Multi‐step processes catalysed by several catalysts working concurrently have been developed in nature, thus improving reaction efficiency. The quest for novel and improved catalytic systems has led ...to the development of biocatalytic and later to organocatalytic procedures as very valuable tools in asymmetric synthesis while using mild reaction conditions in the absence of metal catalysts. As a timeless challenge, chemists are facing the need for process designs in which different sorts of catalysts can operate successfully in a one‐pot concurrent fashion. Likewise, such designs bring about the best of each catalyst and, in certain cases, enable us to improve problematic issues, such as reactivity, selectivity, solubility, inhibition, etc. Specifically, to combine these two types of catalysts in one‐pot, achieving high yields and selectivity, is a fascinating aspect of catalysis. This review covers representative advances in this field, in particular those in which biocatalysts and organocatalysts are employed either in sequential reactions or in simultaneous processes.
A novel multicomponent chemoenzymatic strategy for the preparation of enantioenriched β-acyloxy thioethers has been developed. This robust methodology employs mild bases, air atmosphere, room ...temperature and avoids the use of foul-smelling thiols. Instead, potassium thioacetate is employed as a universal sulfur source. This chemoselective strategy tolerates aromatic and aliphatic components and diverse functional groups. The chirality is enzymatically defined by ADH-catalyzed bioreduction of α-haloketones delivering an enantioenriched halohydrin which is one of the three components, and the optical purity remains untouched in the final product. Semipreparative scale multicomponent reaction affords high yield of the products (up to 96%).
Aim
The knowledge of a species biogeographical patterns greatly enhances our understanding of geographical ecology, which can improve identifying key conservation needs. Yet, this knowledge is still ...scarce for many marine top predators. Here, we aim to analyse movement patterns and spatial structuring of a large predator, the short‐finned pilot whale Globicephala macrorhynchus, over a wide geographical area.
Location
North‐east Atlantic, in Macaronesian archipelagos (Azores, Madeira and Canaries) and Iberian Peninsula (Sagres).
Methods
We used likelihood techniques to estimate residency times and transition probabilities and carried out social analysis from individual photographic identification data, and analysed year‐round distribution from effort‐related sightings, collated between 1999 and 2015.
Results
The best‐fitting models included emigration and reimmigration and showed different residency times within each archipelago. A total of 26 individual movements from 21 individuals (from a sample of >2,300 individuals) were recorded between Madeira and the neighbouring archipelagos, and heterogeneous transition probabilities were estimated within and between areas. A social network diagram showed associations from animals with distinct residency patterns. Higher significant sighting rates were recorded during autumn in the Azores and Madeira.
Main conclusions
The variation in site fidelity and year‐round occupancy among areas of the Macaronesia is consistent with some degree of population structuring, which combined with a connectivity network and seasonal inflows from animals inhabiting offshore waters, support the development of a complex social and geographical ecology in short‐finned pilot whales. The combination of techniques applied in this study was an effective way to estimate parameters of movement, which could be a good practice to be used for other scenarios and species.
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•T. sanguinea LSR01 and T. villosa LSR02 produce biofoams from beer bagasse.•Biofoam production has potential in the valorization of brewery waste.•The mechanical stability of ...biofoams improves as laccase production increases.•Biofoams have residual laccase activity after drying oven process.•Biofoams can be used as green catalysts in biooxidation reactions.
White rot fungi are promising organisms for the production of mycelial-based biofoams, providing a sustainable means of valorizing lignocellulosic wastes. This study explores the utilization of two indigenous fungal species, isolated from Argentina and belonging to the genera Trametes, for producing biofoams from brewery waste. The resulting biofoams exhibited an average density of 0.30 g cm−3, a Young’s modulus of approximately 1 MPa, and a compressive stress of around 19 MPa. Additionally, the variation of laccase activity throughout the biofoam production process was evaluated. Surprisingly, residual laccase activity was detected in the biofoams following oven drying at temperatures of 60, 80, and 100 °C. This detection highlights the untapped enzymatic potential of the biofoams and positions them as promising green catalysts for various biotechnological applications.
The potential application of multistep continuous-flow systems has had a great impact on the syntheses of active pharmaceutical ingredients, natural products, and commodity chemicals. In this report, ...the highly efficient combination of a chemical reduction and a photochemical Csp2 –H activation reaction for selenylation of biologically relevant electron-rich arenes was achieved by means of a continuous-flow process. First, the reduction of alkyl and aryl selenocyanates by Rongalite was achieved giving the corresponding diselenides; second, the photoactivation of the Se–Se bond resulted in the selenylation of electron-rich arenes, both steps from good to excellent yields. In all cases, the reaction time was shortened, and isolated yields were improved when compared to batch reaction conditions. Furthermore, connecting both reactions in a multistep continuous-flow sequence was possible even when reductive and photooxidative transformations were coupled.
Given uncertain popularity of new products by location, fast fashion retailer Zara faces a trade-off. Large initial shipments to stores reduce lost sales in the critical first days of the product ...life cycle, but maintaining stock at the warehouse allows restocking flexibility once initial sales are observed. In collaboration with Zara, we develop and test a decision support system featuring a data-driven model of forecast updating and a dynamic optimization formulation for allocating limited stock by location over time. A controlled field experiment run worldwide with 34 articles during the 2012 season showed an increase in total average season sales by approximately 2% and a reduction in the number of unsold units at the end of the regular selling season by approximately 4%.
Wide-ranging connectivity patterns of common bottlenose dolphins (
) are generally poorly known worldwide and more so within the oceanic archipelagos of Macaronesia in the North East (NE) Atlantic. ...This study aimed to identify long-range movements between the archipelagos of Macaronesia that lie between 500 and 1,500 km apart, and between Madeira archipelago and the Portuguese continental shelf, through the compilation and comparison of bottlenose dolphin's photo-identification catalogues from different regions: one from Madeira (
= 363 individuals), two from different areas in the Azores (
= 495 and 176), and four from different islands of the Canary Islands (
= 182, 110, 142 and 281), summing up 1791 photographs. An additional comparison was made between the Madeira catalogue and one catalogue from Sagres, on the southwest tip of the Iberian Peninsula (
= 359). Results showed 26 individual matches, mostly between Madeira and the Canary Islands (
= 23), and between Azores and Madeira (
= 3). No matches were found between the Canary Islands and the Azores, nor between Madeira and Sagres. There were no individuals identified in all three archipelagos. The minimum time recorded between sightings in two different archipelagos (≈ 460 km apart) was 62 days. Association patterns revealed that the individuals moving between archipelagos were connected to resident, migrant and transient individuals in Madeira. The higher number of individuals that were re-sighted between Madeira and the Canary Islands can be explained by the relative proximity of these two archipelagos. This study shows the first inter-archipelago movements of bottlenose dolphins in the Macaronesia region, emphasizing the high mobility of this species and supporting the high gene flow described for oceanic dolphins inhabiting the North Atlantic. The dynamics of these long-range movements strongly denotes the need to review marine protected areas established for this species in each archipelago, calling for joint resolutions from three autonomous regions belonging to two EU countries.
El presente artículo expone un análisis lingüístico e interpretativo sobre el uso de la metáfora conceptual en el campo de la salud mental, tomando como campo de observación el uso de Twitter en la ...primera edición del Día del Orgullo Loco en España, celebrada el 20 de mayo de 2018. El objetivo es dar cuenta de los posicionamientos expresados por los activistas en primera persona. Los resultados muestran un cuestionamiento a las lógicas coercitivas producidas por la atención psiquiátrica, una problematización del modelo hegemónico en su conjunto, una denuncia a la opresión que implica el estigma, problemas de comunicación y demandas de mayor diálogo con los profesionales del campo de la salud mental. Este análisis nos ha permitido comprender el modo lingüístico de re-semantizar el campo de la salud mental, así como dar cuenta de las tensiones existentes entre las percepciones subjetivas de las personas diagnosticadas y las producciones del modelo médico hegemónico.
A preparation of β-ketosulfides avoiding the use of thiols is described. The combination of a multicomponent reaction and a lipase-catalysed hydrolysis has been developed in order to obtain high ...chemical diversity employing a single sulfur donor. This methodology for the selective synthesis of a set of β-ketosulfides is performed under mild conditions and can be set up in one-pot two-step and on a gram-scale.
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