444 results on '"Feng, Tian"'
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2. Clinical Efficacy of Posteromedial Approaches for Haraguchi Type II Fracture.
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Feng Tian, Rui Xia, Lei Liu, Shiyuan Fang, and Wei Xu
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POSTEROLATERAL corner , *WOUNDS & injuries , *SPRAINS , *PROLAPSE of bodily organs , *NERVOUS system injuries - Abstract
Objective • This study was to analyze and compare the clinical efficacy of open reduction and internal fixation through posterolateral and the posterior medial approach to treat Haraguchi Type II posterior malleolar fracture. Methods • The clinical data of 91 patients with trimalleolar fractures sent to our hospital from January 2018 to January 2020 were analyzed. All of the patients were the result of traumatic injuries, such as sprains or car accidents. All patients were treated with open reduction and internal fixation and divided into control group and observation group according to different surgical approaches. Forty-five cases were treated with the posterolateral approach(control group) and forty-six cases treated with the posteriormedial approach(observation group) . The operation status of the two groups (operating time, intraoperative blood loss, postoperative drainage, and hospital stay), postoperative status (visual analogue scale (VAS) before the operation, 1d, 3d and 7d after operation), the score of patient’s American orthopedic foot and ankle society (AOFAS) at the time of discharge, fracture healing time and full weight-bearing time), efficacy and safety were recorded. Results • All cases underwent surgery, with no significant difference in the time from fracture to surgery between the control and observation groups (P > .05). Compared to the control group, the operating time, intraoperative blood loss, postoperative drainage, and hospital stay in the observation group were significantly reduced (P < .05). One day after the operation, no significant difference was shown in VAS between 2 groups (P > .05), while AOFAS score in the observation group was significantly increased (P < .05). Three and 7 days after the operation, VAS, fracture healing time, and full weight-bearing time were significantly decreased in both groups (P < .05). In the control group, the cases with excellent, good, fair, and poor efficacy were 26, 8, 5, 6, with an acceptable rate of 86.67% (39/45). In the observation group, the cases with excellent, good, fair, and poor efficacy were 29, 10, 5, and 2, with an acceptable rate of 95.65% (44/46). There was no significant difference in efficacy between the 2 groups (P > .05). During the follow-up time of 12~27 months (the median time of 18.5 months), all patients showed first-stage grade A healing, and osseous union with good fixation position and no fracture, deformation, loosening or prolapse, and no sural nerve injury or incision infection occurred. Conclusion • Both the posterolateral approach and posterior medial approach open reduction and internal fixation can be used to treat Haraguchi type II posterior malleolus fractures, with good efficacy and safety. The posterior medial approach showed faster recovery and less damage than the posterolateral approach. Overall, the posterolateral approach is more dominant in the treatment of Haraguchi Type II posterior malleolar fracture. [ABSTRACT FROM AUTHOR]
- Published
- 2024
3. INTERNET OF THINGS TEMPERATURE CONTROL OF INDIRECT DUAL TANK HEAT STORAGE SYSTEM IN SOLAR PHOTO-THERMAL POWER PLANT.
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Feng TIAN
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SOLAR heating , *SOLAR power plants , *SOLAR thermal energy , *TEMPERATURE control , *STORAGE tanks , *HEAT storage , *SOLAR technology - Abstract
In order to study the temperature control of the IoT for indirect dual tank heat storage systems in solar thermal power plants, the author proposes a refined design method for heat storage systems. Through CFD software FLUENT analysis, the author proposes a temperature control scheme for storage tanks in solar thermal power plants and applies this method to the temperature control and salt injection processes of actual commercial power plants. The refined design of a systematic heat storage system mainly involves precise calculation of molten salt content and refined analysis of overall and local stresses in the storage tank. For molten salt storage tanks with a diameter of about 30 m, every 1 cm of liquid level design error will result in economic losses of tens of thousands of Yuan. In addition, the design process of storage tanks should fully consider temperature control, salt injection, and some special operating conditions during operation. By numerically simulating the flow process of flue gas and molten salt in the storage tank and the real-time wall temperature of the storage tank, a temperature control scheme that does not exceed the maximum allowable wall temperature difference of the storage tank is obtained to reduce thermal stress during the temperature control process of the storage tank, reduce the risk and failure rate of the storage tank. The temperature control scheme has achieved good results in practical projects. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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4. Visual search strategies of performance monitoring used in action anticipation of basketball players.
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Li, Yawei, Feng, Tian, Zhang, Fuchun, Asgher, Umer, Yan, Bingbing, and Peng, Tianyu
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VISUAL perception , *GAZE , *BASKETBALL players , *BASKETBALL player recruiting , *EXPECTATION (Psychology) , *ELITE athletes - Abstract
Introduction: Numerous studies have found that expert players anticipate better than novices. If more accurate prediction represents performance monitoring of experts, what are the advantages of elite basketball players in identifying and processing available cues? There is still a lack of sufficient evidence. This study examined the visual search in basketball players and explored the performance monitoring of action anticipation, adopting an expert–novice paradigm and eye‐movement technology. Methods: Forty basketball players were recruited in this study: 20 in the expert group and 20 in the novice group. Participants were asked to predict the outcome of videotaped basketball throws and their accuracy and eye‐movement characteristics were record. Results: The accuracy of the expert was significantly higher than that of the novice. The experts were able to instantly search and identify important cues in anticipation, and the gaze area of the experts was concentrated on the area of interest of the body. Additionally, the expert group showed long, repetitive, and rapid visual search of vital information, and improved their performance of the task. Conclusion: The experts could monitor the performance of prediction by grabbing vital shooting information (such as the body of a player). The results suggest the athletes and coaches that if they want to improve the ability of prediction, it may be useful to shift their focus of attention from ball trajectory to body action. [ABSTRACT FROM AUTHOR]
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- 2023
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5. Organo‐Mediator Enabled Electrochemical Deuteration of Styrenes.
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Yang, Keming, Feng, Tian, and Qiu, Youai
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DEUTERATION , *DEUTERIUM oxide , *STYRENE , *RADIOLABELING ,CHEMICAL labeling - Abstract
Despite widespread use of the deuterium isotope effect, selective deuterium labeling of chemical molecules remains a major challenge. Herein, a facile and general electrochemically driven, organic mediator enabled deuteration of styrenes with deuterium oxide (D2O) as the economical deuterium source was reported. Importantly, this transformation could be suitable for various electron rich styrenes mediated by triphenylphosphine (TPP). The reaction proceeded under mild conditions without transition‐metal catalysts, affording the desired products in good yields with excellent D‐incorporation (D‐inc, up to >99 %). Mechanistic investigations by means of isotope labeling experiments and cyclic voltammetry tests provided sufficient support for this transformation. Notably, this method proved to be a powerful tool for late‐stage deuteration of biorelevant compounds. [ABSTRACT FROM AUTHOR]
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- 2023
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6. Organo‐Mediator Enabled Electrochemical Deuteration of Styrenes.
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Yang, Keming, Feng, Tian, and Qiu, Youai
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DEUTERATION , *DEUTERIUM oxide , *STYRENE , *RADIOLABELING ,CHEMICAL labeling - Abstract
Despite widespread use of the deuterium isotope effect, selective deuterium labeling of chemical molecules remains a major challenge. Herein, a facile and general electrochemically driven, organic mediator enabled deuteration of styrenes with deuterium oxide (D2O) as the economical deuterium source was reported. Importantly, this transformation could be suitable for various electron rich styrenes mediated by triphenylphosphine (TPP). The reaction proceeded under mild conditions without transition‐metal catalysts, affording the desired products in good yields with excellent D‐incorporation (D‐inc, up to >99 %). Mechanistic investigations by means of isotope labeling experiments and cyclic voltammetry tests provided sufficient support for this transformation. Notably, this method proved to be a powerful tool for late‐stage deuteration of biorelevant compounds. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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7. Prebiotic Syntheses of Organophosphorus Compounds from Reduced Source of Phosphorus in Non-Aqueous Solvents.
- Author
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Gull, Maheen, Feng, Tian, Smith, Benjamin, Calcul, Laurent, and Pasek, Matthew A.
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NONAQUEOUS solvents , *ORGANOPHOSPHORUS compounds , *CHOLINE chloride , *AMMONIUM compounds , *DISSOLUTION (Chemistry) , *INORGANIC compounds , *ALCOHOL oxidation , *SOLVENTS - Abstract
Reduced-oxidation-state phosphorus (reduced P, hereafter) compounds were likely available on the early Earth via meteorites or through various geologic processes. Due to their reactivity and high solubility, these compounds could have played a significant role in the origin of various organophosphorus compounds of biochemical significance. In the present work, we study the reactions between reduced P compounds and their oxidation products, with the three nucleosides (uridine, adenosine, and cytidine), with organic alcohols (glycerol and ethanolamine), and with the tertiary ammonium organic compound, choline chloride. These reactions were studied in the non-aqueous solvent formamide and in a semi-aqueous solvent comprised of urea: ammonium formate: water (UAFW, hereafter) at temperatures of 55–68 °C. The inorganic P compounds generated through Fenton chemistry readily dissolve in the non-aqueous and semi-aqueous solvents and react with organics to form organophosphites and organophosphates, including those which are identified as phosphate diesters. This dual approach (1) use of non-aqueous and semi-aqueous solvents and (2) use of a reactive inorganic P source to promote phosphorylation and phosphonylation reactions of organics readily promoted anhydrous chemistry and condensation reactions, without requiring any additive, catalyst, or other promoting agent under mild heating conditions. We also present a comparative study of the release of P from various prebiotically relevant phosphate minerals and phosphite salts (e.g., vivianite, apatite, and phosphites of iron and calcium) into formamide and UAFW. These results have direct implications for the origin of biological P compounds from non-aqueous solvents of prebiotic provenance. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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8. Fast formation of a black inner α‐Al2O3 layer doped with CuO on Al–Cu–Li alloy by soft sparking PEO process.
- Author
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He, Xiaorui, Feng, Tian, Cheng, Yulin, Hu, Panfeng, Le, Zhengzhou, Liu, Zihua, and Cheng, Yingliang
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COPPER oxide , *ELECTROLYTIC oxidation , *PLASMA flow , *THERMAL conductivity , *CRISTOBALITE , *DILUTE alloys , *AMORPHOUS alloys , *HEAT resistant alloys - Abstract
Forming high‐temperature α‐Al2O3 phase under soft sparking is an intriguing phenomenon in plasma electrolytic oxidation (PEO) of Al alloys, which contradicts the low energy input of the process. In this study, α‐Al2O3 doped with black CuO is formed beneath an amorphous white outer layer on Al–Cu–Li alloy by PEO in a dilute silicate electrolyte under soft sparking. In comparison, reddish coatings with dominating γ‐Al2O3 are formed under the conventional plasma discharges, although blackish inner layer with α‐Al2O3 can also be exposed by heavily polishing the samples. In order to know the underlying mechanism, temperatures at the coating surface and the underlying substrate have been monitored by a thermocouple under the conventional and soft sparking PEO regimes, respectively. Interestingly, high temperatures are detected in the case of soft sparking rather than PEO with strong discharges. The formation of CuO, quartz, and cristobalite within the soft sparking coating also supports the existence of high temperature. Hence, the formation of α‐Al2O3 under soft sparking can be resolved to the conventional thermal activation mechanism, without the need of seeking other plausible explanations. Thermal condition evaluation for soft sparking PEO suggests that values of the effective thermal conductivity during PEO process for the outer layer and the barrier layer at the coating/substrate interface might be lower than ∼0.05 and ∼0.0017 W m−1 K−1, respectively. It is believed that the amorphous structure of the outer and barrier layers effectively blocks the heat dissipation, facilitating the formation of a highly wear‐resistant inner layer with α‐Al2O3, CuO, and the other high‐temperature species under soft sparking. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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9. On Hom-groups and Hom-group Actions.
- Author
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Chen, Liang Yun, Feng, Tian Qi, Ma, Yao, Saha, Ripan, and Zhang, Hong Yi
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ISOMORPHISM (Mathematics) , *GENERALIZATION - Abstract
A Hom-group is the non-associative generalization of a group whose associativity and unitality are twisted by a compatible bijective map. In this paper, we give some new examples of Hom-groups, and show the first, second and third isomorphism theorems of Hom-groups. We also introduce the notion of Hom-group action, and as an application, we prove the first Sylow theorem for Hom-groups along the line of group actions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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10. Impact of urban spatial structure elements on carbon emissions efficiency in growing megacities: the case of Chengdu.
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Feng, Tian and Zhou, Bo
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CARBON emissions , *SUSTAINABLE urban development , *MEGALOPOLIS , *URBAN density , *URBAN planning , *MOUNTAIN forests - Abstract
Quantitative research on the impact weight and impact of regional heterogeneity of urban spatial structure elements on carbon emissions efficiency can provide a scientific basis and practical guidance for low-carbon and sustainable urban development. This study uses the megacity of Chengdu as an example to measure and analyze the spatial carbon emission efficiency and multidimensional spatial structure elements by building a high-resolution grid and identifying the main spatial structure elements that affect urban carbon emissions and their impact weights via the Ordinary Least Squares regression (OLS) and Geographically Weighted Regression (GWR). The spatial heterogeneity of the impact of each element is also explored. The results show that the overall carbon emission efficiency of Chengdu is high in the center and low on the sides, which is related to urban density, functional mix, land use, and traffic structure. However, the influence of each spatial structure element is different in the developed central areas, developing areas of the plain, mountainous developing areas, underdeveloped areas of the plain, and mountainous underdeveloped areas. Thus, it is appropriate to form differentiated urban planning strategies based on the characteristics of the development of each zone. The findings provide inspiration and a scientific basis for formulating policies and practice to the future low-carbon development of Chengdu, while provide a reference for other growing megacities. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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11. A Twenty-Year Assessment of Spatiotemporal Variation of Surface Temperature in the Yangtze River Delta, China.
- Author
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Zhang, Quan, Feng, Tian, Wang, Mengen, Yang, Gang, Lu, Huimin, and Sun, Weiwei
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LAND surface temperature , *SURFACE temperature , *TREND analysis , *CITIES & towns , *CLIMATE change - Abstract
A good understanding of the processes of land surface temperature (LST) change is important for assessing regional climate change. In the present study, we obtained the MODIS MOD11A2 LST products over the Yangtze River Delta (YRD) from 2001 to 2020. In order to comprehensively assess the spatial and temporal variability of LST in the YRD region over the past two decades, the Theil–Sen Median trend analysis and Mann–Kendall test, BFAST01 trend decomposition, and landscape pattern analysis were used in this study. We show that the rate of linear change in LST in the YRD ranges from −0.019 °C/month to 0.046 °C/month. The BFAST01 trend decomposition identifies more details of LST change and monotonic increases, reversal increase, and interruption increase are the main warming trends. The distribution of the different trend types shows strong aggregation with high spatial heterogeneity. The LST breakpoints are mainly located in the northern and southern YRD, which frequently occurred during 2010–2013. Of the various land types, breakpoints occur most frequently in cropland and high NDVI (0.5–0.7) areas, and the intensity of most of them is within 2 °C. In addition, much stronger warming occurs in urban areas than in other land types. Our study provides a better understanding of the dynamics of LST in the YRD region over the past 20 years and highlights that breakpoints cannot be circumvented in regional temperature assessment. [ABSTRACT FROM AUTHOR]
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- 2023
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12. The degenerate hyperbolic problem for the two‐dimensional nonlinear wave system.
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Xiao, Wei and Feng, Tian
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NONLINEAR waves , *NONLINEAR systems , *NONLINEAR equations , *DEGENERATE differential equations , *BOUNDARY value problems , *METRIC spaces - Abstract
This paper constructs a local classical solution of degenerate hyperbolic problem for the two‐dimensional nonlinear wave system. To deal with the parabolic degeneracy, we introduce a new set of coordinates to transform the nonlinear wave system to a new system that has explicitly singularity‐regularity structures. By constructing a weighted metric space, we establish the existence of solution for the new system. Returning the solution to the original variables, we obtain the existence of the classical solution for the nonlinear wave system with degenerate boundary value problem. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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13. Electrochemical dual α,β-C(sp3)–H functionalization of cyclic N-aryl amines.
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Feng, Tian, Zhu, Zile, Zhang, Dongmei, Wang, Siyi, Li, Ruopu, Zhu, Zhaolin, Zhang, Xinxing, and Qiu, Youai
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DENSITY functional theory , *CHEMOSELECTIVITY , *CYCLIC voltammetry , *AMINES , *MASS spectrometry , *IRON - Abstract
Herein, a straightforward and efficient route for the construction of dual α,β-C(sp3)–H functionalized cyclic N-aryl amines using a combination of electrocatalysis and iron catalysis is disclosed. This method is achieved by multiple single electron oxidations and is carried out in an operationally simple manner with high chemo- and site-selectivity, setting the stage for the challenging multiple site selective C–H functionalization. The mechanism is supported by a variety of experimental probes and theoretical investigations, including cyclic voltammetry tests, a bipolar ultramicroelectrode (BUME) methodology combined with nano-electrospray ionization mass spectrometry, and density functional theory calculations. [ABSTRACT FROM AUTHOR]
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- 2023
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14. Prebiotic Chemistry of Phosphite: Mild Thermal Routes to Form Condensed-P Energy Currency Molecules Leading Up to the Formation of Organophosphorus Compounds.
- Author
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Gull, Maheen, Feng, Tian, Cruz, Harold A., Krishnamurthy, Ramanarayanan, and Pasek, Matthew A.
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ORGANOPHOSPHORUS compounds , *MINERAL dusts , *PHOSPHORUS compounds , *DUST , *INTERPLANETARY dust , *OXIDATION states - Abstract
The in-fall of meteorites and interstellar dust particles during the Hadean–Archean heavy bombardment may have provided the early Earth with various reduced oxidation state phosphorus compounds and minerals, including phosphite (HPO32−)([Pi(III)]). The ion phosphite ([Pi(III)])has been postulated to be ubiquitous on the early Earth and consequently could have played a role in the emergence of organophosphorus compounds and other prebiotically relevant P species such as condensed P compounds, e.g., pyrophosphite ([PPi(III)]) and isohypophosphate ([PPi(III–V)]). In the present study, we show that phosphite ([Pi(III)]) oxidizes under mild heating conditions (e.g., wet–dry cycles and a prebiotic scenario mimicking a mildly hot-evaporating/drying pool on the early Earth at 78–83 °C) in the presence of urea and other additives, resulting in changes to orthophosphate ([Pi(V)]) alongside the formation of reactive condensed P compounds (e.g., pyrophosphite ([PPi(III)]) and isohypophosphate ([PPi(III–V)])) through a one-pot mechanism. Additionally, we also show that phosphite ([Pi(III)]) and the condensed P compounds readily react with organics (nucleosides and organic alcohol) to form organophosphorus compounds. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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15. COMPLETE MONOTONICITY INVOLVING THE DIVIDED DIFFERENCE OF POLYGAMMA FUNCTIONS.
- Author
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Zhen-Hang Yang and Jing-Feng Tian
- Abstract
For r, s ∈ R and ρ = min {r, s}, let D [x + r, x + s; ψn-1] ≡ -φn (x) be the divided difference of the functions ψn-1 = (-1)n ψ(n-1) (n ∈ N) on (-ρ, ∞), where ψ(n) stands for the polygamma functions. In this paper, we present the necessary and sufficient conditions for the functions... to be completely monotonic on (-ρ, ∞), where mi, ni ∈ N for i = 1, ..., k with k ≥ 2 and .... These generalize known results and gives an answer to a problem. [ABSTRACT FROM AUTHOR]
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- 2023
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16. Shaping the Probability Density Function of the Output Response in a Reverberation Chamber.
- Author
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Qian Xu, Feng Tian, Yongjiu Zhao, Rui Jia, Erwei Cheng, and Lei Xing
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REVERBERATION chambers , *SEPARATION of variables , *PROBABILITY density function - Abstract
This paper shows that the received power and E-field in a reverberation chamber (RC) can be shaped by tuning the statistical properties of input signals. For a given probability density function (PDF) of an RC response, the Fourier transform method can be applied to find the PDF of the input signal. Numerical and measurement verifications are given to validate the theory. Limitations are also analyzed and discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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17. Analysis of Effect of Ground Experiment Environment on Plasma Contactor Performance.
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Feng Tian, Long Miao, Qimeng Xia, Ningfei Wang, and Xiao Hou
- Abstract
The large difference in the working performance of a hollow cathode plasma contactor between the ground and actual on-orbit environments will cause difficulties in selecting a ground-test schemes to fully simulate the contactor real on-orbit characteristics. In this study, the effect of the simulated anode size and structure, the simulated anode surface state, the flow rate of background working gas, and the background plasma density on the emission characteristics and plume structure of the contactor are studied. Three self-made simulated anodes of different sizes and structures are applied in the ground experiments. The change of anode surface state (particularly the ability of absorbing electrons) is realized by dividing the self-made simulated anodes into four double-separated regions and alternatively electrically isolating them. An additional gas channel and an auxiliary contactor are used to create background working gas and a low-Earth-orbit plasma atmosphere, respectively. The voltage-current curves as well as the plasma parameter distributions at the contactor exit and in the far-field regions are determined under different regimes and working conditions. The relationship between the contactor's emission characteristics and plume structure is clarified. The experimental results could provide useful information for instructing the contactor design and developing a real on-orbit experiment plan. [ABSTRACT FROM AUTHOR]
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- 2023
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18. Organophosphorus Compound Formation Through the Oxidation of Reduced Oxidation State Phosphorus Compounds on the Hadean Earth.
- Author
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Gull, Maheen, Feng, Tian, Bracegirdle, Joe, Abbott-Lyon, Heather, and Pasek, Matthew A.
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OXIDATION states , *PHOSPHORUS compounds , *HADEAN , *PHOSPHATE minerals , *INORGANIC compounds , *ORGANOPHOSPHORUS compounds , *ADENOSINES , *OXIDATION , *HABER-Weiss reaction - Abstract
Reduced oxidation state phosphorus compounds may have been brought to the early Earth via meteorites or could have formed through geologic processes. These compounds could have played a role in the origin of biological phosphorus (P, hereafter) compounds. Reduced oxidation state P compounds are generally more soluble in water and are more reactive than orthophosphate and its associated minerals. However, to date no facile routes to generate C–O–P type compounds using reduced oxidation state P compounds have been reported under prebiotic conditions. In this study, we investigate the reactions between reduced oxidation state P compounds—and their oxidized products generated via Fenton reactions—with the nucleosides uridine and adenosine. The inorganic P compounds generated via Fenton chemistry readily react with nucleosides to produce organophosphites and organophosphates, including phosphate diesters via one-pot syntheses. The reactions were facilitated by NH4+ ions and urea as a condensation agent. We also present the results of the plausible stability of the organic compounds such as adenosine in an environment containing an abundance of H2O2. Such results have direct implications on finding organic compounds in Martian environments and other rocky planets (including early Earth) that were richer in H2O2 than O2. Finally, we also suggest a route for the sink of these inorganic P compounds, as a part of a plausible natural P cycle and show the possible formation of secondary phosphate minerals such as struvite and brushite on the early Earth. [ABSTRACT FROM AUTHOR]
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- 2023
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19. Monotonicity and complete monotonicity of some functions involving the modified Bessel functions of the second kind.
- Author
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Zhong-Xuan Mao and Jing-Feng Tian
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BESSEL functions , *INTEGRALS - Abstract
In this paper, we introduce some monotonicity rules for the ratio of integrals. Furthermore, we demonstrate that the function -- Tν, α β(s) is completely monotonic in s and absolutely monotonic in ν if and only if β 1, where Tν, α β(s) = Kν²(s) -- βKν-α(s)Kν+α(s) defined on s > 0 and Kν(s) is the modified Bessel function of the second kind of order ν. Finally, we determine the necessary and sufficient conditions for the functions s → Tµ,α1(s)/Tν, α,1(s), s → (Tν, α,1(s))/(2T(µ+ν)/2,α,1(s)), and ... Tν, α,1(s)/... ν, α,1 (s) to be monotonic in s ∈ (0, ∞) by employing the monotonicity rules. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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20. Immunity of two novel hepatitis C virus polyepitope vaccines.
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Feng, Tian, Li, Mingzhi, Zhang, Lirong, Li, Sha, Yang, Zibing, Kang, Lumei, Guo, Yunli, Kong, Lingbao, and Wang, Ting
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HEPATITIS C vaccines , *ESCHERICHIA coli , *IMMUNITY , *HUMORAL immunity , *RECOMBINANT proteins - Abstract
• Two novel HCV multiepitope vaccines R9-Bp and LTB-R9-Bp are expressed in E.coli. • Both R9-Bp and LTB-R9-Bp elicit antibodies and cytokines in mice. • The antibodies induced by both R9-Bp and LTB-R9-Bp inhibit significantly HCV entry. Hepatitis C virus (HCV) infection remains a serious public health burden around the world. So far there is no effective vaccine against this virus. Neutralizing antibody (NAb) responses to the epitopes within HCV E1 and E2 proteins are related to the resolution of hepatitis C infection. E. coli heat-labile enterotoxin B subunit (LTB) has been described as potent immunity adjuvants. In this study, we constructed recombinant pET vectors: pET-R9-Bp (B cell polyepitopes) expressing 7 epitopes from HCV E1 and E2 proteins including R9 (E2 384-411aa)-Bp (E1 313-327aa -E2 396-424aa -E2 436-447aa -E2 523-540aa -E2 610-627aa -E2 631-648aa) and pET-LTB-R9-Bp expressing LTB adjuvant in combination with R9-Bp. Recombinant proteins R9-Bp and LTB-R9-Bp were expressed successfully in E. coli and purified by the Ni-NTA column. Both R9-Bp and LTB-R9-Bp in BALB/c mice induced robust humoral immune response in the context of intraperitoneal or intramuscular immunization but not oral immunization. Intraperitoneal administration of LTB-R9-Bp induced a higher antibody titer (peak titer: 1:341000) than that of R9-Bp (peak titer: 1:85000) after the second boost (P = 0.0036 or 0.0002). However, comparable antibody peak titers were elicited for both R9-Bp and LTB-R9-Bp in intramuscular immunization albeit with significant difference (P = 0.0032) a week after the second boost. In addition, both R9-Bp and LTB-R9-Bp induced the secretion of cytokines including IFN-γ and IL-4 at similar levels. anti-sera induced by both R9-Bp and LTB-R9-Bp recognized native HCV E1 and E2 proteins. Moreover, these HCV-specific antisera inhibited significantly the entry of HCV (P < 0.0001). Taken together, these findings showed that E. coli -based both R9-Bp and LTB-R9-Bp could become promising HCV vaccines. [ABSTRACT FROM AUTHOR]
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- 2022
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21. Electrochemical C–H Functionalization of Cyclic Amines.
- Author
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Feng, Tian, Wang, Siyi, and Qiu, Youai
- Abstract
Functionalized cyclic amines are essential structural motifs in synthetic chemistry and pharmaceutical chemistry, and Shono-type oxidation is a well-developed electrochemical approach for the synthesis of α- amines. In sharp contrast, electrochemically driven direct β-C(sp3)–H functionalization of amines has been far proven elusive. Herein, we outline the recent advances in this field and highlight our group's effort to achieve electrochemical β-C(sp3)–H functionalization assisted by ferrocene as molecular electrocatalyst under mild conditions. 1 Introduction 2 Case studies of α-Functionalization (Shono-Type Oxidation) 3 Electrochemical β-C(sp3)–H Acylation 4 Conclusion [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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22. Results of an Eight-Year Extraction of Phosphorus Minerals within the Seymchan Meteorite.
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Gull, Maheen, Feng, Tian, and Pasek, Matthew A.
- Subjects
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PHOSPHIDES , *METEORITES , *IRON meteorites , *MINERALS , *DUST , *OBSIDIAN , *FORMAMIDE - Abstract
Simple Summary: Phosphorus (P) is essential to life in the form of various phosphate esters that make up DNA, RNA and other cellular structures. It mainly exists in the form of phosphate. However, other reduced-oxidation-state P compounds have also been found in natural waters, in living organisms, and in natural glasses formed by lightning called fulgurites. Iron meteorites often bear a P mineral, schreibersite, which corrodes in water to produce various P species including reduced-oxidation-state compounds such as phosphite. This form of natural P is reactive and unstable as ultimately the phosphides and phosphites convert into phosphate, the most stable form of P on an oxidizing world. Previous analyses of 3.5 billion rocks identified various P species including phosphite revealing that phosphite was present on the early Earth and, despite its reactivity, it was stable under geologic timescales. In the present communication, we present the analyses of a meteoritic sample, the pallasite Seymchan, which is rich in the mineral schreibersite and was allowed to corrode for eight years in water. At room temperature, the schreibersite corroded in water to give P species including phosphate and phosphite. These results indicate that phosphite is not an ephemeral species and it is stable enough to be detected in multiple environments. In-fall of extraterrestrial material including meteorites and interstellar dust particles during the late heavy bombardment are known to have brought substantial amounts of reduced oxidation-state phosphorus to the early Earth in the form of siderophilic minerals, e.g., schreibersite ((FeNi)3P). In this report, we present results on the reaction of meteoritic phosphide minerals in the Seymchan meteorite in ultrapure water for 8 years. The ions produced during schreibersite corrosion (phosphite, hypophosphate, pyrophosphate, and phosphate) are stable and persistent in aqueous solution over this timescale. These results were also compared with the short-term corrosion reactions of the meteoritic mineral schreibersite's synthetic analog Fe3P in aqueous and non-aqueous solutions (ultrapure water and formamide). This finding suggests that the reduced-oxidation-state phosphorus (P) compounds including phosphite could be ubiquitous and stable on the early Earth over a long span of time and such compounds could be readily available on the early Earth. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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23. Planar Pattern Manipulation Surfaces Using Dual-Polarized Pin-Loaded Patch Resonating Elements.
- Author
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Feng, Tian-Xi, Zhu, Lei, Wei, Tao, and Li, Bo
- Subjects
- *
SHORT selling (Securities) , *REFLECTANCE - Abstract
This article proposes a novel design concept to realize planar pattern manipulation surfaces (PPMSs) using dual-polarized pin-loaded patch resonating elements. First, the resonant frequency and reflection coefficient of the pin-loaded patch element are investigated through its equivalent circuit model. By changing the positions of shorting pins, the reflection phase of such a patch element can be appropriately adjusted while maintaining the reflection magnitude unchanged. Additionally, varying the positions of shorting pins possesses a significant property of polarization independence. Then, the dual-polarized pin-loaded patch element is employed to design the proposed PPMS. In this way, the incident wave is manipulated for different reflection angles with the dual-polarization response by adjusting the position distributions of shorting pins in two orthogonal polarization directions. To prove our presented design concept, two prototypes with reflection angles of ($\theta ^{r} = 45^{\circ }$ , $\phi ^{r} = 0^{\circ }$) and ($\theta ^{r} = 45^{\circ }$ , $\phi ^{r} = 45^{\circ }$) are finally implemented, fabricated, and measured. Measurements and calculations agree well with each other, which indicates that the reflection angle is experimentally obtained as predicted in theory. Thus, the proposed PPMS can be apparently viewed as a promising candidate to efficiently customize the radio environment in future wireless networks. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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- View/download PDF
24. 3-D Pattern Modulation Surfaces Using Short-Circuited Slotline Structure: Proposal, Design, and Implementation.
- Author
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Feng, Tian-Xi, Zhu, Lei, Zhao, Xuankai, and Li, Bo
- Subjects
- *
REFLECTANCE , *SOFTWARE radio , *ELECTRONIC modulation , *PLANE wavefronts , *ELECTRIC lines - Abstract
This article presents the proposal, design, and implementation of 3-D pattern modulation surfaces (PMSs) using short-circuited slotline structure. First, the reflection coefficient of short-circuited slotline with a certain length is studied using the equivalent transmission line model. Since the magnitude of its reflection coefficient nearly equals 1, the TE-polarized incident plane wave can be almost fully reflected at the input terminal of each short-circuited slotline. Most importantly, the phase of its reflection coefficient can be freely changed and adjusted by only varying the length of short-circuited slotline. Then, the short-circuited slotline structure is used as the key element of the proposed PMS. In this way, the functionality of pattern modulation is obtained by unequally selecting the lengths of a row of short-circuited slotlines. Finally, three prototypes with modulated angles of 15°, 30°, and 45° are fabricated and tested to validate our design concept. The measured results agree well with the calculations, showing that the predicted reflection angles are realized using short-circuited slotlines. Therefore, the proposed 3-D PMS is evidently verified to be a promising candidate for future wireless networks to achieve pattern modulation in a smart radio environment. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
25. Designs of planar pattern manipulation surfaces using patch resonating elements loading with dual‐polarized slots for multi‐user systems.
- Author
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Feng, Tian‐Xi, Zhu, Lei, Zhang, Wanping, and Li, Bo
- Subjects
- *
REFLECTANCE , *TELECOMMUNICATION systems , *COPLANAR waveguides , *SUBSTRATE integrated waveguides - Abstract
In this article, we propose the designs of planar pattern manipulation surfaces (PPMSs) applying patch resonating elements loading with dual‐polarized slots for multi‐user communication systems in future networks. Firstly, the amplitude and phase of the element reflection coefficient are discussed with resorting to the varied length of the slot. Secondly, the dual‐polarized slot‐loaded patch is consequently utilized for obtaining the proposed PPMS. By suitably selecting the reflection coefficient distribution of the entire PPMS, the reflected wave can be manipulated to gain different dual‐beam reflection properties with the response of dual‐polarization. In the final, two prototypes with 10 × 10 elements are fabricated and tested to prove the presented design concept. Measurements agree well with calculated results, indicating that dual‐beam reflections with the controllable beam pointing ability are well achieved so as to provide effective coverage for multiple users simultaneously. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
26. Recent Advances in Electrocarboxylation with CO2.
- Author
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Wang, Siyi, Feng, Tian, Wang, Yanwei, and Qiu, Youai
- Subjects
- *
CARBOXYLATION , *ORGANIC synthesis , *CARBON dioxide , *RENEWABLE natural resources - Abstract
Carbon dioxide (CO2) is an abundant, inexpensive, renewable C1 resource and the main component of greenhouse gas, thereby the research for its sustainable and efficient conversion has received notable attention in recent years. Electrochemical organic synthesis, as a green and efficient synthetic method, is convinced to be an ideal approach for CO2 utilization. In this review, recent advances in electrocarboxylation with CO2 were summarized through different reaction types, which would disclose the great potential of electrocarboxylation in green organic synthesis. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
27. Integrating the effects of driving forces on ecosystem services into ecological management: A case study from Sichuan Province, China.
- Author
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Huang, Ying, Feng, Tian, Niu, Shaofei, Hao, Desheng, Gan, Xiaoyu, and Zhou, Bo
- Subjects
- *
ECOSYSTEM services , *WATER conservation , *SOIL conservation , *ECOLOGICAL models , *SOIL moisture , *SUSTAINABLE development - Abstract
Driving forces are the factors that lead to the observed changes in the quantity and quality of ecosystem services (ESs). The relationship between driving forces and ESs involves considerable scale-related information. Place-based ecological management requires this information to support local sustainable development. Despite the importance of scale in ES research, most studies have only examined the association between ESs and their drivers at a single level, and few studies have examined this relationship at various scales or analyzed spatial heterogeneity. The purpose of this paper is to explore the significance of the scale-dependent effects of drivers on ESs for localized ecological management. The biophysical values of ESs were calculated using several ecological simulation models. The effects of driving forces on ESs were explored using the geographically weighted regression (GWR) model. Variations in the effects of driving forces on ESs were examined at three scales: provincial, ecoregional, and subecoregional scales. Finally, canonical correlation analysis was used to identify the major environmental factors associated with these variations in each ecoregion. Our results show that (1) the distribution of soil conservation and water yield is highly heterogeneous; (2) four driving forces have significant positive and negative impacts on soil conservation and water yield, and their effects on the two services vary spatially (p < 0.05); (3) the impacts of drivers on ESs vary across different spatial scales, with a corresponding shift in the related environmental factors; and (4) in the study area, at the provincial scale, physical, topographical, and biophysical factors were key factors associated with the variations in the relationship between ESs and drivers, and at the ecoregional and subecoregional scales, physical, socioeconomic, topographical, and biophysical factors all contributed to these changes. Our results suggest that significant differences in topographical conditions (e.g., altitude, slope) can be incorporated for exploring the relationship between drivers and ESs and optimizing ecological management at the provincial scale, whereas significant differences in physical and socioeconomic conditions (e.g., urbanization levels, human activity, vegetation coverage) are more meaningful for localized ecological management at the ecoregional and subecological scales. These findings provide a basis for understanding the relationship between drivers and ESs at multiple scales as well as guidelines for improving localized ecological management and achieving sustainable development. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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28. Clinical and Pathological Benefits of Scallop-Derived Plasmalogen in a Novel Mouse Model of Alzheimer's Disease with Chronic Cerebral Hypoperfusion.
- Author
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Feng, Tian, Hu, Xinran, Fukui, Yusuke, Bian, Zhihong, Bian, Yuting, Sun, Hongming, Takemoto, Mami, Yunoki, Taijun, Nakano, Yumiko, Morihara, Ryuta, Abe, Koji, and Yamashita, Toru
- Subjects
- *
ALZHEIMER'S disease , *LABORATORY mice , *CHRONIC diseases , *ANIMAL disease models , *CEREBRAL circulation , *BIOLOGICAL models , *BRAIN , *INVERTEBRATES , *DEMENTIA , *CEREBRAL ischemia , *MICE , *ANIMALS - Abstract
Background: The oral ingestion of scallop-derived plasmalogen (sPlas) significantly improved cognitive function in Alzheimer's disease (AD) patients.Objective: However, the effects and mechanisms of sPlas on AD with chronic cerebral hypoperfusion (CCH), a class of mixed dementia contributing to 20-30% among the dementia society, were still elusive.Methods: In the present study, we applied a novel mouse model of AD with CCH to investigate the potential effects of sPlas on AD with CCH.Results: The present study demonstrated that sPlas significantly recovered cerebral blood flow, improved motor and cognitive deficits, reduced amyloid-β pathology, regulated neuroinflammation, ameliorated neural oxidative stress, and inhibited neuronal loss in AD with CCH mice at 12 M.Conclusion: These findings suggest that sPlas possesses clinical and pathological benefits for AD with CCH in the novel model mice. Furthermore, sPlas could have promising prevention and therapeutic effects on patients of AD with CCH. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
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29. When energy meets blockchain: A systematic exposition of policies, research hotspots, applications, and prospects.
- Author
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Zha, Dao‐Shun, Feng, Tian‐Tian, Gong, Xiao‐Lei, and Liu, Shu‐Yue
- Subjects
- *
ENERGY development , *BLOCKCHAINS , *POWER resources , *EXHIBITIONS , *INSTITUTIONAL cooperation - Abstract
Summary: Nowadays, energy development has been plagued by such problems as the difficulty of controlling energy development and ensuring the balance of supply and demand, the serious overcapacity, and the redundancy of energy resource circulation. Blockchain technology is highly compatible with such field because of its features including decentralization, openness, independence, security, anonymity, etc. The current studies on "blockchain+energy" are focused on the application and remain insufficient on the current situation of cooperation between various subjects, with most research featuring qualitative analysis. This article employs Vosviewer for bibliometric analysis and then, from both qualitative and quantitative perspectives, provides a systematic literature review in the field of "blockchain+energy" via scientific cartography. Meanwhile, this review is diversified for also analyzing ample aspects, such as policies and regulations, national cooperation, institutional cooperation, author cooperation, research hotspots, research differences, application progress, development trend, etc. Based on the research results, policy recommendations are proposed in terms of external environment and internal technology, including one that the external environment should focus on policy support and talent cultivation, and the internal technology should focus on blockchain core technology development and security control. In this way, this article aims to provide reference for the future blockchain research, application model innovation, and relevant policy makers. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
30. Electrochemical Desaturative β‐Acylation of Cyclic N‐Aryl Amines.
- Author
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Feng, Tian, Wang, Siyi, Liu, Yin, Liu, Shouzhuo, and Qiu, Youai
- Subjects
- *
AMINES , *OXIDATION-reduction reaction , *CYCLIC voltammetry , *ACYLATION , *FERROCENE - Abstract
Herein, we disclose a straightforward, robust, and simple route to access β‐substituted desaturated cyclic amines via an electrochemically driven desaturative β‐functionalization of cyclic amines. This transformation is based on multiple single‐electron oxidation processes using catalytic amounts of ferrocene. The reaction proceeds in the absence of stoichiometric amounts of electrolyte under mild conditions, affording the desired products with high chemo‐ and regioselectivity. The reaction was tolerant of a broad range of substrates and also enables late‐stage β‐C(sp3)−H acylation of potentially valuable products. Preliminary mechanistic studies using cyclic voltammetry reveal the key role of ferrocene as a redox mediator in the reaction. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
31. Electrochemical Desaturative β‐Acylation of Cyclic N‐Aryl Amines.
- Author
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Feng, Tian, Wang, Siyi, Liu, Yin, Liu, Shouzhuo, and Qiu, Youai
- Subjects
- *
AMINES , *CYCLIC voltammetry , *OXIDATION-reduction reaction , *ACYLATION , *FERROCENE - Abstract
Herein, we disclose a straightforward, robust, and simple route to access β‐substituted desaturated cyclic amines via an electrochemically driven desaturative β‐functionalization of cyclic amines. This transformation is based on multiple single‐electron oxidation processes using catalytic amounts of ferrocene. The reaction proceeds in the absence of stoichiometric amounts of electrolyte under mild conditions, affording the desired products with high chemo‐ and regioselectivity. The reaction was tolerant of a broad range of substrates and also enables late‐stage β‐C(sp3)−H acylation of potentially valuable products. Preliminary mechanistic studies using cyclic voltammetry reveal the key role of ferrocene as a redox mediator in the reaction. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
32. Event-triggered robust tracking control for fractional-order uncertain systems.
- Author
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Feng, Tian, Wu, Baowei, and Chen, YangQuan
- Subjects
- *
UNCERTAIN systems , *ROBUST control , *COMPUTER simulation - Abstract
In this paper, based on event-triggered (ET) mechanisms, the problem of output tracking for a class of fractional-order uncertain systems with order 0 < α < 1 is investigated. Owing to the difficulties of measuring system full-state in practice, output tracking error is firstly used to construct an ET condition, which eventually decides whether the current signal should be transmitted. Then, by utilizing the designed error-based feedback controller, some sufficient conditions are presented to ensure that the controlled system output asymptotically tracks the reference signal. Finally, numerical simulations are performed to validate the effectiveness of the theoretical formulation. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
33. Blockchain-based smart trading mechanism for renewable energy power consumption vouchers and green certificates: Platform design and simulation.
- Author
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Guo, Shi-man and Feng, Tian-tian
- Subjects
- *
SUSTAINABLE consumption , *ENERGY consumption , *BLOCKCHAINS , *RENEWABLE energy sources , *GREEN technology , *DATABASES , *BALANCE of trade - Abstract
As the renewable energy consumption responsibility weight system is gradually implemented in various provinces, there is a closer intersection between the excess consumption and green certificates trading. Existing trading platforms can only meet the needs of green certificates trading. This single-platform solution is no longer sufficient to meet the trading requirements under this system. Consequently, this paper proposes a excess consumption and green certificates trading platform based on blockchain technology. This platform utilizes the decentralized, open, and anonymous characteristics of blockchain technology and rely on its smart contract capabilities to simultaneously meet the comprehensive trading needs of surplus consumption and green certificates trading through combining user-initiated transactions with platform-intelligent recommendations. It adapts to the complex excess consumption and green certificates trading market that has emerged following the issuance of the renewable energy consumption responsibility weighting policy. To conduct simulated transactions, 16 groups of buyers simulate a total of 215,792 excess consumption vouchers and 143,861 green certificates in this paper. The transaction results all meet the expected transaction scenarios under the conditions of smart recommendation, demonstrating the platform's transaction feasibility. [Display omitted] • Design a blockchain-based smart contract solution for volume consumption trading and green certificate trading. • Build a database containing 215,792 excess consumption vouchers and 143,861 green power certificates. • Simulate the purchase of 160 buyers by establish a transaction platform. • Analyzed the application direction of the data produced by the trading platform [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Microseismic constraints on the mechanical state of the Anninghe-Daliangshan fault zone, southeastern Tibetan Plateau.
- Author
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Feng, Tian, Wang, Ruijia, Fang, Lihua, Wu, Jianping, and Yang, Ting
- Subjects
- *
EARTHQUAKE hazard analysis , *FAULT zones , *EARTHQUAKES , *SEISMIC arrays , *MACHINE learning - Abstract
• We built a high-resolution earthquake catalog for the Anninghe-Daliangshan fault zone. • The ∼16,000 events exhibit variable spatiotemporal patterns and statistical properties. • The northern Daliangshan fault hosts both seismic and aseismic slip with deep microseismicity. • The southern Anninghe fault is locked and preparing for two ∼M7.3 earthquakes. The mechanical state (i.e., creeping or locked) of fault zone systems implies future seismic hazards. The Anninghe-Daliangshan fault zone in southeastern Tibet serves as the central curved segment of the most seismically active fault system in mainland China, which has produced a remarkable sequence of historical large earthquakes. To better understand its deformation modes and seismic-aseismic slip partitioning, we built a high-resolution earthquake catalog along the Anninghe fault (ANHF) zone and the Daliangshan fault (DLSF) zone utilizing a dense seismic array deployed between 2017 and 2022. The machine-learning based workflow produces ∼16,000 events with various behaviors and patterns located within the two fault zones. We then systematically evaluated and compared the spatiotemporal seismic patterns, seismic slip rate, statistical properties (b -value, C V value, and nearest neighbor distance distribution), as well as geodetic measurements. Our results infer that the lower seismogenic crust (16–30 km; brittle) of the northern DLSF zone is creeping and releasing elastic strain with abundant microearthquakes; and the northern ANHF behaves similarly. Moving toward the south, the ANHF transits to a locked state, characterized by sparse seismicity, significantly low seismic energy release and a low b -value. Separated around Mianning, the locked segment is prone to generate two ∼M7.3 earthquakes, posing significant seismic hazard to approximately one million residents nearby. Overall, our updated analysis on the creeping northern DLSF and locked southern ANHF could deepen the understanding of seismic behavior along in-land fault system and guide future seismic hazard assessment in densely populated Southwest China. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. ZnS:Mn Quantum Dots Coated with a Silica Molecularly Imprinted Polymer for Trace Teflubenzuron Detection in Vegetable Samples.
- Author
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Feng, Tian, Chen, Zhenkun, and Cheng, Xiaomin
- Abstract
A novel nanocomposite fluorescent probe consisting of quantum dots and a silica molecularly imprinted polymer (MIPs-capped ZnS:Mn QDs) was synthesized and applied for the rapid detection of teflubenzuron (TBZ) based on the fluorescence quenching of a composite probe via TBZ. The fluorescence quenching efficiency of MIP@SiO2@ZnS:Mn QDs displayed a linear relationship over the concentration range of 0–26.24 μmol/L with a correlation coefficient of 0.9857 and the limit of detection was 2.4 μg/L. The selectivity test showed that the nanocomposite had good selectively rebind TBZ with higher imprinting factor of 3.06 compared with four structurally similar compounds. In addition, the probe was successfully applied to the detection of TBZ in vegetable samples with a recovery of 90.3~97.1% and with a relative standard deviation below 3.2%. This developed method has the advantages of simple preparation, fast response and low toxicity for trace TBZ detection. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. A NEW CHAIN OF INEQUALITIES INVOLVING THE TOADER-QI, LOGARITHMIC AND EXPONENTIAL MEANS.
- Author
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Zhen-Hang Yang and Jing-Feng Tian
- Subjects
- *
ARITHMETIC mean , *BESSEL functions , *HYPERBOLIC functions - Abstract
In this paper, we establish an interesting chain of sharp inequalities involving Toader-Qi mean, exponential mean, logarithmic mean, arithmetic mean and geometric mean. This greatly improves some existing results. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
37. High SPINK4 Expression Predicts Poor Outcomes among Rectal Cancer Patients Receiving CCRT.
- Author
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Tzu-Ju Chen, Yu-Feng Tian, Chia-Lin Chou, Ti-Chun Chan, Hong-Lin He, Wan-Shan Li, Hsin-Hwa Tsai, Chien-Feng Li, and Hong-Yue Lai
- Subjects
- *
RECTAL cancer , *CANCER patients , *PROGNOSIS , *RECTAL surgery , *LYMPHATIC metastasis , *TREATMENT effectiveness , *TRANSCRIPTOMES - Abstract
Background: Patients with rectal cancer can prospectively be favored for neoadjuvant concurrent chemoradiotherapy (CCRT) to downstage before a radical proctectomy, but the risk stratification and clinical outcomes remain disappointing. Methods: From a published rectal cancer transcriptome dataset (GSE35452), we highlighted extracellular matrix (ECM)-linked genes and identified the serine protease inhibitor Kazal-type 4 (SPINK4) gene as the most relevant among the top 10 differentially expressed genes associated with CCRT resistance. We accumulated the cases of 172 rectal cancer patients who received neoadjuvant CCRT followed by surgery and collected tumor specimens for the evaluation of the expression of SPINK4 using immunohistochemistry. Results: The results revealed that high SPINK4 immunoexpression was significantly related to advanced pre-CCRT and post-CCRT tumor status (both p < 0.001), post-CCRT lymph node metastasis (p = 0.001), more vascular and perineurial invasion (p = 0.015 and p = 0.023), and a lower degree of tumor regression (p = 0.001). In univariate analyses, high SPINK4 immunoexpression was remarkably correlated with worse disease-specific survival (DSS) (p < 0.0001), local recurrence-free survival (LRFS) (p = 0.0017), and metastasis-free survival (MeFS) (p < 0.0001). Furthermore, in multivariate analyses, high SPINK4 immunoexpression remained independently prognostic of inferior DSS and MeFS (p = 0.004 and p = 0.002). Conclusion: These results imply that high SPINK4 expression is associated with advanced clinicopathological features and a poor therapeutic response among rectal cancer patients undergoing CCRT, thus validating the prospective prognostic value of SPINK4 for those patients. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
38. Protective effects of edaravone on white matter pathology in a novel mouse model of Alzheimer's disease with chronic cerebral hypoperfusion.
- Author
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Feng, Tian, Yamashita, Toru, Sasaki, Ryo, Tadokoro, Koh, Matsumoto, Namiko, Hishikawa, Nozomi, and Abe, Koji
- Abstract
White matter lesions (WMLs) caused by cerebral chronic hypoperfusion (CCH) may contribute to the pathophysiology of Alzheimer's disease (AD). However, the underlying mechanisms and therapeutic approaches have yet to be totally identified. In the present study, we investigated a potential therapeutic effect of the free radical scavenger edaravone (EDA) on WMLs in our previously reported novel mouse model of AD (APP23) plus CCH with motor and cognitive deficits. Relative to AD with CCH mice at 12 months (M) of age, EDA strongly improved CCH-induced WMLs in the corpus callosum of APP23 mice at 12 M by improving the disruption of white matter integrity, enhancing the proliferation of oligodendrocyte progenitor cells, attenuating endothelium/astrocyte unit dysfunction, and reducing neuroinflammation and oxidative stress. The present study demonstrates that the long-term administration of EDA may provide a promising therapeutic approach for WMLs in AD plus CCH disease with cognitive deficits. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
39. Air Pollution Zone Migrates South Driven by East Asian Winter Monsoon and Climate Change.
- Author
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Zhao, Shuyu, Feng, Tian, Tie, Xuexi, Li, Guohui, and Cao, Junji
- Subjects
- *
CLIMATE change , *AIR pollution control , *MONSOONS , *CARBON offsetting , *WINTER - Abstract
A variety of climatological indices have been established to illustrate the impact of climate change on air pollution in China, but major facts for causing variations of air pollution attributed to climate change are still unclear. Here, using in‐situ PM2.5 (particles with the aerodynamic diameter less than 2.5 μm) measurement, atmospheric reanalysis data and a chemical transport model, we show that meridional distribution of PM2.5 loadings is strongly modulated by the intensity of East Asian winter monsoon (EAWM). The EAWM drives the heavily polluted zone in eastern China to migrate southward, i.e., under stronger EAWM, more southward migration of air pollution occurs. We expect that the migration will likely re‐distribute carbon sources‐ and sinks‐related ecosystem, posing a new challenge for the Chinese government, who needs to implement region‐different emission reduction plans in the future, to mitigate air pollution and to go carbon neutral. Plain Language Summary: The relationship between the severe air pollution in China and climate has drawn much attention from scientific community, which still remains unclear. In this study, we present that air pollution with high PM2.5 loadings in winter, China is significantly modulated by East Asian winter monsoon (EAWM) based on ambient PM2.5 measurements, atmospheric reanalysis data and the GEOS‐Chem model. We find that the change in EAWM intensity dominates the location of heavily polluted zone and its meridional distribution. Stronger EAWM generally drives the zone to migrate more southward in eastern China, highlighting the predominant role of EAWM in redistributing air pollution of China during wintertime. Under climate change, the inter‐annual variability and decadal oscillation of EAWM projected by CMIP5 and CMIP6 models indicate a southward migration of the heavily polluted zone in next decades, probably approaching the Yangtze River Delta. This result may pose new challenges in air pollution control for local governments in different regions regarding climatic influence. Key Points: East Asian winter monsoon strongly modulates PM2.5 levels meridionally in eastern ChinaUnder climate change, the heavily polluted zone will likely move southward to Yangtze River Delta in the next decadesChina needs to implement regional‐different emission reduction measures regarding to the influence of climate change [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
40. Construction of Alkali-metal-based Imidazolecarboxylate Coordination Polymers as Efficient Catalysts for Solventfree Ring-opening polymerization of ɛ-Caprolactone.
- Author
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Feng Tian, Nan Shen, Kun-Lin Huang, Sheng-Chun Chen, Qun Chen, and Ming-Yang He
- Subjects
- *
ALKALI metals , *RING-opening polymerization , *COORDINATION polymers , *DICARBOXYLIC acids , *X-ray powder diffraction , *CATALYSTS , *RADIUS (Geometry) , *SINGLE crystals - Abstract
A series of new alkali-metal-based coordination polymers, [Li(H2IMDC)(H2O)]n (1), [Na2(H2IMDC)2(H3IMDC)2(H2O)4]n (2), and [K(H2IMDC)(H2O)]n (3), have been constructed under solvothermal conditions by using imidazole-4,5-dicarboxylic acid (H3IMDC) as ligand. The structure of the complexes has been determined by single-crystal X-ray diffraction and further characterized by elemental analyses, IR spectra, powder X-ray diffraction and thermogravimetric analyses. The single crystal Xray structural studies showed that their structural dimensionalities varying from 1-D zigzag chain, 2-D 44-sql network to 3-D 4,6-connected coordination framework are strongly governed by the ionic radii and coordination geometries of the metal cations. For the first time, the alkali-metal-based coordination polymers were demonstrated to be effective catalysts for the solvent-free ring-opening polymerization (ROP) of ɛ-caprolactone. The catalytic activity of complexes 1–3 depends on the metal cations, increasing in the order Li+ < Na+ < K+. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
41. A high-quality de novo genome assembly of one swamp eel (Monopterus albus) strain with PacBio and Hi-C sequencing data.
- Author
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Hai-Feng Tian, Qiao-Mu Hu, and Zhong Li
- Subjects
- *
SWAMPS , *EELS , *GENOMES , *OSTEICHTHYES , *CHROMOSOMES , *GENE families , *MYOGLOBIN - Abstract
The swamp eel (Monopterus albus) is one economically important fish in China and South-Eastern Asia and a good model species to study sex inversion. There are different genetic lineages and multiple local strains of swamp eel in China, and one local strain of M. albus with deep yellow and big spots has been selected for consecutive selective breeding due to superiority in growth rate and fecundity. A high-quality reference genome of the swamp eel would be a very useful resource for future selective breeding program. In the present study, we applied PacBio single-molecule sequencing technique (SMRT) and the high-throughput chromosome conformation capture (Hi-C) technologies to assemble the M. albus genome. A 799 Mb genome was obtained with the contig N50 length of 2.4 Mb and scaffold N50 length of 67.24 Mb, indicating 110-fold and ∼31.87-fold improvement compared to the earlier released assembly (∼22.24 Kb and 2.11 Mb, respectively). Aided with Hi‐C data, a total of 750 contigs were reliably assembled into 12 chromosomes. Using 22,373 protein-coding genes annotated here, the phylogenetic relationships of the swamp eel with other teleosts showed that swamp eel separated from the common ancestor of Zig-zag eel ∼49.9 million years ago, and 769 gene families were found expanded, which are mainly enriched in the immune system, sensory system, and transport and catabolism. This highly accurate, chromosome-level reference genome of M. albus obtained in this work will be used for the development of genome-scale selective breeding. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
42. Rosmarinic acid improves boar sperm quality, antioxidant capacity and energy metabolism at 17°C via AMPK activation.
- Author
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Feng, Tian‐Yu, Lv, Dong‐Liang, Zhang, Xing, Du, Ye‐Qing, Yuan, Yi‐Tian, Chen, Mei‐Jie, Xi, Hua‐Ming, Li, Yu, Han, Ning, and Hu, Jian‐Hong
- Subjects
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OXIDANT status , *REACTIVE oxygen species , *SPERMATOZOA , *BOARS , *ADENOSINE monophosphate , *SEMEN - Abstract
Boar sperm are susceptible to oxidative damage caused by reactive oxygen species (ROS) during storage. Adenosine monophosphate (AMP)‐activated protein kinase (AMPK) is an important therapeutic target, because it is a cellular metabolism energy sensor and key signalling kinase in spermatozoa. We evaluated the effects of rosmarinic acid (RA), an antioxidant, on boar sperm during liquid storage to determine whether it protects boar sperm via AMPK activation. Boar ejaculates were diluted with Modena extender with different concentrations of RA and stored at 17°C for 9 days. Sperm quality parameters, antioxidant capacity, energy metabolism, AMPK phosphorylation and fertility were analysed. Compared with the control, 40 μmol/L significantly improved sperm motility, plasma membrane integrity and acrosome integrity (p <.05). The effective storage time of boar sperm was up to 9 days. On the third and seventh days, the sperm with RA exhibited increased total antioxidant capacity (T‐AOC), superoxide dismutase (SOD) activity, adenosine triphosphate (ATP) content, mitochondrial membrane potential (ΔΨm) and glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) activity, whereas malondialdehyde (MDA) content was significantly decreased (p <.05). Western blot showed that RA, as well as AICAR (AMPK activator), promoted AMPK phosphorylation, whereas Compound C (AMPK inhibitor) inhibited this effect. The sperm–zona pellucida binding experiment showed that 40 μmol/L RA increased the number of sperm attached to the zona pellucida (p <.05). These findings suggest meaningful methods for improved preservation of boar sperm in vitro and provide new insights into the mechanism by which RA protects sperm cells from oxidative damage via AMPK activation. [ABSTRACT FROM AUTHOR]
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- 2020
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43. Detecting Offshore Seismicity: Combining Backprojection Imaging and Matched‐Filter Detection.
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Feng, Tian, Meng, Lingsen, and Huang, Hui
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EARTHQUAKES , *SEISMIC waves , *GEOPHYSICS , *METEOROLOGY , *TOPOLOGY - Abstract
An important manifestation of the background or coseismic deformation surrounding megathrust earthquakes is the offshore microseismicity, which are difficult to be directly detected by land‐based seismic instruments. Here, we improve the capability of detecting offshore events by combining two popular techniques: backprojection (BP) imaging and matched‐filter (MF) detection. The BP method is effective in retrieving offshore seismicity (Mw > 4.5) buried in the coda wave of large earthquakes. The capability of the MF method depends on the availability of the template pool; therefore, the BP‐inferred events can be used as additional templates to expand the MF detections (BP‐MF). We performed the BP‐MF approach in the period within 600 days after the 2011 Mw 9.0 Tohoku earthquake. We find overall 44.2% more offshore events than those listed in the Japan Meteorological Agency (JMA) catalog. In the near‐trench area, we detect 213% more events. Among the newly detected Mw > 4 events, the BP template contributions are twice more than those matched by the JMA templates. Based on the spatial consistency between aftershock‐depleted zones and large coseismic slip, we identify a possible large coseismic slip zone in the near‐trench region offshore Fukushima. Large b values (≥1.2) are found close to large aftershocks, possibly indicating localized pockets of small differential stresses. At several locations close to the trench, p values (0.93–1.11) are higher than those in the inland area (0.64–0.85). This may be due to the larger coseismic slip and hence larger stress drop of the outer‐rise normal‐faulting events compared to the deeper thrust‐faulting events. Key Points: We improve the capability of detecting offshore events by combining backprojection imaging and matched‐filter detection (BP‐MF)The BP‐MF approach detects twice more events in the near‐trench region than those of the JMA catalogWe identify a possible large‐slip zone in the near‐trench region offshore Fukushima based on aftershock‐depleted zones [ABSTRACT FROM AUTHOR]
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- 2020
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44. Perihilar Hepatectomy for Hepatolithiasis with Compressed Hilar Bile Duct Induced by Perihilar Hyperplasia of Liver.
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Guangyu Chen, Feng Tian, Xin Zhao, Yan Chen, Tao Peng, Jingchi Cui, Dajiang Li, Yu He, and Shuguang Wang
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BILE ducts , *HEPATECTOMY , *LIVER , *HYPERPLASIA , *SURGICAL complications , *PORTAL vein surgery - Abstract
Background: Stone recurrence is a major problem limiting the effects of surgical treatment for hepatolithiasis. It was showed that hyperplasia of perihilar liver may compress the hepatic portal and cause deficient bile flow because of compressed hilar bile duct, thereby leading to the formation of bile stasis and precipitating stone recurrence. This retrospective study aimed to evaluate the efficiency of perihilar hepatectomy for hepatolithiasis with compressed hilar bile duct induced by perihilar hyperplasia of liver. Methods: 135 patients with compressed hilar bile duct induced by hypertrophied perihilar liver were included in this study from January 2011 to July 2016. Among these patients, 77 underwent conventional operation procedure (control group) and 58 underwent conventional operation procedure added by perihilar hepatectomy (perihilar hepatectomy group). Clinical data containing preoperative data, intraoperative data, operation complications, and short-term and long-term outcomes were collected. Results: The demographic and disease-related characteristics of the two groups were comparable. The two groups were not remarkably different in operationrelated characteristics. The incidence of bile leakage in the perihilar hepatectomy group was substantially higher than that in the control group. Other postoperative complications were not remarkably different between the two groups. In the long-term postoperative follow-up period, the incidence of the recurrence of stones and cholangitis in the control group was considerably higher than that in the perihilar hepatectomy group. Conclusions: Based on conventional operation procedure, additional perihilar hepatectomy is a reliable intervention with definite clinical effects for hepatolithiasis with compressed hilar bile duct induced by hypertrophied perihilar liver. [ABSTRACT FROM AUTHOR]
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- 2020
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45. Sideswiping Tropical Cyclones and Their Associated Precipitation over China.
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Feng, Tian, Ren, Fumin, Zhang, Da-Lin, Li, Guoping, Qiu, Wenyu, and Yang, Hui
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METEOROLOGICAL precipitation , *SCIENTIFIC community , *TCP/IP , *TROPICAL cyclones - Abstract
Tropical cyclone (TC) precipitation (TCP) has attracted considerable attention in recent decades because of its adverse socioeconomic impacts. In particular, considerable effort has been devoted to quantifying TCP and investigating the precipitation of TCs that make landfall. However, precipitation over land induced by TCs that do not make landfall (i.e., offshore), the so-called "sideswiping" TCs (STCs), is an important component of TCP but has attracted little attention from the research community to date. Here, best-track and daily precipitation data from the China Meteorological Administration during the 59 years of 1960–2018 are used to study STC precipitation (STP). Results show that: (i) the annual number of STCs fluctuates significantly from 3 to 17, with a mean frequency of 8.8 STCs per year; (ii) there are decreasing trends in STC frequency and STP amount over the past 59 years; (iii) both STC frequency and STP are high from July to October, with maxima in August; (iv) the distribution of STP, covering most of China's coastal regions, is dominated by intense STCs, and the annual STP decreases from southeast coastal regions to northwest inland areas, with a maximum value over the islands of Taiwan and Hainan; and (v) extreme STP events could appear not only over the island and coastal areas, but also over inland areas such as Zhumadian of Henan Province due to the influences of local orography and favorable large-scale forcing. [ABSTRACT FROM AUTHOR]
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- 2020
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46. Preparation and Kinetics of g‐C3N4/TiO2 Nanomaterials for the Photodegradation of Pyridine Under Solar‐Light Irradiation.
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Liu, Min, Feng Tian, Xue, and Long Chang, Yan
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PHOTODEGRADATION , *BAND gaps , *PYRIDINE , *SEWAGE purification , *INDUSTRIAL capacity , *IRRADIATION - Abstract
As a high‐efficient photocatalyst, g‐C3N4/TiO2 (PCN) was successfully prepared by thermal polymerization. In addition, the structure and morphological characteristics of the as‐prepared samples were investigated by XRD, BET, XPS, SEM, TEM, and UV‐vis DRS. The results revealed that in the presence of g‐C3N4, the physicochemical properties of the catalyst and the band gap of PCN decreased from 3.09 eV to 2.98 eV, clearly indicative of the enhanced photocatalytic performance relative to pure P25 or g‐C3N4 under sunlight. Furthermore, the photocatalytic properties of PCN were examined by the degradation of pyridine and other nitrogen heterocyclic pollutants under sunlight irradiation. Next, the main factors affecting the photocatalytic activity were investigated in detail, including the initial concentration of the pollutant, the mass of the photocatalyst, the initial pH of the solution, and the doping amount of g‐C3N4, as well as different free‐radical scavengers. On the other hand, the reusability of PCN demonstrated that photocatalysts exhibit outstanding photocatalytic stability after 10 cycles. Hence, high efficiency photocatalysts demonstrate potential for industrial applications such as sewage treatment. [ABSTRACT FROM AUTHOR]
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- 2020
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47. Simulation study on heat loss from long-distance vertical-buried pipes in cooling system of heat hazard mine.
- Author
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Gao, Tao, Yue, Feng-Tian, Sun, Meng, Wei, Jing-Sheng, and Wang, Yi-Jiang
- Abstract
In order to improve thermal and humid environment of the heat hazard mine, a ground cooling system is proposed. In the ground cooling system, the chilled water is transmitted to the air cooler in working face through long-distance vertical-buried pipes (LDVBP). Under this background, the simplified numerical heat transfer model between LDVBP and rock-soil layers is established to calculate the temperature rise and heat loss of the chilled water. Comparing the calculated results with the measured data in Wutongzhuang Coal Mine of Hebei province, the error is less than 5%. Furthermore, the numerical simulation results show the main influencing factors on heat loss of LDVBP are the heat transfer temperature difference of underground high- and low-pressure heat exchanger, flow rate, and inlet temperature of supply water when there is no groundwater seepage, which should be considered in ground cooling system design. In this study, the supply water temperature rise is 0.15°C and the comprehensive heat loss coefficient is less than 5.8%, which can meet the requirements of mine cooling engineering. [ABSTRACT FROM AUTHOR]
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- 2020
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48. The Effects of 12-Week Physical Exercise Tapping High-level Cognitive Functions.
- Author
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Ji, Zhiguang, Feng, Tian, and Wang, Hongbiao
- Abstract
The purpose of this study was to investigate the effects of physical exercise tapping high-level cognitive functions on both cognitive function and fitness in older adults. In total, 96 healthy older adults took part in the study. Participants were randomly assigned to four groups: a cognitive training group (CG), physical exercise group (PG), simultaneous cognitive training and physical exercise group (C+PG), and the healthy control group (HG; received physical exercise materials but did not participate in a cognitive or exercise programme). The outcomes were the changes in the 6-minute walk test (6MWT), timed up-and-go (TUG) test, and the computerized modified Stroop task, which included two conditions, a naming condition (nonexecutive) and an executive condition. The results showed that the dynamic balance, cardiorespiratory endurance, and physical activity levels of the PG and C+PG were significantly better than those of the HG after the 12-week intervention. The times of the TUG test in these two groups were also significantly faster than those in the HG. Additionally, the C+PG exhibited better dual-task function than the PG. Over 12 weeks, the CG, PG, and C+PG demonstrated improved performance of executive function, but only the C+PG showed a general facilitative effect on nonexecutive control. Physical exercise tapping high-level cognitive functions and cognitive training can thus improve executive function more quickly than physical exercise alone. Moreover, physical exercise tapping high-level cognitive functions showed better fitness improvement than cognitive training alone, especially in dynamic balance. [ABSTRACT FROM AUTHOR]
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- 2020
- Full Text
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49. The effects of sport expertise and shot results on basketball players' action anticipation.
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Li, Yawei and Feng, Tian
- Subjects
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BASKETBALL players , *EXPERTISE , *JUDGMENT (Psychology) , *SPORTS , *CROSS-sectional method , *JUDGMENT sampling - Abstract
The purpose of the present cross-sectional study was to clarify the effects of sport expertise and shot results on the action anticipation of basketball players. Eighty-eight male subjects participated in this study, namely, 30 collegiate basketball players, 28 recreational basketball players and 30 non-athletes. Each participant performed a shot anticipation task in which he watched the shooting phase, rising phase, high point and falling phase of a free throw and predicted the fate of the ball. The results showed that the collegiate players and recreational players demonstrated higher accuracy than the non-athletes for the falling phase but not for the other temporal conditions. Analysis of the shot results demonstrated that for made shots, the collegiate players and recreational players provided more accurate predictions than the non-athletes. These results suggested that the experienced players required a sufficient amount of information to be able to make accurate judgements and demonstrated that the experts' judgement bias for made shots was independent of the temporal condition. [ABSTRACT FROM AUTHOR]
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- 2020
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50. Effects of Upadacitinib Coadministration on the Pharmacokinetics of Sensitive Cytochrome P450 Probe Substrates: A Study With the Modified Cooperstown 5+1 Cocktail.
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Mohamed, Mohamed‐Eslam F., Feng, Tian, Enejosa, Jeffrey V., Fisniku, Ogert, and Othman, Ahmed A.
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CAFFEINE , *CLINICAL trials , *CONFIDENCE intervals , *DRUG interactions , *MIDAZOLAM , *NEUROTRANSMITTER uptake inhibitors , *OMEPRAZOLE , *RHEUMATOID arthritis , *VITAMIN K , *WARFARIN , *PHENOTYPES , *DEXTROMETHORPHAN , *DESCRIPTIVE statistics , *JANUS kinases , *IN vivo studies , *CYTOCHROME P-450 - Abstract
The aim of this study was to characterize the effects of upadacitinib, a Janus kinase 1 inhibitor, on in vivo activity of different cytochrome P450 (CYP) enzymes using a cocktail approach. Healthy subjects (n = 20) received single oral doses of the modified Cooperstown 5+1 cocktail drugs (midazolam [CYP3A], caffeine [CYP1A2], warfarin + vitamin K [CYP2C9], omeprazole [CYP2C19], and dextromethorphan [CYP2D6]) without upadacitinib and on day 11 (midazolam) or 12 (all other probes) of a 15‐day regimen of upadacitinib 30 mg once daily (extended‐release formulation). Serial blood samples and 12‐hour urine samples were collected for assays of the probe substrates and select metabolites. The ratio (90%CI) of area under the plasma concentration‐time curve from time 0 to infinity (AUCinf) central values when the cocktail drugs were administered with upadacitinib relative to when administered alone were 0.74 (0.68‐0.80) for midazolam, 1.22 (1.15‐1.29) for caffeine, 1.11 (1.07‐1.15) for S‐warfarin, 1.07 (0.95‐1.22) for dextromethorphan, and 0.82 (0.72‐0.94) for omeprazole. The ratio (90%CI) was 1.09 (1.00‐1.19) for 5‐hydroxy‐omeprazole to omeprazole AUCinf ratio and 1.17 (0.97‐1.41) for dextromethorphan to dextrorphan 12‐hour molar urinary ratio. Upadacitinib 30 mg once daily (a dose that is twice the optimal dose in rheumatoid arthritis based on phase 3 results) has a limited effect on CYP3A activity (26% decrease in exposure of midazolam, a sensitive CYP3A substrate) and no relevant effects on CYP1A2, CYP2C9, CYP2C19, or CYP2D6 activity in vivo. No clinically relevant changes in plasma exposures are expected for drugs that are substrates for the evaluated CYP enzymes when coadministered with upadacitinib. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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