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Fast synthesis of gold nanoparticles by cold atmospheric pressure plasma jet in the presence of Au^(+) ions and a capping agent

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Plasma Science and Technology 2024年第7期26卷 108-115页

作者： Tatiana HABIB josé Mauricio A.CAIUT Bruno CAILLIEr Laboratoire Diagnostics des Plasmas Hors Equilibre(DPHE) Universitéde ToulouseINU ChampollionAlbi 81000France Department of Chemistry The Nanomaterials and Luminescent Systems GroupFaculty of PhilosophyScience and Letters at Ribeirão PretoUniversity of São PauloRibeirão Preto-SP 14040-901Brazil

Homogeneous gold nanoparticles were synthesized under atmospheric pressure using a nonthermal helium plasma jet in a single-step process.A current power supply was used to generate the plasma discharge rich in diverse reactive *** species induce rapid chemical reactions responsible for the reduction of the gold salts upon contact with the liquid *** this study,spherical and monodispersed gold nanoparticles were obtained within 5 min of plasma exposure using a solution containing gold(Ⅲ)chloride hydrate(HAuCl_(4))as a precursor and polyvinylpyrrolidone(PVP)as a capping agent to inhibit *** formation of these metal nanoparticles was initially perceptible through a visible change in the sample's color,transitioning from light yellow to a red/pink *** was subsequently corroborated by UVvis spectroscopy,which revealed an optical absorption in the 520-550 nm range for Au NPs,corresponding to the surface plasmon resonance(SPr)*** investigation into the impact of various parameters,including plasma discharge duration,precursor and capping agent concentrations,was carried out to optimize conditions for the formation of well-separated,spherical gold *** light scattering(DLS)was used to measure the size of these nanoparticles,transmission electron microscopy(TEM)was used to observe their morphology and X-ray diffraction(XrD)was also employed to determine their crystallographic *** results confirm that homogeneous spherical gold nanoparticles with an aver.ge diameter of 13 nm can be easily synthesized through a rapid,straightforward,and environmentally friendly approach utilizing a helium atmospheric pressure plasma.

关键词： gold nanoparticles non-thermal plasma jet helium DBD

Capsule endoscopy and panendoscopy:A journey to the future of gastrointestinal endoscopy

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World Journal of gastroenterology 2024年第10期30卷 1270-1279页

作者： Bruno rosa joséCotter Department of gastroenterology Hospital da Senhora da OliveiraGuimarães 4835-044Portugal Life and Health Sciences research Institute School of MedicineUniversity of MinhoBraga 4710-057Portugal ICVS/3B's PT Government Associate LaboratoryBraga 4710-057Portugal

In 2000,the small bowel capsule revolutionized the management of patients with small bowel ***,the technological development achieved by the new models of double-headed endoscopic capsules,as miniaturized devices to evaluate the small bowel and colon[pan-intestinal capsule endoscopy(PCE)],makes this non-invasive procedure a disruptive concept for the management of patients with digestive *** technology is expected to identify which patients will require conventional invasive endoscopic procedures(colonoscopy or balloon-assisted enteroscopy),based on the lesions detected by the capsule,i.e.,those with an indication for biopsies or endoscopic *** use of PCE in patients with inflammatory bowel diseases,namely Crohn’s disease,as well as in patients with iron deficiency anaemia and/or overt gastrointestinal(gI)bleeding,after a non-diagnostic upper endoscopy(esophagogastroduodenoscopy),enables an effective,safe and comfortable way to identify patients with relevant lesions,who should undergo subsequent invasive endoscopic *** recent development of magnetically controlled capsule endoscopy to evaluate the upper.gI tract,is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract,from mouth-to-anus,meeting the expectations of the early developers of capsule endoscopy.

关键词： Non-invasive endoscopy Panendoscopy Magnetically controlled capsule endoscopy Crohn’s disease Digestive bleeding

Surgical risk for patients with Chagasic achalasia and its correlation with the degree of esophageai dilation

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World Journal of gastroenterology 2005年第37期11卷 5840-5844页

作者： josé garcia Neto roberto de Cleva Bruno Zilberstein Joaquim josé gama-rodr.gues Surgery Division Hospital das Clínicas Federal University of Goiás Medical School Goiás Brazil gastroenterology Department Digestive Tract Surgery Division Hospital das Clínicas University of Sao Paulo Medical School So Paulo Brazil

AIM： To analyze the risk of cardiovascular complications in patients with indication for surgical treatment of Chagasic esophageal achalasia and to correlate the surgical risks with the degree of esophageal dilation, thereby proposing a risk scale index. METHODS： One hundred and twenty-four patients with Chagasic esophageal achalasia, who received surgical treatment at the Hospital das Clinicas of the Federal University of goiás, were included in this study. The patients were mostly related to the postoperative complications due to the cardiovascular system. All the patients were submitted to：（1） clinical history to define the cardiac functional class （New York Heart Association）; （2） conventional 12-lead electrocardiogram at rest; and （3） contrast imaging of the esophagus to determine esophageal dilatation according to rezende＇s classification of Chagasic megaesophagus. rESULTS： An assessment of the functional classification （FC） of heart failure during the preoperative period determined that 67 patients （54.03%） were assigned functional class Ⅰ （FC Ⅰ）, 46 patients （37.09%） were assigned functional class Ⅱ （FC Ⅱ）, and 11 patients （8.87%） were assigned functional class Ⅲ （FC Ⅲ）. None of the patients were assigned to functional class Ⅳ （FC Ⅳ）. There was a positive correlation between the functional class and the postoperative complications （FC Ⅰ×FC Ⅱ： P〈0.001; FC Ⅰ×FC Ⅲ： P〈0.001）. The ECg was normal in 44 patients （35.48%） and presented abnormalities in 80 patients （64.52%）. There was a significant statistical correlation between abnormal ECg （arrhythmias and primary change in ventricular repolarization） and postoperative complications （P〈0.001）. With r.gard to the classification of the Chagasic esophageal achalasia, the following distribution was observed： group Ⅱ, 53 patients （42.74%）; group Ⅲ, 37 patients （29.83%）; and group Ⅳ, 34 patients （27.41%）. There was a positive correlation between the degree of esophageal dilation and the increase in postoperative compli

关键词： Postoperative Chagas' disease Surgical risk Chagasic achalasia Cardiovascular risk

gut microbiota:a potential therapeutic target for Parkinson's disease

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Neural r.generation research 2021年第2期16卷 287-288页

作者： joséFidel Baizabal-Carvallo Department of Science and Engineering University of GuanajuatoGuanajuatoMéxico

Parkinson's disease(PD)is a neurodegenerative disorder characterized by accumulation ofα-synuclein in neurons of the central nervous system(CNS).The pathogenesis of PD is complex and only partially *** evidence pointed to the basal ganglia as the source of the motor manifestations of PD,and likely the or.gin of the pathological *** the last two decades。

关键词： process. therapeutic pathogenesis

An Efficient representation of Quadtrees and Bintrees for Multiresolution Terrain Models

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geo-Spatial Information Science 2011年第3期14卷 198-206页

作者： Yusnier Valle josé Ortiz Center of geoinformatics and Digital Signals University of Informatics Sciences Dean of the Faculty 1 University of Informatics Sciences

A space-filling curve in 2,3,or higher dimensions can be thought as a path of a continuously moving *** its main goal is to preserve spatial proximity,this type of curves has been widely used in the design and implementation of spatial data structures and nearest neighbor-finding *** paper is essentially focused on the efficient representation of Digital Ele-vation Models(DEM) that entirely fit into the main *** propose a new hierarchical quadtree-like data structure to be built over domains of unrestricted size,and a representation of a quadtree and a binary triangles tree by means of the Hilbert and the Sierpinski space-filling curves,respectively,taking into account the hierarchical nature and the clustering properties of this kind of *** triangulation schemes are described for the space-filling-curves-based approaches to efficiently visualize multiresolu-tion surfaces.

关键词： bintrees quadtrees space-filling curves spatial data structures digital terrain models

Parameter identification for a damage phase field model using a physics-informed neural network

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Theoretical & Applied Mechanics Letters 2023年第3期13卷 229-246页

作者： Carlos J.g.rojas jos L.Boldrini Marco L.Bittencourt Department of Integrated System School of Mechanical EngineeringUniversity of CampinasRua Mendeleyev 200CampinasSPZip Code 13083-860Brazil

This work applies concepts of artificial neural networks to identify the parameters of a mathematical model based on phase fields for damage and *** mechanics is the part of the continuum mechanics that models the effects of micro-defect formation using state variables at the macroscopic *** equations that define the model are derived from fundamental laws of physics and provide important relationships among state *** using the model considered in this work produce good qualitative and quantitative results,but many parameters must be adjusted to reproduce certain material *** identification of model parameters is considered by solving an inverse problem that uses pseudo-experimental data to find the best values that fit the *** apply physics informed neural network and combine some classical estimation methods to identify the material parameters that appear in the damage equation of the *** strategy consists of a neural network that acts as an approximating function of the damage evolution with output r.gularized using the residue of the differential *** stages of optimization seek the best possible values for the neural network and the material *** training alternates between the fitting of only the pseudo-experimental data or the total loss that includes the r.gularizing *** test the robustness of the method to noisy data and its generalization capabilities using a simple physical case for the damage *** procedure deals better with noisy data in comparison with a more standard PDE-constrained optimization method,and it also provides good approximations of the material parameters and the evolution of damage.

关键词： Deep learning Damage Phase field Parameter fitting Inverse analysis

Fr.gmentation patterns and systematic transitions of the forested landscape in the upper Amazon r.gion, Ecuador 1990-2008

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Journal of Forestry research 2014年第2期25卷 301-309页

作者： Santiago Bonilla-Bedoya Juan r.Molina josé E.Macedo-Pezzopane Miguel A.Herrera-Machuca DepartaTento de Ingeniería Forestal E.T.S.I.A.M.Universidad de CórdobaCaTpus de Excelencia Internacional Agroali Tentario (ceiA3) Secretaria Nacional de Educación Superior CienciaTecnología e Innovación del EcuadorWhy Tper E7-37 y Alpallana Quito. Ecuador Departa Tento de Engenharia Florestal Universidade Federal do Espírito Santo

The analysis of the systematic transitions in the forested landscape and the study of the forest fr.gmentation patterns allow us to deepen our understanding of the changes in the vegetation ground cover. The importance of knowing the intricate patterns of the land usage of the upper basin of the Amazon r.gion is widely recognized. This zone is one of the most diverse biological areas in the world, is home to large areas of mature tropical cloud forest and demonstrates high probabilities of stable climatic conditions in light of global warming. The research quan- tiffed systematic transitions through the ＂loss＂ and ＂gain＂ of the different categories of landscape during the eighteen-year study period of the Ecuadorian Amazon r.gion （EAr）, the forest fr.gmentation patterns were also analyzed based on a set of indicators. Therefore, with respect to the entirety of the landscape, the results r.gistered for the ground cover.ge in forested areas during the first period （1990-2000）, show a decrease of 6.99% and an increase of 0.68%; and during the second period （2000-2008）, show a decrease of 3.99% and an increase of 2.14%. It demonstrated that forest and agricultural areas tended to replace or be replaced by herbaceous vegetation faster than expected fortuitously. Finally, the indices of fr.gmentation signaled intense changes during the 1990-2000 period with a reduction during the period 2000-2008. Per- centages r.gistered in the Largest Patch Index （LPI） were between 79.58%; 52.39% and 49.99% respectively; while the Patch Density （PD） varied between 0.04; 0.06 and 0.07. This suggests the propensity of for- est cover to remain intact. The results of this investigation suggest a tendency towards stability in Ecuador＇s Amazon landscape. Within the framework for development and management of this area, the tendency is natural r.generation. This permits a consolidation of the conservation, reforestation, forestation and agricultural forestry plans, pr.grams and systems for the

关键词： Ecuadorian Amazon systematic transitions fr.gmentation natural r.generation

Strain Influence on the Precipitation Kinetic Nb-V Microalloyed HSLA Steel

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Journal of Iron and Steel research International 2011年第S1期18卷 278-281页

作者： Cartaya Elio Armando Cabrera josé María Prado josé Manuel Departamento de Ciencia de Materiales e Ingeniería Metalúrgica ETSEIBUniversidad Politécnica de Catalu a Av.Diagonal 64708028 BarcelonaSpain Departamento de Manufactura y Materiales Facultad de Ingeniería MecánicaUniversidad de Oriente90400 Santiago de CubaCuba Fundación CTM Centro Tecnológico Av.Bases de Manresa 108242 ManresaSpain

The strain induced effect on the precipitation kinetics of a high strength low alloy (HSLA) steel microalloyed with Nb-V was *** stress relaxation method was employed to determine the dependence of the precipitation-time-temperature curves (PTT) on previous *** tests were performed over a temperature range of 850 to 1150 oC at a constant strain rate of 0.1 s-1 at three deformation levels,namely 5,15 and 25 *** emission scanning electron microscopy (FESEM) was used to study the pr.gress of precipitation on samples obtained by interrupted relaxation test at different *** display the acceleration kinetics at increasing *** models are discussed and compared with the present experimental results.

关键词： strain induced precipitation kinetic HSLA stress relaxation PTT

Seed Priming with Beta-Amino Butyric Acid Improves Abiotic Stress Tolerance in rice Seedlings

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rice science 2016年第5期23卷 242-254页

作者： Kolothodi Chandran JISHA jos Thomas PUTHUr Plant Physiology and Biochemistry Division Department of Botany University of CalicutC.U.Campus

We studied the influence of seed priming with beta-amino butyric acid（BABA） on the growth, physiological and biochemical parameters of seedlings with varied abiotic stress tolerance, which were raised and grown under unstressed and stressed（NaCl/PEg-6000） conditions. Under stressed conditions, the growth of rice seedlings was less when compared to control plants. After BABA priming, the seedling growth increased both under unstressed and stressed conditions as compared to the respective controls. BABA priming of rice seeds caused increase in the photosynthetic pigment content of the leaves, modified the chlorophyll a fluorescence related parameters and also enhanced the photosystem activities of seedlings when compared to their respective non-primed controls. BABA priming also caused increased mitochondrial activities of the rice seedlings. Moreover, BABA priming significantly reduced malondialdehyde content in the seedlings and also resulted in accumulation of proline especially in the NaCl tolerant variety Vyttila 6. BABA seed priming also enhanced the activity of nitrate reductase enzyme and activities of antioxidant enzymes like guaiacol peroxidase and superoxide dismutase. The presence of BABA was detected by high performance thin layer chromatography analysis in the rice seeds whereas in the seedlings it was not detected. Thus, it can be inferred that the seed priming effect of BABA mainly occurred within the seeds, which was further carried to the seedlings. It is concluded that BABA priming of seeds improved the drought and salinity stress tolerance of all the three rice varieties and it was significantly evident in the drought tolerant variety Vaisakh and NaCl tolerant variety Vyttila 6, when compared to the stress sensitive variety Neeraja.

关键词： abiotic stress drought mitochondrial activity photochemical activity seed priming rice beta-amino butyric acid