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The effect of caloric restriction on genetical pathways

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Food Science and Human Wellness 2023年第5期12卷 1450-1457页

作者： Mustafa Fevzi Karagöz A.gülçin sa.dıçoğlu Celep Faculty of Health Sciences Department of Nutrition and DieteticsGazi UniversityÇankaya 06490Turkey

Energy restriction is defined as reducing nutrient intake without dragging the organism into malnutrition. Energy restriction is preferred because it is a non-genetic intervention that increases life expectancy. Nicotinamide adenine dinucleotide(NAD~+)and adenosine monophosphate(AMP)levels, which are the indicators of intracellular energy deficiency, increase with energy restriction. The increase in NAD~+ level stimulates sirtuin(SIRT)enzymes, and the increase in AMP level stimulates AMP-activated protein kinase(AMPK). Various mechanisms are regulated by stimulating these enzymes. By Forkhead box O(FoxO)transcription factors, the ability of resistance to oxidative stress increases, and antioxidant genes, DNA repair, and autophagy genes are stimulated. Apoptosis is induced by stimulation of the p53 protein, and tumor growth is suppressed by the disruption of aging cells. The suppression of phosphoinositide 3-kinase(PI3K)-/-Akt, and therefore mTOR signal stimulates autophagy and mitophagia, and cleanses damaged cells and organelles. Mitochondrial biogenesis is stimulated, antioxidant capacity increases, and inflammatory response decreases. Adipose tissue and lipid metabolism are regulated by the regulation of fatty acid synthesis and oxidation. As a consequence, the effects of caloric restriction on cellular metabolism are regulated through the genetic pathways.

关键词： Caloric restriction Energy restriction Sirtuin AMPK Mitochondrial biogenesis

Effects of human disturbance on nest placement of the woodpigeon (Columba palumbus): a case study from the Middle Atlas, Morocco

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Integrative Zoology 2014年第3期9卷 349-359页

作者： sa.d HANANE Forest Research Center High Commissariat for WaterForests and Desertification ControlRabat-AgdalMorocco

The woodpigeon(Columba palumbus)is a common and widespread bird in Morocco(North Africa).I examined,over 2 years(2010 and 2011),the breeding density and nest placement of this game species in relation to nest site habitat and degree of human *** study area was in the Middle Atlas Tighboula mountain forest,Morocco,in a disturbed and an undisturbed *** data collected in the 2 study sites,I aimed to identify the factors influencing the placement of nests within holm oak trees(Quercus rotundifolia)and their densities.I found that habitat structures,influenced by grazing disturbance,have affected nesting density and the location of nests of this *** place their nests in a higher position(3.42±0.19 m)when disturbance intensity is high and lower(1.68±0.1 m)when disturbance intensity is low,and show higher nesting density in less disturbed zone(3.1±0.4 nests/ha)than in highly disturbed zones(1.4±0.2 nests/ha).grazing disturbance could pose a threat to population persistence at a broader scale and could potentially reduce the abundance of this species by altering the composition and the structure of the forest nesting *** multi-scale studies are needed to assess the effects of different levels of grazing disturbance on woodpigeon nest density and placement,and to enhance our knowledge of the breeding behavior of this game species under variable environments.

关键词： breeding density Columba palumbus holm oak Middle Atlas Morocco nest location woodpigeon

C-reactive protein may be a prognostic factor for the whole gastroenteropancreatic neuroendocrine tumor group

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World Journal of gastrointestinal Oncology 2019年第2期11卷 139-152页

作者： ?mer Koma? g?ksel Bengi ?zgül sa.ol Mesut Akarsu Department of Internal Medicine Dokuz Eylul University Faculty of Medicine Department of gastroenterology Dokuz Eylul University Faculty of Medicine Department of Pathology Dokuz Eylul University Faculty of Medicine

BACKgROUND Long non-coding RNAs(lncRNAs) are a kind of single-stranded RNA of more than 200 nucleotides in length and have no protein-coding function. Amounting studies have indicated that lncRNAs could play a vital role in the initiation and development of cancers, including gastric cancer(gC). Considering the crucial functions of lncRNAs, the identification and exploration of novel lncRNAs in gC is *** To identify independent prognostic markers for the whole gastroenteropancreatic neuroendocrine tumor(gEP-NET) *** Ninety-three patients diagnosed with gEP-NETs within a specified period were included in this study. Patient data were retrospectively analyzed. The relationships between all independent variables and 5-year survival status calculated during the follow-up period(months) were assessed. In addition, the relationships between the independent variables were *** When 5-year survival rate was compared, a statistically significant relationship between the age at diagnosis, male gender, tumor size, tumor stage, liver and/or distant metastasis, and tumor grade determined by the Ki-67 level and mitotic count, and the level of C-reactive protein(CRP), was observed. The meansurvival(overall survival) of the study group was 102.5 ± 6.3(SD) mo. The percentages of 1, 3 and 5-year survival were 90%, 72%, and 61%, respectively. In63 of 93 patients, Ki-67 and the mitotic count determined the sa.e grade. The Ki-67 levels in 29 patients and the mitotic count in only 1 patient were in the higher grade. The risk of death increased by 4% for every 1 year increase at the diagnosis age and was 2.0-fold higher for male patients, 3.0-fold higher for g3 according to the mitotic count, 3.7-fold higher for g3 according to the Ki-67 level, 12.7-fold higher for cases with tumor stage 3 or 4 by a 1 cm increase in the ratio of 9% in tumor size, and 6.1-fold higher for patients with liver metastasis for every 1 mg/dL increase in the ratio of 1.5% in CR

关键词： gastroenteropancreatic neuroendocrine tumors C-reactive protein Prognostic factor Neuroendocrine tumors gastrointestinal system

PYRIDINATION OF POLY(VINYL CHLORIDE) via A HOMOLYTIC PATHwaY

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Chinese Journal of Polymer Science 2007年第3期25卷 297-302页

作者： sa.d Moulay Zakia Zeffouni Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Département de Chimie IndustrielleUniversité Sad Dahlab de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

PVC was subjected to a chemical modification aiming at replacing the chlorine atoms by pyridine groups via a homolytic route. Pyridine groups were peculiarly affixed to the PVC matrix via a carbon-carbon bond rather than a carbonnitrogen one. PVC was first iodinated using the Conant-Finkelstein reaction, followed by the application of the homolytic conditions of Minisci to generate pyridinated PVC with a varying degree of substitution. The extent of substitution was not high; the reaction on 30% iodinated PVC afforded a degree of modification no greater than 3%.

关键词： Conditions of Minisci Iodinated PVC Pyridinated PVC

Changes in plant community diversity and aboveground biomass along with altitude within an alpine meadow on the Three-River source region

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Chinese Science Bulletin 2012年第27期57卷 3573-3577页

作者： sa.WenJun AN LiZhe sa.Wei Institute of Botany Science School of Life SciencesLanzhou UniversityLanzhou 730000China School of Life Science Qinghai UniversityXining 810008China

The grassland is an important component of terrestrial ecosystems and plays a significant role in biodiversity and ecosystem *** the present study,the changes of plant species diversity and aboveground biomass productivity were examined along with the altitude in natural alpine grassland in the source region of three rivers on the Qinghai-Tibetan *** experimental locations were selected with altitudes ranging from 3862 to 4450 m above sea level(a.s.l.).The results indicated that Kobresia pygmaea meadow,Kobresia humilis meadow and sa.ix cupularis shrub meadow had higher indices of diversity and aboveground *** distribution of species diversity,richness and aboveground biomass showed similarly unimodal patterns across the altitude gradient with the highest indices appeared at mid-altitudes *** changing trend of species diversity,richness and evenness also showed significant unimodal patterns with total aboveground biomass,and the highest species diversity occurred at intermediate level of *** research would provide a valuable reference for the protection of grassland biodiversity and maintaining of the grazing ecosystem function in the source region of the Three Rivers.

关键词：植物群落多样性地上生物量海拔高度高寒草甸三江源地区植物物种多样性生态系统功能生物多样性

HALOMETHYLATION OF POLYSTYRENE AND SUBSEQUENT PYRIDINATION VIA A HOMOLYTIC PATHwaY

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Chinese Journal of Polymer Science 2006年第6期24卷 627-635页

作者： sa.d Moulay Nadia Mehdi Laboratoire de Chimie-Physique Moléculaire et Macromoléculaire Faculté des Sciences de l'Ingénieur Departement de Chimie IndustrielleUniversité de BlidaRoute de SoumaB. P. 270Blida 09000Algeria

Chloromethylation of polystyrene （PS） with two different chloromethylating systems methylal/thionyl chloride and paraformaldehyde/trimethylchlorosilane was studied. Soluble chloromethylated polystyrene with a degree of substitution of 89% was obtained. The Conant-Finkelstein reaction on the chloromethylated PS afforded soluble iodomethylated polystyrene with a degree of substitution as high as 96%. The reaction conditions of Minisci were employed to radically pyridinate PS via its iodomethylated derivative. Polyelectrolytes were formed which could be converted to normal polymers by treatment with a 20% aqueous solution of NaOH.

关键词： Chloromethylated polystyrene Conditions of Minisci Iodomethylated polystyrene Pyridinated polystyrene.

Response of photosynthesis,growth,and acorn mass of pedunculate oak to diff erent levels of nitrogen in wet and dry growing seasons

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Journal of Forestry Research 2023年第1期34卷 167-176页

作者： Krunoslav Sever sa.a Bogdan ŽeljkoŠkvorc Faculty of Forestry and Wood Technology University of ZagrebSvetošimunska 2510000 ZagrebCroatia

The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levels<2.0%,nitrogen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn mass of ... 详细信息

The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levelsgen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn mass of pedunculate oak during 2010 in the absence of drought stress and during 2011 under the impact of moderate drought *** to the results,moderate drought stress significantly reduced net photo synthetic rate,stem diameter increment and height growth increment,while acorn mass was not *** nitrogen nutrition significantly reduced the net photo synthetic rate and stem diameter increment only in the wet year,acorn mass in both wet and dry years,while height growth increment was not significantly reduced by suboptimal nitrogen nutrition in either *** results indicate that optimal nitrogen levels can stimulate photo synthetic rate and stem diameter increment of pedunculate oak only in the absence of moderate drought ***,the results show that moderate drought stress is a more dominant stressor for photosynthesis and growth of pedunculate oak than suboptimal nitrogen nutrition,while for acorn development,it is the more dominant stressor.

关键词： Quercus robur L. Drought stress Net photosynthic rate Stem diameter increment Height growth increment Acorn mass

一种基于DTW-DP-gMM的工业机器人轨迹学习策略

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天津大学学报（自然科学与工程技术版） 2025年第1期58卷 68-80页

作者：肖洒陈旭阳叶锦华吴海彬福州大学机械工程及自动化学院福州350108 福建省特种智能装备安全与测控重点实验室福州350108

针对机器人示教编程过程中使用高斯混合模型(gMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法... 详细信息

针对机器人示教编程过程中使用高斯混合模型(gMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法.首先,针对示教过程中采集的多条轨迹在时间长度上存在差异的问题,采用DTW算法来统一示教轨迹在时域上的变化.其次,使用gMM算法对示教轨迹的特征进行提取,并利用高斯混合回归(gMR)算法将其重构为复现轨迹.在这个过程中采用DP算法来预估gMM算法的关键参数高斯分布的数量,与传统方法相比,能够简单直观地得到相对准确的参数值.利用DP算法对复现轨迹的数据点进行稀疏化并优化,不仅确保了机器人最终运动轨迹的精度,而且大幅减少了最终轨迹数据点的数量.最后,进行了不同形状的模拟焊接轨迹学习规划实验.结果表明:经由DTW对齐后的示教轨迹具有更加明显的运动特征,经过gMM-gMR学习输出的复现轨迹具有良好的表征结果;在使用gMM-gMR算法学习示教轨迹的过程中,采用DP算法可以有效预估高斯分布个数;经过DP算法稀疏化并优化的最终轨迹的平均位置误差均在0.500 mm以内,其最大误差可以控制在0.800 mm以内,可以满足焊接轨迹规划的精度要求,验证了该策略的有效性和优越性.

关键词：工业机器人示教编程高斯混合模型道格拉斯-普克算法动态时间规整轨迹复现

甘蔗种茎中富集的^15N及贮藏N的再分配与90天龄蔗株对N2的固定

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国外农学（甘蔗） 1990年第2期 19-24页

作者： sa.,EVSB 黄宝孙