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Porosity,cracks,and mechanical properties of additively manufactured tooling alloys:a review

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Advances in Manufacturing 2022年第2期10卷 175-204页

作者： Prveen Bidare Amaia jimenez Hany Hassanin Khamis Essa School of Mechanical Engineering University of BirminghamBirminghamUK TECNUN Escuela de Ingenieria Universidad de NavarraManuel de Lardizabal 15San Sebastian20018Spain School of Engineering Technologyand DesignCanterbury Christ Church UniversityCanterbury CT11QUUK

Additive manufacturing(AM)technologies are currently employed for the manufacturing of completely functional parts and have gained the attention of hightechnology industries such as the aerospace,automotive,and biomedical *** is mainly due to their advantages in terms of low material waste and high productivity,particularly owing to the flexibility in the geometries that can be *** the tooling industry,specifically the manufacturing of dies and molds,AM technologies enable the generation of complex shapes,internal cooling channels,the repair of damaged dies and molds,and an improved performance of dies and molds employing ***,a reviewof AM processes and materials applied in the tooling industry for the generation of dies and molds is *** technologies used for tooling applications and the characteristics of the materials employed in this industry are first *** addition,the most relevant state-of-the-art approaches are analyzed with respect to the process parameters and microstructural and mechanical properties in the processing of high-performance tooling materials used in AM ***,studies on the AM of ferrous(maraging steels and H13 steel alloy)and non-ferrous(stellite alloys and WC alloys)tooling alloys are also analyzed.

关键词： Additive manufacturing(AM) Tooling alloys Super alloys Hybrid manufacturing Post processing

Laparoscopic approach in gastrointestinal emergencies

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World Journal of Gastroenterology 2016年第9期22卷 2701-2710页

作者： Rosa M jimenez Rodriguez Juan José Segura-Sampedro Mercedes Flores-Cortés Francisco López-Bernal Cristobalina Martín Verónica Pino Diaz felipe Pareja Ciuro Javier Padillo Ruiz Department of Surgery Hospital Universitario Virgen del Rocio 41013 Sevilla Spain Hospital Universitario Son Espases 07010 Palma de Mallorca Spain

This review focuses on the laparoscopic approach to gastrointestinal emergencies and its more recent indications. Laparoscopic surgery has a specific place in elective procedures, but that does not apply in emergency situations. In specific emergencies, there is a huge range of indications and different techniques to apply, and not all of them are equally settle. We consider that the most controversial points in minimally invasive procedures are indications in emergency situations due to technical difficulties. Some pathologies, such as oesophageal emergencies, obstruction due to colon cancer, abdominal hernias or incarcerated postsurgical hernias, are nearly always resolved by conventional surgery, that is, an open approach due to limited intraabdominal cavity space or due to the vulnerability of the bowel. These technical problems have been solved in many diseases, such as for perforated peptic ulcer or acute appendectomy for which a laparoscopic approach has become a wellknown and globally supported procedure. On the other hand, endoscopic procedures have acquired further indications, relegating surgical solutions to a second place; this happens in cholangitis or pancreatic abscess drainage. This endoluminal approach avoids the need for laparoscopic development in these diseases. Nevertheless, new instruments and new technologies could extend the laparoscopic approach to a broader array of potentials procedures. There remains, however, a long way to go.

关键词： Minimally invasive surgery Gastrointestinal surgery Emergency surgery Digestive emergencies Abdominal emergencies

Chiral Symmetry Breaking for Fermions Charged under Large Lie Groups

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Communications in Theoretical Physics 2019年第4期71卷 410-416页

作者： felipe J.Llanes-Estrada Alexandre Salas-Bernardez Depto.Fisica Teorica Universidad Complutense de Madrid

We reexamine the dynamical generation of mass for fermions charged under various Lie groups with equal charge and mass at a high Grand Uni?cation scale, extending the Renormalization Group Equations in the perturbativ... 详细信息

关键词： standard model group running fermion mass grand unification scale

Pairs of integers which are mutually squares

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Science China Mathematics 2017年第9期60卷 1633-1646页

作者： CHAKRABORTY Kalyan jimenez URROZ Jorge PAPPALARDI Francesco Department of Mathematics Harish Chandra Research InstituteAllahabad 211019India Department of Mathemdticas Universidad Politecnica de CatalunyaBarcelona 08034Spain Dipartimento di Matematica Universith Roma TreRoma 1-00146Italy

We derived an asymptotic formula for the number of pairs of integers which are mutually squares. Earlier results dealt with pairs of integers subject to the restriction that they are both odd, co-prime and squarefree. Here we remove all these restrictions and prove （similar to the best known one with restrictions） cx2/log X with an absolute constant c that the number of such pair of integers upto a large real X is asymptotic to which we give explicitly. Our error term is also compatible to the best known one.

关键词： quadratic reciprocity mutually squares Jacobi symbol

Compartmentalized necroptosis activation in excitotoxicityinduced axonal degeneration: a novel mechanism implicated in neurodegenerative disease pathology

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Neural Regeneration Research 2019年第8期14卷 1385-1386页

作者： Macarena S. Arrazola felipe A. Court Center for Integrative Biology Faculty of Sciences Universidad Mayor de Chile Santiago CnileFONDAP Center for Geroscience Brain Health and Metabolism Santiago Chile Buck Institute for Research on Ageing Novato San Francisco CA USA

Excitotoxicity and neuronal cell death: Glutamate is the main excitatory neurotransmitter of the central nervous system and functionally involved in most brain activities, including brain development, synaptic plasticity, learning and memory. Exc让atory synaptic transmission is primarily mediated by ligana-gated ion channels, including a-amino-3-hydroxy-5-methylisoxazoIe-4-propionic acid (AMPA), N-methyl-D-aspartate (NMDA) and kainate receptors. Activation of glutamate receptors, particularly NMDA receptors, usually leads to calcium influx, whicn can act as a second messenger for several processes to mediate synaptic activity and brain function. Nevertheless, excessive release of glutamate neurotransmitter may produce intracellular calcium overload, leading to a cascade of events mediating cytoskeleton damage accompanied w让h reactive oxygen species (ROS) generation, mitochondrial dysfunction and ultimately neuronal cell death. These toxic effects of glutamate are known as excitotoxicity. Neuronal excitotoxicity has been linked to several acute and chronic brain diseases, such as stroke/ischemia, epilepsy and a range of neurodegenerative disorders, including Alzheimer's disease (AD), Huntingtons disease, amyotrophic lateral sclerosis (ALS) and Parkinsons disease (PD), contributing to the neuronal lost in different brain regions. Unfortunately, treating nervous system disorders with general glutamate receptor blockers has been associated with undesirable side effects, becoming increasingly necessary to unravel downstream effectors in the excitotoxicity-dependent cell death pathway in order to develop novel therapeutic strategies.

关键词： Compartmentalized necroptosis activation excitotoxicityinduced axonal neurodegenerative disease

Factors affecting the spatial distribution and breeding habitat of an insular cliff-nesting raptor community

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Current Zoology 2018年第2期64卷 173-181页

作者： Beneharo RODRIGUEZ Airam RODRiGUEZ felipe SIVERIO Manuel SIVERIO Canary Islands' Ornithology and Natural History Group (GOHNIC) La Malecita s/n 38480 Buenavista del NorteTenerife Canary Islands Spain Department of Evolutionary Ecology Estacion Biologica de DoSana (CSIC)Avda. Americo Vespucio s/n Seville 41092 Spain

The specific spatial distribution and habitat association--strongly influenced by environmental fac- tors or competitive interactions--are major issues in ecology and conservation. We located and georeferenced nesting sites of five cliff-nesting raptors （Egyptian vulture Neophron percnopterus [a locally extinct species], common buzzard Buteo buteo, osprey Pandion haliaetus, common kes- trel Falco tinnunculus, Barbary falcon Falco peregrinus pelegrinoides）, and common raven Corvus corax on one of the most biodiverse hotspot within the Canary Islands （Teno, Tenerife）. We used generalized linear models to evaluate the factors affecting abundance, richness, and intra- and interspecific interactions. Raptor abundance increased with slope, shrub-covered area, and habitat diversity, and decreased with altitude, and forested and grassed areas. Richness increased with slope and decreased with altitude. Threatened species （osprey, Barbary falcon, and raven） occu- pied cliffs farther away from houses and roads, and more rugged areas than the non-threatened species. The models suggested that the probability of cliff occupation by buzzards, falcons, and rav- ens depended only on inter-specific interactions. Buzzard occupation increased with the distance to the nearest raven and kestrel nests, whereas falcons and ravens seek proximity to each other. Teno holds between 75% and 100% of the insular breeding populations of the most endangered species （osprey and raven）, indicating the high conservation value of this area. Our study suggests that the preservation of rugged terrains and areas of low human pressure are key factors for raptor conservation and provide basic knowledge on the community structure and habitat associations to develop appropriated management actions for these fragile island populations.

关键词： Canary Islands competitive interactions human disturbances habitat threatened species.

On a Class of Solutions to the Generalized Derivative Schrodinger Equations

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Acta Mathematica Sinica,English Series 2019年第6期35卷 1057-1073页

作者： felipe LINARES Gustavo PONCE Gleison N.SANTOS IMPA Estrada Dona Castorina 110 Rio de Janeiro 22460-320 RJ Brazil University of California Santa Barbara CA 93106 USA Universidade Federal do Piaui-UFPI.Campus Ministro Petronio Portella Teresina 64049-550 PI Brazil

In this work we shall consider the initial value problem associated to the generalized derivative Schr?dinger(gDNLS) equations ■ and ■ Following the argument introduced by Cazenave and Naumkin we shall establish the local well-posedness for a class of small data in an appropriate weighted Sobolev space. The other main tools in the proof include the homogeneous and inhomogeneous versions of the Kato smoothing effect for the linear Schr?dinger equation established by Kenig–Ponce–Vega.

关键词： Derivative nonlinear Schrodinger local well-posedness

Synthetic Time Series Generation Model for Analysis of Power System Operation and Expansion with High Renewable Energy Penetration

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 849-858页

作者： Rodrigo Palma-Behnke Jorge Vega-Herrera felipe Valencia Oscar Nunez-Mata Energy Center Department of Electrical EngineeringFaculty of Mathematical and Physical SciencesUniversity of ChileSantiagoChile Department of Electrical Engineering University of AntofagastaAntofagastaChile School of Electrical Engineering University of Costa RicaSan PedroCosta Rica

The increasing integration of renewable energy sources into current power systems has posed the challenge of adequately representing the statistical properties associated with their variable power generation. In this paper, a novel procedure is proposed to select a proper synthetic time series generation model for renewable energy sources to analyze power system problems. The procedure takes advantage of the objective of the specific analysis to be performed and the statistical characteristics of the available time series. The aim is to determine the suitable model to be used for generating synthetic time series of renewable energy sources. A set of indicators is proposed to verify that the statistical properties of synthetic time series fit the statistical properties of the original data. The proposal can be integrated into systematic tools available for data analysis without compromising the representation of the statistical properties of the original time series. The procedure is tested using real data from the New Zealand power system in a mid-term analysis on integrating wind power plants into the power system. The results show that the proposed procedure reduces the error obtained in analyzing power systems compared with reference models.

关键词： Time series analysis renewable energy source solar energy stochastic process statistical analysis wind energy

Application of artificial intelligence in the diagnosis and treatment of hepatocellular carcinoma: A review

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World Journal of Gastroenterology 2020年第37期26卷 5617-5628页

作者： Miguel jimenez Perez Rocio Gonzalez Grande UGC de Aparato Digestivo Unidad de Hepatologia-Trasplante HepaticoHospital Regional Universitario de MalagaMalaga 29010Spain

Although artificial intelligence(AI)was initially developed many years ago,it has experienced spectacular advances over the last 10 years for application in the field of medicine,and is now used for diagnostic,therapeutic and prognostic purposes in almost all *** application in the area of hepatology is especially relevant for the study of hepatocellular carcinoma(HCC),as this is a very common tumor,with particular radiological characteristics that allow its diagnosis without the need for a histological ***,the interpretation and analysis of the resulting images is not always easy,in addition to which the images vary during the course of the disease,and prognosis and treatment response can be conditioned by multiple *** vast amount of data available lend themselves to study and analysis by AI in its various branches,such as deeplearning(DL)and machine learning(ML),which play a fundamental role in decision-making as well as overcoming the constraints involved in human *** is a form of AI based on automated learning from a set of previously provided data and training in algorithms to organize and recognize *** is a more extensive form of learning that attempts to simulate the working of the human brain,using a lot more data and more complex *** review specifies the type of AI used by the various ***,welldesigned prospective studies are needed in order to avoid as far as possible any bias that may later affect the interpretability of the images and thereby limit the acceptance and application of these models in clinical *** addition,professionals now need to understand the true usefulness of these techniques,as well as their associated strengths and limitations.

关键词： Artificial intelligence Machine learning Hepatocellular carcinoma Diagnosis Treatment Prognosis