The role of metakaolin in the properties of Portland cement hydrated with ground water and sea water was described by magnetic susceptibility study. Cement pastes containing 0wt%, 10wt%, 20wt% and 30wt% replacement of...The role of metakaolin in the properties of Portland cement hydrated with ground water and sea water was described by magnetic susceptibility study. Cement pastes containing 0wt%, 10wt%, 20wt% and 30wt% replacement of metakaolin and in a water/cement （W/C） ratio of 0.4 were prepared. The susceptibility at different hydration periods was determined by Faraday Curie balance and it was related to the changes in setting time and compressive strength of admixtured cement. Compared with sea water-treated cement paste, the magnetic susceptibility of ground water-treated cement paste is higher in value. The observed result shows that, irrespective of water, the magnetic susceptibility increases with increasing metakaolin percentage replacement level in cement.展开更多
Purpose-The utilization of alkali-free accelerators,primarily based on aluminum sulfate,in shotcrete often leads to significant shrinkage and cracking,jeopardizing long-term durability.This study aims to mitigate this...Purpose-The utilization of alkali-free accelerators,primarily based on aluminum sulfate,in shotcrete often leads to significant shrinkage and cracking,jeopardizing long-term durability.This study aims to mitigate this issue by investigating the efficacy of silica fume(SF)and fly ash(FA),individually and combined,in controlling the shrinkage deformation of shotcrete.Design/methodology/approach-Shotcrete mixtures were prepared with cement partially replaced by SF,FA,or their combination(SF-FA).Aluminum sulfate was used as an accelerator.The shrinkage behavior under sealed and dry conditions was monitored.The underlying mechanisms were elucidated through hardened airvoid analysis,mercury intrusion porosimetry(MIP),and internal humidity tracking.Findings-Contrary to some previous studies,both individual and combined incorporation of mineral admixtures reduced the 28-day shrinkage.The SF-FA composite exhibited the most substantial reduction(23.72%sealed,17.76%dry),followed by SF alone(18.11%sealed)and FA alone(11.35%sealed).Mechanism analysis revealed that the admixtures refined the pore structure,reduced the volume of harmful pores,and,crucially,optimized the air-void system by increasing the population of fine bubbles.This created an internal buffering effect that alleviates capillary stress.The synergistic effect in the SF-FA group is attributed to complementary pore-filling at dual scales.Originality/value-This work demonstrates that,within an aluminum sulfate-accelerated shotcrete system,silica fume can effectively reduce shrinkage when its pore-refining effect is counterbalanced by a welloptimized micro-bubble network.It provides the first comprehensive evidence of the synergistic shrinkagereducing mechanism of SF and FA in such systems,offering a practical strategy for mix design optimization to enhance the volume stability of shotcrete.展开更多
China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic ...China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic groups,with limited research on the genetic formation of the hereditary elite family,especially considering their abundant archaeological record and clear material identity.In this study,we obtain the ancient genome of a hereditary elite family,Gao Bin(高宾,503 AD–572 AD),at 0.6473-fold coverage with 475,132 single-nucleotide polymorphisms(SNPs)on the 1240k panel.His mitochondrial haplogroup belongs to Z4 and Y-haplogroup to O1a1a2b-F2444∗.The genetic profile of Gao Bin is most similar to that of the northern Han Chinese.He can be modeled as deriving all his ancestry from Late Neolithic to Iron Age Yellow River farmers without influence from Northeast Asia,Korea,or the Mongolian Plateau.Our study sheds light on the genetic formation of hereditary elite families in the context of the Southern and Northern Dynasties ethnic integration.展开更多
This study investigated the factors contributing to intravenous admixture preparation errors(IAPEs)within Pharmacy Intravenous Admixture Services(PIVAS).A retrospective analysis was conducted on IAPEs documented in th...This study investigated the factors contributing to intravenous admixture preparation errors(IAPEs)within Pharmacy Intravenous Admixture Services(PIVAS).A retrospective analysis was conducted on IAPEs documented in the PIVAS unit of a large multi-specialty hospital in China,which houses over 2000 beds,covering the period from January 1,2015 to December 31,2022.Drug preparation records were examined using a generalized linear mixed model(GLMM)to identify both univariate and multivariate factors associated with IAPE occurrences.A total of 824 IAPE cases were recorded during the study period,yielding an overall error rate of 0.018%.Univariate analysis identified drug categories(general drugs,anti-infective drugs,and antineoplastic drugs),preparation time(workdays),and years of work experience as significant determinants(P<0.05).Multivariate analysis further confirmed that drug categories(general and antineoplastic drugs),preparation time(workdays),and work experience remained statistically significant predictors of IAPE incidence(P<0.05).IAPEs in PIVAS were influenced by multiple factors,predominantly those related to personnel and drug characteristics.Targeted interventions,informed by multivariate analysis,are essential to mitigating these errors and enhancing medication safety.展开更多
Four typical admixtures,polycarboxylate superplasticiser(PCE),tartaric acid(TA),sorbitol and polyacrylamide(PAM),were selected to systematically investigate their regulatory mechanisms on the formation of ettringite t...Four typical admixtures,polycarboxylate superplasticiser(PCE),tartaric acid(TA),sorbitol and polyacrylamide(PAM),were selected to systematically investigate their regulatory mechanisms on the formation of ettringite through Fourier transform infrared spectroscopy,X-ray diffraction,particle size analysis and nucleation kinetic model.The experimental results indicate that the admixtures alter the formation of ettringite through physical adsorption,complexation and solution viscosity modulation without changing its chemical structure.Low concentrations of PCE inhibit size growth by forming an adsorption layer on the surface of ettringite,whereas high concentrations of PCE alter the size change of ettringite by modulating the distribution of ionic concentrations.TA significantly reduces the size of ettringite by complexing Ca^(2+).Sorbitol and PAM promote the local growth of ettringite at low concentrations,leading to larger sizes.But at high concentrations,the size growth of ettringite is inhibited due to the increase in viscosity or the enhancement of complexation.Matlab nucleation kinetic modelling further shows that the addition of admixtures enhances the initial nucleation during ettringite synthesis,with values ranging from 14.45%to 114.25%.However,the subsequent nucleation rate of ettringite is significantly affected,decreasing by 12.79%to 71.74%.The results provide a theoretical basis for the design of ettringite materials and the optimisation of the application of admixtures.展开更多
Crystalline admixtures(CA),also known as permeability reducer admixtures,are used in binder-based materials to improve concrete durability by reducing water permeability depth,increasing compressive strength,and stimu...Crystalline admixtures(CA),also known as permeability reducer admixtures,are used in binder-based materials to improve concrete durability by reducing water permeability depth,increasing compressive strength,and stimulating crack healing.The purpose of this study is to evaluate the potential of crystalline admixtures to enhance the self-healing characteristics and durability attributes of concrete and to contribute to the understanding of their role in the design of long-term efficiency and sustainability.The 28 days specimens of M40 grade concrete were prepared by adding CA and cast as 150 mm cubes,25×25×285 mm prisms and disks with a diameter of 100 mm and height of 50 mm.All samples were then tested for compressive strength,water permeability,dry shrinkage,sodium sulfate attack test,Rapid Chloride Migration Test(RCMT),and rapid chloride penetration test(RCPT)to study the behavior of incorporating crystalline admixtures in concrete.The conclusion drawn from this study was that the addition of a crystalline admixture of 0.8%resulted in an increase in the compressive strength by 7.98%and a decrease in water penetration depth through the cube by 71.5%,while the dry shrinkage of the specimen incorporated with the crystalline admixture was 65.21%less than that of the specimen without the crystalline admixture.These results substantiate the beneficial role of CA in increasing the durability of concrete through increased strength,lower permeability,and better dimensional stability,thus making crystalline admixtures beneficial for incorporation into high-performance concrete applications.展开更多
An evaluation method for self-healing capacity was designed,which includes the control of initial cracks and subsequent permeability testing.This method was employed to evaluate the self-healing behavior of mortars in...An evaluation method for self-healing capacity was designed,which includes the control of initial cracks and subsequent permeability testing.This method was employed to evaluate the self-healing behavior of mortars incorporating crystalline admixtures(CAs)under various conditions,including water immersion,limewater soaking,and wet-dry cycles,with varying CA dosages and crack widths.The experimental results indicate that cement possesses inherently self-healing capability.Limewater environments inhibits healing compared with water immersion;however,wet-dry cycles enhance the effectiveness of higher CA dosages.Increasing the CA content can not improve healing performance,and wide cracks(0.3 mm)substantially reduce the intrinsic self-healing potential of cement.展开更多
In this paper,the effects of four different mineral ginseng materials on the mechanical properties of mortar were studied,and the results showed that high territory,fly ash,and silica fume had an inhibitory effect on ...In this paper,the effects of four different mineral ginseng materials on the mechanical properties of mortar were studied,and the results showed that high territory,fly ash,and silica fume had an inhibitory effect on the drying shrinkage of mortar,and mineral powder increased the drying shrinkage of mortar.The high territory in the mineral admixture has the best effect on the inhibition of mortar drying shrinkage.The compressive strength and flexural strength of the mortar can be improved by adding a certain amount of mineral admixture,which increases the compressive strength by about 20%-40%and the flexural strength by about 20%-30%compared with the control group,and the improvement effect difference between different components is not large.展开更多
1.In recent years,climate change has led to drought and severe bark beetle infestations,affecting Norway spruce(Picea abies)across Europe,with detrimental consequences for forest owners,the forestry sector and associa...1.In recent years,climate change has led to drought and severe bark beetle infestations,affecting Norway spruce(Picea abies)across Europe,with detrimental consequences for forest owners,the forestry sector and associated industries.As a result,silviculture now faces the challenge of identifying tree species more resilient to these stressors to mitigate the impacts on forest management,forest-dependent economies and rural livelihoods.The North American Douglas-fir(Pseudotsuga menziesii)has emerged as a promising conifer species,better suited to future climate conditions and capable of producing high timber yields.2.Non-native tree species may affect native biodiversity,yet the impacts of Douglas-fir on native forest biodiversity are not clear.A comprehensive review evaluating the impact of Douglas-fir on faunal and floral biodiversity in European forests is lacking.3.Here,we present the results of a systematic literature review on Douglas-fir effects on native biodiversity,focusing on studies conducted in Europe.For arthropods,sufficient studies were found to do more detailed quantitative assessments.For fungi,birds,plants and soil fauna some studies existed,but only qualitative evaluations could be made.Other taxa were not investigated.4.In the present literature,the effects of Douglas-fir inclusion in stands on native biodiversity,compared to stands of solely native tree species,were mostly non-significant(78.6%,based on 32 studies).Positive effects were noted in 12%of cases,while negative effects were observed in 9.4%(total of 1,936 effects).Above-ground fauna was more extensively studied than below-ground fauna.Mechanisms proposed to explain taxa responses were often discussed but not always formally tested.For arthropods,there were varying effects on diversity between studies evaluating different scales(i.e.,tree-scale vs.stand-scale).In general,differences in effects depended on a range of factors,including stand composition and structure,season,and sampling site and period.5.Our review indicates limited evidence of adverse effects of Douglas-fir on biodiversity in European forests,highlighting a significant knowledge gap due to the scarcity of studies.Douglas-fir's impact on biodiversity likely varies depending on the forest type and management practices.Further research in diverse contexts is crucial to determine optimal levels of admixture and guide forest management.展开更多
To mitigate the severe abrasion damage caused by high-velocity water flow in hydraulic engineering applications in Xizang, China, this study systematically optimized key mix design parameters, including aggregate grad...To mitigate the severe abrasion damage caused by high-velocity water flow in hydraulic engineering applications in Xizang, China, this study systematically optimized key mix design parameters, including aggregate gradation, sand ratio, fly ash content, and superplasticizer dosage. Based on the optimized mix, the combined effects of an abrasion-resistance enhancement admixture (AEA) and silica fume (SF) on the abrasion resistance of self-compacting concrete (SCC) were examined. The results demonstrated that the appropriate incorporation of AEA and SF significantly improved the abrasion resistance of SCC without compromising its workability. The proposed mix design not only achieves superior abrasion resistance but also provides practical guidance for the material design and engineering application of durable hydraulic concrete in harsh environments. Future research will focus on comprehensive durability assessments by simulating extreme hydraulic conditions, including sustained exposure to high-velocity sediment-laden flows, repeated freeze-thaw cycles, and corrosive salt spray environments, to thoroughly evaluate the long-term performance evolution of abrasion-resistant self-compacting concrete. Meanwhile, advanced microstructural analytical methods should be applied toelaborate the synergistic mechanisms of abrasion-resistance enhancement admixture (AEA), silica fume (SF), and steel fibers in altering the hydration product formation, optimizing the distribution of pore structure, and strengthening interfacial transition zones, to establish a solid scientific foundation for the development of high-performance composite materials.展开更多
In the present study, we aimed to analyze the irrational medical orders and evaluate the effect of pharmacy intervention on pharmacy intravenous admixture services of outpatient and emergency departments in our hospit...In the present study, we aimed to analyze the irrational medical orders and evaluate the effect of pharmacy intervention on pharmacy intravenous admixture services of outpatient and emergency departments in our hospital. The irrational medical orders of PIVAS at the outpatient and emergency departments were retrospectively analyzed in Jun. 2015. We strengthened the pharmacy intervention on irrational medical orders since July 2015. All the cases were selected by systematic sampling method. Cased studied in Jun. 2015 served as the control group, whereas those studied in Jan. 2016 served as the intervention group. The irrational rate and the irrational number of daily average were compared between the control group and intervention group. The common type of irrational outpatient and emergency intravenous orders mainly included irrational use of solvents, irrational dosing interval and inappropriate compatibility of drugs. The irrational rate was reduced from 17.4% to 3.3% （P〈0.01）, and the irrational number of daily average was decreased from 5.23 to 1.00 （P〈0.01）. Pharmacy intervention can reduce the irrational rate of medical orders in our hospital, which is of great significance to promote rational drug use and improve medical quality.展开更多
In order to investigate the effects of two mineral admixtures （i. e., fly ash and ground slag）on initial defects existing in concrete microstructures, a high-resolution X-ray micro-CT（ micro-focus computer tomogra...In order to investigate the effects of two mineral admixtures （i. e., fly ash and ground slag）on initial defects existing in concrete microstructures, a high-resolution X-ray micro-CT（ micro-focus computer tomography）is employed to quantitatively analyze the initial defects in four series of highperformance concrete （HPC）specimens with additions of different mineral admixtures. The nigh-resolution 3D images of microstructures and filtered defects are reconstructed by micro- CT software. The size distribution and volume fractions of initial defects are analyzed based on 3D and 2D micro-CT images. The analysis results are verified by experimental results of watersuction tests. The results show that the additions of mineral admixtures in concrete as cementitious materials greatly change the geometrical properties of the microstructures and the spatial features of defects by physical-chemistry actions of these mineral admixtures. This is the major cause of the differences between the mechanical behaviors of HPC with and without mineral admixtures when the water-to-binder ratio and the size distribution of aggregates are constant.展开更多
In order to reduce the cohesive force between pavement and ice, the approach of pavement surface coating with hydrophobic admixtures is investigated. The deicing effect of this approach is examined by the contact angl...In order to reduce the cohesive force between pavement and ice, the approach of pavement surface coating with hydrophobic admixtures is investigated. The deicing effect of this approach is examined by the contact angle test and the shear test. The durability of the approach is examined by the accelerated abrasion test, and the skid resistance of the pavement with surface coating is examined by the British pendulum test and the surface texture depth test. In the contact angle test, the contact angle between hydrophobic admixture and water is 100.2°. In the shear test, the maximum shear stress is 0.06 MPa for the specimen coated with hydrophobic admixture, which is much lower than that of the specimen without hydrophobic admixture coating, 3.5 MPa. Furth- ermore, the ice and asphalt surface are completely separated for the coated specimen while not for the uncoated specimen. Based on the accelerated abrasion test, the residual hydro- phobic admixture in the veins of the pavement after abrasion still has a deicing effect. From the skid resistance tests, the British pendulum number （BPN） and the texture depth （TD） of the specimen coated with hydrophobic admixtures are larger than those of the standard requirements. The overall experi-mental observation indicates that the approach can effectively reduce close contact between asphalt pavement and ice; therefore, it can be a promising solution to road icing problems in winter.展开更多
The expansion and micro-cracks of the mortar with composite mineral admixtures （fly ash, zeolite and slag） due to the alkali-silica reaction （ASR） are studied. Results show that composite mineral admixtures cannot...The expansion and micro-cracks of the mortar with composite mineral admixtures （fly ash, zeolite and slag） due to the alkali-silica reaction （ASR） are studied. Results show that composite mineral admixtures cannot absolutely diminish the ASR of mortar bars with the low-alkali cement and a highly reactive aggregate. But the expansion rate and the deleterious expansion of the mortar bar are mostly reduced with increasing composite mineral admixture. The influence of mineral admixtures on the fluidity of the paste and the strength of the mortar is also studied.展开更多
The rice husk ash （ RHA） and silica （ Si02） nanoparticles are prepared from rice husk charcoal （RHC） by the methods of ventilated calcining and chemical precipitation, respectively, to remove the residual carbon...The rice husk ash （ RHA） and silica （ Si02） nanoparticles are prepared from rice husk charcoal （RHC） by the methods of ventilated calcining and chemical precipitation, respectively, to remove the residual carbon which is harmful to cement composites. The structures and morphologies of these products are investigated by the Fourier transform infrared spectroscopy, X-ray diffraction, scanning/ transmission electron microscopy and N2 adsorption- desorption analyzer. The results show that the as-produced RHA and Si02 nanoparticles exist in amorphous phase without residual carbon, and exhibit porous structures with specific surface areas of 170.19 and 248. 67 m2 /g , respectively. The micro particles of RHA are aggregated by numerous loosely packed Si02 gel particles with the diameter of 50 to 100 nm. The Si02 nanoparticles are well dispersed with the average size of about 30 nm. Both the RHA and Si02 nanoparticles can significantly reduce the conductivity of saturated Ca（OH）2 solution and increase the early strength of the cement composites. They also exhibit high pozzolanic activity, indicating that they can be used as ecological nano mineral admixtures.展开更多
Chinese mitten crab （Eriocheir sinensis） has higher commercial value as food source than any other species of Eriocheir in China. To evaluate the germplasm resources and characterize the genetic diversity and popula...Chinese mitten crab （Eriocheir sinensis） has higher commercial value as food source than any other species of Eriocheir in China. To evaluate the germplasm resources and characterize the genetic diversity and population structure of the crabs in different water systems, two stocks and two farming populations were assessed with 25 polymorphic microsallite loci available in public GenBank. Basic statistics showed that the average observed heterozygosity （Ho） amongst populations ranged from 0.5789 to 0.6824. However, a remarkable presence of inbreeding and heterozygote deficiencies were observed. To analyze population structure, pairwise FST coefficients explained only -10.3% variability from the subdivision of mitten crab populations, the remaining variability stems from the subdivision within subpopulations. Although the four populations had slight differentiation, different allelic frequencies resulted in distinct population structures. Two stocks and one farming population were clustered together to the phylogenetic branch of Yangtze crab, with an approximate membership of 95%. Whereas, another farming population was clustered singly to the phylogenetic branch of the Liaohe crab, with a membership of 97.1%. The tests for individual admixture showed that Yangtze crab had probably been contaminated with individuals from other water systems. Genetic relationships between populations also supported the conclusion that Yangtze crab and Liaohe crab had different gene pools in spite of the origins of the same species.展开更多
Objective To investigate oxidative DNA damage in pharmacy technicians preparing antineoplastic drugs at the PIVAS （Pharmacy Intravenous Admixture Service） in two Chinese hospitals. Methods Urinary 8-OHdG served as a...Objective To investigate oxidative DNA damage in pharmacy technicians preparing antineoplastic drugs at the PIVAS （Pharmacy Intravenous Admixture Service） in two Chinese hospitals. Methods Urinary 8-OHdG served as a biomarker. 5-Fluorouracil （5-FU） concentrations in air, masks and gloves were determined. The spill exposure of each PIVAS technician to antineoplastic drugs was investigated. Eighty subjects were divided into exposed group t, II, and control group I, II. Results 5-FU concentration ratios for gloves and masks in exposed group I were significantly higher than those in exposed group II （P〈0.05 or P〈0.01）. The average urinary 8-OHdG concentrations in exposed group I, control group I, exposed group II, and control group II were 24.69＋0.93, 20.68＋1.07, 20.57＋0.55, and 12.96_＋0.73 ng/mg Cr, respectively. Urinary 8-OHdG concentration in exposed group I was significantly higher than that in control group I or that in exposed group 11 （P〈0.02）. There was a significant correlation between urinary 8-OHdG concentrations and spill frequencies per technician （P〈0.01）. Conclusion There was detectable oxidative DNA damage in PIVAS technicians exposed to antineoplastic drugs. This oxidative DNA damage may be associated with their spill exposure experience and contamination of their personal protective equipment.展开更多
文摘The role of metakaolin in the properties of Portland cement hydrated with ground water and sea water was described by magnetic susceptibility study. Cement pastes containing 0wt%, 10wt%, 20wt% and 30wt% replacement of metakaolin and in a water/cement （W/C） ratio of 0.4 were prepared. The susceptibility at different hydration periods was determined by Faraday Curie balance and it was related to the changes in setting time and compressive strength of admixtured cement. Compared with sea water-treated cement paste, the magnetic susceptibility of ground water-treated cement paste is higher in value. The observed result shows that, irrespective of water, the magnetic susceptibility increases with increasing metakaolin percentage replacement level in cement.
文摘Purpose-The utilization of alkali-free accelerators,primarily based on aluminum sulfate,in shotcrete often leads to significant shrinkage and cracking,jeopardizing long-term durability.This study aims to mitigate this issue by investigating the efficacy of silica fume(SF)and fly ash(FA),individually and combined,in controlling the shrinkage deformation of shotcrete.Design/methodology/approach-Shotcrete mixtures were prepared with cement partially replaced by SF,FA,or their combination(SF-FA).Aluminum sulfate was used as an accelerator.The shrinkage behavior under sealed and dry conditions was monitored.The underlying mechanisms were elucidated through hardened airvoid analysis,mercury intrusion porosimetry(MIP),and internal humidity tracking.Findings-Contrary to some previous studies,both individual and combined incorporation of mineral admixtures reduced the 28-day shrinkage.The SF-FA composite exhibited the most substantial reduction(23.72%sealed,17.76%dry),followed by SF alone(18.11%sealed)and FA alone(11.35%sealed).Mechanism analysis revealed that the admixtures refined the pore structure,reduced the volume of harmful pores,and,crucially,optimized the air-void system by increasing the population of fine bubbles.This created an internal buffering effect that alleviates capillary stress.The synergistic effect in the SF-FA group is attributed to complementary pore-filling at dual scales.Originality/value-This work demonstrates that,within an aluminum sulfate-accelerated shotcrete system,silica fume can effectively reduce shrinkage when its pore-refining effect is counterbalanced by a welloptimized micro-bubble network.It provides the first comprehensive evidence of the synergistic shrinkagereducing mechanism of SF and FA in such systems,offering a practical strategy for mix design optimization to enhance the volume stability of shotcrete.
基金funded by the National Natural Science Foundation of China(32070576,31801040,and 32270667)Lantai Young Scholars Program of Chinese History Institute(2022LTQN602)+11 种基金the National Social Science Fund of China(19VJX074 and 21CKG022)Priority Research Program of the Chinese Academy of Sciences:Pan-Third Pole Environment Study for a Green Silk Road(Pan-TPE)(XDA2004010101)the National Key Research and Development Program(2023YFC3303701-02)the Natural Science Foundation of Fujian Province of China(2023J06013)the Science and Technology Commission of Shanghai Municipality(18490750300)the National Key Research and Development Program(2020YFE0201600)Shanghai Municipal Science and Technology Major Project(2017SHZDZX01)the Major Project of National Social Science Foundation of China granted to C.C.W.(21&ZD285),S.W.(20&ZD212),and D.L.(21&ZD237)Major Special Project of Philosophy and Social Sciences Research of the Ministry of Education(2022JZDZ023)Open Research Fund of State Key Laboratory of Genetic Engineering at Fudan University(SKLGE-2310)Open Research Fund of Forensic Genetics Key Laboratory of the Ministry of Public Security(2023FGKFKT07)European Research Council(ERC)grant(ERC-2019-ADG-883700-TRAM).
文摘China's Northern and Southern Dynasties period(3rd–6th centuries AD)marked a significant era of ethnic integration in northern China.However,previous ancient DNA studies have primarily focused on northern ethnic groups,with limited research on the genetic formation of the hereditary elite family,especially considering their abundant archaeological record and clear material identity.In this study,we obtain the ancient genome of a hereditary elite family,Gao Bin(高宾,503 AD–572 AD),at 0.6473-fold coverage with 475,132 single-nucleotide polymorphisms(SNPs)on the 1240k panel.His mitochondrial haplogroup belongs to Z4 and Y-haplogroup to O1a1a2b-F2444∗.The genetic profile of Gao Bin is most similar to that of the northern Han Chinese.He can be modeled as deriving all his ancestry from Late Neolithic to Iron Age Yellow River farmers without influence from Northeast Asia,Korea,or the Mongolian Plateau.Our study sheds light on the genetic formation of hereditary elite families in the context of the Southern and Northern Dynasties ethnic integration.
基金The National Natural Science Foundation of China(Grant No.72474013)the Beijing Health Technology Promotion Project(Grant No.BHTPP2024007)。
文摘This study investigated the factors contributing to intravenous admixture preparation errors(IAPEs)within Pharmacy Intravenous Admixture Services(PIVAS).A retrospective analysis was conducted on IAPEs documented in the PIVAS unit of a large multi-specialty hospital in China,which houses over 2000 beds,covering the period from January 1,2015 to December 31,2022.Drug preparation records were examined using a generalized linear mixed model(GLMM)to identify both univariate and multivariate factors associated with IAPE occurrences.A total of 824 IAPE cases were recorded during the study period,yielding an overall error rate of 0.018%.Univariate analysis identified drug categories(general drugs,anti-infective drugs,and antineoplastic drugs),preparation time(workdays),and years of work experience as significant determinants(P<0.05).Multivariate analysis further confirmed that drug categories(general and antineoplastic drugs),preparation time(workdays),and work experience remained statistically significant predictors of IAPE incidence(P<0.05).IAPEs in PIVAS were influenced by multiple factors,predominantly those related to personnel and drug characteristics.Targeted interventions,informed by multivariate analysis,are essential to mitigating these errors and enhancing medication safety.
基金Funded by the National Natural Science Foundation of China(Nos.51578412,51878479,52078372,and 52478272)the International Science and Technology Cooperation Project of the Key R&D Program of Science and Technology Innovation Yongjiang 2035(No.2024H023)。
文摘Four typical admixtures,polycarboxylate superplasticiser(PCE),tartaric acid(TA),sorbitol and polyacrylamide(PAM),were selected to systematically investigate their regulatory mechanisms on the formation of ettringite through Fourier transform infrared spectroscopy,X-ray diffraction,particle size analysis and nucleation kinetic model.The experimental results indicate that the admixtures alter the formation of ettringite through physical adsorption,complexation and solution viscosity modulation without changing its chemical structure.Low concentrations of PCE inhibit size growth by forming an adsorption layer on the surface of ettringite,whereas high concentrations of PCE alter the size change of ettringite by modulating the distribution of ionic concentrations.TA significantly reduces the size of ettringite by complexing Ca^(2+).Sorbitol and PAM promote the local growth of ettringite at low concentrations,leading to larger sizes.But at high concentrations,the size growth of ettringite is inhibited due to the increase in viscosity or the enhancement of complexation.Matlab nucleation kinetic modelling further shows that the addition of admixtures enhances the initial nucleation during ettringite synthesis,with values ranging from 14.45%to 114.25%.However,the subsequent nucleation rate of ettringite is significantly affected,decreasing by 12.79%to 71.74%.The results provide a theoretical basis for the design of ettringite materials and the optimisation of the application of admixtures.
文摘Crystalline admixtures(CA),also known as permeability reducer admixtures,are used in binder-based materials to improve concrete durability by reducing water permeability depth,increasing compressive strength,and stimulating crack healing.The purpose of this study is to evaluate the potential of crystalline admixtures to enhance the self-healing characteristics and durability attributes of concrete and to contribute to the understanding of their role in the design of long-term efficiency and sustainability.The 28 days specimens of M40 grade concrete were prepared by adding CA and cast as 150 mm cubes,25×25×285 mm prisms and disks with a diameter of 100 mm and height of 50 mm.All samples were then tested for compressive strength,water permeability,dry shrinkage,sodium sulfate attack test,Rapid Chloride Migration Test(RCMT),and rapid chloride penetration test(RCPT)to study the behavior of incorporating crystalline admixtures in concrete.The conclusion drawn from this study was that the addition of a crystalline admixture of 0.8%resulted in an increase in the compressive strength by 7.98%and a decrease in water penetration depth through the cube by 71.5%,while the dry shrinkage of the specimen incorporated with the crystalline admixture was 65.21%less than that of the specimen without the crystalline admixture.These results substantiate the beneficial role of CA in increasing the durability of concrete through increased strength,lower permeability,and better dimensional stability,thus making crystalline admixtures beneficial for incorporation into high-performance concrete applications.
基金Funded by the International Science and Technology Cooperation Project of the Key R&D Program of Science and Technology Innovation Yongjiang 2035。
文摘An evaluation method for self-healing capacity was designed,which includes the control of initial cracks and subsequent permeability testing.This method was employed to evaluate the self-healing behavior of mortars incorporating crystalline admixtures(CAs)under various conditions,including water immersion,limewater soaking,and wet-dry cycles,with varying CA dosages and crack widths.The experimental results indicate that cement possesses inherently self-healing capability.Limewater environments inhibits healing compared with water immersion;however,wet-dry cycles enhance the effectiveness of higher CA dosages.Increasing the CA content can not improve healing performance,and wide cracks(0.3 mm)substantially reduce the intrinsic self-healing potential of cement.
基金Hunan Provincial Department of Water Resources:Research on Formula Optimization and Performance Evaluation System of Ecological Concrete for River Water Quality Purification Based on the Dual Carbon Goal(Project No.:XSKJ2024064-44)。
文摘In this paper,the effects of four different mineral ginseng materials on the mechanical properties of mortar were studied,and the results showed that high territory,fly ash,and silica fume had an inhibitory effect on the drying shrinkage of mortar,and mineral powder increased the drying shrinkage of mortar.The high territory in the mineral admixture has the best effect on the inhibition of mortar drying shrinkage.The compressive strength and flexural strength of the mortar can be improved by adding a certain amount of mineral admixture,which increases the compressive strength by about 20%-40%and the flexural strength by about 20%-30%compared with the control group,and the improvement effect difference between different components is not large.
基金supported by grant klifW018 of the Bavarian State Ministry for Food,Agriculture and Forestry for funding.
文摘1.In recent years,climate change has led to drought and severe bark beetle infestations,affecting Norway spruce(Picea abies)across Europe,with detrimental consequences for forest owners,the forestry sector and associated industries.As a result,silviculture now faces the challenge of identifying tree species more resilient to these stressors to mitigate the impacts on forest management,forest-dependent economies and rural livelihoods.The North American Douglas-fir(Pseudotsuga menziesii)has emerged as a promising conifer species,better suited to future climate conditions and capable of producing high timber yields.2.Non-native tree species may affect native biodiversity,yet the impacts of Douglas-fir on native forest biodiversity are not clear.A comprehensive review evaluating the impact of Douglas-fir on faunal and floral biodiversity in European forests is lacking.3.Here,we present the results of a systematic literature review on Douglas-fir effects on native biodiversity,focusing on studies conducted in Europe.For arthropods,sufficient studies were found to do more detailed quantitative assessments.For fungi,birds,plants and soil fauna some studies existed,but only qualitative evaluations could be made.Other taxa were not investigated.4.In the present literature,the effects of Douglas-fir inclusion in stands on native biodiversity,compared to stands of solely native tree species,were mostly non-significant(78.6%,based on 32 studies).Positive effects were noted in 12%of cases,while negative effects were observed in 9.4%(total of 1,936 effects).Above-ground fauna was more extensively studied than below-ground fauna.Mechanisms proposed to explain taxa responses were often discussed but not always formally tested.For arthropods,there were varying effects on diversity between studies evaluating different scales(i.e.,tree-scale vs.stand-scale).In general,differences in effects depended on a range of factors,including stand composition and structure,season,and sampling site and period.5.Our review indicates limited evidence of adverse effects of Douglas-fir on biodiversity in European forests,highlighting a significant knowledge gap due to the scarcity of studies.Douglas-fir's impact on biodiversity likely varies depending on the forest type and management practices.Further research in diverse contexts is crucial to determine optimal levels of admixture and guide forest management.
基金supported by the National Natural Science Foundation of China(No.52179137).
文摘To mitigate the severe abrasion damage caused by high-velocity water flow in hydraulic engineering applications in Xizang, China, this study systematically optimized key mix design parameters, including aggregate gradation, sand ratio, fly ash content, and superplasticizer dosage. Based on the optimized mix, the combined effects of an abrasion-resistance enhancement admixture (AEA) and silica fume (SF) on the abrasion resistance of self-compacting concrete (SCC) were examined. The results demonstrated that the appropriate incorporation of AEA and SF significantly improved the abrasion resistance of SCC without compromising its workability. The proposed mix design not only achieves superior abrasion resistance but also provides practical guidance for the material design and engineering application of durable hydraulic concrete in harsh environments. Future research will focus on comprehensive durability assessments by simulating extreme hydraulic conditions, including sustained exposure to high-velocity sediment-laden flows, repeated freeze-thaw cycles, and corrosive salt spray environments, to thoroughly evaluate the long-term performance evolution of abrasion-resistant self-compacting concrete. Meanwhile, advanced microstructural analytical methods should be applied toelaborate the synergistic mechanisms of abrasion-resistance enhancement admixture (AEA), silica fume (SF), and steel fibers in altering the hydration product formation, optimizing the distribution of pore structure, and strengthening interfacial transition zones, to establish a solid scientific foundation for the development of high-performance composite materials.
文摘In the present study, we aimed to analyze the irrational medical orders and evaluate the effect of pharmacy intervention on pharmacy intravenous admixture services of outpatient and emergency departments in our hospital. The irrational medical orders of PIVAS at the outpatient and emergency departments were retrospectively analyzed in Jun. 2015. We strengthened the pharmacy intervention on irrational medical orders since July 2015. All the cases were selected by systematic sampling method. Cased studied in Jun. 2015 served as the control group, whereas those studied in Jan. 2016 served as the intervention group. The irrational rate and the irrational number of daily average were compared between the control group and intervention group. The common type of irrational outpatient and emergency intravenous orders mainly included irrational use of solvents, irrational dosing interval and inappropriate compatibility of drugs. The irrational rate was reduced from 17.4% to 3.3% （P〈0.01）, and the irrational number of daily average was decreased from 5.23 to 1.00 （P〈0.01）. Pharmacy intervention can reduce the irrational rate of medical orders in our hospital, which is of great significance to promote rational drug use and improve medical quality.
基金The Scholarship Supported by Ministry of Education of China for Research Abroad(No.3037[2006])the Excellent Doctoral Dissertation Foundation of Southeast University (No.YBTJ-0512)the National Basic Research Program of China(973Program)(No.2009CB623203)
文摘In order to investigate the effects of two mineral admixtures （i. e., fly ash and ground slag）on initial defects existing in concrete microstructures, a high-resolution X-ray micro-CT（ micro-focus computer tomography）is employed to quantitatively analyze the initial defects in four series of highperformance concrete （HPC）specimens with additions of different mineral admixtures. The nigh-resolution 3D images of microstructures and filtered defects are reconstructed by micro- CT software. The size distribution and volume fractions of initial defects are analyzed based on 3D and 2D micro-CT images. The analysis results are verified by experimental results of watersuction tests. The results show that the additions of mineral admixtures in concrete as cementitious materials greatly change the geometrical properties of the microstructures and the spatial features of defects by physical-chemistry actions of these mineral admixtures. This is the major cause of the differences between the mechanical behaviors of HPC with and without mineral admixtures when the water-to-binder ratio and the size distribution of aggregates are constant.
文摘In order to reduce the cohesive force between pavement and ice, the approach of pavement surface coating with hydrophobic admixtures is investigated. The deicing effect of this approach is examined by the contact angle test and the shear test. The durability of the approach is examined by the accelerated abrasion test, and the skid resistance of the pavement with surface coating is examined by the British pendulum test and the surface texture depth test. In the contact angle test, the contact angle between hydrophobic admixture and water is 100.2°. In the shear test, the maximum shear stress is 0.06 MPa for the specimen coated with hydrophobic admixture, which is much lower than that of the specimen without hydrophobic admixture coating, 3.5 MPa. Furth- ermore, the ice and asphalt surface are completely separated for the coated specimen while not for the uncoated specimen. Based on the accelerated abrasion test, the residual hydro- phobic admixture in the veins of the pavement after abrasion still has a deicing effect. From the skid resistance tests, the British pendulum number （BPN） and the texture depth （TD） of the specimen coated with hydrophobic admixtures are larger than those of the standard requirements. The overall experi-mental observation indicates that the approach can effectively reduce close contact between asphalt pavement and ice; therefore, it can be a promising solution to road icing problems in winter.
文摘The expansion and micro-cracks of the mortar with composite mineral admixtures （fly ash, zeolite and slag） due to the alkali-silica reaction （ASR） are studied. Results show that composite mineral admixtures cannot absolutely diminish the ASR of mortar bars with the low-alkali cement and a highly reactive aggregate. But the expansion rate and the deleterious expansion of the mortar bar are mostly reduced with increasing composite mineral admixture. The influence of mineral admixtures on the fluidity of the paste and the strength of the mortar is also studied.
基金The Key Program of the National Natural Science Foundation of China(No.51438003)the National Basic Research Program of China(973 Program)(No.2015CB655105)
文摘The rice husk ash （ RHA） and silica （ Si02） nanoparticles are prepared from rice husk charcoal （RHC） by the methods of ventilated calcining and chemical precipitation, respectively, to remove the residual carbon which is harmful to cement composites. The structures and morphologies of these products are investigated by the Fourier transform infrared spectroscopy, X-ray diffraction, scanning/ transmission electron microscopy and N2 adsorption- desorption analyzer. The results show that the as-produced RHA and Si02 nanoparticles exist in amorphous phase without residual carbon, and exhibit porous structures with specific surface areas of 170.19 and 248. 67 m2 /g , respectively. The micro particles of RHA are aggregated by numerous loosely packed Si02 gel particles with the diameter of 50 to 100 nm. The Si02 nanoparticles are well dispersed with the average size of about 30 nm. Both the RHA and Si02 nanoparticles can significantly reduce the conductivity of saturated Ca（OH）2 solution and increase the early strength of the cement composites. They also exhibit high pozzolanic activity, indicating that they can be used as ecological nano mineral admixtures.
文摘Chinese mitten crab （Eriocheir sinensis） has higher commercial value as food source than any other species of Eriocheir in China. To evaluate the germplasm resources and characterize the genetic diversity and population structure of the crabs in different water systems, two stocks and two farming populations were assessed with 25 polymorphic microsallite loci available in public GenBank. Basic statistics showed that the average observed heterozygosity （Ho） amongst populations ranged from 0.5789 to 0.6824. However, a remarkable presence of inbreeding and heterozygote deficiencies were observed. To analyze population structure, pairwise FST coefficients explained only -10.3% variability from the subdivision of mitten crab populations, the remaining variability stems from the subdivision within subpopulations. Although the four populations had slight differentiation, different allelic frequencies resulted in distinct population structures. Two stocks and one farming population were clustered together to the phylogenetic branch of Yangtze crab, with an approximate membership of 95%. Whereas, another farming population was clustered singly to the phylogenetic branch of the Liaohe crab, with a membership of 97.1%. The tests for individual admixture showed that Yangtze crab had probably been contaminated with individuals from other water systems. Genetic relationships between populations also supported the conclusion that Yangtze crab and Liaohe crab had different gene pools in spite of the origins of the same species.
基金supported by the Scientific Research Fund of Health Bureau in Zhejiang Province (2009A089)Scientific Research Fund of Education Bureau in Zhejiang Province (Y200804934)
文摘Objective To investigate oxidative DNA damage in pharmacy technicians preparing antineoplastic drugs at the PIVAS （Pharmacy Intravenous Admixture Service） in two Chinese hospitals. Methods Urinary 8-OHdG served as a biomarker. 5-Fluorouracil （5-FU） concentrations in air, masks and gloves were determined. The spill exposure of each PIVAS technician to antineoplastic drugs was investigated. Eighty subjects were divided into exposed group t, II, and control group I, II. Results 5-FU concentration ratios for gloves and masks in exposed group I were significantly higher than those in exposed group II （P〈0.05 or P〈0.01）. The average urinary 8-OHdG concentrations in exposed group I, control group I, exposed group II, and control group II were 24.69＋0.93, 20.68＋1.07, 20.57＋0.55, and 12.96_＋0.73 ng/mg Cr, respectively. Urinary 8-OHdG concentration in exposed group I was significantly higher than that in control group I or that in exposed group 11 （P〈0.02）. There was a significant correlation between urinary 8-OHdG concentrations and spill frequencies per technician （P〈0.01）. Conclusion There was detectable oxidative DNA damage in PIVAS technicians exposed to antineoplastic drugs. This oxidative DNA damage may be associated with their spill exposure experience and contamination of their personal protective equipment.
