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Fetkin-hydro,a new thermo-hydrological algorithm for low-temperature thermochronological modeling

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Geoscience Frontiers 2021年第3期12卷 186-200页

作者： francisco sánchez Andres Barrea Federico M.Dávila Andres Mora Centro de Investigaciones en Ciencias de la Tierra(CICTERRA) CONICET-UNCFCEFyNCiudad UniversitariaAv.Vélez Sarsfield 16115000 CórdobaArgentina Facultad de Matemática AstronomíaFísica y Computación(FAMAF)Ciudad UniversitariaAv.Medida Allende 21445000 CórdobaArgentina Ecopetrol BotafogoRio de JaneiroBrazil

Despite two decades of major advances in the field of thermochronological modeling,state-of-the-art numerical implementations still rely mostly on burial and exhumation processes to explain radiometric *** though such an approach has proved valuable,failing to account for other first-order geological variables has led to misinterpretations and therefore,calls for a *** this study a new version of the Fetkin(finite element temperature kinematics,Ecopetrol)program is *** new algorithm couples time-dependent hydrological and thermal calculations,thus rendering thermochronological ages that,instead of being solely dependent on the kinematical evolution of a system,conditioning by the fluid flow is also *** contrast with previous thermochronological models,this work considers the influence of effective stress on rock properties(porosity and permeability)and therefore,in thermal *** analyses addressing relevant geological questions show not only the versatility of the code but also,new perspectives on forward low-temperature thermochronological *** circulation through pure-sandstone settings produce colder thermal architectures than those obtained in impermeable *** in cooling ages from models with and without fluid circulation are up to 5 Myr.A 4-fold variation in thrusting rates(0.5 km/Myr to 2 km/Myr)produces a 15-Myr difference in cooling ages in models with fluid flow,which contrasts to much lower differences,only 2 Myr,in domains without(or minimal)fluid circulation.2D thermal solutions in fold-bend-fold thrust belts composed of sandstones remain static despite substantial relief development by kinematic folding.A case-study from Western Argentina,in the Andean Precordillera,confirms the plausibility of the numerical algorithm here posed and raises new questions on the first-order thermal controls in settings under deformation.

关键词： Thermochronology Hydrogeology Fluid flow Numerical modeling

Animal models used to study direct peripheral nerve repair: a systematic review

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Neural Regeneration Research 2020年第3期15卷 491-502页

作者： francisco Javier Vela Guadalupe Martínez-Chacón Alberto Ballestín JoséLuis Campos francisco Miguel sánchez-Margallo Elena Abellán Department of Microsurgery Jesús Usón Minimally Invasive Surgery CentreCáceresSpain scientific Director Jesús Usón Minimally Invasive Surgery CentreCáceresSpain

Objective:Peripheral nerve repair is required after traumatic *** common condition represents a major public health problem *** after nerve repair depends on several factors,including the severity of the injury,the nerve involved,and the surgeon’s technical *** the precise microsurgical repair of nerve lesions,adequate functional recovery is not always achieved and,therefore,the regeneration process and surgical techniques are still being ***-clinical animal models are essential for this research and,for this reason,the focus of the present systematic review(according to the PRIsMA statement)was to analyze the different animal models used in pre-clinical peripheral nerve repair *** sources:Original articles,published in English from 2000 to 2018,were collected using the Web of science,scopus,and PubMed *** selection:Only preclinical trials on direct nerve repair were included in this *** articles were evaluated by the first two authors,in accordance with predefined data *** measures:The primary outcomes included functional motor abilities,daily activity and regeneration *** outcomes included coaptation technique and animal ***:This review yielded 267 articles,of which,after completion of the screening,49 studies were *** were 1425 animals in those 49 studies,being rats,mice,guinea pigs,rabbits,cats and dogs the different pre-clinical *** nerves used were classified into three groups:head and neck(11),forelimb(8)and hindlimb(30).The techniques used to perform the coaptation were:microsuture(46),glue(12),laser(8)and mechanical(2).The follow-up examinations were histology(43),electrophysiological analysis(24)and behavioral observation(22).Conclusion:The most widely used animal model in the study of peripheral nerve repair is the *** animal models are also used but the cost-benefit of the rat model provides several strengths over the ***

关键词： nerve microsurgery peripheral nerve regeneration repair reconstruction direct nerve repair animal model coaptation PRIsMA systematic review

An approximate Kerr-Newman-like metric endowed with a magnetic dipole and mass quadrupole

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Communications in Theoretical Physics 2024年第8期76卷 124-138页

作者： francisco Frutos-Alfaro space Research Center and school of Physics University of Costa RicaSan PedroSan JoseCosta Rica

Approximate all-terrain spacetimes for astrophysical applications are presented. The metrics possess five relativistic multipole moments, namely, mass, rotation, mass quadrupole, charge,and magnetic dipole moment. All these spacetimes approximately satisfy the Einstein-Maxwell field equations. The first metric is generated using the Hoenselaers-Perjés method from given relativistic multipoles. The second metric is a perturbation of the Kerr-Newman metric, which makes it a relevant approximation for astrophysical calculations. The last metric is an extension of the Hartle-Thorne metric that is important for obtaining internal models of compact objects perturbatively. The electromagnetic field is calculated using Cartan forms for locally non-rotating observers. These spacetimes are relevant for inferring properties of compact objects from astrophysical observations. Furthermore, the numerical implementations of these metrics are straightforward, making them versatile for simulating potential astrophysical applications.

关键词： Gravitation Einstein-Maxwell equations Compact objects

A wood-wood joining system suitable for digital fabrication and its application in the design of a“wood-only”spatial modulea

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Frontiers of Architectural Research 2023年第3期12卷 523-540页

作者： Antonio Jesús de-los-Aires-solís francisco Gonzalez-Quintial Doctoral school.University of the Basque Country UPV/EHULeioa 48940Spain Department of Architecture.University of the Basque Country UPV/EHULeioa 48940Spain

This paper describes a wood-wood spatial joining system adapted to digital fabrication which has been designated the“spatial Masterkey”.The wood stereotomy of the joints between the different pieces that make up this joining system is inspired by a three-dimensional puzzle called“snowflake”.The production process used in the masterkey system can be carried out using only a 3-axis CNC milling machine—a relatively affordable and easily accessible *** using digital manufacturing for the execution of wood-wood joints,several benefits are obtained including faster machining and greater cutting precision and uniformity in the products *** advantages make this joining system both economically competitive and environmentally ***,the versatility of this joining system means that its configuration can be adapted to a wide range of casuistry of encounters between members,which means that it can be used for a number of spatial *** includes,but is not limited to,the spatial module presented in this document.

关键词： Wood-wood joinery Digital fabrication 3-Axis CNC spatial module sustainability Burr puzzle

In search for the “idyllic” animal model to evaluate ocular pathologies and translate new therapies to improve human health

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Neural Regeneration Research 2022年第12期17卷 2697-2699页

作者： francisco M.Nadal-Nicolás Kiyoharu J.Miyagishima Wei Li Retinal Neurophysiology section National Eye InstituteNational Institutes of HealthBethesdaMDUSA

The retina is a highly specialized neural tissue that encodes information of vision,a vital sensory modality for most *** the retina also contributes to other non‐image‐forming signals(*** of circadian clocks),vision chiefly enables animals to interpret and navigate their environment(despite the diverse variety of species and lifestyles;Baden et al.,2020)and also to interact with other ***,features such as high visual resolution and color discrimination are important for interactive behaviors like prey capture and also for social animals,including primates,that establish a dominance *** vertebrates,the laminar structure of the retina is notably *** photoreceptor layer(rods and cones)initiates the process of converting light energy into nerve impulses by absorbing photons and transferring the signals to interneurons.

关键词： laminar enable absorbing

Adenosine A1 receptor ligands bind toα-synuclein:implications forα-synuclein misfolding andα-synucleinopathy in Parkinson’s disease

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Translational Neurodegeneration 2022年第1期11卷 809-834页

作者： Elisabet Jakova Mohamed Taha Moutaoufik Jeremy s.Lee Mohan Babu francisco s.Cayabyab Department of surgery College of MedicineUniversity of SaskatchewanSaskatoonSKCanada Department of Chemistry and Biochemistry Faculty of ScienceUniversity of ReginaReginaSKCanada Department of Biochemistry Microbiology and ImmunologyCollege of MedicineUniversity of SaskatchewanSaskatoonSKCanada.

Background:Accumulatingα-synuclein(α-syn)aggregates in neurons and glial cells are the staples of many synucleinopathy disorders,such as Parkinson’s disease(PD).since brain adenosine becomes greatly elevated in ageing brains and chronic adenosine A1 receptor(A1R)stimulation leads to neurodegeneration,we determined whether adenosine or A1R receptor ligands mimic the action of known compounds that promoteα-syn aggregation(e.g.,the amphetamine analogue 2-aminoindan)or inhibitα-syn aggregation(e.g.,Rasagiline metabolite 1-aminoindan).In the present study,we determined whether adenosine,A1R receptor agonist N^(6)-Cyclopentyladenosine(CPA)and antago-nist 8-cyclopentyl-1,3-dipropylxanthine(DPCPX)could directly interact withα-syn to modulateα-syn aggregation and neurodegeneration of dopaminergic neurons in the substantia nigra(sN).Methods:Nanopore analysis and molecular docking were used to test the binding properties of CPA and DPCPX withα-syn in ***-Dawley rats were administered with 7-day intraperitoneal injections of the A1R ligands and 1-and 2-aminoindan,and levels ofα-syn aggregation and neurodegeneration were examined in the sN pars compacta and hippocampal regions using confocal imaging and Western ***:Using nanopore analysis,we showed that the A1R agonists(CPA and adenosine)interacted with the N-terminus ofα-syn,similar to 2-aminoindan,which is expected to promote a“knot”conformation andα-syn *** contrast,the A1R antagonist DPCPX interacted with the N-and C-termini ofα-syn,similar to 1-aminoindan,which is expected to promote a“loop”conformation that preventsα-syn *** docking studies revealed that adenosine,CPA and 2-aminoindan interacted with the hydrophobic core ofα-syn N-terminus,whereas DPCPX and 1-aminoindan showed direct binding to the N-and C-terminal hydrophobic *** imaging and Western blot analyses revealed that chronic treatments with CPA alone or in combination with 2-aminoindan increasedα-syn

关键词： Alpha-synucleinopathy Adenosine A1 receptor N6-cyclopentyladenosine 8-cyclopentyl-1 3-dipropylxanthine 1-aminoindan 2-aminoindan Neuroprotection Neurodegeneration Protein misfolding

Resveratrol attenuates metabolic,sperm,and testicular changes in adult Wistar rats fed a diet rich in lipids and simple carbohydrates

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Asian Journal of Andrology 2019年第2期21卷 201-207页

作者： Fabiana A de Oliveira Waldemar s Costa francisco J B sampaio Bianca M Gregorio Urogenital Research Unit Biomedical CenterState University of Rio de JaneiroRio de Janeiro 20551-030Brazil

High-fat diets affect male reproduction and sexual ***,we evaluated the effects of prolonged resveratrol administration on the metabolic,sperm,and testicular parameters of rats fed a cafeteria *** Wistar rats were divided at weaning into control(Cv n=20)and cafeteria(CAF,n=16)*** 3 months,half of them were given daily supplementations of resveratrol(C-R,n=10;CAF-R,n=8)at a dosage of 30 mg kg-1 body mass for 2 *** were killed at 5 months of age,and blood,spermatozoa,and testes were collected for further *** were analyzed by one-way ANOVA,and Ps considered statistically *** CAF diet promoted hyperglycemia(Psveratrol reversed this condition(Psperm viability and motility,while resveratrol improved these parameters(Fsticular morphology,the height of the seminiferous epithelium was reduced in the CAF group compared with that of the C group(P=0.0007).spermatogenic cell proliferation was also reduced in the CAF group compared with that of the C ***,the CAF-R showed an increase in cell proliferation rate compared with that of the untreated CAF group(P=0.0024).Although it did not modify body mass,the consumption of a CAF diet promoted hyperglycemia,adverse testicular morphology remodeling,and abnormal sperm,which were attenuated by treatment with resveratrol,thus suggesting a protective effect of this antioxidant on spermatogenesis.

关键词： cafeteria diet morphology resveratrol spermatozoa testicle

CpG island methylator phenotype in adenocarcinomas from the digestive tract:Methods,conclusions,and controversies

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World Journal of Gastrointestinal Oncology 2017年第3期9卷 105-120页

作者： francisco sánchez-Vega Valer Gotea Yun-Ching Chen Laura Elnitski Genomic Functional Analysis section National Human Genome Research InstituteNational Institutes of HealthRockvilleMD 20852United States

Over the last two decades, cancer-related alterations in DNA methylation that regulate transcription have been reported for a variety of tumors of the gastrointestinal tract. Due to its relevance for translational research, great emphasis has been placed on the analysis and molecular characterization of the CpG island methylator phenotype(CIMP), defined as widespread hypermethylation of CpG islands in clinically distinct subsets of cancer patients. Here, we present an overview of previous work in this field and also explore some open questions using crossplatform data for esophageal, gastric, and colorectal adenocarcinomas from The Cancer Genome Atlas. We provide a data-driven, pan-gastrointestinal stratification of individual samples based on CIMP status and we investigate correlations with oncogenic alterations, including somatic mutations and epigenetic silencing of tumor suppressor genes. Besides known events in CIMP such as BRAF V600 E mutation, CDKN2 A silencing or MLH1 inactivation, we discuss the potential role of emerging actors such as Wnt pathway deregulation through truncating mutations in RNF43 and epigenetic silencing of WIF1. Our results highlight the existence of molecular similarities that are superimposed over a larger backbone of tissue-specific features and can be exploited to reduce heterogeneity of response in clinical trials.

关键词： CpG island methylator phenotype CpG island Promoter DNA methylation Hypermethylation Gastrointestinal cancer

Lessons from glaucoma: rethinking the fluid-brain barriers in common neurodegenerative disorders

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Neural Regeneration Research 2019年第6期14卷 962-966页

作者： francisco Javier Carreras Department of surgery Faculty of MedicineUniversity of Granada

Glaucoma has been recently characterized as a member of the group of anoikis-related diseases. Anoikis, a form of apoptosis, can be triggered by the unfastening of adherent junctions present in astrocytes. In those areas of the central nervous system in which the soma of the neurons or their axons and dendrites are metabolically dependent on the activity of astrocytes, a derangement of the lactate shuttle caused by a separation between the plasma membranes of neurons and astrocytes would result in metabolic impairment of the neurons themselves. In glaucoma, the triggering event has been attributed to the posterior deviation of aqueous humor towards the astrocyte-rich prelaminar tissue of the optic nerve head. The mean calcium content in the aqueous is able to interfere with calcium-dependent adherent junctions and induce anoikis of the astrocytes. As the cerebrospinal fluid has a similar base calcium concentration, a shunt of cerebrospinal fluid through the cerebral parenchyma would be able to interfere in the astrocytic architecture with dire consequences to the metabolically dependent neurons. Here the similitude between glaucoma,amyotrophic lateral sclerosis and Alzheimer's disease are discussed and the concept of the break in the fluid-brain barrier, as an event separated from the blood-brain barrier, is stressed.

关键词： fluid-brain barriers blood-brain barrier cerebrospinal fluid aqueous humor calcium ion glaucoma amyotrophic lateral sclerosis Alzheimer’s disease