bluuebunny/crossref_metadata_2025_split huggingface dataset:
Components and structures of the eastern Tethyan Himalayan Sequence in SW China: Not a passive margin shelf but a mélange accretionary prism
Authors: Ao Songjian , Xiao Wenjiao , Windley Brian F. , Zhang Ji'en , Zhang Zhiyong , Yang Lei 
Published: January 2018

The Tethyan Himalaya Sequence between the Yarlung‐Zangbo Suture and South Tibetan Detachment is a fundamental component of the Himalayan orogenic belt, traditionally considered to belong to the passive continental margin of India. However, the eastern Tethyan Himalaya Sequence is poorly understood, compared with that in the central and western Himalaya. To improve general understanding, we undertook north‐south geological‐structural profiles across all the litho‐tectonic units of the eastern Tethyan Himalaya Sequence and produced new isotopic‐geochemical data from all units, to constrain their mode of occurrence, structure, tectonic setting, and time of formation. The whole Tethyan Himalaya Sequence consists of a thrust‐imbricated mélange that contains blocks of ophiolites (such as Lang County, Yumen, and Lhunze), oceanic islands (e.g., Comei) with ocean island basalts‐type basalts, mafic greenschists, limestone olistoliths, and cherts in a turbiditic matrix of greywackes, siltstones, and slates in south‐directed thrust slices. Our findings suggest that the eastern Tethyan Himalaya Sequence represents the evolution of an accretionary prism, rather than a passive margin of the Indian Plate. The prism was created during northward subduction of Neo‐Tethys between ~130 and ~50 Ma. These data allow us to produce a new tectonic model for the structural development of the eastern Himalayan orogenic belt in relation to the India‐Asia collision.
Petrology and mineralogy of pumice from the Iheya North Knoll, Okinawa Trough: Implications for the differentiation of crystal‐poor and volatile‐rich melts in the magma chamber
Authors: Zhang Yuxiang , Zeng Zhigang , Yin Xuebo , Qi Haiyan , Chen Shuai , Wang Xiaoyuan , Shu Yunchao , Chen Zuxing 
Published: January 2018

The Iheya North Knoll is a submarine hill that is covered with pumice in the Okinawa Trough. The petrology and mineralogy of the crystal‐poor rhyolitic pumice collected from two sampling sites (T3 and T6) on the knoll were analysed in this article. The T6 pumice, which contains some mafic minerals (e.g., clinopyroxene, orthopyroxene), is slightly more crystal‐rich (<5 vol.%) than the T3 pumice (<2 vol.%). However, both types of pumice are high‐potassium rhyolites with similar Nd isotopic ratios and rare earth element patterns, as well as similar glass compositions, which indicates that they may fall along a line of descent of comagmatic evolution. The T6 pumice contains some xenomorphic clinopyroxenes that are not in equilibrium with their whole‐rock composition, which suggests that the crystal‐poor melt was extracted from a more mafic source. The T3 pumice features a flow structure, and its matrix glass records higher Cl concentrations and a lower total mass than the T6 pumice, which implies that the T3 melt has a higher volatile content and lower viscosity. The distinct petrographic characteristics but similar matrix glass compositions of the T3 and T6 pumice suggest that the extracted melt was physically differentiated during ascent, with the more crystal‐poor and volatile‐rich T3 melt reaching a higher lever in the magma chamber. Meanwhile, simulation calculations indicate that the melt experienced near‐adiabatic decompression‐driven chemical differentiation, which led to the growth of sodium‐rich plagioclase but not quartz in the pumice.
Provenance discrimination between Atasta and Alvarado beach sands, western Gulf of Mexico, Mexico: Constraints from detrital zircon chemistry and U–Pb geochronology
Authors: Armstrong‐Altrin John S. , Ramos‐Vázquez Mayla A. , Zavala‐León Ana C. , Montiel‐García Patricia C. 
Published: January 2018

The bulk sand samples and detrital zircons collected from the Atasta and Alvarado beach areas in the southwestern Gulf of Mexico have been analysed for geochemistry and U–Pb ages to constrain their provenance. The index of chemical maturity and SiO2/Al2O3 ratio of the Atasta and Alvarado beach sands indicated low compositional maturity. The chondrite‐normalized REE patterns and Eu anomalies of the Atasta and Alvarado beach sands suggested that the sands were derived from felsic and intermediate igneous rock types, respectively. A wide range in Th and U contents of the Atasta (~1.0–884 ppm and ~39–883 ppm, respectively) and Alvarado (~13–2,641 ppm and ~21–2,457 ppm, respectively) zircons likely indicates that the detrital zircon populations consist of zircons derived from multiple sources. The total rare earth element (ΣREE) content in the Atasta and Alvarado zircons ranges from ~151 to 2,088 ppm and ~154 to 3,580 ppm, respectively. The chondrite‐normalized REE patterns of zircons from the two beach areas show slightly depleted light REE (LREE) and enriched heavy REE (HREE), as well as positive Ce and negative Eu anomalies. A few zircons of Alvarado beach lack a Ce positive anomaly but exhibit a distinct Eu anomaly. The differences in REE patterns among zircons between the two beach areas revealed the variations in the type of source terranes, which supplied zircons to the beach areas. The detrital zircon age distribution for the Atasta beach is homogeneous, showing a prominent Proterozoic peak (~596–2,461 Ma; number of samples n = 62) with few Cenozoic (~10.43–65.2 Ma; n = 4) and Palaeozoic (~380–468 Ma; n = 5) zircons. The zircon U–Pb ages of Alvarado beach revealed Cenozoic (~0.25–63.9 Ma; n = 65), Mesozoic (~67.9–181.2 Ma), Palaeozoic (~252–297 Ma), and Proterozoic (~589–1,501 Ma) age clusters with predominant Cenozoic zircons. The comparison of zircon REE chemistry and geochronological data of this study with published data suggests that the source terranes, which supplied zircons to the Atasta beach, were the Chiapas Massif and Oaxacan complexes, whereas the zircons in the Alvarado beach were derived from the nearby Mexican Volcanic Belt and Eastern Alkaline Province. The provenance variation between the two beach areas was also revealed by the dissimilarities in zircon age clusters.
Geological characteristics, metallogenesis, and tectonic setting of porphyry–skarn Cu deposits in East Kunlun Orogen
Authors: Wang Hui , Feng Chengyou , Li Rongxi , Li Daxin 
Published: January 2018

The East Kunlun Orogen (EKO), as the west segment of the Central China Orogen, is the most important Triassic polymetallic metallogenic belt in China. In this paper, we summarize the geological characteristics (stratigraphy, structure, ore‐related plutons, wall rock alteration, and orebodies), ore‐forming fluids and materials, geochronology, and petro‐geochemistry of the representative porphyry–skarn Cu–polymetallic deposits, including the Saishitang, Hutouya, and Kaerqueka deposits in the EKO. The porphyry–skarn Cu deposits in the EKO are mainly distributed in tectonic units of the Qimantagh Belt and the Elashan Belt. Among them, the skarn Cu deposits provide the majority of Cu resources, which mainly occur in the contact zone between the Triassic granitoids and the volcanic–sedimentary rocks (e.g., the Ordovician–Silurian Tanjianshan Group and the Early to Middle Triassic Hongshuichuan Group), and the skarn and orebodies are mainly controlled by interlayer–gliding structures. Ore‐forming fluids of the porphyry Cu deposits are magmatic mixed with meteoric water, whereas the fluids of skarn Cu deposits are mainly of magmatic origin. The higher δ18O (>10‰) of garnet and pyroxene in prograde skarn and wide range of sulphur isotopic compositions (δ34S values from −8.9‰ to 11.0‰) suggest that ore‐forming materials of skarn Cu deposits were partially derived from the country rocks. Based on detailed field investigations, we identified four Cu mineralization types, including veinlet–disseminated Cu (Mo, Au) mineralization occurring within the intrusions, proximal skarn Cu (Fe, Pb, Zn, Au) mineralization, distal skarn Cu mineralization, and distal skarn Pb–Zn (Cu) mineralization. The porphyry–skarn Cu deposits are associated with magmatism that occurred mainly during 235–218 Ma. The ore‐related granitoids are mostly calc‐alkaline I‐type granites, derived from partial melting of the Precambrian basement rocks with various degrees of involvement of mantle components. Combined with the regional tectonic evolution, we conclude that the Cu mineralization in the EKO began with the closure of A'nyemaqen Ocean (~238 Ma) and subsequently culminated in a postcollisional setting (~225 Ma).
Implications of U–Pb detrital zircon geochronology analysis for the depositional age, provenance, and tectonic setting of continental Mesozoic formations in the East Malaya Terrane, Peninsular Malaysia
Authors: Basori Mohd Basril Iswadi , Leman Mohd Shafeea , Zaw Khin , Meffre Sebastien , Large Ross Raymond , Mohamed Kamal Roslan , Makoundi Charles , Mohd Zin Mazlinfalina 
Published: January 2018

Mesozoic strata in the East Malaya Terrane of Peninsular Malaysia record a long but poorly constrained history of basin evolution. In this study, we report LA‐ICP‐MS U–Pb geochronology analyses of detrital zircons in the continental Mesozoic sequences from the Bertangga and Gerek formations of Peninsular Malaysia, with the aim to constrain the depositional ages and provenances of the continental Mesozoic strata as well as the Mesozoic tectonic evolution of the East Malaya Terrane. The Bertangga Formation yields populations of U–Pb zircon ages of Jurassic (139 to 194 Ma), Permo−Triassic (226 to 274 Ma), Ordovician−Devonian (372 to 459 Ma), Neoproterozoic (631 to 876 Ma), and Mesoproterozoic−Palaeoproterozoic (1,448 to 2,629 Ma). In contrast, the Gerek Formation yields significant Carboniferous grains, but with an approximate zircon age range relative to the Bertangga Formation. The new data indicate a maximum Late Jurassic depositional age for the previously undated Bertangga Formation. Similarly, young zircon grain ages in the Gerek Formation also indicate a maximum Late Jurassic depositional age. Collectively, these results on detrital zircons correlate well with a regional tectonic uplift and erosion to a tectonic stability of the East Malaya Terrane basin during the Mesozoic.
Late Cretaceous tectono–magmatic event in Songliao Basin, NE China: New insights from mafic dyke geochronology and geochemistry analysis
Authors: Cheng Yinhang , Li Ying , Wang Shaoyi , Li Yanfeng , Ao Cong , Li Jianguo , Sun Lixin , Li Hongliang , Zhang Tianfu 
Published: January 2018

The ages and source of Late Cretaceous mafic dolerite dykes of the Songliao Basin were determined using geochronological, geochemical, zircon Hf, whole‐rock Sr–Nd isotopic, and zircon fission tract. The results show that (a) petrographic data reveal doleritic, poikiloblastic textures, and amygdale structures of the dolerite dykes. (b) LA‐MC‐ICP‐MS U–Pb analysis of zircons yielded an age of 70.0 ± 3.0 Ma of one of these mafic dykes in agreement with the zircon fission track age (69–68 Ma) of host rocks within uncertainty, placing them within the Late Cretaceous. (c) Geochemical researches indicate that the dykes are classified as the alkaline and tholeiitic series according to their major elements and characterized by high Na2O (2.79–4.89 wt.%), TiO2 (1.63–2.71 wt.%), and low K2O (0.46–2.45 wt.%). And they have enrichment of incompatible elements (e.g., K, Ti, Rb, Ba, Th, U, Nb, Ta, and REEs), high Rb/Sr (0.026–0.066), LaN/YbN (3.83–15.93), near‐chondritic HREEs ([Gd/Yb]N = 1.78–3.37), low Sm/Nd (0.202–0.282) ratios, and with negligible Eu anomalies (Eu/Eu* = 0.98–1.06). The dykes contain relatively low amounts of radiogenic Sr, as shown by (87Sr/86Sr)i values (0.7037–0.7045), and have positive values of εNd(t) (3.66–5.40) and εHf (t) (2.66–7.45), suggesting that the mafic dykes have been derived from partial melting of the depleted lithospheric mantle and contaminated by crust in the source region and formed in back‐arc rift settings caused by the subduction of the Pacific Oceanic Plate. All the above indicate large‐scale extensional event in Songliao Basin NE China at about 70 Ma.
Near‐surface hydraulic conductivity of northern hemisphere glaciers
Authors: Stevens Ian T. , Irvine‐Fynn Tristram D.L. , Porter Philip R. , Cook Joseph M. , Edwards Arwyn , Smart Martin , Moorman Brian J. , Hodson Andy J. , Mitchell Andrew C. 
Published: January 2018

AbstractThe hydrology of near‐surface glacier ice remains a neglected aspect of glacier hydrology despite its role in modulating meltwater delivery to downstream environments. To elucidate the hydrological characteristics of this near‐surface glacial weathering crust, we describe the design and operation of a capacitance‐based piezometer that enables rapid, economical deployment across multiple sites and provides an accurate, high‐resolution record of near‐surface water‐level fluctuations. Piezometers were employed at 10 northern hemisphere glaciers, and through the application of standard bail–recharge techniques, we derive hydraulic conductivity (K) values from 0.003 to 3.519 m day−1, with a mean of 0.185 ± 0.019 m day−1. These results are comparable to those obtained in other discrete studies of glacier near‐surface ice, and for firn, and indicate that the weathering crust represents a hydrologically inefficient aquifer. Hydraulic conductivity correlated positively with water table height but negatively with altitude and cumulative short‐wave radiation since the last synoptic period of either negative air temperatures or turbulent energy flux dominance. The large range of K observed suggests complex interactions between meteorological influences and differences arising from variability in ice structure and crystallography. Our data demonstrate a greater complexity of near‐surface ice hydrology than hitherto appreciated and support the notion that the weathering crust can regulate the supraglacial discharge response to melt production. The conductivities reported here, coupled with typical supraglacial channel spacing, suggest that meltwater can be retained within the weathering crust for at least several days. Not only does this have implications for the accuracy of predictive meltwater run‐off models, but we also argue for biogeochemical processes and transfers that are strongly conditioned by water residence time and the efficacy of the cascade of sediments, impurities, microbes, and nutrients to downstream ecosystems. Because continued atmospheric warming will incur rising snowline elevations and glacier thinning, the supraglacial hydrological system may assume greater importance in many mountainous regions, and consequently, detailing weathering crust hydraulics represents a research priority because the flow path it represents remains poorly constrained.
Fingolimod targets cerebral endothelial activation to block leukocyte recruitment in the central nervous system
Authors: Zhao Yawei , Shi Dongyan , Cao Kelei , Wu Fengjiao , Zhu Xingxing , Wen Shuang , You Qiang , Zhang Keqi , Liu Lixin , Zhou Hong 
Published: January 2018

Abstract
Fingolimod (FTY720), an immunomodulator, is approved as an oral treatment for patients with relapsing forms of multiple sclerosis. Its effects are largely attributed to its mechanism of selectively retaining lymphocytes in the lymph nodes to reduce autoreactive T-cell recruitment in the CNS. In this study, we investigated the therapeutic effect of FTY720 on an animal model of CNS inflammation induced by intracerebral ventricle LPS injection. We found that FTY720 treatment significantly prevented LPS-induced neutrophil recruitment in the CNS by inhibiting leukocyte recruitment in cerebral microvessels. Furthermore, FTY720 also inhibited the expressions of adhesion molecules on the cerebral endothelium, but did not affect the expression levels of pro-inflammatory cytokines (TNF-α and IL-6) and chemokines (CXCL1 and CXCL2) in the CNS parenchyma. The inhibition of endothelial activation was accompanied by reduced phosphorylation of signaling molecules, including serine/threonine-specific protein kinase (Akt), STAT6, and nuclear factor-κB. This FTY720-attenuated inhibition of leukocyte recruitment and endothelial activation was reversed by blocking the functions of sphingosine kinase 2 or sphingosine-1-phosphate receptor 1. Our study demonstrated, for the first time, that FTY720 directly inhibits the phosphorylation of multiple signaling molecules in endothelial cells, thereby effectively blocking leukocyte recruitment in the CNS.
Protease activated-receptor 2 is necessary for neutrophil chemorepulsion induced by trypsin, tryptase, or dipeptidyl peptidase IV
Authors: White Michael J V , Chinea Luis E , Pilling Darrell , Gomer Richard H 
Published: January 2018

Abstract
Compared to neutrophil chemoattractants, relatively little is known about the mechanism neutrophils use to respond to chemorepellents. We previously found that the soluble extracellular protein dipeptidyl peptidase IV (DPPIV) is a neutrophil chemorepellent. In this report, we show that an inhibitor of the protease activated receptor 2 (PAR2) blocks DPPIV-induced human neutrophil chemorepulsion, and that PAR2 agonists such as trypsin, tryptase, 2f-LIGRL, SLIGKV, and AC55541 induce human neutrophil chemorepulsion. Several PAR2 agonists in turn block the ability of the chemoattractant fMLP to attract neutrophils. Compared to neutrophils from male and female C57BL/6 mice, neutrophils from male and female mice lacking PAR2 are insensitive to the chemorepulsive effects of DPPIV or PAR2 agonists. Acute respiratory distress syndrome (ARDS) involves an insult-mediated influx of neutrophils into the lungs. In a mouse model of ARDS, aspiration of PAR2 agonists starting 24 h after an insult reduce neutrophil numbers in the bronchoalveolar lavage (BAL) fluid, as well as the post-BAL lung tissue. Together, these results indicate that the PAR2 receptor mediates DPPIV-induced chemorepulsion, and that PAR2 agonists might be useful to induce neutrophil chemorepulsion.
Optimization of 18F‐syntheses using 19F‐reagents at tracer‐level concentrations and liquid chromatography/tandem mass spectrometry analysis: Improved synthesis of [18F]MDL100907
Authors: Zhang Xiang , Dunlow Ryan , Blackman Burchelle N. , Swenson Rolf E. 
Published: January 2018

Traditional radiosynthetic optimization faces the challenges of high radiation exposure, cost, and inability to perform serial reactions due to tracer decay. To accelerate tracer development, we have developed a strategy to simulate radioactive 18F‐syntheses by using tracer‐level (nanomolar) non‐radioactive 19F‐reagents and LC‐MS/MS analysis. The methodology was validated with fallypride synthesis under tracer‐level 19F‐conditions, which showed reproducible and comparable results with radiosynthesis, and proved the feasibility of this process. Using this approach, the synthesis of [18F]MDL100907 was optimized under 19F‐conditions with greatly improved yield. The best conditions were successfully transferred to radiosynthesis. A radiochemical yield of 19% to 22% was achieved with the radiochemical purity >99% and the molar activity 38.8 to 53.6 GBq/ μmol (n = 3). The tracer‐level 19F‐approach provides a high‐throughput and cost‐effective process to optimize radiosynthesis with reduced radiation exposure. This new method allows medicinal and synthetic chemists to optimize radiolabeling conditions without the need to use radioactivity.
Coupled impacts of ENSO AMO and PDO on temperature and precipitation in the Alabama–Coosa–Tallapoosa and Apalachicola–Chattahoochee–Flint river basins
Authors: Maleski Jerome J. , Martinez Christopher J. 
Published: January 2018

ABSTRACTLarge‐scale patterns of ocean surface temperature can influence weather across the globe and understanding their interaction with the local climate can improve seasonal forecasting of local temperature and precipitation. Here we focus on the combined interactions of the El Niño‐Southern Oscillation (ENSO), the Atlantic Multidecadal Oscillation (AMO) and the Pacific Decadal Oscillation (PDO) in the Alabama–Coosa–Tallapoosa (ACT) and Apalachicola–Chattahoochee–Flint (ACF) river basins of the southeastern United States. Nonparametric ranks‐sum tests of individual and coupled impacts of these teleconnections on the annual study area climate (1895–2009) found significant impacts. A positive AMO phase was associated with decreased precipitation and increased mean temperature while the negative AMO phase was associated with increased precipitation and decreased temperature. While an El Niño event generally increases regional precipitation, El Niño during a positive AMO or PDO phase resulted in precipitation below the long‐term average in our study area. Because of many instances of El Niño being shared between AMO and PDO phase, the effects of the PDO and AMO on El Niño could not be distinguished. La Niña was associated with negative precipitation and increased temperature. The effects of La Niña on the temperature and precipitation anomaly were significantly increased during positive AMO and PDO phases. The coupled impacts of the aforementioned teleconnections demonstrate the necessity of including the effects of the AMO and the PDO when using ENSO‐based forecasts. The significant shifts on the effects of teleconnections on area climate from AMO negative phase to AMO positive phase cast doubt on seasonal prediction for the study area based on the recent history (i.e. the use of the period 1950–2000 to predict seasonal climate since 2000).
Climatic and associated cryospheric, biospheric, and hydrological changes on the Tibetan Plateau: a review
Authors: Bibi Sadia , Wang Lei , Li Xiuping , Zhou Jing , Chen Deliang , Yao Tandong 
Published: January 2018

ABSTRACTWe review recent climate changes over the Tibetan Plateau (TP) and associated responses of cryospheric, biospheric, and hydrological variables. We focused on surface air temperature, precipitation, seasonal snow cover, mountain glaciers, permafrost, freshwater ice cover, lakes, streamflow, and biological system changes. TP is getting warmer and wetter, and air temperature has increased significantly, particularly since the 1980s. Most significant warming trends have occurred in the northern TP. Slight increases in precipitation have occurred over the entire TP with clear spatial variability. Intensification of surface air temperature is associated with variation in precipitation and decreases in snow cover depth, spatial extent, and persistence. Rising surface temperatures have caused recession of glaciers, permafrost thawing, and thickening of the active layers over the permafrost. Changing temperatures, precipitation, and other climate system components have also affected the TP biological system. In addition, elevation‐dependent changes in air temperature, wind speed, and summer precipitation have occurred in the TP and its surroundings in the past three decades. Before projecting multifaceted interactions and process responses to future climate change, further quantitative analysis and understanding of the change mechanisms is required.