High-precision data on U and Th contents and Th/U ratios of zircon obtained using secondary ion mass spectrometry analysis have been collected from the literature. Zircon in the granitic rocks has median values of 350...High-precision data on U and Th contents and Th/U ratios of zircon obtained using secondary ion mass spectrometry analysis have been collected from the literature. Zircon in the granitic rocks has median values of 350 ppm U, 140 ppm Th, and Th/U=0.52; the recommended zircon-melt partition coefficients are 81 for Du and 8.2 for DTh. In zircon from mafic and intermediate rocks, the median values are 270 ppm U, 170 ppm Th, and Th/U=0.81, and the recommended zirconmelt partition coefficients are 169 for Du and 59 for DTh. The U and Th contents and Th/U ratios of magmatic zircon are low when zircon crystallizes in equilibrium with the melt. Increasing magma temperature should promote higher Th contents relative to U contents, resulting in higher Th/U ratios for zircon in mafic to intermediate rocks than in granitic rocks. However, when zircon crystallizes in disequilibrium with the melt, U and Th are more easily able to enter the zircon lattice, and their contents and Th/U ratios depend mainly on the degree of disequilibrium. The behavior of U and Th in magmatic zircon can be used as a geochemical indicator to determine the origins and crystallization environments of magmatic zircon.展开更多
In luminescence and ESR dating methods,total count rate from thick source alpha counting is commonly used fox estimating annual dose with assumption of equal activities for both uranium and thorium decay chains.This i...In luminescence and ESR dating methods,total count rate from thick source alpha counting is commonly used fox estimating annual dose with assumption of equal activities for both uranium and thorium decay chains.This is equal to a Th/U weight ratio of 3.2.The systematic error in total dose rate due to uncertainty of the ratio is calculated.It is found that the error is insignificant for uniformly distributed samples such as sediment,but can be significant for some extreme circumstances.展开更多
AIM: To investigate the role of T helper 17 cells (Th17) and regulatory T cells (Treg) in hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF).METHODS: We enrolled 79 patients with HBV infection into ...AIM: To investigate the role of T helper 17 cells (Th17) and regulatory T cells (Treg) in hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF).METHODS: We enrolled 79 patients with HBV infection into the study, 50 patients with HBV-related ACLF and 29 patients with chronic hepatitis B (CHB), from the First Affiliated Hospital of Medical College from January 2009 to June 2012. The ACLF patients were diagnosed according to the criteria recommended by The 19th Conference of the Asian Pacific Association for the Study of the Liver in 2009. Twenty healthy individuals with a similar gender and age structures to the two patient groups were also included as the normal controls (NC). Of the 50 ACLF patients, 28 were subsequently classified as non-survivors: 19 patients died from multiorgan failure, 3 underwent liver transplantation, and 6 discontinued therapy during follow-up because of financial reasons. The remaining 22 ACLF patients whose liver and anticoagulation function recovered to nearly normal levels within the next 6 mo were classified as survivors. The number of circulating Treg and Th17 cells was determined upon diagnosis and during the 8th week of follow-up through flow cytometry. RESULTS: The percentage of circulating Treg cells in the ACLF group was significantly higher than that in the CHB group (5.50% ± 1.15% vs 3.30% ± 1.13%, P < 0.01). The percentages of circulating Th17 cells in the ACLF and the CHB groups were significantly higher than that in the NC group (6.32% ± 2.22% vs 1.56% ± 0.44%, P < 0.01; 3.53% ± 1.65% vs 1.56% ± 0.44%, P < 0.01). No significant difference in Treg cell to Th17 cell ratio was observed between the ACLF group and the CHB group (0.98 ± 0.44 vs 1.12 ± 0.64, P = 0.991), whereas those in the two HBV infection groups were significantly lower than that in the NC group (1.85 ± 1.22; both P < 0.01). The percentage of Treg cells in the survivors during the 8th week of follow-up was significantly lower than that during peak ACLF severity [total bilirubin (TBIL) peak] (3.45% ± 0.97% vs 5.18% ± 1.02%, P < 0.01). The percentage of Th17 cells in survivors during the 8th week of follow-up was significantly lower than that during the peak TBIL (2.89% ±0.60% vs 5.24% ± 1.46%; P < 0.01). The Treg cell to Th17 cell ratio during the 8 th week of follow-up was significantly higher than that during the TBIL peak (1.22 ± 0.36 vs 1.10 ± 0.54; P < 0.05). CONCLUSION: Restoring the Treg cell to Th17 cell ratio during the follow-up phase of ACLF could maintain the immune system at a steady state, which favours good prognosis.展开更多
Aim: To investigate the relationship between 2D:4D and testosterone in men attending an infertility clinic and men drawn from the general population. Methods: Data on 2D:4D and testosterone from two samples were colle...Aim: To investigate the relationship between 2D:4D and testosterone in men attending an infertility clinic and men drawn from the general population. Methods: Data on 2D:4D and testosterone from two samples were collected: (1) 43 men attending an infertility clinic, and (2) 51 men drawn from the general population without regard to fertility. Results: In sample (1) there were negative associations between 2D:4D and testicular function, and men with lower 2D:4D in their right compared to left hand had higher testosterone levels than men with higher 2D:4D in their right compared to left hand. Sample (2) showed no significant associations between 2D:4D or side differences in 2E>:4D and testosterone. Conclusion: Adult levels of testosterone may be related to aspects of 2D:4D in samples which contain men with compromised testicular function, but not in men from normative samples. Associations between 2D:4D and fertility-associated traits probably arise from early organisational effects of testosterone rather than from activational effects of current testosterone.展开更多
The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previ...The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide deposits.However,the sulfide chronology and hydrothermal activity of the YHF remain poorly constrained.In this study,mineralogical analyses and 230Th/U dating were performed.Hydrothermal activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the YHF.The 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the SWIR.Hydrothermal activity in the SWIR has been relatively active over the past20 ka.In contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in duration.The maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 ka.There was a slight positive correlation between the maximal age and estimated surface area or estimated tonnage.The minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic systems.The ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)deposits.The results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges.展开更多
Statistical biases may be introduced by imprecisely quantifying background radiation reference levels. It is, therefore, imperative to devise a simple, adaptable approach for precisely describing the reference backgro...Statistical biases may be introduced by imprecisely quantifying background radiation reference levels. It is, therefore, imperative to devise a simple, adaptable approach for precisely describing the reference background levels of naturally occurring radionuclides (NOR) in mining sites. As a substitute statistical method, we suggest using Bayesian modeling in this work to examine the spatial distribution of NOR. For naturally occurring gamma-induced radionuclides like 232Th, 40K, and 238U, statistical parameters are inferred using the Markov Chain Monte Carlo (MCMC) method. After obtaining an accurate subsample using bootstrapping, we exclude any possible outliers that fall outside of the Highest Density Interval (HDI). We use MCMC to build a Bayesian model with the resampled data and make predictions about the posterior distribution of radionuclides produced by gamma irradiation. This method offers a strong and dependable way to describe NOR reference background values, which is important for managing and evaluating radiation risks in mining contexts.展开更多
The Oxia mineralized granite is the product of differentiation in the external parts of the Florina magmatic mass. Acidic hydrothermal solutions either of magmatic or of meteoric origin reacted with the upper tectonic...The Oxia mineralized granite is the product of differentiation in the external parts of the Florina magmatic mass. Acidic hydrothermal solutions either of magmatic or of meteoric origin reacted with the upper tectonically fractured parts of the Florina granite and became enriched in iron, thorium, uranium, zircon and rare-earth elements. The most abundant alteration minerals are sericite and quartz, while the minerals of the mineralization bands include magnetite, hematite, thorite, monazite and zircon. The outer parts of the Oxia granite made it easy the percolation of hydrothermal solutions from the deeper heater to the upper cooler parts of the granite which acted as a hot spot.展开更多
基金supported by the National Natural Science Foundation of China(Grant No. 40972058)the research grants(2008-Ⅰ-02 and 2008-Ⅱ-08)from the State Key Laboratory for Mineral Deposit Research,Nanjing University
文摘High-precision data on U and Th contents and Th/U ratios of zircon obtained using secondary ion mass spectrometry analysis have been collected from the literature. Zircon in the granitic rocks has median values of 350 ppm U, 140 ppm Th, and Th/U=0.52; the recommended zircon-melt partition coefficients are 81 for Du and 8.2 for DTh. In zircon from mafic and intermediate rocks, the median values are 270 ppm U, 170 ppm Th, and Th/U=0.81, and the recommended zirconmelt partition coefficients are 169 for Du and 59 for DTh. The U and Th contents and Th/U ratios of magmatic zircon are low when zircon crystallizes in equilibrium with the melt. Increasing magma temperature should promote higher Th contents relative to U contents, resulting in higher Th/U ratios for zircon in mafic to intermediate rocks than in granitic rocks. However, when zircon crystallizes in disequilibrium with the melt, U and Th are more easily able to enter the zircon lattice, and their contents and Th/U ratios depend mainly on the degree of disequilibrium. The behavior of U and Th in magmatic zircon can be used as a geochemical indicator to determine the origins and crystallization environments of magmatic zircon.
文摘In luminescence and ESR dating methods,total count rate from thick source alpha counting is commonly used fox estimating annual dose with assumption of equal activities for both uranium and thorium decay chains.This is equal to a Th/U weight ratio of 3.2.The systematic error in total dose rate due to uncertainty of the ratio is calculated.It is found that the error is insignificant for uniformly distributed samples such as sediment,but can be significant for some extreme circumstances.
基金Supported by The Major National Science and Technology Projects for Infectious Diseases (11th and 12th Five Year, China),No. 2008ZX10002-007, No. 2012ZX10002-007the Foundation of Shaanxi Provincial Science and Technology Plan Projects,No. 2011K14-09-09
文摘AIM: To investigate the role of T helper 17 cells (Th17) and regulatory T cells (Treg) in hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF).METHODS: We enrolled 79 patients with HBV infection into the study, 50 patients with HBV-related ACLF and 29 patients with chronic hepatitis B (CHB), from the First Affiliated Hospital of Medical College from January 2009 to June 2012. The ACLF patients were diagnosed according to the criteria recommended by The 19th Conference of the Asian Pacific Association for the Study of the Liver in 2009. Twenty healthy individuals with a similar gender and age structures to the two patient groups were also included as the normal controls (NC). Of the 50 ACLF patients, 28 were subsequently classified as non-survivors: 19 patients died from multiorgan failure, 3 underwent liver transplantation, and 6 discontinued therapy during follow-up because of financial reasons. The remaining 22 ACLF patients whose liver and anticoagulation function recovered to nearly normal levels within the next 6 mo were classified as survivors. The number of circulating Treg and Th17 cells was determined upon diagnosis and during the 8th week of follow-up through flow cytometry. RESULTS: The percentage of circulating Treg cells in the ACLF group was significantly higher than that in the CHB group (5.50% ± 1.15% vs 3.30% ± 1.13%, P < 0.01). The percentages of circulating Th17 cells in the ACLF and the CHB groups were significantly higher than that in the NC group (6.32% ± 2.22% vs 1.56% ± 0.44%, P < 0.01; 3.53% ± 1.65% vs 1.56% ± 0.44%, P < 0.01). No significant difference in Treg cell to Th17 cell ratio was observed between the ACLF group and the CHB group (0.98 ± 0.44 vs 1.12 ± 0.64, P = 0.991), whereas those in the two HBV infection groups were significantly lower than that in the NC group (1.85 ± 1.22; both P < 0.01). The percentage of Treg cells in the survivors during the 8th week of follow-up was significantly lower than that during peak ACLF severity [total bilirubin (TBIL) peak] (3.45% ± 0.97% vs 5.18% ± 1.02%, P < 0.01). The percentage of Th17 cells in survivors during the 8th week of follow-up was significantly lower than that during the peak TBIL (2.89% ±0.60% vs 5.24% ± 1.46%; P < 0.01). The Treg cell to Th17 cell ratio during the 8 th week of follow-up was significantly higher than that during the TBIL peak (1.22 ± 0.36 vs 1.10 ± 0.54; P < 0.05). CONCLUSION: Restoring the Treg cell to Th17 cell ratio during the follow-up phase of ACLF could maintain the immune system at a steady state, which favours good prognosis.
文摘Aim: To investigate the relationship between 2D:4D and testosterone in men attending an infertility clinic and men drawn from the general population. Methods: Data on 2D:4D and testosterone from two samples were collected: (1) 43 men attending an infertility clinic, and (2) 51 men drawn from the general population without regard to fertility. Results: In sample (1) there were negative associations between 2D:4D and testicular function, and men with lower 2D:4D in their right compared to left hand had higher testosterone levels than men with higher 2D:4D in their right compared to left hand. Sample (2) showed no significant associations between 2D:4D or side differences in 2E>:4D and testosterone. Conclusion: Adult levels of testosterone may be related to aspects of 2D:4D in samples which contain men with compromised testicular function, but not in men from normative samples. Associations between 2D:4D and fertility-associated traits probably arise from early organisational effects of testosterone rather than from activational effects of current testosterone.
基金The National Key R&D Program of China under contract No.2022YFE0140200the National Natural Science Foundation of China under contract Nos 42127807 and 42006074+1 种基金the China Ocean Mineral Resources R&D Association Project under contract Nos DY135-S1-1-02 and DY135-S1-1-01the Macao Science and Technology Development Fund under contract No.FDCT-002/2018/A1。
文摘The Yuhuang hydrothermal field(YHF)is located between the Indomed and Gallieni fracture zones near the top of the off-axis slope on the south rift wall of Segment 29 on the ultraslow Southwest Indian Ridge(SWIR).Previous studies have shown that sulfides in the YHF formed during different mineralization episodes and the YHF has the greatest potential for the formation of large-scale seafloor massive sulfide deposits.However,the sulfide chronology and hydrothermal activity of the YHF remain poorly constrained.In this study,mineralogical analyses and 230Th/U dating were performed.Hydrothermal activity may start about(35.9±2.3)ka from the southwest part of the YHF and may cease about(708±81)a ago from the northeast part of the YHF.The 74 nonzero chronological data from hydrothermal sulfide samples provide the first quantitative characterization of the spatial and temporal history along the SWIR.Hydrothermal activity in the SWIR has been relatively active over the past20 ka.In contrast,between 40 ka and 100 ka,hydrothermal activity was relatively infrequently and short in duration.The maximum activity occurred at 15–11 ka,9–7 ka,6–0.2 ka.There was a slight positive correlation between the maximal age and estimated surface area or estimated tonnage.The minimum mass accumulation rate of YHF is about 278 t/a,which is higher than most HFs related to ultramafic systems.The ultraslow spreading SWIR has the greatest potential to form large-scale seafloor massive sulfides(SMS)deposits.The results of this study provide new insights into the metallogenic mechanism of hydrothermal sulfides along ultraslow-spreading ridges.
文摘Statistical biases may be introduced by imprecisely quantifying background radiation reference levels. It is, therefore, imperative to devise a simple, adaptable approach for precisely describing the reference background levels of naturally occurring radionuclides (NOR) in mining sites. As a substitute statistical method, we suggest using Bayesian modeling in this work to examine the spatial distribution of NOR. For naturally occurring gamma-induced radionuclides like 232Th, 40K, and 238U, statistical parameters are inferred using the Markov Chain Monte Carlo (MCMC) method. After obtaining an accurate subsample using bootstrapping, we exclude any possible outliers that fall outside of the Highest Density Interval (HDI). We use MCMC to build a Bayesian model with the resampled data and make predictions about the posterior distribution of radionuclides produced by gamma irradiation. This method offers a strong and dependable way to describe NOR reference background values, which is important for managing and evaluating radiation risks in mining contexts.
文摘The Oxia mineralized granite is the product of differentiation in the external parts of the Florina magmatic mass. Acidic hydrothermal solutions either of magmatic or of meteoric origin reacted with the upper tectonically fractured parts of the Florina granite and became enriched in iron, thorium, uranium, zircon and rare-earth elements. The most abundant alteration minerals are sericite and quartz, while the minerals of the mineralization bands include magnetite, hematite, thorite, monazite and zircon. The outer parts of the Oxia granite made it easy the percolation of hydrothermal solutions from the deeper heater to the upper cooler parts of the granite which acted as a hot spot.
