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Bridging gaps in corneal ulcer management:Can photoactivated chromophore for infectious keratitis-corneal collagen cross-linking delay or replace therapeutic keratoplasty?
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作者 Niki I Antonopoulou Maria S Spyropoulou +2 位作者 Stavros P Papadakos Garyfalia N Papavasileiou Andreas C Dimakis 《World Journal of Transplantation》 2026年第1期1-8,共8页
The retrospective study by Edwar et al reinforces the role of therapeutic penetrating keratoplasty(PK)as a vital intervention in severe,treatment-resistant infectious keratitis.In advanced cases—often complicated by ... The retrospective study by Edwar et al reinforces the role of therapeutic penetrating keratoplasty(PK)as a vital intervention in severe,treatment-resistant infectious keratitis.In advanced cases—often complicated by trauma,delayed presentation,and corneal perforation—PK restores globe integrity and provides limited visual recovery.However,its application is constrained by graft-related complications and donor shortages,particularly in low-resource settings.These limitations highlight the need for earlier,globe-sparing strategies to prevent progression and reduce surgical demand.Photoactivated chromophore for infectious keratitis-corneal collagen cross-linking(PACK-CXL)has emerged as a promising adjunct or alternative.With both antimicrobial and tissue-stabilizing effects,PACK-CXL may control infection and preserve corneal structure in earlier stages.A layered treatment framework that incorporates PACK-CXL as an initial intervention and reserves PK for refractory cases may help improve clinical outcomes.Further studies are needed to define their best use in practice. 展开更多
关键词 Infectious keratitis Photoactivated chromophore for infectious keratitiscorneal collagen cross-linking Corneal ulcer Therapeutic keratoplasty cross-linking therapy
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Enhanced hydrophobicity and photosensitivity of DATNBI/alginate films via ionic cross-linking for near-infrared laser ignition
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作者 Ping Ye Weimiao Wang +7 位作者 Xiaodong Li Zhiqiang Qiao Changping Guo Jinjin He Xu Zhou Rui Li Guangcheng Yang Guoqing Lv 《Defence Technology(防务技术)》 2026年第1期109-117,共9页
Based on the characteristics of laser-induced surface ignition,energetic photosensitive films show promising potential to meet the ignition requirements of various energetic materials(EMs).In this study,DATNBI/ferric ... Based on the characteristics of laser-induced surface ignition,energetic photosensitive films show promising potential to meet the ignition requirements of various energetic materials(EMs).In this study,DATNBI/ferric alginate(DI/FeA),DI/cobalt alginate(DI/CoA),and DI/nickel alginate(DI/Ni A)films are fabricated by employing sodium alginate(SA)with a three-dimensional network structure as the film matrix,via ionic cross-linking of SA with Fe^(3+),Co^(2+),and Ni^(2+)ions.The study demonstrates that the ionic cross-linking enhances the hydrophobic performance of the films,with the water contact angle increasing from 82.1° to 123.5°.Concurrently,the films'near-infrared(NIR)light absorption improved.Furthermore,transition metal ions facilitate accelerated electron transfer,thereby catalyzing the thermal decomposition of DATNBI.Under 1064 nm laser irradiation,the DI/Fe A film exhibits exceptional combustion performance,with an ignition delay time as low as 76 ms.It successfully acts as an NIR laser ignition medium to initiate the self-sustained combustion of CL-20.This study demonstrates the synergistic realization of enhanced hydrophobicity,improved photosensitivity,and promoted catalytic decomposition through microstructural design of the material,providing new insights for the design of additive-free EMs in laser ignition applications. 展开更多
关键词 DATNBI Sodium alginate Ionic cross-linking Photosensitive films Laser ignition
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In situ Generation of Carbazole-triazine Thermally Activated Delayed Fluoresscence Emitters within the Conjugated Polymer Chain
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作者 Alexander M.Mitroshin Serguei A.Miltsov +9 位作者 Ilya E.Kolesnikov Dmitriy A.Lypenko Artem V.Dmitriev Larisa S.Litvinova Vladislav M.Korshunov Ilya V.Taydakov Elena V.Ushakova Anastasia V.Rogova Felix N.Tomilin Alexander V.Yakimansky 《Chinese Journal of Polymer Science》 2026年第2期361-370,I0009,共11页
The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborat... The development of polymeric materials that exhibit blue thermally activated delayed fluorescence(TADF)is of great interest for optoelectronic applications.However,achieving TADF in polymers often requires an elaborate monomer design.The high-energy local triplet state(^(3)LE)of carbazole complicates its application despite the molecular orbital arrangement being suitable for blue emission.Here,we present an approach to polymer design that makes it possible to solve this problem.We demonstrate the in situ formation of a TADF donor-acceptor system during Suzuki polycondensation,creating an extended carbazole-based donor matrix coupled with a triazine acceptor.The resulting polymer exhibited efficient TADF with a low energy gap(ΔE_(ST))value if a phenyl N-substituent,enabling essential electron delocalization,was present in the carbazole moiety.This work establishes a versatile platform for developing carbazole-based TADF polymers,overcoming the fundamental limitations that hinder their widespread application. 展开更多
关键词 Thermally activated delayed fluorescence(TADF) POLYCARBAZOLE Suzuki polycondensation Photoluminescence
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Machine learning approaches to early detection of delayed wound healing following gastric cancer surgery
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作者 Duygu Kirkik Huseyin Murat Ozadenc Sevgi Kalkanli Tas 《World Journal of Gastrointestinal Oncology》 2026年第1期287-290,共4页
Delayed wound healing following radical gastrectomy remains an important yet underappreciated complication that prolongs hospitalization,increases costs,and undermines patient recovery.In An et al’s recent study,the ... Delayed wound healing following radical gastrectomy remains an important yet underappreciated complication that prolongs hospitalization,increases costs,and undermines patient recovery.In An et al’s recent study,the authors present a machine learning-based risk prediction approach using routinely available clinical and laboratory parameters.Among the evaluated algorithms,a decision tree model demonstrated excellent discrimination,achieving an area under the curve of 0.951 in the validation set and notably identifying all true cases of delayed wound healing at the Youden index threshold.The inclusion of variables such as drainage duration,preoperative white blood cell and neutrophil counts,alongside age and sex,highlights the pragmatic appeal of the model for early postoperative monitoring.Nevertheless,several aspects warrant critical reflection,including the reliance on a postoperative variable(drainage duration),internal validation only,and certain reporting inconsistencies.This letter underscores both the promise and the limitations of adopting interpretable machine learning models in perioperative care.We advocate for transparent reporting,external validation,and careful consideration of clinically actionable timepoints before integration into practice.Ultimately,this work represents a valuable step toward precision risk stratification in gastric cancer surgery,and sets the stage for multicenter,prospective evaluations. 展开更多
关键词 Gastric cancer Radical gastrectomy delayed wound healing Machine learning Decision tree Risk prediction
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Vibrations induced by time-delayed double blastholes in underground rocks:Experimental study and theoretical analysis
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作者 Yonggang Gou Gui Yang +2 位作者 Xianyang Qiu Kun Ji Yumin Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1108-1125,共18页
Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while... Time-delayed blasting is widely utilized in engineering to mitigate induced vibration hazards and enhance fragmentation.The underlying vibration reduction principle is the decrease of the charge weight per delay,while the potential for further vibration reduction remains debated,largely due to unclear underlying mechanisms.In light of the popularization of electronic detonators and the representativeness of double-hole configurationsfor multiple blastholes,it is essential to investigate the vibration characteristics induced by time-delayed double blastholes.Therefore,a series of doubleborehole experimental blasts was conducted in an underground roadway to clarify the variation in vibration from single-hole to dual-hole conditions.Based on the experimental data and inherent limitations,an exact full-fieldtheoretical model was further employed to systematically analyze the effects of delay time,charge length,and borehole inclination angle on vibrations induced by various doublehole configurations.The experimental data and theoretical analysis reveal that the general scaled distance effectively predicts vibrations in delayed blasting but does not reflectvibration reduction.Increasing delay time causes fluctuatingPPVs,which stabilize slightly above single-hole PPVs as delay times exceed a certain value.The delayed blasting primarily reduces near-fieldfrequencies.Longer charge lengths in double boreholes increase PPV levels and attenuation rates within a certain length,and the vibration behavior of combined long and short charge lengths is governed by the long blasthole.Larger blasthole inclination angles enhance vibration amplitude and reduce PPV attenuation rates.Optimizing inclination angles is more critical than adjusting delay times,and parallel boreholes offer the best vibration control. 展开更多
关键词 Vibration of double blastholes Experimental data Theoretical model delay time Wave superposition
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Theoretical study on the thermally activated delayed fluorescence,and efficiency roll‑off characteristics of a series of blue and blue‑green Ir(Ⅲ)complexes
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作者 QIN Zhengkun BAO Lixin +4 位作者 ZHANG Yunkai CUI Lin WANG Jinyu WANG Yuhao SONG Mingxing 《无机化学学报》 北大核心 2026年第2期365-374,共10页
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc... A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine. 展开更多
关键词 organic light‑emitting diodes Ir(Ⅲ)complex time‑dependent density functional theory thermal activation delayed fluorescence property efficiency roll‑off effect
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Mechanism of action of synaptic mitochondrial damage in delayed cognitive recovery
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作者 Huihui Miao Qiang Liu +7 位作者 Yan-Ping Liu Bin-Bin Yan Xin-Hao Jiao Hai-Bi Wang Cheng-Hua Zhou Tianzuo Li Zhongcong Xie Yuqing Wu 《Neural Regeneration Research》 2026年第6期2457-2466,共10页
Delayed neurocognitive recovery following anesthesia and surgery is a common complication in older adult patients.Synapses are fundamental to cognitive function.The activity of synapses heavily depends on the energy s... Delayed neurocognitive recovery following anesthesia and surgery is a common complication in older adult patients.Synapses are fundamental to cognitive function.The activity of synapses heavily depends on the energy supplied by synaptic mitochondria,which are significantly influenced by oxidative stress.Sirtuin 3 is a histone deacetylase located in the mitochondrial matrix that plays a pivotal role in regulating mitochondrial function.However,it remains unclear whether and how sirtuin 3 is involved in the development of delayed cognitive recovery.Therefore,in this study,we investigated the potential role of sirtuin 3 in synapses during delayed neurocognitive recovery.Our results showed that anesthesia and surgery induced cognitive impairment in mice and reduced sirtuin 3 protein expression.Overexpression of sirtuin 3 inhibited opening of the mitochondrial permeability transition pore by reducing acetylation of K166 on cyclophilin D and also rescued cognitive impairment.Aged mice carrying the cyclophilin D-K166R mutation exhibited significantly reduced cognitive impairment.Similarly,administering the mitochondrial permeability transition pore blocker,cyclosporine A,effectively alleviated the decline in synaptic mitochondrial function and cognitive impairment caused by anesthesia and surgery in aged mice.These results indicate that the sirtuin 3/cyclophilin D-K166/mPTP signaling pathway in hippocampal synaptic mitochondria is involved in delayed neurocognitive recovery of aged mice,suggesting this pathway could serve as a potential target for treatment. 展开更多
关键词 acetylase aged mice cyclophilin D delayed neurocognitive recovery hippocampus long-term potentiation mitochondrial permeability transition pore sirtuin 3 synaptic mitochondria SYNAPTOSOME
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Simultaneous versus sequential corneal cross-linking and intracorneal ring segments implantation for keratoconus: two-year study
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作者 Ismail Omar Rasha Safwat Elhiny 《International Journal of Ophthalmology(English edition)》 2025年第5期840-845,共6页
AIM:To compare simultaneous corneal collagen cross-linking(CXL)with intracorneal ring segment(ICRS)implantation versus successive ICRS followed by CXL and detect the impact of the timing of CXL after ICRS implantation... AIM:To compare simultaneous corneal collagen cross-linking(CXL)with intracorneal ring segment(ICRS)implantation versus successive ICRS followed by CXL and detect the impact of the timing of CXL after ICRS implantation in the successive method.METHODS:This is a retrospective study of the records of three groups of patients.Group 1 of 28 patients were operated on with simultaneous ICRS implantation and CXL,group 2 of 32 patients had ICRS implantation followed by CXL after 1mo,and group 3 of 38 patients had ICRS implantation followed by CXL after 3mo.The three groups had follow-up visits after 6,12,and 24mo.RESULTS:The preoperative data,age,and gender differences among 3 groups revealed no significant differences.The postoperative spherical equivalent and best-corrected visual acuity were improved significantly in all groups compared to the baseline,which were more evident in groups 1 and 2.The differences between preoperative and postoperative mean values of mean of K readings(Km)and maximum K reading(Kmax)at 6mo were 4.66 and 4.1 D in group 1,4.43 and 4.64 D in group 2,but 3.2 and 3.4 D in group 3,respectively.The spherical aberrations and the vertical coma showed significant postoperative changes in all groups,and trefoil showed nonsignificant changes.CONCLUSION:Simultaneous and sequential ICRS implantation and CXL at 1mo has similar Km and Kmax better postoperative changes than when both surgeries were done at three-month intervals. 展开更多
关键词 KERATOCONUS cross-linking intracorneal ring ABERRATIONS
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Relative controllability of Langevin delayed fractional system with multiple delays in control
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作者 Mustafa Aydin Nazim I.Mahmudov 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第4期937-954,共18页
A Langevin delayed fractional system with multiple delays in control,is a delayed fractional system that includes delay parameters in both state and control,is first introduced.This paper is devoted to investigating t... A Langevin delayed fractional system with multiple delays in control,is a delayed fractional system that includes delay parameters in both state and control,is first introduced.This paper is devoted to investigating the relative controllability of the Langevin delayed fractional system with multiple delays in control.For linear systems to be relatively controllable,necessary and sufficient circumstances are identified by introducing and employing the Gramian matrix.The sufficient conditions for the relative controllability of semilinear systems are ofered based on Schauder's fixed point theorem.As an unusual approach,the controllability results of the delayed system are built for the first time on the exact solution produced by the MittagLeffler type function although controllability ones in the literature are built on the Volterra integral equations or the mild solutions produced by resolvent families. 展开更多
关键词 Langevin delayed fractional system delayed analogue of Mittag-Leffler type function relative controllability control delay integral-fractional differential equation
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Corneal surface changes after stromal lenticule addition keratoplasty combined with cross-linking for severe keratoconus
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作者 Xi-Yu Sun Di Shen +5 位作者 Hao-Xi Chen Wen-Jia Cao Kun Zhou Ya-Ni Wang Rui Wang Wei Wei 《International Journal of Ophthalmology(English edition)》 2025年第6期1003-1010,共8页
AIM:To investigate the response of the anterior and posterior corneal surface in femtosecond laser-assisted convex stromal lenticule addition keratoplasty(SLAK)combined with cross-linking(CXL)for treating keratoconus ... AIM:To investigate the response of the anterior and posterior corneal surface in femtosecond laser-assisted convex stromal lenticule addition keratoplasty(SLAK)combined with cross-linking(CXL)for treating keratoconus at the first 3mo of follow-up.METHODS:In this prospective observational study,20 eyes of 20 keratoconus patients who underwent SLAK combined with CXL were included.The morphological indices in keratometry and elevation data were recorded from the Sirius at baseline and 1 and 3mo postoperatively.The mean values of maximum keratometry(K_(max)),flat keratometry(K_(1)),and steep keratometry(K_(2))at the central,3-mm,5-mm,and 7-mm areas were measured from the curvature map.The changes in anterior and posterior corneal elevation under the best-fit sphere(BFS)radius at seven points horizontally of the center,3-mm,5-mm,and 7-mm area from the center at both nasal(N)and temporal(T)side were measured from elevation map.RESULTS:For the front corneal curvature,K_(1),and K_(2) at 3-mm,5-mm,and 7-mm of the anterior corneal surface increased significantly 1mo postoperatively(all P<0.05)and remained unchanged until 3mo(P>0.05).For the back corneal curvature,K_(1) and K_(2) along the 3-mm back meridian significantly decreased after month 1(P=0.002,0.077,respectively).Posterior K_(2)-readings along the 5-mm and 7-mm did not change after surgery(P>0.05).Anterior BFS decreased 1mo(P<0.001)postoperatively but remained unchanged until 3mo after SLAK(P>0.05).There was no change in posterior BFS before and after the surgery(P>0.05).Anterior elevation at N5,N3,central,and T5 points and posterior elevation at central and T7 points shifted backward 1mo postoperatively(all P<0.05)and remained stable until 3mo(P>0.05).CONCLUSION:The myopic SLAK combined with CXL is an economical alternative for stabilizing the corneal surface in severe keraoconus.“Pseudoprogression”occurs in the early phase postoperatively,but it is not an indicator of keratoconus progression. 展开更多
关键词 small incision lenticule extraction lenticule ADDITION cross-linking KERATOCONUS
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Advancements in hyaluronic acid cross-linking modalities and implant strategies for mitigating skin aging
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作者 Zi-Bo Chen Yi-Wen Luo +8 位作者 Yi Zhen Guo Chen Kai-Yu Cao Hao Chen Liu Wang Gang Li Jie Wang Jie Dang Shan-Shan Xu 《Biomedical Engineering Communications》 2025年第1期12-25,共14页
Aging is a persistent topic of interest,with skin aging as its most visible manifestation,characterized by a reduction in intact collagen and elastic fibers in the dermis.Hyaluronic acid,a vital component of the extra... Aging is a persistent topic of interest,with skin aging as its most visible manifestation,characterized by a reduction in intact collagen and elastic fibers in the dermis.Hyaluronic acid,a vital component of the extracellular matrix present in the skin,has become a mainstream method for skin rejuvenation through injections.However,the rapid degradation of pure hyaluronic acid,combined with insufficient maintenance duration and often limited therapeutic effects,presents significant challenges for injectable treatments.Additionally,low patient compliance due to discomfort from needles penetrating the dermal layer further complicates its use.In this review,we summarize and compare existing interventions for skin aging,focusing on strategies to prolong the degradation cycle of hyaluronic acid,including variations in cross-linking modalities and injection techniques.We conclude that the injection of cross-linked modified hyaluronic acid via microneedles represents a promising approach to extend the degradation cycle,offering valuable insights for current therapeutic strategies. 展开更多
关键词 skin aging hyaluronic acid cross-linking modalities implant strategies
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Effect of retinoic acid on delayed encephalopathy after acute carbon monoxide poisoning:Role of the lncRNA SNHG15/LINGO-1/BDNF/TrkB axis
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作者 HUANG Fangling WANG Su’e +2 位作者 PENG Zhengrong HUANG Xu BAI Sufen 《中南大学学报(医学版)》 北大核心 2025年第6期955-969,共15页
Objective:The neurotoxicity of carbon monoxide(CO)to the central nervous system is a key pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning(DEACMP).Our previous study found that retinoic acid... Objective:The neurotoxicity of carbon monoxide(CO)to the central nervous system is a key pathogenesis of delayed encephalopathy after acute carbon monoxide poisoning(DEACMP).Our previous study found that retinoic acid(RA)can suppress the neurotoxic effects of CO.This study further explores,in vivo and in vitro,the molecular mechanisms by which RA alleviates CO-induced central nervous system damage.Methods:A cytotoxic model was established using the mouse hippocampal neuronal cell line HT22 and primary oligodendrocytes exposed to CO,and a DEACMP animal model was established in adult Kunming mice.Cell viability and apoptosis of hippocampal neurons and oligodendrocytes were assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay and Annexin V/propidium iodide(PI)double staining.The transcriptional and protein expression of each gene was detected using real time fluorescence quantitative PCR(RT-qPCR)and Western blotting.Long noncoding RNA(lncRNA)SNHG15 and LINGO-1 were knocked down or overexpressed to observe changes in neurons and oligodendrocytes.In DEACMP mice,SNHG15 or LINGO-1 were knocked down to assess changes in central nervous tissue and downstream protein expression.Results:RA at 10 and 20μmol/L significantly reversed CO-induced apoptosis of hippocampal neurons and oligodendrocytes,downregulation of SNHG15 and LINGO-1,and upregulation of brain-derived neurotrophic factor(BDNF)and tyrosine kinase receptor B(TrkB)(all P<0.05).Overexpression of SNHG15 or LINGO-1 weakened the protective effect of RA against CO-induced cytotoxicity(all P<0.05).Knockdown of SNHG15 or LINGO-1 alleviated CO-induced apoptosis of hippocampal neurons and oligodendrocytes and upregulated BDNF and TrkB expression levels(all P<0.05).Experiments in DEACMP model mice showed that knockdown of SNHG15 or LINGO-1 mitigated central nervous system injury in DEACMP(all P<0.05).Conclusion:RA alleviates CO-induced apoptosis of hippocampal neurons and oligodendrocytes,thereby reducing central nervous system injury and exerting neuroprotective effects.LncRNA SNHG15 and LINGO-1 are key molecules mediating RA induced inhibition of neuronal apoptosis and are associated with the BDNF/TrkB pathway.These findings provide a theoretical framework for optimizing the clinical treatment of DEACMP and lay an experimental foundation for elucidating its molecular mechanisms. 展开更多
关键词 delayed encephalopathy after acute carbon monoxide poisoning apoptosis retinoic acid NEUROPROTECTION LINGO-1 lncRNA SNHG15
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Physicochemical dual cross-linking polymer stabilizing the Si-C-Cu interfaces for long-life silicon anode
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作者 Wenhui Fu Yuxuan Tian +5 位作者 Chao Sui Xiaorui Wang Zhi Wang Qiushi Chen Junhao Liu Xuzhong Gong 《Journal of Energy Chemistry》 2025年第6期732-741,I0015,共11页
Polymer binders possess significant potential in alleviating the volume expansion issues of silicon-based anodes,yet remain challenging due to insufficient interfacial interactions with individual components(Si,C,and ... Polymer binders possess significant potential in alleviating the volume expansion issues of silicon-based anodes,yet remain challenging due to insufficient interfacial interactions with individual components(Si,C,and Cu)of the anode.Herein,we report the synthesis of a stable three-dimensional network structure of the PAA-PEA(polyacrylic acid-polyether amines)polymer binder through intermolecular physicochemical dual cross-linking.By incorporating polar functional groups,the binder molecules not only form strong C-O-Si,N-Si,O=C-O-C,and O=C-O-Cu covalent bonds but also enhance non-covalent interactions with Si,C,and Cu,thereby improving adhesion between the binder and each interface of the anode.Furthermore,weak hydrogen bonds,acting as"sacrificial bonds",dissipate energy and disperse accumulated stress,improving the material flexibility.Due to the high mechanical stability of the framework,which combines both rigidity and flexibility and the coupling effect at the three interfaces,the movement and separation of electrode components are effectively restrained,significantly enhancing the cycling stability of silicon-graphite anodes.The PAA-PEA 2000 electrode exhibits a capacity retention of 78% after 500 cycles at a current density of 0.2 A g^(-1).This work provides insights into the mechanism of binders and guides the design of polymer binders for high-performance Si-based electrodes. 展开更多
关键词 BINDER Silicon-graphite anode Interface Dual cross-linking Lithium-ion batteries
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Effect of Cross-Linking Density of Powdered Rubber on Gas Barrier Property and CO_(2) Permselectivity of NR/BR Composites
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作者 Peng-Cheng Xia Hua-Feng Shao Ai-Hua He 《Chinese Journal of Polymer Science》 2025年第1期199-210,I0013,共13页
In this study,a novel cost-effective methodology was developed to enhance the gas barrier properties and permselectivity of unfilled natural rubber(NR)/polybutadiene rubber(BR)composites through the construction of a ... In this study,a novel cost-effective methodology was developed to enhance the gas barrier properties and permselectivity of unfilled natural rubber(NR)/polybutadiene rubber(BR)composites through the construction of a heterogeneous structure using pre-vulcanized powder rubber to replace traditional fillers.The matrix material is composed of a blend of NR and BR,which is widely used in tire manufacturing.By incorporating pre-vulcanized trans-1,4-poly(isoprene-co-butadiene)(TBIR)rubber powder(pVTPR)with different cross-linking densities and contents,significant improvements in the gas barrier properties and CO_(2)permselectivity of the NR/BR/pVTPR composites were observed.The results indicated that compared to NR/BR/TBIR composites prepared through direct blending of NR,BR,and TBIR,the NR/BR/pVTPR composites exhibited markedly superior gas barrier properties.Increasing the cross-linking density of pVTPR resulted in progressive enhancement of the gas barrier properties of the NR/BR/pVTPR composite.For example,the addition of 20 phr pVTPR with a cross-linking density of 346 mol/m^(3)resulted in a 79%improvement in the oxygen barrier property of NR/BR/pVTPR compared to NR/BR,achieving a value of 5.47×10^(-14)cm^(3)·cm·cm^(-2)·s^(-1)·Pa^(-1).Similarly,the nitrogen barrier property improved by 76%compared to NR/BR,reaching 2.4×10^(-14)cm^(3)·cm·cm^(-2)·s^(-1)·Pa^(-1),which is 28%higher than the conventional inner liner material brominated butyl rubber(BIIR,PN2=3.32×10^(-14)cm^(3)·cm·cm^(-2)·s^(-1)·Pa^(-1)).Owing to its low cost,exceptional gas barrier properties,superior adhesion to various tire components,and co-vulcanization capabilities,the NR/BR/pVTPR composite has emerged as a promising alternative to butyl rubber in the inner liner of tires.Furthermore,by fine-tuning the cross-linking density of pVTPR,the high-gas-barrier NR/BR/pVTPR composites also demonstrated remarkable CO_(2)permselectivity,with a CO_(2)/N2 selectivity of 61.4 and a CO_(2)/O_(2)selectivity of 26.12.This innovation provides a novel strategy for CO_(2)capture and separation,with potential applications in future environmental and industrial processes.The multifunctional NR/BR/pVTPR composite,with its superior gas barrier properties and CO_(2)permselectivity,is expected to contribute to the development of safer,greener,and more cost-effective transportation solutions. 展开更多
关键词 Gas barrier CO_(2)separation cross-linking density Powdered rubber Inner liner
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Symbol Labeling for LDPC Coded Delayed BICM in a Two-Way Relay Channel
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作者 Zhang Zhe Zhou Liang +1 位作者 Du Junyi Zhou Zhiheng 《China Communications》 2025年第10期170-178,共9页
This paper is concerned with design-ing symbol labeling for a low-density parity-check(LDPC)-coded delayed bit-interleaved coded modu-lation(DBICM)scheme in a two-way relay channel(TWRC).We first present some properti... This paper is concerned with design-ing symbol labeling for a low-density parity-check(LDPC)-coded delayed bit-interleaved coded modu-lation(DBICM)scheme in a two-way relay channel(TWRC).We first present some properties of symbol labeling within a phase shift keying(PSK)modula-tion.These properties reduce the candidate labeling search space.Based on this search space,we take DBICM capacity as the cost function and propose a general method for optimizing symbol labeling by em-ploying the differential evolution algorithm.Numeri-cal results show that our labeling obtains a signal-to-noise ratio(SNR)gain up to 0.45 dB with respect to Gray labeling. 展开更多
关键词 delayed BICM LDPC symbol labeling two-way relay channel
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Development and Internal Validation of a Predictive Model for Delayed Discharge Following Ambulatory Retrograde Intrarenal Surgery
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作者 Peng Yang 《Science International Innovative Medicine》 2025年第1期76-85,共10页
Through systematic analysis of risk factors associated with postoperative delayed discharge following retrograde intrarenal surgery(RIRS)with flexible ureteroscopic holmium laser lithotripsy under ambulatory surgery p... Through systematic analysis of risk factors associated with postoperative delayed discharge following retrograde intrarenal surgery(RIRS)with flexible ureteroscopic holmium laser lithotripsy under ambulatory surgery protocols,this study aims to develop and validate a risk prediction model for discharge delay.The ultimate objectives include establishing evidence-based clinical guidelines for urolithiasis management,enabling proactive intervention strategies,and optimizing physician-patient communication efficiency.METHODS:This retrospective cohort study analyzed clinical data from 253 patients undergoing ambulatory retrograde intrarenal surgery(RIRS)with flexible ureteroscopic holmium laser lithotripsy at the Day Surgery Unit and Urology Department of Hunan Provincial People's Hospital between January 2023 and December 2024.To identify predictors of discharge delay,Lasso-regularized logistic regression analysis was implemented for variable selection,followed by multivariable logistic regression modeling via R statistical software(version 4.3.1).A clinical prediction nomogram was developed to visualize risk stratification,with model performance evaluated through receiver operating characteristic(ROC)curve analysis,calibration plots,and decision curve analysis(DCA).Internal validation was conducted using 1,000-cycle bootstrap resampling to ensure model generalizability. 展开更多
关键词 Retrograde Intrarenal Surgery AMBULATORY delayed discharge Predictive Model
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Nomogram for prediction of six-month mortality following endovascular treatment of delayed post-pancreatectomy hemorrhage
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作者 Ding-Wei Deng Ai-Xin Leng +1 位作者 Qiang He Chuan-Guo Zhou 《World Journal of Gastrointestinal Surgery》 2025年第12期234-249,共16页
BACKGROUND Delayed post-pancreatectomy hemorrhage(PPH)is life-threatening,and endovascular interventions show promise.This retrospective study aimed to evaluate endovascular treatment outcomes for delayed PPH and iden... BACKGROUND Delayed post-pancreatectomy hemorrhage(PPH)is life-threatening,and endovascular interventions show promise.This retrospective study aimed to evaluate endovascular treatment outcomes for delayed PPH and identify mortality risk factors.AIM To conduct a single-center retrospective study of 88 patients with delayed PPH to systematically evaluate the clinical efficacy of endovascular treatment,identify independent risk factors for six-month mortality,and propose and validate a predictive model for individualized management of high-risk patients.METHODS This retrospective analysis included 88 patients with delayed PPH treated by endovascular intervention.Patients were stratified into survival(n=64)and mortality(n=24)groups.Clinical and procedural variables were assessed using univariate and multivariate logistic regression.Significant predictors were incorporated into a prognostic nomogram.Model performance was assessed through discrimination(area under the receiver operating characteristic curve),calibration,and decision curve analysis.RESULTS Technical and clinical success rates were 92.0%and 60.2%,respectively.The overall six-month mortality rate was 27.3%(24/88).Independent predictors of mortality included advanced age,prolonged operative time,shorter hospital stay,intra-abdominal infection,coagulation dysfunction,common hepatic artery bleeding,and failure to achieve clinical success.The nomogram demonstrated excellent discrimination(area under the receiver operating characteristic curve=0.943),with good calibration and favorable net benefit on decision curve analysis.CONCLUSION We proposed and validated a predictive nomogram for six-month mortality following endovascular treatment for delayed PPH.The model facilitates individualized risk stratification and may guide clinical decision-making.Early identification of high-risk patients-particularly older individuals or those with infection or coagulopathy-and prompt,personalized intervention may improve outcomes in this high-risk population. 展开更多
关键词 delayed post-pancreatectomy hemorrhage Endovascular intervention Pancreaticoduodenectomy Mortality Clinical outcome NOMOGRAM
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Fabrication of carbon-supported Al_(2)O_(3) nanoparticles via spontaneous cross-linking to enhance selective hydrogenation of furfural
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作者 Weiwei Yu Xinbao Zhang +6 位作者 Hongyu Chen Yanan Wang Shaoguo Li Fucun Chen Zhenni Liu Xiujie Li Xiangxue Zhu 《Journal of Energy Chemistry》 2025年第1期612-620,共9页
Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,... Selective hydrogenation of furfural to furfuryl alcohol is a great challenge in the hydrogenation field due to thermodynamic preference for hydrogenation of C=C over C=O.Herein,a novel Al_(2)O_(3)/C-u hybrid catalyst,composed of N-modified dendritic carbon networks supporting Al_(2)O_(3)nanoparticles,was successfully prepared via carbonizing the freeze-dried gel from spontaneous cross-linking of alginate,Al3+and urea.The obtained carbon-supported Al_(2)O_(3)hybrid catalyst has a high ratio (31%) of Al species in pentahedral-coordinated state.The introduction of urea enhances the surface N content,the ratio of pyrrolic N,and specific surface area of catalyst,leading to improved adsorption capacity of C=O and the accessibility of active sites.In the furfural hydrogenation reaction with isopropyl alcohol as hydrogen donor,Al_(2)O_(3)/C-u catalyst achieved a 90%conversion of furfural with 98.0% selectivity to furfuryl alcohol,outperforming that of commercial γ-Al_(2)O_(3).Moreover,Al_(2)O_(3)/C-u demonstrates excellent catalytic stability in the recycling tests attributed to the synergistic effect of abundant weak Lewis acid sites and the anchoring effect of the carbon network on Al_(2)O_(3)nanoparticles.This work provides an innovative and facile strategy for fabrication of carbon-supported Al_(2)O_(3)hybrid catalysts with rich AlVspecies,serving as a high selective hydrogenation catalyst through MPV reaction route. 展开更多
关键词 Selective hydrogenation FURFURAL Furfuryl alcohol cross-linking Carbon supported Al_(2)O_(3) MPV route
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Optimizing Contrast-Enhanced Magnetic Resonance Neurography of the Brachial Plexus With Delayed Scanning
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作者 Jun Xu Xiaoli Hu +7 位作者 Xiaoyun Su Shen Gui Ziqiao Lei Xiaoming Liu Xiangzhi Zhou Lixia Wang Wenjun Wu Xiangchuang Kong 《iRADIOLOGY》 2025年第2期168-175,共8页
Background:Contrast-enhanced magnetic resonance neurography(ceMRN)can enhance brachial plexus visualization and quality of imaging.However,the interval between contrast injection and scanning that provides the highest... Background:Contrast-enhanced magnetic resonance neurography(ceMRN)can enhance brachial plexus visualization and quality of imaging.However,the interval between contrast injection and scanning that provides the highest-quality images is not known.Methods:Fifteen patients underwent brachial plexus imaging using the 3D T2-NerveView sequence with a scanning duration of 5 min.A consecutive six-phase scan was initiated immediately at the start of contrast agent injection.Subsequently,all patients'images were classified into six groups according to the phases:group A(phase 1,delay 0 min),group B(phase 2,delay 5 min),group C(phase 3,delay 10 min),group D(phase 4,delay 15 min),group E(phase 5,delay 20 min),and group F(phase 6,delay 25 min).The image quality in each group was assessed based on nerve signal(signalnerve),muscle signal(signalmuscle),lymph node signal(signallymph node),background noise(BN),signal-to-noise ratio(SNR),contrast-to-noise ratio(CNR),and subjective score.Results:Signalnerve,signalmuscle,BN,and SNR did not significantly differ among the six groups(p>0.05).However,significant differences(p<0.05)were observed in signallymph node(F=16.067),CNR(F=9.495),and subjective score(χ^(2)=23.586).As the scanning delay increased,signallymph node intensity gradually increased whereas the CNR gradually decreased.The subjective score was significantly higher in groups B(4.830.24),C(4.900.21),D(4.870.30),E(4.830.31),and F(4.830.31)than in group A(4.470.30).Conclusion:We recommend performing brachial plexus ceMRN 5 min after contrast injection.With this delay,the brachial plexus can be visualized optimally with minimal interference from background signals. 展开更多
关键词 brachial plexus compressed sensing delayed scanning image quality magnetic resonance neurography
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An intelligent micro-nano capsule green hydrogel decorated with carbon quantum dots with delayed crosslinking characteristics for enhanced oil recovery in harsh reservoir
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作者 Chuan-Hong Kang Ji-Xiang Guo +2 位作者 Zheng-Hao Zhang Wyclif Kiyingi Peng-Cheng Xue 《Petroleum Science》 2025年第11期4809-4822,共14页
Hydrogels are widely used in reservoir flow control to enhanced oil recovery.However,challenges such as environmental contamination from conventional crosslinkers,poor solubility of crosslinking agents,and short gelat... Hydrogels are widely used in reservoir flow control to enhanced oil recovery.However,challenges such as environmental contamination from conventional crosslinkers,poor solubility of crosslinking agents,and short gelation times under high-temperature conditions(e.g.,150℃)have hindered their practical application.Herein,we present the synthesis of amine-functionalized carbon quantum dots(NH_(2)-CQDs),which act as both a nano-crosslinker and a nano-reinforcing agent within hydrogel systems.The NH_(2)-CQDs-incorporated hydrogel can remain stability for 300 days under the conditions of a mineralization degree of 2.11×10^(4)mg/mL and 170℃,and has high tensile strength(371 kPa),good toughness(49.6 kJ/m^(3)),excellent viscoelasticity(G'=960 Pa,G"=460 Pa)and shear resistance.In addition,NH_(2)-CQDs adds many hydroxyl groups to the hydrogel,which can be attached to the surface of various substances.At the same time,micro-nano capsules containing NH_(2)-CQDs were formed by self-assembly of hydrophobic SiO_(2)on water droplets,the NH_(2)-CQDs solution is encapsulated in a capsule,and when stimulated by external conditions(temperature,pH,surfactant),the capsule releases the NH_(2)-CQDs solution,this method greatly delays the crosslinking time between polymer and crosslinker at high temperature.Under the condition of 170℃and pH=7,the gelation time of 10%hydrophobic SiO_(2)coated hydrogel is 44 times that of uncoated hydrogel,which can be effectively used for deep formation flow control,and CQD give hydrogels fluorescence properties that can be used for underground signal tracking. 展开更多
关键词 Carbon quantum dots Intelligent response Green hydrogel delayed crosslinking Enhanced oil recovery
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