117 research outputs found

    Geochemistry and geochronology of dolerite dykes from the Daba and Dongbo peridotite massifs, SW Tibet: Insights into the style of mantle melting at the onset of Neo-Tethyan subduction

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    This study reports compositional and whole-rock Sr-Nd isotope data as well as zircon U-Pb geochronological data on dolerite dikes from the Daba and Dongbo ultramafic massifs, southwest Yarlung-Zangbo Suture Zone (YZSZ), Tibet. The 120.6 \ub1 1.6 Ma dolerite dikes from the Daba peridotite exhibit normal mid-ocean ridge basalt (N-MORB)-type normalized mutli-element patterns [(La/Yb)N = 0.43-0.72] with noticeable negative Nb and Th anomalies. They have high initial 87Sr/8624 Sr ratios (87Sr/8625 Sr(i) = 0.70720-0.70788) and high \u3b5Nd(t) values (+7.4 to +7.9). The 125.4 \ub1 1.8 Ma dolerite intrusions within the Dongbo peridotite show N-MORB\u2012type trace element profiles [(La/Yb)N = 0.65-0.84] characterized by apparent negative anomalies in Nb and Th, and mild negative anomalies in Ti (\ub1 Y). They also have high 87Sr/8629 Sr(i) ratios (0.70611-0.70679) and elevated \u3b5Nd(t) values (+7.8 to +8.2). Semi-quantitative La/Yb vs. Dy/Yb modeling demonstrates that the parental magmas of the investigated dolerite dikes derived from more than 20% (cumulative) melting of a (broad) mantle source region that had a spinel-bearing N-MORB\u2013like lherzolitic composition. Our geochemical and isotopic data indicate that the composition of the inferred mantle source was influenced by minor input of subducted crustal material. The petrogenesis of the Daba and Dongbo massifs could be linked to upwelling of an asthenospheric source that caused continental rift and subsequent seafloor spreading, followed by subduction initiation adjacent to a passive margin during the early Cretaceous (~130-120 Ma). Our study provides a more detailed, and perhaps more elegant, hypothesis for the tectono-magmatic evolution of the southwestern YZSZ "ophiolitic" peridotites after their accretion beneath a Neo-Tethyan marginal basin

    5G PRS-Based Sensing: A Sensing Reference Signal Approach for Joint Sensing and Communication System

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    The emerging joint sensing and communication (JSC) technology is expected to support new applications and services, such as autonomous driving and extended reality (XR), in the future wireless communication systems. Pilot (or reference) signals in wireless communications usually have good passive detection performance, strong anti-noise capability and good auto-correlation characteristics, hence they bear the potential for applying in radar sensing. In this paper, we investigate how to apply the positioning reference signal (PRS) of the 5th generation (5G) mobile communications in radar sensing. This approach has the unique benefit of compatibility with the most advanced mobile communication system available so far. Thus, the PRS can be regarded as a sensing reference signal to simultaneously realize the functions of radar sensing, communication and positioning in a convenient manner. Firstly, we propose a PRS based radar sensing scheme and analyze its range and velocity estimation performance, based on which we propose a method that improves the accuracy of velocity estimation by using multiple frames. Furthermore, the Cramer-Rao lower bound (CRLB) of the range and velocity estimation for PRS based radar sensing and the CRLB of the range estimation for PRS based positioning are derived. Our analysis and simulation results demonstrate the feasibility and superiority of PRS over other pilot signals in radar sensing. Finally, some suggestions for the future 5G-Advanced and 6th generation (6G) frame structure design containing the sensing reference signal are derived based on our study

    Interaction between pollution and climate change augments ecological risk to a coastal ecosystem

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    Pollution and climate change are among the most challenging issues for countries with developing economies, but we know little about the ecological risks that result when these pressures occur together. We explored direct effects of, and interactions between, environmental pollution and climate change on ecosystem health in the Bohai Sea region of Northern China. We developed an integrated approach to assess ecological risks to this region under four scenarios of climate change. Although ecological risks to the system from pollution alone have been declining, interactions between pollution and climate change have enhanced ecological risks to this coastal/marine ecosystem. Our results suggest that current policies focused strictly on pollution control alone should be changed to take into account the interactive effects of climate change so as to better forecast and manage potential ecological risks

    Well Water Arsenic Exposure, Arsenic Induced Skin-Lesions and Self-Reported Morbidity in Inner Mongolia

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    Residents of the Bayingnormen region of Inner Mongolia have been exposed to arsenic-contaminated well water for over 20 years, but relatively few studies have investigated health effects in this region. We surveyed one village to document exposure to arsenic and assess the prevalence of arsenic-associated skin lesions and self-reported morbidity. Five-percent (632) of the 12,334 residents surveyed had skin lesions characteristics of arsenic exposure. Skin lesions were strongly associated with well water arsenic and there was an elevated prevalence among residents with water arsenic exposures as low as 5 μg/L-10 μg/L. The presence of skin lesions was also associated with self-reported cardiovascular disease

    Multiancestry Genome-Wide Association Study of Lipid Levels Incorporating Gene-Alcohol Interactions

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    A person's lipid profile is influenced by genetic variants and alcohol consumption, but the contribution of interactions between these exposures has not been studied. We therefore incorporated gene-alcohol interactions into a multiancestry genome-wide association study of levels of high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and triglycerides. We included 45 studies in stage 1 (genome-wide discovery) and 66 studies in stage 2 (focused follow-up), for a total of 394,584 individuals from 5 ancestry groups. Analyses covered the period July 2014-November 2017. Genetic main effects and interaction effects were jointly assessed by means of a 2-degrees-of-freedom (df) test, and a 1-df test was used to assess the interaction effects alone. Variants at 495 loci were at least suggestively associated (P <1 x 10(-6)) with lipid levels in stage 1 and were evaluated in stage 2, followed by combined analyses of stage 1 and stage 2. In the combined analysis of stages 1 and 2, a total of 147 independent loci were associated with lipid levels at P <5 x 10(-8) using 2-df tests, of which 18 were novel. No genome-wide-significant associations were found testing the interaction effect alone. The novel loci included several genes (proprotein convertase subtilisin/kexin type 5 (PCSK5), vascular endothelial growth factor B (VEGFB), and apolipoprotein B mRNA editing enzyme, catalytic polypeptide 1 (APOBEC1) complementation factor (A1CF)) that have a putative role in lipid metabolism on the basis of existing evidence from cellular and experimental models.Peer reviewe

    A multi-ancestry genome-wide study incorporating gene-smoking interactions identifies multiple new loci for pulse pressure and mean arterial pressure

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    Elevated blood pressure (BP), a leading cause of global morbidity and mortality, is influenced by both genetic and lifestyle factors. Cigarette smoking is one such lifestyle factor. Across five ancestries, we performed a genome-wide gene-smoking interaction study of mean arterial pressure (MAP) and pulse pressure (PP) in 129 913 individuals in stage 1 and follow-up analysis in 480 178 additional individuals in stage 2. We report here 136 loci significantly associated with MAP and/or PP. Of these, 61 were previously published through main-effect analysis of BP traits, 37 were recently reported by us for systolic BP and/or diastolic BP through gene-smoking interaction analysis and 38 were newly identified (P <5 x 10(-8), false discovery rate <0.05). We also identified nine new signals near known loci. Of the 136 loci, 8 showed significant interaction with smoking status. They include CSMD1 previously reported for insulin resistance and BP in the spontaneously hypertensive rats. Many of the 38 new loci show biologic plausibility for a role in BP regulation. SLC26A7 encodes a chloride/bicarbonate exchanger expressed in the renal outer medullary collecting duct. AVPR1A is widely expressed, including in vascular smooth muscle cells, kidney, myocardium and brain. FHAD1 is a long non-coding RNA overexpressed in heart failure. TMEM51 was associated with contractile function in cardiomyocytes. CASP9 plays a central role in cardiomyocyte apoptosis. Identified only in African ancestry were 30 novel loci. Our findings highlight the value of multi-ancestry investigations, particularly in studies of interaction with lifestyle factors, where genomic and lifestyle differences may contribute to novel findings.Peer reviewe

    Correlation of CD117 and DOG1 Expression with the Clinicopathological Features and Prognosis in Triple-negative Breast Cancer

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    ObjectiveTo investigate the expression of CD117 and DOG1 in triple-negative breast cancer (TNBC) and to explore their relationship with clinicopathologic features and prognosis.MethodsThe patients with TNBC in Peking Union Medical College Hospital from 2000 to 2011 were retrospectively collected and tissue microarrays were made. The expression of CD117 and DOG1 in tumor cells was detected by immunohistochemistry to analyze their relationship with the clinicopathological characteristics of the patients, such as age, tumor diameter, American Joint Committee on Cancer (AJCC) cancer stage, histological grade, P53, and Ki-67 proliferation index, and explore the effect of both on the survival of patients.ResultsA total of 185 TNBC patients meeting the inclusion and exclusion criteria were selected, of which 24 (12.97%) were CD117 positive and 22 (11.89%) were DOG1 positive, with a co-expression rate of 1.62%. Compared with CD117-negative patients, CD117-positive patients had higher Ki-67 proliferation index (87.50% vs. 67.70%, P=0.048), basal-like TNBC (95.83% vs. 74.53%, P=0.020), and P53 diffuse positive (33.33% vs. 13.66%, P=0.032).Compared with DOG1-negative patients, DOG1-positive patients had lower proportions of tumor diameter ≤2 cm (22.73% vs. 45.40%, P=0.026) and basal-like TNBC (54.55% vs. 80.37%, P=0.015). The median follow-up was 71 months (range: 2-170 months), 4 cases (2.16%) were lost to follow-up, 66 cases (35.68%) relapsed or had distant metastasis, and 34 cases (18.38%) died. Survival analysis showed that AJCC stage (HR=7.624, 95% CI: 2.187-26.576, P=0.001) and CD117 positive with P53 diffuse strong positive (HR=3.942, 95% CI: 1.366-11.379, P=0.011) were negatively correlated with the overall survival of TNBC patients.ConclusionsThe expression of CD117 and DOG1 were significantly related to basal-like TNBC, CD117 positive with P53 diffuse strong positive may be correlated with a shorter overall survival and a higher mortality risk
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