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Stress tensors and quantification of fracture patterns to analyze connectivity and potential fluid flow in a mesa landform of the Northern Andes

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Journal of Mountain Science 2024年第1期21卷 271-291页

作者： GARCÍA-ARIAS Sergio VELANDIA Francisco ALVAREZ Angélica SANABRIA-GÓMEZ JoséD TARAZONA Yessenia VARGAS María Camila escuela de Geología Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia escuela de Física Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia

This work applies stress tensors inversions and quantification of fracture patterns along the Mesa de Los Santos, in the Eastern Cordillera of Colombia, to better understand the potential fluid flow. It thus contributes to the conceptual hydrogeological model. The area was subdivided into three blocks, separated by the NW Potreros and the Los Santos faults, having minor inner faults of different orientations. This separation facilitates the analysis of the fractures measured in the field, which in general show high dip angles and a conjugate geometry in the northern block, tension fractures(Mode I) in the central block, and a random distribution in the southwestern block. WinTensor treatment of slickensides yielded a maximum horizontal stress(SHmax) of 111o, which coincides with the WNW-ESE tensor observed from the conjugate and tension joints. We then used Frac Pa Q to generate interpolation maps of fracture intensity and density. The maps show the highest values in the central block and the lowest in the northern block,where the precipitation is higher, causing intensive rock weathering and homogenization of the fracture planes. Although the highest values of connectivity by line are found to the south of the mesa, we suggest the possibility of greater flow from the recharge zone(NE) along bedding planes and open NW-SE fractures.

关键词： Mesa de Los Santos Colombia Win-Tensor FracPaQ Strike-slip faults Fractured aquifers

Kinematic analysis of flexible bipedal robotic systems

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： R.FAZEL A.M.SHAFEI S.R.NEKOO department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous researchers.What distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic systems.This is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases considerably.Moreover,the human leg bones that are involved in walking are supported by viscoelastic muscles and ligaments.Therefore,for achieving more exact results,it is essential to model the robot links with viscoelastic properties.To this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of motion.The most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational force.The extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned goal.To overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue problem.By solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are determined.The effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of robotic systems are also studied.The findings o

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 102-111页

作者： Esteban Diaz Edgar Leonardo Salamanca-Medina Roberto Tomas departamento de Ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction projects.The high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test fields.The present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research papers.The selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive strength.despite the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing works.Consequently,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

Single-neuron neurodegeneration as a degenerative model for Parkinson’s disease

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Neural Regeneration Research 2024年第3期19卷 529-535页

作者： Sandro Huenchuguala Juan Segura-Aguilar escuela de Tecnología Médica Facultad de SaludUniversidad Santo TomásLos CarrerasOsornoChile Molecular&Clinical Pharmacology Instituto de Ciencias Biomedicas(ICBM)Faculty of medicineUniversity of ChileIndependenciaSantiagoChile

The positive effect of levodopa in the treatment of Parkinson’s disease,although it is limited in time and has severe side effects,has encouraged the scientific community to look for new drugs that can stop the neurodegenerative process or even regenerate the neuromelanin-containing dopaminergic nigrostriatal neurons.Successful preclinical studies with coenzyme Q10,mitoquinone,isradipine,nilotinib,TCH346,neurturin,zonisamide,deferiprone,prasinezumab,and cinpanemab prompted clinical trials.However,these failed and after more than 50 years levodopa continues to be the key drug in the treatment of the disease,despite its severe side effects after 4–6 years of chronic treatment.The lack of translated successful results obtained in preclinical investigations based on the use of neurotoxins that do not exist in the human body as new drugs for Parkinson’s disease treatment is a big problem.In our opinion,the cause of these failures lies in the experimental animal models involving neurotoxins that do not exist in the human body,such as 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and 6-hydroxydopamine,that induce a very fast,massive and expansive neurodegenerative process,which contrasts with the extremely slow one of neuromelanin-containing dopaminergic neurons.The exceedingly slow progress of the neurodegenerative process of the nigrostriatal neurons in idiopathic Parkinson’s patients is due to(i)a degenerative model in which the neurotoxic effect of an endogenous neurotoxin affects a single neuron,(ii)a neurotoxic event that is not expansive and(iii)the fact that the neurotoxin that triggers the neurodegenerative process is produced inside the neuromelanin-containing dopaminergic neurons.The endogenous neurotoxin that fits this degenerative model involving one single neuron at a time is aminochrome,since it(i)is generated within neuromelanin-containing dopaminergic neurons,(ii)does not cause an expansive neurotoxic effect and(iii)triggers all the mechanisms involved in the neurodegenerative process of the nigrostriata

关键词： 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine 6-hydroxydopamine aminochrome dopaminergic neurons DT-diaphorase exogenous neurotoxins glutathione transferase M2-2

Plant cell wall-mediated disease resistance:Current understanding and future perspectives

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Molecular Plant 2024年第5期17卷 699-724页

作者： Antonio Molina Lucıa Jorda Miguel Angel Torres Marina Martın-Dacal Diego Jose Berlanga Patricia Fernandez-Calvo Elena Gomez-Rubio Sonsoles Martın-Santamarıa Centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid(UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA/CSIC)Campus de Montegancedo UPMPozuelo de Alarcon(Madrid)Spain departamento de Biotecnologıa-Biología Vegetal Escuela Técnica Superior de Ingenierıa AgronomicaAlimentarıa y de BiosistemasUPMMadridSpain Centro de Investigaciones Biologicas Margarita Salas Consejo Superior de Investigaciones Científicas(CSIC)Ramiro de Maeztu 928040 MadridSpain Misión Biológica de Galicia Consejo Superior de Investigaciones Científicas(CSIC)Campus de Montegancedo UPMPozuelo de Alarcón(Madrid)Spain

Beyond their function as structural barriers,plant cell walls are essential elements for the adaptation of plants to environmental conditions.Cell walls are dynamic structures whose composition and integrity can be altered in response to environmental challenges and developmental cues.These wall changes are perceived by plant sensors/receptors to trigger adaptative responses during development and upon stress perception.Plant cell wall damage caused by pathogen infection,wounding,or other stresses leads to the release of wall molecules,such as carbohydrates(glycans),that function as damage-associated molecular patterns(DAMPs).DAMPs are perceived by the extracellular ectodomains(ECDs)of pattern recognition receptors(PRRs)to activate pattern-triggered immunity(PTI)and disease resistance.Similarly,glycans released from the walls and extracellular layers of microorganisms interacting with plants are recognized as microbe-associated molecular patterns(MAMPs)by specific ECD-PRRs triggering PTI responses.The number of oligosaccharides DAMPs/MAMPs identified that are perceived by plants has increased in recent years.However,the structural mechanisms underlying glycan recognition by plant PRRs remain limited.Currently,this knowledge is mainly focused on receptors of the LysM-PRR family,which are involved in the perception of various molecules,such as chitooligosaccharides from fungi and lipo-chitooligosaccharides(i.e.,Nod/MYC factors from bacteria and mycorrhiza,respectively)that trigger differential physiological responses.Nevertheless,additional families of plant PRRs have recently been implicated in oligosaccharide/polysaccharide recognition.These include receptor kinases(RKs)with leucine-rich repeat and Malectin domains in their ECDs(LRR-MAL RKs),Catharanthus roseus RECEPTOR-LIKE KINASE 1-LIKE group(CrRLK1L)with Malectin-like domains in their ECDs,as well as wall-associated kinases,lectin-RKs,and LRR-extensins.The characterization of structural basis of glycans recognition by these new plant receptors will shed light

关键词： Arabidopsis thaliana cell wall damage-associated molecular patterns DAMPs disease resistance glycans oligosaccharides pattern-triggered immunity PTl pattern recognition receptor PRRs

Hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： Boris I.Kharisov Oxana V.Kharissova Lucy T.González Yolanda Peña Méndez Igor E.Uflyand Idalia Gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico department of Chemistry Southern Federal UniversityRostov-on-DonRussia

Hydroxyapatite(HA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials chemistry.In particular,carbon allotropes are widely used in these composites being widely applied for medical purposes.Observing a gap of insufficient generalization of recent achievements in the field of the HA/Carbon composites,in this review we present the state of the art of the field of HA composites and hybrids with classic carbon allotropes and nanocarbons.These composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,etc.These composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among others.Combination of various synthesis techniques can be also carried out for composite preparation.Natural or synthetic HA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with HA directly or they can be first synthesized,in particular from biomass.Resulting biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic polymers.In these composites,especially with O-containing functionalizing groups,HA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial effect.GO→G reduction and higher HA decoration were observed in several experiments.The morphology of p

关键词： Hydroxyapatite Carbon nanotubes Graphene Quantum dots Fullerenes Nanodiamonds

Unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neuropathology and behavioral deficits in parkinsonian rats withα-synucleinopathy

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Neural Regeneration Research 2024年第9期19卷 2057-2067页

作者： Bismark Gatica-Garcia Michael J.Bannon Irma Alicia Martínez-Dávila Luis O.Soto-Rojas David Reyes-Corona Lourdes Escobedo Minerva Maldonado-Berny ME Gutierrez-Castillo Armando J.Espadas-Alvarez Manuel A.Fernandez-Parrilla Juan U.Mascotte-Cruz CP Rodríguez-Oviedo Irais E.Valenzuela-Arzeta Claudia Luna-Herrera Francisco E.Lopez-Salas Jaime Santoyo-Salazar Daniel Martinez-Fong departamento de Fisiología Biofísica y NeurocienciasCentro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico department of Pharmacology Wayne State University School of MedicineDetroitMIUSA Laboratorio de Patogénesis Molecular Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Red de Medicina para la Educación y desarrollo y la Investigación Científica de Iztacala(Red MEDICI) Carrera Médico CirujanoFacultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantla de BazMéxico Nanoparticle Therapy Institute AguascalientesMéxico departamento de Biociencias e Ingeniería Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y DesarrolloInstituto Politécnico NacionalCiudad de MéxicoMéxico escuela Nacional de Medicina y Homeopatía Instituto Politécnico NacionalCiudad de MéxicoMéxico departamento de Fisiología Escuela Nacional de Ciencias BiológicasInstituto Politécnico NacionalCiudad de MéxicoMéxico departamento de Biología Molecular y Biotecnología Instituto de Investigaciones BiomédicasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMéxico departamento de Física Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico Programa de Nanociencias y Nanotecnología Centro de Investigación y de Estudios AvanzadosCiudad de MéxicoMéxico

Parkinsonism by unilateral,intranigralβ-sitosterolβ-D-glucoside administration in rats is distinguished in that theα-synuclein insult begins unilaterally but spreads bilaterally and increases in severity over time,thus replicating several clinical features of Parkinson’s disease,a typicalα-synucleinopathy.As Nurr1 repressesα-synuclein,we evaluated whether unilateral transfected of rNurr1-V5 transgene via neurotensin-polyplex to the substantia nigra on day 30 after unilateralβ-sitosterolβ-D-glucoside lesion could affect bilateral neuropathology and sensorimotor deficits on day 30 post-transfection.This study found that rNurr1-V5 expression but not that of the green fluorescent protein(the negative control)reducedβ-sitosterolβ-D-glucoside-induced neuropathology.Accordingly,a bilateral increase in tyrosine hydroxylase-positive cells and arborization occurred in the substantia nigra and increased tyrosine hydroxylase-positive ramifications in the striatum.In addition,tyrosine hydroxylase-positive cells displayed less senescence markerβ-galactosidase and more neuron-cytoskeleton markerβIII-tubulin and brain-derived neurotrophic factor.A significant decrease in activated microglia(positive to ionized calcium-binding adaptor molecule 1)and neurotoxic astrocytes(positive to glial fibrillary acidic protein and complement component 3)and increased neurotrophic astrocytes(positive to glial fibrillary acidic protein and S100 calcium-binding protein A10)also occurred in the substantia nigra.These effects followed the bilateral reduction inα-synuclein aggregates in the nigrostriatal system,improving sensorimotor behavior.Our results show that unilateral rNurr1-V5 transgene expression in nigral dopaminergic neurons mitigates bilateral neurodegeneration(senescence and loss of neuron-cytoskeleton and tyrosine hydroxylase-positive cells),neuroinflammation(activated microglia,neurotoxic astrocytes),α-synuclein aggregation,and sensorimotor deficits.Increased neurotrophic astrocytes and brain-derived neurotrophic factor can mediate t

关键词： A1 astrocytes A2 astrocytes gene therapy microglia motor deficits nanoparticles neurodegeneration neuroinflammation senescence α-synuclein aggregates

Towards efficient strain engineering of 2D materials:A four-points bending approach for compressive strain

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Nano Research 2024年第6期17卷 5317-5325页

作者： Hao Li Félix Carrascoso Ana Borrás Gloria P.Moreno Francisco J.Aparicio Ángel Barranco Andrés Castellanos Gómez Campus de Cantoblanco Instituto de Ciencia de Materiales de MadridC.Sor Juana Inés de la Cruz328049 MadridSpain Nanotechnology on Surfaces and Plasma Lab Instituto de Ciencia de Materiales de Sevilla(CSIC-Universidad de Sevilla).C/Americo Vespucio 49E-41092 SevilleSpain departamento de Física Aplicada I Escuela Politécnica SuperiorUniversidad de Sevillac/Virgen deÁfrica 7E-41011 SevilleSpain

Strain engineering,as a powerful strategy to tune the optical and electrical properties of two-dimensional(2D)materials by deforming their crystal lattice,has attracted significant interest in recent years.2D materials can sustain ultra-high strains,even up to 10%,due to the lack of dangling bonds on their surface,making them ideal brittle solids.This remarkable mechanical resilience,together with a strong strain-tunable band structure,endows 2D materials with a broad optical and electrical response upon strain.However,strain engineering based on 2D materials is restricted by their nanoscale and strain quantification troubles.In this study,we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D materials.This approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation strategy.Our results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach.

关键词： uniaxial compressive strain polymer encapsulation differential reflectance spectroscopy exciton tunability

Exploring multifaceted factors in chronic kidney disease risk: A comprehensive analysis of biochemistry, lifestyle, and inflammation in elderly Chinese individuals

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World Journal of Clinical Cases 2024年第5期12卷 1033-1035页

作者： Fernando Cardona Unitat de Genètica Molecular Instituto de Biomedicina de Valencia–CSICValencia 46010Spain Centro de investigación Biomédica en Red Enfermedades Neurodegenerativas(CIBERNED) Instituto de Salud Carlos IIIMadrid 28029Spain departamento de Biotecnología Escuela Técnica Superior de Ingeniería Agronómica y del Medio Natural(ETSIAMN)Univeristat Politècnica de ValenciaValencia 46022Spain

This letter praises a recent article in the World Journal of Clinical Cases(Roles of biochemistry data,lifestyle,and inflammation in identifying abnormal renal function in old Chinese),examining factors affecting abnormal renal function in elderly Chinese using advanced machine learning.It highlights the importance of uric acid,age,hemoglobin,body mass index,sport hours,and systolic blood pressure.The study's holistic approach,integrating lifestyle and inflammation,offers a nuanced understanding of chronic kidney disease risk factors.The letter suggests exploring mechanistic pathways of hyperuricemia,the link between anemia and renal function,and the connection between body mass index and estimated glomerular filtration rate.It advocates investigating physical activity's impact on renal health and the independent effects of blood pressure.The study significantly contributes to chronic kidney disease understanding,proposing avenues for further exploration and interventions.Commendations are extended to the authors and the journal.

关键词： Biochemistry data Lifestyle Machine learning Renal function