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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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电流源型逆变器消除重叠区效应DPWM策略
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作者 严庆增 张子旭 +3 位作者 张龙龙 冯兴田 何金奎 赵仁德 《实验室研究与探索》 北大核心 2025年第12期1-6,62,共7页
针对传统断续脉宽调制(DPWM)策略应用于电流源型逆变器(CSI)时,虽能降低其开关损耗,但重叠区效应会加剧输出电流谐波畸变的问题,为在提升两电平CSI输出效率的同时改善输出电流质量,提出一种基于DPWM的CSI重叠区效应补偿策略。首先研究了... 针对传统断续脉宽调制(DPWM)策略应用于电流源型逆变器(CSI)时,虽能降低其开关损耗,但重叠区效应会加剧输出电流谐波畸变的问题,为在提升两电平CSI输出效率的同时改善输出电流质量,提出一种基于DPWM的CSI重叠区效应补偿策略。首先研究了CSI中DPWM的实现方法,将二值逻辑转化为三值逻辑以生成驱动信号;通过分析重叠区期间的换流路径,选取用零电流矢量对驱动信号进行钳位处理。在此基础上,根据三相桥臂输出电压关系,引入叠加矩形脉冲作为补偿分量,以补偿重叠区效应引起的电流偏差矢量。实验结果表明,所提出的消除重叠区效应DPWM方法能够有效减少驱动信号的脉冲数与开关损耗,同时能够消除重叠区效应,提升输出电流质量。 展开更多
关键词 电流源型逆变器 断续脉宽调制 重叠区效应 开关损耗
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基于改进DPWM的三电平逆变器多目标优化算法
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作者 柴锦 王伟胜 +2 位作者 卢家璇 刘通 陈阿莲 《电源学报》 北大核心 2025年第4期79-88,共10页
三电平逆变器在中高压场合受到了广泛关注,但是传统的连续脉宽调制CPWM(continuous pulse width modulation)方法具有开关损耗大、共模电压CMV(common-mode voltage)波动大、中点电位不平衡等缺点。为解决上述问题,在分析共模电压产生... 三电平逆变器在中高压场合受到了广泛关注,但是传统的连续脉宽调制CPWM(continuous pulse width modulation)方法具有开关损耗大、共模电压CMV(common-mode voltage)波动大、中点电位不平衡等缺点。为解决上述问题,在分析共模电压产生机理的基础上,推导出基于离散脉宽调制DPWM(discrete pulse width modu-lation)的共模电压抑制条件,提出1种改进的DPWM调制策略,其可在DPWM0~DPWM3调制下降低开关损耗的同时实现共模电压抑制。此外,在所提DPWM调制策略的基础上,探究了中点电位控制方法,最终实现了三电平逆变器的多目标优化控制。仿真和实验验证了所提DPWM控制策略的有效性。 展开更多
关键词 三电平逆变器 共模电压 离散脉宽调制 中点电位平衡
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应用于数字电源的高分辨率DPWM模块的设计
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作者 刘雪剑 邓红辉 +1 位作者 杨增辉 向鸿宇 《微电子学》 北大核心 2025年第2期256-262,共7页
设计了一种基于TSMC 0.18μm CMOS工艺的高分辨率数字脉冲宽度调制器(Digital Pulse Width Modulation,DPWM),基于传统的计数器-比较器型结构,结合辗转相减延时链设计了一种新型的混合DPWM架构,引入Σ-Δ,有效得提高了DPWM的分辨率,其... 设计了一种基于TSMC 0.18μm CMOS工艺的高分辨率数字脉冲宽度调制器(Digital Pulse Width Modulation,DPWM),基于传统的计数器-比较器型结构,结合辗转相减延时链设计了一种新型的混合DPWM架构,引入Σ-Δ,有效得提高了DPWM的分辨率,其中使用计数器-比较器结构实现5 bits分辨位数,辗转相减延时链实现6 bits分辨位数,Σ-Δ扩充3 bits分辨位数。仿真结果表明,所设计的新型混合架构DPWM可以正常工作在1 MHz开关频率环境下,可实现14 bits的分辨率,时间分辨率为61 ps,需要输入时钟频率32 MHz,只使用了17个延时单元模块,DPWM输出存在误差时间仅有50 ps。 展开更多
关键词 dpwm 高分辨率 辗转相减延时链 Σ-Δ
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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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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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Manipulating Scattering Performance of Offshore Structures in Water Waves Using a Wavelength Modulator
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作者 Zhigang Zhang Yunzhou Li +4 位作者 Guanghua He Zhengxiao Luan Qiang Zhao Jiming Zhang Juncheng Wang 《哈尔滨工程大学学报(英文版)》 2025年第6期1141-1149,共9页
Through active manipulation of wavelengths,a structure exposed to a water-wave field can achieve a target hydrodynamic performance.Based on the form invariance of the governing equation for shallow water waves,wavelen... Through active manipulation of wavelengths,a structure exposed to a water-wave field can achieve a target hydrodynamic performance.Based on the form invariance of the governing equation for shallow water waves,wavelength modulators have been proposed using the space transformation method,which enables wavelength manipulation by distributing an anisotropic medium that incorporates water depth and gravitational acceleration within the modulation space.First,annular wavelength modulators were designed using the space transformation method to reduce or amplify the wavelength of shallow water waves.The control method of wavelength scaling ratios was investigated.In addition to plane waves,the wavelength modulator was applied to manipulate the wavelength of cylindrical waves.Furthermore,the interactions between a vertical cylinder and modulated water waves were studied.Results indicate that the wavelength can be arbitrarily reduced or amplified by adjusting the dimensional parameters of the modulator.Additionally,the modulator is effective for plane waves and cylindrical waves.This wavelength modulator can enable the structure to achieve the desired scattering characteristics at the target wavelength. 展开更多
关键词 Water-wave field Scattering performance Space transformation method Wavelength modulator Anisotropic medium
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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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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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基于DPWM的开关电源并联供电系统 被引量:2
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作者 杨剑 曾国强 +2 位作者 葛良全 李强 罗群 《电源技术》 CAS CSCD 北大核心 2014年第1期139-141,共3页
为满足大功率低电压开关电源稳定、高效率和低纹波的要求,研究开关电源并联供电系统具有重要的意义。使用高性能的STM32控制器产生两路高精度、互补的DPWM信号,控制两路MOS管的导通时间,从而控制两路开关电源的分流,实现了两路开关电源... 为满足大功率低电压开关电源稳定、高效率和低纹波的要求,研究开关电源并联供电系统具有重要的意义。使用高性能的STM32控制器产生两路高精度、互补的DPWM信号,控制两路MOS管的导通时间,从而控制两路开关电源的分流,实现了两路开关电源的数字开关均流技术。任意一路开关电源出现故障时,能自动分配电流到另一路,使负载上的电压保持稳定,并设计了消除采样电阻上压降对输出电压影响的直流误差补偿电路。最后给出了电源模块的试验测量数据,验证了设计的可靠性、合理性,具有一定的实用价值。 展开更多
关键词 STM32 dpwm 数字开关均流 直流误差补偿 开关电源 并联供电
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三相并网逆变器内模控制的改进型GDPWM算法(英文) 被引量:4
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作者 安少亮 孙向东 +2 位作者 张琦 钟彦儒 任碧莹 《中国电机工程学报》 EI CSCD 北大核心 2013年第27期1-11,25,共11页
针对单位功率因数并网的三相逆变器,推导三相并网逆变器内模控制方程,建立逆变器输出侧功率因数角随逆变器输出电流幅值变化的函数关系,深入分析传统常规化不连续脉宽调制(general discontinuous pulse width modulation,GDPWM)的特点,... 针对单位功率因数并网的三相逆变器,推导三相并网逆变器内模控制方程,建立逆变器输出侧功率因数角随逆变器输出电流幅值变化的函数关系,深入分析传统常规化不连续脉宽调制(general discontinuous pulse width modulation,GDPWM)的特点,提出一种改进型最小开关损耗不连续调制(modified general discontinuous pulse width modulation,M-GDPWM)算法,该算法通过比较三相正弦参考电压之间的瞬时大小关系,或者逆变器输出三相电流的瞬时大小关系,来计算需要注入到三相正弦参考电压中的零序分量,从而无需像传统最小开关损耗不连续调制那样需要实时计算功率因数角,即可实现最小开关损耗控制。仿真与实验结果验证了所提M-GDPWM算法的正确性和有效性。 展开更多
关键词 三相并网逆变器 内模控制 不连续脉宽调制 功率因数角
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基于DPWM算法的三电平光伏逆变器效率提升研究 被引量:4
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作者 王青龙 刘红亮 +1 位作者 汪海涛 郭寅远 《自动化技术与应用》 2018年第12期92-97,共6页
并网逆变器作为光伏系统的核心部件,其转换效率显得尤为重要。文章通过介绍SVPWM和DPWM两种调制模式下控制策略及中点电位控制方法 ,详细分析逆变器不同调制策略下开关器件及滤波器损耗分布情况,提出了基于DPWM算法的效率提升方法 ,并在... 并网逆变器作为光伏系统的核心部件,其转换效率显得尤为重要。文章通过介绍SVPWM和DPWM两种调制模式下控制策略及中点电位控制方法 ,详细分析逆变器不同调制策略下开关器件及滤波器损耗分布情况,提出了基于DPWM算法的效率提升方法 ,并在50kW组串式光伏逆变器上进行了试验验证,通过对比分析效率、谐波等指标,最终验证了采用DPWM调制策略的可行性。 展开更多
关键词 转换效率 SVPWM dpwm 中点电位平衡控制 开关损耗
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一种基于DPWM的新型工模具修补机的研究 被引量:1
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作者 杨军伟 胡仲翔 《新技术新工艺》 北大核心 2002年第3期13-15,共3页
介绍了一种基于双重脉宽调制 ( DPWM)技术的新型模具修补机 ,它除了能充分发挥了原有工模具修补机的优点外 ,体积更小 ,重量更轻 。
关键词 dpwm 工模具 修补机 双重脉宽调制 维修
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