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根据加拿大中部花粉记录定量重建植被演变历史的研究

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中国科学（D辑） 2008年第11期38卷 1396-1403页

作者：于革 Hart Catherine mary vetter David Sauchyn 湖泊与环境国家重点实验室中国科学院南京地理与湖泊研究所南京210008 Prairie Adaptation Research Collaborative SKS4S 7J7Canada Department of Biology University of ReginaS4S 0A2Canada Department of Geography University of ReginaS4S 0A2Canada

根据加拿大中部高精度湖泊钻孔的花粉数据,介绍花粉型组合生态系植被单元和现代类比法模拟古植被的研究方法,报告拟合现代植被和验证生态系区后应用在沉积花粉中、重建过去1000年以来古植被的主要结果.该研究表明,在115°～95°W和40°... 详细信息

根据加拿大中部高精度湖泊钻孔的花粉数据,介绍花粉型组合生态系植被单元和现代类比法模拟古植被的研究方法,报告拟合现代植被和验证生态系区后应用在沉积花粉中、重建过去1000年以来古植被的主要结果.该研究表明,在115°～95°W和40°～60°N的北美中部,花粉模拟的现代植被中的北方林型最佳类比率81%,稀树草地型72%,草原和稀树草地型94%,与北美Ⅱ生态系植被分布基本吻合.钻孔沉积花粉的植被模拟反映了过去1000年北美中部经历了中世纪暖期,具有温暖而干旱的气候;小冰期前期寒冷而湿润,后期寒冷而干旱;20世纪具有显著的增温和转干特征.该项研究可为中国学者采用花粉记录探索过去1000年以来植被变化,尤其是在具有特征气候区域、10～100年时间精度的气候植被研究提供良好的研究途径和科学依据.

关键词：沉积花粉表土花粉现代类比法生态系区古植被过去1000年

Protective effects ofLactobacillus plantarum against epithelial barrier dysfunction of human colon cell line NCM460

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World Journal of Gastroenterology 2010年第45期16卷 5759-5765页

作者： mary Pat Moyer INCELL Corporation San AntonioTX 78249United States

AIM: To investigate the effects of Lactobacillus plantarum (L. plantarum ) in the intestinal permeability and expression of tight junction (TJ) using the normal human colon cell line NCM460. METHODS: Paracellular permeability of NCM460 monolayers was determined by transepithelial electrical resistance and dextran permeability. Expression of TJ proteins in NCM460 cell monolayers was detected by Western blotting and quantitative real-time polymerase chain ***: L. plantarum played an important role in increasing transepithelial electrical resistance and decreasing the permeability to macromolecules of NCM460 monolayers against the disruption caused by enteropathogenic Escherichia coli (E. coli ) or enteroinvasive E. coli . L. plantarum also prevented the decrease in the expression of TJ proteins and F-actin in NCM460 ***: L. plantarum can protect against dysfunction of NCM460 intestinal epithelial barrier caused by enteropathogenic E. coli or enteroinvasive E. coli , and thus can be a potential candidate of therapeutic agents for the treatment of intestinal diseases.

关键词： Lactobacillus plantarum NCM460 Tight junction Intestinal barrier

Turning teawaste particles into magnetic bio-sorbents particles for arsenic removal from wastewater:Isotherm and kinetic studies

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Particuology 2024年第4期87卷 179-193页

作者： mary McGeogh Hamza Annath Chirangano Mangwandi School of Chemistry and Chemical Engineering Queen's University BelfastDavid Kier BuildingBT95AGUnited Kingdorm Department of Chermnistry Lancaster UniversityBailrigsLancasterLA14YBUnited Kingdom

The primary objective of this research was to assess the potential of magnetic bleached biochar(MBBC)as a cost-effective adsorbent for arsenic *** achieve this,locally collected tea wastes underwent meticulous cleaning,bleaching,and modifications via thermal and chemical *** non-magnetic and magnetic biochar adsorbents were thoroughly characterized using Fourier transform-infrared spectroscopy(FT-IR)and thermo-gravimetric analysis(TGA).Subsequently,the adsorptive performance of MBBC in removing arsenic from wastewater samples was investigated,considering various crucial parameters such as adsorbent-adsorbate contact time,concentration of As,temperature,adsorbent dosage,and the regeneration-ability of the *** experimental data for the adsorption process were best represented by the Langmuir isotherm,indicating its suitability for the MBBC ***,the MBBC demonstrated a maximum Langmuir adsorption capacity of approximately 714 mg/g at room temperature,highlighting its efficiency as an arsenic ***,the Lagergren's Pseudo-second order kinetic model proved to be the most suitable for describing the adsorption kinetics,confirming the chemisorption nature of the *** results also indicated that the adsorption process is endothermic and feasible,suggesting its viability for practical *** all findings into account,the comprehensive analysis strongly supports the potential use of MBBC as a highly promising and cost-effective adsorbent for efficiently removing arsenic from aqueous *** research contributes valuable insights to the field of wastewater treatment and offers a sustainable and environmentally friendly solution for tackling arsenic contamination in water sources.

关键词： Arsenics Wastewater Adsorption Magnetic bio-char Teawaste

A toast to a zebrafish germ cell induction cocktail

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Science China(Life Sciences) 2024年第6期67卷 1314-1315页

作者： mary C.Mullins Department of Cell and Developmental Biology University of Pennsylvania Perelman School of MedicinePhiladelphia 19104USA

The zebrafish field is ringing in the new year with a publication from Yonghua Sun's laboratory(Wang et al.,2023)of a cocktail of germline factors that can induce all cells of the zebrafish embryo into primordial germ cells(PGCs)at phenomenal *** major advance is not only of great interest to germ cell biologists,but it has important applications to the entire zebrafish field,as shown in Wang et al.(2023).

关键词： fish zebra field

First-principles calculations of the dissolution and coalescence properties of Pt nanoparticle ORR catalysts： The effect of nanoparticle shape

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Nano Research 2015年第5期8卷 1689-1697页

作者： mary Clare Sison Escano Graduate School of Engineering University of Fukui 3-9-1 Bunkyo Fukui 910-8507 Japan

The degradation of Pt nanoparticles （NPs） in fuel cell cathodes leads to the loss of the precious metal catalyst. While the effect of NP size on Pt dissolution has been studied extensively, the influence of NP shape is largely unexplored. Because of the recent development of experimental methods to control the shape of metal NPs, rational guidelines/insights on the shape effects on NP stability are imperative. In this study, first-principles calculations based on density functional theory were conducted to determine the stability of 1-2 nm Pt NPs against Pt dissolution and coalescence with respect to NP shape. Toward dissolution, the stability of the Pt NPs increases in the following order： Hexagonal close-packed 〈 icosahedral 〈 cuboctahedral 〈 truncated octahedral. This trend is attributed to the synergy of the oxygen adsorption strength and the local coordination of the Pt atoms. With respect to coalescence, the size of a NP is related to its propensity to coalesce or detach/migrate to form larger particles. The stability of the Pt NPs was found to increase in the following order： Hexagonal close-packed 〈 truncated octahedral 〈 cuboctahedral 〈 icosahedral, and was correlated with the cohesive energies of the particles. By combining the characteristic stabilities of the shapes, new ＂metal-interfaced＂ Pt-based coreshell architectures were proposed that should be more stable than pure Pt nanoparticles with respect to both dissolution and coalescence.

关键词： Pt nanoparticle ORRcatalyst density functional theory shape dissolution coalescence stability

Use of metaphors when treating unexplained medical symptoms

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World Journal of Clinical Cases 2023年第2期11卷 332-341页

作者： mary V Seeman Department of Psychiatry University of TorontoToronto M5S 1A1OntarioCanada

The words one chooses to describe personal pain mirror current usage, but may also hold echoes of an individual’s lived experience. They may provide clues to the origin of physical symptoms that are medically hard to explain. The aim of this commentary is to propose, on the basis of the available literature, that verbal metaphors can prove effective in the psychotherapy of such conditions. I provide a case history of a 45 year old woman referred to psychiatry because of extreme ‘burning’ pain in her mouth and tongue. She had been to numerous doctors, had undergone a variety of tests, had tried many medical treatments, and had been prescribed a number of different pharmaceutical agents. She had changed her diet, done her daily dental mouth exercises, drunk a lot of water, but the burning continued and interfered, with her job(she was a teacher), her friendships, and her everyday life. This made her angry and recalcitrant to therapy, but the metaphor ‘burning with rage,’ as applicable to her pain, worked to establish a good alliance that led to a decrease of symptoms. Burning Mouth Syndrome is a medically unexplained condition of complex etiology that psychotherapy alone cannot reverse. The literature bears out, however, that the use of metaphors can help to open avenues of psychological exploration that accelerate adaptation to pain and improve quality life.

关键词： Alexithymia Burning mouth syndrome Idioms of distress Menopause Metaphors Pain

Extended Evolutionary Fast Learn-to-Walk Approach for Four-Legged Robots

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Journal of Bionic Engineering 2007年第4期4卷 255-263页

作者： Muh. Anshar mary-Anne Williams Innovation and Technology Research Laboratory Faculty of Information Technology University of Technology Sydney City Campus 15 Broadway Ultimo NSW 2007 Australia

Robot locomotion is an active research area. In this paper we focus on the locomotion of quadruped robots. An effective walking gait of quadruped robots is mainly concerned with two key aspects, namely speed and stability. The large search space of potential parameter settings for leg joints means that hand tuning is not feasible in general. As a result walking parameters are typically determined using machine learning techniques. A major shortcoming of using machine learning techniques is the significant wear and tear of robots since many parameter combinations need to be evaluated before an optimal solution is found. This paper proposes a direct walking gait learning approach, which is specifically designed to reduce wear and tear of robot motors, joints and other hardware. In essence we provide an effective learning mechanism that leads to a solution in a faster convergence time than previous algorithms. The results demonstrate that the new learning algorithm obtains a faster convergence to the best solutions in a short run. This approach is significant in obtaining faster walking gaits which will be useful for a wide range of applications where speed and stability are important. Future work will extend our methods so that the faster convergence algorithm can be applied to a two legged humanoid and lead to less wear and tear whilst still developing a fast and stable gait.

关键词： legged-robots locomotion learning genetic convergence walking gaits

Efficient Approach for Resource Allocation in WPCN Using Hybrid Optimization

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Computers, Materials & Continua 2022年第7期72卷 1275-1291页

作者： Richu mary Thomas Malarvizhi Subramani Department of Electronics and Communication Engineering SRMISTKattankulathur603203India

The recent aggrandizement of radio frequency(RF)signals in wireless power transmission combined with energy harvesting methods have led to the replacement of traditional battery-powered wireless networks since the blooming RF technology provides energy renewal of wireless devices with the quality of service(QoS).In addition,it does not require any unnecessary alterations on the transmission hardware side.A hybridized global optimization technique uniting Global best and Local best(GL)based particle swarm optimization(PSO)and ant colony optimization(ACO)is proposed in this paper to optimally allocate resources in wireless powered communication networks(WPCN)through coordinated operation of communication groups,in which the wireless energy transfer and information sharing take place concomitantly by the aid of a cooperative relay positioned in between the communicating *** designed algorithm assists in minimizing power consumption and maximizes the weighted sum rate at the end-user *** the principal target of the system is coordinated optimization of energy beamforming along with time and energy allocation to reduce the total energy consumed combined with assured information rates of the communication *** outputs are presented to manifest the proposed system’s performance to verify the analytical results via simulations.

关键词： Wireless powered communication networks cooperative communication relay hybrid optimization technique ant colony optimization particle swarm optimization

Prognostic factors for a favorable outcome after varicocele repair in adolescents and adults

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Asian Journal of Andrology 2016年第2期18卷 217-221,J0004页

作者： mary K Samplaski Keith A Jarvi Institute of Urology University of Southern California Los Angeles CA USA Division of Urology Department of Surgery Mount Sinai Hospital University of TorontoToronto Ontario Canada.

The effect of varicocele repair on male fertility remains controversial. It would be helpful to determined which men would benefit most from varicocele repair, and target repair efforts at those individuals. A detailed review of the literature on prognostic factors for varicocele repair was performed using the PubMed NLM database. We found that the best predictor of postvaricocelectomy semen parameters is the preoperative semen parameters. The greatest improvements in semen parameters were found in men with larger varicoceles. While there is controversy, higher testosterone, younger age and larger testis size, in some studies predict for improvements in semen parameters postvaricocelectomy. A nomogram has been developed to predict the postvaricocelectomy semen parameters based on the preoperative semen parameters, varicocele grade and the age of the man （***. com）. Limited data consistently demonstrates the greatest improvements in DNA fragmentation rates in men with higher baseline DNA fragmentation rates. With respect to reproductive outcomes, higher baseline sperm density consistently predicts for natural pregnancy or assisted reproductive technology （ART） pregnancy rates. In addition, varicocele repair does seem to reduce the need for more invasive modalities of ART. In conclusion, we can now start to use specific parameters such as baseline semen quality, varicocele grade and patient age to predict post-repair semen oualitv and fertility potential following varicocelectomy.

关键词： prediction prognosis varicocelectomy varicoceles