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Geomorphic indices and relative tectonic uplift in the Guerrero sector of the Mexican forearc

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Geoscience Frontiers 2017年第4期8卷 885-902页

作者： Krzysztof Gaidzik María Teresa ramírez-Herrera Laboratorio Universitario de Geofísica Ambiental & Instituto de Geografía Universidad Nacional Autónoma de MéxicoCiudad Universitaria Berkeley Seismological Laboratory Department of Earth and Planetary ScienceUniversity of California Berkeley

Tectonically active areas,such as forearc regions,commonly show contrasting relief,differential tectonic uplift,variations in erosion rates,in river incision,and in channel gradient produced by ongoing tectonic ***,information on the tectonic activity of a defined area could be derived via landscape *** study uses topography and geomorphic indices to extract signals of ongoing tectonic deformation along the Mexican subduction forearc within the Guerrero *** this purpose,we use field data,topographical data,knickpoints,the ratio of volume to area（Rva）.the stream-length gradient index（St）,and the normalized channel steepness index（k_（sn））.The results of the applied landscape analysis reveal considerable variations in relief,topography and geomorphic indices values along the Guerrero sector of the Mexican subduction *** argue that the reported differences are indicative of tectonic deformation and of variations in relative tectonic uplift along the studied forearc.A significant drop from central and eastern parts of the study area towards the west in values of R_（VA）（from ~500 to^300）,St（from ~500 to ca.400）,maximum St（from ~1500-2500 to ~ 1000） and k_（sn）（from ~150 to ~100） denotes a decrease in relative tectonic uplift in the same *** suggest that applied geomorphic indices values and forearc topography are independent of climate and *** mechanisms responsible for the observed variations and inferred changes in relative forearc tectonic uplift call for further studies that explain the physical processes that control the forearc along strike uplift variations and that determine the rates of *** proposed methodology and results obtained through this study could prove useful to scientists who study the geomorphology of forearc regions and active subduction zones.

关键词： Relative tectonic uplift Forearc Active tectonics Geomorphic index Drainage network Mexican subduction zone

Displacement Field due to Nonuniform Slip along a Long Dip-Slip Fault in Two Welded Half-Spaces

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Journal of Earth Science 2012年第6期23卷 864-872页

作者： Sunita Rani Neeru Bala ram Chander Verma Department of Mathematics Guru Jambheshwar University of Science and TechnologyHisar 125001India

The solution of static deformation of two homogeneous, isotropic, and perfectly elastic half-spaces in welded contact due to a long dip-slip fault with uniform slip is well known. The aim of the present article is to obtain the static deformation of two homogeneous, isotropic, and perfectly elastic half-spaces in welded contact due to nonuniform slip along a long dip-slip fault. The fault is vertical and lies entirely in the lower half-space, extending up to the interface. Four slip profiles are considered： lin- ear, parabolic, elliptic, and cubic. Closed-form expressions for the elastic residual field have been ob- tained for the different slip profiles. The displacement field due to four nonuniform slip profiles is com- pared with the displacement field due to uniform slip. For comparison, we have assumed the source potency for different slip profiles to be the same, which is achieved by taking the fault slip at the inter- face constant and varying the fault width. It is found that the displacement field varies significantly at the fault width rather than at the interface. Moreover, uniform slip along the fault makes the edges singular. This singularity at the lower edge is not present in the case of nonuniform slip along a long dip-slip fault.

关键词： nonuniform slip two welded half-spaces dip-slip fault displacement field.

Comparative study of travelling-wave and numerical solutions for the coupled short pulse (CSP) equation

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Chinese Physics B 2013年第5期22卷 60-66页

作者： Vikas Kumar R. K. Gupta ram Jiwari School of Mathematics and Computer Applications Thapar University

The Lie symmetry analysis is performed for the coupled short plus （CSP） equation. We derive the infinitesimals that admit the classical symmetry group. Five types arise depending on the nature of the Lie symmetry generator. In all types, we find reductions in terms of system of ordinary differential equations, and exact solutions of the CSP equation are derived, which are compared with numerical solutions using the classical fourth-order Runge-Kutta scheme.

关键词： coupled short pulse (CSP) equation Lie symmetric analysis Runge-Kutta scheme exact solutions

Effect of sintering temperature on phase evolution of Al86Ni6Y4.5Co2La1.5 bulk amorphous composites synthesized via mechanical alloying and spark plasma sintering

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Progress in Natural Science:Materials International 2019年第1期29卷 32-40页

作者： Ashutosh Sahu ram Sajeevan Maurya Tapas Laha Department of Metallurgical and Materials Engineering Indian Institute of Technology Department of Metallurgical and Materials Engineering National Institute of Technology

Al86Ni6Y4.5Co2La1.5amorphous powders were synthesized by mechanical alloying for 200 h. Subsequent consolidation was performed via spark plasma sintering in the temperature range of 250 ℃ to 500 ℃ at the pressure of 500 MPa. The role of viscous flow on densification was investigated by studying the viscosity change of the amorphous phase at different consolidation temperatures. The decrease in viscosity at higher sintering temperatures resulted in better particle bonding and densification of consolidated samples. The formation of only FCC Al was observed in the consolidated samples at sintering temperatures ≤ 300 ℃ and the intermetallic phases formed at temperatures ≥ 400 ℃. The mechanical properties of the bulk samples were measured by Vickers microhardness and nanoindentation tests. The testing results showed that the average values of microhardness, nanohardness and elastic modulus of the sample consolidated at 500 ℃ were 3.06 ± 0.14 GPa,4.85 ± 1.14 GPa and 89.53 ± 9.25 GPa, respectively. The increase in hardness and elastic modulus of the higher temperature consolidated samples is attributed to the improvement in particle bonding, densification and distribution of various hard intermetallic phases in the amorphous matrix.

关键词： Al based glassy alloy Mechanical alloying Spark plasma sintering Intermetallic phase Viscosity

Long-term patterns in Iberian hare population dynamics in a protected area(Doñana National Park)in the southwestern Iberian Peninsula:Effects of weather conditions and plant cover

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Integrative Zoology 2017年第1期12卷 49-60页

作者： Francisco CARRO ramón C.SORIGUER Doñana Biological Station(CSIC) the Monitoring Team on Natural Resources and Processes of the Doñana Biological Station Ethology and Biodiversity Conservation SevillaSpain

The Iberian hare(Lepus granatensis)is a widely distributed endemic species in the Iberian *** improve our knowledge of its population dynamics,the relative abundance and population trends of the Iberian hare were studied in the autumns of 1995-2012 in a protected area(Doñana National Park)by spotlighting in 2 different habitats:marshland and *** average relative abundance was 0.38 hare/km(SD=0.63)in the marshland and 3.6 hares/km(SD=4.09)in *** Iberian hare population exhibited local interannual fluctuations and a negative population trend during the study period(1995-2012).The results suggest that its populations are in *** flooding of parts of the marshland in June,July and October favor hare abundance in the *** abundance in the marshland increases as the flooded surface area increases in *** effects are more pronounced if the rains are early(October)and partially flood the *** contrast,when marsh grasses and graminoids are very high and thick(as measured using the aerial herbaceous biomass[biomass marshland]as a proxy),the abundance of hares decreases dramatically as does the area of the marsh that is flooded(in November).

关键词： Doñana Iberian Peninsula Lepus granatensis population dynamics trends

Resveratrol as an inductor of autophagy: is there a unique pathway of activation?

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Neural Regeneration Research 2021年第1期16卷 101-103页

作者： Narayana Pineda-ramírez Penélope Aguilera Laboratorio de Patología Vascular Cerebral.Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez Ciudad de MéxicoMéxico

Autophagy is a process of cellular degradation for the removal of damaged components and eventual recycling of the resulting molecules that help to the maintenance of cellular *** this pathway,proteins with relatively long half-life and whole organelles(e.g.,mitochondria,peroxisomes,and ribosomes)are degraded in the cytoplasm for the continuous turnover of cellular structures to facilitate their ***,the beneficial effect of autophagy goes beyond cellular“cleaning”and resides to a large extent on its ability to recycle cell components back into the ***,autophagy is a fundamental mechanism to regulate cellular functions,including DNA repair,proliferation,differentiation,embryonic development,and the immune response.

关键词： homeostasis activation autophagy

Dietary(poly)phenol intake is associated with cardiometabolic health parameters in adolescents

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Food Science and Human Wellness 2024年

作者： Emily P.Laveriano-Santos Sara Castro-Barquero Camila Arancibia-Riveros Ana María Ruiz-León Rosa Casas ramón Estruch Patricia Bodega Mercedes de Miguel Amaya de Cos-Gandoy Jesús Martínez-Gómez Gloria Santos-Beneit Juan M.Fernández-Alvira Rodrigo Fernández-Jiménez Rosa M.Lamuela-Raventós Anna Tresserra-Rimbau The Zena and Michael A.Wiener Cardiovascular Institute， Icahn School of Medicine at Mount Sinai Department de Nutrició， Ciències de l'Alimentació I Gastronomia， XIA， Facultat de Farmàcia i Ciències de l'alimentació， Institut de Recerca en Nutrició i Seguretat Alimentària (INSA-UB)， Universitat de Barcelona Department of Internal Medicine， Hospital Clínic， Institutd'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS)， University of Barcelona Consorcio CIBER， M.P.Fisiopatología de la Obesidad y Nutrición (CIBERObn)， Instituto de Salud Carlos III (ISCIII) Mediterranean Diet Foundation 5. Foundation for Science， Health and Education (SHE) 6. Centro Nacional de Investigaciones Cardiovasculares (CNIC) CIBER de Enfermedades Cardiovasculares (CIBERCV) 9. Hospital Universitario Clínico San Carlos

Background: The protective role of (poly)phenols against metabolic disorders has been extensively studied in adults but not in ***: To assess associations of dietary (poly)phenols and their subclasses with cardiometabolic health parameters in adolescents. Methods: A cross-sectional study was conducted in 944 individuals aged 11 to 14 years enrolled in the SI! Program for Secondary Schools trial (NCT03504059). (Poly)phenol intake was assessed using semi-quantitative food frequency questionnaires and the Phenol-Explorer database. The measured cardiometabolic parameters were waist circumference (WC) age-sex z-score， blood pressure (BP) age-sex z-score， blood glucose (BG)， triglycerides (TG)， and high-density lipoprotein cholesterol (HDL-c). Multilevel mixed-effect linear regression models were applied to examine the association between (poly)phenol quintiles and cardiometabolic health ***: Compared to the lowest quintile， adolescents in the highest quintile of total (poly)phenol intake had lower WC z-scores (β=-0.09， 95%CI=-0.09;-0.08， P-for trend=0.002)， mean arterial pressure z-scores (β =-0.11， 95%CI=-0.12;-0.09， P-for trend=0.206)， and HDL-c (β=-1.52， 95%CI=-2.90;-0.14， P-for trend=0.108)， after multivariable adjustment. The WC z-scores (β=-0.11， 95%CI=-0.19;-0.03， P-for trend=0.013) and HDL-c (β=-2.16， 95%CI=-3.78;-0.53， P-for trend=0.046) were lower in the highest quintile of flavonoid intake compared to the lowest quintile. The highest quintile of phenolic acid intake was associated with a lower WC z-score (β=-0.14， 95%CI=-0.26;-0.02， P-for trend=0.011) and TG levels (β=-8.83， 95%CI=-12.37;-5.30， P-for trend <0.001)， and the highest quintile of stilbene intake with lower BG (β=-1.83， 95%CI= -3.103;-0.64， P-for trend <0.001) and TG (β=-3.22， 95%CI= -4.95;-1.49， P-for trend=0.034)， and with higher HDL-c (β=2.328， 95%CI= 1.40;3.17， P-for trend=0.466) compared to the lowest quintile. Conclusion: A higher intake of (poly)phenols， espe

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Real-World Evidence in Localized Pancreatic: Coping with Uncertainty in Unselected Populations

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Journal of Cancer Therapy 2024年第4期15卷 164-178页

作者： María I. Pamies ramón Diana Ibarra Anguita Paula Rodríguez Payá Alvaro Muñoz Abad David Sánchez García María Valero Revert Beatriz Grau Mirete Mariano Martínez Marín Alicia Calero Amaro Lorena Rodríguez Cazalla Javier Gallego Plazas Medical Oncology Department Elche University Hospital Elche (Alicante) Spain General Surgery Department Elche University Hospital Elche (Alicante) Spain General Surgery Department Vega Baja Hospital Orihuela (Alicante) Spain

Background: Localized pancreatic cancer, including resectable (R), borderline resectable (BR) and locally advanced unresectable disease (LAU), is considered in clinical guidelines for diverse treatment options based on clinical trials in selected populations. Hence, exploring with real world evidence (RWE) clinicians’ preferences for treatment options and their results seems pertinent. Methods: In a set of consecutive patients with localized pancreatic cancer assisted in a third level hospital from January 2013 to December 2022, medical records, symptoms, diagnostic process, distribution between subtypes, and treatment plans, with safety and efficacy results, were assessed. Results: A total of 152 patients with localized disease were included (43.4% R, 21.0% BR, 33.6% LAU). The population characteristics exemplified differences between daily practice and clinical trials. Tumor location and symptoms were as expected. Treatment plan was conditioned by PS or comorbidities in 23.0% of patients. In patients with R disease, surgery followed by different adjuvant chemotherapy (CT) regimes was the antineoplastic treatment of choice (64.8%) with efficacy results (OS 37.5 months;95% CI 18.4 - 56.7), in the range of contemporary standards. The common use of neoadjuvant CT for BR disease (94.4%), with surgery in 50% of them, and its results (OS 30.8 months;95% CI 10.5 - 51.2) reflected current controversies of treatment recommendations and evolution in this scenario. Paliative CT with or without radiotherapy was the standard specific treatment in LAU disease (95.1%) with survival results (PFS: 10.8 months;95% CI 8.8 - 12.7. OS: 20.3 months;95% CI 13.5 - 27.2) that justify the distinct character and the specific study of this entity. Conclusion: RWE for localized pancreatic cancer aroused from the analysis of this population confirms the distinct nature of patients assisted in daily practice, as well as mirrors the complexity of decision making in clinical assumptions in which a

关键词： Real-World Evidence Localized Pancreatic Cancer

An efficient algorithm to clip a 2D-polygon against a rectangular clip window

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Applied Mathematics(A Journal of Chinese Universities) 2022年第1期37卷 147-158页

作者： Sushil Chandra Dimri Umesh Kumar Tiwari Mangey ram Department of Computer Science and Engineering Graphic Era(Deemed to be University)DehradunUttarakhandIndia

Polygon clipping is of great importance in computer *** of the popular algorithms to clip a polygon is Cohan–Sutherland Hodgeman algorithm which is based on line ***–Sutherland Hodgeman algorithm clips the polygon against the given rectangular clip window with the help of line clipping ***–Sutherland algorithm requires traversing the polygon in anti clockwise direction(positive orientation).In this work we propose an efficient polygon clipping algorithm against a rectangular clip *** algorithm uses parametric representation of polygon *** the concept of point clipping,we can find required intersection points of edges of polygon with clip window *** suited numerical illustrations are used to explain the proposed polygon clipping *** proposed algorithm is computationally less expensive and comprehensive.

关键词： point clipping polygon clipping clip window line segment computational complexity