Late Ordovician provenance and depositional setting in the southwestern Ordos Block, China: constraints from zircon U-Pb geochronology

Fu Yang,Gang Chen,Yu Kang,Dongmin Ma,Qilin Chen,Tian Tao,Fu Deliang 한국지질과학협의회 2020 Geosciences Journal Vol.24 No.2

The U-Pb ages of single zircon grains contained in the sandstone samples were analyzed by the LA-ICP-MS method, the sediment provenances and geological significance were discussed. The LA-ICP-MS zircon U-Pb dating from the sandstones, tuffaceous sandstones and volcanic tuffs of the Pingliang and Zhaolaoyu Formations along the southwestern Ordos Block are used to limit the maximum depositional age and material sources. The results show that: (1) The youngest ages of zircon dating in the three samples are 445 Ma, 444 Ma and 443 Ma, respectively, suggesting that the studied Formations were deposited in the Late Ordovician. (2) The detrital zircon U-Pb age analysis of the sandstones sample from the Pinliang Formation clustered in the 445–477 Ma, 588–1548 Ma and 1612–2496 Ma with the corresponding youngest peak age of 454.5 ± 3.3 Ma. (3) The distribution of zircon U-Pb age in sandstone samples showing that the sedimentary rocks detritus was mainly sourced from the North Qinling-Qilian terranes and the NCC, and has double provenance supply in the north and south. The material source of the tuffaceous sandstones and volcanic tuffs mainly comes from the volcanic and magmatic activity related to the North Qilian-North Qinling Island Arcs.

Energy analysis of the deformation and failure process of sandstone and damage constitutive model

Tao Wen,Huiming Tang,Junwei Ma,Junwei Ma 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.2

The damage theory was introduced to clarify and simulate the strain softening property of rocks. On the basis of the theory, an energy method was utilized to portray the rock mechanical properties from microscopic perspective. Firstly, from the perspective of rock microstructure, damage variable (expressed as D) was redefined by dividing the rock into three portions: undamaged materials, damaged materials and micro-defects, and an impact factor was introduced as the connection between the damaged material and the micro-defects. Meanwhile, the method for determining the impact factor was presented. Secondly, the damage variable was redefined in light of energy dissipation, then damage evolution analysis was conducted based on triaxial tests. An improved rock damage constitutive model was further obtained in another expression to reflect the energy change law. Subsequently, the relationship between D and the deformation and failure process of rocks was analyzed on account of the damage evolution equation formularized by fitting to a logistic function, which can measure the influence of energy dissipation on the propagation of micro-defects. By comparing between experimental results and theoretical results of illustrative examples, the effectiveness of the improved model was validated, and the its application was also discussed.

Prediction of methane emission from sheep based on data measured in vivo from open-circuit respiratory studies

Tao Ma,Kaidong Deng,Qiyu Diao 아세아·태평양축산학회 2019 Animal Bioscience Vol.32 No.9

Objective: The current study analysed the relationships between methane (CH4) output from animal and dietary factors. Methods: The dataset was obtained from 159 Dorper×thin-tailed Han lambs from our seven studies, and CH4 production and energy metabolism data were measured in vivo by an open-circuit respiratory method. All lambs were confined indoors and fed pelleted diet during the whole experimental period in all studies. Data from two-thirds of lambs were used to develop linear and multiple regressions to describe the relationship between CH4 emission and dietary variables, and data from the remaining one third of lambs were used to validate the established models. Results: CH4 emission (g/d) was positively related to dry matter intake (DMI) and gross energy intake (GEI) (p<0.001). CH4 energy/GEI was negatively related to metabolizable energy/gross energy and metabolizable energy/digestible energy (p<0.001). Using DMI to predict CH4 emission (g/d) resulted in a coefficient of determination (R2) of 0.80. Using GEI, digestible energy intake, and metabolizable energy intake predict CH4 energy/GEI resulted in a R2 of 0.92. Conclusion: the prediction equations established in the current study are useful to develop appropriate feeding and management strategies to mitigate CH4 emissions from sheep.

Effect of Dietary Concentrate:forage Ratios and Undegraded Dietary Protein on Nitrogen Balance and Urinary Excretion of Purine Derivatives in Dorper×thin-tailed Han Crossbred Lambs

Ma, Tao,Deng, Kai-Dong,Tu, Yan,Jiang, Cheng-Gang,Zhang, Nai-Feng,Li, Yan-Ling,Si, Bing-Wen,Lou, Can,Diao, Qi-Yu Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.2

This study aimed to investigate dietary concentrate:forage ratios (C:F) and undegraded dietary protein (UDP) on nitrogen balance and urinary excretion of purine derivatives (PD) in lambs. Four Dorper${\times}$thin-tailed Han crossbred castrated lambs with $62.3{\pm}1.9$ kg body weight at 10 months of age were randomly assigned to four dietary treatments in a $2{\times}2$ factorial arrangement of two levels of C:F (40:60 and 60:40) and two levels of UDP (35% and 50% of CP), according to a complete $4{\times}4$ Latin-square design. Each experimental period lasted for 19 d. After a 7-d adaptation period, lambs were moved into individual metabolism crates for 12 d including 7 d of adaption and 5 d of metabolism trial. During the metabolism trial, total urine was collected for 24 h and spot urine samples were also collected at different times. Urinary PD was measured using a colorimetric method and creatinine was measured using an automated analyzer. Intake of dry matter (DM) (p<0.01) and organic matter (OM) (p<0.01) increased as the level of UDP decreased. Fecal N was not affected by dietary treatment (p>0.05) while urinary N increased as the level of UDP decreased (p<0.05), but decreased as dietary C:F increased (p<0.05). Nitrogen retention increased as dietary C:F increased (p<0.05). As dietary C:F increased, urinary excretion of PD increased (p<0.05), but was not affected by dietary UDP (p>0.05) or interaction between dietary treatments (p>0.05). Daily excretion of creatinine was not affected by dietary treatments (p<0.05), with an average value of $0.334{\times}0.005$ mmol/kg $BW^{0.75}$. A linear correlation was found between total PD excretion and PDC index ($R^2$ = 0.93). Concentrations of creatinine and PDC index in spot urine were unaffected by sampling time (p>0.05) and a good correlation was found between the PDC index (average value of three times) of spot urine and daily excretion of PD ($R^2$ = 0.88). These results suggest that for animals fed ad libitum, the PDC index in spot urine is effective to predict daily excretion of PD. In order to improve the accuracy of the spot sampling technique, an appropriate lag phase between the time of feeding and sampling should be determined so that the sampling time can coincide with the peak concentration of PD in the urine.

Characteristics of Desulfurized Rubber Asphalt and Mixture

Tao Ma,Yongli Zhao,Xiaoming Huang,Yao Zhang 대한토목학회 2016 KSCE JOURNAL OF CIVIL ENGINEERING Vol.20 No.4

This paper investigated the modification mechanism of the desulfurized rubber asphalt, and compared its performances with those of crumb rubber asphalt. The microstructures of desulfurized rubber asphalt and crumb rubber asphalt were identified by using the scanning electron microscope technology, component analysis and infrared spectrum analysis. Conventional and Strategic Highway Research Program (SHRP) performance tests were conducted to evaluate the performances of desulfurized rubber asphalt and crumb rubber asphalt. Mixture performance tests were also performed to characterize the high temperature rutting resistance, low temperature cracking resistance, moisture stability and fatigue life of the desulfurized rubber asphalt mixture and crumb rubber asphalt mixture. It was found that the modification mechanisms of desulfurized rubber asphalt and crumb rubber asphalt are different. The desulfurized rubber can integrate into the asphalt while the crumb rubber mainly exists incompatibly in asphalt. This difference results in the various performances between the desulfurized rubber asphalt and crumb rubber asphalt. Both crumb rubber and desulfurized rubber can improve the performance of asphalt binder and mixture, but the desulfurized rubber asphalt has much lower viscosity and better storage stability than the crumb rubber asphalt. The preparing temperature of the desulfurized rubber asphalt mixture can be reduced by 10~20°C compared to the crumb rubber asphalt mixture. Moreover, without the interference of solid rubber particles, the desulfurized rubber asphalt can be used in dense-graded asphalt mixture while crumb rubber asphalt mixture tends to use gap gradation with high asphalt content.

Doping palladium with tellurium for the highly selective electrocatalytic reduction of aqueous CO ₂ to CO

Tao, Hengcong,Sun, Xiaofu,Back, Seoin,Han, Zishan,Zhu, Qinggong,Robertson, Alex ,W.,Ma, Tao,Fan, Qun,Han, Buxing,Jung, Yousung,Sun, Zhenyu Royal Society of Chemistry 2018 Chemical Science Vol.9 No.2

<▼1><P>The doping of Pd with a small amount of Te can selectively convert CO<SUB>2</SUB> to CO with a low overpotential.</P></▼1><▼2><P>Designing highly selective and energy-efficient electrocatalysts to minimize the competitive hydrogen evolution reaction in the electrochemical reduction of aqueous CO<SUB>2</SUB> remains a challenge. In this study, we report that doping Pd with a small amount of Te could selectively convert CO<SUB>2</SUB> to CO with a low overpotential. The PdTe/few-layer graphene (FLG) catalyst with a Pd/Te molar ratio of 1 : 0.05 displayed a maximum CO faradaic efficiency of about 90% at –0.8 V (<I>vs.</I> a reversible hydrogen electrode, RHE), CO partial current density of 4.4 mA cm<SUP>–2</SUP>, and CO formation turnover frequency of 0.14 s<SUP>–1</SUP> at –1.0 V (<I>vs.</I> a RHE), which were 3.7-, 4.3-, and 10-fold higher than those of a Pd/FLG catalyst, respectively. Density functional calculations showed that Te adatoms preferentially bind at the terrace sites of Pd, thereby suppressing undesired hydrogen evolution, whereas CO<SUB>2</SUB> adsorption and activation occurred on the high index sites of Pd to produce CO.</P></▼2>

A Novel In Situ Gel Formulation of Ranitidine for Oral Sustained Delivery

( Tao Ma ),( Hao Ping Xu ),( Min Shi ),( Jin Ling Jiang ) 한국응용약물학회 2014 Biomolecules & Therapeutics(구 응용약물학회지) Vol.22 No.2

The main purpose of this study was to develop a novel, in situ gel system for sustained delivery of ranitidine hydrochloride. Ranitidinein situ gels at 0.2%, 0.5%, and 1.0% gellan gum concentration (w/v) were prepared, respectively, and characterized in termsof preparation, viscosity and in vitro release. The viscosity of the gellan gum formulations in solution increased with increasingconcentrations of gellan gum. In vitro study showed that the release of ranitidine from these gels was characterized by an initialphase of high release (burst effect) and translated to the second phase of moderate release. Single photon emission computingtomography technique was used to evaluate the stomach residence time of gel containing 99mTc tracer. The animal experimentsuggested in situ gel had feasibility of forming gels in stomach and sustained the ranitidine release from the gels over the periodof at least 8 h. In conclusion, the in situ gel system is a promising approach for the oral delivery of ranitidine for the therapeuticeffects improvement.

Radiological gastrostomy: A comparative analysis of different image-guided methods

Hong-Tao Hu,Hang Yuan,Chen-Yang Guo,Quan-Jun Yao,Xiang Geng,Hong-Tao Cheng,Jun-Li Ma,Yan Zhao,Li Jiang,Yu-Qing Zhao,Hai-Liang Li 소화기인터벤션의학회 2021 International journal of gastrointestinal interven Vol.10 No.2

Background: Radiographic guided percutaneous gastrostomy has become a safe and effective enteral nutrition method for patients who can not eat by mouth. Fluoroscopy, computed tomography (CT) and cone-beam CT have been routinely used clinically. The aim of this study was to compare the advantages and disadvantages of percutaneous gastrostomy using different radiographic guided methods. Methods: We retrospectively analyzed the clinical data of 538 patients undergoing percutaneous gastrostomy in our department. According to the image guidance method used in gastrostomy, the patients were divided into groups A by fluoroscopy guidance, group B by fluoroscopy combined with C-arm CT guidance, and group C with the whole process CT guidance. The gastrostomy success rate, complication rate, procedure time, and patient radiation dose were analyzed in the three groups. Results: Among 538 patients, 534 were successful and the success rates are 94.3%, 99.3%, and 100% in group A, B, and C, respectively (P > 0.05). There were 3 cases occurred postoperative bleeding as serious adverse events and transferred to surgical gastrostomy. The minor complications include local infection, hyperplasia of granulation tissue, tube obstruction or prolapse, and local pain of the ostomy. The minor complication rates were 10.5%, 10.4%, and 7.7% in group A, B, and C, respectively (P > 0.05). The average procedure time was 25.57 ± 5.99 minutes, 29.01 ± 6.63 minutes, and 45.47 ± 8.98 minutes, respectively (χ2 = 87.98, P < 0.001). The average radiation dosage was 27.30 ± 19.27 mGy, 145.07 ± 106.08 mGy, and 2,590.26 ± 1,088.22 mGy, respectively (χ2 = 204.44, P < 0.001). Conclusion: There were no significant differences in the success rates and complication rates of gastrostomy under the three guiding methods. For difficult cases, CT-guided gastrostomy may be a very useful supplemental method.

청소년이 지각한 그릿, 협동심, 학업무기력, 삶의 만족도 간 구조분석

마언타오 ( Ma En Tao ),김춘경 ( Kim Choon Kyung ) 한국정서행동장애학회 2021 정서ㆍ행동장애연구 Vol.37 No.4

본 연구의 목적은 청소년의 그릿, 협동심, 학업무기력이 삶의 만족도에 미치는 직접 영향력을 밝혀, 청소년의 삶의 만족도를 높이기 위한 방법을 모색하는 데 있다. 연구대상은 ‘한국아동·청소년패널조사(KCYPS) 2018’의 중학교 1학년 패널의 2차년도(2019) 자료를 통해 수집된 2,590명이다. 자료는 IBM SPSS 25 프로그램과 AMOS 18 프로그램을 이용하여 분석하였다. 연구결과는 다음과 같다. 첫째, 청소년의 그릿과 협동심, 학업무기력은 삶의 만족도에 직접적인 영향을 미치는 것으로 나타났다. 둘째, 청소년의 그릿과 협동심은 학업무기력에 직접적인 영향을 미치는 것으로 나타났다. 셋째, 청소년의 그릿은 협동심에 직접적인 영향을 미치는 것으로 나타났다. 마지막, 청소년의 삶의 만족도 향상을 위한 개입의 방향성과 후속 연구를 위한 제언을 제시하였다. The purpose of this study is to find ways to increase adolescents satisfaction with life by revealing the direct influence of adolescents grit, cooperation and academic helplessness on satisfaction with life. The participants were 2,590 middle school students from second wave (2019) of the ‘Korean Children and Youth Panel Survey 2018’. The data were analyzed using IBM SPSS 25 and AMOS 18 program. The results of this study are as follows. First, the grit and cooperation, academic helplessness of adolescents directly affects their satisfaction with life. Second, the grit and cooperation of adolescents directly affect their academic helplessness. Thirdly, the grit of adolescents directly affect their cooperation. Lastly, these results implicated intervention tactics for satisfaction with life and suggested possible future research.

Radiological gastrostomy: A comparative analysis of different image-guided methods

Hong-Tao Hu,Hang Yuan,Chen-Yang Guo,Quan-Jun Yao,Xiang Geng,Hong-Tao Cheng,Jun-Li Ma,Yan Zhao,Li Jiang,Yu-Qing Zhao,Hai-Liang Li 소화기인터벤션의학회 2021 Gastrointestinal Intervention Vol.10 No.2

Background: Radiographic guided percutaneous gastrostomy has become a safe and effective enteral nutrition method for patients who can not eat by mouth. Fluoroscopy, computed tomography (CT) and cone-beam CT have been routinely used clinically. The aim of this study was to compare the advantages and disadvantages of percutaneous gastrostomy using different radiographic guided methods. Methods: We retrospectively analyzed the clinical data of 538 patients undergoing percutaneous gastrostomy in our department. According to the image guidance method used in gastrostomy, the patients were divided into groups A by fluoroscopy guidance, group B by fluoroscopy combined with C-arm CT guidance, and group C with the whole process CT guidance. The gastrostomy success rate, complication rate, procedure time, and patient radiation dose were analyzed in the three groups. Results: Among 538 patients, 534 were successful and the success rates are 94.3%, 99.3%, and 100% in group A, B, and C, respectively (P > 0.05). There were 3 cases occurred postoperative bleeding as serious adverse events and transferred to surgical gastrostomy. The minor complications include local infection, hyperplasia of granulation tissue, tube obstruction or prolapse, and local pain of the ostomy. The minor complication rates were 10.5%, 10.4%, and 7.7% in group A, B, and C, respectively (P > 0.05). The average procedure time was 25.57 ± 5.99 minutes, 29.01 ± 6.63 minutes, and 45.47 ± 8.98 minutes, respectively (χ2 = 87.98, P < 0.001). The average radiation dosage was 27.30 ± 19.27 mGy, 145.07 ± 106.08 mGy, and 2,590.26 ± 1,088.22 mGy, respectively (χ2 = 204.44, P < 0.001). Conclusion: There were no significant differences in the success rates and complication rates of gastrostomy under the three guiding methods. For difficult cases, CT-guided gastrostomy may be a very useful supplemental method.