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Here new evidence of the isotope geochronology and the geochemistry from the Yuanmou-Miyi complexes reveal the Precambrian tectono-magmatism geodynamic process in the study area. The Yangtze Block basement with 1.81- ~1.77 Ga and negative εHf(t) values of −7.8 to −0.7 corresponded to the assembly of the Columbia-supercontinent. However, the rifting magmatic event of ~ 1.70 Ga, which caused the continental crust extension-thinning in the study area, may exert influence on the subduction-magmatism in the Grenvillian period. The Yuanmou-Miyi complexes of 1.19- ~1.00 Ga are characterized by (La/Sm)N＞1, depletion in HFSEs, negative anomalies of Nb-Ta, and enrichment of LILEs, which show a genetic link with the subduction-magmatism. The temporal tendency that the magmatism from Yuanmou to Miyi gradually became younger, may be responsible for the subducting direction. The subduction caused the reactivation of the Anninghe-Lvzhijiag fault zone, and created the rupture windows of the subduction slab, leading to upwelling of the deep magma. These granitoids were derived from the partial melting of the mantle wedge, while the small-scale gabbro dikes intruded into the granitoids were likely spillover products from the asthenosphere mantle melts through the rupture windows. [ABSTRACT FROM AUTHOR]

Finite commutative semifields of odd characteristic correspond to Dembowski-Ostrom polynomials. A new proof of this fact is the main result of this paper. The paper also discusses strong isotopy of commutative semifields and shows that the limit on the number of strong isotopy classes can be obtained from a general theorem on commutative loops. By this theorem for each commutative loop Q the commutative isotopes form at most | N μ : (N μ) 2 N λ | classes with respect to the strong isotopy, where N μ and N λ are the middle and the left nucleus of Q. Loops Q1 and Q2 are said to be strongly isotopic if there exists an isotopism Q 1 → Q 2 of the form (α , α , γ) . [ABSTRACT FROM AUTHOR]

There are 25 Li-rich geothermal fields (>15 mg/L) are displayed throughout nine geothermal zones in Tibet. The Kawu geothermal system is one of the representative high-enthalpy and Li-rich geothermal systems and is located in the Skaya dome, the Himalayas. Their boiling and hot and cold waters are Cl-HCO3-Na and HCO3-Ca types, respectively. The parent geothermal fluids are characterized by high Na, Cl, B, Si, As, Li, Rb+, Cs+ and F, and the Cl− concentration and enthalpy of the parent geothermal liquid are 515 mg/L and 1,485 J/g, respectively (corresponding to a temperature of 323.5°C). The stable oxygen and hydrogen isotopic compositions of geothermal fluids range from −19.7 to −23.4‰ and −155 to −181.2‰, indicating that the ratio of magmatic water mixed into geothermal fluid is between 11.7% and 19.5%. The lithium content in the geothermal system is high (13.04 to 20.8 ppm), but the δ7Li is relatively low (1.06 to 1.72‰). The high Cl, Li and B contents, constant Cl/Li and Cl/B ratios and low δ7Li indicate that they mainly originate from magmatic fluid, rather than from water rock reaction with the leucogranite and gneiss. While ascending from the reservoirs to the surface, the parent geothermal fluids gradually mixed with the meteoric waters infiltrated via brittle tensional small-scale faults, in turn forming four cooling processes upwelling patterns, i.e. conductive cooling, adiabatic cooling, mixing with cold water, and the combination of these processes. [ABSTRACT FROM AUTHOR]

Foliage uptake of atmospheric elemental mercury (Hg0) and subsequent translocation by the phloem is the main pathway for Hg accumulation in tree rings. Tree rings have been used as the emerging natural archive to directly reconstruct centennial trends of atmospheric Hg0 level. The tree-ring Hg records in remote regions have successfully reconstructed the peak of anthropogenic Hg emissions in Europe and North America in 1960s − 1970s and the distinct increase of Hg emissions in Asia since 1980s. Combining the Hg concentrations and isotopic signatures would provide historical atmospheric Hg trends and Hg emission source shifts. The mechanisms for Hg translocation, specifically the radial translocation and impacts of environmental and tree physiological factors, are yet to be clarified to explain the nonlinear relation between atmospheric Hg0 concentration and Hg signals in tree rings. Thus, we recommend to trace Hg accumulation and translocation processes and their Hg isotopic fractionation in tree rings, and examine the relationship between tree-ring Hg profile and atmospheric pollution level in specific tree species. Finally, we suggest to develop more statistical models to quantify environmental and tree physiological impacts on Hg accumulation and translocation in tree rings. [ABSTRACT FROM AUTHOR]

This study aimed to develop prognostic prediction models for patients diagnosed with synchronous thyroid and breast cancer (TBC). Utilizing the SEER database, key predictive factors were identified, including T stage of thyroid cancer, T stage of breast cancer, M stage of breast cancer, patient age, thyroid cancer surgery type, and isotope therapy. A nomogram predicting 5-year and 10-year survival rates was constructed and validated, exhibiting strong performance (C-statistic: 0.79 in the development cohort (95% CI: 0.74-0.84), and 0.82 in the validation cohort (95% CI: 0.77-0.89)). The area under the Receiver Operator Characteristic (ROC) curve ranged from 0.798 to 0.883 for both cohorts. Calibration and decision curve analyses further affirmed the model's clinical utility. Stratifying patients into high-risk and low-risk groups using the nomogram revealed significant differences in survival rates (P < 0.0001). The successful development and validation of this nomogram for predicting 5-year and 10-year survival rates in patients with synchronous TBC hold promise for similar patient populations, contributing significantly to cancer research. [ABSTRACT FROM AUTHOR]

The end of the Cryogenian glaciations undoubtedly affected the chemistry of the Neoproterozoic oceans, with potential consequences for the evolution of life; the duration and extent of this influence are poorly constrained. Lithium (Li) isotopes in carbonates can be used to investigate past weathering events and riverine input into the oceans. Here, we report the Li isotope (δ7Li) composition of the Ediacaran cap dolostones (Marinoan) from the Nuccaleena Formation, South Australia and the Doushantuo Formation, South China to investigate changes in weathering during the aftermath of the Marinoan glaciation. The origin of dolomite formation is still hotly debated, and the inability to precipitate dolomite at ambient temperatures (the 'dolomite problem') has not yet been resolved. The dominant hypothesis for the presence of marine dolomite is that it is of secondary origin, owing to diagenetic replacement of calcium carbonate, but a second hypothesis is that it forms as a result of primary marine deposition; both are plausible hypotheses. Using carbon isotopes (δ13C) and ratios of manganese and strontium (Mn/Sr), we suggest that diagenesis may not have significantly altered the δ7Li composition of the primary dolomite, but this cannot be discounted without further diagenetic modelling. As a result, we cannot infer the δ7Li composition of the Ediacaran oceans, as further work must be done to address the impact of diagenesis on the δ7Li values. Nevertheless, this dataset contributes to a Li isotope chemostratigraphic record of the Proterozoic, which is a key element to understanding the emergence of complex life. [ABSTRACT FROM AUTHOR]

The composition of trench sediment at convergent margins exhibits strong compositional links to the corresponding arc magmas. To test for the existence of such links at the Hikurangi margin, we provide a first geochemical characterisation of the IODP sites U1518 and U1520 drilled at the upper and incoming plate respectively. The identification of a décollement in the trench sediments allows distinction of the accreting clastic sediment above the décollement and the subducting pelagic and volcaniclastic material below it. The accreted material and that located above the décollement show homogenous Pb, Sr and Nd isotope ratios with bulk compositions of 206Pb/204Pb: 18.8953, 207Pb/204Pb: 15.6552, 208Pb/204Pb: 38.8371, 87Sr/86Sr: 0.70935, 143Nd/144Nd: 0.51241. In contrast, the material located below the décollement shows more heterogeneous Pb-Sr-Nd isotope ratios and bulk compositions of 206Pb/204Pb: 20.4826, 207Pb/204Pb: 15.7355, 208Pb/204Pb: 39.9833, 87Sr/86Sr: 0.70752, and 143Nd/144Nd: 0.51286. Tectonic erosion in the Hikurangi margin implies that accreted material could subsequently be subducted from the underside of the upper plate. Therefore, this characterisation is of prime importance for future work to constrain the role that subducted materials play in the compositional variations of the arc magmatism associated with subduction along the Hikurangi margin. [ABSTRACT FROM AUTHOR]

This paper introduces the concept of multi-locality as a relational approach to past gendered mobility and identities. Multi-local individuals are identified through strontium isotope analyses when the isotopic ratios are seen to change over the course of an individual life. The study is focused on the social institutions intersecting with mobility and a wish to examine how mobility is related to age and gender in multi-local individuals. A focus on when and why mobility occurs in life adds a much-needed social perspective on mobility to supplement the current dominating focus on provenance. By introducing five cases of multi-local individuals from the Nordic Bronze Age, it is demonstrated that several social institutions could cause age-related gendered mobility patterns. It is proposed that many of these institutions were shared between the gender categories of female and male, such as marriage, fosterage, trade and socio-political mobility (e.g. ritual activity and xenia). In conclusion, it is suggested that additional kinship models could be considered for the Nordic Bronze Age in addition to the predominantly accepted model of patrilocal exogamy. [ABSTRACT FROM AUTHOR]

Shallow crystalline groundwater in the semi-arid hinterland of Ceará is brackish or saline with mixed chloride or sodium chloride facies. Very few hydrochemical data are available for the area and the drivers behind this salinity are not clearly identified. In this study, extensive field data collection was performed to provide new information about the hydrogeological functioning and the salinization processes, through the implementation of piezometric, hydrogeochemical, isotopic ( 18O, ²H) and multitracer dating (14C, ³H, CFC, SF6) monitoring. Piezometric and isotopic data evidence fast flow circulation processes and a high contribution of evaporated surface water to aquifer recharge. Multitracer dating shows the groundwater is essentially composed of seasonal vertical infiltration flows that mix with older waters stored in the aquifer. Chemical analyses suggest the groundwater, originally low mineralized, has become progressively saltier due to leaching of salts that were evapoconcentrated in either surface waters or the unsaturated zone during drier periods. [ABSTRACT FROM AUTHOR]

THE PROCUREMENT AND TRADE OF VALUABLE 'outland' resources was fundamental to the early medieval economy, linking upland, forested and coastal regions with emerging urban markets. Recent research has detailed the increased exploitation and production of raw materials, including tar, soapstone, iron and antler, in the centuries prior to and during the Viking Age, primarily within Scandinavia. Here, it is argued from new isotope data relating to lead from 9th- to 11th-century York that there was an additional, international trade in a valuable but non-precious outland resource. Lead mined from the North Pennines was exported across the North Sea on a significant scale, connecting the remote uplands of northern England with urban nodes including York, Kaupang (Norway) and Hedeby (Germany; historically Denmark). We argue that North Pennines lead was part of a wider early medieval English lead export industry that operated from at least the mid-8th century ad. [ABSTRACT FROM AUTHOR]

Banded iron formations (BIFs) are widespread over the world (3.81 Ga to 1.80 Ga) as the Algoma and Superior types. The paper provides new isotope (Nd-Sr, U-Pb) data on associated noble-metal mineralization in Algoma-type BIFs of the Fennoscandian Shield. U-Pb dating of accessory zircon applied to estimate the formation time of noble-metal-bearing skarn and related rocks in the Olenegorsk and Kirovogorsk BIFs, NW Fennoscandian Shield show that they occurred in the interval between the formation of basalt protolith (2.81 Ga amphibolites) and metamorphism in BIFs (2.75 Ga) to the formation of gold-bearing iron-rich skarn with native Au, Ag, Bi and tellurides (2.65 Ga) and low-temperature quartz-zeolite veins with redeposited Au (2.55 Ga). REE distribution in zircons and corresponding rocks indicated an important role of redox reactions in Fe and REE redistribution affected by reducing fluids on haematite-quartz protolith of BIFs. [ABSTRACT FROM AUTHOR]

Cambrian igneous rocks in the Takaka Terrane of New Zealand provide important constraints for geodynamic reconstructions of the Cambrian SE Gondwana margin. We provide field data and a comprehensive trace element and isotope dataset for such rocks from the upper Baton River area in northwest Nelson, New Zealand, including the first combined Hf-Nd isotope data for Takaka Terrane rocks. These submarine volcanic rocks, known as Mataki and Benson volcanics of the Devil River Volcanics Group, are both interbedded with Haupiri Group sediments, providing a previously not observed direct stratigraphic link between the two volcanic units. Incompatible element abundances of Mataki Volcanics display a full spectrum from subduction-modified back-arc-tholeiites to E-MORB type tholeiites. Initial Hf-Nd isotope compositions are coupled, spanning a range from MORB-like to OIB-like compositions. The MORB-like endmember (initial ϵNd +7 and ϵHf +13), taps moderately depleted asthenospheric mantle. If extrapolated to present-day composition, this depleted mantle endmember does not resemble modern Pacific-type mantle, suggesting formation in a back-arc basin separated from Pacific mantle by a continent-ward, intra-oceanic subduction zone. The enriched asthenospheric mantle endmember in the Mataki Volcanics may be an equivalent to the sources of Neoproterozic or middle Cambrian intra-continental flood basalts in central and SE-Australia. [ABSTRACT FROM AUTHOR]

Abstract Foliage uptake of atmospheric elemental mercury (Hg0) and subsequent translocation by the phloem is the main pathway for Hg accumulation in tree rings. Tree rings have been used as the emerging natural archive to directly reconstruct centennial trends of atmospheric Hg0 level. The tree-ring Hg records in remote regions have successfully reconstructed the peak of anthropogenic Hg emissions in Europe and North America in 1960s − 1970s and the distinct increase of Hg emissions in Asia since 1980s. Combining the Hg concentrations and isotopic signatures would provide historical atmospheric Hg trends and Hg emission source shifts. The mechanisms for Hg translocation, specifically the radial translocation and impacts of environmental and tree physiological factors, are yet to be clarified to explain the nonlinear relation between atmospheric Hg0 concentration and Hg signals in tree rings. Thus, we recommend to trace Hg accumulation and translocation processes and their Hg isotopic fractionation in tree rings, and examine the relationship between tree-ring Hg profile and atmospheric pollution level in specific tree species. Finally, we suggest to develop more statistical models to quantify environmental and tree physiological impacts on Hg accumulation and translocation in tree rings. [ABSTRACT FROM AUTHOR]

Water isotopes (δ18O, δ2H) were systematically monitored in two river catchments to investigate the isotopic spatiotemporal variation and the differences between them. The Pinios River Basin (PRB) exhibited lower average δ18O and δ2H values (−7.9‰ and −50.8‰, respectively) compared to the Evrotas River Basin (ERB) (−6.5‰ and −38.2‰, respectively) but higher in range (3.3‰ vs 1.2‰ for δ18O, respectively). The Bayesian modelling results showed higher groundwater contribution in the PRB (25–50%) than in the ERB (15–35%) relative to precipitation during the wet period. The isotopic spatial variability was attributed to the influence of local precipitation, evaporation and additional flow pathways (e.g. soil water). The correlation analysis showed that the isotopic composition is controlled by the catchment altitude, slope and discharge. This study highlights the catchment physiographic control on the isotopic composition of rivers, which can support strategies for better water resources management. [ABSTRACT FROM AUTHOR]

We analysed the stable isotope compositions of dinosaur eggshells and their associated depositional settings of the egg-bearing rocks in the Upper Cretaceous of the Qiyunshan area, Anhui Province, China. Data show that δ13C values for Similifaveoloolithus qiyunshanensis and Umbellaoolithus xiuningensis range between −5.94‰ and −3.55‰; this suggests that C3-type vegetation was consumed by dinosaurs with relatively high atmospheric CO2. δ18O values vary between −8.45‰ and −4.95‰, indicative of high temperature and low humidity within nesting areas. The lithological characteristics of the egg-bearing section evaluated in this study are dominated by red-brown fine sandy siltstone, correlating with pebbly medium-fine grained and medium-fine grained lithic sandstones. Grain size parameters, histograms, and sample probability cumulative curves are also all characterised by fine-grained sediments and suspension populations, likely indicative of floodplain and point bar environments. Therefore, the paleoclimate of the dinosaur nesting habitat was semiarid-to-arid based on food types as well as the colour and high Fe content of sediments. We suggest that this fluvial environment provided the best nesting and egg laying area for drought-adapted dinosaurs in the Upper Cretaceous of the Qiyunshan area and that the excavated nesting could be concluded in view of the periodic flooding events. [ABSTRACT FROM AUTHOR]

Cross sections for the 141Pr(α,x) 144,143,141Pm, 138mPr, 141cum,140cumNd, and 139cumCe reactions were measured by the stacked foil technique at an alpha-particle range of 60 to 20 MeV. Most of the data were obtained for the first time. Experimental data were compared with earlier research and theoretical values from the TENDL-2021 database. Thick target yields of activation products were calculated. The reaction 141Pr(α,5n)140Pm (9.2 s)→140Nd was compared with other 140Nd production routes. [ABSTRACT FROM AUTHOR]

The occurrence of volcanic basanite cobbles in Pleistocene terraces at Galloway and in the upper Clutha valley in Central Otago, in an area devoid of known volcanic edifices, has implications for Cenozoic intraplate volcanism and Pleistocene drainage in the region. We present petrographic, mineralogical, whole rock geochemical and Sr-Nd-Pb isotopic data, as well as an 39Ar-40Ar date of 24.4 ± 0.06 Ma, together with mineral analyses of enclosed peridotite xenoliths. We conclude from this dataset that these alkaline basanite cobbles are most likely derived from the Alpine Dike Swarm in northwest Otago, probably in the Lake Wanaka-Hawea-Luggate area, which extends the volcanic field east of its known extent. The pilotaxitic textures and presence of intersertal glass, along with the volume of basanitic material, suggests that the source rocks were likely effusive, which would make this the first such known component of the Alpine Dike Swarm and requires emergent land at that time. The occurrence of the Galloway basanite cobbles implies that Pleistocene Clutha River flowed through or over what is now the Dunstan Range. The young (late Pleistocene) age of all the basanite-bearing gravels means that the basanite cobbles have likely been reworked several times before final deposition. [ABSTRACT FROM AUTHOR]

The Almogholagh Intrusive Complex (AIC) in the central part of the Sanandaj-Sirjan zone (C-SaSZ) includes gabbros to granites. Zircon U-Pb dating of mafic, intermediate, and felsic intrusions yield age of 146 to 141 Ma (Late Jurassic-Early Cretaceous). Bulk chemistry shows a wide range for SiO2 (46.8 to 73.3 wt.%), MgO (0.08 to 8.95 wt.%), and Fe2O3(T) (0.47 to 9.25 wt.%) and also alkali elements ranging from 3.59 to 10.12 wt.%. These rocks are characterized by a high content of large-ion lithophile elements (LILEs; e.g. Rb, U, Th, and K) and LREEs with weak Nb and Ta negative anomalies, showing many similarities to an extensional setting. The 176Hf/177Hf ratios vary from 0.282802 to 0.282985 with positive εHf(t) values from + 1.67 to +10.74 (avg: 7.85). Trace-element and isotope ratios modelling indicate that the AIC mafic-intermediate rocks were generated by partial melting of spinel lherzolite and then underwent considerable crustal contamination. The present work in combination with previous data confirm an extensional tectonic regime for the northern part of the C-SaSZ during the Late Jurassic to Early Cretaceous. Magmatic differentiation with crustal contamination played a fundamental role in the wide compositional range from mafic to felsic types that formed the AIC. [ABSTRACT FROM AUTHOR]

A wide variety of deposit types formed in the late Palaeozoic-Mesozoic of eastern NE China and adjacent Russian Far East of the eastern Central Asian Orogenic Belt (CAOB). However, outstanding questions remain on the (1) number of magmatic and metallogenic phases, and their respective space–time distribution; (2) geochemical (incl. isotopic) signature and fertility of each magmatic phase; and (3) tectonic link with these magmato-metallogenic events. We present new data (zircon U-Pb dating, geochemistry, and Sr-Nd isotopes) on the Yangjingou W and Xiaoxi'nancha Au-Cu deposits, and compile published data from major ore deposits in the region. We have newly summarized four magmato-mineralization phases: (1) Middle Permian (ca. 273–259 Ma) Cu-Au-Pb-Zn, (2) Latest Permian-Early Triassic (ca. 253–247 Ma) W-Cu-Mo-Au, (3) Earliest-Middle Jurassic (ca. 201–162 Ma) Mo-Au-Fe-W-Pb-Zn, and (4) Cretaceous (ca. 129–83 Ma) W-Sn-Mo-Cu-Au mineralization. Cretaceous ore-causative granitoids are mainly I-type arc-related, whereas those for the three older mineralization phases are largely adakite-like or adakite-normal arc transitional. These granitoids were mostly derived from partial melting of juvenile crust, and to a lesser extent from a mixture of juvenile and ancient crust. We propose that the Middle Permian subduction of the Paleo-Asian and Panthalassa oceans formed the Au/Cu-Pb-Zn skarn and cryptoexplosive breccia-hosted Pb-Zn ± Ag deposits. Subsequently, the latest Permian-Early Triassic Paleo-Asian Ocean closure likely formed the porphyry-skarn Cu-Mo, orogenic Au, and vein-type W deposits in the Songliao and eastern Liaoyuan terranes. In the Early-Middle Jurassic, Paleo-Pacific subduction may have formed the Jiapigou orogenic Au belt and the Fe-polymetallic skarn deposits in the northern Songliao terrane, as well as porphyry Mo deposits along the Mudanjiang fault. Subsequently, Cretaceous W-Sn-Au-Cu metallogeny was controlled by Paleo-Pacific subduction rollback, and in the Russia Far East by partial melting of redox accretionary complexes. [ABSTRACT FROM AUTHOR]

The aim is to examine the nutrient ion dynamics in a Vertisol soil undergoing waterlogging to ascertain whether soil solution concentration and/or nutrient uptake dynamics are the cause of boll shedding in cotton. Cotton was grown in pots, and the soil waterlogged after 76 days at which time injections of 33P and 86Rb were made to trace phosphorus (P) and potassium (K) dynamics. After seven days, waterlogging in the pots were drained and an injection of 32P was made to trace P dynamics during the recovery period. Redox fell rapidly during waterlogging, and soil solution concentrations of P, K, sodium (Na), and manganese (Mn) increased. Biomass accumulation was less in the waterlogged treatment than in the non-waterlogged control. In the 7-day recovery period, shoot biomass increased in the waterlogged treatment and root biomass weight continued to decline. Recovery of 33P was 10 times higher in the control than in the waterlogged treatment during the 7-day waterlogging period treatment. Uptake of 86Rb in the control treatment was more than twice that of the waterlogged treatment during this period. Uptake of both33P and 86Rb increased during recovery but remained higher in the control treatment. Uptake of 32P occurred during post-waterlogging but remained higher in the control treatment. Reduced uptake of P and K during waterlogging is most likely due to damage to the uptake mechanisms of the roots rather than a reduction in the concentration of nutrients in the soil solution under waterlogged conditions. [ABSTRACT FROM AUTHOR]

The Archaean crustal evolution of the northern São Francisco Craton (SFC) reveals significant similarity with Kaapvaal-Zimbabwe and Pilbara, cratons, especially before 3.0 Ga. Likewise, compiled geochronological and Nd-Sr-Hf isotope data suggest that the Archaean blocks of the northern part of SFC (e.g. Gavião, Uauá and Serrinha) shared similar crustal evolution since 3.15 Ga. The 3.42–3.35 Ga TTGs of the southern and western Gavião Block have negative and slightly positive ɛNd(t) and ɛHf(t) values and TDM(Hf) ages between 3.50 and 3.90 Ga, indicating that they were produced by partial melting of Eoarchaean to Palaeoarchaean crust, with minor mantle sources. The ca. 3.30 Ga high-silica plutonic-volcanic system, which is related to intraplate magmatism and intracrustal differentiation processes, would represent processes of continental rifting and break-up. In the northern Gavião Block, the 3.64 Ga migmatite-gneiss paleosomes with negative ɛHf(t), 176Hf/177Hf ratio between 0.2802 and 0.2805 and TDM(Hf) ages between 3.75 and 4.15 Ga of the Mairi Complex represent the oldest dated rocks of the whole São Francisco Craton, suggesting late Hadean and Eoarchaean sources. The 3.15 and 3.00 Ga rocks of the Serrinha Block have positive ɛNd(t) values, suggesting a predominant juvenile source. Likewise, coeval 3.15 and 3.00 Ga Uauá Block rock assemblage has slightly positive to negative ɛNd(t) values, which indicate mixing of crustal and juvenile sources. The 2.90 to 2.77 Ga period in the SFC is characterized by pervasive crustal anatexis with high-K granite generation, similar to Kaapvaal and Pilbara cratons. Therefore, Archaean migmatite-gneiss terrains recorded four crustal differentiation intervals (e.g. 3.66–3.51, 3.45–3.30, 3.15–3.00 and 2.90–2.77 Ga) in the São Francisco Craton. [ABSTRACT FROM AUTHOR]

Stable isotope ratios of nitrogen and oxygen (15N/14N and 18O/16O) of nitrate (NO3–) are excellent tracers for developing systematic understanding of sources, conversions, and deposition of reactive atmospheric nitrogen (Nr) in the environment. Despite recent analytical advances, standardized sampling of NO3–) isotopes in precipitation is still lacking. To advance atmospheric studies on Nr species, we propose best-practice guidelines for accurate and precise sampling and analysis of NO3– isotopes in precipitation based on the experience obtained from an international research project coordinated by the International Atomic Energy Agency (IAEA). The precipitation sampling and preservation strategies yielded a good agreement between the NO3– concentrations measured at the laboratories of 16 countries and at the IAEA. Compared to conventional methods (e.g., bacterial denitrification), we confirmed the accurate performance of the lower cost Ti(III) reduction method for isotope analyses (15N and 18O) of NO3– in precipitation samples. These isotopic data depict different origins and oxidation pathways of inorganic nitrogen. This work emphasized the capability of NO3– isotopes to assess the origin and atmospheric oxidation of Nr and outlined a pathway to improve laboratory capability and expertise at a global scale. The incorporation of other isotopes like 17O in Nr is recommended in future studies. [ABSTRACT FROM AUTHOR]

Late Mesozoic felsic volcanic rocks are mostly distributed in the Zhejiang, Fujian, and Guangdong provinces, southeastern China, with an outcrop area of >100,000 km2. Although many studies have been published, however, the petrogenesis and tectonic background of these felsic volcanic rocks have remained controversial. Here, we present nineteen new SHRIMP U-Pb zircon ages and Lu-Hf isotopes of the felsic volcanic rocks from southeastern Zhejiang Province. The studied samples have zircon U-Pb ages range from 134 to 89 Ma and become younger towards the coastal zone. A group of zircons with U-Pb ages of 120–110 Ma have been documented, which argue against the proposed magmatic quiescence of 120–110 Ma in the study area. Together with all the published data, our zircon U-Pb mapping has shown that the lower volcanic series (140–120 Ma) are all distributed in the inland of Zhejiang Province, whereas the upper volcanic series (120–90 Ma) are mostly exposed in the coastal zone. Furthermore, nine felsic volcanic samples from Yandangshan area show negative correlation between the zircon ɛHf(t) values and the volcanic ages, which suggests the increased juvenile components in the source region with time. Our zircon Lu-Hf isotope mapping does not show a clearly trend towards the coastal zone. The variation of zircon Lu-Hf isotopes among felsic volcanic rocks were most likely attribute to the different degrees of juvenile contribution. Based on our new results, a episodic roll-back of the Palaeo-Pacific plate model can well explain the petrogenesis of the felsic volcanic rocks. There is no evidence supporting the scenario that a large volume of felsic magma erupted at a short interval of 3–10 Ma. Therefore, at least in Zhejiang Province, the Cretaceous felsic volcanic rocks cannot be considered as a part of a Silicic Large Igneous Province. [ABSTRACT FROM AUTHOR]

S-type granites constitute an important component of the Paleoproterozoic Khondalite Belt in the North China Craton. Here we present results from petrography, geochemistry and isotope geochronology on the porphyritic garnet-bearing syenogranite and garnet-bearing monzogranite samples in the Jining-Liangcheng area. The geochemical characteristics of these samples indicate formation through partial anatexis of the khondalites, with heat and material input from mantle-derived magma. Geochemical similarities between the porphyritic garnet-bearing syenogranite, garnet-bearing monzogranite, and metapelitic gneiss suggest their broad affinity. Sensitive high-resolution ion microprobe zircon U–Pb dating revealed that the S-type granites formed at ca. 1.92–1.90 Ga and were subsequently metamorphosed at ca. 1.85 Ga. The ca. 1.92–1.91 Ga porphyritic garnet-bearing syenogranite shows zircon εHf(t) values of −1.94–+3.38 with two-stage Hf crustal model ages (TDM2) ages of ca. 2.42–2.59 Ga. The 1.91–1.90-Ga garnet-bearing monzogranites show zircon εHf(t) values ranging from −4.36 to +0.38, with TDM2 ranging from ca. 2.57 to ca. 2.82 Ga. The geochemical isotopic compositions suggest that the porphyritic garnet-bearing syenogranite and garnet-bearing monzogranite originated from the partial melting of pre-existing crust of heterogeneous compositions with the addition of mantle-derived material. On the basis of our results, combined with geological data on the Paleoproterozoic structural evolution of the Khondalite Belt, we assume that the timing of the metamorphism and anatexis in the Jining–Liangcheng area is correlated with a regional metamorphism and mantle-derived magmatism. [ABSTRACT FROM AUTHOR]

Nitrate stable isotopes provide information about nitrate contamination and cycling by microbial processes. The Fischa-Dagnitz (Austria) spring and river system in the agricultural catchment of the Vienna basin shows minor annual variance in nitrate concentrations. We measured nitrate isotopes (δ15N, δ18O) in the source spring and river up to the confluence with the Danube River (2019–2020) with chemical and water isotopes to assess mixing and nitrate transformation processes. The Fischa-Dagnitz spring showed almost stable nitrate concentration (3.3 ± 1.0 mg/l as NO3–-N) year-round but surprisingly variable δ15N, δ18O-NO3– values ranging from +5.5 to +11.1‰ and from +0.5 to +8.1‰, respectively. The higher nitrate isotope values in summer were attributed to release of older denitrified water from the spring whose isotope signal was dampened downstream by mixing. A mixing model suggested denitrified groundwater contributed > 50 % of spring discharge at baseflow conditions. The isotopic composition of NO3– in the gaining streams was partly controlled by nitrification during autumn and winter months and assimilation during the growing season resulting in low and high δ15N-NO3– values, respectively. NO3– isotope variation helped disentangle denitrified groundwater inputs and biochemical cycling processes despite minor variation of NO3– concentration. [ABSTRACT FROM AUTHOR]

Stable water isotopes in ground-level vapour are key to estimating water exchange between geospheres. Their sampling, however, is limited to laser-absorption spectrometers and satellite observations, having inherent shortcomings. This study investigates diffusive kinetic fractionation during liquid condensation under supersaturated environment, providing a cost-effective, reliable way of sampling ground-level vapour isotopes (18O, 2H). Experiments were undertaken at three locations in India with 'liquid' samples collected from condensation of ambient air at 0°C. Simultaneously, pristine 'vapour' was sampled via cryogenic-trapping using liquid nitrogen–alcohol slush at –78°C. The 'liquid' condensed under supersaturation was progressively more depleted in 18O, and less enriched in 2H than expected under equilibrium fractionation, with an increasing degree of supersaturation expressed as saturation index (Si). This study revealed: (1) Si, molecular density, Rh, T together control the extent of isotopic kinetic fractionation. (2) The presence of diffusive concentration gradient inhibits the flow of heavier isotopes during liquid condensation. (3) The stochastic nature of the process cannot be explained using a physics-based model alone. The artificial neural network model is hence deployed to sample δ18O (δ2H) within –0.24 ± 1.79‰ (0.53 ± 11.23 ‰) of true value. (4) The approach can be extended to ground-validate isotope-enabled general circulation models and satellite observations. [ABSTRACT FROM AUTHOR]

The intermolecular potential energy surfaces (PESs) of Ne-CO complex have been constructed by using the CCSD(T)-F12a method with the aug-cc-pVQZ basis set. These PESs were subsequently applied to investigate the microwave and infrared spectra via bound state calculations. Firstly, compared to the available microwave data, the pure rotational transitions with K = 0 and J = 4 for this complex can be well reproduced. Furthermore, a set of accurate spectroscopic parameters were deduced for the fundamental (vCO = 1) and overtone (vCO = 2) bands. The vibrational shift for the normal isotopologue (Ne-12C16O) was determined to be -0.0683 cm-1, which is in excellent agreement with the experimental observation of -0.0711cm-1. Isotope effects were also investigated, and the determined rotational constants and vibrational shifts display a fairly good linear relationship, which is classified into two types according to the 12C and 13C in the CO monomer. [ABSTRACT FROM AUTHOR]

Nalameryx savagei is one of the rare mammals found in India during the Oligocene. Five dental remains composed the originally found material, described in 1990. The first phylogenetic hypothesis proposed Nalameryx to be closely related to the basal ruminant Lophiomerycidae. The description of new specimens from the type bed K/7b from the Kargil Formation (late Oligocene, India), led to a reinterpretation of the phylogenetic position of Nalameryx and of the early evolutionary history of the Tragulidae. Based on our phylogenetic hypothesis, Nalameryx is nested within the living Tragulidae, making it one of the oldest known tragulid. Moreover, the enigmatic late Eocene Stenomeryx from Myanmar is not recovered as a ruminant in our analysis. Tooth isotopic data indicate that Nalameryx fed on plants that have grown under xeric conditions. This is in agreement with palaeoenvironmental information observed on plants from Turkish and Pakistani localities where Nalameryx has already been found. This region of the world had a seasonal climate with an arid period during the late Oligocene. [ABSTRACT FROM AUTHOR]

The Bakoshi-Gadanya area, with widespread Neoproterozoic granites, is located within the Pan-African Trans-Sahara Belt, sandwiched between the West African and the Sahara metacraton. The whole-rock geochemistry, Sr-Nd isotope systematics and LA-(MC)-ICP-MS U-Pb-Hf isotopes of zircon were analysed to shed light on the age and genesis of the Bakoshi-Gadanya granites in the Precambrian basement of the northern western Nigeria shield. The granites are silicic (SiO2: 72.8–77.2 wt.%), ferroan, high-K, calc-alkalic to alkali-calcic in composition, with A-type granite affinities. The ferroan calc-alkalic types range in age from 706.6 ± 1 Ma to 638.4 ± 1 Ma, and the alkali-calcic type is dated at 710 ± 1 Ma. Whole-rock Sr-Nd and zircon Hf isotope systematics have constrained the ferroan calc-alkalic granites to an enriched mantle lithospheric magma source, contaminated by Archaean-Palaeoproterozoic crustal components. On the other hand, the magma that crystallized the alkali-calcic Gadanya granite originated from an enriched mantle source, triggered by reactivation of the lithosphere-scale Kalangai fault during the post 750 Ma major collision between West African Craton and the Saharan metacraton. Both alkali-calcic and calc-alkalic ferroan granites were formed contemporaneously with the last major Pan-African syn-metamorphic deformation in northern western Nigerian shield; thus, they are syn-kinematic granites. Neoproterozoic magmatism at Bakoshi-Gadanya area is related to easterly dipping subduction at the margin of microcontinental blocks in northern western Nigeria shield. Zircon U-Pb-Hf data envisaged both early Neoproterozoic and Cryogenian juvenile magmatic additions in this part of western Nigeria shield. [ABSTRACT FROM AUTHOR]

The number of studies using various stable isotope systems for tracing contamination sources and various biogeochemical processes is rapidly rising due to the increased availability of the techniques used for isotope analyses. However, in most cases, the resulting isotope data are influenced by many processes occurring within reactive environmental compartments, e.g., soils and sediments, such as sorption, precipitation, redox changes, interactions with plants and microorganisms, etc. Therefore, isotope tracing becomes challenging as it is crucial to identify and quantify the isotope fractionation extent during separate processes in this so-called "isotope fractionation black box". The main aim of this review is to (i) summarize literature data on fractionation of selected metal isotopes (Cd, Cu, Hg, Ni, Zn) after complexation with relevant environmental surfaces, e.g., oxyhydroxides, clay minerals, natural organic matter etc., (ii) briefly describe the analytical techniques and key procedures used for the determination of such data and (iii) provide suggestions and perspectives for future research, including a critical evaluation of specific issues related to isotope analyses and especially the interpretation of results. For example, concentration equilibrium usually differs from isotope fractionation equilibrium, metal coordination chemistry in solution is crucial to decipher metal isotopic fractionation, spectroscopic data are missing, different experimental conditions are often and potential precipitation and desorption reactions are not always considered, etc. Consistent presentation of adsorption/complexation data would also be highly beneficial in future studies. [ABSTRACT FROM AUTHOR]

On 2 May 2022, the new Facility for Rare Isotope Beams (FRIB) [[1]] at Michigan State University (MSU) was officially opened and the first experiment commenced on 9 May 2022. Estimated luminosity gain factors for experiments with fast rare-isotope beams by the using the planned HRS compared to spectrometers presently available at FRIB. Acknowledgments The author thanks the members of the HRS project team, the HRS working group, and members from the Facility for Rare Isotope Beams (FRIB) working groups that have contributed to the development of the HRS and its interface with other detector systems. [Extracted from the article]

New U-Pb zircon geochronology using high-spatial resolution secondary ion mass spectrometry fills a data gap and provides crystallization ages for granitoids from the Asir composite terrane in the southernmost Arabian Shield of Saudi Arabia. Ages of c. 810–685 Ma, c. 663–636 Ma, and 625–610 Ma reflect oceanic island arc genesis, subduction-related arc accretion (syn-collisional), and post-collisional stabilization, respectively. All samples have juvenile εNd(t) compositions with no evidence of older material being involved in their genesis, indicating that this part of the Arabian Shield grew through juvenile magmatic addition and that assimilation by syn- and post-tectonic magmatism involved an isotopically juvenile component(s). The crustal thickness derived from the (La/Yb)N proxy indicates significant thickening from 10–20 km to c. 70 km at c. 650 Ma, consistent with timing of orogenic uplift and increasing crustal thickness post-dating peak Nabitah orogeny. The age of an intrusion cross-cutting the Atura formation, when combined with other data, provides a well-constrained depositional age of c. 646–625 Ma for the Atura formation and indicates that erosion of the orogenic edifice in this part of the Arabian Shield began at latest by 625 Ma. Our new data indicate that denudation occurred 80–100 m.y. before the development of the prominent sub-Cambrian peneplain, consistent with previous assertions that major pulses of denudation occurred prior to the waning stages of Nabitah orogenesis. [ABSTRACT FROM AUTHOR]

The paper offers a double-cascade scheme for reducing the concentration of 232, 234, 236U isotopes in reprocessed uranium hexafluoride. The greatest decrease of the ratio between the masses of 236U and 235U is provided in the product of the first ordinary cascade enriched by 235U at the concentration of less than 20%. For this purpose, a special mode of stages operation is determined. Enrichment by 232, 234U is performed in the second ordinary cascade, which is fed by the product of the first cascade. After being purified from 232, 234U, the waste flow is diluted till the concentration of 235U is less than 5%. This paper describes the methodology for calculating the parameters of cascades with the stage separation factors correlating with gas centrifuges. This methodology served as a basis for a computational experiment. It is demonstrated that the output gained after the dilution meets the requirements of the American Society for Testing and Materials C996-20 specification for the commercial grade of lowenriched uranium hexafluoride in terms of 232, 234U isotopes. The content of 236U in it is several times less than during the direct enrichment of reprocessed uranium hexafluoride. [ABSTRACT FROM AUTHOR]

The peraluminous Foulwind and Windy Point Granites are important components of the Foulwind Suite – a diverse group of high field strength element-enriched Carboniferous granitoids in New Zealand's Western Province. Four phases are identified in the Foulwind Granite (Seal Point, Siberia Bay, Tauranga Bay, Lighthouse). A new age of 324.0 ± 4.1 Ma has been obtained for the relatively undeformed Siberia Bay phase. The rocks are generally enriched in high-field strength elements and the Tauranga Bay and Lighthouse phases can be classified as ferroan A-type granites, whereas classification of the other phases is ambiguous. Sr isotope compositions were disturbed by the formation of the Paparoa Metamorphic Core Complex. Nd isotopes vary considerably and indicate involvement of multiple sources. The Nd isotope and A-type signatures can be explained by melting of mid-Paleozoic I-type granites with variable involvement of Greenland Group metasediments. The tectonic setting of the Foulwind Suite is unclear, but may be related to processes subsequent to the generation of voluminous mid-Paleozoic granitoids and amalgamation of the Buller and Takaka Terranes. [ABSTRACT FROM AUTHOR]

North-central Ukraine is vulnerable to temperature increases and precipitation pattern changes associated with climate change. With water management becoming increasingly important, information on current water sources and moisture recycling is critically needed. Isotope ratios of oxygen (δ18O) and hydrogen (δ2H) in precipitation are sensitive to these variables and allow comparisons across the region. The δ2H and δ18O values from collected precipitation in Kyiv and Cherkasy in 2020 and published 3H data for Kyiv from the year 2000 show an influence of the North Atlantic Oscillation (NAO) and provide information about processes affecting precipitation along the storm trajectory. The δ18O values also show a correlation with temperature, indicating that precipitation patterns may be affected by the rising temperatures in the region, as predicted by recent regional studies using Representative Concentration Pathway scenarios and the global climate model GFDL-ESM2M. When compared to backtracked storm trajectory and NAO data, clear relationships emerged between water isotope ratios, storm paths, and likely moisture recycling. Overall, δ2H, δ18O, 3H, and backtracked storm trajectory data provide more regional and local information on water vapour processes, improving climate-change-driven precipitation forecasts in Ukraine. [ABSTRACT FROM AUTHOR]

The isotope biogeochemistry of bioindicators has widely demonstrated its added value in environmental issues by allowing to precisely identify sources of contamination. Most of the studies are based on studying one or two isotope systematics. Here, we are presenting an innovative multi-proxy approach that combines chemistry with both stable (C, S, N) and radiogenic (Pb) isotope systematics. Using Hypogymnia physodes bioindicators, we evaluated air quality in the complex environment of the Świętokrzyski National Park (ŚNP, Poland) with the ultimate objective of isotopically identifying the sources responsible for the observed contamination. Combining the isotope systematics showed that home heating is a major source of contamination in winter, whereas the contribution of road traffic increases during the summer. Pb isotope ratios identified industrial activities as the major source of this metal in the atmosphere. [ABSTRACT FROM AUTHOR]

Darwin's fox is an opportunistic omnivorous predator native to Chile classified as endangered by the IUCN Red List. Habitat use by Darwin's foxes can be negatively affected by the presence of free-ranging dogs that range freely across native and non-native habitats and can be a source of fox mortality. The objective of this study was to analyze the isotopic similarity of Darwin's fox and sympatric free-ranging dogs in Chiloé Island to determine the impact of anthropogenic environmental alterations on wild predators. We use hair samples to characterise and compare their δ13C and δ15N values and to evaluate isotopic similarity and isotope niches overlap. A generalised linear model was used to associate the isotope value with landscape variables (forest cover and vegetation type) and distance to the nearest house. We found no significant differences in δ13C or δ15N values between foxes and dogs, and a marginally significant isotope niche overlap (59.4 %). None of the selected variables at landscape and site scale were related to isotope values. Although our study is not a probe of direct contact between foxes and free-ranging dogs, the high isotopic similarity highlights the risk of pathogen spillover from free-ranging dogs to Darwin's foxes. [ABSTRACT FROM AUTHOR]

The IAEA/WMO session reviewed the present state of knowledge on the interpretation of climate variability by linking isotope hydrology and hydrometeorology, through bringing together meteorologists and hydrologists with and without isotope background. The Isotope Hydrology Section, International Atomic Energy Agency (IAEA), and the Department of Water and Cryosphere, World Meteorological Organization (WMO), conducted a virtual special session 'Better understand past, present and future climate variability by linking water isotopes and conventional hydrometeorology' at the 9th International Conference on Water Resources and Environment Research (ICWRER 2022) organised by the University of Central Florida, Orlando, USA. For climate change assessment, connecting water isotopes and conventional hydrometeorology will move forward the interpretation of climate variability and its impact if the following requirements are fulfilled: Development of novel techniques for automatic collection of atmospheric waters for stable and radioactive isotopes, Preservation of high-quality isotope data for long-term use in databases and the sample archiving, Development of new models to incorporate isotope hydrology into studies investigating climate changes and instabilities. [Extracted from the article]

It is our pleasure to introduce a special issue of Analytical Letters comprising selected papers presented at the 13th edition of International Conference on Processes in Isotopes and Molecules (PIM 2021) held between 22 and 24 September 2021 and organized by the National Institute for Research and Development of Isotopic and Molecular Technologies in Cluj-Napoca, Romania. The Conference brought together scientists from academia, research institutes, and industry to discuss their latest results. The scientific program was completed by exhibitors presenting latest equipment and services in the field of molecular and isotopic sciences. The PIM 2021 conference promotes the exchange of ideas, experience and knowledge between scientists and engineers, as well as to encourage collaborative interdisciplinary research activities. PIM 2021 provided a stimulating communication and discussion platform in a wide range of topics from fundamentals in physics and chemistry, to applied research on energy efficiency, environment, materials and isotopic technologies. [ABSTRACT FROM AUTHOR]

Weakly disseminated sulphide mineralization is present in the outcrops of several mafic–ultramafic intrusions in the Beishan region of the Central Asian Orogenic Belt in western China, but the potential of these intrusions to host economic sulphide ores at depths is not known. A better understanding of the genetic control on the mineralization may help to answer this important question. With this in mind, we have selected two of them that were emplaced during the Devonian, a period when subduction-related mafic magmatism undoubtedly occurred in the region, for a geochemical study. They are the Miaomiaojing and Guaishishan mafic–ultramafic intrusions. Our new zircon U-Pb dating indicates that they were emplaced at 377.5 ± 5.3 and 358.6 ± 3.9 Ma, respectively. Lherzolite, olivine websterite, troctolite and gabbro are the main rock types for both intrusions. Disseminated sulphide mineralization is concentrated in the ultramafic units of both intrusions. The whole-rock samples are characterized by light REE enrichments, pronounced negative Nb-Ta anomalies, and variable εNd(t) values from −3.54 to +2.17. Zircons from the intrusions have elevated δ18O values (average value: 7.48 ± 0.09 ‰) compared to that of the mantle. The trace element and isotope data support the interpretation that the parental magmas for the Devonian mafic–ultramafic intrusions are contaminated arc mafic magmas. Petrological modelling reveals that fractional crystallization together with crustal assimilation may have played an important role in triggering the sulphide saturation in the magmas. The Ni tenors (in recalculated 100% sulphide) for the sulphide-mineralized samples from both intrusions are similar and up to 6.7 wt% Ni and 2.8 wt% Cu, comparable to the metal tenor of most economic Ni-Cu deposits in the CAOB, implying that samples containing higher amounts of sulphides would become Ni-Cu ores. The olivine Fo and Ni contents from sulphide-bearing ultramafic rocks show a negative correlation, consistent with sub-solid Fe-Ni exchange between olivine and sulphide melt. Together with the similar mineralization characteristics between these sulphide-bearing intrusions and the coeval Heishan Ni-Cu deposit, we suggest that these intrusions have the potential to host Ni-Cu sulphide ores at depths, which could be further tested by geophysical survey followed by drilling. [ABSTRACT FROM AUTHOR]

Serving as a medium between source water and cellulose, leaf water contributes to the isotope ratios (δ18O, δ2H) of plant organic matter, which can be used for paleoclimate reconstruction. This study is the first to examine the diurnal variations in the δ18O and δ2H of leaf water on the southern Tibetan Plateau. The δ18O and δ2H of leaf water were relatively low when precipitation events occurred. In particular, 18O and 2H of leaf water became extremely depleted 5 h after the precipitation event. Our findings demonstrate that precipitation can modify the isotope ratios of leaf water from external and internal causes. First, precipitation events affect meteorological elements, lead to decreases in leaf transpiration, and immediately weaken the isotope enrichment of leaf water ('rapid effect' of precipitation). Second, precipitation events affect the internal plant–soil water cycle process, causing the plant to preferentially use deeper soil water, and the corresponding isotope ratios of leaf water exhibit extremely low values 5 h after precipitation events ('delay effect' of precipitation). This study suggests that researchers need to be cautious in separating the signals of precipitation and hydrological processes when interpreting isotope records preserved in tree-ring cellulose archives from the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

New umbellaoolithid and faveoloolithid eggs were discovered from the early Late Cretaceous deposit in the Xiuning Basin, Anhui Province, China, and the samples were examined for elemental and isotopic compositions to reconstruct the geochemical environment. The results show that the trace elements consist of Sr, Mn, Ti, Ba, As, La, Cr, Ni, Pb, Cu, Zn, Co and Ir. The abnormal Sr and Mn were deposited in the eggshell mainly through material exchange of dinosaurs, and the high Ir concentration of surrounding rocks in the Xiuning Basin is conformed to the early Late Cretaceous Ir anomaly. The δ13C compositions of eggshells suggest that the palaeovegetations are supposed to be −20.191‰ and −21.156‰ showing C3 plant and high CO2 concentration, as well as low mean annual precipitation. The δ18O compositions of eggshells indicate that the drinking water was mainly composed of meteoric water and plant leaf water, and the mean palaeotemperature was approximately 19°C. Based on the geochemical compositions of eggshells, the Ni content, the Sr/Ba ratio and the palaeoclimate index of surrounding rocks, the palaeoenvironment in the Xiuning Basin were dominated by alluvial fans and river systems with semi-arid climate in the early Late Cretaceous. [ABSTRACT FROM AUTHOR]

Separating Isotope Facts from Fallacies compares how intelligence agencies have performed in assessing the nuclear proliferation intentions of other countries. Using original archival and declassified documents from the Cold War era, the study appraises the accuracy of American, British, and West German intelligence proliferation assessments of India and Argentina. Contrary to pervasive scepticism, the available historical documentation shows that intelligence agencies did not habitually inflate their assessments of proliferation risks unless they anticipated arms race dynamics. Second, target state attitudes toward the nonproliferation regime provide essential clues to their nuclear intent. Third, more information about intentions did not inherently improve accuracy. [ABSTRACT FROM AUTHOR]

The common bully (Gobiomorphus cotidianus) was used as a bioindicator to assess the impacts of geothermal, bleached kraft mill effluent (BKME), sewage, and thermal discharges in the Waikato River, Northern New Zealand. A range of morphological and physiological parameters were measured to assess fitness in fish sampled upstream and downstream from these point sources. Isotopic signatures gave evidence that fish were resident at sites and showed a gradient corresponding to site-specific sources of carbon and nitrogen along the river. There were changes in the size range and age structure of the populations but, no physiological responses were detected. Limited impacts were observed on common bully health at individual discharge sites, or downstream where the river showed gradual deterioration in water quality, particularly nutrient enrichment, and increased turbidity. Despite the gradual deterioration in water quality no concomitant cumulative impacts were observed in common bully. Responses were largely local in nature, responding to point-source discharges. Population responses at the geothermal and BKME discharge sites warrant further study to investigate possible effects on fish recruitment. [ABSTRACT FROM AUTHOR]

Background: Since design and publication of the Western Aphasia Battery (WAB), increasing use to assess patients with aphasia in a clinical and research setting in stroke and in degenerative disease of the brain became evident. It has proven to be useful in determining the severity of and nature of the language impairment and providing clues for the location and function of the brain structures affected. Methods: Articles of WAB use were reviewed from the National Library of Medicine, Cochrane database under several headings of aphasia testing, stroke aphasia, primary progressive aphasia and others. Results: Available statistic indicated that the WAB is the most used comprehensive aphasia test. The overall severity score and quantitation of the components of the language impairment allows to define and classify aphasia, measure outcome in treatment modalities e.g., standard or constrained therapies, melodic intonation therapy, medications and transcranial stimulation and to study the linguistic features of aphasia and related cognition. Technological and scientific advances in neuroimaging from isotope scans to voxel-based morphometry, functional magnetic resonance and tractography uses the WAB for functional, anatomical and biological correlations of language. Conclusion: The acceptance of the WAB by researchers as well as clinicians appears to be related to the comprehensive measuring of essential and distinct language functions and practical length allowing it to be administered to a large variety of patients in diverse clinical and research conditions. [ABSTRACT FROM AUTHOR]

Lake Chalco is one of the few lakes in Mexico that has a long, continuous sedimentary sequence covering the Upper Pleistocene (> 150 000 yrs). The diatom content of its lacustrine sediments includes a variety of centric species. In particular, the sediments dating to Marine Isotope Stage 5 (MIS5) were alternately dominated by four Cyclotella spp: C. meneghiniana Kützing, C. quillensis Bailey, and two new species which are described here: C. poyeka and C. tlalocii. These two new Cyclotella spp. resemble C. stylorum Brightwell, because of the presence of marginal chambers. Nevertheless, the new species from Lake Chalco have a different structure of the marginal chambers and marginal fultoportulae with three satellite pores. Cyclotella poyeka and C. tlalocii differ from each other by the relative proportion of the central area to valve face diameter, the central fultoportula arrangement, and the striation pattern. Ecological affinities of the four Cyclotella species in the MIS5 sediments from Lake Chalco are discussed based on their modern distribution (for C. meneghiniana and C. quillensis) and their fossil assemblages (for C. quillensis, C. tlalocii and C. poyeka), leading to the conclusion that C. tlalocii was a freshwater species while C. meneghiniana, C. quillensis, and C. poyeka thrived in saline conditions. [ABSTRACT FROM AUTHOR]

This paper presents the results of the analysis of a late Acheulean horizon from the EDAR 135 site, which was discovered in the Eastern Desert, Sudan, in an area heavily transformed by modern mining activity. A lithic assemblage was discovered there, within a layer of gravel sediments formed by a paleostream in a humid period of the Middle Pleistocene. This layer is OSL dated between 220 ± 12 and 145 ± 20 ka (MIS 7a/6). These dates indicate that the assemblage could be the youngest trace of the Acheulean in northeastern Africa. Technological analysis of the lithics reveals different core reduction strategies, including not only ad hoc ones based on multiplatform cores, but also discoidal and prepared cores. The use of prepared core reduction methods has already been confirmed at other Late Acheulean sites in Africa and the Middle East. Microwear traces observed on lithic artifacts could relate to on-site butchering activities. [ABSTRACT FROM AUTHOR]

Gabal Abu Garadi area is covered by metasediments, alkali feldspar granites and stream sediments. Geochemically, silicification, desilicification, sericitisation, fluoritisation and Na-metasomatism are the main alteration features of alkali feldspar granites. The activity concentration of 238U in alkali feldspar granites ranged between 1.7 ± 0.1 Bq g−1 and 3.9 ± 0.3 Bq g−1; between 1.7 ± 0.2 Bq g−1 and 9.4 ± 1.4 Bq g−1 for 234U and between 0.012 ± 0.0002 Bq g−1 and 0.09 ± 0.0001 Bq g−1 for 235U. The activity concentration of 228Th ranges between 1.3 ± 0.1 Bq g−1 and 3.6 ± 0.8 Bq g−1; between 1.5 ± 0.2 Bq g−1 and 2.7 ± 0.7 Bq g−1 for 230Th and between 1.8 ± 0.3 Bq g−1 and 4.1 ± 0.4 Bq g−1 for 232Th. The variability in Chemical Index of Alteration (CIA) with U, Th, 230Th/238U and 230Th/234U for the studied altered granite indicates that U and Th concentrations increased with increasing alteration especially in the silicified and desilicified samples. Changes in U, Th, 230Th/238U and 230Th/234U suggest the role of alteration processes in uranium and thorium mobilisation though thorium is geochemically less mobile or immobile. Thorium mobilisation could be controlled by adsorption in the alteration products of Abu Garadi granites such as clay minerals, manganese and iron oxides. In contrast, 230Th/238U and230Th/234U decreased with increasing CIA values suggesting uranium accumulation. 234U/238U ratios were in equilibrium in most samples; this might suggest the effect of severe chemical weathering or alteration processes that leads to the leachability of the two radionuclides (234U, 238U) with the same ratio probably during kaolinisation processes. In contrast, 230Th/238U and230Th/234U>1 were in disequilibrium, suggesting the changes in the physicochemical conditions accompanying the different alteration processes. [ABSTRACT FROM AUTHOR]

Milk has been known for its nutritional properties for centuries and is often the staple of the diet in many countries. Therefore, monitoring of milk composition seems to be a relevant task as it was the purpose of this study to compare levels of 210Po and 210Pb in several Polish voivodeships. The methodology was based on mineralization, loss on an inorganic matrix and concentration measurement on an alpha spectrometer. The concentrations of 210Po and 210Pb in collected milk samples were measured using alpha spectrometry and calculations, respectively. The results showed that the lowest concentration of 210Po is 2.8 ± 0.2 mBq l−1 and the highest is 56.3 ± 0.7 mBq l−1 while the 210Pb concentrations are in the range from 2.8 ± 0.2 to 44.0 ± 1.7 mBq l−1. The associated annual effective doses for adults jmrange from 3.5 ± 0.1 to 11.0 ± 0.2 µSv a−1 for 210Po and from 2.0 ± 0.1 to 5.0 ± 0.1 µSv a−1 for 210Pb. The lowest doses were noticed in Kuyavian-Pomeranian Voivodeship and the highest values were found in Lesser Poland Voivodeship. The results show that the annual effective dose in individual provinces is not dangerous to health. However, there are significant differences between highly and lowly industrialized voivodeships. [ABSTRACT FROM AUTHOR]

Stable isotope techniques can be used to assess nutrient acquisition and allocation strategies used to produce offspring. Before stable isotope techniques can be employed, researchers need reliable isotope discrimination values. In this context, isotope discrimination compares the difference in the isotope ratio between the maternal–offspring tissue that occurs during nutrient transfer prior to egg laying. Currently, isotope discrimination values are unknown between the maternal blood constituents – that reflect different temporal scales of integration – and downy feathers of their offspring. In this study, we experimentally derive isotope discrimination relationships between maternal diet–blood constituents for egg laying, and between maternal blood constituents–down feathers of offspring in an experiment with 3 types of domesticated gallinaceous birds raised on known diets. Our experiment is the first to report isotope discrimination values for maternal blood constituents–down of offspring in avian taxa and provides a new sampling technique that is less invasive than previously available as collecting down does not require sampling viable eggs or individuals. Future researchers can use these results to assist in identifying nutrient sources used by adult birds to produce young. [ABSTRACT FROM AUTHOR]