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The Kaladawan iron deposit is located in the North Altyn Tagh and exhibits occurrences of iron ore bodies at the contact zone between Ordovician magmatic rocks (basalts, rhyolite, and granodiorite) and marble. However, controversy persists regarding the genetic classification and metallogenic mechanism of this deposit. Through a field investigation, single mineral in situ geochemical analysis, whole-rock geochemical analysis, and Fe isotope determination, the following conclusions are made: (1) Ti-(Ni/Cr) and (V/Ti)-Fe diagrams indicate that the magnetite from all studied rocks underwent hydrothermal metasomatism, while (Ni/(Cr + Mn))-(Ti + V) and (Ca + Al + Mn)-(Ti + V) diagrams suggest a skarn origin for these magnetites. Therefore, it can be inferred that the Kaladawan iron deposit is skarn-type. (2) The iron ore exhibits similar rare-earth-element characteristics to the altered basalt. Additionally, the altered basalts (δ56Fe = 0.024~0.100‰) are more enriched in light Fe isotopes than the unaltered basalts (δ56Fe = 0.129~0.197‰) at the same location, indicating that the ore-forming materials of the Kaladawan iron ore are mainly derived from basaltic rocks. (3) According to the law of mass conservation and the intermediate Fe isotopic composition of the iron ore between the granodiorite and basalt, the hydrothermal fluid for the formation of iron ores was inferred to be derived from the late intrusive granodiorite. [ABSTRACT FROM AUTHOR]

Whether environmental responsibility can promote corporate performance has always been a focus of debate in theory and practice. We address the dispute regarding the effect of environmental responsibility by focusing on small and medium‐sized enterprises (SMEs) in China. Furthermore, based on team faultline theory, we argue that top management team (TMT) faultlines and bankruptcy threat combine to affect the relationship between environmental responsibility and long‐term performance in SMEs. Using data from 410 Chinese companies listed on the Growth Enterprise Market (GEM) during 2011–2020, we find that SMEs that engage in more environmental responsibility tend to have worse long‐term performance. Additionally, this relationship varies depending on the conditions of TMT composition (i.e., faultlines) and situation (i.e., bankruptcy threat). Specifically, when the bankruptcy threat is high, TMT faultlines negatively affect the relationship between environmental responsibility and long‐term firm performance. However, TMT faultlines positively affect this relationship when the bankruptcy threat is low. This paper sheds new light on corporate environmental responsibility by adopting a theoretical perspective of TMT faultlines and identifying the specific situations in which TMT faultlines act. [ABSTRACT FROM AUTHOR]

Two types of retrograded eclogite (phengite‐bearing eclogite and garnet pyroxenite) within eclogite‐facies granitic gneisses are reported for the first time from the Younusisayi area of the South Altyn high to ultrahigh pressure (HP–UHP) metamorphic belt. These eclogites were studied using petrology, mineral chemistry, phase equilibrium modelling, and geochronology. The phengite‐bearing eclogite records five stages of metamorphism: (1) early prograde (Grt + Cpx + Amp + Rt + Qz) at conditions of P = 11.50–17.5 kbar, T = 665–740°C; (2) peak eclogite‐facies (Grt + Omp + Ph + Rt + Qz) at conditions of P > 24.2 kbar, T = 710–1000°C; (3) overprinting during retrograde transition to HP granulite‐facies conditions (Grt + Cpx ± Kfs + Pl + Rt + Qz) at P = 12.1–16.9 kbar and T = 760–890°C; (4) retrogression at granulite‐facies conditions (Grt + Cpx + Amp + Pl + Ilm + Qz) of P = 9.1–11.4 kbar, T = 730–840°C; and (5) amphibolite‐facies metamorphism (Amp + Pl + Ilm + Qz) during cooling and decompression. The garnet pyroxenite records four stages of metamorphism: (1) eclogite‐facies at conditions of P > 23.2 kbar, T = 775–965°C; (2) HP granulite‐facies conditions of P = 13.2–17.8 kbar and T = 836–912°C; (3) granulite‐facies conditions of P = 8.6–9.7 kbar, T = 739–783°C; and (4) amphibolite‐facies metamorphism. Zircon U–Pb dating and trace element analysis constrain eclogite‐facies metamorphism to c. 500 Ma, consistent with the age of the surrounding eclogite‐facies granitic gneiss (497.8 ± 2.7 Ma). Retrograde metamorphism ages of c. 460 Ma are interpreted as recording zircon growth after granulite‐facies metamorphism. The P–T–t path defines the integrated process of deep subduction and multistage exhumation and places constraints on the early Palaeozoic geodynamics of the South Altyn belt. Well‐preserved major and trace element zoning of garnets in the Ph‐bearing eclogites lacks evidence of significant thermal diffusion and may record garnet growth during deep subduction, immediately followed by very rapid exhumation. [ABSTRACT FROM AUTHOR]

A ring-width series was developed from Dahurian larch (Larix gmelinii) in the northeastern forest area of Inner Mongolia, China. By analyzing the relationships between tree-ring data and climate records, an August–September mean maximum temperature (T89) series during 1845 and 2012 was reconstructed based on a simple linear regression equation. This reconstructed series explained 40.9% variance of the observed temperature from 1959 to 2012. The reconstructed T89 series was consistent with the historical disaster events caused by extreme climate (e.g., flood, frost disaster, and cold damage). Besides, the temperature comparisons showed that the year in which the warm months (April–September) in northeast China began to warm up has latitude differences. It started with a gradual delay from north to south, starting 1980 in the south region, after 1950 AD in the central region and after 1940 in the north region. Our study can enrich high-resolution temperature series in Northeast China and help clarify the characteristic of recent warming in northeast China. [ABSTRACT FROM AUTHOR]

Retrograde eclogite and garnet amphibolite of the Lüliangshan unit of the Shenglikou area, North Qaidam, were studied with emphasis on rutile and titanite. A special focus is on the formation of rutile and its corona of titanite (Ttn1) in retrograde eclogite and on coarse-grained titanite (Ttn2) from the garnet amphibolite. Using zirconium (Zr)-in-rutile and Zr-in-titanite thermometers, the temperatures estimated for the formation of an early generation of rutile are 823–884 °C at 2.5–2.8 GPa, while 812–894 °C at 1.3–1.5 GPa are derived for the formation of coronitic Ttn1 in the retrograde eclogite. Therefore, isothermal decompression must have occurred during exhumation, which also has triggered the partial melting of the retrograde eclogite. Ttn2 of the garnet amphibolite has high REE contents and high Th/U ratios, indicating that it is newly grown from a Ti, Ca, and LREE enriched anatectic melt derived from the partial melting of retrograde eclogite. LA-ICP MS U-Pb dating yields a lower intercept age of 423±4 Ma for Ttn2, which is consistent with the granulite-facies metamorphic age of the retrograde eclogite. Moreover, a temperature of 781–823 °C at 1.0–1.2 GPa is obtained for Ttn2, which fits the P-T conditions of the HP granulite-facies metamorphic stage (P=1.07–1.24 GPa and T=774–814 °C), and documents that the crystallization of the melt occurred at the granulite-facies stage at 423 Ma. The high amount of REE of the garnet amphibolite is a consequence of the formation of Ttn2 from the melt. The contents and ratios of Zr and Hf in rutile and Ttn2 differ from those in the garnet amphibolite, and the whole rock Zr/Hf ratios of retrograde eclogite and garnet amphibolite are both higher than the respective ratios in rutile and Ttn2, suggesting that rutile and titanite cannot be the major carriers of Zr and Hf accounting for the high whole rock Zr/Hf ratios. [ABSTRACT FROM AUTHOR]

The kyanite-bearing garnet pelitic gneiss from the Jianggalesayi area in southern Altyn Tagh high pressure/ultra-high pressure belt was proved to have been experienced UHP metamorphism (>12 GPa) by the discovery of kyanite and spinel exsolution microstructure in quartz (precursor stishovite). In this study, three stages of retrograded metamorphism (M2–M4) after the UHP metamorphism (M1) were identified for the UHP pelitic gneiss. The HP granulite-facies stage (M2) was characterized by the mineral assemblage of garnet+kyanite+K-feldspar+rutile+quartz±ilmenite, recording the P-T condition of >1.12 GPa and ≈850–930 ºC. The granulite-facies stage (M3) was represented by the mineral assemblage of garnet rim+K-feldspar+sillimanite (Sill1)+biotite (Bt1)+plagioclase (Pl1)+ilmenite+quartz, and confined under P-T conditions of 0.5–0.8 GPa and ≈770–795 ºC. The late cooling stage M4 was accompanied by the appearance of fine-grained Pl2, Sill2 and Bt2 in the matrix, and the P-T conditions were 0.4–0.6 GPa and <675 ºC. A clockwised P-T path was obtained for the pelitic gneiss in the P-T pseudosection, which showed a deep subduction/collision processes with subsequent exhumation and cooling. Combined with the corresponding multistage metamorphic assemblages, the age dating results implied that the zircons from the gneiss have integrated the recording peak metamorphic (M1, 484±3 Ma) and retrograded metamorphic ages (M2 to M3, 450±2 Ma). There was about 32 Ma interval during the first exhumation from the upper mantle depth (>350 km) to the lower crust depth (≈40–20 km), resulting in an average exhumation rate of 9.11–9.70 mm/yr. In the southern Altyn Tagh region, the HP and UHP rocks from different areas had identical peak metamorphic ages. Therefore, contemporary UHP and HP rocks with different metamorphic evolutions were recognized coexisting in the same orogenic belt, which can be interpreted by the model of subduction channel. The continental crustal were subducted to different depths along the direction of the subduction channels at ≈500 Ma, suffered different grade metamorphism, and then returned to the surface along the subduction channel. [ABSTRACT FROM AUTHOR]

The late cornified envelope (LCE) gene cluster is located on chromosome 1q21, including LCE1-LCE6. Several single nucleotide polymorphisms (SNPs) in the LCE cluster were associated with susceptibility to psoriasis in Chinese population. However, there is no report on the relationship in ethnic minority areas in China. This study aimed to investigate the association between the gene polymorphisms of LCE1B, LCE1C, LCE3A, LCE3D and psoriasis vulgaris among Mongolians from Inner Mongolia. Totally, 305 Mongolians with psoriasis vulgaris (PsV) and 383 healthy controls were enrolled in the study from 2006 to 2015. 7 SNPs including rs6701216, rs4112788, rs12023196, rs512208, rs4845454, rs4085613 and rs1886734, were selected for genotyping with ligase detection reaction (LDR). Statistical analysis was performed for comparisons of allele frequencies and genotype frequencies between the patient group and the control group. In this study, excluding rs4085613 and rs1886734, differences were detected in the allele frequencies of other 5 SNPs between the patients and controls. Genotype analysis showed that under the recessive inheritance model, the genotype frequencies of rs4845454, rs4112788 differed between the patients and controls (all p < 0.00 5).Under the dominant and the recessive model, the genotype frequencies of rs6701216, rs12023196 and rs512208 significantly differed between the patients and controls. The LD analysis showed that strong LD existed between rs6701216 and rs12023196, rs4845454 and rs4085613, rs4845454 and rs1886734, and rs4085613 and rs1886734. The SNPs rs6701216, rs4112788, rs12023196, rs512208 and rs4845454 in the LCE gene were associated with psoriasis vulgaris among Mongolians from Inner Mongolia. [ABSTRACT FROM AUTHOR]

Four episodes of granitic rocks at 517, 501-496, 462-451, and 426-385 Ma occurred in the South Altyn subduction-collision complex. The first episode of granite emplacement predates the formation of the ophiolite type mafic rock (≥500 Ma), and the three subsequent episodes can be temporally correlated to high-pressure (HP) to ultrahigh-pressure (UHP) metamorphism at ca. 500 Ma, retrograde granulite-facies metamorphism at ca. 450 Ma, and amphibolite-facies metamorphism at ca. 420 Ma, respectively. A comprehensive study of these granitic rocks, along with the regional geological background, mafic-ultramafic rocks, and HP-UHP metamorphism, indicates that the four episodes of granitic magmatism are sequentially derived from the partial melting of the earlier subducted oceanic crust at 517 Ma, the thickened continental crust due to continental subduction at ca. 500 Ma, the mid-upper crust in response to slab breakoff at ca. 450 Ma, and the tectonic transition from contraction to extension at ca. 420 Ma. The formation age of 517 Ma for oceanic adakite provides a direct constraint on the time of the oceanic subduction in South Altyn. In addition, there is a ca. 10 Myr interval between the oceanic subduction to the continental deep subduction, suggesting that the Early Paleozoic tectonic evolution might have been a successive process in South Altyn. The four episodes of formation of granitic rocks, mafic-ultramafic rocks, and HP-UHP metamorphic rocks have fully recorded the tectonic evolution, beginning with the oceanic subduction, followed by continental subduction, and later exhumation during the Early Paleozoic in South Altyn. [ABSTRACT FROM AUTHOR]

This study focuses on the determination of the age and provenance of a Precambrian unit on the southwestern margin of the Tarim craton, collectively known as the Ailiankate (埃连卡特) Group and Sailajiazitage (塞拉加兹塔格) Group, which were previously referred to as Paleoproterozoic-Mesoproterozoic. Zircon U-Pb LA-ICP-MS dating of chlorite quartz schist and tuff that form the Ailiankate Group and Sailajiazitage Group have yielded age peaks at 780 and 787 Ma, respectively. These data indicate that the Ailiankate and Sailajiazitage groups are Neoproterozoic succession deposited at ca. 740-790 Ma. Those strata are temporally equivalent and are likely parts of a single wide spread succession and reflect a rifting process related to the break-up of the Rodinia supercontinent. In situ zircon Hf isotopic data from Sailajiazitage Group show that older zircons (∼1 994 Ma) have crustal model ages of 2 272-2 784 Ma, suggesting an ancient crustal growth and reworking. The ∼787 Ma zircons have ∼2 000 Ma crustal model ages, suggesting derivations from recycled Paleoproterozoic material. [ABSTRACT FROM AUTHOR]

Tree growth in mountain ecosystems is affected by complex environments, and its relationship with climatic and environmental factors varying with elevation. In order to examine the spatial variation and temporal stability of the growth/climate relationship of Betula platyphylla (BP), the dendrochronological method was used to analyze the radial growth/climate relationship between 1946 and 2016 of the BP trees along an altitudinal gradient in the Changbai Mountain of northeast China. Our results showed that the mean sensitivity of BP was higher than that of other species studied in Changbai Mountain. The growth/climate relationship of BP trees varies with altitude, and this conclusion has reached a consensus from the study of tree growth response to climate change. More specifically, at low altitudes (550–995 m a.s.l.), the radial growth of BP is mainly affected by spring precipitation and temperature in May and October of the current year. However, at high-altitude areas (1210–1425 m a.s.l.), it is mainly affected by the temperature in September of the previous year and May of the current year. Furthermore, the growth/climate relationship of BP trees showed temporal instability. After 1970, the rise in temperature inhibited the growth of BP at low altitudes and promoted the growth of BP trees at high altitudes. In the context of continued warming in the future, the white birch stands in Changbai Mountain will move to higher altitudes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magmatism formed during the initial stage (ca. 480Ma) and advanced stage (ca. 450Ma) of exhumation of subducted continental crust have been recognized in South Altyn western China. • Two stages of magmatism exhibits evidence for the partial melting of subducted continental crust during differential exhumation process of South Altyn in Palaeozoic. The early Palaeozoic continental subduction–collisional belt in South Altyn (SA) western China distributes a large amount of (ultra)-high-pressure ((U)HP) metamorphic and granitic rocks associated with subduction, collision, and exhumation. In this study, four granitic rocks were collected from Bashenwake located in eastern SA. The ages of the garnet-bearing alkali-feldspar granite (GAFG), garnet-bearing granitic gneiss (GGG), alkali-feldspar granite (AFG), and syenogranite (SG) are 458.0 ± 4.1, 483.0 ± 4.1, 450.0 ± 2.4, and 482.0 ± 4.9 Ma, respectively. Whole-rock major and trace elements and Sr–Nd–Pb isotope, and zircon Hf isotope compositions for all samples exhibit characteristics of a continental crustal source. Based on partial melting modeling, the source temperature of the GGG, GAFG, AFG and SG was concluded as 750–780 °C, 730–760 °C, 730–770 °C and ca. 800 °C, respectively. The source pressure was estimated as ca. 0.8 GPa for the GGG, GAFG and AFG, and ca. 1.2 GPa for SG. Combined with studies on (U)HP metamorphic rocks in SA, this study reveals that GGG is formed by metamorphism while SG is formed from partial melting of upper crustal rocks heated by upwelling mantle during the initial stage of exhumation (ca. 480 Ma) of subducted continental crust in SA. During further stage of exhumation of the subducted continental crust at ca. 450 Ma, the GAFG and AFG were formed from partial melting of GGG as a result of decreased pressure and further mantle upwelling. Consequently, the exhumation age of subducted continental crust in eastern SA is ca. 30 Myr earlier than that in western SA. Thus, the geochronology and petrogenesis of four granitic samples in this study exhibit one of very few evidence for partial melting of subducted continental crust during the exhumation and also provide magmatism exhibits evidence for the differential exhumation model of eastern SA in Palaeozoic. [ABSTRACT FROM AUTHOR]

Background: Stroke is a serious disease that threatens human health both in China and worldwide. Identifying and establishing its risk factors are prerequisites for intervention and evaluation of prognosis. Over the years, risk factors, such as age, diabetes, and hypertension, have gradually been established. However, at present, there is no consensus on the influence of sex on the prognosis of ischaemic stroke., Aims: The aims of our research was to analyse the correlation between sex and poststroke prognosis based on the results of the Third China National Stroke Registry [CNSR-III], as well as the influence of other risk factors that may be confounded by sex on ischaemic stroke and potential interventions., Methods: The CNSR-III recruited 14146 acute ischaemic stroke [AIS] patients between 2015 and 2018. Our study included 13,972 patients who had complete follow-up information. This research analysed basic information, socioeconomic status, lifestyle habits, medical history, and poststroke prognosis., Results: There was a conspicuous relationship between sex and functional prognosis, stroke recurrence and all-cause death due to ischemic stroke in univariate analysis. Male stroke patients had a better prognosis than female patients. In multivariate analysis, we found that age, atrial fibrillation [AF], diabetes, hypertension and the severity of stroke had adverse effects on ischemic stroke prognosis. After adjustment for other risk factors, the functional prognosis of female patients at 3 months was worse than that of male patients [odds ratio [OR] 1.16, 95% confidence interval [CI], 1.025- 1.314]. Sex had a nonsignificant association with stroke recurrence at 3 months [hazard ratio [HR] 1.141, 95% CI, 0.975-1.336]. Furthermore, compared to male patients, female stroke patients had a lower cumulative death rate at 12 months [HR 0.777, 95% CI, 0.628-0.963]., Conclusion: Our study identified sex differences in stroke-related disability, recurrence, and death and attempted to explain the causes of these differences. Our study clearly showed that a large proportion of this difference could be attributed to age, socioeconomic factors, lifestyle habits, and medical history, confounded by sex differences rather than sex per se., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)