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Acai Fruit as a Source of Bioactive Phytochemicals

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Journal of Life Sciences 2016年第8期10卷 391-404页

作者： Randah m. Alqurashi Daniel m. Commane ian R. Rowland Hugh Sinclair Unit. of Human Nutrition Department of Food and Nutritional Sciences University of Reading Reading RG6 6AP United Kingdom The Saudi Arabian ministry of Education Kingdom of Saudi Arabia

The fruit of the acai palm （Euterpe oleracea mart.） is a rich source of potential bioactive phytochemicals, however neither its precise composition nor the putative benefits to health from its consumption have been fully characterised. This study aims to elucidate the composition of acai fruit pulp and to explore the potential of these extracts to confer protection in a cell culture based model of oxidative DNA damage. Extractions ofcai pulps were dissolved in a 80% methanol （methanol： water, 80：20 v/v） based solvent and the phytochemicals present in the extract were analysing by HPLC detector. Lipids were assessed via GC. The Folin-Ciocalteau assay was used to determine the purposes of providing a phytochemical rich food based comparator with established health benefits. Finally, protection against oxidative DNA damage was assessed in HT-29 cell lines exposed to hydrogen peroxide via the comet assay. Acai pulp extracts were found to be rich in flavonoids, anthocyanins and carotenoids. These extracts were found to protect against oxidative DNA damage （anti-genotoxicity）. A^ai extracts were more effective at preventing oxidative DNA damage than the blueberry extracts, although their antioxidant capacities as assessed by the FRAP assay were similar. These data shown that acai is a rich source of plant phytochemicals and that these chemicals may protect against oxidative stress in human colon cells （HT-29）. Further work is needed to establish the digestive fate of these phytochemicals and to prove the beneficial effects in human.

关键词： Acai pulp antioxidant activity anti-genotoxicity polyphenols.

青海湖裸鲤耳石轮纹O-Sr同位素组成及对其洄游行为的指示

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科学通报 2016年第6期61卷 668-675页

作者：周玲金章东 WILLIAmS ian S 张飞中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710061 西安交通大学全球环境变化研究院西安710049 Research School of Earth Sciences The Australian National UniversityCanberraACT 0200Australia

以溯河洄游为特征的青海湖裸鲤是青海湖鱼类的优势种,但其洄游行为还知之甚少.利用高分辨率SHRImPⅡ离子探针和激光剥蚀高分辨多接收电感耦合等离子体质谱仪(LA-mC-ICP-mS)分别测定了青海湖裸鲤微耳石轮纹中的氧和锶(O-Sr)同位素组成.... 详细信息

以溯河洄游为特征的青海湖裸鲤是青海湖鱼类的优势种,但其洄游行为还知之甚少.利用高分辨率SHRImPⅡ离子探针和激光剥蚀高分辨多接收电感耦合等离子体质谱仪(LA-mC-ICP-mS)分别测定了青海湖裸鲤微耳石轮纹中的氧和锶(O-Sr)同位素组成.结果表明,微耳石成长带中较低的δ^(18)O记录了青海湖裸鲤春夏时期所洄游的河水化学信息;将δ^(18)O与^(87)Sr/^(86)Sr同位素组成相结合,微耳石轮纹的同位素组成明确指示了多数个体可能更倾向于固定的河流洄游产卵.这一结果对于认识青海湖裸鲤的洄游习性以及鱼类保护和管理有重要的意义.

关键词：青海湖裸鲤微耳石轮纹稳定同位素洄游习性

Petroleum geoscience in Norden - exploration, production and organization

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Episodes 2008年第1期31卷 115-124页

作者： Anthony m. Spencer Per Ivar Briskeby Lone Dyrmose Christensen Rune Foyn marie KjФlleberg Erling Kvadsheim ian Knight morten Rye-Larsen John Williams StatoilHydro Forushagen 4035 Stavanger Norway. StatoilHydro 0240 Oslo Norway. StatoilHydro 9481 Harstad Norway. ConocoPhillips P.O. Box 220 4098 Tananger Norway. Norwegian Petroleum Directorate P.O. Box 600 4003 Stavanger Norway. StatoilHydro PO Box 7200 5020 Bergen Norway.

Offshore exploration in Norway and Denmark-in the North Sea, the Norwegian Sea and the Barents Sea-has involved drilling about 850 wildcat wells, resulting in about 300 oil and gas finds, of which 84 are fields with production. The recoverable resources of all these finds total about 65 billion barrels of oil equivalent. Almost all these hydrocarbons come from a Jurassic source and the main reservoirs and traps are Jurassic sandstones in fault blocks and Paleocene sandstones or Cretaceous chalks in gentle domes. The article describes four major fields-Ekofisk, Gullfaks, Ormen Lange and SnФhvitto illustrate some of the many challenges in developing and producing the hydrocarbons. Elsewhere in Norden, there has been much less exploration. Drilling results have mostly been negative in mainland Sweden, onshore Denmark, onshore Svalbard and on- and offshore West Greenland. minor oil finds have been made in Palaeozoic rocks in the Baltic Sea. The first wells have recently been drilled off the Faroe Islands, resulting in one discovery. No drilling has taken place on- or offshore East Greenland. As a result of the hydrocarbon activities in Norway and Denmark, petroleum geoscience there has flourished, with 2000 geoscientists currently employed in the industry, many technical innovations made, a wealth of publically available information and a great increase in the understanding of the geology.

关键词：石油勘探地球科学资源开发地质特征

Hormonal modulation of reproduction and fertility signaling in polistine wasps

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Current Zoology 2021年第5期67卷 519-530页

作者： Cintia Akemi OI Rafael Carvalho DA SILVA ian STEVENS Helena mendes FERREIRA Fabio Santos NASCImENTO Tom WENSELEERS Laboratory of Socioecology and Social Evolution KU LeuvenLeuven 3000Belgium Faculdade de Filosofia Ciencias e Letras de Ribeirao PretoDepartamento de BiologiaUniversidade de Sao Paulo—USPRibeirao PretoSP 14040-901Brazil

In social insects,it has been suggested that reproduction and the production of particular fertilitylinked cuticular hydrocarbons(CHC)may be under shared juvenile hormone(JH)control,and this could have been key in predisposing such cues to later evolve into full-fledged queen pheromone ***,to date,only few studies have experimentally tested this“hormonal pleiotropy”***,we formally test this hypothesis using data from four species of Polistine wasps,Polistes dominula,Polistes satan,mischocyttarus metathoracicus,and mischocyttarus cassununga,and experimental treatments with JH using the JH analogue methoprene and the anti-JH *** line with reproduction being under JH control,our results show that across these four species,precocene significantly decreased ovary development when compared with both the acetone solvent-only control and the methoprene *** with the hormonal pleiotropy hypothesis,these effects on reproduction were further matched by subtle shifts in the CHC profiles,with univariate analyses showing that in *** and *** the abundance of particular linear alkanes and mono-methylated alkanes were affected by ovary development and our hormonal *** results indicate that in primitively eusocial wasps,and particularly in Polistes,reproduction and the production of some CHC cues are under joint JH *** suggest that pleiotropic links between reproduction and the production of such hydrocarbon cues have been key enablers for the origin of true fertility and queen signals in more derived,advanced eusocial insects.

关键词： Polistinae wasps fertility cues queen pheromones cuticular hydrocarbons juvenile hormone

山西省早白垩纪碳酸岩元素同位素和锆石U-Pb定年研究(英文)

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岩石学报 2014年第2期30卷 350-360页

作者：刘燊冯彩霞胡瑞忠赖绍聪 ian m Coulson 冯光英杨毓红大陆动力学国家重点实验室西北大学地质学系西安710069 矿床地球化学国家重点实验室中国科学院地球化学研究所贵阳550002 国体地球研究实验室里贾纳大学地质学系

碳酸岩广泛出露在华北克拉通的山西省。此文中,针对研究区的碳酸岩墙,我们给出新的地球化学、Sr-Nd同位素和锆石U-Pb年龄。LA-ICP-mS锆石定年结果显示,该岩墙的侵位年龄为132.9ma,全岩K-Ar年龄为131.3~132.6 ma。碳酸岩墙具有非常一致... 详细信息

碳酸岩广泛出露在华北克拉通的山西省。此文中,针对研究区的碳酸岩墙,我们给出新的地球化学、Sr-Nd同位素和锆石U-Pb年龄。LA-ICP-mS锆石定年结果显示,该岩墙的侵位年龄为132.9ma,全岩K-Ar年龄为131.3~132.6 ma。碳酸岩墙具有非常一致的主量元素组成,富集轻稀土元素和大离子亲石元素(Ba、U、Pb、Sr),以及亏损K和高场强元素(Ta、P和Ti)。另外,该岩墙具有相对一致的(87Sr/86Sr)i(0.7079~0.7083)和负的εNd(t)(-16.7^-15.2)。以上地球化学特征表明,该岩墙为大陆地壳和此大陆岩石圈地幔混合时期,受明显地壳混染的下岩石圈地幔的部分熔融作用。

关键词：白垩纪碳酸岩墙山西华北克拉通北部

Developing Wheat for Improved Yield and Adaptation Under a Changing Climate： Optimization of a Few Key Genes

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Engineering 2018年第4期4卷 514-522页

作者： m.A.N. Nazim Ud Dowl ian Edwards Graham O'Hara Shahidul Islam Wujun ma School of Veterinary and Life Sciences Murdoch University Perth WA 6150 Australia Edstar Genetics Pry. Ltd. Perth WA 6150 Australia

Wheat grown under rain-fed conditions is often affected by drought worldwide. Future projections from a climate simulation model predict that the combined effects of increasing temperature and changing rainfall patterns will aggravate this drought scenario and may significantly reduce wheat yields unless appropriate varieties are adopted. Wheat is adapted to a wide range of environments due to the diversity in its phenology genes. Wheat phenology offers the opportunity to fight against drought by modifying crop developmental phases according to water availability in target environments. This review summa- rizes recent advances in wheat phenology research, including vernalization （Vrn）, photoperiod （Ppd）, and also dwarfing （Rht） genes. The alleles, haplotypes, and copy number variation identified for Vrn and Ppd genes respond differently in different climatic conditions, and thus could alter not only the development phases but also the yield. Compared with the model plant Arabidopsis, more phenology genes have not yet been identified in wheat; quantifying their effects in target environments would benefit the breeding of wheat for improved drought tolerance. Hence, there is scope to maximize yields in water-limited envi-ronments by deploying appropriate phenology gene combinations along with Rht genes and other important physiological traits that are associated with drought resistance.

关键词： Phenology Wheat Vernalization Photoperiod Drought Climate change

Altitudinal migration behavior patterns of birds on the eastern slope of ***,China

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Avian Research 2023年第3期14卷 385-393页

作者： ian Haase Zhengwei Liu Shangmingyu Zhang Zhehan Dong Yuwen Cheng Kaize Feng Kexin Peng Jianghong Ran Yongjie Wu Key Laboratory of Bio-Resources and Eco-Environment Ministry of EducationCollege of Life SciencesSichuan UniversityChengdu610065China

many bird species in montane regions exhibit altitudinal migration behavior;however,altitudinal migration of birds is still understudied,especially in ***(7556 m) is the highest peak of the Hengduan mountains in Southwest *** steep elevation gradient and the high bird diversity make the eastern slope of ***(Hailuo Valley) an ideal place for studying the altitudinal migration behavior patterns of *** synchronously recorded the local bird diversity,temperature and humidity at two sites(1800 and 3000 m a.s.l.) during three migration seasons from September 2020 to June 2021 to identify birds exhibiting altitudinal migration *** our surveys,we recorded 146 bird species in total and 20 passerine bird species were altitudinal migrants according to our altitudinal migration *** those 20 altitudinal migrant species,eight bird species displayed a typical altitudinal migration pattern(upward migration during the breeding season and downward migration during the non-breeding season).moreover,temperature was correlated with the daily number of individuals(DNI) at each study ***,increasing temperatures possibly caused upward migration of birds(DNI decreased at 1800 m and increased at 3000 m) and vice *** further elaborate,the Rufousgorgeted Flycatcher(Ficedula strophiata),the species with the most prominent altitudinal migration behavior,initiated upward migration at a temperature of 11-12℃ at 1800 m and initiated downward migration at a temperature of 12-13℃ at 3000 ***,humidity was positively correlated with the ***,increasing humidity(equals to increasing rainfall or snow) possibly caused downward migration of birds(DNI increased) and vice ***,bird species exhibiting a typical altitudinal migration behavior pattern are feeding on ***,the spatial and temporal changes of the invertebrate biomass might be an important ecological driver for the altitudinal migration of invertiv

关键词： Altitudinal migration Birds Hengduan mountains Humidity Invertebrate biomass mt.Gongga Temperature

Ammonia-oxidizing archaea and bacteria are structured by geography in biological soil crusts across North American arid lands

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Ecological Processes 2013年第1期2卷 98-107页

作者： Yevgeniy marusenko Scott T Bates ian Anderson Shannon L Johnson Tanya Soule Ferran Garcia-Pichel School of Life Sciences Arizona State UniversityP.O.Box 874501TempeAZ 85287-4501USA Cooperative Institute for Researchin Environmental Sciences University of ColoradoBoulderCO80309USA Bioscience Division B-11Los Alamos National LaboratoryLos AlamosNM87545USA Department of Biology Indiana University-Purdue UniversityFort WayneINUSA

Introduction:Biological soil crusts(BSCs)can dominate surface cover in dry lands worldwide,playing an integral role in arid land biogeochemistry,particularly in N fertilization through fixation and *** is a characteristic and universal N transformation in BSCs that becomes important for the export of N beyond the microscopic bounds of the crust *** contribution of ammonia-oxidizing bacteria(AOB)in BSCs has been shown,but the role and extent of the recently discovered ammonia-oxidizing archaea(AOA)have ***:We sampled various types of crusts in four desert regions across the western United States and characterized the composition and size of ammonia-oxidizing communities using clone libraries and quantitative PCR targeting the amoA gene,which codes for the ammonia monooxygenase enzyme,universally present in ammonia-oxidizing ***:All archaeal amoA sequences retrieved from BSCs belonged to the Thaumarchaeota(Nitrososphaera associated Group I.1b).Sequences from the Sonoran Desert,Colorado Plateau,and Great Basin were indistinguishable from each other but distinct from those of the Chihuahuan *** on amoA gene abundances,archaeal and bacterial ammonia oxidizers were ubiquitous in our survey,but the ratios of archaeal to bacterial ammonia oxidizers shifted from bacterially dominated in northern,cooler deserts to archaeally dominated in southern,warmer ***:Archaea are shown to be potentially important biogeochemical agents of biological soil crust N *** associated with different types of BSCs and biogeographical factors reveal a niche differentiation between AOA and AOB,possibly driven by temperature.

关键词： Biological soil crust Desert Arid amoA Ammonia oxidation Nitrification Nitrogen cycle Thaumarchaeota

Bone Regeneration Based on Tissue Engineering Conceptions – A 21st Century Perspective

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Bone Research 2013年第3期1卷 216-248页

作者： Jan Henkel maria A.Woodruff Devakara R.Epari Roland Steck Vaida Glatt ian C.Dickinson Peter F.m.Choong michael A.Schuetz Dietmar W.Hutmacher Institute of Health & Biomedical Innovation Queensland University of TechnologyBrisbane Queensland Australia Orthopaedic Oncology Service Princess Alexandra HospitalBrisbane Australia Department of Surgery University of Melbourne St. Vincent's HospitalMelbourne Australia Department of Orthopaedics St. Vincent's HospitalMelbourneAustralia Bone and Soft Tissue Sarcoma Service Peter MacCallum Cancer CentreMelbourne Australia Orthopaedic and Trauma Services Princess Alexandra HospitalBrisbane Australia George W Woodruff School of mechanical Engineering Georgia Institute of TechnologyAtlanta GA USA

The role of Bone Tissue Engineering in the field of Regenerative medicine has been the topic of substantial research over the past two decades. Technological advances have improved orthopaedic implants and surgical techniques for bone reconstruction. However, improvements in surgical techniques to reconstruct bone have been limited by the paucity of autologous materials available and donor site morbidity. Recent advances in the development of biomaterials have provided attractive alternatives to bone grafting expanding the surgical options for restoring the form and function of injured bone. Specifically, novel bioactive （second generation） biomaterials have been developed that are characterised by controlled action and reaction to the host tissue environment, whilst exhibiting controlled chemical breakdown and resorption with an ultimate replacement by regenerating tissue. Future generations of biomaterials （third generation） are designed to be not only osteo- conductive but also osteoinductive, i.e. to stimulate regeneration of host tissues by combining tissue engineer- ing and in situ tissue regeneration methods with a focus on novel applications. These techniques will lead to novel possibilities for tissue regeneration and repair. At present, tissue engineered constructs that may find future use as bone grafts for complex skeletal defects, whether from post-traumatic, degenerative, neoplastic or congenital/developmental ＂origin＂ require osseous reconstruction to ensure structural and functional integrity. Engineering functional bone using combinations of cells, scaffolds and bioactive factors is a promising strategy and a particular feature for future development in the area of hybrid materials which are able to exhibit suitable biomimetic and mechanical properties. This review will discuss the state of the art in this field and what we can expect from future generations of bone regeneration concepts.

关键词： bone tissue engineering regenerative medicine additve manufacturing clinical translation scaffolds