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超声辅助核桃蛋白提取和酶解及超声作用影响研究

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超声辅助核桃蛋白提取和酶解及超声作用影响研究

作者： raya ma.oud sehemu 江苏大学

学位级别：硕士

核桃粕是核桃经过挤压出油后的副产品,数量巨大,大多数核桃粕都被用来喂养动物或被直接丢弃。核桃粕是蛋白质的良好来源,然而,目前对核桃蛋白的研究主要集中在碱法提取核桃蛋白上。这种传统方法不仅费时低效,而且加工工艺也不适应于未... 详细信息

核桃粕是核桃经过挤压出油后的副产品,数量巨大,大多数核桃粕都被用来喂养动物或被直接丢弃。核桃粕是蛋白质的良好来源,然而,目前对核桃蛋白的研究主要集中在碱法提取核桃蛋白上。这种传统方法不仅费时低效,而且加工工艺也不适应于未来工业的发展。因此,研究一种有效的制备方法来克服这些缺点意义重大。本研究的目的是:(1)优化扫频超声辅助碱提核桃蛋白技术,同时与传统碱提技术相对比,评价超声处理对核桃蛋白性能的影响;(2)建立扫频超声辅助碱提核桃蛋白的动力学模型,同时考察超声的影响;(3)优化超声辅助核桃蛋白酶解技术,并与传统酶解技术比较,评价超声处理对核桃多肽性能的影响。主要结论如下:(1)扫频超声辅助碱提核桃蛋白的研究结果表明,研究的所有超声因素对核桃蛋白的产量和含量均有显著影响。获得了核桃蛋白的最佳超声辅助碱液提取工艺参数为:料液比1:12、p H值9.0、初始温度15℃、频率28 k Hz、扫频振幅1.5 k Hz、扫频周期100 ms、占空比77%(10s/3s)、处理时间90 min,在此条件下,核桃蛋白得率和含量分别为14.7%和34.7%。与传统碱提相比(10.9%和31.6%),蛋白得率和含量分别增加了34.9%和9.8%。由此得出超声处理显著提高了核桃蛋白的得率和含量。傅里叶红外光谱、荧光光谱、圆二色谱和扫描电镜结果表明,超声处理提高了蛋白质间的氢键作用力和环状酰胺的形成,破坏了核桃蛋白的三级结构,并使二级结构趋于有序,微观结构更加分散,这有利于提高超声提取的核桃蛋白的热稳定性。(2)扫频超声辅助碱提取动力学的研究结果表明,超声功率强度(UPI)和超声温度对可溶性蛋白的浓度和溶出率均有正向影响,两者具有协同作用,超声显著提高了核桃粕中核桃蛋白的提取率。在不考虑蛋白聚集影响的情况下,得到真实的动力学模型为:0.015 2.801 0.957 2.702 0.957 2.702y(28)8.588E-6×P T[1-exp(-7.896E-15P T×t)](10)0.1909 exp(-7.896E-15×P T×t)在该模型中,可溶性蛋白溶出率y∞的数值大小与超声功率强度、超声温度和超声时间有关。傅里叶红外光谱结果表明在较短的超声处理时间内,超声处理使蛋白质中C=O基团与附近基团结合形成了环状酰胺。荧光结果表明,超声波干扰了核桃蛋白的三级结构。圆二色谱结果表明,超声处理后核桃蛋白质的二级结构发生了显著变化,变得更加有序。SEM结果表明,超声波使得可溶性蛋白和提取后残渣的微观结构发生了明显的变化,变得更加分散。(3)超声工作模式筛选试验结果表明,较平板式超声(A、B、C、D和E)而言,探头式超声(F、G和H组)可显著提高核桃多肽的活性。其中,20/40 k Hz(H组)探头式超声模式下的ACE抑制率最高。因此,超声辅助核桃蛋白酶解制备核桃多肽的最佳条件为:底物浓度20 g/L、加酶量16500 U/g、酶解温度50℃、p H值9.0、超声功率强度100 W/L、频率组合20/40 k Hz、超声占空比10s/5s、超声工作时间30 min、剩余酶解时间120 min。在此条件下,DH和ACE抑制率分别为24.5%和59.3%。与传统酶解相比,超声处理后多肽的ACE抑制率显著提高,提高率达23.8%。在酶解过程中,超声处理使得多肽的分子量分布更集中在200-1000 Da,且分子量在200-1000 Da的多肽含量显著增加了30.3%。此外,超声处理后,多肽液中疏水性氨基酸含量显著提高,提高率高达4.0%。分子量在200-1000 Da的多肽含量和多肽中疏水性氨基酸含量的增加都有利于高活性肽组分的产生,这可以很好地解释超声处理使得多肽的ACE抑制率提高的原因。

关键词：核桃粕蛋白碱液提取超声波动力学酶解 ACE抑制肽

A Multilevel Method for the Solution of Time Dependent Optimal Transport

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Numerical mathematics(Theory,Methods and Applications) 2015年第1期8卷 97-111页

作者： Eldad Haber raya Horesh Department of mathematics&Department of Earth and Ocean Science The University of British ColumbiaVancouverBCCanada IBM research NYUSA

In this paper we present a new computationally efficientnumerical scheme for the minimizing flow for the computation of the optimal L 2 mass transport map-ping using the fluid *** review the method and discuss its numerical *** then derive a new scaleable,efficient discretization and a solution technique for the problem and show that the problem is equivalent to a mixed form formulation of a nonlinear fluid flow in porous *** demonstrate the effec-tiveness of our approach using a number of numerical experiments.

关键词： Optimal mass transport inverse problems staggered grids

Ecophysiology of egg rejection in hosts of avian brood parasites:new insights and perspectives

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Current Zoology 2021年第6期67卷 631-638页

作者： Francisco RUIZ-raya Centro de Investigación marina Universidade de VigoGEAVigo 36310Spain

Egg rejection is the most effective and widespread defense used by host species to counteract the extreme fitness costs frequently imposed by obligate avian brood ***,the proximate mechanisms underlying between-and within-individual variation in host responses remain poorly *** evidence suggests that egg rejection is dependent on individual physiological states,and draws attention to the role of hormones as mediators of flexible antiparasitic *** this perspective article,I outline recent advances in our understanding of the proximate factors that mediate egg rejection.I also point out some areas where knowledge remains still lacking,especially those related to the development and maintenance of effective cognitive functions,the potential role of oxidative stress,immunological state,and developmental stressors.I propose new hypotheses that stimulate future research on behavioral host responses toward brood parasitism.

关键词： cognitive performance condition-dependence corticosterone flexible responses prolactin

Pion parton distribution function in light-front holographic QCD

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Chinese Physics C 2020年第11期44卷 163-167页

作者： Lei Chang Khépani raya Xiaobin Wang School of Physics Nankai UniversityTianjin 300071China

The valence-quark distribution function of the pion has been of interest for decades;particularly,the profile it should adopt when x→1(the large-x behavior)has been the subject of a long-standing *** the light-front holographic QCD(LFHQCD)approach,this behavior is controlled by the so-called reparametrization function,wτ(x),which is not fully determined from first *** show that,owing to the flexibility of wτ(x),the large-x profile u^π(x)∼(1−x)^2 can be contained within the LFHQCD *** is in contrast to a previous LFHQCD study(Guy *** Teramond et al.,***.,120(18),2018)in which u^π(x)∼(1−x)^1 was found *** our observations,augmented by perturbative QCD and recent lattice QCD results,we state that the large-x exponent of“2”cannot be excluded.

关键词： pion parton distribution function QCD

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Haplotype phasing after joint estimation of recombination and linkage disequilibrium in breeding populations

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Journal of Animal Science and Biotechnology 2014年第1期5卷 38-52页

作者： Luis Gomez-raya Amanda M Hulse David Thain Wendy M Rauw Departamento de Mejora Genética Animal Instituto Nacional deInvestigación y Tecnología Agraria y Alimentaria (INIA) Interdisciplinary Program in Genetics Texas A&M University College Station Department of Animal Biotechnology University of Nevada

A novel method for haplotype phasing in families after joint estimation of recombination fraction and linkage disequilibrium is developed. Results from Monte Carlo computer simulations show that the newly developed E.M. algorithm is accurate if true recombination fraction is 0 even for single families of relatively small sizes. Estimates of recombination fraction and linkage disequilibrium were 0.00 （SD 0.00） and 0.19 （SD 0.03） for simulated recombination fraction and linkage disequilibrium of 0.00 and 0.20, respectively. A genome fragmentation phasing strategy was developed and used for phasing haplotypes in a sire and 36 progeny using the 50 k Illumina BeadChip by： a） estimation of the recombination fraction and LD in consecutive SNPs using family information, b） linkage analyses between fragments, c） phasing of haplotypes in parents and progeny and in following generations. Homozygous SNPs in progeny allowed determination of paternal fragment inheritance, and deduction of SNP sequence information of haplotypes from dams. The strategy also allowed detection of genotyping errors. A total of 613 recombination events were detected after linkage analysis was carried out between fragments. Hot and cold spots were identified at the individual （sire level）. SNPs for which the sire and calf were heterozygotes became informative （over 90%） after the phasing of haplotypes. Average of regions of identity between half-sibs when comparing its maternal inherited haplotypes （with at least 20 SNP） in common was 0.11 with a maximum of 0.29 and a minimum of 0.05. A Monte-Carlo simulation of BTA1 with the same linkage disequilibrium structure and genetic linkage as the cattle family yielded a 99.98 and 99.94% of correct phases for informative SNPs in sire and calves, respectively.

关键词： Breeding Haplotype phasing Linkage disequilibrium SNP

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Córdoba乳腺断层融合筛查试验（CBTST）乳腺筛查间期癌：乳腺断层融合联合数字乳腺摄影与单纯数字乳腺断层成像的比较

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国际医学放射学杂志 2024年第5期 627-628页

作者： C.Pulido Carmona S.Romero martín J.L.raya Povedano M.Cara García P.Font Ugalde E.Elías Cabot 张昕怡

目的比较数字乳腺断层摄影（DBT）+数字乳腺摄影（DM）与单纯DM筛查女性的乳腺筛查间期癌发病率及其特征的差异。方法比较Córdoba乳腺断层融合筛查试验

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Functional explanation of extreme hatching asynchrony: male manipulation Hypothesis

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Zoological Research 2022年第5期43卷 843-850页

作者： manuel Soler Francisco Ruiz-raya Lucia Sanchez-Perez Juan Diego Ibanez-Álamo Juan JoseSoler Departamento de Zoologia Facultad de CienciasUniversidad de GranadaGranada E-18071Spain Unidad Asociada Coevolucion:Cucos Hospedadores y Bacterias SimbiontesUniversidad de GranadaGranada E-18071Spain Centro de Investigacion mariña Universidade de VigoGrupo de Ecoloxia AnimalVigo 36310Spain Departamento de Ecologia Funcional y Evolutiva Estacion Experimental de ZonasÁridas(CSIC)Almeria E-4120Spain

Hatching asynchrony in birds is considered an adaptation to facilitate brood reduction because under conditions of food scarcity, the smallest nestling usually dies soon after hatching, thereby minimizing parental effort. However, in species with extreme hatching asynchrony, the last hatchlings paradoxically experience a very low probability of survival and death can take so long that it can hardly be considered an adaptation. Here, we propose and experimentally tested a new adaptive hypothesis explaining the brood reduction paradox, namely the“male manipulation Hypothesis”. Our hypothesis suggests that by inducing asynchronous hatching,females increase the feeding requirements of the brood, which will induce males to increase provisioning effort. In addition, females may extend the period of male manipulation by feeding the smallest nestling just enough to sustain life. Our study showed that male common blackbirds(Turdus merula) increased their effort(i.e., number of food items per hour) in experimental asynchronous broods compared to synchronous broods, while females reduced their contribution, as predicted by the hypothesis.

关键词： Brood reduction Food allocation Hatchingasynchrony malemanipulation hypothesis Sexual differences in food allocation Turdus merula

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Cognitive style and fostering of technological adaptation drive E-entrepreneurial of new mature business

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International Journal of Innovation Studies 2023年第3期7卷 248-261页

作者： Fadi Abdelfattah Hussam Al Halbusi raya ma.oud Al-Brwani College Of Business Administration(CoBA).A'Sharqiyah University(ASU) IbraOman Modern College of Business and Science MuscatOman management Department Ahmed Bin Mohammed Military CollegeP.O.Box:22988DohaQatar College of Business Administration(CoBA) A'Sharqiyah University(ASU)IbraOman

This study aims to reveal the key drivers that influence young individuals to participate in e-entrepreneurship,an increasingly important aspect of economic growth and *** a survey of 305 Omani entrepreneurs,this research found that entrepreneurship role models,opportunity evaluation decisions,and entrepreneurship education were positively related to the intention to pursue ***,self-perceived creativity was found to significantly enhance the relationships among entrepreneurship role models,entrepreneurship education,and e-entrepreneurship *** results of this study offer valuable insights for policymakers in Oman as they highlight the crucial role that entrepreneurship role models,opportunity evaluation decisions,entrepreneurship education,and self-perceived creativity play in shaping young individuals'attitudes toward *** study makes important theoretical and practical contributions and provides a roadmap for policymakers seeking to promote entrepreneurship and support the growth of new business ventures.

关键词： Entrepreneurship E-Entrepreneurship E-business Innovation Technology 4.0 industry

Influence of self-perceived creativity and social media use in predicting E-entrepreneurial intention

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International Journal of Innovation Studies 2022年第3期6卷 119-127页

作者： Fadi Abdelfattah Hussam Al Halbusi raya ma.oud Al-Brwani Department of management College of Business Administration(COBA)A'Sharqiyah UniversityIbraOman management Department Ahmed Bin Mohammed Military College(ABMMC)P.O.Box:22988DohaQatar

Entrepreneurship has gained widespread attention in the 21st *** study aims to examine the direct effect of self-perceived creativity on e-entrepreneurship intention and the moderating effect of social media use on the relationship between self-perceived creativity and e-entrepreneurship *** were gathered from 248 Omani *** findings revealed that the direct effect of self-perceived creativity and social media use significantly influences e-entrepreneurship ***,the positive impact of self-perceived creativity on e-entrepreneurship intention was moderated by social media *** study concluded that self-perceived creativity is a crucial factor at the start of the entrepreneurial process,as it contributes to designing new products and *** addition,this study introduced social media use as a boundary condition on the relationship between self-perceived creativity and e-entrepreneurial ***,this study differs from other studies,as it examines whether social media improves opportunities for entrepreneurs and works fordiscovering and generating opportunities.

关键词： Self-perceived creativity Social mediause e-entrepreneurship intention e-business