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Six Amino Acids among Natural Moisturizing Factors Responsible for Skin Hydration: Improvement and Anti-Aging of Skin by Galactomyces Ferment Filtrate-PiteraTM Containing Skin Moisturizer
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作者 Kukizo Miyamoto Yoko Munakata +4 位作者 Keisuke Fujii Wang Summer Ley Yang Suda Sudarsana Masutaka Furue 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第2期113-127,共15页
Background: Natural moisturizing factors (NMFs) are filaggrin-derived components in the cornified layer that are critical for maintaining healthy skin moisturization and barrier function. However, studies have reporte... Background: Natural moisturizing factors (NMFs) are filaggrin-derived components in the cornified layer that are critical for maintaining healthy skin moisturization and barrier function. However, studies have reported conflicting findings on the relationship between NMF levels and aging, while few studies have investigated this relationship clinically. To fill this research gap, we determined the levels of major NMF components such as free amino acids, pyrrolidone carboxylic acid, and urocanic acids, and individually verified their relationships with skin hydration, barrier function, age, and skin aging. Purpose: The objective of this study was to clinically investigate the relationship between NMF components levels and skin aging in facial skin. The main NMF components were obtained from facial skin and quantified. We then selected NMF components showing strong relationships to skin hydration, and analyzed the relationships of the levels of these selected NMF components with signs of skin aging, namely, texture, pores, wrinkles, and dullness (L-value). We also examined the efficacy of treatment with a skin care formula (SK-II Facial Treatment Essence, called SK-II FTE hereafter) including Galactomyces ferment filtrate (GFF, PiteraTM) on the selected NMF component levels associated with skin hydration and barrier function, and the signs of skin aging of texture, pores, wrinkles, and dullness (L-value). Method: We conducted two clinical trials in this research. In Study 1, we measured 23 NMF components using tape-stripped cornified layer to quantify them via an HPLC method in 196 Asian females aged 20 to 59 (mean S.D., 38.6 9.4). Facial visual aging parameters [texture, pores, wrinkles, and dullness (L-value)], as well as elasticity (R7), skin hydration, and TEWL, were quantified using facial skin imaging and skin physical property measurement devices. Study 2 was performed to evaluate whether the facial application of SK-II FTE affects the NMF levels and skin aging parameters in 63 Asian female volunteers aged 20 to 55 (38.4 9.03). During the course of Study 2, 0.6 mL of SK-II FTE was applied to the face twice daily in the morning and afternoon. Skin measurements were performed at the start of the day (baseline) and at week 8. Results: In Study 1, we examined the stratum corneum levels of 23 NMF components comparing to the skin hydration status in 196 female subjects. The subjects were divided into two groups using the median of each measured NMF component. Skin hydration values were compared between the two groups defined for each NMF component. The results showed that subjects with higher levels of six amino acids, alanine, arginine, asparagine, glutamine, glycine, and histidine, exhibited significantly higher skin hydration than those with lower amino acid levels. No significant differences in skin hydration values were found for the other 17 NMF components. We then analyzed whether the sum of these six amino acid NMF components (called 6-AA-NMFs, hereafter) is affected by aging. The 6-AA-NMF level peaked in the subjects aged 25-29, and then gradually and significantly decreased with age. Interestingly, the 6-AA-NMF level was significantly correlated with the skin hydration value, but not with TEWL. In addition, the 6-AA-NMF level demonstrated significant correlations with the signs of skin aging of texture, pores, wrinkles, and dullness (L-value). Then, in Study 2, we examined whether the daily application of SK-II FTE affects the 6-AA-NMF level and visual aging parameters in 63 females. SK-II FTE demonstrated significant increases of the levels of 6-AA-NMFs and each of its components associated with hydration and barrier function, and improvements of skin texture, pores, wrinkles, and dullness (L-value) during the 8 weeks of treatment of facial skin. Conclusion: These clinical studies with large numbers of subjects across a wide age range revealed that six amino acids as NMF components were highly correlated with facial skin hydration in the stratum corneum. The levels of these six NMF components were also found to decrease at ages after the 30 s and were significantly correlated with major signs of skin aging. Notably, these six NMF components (6-AA-NMFs) were increased by SK-II FTE treatment associated with improvements of skin hydration and signs of skin aging, namely, texture, pores, wrinkles, and dullness (L-value). These studies were limited by the lack of investigation of why some NMF components were not associated with skin hydration. More clinical trials examining various NMF components and their relationship with aging are anticipated. 展开更多
关键词 NMF Amino Acid Visual Aging Parameter Hydration AGING Texture Pore Wrinkle dullness Galactomyces Ferment Filtrate PiteraTM SK-II Facial Treatment Essence
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Introgression of lac6/tl1/du13 improves the palatability of japonica rice
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作者 Yong Yang Tao Zhang +9 位作者 Yuliang Shi Yan Lu Qianfeng Li Xiaolei Fan Lichun Huang Lu Chen Xuetang Song Qing Liu Changquan Zhang Qiaoquan Liu 《The Crop Journal》 SCIE CSCD 2024年第4期1259-1265,共7页
Amylose content(AC)is a crucial determinant of the eating and cooking quality(ECQ)of rice,with low AC varieties exhibiting a softer texture and greater stickiness-attributes that enhance palatability and are desirable... Amylose content(AC)is a crucial determinant of the eating and cooking quality(ECQ)of rice,with low AC varieties exhibiting a softer texture and greater stickiness-attributes that enhance palatability and are desirable in specific culinary contexts.To harness these traits,significant efforts have been made to manipulate AC to improve rice ECQ.Our research utilized the MutMap+approach to identify LAC6/TL1,a gene that is an allele of Du13,responsible for low AC.LAC6 encodes a C2H2 zinc finger protein,which specifically increases the splicing efficiency of the Wxb allele without affecting the Wxa allele.Functional studies of LAC6 revealed that its proper integration could rectify the undesirable AC phenotype,whereas mutations within this gene led to reduced AC and were associated with shorter grain length and decreased thousand-grain weight.Despite these drawbacks,such mutations positively impact rice palatability,presenting a trade-off between grain size and eating quality.To address the challenges posed by the reduced grain weight associated with LAC6 mutations,we developed a specific molecular marker for LAC6,which has been effectively used in breeding programs to select lac6/tl1/du13 homozygous individuals with larger grain size.Our findings demonstrate that the“small grain”trait associated with lac6/tl1/du13 can be effectively mitigated through combined phenotype-based and marker-assisted selection.This study highlights the potential of lac6/tl1/du13 as a valuable gene for breeding novel,high-quality soft rice varieties through targeted breeding strategies. 展开更多
关键词 Rice Dull endosperm Amylose content WX BREEDING
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粳稻低直链淀粉dull基因的遗传分析 被引量:15
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作者 赵国珍 刘吉新 《西南农业学报》 CSCD 北大核心 1998年第3期1-4,共4页
为了弄清控制粳稻低直链淀粉含量的dul基因的遗传机制,利于选育粳稻优质米新品种,我们利用含低直链淀粉的材料与直链淀粉含量中或高的品种杂交,调查F2种子世代的dul粒和非dul粒以及F3种子世代的dul株和非dul株,... 为了弄清控制粳稻低直链淀粉含量的dul基因的遗传机制,利于选育粳稻优质米新品种,我们利用含低直链淀粉的材料与直链淀粉含量中或高的品种杂交,调查F2种子世代的dul粒和非dul粒以及F3种子世代的dul株和非dul株,经χ2检验,符合3∶1的分离比;用F1与低直链淀粉含量的亲本回交,调查B1和B2的dul粒(株)和非dul粒(株)的分离比,经χ2检验,符合1:1。这一结果表明,控制低直链淀粉含量的dul基因是单隐性基因。到目前为止,已育成一个综合性状优良的粳稻软米新品系。 展开更多
关键词 粳稻 低直链淀粉 dull基因 遗传
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基于EMD方法的混沌信号中周期分量的提取 被引量:7
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作者 李鸿光 孟光 《应用数学和力学》 CSCD 北大核心 2006年第2期199-203,共5页
提出一种从Duffing振子产生的混沌信号中提取谐波分量的方法.依据任何信号由不同的固有简单振动模态组成的概念,利用经验模式分解(EMD)方法,将混沌信号分离为不同的内在模态函数(IMF),并在特定参数下从中分解出单一频率成分的谐波信号,... 提出一种从Duffing振子产生的混沌信号中提取谐波分量的方法.依据任何信号由不同的固有简单振动模态组成的概念,利用经验模式分解(EMD)方法,将混沌信号分离为不同的内在模态函数(IMF),并在特定参数下从中分解出单一频率成分的谐波信号,从而成功地将混沌信号和谐波分量分离.仿真实验都表明该方法非常有效. 展开更多
关键词 混沌信号 信号处理 周期分量 经验模式分解(EMD) Dulling方程
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利用Duffing振子估计多频信号参数 被引量:6
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作者 葛晓慧 黄进 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2008年第6期954-959,共6页
针对Duffing振子在混沌阈值附近对其临近频率的微小信号敏感而对其他信号免疫的特性,提出利用Duffing振子估计多频信号参数.将待测多频信号送入Duffing振子中,用多相位振子组法估计各分量的频率,再通过平均特征指数法得到各频率分量对... 针对Duffing振子在混沌阈值附近对其临近频率的微小信号敏感而对其他信号免疫的特性,提出利用Duffing振子估计多频信号参数.将待测多频信号送入Duffing振子中,用多相位振子组法估计各分量的频率,再通过平均特征指数法得到各频率分量对应的幅值和相位.该方法是一种时域分析方法,实现简单,估计精度高,对频率分量接近和低信噪比的多频信号同样适用.仿真结果和分析证明了该方法的有效性. 展开更多
关键词 参数估计 Dulling振子 混沌 特征指数 多频信号
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复杂策动力项对Duffing方程混沌系统相态的影响 被引量:2
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作者 胡艳飞 赵雪平 秦树洪 《吉林大学学报(地球科学版)》 EI CAS CSCD 北大核心 2005年第6期801-805,共5页
对经典Duffing方程在周期激励和限带白噪同时作用下的混沌性质进行分析。首先检测出无噪声时系统的临界状态和周期状态的周期激励的幅值,然后分别固定这两个特殊幅值,改变限带白噪的幅值,利用时间历程曲线辅助分析相态图的变化;再固定... 对经典Duffing方程在周期激励和限带白噪同时作用下的混沌性质进行分析。首先检测出无噪声时系统的临界状态和周期状态的周期激励的幅值,然后分别固定这两个特殊幅值,改变限带白噪的幅值,利用时间历程曲线辅助分析相态图的变化;再固定限带白噪的幅值,改变周期激励的幅值,借助时间历程曲线分析相态图的变化。结果表明:系统只输入周期激励时,随着周期激励幅值的增大,系统依次呈现同宿状态、混沌状态和周期状态;系统处在临界状态时,输入限带白噪声,随着限带白噪声幅值的增大,相态图的轨线运动范围增大。 展开更多
关键词 Dulling方程 复杂策动力 混沌 相态
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受迫摆方程的伪概周期解 被引量:6
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作者 朴大雄 辛娜 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第4期573-575,共3页
利用伪概周期函数的性质和Banach压缩映像原理研究受迫摆方程的伪概周期解问题,证明伪概周期解的存在性及在条件‖y-π‖L∞<π2下的唯一性。
关键词 受迫摆方程 Dulling方程 伪概周期解 格林函数Banaeh压缩映像原理
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基于Henon系统和Duffing方程自同步与异结构同步的研究 被引量:2
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作者 刘振泽 田彦涛 曹辉 《合肥工业大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第6期728-731,共4页
文章基于线性系统的稳定性理论,分别采用连续型混沌系统和离散型混沌系统,对参考信号进行追踪控制;对比分析了Henon系统和Duffing方程在追踪正弦信号,以及实现自同步与异结构同步方面的性能;仿真结果证明了Duffing方程对于任意频率正弦... 文章基于线性系统的稳定性理论,分别采用连续型混沌系统和离散型混沌系统,对参考信号进行追踪控制;对比分析了Henon系统和Duffing方程在追踪正弦信号,以及实现自同步与异结构同步方面的性能;仿真结果证明了Duffing方程对于任意频率正弦信号追踪的可行性。 展开更多
关键词 混沌 Henon混沌系统 Dulling方程
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基于混沌理论的涡街微弱信号检测方法研究 被引量:3
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作者 郑丹丹 张涛 《传感技术学报》 CAS CSCD 北大核心 2007年第5期1103-1108,共6页
针对涡街流量传感器在小口径、低流速下信号微弱,易被强噪声淹没而难于提取的特点,提出了利用Duffing振子检测微弱信号的方法.通过仿真对涡街信号中含有白噪声以及谐波干扰的情况进行分析,仿真和实验均表明:这种基于混沌理论的微弱信号... 针对涡街流量传感器在小口径、低流速下信号微弱,易被强噪声淹没而难于提取的特点,提出了利用Duffing振子检测微弱信号的方法.通过仿真对涡街信号中含有白噪声以及谐波干扰的情况进行分析,仿真和实验均表明:这种基于混沌理论的微弱信号检测方法对涡街信号中较强的白噪声以及频差较大的谐波干扰具有很好的免疫力,并且通过计算最大Lya-punov指数的波动频率能够准确估计出涡街有用信号频率,实现低流速下涡街微弱信号检测. 展开更多
关键词 涡街流量传感器 信号检测Dulling振子Lyapunov指数
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基于混沌的频率测量仿真
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作者 于晓洋 张健 +2 位作者 吕宁 李龙锁 陈德运 《电子器件》 EI CAS 2006年第2期394-396,共3页
Duffing方程具有参数敏感性和初值敏感性,通过调节Duffing方程的参数和初值可以产生混沌现象,且被测信号和理想信号如果共同作用在Duffing方程上,可以产生有规律间歇混沌现象,利用这种现象就可以实现周期信号的频率测量。Duffing方程还... Duffing方程具有参数敏感性和初值敏感性,通过调节Duffing方程的参数和初值可以产生混沌现象,且被测信号和理想信号如果共同作用在Duffing方程上,可以产生有规律间歇混沌现象,利用这种现象就可以实现周期信号的频率测量。Duffing方程还具有对噪声的免疫力以及对频差较大的周期信号的免疫力等特点。通过仿真实验,结果表明利用混沌理论实现频率测量的可行性,测量误差被控制在0.006Hz以内;并且系统具有非常高的抗干扰性,信噪比可达-19dB。 展开更多
关键词 混沌 Dulling方程 频率 仿真
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求Duffing方程周期解的Mountain Pass方法 被引量:6
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作者 刘淑媛 吕显瑞 齐毅 《吉林大学学报(理学版)》 CAS CSCD 北大核心 2007年第4期519-523,共5页
研究一类超线性Duffing方程周期解的存在性及其数值求解方法.利用山路引理证明了超线性Duffing方程周期解的存在性,并给出一种求Duffing方程周期解的Mountain Pass算法及其具体算例.
关键词 山路引理 临界点 P.S.条件 MOUNTAIN Pass算法 超线性Dulling方程
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Duffing简谐振子同伦分析法求解 被引量:6
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作者 冯少东 陈立群 《应用数学和力学》 CSCD 北大核心 2009年第9期1015-1020,共6页
利用同伦分析方法求解了Duffing简谐振子,数值确定了变形方程中的辅助参数,得到了一族响应和频率的近似周期解,该解与精确解符合很好.结果表明,同伦分析法在求解强非线性振子时,仍然是一种行之有效的方法.
关键词 Dulling简谐振子 同伦分析法 近似解
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基于双耦合Duffing振子的随机相位正弦信号检测 被引量:6
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作者 代理 李健 +1 位作者 郑豫 孙涛 《成都信息工程学院学报》 2008年第1期50-53,共4页
首先采用双耦合混沌振子阵列实现了随机相位微弱正弦信号的检测,在此基础上,提出了新的检测方法,即利用单个双耦合混沌振子,通过临界到混沌及周期状态的变化检测随机相位微弱正弦信号并大致估计信号相位范围。该方法比双耦合混沌振子阵... 首先采用双耦合混沌振子阵列实现了随机相位微弱正弦信号的检测,在此基础上,提出了新的检测方法,即利用单个双耦合混沌振子,通过临界到混沌及周期状态的变化检测随机相位微弱正弦信号并大致估计信号相位范围。该方法比双耦合混沌振子阵列法简单,更易于实现。 展开更多
关键词 混沌 双耦合dulling振子 微弱信号检测 随机相位
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Studies on structural safety in stochastically excited Duffing oscillator with double potential wells 被引量:1
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作者 Chunbiao Gan Shimin He 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第5期577-583,共7页
The effects of the Gaussian white noise excitation on structural safety due to erosion of safe basin in Duffing oscillator with double potential wells are studied in the present paper. By employing the well-developed ... The effects of the Gaussian white noise excitation on structural safety due to erosion of safe basin in Duffing oscillator with double potential wells are studied in the present paper. By employing the well-developed stochastic Melnikov condition and Monte-Carlo method, various eroded basins are simulated in deterministic and stochastic cases of the system, and the ratio of safe initial points (RSIP) is presented in some given limited domain defined by the system's Hamiltonian for various parameters or first-passage times. It is shown that structural safety control becomes more difficult when the noise excitation is imposed on the system, and the fractal basin boundary may also appear when the system is excited by Gaussian white noise only. From the RSIP results in given limited domain, sudden discontinuous descents in RSIP curves may occur when the system is excited by harmonic or stochastic forces, which are different from the customary continuous ones in view of the firstpassage problems. In addition, it is interesting to find that RSIP values can even increase with increasing driving amplitude of the external harmonic excitation when the Gaussian white noise is also present in the system. 展开更多
关键词 Stochastic Dulling oscillator Basin erosion Structural safety Stochastic Melnikov condition RSIP
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谐和与噪声联合作用下Duffing振子的安全盆分叉与混沌 被引量:9
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作者 戎海武 王向东 +1 位作者 徐伟 方同 《物理学报》 SCIE EI CAS CSCD 北大核心 2007年第4期2005-2011,共7页
研究了软弹簧Duffing振子在确定性谐和外力和有界随机噪声联合作用下,系统安全盆的侵蚀和混沌现象.推导出系统的随机Melnikov过程,根据Melnikov过程在均方意义上出现简单零点的条件给出了系统出现混沌的临界值,然后用数值模拟方法计算... 研究了软弹簧Duffing振子在确定性谐和外力和有界随机噪声联合作用下,系统安全盆的侵蚀和混沌现象.推导出系统的随机Melnikov过程,根据Melnikov过程在均方意义上出现简单零点的条件给出了系统出现混沌的临界值,然后用数值模拟方法计算了系统的安全盆分叉点.结果表明,由于随机扰动的影响,系统的安全盆分叉点发生了偏移,并且使得混沌容易发生. 展开更多
关键词 Dulling振子 安全盆 分叉 混沌
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一类Duffing型泛函微分方程周期解的存在与唯一性 被引量:2
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作者 汪娜 《数学的实践与认识》 CSCD 北大核心 2009年第3期194-200,共7页
我们利用重合度理论,建立了一类Duffing型泛函微分方程存在唯一周期解的新结果.
关键词 周期解 时滞 Dulling型方程 重合度
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A Dull Life
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《Beijing Review》 2006年第5期15-,共1页
A single light bulb hangs precariously from the ceiling of Qiu Suokun's small room in Beijing. It illuminates a bed, a table and some chairs that take up most of the 10 square meters. The room has no heating syste... A single light bulb hangs precariously from the ceiling of Qiu Suokun's small room in Beijing. It illuminates a bed, a table and some chairs that take up most of the 10 square meters. The room has no heating system installed, and is warmed by a small stove, which makes little impression during Beijing's fiercely cold winter. "We have nothing to entertain us. In the evening, I like having a drink with Qiu, eating some peanuts and playing cards," Zhao Huobing told Beijing Review. Zhao arrived in Beijing wi... 展开更多
关键词 PHONE A Dull Life
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