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Effect of catalyst diesel particulate filter aging and catalyst loadings on particulate emission characteristics from a diesel vehicle

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Journal of Environmental Sciences 2024年第2期136卷 35-44页

作者： Yunhua Zhang Diming Lou Piqiang Tan Zhiyuan Hu liang fang School of Automotive Studies Tongji UniversityShanghai 201804China

In this study,the effect of new and used catalyzed diesel particulate filter(CDPF)with different catalyst loadings on the particulate emissions including the particle mass(PM),particle number(PN),particle size distribution(PSD)and geometric mean diameter(GMD)from a diesel vehicle were investigated based on a heavy chassis dynamometer.Results showed that more than 97.9%of the PN and 95.4%of the PM were reduced by the CDPF,and the reduction efficiency was enhanced by the catalyst loading.After using the CDPF,the PSD transformed from bimodal to trimodal with the peak shifting towards smaller particle size,more nucleation mode particles were reduced compared with accumulation mode ones,but the reduction effect on the accumulation mode particles was more significantly influenced by the catalyst loading.Notably,the CDPF increased the accumulation mode particles proportion,producing a larger GMD.For the used CDPF,its reduction effect on the particulate emissions enhanced,especially for the PM in accumulation mode.The PSD returned to bimodal,but the peak at accumulation mode began to be higher than that at nucleation mode,illustrating that more nucleation mode particles was removed.The aging of the CDPF resulted in greater effect on the PN-based PSD than that of PM-based PSD,but the effect of catalyst loading on the PN and PM emission factors was weakened.The used CDPF further increased the GMD,and the effect of catalyst loading on the GMD was strengthened,a higher catalyst loading led to a reduction in the GMD.

关键词： Catalyzed diesel particulate filter (CDPF) Catalyst loading Aging Particle Particle size distribution Geometric mean diameter

Uniqueness on Difference Operators of Meromorphic Functions of Infinite Order

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Acta Mathematica Sinica,English Series 2024年第2期40卷 511-527页

作者： Hui LI Ming liang fang Xiao YAO School of Science China University of Mining and TechnologyBeijing 100083P.R.China Institute of Mathematics Academy of Mathematics and System SciencesChinese Academy of SciencesBeijing 100190P.R.China School of Sciences Hangzhou Dianzi UniversityHangzhou 310012P.R.China School of Mathematical sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We investigate the uniqueness problems of meromorphic functions and their difference operators by using a new method.It is proved that if a non-constant meromorphic function f shares a non-zero constant and ∞ counting multiplicities with its difference operators Δcf(z) and Δ_(c)^(2)f(z), thenΔcf(z)≡Δ_(c)^(2)f(z).In particular,we give a difference analogue of a result of Jank-Mues-Volkmann.Our method has two distinct features:(ⅰ) It converts the relations between functions into the corresponding vectors.This makes it possible to deal with the uniqueness problem by linear algebra and combinatorics.(ⅱ) It circumvents the obstacle of the difference logarithmic derivative lemma for meromorphic functions of infinite order,since this method does not depend on the growth of the functions.Furthermore,the idea in this paper can also be applied to the case for several variables.

关键词： Uniqueness meromorphic functions difference operators infinite order

Blockade of the deubiquitinating enzyme USP48 degrades oncogenic HMGA2 and inhibits colorectal cancer invasion and metastasis

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Acta Pharmaceutica Sinica B 2024年第4期14卷 1624-1643页

作者： Can Cheng Hanhui Yao Heng Li Jingwen Liu Zhengyi Liu Yang Wu liang Zhu Hejie Hu Zhengdong fang liang Wu Department of General Surgery the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Comprehensive Surgery Anhui Provincial Cancer HospitalWest District of the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Anhui Provincial Hospital Health Management Center the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001China Department of Breast Surgery Henan Provincial People's HospitalPeople's Hospital of Zhengzhou UniversityPeople's Hospital of Henan UniversityZhengzhou 450003China

HMGA2,a pivotal transcription factor,functions as a versatile regulator implicated in the progression of diverse aggressive malignancies.In this study,mass spectrometry was employed to identify ubiquitin-specific proteases that potentially interact with HMGA2,and USP48 was identified as a deubiquitinating enzyme of HMGA2.The enforced expression of USP48 significantly increased HMGA2 protein levels by inhibiting its degradation,while the deprivation of USP48 promoted HMGA2 degradation,thereby suppressing tumor invasion and metastasis.We discovered that USP48 undergoes SUMOylation at lysine 258,which enhances its binding affinity to HMGA2.Through subsequent phenotypic screening of small molecules,we identified DUB-IN-2 as a remarkably potent pharmacological inhibitor of USP48.Interestingly,the small-molecule inhibitor targeting USP48 induces destabilization of HMGA2.Clinically,upregulation of USP48 or HMGA2 in cancerous tissues is indicative of poor prognosis for patients with colorectal cancer(CRC).Collectively,our study not only elucidates the regulatory mechanism of DUBs involved in HMGA2 stability and validates USP48 as a potential therapeutic target for CRC,but also identifies DUB-IN-2 as a potent inhibitor of USP48 and a promising candidate for CRC treatment.

关键词： Colorectal cancer Invasion and metastasis Post-translational modification Ubiquitination SUMOylation USP48 HMGA2 Specific inhibitors

What can we learn from recent 2νββexperiments?

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Chinese Physics C 2024年第3期48卷 93-103页

作者：房栋梁 Institute of Modern Physics Chinese Academy of sciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Recent measurements of the two neutrino double beta decay high precision electron spectra,combined with charge exchange orβ-decay experimental data,have revealed severe constraints across current nuclear many body calculations.Our calculations show that the quasi-particle random phase approximation(QRPA)approach can adequately reproduce the measured spectra for the two open shell nuclei,^(82)Se and ^(100)Mo.For the closed shell nucleus ^(136)Xe,QRPA can also reproduce the spectra with proper treatments.Considering the high-lying state reduction,we also find that the nuclear shell model can also adequately reproduce the spectra and Gamow-Teller transition strength under a unique quenched axial-vector coupling constant gA.For ^(136)Xe,we find that flipping the sign for the decay strength causes the spectra to go beyond the so-called high-lying state dominance hypothesis.These results call for future high precision measurements of charge-exchange reactions.

关键词： nuclear stucture double beta decay electron spectra

Targeting oxidative stress with natural products: A novel strategy for esophageal cancer therapy

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 287-299页

作者： fang Cao Han-Ling Zhang Cui Guo Xue-liang Xu Qiang Yuan Department of Rehabilitation III Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Rehabilitation Chongqing Fuling District Maternal and Child Health HospitalChongqing 408000China Department of Rehabilitation Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina

Esophageal cancer(ESC)is a malignant tumor that originates from the mucosal epithelium of the esophagus and is part of the digestive tract.Although the exact pathogenesis of ESC has not been fully elucidated,excessive oxidative stress is an important characteristic that leads to the development of many cancers.Abnormal expression of several proteins and transcription factors contributes to oxidative stress in ESCs,which alters the growth and proliferation of ESCs and promotes their metastasis.Natural compounds,including alkaloids,terpenes,polyphenols,and xanthine compounds,can inhibit reactive oxygen species production in ESCs.These compounds reduce oxidative stress levels and subsequently inhibit the oc-currence and progression of ESC through the regulation of targets and pathways such as the cytokine interleukins 6 and 10,superoxide dismutase,the NF-+ACY-kappa+ADs-B/MAPK pathway,and the mammalian Nrf2/ARE target pathway.Thus,targeting tumor oxidative stress has become a key focus in anti-ESC therapy.This review discusses the potential of Natural products(NPs)for treating ESCs and summarizes the application prospects of oxidative stress as a new target for ESC treatment.The findings of this review provide a reference for drug development targeting ESCs.Nonetheless,further high-quality studies will be necessary to determine the clinical efficacy of these various NPs.

关键词： Oxidative stress Natural products Esophageal cancer Reactive oxygen species

Characteristics,origins,and significance of pyrites in deep-water shales

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Science China Earth Sciences 2024年第2期67卷 313-342页

作者： Chao liang Shichao JI Yingchang CAO Keyu LIU Jing WU fang HAO National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580China School of Geosciences China University of PetroleumQingdao266000China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao266071China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China

As important metal sulfides in the geochemical cycle of sulfur,the characteristics and formation processes of pyrites can provide useful clues regarding their environment.Based on previous findings,shale pyrites were divided into three major classes(euhedral pyrites,framboidal pyrites(framboids)and metasomatic pyrites)and six sub-classes in this study.At the microscopic scale,each type of pyrite is associated with a different formation process.Framboids are formed by burst nucleation in environments with a homogeneous distribution of nutrients while euhedral pyrites are usually formed on pre-existing sites(such as=FeS on the minerals surface)in the heterogeneous system.Metasomatic pyrites formed by the replacement of other ions in accountable material by iron ions and hydrogen sulfide ions in hydrothermal events.The morphology and isotope value of pyrite provide information to track the origins of their nutrient and characteristics of sulfur and iron pools.In addition,the trace element content of pyrite can serve as a proxy for paleo-ocean trace element abundance,indicating changes in atmospheric oxygen content.Additionally,pyrite can also serves as an indicator of shale gas reservoirs.

关键词： Shale Pyrite Sulfate reduction reaction Isotope fractionation Pyrite element

Efficacy of scleral buckling for the treatment of rhegmatogenous retinal detachment using a novel foldable capsular buckle

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 558-563页

作者： fang-fang Fan Chang Xiao liang Wang Xin-Ting Wang Dan-Dan Liu Xing Ge Ya-Lu Liu Su-Yan Li The Affiliated Xuzhou Municipal Hospital of Xuzhou Medical University Xuzhou 221000Jiangsu ProvinceChina Department of Ophthalmology Xuzhou First People’s HospitalXuzhou 221116Jiangsu ProvinceChina Eye Disease Prevention and Treatment Institute of Xuzhou Xuzhou 221116Jiangsu ProvinceChina The Affiliated Shuyang Hospital of Xuzhou Medical University Shuyang 223600Jiangsu ProvinceChina

●AIM:To evaluate the effectiveness and safety of scleral buckling for the treatment of rhegmatogenous retinal detachment(RRD)using a novel foldable capsular buckle(FCB).●METHODS:This was a series of case observation studies.Eighteen patients(18 eyes)who visited our ophthalmology department between August 2020 and August 2022 and were treated for RRD with scleral buckling using FCB were included.The procedure was similar to conventional scleral buckling,while a balloon-like FCB was placed onto the retinal break with balanced salt solution filling for a broad,external indentation instead of the silicone buckle.The retinal reattachment rate,best corrected visual acuity(BCVA),intraocular pressure(IOP),refractive dioptre and astigmatism degree,and complications were evaluated and recorded.●RESULTS:There were 7 males and 11 females aged 19-58y.The average time course of RRD was 12d,ranging from 7-20d.The retinal break was located in the superior quadrants in 8 eyes and in the inferior quadrants in 10 eyes,with macula-off detachments in 12 eyes.The patients were followed-up for at least 6mo.The final retinal reattachment rate was 100%.The BCVA was significantly improved compared with the baseline(P0.05).Three patients had transiently high IOPs within one week after surgery.Mild diplopia occurred in 5 patients after surgery and then disappeared after the balloon fluid was removed.●CONCLUSION:The success rate of FCB scleral buckling for RRD is satisfactory.This procedure can be expected to be applied in new,uncomplicated cases of RRD.

关键词： rhegmatogenous retinal detachment scleral buckling foldable capsular buckle

A Novel Fracturing Fluid with High-Temperature Resistance for Ultra-Deep Reservoirs

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Fluid Dynamics & Materials Processing 2024年第5期20卷 975-987页

作者： Lian Liu liang Li Kebo Jiao Junwei fang Yun Luo Northwest Oilfield Branch China Petroleum&Chemical CorporationUrumqi830011China Sinopec Key Laboratory for Enhanced Recovery in Fractured and Cavernous Reservoir Urumqi830011China

Ultra-deep reservoirs play an important role at present in fossil energy exploitation.Due to the related high temperature,high pressure,and high formation fracture pressure,however,methods for oil well stimulation do not produce satisfactory results when conventional fracturing fluids with a low pumping rate are used.In response to the above problem,a fracturing fluid with a density of 1.2~1.4 g/cm^(3)was developed by using Potassium formatted,hydroxypropyl guanidine gum and zirconium crosslinking agents.The fracturing fluid was tested and its ability to maintain a viscosity of 100 mPa.s over more than 60 min was verified under a shear rate of 1701/s and at a temperature of 175℃.This fluid has good sand-carrying performances,a low viscosity after breaking the rubber,and the residue content is less than 200 mg/L.Compared with ordinary reconstruction fluid,it can increase the density by 30%~40%and reduce the wellhead pressure of 8000 m level reconstruction wells.Moreover,the new fracturing fluid can significantly mitigate safety risks.

关键词： Ultra-deep reservoir high-temperature resistance weighted fracturing fluid guanidine gum potassium formatted

Fight or flee,a vital choice for Clostridioides difficile

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mLife 2024年第1期3卷 14-20页

作者： Ji Zeng Sshuying fang Jinquan Guo Min Dong Guo-Bao Tian liang Tao School of Biomedical and Pharmaceutical Sciences Guangdong University of TechnologyGuangzhouChina Department of Brest Surgery Panyu Central Hospital.GuangzhouChina Department of Microbiology Harvard Medical SchoolBostonMassachusettsUSA Department of Urology Boston Children's HospitalHarvard Medical SchoolBostonMassachusettsUSA Department of Microbiology Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouChina Advanced Medical Technology Center The First Affiliated HospitalZhongshan School of MedicineSun Yat-sen UniversityGuangzhouChina Key Laboratory of Tropical Diseases Control(Sun Yat-sen University) Ministry of EducationGuangzhouChina School of Medicine Xizang Minzu UniversityXianyangChina Center for Infectious Disease Research Westlake Laboratory of Life Sciences and BiomedicineWestlake UniversityHangzhouChina Research Center for Industries of the Future School of Life SciencesWestlake UniversityHangzhouChina

Clostridioides difficile is a leading cause of healthcare-associated infections,causing billions of economic losses every year.Its symptoms range from mild diarrhea to life-threatening damage to the colon.Transmission and recurrence of c.difficile infection(CDl)are mediated by the metabolically dormant spores,while the virulence of C.difficile is mainly due to the two large clostridial toxins,TcdA and TcdB.Producing toxins or forming spores are two different strategies for C.difficile to cope with harsh environmental conditions.It is of great significance to understand the molecular mechanisms for C.difficile to skew to either of the cellular processes.Here,we summarize the current understanding of the regulation and connections between toxin production and sporulation in C.difficile and further discuss the potential solutions for yet-to-be-answered questions.

关键词： C.difficile sporulation TcdA TcdB toxin production