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Preliminary examination of early neuroconnectivity features in the R6/1 mouse model of Huntington's disease by ultra-high field diffusion MRI

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Neural Regeneration Research 2022年第5期17卷 983-986页

作者： rodolfo g.gatto Carina Weissmann Department of Bioengineering the University of Illinois at ChicagoChicagoILUSA Instituto de Fisiología Biología Molecular y Neurociencias-IFIBYNECONICET Universidad de Buenos AiresBuenos AiresArgentina

During the last decades,advances in the understanding of genetic,cellular,and microstructural alterations associated to Huntington's disease(HD)have improved the understanding of this progressive and fatal ***,events related to early neuropathological events,neuroinflammation,deterioration of neuronal connectivity and compensatory mechanisms still remain vastly ***-high field diffusion MRI(UHFD-MRI)techniques can contribute to a more comprehensive analysis of the early microstructural changes observed in *** addition,it is possible to evaluate if early imaging microstructural parameters might be linked to histological ***,qualitative studies analyzing histological complexity in brain areas susceptible to neurodegeneration could provide information on inflammatory events,compensatory increase of neuroconnectivity and mechanisms of brain repair and *** application of ultra-high field diffusion-MRI technology in animal models,particularly the R6/1 mice(a common preclinical mammalian model of HD),provide the opportunity to analyze alterations in a physiologically intact model of the *** some disparities in volumetric changes across different brain structures between preclinical and clinical models has been documented,further application of different diffusion MRI techniques used in combination like diffusion tensor imaging,and neurite orientation dispersion and density imaging have proved effective in characterizing early parameters associated to alteration in water diffusion exchange within intracellular and extracellular compartments in brain white and grey ***,the combination of diffusion MRI imaging techniques and more complex neuropathological analysis could accelerate the discovery of new imaging biomarkers and the early diagnosis and neuromonitoring of patients affected with HD.

关键词： brain repair diffusion tensor imaging Huntington's disease neurite orientation dispersion and density imaging neuroconnectivity neuroinflammation neuroplasticity neuroregeneration R6/1 mice ultra-high field diffusion MRI

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Assessing neuraxial microstructural changes in a transgenic mouse model of early stage Amyotrophic Lateral Sclerosis by ultra-high field MRI and diffusion tensor metrics

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Animal Models and Experimental Medicine 2020年第2期3卷 117-129页

作者： rodolfo g.gatto Carina Weissmann Manish Amin Ariel Finkielsztein Ronen Sumagin Thomas H.Mareci Osvaldo D.Uchitel Richard L.Magin Department of Bioengineering University of Illinois at ChicagoChicagoILUSA Instituto de Fisiología Biologia Molecular y Neurociencias-IFIBYNE-CONICET University of Buenos AiresBuenos AiresArgentina Department of Biochemistry National High Magnetic Field LaboratoryUniversity of FloridaGainesvilleFLUSA Department of Pathology School of MedicineNorthwestern UniversityChicagoILUSA

Objective: Cell structural changes are one of the main features observed during the development of amyotrophic lateral sclerosis(ALS). In this work, we propose the use of diffusion tensor imaging(DTI) metrics to assess specific ultrastructural changes in the central nervous system during the early neurodegenerative stages of ***: Ultra-high field MRI and DTI data at 17.6 T were obtained from fixed, excised mouse brains, and spinal cords from ALS(g93 A-SOD1) ***: Changes in fractional anisotropy(FA) and linear, planar, and spherical anisotropy ratios(C_L, C_P, and C_S, respectively) of the diffusion eigenvalues were measured in white matter(WM) and gray matter(gM) areas associated with early axonal degenerative processes(in both the brain and the spinal cord). Specifically, in WM structures(corpus callosum, corticospinal tract, and spinal cord funiculi) as the disease progressed, FA, C_L, and C_P values decreased, whereas C_S values increased. In gM structures(prefrontal cortex, hippocampus, and central spinal cord) FA and C_P decreased, whereas the C_L and C_S values were unchanged or slightly smaller. Histological studies of a fluorescent mice model(YFP, g93 A-SOD1 mouse) corroborated the early alterations in neuronal morphology and axonal connectivity measured by ***: Changes in diffusion tensor shape were observed in this animal model at the early, nonsymptomatic stages of ALS. Further studies of C_L, C_P, and C_S as imaging biomarkers should be undertaken to refine this neuroimaging tool for future clinical use in the detection of the early stages of ALS.

关键词： amyotrophic lateral sclerosis animal models diffusion tensor imaging g93A-SOD1 mice ultra-high field MRI

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Ultra-High Field Diffusion MRI Reveals Early Axonal Pathology in Spinal Cord of ALS mice

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Translational Neurodegeneration 2018年第1期7卷 187-200页

作者： rodolfo g.gatto Manish Y.Amin Daniel Deyoung Matthew Hey Thomas H.Mareci Richard L.Magin Department of Anatomy and Cell Biology University of Illinois at Chicago808 S.Wood St.Rm 578 M/C 512ChicagoIL 60612USA Department of Physics University of FloridaGainesvilleFLUSA Department of Applied Physiology and Kinesiology University of FloridaGainesvilleFLUSA Department of Biochemistry and Molecular Biology University of FloridaGainesvilleFLUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Background:Amyotrophic lateral sclerosis(ALS)is a disease characterized by a progressive degeneration of motor neurons leading to *** previous MRI diffusion tensor imaging studies detected early white matter changes in the spinal cords of mice carrying the g93A-SOD1 ***,we extend those studies using ultra-high field MRI(17.6 T)and fluorescent microscopy to investigate the appearance of early structural and connectivity changes in the spinal cords of ALS ***:The spinal cords from presymptomatic and symptomatic mice(80 to 120 days of age)were scanned(ex-vivo)using diffusion-weighted *** fractional anisotropy(FA),axial(AD)and radial(RD)diffusivities were calculated for axial slices from the thoracic,cervical and lumbar regions of the spinal *** diffusion parameters were compared with fluorescence microscopy and membrane cellular markers from the same tissue ***:At early stages of the disease(day 80)in the lumbar region,we found,a 19% decrease in FA,a 9% decrease in AD and a 35% increase in *** changes were observed in cervical and thoracic spinal cord *** between control and ALS mice groups at the symptomatic stages(day 120)were *** fluorescence microscopy at 80 days,demonstrated a 22% reduction in axonal area and a 22% increase in axonal *** and quantitative connectome analyses measured by edge weights showed a 52%decrease in the lumbar regions of the spinal cords of this ALS mice group.A significant increase in ADC(23.3%)in the ALS mice group was related to an increase in aquaporin ***:These findings suggest that the combination of ultra-high field diffusion MRI with fluorescent ALS mice reporters is a useful approach to detect and characterize presymptomatic white matter micro-ultrastructural changes and axonal connectivity anomalies in ALS.

关键词： Amyotrophic Lateral Sclerosis Spinal Cord,Ultra-high Field MRI Diffusion Tensor Imaging Yellow Fluorescent Protein g93A-SOD1 mice Axonal Degeneration Tractography Connectomics

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A Review of Basic Mechanical Properties of Bamboo Scrimber Based on Small-Scale Specimens

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Journal of Renewable Materials 2024年第4期12卷 869-894页

作者： Xin Xue Haitao Li rodolfo Lorenzo College of Civil Engineering Nanjing Forestry UniversityNanjing210037China National-Provincial Joint Engineering Research Center of Biomaterials for MACHINERY PACKAgE Nanjing Forestry UniversityNanjing210037China Jiangsu Engineering Research Center of Bamboo and Wood Carbon FixationMaterials and Structures Nanjing Forestry UniversityNanjing210037China Department of Civil Environmental and Geomatic EngineeringUniversity College LondonLondonWC1E 6BTUK

This review summarizes the existing knowledge about the mechanical properties of bamboo scrimber(BS)in *** to literature reviews,the strength of BS under different load modes is affected by a series of factors,such as the type of original bamboo,growth position,resin content,treatment method and ***,different production processes can be adopted according to different requirements,and bamboo scrimbers can also be classified *** addition,this review summarizes the changes in different factors considered by scholars in the research on the mechanical properties of BS,so that readers can have an overall understanding of the existing research and make more innovative and valuable research on this *** review provides and discusses the conclusive observations,the current research gaps and future research directions on the mechanical properties of BS.

关键词： Bamboo scrimber manufacturing process mechanical properties failure modes constitutive model

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Diffusion tensor imaging as a tool to detect presymptomatic axonal degeneration in a preclinical spinal cord model of amyotrophic lateral sclerosis

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Neural Regeneration Research 2018年第3期13卷 425-426页

作者： rodolfo gabriel gatto Department of Anatomy and Cell Biology University of Illinois at Chicago

The g93A-SOD1 mice model and MRI diffusion as a preclinical tool to study amyotrophic lateral sclerosis （ALS）： ALS is a progressive neurological disease characterized primarily by the development of limb paralysis, which eventually leads to lack of control on muscles under voluntary control and death within 3–5 years. genetic heterogeneity and environmental factors play a critical role in the rate of disease progression and patients display faster declines once the symptoms have manifested. Since its original discovery, ALS has been associated with pathological alterations in motor neurons located in the spinal cord （SC）, where neuronal loss by a mutation in the protein superoxide dismutase in parenthesis （mSOD1） and impairment in axonal connectivity, have been linked to early functional impairments. In addition,mechanisms of neuroinflammation, apoptosis, necroptosis and autophagy have been also implicated in the development of this disease. Among different animal models developed to study ALS, the transgenic g93A-SOD1 mouse has become recognized as a benchmark model for preclinical screening of ALS therapies. Furthermore, the progressive alterations in the locomotor phenotype expressed in this model closely resemble the progressive lower limb dysfunction of ALS patients. Among other imaging tools, MR diffusion tensor imaging （DTI） has emerged as a crucial, noninvasive and real time neuroimaging tool to gather information in ALS. One of the current concerns with the use of DTI is the lack of biological validation of the microstructural information given by this technique. Although clinical studies using DTI can provide a remarkable insight on the targets of neurodegeneration and disease course,they lack histological correlations. To address these shortcomings, preclinical models can be designed to validate the microstructural information unveiled by this particular MRI technique. Thus, the scope of this review is to describe how MRI diffusion and optical microscopy

关键词： ALS Diffusion tensor imaging as a tool to detect presymptomatic axonal degeneration in a preclinical spinal cord model of amyotrophic lateral sclerosis

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Multi-tissue transcriptomics of a unique monozygotic discordant twin case of severe progressive osseous heteroplasia

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genes & Diseases 2024年第3期11卷 22-25页

作者： Alberto gomez-Carballa Maria Jose Curras-Tuala Sara Pischedda Miriam Cebey-Lopez Jose gomez-Rial Irene Rivero-Cale Jacobo Pardo-seco Xabier Bello Sandra Viz-Lasheras Antonio Justicia-grande Julian Montoto-Louzao Alba Camino-Mera Isabel Ferreiros-Vidal Maximo Fraga Jose RAntunez rodolfo gomez Federico Martinon-Torres Antonio Salas genetics Vaccines and Infections Research Group(GENVIP)Instituto de Investigacion Sanitaria de SantiagoSantiagode CompostelaGalicia 15706Spain Translational Pediatrics and Infectious Diseases Department of PediatricsHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain Laboratorio de Inmunologia Servicio de Andlisis ClinicosHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain Unidade de Xenetica Instituto de Ciencias Forenses(INCIFOR)Facultade de MedicinaUniversidade de Santiago de Compostelaand GenPoB Research GroupInstituto de Investigacion SanitariaHospital Clinico Universitario de Santiago de CompostelaServicio Galego de Saude(SERGAS)Galicia 15706Spain Musculoskeletal Pathology group Instituto de Investigacion Sanitaria de SantiagoServicio Galego de Saude(SERGAS)Santiago de CompostelaGalicia 15706Spain Department of Pathology Hospital Clinico Universitario de Santiago de Compostela(SERGAS)Galicia 15706Spain Unidad Integrada de BiobancosBiomodelos 3D y Modelos Animales IDIS(lnstituto de Investigacion Sanitaria de Santiagode Compostela)Galicia15706Spain Centro de Investigacion Biomedica en Red de Enfermedades Respiratorias(CIBER-ES) MadridSpain

Progressive osseous heteroplasia(POH)is an ultra-rare autosomal dominant disabling disorder characterized by heterotopic ossification(HO).It is caused by heterozygous inactivating mutations in the gNAS(guanine nucleotide-binding protein alpha-stimulating activity polypeptide)***,the molecular mechanisms underlying HO remain poorly *** a treatment for POH is not yet available,the identification of the mechanisms driving POH in affected tissues using gene expression may be of great help to underestand the molecular basis of POH and develop new therapeutic approaches.

关键词： stimulating driving asi

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Nonlinear criterion for strength mobilization in brittle failure of rock and its extension to the tunnel scale

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International Journal of Mining Science and Technology 2022年第4期32卷 685-705页

作者： rodolfo Cabezas Javier Vallejos Faculty of Engineering and Technology Universidad San SebastianSantiagoChile Advanced Mining Technology Center Universidad de ChileSantiagoChile Department of Mining Engineering Universidad de ChileSantiagoChile

As underground excavations are getting deeper and field stresses increase, the behavior of intact rock blocks plays an increasingly important role in understanding and estimating the overall rock mass strength. To model the brittle behavior of intact rock blocks, the stress–strain curve is usually idealized considering a linear strength mobilization approach(cohesion-weakening-friction-strengthening, CWFS),however, it is well recognized that rock presents a nonlinear behavior in terms of the confining *** study extends the strength mobilization in brittle failure of rock using nonlinear criteria. To determine the model parameters, a standard statistical method that uses the complete laboratory stress–strain curves of the intact rock is employed. Several hypotheses of linear and nonlinear models are statistically compared for different types of rock and confining stress levels. Results demonstrate that the best approach to model the brittle failure of rock is to consider a nonlinear strength envelope, such as the Hoek-Brown criterion assuming a residual uniaxial compressive strength different from zero and a mi parameter that increases, both with simultaneous mobilization. This model helps to recreate highconfining conditions and a more realistic transition between peak and post-peak strength. The obtained parameters are discussed and compared with literature values to verify the validity and to develop guidelines for the estimation of parameters, providing an objective mobilization criterion. Finally, the nonlinear model was applied to a finite element code and extended to a tunnel scale in the brittle rock under high-stress conditions. A reasonable fit between the simulations and the in-situ overbreak measurements was found.

关键词： Nonlinear strength Strength mobilization Brittle failure Intact rock Scaling

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Antecedent Precipitation Index to Estimate Soil Moisture and Correlate as a Triggering Process in the Occurrence of Landslides

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International Journal of geosciences 2024年第1期15卷 70-86页

作者： Marcio Augusto Ernesto De Moraes Walter Manoel Mendes Filho rodolfo Moreda Mendes Cassiano Antonio Bortolozo Daniel Metodiev Marcio Roberto Magalhães De Andrade Harideva Marturano Egas Tatiana Sussel gonçalves Mendes Luana Albertani Pampuch CEMADEN - National Centre for Monitoring and Early Warnings of Natural Disasters General Coordination of Research and Development S&#227o José dos Campos Brazil Faculty of Science and Technology Goias Federal University Aparecida de Goi&#226nia Brazil Institute of Science and Technology S&#227o Paulo State University (Unesp) S&#227o José dos Campos Brazil

Landslides are highly dangerous phenomena that occur in different parts of the world and pose significant threats to human populations. Intense rainfall events are the main triggering process for landslides in urbanized slope regions, especially those considered high-risk areas. Various other factors contribute to the process;thus, it is essential to analyze the causes of such incidents in all possible ways. Soil moisture plays a critical role in the Earth’s surface-atmosphere interaction systems;hence, measurements and their estimations are crucial for understanding all processes involved in the water balance, especially those related to landslides. Soil moisture can be estimated from in-situ measurements using different sensors and techniques, satellite remote sensing, hydrological modeling, and indicators to index moisture conditions. Antecedent soil moisture can significantly impact runoff for the same rainfall event in a watershed. The Antecedent Precipitation Index (API) or “retained rainfall,” along with the antecedent moisture condition from the Natural Resources Conservation Service, is generally applied to estimate runoff in watersheds where data is limited or unavailable. This work aims to explore API in estimating soil moisture and establish thresholds based on landslide occurrences. The estimated soil moisture will be compared and calibrated using measurements obtained through multisensor capacitance probes installed in a high-risk area located in the mountainous region of Campos do Jordão municipality, São Paulo, Brazil. The API used in the calculation has been modified, where the recession coefficient depends on air temperature variability as well as the climatological mean temperature, which can be considered as losses in the water balance due to evapotranspiration. Once the API is calibrated, it will be used to extrapolate to the entire watershed and consequently estimate soil moisture. By utilizing recorded mass movements and comparing them with AP

关键词： Landslides Antecedent Precipitation Index Soil Moisture Threshold Water Balance

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Fortification Challenges and Needs

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Biomedical and Environmental Sciences 2001年第1期14卷 98-103页

作者： rodolfo F. FLORENTINO President Philippine Association of Nutrition Philippines

Experience in many parts of the developing world has shown that food fortification offers a cost_effective and sustainable solution to the problem of micronutrient malnutrition. Building on the advances in science and technology and backed by studies on the economic benefits of fortification programs, governments and industry are beginning to respond positively to the call of nutrition advocates to adopt fortification as a long_term strategy. On the other hand, formidable challenges still remain in many countries in Asia, constraining the widespread adoption of this strategy. The science and technology community needs to provide adequate scientific and technological information as basis for planning and decision making. The government faces the challenge of providing the enabling environment for all stakeholders to cooperate in the fortification effort. Industry faces the challenge of adapting its production system to the requirements of fortification in order that they can contribute to social objectives while pursuing their economic objectives. The international and bilateral aid agencies need to seek tried and innovative ways to support the multiple players of food fortification, as these players in turn face the challenges that confront them.

关键词： science and technology production system economic benefits decision making in order

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Convergence in L^p-norm of Fourier Series on the Complete Product of Quaternion groups with Bounded Orders

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Acta Mathematica Sinica,English Series 2014年第9期30卷 1566-1578页

作者： gyrgy gAT rodolfo TOLEDO College of Nyiregyhza Inst.of Math.and Comp.Sci.Nyiregyhza

A well-known result for Vilenkin systems is the fact that for all 1 〈 p 〈 oc the n-th partial sums of Fourier series of all functions in the space Lp converge to the function in LP-norm. This statement can not be generalized to any representative product system on the complete product of finite non-abelian groups, but even then it is true for the complete product of quaternion groups with bounded orders and monomial representative product system ordered in a specific way.

关键词： Fourier analysis Walsh-Paley system representative product systems complete product of quaternion groups convergence in norm

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