In recent years, a novel medium with similar properties to ionic liquids but with additional advantages regarding cost, environmental impact, and synthesis has been developed: deep eutectic solvents ...(DESs). These solvents result from the association between an organic salt (ammonium or phosphonium) with a hydrogen‐bond donor such as alcohols, acids, or amides. To date, the availability of green, inexpensive and easy to handle solvents is almost non‐existent. Therefore, DESs currently arouse growing interest in many research fields. This review deals with the major applications of this new family of solvents with a particular focus on lipase‐catalyzed reactions such as hydrolysis, aminolysis, or alcoholysis.
Due to a growing interest in green technologies, the Deep Eutectic Solvents (DESs) are now rapidly emerging and may be considered as a serious alternative to conventional organic solvents in various applications. Thus, this review aimed at giving an overview of their synthesis, their characteristics and their main applications, with an exhaustive focus on lipase‐catalyzed reactions.
► Specific activity and stability of iCALB in deep eutectic solvents were studied. ► Some DESs can react and compete with the substrates in alcoholysis reactions. ► Reactivity for alcoholysis in deep ...eutectic mixtures may depend on the polarity of the nucleophilic substrate.
This study aimed at analyzing the advantages and limitations of several deep eutectic solvents (DESs) as ‘green solvents’ for biotransformation using immobilized Candida antarctica lipase B as catalyst. The transesterification of vinyl laurate was chosen as model reaction and the influence of substrate polarity was assessed using alcohols of various chain lengths. Results showed that grinding of immobilized lipase was essential parameters for good lipase activity. Moreover, in our model reaction some hydrogen-bond donor component from the DES can compete with the alcoholysis reaction. Indeed, side reactions were observed with DES based on dicarboxylic acid or ethylene glycol, leading to some limitations of their use. However, the results showed that other DESs such as choline chloride:urea and choline chloride:glycerol could exhibit high activity and selectivity making them promising solvents for lipase-catalyzed reactions. Finally, the best DES's specific activity – and stability up to five days incubation time – were analyzed and compared with conventional organic solvents. Experiments revealed that iCALB is less influenced by the chain length of alcohol in DES than organic solvents and it is preserves its activity with minimally destructive to protein structure.
This forum reviews youth literature from around the world to examine the diverse settings and social, historical, and political contexts that shape youth identities and experiences.
This forum reviews youth literature from around the world to examine the diverse settings and social, historical, and political contexts that shape youth identities and experiences.
Genetic admixture of distinct gene pools is the consequence of complex spatiotemporal processes that could have involved massive migration and local mating during the history of a species. However, ...current methods for estimating individual admixture proportions lack the incorporation of such a piece of information. Here, we extend Bayesian clustering algorithms by including global trend surfaces and spatial autocorrelation in the prior distribution on individual admixture coefficients. We test our algorithm by using spatially explicit and realistic coalescent simulations of colonization followed by secondary contact. By coupling our multiscale spatial analyses with a Bayesian evaluation of model complexity and fit, we show that the algorithm provides a correct description of smooth clinal variation, while still detecting zones of sharp variation when they are present in the data. We also apply our approach to understand the population structure of the killifish, Fundulus heteroclitus, for which the algorithm uncovers a presumed contact zone in the Atlantic coast of North America.
This forum reviews youth literature from around the world to examine the diverse settings and social, historical, and political contexts that shape youth identities and experiences.
This forum reviews youth literature from around the world to examine the diverse settings and social, historical, and political contexts that shape youth identities and experiences.
The historical evolution of incidence and outcome of cardiogenic shock (CS) in acute myocardial infarction (AMI) patients is debated. This study compared outcomes in AMI patients from 1995 to 2005, ...according to the presence of CS.
Three nationwide French registries were conducted 5 years apart, using a similar methodology in consecutive patients admitted over a 1-month period. All 7531 AMI patients presenting ≤48 h of symptom onset were included. The evolution of mortality was compared in the 486 patients with CS vs. those without CS. The incidence of CS tended to decrease over time (6.9% in 1995; 5.7% in 2005, P = 0.07). Thirty-day mortality was considerably higher in CS patients (60.9 vs. 5.2%). Over the 10-year period, mortality decreased for both patients with (70-51%, P = 0.003) and without CS (9-4%, P < 0.001). In CS patients, the use of percutaneous coronary intervention (PCI) increased from 20 to 50% (P < 0.001). Time period was an independent predictor of early mortality in CS patients (OR for death, 2005 vs. 1995 = 0.45; 95% CI: 0.27-0.75, P = 0.005), along with age, diabetes, and smoking status. When added to the multivariate model, PCI was associated with decreased mortality (OR = 0.38; 95% CI: 0.24-0.58, P < 0.001). In propensity-score-matched cohorts, CS patients with PCI had a significantly higher survival.
Cardiogenic shock remains a clinical concern, although early mortality has decreased. Improved survival is concomitant with a broader use of PCI and recommended medications at the acute stage. Beyond the acute stage, however, 1-year survival has remained unchanged.
In the wake of the SARS-CoV-2 pandemic and unprecedented global demand, clinicians are struggling to source adequate access to personal protective equipment. Respirators can be in short supply, ...though are necessary to protect workers from SARS-CoV-2 exposure. Rapid decontamination and reuse of respirators may provide relief for the strained procurement situation.
In this study, we investigated the suitability of 70°C dry heat and microwave-generated steam (MGS) for reprocessing of FFP2/N95-type respirators, and Type-II surgical face masks. Staphylococcus aureus was used as a surrogate as it is less susceptible than enveloped viruses to chemical and physical processes.
We observed >4 log10 reductions in the viability of dry S. aureus treated by dry heat for 90 min at 70°C and >6 log10 reductions by MGS for 90 s. After 3 reprocessing cycles, neither process was found to negatively impact the bacterial or NaCl filtration efficiency of the respirators that were tested. However, MGS was incompatible with Type-II surgical masks tested, as we confirmed that bacterial filtration capacity was completely lost following reprocessing. MGS was observed to be incompatible with some respirator types due to arcing observed around some types of metal nose clips and by loss of adhesion of clips to the mask.
Considering the advantages and disadvantages of each approach, we propose a reprocessing personal protective equipment/face mask workflow for use in medical areas.
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