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Pt-Ni core-shell structure with Pt-skin and electronic effect on catalytic performance
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作者 Chong Yao dandan ma +9 位作者 Jie Luo Yixin Chen Min Tian Haoxuan Xie Chunshan Lu Feng Feng Xiaoliang Xu Qingtao Wang Qunfeng Zhang Xiaonian Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第11期260-267,共8页
In order to improve the catalytic performance of the nitrobenzene hydrogenation rearrangement to prepare p-aminophenol,a bimetallic Pt-Ni/C(PNC)catalyst was synthesized.Taking advantage of the synergistic effect of Ni... In order to improve the catalytic performance of the nitrobenzene hydrogenation rearrangement to prepare p-aminophenol,a bimetallic Pt-Ni/C(PNC)catalyst was synthesized.Taking advantage of the synergistic effect of Ni and Pt to enhance product selectivity and catalytic performance stability,the electrons in Ni are moved to Pt by the electron effect,which affects the catalyst’s ability to activate H_(2)as well as the amount of hydrogen activated.Furthermore,due to the strong Pt(5d)-Ni(3d)coupling effect,Ni can effectively maintain Pt stability in the acidic system and reduce Pt dissolution.The stability of the PNC can be found to be greatly enhanced compared to the Pt/C(PC)catalyst,and p-aminophenol selectivity is greatly enhanced,showing excellent catalytic performance. 展开更多
关键词 NITROBENZENE P-AMINOPHENOL Pt-Ni/C bimetallic catalyst Electronic effect Pt(5d)-Ni(3d)coupling
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Phlorizin alleviates deltamethrin-induced oxidative stress in brine shrimp Artemia
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作者 dandan ma Qingli ZHOU +5 位作者 Liying SUI Qingbin GUO Huanhuan LIU Honghe LIANG Zhenjing LI Zhongna SANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期163-173,共11页
Deltamethrin(DEL),a commonly used pyrethroid pesticide,results in higher reactive oxygen species(ROS)levels in aquatic animals,which consequently unbalance the redox state.Phlorizin(PHL)is a flavonoid and a natural pr... Deltamethrin(DEL),a commonly used pyrethroid pesticide,results in higher reactive oxygen species(ROS)levels in aquatic animals,which consequently unbalance the redox state.Phlorizin(PHL)is a flavonoid and a natural product promising to prevent or reduce pesticide-induced oxidative stress.Artemia is a micro-crustacean widely used in marine hatcheries and an experimental aquatic organism for environmental toxicology research.This research aimed to evaluate the toxicity of DEL on Artemia and the antioxidative effect of PHL against the toxicity.Results show that 0.08-mg/mL PHL exerted its antioxidative effects on hatching percentage of the cysts in 24-h incubation and on body length and survival rate of Artemia in 12-d culture.After 12-d culture,12-,24-,and 36-h DEL exposure showed significant drops in SOD,CAT,and GSH-Px enzyme activities,and significant increases in ROS and malondialdehyde(MDA)levels in Artemia(P<0.05).On the contrary,0.08-mg/mL PHL application improved the enzyme activities and decreased the ROS and MDA levels(P<0.05).Moreover,0.08-mg/mL PHL significantly increased mRNA expression levels of Cu/Zn SOD,CAT,GST,HO-1,NQO1,and Nrf2,and decreased mRNA expression level of Keap1 in the DEL-exposed Artemia(P<0.05).Therefore,DEL is toxic to Artemia,while PHL alleviates DEL-induced oxidative damage by possibly regulating the Nrf2signaling pathway.This study provided a theoretical basis for PHL to reduce pesticide-induced toxicity in aquatic animals. 展开更多
关键词 ARTEMIA DELTAMETHRIN PHLORIZIN oxidative stress
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GPCR/endocytosis/ERK signaling/S2R is involved in the regulation of the internalization,mitochondria-targeting and-activating properties of human salivary histatin 1
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作者 dandan ma Wei Sun +6 位作者 Cuicui Fu Kamran Nazmi Enno C.I.Veerman Richard T.Jaspers Jan G.M.Bolscher Floris J.Bikker Gang Wu 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第3期334-348,共15页
Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets an... Human salivary histatin 1(Hst1)exhibits a series of cell-activating properties,such as promoting cell spreading,migration,and metabolic activity.We recently have shown that fluorescently labeled Hst1(F-Hst1)targets and activates mitochondria,presenting an important molecular mechanism.However,its regulating signaling pathways remain to be elucidated.We investigated the influence of specific inhibitors of G protein-coupled receptors(GPCR),endocytosis pathways,extracellular signal-regulated kinases1/2(ERK1/2)signaling,p38 signaling,mitochondrial respiration and Na+/K+-ATPase activity on the uptake,mitochondria-targeting and-activating properties of F-Hst1.We performed a si RNA knockdown(KD)to assess the effect of Sigma-2 receptor(S2R)/Transmembrane Protein 97(TMEM97)—a recently identified target protein of Hst1.We also adopted live cell imaging to monitor the whole intracellular trafficking process of F-Hst1.Our results showed that the inhibition of cellular respiration hindered the internalization of F-Hst1.The inhibitors of GPCR,ERK1/2,phagocytosis,and clathrin-mediated endocytosis(CME)as well as siRNA KD of S2R/TMEM97 significantly reduced the uptake,which was accompanied by the nullification of the promoting effect of F-Hst1 on cell metabolic activity.Only the inhibitor of CME and KD of S2R/TMEM97 significantly compromised the mitochondria-targeting of Hst1.We further showed the intracellular trafficking and targeting process of F-Hst1,in which early endosome plays an important role.Overall,phagocytosis,CME,GPCR,ERK signaling,and S2R/TMEM97 are involved in the internalization of Hst1,while only CME and S2R/TMEM97 are critical for its subcellular targeting.The inhibition of either internalization or mitochondria-targeting of Hst1 could significantly compromise its mitochondria-activating property. 展开更多
关键词 GPCR/endocytosis/ERK signaling/S2R is involved in the regulation of the internalization mitochondria-targeting and activating properties of human salivary histatin 1 ERK
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静电纺丝法制备的CdS/ZnS/ZnO三元异质结纳米纤维无助催化剂下的光催化产氢性能 被引量:5
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作者 孙殿坤 石建稳 +5 位作者 马丹丹 邹雅珺 孙国太 毛思鳗 孙吕伟 成永红 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第9期1421-1429,共9页
近年来,由三种半导体组成的三元异质结由于其在促进光生电子和空穴的分离和转移方面的优势而备受关注.在本研究中,我们首先通过静电纺丝技术制备了Zn O纳米纤维,然后对其进行原位硫化,Zn O纳米纤维的表层被硫化成Zn S,得到Zn S/Zn O二... 近年来,由三种半导体组成的三元异质结由于其在促进光生电子和空穴的分离和转移方面的优势而备受关注.在本研究中,我们首先通过静电纺丝技术制备了Zn O纳米纤维,然后对其进行原位硫化,Zn O纳米纤维的表层被硫化成Zn S,得到Zn S/Zn O二元异质结纳米纤维,最后采用连续离子层吸附反应法在Zn S/Zn O纳米纤维上沉积Cd S量子点,得到Cd S/Zn S/Zn O(CZZ)三元异质结纳米纤维.我们对硫化过程中使用的硫化剂(硫脲)的浓度和离子层吸附沉积Cd S的次数进行调节,以优化CZZ三元异质结纳米纤维的产氢性能,经优化后的CZZ三元异质结纳米纤维在没有助催化剂的情况下产氢速率达到51.45 mmol h^–1 g^–1(420 nm处的表观量子效率达到26.88%),是相同情况下氧化锌纳米纤维的93.54倍,Zn S/Zn O二元异质结纳米纤维的2.28倍.加入贵金属Pt作助催化剂后,其产氢速率进一步提高至118.62 mmol h^–1 g^–1.为了突出一维纳米纤维对光催化产氢性能的贡献,我们采用超声辅助水热法制备得到了二维的Zn O纳米页,然后采用同样的方法和工艺对其进行硫化,得到二维的Zn S/Zn O二元异质结纳米页,最后采用同样的方法和工艺进行Cd S量子点的沉积,最终得到二维的Cd S/Zn S/Zn O三元异质结纳米页在没有助催化剂的情况下产氢速率只有9.98 mmol h^–1 g^–1,加入贵金属Pt作助催化剂后其产氢速率仅提高至27.25 mmol h^–1 g^–1.这些结果表明,与二维CZZ纳米页相比,一维CZZ纳米纤维具有更高的产氢性能.其原因可归结为:二维纳米片可以看作是由很多一维纳米纤维沿着轴线方向密集排列堆积而成的,因此与二维纳米片相比,一维纳米纤维的几何尺寸大大减小,光生电子和空穴迁移到表面的距离显著缩短,这样可以有效地抑制光生电子和空穴的复合,从而提高了光催化产氢速率.我们对一维CZZ三元异质结纳米纤维的光催化产氢机理进行了研究,发现在模拟太阳光(320–780 nm)照射下,三种半导体(Zn O,Zn S和Cd S)都能被激发产生电子和空穴.Zn S的导带位置比Zn O和Cd S的导带位置负,因此Zn S导带上的光生电子将向Zn O和Cd S的导带迁移,然后被氢离子捕获生成氢气.同时,Zn O价带上产生的光生空穴被转移到Zn S的价带上,然后与牺牲剂反应被消耗掉.对于Zn S与Cd S之间的界面,Cd S价带上的光生空穴可以跃迁到Zn S的两个杂质能级(VZn和IS)中,这样有效避免了Cd S的光腐蚀,使CZZ三元异质结呈现出很好的光催化稳定性.该工作对构建三元异质结促进光生载流子的分离和迁移具有借鉴意义. 展开更多
关键词 光催化 产氢 水分解 静电纺丝 异质结
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Distribution of IOP and its relationship with refractive error and other factors:the Anyang University Students Eye Study
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作者 dandan ma Shifei Wei +10 位作者 Yunyun Sun Shi-Ming Li Wen-Zai An Jian-Ping Hu Kai Cao Xiao-Hui Yang Cai-Xia Lin Ji-Yuan Guo He Li Jing Fu Ningli Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第4期554-559,共6页
AIM:To investigate the distribution of intraocular pressure(IOP)and its relationship with refractive error and other factors in university students from Anyang,China.METHODS:A university-based study was conducted.Subj... AIM:To investigate the distribution of intraocular pressure(IOP)and its relationship with refractive error and other factors in university students from Anyang,China.METHODS:A university-based study was conducted.Subjects were invited to complete ophthalmic examinations,including visual acuity,noncontact tonometr y(NCT),cycloplegic autorefraction,and ocular biometry.Univariable and multivariable analyses were used to evaluate the associations between IOP and other factors.Only data from right eyes were used in analysis.RESULTS:A total of 7720 subjects aged 16 to 26 years old were included,and 2834(36.4%)of the participants were male.The mean IOP of the right eye for all subjects was 15.52±3.20 mm Hg(95%CI:15.45,15.59).Using multivariate linear regression analysis,IOP was found to correlate significantly with younger age(P<0.001;standardized regression coefficientβ,-0.061;regression coefficientβ,-0.139;95%CI:-0.18,-0.09),higher myopic refractive error(P=0.044;standardizedβ,-0.060;regression coefficientβ,-0.770;95%CI:-0.15,-0.002),higher central corneal thickness(P<0.001;standardizedβ,0.450;regression coefficientβ,0.044;95%CI:0.04,0.05),and shorter axial length(AL;P<0.001;standardizedβ,-0.061;regression coefficientβ,-0.163;95%CI:-0.25,-0.07).CONCLUSION:This study described the normal distribution of IOP.In Chinese university students aged 16-26 y,higherIOP is associated with younger age,higher myopic refractive error,higher thickness of the central cornea,and shorter AL. 展开更多
关键词 intraocular pressure refractive errors EPIDEMIOLOGY university students
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Observation on Flower Bud Differentiation of Crape Myrtle in Red Soil Environment
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作者 Linxue Shang dandan ma +5 位作者 Sidan Hong Yu Zhao Guozhe Zhang Qingqing ma Qun Wang Cuihua Gu 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第12期2607-2617,共11页
Flower bud differentiation is a key component of plant blooming biology and understanding how it works is vital for flowering regulation and plant genetic breeding,increasing the number and quality of flowering.Red so... Flower bud differentiation is a key component of plant blooming biology and understanding how it works is vital for flowering regulation and plant genetic breeding,increasing the number and quality of flowering.Red soil is the most widely covered soil type in the world,and it is also the most suitable soil type for crape myrtle planting.The flower buds of crape myrtle(Lagerstroemia indica)planted in red soil were employed as experimental materials in this study,and the distinct periods of differentiation were identified using stereomicroscopy and paraffin sectioning.We optimized the steps of dehydration,transparency,embedding,sectioning and staining when employing paraffin sections.When seen under a microscope,this optimization can make the cell structure of paraffin sections obvious,the tissue structure complete,and the staining clear and natural.The flower bud differentiation process is divided into 7 periods based on anatomical observations of the external morphology and internal structure during flower bud differentiation:undifferentiated period,start of differentiation period,inflorescence differentiation period,calyx differentiation period,petal differentiation period,stamen differentiation period,and pistil differentiation period.The differentiation time is concentrated from the end of May to mid-June.Crape myrtle flower bud differentiation is a complicated process,and the specific regulatory mechanism and affecting elements need to be investigated further. 展开更多
关键词 Crape myrtle flower bud differentiation morphological structure paraffin section
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On the transformation textures influenced by deformation in electrical steels,high manganese steels and pure titanium sheets 被引量:1
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作者 Ping YANG dandan ma +1 位作者 Xinfu GU Fenge CUI 《Frontiers of Materials Science》 SCIE CSCD 2022年第1期1-16,共16页
Transformation texture is normally different to deformation and recrystallization textures,thus influencing materials properties differently.As deformation and recrystallization are often inseparable to transformation... Transformation texture is normally different to deformation and recrystallization textures,thus influencing materials properties differently.As deformation and recrystallization are often inseparable to transformation in materials which shows a variety in types such as diffusional or non-diffusional transformations,different phenomena or rules of strengthening transformation textures occur.This paper summarizes the complicated phenomena and rules by comparison of a lot of authors’published and unpublished data collected from mainly electrical steels,high manganese steels and pure titanium sheets.Three kinds of influencing deformation are identified,namely the dynamic transformation with concurrent deformation and transformation,the transformation preceded by deformation and recrystallization and the surface effect induced transformation,and the textures related with them develop in different mechanisms.It is stressed that surface effect induced transformation is particularly effective to enhance transformation texture.It is also shown that the materials properties are also improved by controlled transformation textures,in particular in electrical steels.It is hoped that these phenomena and processing techniques are beneficial to the establishment of transformation texture theory and property improvement in practice. 展开更多
关键词 electrical steel high manganese steel RECRYSTALLIZATION TRANSFORMATION TITANIUM DEFORMATION
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Wong-Zakai approximations and long term behavior of stochastic FitzHugh-Nagumo system
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作者 Ling Qin dandan ma Ji Shu 《International Journal of Biomathematics》 SCIE 2021年第3期23-52,共30页
This paper is concerned with the Wong-Zakai approximations given by a stationary pro­cess via the Wiener shift and their associated long term behavior of stochastic FitzHugh-Nagumo system driven by white noise.We... This paper is concerned with the Wong-Zakai approximations given by a stationary pro­cess via the Wiener shift and their associated long term behavior of stochastic FitzHugh-Nagumo system driven by white noise.We prove the existence and uniqueness of pullback random attractors for the approximate system under much weaker conditions than the original system.When the system is driven by additive white noise,we also prove the convergence of solutions of Wong-Zakai approximations and the upper semicontinuity of random attractors of the approximate random system as the size of approximation approaches zero. 展开更多
关键词 Wong-Zakai approximation random attractor FitzHugh-Nagumo system upper semicontinuity white noise
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Identification of prognostic indicators,diagnostic markers, and possible therapeutic targets among LIM homeobox transcription factors in breast cancer
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作者 Pingping Gao Na Sun +8 位作者 Tingting Zhao Yuanyuan Sun Jing Gu dandan ma Hao Tian Zaihui Peng Yi Zhang Fei Han Xiaowei Qi 《Cancer Innovation》 2022年第3期252-269,共18页
Background:Breast cancer(BRCA)is the most common malignant tumor among women worldwide.Despite advances in treatment,many patients still die from a lack of effective diagnostic and prognostic markers and powerful ther... Background:Breast cancer(BRCA)is the most common malignant tumor among women worldwide.Despite advances in treatment,many patients still die from a lack of effective diagnostic and prognostic markers and powerful therapeutic targets.LIM homeobox genes(LHXs)play vital roles in regulating the development of various organisms.However,there are limited reports regarding their roles in the diagnosis,prognosis,and treatment of BRCA.Methods:UALCAN,Kaplan–Meier plotter,cBioPortal,GeneMANIA,STRING,DAVID 6.8,TRRUST v2,LinkedOmics,and TIMER were utilized to analyze differential expression,prognostic value,genetic alteration,neighbor gene network,transcription factor targets,kinase targets,and immune cell infiltration of LHXs in BRCA patients.Results:LHX gene expression patterns are clear in BRCA and its different subtypes.Further analyses indicated that this altered expression is possibly affected by genetic and/or epigenetic changes.The prognostic and diagnostic values of certain LHXs are unique to different BRCA subtypes.LHXs are mainly involved in the regulation of differentiation and development,and their neighbor genes are primarily involved in cancer‐related pathways.Moreover,most LHXs are closely correlated with immune cell infiltration.Furthermore,LHXs may exert their functions by regulating a series of transcription factor and kinase targets.Conclusions:LHXs are unique diagnostic and prognostic markers and participate in cancer through different signaling pathways and/or regulatory mechanisms in BRCA.This study provides potential applications of LHXs for the diagnosis,prognosis,and treatment of BRCA and its different subtypes. 展开更多
关键词 breast cancer diagnostic and prognostic markers different subtypes LIM homeobox genes molecular mechanism
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Evaluation of ICUs and weight of quality control indicators:an exploratory study based on Chinese ICU quality data from 2015 to 2020
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作者 Longxiang Su Xudong ma +17 位作者 Sifa Gao Zhi Yin Yujie Chen Wenhu Wang Huaiwu He Wei Du Yaoda Hu dandan ma Feng Zhang Wen Zhu Xiaoyang Meng Guoqiang Sun Lian ma Huizhen Jiang Guangliang Shan Dawei Liu Xiang Zhou China-NCCQC 《Frontiers of Medicine》 SCIE CSCD 2023年第4期675-684,共10页
This study aimed to explore key quality control factors that affected the prognosis of intensive care unit(ICU)patients in Chinese mainland over six years(2015–2020).The data for this study were from 31 provincial an... This study aimed to explore key quality control factors that affected the prognosis of intensive care unit(ICU)patients in Chinese mainland over six years(2015–2020).The data for this study were from 31 provincial and municipal hospitals(3425 hospital ICUs)and included 2110685 ICU patients,for a total of 27607376 ICU hospitalization days.We found that 15 initially established quality control indicators were good predictors of patient prognosis,including percentage of ICU patients out of all inpatients(%),percentage of ICU bed occupancy of total inpatient bed occupancy(%),percentage of all ICU inpatients with an APACHE II score≥15(%),three-hour(surviving sepsis campaign)SSC bundle compliance(%),six-hour SSC bundle compliance(%),rate of microbe detection before antibiotics(%),percentage of drug deep venous thrombosis(DVT)prophylaxis(%),percentage of unplanned endotracheal extubations(%),percentage of patients reintubated within 48 hours(%),unplanned transfers to the ICU(%),48-h ICU readmission rate(%),ventilator associated pneumonia(VAP)(per 1000 ventilator days),catheter related blood stream infection(CRBSI)(per 1000 catheter days),catheter-associated urinary tract infections(CAUTI)(per 1000 catheter days),in-hospital mortality(%).When exploratory factor analysis was applied,the 15 indicators were divided into 6 core elements that varied in weight regarding quality evaluation:nosocomial infection management(21.35%),compliance with the Surviving Sepsis Campaign guidelines(17.97%),ICU resources(17.46%),airway management(15.53%),prevention of deep-vein thrombosis(14.07%),and severity of patient condition(13.61%).Based on the different weights of the core elements associated with the 15 indicators,we developed an integrated quality scoring system defined as F score=21.35%xnosocomial infection management+17.97%xcompliance with SSC guidelines+17.46%×ICU resources+15.53%×airway management+14.07%×DVT prevention+13.61%×severity of patient condition.This evidence-based quality scoring system will help in assessing the key elements of quality management and establish a foundation for further optimization of the quality control indicator system. 展开更多
关键词 critical care medicine quality control EVALUATION exploratory factor analysis(EFA)model
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Multidimensional dynamic prediction model for hospitalized patients with the omicron variant in China
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作者 Yujie Chen Yao Wang +15 位作者 Jieqing Chen Xudong ma Longxiang Su Yuna Wei Linfeng Li dandan ma Feng Zhang Wen Zhu Xiaoyang Meng Guoqiang Sun Lian ma Huizhen Jiang Chang Yin Taisheng Li Xiang Zhou China National Critical Care Quality Control Center Group 《Infectious Disease Modelling》 CSCD 2023年第4期1097-1107,共11页
Purpose:To establish dynamic prediction models by machine learning using daily multidimensional data for coronavirus disease 2019(COVID-19)patients.Methods:Hospitalized COVID-19 patients at Peking Union Medical Colleg... Purpose:To establish dynamic prediction models by machine learning using daily multidimensional data for coronavirus disease 2019(COVID-19)patients.Methods:Hospitalized COVID-19 patients at Peking Union Medical College Hospital from Nov 2nd,2022,to Jan 13th,2023,were enrolled in this study.The outcome was defined as deterioration or recovery of the patient's condition.Demographics,comorbidities,laboratory test results,vital signs,and treatments were used to train the model.To predict the following days,a separate XGBoost model was trained and validated.The Shapley additive explanations method was used to analyze feature importance.Results:A total of 995 patients were enrolled,generating 7228 and 3170 observations for each prediction model.In the deterioration prediction model,the minimum area under the receiver operating characteristic curve(AUROC)for the following 7 days was 0.786(95%CI 0.721-0.851),while the AUROC on the next day was 0.872(0.831-0.913).In the recovery prediction model,the minimum AUROC for the following 3 days was 0.675(0.583-0.767),while the AUROC on the next day was 0.823(0.770-0.876).The top 5 features for deterioration prediction on the 7th day were disease course,length of hospital stay,hypertension,and diastolic blood pressure.Those for recovery prediction on the 3rd day were age,D-dimer levels,disease course,creatinine levels and corticosteroid therapy.Conclusion:The models could accurately predict the dynamics of Omicron patients’conditions using daily multidimensional variables,revealing important features including comorbidities(e.g.,hyperlipidemia),age,disease course,vital signs,D-dimer levels,corticosteroid therapy and oxygen therapy. 展开更多
关键词 COVID-19 Omicron Prediction model Machine learning
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MicroRNA-activated hydrogel scaffold generated by 3D printing accelerates bone regeneration 被引量:2
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作者 Ting Pan Wenjing Song +5 位作者 Hongbao Xin Haiyue Yu He Wang dandan ma Xiaodong Cao Yingjun Wang 《Bioactive Materials》 SCIE 2022年第4期1-14,共14页
Bone defects remain a major threat to human health and bone tissue regeneration has become a prominent clinical demand worldwide.The combination of microRNA(miRNA)therapy with 3D printed scaffolds has always posed a c... Bone defects remain a major threat to human health and bone tissue regeneration has become a prominent clinical demand worldwide.The combination of microRNA(miRNA)therapy with 3D printed scaffolds has always posed a challenge.It can mimic physiological bone healing processes,in which a biodegradable scaffold is gradually replaced by neo-tissue,and the sustained release of miRNA plays a vital role in creating an optimal osteogenic microenvironment,thus achieving promising bone repair outcomes.However,the balance between two key factors-scaffold degradation behavior and miRNA release profile-on osteogenesis and bone formation is still poorly understood.Herein,we construct a series of miRNA-activated hydrogel scaffolds(MAHSs)generated by 3D printing with different crosslinking degree to screened the interplay between scaffold degradation and miRNA release in the osteoinduction activity both in vitro and in vivo.Although MAHSs with a lower crosslinking degree(MAHS-0 and MAHS-0.25)released a higher amount of miR-29b in a sustained release profile,they degraded too fast to provide prolonged support for cell and tissue ingrowth.On the contrary,although the slow degradation of MAHSs with a higher crosslinking degree(MAHS-1 and MAHS-2.5)led to insufficient release of miR-29b,their adaptable degradation rate endowed them with more efficient osteoinductive behavior over the long term.MAHS-1 gave the most well-matched degradation rate and miR-29b release characteristics and was identified as the preferred MAHSs for accelerated bone regeneration.This study suggests that the bio-adaptable balance between scaffold degradation behavior and bioactive factors release profile plays a critical role in bone regeneration.These findings will provide a valuable reference about designing miRNAs as well as other bioactive molecules activated scaffold for tissue regeneration. 展开更多
关键词 Bone repair microRNA therapy SCAFFOLD OSTEOGENESIS
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A cell-permeable green fluorescent probe for dsDNA 被引量:1
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作者 dandan ma Tao Liu +1 位作者 Qichao Yao Xiaojun Peng 《Science China Chemistry》 SCIE EI CAS CSCD 2018年第4期468-475,共8页
The sensitive and selective detection of nucleic acids is important for basic research and many applied fields. Herein, a novel green DEAB-TO-1 was designed and synthesized. DEAB-TO-1 shows significant fluorescence en... The sensitive and selective detection of nucleic acids is important for basic research and many applied fields. Herein, a novel green DEAB-TO-1 was designed and synthesized. DEAB-TO-1 shows significant fluorescence enhancement(800-fold) when bound to ctDNA and a distinct selectivity for dsDNA over RNA(5.9 times). Moreover, the limit of detection is 0.57 ng/ml. It is live-cell-permeant DNA intecalator,indicating a promising candidate for nucleus-specific imaging and a good counter-stain compatibility with other dyes. 展开更多
关键词 荧光灯 CTDNA 草地 渗透 房间 探查 RNA 候选人
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Role of oxygen vacancy in rare-earth-free LiCa_(3)Mg(VO_(4))_(3) phosphor: Enhancing photoluminescence by heat-treatment in oxygen flow
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作者 Yixuan Lv Yijun Zhang +7 位作者 Le Shi Jian-Wen Shi Jun Li Zhihui Li Xin Ji dandan ma Yonghong Cheng Chunming Niu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第20期123-132,共10页
As a kind of white light emitting diode(w-LED)with many advantages,rare-earth-free vanadate phosphor has attracted more and more attention.The oxygen vacancies and other surface defects in vanadate oxide have obvious ... As a kind of white light emitting diode(w-LED)with many advantages,rare-earth-free vanadate phosphor has attracted more and more attention.The oxygen vacancies and other surface defects in vanadate oxide have obvious effects on its structure and properties.In order to reveal the specific effects,we heat-treat the original LiCa_(3)Mg(VO_(4))_(3)(LCMV)in an oxygen flow with different time to decrease oxygen vacancies,and find that the lattice distortion of[VO_(4)]tetrahedron caused by oxygen vacancy is effectively reduced.Meanwhile,the crystallinity of the treated samples increases,the surface defects decreases,and the fluorescence intensity increases.The variation of photoluminescence quantum yield(PLQY)with oxygen treatment time is as follows:the enhancement effect firstly reaches the strongest(69.34%)within one hour,then begins to decline after two hours,and finally reaches the platform after three hours and remains basically unchanged.The reason for the enhancement of PLQY is the decrease of oxygen vacancy after one-hour treatment,and the reason for the decrease of PLQY after a further increased treatment time is that the absorption of oxygen and water in air caused by excessive surface defects introduced by oxygen treatment. 展开更多
关键词 PHOSPHOR Oxygen vacancy Surface defect Rare-earth-free White light emitting diode
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Se-sensitized NIR hot band absorption photosensitizer for anti-Stokes excitation deep photodynamic therapy
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作者 dandan ma Hui Bian +9 位作者 Saran Long Panwang Zhou Ruisong Tian Yingnan Wu Haoying Ge Mingle Li Jianjun Du Jiangli Fan Yukui Zhang Xiaojun Peng 《Science China Chemistry》 SCIE EI CSCD 2022年第3期563-573,共11页
Conventional anti-Stokes materials-involved deep photodynamic therapy(dPDT)requires much high-intensity irradiance due to low photosensitization efficiency.Herein,we proposed a"booster effector"approach to c... Conventional anti-Stokes materials-involved deep photodynamic therapy(dPDT)requires much high-intensity irradiance due to low photosensitization efficiency.Herein,we proposed a"booster effector"approach to construct highly efficient hot band absorption phototherapeutics for low/biosafety power anti-Stokes light-triggered d PDT.Se,as"booster effector",was introduced into hot band absorption luminophores(HBAs),which not only significantly facilitated intersystem crossing,but also simultaneously enhanced hot band excitation efficiency atν808,as a result successfully enabling excellent photogenerated singlet oxygen capability of HBAs under ultra-low power anti-Stokes excitation(10 mW cm^(-2)in vitro).As far as we know,such low laser power-initiated photosensitization activity has never been reported in the existing anti-Stokes material systems.Importantly,FUC-Se ME can self-assemble into uniform nanospheres in water,greatly boosting cellular uptake(>25-fold larger than FUC-Se),and achieve superior cancer-killing effect(808 nm,10 mW cm^(-2),5 min,the half-maximal inhibitory concentration IC50=1.36μM).After further PEGylation with folate-attached polymer,the resultant FUC-Se ME@FA can effectively enrich at the tumor(signal-to-background ratio,10).Under safety irradiation(330 mW cm^(-2)),FUC-Se ME@FA effectively inhibits deep-seated tumor progression(the tumor growth inhibition rate,84%).This work provides a successful paradigm,possibly being more clinically beneficial than conventional anti-Stokes materials. 展开更多
关键词 anti-Stokes hot band absorption photodynamic therapy deep-seated tumor low power
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Enhancing Intersystem Crossing by Intermolecular Dimer-Stacking of Cyanine as Photosensitizer for Cancer Therapy
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作者 Haiqiao Huang dandan ma +8 位作者 Qiang Liu Daipeng Huang Xueze Zhao Qichao Yao Tao Xiong Saran Long Jianjun Du Jiangli Fan Xiaojun Peng 《CCS Chemistry》 CAS 2022年第11期3627-3636,共10页
Development of new photosensitizers(PSs)with high singlet oxygen quantumyield and minimal side effects is of great interest in photodynamic therapy(PDT).Herein,a facile strategy to significantly improve photosensitiza... Development of new photosensitizers(PSs)with high singlet oxygen quantumyield and minimal side effects is of great interest in photodynamic therapy(PDT).Herein,a facile strategy to significantly improve photosensitization has been demonstrated for the first time with two pentamethine dyes connected by a varying alkyl chain resulting in a series of cyanine dimers.The photophysical properties of the dimerswere studied with steady-state optical spectroscopies,a timecorrelated single photon counting technique,and laser flash photolysis spectrometry.X-ray crystallography confirmed that the molecular packing modes of Cy-Bu-D and Cy-He-D were dominated by H-aggregation.The H-aggregation by dimerization suppresses the radiative singlet decay,which helps to stabilize the highly efficient triplet excitation state.Moreover,the dimers show more intensewavelength absorption in the nearinfrared(ɛ1.5-2.0 times more than monomer Cy-H at 650 nm),better singlet oxygen quantum yield,and a longer triplet-state lifetime than monomer Cy-H,providing excellent performance as a triplet PS.In vivo experiments demonstrated that Cy-He-D successfully suppresses tumor growth after PDT treatment.This work is beneficial to the design of novel heavy atom free PSs for PDT-based theranostic systems. 展开更多
关键词 DIMER intersystem crossing photodynamic therapy PHOTOSENSITIZERS cancer
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救助机构流浪乞讨人员归家甄别流程研究——以X市救助管理机构为例
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作者 马丹丹 范明林 《都市社会工作研究》 2017年第1期-,共22页
目前针对精神障碍的流浪乞讨人员,国家代替了其原始家庭的角色,由救助管理机构实施救助。为了保证流浪乞讨人员得到更好的服务,国家对其实行了与世隔绝的院舍管理模式。再度审视,此决策一定程度上阻碍了流浪乞讨人员的社会化,使其社会... 目前针对精神障碍的流浪乞讨人员,国家代替了其原始家庭的角色,由救助管理机构实施救助。为了保证流浪乞讨人员得到更好的服务,国家对其实行了与世隔绝的院舍管理模式。再度审视,此决策一定程度上阻碍了流浪乞讨人员的社会化,使其社会功能不断退化,对家庭的归属和爱的需求得不到满足。另外,大量的人员滞留,给国家带来沉重的经济负担。为了达到利益的双赢和资源的优化,我们是否能够完善现有的救助管理模式,提高甄别成效,体现甄别的科学性和规范性,构建出一套完整的、科学的、合理的甄别流程。本文根据在X市救助管理机构的实地研究,对此进行了深刻的反思。 展开更多
关键词 精神障碍 流浪乞讨人员 甄别
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