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1.
ChemSusChem ; : e202400759, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38818644

RESUMEN

A new and practical method for the thermal degradation of technically relevant bio-based lignin is presented. By heating a solution of lignin in highly concentrated caustic potash, vanillic acid is almost exclusively obtained in yields up to 10.6 wt%. By altering the reaction parameters, the selectivity of the reaction can be shifted towards the demethylation product, protocatechuic acid, which is obtained in a yield of 6.9 wt%. Furthermore, the procedure was applicable to different types of Kraft and organosolv lignin. To create an economically feasible process, ion exchange resins were used for the work-up of the highly caustic reaction media without neutralizing the complete mixture. By the selective removal of the desired vanillic acid from the caustic potash, this alkaline media could directly be reused for at least 5 further lignin degradations without significant loss of yield.

2.
ChemSusChem ; 16(8): e202202300, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-36651115

RESUMEN

A sustainable electrochemical pathway for degradation and thermal treatment of technical lignosulfonate is presented. This approach is an opportunity to produce remarkable quantities of low molecular weight compounds, such as vanillin and acetovanillone. For the electrochemical degradation, a simple two-electrode arrangement in aqueous media is used, which is also easily scalable. The oxidation of the biopolymer occurs at the anode whereas hydrogen is evolved at the cathode. The subsequent thermal treatment supports the degradation of the robust chemical structure of lignosulfonates. With optimized electrolytic conditions, vanillin could be obtained in 9.7 wt% relative to the dry mass of lignosulfonate used. Aside from vanillin, by-products such as acetovanillone or vanillic acid were observed in lower yields. A new and reliable one-pot, two-step degradation of different technically relevant lignosulfonates is established with the advantages of using electrons as an oxidizing agent, which results in low quantities of reagent waste.

3.
J Genet Couns ; 21(3): 462-8, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22544369

RESUMEN

The field of genetic counseling faces a broad challenge: many potential clients may not be aware of the value and benefit of genetic counseling services, and therefore may not utilize those services. Navigenics is a personal genomic testing company that provides telephonic genetic counseling services for multifactorial diseases and pharmacogenetics. When first offered in 2008, utilization of the Navigenics genetic counseling service was less than expected. To explore the basis for under-utilization and potential mechanisms for increasing uptake, Navigenics initiated a quality improvement study, in which three different methods of engaging clients in the uptake of genetic counseling services were assessed over the course of 1 year. Outcomes showed significant differences in uptake rates between methodologies (7.5%, 24.6%, and 60.1%), yielding an 8-fold increase in service utilization when post-test telephonic outreach to all clients was performed. Further, utilization spanned all risk levels based on client results, evidence that not only clients with high-risk results were motivated to engage in the genetic counseling service. This research indicates that implementing strategies to educate clients about genetic counseling can positively impact client engagement and utilization of available services.


Asunto(s)
Asesoramiento Genético , Genómica , Teléfono , Humanos
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