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The Nikola Tesla Constant and Its Relation to the Circumference Inscribed in a Square

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Journal of Applied Mathematics and Physics 2024年第1期12卷 277-283页

作者： Javier Mendoza Navarrete José Ismael Ojeda Campaña Huetzin Perez Gabriel Luna-Sandoval Victor Verdugo Ricardo Jiménez Garcia departamento de Matemáticas CBTis 256 DGETI Cabo San Lucas México División de Ingeniería en Sistemas Computacionales Tecnológico Nacional de México/ITES de Los Cabos Cabo San Lucas México DCI departamento de Física Médica Universidad de Guanajuato León México departamento de Ingeniería Industrial en Manufactura Universidad Estatal de Sonora Navojoa México departamento de Eléctrica-Electrónica Tecnológico Nacional de México Campus Mexicali Mexicali México

This research work relates the surface of a square and the area circumscribed by a circle, resulting in a value called Nikola Tesla constant. This constant starts with the calculation of the areas of the square and the inscribed circle, giving a ratio of 9/40 and from which a residual area of the area proportions of the geometric figures described is obtained. Plotting smooth curves, particularly those in round shapes, can be represented efficiently with the use of Nikola Tesla constant, reducing complex mathematical calculus.

关键词： Tesla Numbers Prime Number Circle Binary Area

Distribution and Relation of Primes with Tesla Numbers 3, 6, and 9

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Journal of Applied Mathematics and Physics 2024年第4期12卷 1021-1027页

作者： Javier Mendoza-Navarrete Huetzin Perez Ismael Ojeda Victor Verdugo Gabriel Luna Sandoval Ricardo Jimenez Garcia Jaime Alvarez departametno de Matemá ticas CBTis 256 DGETI Cabo San Lucas M&#233xico DCI departamento de Fisica Mé dica Universidad de Guanajuato Leon M&#233xico Divisió n de Ingenieria en Sistemas Computacionales Tecnol&#243gico Nacional de M&#233xico ITES Los Cabos Cabo San Lucas M&#233xico departamento de Ingenieria Industrial en Manufactura Universidad Estatal de Sonora Navojoa M&#233xico departamento de Elé ctrica-Electr&#243nica Tecnol&#243gico Nacional de M&#233xico Campus Mexicali Mexicali M&#233xico guanajuato M&#233xico

This work presents a different approach to twin primes, an approach from the perspective of the Tesla numbers and gives a refresh and new observation of twin primes that could lead us to an answer to the Twin Prime Conjecture problem. We expose a peculiar relation between twin primes and the generation of prime numbers with Tesla numbers. Tesla numbers seem to be present in so many domains like time, vibration and frequency [1], and the space between twin primes is not the exception. Let us say that twin primes are more than just prime numbers plus 2 or minus 2, and Tesla numbers are more involved with twin primes than we think, and hopefully, this approach give us a better understanding of the distribution of the twin pairs.

关键词： Tesla Numbers Prime Number Twin Prime Numbers Twin Pair

Ageism: Millennial Persistence

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Advances in Aging Research 2024年第1期13卷 1-14页

作者： Alejandro Klein Oxford Institute of Population Ageing University of Guanajuato Leon Mexico

This work develops the idea that is possible to affirm that beyond its nuances. Ageism has shown a surprising force of prevalence in western society. Nourished by mythical, empirical, ideological and health elements, it has been enormously successful in imposing an image of vulnerability, decrepitude and illness on older adults. Since 1969, when the first academic article on the subject was published, much has been written on the subject, but little progress has been made in terms of social and state policies and community awareness. When an attempt has been made to propose an alternative to decrepit (Aristotelian as we suggest in this paper) ageism, nothing has emerged but a new kind of ageism that has imposed the supposed need that the older adult “must” be “productive”, “young”, “vigorous”, posing the impossibility, in short, once again, of the older adult living spontaneously as an older adult.

关键词： Ageism Stereotypes Prejudices

Root Sprouts of Domesticated Phaseolus coccineus L. Overwinter Plants and the Environment at Its Collection Sites

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Open Journal of Ecology 2024年第5期14卷 508-521页

作者： Ma. Luisa Patricia Vargas-Vázquez Jorge Alberto Acosta-Gallegos Fabián Islas-Gutiérrez Enrique Buendía-Rodríguez Campo Experimental Valle de Mé xico Instituto Nacional de Investigaciones Forestales Agr&#237colas y Pecuarias Texcoco Mexico Campo Experimental Bají o Instituto Nacional de Investigaciones Forestales Agr&#237colas y Pecuarias Guanajuato M&#233xico

Buds emerge from the roots of domesticated runner bean plants (Phaseolus coccineus L.) as sprouts and give the crop its persistence. This particularity of the species seems to be associated with the environment where the species was cultivated during long time. Data on regrowth traits were recorded on 70 accessions of domesticated P. coccineus after overwintering at a site in the central highlands of Mexico. The characteristics recorded included fresh weight of vegetative regrowth, root length, root crown diameter, and diameter of the main root. Most accessions that sprout the following spring, after the grain harvest of the previous year, come from temperate and semi-cold sites with cambisol and andosol soils in mixed Quercus pine forest and high mountain fir trees. Those that do not sprout are from sites of semiarid temperate climate, haplic phaeozem soil in shrub grasslands with deciduous broadleaved trees, and semiwarm subhumid climate, eutrophic regosol soil in deciduous broadleaved forest. Two types of roots were differentiated: branched and thickened taproots, also associated with a different climate, and the type of soil of the collection sites.

关键词： P. coccineus Distribution Vegetation-Environment Interactions Drought-Alternative Species Root-Regrowth

In Vitro-Propagation of Agave tequilana Weber cv.azul in a Temporary Immersion System

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Phyton-International Journal of Experimental Botany 2022年第1期91卷 83-96页

作者： Otilio Vázquez-Martínez Héctor Gordon Núñez-Palenius Eugenio M.Pérez-Molphe Balch Mauricio Valencia-Posadas Luis Pérez-Moreno Graciela M.L.Ruiz-Aguilar M.Gómez-Lim División de Ciencias de la Vida Universidad de GuanajuatoIrapuato36500México departamento de Química Centro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientes20131México departamento de Ingeniería Genética CINVESTAV Unidad IrapuatoIrapuato36500México

In Mexico,there is a need to produce large quantities of plantlets for the establishment and replanting of blue(cv.azul)agave production areas.Most of these plots are within the origin denomination area(DOT,Spanish acronym)of the distilled product of this plant,known as tequila.The objective of this study was to develop an in vitropropagation protocol for Agave tequilana Weber cv.azul using segmented stems in both:solid and liquid media.A disinfection and in vitro technique were developed to obtain shoots,through plantlets collected in commercial plots,which attained 100%surface-disinfection and budding rate.At the multiplication stage,the effects of 6-Benzylaminopurine(BA)(0.0,4.4 and 13.2μM)and kinetin(0.0,9.4,18.8 and 37.6μM)were evaluated on lateralshoot production of segmented sagittal stems.These were cultivated on Murashige&Skoog(MS)medium,with the addition of 3.0%sucrose and 8 g L−1 agar.It was observed that BA and kinetin increased the number of shoots per explant,obtaining up to 18 and 26,respectively.Furthermore,it was found that just the sagittal segmentation of explants increased axillary budding.On the other hand,segmented-stem bases were grown in MS liquid medium with 3.0%sucrose,inside a RITAsystem,programmed by a 5 min immersion step with a frequency of every 4 h.The effect of Indole−3-Acetic acid(IAA)(0.57,2.9,5.7μM)was evaluated,while maintaining a concentration of BA(13.2μM).It was observed that the greatest concentration of IAA led to the formation of more than 20 buds per explant.These results offer a new methodology to increase the efficiency of A.tequilana Weber cv.azul-in vitro multiplication by sagittal segmentation of stems and the addition of BA and/or IAA.

关键词： Plant tissue culture stem-disk culture tequila in vitro culture

Strategic Analysis to develop an Internationalization Plan for a Small Construction Company in guanajuato,Mexico

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Chinese Business Review 2018年第5期17卷 209-222页

作者： María Guadalupe Arredondo-Hidalgo Diana del Consuelo Caldera-González Gerardo Alvarez-Valadez universidad de guanajuato GuanajuatoMéxico universidad Iberoamericana León GuanajuatoMéxico

Nowadays internationalization is no longer a luxury for companies and becomes a necessity in order to survive in the market and ensure its durability over time.This justifies the structure of a internationalization plan(IP)for a small company(SEC),in order to modify its value curve against the competition and guarantee a sustained growth development in new markets.This paper presents a strategic analysis of a small construction company dedicated to the elaboration of finishes for walls,floors,and concrete architecture.A situational analysis was carried out to see what would be the most appropriate international strategy for the company.Tools,such as:(a)SWOT(strengths,weaknesses,opportunities,threats)Analysis,(b)PEST(political,economic,social,and technological)Analysis,(c)Internal Factors Evaluation Matrix(IFE),and(d)External Factors Evaluation Matrix(EFE Assessment Matrix),were used to identify the current standing of the SEC.The canvas model and the competitive profile matrix were used to make the connection with the strategic position of the SEC against the desire of internationalization.Likewise,an analysis of the external factors was carried out showing a significant growth of 4.6%in the specialized sub-sector,as well as a tense business landscape driven by the political situation between Mexico and the United States.

关键词： small enterprise strategies internationalization

The protein-protein interaction landscape of transcription factors during gynoecium development in Arabidopsis

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Molecular Plant 2023年第1期16卷 260-278页

作者： Humberto Herrera-Ubaldo Sergio E.Campos Pablo López-Gómez Valentín Luna-García Víctor M.Zúñiga-Mayo Gerardo E.Armas-Caballero Karla L.González-Aguilera Alexander deLuna Nayelli Marsch-Martínez Carlos Espinosa-Soto Stefan de Folter Unidad de Genómica Avanzada(UGA-LANGEBIO) Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional(CINVESTAV-IPN)IrapuatoGuanajuato 36824México departamento de Biotecnología y Bioquímica Unidad IrapuatoCINVESTAV-IPNIrapuatoGuanajuato 36824México Instituto de Física Universidad de San Luis PotosíSan Luis PotosíSLP 78290México Present address:department of Plant Sciences University of CambridgeCambridgeUK Present address:department of Molecular and Cellular Biology University of California DavisDavisCAUSA Present address:CONACYT Instituto de FitosanidadColegio de PostgraduadosCampus MontecilloTexcocoMéxico

Flowers are composed of organs whose identity is defined by the combinatorial activity of transcription factors(TFs).The interactions between MADS-box TFs and protein complex formation have been schematized in the floral quartet model of flower development.The gynoecium is the flower’s female reproductive part,crucial for fruit and seed production and,hence,for reproductive success.After the establishment of carpel identity,many tissues arise to form a mature gynoecium.TFs have been described as regulators of gynoecium development,and some interactions and complexes have been identified.However,broad knowledge about the interactions among these TFs and their participation during development remains scarce.In this study,we used a systems biology approach to understand the formation of a complex reproductive unit—as the gynoecium—by mapping binary interactions between well-characterized TFs.We analyzed almost 4500 combinations and detected more than 250 protein-protein interactions(PPIs),resulting in a process-specific interaction map.Topological analyses suggest hidden functions and novel roles for many TFs.In addition,we observed a close relationship between TFs involved in auxin and cytokinin-signaling pathways and other TFs.Furthermore,we analyzed the network by combining PPI data,expression,and genetic data,which helped us to dissect it into several dynamic spatio-temporal subnetworks related to gynoecium development processes.Finally,we generated an extended PPI network that predicts new players in gynoecium development.Taken together,all these results serve as a valuable resource for the plant community.

关键词： interactome networks transcription factors gynoecium development

The RXTE/PCA 35-Day X-Ray Lightcurve of Hercules X-1

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International Journal of Astronomy and Astrophysics 2023年第3期13卷 172-194页

作者： denis Leahy Sandra Gonzalez Enriquez department of Physics and Astronomy University of Calgary Calgary Canada Division de Ciencias e Ingenierias Universidad de Guanajuato Guanajuato Mexico

The archival Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) observations of HZ Her/Her X-1 are analyzed here. The time periods for Anomalous Low States are refined. The 35-day X-ray lightcurve of Her X-1 is produced using 35-day phases determined with RXTE All-Sky Monitor (ASM) and Swift Burst Alert Telescope (BAT) data, with adjustments based on the RXTE/PCA data. As a result, we constructed the best-phased 35-day lightcurve of Her X-1 with the highest sensitivity. The RXTE/PCA data are separated into 8 different substates of the 35-day cycle: Main High (MH) turn-on, MH, MH decline, Low State (LS) 1, Short High (SH) turn-on, SH, SH decline, and LS2. Orbital lightcurves are created for each substate, and they are compared. Eclipse data are extracted for each substate to determine the changes in eclipse shape with 35-day phase. A scattering corona model is fit to the eclipses for the different 35-day substates: this shows that the corona is present with similar intensity at all 35-day phases. We search for previously reported dips without absorption but find none.

关键词： X-Ray Binaries Light-Curves Accretion Disks

A novel and stretchable carbon-nanotube/Ni@TiO_(2):W photocatalytic composite for the complete removal of diclofenac drug from the drinking water

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Journal of Environmental Sciences 2023年第4期126卷 575-589页

作者： Ernesto Valadez-Renteria Rafael Perez-Gonzalez Christian Gomez-Solis Luis Armando Diaz-Torres Armando Encinas Jorge Oliva Vicente Rodriguez-Gonzalez Consejo Nacional de Ciencia y Tecnología-División de Materiales Avanzados Instituto Potosino de Investigación Científica y TecnológicaSan Luis Potosí78216México División de Ciencias e Ingenierías Universidad de GuanajuatoLeón 37150México Grupo de Espectroscopia de Materiales Avanzados y Nanoestructurados(GEMANA) Centro de Investigaciones enópticaA.C.Lomas Del CampestreLeón 37150México

We present the structural,morphological and photocatalytic properties of stretchable composites made with carbon nanotubes (CNTs),silicon rubber and Ni@TiO_(2):W nanoparticles(TiWNi NPs) with average size of 37±2 nm.Microscopy images showed that the TiWNi NPs decorated the surface of the CNT fibers,which are oriented in a preferential direction.TiWNi NPs presented a mixture of anatase/rutile phases with cubic structure.The performance of the TiWNi powders and stretchable composites was evaluated for the photocatalytic degradation of diclofenac (DCF) anti-inflammatory drug under ultraviolet-visible light.The results revealed that the maximum DCF degradation percentages were 34.6%,91.9%,97.1%,98.5%and 100%for the CNT composite (stretched at 0%),TiWNi powders,CNT+TiWNi(stretched at 0%),CNT+TiWNi (stretched at 50%) and CNT+TiWNi (stretched at 100%),respectively.Thus,stretching the CNT+TiWNi composites was a good strategy to enhance the DCF degradation percentage from 97.1%to 100%,since stretching created additional defects (oxygen vacancies) that acted as electron sink,delaying the electron-hole recombination,and favors the DCF degradation.Raman/absorbance measurements confirmed the presence of such defects.Moreover,the reactive oxygen species (ROS) were determined by the scavenger’s experiments and found that the main ROS were the·OH and O_(2)-radicals,which attacked the DCF molecules,causing their degradation.The results of this investigation confirmed that the stretchable CNT/TiWNi-based composites are a viable alternative to remove pharmaceutical contaminants from water and can be manually separated from the decontaminated water,which is unviable using photocatalytic powders.

关键词： Diclofenac Pharmaceutical contaminant TiO_(2) Carbon nanotubes Stretchable composite Photocatalysis