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seasonal variations of rotifers from a high altitude urban shallow water body, La Cantera Oriente (Mexico City, Mexico)

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Chinese Journal of Oceanology and Limnology 2017年第6期35卷 1387-1397页

作者： sergio González GUTIERREZ s.s.s. sARMA s. NANDINI Postgraduate Programme in Marine sciences and Limnology National Autonomous University of Mexico Circuito Exterior sin Ciudad Universitaria Mexico City 04510 Mexico Laboratory of Aquatic Zoology Division of Research & Postgraduate Studies National Autonomous University of Mexico Campus Iztacala Av. de los Barrios No.1 AP 314 Los Reyes Tlalnepantla State of Mexico 54090 Mexico

La Cantera Oriente is a shallow freshwater volcanic water body located at an altitude of 2 270 m above sea level in the Ecological Reserve of san Angel Pedregal of Mexico City （Mexico）. In order to ensure the conservation of its biological heritage including zooplankton, the present work was undertaken to quantify the seasonal changes in the diversity and density of rotifers and the selected physico- chemical variables during 2013-2014. Qualitative analysis of the zooplankton samples yielded 68 rotifer species which represented 24 genera in 15 families. Brachionus calyciflorus Pallas, 1766, B. quadridentatus Hermann, 1783, Polyarthra vulgaris Carlin, 1943, Lecane closterocerca （schmarda, 1859） and Keratella cochlearis （Gosse, 1851） were the most common species. Preston plots of species frequency-density revealed that as many as 30% of the rotifer taxa were dominant throughout the year. The species with high population densities were Brachionus quadridentatus, Lecane closterocerca, Keratella cochlearis, and Lepadellapatella; their peak densities were 2 000, 1 000, 180 and 90 ind./L, all occurring in summer. Canonical correspondence analysis showed that Platyias quadricornis was related to the concentration of phosphates available in the environment and the conductivity, while B. quadridentatus was positively correlated with chlorophyll-a. The trophic status of the lake was eutrophic based on Chl-a content but oligotrophic with relation to the Braehionus： Trichocerca ratio.

关键词： high altitude zooplankton seasonal density dynamics limnology rotifera

sexual dimorphism in water and nitrogen use strategies in Honckenya peploides: timing matters

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Journal of Plant Ecology 2017年第4期10卷 702-712页

作者： Julia sánchez Vilas Rubén Retuerto Organisms and Environment Division Sir Martin Evans BuildingCardiff School of BiosciencesMuseum AvenueCardiff UniversityCardiff CF103AXUK Departamento de Biología Celular y Ecología Área de EcologíaFacultad de BiologíaUniversidade Santiago de CompostelaCampus VidaRúa de Lope Gómez de Marzoas/n15782 Santiago de CompostelaA CoruñaSpain

Aims sexes of dimorphic species often differ in ecophysiological traits and display spatial *** differences have been interpreted as an evolved response of the sexes to meet the specific resource demands associated with *** may differ not only in the amount of resources allocated to reproduction but also in the tim-ing of allocation to *** this study,we hypothesize that as a consequence of their specific resource demands for reproduction,the sexes of the dune plant Honckenya peploides differ in terms of tempo-ral patterns of water use efficiency and nitrogen use and *** Water use efficiency,as inferred from leaf carbon isotope discrimi-nation(Δ^(13)C),nitrogen use,estimated by leaf nitrogen isotope com-position(δ^(15)N),and the foliar carbon and nitrogen contents were measured in males and females at three different points in *** Findings Females had greater water use efficiency than males,regardless of *** ratio of N^(15) to N^(14) did not change with time in males,but significantly decreased in August for *** total N content in the leaf tissues of females decreased as the season progressed,while in males a decrease was only found from April to June and then it remained constant from June to August.A similar pattern,but reversed,was followed by the foliar C/N ***,nega-tive relationships between leafΔ^(13)C and N content were found at all times for males and only at the end of the season for ***,our hypothesis that sex-specific patterns of nitrogen and water use efficiency will depend on time was ***,our results highlight the importance of including time in studies of sex-ual dimorphism,and also the role that physiological specialization plays in meeting the specific demands associated with reproduction.

关键词： cost of reproduction Honckenya peploides leaf nitrogen content sexual dimorphism stable isotopes water use efficiency

Review of endoscopic radiofrequency in biliopancreatic tumours with emphasis on clinical benefits, controversies and safety

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World Journal of Gastroenterology 2016年第37期22卷 8257-8270页

作者： María-Victoria Alvarez-sánchez Bertrand Napoléon Department of Gastroenterology Complejo Hospitalario Universitario de Pontevedra Instituto de Investigación Sanitaria Galicia Sur Department of Gastroenterology Ramsay Générale de Santé Private Hospital Jean Mermoz

Most pancreatic cancers and extrahepatic cholangiocarcinomas are unresectable at the time of diagnosis, and even in case of a resectable cancer, for elderly or patients with coexistent comorbidities, surgery is not an option. Current treatment alternatives in these scenarios are very limited. Biliary stenting with selfexpanding metal stents(sEMs) is the mainstay palliative treatment of biliary obstruction due to unresectable pancreatic cancer or cholangiocarcinoma. Nevertheless, more than 50% of sEMs become occluded after 6 mo due to tumour over- and ingrowth, leading to hospital readmissions and reinterventions that significantly impair quality of life. Regimes of chemotherapy or chemoradiotherapy also provide minimal survival benefits. Therefore, novel therapies are eagerly awaited. Radiofrequency(RF) energy causes coagulative necrosis leading to local destruction of the accessed malignant tissue and has an established role in the treatment of malignancies in several solid organs, especially liver cancers. However, pancreatic and extrahepatic biliary cancers are not easily accessed by a percutaneous route, making the procedure dangerous. Over the past five years, the development of dedicated devices compatible with endoscopic instruments has offered a minimally invasive option for RF energy delivery in biliopancreatic cancers. Emerging experience with endoscopic RF ablation(RFA) in this setting has been reported in the literature, but little is known about its feasibility, efficacy and safety. A literature review makes it clear that RFA in biliopancreatic tumours is feasible with high rates of technical success and acceptable safety profile. Although available data suggest a benefit of survival with RFA, there is not enough evidence to draw a firm conclusion about its efficacy. For this reason, prospective randomized trials comparing RFA with standard palliative treatments with quality-of-life and survival endpoints are required. Anecdotal reportshave also highlig

关键词： Radiofrequency ablation Pancreatic tumour Endobiliary radiofrequency Cholangiocarcinoma Biliary stricture

Green synthesis of glycolic acid through the electrocatalytic reduction of oxalic acid over black TiO_(2): An experimental and theoretical study

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Journal of Energy Chemistry 2025年第1期100卷 544-556页

作者： Hugo Olvera-Vargas Oscar Andrés Jaramillo-Quintero Luis Darío Alarcón León Orlando Castro-Ocampo Christian A.Celaya Marina E.Rincón Jesús Muñiz Instituto de Energías Renovables Universidad Nacional Autónoma de México(IER-UNAM)Priv.Xochicalco s/nCol.CentroTemixcoMorelos.CP 62580Mexico Centro de Nanociencias y Nanotecnología Universidad Nacional Autónoma de México(UNAM)Km 107Carretera Tijuana-EnsenadaEnsenadaB.C.C.P.22800Mexico

Herein,we present the electrocatalytic four-electron hydrogenation of oxalic acid into glycolic acid using black TiO_(2)as an *** acid is an abundant compound found in several sources of organic *** results showed a high selectivity of black TiO_(2)toward glycolic acid,with the formation of glyoxylic acid being the rate-limiting step (glyoxylic acid is the two-electron intermediate).The highest Faradaic efficiency (FE) of 69.6%±8.3% was achieved at 10.2 mA cm^(-2)in 4 h of electrolysis using an H-type cell operated at room temperature,with 50.2%±3.8% of oxalic acid conversion (degradation kinetic constant k=0.0042±0.0001 min-1),58.8%±7.0%of reaction yield and 1.2±0.18 g L-1of glycolic acid production.A theoretical model of black TiO_(2)coming from anatase TiO_(2)was implemented by introducing Ti3+defects,which gave black TiO_(2)the theoretical capability to easily transform oxalic acid into glycolic acid as experimentally *** reaction mechanism was supported and described in detail by density functional theory calculations,which revealed that surface Ti^(3+)states were the main catalytic *** is the first time that a detailed step-by-step mechanism at the atomic level has been proposed for this electrocatalytic reaction,which represents a valuable contribution to the understanding of this process of high energy/environmental *** is also the first time that black TiO_(2)has been used as an electrocatalyst for this sustainable process.

关键词： Chemical energy storage Electrochemical hydrogenation Density functional theory Renewable energy Oxalic acid

Contrast-enhanced harmonic endoscopic ultrasound imaging: Basic principles, present situation and future perspectives

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World Journal of Gastroenterology 2014年第42期20卷 15549-15563页

作者： María-Victoria Alvarez-sánchez Bertrand Napoléon Department of Gastroenterology H?pital Privé Jean Mermoz Department of Gastroenterology Complejo Hospitalario de Pontevedra

Over the last decade, the development of stabilised microbubble contrast agents and improvements in available ultrasonic equipment, such as harmonic imaging, have enabled us to display microbubble enhancements on a greyscale with optimal contrast and spatial resolution. Recent technological advances made contrast harmonic technology available for endoscopic ultrasound(EUs) for the first time in 2008. Thus, the evaluation of microcirculation is now feasible with EUs, prompting the evolution of contrast-enhanced EUs from vascular imaging to images of the perfused tissue. Although the relevant experience is still preliminary, several reports have highlighted contrast-enhanced harmonic EUs(CHEUs) as a promising noninvasive method to visualise and characterise lesions and to differentiate benign from malignant focal lesions. Even if histology remains the gold standard, the combination of CH-EUs and EUs fine needle aspiration(EUs-FNA) can not only render EUs more accurate but may also assist physicians inmaking decisions when EUs-FNA is inconclusive,increasing the yield of EUs-FNA by guiding the puncture with simultaneous imaging of the *** development of CH-EUs has also opened up exciting possibilities in other research areas,including monitoring responses to anticancer chemotherapy or to ethanolinduced pancreatic tissue ablation,anticancer therapies based on ultrasound-triggered drug and gene delivery,and therapeutic adjuvants by contrast ultrasound-induced *** harmonic imaging is gaining popularity because of its efficacy,simplicity and noninvasive nature,and many expectations are currently resting on this *** its potential is confirmed in the near future,contrast harmonic imaging will become a standard practice in EUs.

关键词： Microbubbles Contrast agents Contrast-enhanced harmonic endoscopic ultrasound Pancreatic tumour Gastrointestinal submucosal tumour

A Greener Future: Carbon Nanomaterials from Lignocellulose

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Journal of Renewable Materials 2025年第1期13卷 21-47页

作者： Hebat-Allah s.Tohamy Mohamed El-sakhawy samir Kamel Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Lignocellulosic materials(LCMs),abundant biomass residues,pose signiﬁcant environmental challenges when improperly disposed ***,such as sugarcane bagasse,rice straw,saw dust and agricultural residues,are abun-dant but often burned,contributing to air pollution and greenhouse gas *** review explores the potential of transforming these materials into high-value carbon nanomaterials(CNMs).We explore the potential of transforming these materials into high-value *** employing techniques like carbonization and activa-tion,LCMs can be converted into various CNMs,including carbon nanotubes(CNTs),graphene(G),graphene oxide(GO),carbon quantum dots(CQDs),nanodiamonds(NDs),fullerenes(F),carbon nanoﬁbers(CNFs),and *** different carbon allotropes further enhances their *** derived from cellulose,lignin,and hemicellulose exhibit promising applications in diverseﬁ*** instance,CNTs can be used in energy storage devices like batteries and supercapacitors due to their exceptional electrical conductivity and mechanical ***,CNTs can be incorporated into recycled paper as aﬁre retardant additive,enhancing itsﬂame resistance.G,renowned for its high surface area and excellent electrical conductivity,ﬁnds applications in electronics,sensors,catalysis,and water treatment,where it can be used to adsorb heavy metal ***,owing to their unique optical properties,are used in bioimaging,drug delivery,and optoelectronic *** harnessing the potential of LCMs,we can not only mitigate environmental concerns but also contri-bute to a sustainable *** research is essential to optimize synthesis methods,explore novel applica-tions,and unlock the full potential of these versatile materials.

关键词： Lignocellulosic materials carbon-based nanomaterials carbon allotropes

Hybrid bidirectional quantum communication with different levels of control with simulation

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Communications in Theoretical Physics 2025年第1期77卷 65-91页

作者： Plaban saha Manoj Kumar Mandal Binayak s Choudhury soumen samanta Department of Mathematics Indian Institute of Engineering Science and TechnologyShibpur B.GardenHowrah—711103West BengalIndia Department of Applied science and Humanities Haldia Institute of TechnologyHatiberiaHaldiaPurba Medinipur—721657West BengalIndia

In this paper,we develop a quantum communication protocol for the simultaneous preparation of a two-qubit and a three-qubit state at the positions of two different parties situated spatially *** one party,Alice,it is a remote state preparation of a known two-qubit state while for the other party,Bob,it is a joint remote state preparation with the help of a third party,*** protocol is executed in a hybrid form bi-directionally in the presence of two controllers,Charlie and *** is a hierarchy in the process through different levels of control under which the actions by Alice and Bob are *** is a need for a ten-qubit entangled channel connecting the five *** generation of this channel through a circuit is *** protocol is executed on the IBM Quantum *** also study the effect of noise on our ***,amplitude-damping,bit-flip and phase-flip noisy environments are considered and the corresponding variations of fidelity are theoretically and numerically analyzed.

关键词： remote state preparation joint remote state preparation hierarchy entangled state quantum circuit controlled protocol

Bioactive peptides: A review

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Food Quality and safety 2017年第1期1卷 29-46页

作者： Adrián sánchez Alfredo Vázquez Laboratorio de Investigación en Inmunoquímica Dr.Márquez 162CuauhtémocDoctores06720CDMX Departamento de Química Orgánica Facultad de QuímicaUniversidad Nacional Autónoma de MéxicoMéxico

Bioactive peptides(BP)are organic substances formed by amino acids joined by covalent bonds known as amide or peptide *** some BP exist free in its natural source,the vast majority of known BP are encrypted in the structure of the parent proteins and are released mainly by enzymatic *** BP have been prepared by chemical *** play a significant role in human health by affecting the digestive,endocrine,cardiovascular,immune,and nervous *** are considered the new generation of biologically active regulators;they can prevent oxidation and microbial degradation in foods and also improve the treatment of various diseases and disorders,thus increasing the quality of *** growing interest in BP has incentivized the scientific community and the food industry to exploring the development of new food additives and functional products based on these *** present review highlights the recent findings on the identification,bioassays,and use of BP,as well as their potential use as food additives and in the development of functional products.

关键词： peptides bioactivity marine origin nutraceutical hydrolysis fermentation

New horizons in the endoscopic ultrasonography-based diagnosis of pancreatic cystic lesions

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World Journal of Gastroenterology 2018年第26期24卷 2853-2866页

作者： María-Victoria Alvarez-sánchez Bertrand Napoléon Instituto de Investigación sanitaria Galicia sur Complejo Hospitalario Universitario de Pontevedra Department of Gastroenterology Ramsay Générale de Santé Private Hospital Jean Mermoz

Pancreatic cystic lesions(PCLs) are increasingly being identified because of the widespread use of highresolution abdominal imaging. These cysts encompass a spectrum from malignant disease to benign lesions, and therefore, accurate diagnosis is crucial to determine the best management strategy, either surgical resection or surveillance. However, the current standard of diagnosis is not accurate enough due to limitations of imaging and tissue sampling techniques, which entail the risk of unnecessary burdensome surgery for benign lesions or missed opportunities of prophylactic surgery for potentially malignant PCLs. In the last decade, endoscopic innovations based on endoscopic ultrasonography(EUs) imaging have emerged, aiming to overcome the present limitations. These new EUs-based technologies are contrast harmonic EUs, needle-based confocal endomicroscopy, through-the-needle cystoscopy and through-the needle intracystic biopsy. Here, we present a comprehensive and critical review of these emerging endoscopic tools for the diagnosis of PCLs, with a special emphasis on feasibility, safety and diagnostic performance.

关键词： Intraductal papillary mucinous neoplasm Pancreatic cystic lesions Endoscopic ultrasonography Confocal endomicroscopy Mucinous cystadenoma Through-the-needle cystoscopy serous cystadenoma Through-the-needle forceps biopsy Contrast harmonic endoscopic ultrasonography