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On a Classical Theorem on the Diameter and Minimum Degree of a Graph

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Acta Mathematica Sinica,English Series 2017年第11期33卷 1477-1503页

作者： Veronica HERNANDEZ Domingo PESTANA jose M. RODRIGUEZ Universidad carlosⅢde Madrid Avenida de la Universidad3028911 LeganesSpain

In this work, we obtain good upper bounds for the diameter of any graph in terms of its minimum degree and its order, improving a classical theorem due to Erdos, Pach, Pollack and Tuza. We use these bounds in order to study hyperbolic graphs （in the Gromov sense）. To compute the hyperbolicity constant is an almost intractable problem, thus it is natural to try to bound it in terms of some parameters of the graph. Let H（n, δ0） be the set of graphs G with n vertices and minimum degree 50, and J（n, Δ） be the set of graphs G with n vertices and maximum degree A. We study the four following extremal problems on graphs： a（n,δ0） = min{δ（G）｜ G ∈H（n, δ0）}, b（n, δ0） =- max{δ（G）｜ e ∈H（n, δ0）}, α（n, Δ） = min{δ（G） [ G ∈ J（n, Δ）} and β（n,Δ） = max{δ（G） ] G∈Π（n,Δ）}. In particular, we obtain bounds for b（n, δ0） and we compute the precise value of a（n, δ0）, α（n, Δ） and w（n, Δ） for all values of n, r0 and A, respectively.

关键词： Extremal problems on graphs diameter minimum degree maximum degree Gromov hyperbolicity hyperbolicity constant finite graphs

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Nonlinear constrained optimization using the flexible tolerance method hybridized with different unconstrained methods

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Chinese Journal of Chemical Engineering 2017年第4期25卷 442-452页

作者： Alice Medeiros Lima Antonio jose Goncalves Cruz Wu Hong Kwong Chemical Engineering Graduate Program Federal University of Sdo CarlosRodovia Washington Luizkm 235-5P310Sao CarlosSP 13565-905Brazil Department of Chemical Engineering Federal University of Sao CarlosRodovia Washington Luizkm 235-SP 310Silo CarlosSP 13565-905Brazil

This paper proposes the use of the flexible tolerance method(FTM) modified with scaling of variables and hybridized with different unconstrained optimization methods to solve real constrained optimization *** benchmark problems used to analyze the performance of the methods were taken from G-Suite *** original method(FTM) and other four proposed methods:(i) FTM with scaling of variables(FTMS),(ii) FTMS hybridized with BFGS(FTMS-BFGS),(iii) FTMS hybridized with modified Powell's method(FTMS-Powell)and(iv) FTMS hybridized with PSO(FTMS-PSO), were implemented. The success rates of the methods were 80%,100%, 75%, 95% and 85%, for FTM, FTMS, FTMS-BFGS, FTMS-Powell and FTMS-PSO, respectively. Numerical experiments including real constrained problems indicated that FTMS gave the best performance, followed by FTMSPowell and FTMS-PSO. Despite the inferior performance compared to FTMS and FTMS-Powell, the FTMS-PSO method presented some advantages since good different initial points could be obtained, which allow exploring different routes through the solution space and to escape from local optima. The proposed methods proved to be an effective way of improving the performance of the original FTM.

关键词： Flexible tolerance method Modified Powell’s method BFGS PSO Scaling Hybridization

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Inner ear hair cell regeneration A look from the past to the future

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Neural Regeneration Research 2013年第24期8卷 2284-2289页

作者： Francisco Santaolalla carlos Salvador Agustín Martínez jose María Sánchez Ana Sánchez del Rey Department of Otorhinolaryngology Basurto University Hospital Department of Dermatology Ophthalmology and Otorhinolaryngology School of Medicine University of the Basque Country (UPV/EHU)

Most recent studies on regeneration of inner ear hair cells focus on use of stem cells, gene therapy and neurotrophic factors. Cochlear gene therapy has been successfully used in the treatment of neu- rosensory hearing loss. This suggests that cochlear hair cell regeneration is possible. The objective of this paper is to review research and clinical application of inner near hair cell regeneration.

关键词： neural regeneration reviews hearing loss hair cells cochlea genes stem cells viral vectors regeneration neuroregeneration

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Giant and thrombosed left ventricular aneurysm

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World Journal of Cardiology 2015年第7期7卷 431-433页

作者： jose Alberto de Agustin jose Juan Gomez de Diego Pedro Marcos-Alberca jose Luis Rodrigo carlos Almeria Patricia Mahia Maria Luaces Miguel Angel Garcia-Fernandez carlos Macaya Leopoldo Perez de Isla Instituto Cardiovascular Hospital Universitario San Carlos

Left ventricular aneurysms are a frequent complication of acute extensive myocardial infarction and are most commonly located at the ventricular apex. A timely diagnosis is vital due to the serious complications that can occur,including heart failure,thromboembolism,or tachyarrhythmias. We report the case of a 78-yearold male with history of previous anterior myocardial infarction and currently under evaluation by chronic heart failure. Transthoracic echocardiogram revealed a huge thrombosed and calcified anteroapical left ventricular aneurysm. Coronary angiography demonstrated that the left anterior descending artery was chronically occluded,and revealed a big and spherical mass with calcified borders in the left hemithorax. Left ventriculogram confirmed that this spherical mass was a giant calcified left ventricular aneurysm,causing very severe left ventricular systolic dysfunction. The patient underwent cardioverter-defibrillator implantation for primary prevention.

关键词： Myocardial infarction Echocardiography Coronary artery disease Left ventricular aneurysm Coronary angiography

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小功率电隔离DC/DC变换器

电子设计技术 1999年第2期 48-48,50页

作者： jose carrasco Universidad De Valencia Spain

有些小功率设备需要简单、廉价,但是输出直流电压和输入直流电压隔离的电源。图1是能够满足这种要求的DC/DC变换器,它由几只器件及一只小型变压器组成,能够输出12V、150mW。输入可取自14V～18V的任何电源。反相器CD40106/4049和反馈电... 详细信息

有些小功率设备需要简单、廉价,但是输出直流电压和输入直流电压隔离的电源。图1是能够满足这种要求的DC/DC变换器,它由几只器件及一只小型变压器组成,能够输出12V、150mW。输入可取自14V～18V的任何电源。反相器CD40106/4049和反馈电阻器构成一个振荡器,工作频率约为200kHz(图2)。振荡器波形的不对称性取决于反馈电阻器的数值。

关键词：变换器转换器 DC/DC 小功率

Determination and Analysis of Hot Spot Areas of Deforestation Using Remote Sensing and Geographic Information System Techniques. Case Study: State Sinaloa, México

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Open Journal of Forestry 2016年第4期6卷 295-304页

作者： Sergio Alberto Monjardin Armenta carlos Eduardo Pacheco Angulo Wenseslao Plata Rocha Gabriela Corrales Barraza Rosendo Romero Andrade jose carlos Beltran Gonzalez Faculty of Earth Sciences and Space The Autonomous University of Sinaloa Culiacan México Faculty of Forestry and Environmental Sciences University of the Andes Merida Venezuela

The main objective of this research is to analyze deforestation in State Sinaloa during the period 1990-2014. For this, “deforestationhot-spot areas” were identified, by crossing maps of 1993 and 2011 at a 1:250,000 scale with knowledge from environmental and forest experts from each region. Landsat images from 1990 and 2014 and Terra Amazon System were used to monitor the most critical hot spot area, applying Linear Spectral Mixture Analysis and Image Segmentation Ground Product. In order to generate the map deforestation year zero (1990), every segmented object of ground product was visually assigned to “Forest” and “No-Forest” categories. Therefore, gains and losses were interpreted for the map deforestation year one (2014). Those products were validated with the help of experts on the subject and applying a confusion matrix. Results obtained indicated that the highest forest loss was located in North-Central Sinaloa (hot spot area number two) by establishing the average annual rate of deforestation of 4741.90 ha/year with an average rate of 0.60%, being higher than the national average rate (0.37%). This result affects directlyon calculation of carbonfluxes at nationallevel.

关键词： Deforestation Hot Spot GIS Landsat Terra Amazon

Serial Ultrasonographic Measurements to Estimate Age and Viability in <i>Bos indicus</i>Embryos

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Open Journal of Veterinary Medicine 2019年第7期9卷 91-99页

作者： Ana Lucia Malvaez carlos Salvador Galina Ivette Gutierrez Manuel Corro jose Luis Pablos Departamento de Reproducción Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Centro de Enseñ anza Investigación y Extensión en Ganadería Tropical Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autónoma de México Tlapacoyan Veracruz México Departamento de Genética y Bioestadística Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México

Early pregnancy diagnosis is a very important routine management to identify non-pregnant cows in order to keep an optimum reproductive efficiency both for dairy and beef cows. Ultrasound equipment allows estimating the viability and size of the embryo during early gestation. With the aim of assessing age and viability of Bos indicus embryos between 24 and 35 days of gestation, 55 cows were divided into 4 clusters. These clusters were conformed according to the first day that an echogenic structure was seen inside the embryonic vesicle (Group 1: day 24, Group 2: day 26, Group 3: day 27 and Group 4: day 28). The age of the embryos was estimated from the date of AI. Three progressive serial measurements of their length were made within 2 to 5 days. With a model GEE (Generalized Estimating Equations), the effect of days was evaluated to compare the second measurement with the first one and the former with the third observation. No differences in the size of the embryos were observed between the first evaluation (24 days) and the second (28 days) (P = 0.387). Also, simple linear regression analysis found a positive linear association between the size of the embryo and gestation days (R2 = 0.593) with an average growth of 0.078 cm per day (P = 0.001). In conclusion, the variation between measurements at a given time does not allow estimating with precision the exact day of gestation. Nonetheless, serial measurements are useful to estimate the healthy growth of the embryo from day 26 of gestation.

关键词： Zebu Cattle Embryo Measurement Reproduction Tropics

Preparation of High Purity Neodymium Oxide from Brazilian Monazite by Ion Exchange

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Journal of Energy and Power Engineering 2015年第7期9卷 616-621页

作者： carlos Alberto da Silva Queiroz jose Antonio Seneda Walter dos Reis Pedreira Filho IPEN/CNEN-SP (Instituto de Pesquisas Energeticas e Nucleares/Comissao Nacional de Eneergia Nuclear-Sao Paulo) Cidade Universitaria Sao Paulo 05508-000. Brazil Fundacao Jorge Duprat Figueiredo de Seguranca e Medicina do Trabalho-FUNDACENTRO Sao Paulo 05409-002 Brazil

A simple and economical chemical process for obtaining high purity neodymium oxide is discussed. The raw material in the form of RE （rare earth） carbonates is produced industrially in Brazil from monazite. Using this concentrate as the feed material, ion exchange with a strong cationic resin, commonly used for water treatment, and without the use of retention ions was used for the fractionating of the REE （rare earth elements）. The eluent was ammonium salt of EDTA （ethylenediaminetetraacetic acid） at pH 4.0. The complex of EDTA-neodymium was transformed into neodymium oxides via oxalate precipitation. We produced 99.9% pure Nd203 in yields greater than or equal to 80%. Molecular absorption spectrophotometry was used to monitor the neodymium content during the process and sector field inductively coupled plasma mass spectrometry was used to certify the purity of the neodymium oxides. The typical neodymium oxides obtained contained the followings contaminants in micrograms per gram： Sc （4.09）; Y （0.39）; La （0.78）; Ce （5.62）; Pr （4.56）; Sm （11.10）; Eu （1.10）; Gd （14.30）; Tb （29.3）; Dy （4.15）; Ho （8.39）; Er （13.80）; Tm （0.23）; Yb （2.29）; Lu （0.39）. High purity neodymium oxides obtained from this procedure replaced the imported product used in research and development work on rare earth at IPEN/CNEN-SP （Instituto de Pesquisas Energeticas e Nucleares/Comissfio Nacional de Eneergia Nuclear-Sao Paulo）.

关键词： Neodymium oxide elemental rare earths separation rare earths.

Spanish National Monuments with Traditional Timber Roofs： Restoration versus Reconstruction

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Journal of Civil Engineering and Architecture 2011年第9期5卷 828-834页

作者： Javier Garabito jose carlos Garabito Victor Echarri Angel Rodriguez Jesus Gadea Veronica Calderon Department of Building Construction University of Burgos Spain Department of Civil Engineering University of Burgos Spain Department of Building Construction University of Alicante Spain

We prioritize interventions in the roof structure in order to prevent subsequent deterioration of the monument. This presentation refers to interventions in two Spanish National Monuments： the Collegiate Church of Roa de Duero and San Esteban＇s church of Los Balbases. The Collegiate Church was built during the 16th century. It is considered the jewel of the villa. It is a ＂hallenkirche＂ model with three big naves of the same height covered by beautiful starry vaults. The intervention consisted of restoring the wooden roof structure, preserving the original 16th centary structure, by replacing the damaged elements. It was restored according to archaeological criteria. San Esteban＇s church is a 13 century Gothic style church with a Latin cross plan. It has three naves with a transept of great slenderness. It preserves Romanesque remains. Opposite to the previous intervention we decided to rebuild the roof because the former roof was totally distorted due to bad executed works during the past Century. In this way we regain the original shape of the church. These interventions aim to improve constructive and structural conditions as well as retrieve the image of both monuments. We have studied the visual impact of interventions through virtual recreations. The intervention criteria are very different, restoration versus structttral reconstruction.

关键词： Restoration roof timber structure heritage laminated wood.