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Pharmacological and light-driven pupillary accommodation in guinea pigs:comparative effects of muscarinic modulators and illumination across developmental stages
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作者 Hao Wu Na Lu +5 位作者 Zhong-Bao Qiao Chi Cheng Wen-Ting Luo Ting Wan Tong Qiao Yue Di 《International Journal of Ophthalmology(English edition)》 2026年第2期211-218,共8页
AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups ... AIM:To investigate the effects of different light intensities and various mydriatic and miotic drugs on pupil accommodation in guinea pigs.METHODS:Forty-two-week-old guinea pigs were randomly divided into four groups to assess pupillary responses under varying light intensities(100,250,500 lx)and pharmacological interventions(1%atropine,1%cyclopentolate,1%tropicamide,or 2%pilocarpine).Baseline pupil size and eccentricity were recorded using a non-contact Python-based imaging system integrating edge detection and pixel-to-distance conversion.Direct illumination effects were measured at sequential time points,followed by drug administration and longitudinal tracking of pupillary changes.The protocol was repeated at 12wk of age for developmental comparisons.Postexperiment,enucleated eyes were analyzed to evaluate in vitro vs in vivo differences.RESULTS:Significant age-dependent differences in pupil dynamics were observed.Both 2-and 12-week-old guinea pigs exhibited marked pupil constriction under direct illumination(P<0.001),with decreased eccentricity post-constriction(P<0.001).Indirect illumination caused inconsistent pupil size changes(2-week:P=0.68;12-week:P=0.49).Pharmacologically,atropine,cyclopentolate,and tropicamide induced pupil dilation(P<0.001),whereas pilocarpine caused constriction(P<0.001).All drug groups showed reduced eccentricity(P<0.001).In vivo/in vitro comparisons revealed significant structural differences.CONCLUSION:This study investigates pupillary responses in developing guinea pigs,revealing a direct pupillary light reflex(PLR)with light intensity-dependent responses,while indirect PLR was undetectable.The differential effects of muscarinic modulators on pupillary responses underscore the critical role of cholinergic signaling in ocular accommodation,with age-related variations in sensitivity.Additionally,a novel non-contact measurement methodology achieved a precision of 0.01 mm for pupillary quantification,enhancing accuracy in ocular studies. 展开更多
关键词 PUPIL guinea pig muscarinic receptor modulator light reflex
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Lysophosphatidic acid signaling:Transmembrane modulators in the central nervous system
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作者 Alexandra Polyzou Alexandros Κ.Tsiouris +2 位作者 Charalampos Labrakakis Britta J.Eickholt George Leondaritis 《Neural Regeneration Research》 2026年第3期1104-1105,共2页
Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,includi... Lysophosphatidic acid(LPA)is a pleiotropic lipid agonist essential for functions of the central nervous system(CNS).It is abundant in the developing and adult brain while its concentration in biological fluids,including cerebrospinal fluid,varies significantly(Figure 1Α;Yung et al.,2014).LPA actually corresponds to a variety of lipid species that include different stereoisomers with either saturated or unsaturated fatty acids bearing likely differentiated biological activities(Figure 1Α;Yung et al.,2014;Hernández-Araiza et al.,2018). 展开更多
关键词 transmembrane modulators cerebrospinal fluidvaries variety lipid species lysophosphatidic acid biological fluidsincluding lysophosphatidic acid lpa saturated unsaturated fatty acids pleiotropic lipid agonist
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Discoidin domain receptor 2 is an important modulator of BMP signaling during heterotopic bone formation 被引量:1
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作者 Fashuai Wu Chunxi Ge +4 位作者 Haichun Pan Yuanyuan Han Yuji Mishina Vesa Kaartinen Renny T.Franceschi 《Bone Research》 2025年第1期121-138,共18页
Bone morphogenetic proteins are essential for bone regeneration/fracture healing but can also induce heterotopic ossification(HO).Understanding accessory factors modulating BMP signaling would provide both a means of ... Bone morphogenetic proteins are essential for bone regeneration/fracture healing but can also induce heterotopic ossification(HO).Understanding accessory factors modulating BMP signaling would provide both a means of enhancing BMP-dependent regeneration while preventing HO.This study focuses on the ability of the collagen receptor,discoidin domain receptor 2(DDR2),to regulate BMP activity.As will be shown,induction of bone formation by subcutaneous BMP2 implants is severely compromised in Ddr2-deficient mice.In addition,Ddr2 deficiency attenuates HO in mice expressing the ACVR1 mutation associated with human fibrodysplasia ossificans progressiva.In cells migrating into BMP2 implants,DDR2 is co-expressed with GLI1,a skeletal stem cell marker,and DDR2/GLI1-positive cells participate in BMP2-induced bone formation where they contribute to chondrogenic and osteogenic lineages.Consistent with this distribution,conditional knockout of Ddr2 in Gli1-expressing cells inhibited bone formation to the same extent seen in globally Ddr2-deficient animals.This response was explained by selective inhibition of Gli1+cell proliferation without changes in apoptosis.The basis for this DDR2 requirement was explored further using bone marrow stromal cells.Although Ddr2 deficiency inhibited BMP2-dependent chondrocyte and osteoblast differentiation and in vivo,bone formation,early BMP responses including SMAD phosphorylation remained largely intact.Instead,Ddr2 deficiency reduced the nuclear/cytoplasmic ratio of the Hippo pathway intermediates,YAP and TAZ.This suggests that DDR2 regulates Hippo pathway-mediated responses to the collagen matrix,which subsequently affect BMP responsiveness.In summary,DDR2 is an important modulator of BMP signaling and a potential therapeutic target both for enhancing regeneration and treating HO. 展开更多
关键词 inhibited HEALING modulator
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Neuropeptide cholecystokinin:a key neuromodulator for hippocampal functions
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作者 Fengwen Huang Stephen Temitayo Bello 《Neural Regeneration Research》 SCIE CAS 2025年第7期1991-1992,共2页
Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodu... Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodulators shape its functions(Teixeira et al.,2018;Zhang et al.,2024).However,the landscape of neuromodulations in the hippocampal system remains poorly understood because most studies focus on classical monoamine neuromodulators,such as acetylcholine,serotonin,dopamine,and noradrenaline.The neuropeptides,comprising the most abundant neuromodulators in the central nervous system,play a pivotal role in neural information processing in the hippocampal system.Cholecystokinin(CCK),one of the most abundant neuropeptides,has been implicated in regulating various physiological and neurobiological statuses(Chen et al.,2019).CCK-A receptor(CCK-AR)and CCK-B receptors(CCK-BR)are two key receptors mediating the biological functions of CCK,both of which belong to class-A sevenfold transmembrane G protein-coupled receptors(Nishimura et al.,2015).CCK-AR preferentially reacts to sulfated CCK,whereas CCK-BR binds both CCK and gastrin with similar affinities(Ding et al.,2022).The expression patterns of CCK-AR and CCK-BR are distinct,implying that CCK has various functions in target regions.For instance,CCK-AR is widely expressed in the GI and brain subregions and is hence implicated in the control of digestive function and satiety regulation.Conversely,CCK-BR is abundantly and widely distributed in the central nervous system,which majorly regulates anxiety,learning,and memory(Ding et al.,2022).However,the roles of endogenous CCK and CCK receptors in regulating hippocampal function at electrophysiological and behavioral levels have received less attention. 展开更多
关键词 abundant FUNCTIONS modulator
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Calcium-sensitive protein MLC1 as a possible modulator of the astrocyte functional state
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作者 Elena Ambrosini Angela Lanciotti Maria Stefania Brignone 《Neural Regeneration Research》 SCIE CAS 2025年第7期2008-2010,共3页
Astrocytes,the main population of glial cells in the central nervous system(CNS),exert essential tasks for the control of brain tissue homeostasis,supporting neuron and other glial cell activity from the developmental... Astrocytes,the main population of glial cells in the central nervous system(CNS),exert essential tasks for the control of brain tissue homeostasis,supporting neuron and other glial cell activity from the developmental stage to adult life.To maintain the optimal functionality of the brain,astroglial cells are particularly committed to reacting to every change in tissue homeostatic conditions,from mild modifications of the physiological environment,a process called astrocyte activation,to the more severe alterations occurring in pathological situations causing astrocyte reactivity or reactive astrogliosis(Escartin et al.,2021).During these reactive states,astrocytes mount an active,progressive response encompassing morphological,molecular,and interactional remodeling,leading to the acquisition of new functions and the loss of others,whose intensity,duration,and reversibility are dependent on the nature of the stimulus and regulated in a context-specific manner. 展开更多
关键词 alterations modulator MAINTAIN
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The Emerging Influence of Intestinal Microecological Dynamics on the Pathogenesis and Progression of Hepatic Chronic Pathologies:Current Scientific Perspectives
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作者 Shaoyan Qin 《Journal of Clinical and Nursing Research》 2025年第7期193-201,共9页
The intestinal microbiome,often characterized as humanity’s“secondary genome,”possesses a genetic repertoire that dwarfs the coding capacity of the human genome by orders of magnitude.The essential architecture of ... The intestinal microbiome,often characterized as humanity’s“secondary genome,”possesses a genetic repertoire that dwarfs the coding capacity of the human genome by orders of magnitude.The essential architecture of this system is constituted by a vast phylogenetic tapestry of luminal microorganisms,whose dynamic symbiosis serves as a critical determinant of intestinal mucosal homeostasis and functional fidelity.The past decade has witnessed a paradigm shift in biomedical sciences,wherein technological breakthroughs in microbial single-cell genomics and spatial metatranscriptomics have unveiled the gut ecosystem’s pivotal role in host physiology.Emerging evidence from gut-liver interface research demonstrates how microbial-derived signals,facilitated by the portal circulatory nexus,mechanistically contribute to the initiation and perpetuation of chronic hepatopathies.This review elucidates the pathophysiological mechanisms through which intestinal dysbiosis propagates chronic hepatopathies,with the ultimate objective of informing novel diagnostic paradigms and therapeutic interventions. 展开更多
关键词 Viral hepatitis Alcoholic liver disease Metabolic-dysfunction associated fatty liver disease Gut microecology Fecal microbiota transplantation
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Broadband PZT electro-optic modulator
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作者 Peng Wang Hongyan Yu +9 位作者 Yujun Xie Jie Peng Chengyang Zhong Ang Li Zehao Guan Jungan Wang Chen Yang Yu Han Feng Qiu Ming Li 《Journal of Semiconductors》 2025年第3期8-11,共4页
As the demand for computing power in data centers continues to grow, balancing data transmitting speed and energy efficiency has emerged as a critical challenge. Highbandwidth, low-power interconnection schemes are in... As the demand for computing power in data centers continues to grow, balancing data transmitting speed and energy efficiency has emerged as a critical challenge. Highbandwidth, low-power interconnection schemes are increasingly recognized as core requirements for next-generation intelligent computing center designs^([1, 2]). For short-range optical interconnections of intra-chip and inter-chip—typically covering tens of meters or less—microring resonant modulators (MRM) are emerging as an ideal solution. 展开更多
关键词 COMPUTING INTERCONNECTION modulator
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Neurotensin Modulates Emotional Valence Assignment in the Basolateral Amygdala Through Neuromodulator Gain
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作者 Maimaitishalijiang Abudureheman Yu-Hao Xiao +1 位作者 Li-Zang Zeng Hong-Yan Geng 《Neuroscience Bulletin》 2025年第1期177-180,共4页
Based on previous experience,learning to avoid or seek certain specific stimuli again in the future is crucial for survival.Our brains are wired to assign a particular valence-either positive or negativeas a result of... Based on previous experience,learning to avoid or seek certain specific stimuli again in the future is crucial for survival.Our brains are wired to assign a particular valence-either positive or negativeas a result of sensory stimuli,and it is this valence that serves as the foundational motivation for our subsequent actions.Simply put,all motivational actions fall into two categories:pleasure-seeking behavior guided by positive emotional valence,and pain-avoiding behavior driven by negative emotional valence[1].The ability to shift from one emotional valence to another is an important characteristic of affective states,while the instability of emotional states underlies many psychiatric disorders,highlighting the clinical importance of managing and understanding these fluctuations.This ability to adapt emotional responses can be attained by modulating the gain across distinct neural pathways,thus enabling the nuanced and smooth assignment of valence through the strengthening or weakening of circuit activity[1,2]. 展开更多
关键词 EMOTIONAL MOTIVATION modulator
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A Study on the Modeling and Design of Sigma-Delta Modulator for High Precision ADC
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作者 Haodong Guo Longyu Li Xia Zhang 《Journal of Electronic Research and Application》 2025年第2期240-246,共7页
With the continuous improvement of signal processing accuracy requirements in modern electronic systems,the demand for high-precision analog-to-digital converters(ADCs)is increasing.Sigma-Delta modulator,as the most i... With the continuous improvement of signal processing accuracy requirements in modern electronic systems,the demand for high-precision analog-to-digital converters(ADCs)is increasing.Sigma-Delta modulator,as the most important component of high-precision ADC,is widely used in high-quality audio,high-precision instrument measurement,and other fields due to its advantages of high precision,strong noise resistance,and low hardware cost.This article designs a discrete structure third-order four-bit high-precision Sigma-Delta modulator through modeling,with an oversampling rate set to 512.Under ideal conditions,the simulation results show that the SDNR reaches 152.7db and the ENOB is 25.24bits.After introducing non-ideal noise,the system performance has decreased.The simulation results show that the SDNR is as high as 124.5db and the ENOB is 20.39bits.This indicates that the design can achieve high-precision conversion and provide assistance for further research in the future. 展开更多
关键词 Analog-to-digital converter Sigma-Delta modulator High precision Modeling design
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Femtosecond laser modulated into Bessel beam by spatial light modulator for Fresnel zone plate processing
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作者 DUAN Lian ZHOU Fang +3 位作者 KONG De-jian ZHANG Fan SUN Xiao-yan DUAN Ji-an 《Journal of Central South University》 2025年第2期469-482,共14页
Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,... Femtosecond laser processing is an important machining method for micro-optical components such as Fresnel zone plate(FZP).However,the low processing efficiency of the femtosecond laser restricts its application.Here,a femtosecond laser Bessel beam is proposed to process micro-FZP,which is modulated from a Gaussian beam to a Bessel annular beam.The processing time for FZP with an outer diameter of 60μm is reduced from 30 min to 1.5 min on an important semiconductor material gallium arsenide(GaAs),which significantly improves the processing efficiency.In the modulation process,a central ablation hole that has an adverse effect on the diffraction performance is produced,and the adverse effect is eliminated by superimposing the blazed grating hologram.Meanwhile,the FZP machined by spatial light modulator(SLM)has good morphology and higher diffraction efficiency,which provides a strong guarantee for the application of micro-FZP in computed tomography and solar photovoltaic cells. 展开更多
关键词 femtosend laser Fresnel zone plate spatial light modulator Bessel beam GAAS
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Synergistic Anti-Lung Cancer and Immunomodulatory Effects of Combined Extracts from Acanthopanax sessiliflorus,Phragmites communis,and Pinus densiflora
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作者 Anjali Kariyarath Valappil Reshmi Akter +7 位作者 Muhammad Awais Dong Uk Yang Daehyo Jung Li Ling Eun Kim Kyu Hyeong Yoon Yoon Ok Lee Deok Chun Yang 《BIOCELL》 2025年第9期1771-1795,共25页
Objectives:The phytochemical investigation of traditional herbal medicines holds significant promise for modern drug discovery,particularly in cancer therapy.This study aimed to evaluate the cytotoxicity,apoptosis ind... Objectives:The phytochemical investigation of traditional herbal medicines holds significant promise for modern drug discovery,particularly in cancer therapy.This study aimed to evaluate the cytotoxicity,apoptosis induction,and immune-modulatory activities of extracts from three herbal medicines with historical use in traditional medicine—Acanthopanax sessiliflorus,Phragmites communis,and Pinus densiflora,as well as their combined extract(GMAS 01/COM),on human lung cancer cells(A549)and normal cell lines,including murine macrophages(RAW 264.7)and human keratinocytes(HaCaT).Methods:Plant extracts were prepared using aqueous extraction,sonication,and rotary evaporation.The total phenolic and flavonoid contents were quantified using the Folin-Ciocalteu and AlCl3 colorimetric methods,respectively.Antioxidant potential was evaluated via 2,2-Diphenyl-1-picrylhydrazyl(DPPH)scavenging and reducing power assays.Cytotoxicity was assessed using an MTT assay,while reactive oxygen species(ROS)generation was quantified using a 2′,7′-Dichlorodihydrofluorescein diacetate(DCFH-DA)assay.Anticancer properties,including colony formation inhibition and migration suppression,were examined using colony formation and wound healing assays.The expression of apoptotic and inflammatory mediators was analysed through qPCR.Results:GMAS 01 selectively induced apoptosis in A549 cells without cytotoxic effects on RAW264.7 and HaCaT cells.Mechanistically,it elevated intracellular ROS and activated the intrinsic mitochondrial apoptotic pathway,evidenced by p53 upregulation,increased Bax,and decreased Bcl-2 expression.GMAS 01 also significantly inhibited colony formation and migration in A549 cells.In RAW264.7 cells,it reduced nitric oxide(NO)production and downregulated iNOS,COX-2,IL-6,and IL-8,indicating strong immunomodulatory activity.Conclusion:GMAS 01 exhibits potent antioxidant,anti-inflammatory,and anticancer effects,likely mediated through ROS-induced mitochondrial apoptosis.However,mechanistic interpretations are limited by the absence of protein-level validation and pathway inhibition studies.Upcoming studies should aim to verify the underlying mechanisms and evaluate their potential for real-world application. 展开更多
关键词 ANTIOXIDANTS ROS lung cancer immune modulation Acanthopanax sessiliflorus Phragmites communis Pinus densiflora APOPTOSIS
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A “Tonebusting” Technique to Build a DAC from a First-Order Digital ΣΔ Modulator
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作者 Yves Leduc Gilles Jacquemod +1 位作者 Yoann Charlon Fabrice Muller 《Journal of Electronic Research and Application》 2025年第4期8-13,共6页
In this paper,we present a novel first-order digitalΣΔconverter tailored for digital-to-analog applications,focusing on achieving both high yield and reduced silicon estate.Our approach incorporates a substantial le... In this paper,we present a novel first-order digitalΣΔconverter tailored for digital-to-analog applications,focusing on achieving both high yield and reduced silicon estate.Our approach incorporates a substantial level of dithering noise into the input signal,strategically aimed at mitigating the spurious frequencies commonly encountered in such converters.Validation of our design is performed through simulations using a high-level simulator specialized in mixed-signal circuit analysis.The results underscore the enhanced performance of our circuit,especially in reducing spurious frequencies,highlighting its efficiency and effectiveness.The final circuit exhibits an effective number of bits of 13. 展开更多
关键词 First-order digital SD modulator Digital to analog converter Spurious frequencies Dithering
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Modulatory role of vitamin D in atopic dermatitis and allergic rhinitis
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作者 Chandra Sekhar Devulapalli 《World Journal of Clinical Pediatrics》 2025年第4期189-195,共7页
Vitamin D,beyond its classical role in calcium homeostasis,has emerged as a key regulator of immune function and epithelial barrier integrity.Its deficiency during early childhood—a critical period for immune maturat... Vitamin D,beyond its classical role in calcium homeostasis,has emerged as a key regulator of immune function and epithelial barrier integrity.Its deficiency during early childhood—a critical period for immune maturation—has been increasingly implicated in the development of atopic diseases.While extensively studied in asthma,its role in non-respiratory allergic conditions such as atopic dermatitis(AD)and allergic rhinitis(AR)remains comparatively underexplored.This minireview synthesizes current mechanistic and clinical evidence on vitamin D in pediatric AD and AR.In AD,vitamin D promotes epidermal barrier function through upregulation of filaggrin and ceramide synthesis,and enhances antimicrobial defense via induction of antimicrobial peptides.Observational studies consistently report lower serum 25-hydroxyvitamin D in affected children,particularly those with allergic sensitization.Select randomized controlled trials suggest clinical improvement with supplementation,especially at doses>2000 IU/day in deficient individuals.In AR,epidemiological data indicate stronger inverse associations with seasonal(pollen-induced)disease.Proposed mechanisms include modulation of dendritic cells,regulatory T cells,T helper 2 cytokines,and mucosal barrier integrity.The shared immunopathogenesis of AD and AR underscores vitamin D’s relevance.Although promising,clinical evidence remains heterogeneous.Future research should prioritize phenotype-stratified trials to clarify optimal dosing,timing,and individual response determinants,including genetics and microbiome composition. 展开更多
关键词 Vitamin D Atopic dermatitis Allergic rhinitis Pediatric allergy Immune modulation Epithelial barrier function Vitamin D receptor Allergic sensitization Earlylife immunity Genetic polymorphism
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Galactose-modified small molecule modulator targets RORαto enhance circadian rhythm and alleviate periodontitis-associated alveolar bone loss
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作者 Guangxia Feng Zhiwen Liao +15 位作者 Yifan Wang Qingming Tang Nayun Li Cheng Li Yuqing Liu Renlong Liu Mingjian Cui Wenjie Fan Ying Yin Lingkui Meng Jing Zeng Zetao Chen Guanzheng Luo Peng Xiang Qian Wan Lili Chen 《Bone Research》 2025年第6期1499-1512,共14页
Circadian rhythm disorders are associated with dysfunction in inflammatory diseases,and targeted regulation of the circadian rhythm could serve as an intervention strategy.RORα/γ,as core components of circadian cloc... Circadian rhythm disorders are associated with dysfunction in inflammatory diseases,and targeted regulation of the circadian rhythm could serve as an intervention strategy.RORα/γ,as core components of circadian clock genes,positively modulate the key circadian molecule BMAL1.In this study,Gala-SR,a potent small-molecule compound designed to effectively regulate circadian rhythms,was synthesized through a monosaccharide modification prodrug strategy via a hydrolysable conjugation of galactose onto SR1078,an unique synthetic agonist of RORα/γ.Compared with SR1078,Gala-SR exhibited significantly greater aqueous solubility,cytocompatibility,pharmacokinetic characteristics and efficacy in the targeted activation of RORα.Importantly,Gala-SR ameliorated rhythm disorders by enhancing amplitude of the circadian rhythm both in vitro and in vivo.In circadian rhythm disordered mice with periodontitis,Gala-SR restored local circadian rhythm and mitigated inflammation in periodontal tissue in a circadian clock-dependent manner,and alleviated alveolar bone loss.Our study demonstrates that Gala-SR exhibits great promise in restoration of circadian rhythm and could potentially serve as a targeted therapeutic intervention for treating inflammatory diseases arising from disruptions in circadian rhythm.This work provides a feasible paradigm for the development and translational application of small molecule modulators targeting circadian rhythms. 展开更多
关键词 monosaccharide modification prodrug strategy targeted regulation circadian rhythm hydrolysable conjugation circadian rhythm disorders ROR galactose modified small molecule modulator regulate circadian rhythmswas circadian clock
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阴道微生态失衡、高危型人乳头瘤病毒感染对宫颈病变的影响
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作者 朱兆霞 李世丹 +3 位作者 黄友娜 王瑞辉 孟祥蕾 郑晓瑛 《妇儿健康导刊》 2026年第1期32-36,共5页
目的 探讨阴道微生态失衡、高危型人乳头瘤病毒(HPV)感染对宫颈病变的影响。方法 选取2021年4月至2023年11月在诸城市妇幼保健院妇科门诊就诊的600例女性为研究对象,根据是否有宫颈病变分为病变组、无病变组。比较两组阴道微生态和高危... 目的 探讨阴道微生态失衡、高危型人乳头瘤病毒(HPV)感染对宫颈病变的影响。方法 选取2021年4月至2023年11月在诸城市妇幼保健院妇科门诊就诊的600例女性为研究对象,根据是否有宫颈病变分为病变组、无病变组。比较两组阴道微生态和高危型HPV感染情况,采用多因素logistic回归分析宫颈病变的危险因素。结果 600例中,宫颈病变103例,发生率为17.17%。病变组年龄、长期口服短效避孕药占比高于无病变组(P<0.05);病变组过氧化氢、唾液酸苷酶、白细胞酯酶、凝固酶阳性及阴道清洁度3~4级、高危型HPV感染占比均高于无病变组(P<0.05);多因素分析结果显示,过氧化氢阳性、唾液酸苷酶阳性、白细胞酯酶阳性、凝固酶阳性、阴道清洁度3~4度、高危型HPV感染为宫颈病变的独立危险因素(P<0.05)。结论 阴道微生态失衡、高危型HPV感染是宫颈病变的危险因素,恢复阴道微生态环境平衡、抗HPV感染可有效降低宫颈病变的发生风险。 展开更多
关键词 高危型人乳头瘤病毒感染 阴道微生态 宫颈病变 影响因素
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结合积分与旋转调制的抗晃动对准
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作者 杨泳 李东霖 +2 位作者 付玉洁 孔令兵 徐开俊 《电光与控制》 北大核心 2026年第2期90-95,共6页
针对捷联惯导系统在晃动环境下抗干扰能力不足导致对准精度不高的问题,设计并实现一种结合积分与旋转调制的抗晃动对准方法。首先,分析旋转调制技术在误差补偿方面的原理,并构建了晃动基座情况下惯性器件的输出模型;随后,推导了基于积... 针对捷联惯导系统在晃动环境下抗干扰能力不足导致对准精度不高的问题,设计并实现一种结合积分与旋转调制的抗晃动对准方法。首先,分析旋转调制技术在误差补偿方面的原理,并构建了晃动基座情况下惯性器件的输出模型;随后,推导了基于积分的惯性系粗对准,通过姿态更新消除了角晃动的影响,并通过对比力积分减弱了线振动的干扰;最后,建立了晃动条件下的系统状态和量测方程,采用反馈校正的Kalman滤波算法进行精对准的最优估计。实验结果表明,相较于仅使用旋转调制抗晃动对准方法,所提方法在晃动环境下的水平精度和天向精度均有所提高。 展开更多
关键词 捷联惯导系统 旋转调制 晃动基座 初始对准
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阳极氧化制备多孔氧化铝过程中碳棒导电行为与机制
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作者 杨淑敏 李欣 +1 位作者 顾建军 岂云开 《物理学报》 北大核心 2026年第1期375-385,共11页
多孔氧化铝薄膜因其优异的介电、机械和光学性能,广泛应用于电子器件、催化载体等领域.阳极氧化是制备高质量多孔氧化铝薄膜的主要方法,常用的碳棒对电极的导电行为和机制是影响薄膜微结构及其物性的一个重要因素.本文选取质量分数为6%... 多孔氧化铝薄膜因其优异的介电、机械和光学性能,广泛应用于电子器件、催化载体等领域.阳极氧化是制备高质量多孔氧化铝薄膜的主要方法,常用的碳棒对电极的导电行为和机制是影响薄膜微结构及其物性的一个重要因素.本文选取质量分数为6%的磷酸为电解液,圆形铝箔为阳极,碳棒作为对电极,电极间距为15 cm,氧化时间为40 s,实验研究了氧化电压在100—140 V下碳棒的导电行为.实验结果显示,氧化铝薄膜的孔洞深度和孔径由薄膜中心向外呈对称性递减分布.当氧化电压低于110 V时,制备的氧化铝薄膜孔深和孔径由薄膜中心向外渐变梯度较小,宏观上呈现均一的结构色;当氧化电压达到110 V时,氧化铝薄膜孔深和孔径渐变梯度较大,薄膜呈现虹彩环形的结构色,随着氧化电压的增大,薄膜孔深和孔径渐变梯度增加,结构色环的数量增多,可见光内色域宽度显著增大.利用电磁学和电化学理论计算了碳棒在不同氧化电压下的导电行为并分析了其导电机制,得到了碳棒具有“准点电极”导电特性的结论,揭示了碳棒上点电极位置的选择遵循两极间的电阻最小原则.这一发现不仅丰富了阳极氧化的电化学理论,还为制备多功能的氧化铝薄膜提供了理论和实验支撑. 展开更多
关键词 多孔氧化铝 准点电极 电流密度梯度 结构色调控
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基于ALD—YOLO的自然场景下苹果叶片病害检测方法研究
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作者 刘霞 周家横 古庆辉 《中国农机化学报》 北大核心 2026年第1期52-61,共10页
针对自然场景下苹果叶片病害检测存在背景噪声、病害表征相似及小尺度目标多等因素导致模型检测精度不足的挑战,提出一种ALD—YOLO算法,旨在实现自然场景下苹果叶片病害的精准检测。首先,提出一种CBAM—G注意力机制并嵌入主干网络,使网... 针对自然场景下苹果叶片病害检测存在背景噪声、病害表征相似及小尺度目标多等因素导致模型检测精度不足的挑战,提出一种ALD—YOLO算法,旨在实现自然场景下苹果叶片病害的精准检测。首先,提出一种CBAM—G注意力机制并嵌入主干网络,使网络在特征提取阶段聚焦病害关键特征并降低图片形变产生的影响。其次,将多层次特征信息输入OCR模块并反馈给头部网络,使模型获取更为丰富的像素级语义信息从而精准分类。最后,提出一种动态赋权IoU损失函数,通过为小尺度目标动态赋权来提高小尺度目标损失,进而提升对小尺度目标的检测精度。结果表明,该算法在自制数据集上的精确率为84.93%、召回率为72.88%、平均精度均值为77.48%、处理速度达24.74帧/s。 展开更多
关键词 苹果 叶片病害检测 YOLOX 自然场景 OCR模块
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计及储能调频能力的高比例新能源电力系统优化调度
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作者 林俐 丁文敏 +2 位作者 唐传伟 马笑寒 赵冬梅 《华北电力大学学报(自然科学版)》 北大核心 2026年第1期1-11,I0001,I0002,共13页
随着可再生能源大量并网,其波动性、间歇性给电网调峰调频带来了困难和挑战,而储能作为优质的调节资源可以缓解日益增长的调峰与频率响应压力。据此,本文分析多源联合系统的惯性响应和一次调频机理,研究电化学储能的频率响应能力,确定... 随着可再生能源大量并网,其波动性、间歇性给电网调峰调频带来了困难和挑战,而储能作为优质的调节资源可以缓解日益增长的调峰与频率响应压力。据此,本文分析多源联合系统的惯性响应和一次调频机理,研究电化学储能的频率响应能力,确定其非调峰阶段的基本调频容量;以最大化利用储能为目标,对电化学储能荷电状态进行分区,提出一种基于SoC的储能调频容量增量划分方法。以净负荷波动最小为目标确定储能调频的时间区间、容量;以系统运行成本最低最大消纳新能源为目标构建计及储能调频能力的高比例新能源电力系统双层优化调度模型;最后,选取改进IEEE-39节点算例系统进行分析,验证所提模型的有效性和可行性。 展开更多
关键词 储能 优化调度 调峰调频 新能源消纳 多源联合
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用于海马体保护预防性全脑照射的Edge-VMAT、Halcyon-VMAT和HyperArc计划的剂量学对比
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作者 王美娇 刘嘉城 +4 位作者 姚凯宁 蒲亦晨 张健 刘卓伦 杜乙 《中国医学物理学杂志》 2026年第2期141-147,共7页
目的:通过量化3种放疗计划方法之间的剂量学差异,研究多维度的剂量学分析和治疗效率评估,旨在建立标准化、高质量的海马体保护预防性全脑照射(HS-PCI)临床计划设计模板,从而提升计划设计质量并优化临床治疗效率。方法:20例HS-PCI患者,... 目的:通过量化3种放疗计划方法之间的剂量学差异,研究多维度的剂量学分析和治疗效率评估,旨在建立标准化、高质量的海马体保护预防性全脑照射(HS-PCI)临床计划设计模板,从而提升计划设计质量并优化临床治疗效率。方法:20例HS-PCI患者,每例患者均设计3种放疗计划,比较3种计划(Edge-VMAT、Halcyon-VMAT和HyperArc)的靶区剂量、危及器官剂量和机器跳数的差异。结果:HyperArc计划的PTV D_(98%)和V_(95%)最高,显著优于Edge-VMAT和Halcyon-VMAT计划(P<0.05)。HyperArc计划PTV Dmean最高,但3种计划间差异无统计学意义(P>0.05)。Edge-VMAT计划PTV D_(max)剂量最低,但组间差异没有统计学意义(P>0.05)。PTV D_(min)结果显示Halcyon-VMAT计划剂量最高,与Edge-VMAT和HyperArc计划均有统计学意义(P<0.05)。PTV D2%结果显示Edge-VMAT计划剂量最低,与Halcyon-VMAT和HyperArc计划均有统计学意义(P<0.05)。计划质量评估结果显示,HyperArc计划的适形度指数最高,均匀性指数最低,均显著优于其他两种计划(P<0.05)。3种放疗计划的海马体D_(max)中位数均为17 Gy,HyperArc与Halcyon-VMAT计划间差异有统计学意义(P<0.05)。对于海马体Dmean和D_(min),HyperArc计划剂量最低,Edge-VMAT与Halcyon-VMAT、Halcyon-VMAT与HyperArc组间均有统计学意义(P<0.05)。左侧和右侧眼晶体、左侧视神经和视交叉的D_(max),以及左侧和右侧眼球的Dmean在3种放疗计划间均有统计学意义(P<0.05)。结论:HyperArc计划靶区具有更优的适形度和覆盖率,同时显著降低危及器官的剂量,可作为HS-PCI治疗的有效方案。 展开更多
关键词 HyperArc Halcyon 海马体保护 预防性全脑放疗 容积旋转调强放疗
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