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Rafael Cerón,1,2 Adolfo Martínez,2 Christian Ramos,3 Adrián De la Cruz,2 Anel García,2 Iveth Mendoza,2 Goujon Palmeros,2 Efreen Horacio Montaño Figueroa,3 Juan Navarrete,4 Silvia Jiménez-Morales,5 Carlos Martinez-Murillo,3 Irma Olarte2 1Posgrado en Ciencias Biológicas, Biomedicina, UNAM, CDMX, México; 2Department of Molecular Biology, Hematology Service, Hospital General de México, “Dr. Eduardo Liceaga”, Mexico City, Mexico; 3Department of Medical Hematology, Hospital General de México, “Dr. Eduardo Liceaga”, Mexico City, Mexico; 4Department of Hematopathology, Hospital General de México, “Dr. Eduardo Liceaga”, Mexico City, Mexico; 5Laboratory of Cancer Genomics, National Institute of Genomic Medicine, Mexico City, MexicoCorrespondence: Irma Olarte, Dr. Balmis 148, Col. Doctores, Alc. Cuauhtémoc, Mexico City, ZC. 06726, Mexico, Tel +525527892000 Ext. 1609, Email irmaolartec@yahoo.comPurpose: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous malignant lymphoid neoplasm and is the most common subtype of non-Hodgkin lymphoma in adults. More than half of patients with DLBCL can achieve remission with standard R-CHOP regimes; however, approximately 30– 40% of patients are still failing this standard therapy, which remains as an important cause of progression and mortality of this disease. It is necessary to have diagnostic and monitoring tools that allow us to improve the accuracy of prognosis in these patients. Circulating tumor cells (CTCs) identification through molecular biomarkers is one of the novel strategies that have been used in other types of cancer, and we aim to use this tool to analyze the potential role in DLBCL.Patients and Methods: We analyzed 138 blood samples of patients with DLBCL, of which CTCs were isolated by density gradient for subsequent detection and quantitation of molecular biomarkers using RT-qPCR with TaqMan probes. Survival analysis was performed using Kaplan–Meier curves.Results: We found overexpression of ABCB1, αSMA, BCL2, BCL6 and VEGFR1 genes, as well as the presence of CK19, EpCAM, KI67, MAGE-A4, SNAIL and TWIST1 genes. CK19 and EpCAM expression were associated with a minor OS (85.7% vs 98.1%, p = 0.002). The overexpression of BCL2, BCL6, VEGFR1 and TWIST1 was related to a minor EFS (p = 0.001).Conclusion: This study showed that in liquid biopsies analyzed, the presence of CTCs can be confirmed through molecular biomarkers, and it has an impact on OS and EFs, making this detection useful in the follow-up and prognosis of patients with DLBCL.Keywords: biomarkers, CTCs, lymphoma, liquid biopsies

Reportes de mordeduras por tarántulas a humanos son raros. La tarántula es una araña venenosa de la familia Theraphosidae, habitante común en regiones tropicales. La severidad del envenenamiento depende de la especie y tamaño que puede variar de dolor leve a intenso, edema localizado y espasmos musculares. Presentamos un caso de mordedura de tarántula en la selva Amazónica del Ecuador. Mujer de 35 años, mordida en el tercer dedo de la mano derecha, mientras realizaba actividades domésticas. Presenta dolor intenso, limitación de movimientos, eritema, calor y edema del dedo y mano afectada. Valores de la biometría hemática dentro de rangos normales. Se administró ketorolaco y dexametasona con mejoría en 24 horas. Es importante reportar estos casos que son frecuentes en las zonas rurales tropicales, por su desconocimiento pueden ser mal manejados; recomendamos el registro en las estadísticas nacionales y la colaboración de entomólogos para la identificación a nivel de especie.

A set of Y-type zeolites with Si/Al atomic ratios between 7–45 were studied as catalysts in the aminocyclization reaction between acrolein and ammonia to produce pyridine and 3-picoline. The catalytic activity tests at 360 °C revealed that the acrolein conversion increased in the order Z45 < ZY34 < ZY7 < ZY17, in agreement with the increase of the total acidity per gram of catalyst. In all cases, pyridine bases and cracking products (acetaldehyde and formaldehyde) were detected in the outflow from the reactor. The total yield of pyridines was inversely proportional to the total acidity for the catalysts, which presented large surface areas and micro- and mesoporosity. The selectivity towards 3-picoline was favored when using catalysts with a Brønsted/Lewis acid sites ratio close to 1. The formation of pyridine occurred more selectively over Lewis acid sites than Brønsted acid sites. The deactivation tests showed that the time on stream of the catalysts depended on the textural properties of zeolites, i.e., large pore volume and large BET area, as evidenced by the deactivation rate constants and the characterization of the spent catalysts. The physicochemical properties of the catalysts were determined by XRD, UV-vis, and Raman spectroscopies, infrared spectroscopy with adsorbed pyridine, N2 physisorption, and SEM-EDXS. After the reaction, the spent catalysts were characterized by XRD, Raman spectroscopy, TGA, and SEM-EDXS, indicating that the uniform deposition of polyaromatic species on the catalyst surface and within the porous system resulted in the loss of activity.

House-screening (HS) using fixed-aluminium frames to reduce the risk of indoor infestation with Aedes aegypti mosquitoes as well as the risk of Aedes-transmitted diseases in communities living in endemic areas. However, the success of this approach has been hindered by the elevated cost of the aluminium-based materials as well as their professional installation, which cannot be afforded by people living under vulnerable conditions. Cost-saving strategies such as the use of low-cost materials including wood, PVC, and Velcro are within the list of HS options available and offered by HS businesses and/or Do-it-yourself (DIY) packages verbi gratia ready-made and ready-to-install mosquito-screens. Here, we evaluated the efficacy of low-cost frames constructed with different materials to protect against Ae. aegypti indoor infestation using experimental huts. The efficacy of protection in preventing female mosquito passing inside the huts of any of the options of frames was high (>93%) compared to the control with no-screen. People’s perceptions on the different materials showed the most “popular” alternative was the frame made of wood (62%). All the prototype-frames of HS made of different materials were effective at blocking Ae. aegypti entering-mosquitoes particularly, low-cost options like magnets and Velcro.

After the tropical storm Cristobal, we performed special adult entomological collections in the peri-domicile of 35 houses from 25 neighborhoods of Merida, Yucatan, Mexico in response to complaints from the community about an increased nuisance due to an abundance of mosquitoes. A total of 1,275 specimens from four genera and 13 species were collected: Aedes taeniorhynchus (92%), Culex quinquefasciatus (72%), Aedes aegypti (72%), Psorophora mexicana (36%), Psorophora cyanescens (32%), Aedes scapularis (24%), Culex nigripalpus (24%), Aedes albopictus (8%), Psorophora ferox (4%), Haemagogus equinus (4%), Aedes trivittatus (4%), Culex coronator (4%), Culex iolambdis (4%). From these collections, the increased mosquito nuisance was mainly the result of invasive species such as Aedes taeniorhynchus and Psorophora. City wide, vehicle mounted ULV spraying was performed by the MoH and the municipality of Merida to control adult mosquito populations. We report Culex iolambdis for the first time in Merida and Psorophora mexicana for the state of Yucatan.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous malignant lymphoid neoplasm and is the most common subtype of non-Hodgkin lymphoma in adults. More than half of patients with DLBCL can achieve remission with standard R-CHOP regimes; however, approximately 30-40% of patients are still failing this standard therapy, which remains as an important cause of progression and mortality of this disease. It is necessary to have diagnostic and monitoring tools that allow us to improve the accuracy of prognosis in these patients. Circulating tumor cells (CTCs) identification through molecular biomarkers is one of the novel strategies that have been used in other types of cancer, and we aim to use this tool to analyze the potential role in DLBCL.We analyzed 138 blood samples of patients with DLBCL, of which CTCs were isolated by density gradient for subsequent detection and quantitation of molecular biomarkers using RT-qPCR with TaqMan probes. Survival analysis was performed using Kaplan-Meier curves.We found overexpression ofThis study showed that in liquid biopsies analyzed, the presence of CTCs can be confirmed through molecular biomarkers, and it has an impact on OS and EFs, making this detection useful in the follow-up and prognosis of patients with DLBCL.

We report results of susceptibility tests for Aedes taeniorhynchus from 2 localities of Yucatan State, Mexico, to different insecticides. The Centers for Disease Control and Prevention bottle bioassays were performed using the active ingredients of 3 pyrethroids, 2 organophosphates, and 1 carbamate: permethrin (15 μg/ml), deltamethrin (10 μg/ml), alpha-cypermethrin (10 μg/ml), malathion (50 μg/ml), chlorpyrifos (85 μg/ml), and bendiocarb (12.5 μg/ml). The mortality recorded at the diagnostic time of exposure (30 min) was 100% with all insecticides evaluated and for both populations. These results suggest complete susceptibility to the 3 chemical groups generally used for urban Ae. aegypti mosquito control.

espanolEste articulo muestra que Chile experimento una profunda transicion nutricional en un corto periodo de tiempo. Antes de comienzos de los anos 1990, la mayoria de los chilenos tenia una dieta pobre en calcio y proteina animal. Hoy, sin embargo, los chilenos disfrutan de una dieta caracterizada por un alto consumo de carne y productos lacteos. El aumento subito en el consumo de carnes y productos lacteos esta principalmente asociado a la adopcion en Chile de la revolucion internacional en agronegocios; al apoyo gubernamental entre las decadas de 1930 y 1960; a un aumento del PIB per capita; la estabilidad macroeconomica; los cambios en habitos de consumo; la liberalizacion comercial; y a la caida de precios de los alimentos, que tienen una alta elasticidad de demanda. Estas revoluciones en produccion y consumo han mejorado de gran manera la nutricion de la poblacion chilena, lo que explica parte de las mejoras en bienestar biologico del pais. EnglishThis article shows how Chile experienced a profound nutrition transition within a short period of time. Before the early 1990s, the diet of most Chileans was poor in animal proteins and calcium. Today, Chileans enjoy a diet characterized by high consumption of meat and dairy products. The rapid rise in consumption of these products can be attributed to various factors: Chile belatedly joining the international agribusiness revolution; government support from the 1930s to the 1960s; increasing GDP per capita; macro-economic stability; changes in consumption habits; trade liberalization; and the fall in food prices, as both meat and milk had high income elasticity. These revolutions in both production and consumption have greatly improved the nutrition of the Chilean population and partly explain the improvement in Chile’s biological well-being.

Este artí­culo estudia la posición de Chile dentro de las redes mundiales de cobre entre 1700 y la década de 1840. Durante este periodo, los niveles de producción eran bajos, si se los compara con los de 1850-1870 y el siglo XX, debido tanto a las pobres técnicas de extracción y refinado como a los altos costos de transporte. Sin embargo, el cobre chileno fue consumido dentro de Chile, en mercados cercanos como Perú, Bolivia y Argentina, y también se exportó a España, a otros paí­ses de Europa, así­ como a Asia. En esta época, el cobre chileno se habí­a internacionalizado, pero no globalizado. Fue después de la independencia que el cobre chileno comenzó a fluir más libremente a Asia, mientras que los Estados Unidos y Europa continental se convirtieron, también, en mercados claves. Durante este periodo, no solo se exportaba cobre fundido, sino que también regulus y mineral de cobre. Fue solo el arribo de mercantes banqueros británicos a Chile, como Huth & Co., lo que permitió una verdadera globalización del cobre chileno, tal como muestran los archivos de esta compañí­a.

Two series of FeOx/SBA-15 and FeOx/Zr-SBA-15 mesoporous catalysts were synthesized with ultrasound-assisted method by varying Fe content from 10 wt% to 20 and 30 wt%. The crystalline structure, textural properties, surface morphologies, surface acidity, and phase composition of the catalysts were characterized by X-ray diffraction (XRD), N2 adsorption–desorption isotherm, scanning electron microscopy (SEM), transmission electron microscopy (TEM), in situ Fourier transform infrared spectroscopy (FTIR). The XRD, Raman and Mossbauer spectroscopic characterizations showed that both γ-Fe2O3 and α-Fe2O3 nanoparticles were present in all the catalysts and Fe3+ ions were dispersed on the surface of SBA-15 with different coordination. In the oxidation desulfurization (ODS) of a model diesel, the reaction parameters (temperature, time, and catalyst mass), Fe content, zirconium doping, and surface acidity of the catalysts were all critical for the ODS in a biphasic reaction system. All catalysts chiefly contained Lewis acidity which was related to iron content and zirconium modification and could correlate well with catalytic activity. Zirconium incooperating into the SBA-15 solid increased surface acidity and promoted γ-Fe2O3 formation by inhibiting the amorphous iron oxide in the Fe/Zr-SBA-15 catalysts, thus improved the ODS efficiency. The reaction temperature 60 °C was the optimal for ODS reaction, temperature greater than 80 °C led to oxidant partial decomposition. Under the optimal reaction condition, 0.1 g of the best catalysts (30%Fe/SBA-15 and 30%Fe/Zr-SBA-15) could remove all dibenzothiophene (DBT) (300 ppm DBT in 100 ml n-hexadecane) at 60 °C within 30 min. Thus, the combination of catalysis, oxidation and extraction in our polar-nonpolar-solid reaction system was simultaneously realized in one unit, which will be promising for effectively removal of organosulfur compounds for production of ultralow sulfur fuels.

We provide the first estimates of gender income and land inequality in Chile during the first decades after independence, when Chile was a predominantly agrarian society. We have used a new source: the records of the first agricultural censuses ever made for any Latin American republic. We found that there were over six times more male landowners than women, and that male owners gathered up to 87% of total agricultural income (of those paying the catastro ). On the positive side, we found that female landownership was more widespread than has previously been assumed by Chilean historians, although it was declining in relative terms. We have also identified the main elite women agrarian entrepreneurs, finding that one of the biggest landowners of this period was a woman, who has been ignored in the historiography. We have documented her economic activities, as well as those of many other prominent women agricultural entrepreneurs, thus showing that women’s involvement in crucial entrepreneurship activities started earlier than previously been acknowledged, from colonial times.

Resumen: Este artículo analiza la distribución del ingreso agrícola y de la tierra en Chiloé entre c.1830 y los años 1850, comparando ambas variables con el resto de las provincias chilenas, en un periodo insuficientemente tratado en la literatura especializada. Para ello hemos empleado información procedente de fuentes escasamente utilizadas en la historiografía agraria, especialmente el Catastro Agrícola. A partir del mismo, hemos construido y procesado una base de datos de más de medio millón de registros provenientes de los tres primeros catastros agrícolas, realizados en 1832, 1837 y 1852. Nuestros resultados indican que la distribución tanto del ingreso agrícola como de la tierra en Chiloé era muy igualitaria, lo que constituye una excepción dentro de todas las provincias chilenas c.1830-1855. Esta excepcionalidad de la sociedad rural de Chiloé se explica principalmente por políticas aplicadas desde fines del periodo colonial, en particular la entrega de tierras a criollos e indígenas, así como por un proceso de partición y venta de tierras realizado poco después de la independencia, un fenómeno único en Chile.

The study of the deactivation of HY zeolites in the dehydration reaction of glycerol to acrolein has represented a challenge for the design of new catalysts. HY zeolites with SiO2/Al2O3 molar ratios between 3.5 and 80 were studied. The solids were characterized by XRD, N2 physisorption, SEM-EDXS, Raman and UV-vis spectroscopies, infrared spectroscopy of pyridine (FTIR-Py) and catalytic activity tests from 250 °C to 325 °C. It was found that the total amount of acid sites per unit area of catalyst decreased as the SiO2/Al2O3 molar ratio increased from 3.5 to 80, resulting in the decrease in the initial glycerol conversion. The initial acrolein selectivity was promoted with the increase of the Brønsted/Lewis acid sites ratio at any reaction temperature. The deactivation tests showed that the catalyst lifetime depended on the pore structure, improving with the presence of large surface areas as evidenced by the deactivation rate constants. The characterization of the deactivated catalysts by XRD, N2 physisorption and thermogravimetric analysis indicated that the deposition of coke resulted in the total obstruction of micropores and the partial blockage of mesopores. Moreover, the presence of large mesopores and surface areas allowed the amount of coke deposited at the catalyst surface to be reduced.

After the tropical storm Cristobal, we performed special adult entomological collections in the peri-domicile of 35 houses from 25 neighborhoods of Mérida, Yucatan, Mexico in response to complaints from the community about an increased nuisance due to an abundance of mosquitoes. A total of 1,275 specimens from four genera and 13 species were collected: Aedes taeniorhynchus (92%), Culex quinquefasciatus (72%), Aedes aegypti (72%), Psorophora mexicana (36%), Psorophora cyanescens (32%), Aedes scapularis (24%), Culex nigripalpus (24%), Aedes albopictus (8%), Psorophora ferox (4%), Haemagogus equinus (4%), Aedes trivittatus (4%), Culex coronator (4%), Culex iolambdis (4%). From these collections, the increased mosquito nuisance was mainly the result of invasive species such as Aedes taeniorhynchus and Psorophora. City wide, vehicle mounted ULV spraying was performed by the MoH and the municipality of Merida to control adult mosquito populations. We report Culex iolambdis for the first time in Merida and Psorophora mexicana for the state of Yucatan.

The adsorption capacities of two synthesized zeolites (crystalline ZSM-5 and semi-crystalline faujasite Y) for a mixture of indole, quinoline and carbazole were studied. The different samples obtained show different crystalline degree, mesoporosity and Si/Al ratios. The synthesis procedure is based on the simultaneous depolymerization of a mixture of high surface area silica, such as rice hull ashes (RHA), and a crystalline zeolite, such as clinoptilolite or faujasite. The depolymerization step is followed by a partial reorganization induced by a structure-directing agent. A model mixture of nitrogenous compounds was prepared, then it was mixed with the zeolite samples and the amount adsorbed of nitrogenous compounds was determined by gas chromatography. Analysis of the adsorbed molecules reveals selectivity in favor of quinoline, followed by indole and then carbazole. The best adsorbent properties correspond to the solid with highest porous volume. The samples obtained were characterized by X-ray diffraction, 29Si and 27Al magic-angle spinning nuclear magnetic resonance, X-ray fluorescence and Fourier transform infrared spectroscopy. The Barrett-Joyner-Halenda (BJH) pore size distribution and the Brunauer-Emmet-Teller (BET) surface area values were obtained from N2 adsorption/desorption isotherms.

Este artículo reza en un análisis lógico jurídico del derecho de defensa y el debido proceso en el proceso penal, exclusivamente en la etapa intermedia, la cual es una de las etapas más técnicas e indispensables en el desarrollo del proceso, así mismo se habla del papel que desempeñan las partes en el proceso penal mexicano durante la audiencia intermedia, de la misma manera aborda la normatividad aplicable para la impartición de justicia y los principios base sobre los cuales se desarrolla el proceso penal.

High levels of sulfur organic compounds (SOCs) and nitrogen organic compounds (NOCs), which are contaminants present in diesel fuel and straight run gas oil (SRGO), were removed using tungsten/zirconia catalysts and hydrogen peroxide by oxidative desulfurization and oxidative denitrogenation reactions. Two tungsten sources were used: tungstic acid and ammonium metatungstate. The catalysts obtained by anionic exchange at low pH with tungstic acid showed remarkable homogeneity and high W dispersion attributed to tetrahedral W species and full dibenzothiophene (DBT) oxidation was achieved in 5 min of reaction. On the other hand, the catalysts obtained by impregnation with ammonium metatungstate developed mainly octahedral species with less DBT oxidation. It was also found that tetrahedral species generate more acidity than octahedral species. A density functional theory computational study confirmed the observed DBT oxidation trend shown by tetrahedral and octahedral W species on the peroxide-activated catalysts. Diesel fuel and SRGO were desulfurized and denitrogenated to a high extent: 97% in diesel fuel and 70% in SRGO for sulfur compounds and 96% in diesel fuel and 89% in SRGO for nitrogen compounds, whereas C1–C3 dibenzothiophenes, 4-methyl dibenzothiophene, and 4,6-dimethyl dibenzothiophene were fully removed. The elimination of SOCs and NOCs present in fuels can be effectively carried out in a single process to obtain clean fuels.

For the first time, highly selective Pt/H 3 PW 12 O 40 /SBA–15 trifunctional catalysts were evaluated for n-heptane hydroisomerization. Both Lewis (L) and Bronsted (B) acid sites were present in these catalysts. Reduction treatment led to heteropolyacid dispersion better and Pt nanoparticles smaller. With the best 1wt%Pt/20wt%H 3 PW 12 O 40 /SBA–15 catalyst, 100% isomerization selectivity and 56.74% n-heptane conversion were obtained at 320 °C. Among the products, the dibranched isomers concentration faction was > 50% and 2,2-dimethylpentane was predominant. Pt/H 3 PW 12 O 40 /SBA–15 catalysts with Pt nanocrystals, proper acidity strength and a balanced ratio of B/L acid sites, and highly ordered large mesopores were chiefly responsible for the high isomerization selectivity.

Alumina-supported Mo-based hydrodesulfurization catalysts (14 wt% nominal Mo loading) were modified by thioglycolic acid (TGA, TGA/Mo = 1 mol ratio), as a chelating agent containing a thiol group. To that end, two series of catalyst were prepared: the first one by using ammonium heptamolybdate as a precursor and, in the second one, in situ obtained phosphomolybdates from MoO 3 digestion in diluted H 3 PO 4 . Oxidic phases were characterized by N 2 physisorption, Raman and UV–vis spectroscopies, electron microscopy and XPS. As well, the corresponding sulfided phases were studied by XPS, HR-TEM-STEM techniques, and chemical composition was determined by STEM-EDX. Formation of ligand-to-metal charge transfer (LMCT) complexes between the S-bearing TGA and Mo atoms, resulted in reduced Mo 5+ species, as indicated by XPS, and was correlated to electronic transitions bands in the UV–visible spectra. On the other hand, the catalysts prepared from phosphomolybdates impregnation and TGA addition resulted in two-fold amount of Mo 4+ sulfided species, as indicated by XPS. TGA impregnation redissolve and disperse the MoO 3 resulting in materials particles in materials with increased stacking of MoS 2 slabs on which slabs length remained essentially unaltered. Highly active (as tested in liquid-phase dibenzothiophene hydrodesulfurization) Type II sites were favored mainly in sulfided TGA-modified formulations.

In this work, the acid and photocatalytic properties of titanate nanotubes (NTs) were surveyed. The surface acidity of the NTs was characterized by FTIR with lutidine and pyridine. The photocatalytic degradation of phenol in aqueous suspension was performed to test the photocatalytic properties of the NTs. The results were compared with those obtained from commercial TiO 2 . NTs were prepared by hydrothermal treatment of TiO 2 nanoparticles in a NaOH aqueous solution. During the washing step, three different acid agents (HCl, H 2 SO 4 , and HNO 3 ) were used. TiO 2 nanoparticles were synthesized previously by the sol-gel method. The photocatalytic materials were characterized by FTIR, XRD, XPS, S BET , UV–vis, and HRTEM. It was found that the used acid agent significantly affected the amount and type of acid sites. Bronsted acid sites were favored by the use of HNO 3 . Lewis acid sites were promoted when HCl was employed during the washing step, which is in contrast with the results obtained using the other acids chosen in this work. Besides, the use of HCl promoted the H 2 Ti 3 O 7 phase. The acid phase H 2 Ti 4 O 9 ·H 2 O was favored when HNO 3 was used and H 2 SO 4 formed the H 2 Ti 2 O 4 ·(OH) 2 acid phase. The presence of Cl, S, and N species on the NTs was not found. Furthermore, Na + ions were completely removed from the surface of the NTs, which were exchanged by H + ions. It was found, in general, that the three catalysts presented a relatively high photocatalytic activity to remove phenol. However, NTs washed with HNO 3 (NT-HNO 3 ) displayed the best photocatalytic activity compared to the other NTs. After 200 min, NT-HNO 3 reached a phenol degradation yield close to 100%. Commercial TiO 2 presented a phenol degradation yield close to 60%. It could be concluded that the acid phase (H 2 Ti 4 O 9 ·H 2 O) and concentration of Bronsted acid sites promoted the photocatalytic activity of NT-HNO 3 .

A survey was carried out to identify the mosquitoes inhabiting human premises in the rural locality of Maxcanú, Yucatán, Mexico. Using the Centers for Disease Control and Prevention backpack aspirators, simple random sampling was carried out inside of 101 homes during the November 2013 rainy season. A total of 1,492 specimens were collected. Three subfamilies (Anophelinae, Culicinae, and Toxorhynchitinae) and 5 species were identified: Anopheles albimanus, Aedes aegypti, Culex interrogator, Limatus durhamii, and Toxorhynchites theobaldi. The most abundant species was Cx. interrogator (74%) followed by Ae. aegypti (25%). The Chao 1 and Bootstrap species richness estimator indicated that it was possible to collect 90% of the expected species. This is the 1st time that the presence of An. albimanus, Cx. interrogator, Li. durhamii, and Tx. theobaldi has been recorded in Maxcanú.

V-Mg-Al mixed-oxide catalysts for oxidative dehydrogenation of propane were prepared by thermal decomposition of Mg-Al-layered double hydroxides with vanadium interlayer doping. The obtained catalysts were tested for the oxidative dehydrogenation of propane, obtaining good results in catalytic activity (conversion 16.55 % and selectivity 99.97 %). Results indicated that catalytic performance of these materials depends on how vanadium is integrated in the layered structure, which is determined by the Mg/Al ratio. Vanadium interlayer doping modifies the oxidation state of vanadium and consequently catalytic properties. Surface properties were studied by X-ray photoelectron spectroscopic and diffuse reflectance, UV-visible spectroscopy, and temperature programmed reduction (TPR). The analyses provided information about the oxidation state, before and after the reaction. From these results, it is suggested that selectivity to propylene and catalytic activity depend mainly on vanadium oxidation state.

This work reports the results of the ultrasound-assisted hydrothermal synthesis of two sets of V2O5 dispersed on SBA-15 and Zr doped SBA-15 catalysts used for the oxidation of dibenzothiophene (DBT) in a model diesel via the combination of oxidation, catalysis, and extraction technical route. These catalysts contained Lewis acidity as major and Brønsted acidity as minor. The amount of acidity varied with the content of vanadia and zirconium doping. It was found that DBT conversion is very sensitive to the Lewis acidity. DBT conversion increased by increasing the vanadium content and correlated well with the amount of surface Lewis acidity. Under the optimal experimental condition (Reaction temperature: 60 °C, reaction time 40 min, catalyst concentration: 1 g/L oil, H2O2/DBT mole ratio = 10), the 30% V2O5/SBA-15 and 30% V2O5/Zr-SBA-15 catalysts could convert more than 99% of DBT. Two reaction pathways of DBT oxidation involving vanadia surface structure, Lewis acidity, and peroxometallic complexes were proposed. When the vanadia loading V2O5 ≤ 10 wt%, the oxidative desulfurization (ODS) went through the Pathway I, in the catalysts with moderate vanadia content (V2O5 = 20–30 wt%), ODS proceeded via the Pathways II or/and the Pathway I.

TiO2 nanotubes, nanofibers and nanowires were prepared by the hydrothermal treatment of TiO2 nanoparticles with different NaOH concentrations (5, 10 and 12 N) at 120, 140 and 180 °C; afterwards, HCl was added until reaching pH 2. Both the crystalline phase and coordination of the TiO2 nanotubes, nanofibers and nanowires were composed principally of H2Ti3O7, H2Ti4O9·H2O and H2Ti5O11·H2O. Likewise, the surface area, pore volume and pore size of the TiO2 nanotubes, nanofibers and nanowires changed with the NaOH rinsing treatment. The photocatalytic activities for methylene blue and methyl orange degradation were strongly enhanced by the nanotubes and nanoparticles in the basic and acid media, respectively, showing a relationship between their structure and the medium.

Resumen: La estatura promedio de una población se ha considerado recientemente como un buen indicador de bienestar biológico, y por tanto de niveles de vida y desarrollo económico. Este artículo entrega la primera serie disponible para Chile, aportando la evolución de la estatura promedio de soldados chilenos (varones) nacidos desde la década de 1730 hasta la de 1980, usando una muestra de 6.200 individuos. Dicha muestra puede tomarse como un buen proxy de la estatura promedio de la población chilena (masculina) para el período bajo estudio. Del análisis de los datos, nuestras principales conclusiones son: i) a mediados del siglo XVIII la estatura promedio de los chilenos era relativamente alta si se compara con Chile mismo en otros períodos, así como con otros países de la región y de Europa; ii) en el siglo XIX la estatura promedio de los chilenos cae durante un período prolongado; iii) en el siglo XX se observa un importante aumento de la estatura promedio masculina, aunque en el mundo desarrollado la estatura creció mucho más rápido que en Chile.

espanolEste articulo hace una contribucion al estudio de empresas familiares en economias en desarrollo analizando el caso de la empresa familiar Cousino-Goyenechea, uno de los grupos economicos mas importantes de Chile en el siglo XIX. Presentamos nueva evidencia sobre como se construyo la fortuna inicial de los Cousino, y de como, despues de haber estado altamente concentrada en cobre y plata, el negocio familiar se diversifico de manera exitosa, ademas de integrarse verticalmente a traves de dos generaciones, deviniendo asi en el segundo grupo economico mas importante del pais a fines del siglo XIX. Esto fue resultado de decisiones de negocio arriesgadas, sobre todo el decidir ingresar a la mineria del carbon bajo gran incertidumbre, modernizando la industria, expandiendose a otras actividades como refinado de cobre, produccion de ladrillos y vidrios, plantas hidroelectricas, produccion de vinos, etc. Pero el exito del grupo tambien se debio a una inteligente estrategia de incrementos de capital al crear sociedades anonimas vinculadas al grupo. EnglishThis article makes a contribution to the study of family groups in developing economies by analysing the case of the Cousino-Goyenechea business, one of the most important business groups in nineteenth-century Chile. We provide new evidence of how the Cousino’s original fortune was built, and how after being highly concentrated in copper and silver mining, the family business successfully diversified and integrated vertically through two generations, thus becoming the second most important economic group in the country by the end of the 19th century. This was the result of risky business decisions, particularly after deciding to enter coal mining under much uncertainty, modernising this industry, as well as expanding into copper refining, brick and glass manufacturing, hydroelectric power plants, and wine production. However, their success was also due to a clever strategy of capital increase by creating corporations linked to the group

Resumen Este artículo analiza la situación del sector agropecuario y la composición de la élite agraria en Chile en la primera mitad del siglo XIX, un periodo insuficientemente tratado en la literatura especializada. Para ello hemos empleado información procedente de fuentes escasamente utilizadas en la historiografía agraria, como son El Agricultor y, especialmente, el Catastro Agrícola. A partir de este último, hemos construido y procesado una base de datos de medio millón de registros provenientes de los tres primeros catastros agrícolas, realizados en 1832, 1838 y 1852. Junto con establecer las razones del atraso del sector agrario, y una muy desigual distribución tanto de la propiedad de la tierra como del ingreso agrícola, nuestros resultados indican una notable persistencia de las élites agrarias entre fines de la Colonia y las primeras décadas de Chile independiente, así como una significativa correlación entre la clase de grandes agricultores de mayores ingresos y la élite política. Abstract This article assesses the state of the agrarian sector and the composition of the Chilean agrarian elite during the first half of the nineteenth century, a rather unexplored period in Chile's agrarian historiography. We have used several untapped sources such as the Catastro Agrícola and El Agricultor. From the former we have built and processed a half a million records database. From the former we have built and processed a database consisting of half a million records from the first three agricultural censuses of 1832, 1838 and 1852. We have explained why the agricultural sector was so backwards in Chile, while also established a very unequal distribution of both land tenure and agricultural income. Finally, our results show a great persistence within the composition of the agrarian elites between late colonial times and the first decades of republican Chile, as well as a significant correlation between the large landowners with highest agricultural income and the political elite.

Pt on alumina catalysts were studied when the texture of the alumina change by addition of a cationic surfactant cetyl-trimethyl ammonium bromide (CTAB). The mesoporous alumina was prepared using CTAB from 0.01 to 0.1 M. The surface area and pore volume increased as CTAB concentration increased passing through a maximum. After calcination at 300 °C, and 550 °C boehmite and γ-Al2O3 were found by XRD. After calcination at 800 °C, the transition between γ- and θ-Al2O3 was observed together with an increase of pore volume and pore diameter respect to the alumina without surfactant. The alumina prepared with the lowest concentration of CTAB showed the highest thermal stability. Bronsted and Lewis acidities were found on alumina samples having CTAB concentrations from 0 to 0.075 M. The sample of alumina with the highest CTAB concentration showed the highest population of pentahedral aluminum (AlV), Lewis acidity and a dense network of wormlike particles by SEM. After H2 reduction of these catalysts, sulfur that came from the alumina support weakened the function of Pt particles to hydrogenolysis reaction whereas the CTAB introduced Bronsted acid sites in the alumina increasing the isomerization reaction.

The main objective of this article is to determine the real salaries and living conditions of construction workers in Santiago de Chile towards the end of the colonial period (c. 1788–1808). To achieve this purpose, we have used the methodology proposed by Allen to calculate real salaries in terms of welfare ratios. Our main conclusions are: the real salaries of non-qualified workers remained above the subsistence levels throughout the entire period studied in this work, pointing to a lack of labour force in Santiago for this period (in spite of a population increase during the same period); there was also a significant proportion of qualified workers in the construction sector who earned 2–3 times more than non-qualified workers, giving rise to a notable heterogeneity in the mean income of workers in this sector and a greater difference than in other cities; despite being above the subsistence levels, the real salaries of non-qualified workers in Santiago appear to be among the lowest in the region, in contrast with previous conclusions in this respect.

Glycerol dehydration to acrolein was studied with three catalysts using zeolite-Y. This zeolite in its protonic form (HY), with La (LaY) and Pd with La (Pd/LaY), was characterized by X-ray diffraction (XRD), Fourier-transform-infrared spectroscopy (FTIR) with pyridine, BET, Scanning Electron Microscope (SEM)–Energy-Dispersive Spectroscopy X-ray (EDS) and the catalytic activity tests were carried out under H2 atmosphere. It was found that La ions exchanged in the zeolite-Y resulted in the improvement of both glycerol conversion and yield to acrolein, also a relatively constant glycerol conversion was achieved up to three hours, due to the presence of Pd on the catalyst and H2 in the feed. The comparison of the calculated and experimental yields obtained from the catalytic tests of the Pd/LaY catalyst indicates a greater activity for the reaction to acrolein than for the reaction to acetol. The calculated equilibrium yields of the dehydration reaction from glycerol to acrolein, acetol, ethanal, methanol, and water and the experimental yields of a Pd/LaY catalyst were compared. Thermodynamically, a complete conversion of glycerol can be achieved since the general system remains exothermic and promotes the path to acetol below 480 K. Above this temperature the system consumes energy and favors the production of acrolein, reaching its maximum concentration at 600 K.

In the hydroprocessing of coker naphtha (hydrodesulfuration and hydrodenitrogenation), silica poisoning of hydrotreating catalysts represents a severe problem due to the deposition of Si species, which deactivate the catalyst and shorten its life time. The deactivation results of the sulfided NiMo/γ-Al 2 O 3 hydrotreating catalyst, obtained by running a long-term test, are presented. Refinery coker naphtha was processed in a continuous hydroprocessing unit in a mini-scale laboratory under industrial conditions. Catalyst samples from 15 to 90 days on stream were characterized. Si determination and the evolution of the structural characteristics of these samples were followed by 29 Si MAS NMR, FTIR, textural analysis and scanning electron microscopy (SEM) performing microanalysis by dispersion energies (EDS). 29 Si MAS NMR results confirmed the deposition and evolution of different Si species on the catalyst surface with the time on stream. The increasing content of Si species in the catalyst affected textural properties such as surface area and pore volume by decreasing them; as for the chemical properties, the Bronsted/Lewis (B/L) ratio was modified without increasing the coke formation and cracking activity. From the coker naphtha hydrotreating processes, only the hydrodenitrogenation activity was affected. The Si deposition profile shows that the concentrations were higher in the external than in the internal surface of the pellets. The shape of these profiles indicates that the deposition process becomes diffusion rate limited.

γ-Alumina-based HDT catalysts used as silicon traps adsorb more efficiently silicon compounds from naphtha till saturation, which occurs at a relatively low concentration (5–10 wt%). As the silicon content in the catalyst increases, the surface is progressively deactivated, mainly affecting the hydrodenitrogenation and hydrogenation activity. According to the aforementioned, the deactivation of HDT catalysts was investigated by means of a fraction of naphtha doped with silicone oil with different concentrations, which was used to contaminate the catalysts. The presence of silicon species was detected by 29Si NMR and FTIR spectroscopies. The Si O Al formation was evidenced by the B/L ratio measured for the doped HDT catalysts. The results obtained for the deactivation of HDT catalysts exposed to high silicon contents show that this factor plays a major role in the loss of activity.

In the present work, two supported liquid membranes, which used two new ionic liquids (ILs) as mobile phase, 1-(2-aminoethyl)-3-methylimidazolium trifluoromethanesulfonate ([AEMIm]Tf) and trioctylmethylammonium anthranilate ([TOMA])An, were studied characterizing their chemical structures by NMR and FTIR. Both the impregnation level and mass of the ILs in alumina tubular supports were determined by SEM-EDX mapping and gravimetric analysis. The permeation tests were carried out using pure gases at 25 °C and 1 bar. It was confirmed that in the ILs, [AEMIm]Tf and [TOMA]An, the amine groups reacted with CO2, leading to the formation of carbamates. The IL [TOMA]An, which has the amine group at the anionic part, showed the best ideal permselectivity, reaching a selectivity of 92.

Pt supported on tungstated zirconia catalysts (Pt/WZ) doped with different Fe contents were evaluated in the n-hexane hydroisomerization reaction. High-throughput experimentation (HTE) approaches were used to investigate the effect of the iron incorporation over the catalytic activity. It was found that the presence of iron at low concentrations (0.5–1 wt%) increases the conversion and the yield to the high octane 2,2-dimethyl-butane (2,2-DMB) isomer. The characterization results suggest that the presence of iron modifies the nanostructure of the WOx species on the zirconia surface which in turn produces the generation of active Bronsted acid sites thus optimizing the tungsten content toward the highest catalytic activity. It was also found that the surfactant incorporation further improves the performance of Pt/WZ catalysts, although, the activity was improved with the Fe addition at lower concentration.

In this study we report the formation of nanocrystals and nanotubes of TiO2 synthesized by the sol–gel method and hydrothermal treatment respectively. The obtained TiO2 nanostructures were characterized by XRD, BET, TEM, UV–vis, XPS and FTIR; and evaluated in the CO oxidation. As for the nanotube-based samples, two catalysts were prepared (NTB5 and NTB10) through the hydrothermal treatment of nanosized titania in NaOH (5 and 10 N) at 160 °C, followed by HCl rinsing until pH 1 was reached. From both catalysts, NTB10 showed the highest surface area (290 m2/g), nanocrystals (15 nm) and stable phase (H2Ti3O7) with a high CO oxidation capacity. We found that the band gap for NTB10 catalyst was of 2.85 eV, the lowest value respect to that of NTB5 and SGTB3 catalyst, based material (SGTB) showed both the lowest textural properties and catalytic performance.

Methane catalytic decomposition (MCD) over Ni/MCM-41 catalysts was tested in a microreactor to simultaneously produce hydrogen and carbon nanotubes (CNTs). The methane conversion reached 30% to 47% at a moderate temperature range from 400°C to 600°C and the catalytic activity of the catalysts remains stable during 500 min steam on time. CNTs were chiefly formed through tip-growth mode, due to the weak interaction between the metallic Ni and the support. Most of the Ni particles are located on the tip of the produced CNTs, which avoids rapid deactivation of the catalyst resulted from carbon encapsulation. Large Ni particles usually lead to the formation of CNTs with big diameter. During the reaction, the shape of Ni particles changed from pseudo-sphere to diamond-like. All the CNTs consist of multiple layer walls and are curved in certain degree.

A zirconium modified MCM-48 mesoporous material was synthesized by surfactant-templated method. Surface grafting Zr-MCM-48 with tungstophosphoric acid led to a great enhancement of both the number of the Br?nsted acid sites and acidity strength in comparison with the bare support. At 100°C, the 30 wt% H3PW12O40/Zr-MCM-48 contained 174 μmol/g Br?nsted acid sites which were 14.5 times greater than that of Zr-MCM-48. The Keggin structure of the grafted heteropolyacid was rather stable after calcination at 400°C for 2 h, approximately 93.3% of Keggin structure in the dispersed heteropolyacid were remained without destruction but slightly distorted in some degree, as evidenced by FTIR characterization and 31P NMR-MAS analysis. This H3PW12O40/Zr-MCM-48 solid with three dimensional mesoporous system, large surface area and very strong Br?nsted acidity will be a promising catalyst for acid catalytic reactions.

A comparison was made of the effectiveness of the functionalization reactions of pentacyclo[5.4.0.02,6.03,10.05,9]undecane-8,11-dione (PCU) using sulphated zirconia in protection-deprotection reactions and Mg/Al hydrotalcite in a cyanosilylation reaction, under classical thermal conditions and imposing microwave radiation; improved yields and reaction times were considered.

The Rh and Rh–Sn supported catalyst on γ-Al2O3 and γ-Al2O3–CeO2 (loading 1, 5 and 20 Ce wt%) were characterized by means of electron microscopy (TEM), temperature programmed reduction (TPR), Fourier transformed infrared of CO adsorption (FTIR-CO) and X-ray photoelectron spectroscopy (XPS). The catalysts were tested in the catalytic wet air oxidation of an aqueous solution of 227 ppm of TAME and 1 g/L of catalyst (120 °C and 10 bar of oxygen partial pressure). The rhodium monometallic catalysts showed an increase in the activity with the load of cerium oxide in the catalyst. The coexistence of Rh°/Rhδ+ and Ce4+/Ce3+ redox couples facilitates the activation of TAME and hence the catalytic activity and selectivity to mineralization. The addition of Snδ+ enhances the activity and selectivity; this is explained by assuming that Snδ+ acts as Lewis acid sites trapping the TAME molecules for further oxidation on rhodium metal particles.

Anatase with nanotubular (NT) and nanofibrilar (NF) morphology was obtained by annealing treatment at 773 and 873 K of a hydrous titanate with nanotubular morphology synthesized by alkali hydrothermal method. The surface properties were compared with those of a commercial anatase made up of nanoparticles (NPs); materials with similar specific surface area were selected for this end. Low temperature CO adsorption FTIR showed only one adsorption site on the OH groups of nanotubes and nanofibers and almost no Lewis sites were detected suggesting the absence of coordinatively unsaturated Ti4+ sites in NT and NF samples. All the OH groups on anatase nanotubes are exposed on the surface, and they are not of Bronsted type. The OH groups in NT and NF adsorb 2.2 times pyridine or lutidine molecules than nanoparticles via H-bonding interaction. These weak interactions are very attractive in the elimination of N-compounds from oil fractions using regenerable adsorbents.

The effect of the Bronsted/Lewis acid ratio on isomerization of n-heptane using Al 2 O 3 as a source of Lewis acidity and WOx/ZrO 2 as a source of Bronsted and Lewis acidity was studied and controlled using mechanical mixtures of these solids. These mixtures were characterized by surface area, infrared spectroscopy of pyridine, X-ray diffraction and Raman spectroscopy. It was found that the presence of W O stretching mode which was consistent with the presence of oxotungstate species which were the precursors of the acid sites. It was found out that as the oxotungstate structures increased, the selectivity to n-heptane isomers increased while the hydrocracking and dehydrocyclization selectivity decreased. The presence of Bronsted acidity of the WOx/ZrO 2 domains, the increase of Knudsen diffusivity and the loss of Pt metallic area by strong interaction of the Pt with the WOx/ZrO 2 explain this catalytic behavior.

The liquid phase alkylation of benzene with dec-1-ene was catalyzed by 12-tungstophosphoric acid (WP) supported on different solids (ZrO2, SiO2, activated carbon and boehmite-Al2O3). Catalysts prepared with 20 wt.% of WP were thermally treated at 300 °C and then the acidity was estimated by FT-IR pyridine adsorption spectroscopy. Additionally, the catalysts were characterized by X-ray diffraction, thermal gravimetric analysis, and N2 adsorption measurements. Thermal stability of supported WP and changes in textural properties of the catalysts were analyzed. Of all the catalysts, 20WP on SiO2 showed the highest acidity and was found to be the most active catalyst in alkylation of benzene with dec-1-ene at 80 °C, at dec-1-ene conversion of 70% and alkyl benzenes selectivity of nearly 40%.

The study presented here compares the performance of different zeolite catalysts (Beta, ZSM-5 and Beta:ZSM-5 composites) for benzene alkylation by propylene with a benzene enriched reformate heart-cut (13 wt% benzene). The experiments were carried out in a batch system with a 1/1 benzene:propylene mole ratio at 220 °C for 1 h. The results showed that an increase in conversion produced decreases in cumene selectivity and oligomers formation. These results were associated to Beta contained catalysts. Lower conversions related to a higher oligomers production and lower di-isorpropylbenzene isomers formation, were obtained with a ZSM-5 catalyst. Results were compared with pure benzene/propylene alkylation tests carried out at similar experimental conditions.