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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

deep optics preconditioner for modulation-free pyramid wavefront sensing

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Photonics Research 2024年第2期12卷 301-312页

作者： FELIPE GUZMÁN JORGE TAPIA CAMILO WEINBERGER NICOLÁS HERNÁNdeZ JORGE BACCA BENOIT NEICHEL ESTEBAN VERA School of Electrical Engineering Pontificia Universidad Católica de Valparaı´soValparaı´soChile department of Systems Engineering Universidad Industrial de SantanderBucaramangaColombia Laboratoire d’Astrophysique de Marseille MarseilleFrance

The pyramid wavefront sensor(PWFS)can provide the sensitivity needed for demanding adaptive optics applications,such as imaging exoplanets using the future extremely large telescopes of over 30 m of diameter(D).However,its exquisite sensitivity has a limited linear range of operation,or dynamic range,although it can be extended through the use of beam modulation—despite sacrificing sensitivity and requiring additional optical hardware.Inspired by artificial intelligence techniques,this work proposes to train an optical layer—comprising a passive diffractive element placed at a conjugated Fourier plane of the pyramid prism—to boost the linear response of the pyramid sensor without the need for cumbersome modulation.We develop an end-2-end simulation to train the diffractive element,which acts as an optical preconditioner to the traditional least-square modal phase estimation process.Simulation results with a large range of turbulence conditions show a noticeable improvement in the aberration estimation performance equivalent to over 3λ∕D of modulation when using the optically preconditioned deep PWFS(DPWFS).Experimental results validate the advantages of using the designed optical layer,where the DPWFS can pair the performance of a traditional PWFS with 2λ∕D of modulation.designing and adding an optical preconditioner to the PWFS is just the tip of the iceberg,since the proposed deep optics methodology can be used for the design of a completely new generation of wavefront sensors that can better fit the demands of sophisticated adaptive optics applications such as ground-to-space and underwater optical communications and imaging through scattering media.

关键词： process optics pyramid

Ventriculo-atrial shunt with occlusion of the internal jugular vein: operative experience and surgical technique

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中华神经外科杂志(英文) 2024年第2期10卷 1-8页

作者： Quintero Silvia Tatiana Ramirez-Velandia Felipe Moreno Andres Felipe Hortua Vera Lina Rugeles Paula Gonzalez Rafael Augusto Azuero Pontificia universidad Javeriana Clinica Medilaser S.A.S. Clinica Chicamocha Bucaramanga Santander Colombia Neurology and Neurosurgery Research Group Pontificia Universidad Javeriana Bogotá D.C. Colombia universidad industrial de santander Clinica Chicamocha Bucaramanga Colombia universidad Autónoma de Bucaramanga Clinica Chicamocha Bucaramanga Colombia Clinica Chicamocha Bucaramanga Santander Colombia

Background Ventricular shunts are one of the most frequent techniques used for the management of hydrocephalus. The ventriculoperitoneal shunt (VPS) is the most commonly performed procedure, and the ventriculoatrial shunt (VAS) is the second option in most medical centers. The main objective of this study is to introduce and describe a surgical approach for VAS outlining our experience and comparing it with traditional shunting techniques.Methods In this retrospective cohort comparison study, we included patients with hydrocephalus treated with a surgical procedure between January 2010 and February 2021 at a single academic institution. We categorized the procedures into two groups: patients with VPS and conventional VAS grouped together into the conventional technique (CT) group, and the second group was patients with whom we performed VAS with complete internal jugular vein occlusion (IJVOT). We compared the surgical time, postoperative complications, and occurrence of shunt failure among the groups by performing univariate analysis using the Fisher exact test.Results Out of the 106 patients included in the analysis, IJVOT was performed in 66 patients, and CT in 40 patients. The median surgical time was 60 min (IQR 60-90) for IJVOT versus 100 min (IQR 60-120) for CT (p demonstrate that VAS with IJVOT is a safe method that exhibited shorter surgical times and outcomes comparable to CT. However, since the present study represents the first cohort evaluating IJVOT, it is imperative to conduct larger prospective studies, along with clinical trials, to fully explore and establish efficacy, long-term outcomes, and an in-depth comparison among shunting techniques.

关键词： Hydrocephalus Ventriculoatrial shunting Internal jugular vein Operative time Complications Shunt removal

Genetic and epigenetic targets of natural dietary compounds as anti-Alzheimer's agents

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Neural Regeneration Research 2024年第4期19卷 846-854页

作者： Willian Orlando Castillo-Ordoñez Nohelia Cajas-Salazar Mayra Alejandra Velasco-Reyes Facultad de Ciencias Naturales-Exactas y de la Educación Departamento de Biología.Universidad del Cauca departamento de Estudios Psicológicos Universidad Icesi

Alzheimer’s disease is a progressive neurodegenerative disorder and the most common cause of dementia that principally affects older adults.Pathogenic factors,such as oxidative stress,an increase in acetylcholinesterase activity,mitochondrial dysfunction,genotoxicity,and neuroinflammation are present in this syndrome,which leads to neurodegeneration.Neurodegenerative pathologies such as Alzheimer’s disease are considered late-onset diseases caused by the complex combination of genetic,epigenetic,and environmental factors.There are two main types of Alzheimer’s disease,known as familial Alzheimer’s disease(onsetdelian anomalies suggesting an epigenetic component in its etiology.Importantly,the fundamental pathophysiological mechanisms driving Alzheimer’s disease are interfaced with epigenetic dysregulation.However,the dynamic nature of epigenetics seems to open up new avenues and hope in regenerative neurogenesis to improve brain repair in Alzheimer’s disease or following injury or stroke in humans.In recent years,there has been an increase in interest in using natural products for the treatment of neurodegenerative illnesses such as Alzheimer’s disease.Through epigenetic mechanisms,such as DNA methylation,non-coding RNAs,histone modification,and chromatin conformation regulation,natural compounds appear to exert neuroprotective effects.While we do not purport to cover every in this work,we do attempt to illustrate how various phytochemical compounds regulate the epigenetic effects of a few Alzheimer’s disease-related genes.

关键词： Alzheimer’s disease epigenetics genes methylation natural products

Common interacting genetic variation shapes susceptibility to type 1 diabetes in a Colombian Caribbean community:In search of shared genetic markers

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Genes & Diseases 2024年第4期11卷 106-108页

作者： Gloria Garavito-de Egea Alex Dominguez-Vargas Jorg e l.Velez Gustavo Aroca Luis Fagng Elkin Navarro-Quiroz Zilac Espitaleta Kenny del Toro-Camargo Leticia Martinez-Ariza Tatiana Gonzalez-Vargas Susana Garcia Mauricio Arcos-Burgos Eduardo Egea universidad del Norte Division Ciencias de la SaludBarranquillaColombia universidad Simon Bolivar Facultad de Ciencias de la SaludBarranquillaColombia Clinica de la Costa Grupo de Investigacion en NefrologiaBarranquillaColombia universidad de Antioquia Grupo de Investigacion en Psiquiatria(GIPSI)Departamento de PsiquiatriaInstituto de Investigaciones MedicasFacultad de MedicinaMedellinColombia

Genome-wide association studies(GWASs)have identified hundreds of loci across the human genome conferring susceptibility to autoimmune diseases(AIDs),some of which are shared between more than two diseases.However,thi... 详细信息

关键词： susceptibility diseases diabetes

Empagliflozin reduces brain pathology in Alzheimer's disease and type 2 diabetes

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Neural Regeneration Research 2024年第6期19卷 1189-1190页

作者： Carmen Hierro-Bujalance Monica Garcia-Alloza Division of Physiology School of MedicineUniversidad de Cadiz Instituto de Investigacion e Innovacion en Ciencias Biomedicas de la Provincia de Cadiz (INIBICA) Salus Infirmorum-universidad de Cadiz

Alzheimer’s disease(AD) and type 2 diabetes(T2D): More than 55 million people suffer from dementia, and it is expected that over 150 million people will suffer from this disease by 2050. AD is the most common type of dementia and while aging remains the main risk factor to suffer it, previous studies have also shown that metabolic disorders, and T2D specifically, are also major contributors(Wang et al., 2012).

关键词： INHIBITORS

Presynaptic endoplasmic reticulum architecture and hereditary spastic paraplegia

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Neural Regeneration Research 2024年第3期19卷 485-486页

作者： Juan JoséPérez-Moreno Instituto de Biomedicina de Sevilla(IBiS) Hospital Universitario Virgen Del Rocío/CSIC/Universidad de Sevillaand Departamento de Biología CelularFacultad de BiologíaUniversidad de SevillaSevilleSpain

Hereditary spastic paraplegia(HSP)is a clinically and genetically heterogeneous neurodegenerative disorder,characterized primarily by progressive spasticity and weakness in the lower limbs.Pat ients can also experience peripheral neuropathy,cognitive impairment,and other neurological symptoms.To date,more than 80 genes have been implicated in HSP,encompassing various cellular components,although mutations in genes encoding endoplasmic reticulum(ER)-shaping proteins are the most prevalent(Parodi et al.,2017).ER-shaping proteins are generally known for regulating the tubulation and curvation of the ER,but most of them show additional functions,including fusion of ER tubules,microtubule-severing,ER autophagy,lipid droplet synthesis,contact sites with other organelles(Öztürk et al.,2020).This highlights the complexity of studying the role of these proteins and the link between ER function and HSP.

关键词： reticulum endoplasmic

A prototype for on-site generation of chlorinated disinfectant for use in rural aqueducts

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Water Science and Engineering 2024年第1期17卷 33-40页

作者： Diana Marcela Cuesta Parra Felipe Correa Mahecha Andrés Felipe Rubio Pinzon Davidcamilo Ramirez Bustos Leonel Alveyro Teran Llorente Miguel Fernando Jimenez Jimenez Chemical and Environmental Engineering department Fundacion Universidad de AmericaBogota 11711Colombia Chemical Engineering department Fundacion Universidad de AmericaBogota 117111Colombia Mecanical Engineering department Fundacion Universidad de AmericaBogota 117111Colombia

Sodium hypochlorite has significant potential as a sanitation solution in hard-to-reach areas.Few studies have investigated the optimal electrolysis parameters for its production with volumes greater than 1o L.This study evaluated sodium hypochlorite production through electrolysis in a 22-L prototype and identified the optimal operating parameters.Tests were performed using graphite electrodes with areas of 68.4 cm²at the laboratory scale and 1865.0 cm?at the prototype scale.A design for experiments with different operating times,chloride concentrations,and electric current intensities was developed.The optimal operating time,sodium chloride concentration,and current intensity at the laboratory scale were 120 min,150 g of chloride per liter,and 3 A,respectively,leading to the production of 5.02 g/L of the disinfectant with an energy efficiency of 12.21 mg of Cl2 per kilojoule.At the prototype scale,the maximum sodium hypochlorite concentration of 3.99 g of chloride per liter was achieved with an operating time of 120 min,a sodium chloride concentration of 100 g of chloride per liter,and a current intensity of 70 A,reaching an energy efficiency of 42.56 mg of Cl2 per kilojoule.In addition,this study evaluated the influences of the chloride concentration,current intensity,and operating time on the production of sodium hypochlorite at the two scales,and formulated the equations showing the trends of sodium hypochlorite production and energy efficiency in the electrochemical systems.The 22-L prototype model for production of this oxidizing substance is promising for disinfection of large volumes of water in areas that are difficult to access.

关键词： Disinfection Electrolysis Energy efficiency Optimization Sodium hypochlorite

DNA metabarcoding reveals seasonal changes in diet composition across four arthropod-eating lizard species(Phrynosomatidae:Sceloporus)

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Integrative Zoology 2024年第3期19卷 480-495页

作者： Mauricio HERNÁNdeZ Stephanie HEREIRA-PACHECO Antton ALBERDI Aníbal H.DÍAZ de LA VEGA-PÉREZ Arturo ESTRADA-TORRES Sergio ANCONA Yendi E.NAVARRO-NOYA Doctorado en Ciencias Biológicas Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Estación Científica La Malinche Centro Tlaxcala de Biología de la ConductaUniversidad Autónoma de TlaxcalaTlaxcalaMexico Center for Evolutionary Hologenomics The Globe InstituteUniversity of CopenhagenCopenhagenDenmark Consejo Nacional de Ciencia y Tecnología-Centro Tlaxcala de Biología de la Conducta Universidad Autónoma de TlaxcalaTlaxcalaMexico departamento de Ecología Evolutiva Instituto de EcologíaUniversidad Nacional Autónoma de MéxicoMexico CityMexico Laboratorio de Interacciones Bióticas Centro de Investigación en Ciencias BiológicasUniversidad Autónoma de TlaxcalaSan Felipe IxtacuixtlaTlaxcalaMexico

Diet composition and its ecological drivers are rarely investigated in coexisting closely related species.We used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous ecosystem.DNA metabarcoding revealed that the lizards Sceloporus aeneus,S.bicanthalis,S.grammicus,and S.spinosus mostly consumed arthropods of the orders Hemiptera,Araneae,Hymenoptera,and Coleoptera.The terrestrial lizards S.aeneus and S.bicanthalis mostly predated ants and spiders,whereas the arboreal–saxicolous S.grammicus and saxicolous S.spinosus largely consumed grasshoppers and leafhoppers.The taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season,likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional demands.Dietary and phylogenetic composition varied seasonally depending on the species,but only dietary composition varied with altitude.Seasonal dietary turnover was greater in S.spinosus than in S.bicanthalis,suggesting site-specific seasonal variability in prey availability;no other differences among species were observed.S.bicanthalis,which lives at the highest altitude in our study site,displayed interseasonal variation in diet breadth.Dietary differences were correlated with the species’feeding strategies and elevational distribution,which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.

关键词： arthropod-eating lizards diet breadth environmental barcoding mountainous ecosystem seasonal dietary shifts