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The continental crust of Iran is dominated by abundant calc-alkaline and alkaline plutonic and volcanic rocks and by rifted basins filled with mostly terrigenous sedimentary rocks that formed at a Late Ediacaran to Cambrian extensional convergent plate margin along the northern margin of Gondwana. Here we present new zircon U–Pb age, geochemical, and isotopic data from plutonic (granite-granodiorite) and metamorphic (gneiss) rocks in the Kariznou region of NE Iran to provide insights into the nature of the Cadomian convergent margin of Iran. Geochemical data indicate calc-alkaline signatures, characterized by strong depletions in Nb, Ta, P, and Ti and arc-like trace element patterns. New zircon U–Pb ages show that calc-alkaline granitoids and granitic gneiss formed at ~564 to 537 Ma and 538 Ma, respectively. Bulk rock Sr-Nd isotopic data of calc-alkaline rocks have εNd(t) = –5.42 to −5.53 and −6.93 to −7.43 for granite and gneiss, respectively. The gneisses show stronger interaction with and/or re-melting of older continental crust than do granitic rocks. We interpret Kariznou magmatic rocks as forming in association with strong extension accompanied by crustal assimilation. Extension initiated ~570 Ma with the deposition of Late Ediacaran sediments, and magmatism began at 545–535 Ma, generating calc-alkaline magmas. The tectonomagmatic evolution of the Kariznou region encapsulates the prolonged transition of Cadomian Iran from a strongly extensional convergent margin, possibly as a result of oblique oceanic subduction and slab roll-back of the subducting Proto-Tethys oceanic lithosphere, culminating in the formation of an Early Palaeozoic passive margin on the northern side of Gondwana. [ABSTRACT FROM AUTHOR]

Several Mesozoic ophiolites in Iran formed in response to Late Cretaceous subduction initiation. Here we review the geology, petrography, mineralogy and geochemistry of mantle rocks from the Nain, Neyriz, Khoy, Esfandagheh and Fannuj ophiolites. They are remnants of Neo-Tethys ocean lithosphere formed during subduction initiation and were emplaced onto the southern flank of Eurasia. Most show SSZ-type geochemical affinity. We summarize the composition of mantle sections from these five representatives, which comprise lherzolites and harzburgites with minor dunite lenses and sometimes chromitites. Spinels in lherzolite from all regions are characterized by low chromium number [Cr# = Cr/(Al + Cr)] of 0.09 to 0.56 and plot in the abyssal peridotite field, whereas spinel in harzburgite and dunite-chromitite have Cr# of 0.41 to 0.73 and 0.45 to 0.86, respectively, showing geochemical affinities with forearc peridotites and boninites, respectively. Lherzolites and harzburgites have low rare earth element (REE) contents and experienced around 15% and 25% partial melting, respectively. Ophiolitic peridotites from the Nain (inner Zagros ophiolitic belt), Khoy, and Neyriz (outer Zagros ophiolitic belt) complexes are depleted in light REE and show flat heavy REE patterns. By contrast, peridotites from the Fannuj (Makran ophiolitic zone) and Esfandagheh (outer Zagros ophiolitic belt) complexes are characterized by flatter and U-shaped REE patterns, respectively, similar to those of SSZ peridotites. Based on the compositions of olivine and spinel, we infer that chromitites and their dunite envelopes experienced wider variations in oxygen fugacity (fO2), equilibrium temperatures, and spinel Cr# values than those of the surrounding lherzolites and harzburgites, suggesting interaction between residual mantle harzburgites and H2O-rich and highly oxidized SSZ melts. Lherzolites from all regions and harzburgites of Nain, Neyriz and Fannuj are MOR-type peridotites that plot in the overlapping space of MOR peridotites and were generated in an extensional environment. These are forearc peridotites that were in equilibrium with tholeiitic melts generated during early proto-forearc or back-arc spreading during subduction initiation, whereas spinels of dunites and high-Cr chromitites were in equilibrium with boninitic melts. [ABSTRACT FROM AUTHOR]

Eocene igneous rocks along the Gangdese belt in southern Tibetan Plateau are important for understanding the India–Eurasia collision and Tibetan Plateau uplift. These magmatic rocks are widely considered to be related to roll-back or break-off of the Neotethyan slab during northward subduction. However, Eocene rhyolites in the northwestern Gangdese belt (SW Qiangtang margin) do not fit either the rollback or breakoff models. This paper investigates these Early Eocene lavas and compares them with contemporaneous igneous rocks along the Gangdese belt via detailed field observations, petrology, zircon geochronology, zircon Lu–Hf isotopes and whole-rock geochemistry. These felsic lavas form large outcrops in western Tibet and have two zircon U–Pb ages of 54.71 ± 0.14 Ma and 54.74 ± 0.27 Ma. They have high SiO2 and alkali contents, FeO*/MgO, and Ga/Al ratios as well as strongly negative Eu anomalies and slightly positive zircon εHf(t) values (+2.5 to +4.4). Both Ti-in-zircon and Zr saturation thermometers confirm high magmatic temperatures (~900°C). They are ferroan, A-type rhyolites. Furthermore, the distinctive low εHf(t) values imply that these rhyolites are likely partial melting products of the southwestern Qiangtang Terrane. The lithosphere in this region undergone long-term shortening and thickening since 80–95 Ma. Pre-thickened lithosphere may be a prerequisite for the Early Eocene delamination, and the simultaneous inducement is a far-field tectonic effect from the India–Eurasia collision. We suggest that: (1) India collided with Eurasia before 55 Ma and triggered delamination to form the Shiquanhe A-type rhyolites on the southwestern Qiangtang margin thereafter; and (2) tectonic stresses related to India–Eurasia collision during the Eocene were transmitted efficiently over large distances. [ABSTRACT FROM AUTHOR]

The M 6.5 earthquake that occurred in the Monte Cristo Range near Mina, Nevada on 15 May 2020 was exceptionally well-recorded with both seismic and geodetic instrumentation. The arid nature of the region also facilitated detailed ground mapping of the surface rupture. Here we integrate several independent data sets to illustrate the educational and research opportunities afforded by these rich data sets. We construct a series of models for slip at depth that are consistent with the satellite-derived geodetic data, the distribution of aftershocks, and the mapped surface rupture. We also show that the modelled depth of maximum slip is in good agreement with heat flow and laboratory data on quartz rheology defining the depth of the brittle-ductile transition. The Monte Cristo Range earthquake also suggests new approaches to seismic hazard assessment may be required for earthquakes in rapidly evolving tectonic regions such as the Walker Lane and Eastern California shear zone. [ABSTRACT FROM AUTHOR]

Deposits of semi-gemstones tourmaline, beryl, and garnet associated with Jurassic granites are found in the northern Sanandaj–Sirjan Zone (SaSZ) of western Iran, defining a belt that can be traced for about 400 km. Granitic magmas strongly interacted with or were derived from melts of continental crust and/or sediments. Based on morphologies, size, mineral assemblage, and contact relationships with host granite and associated metamorphic aureoles, these deposits are categorized into six types: (1) garnet in skarns, (2) tourmaline, beryl, and garnet in pegmatite and aplitic dikes, (3) disseminations and patches of tourmaline in leucogranites, (4) quartz-tourmaline veins in granite, (5) tourmaline and garnet in metamorphic aureoles, and (6) tourmaline orbicules in aplite. Tourmalines are mostly schorl and dravite, and garnets are mostly almandine, spessartine, and grossular. Tourmaline, beryl, and garnet from pegmatites in the contact aureole of Jurassic granites reflect segregations of Be, B, Mn, and Al bearing melts from the Jurassic peraluminous granites. Quartz-tourmaline veins and hydrothermal garnets in skarns reflect fluids exsolved from the surrounding metasediment and pegmatite melt. In contrast, tourmaline patches and orbicules developed from boron-rich aqueous fluids exsolved from cooling granitic magma. Distribution of semi-gemstones in the SaSZ shows that these are mostly related to pegmatites associated with Jurassic granitic intrusions. Mineral equilibrium considerations indicate that SaSZ semi-gemstones crystallized at P = 3.5–7.5 kbar (11.5–25 km deep) and temperatures of 550–650°C. SaSZ pegmatites fall in the muscovite (MS) and MS-rare element classes. They are Lithium Cesium Tantalum (LCT)-type pegmatites. Fluids responsible for gem mineralization were exsolved from cooling granite bodies and released by metamorphosed sediments. Further studies are needed to better understand the northern Sanandaj–Sirjan tourmaline–garnet–beryl semi-gemstone Province. [ABSTRACT FROM AUTHOR]

Cadomian calc-alkaline I-type and within-plate A-type igneous rocks are widespread in the crust of Iran where they are ascribed to a convergent margin associated with the southward subduction of Prototethyan oceanic lithosphere beneath N Gondwana. These rocks are found as unmetamorphosed magmatic rocks and their metamorphic equivalents (mafic to felsic gneisses) could have been generated in both Cadomian arcs and associated rear-arcs. Nearly all these exposures also contain metamorphosed metasediments, whereas Cadomian igneous rocks of central Iran are associated with thick sequences of unmetamorphosed terrigenous rocks. In the Zagros Fold-Thrust belt of S Iran, salt diapirs contain abundant xenoliths of Cadomian igneous and sedimentary rocks in association with evaporites, dolomites, carbonates, and banded iron-salt deposits. This paper presents new zircon U-Pb and geochemical-isotopic data from igneous clasts in the Chah-Banu salt diapir in SE Zagros. Petrographic and geochemical data indicate two different types of rock clasts; calc-alkaline, I-type dacites-rhyolites, and arc-related to E-MORB-OIB-like gabbros, basalts, and dolerites. New zircon U-Pb ages show that dacites formed at 538.2 ± 2.2 Ma, whereas gabbros show ages of 539.0 ± 1.8 Ma. Zircons from dacites have negative εHf(t) values of – 1.1 to – 8.3. In contrast, zircons from gabbros have higher εHf(t) values of +4.5 to +8.5, indicating crystallization from mantle-derived juvenile magmas. Bulk rock Nd-Sr isotopic data (e.g. ɛNd(t) = +0.3 to +4.0 and 87Sr/86Sr(i) = 0.7059 to 0.70848) for gabbros, dolerites, and basalts confirm that these rocks originated from a mantle source similar to enriched parts of the subcontinental lithospheric mantle, whereas dacites and rhyolites (with εNd(t) = −3.4 to −4.1 and 87Sr/86Sr(i) = 0.70806 to 0.70907) show strong interaction with, and/or re-melting of older continental crust. We suggest that the bimodal calc-alkaline and E-MORB-OIB-like magmatic rocks in salt diapirs as well as associated evaporites and sedimentary rocks formed in a retro-arc rifted basin behind the Cadomian magmatic arc. [ABSTRACT FROM AUTHOR]

Garnets show wide ranges of chemical compositions and are key minerals for reconstructing the thermodynamic evolution of metamorphic terranes. The properties of garnets – including Mohs hardness ~7, lack of cleavage, vitreous luster and multiple colors – also makes them useful as semi-gemstones. Garnets are widespread accessory minerals in igneous and metamorphic rocks of western and southern Iran and are especially abundant in skarns and regional metamorphic rocks. 45 garnet deposits of western and southern Iran show six associations: (1) skarn (35 locations); (2) peraluminous granitoid and rhyolite (4 locations); (3) alkaline granite (1 location); (4) metamorphic rocks (3 locations); and (5) ophiolites (2 locations). Distinct garnet compositions are found in each association: mostly grossular-andradite in skarn, Ti-andradite in alkaline granite, almandine in peraluminous granite and volcanic rocks, almandine-grossular in metamorphic rocks and andradite- uvarovite associated with ophiolites. Western and southern Iran garnets are mostly related to skarns around Cenozoic granitoid intrusions. Ti-rich garnet formed at the expense of clinopyroxenites in alkaline igneous complexes due to alkaline metasomatism. These associations are useful for understanding garnet semi-gemstone deposits in western and southern Iran. [ABSTRACT FROM AUTHOR]

Late Eocene – Oligocene volcanic rocks in the eastern Saveh region of the Urumieh-Dokhtar magmatic arc (UDMA) are representative of Paleogene magmatic activity in Iran. They show a wide range of silica-undersaturated to silica-oversaturated compositions, from basalt-trachy basalt and tephri-phonolite to trachyte-latite. Whole rock chemical compositions define a continuous assemblage of mafic and felsic rocks in terms of SiO2 (46.3 to 71.1 wt.%), Al2O3 (12.5–19.2 wt.%), K2O (2.06–12.23 wt.%) and TiO2 (0.41–1.75 wt.%) contents, Mg number (6.8–51) and K2O/Na2O ratios (0.53–30.2). Abundances of rare earth elements in the tephri-phonolite group are much higher than in the trachyte-latite and basalt-trachy basalt groups. Elevated contents of large ion lithophile elements such as Ba (191–7311 ppm) and Pb (6.49–118 ppm) as well as depletions in high field strength elements such as Nb (2.43–40.6 ppm), Ta (0.15–2.24 ppm), Zr (40.8–258 ppm) and TiO2 (0.40–1.77 wt.%) characterize these rocks. Initial ratios of 87Sr/86Sr from 0.7046 to 0.7074 and ɛNd(t) from +0.9 to +3.3 show that these were derived from parental magma extracted from partial melting of metasomatized mantle, namely amphibole- and/or phlogopite-bearing peridotite. Fractionation of feldspar, clinopyroxene, amphibole and phlogopite, and minor contamination with upper crust was responsible for the large variation of the rock types observed. We explain contemporaneous late Eocene – Oligocene calc-alkaline and high-K magmatic activity in the UDMA as due to the partial melting of both hot metasomatized asthenospheric and subcontinental lithospheric mantle in an extensional tectonic regime. This extensional regime probably developed due to the rollback of the subducted Neo-Tethys oceanic plate. [ABSTRACT FROM AUTHOR]

My aim in this paper is to consider whether, by thinking of our ethical relation to one another in terms of vulnerability, we can better resolve the problem of overdemandingness – namely, that certain moral views and theories seem to require more of us than is reasonably acceptable. I will suggest that there is a way in which focusing on vulnerability, rather than merely needs or wants, can help address the issue of overdemandingness, largely because of the relational nature of vulnerability, and how this connects to our power over others. In arguing this case, I will draw on the work of the Danish philosopher and theologian K. E. Løgstrup. I explore how Løgstrup shows how this might work in relation to a central form of vulnerability which he emphasises, namely trust. I then consider an objection, namely that trust is a rather special case of vulnerability, which is less open to the problem of overdemandingness only because it has particular features which do not apply to vulnerability more generally. I then respond to this objection by considering if lessons learnt from the case of trust could still nonetheless be extended more widely to other forms of vulnerability. Doing so, I will suggest, might show how thinking in terms of vulnerability as Løgstrup conceives it can help us with the problem of overdemandingness [ABSTRACT FROM AUTHOR]

We address the growing controversy about the tectonic setting in which Jurassic magmatism of Iran occurred: arc or continental rift. In the Ghorveh area of the northern Sanandaj Sirjan zone (SaSZ), the Ghalayan metabasites are interlayered with marble and schist and locally cut by acidic dikes. Zircon U-Pb dating of the metabasitic rocks shows that these crystallized at ca. 145–144 Ma ago in the Late Jurassic (Tithonian). This complex was metamorphosed in the lower greenschist facies, however, some protolithic structures such as pillow lava and primary minerals are preserved. The metabasites are tholeiites with low SiO2 (45.6–50.5 wt.%), moderate Al2O3 (11.3–17.0 wt.%), and high TiO2 (0.7–2.9 wt.%) and Fe2O3 (9.4–14.1 wt.%). The Ghalayan metabasites are enriched in Light rare earth elements (LREEs) without significant Nb, Ta, Pb, Sr and Ba anomalies, similar to modern continental intra-plate tholeiitic basalts such as Afar and East African rifts. The Ghalaylan metabasites show wide ranges for 87Sr/86Sr(i) (0.7039–0.7077) and positive εNd(t) values (+0.1 to +4.6). These isotopic compositions are similar to those expected for slightly depleted subcontinental lithospheric mantle sources. Independently built discrimination diagrams indicate an intra-continental rifting regime for the source of Jurassic metabasites in the northern SaSZ. Geochemical and tectonic evidence suggests that rifting or a mantle plume was responsible for volcanic activity in the Upper Jurassic SaSZ. Considering the variation of ages of basaltic volcanism along the SaSZ, we suggest that Ghalayan basaltic magmatism reflected a submarine volcano that formed as part of the late stage continental rift, similar to Afar in the East African Rift system. Our results indicate that an extensional tectonic regime dominated SaSZ tectonics in the Middle to Late Jurassic. [ABSTRACT FROM AUTHOR]

Collision of Gondwana and Laurentia in the late Palaeozoic created new topography, drainages, and foreland basin systems that controlled sediment dispersal patterns on southern Laurentia. We utilize sedimentological and detrital zircon data from early Permian (Cisuralian/Leonardian) submarine-fan deposits in the Midland Basin of west Texas to reconstruct sediment dispersal pathways and palaeogeography. New sedimentological data and wire-line log correlation suggest a portion of the early Permian deposits have a southern entry point. A total of 3259 detrital zircon U-Pb and 357 εHf data from 12 samples show prominent groups of zircon grains derived from the Appalachian (500–270 Ma) and Grenville (1250–950 Ma) provinces in eastern Laurentia and the peri-Gondwana terranes (800–500 Ma) incorporated in the Alleghanian-Ouachita-Marathon orogen. Other common zircon groups of Mesoproterozoic-Archaean age are also present in the samples. The detrital zircon data suggest throughout the early Permian, Appalachia and Gondwana detritus was delivered by a longitudinal river system that flowed along the Appalachian-Ouachita-Marathon foreland into the Midland Basin. Tributary channels draining the uplifted Ouachita-Marathon hinterland brought Gondwana detritus into the longitudinal river with headwaters in the Appalachians or farther northeast. This drainage extended downstream westward and delivered sediments into the Permian Basin near the west terminus of the Laurentia-Gondwana suture. Estimated rates of deposition and proportions of zircons from more local (Grenville) versus more distal (Pan-African) sources indicate that river strength decreased throughout early Permian time. Primary sediment delivery pathway was augmented by minor input from the Ancestral Rocky Mountains and wind deflation of fluvial sediments north and east of the basin. Slope failure associated with early Permian deposition in the southeastern margin of the Midland Basin triggered gravity flows leading to submarine fan deposition. [ABSTRACT FROM AUTHOR]

The Baneh plutonic complex is situated in the Zagros suture zone of northwest Iran between the Arabian and Eurasian plates. This complex is divided into granite and appinite groups. Zircon U- Pb dating shows that granites crystallized 41-38 million years ago but appinites experience more protracted magmatic evolution, from at 52 to 38 Ma. Whole-rock chemical compositions show significant major and trace element variations between the two lithologies. Granitic rocks are more evolved, with high contents of SiO2 (62.4-77.0 wt%), low contents of TiO2 (0.25 wt%), MgO (0.05-1.57 wt%), and Fe2O3 (0.40-4.06 wt%) and high contents of Na2O + K2O (≈10 wt%). In contrast, appinites have low contents of SiO2 (51.0-57.0 wt%) and K2O (<2.1 wt%) and high Fe2O3 (6.4-9.35 wt%), MgO (2.0-9.9 wt%), and Mg number (Mg# = 35-76). The concentration of rare earth elements in the appinites is higher than in granitic rocks, making it difficult to form granites solely by fractionation of appinite magma. (87Sr/86Sr)i and εNd(40 Ma) in both groups are similar, from 0.7045 to 0.7061 and -1.2 to +2.6, except for a primitive gabbroic dike with εNd(40 Ma) = +9.9. Appinites show mainly typical I-type characteristics, but granites have some S-type characteristics. The sigmoidal shape of the Baneh pluton and its emplacement into deformed Cretaceous shales and limestone showing kink bands, asymmetric and recumbent folds in a broad contact zone, with pervasive ductile to brittle structures in both host rocks and intrusion, indicate that magma emplacement was controlled by a transpressional tectonic regime, perhaps developed during early stages in the collision of Arabia and Eurasian plates. [ABSTRACT FROM AUTHOR]

Objective: Identify biomarkers in peripheral blood that relate to chronic post-concussive and behavioural symptoms following traumatic brain injuries (TBIs) to ultimately improve clinical management. Research design: We compared military personnel with mild TBIs (mTBIs) (n = 42) to those without TBIs (n = 22) in concentrations of tau, amyloid-beta (Aβ42) and cytokines (tumour necrosis factor alpha (TNFα, interleukin (IL)-6 and -10) in neuronal-derived exosomes from the peripheral blood. We utilized nanosight technology coupled with ultra-sensitivity immunoassay methods. We also examined the impact of post-concussive and behavioural symptoms including depression and post-traumatic stress disorder (PTSD) on these neuronal-derived markers. Results: We report that concentrations of exosomal tau (F1, 62 = 10.50), Aβ42 (F1, 61 = 5.32) and IL-10 (F1, 59 = 4.32) were elevated in the mTBI group compared to the controls. Within the mTBI group, regression models show that post-concussive symptoms were most related to exosomal tau elevations, whereas exosomal IL-10 levels were related to PTSD symptoms. Conclusions: These findings suggest that chronic post-concussive symptoms following an mTBI relate to altered exosomal activity, and that greater tau pathology may underlie chronic post-concussive symptoms that develop following mTBIs. It also suggests that central inflammatory activity contributes to PTSD symptoms following an mTBI, providing necessary insights into the role of inflammation in chronic PTSD symptoms. [ABSTRACT FROM AUTHOR]

The Wadi Bidah Mineral District of Saudi Arabia contains more than 16 small outcropping stratabound volcanogenic Cu–Zn–(Pb) ± Au-bearing massive sulphide deposits and associated zones of hydrothermal alteration. Here, we use major and trace element analyses of massive sulphides, gossans, and hydrothermally altered and least altered metamorphosed host rock (schist) from two of the deposits (Shaib al Tair and Rabathan) to interpret the geochemical and petrological evolution of the host rocks and gossanization of the mineralization. Tectonic interpretations utilize high-field-strength elements, including the rare earth elements (REE), because they are relatively immobile during hydrothermal alteration, low-grade metamorphism, and supergene weathering and therefore are useful in constraining the source, composition, and physicochemical parameters of the primary igneous rocks, the mineralizing hydrothermal fluid and subsequent supergene weathering processes. Positive Eu anomalies in some of the massive sulphide samples are consistent with a high temperature (>250°C) hydrothermal origin, consistent with the Cu contents (up to 2 wt.%) of the massive sulphides. The REE profiles of the gossans are topologically similar to nearby hydrothermally altered felsic schists (light REE (LREE)-enriched to concave-up REE profiles, with or without positive Eu anomalies) suggesting that the REE experienced little fractionation during metamorphism or supergene weathering. Hydrothermally altered rocks (now schists) close to the massive sulphide deposits have high base metals and Ba contents and have concave-up REE patterns, in contrast to the least altered host rocks, consistent with greater mobility of the middle REE compared to the light and heavy REE during hydrothermal alteration. The gossans are interpreted to represent relict massive sulphides that have undergone supergene weathering; ‘chert’ beds within these massive sulphide deposits may be leached wall-rock gossans that experienced silicification and Pb–Ba–Fe enrichment from acidic groundwaters generated during gossan formation. [ABSTRACT FROM AUTHOR]

Objective: Former National Football League (NFL) players’ working knowledge of concussion has not yet been evaluated, despite this population being a major clinical research target due to the association between repetitive head impacts (RHI) and long-term clinical impairments. This study examined former NFL players’ understanding of the current concussion definition, and the association between number of concussions with clinical function. Methods: 95 former NFL players (mean age = 55.29; mean NFL year = 8.10) self-reported number of concussions before being provided with a concussion definition and after being read a modern definition of concussion. Subjects reported number of concussions with loss of consciousness (LOC). Principal Component Analysis of a battery of tests generated behaviour/mood, psychomotor speed/executive function, and verbal and visual memory factor scores. Results: Post-definition number of concussions (median = 50) was five times the pre-definition (median = 10;p< 0.001). Greater pre- (p= 0.019) and post-definition concussions (p= 0.036) correlated with worse behaviour/mood scores, after controlling for years of football played, with specific effects for depressive symptoms and impulsivity. LOC did not account for variance beyond number of concussions. Conclusions: Practitioners and clinical researchers should provide a definition of concussion in the assessment of concussion history in former football players to facilitate accuracy and standardization. [ABSTRACT FROM PUBLISHER]

Ultramafic portions of ophiolitic fragments in the Arabian–Nubian Shield (ANS) show pervasive carbonate alteration forming various degrees of carbonated serpentinites and listvenitic rocks. Notwithstanding the extent of the alteration, little is known about the processes that caused it, the source of the CO2or the conditions of alteration. This study investigates the mineralogy, stable (O, C) and radiogenic (Sr) isotope composition, and geochemistry of suites of variably carbonate altered ultramafics from the Meatiq area of the Central Eastern Desert (CED) of Egypt. The samples investigated include least-altered lizardite (Lz) serpentinites, antigorite (Atg) serpentinites and listvenitic rocks with associated carbonate and quartz veins. The C, O and Sr isotopes of the vein samples cluster between −8.1‰ and −6.8‰ for δ13C, +6.4‰ and +10.5‰ for δ18O, and87Sr/86Sr of 0.7028–0.70344, and plot within the depleted mantle compositional field. The serpentinites isotopic compositions plot on a mixing trend between the depleted-mantle and sedimentary carbonate fields. The carbonate veins contain abundant carbonic (CO2±CH4±N2) and aqueous-carbonic (H2O-NaCl-CO2±CH4±N2) low salinity fluid, with trapping conditions of 270–300°C and 0.7–1.1 kbar. The serpentinites are enriched in Au, As, S and other fluid-mobile elements relative to primitive and depleted mantle. The extensively carbonated Atg-serpentinites contain significantly lower concentrations of these elements than the Lz-serpentinites suggesting that they were depleted during carbonate alteration. Fluid inclusion and stable isotope compositions of Au deposits in the CED are similar to those from the carbonate veins investigated in the study and we suggest that carbonation of ANS ophiolitic rocks due to influx of mantle-derived CO2-bearing fluids caused break down of Au-bearing minerals such as pentlandite, releasing Au and S to the hydrothermal fluids that later formed the Au-deposits. This is the first time that gold has been observed to be remobilized from rocks during the lizardite–antigorite transition. [ABSTRACT FROM PUBLISHER]

The article reports on the instances showing the failure of scientists and engineers to manage future technological policy towards a socially constructive plan. Their failure has made a devastating effect on the decision-making process of the government. The supersonic transport and the anti-ballistic missile debates of 1969-70 has demonstrated such difficulty on the part of scientists to make assumptions and technical advice that could be useful to the government and the public. Thus, the federal government has established an independent research organization that will report to the Congress on the technical aspects of legislative issues.

The Biarjmand granitoids and granitic gneisses in northeast Iran are part of the Torud–Biarjmand metamorphic complex, where previous zircon U–Pb geochronology show ages of ca. 554–530 Ma for orthogneissic rocks. Our new U–Pb zircon ages confirm a Cadomian age and show that the granitic gneiss is ~30 million years older (561.3 ± 4.7 Ma) than intruding granitoids (522.3 ± 4.2 Ma; 537.7 ± 4.7 Ma). Cadomian magmatism in Iran was part of an approximately 100-million-year-long episode of subduction-related arc and back-arc magmatism, which dominated the whole northern Gondwana margin, from Iberia to Turkey and Iran. Major REE and trace element data show that these granitoids have calc-alkaline signatures. Their zircon O (δ18O = 6.2–8.9‰) and Hf (–7.9 to +5.5; one point with εHf ~ –17.4) as well as bulk rock Nd isotopes (εNd(t) = –3 to –6.2) show that these magmas were generated via mixing of juvenile magmas with an older crust and/or melting of middle continental crust. Whole-rock Nd and zircon Hf model ages (1.3–1.6 Ga) suggest that this older continental crust was likely to have been Mesoproterozoic or even older. Our results, including variable zircon εHf(t) values, inheritance of old zircons and lack of evidence for juvenile Cadomian igneous rocks anywhere in Iran, suggest that the geotectonic setting during late Ediacaran and early Cambrian time was a continental magmatic arc rather than back-arc for the evolution of northeast Iran Cadomian igneous rocks. [ABSTRACT FROM PUBLISHER]

Whether or not magmatic arcs evolve compositionally with time and the processes responsible remain controversial. Resolution of this question requires the reconstruction of arc geochemical evolution at the level of a discrete arc system. Here, we address this problem using the well-studied Central American Volcanic Arc System (CAVAS) as an example. Geochemical and isotopic data were compiled for 1031 samples of lavas and intrusive rocks from the ~1100 km-long segment of oceanic CAVAS (Panama, Costa Rica, Nicaragua) built on thickened oceanic crust over its 75 million year lifespan. We used available age constraints to subdivide this data set into six magmatic phases: 75–39 Ma (Phase I or PI); 35–16 Ma (PII); 16–6 Ma (PIII); 6–3 Ma (PIV); 5.9–0.01 Ma (PVa arc alkaline and PVb adakitic); and 2.6–0 Ma (PVI, Quaternary to modern magmatism, predominantly ≪ 1 Ma). To correct for magmatic fractionation, selected major and trace element abundances were linearly regressed to 55 wt.% SiO2. The most striking observation is the overall evolution of the CAVAS to more incompatible element enriched and ultimately continental-like compositions with time, although magmatic evolution took on a more regional character in the youngest rocks, with magmatic rocks of Nicaragua becoming increasingly distinguishable from those of Costa Rica and Panama with time. Models entailing progressive arc magmatic enrichment are generally supported by the CAVAS record. Progressive enrichment of the oceanic CAVAS with time reflects changes in mantle wedge composition and decreased melting due to arc crust thickening, which was kick-started by the involvement of enriched plume mantle in the formation of the CAVAS. Progressive crustal thickening and associated changes in the sub-arc thermal regime resulted in decreasing degrees of partial melting over time, which allowed for progressive enrichment of the CAVAS and ultimately the production of continental-like crust in Panama and Costa Rica by ~16–10 Ma. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the author talks about the articles published in the issue including "Hegel as a Pragmatist" by Dina Emundts, "Hegel, Habits, and Pragmatism" by Steven Levine, and "Inference by Analogy and the Progress of Knowledge" by Preston Stovall.

Objective: Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative disease associated with repetitive brain trauma (RBT). Initially described in boxers, CTE has now been found in other contact sport athletes with a history of RBT. In recent years, there has been tremendous media attention regarding CTE, primarily because of the deaths of high profile American football players who were found to have CTE upon neuropathological examination. However, the study of CTE remains in its infancy. This review focuses on research from the Centre for the Study of Traumatic Encephalopathy (CSTE) at Boston University. Methods: This study reviews the formation of the CSTE, major CSTE publications and current ongoing research projects at the CSTE. Results: The neuropathology of CTE has been well-described. Current research focuses on: methods of diagnosing the disease during life (including the development of biomarkers), examination of CTE risk factors (including genetic susceptibility and head impact exposure variables); description of the clinical presentation of CTE; development of research diagnostic criteria for Traumatic Encephalopathy Syndrome; and assessment of mechanism and pathogenesis. Conclusions: Current research at the BU CSTE is aimed at increasing understanding of the long-term consequences of repetitive head impacts and attempting to begin to answer several of the unanswered questions regarding CTE. [ABSTRACT FROM AUTHOR]

The Neyriz ophiolite along the northeast flank of the Zagros fold-thrust belt in southern Iran is an excellent example of a Late Cretaceous supra-subduction zone (SSZ)-related ophiolite on the north side of the Neotethys. The ophiolite comprises a mantle sequence including lherzolite, harzburgite, diabasic dikes, and cumulate to mylonitic gabbro lenses, and a crustal sequence comprising a sheeted dike complex and pillow lavas associated with pelagic limestone and radiolarite. Mantle harzburgites contain less CaO and Al2O3, are depleted in rare earth elements, and contain spinels that are more Cr-rich than lherzolites. Mineral compositions of peridotites are similar to those of both abyssal and SSZ- peridotites. Neyriz gabbroic rocks show boninitic (SSZ-related) affinities, while crustal rocks are similar to early arc tholeiites. Mineral compositions of gabbroic rocks resemble those of SSZ-related cumulates such as high forsterite olivine, anorthite-rich plagioclase, and high-Mg# clinopyroxene. Initial εNd(t) values range from +7.9 to +9.3 for the Neyriz magmatic rocks. Samples with radiogenic Nd overlap with least radiogenic mid-ocean ridge basalts and with Semail and other Late Cretaceous Tethyan ophiolitic rocks. Initial87Sr/86Sr ranges from 0.7033 to 0.7044, suggesting modification due to seafloor alteration. Most Neyriz magmatic rocks are characterized by less radiogenic207Pb/204Pb (near the northern hemisphere reference line), suggesting less involvement of sediments in their mantle source. Our results for Neyriz ophiolite and the similarity to other Iranian Zagros ophiolites support a subduction initiation setting for its generation. [ABSTRACT FROM AUTHOR]

The depositional age of the Wadi Zaghra metasediments (Zaghra Formation) of the Sa’al-Zaghra metamorphic complex (Sinai) in the Arabian–Nubian Shield (ANS) has been constrained by LA-ICP-MS dating of zircons from (1) metaconglomerate granitoid clasts, (2) the metaconglomerate matrix, (3) biotite-schist, and (4) diorites and granites intruding the metasediments. Three granitoid boulders from a metadiamictite of the Zaghra Formation give crystallization ages of 651 ± 3, 647 ± 3, and 640 ± 4 Ma respectively. Detrital zircon age populations from laminated siltsones and conglomerate matrix vary somewhat with stratigraphic position, a variation best explained by changes in depositional environment and source area with time. Three distinct zircon age populations are identified in the matrix; at ca. 1000, 750, and 630 Ma, with less pronounced peaks at ~780 and ~800 Ma. The youngest detrital zircons indicate deposition after 630–625 Ma. The emplacement age of the post-depositional intrusives is enigmatic due to a large population of xenocrystic zircons, but is interpreted to be as old as ca. 615 Ma. This implies deposition and deformation of the Zaghra Formation in the time interval 625–615 Ma, thus older than the inferred depositional age of the Hammamat deposits in the Eastern Desert of Egypt, which is commonly correlated. The inferred depositional age is similar to the deposits in nearby Rutig Basin, where conglomerates were deposited in two pulses; at ca. 620–610 and 600–590 Ma. The appearance of late Mesoproterozoic (ca. 1.1 to –1.0 Ga) detrital zircons in the fine-grained laminated matrix facies of the Zaghra Formation demonstrates that ~1.0 Ga basement rocks (Sa’al terrane?) were exposed when Zaghra basin sediments were being deposited. [ABSTRACT FROM AUTHOR]

In this paper, I respond to three commentators on my book Understanding Moral Obligation: Kant, Hegel Kierkegaard. Anne Margaret Baxley focuses on my treatment of Kant, Dean Moyar on my treatment of Hegel, and William Bristow on my treatment of Kierkegaard. In this reply, I try to show how the critical points that they raise can be addressed. [ABSTRACT FROM PUBLISHER]

Neuropsychological tests are useful for diagnosing Alzheimer's disease (AD), yet for many tests, diagnostic accuracy statistics are unavailable. We present diagnostic accuracy statistics for seven variables from the Neuropsychological Assessment Battery (NAB) that were administered to a large sample of elderly adults (n = 276) participating in a longitudinal research study at a national AD Center. Tests included Driving Scenes, Bill Payment, Daily Living Memory, Screening Visual Discrimination, Screening Design Construction, and Judgment. Clinical diagnosis was made independent of these tests, and for the current study, participants were categorized as AD (n = 65) or non-AD (n = 211). Receiver operating characteristics curve analysis was used to determine each test's sensitivity and specificity at multiple cut points, which were subsequently used to calculate positive and negative predictive values at a variety of base rates. Of the tests analyzed, the Daily Living Memory test provided the greatest accuracy in the identification of AD and the two Screening measures required a significant tradeoff between sensitivity and specificity. Overall, the seven NAB subtests included in the current study are capable of excellent diagnostic accuracy, but appropriate understanding of the context in which the tests are used is crucial for minimizing errors. [ABSTRACT FROM PUBLISHER]

This paper considers whether Hegel's master/slave dialectic in the Phenomenology of Spirit should be considered as a refutation of solipsism. It focuses on a recent and detailed attempt to argue for this sort of reading that has been proposed by Frederick Beiser – but it argues that this reading is unconvincing, both in the historical motivations given for it in the work of Jacobi and Fichte, and as an interpretation of the text itself. An alternative reading of the dialectic is proposed, where it is argued that the central problem Hegel is concerned with is not solipsism, but the sociality of freedom. [ABSTRACT FROM PUBLISHER]

Deciding when an individual with dementia must reduce or stop driving can be a stressful issue for family caregivers. The purpose of this study was to develop a group intervention to assist these caregivers with driving issues and to provide a preliminary evaluation of the comparative effectiveness of this At the Crossroads intervention. Participants were randomized to one of three arms: (1) active intervention (four 2-hour manualized educational/support group meetings; n = 31); (2) written materials only (participants received written materials after a pretest; n = 23); and (3) control (participants received written materials after a posttest; n = 12). Participants were administered a battery of self-report and interview-based questionnaires at baseline and again 2 months later. At follow-up, the active intervention group scored significantly better than both other groups on key outcome variables, including self-efficacy, communication, and preparedness. The At the Crossroads caregiver intervention appears to effectively provide education and support needed for caregivers to address driving-related issues with their loved ones. [ABSTRACT FROM AUTHOR]

Objective: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare severe blistering skin diseases, which are mainly caused by drugs. The two idiosyncratic conditions are distinguished on the basis of the degree of blistering, possibly representing diseases at different ends of the same spectrum. A genetic predisposition has been postulated. Method: We have retrospectively identified a heterogeneous group of patients with SJS and TEN (n = 73 cases, 141 matched controls) induced by a number of marketed drugs and evaluated effector candidate genetic predisposition. We have used a multivariate genetic analysis method for the first time to handle the heterogeneity of clinical presentation, drug etiology, ethnicity and gender in these adverse events. Results: Our results show that predisposition varied according to ethnicity. There was a correlation for SJS with HLA-B*44, DRB1*07 and with the MHC ancestral 57.1 haplotype (and its constituents) in subjects who self-reported as Caucasians, which did not differ with gender. The HLA-DRB and -DRQ genetic predisposition to SJS seemed to be distinct from that of TEN, but further work is needed for both conditions to identify the causal variants. No conclusion concerning correlations with different drugs could be made because of small numbers in each drug group. Conclusion: This study stresses the importance of accurate clinical phenotyping, exemplifies a novel analysis method to dissect complicated samples and calls for collaborative prospective studies. [ABSTRACT FROM AUTHOR]

This paper focuses on one of C. S. Peirce's criticisms of G. W. F. Hegel: namely, that Hegel neglected to give sufficient weight to what Peirce calls "Secondness", in a way that put his philosophical system out of touch with reality. The nature of this criticism is explored, together with its relevant philosophical background. It is argued that while the issues Peirce raises go deep, in some respects Hegel's position is closer to his own than he may have realised, whilst in others that criticism can be resisted by the Hegelian. [ABSTRACT FROM AUTHOR]

To assess perceptions of the neuropsychological evaluation, 349 patients and 218 significant others presenting to an academic medical center neuropsychology service were surveyed over a two year period. Thirty-seven percent of the patient surveys (n = 129) and 37% of the significant other surveys (n = 80) were returned. Overall, both patients and significant others reported being satisfied with the interview, testing, and feedback sessions. Responders were generally receptive to the recommendations made, but were more inclined to have followed recommendations regarding patient safety (63.6%) than coping or support (31.8%). Some barriers to compliance with recommendations were identified. [ABSTRACT FROM AUTHOR]

The article discusses the case of the concrete universal, Hegel, and British idealism. The author reflects on how British idealists interpret and approach the thought of concrete universal philosophically. He argues that the work of idealists relate to Hegel's position, and opines that British idealists and Hegel may have the same approach and interest regarding thought involving abstraction from reality and their metaphysical and epistemological implications.

With NSF funding, we have developed, taught, and evaluated a new lower-division science course for non-science majors, entitled ‘Geology, Resources, and Environment of Latin America’ (GRELA). GRELA is intended to attract Hispanic undergraduates to science and to increase awareness among non-Hispanic students about challenges facing our neighbors to the south. GRELA is an interdisciplinary exploration of how the physical and biological environments of Mexico, Central America, and South America have influenced the people who live there. The course consists of 22 lectures in four modules (Background; Minerals; Energy and Natural Hazards, and Water and the Environment). Presentation of ESS topics dominates the last part of the class and includes lectures on El Niño, glaciers, the Amazon, rain forests, and coral reefs; a final set of lectures focuses on challenges facing the US and Mexico over shared water resources. Grades are based on two mid-term exams, a final exam and a report developed in partnership with correspondents in Latin American universities. Evaluations indicate this course positively impacts student interest in science, although some of the favorable comments may result from small class size. We encourage adaptation of our course materials at other community colleges and universities and will share these with other instructors on request. [ABSTRACT FROM AUTHOR]

Examines the use of inpatient neuropsychological evaluation by treating physicians in an acute medical hospital for patient care and discharge disposition. Results showing that majority of hospital discharge summaries included information regarding the neuropsychological evaluation by treating physicians in an acute medical hospital for patient care and discharge disposition; Consistency of actual placement outcomes with the neuropsychological evaluation placement recommendations for most of the time.

Clinical neuropsychologists often save as consultants to physicians. However, little is known about physicians' perceptions of the neuropsychological evaluation. Therefore, the present study examined the opinions of physicians who referred patients for neuropsychological evaluation. Surveys were mailed with the neuropsychological reports to 119 physicians who referred patients to an outpatient hospital-based neuropsychology practice over a 2-year period. Results showed that physicians requesting neuropsychological evaluations most commonly sought assistance with establishing and confirming and diagnosis, and they reported a high level of satisfaction with the evaluation, including strong agreement with diagnosis and recommendations. These findings did not differ based on physician specialty or patient diagnosis. [ABSTRACT FROM AUTHOR]

This paper is a discussion of Mark Bevir''s The Logic of the History of Ideas (Cambridge University Press, Cambridge, 1999). It focuses on three topics central to Bevir''s book: his weak intentionalism; his anthropological epistemology; and his priority claim regarding sincere, conscious, and rational beliefs. It is argued that Bevir''s position on these issues is problematic in certain important respects, and that some of his related critical claims against Pocock, Skinner and others are misconceived. [Copyright &y& Elsevier]

The Boston Qualitative Scoring System (BQSS) for the Rey-Osterrieth Complex Figure (ROCF) includes five scores (Planning, Fragmentation, Neatness, Perseveration, and Organization) developed to measure the executive aspects of ROCF productions. To assess the convergent and discriminant validity of the BQSS, these five scores were compared to scores on four traditional tests of executive functioning, as well as to three non-executive measures, in 141 adult patients. BQSS executive variables significantly correlated with the traditional executive measures and were less correlated with discriminant measures. The BQSS Organization summary score also significantly differentiated patients with either no, mild, or severe executive dysfunction. These results support the construct validity of the BQSS and demonstrate that the ROCF may be a useful measure of executive functioning. [ABSTRACT FROM AUTHOR]

The California Verbal Learning Test (CVLT) and the Logical Memory (LM) subtest from the Wechsler Memory Scale-Revised (WMS-R) are generally thought to be interchangeable measures of verbal memory. However, little is known about the effects of executive dysfunction on these tasks. The present study involved 96 patients referred for neuropsychological evaluation who were classified as having either significant executive dysfunction (SED) or minimal executive dysfunction (MED) based on the number of impaired executive tasks. Results showed that the SED group performed significantly worse on CVLT total words learned and most of the recall conditions compared to the MED patients (p < .01). However, performance on both immediate and delayed LM did not significantly differentiate the groups. CVLT measures of semantic clustering, perseveration, intrusions, and false positive errors did not appear to account for the group differences. The current study strongly suggests that the CVLT and the LM subtest are differentially associated with executive dysfunction, and argues for the inclusion of both types of tasks in a comprehensive neuropsychological evaluation. [ABSTRACT FROM AUTHOR]

The authors hypothesized that HIV-infected men with high basal cortisol se cretion would exhibit greater stress-related reductions in the ratio of Th1/Th2 cell-derived cytokines and numbers of CD8[sup +] T and NK lymphocytes than low basal cortisol secretors. A semistructured interview was used to assess life stress during the preceding 6 months of 94 HIV-infected men classified as high and low cortisol secretors (n = 47/group). Increased levels of severe life stress were highly correlated with lower numbers of CD8[sup +] T cells, CD16[sup +] and CD56[sup +] NK cells, CD57[sup +] cells, and higher DHEA-S concentrations in the high cortisol group. Conversely, no significant correlations were found in the low cortisol group. No correlations were found between stress and CD4[sup +] T helper/ inducer cell counts, cytokine production, or testosterone levels in either participating group. These data suggest that severe stress in combination with high glucocorticoid activity may modify select parameters of im mune status in HIV-infected men. [ABSTRACT FROM AUTHOR]

BackgroundMethodsResultsConclusionsFormer professional collision sport (CS) athletes, particularly American football players, are at risk of developing chronic health conditions; however, little is known about the health outcomes of amateur athletes.A 60-item health survey examined self-reported symptoms and diagnoses among former Division 1 Collegiate CS athletes and non- or limited-contact sport (non-CS) athletes. Binary logistic regressions tested the association between playing CS and health outcomes.Five hundred and two (6.2%) participants completed the survey: 160 CS athletes (mean age: 59.2, SD = 16.0) and 303 non-CS athletes (mean age: 54.0, SD = 16.9). CS athletes had increased odds of reported cognitive complaints and neuropsychiatric symptoms including memory (Padj < 0.01), attention/concentration (Padj = 0.01), problem solving/multi-tasking (Padj = 0.05), language (Padj = 0.02), anxiety (Padj = 0.04), impulsivity (Padj = 0.02), short-fuse/rage/explosivity (Padj < 0.001), and violence/aggression (Padj = 0.02). CS athletes also reported higher rates of sleep apnea (Padj = 0.02). There were no group differences in cardiovascular and physical health outcomes.Former CS athletes reported more cognitive and neuropsychiatric complaints. The low response rate is a limitation of this study; however, over 500,000 athletes play college sports each year, thus research on long-term health outcomes in this population is critical. [ABSTRACT FROM AUTHOR]

Rey-Osterrieth Complex Figure (ROCF) productions from 18 adults with Attention Deficit Hyperactivity Disorder (ADHD) were compared to 18 matched controls using the Boston Qualitative Scoring System (BQSS). ADHD adults showed impairment in measures of configural accuracy, planning, and neatness. A logistic regression model resulted in 75% sensitivity and 81% specificity in discriminating ADHD from control subjects. In contrast, there was no significant difference on the traditional ROCF 36-point score, and the sensitivity and specificity for the 36-point score were lower (68% and 71%, respectively). These findings suggest persisting executive dysfunction in adults with ADHD that can be detected in ROCF productions. Thus, the BQSS may be a useful tool contributing to the neuropsychological evaluation of adults with ADHD. [ABSTRACT FROM AUTHOR]

Examines the visual analog mood scales (VAMS) to assess mood disturbance in neurologically impaired patients. Evaluation on communication and cognitive deficits; Use of computer graphics to produce VAMS cartoon faces; Emphasis on vertical orientation to avoid response distortions due to hemispatial neglect of hemianopsia.

Presents a study focusing on geology education and the explanation of subduction zones to students in introductory-geology classes. How subduction zones are characterized; Reference to numerical experiments done by Davies and Stevenson (1992); Details on the thermal structure of subduction zones; In-depth look at the study; Conclusions of the study.

A questionnaire of 33 items concerning reactions to stressful situations was administered to samples of French, American, Filipino, and Haitian college students. Differences in reported frequency were found for sex, level of industrialization, language, and nationality. Factor analyses of the total sample and of male and female national samples revealed cultural differences in patterns of reaction with French speakers showing different combinations of physical and cognitive disruptions. [ABSTRACT FROM AUTHOR]

We have used the Michigan Model of World Production and Trade to assess the impact of exports and imports of armaments (based on 1980 data) on sectoral trade and employment and other economic variables in the major Western trading countries. If the United States were to place a unilateral embargo on its arms exports and imports, we calculate that it would experience a comparatively small amount of employment displacement in the aggregate and that most of this displacement would occur in the transport equipment and electric machinery sectors. If all the major Western countries were to place a multilateral embargo on their arms trade, the sectoral effects on the United States would be similarly small. But the sectoral effects in several other industrialized and developing countries measured as a percentage of sectoral employment, would be larger, indicating potential short‐run adjustment problems in labor markets in some cases. [ABSTRACT FROM PUBLISHER]