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Implementation of a Nickel-Electroless Coating in Heat Exchanger Pipes Considering the Problem of the Environmental Conditions ofthe Cooling Water Without Recirculation to Increase the Effectiveness Under Uncertainty

VICTOR MANUEL ZEZATTI FLORES GUSTAVO URQUIZA BELTRAN MIGUEL ANGEL BASURTO PENSADO LAURA LILIA CASTRO GOMEZ JUAN CARLOS GARCIA CASTREJON (2022, [Artículo])

This research is based on the operation tube heat exchangers, their use and problematic on hydroelectric power plants. It is based on the design heat exchanger tubes for industrial use, which took the parameters of operation, design, working fluids (air and water) and conditions to assemble a monitoring equipment at appropriate scale for the laboratory, with the necessary measurement instruments to analyze the behavior of heat energy transfer by means of thermocouples, the velocity of the air with a hot wire anemometer and the flow of water with a turbine flow meter, in pipes of different materials: copper, steel 1018 and stainless steel 316L, all in ideal conditions, and with this to found a comparative parameter with pipes of the same materials but under conditions of deterioration with the presence of forced oxidation and with the data mining and support vector machine can be minimized the corrosion problems in pipes.

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS Data mining, Support Vector Machine, Pattern Recognition and Decision Support System, Heat exchangers

Evaluación de la cinética de liberación de compuestos hidrofílicos y lipofílicos a partir de nanopartículas híbridas polímero-lípido

Evaluation of the release kinetics of hydrophilic and lipophilic compounds from polymer-lipid hybrid nanoparticles

Juan Pablo Carmona Almazán (2023, [Tesis de maestría])

En el tratamiento de enfermedades, la administración de dosis múltiples es una estrategia común para mantener la concentración de los fármacos dentro de un margen terapéutico. Sin embargo, la adherencia de los pacientes a este tipo de tratamiento puede ser un desafío, llevando a una administración irregular de dosis. Una alternativa utilizada para abordar este reto son las nanopartículas híbridas polímero/lípido(NPPLs), las cuales, con menos administraciones, tienen el potencial de alcanzar la dosis necesaria en el tratamiento, posibilitando entonces el incremento del apego al tratamiento. En nuestro proyecto, se llevó a cabo la síntesis de nanopartículas de ácido poli láctico-co-glicólico (PLGA) recubiertas de lecitina de soya, por medio de técnicas de nanoprecipitación y autoensamblaje. Además, integramos estas nanopartículas en una matriz polimérica a base de aerogeles de gelatina de manera que estuvieran distribuidas de manera homogénea y concentrada. Nuestro enfoque central radica en entender la cinética de liberación de un compuesto hidrofílico (ácido gálico) y uno lipofílico (quercetina) a partir de este sistema. Logramos sintetizar nanopartículas con un diámetro hidrodinámico de 100 ± 15 nm, 153 ± 33 y149±21 nm, en el caso de las nanopartículas vacías y cargadas con ácido gálico y cargadas con quercetina, respectivamente. La eficiencia de encapsulación del ácido gálico fue del 90 ± 5 % y de la quercetina fue del 70 ± 10 %. Los resultados que obtuvimos muestran que el ácido gálico sigue una cinética del modelo de Korsmeyer-Peppas, con un valor de n = 1.01 y la quercetina una cinética de primer orden. Dado que los compuestos encapsulados tuvieron una liberación más lenta con respecto a los compuestos libres en los aerogeles de gelatina, nuestro trabajo indica que el encapsulamiento en NPPLs de un compuesto bioactivo, independientemente de su naturaleza química, puede ayudar a retrasar su liberación y reducir el número de dosis administradas, en consecuencia, esto pudiera contribuir a incrementar el apego de un paciente al tratamiento.

In the treatment of diseases, the administration of multiple doses is a common strategy to maintain drug concentrations within a therapeutic range. However, patient adherence to this type of treatment can be challenging, resulting in irregular dosing. An alternative approach used to address this challenge involves polymer/lipid hybrid nanoparticles (NPPLs), which have the potential to achieve the necessary drug dose with fewer administrations, thereby increasing treatment adherence. In our project, we synthesized poly(lactic-co-glycolic acid) (PLGA) nanoparticles coated with soy lecithin using nanoprecipitation and self-assembly techniques. These nanoparticles were then integrated into a polymer matrix based on gelatin aerogels to ensure homogeneous and concentrated distribution. Our main focus was to understand the release kinetics of a hydrophilic compound (gallic acid) and a lipophilic one (quercetin) from this system. We successfully synthesized nanoparticles with a hydrodynamic diameter of 100 ± 15 nm, 153 ± 33 nm, and 149 ± 21 nm for empty nanoparticles, gallic acid-loaded, and quercetin-loaded nanoparticles, respectively. The encapsulation efficiency was 90 ± 5 % for gallic acid and 70 ± 10 % for quercetin. The results we obtained indicate that gallic acid follows Korsmeyer-Peppas kinetics with a value of n = 1.01, while quercetin exhibits first-order kinetics. Since the encapsulated compounds showed slower release compared to free compounds in gelatin aerogels, our work suggests that encapsulation in NPPLs with a bioactive compound, regardless of its chemical nature, can help delay its release and reduce the number of doses administered. Consequently, this could contribute to improve patient treatment adherence.

nanopartículas híbridas, cinética de liberación, sistemas poliméricos, PLGA/lecitina, compuestos hidrofílicos y lipofílicos hybrid nanoparticles, release kinetics, polymeric systems, PLGA/lecithin, hydrophilic and lipophilic compounds INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS INGENIERÍA Y TECNOLOGÍA QUÍMICAS ANÁLISIS DE POLÍMEROS ANÁLISIS DE POLÍMEROS

Hot Extremes and Climatological Drought Indicators in the Transitional Semiarid-Subtropical Region of Sinaloa, Northwest Mexico

OMAR LLANES CARDENAS OSCAR GERARDO GUTIERREZ RUACHO Iván Hernández Romano ENRIQUE TROYO DIEGUEZ (2022, [Artículo])

"The main goal of this study was to explore the historical and recent spatial concurrence between the frequency (F), duration (D) and intensity (I) of hot extremes (HEs) and the frequency and evolution of meteorological drought in the region of Sinaloa. Based on the values of daily maximum temperatura (Tmax) and precipitation obtained from CLImate COMputing for the interval April–October of a historical period (1963–2000) and a recent period (1982–2014), the HE and the standardized precipitation index (SPI) were calculated on one-month (SPI-1) and four-month (SPI-4) timescales. Spearman rank correlation coefficients (Sr) were used to obtain the significant concurrences (SCs) between HEs and SPI-1, and HEs and SPI-4. El Quelite weather station showed the highest historical SCs between HEs and SPI-1 (−0.66≤Sr≤−0.57). Jaina is the only station that showed SCs with all four indicators of HEs and SPI-4 (−0.47≤Sr≤−0.34). In this study, the concurrence between HEs and SPI-1, and HEs and SPI-4 was determined for the first time. These are phenomena that can decrease the crop yield, particularly for rainfed crops such as maize, sesame and sorghum in the region commonly known as “the breadbasket of Mexico."

frequency and evolution of meteorological droughts, the breadbasket of Mexico, Sinaloa CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO CLIMATOLOGÍA CLIMATOLOGÍA REGIONAL CLIMATOLOGÍA REGIONAL

Molecular modeling simulation studies reveal new potential inhibitors against HPV E6 protein

Joel Ricci-Lopez (2019, [Artículo])

High-risk strains of human papillomavirus (HPV) have been identified as the etiologic agent of some anogenital tract, head, and neck cancers. Although prophylactic HPV vaccines have been approved; it is still necessary a drug-based treatment against the infection and its oncogenic effects. The E6 oncoprotein is one of the most studied therapeutic targets of HPV, it has been identified as a key factor in cell immortalization and tumor progression in HPV-positive cells. E6 can promote the degradation of p53, a tumor suppressor protein, through the interaction with the cellular ubiquitin ligase E6AP. Therefore, preventing the formation of the E6-E6AP complex is one of the main strategies to inhibit the viability and proliferation of infected cells. Herein, we propose an in silico pipeline to identify small-molecule inhibitors of the E6-E6AP interaction. Virtual screening was carried out by predicting the ADME properties of the molecules and performing ensemble-based docking simulations to E6 protein followed by binding free energy estimation through MM/PB(GB)SA methods. Finally, the top-three compounds were selected, and their stability in the E6 docked complex and their effect in the inhibition of the E6-E6AP interaction was corroborated by molecular dynamics simulation. Therefore, this pipeline and the identified molecules represent a new starting point in the development of anti-HPV drugs. © 2019 Ricci-López et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

ligand, luteolin, protein E6, protein inhibitor, ubiquitin protein ligase, ubiquitin protein ligase E6AP, unclassified drug, antivirus agent, DNA binding protein, E6 protein, Human papillomavirus type 18, oncoprotein, protein binding, protein p53, TP CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Los seres alados y solares del arte maya en el Norte de Yucatán

Rubén Morante (2023, [Capítulo de libro])

En nuestro trabajo de campo en el norte de Yucatán estudiamos la iconografía de sitios como Chichén Itzá, Ek Balam y Mayapán. En ellos observamos esculturas con gran calidad artística de seres humanos que portan alas y que, por ello, se presentan como seres celestes relacionados con deidades del panteón maya de los periodos Clásico tardío, Clásico terminal y Posclásico temprano. Para esta investigación partimos de un breve contexto etnohistórico, geográfico y arqueológico de otros sitios mayas, del centro y oriente de México, incluyendo imágenes de códices y pinturas que nos hablan del posible significado que las plumas, las alas y las aves tuvieron en Mesoamérica. Procedimos al análisis de las figuras aladas que se presentan en relación con importantes edificios de sitios del norte de Yucatán. La advocación solar que sugieren parece haber sido común y en esta zona, no sólo hablan de los grandes artistas que los esculpieron, sino de un sistema de creencias que pudo emanar de tradiciones mayas muy tempranas, que en el siglo IX d.C. se manifiesta de manera clara mediante un estilo depurado, una maestría técnica y una alta sensibilidad estética.

In our field work in northern Yucatán we studied the iconography of sites such as Chichén Itzá, Ek Balam, and Mayapán. There we saw great artistic quality sculptures of human beings that carry wings, and because of that we think that represented celestial beings related to deities of the Mayan pantheon of Late Classic, Terminal Classic and Early Postclassic periods. In our research we started with reviews of ethnohistorical, geographical and archaeological contexts in other Mayan sites, from central and eastern Mexico, including images from codices and paintings that tell us about the possible meaning of feathers, wings and birds in Mesoamerica. We proceeded analyze winged figures presented in relation to important buildings in northern Yucatán sites. Solar evocation suggested probably was common in this area and, sculptures not only speak about belief systems that could emanate from very early Mayan traditions, but also speak about great artists, that in 9th century AD. clearly manifested it through a refined style, technical mastery and high aesthetic sensitivity.

Arte maya, seres alados, Norte de Yucatán, Chchén Itzá, Ek Balam. Mayan art, feathers and birds, Northern Yucatán. Maya art--Themes, motives. Maya arts--Mexico--Yucatán (State) Maya sculpture--Themes, motives. Maya mythology. Arte maya. Mitología maya. F1435.3.A7 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA DE LAS BELLAS ARTES

Multiple approaches to understanding the taxonomic status of an enigmatic new scorpion species of the genus Tityus (Buthidae) from the biogeographic island of Paraje Tres Cerros (Argentina)

Andres Alejandro Ojanguren Affilastro (2017, [Artículo])

Tityus curupi n. sp., belonging to the bolivianus complex, is described from the biogeographically distinct area of Paraje Tres Cerros in north-eastern Argentina. We also present a molecular species delimitation analysis between Tityus curupi n. sp. and its sister species Tityus uruguayensis Borelli 1901 to confirm species integrity. Furthermore, a cytogenetic analysis is presented for these two species which contain different multivalent associations in meiosis, as a consequence of chromosome rearrangements, and the highest chromosome numbers in the genus. © 2017 Ojanguren-Affilastro et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Argentina, chromosome analysis, chromosome rearrangement, genus, human, meiosis, sister, species, anatomy and histology, animal, Argentina, chemistry, chromosome, classification, ecosystem, fluorescence in situ hybridization, genetics, geography, isl BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA DE INSECTOS (ENTOMOLOGÍA) BIOLOGÍA DE INSECTOS (ENTOMOLOGÍA)

Contrabando y redes de negocios : Hispanoamérica en el comercio global, 1610-1814

Guillermina del Valle Pavón (2023, [Libro])

"Las colaboraciones que integran este libro colectivo profundizan en el análisis de algunos circuitos comerciales, que fueron claves en el juego de intercambios en Nueva España, Perú, las Filipinas, La Habana y Buenos Aires, en el arco temporal que se extiende de 1610 a 1814."

Hispanoamérica (Antiguo Régimen); Nueva España (Virreinato); Comercio; Comercio mundial; Comerciantes; Contrabando; Corrupción; Empresas; Mercantilismo; Monarquía hispánica; Mercaderes; Redes de negocios; Argentina; Estudios de caso; Siglos XVII-XIX; CIENCIAS SOCIALES HISTORIA HISTORIA POR ESPECIALIDADES HISTORIA POR ESPECIALIDADES

Effect of antimicrobial nanocomposites on Vibrio cholerae lifestyles: Pellicle biofilm, planktonic and surface-attached biofilm

ANAID MEZA VILLEZCAS (2019, [Artículo])

Vibrio cholerae is an important human pathogen causing intestinal disease with a high incidence in developing countries. V. cholerae can switch between planktonic and biofilm lifestyles. Biofilm formation is determinant for transmission, virulence and antibiotic resistance. Due to the enhanced antibiotic resistance observed by bacterial pathogens, antimicrobial nanomaterials have been used to combat infections by stopping bacterial growth and preventing biofilm formation. In this study, the effect of the nanocomposites zeolite-embedded silver (Ag), copper (Cu), or zinc (Zn) nanoparticles (NPs) was evaluated in V. cholerae planktonic cells, and in two biofilm states: pellicle biofilm (PB), formed between air-liquid interphase, and surface-attached biofilm (SB), formed at solid-liquid interfaces. Each nanocomposite type had a distinctive antimicrobial effect altering each V. cholerae lifestyles differently. The ZEO-AgNPs nanocomposite inhibited PB formation at 4 μg/ml, and prevented SB formation and eliminated planktonic cells at 8 μg/ml. In contrast, the nanocomposites ZEO-CuNPs and ZEO-ZnNPs affect V. cholerae viability but did not completely avoid bacterial growth. At transcriptional level, depending on the nanoparticles and biofilm type, nanocomposites modified the relative expression of the vpsL, rbmA and bap1, genes involved in biofilm formation. Furthermore, the relative abundance of the outer membrane proteins OmpT, OmpU, OmpA and OmpW also differs among treatments in PB and SB. This work provides a basis for further study of the nanomaterials effect at structural, genetic and proteomic levels to understand the response mechanisms of V. cholerae against metallic nanoparticles. © 2019 Meza-Villezcas et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

bacterial protein, copper nanoparticle, nanocomposite, OmpT protein, OmpU protein, OmpW protein, outer membrane protein A, silver nanoparticle, unclassified drug, zeolite, zinc nanoparticle, antiinfective agent, copper, metal nanoparticle, nanocompos BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA

Waterhole detection using a vegetation index in desert bighorn sheep (Ovis canadensis cremnobates) habitat

Jonathan Gabriel Escobar Flores (2019, [Artículo])

In arid ecosystems, desert bighorn sheep are dependent on natural waterholes, particularly in summer when forage is scarce and environmental temperatures are high. To detect waterholes in Sierra Santa Isabel, which is the largest area of desert bighorn sheep habitat in the state of Baja California, Mexico, we used the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) from Sentinel-2 satellite images. Waterhole detection was based on the premise that sites with greater water availability, where NDVI was higher, can be identified by their density of vegetation greenness. For the detected waterholes, we estimated the escape terrain (presence of cliffs or steep, rocky slopes) around each by the vector ruggedness measure to determine their potential use by desert bighorn sheep based on the animals’ presence as documented by camera traps. We detected 14 waterholes with the NDVI of which 11 were known by land owners and 3 were unrecorded. Desert bighorn were not detected in waterholes with high values of escape terrain, i.e., flat areas. Waterhole detection by NDVI is a simple method, and with the assistance and knowledge of the inhabitants of the Sierra, it was possible to confirm the presence each waterhole in the field. © 2019 Escobar-Flores et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, bighorn sheep, environmental aspects and related phenomena, environmental parameters, habitat, Mexico, nonhuman, normalized difference vegetation index, normalized difference water index, water availability, waterhole, animal, bighorn sheep, CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CIENCIA FORESTAL

Rapid effects of marine reserves via larval dispersal

Richard Cudney Bueno (2009, [Artículo])

Marine reserves have been advocated worldwide as conservation and fishery management tools. It is argued that they can protect ecosystems and also benefit fisheries via density-dependent spillover of adults and enhanced larval dispersal into fishing areas. However, while evidence has shown that marine reserves can meet conservation targets, their effects on fisheries are less understood. In particular, the basic question of if and over what temporal and spatial scales reserves can benefit fished populations via larval dispersal remains unanswered. We tested predictions of a larval transport model for a marine reserve network in the Gulf of California, Mexico, via field oceanography and repeated density counts of recently settled juvenile commercial mollusks before and after reserve establishment. We show that local retention of larvae within a reserve network can take place with enhanced, but spatially-explicit, recruitment to local fisheries. Enhancement occurred rapidly (2 yrs), with up to a three-fold increase in density of juveniles found in fished areas at the downstream edge of the reserve network, but other fishing areas within the network were unaffected. These findings were consistent with our model predictions. Our findings underscore the potential benefits of protecting larval sources and show that enhancement in recruitment can be manifested rapidly. However, benefits can be markedly variable within a local seascape. Hence, effects of marine reserve networks, positive or negative, may be overlooked when only focusing on overall responses and not considering finer spatially-explicit responses within a reserve network and its adjacent fishing grounds. Our results therefore call for future research on marine reserves that addresses this variability in order to help frame appropriate scenarios for the spatial management scales of interest. © 2009 Cudney-Bueno et al.

article, environmental monitoring, fishery, larva, marine environment, marine species, Mexico, mollusc, nonhuman, oceanography, prediction, animal, biology, environmental protection, food industry, geography, growth, development and aging, larva, met CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA