A Mathematical Model to Evaluate the Kinetics of D-glucose and D-fructose Fermentations by Saccharomyces bayanus at Increasing Ethanol Concentrations

In the cellar, slow and stuck fermentations occurring during winemaking are often successfully solved bythe addition of yeast strains like Saccharomyces bayanus. The kinetic behaviour shown by S. bayanus duringalcoholic fermentation was investigated using a mathematical model previously tested for S. cerevisiae, inorder to show which of the six functional parameters of the model differed significantly with the yeastpopulation. Although some parameters (hexose fractions converted to ethanol and glycerol) did not change,the kinetic constant related to the inactivation rate of the yeast population showed by S. cerevisiae assumeda value significantly higher (approximately 50-fold) than that observed for S. bayanus, while this latterpopulation was ten times less affected by ethanol than S. cerevisiae. Although no remarkable differencescould be found between the ability shown by the two yeast populations to convert hexoses (D-glucose andD-fructose), the tolerance for ethanol accumulation changed strongly. The conversion rate of these twohexoses by S. bayanus was affected less (about ten thousand-fold) by ethanol than that of S. cerevisiae

Power density of a bare electrodynamic tether generator

The maximum performance of bare electrodynamic tethers as power generating systems under OML-theory is analyzed. Results show that best performance in terms of power density is achieved by designing the tether in such a way to increase ohmic impedance with respect to plasma contact impedance, hence favoring longer and thinner tethers. In such condition the corresponding optimal value of the load impedance is seen to approach the ohmic impedance of the conducting tether. At the other extreme, when plasma contact impedance dominates (which is not optimal but can be relevant for some applications) optimum power generation is found by matching the load impedance with an effective tether-plasma contact impedance whose expression is derived

Metal-based compounds containing selenium: An appealing approach towards novel therapeutic drugs with anticancer and antimicrobial effects

In recent years, both metal-based complexes and selenium-containing compounds have been widely explored for their therapeutic properties due to their roles in biological processes and modulation of diverse molecular tar- gets. However, despite their growing interest, there is no review to date that covers the potential use of the combination of these entities to design new therapeutic derivatives. This review highlights the latest achieve- ments in this particular field, with a focus on compounds with anticancer and/or antimicrobial properties. With this aim, the formation of coordination compounds including several metals bearing selenium either with direct interaction with the metal center or as part of the organic ligand elsewhere is covered. Besides, coordination compounds with a Se(IV) center have been assessed. The biological properties of several selenium-containing organometallic complexes have also been discussed, including metallocenes, half-sandwich complexes, and compounds with N-heterocyclic carbenes, CO, and π-ligands, and other σ-bonded entities. The information compiled in this review may be helpful to design and develop novel, more potent, and safer metal-based com- pounds for the treatment of several pathologies

Balance social de las microempresas de la confección, herrería y carpintería de las comunas 14 y 15 de la zona Suroccidental de Cartagena de Indias: un modelo administrativo enfocado al desarrollo socio económico de la comunidad

Las vivencias de la época actual en el campo económico y empresarial presentan una clara tendencia hacia la libre iniciativa privada, impulsada por la diversificación y evolución de nuestras estructuras a través de una descentralización económica que delega en las diferentes organizaciones una serie de responsabilidades tanto económicas como sociales. Surge de ésta tendencia la concepción de la empresa como un ente socioeconómico, que por la misma naturaleza de su conformación y funcionamiento a través de un conjunto de seres humanos en interacción constante en el ámbito interno y con entidades externas, da lugar a la reafirmación de la importancia del rol que debe desempeñar la empresa como facilitador no sólo de la ejecución de una función económica sino también de funciones socialesIncluye bibliografíaMagíter Administración de Empresa

Small molecules containing chalcogen elements (S, Se, Te) as new warhead to fight neglected tropical diseases

Neglected tropical diseases (NTDs) encompass a group of infectious diseases with a protozoan etiology, high incidence, and prevalence in developing countries. As a result, economic factors constitute one of the main obstacles to their management. Endemic countries have high levels of poverty, deprivation and marginalization which affect patients and limit their access to proper medical care. As a matter of fact, statistics remain un- collected in some affected areas due to non-reporting cases. World Health Organization and other organizations proposed a plan for the eradication and control of the vector, although many of these plans were halted by the COVID-19 pandemic. Despite of the available drugs to treat these pathologies, it exists a lack of effectiveness against several parasite strains. Treatment protocols for diseases such as American trypanosomiasis (Chagas disease), leishmaniasis, and human African trypanosomiasis (HAT) have not achieved the desired results. Un- fortunately, these drugs present limitations such as side effects, toxicity, teratogenicity, renal, and hepatic impairment, as well as high costs that have hindered the control and eradication of these diseases. This review focuses on the analysis of a collection of scientific shreds of evidence with the aim of identifying novel chalcogen- derived molecules with biological activity against Chagas disease, leishmaniasis and HAT. Compounds illustrated in each figure share the distinction of containing at least one chalcogen element. Sulfur (S), selenium (Se), and tellurium (Te) have been grouped and analyzed in accordance with their design strategy, chemical synthesis process and biological activity. After an exhaustive revision of the related literature on S, Se, and Te compounds, 183 compounds presenting excellent biological performance were gathered against the different causative agents of CD, leishmaniasis and HAT

A pan-Canadian dataset of neighbourhood retail food environment measures using Statistics Canada's Business Register.

BACKGROUND: The objective of this study was to create the Canadian Food Environment Dataset (Can-FED) and to demonstrate its validity. DATA AND METHODS: Food outlet data were extracted from Statistics Canada's Business Register (BR) in 2018. Retail food environment access measures (both absolute and relative measures) were calculated using network buffers around the centroid of 56,589 dissemination areas in Canada. A k-medians clustering approach was used to create categorical food environment variables that were easy to use and amenable to dissemination. Validity of the measures was assessed by comparing the food environment measures from Can-FED with measures created using Enhanced Points of Interest data by DMTI Spatial Inc. and data from a municipal health inspection list. Validity was also assessed by calculating the geographic variability in food environments across census metropolitan areas (CMAs) and assessing associations between CMA-level food environments and CMA-level health indicators. RESULTS: Two versions of Can-FED were created: a researcher file that must be accessed within a secure Statistics Canada environment and a general-use file available online. Agreement between Can-FED food environment measures and those derived from a proprietary dataset and a municipal health inspection list ranged from rs=0.28 for convenience store density and rs=0.53 for restaurant density. At the CMA level, there is wide geographic variation in the food environment with evidence of patterning by health indicators. INTERPRETATION: Can-FED is a valid and accessible dataset of pan-Canadian food environment measures that was created from the BR, a data source that has not been explored fully for health research

The residues of fruit and vegetable pro-cessing: From “waste” to “resource” of natural phytochemical compounds

The project of Sant’Anna School, in line with the Italian legislation on limiting waste and promoting the redistribution of surpluses and unused goods, aimed to study the potential healthy value of residues obtained from the trans-formation of fruit and vegetable products that represent a cost, as they must be handled, stored and disposed according to stringent actual regulations. Two “model” species (potato and apple) were considered to test the possibility of using industrial processing waste for food applications. The extracts, obtained with “green” methods from potato and apple peels, were evaluated as natural antioxidants in the preparation of minimally processed fresh­cut apple. Results suggest the possibility to use these novel byproduct extracts as valuable alter-native treatments to traditional chemical additives employed for minimally processed apples

Novel methylselenoesters induce programed cell death via entosis in pancreatic cancer cells

Redox active selenium (Se) compounds have gained substantial attention in the last decade as potential cancer therapeutic agents. Several Se compounds have shown high selectivity and sensitivity against malignant cells. The cytotoxic effects are exerted by their biologically active metabolites, with methylselenol (CH3SeH) being one of the key executors. In search of novel CH3SeH precursors, we previously synthesized a series of methylselenoesters that were active (GI50 < 10 µM at 72 h) against a panel of cancer cell lines. Herein, we refined the mechanism of action of the two lead compounds with the additional synthesis of new analogs (ethyl, pentyl, and benzyl derivatives). A novel mechanism for the programmed cell death mechanism for Se-compounds was identified. Both methylseleninic acid and the novel CH3SeH precursors induced entosis by cell detachment through downregulation of cell division control protein 42 homolog (CDC42) and its downstream effector β1-integrin (CD29). To our knowledge, this is the first time that Se compounds have been reported to induce this type of cell death and is of importance in the characterization of the anticancerogenic properties of these compounds