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New potential barite reference materials for LA-MC-ICP-MS sulfur isotope analysis with application to hydrothermal barite in the Huayangchuan deposit， western China

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Journal of Earth Science 2024年

作者： Jiali Fu Xinqian He Zhaochu Hu Shuo Yin Jian Ma Kaiyun Chen Wen Zhang National Key Laboratory of Prospecting， Mining and Remote Sense Detecting on Uranium Resources， East China University of Technology State Key Laboratory of Nuclear Resources and Environment， East China University of Technology School of Earth Sciences， East China University of Technology State Key Laboratory of Geological Processes and Mineral Resources， China University of Geosciences Wuhan State Key Laboratory of Continental Dynamics， Department of Geo logy， Northwest University

Sulfur isotopes of S-bearing materials are powerful tools to trace various geological processes and sulfur sources in earth sciences， especially in ore deposits where sulfide-sulfate pair coprecipitates widely. However， in-situ S isotope determination of barite is challenging without natural matrix-matched reference material. In this study， we present two natural barite reference materials （1-YS and 294-YS） for in-situ sulfur isotopic analysis. Independent LA-MC-ICP-MS laboratories were utilized to test the δ34S micron-scale homogeneity of 1-YS and 294-YS barites that have 2s repeatabilities of better than ±0.45 ‰ and ±0.41 ‰， respectively. Meanwhile， the in-situ analysis results are consistent with the results of the bulk analysis by GS-IRMS within uncertainty. The grand mean δ34S values of 1-YS （13.37‰ ± 0.42 ‰， 2s） and 294-YS （14.38‰ ± 0.44 ‰， 2s） are the final recommended values obtained from four independent laboratories. All the results confirm the suitability of 1-YS and 294-YS barite used as calibration materials with respect to in-situ S isotopic analysis. Moreover， the new developed barite reference materials were used as matrix-matched standard to calibrate the barite samples from the Huayangchuan carbonatite-hosted U-polymetallic deposit （Qinling orogenic belt， western China） to obtain δ34S values. Utilizing the temperature-dependent δ34S fractionation of barite-pyrite pair， we calculate the formation temperature of barite （i.e.， 506 to 537 ℃） and the δ34S value of mineralizing fluid （i.e.， -7.11‰ to -7.59 ‰） in the Huayangchuan deposit. The results indicate an involvement of sedimentary sulfur， presumably acting as a potential uranium source （e.g.， upper crustal materials） for the giant Huayangchuan deposit.

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Alkali Aggregate Reaction in Alkali Slag Cement Mortars

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Journal of Wuhan University of Technology(Materials Science) 2002年第3期17卷 60-62页

作者：陈友治 WuhanUniversityofTechTechno9logy

By means of 'Mortar Bar Method',the ratio of cement to aggregate was kept as a constant 1∶2.25,the water cement ratio of the mixture was 0.40,and six prism specimens were prepared for each batch of mixing proportions with dimensions of 10×10×60mm 3 at 38±2℃ and RH≥95%, the influences of content and particle size of active aggregate, sort and content of alkali component and type of slag on the expansion ratios of alkali activated slag cement(ASC) mortars due to alkali aggregate reaction(AAR) were studied. According to atomic absorption spectrometry,the amount of free alkali was measured in ASC mortars at *** results show above factors affect AAR remarkably,but no dangerous AAR will occur in ASC system when the amount of active aggregate is below 15% and the mass fraction of alkali is not more than 5% (Na 2O).Alkali participated in reaction as an independent component, and some hydrates containing alkali cations were produced, free alkalis in ASC system can be reduced ***,slag is an effective inhibitor, the possibility of generating dangerous AAR in ASC system is much lower at same conditions than that in ordinary Portland cement system.

关键词： alkali activated slag cement alkali aggregate reaction alkali active aggregate

Impact of payment source, referral site, and place of residence on outcomes after allogeneic transplantation in Mexico

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World Journal of Transplantation 2024年第2期14卷 76-87页

作者： Andrés Gómez-De León Yesica A López-Mora Valeria García-Zárate Ana Varela-Constantino Sergio U Villegas-De Leon Xitlaly J González-Leal Raúl del Toro-Mijares Anna C Rodríguez-Zúñiga Juan F Barrios-Ruiz Victor Mingura-Ledezma Perla R Colunga-Pedraza Olga G Cantú-Rodríguez César H Gutiérrez-Aguirre Luz Tarín-Arzaga Elías E González-López David Gómez-Almaguer Hematology Service Universidad Autónoma de Nuevo LeónFacultad de Medicina y Hospital Universitario Dr.JoséEleuterio GonzálezMonterrey 64460Nuevo LeónMexico Hemato-logy Service Clínica Gómez AlmaguerMonterrey 64710Nuevo LeónMexico Hematology Service Instituto Tecnológico de Estudios Superiores de MonterreyTec SaludEscuela de Medicina Ignacio SantosMonterrey 64710Nuevo LeónMexico

BACKGROUND The impact of social determinants of health in allogeneic transplant recipients in low-and middle-income countries is poorly *** observational study analyzes the impact of place of residence,referring institution,and transplant cost coverage(out-of-pocket vs government-funded vs private insurance)on outcomes after allogeneic hematopoietic stem cell transplantation(alloHSCT)in two of Mexico's largest public and private *** To evaluate the impact of social determinants of health and their relationship with outcomes among allogeneic transplant recipients in *** In this retrospective cohort study,we included adolescents and adults≥16 years who received a matched sibling or haploidentical transplant from *** were selected without regard to their diagnosis and were sourced from both a private clinic and a public University Hospital in *** payment groups were compared:Out-of-pocket(OOP),private insurance,and a federal Universal healthcare program“Seguro Popular”.Outcomes were compared between referred and institution-diagnosed patients,and between residents of Nuevo Leon and *** outcomes included overall survival(OS),categorized by residence,referral,and payment *** outcomes encompassed early mortality,event-free-survival,graft-versus-host-relapse-free survival,and non-relapse-mortality(NRM).Statistical analyses employed appropriate tests,Kaplan-Meier method,and Cox proportional hazard regression *** software included SPSS and R with tidycmprsk *** Our primary outcome was overall *** included 287 patients,n=164 who lived out of state(57.1%),and n=129 referred from another institution(44.9%).The most frequent payment source was OOP(n=139,48.4%),followed by private insurance(n=75,26.1%)and universal coverage(n=73,25.4%).No differences in OS,event-free-survival,NRM,or graft-versus-host-relapse-free survival were observed for patients dia

关键词： Hematopoietic cell transplant Social determinants of health Geography Haploidentical Out-of-pocket Financial toxicity Survival Health services and outcomes Hematopoietic malignancy Aplastic anemia

Adult celiac disease in the elderly

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World Journal of Gastroenterology 2008年第45期14卷 6911-6914页

作者： Hugh James Freeman Department of Medicine (Gastroentero-logy) University of British Columbia

There is an increased awareness that celiac disease may occur in the elderly although presentations with either diarrhea, weight loss or both may be less common causing delays in diagnosis for prolonged periods. Higher detection rates also seem evident owing to active case screening, largely through serodiagnostic measures. In some elderly patients who are genetically predisposed, it has been hypothesized that celiac disease might be precipitated late in life by an antigen, possibly from an infectious agent. As a result, peptide mimicry or other poorly-defined mechanisms may precipitate an autoimmune gluten-dependent clinical state. Although diarrhea and weight loss occur, only isolated iron deficiency anemia may be present at the time of initial diagnosis. In addition, the risk of other autoimmune disorders, particularly autoimmune thyroiditis, and bone disease, are increased. Osteopenia may also be associated with an increased risk of fractures. Finally, elderly celiacs have an increased risk of malignant intestinal disease, especially lymphoma.

关键词： Celiac disease Elderly Lymphoma Silentceliac disease

Influence of hydrogenation on microstructures and microhardness of Ti6Al4V alloy

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中国有色金属学会会刊：英文版 2008年第3期18卷 506-511页

作者：赵敬伟丁桦赵文娟田学锋侯红亮王耀奇 School of Materials and Metallurgy Northeastern University Beijing Aeronautical Manufacturing Techno logy Research Institute

The microstructures of Ti6Al4V alloy after hydrogenation were investigated by optical microscopy(OM), X-ray diffraction(XRD) and transmission electron microscopy(TEM). The influence of hydrogenation on the hardness of α and β phases was analysed by microhardness testing. The influence of hydrogenation on alloying elements diffusion was studied by electron probe microanalysis(EPMA). The microstructural observation reveals that hydride δ (FCC structure) as well as large number of dislocations precipitate in the specimens with 0.278% and 0.514% hydrogen, and a lot of twins are found in the specimen with 0.514% hydrogen, simultaneously. The result of microhardness testing shows that the hardness of α and β phases increases synchronously with the increase of hydrogen and the hardness increment of β is larger than that of α. According to analysis of EPMA, the diffusion ability of alloy elements Al and V increases after hydrogenation. It is considered that hydrogen solution strengthening and V element diffusion are the main factors causing the hardness of α phase increase with the increase of hydrogen, and the formation of δ hydrides, lattice defects, hydrogen solution strengthening and Al element diffusion jointly cause the hardness of β phase increase with the increasing hydrogen.

关键词：钛铝合金氢化作用氢化物显微硬度固溶强化

In sights into the antineoplastic mechanism of Chelidonium majus via systems pharmacology approach

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Frontiers of Electrical and Electronic Engineering in China 2019年第1期7卷 42-53页

作者： Xinzhe Xiao Zehui Chen Zengrui Wu Tianduanyi Wang Weihua Li Guixia Liu Bo Zhang Yun Tang Shan ghai Key Laboratory of New Drug Desig n School of PharmacyEast China Un iversity of Science and Tech no logyShanghai 200237China Key Laboratory of Xinjiang Phytomedicine Resource and Utilization Ministry of EducationShihezi UniversityShihezi 832002China

Background: The antineoplastic activity of Chelidonium majus has been reported, but its mechanism of action (MoA) is unsuspected. The emerging theory of systems pharmacology may be a useful approach to analyze the complicated MoA of this multi-ingredient traditional Chinese medicine (TCM). Methods: We collected the ingredients and related compound-target interactions of C. majus from several databases. The bSDTNBI (balanced substructure-drug-target network-based inference) method was applied to predict each ingredienfs targets. Pathway enrichment analysis was subsequently conducted to illustrate the potential MoA, and prognostic genes were identified to predict the certain types of cancers that C. majus might be beneficial in treatment. Bioassays and literature survey were used to validate the in silico results? Results: Systems pharmacology analysis demonstrated that C. majus exerted experimental or putative interactions with 18 cancer-associated pathways, and might specifically act on 13 types of cancers. Chelidonine, sanguinarine, chelerythrine, berberine, and coptisine, which are the predominant components of C. majus, may suppress the cancer genes by regulating cell cycle, inducing cell apoptosis and inhibiting proliferation. Conclusions: The antineoplastic MoA of C. majus was investigated by systems pharmacology approach. C. majus exhibited promising pharmacological effect against cancer, and may consequently be useful material in further drug development. The alkaloids are the key components in C. majus that exhibit anticancer activity.

关键词： systems phannacology mechanism of action traditional Chinese medicine Chelidonium majus

Grinding Characteristics of Multi-component Cement-based Material

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 126-129页

作者：卢迪芬 Institute of Materials Science and Engineering South China University of Techno logyGuangzhou 510640China

The grinding characteristics of two or multi-component material of cli nker with limestone, blast furnace slag and fly ash were studied. Investigation was carried out on the particle size distribution, the Blaine fineness and the s ieve residue of the separate and interground products. The relative contents of clinker and limestone in different size fractions of the interground product wer e examined, and the interaction of two components, which have different grindabi lities, was analyzed. The results show there exists a selective grinding effect during intergrinding, one component can help or hinder the grinding of the other . Making good use of this interaction appropriately not only enhances the grinda bilities of two or multi-component mixtures, which can promote the grinding pro cess of clinker with industrial wastes, but also improves their particle size di stribution and properties.

关键词： intergrinding separate grinding selective grinding particle size distribut ion multi-component cement-based material

Endoscopic findings in patients with upper gastrointestinal bleeding clinically classified into three risk groups prior to endoscopy

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World Journal of Gastroenterology 2008年第32期14卷 5046-5050页

作者： Leonardo Tammaro Maria Carla Di Paolo Angelo Zullo Cesare Hassan Sergio Morini SebastianoCaliendo Lorella Pallotta Gastroenterology and DigestiveEndoscopy Ⅱ "San Giovanni Addolorata" Hospital Gastroentero-logy and Digestive Endoscopy "Nuovo Regina Margherita"Hospital

AIM: To investigate in a prospective study whether a simplifi ed clinical score prior to endoscopy in upper gastrointestinal bleeding (UGIB) patients was able to predict endoscopic findings at urgent endoscopy. METHODS: All consecutive UGIB patients referred to a single endoscopic center during a 16 mo period were enrolled. Before endoscopy patients were strati- fied according to a simple clinical score (T-score), including T1 (high-risk), T2 (intermediate-risk) and T3 (low-risk). Endoscopy was performed in all cases within 2 h, and high-risk stigmata were considered for further analysis. RESULTS: Out of the 436 patients included into the study, 126 (29%) resulted to be T1, 135 (31%) T2, and 175 (40%) T3. Overall, stigmata of recent haem-orrhage (SRH) were detected in 118 cases (27%). SRH occurred more frequently in T1 patients than in T2/T3 cases (85% vs 3.2%; χ2 = 304.5309, P < 0.001). Older age (t=3.311; P < 0.01) and presence of comor-bidities (χ2 = 14.7458; P < 0.01) were more frequently detected in T1 than in T2/T3 patients. CONCLUSION: Our simplifi ed clinical score appeared to be associated with the detection of endoscopic findings which may deserve urgent endoscopy. A further,randomised study is needed to assess its accuracy in safely scheduling endoscopy in UGIB patients.

关键词： Upper gastrointestinal bleeding Urgentendoscopy Timing score Endoscopic treatment Oesophageal varices Peptic ulcer

Effect of Network Modifiers on Spectroscopic Properties of Erbium-doped Phosphate Glasses

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Journal of Wuhan University of Technology(Materials Science) 2005年第1期20卷 60-63页

作者：杨钢锋 Institute of Optical Communication Materials South China University of Techno logyGuangzhou 510641China

The integrated absorption cross section Σ abs, peak emis sion cross section σ emi, Judd-Ofeld intensity parameters Ω t(t=2,4,6), and spontaneous emission probability A R of Er 3+ ions were determined fo r Erbium doped alkali and alkaline earth phosphate glasses. It is found the comp ositional dependence of σ emi is almost similar to that of Σ abs, wh ich is determined by the sum of Ω t (3Ω 2+10Ω 4+21Ω 6). In addition, the compositional dependence of Ω t was studied in these glass systems. As a resu lt, compared with Ω 4 and Ω 6, the Ω 2 has a stronger compositional depend ence on the ionic radius and content of modifiers. The covalency of Er-O bonds in phosphate glass is weaker than that in silicate glass, germanate glass, alumi nate glass, and tellurate glass, since Ω 6 of phosphate glass is relatively la rge. A R is affected by the covalency of the Er 3+ ion sites and correspon ds to the Ω 6 value.

关键词： erbium doped phosphate laser glasses spectroscopic properties network modifi ers compositional dependence