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Rational molecular design of efficient yellow-red dendrimer TADF for solution-processed OLEDs: a combined effect of substitution position and strength of the donors

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Science China Chemistry 2024年第5期67卷 1613-1623页

作者： Changfeng si Dianming Sun Tomas Matulaitis David B.Cordes Alexandra M.z.Slawin Eli zysman-Colman Organic Semiconductor Centre EaStCHEM School of ChemistryUniversity of St AndrewsSt AndrewsKY169STUK

The development of high-performance solution-processed red organic light-emitting diodes(OLEDs) remains a challenge,particularly in terms of maintaining efficiency at high luminance. Here, we designed and synthesized four novel orange-red thermally activated delayed fluorescence(TADF) dendrimers that are solution-processable: 2GCz Bp, 2DpACz Bp, 2FBp2GCz and 2FBp2DpACz. We systematically investigated the effect of substitution position and strength of donors on the optoelectronic properties. The reverse intersystem crossing rate constant(kRISC) of the emitters having donors substituted at positions 11and 12 of the dibenzo[a,c]phenazine(Bp) is more than 10-times faster than that of compounds substituted having donors substituted at positions 3 and 6. Compound 2DpACz Bp, containing stronger donors than 2GCz Bp, exhibits a red-shifted emission and smaller singlet-triplet energy splitting, ΔE_(ST), of 0.01 e V. The solution-processed OLED with 10 wt% 2DpACz Bp doped in m Cp emitted at 640 nm and showed a maximum external quantum efficiency(EQE_(max)) of 7.8%, which was effectively maintained out to a luminance of 1,000 cd m-2. Such a device's performance at relevant display luminance is among the highest for solution-processed red TADF OLEDs. The efficiency of the devices was improved significantly by using 4Cz IpN as an assistant dopant in a hyperfluorescence(HF) configuration, where the 2DpACz Bp HF device shows an EQEmaxof 20.0% at λEL of 605 nm and remains high at 11.8% at a luminance of 1,000 cd m-2, which makes this device one of the highest efficiency orange-to-red HF Sp-OLEDs to date.

关键词： thermally activated delayed fluorescence solution-processing red OLEDs dibenzo[a,c]phenazine dendrimers

Design and tailoring of patterned znO nanostructures for perovskite light absorption modulation

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 855-861页

作者： Haonan si Xuan zhao Qingliang Liao Yue zhang Academy for Advanced Interdisciplinary Science and Technology Beijing Advanced Innovation Center for Materials Genome EngineeringUniversity of Science and Technology BeijingBeijing 100083China Key Laboratory of Advanced Materials and Devices for post-Moore Chips Ministry of EducationBeijing Key Laboratory for Advanced Energy Materials and TechnologiesSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Lithography is a pivotal micro/nanomanufacturing technique,facilitating performance enhancements in an extensive array of devices,encompassing sensors,transistors,and photovoltaic *** key to creating highly precise,multiscale-distributed patterned structures is the precise control of the lithography ***,high-quality patterned znO nanostructures are constructed by systematically tuning the exposure and development times during *** optimizing these parameters,znO nanorod arrays with line/hole arrangements are successfully *** znO nanostructures with highly controllable morphology and structure possess discrete three-dimensional space structure,enlarged surface area,and improved light capture ability,which achieve highly efficient energy conversion in perovskite solar *** lithography process management for these patterned znO nanostructures provides important guidance for the design and construction of complex nanostructures and devices with excellent performance.

关键词： lithography patterned znO nanorod arrays light absorption perovskite solar cell

Quantification of perfluorinated compounds in atmospheric particulate shows potential connection with environmental event

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Journal of Environmental Sciences 2024年第2期136卷 237-247页

作者： Hua Tang Ying Wang Shengling si Hongli Li David Da Yong Chen National Institute of Metrology 18 BeisanhuandongluChaoyang DistrictBeijing 100029China School of Chemistry and Materials Science Nanjing Normal UniversityNanjing 210023China si Chuan zhong Ce Biao Wu Technology Co.Ltd. Sichuan 610052China Department of Chemistry University of British ColumbiaVancouver V6T 1Z1BCCanada

A method of quantification of perfluorinated compounds(pFCs)from atmospheric particulate matter(ApM)is described.A single step pretreatment method,selective pressurized liquid extraction(SpLE),was developed to reduce the high matrix background and avoid contamination from commonly used multiple sample pretreatment *** effective sorbent was selected to purify the pFCs during SpLE,followed by liquid chromatography-tandem mass spectrometry(LC–MS/MS),for quantification of *** affecting the SpLE efficiency,including temperature,static extraction time,and number of extraction cycles used,were *** optimum conditions were found to be 120℃,10 min,and 3 cycles,***-MS/MS method was developed to obtain the optimal sensitivity specific to *** method detection limits(MDLs)were 0.006 to 0.48 ng/g for the pFCs studied and the linear response range was from 0.1 to 100 ng/*** ensure accurate values were obtained,each step of the experiment was evaluated and controlled to prevent *** optimized method was tested by performing spiking experiments in natural particulate matter matrices and good rates of recovery and reproducibility were obtained for all target ***,the method was successfully used to measure 16 pFCs in the ApM samples collected in Beijing over five years from 2015 to *** is observed that some pFCs follow the trend of total pFC changes,and can be attributed to the environment influencing events and policy enforcement,while others don't seem to change as much with time of the year or from year to year.

关键词： Selective pressurized liquid extraction Liquid chromatography-mass spectrometry perfluorinated compounds Atmospheric particulate matter pollution control

phenomenology of heavy neutral gauge boson at muon collider

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Science China(physics,Mechanics & Astronomy) 2024年第3期67卷 60-79页

作者： zongyang Lu Honglei Li zhi-Long Han zong-Guo si Liuxin zhao School of physics and Technology University of JinanJinan 250022China School of physics Shandong UniversityJinan 250100China

Heavy neutral gauge boson z' is proposed in many new physics *** has rich phenomena at the future muon *** study the properties of z' boson with the process of μ^(+)μ^(-)→qq,μ^(+)μ^(-)→l^(+)l^(-),μ^(+)μ^(-)→ zH and μ^(+)μ^(-)→ W^(+)W^(-).The discrepancy of z' coupling to different types of particles can be shown in the cross section distributions around the resonance peak of various decay *** distributions of the final quark or lepton in μ^(+)μ^(-)→qq/l^(+)l^(-)process are sensitive to the parameters such as mass of z' and the z-z' mixing *** interaction of new gauge boson coupling to the standard model gauge particles and Higgs boson are also studied through μ^(+)μ^(-)→ zH→l^(+)l^(-)bb and μ^(+)u^(-)→ W^(+)W^(-)→l^(+)l^(-)v_(l)v_(l).The cross section and the final particles' angular distributions with the contribution of z' boson differ from those processes with only standard model particles.A forward-backward asymmetry defined by the angular distribution is provided to show the potential of searching for new physics at the muon ***,the beam polarization with certain value can effectively enlarge the forward-backward asymmetry.

关键词： z′boson muon collider new physics

Anion exchange membranes with a semi-interpenetrating polymer network using 1,6-dibromohexane as bifunctional crosslinker

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Chinese Journal of Chemical Engineering 2024年第8期72卷 199-208页

作者： Aijie Li zhanliang Wang zhihao si Lu Lu peipei Huang Jinhong Liu Songyuan Yao peiyong Qin Xinmiao zhang National Energy R&D Center for Biorefinery College of Life Science and TechnologyBeijing University of Chemical TechnologyBeijing 100029China paris Curie Engineer School Beijing University of Chemical TechnologyBeijing 100029China Environmental protection Research Institute Beijing Research Institute of Chemical IndustryBeijing 100000China

An anion exchange membrane(AEM)is generally expected to possess high ion exchange capacity(IEC),low water uptake(WU),and high mechanical strength when applied to electrodialysis *** different types of AEMs,semi-interpenetrating polymer networks(sipNs)have been suggested for their structural superiorities,i.e.,the tunable local density of ion exchange groups for IEC and the restrained leaching of hygroscopic groups by insolubility for ***,the conventional sipN AEMs still struggle to balances IEC,WU,and mechanical strength simultaneously,due to the lack of the compact crosslinking *** this work,we proposed a novel sipN structure of polyvinylidene difluoride/polyvinylimidazole/1,6-dibromohexane(pVDF/pVIm/DBH).On the one hand,DBH with two cationic groups of imidazole groups are introduced to enhance the ion conductivity,which is different from the conventional monofunctional modifier with only one cationic *** the other hand,DBH has the ability to bridge with pVIm,where the mechanical strength of the resulting AEM is increased by the increase of crosslinking *** show that a low WU of 38.1%to 62.6%,high IEC of 2.12—2.22 mmol·g^(-1),and excellent tensile strength of 3.54—12.35 Mpa for pVDF/pVIm/DBH membrane are *** work opens a new avenue for achieving the high-quality AEMs.

关键词： Anion exchange membrane polyvinylidene difluoride Electrodialysis Semi-interpenetrating polymer networks

Ultrasound blood flow characteristics changes in fetal umbilical artery thrombosis:A retrospective analysis

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World Journal of Clinical Cases 2024年第2期12卷 240-248页

作者： si-Jie Hong Li-Wei Hong Xiao-Qin He Xiao-Hong zhong Department of Ultrasound Women and Children's HospitalSchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina Ministry of Science and Education Women and Children's HospitalSchool of MedicineXiamen UniversityXiamen 361000Fujian ProvinceChina

BACKGROUND Umbilical artery thrombosis(UAT)is extremely uncommon and leads to adverse perinatal *** of blood in pregnant women is suspected to be an important risk for *** is an effective way to detect *** mother can monitor her own fetal health using ultrasound,which enables her to take preventative action in case of *** To investigate ultrasonic blood signal after UAT in the umbilical artery,and evaluate the relationship between hypercoagulability and *** We described a case of a newly formed UAT with markedly altered ultrasonic indices of umbilical artery blood flow,and retrospectively studied it with 18 UAT patients confirmed by histopathology from October 2019 and March 2023 in Xiamen Women and Children's ***’information was collected from medical archives,including maternal clinical data,neonatal outcomes,pathological findings and ultrasonic indices of umbilical artery blood flow,such as systolic-diastolic duration ratio(S/D),resistance index(RI),pulsatility index(pI)and peak systolic velocity(pSV).Ultrasound and coagulation indices were analyzed with matched samples t-test and Wilcoxon rank sum test using the statistical packages in R(version 4.2.1)including car(version 3.1-0)and stats(version 4.2.1),and visualized by ggplot2 package(version 3.3.6).RESULTS A patient with normal findings in second and third-trimester routine ultrasound scan developed UAT with severe changes in ultrasonic indices of umbilical artery blood flow(within 2.5th of reference ranges)in a short period of *** analysis of umbilical artery blood flow ultrasound indices for 19 patients with UAT showed that the decrease in S/D,RI,and pI and increase of pSV during the disease process was greater than that of *** 18 patients delivered in our hospital showed characteristic manifestations of UAT on histological examination after delivery,most of which(16/18)showed umbilical cord abnormalities,with 1

关键词： Umbilical artery thrombosis Obstetric ultrasonography peak systolic velocity Hypercoagulation Umbilical cord abnormalities Fetus

MAVS Antagonizes Human Stem Cell Senescence as a Mitochondrial Stabilizer

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Research 2024年第2期2023卷 239-257页

作者： Cui Wang Kuan Yang Xiaoqian Liu si Wang Moshi Song Juan Carlos Izpisua Belimonte Jing Qu Guang-Hui Liu Weiqi zhang CAS Key Laboratory of Genomic and precision Medicine Beijng Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China sino-Danish College University of Chinese Academy of SciencesBeijing 101408China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of Sciences Beijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Bejing 100101China Advanced Innovation Center for Human Brain protection National Clinical Research Center for Geriatric DisordersXuanwu Hospital Capital Medical UniversityBeijing 100053China State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Altos Labs Inc.San DiegoCA 94022USA

Mitochondrial dysfunction is a hallmark feature of cellular senescence and organ ***,we asked whether the mitochondrial antiviral signaling protein(MAVS),which is essential for driving antiviral response,also regulates human stem cell *** answer this question,we used CRISpR/Cas9-mediated gene editing and directed differentiation techniques to generate various MAVS-knockout human stem cell *** found that human mesenchymal stem cells(hMSCs)were sensitive to MAVS deficiency,as manifested by accelerated senescence *** uncovered that the role of MAVS in maintaining mitochondrial structural integrity and functional homeostasis depends on its interaction with the guanosine triphosphatase optic atrophy type 1(OpA1).Depletion of MAVS or OpA1 led to the dysfunction of mitochondria and cellular senescence,whereas replenishment of MAVS or OpA1 in MAVS-knockout hMSCs alleviated mitochondrial defects and premature senescence *** together,our data underscore an uncanonical role of MAVS in safeguarding mitochondrial homeostasis and antagonizing human stem cell senescence.

关键词： CRISpR/Cas9 homeostasis Mitochondrial

Epidemiology and prognostic nomogram for locally advanced gastric signet ring cell carcinoma:A population-based study

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2610-2630页

作者： ze-Hao Yu Lei-Ming zhang zhi-Qi Dai Meng-Na zhang si-Ming zheng Health Science Center The First Affiliated Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina Health Science Center Ningbo UniversityNingbo 315211Zhejiang ProvinceChina College of Medicine The First Affiliated Hospital of Zhejiang UniversityHangzhou 310058Zhejiang ProvinceChina

BACKGROUND Gastric signet ring cell carcinoma(GSRC)represents a specific subtype of gastric cancer renowned for its contentious epidemiological features,treatment principles,and prognostic *** To investigate the epidemiology of GSRC and establish an improved model for predicting the prognosis of patients with locally advanced GSRC(LAGSRC)after *** The annual rates of GSRC incidence and mortality,covering the years 1975 to 2019,were extracted from the Surveillance,Epidemiology,and End Results(SEER)database to explore the temporal trends in both disease incidence and mortality rates using Joinpoint *** clinical data of 3793 postoperative LAGSRC patients were collected from the SEER database for the analysis of survival *** Cox regression model was used to explore the independent prognostic factors for overall survival(OS).The risk factors extracted were used to establish a prognostic *** The overall incidence of GSRC increased dramatically between 1975 and 1998,followed by a significant downward trend in incidence after *** recent years,there has been a similarly optimistic trend in GSRC mortality *** trend in GSRC showed discrepancies based on age and *** operating characteristic curves,calibration curves,and decision curve analysis for 1-year,3-year,and 5-year OS demonstrated the high discriminative ability and clinical utility of this *** area under the curve indicated that the performance of the new model outperformed that of the pathological staging *** The model we established can aid clinicians in the early prognostication of LAGSRC patients,resulting in improved clinical outcomes by modifying management strategies and patient health care.

关键词： signet ring cell carcinoma Locally advanced gastric cancer Adjuvant chemotherapy Nomogram Epidemiology Overall survival

Safety and efficiency of Wharton’s Jelly-derived mesenchymal stem cell administration in patients with traumatic brain injury:First results of a phase I study

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World Journal of Stem Cells 2024年第6期16卷 641-655页

作者： Serdar Kabatas ErdinçCivelek Osman Boyalı Gülseli Berivan Sezen Omer Ozdemir Yeliz Bahar-Ozdemir Necati Kaplan Eyüp Can Savrunlu Erdal Karaöz Department of Neurosurgery University of Health Sciences TurkeyGaziosmanpaşa Training and Research HospitalIstanbul 34360Türkiye Center for Stem Cell&Gene Therapy Research and practice University of Health Sciences TurkeyIstanbul 34255Türkiye Department of Neurosurgery University of Health SciencesGaziosmanpaşa Training and Research HospitalIstanbul 34255Türkiye Department of physical Medicine and Rehabilitation Health Sciences University Sultan Abdulhamid Han Training and Research HospitalIstanbul 34668Türkiye Department of Neurosurgery Istanbul Rumeli UniversityÇorlu Reyap HospitalTekirdağ59860Türkiye Department of Neurosurgery Nevşehir State HospitalNevşehir 50300Türkiye Center for Regenerative Medicine and Stem Cell Research&Manufacturing(LivMedCell) Liv HospitalIstanbul 34340Türkiye Department of Histology and Embryology Istinye UniversityFaculty of MedicineIstanbul 34010Türkiye Center for Stem Cell and Tissue Engineering Research and practice Istinye UniversityIstanbul 34340Türkiye

BACKGROUND Traumatic brain injury(TBI)is characterized by a disruption in the normal function of the brain due to an injury following a trauma,which can potentially cause severe physical,cognitive,and emotional *** cell transplantation has evolved as a novel treatment modality in the management of TBI,as it has the potential to arrest the degeneration and promote regeneration of new cells in the ***’s Jelly-derived mesenchymal stem cells(WJ-MSCs)have recently shown beneficial effects in the functional recovery of neurological *** To evaluate the safety and efficiency of MSC therapy in *** We present 6 patients,4 male and 2 female aged between 21 and 27 years who suffered a *** 6 patients underwent 6 doses of intrathecal,intramuscular(i.m.)and intravenous transplantation of WJ-MSCs at a target dose of 1×106/kg for each application *** was assessed using the Modified Ashworth scale(MAS),motor function according to the Medical Research Council Muscle Strength Scale,quality of life was assessed by the Functional Independence Measure(FIM)scale and Karnofsky performance Status *** Our patients showed only early,transient complications,such as subfebrile fever,mild headache,and muscle pain due to ***,which resolved within 24 *** the one year follow-up,no other safety issues or adverse events were *** 6 patients showed improvements in their cognitive abilities,muscle spasticity,muscle strength,performance scores and fine motor skills when compared before and after the *** values,which we used to assess spasticity,were observed to statistically significantly decrease for both left and right sides(pppsignificant increase in pretest posttest *** difference observed in the participants’Karnofsky performance Scale values pre and post the intervention was statistically si

关键词： Traumatic brain injury Wharton Jelly Stem cell therapy Transplantation Mesenchymal stem cell