Perceptions about Entrepreneurship in the COVID-19 Era

Este trabajo tuvo como objetivo determinar un modelo para el estudio del sector cafetero a través de una investigación transversal y exploratoria con una selección no aleatoria de 100 comerciantes de café y sus derivados. A partir de un modelo estructural, se identificaron las percepciones en torno a cinco dimensiones de oportunidad: económica, financiera, comercial, social y ambiental. Con base en los marcos teóricos y conceptuales abordados, proponemos estudiar las percepciones en torno al emprendimiento por parte de grupos vulnerables dedicados a la comercialización de subproductos del café como medio de subsistencia. Los hallazgos permiten establecer un vínculo entre la teoría de la elección racional y la teoría del capital humano frente a la teoría de los comunes y la teoría del emprendimiento social, los cuales surgen como marcos conceptuales pertinentes para la intervención financiera de este tipo de emprendedores.This work sought to specify a model for the study of the coffee-growing sector. A cross-sectional and exploratory research with a non-random selection of 100 coffee traders was carried out. From a structural model reliability and validity, five dimensional perceptions of economic, financial, sales, social, and environmental opportunity were identified. Based on the theoretical and conceptual frameworks, we propose to study the entrepreneurial perceptions of vulnerable groups dedicated to the trading of coffee byproducts as a subsistence means. The findings allow us to establish a link between rational choice theory and the theory of human capital with respect to the theory of the commons and the theory of social entrepreneurship as conceptual frameworks to highlight the intervention in microfinance made with entrepreneurs

Catalytic asymmetric transfer hydrogenation of ketones: recent advances

In this review, we consider the main processes for the asymmetric transfer hydrogenation of ketones from 2008 up today. The most effective organometallic compounds (derived from Ru, Rh, Ir, Fe, Os, Ni, Co, and Re) and chiral ligands (derived from amino alcohols, diamines, sulfur- and phosphorus-containing compounds, as well as heterocyclic systems) will be shown paying special attention to functionalized substrates, tandem reactions, processes under non-conventional conditions, supported catalysts, dynamic kinetic resolutions, the use of water as a green solvent, theoretical and experimental studies on reaction mechanisms, enzymatic processes, and finally applications to the total synthesis of biologically active organic molecules.We thank the continuous financial support from our Ministerio de Ciencia e Innovación (MICINN) (projects CTQ2007-62771/BQU, CTQ2010-20387, CONSOLIDER INGENIO 2010-CDS2007-00006, CTQ2011-24151, CTQ2011-24165), the Ministerio de Economía y Competitividad (MINECO) (projects CTQ2013-43446-P, CTQ2014-51912-REDC, CTQ2014-53695-P), FEDER, the Generalitat Valenciana (PROMETEO 2009/039, PROMETEOII/2014/017), and the University of Alicante

Microwave-Promoted Copper-Free Sonogashira–Hagihara Couplings of Aryl Imidazolylsulfonates in Water

Aryl imidazol-1-ylsulfonates have been efficiently cross-coupled with aryl-, alkyl-, and silylacetylenes in neat water under copper-free conditions at 110 °C assisted by microwave irradiation. Using 0.5 mol% of an oxime palladacycle as precatalyst, 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl (SPhos, 2 mol%) as ligand, hexadecyltrimethylammonium bromide (CTAB) as additive, and triethylamine (TEA) as base, a wide array of disubstituted alkynes has been prepared in good to high yields in only 30 min.Financial support from the MICINN (Projects CTQ2007-62771/BQU, CTQ2010-20387 and Consolider INGENIO 2010 CSD2007-00006), FEDER, from the Generalitat Valenciana (Project PROMETEO/2009/038), and the University of Alicante is acknowledged

Metal-Catalyzed Enantioconvergent Transformations

Enantioconvergent catalysis has expanded asymmetric synthesis to new methodologies able to convert racemic compounds into a single enantiomer. This review covers recent advances in transition-metal-catalyzed transformations, such as radical-based cross-coupling of racemic alkyl electrophiles with nucleophiles or racemic alkylmetals with electrophiles and reductive cross-coupling of two electrophiles mainly under Ni/bis(oxazoline) catalysis. C–H functionalization of racemic electrophiles or nucleophiles can be performed in an enantioconvergent manner. Hydroalkylation of alkenes, allenes, and acetylenes is an alternative to cross-coupling reactions. Hydrogen autotransfer has been applied to amination of racemic alcohols and C–C bond forming reactions (Guerbet reaction). Other metal-catalyzed reactions involve addition of racemic allylic systems to carbonyl compounds, propargylation of alcohols and phenols, amination of racemic 3-bromooxindoles, allenylation of carbonyl compounds with racemic allenolates or propargyl bromides, and hydroxylation of racemic 1,3-dicarbonyl compounds.We gratefully acknowledge financial support from the Spanish Ministerio de Ciencia, Innovación y Universidades (projects CTQ2016-81893REDT and RED2018-102387-T); the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI), and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P, CTQ2016-80375-P, CTQ2017-82935-P, and PID2019-107268GB-I00); Generalitat Valenciana (CIDEGENT/2020/058); and the University of Alicante

Stereodivergent routes in organic synthesis: marine natural products, lactones, other natural products, heterocycles and unnatural compounds

Enantio- and diastereodivergent routes to marine-origin natural products with different sizes of cyclic ethers and lactones have been used in order to assign stereochemical features. Kainoid amino acids such as isodomoic acids have been synthesized using diastereodivergent routes. The bis(indole) alkaloid dragmacidin F has been prepared by enantiodivergent strategies as well as furanoterpenes and the tetracyclic agelastatin A. Natural products containing five-membered lactones like quercus lactones, muricatacins, goniofufuranones, methylenolactocins and frenolicin B have been synthesized using stereodivergent routes. Macrolides are very abundant lactones and have been mainly prepared from the corresponding seco-acids by lactonization, such as lasiodiplodin, zaeralanes, macrosphelides and haloprins, or by ring-closing metathesis, such as aspercyclides, microcarpalides, macrolides FD-891 and 892, and tetradic-5-en-9-olides. Other natural products including cyclic ethers (such as sesamin, asarinin, acetogenins, centrolobines and nabilones), alcohols (such as sulcatol), esters (such as methyl jasmonates), polycyclic precursors of fredericamycin, amino alcohols (such as ambroxol and sphingosines), isoprostanes, isofurans, polyketide precursors of anachelins, brevicomins, gummiferol, shikimic acid and the related compounds, and the pheromone disparlure have been synthesized stereodivergently. Heterocyclic systems such as epoxides, theobroxides and bromoxones, oxetan-3-ones, 5- to 8-membered cyclic ethers, azetidones, γ-lactams, oxazolidinones, bis(oxazolines), dihydropyridoisoindolines and octahydroisoquinolines have been prepared following stereodivergent routes. Stereodivergent routes to unnatural compounds such as alkenes, dienes, allenes, cyclopropanes, alcohols, aldols, amines, amino alcohols, β-amino acids, carboxylic acids, lactones, nitriles and α-amino nitriles have been considered as well.We thank the Spanish Ministerio de Economía, Industria y Competitividad, Gobierno de España, Agencia Estatal de Investigación (AEI) and European Regional Development Fund (FEDER, EU) (projects CTQ2016-76782-P, CTQ2016-81797-REDC, and CTQ2017-85093-P), the Generalitat Valenciana (PROMETEOII/2014/017) and the Universidad de Alicante for financial support

Stereodivergent routes in organic synthesis: carbohydrates, amino acids, alkaloids and terpenes

The natural occurrence of enantiomers and diastereomers is often encountered. In addition, the synthesis of these stereoisomers is important for structure determination and for the study of structure–activity relationships. Stereodivergent routes simplify the access to these molecules starting from a common material. This review is focused on the synthesis of carbohydrates, amino acids, alkaloids and terpenes using this efficient strategy. In the case of carbohydrates, such as monosaccharides, carbasugars, aminosugars and azasugars, carbohydrates are usually employed as common starting materials. As a very common strategy, configurations of hydroxy groups are inverted by SN2 methods playing with protection and deprotection processes. For the synthesis of acyclic α-AAs, diastereoselective methods using mainly Garner's aldehyde have been described. Diastereodivergent routes allowed the synthesis of β-hydroxy- and β-amino-α-amino acids, as well as of β- and γ-amino acids. Heterocyclic and cyclic amino phosphonic acids were synthesized using diastereodivergent routes. Alkaloids containing five- and six-membered saturated azaheterocycles needed multistep stereodivergent routes and other alkaloids, such as enantiomers of balanol, vincamine, anatoxin and codeine, and diastereomeric isochaetominines C and galanthamines. In the terpene field, sesquiterpenes β-santalene, α-curcumene and α-cuparenone and the diterpene scopadulcic acid A have been synthesized using enantiodivergent routes.We thank the Spanish Ministerio de Economía, Industria y Competitividad, Agencia Estatal de Investigación (AEI) and Fondo Europeo de Desarrollo Regional (FEDER, EU) (projects CTQ2016-76782-P, CTQ2016-81797-REDC, and CTQ2017-85093-P), the Generalitat Valenciana (PROMETEOII/2014/017) and the University of Alicante for financial support

Novel probes for simultaneous dual-colour labelling of mitochondria and lysosomes.

Cellular activity depends on the accurately controlled and synchronised functions of the subcellular organelle ensemble. In this context, lysosomes and mitochondria are central to cellular metabolism as major contributors of chemical energy and building blocks. The coordination of lysosomal and mitochondrial metabolic roles is thus essential for cellular homeostasis, with dysfunction of these organelles associated with many human diseases. Confocal and two-photon (2P) microscopy are state-of-the-art techniques for live imaging due to their operational simplicity, excellent spatial and temporal resolution and non-invasiveness. Consequently, fluorescent dyes that specifically label subcellular structures have become vital tools for cell biology and biomedical science, and multiple dyes labelling different structures can be combined to follow complex cellular processes. However, using different labels adds cost and complexity to experiments. Thus, for biomedical research applications, a single fluorescent molecule for labelling multiple subcellular structures with organelle-specific photophysical properties has numerous advantages, including lowering cost and experimental complexity while improving the quantification of phenotypes. Based in our previously described ROS-sensor and cellular pH probe, in this communication we describe novel indolium fluorophores for labelling mitochondria and lysosomes with organelle-specific fluorescence properties, which can be readily distinguished by combining confocal and two-photon fluorescence microscopy. Our results show that this unique behaviour relies on aggregation. These probes allow for unambiguous and simultaneous visualisation of mitochondria and lysosomes in separate emission channels by using a single fluorescent marker within living cells.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Elaboración del Plan Municipal de Gestión de Residuos Sólidos del Cantón Mocha, Provincia de Tugurahua

Esta investigación se realizó sobre el Plan de Gestión de Residuos Sólidos del Cantón Mocha, Provincia de Tungurahua. Basándose en experiencias previas y mejora continua del medio ambiente se estudio las consecuencias de los efectos ambientales que los residuos sólidos puedan causar sobre la calidad de vida del Cantón. Con las entrevistas realizadas a los funcionarios de la Municipalidad y la población en general se recopiló datos que permitieron al Municipio desarrollar un proyecto que garantice la sostenibilidad ambiental de los patrones de desarrollo socio económicos, a través de la búsqueda de la eficiencia, mejoramiento de la calidad y cobertura de los servicios de recolección de basura, agua potable y alcantarillado. También se estudio de forma técnica sobre los desechos en la zona y sobre la participación de la población para lograr una mejor educación sobre el manejo de los residuos. Como resultado de ésta investigación se elaboró un Plan de Gestión de Residuos Sólidos el mismo que contribuirá con el diseño y ejecución de estrategias que permitirán identificar formas para el manejo adecuado de los factores críticos de cada realidad. Además se podrá identificar las oportunidades de un manejo ambiental adecuado para la prevención y mitigación de los impactos socio ambientales negativos. Como conclusión de éste proyecto se señala que no existe una normativa legal, que permita el manejo adecuado de los desechos de forma técnica. Se recomienda a la Municipalidad del Cantón Mocha la formulación de ordenanzas que permitan regular el Manejo de Residuos Sólidos del Cantón y la generación de fuentes de trabajo con la producción de abono orgánico.This research was done related to a Waste Management Plan Solid in the Mocha Canton, Tungurahua Province. Based on previous experience and continuous improvement of the environment, the environmental effect of solid waste on the quality of life in Canton was studied. With interviews with officials of the Municipality and the general population data was collected. This data was used by the municipality to develop a project that contributes to ensure the environmental sustainability of socio-economic development patterns, through the pursuit of efficiency , improving the quality and coverage of services garbage collection, water and wastewater. Also a technical study on disposal of waste and the participation of the people to be better educated on the handling waste were conducted. As a result of this investigation the Plan Solid Waste Management was elaborated which contribute to the design and implementation of strategies to identify ways for the proper management of the critical factors of each situation, and the opportunities of environmental management for the prevention and mitigation of negative social and environmental impacts. As conclusion of this project it was detected the lack of legal regulation, to allow proper handling of waste, in a technical manner. It is recommended that the City of Canton Mocha can create ordinances to regulate Solid Waste Management in its canton and the generation of jobs for the organic fertilizer production

Aproximación al estudio de procedencia y tecnología de fabricación de las cerámicas campaniformes del yacimiento de la edad del cobre de los millares

En este trabajo se lleva a cabo el estudio analítico mediante Espectrometría de Masas, Difracción de Rayos-X y Microscopio Estereoscópico de un conjunto de vasijas cerámicas de estilo campaniforme procedentes del yacimiento de la Edad del Cobre de Los Millares. El análisis químico se ha centrado en el estudio de los elementos denominados tierras raras que constituyen un indicador exce lente del origen de los materiales. El estudio mineralógico así como la observa ción óptica han aportado información sobre procesos tecnológicos de manufacturación