositions.

Re-Evaluation of HSE DATA in Light of High P-T Partitioning Data: Late Chondritic Addition to Inner Solar System Bodies Not Always Required for HSE

NASA Technical Reports Server (NTRS)

Righter, K.

2015-01-01

Studies of terrestrial peridotite and martian and achondritic meteorites have led to the conclusion that addition of chondritic material to growing planets or planetesimals, after core formation, occurred on Earth, Moon, Mars, asteroid 4 Vesta, and the parent body of the angritic meteorites. One study even proposed that this was a common process in the final stages of growth. These conclusions are based al-most entirely on the 8 highly siderophile elements (HSE; Re, Au, Pt, Pd, Rh, Ru, Ir, Os), which have been used to argue for late accretion of chondritic material to the Earth after core formation was complete. This idea was originally proposed because the D(metal/silicate) values for the HSE are very high (greater than 10,000), yet their concentration in the terrestrial mantle is too high to be consistent with such high Ds. The HSE in the terrestrial mantle also are present in chondritic relative abundances and hence require similar Ds if this was the result of core-mantle equilibration. The conclusion that late chondritic additions are required for all five of these bodies is based on the chondritic relative abundances of the HSE, as well as their elevated concentrations in the samples. An easy solution is to call upon addition of chondritic material to the mantle of each body, just after core formation; however, in practice this means similar additions of chondritic materials to each body just after core formation which ranges from approximately 4-5 Ma after T(sub 0) for 4 Vesta and the angrites, to 10-25 Ma for Mars, to 35 to 60 Ma for Moon and perhaps the Earth. Since the work of there has been a realization that high PT conditions can lower the partition coefficients of many siderophile elements, indicating that high PT conditions (magma ocean stage) can potentially explain elevated siderophile element abundances. However, detailed high PT partitioning data have been lacking for many of the HSE to evaluate whether such ideas are viable for all four bodies. Re-cent partitioning studies have covered P, T, fO2, and compositional ranges that allow values to be predicted at conditions relevant to these five inner solar system bodies. Because the D(HSE) metal/silicate are lowered substantially at higher PT conditions and natural com-positions (FeNi metallic liquids and peridotites) it is natural to re-examine the role of core formation on the HSE patterns in a variety of inner solar system bodies. Here I will discuss other processes (including high PT core formation for Mars, Moon and Earth) that can produce the observed HSE patterns, and demonstrate that there are viable hypotheses other than the "one size fits all" hypothesis of late chondritic additions.

Isotopic And Geochemical Investigations Of Meteorites

NASA Technical Reports Server (NTRS)

Walker, Richard J.

2005-01-01

The primary goals of our research over the past four years are to constrain the timing of certain early planetary accretion/differentiation events, and to constrain the proportions and provenance of materials involved in these processes. This work was achieved via the analysis and interpretation of long- and short-lived isotope systems, and the study of certain trace elements. Our research targeted these goals primarily via the application of the Re-187, Os-187, Pt-190 Os-186 Tc-98 Ru-99 and Tc-99 Ru-99 isotopic systems, and the determination/modeling of abundances of the highly siderophile elements (HSE; including Re, Os, Ir, Ru, Pd, Pt, and maybe Tc). The specific events we examined include the segregation and crystallization histories of asteroidal cores, the accretion and metamorphic histories of chondrites and chondrite components, and the accretionary and differentiation histories of Mars and the Moon.

Precious metal enrichment at low-redox in terrestrial native Fe-bearing basalts investigated using laser-ablation ICP-MS

NASA Astrophysics Data System (ADS)

Howarth, Geoffrey H.; Day, James M. D.; Pernet-Fisher, John F.; Goodrich, Cyrena A.; Pearson, D. Graham; Luo, Yan; Ryabov, Viktor V.; Taylor, Lawrence A.

2017-04-01

Primary native Fe is a rare crystallizing phase from terrestrial basaltic magmas, requiring highly reducing conditions (fO2

A carbon-rich region in Miller Range 091004 and implications for ureilite petrogenesis

NASA Astrophysics Data System (ADS)

Day, James M. D.; Corder, Christopher A.; Cartigny, Pierre; Steele, Andrew M.; Assayag, Nelly; Rumble, Douglas; Taylor, Lawrence A.

2017-02-01

Ureilite meteorites are partially melted asteroidal-peridotite residues, or more rarely, cumulates that can contain greater than three weight percent carbon. Here we describe an exceptional C-rich lithology, composed of 34 modal % large (up to 0.8 mm long) crystalline graphite grains, in the Antarctic ureilite meteorite Miller Range (MIL) 091004. This C-rich lithology is embedded within a silicate region composed dominantly of granular olivine with lesser quantities of low-Ca pyroxene, and minor FeNi metal, high-Ca pyroxene, spinel, schreibersite and troilite. Petrological evidence indicates that the graphite was added after formation of the silicate region and melt depletion. Associated with graphite is localized reduction of host olivine (Fo88-89) to nearly pure forsterite (Fo99), which is associated with FeNi metal grains containing up to 11 wt.% Si. The main silicate region is typical of ureilite composition, with highly siderophile element (HSE) abundances ∼0.3 × chondrite, 187Os/188Os of 0.1260-0.1262 and Δ17O of -0.81 ± 0.16‰. Mineral trace-element analyses reveal that the rare earth elements (REE) and the HSE are controlled by pyroxene and FeNi metal phases in the meteorite, respectively. Modeling of bulk-rock REE and HSE abundances indicates that the main silicate region experienced ∼6% silicate and >50% sulfide melt extraction, which is at the lower end of partial melt removal estimated for ureilites. Miller Range 091004 demonstrates heterogeneous distribution of carbon at centimeter scales and a limited range in Mg/(Mg + Fe) compositions of silicate grain cores, despite significant quantities of carbon. These observations demonstrate that silicate rim reduction was a rapid disequilibrium process, and came after silicate and sulfide melt removal in MIL 091004. The petrography and mineral chemistry of MIL 091004 is permissive of the graphite representing late-stage C-rich melt that pervaded silicates, or carbon that acted as a lubricant during anatexis and impact disruption in the parent body. Positive correlation of Pt/Os ratios with olivine core compositions, but a wide range of oxygen isotope compositions, indicates that ureilites formed from a compositionally heterogeneous parent body that experienced variable sulfide and metal melt-loss that is most pronounced in relatively oxidized ureilites with Δ17O between -1.5 and ∼0‰.

New insights from old spherules: Os-W isotope and HSE evidence for Paleoarchean meteorite bombardment of the Earth

NASA Astrophysics Data System (ADS)

Schulz, T.; Luguet, A. A.; Koeberl, C.

2014-12-01

Introduction: Although still debated, spherule beds in the Barberton Mountain Land (~3.4 Ga) are suspected to represent remnants of impact-generated and ballistically emplaced silicate melt droplets [e.g. 1]. Such deposits provide the only window into the late stages of the heavy meteorite bombardment on Earth as their source craters have long since been obliterated. In order to identify a possible meteoritic component and, if successful, to discuss potential projectile materials, we are performing a detailed Os-W isotope as well as HSE abundance study on spherule layers from the recently drilled ICDP BARB5 core (grid location 25°30`50.76``S, 31°33`10.08``E). Samples and Methods: Samples were taken from a spherule-containing meta-sedimentary core section discovered between 510 and 512 m depth. About 100 mg of homogenized sample powders were spiked with a mixed 190Os, 185Re, 191Ir and 194Pt tracer and treated in a high pressure asher using inverse aqua regia, followed by conventional extraction schemes for Os and the other HSEs [4]. Chemical and Os isotope measurements (via N-TIMS) were performed in Vienna, whereas HSE measurements were undertaken via ICP MS in Bonn. Results and Discussion: Our preliminary Os isotope data reveal a trend between samples exhibiting high spherule to matrix ratios (187Os/188Os ~0.106 and Os ~0.4 ppm) and samples with lower ones (187Os/188Os up to ~0.304 and Os ~0.008 ppm). Notably, the most unradiogenic samples exhibit carbonaceous-chondrite-like initial 187Os/188Os and HSE ratios, whereas all other samples are clear non-chondritic. These findings support an extraterrestrial contribution in the spherules and can be interpreted compared to conclusions drawn from a Cr isotope study performed on similar samples [3], possibly representing a different impact event and favouring a chondritic projectile. However, further considerations based on precise Os/W ratio determinations and high-precision 182W isotope data, will be presented at the conference. Acknowledgements:We thank W.U. Reimold and T. Mohr-Westheide (Natural History Museum Berlin) for the BARB5 samples, which were obtained in an ICDP project. References: [1] Simonson and Glass, 2004; [2] Lowe et al., 1989; [3] Kyte et al., 2003; [4] Cohen and Waters, 1996; [5] Morel et al., 2002

Re-187 Os-187 Isotopic and Highly Siderophile Element Systematics of Group IVB Irons

NASA Technical Reports Server (NTRS)

Honesto, J.; McDonough, W. F.; Walker, R. J.; McCoy, T. J.; Ash, R. D.

2005-01-01

Study of the magmatic iron meteorite groups permits constraints to be placed on the chemical and isotopic composition of parent bodies, and the timing of, and crystal-liquid fractionation processes involved in the crystallization of asteroidal cores. Here we examine Re-Os isotopic and trace elemental systematics of group IVB irons. Compared to most irons, the irons comprising this group are enriched in some of the most refractory siderophile elements, yet highly-depleted in most volatile siderophile elements. These characteristics have been attributed to processes such as high temperature condensation of precursor materials and oxidation in the parent body. Most recently it has been suggested that both processes may be involved in the chemical complexity of the group. Here, high precision isotopic and highly siderophile element (HSE) concentrations are used to further examine these possible origins, and the crystallization history of the group. In addition, we have begun to assess the possibility of relating certain ungrouped irons with major groups via multi-element, trace element modeling. In a companion abstract, the isotopic and trace element systematics of the ungrouped iron Tishomingo are compared with the IVB irons.

Correlation functional in screened-exchange density functional theory procedures.

PubMed

Chan, Bun; Kawashima, Yukio; Hirao, Kimihiko

2017-10-15

In the present study, we have explored several prospects for the further development of screened-exchange density functional theory (SX-DFT) procedures. Using the performance of HSE06 as our measure, we find that the use of alternative correlation functionals (as oppose to PBEc in HSE06) also yields adequate results for a diverse set of thermochemical properties. We have further examined the performance of new SX-DFT procedures (termed HSEB-type methods) that comprise the HSEx exchange and a (near-optimal) reparametrized B97c (c OS,0  = c SS,0  = 1, c OS,1  = -1.5, c OS,2  = -0.644, c SS,1  = -0.5, and c SS,2  = 1.10) correlation functionals. The different variants of HSEB all perform comparably to or slightly better than the original HSE-type procedures. These results, together with our fundamental analysis of correlation functionals, point toward various directions for advancing SX-DFT methods. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Experimental Study of the Partitioning of Siderophile Elements in a Crystallizing Lunar Magma Ocean

NASA Technical Reports Server (NTRS)

Galenas, M.; Righter, K.; Danielson, L.; Pando, K.; Walker, R. J.

2012-01-01

The distributions of trace elements between the lunar interior and pristine crustal rocks were controlled by the composition of starting materials, lunar core formation, and crystallization of the lunar magma ocean (LMO) [1]. This study focuses on the partitioning of highly siderophile elements (HSE) including Re, Os, Ir, Ru, Pt, Rh, Pd and Au as well as the moderately siderophile elements Mo and W, and the lithophile elements of Hf and Sr. Our experiments also include Ga, which can be slightly siderophile, but is mostly considered to be chalcophile. Partitioning of these elements is not well known at the conditions of a crystallizing LMO. Previous studies of HSE partitioning in silicate systems have yielded highly variable results for differing oxygen fugacity (fO2) and pressure [2-4]. For example, under certain conditions Pt is compatible in clinopy-roxene [2] and Rh and Ru are compatible in olivine [3]. The silicate compositions used for these experiments were nominally basaltic. Ruthenium, Rh, and Pd are incompatible in plagioclase under these conditions[4]. However, this latter study was done at extremely oxidizing conditions and at atmospheric pressure, possibly limiting the applicability for consideration of conditions of a crystallizing LMO. In this study we address the effects of pressure and oxygen fugacity on the crystal/liquid partition coefficients of these trace elements. We are especially interested in the plagioclase/melt partition coefficients so that it may be possible to use reverse modeling to constrain the concentrations of these elements in the lunar mantle through their abundances in pristine crustal rocks.

Application of HSE management in a multi-cultural environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lamki, A.M.N.; Binks, S.L.M.

1996-11-01

This paper addresses the key elements of Petroleum Development Oman L.L.C.`s HSE programmes and the systems employed to structure their application. An improvement in HSE performance with the introduction of HSE programmes and systems is demonstrated. Special emphasis is given to some of the difficulties experienced with application of the systems in a multi-national/cultural workforce. Finally, examples are given of the techniques adopted to promote the application of HSE management in the workforce, with particular emphasis on communication and training.

An Experimental Analog for Metal-Sulfide Partitioning in Acapulcoite-Lodranite Meteorites

NASA Astrophysics Data System (ADS)

Dhaliwal, J. K.; Chabot, N. L.; Ash, R. D.; McCoy, T. J.

2018-05-01

This study builds on prior analyses of highly siderophile element (HSE) abundances in primitive achondrites. We performed melting experiments of naturally occurring FeNi and FeS to examine the effect of sulfur on HSE inter-element partitioning.

Platinum Partitioning at Low Oxygen Fugacity: Implications for Core Formation Processes

NASA Technical Reports Server (NTRS)

Medard, E.; Martin, A. M.; Righter, K.; Lanziroti, A.; Newville, M.

2016-01-01

Highly siderophile elements (HSE = Au, Re, and the Pt-group elements) are tracers of silicate / metal interactions during planetary processes. Since most core-formation models involve some state of equilibrium between liquid silicate and liquid metal, understanding the partioning of highly siderophile elements (HSE) between silicate and metallic melts is a key issue for models of core / mantle equilibria and for core formation scenarios. However, partitioning models for HSE are still inaccurate due to the lack of sufficient experimental constraints to describe the variations of partitioning with key variable like temperature, pressure, and oxygen fugacity. In this abstract, we describe a self-consistent set of experiments aimed at determining the valence of platinum, one of the HSE, in silicate melts. This is a key information required to parameterize the evolution of platinum partitioning with oxygen fugacity.

Mathematical Modeling of the Heat-Shock Response in HeLa Cells

DTIC Science & Technology

2015-07-01

Petre et al. (16), but with some critical changes, which are detailed below. 2HSF4HSF2; (1) HSFþ HSF24HSF3; (2) HSF3 þ HSE4HSF3 : HSE ; (3) HSF3 : HSE ... HSE /HSP : HSFþ HSEþ 2HSF; (10) HSP/; (11) Prot/MFP; (12) HSPþMFP4HSP : MFP; (13) HSP : MFP/HSPþ Prot: (14) The heat-shock response is initiated by a... HSE , heat-shock element; HSF, heat-shock factor; HSP, heat-shock protein; MFP, misfolded protein; mRNA, heat-shock protein messenger RNA; and Prot

Health, safety, and environmental management system operation in contracting companies: A case study.

PubMed

Nassiri, Parvin; Yarahmadi, Rasoul; Gholami, Pari Shafaei; Hamidi, Abdolamir; Mirkazemi, Roksana

2016-05-03

Systematic and cooperative interactions among parent industry and contractors are necessary for a successful health, safety, and environmental management system (HSE-MS). This study was conducted to evaluate the HSE-MS performance in contracting companies in one of the petrochemical industries in Iran during 2013. Managers of parent and contracting companies participated in this study. The data collection forms included 7 elements of an integrated HSE-MS (leadership and commitment; policy and strategic objectives; organization, resources, and documentation; evaluation and risk management; planning; implementation and monitoring; auditing and reviewing). The results showed that mean percentage of the total scores in seven elements of HSE-MS was 85.7% and 87.0% based on self-report and report of parent company, respectively. In conclusion, this study showed that HSE-MS was desirably functioning; however, improvement to ensure health and safety of workers is still required.

Pt, Au, Pd and Ru Partitioning Between Mineral and Silicate Melts: The Role of Metal Nanonuggets

NASA Technical Reports Server (NTRS)

Malavergne, V.; Charon, E.; Jones, J.; Agranier, A.; Campbell, A.

2012-01-01

The partition coefficients of Pt and other Pt Group Elements (PGE) between metal and silicate D(sub Metal-Silicate) and also between silicate minerals and silicate melts D(sub Metal-Silicate) are among the most challenging coefficients to obtain precisely. The PGE are highly siderophile elements (HSE) with D(sub Metal-Silicate) >10(exp 3) due to the fact that their concentrations in silicates are very low (ppb to ppt range). Therefore, the analytical difficulty is increased by the possible presence of HSE-rich-nuggets in reduced silicate melts during experiments). These tiny HSE nuggets complicate the interpretation of measured HSE concentrations. If the HSE micro-nuggets are just sample artifacts, then their contributions should be removed before calculations of the final concentration. On the other hand, if they are produced during the quench, then they should be included in the analysis. We still don't understand the mechanism of nugget formation well. Are they formed during the quench by precipitation from precursor species dissolved homogeneously in the melts, or are they precipitated in situ at high temperature due to oversaturation? As these elements are important tracers of early planetary processes such as core formation, it is important to take up this analytical and experimental challenge. In the case of the Earth for example, chondritic relative abundances of the HSE in some mantle xenoliths have led to the concept of the "late veneer" as a source of volatiles (such as water) and siderophiles in the silicate Earth. Silicate crystal/liquid fractionation is responsible for most, if not all, the HSE variation in the martian meteorite suites (SNC) and Pt is the element least affected by these fractionations. Therefore, in terms of reconstructing mantle HSE abundances for Mars, Pt becomes a very important player. In the present study, we have performed high temperature experiments under various redox conditions in order to determine the abundances of Pt, Au, Ru and Pd in minerals (olivine and diopside) and in silicate melts, but also to characterize the sizes, density and chemistry of HSE nuggets when present in the samples.

Origin and mixing timescale of Earth's late veneer

NASA Astrophysics Data System (ADS)

Prescher, C.; Allu Peddinti, D.; Bell, E. A.; Bello, L.; Cernok, A.; Ghosh, N.; Tucker, J.; Wielicki, M. M.; Zahnle, K. J.

2012-12-01

Experimental studies on the partitioning behavior of highly siderophile elements (HSE) between silicate and metallic melts imply that the Earth's mantle should have been highly depleted in these elements by core formation in an early magma ocean. However, present HSE contents of the Earth's mantle are ~3 orders of magnitude higher than that expected by experiments. The apparent over-abundance of HSE has commonly been explained by the addition of meteoritic material in the "late veneer" which describes the exogenous mass addition following the moon forming impact and concluding with the late heavy bombardment at ~3.8-3.9 Ga. The strongest evidence for this theory is that the platinum group element (PGE) contents in today's mantle are present in chondritic relative abundances, as opposed to a fractionated pattern expected with metal-silicate partitioning. Archean komatiites indicate that the PGE content of the Earth's mantle increased from about half their present abundances at 3.5 Ga to their present abundances at 2.9 Ga. This secular increase in PGE content suggests a progressive mixing of the late veneer material into the Earth's mantle. However, this time scale also implies that the whole mantle was relatively well mixed by 2.9 Ga. We use a compilation of existing isotopic and trace element data in order to constrain the origin and composition of the late veneer. We use PGE abundances, W abundances and W isotopic compositions in chondritic meteorites and the primitive upper mantle to compute the amount of mass delivered during the late veneer and find the late veneer mass to be ~0.6 % the mass of the bulk silicate Earth (consistent with earlier estimates). We also use the 187Re-187Os and 190Pt-186Os systems to constrain the composition and timing of delivery of the impacting population. We model the efficiency of mantle mixing in this time frame by using 3-dimensional numerical geodynamical simulations and geochemical constraints. Initial parameters include the amount of mass delivered in the late veneer and the Archean internal heating which is at least 4 times higher than the present values, due to the higher abundance of radioactive elements. Another important parameter is the mechanism of mass addition to the Earth. We test three end-member scenarios: (1) a single very large impactor accounting for the entire mass addition, (2) sprinkling of a large number of small impactors over the whole Earth which then mix into the mantle, or (3) by using a size/frequency distribution estimated from the lunar cratering record and corrected for the difference in gravitational cross section of the Earth and the Moon. This project results from collaborations begun at the CIDER II workshop held at KITP, UCSB, 2012.

Lithological, Chemical and Chronological Constraints on Melt Extraction from the Mantle Section of the ~492 Ma Shetland Ophiolite Complex, Scotland

NASA Astrophysics Data System (ADS)

O'Driscoll, B.; Walker, R. J.; Clay, P. L.; Day, J. M.; Ash, R. D.; Daly, J. S.

2015-12-01

The mantle sections of ophiolites offer a means of studying the composition and structure of the oceanic mantle. In particular, the relations between different lithologies can be established in the field, permitting an assessment of the relative timing of processes such as melt extraction and melt-rock reaction. The Shetland Ophiolite Complex (SOC) contains a well-preserved mantle section that is dominated by harzburgite (≥70 vol.%), with dominantly chondritic present-day 187Os/188Os compositions1. Melt extraction and melt-rock reaction is evident in the form of dunite and chromitite layers and lenses, with thicknesses ranging from millimetres-to-metres. These lithologies are characteristic of supra-subduction zone processing and are considered to relate to closure of the Iapetus Ocean at ~492 Ma1. However, evidence of much earlier melt extraction has been suggested for some SOC harzburgites, which have relatively unradiogenic 187Os/188Os compositions that yield TRD model ages as old as ~1.4 Ga1. In order to assess the scales at which such compositional heterogeneities are preserved in the mantle, a small (45 m2) area of the SOC mantle section was selected for detailed lithological mapping and sampling. A selection of harzburgites (n=8), dunites (n=6) and pyroxenites (n=2) from this area has been analysed for their Os isotope and highly-siderophile element (HSE) compositions. Six of the harzburgites and four of the dunites have relative HSE abundances and gOs values that are approximately chondritic, with gOs ranging only from -0.6 to +2.7 (n=10). Two dunites have more radiogenic gOs (up to +7.5), that is correlated with enhanced concentrations of accessory base-metal sulphides, suggesting formation via melt percolation and melt-rock reaction. The two remaining harzburgites have less radiogenic gOs (-3.5 and -4), yielding Mesoproterozoic TRD ages. The new data indicate that a comparable range of Os isotope compositions to that previously measured across the entire SOC mantle section is present in the mapped area, i.e., at the m2 scale, revealing the modest scale of isotopic and chemical heterogeneity in the oceanic mantle. 1O'Driscoll B, Day JMD, Walker RJ, Daly JS, McDonough WF, Piccoli PM (2012). Earth and Planetary Science Letters 333-334: 226-237.

Group IVA irons: New constraints on the crystallization and cooling history of an asteroidal core with a complex history

NASA Astrophysics Data System (ADS)

McCoy, T. J.; Walker, R. J.; Goldstein, J. I.; Yang, J.; McDonough, W. F.; Rumble, D.; Chabot, N. L.; Ash, R. D.; Corrigan, C. M.; Michael, J. R.; Kotula, P. G.

2011-11-01

We report analyses of 14 group IVA iron meteorites, and the ungrouped but possibly related, Elephant Moraine (EET) 83230, for siderophile elements by laser ablation ICP-MS and isotope dilution. EET was also analyzed for oxygen isotopic composition and metallographic structure, and Fuzzy Creek, currently the IVA with the highest Ni concentration, was analyzed for metallographic structure. Highly siderophile elements (HSE) Re, Os and Ir concentrations vary by nearly three orders of magnitude over the entire range of IVA irons, while Ru, Pt and Pd vary by less than factors of five. Chondrite normalized abundances of HSE form nested patterns consistent with progressive crystal-liquid fractionation. Attempts to collectively model the HSE abundances resulting from fractional crystallization achieved best results for 3 wt.% S, compared to 0.5 or 9 wt.% S. Consistent with prior studies, concentrations of HSE and other refractory siderophile elements estimated for the bulk IVA core and its parent body are in generally chondritic proportions. Projected abundances of Pd and Au, relative to more refractory HSE, are slightly elevated and modestly differ from L/LL chondrites, which some have linked with group IVA, based on oxygen isotope similarities. Abundance trends for the moderately volatile and siderophile element Ga cannot be adequately modeled for any S concentration, the cause of which remains enigmatic. Further, concentrations of some moderately volatile and siderophile elements indicate marked, progressive depletions in the IVA system. However, if the IVA core began crystallization with ˜3 wt.% S, depletions of more volatile elements cannot be explained as a result of prior volatilization/condensation processes. The initial IVA core had an approximately chondritic Ni/Co ratio, but a fractionated Fe/Ni ratio of ˜10, indicates an Fe-depleted core. This composition is most easily accounted for by assuming that the surrounding silicate shell was enriched in iron, consistent with an oxidized parent body. The depletions in Ga may reflect decreased siderophilic behavior in a relatively oxidized body, and more favorable partitioning into the silicate portion of the parent body. Phosphate inclusions in EET show Δ 17O values within the range measured for silicates in IVA iron meteorites. EET has a typical ataxitic microstructure with precipitates of kamacite within a matrix of plessite. Chemical and isotopic evidence for a genetic relation between EET and group IVA is strong, but the high Ni content and the newly determined, rapid cooling rate of this meteorite show that it should continue to be classified as ungrouped. Previously reported metallographic cooling rates for IVA iron meteorites have been interpreted to indicate an inwardly crystallizing, ˜150 km radius metallic body with little or no silicate mantle. Hence, the IVA group was likely formed as a mass of molten metal separated from a much larger parent body that was broken apart by a large impact. Given the apparent genetic relation with IVA, EET was most likely generated via crystal-liquid fractionation in another, smaller body spawned from the same initial liquid during the impact event that generated the IVA body.

The Osmium Isotopic Composition of Tagish Lake and Other Chondrites, Implications for Late Terrestrial Planetary Accretion

NASA Technical Reports Server (NTRS)

Brandon, A. D.

2003-01-01

The goals of this investigation are twofold. First, obtain high-precision Os isotope measurements of Tagish Lake and other chondrites by TIMS. Second, measure Re, Os, Pt, and other HSE concentrations by isotope dilution using TIMS and ICPMS. These measurements will determine whether this meteorite does in fact represent C-chondrite material with timeintegrated elevated Re/Os and Pt/Os with the implications to late accretion material characteristics.

Meter Scale Heterogeneities in the Oceanic Mantle Revealed in Ophiolites Peridotites

NASA Astrophysics Data System (ADS)

Haller, M. B.; Walker, R. J.; Day, J. M.; O'Driscoll, B.; Daly, J. S.

2016-12-01

Mid-ocean ridge basalts and other oceanic mantle-derived rocks do not capture the depleted endmember isotopic compositions present in oceanic peridotites. Ophiolites are especially useful in interrogating this issue as field-based observations can be paired with geochemical investigations over a wide range of geologic time. Grid sampling methods (3m x 3m) at the 497 Ma Leka Ophiolite Complex (LOC), Norway, and the 1.95 Ga Jormua Ophiolite Complex (JOC), Finland, offer an opportunity to study mantle domains at the meter and kilometer scale, and over a one billion year timespan. The lithology of each locality predominately comprises harzburgite, hosting layers and lenses of dunite and pyroxenite. Here, we combine highly siderophile elements (HSE) and Re-Os isotopic analysis of these rocks with major and trace element measurements. Harzburgites at individual LOC grid sites show variations in γOs(497 Ma) (-2.1 to +2.2) at the meter scale. Analyses of adjacent, more radiogenic dunites within the same LOC grid, reveal that dunites may either have similar γOs to their host harzburgite, or different, implying interactions between spatially associated rock types may differ at the meter scale. Averaged γOs values between the mantle sections of two LOC grid sites (+1.3 and -0.4) separated by 5 km indicate km-scale heterogeneity in the convecting upper mantle. Pd/Ir and Ru/Ir ratios are scattered and do not obviously correlate with γOs values. Analyses of pyroxenites within LOC grid sections, thin section observations of relict olivine grains, and whole rock major and trace element data are also examined to shed light on the causes of the isotopic heterogeneities in the LOC. Data from JOC grid sampling will be presented as well.

Controls on Highly Siderophile Element Concentrations in Martian Basalt: Sulfide Saturation and Under-Saturation

NASA Technical Reports Server (NTRS)

Righter, Kevin

2009-01-01

Highly siderophile elements (HSE; Re, Au and the platinum group elements) in shergottites exhibit a wide range from very high, similar to the terrestrial mantle, to very low, similar to sulfide saturated mid ocean ridge basalt (e.g., [1]). This large range has been difficult to explain without good constraints on sulfide saturation or under-saturation [2]. A new model for prediction of sulfide saturation places new constraints on this problem [3]. Shergottite data: For primitive shergottites, pressure and temperature estimates are between 1.2-1.5 GPa, and 1350-1470 C [4]. The range of oxygen fugacities is from FMQ-2 to IW, where the amount of Fe2O3 is low and thus does not have a significant effect on the S saturation values. Finally, the bulk compositions of shergottites have been reported in many recent studies (e.g., [5]). All of this information will be used to test whether shergottites are sulfide saturated [3]. Modeling values and results: The database for HSE partition coefficients has been growing with many new data for silicates and oxides [6-8] to complement a large sulfide database [9- 11]. Combining these data with simple batch melting models allows HSE contents of mantle melts to be estimated for sulfide-bearing vs. sulfide-free mantle. Combining such models with fractional crystallization modeling (e.g., [12]) allows HSE contents of more evolved liquids to be modeled. Most primitive shergottites have high HSE contents (and low S contents) that can be explained by sulfide under-saturated melting of the mantle. An exception is Dhofar 019 which has high S contents and very low HSE contents suggesting sulfide saturation. Most evolved basaltic shergottites have lower S contents than saturation, and intermediate HSE contents that can be explained by olivine, pyroxene, and chromite fractionation. An exception is EET A79001 lithology B, which has very low HSE contents and S contents higher than sulfide saturation values . evidence for sulfide saturation during late fractional crystallization. These results show that shergottite HSE contents are controlled by silicates, oxides, and sulfides. In addition, the mantle producing the most primitive shergottites did not contain near chondritic relative ratios of the HSEs like the terrestrial mantle, and did not experience a late chondritic veneer.

Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions.

PubMed

Bennett, Neil R; Brenan, James M; Fei, Yingwei

2015-06-13

Estimates of the primitive upper mantle (PUM) composition reveal a depletion in many of the siderophile (iron-loving) elements, thought to result from their extraction to the core during terrestrial accretion. Experiments to investigate the partitioning of these elements between metal and silicate melts suggest that the PUM composition is best matched if metal-silicate equilibrium occurred at high pressures and temperatures, in a deep magma ocean environment. The behavior of the most highly siderophile elements (HSEs) during this process however, has remained enigmatic. Silicate run-products from HSE solubility experiments are commonly contaminated by dispersed metal inclusions that hinder the measurement of element concentrations in the melt. The resulting uncertainty over the true solubility and metal-silicate partitioning of these elements has made it difficult to predict their expected depletion in PUM. Recently, several studies have employed changes to the experimental design used for high pressure and temperature solubility experiments in order to suppress the formation of metal inclusions. The addition of Au (Re, Os, Ir, Ru experiments) or elemental Si (Pt experiments) to the sample acts to alter either the geometry or rate of sample reduction respectively, in order to avoid transient metal oversaturation of the silicate melt. This contribution outlines procedures for using the piston-cylinder and multi-anvil apparatus to conduct solubility and metal-silicate partitioning experiments respectively. A protocol is also described for the synthesis of uncontaminated run-products from HSE solubility experiments in which the oxygen fugacity is similar to that during terrestrial core-formation. Time-resolved LA-ICP-MS spectra are presented as evidence for the absence of metal-inclusions in run-products from earlier studies, and also confirm that the technique may be extended to investigate Ru. Examples are also given of how these data may be applied.

Chalcophile and siderophile elements in sulphide inclusions in eclogitic diamonds and metal cycling in a Paleoproterozoic subduction zone

NASA Astrophysics Data System (ADS)

Aulbach, Sonja; Stachel, Thomas; Seitz, Hans-Michael; Brey, Gerhard P.

2012-09-01

In the central Slave craton, eclogitic diamonds are suggested to have formed during Paleoproterozoic subduction in a meta-gabbroic substrate representing former lower oceanic crust that interacted with serpentinite-derived fluids at high fluid-rock ratios. In order to assess the behaviour of chalcophile and siderophile elements (CSE) during this process, we measured trace-element concentrations of sulphide inclusions in diamonds from the Diavik mine by laser ablation ICPMS. The nitrogen systematics of the diamonds (average N concentration of ˜600 ppm and aggregation state 4% N as B-aggregates) indicate average mantle residence temperatures of ˜1050 °C for a 1.85 Ga formation age, corresponding ˜170 km depth. Based on the available evidence from natural samples and experiments, we suggest that the highly siderophile elements (HSE: Os, Ir, Ru, Rh, Pd, Pt, Re) except Au behaved largely conservatively during fluid-induced metamorphism, which may point to a reducing and Cl-poor nature of the fluid. The abundances of the moderately siderophile and chalcophile elements Cr, Co, Ni, Cu, Ag, Sn, Mo and W may also have changed little, whereas As, Sb, Tl, Pb and Bi may have been mobilised from the subducting lower oceanic crust. The partitioning of CSE in eclogite and geochemical behaviour during oceanic crust formation was assessed for inferred conservative elements. Assuming an average sulphide mode of 0.3 wt.% for the oceanic crust, its abundances of HSE, Cu, Mo, Se and Te can mostly be accounted for by sulphide minerals alone. Lithophile behaviour of W, Cd, In and Sn and enrichment in residual melts may explain their lower abundances in the gabbroic eclogitic sulphide inclusions compared to MORB sulphide. These elements, as well as Cr, Co, Ni, Zn and Ga require additional host phases both in eclogite, where rutile partitions significant amounts of Cr, Zn, W, Ga and Sn, and in the oceanic crust.

Metal-silicate Partitioning at High Pressure and Temperature: Experimental Methods and a Protocol to Suppress Highly Siderophile Element Inclusions

PubMed Central

Bennett, Neil R.; Brenan, James M.; Fei, Yingwei

2015-01-01

Estimates of the primitive upper mantle (PUM) composition reveal a depletion in many of the siderophile (iron-loving) elements, thought to result from their extraction to the core during terrestrial accretion. Experiments to investigate the partitioning of these elements between metal and silicate melts suggest that the PUM composition is best matched if metal-silicate equilibrium occurred at high pressures and temperatures, in a deep magma ocean environment. The behavior of the most highly siderophile elements (HSEs) during this process however, has remained enigmatic. Silicate run-products from HSE solubility experiments are commonly contaminated by dispersed metal inclusions that hinder the measurement of element concentrations in the melt. The resulting uncertainty over the true solubility and metal-silicate partitioning of these elements has made it difficult to predict their expected depletion in PUM. Recently, several studies have employed changes to the experimental design used for high pressure and temperature solubility experiments in order to suppress the formation of metal inclusions. The addition of Au (Re, Os, Ir, Ru experiments) or elemental Si (Pt experiments) to the sample acts to alter either the geometry or rate of sample reduction respectively, in order to avoid transient metal oversaturation of the silicate melt. This contribution outlines procedures for using the piston-cylinder and multi-anvil apparatus to conduct solubility and metal-silicate partitioning experiments respectively. A protocol is also described for the synthesis of uncontaminated run-products from HSE solubility experiments in which the oxygen fugacity is similar to that during terrestrial core-formation. Time-resolved LA-ICP-MS spectra are presented as evidence for the absence of metal-inclusions in run-products from earlier studies, and also confirm that the technique may be extended to investigate Ru. Examples are also given of how these data may be applied. PMID:26132380

Origin of felsic achondrites Graves Nunataks 06128 and 06129, and ultramafic brachinites and brachinite-like achondrites by partial melting of volatile-rich primitive parent bodies

NASA Astrophysics Data System (ADS)

Day, James M. D.; Walker, Richard J.; Ash, Richard D.; Liu, Yang; Rumble, Douglas; Irving, Anthony J.; Goodrich, Cyrena A.; Tait, Kimberly; McDonough, William F.; Taylor, Lawrence A.

2012-03-01

New major- and trace-element abundances, highly siderophile element (HSE: Os, Ir, Ru, Pt, Pd, Re) abundances, and oxygen and rhenium-osmium isotope data are reported for oligoclase-rich meteorites Graves Nunataks 06128 and 06129 (GRA 06128/9), six brachinites (Brachina; Elephant Morraine 99402/7; Northwest Africa (NWA) 1500; NWA 3151; NWA 4872; NWA 4882) and three olivine-rich achondrites, which are referred to here as brachinite-like achondrites (NWA 5400; NWA 6077; Zag (b)). GRA 06128/9 represent examples of felsic and highly-sodic melt products from an asteroid that may provide a differentiation complement to brachinites and/or brachinite-like achondrites. The new data, together with our petrological observations, are consistent with derivation of GRA 06128/9, brachinites and the three brachinite-like achondrites from nominally volatile-rich and oxidised 'chondritic' precursor sources within their respective parent bodies. Furthermore, the range of Δ17O values (˜0‰ to -0.3‰) among the meteorites indicates generation from isotopically heterogeneous sources that never completely melted, or isotopically homogenised. It is possible to generate major- and trace-element compositions similar to brachinites and the three studied brachinite-like achondrites as residues of moderate degrees (13-30%) of partial melting of primitive chondritic sources. This process was coupled with inefficient removal of silica-saturated, high Fe/Mg felsic melts with compositions similar to GRA 06128/9. Melting of the parent bodies of GRA 06128/9, brachinites and brachinite-like achondrites halted well before extensive differentiation, possibly due to the exhaustion of the short-lived radionuclide 26Al by felsic melt segregation. This mechanism provides a potential explanation for the cessation of run-away melting in asteroids to preserve achondrites such as GRA 06128/9, brachinites, brachinite-like achondrites, acapulcoite-lodranites, ureilites and aubrites. Moderate degrees of partial melting of chondritic material and generation of Fe-Ni-S-bearing melts are generally consistent with HSE abundances that are within factors of ˜2-10 × CI-chondrite abundances for GRA 06128/9, brachinites and the three brachinite-like achondrites. However, in detail, brachinite-like achondrites NWA 5400, NWA 6077 and Zag (b) are interpreted to have witnessed single-stage S-rich metal segregation, whereas HSE in GRA 06128/9 and brachinites have more complex heritages. The HSE compositions of GRA 06128/9 and brachinites require either: (1) multiple phases in the residue (e.g., metal and sulphide); (2) fractionation after generation of an initial melt, again involving multiple phases; (3) fractional fusion, or; (4) a parent body with non-chondritic relative HSE abundances. Petrological and geochemical observations permit genetic links (i.e., same parent body) between GRA 06128/9 and brachinites and similar formation mechanisms for brachinites and brachinite-like achondrites.

Highly Siderophile and Chalcophile Elements in Lunar Impact Rocks: Constraints on the Composition of Late Accreted Material

NASA Astrophysics Data System (ADS)

Gleißner, P.; Becker, H.

2016-08-01

HSE, Te, Se and S composition of ancient lunar impactites reveal the late accretion of chondrite-like material along with differentiated core metal. HSE patterns are consistent with parent body P/S ratios higher than most magmatic iron meteorites.

Partitioning of Pd Between Fe-S-C and Mantle Liquids at High Pressure and Temperature: Implications for Core Formation

NASA Technical Reports Server (NTRS)

Righter, K.; Humayun, M.; Danielson, L.

2007-01-01

One of the most elusive geochemical aspects of the early Earth has been explaining the near chondritic relative abundances of the highly siderophile elements (HSE; Au, Re and the platinum group elements) in Earth's primitive upper mantle (PUM). Perhaps they were delivered to the Earth after core formation, by late addition of carbonaceous chondrite material. However, the recognition that many moderately siderophile elements can be explained by high pressure and temperature (PT) metal-silicate equilibrium, leads to the question whether high PT equilibrium can also explain the HSE concentrations. Answers to this question have been slowed by experimental difficulties (nugget effect and very low solubilities). But two different perspectives have emerged from recent studies. One perspective is that D(M/S) for HSE at high PT are not low enough to explain terrestrial mantle depletions of these elements (for Pd and Pt). A second perspective is D(M/S) are reduced substantially at high PT and even low enough to explain terrestrial mantle depletions (for Au and Pt). Issues complicating interpretation of all experiments include use of MgO- and FeO-free silicate melts, and S-free and FeNi metal-free systems. In addition, conclusions for Pt rest on an interpretation that the tiny metallic nuggets plaguing many such experiments, were formed upon quench. There is not agreement on this issue, and the general question of HSE solubility at high PT remains unresolved

High Pressure and Temperature Core Formation as an Alternative to the "Late Veneer" Hypothesis

NASA Technical Reports Server (NTRS)

Righter, Kevin; Pando, K.; Humayun, M.; Danielson, L.

2011-01-01

The highly siderophile elements (HSE; Re, Au and the Platinum Group Elements - Pd Pt, Rh, Ru, Ir, Os) are commonly utilized to constrain accretion processes in terrestrial differentiated bodies due to their affinity for FeNi metal [1]. These eight elements exhibit highly siderophile behavior, but nonetheless have highly diverse metal-silicate partition coefficients [2]. Therefore the near chondritic relative concentrations of HSEs in the terrestrial and lunar mantles, as well as some other bodies, are attributed to late accretion rather than core formation [1]. Evaluation of competing theories, such as high pressure metal-silicate partitioning or magma ocean hypotheses has been hindered by a lack of relevant partitioning data for this group of eight elements. In particular, systematic studies isolating the effect of one variable (e.g. temperature or melt compositions) are lacking. Here we undertake new experiments on all eight elements, using Fe metal and FeO-bearing silicate melts at fixed pressure, but variable temperatures. These experiments, as well as some additional planned experiments should allow partition coefficients to be more accurately calculated or estimated at the PT conditions and compositions at which core formation is thought to have occurred.

Characterization of the Distribution of Siderophile and Highly Siderophile Elements in the Milton and Eagle Station Pallasites

NASA Technical Reports Server (NTRS)

Hillebrand, J. T.; McDonough, W. F.; Walker, R. J.; Piccoli, P. M.

2004-01-01

We examine the partitioning characteristics of several siderophile elements and HSE in the Eagle Station and Milton pallasites to determine if the D(sup Metal/Silicate) in natural systems are comparable to the range of values determined for synthetic systems. Eagle Station and Milton are particularly appropriate for this type of study because previous studies have shown that bulk samples of these meteorites have much higher abundances of siderophile elements and HSE than bulk samples of main group pallasites or mesosiderites. Thus, the expectation that initiated this study was that the abundances of at least some elements of interest present in the silicate phases may be at levels sufficiently high to be determined via in situ spot analysis using laser ablation ICP-MS.

Diffusion of Siderophile Elements in Fe Metal: Application to Zoned Metal Grains in Chondrites

NASA Technical Reports Server (NTRS)

Righter, K.; Campbell, A. J.; Humajun, M.

2003-01-01

The distribution of highly siderophile elements (HSE) in planetary materials is controlled mainly by metal. Diffusion processes can control the distribution or re-distribution of these elements within metals, yet there is little systematic or appropriate diffusion data that can be used to interpret HSE concentrations in such metals. Because our understanding of isotope chronometry, redox processes, kamacite/taenite-based cooling rates, and metal grain zoning would be enhanced with diffusion data, we have measured diffusion coefficients for Ni, Co, Ga, Ge, Ru, Pd, Ir and Au in Fe metal from 1200 to 1400 C and 1 bar and 10 kbar. These new data on refractory and volatile siderophile elements are used to evaluate the role of diffusional processes in controlling zoning patterns in metal-rich chondrites.

Early Terrestrial Mantle Differentiation Recorded in Paleoarchean Komatiites

NASA Astrophysics Data System (ADS)

Puchtel, I. S.; Blichert-Toft, J.; Touboul, M.; Horan, M. F.; Walker, R. J.

2016-12-01

Geochmical signatures generated in the manle as a result of radioactive decay of short- and long-lived nuclides can be used to constrain the timing of formation and the nature of now mostly vanished early terrestrial reservoirs. The 3.55 Ga komatiites from the Schapenburg Greenstone Remnant (SGR) located in the Barberton Greenstone Belt in South Africa have a unique combination of trace element abundances and isotopic compositions that place strong constraints on the origin of these reservoirs. The SGR komatiites define a Re-Os isochron with an age of 3550±87 Ma and an initial γ187Os = +3.7±0.2 (2SD). The absolute HSE abundances in the mantle source of the SGR komatiite system are estimated to be only 29±5% of those in the present-day bulk silicate Earth (BSE) estimates. The SGR komatiites show coupled depletion, relative to the modern mantle, in 142Nd and 182W (μ142Nd = -5.0±2.8, μ182W = -8.4±4.5), the decay products of the short-lived 146Sm and 182Hf nuclides, respectively, indicating derivation from a mantle domain that was enriched in incompatible elements 30 Ma after Solar System formation. Early Hadean contributors to this mantle domain could include high-pressure fractionates from a primordial magma ocean. By contrast, the long-lived Sm-Nd and Lu-Hf isotope systems (ɛ143Nd = +2.4±0.1, ɛ176Hf = +5.7±0.3) indicate that the mantle domain that the SGR komatiites were ultimately derived from underwent additional processing after the early Hadean, including melt depletion at lower pressures. The preservation of early-formed 182W and 142Nd anomalies in the mantle until at least 3.55 Ga indicates that the products of early planetary differentiation survived both later planetary accretion and convective mantle mixing during the Hadean. This study lends further support to the notion that variable late accretion, by itself, cannot account for all of the observed W isotope and absolute and relative HSE abundance variations in the Archean mantle recorded by komatiites.

Anionic Pt in Silicate Melts at Low Oxygen Fugacity: Speciation, Partitioning and Implications for Core Formation Processes on Asteroids

NASA Technical Reports Server (NTRS)

Medard, E.; Martin, A. M.; Righter, K.; Malouta, A.; Lee, C.-T.

2017-01-01

Most siderophile element concentrations in planetary mantles can be explained by metal/ silicate equilibration at high temperature and pressure during core formation. Highly siderophile elements (HSE = Au, Re, and the Pt-group elements), however, usually have higher mantle abundances than predicted by partitioning models, suggesting that their concentrations have been set by late accretion of material that did not equilibrate with the core. The partitioning of HSE at the low oxygen fugacities relevant for core formation is however poorly constrained due to the lack of sufficient experimental constraints to describe the variations of partitioning with key variables like temperature, pressure, and oxygen fugacity. To better understand the relative roles of metal/silicate partitioning and late accretion, we performed a self-consistent set of experiments that parameterizes the influence of oxygen fugacity, temperature and melt composition on the partitioning of Pt, one of the HSE, between metal and silicate melts. The major outcome of this project is the fact that Pt dissolves in an anionic form in silicate melts, causing a dependence of partitioning on oxygen fugacity opposite to that reported in previous studies.

A Novel Heat Shock Element (HSE) in Entamoeba histolytica that Regulates the Transcriptional Activation of the EhPgp5 Gene in the Presence of Emetine Drug.

PubMed

Nieto, Alma; Pérez Ishiwara, David G; Orozco, Esther; Sánchez Monroy, Virginia; Gómez García, Consuelo

2017-01-01

Transcriptional regulation of the multidrug resistance EhPgp5 gene in Entamoeba histolytica is induced by emetine stress. EhPgp5 overexpression alters the chloride-dependent currents that cause trophozoite swelling, diminishing induced programmed cell death (PCD) susceptibility. In contrast, antisense inhibition of P-glycoprotein (PGP) expression produces synchronous death of trophozoites and the enhancement of the biochemical and morphological characteristics of PCD induced by G418. Transcriptional gene regulation analysis identified a 59 bp region at position -170 to -111 bp promoter as putative emetine response elements (EREs). However, insights into transcription factors controlling EhPgp5 gene transcription are missing; to fill this knowledge gap, we used deletion studies and transient CAT activity assays. Our findings suggested an activating motif (-151 to -136 bp) that corresponds to a heat shock element (HSE). Gel-shift assays, UV-crosslinking, binding protein purification, and western blotting assays revealed proteins of 94, 66, 62, and 51 kDa binding to the EhPgp5 HSE that could be heat shock-like transcription factors that regulate the transcriptional activation of the EhPgp5 gene in the presence of emetine drug.

Rsp5-Bul1/2 complex is necessary for the HSE-mediated gene expression in budding yeast.

PubMed

Kaida, Daisuke; Toh-e, Akio; Kikuchi, Yoshiko

2003-07-11

Rsp5 is an essential ubiquitin ligase in Saccharomyces cerevisiae and is concerned with many functions such as endocytosis and transcription through ubiquitination of various substrates. Bul1 or its homologue Bul2 binds to Rsp5 through the PY-motif and the bul1 bul2 double mutant is sensitive to various stresses. We demonstrate here that heat shock element (HSE)-mediated gene expression was defective in both rsp5-101 and bul1 bul2 mutants under high temperature condition. The bul1 gene containing mutations in the PY motif region did not recover this defective gene expression of the bul1 bul2 mutant. The protein level and phosphorylation state of the HSE-binding transcription factor, Hsf1, was not affected by these mutations. Thus, the Rsp5-Bul1/2 complex has a new function for the HSE-mediated gene expression and may regulate it through other factors than Hsf1.

A Novel Heat Shock Element (HSE) in Entamoeba histolytica that Regulates the Transcriptional Activation of the EhPgp5 Gene in the Presence of Emetine Drug

PubMed Central

Nieto, Alma; Pérez Ishiwara, David G.; Orozco, Esther; Sánchez Monroy, Virginia; Gómez García, Consuelo

2017-01-01

Transcriptional regulation of the multidrug resistance EhPgp5 gene in Entamoeba histolytica is induced by emetine stress. EhPgp5 overexpression alters the chloride-dependent currents that cause trophozoite swelling, diminishing induced programmed cell death (PCD) susceptibility. In contrast, antisense inhibition of P-glycoprotein (PGP) expression produces synchronous death of trophozoites and the enhancement of the biochemical and morphological characteristics of PCD induced by G418. Transcriptional gene regulation analysis identified a 59 bp region at position −170 to −111 bp promoter as putative emetine response elements (EREs). However, insights into transcription factors controlling EhPgp5 gene transcription are missing; to fill this knowledge gap, we used deletion studies and transient CAT activity assays. Our findings suggested an activating motif (−151 to −136 bp) that corresponds to a heat shock element (HSE). Gel-shift assays, UV-crosslinking, binding protein purification, and western blotting assays revealed proteins of 94, 66, 62, and 51 kDa binding to the EhPgp5 HSE that could be heat shock-like transcription factors that regulate the transcriptional activation of the EhPgp5 gene in the presence of emetine drug. PMID:29238701

A Partial Late Veneer for the Source of 3.8 Ga Isua Rocks: Evidence from Highly Siderophile Elements and 182W

NASA Astrophysics Data System (ADS)

Dale, C.; Kruijer, T.; Burton, K. W.; Kleine, T.; Moorbath, S.

2015-12-01

Highly siderophile elements (HSE) were strongly sequestered into metallic planetary cores, leaving silicate mantles almost devoid of HSE. Late accretion partially replenished HSE in planetary mantles soon after core formation had ceased [1], which for Earth probably postdated the giant Moon-forming impact. Ancient isolated domains in Earth's mantle - such as the source of 3.8 Ga Isua basalts - might represent mantle isolated from late accreted material, as suggested based on their small 182W excesses compared to Earth's present-day mantle [2]. However, such 182W excesses may also represent signatures of early differentiation in Earth's mantle, which have been preserved through the giant impact [3]. To assess the origin of 182W anomalies and the 182W composition of the pre-late veneer mantle, we determined HSE abundances and 182W compositions of a suite of mafic to ultramafic rocks from Isua. Our data show that the Isua source mantle had HSE abundances at ~60% of the present-day mantle, inconsistent with isolation from the late veneer. For the same samples we obtained a 13±4 ppm 182W excess over the modern terrestrial mantle, in excellent agreement with previous data [2]. Using a range of possible late veneer compositions and taking into account the recently revised 182W value for the Moon [4], we calculate that the Isua mantle source, containing 60% late veneer, would have a 182W value of 9±4 ppm, in very good agreement with the measured value for Isua. The combined HSE-W data, therefore, are consistent with only partial addition of the late veneer to the Isua mantle source, and with the interpretation that the 27±4 ppm 182W excess of the Moon represents the 182W composition of the pre-late veneer Earth's mantle [4]. [1] Dale et al. (2012) Science 336, 72. [2] Willbold et al. (2011) Nature 477, 195. [3] Touboul et al. (2012) Science 335, 1065-1069. [4] Kruijer et al. (2015) Nature 7548, 534

The Delivery of Water to the Lunar Mantle by Late Planetesimal Accretion (Invited)

NASA Astrophysics Data System (ADS)

Bottke, W. F.; Walker, R. J.; Day, J.; Nesvorny, D.; Elkins-Tanton, L. T.

2010-12-01

The final stages of planet formation in the inner Solar System are thought to have culminated in enormous planetary collisions, such as the hypothesized ‘giant impact’ origin for the Earth and Moon that occurred ~50-100 My after the formation of the first Solar System solids. The giant impact event probably triggered a final phase of core formation on these worlds, with global magma oceans effectively stripping the terrestrial and lunar mantles of highly siderophile elements (HSE; Re, Os, Ir, Ru, Pt, Rh, Pd, Au), which have extremely high metal-silicate partition coefficients. Studies of mantle-derived terrestrial peridotites and derivative lunar mantle melts, however, show that the terrestrial and lunar mantles have elevated absolute, and approximately chondritic relative abundances of highly siderophile elements (HSE). We argue this material was most likely delivered by continued planetesimal accretion via HSE-rich impactors within tens of My of core formation termination, with subsequently-accreted materials mixed into each mantle by convection. This process, often called the “late veneer” but here termed late accretion, delivered > 0.4% Earth masses to the terrestrial mantle and produced an Earth/Moon mass input ratio of ~1,000. Using Monte Carlo models, we found that this high ratio most likely came from planetesimal populations dominated by massive impactors. Specifically, if the late accretion population had the form dN ∝ D-q dD (i.e., dN is the number of planetesimals of diameter D within bin dD), the power law index of the projectiles was q < 2 for 200 < D < 4000 km. Interestingly, q ~ 2 populations are also found in planetesimal size distributions derived from evidence taken near 1 AU (e.g., D > 250 km asteroids in the inner/central main belt with semimajor axis < 2.8 AU, the population of non-saturated ancient martian impact basins with 700 < D < 2000 km) as well as from new planetary accretion models that allow planetesimals to be “born big” via turbulent concentration mechanisms in the gas disk. Using a q ~ 2 size distribution and HSE constraints, we predict the largest late accretion impactors to strike the Earth and Moon, on average, were D = 2,500-3,000 km and 250-300 km, respectively. If true, it is possible that the same projectile that delivered most of the Moon's HSE may have also have provided it with water. The Moon's interior was once thought to be largely dry, with bulk water estimates of less than 1 part per billion (ppb). New sample measurements, however, suggest the water content in the lunar mantle is between 200 and several thousand ppb. Assuming that our inferred D = 250-300 km lunar projectile could reach and mix itself into a spherical shell that is 100 to 500 km deep within the Moon, and that the projectile had a minimum bulk water content of 0.05-0.2 wt% (i.e., conservative values similar to those measured from “dry rocks” like ordinary and enstatite chondrites), we estimate that 400-3000 ppb water could be delivered to the lunar interior by late accretion. This finding could help sidestep a difficult problem, namely explaining how the water in the lunar mantle could migrate from a “wet” primordial Earth to a growing Moon through a very hot and largely vaporized protolunar disk.

Highly siderophile element and 182W evidence for a partial late veneer in the source of 3.8 Ga rocks from Isua, Greenland

NASA Astrophysics Data System (ADS)

Dale, Christopher W.; Kruijer, Thomas S.; Burton, Kevin W.

2017-01-01

The higher-than-expected concentrations of highly siderophile elements (HSE) in Earth's mantle most likely indicate that Earth received a small amount of late accreted mass after core formation had ceased, known as the 'late veneer'. Small 182W excesses in the Moon and in some Archaean rocks - such as the source of 3.8 billion-year-old Isua magmatics - also appear consistent with the late veneer hypothesis, with a lower proportion received. However, 182W anomalies can also relate to other processes, including early mantle differentiation. To better assess the origin of these W isotope anomalies - and specifically whether they relate to the late veneer - we have determined the HSE abundances and 182W compositions of a suite of mafic to ultramafic rocks from Isua, from which we estimate HSE abundances in the source mantle and ultimately constrain the 182W composition of the pre-late veneer mantle. Our data suggest that the Isua source mantle had HSE abundances at around 50-65% of the present-day mantle, consistent with partial, but not complete, isolation from the late veneer. These data also indicate that at least part of the late veneer had been added and mixed into the mantle at the time the Isua source formed, prior to 3.8 Ga. For the same Isua samples we obtained a 13 ± 4 ppm182W excess, compared to the modern terrestrial mantle, in excellent agreement with previous data. Using combined 182W and HSE data we show that the Moon, Isua, and the present-day bulk silicate Earth (BSE) produce a well-defined co-variation between 182W composition and the mass fraction of late-accreted mass, as inferred from HSE abundances. This co-variation is consistent with the calculated effects of various late accretion compositions on the HSE and 182W signatures of Earth's mantle. The empirical relationship, therefore, implies that the Moon, Isua source and BSE received increasing proportions of late-accreted mass, supporting the idea of disproportional late accretion to the Earth and Moon, and consistent with the interpretation that the lunar 182W value of 27 ± 4 ppm represents the composition of Earth's mantle before the late veneer was added. In this case, the Isua source can represent ambient mantle after the giant moon-forming impact, into which only a part of Earth's full late veneer was mixed, rather than an isotopically distinct mantle domain produced by early differentiation, which would probably require survival through the giant Moon-forming impact.

Highly siderophile elements were stripped from Earth’s mantle by iron sulfide segregation

NASA Astrophysics Data System (ADS)

Rubie, David C.; Laurenz, Vera; Jacobson, Seth A.; Morbidelli, Alessandro; Palme, Herbert; Vogel, Antje K.; Frost, Daniel J.

2016-09-01

Highly siderophile elements (HSEs) are strongly depleted in the bulk silicate Earth (BSE) but are present in near-chondritic relative abundances. The conventional explanation is that the HSEs were stripped from the mantle by the segregation of metal during core formation but were added back in near-chondritic proportions by late accretion, after core formation had ceased. Here we show that metal-silicate equilibration and segregation during Earth’s core formation actually increased HSE mantle concentrations because HSE partition coefficients are relatively low at the high pressures of core formation within Earth. The pervasive exsolution and segregation of iron sulfide liquid from silicate liquid (the “Hadean matte”) stripped magma oceans of HSEs during cooling and crystallization, before late accretion, and resulted in slightly suprachondritic palladium/iridium and ruthenium/iridium ratios.

Regulation of human heme oxygenase-1 gene expression under thermal stress.

PubMed

Okinaga, S; Takahashi, K; Takeda, K; Yoshizawa, M; Fujita, H; Sasaki, H; Shibahara, S

1996-06-15

Heme oxygenase-1 is an essential enzyme in heme catabolism, and its human gene promoter contains a putative heat shock element (HHO-HSE). This study was designed to analyze the regulation of human heme oxygenase-1 gene expression under thermal stress. The amounts of heme oxygenase-1 protein were not increased by heat shock (incubation at 42 degrees C) in human alveolar macrophages and in a human erythroblastic cell line, YN-1-0-A, whereas heat shock protein 70 (HSP70) was noticeably induced. However, heat shock factor does bind in vitro to HHO-HSE and the synthetic HHO-HSE by itself is sufficient to confer the increase in the transient expression of a reporter gene upon heat shock. The deletion of the sequence, located downstream from HHO-HSE, resulted in the activation of a reporter gene by heat shock. These results suggest that HHO-HSE is potentially functional but is repressed in vivo. Interestingly, heat shock abolished the remarkable increase in the levels of heme oxygenase-1 mRNA in YN-1-0-A cells treated with hemin or cadmium, in which HSP70 mRNA was noticeably induced. Furthermore, transient expression assays showed that heat shock inhibits the cadmium-mediated activation of the heme oxygenase-1 promoter, whereas the HSP70 gene promoter was activated upon heat shock. Such regulation of heme oxygenase-1 under thermal stress may be of physiologic significance in erythroid cells.

Activation of transcriptional activity of HSE by a novel mouse zinc finger protein ZNFD specifically expressed in testis.

PubMed

Xu, Fengqin; Wang, Weiping; Lei, Chen; Liu, Qingmei; Qiu, Hao; Muraleedharan, Vinaydhar; Zhou, Bin; Cheng, Hongxia; Huang, Zhongkai; Xu, Weian; Li, Bichun; Wang, Minghua

2012-04-01

Zinc finger proteins (ZFPs) that contain multiple cysteine and/or histidine residues perform important roles in various cellular functions, including transcriptional regulation, cell proliferation, differentiation, and apoptosis. The Cys-Cys-His-His (C(2)H(2)) type of ZFPs are the well-defined members of this super family and are the largest and most complex proteins in eukaryotic genomes. In this study, we identified a novel C(2)H(2) type of zinc finger gene ZNFD from mice which has a 1,002 bp open reading frame and encodes a protein with 333 amino acid residues. The predicted 37.4 kDa protein contains a C(2)H(2) zinc finger domain. ZNFD gene is located on chromosome 18qD1. RT-PCR analysis revealed that the ZNFD gene was specifically expressed in mouse testis but not in other tissues. Subcellular localization analysis demonstrated that ZNFD was localized in the nucleus. Reporter gene assays showed that overexpression of ZNFD in the COS7 cells activates the transcriptional activities of heat shock element (HSE). Overall, these results suggest that ZNFD is a member of the zinc finger transcription factor family and it participates in the transcriptional regulation of HSE. Many heat shock proteins regulated by HSE are involved in testicular development. Therefore, our results suggest that ZNFD may probably participate in the development of mouse testis and function as a transcription activator in HSE-mediated gene expression and signaling pathways.

Heterogeneous Delivery of Silicate and Metal to the Earth via Large Planetesimals

NASA Astrophysics Data System (ADS)

Marchi, S.; Canup, R. M.; Walker, R. J.

2017-12-01

Earth's mantle abundances of at least some highly siderophile elements, (HSE; Re, Os, Ir, Ru, Pt, Rh, Pd, and Au), are much higher than would result from metal-silicate equilibration during terrestrial core formation, and can be better explained as a result of late accretion of a minimum of 0.5% Earth's masses after core formation was complete. Traditional models assume that HSEs delivered by late projectiles completely mixed and chemically equilibrated with the Earth's mantle. This appears likely for undifferentiated, well-mixed projectiles, or for relatively small, differentiated projectiles. However several arguments suggest that late projectiles may have been large (> 1500 km in diameter) and differentiated, and in this case, portions of the projectile's core may merge with the Earth's core, rather than being mixed into the Earth's mantle. We investigate projectile mixing with a suite of SPH simulations of differentiated planetesimal colliding with the Earth. A range of outcomes emerge from our simulations suggesting that for large impactors (>1500 km), the delivery of HSE to the Earth's mantle may be disproportionate with the overall delivery of mass. For impacts with impact angles < 45° , between ˜ 20% to 80% of the impactor's core may merge directly with the Earth's core; while for impact angle > 60°, most of the impactor core escapes for moderate impact speeds. An implication is that the late accreted mass inferred from terrestrial HSE abundances may be a substantial underestimate, by a factor 2-5. In addition, partial mixing of projectiles result in an enrichment in mantle vs core material delivered to the bulk silicate Earth, implying substantial compositional variations in the accreted mass. Such variations could produce initially localized domains in Earth's mantle with distinct, mass independent isotopic signatures, given the isotopic variability resulting from nucleosynthetic heterogeneities among genetically diverse meteorites. In general we find that larger, low angle collisions would be more likely to produce initial mantle domains of anomalous composition material. We discuss the implications of these findings in the light of isotopic anomalies (e.g. W) in ancient terrestrial rocks.

Partitioning of Ru, Rh, Pd, Re, Ir and Pt between liquid metal and silicate at high pressures and high temperatures - Implications for the origin of highly siderophile element concentrations in the Earth's mantle

NASA Astrophysics Data System (ADS)

Mann, Ute; Frost, Daniel J.; Rubie, David C.; Becker, Harry; Audétat, Andreas

2012-05-01

The apparent overabundance of the highly siderophile elements (HSEs: Pt-group elements, Re and Au) in the mantles of Earth, Moon and Mars has not been satisfactorily explained. Although late accretion of a chondritic component seems to provide the most plausible explanation, metal-silicate equilibration in a magma ocean cannot be ruled out due to a lack of HSE partitioning data suitable for extrapolations to the relevant high pressure and high temperature conditions. We provide a new data set of partition coefficients simultaneously determined for Ru, Rh, Pd, Re, Ir and Pt over a range of 3.5-18 GPa and 2423-2773 K. In multianvil experiments, molten peridotite was equilibrated in MgO single crystal capsules with liquid Fe-alloy that contained bulk HSE concentrations of 53.2-98.9 wt% (XFe = 0.03-0.67) such that oxygen fugacities of IW - 1.5 to IW + 1.6 (i.e. logarithmic units relative to the iron-wüstite buffer) were established at run conditions. To analyse trace concentrations of the HSEs in the silicate melt with LA-ICP-MS, two silicate glass standards (1-119 ppm Ru, Rh, Pd, Re, Ir, Pt) were produced and evaluated for this study. Using an asymmetric regular solution model we have corrected experimental partition coefficients to account for the differences between HSE metal activities in the multicomponent Fe-alloys and infinite dilution. Based on the experimental data, the P and T dependence of the partition coefficients (D) was parameterized. The partition coefficients of all HSEs studied decrease with increasing pressure and to a greater extent with increasing temperature. Except for Pt, the decrease with pressure is stronger below ˜6 GPa and much weaker in the range 6-18 GPa. This change might result from pressure induced coordination changes in the silicate liquid. Extrapolating the D values over a large range of potential P-T conditions in a terrestrial magma ocean (peridotite liquidus at P ⩽ 60-80 GPa) we conclude that the P-T-induced decrease of D would not have been sufficient to explain HSE mantle abundances by metal-silicate equilibration at a common set of P-T-oxygen fugacity conditions. Therefore, the mantle concentrations of most HSEs cannot have been established during core formation. The comparatively less siderophile Pd might have been partly retained in the magma ocean if effective equilibration pressures reached 35-50 GPa. To a much smaller extent this could also apply to Pt and Rh providing that equilibration pressures reached ⩾60 GPa in the late stage of accretion. With most of the HSE partition coefficients at 60 GPa still differing by 0.5-3 orders of magnitude, metal-silicate equilibration alone cannot have produced the observed near-chondritic HSE abundances of the mantles of the Earth as well as of the Moon or Mars. Our results show that an additional process, such as the accretion of a late veneer composed of some type of chondritic material, was required. The results, therefore, support recent hybrid models, which propose that the observed HSE signatures are a combined result of both metal-silicate partitioning as well as an overprint by late accretion.

Can we differentiate between herpes simplex encephalitis and Japanese encephalitis?

PubMed

Kalita, Jayantee; Misra, Usha Kant; Mani, Vinita Elizabeth; Bhoi, Sanjeev Kumar

2016-07-15

Herpes simplex encephalitis (HSE) occurs without regional and seasonal predilections. HSE is important to differentiate from arboviral encephalitis in endemic areas because of therapeutic potential of HSE. This study evaluates clinical features, MRI and laboratory findings which may help in differentiating HSE from Japanese encephalitis (JE). Confirmed patients with JE and HSE in last 10years were included. The presenting clinical symptoms including demographic information, seizure, behavioral abnormality, focal weakness and movement disorders were noted. Cranial MRI was done and location and nature of signal alteration were noted. Electroencephalography (EEG), cerebrospinal fluid (CSF), blood counts and serum chemistry were done. Outcome was measured by modified Rankin Scale (mRS). Death, functional outcome and neurological sequelae were noted at 3, 6 and 12months follow up, and compared between HSE and JE. Outcome was categorized as poor (mRS;>2) and good (mRS≤2). 97 patients with JE and 40 HSE were included. JE patients were younger than HSE and occurred in post monsoon period whereas HSE occurred throughout the year. Seizure (86% vs 40%) and behavioral abnormality (48% vs 10%) were commoner in HSE; whereas movement disorders (76% vs 0%) and focal reflex loss (42% vs 10%) were commoner in JE. CSF findings and laboratory parameters were similar in both the groups. Thalamic involvement in JE and temporal involvement in HSE were specific markers of respective encephalitis. Delta slowing on EEG was more frequent in JE than HSE. 20% JE and 30% HSE died in the hospital, and at 1year follow up JE patients showed better outcome compared to HSE (48% vs 24%). Memory loss (72% vs 22%) was the predominant sequelae in HSE. Seizure and behavioral abnormality are common features in HSE whereas focal reflex loss is commoner in JE. In a patient with acute encephalitis, thalamic lesion suggests JE and temporal lobe involvement HSE. Long term outcome in JE is better compared to HSE. Copyright © 2016 Elsevier B.V. All rights reserved.

Interpreting HSE Contents of Planetary Basalts: The Importance of Sulfide Saturation and Under-Saturation

NASA Technical Reports Server (NTRS)

Righter, K.

2000-01-01

Highly siderophile elements provide important constraints on planetary differentiation due to their siderophile behavior. Their interpretation in terms of planetary differentiation models has so far overlooked the importance of sulfide saturation and under-saturation.

Late Accreted Material on the Lunar Surface: Constraints from Highly Siderophile and Chalcophile Elements in Ancient Lunar Impactites

NASA Astrophysics Data System (ADS)

Gleißner, P.; Becker, H.

2017-05-01

Abundances of HSE, Te, Se, and S in ancient lunar impactites constrain accretion of differentiated and primitive material (including carbonaceous chondrite-like material) and variable mixing of their compositions on the lunar surface.

Transferable tight binding model for strained group IV and III-V heterostructures

NASA Astrophysics Data System (ADS)

Tan, Yaohua; Povolotskyi, Micheal; Kubis, Tillmann; Boykin, Timothy; Klimeck, Gerhard

Modern semiconductor devices have reached critical device dimensions in the range of several nanometers. For reliable prediction of device performance, it is critical to have a numerical efficient model that are transferable to material interfaces. In this work, we present an empirical tight binding (ETB) model with transferable parameters for strained IV and III-V group semiconductors. The ETB model is numerically highly efficient as it make use of an orthogonal sp3d5s* basis set with nearest neighbor inter-atomic interactions. The ETB parameters are generated from HSE06 hybrid functional calculations. Band structures of strained group IV and III-V materials by ETB model are in good agreement with corresponding HSE06 calculations. Furthermore, the ETB model is applied to strained superlattices which consist of group IV and III-V elements. The ETB model turns out to be transferable to nano-scale hetero-structure. The ETB band structures agree with the corresponding HSE06 results in the whole Brillouin zone. The ETB band gaps of superlattices with common cations or common anions have discrepancies within 0.05eV.

Solubility of Sulfur in Shergottitic Silicate Melts Up to 0.8 GPA: Implications for S Contents of Shergottites

NASA Technical Reports Server (NTRS)

Righter, K.; Pando, K.M.; Danielson, L.

2009-01-01

Shergottites have high S contents (1300 to 4600 ppm; [1]), but it is unclear if they are sulfide saturated or under-saturated. This issue has fundamental implications for determining the long term S budget of the martian surface and atmosphere (from mantle degassing), as well as evolution of the highly siderophile elements (HSE) Au, Pd, Pt, Re, Rh, Ru, Ir, and Os, since concentrations of the latter are controlled by sulfide stability. Resolution of sulfide saturation depends upon temperature, pressure, oxygen fugacity (and FeO), and magma composition [2]. Expressions derived from experimental studies allow prediction of S contents, though so far they are not calibrated for shergottitic liquids [3-5]. We have carried out new experiments designed to test current S saturation models, and then show that existing calibrations are not suitable for high FeO and low Al2O3 compositions characteristic of shergottitic liquids. The new results show that existing models underpredict S contents of sulfide saturated shergottitic liquids by a factor of 2.

Ultrasoft pseudopotentials and Hubbard U values for rare-earth elements (Re=La-Lu) guided by HSE06 calculations

NASA Astrophysics Data System (ADS)

Topsakal, Mehmet; Umemoto, Koichiro; Wentzcovitch, Renata

2014-03-01

The lanthanide series of the periodic table comprises fifteen members ranging from La to Lu - the rare-earth (Re) elements. They exhibit unique (and mostly unexplored) chemical properties depending on the fillings of 4f-orbitals. Due to strong electronic correlation, 4f valence electrons are incorrectly described by standard DFT functionals. In order to cope with these inefficiencies, the DFT+U method is often employed where Hubbard-type U is introduced into the standard DFT. Another approach is to use hybrid functionals. Both improve the treatment of strongly correlated electrons. However, DFT+U suffers from ambiguity of U while hybrid functionals suffer from extremely demanding computational costs. Here we provide Vanderbilt type ultrasoft pseudopotentials for Re elements with suggested U values allowing efficient plane-wave calculations. Hubbard U values are determined according to HSE06 calculations on Re-nitrides (ReN). Generated pseudopotentials were further tested on some Re-cobaltite (Re-CoO3) perovskites. Alternative pseudopotentials with f-electrons kept frozen in the core of pseudopotential are also provided and possible outcomes are addressed. We believe that these new pseudopotentials with suggested U values will allow further studies on rare-earth materials.

[Update on Herpes Simplex Encephalitis].

PubMed

Kuroda, Hiroshi

2015-07-01

Herpes simplex encephalitis (HSE), which is caused by the herpes simplex virus (HSV), is a severe neuro-infectious disease characterized by high mortality and morbidity. We reviewed the pathomechanism, diagnosis, and treatment of HSE based on recent progress in the field. The highlighted mechanism of HSE in this review is immune-mediated tissue damage caused by host immunity. Major symptoms of HSE include psychiatric alteration, Klüver-Bucy syndrome, and amnesia, caused by frequent involvement of the limbic system. An important differential diagnosis of HSE is autoimmune limbic encephalitis, including anti-N-methyl-D-aspartate receptor encephalitis, and anti-voltage-gated K⁺ channel encephalitis. HSE is definitely diagnosed based on the detection of HSV-DNA by polymerase chain reaction and/or the detection of HSV-IgG antibody in the cerebrospinal fluid (CSF). Repeated CSF examinations are required for the accurate diagnosis of HSE. Acyclovir (ACV) plays a central role in the treatment of HSE, and its early initiation is essential for good outcome in patients with HSE. Acute administration of corticosteroids for HSE is controversial; a randomized, double-blind, placebo-controlled trial to investigate the efficacy of add-on corticosteroids to ACV is ongoing.

Hibiscus sabdariffa extract inhibits obesity and fat accumulation, and improves liver steatosis in humans.

PubMed

Chang, Hong-Chou; Peng, Chiung-Huei; Yeh, Da-Ming; Kao, Erl-Shyh; Wang, Chau-Jong

2014-04-01

Obesity is associated with a great diversity of diseases including non-alcoholic fatty liver disease. Our previous report suggested that Hibiscus sabdariffa extracts (HSE) had a metabolic-regulating and liver-protecting potential. In this study, we performed a clinical trial to further confirm the effect of HSE. Subjects with a BMI ≧ 27 and aged 18-65, were randomly divided into control (n = 17) and HSE-treated (n = 19) groups, respectively, for 12 weeks. Our data showed that consumption of HSE reduced body weight, BMI, body fat and the waist-to-hip ratio. Serum free fatty acid (FFA) was lowered by HSE. Anatomic changes revealed that HSE improved the illness of liver steatosis. Ingestion of HSE was well tolerated and there was no adverse effect during the trial. No alteration was found for serum α-amylase and lipase. The clinical effect should mainly be attributed to the polyphenols of HSE, since composition analysis showed that branched chain-amino acids, which is associated with obesity, is not obviously high. In conclusion, consumption of HSE reduced obesity, abdominal fat, serum FFA and improved liver steatosis. HSE could act as an adjuvant for preventing obesity and non-alcoholic fatty liver.

Mantle xenoliths from Central Vietnam: evidence for at least Meso-Proterozoic formation of the lithospheric mantle

NASA Astrophysics Data System (ADS)

Proßegger, Peter; Ntaflos, Theodoros; Ackerman, Lukáš; Hauzenberger, Christoph; Tran, Tuan Anh

2016-04-01

Intraplate Cenozoic basalts that are widely dispersed along the continental margin of East Asia belong to the Western Pacific "diffuse" igneous province. They consist mainly of alkali basalts, basanites,rarely nephelinites, which are mantle xenolith-bearing, potassic rocks and quartz tholeiites. The volcanism in this area has been attributed to the continental extension caused by the collision of India with Asia and by the subduction of the Pacific Ocean below Asia. We studied a suite of 24 mantle xenoliths from La Bang Lake, Dak Doa district and Bien Ho, Pleiku city in the Gia Province, Central Vietnam. They are predominantly spinel lherzolites (19) but spinel harburgites (3) and two garnet pyroxenites are present as well. The sizes of the xenoliths range from 5 to 40 cm in diameter with medium to coarse-grained protogranular textures. Whole rock major and trace element analyses display a wide range of compositions. The MgO concentration varies from 36.0 to 45.8 wt% whereas Al2O3 and CaO range from 0.63 to 4.36 wt% and from 0.52 to 4.21 wt% (with one sample having CaO of 6.63 wt%) respectively. Both CaO and Al2O3 positively correlate with MgO most likely indicating that the sampled rocks were derived from a common mantle source experienced variable degrees of partial melting. Mineral analyses show that the rock forming minerals are chemically homogeneous. The Fo contents of olivine vary between 89.2 and 91.2 and the Mg# of orthopyroxene and clinopyroxene range from 89 to 92 and 89 to 94 respectively. The range of Cr# for spinel is 0.06-0.26. Model calculations in both whole rock and clinopyroxenes show that lithospheric mantle underneath Central Vietnam experienced melt extractions that vary between 2-7, 12-15 and 20-30%. The majority of the primitive mantle-normalized whole rock and clinopyroxene REE patterns are parallel to each other indicating that clinopyroxene is the main repository of the trace elements. Clinopyroxenes are divided into two groups: group A with concave upwards REE and (La/Yb)N < 1 suggesting various degrees of melt extraction and group B with (La/Yb)N ranging between 1 and 10. The group B in a mantle normalized trace element diagram shows negative Pb and Sr anomalies compared to their neighbour elements, which together with the general absence of hydrous phases, suggest variable interaction with percolating silicate melt(s). The primitive-mantle normalized highly siderophile element (HSE) concentration pattern show almost no fractionation among Ir, Ru and Pt with only slight depletion in Os suggesting very limited effect of metasomatism on the HSE contents. On the other hand, most of the samples display clear Re addition from the percolating melts preventing calculation of reliable rhenium depletion ages (TRD). However, one sample with depleted Pd and Re signature yield TRD of 1.0 Ga which can be interpreted as a minimum SCLM stabilization age in this area. Mantle xenoliths from Central Vietnam range from fertile to depleted compositions partly affected by metasomatic silicate melts. Re-Os isotopic composition reveals a Meso-Proterozoic minimum stabilization age of the lithospheric mantle.

The importance of sulfur for the behavior of highly-siderophile elements during Earth's differentiation

NASA Astrophysics Data System (ADS)

Laurenz, Vera; Rubie, David C.; Frost, Daniel J.; Vogel, Antje K.

2016-12-01

The highly siderophile elements (HSEs) are widely used as geochemical tracers for Earth's accretion and core formation history. It is generally considered that core formation strongly depleted the Earth's mantle in HSEs, which were subsequently replenished by a chondritic late veneer. However, open questions remain regarding the origin of suprachondritic Ru/Ir and Pd/Ir ratios that are thought to be characteristic for the primitive upper mantle. In most core-formation models that address the behavior of the HSEs, light elements such as S entering the core have not been taken into account and high P-T experimental data for S-bearing compositions are scarce. Here we present a comprehensive experimental study to investigate the effect of increasing S concentration in the metal on HSE metal-silicate partitioning at 2473 K and 11 GPa. We show that the HSEs become less siderophile with increasing S concentrations in the metal, rendering core-forming metal less efficient in removing the HSEs from the mantle if S is present. Furthermore, we investigated the FeS sulfide-silicate partitioning of the HSEs as a function of pressure (7-21 GPa) and temperature (2373-2673 K). The sulfide-silicate partition coefficient for Pt increases strongly with P, whereas those for Pd, Ru and Ir all decrease. The combined effect is such that above ∼20 GPa Ru becomes less chalcophile than Pt, which is opposite to their behavior in the metal-silicate system where Ru is always more siderophile than Pt. The newly determined experimental results are used in a simple 2-stage core formation model that takes into account the effect of S on the behavior of the HSEs during core formation. Results of this model show that segregation of a sulfide liquid to the core from a mantle with substantial HSE concentrations plays a key role in reproducing Earth's mantle HSE abundances. As Ru and Pd are less chalcophile than Pt and Ir at high P-T, some Ru and Pd remain in the mantle after sulfide segregation. Addition of the late veneer then raised the concentrations of all HSE to their current levels. Suprachondritic Ru/Ir and Pd/Ir ratios of the mantle can thus be explained by a combination of sulfide segregation together with the addition of a late veneer without the need to invoke unknown chondritic material.

When do ego threats lead to self-regulation failure? Negative consequences of defensive high self-esteem.

PubMed

Lambird, Kathleen Hoffman; Mann, Traci

2006-09-01

High self-esteem (HSE) is increasingly recognized as heterogeneous. By measuring subtypes of HSE, the present research reevaluates the finding that HSE individuals show poor self-regulation following ego threat (Baumeister, Heatherton, & Tice, 1993). In Experiment 1, participants with HSE showed poor self-regulation after ego threat only if they also were defensive (high in self-presentation bias). In Experiment 2, two measures--self-presentation bias and implicit self-esteem--were used to subtype HSE individuals as defensive. Both operationalizations of defensive HSE predicted poor self-regulation after ego threat. The results indicate that (a) only defensive HSE individuals are prone to self-regulation failure following ego threat and (b) measures of self-presentation bias and implicit self-esteem can both be used to detect defensiveness.

Arabidopsis HEAT SHOCK TRANSCRIPTION FACTORA1b overexpression enhances water productivity, resistance to drought, and infection

PubMed Central

Richard, François; Bowden, Laura; Morison, James I.L.; Mullineaux, Philip M.

2013-01-01

Heat-stressed crops suffer dehydration, depressed growth, and a consequent decline in water productivity, which is the yield of harvestable product as a function of lifetime water consumption and is a trait associated with plant growth and development. Heat shock transcription factor (HSF) genes have been implicated not only in thermotolerance but also in plant growth and development, and therefore could influence water productivity. Here it is demonstrated that Arabidopsis thaliana plants with increased HSFA1b expression showed increased water productivity and harvest index under water-replete and water-limiting conditions. In non-stressed HSFA1b-overexpressing (HSFA1bOx) plants, 509 genes showed altered expression, and these genes were not over-represented for development-associated genes but were for response to biotic stress. This confirmed an additional role for HSFA1b in maintaining basal disease resistance, which was stress hormone independent but involved H2O2 signalling. Fifty-five of the 509 genes harbour a variant of the heat shock element (HSE) in their promoters, here named HSE1b. Chromatin immunoprecipitation-PCR confirmed binding of HSFA1b to HSE1b in vivo, including in seven transcription factor genes. One of these is MULTIPROTEIN BRIDGING FACTOR1c (MBF1c). Plants overexpressing MBF1c showed enhanced basal resistance but not water productivity, thus partially phenocopying HSFA1bOx plants. A comparison of genes responsive to HSFA1b and MBF1c overexpression revealed a common group, none of which harbours a HSE1b motif. From this example, it is suggested that HSFA1b directly regulates 55 HSE1b-containing genes, which control the remaining 454 genes, collectively accounting for the stress defence and developmental phenotypes of HSFA1bOx. PMID:23828547

The heparan sulfate-modifying enzyme glucuronyl C5-epimerase HSE-5 controls Caenorhabditis elegans Q neuroblast polarization during migration.

PubMed

Wang, Xiangming; Liu, Jianhong; Zhu, Zhiwen; Ou, Guangshuo

2015-03-15

Directional cell migration is fundamental for neural development, and extracellular factors are pivotal for this process. Heparan sulfate proteoglycans (HSPGs) that carry long chains of differentially modified sugar residues contribute to extracellular matrix; however, the functions of HSPG in guiding cell migration remain elusive. Here, we used the Caenorhabditis elegans mutant pool from the Million Mutation Project and isolated a mutant allele of the heparan sulfate-modifying enzyme glucuronyl C5-epimerase HSE-5. Loss-of-function of this enzyme resulted in defective Q neuroblast migration. We showed that hse-5 controlled Q cell migration in a cell non-autonomous manner. By performing live cell imaging in hse-5 mutant animals, we found that hse-5 controlled initial polarization during Q neuroblast migration. Furthermore, our genetic epistasis analysis demonstrated that lon-2 might act downstream of hse-5. Finally, rescue of the hse-5 mutant phenotype by expression of human and mouse hse-5 homologs suggested a conserved function for this gene in neural development. Taken together, our results indicated that proper HSPG modification in the extracellular matrix by HSE-5 is essential for neuroblast polarity during migration. Copyright © 2015 Elsevier Inc. All rights reserved.

Von Willebrand Factor Gene Variants Associate with Herpes simplex Encephalitis.

PubMed

Abdelmagid, Nada; Bereczky-Veress, Biborka; Atanur, Santosh; Musilová, Alena; Zídek, Václav; Saba, Laura; Warnecke, Andreas; Khademi, Mohsen; Studahl, Marie; Aurelius, Elisabeth; Hjalmarsson, Anders; Garcia-Diaz, Ana; Denis, Cécile V; Bergström, Tomas; Sköldenberg, Birgit; Kockum, Ingrid; Aitman, Timothy; Hübner, Norbert; Olsson, Tomas; Pravenec, Michal; Diez, Margarita

2016-01-01

Herpes simplex encephalitis (HSE) is a rare complication of Herpes simplex virus type-1 infection. It results in severe parenchymal damage in the brain. Although viral latency in neurons is very common in the population, it remains unclear why certain individuals develop HSE. Here we explore potential host genetic variants predisposing to HSE. In order to investigate this we used a rat HSE model comparing the HSE susceptible SHR (Spontaneously Hypertensive Rats) with the asymptomatic infection of BN (Brown Norway). Notably, both strains have HSV-1 spread to the CNS at four days after infection. A genome wide linkage analysis of 29 infected HXB/BXH RILs (recombinant inbred lines-generated from the prior two strains), displayed variable susceptibility to HSE enabling the definition of a significant QTL (quantitative trait locus) named Hse6 towards the end of chromosome 4 (160.89-174Mb) containing the Vwf (von Willebrand factor) gene. This was the only gene in the QTL with both cis-regulation in the brain and included several non-synonymous SNPs (single nucleotide polymorphism). Intriguingly, in human chromosome 12 several SNPs within the intronic region between exon 43 and 44 of the VWF gene were associated with human HSE pathogenesis. In particular, rs917859 is nominally associated with an odds ratio of 1.5 (95% CI 1.11-2.02; p-value = 0.008) after genotyping in 115 HSE cases and 428 controls. Although there are possibly several genetic and environmental factors involved in development of HSE, our study identifies variants of the VWF gene as candidates for susceptibility in experimental and human HSE.

Von Willebrand Factor Gene Variants Associate with Herpes simplex Encephalitis

PubMed Central

Atanur, Santosh; Musilová, Alena; Zídek, Václav; Saba, Laura; Warnecke, Andreas; Khademi, Mohsen; Studahl, Marie; Aurelius, Elisabeth; Hjalmarsson, Anders; Garcia-Diaz, Ana; Denis, Cécile V.; Bergström, Tomas; Sköldenberg, Birgit; Kockum, Ingrid; Aitman, Timothy; Hübner, Norbert; Olsson, Tomas; Pravenec, Michal; Diez, Margarita

2016-01-01

Herpes simplex encephalitis (HSE) is a rare complication of Herpes simplex virus type-1 infection. It results in severe parenchymal damage in the brain. Although viral latency in neurons is very common in the population, it remains unclear why certain individuals develop HSE. Here we explore potential host genetic variants predisposing to HSE. In order to investigate this we used a rat HSE model comparing the HSE susceptible SHR (Spontaneously Hypertensive Rats) with the asymptomatic infection of BN (Brown Norway). Notably, both strains have HSV-1 spread to the CNS at four days after infection. A genome wide linkage analysis of 29 infected HXB/BXH RILs (recombinant inbred lines—generated from the prior two strains), displayed variable susceptibility to HSE enabling the definition of a significant QTL (quantitative trait locus) named Hse6 towards the end of chromosome 4 (160.89–174Mb) containing the Vwf (von Willebrand factor) gene. This was the only gene in the QTL with both cis-regulation in the brain and included several non-synonymous SNPs (single nucleotide polymorphism). Intriguingly, in human chromosome 12 several SNPs within the intronic region between exon 43 and 44 of the VWF gene were associated with human HSE pathogenesis. In particular, rs917859 is nominally associated with an odds ratio of 1.5 (95% CI 1.11–2.02; p-value = 0.008) after genotyping in 115 HSE cases and 428 controls. Although there are possibly several genetic and environmental factors involved in development of HSE, our study identifies variants of the VWF gene as candidates for susceptibility in experimental and human HSE. PMID:27224245

Human Systems Engineering: A Learning Model Designed To Converge Education, Business, and Industry.

ERIC Educational Resources Information Center

Hanson, Karen L.

The Human Systems Engineering (HSE) Model was created to facilitate collaboration among education, business, and industry. It emphasized the role of leaders who converge with others to accomplish their goals while paying attention to the key elements that create successful partnerships. The partnership of XXsys Technologies, Inc., University of…

Crystal Field Effects and Siderophile Element Partitioning: Implications for Mars HSE Geochemistry

NASA Technical Reports Server (NTRS)

Jones, John H.; Malavergne, V.; Neal, C. R.

2007-01-01

Analyses of martian (SNC) meteorites indicate that Pt abundances do not vary much compared to other highly siderophile elements (HSE). Therefore, Jones et al. [1] inferred that D(Pt) during basalt petrogenesis was of order unity. This inference was at odds with previously published experiments that gave a D(sub ol/liq) for Pt of approx. 0.01 [2]. Because olivine is likely to be an important constituent of any reasonable martian mantle, the implication of these findings is that minor minerals must have D(Pt) much greater than 1, which seemed improbable. However, not only did the SNC evidence point to a D(sub ol/liq) approx. equal to 1, but so did plots of D(sub ol/liq) vs. ionic radius (Onuma diagram). The ionic radius of Pt(2+) suggested that D(sub ol/liq) for Pt was of order unity, in agreement with the inferences from SNC meteorites. New experiments have failed to detect measurable Pt in olivine, even at high oxygen fugacities [3]. Therefore, some other parameter, other than ionic charge and radius, must hold sway during olivine liquid partitioning of Pt.

Secondary overprinting of S-Se-Te signatures in the Earth's mantle: Implications for the Late Veneer

NASA Astrophysics Data System (ADS)

Koenig, S.; Luguet, A.; Lorand, J.; Pearson, D.

2013-12-01

Sulphur, Selenium and Tellurium are both chalcophile and highly siderophile elements (HSE) with near-chondritic ratios and absolute abundances in the terrestrial mantle that exceed those predicted by core-mantle differentiation[1]. These 'excess' HSE abundances have been attributed to addition of ca. 0.5% of chondrite-like material that hit the Earth in its accretionary stage between 4 to 3.8 billion years ago after core-mantle differentiation (Late Veneer[2]). Therefore, like other HSE, S, Se and Te are considered potential tracers for the composition of the Late Veneer, provided that their bulk silicate Earth abundances are properly constrained. In contrast to ca. 250 ppm S, Se and Te are ultra-trace elements in the terrestrial mantle. Like all HSE, they are furthermore controlled by base metal sulphides (BMS) and micrometric platinum group minerals (PGMs)[3]. This strong control exerted by the host mineralogy and petrology on the S-Se-Te systematics at both the micro-scale and the whole-rock scale makes detailed mineralogical and petrological studies of BMS and PGM a pre-requisite to fully understand and accurately interpret the whole-rock signatures. Here we combine in-situ sulphide data and detailed mineralogical observations with whole-rock S-Se-Te-HSE signatures of both lherzolites and harburgites from different geodynamic settings. We demonstrate that the near-chondritic Se and Te signature of 'fertile' mantle rocks (Se/Te ≈9×5) is not a primitive signature of the Earth's mantle, but rather reflects strong enrichment in metasomatic HSE host phases, which erased previous pristine signatures. Consequently, current attempts to identify a potential Late Veneer composition are seriously flawed because, neither refertilisation/metasomatism nor true melt depletion (e.g. harzburgitic residues) have been taken into account for the Primitive Upper Mantle composition estimate[4]. Our combined whole rock and in-situ sulphide data indicate a refertilisation trend towards sub-chondritic Se/Te ratios (i.e. Se/Te < 2). On the other hand, harzburgites that preserve depletion signatures show suprachondritic Se/Te ratios (< 31). Altogether this shows that metasomatic enrichment of mantle rocks may lead to a systematic bias and hence underestimation of the current Se/Te estimate of the primitive mantle. The metasomatic origin of the reported S, Se and Te ratios in peridotites that reflect the control of metasomatic BMS and PGMs[5;6] furthermore show that not all whole rock signatures in the Earth's mantle that scatter around near-chondritic values are primary and hence challenge the simple conception that these features may readily solve the long-standing conundrum of the Late Veneer composition. Refs: [1] Rose-Weston et al. (2009) GCA 73, 4598-4615; [2] Kimura et al. (1974) GCA 38, 683-701; [3] Lorand and Alard (2010) 67, 4137-4151; [4] Wang and Becker (2013) Nature 499, 328-331; [5] König et al. (2012) GCA 86, 354-366; [6] König et al. (2013, in press), EPSL.

Processes in Early Planetesimals: Evidence from Ureilite Meteorites

NASA Technical Reports Server (NTRS)

Mittlefehldt, David W.; Downes, H.

2007-01-01

Ureilites are primitive ultramafic achondrites composed largely of olivine and pigeonite, with minor augite, carbon, sulphide and metal. They represent very early material in the history of the Solar System and form a bridge between undifferentiated chondrites and fully differentiated asteroids. They show a mixture of chemical characteristics, some of which are considered to be nebula-derived (e.g. a negative correlation between Mg/Fe and Delta O-17 that resembles that of the ordinary chondrites but at lower Delta O-17 values) whereas others have been imposed by asteroidal differentiation. Carbon isotope data show a striking negative correlation of delta C-13 values with mg# in olivine. delta C-13 also correlates positively with Delta O-17, and therefore this isotopic variation was probably also nebula-derived. Thus, oxygen and carbon isotope compositions and Fe-Mg systematics of each monomict ureilite were established before differentiation processes began. Heated by decay of short-lived radioactive isotopes, the ureilite asteroid started to melt. Metal and sulphide would have melted first, forming a Fe-S eutectic liquid, which removed chalcophile elements and incompatible siderophile elements, and basaltic melts that removed Al, Ca and the LREE. Several elements show different abundances and/or correlations with Fo content in olivine, e.g. carbon shows a positive correlation in ferroan ureilites, and a weak or even negative correlation in more magnesian compositions. HSE such as Os and Ir also show different distributions, i.e. ureilites with Fo < 82 have very scattered Os and Ir concentrations, which reach high values, whereas ureilites with Fo > 82 tend to have much less scattered and overall lower Os and Ir abundances. A similar change in elemental behaviour is shown by the Fe-Mn relations in ureilitic olivines: those with Fo contents < 85 show a good negative correlation, whereas those with Fo > 85 show much greater scatter. This suggests that a major change affected the parent body at a time when melting had reached relatively magnesian bulk compositions. We consider that this event may have been a hit and run collision in which the ureilite parent body collided with a larger object. During the collision, the ureilite mantle broke up catastrophically but re-accreted in a jumbled state around the still-intact core. Mg-rich basaltic melts that were in the process of being formed at the time of break-up were retained in part as melt clasts that re-accreted to the regolith and are found in polymict ureilites.

Delays in initiation of acyclovir therapy in herpes simplex encephalitis.

PubMed

Hughes, Peter S; Jackson, Alan C

2012-09-01

Diagnosis of herpes simplex encephalitis (HSE) is based on clinical findings, MRI, and detection of herpes simplex virus (HSV) DNA in cerebrospinal fluid (CSF) using polymerase chain reaction amplification. Delays in starting treatment are associated with poorer clinical outcomes. We assessed the timing of initiation of acyclovir therapy in HSE. Inpatient databases from seven hospitals in Winnipeg, Manitoba were used to identify individuals diagnosed with encephalitis and HSE from 2004 to 2009. The time taken to initiate therapy with acyclovir and the reasons for delays were determined. Seventy-seven patients were identified; 69 (90%) received acyclovir; in the others a non-HSV infection was strongly suspected. Thirteen patients were subsequently confirmed to have HSE. Acyclovir was initiated a median of 21 hours (3-407) after presentation in encephalitis cases, and a median of 11 hours (3-118) in HSE. The most common reason for delay was a failure to consider HSE in the differential diagnosis, despite suggestive clinical features. Where therapy was delayed in HSE patients, the decision to begin acyclovir was prompted by transfer of the patient to a different service (55%), recommendations by consultants (18%), imaging results (18%), and CSF pleocytosis (9%). Delays in initiating acyclovir for HSE are common, and are most often due to a failure to consider HSE in a timely fashion on presentation. In order to improve patient outcomes, physicians should be more vigilant for HSE, and begin acyclovir therapy expeditiously on the basis of clinical suspicion rather than waiting for confirmatory tests.

Clinical efficacy and mechanism of bilayered living human skin equivalent (HSE) in treatment of diabetic foot ulcers.

PubMed

Brem, Harold; Young, Jan; Tomic-Canic, Marjana; Isaacs, Cary; Ehrlich, H Paul

2003-01-01

Bilayered living human skin equivalent (HSE) consists of cultured keratinocytes residing on the surface of a fibroblast-populated collagen lattice. Although HSE is FDA-approved for treatment of diabetic foot and venous stasis ulcers, its clinical efficacy remains limited, because the molecular mechanisms underlying its therapeutic effect are not fully understood. It is, therefore, often applied mistakenly as a skin graft. In this report, we delineate a mechanism of HSE biological effect and consequent optimal clinical use in accelerating closure of diabetic foot ulcers. HSE was grafted onto nude mice and the release of various growth factors was evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and immunochemistry. Clinical: HSE was grafted onto 11 consecutive patients with diabetes who had 13 non-ischemic foot ulcers and healing was measured as time to 100% closure (e.g., no drainage and 100% epithelialized). HSE cellular components were determined to express 15 different growth factors/cytokine genes known to promote wound healing. Histological evidence from the nude mice showed that the collagen component of HSE underwent remodeling within the first seven days of grafting. Clinical: All diabetic foot ulcers healed in 31.8 12.4 days. Local release of a unique combination of 15 growth factors expressed by HSE keratinocyte and fibroblast components generates closure of diabetic foot ulcers. HSE should be applied with the same surgical conditions for a skin graft (i.e., no cellulitis, no drainage, and negligible bacteria). We hypothesize that bilayered HSE generates its effect by way of the local synthesis and release of multiple growth factors in specific combination and concentration, which improves the impaired reparative process of chronic wounds.

Herpes simplex encephalitis (HSE) and the immunocompromised: a clinical and autopsy study of HSE in the settings of cancer and human immunodeficiency virus-type 1 infection.

PubMed

Schiff, D; Rosenblum, M K

1998-03-01

Although herpes simplex encephalitis (HSE) is not regarded as an opportunistic infection, the occurrence of HSE in immunocompromised patients has been documented and the suggestion made that unusual clinical and neuropathologic features characterize the disorder in this population. To further characterize HSE as it affects the immunodeficient, the authors reviewed the clinical and pathological findings in three immunocompromised patients with autopsy-proven HSE. Two patients had cancer (one with lymphoma and another with glioblastoma multiforme), one was known to be human immunodeficiency virus-type 1 (HIV-1)-seropositive and a second was suspected of harboring underlying HIV-1 infection. Two were receiving dexamethasone at onset of HSE. All had fever, mental status changes and new, focal neurological deficits or worsening of established deficits. Cerebrospinal fluid (CSF) pleocytosis was absent or minimal and head computerized tomographic (CT) scans, performed in all cases, were unrevealing. No patient was clinically suspected of having HSE, only one received acyclovir (for concurrent mucocutaneous herpes) and HSE played a major role in all deaths. Autopsy revealed an unusual form of HSE characterized by a noninflammatory, pseudoischemic histological presentation and the unexpected persistence of viral antigens in abundance despite survival beyond the clinical stage during which inflammatory responses usually peak and productive brain infection wanes. The incidence of HSE in the immunocompromised may be underestimated. Preexistent neurological disease, a noninflammatory CSF profile and negative CT scan may confound the diagnosis in this population, a typical clinical presentation notwithstanding. Increased clinical suspicion, the use of magnetic resonance imaging and polymerase chain reaction analysis of CSF for herpes simplex virus nucleic acid sequences may permit more rapid diagnosis and treatment. The absence of inflammatory infiltrates in some fatal cases of HSE suggests that an intact immune response is not requisite to the devastating neurological injury characteristic of this disorder.

Cerebrospinal fluid cyto-/chemokine profile during acute herpes simplex virus induced anti-N-methyl-d-aspartate receptor encephalitis and in chronic neurological sequelae.

PubMed

Kothur, Kavitha; Gill, Deepak; Wong, Melanie; Mohammad, Shekeeb S; Bandodkar, Sushil; Arbunckle, Susan; Wienholt, Louise; Dale, Russell C

2017-08-01

To examine the cytokine/chemokine profile of cerebrospinal fluid (CSF) during acute herpes simplex virus-induced N-methyl-d-aspartate receptor (NMDAR) autoimmunity and in chronic/relapsing post-herpes simplex virus encephalitis (HSE) neurological syndromes. We measured longitudinal serial CSF cyto-/chemokines (n=34) and a glial marker (calcium-binding astroglial protein, S100B) in one patient during acute HSE and subsequent anti-NMDAR encephalitis, and compared the results with those from two patients with anti-NMDAR encephalitis without preceding HSE. We also compared cyto-/chemokines in cross-sectional CSF samples from three children with previous HSE who had ongoing chronic or relapsing neurological symptoms (2yr 9 mo-16y after HSE) with those in a group of children having non-inflammatory neurological conditions (n=20). Acute HSE showed elevation of a broad range of all T-helper-subset-related cyto-/chemokines and S100B whereas the post-HSE anti-NMDAR encephalitis phase showed persistent elevation of two of five T-helper-1 (chemokine [C-X-C motif] ligand 9 [CXCL9], CXCL10), three of five predominantly B-cell (CXCL13, CCL19, a proliferation-inducing ligand [APRIL])-mediated cyto-/chemokines, and interferon-α. The post-HSE anti-NMDAR encephalitis inflammatory response was more pronounced than anti-NMDAR encephalitis. All three chronic post-HSE cases showed persistent elevation of CXCL9, CXCL10, and interferon-α, and there was histopathological evidence of chronic lymphocytic inflammation in one biopsied case 7 years after HSE. Two of three chronic cases showed a modest response to immune therapy. HSE-induced anti-NMDAR encephalitis is a complex and pronounced inflammatory syndrome. There is persistent CSF upregulation of cyto-/chemokines in chronic or relapsing post-HSE neurological symptoms, which may be modifiable with immune therapy. The elevated cyto-/chemokines may be targets of monoclonal therapies. © 2017 Mac Keith Press.

The Troll HSE Risk Management System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiig, E.; Berthelsen, I.; Donovan, K.

1996-12-31

The Petroleum Act and Internal Control regulations in Norway lay down requirements for how HSE shall be Managed and documented. To comply with the Norwegian legislation the Troll Project has developed an HSE Risk Management System (RMS) structured around Hazards and Effects Management. The resulting quality, technical and operating integrity, and HSE performance are an endorsement of the power of RMS.

Genomic organization of the Neurospora crassa gsn gene: possible involvement of the STRE and HSE elements in the modulation of transcription during heat shock.

PubMed

Freitas, F Zanolli; Bertolini, M C

2004-12-01

Glycogen synthase, an enzyme involved in glycogen biosynthesis, is regulated by phosphorylation and by the allosteric ligand glucose-6-phosphate (G6P). In addition, enzyme levels can be regulated by changes in gene expression. We recently cloned a cDNA for glycogen synthase ( gsn) from Neurospora crassa, and showed that gsn transcription decreased when cells were exposed to heat shock (shifted from 30 degrees C to 45 degrees C). In order to understand the mechanisms that control gsn expression, we isolated the gene, including its 5' and 3' flanking regions, from the genome of N. crassa. An ORF of approximately 2.4 kb was identified, which is interrupted by four small introns (II-V). Intron I (482 bp) is located in the 5'UTR region. Three putative Transcription Initiation Sites (TISs) were mapped, one of which lies downstream of a canonical TATA-box sequence (5'-TGTATAAA-3'). Analysis of the 5'-flanking region revealed the presence of putative transcription factor-binding sites, including Heat Shock Elements (HSEs) and STress Responsive Elements (STREs). The possible involvement of these motifs in the negative regulation of gsn transcription was investigated using Electrophoretic Mobility Shift Assays (EMSA) with nuclear extracts of N. crassa mycelium obtained before and after heat shock, and DNA fragments encompassing HSE and STRE elements from the 5'-flanking region. While elements within the promoter region are involved in transcription under heat shock, elements in the 5'UTR intron may participate in transcription during vegetative growth. The results thus suggest that N. crassa possesses trans -acting elements that interact with the 5'-flanking region to regulate gsn transcription during heat shock and vegetative growth.

Unimolecular rearrangement of the simplest compound models with a selenium-oxygen, selenium-sulphur and selenium-selenium bond: SeXH and HSeXH (X = O,S,Se)

NASA Astrophysics Data System (ADS)

Viana, Rommel B.

2017-04-01

The aim of this study was to characterise the simplest compound models with a selenium-oxygen, selenium-sulphur and selenium-selenium bond as the SeXH and HSeXH isomers (X = O,S,Se). One of the main aspects of this investigation was to provide a description on the isomerisation pathways involving 2[H,Se,X] and 1[2H,Se,X] potential energy surfaces calculated at the CCSD(T)/CBS//MP2/cc-pVTZ level. The energy difference was 13 kcal mol-1 between hydroxyselenide (SeOH) and oxoselenium (HSeO), while a gap of 3 kcal mol-1 was predicted between thiol-selenide (SeSH) and selenol-sulphide (HSeS). The SeOH→HSeO unimolecular rearrangement showed a barrier energy of 44.6 kcal mol-1, decreasing almost two times in sulphur and selenium analogous reactions. In addition, hydroxyselenide (HSeOH), thioselenenic acid (HSeSH) and diselane (HSeSeH) were the global minimum configurations in the ground state, while the energy differences among the other isomers were close to 30 kcal mol-1. The HSeXH→H2SeX and HSeXH→SeXH2 isomerisations showed barrier energies ranging from 40 to 65 kcal mol-1, while these reverse routes presented heights that were three times smaller. The kinetic rate constant of each 1,2-H shift reaction was performed here as well as an analysis of the selenium-chalcogen bonds using natural bond orbital and bond order index methodologies.

Effect of Hibiscus sabdariffa extract on high fat diet-induced obesity and liver damage in hamsters.

PubMed

Huang, To-Wei; Chang, Chia-Ling; Kao, Erl-Shyh; Lin, Jenq-Horng

2015-01-01

Obesity is a chronic metabolic disorder associated with an increase in adipogenesis and often accompanied with fatty liver disease. In this study, we investigated the anti-obesity effects of Hibiscus sabdariffa water extract (HSE) in vivo. Eight-weeks-old male mice were divided into six groups (n=8 per group) and were fed either normal feed, a high fat diet (HFD), HFD supplemented with different concentrations of HSE, or HFD supplemented with anthocyanin. After 10 weeks of feeding, all the blood and livers were collected for further analysis. Mesocricetus auratus hamster fed with a high-fat diet developed symptoms of obesity, as determined from their body weight change and from their plasma lipid levels. Meanwhile, HSE treatment reduced fat accumulation in the livers of hamsters fed with HFD in a concentration-dependent manner. Administration of HSE reduced the levels of liver cholesterol and triglycerides, which were elevated by HFD. Analysis of the effect of HSE on paraoxonase 1, an antioxidant liver enzyme, revealed that HSE potentially regulates lipid peroxides and protects organs from oxidation-associated damage. The markers of liver damage such as serum alanine aminotransferase and aspartate aminotransferase levels that were elevated by HFD were also reduced on HSE treatment. The effects of HSE were as effective as treatment with anthocyanin; therefore the anthocyanins present in the HSE may play a crucial role in the protection established against HFD-induced obesity. In conclusion HSE administration constitutes an effective and viable treatment strategy against the development and consequences of obesity.

Effect of Hibiscus sabdariffa extract on high fat diet–induced obesity and liver damage in hamsters

PubMed Central

Huang, To-Wei; Chang, Chia-Ling; Kao, Erl-Shyh; Lin, Jenq-Horng

2015-01-01

Background Obesity is a chronic metabolic disorder associated with an increase in adipogenesis and often accompanied with fatty liver disease. Objective In this study, we investigated the anti-obesity effects of Hibiscus sabdariffa water extract (HSE) in vivo. Method Eight-weeks-old male mice were divided into six groups (n=8 per group) and were fed either normal feed, a high fat diet (HFD), HFD supplemented with different concentrations of HSE, or HFD supplemented with anthocyanin. After 10 weeks of feeding, all the blood and livers were collected for further analysis. Results Mesocricetus auratus hamster fed with a high-fat diet developed symptoms of obesity, as determined from their body weight change and from their plasma lipid levels. Meanwhile, HSE treatment reduced fat accumulation in the livers of hamsters fed with HFD in a concentration-dependent manner. Administration of HSE reduced the levels of liver cholesterol and triglycerides, which were elevated by HFD. Analysis of the effect of HSE on paraoxonase 1, an antioxidant liver enzyme, revealed that HSE potentially regulates lipid peroxides and protects organs from oxidation-associated damage. The markers of liver damage such as serum alanine aminotransferase and aspartate aminotransferase levels that were elevated by HFD were also reduced on HSE treatment. The effects of HSE were as effective as treatment with anthocyanin; therefore the anthocyanins present in the HSE may play a crucial role in the protection established against HFD-induced obesity. Conclusions In conclusion HSE administration constitutes an effective and viable treatment strategy against the development and consequences of obesity. PMID:26475512

Late Influx: Evidence from Siderophile Elements in Terrestrial Peridotites and Lunar Breccias

NASA Technical Reports Server (NTRS)

Morgan, J. W.; Brandon, A. D.; Walker, R. J.; Horan, M. F.

2001-01-01

In terrestrial peridotites, Pd is sometimes enhanced relative to other PGE. This observation is taken to imply a "non-chondritic" HSE signature in the mantle. A similar pattern is seen in some Apollo 17 breccias suggesting it to be a primordial feature of late influx. Additional information is contained in the original extended abstract.

Incidence and mortality of herpes simplex encephalitis in Denmark: A nationwide registry-based cohort study.

PubMed

Jørgensen, Laura Krogh; Dalgaard, Lars Skov; Østergaard, Lars Jørgen; Nørgaard, Mette; Mogensen, Trine Hyrup

2017-01-01

We aimed to investigate the incidence and mortality of herpes simplex encephalitis (HSE) in a nationwide cohort. From the Danish National Patient Registry, we identified all adults hospitalised with a first-time diagnosis of HSE in Denmark during 2004-2014. The HSE diagnoses were verified using medical records and microbiological data. Patients were followed for mortality through the Danish Civil Registry System. We estimated age-standardised incidence rates of HSE and 30-day, 60-day, and 1-year cumulative mortality. Furthermore, we assessed whether calendar year, age, gender, level of comorbidity, virus type, and department type was associated with HSE mortality. We identified a total of 230 cases of HSE. Median age was 60.7 years (interquartile range: 49.3-71.6). The overall incidence rate was 4.64 cases per million population per year (95% confidence interval: 4.06-5.28). The cumulative mortality within 30 days, 60 days, and 1 year of the HSE admission was 8.3%, 11.3%, and 18.6%, respectively. Advanced age and presence of comorbidity were associated with increased 60-day and 1-year mortality. This nationwide study of verified HSE found a higher incidence than reported in previous nationwide studies. Presence of comorbidity was identified as a novel adverse prognostic factor. Mortality rates following HSE remain high. Copyright © 2016 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

The case for immunomodulatory approaches in treating HSV encephalitis

PubMed Central

Ramakrishna, Chandran; Openshaw, Harry; Cantin, Edouard M

2013-01-01

HSV encephalitis (HSE) is the most prevalent sporadic viral encephalitis. Although safe and effective antiviral therapies and greatly improved noninvasive diagnostic procedures have significantly improved outcomes, mortality (~20%) and debilitating neurological sequelae in survivors remain unacceptably high. An encouraging new development is that the focus is now shifting away from the virus exclusively, to include consideration of the host immune response to infection in the pathology underlying development of HSE. In this article, the authors discuss results from recent studies in experimental mouse models, as well as clinical reports that demonstrate a role for exaggerated host inflammatory responses in the brain in the development of HSE that is motivating researchers and clinicians to consider new therapeutic approaches for treating HSE. The authors also discuss results from a few studies that have shown that immunomodulatory drugs can be highly protective against HSE, which supports a role for deleterious host inflammatory responses in HSE. The impressive outcomes of some immunomodulatory approaches in mouse models of HSE emphasize the urgent need for clinical trials to rigorously evaluate combination antiviral and immunomodulatory therapy in comparison with standard antiviral therapy for treatment of HSE, and support for such an initiative is gaining momentum. PMID:23956785

Accurate Prediction of Inducible Transcription Factor Binding Intensities In Vivo

PubMed Central

Siepel, Adam; Lis, John T.

2012-01-01

DNA sequence and local chromatin landscape act jointly to determine transcription factor (TF) binding intensity profiles. To disentangle these influences, we developed an experimental approach, called protein/DNA binding followed by high-throughput sequencing (PB–seq), that allows the binding energy landscape to be characterized genome-wide in the absence of chromatin. We applied our methods to the Drosophila Heat Shock Factor (HSF), which inducibly binds a target DNA sequence element (HSE) following heat shock stress. PB–seq involves incubating sheared naked genomic DNA with recombinant HSF, partitioning the HSF–bound and HSF–free DNA, and then detecting HSF–bound DNA by high-throughput sequencing. We compared PB–seq binding profiles with ones observed in vivo by ChIP–seq and developed statistical models to predict the observed departures from idealized binding patterns based on covariates describing the local chromatin environment. We found that DNase I hypersensitivity and tetra-acetylation of H4 were the most influential covariates in predicting changes in HSF binding affinity. We also investigated the extent to which DNA accessibility, as measured by digital DNase I footprinting data, could be predicted from MNase–seq data and the ChIP–chip profiles for many histone modifications and TFs, and found GAGA element associated factor (GAF), tetra-acetylation of H4, and H4K16 acetylation to be the most predictive covariates. Lastly, we generated an unbiased model of HSF binding sequences, which revealed distinct biophysical properties of the HSF/HSE interaction and a previously unrecognized substructure within the HSE. These findings provide new insights into the interplay between the genomic sequence and the chromatin landscape in determining transcription factor binding intensity. PMID:22479205

Evaluation of holistic sexuality education: A European expert group consensus agreement.

PubMed

Ketting, Evert; Friele, Minou; Michielsen, Kristien

2016-01-01

Holistic sexuality education (HSE) is a new concept in sexuality education (SE). Since it differs from other types of SE in a number of important respects, strategies developed for the evaluation of the latter are not necessarily applicable to HSE. In this paper the authors provide a basis for discussion on how to evaluate HSE. First, the international literature on evaluation of SE in general was reviewed in terms of its applicability to HSE. Second, the European Expert Group on Sexuality Education extensively discussed the requirements of its evaluation and suggested appropriate indicators and methods for evaluating HSE. The European experience in SE is scarcely represented in the general evaluation literature. The majority of the literature focuses on impact and neglects programme and implementation evaluations. Furthermore, the current literature demonstrates that evaluation criteria predominantly focus on the public health impact, while there is not yet a consensus on sexual well-being criteria and aspects of positive sexuality, which are crucial parts of HSE. Finally, experimental designs are still considered the gold standard, yet several of the conditions for their use are not fulfilled in HSE. Realising that a new evaluation framework for HSE is needed, the European expert group initiated its development and agreed upon a number of indicators that provide a starting point for further discussion. Aside from the health impact, the quality of SE programmes and their implementation also deserve attention and should be evaluated. To be applicable to HSE, the evaluation criteria need to cover more than the typical public health aspects. Since they do not register long-term and multi-component characteristics, evaluation methods such as randomised controlled trials are not sufficiently suitable for HSE. The evaluation design should rely on a number of different information sources from mixed methods that are complemented and triangulated to build a plausible case for the effectiveness of SE in general and HSE in particular.

Herpes Simplex Encephalitis: an Update.

PubMed

Gnann, John W; Whitley, Richard J

2017-03-01

The goal of this review is to provide an update on current thinking regarding herpes simplex encephalitis (HSE), emphasizing new information about pathogenesis, diagnosis, and immune responses. Specific questions to be addressed are the following: (1) Is there a genetic predisposition to HSE? (2) What clinical approaches have the greatest impact on improving the long-term outcomes in patients with HSE? And (3) are there immune-mediated mechanisms that may account for relapsing HSE? Toll-like receptor 3 (TLR 3) plays an important role in innate immune responses, including generation of interferons. Multiple single-gene errors in TLR 3 interferon pathways have recently been described in children that result in increased susceptibility to HSE. Conversely, studies in both animal models and humans indicate that both cytolytic viral replication and immune-mediated responses (including cytotoxic T lymphocytes and immune mechanisms mediated by TLR 2) contribute to the pathology of HSV, suggesting possible new therapeutic approaches. In terms of treatment, data clearly indicate that a longer duration between onset of symptoms and initiation of effective antiviral therapy correlates directly with less favorable clinical outcome. Recurrent or relapsing HSE may occasionally occur, but recent observations indicate that many instances of "relapsing HSE", especially in children, are more often anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis triggered by the antecedent HSV infection. Innate immune responses are critical for defense against HSV; genetic defects in this system may predispose patients to HSE. During acute HSE, exuberant immune responses may contribute to the CNS pathology, suggesting that selective immunosuppressive therapy, coupled with potent antiviral drugs, may eventually play a role in the therapeutic management of HSV. While overall clinical outcomes of HSE remain suboptimal, the initiation of high-dose acyclovir therapy as early as possible in the course of the illness provides the best chance for a patient to survive with minimal neurologic damage. Distinguishing relapsing HSE from autoimmune anti-NMDAR antibody encephalitis is critically important because therapeutic approaches will be very different.

Ab initio assessment of Bi1-xRExCuOS (RE = La, Gd, Y, Lu) solid solutions as a semiconductor for photochemical water splitting.

PubMed

Lardhi, Sheikha; Curutchet, Antton; Cavallo, Luigi; Harb, Moussab; Le Bahers, Tangui

2017-05-17

The investigation of the BiCuOCh (Ch = S, Se and Te) semiconductor family for thermoelectric or photovoltaic materials is a topic of increasing research interest. These materials can also be considered for photochemical water splitting if one representative having a bandgap, E g , at around 2 eV can be developed. With this aim, we simulated the solid solutions Bi 1-x RE x CuOS (RE = Y, La, Gd and Lu) from pure BiCuOS (E g ∼ 1.1 eV) to pure RECuOS compositions (E g ∼ 2.9 eV) by DFT calculations based on the HSE06 range-separated hybrid functional with the inclusion of spin-orbit coupling. Starting from the thermodynamic stability of the solid solution, several properties were computed for each system including bandgaps, dielectric constants, effective masses and exciton binding energies. We discussed the variation of these properties based on the relative organization of Bi and RE atoms in their common sublattice to offer a physical understanding of the influence of the RE doping of BiCuOS. Some compositions were found to give appropriate properties for water splitting applications. Furthermore, we found that at low RE fractions the transport properties of BiCuOS are improved that can find applications beyond water splitting.

Committed HSE management Vs TQM: Is there any difference?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aitken, J.D.; McMath, C.R.; Lombardo, G.J.

1996-11-01

Safe performance of oilfield service operations at unfamiliar customer installations requires service personnel that are highly trained and motivated. When such operations are made in over sixty countries with an independent, multi-cultural work force, an additional level of difficulty in achieving an improved level of HSE (Health, Safety & Environment) performance is introduced. Recognizing these challenges, one company set out in 1989 to implement a comprehensive HSE management system suited to this environment. The system, described here, was launched with total commitment and participation of all levels of management and was designed to empower the work force rather than forcemore » them into compliance. This included a realignment of management priorities to give HSE a primary place along with other management responsibilities. One central theme of the system is a single standard applied to all HSE actions, throughout the world and at all levels of the Company. Thus, for example, all employees including all managers go through the same basic HSE training courses on a regular basis. After six years, a cultural change has taken place, along with a notable reduction in both accident frequency and severity, measured in terms of lost workdays. This reduction in lost workdays is an easily quantifiable cost saving which by far outweighs the total cost of the HSE system implementation. While the HSE management system was designed to specifically meet the needs of the company, the techniques used closely parallel those of Total Quality Management (TQM), which, in the last years, has gained momentum as a {open_quotes}new paradigm{close_quotes} in the HSE field. In this company`s experience, a common sense application of sound management to the HSE process has led to a TQM system.« less

Association of Constitutive Hyperphosphorylation of Hsf1p with a Defective Ethanol Stress Response in Saccharomyces cerevisiae Sake Yeast Strains

PubMed Central

Noguchi, Chiemi; Watanabe, Daisuke; Zhou, Yan; Akao, Takeshi

2012-01-01

Modern sake yeast strains, which produce high concentrations of ethanol, are unexpectedly sensitive to environmental stress during sake brewing. To reveal the underlying mechanism, we investigated a well-characterized yeast stress response mediated by a heat shock element (HSE) and heat shock transcription factor Hsf1p in Saccharomyces cerevisiae sake yeast. The HSE-lacZ activity of sake yeast during sake fermentation and under acute ethanol stress was severely impaired compared to that of laboratory yeast. Moreover, the Hsf1p of modern sake yeast was highly and constitutively hyperphosphorylated, irrespective of the extracellular stress. Since HSF1 allele replacement did not significantly affect the HSE-mediated ethanol stress response or Hsf1p phosphorylation patterns in either sake or laboratory yeast, the regulatory machinery of Hsf1p is presumed to function differently between these types of yeast. To identify phosphatases whose loss affected the control of Hsf1p, we screened a series of phosphatase gene deletion mutants in a laboratory strain background. Among the 29 mutants, a Δppt1 mutant exhibited constitutive hyperphosphorylation of Hsf1p, similarly to the modern sake yeast strains, which lack the entire PPT1 gene locus. We confirmed that the expression of laboratory yeast-derived functional PPT1 recovered the HSE-mediated stress response of sake yeast. In addition, deletion of PPT1 in laboratory yeast resulted in enhanced fermentation ability. Taken together, these data demonstrate that hyperphosphorylation of Hsf1p caused by loss of the PPT1 gene at least partly accounts for the defective stress response and high ethanol productivity of modern sake yeast strains. PMID:22057870

Association of constitutive hyperphosphorylation of Hsf1p with a defective ethanol stress response in Saccharomyces cerevisiae sake yeast strains.

PubMed

Noguchi, Chiemi; Watanabe, Daisuke; Zhou, Yan; Akao, Takeshi; Shimoi, Hitoshi

2012-01-01

Modern sake yeast strains, which produce high concentrations of ethanol, are unexpectedly sensitive to environmental stress during sake brewing. To reveal the underlying mechanism, we investigated a well-characterized yeast stress response mediated by a heat shock element (HSE) and heat shock transcription factor Hsf1p in Saccharomyces cerevisiae sake yeast. The HSE-lacZ activity of sake yeast during sake fermentation and under acute ethanol stress was severely impaired compared to that of laboratory yeast. Moreover, the Hsf1p of modern sake yeast was highly and constitutively hyperphosphorylated, irrespective of the extracellular stress. Since HSF1 allele replacement did not significantly affect the HSE-mediated ethanol stress response or Hsf1p phosphorylation patterns in either sake or laboratory yeast, the regulatory machinery of Hsf1p is presumed to function differently between these types of yeast. To identify phosphatases whose loss affected the control of Hsf1p, we screened a series of phosphatase gene deletion mutants in a laboratory strain background. Among the 29 mutants, a Δppt1 mutant exhibited constitutive hyperphosphorylation of Hsf1p, similarly to the modern sake yeast strains, which lack the entire PPT1 gene locus. We confirmed that the expression of laboratory yeast-derived functional PPT1 recovered the HSE-mediated stress response of sake yeast. In addition, deletion of PPT1 in laboratory yeast resulted in enhanced fermentation ability. Taken together, these data demonstrate that hyperphosphorylation of Hsf1p caused by loss of the PPT1 gene at least partly accounts for the defective stress response and high ethanol productivity of modern sake yeast strains.

Diagnosis of Herpes Simplex Encephalitis by ELISA Using Antipeptide Antibodies Against Type-Common Epitopes of Glycoprotein B of Herpes Simplex Viruses.

PubMed

Bhullar, Shradha S; Chandak, Nitin H; Baheti, Neeraj N; Purohit, Hemant J; Taori, Girdhar M; Daginawala, Hatim F; Kashyap, Rajpal S

2016-01-01

Herpes simplex encephalitis (HSE) represents one of the most severe infectious diseases of the central nervous system (CNS). As effective antiviral drugs are available, an early, rapid, and reliable diagnosis has become important. The objective of this article was to develop a sensitive ELISA protocol for herpes simplex viruses (HSV) antigen detection and quantitation by assessing the usefulness of antipeptide antibodies against potential peptides of HSV glycoprotein B (gB). A total of 180 cerebrospinal fluid (CSF) samples of HSE and non-HSE patients were analyzed using a panel of antipeptide antibodies against synthetic peptides of HSV glycoprotein gB. The cases of confirmed and suspected HSE showed 80% and 51% positivity for antipeptide against synthetic peptide QLHDLRF and 77% and 53% positivity for antipeptide against synthetic peptide MKALYPLTT, respectively for the detection of HSV antigen in CSF. The concentration of HSV antigen was found to be higher in confirmed HSE as compared to suspected HSE group and the viral load correlated well with antigen concentration obtained using the two antipeptides in CSF of confirmed HSE group. This is the first article describing the use of antibodies obtained against synthetic peptides derived from HSV in diagnostics of HSE using patients' CSF samples.

VALIDITY OF HYDROSTATIC EQUILIBRIUM IN GALAXY CLUSTERS FROM COSMOLOGICAL HYDRODYNAMICAL SIMULATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suto, Daichi; Suto, Yasushi; Kawahara, Hajime

2013-04-10

We examine the validity of the hydrostatic equilibrium (HSE) assumption for galaxy clusters using one of the highest-resolution cosmological hydrodynamical simulations. We define and evaluate several effective mass terms corresponding to the Euler equations of gas dynamics, and quantify the degree of the validity of HSE in terms of the mass estimate. We find that the mass estimated under the HSE assumption (the HSE mass) deviates from the true mass by up to {approx}30%. This level of departure from HSE is consistent with the previous claims, but our physical interpretation is rather different. We demonstrate that the inertial term inmore » the Euler equations makes a negligible contribution to the total mass, and the overall gravity of the cluster is balanced by the thermal gas pressure gradient and the gas acceleration term. Indeed, the deviation from the HSE mass is well explained by the acceleration term at almost all radii. We also clarify the confusion of previous work due to the inappropriate application of the Jeans equations in considering the validity of HSE from the gas dynamics extracted from cosmological hydrodynamical simulations.« less

Relationship between parent held child records for immunisations, parental recall and health service.

PubMed

Jessop, L; Lotya, J; Murrin, C; Fallon, U B; Kelleher, C C

2011-03-01

Parent held child records (PHCR) were introduced in Ireland in 2008. This study investigated the relationship between the PHCR, parental recall and regional Health Service Executive (HSE) records for immunisation uptake. It used the Lifeways cohort study of 1070 singleton children to compare immunisation data from PHCR at one year, parental recall at five years and information from the HSE. When compared to HSE records, full recording of primary immunisations in the PHCR was reported for 695 of 749 (92.8%) children. Parental recall was correct for 520 of 538 (96.7%) children. Of the 307 completed PHCRs, 207 (75.9%) agreed with the HSE records. Agreement between the three sources for primary immunisations was 74-93% but was not statistically significant. Agreement was 91% (p < 0.001) for measles, mumps and rubella (MMR) vaccines between parental recall and HSE records. PHCRs underestimated and parental recall overestimated immunisation status when compared with HSE records.

Synergi and E&P forum HSE management system helps companies improve HSE performance and reduce losses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grundt, H.J.

1996-12-31

This paper discusses the use of information on accidents and near-misses to improve HSE performance and reduce losses in Exploration and Production activities. Incidents are considered a result of management system failure. To avoid incidents and recurrence of incidents, companies should adopt an integrated HSE Management System and software especially designed for recording, analyzing and following up events. The E&P Forum has issued guidelines to support current company HSE Management systems and practices. Concurrently, the Synergi Project has been established to facilitate experience transfer and effective handling of incidents as part of an integrated HSE Management System. The paper describesmore » how important it is to learn from past mistakes, to have a management system which facilitates the implementation of the required corrective action, and that tools for improved loss control are available.« less

Draugen HSE-case - occupational health risk management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Glas, J.J.P.; Kjaer, E.

1996-12-31

The Draugen HSE-Case serves as a risk management tool. Originally, risk management included only major safety hazards to personnel, environment and assets. Work Environment risks such as ergonomics, psycho-social factors and exposure to chemicals and noise, was not given the same attention. The Draugen HSE-Case addresses this weakness and extends all work environment risks. In order to promote line responsibility and commitment, relevant personnel is involved in the Case development. {open_quotes}THESIS{degrees}, a software application, is used to systematize input and to generate reports. The Draugen HSE-case encompasses: HSE risk analyses related to specific activities; Control of risk related to workmore » environment; Established tolerability criteria; Risk reducing measures; Emergency contingency measures; and Requirements for Competence and Follow-up. The development of Draugen HSE-Case is a continuous process. It will serve to minimize the potential of occupational illnesses, raise general awareness, and make occupational health management more cost-effective.« less

Systematic review: work-related stress and the HSE management standards.

PubMed

Brookes, K; Limbert, C; Deacy, C; O'Reilly, A; Scott, S; Thirlaway, K

2013-10-01

The Health and Safety Executive (HSE) has defined six management standards representing aspects of work that, if poorly managed, are associated with lower levels of employee health and productivity, and increased sickness absence. The HSE indicator tool aims to measure organizations' performance in managing the primary stressors identified by the HSE management standards. The aims of the study are to explore how the HSE indicator tool has been implemented within organizations and to identify contexts in which the tool has been used, its psychometric properties and relationships with alternative measures of well-being and stress. Studies that matched specific criteria were included in the review. Abstracts were considered by two researchers to ensure a reliable process. Full texts were obtained when abstracts met the inclusion criteria. Thirteen papers were included in the review. Using factor analysis and measures of reliability, the studies suggest that the HSE indicator tool is a psychometrically sound measure. The tool has been used to measure work-related stress across different occupational groups, with a clear relationship between the HSE tool and alternative measures of well-being. Limitations of the tool and recommendations for future research are discussed. The HSE indicator tool is a psychometrically sound measure of organizational performance against the HSE management standards. As such it can provide a broad overview of sources of work-related stress within organizations. More research is required to explore the use of the tool in the design of interventions to reduce stress, and its use in different contexts and with different cultural and gender groups.

Identification of an immunodominant epitope in glycoproteins B and G of herpes simplex viruses (HSVs) using synthetic peptides as antigens in assay of antibodies to HSV in herpes simplex encephalitis patients.

PubMed

Bhullar, S S; Chandak, N H; Baheti, N N; Purohit, H J; Taori, G M; Daginawala, H F; Kashyap, R S

2014-01-01

Herpes simplex encephalitis (HSE) is a severe viral infection of the central nervous system (CNS). Assay of antibody response is widely used in diagnostics of HSE. The aim of this study was to identify an immunodominant epitope determining the antibody response to herpes simplex viruses (HSVs) in cerebrospinal fluid (CSF) of HSE patients. The synthetic peptides that resembled type-common as well as type-specific domains of glycoproteins B (gB) and G (gG) of these viruses were evaluated for binding with IgM and IgG antibodies in CSF samples from HSE and non-HSE patients in ELISA. The QLHDLRF peptide, derived from gB of HSV was found to be an immunodominant epitope in the IgM and IgG antibody response. The patients with confirmed and suspected HSE showed in ELISA against this peptide 26% and 23% positivities for IgM, 43% and 37% positivities for IgG and 17% and 15% for both IgM and IgG antibodies, respectively. The total positivities of 86% and 75% for both IgM and IgG antibodies were obtained in the patients with confirmed and suspected HSE, respectively. These results demonstrate that a synthetic peptide-based diagnostics of HSE can be an efficient and easily accessible alternative. This is the first report describing the use of synthetic peptides derived from HSVs in diagnostics of HSE using patientsʹ CSF samples.

Protective role of Hibiscus sabdariffa calyx extract against streptozotocin induced sperm damage in diabetic rats

PubMed Central

Idris, Muhd Hanis Md; Budin, Siti Balkis; Osman, Mohamad; Mohamed, Jamaludin

2012-01-01

Diabetes mellitus contributes to male sexual dysfunction and infertility by modulating oxidative damage. To date, a number of studies have demonstrated antioxidant properties of Hibiscus sabdariffa Linn. This study was designed to investigate the effects of H. sabdariffa UKMR-2 variety on sperm functioning of streptozotocin-induced diabetic rats. Male Sprague-Dawley rats were allotted into four groups, namely control group (C), H. sabdariffa extract (HSE) group, diabetes group (D) and diabetes plus HSE group (D+HSE). HSE (100 mg/ kg/body weight) was administered orally for 28 consecutive days. After 28-days of supplementation, the rats were sacrificed to obtain epididymal sperm. Administration of HSE significantly lowered the level of fasting blood glucose and increased plasma insulin level in D+HSE group as compared to D group (p<0.05). Sperm quality in the D+HSE group was improved with significantly higher sperm concentrations (p<0.05) and sperm motility (p<0.001) as well as lower percentage of sperm abnormality (p<0.05) as compared to the diabetic group. Plasma follicle-stimulating hormone (FSH) level was significantly elevated (p<0.05) in D+HSE group than in D group while no significant alteration in plasma testosterone and luteinizing hormone (LH) level were seen between groups. In conclusion, this study suggested that H. sabdariffa UKMR-2 variety has a potential protective role against diabetes-induced sperm damage. PMID:27847454

Protective role of Hibiscus sabdariffa calyx extract against streptozotocin induced sperm damage in diabetic rats.

PubMed

Idris, Muhd Hanis Md; Budin, Siti Balkis; Osman, Mohamad; Mohamed, Jamaludin

2012-01-01

Diabetes mellitus contributes to male sexual dysfunction and infertility by modulating oxidative damage. To date, a number of studies have demonstrated antioxidant properties of Hibiscus sabdariffa Linn. This study was designed to investigate the effects of H. sabdariffa UKMR-2 variety on sperm functioning of streptozotocin-induced diabetic rats. Male Sprague-Dawley rats were allotted into four groups, namely control group (C), H. sabdariffa extract (HSE) group, diabetes group (D) and diabetes plus HSE group (D+HSE). HSE (100 mg/ kg/body weight) was administered orally for 28 consecutive days. After 28-days of supplementation, the rats were sacrificed to obtain epididymal sperm. Administration of HSE significantly lowered the level of fasting blood glucose and increased plasma insulin level in D+HSE group as compared to D group (p<0.05). Sperm quality in the D+HSE group was improved with significantly higher sperm concentrations (p<0.05) and sperm motility (p<0.001) as well as lower percentage of sperm abnormality (p<0.05) as compared to the diabetic group. Plasma follicle-stimulating hormone (FSH) level was significantly elevated (p<0.05) in D+HSE group than in D group while no significant alteration in plasma testosterone and luteinizing hormone (LH) level were seen between groups. In conclusion, this study suggested that H. sabdariffa UKMR-2 variety has a potential protective role against diabetes-induced sperm damage.

HSE management standards and stress-related work outcomes.

PubMed

Kerr, Robert; McHugh, Marie; McCrory, Mark

2009-12-01

The UK Health and Safety Executive's (HSE) Management Standards (MS) approach has been developed to help organizations manage potential sources of work-related stress. Although there is general support for the assessment model adopted by this approach, to date, there has been no empirical investigation of the relationship between the actual MS (as measured by the final revised version of the HSE Indicator Tool) and stress-related work outcomes. To investigate the relationship between the HSE MS and the following stress-related work outcomes: 'job satisfaction', job-related anxiety and depression and errors/near misses. An anonymous cross-sectional questionnaire was distributed by either e-mail or post to all employees within a community-based Health and Social Services Trust. Respondents completed the HSE Indicator Tool, a job-related anxiety and depression scale, a job satisfaction scale and an aggregated measure of the number of errors/near misses witnessed. Associations between the HSE Indicator Tool responses and stress-related work outcomes were analysed with regression statistics. A total of 707 employees completed the questionnaire, representing a low response rate of 29%. Controlling for age, gender and contract type, the HSE MS (as measured by the HSE Indicator Tool) were positively associated with job satisfaction and negatively associated with 'job-related anxiety', 'job-related depression' and 'witnessed errors/near misses'. This study provides empirical evidence to support the use of the MS approach in tackling workplace stress.

Effects of RNA interference therapy against herpes simplex virus type 1 encephalitis.

PubMed

da Silva, Alexandre S; Raposo, Jéssica V; Pereira, Tiago C; Pinto, Marcelo A; de Paula, Vanessa S

2016-01-01

Herpetic encephalitis (HSE) is caused mainly by herpes simplex virus type 1 (HSV-1) with an annual incidence of 1-4 cases/million inhabitants. Currently, HSE treatment faces difficulties such as the use of antivirals with elevated toxicity, metabolic side effects and HSV-1 resistance. An alternative to antivirals is the use of small interfering RNA (siRNA) as a viral replication inhibitor. In this work, siRNA targeting the UL-39 region was evaluated for HSE treatment in vivo. BALB/c mice were inoculated with HSV-1 and treated with siRNA. The treatment was evaluated through kinetics of HSV-1 replication inhibition, number of siRNA doses administered and treatment with siRNA plus acyclovir. All groups were evaluated for signs of HSE, mortality and HSV-1 replication inhibition. The treated group of the kinetic experiment demonstrated a reduction of HSE signs and an HSV-1 replication inhibition of 43.6-99.9% in the brain and 53-98% in trigeminal ganglia (TG). Animals treated with one or two doses of siRNA had a prolonged survival time, reduced clinical signs of HSE and HSV-1 replication inhibition of 67.7% in brains and 85.7% in TG of animals treated with two doses of siRNA. Also, animals treated with siRNA plus acyclovir demonstrated reduced signs of HSE and mortality, as well as HSV-1 replication inhibition in the brain (83.2%) and TG (74.5%). These findings demonstrated that siRNA was capable of reducing HSE clinical signs, prolonging survival time and inhibiting HSV-1 replication in mice. Thus, siRNA can be a potential alternative to the standard HSE treatment especially to reduce clinical signs and extend survival time in vivo.

Re-Os Systematics and HSE Distribution in Tieschitz (H3.6): Two Isochrons for One Meteorite

NASA Technical Reports Server (NTRS)

Smoliar, M. I.; Horan, M. F.; Alexander, C. M. OD.; Walker, R. J.

2004-01-01

Tieschitz is an ordinary chondrite that displays some unique features. So called "white matrix" and "bleached chondrules" are found in only few chondrites, while in Tieschitz they are significant components. These phases have been the object of numerous studies, and are generally considered to be formed by secondary alteration or even redeposition. A Sm-Nd study of selected chondrules from Tieschitz yielded a surprisingly young apparent age of 2.0 Ga, which most likely reflects the time of the alteration process. This makes Tieschitz very interesting with respect to providing a record of a young alteration event.

The Calcitonin Receptor Gene Is a Candidate for Regulation of Susceptibility to Herpes simplex Type 1 Neuronal Infection Leading to Encephalitis in Rat

PubMed Central

Abdelmagid, Nada; Bereczky-Veress, Biborka; Guerreiro-Cacais, André Ortlieb; Bergman, Petra; Luhr, Katarina M.; Bergström, Tomas; Sköldenberg, Birgit; Piehl, Fredrik

2012-01-01

Herpes simplex encephalitis (HSE) is a fatal infection of the central nervous system (CNS) predominantly caused by Herpes simplex virus type 1. Factors regulating the susceptibility to HSE are still largely unknown. To identify host gene(s) regulating HSE susceptibility we performed a genome-wide linkage scan in an intercross between the susceptible DA and the resistant PVG rat. We found one major quantitative trait locus (QTL), Hse1, on rat chromosome 4 (confidence interval 24.3–31 Mb; LOD score 29.5) governing disease susceptibility. Fine mapping of Hse1 using recombinants, haplotype mapping and sequencing, as well as expression analysis of all genes in the interval identified the calcitonin receptor gene (Calcr) as the main candidate, which also is supported by functional studies. Thus, using unbiased genetic approach variability in Calcr was identified as potentially critical for infection and viral spread to the CNS and subsequent HSE development. PMID:22761571

Poly(aryl-ether-ether-ketone) as a Possible Metalized Film Capacitor Dielectric: Accurate Description of the Band Gap Through Ab Initio Calculation

DTIC Science & Technology

2014-12-01

from standard HSE06 hybrid functional with α = 0.25 and ω = 0.11 bohr–1 and b) from HSE with α = 0.093 and ω of 0.11 bohr–1...better agreement for the band gap value for future calculations, a systemic study was conducted for the (α, ω) parameter space of the HSE ...orthogonal). Future HSE calculations will be performed with the updated parameters. Fig. 7 Density of States of PEEK based on the optimized

Anti-inflammatory effects of a Houttuynia cordata supercritical extract

PubMed Central

Shin, Sunhee; Joo, Seong Soo; Jeon, Jeong Hee; Park, Dongsun; Jang, Min-Jung; Kim, Tae-Ook; Kim, Hyun-Kyu; Hwang, Bang Yeon; Kim, Ki-Yon

2010-01-01

Anti-inflammatory effects of Houttuynia cordata supercritical extract (HSE) were investigated in a carrageenan-air pouch model. HSE (200 mg/kg, oral) suppressed exudation and albumin leakage, as well as inflammatory cell infiltration. Dexamethasone (2 mg/kg, i.p.) only decreased exudation and cell infiltration, while indomethacin (2 mg/kg, i.p.) reduced exudate volume and albumin content. HSE lowered tumor-necrosis factor (TNF)-α and nitric oxide (NO), as well as prostaglandin E2 (PGE2). Dexamethasone only reduced TNF-α and NO, while indomethacin decreased TNF-α and PGE2. The suppressive activity of HSE on NO and PGE2 production was confirmed in RAW 264.7. These results demonstrate that HSE exerts anti-inflammatory effects by inhibiting both TNF-α-NO and cyclooxygenase II-PGE2 pathways. PMID:20706037

Health, safety and environment conditions in primary schools of Northern Iran.

PubMed

Behzadkolaee, Seyed Mohammad Asadi; Mirmohammadi, Seyed Taghi; Yazdani, Jamshid; Gorji, Ali Morad Heidari; Toosi, Ameneh; Rokni, Mohammad; Gorji, Mohammad Ali Heidari

2015-01-01

People spend a considerable part of their childhood time in the schools, a phase that coincides with their physical and mental growth. A healthy educational environment is vital to student's health and wellbeing. This study is a descriptive study conducted in 100 primary schools (both state and nonprofit schools) from Sari's Districts 1 and 2 in Iran. Sampling was performed by census and data were collected using the standard questionnaire by direct interview. Data were analyzed by Excel and SPSS software (Version 20.0. IBM Corp, Armonk), NY: IBM Corp using independent numerical T2 testing. Significant relationship was observed between the kind of schools (P = 0.045) and their locations (P = 0.024), however the health, safety and environment (HSE) ratings among boys only versus girls only schools were similar (P = 0.159). Interestingly private and nongovernment schools and primary schools from Sari's districts one had consistently higher HSE ratings. The differential and higher HSE ratings in primary schools run by Private organizations and primary schools from Sari's districts one could be due to manager's awareness and implementation of recommended HSE standards, schools neglecting and overlooking these standards had lower HSE ratings. It is necessary that schools with lower HSE ratings are made aware of the guidelines and necessary infrastructures allocated to improve their HSE ratings.

Antitumoral Effect of Hibiscus sabdariffa on Human Squamous Cell Carcinoma and Multiple Myeloma Cells.

PubMed

Malacrida, Alessio; Maggioni, Daniele; Cassetti, Arianna; Nicolini, Gabriella; Cavaletti, Guido; Miloso, Mariarosaria

2016-10-01

Cancer is a leading cause of death worldwide. Despite therapeutic improvements, some cancers are still untreatable. Recently there has been an increasing interest in the use of natural substances for cancer prevention and treatment. Hibiscus sabdariffa (HS) is a plant, belonging to Malvaceae family, widespread in South Asia and Central Africa. HS extract (HSE) used in folk medicine, gained researchers' interest thanks to its antioxidant, anti-inflammatory, and chemopreventive properties. In the present study, we initially assessed HSE effect on a panel of human tumor cell lines. Then we focused our study on the following that are most sensitive to HSE action cell lines: Multiple Myeloma (MM) cells (RPMI 8226) and Oral Squamous Cell Carcinoma (OSCC) cells (SCC-25). In both RPMI 8226 and SCC-25 cells, HSE impaired cell growth, exerted a reversible cytostatic effect, and reduced cell motility and invasiveness. We evaluated the involvement of MAPKs ERK1/2 and p38 in HSE effects by using specific inhibitors, U0126 and SB203580, respectively. For both SCC-25 and RPMI 8226, HSE cytostatic effect depends on p38 activation, whereas ERK1/2 modulation is crucial for cell motility and invasiveness. Our results suggest that HSE may be a potential therapeutic agent against MM and OSCC.

Asking about Sex in General Health Surveys: Comparing the Methods and Findings of the 2010 Health Survey for England with Those of the Third National Survey of Sexual Attitudes and Lifestyles.

PubMed

Prah, Philip; Johnson, Anne M; Nardone, Anthony; Clifton, Soazig; Mindell, Jennifer S; Copas, Andrew J; Robinson, Chloe; Craig, Rachel; Woodhall, Sarah C; Macdowall, Wendy; Fuller, Elizabeth; Erens, Bob; Sonnenberg, Pam; Wellings, Kaye; Mercer, Catherine H

2015-01-01

Including questions about sexual health in the annual Health Survey for England (HSE) provides opportunities for regular measurement of key public health indicators, augmenting Britain's decennial National Survey of Sexual Attitudes and Lifestyles (Natsal). However, contextual and methodological differences may limit comparability of the findings. We examine the extent of these differences between HSE 2010 and Natsal-3 and investigate their impact on parameter estimates. Complex survey analyses of data from men and women in the 2010 HSE (n = 2,782 men and 3,588 women) and Natsal-3 undertaken 2010-2012 (n = 4,882 men and 6,869 women) aged 16-69y and resident in England, both using probability sampling, compared their characteristics, the amount of non-response to, and estimates from, sexual health questions. Both surveys used self-completion for the sexual behaviour questions but this was via computer-assisted self-interview (CASI) in Natsal-3 and a pen-and-paper questionnaire in HSE 2010. The surveys achieved similar response rates, both around 60%, and demographic profiles largely consistent with the census, although HSE participants tended to be less educated, and reported worse general health, than Natsal-3 participants. Item non-response to the sexual health questions was typically higher in HSE 2010 (range: 9-18%) relative to Natsal-3 (all <5%). Prevalence estimates for sexual risk behaviours and STI-related indicators were generally slightly lower in HSE 2010 than Natsal-3. While a relatively high response to sexual health questions in HSE 2010 demonstrates the feasibility of asking such questions in a general health survey, differences with Natsal-3 do exist. These are likely due to the HSE's context as a general health survey and methodological limitations such as its current use of pen-and-paper questionnaires. Methodological developments to the HSE should be considered so that its data can be interpreted in combination with those from dedicated sexual health surveys, thus improving our ability to monitor trends in sexual health.

Performance management of the public healthcare services in Ireland: a review.

PubMed

Mesabbah, Mohammed; Arisha, Amr

2016-01-01

Performance Management (PM) processes have become a potent part of strategic and service quality decisions in healthcare organisations. In 2005, the management of public healthcare in Ireland was amalgamated into a single integrated management body, named the Health Service Executive (HSE). Since then, the HSE has come up with a range of strategies for healthcare developments and reforms, and has developed a PM system as part of its strategic planning. The purpose of this paper is to review the application of PM in the Irish Healthcare system, with a particular focus on Irish Hospitals and Emergency Services. An extensive review of relevant HSE's publications from 2005 to 2013 is conducted. Studies of the relevant literature related to the application of PM and of international best practices in healthcare performance systems are also presented. PM and performance measurement systems used by the HSE include many performance reports designed to monitor performance trends and strategic goals. Issues in the current PM system include inconsistency of measures and performance reporting, unclear strategy alignment, and deficiencies in reporting (e.g. feedback and corrective actions). Furthermore, PM processes have not been linked adequately into Irish public hospitals' management systems. The HSE delivers several services such as mental health, social inclusion, etc. This study focuses on the HSE's PM framework, with a particular interest in acute hospitals and emergency services. This is the first comprehensive review of Irish healthcare PM since the introduction of the HSE. A critical analysis of the HSE reports identifies the shortcomings in its current PM system.

Generic health/safety/environment cases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelland, A.N.; Primrose, M.; Pickles, J.C.

1996-12-31

A desire to implement HSE Management Systems including HSE Cases in all Shell companies operations prompted the development of a relational data base software package (THESIS) to provide a structured way of preparing an HSE Case. The software includes features which facilitate the management of {open_quotes}Keeping the Case Alive{close_quotes}, enabling the dissemination of tasks and hazard information to the workplace. During the software development it was recognized that a significant reduction could be made in the resources which would be required to prepare an HSE Case for each and every operation by the building of {open_quotes}Generic HSE Cases{close_quotes} addressing specificmore » activities which were repeated across the Company`s operations. This was recognized to be particularly valid for the smaller Single String Venture type of operations. The activities selected for the initial Generic HSE Case development include Land Drilling Operations, Land Seismic Acquisition, and Land Transport. To establish the Generic HSE Case, the THESIS data base is populated with data for a generic operation, identifying all the hazards and activities associated with that operation including all the associated controls, with established formats for the textual sections. In effect, the Generic Case defines the standards required for that type of operation. To generate an operation specific HSE Case, the Generic Case thereafter requires to be modified/adapted so that it represents the actual situation in the operation which it defines. This process includes itemization of all the operation specific details, and may involve the inclusion/deletion of any additional/existing activities or hazards together with their associated controls.« less

Innate immune response during herpes simplex virus encephalitis and development of immunomodulatory strategies.

PubMed

Piret, Jocelyne; Boivin, Guy

2015-09-01

Herpes simplex viruses are large double-stranded DNA viruses. These viruses have the ability to establish a lifelong latency in sensory ganglia and to invade and replicate in the CNS. Apart from relatively benign mucosal infections, HSV is responsible for severe illnesses including HSV encephalitis (HSE). HSE is the most common cause of sporadic, potentially fatal viral encephalitis in Western countries. If left untreated, the mortality rate associated with HSE is approximately 70%. Despite antiviral therapy, the mortality is still higher than 30%, and almost 60% of surviving individuals develop neurological sequelae. It is suggested that direct virus-related and indirect immune-mediated mechanisms contribute to the damages occurring in the CNS during HSE. In this manuscript, we describe the innate immune response to HSV, the development of HSE in mice knock-out for proteins of the innate immune system as well as inherited deficiencies in key components of the signaling pathways involved in the production of type I interferon that could predispose individuals to develop HSE. Finally, we review several immunomodulatory strategies aimed at modulating the innate immune response at a critical time after infection that were evaluated in mouse models and could be combined with antiviral therapy to improve the prognosis of HSE. In conclusion, the cerebral innate immune response that develops during HSE is a "double-edged sword" as it is critical to control viral replication in the brain early after infection, but, if left uncontrolled, may also result in an exaggerated inflammatory response that could be detrimental to the host. Copyright © 2015 John Wiley & Sons, Ltd.

Human Systems Engineering: A Leadership Model for Collaboration and Change.

ERIC Educational Resources Information Center

Clark, Karen L.

Human systems engineering (HSE) was created to introduce a new way of viewing collaboration. HSE emphasizes the role of leaders who welcome risk, commit to achieving positive change, and help others achieve change. The principles of HSE and its successful application to the collaborative process were illustrated through a case study representing a…

Different mechanisms are involved in the transcriptional activation by yeast heat shock transcription factor through two different types of heat shock elements.

PubMed

Hashikawa, Naoya; Yamamoto, Noritaka; Sakurai, Hiroshi

2007-04-06

The hydrophobic repeat is a conserved structural motif of eukaryotic heat shock transcription factor (HSF) that enables HSF to form a homotrimer. Homotrimeric HSF binds to heat shock elements (HSEs) consisting of three inverted repeats of the sequence nGAAn. Sequences consisting of four or more nGAAn units are bound cooperatively by two HSF trimers. We show that in Saccharomyces cerevisiae cells oligomerization-defective Hsf1 is not able to bind HSEs with three units and is not extensively phosphorylated in response to stress; it is therefore unable to activate genes containing this type of HSE. Several lines of evidence indicate that oligomerization is a prerequisite for stress-induced hyperphosphorylation of Hsf1. In contrast, oligomerization and hyperphosphorylation are not necessary for gene activation via HSEs with four units. Intragenic suppressor screening of oligomerization-defective hsf1 showed that an interface between adjacent DNA-binding domains is important for the binding of Hsf1 to the HSE. We suggest that Saccharomyces cerevisiae HSEs with different structures are regulated differently; HSEs with three units require Hsf1 to be both oligomerized and hyperphosphorylated, whereas HSEs with four or more units do not require either.

Anti-N-methyl-D-aspartate receptor encephalitis after Herpes simplex virus-associated encephalitis: an emerging disease with diagnosis and therapeutic challenges.

PubMed

Schein, Flora; Gagneux-Brunon, Amandine; Antoine, Jean-Christophe; Lavernhe, Sylvie; Pillet, Sylvie; Paul, Stéphane; Frésard, Anne; Boutet, Claire; Grange, Rémi; Cazorla, Céline; Lucht, Frédéric; Botelho-Nevers, Elisabeth

2017-08-01

Morbidity and mortality of Herpes simplex virus encephalitis (HSE) remain high. Relapses of neurological signs may occur after initial clinical improvement under acyclovir treatment. We report here a case of post-HSE anti-N-methyl-d-aspartate receptor-mediated encephalitis in an adult and perform a systematic search on PubMed to identify other cases in adults. We identified 11 previously published cases, to discuss diagnostic and therapeutic management. Symptoms in adults are often inappropriate behaviors, confusion and agitation. Diagnosis of anti-NMDA-R encephalitis after HSE is often delayed. Treatment consists in steroids, plasma exchange, and rituximab. Prognosis is often favorable. Anti-NMDA-R antibodies should be searched in cerebrospinal fluid of patients with unexpected evolution of HSE. This emerging entity reopens the hot debate about steroids in HSE.

CXCL11 production in cerebrospinal fluid distinguishes herpes simplex meningitis from herpes simplex encephalitis.

PubMed

Lind, Liza; Studahl, Marie; Persson Berg, Linn; Eriksson, Kristina

2017-07-10

The closely related herpes simplex viruses 1 and 2 can cause inflammations of the central nervous system (CNS), where type 1 most often manifest as encephalitis (HSE), and type 2 as meningitis (HSM). HSE is associated with severe neurological complications, while HSM is benign in adults. We proposed that studying the chemokine and cytokine production in cerebrospinal fluid (CSF) and serum could indicate why two closely related viruses exhibit different severity of their accompanied CNS inflammation. Secretion patterns of 30 chemokines and 10 cytokines in CSF of adult patients with acute HSE (n = 14) and HSM (n = 20) in the initial stage of disease were analyzed and compared to control subjects without viral central nervous system infections and to levels in serum. Most measured chemokines and cytokines increased in CSF of HSE and HSM patients. Overall, the CSF chemokine levels were higher in CSF of HSM patients compared to HSE patients. However, only five chemokines reached levels in the CSF that exceeded those in serum facilitating a positive CSF-serum chemokine gradient. Of these, CXCL8, CXCL9, and CXCL10 were present at high levels both in HSE and HSM whereas CXCL11 and CCL8 were present in HSM alone. Several chemokines were also elevated in serum of HSE patients but only one in HSM patients. No chemokine in- or efflux between CSF and serum was indicated as the levels of chemokines in CSF and serum did not correlate. We show that HSM is associated with a stronger and more diverse inflammatory response in the CNS compared to HSE in the initial stage of disease. The chemokine patterns were distinguished by the exclusive local CNS production of CXCL11 and CCL8 in HSM. Inflammation in HSM appears to be restricted to the CNS whereas HSE also was associated with systemic inflammation.

Theoretical study of the reactions of the hydroselenyl radical (HSe●) with the selenenic radical (HSeO●).

PubMed

Vega-Teijido, Mauricio Angel; Kieninger, Martina; Ventura, Oscar N

2017-12-05

The formation of selenium species in some biological processes involves the generation of ionic and radical intermediates such as RSe ● , RSe - , RSeO ● , and RSeO - , among others. We performed a theoretical study of the possible mechanisms for the reaction of the two simplest Se radicals-the hydroselenyl (HSe ● ) and selenenic (HSeO ● ) radicals, in which the possible products, intermediates, and transition-state structures were investigated. Density functional theory (DFT) was applied at the B3LYP/6-311++G(3df,3pd) level and the Ahlrichs Coulomb fitting basis sets were employed with an effective core potential (ECP) for both Se atoms. The same procedure was used to calculate the electronic density. All calculations were also performed using the M06-2X functional, which describes weaker bonds better than B3LYP does. In the reaction of interest, the so-called CR complex (HSe····SeOH) is formed initially. After passing through the transition state TS1, cis-HSeSeOH is obtained as a product. If a low barrier is then overcome (passing through the transition state TS32), the trans-HSeSeOH species is obtained. The CR complex can also rearrange into the intermediate INT after overcoming the barrier presented by the transition state TS2. Additionally, the decomposition of INT to H 2 O and 1 Se 2 is possible through another transition state. This reaction is not included in this study. We also observed a second possible route for the conversion of INT to one of the HSeSeOH species; this route occurs through two pathways (with transition states TS31 and TS32). A comparison of some of the results with those obtained for sulfur analogs along the same pathways is also presented in this work. Graphical abstract Electronic envelopes for HSeO ● and HSe ● radicals.

Validity of the coding for herpes simplex encephalitis in the Danish National Patient Registry.

PubMed

Jørgensen, Laura Krogh; Dalgaard, Lars Skov; Østergaard, Lars Jørgen; Andersen, Nanna Skaarup; Nørgaard, Mette; Mogensen, Trine Hyrup

2016-01-01

Large health care databases are a valuable source of infectious disease epidemiology if diagnoses are valid. The aim of this study was to investigate the accuracy of the recorded diagnosis coding of herpes simplex encephalitis (HSE) in the Danish National Patient Registry (DNPR). The DNPR was used to identify all hospitalized patients, aged ≥15 years, with a first-time diagnosis of HSE according to the International Classification of Diseases, tenth revision (ICD-10), from 2004 to 2014. To validate the coding of HSE, we collected data from the Danish Microbiology Database, from departments of clinical microbiology, and from patient medical records. Cases were classified as confirmed, probable, or no evidence of HSE. We estimated the positive predictive value (PPV) of the HSE diagnosis coding stratified by diagnosis type, study period, and department type. Furthermore, we estimated the proportion of HSE cases coded with nonspecific ICD-10 codes of viral encephalitis and also the sensitivity of the HSE diagnosis coding. We were able to validate 398 (94.3%) of the 422 HSE diagnoses identified via the DNPR. Hereof, 202 (50.8%) were classified as confirmed cases and 29 (7.3%) as probable cases providing an overall PPV of 58.0% (95% confidence interval [CI]: 53.0-62.9). For "Encephalitis due to herpes simplex virus" (ICD-10 code B00.4), the PPV was 56.6% (95% CI: 51.1-62.0). Similarly, the PPV for "Meningoencephalitis due to herpes simplex virus" (ICD-10 code B00.4A) was 56.8% (95% CI: 39.5-72.9). "Herpes viral encephalitis" (ICD-10 code G05.1E) had a PPV of 75.9% (95% CI: 56.5-89.7), thereby representing the highest PPV. The estimated sensitivity was 95.5%. The PPVs of the ICD-10 diagnosis coding for adult HSE in the DNPR were relatively low. Hence, the DNPR should be used with caution when studying patients with encephalitis caused by herpes simplex virus.

HSE auditing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herwaarden, A.J.F. van; Sykes, R.M.

1996-12-31

Shell International Exploration and Production (SIEP) commenced a programme of Health Safety and Environmental (HSE) auditing in its Operating Companies (Opcos) in the late 1970s. Audits in the initial years focused on safety aspects with environmental and occupational aspects being introduced as the process matured. Part of the audit programme is performed by SIEP auditors, external to the Opcos. The level of SIEP-led audit activity increased linearly until the late 1980s, since when a level of around 40 Audits per year has been maintained in roughly as many companies. For the last 15 years each annual programme has included structuredmore » audits of all facets of EP operations. The frequency and duration of these audits have the principle objective of auditing all HSE critical processes of each Opco`s activity, within each five-year cycle. Durations vary from 8-10 days with a 4 person team to 18-20 days with a 6-8 person team. Each audit returns a satisfactory or unsatisfactory rating based on analysis of the effectiveness of the so-called eleven principles of Enhanced Safety Management (ESM) required to be applied throughout the Group. Independence is maintained by the SIEP audit leader, who carries ultimate responsibility for the content and wording of each report, where necessary backed-up by senior management in SIEP. These SIEP-led audits have been successful in the following areas: (1) Provision of early warning in areas where facilities integrity or HSE management was likely to be compromised. (2) Aiding the establishment of an internal HSE auditing process in many Opcos. (3) Training, through participation in audits, not only auditors, but also prospective line managers in the effective management of HSE. With the recent introduction of HSE Management Systems (HSE-MS) in many Opcos, auditing is now in the process of controlled evolution from ESM to HSE-MS based.« less

An audit of smoking prevalence and awareness of HSE smoking cessation services among HSE staff.

PubMed

OhAiseadha, C; Killeen, M; Howell, F; Saunders, J

2014-04-01

This audit estimated smoking prevalence and awareness of quit services among Health Service Executive (HSE) staff. A questionnaire posted to a random sample of 1,064 staff received a 71% response rate. Staff smoking prevalence was 15.0% overall, and 4.4% among Medical/Dental staff. Front-line-healthcare staff were less likely to smoke than other staff categories (adjusted OR 0.38, p < 0.001). Only 63.6% of staff were aware of HSE quit services. Targeted interventions are required to help staff to quit smoking and to boost awareness of quit services.

Highly siderophile elements in Earth's mantle as a clock for the Moon-forming impact.

PubMed

Jacobson, Seth A; Morbidelli, Alessandro; Raymond, Sean N; O'Brien, David P; Walsh, Kevin J; Rubie, David C

2014-04-03

According to the generally accepted scenario, the last giant impact on Earth formed the Moon and initiated the final phase of core formation by melting Earth's mantle. A key goal of geochemistry is to date this event, but different ages have been proposed. Some argue for an early Moon-forming event, approximately 30 million years (Myr) after the condensation of the first solids in the Solar System, whereas others claim a date later than 50 Myr (and possibly as late as around 100 Myr) after condensation. Here we show that a Moon-forming event at 40 Myr after condensation, or earlier, is ruled out at a 99.9 per cent confidence level. We use a large number of N-body simulations to demonstrate a relationship between the time of the last giant impact on an Earth-like planet and the amount of mass subsequently added during the era known as Late Accretion. As the last giant impact is delayed, the late-accreted mass decreases in a predictable fashion. This relationship exists within both the classical scenario and the Grand Tack scenario of terrestrial planet formation, and holds across a wide range of disk conditions. The concentration of highly siderophile elements (HSEs) in Earth's mantle constrains the mass of chondritic material added to Earth during Late Accretion. Using HSE abundance measurements, we determine a Moon-formation age of 95 ± 32 Myr after condensation. The possibility exists that some late projectiles were differentiated and left an incomplete HSE record in Earth's mantle. Even in this case, various isotopic constraints strongly suggest that the late-accreted mass did not exceed 1 per cent of Earth's mass, and so the HSE clock still robustly limits the timing of the Moon-forming event to significantly later than 40 Myr after condensation.

Late accretion to the terrestrial planets

NASA Astrophysics Data System (ADS)

Brasser, Ramon; Mojzsis, Stephen; Werner, Stephanie; Matsumura, Soko; Ida, Shigeru

2017-10-01

IntroductionIt is generally accepted that silicate-metal (`rocky') planet formation relies on coagulation from a mixture of sub-Mars sized planetary embryos and (smaller) planetesimals that dynamically emerge from the evolving circum-solar disc in the first few million years of our Solar System. Once the planets have, for the most part, assembled after a giant impact phase, they continue to be bombarded by a multitude of planetesimals left over from accretion. Here we place limits on the mass and evolution of these planetesimals based on constraints from the highly siderophile element (HSE) budget of the Moon. The terrestrial and lunar HSE budgets indicate that Earth’s and Moon’s additions through late accretion were 0.7 wt% and 0.02 wt% respectively. The disproportionate high accretion between the Earth and Moon could be explained by stochastic accretion of a few remaining Ceres-sized bodies that preferentially targeted the Earth.ResultsFrom a combination of N-body and Monte Carlo simulations of planet formation we conclude:1) matching the terrestrial to lunar HSE ratio requires that late accretion on Earth mostly consisted of a single lunar-size impactor striking the Earth before 4.45 Ga2) the flux of terrestrial impactors must have been low avoid wholesale melting of Earth's crust after 4.4 Ga[6], and to simultaneously match the number of observed lunar basins3) after the terrestrial planets have fully formed, the mass in remnant planetesimals was ~0.001 Earth mass, lower than most previous models suggest.4) Mars' HSE budget also requires a colossal impact with a Ceres-sized object before 4.43 Ga, whose visible remnant could be the hemispherical dichotomy.These conclusions lead to an Hadean eon which is more clement than assumed previously. In addition, our dynamically and geochemically self-consistent scenario requires that future N-body simulations of rocky planet formation either directly incorporate collisional grinding or rely on pebble accretion.

Use of Clinical and Neuroimaging Characteristics to Distinguish Temporal Lobe Herpes Simplex Encephalitis From Its Mimics

PubMed Central

Chow, Felicia C.; Glaser, Carol A.; Sheriff, Heather; Xia, Dongxiang; Messenger, Sharon; Whitley, Richard; Venkatesan, Arun

2015-01-01

Background. We describe the spectrum of etiologies associated with temporal lobe (TL) encephalitis and identify clinical and radiologic features that distinguish herpes simplex encephalitis (HSE) from its mimics. Methods. We reviewed all adult cases of encephalitis with TL abnormalities on magnetic resonance imaging (MRI) from the California Encephalitis Project. We evaluated the association between specific clinical and MRI characteristics and HSE compared with other causes of TL encephalitis and used multivariate logistic modeling to identify radiologic predictors of HSE. Results. Of 251 cases of TL encephalitis, 43% had an infectious etiology compared with 16% with a noninfectious etiology. Of infectious etiologies, herpes simplex virus was the most commonly identified agent (n = 60), followed by tuberculosis (n = 8) and varicella zoster virus (n = 7). Of noninfectious etiologies, more than half (n = 21) were due to autoimmune disease. Patients with HSE were older (56.8 vs 50.2 years; P = .012), more likely to be white (53% vs 35%; P = .013), more likely to present acutely (88% vs 64%; P = .001) and with a fever (80% vs 49%; P < .001), and less likely to present with a rash (2% vs 15%; P = .010). In a multivariate model, bilateral TL involvement (odds ratio [OR], 0.38; 95% confidence interval [CI], .18–.79; P = .010) and lesions outside the TL, insula, or cingulate (OR, 0.37; 95% CI, .18–.74; P = .005) were associated with lower odds of HSE. Conclusions. In addition to HSE, other infectious and noninfectious etiologies should be considered in the differential diagnosis for TL encephalitis, depending on the presentation. Specific clinical and imaging features may aid in distinguishing HSE from non-HSE causes of TL encephalitis. PMID:25637586

T-cell Responses to HSV-1 in Persons Who Have Survived Childhood Herpes Simplex Encephalitis.

PubMed

Ott, Mariliis; Jing, Lichen; Lorenzo, Lazaro; Casanova, Jean-Laurent; Zhang, Shen-Ying; Koelle, David M

2017-08-01

Herpes simplex encephalitis (HSE) after primary herpes simplex virus (HSV)-1 infection can occur in children due to inborn errors of cell-intrinsic immunity in the central nervous system. Paradoxically, symptomatic mucocutaneous HSV-1 recurrences are rare survivors of childhood HSE. T-cell-acquired immunity is thought to be involved in control of recurrent mucocutaneous HSV infection. We thus tested HSV-1-specific immunity in HSE survivors. We obtained serum and peripheral blood mononuclear cells (PBMCs) from participants a median of 13.5 years after HSE. HSV-1 and HSV-2 IgG was detected by type-specific immunoblot. PBMCs from subjects passing quality control criteria were tested using enzyme-linked immunospot assay for CD4 interferon-γ responses with an HSV-1 lysate and for CD8 responses using pooled synthetic HSV-1 peptide CD8 T-cell epitopes. Healthy adult PBMCs were used to standardize assays and as comparators. All participants were HSV-1 seropositive. Most (23/24) HSE survivors had human leukocyte antigen class I types matching the human leukocyte antigen restriction of the pooled peptides. We detected HSV-specific CD8 T-cell responses in 14 of 24 (58%) HSE survivors and in 9 of 9 healthy HSV-1 seropositive adults. HSV-specific CD4 T-cell responses were present in all 5 HSE subjects tested and in 8 of 9 healthy adults. Response magnitudes were overlapping between subject groups. The defects in cell-intrinsic immunity leading to failure to control primary central nervous system HSV-1 infection do not preclude the acquisition of specific immunity or the control of recurrent mucocutaneous HSV infections. The rarity and lack of severe or recurrent mucocutaneous HSV infection in survivors of childhood HSE corresponds with intact adaptive T-cell immunity.

Hwanggeumchal sorghum Induces Cell Cycle Arrest, and Suppresses Tumor Growth and Metastasis through Jak2/STAT Pathways in Breast Cancer Xenografts

PubMed Central

Lim, Eun Joung; Joung, Youn Hee; Hong, Dae Young; Park, Eui U.; Park, Seung Hwa; Choi, Soo Keun; Moon, Eon-Soo; Cho, Byung Wook; Park, Kyung Do; Lee, Hak Kyo; Kim, Myong-Jo; Park, Dong-Sik; Yang, Young Mok

2012-01-01

Background Cancer is one of the highly virulent diseases known to humankind with a high mortality rate. Breast cancer is the most common cancer in women worldwide. Sorghum is a principal cereal food in many parts of the world, and is critical in folk medicine of Asia and Africa. In the present study, we analyzed the effects of HSE in metastatic breast cancer. Methodology/Principal Findings Preliminary studies conducted on MDA-MB 231 and MCF-7 xenograft models showed tumor growth suppression by HSE. Western blotting studies conducted both in vivo and in vitro to check the effect of HSE in Jak/STAT pathways. Anti-metastatic effects of HSE were confirmed using both MDA-MB 231 and MCF-7 metastatic animal models. These studies showed that HSE can modulate Jak/STAT pathways, and it hindered the STAT5b/IGF-1R and STAT3/VEGF pathways not only by down-regulating the expression of these signal molecules and but also by preventing their phosphorylation. The expression of angiogenic factors like VEGF, VEGF-R2 and cell cycle regulators like cyclin D, cyclin E, and pRb were found down-regulated by HSE. In addition, it also targets Brk, p53, and HIF-1α for anti-cancer effects. HSE induced G1 phase arrest and migration inhibition in MDA-MB 231 cells. The metastasis of breast cancer to the lungs also found blocked by HSE in the metastatic animal model. Conclusions/Significance Usage of HS as a dietary supplement is an inexpensive natural cancer therapy, without any side effects. We strongly recommend the use of HS as an edible therapeutic agent as it possesses tumor suppression, migration inhibition, and anti-metastatic effects on breast cancer. PMID:22792362

Health systems engineering fellowship: curriculum and program development.

PubMed

Watts, Bradley V; Shiner, Brian; Cully, Jeffrey A; Gilman, Stuart C; Benneyan, James C; Eisenhauer, William

2015-01-01

Industrial engineering and related disciplines have been used widely in improvement efforts in many industries. These approaches have been less commonly attempted in health care. One factor limiting application is the limited workforce resulting from a lack of specific education and professional development in health systems engineering (HSE). The authors describe the development of an HSE fellowship within the United States Department of Veterans Affairs, Veterans Health Administration (VA). This fellowship includes a novel curriculum based on specifically established competencies for HSE. A 1-year HSE curriculum was developed and delivered to fellows at several VA engineering resource centers over several years. On graduation, a majority of the fellows accepted positions in the health care field. Challenges faced in developing the fellowship are discussed. Advanced educational opportunities in applied HSE have the potential to develop the workforce capacity needed to improve the quality of health care. © 2014 by the American College of Medical Quality.

HSE training and competence assessment in the geophysical industry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Covil, M.W.; Soethout, J.A.; Reynolds, G.

1996-11-01

This paper looks at the efforts of the seismic geophysical industry to continually improve it`s health, safety and environmental performance, and in particular to improve the HSE behavior and understanding of individuals within the industry. Specifically it deals with the HSE training and assessment of competence of individuals in relation to their job responsibilities, based on best industry practice.

Herpes Simplex Encephalitis Complicated by Cerebral Hemorrhage during Acyclovir Therapy.

PubMed

Harada, Yukinori; Hara, Yuuta

2017-01-01

Herpes simplex encephalitis (HSE) can be complicated by adverse events in the acute phase. We herein present the case of a 71-year-old woman with HSE complicated by cerebral hemorrhage. She presented with acute deterioration of consciousness and fever and was diagnosed with HSE based on the detection of herpes simplex virus-1 in the cerebrospinal fluid by a polymerase chain reaction. The cerebral hemorrhage developed during acyclovir therapy; however, its diagnosis was delayed for 2 days. After the conservative treatment of the cerebral hemorrhage, the patient made a near-complete recovery. Cerebral hemorrhage should be considered as an acute-phase complication of HSE.

CdS quantum dots as fluorescence probes for the sensitive and selective detection of highly reactive HSe- ions in aqueous solution.

PubMed

Wu, Chuan-Liu; Zhao, Yi-Bing

2007-06-01

Water-soluble cadmium sulfide (CdS) quantum dots (QDs) capped by mercaptoacetic acid were synthesized by aqueous-phase arrested precipitation, and characterized by transmission electron microscopy, spectrofluorometry, and UV-Vis spectrophotometry. The prepared luminescent water-soluble CdS QDs were evaluated as fluorescence probes for the detection of highly reactive hydrogen selenide ions (HSe(-) ions). The quenching of the fluorescence emission of CdS QDs with the addition of HSe(-) ions is due to the elimination of the S(2-) vacancies which are luminescence centers. Quantitative analysis based on chemical interaction between HSe(-) ions and the surface of CdS QDs is very simple, easy to develop, and has demonstrated very high sensitivity and selectivity features. The effect of foreign ions (common anions and biologically relevant cations) on the fluorescence of the CdS QDs was examined to evaluate the selectivity. Only Cu(2+) and S(2-) ions exhibit significant effects on the fluorescence of CdS QDs. With the developed method, we are able to determine the concentration of HSe(-) ions in the range from 0.10 to 4.80 micromol L(-1), and the limit of detection is 0.087 micromol L(-1). The proposed method was successfully applied to monitor the obtained HSe(-) ions from the reaction of glutathione with selenite. To the best of our knowledge, this is the first report on fluorescence analysis of HSe(-) ions in aqueous solution.

Critical role of microRNA-155 in herpes simplex encephalitis.

PubMed

Bhela, Siddheshvar; Mulik, Sachin; Reddy, Pradeep B J; Richardson, Raphael L; Gimenez, Fernanda; Rajasagi, Naveen K; Veiga-Parga, Tamara; Osmand, Alexander P; Rouse, Barry T

2014-03-15

HSV infection of adult humans occasionally results in life-threatening herpes simplex encephalitis (HSE) for reasons that remain to be defined. An animal system that could prove useful to model HSE could be microRNA-155 knockout (miR-155KO) mice. Thus, we observe that mice with a deficiency of miR-155 are highly susceptible to HSE with a majority of animals (75-80%) experiencing development of HSE after ocular infection with HSV-1. The lesions appeared to primarily represent the destructive consequences of viral replication, and animals could be protected from HSE by acyclovir treatment provided 4 d after ocular infection. The miR-155KO animals were also more susceptible to development of zosteriform lesions, a reflection of viral replication and dissemination within the nervous system. One explanation for the heightened susceptibility to HSE and zosteriform lesions could be because miR-155KO animals develop diminished CD8 T cell responses when the numbers, functionality, and homing capacity of effector CD8 T cell responses were compared. Indeed, adoptive transfer of HSV-immune CD8 T cells to infected miR-155KO mice at 24 h postinfection provided protection from HSE. Deficiencies in CD8 T cell numbers and function also explained the observation that miR-155KO animals were less able than control animals to maintain HSV latency. To our knowledge, our observations may be the first to link miR-155 expression with increased susceptibility of the nervous system to virus infection.

Asking about Sex in General Health Surveys: Comparing the Methods and Findings of the 2010 Health Survey for England with Those of the Third National Survey of Sexual Attitudes and Lifestyles

PubMed Central

Prah, Philip; Johnson, Anne M.; Nardone, Anthony; Clifton, Soazig; Mindell, Jennifer S.; Copas, Andrew J.; Robinson, Chloe; Craig, Rachel; Woodhall, Sarah C.; Macdowall, Wendy; Fuller, Elizabeth; Erens, Bob; Sonnenberg, Pam; Wellings, Kaye; Mercer, Catherine H.

2015-01-01

Objectives Including questions about sexual health in the annual Health Survey for England (HSE) provides opportunities for regular measurement of key public health indicators, augmenting Britain's decennial National Survey of Sexual Attitudes and Lifestyles (Natsal). However, contextual and methodological differences may limit comparability of the findings. We examine the extent of these differences between HSE 2010 and Natsal-3 and investigate their impact on parameter estimates. Methods Complex survey analyses of data from men and women in the 2010 HSE (n = 2,782 men and 3,588 women) and Natsal-3 undertaken 2010–2012 (n = 4,882 men and 6,869 women) aged 16-69y and resident in England, both using probability sampling, compared their characteristics, the amount of non-response to, and estimates from, sexual health questions. Both surveys used self-completion for the sexual behaviour questions but this was via computer-assisted self-interview (CASI) in Natsal-3 and a pen-and-paper questionnaire in HSE 2010. Results The surveys achieved similar response rates, both around 60%, and demographic profiles largely consistent with the census, although HSE participants tended to be less educated, and reported worse general health, than Natsal-3 participants. Item non-response to the sexual health questions was typically higher in HSE 2010 (range: 9–18%) relative to Natsal-3 (all <5%). Prevalence estimates for sexual risk behaviours and STI-related indicators were generally slightly lower in HSE 2010 than Natsal-3. Conclusions While a relatively high response to sexual health questions in HSE 2010 demonstrates the feasibility of asking such questions in a general health survey, differences with Natsal-3 do exist. These are likely due to the HSE’s context as a general health survey and methodological limitations such as its current use of pen-and-paper questionnaires. Methodological developments to the HSE should be considered so that its data can be interpreted in combination with those from dedicated sexual health surveys, thus improving our ability to monitor trends in sexual health. PMID:26252650

Development of a Full-Thickness Human Skin Equivalent In Vitro Model Derived from TERT-Immortalized Keratinocytes and Fibroblasts

PubMed Central

Reijnders, Christianne M.A.; van Lier, Amanda; Roffel, Sanne; Kramer, Duco; Scheper, Rik J.

2015-01-01

Currently, human skin equivalents (HSEs) used for in vitro assays (e.g., for wound healing) make use of primary human skin cells. Limitations of primary keratinocytes and fibroblasts include availability of donor skin and donor variation. The use of physiologically relevant cell lines could solve these limitations. The aim was to develop a fully differentiated HSE constructed entirely from human skin cell lines, which could be applied for in vitro wound-healing assays. Skin equivalents were constructed from human TERT-immortalized keratinocytes and fibroblasts (TERT-HSE) and compared with native skin and primary HSEs. HSEs were characterized by hematoxylin–eosin and immunohistochemical stainings with markers for epidermal proliferation and differentiation, basement membrane (BM), fibroblasts, and the extracellular matrix (ECM). Ultrastructure was determined with electron microscopy. To test the functionality of the TERT-HSE, burn and cold injuries were applied, followed by immunohistochemical stainings, measurement of reepithelialization, and determination of secreted wound-healing mediators. The TERT-HSE was composed of a fully differentiated epidermis and a fibroblast-populated dermis comparable to native skin and primary HSE. The epidermis consisted of proliferating keratinocytes within the basal layer, followed by multiple spinous layers, a granular layer, and cornified layers. Within the TERT-HSE, the membrane junctions such as corneosomes, desmosomes, and hemidesmosomes were well developed as shown by ultrastructure pictures. Furthermore, the BM consisted of a lamina lucida and lamina densa comparable to native skin. The dermal matrix of the TERT-HSE was more similar to native skin than the primary construct, since collagen III, an ECM marker, was present in TERT-HSEs and absent in primary HSEs. After wounding, the TERT-HSE was able to reepithelialize and secrete inflammatory wound-healing mediators. In conclusion, the novel TERT-HSE, constructed entirely from human cell lines, provides an excellent opportunity to study in vitro skin biology and can also be used for drug targeting and testing new therapeutics, and ultimately, for incorporating into skin-on-a chip in the future. PMID:26135533

High storm surge events in Venice and the 11-yr solar cycle

NASA Astrophysics Data System (ADS)

Barriopedro, David; García-Herrera, Ricardo; Lionello, Piero; Pino, Cosimo

2010-05-01

In the last years the Venice lagoon has received much attention as a case of coastal vulnerability, mainly because of relative sea level rise and increase frequency of storm surge events, the so-called "aqua alta", which, particularly during autumn, cause the flooding of the Venice historical city center. Long-term fluctuations in solar activity and large-scale climate patterns have been suggested as feasible factors of flooding variability. This study explores the long-term frequency variability of High Surge Events (HSE) in Venice for the period 1948-2008 and its modulation by the 11-yr solar cycle. A significant decadal variability in the frequency of HSE is found in good correspondence with the 11-yr cycle, solar maxima being associated to a significant increase of the October-November-December HSE frequency. A Storm Surge Pattern (SSP), i.e. the seasonal 1000 hPa height pattern associated to increased frequency of HSE, is identified and found similar to the positive phase of the main variability mode of the regional atmospheric circulation (EOF1). However, further analyses indicate that the increase of HSE in solar maxima cannot be simply explained by a higher recurrence of positive EOF1 phases during high solar years. It rather seems that solar activity modulates the spatial patterns of the atmospheric circulation (EOF) and the favorable conditions for HSE occurrence (SSP). Thus, under solar maxima, the occurrence of HSE is enhanced by the EOF1, namely a large-scale wave train pattern that is symptomatic of storm track paths over northern Europe. Solar minima reveal a substantially different and less robust SSP, consisting of a meridionally oriented dipole with a preferred southward path of storm track activity, which is not associated to any EOF during low solar periods. It is concluded that solar activity plays an indirect role in the frequency of HSE by modulating the spatial patterns of the main modes of atmospheric regional variability, the favorable patterns for HSE occurrence and their mutual relationships, so that constructive interaction between them is enhanced during solar maxima and inhibited in solar minima.

Validity of the coding for herpes simplex encephalitis in the Danish National Patient Registry

PubMed Central

Jørgensen, Laura Krogh; Dalgaard, Lars Skov; Østergaard, Lars Jørgen; Andersen, Nanna Skaarup; Nørgaard, Mette; Mogensen, Trine Hyrup

2016-01-01

Background Large health care databases are a valuable source of infectious disease epidemiology if diagnoses are valid. The aim of this study was to investigate the accuracy of the recorded diagnosis coding of herpes simplex encephalitis (HSE) in the Danish National Patient Registry (DNPR). Methods The DNPR was used to identify all hospitalized patients, aged ≥15 years, with a first-time diagnosis of HSE according to the International Classification of Diseases, tenth revision (ICD-10), from 2004 to 2014. To validate the coding of HSE, we collected data from the Danish Microbiology Database, from departments of clinical microbiology, and from patient medical records. Cases were classified as confirmed, probable, or no evidence of HSE. We estimated the positive predictive value (PPV) of the HSE diagnosis coding stratified by diagnosis type, study period, and department type. Furthermore, we estimated the proportion of HSE cases coded with nonspecific ICD-10 codes of viral encephalitis and also the sensitivity of the HSE diagnosis coding. Results We were able to validate 398 (94.3%) of the 422 HSE diagnoses identified via the DNPR. Hereof, 202 (50.8%) were classified as confirmed cases and 29 (7.3%) as probable cases providing an overall PPV of 58.0% (95% confidence interval [CI]: 53.0–62.9). For “Encephalitis due to herpes simplex virus” (ICD-10 code B00.4), the PPV was 56.6% (95% CI: 51.1–62.0). Similarly, the PPV for “Meningoencephalitis due to herpes simplex virus” (ICD-10 code B00.4A) was 56.8% (95% CI: 39.5–72.9). “Herpes viral encephalitis” (ICD-10 code G05.1E) had a PPV of 75.9% (95% CI: 56.5–89.7), thereby representing the highest PPV. The estimated sensitivity was 95.5%. Conclusion The PPVs of the ICD-10 diagnosis coding for adult HSE in the DNPR were relatively low. Hence, the DNPR should be used with caution when studying patients with encephalitis caused by herpes simplex virus. PMID:27330328

"First-person view" of pathogen transmission and hand hygiene - use of a new head-mounted video capture and coding tool.

PubMed

Clack, Lauren; Scotoni, Manuela; Wolfensberger, Aline; Sax, Hugo

2017-01-01

Healthcare workers' hands are the foremost means of pathogen transmission in healthcare, but detailed hand trajectories have been insufficiently researched so far. We developed and applied a new method to systematically document hand-to-surface exposures (HSE) to delineate true hand transmission pathways in real-life healthcare settings. A head-mounted camera and commercial coding software were used to capture ten active care episodes by eight nurses and two physicians and code HSE type and duration using a hierarchical coding scheme. We identified HSE sequences of particular relevance to infectious risks for patients based on the WHO 'Five Moments for Hand Hygiene'. The study took place in a trauma intensive care unit in a 900-bed university hospital in Switzerland. Overall, the ten videos totaled 296.5 min and featured eight nurses and two physicians. A total of 4222 HSE were identified (1 HSE every 4.2 s), which concerned bare (79%) and gloved (21%) hands. The HSE inside the patient zone ( n  = 1775; 42%) included mobile objects (33%), immobile surfaces (5%), and patient intact skin (4%), while HSE outside the patient zone ( n  = 1953; 46%) included HCW's own body (10%), mobile objects (28%), and immobile surfaces (8%). A further 494 (12%) events involved patient critical sites. Sequential analysis revealed 291 HSE transitions from outside to inside patient zone, i.e. "colonization events", and 217 from any surface to critical sites, i.e. "infection events". Hand hygiene occurred 97 times, 14 (5% adherence) times at colonization events and three (1% adherence) times at infection events. On average, hand rubbing lasted 13 ± 9 s. The abundance of HSE underscores the central role of hands in the spread of potential pathogens while hand hygiene occurred rarely at potential colonization and infection events. Our approach produced a valid video and coding instrument for in-depth analysis of hand trajectories during active patient care that may help to design more efficient prevention schemes.

Development of a Full-Thickness Human Skin Equivalent In Vitro Model Derived from TERT-Immortalized Keratinocytes and Fibroblasts.

PubMed

Reijnders, Christianne M A; van Lier, Amanda; Roffel, Sanne; Kramer, Duco; Scheper, Rik J; Gibbs, Susan

2015-09-01

Currently, human skin equivalents (HSEs) used for in vitro assays (e.g., for wound healing) make use of primary human skin cells. Limitations of primary keratinocytes and fibroblasts include availability of donor skin and donor variation. The use of physiologically relevant cell lines could solve these limitations. The aim was to develop a fully differentiated HSE constructed entirely from human skin cell lines, which could be applied for in vitro wound-healing assays. Skin equivalents were constructed from human TERT-immortalized keratinocytes and fibroblasts (TERT-HSE) and compared with native skin and primary HSEs. HSEs were characterized by hematoxylin-eosin and immunohistochemical stainings with markers for epidermal proliferation and differentiation, basement membrane (BM), fibroblasts, and the extracellular matrix (ECM). Ultrastructure was determined with electron microscopy. To test the functionality of the TERT-HSE, burn and cold injuries were applied, followed by immunohistochemical stainings, measurement of reepithelialization, and determination of secreted wound-healing mediators. The TERT-HSE was composed of a fully differentiated epidermis and a fibroblast-populated dermis comparable to native skin and primary HSE. The epidermis consisted of proliferating keratinocytes within the basal layer, followed by multiple spinous layers, a granular layer, and cornified layers. Within the TERT-HSE, the membrane junctions such as corneosomes, desmosomes, and hemidesmosomes were well developed as shown by ultrastructure pictures. Furthermore, the BM consisted of a lamina lucida and lamina densa comparable to native skin. The dermal matrix of the TERT-HSE was more similar to native skin than the primary construct, since collagen III, an ECM marker, was present in TERT-HSEs and absent in primary HSEs. After wounding, the TERT-HSE was able to reepithelialize and secrete inflammatory wound-healing mediators. In conclusion, the novel TERT-HSE, constructed entirely from human cell lines, provides an excellent opportunity to study in vitro skin biology and can also be used for drug targeting and testing new therapeutics, and ultimately, for incorporating into skin-on-a chip in the future.

On the nature of the Ni-rich component in splash-form Australasian tektites

NASA Astrophysics Data System (ADS)

Goderis, Steven; Tagle, Roald; Fritz, Jörg; Bartoschewitz, Rainer; Artemieva, Natalia

2017-11-01

The Australasian tektite strewn field is exceptional, not only as the largest and most recent, but also as the only strewn field without an identified source impact crater. Therefore, scenarios without the formation of an impact crater, such as a low altitude cometary airburst, have proven hard to discard. Here, new geochemical evidence is presented for mixing of projectile and target material, which implies the formation of an Australasian tektite-related impact crater. First, ninety-two Australasian tektites were grouped according to their Cr, Co and Ni concentrations. Based on this data, Australasian tektites with the highest Ni contents (>200 μg/g) occur more than 1500 km south-southeast (SSE) of the northern Indochina region, with the highest concentration of Ni-rich tektites in South Vietnam, the islands of Borneo, Belitung, and Java, and reports in literature for Ni-rich tektites in central Australia. The tektites with the highest Cr and Ni abundances often also show highly siderophile element (HSE) enrichments of up to 4 ng/g Ir. The most Ni-rich samples exhibit broadly chondrite-relative HSE proportions. However, a chondritic impactor contribution appears to be inconsistent with the observed Ni/Cr, Ni/Co, and Cr/Co ratios. A previously suggested significant terrestrial mantle contribution can also not explain the siderophile element enrichments in combination with relatively low FeOtot (<7 wt.%) and MgO (<4 wt.%) contents. Elemental fractionation during impact cratering or tektite formation by an impactor with a chondritic signature may explain these observations. Alternatively, a projectile component from a primitive achondrite may be advocated, with contribution from a mafic to ultramafic extraterrestrial lithology with a relatively unfractionated HSE signature and Ni/Cr ratio distinctly higher than those of Earth's mantle. Element distribution maps obtained from individual Australasian tektites document complex mingling processes of chemically distinct melt batches, each exhibiting variable contributions from distinct endmember compositions. These texturally recorded mingling processes are consistent with high-resolution numerical models of impact cratering processes that resolve the growth of Kelvin-Helmholtz instabilities at the projectile/target interface during impact, when both materials co-occur at high pressure. These numerical models indicate that Ni-rich tektite populations across the central part of the Australasian tektite strewn field could represent projectile-enriched material preferentially ejected downrange. Continued tracing of this Ni-rich component across the strewn field may help to constrain the location of the yet to be identified source crater of the Australasian (micro)tektites.

Effects of decompressive surgery on prognosis and cognitive deficits in herpes simplex encephalitis.

PubMed

Midi, Ipek; Tuncer, Nese; Midi, Ahmet; Mollahasanoglu, Aynur; Konya, Deniz; Sav, Aydin

2007-01-01

Herpes simplex encephalitis (HSE) is a serious viral infection with a high rate of mortality. The most commonly seen complications are behavioral changes, seizures and memory deficits. We report the case of a 37-year-old man with HSE in the right temporal lobe and a severe midline shift who was treated with acyclovir. The patient underwent anterior temporal lobe resection. Although HSE can cause permanent cognitive deficits, in this case, early surgical intervention minimized any deficit, as determined by detailed neuropsychological examination. Surgical decompression is indicated as early as possible in severe cases. This case report emphasizes the effect of surgical decompression for HSE on cognitive function, which has rarely been mentioned before.

Siderophile Element Constraints on the Origin of the Moon

NASA Astrophysics Data System (ADS)

Walker, R. J.; Day, J. M.

2016-12-01

Siderophile elements provide important clues to the origin of the Moon. One key feature of the Earth-Moon system is the estimated 20X lower abundances of highly siderophile elements (HSE) in the accessible lunar mantle, compared to the bulk silicate Earth. This has been attributed to the disproportional addition of materials with chondritic bulk compositions to the mantles of each body by stochastic late accretion. When corrected for late accretionary differences, the two bodies appear to have 182W compositions that are identical to within a few ppm. This observation follows other evidence for isotopic similarity between the two bodies (e.g., O, Ti and Cr) which record the genetic signatures of planetary building blocks. Giant impact models have been sought to account for the isotopic similarities between the Moon and Earth, given the outcomes of some scenarios that the Moon is composed mainly of impactor materials. This may indicate the proto-Earth and giant impactor formed from genetically similar materials. The similarity in 182W is more problematic because the 182Hf-182W system is radiogenic (t½ = 8.9 Ma), and the proportion of 182W present in each body reflects the average timing of core formation, combined with the Hf/W. The collision of two planetary bodies with essentially identical 182W is improbable, so the isotopic match provides strong evidence of isotopic mixing between the Earth's mantle and proto-lunar disk. The identical 182W for the Earth and Moon at the time of formation also argues for formation of the Moon >60 Ma after solar system formation, as previously suggested, although this constraint is relaxed if the Hf/W of the mantles of both bodies are the same to within a few percent. The homogeneity of 182W in disparate products of the lunar magma ocean also argues for system closure occurring >60 Ma after solar system formation. If the interpretation of disproportional late accretion is correct, then the late accretionary accumulation clocks for both the Moon and Earth began at the time of the giant impact, which must have been a clearinghouse event for any HSE that were present in the terrestrial mantle prior to the impact. This means that at least some of the metal from the core of the impactor efficiently extracted HSE from the silicate Earth while en route to merge with Earth's core.

An integrated experiment for identification of best decision styles and teamworks with respect to HSE and ergonomics program: The case of a large oil refinery.

PubMed

Azadeh, A; Mokhtari, Z; Sharahi, Z Jiryaei; Zarrin, M

2015-12-01

Decision making failure is a predominant human error in emergency situations. To demonstrate the subject model, operators of an oil refinery were asked to answer a health, safety and environment HSE-decision styles (DS) questionnaire. In order to achieve this purpose, qualitative indicators in HSE and ergonomics domain have been collected. Decision styles, related to the questions, have been selected based on Driver taxonomy of human decision making approach. Teamwork efficiency has been assessed based on different decision style combinations. The efficiency has been ranked based on HSE performance. Results revealed that efficient decision styles resulted from data envelopment analysis (DEA) optimization model is consistent with the plant's dominant styles. Therefore, improvement in system performance could be achieved using the best operator for critical posts or in team arrangements. This is the first study that identifies the best decision styles with respect to HSE and ergonomics factors. Copyright © 2015 Elsevier Ltd. All rights reserved.

New Prediction Model for Probe Specificity in an Allele-Specific Extension Reaction for Haplotype-Specific Extraction (HSE) of Y Chromosome Mixtures

PubMed Central

Rothe, Jessica; Watkins, Norman E.; Nagy, Marion

2012-01-01

Allele-specific extension reactions (ASERs) use 3′ terminus-specific primers for the selective extension of completely annealed matches by polymerase. The ability of the polymerase to extend non-specific 3′ terminal mismatches leads to a failure of the reaction, a process that is only partly understood and predictable, and often requires time-consuming assay design. In our studies we investigated haplotype-specific extraction (HSE) for the separation of male DNA mixtures. HSE is an ASER and provides the ability to distinguish between diploid chromosomes from one or more individuals. Here, we show that the success of HSE and allele-specific extension depend strongly on the concentration difference between complete match and 3′ terminal mismatch. Using the oligonucleotide-modeling platform Visual Omp, we demonstrated the dependency of the discrimination power of the polymerase on match- and mismatch-target hybridization between different probe lengths. Therefore, the probe specificity in HSE could be predicted by performing a relative comparison of different probe designs with their simulated differences between the duplex concentration of target-probe match and mismatches. We tested this new model for probe design in more than 300 HSE reactions with 137 different probes and obtained an accordance of 88%. PMID:23049901

Mutations in the TLR3 signaling pathway and beyond in adult patients with herpes simplex encephalitis.

PubMed

Mørk, N; Kofod-Olsen, E; Sørensen, K B; Bach, E; Ørntoft, T F; Østergaard, L; Paludan, S R; Christiansen, M; Mogensen, T H

2015-12-01

Herpes simplex encephalitis (HSE) in children has previously been linked to defects in type I interferon production downstream of Toll-like receptor (TLR)3. In the present study, we used whole-exome sequencing to investigate the genetic profile of 16 adult patients with a history of HSE. We identified novel mutations in IRF3, TYK2 and MAVS, molecules involved in generating innate antiviral immune responses, which have not previously been associated with HSE. Moreover, data revealed mutations in TLR3, TRIF, TBK1 and STAT1 known to be associated with HSE in children but not previously described in adults. All discovered mutations were heterozygous missense mutations, the majority of which were associated with significantly decreased antiviral responses to HSV-1 infection and/or the TLR3 agonist poly(I:C) in patient peripheral blood mononuclear cells compared with controls. Altogether, this study demonstrates novel mutations in the TLR3 signaling pathway in molecules previously identified in children, suggesting that impaired innate immunity to HSV-1 may also increase susceptibility to HSE in adults. Importantly, the identification of mutations in innate signaling molecules not directly involved in TLR3 signaling suggests the existence of innate immunodeficiencies predisposing to HSE beyond the TLR3 pathway.

Herpes simplex encephalitis : from virus to therapy.

PubMed

Rozenberg, Flore; Deback, Claire; Agut, Henri

2011-06-01

Herpes simplex virus (HSV) is the cause of herpes simplex encephalitis (HSE), a devastating human disease which occurs in 2-4 cases per million/year. HSE results either from a primary infection or virus reactivation, in accordance with the common pattern of HSV infection which is a chronic lifelong process. However its pathophysiology remains largely unknown and its poor prognosis is in contrast with the usually good tolerance of most clinical herpetic manifestations. HSE is due to HSV type 1 (HSV-1) in most cases but HSV type 2 (HSV-2) may be also implicated, especially in infants in the context of neonatal herpes. Polymerase chain reaction detection of HSV DNA in cerebrospinal fluid is the diagnosis of choice for HSE. Acyclovir, a nucleoside analogue which inhibits viral DNA polymerase activity, is the reference treatment of HSE while foscarnet constitutes an alternative therapy and the efficacy of cidofovir is currently uncertain in that context. The emergence of HSV resistance to acyclovir, a phenomenon which is mainly observed among immunocompromised patients, is a current concern although no case of HSE due to an acyclovir-resistant HSV strain has been reported to date. Nevertheless the identification and development of novel therapeutic strategies against HSV appears to be a non dispensable objective for future research in virology.

New prediction model for probe specificity in an allele-specific extension reaction for haplotype-specific extraction (HSE) of Y chromosome mixtures.

PubMed

Rothe, Jessica; Watkins, Norman E; Nagy, Marion

2012-01-01

Allele-specific extension reactions (ASERs) use 3' terminus-specific primers for the selective extension of completely annealed matches by polymerase. The ability of the polymerase to extend non-specific 3' terminal mismatches leads to a failure of the reaction, a process that is only partly understood and predictable, and often requires time-consuming assay design. In our studies we investigated haplotype-specific extraction (HSE) for the separation of male DNA mixtures. HSE is an ASER and provides the ability to distinguish between diploid chromosomes from one or more individuals. Here, we show that the success of HSE and allele-specific extension depend strongly on the concentration difference between complete match and 3' terminal mismatch. Using the oligonucleotide-modeling platform Visual Omp, we demonstrated the dependency of the discrimination power of the polymerase on match- and mismatch-target hybridization between different probe lengths. Therefore, the probe specificity in HSE could be predicted by performing a relative comparison of different probe designs with their simulated differences between the duplex concentration of target-probe match and mismatches. We tested this new model for probe design in more than 300 HSE reactions with 137 different probes and obtained an accordance of 88%.

Herpes Simplex Encephalitis (HSE) and its outcome in the Patients who were Admitted to a Tertiary Care Hospital in Mashhad, Iran, over a 10-year Period.

PubMed

Sheybani, F; Arabikhan, H R; Naderi, H R

2013-08-01

The effective cure rate of acyclovir emphasizes the importance of an early diagnosis and treatment in reducing the considerable mortality and the morbidity in patients with Herpes Simplex Encephalitis (HSE). The demographic as well as clinical features, the lab data and the neuroimaging findings of the patients with HSE, which were confirmed by Cerebrospinal Fluid (CSF) PCR and/or brain MRI, were reviewed and analyzed statistically over a 10-year period. Over a 10-year period, the characteristics of 45 patients with HSE were reviewed. 34 (76%) out of the 45 patients showed positive CSF HSV-1 PCR results. 8 (18%) had a normal CSF analysis and a CSF/blood glucose ratio of less than 0.5 was observed in 13 (29%) patients, while 14% had PMN-dominant pleocytosis. 68% of the patients for whom brain MRI was performed, had temporal lobe involvement. While 37 (83%) patients recovered completely, 6 (13%) survived with sequelae, and 2 (4%) died. Because of the increasing number of atypical forms of HSE and the great impact of an early diagnosis and treatment on a favourable outcome, the acyclovir therapy should be administrated for any type of febrile encephalopathy of unknown aetiology, until HSE can be excluded.

Prevalence of Intrathecal Acyclovir Resistant Virus in Herpes Simplex Encephalitis Patients.

PubMed

Mitterreiter, Johanna G; Titulaer, Maarten J; van Nierop, Gijsbert P; van Kampen, Jeroen J A; Aron, Georgina I; Osterhaus, Albert D M E; Verjans, Georges M G M; Ouwendijk, Werner J D

2016-01-01

Herpes simplex encephalitis (HSE) is a life-threatening complication of herpes simplex virus (HSV) infection. Acyclovir (ACV) is the antiviral treatment of choice, but may lead to emergence of ACV-resistant (ACVR) HSV due to mutations in the viral UL23 gene encoding for the ACV-targeted thymidine kinase (TK) protein. Here, we determined the prevalence of intrathecal ACVR-associated HSV TK mutations in HSE patients and compared TK genotypes of sequential HSV isolates in paired cerebrospinal fluid (CSF) and blister fluid of mucosal HSV lesions. Clinical samples were obtained from 12 HSE patients, encompassing 4 HSV type 1 (HSV-1) and 8 HSV-2 encephalitis patients. HSV DNA load was determined by real-time PCR and complete HSV TK gene sequences were obtained by nested PCR followed by Sanger sequencing. All HSV-1 HSE patients contained viral TK mutations encompassing 30 unique nucleotide and 13 distinct amino acid mutations. By contrast, a total of 5 unique nucleotide and 4 distinct amino acid changes were detected in 7 of 8 HSV-2 patients. Detected mutations were identified as natural polymorphisms located in non-conserved HSV TK gene regions. ACV therapy did not induce the emergence of ACVR-associated HSV TK mutations in consecutive CSF and mucocutaneous samples of 5 individual patients. Phenotypic susceptibility analysis of these mucocutaneous HSV isolates demonstrated ACV-sensitive virus in 2 HSV-1 HSE patients, whereas in two HSV-2 HSE patients ACVR virus was detected in the absence of known ACVR-associated TK mutations. In conclusion, we did not detect intrathecal ACVR-associated TK mutations in HSV isolates obtained from 12 HSE patients.

Use of clinical and neuroimaging characteristics to distinguish temporal lobe herpes simplex encephalitis from its mimics.

PubMed

Chow, Felicia C; Glaser, Carol A; Sheriff, Heather; Xia, Dongxiang; Messenger, Sharon; Whitley, Richard; Venkatesan, Arun

2015-05-01

We describe the spectrum of etiologies associated with temporal lobe (TL) encephalitis and identify clinical and radiologic features that distinguish herpes simplex encephalitis (HSE) from its mimics. We reviewed all adult cases of encephalitis with TL abnormalities on magnetic resonance imaging (MRI) from the California Encephalitis Project. We evaluated the association between specific clinical and MRI characteristics and HSE compared with other causes of TL encephalitis and used multivariate logistic modeling to identify radiologic predictors of HSE. Of 251 cases of TL encephalitis, 43% had an infectious etiology compared with 16% with a noninfectious etiology. Of infectious etiologies, herpes simplex virus was the most commonly identified agent (n = 60), followed by tuberculosis (n = 8) and varicella zoster virus (n = 7). Of noninfectious etiologies, more than half (n = 21) were due to autoimmune disease. Patients with HSE were older (56.8 vs 50.2 years; P = .012), more likely to be white (53% vs 35%; P = .013), more likely to present acutely (88% vs 64%; P = .001) and with a fever (80% vs 49%; P < .001), and less likely to present with a rash (2% vs 15%; P = .010). In a multivariate model, bilateral TL involvement (odds ratio [OR], 0.38; 95% confidence interval [CI], .18-.79; P = .010) and lesions outside the TL, insula, or cingulate (OR, 0.37; 95% CI, .18-.74; P = .005) were associated with lower odds of HSE. In addition to HSE, other infectious and noninfectious etiologies should be considered in the differential diagnosis for TL encephalitis, depending on the presentation. Specific clinical and imaging features may aid in distinguishing HSE from non-HSE causes of TL encephalitis. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

[Clinical characteristics, prognosis and genetic susceptibility of herpes simplex encephalitis in children].

PubMed

Feng, Wenya; Chen, Tianming; Hu, Bing; Wan, Jiabin; Liu, Gang

2015-09-01

To summarize the clinical characteristics and long-term prognosis of herpes simplex virus encephalitis (HSE) in childhood and to analyze genotype of UNC93B1 and TLR3. Data of a total of 30 HSE patients admitted to Beijing Children's Hospital from January 2008 to September 2013 were retrospectively analyzed, the data included clinical manifestations, physical sign, auxiliary examination, therapy and long-term clinical prognosis. The family history obtained during follow-up visit was also analyzed for genetic predisposition. With parents' agreement, the blood specimens of patients were collected in EDTA anticoagulant tubes, the first 2 genetic etiologies UNC93B1 and TLR3 were sequenced, and the genetic susceptibility to HSE in childhood was summarized. (1) All the 30 patients (100%) had fever, 28 (93%) had seizure, 25 (83%) had altered state of consciousness, only 11 (37%) had personality changes, and in 8 (73%) appeared at or after 2 weeks of onset . (2) During the long-term follow up, 2 (7%) patients died after discharge, 23 patients (82%) had neurological sequelae, 13 patients (57%) had moderate, severe disability and vegetative state. (3) After sequencing of UNC93B1, and TLR3, one patient was found homozygous for a single-nucleotide substitution at position C.414C>G in exon 4 of UNC93B1 which affected the expression of UNC93B1, and may block or decrease the production of interferon. (4) Six single nucleotide polymorphisms (SNPs) were found in this study, their genotype frequency and gene frequency of Chinese were respectively searched in Genomes Project in NCBI and defined 1 000 genomes group. The genotype frequency of UNC93B1 rs7149 between 1 000 genomes group and HSE group was significantly different (χ² = 55.37, P<0.05). The frequency of CC type and C type was higher in HSE group, both of them had significant difference (χ² = 93.90, P<0.05, OR=61.563; χ² = 134.40, P<0.05, OR=12.491). HSE lacks specific clinical manifestations, the long-term prognosis is poor. One HSE patient carrying a heterozygous mutation in UNC93B1 which may lead to the susceptibility to HSE and had harmful effect on long-term prognosis. The SNP UNC93B1 rs7149 may also have relationship with susceptibility to HSE and the children carrying CC genotype or C gene in this gene site maybe more susceptible to HSE.

Acute and prolonged complement activation in the central nervous system during herpes simplex encephalitis.

PubMed

Eriksson, Charlotta E; Studahl, Marie; Bergström, Tomas

2016-06-15

Herpes simplex encephalitis (HSE) is characterized by a pronounced inflammatory activity in the central nervous system (CNS). Here, we investigated the acute and prolonged complement system activity in HSE patients, by using enzyme-linked immunosorbent assays (ELISAs) for numerous complement components (C). We found increased cerebrospinal fluid concentrations of C3a, C3b, C5 and C5a in HSE patients compared with healthy controls. C3a and C5a concentrations remained increased also compared with patient controls. Our results conclude that the complement system is activated in CNS during HSE in the acute phase, and interestingly also in later stages supporting previous reports of prolonged inflammation. Copyright © 2016 Elsevier B.V. All rights reserved.

Delivery of health surveillance for hand-arm vibration in the West Midlands.

PubMed

Kinoulty, Mary

2006-01-01

Concerns about provider competence and quality of hand-arm vibrations (HAVs) health surveillance programmes were identified by Health & Safety Executive (HSE) inspectors. To evaluate health surveillance programmes and compare them with published HSE guidance. To identify deficiencies and areas for improvement in the health surveillance programmes. A proforma was developed for the study and used on a sample of 10 local occupational health providers. All 10 organizations were aware of current HSE guidance for health surveillance for HAVs but only a minority (30%) were following it. Occupational health provider training, written procedures and health surveillance delivery were all identified as areas requiring improvement. The majority of organizations were not following HSE guidance. Occupational health providers undertaking health surveillance for HAV require specific training.

Effects of Decompressive Surgery on Prognosis and Cognitive Deficits in Herpes Simplex Encephalitis

PubMed Central

Midi, Ipek; Tuncer, Nese; Midi, Ahmet; Mollahasanoglu, Aynur; Konya, Deniz; Sav, Aydın

2007-01-01

Herpes simplex encephalitis (HSE) is a serious viral infection with a high rate of mortality. The most commonly seen complications are behavioral changes, seizures and memory deficits. We report the case of a 37-year-old man with HSE in the right temporal lobe and a severe midline shift who was treated with acyclovir. The patient underwent anterior temporal lobe resection. Although HSE can cause permanent cognitive deficits, in this case, early surgical intervention minimized any deficit, as determined by detailed neuropsychological examination. Surgical decompression is indicated as early as possible in severe cases. This case report emphasizes the effect of surgical decompression for HSE on cognitive function, which has rarely been mentioned before. PMID:18430984

Application of hazard and effects management tools and links to the HSE case

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gower-Jones, A.D.; Graaf, G.C. van der; Milne, D.J.

1996-12-31

Many tools and techniques are promoted for the analysis and management of hazards and their effects. The proliferation in the last 5-6 years of these tools has resulted in an overload on designers, engineers and operators of E&P activities and assets to the extent that they are unsure what to do when and how this fits together. This paper starts from the basic E&P business (a business model) the basic structure of any accidental event (bow tie) and maps the tools and techniques to analyze the hazards and effects for both asset and activity HSE management. The links to developingmore » an HSE case within the HSE-MS for assets and activities are given.« less

The HSE Management Standards Indicator Tool: concurrent and construct validity.

PubMed

Marcatto, F; Colautti, L; Larese Filon, F; Luis, O; Ferrante, D

2014-07-01

The Health & Safety Executive Management Standards Indicator Tool (HSE-MS IT) is a questionnaire commonly used to assess work-related stress risks at an organizational level. A critical factor in determining whether this instrument is actually useful is that higher levels of stress risk in the work-design domains should predict higher levels of stress and stress-related outcomes in workers. Only a few studies, however, have addressed this issue. To test both the concurrent and construct validity of the HSE-MS IT, by relating it with another widely used instrument, the Job Content Questionnaire (JCQ), and by examining its relationships with a set of work-related stress outcomes. An anonymous cross-sectional questionnaire was administered to a sample of employees in an Italian municipality. The questionnaire included the HSE-MS IT, self-reported measures of job satisfaction, job motivation and stress at work, the Satisfaction with Life Scale and the reduced form of the JCQ. A total of 760 out of 779 employees completed the questionnaire. Results showed moderate to strong correlation among the corresponding HSE-MS IT and JCQ scales. Hierarchical regression highlighted the specific contribution of each of the HSE-MS IT scales in predicting three relevant work-related stress outcomes (self-reported stress, job satisfaction and job motivation), after controlling for gender, age and life satisfaction. Our findings consolidated the HSE-MS IT validity and showed the specific sensitivity of its scales to assess different aspects of work-related distress, including self-perception of stress at work. These results can have practical implications for the occupational well-being of employees. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Evolution from safety management system (SMS) to HSE MS: Incorporating health aspects into the HSE management system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jong, G. de

1996-12-31

There is increasing recognition within the E&P industry that protection and promotion of the health of people at work is more than taking care of individual health. It is an organizational issue which can be managed using the same principles as for safety and environment. The synergy`s with safety and environmental management provide the link with the management system. However line managers need to under the critical Health issues: what are they are they relevant? How do we manage them? what are the standards? What are the management tools to be used? How do we monitor performance? What is themore » role of the line? What is the role of the health advisers? What training and competencies are needed for health management? What are the benefits? These questions have to be clarified before acceptance can be achieved for full integration of Health aspects into the HSE Management System. Health Risk Assessment was developed as a tool for systematic identification and assessment of health hazards and risks. It specifies the need for and type of controls and recovery measures, which can subsequently be incorporated in HSE Management System and HSE Cases. Our experience to date indicates that Health can successfully be integrated in HSE Management Systems and HSE Cases by using the same principles as developed for Safety Management Systems and Safety Cases. There are still many problems which need to be addressed but the methodology used appears to be sound and will eventually enhance line management understanding of the health management aspects relevant to the E&P Industry.« less

Efficacy of Economic Sanctions: North Korea and Iran Case Study

DTIC Science & Technology

2011-03-08

rate, as interpreted by Hufbauer, Schott, and Elliot ( HSE ), remained steady at thirty-four percent just as it had been since World War II. The end of...Germany, France, and Great Britain that diffused US economic power. HSE wrote: “The absence of an overriding global security threat made it harder for the...industrial countries to reconcile their different strategies and priorities for using sanctions in regional trouble spots.”8 In 1985 HSE published

Job stress: an in-depth investigation based on the HSE questionnaire and a multistep approach in order to identify the most appropriate corrective actions.

PubMed

De Sio, S; Cedrone, F; Greco, E; Di Traglia, M; Sanità, D; Mandolesi, D; Stansfeld, S A

2016-01-01

Psychosocial hazards and work-related stress have reached epidemic proportions in Europe. The Italia law introduced in 2008 the obligation for Italian companies to assess work related stress risk in order to protect their workers' safety and health. The purpose of our study was to propose an accurate measurement tool, using the HSE indicator tool, for more appropriate and significant work-related stress' prevention measures. The study was conducted on 204 visual display unit (VDU) operators: 106 male and 98 female. All subjects were administered the HSE questionnaire. The sample was studied through a 4 step process, using HSE analysis tool and a statistical analysis, based on the odds ratio calculation. The assessment model used demonstrated the presence of work related stress in VDU operators and additional "critical" aspects which had failed to emerge by the classical use of HSE analysis tool. The approach we propose allows to obtain a complete picture of the perception of work-related stress and can point out the most appropriate corrective actions.

Antifungal Effects of Saponin Extract from Rhizomes of Dioscorea panthaica Prain et Burk against Candida albicans

PubMed Central

Zhuang, Xinming; Feng, Xuechao

2018-01-01

Candida albicans is the most common fungal pathogen causing serious diseases, while there are only a paucity of antifungal drugs. Therefore, the present study was performed to investigate the antifungal effects of saponin extract from rhizomes of Dioscorea panthaica Prain et Burk (Huangshanyao Saponin extract, HSE) against C. albicans. HSE inhibits the planktonic growth and biofilm formation and development of C. albicans. 16–64 μg/mL of HSE could inhibit adhesion to polystyrene surfaces, transition from yeast to filamentous growth, and production of secreted phospholipase and could also induce endogenous reactive oxygen species (ROS) production and disrupt cell membrane in planktonic cells. Inhibitory activities against extracellular exopolysaccharide (EPS) production and ROS production in preformed biofilms could be inhibited by 64–256 μg/mL of HSE. Cytotoxicity against human Chang's liver cells is low, with a half maximal inhibitory concentration (IC50) of about 256 μg/mL. In sum, our study suggested that HSE might be used as a potential antifungal therapeutic against C. albicans. PMID:29853962

Navy Commercial Access Control System Did Not Effectively Mitigate Access Control Risks

DTIC Science & Technology

2013-09-16

fOR OFFICL’tb HSE OtuN Contents Introduction Objective 1 Background 1 Review of Internal Controls 4 Finding A. NCACS Did Not Effectively...8fHh’ DODIC.-20 13·134 I v FOR OFFICL’tb HSE ONI-X Introduction Objective The objective of the audit was to determine whether the Navy... HSE ONb\\’ authorized a Common Access Card. In order to avoid the appearance of endorsing Rapidgate, Eid Passport’s trademarked product, in May 2011

FEMA Urban Search and Rescue Teams: Considering an Improved Strategy for an Evolving Homeland Security Enterprise

DTIC Science & Technology

2012-09-01

and Rescue (US&R) teams be used more effectively and efficiently in the Homeland Security Enterprise ( HSE )? 1. Are there other strategies that would...allow the FEMA US&R resources to be more adaptable in the HSE ? 2. What other disciplines could be integrated with the FEMA US&R task forces to...consideration of the questions: 1. Can the FEMA US&R teams be used more effectively in the Homeland Security Enterprise ( HSE )? 2. Are there other

The Fractionation of Highly Siderophile Elements (HSE) in Impact Melts and the Determination of the Meteoritic Components

NASA Astrophysics Data System (ADS)

Schmidt, G.; Palme, H.; Kratz, K. L.

1995-09-01

Lunar highland rocks contain an excess of siderophile elements, which has been attributed to meteoritic influx after the formation of the lunar crust [1-4]. Siderophile element enrichment has subsequently become a standard method for the identification of terrestrial impact craters. Janssens et al. [5], Grieve [6] and Palme et al. [7] have shown the dominant role of impact melt as the main carrier of meteoritic material at large terrestrial impact craters. This has been demonstrated at Clearwater East [8], Lappajarvi [9-11], Saaksjarvi [12], Brent [6] and Rochechouart [5]. The amount of projectile material incorporated in impact melt sheets is generally low (<1%). The highest recorded is 8% at East Clearwater, where the siderophiles are carried in a sulphide phase. In other cases, searches for siderophile anomalies at some impact structure have been largely unsuccessful. Melt bearing mixed breccias (suevitic melt) and fall-back sediments have been found to be free of meteoritic components in Brent, Lappajarvi and Ries samples [6,9,12-14]. However, from approximately 130 craters which are currently known on Earth only four clearly identified chondrites have been found as projectiles of large craters [15,16]. In this study we analyzed twenty-two impact melt samples (10 g) from Saaksjarvi (Finland), Mien and Dellen (Sweden) impact craters for Os, Re, Ir, Ru, Rh, Pd and Au by a slightly modified version of the fire assay neutron activation method using nickel sulphide as the collector [13,14]. All samples were obtained from the collection of the University of Munster. Only fresh, nearly fragment-free, fine grained samples without any sign of alteration were selected for chemical studies. All samples have been described previously [17]. The INAA procedure involved two irradiations: a short irradiation for Rh and a long irradiation for the other elements. Impact melts from Saaksjarvi are highly enriched in PGEs. The flat siderophile pattern suggests that the meteoritic component (PGE/CI = 3x10^-3 to 9x10^-3 relative to CI) in the Saaksjarvi impact melt is relatively unfractionated. Stony-iron meteorites (pallasites) as proposed earlier [7] can therefore be excluded as possible contaminants because Pd and Ir are highly fractionated in pallasites [18]. Impact melts from Mien and Dellen are moderately enriched in PGE. The concentrations are similar (PGE/CI = 3x10^-4 to 1x10^-3 relative to CI). The flat siderophile pattern of the Mien and Dellen impact samples are compatible with carbonaceous chondrite type of material, but a clear geochemical association of any of the known meteorite types is not possible because of the low signal-to-background ratio for Rh, Ru, Pd, and Au. Samples from all impact craters have low Os/PGE ratios (Os/Ir(sub)melt =0.24) compared to chondritic ratios (Os/Ir(sub)CI=1.06). It seems that the oxygen fugacity at the time of impact melting, vaporization and crystallization of the melt body may play the dominant role in the fractionation of Os and PGEs. If Os have been partially lost by volatilization of OsO4 under oxidizing conditions, then Ir is the only element to confirm meteoritic enrichments down to a level of 2x10^-4 CI chondrite. None of the other elements determined are sufficiently sensitive indicators to confirm small meteoritic enrichments, equivalent to <10^-3 CI chondrite, because of low CI/Earth crust-ratios. Acknowledgements. This work was supported by DFG. References: [1] Wasson J. T. et al. (1975) Moon, 13, 121-141. [2] Gros J. et al. (1976) Proc. LSC 7th, 2403-2425. [3] Hertogen J. et al. (1977) Proc. LSC 8th, 17-45. [4] Palme H. (1980) Proc. LPSC 11th, 481-506. [5] Janssens M.-J. et al. (1977) JGR, 82, 750-758. [6] Grieve R. A. F. (1978) Proc. LPSC 9th, 2579-2608. [7] Palme H. et al. (1980) LPSC XI, 848-850. [8] Palme H. et al. (1978) GCA, 42, 313-323. [9] Reimold W. U. and Stoffler D. (1980) Meteoritics, 14, 526-528. [10] Reimold W. U. (1980) Ph. D. thesis, Univ. of Munster, 172 pp. [11] Gobel E. et al. (1980) Z. Naturforsch., 35a, 197-203. [12] Morgan J. W. et al. (1979) GCA, 43, 803-815. [13] Schmidt G. and Pernicka E. (1991) Meteoritics, 26, 392. [14] Schmidt G. and Pernicka E. (1994) GCA, 58, 5083-5090. [15] Palme H. et al. (1981) GCA, 45, 2417-2424. [16] Grieve R. A. F. (1991) Meteoritics, 26, 174-194. [17] Maerz U. (1979) Diploma thesis, Univ. of Munster, 115 pp. [18] Davis A. M. (1977) Ph. D. thesis, Yale University, 285 pp.

TLR3 deficiency in herpes simplex encephalitis: high allelic heterogeneity and recurrence risk.

PubMed

Lim, Hye Kyung; Seppänen, Mikko; Hautala, Timo; Ciancanelli, Michael J; Itan, Yuval; Lafaille, Fabien G; Dell, William; Lorenzo, Lazaro; Byun, Minji; Pauwels, Elodie; Rönnelid, Ylva; Cai, Xin; Boucherit, Soraya; Jouanguy, Emmanuelle; Paetau, Anders; Lebon, Pierre; Rozenberg, Flore; Tardieu, Marc; Abel, Laurent; Yildiran, Alisan; Vergison, Anne; Roivainen, Reina; Etzioni, Amos; Tienari, Pentti J; Casanova, Jean-Laurent; Zhang, Shen-Ying

2014-11-18

To determine the proportion of children with herpes simplex encephalitis (HSE) displaying TLR3 deficiency, the extent of TLR3 allelic heterogeneity, and the specific clinical features of TLR3 deficiency. We determined the sequence of all exons of TLR3 in 110 of the 120 patients with HSE enrolled in our study who do not carry any of the previously described HSE-predisposing mutations of TLR3 pathway genes (TLR3, UNC93B1, TRIF, TRAF3, and TBK1). All the new mutant TLR3 alleles detected were characterized experimentally in-depth to establish the causal relationship between the genotype and phenotype. In addition to the 3 previously reported TLR3-deficient patients from the same cohort, 6 other children or young adults with HSE carry 1 of 5 unique or extremely rare (minor allele frequency <0.001) missense TLR3 alleles. Two alleles (M374T, D592N) heterozygous in 3 patients are not deleterious in vitro. The other 3 are deleterious via different mechanisms: G743D+R811I and L360P heterozygous in 2 patients are loss-of-function due to low levels of expression and lack of cleavage, respectively, and R867Q homozygous in 1 patient is hypomorphic. The 3 patients' fibroblasts display impaired TLR3 responses and enhanced herpes simplex virus 1 susceptibility. Overall, TLR3 deficiency is therefore found in 6 (5%) of the 120 patients studied. There is high allelic heterogeneity, with 3 forms of autosomal dominant partial defect by negative dominance or haploinsufficiency, and 2 forms of autosomal recessive defect with complete or partial deficiency. Finally, 4 (66%) of the 6 TLR3-deficient patients had at least 1 late relapse of HSE, whereas relapse occurred in only 12 (10%) of the total cohort of 120 patients. Childhood-onset HSE is due to TLR3 deficiency in a traceable fraction of patients, in particular the ones with HSE recurrence. Mutations in TLR3 and TLR3 pathway genes should be searched and experimentally studied in children with HSE, and patients with proven TLR3 deficiency should be followed carefully. © 2014 American Academy of Neurology.

Long-term outcome of severe herpes simplex encephalitis: a population-based observational study.

PubMed

Jouan, Youenn; Grammatico-Guillon, Leslie; Espitalier, Fabien; Cazals, Xavier; François, Patrick; Guillon, Antoine

2015-09-21

Herpes simplex encephalitis (HSE) is a rare disease with a poor prognosis. No recent evaluation of hospital incidence, acute mortality and morbidity is available. In particular, decompressive craniectomy has rarely been proposed in cases of life-threatening HSE with temporal herniation, in the absence of evidence. This study aimed to assess the hospital incidence and mortality of HSE, and to evaluate the characteristics, management, the potential value of decompressive craniectomy and the outcome of patients with HSE admitted to intensive care units (ICUs). Epidemiological study: we used the hospital medical and administrative discharge database to identify hospital stays, deaths and ICU admissions relating to HSE in 39 hospitals, from 2010 to 2013. Retrospective monocentric cohort: all patients with HSE admitted to the ICU of the university hospital during the study were included. The use of decompressive craniectomy and long-term outcome were analyzed. The initial brain images were analyzed blind to outcome. The hospital incidence of HSE was 1.2/100,000 inhabitants per year, 32 % of the patients were admitted to ICUs and 17 % were mechanically ventilated. Hospital mortality was 5.5 % overall, but was as high as 11.9 % in ICUs. In the monocentric cohort, 87 % of the patients were still alive after one year but half of them had moderate to severe disability. Three patients had a high intracranial pressure (ICP) with brain herniation and eventually underwent decompressive hemicraniectomy. The one-year outcome of these patients did not seem to be different from that of the other patients. It was not possible to predict brain herniation reliably from the initial brain images. HSE appears to be more frequent than historically reported. The high incidence we observed probably reflects improvements in diagnostic performance (routine use of PCR). Mortality during the acute phase and long-term disability appear to be stable. High ICP and brain herniation are rare, but must be monitored carefully, as initial brain imaging is not useful for identifying high-risk patients. Decompressive craniectomy may be a useful salvage procedure in cases of intractable high ICP.

Anti-inflammatory effects of Houttuynia cordata supercritical extract in carrageenan-air pouch inflammation model

PubMed Central

Kim, Dajeong; Park, Dongsun; Kyung, Jangbeen; Yang, Yun-Hui; Choi, Ehn-Kyoung; Lee, Yoon-Bok; Kim, Hyun-Kyu; Hwang, Bang Yeon

2012-01-01

Anti-inflammatory effects of Houttuynia cordata supercritical extract (HSE) were investigated in rat carrageenan-air pouch model. Oral administration of HSE (50-200 mg/kg) suppressed carrageenan-induced exudation and albumin leakage, as well as inflammatory cell infiltration at a high dose (200 mg/kg). Intraperitoneal injection of dexamethasone (2 mg/kg) only decreased exudation and cell infiltration, while indomethacin (2 mg/kg, i.p.) reduced exudate volume and albumin content without influence on the cell number. HSE lowered tumor-necrosis factor-α (TNF-α) and nitric oxide (NO), as well as prostaglandin E2 (PGE2). Dexamethasone only reduced TNF-α and NO, while indomethacin decreased PGE2. The results indicate that HSE exhibits anti-inflammatory effects by inhibiting both TNF-α-NO and cyclooxygenase-2-PGE2 pathways. PMID:22787488

Mechanisms of the anti-hypertensive effect of Hibiscus sabdariffa L. calyces.

PubMed

Ajay, M; Chai, H J; Mustafa, A M; Gilani, A H; Mustafa, M R

2007-02-12

Previous studies have demonstrated the anti-hypertensive effects of Hibiscus sabdariffa L. (HS) in both humans and experimental animals. To explore the mechanisms of the anti-hypertensive effect of the HS, we examined the effects of a crude methanolic extract of the calyces of HS (HSE) on vascular reactivity in isolated aortas from spontaneously hypertensive rats. HSE relaxed, concentration-dependently, KCl (high K(+), 80 mM)- and phenylephrine (PE, 1 microM)-pre-contracted aortic rings, with a greater potency against the alpha(1)-adrenergic receptor agonist. The relaxant effect of HSE was partly dependent on the presence of a functional endothelium as the action was significantly reduced in endothelium-denuded aortic rings. Pretreatment with atropine (1 microM), L-NAME (10 microM) or methylene blue (10 microM), but not indomethacin (10 microM), significantly blocked the relaxant effects of HSE. Endothelium-dependent and -independent relaxations induced by acetylcholine and sodium nitroprusside, respectively, were significantly enhanced in aortic rings pretreated with HSE when compared to those observed in control aortic rings. The present results demonstrated that HSE has a vasodilator effect in the isolated aortic rings of hypertensive rats. These effects are probably mediated through the endothelium-derived nitric oxide-cGMP-relaxant pathway and inhibition of calcium (Ca(2+))-influx into vascular smooth muscle cells. The present data further supports previous in vivo findings and the traditional use of HS as an anti-hypertensive agent.

Implementing a tobacco-free hospital campus in Ireland: lessons learned.

PubMed

McArdle, D; Kabir, Z

2018-05-01

The Irish Health Service Executive (HSE) had set a target that all HSE facilities should implement the HSE Tobacco Free Campus (TFC) policy by 2015. The aims of this study are to examine hospital staff awareness and to assess the progress of selected HSE health care facilities towards a TFC policy. Three health care facilities that were conveniently located were self-selected in County Cork, namely, an acute hospital, a mental health service and an older person's facility. Three different types of quantitative data were collected between May and September 2016 drawn on Standards 3, 4 and 5 of the European Network for Tobacco Free Health Care Services (ENSH-Global) tools: (1) face-to-face consultation with health care facility managers on their progress towards the HSE TFC policy, (2) self-administered questionnaire to a purposive sample of 153 staff members across three health care facilities and (3) physical observation of signs of smoking and smoking-related information across each health care facility for objective verification of compliance. Of the 153 staff who completed the questionnaire, 64% were females, 39% were nurses, 20% were smokers and 76% agreed with the TFC policy. However, only 26% of the 153 staff had received training on motivational and tobacco cessation techniques. Seventy-seven percent of the 153 staff stated that the campus was not tobacco-free. Physical observation suggested signs of smoking within the campus across all three health care facilities surveyed. Staff awareness of the HSE TFC policy across selected health care facilities in Ireland is positive but is not sufficient. There are gaps in the implementation process of the HSE TFC policy in the health care facilities. Therefore, proper communication on the importance of the ENSH-Global standards and cessation training to all staff is necessary to help reduce smoking rates across the health care facilities and also to move towards a Tobacco Free Campus in Ireland.

Photoprotection by pistachio bioactives in a 3-dimensional human skin equivalent tissue model.

PubMed

Chen, C-Y Oliver; Smith, Avi; Liu, Yuntao; Du, Peng; Blumberg, Jeffrey B; Garlick, Jonathan

2017-09-01

Reactive oxygen species (ROS) generated during ultraviolet (UV) light exposure can induce skin damage and aging. Antioxidants can provide protection against oxidative injury to skin via "quenching" ROS. Using a validated 3-dimensional (3D) human skin equivalent (HSE) tissue model that closely mimics human skin, we examined whether pistachio antioxidants could protect HSE against UVA-induced damage. Lutein and γ-tocopherol are the predominant lipophilic antioxidants in pistachios; treatment with these compounds prior to UVA exposure protected against morphological changes to the epithelial and connective tissue compartments of HSE. Pistachio antioxidants preserved overall skin thickness and organization, as well as fibroblast morphology, in HSE exposed to UVA irradiation. However, this protection was not substantiated by the analysis of the proliferation of keratinocytes and apoptosis of fibroblasts. Additional studies are warranted to elucidate the basis of these discordant results and extend research into the potential role of pistachio bioactives promoting skin health.

Clinical outcomes in children with herpes simplex encephalitis receiving steroid therapy.

PubMed

Maraş Genç, Hülya; Uyur Yalçın, Emek; Sayan, Murat; Bayhan, Asuman; Öncel, Selim; Arısoy, Emin Sami; Kara, Bülent

2016-07-01

Herpes simplex virus encephalitis (HSE) is a significant cause of morbidity and mortality. Neurologic sequelae are common even after early initiation of acyclovir treatment. The host immune response during HSE can also lead to brain damage. There are an increasing number of reports favoring steroid use in HSE. We aimed to compare the prognosis of children with HSE with and without steroid therapy. We retrospectively screened our hospital archive from 2009 to 2014 for patients diagnosed with HSE with a positive result for herpes simplex virus polymerase chain reaction in cerebrospinal fluid. Patients ≥1 month and ≤18 years at diagnosis were included in the study. Clinical outcomes in terms of cognitive function, motor function, electroencephalographic findings, seizure frequency, and radiologic findings were compared in patients who received adjuvant steroid therapy with those who did not. Six patients (1 boy, 5 girls; aged 4 months to 10 years) were included. Overall symptom duration before hospital admission was ≤5days. Patients received acyclovir treatment for 21-28days. Three received steroid therapy early during the disease and three patients did not. No adverse effects related to steroids were observed. Follow-up duration was 6 months to 5 years. All patients had radiologic sequelae of encephalitis. Cognition, motor function, and seizure control were better in patients who received steroid therapy. Adjuvant steroid therapy seems to be effective in decreasing morbidity in children with HSE but the radiologic sequelae were the same in both groups. Copyright © 2016 Elsevier B.V. All rights reserved.

A strategic management model for evaluation of health, safety and environmental performance.

PubMed

Abbaspour, Majid; Toutounchian, Solmaz; Roayaei, Emad; Nassiri, Parvin

2012-05-01

Strategic health, safety, and environmental management system (HSE-MS) involves systematic and cooperative planning in each phase of the lifecycle of a project to ensure that interaction among the industry group, client, contractor, stakeholder, and host community exists with the highest level of health, safety, and environmental standard performances. Therefore, it seems necessary to assess the HSE-MS performance of contractor(s) by a comparative strategic management model with the aim of continuous improvement. The present Strategic Management Model (SMM) has been illustrated by a case study and the results show that the model is a suitable management tool for decision making in a contract environment, especially in oil and gas fields and based on accepted international standards within the framework of management deming cycle. To develop this model, a data bank has been created, which includes the statistical data calculated by converting the HSE performance qualitative data into quantitative values. Based on this fact, the structure of the model has been formed by defining HSE performance indicators according to the HSE-MS model. Therefore, 178 indicators have been selected which have been grouped into four attributes. Model output provides quantitative measures of HSE-MS performance as a percentage of an ideal level with maximum possible score for each attribute. Defining the strengths and weaknesses of the contractor(s) is another capability of this model. On the other hand, this model provides a ranking that could be used as the basis for decision making at the contractors' pre-qualification phase or during the execution of the project.

Test and demonstration of a 1-MW wellhead generator: helical screw expander power plant, Model 76-1. Final report to the International Energy Agency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1985-07-04

A 1-MW geothermal wellhead power plant incorporating a Lysholm or helical screw expander (HSE) was field tested between 1980 and 1983 by Mexico, Italy, and New Zealand with technical assistance from the United States. The objectives were to provide data on the reliability and performance of the HSE and to assess the costs and benefits of its use. The range of conditions under which the HSE was tested included loads up to 933 kW, mass flowrates of 14,600 to 395, 000 lbs/hr, inlet pressures of 64 to 220 psia, inlet qualities of 0 to 100%, exhaust pressures of 3.1 tomore » 40 psia, total dissolved solids up to 310,000 ppM, and noncondensible gases up to 38% of the vapor mass flow. Typical machine efficiencies of 40 to 50% were calculated. For most operations efficiency increased approximately logarithmically with shaft power, while inlet quality and rotor speed had only small effects. The HSE was designed with oversized internal clearances in the expectation that adherent scale would form during operation. Improvements in machine efficiency of 3.5 to 4 percentage points were observed over some test periods with some scale deposition. A comparison with a 1-MW back-pressure turbine showed that the HSE can compete favorably under certain conditions. The HSE was found to be a rugged energy conversion machine for geothermal applications, but some subsystems were found to require further development. 7 refs., 28 figs., 5 tabs.« less

A comparative study of the dentate gyrus in hippocampal sclerosis in epilepsy and dementia.

PubMed

Bandopadhyay, R; Liu, J Y W; Sisodiya, S M; Thom, M

2014-02-01

Hippocampal sclerosis (HS) is long-recognized in association with epilepsy (HSE ) and more recently in the context of cognitive decline or dementia in the elderly (HSD ), in some cases as a component of neurodegenerative diseases, including Alzheimer's disease (AD) and fronto-temporal lobe dementia (FTLD). There is an increased risk of seizures in AD and spontaneous epileptiform discharges in the dentate gyrus of transgenic AD models; epilepsy can be associated with an age-accelerated increase in AD-type pathology and cognitive decline. The convergence between these disease processes could be related to hippocampal pathology. HSE typically shows re-organization of both excitatory and inhibitory neuronal networks in the dentate gyrus, and is considered to be relevant to hippocampal excitability. We sought to compare the pathology of HSE and HSD , focusing on re-organization in the dentate gyrus. In nine post mortem cases with HSE and bilateral damage, 18 HSD and 11 controls we carried out immunostaining for mossy fibres (dynorphin), and interneuronal networks (NPY, calbindin and calretinin) on sections from the mid-hippocampal body. Fibre sprouting (FS) or loss of expression in the dentate gyrus was semi-quantitatively graded from grade 0 (normal) to grade 3 (marked alteration). Significantly more re-organization was seen with all four markers in the HSE than HSD group (P < 0.01). Mild alterations were noted in HSD group with dynorphin (FS in 3 cases), calretinin (FS in 6 cases), NPY (FS in 11 cases) and calbindin (loss in 10 cases). In eight HSD cases, alteration was seen with more than one antibody but in no cases were the highest grades seen. We also noted NPY and, to a lesser extent, calretinin labelling of Hirano bodies in CA1 of AD cases and some older controls, but not in HSE . Reorganization of excitatory and inhibitory networks in the dentate gyrus is more typical of HSE . Subtle alterations in HSD may be a result of increased hippocampal excitability, including unrecognized seizure activity. An unexpected finding was the identification of NPY-positive Hirano bodies in HSD but not HSE , which may be a consequence of the relative vulnerabilities of interneurons in these conditions. © 2013 The Authors. Neuropathology and Applied Neurobiology published by John Wiley & Sons Ltd on behalf of British Neuropathological Society.

A comparative study of the dentate gyrus in hippocampal sclerosis in epilepsy and dementia

PubMed Central

Bandopadhyay, R; Liu, J Y W; Sisodiya, S M; Thom, M

2014-01-01

Aims: Hippocampal sclerosis (HS) is long-recognized in association with epilepsy (HSE) and more recently in the context of cognitive decline or dementia in the elderly (HSD), in some cases as a component of neurodegenerative diseases, including Alzheimer's disease (AD) and fronto-temporal lobe dementia (FTLD). There is an increased risk of seizures in AD and spontaneous epileptiform discharges in the dentate gyrus of transgenic AD models; epilepsy can be associated with an age-accelerated increase in AD-type pathology and cognitive decline. The convergence between these disease processes could be related to hippocampal pathology. HSE typically shows re-organization of both excitatory and inhibitory neuronal networks in the dentate gyrus, and is considered to be relevant to hippocampal excitability. We sought to compare the pathology of HSE and HSD, focusing on re-organization in the dentate gyrus. Methods: In nine post mortem cases with HSE and bilateral damage, 18 HSD and 11 controls we carried out immunostaining for mossy fibres (dynorphin), and interneuronal networks (NPY, calbindin and calretinin) on sections from the mid-hippocampal body. Fibre sprouting (FS) or loss of expression in the dentate gyrus was semi-quantitatively graded from grade 0 (normal) to grade 3 (marked alteration). Results: Significantly more re-organization was seen with all four markers in the HSE than HSD group (P < 0.01). Mild alterations were noted in HSD group with dynorphin (FS in 3 cases), calretinin (FS in 6 cases), NPY (FS in 11 cases) and calbindin (loss in 10 cases). In eight HSD cases, alteration was seen with more than one antibody but in no cases were the highest grades seen. We also noted NPY and, to a lesser extent, calretinin labelling of Hirano bodies in CA1 of AD cases and some older controls, but not in HSE. Conclusion: Reorganization of excitatory and inhibitory networks in the dentate gyrus is more typical of HSE. Subtle alterations in HSD may be a result of increased hippocampal excitability, including unrecognized seizure activity. An unexpected finding was the identification of NPY-positive Hirano bodies in HSD but not HSE, which may be a consequence of the relative vulnerabilities of interneurons in these conditions. PMID:24028428

Improved CT Detection of Acute Herpes Simplex Virus Type 1 Encephalitis Based on a Frequency-Selective Nonlinear Blending: Comparison With MRI.

PubMed

Bongers, Malte Niklas; Bier, Georg; Ditt, Hendrik; Beck, Robert; Ernemann, Ulrike; Nikolaou, Konstantin; Horger, Marius

2016-11-01

The purpose of this study is to compare the diagnostic efficacy of a new CT postprocessing tool based on frequency-selective nonlinear blending (best-contrast CT) with that of standard linear blending of unenhanced head CT in patients with herpes simplex virus type 1 and herpes simplex virus encephalitis (HSE), using FLAIR MRI sequences as the standard of reference. Fifteen consecutive patients (six women and nine men; mean [± SD] age, 60 ± 19 years) with proven HSE (positive polymerase chain reaction results from CSF analysis and the presence of neurologic deficits) were retrospectively enrolled. All patients had undergone head CT and MRI (mean time interval, 2 ± 2 days). After standardized unenhanced head CT scans were read, presets of the best-contrast algorithm were determined (center, 30 HU; delta, 5 HU; slope, 5 nondimensional), and resulting images were analyzed. Contrast enhancement was objectively measured by ROI analysis, comparing contrast-to-noise ratios (CNRs) of unenhanced CT and best-contrast CT. FLAIR and DWI MRI sequences were analyzed, and FLAIR was considered as the standard of reference. For assessment of disease extent, a previously reported 50-point score (HSE score) was used. CNR values for unenhanced head CT (CNR, 5.42 ± 2.77) could be statistically significantly increased using best-contrast CT (CNR, 9.62 ± 4.28) (p = 0.003). FLAIR sequences yielded a median HSE score of 9.0 (range, 6-17) and DWI sequences yielded HSE scores of 6.0 (range, 5-17). By comparison, unenhanced head CT resulted in a median HSE score of 3.5 (range, 1-6). The median best-contrast CT HSE score was 7.5 (range, 6-10). Agreement between FLAIR and unenhanced CT was 54.44%, that between DWI and best-contrast CT was 95.36%, and that between FLAIR and best-contrast CT was 85.21%. The most frequently overseen findings were located at the level of the upper part of the mesencephalon and at the subthalamic or insular level. Frequency-selective nonlinear blending significantly increases contrast and detects brain parenchymal involvement in HSE more sensitively compared with unenhanced CT. The sensitivity of best-contrast CT seems to be equal to that of DWI and almost as good as that of FLAIR.

Health, safety and environmental unit performance assessment model under uncertainty (case study: steel industry).

PubMed

Shamaii, Azin; Omidvari, Manouchehr; Lotfi, Farhad Hosseinzadeh

2017-01-01

Performance assessment is a critical objective of management systems. As a result of the non-deterministic and qualitative nature of performance indicators, assessments are likely to be influenced by evaluators' personal judgments. Furthermore, in developing countries, performance assessments by the Health, Safety and Environment (HSE) department are based solely on the number of accidents. A questionnaire is used to conduct the study in one of the largest steel production companies in Iran. With respect to health, safety, and environment, the results revealed that control of disease, fire hazards, and air pollution are of paramount importance, with coefficients of 0.057, 0.062, and 0.054, respectively. Furthermore, health and environment indicators were found to be the most common causes of poor performance. Finally, it was shown that HSE management systems can affect the majority of performance safety indicators in the short run, whereas health and environment indicators require longer periods of time. The objective of this study is to present an HSE-MS unit performance assessment model in steel industries. Moreover, we seek to answer the following question: what are the factors that affect HSE unit system in the steel industry? Also, for each factor, the extent of impact on the performance of the HSE management system in the organization is determined.

Comparing the cognitive, personality and moral characteristics of high school and graduate medical entrants to the Tehran University of Medical Sciences in Iran.

PubMed

Nedjat, Saharnaz; Bore, Miles; Majdzadeh, Reza; Rashidian, Arash; Munro, Don; Powis, David; Karbakhsh, Mojgan; Keshavarz, Hossein

2013-12-01

Tehran University of Medical Sciences has two streams of medical student admission: an established high school entry (HSE) route and an experimental graduate entry (GE) route. To compare the cognitive skills, personality traits and moral characteristics of HSE and GE students admitted to this university. The personal qualities assessment tool (PQA; www.pqa.net.au ) was translated from English to Persian and then back-translated. Afterwards 35 individuals from the GE and 109 individuals from the 2007 to 2008 HSE completed the test. The results were compared by t-test and Chi-square. The HSE students showed significantly higher ability in the cognitive skills tests (p < 0.001). They were also more libertarian (p = 0.022), but had lower ability to confront stress and unpleasant events (p < 0.001), and had lower self-awareness and self-control (p < 0.001). On the basis of their personal qualities, the GE students had more self-control and strength when coping with stress than the HSE students, but the latter had superior cognitive abilities. Hence it may be useful to include cognitive tests in GE students' entry exam and include tests of personal qualities to exclude those with unsuitable characteristics.

Presenting a conceptual pattern of HSE performance of oil trucks.

PubMed

Ghaleh, Sahar; Omidvari, Manouchehr; Nassiri, Parvin; Momeni, Mansour; Lavasani, Seyed Mohammadreza Miri

2018-01-25

Accidents are among the main problems in the oil product supply chain. The most important effective factors in these events are the kind of trucks used and their health, safety, and environment (HSE) condition. The aim of this study was to present a conceptual pattern of the HSE performance of oil trucks in oil industries. In this study, 20 truck models (with fixed tanks), in use over different periods of time, were investigated. In this regard, the criteria and sub-criteria were first determined in two parts-carrier and tank-and weighted by fuzzy analytical hierarchy process (FAHP). The results showed that the most important sub-criteria regarding the HSE factors of the carrier were resistance and strength of the front and rear shields, the brake system, and the ventilation system. The most important sub-criteria regarding the HSE factors of the tank were tank shell thickness and a good tank design shape with respect to portable material. It should be noted that the weight of the criteria with each other and sub-criteria with each other are not equal. This issue is important for decision-making. The main reason for the use of trucks with the lowest score in developing countries is the lack of attention by managers to safety issues and international standards and agreements such as the ADR.

Molecular cloning of an inducible serine esterase gene from human cytotoxic lymphocytes.

PubMed Central

Trapani, J A; Klein, J L; White, P C; Dupont, B

1988-01-01

A cDNA clone encoding a human serine esterase gene was isolated from a library constructed from poly(A)+ RNA of allogeneically stimulated, interleukin 2-expanded peripheral blood mononuclear cells. The clone, designated HSE26.1, represents a full-length copy of a 0.9-kilobase mRNA present in human cytotoxic cells but absent from a wide variety of noncytotoxic cell lines. Clone HSE26.1 contains an 892-base-pair sequence, including a single 741-base-pair open reading frame encoding a putative 247-residue polypeptide. The first 20 amino acids of the polypeptide form a leader sequence. The mature protein is predicted to have an unglycosylated Mr of approximately equal to 26,000 and contains a single potential site for N-linked glycosylation. The nucleotide and predicted amino acid sequences of clone HSE26.1 are homologous with all murine and human serine esterases cloned thus far but are most similar to mouse granzyme B (70% nucleotide and 68% amino acid identity). HSE26.1 protein is expressed weakly in unstimulated peripheral blood mononuclear cells but is strongly induced within 6-hr incubation in medium containing phytohemagglutinin. The data suggest that the protein encoded by HSE26.1 plays a role in cell-mediated cytotoxicity. Images PMID:3261871

Using the HSE stress indicator tool in a military context.

PubMed

Bridger, Robert S; Dobson, Karen; Davison, Hannah

2016-01-01

An assessment of the Health and Safety Executive's (HSE) stress indicator tool was conducted to determine whether it was suitable for use with Ministry of Defence (MoD) personnel. A total of 1031 respondents from the Army, Navy, Air Force and MoD civilians completed a questionnaire containing the HSE tool and supplementary measures of work-life balance, engagement, deployment, leave taken and hours of work. Six measures of adverse reaction to the stressors were also reported: perceptions of job stress, job stress and health, psychological strain, fatigue after work, work ability and quality of working life. The stressor scales, particularly the 'demands' and 'relationships' scales, were associated with adverse outcomes as was the work-life balance scale. The HSE tool had some validity when used with MoD personnel, but its content was too narrow. The content validity of the tool can be improved for use in a military context with the addition of a 'work-life balance' scale'. The HSE stress tool was tested with a mixed sample of MoD employees. The ‘Demands and “Relationships” scales were associated with adverse outcomes. An additional Work–Life Balance’ scale improved the content validity, demonstrating the importance of assessing the psychometric qualities of scales when used within particular contexts to ensure validity.

Reduction of elemental selenium to selenide: Experiments with anoxic sediments and bacteria that respire Se-oxyanions

USGS Publications Warehouse

Herbel, M.J.; Blum, J.S.; Oremland, R.S.; Borglin, S.E.

2003-01-01

A selenite-respiring bacterium, Bacillus selenitireducens, produced significant levels of Se(-II) (as aqueous HSe-) when supplied with Se(O). B. selenitireducens was also able to reduce selenite [Se(IV)] through Se(O) to Se(-II). Reduction of Se(O) by B.selenitireducens was more rapid in cells grown on colloidal sulfur [S(O)] or Se(IV) as their electron acceptor than for cell lines grown on fumarate. In contrast, three cultures of selenate-respiring bacteria, Sulfurospirillum barnesii, B. arsenicoselenatis, and Selenihalanaerobacter shriftii either were unable to reduce Se(O) to Se(-II) or had only a very limited capacity to achieve this reduction. Biological reduction of Se(O) to Se(-II) was observed during incubation of estuarine sediment slurries, while no such activity was noted in formalin-killed controls. The majority of the Se(-II) produced was found in the sediments as a solid precipitate of FeSe, rather than in solution as HSe-. These results demonstrate that certain anaerobic bacteria have the capacity to reduce Se(O) to Se(-II), providing a possible biological explanation for the occurrence of the selenide species in some sedimentary rocks.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Munganahalli, D.

Sedco Forex is a drilling contractor that operates approximately 80 rigs on land and offshore worldwide. The HSE management system developed by Sedco Forex is an effort to prevent accidents and minimize losses. An integral part of the HSE management system is establishing risk profiles and thereby minimizing risk and reducing loss exposures. Risk profiles are established based on accident reports, potential accident reports and other risk identification reports (RIR) like the Du Pont STOP system. A rig could fill in as many as 30 accident reports, 30 potential accident reports and 500 STOP cards each year. Statistics are importantmore » for an HSE management system, since they are indicators of success or failure of HSE systems. It is however difficult to establish risk profiles based on statistical information, unless tools are available at the rig site to aid with the analysis. Risk profiles are then used to identify important areas in the operation that may require specific attention to minimize the loss exposure. Programs to address the loss exposure can then be identified and implemented with either a local or corporate approach. In January 1995, Sedco Forex implemented a uniform HSE Database on all the rigs worldwide. In one year companywide, the HSE database would contain information on approximately 500 accident and potential accident reports, and 10,000 STOP cards. This paper demonstrates the salient features of the database and describes how it has helped in establishing key risk profiles. It also shows a recent example of how risk profiles have been established at the corporate level and used to identify the key contributing factors to hands and finger injuries. Based on this information, a campaign was launched to minimize the frequency of occurrence and associated loss attributed to hands and fingers accidents.« less

A safety management system for an offshore Azerbaijan Caspian Sea Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brasic, M.F.; Barber, S.W.; Hill, A.S.

1996-11-01

This presentation will describe the Safety Management System that Azerbaijan International Operating Company (AIOC) has structured to assure that Company activities are performed in a manner that protects the public, the environment, contractors and AIOC employees. The Azerbaijan International Oil Company is a consortium of oil companies that includes Socar, the state oil company of Azerbaijan, a number of major westem oil companies, and companies from Russia, Turkey and Saudi Arabia. The Consortium was formed to develop and produce a group of large oil fields in the Caspian Sea. The Management of AIOC, in starting a new operation in Azerbaijan,more » recognized the need for a formal HSE management system to ensure that their HSE objectives for AIOC activities were met. As a consortium of different partners working together in a unique operation, no individual partner company HSE Management system was appropriate. Accordingly AIOC has utilized the E & P Forum {open_quotes}Guidelines for the Development and Application of Health Safety and Environmental Management Systems{close_quotes} as the framework document for the development of the new AIOC system. Consistent with this guideline, AIOC has developed 19 specific HSE Management System Expectations for implementing its HSE policy and objectives. The objective is to establish and continue to maintain operational integrity in all AIOC activities and site operations. An important feature is the use of structured Safety Cases for the design engineering activity. The basis for the Safety Cases is API RP 75 and 14 J for offshore facilities and API RP 750 for onshore facilities both complimented by {open_quotes}Best International Oilfield Practice{close_quotes}. When viewed overall, this approach provides a fully integrated system of HSE management from design into operation.« less

The new role of HSE in chemical product development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Purinton, R.J. Jr.; Manning, T.S.; Dowell, S.

1996-11-01

Today, Health, Safety, and Environmental issues take a more prominent role than ever before in chemical product development for the global oilfield service industry. Prior to widespread regulatory guidelines, technical problems were solved and well treatment programs were developed using the chemicals which performed the best and were the least expensive for the application. HSE concerns were sometimes addressed from a remedial standpoint, rather than a preventive one throughout the process. With a clearer understanding of the potential impact of chemicals upon people and the environment, along with the ever-increasing array of government regulations, service companies are taking a newmore » approach to product development. HSE-related risks and costs are being assessed early and continued throughout chemical development, with both product and treatment process features then designed accordingly. One service company reflects this approach with its {open_quotes}cradle-to-grave{close_quotes} Product Development and Stewardship program. Integral to this program are planned HSE assessments at each step of development, including Feasibility, Lab Development, Field Testing, Manufacturing, and Commercial Field Introduction. These assessments provide the data necessary to {open_quotes}engineer-in{close_quotes} solutions to potential HSE-related problems, produce viable Risk Management Plans, and promote a smoother path to commercialization. This avoids arriving at the commercial launch point with a product which poses unacceptably high personal or environmental risks, may be restricted or banned in key markets, or requires lengthy and expensive government registrations. In order to optimize R&E resources and ensure continuous evaluation, decision points (to continue, modify, or abandon) are built into the process. Early HSE screenings must be accurate but also relatively quick and inexpensive to be meaningful and economical.« less

A partnership in upstream HSE technology transfer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olszewski, R.E. Wahjosoedibjo, A.S.; Hunley, M.; Peargin, J.C.

1996-11-01

The oil and gas industry was for nearly two decades the dominant force in the Indonesian economy and the single largest contributor to the nation`s development. Because of the success of Indonesia`s long-term development and diversification program, this once-dominant sector today occupies a more equal but still vital position in a better-balanced economy. The Indonesian government understands the danger to the environment posed by rapid industrial expansion and has enacted laws and regulations to ensure the sustainable development of its resources while protecting its rain forest environment. In 1992, the government oil company approached Chevron and Texaco for assistance inmore » training its Health, Safety, and Environment (HSE) professionals. The upstream environment, health and safety training program was developed to transfer HSE knowledge and technology to PERTAMINA, PT Caltex Pacific Indonesia, a C&T affiliate, and indirectly, to the entire Indonesian oil and gas industry and government ministries. The four companies have demonstrated the effectiveness of a partnership approach in developing and carrying out HSE training. During 1994 and 1995, four groups, each consisting of about twenty representatives from PERTAMINA, the Directorate of Oil and Gas (MIGAS), the Indonesian Environmental Impact Management Agency (BAPEDAL), CPI, and Chevron and Texaco worldwide subsidiaries, traveled to the United States for an intensive four-month program of study in HSE best practices and technology conducted by Chevron and Texaco experts. This paper describes the development and realization of The PERTAMINA/CPI Health, Safety and Environment Training Program, outlines subjects covered and explains the methodology used to ensure the effective transfer of HSE knowledge and technology. The paper also offers an evaluation of the sessions and presents the plans developed by participant-teams for follow up on their return to Indonesia.« less

Framework for Evaluating Educational Systemic Initiatives.

ERIC Educational Resources Information Center

Ikegulu, T. Nelson

This paper describes the implementation of the Holistic Systemic Evaluation (HSE), a component of an Education Systemic Initiative's strategic management. The HSE provides general guidance for the implementation and continual improvement of an Education Systemic Initiative Reform (ESIR). The implementation of the education system initiative plan:…

HSE's safety assessment principles for criticality safety.

PubMed

Simister, D N; Finnerty, M D; Warburton, S J; Thomas, E A; Macphail, M R

2008-06-01

The Health and Safety Executive (HSE) published its revised Safety Assessment Principles for Nuclear Facilities (SAPs) in December 2006. The SAPs are primarily intended for use by HSE's inspectors when judging the adequacy of safety cases for nuclear facilities. The revised SAPs relate to all aspects of safety in nuclear facilities including the technical discipline of criticality safety. The purpose of this paper is to set out for the benefit of a wider audience some of the thinking behind the final published words and to provide an insight into the development of UK regulatory guidance. The paper notes that it is HSE's intention that the Safety Assessment Principles should be viewed as a reflection of good practice in the context of interpreting primary legislation such as the requirements under site licence conditions for arrangements for producing an adequate safety case and for producing a suitable and sufficient risk assessment under the Ionising Radiations Regulations 1999 (SI1999/3232 www.opsi.gov.uk/si/si1999/uksi_19993232_en.pdf).

Preparedness of elderly long-term care facilities in HSE East for influenza outbreaks.

PubMed

O'Connor, L; Boland, M; Murphy, H

2015-01-01

Abstract We assessed preparedness of HSE East elderly long-term care facilities for an influenza outbreak, and identified Public Health Department support needs. We surveyed 166 facilities based on the HSE checklist document for influenza outbreaks, with 58% response rate. Client flu vaccination rates were > 75%; leading barriers were client anxiety and consent issues. Target flu vaccine uptake of 40% in staff occurred in 43% of facilities and was associated with staff vaccine administration by afacility-attached GP (p = 0.035), having a facility outbreak plan (p = 0.013) and being anon-HSE run facility (p = 0.013). Leading barriers were staff personal anxiety (94%) and lack of awareness of the protective effect on clients (21%). Eighty-nine percent found Public Health helpful, and requested further educational support and advocacy. Staff vaccine uptake focus, organisational leadership, optimal vaccine provision models, outbreak plans and Public Health support are central to the influenza campaign in elderly long-term care facilities.

Band gap bowing and crossing of BxGa1-xN alloy investigated by hybrid functional method

NASA Astrophysics Data System (ADS)

Jiaping, Jiang; Yanqin, Gai; Gang, Tang

2016-02-01

The electronic properties of zinc-blende BxGa1-xN alloys are comparatively investigated by employing both the Perdewe-Burkee-Ernzerhof generalized-gradient approximation (PBE-GGA) and the Heyd-Scuseria-Ernzerhof screened hybrid functional methods (HSE06). HSE06 reproduced much closer ground-state properties to experiments. Large and composition-dependent bowing parameters bγ for the direct band gaps were obtained from both PBE and HSE06. The crossover composition where alloy switches from direct to indirect was predicted to occur at very similar x from PBE and HSE06. We can obtain direct gap BxGa1-xN with a gap value much larger than that of GaN by alloying x < 0.557 boron into GaN. Project supported by the Fundamental Research Funds for the Central Universities (No. 2010LKWL03), the Special Fund for Theoretical Physics (No. 11047130), and the National Natural Science Foundation of China (No. 11104345).

Do people with low self-esteem really want to feel better? Self-esteem differences in motivation to repair negative moods.

PubMed

Heimpel, Sara A; Wood, Joanne V; Marshall, Margaret A; Brown, Jonathon D

2002-01-01

This research examined the hypothesis that people with low self-esteem (LSE) are less motivated than people with high self-esteem (HSE) to repair their negative moods. In Study 1, participants completed diaries in response to either a success or a failure in their everyday lives. Participants described what they intended to do next and the reasons behind those plans. After failure, fewer LSE than HSE participants expressed a goal to improve their mood. A follow-up investigation (Study 2) suggested that this difference was not due to a self-esteem difference in knowledge of mood repair strategies. In Study 3, after undergoing a negative mood induction, fewer LSE than HSE participants chose to watch a comedy video, even though both groups believed the comedy video would make them happy. Studies 4 and 5 explored possible reasons why LSE people are less motivated than HSE people to repair their negative moods.

Herpes simplex virus-induced anti-N-methyl-d-aspartate receptor encephalitis: a systematic literature review with analysis of 43 cases.

PubMed

Nosadini, Margherita; Mohammad, Shekeeb S; Corazza, Francesco; Ruga, Ezia Maria; Kothur, Kavitha; Perilongo, Giorgio; Frigo, Anna Chiara; Toldo, Irene; Dale, Russell C; Sartori, Stefano

2017-08-01

To conduct a systematic literature review on patients with biphasic disease with herpes simplex virus (HSV) encephalitis followed by anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. We conducted a case report and systematic literature review (up to 10 December 2016), focused on differences between herpes simplex encephalitis (HSE) and anti-NMDAR encephalitis phases, age-related characteristics of HSV-induced anti-NMDAR encephalitis, and therapy. For statistical analyses, McNemar's test, Fisher's test, and Wilcoxon rank sum test were used (two-tailed significance level set at 5%). Forty-three patients with biphasic disease were identified (31 children). Latency between HSE and anti-NMDAR encephalitis was significantly shorter in children than adults (median 24 vs 40.5d; p=0.006). Compared with HSE, anti-NMDAR encephalitis was characterized by significantly higher frequency of movement disorder (2.5% vs 75% respectively; p<0.001), and significantly lower rate of seizures (70% vs 30% respectively; p=0.001). Compared with adults, during anti-NMDAR encephalitis children had significantly more movement disorders (86.7% children vs 40% adults; p=0.006), fewer psychiatric symptoms (41.9% children vs 90.0% adults; p=0.025), and a slightly higher median modified Rankin Scale score (5 in children vs 4 in adults; p=0.015). During anti-NMDAR encephalitis, 84.6 per cent of patients received aciclovir (for ≤7d in 22.7%; long-term antivirals in 18.0% only), and 92.7 per cent immune therapy, but none had recurrence of HSE clinically or using cerebrospinal fluid HSV polymerase chain reaction (median follow-up 7mo). Our review suggests that movement disorder may help differentiate clinically an episode of HSV-induced anti-NMDAR encephalitis from HSE relapse. Compared with adults, children have shorter latency between HSE and anti-NMDAR encephalitis and, during anti-NMDAR encephalitis, more movement disorder, fewer psychiatric symptoms, and slightly more severe disease. According to our results, immune therapy given for HSV-induced anti-NMDAR encephalitis does not predispose patients to HSE recurrence. © 2017 Mac Keith Press.

HSE inspector advises on 'common mistakes'.

PubMed

Baillie, Jonathan

2012-10-01

A recent IHEEM seminar on water hygiene and safety, 'The Invisible Threat', saw John Newbold, an HM specialist inspector at the Health and Safety Executive (HSE) with experience investigating Legionella cases and outbreaks, provide useful insight into how healthcare estates engineers and other 'responsible' personnel could ensure compliance with the law by properly 'managing and controlling' Legionella risk. He provided a first-hand view of what he dubbed 'some of the common mistakes' made by those responsible for managing water system safety, and gave useful advice and guidance on how to avoid them, and thus minimise the risk of falling foul of the HSE and other regulators. HEJ editor, Jonathan Baillie, reports.

Genomic Heat Shock Element Sequences Drive Cooperative Human Heat Shock Factor 1 DNA Binding and Selectivity*

PubMed Central

Jaeger, Alex M.; Makley, Leah N.; Gestwicki, Jason E.; Thiele, Dennis J.

2014-01-01

The heat shock transcription factor 1 (HSF1) activates expression of a variety of genes involved in cell survival, including protein chaperones, the protein degradation machinery, anti-apoptotic proteins, and transcription factors. Although HSF1 activation has been linked to amelioration of neurodegenerative disease, cancer cells exhibit a dependence on HSF1 for survival. Indeed, HSF1 drives a program of gene expression in cancer cells that is distinct from that activated in response to proteotoxic stress, and HSF1 DNA binding activity is elevated in cycling cells as compared with arrested cells. Active HSF1 homotrimerizes and binds to a DNA sequence consisting of inverted repeats of the pentameric sequence nGAAn, known as heat shock elements (HSEs). Recent comprehensive ChIP-seq experiments demonstrated that the architecture of HSEs is very diverse in the human genome, with deviations from the consensus sequence in the spacing, orientation, and extent of HSE repeats that could influence HSF1 DNA binding efficacy and the kinetics and magnitude of target gene expression. To understand the mechanisms that dictate binding specificity, HSF1 was purified as either a monomer or trimer and used to evaluate DNA-binding site preferences in vitro using fluorescence polarization and thermal denaturation profiling. These results were compared with quantitative chromatin immunoprecipitation assays in vivo. We demonstrate a role for specific orientations of extended HSE sequences in driving preferential HSF1 DNA binding to target loci in vivo. These studies provide a biochemical basis for understanding differential HSF1 target gene recognition and transcription in neurodegenerative disease and in cancer. PMID:25204655

Consumption of Hibiscus sabdariffa L. aqueous extract and its impact on systemic antioxidant potential in healthy subjects.

PubMed

Frank, Thomas; Netzel, Gabriele; Kammerer, Dietmar R; Carle, Reinhold; Kler, Adolf; Kriesl, Erwin; Bitsch, Irmgard; Bitsch, Roland; Netzel, Michael

2012-08-15

To evaluate health benefits attributed to Hibiscus sabdariffa L. a randomized, open-label, two-way crossover study was undertaken to compare the impact of an aqueous H. sabdariffa L. extract (HSE) on the systemic antioxidant potential (AOP; assayed by ferric reducing antioxidant power (FRAP)) with a reference treatment (water) in eight healthy volunteers. The biokinetic variables were the areas under the curve (AUC) of plasma FRAP, ascorbic acid and urate that are above the pre-dose concentration, and the amounts excreted into urine within 24 h (Ae(0-24) ) of antioxidants as assayed by FRAP, ascorbic acid, uric acid, malondialdehyde (biomarker for oxidative stress), and hippuric acid (metabolite and potential biomarker for total polyphenol intake). HSE caused significantly higher plasma AUC of FRAP, an increase in Ae(0-24) of FRAP, ascorbic acid and hippuric acid, whereas malondialdehyde excretion was reduced. Furthermore, the main hibiscus anthocyanins as well as one glucuronide conjugate could be quantified in the volunteers' urine (0.02% of the administered dose). The aqueous HSE investigated in this study enhanced the systemic AOP and reduced the oxidative stress in humans. Furthermore, the increased urinary hippuric acid excretion after HSE consumption indicates a high biotransformation of the ingested HSE polyphenols, most likely caused by the colonic microbiota. Copyright © 2012 Society of Chemical Industry.

Bacterial contamination of the lacteal contents of feeding bottles in metropolitan São Paulo, Brazil.

PubMed Central

Morais, T. B.; Morais, M. B.; Sigulem, D. M.

1998-01-01

Reported are the results of a study in São Paulo, Brazil, to evaluate the bacterial contamination of the lacteal contents of feeding bottles prepared in urban households of low (LSE) and high (HSE) socioeconomic groups, involving 100 and 32 mothers of infants, respectively. Samples of the lacteal contents of the feeding bottles were cultured and the medians (25th and 75th percentiles) of the counts (bacteria per ml) were significantly higher in the LSE group: mesophilic bacteria, 555,000 (17,250-4,350,000) in the LSE group and 1615 (20-500,000) in the HSE group; coliforms, 2400 (19-150,000) in the LSE group and 7 (0-7800) in the HSE group. Escherichia coli was isolated from 26% (26/100) of the samples from the LSE group and from 6% (2/32) of those from the HSE group (P = 0.03). In the HSE group, higher coliform counts were associated with foodhandlers other than the mother, lower levels of maternal education, the use of pasteurized milk, and the addition of ingredients other than milk. In the LSE group, feeding bottles prepared using tap water and those prepared for infants aged over 6 months had higher coliform counts. In general, the feeding bottles prepared in the households studied were heavily contaminated, especially in the LSE group. PMID:9648358

Combined hybrid functional and DFT+U calculations for metal chalcogenides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aras, Mehmet; Kılıç, Çetin, E-mail: cetin-kilic@gyte.edu.tr

2014-07-28

In the density-functional studies of materials with localized electronic states, the local/semilocal exchange-correlation functionals are often either combined with a Hubbard parameter U as in the LDA+U method or mixed with a fraction of exactly computed (Fock) exchange energy yielding a hybrid functional. Although some inaccuracies of the semilocal density approximations are thus fixed to a certain extent, the improvements are not sufficient to make the predictions agree with the experimental data. Here, we put forward the perspective that the hybrid functional scheme and the LDA+U method should be treated as complementary, and propose to combine the range-separated Heyd-Scuseria-Ernzerhof (HSE)more » hybrid functional with the Hubbard U. We thus present a variety of HSE+U calculations for a set of II-VI semiconductors, consisting of zinc and cadmium monochalcogenides, along with comparison to the experimental data. Our findings imply that an optimal value U{sup *} of the Hubbard parameter could be determined, which ensures that the HSE+U{sup *} calculation reproduces the experimental band gap. It is shown that an improved description not only of the electronic structure but also of the crystal structure and energetics is obtained by adding the U{sup *} term to the HSE functional, proving the utility of HSE+U{sup *} approach in modeling semiconductors with localized electronic states.« less

Lunar and Planetary Science XXXV: Concerning Chondrites

NASA Technical Reports Server (NTRS)

2004-01-01

The Lunar and Planetary Science XXXV session entitled "Concerning Chondrites" includes the following topics: 1) Petrology and Raman Spectroscopy of Shocked Phases in the Gujba CB Chondrite and the Shock History of the CB Parent Body; 2) The Relationship Between CK and CV Chondrites: A Single Parent Body Source? 3) Samples of Asteroid Surface Ponded Deposits in Chondritic Meteorites; 4) Composition and Origin of SiO2-rich Objects in Carbonaceous and Ordinary Chondrites; 5) Re-Os Systematics and HSE distribution in Tieschitz (H3.6); Two Isochrons for One Meteorite; 6) Loss of Chromium from Olivine During the Metamorphism of Chondrites; 7) Very Short Delivery Times of Meteorites After the L-Chondrite Parent Body Break-Up 480 Myr Ago; and 8) The Complex Exposure History of a Very Large L/LL5 Chondrite Shower: Queen Alexandra Range 90201.

Socioeconomic Outcomes from Adult Education.

ERIC Educational Resources Information Center

Gooderham, Paul N.

1991-01-01

The degree to which age and gender influence completion of higher secondary education (HSE) and employment status was measured with a sample of 350 Norwegian adults. Application of a Status Attainment model revealed that post-HSE educational attainment is an important determinant of socioeconomic status for both men and women. (SK)

Counterintelligence Screening Needed lo Reduce Security Threat That Unscreened Local National Linguists Pose to U.S. Forces (REDACTED)

DTIC Science & Technology

2012-12-07

Commander, U.S. Forces- Afghanistan -- - ·--·- --· I A., B. l., and B.2. FOR OFFICl/rlJ BSE O:PflrlI ii F0R 0FFiCM-L HSE 0Nhi’ Table of...Our Response 13 Appendices A. Scope and Methodology 15 Use of Computer Processed Data 16 Prior Coverage 16 1 F0R 0FFiCIA±i HSE 0Nl-J’l F61t...security screening process for escorted entry while on U.S. Forces’ installations in Afghanistan. FOR 0ff’ICikb HSE 0"Pfb Y 5 F6:K 6FFl€1A:b ffl

Noble metal abundances in komatiite suites from Alexo, Ontario and Gorgona Island, Colombia

NASA Astrophysics Data System (ADS)

Brügmann, G. E.; Arndt, N. T.; Hofmann, A. W.; Tobschall, H. J.

1987-08-01

The distribution of the chalcophile and siderophile metals Cu, Ni, Au, Pd, Ir, Os and Ru in an Archaean komatiite flow from Alexo, Ontario and in a Phanerozoic komatiitic suite of Gorgona Island, Colombia, provides new information about the geochemical behaviour of these elements. Copper, Au and Pd behave as incompatible elements during the crystallization of these ultramafic magmas. In contrast, Ni, Ir, Os and Ru concentrations systematically decrease with decreasing MgO contents, a pattern characteristic of compatible elements. These trends are most probably controlled by olivine crystallization, which implies that Ir, Os and Ru are compatible in olivine. Calculated partition coefficients for Ir, Os and Ru between olivine and the melt are about 1.8. Compared to primitive mantle, parental komatiitic liquids are enriched in (incompatible) Cu, Au and Pd and depleted in (compatible) Ir, Os and Ru. Within both Archaean and Phanerozoic komatiites, noble metal ratios such as Au/Pd, Ir/Os, Os/Ru and Ru/Ir and ratios of lithophile and siderophile elements such as Ti/Pd, Ti/Au are constant and similar to primitive mantle values. This implies that Au and Pd are moderately incompatible elements and that there has been no significant fractionation of siderophile and lithophile elements since the Archaean. Platinum-group element abundances of normal MORB are highly variable and always much lower than in komatiites, because MORB magma is saturated with sulfur and a variable but minor amount of sulfide segregated during mantle melting or during the ascent of magma to the surface. Sulfide deposits associated with komatiites display similar chalcophile element patterns to those of komatiites. Noble metal ratios such as Pd/Ir, Au/Ir, Pd/Os and Pd/Ru can be used to determine the composition of the host komatiite at the time of sulfide segregation.

When Density Functional Approximations Meet Iron Oxides.

PubMed

Meng, Yu; Liu, Xing-Wu; Huo, Chun-Fang; Guo, Wen-Ping; Cao, Dong-Bo; Peng, Qing; Dearden, Albert; Gonze, Xavier; Yang, Yong; Wang, Jianguo; Jiao, Haijun; Li, Yongwang; Wen, Xiao-Dong

2016-10-11

Three density functional approximations (DFAs), PBE, PBE+U, and Heyd-Scuseria-Ernzerhof screened hybrid functional (HSE), were employed to investigate the geometric, electronic, magnetic, and thermodynamic properties of four iron oxides, namely, α-FeOOH, α-Fe 2 O 3 , Fe 3 O 4 , and FeO. Comparing our calculated results with available experimental data, we found that HSE (a = 0.15) (containing 15% "screened" Hartree-Fock exchange) can provide reliable values of lattice constants, Fe magnetic moments, band gaps, and formation energies of all four iron oxides, while standard HSE (a = 0.25) seriously overestimates the band gaps and formation energies. For PBE+U, a suitable U value can give quite good results for the electronic properties of each iron oxide, but it is challenging to accurately get other properties of the four iron oxides using the same U value. Subsequently, we calculated the Gibbs free energies of transformation reactions among iron oxides using the HSE (a = 0.15) functional and plotted the equilibrium phase diagrams of the iron oxide system under various conditions, which provide reliable theoretical insight into the phase transformations of iron oxides.

Polyphenolic extract from Hibiscus sabdariffa reduces body fat by inhibiting hepatic lipogenesis and preadipocyte adipogenesis.

PubMed

Kao, Erl-Shyh; Yang, Mon-Yuan; Hung, Chia-Hung; Huang, Chien-Ning; Wang, Chau-Jong

2016-01-01

Diets high in fat lead to excess lipid accumulation in adipose tissue, which is a crucial factor in the development of obesity, hepatitis, and hyperlipidemia. In this study, we investigated the anti-obesity effect of Hibiscus sabdariffa extract (HSE) in vivo. Hamsters fed a high-fat diet (HFD) develop symptoms of obesity, which were determined based on body weight changes and changes in plasma and serum triglycerides, free fatty acid concentrations, total cholesterol levels, LDL-C levels, HDL-C levels, and adipocyte tissue weight. HFD-fed hamsters were used to investigate the effects of HSE on symptoms of obesity such as adipogenesis and fatty liver, loss of blood glucose regulation, and serum ion imbalance. Interestingly, HSE treatment effectively reduced the effects of the HFD in hamsters in a dose-dependent manner. Further, after inducing maturation of preadipocytes, Hibiscus sabdariffa polyphenolic extract (HPE) was shown to suppress the adipogenesis of adipocytes. However, HPE does not affect the viability of preadipocytes. Therefore, both HSE and HPE are effective and viable treatment strategies for preventing the development and treating the symptoms of obesity.

Determinants of healthcare system's efficiency in OECD countries.

PubMed

Hadad, Sharon; Hadad, Yossi; Simon-Tuval, Tzahit

2013-04-01

Firstly, to compare healthcare systems' efficiency (HSE) using two models: one incorporating mostly inputs that are considered to be within the discretionary control of the healthcare system (i.e., physicians' density, inpatient bed density, and health expenditure), and another, including mostly inputs beyond healthcare systems' control (i.e., GDP, fruit and vegetables consumption, and health expenditure). Secondly, analyze whether institutional arrangements, population behavior, and socioeconomic or environmental determinants are associated with HSE. Data envelopment analysis (DEA) was utilized to calculate OECD countries' HSE. Life expectancy and infant survival rate were considered as outputs in both models. Healthcare systems' rankings according to the super-efficiency and the cross-efficiency ranking methods were used to analyze determinants associated with efficiency. (1) Healthcare systems in nine countries with large and stable economies were defined as efficient in model I, but were found to be inefficient in model II; (2) Gatekeeping and the presence of multiple insurers were associated with a lower efficiency; and (3) The association between socioeconomic and environmental indicators was found to be ambiguous. Countries striving to improve their HSE should aim to impact population behavior and welfare rather than only ensure adequate medical care. In addition, they may consider avoiding specific institutional arrangements, namely gatekeeping and the presence of multiple insurers. Finally, the ambiguous association found between socioeconomic and environmental indicators, and a country's HSE necessitates caution when interpreting different ranking techniques in a cross-country efficiency evaluation and needs further exploration.

Role of IL-6 and neopterin in the pathogenesis of herpetic encephalitis.

PubMed

Bociąga-Jasik, Monika; Cieśla, Andrzej; Kalinowska-Nowak, Anna; Skwara, Paweł; Garlicki, Aleksander; Mach, Tomasz

2011-01-01

Herpetic encephalitis (HSE) is one of the most severe infection of the central nervous system (CNS), connected with high mortality rate, even when appropriate therapy has been introduced. Better understanding of pathomechanisms responsible for neuronal injury during the course of the disease can be useful in the assessment of the risk of the occurrence of severe complications, as well as in potential introduction of additional therapeutic methods. The purpose of this study is to assess the correlation between concentration of neopterin and IL-6 in the CSF and serum, and the course of HSE. In this study, 36 patients with HSE were investigated, and the control group consisted of 32 patients in whom the infection of the CNS was excluded. We observed significantly higher concentration of neopterin and IL-6 in the CSF of patients with HSV as compared with the control group. Neopterin and IL-6 levels in the CSF correlated with the course of HSE. Higher values were connected with the risk of respiratory failure, development of permanent neurologic complications and patient death. Negative correlations between concentration of IL-6 and neopterin and patient condition assessed by Glasgow Coma Scale (GCS) were observed. Neopterin with high sensitivity and specificity allowed to predict the risk of death or severe neurological complications. Increased concentration of neopterin and IL-6 in the CSF and serum revealed reciprocal positive correlation. Assessment of the concentration of IL-6 and neopterin in the serum was not useful to predict the course of HSE.

The HSE indicator tool, psychological distress and work ability.

PubMed

Guidi, S; Bagnara, S; Fichera, G P

2012-04-01

The Health and Safety Executive (HSE) indicator tool is one of the most commonly used tools for assessing the risk of work-related stress. Few studies, however, have investigated whether and how its scales are related to psychological distress or other work-related health outcomes. To investigate the relationship between the HSE indicator tool, psychological distress, as measured by the General Health Questionnaire (GHQ)-12, and work ability, assessed by the Work Ability Index (WAI). All the employees of a mid-sized bank in Italy were asked to fill in an anonymous cross-sectional questionnaire. The questionnaire was structured in four sections: the first one comprised socio-demographic questions and the other three corresponded, respectively, to the Italian translations of the GHQ-12, the HSE and the WAI questionnaires. Four hundred and thirteen employees completed the questionnaire. The response rate was 99%. Controlling for age and gender, the indicator subscales were negatively associated with the adopted measures of psychological distress and work ability. The GHQ score was also highly correlated with the WAI score and able to explain ≈ 47% of its variance. The only subscale that was still significantly associated with the WAI after removing the effect of psychological distress was 'control'. The study presents new evidence for the validity of the HSE indicator tool to estimate the risk of work-related stress and suggests that most but not all the effects of psychosocial conditions on work ability might be mediated by the level of psychological distress induced by these conditions.

Alignment of defect levels and band edges through hybrid functionals: Effect of screening in the exchange term

NASA Astrophysics Data System (ADS)

Komsa, Hannu-Pekka; Broqvist, Peter; Pasquarello, Alfredo

2010-05-01

We investigate how various treatments of exact exchange affect defect charge transition levels and band edges in hybrid functional schemes for a variety of systems. We distinguish the effects of long-range vs short-range exchange and of local vs nonlocal exchange. This is achieved by the consideration of a set of four functionals, which comprise the semilocal Perdew-Burke-Ernzerhof (PBE) functional, the PBE hybrid (PBE0), the Heyd-Scuseria-Ernzerhof (HSE) functional, and a hybrid derived from PBE0 in which the Coulomb kernel in the exact exchange term is screened as in the HSE functional but which, unlike HSE, does not include a local expression compensating for the loss of the long-range exchange. We find that defect levels in PBE0 and in HSE almost coincide when aligned with respect to a common reference potential, due to the close total-energy differences in the two schemes. At variance, the HSE band edges determined within the same alignment scheme are found to shift significantly with respect to the PBE0 ones: the occupied and the unoccupied states undergo shifts of about +0.4eV and -0.4eV , respectively. These shifts are found to vary little among the materials considered. Through a rationale based on the behavior of local and nonlocal long-range exchange, this conclusion is generalized beyond the class of materials used in this study. Finally, we explicitly address the practice of tuning the band gap by adapting the fraction of exact exchange incorporated in the functional. When PBE0-like and HSE-like functionals are tuned to yield identical band gaps, their respective results for the positions of defect levels within the band gap and for the band alignments at interfaces are found to be very close.

Analysis of the intellectual structure of human space exploration research using a bibliometric approach: Focus on human related factors

NASA Astrophysics Data System (ADS)

Lee, Tai Sik; Lee, Yoon-Sun; Lee, Jaeho; Chang, Byung Chul

2018-02-01

Human space exploration (HSE) is an interdisciplinary field composed of a range of subjects that have developed dramatically over the last few decades. This paper investigates the intellectual structure of HSE research with a focus on human related factors. A bibliometric approach with quantitative analytical techniques is applied to study the development and growth of the research. This study retrieves 1921 papers on HSE related to human factors from the year 1990 to the year 2016 from Web of Science and constructs a critical citation network composed of 336 papers. Edge-betweenness-based clustering is used to classify the citation network into twelve distinct research clusters based on four research themes: "biological risks from space radiation," "health and performance during long-duration spaceflight," "program and in-situ resources for HSE missions," and "habitat and life support systems in the space environment." These research themes are also similar to the classification results of a co-occurrence analysis on keywords for a total of 1921 papers. Papers with high centrality scores are identified as important papers in terms of knowledge flow. Moreover, the intermediary role of papers in exchanging knowledge between HSE sub-areas is identified using brokerage analysis. The key-route main path highlights the theoretical development trajectories. Due to the recent dramatic increase in investment by international governments and the private sector, the theoretical development trajectories of key research themes have been expanding from furthering scientific and technical knowledge to include various social and economic issues, thus encouraging massive public participation. This study contributes to an understanding of research trends and popular issues in the field of HSE by introducing a powerful way of determining major research themes and development trajectories. This study will help researchers seek the underlying knowledge diffusion flow from multifaceted aspects to establish future research directions.

Adult Basic Education 1985-1986 End-of-Year Report.

ERIC Educational Resources Information Center

Mei, Dolores M.; And Others

The Adult Basic Education/High School Equivalency (ABE/HSE) Services Program provides basic educational services for out-of-school youth and adults in New York City. The program offers classes in basic literacy (BL), basic education (BE), high school equivalency (HSE), and English as a second language (ESL). The program's budget is $11 million.…

Thesis - keeping the management system {open_quotes}live{close_quotes} and reaching the workforce

DOE Office of Scientific and Technical Information (OSTI.GOV)

Primrose, M.J.; Bentley, P.D.; Graaf, G.C. van der

1996-12-31

Previous papers given to SPE conferences have described the Shell Group approach to Safety Management Systems and to Safety Cases. Their extension to HSE MS and to HSE Cases has also been addressed. Since 1984 the Enhanced Safety Management (ESM) programme within Shell companies has led to a significant improvement in the management of safety but it was only when structured management systems (based upon an understanding of the business processes) were introduced that true integration of HSE as a line responsibility became a reality. This paper describes the THESIS software package and the way that management systems have beenmore » made {open_quote}live{close_quote} and how workforce involvement can be demonstrated.« less

A gene-specific non-enhancer sequence is critical for expression from the promoter of the small heat shock protein gene αB-crystallin

PubMed Central

2014-01-01

Background Deciphering of the information content of eukaryotic promoters has remained confined to universal landmarks and conserved sequence elements such as enhancers and transcription factor binding motifs, which are considered sufficient for gene activation and regulation. Gene-specific sequences, interspersed between the canonical transacting factor binding sites or adjoining them within a promoter, are generally taken to be devoid of any regulatory information and have therefore been largely ignored. An unanswered question therefore is, do gene-specific sequences within a eukaryotic promoter have a role in gene activation? Here, we present an exhaustive experimental analysis of a gene-specific sequence adjoining the heat shock element (HSE) in the proximal promoter of the small heat shock protein gene, αB-crystallin (cryab). These sequences are highly conserved between the rodents and the humans. Results Using human retinal pigment epithelial cells in culture as the host, we have identified a 10-bp gene-specific promoter sequence (GPS), which, unlike an enhancer, controls expression from the promoter of this gene, only when in appropriate position and orientation. Notably, the data suggests that GPS in comparison with the HSE works in a context-independent fashion. Additionally, when moved upstream, about a nucleosome length of DNA (−154 bp) from the transcription start site (TSS), the activity of the promoter is markedly inhibited, suggesting its involvement in local promoter access. Importantly, we demonstrate that deletion of the GPS results in complete loss of cryab promoter activity in transgenic mice. Conclusions These data suggest that gene-specific sequences such as the GPS, identified here, may have critical roles in regulating gene-specific activity from eukaryotic promoters. PMID:24589182

Melt migration and mantle chromatography, 2: a time-series Os isotope study of Mauna Loa volcano, Hawaii

NASA Astrophysics Data System (ADS)

Hauri, Erik H.; Kurz, Mark D.

1997-12-01

We have determined the major element, trace element, and Os isotopic compositions of a stratigraphic suite of tholeiitic basalts spanning >30,000 years of the eruptive history of Mauna Loa volcano. Good correlations are observed between Os isotopes and the isotopes of Sr, Nd, Pb and He. In addition, the isotopes correlate with fractionation-corrected major element abundances within this single volcano, and provide a record of increased melting of mafic material with time at Mauna Loa. Chromatographic element fractionation during melt transport is shown to be negligible based on the good correlations of the isotopes of the compatible element Os with the other incompatible element tracers. The temporal variation at Mauna Loa is best described by the translation of the volcano over a Hawaiian plume which is radially zoned in composition. The radial zonation is a predicted consequence of thermal entrainment during flow in a mantle plume conduit.

Petrography and Geochemistry of Metals in Almahata Sitta Ureilites

NASA Technical Reports Server (NTRS)

Ross, A. J.; Herrin, J. S.; Mittlefehldt, D. W.; Downes, H.; Smith, C. L.; Lee, M. R.; Jones, A. P.; Jenniskens, P.; Shaddad, M. H,

2011-01-01

Ureilites are ultramafic achondrites, predominantly composed of olivine and pyroxenes with accessory carbon, metal and sulfide. The majority of ureilites are believed to represent the mantle of the ureilite parent body (UPB) [1]. Although ureilites have lost much of their original metal [2], the metal that remains retains a record of the formative processes. Almahata Sitta is predominantly composed of unbrecciated ureilites with a wide range of silicate compositions [3,4]. As a fall it presents a rare opportunity to examine fresh ureilite metal in-situ, and analyzing their highly siderophile element (HSE) ratios gives clues to their formation. Bulk siderophile element analyses of Almahata Sitta fall within the range observed in other ureilites [5]. We have examined the metals in seven ureilitic samples of Almahata Sitta (AS) and one associated chondrite fragment (AS#25).

CPSP/HSE Postgraduate Overseas Rotational Programme: Residents' Perspective.

PubMed

Gondal, Khalid Masood; Iqbal, Uzma; Arif, Seema; Ahmed, Arslan; Khan, Umair Ahmed

2016-04-01

To get direct upward feedback from the residents of first batch of CPSP/HSE Postgraduate Scholarship Programme. Mixed methods qualitative research study. CPSP, Regional Office, Lahore, in June 2015. It is a mixed-method study that was conducted in June, 2015. Data was collected through an email survey with 33 medical residents doing their rotation in Ireland; and focus group discussions were carried out with 8 residents, who had successfully completed their rotation. Data were collected through pre-designed questionnaires comprising of open- and close-ended questions. The data were entered into SPSS version 21 and analyzed. The mean age of residents was 29.9 &plusmn;1.1 years, 7 (21.2%) were females and 24 (72.7%) respondents were males. Residents agreed that HSE programme has improved their evidence-based decision making (mean score of 3.3 &plusmn;1.2) and enhanced professionalism (mean score of 3.6 &plusmn;1.1). They disagreed that training has polished their procedural skills (mean score 2.4 &plusmn;1.2). The identified strengths of the programme are: adopting a systematic approach towards patients, evidence-based decision making, better exposure and opportunities, financial stability and development of communication skills. The weaknesses are: less exposure to procedural skills, difficulty in synopsis and dissertation writing and difficulty in adjustment with rotational schedules. Residents of CPSP/HSE Programme believed that CPSP/HSE has improved their professionalism, communication skills and increased their future opportunities for career growth. Better communication between CPSP focal person and residents will help sort out many minor but important issues.

Isolation and analysis of a multifunctional triterpene synthase KcMS promoter region from mangrove plant kandelia candel

NASA Astrophysics Data System (ADS)

Basyuni, M.; Wati, R.; Sulistiyono, N.; Sumardi; Oku, H.; Baba, S.; Sagami, H.

2018-03-01

Molecular cloning of Kandelia candel KcMS gene has previously been cloned and encoded a multifunctional triterpene synthase. In this study, the KcMS gene promoter was cloned through Genome walking, sequenced, and analyzed. A 1,358 bp genomic DNA fragment of KcMS promoter was obtained. PLACE and PlantCARE analysis of the KcMS promoter revealed that there was some regulatory elements in response to environmental signals and involved in the regulation of gene expression. Results showed that four kinds of elements are regulated by hormone binding, namely 2 MeJA-responsiveness elements (CGTCA-motif and TGACG-motif), the ABRE (TACGTG) involved in abscisic acid responsiveness, gibberellin-related GARE-motif (AAACAGA), and the TGA-element (AACGAC) as an auxin-responsive element. Several elements in the KcMS have been shown in other plants to be responsive to abiotic stress. These motifs were MBS (CAACTG), TC-rich repeats, and eight light responsive elements. The KcMS promoter was also involved in the activation of defense genes in plants such as HSE (AAAAAATTC) and four circadian control elements (CAANNNNATC). The presence of multipotential regulatory motifs suggested that KcMS may be involved in regulation of plant tolerance to several types of stresses.

Progress Report, October, 1967, through April, 1968: Educational Component of the Public Service Careers Program.

ERIC Educational Resources Information Center

City Univ. of New York, NY. Office of Community Coll. Affairs.

Parallel with on-the-job training, this program provides remedial courses in High School Equivalency (HSE), Human Relations (HR), English as a Second Language (ESL) to help qualify candidates for public service careers in the Department of Hospitals and Department of Social Services, and Board of Education. HSE develops language, math, and reading…

Ecological policy in oil-gas complexes, HSE MS implementation in oil and gas company

NASA Astrophysics Data System (ADS)

Kochetkova, O. P.; Glyzina, T. S.; Vazim, A. A.; Tugutova, S. S.

2016-09-01

The paper considers the following issues: HSE MS international standard implementation in oil and gas industry, taking into account international practices; implementation of standards in oil and gas companies; policy in the field of environmental protection and occupational health and safety; achievement of planned indicators and targets in environmental protection and occupational health and safety.

Enhancing self-efficacy improves episodic future thinking and social-decision making in combat veterans with posttraumatic stress disorder.

PubMed

Brown, Adam D; Kouri, Nicole A; Rahman, Nadia; Joscelyne, Amy; Bryant, Richard A; Marmar, Charles R

2016-08-30

Posttraumatic Stress Disorder (PTSD) is associated with maladaptive changes in self-identity, including impoverished perceived self-efficacy. This study examined if enhancing perceptions of self-efficacy in combat veterans with and without symptoms of PTSD promotes cognitive strategies associated with positive mental health outcomes. Prior to completing a future thinking and social problem-solving task, sixty-two OEF/OIF veterans with and without symptoms of PTSD were randomized to either a high self-efficacy (HSE) induction in which they were asked to recall three autobiographical memories demonstrating self-efficacy or a control condition in which they recalled any three autobiographical events. An interaction between HSE and PTSD revealed that individuals with symptoms of PTSD in the HSE condition generated future events with more self-efficacious statements than those with PTSD in the control condition, whereas those without PTSD did not differ in self-efficacy content across the conditions. In addition, individuals in the HSE condition exhibited better social problem solving than those in the control condition. Increasing perceptions of self-efficacy may promote future thinking and problem solving in ways that are relevant to overcoming trauma and adversity. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

RSK2 represses HSF1 activation during heat shock

PubMed Central

Wang, Xiaozhe; Asea, Alexzander; Xie, Yue; Kabingu, Edith; Stevenson, Mary Ann; Calderwood, Stuart K.

2000-01-01

Heat shock transcription factor 1(HSF1) activation is a multistep process. The conversion of a latent cytoplasmic form to a nuclear, DNA binding state appears to be activated by nonsteroidal anti-inflammatory drugs. In previous studies, we showed that HSF 1 is phosphorylated by the protein kinase RSK2 in vitro and that this effect is inhibited by nonsteroidal anti-inflammatory drugs at the concentration that leads to the activation of HSF1 in vivo (Stevenson et al 1999). In the present study, using cells from a patient with Coffin-Lowry syndrome (deficient in RSK2), we demonstrate that RSK2 slightly represses activation of HSF1 in vivo at 37°C. In Coffin-Lowry syndrome cells, HSF1-HSE DNA binding activity after treatment with sodium salicylate was slightly higher than that in untreated cells, indicating that although RSK2 is involved in HSF1 regulation, it is not the unique protein kinase that suppresses HSF1-HSE binding activity at 37°C. However, heat shock treatment resulted in significantly higher HSF1-HSE binding activity in Coffin-Lowry syndrome cells as compared with normal controls, suggesting that RSK2 represses HSF1-HSE binding activity during heat shock. PMID:11189448

RSK2 represses HSF1 activation during heat shock.

PubMed

Wang, X; Asea, A; Xie, Y; Kabingu, E; Stevenson, M A; Calderwood, S K

2000-11-01

Heat shock transcription factor 1(HSF1) activation is a multistep process. The conversion of a latent cytoplasmic form to a nuclear, DNA binding state appears to be activated by nonsteroidal anti-inflammatory drugs. In previous studies, we showed that HSF 1 is phosphorylated by the protein kinase RSK2 in vitro and that this effect is inhibited by nonsteroidal anti-inflammatory drugs at the concentration that leads to the activation of HSF1 in vivo (Stevenson et al 1999). In the present study, using cells from a patient with Coffin-Lowry syndrome (deficient in RSK2), we demonstrate that RSK2 slightly represses activation of HSF1 in vivo at 37 degrees C. In Coffin-Lowry syndrome cells, HSF1-HSE DNA binding activity after treatment with sodium salicylate was slightly higher than that in untreated cells, indicating that although RSK2 is involved in HSF1 regulation, it is not the unique protein kinase that suppresses HSF1-HSE binding activity at 37 degrees C. However, heat shock treatment resulted in significantly higher HSF1-HSE binding activity in Coffin-Lowry syndrome cells as compared with normal controls, suggesting that RSK2 represses HSF1-HSE binding activity during heat shock.

Diurnal effects of prior heat stress exposure on sprint and endurance exercise capacity in the heat.

PubMed

Otani, Hidenori; Kaya, Mitsuharu; Tamaki, Akira; Goto, Heita; Goto, Takayuki; Shirato, Minayuki

2018-03-21

Active individuals often perform exercises in the heat following heat stress exposure (HSE) regardless of the time-of-day and its variation in body temperature. However, there is no information concerning the diurnal effects of a rise in body temperature after HSE on subsequent exercise performance in a hot environnment. This study therefore investigated the diurnal effects of prior HSE on both sprint and endurance exercise capacity in the heat. Eight male volunteers completed four trials which included sprint and endurance cycling tests at 30 °C and 50% relative humidity. At first, volunteers completed a 30-min pre-exercise routine (30-PR): a seated rest in a temperate environment in AM (AmR) or PM (PmR) (Rest trials); and a warm water immersion at 40 °C to induce a 1 °C increase in core temperature in AM (AmW) or PM (PmW) (HSE trials). Volunteers subsequently commenced exercise at 0800 h in AmR/AmW and at 1700 h in PmR/PmW. The sprint test determined a 10-sec maximal sprint power at 5 kp. Then, the endurance test was conducted to measure time to exhaustion at 60% peak oxygen uptake. Maximal sprint power was similar between trials (p = 0.787). Time to exhaustion in AmW (mean±SD; 15 ± 8 min) was less than AmR (38 ± 16 min; p < 0.01) and PmR (43 ± 24 min; p < 0.01) but similar with PmW (24 ± 9 min). Core temperature was higher from post 30-PR to 6 min into the endurance test in AmW and PmW than AmR and PmR (p < 0.05) and at post 30-PR and the start of the endurance test in PmR than AmR (p < 0.05). The rate of rise in core temperature during the endurance test was greater in AmR than AmW and PmW (p < 0.05). Mean skin temperature was higher from post 30-PR to 6 min into the endurance test in HSE trials than Rest trials (p < 0.05). Mean body temperature was higher from post 30-PR to 6 min into the endurance test in AmW and PmW than AmR and PmR (p < 0.05) and the start to 6 min into the endurance test in PmR than AmR (p < 0.05). Convective, radiant, dry and evaporative heat losses were greater on HSE trials than on Rest trials (p < 0.001). Heart rate and cutaneous vascular conductance were higher at post 30-PR in HSE trials than Rest trials (p < 0.05). Thermal sensation was higher from post 30-PR to the start of the endurance test in AmW and PmW than AmR and PmR (p < 0.05). Perceived exertion from the start to 6 min into the endurance test was higher in HSE trials than Rest trials (p < 0.05). This study demonstrates that an approximately 1 °C increase in core temperature by prior HSE has the diurnal effects on endurance exercise capacity but not on sprint exercise capacity in the heat. Moreover, prior HSE reduces endurance exercise capacity in AM, but not in PM. This reduction is associated with a large difference in pre-exercise core temperature between AM trials which is caused by a relatively lower body temperature in the morning due to the time-of-day variation and contributes to lengthening the attainment of high core temperature during exercise in AmR.

A process evaluation accompanying an attempted randomized controlled trial of an evidence service for health system policymakers.

PubMed

Wilson, Michael G; Grimshaw, Jeremy M; Haynes, R Brian; Hanna, Steven E; Raina, Parminder; Gruen, Russell; Ouimet, Mathieu; Lavis, John N

2015-12-12

We developed an evidence service that draws inputs from Health Systems Evidence (HSE), which is a comprehensive database of research evidence about governance, financial and delivery arrangements within health systems and about implementation strategies relevant to health systems. Our goal was to evaluate whether, how and why a 'full-serve' evidence service increases the use of synthesized research evidence by policy analysts and advisors in the Ontario Ministry of Health and Long-Term Care as compared to a 'self-serve' evidence service. We attempted to conduct a two-arm, 10-month randomized controlled trial (RCT), along with a follow-up qualitative process evaluation, but we terminated the RCT when we failed to reach our recruitment target. For the qualitative process evaluation we modified the original interview guide to allow us to explore the (1) factors influencing participation in the trial; (2) usage of HSE, factors explaining usage patterns, and strategies to increase usage; (3) participation in training workshops and use of other supports; and (4) views about and experiences with key HSE features. We terminated the RCT given our 15% recruitment rate. Six factors were identified by those who had agreed to participate in the trial as encouraging their participation: relevance of the study to participants' own work; familiarity with the researchers; personal view of the importance of using research evidence in policymaking; academic background; support from supervisors; and participation of colleagues. Most reported that they never, infrequently or inconsistently used HSE and suggested strategies to increase its use, including regular email reminders and employee training. However, only two participants indicated that employee training, in the form of a workshop about finding and using research evidence, had influenced their use of HSE. Most participants found HSE features to be intuitive and helpful, although registration/sign-in and some page formats (particularly the advanced search page and detailed search results page) discouraged their use or did not optimize the user experience. The qualitative findings informed a re-design of HSE, which allows users to more efficiently find and use research evidence about how to strengthen or reform health systems or in how to get cost-effective programs, services and drugs to those who need them. Our experience with RCT recruitment suggests the need to consider changing the unit of allocation to divisions instead of individuals within divisions, among other lessons. This protocol for this study is published in Implementation Science and registered with ClinicalTrials.gov ( HHS/FHS REB 10-267 ).

Al Basrah Oil Terminal. Basrah, Iraq

DTIC Science & Technology

2007-04-26

made of plastic Conclusion Emergency evacuation capabilities are very important for the protection of personnel working on ABOT. The work... EEA ) Program and Health, Safety, and Environmental (HSE) Program URIs 22671 and 22672 As mentioned earlier in the Lifeboat section of this...accounting of all personnel.” PIJV recommended the development of an EEA plan and HSE program manual for the ABOT personnel. The EEA plan was

Hydrothermal syntheses, structures, and properties of the new uranyl selenites Ag(2)(UO(2))(SeO(3))(2), M[(UO(2))(HSeO(3))(SeO(3))] (M = K, Rb, Cs, Tl), and Pb(UO(2))(SeO(3))(2).

PubMed

Almond, Philip M; Albrecht-Schmitt, Thomas E

2002-03-11

The transition metal, alkali metal, and main group uranyl selenites, Ag(2)(UO(2))(SeO(3))(2) (1), K[(UO(2))(HSeO(3))(SeO(3))] (2), Rb[(UO(2))(HSeO(3))(SeO(3))] (3), Cs[(UO(2))(HSeO(3))(SeO(3))] (4), Tl[(UO(2))(HSeO(3))(SeO(3))] (5), and Pb(UO(2))(SeO(3))(2) (6), have been prepared from the hydrothermal reactions of AgNO(3), KCl, RbCl, CsCl, TlCl, or Pb(NO(3))(2) with UO(3) and SeO(2) at 180 degrees C for 3 d. The structures of 1-5 contain similar [(UO(2))(SeO(3))(2)](2-) sheets constructed from pentagonal bipyramidal UO(7) units that are joined by bridging SeO(3)(2-) anions. In 1, the selenite oxo ligands that are not utilized within the layers coordinate the Ag(+) cations to create a three-dimensional network structure. In 2-5, half of the selenite ligands are monoprotonated to yield a layer composition of [(UO(2))(HSeO(3))(SeO(3))](1-), and coordination of the K(+), Rb(+), Cs(+), and Tl(+) cations occurs through long ionic contacts. The structure of 6 contains a uranyl selenite layered substructure that differs substantially from those in 1-5 because the selenite anions adopt both bridging and chelating binding modes to the uranyl centers. Furthermore, the Pb(2+) cations form strong covalent bonds with these anions creating a three-dimensional framework. These cations occur as distorted square pyramidal PbO(5) units with stereochemically active lone pairs of electrons. These polyhedra align along the c-axis to create a polar structure. Second-harmonic generation (SHG) measurements revealed a response of 5x alpha-quartz for 6. The diffuse reflectance spectrum of 6 shows optical transitions at 330 and 440 nm. The trailing off of the 440 nm transition to longer wavelengths is responsible for the orange coloration of 6.

Peridotite xenoliths from the Polynesian Austral and Samoa hotspots: Implications for the destruction of ancient 187Os and 142Nd isotopic domains and the preservation of Hadean 129Xe in the modern convecting mantle

NASA Astrophysics Data System (ADS)

Jackson, M. G.; Shirey, S. B.; Hauri, E. H.; Kurz, M. D.; Rizo, H.

2016-07-01

The Re-Os systematics in 13 peridotite xenoliths hosted in young (<0.39 myr) rejuvenated lavas from the Samoan island of Savai'i and 8 peridotite xenoliths from 6 to 10 myr old lavas from the Austral island of Tubuai have been examined to evaluate the history of the oceanic mantle in this region. Modal mineralogy, trace element compositions and 187Os/188Os ratios suggest that these peridotites are not cognate or residual to mantle plumes but rather samples of Pacific oceanic lithosphere created at the ridge. Savai'i and Tubuai islands lie along a flow line in the Pacific plate, and provide two snapshots (separated by over 40 Ma in time) of Pacific mantle that originated in the same region of the East Pacific rise. Tubuai xenoliths exhibit 187Os/188Os from 0.1163 to 0.1304, and Savai'i (Samoa) xenoliths span a smaller range from 0.1173 to 0.1284. The 187Os/188Os ratios measured in Tubuai xenoliths are lower than (and show no overlap with) basalts from Tubuai. The 187Os/188Os of the Savai'i xenoliths overlap the isotopic compositions of lavas from the island of Savai'i, but also extend to lower 187Os/188Os than the lavas. 3He/4He measurements of a subset of the xenoliths range from 2.5 to 6.4 Ra for Tubuai and 10.8 to 12.4 Ra for Savai'i. Like abyssal peridotites and xenoliths from oceanic hotspots that sample the convecting mantle, Os isotopes from the Savai'i and Tubuai xenolith suites are relatively unradiogenic, but do not preserve a record of depleted early-formed (Hadean and Archean) mantle domains expected from earlier cycles of ridge-related depletion, continent extraction, or subcontinental lithospheric mantle erosion. The lack of preservation of early-formed, geochemically-depleted Os-isotopic and 142Nd/144Nd domains in the modern convecting mantle contrasts with the preservation of early-formed (early-Hadean) 129Xe/130Xe isotopic heterogeneities in the convecting mantle. This can be explained if the initial isotopic signatures in Re-Os and Sm-Nd systems are erased by recycling because the parent and daughter elements are retained in subducting slabs and more efficiently returned to the mantle during subduction than Xe. In this way, early-formed Os and Nd-isotopic heterogeneities could have been overprinted with, and diluted by, younger isotopic signatures. In contrast, preservation of early-formed heterogeneities in the modern convecting mantle is possible for other elements, such as Xe, that are not as efficiently recycled back into the mantle, owing to greater fluid mobility that concentrates such elements in the near-surface. Differing recycling efficiencies for Os, Nd and Xe lead to wide differences in the preservation of Hadean isotopic signatures of these elements in the modern convecting mantle. In general, incompatible elements that are fluid mobile (e.g., Xe) concentrate in surface reservoirs and are more likely to preserve Hadean geochemical signatures in the convecting mantle than compatible elements (e.g., Os) and fluid immobile incompatible elements (e.g., Nd).

Herpes Simplex Encephalitis: Lack of Clinical Benefit of Long-term Valacyclovir Therapy.

PubMed

Gnann, John W; Sköldenberg, Birgit; Hart, John; Aurelius, Elisabeth; Schliamser, Silvia; Studahl, Marie; Eriksson, Britt-Marie; Hanley, Daniel; Aoki, Fred; Jackson, Alan C; Griffiths, Paul; Miedzinski, Lil; Hanfelt-Goade, Diane; Hinthorn, Daniel; Ahlm, Clas; Aksamit, Allen; Cruz-Flores, Salvador; Dale, Ilet; Cloud, Gretchen; Jester, Penelope; Whitley, Richard J

2015-09-01

Despite the proven efficacy of acyclovir (ACV) therapy, herpes simplex encephalitis (HSE) continues to cause substantial morbidity and mortality. Among patients with HSE treated with ACV, the mortality rate is approximately 14%-19%. Among survivors, 45%-60% have neuropsychological sequelae at 1 year. Thus, improving therapeutic approaches to HSE remains a high priority. Following completion of a standard course of intravenous ACV, 87 adult patients with HSE (confirmed by positive polymerase chain reaction [PCR] for herpes simplex virus DNA in cerebrospinal fluid) were randomized to receive either valacyclovir (VACV) 2 g thrice daily (n = 40) or placebo tablets (n = 47) for 90 days (12 tablets of study medication daily). The primary endpoint was survival with no or mild neuropsychological impairment at 12 months, as measured by the Mattis Dementia Rating Scale (MDRS). Logistic regression was utilized to assess factors related to the primary endpoint. The demographic characteristics of the 2 randomization groups were statistically similar with no significant differences in age, sex, or race. At 12 months, there was no significant difference in the MDRS scoring for VACV-treated vs placebo recipients, with 85.7% and 90.2%, respectively, of patients demonstrating no or mild neuropsychological impairment (P = .72). No significant study-related adverse events were encountered in either treatment group. Following standard treatment with intravenous ACV for PCR-confirmed HSE, an additional 3-month course of oral VACV therapy did not provide added benefit as measured by neuropsychological testing 12 months later in a population of relatively high-functioning survivors. NCT00031486. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Autoimmune post-herpes simplex encephalitis of adults and teenagers.

PubMed

Armangue, Thaís; Moris, Germán; Cantarín-Extremera, Verónica; Conde, Carlos Enrique; Rostasy, Kevin; Erro, Maria Elena; Portilla-Cuenca, Juan Carlos; Turón-Viñas, Eulàlia; Málaga, Ignacio; Muñoz-Cabello, Beatriz; Torres-Torres, Carmen; Llufriu, Sara; González-Gutiérrez-Solana, Luis; González, Guillermo; Casado-Naranjo, Ignacio; Rosenfeld, Myrna; Graus, Francesc; Dalmau, Josep

2015-11-17

To report 14 patients with immune-mediated relapsing symptoms post-herpes simplex encephalitis (HSE) and to compare the clinical and immunologic features of the teenage and adult group with those of young children. Prospective observational study of patients diagnosed between June 2013 and February 2015. Immunologic techniques have been reported previously. Among the teenage and adult group (8 patients, median age 40 years, range 13-69; 5 male), 3 had an acute symptom presentation suggesting a viral relapse, and 5 a presentation contiguous with HSE suggesting a recrudescence of previous deficits. Seven patients developed severe psychiatric/behavioral symptoms disrupting all social interactions, and one refractory status epilepticus. Blepharospasm occurred in one patient. Five patients had CSF antibodies against NMDA receptor (NMDAR) and 3 against unknown neuronal cell surface proteins. In 5/6 patients, the brain MRI showed new areas of contrast enhancement that decreased after immunotherapy and clinical improvement. Immunotherapy was useful in 7/7 patients, sometimes with impressive recoveries, returning to their baseline HSE residual deficits. Compared with the 6 younger children (median age 13 months, range 6-20, all with NMDAR antibodies), the teenagers and adults were less likely to develop choreoathetosis (0/8 vs 6/6, p < 0.01) and decreased level of consciousness (2/8 vs 6/6, p < 0.01) and had longer delays in diagnosis and treatment (interval relapse/antibody testing 85 days, range 17-296, vs 4 days, range 0-33, p = 0.037). In teenagers and adults, the immune-mediated relapsing syndrome post-HSE is different from that known in young children as choreoathetosis post-HSE and is underrecognized. Prompt diagnosis is important because immunotherapy can be highly effective. © 2015 American Academy of Neurology.

Social class-related gradient in the association of skeletal growth with blood pressure among adolescent boys in India.

PubMed

Rao, Shobha; Apte, Priti

2009-12-01

In view of the fact that height differences between socio-economic groups are apparent early in childhood, it is of interest to examine whether skeletal growth is reflective of the social class gradient in CVD risk. The present study examined blood pressure levels, adiposity and growth of adolescent boys from high and low social classes. In a cross-sectional study, skeletal growth (height and sitting height), adiposity (weight, BMI and body fat) and blood pressure levels of the adolescents were measured. Pune, India. Adolescent schoolboys (9-16 years) from high socio-economic (HSE; n 1146) and low socio-economic (LSE; n 932) class. LSE boys were thin, short and undernourished (mean BMI: 15.5 kg/m2 v. 19.3 kg/m2 in HSE boys, P = 0.00). Social gradient was revealed in differing health risks. The prevalence of high systolic blood pressure (HSBP) was high in HSE class (10.5 % v. 2.7 % in LSE class, P = 0.00) and was associated with adiposity, while the prevalence of high diastolic blood pressure (HDBP) was high in LSE class (9.8 % v. 7.0 % in HSE class, P = 0.00) and had only a weak association with adiposity. Despite this, lower ratio of leg length to height was associated with significantly higher respective health risks, i.e. for HDBP in LSE class (OR = 1.99, 95 % CI 1.14, 3.47) and for HSBP in HSE class (OR = 1.69, 95 % CI 1.02, 2.77). As stunting in childhood is a major problem in India and Asia, the leg length to height indicator needs to be validated in different populations to understand CVD risks.

[Monitoring early toxicity of heavy metals including Hg using a HSE-SEAP reporter gene].

PubMed

Yu, Zhan-Jiang; Yang, Qin; Yang, Xiao-Da; Wang, Kui

2006-08-01

To develop a cellular assay based on heat shock signal pathway and secreted alkaline phosphatase (SEAP) reporter gene for investigating/predicting the early toxicity of heavy metals on HeLa cells in Chinese traditional medicine (TCM). The pHSE-SEAP plasmid was transfected into HeLa cells to build a HSE-SEAP-HeLa cell model. For validation of the model, the transfected cells were treated by either heating at 42 degrees C for 1 h or incubated with 5 mol x L(-1) CdCl2 for 4 h. Then the cells were covered in complete DMEM culture medium for 48 h and the activity of SEAP (reflecting the cellular level of heat shock protein) in cultural supernatants was measured; meanwhile, cell viability was determined by MTT assays. In addition, the cells were treated by four mercury compounds, HgCl2, merthilate sodium, HgS and cinnabar at the sub-lethal concentrations (determined by MTT assays). Then the heat shock response was detected likewise. Significant level of secreted alkaline phosphatase (SEAP) was found in pHSE-SEAP transfected HeLa cells treated either by heating (42 degrees C) or incubating with CdCl2. The heat shock protein was induced by CdCl2 before decrease of cell viability was observed. All four mercury compounds induced heat shock response in both time and concentration-dependant manner. However, there were big differences among the mercury compounds, suggesting potential differences for early-stage toxicity in vivo. The pHSE-SEAP transfected HeLa cells respond effectively to heat shock and metal stresses, and therefore provide a practical and repeatable assay for investigating/predicting the early toxicity of heavy metals and mineral-containing drugs in TCM.

SNIP1: a new activator of HSE signaling pathway.

PubMed

Li, Qiang; An, Jian; Liu, Xianghua; Zhang, Mingjun; Ling, Yichen; Wang, Chenji; Zhao, Jing; Yu, Long

2012-03-01

In the last 10 years, more and more attention has been focused on SNIP1 (Smad nuclear interacting protein 1), which functions as a transcriptional coactivator. We report here that through quantitative real-time PCR analysis in 18 different human tissues, SNIP1 was found to be expressed ubiquitously. When overexpressed in HeLa cells, SNIP1-EGFP fused protein exhibited a nuclear localization with a characteristic subnuclear distribution in speckles or formed larger discrete nuclear bodies in some cells. Reporter gene assay showed that overexpression of SNIP1 in HEK 293 cells or H1299 cells strongly activated the HSE signaling pathway. Moreover, SNIP1 could selectively regulate the transcription of HSP70A1A and HSP27. Taken together, our findings suggest that SNIP1 might also be a positive regulator of HSE signaling pathway.

Staff support for the Health Service Executive (HSE) global health programme.

PubMed

Fitzpatrick, G; Weakliam, D; Boland, M; Fitzgerald, M

2014-03-01

The Global Health programme (GHP) within the Health Service Executive (HSE) aims to improve health in developing countries by creating partnerships between Irish and developing world healthcare institutions. To ascertain the level of interest among HSE staff for the GHP a web-based survey was conducted. 1,028 responses were received. Medical professionals, 202 (27.7%) composed the largest category of respondents. The majority, 503 (69.3%) of respondents wished to actively participate in the GHP. 237 (23.1%) staff had previous experience of working in the developing world. This survey highlighted a number of themes respondents considered important for successful partnerships including: reciprocal staff exchange, joint scientific research, the avoidance of "brain drain" and utilising the Internet to link institutions. Less than 1% (2/203) of comments expressed a negative view of the GHP.

Oxidation of aqueous polyselenide solutions. A mechanistic pulse radiolysis study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldbach, A.; Saboungi, M.L.; Johnson, J.A.

2000-05-04

The oxidation of aqueous polyselenide solutions was studied by pulse radiolysis in the presence of N{sub 2}O at pH 12.3; the hydroxyl radical OH was the predominant oxidant, while hydrogen selenide anions HSe{sup {minus}} and triselenide dianions Se{sub 3}{sup 2{minus}} were the major selenide species in the starting solution. The progress of the oxidation was monitored by optical spectroscopy. Transient polyselenides appeared immediately after the electron pulse and rapidly proceeded to form adducts with HSe{sup {minus}}, i.e., HSe{sub 2}{sup 2{minus}} and H{sub 2}Se{sub 2}{sup {minus}}, and a fairly long-lived intermediate that was identified as the diselenide radical anion Se{sub 2}{supmore » {minus}}. These radicals recombine to give eventually the tetraselenide dianion, Se{sub 4}{sup 2{minus}}.« less

Osmium mass balance in peridotite and the effects of mantle-derived sulphides on basalt petrogenesis

NASA Astrophysics Data System (ADS)

Harvey, J.; Dale, C. W.; Gannoun, A.; Burton, K. W.

2011-10-01

Analyses of enriched mantle (EM)-basalts, using lithophile element-based isotope systems, have long provided evidence for discrete mantle reservoirs with variable composition. Upon partial melting, the mantle reservoir imparts its isotopic fingerprint upon the partial melt produced. However, it has increasingly been recognised that it may not be simple to delimit these previously well-defined mantle reservoirs; the "mantle zoo" may contain more reservoirs than previously envisaged. Here we demonstrate that a simple model with varying contributions from two populations of compositionally distinct mantle sulphides can readily account for the observed heterogeneities in Os isotope systematics of such basalts without additional mantle reservoirs. Osmium elemental and isotopic analyses of individual sulphide grains separated from spinel lherzolites from Kilbourne Hole, New Mexico, USA demonstrate that two discrete populations of mantle sulphide exist in terms of both Re-Os systematics and textural relationship with co-existing silicates. One population, with a rounded morphology, is preserved in silicate grains and typically possesses high [Os] and low [Re] with unradiogenic, typically sub-chondritic 187Os/ 188Os attributable to long term isolation in a low-Re environment. By contrast, irregular-shaped sulphides, preserved along silicate grain boundaries, possess low [Os], higher [Re] and a wider range of, but generally supra-chondritic 187Os/ 188Os ([Os] typically ⩽ 1-2 ppm, 187Os/ 188Os ⩽ 0.3729; this study). This population is thought to represent metasomatic sulphide. Uncontaminated silicate phases contain negligible Os (<100 ppt) therefore the Os elemental and isotope composition of basalts is dominated by volumetrically insignificant sulphide ([Os] ⩽ 37 ppm; this study). During the early stages of partial melting, supra-chondritic interstitial sulphides are mobilised and incorporated into the melt, adding their radiogenic 187Os/ 188Os signature. Only when sulphides armoured within silicates are exposed to the melt through continued partial melting will enclosed sulphides add their high [Os] and unradiogenic 187Os/ 188Os to the aggregate melt. Platinum-group element data for whole rocks are also consistent with this scenario. The sequence of (i) addition of all of the metasomatic sulphide, followed by (ii) the incorporation of small amounts of armoured sulphide can thus account for the range of both [Os] and 187Os/ 188Os of EM-basalts worldwide without the need for contributions from additional silicate mantle reservoirs.

Cardiac and Vascular Synergic Protective Effect of Olea europea L. Leaves and Hibiscus sabdariffa L. Flower Extracts.

PubMed

Micucci, Matteo; Malaguti, Marco; Toschi, Tullia Gallina; Di Lecce, Giuseppe; Aldini, Rita; Angeletti, Andrea; Chiarini, Alberto; Budriesi, Roberta; Hrelia, Silvana

2015-01-01

This study was aimed at investigating the cardiovascular effects of an Olea europea L. leaf extract (OEE), of a Hibiscus sabdariffa L. flower extract (HSE), and of their 13 : 2 w/w mixture in order to assess their cardiac and vascular activity. Both extracts were fully characterized in their bioactive compounds by HPLC-MS/MS analysis. The study was performed using primary vascular endothelial cells (HUVECs) to investigate the antioxidant and cytoprotective effect of the extracts and their mixture and isolated guinea-pig left and right atria and aorta to evaluate the inotropic and chronotropic activities and vasorelaxant properties. In cultured HUVECs, OEE and HSE reduced intracellular reactive oxygen species formation and improved cell viability, following oxidative stress in dose-dependent manner. OEE and HSE exerted negative inotropic and vasorelaxant effects without any chronotropic property. Interestingly, the mixture exerted higher cytoprotective effects and antioxidant activities. Moreover, the mixture exerted an inotropic effect similar to each single extract, while it revealed an intrinsic negative chronotropic activity different from the single extract; its relaxant activity was higher than that of each single extract. In conclusion OEE and HSE mixture has a good potential for pharmaceutical and nutraceutical application, thanks to the synergistic effects of the single phytochemicals.

Functional IRF3 deficiency in a patient with herpes simplex encephalitis.

PubMed

Andersen, Line Lykke; Mørk, Nanna; Reinert, Line S; Kofod-Olsen, Emil; Narita, Ryo; Jørgensen, Sofie E; Skipper, Kristian A; Höning, Klara; Gad, Hans Henrik; Østergaard, Lars; Ørntoft, Torben F; Hornung, Veit; Paludan, Søren R; Mikkelsen, Jacob Giehm; Fujita, Takashi; Christiansen, Mette; Hartmann, Rune; Mogensen, Trine H

2015-08-24

Herpes simplex encephalitis (HSE) in children has previously been linked to defects in type I interferon (IFN) production downstream of Toll-like receptor 3. Here, we describe a novel genetic etiology of HSE by identifying a heterozygous loss-of-function mutation in the IFN regulatory factor 3 (IRF3) gene, leading to autosomal dominant (AD) IRF3 deficiency by haploinsufficiency, in an adolescent female patient with HSE. IRF3 is activated by most pattern recognition receptors recognizing viral infections and plays an essential role in induction of type I IFN. The identified IRF3 R285Q amino acid substitution results in impaired IFN responses to HSV-1 infection and particularly impairs signaling through the TLR3-TRIF pathway. In addition, the R285Q mutant of IRF3 fails to become phosphorylated at S386 and undergo dimerization, and thus has impaired ability to activate transcription. Finally, transduction with WT IRF3 rescues the ability of patient fibroblasts to express IFN in response to HSV-1 infection. The identification of IRF3 deficiency in HSE provides the first description of a defect in an IFN-regulating transcription factor conferring increased susceptibility to a viral infection in the CNS in humans. © 2015 Andersen et al.

Potential risk of developing herpes simplex encephalitis in patients treated with sildenafil following primary exposure to genital herpes.

PubMed

Goren, A; Mccoy, J; Kovacevic, M; Situm, M; Lonky, N

2017-01-01

Herpes simplex encephalitis (HSE) is associated with significant mortality and morbidity. As a consequence of HSE, up to 75% of infected individuals die or experience irreversible neurological damage. While the pathogenesis of the disease is unknown, it is traditionally hypothesized that the viral infection occurs by neuronal transmission directly from peripheral sites. Non-neuronal modes of infection have generally been overlooked as the brain is protected by the blood-brain-barrier (BBB). The BBB poses an effective barrier to pathogens as well as to drugs such as chemotherapies. In the pursuit to deliver chemotherapeutic agents to the brain, several studies demonstrated that phosphodiesterase type 5 (PDE5) inhibitors, such as sildenafil, may increase the permeability of the BBB enabling successful delivery of chemotherapeutic agents to the brain. In this communication, we report a case of HSE infection in a 62-year-old man, which we suspect was facilitated by the use of sildenafil during a primary genital herpes simple virus (HSV) infection. Due to large number of patients treated with PDE5 inhibitors for erectile dysfunction and the high incidence of genital HSV infection in the general population, a larger study should examine the potential risk of developing HSE in patients treated with PDE5 inhibitors.

Methods of defining hypertension in electronic medical records: validation against national survey data

PubMed Central

Peng, Mingkai; Chen, Guanmin; Kaplan, Gilaad G.; Lix, Lisa M.; Drummond, Neil; Lucyk, Kelsey; Garies, Stephanie; Lowerison, Mark; Weibe, Samuel; Quan, Hude

2016-01-01

Background Electronic medical records (EMR) can be a cost-effective source for hypertension surveillance. However, diagnosis of hypertension in EMR is commonly under-coded and warrants the needs to review blood pressure and antihypertensive drugs for hypertension case identification. Methods We included all the patients actively registered in The Health Improvement Network (THIN) database, UK, on 31 December 2011. Three case definitions using diagnosis code, antihypertensive drug prescriptions and abnormal blood pressure, respectively, were used to identify hypertension patients. We compared the prevalence and treatment rate of hypertension in THIN with results from Health Survey for England (HSE) in 2011. Results Compared with prevalence reported by HSE (29.7%), the use of diagnosis code alone (14.0%) underestimated hypertension prevalence. The use of any of the definitions (38.4%) or combination of antihypertensive drug prescriptions and abnormal blood pressure (38.4%) had higher prevalence than HSE. The use of diagnosis code or two abnormal blood pressure records with a 2-year period (31.1%) had similar prevalence and treatment rate of hypertension with HSE. Conclusions Different definitions should be used for different study purposes. The definition of ‘diagnosis code or two abnormal blood pressure records with a 2-year period’ could be used for hypertension surveillance in THIN. PMID:26547088

North Cork HSE orthodontic treatment waiting list 2009-2010: retrospective audit of patient records.

PubMed

McSwiney, Timothy P; Millett, Declan T

2013-01-01

To evaluate the case profile and verify the treatment eligibility (based on the modified IOTN) from written case records, of patients accepted for orthodontic treatment from the North Cork area of HSE South. A data collection form was designed and applied to the written case records of 200 consecutive patients accepted for orthodontic treatment in 2009/2010. Data relating to the IOTN (DHC and AC, where relevant) were provided by a calibrated examiner. Based on the written case records, most (57%) of the treatment cohort were female and had an average age of 14 years and two months. The predominant malocclusion was Class II division 1 (40%). The prevalence of Class III malocclusion was high at 18%. A total of 61% of patients were in grade 5 and 36% in grade 4. The majority of patients in each of these grades fell into DHC 5a (32%), followed by 5i (24%) and 4d AC > 8 (16%). Written case records conclude that patients accepted for orthodontic treatment from the North Cork area of HSE South were predominantly female. Class II division 1 malocclusion was the most common accepted for treatment. These records verify that those patients accepted for orthodontic treatment satisfy the eligibility criteria for HSE treatment.

Implications of Recent Legislation and Strategy Developments in UK - Impact on regulation of radioactive waste management at nuclear installations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Griffiths, J.S.; Rutherford, J.; Boydon, F.M.D.

2007-07-01

Recently a number of factors are having a significant impact on the environment within which the UK nuclear industry operates. This presents a challenge for regulators and how they ensure delivery of proportionate regulation. The traditional organisations that made up the nuclear operators/ licensees that Health and Safety Executive (HSE) has regulated for over 30 years have changed radically with new company structures still being developed leading to the increased nuclear industry fragmentation. HSE already has some regulatory experience in this area but the pace of change is increasing as a result of competition for contracts to operate UK sitesmore » or facilities. This has already resulted in HSE undertaking a significant programme of work to regulate the re-licensing of such sites to new organisations. In response to this more dynamic environment we are examining our approach to regulation plus the safety assessment standards that need to be adopted within this changing environment. This paper will outline recent examples of how HSE has adapted its regulatory approach to specific case studies, along with discussion of how it intends to apply standards at a national and international level to illustrate the challenges that are faced in a changing operating environment. (authors)« less

Cardiac and Vascular Synergic Protective Effect of Olea europea L. Leaves and Hibiscus sabdariffa L. Flower Extracts

PubMed Central

Micucci, Matteo; Gallina Toschi, Tullia; Di Lecce, Giuseppe; Aldini, Rita; Angeletti, Andrea; Chiarini, Alberto

2015-01-01

This study was aimed at investigating the cardiovascular effects of an Olea europea L. leaf extract (OEE), of a Hibiscus sabdariffa L. flower extract (HSE), and of their 13 : 2 w/w mixture in order to assess their cardiac and vascular activity. Both extracts were fully characterized in their bioactive compounds by HPLC-MS/MS analysis. The study was performed using primary vascular endothelial cells (HUVECs) to investigate the antioxidant and cytoprotective effect of the extracts and their mixture and isolated guinea-pig left and right atria and aorta to evaluate the inotropic and chronotropic activities and vasorelaxant properties. In cultured HUVECs, OEE and HSE reduced intracellular reactive oxygen species formation and improved cell viability, following oxidative stress in dose-dependent manner. OEE and HSE exerted negative inotropic and vasorelaxant effects without any chronotropic property. Interestingly, the mixture exerted higher cytoprotective effects and antioxidant activities. Moreover, the mixture exerted an inotropic effect similar to each single extract, while it revealed an intrinsic negative chronotropic activity different from the single extract; its relaxant activity was higher than that of each single extract. In conclusion OEE and HSE mixture has a good potential for pharmaceutical and nutraceutical application, thanks to the synergistic effects of the single phytochemicals. PMID:26180582

Comparative Study of Electronic Structure and Magnetic Properties of Osmate Double Perovskites: Ca2FeOsO6 versus Ca2Co(Ni)OsO6

NASA Astrophysics Data System (ADS)

Samanta, Kartik; Saha-Dasgupta, Tanusri

2018-04-01

Employing density functional theory, we study the trend in the electronic and magnetic properties of 3d-5d double perovskites, upon varying the 3d element for a fixed choice of 5d element, namely Ca2BOsO6 (B = Fe/Co/Ni). While all three compounds are reported to be ferrimagnets, the magnetic transition temperature of Ca2FeOsO6 is reported to be 2-2.4 times larger than that of Ca2CoOsO6 or Ca2NiOsO6. Our first-principles study provides microscopic insight into this trend. This trend is found to be caused by the downward shift in the position of d level energies of the B site element with respect to that of the Os t2g level upon moving across the 3d series from Fe to Co and Ni. This in turn changes the nominal valence of the Os ion from 5+ in Ca2FeOsO6 to 6+ in Ca2CoOsO6 and Ca2NiOsO6, resulting in differing superexchange paths between Ca2FeOsO6 and Ca2Co(Ni)OsO6, and additionally enabling the hybridization-mechanism-driven magnetism in Ca2FeOsO6. These together significantly enhance the magnetic transition temperature in Ca2FeOsO6 compared with that in Ca2Co(Ni)OsO6.

Quantitative comparison of the spreading and invasion of radial growth phase and metastatic melanoma cells in a three-dimensional human skin equivalent model.

PubMed

Haridas, Parvathi; McGovern, Jacqui A; McElwain, Sean D L; Simpson, Matthew J

2017-01-01

Standard two-dimensional (2D) cell migration assays do not provide information about vertical invasion processes, which are critical for melanoma progression. We provide information about three-dimensional (3D) melanoma cell migration, proliferation and invasion in a 3D melanoma skin equivalent (MSE) model. In particular, we pay careful attention to compare the structure of the tissues in the MSE with similarly-prepared 3D human skin equivalent (HSE) models. The HSE model is identically prepared to the MSE model except that melanoma cells are omitted. Using the MSE model, we examine melanoma migration, proliferation and invasion from two different human melanoma cell lines. One cell line, WM35, is associated with the early phase of the disease where spreading is thought to be confined to the epidermis. The other cell line, SK-MEL-28, is associated with the later phase of the disease where spreading into the dermis is expected. 3D MSE and HSE models are constructed using human de-epidermised dermis (DED) prepared from skin tissue. Primary fibroblasts and primary keratinocytes are used in the MSE and HSE models to ensure the formation of a stratified epidermis, with a well-defined basement membrane. Radial spreading of cells across the surface of the HSE and MSE models is observed. Vertical invasion of melanoma cells downward through the skin is observed and measured using immunohistochemistry. All measurements of invasion are made at day 0, 9, 15 and 20, providing detailed time course data. Both HSE and MSE models are similar to native skin in vivo , with a well-defined stratification of the epidermis that is separated from the dermis by a basement membrane. In the HSE and MSE we find fibroblast cells confined to the dermis, and differentiated keratinocytes in the epidermis. In the MSE, melanoma cells form colonies in the epidermis during the early part of the experiment. In the later stage of the experiment, the melanoma cells in the MSE invade deeper into the tissues. Interestingly, both the WM35 and SK-MEL-28 melanoma cells lead to a breakdown of the basement membrane and eventually enter the dermis. However, these two cell lines invade at different rates, with the SK-MEL-28 melanoma cells invading faster than the WM35 cells. The MSE and HSE models are a reliable platform for studying melanoma invasion in a 3D tissue that is similar to native human skin. Interestingly, we find that the WM35 cell line, that is thought to be associated with radial spreading only, is able to invade into the dermis. The vertical invasion of melanoma cells into the dermal region appears to be associated with a localised disruption of the basement membrane. Presenting our results in terms of time course data, along with images and quantitative measurements of the depth of invasion extends previous 3D work that has often been reported without these details.

Quantitative comparison of the spreading and invasion of radial growth phase and metastatic melanoma cells in a three-dimensional human skin equivalent model

PubMed Central

Haridas, Parvathi; McGovern, Jacqui A.; McElwain, Sean D.L.

2017-01-01

Background Standard two-dimensional (2D) cell migration assays do not provide information about vertical invasion processes, which are critical for melanoma progression. We provide information about three-dimensional (3D) melanoma cell migration, proliferation and invasion in a 3D melanoma skin equivalent (MSE) model. In particular, we pay careful attention to compare the structure of the tissues in the MSE with similarly-prepared 3D human skin equivalent (HSE) models. The HSE model is identically prepared to the MSE model except that melanoma cells are omitted. Using the MSE model, we examine melanoma migration, proliferation and invasion from two different human melanoma cell lines. One cell line, WM35, is associated with the early phase of the disease where spreading is thought to be confined to the epidermis. The other cell line, SK-MEL-28, is associated with the later phase of the disease where spreading into the dermis is expected. Methods 3D MSE and HSE models are constructed using human de-epidermised dermis (DED) prepared from skin tissue. Primary fibroblasts and primary keratinocytes are used in the MSE and HSE models to ensure the formation of a stratified epidermis, with a well-defined basement membrane. Radial spreading of cells across the surface of the HSE and MSE models is observed. Vertical invasion of melanoma cells downward through the skin is observed and measured using immunohistochemistry. All measurements of invasion are made at day 0, 9, 15 and 20, providing detailed time course data. Results Both HSE and MSE models are similar to native skin in vivo, with a well-defined stratification of the epidermis that is separated from the dermis by a basement membrane. In the HSE and MSE we find fibroblast cells confined to the dermis, and differentiated keratinocytes in the epidermis. In the MSE, melanoma cells form colonies in the epidermis during the early part of the experiment. In the later stage of the experiment, the melanoma cells in the MSE invade deeper into the tissues. Interestingly, both the WM35 and SK-MEL-28 melanoma cells lead to a breakdown of the basement membrane and eventually enter the dermis. However, these two cell lines invade at different rates, with the SK-MEL-28 melanoma cells invading faster than the WM35 cells. Discussion The MSE and HSE models are a reliable platform for studying melanoma invasion in a 3D tissue that is similar to native human skin. Interestingly, we find that the WM35 cell line, that is thought to be associated with radial spreading only, is able to invade into the dermis. The vertical invasion of melanoma cells into the dermal region appears to be associated with a localised disruption of the basement membrane. Presenting our results in terms of time course data, along with images and quantitative measurements of the depth of invasion extends previous 3D work that has often been reported without these details. PMID:28890854

Rhenium-osmium systematics of calcium-aluminium-rich inclusions in carbonaceous chondrites

USGS Publications Warehouse

Becker, H.; Morgan, J.W.; Walker, R.J.; MacPherson, G.J.; Grossman, J.N.

2001-01-01

The Re-Os isotopic systematics of calcium-aluminium-rich inclusions (CAIs) in chondrites were investigated in order to shed light on the behavior of the Re-Os system in bulk chondrites, and to constrain the timing of chemical fractionation in primitive chondrites. CAIs with relatively unfractionated rare earth element (REE) patterns (groups I, III, V, VI) define a narrow range of 187Re/188Os (0.3764-0.4443) and 187Os/188Os (0.12599-0.12717), and high but variable Re and Os abundances (3209-41,820 ppb Os). In contrast, CAIs that show depletions in highly refractory elements and strongly fractionated REE patterns (group II) also show a much larger range in 187Re/188Os (0.409-0.535) and 187Os/188Os (0.12695-0.13770), and greater than an order of magnitude lower Re and Os abundances than other groups (e.g., 75.7-680.2 ppb Os). Sixteen bulk CAIs and CAI splits plot within analytical uncertainty of a 4558 Ga reference isochron, as is expected for materials of this antiquity. Eight samples, however, plot off the isochron. Several possible reasons for these deviations are discussed. Data for multiple splits of one CAI indicate that the nonisochronous behavior for at least this CAI is the result of Re-Os reequilibration at approximately 1.6 Ga. Thus, the most likely explanation for the deviations of most of the nonisochronous CAIs is late-stage open-system behavior of Re and Os in the asteroidal environment. The 187Os/188Os-Os systematics of CAIs are consistent with previous models that indicate group II CAIs are mixtures of components that lost the bulk of their highly refractory elements in a previous condensation event and a minor second component that provided refractory elements at chondritic relative proportions. The high Re/Os of group II CAIs relative to other CAIs and chondrite bulk rocks may have been caused by variable mobilization of Re and Os during medium- to low-temperature parent body alteration ??4.5 Ga ago. This model is favored over nebular models, which pose several difficulties. The narrow range of 187Os/188Os in group I, III, V, and VI bulk CAIs, and the agreement with 187Os/188Os of whole rock carbonaceous chondrites suggest that on a bulk inclusion scale, secondary alteration only modestly fractionated Re/Os in these CAIs. The average of 187Os/188Os for group I, III, V, and VI CAIs is indistinguishable from average CI chondrites, indicating a modern solar system value for 187Os/188Os of 0.12650, corresponding to a 187Re/188Os of 0.3964. Copyright ?? 2001 Elsevier Science Ltd.

HSE12 implementation in libxc

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moussa, Jonathan E.

2013-05-13

This piece of software is a new feature implemented inside an existing open-source library. Specifically, it is a new implementation of a density functional (HSE, short for Heyd-Scuseria-Ernzerhof) for a repository of density functionals, the libxc library. It fixes some numerical problems with existing implementations, as outlined in a scientific paper recently submitted for publication. Density functionals are components of electronic structure simulations, which model properties of electrons inside molecules and crystals.

PubMed Central

SENNAROĞLU, G.; YÜCEL, E.; BELGIN, E.; MANCINI, P.

2015-01-01

SUMMARY The aim of this study was to investigate the amount of binaural squelch effect (BSE) and head shadow effect (HSE) in children who use unilateral cochlear implants (CI) and contralateral hearing aids (HA). The study group consisted of 19 CI recipient children who consistently wore a contralateral HA. Speech sounds were used to evaluate speech perception performance in noise. Testing was performed in three listening conditions: (1) bimodal listening with noise source on HA side; (2) CI only with noise source contralaterally (HA off); (3) CI only with noise source on the CI side. Statistical analysis revealed a significant difference between the three listening conditions and post hoc tests indicated significant differences for all pairwise comparisons (p < 0.001). The average BSE and HSE were 11.8% and 17.1% respectively. The majority of bimodal CI users showed BSE and HSE with significant speech perception improvement in the presence of noise. PMID:26824917

[Work-related stress and psychological distress assessment in urban and suburban public transportation companies].

PubMed

Romeo, L; Lazzarini, G; Farisè, E; Quintarelli, E; Riolfi, A; Perbellini, L

2012-01-01

The risk of work-related stress has been determined in bus drivers and workers employed in the service department of two urban and suburban public transportation companies. The INAIL evaluation method (Check list and HSE indicator tool) was used. The GHQ-12 questionnaire, which is widely used to assess the level of psychological distress, was also employed. 81.9% of workers involved in the survey answered both the HSE indicator tool and the GHQ-12 questionnaire. The Check list evaluation showed an increase in quantifiable company stress indicators while close examination using the HSE indicator tool demonstrated critical situations for all the subscales, with the control subscales more problematic in bus drivers. The demand, manager's support, relationships and change subscales were most associated with psychological distress in bus drivers, while relationships, role, change and demand subscales were negatively related in workers of the service department.

Do Hostile School Environments Promote Social Deviance by Shaping Neural Responses to Social Exclusion?

PubMed

Schriber, Roberta A; Rogers, Christina R; Ferrer, Emilio; Conger, Rand D; Robins, Richard W; Hastings, Paul D; Guyer, Amanda E

2018-03-01

The present study examined adolescents' neural responses to social exclusion as a mediator of past exposure to a hostile school environment (HSE) and later social deviance, and whether family connectedness buffered these associations. Participants (166 Mexican-origin adolescents, 54.4% female) reported on their HSE exposure and family connectedness across Grades 9-11. Six months later, neural responses to social exclusion were measured. Finally, social deviance was self-reported in Grades 9 and 12. The HSE-social deviance link was mediated by greater reactivity to social deviance in subgenual anterior cingulate cortex, a region from the social pain network also implicated in social susceptibility. However, youths with stronger family bonds were protected from this neurobiologically mediated path. These findings suggest a complex interplay of risk and protective factors that impact adolescent behavior through the brain. © 2018 Society for Research on Adolescence.

New Norwegian HSE standard for the offshore industry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huse, J.R.

1996-12-31

NORSOK (The competitive standing of the Norwegian offshore sector) is the Norwegian industry initiative to add value, reduce cost and lead time and remove unnecessary activities in offshore field developments and operations. The NORSOK standards are developed by the Norwegian petroleum industry as a part of the NORSOK initiative and are jointly issued by the Norwegian Oil Industry Association and the Federation of Norwegian Engineering Industries. The purpose of the industry standard is to replace the individual oil company specifications for use in existing and future petroleum industry developments, subject to the individual company`s review and application. The NORSOK Health,more » Safety and Environment (HSE) standards covers: Technical Safety, Working Environment, Environmental Care, HSE during Construction. The standards are now being used in ongoing offshore development projects, and the experience with standards shows that the principle aim is being met. The development of standards continues, implementing experience gained.« less

New safety rules challenge U. K. operators, regulators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hudson, J.

1994-08-15

Offshore safety regulations based on lessons learned from the Piper Alpha blast of 1988 have been in operation in the U.K. for a year. The Offshore Installations (Safety Case) Regulations 1992 make operators of fixed and mobile installations (the duty holders'') responsible for producing a formal safety assessment, or safety case, for each installation. After the end of November 1995 it will be an offense to operate an installation without a safety case which has been approved by the government's Health and Safety Executive (HSE). Producing safety cases for installations is a major task for duty holder, while assessing themmore » is a huge under taking for HSE's Offshore Safety Division (OSD). This paper reviews how HSE has established management arrangements to handle safety cases, considers progress in assessment, highlights some of the important lessons learned, and look to the future.« less

Osmium isotope evidence for a large Late Triassic impact event

PubMed Central

Sato, Honami; Onoue, Tetsuji; Nozaki, Tatsuo; Suzuki, Katsuhiko

2013-01-01

Anomalously high platinum group element concentrations have previously been reported for Upper Triassic deep-sea sediments, which are interpreted to be derived from an extraterrestrial impact event. Here we report the osmium (Os) isotope fingerprint of an extraterrestrial impact from Upper Triassic chert successions in Japan. Os isotope data exhibit a marked negative excursion from an initial Os isotope ratio (187Os/188Osi) of ∼0.477 to unradiogenic values of ∼0.126 in a platinum group element-enriched claystone layer, indicating the input of meteorite-derived Os into the sediments. The timing of the Os isotope excursion coincides with both elevated Os concentrations and low Re/Os ratios. The magnitude of this negative Os isotope excursion is comparable to those found at Cretaceous–Paleogene boundary sites. These geochemical lines of evidence demonstrate that a large impactor (3.3–7.8 km in diameter) produced a global decrease in seawater 187Os/188Os ratios in the Late Triassic. PMID:24036603

Transactivation of involucrin, a marker of differentiation in keratinocytes, by lens epithelium-derived growth factor (LEDGF).

PubMed

Kubo, E; Fatma, N; Sharma, P; Shinohara, T; Chylack, L T; Akagi, Y; Singh, D P

2002-07-26

Human involucrin (hINV), first appears in the cytosol of keratinocytes and ultimately cross-linked to membrane proteins via transglutaminase and forms a protective barrier as an insoluble envelope beneath the plasma membrane. Although the function and evolution of involucrin is known, the regulation of its gene expression is not well understood. An analysis of the hINV gene sequence, upstream of the transcription start site (-534 to +1 nt) revealed the presence of potential sites for binding of lens epithelium-derived growth factor (LEDGF); stress response element (STRE; A/TGGGGA/T) and heat shock element (HSE; nGAAn). We reported earlier that LEDGF activates stress-associated genes by binding to these elements and elevates cellular resistance to various stresses. Here, gel-shift and super-shift assays confirm the binding of LEDGF to the DNA fragments containing HSEs and STREs that are present in the involucrin gene promoter. Furthermore, hINV promoter linked to CAT reporter gene, cotransfected in human corneal simian virus 40-transformed keratinocytes (HCK), was transactivated by LEDGF significantly. In contrast, the activity of hINV promoter bearing mutations at the WT1 (containing HSE and STRE), WT2 (containing STRE) and WT3 (containing STRE) binding sites was diminished. In addition, in HCK cell over-expressing LEDGF, the levels of hINV mRNA and hINV protein are increased by four to five-fold. LEDGF is inducible to oxidants. Cells treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), known to stimulate production of H(2)O(2), showed higher levels of LEDGF mRNA. Furthermore, our immunohistochemical studies revealed that hINV protein is found in the cytoplasm of HCK cells over-expressing LEDGF, but not detectable in the normal HCK cells or HCK cells transfected with vector. This regulation appears to be physiologically important, as over-expression of HCK with LEDGF increases the expression of the endogenous hINV gene and may provide new insight to understand the molecular mechanism of transcriptional regulation of this gene. LEDGF may play an important role in establishing an important barrier in corneal keratinocytes by maintaining epidermal turn-over rate, and protecting HCKs against stress.

OsDREB2A, a Rice Transcription Factor, Significantly Affects Salt Tolerance in Transgenic Soybean

PubMed Central

Ma, Qi-bin; Yang, Cun-yi; Mu, Ying-hui; Suo, Hai-cui; Luo, Lai-hui; Nian, Hai

2013-01-01

The dehydration responsive element binding (DREB) transcription factors play an important role in regulating stress-related genes. OsDREB2A, a member of the DREBP subfamily of AP2/ERF transcription factors in rice (Oryza sativa), is involved in the abiotic stress response. OsDREB2A expression is induced by drought, low-temperature and salt stresses. Here, we report the ability of OsDREB2A to regulate high-salt response in transgenic soybean. Overexpressing OsDREB2A in soybeans enhanced salt tolerance by accumulating osmolytes, such as soluble sugars and free proline, and improving the expression levels of some stress-responsive transcription factors and key genes. The phenotypic characterization of transgenic soybean were significantly better than those of wild-type (WT). Electrophoresis mobility shift assay (EMSA) revealed that the OsDREB2A can bind to the DRE core element in vitro. These results indicate that OsDREB2A may participate in abiotic stress by directly binding with DRE element to regulate the expression of downstream genes. Overexpression of OsDREB2A in soybean might be used to improve tolerance to salt stress. PMID:24376625

A Bioengineered Human Skin Equivalent (HSE) for the Evaluation of Protectants

DTIC Science & Technology

2006-11-01

agonist clofibrate to the growth media. Medium supplemented with 25 μM palmitic acid , 15 μM linoleic acid , 25 μM oleic acid , 7 μM arachidonic acid , 0.25...granules (indicated by arrows). Fig. 6: A cross section of the HSE with lipids, ascorbic acid and clofibrate supplementation. The combination of... Clofibrate , Ascorbic Acid and Lipids Compared With the Lipid Profile of Native Human Skin. Clofibrate 300 μM Lipid class Control No ascorbic

Methods of defining hypertension in electronic medical records: validation against national survey data.

PubMed

Peng, Mingkai; Chen, Guanmin; Kaplan, Gilaad G; Lix, Lisa M; Drummond, Neil; Lucyk, Kelsey; Garies, Stephanie; Lowerison, Mark; Weibe, Samuel; Quan, Hude

2016-09-01

Electronic medical records (EMR) can be a cost-effective source for hypertension surveillance. However, diagnosis of hypertension in EMR is commonly under-coded and warrants the needs to review blood pressure and antihypertensive drugs for hypertension case identification. We included all the patients actively registered in The Health Improvement Network (THIN) database, UK, on 31 December 2011. Three case definitions using diagnosis code, antihypertensive drug prescriptions and abnormal blood pressure, respectively, were used to identify hypertension patients. We compared the prevalence and treatment rate of hypertension in THIN with results from Health Survey for England (HSE) in 2011. Compared with prevalence reported by HSE (29.7%), the use of diagnosis code alone (14.0%) underestimated hypertension prevalence. The use of any of the definitions (38.4%) or combination of antihypertensive drug prescriptions and abnormal blood pressure (38.4%) had higher prevalence than HSE. The use of diagnosis code or two abnormal blood pressure records with a 2-year period (31.1%) had similar prevalence and treatment rate of hypertension with HSE. Different definitions should be used for different study purposes. The definition of 'diagnosis code or two abnormal blood pressure records with a 2-year period' could be used for hypertension surveillance in THIN. © The Author 2015. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Acyclovir resistant acute herpes simplex encephalitis associated with acute retinal necrosis: A case report and review of the literature.

PubMed

Ogura, Haruchika; Fukae, Jiro; Kimura, Satoshi; Aoki, Mikiko; Nabeshima, Kazuki; Tsuboi, Yoshio

2017-05-27

A 55-year-old man was admitted to our hospital for investigation of high fever, decreased consciousness and bilateral visual impairment. His cerebrospinal fluid analysis revealed pleocytosis of mononuclear cells and an increased protein concentration. FLAIR images revealed multiple high-intensity lesions in the frontal lobe, part of which was enhanced with gadolinium. Despite initiating treatment with acyclovir and corticosteroids, his consciousness and visual acuity deteriorated. Immunopathological examination of brain biopsies showed numerous herpes simplex virus type 2-positive neurons and macrophages, leading to a diagnosis of herpes simplex encephalitis (HSE). Fundoscopic examination revealed multiple foci of retinitis with vasculopathies, and inflammation in the anterior chamber and vitreous, indicating acute retinal necrosis (ARN). Foscarnet treatment was initiated in place of acyclovir and his consciousness improved, with a slight improvement in visual acuity. ARN is typically caused by a herpes virus infection limited to the eyeball, and rarely in combination with HSE. In such cases, there is a latency of approximately 2-4 weeks between ARN and the onset of encephalitis. Our case is unique in that HSE and ARN developed simultaneously, and it highlights that there may not always be a latency between the onsets of the two disorders. Finally, foscarnet should be considered in cases of HSE and ARN with acyclovir resistance.

Siderophile element constraints on the origin of the Moon

PubMed Central

Walker, Richard J.

2014-01-01

Discovery of small enrichments in 182W/184W in some Archaean rocks, relative to modern mantle, suggests both exogeneous and endogenous modifications to highly siderophile element (HSE) and moderately siderophile element abundances in the terrestrial mantle. Collectively, these isotopic enrichments suggest the formation of chemically fractionated reservoirs in the terrestrial mantle that survived the putative Moon-forming giant impact, and also provide support for the late accretion hypothesis. The lunar mantle sources of volcanic glasses and basalts were depleted in HSEs relative to the terrestrial mantle by at least a factor of 20. The most likely explanations for the disparity between the Earth and Moon are either that the Moon received a disproportionately lower share of late accreted materials than the Earth, such as may have resulted from stochastic late accretion, or the major phase of late accretion occurred prior to the Moon-forming event, and the putative giant impact led to little drawdown of HSEs to the Earth's core. High precision determination of the 182W isotopic composition of the Moon can help to resolve this issue. PMID:25114313

Franck Condon shift assessment in 2D MoS₂.

PubMed

Gupta, Sunny; Shirodkar, Sharmila N; Kaplan, Daniel; Swaminathan, Venkataraman; Yakobson, Boris I

2018-01-19

Optical spectroscopy (OS) techniques are often coupled with first-principles density functional theoretical (DFT) calculations for determining the precise influence of defects on the electronic and structural properties of two dimensional (2D) TMDs. Such calculations are carried out presuming there is little or no effect of vibrational transitions on the observed electronic spectrum. However, if the effect of change in vibrational energy [Franck Condon (FC) shift] associated with such a transition is large, it could possibly lead to a different origin for the observed peak. One such instance is the attribution of the 0.75 eV cathodoluminescence peak by Fabbri et. al. [Nat. Commun. 7, 13044 (2016)]. to an optical transition from an S vacancy level in the band gap, under the assumption that the FC shift is negligible. Here, by first principles constrained DFT calculations using hybrid HSE06 functional we show that this combined prediction of OS and DFT calculations is valid for 2D MoS2 since the FC shift associated with electronic transitions from a sulfur vacancy is, indeed, small ~28 meV. Based on our calculations we conclude that it is reasonable to make a direct connection between DFT calculations and optical spectroscopy techniques in this material, hence, establishing a one to one relation between defect related emission bands and electronic transitions from the defect levels. © 2018 IOP Publishing Ltd.

Franck Condon shift assessment in 2D MoS2

NASA Astrophysics Data System (ADS)

Gupta, Sunny; Shirodkar, Sharmila N.; Kaplan, Daniel; Swaminathan, Venkataraman; Yakobson, Boris I.

2018-03-01

Optical spectroscopy (OS) techniques are often coupled with first-principles density functional theoretical (DFT) calculations for determining the precise influence of defects on the electronic and structural properties of two-dimensional (2D) transition metal dichalcogenides. Such calculations are carried out presuming there is little or no effect of vibrational transitions on the observed electronic spectrum. However, if the effect of change in vibrational energy (Franck Condon (FC) shift) associated with such a transition is large, it could possibly lead to a different origin for the observed peak. One such instance is the attribution of the 0.75 eV cathodoluminescence peak by Fabbri et al (2016 Nat. Commun. 7 13044) to an optical transition from an S vacancy level in the band gap, under the assumption that the FC shift is negligible. Here, by first principles constrained DFT calculations using hybrid HSE06 functional we show that this combined prediction of OS and DFT calculations is valid for 2D MoS2 since the FC shift associated with electronic transitions from a sulfur vacancy is indeed small ~28 meV. Based on our calculations we conclude that it is reasonable to make a direct connection between DFT calculations and optical spectroscopy techniques in this material, hence, establishing a one to one relation between defect related emission bands and electronic transitions from the defect levels.

Imaging techniques for evaluation of the uterine cavity and endometrium in premenopausal patients before minimally invasive surgery.

PubMed

Dueholm, Margit; Lundorf, Erik; Olesen, Frede

2002-06-01

A literature review compared the diagnostic effectiveness and accuracy of transvaginal sonography (TVS) hysterosonographic examination (HSE), hysteroscopy (HY), and magnetic resonance imaging (MRI) in abnormalities of the uterine cavity and endometrium in premenopausal patients referred to surgery and women with abnormal uterine bleeding. The studies varied much in terms of patient selection, number of observers, blinding and experience of observers, and definition of abnormality criteria. The diagnostic effectiveness of the techniques reviewed varied: TVS only reached intermediate quality levels as a diagnostic tool for exclusion of uterine cavity abnormalities and no data support that MRI, TVS, HY, or HSE may exclude hyperplasia without concomitant endometrial sampling. HY and HSE were equally effective and apparently outperformed TVS, especially for identification of polyps. However, all techniques carried a significant number of false positive results. MRI does not satisfy current diagnostic demands for detection of endometrial abnormalities, but it is sufficiently accurate for submucous myoma (SM) evaluation. TVS, HSE, and HY carry much observer variation as opposed to MRI. In experienced hands TVS should be a first choice modality, but its precision and consistency fall short of current needs and it should therefore be supplemented by other techniques. HSE or HY performed by experienced clinicians should be used as supplements to TVS for exclusion of polyps. MRI can be recommended as the first choice modality for exact evaluation of SM uterine in-growth before advanced minimal invasive treatment of myomas. Clinicians should be aware that modern imaging techniques may yield highly idiosyncratic results when used by inexperienced staff, and efforts should be made to reduce such observer variation. Obstetricians & Gynecologists, Family Physicians. After completion of this article, the reader will be able to describe the diagnostic strengths and weaknesses of the various diagnostic tests in the evaluation of abnormal uterine bleeding and to compare the accuracy of each test to the others.

Early pathologic findings and long-term improvement in anti-Ma2-associated encephalitis.

PubMed

Blumenthal, D T; Salzman, K L; Digre, K B; Jensen, R L; Dunson, W A; Dalmau, J

2006-07-11

A 67-year-old man sequentially developed anti-Ma2-associated paraneoplastic encephalitis (PNE) and contralateral herpes simplex encephalitis (HSE). Brain biopsy 1 month before HSE revealed extensive infiltrates of T cells, B cells, and plasma cells. Most T cells expressed the cytotoxic granule-associated protein TIA-1 and the membranolytic protein granzyme-B. Although recovery was thought to be unlikely, treatment of the PNE with corticosteroids and resection of the associated lung cancer resulted in dramatic improvement for 21 months.

Deadlines set for new U. K. offshore safety rules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-12-14

This paper reports on new U.K. offshore safety regulations-inspired by Lord Cullen's 1990 report spawned by the 1987 Piper Alpha platform accident which will take effect May 31, 1993, for new installations. The U.K. Health and Safety Executive (HSE) said its proposed regulations, required for operators or owners to gain HSE approval for each fixed or mobile installation, was put before Parliament Nov. 27. That gives opposition parties 40 days to call for debate and possible amendment before the proposals become law.

Quality assurance for health and environmental chemistry: 1990

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gautier, M.A.; Gladney, E.S.; Koski, N.L.

1991-10-01

This report documents the continuing quality assurance efforts of the Health and Environmental Chemistry Group (HSE-9) at the Los Alamos National Laboratory. The philosophy, methodology, computing resources, and laboratory information management system used by the quality assurance program to encompass the diversity of analytical chemistry practiced in the group are described. Included in the report are all quality assurance reference materials used, along with their certified or consensus concentrations, and all analytical chemistry quality assurance measurements made by HSE-9 during 1990.

Effects of mother lode-type gold mineralization on 187Os/188Os and platinum group element concentrations in peridotite: Alleghany District, California

USGS Publications Warehouse

Walker, R.J.; Böhlke, J.K.; McDonough, W.F.; Li, Ji

2007-01-01

Osmium isotope compositions and concentrations of Re, platinum group elements (PGE), and Au were determined for host peridotites (serpentinites and barzburgites) and hydrothermally altered ultramafic wall rocks associated with Mother Lode-type hydrothermal gold-quartz vein mineralization in the Alleghany district, California. The host peridotites have Os isotope compositions and Re, PGE, and Au abundances typical of the upper mantle at their presumed formation age during the late Proterozoic or early Paleozoic. The hydrothermally altered rocks have highly variable initial Os isotope compositions with ??os, values (% deviation of 187OS/188OS from the chondritic average calculated for the approx. 120 Ma time of mineralization) ranging from -1.4 to -8.3. The lowest Os isotope compositions are consistent with Re depletion of a chondritic source (e.g., the upper mantle) at ca. 1.6 Ga. Most of the altered samples are enriched in Au and have depleted and fractionated abundances of Re and PGE relative to their precursor peridotites. Geoehemical characteristics of the altered samples suggest that Re and some PGE were variably removed from the ultramafic rocks during the mineralization event. In addition to Re, the Pt and Pd abundances of the most intensely altered rocks appear to have been most affected by mineralization. The 187Os-depleted isotopic compositions of some altered rocks are interpreted to be a result of preferential 187Os loss via destruction of Re-rich phases during the event. For these rocks, Os evidently is not a useful tracer of the mineralizing fluids. The results do, however, provide evidence for differential mobility of these elements, and mobility of 187Os relative to the initial bulk Os isotope composition during hydrothermal metasomatic alteration of ultramafic rocks. ?? 2007 Society of Economic Geologists, Inc.

The Chelyabinsk Fall Highly Siderophile Element Abundance and 187Os/188Os Composition and Comparison with Ordinary and Carbonaceous Chondrites

NASA Astrophysics Data System (ADS)

Day, J. M. D.; Corder, C. A.; Dhaliwal, J. K.; Liu, Y.; Taylor, L. A.

2014-09-01

New osmium isotope and highly siderophile element abundance data are presented for the Chelyabinsk ordinary chondrite fall (February 2013) and placed into context with new data for ordinary and carbonaceous chondrites.

Osmium-Isotope and Platinum-Group-Element Systematics of Impact-Melt Rocks, Chesapeake Bay Impact Structure, Virginia, USA

NASA Technical Reports Server (NTRS)

Lee, Seung Ryeol; Wright Horton, J., Jr.; Walker, Richard J.

2005-01-01

Osmium (Os) isotopes and platinum-group elements (PGEs) are useful for geochemically identifying a meteoritic component within impact structures, because meteorites are typically characterized by low (187)Os/(188)Os ratios and high PGE concentrations. In contrast, most types of crustal target rocks have high radiogenic Os and very low PGE concentrations. We have examined Os isotope and PGE systematics of impact-melt rocks and pre-impact target rocks from a 2004 test hole in the late Eocene Chesapeake Bay impact structure and from nearby coreholes. Our goal is to determine the proportion of the projectile component in the melt rock Additional information is included in the original extended abstract.

Management of occupational health risks in small-animal veterinary practices.

PubMed

D'Souza, Eva; Barraclough, Richard; Fishwick, David; Curran, Andrew

2009-08-01

Small-animal work is a major element of veterinary practice in the UK and may be hazardous, with high levels of work-related injuries and ill-health reported in Australia and USA. There are no studies addressing the management of occupational health risks arising from small-animal work in the UK. To investigate the sources of health and safety information used and how health and safety and 12 specific occupational health risks are managed by practices. A cross-sectional postal survey of all small-animal veterinary practices in Hampshire. A response was mandatory as this was a Health & Safety Executive (HSE) inspection activity. A total of 118 (100%) practices responded of which 93 were eligible for inclusion. Of these, 99 and 86%, respectively, were aware of the Royal College of Veterinary Surgeons (RCVS) practice standards and had British Small Animal Veterinary Association (BSAVA) staff members, while only 51% had previous contact with HSE (publications, advice and visit). Ninety per cent had health and safety policies, but only 31% had trained responsible staff in health and safety. Specific health hazards such as occupational allergens and computer use were relatively overlooked both by practices and the RCVS/BSAVA guidance available in 2002. Failings in active health risk management systems could be due to a lack of training to ensure competence in those with responsibilities. Practices rely on guidance produced by their professional bodies. Current RCVS guidance, available since 2005, has remedied some previous omissions, but further improvements are recommended.

Magnesium acceptor in gallium nitride. II. Koopmans-tuned Heyd-Scuseria-Ernzerhof hybrid functional calculations of its dual nature and optical properties

NASA Astrophysics Data System (ADS)

Demchenko, D. O.; Diallo, I. C.; Reshchikov, M. A.

2018-05-01

The problem of magnesium acceptor in gallium nitride is that experimental photoluminescence measurements clearly reveal a shallow defect state, while most theoretical predictions favor a localized polaronic defect state. To resolve this contradiction, we calculate properties of magnesium acceptor using the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional, tuned to fulfill the generalized Koopmans condition. We test Koopmans tuning of HSE for defect calculations in GaN using two contrasting test cases: a deep state of gallium vacancy and a shallow state of magnesium acceptor. The obtained parametrization of HSE allows calculations of optical properties of acceptors using neutral defect-state eigenvalues, without relying on corrections due to charged defects in periodic supercells. Optical transitions and vibrational properties of M gGa defect are analyzed to bring the dual (shallow and deep) nature of this defect into accord with experimental photoluminescence measurements of the ultraviolet band in Mg-doped GaN samples.

Pharmacoepidemiology resources in Ireland-an introduction to pharmacy claims data.

PubMed

Sinnott, Sarah-Jo; Bennett, Kathleen; Cahir, Caitriona

2017-11-01

Administrative health data, such as pharmacy claims data, present a valuable resource for conducting pharmacoepidemiological and health services research. Often, data are available for whole populations allowing population level analyses. Moreover, their routine collection ensures that the data reflect health care utilisation in the real-world setting compared to data collected in clinical trials. The Irish Health Service Executive-Primary Care Reimbursement Service (HSE-PCRS) community pharmacy claims database is described. The availability of demographic variables and drug-related information is discussed. The strengths and limitations associated using this database for conducting research are presented, in particular, internal and external validity. Examples of recently conducted research using the HSE-PCRS pharmacy claims database are used to illustrate the breadth of its use. The HSE-PCRS national pharmacy claims database is a large, high-quality, valid and accurate data source for measuring drug exposure in specific populations in Ireland. The main limitation is the lack of generalisability for those aged <70 years and the lack of information on indication or outcome.

Chronic herpes simplex type-1 encephalitis with intractable epilepsy in an immunosuppressed patient.

PubMed

Laohathai, Christopher; Weber, Daniel J; Hayat, Ghazala; Thomas, Florian P

2016-02-01

Chronic herpes simplex virus type-1 encephalitis (HSE-1) is uncommon. Past reports focused on its association with prior documented acute infection. Here, we describe a patient with increasingly intractable epilepsy from chronic HSE-1 reactivation without history of acute central nervous system infection. A 49-year-old liver transplant patient with 4-year history of epilepsy after initiation of cyclosporine developed increasingly frequent seizures over 3 months. Serial brain magnetic resonance imaging showed left temporoparietal cortical edema that gradually improved despite clinical decline. Herpes simplex virus type-1 (HSV-1) DNA was detected in cerebrospinal fluid by polymerase chain reaction. Cerebrospinal fluid HSV-1&2 IgM was negative. Seizures were controlled after acyclovir treatment, and the patient remained seizure free at 1-year follow-up. Chronic HSE is a cause of intractable epilepsy, can occur without a recognized preceding acute phase, and the clinical course of infection may not directly correlate with neuroimaging changes.

A Screened Hybrid DFT Study of Actinide Oxides, Nitrides, and Carbides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wen, Xiaodong; Martin, Richard L.; Scuseria, Gustavo E.

2013-06-27

A systematic study of the structural, electronic, and magnetic properties of actinide oxides, nitrides, and carbides (AnX1–2 with X = C, N, O) is performed using the Heyd–Scuseria–Ernzerhof (HSE) hybrid functional. Our computed results show that the screened hybrid HSE functional gives a good description of the electronic and structural properties of actinide dioxides (strongly correlated insulators) when compared with available experimental data. However, there are still some problems reproducing the electronic properties of actinide nitrides and carbides (strongly correlated metals). In addition, in order to compare with the results by HSE, the structures, electronic, and magnetic properties of thesemore » actinide compounds are also investigated in the PBE and PBE+U approximation. Interestingly, the density of states of UN obtained with PBE compares well with the experimental photoemission spectra, in contrast to the hybrid approximation. This is presumably related to the need of additional screening in the Hartree–Fock exchange term of the metallic phases.« less

Functional analysis of Drosophila HSP70 promoter with different HSE numbers in human cells.

PubMed

Kust, Nadezda; Rybalkina, Ekaterina; Mertsalov, Ilya; Savchenko, Ekaterina; Revishchin, Alexander; Pavlova, Gali

2014-01-01

The activation of genetic constructs including the Drosophila hsp70 promoter with four and eight HSE sequences in the regulatory region has been described in human cells. The promoter was shown to be induced at lower temperatures compared to the human hsp70 promoter. The promoter activity increased after a 60-min heat shock already at 38 °C in human cells. The promoter activation was observed 24 h after heat shock for the constructs with eight HSEs, while those with four HSEs required 48 h. After transplantation of in vitro heat-shocked transfected cells, the promoter activity could be maintained for 3 days with a gradual decline. The promoter activation was confirmed in vivo without preliminary heat shock in mouse ischemic brain foci. Controlled expression of the Gdnf gene under a Drosophila hsp70 promoter was demonstrated. This promoter with four and eight HSE sequences in the regulatory region can be proposed as a regulated promoter in genetic therapeutic systems.

Numeracy Skills in Patients With Degenerative Disorders and Focal Brain Lesions

PubMed Central

Cappelletti, Marinella; Butterworth, Brian; Kopelman, Michael

2012-01-01

Objective: To characterize the numerical profile of patients with acquired brain disorders. Method: We investigated numeracy skills in 76 participants—40 healthy controls and 36 patients with neurodegenerative disorders (Alzheimer dementia, frontotemporal dementia, semantic dementia, progressive aphasia) and with focal brain lesions affecting parietal, frontal, and temporal areas as in herpes simplex encephalitis (HSE). All patients were tested with the same comprehensive battery of paper-and-pencil and computerized tasks assessing numerical abilities and calculation. Degenerative and HSE patients also performed nonnumerical semantic tasks. Results: Our results, based on nonparametric group statistics as well as on the analysis of individual patients, and all highly significant, show that: (a) all patients, including those with parietal lesions—a key brain area for numeracy processing—had intact processing of number quantity; (b) patients with impaired semantic knowledge had much better preserved numerical knowledge; and (c) most patients showed impaired calculation skills, with the exception of most semantic dementia and HSE patients. Conclusion: Our results allow us, for the first time, to characterize the numeracy skills in patients with a variety of neurological conditions and to suggest that the pattern of numerical performance can vary considerably across different neurological populations. Moreover, the selective sparing of calculation skills in most semantic dementia and HSE suggest that numerical abilities are an independent component of the semantic system. Finally, our data suggest that, besides the parietal areas, other brain regions might be critical to the understanding and processing of numerical concepts. PMID:22122516

Nonlinear electronic excitations in crystalline solids using meta-generalized gradient approximation and hybrid functional in time-dependent density functional theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sato, Shunsuke A.; Taniguchi, Yasutaka; Department of Medical and General Sciences, Nihon Institute of Medical Science, 1276 Shimogawara, Moroyama-Machi, Iruma-Gun, Saitama 350-0435

2015-12-14

We develop methods to calculate electron dynamics in crystalline solids in real-time time-dependent density functional theory employing exchange-correlation potentials which reproduce band gap energies of dielectrics; a meta-generalized gradient approximation was proposed by Tran and Blaha [Phys. Rev. Lett. 102, 226401 (2009)] (TBm-BJ) and a hybrid functional was proposed by Heyd, Scuseria, and Ernzerhof [J. Chem. Phys. 118, 8207 (2003)] (HSE). In time evolution calculations employing the TB-mBJ potential, we have found it necessary to adopt the predictor-corrector step for a stable time evolution. We have developed a method to evaluate electronic excitation energy without referring to the energy functionalmore » which is unknown for the TB-mBJ potential. For the HSE functional, we have developed a method for the operation of the Fock-like term in Fourier space to facilitate efficient use of massive parallel computers equipped with graphic processing units. We compare electronic excitations in silicon and germanium induced by femtosecond laser pulses using the TB-mBJ, HSE, and a simple local density approximation (LDA). At low laser intensities, electronic excitations are found to be sensitive to the band gap energy: they are close to each other using TB-mBJ and HSE and are much smaller in LDA. At high laser intensities close to the damage threshold, electronic excitation energies do not differ much among the three cases.« less

Rhenium - osmium heterogeneity of enriched mantle basalts explained by composition and behaviour of mantle-derived sulfides

NASA Astrophysics Data System (ADS)

Harvey, J.; Dale, C. W.; Gannoun, A.; Burton, K. W.

2010-12-01

Analyses of enriched mantle (EM) -basalts, using lithophile element-based isotope systems have long provided evidence for discrete, but variable mantle reservoirs [1]. Upon partial melting, the isotopic fingerprint of each reservoir is imparted upon the partial melt produced. However, recent work involving the Re-Os isotope systematics of EM-basalts [2] suggests that it may not be so simple to delimit these previously well defined mantle reservoirs; the “mantle zoo” [3] may contain more reservoirs than previously envisaged. However, a simple model, with varying contributions from two populations of compositionally distinct mantle sulfides can readily account for the observed heterogeneities in Re-Os isotope systematics of such basalts without additional mantle reservoirs. Rhenium-osmium elemental and isotopic analyses of individual sulfide grains separated from spinel lherzolites from Kilbourne Hole, NM, USA demonstrate that two discrete populations of mantle sulfide exist in terms of both Re-Os systematics and textural relationship with co-existing silicates. One population, with a rounded morphology, is preserved in silicate grains and typically possesses high [Os], low [Re] with unradiogenic, typically sub-chondritic, 187Os/188Os attributable to long term isolation in a low-Re environment. By contrast, irregular-shaped sulfides, preserved along silicate grain boundaries, possess low [Os], higher [Re] and a wider range of, but generally supra-chondritic, 187Os/188Os ([Os] typically ≤ 1-2 ppm, 187Os/188Os ≤ 0.3729; this study). This population is thought to represent metasomatic sulfide (e.g. [4,5]). Uncontaminated silicate phases contain negligible Os (<100 ppt) therefore the Os elemental and isotope composition of basalts is dominated by volumetrically insignificant sulfide ([Os] ≤ 37 ppm, this study). During the early stages of partial melting, supra-chondritic interstitial sulfides are mobilized and incorporated into the melt, adding their radiogenic 187Os/188Os signature. Only when sulfides armored within silicates are exposed to the melt through continued partial melting will enclosed sulfides add their high [Os] and unradiogenic 187Os/188Os to the aggregate melt. Platinum-group element data for whole rocks are also consistent with this scenario. The sequence of (i) addition of all the metasomatic sulfide, followed by (ii) the incorporation of small amounts of armored sulfide can thus account for the range of both [Os] and 187Os/188Os of EM-basalts worldwide without the need for contributions from additional silicate mantle reservoirs. References: [1] Zindler & Hart, (1986) Annu. Rev. Earth Planet. Sci. 14, 493-571. [2] Class et al. (2009) Earth Planet. Sci. Lett. 284, 219-227. [3] Stracke, et al. (2005) Geochem., Geophys., Geosys. 6, doi:10.1029/2004GC000824. [4] Burton et al., Earth Planet. Sci. Lett. (1999) 172, 311-322. [5] Alard et al., (2002) Earth Planet. Sci. Lett. 203, 651-663

Unravelling the effects of melt depletion and secondary infiltration on mantle Re-Os isotopes beneath the French Massif Central

NASA Astrophysics Data System (ADS)

Harvey, J.; Gannoun, A.; Burton, K. W.; Schiano, P.; Rogers, N. W.; Alard, O.

2010-01-01

Spinel lherzolite xenoliths from Mont Briançon, French Massif Central, retain evidence for multiple episodes of melt depletion and melt/fluid infiltration (metasomatism). Evidence for primary melt depletion is still preserved in the co-variation of bulk-rock major elements (MgO 38.7-46.1 wt.%; CaO 0.9-3.6 wt.%), and many samples yield unradiogenic bulk-rock Os isotope ratios ( 187Os/ 188Os = 0.11541-0.12626). However, many individual xenoliths contain interstitial glasses and melt inclusions that are not in equilibrium with the major primary minerals. Incompatible trace element mass balance calculations demonstrate that metasomatic components comprise a significant proportion of the bulk-rock budget for these elements in some rocks, ranging to as much as 25% of Nd and 40% of Sr Critically, for Re-Os geochronology, melt/fluid infiltration is accompanied by the mobilisation of sulfide. Consequently, bulk-rock isotope measurements, whether using lithophile (e.g. Rb-Sr, Sm-Nd) or siderophile (Re-Os) based isotope systems, may only yield a perturbed and/or homogenised average of these multiple events. Osmium mass balance calculations demonstrate that bulk-rock Os in peridotite is dominated by contributions from two populations of sulfide grain: (i) interstitial, metasomatic sulfide with low [Os] and radiogenic 187Os/ 188Os, and (ii) primary sulfides with high [Os] and unradiogenic 187Os/ 188Os, which have been preserved within host silicate grains and shielded from interaction with transient melts and fluid. The latter can account for >97% of bulk-rock Os and preserve geochronological information of the melt from which they originally precipitated as an immiscible liquid. The Re-depletion model ages of individual primary sulfide grains preserve evidence for melt depletion beneath the Massif Central from at least 1.8 Gyr ago despite the more recent metasomatic event(s).

Drilling, Completion, and Data Collection Plans An Assessment of Geological Carbon Sequestration Options in the Illinois Basin: Phase III

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malkewicz, Nicholas; Kirksey, Jim; Finley, Robert

2015-05-01

Executive Summary The Illinois Basin – Decatur Project (IBDP) is managed by the Midwest Geological Sequestration Consortium (MGSC) and is led by the Illinois State Geological Survey (ISGS) at the University of Illinois. The project site is located on the Archer Daniels Midland Company (ADM) property in Decatur, Illinois, and is a fully integrated carbon capture and storage (CCS) project that uses CO₂ captured from the ethanol-producing fermentation process at the ADM corn-processing plant (Finley et. al., 2013). IBDP has a goal of injecting one million tonnes of CO₂ into the basal sands of the Mt. Simon Sandstone over amore » three-year period. This is a multifaceted project, and this report details the planning and results of the drilling, completions, well testing, log data acquisition, and the Health, Safety, and Environment (HSE) aspects of the project. Three deep wells were planned for the IBDP: • The injection well: Injection Well #1 (CCS1); • The monitoring well (both in-zone and above seal): Verification Well #1 (VW1); and • The geophone monitoring well: Geophysical Monitoring Well #1 (GM1). The detailed plans for these wells are attached to the appendices of this document. The wells were drilled successfully with little deviation from the original plans. The biggest change from the plan to execution was the need to adjust for larger-than-expected loss of circulation in the Potosi section of the Knox Formation. The completions reports also attached to this document detail the well constructions as they were actually built. Injectivity testing was carried out, and the perforating plans were adjusted based on the results. Additional perforations and acidizing were performed as a result of the injectivity testing. The testing plans are detailed in this report along with the actual testing results. The injectivity testing results were used in the modeling and simulation efforts. Detailed HSE plans were developed and implemented during the planning and execution phases of the project. The implementation included an HSE Bridging Document, which served to unify the HSE policies of the project partners and key subcontractors. The HSE plan and actual HSE results are presented in this document. There were no recordable HSE incidents during the project. A detailed logging program was developed based on project needs. The log data were acquired in accordance with the plan, and both the plan and log results are presented in this report. Log data were heavily utilized by the research staff, modelers, reservoir engineers, and for technical and permitting efforts. 5 Several key lessons were learned during the project: • Safety in operations and execution is paramount and is only achieved through proper planning and behavior control. The certainty of this was reinforced through implementation of this lesson and the resultant flawless HSE performance during the project. • Losses of drilling fluid circulation were larger than anticipated within the Potosi Formation. Circulation was only recovered through cementing the loss zones. • When possible, minimizing complexity in permit requirements and well designs is preferable. • The size of the wells were outside of the standard experience and expertise typical within the basin, and therefore required substantial planning and ramp-up of contractors and partners to meet project objectives. • With multiple stakeholders and research partners, establishing objectives and requirements early and adhering to change request procedures throughout the project are critical to manage competing data and sampling objectives that may be detrimental to overall progress. The well construction and completion operations were successfully executed, with all wells built in a manner that achieved excellent wellbore integrity. Log planning involved a number of stakeholders and technical specialists. Data collection from logging, coring, and testing was excellent. Time and effort spent with the associated contractors and suppliers to develop a well plan beyond normal scope proved highly successful, resulting in a well-construction and completion project that surpassed expectations. The world-class HSE results also demonstrate the commitment of all stakeholders in the project. The details follow in the body of this document« less

OsSLI1, a homeodomain containing transcription activator, involves abscisic acid related stress response in rice (Oryza sativa L.).

PubMed

Huang, Xi; Duan, Min; Liao, Jiakai; Yuan, Xi; Chen, Hui; Feng, Jiejie; Huang, Ji; Zhang, Hong-Sheng

2014-01-01

Homeodomain-leucine zipper type I (HD-Zip I) proteins are involved in the regulation of plant development and response to environmental stresses. In this study, OsSLI1 (Oryza sativa stress largely induced 1), encoding a member of the HD-Zip I subfamily, was isolated from rice. The expression of OsSLI1 was dramatically induced by multiple abiotic stresses and exogenous abscisic acid (ABA). In silico sequence analysis discovered several cis-acting elements including multiple ABREs (ABA-responsive element binding factors) in the upstream promoter region of OsSLI1. The OsSLI1-GFP fusion protein was localized in the nucleus of rice protoplast cells and the transcriptional activity of OsSLI1 was confirmed by the yeast hybrid system. Further, it was found that OsSLI1 expression was enhanced in an ABI5-Like1 (ABL1) deficiency rice mutant abl1 under stress conditions, suggesting that ABL1 probably negatively regulates OsSLI1 gene expression. Moreover, it was found that OsSLI1 was regulated in panicle development. Taken together, OsSLI1 may be a transcriptional activator regulating stress-responsive gene expression and panicle development in rice.

Both Cerebral and Hematopoietic Deficiencies in CCR2 Result in Uncontrolled Herpes Simplex Virus Infection of the Central Nervous System in Mice.

PubMed

Menasria, Rafik; Canivet, Coraline; Piret, Jocelyne; Gosselin, Jean; Boivin, Guy

2016-01-01

CCR2 is a chemokine receptor expressed on the surface of blood leukocytes, particularly «Ly6Chi» inflammatory monocytes and microglia. Signaling through this receptor is thought to influence the immune activity of microglia as well as monocytes egress from the bone marrow (BM) and their trafficking into the central nervous system (CNS) in several neurological diseases. During experimental herpes simplex virus 1 (HSV-1) encephalitis (HSE), CCR2 deficiency has been reported to exacerbate the outcome of the disease. However, the precise contribution of CCR2 expressed in cells of the CNS or peripheral monocytes in the protection against HSE remains unclear. To dissect the differential role of CCR2 during HSE, chimeric mice with receptor deficiency in the brain or blood cells were generated by transplanting wild-type (WT) C57BL/6 or CCR2-/- BM-derived cells in CCR2-/- (WT→CCR2-/-) and WT (CCR2-/-→WT) mice, respectively. Our results indicate that following intranasal infection with 1.2x106 plaque forming units of HSV-1, CCR2 deficiency in hematopoietic cells and, to a lesser extent, in CNS exacerbates the outcome of HSE. Mortality rates of CCR2-/- (71.4%) and CCR2-/-→WT (57.1%) mice were significantly higher than that of WT (15.3%; P<0.01 and P<0.05, respectively) but the difference did not reach statistical significance for WT→CCR2-/- animals (42.8%; P = 0.16). Both peripheral and CNS deficiencies in CCR2 resulted in increased infectious viral titers and wider dissemination of HSV antigens in the brain as well as an overproduction of inflammatory cytokines and chemokines including IL-1β, IL-6, CCL2, CCL3 and CCL5. Furthermore, CCR2 deficiency in the hematopoietic system altered monocytes egress from the BM and their recruitment to the CNS, which may contribute to the failure in HSV-1 containment. Collectively, these data suggest that CCR2 expressed on cells of CNS and especially on peripheral monocytes is important for the control of HSV-1 replication and inflammatory environment during experimental HSE.

Both Cerebral and Hematopoietic Deficiencies in CCR2 Result in Uncontrolled Herpes Simplex Virus Infection of the Central Nervous System in Mice

PubMed Central

Menasria, Rafik; Canivet, Coraline; Piret, Jocelyne; Gosselin, Jean; Boivin, Guy

2016-01-01

CCR2 is a chemokine receptor expressed on the surface of blood leukocytes, particularly «Ly6Chi» inflammatory monocytes and microglia. Signaling through this receptor is thought to influence the immune activity of microglia as well as monocytes egress from the bone marrow (BM) and their trafficking into the central nervous system (CNS) in several neurological diseases. During experimental herpes simplex virus 1 (HSV-1) encephalitis (HSE), CCR2 deficiency has been reported to exacerbate the outcome of the disease. However, the precise contribution of CCR2 expressed in cells of the CNS or peripheral monocytes in the protection against HSE remains unclear. To dissect the differential role of CCR2 during HSE, chimeric mice with receptor deficiency in the brain or blood cells were generated by transplanting wild-type (WT) C57BL/6 or CCR2-/- BM-derived cells in CCR2-/- (WT→CCR2-/-) and WT (CCR2-/-→WT) mice, respectively. Our results indicate that following intranasal infection with 1.2x106 plaque forming units of HSV-1, CCR2 deficiency in hematopoietic cells and, to a lesser extent, in CNS exacerbates the outcome of HSE. Mortality rates of CCR2-/- (71.4%) and CCR2-/-→WT (57.1%) mice were significantly higher than that of WT (15.3%; P<0.01 and P<0.05, respectively) but the difference did not reach statistical significance for WT→CCR2-/- animals (42.8%; P = 0.16). Both peripheral and CNS deficiencies in CCR2 resulted in increased infectious viral titers and wider dissemination of HSV antigens in the brain as well as an overproduction of inflammatory cytokines and chemokines including IL-1β, IL-6, CCL2, CCL3 and CCL5. Furthermore, CCR2 deficiency in the hematopoietic system altered monocytes egress from the BM and their recruitment to the CNS, which may contribute to the failure in HSV-1 containment. Collectively, these data suggest that CCR2 expressed on cells of CNS and especially on peripheral monocytes is important for the control of HSV-1 replication and inflammatory environment during experimental HSE. PMID:27930721

Protective effect of Hibiscus sabdariffa against serum/glucose deprivation-induced PC12 cells injury

PubMed Central

Bakhtiari, Elham; Hosseini, Azar; Mousavi, Seyed Hadi

2015-01-01

Objectives: Findings natural products with antioxidant and antiapoptotic properties has been one of the interesting challenges in the search for the treatment of neurodegenerative diseases including ischemic stroke. Serum/glucose deprivation (SGD) has been used as a model for the understanding of the molecular mechanisms of neuronal damage during ischemia in vitro and for the expansion of neuroprotective drugs against ischemia-induced brain injury. Recent studies showed that Hibiscus sabdariffa exert pharmacological actions such as potent antioxidant. Therefore, in this study we investigated the protective effect of extract of H. sabdariffa against SGD-induced PC12 cells injury. Materials and Methods: Cells were pretreated with different concentrations of H. sabdariffa extract (HSE) for 2 hr, and then exposed to SGD condition for 6, 12 and 18 hr. Results: SGD caused a major reduction in cell viability after 6, 12, and 18 hr as compared with control cells (p< 0.001). Pretreatment with HSE (30-500 𝜇g/mL) significantly increased cell viability following SGD insult for 6, 12 and 18 hr. A significant increase in cell apoptosis was seen in cells under SGD condition after 12hr as compared with control cells (p< 0.001). Pretreatment with HSE significantly decreased cell apoptosis subsequent SGD conditionafter12hr at concentration of 60, 125 and 250. Conclusion: These data showed that HSE had a protective property under SGD condition in PC12 cells, suggesting that H. sabdariffa has the potential to be used as a new therapeutic approach for neurodegenerative disorders. PMID:26101756

First-principles study of SnS electronic properties using LDA, PBE and HSE06 functionals

NASA Astrophysics Data System (ADS)

Ibragimova, R.; Ganchenkova, M.; Karazhanov, S.; Marstein, E. S.

2018-03-01

Recently, tin sulphide (SnS) has emerged as a promising alternative to conventional CIGS and CZTC for use in solar cells, possessing such properties as non-toxicity, low cost and production stability. SnS has a high theoretically predicted efficiency above 20%, but the experimentally achieved efficiency so far is as low as 4.36%. The reason for the low achieved efficiency is unclear. One of the powerful tools to get deeper insights about the nature of the problem is first-principles calculation approaches. That is why SnS has become an attractive subject for first-principles calculations recently. Previously calculated data, however, show a widespread of such fundamental value as the bandgap varying from 0.26 to 1.26 eV. In order to understand a reason for that, in this work, we concentrate on a systematic study of calculation parameters effects on the resulting electronic structure, with the particular attention paid to the influence of the exchange-correlation functional chosen for calculations. Several exchange-correlation functionals (LDA, PBE and HSE06) were considered. The systematic analysis has shown that the bandgap variation can result from a tensile/compressive hydrostatic pressure introduced by non-equilibrium lattice parameters used for the calculations. The study of the applicability of three functionals has shown that HSE06 gives the best match to both experimentally obtained bandgap and the XPS valence band spectra. LDA underestimates the bandgap but qualitatively reproduces experimentally measured valence DOS similar to that of HSE06 in contrast to PBE. PBE underestimates the bandgap and does not match to the measured XPS spectra.

Normocellular CSF in herpes simplex encephalitis.

PubMed

Saraya, Abhinbhen W; Wacharapluesadee, Supaporn; Petcharat, Sininat; Sittidetboripat, Nuntaporn; Ghai, Siriporn; Wilde, Henry; Hemachudha, Thiravat

2016-02-15

Herpes simplex virus (HSV) is the most common cause of sporadic encephalitis worldwide. The high mortality rate (70-80 %) of herpes simplex encephalitis (HSE) can be reduced to 20-30 % by antiviral therapy. However, normocellular CSF can lure physicians to look for non-infectious causes, resulting in delayed treatment. This study aimed to investigate, characterize and differentiate HSE patients, with normocellular and pleocytosis CSF, according to neuroimaging patterns, underlying disease, CSF viral load and clinical outcome. Patients with proven (by PCR positive CSF) or presumed viral infections of the CNS admitted to King Chulalongkorn Memorial Hospital between January 2002 and 2011 were analyzed. HSV was detected in the CSF of 43 patients but only 23 patients had encephalitis. Among these 23 patients, 6 cases (26.1 %) had normal CSF WBC (<5 cells/mm(3)). One patient in this normocellular CSF group had HIV infection. Although this patient had low CD4 counts (<200 cells/mm(3)), the peripheral WBC counts showed only mild leukopenia. The CSF HSV viral load in the pleocytosis group was higher than the normocellular group, with an average of 12,200 vs 3027 copies/ml respectively. There was no correlation between the viral load and the clinical outcome. With respect to neuroimaging, 4 (66.7 %) patients in the normocellular group had unremarkable/non-specific results. Normocellular CSF in HSE is not rare, and can be seen in normal as well as immunocompromised hosts. Clinicians should not exclude CNS infection, especially HSE, merely based on the absence of CSF pleocytosis and/or unremarkable neuroimaging study.

A review of the use of health examination data from the Health Survey for England in government policy development and implementation.

PubMed

Oyebode, Oyinlola; Mindell, Jennifer S

2014-01-01

Information is needed at all stages of the policy making process. The Health Survey for England (HSE) is an annual cross-sectional health examination survey of the non-institutionalised general population in England. It was originally set up to inform national policy making and monitoring by the Department of Health. This paper examines how the nurse collected physical and biological measurement data from the HSE have been essential or useful for identification of a health issue amenable to policy intervention; initiation, development or implementation of a strategy; choice and monitoring of targets; or assessment and evaluation of policies. Specific examples of use of HSE data were identified through interviews with senior members of staff at the Department of Health and the Health and Social Care Information Centre. Policy documents mentioned by interviewees were retrieved for review, and reference lists of associated policy documents checked. Systematic searches of Chief Medical Officer Reports, Government 'Command Papers', and clinical guidance documents were also undertaken. HSE examination data have been used at all stages of the policy making process. Data have been used to identify an issue amenable to policy-intervention (e.g. quantifying prevalence of undiagnosed chronic kidney disease), in strategy development (in models to inform chronic respiratory disease policy), for target setting and monitoring (the 1992 blood pressure target) and in evaluation of health policy (the effect of the smoking ban on second hand smoke exposure). A health examination survey is a useful part of a national health information system.

A review of the use of health examination data from the Health Survey for England in government policy development and implementation

PubMed Central

2014-01-01

Background Information is needed at all stages of the policy making process. The Health Survey for England (HSE) is an annual cross-sectional health examination survey of the non-institutionalised general population in England. It was originally set up to inform national policy making and monitoring by the Department of Health. This paper examines how the nurse collected physical and biological measurement data from the HSE have been essential or useful for identification of a health issue amenable to policy intervention; initiation, development or implementation of a strategy; choice and monitoring of targets; or assessment and evaluation of policies. Methods Specific examples of use of HSE data were identified through interviews with senior members of staff at the Department of Health and the Health and Social Care Information Centre. Policy documents mentioned by interviewees were retrieved for review, and reference lists of associated policy documents checked. Systematic searches of Chief Medical Officer Reports, Government ‘Command Papers’, and clinical guidance documents were also undertaken. Results HSE examination data have been used at all stages of the policy making process. Data have been used to identify an issue amenable to policy-intervention (e.g. quantifying prevalence of undiagnosed chronic kidney disease), in strategy development (in models to inform chronic respiratory disease policy), for target setting and monitoring (the 1992 blood pressure target) and in evaluation of health policy (the effect of the smoking ban on second hand smoke exposure). Conclusions A health examination survey is a useful part of a national health information system. PMID:25114791

Homeostatic Scaling of Excitability in Recurrent Neural Networks

PubMed Central

Remme, Michiel W. H.; Wadman, Wytse J.

2012-01-01

Neurons adjust their intrinsic excitability when experiencing a persistent change in synaptic drive. This process can prevent neural activity from moving into either a quiescent state or a saturated state in the face of ongoing plasticity, and is thought to promote stability of the network in which neurons reside. However, most neurons are embedded in recurrent networks, which require a delicate balance between excitation and inhibition to maintain network stability. This balance could be disrupted when neurons independently adjust their intrinsic excitability. Here, we study the functioning of activity-dependent homeostatic scaling of intrinsic excitability (HSE) in a recurrent neural network. Using both simulations of a recurrent network consisting of excitatory and inhibitory neurons that implement HSE, and a mean-field description of adapting excitatory and inhibitory populations, we show that the stability of such adapting networks critically depends on the relationship between the adaptation time scales of both neuron populations. In a stable adapting network, HSE can keep all neurons functioning within their dynamic range, while the network is undergoing several (patho)physiologically relevant types of plasticity, such as persistent changes in external drive, changes in connection strengths, or the loss of inhibitory cells from the network. However, HSE cannot prevent the unstable network dynamics that result when, due to such plasticity, recurrent excitation in the network becomes too strong compared to feedback inhibition. This suggests that keeping a neural network in a stable and functional state requires the coordination of distinct homeostatic mechanisms that operate not only by adjusting neural excitability, but also by controlling network connectivity. PMID:22570604

Characterization of a Human Skin Equivalent Model to Study the Effects of Ultraviolet B Radiation on Keratinocytes

PubMed Central

Van Lonkhuyzen, Derek R.; Dawson, Rebecca A.; Kimlin, Michael G.; Upton, Zee

2014-01-01

The incidences of skin cancers resulting from chronic ultraviolet radiation (UVR) exposure are on the incline in both Australia and globally. Hence, the cellular and molecular pathways that are associated with UVR-induced photocarcinogenesis need to be urgently elucidated, in order to develop more robust preventative and treatment strategies against skin cancers. In vitro investigations into the effects of UVR (in particular, the highly mutagenic UVB wavelength) have, to date, mainly involved the use of cell culture and animal models. However, these models possess biological disparities to native skin, which, to some extent, have limited their relevance to the in vivo situation. To address this, we characterized a three-dimensional, tissue-engineered human skin equivalent (HSE) model (consisting of primary human keratinocytes cultured on a dermal-derived scaffold) as a representation of a more physiologically relevant platform to study keratinocyte responses to UVB. Significantly, we demonstrate that this model retains several important epidermal properties of native skin. Moreover, UVB irradiation of the HSE constructs was shown to induce key markers of photodamage in the HSE keratinocytes, including the formation of cyclobutane pyrimidine dimers, the activation of apoptotic pathways, the accumulation of p53, and the secretion of inflammatory cytokines. Importantly, we also demonstrate that the UVB-exposed HSE constructs retain the capacity for epidermal repair and regeneration after photodamage. Together, our results demonstrate the potential of this skin equivalent model as a tool to study various aspects of the acute responses of human keratinocytes to UVB radiation damage. PMID:24219750

Geochemical and Re-Os isotope constraints on the origin and age of the Songshugou peridotite massif in the Qinling orogen, central China

NASA Astrophysics Data System (ADS)

Nie, Hu; Yang, Jianzhou; Zhou, Guangyan; Liu, Chuanzhou; Zheng, Jianping; Zhang, Wen-Xiang; Zhao, Yu-Jie; Wang, Hao; Wu, Yuanbao

2017-11-01

The Songshugou peridotite massif in the Qinling orogenic belt is one of the largest orogenic spinel peridotite bodies in central China, but its origin remains controversial and its age is poorly constrained. We have carried out an integrated study of major and trace element composition, mineral chemistry, platinum group elements (PGE), as well as Re-Os isotope systematics of 1 harzburgite and 12 dunites from the Songshugou peridotite massif. These samples contain high Mg# olivine (90.0-91.3) and Cr# spinel (83.4-96.0). The harzburgite and dunites are characterized by relatively low whole-rock Al2O3 (0.32-0.60 wt.%), CaO (0.26-1.57 wt.%), and Na2O (0.07-0.12 wt.%) concentrations. The studied samples have very low concentrations of middle and heavy rare earth elements and exhibit enrichments in iridium-group platinum-group elements (IPGE) relative to palladium-group PGE. The Songshugou peridotites exhibit variable enrichments of light rare earth elements, large ion lithophile elements, Re, Zr, and Hf, which resulted from reactions with melt after their isolation from the convecting mantle. Combined with previous results, our data suggest that the Songshugou peridotites are highly refractory mantle residues derived from a forearc mantle wedge. 187Os/188Os values of the studied samples vary from 0.12073 to 0.12390, and 187Re/188Os ratios are 0.005-0.081. The average Re-Os model ages (TMA) and maximum Re depletion model age (TRD) of the Songshugou peridotites are ca. 1.2-1.1 Ga, suggesting a tectonic affinity to the South China Block and that the peridotites formed during the assembly of the Rodinia supercontinent. The Songshugou peridotites were sourced from a mantle wedge above a subduction zone, and finally incorporated into the underlying continental lithosphere by exhumation.

Diagnosis and treatment of viral encephalitis

PubMed Central

Chaudhuri, A; Kennedy, P

2002-01-01

Acute encephalitis constitutes a medical emergency. In most cases, the presence of focal neurological signs and focal seizures will distinguish encephalitis from encephalopathy. Acute disseminated encephalomyelitis is a non-infective inflammatory encephalitis that may require to be treated with steroids. Acute infective encephalitis is usually viral. Herpes simplex encephalitis (HSE) is the commonest sporadic acute viral encephalitis in the Western world. Magnetic resonance imaging of brain is the investigation of choice in HSE and the diagnosis may be confirmed by the polymerase chain reaction test for the virus in the cerebrospinal fluid. In this article, we review the diagnosis, investigations, and management of acute encephalitis. With few exceptions (for example, aciclovir for HSE), no specific therapy is available for most forms of viral encephalitis. Mortality and morbidity may be high and long term sequelae are known among survivors. The emergence of unusual forms of zoonotic encephalitis has posed an important public health problem. Vaccination and vector control measures are useful preventive strategies in certain arboviral and zoonotic encephalitis. However, we need better antiviral therapy to meet the challenge of acute viral encephalitis more effectively. PMID:12415078

Role of non-local exchange in the electronic structure of correlated oxides

NASA Astrophysics Data System (ADS)

Iori, Federico; Gatti, Matteo; Rubio Secades, Angel

Transition-metal oxides (TMO) with partially filled d or f shells are a prototype of correlated materials. They exhibit very interesting properties, like metal-insulator phase transitions (MIT). In this work we consider several TMO insulators in which Kohn-Sham LDA band structures are metallic: VO2, V2O3, Ti2O3, LaTiO3 and YTiO3. In the past, this failure of LDA has been explained in terms of its inadequacy to capture the strong interactions taking place between correlated electrons. In the spirit of the Hubbard model, possible corrections to improve onsite correlation are the LDA +U and LDA +DMFT approaches. Here we make use of the HSE06 hybrid functional. We show that, without invoking strong-correlation effects, the contribution of the non-local Fock exchange is essential to correct the LDA results, by curing its delocalization error. In fact, HSE06 provides insulating band structures and correctly describes the MIT in all the considered compounds. We further discuss the advantages and the limitations of the HSE06 hybrid functional in correlated TMO

Effect of Spin-Orbit Coupling on the Actinide Dioxides AnO2 (An=Th, Pa, U, Np, Pu, and Am): A Screened Hybrid Density Functional Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wen, Xiaodong; Martin, Richard L.; Roy, Lindsay E.

2012-10-21

We present a systematic comparison of the lattice structures, electronic density of states, and band gaps of actinide dioxides, AnO₂ (An=Th, Pa, U, Np, Pu, and Am) predicted by the Heyd-Scuseria-Ernzerhof screened hybrid density functional (HSE) with the self-consistent inclusion of spin-orbit coupling(SOC). The computed HSE lattice constants and band gaps of AnO₂ are in consistently good agreement with the available experimental data across the series, and differ little from earlier HSE results without SOC. ThO₂ is a simple band insulator (f⁰), while PaO₂, UO₂, and NpO₂ are predicted to be Mott insulators. The remainders (PuO₂ and AmO₂) show considerablemore » O2p/An5f mixing and are classified as charge-transfer insulators. We also compare our results for UO₂, NpO₂, and PuO₂with the PBE+U, self interaction correction (SIC), and dynamic mean-field theory (DMFT) many-body approximations.« less

[Implementation and validation in the Italian context of the HSE management standards: a contribution to provide a practical model for the assessment of work-related stress].

PubMed

Iavicoli, S; Natali, E; Rondinone, B M; Castaldi, T; Persechino, B

2010-01-01

Over the last years, stress has been recognized as a potential work-related risk factor. Unfortunately, work-related stress is a very delicate subject, especially because it is difficult to assess it objectively and in broadly acceptable terms. In fact, work-related stress is a subjective personal response to a specific work environment, ad is of a multifactorial origin. In order to provide a practical tool for the assessment of work-related stress, the authors carried out a thorough benchmarking analysis of the various models to manage work stress problems adopted by EU countries. As a result, the authors have chosen to apply and implement the Health and Safety Executive (HSE) Management Standards approach in the Italian context. In compliance with the European Framework Agreement signed on October 8, 2004, HSE Management Standards ask for the coordinated and integrated involvement of workers and safety personnel and represent a valid assessment approach based on principles widely acknowledged in the scientific literature.

Systematic study of the effect of HSE functional internal parameters on the electronic structure and band gap of a representative set of metal oxides.

PubMed

Viñes, Francesc; Lamiel-García, Oriol; Chul Ko, Kyoung; Yong Lee, Jin; Illas, Francesc

2017-04-30

The effect of the amount of Hartree-Fock mixing parameter (α) and of the screening parameter (w) defining the range separated HSE type hybrid functional is systematically studied for a series of seven metal oxides: TiO 2 , ZrO 2 , CuO 2 , ZnO, MgO, SnO 2 , and SrTiO 3 . First, reliable band gap values were determined by comparing the optimal α reproducing the experiment with the inverse of the experimental dielectric constant. Then, the effect of the w in the HSE functional on the calculated band gap was explored in detail. Results evidence the existence of a virtually infinite number of combinations of the two parameters which are able to reproduce the experimental band gap, without a unique pair able to describe the full studied set of materials. Nevertheless, the results point out the possibility of describing the electronic structure of these materials through a functional including a screened HF exchange and an appropriate correlation contribution. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Characterization of carotenoid hydroxylase gene promoter in Haematococcus pluvialis.

PubMed

Meng, C X; Wei, W; Su, Z- L; Qin, S

2006-10-01

Astaxanthin, a high-value ketocarotenoid is mainly used in fish aquaculture. It also has potential in human health due to its higher antioxidant capacity than beta-carotene and vitamin E. The unicellular green alga Haematococcus pluvialis is known to accumulate astaxanthin in response to environmental stresses, such as high light intensity and salt stress. Carotenoid hydroxylase plays a key role in astaxanthin biosynthesis in H. pluvialis. In this paper, we report the characterization of a promoter-like region (-378 to -22 bp) of carotenoid hydroxylase gene by cloning, sequence analysis and functional verification of its 919 bp 5'-flanking region in H. pluvialis. The 5'-flanking region was characterized using micro-particle bombardment method and transient expression of LacZ reporter gene. Results of sequence analysis showed that the 5'-flanking region might have putative cis-acting elements, such as ABA (abscisic acid)-responsive element (ABRE), C-repeat/dehydration responsive element (C-repeat/DRE), ethylene-responsive element (ERE), heat-shock element (HSE), wound-responsive element (WUN-motif), gibberellin-responsive element (P-box), MYB-binding site (MBS) etc., except for typical TATA and CCAAT boxes. Results of 5' deletions construct and beta-galactosidase assays revealed that a highest promoter-like region might exist from -378 to -22 bp and some negative regulatory elements might lie in the region from -919 to -378 bp. Results of site-directed mutagenesis of a putative C-repeat/DRE and an ABRE-like motif in the promoter-like region (-378 to -22 bp) indicated that the putative C-repeat/DRE and ABRE-like motif might be important for expression of carotenoid hydroxylase gene.

An artificial HSE promoter for efficient and selective detection of heat shock pathway activity.

PubMed

Ortner, Viktoria; Ludwig, Alfred; Riegel, Elisabeth; Dunzinger, Sarah; Czerny, Thomas

2015-03-01

Detection of cellular stress is of major importance for the survival of cells. During evolution, a network of stress pathways developed, with the heat shock (HS) response playing a major role. The key transcription factor mediating HS signalling activity in mammalian cells is the HS factor HSF1. When activated it binds to the heat shock elements (HSE) in the promoters of target genes like heat shock protein (HSP) genes. They are induced by HSF1 but in addition they integrate multiple signals from different stress pathways. Here, we developed an artificial promoter consisting only of HSEs and therefore selectively reacting to HSF-mediated pathway activation. The promoter is highly inducible but has an extreme low basal level. Direct comparison with the HSPA1A promoter activity indicates that heat-dependent expression can be fully recapitulated by isolated HSEs in human cells. Using this sensitive reporter, we measured the HS response for different temperatures and exposure times. In particular, long heat induction times of 1 or 2 h were compared with short heat durations down to 1 min, conditions typical for burn injuries. We found similar responses to both long and short heat durations but at completely different temperatures. Exposure times of 2 h result in pathway activation at 41 to 44 °C, whereas heat pulses of 1 min lead to a maximum HS response between 47 and 50 °C. The results suggest that the HS response is initiated by a combination of temperature and exposure time but not by a certain threshold temperature.

The ruthenium isotopic composition of the oceanic mantle

NASA Astrophysics Data System (ADS)

Bermingham, K. R.; Walker, R. J.

2017-09-01

The approximately chondritic relative, and comparatively high absolute mantle abundances of the highly siderophile elements (HSE), suggest that their concentrations in the bulk silicate Earth were primarily established during a final ∼0.5 to 1% of ;late accretion; to the mantle, following the cessation of core segregation. Consequently, the isotopic composition of the HSE Ru in the mantle reflects an amalgamation of the isotopic compositions of late accretionary contributions to the silicate portion of the Earth. Among cosmochemical materials, Ru is characterized by considerable mass-independent isotopic variability, making it a powerful genetic tracer of Earth's late accretionary building blocks. To define the Ru isotopic composition of the oceanic mantle, the largest portion of the accessible mantle, we report Ru isotopic data for materials from one Archean and seven Phanerozoic oceanic mantle domains. A sample from a continental lithospheric mantle domain is also examined. All samples have identical Ru isotopic compositions, within analytical uncertainties, indicating that Ru isotopes are well mixed in the oceanic mantle, defining a μ100Ru value of 1.2 ± 7.2 (2SD). The only known meteorites with the same Ru isotopic composition are enstatite chondrites and, when corrected for the effects of cosmic ray exposure, members of the Main Group and sLL subgroup of the IAB iron meteorite complex which have a collective CRE corrected μ100Ru value of 0.9 ± 3.0. This suggests that materials from the region(s) of the solar nebula sampled by these meteorites likely contributed the dominant portion of late accreted materials to Earth's mantle.

Stochastic late accretion to Earth, the Moon, and Mars.

PubMed

Bottke, William F; Walker, Richard J; Day, James M D; Nesvorny, David; Elkins-Tanton, Linda

2010-12-10

Core formation should have stripped the terrestrial, lunar, and martian mantles of highly siderophile elements (HSEs). Instead, each world has disparate, yet elevated HSE abundances. Late accretion may offer a solution, provided that ≥0.5% Earth masses of broadly chondritic planetesimals reach Earth's mantle and that ~10 and ~1200 times less mass goes to Mars and the Moon, respectively. We show that leftover planetesimal populations dominated by massive projectiles can explain these additions, with our inferred size distribution matching those derived from the inner asteroid belt, ancient martian impact basins, and planetary accretion models. The largest late terrestrial impactors, at 2500 to 3000 kilometers in diameter, potentially modified Earth's obliquity by ~10°, whereas those for the Moon, at ~250 to 300 kilometers, may have delivered water to its mantle.

Experimental Determination of Spinel/Melt, Olivine/Melt, and Pyroxene/Melt Partition Coefficients for Re, Ru, Pd, Au, and Pt

NASA Technical Reports Server (NTRS)

Righter, K.; Campbell, A. J.; Humayun, M.

2003-01-01

Experimental studies have identified spinels as important hosts phases for many of the highly siderophile elements (HSE). Yet experimental studies involving chromite or Cr-rich spinel have been lacking. Experimental studies of partitioning of HSEs between silicate, oxides and silicate melt are plagued by low solubilities and the presence of small metallic nuggets at oxygen fugacities relevant to magmas, which interfere with analysis of the phases of interest. We have circumvented these problems in two ways: 1) performing experiments at oxidized conditions, which are still relevant to natural systems but in which nuggets are not observed, and 2) analysis of run products with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), allowing a combination of high sensitivity and good spatial resolution.

Constraints on the coupled thermal evolution of the Earth's core and mantle, the age of the inner core, and the origin of the 186Os/188Os “core signal” in plume-derived lavas

NASA Astrophysics Data System (ADS)

Lassiter, J. C.

2006-10-01

The possibility that some mantle plumes may carry a geochemical signature of core/mantle interaction has rightly generated considerable interest and attention in recent years. Correlated 186Os- 187Os enrichments in some plume-derived lavas (Hawaii, Gorgona, Kostomuksha) have been interpreted as deriving from an outer core with elevated Pt/Os and Re/Os ratios due to the solidification of the Earth's inner core (c.f., [A.D. Brandon, R.J. Walker, The debate over core-mantle interaction, Earth Planet. Sci. Lett. 232 (2005) 211-225.] and references therein). Conclusive identification of a "core signal" in plume-derived lavas would profoundly influence our understanding of mantle convection and evolution. This paper reevaluates the Os-isotope evidence for core/mantle interaction by examining other geochemical constraints on core/mantle interaction, geophysical constraints on the thermal evolution of the outer core, and geochemical and cosmochemical constraints on the abundance of heat-producing elements in the core. Additional study of metal/silicate and sulfide/silicate partitioning of K, Pb, and other trace elements is needed to more tightly constrain the likely starting composition of the Earth's core. However, available data suggest that the observed 186Os enrichments in Hawaiian and other plume-derived lavas are unlikely to derive from core/mantle interaction. 1) Core/mantle interaction sufficient to produce the observed 186Os enrichments would likely have significant effects on other tracers such as Pb- and W-isotopes that are not observed. 2) Significant partitioning of K or other heat-producing elements into the core would produce a "core depletion" pattern in the Silicate Earth very different from that observed. 3) In the absence of heat-producing elements in the core, core/mantle heat flow of ˜ 6-15 TW estimated from several independent geophysical constraints suggests an inner core age (< ˜ 2.5 Ga) too young for the outer core to have developed a significant 186Os enrichment. Core/mantle thermal and chemical interaction remains an important problem that warrants future research. However, Os-isotopes may have only limited utility in this area due to the relatively young age of the Earth's inner core.

Au36(SePh)24 nanomolecules: synthesis, optical spectroscopy and theoretical analysis.

PubMed

Rambukwella, Milan; Chang, Le; Ravishanker, Anish; Fortunelli, Alessandro; Stener, Mauro; Dass, Amala

2018-05-16

Here, we report the synthesis of selenophenol (HSePh) protected Au36(SePh)24 nanomolecules via a ligand-exchange reaction of 4-tert-butylbenzenethiol (HSPh-tBu) protected Au36(SPh-tBu)24 with selenophenol, and its spectroscopic and theoretical analysis. Matrix assisted laser desorption ionization (MALDI) mass spectrometry, electrospray ionization (ESI) mass spectrometry and optical characterization confirm that the composition of the as synthesized product is predominantly Au36(SePh)24 nanomolecules. Size exclusion chromatography (SEC) was employed to isolate the Au36(SePh)24 and temperature dependent optical absorption studies and theoretical analysis were performed. Theoretically, an Independent Component Maps of Oscillator Strength (ICM-OS) analysis of simulated spectra shows that the enhancement in absorption intensity in Au36(SePh)24 with respect to Au36(SPh)24 can be ascribed to the absence of interference and/or increased long-range coupling between interband metal core and ligand excitations. This work demonstrates and helps to understand the effect of Au-Se bridging on the properties of gold nanomolecules.

Characterization of Transcription Factor Gene OsDRAP1 Conferring Drought Tolerance in Rice

PubMed Central

Huang, Liyu; Wang, Yinxiao; Wang, Wensheng; Zhao, Xiuqin; Qin, Qiao; Sun, Fan; Hu, Fengyi; Zhao, Yan; Li, Zichao; Fu, Binying; Li, Zhikang

2018-01-01

HIGHLIGHTS Overexpressing and RNA interfering OsDRAP1 transgenic rice plants exhibited significantly improved and reduced drought tolerance, but accompanied with negative effects on development and yield. The dehydration responsive element binding (DREBs) genes are important transcription factors which play a crucial role in plant abiotic stress tolerances. In this study, we functionally characterized a DREB2-like gene, OsDRAP1 conferring drought tolerance (DT) in rice. OsDRAP1, containing many cis-elements in its promoter region, was expressed in all organs (mainly expressed in vascular tissues) of rice, and induced by a variety of environmental stresses and plant hormones. Overexpressing OsDRAP1 transgenic plants exhibited significantly improved DT; while OsDRAP1 RNA interfering plants exhibited significantly reduced DT which also accompanied with significant negative effects on development and yield. Overexpression of OsDRAP1 has a positive impact on maintaining water balance, redox homeostasis and vascular development in transgenic rice plants under drought stress. OsDRAP1 interacted with many genes/proteins and could activate many downstream DT related genes, including important transcription factors such as OsCBSX3 to response drought stress, indicating the OsDRAP1-mediated pathways for DT involve complex genes networks. All these results provide a basis for further complete understanding of the OsDRAP1 mediated gene networks and their related phenotypic effects. PMID:29449862

Representativeness and optimal use of body mass index (BMI) in the UK Clinical Practice Research Datalink (CPRD)

PubMed Central

Bhaskaran, Krishnan; Forbes, Harriet J; Douglas, Ian; Leon, David A; Smeeth, Liam

2013-01-01

Objectives To assess the completeness and representativeness of body mass index (BMI) data in the Clinical Practice Research Datalink (CPRD), and determine an optimal strategy for their use. Design Descriptive study. Setting Electronic healthcare records from primary care. Participants A million patient random sample from the UK CPRD primary care database, aged ≥16 years. Primary and secondary outcome measures BMI completeness in CPRD was evaluated by age, sex and calendar period. CPRD-based summary BMI statistics for each calendar year (2003–2010) were age-standardised and sex-standardised and compared with equivalent statistics from the Health Survey for England (HSE). Results BMI completeness increased over calendar time from 37% in 1990–1994 to 77% in 2005–2011, was higher among females and increased with age. When BMI at specific time points was assigned based on the most recent record, calendar–year-specific mean BMI statistics underestimated equivalent HSE statistics by 0.75–1.1 kg/m2. Restriction to those with a recent (≤3 years) BMI resulted in mean BMI estimates closer to HSE (≤0.28 kg/m2 underestimation), but excluded up to 47% of patients. An alternative strategy of imputing up-to-date BMI based on modelled changes in BMI over time since the last available record also led to mean BMI estimates that were close to HSE (≤0.37 kg/m2 underestimation). Conclusions Completeness of BMI in CPRD increased over time and varied by age and sex. At a given point in time, a large proportion of the most recent BMIs are unlikely to reflect current BMI; consequent BMI misclassification might be reduced by employing model-based imputation of current BMI. PMID:24038008

[Yogurt consumption and reduced risk of overweight and obesity in adults].

PubMed

Martinchik, A N; Baturin, A K; Peskova, E V; Keshabyants, E E; Mikhaylov, N A

2016-01-01

Fermented dairy products comprise a large food group in Russia and are an important source of dietary nutrients like protein, calcium, fat. Obesity is a rising public health issue in Russia. Observing the role of fermented dairy in the maintenance of healthy weights is important. Current study objective was to explore the association between obesity/overweight prevalence and yogurt consumption in Russian adults. Data from RLMS-HSE 1994-2012 was used. Primary materials are available on http://www.cpc.unc.edu/projects/rlms-hse, http://www. hse.ru/org/hse/rlms. Data collected included dietary intake by single 24h recalls and anthropometric measures for 72.400 adults (≥ 19 y.o.). Logistic regression models were used to explore the relationships between yogurt consumption and obesity prevalence (BMI > 30.0 compared with. 18.5-25.0), controlling for age and gender. Daily average intake (g/day) of yogurt significantly increased from 1994 to 2012. Yogurt consumption decreased over 40 y.o. in both gender. Women yogurt consumption is inversely correlated with the magnitude of the BMI: the consumption of yogurt in women with normal BMI values (> 18.5-25.0) was significantly higher than in women who are overweight and/or obese (BMI > 25.0; or > 30.0). The mean values of BMI in women who ate yogurt, were significantly lower than in women not consuming yogurt. In men, the relationship between consumption of yogurt and BMI is not revealed. Thus, among women, a significant inverse association was observed between yogurt consumption and obesity (OR 0.582, CI 95% 0.497, 0.680; p < 0.001). The observed association between yogurt intake and prevalence of obesity is dependent on gender: yogurt is associated with lower obesity prevalence only in women.

Potentially inappropriate prescribing in two populations with differing socio-economic profiles: a cross-sectional database study using the PROMPT criteria.

PubMed

Cooper, Janine A; Moriarty, Frank; Ryan, Cristín; Smith, Susan M; Bennett, Kathleen; Fahey, Tom; Wallace, Emma; Cahir, Caitriona; Williams, David; Teeling, Mary; Hughes, Carmel M

2016-05-01

The purpose of this study is to establish the prevalence of potentially inappropriate prescribing (PIP) in middle-aged adults (45-64 years) in two populations with differing socio-economic profiles, and to investigate factors associated with PIP, using the PROMPT (PRescribing Optimally in Middle-aged People's Treatments) criteria. A retrospective cross-sectional study was conducted using 2012 data from the Enhanced Prescribing Database (EPD), covering the full population in Northern Ireland and the Health Services Executive Primary Care Reimbursement Service (HSE-PCRS) database, covering the most socio-economically deprived third of the population in this age group in the Republic of Ireland. The prevalence for each PROMPT criterion and overall prevalence of PIP were calculated. Logistic regression was used to investigate the association between PIP and gender, age group and polypharmacy. This study included 441,925 patients from the EPD and 309,748 patients from the HSE-PCRS database. Polypharmacy was common in both datasets (46.7 % in the HSE-PCRS and 20.3 % in the EPD). The prevalence of PIP was 42.9 % (95%CI 42.7, 43.1) in the HSE-PCRS and 21.1 % (95%CI 21.0, 21.2) in the EPD. Age group, female gender and polypharmacy were significantly associated with PIP in both populations (p < 0.05) and polypharmacy had the strongest association. PIP is common amongst middle-aged people with the risk of PIP increasing with polypharmacy. Differences in the prevalence of polypharmacy and PIP between the two populations may relate to heterogeneity in healthcare services and different socio-economic profiles, with higher rates of multimorbidity and associated polypharmacy in more deprived groups.

Toxicology of hydrogen fluoride in relation to major accident hazards.

PubMed

Meldrum, M

1999-10-01

A major industrial accident involving the release of hydrogen fluoride has the potential to cause serious injury and possibly death in the surrounding human population. Given the potential for such serious and large-scale effects, there is a need for scientifically based risk assessments for determining appropriate on-site risk control measures, as well as for informing off-site emergency plans and land-use development decisions. Within Great Britain, the Health and Safety Executive (HSE) has the statutory responsibility for providing land-use planning advice in the vicinity of major accident hazard sites. The advice is based on quantified assessment of the individual risk of exposure to a specified amount of the toxic substance. Among other things this requires a consistent, reliable, and transparent understanding of the major hazard toxicology of the substance concerned. An assessment of the toxicology of hydrogen fluoride in relation to major accident hazards, based on conventional inhalation toxicity studies, was published by HSE in 1993. Recently, studies have been reported in which rats inhaled hydrogen fluoride via a mouthpiece attached to an endotracheal cannula. HSE has explored the use of this "mouth-breathing" rat model as a possible basis for human health risk assessment for hydrogen fluoride in the context of major accident hazards. A number of uncertainties in the use of this animal model have been identified that warrant caution in the use of this model for regulatory purposes. Overall, the results from the "mouth-breathing" rat model did not lead to a change in the HSE assessment of hydrogen fluoride, which remains based on experimental data obtained following "mainstream" toxicological practices. Copyright 1999 Academic Press.

International Environmental Evaluation for the Helical Screw Expander Generator Unit Projects in Cesano, Italy and Broadlands, New Zealand

DOE Office of Scientific and Technical Information (OSTI.GOV)

Webb, J.W.; Mezga, L.J.; Reed, A.W.

1981-08-01

The objectives of the Helical Screw Expander (HSE) Generator Program are (1) to accelerate the development of geothermal resources by introducing this advanced conversion technology, (2) to provide operating experience to prospective users of the equipment, and (3) to collect data on the performance and reliability of the equipment under various geothermal resource conditions. The participants hope to achieve these goals by testing a small-scale, transportable HSE generator at existing geothermal test facilities that produce fluids of different salinity, temperature and pressure conditions. This Environmental Evaluation has been prepared, using available information, to analyze the environmental consequences of testing themore » HSE generator. Its purpose is to support a decision on the need for a complete environmental review of the HSE program under the terms of Executive Order 121 14, ''Environmental Effects Abroad of Major federal Actions''. This Executive Order requires review of projects which involve the release of potentially toxic effluents that are strictly regulated in the United States, or which may have significant environmental effects on the global commons, on natural or ecological resources of international significance, or on the environment of non-participating countries. The final guidelines implementing the provisions of the Executive Order for DOE have been published. This evaluation deals with testing to be conducted at Cesano, Italy by the designated contractor of the Italian government, the Ente Narionale per l'Energia Ellectrica (ENEL), and at Broadlands, New Zealand by the Ministry of Works and Development of New Zealand. Testing at Cerro Prieto, Mexico has already been completed by the Comision Federal de Electricidad and is not evaluated in this report.« less

Experience of the nuclear reactors (environmental impact assessment for decommissioning) regulations 1999, as amended, in Great Britain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Sarah; Mattress, Elaine; Nettleton, Jo

2007-07-01

Available in abstract form only. Full text of publication follows: In Great Britain, the Nuclear Reactors (Environmental Impact Assessment for Decommissioning) Regulations 1999 as amended 2006 (EIADR) requires assessment of the potential environmental impacts of projects to decommission nuclear power stations and reactors. The Health and Safety Executive (HSE) is the competent authority for EIADR. The EIADR implement European Council Directive 85/337/EEC (the EIA Directive) as amended by Council Directive 97/11/EC and Council Directive 2003/35/EC the (Public Participation Directive). The purpose of the EIADR is to assess environmental effects of nuclear reactor decommissioning projects, involve the public through consultation, andmore » make the decision-making process open and transparent. Under the regulations, any licensee wishing to begin to decommission or dismantle a nuclear power station, or other civil nuclear reactor, must apply to HSE for consent to carry out the decommissioning project, undertake an environmental impact assessment and prepare an environmental statement that summarises the environmental effects of the project. HSE will consult on the environmental statement. So far under the EIADR there have been six consents granted for decommissioning projects for Magnox Power Stations. These stations have been required as a condition of consent to submit an Environmental Management Plan on an annual basis. This allows the project to be continually reviewed and assessed to ensure that the licensee can provide detail as agreed during the review of the environmental statement and that any changes to mitigation measures are detailed. This paper summarises the EIADR process, giving particular emphasis to public participation and the decision making process, and discusses HSE's experience of EIADR with reference to specific environmental issues raised by stakeholders and current developments. (authors)« less

Changes in gene expression and catalase activity in Oryza sativa L. under abiotic stress.

PubMed

Vighi, I L; Benitez, L C; do Amaral, M N; Auler, P A; Moraes, G P; Rodrigues, G S; da Maia, L C; Pinto, L S; Braga, E J B

2016-11-03

Different rice (Oryza sativa L.) genotypes were subjected to high salinity and low temperature (150 mM NaCl and 13°C, respectively) for 0, 6, 24, 48, or 72 h. We evaluated the simultaneous expression of the genes OsCATA, OsCATB, and OsCATC, correlated gene expression with enzyme activity, and verified the regulation of these genes through identification of cis-elements in the promoter region. The hydrogen peroxide content increased in a tolerant genotype and decreased in a sensitive genotype under both stress conditions. Lipid peroxidation increased in the tolerant genotype when exposed to cold, and in the sensitive genotype when exposed to high salinity. Catalase activity significantly increased in both genotypes when subjected to 13°C. In the tolerant genotype, OsCATA and OsCATB were the most responsive to high salinity and cold, while in the sensitive genotype, OsCATA and OsCATC responded positively to saline stress, as did OsCATA and OsCATB to low temperature. Cis-element analysis identified different regulatory sequences in the catalase promoter region of each genotype. The sensitive genotype maintained a better balance between hydrogen oxyacid levels, catalase activity, and lipid peroxidation under low temperature than the resistant genotype. OsCATA and OsCATB were the most responsive in the salt-tolerant genotype to cold, OsCATA and OsCATC were the most responsive to saline stress, and OsCATA and OsCATB were the most responsive to chilling stress in the sensitive genotype. There were positive correlations between catalase activity and OsCATB expression in the tolerant genotype under saline stress and in the sensitive genotype under cold stress.

Health and safety executive inspection of U.K. semiconductor manufacturers.

PubMed

Watterson, Andrew; LaDou, Joseph

2003-01-01

Europe plays a major role in the international semiconductor industry, but has conducted few studies of the occupational health of its workers. An exception is in the United Kingdom, where, in two small studies, the Health and Safety Executive (HSE) evaluated some health effects of semiconductor work. Neither of these studies, largely restricted to Scotland, produced definitive results, and both were misused by industry to assert that they demonstrated no adverse health effect on workers. The results of the studies prompted semiconductor industry inspections recently completed by the HSE that included chip manufacturers in Scotland and other U.K. areas. The results of these inspections are disappointing.

Warm Dense Matter Demonstrating Non-Drude Conductivity from Observations of Nonlinear Plasmon Damping

NASA Astrophysics Data System (ADS)

Witte, B. B. L.; Fletcher, L. B.; Galtier, E.; Gamboa, E.; Lee, H. J.; Zastrau, U.; Redmer, R.; Glenzer, S. H.; Sperling, P.

2017-06-01

We present simulations using finite-temperature density-functional-theory molecular dynamics to calculate the dynamic electrical conductivity in warm dense aluminum. The comparison between exchange-correlation functionals in the Perdew-Burke-Enzerhof and Heyd-Scuseria-Enzerhof (HSE) approximation indicates evident differences in the density of states and the dc conductivity. The HSE calculations show excellent agreement with experimental Linac Coherent Light Source x-ray plasmon scattering spectra revealing plasmon damping below the widely used random phase approximation. These findings demonstrate non-Drude-like behavior of the dynamic conductivity that needs to be taken into account to determine the optical properties of warm dense matter.

Herpes Simplex Type 2 Encephalitis After Craniotomy: Case Report and Literature Review.

PubMed

Berger, Assaf; Shahar, Tal; Margalit, Nevo

2016-04-01

Herpes simplex encephalitis (HSE) after neurosurgical procedures is extremely uncommon, and the few published case reports mainly described herpes simplex virus type 1 (HSV-1) as being culpable. We present a rare case of HSV-2 encephalitis after craniotomy and describe its pathophysiology and optimal management. A 70-year-old woman underwent an elective resection of a recurrent left sphenoid wing meningioma and clipping of a left middle cerebral artery aneurysm, the latter having been found incidentally. She returned to our department with clinical findings suggestive of meningitis 12 days after the operation. Her lack of response to empiric antibiotic treatment, taken together with the lymphocyte-predominant initial cerebrospinal fluid obtained by lumbar puncture and the electroencephalographic indications of encephalopathy, led to the suspicion of a diagnosis of HSE, which was later confirmed by a polymerase chain reaction test positive for HSV-2. The patient was then successfully treated with intravenous acyclovir for 2 weeks followed by another week of oral acyclovir treatment before being discharged. The present case stresses the importance of recognizing the relatively rare entity of HSE after craniotomy. Timely correct diagnosis will expedite the initiation of appropriate treatment. Copyright © 2016 Elsevier Inc. All rights reserved.

Re-assessment of offshore structures using the revised HSE fatigue guidance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stacey, A.; Sharp, J.V.

1995-12-31

The re-assessment of existing North Sea structures is an increasingly important issue as the age of platforms increases. Over 50 from a total of approximately 180 fixed installations in the UK sector are now over 15 years old. Fatigue damage has been the main reason for repairs to North Sea structures and the risk of this continues. The fatigue guidance of the Offshore Safety Division of the Health and Safety Executive (HSE) has recently been revised and published. Fundamental changes have been made to this guidance with several new recommendations including joint classification, basic design S-N curves for welded joints,more » the thickness effect, the effects of environment and the treatment of low and high stress ranges. To quantify the effects of the new guidance on the fatigue life assessment of offshore strictures, the HSE commissioned a study which included a deep water and a shallow water fixed steel structure and a twin-pontoon semi-submersible. These structures are typical of those operating in the North Sea. These were re-assessed with respect to fatigue lives and the results compared with predictions based on the 1990 guidance. The results and general conclusions are presented in this paper.« less

Metal ions induced heat shock protein response by elevating superoxide anion level in HeLa cells transformed by HSE-SEAP reporter gene.

PubMed

Yu, Zhanjiang; Yang, Xiaoda; Wang, Kui

2006-06-01

The aim of this work is to define the relationship between heat shock protein (HSP) and reactive oxygen species (ROS) in the cells exposed to different concentrations of metal ions, and to evaluate a new method for tracing the dynamic levels of cellular reactive oxygen species using a HSE-SEAP reporter gene. The expression of heat shock protein was measured using a secreted alkaline phosphatase (SEAP) reporter gene transformed into HeLa cell strain, the levels of superoxide anion (O(2)(-)) and hydrogen peroxide (H(2)O(2)) were determined by NBT reduction assay and DCFH staining flow cytometry (FCM), respectively. The experimental results demonstrated that the expression of heat shock protein induced by metal ions was linearly related to the cellular superoxide anion level before cytotoxic effects were observed, but not related to the cellular hydrogen peroxide level. The experimental results suggested that metal ions might induce heat shock protein by elevating cellular superoxide anion level, and thus the expression of heat shock protein indicated by the HSE-SEAP reporter gene can be an effective model for monitoring the dynamic level of superoxide anion and early metal-induced oxidative stress/cytotoxicity.

Genome-wide analysis identifies chickpea (Cicer arietinum) heat stress transcription factors (Hsfs) responsive to heat stress at the pod development stage.

PubMed

Chidambaranathan, Parameswaran; Jagannadham, Prasanth Tej Kumar; Satheesh, Viswanathan; Kohli, Deshika; Basavarajappa, Santosh Halasabala; Chellapilla, Bharadwaj; Kumar, Jitendra; Jain, Pradeep Kumar; Srinivasan, R

2018-05-01

The heat stress transcription factors (Hsfs) play a prominent role in thermotolerance and eliciting the heat stress response in plants. Identification and expression analysis of Hsfs gene family members in chickpea would provide valuable information on heat stress responsive Hsfs. A genome-wide analysis of Hsfs gene family resulted in the identification of 22 Hsf genes in chickpea in both desi and kabuli genome. Phylogenetic analysis distinctly separated 12 A, 9 B, and 1 C class Hsfs, respectively. An analysis of cis-regulatory elements in the upstream region of the genes identified many stress responsive elements such as heat stress elements (HSE), abscisic acid responsive element (ABRE) etc. In silico expression analysis showed nine and three Hsfs were also expressed in drought and salinity stresses, respectively. Q-PCR expression analysis of Hsfs under heat stress at pod development and at 15 days old seedling stage showed that CarHsfA2, A6, and B2 were significantly upregulated in both the stages of crop growth and other four Hsfs (CarHsfA2, A6a, A6c, B2a) showed early transcriptional upregulation for heat stress at seedling stage of chickpea. These subclasses of Hsfs identified in this study can be further evaluated as candidate genes in the characterization of heat stress response in chickpea.

Preliminary Study to Test the Feasibility of Sex Identification of Human (Homo sapiens) Bones Based on Differences in Elemental Profiles Determined by Handheld X-ray Fluorescence.

PubMed

Nganvongpanit, Korakot; Buddhachat, Kittisak; Brown, Janine L; Klinhom, Sarisa; Pitakarnnop, Tanita; Mahakkanukrauh, Pasuk

2016-09-01

Sex assignment of human remains is a crucial step in forensic anthropological studies. The aim of this study was to examine elemental differences between male and female bones using X-ray fluorescence (XRF) and determine if elemental profiling could be used for sex discrimination. Cranium, humerus, and os coxae of 60 skeletons (30 male, 30 female) from the Chiang Mai University Skeletal Collection were scanned by XRF and differences in elemental profiles between male and female bones determined using discriminant analysis. In the cranium, three elements (S, Ca, Pb) were significantly higher in males and five elements (Si, Mn, Fe, Zn, Ag) plus light elements (atomic number lower than 12) were higher in females. In humerus and os coxae, nine elements were significantly higher in male and one element was higher in female samples. The accuracy rate for sex estimation was 60, 63, and 61 % for cranium, humerus, and os coxae, respectively, and 67 % when data for all three bones were combined. We conclude that there are sex differences in bone elemental profiles; however, the accuracy of XRF analyses for discriminating between male and female samples was low compared to standard morphometric and molecular methods. XRF could be used on small samples that cannot be sexed by traditional morphological methods, but more work is needed to increase the power of this technique for gender assignment.

The mature anther-preferentially expressed genes are associated with pollen fertility, pollen germination and anther dehiscence in rice.

PubMed

Ling, Sheng; Chen, Caisheng; Wang, Yang; Sun, Xiaocong; Lu, Zhanhua; Ouyang, Yidan; Yao, Jialing

2015-02-19

The anthers and pollen grains are critical for male fertility and hybrid rice breeding. The development of rice mature anther and pollen consists of multiple continuous stages. However, molecular mechanisms regulating mature anther development were poorly understood. In this study, we have identified 291 mature anther-preferentially expressed genes (OsSTA) in rice based on Affymetrix microarray data. Gene Ontology (GO) analysis indicated that OsSTA genes mainly participated in metabolic and cellular processes that are likely important for rice anther and pollen development. The expression patterns of OsSTA genes were validated using real-time PCR and mRNA in situ hybridizations. Cis-element identification showed that most of the OsSTA genes had the cis-elements responsive to phytohormone regulation. Co-expression analysis of OsSTA genes showed that genes annotated with pectinesterase and calcium ion binding activities were rich in the network, suggesting that OsSTA genes could be involved in pollen germination and anther dehiscence. Furthermore, OsSTA RNAi transgenic lines showed male-sterility and pollen germination defects. The results suggested that OsSTA genes function in rice male fertility, pollen germination and anther dehiscence and established molecular regulating networks that lay the foundation for further functional studies.

Glutamine's protection against cellular injury is dependent on heat shock factor-1.

PubMed

Morrison, Angela L; Dinges, Martin; Singleton, Kristen D; Odoms, Kelli; Wong, Hector R; Wischmeyer, Paul E

2006-06-01

Glutamine (GLN) has been shown to protect cells, tissues, and whole organisms from stress and injury. Enhanced expression of heat shock protein (HSP) has been hypothesized to be responsible for this protection. To date, there are no clear mechanistic data confirming this relationship. This study tested the hypothesis that GLN-mediated activation of the HSP pathway via heat shock factor-1 (HSF-1) is responsible for cellular protection. Wild-type HSF-1 (HSF-1(+/+)) and knockout (HSF-1(-/-)) mouse fibroblasts were used in all experiments. Cells were treated with GLN concentrations ranging from 0 to 16 mM and exposed to heat stress injury in a concurrent treatment model. Cell viability was assayed with phenazine methosulfate plus tetrazolium salt, HSP-70, HSP-25, and nuclear HSF-1 expression via Western blot analysis, and HSF-1/heat shock element (HSE) binding via EMSA. GLN significantly attenuated heat-stress induced cell death in HSF-1(+/+) cells in a dose-dependent manner; however, the survival benefit of GLN was lost in HSF-1(-/-) cells. GLN led to a dose-dependent increase in HSP-70 and HSP-25 expression after heat stress. No inducible HSP expression was observed in HSF-1(-/-) cells. GLN increased unphosphorylated HSF-1 in the nucleus before heat stress. This was accompanied by a GLN-mediated increase in HSF-1/HSE binding and nuclear content of phosphorylated HSF-1 after heat stress. This is the first demonstration that GLN-mediated cellular protection after heat-stress injury is related to HSF-1 expression and cellular capacity to activate an HSP response. Furthermore, the mechanism of GLN-mediated protection against injury appears to involve an increase in nuclear HSF-1 content before stress and increased HSF-1 promoter binding and phosphorylation.

Ha-ras(val12) induces HSP70b transcription via the HSE/HSF1 system, but HSP70b expression is suppressed in Ha-ras(val12)-transformed cells.

PubMed

Stanhill, A; Levin, V; Hendel, A; Shachar, I; Kazanov, D; Arber, N; Kaminski, N; Engelberg, D

2006-03-09

Heat shock proteins (Hsps) are overexpressed in many tumors, but are downregulated in some tumors. To check for a direct effect of Ha-Ras(val12) on HSP70 transcription, we transiently expressed the oncoprotein in Rat1 fibroblasts and monitored its effect on HSP70b promoter-driven reporter gene. We show that expression of Ha-Ras(val12) induced this promoter. Promoter analysis via systematic deletions and point mutations revealed that Ha-Ras(val12) induces HSP70b transcription via heat shock elements (HSEs). Also, Ha-Ras(val12) induction of HSE-mediated transcription was dramatically reduced in HSF1-/- cells. Yet, residual effect of Ha-Ras(val12) that was still measured in HSF1-/- cells suggests that some of the Ha-Ras(val12) effect is Hsf1-independent. When HSF1-/- cells, stably expressing Ha-Ras(val12), were grown on soft agar only small colonies were formed suggesting a role for heat shock factor 1 (Hsf1) in Ha-Ras(val12)-mediated transformation. Although Ha-ras(Val12) seems to be an inducer of HSP70's expression, we found that in Ha-ras(Val12-)transformed fibroblasts expression of this gene is suppressed. This suppression is correlated with higher sensitivity of Ha-ras(val12)-transformed cells to heat shock. We suggest that Ha-ras(Val12) is involved in Hsf1 activation, thereby inducing the cellular protective response. Cells that repress this response are perhaps those that acquire the capability to further proliferate and become transformed clones.

Observations of non-linear plasmon damping in dense plasmas

NASA Astrophysics Data System (ADS)

Witte, B. B. L.; Sperling, P.; French, M.; Recoules, V.; Glenzer, S. H.; Redmer, R.

2018-05-01

We present simulations using finite-temperature density-functional-theory molecular-dynamics to calculate dynamic dielectric properties in warm dense aluminum. The comparison between exchange-correlation functionals in the Perdew, Burke, Ernzerhof approximation, Strongly Constrained and Appropriately Normed Semilocal Density Functional, and Heyd, Scuseria, Ernzerhof (HSE) approximation indicates evident differences in the electron transition energies, dc conductivity, and Lorenz number. The HSE calculations show excellent agreement with x-ray scattering data [Witte et al., Phys. Rev. Lett. 118, 225001 (2017)] as well as dc conductivity and absorption measurements. These findings demonstrate non-Drude behavior of the dynamic conductivity above the Cooper minimum that needs to be taken into account to determine optical properties in the warm dense matter regime.

A Cluster of Hepatitis A Viral Infection in HSE South.

PubMed

Ferris, H A; Dillon, A; O'Sullivan, M B

2017-06-09

Hepatitis A is an acute viral infection of the liver that produces clinical features ranging from asymptomatic infection to fulminant hepatitis 1 . The authors report a cluster of 5 serologically-confirmed cases of acute Hepatitis A Virus (HAV), all serum IgM positive for HAV Genotype 1A. This is on a background of only 2 other cases notified to HSE-South in 2016 to date, both travel related. There was a considerable delay in notification in two out of 5 cases. This case report highlights the importance of prompt notification of Hepatitis A, as timely notification would have facilitated prompt contact vaccination and might well have prevented illness in two subsequent household contacts.

Comparative Morphology of Sulfur Mustard Effects in the Hairless Guinea Pig and a Human Skin Equivalent

DTIC Science & Technology

1993-01-01

guinea pig model (HD-HGP). HSE samples were exposed to 10 micro l HD vapor for 8 min and harvested at selected times up to 24 h. Skin sites of HGP were exposed to the same vapor dose or to 2.0 micro l HD for 30 min and collected at 12 and 24 h. In both models, basal cells of the stratum germinativum were selectively affected. The HD-HSE study revealed that basal cell changes began 3 to 6 h following exposure. These early cellular included an acantholysis of some basal cells with widening of intercellular spaces, disruption of desmosomal attachments, nuclear pyknosis,

Protective Effect of Hibiscus Sabdariffa on Doxorubicin-induced Cytotoxicity in H9c2 Cardiomyoblast Cells

PubMed Central

Hosseini, Azar; Bakhtiari, Elham; Mousavi, Seyed Hadi

2017-01-01

Doxorubicin (DOX) is an effective anticancer drug. But its clinical application is limited, because DOX induces apoptosis in cardiomyocytes and it leads to permanent degenerative cardiomyopathy and heart failure. Recent trainings showed that Hibiscus sabdariffa exhibit pharmacological actions such as potent antioxidant. So, in this study we explored the protective effect of H. sabdariffa extract on doxorubicin-induced cytotoxicity in H9c2 cells. Cell viability was quantified by MTT assay. Apoptotic cells were determined using PI staining of DNA fragmentation by flowcytometry (sub-G1 peak). Cells were cultured with 5 μM DOX for 24 h to create the cell damage. H9c2 cells were pretreated with different concentrations (7.81-500 μg/mL) of H. sabdariffa extract (HSE) for 2 h before DOX treatment in all trials. Pretreatment with HSE increased cell viability at concentration of 31.25-500 μg/mL. Compared to control cells, apoptosis was induced in DOX treated cells after 24 h, (𝑃< 0.001). Pretreatment with HSE significantly decreased cell apoptosis after 24 hr at concentration of 31.25-250 μg/mL. Our results show that H. sabdariffa could exert the cardioprotective effects on DOX-induced toxicity partly by antiapoptotic activity. PMID:28979325

Protective Effect of Hibiscus Sabdariffa on Doxorubicin-induced Cytotoxicity in H9c2 Cardiomyoblast Cells.

PubMed

Hosseini, Azar; Bakhtiari, Elham; Mousavi, Seyed Hadi

2017-01-01

Doxorubicin (DOX) is an effective anticancer drug. But its clinical application is limited, because DOX induces apoptosis in cardiomyocytes and it leads to permanent degenerative cardiomyopathy and heart failure. Recent trainings showed that Hibiscus sabdariffa exhibit pharmacological actions such as potent antioxidant. So, in this study we explored the protective effect of H. sabdariffa extract on doxorubicin-induced cytotoxicity in H9c2 cells. Cell viability was quantified by MTT assay. Apoptotic cells were determined using PI staining of DNA fragmentation by flowcytometry (sub-G1 peak). Cells were cultured with 5 μM DOX for 24 h to create the cell damage. H9c2 cells were pretreated with different concentrations (7.81-500 μg/mL) of H. sabdariffa extract (HSE) for 2 h before DOX treatment in all trials. Pretreatment with HSE increased cell viability at concentration of 31.25-500 μg/mL. Compared to control cells, apoptosis was induced in DOX treated cells after 24 h, (< 0.001). Pretreatment with HSE significantly decreased cell apoptosis after 24 hr at concentration of 31.25-250 μg/mL. Our results show that H. sabdariffa could exert the cardioprotective effects on DOX-induced toxicity partly by antiapoptotic activity.

Managing Asbestos-Containing Materials in the Built Environment: Report of a Health and Safety Executive and Government Office for Science Workshop.

PubMed

Bowen, Jo; Davies, Laurie; Burdett, Garry John; Barber, Christopher Michael

2017-01-01

The duty to manage asbestos in non-domestic premises is described in the Control of Asbestos Regulations 2012. Health and Safety Executive (HSE) policy and guidance on asbestos in the built environment in Great Britain is that asbestos-containing materials (ACMs) that are in good condition and unlikely to be disturbed can be managed in place. Where ACMs are in poor condition or likely to be disturbed they should be repaired, encapsulated or, if necessary, removed. HSE and Government Office for Science hosted a stakeholder workshop to consider evidence on the management of ACMs in public buildings. Invitees attended from a range of backgrounds (including regulatory, government, academic, medical, public interest groups, and professional service providers). Participants considered the evidence, suggested nine evidence gap areas and ranked these according to preference in an anonymous vote. The top three suggested evidence gaps were: (i) the comparative risks of managing ACMs in place versus removal; (ii) improved measurement techniques at lower fibre concentrations; and (iii) building the evidence base on the effectiveness of asbestos management and safe removal. HSE will use the workshop outputs to inform its research planning. It is anticipated that a number of initiatives for shared research will be explored. © Crown copyright 2017.

Stability of triptorelin in the presence of dermis and epidermis.

PubMed

Bachhav, Yogeshwar G; Kalia, Yogeshvar N

2009-08-13

An important issue with respect to the transdermal delivery of peptides is their stability during transit through the epidermis and dermis before entry into the systemic circulation. The objective of the present study was to evaluate the effect of epidermal and dermal tissue on the stability of the luteinizing hormone releasing hormone superagonist, triptorelin. The decapeptide was dissolved in PBS (pH 7.4) and placed in contact with (i) heat separated epidermis (HSE), (ii) dermatomed skin (0.75 mm; DS) and (iii) full thickness skin (FTS) and the extent of peptide biotransformation monitored as a function of time by HPLC. The results showed that triptorelin was metabolized when in contact with each of the skin tissues. However, there were marked differences with respect to the extent of peptide degradation. Triptorelin was least stable in the presence of FTS. After 3 h exposure to HSE, DS and FTS, the extent of triptorelin degradation was 15.0+/-6.0%, 64.8+/-9.9% and 100%, respectively. After 24 h, further triptorelin degradation had occurred in the samples in contact with HSE and DS--with 51.3+/-6.0% and 87.8+/-4.4%, respectively, of the peptide being degraded. The chromatograms revealed the presence of a degradation peak at a higher retention time than the parent molecule--most probably the free acid.

Hypertonic saline-epinephrine local injection therapy for post-endoscopic sphincterotomy bleeding: removal of blood clots using pure ethanol local injection.

PubMed

Sakai, Yuji; Tsuyuguchi, Toshio; Sugiyama, Harutoshi; Nishikawa, Takao; Kurosawa, Jo; Saito, Masayoshi; Tawada, Katsunobu; Mikata, Rintaro; Tada, Motohisa; Ishihara, Takeshi; Yokosuka, Osamu

2013-08-01

Bleeding following endoscopic sphincterotomy (EST) is a rare but unavoidable complication of the procedure. We routinely perform local injection of hypertonic saline-epinephrine (HSE) for the treatment of post-EST bleeding. Any blood clot is removed only by irrigation with water after local injection of pure ethanol into the blood clot to cause crusting. We evaluated the usefulness of this treatment method. Subjects were 8 patients (1.2%) with post-EST bleeding requiring hemostatic intervention among 682 patients undergoing EST. After determination of the bleeding point, local injection of HSE was performed. When an adherent blood clot was present, pure ethanol was injected into the blood clot and then irrigation with water was performed to remove the blood clot. Endoscopic hemostasis was successfully achieved in all the 8 patients (100%). In 4 patients (50%), the adherent blood clots were successfully removed only with pure ethanol local injection into the blood clot followed by irrigation with water. No complications of the hemostatic procedure occurred in any patients. This study indicated that hemostasis with HSE local injection can be safe and useful for the treatment of post-EST bleeding, and also that blood clot removal with pure ethanol local injection can be useful.

Evaluation of 3D-human skin equivalents for assessment of human dermal absorption of some brominated flame retardants.

PubMed

Abdallah, Mohamed Abou-Elwafa; Pawar, Gopal; Harrad, Stuart

2015-11-01

Ethical and technical difficulties inherent to studies in human tissues are impeding assessment of the dermal bioavailability of brominated flame retardants (BFRs). This is further complicated by increasing restrictions on the use of animals in toxicity testing, and the uncertainties associated with extrapolating data from animal studies to humans due to inter-species variations. To overcome these difficulties, we evaluate 3D-human skin equivalents (3D-HSE) as a novel in vitro alternative to human and animal testing for assessment of dermal absorption of BFRs. The percutaneous penetration of hexabromocyclododecanes (HBCD) and tetrabromobisphenol-A (TBBP-A) through two commercially available 3D-HSE models was studied and compared to data obtained for human ex vivo skin according to a standard protocol. No statistically significant differences were observed between the results obtained using 3D-HSE and human ex vivo skin at two exposure levels. The absorbed dose was low (less than 7%) and was significantly correlated with log Kow of the tested BFR. Permeability coefficient values showed increasing dermal resistance to the penetration of γ-HBCD>β-HBCD>α-HBCD>TBBPA. The estimated long lag times (>30 min) suggests that frequent hand washing may reduce human exposure to HBCDs and TBBPA via dermal contact. Copyright © 2015 Elsevier Ltd. All rights reserved.

Stabilization of Reactive MgO Surfaces by Ni Doping

NASA Astrophysics Data System (ADS)

Mazheika, Aliaksei; Levchenko, Sergey V.

Ni-MgO solid solutions are promising materials for catalytic reduction of CO2 and dry reforming of CH4. To explain the catalytic activity, an ab initio study of Ni-substitutional defects in MgO (NiMg) has been performed. At first, the validation of the theory level was done. We compared results of CCSD(T) embedded-cluster calculations of NiMg formation energies and adsorption energies of CO, CO2 and H2 on them to the HSE(α) hybrid DFT functional with the fraction of the exact exchange α varied between 0 and 1. HSE(0.3) was found to be the best compromise in this study. Our periodic HSE(0.3) calculations show that NiMg defects are most stable at corner sites, followed by steps, and are least stable at (001) terraces. Thus, Ni-doping stabilizes stepped MgO surfaces. The dissociative adsorption of H2 on the terrace is found to be endothermic (+ 1 . 1 eV), whereas on (110) surface with NiMg it is highly exothermic (- 1 . 6 eV). Adsorbed CO2 is also significantly stabilized (- 0 . 6 vs. - 2 . 2 eV). These findings explain recent microcalorimetry measurements of H2 and CO2 adsorption at doped Ni-MgO samples. partially supported by UniCat (Deutsche Forschungsgemeinschaft).

U. K. pressing campaign to improve offshore safety

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knott, D.

1994-02-14

The U.K. government is making progress in its campaign to improve the safety of personnel working offshore. The government's Health and Safety Executive (HSE) plans to assess and pass judgment on at lease one safety plan, called a safety case, from each U.K. North Sea operator as soon as possible. HSE has agreed with the industry on a list of 61 priority safety cases, known as exemplars. Feedback from exemplar assessment will help operators review safety management and assist in preparation or revision of future safety cases. It also will give HSE practice in assessing a range of case types.more » The requirement for a safety program is part of new U.K. offshore legislation designed to prevent another accident similar to the Piper Alpha platform fire and explosion of 1988. After the transition period it will be against the law to operate an oil and gas installation in British waters without an accepted safety case. Besides existing installations, safety cases are also required for new installations reaching design stage by May 31, 1993, the date safety case regulations went into force. The paper describes the Cullen report, companies' experiences with the new law, and the safety assessment progress so far.« less

Validation of the Italian version of the HSE Indicator Tool.

PubMed

Magnavita, N

2012-06-01

An Italian version of the Health & Safety Executive's (HSE) Management Standards Revised Indicator Tool (MS-RIT) has been used to monitor the working conditions that may lead to stress. To initially examine the factor structure of the Italian version of the MS-RIT, in comparison with the original UK tool, and to investigate its validity and reliability; second, to study the association between occupational stress and psychological distress. Workers from 17 companies self-completed the MS-RIT and the General Health Questionnaire used to measure the psychological distress while they waited for their periodic examination at the workplace. Factor analysis was employed to ascertain whether the Italian version maintained the original subdivision into seven scales. Odds ratios were calculated to estimate the risk of impairment associated with exposure to stress at the workplace. In total, 748 workers participated; the response rate was 91%. The factor structure of the Italian MS-RIT corresponded partially to the original UK version. The 'demand', 'control', 'role', ' relationship' and 'colleague-support' scales were equivalent to the UK ones. A principal factor, termed ' elasticity', incorporated the UK 'management-support' and 'change' scales. Reliability analysis of the sub-scales revealed Cronbach's alpha values ranging from 0.75 to 0.86. Our findings confirmed the usefulness of the Italian version of the HSE MS-RIT in stress control.

Effect of Selenium Supplementation on Redox Status of the Aortic Wall in Young Spontaneously Hypertensive Rats

PubMed Central

Ruseva, Boryana; Atanasova, Milena; Tsvetkova, Reni; Betova, Tatyana; Mollova, Margarita; Alexandrova, Margarita; Laleva, Pavlina; Dimitrova, Aneliya

2015-01-01

Selenium (Se) is an exogenous antioxidant that performs its function via the expression of selenoproteins. The aim of this study was to explore the effect of varying Se intake on the redox status of the aortic wall in young spontaneously hypertensive rats (SHR). Sixteen male Wistar Kyoto (WKY) rats and nineteen male SHR, 16-week-old, were tested after being given diets with different Se content for eight weeks. They were divided into 4 groups: control groups of WKY NSe and SHR NSe on an adequate Se diet and groups of WKY HSe and SHR HSe that received Se supplementation. The Se nutritional status was assessed by measuring whole blood glutathione peroxidase-1 (GPx-1) activity. Serum concentration of lipid hydroperoxides and serum level of antibodies against advanced glycation end products (anti-AGEs abs) were determined. Expression of GPx-1 and endothelial nitric oxide synthase (eNOS) were examined in aortic wall. Se supplementation significantly increased GPx-1 activity of whole blood and in the aortas of WKY and SHR. Decreased lipid peroxidation level, eNOS-3 expression in the aortic wall, and serum level of anti-AGEs abs were found in SHR HSe compared with SHR NSe. In conclusion, Se supplementation improved the redox status of the aortic wall in young SHR. PMID:26473024

Origin of the Permian-Triassic komatiites, northwestern Vietnam

NASA Astrophysics Data System (ADS)

Hanski, Eero; Walker, Richard J.; Huhma, Hannu; Polyakov, Gleb V.; Balykin, Pavel A.; Tran Trong Hoa; Ngo Thi Phuong

Rare examples of Phanerozoic komatiites are found in the Song Da zone, NW Vietnam. These komatiites were erupted through continental crust and may belong to the SE extension of the Permo-Triassic Emeishan volcanic province located in SW China. They provide a good opportunity to study the source characteristics of starting plume magmas in a continental flood basalt province. Erupted on late-Permian carbonate rocks, the komatiitic rocks are interbedded with low-Ti olivine basalts. Basaltic komatiites display pyroxene spinifex textures, while more magnesian rocks (MgO up to 32 wt.%) are porphyritic, containing a single, cognate population of euhedral to elongated olivine phenocrysts with Fo up to 93.0%. This suggests a highly magnesian parental magma with 22-23 wt.% MgO. In terms of major and minor elements, the komatiites are similar to the ca. 89 Ma old Gorgona Island komatiites of Colombia. The Song Da komatiites are also strongly light-rare-earth-element- (LREE) depleted (CeN/YbN 0.30-0.62) and have unfractionated heavy rare earth element (HREE) patterns. The komatiites have high Os concentrations (up to 7.0 ppb), low but variable Re/Os ratios, and define an isochron with an age of 270+/-21 Ma, and an initial 188Os/187Os ratio of 0.12506+/- 0.00041 (γOs=+0.02+/-0.40). The Os isotopic systematics of the komatiites show no effects of crustal contamination. In contrast, their initial ɛNd values range from +3 to +8, reflecting varying but generally small degrees of contamination with Proterozoic sialic basement material. Associated low-Ti basalts have low initial ɛNd values (-0.8 to -7.5), high initial γOs values (>=15), flat or LREE-enriched REE patterns, and Nb-Ta depletion. These characteristics are also attributed to variable extents of crustal contamination.

Supra-optimal expression of the cold-regulated OsMyb4 transcription factor in transgenic rice changes the complexity of transcriptional network with major effects on stress tolerance and panicle development.

PubMed

Park, Myoung-Ryoul; Yun, Kil-Young; Mohanty, Bijayalaxmi; Herath, Venura; Xu, Fuyu; Wijaya, Edward; Bajic, Vladimir B; Yun, Song-Joong; De Los Reyes, Benildo G

2010-12-01

The R2R3-type OsMyb4 transcription factor of rice has been shown to play a role in the regulation of osmotic adjustment in heterologous overexpression studies. However, the exact composition and organization of its underlying transcriptional network has not been established to be a robust tool for stress tolerance enhancement by regulon engineering. OsMyb4 network was dissected based on commonalities between the global chilling stress transcriptome and the transcriptome configured by OsMyb4 overexpression. OsMyb4 controls a hierarchical network comprised of several regulatory sub-clusters associated with cellular defense and rescue, metabolism and development. It regulates target genes either directly or indirectly through intermediary MYB, ERF, bZIP, NAC, ARF and CCAAT-HAP transcription factors. Regulatory sub-clusters have different combinations of MYB-like, GCC-box-like, ERD1-box-like, ABRE-like, G-box-like, as1/ocs/TGA-like, AuxRE-like, gibberellic acid response element (GARE)-like and JAre-like cis-elements. Cold-dependent network activity enhanced cellular antioxidant capacity through radical scavenging mechanisms and increased activities of phenylpropanoid and isoprenoid metabolic processes involving various abscisic acid (ABA), jasmonic acid (JA), salicylic acid (SA), ethylene and reactive oxygen species (ROS) responsive genes. OsMyb4 network is independent of drought response element binding protein/C-repeat binding factor (DREB/CBF) and its sub-regulons operate with possible co-regulators including nuclear factor-Y. Because of its upstream position in the network hierarchy, OsMyb4 functions quantitatively and pleiotrophically. Supra-optimal expression causes misexpression of alternative targets with costly trade-offs to panicle development. © 2010 Blackwell Publishing Ltd.

Bariatric Surgery in Obese Women of Reproductive Age Improves Conditions That Underlie Fertility and Pregnancy Outcomes: Retrospective Cohort Study of UK National Bariatric Surgery Registry (NBSR).

PubMed

Edison, Eric; Whyte, Martin; van Vlymen, Jeremy; Jones, Simon; Gatenby, Piers; de Lusignan, Simon; Shawe, Jill

2016-12-01

The aims of this study are the following: to describe the female population of reproductive age having bariatric surgery in the UK, to assess the age and ethnicity of women accessing surgery, and to assess the effect of bariatric surgery on factors that underlie fertility and pregnancy outcomes. Demographic details, comorbidities, and operative type of women aged 18-45 years were extracted from the National Bariatric Surgery Registry (NBSR). A comparison was made with non-operative cases (aged 18-45 and BMI ≥40 kg/m 2 ) from the Health Survey for England (HSE, 2007-2013). Analyses were performed using "R" software. Data were extracted on 15,222 women from NBSR and 1073 from HSE. Women aged 18-45 comprised 53 % of operations. Non-Caucasians were under-represented in NBSR compared to HSE (10 vs 16 % respectively, p < 0.0001). The NBSR group was older than the HSE group-median 38 (IQR 32-42) vs 36 (IQR 30-41) years (Wilcoxon test p < 0.0001). Almost one third of women in NBSR had menstrual dysfunction at baseline (33.0 %). BMI fell in the first year postoperatively from 48.2 ± 8.3 to 37.4 ± 7.5 kg/m 2 (t test, p < 0.001). From NBSR, in the postoperative period, the prevalence of type 2 diabetes fell by 54 %, polycystic ovarian syndrome by 15 %, and any menstrual dysfunction by 12 %. Over half of all bariatric procedures are carried out on women of reproductive age. More work is required to provide prompt and equal access across ethnic groups. At least one in three women suffers from menstrual dysfunction at baseline. Bariatric surgery improves factors that underlie fertility and pregnancy outcomes. A prospective study is required to verify these effects.

Re-Os isotopic systematics of primitive lavas from the Lassen region of the Cascade arc, California

USGS Publications Warehouse

Borg, L.E.; Brandon, A.D.; Clynne, M.A.; Walker, R.J.

2000-01-01

Rhenium-osmium isotopic systematics of primitive calc-alkaline lavas from the Lassen region appear to be controlled by mantle wedge processes. Lavas with a large proportion of slab component have relatively low Re and Os abundances, and have radiogenic Os and mid ocean ridge basalt-like Sr and Pb isotopic compositions. Lavas with a small proportion of slab component have higher Re and Os elemental abundances and display mantle-like Os, Sr, Nd, and Pb isotopic compositions. Assimilation with fractional crystallization can only generate the Re-Os systematics of the Lassen lavas from a common parent if the distribution coefficient for Re in sulfide is ~40-1100 times higher than most published estimates and if most incompatible element abundances decrease during differentiation. High Re/Os ratios in mid ocean ridge basalts makes subducted oceanic crust a potential source of radiogenic Os in volcanic arcs. The slab beneath the southernmost Cascades is estimated to have 187Os/188Os ratios as high as 1.4. Mixing between a slab component and mantle wedge peridotite can generate the Os isotopic systematics of the Lassen lavas provided the slab component has a Sr/Os ratio of ~7.5X105 and Os abundances that are 100-600 times higher than mid ocean ridge basalts. For this model to be correct, Os must be readily mobilized and concentrated in the slab component, perhaps as a result of high water and HCl fugacities in this subduction environment. Another possible mechanism to account for the correlation between the magnitude of the subduction geochemical signature and Os isotopic composition involves increasing the stability of an Os-bearing phase in mantle wedge peridotites as a result of fluxing with the slab component. Melting of such a source could yield low Os magmas that are more susceptible to crustal contamination, and hence have more radiogenic Os isotopic compositions, than magmas derived from sources with a smaller contribution from the slab. Thus, the addition of the slab component to the mantle wedge appears to result in either the direct or indirect addition of radiogenic Os to arc magmas. (C) 2000 Elsevier Science B.V. All rights reserved.

Dietary selenium and nutritional plane alter specific aspects of maternal endocrine status during pregnancy and lactation.

PubMed

Lemley, C O; Meyer, A M; Neville, T L; Hallford, D M; Camacho, L E; Maddock-Carlin, K R; Wilmoth, T A; Wilson, M E; Perry, G A; Redmer, D A; Reynolds, L P; Caton, J S; Vonnahme, K A

2014-01-01

Objectives were to examine effects of selenium (Se) supply and maternal nutritional plane during gestation on placental size at term and maternal endocrine profiles throughout gestation and early lactation. Ewe lambs (n = 84) were allocated to treatments that included Se supply of adequate Se (ASe; 11.5 μg/kg BW) or high Se (HSe; 77 μg/kg BW) initiated at breeding and nutritional plane of 60% (RES), 100% (CON), or 140% (EXC) of requirements beginning on day 40 of gestation. At parturition, lambs were removed from their dams, and ewes were transitioned to a common diet that met requirements of lactation. Blood samples were taken from a subset of ewes (n = 42) throughout gestation, during parturition, and throughout lactation to determine hormone concentrations. Cotyledon number was reduced (P = 0.03) in RES and EXC ewes compared with CON ewes. Placental delivery time tended (P = 0.08) to be shorter in HSe ewes than in ASe ewes, whereas placental delivery time was longer (P = 0.02) in RES ewes than in CON and EXC ewes. During gestation, maternal progesterone, estradiol-17β, and GH were increased (P < 0.05) in RES ewes and decreased (P < 0.05) in EXC ewes compared with CON ewes. In contrast, maternal cortisol, IGF-I, prolactin, triiodothyronine, and thyroxine were decreased in RES ewes and increased in EXC ewes compared with CON ewes during gestation. Selenium supply did not alter maternal hormone profiles during gestation. During parturition and lactation, maternal hormone concentrations were influenced by both Se and maternal nutritional plane. During the parturient process, HSe ewes tended to have greater (P = 0.06) concentrations of estradiol-17β than ASe ewes. Three hours after parturition a surge of GH was observed in ASe-RES ewes that was muted in HSe-RES ewes and not apparent in other ewes. Growth hormone area under the curve during the parturient process was increased (P < 0.05) in ASe-RES vs HSe-RES ewes. Ewes that were overfed during gestation had reduced (P < 0.05) estradiol-17β but greater IGF-I, triiodothyronine, and thyroxine (P < 0.05) compared with RES ewes. Even though ewes were transitioned to a common diet after parturition, endocrine status continued to be affected into lactation. Moreover, it appears that gestational diet may partially affect lactational performance through altered endocrine status. Copyright © 2014 Elsevier Inc. All rights reserved.

Interactions between Nitrogen and Silicon in Rice and Their Effects on Resistance toward the Brown Planthopper Nilaparvata lugens

PubMed Central

Wu, Xiaoying; Yu, Yaoguang; Baerson, Scott R.; Song, Yuanyuan; Liang, Guohua; Ding, Chaohui; Niu, Jinbo; Pan, Zhiqiang; Zeng, Rensen

2017-01-01

Nitrogen (N) and silicon (Si) are two important nutritional elements required for plant growth, and both impact host plant resistance toward insect herbivores. The interaction between the two elements may therefore play a significant role in determining host plant resistance. We investigated this interaction in rice (Oryza sativa L.) and its effect on resistance to the herbivore brown planthopper Nilaparvata lugens (BPH). Our results indicate that high-level (5.76 mM) N fertilization reduced Si accumulation in rice leaves, and furthermore, this decrease was likely due to decreased expression of Si transporters OsLsi1 and OsLsi2. Conversely, reduced N accumulation was observed at high N fertilization levels when Si was exogenously provided, and this was associated with down-regulation of OsAMT1;1 and OsGS1;1, which are involved in ammonium uptake and assimilation, respectively. Under lower N fertilization levels (0.72 and/or 1.44 mM), Si amendment resulted in increased OsNRT1:1, OsGS2, OsFd-GOGAT, OsNADH-GOGAT2, and OsGDH2 expression. Additionally, bioassays revealed that high N fertilization level significantly decreased rice resistance to BPH, and the opposite effect was observed when Si was provided. These results provide additional insight into the antagonistic interaction between Si and N accumulation in rice, and the effects on plant growth and susceptibility to herbivores. PMID:28167952

Oxidative stress damage as a detrimental factor in preterm birth pathology.

PubMed

Menon, Ramkumar

2014-01-01

Normal term and spontaneous preterm births (PTB) are documented to be associated with oxidative stress (OS), and imbalances in the redox system (balance between pro- and antioxidant) have been reported in the maternal-fetal intrauterine compartments. The exact mechanism of labor initiation either at term or preterm by OS is still unclear, and this lack of understanding can partially be blamed for failure of antioxidant supplementation trials in PTB prevention. Based on recent findings from our laboratory, we postulate heterogeneity in host OS response. The physiologic (at term) and pathophysiologic (preterm) pathways of labor are not mediated by OS alone but by OS-induced damage to intrauterine tissues, especially fetal membranes of the placenta. OS damage affects all major cellular elements in the fetal cells, and this damage promotes fetal cell senescence (aging). The aging of the fetal cells is predominated by p38 mitogen activated kinase (p38MAPK) pathways. Senescing cells generate biomolecular signals that are uterotonic, triggering labor process. The aging of fetal cells is normal at term. However, aging is premature in PTB, especially in those PTBs complicated by preterm premature rupture of the membranes, where elements of redox imbalances and OS damage are more dominant. We postulate that fetal cell senescence signals generated by OS damage are likely triggers for labor. This review highlights the mechanisms involved in senescence development at term and preterm by OS damage and provides insight into novel fetal signals of labor initiation pathways.

Oxidative Stress Damage as a Detrimental Factor in Preterm Birth Pathology

PubMed Central

Menon, Ramkumar

2014-01-01

Normal term and spontaneous preterm births (PTB) are documented to be associated with oxidative stress (OS), and imbalances in the redox system (balance between pro- and antioxidant) have been reported in the maternal–fetal intrauterine compartments. The exact mechanism of labor initiation either at term or preterm by OS is still unclear, and this lack of understanding can partially be blamed for failure of antioxidant supplementation trials in PTB prevention. Based on recent findings from our laboratory, we postulate heterogeneity in host OS response. The physiologic (at term) and pathophysiologic (preterm) pathways of labor are not mediated by OS alone but by OS-induced damage to intrauterine tissues, especially fetal membranes of the placenta. OS damage affects all major cellular elements in the fetal cells, and this damage promotes fetal cell senescence (aging). The aging of the fetal cells is predominated by p38 mitogen activated kinase (p38MAPK) pathways. Senescing cells generate biomolecular signals that are uterotonic, triggering labor process. The aging of fetal cells is normal at term. However, aging is premature in PTB, especially in those PTBs complicated by preterm premature rupture of the membranes, where elements of redox imbalances and OS damage are more dominant. We postulate that fetal cell senescence signals generated by OS damage are likely triggers for labor. This review highlights the mechanisms involved in senescence development at term and preterm by OS damage and provides insight into novel fetal signals of labor initiation pathways. PMID:25429290

Discovery of a Thorne-Żytkow object candidate in the Small Magellanic Cloud

NASA Astrophysics Data System (ADS)

Levesque, Emily M.; Massey, Philip; Żytkow, Anna N.; Morrell, Nidia

2015-01-01

Thorne-Żytkow objects (TŻOs) are a theoretical class of star in which a compact neutron star is surrounded by a large, diffuse envelope. Supergiant TŻOs are predicted to be almost identical in appearance to red supergiants (RSGs), with their very red colors and cool temperatures placing them at the Hayashi limit on the H-R diagram. The only features that can be used at present to distinguish TŻOs from the general RSG population are the unusually strong heavy-element and lithium lines present in their spectra. These elements are the unique products of the stars fully convective envelope linking the photosphere with the extraordinarily hot burning region in the vicinity of the neutron star core. We have recently discovered a TŻO candidate in the Small Magellanic Cloud. It is the first star to display the distinctive chemical profile of anomalous element enhancements thought to be characteristic of TŻOs however, up-to-date models and additional observable predictions (including potential asteroseismological signatures) are required to solidify this discovery. The definitive detection of a TŻO would provide the first direct evidence for a completely new model of stellar interiors, a theoretically predicted fate for massive binary systems, and never-before-seen nucleosynthesis processes that would offer a new channel for heavy-element and lithium production in our universe.

A Crossover from High Stiffness to High Hardness: The Case of Osmium and Its Borides

NASA Astrophysics Data System (ADS)

Bian, Yongming; Liu, Xiaomei; Li, Anhu; Liang, Yongcheng

2016-09-01

Transition-metal light-element compounds are currently raising great expectations for hard and superhard materials. Using the widely attracting osmium (Os) and its borides (OsB, Os2B3 and OsB2) as prototypes, we demonstrate by first-principles calculations that heavy transition metals, which possess high stiffness but low hardness, can be converted into highly hard materials by incorporating of light elements to form compounds. Such a crossover is a manifestation that the underlying sources of high stiffness and high hardness are fundamentally different. The stiffness is related to elastic deformation that is closely associated with valence electron density, whereas the hardness depends strongly on plastic deformation that is determined by bonding nature. Therefore, the incorporation of light atoms into transition metal should be a valid pathway of designing hard and superhard materials. This strategy is in principle also applicable to other transition-metal borides, carbides, and nitrides.

Overexpression of the OsIMP Gene Increases the Accumulation of Inositol and Confers Enhanced Cold Tolerance in Tobacco through Modulation of the Antioxidant Enzymes' Activities.

PubMed

Zhang, Rong-Xiang; Qin, Li-Jun; Zhao, De-Gang

2017-07-20

Inositol is a cyclic polyol that is involved in various physiological processes, including signal transduction and stress adaptation in plants. l- myo -inositol monophosphatase (IMPase) is one of the metal-dependent phosphatase family members and catalyzes the last reaction step of biosynthesis of inositol. Although increased IMPase activity induced by abiotic stress has been reported in chickpea plants, the role and regulation of the IMP gene in rice ( Oryza sativa L.) remains poorly understood. In the present work, we obtained a full-length cDNA sequence coding IMPase in the cold tolerant rice landraces in Gaogonggui, which is named as OsIMP . Multiple alignment results have displayed that this sequence has characteristic signature motifs and conserved enzyme active sites of the phosphatase super family. Phylogenetic analysis showed that IMPase is most closely related to that of the wild rice Oryza brachyantha , while transcript analysis revealed that the expression of the OsIMP is significantly induced by cold stress and exogenous abscisic acid (ABA) treatment. Meanwhile, we cloned the 5' flanking promoter sequence of the OsIMP gene and identified several important cis -acting elements, such as LTR (low-temperature responsiveness), TCA-element (salicylic acid responsiveness), ABRE-element (abscisic acid responsiveness), GARE-motif (gibberellin responsive), MBS (MYB Binding Site) and other cis -acting elements related to defense and stress responsiveness. To further investigate the potential function of the OsIMP gene, we generated transgenic tobacco plants overexpressing the OsIMP gene and the cold tolerance test indicated that these transgenic tobacco plants exhibit improved cold tolerance. Furthermore, transgenic tobacco plants have a lower level of hydrogen peroxide (H₂O₂) and malondialdehyde (MDA), and a higher content of total chlorophyll as well as increased antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD), when compared to wild type (WT) tobacco plants under normal and cold stress conditions.

Transferable tight-binding model for strained group IV and III-V materials and heterostructures

NASA Astrophysics Data System (ADS)

Tan, Yaohua; Povolotskyi, Michael; Kubis, Tillmann; Boykin, Timothy B.; Klimeck, Gerhard

2016-07-01

It is critical to capture the effect due to strain and material interface for device level transistor modeling. We introduce a transferable s p3d5s* tight-binding model with nearest-neighbor interactions for arbitrarily strained group IV and III-V materials. The tight-binding model is parametrized with respect to hybrid functional (HSE06) calculations for varieties of strained systems. The tight-binding calculations of ultrasmall superlattices formed by group IV and group III-V materials show good agreement with the corresponding HSE06 calculations. The application of the tight-binding model to superlattices demonstrates that the transferable tight-binding model with nearest-neighbor interactions can be obtained for group IV and III-V materials.

Does self-threat promote social connection? The role of self-esteem and contingencies of self-worth.

PubMed

Park, Lora E; Maner, Jon K

2009-01-01

Six studies examined the social motivations of people with high self-esteem (HSE) and low self-esteem (LSE) following a threat to a domain of contingent self-worth. Whether people desired social contact following self-threat depended on an interaction between an individual's trait self-esteem and contingencies of self-worth. HSE participants who strongly based self-worth on appearance sought to connect with close others following a threat to their physical attractiveness. LSE participants who staked self-worth on appearance wanted to avoid social contact and, instead, preferred a less interpersonally risky way of coping with self-threat (wanting to enhance their physical attractiveness). Implications for theories of self-esteem, motivation, and interpersonal processes are discussed.

Light and abiotic stresses regulate the expression of GDP-L-galactose phosphorylase and levels of ascorbic acid in two kiwifruit genotypes via light-responsive and stress-inducible cis-elements in their promoters.

PubMed

Li, Juan; Liang, Dong; Li, Mingjun; Ma, Fengwang

2013-09-01

Ascorbic acid (AsA) plays an essential role in plants by protecting cells against oxidative damage. GDP-L-galactose phosphorylase (GGP) is the first committed gene for AsA synthesis. Our research examined AsA levels, regulation of GGP gene expression, and how these are related to abiotic stresses in two species of Actinidia (kiwifruit). When leaves were subjected to continuous darkness or light, ABA or MeJA, heat, or a hypoxic environment, we found some correlation between the relative levels of GGP mRNA and AsA concentrations. In transformed tobacco plants, activity of the GGP promoter was induced by all of these treatments. However, the degree of inducibility in the two kiwifruit species differed among the GGP promoter deletions. We deduced that the G-box motif, a light-responsive element, may have an important function in regulating GGP transcripts under various light conditions in both A. deliciosa and A. eriantha. Other elements such as ABRE, the CGTCA motif, and HSE might also control the promoter activities of GGP in kiwifruit. Altogether, these data suggest that GGP expression in the two kiwifruit species is regulated by light or abiotic stress via the relative cis-elements in their promoters. Furthermore, GGP has a critical role in modulating AsA concentrations in kiwifruit species under abiotic stresses.

Reappraising Accretion to Vesta and the Angrite Parent Body Through Mineral-Scale Platinum Group Element and Os-Isotope Analyses

NASA Astrophysics Data System (ADS)

Riches, A. J. V.; Burton, K. W.; Nowell, G. M.; Dale, C. W.; Ottley, C. J.

2016-08-01

New methods presented here enable quantitative determination of mineral-scale PGE-abundances and Os-isotope compositions in meteorite materials thereby providing valuable new insight into planetary evolution.

Penta-SiC5 monolayer: A novel quasi-planar indirect semiconductor with a tunable wide band gap

NASA Astrophysics Data System (ADS)

Naseri, Mosayeb

2018-03-01

In this paper, by using of the first principles calculations in the framework of the density functional theory, we systematically investigated the structure, stability, electronic and optical properties of a novel two-dimensional pentagonal monolayer semiconductors namely penta-SiC5 monolayer. Comparing elemental silicon, diamond, and previously reported 2D carbon allotropes, our calculation shows that the predicted penta-SiC5 monolayer has a metastable nature. The calculated results indicate that the predicted monolayer is an indirect semiconductor with a wide band gap of about 2.82 eV by using Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional level of theory which can be effectively tuned by external biaxial strains. The obtained exceptional electronic properties suggest penta-SiC5 monolayer as promising candidates for application in new electronic devices in nano scale.

Copper disinfection ban causes storm.

PubMed

Lester, Alan

2013-05-01

Since 1 February this year, under the EU's Biocidal Products Directive, it has been illegal to sell or use water treatment systems that use elemental copper, a practice employed historically by a significant number of UK healthcare facilities to combat Legionella. Alan Lester, managing director of specialist supplier of 'environmentally-friendly' water treatment systems, Advanced Hydro, says the ban has caused 'a storm of giant proportion,' with advocates of copper ion-based treatment systems arguing that this disinfection method dates back 3,000 years to Egyptian times, making it an 'undoubtedly proven' technology. Here he explains why the ban came into force, considers why the UK's Health and Safety Executive (HSE) is seeking a derogation, looks at the ban's likely impact, and gives a personal viewpoint on the 'pros and cons' of some of the alternative treatment technologies, including a titanium dioxide-based system marketed by Advanced Hydro itself in the UK.

A colossal impact enriched Mars' mantle with noble metals

NASA Astrophysics Data System (ADS)

Brasser, R.; Mojzsis, S. J.

2017-06-01

Once the terrestrial planets had mostly completed their assembly, bombardment continued by planetesimals left over from accretion. Highly siderophile element (HSE) abundances in Mars' mantle imply that its late accretion supplement was 0.8 wt %; Earth and the Moon obtained an additional 0.7 wt % and 0.02 wt %, respectively. The disproportionately high Earth/Moon accretion ratio is explicable by stochastic addition of a few remaining Ceres-sized bodies that preferentially targeted Earth. Here we show that Mars' late accretion budget also requires a colossal impact, a plausible visible remnant of which is the emispheric dichotomy. The addition of sufficient HSEs to the Martian mantle entails an impactor of at least 1200 km in diameter to have struck Mars before 4430 Ma, by which time crust formation was well underway. Thus, the dichotomy could be one of the oldest geophysical features of the Martian crust. Ejected debris could be the source material for its satellites.

Re-Os isotope and platinum group elements of a FOcal ZOne mantle source, Louisville Seamounts Chain, Pacific ocean

NASA Astrophysics Data System (ADS)

Tejada, Maria Luisa G.; Hanyu, Takeshi; Ishikawa, Akira; Senda, Ryoko; Suzuki, Katsuhiko; Fitton, Godfrey; Williams, Rebecca

2015-02-01

The Louisville Seamount Chain (LSC) is, besides the Hawaiian-Emperor Chain, one of the longest-lived hotspot traces. We report here the first Re-Os isotope and platinum group element (PGE) data for Canopus, Rigil, and Burton Guyots along the chain, which were drilled during IODP Expedition 330. The LSC basalts possess (187Os/188Os)i = 0.1245-0.1314 that are remarkably homogeneous and do not vary with age. A Re-Os isochron age of 64.9 ± 3.2 Ma was obtained for Burton seamount (the youngest of the three seamounts drilled), consistent with 40Ar-39Ar data. Isochron-derived initial 187Os/188Os ratio of 0.1272 ± 0.0008, together with data for olivines (0.1271-0.1275), are within the estimated primitive mantle values. This (187Os/188Os)i range is similar to those of Rarotonga (0.124-0.139) and Samoan shield (0.1276-0.1313) basalts and lower than those of Cook-Austral (0.136-0.155) and Hawaiian shield (0.1283-0.1578) basalts, suggesting little or no recycled component in the LSC mantle source. The PGE data of LSC basalts are distinct from those of oceanic lower crust. Variation in PGE patterns can be largely explained by different low degrees of melting under sulfide-saturated conditions of the same relatively fertile mantle source, consistent with their primitive mantle-like Os and primordial Ne isotope signatures. The PGE patterns and the low 187Os/188Os composition of LSC basalts contrast with those of Ontong Java Plateau (OJP) tholeiites. We conclude that the Re-Os isotope and PGE composition of LSC basalts reflect a relatively pure deep-sourced common mantle sampled by some ocean island basalts but is not discernible in the composition of OJP tholeiites.

Sulfide and whole rock Re-Os systematics of eclogite and pyroxenite xenoliths from the Slave Craton, Canada

NASA Astrophysics Data System (ADS)

Aulbach, Sonja; Creaser, Robert A.; Pearson, Norm J.; Simonetti, Stefanie S.; Heaman, Larry M.; Griffin, William L.; Stachel, Thomas

2009-06-01

We characterized single sulfides in eclogite and pyroxenite xenoliths from the Diavik kimberlites (central Slave Craton, Canada) with regard to their petrography, major-element composition and Re-Os isotope systematics. Together with trace-element and Re-Os isotope compositions of whole rocks, these data allow identification of the major Re-Os host phases and provide constraints on the origin(s) of sulfides in these samples. The majority of sulfide minerals contain 8 to 28 at.% Ni, with intragranular sulfides having on average significantly lower contents (~ 6 at.%) than intergranular sulfides (~ 12 at.%). These high Ni-sulfides are not in equilibrium with an eclogitic assemblage and were likely introduced from a peridotitic source subsequent to eclogite formation. In contrast, their Re-Os abundances and Re/Os ratios (average ~ 825 ppb, 190 ppb and 10, respectively) overlap those of primary eclogitic sulfides. These conflicting compositional characteristics may document open-system disequilibrium processes accompanying the introduction of sulfides into eclogites. The general association of high 187Os/ 188Os with high 187Re/ 188Os of sulfides in three low-temperature eclogite xenoliths suggests that the addition is not young. In contrast, sulfides in a high-temperature eclogite plot on a ~ 90 Ma errorchron with radiogenic initial 187Os/ 188Os, perhaps indicative of young introduction of sulfides from a deep enriched source. Sulfides in a single pyroxenite xenolith have Ni, Re and Os contents intermediate between pristine eclogitic and peridotitic sulfides, and correlated Re-Os isotope systematics defining an age of 1.84 ± 0.14 Ga with a radiogenic 187Os/ 188Os i (0.16 ± 0.01). The age and 187Os/ 188Os i are identical to those obtained for eclogitic sulfide inclusions in diamonds from Diavik, thus supporting a link between eclogite and pyroxenite formation. Several eclogite and pyroxenite whole rocks show evidence for addition of secondary sulfides, but many plot on Paleoproterozoic Re-Os age arrays - particularly so at low Re/Os - coincident with previously determined ages using Lu-Hf and Pb-Pb techniques. They may represent sulfide-poor varieties that did not suffer secondary sulfide addition and that may be best suited to yielding meaningful Re-Os ages.

On the Highest Oxidation States of Metal Elements in MO4 Molecules (M = Fe, Ru, Os, Hs, Sm, and Pu).

PubMed

Huang, Wei; Xu, Wen-Hua; Schwarz, W H E; Li, Jun

2016-05-02

Metal tetraoxygen molecules (MO4, M = Fe, Ru, Os, Hs, Sm, Pu) of all metal atoms M with eight valence electrons are theoretically studied using density functional and correlated wave function approaches. The heavier d-block elements Ru, Os, Hs are confirmed to form stable tetraoxides of Td symmetry in (1)A1 electronic states with empty metal d(0) valence shell and closed-shell O(2-) ligands, while the 3d-, 4f-, and 5f-elements Fe, Sm, and Pu prefer partial occupation of their valence shells and peroxide or superoxide ligands at lower symmetry structures with various spin couplings. The different geometric and electronic structures and chemical bonding types of the six iso-stoichiometric species are explained in terms of atomic orbital energies and orbital radii. The variations found here contribute to our general understanding of the periodic trends of oxidation states across the periodic table.

Chemical weathering on the North Island of New Zealand: CO2 consumption and fluxes of Sr and Os

NASA Astrophysics Data System (ADS)

Blazina, Tim; Sharma, Mukul

2013-09-01

We present Os and Sr isotope ratios and Os, Sr and major/trace element concentrations for river waters, spring waters and rains on the North Island of New Zealand. The Os and Sr data are used to examine whether the NINZ is a significant contributor of unradiogenic Os and Sr to the oceans. Major element chemistry is used to quantify weathering and CO2 consumption rates on the island to investigate relationships between these processes and Os and Sr behavior. Chemical erosion rates and CO2 consumption rates across the island range from 44 to 555 km-2 yr-1 and 95 to 1900 × 103 mol CO2 km-2 yr-1, respectively. Strontium flux for the island range from 177 to 16,100 mol km-2 yr-1 and the rivers have an average flux normalized 87Sr/86Sr ratio of 0.7075. In agreement with the previous studies these findings provide further evidence that weathering of arc terrains contributes a disproportionally large amount of Sr to the oceans and consumes very large amounts of CO2 annually compared to their areal extent. However, the 87Sr/86Sr from the NINZ is not particularly unradiogenic and it is likely not contributing significant amounts of unradiogenic Sr to the oceans. Repeated Os analyses and bottle leaching experiments revealed extensive and variable sample contamination by Os leaching from rigorously precleaned LDPE bottles. An upper bound on the flux of Os from NINZ can nevertheless be assessed and indicates that island arcs cannot provide significant amounts of unradiogenic Os to the oceans.

Development of functional beverages from blends of Hibiscus sabdariffa extract and selected fruit juices for optimal antioxidant properties.

PubMed

Ogundele, Oluwatoyin M A; Awolu, Olugbenga O; Badejo, Adebanjo A; Nwachukwu, Ifeanyi D; Fagbemi, Tayo N

2016-09-01

The demand for functional foods and drinks with health benefit is on the increase. The synergistic effect from mixing two or more of such drinks cannot be overemphasized. This study was carried out to formulate and investigate the effects of blends of two or more of pineapple, orange juices, carrot, and Hibiscus sabdariffa extracts (HSE) on the antioxidant properties of the juice formulations in order to obtain a combination with optimal antioxidant properties. Experimental design was carried out using optimal mixture model of response surface methodology which generated twenty experimental runs with antioxidant properties as the responses. The DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)] radical scavenging abilities, ferric reducing antioxidant potential (FRAP), vitamin C, total phenolics, and total carotenoids contents of the formulations were evaluated as a test of antioxidant property. In all the mixtures, formulations having HSE as part of the mixture showed the highest antioxidant potential. The statistical analyzes, however, showed that the formulations containing pineapple, carrot, orange, and HSE of 40.00, 16.49, 17.20, and 26.30%, respectively, produced optimum antioxidant potential and was shown to be acceptable to a research laboratory guidance panel, thus making them viable ingredients for the production of functional beverages possessing important antioxidant properties with potential health benefits.

Hybrid density functional study of bandgaps for 27 new proposed half-Heusler semiconductors

NASA Astrophysics Data System (ADS)

Shi, Fangyi; Si, M. S.; Xie, Jiafeng; Mi, Kui; Xiao, Chuntao; Luo, Qiangjun

2017-12-01

Recently, 27 new half-Heusler compounds XYZ (X = Co, Rh, Fe, Ru, Ni; Y = Sc, Ti, V; Z = P, As, Sb, Si, Ge, Sn, Al, Ga, In) with 18 valence electrons are proposed and their bandgaps span a wide range of 0.10-1.39 eV, which have a great potential of applications in varied areas. Note that the bandgaps are predicted on the gradient-corrected Perdew-Burke-Ernzerhof functional, which underestimates the magnitude of bandgap. To obtain the accurate bandgaps, we recalculate them based on the Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional. Our results show that the nonlocal correction from the HSE06 functional mainly acts on the two lowest conduction bands. The variation in energy separation between these two bands dominates the relative increment of bandgap. More importantly, the band ordering is distinguished in the presence of HSE06 functional, where the dz2 orbital exhibits. When the lattice constant varies, such a band ordering can be inverted, similar to the case of topological insulators. In addition, we find an abnormal behavior of the bandgap related to the Pauling electronegativity difference between the X- and Z-sites, which arises from the delocalization of charge on the Y-site. We expect that our work can provide guidance to the study of bandgap based on the hybrid density functional theory in the half-Heusler semiconductors.

Elements in the transcriptional regulatory region flanking herpes simplex virus type 1 oriS stimulate origin function.

PubMed

Wong, S W; Schaffer, P A

1991-05-01

Like other DNA-containing viruses, the three origins of herpes simplex virus type 1 (HSV-1) DNA replication are flanked by sequences containing transcriptional regulatory elements. In a transient plasmid replication assay, deletion of sequences comprising the transcriptional regulatory elements of ICP4 and ICP22/47, which flank oriS, resulted in a greater than 80-fold decrease in origin function compared with a plasmid, pOS-822, which retains these sequences. In an effort to identify specific cis-acting elements responsible for this effect, we conducted systematic deletion analysis of the flanking region with plasmid pOS-822 and tested the resulting mutant plasmids for origin function. Stimulation by cis-acting elements was shown to be both distance and orientation dependent, as changes in either parameter resulted in a decrease in oriS function. Additional evidence for the stimulatory effect of flanking sequences on origin function was demonstrated by replacement of these sequences with the cytomegalovirus immediate-early promoter, resulting in nearly wild-type levels of oriS function. In competition experiments, cotransfection of cells with the test plasmid, pOS-822, and increasing molar concentrations of a competitor plasmid which contained the ICP4 and ICP22/47 transcriptional regulatory regions but lacked core origin sequences resulted in a significant reduction in the replication efficiency of pOS-822, demonstrating that factors which bind specifically to the oriS-flanking sequences are likely involved as auxiliary proteins in oriS function. Together, these studies demonstrate that trans-acting factors and the sites to which they bind play a critical role in the efficiency of HSV-1 DNA replication from oriS in transient-replication assays.

Homogenisation of sulphide inclusions within diamonds: A new approach to diamond inclusion geochemistry

NASA Astrophysics Data System (ADS)

McDonald, Iain; Hughes, Hannah S. R.; Butler, Ian B.; Harris, Jeffrey W.; Muir, Duncan

2017-11-01

Base metal sulphide (BMS) inclusions in diamonds provide a unique insight into the chalcophile and highly siderophile element composition of the mantle. Entombed within their diamond hosts, these provide a more robust (closed system) sample, from which to determine the trace element, Re-Os and S-isotopic compositions of the mantle than mantle xenoliths or orogenic peridotites, as they are shielded from alteration during ascent to the Earth's crust and subsequent surface weathering. However, at temperatures below 1100 °C some BMS inclusions undergo subsolidus re-equilibration from an original monosulphide solid solution (Mss) and this causes fractionation of the major and trace elements within the inclusions. Thus to study the subjects noted above, current techniques require the entire BMS inclusion to be extracted for analyses. Unfortunately, 'flaking' of inclusions during break-out is a frequent occurrence and hence the risk of accidentally under-sampling a portion of the BMS inclusion is inherent in current practices. This loss may have significant implications for Re-Os isotope analyses where incomplete sampling of a Re-rich phase, such as chalcopyrite that typically occurs at the outer margins of BMS inclusions, may induce significant bias in the Re-Os and 187Os/188Os measurements and resulting model and isochron ages. We have developed a method for the homogenisation of BMS inclusions in diamond prior to their break-out from the host stone. Diamonds are heated to 1100 °C and then quenched to chemically homogenise any sulphide inclusions for both major and trace elements. Using X-ray Computed Microtomography (μCT) we determine the shape and spatial setting of multiple inclusions within a host stone and crucially show that the volume of a BMS inclusion is the same both before and after homogenisation. We show that the homogenisation process significantly reduces the inherent variability of in situ analysis when compared with unhomogenised BMS, thereby widening the scope for multiple methods for quantitative analysis, even on 'flakes' of single BMS inclusions. Finally we show that the trace elements present in peridotite (P-type) and eclogitic (E-type) BMS are distinct, with P-type diamonds having systematically higher total platinum-group element (particularly Os, Ir, Ru) and Te and As concentrations. These distinctions suggest that the PGE and semi-metal budgets of mantle-derived partial melts will be significantly dependent upon the type(s) and proportions of sulphides present in the mantle source.

Self-esteem and counterfactual thinking.

PubMed

Roese, N J; Olson, J M

1993-07-01

Two studies examined the relation between self-esteem and counterfactual thinking (consideration of "might-have-been" alternatives to reality). Ss imagined themselves in scenarios with another actor that resulted in either success or failure. Ss then "undid" the outcome by altering events that preceded the outcome. Following success, high self-esteem (HSE) Ss were more likely than low self-esteem (LSE) Ss to mutate their own actions. Following failure, LSE Ss were more likely than HSE Ss to mutate their own actions. Also, the structure of counterfactuals was influenced by outcome valence but not by self-esteem: Subtractive structures (in which antecedents are removed) were elicited by success, whereas additive structures (in which antecedents are added) were elicited by failure. The importance of the self and individual differences in self-esteem to counterfactual thinking is discussed.

WNA's worldwide overview on front-end nuclear fuel cycle growth and health, safety and environmental issues.

PubMed

Saint-Pierre, Sylvain; Kidd, Steve

2011-01-01

This paper presents the WNA's worldwide nuclear industry overview on the anticipated growth of the front-end nuclear fuel cycle from uranium mining to conversion and enrichment, and on the related key health, safety, and environmental (HSE) issues and challenges. It also puts an emphasis on uranium mining in new producing countries with insufficiently developed regulatory regimes that pose greater HSE concerns. It introduces the new WNA policy on uranium mining: Sustaining Global Best Practices in Uranium Mining and Processing-Principles for Managing Radiation, Health and Safety and the Environment, which is an outgrowth of an International Atomic Energy Agency (IAEA) cooperation project that closely involved industry and governmental experts in uranium mining from around the world. Copyright © 2010 Health Physics Society

Seasonal influenza vaccine uptake in HSE-funded hospitals and nursing homes during the 2011/2012 influenza season.

PubMed

O'Lorcain, P; Cotter, S; Hickey, L; O'Flanagan, D; Corcoran, B; O'Meara, M

2014-03-01

Annual seasonal influenza vaccine is recommended for all health care workers (HCWs) in Ireland. For the 2011/2012 influenza season, information was collected on influenza vaccination uptake among HCWs employed in Health Service Executive (HSE)-funded hospitals (primarily acute) and of nursing homes (NHs) and also among NH long-term and short-term respite care residents. Forty-five hospitals (80%) and 120 NHs (75%) provided uptake data. Nationally, influenza vaccine uptake among hospital employed HCWs was estimated to be 18% and 14% among HCWs in NHs; in NHs vaccine uptake among long-term care residents was estimated to 88%. These findings highlight the continued low uptake among HCWs of all categories and demonstrate the need for sustained measures to improve uptake rates.

Osmium isotopes demonstrate distal transport of contaminated sediments in Chesapeake Bay

USGS Publications Warehouse

Helz, G.R.; Adelson, J.M.; Miller, C.V.; Cornwell, J.C.; Hill, J.M.; Horan, M.; Walker, R.J.

2000-01-01

Because the isotopic composition of anthropogenic Os is normally distinctive in comparison to continental crust and is precisely measurable, this platinum-group element is attractive as a tracer of transport pathways for contaminated sediments in estuaries. Evidence herein and elsewhere suggest that biomedical research institutions are the chief source of anthropogenic Os. In the Chesapeake Bay region, uncontaminated sediments bear a crustal 187Os/188Os signature of 0.73 ?? 0.10. Slightly higher 187Os/188Os ratios occur in Re-rich Coastal Plain deposits due to post- Miocene 187Re decay. The upper Susquehanna Basin yields sediments also with higher 187Os/188Os. Beginning in the late 1970s, this signal was overprinted by a low 187Os/188Os (anthropogenic) source in the lower Susquehanna Basin. In the vicinity of Baltimore, which is a major center of heavy industry as well as biomedical research, anthropogenic Os has been found only in sediments impacted by the principal wastewater treatment plant. Surprisingly, a mid-Bay site distant from anthropogenic sources contains the strongest anthropogenic Os signal in the data set, having received anthropogenic Os sporadically since the mid-20th Century. Transport of particles to this site overrode the northward flowing bottom currents. Finding anthropogenic Os at this site cautions that other particle-borne substances, including hazardous ones, could be dispersed broadly in this estuary.Because the isotopic composition of anthropogenic Os is normally distinctive in comparison to continental crust and is precisely measurable, this platinum-group element is attractive as a tracer of transport pathways for contaminated sediments in estuaries. Evidence herein and elsewhere suggest that biomedical research institutions are the chief source of anthropogenic Os. In the Chesapeake Bay region, uncontaminated sediments bear a crustal 187Os/188Os signature of 0.73 ?? 0.10. Slightly higher 187Os/188Os ratios occur in Re-rich Coastal Plain deposits due to post-Miocene 187Re decay. The upper Susquehanna Basin yields sediments also with higher 187Os/188Os. Beginning in the late 1970s, this signal was overprinted by a low 187Os/188Os (anthropogenic) source in the lower Susquehanna Basin. In the vicinity of Baltimore, which is a major center of heavy industry as well as biomedical research, anthropogenic Os has been found only in sediments impacted by the principal wastewater treatment plant. Surprisingly, a mid-Bay site distant from anthropogenic sources contains the strongest anthropogenic Os signal in the data set, having received anthropogenic Os sporadically since the mid-20th Century. Transport of particles to this site overrode the northward flowing bottom currents. Finding anthropogenic Os at this site cautions that other particle-borne substances, including hazardous ones, could be dispersed broadly in this estuary.

Platinum-group elements (PGE) and Rhenium in Marine Sediments across the Cretaceous-Tertiary Boundary: Constraints on Re-PGE Transport in the Marine Environment

NASA Technical Reports Server (NTRS)

Lee, Cin-Ty Aeolus; Wasserburg, Gerald J.; Kyte, Frank T.

2003-01-01

The nature of Re-platinum-group element (PGE; Pt, Pd, Ir, Os, Ru) transport in the marine environment was investigated by means of marine sediments at and across the Cretaceous-Tertiary boundary (KTB) at two hemipelagic sites in Europe and two pelagic sites in the North and South Pacific. A traverse across the KTB in the South Pacific pelagic clay core found elevated levels of Re, Pt, Ir, Os, and Ru, each of which is approximately symmetrically distributed over a distance of approx. 1.8 m across the KTB. The Re-PGE abundance patterns are fractionated from chondritic relative abundances: Ru, Pt, Pd, and Re contents are slightly subchondritic relative to Ir, and Os is depleted by approx. 95% relative to chondritic Ir proportions. A similar depletion in Os (approx. 90%) was found in a sample of the pelagic KTB in the North Pacific, but it is enriched in Ru, Pt, Pd, and Re relative to Ir. The two hemipelagic KTB clays have near-chondritic abundance patterns. The approx. 1.8-m-wide Re-PGE peak in the pelagic South Pacific section cannot be reconciled with the fallout of a single impactor, indicating that postdepositional redistribution has occurred. The elemental profiles appear to fit diffusion profiles, although bioturbation could have also played a role. If diffusion had occurred over approx. 65 Ma, the effective diffusivities are approx. 10(exp -13)sq cm/s, much smaller than that of soluble cations in pore waters (approx. 10(exp -5) sq cm/s). The coupling of Re and the PGEs during redistribution indicates that postdepositional processes did not significantly fractionate their relative abundances. If redistribution was caused by diffusion, then the effective diffusivities are the same. Fractionation of Os from Ir during the KTB interval must therefore have occurred during aqueous transport in the marine environment. Distinctly subchondritic Os/Ir ratios throughout the Cenozoic in the South Pacific core further suggest that fractionation of Os from Ir in the marine environment is a general process throughout geologic time because most of the inputs of Os and Ir into the ocean have OsAr ratios greater than or = 1. Mass balance calculations show that Os and Re burial fluxes in pelagic sediments account for only a small fraction of the riverine Os (less than 10%) and Re (less than 0.1%) inputs into the oceans. In contrast, burial of Ir in pelagic sediments is similar to the riverine Ir input, indicating that pelagic sediments are a much larger repository for Ir than for Os and Re. If all of the missing Os and Re is assumed to reside in anoxic sediments in oceanic margins, the calculated burial fluxes in anoxic sediments are similar to observed burial fluxes. However, putting all of the missing Os and Re into estuarine sediments would require high concentrations to balance the riverine input and would also fail to explain the depletion of Os at pelagic KTB sites, where at most approx. 25% of the K-T impactor's Os could have passed through estuaries. If Os is preferentially sequestered in anoxic marine environments, it follows that the OsAr ratio of pelagic sediments should be sensitive to changes in the rates of anoxic sediment deposition. There is thus a clear fractionation of Os and Re from Ir in precipitation out of sea water in pelagic sections. Accordingly, it is inferred here that Re and Os are removed from sea water in anoxic marine depositional regimes.

Major and Trace Element Geochemistry and Os Isotopic Compositions of Komatiites From Dundonald Beach, Abitibi Greenstone Belt, Canada

NASA Astrophysics Data System (ADS)

Gangopadhyay, A.; Walker, R. J.; Sproule, R. A.; Lesher, C.

2003-12-01

We have examined the major and trace elements, and Os isotopic compositions of a suite of cumulate and spinifex textured komatiitic rocks from the Dundonald Beach area, part of the ˜2.7 Ga Abitibi greenstone Belt, Ontario, Canada. This suite of rocks forms a series from peridotitic komatiites (MgO ˜ 42 wt.% on a volatile-free basis) to komatiitic basalts (MgO ˜8 wt.%). Based on major element oxide ratios (e.g. Al2O3/TiO2 ˜21-26 and CaO/Al2O3 typically <= 1) and unfractionated HREE characteristics (e.g. (Gd/Yb)N ˜0.9-1.1), these rocks are similar to the spatially associated Al-undepleted komatiites from Alexo and Munro Townships. Also, these rocks are strongly LREE-depleted ((La/Sm)N = 0.41-0.67; (Ce/Yb)N = 0.41-0.70)) and have variable total REE (4-22 ppm). A strong negative correlation between Mg# and total REEs suggests that the REE patterns of these rocks are primary features of their mantle source. The Re-Os isotope results for whole-rock komatiites and chromite separates from a single flow yield a model 3 isochron age of 2606 +/- 55 Ma. This age is slightly younger ( ˜50 Ma) compared to the U-Pb zircon ages of the associated volcanics reported from the presumed extension of the same Kidd-Munro assemblage in Alexo and Munro Townships. The initial 187Os/188Os ratio (0.1090 +/- 0.0019) obtained from the regression is essentially chondritic (γ Os(T) = -0.2 +/- 1.7). The peridotitic komatiites have the highest Os concentrations and low 187Re/188Os ratios (up to ˜4.2 ppb and < 0.5, respectively) among the whole rocks, whereas the komatiitic basalts have relatively low Os concentrations ( ˜0.3 ppb) and high 187Re/188Os ratios ( ˜3.1-11.9). For these komatiites, Os was compatible with the mantle residue (DOsmantle-melt ˜7.6), whereas Re was moderately incompatible (DRe ˜0.6), typical of most komatiitic magmas. The absence of a strong correlation between Os and Ni concentrations in the whole-rocks suggests that the distribution of Os in these rocks is not primarily controlled by fractionation of olivine. The apparent DReol+chmt/liq. ( ˜0.7), on the other hand, suggests that Re was moderately incompatible in olivine and/or chromite during the differentiation of komatiitic magmas. A chondritic initial Os isotopic composition for the mantle source for these komatiites is consistent with that previously reported for the komatiites from Alexo and Munro Townships. Our Os isotopic results for Dundonald komatiites, combined with those reported for Alexo and Pyke Hill komatiites, therefore, suggest that a major portion of the ˜2.7 Ga mantle source for the komatiites in the Abitibi greenstone belt was dominated by Os with chondritic isotopic compositions. Also, the LREE-depleted, yet chondritic Os isotopic composition for the mantle source of these komatiites is indistinguishable from the projected chondritic composition of the contemporaneous depleted convective upper mantle.

Airborne isocyanate exposures in the collision repair industry and a comparison to occupational exposure limits.

PubMed

Reeb-Whitaker, Carolyn; Whittaker, Stephen G; Ceballos, Diana M; Weiland, Elisa C; Flack, Sheila L; Fent, Kenneth W; Thomasen, Jennifer M; Trelles Gaines, Linda G; Nylander-French, Leena A

2012-01-01

Isocyanate exposure was evaluated in 33 spray painters from 25 Washington State autobody shops. Personal breathing zone samples (n = 228) were analyzed for isophorone diisocyanate (IPDI) monomer, 1,6-hexamethylene diisocyanate (HDI) monomer, IPDI polyisocyanate, and three polyisocyanate forms of HDI. The objective was to describe exposures to isocyanates while spray painting, compare them with short-term exposure limits (STELs), and describe the isocyanate composition in the samples. The composition of polyisocyanates (IPDI and HDI) in the samples varied greatly, with maximum amounts ranging from up to 58% for HDI biuret to 96% for HDI isocyanurate. There was a significant inverse relationship between the percentage composition of HDI isocyanurate to IPDI and to HDI uretdione. Two 15-min STELs were compared: (1) Oregon's Occupational Safety and Health Administration (OR-OSHA) STEL of 1000 μg/m(3) for HDI polyisocyanate, and (2) the United Kingdom's Health and Safety Executive (UK-HSE) STEL of 70 μg NCO/m(3) for all isocyanates. Eighty percent of samples containing HDI polyisocyanate exceeded the OR-OSHA STEL while 98% of samples exceeded the UK-HSE STEL. The majority of painters (67%) wore half-face air-purifying respirators while spray painting. Using the OR-OSHA and the UK-HSE STELs as benchmarks, 21% and 67% of painters, respectively, had at least one exposure that exceeded the respirator's OSHA-assigned protection factor. A critical review of the STELs revealed the following limitations: (1) the OR-OSHA STEL does not include all polyisocyanates, and (2) the UK-HSE STEL is derived from monomeric isocyanates, whereas the species present in typical spray coatings are polyisocyanates. In conclusion, the variable mixtures of isocyanates used by autobody painters suggest that an occupational exposure limit is required that includes all polyisocyanates. Despite the limitations of the STELs, we determined that a respirator with an assigned protection factor of 25 or greater is required to protect against isocyanate exposures during spray painting. Consequently, half-face air-purifying respirators, which are most commonly used and have an assigned protection factor of 10, do not afford adequate respiratory protection.

Electronic structure and metallization of cubic GdH{sub 3} under pressure: Ab initio many-body GW calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kong, Bo, E-mail: kong79@yeah.net, E-mail: yachao.zhang@pku.edu.cn; Guizhou Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang 550018; Zhang, Yachao, E-mail: kong79@yeah.net, E-mail: yachao.zhang@pku.edu.cn

The electronic structures of the cubic GdH{sub 3} are extensively investigated using the ab initio many-body GW calculations treating the Gd 4f electrons either in the core (4f-core) or in the valence states (4f-val). Different degrees of quasiparticle (QP) self-consistent calculations with the different starting points are used to correct the failures of the GGA/GGA + U/HSE03 calculations. In the 4f-core case, GGA + G{sub 0}W{sub 0} calculations give a fundamental band gap of 1.72 eV, while GGA+ GW{sub 0} or GGA + GW calculations present a larger band gap. In the 4f-val case, the nonlocal exchange-correlation (xc) functional HSE03 can account much better for the strong localizationmore » of the 4f states than the semilocal or Hubbard U corrected xc functional in the Kohn–Sham equation. We show that the fundamental gap of the antiferromagnetic (AFM) or ferromagnetic (FM) GdH{sub 3} can be opened up by solving the QP equation with improved starting point of eigenvalues and wave functions given by HSE03. The HSE03 + G{sub 0}W{sub 0} calculations present a fundamental band gap of 2.73 eV in the AFM configuration, and the results of the corresponding GW{sub 0} and GW calculations are 2.89 and 3.03 eV, respectively. In general, for the cubic structure, the fundamental gap from G{sub 0}W{sub 0} calculations in the 4f-core case is the closest to the real result. By G{sub 0}W{sub 0} calculations in the 4f-core case, we find that H or Gd defects can strongly affect the band structure, especially the H defects. We explain the mechanism in terms of the possible electron correlation on the hydrogen site. Under compression, the insulator-to-metal transition in the cubic GdH{sub 3} occurs around 40 GPa, which might be a satisfied prediction.« less

Passively Administered Pooled Human Immunoglobulins Exert IL-10 Dependent Anti-Inflammatory Effects that Protect against Fatal HSV Encephalitis

PubMed Central

Ramakrishna, Chandran; Newo, Alain N. S.; Shen, Yueh-Wei; Cantin, Edouard

2011-01-01

HSV-1 is the leading cause of sporadic encephalitis in humans. HSV infection of susceptible 129S6 mice results in fatal encephalitis (HSE) caused by massive inflammatory brainstem lesions comprising monocytes and neutrophils. During infection with pathogenic microorganisms or autoimmune disease, IgGs induce proinflammatory responses and recruit innate effector cells. In contrast, high dose intravenous immunoglobulins (IVIG) are an effective treatment for various autoimmune and inflammatory diseases because of potent anti-inflammatory effects stemming in part from sialylated IgGs (sIgG) present at 1–3% in IVIG. We investigated the ability of IVIG to prevent fatal HSE when given 24 h post infection. We discovered a novel anti-inflammatory pathway mediated by low-dose IVIG that protected 129S6 mice from fatal HSE by modulating CNS inflammation independently of HSV specific antibodies or sIgG. IVIG suppressed CNS infiltration by pathogenic CD11b+ Ly6Chigh monocytes and inhibited their spontaneous degranulation in vitro. FcγRIIb expression was required for IVIG mediated suppression of CNS infiltration by CD45+ Ly6Clow monocytes but not for inhibiting development of Ly6Chigh monocytes. IVIG increased accumulation of T cells in the CNS, and the non-sIgG fraction induced a dramatic expansion of FoxP3+ CD4+ T regulatory cells (Tregs) and FoxP3− ICOS+ CD4+ T cells in peripheral lymphoid organs. Tregs purified from HSV infected IVIG treated, but not control, mice protected adoptively transferred mice from fatal HSE. IL-10, produced by the ICOS+ CD4+ T cells that accumulated in the CNS of IVIG treated, but not control mice, was essential for induction of protective anti-inflammatory responses. Our results significantly enhance understanding of IVIG's anti-inflammatory and immunomodulatory capabilities by revealing a novel sIgG independent anti-inflammatory pathway responsible for induction of regulatory T cells that secrete the immunosuppressive cytokine IL-10 and further reveal the therapeutic potential of IVIG for treating viral induced inflammatory diseases. PMID:21655109

Sulfated caffeic acid dehydropolymer attenuates elastase and cigarette smoke extract-induced emphysema in rats: sustained activity and a need of pulmonary delivery.

PubMed

Saluja, Bhawana; Li, Hua; Desai, Umesh R; Voelkel, Norbert F; Sakagami, Masahiro

2014-08-01

Although emphysema destroys alveolar structures progressively and causes death eventually, no drug has been discovered to prevent, intervene, and/or resolve this life-threatening disease. We recently reported that sulfated caffeic acid dehydropolymer CDSO3 is a novel potent triple-action inhibitor of elastolysis, oxidation, and inflammation in vitro, and therefore, a potential anti-emphysema agent. However, the in vivo therapeutic potency, duration and mode of actions, and effective route remain to be demonstrated. Emphysema was induced in rats with human sputum elastase (HSE) combined with cigarette smoke extract (CSE). CDSO3 at 5, 30, or 100 μg/kg was dosed to the lung or injected subcutaneously at 2, 6, or 24 h before or 1 or 24 h or 1 week after the HSE/CSE instillation. At 1 h or 48 h or on day 21-22 or day 28, lungs were examined for airway-to-blood injurious barrier damage; their elastolytic, oxidative, and inflammatory activities; lung luminal leukocytes infiltration; functional treadmill exercise endurance; and/or morphological airspace enlargement. CDSO3, when dosed to the lung at 30 or 100 μg/kg, but not via systemic subcutaneous injection, significantly (43-93 %) attenuated HSE/CSE-induced (1) barrier damage measured by luminal hemorrhage and protein leak; (2) elastolytic, oxidative, and inflammatory activities measured with elastase, reduced glutathione, and TNFα levels, respectively; (3) luminal neutrophil infiltration and tissue myeloperoxidase activity; (4) functional impairment of exercise endurance; and (5) airspace enlargement, in both preventive and interventional dosing protocols. Notably, the effects were shown to last for 24 h at the greater 100-μg/kg dose, and the 1-week-delayed administration was also capable of attenuating the development of emphysema. CDSO3 is a novel, potent, long-acting, nonpeptidic macromolecule that inhibits HSE/CSE-induced elastolysis, oxidation, and inflammation in the lung and thereby attenuates the development of emphysema in rats, in both preventive and interventional manners, when administered locally to the lung.

Complex anthropogenic sources of platinum group elements in aerosols on Cape Cod, USA.

PubMed

Sen, Indra S; Peucker-Ehrenbrink, Bernhard; Geboy, Nicholas

2013-09-17

Platinum group elements (PGE) of anthropogenic origin have been reported in rainwater, snow, roadside soil and vegetation, industrial waste, and urban airborne particles around the world. As recent studies have shown that PGE are bioavailable in the environment and pose health risks at chronic levels, the extent of PGE pollution is of global concern. In this study, we report PGE concentrations and osmium isotope ((187)Os/(188)Os) ratios of airborne particles (particulate matter, PM10) collected in Woods Hole, a small coastal village on Cape Cod, Massachusetts, U.S.A. The sampling site is more than 100 km away from the nearest urban centers (Boston, Providence) and has no large industrial emission center within a 30 km radius. The study reveals that, although PGE concentrations in rural airborne particulate matter are orders of magnitude lower than in urban aerosols, 69% of the total osmium is of anthropogenic origin. Anthropogenic PGE signatures in airborne particles are thus not restricted to large cities with high traffic flows and substantial industries; they can also be found in rural environments. We further conclude that the combination of Pt/Rh concentration ratios and (187)Os/(188)Os composition can be used to trace PGE sources. The Pt/Rh and (187)Os/(188)Os composition of Woods Hole aerosols indicate that the anthropogenic PGE fraction is primarily sourced from ore smelting processes, with possible minor contributions from fossil fuel burning and automobile catalyst-derived materials. Our results further substantiate the use of (187)Os/(188)Os in source apportionment studies on continental scales.

Investigation of Hard Boron Rich Solids: Osmium Diboride and β-Rhombohedral Boron

NASA Astrophysics Data System (ADS)

Hebbache, M.; Živković, D.

Recently, we succeeded in synthesizing three osmium borides, i.e., OsB1.1, Os2B3 and OsB2. Up to date, almost nothing is known about the physical properties of these materials. Microhardness measurements show that OsB2 is extremely hard. Ab initio calculations show that it is due to formation of covalent bonds between boron atoms. OsB2 is also a low compressibility material. It can be used for hard coatings. The β-rhombohedral polymorph of boron is the second hardest elemental crystal (H ≈ 33 GPa). It is also very light and a p-type semiconductor. In early 1970s, it has been shown that the doping of boron with 3d transition elements enhances its hardness by about 25%. We predict that, in general, heavily doped samples MBx, with x ≤ 31 or equivalently a dopant concentration larger than 3.2 at.%, should be ultrahard, i.e., H > 43 GPa. The relevant dopants M are Al, Cu, Sc, Mn, Mg and Li. In addition to these properties, boron-rich materials have a very low volatility, a high chemical inertness and high melting point. They are suitable for applications under extreme conditions and thermoelectric equipment.

Testing the Younger Dryas impact hypothesis with platinum-group elements (PGE), Re, and Os isotopes in sediments from Hall's Cave and Freidken Archaeological site, Texas

NASA Astrophysics Data System (ADS)

Sun, N.; Brandon, A. D.; Forman, S. L.

2017-12-01

The Younger Dryas impact hypothesis suggests that extraterrestrial (ET) object(s) hit and exploded over North America 12,900 years ago and triggered the onset of Younger Dryas (YD) cooling and widespread megafaunal extinctions and the demise of the Clovis archeological culture. Supporting signatures such as concentrated carbon spherules and enlogaes, magnetic grains and spherules, nanodiamonds, and Ir-enrichment have been reported, but over time their lack of reproducibility of results at different locations have brought into question the impact hypothesis. Among the impact signatures investigated by previous studies, only few researchers included Re and platinum group element (PGE: Os, Ir, Ru, Rh, Pt, and Pd) characteristic concentrations, and 187Os/188Os ratios for ET mixing in terrestrial materials. Less than 1% of ET materials can provide enriched PGE concentrations, such that PGE are a sensitive tool to identify ET input in terrestrial materials. Because of the large difference between chondritic and continental crust 187Os/188Os ratios, 0.127 and >1.4, respectively, the 187Os/188Os ratios are also highly sensitive indicators of an extraterrestrial component in terrestrial and marine sediments. In this study, we examine sediments associated with the YD from two reported sites in North America, Hall's Cave and the Freidken Archaeological site in Central Texas, using the PGE and Re geochemical approach to test the evidence of the extraterrestrial projectiles during Younger Dryas period. Our current data show at Hall's Cave the PGE concentrations and patterns do not confirm the presence of an elevated meteoritic contribution. However, the 187Os/188Os depth profile shows a sudden 187Os/188Os decrease from 2.28 2.45 to 1.64 at the YD boundary layer, consistent with an increase in material derived from ET projectiles with chondritic 187Os/188Os ratios contaminating the Earth surface at the time of the YD extinction. Additional samples from the YD boundary at the Freidken site will also be presented in order to determine if a change in the 187Os/188Os signature occurs here as well. The combination of data across the YD boundary in both locales allows for a better evaluation of the possible causes for the YD extinction.

Platinum-group element abundances and Re-Os isotopic systematics of the upper continental crust through time: Evidence from glacial diamictites

NASA Astrophysics Data System (ADS)

Chen, Kang; Walker, Richard J.; Rudnick, Roberta L.; Gao, Shan; Gaschnig, Richard M.; Puchtel, Igor S.; Tang, Ming; Hu, Zhao-Chu

2016-10-01

The fine-grained matrix of glacial diamictites, deposited periodically by continental ice sheets over much of Earth history, provides insights into the average composition and chemical evolution of the upper continental crust (UCC) (Gaschnig et al., 2016, and references therein). The concentrations of platinum-group elements (PGEs, including Os, Ir, Ru, Pt and Pd) and the geochemically related Re, as well as 187Re/188Os and 187Os/188Os ratios, are reported here for globally-distributed glacial diamictites that were deposited during the Mesoarchean, Paleoproterozoic, Neoproterozoic and Paleozoic eras. The medians and averages of PGE concentrations of these diamictite composites decrease from the Mesoarchean to the Neoproterozoic, mimicking decreases in the concentrations of first-row transition elements (Sc, V, Cr, Co and Ni). By contrast, Re concentrations are highly variable with no discernable trend, owing to its high solubility. Assuming these diamictites are representative of average UCC through time, the new data are fully consistent with the previous inference that the Archean UCC contained a greater proportion of mafic-ultramafic rocks relative to younger UCC. Linear regressions of PGEs versus Cr and Ni concentrations in all the diamictite composites from the four time periods are used to estimate the following concentrations of the PGEs in the present-day UCC: 0.059 ± 0.016 ng/g Os, 0.036 ± 0.008 ng/g Ir, 0.079 ± 0.026 ng/g Ru, 0.80 ± 0.22 ng/g Pt and 0.80 ± 0.26 ng/g Pd (2σ of 10,000 bootstrapping regression results). These PGE estimates are slightly higher than the estimates obtained from loess samples. We suggest this probably results from loess preferentially sampling younger UCC rocks that have lower PGE concentrations, or PGEs being fractionated during loess formation. A Re concentration of 0.25 ± 0.12 ng/g (2σ) is obtained from a regression of Re versus Mo. From this, time-integrated 187Re/188Os and 187Os/188Os ratios for the UCC are calculated, assuming an average UCC residence duration of ∼2.0 Ga, yielding ratios of 20 ± 12 and 0.80 ± 0.38 (2σ), respectively.

High resistivity in undoped CdTe: carrier compensation of Te antisites and Cd vacancies

NASA Astrophysics Data System (ADS)

Lindström, A.; Mirbt, S.; Sanyal, B.; Klintenberg, M.

2016-01-01

In this paper, we focus on the high resistivity of intentionally undoped CdTe, where the most prevalent defects are Cd vacancies and Te antisites. Our calculated formation energies lead to the conclusion that the Fermi energy of undoped CdTe is at midgap due to carrier compensation of Te antisites and Cd vacancies, which explains the experimentally observed high resistivity. We use density functional theory with the hybrid functional of Heyd, Scuseria and Ernzerhof (HSE06) and show that the proper description of the native defects in general fails using the local density approximation (LDA) instead of HSE06. We conclude that LDA is insufficient to understand the high resistivity of undoped CdTe. We calculate the neutral and double acceptor state of the Te antisite to be intrinsic DX-centers.

The Type I Interferon Response and Age-Dependent Susceptibility to Herpes Simplex Virus Infection.

PubMed

Giraldo, Daniel; Wilcox, Douglas R; Longnecker, Richard

2017-05-01

Herpes simplex virus type 1 (HSV-1) is a highly prevalent human neurotropic pathogen. HSV-1 infection is associated with a variety of diseases ranging from benign orolabial lesions to more serious and even life-threatening conditions such as herpes simplex keratitis and herpes simplex encephalitis (HSE). HSE is a rare occurrence among healthy adult individuals, but newborns are a particularly susceptible population. Type I IFN signaling has been identified as a crucial component of the innate immune response to the control of HSV-1 infection. In this study, we review the contribution of the type I IFN response to controlling HSV-1 infection, and differences in the early host response between adults and newborns that may contribute to the increased susceptibility to infection and central nervous system disease in newborns.

Density Functional Theory and Beyond for Band-Gap Screening: Performance for Transition-Metal Oxides and Dichalcogenides.

PubMed

Li, Wenqing; Walther, Christian F J; Kuc, Agnieszka; Heine, Thomas

2013-07-09

The performance of a wide variety of commonly used density functionals, as well as two screened hybrid functionals (HSE06 and TB-mBJ), on predicting electronic structures of a large class of en vogue materials, such as metal oxides, chalcogenides, and nitrides, is discussed in terms of band gaps, band structures, and projected electronic densities of states. Contrary to GGA, hybrid functionals and GGA+U, both HSE06 and TB-mBJ are able to predict band gaps with an appreciable accuracy of 25% and thus allow the screening of various classes of transition-metal-based compounds, i.e., mixed or doped materials, at modest computational cost. The calculated electronic structures are largely unaffected by the choice of basis functions and software implementation, however, might be subject to the treatment of the core electrons.

Why the Heyd-Scuseria-Ernzerhof hybrid functional description of VO2 phases is not correct

NASA Astrophysics Data System (ADS)

Grau-Crespo, Ricardo; Wang, Hao; Schwingenschlögl, Udo

2012-08-01

In contrast with recent claims that the Heyd-Scuseria-Ernzerhof (HSE) screened hybrid functional can provide a good description of the electronic and magnetic structures of VO2 phases [Eyert, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.016401 107, 016401 (2011)], we show here that the HSE lowest-energy solutions for both the low-temperature monoclinic (M1) phase and the high-temperature rutile (R) phase, which are obtained upon inclusion of spin polarization, are at odds with experimental observations. For the M1 phase the ground state is (but should not be) magnetic, while the ground state of the R phase, which is also spin polarized, is not (but should be) metallic. The energy difference between the low-temperature and high-temperature phases has strong discrepancies with the experimental latent heat.

Health, Safety, and Environment Division

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wade, C

1992-01-01

The primary responsibility of the Health, Safety, and Environmental (HSE) Division at the Los Alamos National Laboratory is to provide comprehensive occupational health and safety programs, waste processing, and environmental protection. These activities are designed to protect the worker, the public, and the environment. Meeting these responsibilities requires expertise in many disciplines, including radiation protection, industrial hygiene, safety, occupational medicine, environmental science and engineering, analytical chemistry, epidemiology, and waste management. New and challenging health, safety, and environmental problems occasionally arise from the diverse research and development work of the Laboratory, and research programs in HSE Division often stem from thesemore » applied needs. These programs continue but are also extended, as needed, to study specific problems for the Department of Energy. The results of these programs help develop better practices in occupational health and safety, radiation protection, and environmental science.« less

Screened Hybrid and DFT + U Studies of the Structural, Electronic, and Optical Properties of U3O8

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wen, Xiaodong; Martin, Richard L.; Scuseria, Gustavo E.

2012-11-26

A systematic comparison of the structures and electronic and optical properties of U3O8 in the c2mm, P¯62m, and P21/m structures (the α, β, and γ phases, respectively) is performed using density functional theory + U (PBE + U) and the Heyd–Scuseria–Ernzerhof screened hybrid functional (HSE). The relationship between the semiconducting C2mm phase of U3O8 and the high temperature, metallic P¯62m phase is explored in more detail. Our calculated results show that the HSE functional gives a better description of the electronic and optical properties when compared with available experimental data for the α and β phases, but neither approach doesmore » particularly well for the high pressure γ phase.« less

Synthesis, crystal structure determination, thermal and magnetic properties of the new Cu0.73Ni0.27(HSeO3)2 compound

NASA Astrophysics Data System (ADS)

Hentech, I.; Zehani, K.; Kabadou, A.; Ben Salah, A.; Loukil, M.; Bessais, L.

2017-01-01

A novel three-dimensional Cu0.73Ni0.27(HSeO3)2 compound was prepared from an aqueous solution. This compound crystallizes in the monoclinic system with P21/n space group and with the following cell parameters: a=6.4379(3) Å; b=7.3555(3) Å; c=5.7522(3) Å; β=93.4341(1)°; V=271.90(2) Å3 and Z=2. The reported material has been structurally characterized by X-ray powder diffraction and confirmed by scanning electron microscope and energy dispersive spectroscopy (MEB/EDS) analysis. The copper/nickel atom is surrounded by an octahedron coordination of oxygen atoms from sex hydrogenoselenites anions. The presence of (HSeO3)- has been further confirmed by IR spectroscopy and this compound exhibits a phase transition at 356 K, this transition has been detected by differential scanning calorimetry and TG-DTA measurement. The magnetic property of this material was determined. The ferromagnetic ordering is further confirmed by the magnetic field dependence of the magnetization (Hysteresis loop) at 10 K. The substitution of Cu by Ni induces a ferro-paramagnetic transition at T=31 K. Field cooled (FC) and Zero field cooled (ZFC) magnetization measurements under an applied field of 100 Oe in the temperature range of 10-300 K were performed. These measurements have been resulted the blocking temperature (TB) at around 25 K.

Uptake and quality of health surveillance for noise and hand-arm vibration.

PubMed

Poole, K; Mason, H J; Harris-Roberts, J

2011-08-01

Health surveillance (HS) is required for employees if noise or hand-arm vibration (HAV) exposures are likely to be above exposure action levels. The extent to which employers comply with Health and Safety Executive (HSE) regulations is unclear. To establish the uptake and quality of HS for noise and HAV in high-risk industries. A cross-sectional telephone-based questionnaire study involving employers in high-risk industries for noise or HAV. A total of 246 and 386 interviews were completed for noise and HAV, respectively. The uptake of HS in the cohorts was 17 and 10%, respectively. Selection of those companies thought to have 'higher risk' increased the uptake to 25 and 18%, respectively. The proportion of companies carrying out HS was strongly related to the size of the company, with smaller companies less likely to provide this for their employees. A large proportion of companies that reported having HS in place had formal procedures for managing exposed workers (90 and 83% for noise and HAV, respectively), received feedback on individual workers (81 and 80%) and some reported that they used this information to inform their risk management process (58 and 63%). The frequency of HS for HAV was in line with that suggested in HSE guidance in 70% of cases, however, for noise, it was often utilized more frequently. While many of the companies appear to be following HSE guidance, there is a significant number that are not. Further initiatives that engage with smaller companies may help increase HS provision.

Psychometric Properties of a 36-Item Version of the “Stress Management Competency Indicator Tool”

PubMed Central

Toderi, Stefano; Sarchielli, Guido

2016-01-01

The development of supervisors’ behaviours has been proposed as an innovative approach for the reduction of employees’ work stress. The UK Health and Safety Executive (HSE) developed the “Stress Management Competency Indicator Tool” (SMCIT), designed to be used within a learning and development intervention. However, its psychometric properties have never been evaluated, and the length of the questionnaire (66 items) limits its practical applicability. We developed a brief 36-item version of the questionnaire, assessed its psychometric properties and studied the relationship with the employees’ psychosocial work environment. 353 employees filled in the brief SMCIT and the “Stress Management Indicator Tool”. The latter is a self-report questionnaire developed by the UK HSE, measuring workers’ perceptions of seven dimensions of the psychosocial work environment that if not properly managed can lead to harm. Data were analysed with structural equation modelling and multiple regressions. The results confirmed the factorial structure of the brief SMCIT questionnaire and mainly supported the convergent validity and internal consistency of the scales. Furthermore, with few exceptions, the relations hypothesized between supervisors’ competencies and the psychosocial work environment were confirmed, supporting the criterion validity of the revised questionnaire and the UK HSE framework. We conclude that the brief 36-item version of the SMCIT represents an important step toward the development of interventions directed at supervisors and we discuss the practical implications for work stress prevention. PMID:27827940

Human TRAF3 adaptor molecule deficiency leads to impaired Toll-like receptor 3 response and susceptibility to herpes simplex encephalitis

PubMed Central

de Diego, Rebeca Pérez; Sancho-Shimizu, Vanessa; Lorenzo, Lazaro; Puel, Anne; Plancoulaine, Sabine; Picard, Capucine; Herman, Melina; Cardon, Annabelle; Durandy, Anne; Bustamante, Jacinta; Vallabhapurapu, Sivakumar; Bravo, Jerónimo; Warnatz, Klaus; Chaix, Yves; Cascarrigny, Françoise; Lebon, Pierre; Rozenberg, Flore; Karin, Michael; Tardieu, Marc; Al-Muhsen, Saleh; Jouanguy, Emmanuelle; Zhang, Shen-Ying; Abel, Laurent; Casanova, Jean-Laurent

2010-01-01

Tumor necrosis factor (TNF) receptor-associated factor 3 (TRAF3) functions downstream of multiple receptors that induce interferon-α (IFN-α), IFN–β and IFN-λ production, including Toll-like receptor 3 (TLR3), which is deficient in some patients with herpes simplex virus-1 encephalitis (HSE). Mice lacking TRAF3 die in the neonatal period, preventing direct investigation of the role of TRAF3 in immune responses and host defenses in vivo. Here we reported the autosomal dominant, human TRAF3 deficiency in a young adult with a history of HSE in childhood. The TRAF3 mutant allele was a loss-of-expression, loss-of-function, dominant-negative phenotype, and was associated with impaired, but not abolished TRAF3-dependent responses upon stimulation of both TNF receptors and receptors that induce IFN production. TRAF3 deficiency was associated with a clinical phenotype limited to HSE resulting from the impairment of TLR3-dependent induction of IFN. Thus, TLR3-mediated immunity against primary infection by HSV-1 in the central nervous system is critically dependent on TRAF3. Highlight sentence Autosomal dominant TRAF3 deficiency is a genetic etiology of herpes simplex encephalitis. Highlight sentence R118W TRAF3 allele is loss-of-function, loss-of-expression, and dominant-negative. Highlight sentence Human TRAF3 deficiency impairs the TLR3-dependent induction of anti-viral interferons. PMID:20832341

Empirical optimization of DFT  +  U and HSE for the band structure of ZnO.

PubMed

Bashyal, Keshab; Pyles, Christopher K; Afroosheh, Sajjad; Lamichhane, Aneer; Zayak, Alexey T

2018-02-14

ZnO is a well-known wide band gap semiconductor with promising potential for applications in optoelectronics, transparent electronics, and spintronics. Computational simulations based on the density functional theory (DFT) play an important role in the research of ZnO, but the standard functionals, like Perdew-Burke-Erzenhof, result in largely underestimated values of the band gap and the binding energies of the Zn 3d electrons. Methods like DFT  +  U and hybrid functionals are meant to remedy the weaknesses of plain DFT. However, both methods are not parameter-free. Direct comparison with experimental data is the best way to optimize the computational parameters. X-ray photoemission spectroscopy (XPS) is commonly considered as a benchmark for the computed electronic densities of states. In this work, both DFT  +  U and HSE methods were parametrized to fit almost exactly the binding energies of electrons in ZnO obtained by XPS. The optimized parameterizations of DFT  +  U and HSE lead to significantly worse results in reproducing the ion-clamped static dielectric tensor, compared to standard high-level calculations, including GW, which in turn yield a perfect match for the dielectric tensor. The failure of our XPS-based optimization reveals the fact that XPS does not report the ground state electronic structure for ZnO and should not be used for benchmarking ground state electronic structure calculations.

The HSE management system in practice-implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Primrose, M.J.; Bentley, P.D.; Sykes, R.M.

1996-11-01

This paper sets out the necessary strategic issues that must be dealt with when setting up a management system for HSE. It touches on the setting of objectives using a form of risk matrix and the establishment of corporate risk tolerability levels. Such issue management is vital but can be seen as yet another corporate HQ initiative. It must therefore be linked, and made relevant to those in middle management tasked with implementing the system and also to those at risk {open_quote}at the sharp end{close_quote} of the business. Setting acceptance criteria is aimed at demonstrating a necessary and sufficient levelmore » of control or coverage for those hazards considered as being within the objective setting of the Safety or HSE Case. Critical risk areas addressed via the Safety Case, within Shell companies at least, must show how this coverage is extended to critical health and environmental issues. Methods of achieving this are various ranging from specific Case deliverables (like the Hazard Register and Accountability Matrices) through to the incorporation of topics from the hazard analysis in toolbox talks and meetings. Risk analysis techniques are increasingly seen as complementary rather than separate with environmental assessments, health risk assessment sand safety risk analyses taking place together and results being considered jointly. The paper ends with some views on the way ahead regarding the linking of risk decisions to target setting at the workplace and views on how Case information may be retrieved and used on a daily basis.« less

Empirical optimization of DFT  +  U and HSE for the band structure of ZnO

NASA Astrophysics Data System (ADS)

Bashyal, Keshab; Pyles, Christopher K.; Afroosheh, Sajjad; Lamichhane, Aneer; Zayak, Alexey T.

2018-02-01

ZnO is a well-known wide band gap semiconductor with promising potential for applications in optoelectronics, transparent electronics, and spintronics. Computational simulations based on the density functional theory (DFT) play an important role in the research of ZnO, but the standard functionals, like Perdew-Burke-Erzenhof, result in largely underestimated values of the band gap and the binding energies of the Zn3d electrons. Methods like DFT  +  U and hybrid functionals are meant to remedy the weaknesses of plain DFT. However, both methods are not parameter-free. Direct comparison with experimental data is the best way to optimize the computational parameters. X-ray photoemission spectroscopy (XPS) is commonly considered as a benchmark for the computed electronic densities of states. In this work, both DFT  +  U and HSE methods were parametrized to fit almost exactly the binding energies of electrons in ZnO obtained by XPS. The optimized parameterizations of DFT  +  U and HSE lead to significantly worse results in reproducing the ion-clamped static dielectric tensor, compared to standard high-level calculations, including GW, which in turn yield a perfect match for the dielectric tensor. The failure of our XPS-based optimization reveals the fact that XPS does not report the ground state electronic structure for ZnO and should not be used for benchmarking ground state electronic structure calculations.

Screening of Possible Re-Substitutional Elements in Single-Crystal Ni-Based Superalloys: A Viewpoint From Interdiffusion Coefficients in Ni-Al-X Ternaries

NASA Astrophysics Data System (ADS)

Chen, Juan; Zhang, Lijun; Lu, Xiao-Gang

2018-07-01

A popular area of research in the field of high-temperature alloys concerns the search of substitutional elements for Re in order to manufacture single-crystal Ni-based superalloys with less or even no Re addition. To find the elements with similar or even lower diffusion coefficients than Re is an effective strategy. Based on 29 fcc diffusion couples in ternary Ni-Al-X (X = Re, Os, and Ir) systems, high-throughput measurement of composition- and temperature-dependent interdiffusivity matrices was performed using our recently developed numerical inverse method implemented in HitDIC software. The reliability of the determined interdiffusivities was validated by comprehensively comparing the model-predicted composition/interdiffusion flux profiles for each diffusion couple with the corresponding experimental data. Moreover, we also conducted a comparison with the interdiffusivities evaluated using the traditional Matano-Kirkaldy method as well as those from the literature and in boundary binary systems. After that, a comprehensive comparison of the interdiffusion coefficients in fcc Ni-2 wt pct Al-6 wt pct X (X = Ti, Co, Ni, Nb, Mo, Ru, Rh, Ta, W, Re, Os, Ir, and Pt) alloys at 1423 K to 1573 K was conducted. Results indicate that the diffusion rate of Re is lower than that of Os at 1473 K and 1523 K; but higher at 1573 K, while the diffusion rate of Ir is always slightly higher than those of Os and Re at 1473 K to 1573 K. Further analysis of the magnitude of the interdiffusion coefficient correlates with the alloying concentration, activation energy, atomic number, and atomic radius of different diffusing transition metal species ( i.e., Ti, Co, Ni, Nb, Mo, Ru, Rh, Ta, W, Re, Os, Ir, and Pt) was conducted, which is expected to provide useful information regarding element choice in the development of new-generation Ni-based single-crystal superalloys.

Screening of Possible Re-Substitutional Elements in Single-Crystal Ni-Based Superalloys: A Viewpoint From Interdiffusion Coefficients in Ni-Al-X Ternaries

NASA Astrophysics Data System (ADS)

Chen, Juan; Zhang, Lijun; Lu, Xiao-Gang

2018-05-01

A popular area of research in the field of high-temperature alloys concerns the search of substitutional elements for Re in order to manufacture single-crystal Ni-based superalloys with less or even no Re addition. To find the elements with similar or even lower diffusion coefficients than Re is an effective strategy. Based on 29 fcc diffusion couples in ternary Ni-Al-X (X = Re, Os, and Ir) systems, high-throughput measurement of composition- and temperature-dependent interdiffusivity matrices was performed using our recently developed numerical inverse method implemented in HitDIC software. The reliability of the determined interdiffusivities was validated by comprehensively comparing the model-predicted composition/interdiffusion flux profiles for each diffusion couple with the corresponding experimental data. Moreover, we also conducted a comparison with the interdiffusivities evaluated using the traditional Matano-Kirkaldy method as well as those from the literature and in boundary binary systems. After that, a comprehensive comparison of the interdiffusion coefficients in fcc Ni-2 wt pct Al-6 wt pct X (X = Ti, Co, Ni, Nb, Mo, Ru, Rh, Ta, W, Re, Os, Ir, and Pt) alloys at 1423 K to 1573 K was conducted. Results indicate that the diffusion rate of Re is lower than that of Os at 1473 K and 1523 K; but higher at 1573 K, while the diffusion rate of Ir is always slightly higher than those of Os and Re at 1473 K to 1573 K. Further analysis of the magnitude of the interdiffusion coefficient correlates with the alloying concentration, activation energy, atomic number, and atomic radius of different diffusing transition metal species (i.e., Ti, Co, Ni, Nb, Mo, Ru, Rh, Ta, W, Re, Os, Ir, and Pt) was conducted, which is expected to provide useful information regarding element choice in the development of new-generation Ni-based single-crystal superalloys.

Heat shock factor-1 knockout induces multidrug resistance gene, MDR1b, and enhances P-glycoprotein (ABCB1)-based drug extrusion in the heart

PubMed Central

Krishnamurthy, Karthikeyan; Vedam, Kaushik; Kanagasabai, Ragu; Druhan, Lawrence J.; Ilangovan, Govindasamy

2012-01-01

Heat-shock factor 1 (HSF-1), a transcription factor for heat-shock proteins (HSPs), is known to interfere with the transcriptional activity of many oncogenic factors. In the present work, we have discovered that HSF-1 ablation induced the multidrug resistance gene, MDR1b, in the heart and increased the expression of P-glycoprotein (P-gp, ABCB1), an ATP binding cassette that is usually associated with multidrug-resistant cancer cells. The increase in P-gp enhanced the extrusion of doxorubicin (Dox) to alleviate Dox-induced heart failure and reduce mortality in mice. Dox-induced left ventricular (LV) dysfunction was significantly reduced in HSF-1−/− mice. DNA-binding activity of NF-κB was higher in HSF-1−/− mice. IκB, the NF-κB inhibitor, was depleted due to enhanced IκB kinase (IKK)-α activity. In parallel, MDR1b gene expression and a large increase in P-gp and lowering Dox loading were observed in HSF-1−/− mouse hearts. Moreover, application of the P-gp antagonist, verapamil, increased Dox loading in HSF-1−/− cardiomyocytes, deteriorated cardiac function in HSF-1−/− mice, and decreased survival. MDR1 promoter activity was higher in HSF-1−/− cardiomyocytes, whereas a mutant MDR1 promoter with heat-shock element (HSE) mutation showed increased activity only in HSF-1+/+ cardiomyocytes. However, deletion of HSE and NF-κB binding sites diminished luminescence in both HSF-1+/+ and HSF-1−/− cardiomyocytes, suggesting that HSF-1 inhibits MDR1 activity in the heart. Thus, because high levels of HSF-1 are attributed to poor prognosis of cancer, systemic down-regulation of HSF-1 before chemotherapy is a potential therapeutic approach to ameliorate the chemotherapy-induced cardiotoxicity and enhance cancer prognosis. PMID:22615365

Late veneer and late accretion to the terrestrial planets

NASA Astrophysics Data System (ADS)

Brasser, R.; Mojzsis, S. J.; Werner, S. C.; Matsumura, S.; Ida, S.

2016-12-01

It is generally accepted that silicate-metal ('rocky') planet formation relies on coagulation from a mixture of sub-Mars sized planetary embryos and (smaller) planetesimals that dynamically emerge from the evolving circum-solar disc in the first few million years of our Solar System. Once the planets have, for the most part, assembled after a giant impact phase, they continue to be bombarded by a multitude of planetesimals left over from accretion. Here we place limits on the mass and evolution of these planetesimals based on constraints from the highly siderophile element (HSE) budget of the Moon. Outcomes from a combination of N-body and Monte Carlo simulations of planet formation lead us to four key conclusions about the nature of this early epoch. First, matching the terrestrial to lunar HSE ratio requires either that the late veneer on Earth consisted of a single lunar-size impactor striking the Earth before 4.45 Ga, or that it originated from the impact that created the Moon. An added complication is that analysis of lunar samples indicates the Moon does not preserve convincing evidence for a late veneer like Earth. Second, the expected chondritic veneer component on Mars is 0.06 weight percent. Third, the flux of terrestrial impactors must have been low (≲10-6 M⊕ Myr-1) to avoid wholesale melting of Earth's crust after 4.4 Ga, and to simultaneously match the number of observed lunar basins. This conclusion leads to an Hadean eon which is more clement than assumed previously. Last, after the terrestrial planets had fully formed, the mass in remnant planetesimals was ∼10-3 M⊕, lower by at least an order of magnitude than most previous models suggest. Our dynamically and geochemically self-consistent scenario requires that future N-body simulations of rocky planet formation either directly incorporate collisional grinding or rely on pebble accretion.

Towards understanding the mechanism of rhenium and osmium precipitation in tungsten and its implication for tungsten-based alloys

NASA Astrophysics Data System (ADS)

Li, Yu-Hao; Zhou, Hong-Bo; Deng, Huiqiu; Lu, Gang; Lu, Guang-Hong

2018-07-01

Using a first-principles method in combination with thermodynamic models, we investigate the interaction between rhenium/osmium (Re/Os) and defects to explore the mechanism of radiation-induced Re/Os precipitation in tungsten (W). We demonstrate that radiation-induced defects play a key role in the solute precipitation in W, especially for self-interstitial atoms (SIAs). The presence of SIAs can significantly reduce the total nucleation free energy change of Re/Os, and thus facilitate the nucleation of Re/Os in W. Further, SIA is shown to be easily trapped by Re/Os once overcoming a low energy barrier, forming a W-Re/Os mixed dumbbell. Such W-Re/Os dumbbell forms a high stable Re/Os-Re/Os dumbbell structure with the substitutional Re/Os atoms, which can serve as a trapping centre for subsequent interstitial-Re/Os, leading to the growth of Re/Os-rich clusters. Consequently, an interstitial-mediated migration and aggregation mechanism for Re/Os precipitation in W has been proposed. Our results reveale that the alloying elements-defects interaction has significantly effect on their behaviors under irradiation, which should be considered in the design of W-based alloys for future fusion devices.

Fractionation of the platinum-group elments and Re during crystallization of basalt in Kilauea Iki Lava Lake, Hawaii

USGS Publications Warehouse

Pitcher, L.; Helz, R.T.; Walker, R.J.; Piccoli, P.

2009-01-01

Kilauea Iki lava lake formed during the 1959 summit eruption of Kilauea Volcano, then crystallized and differentiated over a period of 35??years. It offers an opportunity to evaluate the fractionation behavior of trace elements in a uniquely well-documented basaltic system. A suite of 14 core samples recovered from 1967 to 1981 has been analyzed for 5 platinum-group elements (PGE: Ir, Os, Ru, Pt, Pd), plus Re. These samples have MgO ranging from 2.4 to 26.9??wt.%, with temperatures prior to quench ranging from 1140????C to ambient (110????C). Five eruption samples were also analyzed. Osmium and Ru concentrations vary by nearly four orders of magnitude (0.0006-1.40??ppb for Os and 0.0006-2.01??ppb for Ru) and are positively correlated with MgO content. These elements behaved compatibly during crystallization, mostly likely being concentrated in trace phases (alloy or sulfide) present in olivine phenocrysts or included chromite. Iridium also correlates positively with MgO, although less strongly than Os and Ru. The somewhat poorer correlation for Ir, compared with Os and Ru, may reflect variable loss of Ir as volatile IrF6 in some of the most magnesian samples. Rhenium is negatively correlated with MgO, behaving as an incompatible trace element. Its behavior in the lava lake is complicated by apparent volatile loss of Re, as suggested by a decrease in Re concentration with time of quenching for lake samples vs. eruption samples. Platinum and Pd concentrations are negatively, albeit weakly, correlated with MgO, so these elements were modestly incompatible during crystallization of the major silicate phases. Palladium contents peaked before precipitation of immiscible sulfide liquid, however, and decline sharply in the most differentiated samples. In contrast, Pt appears to have been unaffected by sulfide precipitation. Microprobe data confirm that Pd entered the sulfide liquid before Re, and that Pt is not strongly chalcophile in this system. Occasional high Pt values in both eruption and lava lake samples suggest the presence of unevenly distributed, unidentified Pt-rich trace phases in some Kilauea Iki materials. Estimated mineral (olivine + chromite)/melt D values for Os, Ir, Ru and Pt for equilibrium crystallization for samples from ~ 7 to 27??wt.% MgO are 26, 8.2, 19 and 0.55, respectively. These Os, Ir and Ru estimates are somewhat higher than previous estimates for similar systems. If fractional crystallization is instead assumed, D values are much more similar. Results confirm many prior observations in other mafic systems that olivine (together with included phases) has a major effect on absolute and relative abundances of Re and the PGE. The relatively linear correlations between these elements and MgO potentially permit accurate estimation of the concentrations of these elements in the primary melts of comparable systems, especially in instances where the MgO content of the primary melt is well constrained. ?? 2008 Elsevier B.V.

Partitioning of Re and Os between liquid metal and magnesiowüstite at high pressure

NASA Astrophysics Data System (ADS)

Fortenfant, S. S.; Rubie, D. C.; Reid, J.; Dalpé, C.; Capmas, F.; Gessmann, C. K.

2003-09-01

In order to study the partitioning of Re and Os between liquid iron-rich alloy and magnesiowüstite at high pressure, multi-anvil experiments have been performed on samples of Fe-Ni-Os-Re-O (4-8 wt.% Os and 4-12 wt.% Re) metal contained in MgO single crystal capsules. The range of pressure-temperature conditions was 5-10 GPa and 1900-2200 °C with experimental run durations of 6-30 min. During the experiments, the MgO reacted with the liquid metal to form magnesiowüstite. Compositions of the quenched liquid metal and the FeO, MgO and NiO contents of magnesiowüstite were determined by electron microprobe. Re and Os concentrations in magnesiowüstite were determined by LA-ICP-MS using a Re-Os-doped silicate glass standard. Based on the experimental results and assuming a valence of +2 for both Re and Os in magnesiowüstite, liquid metal-magnesiowüstite distribution coefficients ( KDmet/mw) are 60-240 for Re and 1.3×10 4 to 3.1×10 4 for Os. Within the uncertainties, there is no observable effect of either temperature or pressure on the partitioning of Re and Os over the range of experimental conditions. However, the values are very low compare to metal-silicate KDmet/mw values determined at 1 bar and 1400 °C (3×10 9 for Re and 7×10 6 for Os [Geochim. Cosmochim. Acta 65 (2001) 2161; Am. Mineral. 85 (2000) 912]). KDmet/mw values, assuming core-mantle equilibrium, are estimated to be ˜68 for both elements. Thus, although mantle concentrations of Re may be explained by core-mantle equilibration at high pressure and temperature, the experimentally determined distribution coefficients for Os are several orders of magnitude too high. Our results are therefore consistent with the "late veneer" hypothesis as an explanation for the mantle concentrations of highly siderophile elements. However, a consequence of the late veneer would be domains in the deep mantle with suprachondritic Re/Os ratios.

A Re-Os Study of Depleted Trench Peridotites from Northern Mariana

NASA Astrophysics Data System (ADS)

Ghosh, T.; Snow, J. E.; Heri, A. R.; Brandon, A. D.; Ishizuka, O.

2017-12-01

Trench peridotites provide information about the influence of subduction initiation on the extent of mantle wedge melting. They preserve melting records throughout subduction history, and as a result, likely experience multiple melt extraction events leading to successive depletion of melt/fluid mobile major and trace elements. To track melting histories of trench peridotites, Re-Os and PGEs can be used as reliable tracers to constrain early melt extraction or re-fertilization events. The Izu-Bonin-Mariana arc, being the largest intra-oceanic subduction system, provides an excellent area to study the formation of supra-subduction zone mantle and crust. Residual peridotite (harzburgite and dunite) samples were collected by dredging from the landward slope of the northern Mariana Trench. The samples are serpentinized to various extents (typical of abyssal peridotites), leaving behind relict grains of spinel, enstatite and olivine embedded within a serpentine matrix along with occasional interstitial diopside. Major element analyses of primary minerals reveal a wide range of variations in Cr# of spinels from 0.31-0.85 indicating 16-20% of melt fraction with dunites apparently experiencing the highest amount of partial melting. For Re-Os and PGE geochemistry, samples with high amounts of spinel (>4 vol %) and variable Cr# were chosen. Initial results show that bulk rock 187Os/188Os ratios range from 0.1113 to 0.1272. All of the samples are sub-chondritic, but in some cases, they are more radiogenic than average abyssal peridotites. Os abundances vary from 1-9 ppb. Sub-chondritic values can be attributed to the samples having evolved from a Re-depleted mantle source indicating a previous melt-extraction event. The cpx-harzburgites, having lower Cr# ( 0.4) are more radiogenic than ultra depleted dunites (Cr# 0.8), which might indicate preferential removal of Os during an apparent higher degree of partial melting experienced by dunites. The higher 187Os/188Os ratios of cpx-harzburgites possibly imply a late stage melt-rock interaction event, which had refertilized the depleted samples in radiogenic Os. Since there are only trace amounts of sediments in the accretionary prism of N. Mariana, Os ratios of these trench peridotites are not influenced by Os from sediments.

K-shell absorption jump factors and jump ratios in elements between Tm ( Z = 69) and Os ( Z = 76) derived from new mass attenuation coefficient measurements

NASA Astrophysics Data System (ADS)

Kaya, Necati; Tıraşoğlu, Engin; Apaydın, Gökhan; Aylıkcı, Volkan; Cengiz, Erhan

2007-08-01

The K-shell absorption jump factors and jump ratios were derived from new mass attenuation coefficients measured using an energy dispersive X-ray fluorescence (EDXRF) spectrometer for Tm, Yb elements being Tm 2O 3, Yb 2O 3 compounds and pure Lu, Hf, Ta, W, Re and Os. The measurements, in the region 56-77 keV, were done in a transmission geometry utilizing the K α1 , K α2 , K β1 and K β2 X- rays from different secondary source targets (Yb, Ta, Os, W, Re and Ir, etc.) excited by the 123.6 keV γ-photons from an 57Co annular source and detected by an Ultra-LEGe solid state detector with a resolution of 150 eV at 5.9 keV. Experimental results have been compared with theoretically calculated values. The measured values of Tm, Yb, Lu, Hf, Ta, W, Re and Os are reported here for the first time.

Os isotopes in SNC meteorites and their implications to the early evolution of Mars and Earth

NASA Technical Reports Server (NTRS)

Jagoutz, E.; Luck, J. M.; Othman, D. Ben; Wanke, H.

1993-01-01

A new development on the measurement of the Os isotopic composition by mass spectrometry using negative ions opened a new field of applications. The Re-Os systematic provides time information on the differentiation of the nobel metals. The nobel metals are strongly partitioned into metal and sulphide phases, but also the generation of silicate melts might fractionate the Re-Os system. Compared to the other isotopic systems which are mainly dating the fractionation of the alkalis and alkali-earth elements, the Re-Os system is expected to disclose entirely new information about the geochemistry. Especially the differentiation and early evolution of the planets such as the formation of the core will be elucidated with this method.

II-I2-IV-VI4 (II = Sr,Ba; I = Cu,Ag; IV = Ge,Sn; VI = S,Se): Earth-Abundant Chalcogenides for Thin Film Photovoltaics

NASA Astrophysics Data System (ADS)

Zhu, Tong; Huhn, William P.; Shin, Donghyeop; Mitzi, David B.; Blum, Volker; Saparov, Bayrammurad

Chalcogenides such as CdTe, CIGSSe, and CZTSSe are successful for thin film photovoltaics (PV) but contain elements that are rare, toxic, or prone to the formation of detrimental antisite disorder. Recently, the BaCu2SnS4-xSex system has been shown to offer a prospective path to circumvent these problems. While early prototypes show efficiencies of a few percent, many avenues remain to optimize the materials, including the underlying chemical composition. In this work, we explore 16 compounds II-I2-IV-VI4 to help identify new candidate materials for PV, with predictions based on both known experimental and computationally derived structures that belong to five different space groups. We employ hybrid density functional theory (HSE06) to explore the band gap tunability by substituting different elements, and other characteristics such as the effective mass and the absorption coefficient. Compounds containing Cu (rather than Ag) are found to have direct or nearly direct band gaps. Depending on the compound, replacing S with Se leads to a decrease of the predicted band gaps by 0.2-0.8 eV and to somewhat decreasing hole effective masses.

Composition of the lithospheric mantle in the northern part of Siberian craton: Constraints from peridotites in the Obnazhennaya kimberlite

NASA Astrophysics Data System (ADS)

Sun, Jing; Liu, Chuan-Zhou; Kostrovisky, Sergey I.; Wu, Fu-Yuan; Yang, Jin-Hui; Chu, Zhu-Yin; Yang, Yue-Heng; Kalashnikova, Tatiana; Fan, Sheng

2017-12-01

The character of the lithospheric mantle of the northern Siberian craton is not well established; nearly all published data are for mantle xenoliths from a single kimberlite in the center of the craton (Udachnaya). We report major elements of the whole rock, trace elements data of clinopyroxene and Re-Os isotope and PGE concentration of mantle xenoliths from the Obnazhennaya kimberlite pipe (160 Ma) in the northern part of Siberian craton. The Obnazhennaya mantle xenoliths include spinel harzburgites, spinel dunites, spinel lherzolites and spinel-garnet lherzolite. The spinel harzburgites and dunites have refractory compositions, with 0.23-1.35 wt% Al2O3, 0.41-3.11 wt% CaO and 0.00-0.09 wt% TiO2, whereas the lherzolites (both spinel- and spinel-garnet-) have more fertile compositions, containing 2.16-6.55 wt% Al2O3, 2.91-7.55 wt% CaO and 0.04-0.15 wt% TiO2. The trace element compositions and mineralogical textures of the Obnazhennaya xenoliths indicate the occurrence of metasomatic enrichments, including carbonatite melts, basaltic melts from Siberian Trap and kimberlitic melts. The spinel harzburgites and dunites have 187Os/188Os of 0.11227-0.11637, giving a TRD age of 1.6-2.2 Ga. This suggests that old cratonic mantle still existed beneath the Obnazhennaya. In contrast, both spinel and spinel-garnet lherzolites have more radiogenic 187Os/188Os ratios (0.11931-0.17627), enriched P-PGEs. But the higher Al2O3 and Os character of these lherzolites suggest that they were not juvenile mantle but the refertilized ancient mantle. Therefore, our results suggest that the cratonic mantle beneath the northern part of Siberian craton contain both ancient and reworked lithospheric mantle, and the metasomatism may not be effective at overprinting/eroding the pre-existing lithosphere.

OsN2: Crystal structure and electronic properties

NASA Astrophysics Data System (ADS)

Montoya, Javier A.; Hernandez, Alexander D.; Sanloup, Chrystèle; Gregoryanz, Eugene; Scandolo, Sandro

2007-01-01

Osmium nitride belongs to a family of nitrides synthesized recently at high pressures from their parent elements. Here we show, based on first-principles calculations, that the crystal structure of osmium nitride is isostructural to marcasite. Excellent agreement is obtained between the authors' results and x-ray, Raman, and compressibility measurements. In the OsN2 marcasite structure single-bonded N2 units occupy the interstitial sites of the Os close-packed lattice, giving rise to a metallic compound. A comparison between the formation energies of OsN2 and PtN2 explains the similar thermodynamic conditions of formation reported experimentally for the two compounds.

Defensive pessimism, self-esteem and achievement goals: A person-centered approach.

PubMed

Ferradás Canedo, María M; Freire Rodríguez, Carlos; Regueiro Fernández, Bibiana; Valle Arias, Antonio

2018-02-01

The relationship between defensive pessimism, self-esteem, and achievement goals is a controversial issue. The main contribution of this research is the adoption of a person-centered approach to explore the existence of differentiated profiles of university students, which combine self-esteem and defensive pessimism. In addition, we analyze whether these profiles differ in their achievement goals (learning, performance-approach, performance-avoidance, and work-avoidance). 1,028 university students took part in the study. Four student profiles were identified: (a) HSE/MDP (high self-esteem and moderate defensive pessimism); (b) LSE/LDP (low self-esteem and low defensive pessimism); (c) HSE/LDP (high self-esteem and low defensive pessimism); and (d) LSE/HDP (low self-esteem and high defensive pessimism). These four profiles differ significantly in their achievement goals. The use of defensive pessimism may involve students with either low or high self-esteem, although the two profiles follow differentiated motivational achievement trajectories.

'Worst case' methodology for the initial assessment of societal risk from proposed major accident installations.

PubMed

Carter, D A; Hirst, I L

2000-01-07

This paper considers the application of one of the weighted risk indicators used by the Major Hazards Assessment Unit (MHAU) of the Health and Safety Executive (HSE) in formulating advice to local planning authorities on the siting of new major accident hazard installations. In such cases the primary consideration is to ensure that the proposed installation would not be incompatible with existing developments in the vicinity, as identified by the categorisation of the existing developments and the estimation of individual risk values at those developments. In addition a simple methodology, described here, based on MHAU's "Risk Integral" and a single "worst case" even analysis, is used to enable the societal risk aspects of the hazardous installation to be considered at an early stage of the proposal, and to determine the degree of analysis that will be necessary to enable HSE to give appropriate advice.

Identifying the distinct features of geometric structures for hole trapping to generate radicals on rutile TiO₂(110) in photooxidation using density functional theory calculations with hybrid functional.

PubMed

Wang, Dong; Wang, Haifeng; Hu, P

2015-01-21

Using density functional theory calculations with HSE 06 functional, we obtained the structures of spin-polarized radicals on rutile TiO2(110), which is crucial to understand the photooxidation at the atomic level, and further calculate the thermodynamic stabilities of these radicals. By analyzing the results, we identify the structural features for hole trapping in the system, and reveal the mutual effects among the geometric structures, the energy levels of trapped hole states and their hole trapping capacities. Furthermore, the results from HSE 06 functional are compared to those from DFT + U and the stability trend of radicals against the number of slabs is tested. The effect of trapped holes on two important steps of the oxygen evolution reaction, i.e. water dissociation and the oxygen removal, is investigated and discussed.

Health, Safety, and Environment Division annual report 1989

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wade, C.

1992-01-01

The primary responsibility of the Health, Safety, and Environment (HSE) Division at the Los Alamos National Laboratory is to provide comprehensive occupational health and safety programs, waste processing, and environmental protection. These activities are designed to protect the worker, the public, and the environment. Meeting the responsibilities involves many disciplines, including radiation protection, industrial hygiene, safety, occupational medicine, environmental science and engineering, analytical chemistry, epidemiology, and waste management. New and challenging health, safety, and environmental problems occasionally arise from the diverse research and development work of the Laboratory, and research programs in the HSE Division often stem from these appliedmore » needs. These programs continue but are also extended, as needed, to study specific problems for the Department of Energy. The result of these programs is to help develop better practices in occupational health and safety, radiation protection, and environmental sciences.« less

Sustaining global progress in E and P health, safety, and environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arscott, R.L.; Edwardes, R.J.; Ognedal, M.

1996-12-01

The third International Conference on Health, Safety and Environment (HSE) was held in New Orleans in June 1996. During this meeting, the technical committee members were asked to complete a questionnaire with two questions: (1) What are the three biggest improvements in the industry`s performance in the HSE function over the past 5 years? and (2) What are the three biggest challenges for the next 5 years? The results from 30 replies from industry experts were compared with a similar survey conducted at the 1991 meeting, where the question was, What are the key action items the industry should takemore » to enhance performance over the next decade? This article gives the most frequently occurring comments cited by the 1996 technical committee relating to the 1991 recommendations. This may be considered a mid-decade review of worldwide E and P progress.« less

Real-structure effects: Band gaps of Mg_xZn_{1-x}O, Cd_xZn_{1-x}O, and n-type ZnO from ab-initio calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schleife, A; Bechstedt, F

2012-02-15

Many-body perturbation theory is applied to compute the quasiparticle electronic structures and the optical-absorption spectra (including excitonic effects) for several transparent conducting oxides. We discuss HSE+G{sub 0}W{sub 0} results for band structures, fundamental band gaps, and effective electron masses of MgO, ZnO, CdO, SnO{sub 2}, SnO, In{sub 2}O{sub 3}, and SiO{sub 2}. The Bethe-Salpeter equation is solved to account for excitonic effects in the calculation of the frequency-dependent absorption coefficients. We show that the HSE+G{sub 0}W{sub 0} approach and the solution of the Bethe-Salpeter equation are very well-suited to describe the electronic structure and the optical properties of various transparentmore » conducting oxides in good agreement with experiment.« less

Screening and ranking framework (SRF) for geologic CO2 storagesite selection on the basis of HSE risk

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oldenburg, Curtis M.

2006-11-27

A screening and ranking framework (SRF) has been developedto evaluate potential geologic carbon dioxide (CO2) storage sites on thebasis of health, safety, and environmental (HSE) risk arising from CO2leakage. The approach is based on the assumption that CO2 leakage risk isdependent on three basic characteristics of a geologic CO2 storage site:(1) the potential for primary containment by the target formation; (2)the potential for secondary containment if the primary formation leaks;and (3) the potential for attenuation and dispersion of leaking CO2 ifthe primary formation leaks and secondary containment fails. Theframework is implemented in a spreadsheet in which users enter numericalscores representingmore » expert opinions or published information along withestimates of uncertainty. Applications to three sites in Californiademonstrate the approach. Refinements and extensions are possible throughthe use of more detailed data or model results in place of propertyproxies.« less

Os, Nd and Sr isotope and trace element geochemistry of the Muli picrites: Insights into the mantle source of the Emeishan Large Igneous Province

NASA Astrophysics Data System (ADS)

Li, Jie; Xu, Ji-Feng; Suzuki, Katsuhiko; He, Bin; Xu, Yi-Gang; Ren, Zhong-Yuan

2010-09-01

A suite of picrites and basalts from the Muli area, in the northwestern part of the Emeishan continental flood basalt province, provides new and valuable information on the geochemistry of the Emeishan Large Igneous Province (LIP) and its source. The Muli picrites can be classified as type-1 or type-2. The former shows ocean-island basalt-like trace element characteristics, with γ Os (260 Ma) values and ɛ Nd (260 Ma) values ranging from + 7.5 to + 11.5 and from + 6.0 to + 7.8, respectively. This is the first time that picrites with highly radiogenic Os and high Os contents (up to 3.3 ppb) have been recognized in the Emeishan LIP. These characteristics probably reflect a relatively enriched component in the Emeishan LIP source. The type-2 picrites are characterized by non-radiogenic γ Os (260 Ma) values ranging from - 4.2 to - 0.3, and they may be further subdivided into type-2A and type-2B picrites. Type-2A picrites contain moderate amounts of the light rare earth elements (LREEs), have low Ce N/Yb N values (1.1-2.0), and a relatively high initial ɛ Nd (+ 5.0 to + 6.6). In terms of Os and Nd isotopes, the Muli type-2A picrites are similar to the Song Da komatiites of Vietnam and the Gorgona Island picrites, revealing the existence of a depleted mantle component in the Emeishan LIP source. In contrast with the type-2A picrites, type-2B lavas exhibit a negative Nb anomaly and relatively lower initial ɛ Nd and γ Os values (Nb/La > 1.8; ɛ Nd (260 Ma) = - 5.5 to + 6.4; γ Os (260 Ma) = - 4.2 to - 1.9), suggesting that the type-2B lavas have a depleted mantle source, similar to type-2A, but that the type-2B lavas are also influenced by various degrees of mixing of depleted plume-derived melt, sub-continental lithospheric mantle, and/or continental crust. Given that the basalts in the Muli area show similar geochemical features to those of the type-2B picrites, their origins are inferred to be similar.

Constraints on The Coupled Thermal Evolution of the Earth's Core and Mantle, The Age of The Inner Core, And The Origin of the 186Os/188Os Core(?) Signal in Plume-Derived Lavas

NASA Astrophysics Data System (ADS)

Lassiter, J. C.

2005-12-01

Thermal and chemical interaction between the core and mantle has played a critical role in the thermal and chemical evolution of the Earth's interior. Outer core convection is driven by core cooling and inner core crystallization. Core/mantle heat transfer also buffers mantle potential temperature, resulting in slower rates of mantle cooling (~50-100 K/Ga) than would be predicted from the discrepancy between current rates of surface heat loss (~44 TW) and internal radioactive heat production (~20 TW). Core/mantle heat transfer may also generate thermal mantle plumes responsible for ocean island volcanic chains such as the Hawaiian Islands. Several studies suggest that mantle plumes, in addition to transporting heat from the core/mantle boundary, also carry a chemical signature of core/mantle interaction. Elevated 186Os/188Os ratios in lavas from Hawaii, Gorgona, and in the 2.8 Ga Kostomuksha komatiites have been interpreted as reflecting incorporation of an outer core component with high time-integrated Pt/Os and Re/Os ( Brandon et al., 1999, 2003; Puchtel et al., 2005). Preferential partitioning of Os relative to Re and Pt into the inner core during inner core growth may generate elevated Re/Os and Pt/Os ratios in the residual outer core. Because of the long half-life of 190Pt (the parent of 186Os, t1/2 = 489 Ga), an elevated 186Os/188Os outer core signature in plume lavas requires that inner core crystallization began early in Earth history, most likely prior to 3.5 Ga. This in turn requires low time-averaged core/mantle heat flow (<~2.5 TW) or large quantities of heat-producing elements in the core. Core/mantle heat flow may be estimated using boundary-layer theory, by measuring the heat transported in mantle plumes, by estimating the heat transported along the outer core adiabat, or by comparing the rates of heat production, surface heat loss, and secular cooling of the mantle. All of these independent methods suggest time-averaged core/mantle heat flow of ~5-14 TW. In the absence of heat-producing elements in the core, such high heat flow rates require an inner core younger than ~1 Ga and preclude the development of significant 186Os enrichment in the outer core. Experimental studies suggest that potassium may partition into Fe-S-O liquids during core formation. Radioactive decay of potassium in the core could provide an additional heat source and reconcile geophysical evidence for high core/mantle heat flow with apparent geochemical evidence for an ancient inner core. However, high concentrations of chalcophile elements such as Cu in the mantle are inconsistent with significant segregation of a S-rich liquid during core formation, precluding K partitioning into the core by this mechanism. Furthermore, core formation scenarios that would lead to high K content in the core (e.g., core formation prior to terrestrial volatile depletion) also result in high core Pb concentrations. Core/mantle interaction would then produce strong negative correlations between 186Os/188Os and 207Pb/204Pb ratios, but such correlations are not observed. In summary, elevated 186Os/188Os ratios in some plume-derived lavas are unlikely to reflect core/mantle interaction because the inner core is too young for this isotopic signature to have developed in the outer core. Melt generation from pyroxenite or fractionation of PGEs between sulfide melts and monosulfide solid solutions provide alternative mechanisms for generating ancient mantle reservoirs with elevated Pt/Os and 186Os/188Os.

The Os-AKT1 Channel Is Critical for K+ Uptake in Rice Roots and Is Modulated by the Rice CBL1-CIPK23 Complex[W][OPEN

PubMed Central

Li, Juan; Long, Yu; Qi, Guo-Ning; Li, Juan; Xu, Zi-Jian; Wu, Wei-Hua; Wang, Yi

2014-01-01

Potassium (K+) is one of the essential nutrient elements for plant growth and development. Plants absorb K+ ions from the environment via root cell K+ channels and/or transporters. In this study, the Shaker K+ channel Os-AKT1 was characterized for its function in K+ uptake in rice (Oryza sativa) roots, and its regulation by Os-CBL1 (Calcineurin B-Like protein1) and Os-CIPK23 (CBL-Interacting Protein Kinase23) was investigated. As an inward K+ channel, Os-AKT1 could carry out K+ uptake and rescue the low-K+-sensitive phenotype of Arabidopsis thaliana akt1 mutant plants. Rice Os-akt1 mutant plants showed decreased K+ uptake and displayed an obvious low-K+-sensitive phenotype. Disruption of Os-AKT1 significantly reduced the K+ content, which resulted in inhibition of plant growth and development. Similar to the AKT1 regulation in Arabidopsis, Os-CBL1 and Os-CIPK23 were identified as the upstream regulators of Os-AKT1 in rice. The Os-CBL1-Os-CIPK23 complex could enhance Os-AKT1-mediated K+ uptake. A phenotype test confirmed that Os-CIPK23 RNAi lines exhibited similar K+-deficient symptoms as the Os-akt1 mutant under low K+ conditions. These findings demonstrate that Os-AKT1-mediated K+ uptake in rice roots is modulated by the Os-CBL1-Os-CIPK23 complex. PMID:25096783

Genetic analysis of the heparan modification network in Caenorhabditis elegans.

PubMed

Townley, Robert A; Bülow, Hannes E

2011-05-13

Heparan sulfates (HS) are highly modified sugar polymers in multicellular organisms that function in cell adhesion and cellular responses to protein signaling. Functionally distinct, cell type-dependent HS modification patterns arise as the result of a conserved network of enzymes that catalyze deacetylations, sulfations, and epimerizations in specific positions of the sugar residues. To understand the genetic interactions of the enzymes during the HS modification process, we have measured the composition of HS purified from mutant strains of Caenorhabditis elegans. From these measurements we have developed a genetic network model of HS modification. We find the interactions to be highly recursive positive feed-forward and negative feedback loops. Our genetic analyses show that the HS C-5 epimerase hse-5, the HS 2-O-sulfotransferase hst-2, or the HS 6-O-sulfotransferase hst-6 inhibit N-sulfation. In contrast, hse-5 stimulates both 2-O- and 6-O-sulfation and, hst-2 and hst-6 inhibit 6-O- and 2-O-sulfation, respectively. The effects of hst-2 and hst-6 on N-sulfation, 6-O-sulfation, and 2-O-sulfation appear largely dependent on hse-5 function. This core of regulatory interactions is further modulated by 6-O-endosulfatase activity (sul-1). 47% of all 6-O-sulfates get removed from HS and this editing process is dependent on hst-2, thereby providing additional negative feedback between 2-O- and 6-O-sulfation. These findings suggest that the modification patterns are highly sensitive to the relative composition of the HS modification enzymes. Our comprehensive genetic analysis forms the basis of understanding the HS modification network in metazoans.

The local lymph node assay in practice: a current regulatory perspective.

PubMed

Cockshott, A; Evans, P; Ryan, C A; Gerberick, G F; Betts, C J; Dearman, R J; Kimber, I; Basketter, D A

2006-07-01

Following the formal acceptance of the local lymph node assay (LLNA) as an Organization for Economic Cooperation and Development (OECD) guideline in April 2002, the UK Health and Safety Executive (HSE) informed notifiers that this was now the method of choice for the assessment of skin sensitization potential under the EU notification scheme for new industrial chemicals (NONS). This paper summarizes the experience of the HSE for the 2-year period immediately following the issuing of this statement, during which 48 LLNA study reports were assessed for notification purposes. The issues discussed here include adherence to the OECD guideline, interpretation of results, and classification outcomes. Generally, notifying laboratories followed the OECD guideline successfully, with regard to the sex/ strain/numbers of mice used, the precise process used for measurement of cell proliferation, and the use of recommended vehicles and positive controls. Initially, use of the individual animal approach (measuring the cell proliferation in each animal rather than for a pooled dose group) highlighted problems caused by technical inexperience, but these were overcome by practice. Toxicity or irritation were found to be minor factors in dose selection; more important was the choice of vehicle to correctly maximize the test substance concentration, while maintaining appropriate application properties. Contrary to concerns that the LLNA would prove to be less sensitive or more sensitive than the traditionally used Guinea Pig Maximization Test (GPMT), the proportion of new substances classified as skin sensitizers was within the range observed in previous years. Although the sample size is relatively small, the experience of the HSE indicates that the LLNA is satisfactory for routine regulatory use.

Controlling exposure to chemicals: a simple guide.

PubMed

Hay, Alastair

2006-09-01

Controlling exposure to chemicals in the workplace has been made easier by the use of a guide published by the U.K. Health and Safety Executive (HSE). Known as COSHH (Control of Substances Hazardous to Health Regulations) Essentials, the guide is a simple five-step procedure to devise appropriate control strategies to reduce exposures to various substances under different conditions. U.K. health and safety law requires risk assessments prior to use of hazardous substances and installation of appropriate control strategies before work commences. A 1996 survey of 1500 safety managers and trade union safety representatives revealed that the majority had little understanding of occupational safety limits for chemicals. Small- and medium-sized companies had little understanding of limits, and most could not develop control strategies. A new approach was required. COSHH Essentials is it. Developed over 3 years by a working group of hygienists and toxicologists representing HSE, industry, trade unions, and independent experts, the guide is now available in both paper-based and internet versions. It applies a hazard banding approach validated by data for 111 substances that have well-founded U.K. occupational exposure limits. New users select an appropriate hazard band for chemicals based on risk phrases. Details about dustiness for powders or volatility for liquids are inserted, and the guide allocates substances to one of four exposure bands linked, in turn, to specific control strategies. Now accessible through the HSE web site, COSHH Essentials will offer control strategies for both single chemicals and whole processes. To date over 300,000 risk assessments have been carried out using the internet version of COSHH Essentials.

Development of new demi-span equations from a nationally representative sample of older people to estimate adult height.

PubMed

Hirani, Vasant; Aresu, Maria

2012-03-01

To develop new equations for the calculation of body mass index (BMI) of adults aged 65 and older for when an actual height measurement may not be possible or reflect attained height because of loss of height with aging or conditions such as kyphosis or osteoporosis. Cross-sectional, nationally representative samples; data from 1994, 2000 2005, and 2007. Adults aged 65 and older living in England. Two thousand four hundred fifty-four noninstitutitionalized adults aged 65 and older taking part in the Health Survey for England (HSE). Height and demi-span measurements (defined as the distance between the mid-point of the sternal notch and the finger roots with the arm outstretched laterally) were taken according to standard procedures. Sex- and age-specific regression equations were produced from measured height and demi-span (DEH) using HSE 2005 data to develop new DEH equations (DEH(age)) from people aged 65 and older. The derived DEH(age) equation was applied to the HSE data for 1994, 2000, and 2007 to attempt to test its reliability. Analysis showed that DEH(age) predicts current height better than when using the Bassey equation (DEH(B) (assey)). DEH(age) can be used instead of a height measurement to derive other anthropometric indices such as body mass index (BMI) in older people. The new equations developed for predicting current height in older people can be used to calculate BMI more accurately in older people. © 2012, Copyright the Authors Journal compilation © 2012, The American Geriatrics Society.

IFNγ inhibits G-CSF induced neutrophil expansion and invasion of the CNS to prevent viral encephalitis.

PubMed

Ramakrishna, Chandran; Cantin, Edouard M

2018-01-01

Emergency hematopoiesis facilitates the rapid expansion of inflammatory immune cells in response to infections by pathogens, a process that must be carefully regulated to prevent potentially life threatening inflammatory responses. Here, we describe a novel regulatory role for the cytokine IFNγ that is critical for preventing fatal encephalitis after viral infection. HSV1 encephalitis (HSE) is triggered by the invasion of the brainstem by inflammatory monocytes and neutrophils. In mice lacking IFNγ (GKO), we observed unrestrained increases in G-CSF levels but not in GM-CSF or IL-17. This resulted in uncontrolled expansion and infiltration of apoptosis-resistant, degranulating neutrophils into the brainstem, causing fatal HSE in GKO but not WT mice. Excessive G-CSF in GKO mice also induced granulocyte derived suppressor cells, which inhibited T-cell proliferation and function, including production of the anti-inflammatory cytokine IL-10. Unexpectedly, we found that IFNγ suppressed G-CSF signaling by increasing SOCS3 expression in neutrophils, resulting in apoptosis. Depletion of G-CSF, but not GM-CSF, in GKO mice induced neutrophil apoptosis and reinstated IL-10 secretion by T cells, which restored their ability to limit innate inflammatory responses resulting in protection from HSE. Our studies reveals a novel, complex interplay among IFNγ, G-CSF and IL-10, which highlights the opposing roles of G-CSF and IFNγ in regulation of innate inflammatory responses in a murine viral encephalitis model and reveals G-CSF as a potential therapeutic target. Thus, the antagonistic G-CSF-IFNγ interactions emerge as a key regulatory node in control of CNS inflammatory responses to virus infection.

Comparison of the Physical Activity and Sedentary Behaviour Assessment Questionnaire and the Short-Form International Physical Activity Questionnaire: An Analysis of Health Survey for England Data

PubMed Central

Scholes, Shaun; Bridges, Sally; Ng Fat, Linda; Mindell, Jennifer S.

2016-01-01

Background The Physical Activity and Sedentary Behaviour Assessment Questionnaire (PASBAQ), used within the Health Survey for England (HSE) at 5-yearly intervals, is not included annually due to funding and interview-length constraints. Policy-makers and data-users are keen to consider shorter instruments such as the Short-form International Physical Activity Questionnaire (IPAQ) for the annual survey. Both questionnaires were administered in HSE 2012, enabling comparative assessment in a random sample of 1252 adults. Methods Relative agreement using prevalence-adjusted bias-adjusted Kappa (PABAK) statistics was estimated for: sufficient aerobic activity (moderate-to-vigorous physical activity [MVPA] ≥150minutes/week); inactivity (MVPA<30minutes/week); and excessive sitting (≥540minutes/weekday). Cross-sectional associations with health outcomes were compared across tertiles of MVPA and tertiles of sitting time using logistic regression with tests for linear trend. Results Compared with PASBAQ data, IPAQ-assessed estimates of sufficient aerobic activity and inactivity were higher and lower, respectively; estimates of excessive sitting were higher. Demographic patterns in prevalence were similar. Agreement using PABAK statistics was fair-to-moderate for sufficient aerobic activity (0.32–0.49), moderate-to-substantial for inactivity (0.42–0.74), and moderate-to-substantial for excessive sitting (0.49–0.75). As with the PASBAQ, IPAQ-assessed MVPA and sitting each showed graded associations with mental well-being (women: P for trend = 0.003 and 0.004, respectively) and obesity (women: P for trend = 0.007 and 0.014, respectively). Conclusions Capturing habitual physical activity and sedentary behaviour through brief questionnaires is complex. Differences in prevalence estimates can reflect differences in questionnaire structure and content rather than differences in reported behaviour. Treating all IPAQ-assessed walking as moderate-intensity contributed to the differences in prevalence estimates. PASBAQ data will be used for population surveillance every 4 to 5 years. The current version of the Short-form IPAQ was included in HSE 2013–14 to enable more frequent assessment of physical activity and sedentary behaviour; a modified version with different item-ordering and additional questions on walking-pace and effort was included in HSE 2015. PMID:26990093

Erosion of the healthy soldier effect in veterans of US military service in Iraq and Afghanistan.

PubMed

Bollinger, Mary J; Schmidt, Susanne; Pugh, Jacqueline A; Parsons, Helen M; Copeland, Laurel A; Pugh, Mary Jo

2015-01-01

This research explores the healthy soldier effect (HSE) - a lower mortality risk among veterans relative to the general population-in United States (US) veterans deployed in support of operations in Iraq and Afghanistan (OEF/OIF/OND). While a HSE has been affirmed in other OEF/OIF/OND populations, US veterans of OEF/OIF/OND have not been systematically studied. Using US Department of Veterans Affairs (VA) administrative data, we identified veterans who (1) had been deployed in support of OEF/OIF/OND between 2002 and 2011 and (2) were enrolled in the VA health care system. We divided the VA population into VA health care utilizers and non-utilizers. We obtained Department of Defense (DOD) administrative data on the OEF/OIF/OND population and obtained VA and DOD mortality data excluding combat deaths from the analyses. Indirect standardization was used to compare VA and DOD cohorts to the US population using total population at risk to compute the Standardized Mortality Ratio (SMR). A directly standardized relative risk (DSRR) was calculated to enable comparisons between cohorts. To compare VA enrollee mortality on military specific characteristics, we used a DOD population standard. The overall VA SMR of 2.8 (95% Confidence Interval [CI] 2.8-2.9), VA utilizer SMR of 3.2 (95% CI 3.1-3.3), VA non-utilizer SMR of 0.9 (95% CI 0.8-1.1), and DOD SMR of 1.5 (95% CI 1.4-1.5) provide no evidence of a HSE in any cohort relative to the US standard population. Relative to DOD, both the total VA population SMR of 2.1 (95% CI 2.0-2.2) and the SMR for VA utilizers of 2.3 (95% CI 2.3-2.4) indicate mortality twice what would be expected given DOD mortality rates. In contrast, the VA enrollees who had not used clinical services had 40% lower than expected mortality relative to DOD. No support was found for the HSE among US veterans of OEF/OIF/OND. These findings may be attributable to a number of factors including post-deployment risk-taking behavior, an abbreviated follow up period, and the nature of the OEF/OIF/OND conflict.

Band structure and thermoelectric properties of half-Heusler semiconductors from many-body perturbation theory

NASA Astrophysics Data System (ADS)

Zahedifar, Maedeh; Kratzer, Peter

2018-01-01

Various ab initio approaches to the band structure of A NiSn and A CoSb half-Heusler compounds (A = Ti, Zr, Hf) are compared and their consequences for the prediction of thermoelectric properties are explored. Density functional theory with the generalized-gradient approximation (GGA), as well as the hybrid density functional HSE06 and ab initio many-body perturbation theory in the form of the G W0 approach, are employed. The G W0 calculations confirm the trend of a smaller band gap (0.75 to 1.05 eV) in A NiSn compared to the A CoSb compounds (1.13 to 1.44 eV) already expected from the GGA calculations. While in A NiSn materials the G W0 band gap is 20% to 50% larger than in HSE06, the fundamental gap of A CoSb materials is smaller in G W0 compared to HSE06. This is because G W0 , similar to PBE, locates the valence band maximum at the L point of the Brillouin zone, whereas it is at the Γ point in the HSE06 calculations. The differences are attributed to the observation that the relative positions of the d levels of the transition metal atoms vary among the different methods. Using the calculated band structures and scattering rates taking into account the band effective masses at the extrema, the Seebeck coefficients, thermoelectric power factors, and figures of merit Z T are predicted for all six half-Heusler compounds. Comparable performance is predicted for the n -type A NiSn materials, whereas clear differences are found for the p -type A CoSb materials. Using the most reliable G W0 electronic structure, ZrCoSb is predicted to be the most efficient material with a power factor of up to 0.07 W/(K2 m) at a temperature of 600 K. We find strong variations among the different ab initio methods not only in the prediction of the maximum power factor and Z T value of a given material, but also in comparing different materials to each other, in particular in the p -type thermoelectric materials. Thus we conclude that the most elaborate, but also most costly G W0 method is required to perform a reliable computational search for the optimum material.

Assessment of health risk related to the ingestion of trace metals through fish consumption in Todos os Santos Bay.

PubMed

de Santana, Carolina Oliveira; de Jesus, Taíse Bomfim; de Aguiar, Willian Moura; de Jesus Sant'anna Franca-Rocha, Washington; Soares, Carlos Alberto Caroso

2017-05-01

This study was carried out to evaluate the concentration of trace elements (As, Cd, Cu, Pb, and Zn) in the muscle of carnivorous fish species from three different areas of Todos os Santos Bay (BTS), Bahia State, Brazil. Trace elements were analyzed using inductively coupled plasma-optical emission spectrometry (ICP-OES), and consumption rates advisory for minimizing chronic systemic effects in children and adults were estimated. As concentrations in fish samples from Jiribatuba were higher than legal limits set by FAO, and Cd concentrations in fish from Iguape Bay were high in comparison with FAO and EC. This study provides information about the fish consumption limits, considering the elements concentrations observed in the analyses, in particular As and Cd, necessary for minimizing potential health risks.

Major, Trace, and Volatile (CO2, H2O, S, F, and Cl) Elements from 1000+ Hawaiian Olivine-hosted Melt Inclusions Reveal the Dynamics of Crustal Recycling

NASA Astrophysics Data System (ADS)

Marske, J. P.; Hauri, E. H.; Trusdell, F.; Garcia, M. O.; Pietruszka, A. J.

2015-12-01

Global cycling of volatile elements (H2O, CO2, F, S, Cl) via subduction to deep mantle followed by entrainment and melting within ascending mantle plumes is an enigmatic process that controls key aspects of hot spot volcanism (i.e. melting rate, magma supply, degassing, eruptive style). Variations in radiogenic isotope ratios (e.g.187Os/188Os) at hot spots such as Hawaii reveal magmatic processes within deep-seated mantle plumes (e.g. mantle heterogeneity, lithology, and melt transport). Shield-stage lavas from Hawaii likely originate from a mixed plume source containing peridotite and recycled oceanic crust (pyroxenite) based on variations of radiogenic isotopes. Hawaiian lavas display correlations among isotopes, major and trace elements [1] that might be expected to have an expression in the volatile elements. To investigate this link, we present Os isotopic ratios (n=51), and major, trace, and volatile elements from 1003 olivine-hosted melt inclusions (MI) and their host minerals from tephra from Koolau, Mauna Loa, Hualalai, Kilauea, and Loihi volcanoes. The data show a strong correlation between MI volatile contents and incompatible trace element ratios (La/Yb) with Os isotopes of the same host olivines and reveal large-scale volatile heterogeneity and zonation exists within the Hawaiian plume. 'Loa' chain lavas, which are thought to originate from greater proportions of recycled oceanic crust/pyroxenite, have MIs with lower H2O, S, F, and Cl contents compared to 'Kea' chain lavas that were derived from more peridotite-rich sources. The depletion of volatile elements in the 'Loa' volcano MIs can be explained if they tapped an ancient dehydrated oceanic crust component within the Hawaiian plume. Higher extents of melting beneath 'Loa' volcanoes can also explain these depletions. The presence of dehydrated recycled mafic material in the plume source suggests that subduction effectively devolatilizes part of the oceanic crust. These results are similar to the observed shifts in H2O/Ce ratios near the Easter and Samoan hotspots [2,3]. Thus, it appears that multiple hotspots may record relative H2O depletions and possibly other volatiles. [1] Hauri et al. 1996, Nature 382, 415-419. [2] Dixon et al. 2002, Nature 420:385-89 [3] Workman et al. 2006, EPSL 241:932-51.

Dicer-like 3 produces transposable element-associated 24-nt siRNAs that control agricultural traits in rice

PubMed Central

Wei, Liya; Gu, Lianfeng; Song, Xianwei; Cui, Xiekui; Lu, Zhike; Zhou, Ming; Wang, Lulu; Hu, Fengyi; Zhai, Jixian; Meyers, Blake C.; Cao, Xiaofeng

2014-01-01

Transposable elements (TEs) and repetitive sequences make up over 35% of the rice (Oryza sativa) genome. The host regulates the activity of different TEs by different epigenetic mechanisms, including DNA methylation, histone H3K9 methylation, and histone H3K4 demethylation. TEs can also affect the expression of host genes. For example, miniature inverted repeat TEs (MITEs), dispersed high copy-number DNA TEs, can influence the expression of nearby genes. In plants, 24-nt small interfering RNAs (siRNAs) are mainly derived from repeats and TEs. However, the extent to which TEs, particularly MITEs associated with 24-nt siRNAs, affect gene expression remains elusive. Here, we show that the rice Dicer-like 3 homolog OsDCL3a is primarily responsible for 24-nt siRNA processing. Impairing OsDCL3a expression by RNA interference caused phenotypes affecting important agricultural traits; these phenotypes include dwarfism, larger flag leaf angle, and fewer secondary branches. We used small RNA deep sequencing to identify 535,054 24-nt siRNA clusters. Of these clusters, ∼82% were OsDCL3a-dependent and showed significant enrichment of MITEs. Reduction of OsDCL3a function reduced the 24-nt siRNAs predominantly from MITEs and elevated expression of nearby genes. OsDCL3a directly targets genes involved in gibberellin and brassinosteroid homeostasis; OsDCL3a deficiency may affect these genes, thus causing the phenotypes of dwarfism and enlarged flag leaf angle. Our work identifies OsDCL3a-dependent 24-nt siRNAs derived from MITEs as broadly functioning regulators for fine-tuning gene expression, which may reflect a conserved epigenetic mechanism in higher plants with genomes rich in dispersed repeats or TEs. PMID:24554078

Heterogeneity of Systemic Oxidative Stress Profiles in COPD: A Potential Role of Gender.

PubMed

Maury, Jonathan; Gouzi, Farés; De Rigal, Philippe; Heraud, Nelly; Pincemail, Joël; Molinari, Nicolas; Pomiès, Pascal; Laoudj-Chenivesse, Dalila; Mercier, Jacques; Préfaut, Christian; Hayot, Maurice

2015-01-01

Oxidative stress (OS) plays a key role in the muscle impairment and exercise capacity of COPD patients. However, the literature reveals that systemic OS markers show great heterogeneity, which may hinder the prescription of effective antioxidant supplementation. This study therefore aimed to identify OS markers imbalance of COPD patients, relative to validated normal reference values, and to investigate the possibility of systemic OS profiles. We measured systemic enzymatic/nonenzymatic antioxidant and lipid peroxidation (LP) levels in 54 stable COPD patients referred for a rehabilitation program. The main systemic antioxidant deficits in these patients concerned vitamins and trace elements. Fully 89% of the COPD patients showed a systemic antioxidant imbalance which may have caused the elevated systemic LP levels in 69% of them. Interestingly, two patient profiles (clusters 3 and 4) had a more elevated increase in LP combined with increased copper and/or decreased vitamin C, GSH, and GPx. Further analysis revealed that the systemic LP level was higher in COPD women and associated with exercise capacity. Our present data therefore support future supplementations with antioxidant vitamins and trace elements to improve exercise capacity, but COPD patients will probably show different positive responses.

Platinum-group elements fractionation by selective complexing, the Os, Ir, Ru, Rh-arsenide-sulfide systems above 1020 °C

NASA Astrophysics Data System (ADS)

Helmy, Hassan M.; Bragagni, Alessandro

2017-11-01

The platinum-group element (PGE) contents in magmatic ores and rocks are normally in the low μg/g (even in the ng/g) level, yet they form discrete platinum-group mineral (PGM) phases. IPGE (Os, Ir, Ru) + Rh form alloys, sulfides, and sulfarsenides while Pt and Pd form arsenides, tellurides, bismuthoids and antimonides. We experimentally investigate the behavior of Os, Ru, Ir and Rh in As-bearing sulfide system between 1300 and 1020 °C and show that the prominent mineralogical difference between IPGE (+Rh) and Pt and Pd reflects different chemical preference in the sulfide melt. At temperatures above 1200 °C, Os shows a tendency to form alloys. Ruthenium forms a sulfide (laurite RuS2) while Ir and Rh form sulfarsenides (irarsite IrAsS and hollingworthite RhAsS, respectively). The chemical preference of PGE is selective: IPGE + Rh form metal-metal, metal-S and metal-AsS complexes while Pt and Pd form semimetal complexes. Selective complexing followed by mechanical separation of IPGE (and Rh)-ligand from Pt- and Pd-ligand associations lead to PGE fractionation.

Explorations on TiOsX (X=B, C, N, O and Si) alloys for potential superhard materials from first-principle calculation

NASA Astrophysics Data System (ADS)

Wu, Junyan; Zhang, Bo; Zhan, Yongzhong

2017-05-01

Using the first-principle calculations, we gained a deep insight of the structural, mechanical, electronic and thermal properties of the TiOs and TiOs-X (X=B, C, N, O and Si) compounds. The calculated results of formation enthalpy Hform and ternary transfer energy EXOs → Ti illustrate that O element exhibits strong Os site preference and all the compounds here are structurally stable. The results of mechanical properties confirm that there is no superhard character in those intermetallics which are mechanically stable. It is noted that the Ti7Os8Si possesses the best mechanical properties. All the compounds here show elastic anisotropy, and the Ti8Os7O exhibits the strongest elastic anisotropy, while the Ti8Os7Si strongly tends to be isotropic. There exists a mixture of covalent, ionic and metallic characters in these compounds. The covalent bond strength of Ti7Os8X is supposed to be better than that of the corresponding Ti8Os7X. Moreover, the minimum thermal conductivity kmin of these compounds are comparatively small and show dependence of directions, and they have potential thermal-insulating application in engineering.

Genetic Analysis of the Heparan Modification Network in Caenorhabditis elegans*

PubMed Central

Townley, Robert A.; Bülow, Hannes E.

2011-01-01

Heparan sulfates (HS) are highly modified sugar polymers in multicellular organisms that function in cell adhesion and cellular responses to protein signaling. Functionally distinct, cell type-dependent HS modification patterns arise as the result of a conserved network of enzymes that catalyze deacetylations, sulfations, and epimerizations in specific positions of the sugar residues. To understand the genetic interactions of the enzymes during the HS modification process, we have measured the composition of HS purified from mutant strains of Caenorhabditis elegans. From these measurements we have developed a genetic network model of HS modification. We find the interactions to be highly recursive positive feed-forward and negative feedback loops. Our genetic analyses show that the HS C-5 epimerase hse-5, the HS 2-O-sulfotransferase hst-2, or the HS 6-O-sulfotransferase hst-6 inhibit N-sulfation. In contrast, hse-5 stimulates both 2-O- and 6-O-sulfation and, hst-2 and hst-6 inhibit 6-O- and 2-O-sulfation, respectively. The effects of hst-2 and hst-6 on N-sulfation, 6-O-sulfation, and 2-O-sulfation appear largely dependent on hse-5 function. This core of regulatory interactions is further modulated by 6-O-endosulfatase activity (sul-1). 47% of all 6-O-sulfates get removed from HS and this editing process is dependent on hst-2, thereby providing additional negative feedback between 2-O- and 6-O-sulfation. These findings suggest that the modification patterns are highly sensitive to the relative composition of the HS modification enzymes. Our comprehensive genetic analysis forms the basis of understanding the HS modification network in metazoans. PMID:21454666

Impaired intrinsic immunity to HSV-1 in human iPSC-derived TLR3-deficient CNS cells

PubMed Central

Lafaille, Fabien G; Pessach, Itai M.; Zhang, Shen-Ying; Ciancanelli, Michael J.; Herman, Melina; Abhyankar, Avinash; Ying, Shui-Wang; Keros, Sotirios; Goldstein, Peter A.; Mostoslavsky, Gustavo; Ordovas-Montanes, Jose; Jouanguy, Emmanuelle; Plancoulaine, Sabine; Tu, Edmund; Elkabetz, Yechiel; Al-Muhsen, Saleh; Tardieu, Marc; Schlaeger, Thorsten M.; Daley, George Q.; Abel, Laurent; Casanova, Jean-Laurent; Studer, Lorenz; Notarangelo, Luigi D.

2012-01-01

In the course of primary infection with herpes simplex virus 1 (HSV-1), children with inborn errors of TLR3 immunity are prone to HSV-1 encephalitis (HSE) 1–3. We tested the hypothesis that the pathogenesis of HSE involves non hematopoietic central nervous system (CNS)-resident cells. We derived induced pluripotent stem cells (iPSCs) from the dermal fibroblasts of TLR3- and UNC-93B-deficient patients and from controls. These iPSCs were differentiated into highly purified populations of neural stem cells (NSCs), neurons, astrocytes and oligodendrocytes. The induction of IFN-β and/or IFN-γ1 in response to poly(I:C) stimulation was dependent on TLR3 and UNC-93B in all cells tested. However, the induction of IFN-β and IFN-γ1 in response to HSV-1 infection was impaired selectively in UNC-93B-deficient neurons and oligodendrocytes. These cells were also much more susceptible to HSV-1 infection than control cells, whereas UNC-93B-deficient NSCs and astrocytes were not. TLR3-deficient neurons were also found to be susceptible to HSV-1 infection. The rescue of UNC-93B- and TLR3-deficient cells with the corresponding wild-type allele demonstrated that the genetic defect was the cause of the poly(I:C) and HSV-1 phenotypes. The viral infection phenotype was further rescued by treatment with exogenous IFN-α/β, but not IFN-γ1.Thus, impaired TLR3- and UNC-93B-dependent IFN-α/β intrinsic immunity to HSV-1 in the CNS, in neurons and oligodendrocytes in particular, may underlie the pathogenesis of HSE in children with TLR3 pathway deficiencies. PMID:23103873

Tumor cytotoxicity by endothelial cells. Impairment of the mitochondrial system for glutathione uptake in mouse B16 melanoma cells that survive after in vitro interaction with the hepatic sinusoidal endothelium.

PubMed

Ortega, Angel L; Carretero, Julian; Obrador, Elena; Gambini, Juan; Asensi, Miguel; Rodilla, Vicente; Estrela, José M

2003-04-18

High GSH content associates with high metastatic activity in B16-F10 melanoma cells cultured to low density (LD B16M). GSH homeostasis was investigated in LD B16M cells that survive after adhesion to the hepatic sinusoidal endothelium (HSE). Invasive B16M (iB16M) cells were isolated using anti-Met-72 monoclonal antibodies and flow cytometry-coupled cell sorting. HSE-derived NO and H(2)O(2) caused GSH depletion and a decrease in gamma-glutamylcysteine synthetase activity in iB16M cells. Overexpression of gamma-glutamylcysteine synthetase heavy and light subunits led to a rapid recovery of cytosolic GSH, whereas mitochondrial GSH (mtGSH) further decreased during the first 18 h of culture. NO and H(2)O(2) damaged the mitochondrial system for GSH uptake (rates in iB16M were approximately 75% lower than in LD B16M cells). iB16M cells also showed a decreased activity of mitochondrial complexes II, III, and IV, less O(2) consumption, lower ATP levels, higher O(2) and H(2)O(2) production, and lower mitochondrial membrane potential. In vitro growing iB16M cells maintained high viability (>98%) and repaired HSE-induced mitochondrial damages within 48 h. However, iB16M cells with low mtGSH levels were highly susceptible to TNF-alpha-induced oxidative stress and death. Therefore depletion of mtGSH levels may represent a critical target to challenge survival of invasive cancer cells.

Processing Effects on the Antioxidant Activities of Beverage Blends Developed from Cyperus esculentus, Hibiscus sabdariffa, and Moringa oleifera Extracts.

PubMed

Badejo, Adebanjo A; Damilare, Akintoroye; Ojuade, Temitope D

2014-09-01

The discovery of bioactive compounds in foods has changed the dietary lifestyle of many people. Cyperus esculentus (tigernut) is highly underutilized in Africa, yet tigernut extract is highly profitable in Europe. This study aims to add value to tigernut extract by revealing its health benefits and food value. In this study, tigernut tubers were germinated or roasted and the extracts were combined with Moringa oleifera extract (MOE) or Hibiscus sabdariffa extract (HSE) and spiced with ginger to produce functional drinks. The drinks were evaluated for physicochemical characteristics, sensory parameters, and antioxidant potentials. The total phenolic content of each beverage was measured by the Folin-Ciocalteu method, and the antioxidant activity of each beverage was determined by the 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid assays. The beverages from the germinated tigernut extracts had the highest titratable acidity and the lowest pH, while beverages containing the roasted tigernut extract had the highest ∘Brix. Germination and roasting significantly enhanced the total phenolic content of the drinks. The beverage containing HSE and germinated tigernut extract had a total phenolic content of 45.67 mg/100 mL gallic acid equivalents, which was significantly higher than the total phenolic content of all other samples. The DPPH inhibition activity of the beverages prepared with germinated tigernut extracts was significantly higher than the DPPH inhibition activity of the beverages prepared with fresh tigernut extract. The taste and overall acceptability of drinks containing the roasted tigernut extract were preferred, while the color and appearance of drinks with the germinated samples were preferred. Roasting or germinating tigernuts before extraction and addition of MOE or HSE extracts is another way to add value and enhance the utilization of tigernuts.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, H., E-mail: li-huanglong@mail.tsinghua.edu.cn; Gillen, R.; Robertson, J., E-mail: jr214@cam.ac.uk

The screened exchange (sX) hybrid functional has been widely used in computational material science. Although it has widely been studied in bulk systems, less is known about its functional behavior in surface systems which are crucial to many technologies such as materials synthesis and nano-electronic devices. Assessing the screening dependent functional behaviors in the surface systems is therefore important for its application in such systems. In this work, we investigate the screening effects of the sX in CO adsorption on Pt(111) surface. The differences between the sX and Heyd-Scuseria-Ernzerhof (HSE06) hybrid functionals, and the effects of screening parameters are studied.more » The screening has two effects: first, the HOMO-LUMO gap is screening dependent. This affects the site preference most significantly. In this work, atop adsorption of CO/Pt(111) is predicted by the hybrid functionals with screened exchange potential. The sX(1.44) gives the largest HOMO-LUMO gap for the isolated CO molecule. The adsorption energy difference between the atop and fcc site is also the largest by the sX(1.44) which is explained by the reduced metal d states to the CO 2π* state back-donation, with stronger effect for the fcc adsorption than for the atop adsorption; second, the adsorption energy is screening dependent. This can be seen by comparing the sX(2.38) and HSE06 which have different screening strengths. They show similar surface band structures for the CO adsorption but different adsorption energies, which is explained by the stronger CO 5σ state to the metal d states donation or the effectively screened Pauli repulsion. This work underlines the screening strength as a main difference between sX and HSE06, as well as an important hybrid functional parameter for surface calculation.« less

IFNγ inhibits G-CSF induced neutrophil expansion and invasion of the CNS to prevent viral encephalitis

PubMed Central

Ramakrishna, Chandran

2018-01-01

Emergency hematopoiesis facilitates the rapid expansion of inflammatory immune cells in response to infections by pathogens, a process that must be carefully regulated to prevent potentially life threatening inflammatory responses. Here, we describe a novel regulatory role for the cytokine IFNγ that is critical for preventing fatal encephalitis after viral infection. HSV1 encephalitis (HSE) is triggered by the invasion of the brainstem by inflammatory monocytes and neutrophils. In mice lacking IFNγ (GKO), we observed unrestrained increases in G-CSF levels but not in GM-CSF or IL-17. This resulted in uncontrolled expansion and infiltration of apoptosis-resistant, degranulating neutrophils into the brainstem, causing fatal HSE in GKO but not WT mice. Excessive G-CSF in GKO mice also induced granulocyte derived suppressor cells, which inhibited T-cell proliferation and function, including production of the anti-inflammatory cytokine IL-10. Unexpectedly, we found that IFNγ suppressed G-CSF signaling by increasing SOCS3 expression in neutrophils, resulting in apoptosis. Depletion of G-CSF, but not GM-CSF, in GKO mice induced neutrophil apoptosis and reinstated IL-10 secretion by T cells, which restored their ability to limit innate inflammatory responses resulting in protection from HSE. Our studies reveals a novel, complex interplay among IFNγ, G-CSF and IL-10, which highlights the opposing roles of G-CSF and IFNγ in regulation of innate inflammatory responses in a murine viral encephalitis model and reveals G-CSF as a potential therapeutic target. Thus, the antagonistic G-CSF-IFNγ interactions emerge as a key regulatory node in control of CNS inflammatory responses to virus infection. PMID:29352287

Involvement of TLR2 and TLR9 in the anti-inflammatory effects of chlorogenic acid in HSV-1-infected microglia.

PubMed

Guo, Yuan-Jin; Luo, Tao; Wu, Fei; Mei, Yuan-Wu; Peng, Jun; Liu, Huan; Li, Hua-Rong; Zhang, Shu-Ling; Dong, Ji-Hua; Fang, Yuan; Zhao, Lei

2015-04-15

There is no effective medication to date for herpes simplex virus encephalitis (HSE). In this study, we investigated the anti-inflammatory effect of chlorogenic acid (CGA) on herpes simplex virus (HSV)-1-induced responses in BV2 microglia. The cellular model was established with BV2 cells stimulated by HSV-1 and then treated with CGA at different concentrations. Cell viability was assayed by the MTT assay. The mRNA expression of Toll-like receptor (TLR)-2, TLR9 and myeloid differentiation factor88 (Myd88) was assayed by real-time quantitative PCR, and the protein expression was assayed by flow cytometry or Western blotting. Tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 were measured by ELISA as well as real-time quantitative PCR. Nuclear NF-κB p65 protein was assayed by Western blotting. The cell survival rate was significantly improved after CGA treatment, and CGA prevented increases in TLR2, TLR9 and Myd88 following HSV-1 challenge in BV2 cells both at the mRNA and protein levels. Moreover, CGA could attenuate HSV-induced TNF-α and IL-6 release into the supernatant. The mRNA levels of TNF-α and IL-6 were also significantly inhibited by CGA. The expression of NF-κB p65 increased significantly in the nucleus in HSV-1-stimulated microglia but could be reduced by CGA. CGA inhibits the inflammatory reaction in HSE via the suppression of TLR2/TLR9-Myd88 signaling pathways. CGA may serve as an anti-inflammatory agent and provide a new strategy for treating HSE. Copyright © 2015 Elsevier Inc. All rights reserved.

A discussion of the links between solar variability and high-storm-surge events in Venice

NASA Astrophysics Data System (ADS)

Barriopedro, David; GarcíA-Herrera, Ricardo; Lionello, Piero; Pino, Cosimo

2010-07-01

This study explores the long-term frequency variability of high-surge events (HSEs) in the North Adriatic, the so-called acqua alta, which, particularly during autumn, cause flooding of the historical city center of Venice. The period 1948-2008, when hourly observations of sea level are available, is considered. The frequency of HSEs is correlated with the 11 year solar cycle, solar maxima being associated with a significant increase in the October-November-December HSE frequency. The seasonal geopotential height pattern at 1000 hPa (storm surge pattern; SSP) associated with the increased frequency of HSEs is identified for the whole time period and found to be similar to the positive phase of the main variability mode of the regional atmospheric circulation (empirical orthogonal function 1; EOF1). However, further analysis indicates that solar activity modulates the spatial patterns of the atmospheric circulation (EOF) and the favorable conditions for HSE occurrence (SSP). Under solar maxima, the occurrence of HSEs is enhanced by the main mode of regional atmospheric variability, namely, a large-scale wave train pattern that is symptomatic of storm track paths over northern Europe. Solar minima reveal a substantially different and less robust SSP, consisting of a meridionally oriented dipole with a preferred southward path of storm track activity, which is not associated with any dominant mode of atmospheric variability during low-solar periods. It is concluded that solar activity plays an indirect role in the frequency of HSEs by modulating the spatial patterns of the main modes of atmospheric regional variability, the favorable patterns for HSE occurrence, and their mutual relationships, so that constructive interaction between them is enhanced during solar maxima and inhibited in solar minima.

Validity of the HSE stress tool: an investigation within four organizations by the Corporate Health and Performance Group.

PubMed

Main, Chris; Glozier, Nicholas; Wright, Ian

2005-05-01

To examine the validity and accuracy of the HSE Management Standards Stress Tool. A cross-sectional questionnaire was administered to employees of the occupational health and human resource departments of four of the Corporate Health and Performance Group organizations. The relationship between the six first-pass stress filter questions and self-rated health were examined using the General Health Questionnaire (GHQ12) and the Short Form. The relationship between the filter questions and objective work characteristics such as sickness absence, self-rated performance and job satisfaction was also examined. Two hundred and thirty-five employees participated, giving an overall response rate of 68%. The study sample met the proposed HSE of 85 and 65% pass rates and would not normally progress to further analysis. Almost 40% of the group were above threshold on the GHQ12; 19% rated their work as very or extremely stressful. While the filters were highly specific, they were insensitive and at best detected for less than 40% of those with psychological or work stress. All but one of the filters had less than 50% positive predictive value for work stress and the majority of those identified by the filters did not consider themselves stressed, either overall or by work. Five of the filter questions were significantly associated with self-rated performance, three with absence and two with other objective work indicators. Further developmental work on these filter questions is indicated. Use of work absence as a measure of the impact or 'cost' of stress may lead to a significant underestimation of the 'true cost' of psychosocial hazards in the workplace.

Comparison of quartz standards for X-ray diffraction analysis: HSE A9950 (Sikron F600) and NIST SRM 1878.

PubMed

Chisholm, Jim

2005-06-01

A further comparison of the Health and Safety Executive (HSE) standard quartz, A9950 (Sikron F600), and the National Institute of Standards and Technology (NIST) Standard Reference Material (SRM) 1878, standard respirable alpha-quartz, has been carried out for the four principal diffraction peaks. In the earlier comparison by Jeyaratnam and Nagar (1993, Ann Occup Hyg; 37: 167-79), the standards were both treated in ways which might change the particle size distribution and therefore the proportion of crystalline quartz. The two standards have now been compared in the most direct way possible with the minimum of sample treatment. There are no significant differences in the diffraction peak positions for the two standards. Nor do the peak area intensities differ significantly. The peak height intensities are consistently and significantly higher for Sikron F600 than for NIST SRM 1878. The particle size broadening of the diffraction peaks is evidently greater for NIST 1878, whose mass median diameter is quoted as 1.6 microm against 2.6 microm for Sikron F600. Taking the certified reference value for SRM 1878 as 95.5 +/- 1.1% crystalline quartz, the HSE standard A9950 (Sikron F600) contains 96.3 +/- 1.4% crystalline quartz based on a comparison of peak area intensities. On the same basis but using peak height intensities, the nominal crystalline quartz content of A9950 (Sikron F600) is 101.2 +/- 1.8%. Results obtained by comparison of quartz standards may not be generally applicable because of the effect of sample treatment on particle size and crystalline quartz content.

Mind Operational Semantics and Brain Operational Architectonics: A Putative Correspondence

PubMed Central

Benedetti, Giulio; Marchetti, Giorgio; Fingelkurts, Alexander A; Fingelkurts, Andrew A

2010-01-01

Despite allowing for the unprecedented visualization of brain functional activity, modern neurobiological techniques have not yet been able to provide satisfactory answers to important questions about the relationship between brain and mind. The aim of this paper is to show how two different but complementary approaches, Mind Operational Semantics (OS) and Brain Operational Architectonics (OA), can help bridge the gap between a specific kind of mental activity—the higher-order reflective thought or linguistic thought—and brain. The fundamental notion that allows the two different approaches to be jointly used under a common framework is that of operation. According to OS, which is based on introspection and linguistic data, the meanings of words can be analyzed in terms of elemental mental operations (EOMC), amongst which those of attention play a key role. Linguistic thought is made possible by special kinds of elements, which OS calls “correlators”, which have the function of tying together the other elements of thought, which OS calls “correlata” (a "correlational network” that is, a sentence, is so formed). Therefore, OS conceives of linguistic thought as a hierarchy of operations of increasing complexity. Likewise, according to OA, which is based on the joint analysis of cognitive and electromagnetic data (EEG and MEG), every conscious phenomenon is brought to existence by the joint operations of many functional and transient neuronal assemblies in the brain. According to OA, the functioning of the brain is always operational (made up of operations), and its structure is characterized by a hierarchy of operations of increasing complexity: single neurons, single assemblies of neurons, synchronized neuronal assemblies or Operational Modules (OM), integrated or complex OMs. The authors put forward the hypothesis that the whole level of OS’s description (EOMC, correlators, and correlational networks) corresponds to the level of OMs (or set of them) of different complexity within OA’s theory: EOMC could correspond to simple OMs, correlators to complex OMs and the correlational network to a set of simple and complex OMs. Finally, a set of experiments is proposed to verify the putative correspondence between OS and OA and prove the existence of an integrated continuum between brain and mind. PMID:21113277

Metal-free inorganic ligands for colloidal nanocrystals: S2-, HS-, Se2-, HSe-, Te2-, HTe-, TeS3(2-), OH-, and NH2- as surface ligands.

PubMed

Nag, Angshuman; Kovalenko, Maksym V; Lee, Jong-Soo; Liu, Wenyong; Spokoyny, Boris; Talapin, Dmitri V

2011-07-13

All-inorganic colloidal nanocrystals were synthesized by replacing organic capping ligands on chemically synthesized nanocrystals with metal-free inorganic ions such as S(2-), HS(-), Se(2-), HSe(-), Te(2-), HTe(-), TeS(3)(2-), OH(-) and NH(2)(-). These simple ligands adhered to the NC surface and provided colloidal stability in polar solvents. The versatility of such ligand exchange has been demonstrated for various semiconductor and metal nanocrystals of different size and shape. We showed that the key aspects of Pearson's hard and soft acids and bases (HSAB) principle, originally developed for metal coordination compounds, can be applied to the bonding of molecular species to the nanocrystal surface. The use of small inorganic ligands instead of traditional ligands with long hydrocarbon tails facilitated the charge transport between individual nanocrystals and opened up interesting opportunities for device integration of colloidal nanostructures.

The application of consequence models in risk assessment: A regulator`s view

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nussey, C.; Carter, D.A.; Cassidy, K.

1995-12-31

Quantified risk assessment (QRA) is a technique for aiding decision making. The UK Health and Safety Executive (HSE) uses QRA in the Major Hazards (MH) area to formulate advice to Local Planning Authorities (LPAs) on the siting of MH installations and the development of land in the vicinity of existing MH installations. The region around UK MH sites within which LPAs are required to consult HSE on land-use planning matters (i.e. the Consultation Distance (CD)) is increasingly being redefined by adopting a risk based approach. The authors are now in the process of conducting or updated site specific QRAs tomore » redefine CDs. This process enables them to identify risk reduction measures and discuss them with companies, taking into consideration the ALARP--as low as is reasonably practicable--philosophy. The paper outlines the basis of the QRAs and the role of consequence assessment models and procedures in this process, and illustrates by examples the setting of CDs and the application of the ALARP philosophy.« less

The Sunyaev-Zeldovich Effect in Abell 370

NASA Technical Reports Server (NTRS)

Grego, Laura; Carlstrom, John E.; Joy, Marshall K.; Reese, Erik D.; Holder, Gilbert P.; Patel, Sandeep; Cooray, Asantha R.; Holzappel, William L.

2000-01-01

We present interferometric measurements of the Sunyaev-Zeldovich (SZ) effect toward the galaxy cluster Abell 370. These measurements, which directly probe the pressure of the cluster's gas, show the gas distribution to be strongly aspherical, as do the X-ray and gravitational lensing observations. We calculate the cluster's gas mass fraction in two ways. We first compare the gas mass derived from the SZ measurements to the lensing-derived gravitational mass near the critical lensing radius. We also calculate the gas mass fraction from the SZ data by deprojecting the three-dimensional gas density distribution and deriving the total mass under the assumption that the gas is in hydrostatic equilibrium (HSE). We test the assumptions in the HSE method by comparing the total cluster mass implied by the two methods and find that they agree within the errors of the measurement. We discuss the possible system- atic errors in the gas mass fraction measurement and the constraints it places on the matter density parameter, Omega(sub M).

US voluntary SEMP initiative: Holy grail or poisoned chalice?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Powell, T.A.F.

1996-12-31

There are acknowledged differences in the regulation of offshore E and P safety by the US Minerals Management Service and the UK Health and Safety Executive. The US is part of the way through a patient reform of its contemporary rules while the UK has almost completed the installation of a radically new and forceful regime. Because both regulators share a common key aim, this paper explores the background to the status quo by going back to the beginning of this century to track oilfield and regulatory development on both sides of the Atlantic. The closing part of the papermore » identifies the nature of the current divide between the UK and US positions, which were once so close. At a time of consolidation for the HSE and a time of looking into the future for MMS, the author speculates, at the close, on how the HSE might have responded to the choices confronting the MMS.« less

Behaviors of transmutation elements Re and Os and their effects on energetics and clustering of vacancy and self-interstitial atoms in W

NASA Astrophysics Data System (ADS)

Li, Yu-Hao; Zhou, Hong-Bo; Jin, Shuo; Zhang, Ying; Deng, Huiqiu; Lu, Guang-Hong

2017-04-01

We investigate the behaviors of rhenium (Re) and osmium (Os) and their interactions with point defects in tungsten (W) using a first-principles method. We show that Re atoms are energetically favorable to disperse separately in bulk W due to the Re-Re repulsive interaction. Despite the attractive interaction between Os atoms, there is still a large activation energy barrier of 1.10 eV at the critical number of 10 for the formation of Os clusters in bulk W based on the results of the total nucleation free energy change. Interestingly, the presence of vacancy can significantly reduce the total nucleation free energy change of Re/Os clusters, suggesting that vacancy can facilitate the nucleation of Re/Os in W. Re/Os in turn has an effect on the stability of the vacancy clusters (V n ) in W, especially for small vacancy clusters. A single Re/Os atom can raise the total binding energies of V2 and V3 obviously, thus enhancing their formation. Further, we demonstrate that there is a strong attractive interaction between Re/Os and self-interstitial atoms (SIAs). Re/Os could increase the diffusion barrier of SIAs and decrease their rotation barrier, while the interstitial-mediated path may be the optimal diffusion path of Re/Os in W. Consequently, the synergistic effect between Re/Os and point defects plays a key role in Re/Os precipitation and the evolution of defects in irradiated W.

Osmium isotope evidence for uniform distribution of s- and r-process components in the early solar system

NASA Astrophysics Data System (ADS)

Yokoyama, Tetsuya; Rai, Vinai K.; Alexander, Conel M. O'D.; Lewis, Roy S.; Carlson, Richard W.; Shirey, Steven B.; Thiemens, Mark H.; Walker, Richard J.

2007-07-01

We have precisely measured Os isotopic ratios in bulk samples of five carbonaceous, two enstatite and two ordinary chondrites, as well as the acid-resistant residues of three carbonaceous chondrites. All bulk meteorite samples have uniform 186Os/ 188Os, 188Os/ 189Os and 190Os/ 189Os ratios, when decomposed by an alkaline fusion total digestion technique. These ratios are also identical to estimates for Os in the bulk silicate Earth. Despite Os isotopic homogeneity at the bulk meteorite scale, acid insoluble residues of three carbonaceous chondrites are enriched in 186Os, 188Os and 190Os, isotopes with major contributions from stellar s-process nucleosynthesis. Conversely, these isotopes are depleted in acid soluble portions of the same meteorites. The complementary enriched and depleted fractions indicate the presence of at least two types of Os-rich components in these meteorites, one enriched in Os isotopes produced by s-process nucleosynthesis, the other enriched in isotopes produced by the r-process. Presolar silicon carbide is the most probable host for the s-process-enriched Os present in the acid insoluble residues. Because the enriched and depleted components present in these meteorites are combined in proportions resulting in a uniform chondritic/terrestrial composition, it requires that disparate components were thoroughly mixed within the solar nebula at the time of the initiation of planetesimal accretion. This conclusion contrasts with evidence from the isotopic compositions of some other elements (e.g., Sm, Nd, Ru, Mo) that suggests heterogeneous distribution of matter with disparate nucleosynthetic sources within the nebula.

Paleoceanographic conditions on the São Paulo Ridge, SW Atlantic Ocean, for the past 30 million years inferred from Os and Pb isotopes of a hydrogenous ferromanganese crust

NASA Astrophysics Data System (ADS)

Goto, Kosuke T.; Nozaki, Tatsuo; Toyofuku, Takashi; Augustin, Adolpho H.; Shimoda, Gen; Chang, Qing; Kimura, Jun-Ichi; Kameo, Koji; Kitazato, Hiroshi; Suzuki, Katsuhiko

2017-12-01

Hydrogenous ferromanganese (Fe-Mn) crusts can provide records of long-term environmental changes during the Cenozoic. To understand the paleoceanographic conditions in the southwestern Atlantic Ocean, we investigated depth profiles of major- and trace-element concentrations as well as Os and Pb isotopic compositions in a Fe-Mn crust collected from the southern flank of the São Paulo Ridge in the southwestern Atlantic. Major and trace element data plotted on ternary Mn-Fe-10×(Ni+Co+Cu) and rare-earth element plus yttrium (REY) discrimination diagrams indicate that the analyzed sample is a typical hydrogenous Fe-Mn crust. The obtained 187Os/188Os data were matched to the Cenozoic seawater Os isotope evolution curve reconstructed from pelagic sediments. The result suggests that the Fe-Mn crust has accreted over 30 Myr with growth rates of 0.5-3 mm/Myr, although the sample likely grew in two directions during the early stage of its growth. We found no evidence of growth hiatus in the sample, which may contrast with the growth histories of many Pacific Fe-Mn crusts. Hence, the conditions favorable for the accretion of hydrogenous Fe-Mn crusts were likely to have developed on the São Paulo Ridge over the past 30 Myr. The Pb isotopic compositions show very limited ranges (e.g., 206Pb/204Pb=18.80-18.85), and are similar to those of pre-anthropogenic seawater in the Southern Ocean. As the São Paulo Ridge is located near the Vema Channel, which is presently a major path of Antarctic Bottom Water, we suggest that a strong northward bottom current has continuously swept detrital and biogenic sediments from the ridge, and played a vital role in the Fe-Mn crust formation since 30 Ma.

Development and validation of an ICP-OES method for quantitation of elemental impurities in tablets according to coming US pharmacopeia chapters.

PubMed

Støving, Celina; Jensen, Henrik; Gammelgaard, Bente; Stürup, Stefan

2013-10-01

May 1, 2014 the United States Pharmacopeia (USP) will implement two new chapters stating limit concentrations of elemental impurities in pharmaceuticals applying inductively coupled plasma methods. In the present work an inductively coupled plasma optical emission spectrometry (ICP-OES) method for quantitation of As, Cd, Cu, Cr, Fe, Hg, Ir, Mn, Mo, Ni, Os, Pb, Pd, Pt, Rh, Ru, V and Zn in tablets according to the new USP chapters was developed. Sample preparation was performed by microwave-assisted acid digestion using a mixture of 65% HNO3 and 37% HCl (3:1, v/v). Limits of detection and quantitation were at least a factor of ten below the USP limit concentrations showing that the ICP-OES technique is well suited for quantitation of elemental impurities. Excluding Os, spike recoveries in the range of 85.3-103.8% were obtained with relative standard deviations (%RSD) ranging from 1.3 to 3.2%. Due to memory effects the spike recovery and %RSD of Os were 161.5% and 13.7%, respectively, thus the method will need further development with respect to elimination of the memory effect of Os. The method was proven to be specific but with potential spectral interference for Ir, Os, Pb, Pt and Rh necessitating visual examination of the spectra. Hg memory effect was handled by using lower spike levels combined with rinsing with 0.1M HCl. The tablets had a content of Fe and Pt of 182.8 ± 18.1 and 2.8 ± 0.2 μg/g, respectively and did therefore not exceed the limit concentration defined by USP. It is suggested that the developed method is applicable to pharmaceutical products with a composition and maximal amount of daily intake (g drug product/day) similar to the tablets used in this work. Copyright © 2013 Elsevier B.V. All rights reserved.

Molecular characterization of heat shock protein 70 (HSP 70) promoter in Japanese flounder (Paralichthys olivaceus), and the association of Pohsp70 SNPs with heat-resistant trait.

PubMed

Qi, Jie; Liu, Xudong; Liu, Jinxiang; Yu, Haiyang; Wang, Wenji; Wang, Zhigang; Zhang, Quanqi

2014-08-01

Ambient temperature is one of the major abiotic environmental factors determining the main parameters of fish vital activity. HSP70 plays an essential role in heat response. In this investigation, the promoter and structure of Paralichthys olivaceus hsp70 (Pohsp70) gene was cloned and predicted. 2558 bp upstream regulatory region of Pohsp70 was annotated with four potential promoter elements and four putative binding sites of transcription factors heat shock elements (HSE, nGAAn) in the upstream of the transcription start site. In addition, one intron with 454 bp in the 5'-noncoding region was found. Quantitative Real Time PCR analysis indicated that the transcript level of Pohsp70 was raised markedly after 1 h by heat shocked. Furthermore, 25 SNPs were identified in Pohsp70 by resequencing, seven of which was associated with heat resistance. In addition, two of the seven SNPs, namely SNP14 and SNP16, were observed in strong linkage disequilibrium. The haplotype with association analysis showed TAGGAG haplotype was more represented in heat susceptible group while (DEL/T) GAATA haplotype was more frequent in heat resistant group. The heat resistant SNPs and haplotype could be candidate markers potentially serving for selective breeding programs of Japanese flounder aimed at improving anti-stress and production. Copyright © 2014 Elsevier Ltd. All rights reserved.

HSF and Msn2/4p can exclusively or cooperatively activate the yeast HSP104 gene.

PubMed

Grably, Melanie R; Stanhill, Ariel; Tell, Osnat; Engelberg, David

2002-04-01

In an effort to understand how an accurate level of stress-specific expression is obtained, we studied the promoter of the yeast HSP104 gene. Through 5' deletions, we defined a 334 bp fragment upstream of the first coding AUG as sufficient and essential for maximal basal activity and a 260 bp fragment as sufficient and essential for heat shock responsiveness. These sequences contain heat shock elements (HSEs) and stress response elements (STREs) that cooperate to achieve maximal inducible expression. However, in the absence of one set of factors (e.g. in msn2Deltamsn4Delta cells) proper induction is obtained exclusively through HSEs. We also show that HSP104 is constitutively derepressed in ras2Delta cells. This derepression is achieved exclusively through activation of STREs, with no role for HSEs. Strikingly, in ras2Deltamsn2Deltamsn4Delta cells the HSP104 promoter is also derepressed, but in this strain derepression is mediated through HSEs, showing the flexibility and adaptation of the promoter. Thus, appropriate transcription of HSP104 is usually obtained through cooperation between the Msn2/4/STRE and the HSF/ HSE systems, but each factor could activate the promoter alone, backing up the other. Transcription control of HSP104 is adaptive and robust, ensuring proper expression under extreme conditions and in various mutants.

Composition of the earth's upper mantle-I. Siderophile trace elements in ultramafic nodules

USGS Publications Warehouse

Morgan, J.W.; Wandless, G.A.; Petrie, R.K.; Irving, A.J.

1981-01-01

Seven siderophile elements (Au, Ge, Ir, Ni, Pd, Os, Re) were determined by radiochemical neutron activation analysis in 19 ultramafic rocks, which are spinel lherzollites-xenoliths from North and Central America, Hawaii and Australia, and garnet Iherzolitexenoliths from Lesotho. Abundances of the platinum metals are very uniform in spinel lherzolites averaging 3.4 ?? 1.2 ppb Os, 3.7 ?? 1.1 ppb Ir, and 4.6 ?? 2.0 ppb Pd. Sheared garnet lherzolite PHN 1611 has similar abundances of these elements, but in 4 granulated garnet lherzolites, abundances are more variable. In all samples, the Pt metals retain cosmic ( Cl-chondrite) ratios. Abundances of Au and Re vary more than those of Pt metals, but the Au/Re ratio remains close to the cosmic value. The fact that higher values of Au and Re approach cosmic proportions with respect to the Pt metals, suggests that Au and Re have been depleted in some ultramafic rocks from an initially chondrite-like pattern equivalent to about 0.01 of Cl chondrite abundances. The relative enrichment of Au and Re in crustal rocks is apparently the result of crust-mantle fractionation and does not require a special circumstance of core-mantle partitioning. Abundances of moderately volatile elements Ni, Co and Ge are very uniform in all rocks, and are much higher than those of the highly siderophile elements Au, Ir, Pd, Os and Re. When normalized to Cl chondrites, abundances of Ni and Co are nearly identical, averaging 0.20 ?? 0.02 and 0.22 ?? 0.02, respectively; but Ge is only 0.027 ?? 0.004. The low abundance of Ge relative to Ni and Co is apparently a reflection of the general depletion of volatile elements in the Earth. The moderately siderophile elements cannot be derived from the same source as the highly siderophile elements because of the marked difference in Cl chondrite-normalized abundances and patterns. We suggest that most of the Ni, Co and Ge were enriched in the silicate by the partial oxidation of pre-existing volatile-poor Fe-Ni, whereas the corresponding highly siderophile elements remained sequestered by the surviving metal. The highly siderophile elements may have been introduced by a population of ~103 large (~1022 g) planetisimals, similar to those forming the lunar mare basins. ?? 1981.

Generalised and abdominal adiposity are important risk factors for chronic disease in older people: results from a nationally representative survey.

PubMed

Hirani, V

2011-06-01

To look at the trends in prevalence of generalised (body mass index (BMI) ≥ 25 kg/m2) and abdominal obesity (waist circumference (WC) >102 cm, men; > 88 cm, women) among older people from 1993 to 2008, prevalence of chronic disease by overweight/obesity and WC categories in England 2005 and evaluate the association of these measures with chronic diseases. Analyses of nationally representative cross-sectional population surveys, the Health Survey for England (HSE). Non-institutionalised men and women aged ≥ 65 years (in HSE 2005, 1512 men and 1747 women). Height, weight, waist circumference, blood pressure measurements were taken according to standardised HSE protocols. Information collected on socio-demographic, health behaviour and doctor diagnosed health conditions. Generalised obesity and abdominal obesity increased among men and women from 1993 to 2008. In 2005, the HSE 2005 focussed on older people. 72% of men and 68% of women aged over 65 were either overweight or obese. Prevalence of raised WC was higher in women (58%) than in men (46%). The prevalence of diabetes and arthritis was higher in people with generalised obesity in both sexes. Men were more likely to have had a joint replacement and had a higher prevalence of stroke if they were overweight only but women were more likely to have had a joint replacement only if they were obese (13%) and had a higher risk of falls with generalised obesity. The pattern was similar for the prevalence of chronic diseases by raised WC. Multivariate analysis showed that generalised and abdominal obesity was independently associated with risk of hypertension, diabetes and arthritis in both men and women. In women only, there was an association between generalised obesity and having a fall in the last year (OR: 1.5), and between abdominal obesity and having a joint replacement (OR: 1.9, p=0.01). Complications of obesity such as diabetes, hypertension and arthritis, are more common in men and women aged over 65 who are overweight or obese, as well as in those with a raised WC. These conditions impact on morbidity, mortality and have cost implications for the health service and are known to improve with weight loss even in old age. Treatment strategies to address these conditions such as weight management and prevention of overweight and obesity are important even in older people. There is a need to ensure that older people are given appropriate advice about keeping physically active and eating sensibly.

Distribution of siderophile and other trace elements in melt rock at the Chicxulub impact structure

NASA Technical Reports Server (NTRS)

Schuraytz, B. C.; Lindstrom, D. J.; Martinez, R. R.; Sharpton, V. L.; Marin, L. E.

1994-01-01

Recent isotopic and mineralogical studies have demonstrated a temporal and chemical link between the Chicxulub multiring impact basin and ejecta at the Cretaceous-Tertiary boundary. A fundamental problem yet to be resolved, however, is identification of the projectile responsible for this cataclysmic event. Drill core samples of impact melt rock from the Chichxulub structure contain Ir and Os abundances and Re-Os isotopic ratios indicating the presence of up to approx. 3 percent meteoritic material. We have used a technique involving microdrilling and high sensitivity instrumental neutron activation analysis (INAA) in conjunction with electron microprobe analysis to characterize further the distribution of siderophile and other trace elements among phases within the C1-N10 melt rock.

Refractory inclusions with unusual chemical compositions from the Vigarano carbonaceous chondrite

NASA Technical Reports Server (NTRS)

Sylvester, Paul J.; Grossman, Lawrence; Macpherson, Glenn J.

1992-01-01

Neutron activation was used to test ten inclusions, nine Vigarano and one from Leoville, for major and trace elements. Six Vigarano refractory inclusions have refractory element fractionations that are rare or absent in Allende inclusions. Vig 1623-11 has Th/La and Ir/Mo ratios that are lower than those of any Allende Group I or modified Group I inclusions, and Os/La, Ir/La, and Zr/Hf ratios that are among the lowest in those inclusions. The low Os/La, Ir/La, and Ir/Mo ratios seem to require nonrepresentative sampling of condensate phase in the nebula to a degree that is usual for Allende Group I and modified group I inclusions. The nature and origins of the different inclusions are discussed.

Authentication of Kalix (N.E. Sweden) vendace caviar using inductively coupled plasma-based analytical techniques: evaluation of different approaches.

PubMed

Rodushkin, I; Bergman, T; Douglas, G; Engström, E; Sörlin, D; Baxter, D C

2007-02-05

Different analytical approaches for origin differentiation between vendace and whitefish caviars from brackish- and freshwaters were tested using inductively coupled plasma double focusing sector field mass spectrometry (ICP-SFMS) and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). These approaches involve identifying differences in elemental concentrations or sample-specific isotopic composition (Sr and Os) variations. Concentrations of 72 elements were determined by ICP-SFMS following microwave-assisted digestion in vendace and whitefish caviar samples from Sweden (from both brackish and freshwater), Finland and USA, as well as in unprocessed vendace roe and salt used in caviar production. This data set allows identification of elements whose contents in caviar can be affected by salt addition as well as by contamination during production and packaging. Long-term method reproducibility was assessed for all analytes based on replicate caviar preparations/analyses and variations in element concentrations in caviar from different harvests were evaluated. The greatest utility for differentiation was demonstrated for elements with varying concentrations between brackish and freshwaters (e.g. As, Br, Sr). Elemental ratios, specifically Sr/Ca, Sr/Mg and Sr/Ba, are especially useful for authentication of vendace caviar processed from brackish water roe, due to the significant differences between caviar from different sources, limited between-harvest variations and relatively high concentrations in samples, allowing precise determination by modern analytical instrumentation. Variations in the 87Sr/86Sr ratio for vendace caviar from different harvests (on the order of 0.05-0.1%) is at least 10-fold less than differences between caviar processed from brackish and freshwater roe. Hence, Sr isotope ratio measurements (either by ICP-SFMS or by MC-ICP-MS) have great potential for origin differentiation. On the contrary, it was impossible to differentiate between Swedish caviar processed from brackish water roe and Finnish freshwater caviar based solely on 187Os/188Os ratios.

Conservation of Chitin-Induced MAPK Signaling Pathways in Rice and Arabidopsis.

PubMed

Yamada, Kenta; Yamaguchi, Koji; Yoshimura, Satomi; Terauchi, Akira; Kawasaki, Tsutomu

2017-06-01

Perception of microbe-associated molecular patterns (MAMPs) including chitin by pattern recognition receptors (PRRs) rapidly induces activation of mitogen-activated protein kinase (MAPK) cascades. However, how PRRs transmit immune signals to the MAPK cascade is largely unknown. Recently, Arabidopsis receptor-like cytoplasmic kinase PBL27 has been reported to activate MAPKs through phosphorylation of AtMAPKKK5 in the chitin signaling pathway. In this study, we found that OsRLCK185, a rice ortholog of PBL27, regulates chitin-induced MAPK activation in a similar fashion to PBL27 in rice. Upon chitin perception, OsRLCK185 is phosphorylated by OsCERK1, a component of the chitin receptor complex. OsRLCK185 interacted with OsMAPKKK11 and OsMAPKKK18, rice orthologs of AtMAPKKK5, in yeast two-hybrid assays. Silencing of both OsMAPKKK11 and OsMAPKKK18 significantly reduced chitin-induced activation of OsMPK3 and OsMPK6. Expression levels of OsMAPKKK18 were much higher than that of OsMAPKKK11 in rice cells, which was consistent with the fact that the Osmapkkk11 single mutation did not affect MAPK activation. This result suggested that OsMAPKKK18 plays a more important role than OsMAPKKK11 in the chitin-induced activation of OsMPK3 and OsMPK6. The bimolecular fluorescence complementation (BiFC) experiment indicated that OsRLCK185 interacted with OsMAPKKK18 at the plasma membrane in planta. In vitro phosphorylation experiments showed that OsRLCK185 directly phosphorylates OsMAPKKK18. Furthermore, OsMAPKKK18 interacted with the MAPKK OsMKK4, the upstream component of OsMPK3/6. These results suggested that OsRLCK185 connects the chitin receptor to the MAPK cascade consisting of OsMAPKKK18-OsMKK4-OsMPK3/6. Our data revealed that chitin-induced MAPK activation in rice and Arabidopsis is regulated by common homologous elements. © The Author 2017. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Surface-Cycling of Rhenium and its Isotopes

DTIC Science & Technology

2009-06-01

Fisher Scientific) in the WHOI plasma facility. Samples were introduced using a PFA MicroFlow nebulizer (Elemental Scientific Incorporated), a quartz...Samples were introduced using a PFA MicroFlow nebulizer (Elemental Scientific Incorporated), a quartz spray chamber, and regular cones. Analyses are done in...189Os. Samples dissolved in 1 mL of 0.5 molL−1 HNO3 are introduced using a PFA MicroFlow nebulizer (Elemental Scientific Incorporated), a quartz spray

Large-scale implementation of enhanced recovery programs after surgery. A francophone experience.

PubMed

Veziant, J; Raspado, O; Entremont, A; Joris, J; Pereira, B; Slim, K

2017-06-01

Enhanced recovery after surgery program (ERP) has now surpassed the stage of clinical research in certain specialties and currently poses the problematic of large-scale implementation. The goal of this study was to report the experience during the first year of implementation in three French-speaking countries. This is a prospective study in which 67 healthcare centers, all registered in the Grace-Audit databank, participated. Included were patients undergoing colorectal (CRS), bariatric (BS) and orthopedic hip and knee surgery (OS), performed within an ERP. The main endpoints were duration of hospital stay, postoperative morbidity, the degree of compliance with the elements of the ERP, the relation between the extent of application of the elements and postoperative hospital stay, and finally the completeness of data inclusions in the databank. A total of 1904 patients were included in the Grace-Audit databank between January 1, 2015 and January 31, 2016, undergoing CRS (n=490), BS (n=431), and OS (n=983). The mean implementation rate was 83.7±10.0% for CRS, 75.0±23.7% for BS, and 83.5±14.9% for OS. The duration of hospital stay was 6.5 days for CRS, 2.6 days for BS and 3.4 days for OS. Overall postoperative morbidity (onset of postoperative undesirable event), surgical morbidity (superficial or deep organ space surgical site complications such as bleeding, infection or defective healing) and readmission rates were 20.6%, 7.5%, and 5.7% for CRS; 2.5%, 1.4%, and 1.6% for BS and 2.9%, 0.2%, and 2% for OS, respectively. A statistically significant relationship was found between the degree of compliance of the elements of ERP and the duration of hospital stay for CRS and BS; hospital stay was reduced when at least 15 of the 22 elements of the program were applied (P<0.001). The patients included in the Grace-Audit databank represented less than 20% of the patients undergoing operation in the same establishments during the study period for all three specialties. This study shows that large-scale ERPs are feasible and safe in French-speaking countries. Nonetheless, although encouraging, these preliminary results highlight that implementation must be improved in specialties such as bariatric surgery and that more complete data collection is needed. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

The terrestrial late veneer from core disruption of a lunar-sized impactor

NASA Astrophysics Data System (ADS)

Genda, H.; Brasser, R.; Mojzsis, S. J.

2017-12-01

Overabundances in highly siderophile elements (HSEs) of Earth's mantle can be explained by conveyance from a singular, immense (D ∼ 3000 km) ;Late Veneer; impactor of chondritic composition, subsequent to lunar formation and terrestrial core-closure. Such rocky objects of approximately lunar mass (∼0.01 M⊕) ought to be differentiated, such that nearly all of their HSE payload is sequestered into iron cores. Here, we analyze the mechanical and chemical fate of the core of such a Late Veneer impactor, and trace how its HSEs are suspended - and thus pollute - the mantle. For the statistically most-likely oblique collision (∼45°), the impactor's core elongates and thereafter disintegrates into a metallic hail of small particles (∼10 m). Some strike the orbiting Moon as sesquinary impactors, but most re-accrete to Earth as secondaries with further fragmentation. We show that a single oblique impactor provides an adequate amount of HSEs to the primordial terrestrial silicate reservoirs via oxidation of (

Electronic structure and p-type doping of ZnSnN2

NASA Astrophysics Data System (ADS)

Wang, Tianshi; Janotti, Anderson; Ni, Chaoying

ZnSnN2 is a promising solar-cell absorber material composed of earth abundant elements. Little is known about doping, defects, and how the valence and conduction bands in this material align with the bands in other semiconductors. Using density functional theory with the the Heyd-Scuseria-Ernzerhof hybrid functional (HSE06), we investigate the electronic structure of ZnSnN2, its band alignment to other semiconductors, such as GaN and ZnO, the possibility of p-type doping, and the possible causes of the observed unintentional n-type conductivity. We find that the position of the valence-band maximum of ZnSnN2 is 0.55 eV higher than that of GaN, yet the conduction-band minimum is close to that in ZnO. As possible p-type dopants, we explore Li, Na, and K substituting on the Zn site. Finally, we discuss the cause of unintentional n-type conductivity by analyzing the position of the conduction-band minimum with respect to that of GaN and ZnO.

Electronic Structure at Electrode/Electrolyte Interfaces in Magnesium based Batteries

NASA Astrophysics Data System (ADS)

Balachandran, Janakiraman; Siegel, Donald

2015-03-01

Magnesium is a promising multivalent element for use in next generation electrochemical energy storage systems. However, a wide range of challenges such as low coulombic efficiency, low/varying capacity and cyclability need to be resolved in order to realize Mg based batteries. Many of these issues can be related to interfacial phenomena between the Mg anode and common electrolytes. Ab-initio based computational models of these interfaces can provide insights on the interfacial interactions that can be difficult to probe experimentally. In this work we present ab-initio computations of common electrolyte solvents (THF, DME) in contact with two model electrode surfaces namely -- (i) an ``SEI-free'' electrode based on Mg metal and, (ii) a ``passivated'' electrode consisting of MgO. We perform GW calculations to predict the reorganization of the molecular orbitals (HOMO/LUMO) upon contact with the these surfaces and their alignment with respect to the Fermi energy of the electrodes. These computations are in turn compared with more efficient GGA (PBE) & Hybrid (HSE) functional calculations. The results obtained from these computations enable us to qualitatively describe the stability of these solvent molecules at electrode-electrolyte interfaces

Os isotope systematics of La Palma, Canary Islands: Evidence for recycled crust in the mantle source of HIMU ocean islands

NASA Astrophysics Data System (ADS)

Marcantonio, Franco; Zindler, Alan; Elliott, Tim; Staudigel, Hubert

1995-07-01

Sub-aerial lavas from the single ocean island of La Palma, Canary Islands show as large a variation in 187Os/186Os isotope ratios (1.13-1.59) as found across all of French Polynesia [1]. The La Palma lavas, however, display a restricted range of chemical composition and have all been erupted within the last 3.5 Ma. The highest Os isotopic compositions are observed in lavas with low Os concentrations. An uplifted sequence of lavas, that represent the early phase of submarine growth of the island, show extremely heterogeneous 187Os/186Os isotope ratios, from 1.21 to 3.53, with the most radiogenic values found in pillow rinds. Assimilation of these pillow rinds by ascending magma can readily account for highly radiogenic ratios ( 187Os/186Os > 1.3 ) found in lavas with Os concentrations below 30 ppt. Samples with Os concentrations too high to be significantly affected by assimilation still display a range in Os isotope ratios from 1.13 to 1.25. We argue that these radiogenic values reflect a HIMU mantle source that contains ancient recycled oceanic crust. Characteristic incompatible trace element ratios suggest further similarities between the mantle beneath La Palma and other HIMU islands. When potentially contaminated low-Os OIBs are screened from literature data, HIMU islands are found to display the highest Os isotope ratios (up to 1.25). PbOs systematics for uncontaminated OIBs do not define a simple two-component mixing relationship between ambient mantle and recycled oceanic crust of a single composition. We suggest that this is due to variable alteration and subduction-induced perturbation of the U/Pb ratio in the recycled material that forms a component of the HIMU source.

45. MAIN MEETING ROOM COLUMNS. Ends of gallery columns identified ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

45. MAIN MEETING ROOM COLUMNS. Ends of gallery columns identified at the time of removal for transfer to the George School for re-erection. The stamp reads, 'REMOVED FROM 12th ST. MTG HSE PHILA 1972'. - Twelfth Street Meeting House, 20 South Twelfth Street, Philadelphia, Philadelphia County, PA

HSE Abundances in Angrites and HEDs: Core-Mantle Equilibration or Late Accretion Addition of a Chondritic Component

NASA Astrophysics Data System (ADS)

Rai, N.; Downes, H.; Smith, C. L.

2016-08-01

Using metal-silicate partitioning of HSEs together with their mantle abundances in Vesta and the APB respectively, we test whether formation of a metallic core could have led to the observed abundances of the HSEs, in the mantles of these bodies.

Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments

USGS Publications Warehouse

Rooney, A.D.; Selby, D.; Lewan, M.D.; Lillis, P.G.; Houzay, J.-P.

2012-01-01

Successful application of the 187Re–187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products (e.g., bitumen and oil). To more fully understand the behaviour of Re–Os systematics in both source rocks and petroleum products we apply hydrous pyrolysis to two immature hydrocarbon source rocks: the Permian Phosphoria Formation (TOC = 17.4%; Type II-S kerogen) and the Jurassic Staffin Formation (TOC = 2.5%; Type III kerogen). The laboratory-based hydrous pyrolysis experiments were carried out for 72 h at 250, 300, 325 and 350 °C. These experiments provided us with whole rock, extracted rock and bitumen and in some cases expelled oil and asphaltene for evaluation of Re–Os isotopic and elemental abundance. The data from these experiments demonstrate that the majority (>95%) of Re and Os are housed within extracted rock and that thermal maturation does not result in significant transfer of Re or Os from the extracted rock into organic phases. Based on existing thermodynamic data our findings suggest that organic chelating sites have a greater affinity for the quadravalent states of Re and Os than sulphides. Across the temperature range of the hydrous pyrolysis experiments both whole rock and extracted rock 187Re/188Os ratios show small variations (3.3% and 4.7%, for Staffin, respectively and 6.3% and 4.9% for Phosphoria, respectively). Similarly, the 187Os/188Os ratios show only minor variations for the Staffin and Phosphoria whole rock and extracted rock samples (0.6% and 1.4% and 1.3% and 2.2%). These isotopic data strongly suggest that crude oil generation through hydrous pyrolysis experiments does not disturb the Re–Os systematics in ORS as supported by various studies on natural systems. The elemental abundance data reveal limited transfer of Re and Os into the bitumen from a Type III kerogen in comparison to Type II-S kerogen (0.02% vs. 3.7%), suggesting that these metals are very tightly bound in Type III kerogen structure. The 187Os/188Os data from the pyrolysis generated Phosphoria bitumens display minor variation (4%) across the experimental temperatures, with values similar to that of the source rock. This indicates that the isotopic composition of the bitumen reflects the isotopic composition of the source rock at the time of petroleum generation. These data further support the premise that the Os isotopic composition of oils and bitumens can be used to fingerprint petroleum deposits to specific source rocks. Oil generated through the hydrous pyrolysis experiments does not contain appreciable quantities of Re or Os (~120 and ~3 ppt, respectively), in contrast to natural oils (2–50 ppb and 34–288 ppt for Re and Os, respectively), which may suggest that kinetic parameters are fundamental to the transfer of Re and Os from source rocks to oils. From this we hypothesise that, at the temperatures employed in hydrous pyrolysis, Re and Os are assimilated into the extracted rock as a result of cross-linking reactions.

Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments

NASA Astrophysics Data System (ADS)

Rooney, Alan D.; Selby, David; Lewan, Michael D.; Lillis, Paul G.; Houzay, Jean-Pierre

2012-01-01

Successful application of the 187Re-187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products (e.g., bitumen and oil). To more fully understand the behaviour of Re-Os systematics in both source rocks and petroleum products we apply hydrous pyrolysis to two immature hydrocarbon source rocks: the Permian Phosphoria Formation (TOC = 17.4%; Type II-S kerogen) and the Jurassic Staffin Formation (TOC = 2.5%; Type III kerogen). The laboratory-based hydrous pyrolysis experiments were carried out for 72 h at 250, 300, 325 and 350 °C. These experiments provided us with whole rock, extracted rock and bitumen and in some cases expelled oil and asphaltene for evaluation of Re-Os isotopic and elemental abundance. The data from these experiments demonstrate that the majority (>95%) of Re and Os are housed within extracted rock and that thermal maturation does not result in significant transfer of Re or Os from the extracted rock into organic phases. Based on existing thermodynamic data our findings suggest that organic chelating sites have a greater affinity for the quadravalent states of Re and Os than sulphides. Across the temperature range of the hydrous pyrolysis experiments both whole rock and extracted rock 187Re/188Os ratios show small variations (3.3% and 4.7%, for Staffin, respectively and 6.3% and 4.9% for Phosphoria, respectively). Similarly, the 187Os/188Os ratios show only minor variations for the Staffin and Phosphoria whole rock and extracted rock samples (0.6% and 1.4% and 1.3% and 2.2%). These isotopic data strongly suggest that crude oil generation through hydrous pyrolysis experiments does not disturb the Re-Os systematics in ORS as supported by various studies on natural systems. The elemental abundance data reveal limited transfer of Re and Os into the bitumen from a Type III kerogen in comparison to Type II-S kerogen (0.02% vs. 3.7%), suggesting that these metals are very tightly bound in Type III kerogen structure. The 187Os/188Os data from the pyrolysis generated Phosphoria bitumens display minor variation (4%) across the experimental temperatures, with values similar to that of the source rock. This indicates that the isotopic composition of the bitumen reflects the isotopic composition of the source rock at the time of petroleum generation. These data further support the premise that the Os isotopic composition of oils and bitumens can be used to fingerprint petroleum deposits to specific source rocks. Oil generated through the hydrous pyrolysis experiments does not contain appreciable quantities of Re or Os (∼120 and ∼3 ppt, respectively), in contrast to natural oils (2-50 ppb and 34-288 ppt for Re and Os, respectively), which may suggest that kinetic parameters are fundamental to the transfer of Re and Os from source rocks to oils. From this we hypothesise that, at the temperatures employed in hydrous pyrolysis, Re and Os are assimilated into the extracted rock as a result of cross-linking reactions.

A model for osmium isotopic evolution of metallic solids at the core-mantle boundary

NASA Astrophysics Data System (ADS)

Humayun, Munir

2011-03-01

Some plumes are thought to originate at the core-mantle boundary, but geochemical evidence of core-mantle interaction is limited to Os isotopes in samples from Hawaii, Gorgona (89 Ma), and Kostomuksha (2.7 Ga). The Os isotopes have been explained by physical entrainment of Earth's liquid outer core into mantle plumes. This model has come into conflict with geophysical estimates of the timing of core formation, high-pressure experimental determinations of the solid metal-liquid metal partition coefficients (D), and the absence of expected 182W anomalies. A new model is proposed where metallic liquid from the outer core is partially trapped in a compacting cumulate pile of Fe-rich nonmetallic precipitates (FeO, FeS, Fe3Si, etc.) at the top of the core and undergoes fractional crystallization precipitating solid metal grains, followed by expulsion of the residual metallic liquid back to the outer core. The Os isotopic composition of the solids and liquids in the cumulate pile is modeled as a function of the residual liquid remaining and the emplacement age using 1 bar D values, with variable amounts of oxygen (0-10 wt %) as the light element. The precipitated solids evolve Os isotope compositions that match the trends for Hawaii (at an emplacement age of 3.5-4.5 Ga; 5%-10% oxygen) and Gorgona (emplacement age < 1.5 Ga; 0%-5% oxygen). The Fe-rich matrix of the cumulate pile dilutes the precipitated solid metal decoupling the Fe/Mn ratio from Os and W isotopes. The advantages to using precipitated solid metal as the Os host include a lower platinum group element and Ni content to the mantle source region relative to excess iron, miniscule anomalies in 182W (<0.1 ɛ), and no effects for Pb isotopes, etc. A gradual thermomechanical erosion of the cumulate pile results in incorporation of this material into the base of the mantle, where mantle plumes subsequently entrain it. Fractional crystallization of metallic liquids within the CMB provides a consistent explanation of both Os isotope correlations, Os-W isotope systematics, and Fe/Mn evidence for core-mantle interaction over the entire Hawaiian source.

Volatile trace elements and the characterization of the Cayley Formation and the primitive lunar crust

NASA Technical Reports Server (NTRS)

Jovanovic, S.; Reed, G. W., Jr.

1973-01-01

Two types of highland terrain appear to be present at the Apollo 16 landing site. The Plains Formation called Cayley is ubiquitous and blankets even those regions that were presumably a part of the mountainous Descartes Formation. The second type of terrain is that associated with the ejectae from North and South Ray craters. The stratigraphy sampled by the ejectae underlays the Cayley layer as characterized above and may permit a redefinition of Descartes Formation as that which underlays the smooth Plains deposits. These conclusions are based on the concentrations and chemical coherence between elements such as Cl-F-P2O5 and Ru-Os. The primitive lunar crust may be characterized by the type of feldspathic rocks which are enriched in trace elements, such as Cl, Br, U, Te, Ru, and Os, as found in 'rusty' rock 66095 and in 61016; other feldspathic rocks are depleted and may be of secondary origin.

Dissecting the Re-Os molybdenite geochronometer.

PubMed

Barra, Fernando; Deditius, Artur; Reich, Martin; Kilburn, Matt R; Guagliardo, Paul; Roberts, Malcolm P

2017-11-22

Rhenium and osmium isotopes have been used for decades to date the formation of molybdenite (MoS 2 ), a common mineral in ore deposits and the world's main source of molybdenum and rhenium. Understanding the distribution of parent 187 Re and radiogenic daughter 187 Os isotopes in molybdenite is critical in interpreting isotopic measurements because it can compromise the accurate determination and interpretation of mineralization ages. In order to resolve the controls on the distribution of these elements, chemical and isotope mapping of MoS 2 grains from representative porphyry copper-molybdenum deposits were performed using electron microprobe and nano-scale secondary ion mass spectrometry. Our results show a heterogeneous distribution of 185,187 Re and 192 Os isotopes in MoS 2 , and that both 187 Re and 187 Os isotopes are not decoupled as previously thought. We conclude that Re and Os are structurally bound or present as nanoparticles in or next to molybdenite grains, recording a complex formation history and hindering the use of microbeam techniques for Re-Os molybdenite dating. Our study opens new avenues to explore the effects of isotope nuggeting in geochronometers.

Anthropogenic osmium in rain and snow reveals global-scale atmospheric contamination.

PubMed

Chen, Cynthia; Sedwick, Peter N; Sharma, Mukul

2009-05-12

Osmium is one of the rarer elements in seawater, with typical concentration of approximately 10 x 10(-15) g g(-1) (5.3 x 10(-14) mol kg(-1)). The osmium isotope composition ((187)Os/(188)Os ratio) of deep oceans is 1.05, reflecting a balance between inputs from continental crust (approximately 1.3) and mantle/cosmic dust (approximately 0.13). Here, we show that the (187)Os/(188)Os ratios measured in rain and snow collected around the world range from 0.16 to 0.48, much lower than expected (>1), but similar to the isotope composition of ores (approximately 0.2) that are processed to extract platinum and other metals to be used primarily in automobile catalytic converters. Present-day surface seawater has a lower (187)Os/(188)Os ratio (approximately 0.95) than deep waters, suggesting that human activities have altered the isotope composition of the world's oceans and impacted the global geochemical cycle of osmium. The contamination of the surface ocean is particularly remarkable given that osmium has few industrial uses. The pollution may increase with growing demand for platinum-based catalysts.

Osmium isotopes in Ivory Coast tektites: Confirmation of a meteoritic component and rhenium depletion

NASA Technical Reports Server (NTRS)

Koeberl, Christian; Shirey, Steven B.

1993-01-01

The sensitive negative thermal ionization mass spectrometry method was used for the measurement of concentrations and isotopic ratios of osmium and rhenium in four Ivory Coast tektites. These tektites have crustal major and trace element composition, as well as large negative epsilon(sub Nd)(-20) and positive epsilon(sub Sr)(+260 to +300) which are characteristic for old continental crust. Os concentrations ranging from 0.09 to 0.30 ppb were found, clearly much higher than average crustal values, Os-187/Os-186 ratios of about 1.2-1.7, and low Re-187/Os-186 ratios. These results show unambiguously the existence of a meteoritic component (on the order of 0.06%) in the Ivory Coast tektites. Low Re abundances are the result of fractionation of Re during the impact.

Comparative Study of Early Cold-Regulated Proteins by Two-Dimensional Difference Gel Electrophoresis Reveals a Key Role for Phospholipase Dα1 in Mediating Cold Acclimation Signaling Pathway in Rice.

PubMed

Huo, Chenmin; Zhang, Baowen; Wang, Hui; Wang, Fawei; Liu, Meng; Gao, Yingjie; Zhang, Wenhua; Deng, Zhiping; Sun, Daye; Tang, Wenqiang

2016-04-01

To understand the early signaling steps that regulate cold responses in rice, two-dimensional difference gel electrophoresis (2-D DIGE)(1)was used to study early cold-regulated proteins in rice seedlings. Using mass spectrometry, 32 spots, which represent 26 unique proteins that showed an altered expression level within 5 min of cold treatment were identified. Among these proteins, Western blot analyses confirmed that the cellular phospholipase D α1 (OsPLDα1) protein level was increased as early as 1 min after cold treatment. Genetic studies showed that reducing the expression ofOsPLDα1makes rice plants more sensitive to chilling stress as well as cold acclimation increased freezing tolerance. Correspondingly, cold-regulated proteomic changes and the expression of the cold-responsive C repeat/dehydration-responsive element binding 1 (OsDREB1) family of transcription factors were inhibited in thepldα1mutant. We also found that the expression ofOsPLDα1is directly regulated by OsDREB1A. This transcriptional regulation ofOsPLDα1could provide positive feedback regulation of the cold signal transduction pathway in rice. OsPLDα1 hydrolyzes phosphatidylcholine to produce the signal molecule phosphatidic acid (PA). By lipid-overlay assay, we demonstrated that the rice cold signaling proteins, MAP kinase 6 (OsMPK6) and OsSIZ1, bind directly to PA. Taken together, our results suggest that OsPLDα1 plays a key role in transducing cold signaling in rice by producing PA and regulatingOsDREB1s' expression by OsMPK6, OsSIZ1, and possibly other PA-binding proteins. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Platinum Group Elements, 187OS/188OS and 87SR/86SR Isotope Systematics in Depleted Fluid-Modified Mariana Fore-Arc Peridotites

NASA Astrophysics Data System (ADS)

Harvey, J.; Savov, I. P.; Shirey, S. B.; Horan, M. F.; Mock, T. D.

2012-12-01

The serpentine mud volcanoes of the Izu-Bonin-Mariana (IBM) fore-arc, collected during Ocean Drilling Program Leg 195 [1], contain hard-rock clasts of serpentine sampled from close to the décollement, which separates the down-going Pacific slab from the overlying mantle wedge. These clasts preserve evidence for melt depletion (>25 % melt extraction in many instances) in a sub-arc environment, and extensive (40 - 100%) serpentinization due to subsequent fluid / peridotite interaction, e.g. [2]. Platinum-group element (PGE) abundances are not consistent with melt-depletion alone [3]. Fractionation between I-PGE (Os, Ir, Ru) has resulted in groups of IBM serpentinites with either a high chondrite-normalized Os/Ir ratio (OsN/IrN) or a low OsN/IrN ratio. Similarly, fractionation of P-PGE (Pt, Pd) is marked, and distinguishes the IBM serpentinites from worldwide abyssal peridotites. Interaction with high-pH fluids [4] may have partially oxidized mantle sulphide, the major primary host for PGE in these rocks, leading to partial breakdown to sulphate and the selective redistribution of certain PGE (Os, Ru, Pt), a feature normally associated with sub-aerial weathering [5], but which likely prevails in other oxidizing environments. In particular, the Re-Os systematics of the high (OsN/IrN) IBM serpentinites have been disturbed by the addition of Os. Unlike peridotite xenoliths associated with magmatic regions of subduction zones where subduction-related Os-addition is unequivocally radiogenic and derived from crustal material [6][7], where Os has been added to the IBM serpentinites it is unradiogenic and was most likely derived from within the oceanic mantle. IBM serpentinites therefore preserve osmium isotope ratios that are exclusively sub-chondritic (187Os/188Os ≤ 0.127), as previously reported [8]. These serpentinized peridotites were produced by at least a three-step process: melt depletion, serpentinization, and the mobilization of Os, Ru and Pt to produce low OsN/IrN "donor" and high OsN/IrN "recipient" serpentinites. The distinct chondrite normalized PGE patterns of the low OsN/IrN serpentinites are remarkably similar to those of back-arc basin basalts (BABB) from sites 291, 292, 444A, 450 drilled in the Philippine Sea Plate (PSP) during DSDP Legs 31, 58 and 59 [9]. [1] Fryer, et al. (1992) Proc. ODP Sci. Results 125, Fryer, P., Pearce, J. A., Stokking, L. B., et al., 373-385, Ocean Drilling Program, College Station TX, USA. [2] Savov et al. (2005) Geochem. Geophys. Geosyst. 6, Q04J15, doi:10.1029/2004GC000777 [3] Handler, & Bennett (1999) Geochim. Cosmochim. Acta 63, 3597-3618 [4] Mottl, M.J. (1992) Proc. ODP Sci. Results, 125, Fryer, P., Pearce, J. A., Stokking, L. B., et al., 373-385, Ocean Drilling Program, College Station TX, USA. [5] Lorand, et al. (2003) Geochim. Cosmochim. Acta 67, 4137-4151. [6] Brandon et al. (1999) Chem. Geol. 160, 387-407. [7] Widom et al. (2003) Chem. Geol. 196, 283- 306. [8] Parkinson et al. (1999) Science 281, 211-312 [9] Dale et al. (2008) Chem. Geol. 248, 213-238.

Sexual Health Promotion Programme: Participants' Perspectives on Capacity Building

ERIC Educational Resources Information Center

Keogh, Brian; Daly, Louise; Sharek, Danika; De Vries, Jan; McCann, Edward; Higgins, Agnes

2016-01-01

Objectives: The aim of this study was to evaluate a Health Service Executive (HSE) Foundation Programme in Sexual Health Promotion (FPSHP) with a specific emphasis on capacity building. Design: A mixed-method design using both quantitative and qualitative methods was used to collect the data. Setting: The FPSHP was delivered to staff working in…

Back to School: A Guide to Continuing Your Education after Prison

ERIC Educational Resources Information Center

Crayton, Anna; Lindahl, Nicole

2015-01-01

This guide is designed to help readers take the first steps towards continuing their education, whether that means learning English, working towards a High School Equivalency (HSE), learning an occupation, or building on college credits already earned. This guide walks readers through the process of setting educational goals and getting organized;…