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Reverse cholesterol transport: From classical view to new insights

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World Journal of Gastroenterology 2010年第47期16卷 5908-5915页

作者： astrid e van der Velde Academic Medical Center AMC Liver Center Department of education and Development Gelderse Vallei Hospital

Cholesterol is of vital importance for the human body. It is a constituent for most biological membranes, it is needed for the formation of bile salts, and it is the pre- cursor for steroid hormones and vitamin D. However, the presence of excess cholesterol in cells, and in particular in macrophages in the arterial vessel wall, might be harmful. The accumulation of cholesterol in arteries can lead to atherosclerosis, and in turn, to other cardiovascular diseases. The route that is primarily thought to be responsible for the disposal of cholesterol is called reverse cholesterol transport (RCT). Therefore, RCT is seen as an interesting target for the development of drugs aimed at the prevention of atherosclerosis. Research on RCT has taken off in recent years. In this review, the classical concepts about RCT are discussed, together with new insights about this topic.

关键词： Cholesterol excretion Transport Intestine Liver

How Do Sugars Regulate Plant Growth and Development？ New Insight into the Role of Treha Iose-6-Phosphate

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Molecular Plant 2013年第2期6卷 261-274页

作者： Liam e. O'Hara Matthew J. Paul astrid Wingler Genetics Evolution and Environment University College London Gower Street London WCl E 6BT UK Plant Science Rothamsted Research Harpenden Hertfordshire AL5 2JQ UK

Plant growth and development are tightly controlled in response to environmental conditions that influence the availability of photosynthetic carbon in the form of sucrose. Trehalose-6-phosphate （T6P）, the precursor of trehalose in the biosynthetic pathway, is an important signaling metabolite that is involved in the regulation of plant growth and development in response to carbon availability. In addition to the plant＇s own pathway for trehalose synthesis, formation of T6P or trehalose by pathogens can result in the reprogramming of plant metabolism and development. Developmental processes that are regulated by T6P range from embryo development to leaf senescence. Some of these processes are regulated in interaction with phytohormones, such as auxin. A key interacting factor of T6P signaling in response to the environment is the protein kinase sucrose non-fermenting related kinase-1 （SnRK1）, whose catalytic activity is inhibited by T6R SnRK1 is most likely involved in the adjustment of metabolism and growth in response to starvation. The transcription factor bZlP11 has recently been identified as a new player in the T6P/SnRK1 regulatory pathway. By inhibiting SnRK1, T6P promotes biosynthetic reactions. This regulation has important consequences for crop production, for example, in the developing wheat grain and during the growth of potato tubers.

关键词： bZlP11 carbon availability plant development starvation sucrose non-fermenting related kinase-1 (SnRK1) trehalose trehalose-6-phosphate.

Sum of squares methods for minimizing polynomial forms over spheres and hypersurfaces

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Frontiers of Mathematics in China 2012年第2期7卷 321-346页

作者： Jiawang nie Department of Mathematics University of California San DiegoLa Jolla CA 92093 USA

Abstract This paper studies the problem of minimizing a homogeneous polynomial （form） f（x） over the unit sphere Sn-1 = {x ∈ R^n：｜｜X｜｜2 = 1}. The problem is NP-hard when f（x） has degree 3 or higher. Denote by fmin （resp. fmax） the minimum （resp. maximum） value of f（x） on S^n-1. First, when f（x） is an even form of degree 2d, we study the standard sum of squares （SOS） relaxation for finding a lower bound of the minimum .fmin ：max γ s.t.f（x）-γ.｜｜x｜｜2^2d is *** fos be be the above optimal value. Then we show that for all n ≥ 2d,Here, the constant C（d） is independent of n. Second, when f（x） is a multi-form and ^-1 becomes a muilti-unit sphere, we generalize the above SOS relaxation and prove a similar bound. Third, when f（x） is sparse, we prove an improved bound depending on its sparsity pattern; when f（x） is odd, we formulate the problem equivalently as minimizing a certain even form, and prove a similar bound. Last, for minimizing f（x） over a hypersurface H（g） = {x e lRn： g（x） = 1} defined by a positive definite form g（x）, we generalize the above SOS relaxation and prove a similar bound.

关键词： Approximation bound form hypersurface L2-norm G-norm,multi-form polynomial semidefinite programming sum of squ^res

NeCAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno Michael K.e.Schafer Sudena Wang Michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal eF-hand calcium-binding proteins 1–3(NeCAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one eF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NeCAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NeCAB2 interacts with predominantly striatal G-protein-coupled receptors, while NeCAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NeCAB proteins exhibit distinct subcellular localizations: NeCAB1 is found in the nucleus and cytosol, NeCAB2 resides in endosomes and the plasma membrane, and NeCAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NeCAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NeCAB proteins by controlling the availability of protein–protein interaction domains situated between the eF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium eF hand mitochondria nervous system signal transduction

Shear behaviours of cohesionless mixed soils using the DeM:The influence of coarse particle shape

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Particuology 2021年第2期19卷 151-165页

作者： Yangui Zhu Jian Gong Zhihong nie School of Civil engineering Central South UniversityChangsha 410075China

The coarse particles in mixed soils can be cobbles or gravels,with the main difference being their roundness(an indicator describing particle shape characteristics at an intermediate scale).The influence of coarse particle shape(i.e.,roundness)on the macroscopic and microscopic shear behaviours of cohesionless mixed soils with various fines contents(FCs)was investigated via the discrete element method in this *** shapes of coarse particles were formed using the rotation-invariant spherical harmonic method proposed by previous *** equation was proposed to predict the initial void ratios of samples in this study.A decrease in the roundness of coarse particles can increase the peak friction angle(FC≤40%)and critical friction angle(FC≤30%).As the roundness of coarse particles decreases,the peak dilatancy angle initially increases and then decreases(FC≤20%).Furthermore,it was found that the roundness of coarse particles hardly affects the classification of cohesionless mixed soils,as determined by probing the percentage contributions of coarse-coarse,coarse-fine,and fine-fine *** cohesionless mixed soils change from an underfilled structure to an interactive-underfilled structure at the critical state,the main forms of coarse-coarse contacts were ***,the force-fabric anisotropy mechanisms of the influences of the roundness and rolling resistance coefficient of coarse particles on the shear strengths of cohesionless mixed soils were found to be different.

关键词： Cohesionless mixed soils Particle shape Roundness Shear behaviours Discrete element method

Sexual selection and incipient speciation in Hawaiian Drosophila

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Science Bulletin 2016年第2期61卷 125-131页

作者： Haiyan nie Kenneth Kaneshiro Central South University of Forestry and Technology Lab of Insect Systematics and Evolutionary Biology College of Life Science and Technology Pacific Biosciences Research Centre University of Hawaii at Manoa

We conducted sexual selection experiments to produce strains with high and low mating discrimination in females of laboratory strains of Hawaiian Drosophila, ***, then examined secondary sexual traits of these two lines, and compared them with that of standard line. In order to do this, we screened out super-males which mated successfully with females and with high mating records;and poor males which usually could not mate successfully with females and had low mating records. In the meantime,choosy females were also screened out, which almost never responded to males' nuptial dance and were difficult to be mated; but indiscriminate females were on the contrary,which were very ready to accept male's nuptial dance and were very easy to be mated. As a result, by mating supermales with choosy females, we were able to produce the high-line strain; similarly, for the low line, we mated poor males with indiscriminate females and we had a strain that was significantly different from our standard strain within just two generations of selection, i.e., morphological trait differences were measured between the standard strain and the two selected lines, which indicated that mating discrimination has affected secondary sexual traits of the lowline strain significantly: Cilia number on the foretibia of low-line males is significantly different from that of the standard line, which perhaps was the indication of incipient speciation in Hawaiian Drosophila.

关键词： Sexual selection Secondary sexualtrait Incipient speciation Drosophila

electromembrane extraction–Recent trends and where to go

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Journal of Pharmaceutical Analysis 2017年第3期7卷 141-147页

作者： Stig Pedersen-Bjergaard Chuixiu Huang astrid Gjelstad School of Pharmacy University of Oslo Faculty of Health and Medical Sciences School of Pharmaceutical Sciences University of Copenhagen

electromembrane extraction(eMe) is an analytical microextraction technique, where charged analytes(such as drug substances) are extracted from an aqueous sample(such as a biological fluid), through a supported liquid membrane(SLM) comprising a water immiscible organic solvent, and into an aqueous acceptor solution. The driving force for the extraction is an electrical potential(dc) applied across the SLM. In this paper, eMe is reviewed. First, the principle for eMe is explained with focus on extraction of cationic and anionic analytes, and typical performance data are presented. Second, papers published in 2016 are reviewed and discussed with focus on(a) new SLMs,(b) new support materials for the SLM,(c) new sample additives improving extraction,(d) new technical configurations,(e) improved theoretical understanding, and(f) pharmaceutical new applications. Finally, important future research objectives and directions are defined for further development of eMe, with the aim of establishing eMe in the toolbox of future analytical laboratories.

关键词： Sample preparation Microextraction electromembrane extraction

Regular Submanifolds in Conformal Space Q_p^n

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Chinese Annals of Mathematics,Series B 2012年第5期33卷 695-714页

作者： Changxiong nie Chuanxi WU Faculty of Mathematics and Computer Sciences -Hubei University Wuhan 430062 China. E-maih chxnie~*** Institute of Mathematics Sciences Hubei University Wuhan 430062 China. E-maih cxwu@***

The authors study the regular submanifolds in the conformal space Qp^n and introduce the submanifold theory in the conformal space Qp^n. The first variation formula of the Willmore volume functional of pseudo-Riemannian submanifolds in the conformal space Qp^n is given. Finally, the conformal isotropic submanifolds in the conformal space

关键词： Conformal space Conformal invariants Willmore submanifolds Conformal isotropic

Recent Advancements in the Optimization Capacity Configuration and Coordination Operation Strategy of Wind-Solar Hybrid Storage System

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energy engineering 2025年第1期122卷 285-306页

作者： Hongliang Hao Caifeng Wen Feifei Xue HaoQiu Ning Yang Yuwen Zhang Chaoyu Wang edwin e.Nyakilla Department of New energy Storage Peking University Ordos Research Institute of EnergyOrdos017010China School of energy and Power engineering Inner Mongolia University of TechnologyHohhot010080China Key Laboratory of Wind energy and Solar energy Utilization Technology Inner Mongolia University of TechnologyHohhot010051China

Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy *** paper proposes a wind-solar hybrid energy storage system(HeSS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,***/Simulink was used for simulation *** optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 ***,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations *** proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.

关键词： electric-thermal hybrid storage modal decomposition multi-objective genetic algorithm capacity optimization allocation operation strategy