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1.
Front Psychol ; 15: 1359687, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558784

RESUMO

The International Association for the Study of Pain (IASP) revised its definition of pain to "an unpleasant sensory and emotional experience." Three recent recommendations for understanding pain if there are no clear brain correlates include eliminativism, multiple realizability, and affordance-based approaches. I adumbrate a different path forward. Underlying each of the proposed approaches and the new IASP definition is the suspicion that there are no specific correlates for pain. I suggest that this basic assumption is misguided. As we learn more about brain function, it is becoming clear that many areas process many different types of information at the same time. In this study, I analogize how animal brains navigate in three-dimensional space with how the brain creates pain. Underlying both cases is a large-scale combinatorial system that feeds back on itself through a diversity of convergent and divergent bi-directional connections. Brains are not like combustion engines, with energy driving outputs via the structure of the machine, but are instead more like whirlpools, which are essentially dynamic patterns in some substrates. We should understand pain experiences as context-dependent, spatiotemporal trajectories that reflect heterogeneous, multiplex, and dynamically adaptive brain cells.

2.
Front Reprod Health ; 6: 1298615, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559324

RESUMO

Introduction: Exposure to endocrine disrupting chemicals (EDCs), such as phthalates, can negatively impact maternal and child health, contributing to impaired fetal growth, preterm birth, and pregnancy complications, as well as increased downstream risks of cardiometabolic disease and breast cancer. Notably, women of color (WOC) are the largest consumers of personal care products, which are a common source of EDC exposure. Methods: The Let's Reclaim Our Ancestral Roots (Let's R.O.A.R) Pilot Study developed an educational intervention delivered during pregnancy to promote reduced use of phthalate-containing hair care products (HCPs). This mixed-methods study included: (1) a quantitative analysis and (2) a qualitative analysis of the educational sessions and the semi-structured focus groups to evaluate the factors that influenced the hair care practices and product choices of WOC at various stages of life, including their current pregnancy (hereafter referred to as the hair journey). During the sessions, participants learned about EDCs (with a focus on phthalates), the unequal burden of exposure for WOC, adverse implications of exposure, and exposure reduction strategies. Focus group sessions provided insight into participants' hair journeys from childhood to the current pregnancy and explored factors during their hair product selection process. All sessions were transcribed and imported into NVivo Version 12 for coding and thematic analysis. Results: A total of 46 individuals were enrolled in the study, and 31 participated in an educational session. This current work synthesizes the qualitative analysis of this study. We identified two important life stages (before and after gaining agency over hair care practices and product choices) and three dominant themes related to HCP use: (1) products that impacted the hair journey, which involved all mentions of hair products, (2) factors that influenced the hair journey, which included individuals or entities that shaped participants' hair experiences, and (3) the relationship between hair and sense of self, where sense of self was defined as the alignment of one's inner and outer beauty. Conclusion: The themes intersected and impacted the participants' hair journey. Cultural integration was a sub-theme that overlapped within the dominant themes and participants discussed the effect of traditions on their hair experiences.

3.
J Orthop Case Rep ; 14(3): 44-49, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38560297

RESUMO

Introduction: Non-ossifying fibroma (NOF) is a common benign fibrogenic bone lesion commonly found in the metaphysis of long bones. While small NOFs are typically asymptomatic and left untreated, large NOFs are often associated with pathologic fractures that can be treated conservatively or operatively. To our knowledge, the NOF presented in this case report is one of the largest reported in the literature. Case Report: We present a case of a 12-year-old Hispanic female who presented to our institution after falling off a horse and landing on her right leg and wrist. Radiographs revealed a right distal femur fracture through an unusually large lytic bone lesion. The patient was treated with curettage, grafting, open reduction, and internal fixation, given the unstable and pathological nature of the fracture. Conclusion: This case substantiates the literature that large fractures through a NOF can be appropriately managed operatively. However, orthopedic surgeons should be aware of the risks of surgery, including infection, when considering operative management of patients who present with large unstable pathologic fractures through a NOF.

4.
J Orthop Case Rep ; 14(3): 25-28, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38560332

RESUMO

Introduction: The incidence of ipsilateral fracture of the shaft of the femur and dislocation of the hip are extremely rare injuries. However, the incidence of complex fractures is increasing day by day due to an increasing variety of traumatic mechanisms. This type of injury constitutes various diagnostic and treatment difficulties for the surgeon. Such injuries should be managed on an urgent basis for better functional outcomes. Case Report: We hereby describe two such cases: First case hip was reduced using external fixator pins, stabilization of the shaft femur fracture was done with an external fixator and the second case hip was reduced with bone holding clamps and the shaft femur fracture was fixed with interlocking nail. Conclusion: Fixator-assisted closed reductions are the first line of treatment in the management of posterior dislocation hip complicated with ipsilateral femoral shaft fractures. If closed reduction fails, fracture site can be opened and direct forces can be applied to the proximal femur to aid hip reduction with minimum complications.

5.
mSystems ; : e0025024, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38564716

RESUMO

Most biosynthetic gene clusters (BGC) encoding the synthesis of important microbial secondary metabolites, such as antibiotics, are either silent or poorly expressed; therefore, to ensure a strong pipeline of novel antibiotics, there is a need to develop rapid and efficient strain development approaches. This study uses comparative genome analysis to instruct rational strain improvement, using Streptomyces rimosus, the producer of the important antibiotic oxytetracycline (OTC) as a model system. Sequencing of the genomes of two industrial strains M4018 and R6-500, developed independently from a common ancestor, identified large DNA rearrangements located at the chromosome end. We evaluated the effect of these genome deletions on the parental S. rimosus Type Strain (ATCC 10970) genome where introduction of a 145 kb deletion close to the OTC BGC in the Type Strain resulted in massive OTC overproduction, achieving titers that were equivalent to M4018 and R6-500. Transcriptome data supported the hypothesis that the reason for such an increase in OTC biosynthesis was due to enhanced transcription of the OTC BGC and not due to enhanced substrate supply. We also observed changes in the expression of other cryptic BGCs; some metabolites, undetectable in ATCC 10970, were now produced at high titers. This study demonstrated for the first time that the main force behind BGC overexpression is genome rearrangement. This new approach demonstrates great potential to activate cryptic gene clusters of yet unexplored natural products of medical and industrial value.IMPORTANCEThere is a critical need to develop novel antibiotics to combat antimicrobial resistance. Streptomyces species are very rich source of antibiotics, typically encoding 20-60 biosynthetic gene clusters (BGCs). However, under laboratory conditions, most are either silent or poorly expressed so that their products are only detectable at nanogram quantities, which hampers drug development efforts. To address this subject, we used comparative genome analysis of industrial Streptomyces rimosus strains producing high titers of a broad spectrum antibiotic oxytetracycline (OTC), developed during decades of industrial strain improvement. Interestingly, large-scale chromosomal deletions were observed. Based on this information, we carried out targeted genome deletions in the native strain S. rimosus ATCC 10970, and we show that a targeted deletion in the vicinity of the OTC BGC significantly induced expression of the OTC BGC, as well as some other silent BGCs, thus suggesting that this approach may be a useful way to identify new natural products.

6.
Angew Chem Int Ed Engl ; : e202319470, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566301

RESUMO

Two-electron oxygen reduction reaction (2e- ORR) is a promising method for the synthesis of hydrogen peroxide (H2O2). However, high energy barriers for the generation of key *OOH intermediates hinder the process of 2e- ORR. Herein, we prepared a copper-supported indium selenide catalyst (Cu/In2Se3) to enhance the selectivity and yield of 2e- ORR by employing an electronic metal-support interactions (EMSIs) strategy. EMSIs-induced charge rearrangement between metallic Cu and In2Se3 is conducive to *OOH intermediate generation, promoting H2O2 production. Theoretical investigations reveal that the inclusion of Cu significantly lowers the energy barrier of the 2e- ORR intermediate and impedes the 4e- ORR pathway, thus favoring the formation of H2O2. The concentration of H2O2 produced by Cu/In2Se3 is ~2 times than In2Se3, and Cu/In2Se3 shows promising applications in antibiotic degradation. This research presents a valuable approach for the future utilization of EMSIs in 2e- ORR.

7.
Angew Chem Int Ed Engl ; : e202404766, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38567502

RESUMO

The single-atom Fe-N-C is a prominent material with exceptional reactivity in areas of sustainable energy and catalysis research. It is challenging to obtain the dense Fe-N4 site without the Fe nanoparticle (NPs) sintering during the Fe-N-C synthesis via high-temperature pyrolysis. Thus, a novel approach is devised for the Fe-N-C synthesis at low temperatures. Taking FeCl2 as Fe source, a hydrogen environment can facilitate oxygen removal and dechlorination processes in the synthesis, efficiently favouring Fe-N4 site formation without Fe nanoparticle clustering at as low as 360 °C. We shed light on the reaction mechanism about hydrogen promoting Fe-N4 formation in the synthesis. By adjusting the temperature and duration, the Fe-N4 structural evolution and site density can be precisely tuned to directly influence the catalytic behavior of the Fe-N-C material. The FeNC-H2-360 catalyst demonstrates a remarkable Fe dispersion (8.3 wt%) and superior acid ORR activity with a half-wave potential of 0.85 V and a peak power density of 1.21 W cm-2 in fuel cell. This method also generally facilitates the synthesis of various high-performance M-N-C materials (M = Fe, Co, Mn, Ni, Zn, Ru) with elevated single-atom loadings.

8.
Chemphyschem ; : e202300991, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38568155

RESUMO

We conducted ab-initio calculations to investigate a class of materials with the goal of enabling nitrogen activation and electrochemical ammonia production under ambient conditions. The source of protons at the anode could originate from either water splitting or H2, but our specific focus was on the cathode reaction, where nitrogen is reduced into ammonia. The conventional associative, dissociative, and Mars-van Krevelen mechanisms were investigated on the (111) facets of a range of metal carbonitrides. We explored the catalytic activity by calculating the free energy of all intermediates along the reaction pathway and constructing free energy diagrams to identify the steps determining the reaction's feasibility. We closely examined the potential for catalyst poisoning within the electrochemical environment, considering the bias required to drive the reaction. Furthermore, we assessed the likelihood of catalyst decomposition and the potential for catalyst regeneration among the most intriguing carbonitrides. Our findings revealed only NbCN exhibits both activity and stability, capable of self-regeneration and nitrogen-to-ammonia activation, with a low potential-determining step energy of 0.58 eV. This material can facilitate ammonia formation via a mixed associative-MvK mechanism. In contrast, other carbonitrides of this crystallographic orientation are likely to undergo decomposition, reverting to their parent metals under operational conditions.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38558343

RESUMO

Here, polyaniline/polyvinylidene fluoride (PANI/PVDF) nanofiber composite membrane was fabricated using electrostatic spinning technology to remove hexavalent chromium Cr(VI). The employment of PANI not only extremely enhanced the hydrophilic property of the nanofiber membrane, but also facilitated the transfer of Cr2O72- from water to the membrane. The PANI/PVDF membrane had an extremely excellent performance in getting rid of Cr(VI) and a quite large flux (250 L/m2 h). The maximum adsorption quantity of the membrane could reach 334.5 mg/g in which adsorption played 52.12% part and reduction played 47.87% part. The removal rate could reach nearly 100% immediately in the permeate solution under filtration while it needed 240 min to reach 100% only by static adsorption. Therefore, the interception of the membrane and the adsorption reduction of PANI had synergistic effect on removal of Cr(VI). Furthermore, the removal rate of Cr(VI) could still reach 95.97% after reused 8 times. The membrane showed a very good reusability and application prospect.

10.
Addiction ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561602

RESUMO

BACKGROUND AND AIMS: People who inject drugs (PWID) are at risk for adverse outcomes across multiple dimensions. While evidence-based interventions are available, services are often fragmented and difficult to access. We measured the effectiveness of an integrated care van (ICV) that offered services for PWID. DESIGN, SETTING AND PARTICIPANTS: This was a cluster-randomized trial, which took place in Baltimore, MD, USA. Prior to randomization, we used a research van to recruit PWID cohorts from 12 Baltimore neighborhoods (sites), currently served by the city's mobile needle exchange program. INTERVENTION AND COMPARATOR: We randomized sites to receive weekly visits from the ICV (n = 6) or to usual services (n = 6) for 14 months. The ICV offered case management; buprenorphine/naloxone; screening for HIV, hepatitis C virus and sexually transmitted infections; HIV pre-exposure prophylaxis; and wound care. MEASUREMENTS: The primary outcome was a composite harm mitigation score that captured access to evidence-based services, risk behaviors and adverse health events (range = 0-15, with higher numbers indicating worse status). We evaluated effectiveness by comparing changes in the composite score at 7 months versus baseline in the two study arms. FINDINGS: We enrolled 720 cohort participants across the study sites (60 per site) between June 2018 and August 2019: 38.3% women, 72.6% black and 85.1% urine drug test positive for fentanyl. Over a median of 10.4 months, the ICV provided services to 734 unique clients (who may or may not have been cohort participants) across the six intervention sites, including HIV/hepatitis C virus testing in 577 (78.6%) and buprenorphine/naloxone initiation in 540 (74%). However, only 52 (7.2%) of cohort participants received services on the ICV. The average composite score decreased at 7 months relative to baseline, with no significant difference in the change between ICV and usual services (difference in differences: -0.31; 95% confidence interval: -0.70, 0.08; P = 0.13). CONCLUSIONS: This cluster-randomized trial in Baltimore, MD, USA, found no evidence that weekly neighborhood visits from a mobile health van providing injection-drug-focused services improved access to services and outcomes among people who injected drugs in the neighborhood, relative to usual services. The van successfully served large numbers of clients but unexpectedly low use of the van by cohort participants limited the ability to detect meaningful differences.

11.
Ann R Coll Surg Engl ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563063

RESUMO

INTRODUCTION: When using radiation intraoperatively, a surgeon should aim to keep the radiation dose as low as is reasonably achievable to obtain the therapeutic goal. We aimed to investigate factors associated with increased radiation exposure in fixation of proximal femur fractures. METHODS: We assessed 369 neck of femur fractures over a 1-year period in a district general hospital. All hip fracture subtypes that had undergone surgical fixation were included. We assessed the relationship between type of fracture, implants used and surgeon level of experience with the dose-area product (DAP; cGy/cm2) and screening time (dS). We also looked at the quality of reduction and fixation and its effect on the radiation exposure. RESULTS: A total of 184 patients were included in our analysis; 185 patients who were treated with hip arthroplasty were excluded. There was a significant association between higher DAP and fracture subtype (p = 0.001), fracture complexity (p < 0.001), if an additional implant was used (p = 0.001), if fixation was satisfactory (p = 0.002) and operative time (p < 0.001). DAP was higher with a proximal femoral nail than with a dynamic hip screw, especially when a long nail was used. There was some evidence of an association between the surgeon's level of experience and DAP exposure, although this was not statistically significant (p = 0.069). CONCLUSIONS: Increased radiation in proximal femur fractures is seen in the fixation of complex fractures, some subtypes, with certain types of implants used and if an additional implant was required. Surgeon seniority did not result in less radiation exposure, which is in contrast to other published studies.

12.
J Adv Nurs ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563492

RESUMO

AIMS: To explore healthcare professionals' perceptions and experiences of take-home naloxone initiatives in acute care settings to gain an understanding of issues facilitating or impeding dispensing. DESIGN: Systematic literature review. DATA SOURCES: Cochrane, MEDLINE and CINAHL were searched from 15/03/2021 to 18/03/2021, with a follow-up search performed via PubMed on 22/03/2021. The years 2011 to 2021 were included in the search. REVIEW METHODS: A systematic literature review focused on qualitative studies and quantitative survey designs. Synthesis without meta-analysis was undertaken using a thematic analysis approach. RESULTS: Seven articles from the United States of America (5), Australia (1) and Canada (1) with 750 participants were included in the review. Results indicate ongoing stigma towards people who use drugs with preconceived moral concerns regarding take-home naloxone. There was confusion regarding roles and responsibilities in take-home naloxone dispensing and patient education. Similarly, there was a lack of clarity over logistical and financial issues. CONCLUSION: Take-home naloxone is a vital harm reduction initiative. However, barriers exist that prevent the optimum implementation of these initiatives. IMPACT: What is already known: Deaths due to opioid overdose are a global health concern, with take-home naloxone emerging as a key harm reduction scheme. Globally, less than 10% of people who use drugs have access to treatment initiatives, including take-home naloxone. An optimum point of distribution of take-home naloxone is post-acute hospital care. WHAT THIS PAPER ADDS: There is role confusion regarding responsibility for the provision of take-home naloxone and patient education. This is exacerbated by inconsistent provision of training and education for healthcare professionals. Logistical or financial concerns are common and moral issues are prevalent with some healthcare professionals questioning the ethics of providing take-home naloxone. Stigma towards people who use drugs remains evident in some acute care areas which may impact the use of this intervention. Implications for practice/policy: Further primary research should examine what training and education methods are effective in improving the distribution of take-home naloxone in acute care. Education should focus on reduction of stigma towards people who use drugs to improve the distribution of take-home naloxone. Standardized care guidelines may ensure interventions are offered equally and take-home naloxone 'champions' could drive initiatives forward, with support from harm reduction specialists. REPORTING METHOD: This has adhered to the PRISMA reporting guidelines for systematic reviews. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

13.
J Comput Chem ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563509

RESUMO

This article describes a density functional theory (DFT) study to explore a bio-inspired NiFe complex known for its experimental activity in electro-reducing CO2 to CH4 when adsorbed on graphite. The coordination properties of the complex are investigated in isolated form and when physisorbed on a graphene surface. A comparative analysis of DFT approaches for surface modeling is conducted, utilizing either a finite graphene flake or a periodic carbon surface. Results reveal that the finite model effectively preserves all crucial properties. By examining predicted structures arising from CO2 insertion within the mono-reduced NiFe species, whether isolated or adsorbed on the graphene flake, a potential species for subsequent electro-reduction steps is proposed. Notably, the DFT study highlights two positive effects of complex adsorption: facile electron transfers between graphene and the complex, finely regulated by the complex state, and a lowering of the thermodynamic demand for CO2 insertion.

14.
Artigo em Inglês | MEDLINE | ID: mdl-38564127

RESUMO

Microbial nitrate reduction processes involve two competing pathways: denitrification (DEN) and dissimilatory nitrate reduction to ammonium (DNRA). This study investigated the distribution of DNRA in a sole sulfur-driven nitrogen conversion process using a laboratory-scale sequencing biofilm batch reactor (SBBR) through a series of batch tests with varying sulfide/nitrate (S/N) ratios. The results showed that DNRA became more dominant in the sulfide-oxidizing autotrophic denitrification (SOAD) process as the S/N ratio increased to 1.5:1, 1.7:1, and 2:1, reaching a peak of 35.3% at the S/N ratio of 1.5:1. Oxidation-reduction potential (ORP) patterns demonstrated distinct inflection points for nitrate and nitrite consumption under the SOAD-only conditions, whereas these points overlapped when DNRA coexisted with SOAD. Analysis of 16S ribosomal RNA identified Ignavibacterium, Hydrogenophaga, and Geobacter as the dominant genera responsible for DNRA during autotrophic nitrate reduction. The findings of the DNRA divergence investigation provided valuable insights into enhancing biological nitrogen removal processes, particularly when coupled with the anammox.

16.
Chemistry ; : e202304003, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573800

RESUMO

Proton exchange membrane fuel cells (PEMFCs) and alkaline membrane fuel cells (AEMFCs) have received great attention as the energy device of next generation. Accelerating oxygen reduction reaction (ORR) kinetics is the key to improve PEMFCs and AEMFCs performance. Platinum-based catalysts are the most widely used catalysts for ORR, but their high price and low abundance limit the commercialization of fuel cell. Non-noble metal-nitrogen-carbon (M-N-C) is considered to be the most likely material to replace Pt-based catalysts, among which Fe-N-C and Co-N-C have been widely studied due to their excellent intrinsic ORR performance and have made great progress in the past decades. With the improvement of synthesis technology and deepening understanding of the ORR mechanism, some reported Fe-N-C and Co-N-C catalysts have shown excellent ORR activity close to that of commercial Pt/C catalysts. Inspired by the progress, regulation strategies on Fe-N-C or Co-N-C catalysts are summarized in this review from 5 aspects: (1) coordinated atoms, (2) environmental heteroatoms and defects, (3) dual-metal active sites, (4) metal-based particle promoter and (5) curved carbon layer. Next, we make our own suggestions on some challenges facing Fe-N-C and Co-N-C research.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38575787

RESUMO

This study aims to determinate the correlation between tobacco control policies (TCP) and the prevalence of tobacco use in the 32 Mexican states during the 2016-2017 period. This is an ecological study that measured TCP by the Tobacco Control Scale (TCS) which assigns a score (0-100) based on the level of these component's implementation: price, prohibition in public spaces, expenditures of public information campaigns, publicity prohibitions, health warnings, and treatments. We analyzed the associations between the TCS scores and prevalence of tobacco use extracted from the National Survey of Drug, Alcohol and Tobacco Consumption using Spearman correlations. Prevalence of daily smokers is negatively correlated with global TCS scores for adolescents (p = 0.026). Price showed similar negative correlations with daily prevalence in adolescents (p = 0.003), adults (p = 0.040), men (p < 0.006), and women (p = 0.040). Many Mexican states need to improve on tobacco control policies, especially targeting a key population: adolescents.

18.
J Res Adolesc ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576095

RESUMO

Research shows positive bystander intervention effectively mitigates bullying experiences. Yet, more evidence regarding bystander responses to bias-based social exclusion (BSE) is needed in intergroup contexts, especially in the majority world and in areas of intractable conflict. This study assessed the effectiveness of skills and skills + contact-based interventions for BSE among 148 Palestinian Citizens of Israel (Mage = 10.55) and 154 Jewish-Israeli (Mage = 10.54) early adolescents (Girls = 52.32%) in Tel Aviv-Yafo. Bystander responses were assessed by participants' reactions to hypothetical BSE scenarios over three time points. Repeated measures ANOVAs revealed both interventions significantly increased positive and decreased negative bystander responses, with changes maintained at the follow-up. The opposite result pattern emerged for the control group. Findings suggest that both interventions can effectively encourage youth to publicly challenge BSE, even amidst intractable conflict.

19.
Angew Chem Int Ed Engl ; : e202401185, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576259

RESUMO

The electrocatalytic conversion of CO2 into multi-carbon (C2+) products provides an attractive route for storing intermittent renewable electricity as fuels and feedstocks with high energy densities. Although substantial progress has been made in selective electrosynthesis of C2+ products via engineering the catalyst, rational design of the local reaction environment in the vicinity of catalyst surface also acts as an effective approach for further enhancing the performance. Here, we discuss recent advances and pertinent challenges in the modulation of local reaction environment, encompassing local pH, the choice of the species and concentrations of cations and anions as well as local reactant/intermediate concentrations, for achieving high C2+ selectivity. In addition, mechanistic understanding in the effects of the local reaction environment is also discussed. Particularly, the important progress extracted from in situ and operando spectroscopy techniques provides insights into how local reaction environment affects C-C coupling and key intermediates formation that lead to reaction pathways toward a desired C2+ product. The possible future direction in understanding and engineering the local reaction environment is also provided.

20.
Angew Chem Int Ed Engl ; : e202403229, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38577991

RESUMO

We present a catalyst-free route for the reduction of carbon dioxide integrated with the formation of a carbon-carbon bond at the air/water interface of negatively charged aqueous microdroplets, at ambient temperature. The reactions proceed through carbanion generation at the α-carbon of a ketone followed by nucleophilic addition to CO2. Online mass spectrometry reveals that the product is an α-ketoacid. Several factors, such as the concentration of the reagents, pressure of CO2 gas, and distance traveled by the droplets, control the kinetics of the reaction. Theoretical calculations suggest that water in the microdroplets facilitates this unusual chemistry. Furthermore, such a microdroplet strategy has been extended to seven different ketones. This work demonstrates a green pathway for the reduction of CO2 to useful carboxylated organic products.

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