First Exclusive Stereo- and Regioselective Preparation of 5-Arylimino-1,3,4-Selenadiazole Derivatives: Synthesis, NMR analysis, and Computational Studies.

Isoselenocyanates are valuable coupling partners required for preparing key chemical intermediates and biologically active molecules in an accelerated and effective way. Likewise, (Z)-2-oxo-N-phenylpropanehydrazonoyl chlorides have been employed in numerous one-step heteroannulation reactions to assemble the structural core of several various kinds of heterocyclic compounds. Here, we describe the inverse electron demand 1,3-dipolar cycloaddition reaction of isoselenocyanates with a variety of substituted (Z)-2-oxo-N-phenylpropanehydrazonoyl chlorides to generate, regioselectively and stereoselectively, a series of 5-arylimino-1,3,4-selenadiazole derivatives comprising a multitude of functional groups on both aryl rings. The synthetic method features gentle room-temperature conditions, wide substrate scope, and good to high reaction yields. The selenadiazoles were separated by gravity filtration in all instances and chemical structures were validated by multinuclear NMR spectroscopy and high accuracy mass spectral measurements. First conclusive molecular structure elucidation of the observed 5-arylimino-selenadiazole regioisomer was verified by single-crystal X-ray diffraction analysis. Crystal-structure measurement was successfully carried out on (Z)-1-(4-(4-iodophenyl)-5-(p-tolylimino)-4,5-dihydro-1,3,4-selenadiazol-2-yl)ethan-1-one and (Z)-1-(5-((4-methoxyphenyl)imino)-4-(4-(methylthio)phenyl)-4,5-dihydro-1,3,4-selenadiazol-2-yl)ethan-1-one. Likewise, the (Z)-geometry of the hydrazonoyl chloride reactant was proven by X-ray diffraction studies. As representative examples, crystal-structure determination was carried out on (Z)-2-oxo-N-phenylpropanehydrazonoyl chloride and (Z)-N-(3,5-bis(trifluoromethyl)phenyl)-2-oxopropanehydrazonoyl chloride. Density functional theory calculations at the B3LYP-D4/def2-TZVP level were conducted to support the noted experimental findings and suggested mechanism.

Simultaneous biosuccinic production and biogas upgrading: Exploring the potential of sugar-based confectionery waste within a biorefinery concept.

The imminent need for fossil fuel independence in EU countries has led to an increased development of organic waste valorisation technologies for the production of biomethane and chemical building blocks, such as bio-succinic acid (SA). In this work, the potential of two confectionery waste, in the form of wastewater (SCWW) or a side-stream rejection (SSCW), as inexpensive carbon sources for simultaneous SA production and biogas upgrading was evaluated for the first time. Both substrates were tested batchwise with evolved Actinobacillus succinogenes cultures at different nutrient conditions, SSCW at 100 g L-1 resulting in the highest titres/productivities (∼80 g L-1 and 1.3 g L-1h-1, respectively). Then, simultaneous biogas upgrading under continuous gas feeding was studied at bioreactor-scale, higher gas residence times and pressurization leading to desirable biomethane purities (>98%). The research here conducted is crucial for the cost-effectiveness and scale-up of the technology along this new waste-based biorefinery concept.

Room-Temperature C-C σ-Bond Activation of Biphenylene Derivatives on Cu(111).

Activating the strong C-C σ-bond is a central problem in organic synthesis. Directly generating activated C centers by metalation of structures containing strained four-membered rings is one maneuver often employed in multistep syntheses. This usually requires high temperatures and/or precious transition metals. In this paper, we report an unprecedented C-C σ-bond activation at room temperature on Cu(111). By using bond-resolving scanning probe microscopy, we show the breaking of one of the C-C σ-bonds of a biphenylene derivative, followed by insertion of Cu from the substrate. Chemical characterization of the generated species was complemented by X-ray photoemission spectroscopy, and their reactivity was explained by density functional theory calculations. To gain further insight into this unique reactivity on other coinage metals, the reaction pathway on Ag(111) was also investigated and the results were compared with those on Cu(111). This study offers new synthetic routes that may be employed in the in situ generation of activated species for the on-surface synthesis of novel C-based nanostructures.

New efficient meta-fermentation process for lactic acid production from municipal solid waste.

BACKGROUND: The global market for lactic acid is witnessing growth on the back of increasing applications of lactic acid for manufacturing polylactic acid. Indeed, the lactic acid market is expected to reach 9.8 billion US dollars by 2025. The new concept of meta-fermentation has been proposed in recent years as an alternative to fermentation with pure cultures, due to multiple advantages such as lower susceptibility to contamination, no need for sterilization of culture media or lower raw material costs. However, there are still challenges to overcome to increase the conversion efficiency, decrease formation of by-products and facilitate fermentation control. In this context, the purpose of the study was to develop a robust meta-fermentation process to efficiently produce lactic acid from the OFMSW, stable at pre-industrial scale (1500 L). To maximize lactic acid production, operating conditions (pH, HRT) were modified, and a novel bioaugmentation strategy was tested. RESULTS: A LAB-rich inoculum was generated with LAB isolated from the digestate and grown in the laboratory with MRS medium. After feeding this inoculum to the digester (bioaugmentation), lactic acid accumulation up to 41.5 gO2/L was achieved under optimal operating conditions. This corresponds to more than 70% of the filtered COD measured in the digestate. The amount of lactic acid produced was higher than the volatile fatty acids under all feeding strategies applied. CONCLUSIONS: The operating conditions that enhanced the production of lactic acid from mixed cultures were 55ºC, 2 days HRT and pH 4.8-5.7, with pH-control once a day. The bioaugmentation strategy improved the results obtained in the prototype without applying reinoculation. Lactic acid was the main product along with other carboxylic acids. Further improvements are needed to increase purity as well as lactic acid concentration to reach economic feasibility of the whole process (digestion of OFMSW and downstream).

Enfoque sistémico del organismo: herramienta útil en la enseñanza de la anatomía humana / Systemic approach to the organism: a useful tool in teaching human anatomy

Fundamento: el estudio del cuerpo humano como un todo con enfoque sistémico constituye un aspecto esencial en la enseñanza de la Anatomía Humana en las carreras de las ciencias médicas. Objetivo: expresar la importancia del enfoque sistémico del cuerpo humano como un todo y su relación con los órganos y sistemas, en la enseñanza de la Anatomía Humana, en las carreras de las ciencias médicas. Métodos: se realizó una revisión bibliográfica de comunicaciones, artículos originales y de revisión, publicados en la última década (2010-2020) en revistas nacionales e internacionales indexadas en bases de datos reconocidas Scielo y Google Académico. Las principales palabras clave utilizadas fueron: enfoque sistémico, organismo humano, educación médica. Desarrollo: luego de la revisión documental realizada se expresó la importancia del enfoque sistémico del cuerpo humano como un todo y su relación con los órganos y sistemas en el estudio de la Anatomía Humana, lo que permitió reforzar la opinión de los autores al respecto fundamentalmente en relación a la necesidad de la enseñanza de dicha ciencia con este enfoque sistémico. Conclusiones: la dirección del proceso enseñanza aprendizaje de la Anatomía Humana, atendiendo a un enfoque de sistema, garantiza que el estudiante se forme con una concepción del organismo humano como un todo en estrecha relación con sus partes.

Background: the study of the human body as a whole with a systemic approach constitutes an essential aspect in the teaching of Human Anatomy in medical science careers. Objective: to express the importance of the systemic approach to the human body as a whole and its relationship with organs and systems, in the teaching of Human Anatomy, in medical science careers. Methods: a bibliographic review of research papers, original and review articles, published in the last decade (2010-2020) in national and international journals indexed in recognized databases Scielo and Google Scholar was carried out. The main keywords used were: systemic approach, human organism, medical education. Development: after the documentary review carried out, the importance of the systemic approach of the human body as a whole and its relationship with the organs and systems in the study of Human Anatomy was expressed, which allowed to reinforce the opinion of the authors in this regard fundamentally in in relation to the need to teach this science with this systemic approach. Conclusions: the direction of the teaching-learning process of Human Anatomy, taking into account a system approach, guarantees that the student is formed with a conception of the human organism as a whole in close relationship with its parts.

Unveiling Adatoms in On-Surface Reactions: Combining Scanning Probe Microscopy with van't Hoff Plots.

Scanning probe microscopy has become an essential tool to not only study pristine surfaces but also on-surface reactions and molecular self-assembly. Nonetheless, due to inherent limitations, some atoms or (parts of) molecules are either not imaged or cannot be unambiguously identified. Herein, we discuss the arrangement of two different nonplanar molecular assemblies of para-hexaphenyl-dicarbonitrile (Ph6(CN)2) on Au(111) based on a combined theoretical and experimental approach. For deposition of Ph6(CN)2 on Au(111) kept at room temperature, a rhombic nanoporous network stabilized by a combination of hydrogen bonding and antiparallel dipolar coupling is formed. Annealing at 575 K resulted in an irreversible thermal transformation into a hexagonal nanoporous network stabilized by native gold adatoms. However, the Au adatoms could neither be unequivocally identified by scanning tunneling microscopy nor by noncontact atomic force microscopy. By combining van't Hoff plots derived from our scanning probe images with our density functional theory calculations, we were able to confirm the presence of the elusive Au adatoms in the hexagonal molecular network.

Transmisión nosocomial comparada de los virus gripales / Comparative nosocomial transmission of influenza viruses

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Real-time surveillance systems: Applicability for the control of influenza in acute care.

BACKGROUND: The high morbidity and mortality caused by influenza viruses translate into a great impact on specialized health care. Apart from the annual vaccination, the relevance of other measures to prevent and control this infection is unknown. The objective of our research was to determine the importance of a real-time surveillance system to establish early extended transmission precautions. METHODS: Quasi-experimental before-and-after study comparing the influenza cases detected in hospitalized adults during the 2016/2017 season (264 patients) with those detected after the implementation of a real-time surveillance system in the 2017/2018 season (519 patients). The improvements included early microbiological diagnosis, immediate communication of results, constant updating of patient information, coordination among professionals, periodic surveillance of the adequacy of preventive measures, and greater control of roommates. The effectiveness of the intervention was determined from the nosocomial infection rate in each season. RESULTS: After the real-time surveillance system for influenza was implemented, patients with early microbiological diagnosis and immediate isolation increased significantly (13.7% vs 68.2%; P < .001). In addition, nosocomial infections decreased from 17% to 9.2% (P = .001) and overall hospital stay was significantly reduced. Assuming that the entire effect was due to the intervention, the absolute risk reduction was 7.8% and number needed to treat was 12.8. CONCLUSION: The results in our study reveal the impact of nosocomial transmission of influenza virus in a tertiary hospital and highlight the need to supplement traditional strategies with novel methodologies such as modern surveillance systems based on early diagnosis, close case monitoring, and coordination among professionals.

Hierarchy in the Halogen Activation During Surface-Promoted Ullmann Coupling.

Within the collection of surface-supported reactions currently accessible for the production of extended molecular nanostructures under ultra-high vacuum, Ullmann coupling has been the most successful in the controlled formation of covalent single C-C bonds. Particularly advanced control of this synthetic tool has been obtained by means of hierarchical reactivity, commonly achieved by the use of different halogen atoms that consequently display distinct activation temperatures. Here we report on the site-selective reactivity of certain carbon-halogen bonds. We use precursor molecules halogenated with bromine atoms at two non-equivalent carbon atoms and found that the Ullmann coupling occurs on Au(111) with a remarkable predilection for one of the positions. Experimental evidence is provided by means of scanning tunneling microscopy and core level photoemission spectroscopy, and a rationalized understanding of the observed preference is obtained from density functional theory calculations.

Local adsorption structure and bonding of porphine on Cu(111) before and after self-metalation.

We have experimentally determined the lateral registry and geometric structure of free-base porphine (2H-P) and copper-metalated porphine (Cu-P) adsorbed on Cu(111), by means of energy-scanned photoelectron diffraction (PhD), and compared the experimental results to density functional theory (DFT) calculations that included van der Waals corrections within the Tkatchenko-Scheffler approach. Both 2H-P and Cu-P adsorb with their center above a surface bridge site. Consistency is obtained between the experimental and DFT-predicted structural models, with a characteristic change in the corrugation of the four N atoms of the molecule's macrocycle following metalation. Interestingly, comparison with previously published data for cobalt porphine adsorbed on the same surface evidences a distinct increase in the average height of the N atoms above the surface through the series 2H-P, Cu-P, and cobalt porphine. Such an increase strikingly anti-correlates the DFT-predicted adsorption strength, with 2H-P having the smallest adsorption height despite the weakest calculated adsorption energy. In addition, our findings suggest that for these macrocyclic compounds, substrate-to-molecule charge transfer and adsorption strength may not be univocally correlated.

Preparación de profesores en ciencias médicas: una visión desde las páginas de EDUMECENTRO / Preparation of professors in medical sciences: a vision from the pages of EDUMECENTRO

La preparación sistemática del profesor en los aspectos científico-técnico, didáctico, filosófico, político-ideológico e informáticos es condición indispensable para emprender la función docente. Para cumplir con esta demanda, no solo debe dominar y estar actualizado en el contenido de su disciplina científica, sino que debe poseer una correcta preparación pedagógica para cumplir satisfactoriamente con sus funciones. En sus ediciones, la revista EDUMECENTRO ha contribuido a la preparación permanente de los docentes de las ciencias médicas, por lo que en el presente artículo se realiza una actualizada revisión de cómo, desde sus páginas, esta publicación seriada ha jugado un papel trascendental en la calidad de los procesos formativos en las ciencias médicas teniendo como premisa fundamental la preparación del profesor.

The systematic preparation of the teacher in the scientific-technical, didactic, philosophical, political-ideological and computing aspects is an indispensable condition to undertake the teaching function. To comply with this demand, professors not only must master and be updated in the content of their scientific disciplines, but also they must possess a correct pedagogical preparation. In its editions, the EDUMECENTRO magazine has contributed to the permanent preparation of medical sciences professors, so in this article an updated review of its pages is made, which manifests its effectiveness as a reference material at the disposal of the university professionals to improve the quality of training processes.

[Impact of nosocomial transmission of influenza virus in an acute hospital]. / Impacto de la transmisión nosocomial del virus de la gripe en un hospital de agudos.

OBJECTIVE: The increase in morbidity and mortality associated the influenza virus infections represents an important global challenge, with particular relevance within health institutions.The aim of the study was to highlight the impact, repercussions and characteristics of the nosocomial transmission of influenza virus. METHODS: A sample of 286 hospitalized patients in a third-level hospital with confirmed influenza (virus RNA in respiratory specimens) is included. The study design was observational, through the collection of positive microbiological results from the 2016-2017 season. A comparative statistical analysis was carried out between cases of community-acquired influenza and hospital-acquired cases. RESULTS: 14.3% of the total sample (41 cases) was considered of nosocomial origin. Significant differences were observed in the percentage of vaccinated between hospital-acquired (34.1%) and community-acquired (50.2%); and in the number of days of hospitalization after diagnosis between both groups. The attack rate was 0.66%. CONCLUSIONS: The nosocomial acquisition of the influenza virus resulted in a greater severity of the process and in the increase of days of hospital stay. Strict adherence to control measures and epidemiological surveillance of influenza cases has allowed to reduce the attack rate.

OBJETIVO: El incremento de la morbimortalidad asociado a la infección por el virus de la gripe supone un importante reto a nivel mundial, con especial relevancia dentro de las instituciones sanitarias. El objetivo del estudio fue analizar el impacto, repercusiones y características de la transmisión nosocomial del virus de la gripe. METODOS: Se incluyó una muestra de 286 pacientes hospitalizados en un centro de tercer nivel con gripe confirmada (ARN del virus en muestras respiratorias). El diseño del estudio fue observacional, mediante recogida de los resultados microbiológicos positivos de la temporada de gripe 2016-2017. Se realizó un análisis estadístico comparativo entre los casos de gripe comunitaria y los casos nosocomiales. RESULTADOS: El 14.3% del total de la muestra (41 casos) se consideró de origen nosocomial. Se observaron diferencias significativas en el porcentaje de vacunados entre los casos de infección nosocomial (34,1%) y comunitaria (50,2%), y en el número de días de ingreso tras diagnóstico (12 ±22 días para los casos nosocomiales y 6 ±8 días para los comunitarios). La tasa de ataque fue del 0,66%. CONCLUSIONES: La adquisición nosocomial del virus de la gripe se tradujo en una mayor gravedad del cuadro y en el incremento de los días de estancia hospitalaria. El estricto cumplimiento de las medidas de control y vigilancia epidemiológica de los casos de gripe ha permitido lograr una tasa de ataque reducida.

Layered Insulator/Molecule/Metal Heterostructures with Molecular Functionality through Porphyrin Intercalation.

Intercalation of molecules into layered materials is actively researched in materials science, chemistry, and nanotechnology, holding promise for the synthesis of van der Waals heterostructures and encapsulated nanoreactors. However, the intercalation of organic molecules that exhibit physical or chemical functionality remains a key challenge to date. In this work, we present the synthesis of heterostructures consisting of porphines sandwiched between a Cu(111) substrate and an insulating hexagonal boron nitride ( h-BN) monolayer. We investigated the energetics of the intercalation, as well as the influence of the capping h-BN layer on the behavior of the intercalated molecules using scanning probe microscopy and density functional theory calculations. While the self-assembly of the molecules is altered upon intercalation, we show that the intrinsic functionalities, such as switching between different porphine tautomers, are preserved. Such insulator/molecule/metal structures provide opportunities to protect organic materials from deleterious effects of atmospheric environment, can be used to control chemical reactions through spatial confinement, and give access to layered materials based on the ample availability of synthesis protocols provided by organic chemistry.

Impacto de la transmisión nosocomial del virus de la gripe en un hospital de agudos / Impact of nosocomial transmission of influenza virus in an acute hospital

Fundamentos: El incremento de la morbimortalidad asociado a la infección por el virus de la gripe supone un importante reto a nivel mundial, con especial relevancia dentro de las instituciones sanitarias. El objetivo del estudio fue analizar el impacto, repercusiones y características de la transmisión nosocomial del virus de la gripe. Métodos: Se incluyó una muestra de 286 pacientes hospitalizados en un centro de tercer nivel con gripe con firmada (ARN del virus en muestras respiratorias). El di seño del estudio fue observacional, mediante recogida de los resultados microbiológicos positivos de la temporada de gripe 2016-2017. Se realizó un análisis estadístico comparativo entre los casos de gripe comunitaria y los casos nosocomiales. Resultados: El 14.3% del total de la muestra (41 casos) se consideró de origen nosocomial. Se observaron diferencias significativas en el porcentaje de vacunados entre los casos de infección nosocomial (34,1%) y comunitaria (50,2%), y en el número de días de ingreso tras diagnóstico (12 ±22 días para los casos nosocomiales y 6 ±8 días para los comunitarios). La tasa de ataque fue del 0,66%. Conclusiones: La adquisición nosocomial del virus de la gripe se tradujo en una mayor gravedad del cuadro y en el incremento de los días de estancia hospitalaria. El estricto cumplimiento de las medidas de control y vigilancia epidemiológica de los casos de gripe ha permitido lograr una tasa de ataque reducida

Background: The increase in morbidity and mortality associated the influenza virus infections represents an important global challenge, with particular relevance within health institutions. The aim of the study was to highlight the impact, repercussions and characteristics of the nosocomial transmission of influenza virus. Methods: A sample of 286 hospitalized patients in a third-level hospital with confirmed influenza (virus RNA in respiratory specimens) is included. The study design was observational, through the collection of positive microbiological results from the 2016-2017 season. A comparative statistical analysis was carried out between cases of community-acquired influenza and hospital-acquired cases. Results: 14.3% of the total sample (41 cases) was considered of nosocomial origin. Significant differences were observed in the percentage of vaccinated between hospital-acquired (34.1%) and community-acquired (50.2%); and in the number of days of hospitalization after diagnosis between both groups. The attack rate was 0.66%. Conclusions: The nosocomial acquisition of the influenza virus resulted in a greater severity of the process and in the increase of days of hospital stay. Strict adherence to control measures and epidemiological surveillance of influenza cases has allowed to reduce the attack rate

Vértigo posicional paroxístico benigno, ese gran desconocido / Benign paroxysmal positional vertigo, the great unknown

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Física y educación para la salud: su pertinencia en la prevención de accidentes / Physics and health education: its pertinence in accidents prevention

Fundamento: la integración de la Física con la educación para la salud, a través de la prevención de los accidentes, es pertinente ya que estos constituyen una de las primeras causas de muerte en el planeta. Objetivo: elaborar un folleto didáctico con tareas docentes donde se integren la Física con la educación para la salud. Métodos: se realizó una investigación de desarrollo desde septiembre 2014 a junio 2015, en la Facultad de Tecnología de la Salud, de la Universidad de Ciencias Médicas de Villa Clara. Se aplicaron métodos teóricos: análisis-síntesis, inductivo-deductivo y sistémico-estructural; y empíricos: análisis documental de programas y plan calendario, observación a clases y la encuesta a profesores y alumnos; para constatar la integración o no de la Física con la educación para la salud; y el estadístico-matemático para los valores absolutos y relativos. Resultados: en el nivel de competencias declarado en los documentos no se contempla la mencionada integración, ni se precisa cómo lograrla en clases; los docentes reconocieron tener carencias metodológicas para ello y la bibliografía con que contaban estaba desactualizada, los alumnos declararon sentirse desmotivados, y opinaron que se debe cambiar la forma en que se recibe la disciplina, por lo que se elaboró un folleto didáctico que fue sometido a criterio de especialistas. Conclusiones: en él se establecen fundamentos teórico-metodológicos para la integración de la Física con la educación para la salud, a través de tareas docentes, por lo que fue valorado como adecuado por los especialistas.

Background: the integration of physics with health education, through the prevention of accidents is relevant since these constitute one of the leading causes of death on the planet. Objective: to elaborate a didactic brochure with teaching tasks where physics is integrated with health education. Methods: a developmental research was carried out from September 2014 to June 2015, in Villa Clara University of Medical Sciences Health Technology Faculty. Theoretical methods were applied: analysis-synthesis, inductive-deductive and systemic-structural; and empirical ones: documentary analysis of programs and calendar plan, observation to classes and the survey to teachers and students; to verify the integration of Physics with health education or not; and the statistical-mathematical for absolute and relative values. Results: the level of competence declared in the documents neither contemplate the above mentioned integration, nor it is stated how to achieve it in classes; The teachers acknowledged that there were methodological shortcomings and the bibliography they had was not updated, the students stated that they felt unmotivated, and felt that the way in which the discipline is taught should be changed, that´s why a didactic brochure was elaborated, which was valued by the expert´s criteria. Conclusions: it establishes theoretical-methodological foundations for the integration of physics with health education, through teaching tasks, so it was assessed as adequate by specialists.