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Global gene expression profiling of perirenal brown adipose tissue whitening in goat kids reveals novel genes linked to adipose remodeling
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作者 Le Zhao Haili Yang +6 位作者 Minhao Li Min Xiao Xingchun Li Lei Cheng Wenqiang Cheng Meixi Chen Yongju Zhao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1008-1026,共19页
Background Brown adipose tissue(BAT)is known to be capable of non-shivering thermogenesis under cold stimulation,which is related to the mortality of animals.In the previous study,we observed that goat BAT is mainly l... Background Brown adipose tissue(BAT)is known to be capable of non-shivering thermogenesis under cold stimulation,which is related to the mortality of animals.In the previous study,we observed that goat BAT is mainly located around the kidney at birth,and changes to white adipose tissue(WAT)in the perirenal adipose tissue of goats within one month after birth.However,the regulatory factors underlying this change is remain unclear.In this study,we systematically studied the perirenal adipose tissue of goat kids in histological,cytological,and accompanying molecular level changes from 0 to 28 d after birth.Results Our study found a higher mortality rate in winter-born goat kids,with goat birthing data statistics.Then we used thermal imaging revealing high temperature in goat hips at postnatal 0 d and gradually decrease during 28 d.This is consistent with the region of perirenal BAT deposition and highlights its critical role in energy expenditure and body temperature regulation in goat kids.Additionally,we found a series of changes of BAT during the first 28 d after birth,such as whitening,larger lipid droplets,decreased mitochondrial numbers,and down-regulation of key thermogenesis-related genes(UCP1,DIO2,UCP2,CIDEA,PPARGC1a,C/EBPb,and C/EBPa).Then,we used RNA-seq found specific marker genes for goat adipose tissue and identified 12 new marker genes for BAT and 10 new marker genes for WAT of goats.Furthermore,12 candidate genes were found to potentially regulate goat BAT thermogenesis.The mechanism of the change of this biological phenomenon does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes.While apoptosis may play a limited role,it is largely not critical in this transition process.Conclusions We concluded that perirenal BAT plays a crucial role in thermoregulation in newborn goat kids,with notable species differences in the expression of adipose tissue marker genes,and we highlighted some potential marker genes for goat BAT and WAT.Additionally,the change from BAT to WAT does not involve a large-scale death of brown adipocytes and subsequent proliferation of white adipocytes. 展开更多
关键词 Adipose remodeling Brown adipose tissue Goat kids Key thermogenesis-related genes whitenING
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基于PCA和Whitening算法的水稻病害图像预处理研究 被引量:8
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作者 路阳 衣淑娟 +2 位作者 张勇 安杏杏 邵晓光 《黑龙江八一农垦大学学报》 2017年第2期97-101,共5页
水稻病害图像预处理在使用机器视觉技术对水稻病害智能诊断识别中至关重要。预处理效果直接影响水稻病害识别准确率。提出一种新的基于PCA和Whitening融合算法的水稻病害图像预处理方法。实验获取了水稻病害彩色图像和灰度图像的训练样... 水稻病害图像预处理在使用机器视觉技术对水稻病害智能诊断识别中至关重要。预处理效果直接影响水稻病害识别准确率。提出一种新的基于PCA和Whitening融合算法的水稻病害图像预处理方法。实验获取了水稻病害彩色图像和灰度图像的训练样本和测试样本,对获取的样本应用PCA降维,然后对降维后的样本随机取样,应用Whitening算法得到了相应的训练特征和测试特征。实验表明,该融合算法增强了预处理后的水稻病害图像样本对光照及亮度的鲁棒性,可有效提高病害识别准确率。 展开更多
关键词 PCA whitenING 水稻病害 图像预处理
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Potential risks of spectrum whitening deconvolution——compared with well-driven deconvolution 被引量:13
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作者 Li Guofa Zhou Hui Zhao Chao 《Petroleum Science》 SCIE CAS CSCD 2009年第2期146-152,共7页
Deconvolution is widely used to increase the resolution of seismic data. To compare the resolution ability of conventional spectrum whitening deconvolution to thin layers with that of welldriven deconvolution, a compl... Deconvolution is widely used to increase the resolution of seismic data. To compare the resolution ability of conventional spectrum whitening deconvolution to thin layers with that of welldriven deconvolution, a complex sedimentary geological model was designed, and then the simulated seismic data were processed respectively by each of the two methods. The amplitude spectrum of seismic data was almost white after spectrum whitening, but the wavelet resolution was low. The amplitude spectrum after well-driven deconvolution deviated from white spectrum, but the wavelet resolution was high. Further analysis showed that if an actual reflectivity series could not well satisfy the hypothesis of white spectrum, spectrum whitening deconvolution had a potential risk of wavelet distortion, which might lead to a pitfall in high resolution seismic data interpretation. On the other hand, the wavelet after well- driven deconvolution had higher resolution both in the time and frequency domains. It is favorable for high resolution seismic interpretation and reservoir prediction. 展开更多
关键词 Well-driven high resolution spectrum whitening DECONVOLUTION seismic wavelet
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Construction mechanism of whitenization weight function and its application in grey clustering evaluation 被引量:5
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作者 XIE Naiming SU Bentao CHEN Nanlei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期121-131,共11页
The clustering evaluation can be used to scientifically classify the objects to be evaluated according to the information aggregation of various evaluation rules. In grey weighted clustering evaluation, the index clus... The clustering evaluation can be used to scientifically classify the objects to be evaluated according to the information aggregation of various evaluation rules. In grey weighted clustering evaluation, the index clustering rule relies on the construction of the whitenization weight function, while the existing construction method of the linear function lacks the construction mechanism analysis and validity explanation. A normative construction principle is put forward by analyzing the construction mechanism of the function. Through proving the normative principle of the function,the basic modal function(BMF) is proposed and characterized by different function forms. Then, a new type of the whitenization weight function and its grey clustering evaluation model algorithm are given by studying the mechanism and nature of the construction of different forms of the function. Finally, the comparative study for self-innovation capability of defense science and technology industry(DSTI) is taken as an example. The results show that the different construction ways of the function have an effect on the clustering result. The proposed construction mechanism can better explain the index clustering rules and evaluation effectiveness,which will perfect the theoretical system of grey clustering evaluation and be applied to practice effectively. 展开更多
关键词 whitenization WEIGHT FUNCTION GREY system THEORY GREY CLUSTERING evaluation.
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Polarimetric whitening filter for POLSAR image based on subspace decomposition 被引量:2
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作者 Yang Jian Deng Qiming Huangfu Yue Zhang Weijie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第6期1121-1126,共6页
Speckle filtering is an indispensable pre-processing step for applications of polarimetric synthetic aperture radar (POLSAR), such as terrain classification, target detection, etc. As one of the most typical methods... Speckle filtering is an indispensable pre-processing step for applications of polarimetric synthetic aperture radar (POLSAR), such as terrain classification, target detection, etc. As one of the most typical methods, the polarimetric whitening filter (PWF) can be used to produce a minimum-speckle image by combining the complex elements of the scattering matrix, but polarimetric information is lost after the filtering process. A polarimetric filter based on subspaze decomposition which was proposed by Cu et al specializes in retrieving principle scattering characteristics, but the corresponding mean value of an image after filtering is not kept well. A new filter is proposed for improving the disadvantage based on subspace decomposition. Under the constraint that a weighted combination of the polarimetric SAR images equals to the output of the PWF, the Euclidean distance between an unfiltered parameter vector and a signal space vector is minimized so that noises can be reduced. It is also shown that the proposed method is equivalent to the subspace filter in the case of no constraint. Experimental results with the NASA/JPL airborne polarimetric SAR data demonstrate the effectiveness of the proposed method. 展开更多
关键词 speckle filtering synthetic aperture radar polarimetric polarimetric whitening filter subspace decomposition
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The Research Progress and Prospect Analysis of Germ-Remaining Rice Whitener 被引量:2
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作者 WAN Zhihua XIA Jiqing KANG Defu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第2期84-87,共4页
In this paper, the backdrop and significance of the research of germ-remaining rice whitener firstly were expatiated. Then, the study progress in China and overseas was summarized. Lastly, the research prospect of thi... In this paper, the backdrop and significance of the research of germ-remaining rice whitener firstly were expatiated. Then, the study progress in China and overseas was summarized. Lastly, the research prospect of this kind of whitener in China was analyzed. It is hoped that it can coach the design of germ-remaining rice whitener. 展开更多
关键词 germ-remaining rice whitening technics research progress prospect analysis
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The Three-region Method of Color Matching in the Presence of Fluorescent Whitening Agents 被引量:1
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作者 李戎 顾峰 陈东辉 《Journal of Donghua University(English Edition)》 EI CAS 2005年第4期123-128,共6页
An expression of reflectance of fluorescent dyes in emission region was used in this article. Through the analysis of the spectral radiance factor of fluorescent whitening agents(FWA), the color matching of FWA was st... An expression of reflectance of fluorescent dyes in emission region was used in this article. Through the analysis of the spectral radiance factor of fluorescent whitening agents(FWA), the color matching of FWA was studied and the three-region method of color matching method was put forward. The method was proved to be reliable for the dyes used and was easy to apply for the color matching of FWAs. 展开更多
关键词 fluorescent whitening agents fluorescent quantum efficiency color matching.
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A Double-Blind, Placebo Controlled Clinical Trial Evaluating the Efficacy and Safety of a New Skin Whitening Combination in Patients with Chloasma 被引量:8
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作者 Xi Wang Zhaoxia Li +2 位作者 Dan Zhang Li Li Seite Sophie 《Journal of Cosmetics, Dermatological Sciences and Applications》 2014年第2期92-98,共7页
Melasma (or chloasma) is a hyperpigmentation disorder predominantly affecting sun-exposed skin in women, and is often refractory to treatment. The objective was to evaluate the efficacy and safety of a new whitening f... Melasma (or chloasma) is a hyperpigmentation disorder predominantly affecting sun-exposed skin in women, and is often refractory to treatment. The objective was to evaluate the efficacy and safety of a new whitening formula for the treatment of chloasma. This?single centre, double-blind, placebo controlled, bilateral (split-face) comparison, was conducted on 44 Chinese subjects with chloasma during the winter season. The test formula was applied twice a day, for 12 weeks on left side of the face and a placebo formula on the right side of the face. Assessments included the use of the hemi-MASI (split-face Melasma Area Severity Index), both ultraviolet and standard photography, together with clinical evaluations of efficacy and safety at T0, T6 and T12 weeks. A significant difference between the 2-hemi-MASI was noticed after 6 and 12 weeks of treatment. This result was confirmed by the clinical evaluation of the dermatologists who recorded a significant improvement in the half-face treated with the new whitening formula compared with that treated with placebo (p = 0.003). The tolerance of the new formula was recorded as excellent by 82% of subjects and found to be cosmetically appealing. In this study, the new whitening formula containing ferulic acid, Ginkgo Biloba, lipohydroxyacid (LHA), niacinamide and thermal spring water was safe and significantly improved chloasma after a 3-month-treatment period compared with placebo. 展开更多
关键词 CHLOASMA MELASMA Hemi-MASI Skin-whitening Ferulic Acid GINKGO Biloba LHA NIACINAMIDE Thermal Spring Water
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Application of pre-whitened-constrained-MUSIC in ship-borne radar 被引量:1
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作者 ZhangZhong SunXiaojun YuanYeshu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第2期147-152,共6页
In ship-borne radar, because of the influence of interference factors such as the correlation of background array noise and the coherence of targets and so on, the performance of high-resolution algorithms such as MUS... In ship-borne radar, because of the influence of interference factors such as the correlation of background array noise and the coherence of targets and so on, the performance of high-resolution algorithms such as MUSIC is degraded. In this document by pre-whitening of background array color noise, de-correlation of coherent targets, compensation of amplitude-phase mismatch, pre-whitened-constrained-MUSIC algorithm in ship-borne radar effectively resolutes ship target and first-order sea echo. Furthermore, the algorithm performance is compared with other algorithms, result shows that pre-whitened-constrained-MUSIC can be applied effectively in high-resolution processing in ship-borne radar. 展开更多
关键词 ship-borne radar pre-whitened-constrained-MUSIC algorithm sea clutter.
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In Vivo Study of a Natural Whitening Agent 被引量:1
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作者 Li Lingyu Zhu Le +5 位作者 Chen Mo Zhao Ya Zhou Ying Yuan Dengfeng Ni Xiangmei Jia Haidong 《China Detergent & Cosmetics》 CAS 2023年第4期55-58,共4页
A natural whitening agent to replace synthetic bioactives was developed.Xin Qi Bai(XQB)was composed of traditional Chinese medicine(TCM)and the whitening efficacy was tested in vivo.Qualified volunteers were selected ... A natural whitening agent to replace synthetic bioactives was developed.Xin Qi Bai(XQB)was composed of traditional Chinese medicine(TCM)and the whitening efficacy was tested in vivo.Qualified volunteers were selected and used cream with or without XQB for 8 weeks continuously.The individual type angle(ITA°),melanin index(MI)and the stain area(%)were tested after 0,2,4 and 8 weeks.XQB can increase ITA°value,decrease MI value and the stain area of skin.Results showed that XQB has good whitening efficacy in vivo,and is a natural whitening agent. 展开更多
关键词 whitenING in vivo traditional Chinese medicine
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Whitening Effect for Wool Processed by Rare Earth in the Dyeing Processes
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作者 王夺元 容建明 +3 位作者 何慧珠 张振宗 寿涵森 叶建平 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第4期306-308,共3页
The wool which were processed by rare earth in the dyeing processes have soft and loose hair withpure-white tone and silky luster. A few papers concerned with the mechanism of wool dyeing in the presenceof rare earth~... The wool which were processed by rare earth in the dyeing processes have soft and loose hair withpure-white tone and silky luster. A few papers concerned with the mechanism of wool dyeing in the presenceof rare earth~[1,2]. However, the distribution of the combining of rare earth ions with wool toward the color andluster of woollen has not been discussed yet. In this paper, the whitening effect of Inner Mongolia goatwoolprocessed by rare earth after coarse wool were pulled out was investigated by electronic spectral ana-lysis. The wool samples including normal and rare earth processed Inner Mongolia goat wool were supplied 展开更多
关键词 whitening effect WOOL Rare earth
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Mechanism of Wool Whitening in the Rare Earth Assistant Dyeing Process
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作者 王夺元 容建明 何慧珠 《Journal of Rare Earths》 SCIE EI CAS CSCD 1992年第3期223-226,共4页
The keratins of wool underwent Photooxidation to form a weaker luminophor in visible blue region (λ_(max)=420nm),that reacts with cerium ion to produce an enhanced luminophor complex (λ_(max)=426 nm),it makes wool w... The keratins of wool underwent Photooxidation to form a weaker luminophor in visible blue region (λ_(max)=420nm),that reacts with cerium ion to produce an enhanced luminophor complex (λ_(max)=426 nm),it makes wool white obviously. 展开更多
关键词 Rare earth Assistant dyeing whitening wool
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Chemical analysis of hydroquinone and retinoic acid contents in facial whitening creams
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作者 Aung Myo Htet Ei Ei Thin +1 位作者 Mi Mi Saw Soe Win 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第1期89-90,共2页
Hydroquinone is potentially carcinogenic and is known to be a skin and respiratory irritant.Hydroquinone is carcinogenic it has been banned in some countries because of fears of a cancer risk[1,2].Animal studies have ... Hydroquinone is potentially carcinogenic and is known to be a skin and respiratory irritant.Hydroquinone is carcinogenic it has been banned in some countries because of fears of a cancer risk[1,2].Animal studies have shown that topically applied retinoic acid can be photocarcinogenic[3].The aim of this study was qualitative and quantitative determination of hydroquinone and retinoic acid contents in facial whitening creams by colour reaction tests,FT-IR after TLC separation and HPLC. 展开更多
关键词 HYDROQUINONE and RETINOIC ACID HPLC FACIAL whitenING creams
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Development of Tea Whitener Using Concentrated Whey and Milk Solids
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作者 Jyothis Joy Mazhuvanchery Satish Kulkarni 《Food and Nutrition Sciences》 2013年第2期215-221,共7页
Whey and toned milk was effectively used for the development of tea whitener. Cheese whey was concentrated to 12% solids in a vacuum evaporator, pasteurized at 72℃±2℃ for 15 s, diluted back to 11.5% solids and ... Whey and toned milk was effectively used for the development of tea whitener. Cheese whey was concentrated to 12% solids in a vacuum evaporator, pasteurized at 72℃±2℃ for 15 s, diluted back to 11.5% solids and was cold blended with toned milk of 11.5% solids in three ratios viz. 25:75, 50:50 and 75:25 and selected blends were homogenized at 1200-1500 psi. Tea was prepared by adding 80 mL whitener to 100 mL decoction and addition of sugar at 8% (w/v). The tea whitener was selected based on the sensory attributes of tea beverages. The colour of the beverages, tea whiteners and decoction were analyzed by reflectance meter and computer vision image analysis technique. The viscosity of the beverage was tested using a Brookfield viscometer. Coffee stability test was done to assess the stability of tea whitener under acidic conditions. Standard plate count, Coliform count and Presumptive Coliform test were done to assess the microbiological quality of the whitener. Homogenization had a positive impact on the viscosity and colour. The reflectance value of tea prepared from 25% homogenised whey milk blend and toned milk were in the range of 43-46 and 45-49, respectively. The viscosity of tea was found to increase with homogenization and whey levels. The sedimentation values of 25% whey blends and toned milk were 1.25 mL and 1 mL respectively. The shelf life of the blends was 2 days under refrigerated conditions. It can be concluded that a satisfactory tea whitener can be prepared by blending whey with toned milk in 25:75 proportion followed by homogenization. 展开更多
关键词 Concentrated WHEY HOMOGENIZATION SENSORY Evaluation Toned MILK TEA TEA whitener
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Entire Whitening of Apple Trees to Increase Chill Units in Regions of Warm Temperatures during the Fall-Winter Seasons
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作者 Alejandro Zermeño-González J. A. Gil-Marín +2 位作者 H. Ramírez-Rodríguez A. I. Melendres-Alvarez M. Cadena-Zapata 《American Journal of Plant Sciences》 CAS 2022年第8期1100-1115,共16页
Different studies have shown that global warming and climate change have increased the planet’s temperature in different locations. For the apple-growing farmers, this may have a negative impact on the accumulations ... Different studies have shown that global warming and climate change have increased the planet’s temperature in different locations. For the apple-growing farmers, this may have a negative impact on the accumulations of chill units when the air temperature during the fall-winter season increases. When the entire trees are covered with a reflective material, the wood temperature may decrease. Therefore, the objective of this study was to evaluate the effect of whitening (with calcium hydroxide) the entire apple trees (Malus domestica Borkh) after defoliation, on the branches and trunks’ internal temperature (under the bark), the accumulation of chill units (CU), its effects on fruit yield and quality and the relation with the use of thidiazuron (TDZ) (inducer of budbreak). The study was conducted during the fall-winter seasons of 2019-2020 and 2020-2021. The results of this study showed that at the hours of the highest incidence of solar radiation, the internal temperature of the whitened trunks and leaves decreases up to 9&deg;C and 6&deg;C respectively. The accumulated CU during the time of the study, of the whitened branches were up to 81% higher than the ones recorded on the branches with no whitening;while the CU was lost at the hours of highest solar radiation (due to a high temperature) were up to 37.2% smaller. Entire tree whitening increased up to 26% of the yield per tree compared to the application of TDZ. No statistical difference in fruit quality was observed between whitened trees and those with no whitening but with the application of thidiazuron. 展开更多
关键词 Malus domestica Borkh Chill Units whitenING Calcium Hydroxide BUDBREAK
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Walnut Meal Whitening and the Impact of Whitening Factors on Its Quality
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作者 Grosu Carolina Siminiuc Rodica +2 位作者 Dinu Turcanu Covaliov Eugenia Gutium Olga 《Food and Nutrition Sciences》 2021年第1期1-12,共12页
Walnut meal is a nutrient-rich product and has a high nutritional value. Walnut meal is a product that can be used in food technology, in order to improve the nutritional quality, expand the range of confectionery pro... Walnut meal is a nutrient-rich product and has a high nutritional value. Walnut meal is a product that can be used in food technology, in order to improve the nutritional quality, expand the range of confectionery products, and replace<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> the walnut kernel. Due to the dark color, the use of the walnut meal in the preparation of pastries would have a negative effect on the appearance of some final products and the whitening process would allow its use without negatively influencing the final product. The aim of the research is to whiten </span><i><span style="font-family:Verdana;">Juglans regial L.</span></i><span style="font-family:Verdana;"> walnut meal as a valuable nutritious raw material. Hydrogen peroxide was used to bleach the walnut meal, and the pH, concentration of the whitening agent and the concentration of the meal were used as variable parameters of the bleaching process. The color descriptors (Whitening index, Saturation index, Total color difference, Browning index) were calculated to establish the optimal whitening conditions of the walnut meal. The obtained results showed that an alkaline medium, with the hydrogen peroxide concentration of 10% and 2.5% meal concentration allow</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span><span><span><span> obtaining the best color parameters in terms of Lightness (82.20) and Whitening Index (71.20). In addition, the study of walnut meal quality in terms of peroxide value evolution showed that the treatment with hydrogen peroxide does not affect in any way the value of the peroxide index of the lipids. The highest peroxide value (4.91 mmol/g oil) was recorded for the sample bleached in a 10% Hydrogen peroxide solution, with a pH of 10 against the 4.71 mmol/g oil for the unbleached sample.</span></span></span> 展开更多
关键词 Walnut Meal whitenING Color Parameters
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Extraction and Refining Process of Polysaccharide from Tricholoma matsutake and Verification of Its Whitening Effect
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作者 Quan AN Guoqing LI +2 位作者 Xuetao LI Ruijun JU Xue SHAO 《Medicinal Plant》 CAS 2023年第1期19-24,共6页
[Objectives]The paper was to determine the extraction and refining process of polysaccharide from Tricholoma matsutake,and to verify its whitening effect.[Methods]With T.matsutake as the research object,the effects of... [Objectives]The paper was to determine the extraction and refining process of polysaccharide from Tricholoma matsutake,and to verify its whitening effect.[Methods]With T.matsutake as the research object,the effects of eluent concentration,loading amount and diameter-to-height ratio on the refining process of T.matsutake polysaccharide were explored by orthogonal test,to optimize the dynamic elution conditions of T.matsutake polysaccharide.The survival rate of mouse melanoma cells(B16),inhibition of melanin synthesis and inhibition of tyrosinase activity of crude extract A1 and refined extracts A2-A4 were tested to verify the whitening effect of T.matsutake.[Results]The best extraction and refining process for T.matsutake polysaccharide was:eluent 40%ethanol(volume fraction),loading amount 30 mg/g(polysaccharide-resin),diameter-to-height ratio 1∶8.Under this condition,the extraction rate of T.matsutake can reach up to 33%(A3).The whitening efficacy test showed that crude extract A1 and refined extracts A2-A4 had good whitening effects,and the whitening effects were A3≥A4>A1>A2.[Conclusions]The study provides a reference for the application of T.matsutake polysaccharide in cosmetics. 展开更多
关键词 Tricholoma matsutake POLYSACCHARIDE EXTRACTION PURIFICATION whitenING
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Spectrofluorometric Study of the Inclusion Complexation of Fluorescent Whitening Agents and β-Cyclodextrins
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作者 Carlos Alberto Ramírez Barragán Ezequiel Delgado Fornué +2 位作者 Jesús Angel Andrade Ortega Guillermo Toríz González Héctor Jesús Contreras Quiñones 《International Journal of Organic Chemistry》 CAS 2016年第4期192-206,共15页
The inclusion complexation behavior of 2,5-Bis(5-tert-butyl-benzoxazol-2yl)-thiophene (UVOB) with native β-cyclodextrin (βCD) and βCD-monochlorotriazinyl (βCD-MCT) was evaluated by fluorescence spectroscopy. The a... The inclusion complexation behavior of 2,5-Bis(5-tert-butyl-benzoxazol-2yl)-thiophene (UVOB) with native β-cyclodextrin (βCD) and βCD-monochlorotriazinyl (βCD-MCT) was evaluated by fluorescence spectroscopy. The association constant (K<sub>s</sub>), stoichiometry, , and were evaluated at 25℃ ± 0.1℃ in phosphate buffer solution (pH = 10.5, 0.1 mo&bull;dm<sup>–3</sup>) in order to find out the complex formation ability and stability. Fluorescence enhancement for UVOB and UVBNB with both CDs has been observed as a result of the complex formation. A stoichiometry 1:1 for UVOB in both CDs was observed;a stoichiometry 3:1 for UVBNB in both CDs has been observed. The K<sub>s</sub>values for UVOB were 4916 ± 137 M<sup>–1</sup> and 655 ± 19 M<sup>–1</sup> (acetone: water 90/10, v/v) with βCD and βCD-MCT, respectively. The value obtained indicates a spontaneous and stable complex formation, but the complex βCD-UVOB showed high K<sub>s </sub>value as an indicative of a high concentration of complex formed. Additionally, K<sub>s </sub>and thermodynamic parameters and were evaluated in a commercial product UVBNB (UVOB, 13%, v/v). In aqueous solution, the values obtained were 2552 ± 115 and 1787 ± 75 M<sup>–1</sup> respectively. Complexation of UVOB with CDs is an interesting approach for utilization of UVOB in aqueous systems without the need of solvents and or surfactants used in commercial product (UVBNB). 展开更多
关键词 SPECTROFLUOROMETRY β-Cyclodextrin Monochlorotriazinyl Fluorescent whitening Agents Inclusion Complexation
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Qualitative and Quantitative Estimation of Hydroquinone in Skin Whitening Cosmetics
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作者 Saima Siddique Zahida Parveen +1 位作者 Zeeshan Ali Muhammad Zaheer 《Journal of Cosmetics, Dermatological Sciences and Applications》 2012年第3期224-228,共5页
Hydroquinone has been used for decades as a skin lightening agent. Its use in cosmetics has been banned as a result of skin problems including contact dermatitis and ochronosis. A total of 22 samples of different skin... Hydroquinone has been used for decades as a skin lightening agent. Its use in cosmetics has been banned as a result of skin problems including contact dermatitis and ochronosis. A total of 22 samples of different skin whitening cosmetics were collected from local market. They were analyzed by using thin layer chromatography and HPLC for qualitative and quantitative determination of their hydroquinone contents. The hydroquinone was extracted from samples by using 96% ethanol and was subjected to TLC analysis. Eleven out of 22 samples were found to contain hydroquinone. The HPLC analysis showed the concentration of hydroquinone ranged from 0.002% to 0.092% in the cosmetic samples. 展开更多
关键词 HYDROQUINONE HPLC whitenING COSMETICS THIN Layer CHROMATOGRAPHY
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Study on The Whitening Effect of a Composite Plant Extract
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作者 Zhang Hao Tang Wendi +3 位作者 Hu Qiuming Zhong Meiying Li Yan Wang Yan 《China Detergent & Cosmetics》 CAS 2023年第3期51-57,共7页
By compounding the cranberry extract,lavender flower extract,Kakadu plum extract,edelweiss flower/leaf extract and aloe vera extract into a composite plant extract(BIRC-Rosée WT100),the whitening effects of this ... By compounding the cranberry extract,lavender flower extract,Kakadu plum extract,edelweiss flower/leaf extract and aloe vera extract into a composite plant extract(BIRC-Rosée WT100),the whitening effects of this composite plant extract in antioxidation,anti-inflammation,skin barrier maintenance,and inhibition of melanin production and transport were evaluated.By comparing the inhibitory effects on tyrosinase activity between the composite plant extract andα-arbutin,and then analyzing the decline of apparent chromaticity,apparent brightness and melanin content through 3D melanin skin model platform,the comprehensive whitening effect was evaluated and compared with that of kojic acid.The results showed that,the composite plant extract(BIRC-Rosée WT100)had a tyrosinase inhibition rate of 98.99%at the original concentration,which was much higher than that ofα-arbutin.In 3D melanin skin model,the apparent chromaticity and brightness could be effectively improved,and moreover,the total amount of melanin in the skin could be reduced,showing remarkable whitening effect. 展开更多
关键词 whitening effect composite plant extract skin barrier bilberry fruit extract 3D melanin skin model
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