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1.
Hepatology ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38954829

RESUMO

Hospitalized patients with cirrhosis frequently require critical care management for sepsis, hepatic encephalopathy, respiratory failure, acute variceal bleeding, acute kidney injury (AKI), shock and optimization for liver transplantation (LT), while outpatients have unique care considerations. Point-of-care ultrasonography (POCUS) enhances bedside examination of the hepatobiliary system and relevant extrahepatic sites. POCUS includes cardiac ultrasound and is used to assess volume status and hemodynamic parameters like cardiac output, systemic vascular resistance, cardiac contractility, and pulmonary artery pressure, which aid in the early and accurate diagnosis of heart failure, cirrhotic cardiomyopathy, porto-pulmonary hypertension, hepatopulmonary syndrome, arrhythmia, and pulmonary embolism. This also helps in fluid management and vasopressor use in resuscitation of patients with cirrhosis. Lung ultrasound can help in differentiating pneumonia, effusion, and edema. Further, ultrasonography guides interventions such as line placement, drainage of abdominal collections/abscesses, relief of tension pneumothorax, drainage of pleural and pericardial effusions, and biliary drainage in cholangitis. Additionally, its role is essential to assess liver masses, foci of sepsis, for appropriate sites for paracentesis, and to assess for vascular disorders such as portal vein or hepatic vein thrombosis. Renal ultrasound can identify renal and post-renal causes of AKI and aid in diagnosis of pre-renal AKI through volume assessment. In this review, we address the principles and methods of POCUS in hospitalized patients and in outpatients with cirrhosis and discuss the application of this diverse modality in clinical hepatology.

2.
J Environ Manage ; 366: 121656, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38981276

RESUMO

The accumulation of soil legacy phosphorus (P) due to past fertilization practices poses a persistent challenge for agroecosystem management and water quality conservation. This study investigates the spatial distribution and risk assessment of soil legacy P in subtropical grasslands managed for cow-calf operations in Florida, with two pasture types along the intensity gradient: improved vs semi-native pastures. Soil samples from 1438 locations revealed substantial spatial variation in soil legacy P, with total P concentrations ranging from 11.46 to 619.54 mg/kg and Mehlich-1 P concentrations spanning 0.2-187.27 mg/kg. Our analyses revealed that most of the sites in semi-native pastures may function as P sinks by exhibiting positive Soil P Storage Capacity (SPSC) values, despite having high levels of soil total P. These locales of higher SPSC values were associated with high levels of aluminum, iron, and organic matter that can adsorb P. In addition, our results from spatial random forest modelling demonstrated that factors including elevation, soil organic matter, available water storage, pasture type, soil pH, and soil order are important to explain and predict spatial variations in SPSC. Incorporating SPSC into the Phosphorus Index (PI) spatial assessment, we further determined that only 3% of the study area was considered as high or very high PI categories indicative of a significant risk for P loss. Our evaluation of SPSC and PI underscores the complexity inherent in P dynamics, emphasizing the need for a holistic approach to assessing P loss risk. Insights from this work not only help optimize agronomic practices but also promote sustainable land management, thus ensuring the long-term health and sustainability of grass-dominated agroecosystems.

3.
Ecol Appl ; : e3007, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982756

RESUMO

Humans have profoundly altered phosphorus (P) cycling across scales. Agriculturally driven changes (e.g., excessive P-fertilization and manure addition), in particular, have resulted in pronounced P accumulations in soils, often known as "soil legacy P." These legacy P reserves serve as persistent and long-term nonpoint sources, inducing downstream eutrophication and ecosystem services degradation. While there is considerable scientific and policy interest in legacy P, its fine-scale spatial heterogeneity, underlying drivers, and scales of variance remain unclear. Here we present an extensive field sampling (150-m interval grid) and analysis of 1438 surface soils (0-15 cm) in 2020 for two typical subtropical grassland types managed for livestock production: Intensively managed (IM) and Semi-natural (SN) pastures. We ask the following questions: (1) What is the spatial variability, and are there hotspots of soil legacy P? (2) Does soil legacy P vary primarily within pastures, among pastures, or between pasture types? (3) How does soil legacy P relate to pasture management intensity, soil and geographic characteristics? and (4) What is the relationship between soil legacy P and aboveground plant tissue P concentration? Our results showed that three measurements of soil legacy P (total P, Mehlich-1, and Mehlich-3 extractable P representing labile P pools) varied substantially across the landscape. Spatial autoregressive models revealed that soil organic matter, pH, available Fe and Al, elevation, and pasture management intensity were crucial predictors for spatial patterns of soil P, although models were more reliable for predicting total P (68.9%) than labile P. Our analysis further demonstrated that total variance in soil legacy P was greater in IM than SN pastures, and intensified pasture management rescaled spatial patterns of soil legacy P. In particular, after controlling for sample size, soil P was extremely variable at small scales, with variance diminished as spatial scale increased. Our results suggest that broad pasture- or farm-level best management practices may be limited and less efficient, especially for more IM pastures. Rather, management to curtail soil legacy P and mitigate P loading and losses should be implemented at fine scales designed to target spatially distinct P hotspots across the landscape.

4.
5.
J Conserv Dent Endod ; 27(5): 529-534, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38939536

RESUMO

Aim: This study aims to evaluate the microleakage between the gingival seat and base material and to assess the interface integrity between the base material and overlying composite in class II cavities restored using deep margin elevation. Materials and Methods: Thirty maxillary molars (n = 30) were taken, and class II cavities were prepared with a gingival seat extending below the cementoenamel junction. These teeth were divided into three groups for subgingival margin elevation using different materials: Group A (n = 10) - flowable composite, Group B (n = 10) - glass ionomer cement (GIC), and Group C (n = 10) - GIC with nanohydroxyapatite (GIC n-HAp). The remaining cavities were restored with bulk-fill composite. After undergoing 1000 thermocycling cycles, half of the samples were examined for microleakage using confocal laser microscopy, and the other half were assessed for interface integrity using scanning electron microscopy. Microleakage was statistically analyzed by one-way ANOVA, and interface integrity was analyzed by Kruskal-Wallis tests. Results: The study found that GIC n-HAp exhibited significantly lower microleakage between the base material and gingival seat than flowable composite and GIC. However, regarding interface integrity between the base material and bulk-fill composite, flowable composite, and GIC outperformed GIC n-HAp. Conclusions: Incorporating n-HAp into GIC effectively reduced microleakage at the dentin-base material interface. However, the interface integrity between GIC n-HAp and the composite poses a challenge.

6.
Small ; : e2401594, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38860544

RESUMO

Defect engineering of metal-organic frameworks (MOFs) is a promising strategy for tailoring the interfacial characteristics between MOFs and polymers, aiming to create high-performance mixed matrix membranes (MMMs). This study introduces a new approach using dual defective alkylamine (AA)-modulated zeolitic imidazolate framework-8 (DAZIF-8), to develop high-flux MMMs. Tributylamine (TBA) and triethylamine (TEA) monodentate ligands coordinate with zinc ions in varying compositions. A mixture of Zn(CH3COO)2·2H2O:2-methylimidazole (Mim):AA in a 1:1.75:5 molar ratio facilitates high-yield coordination between Zn and multiple organic ligands, including Zn-Mim, Zn-TEA, and Zn-TBA (>80%). Remarkably, DAZIF-8 containing 3 mol% TBA and 2 mol% TEA exhibits exceptional characteristics, such as a Brunauer-Emmett-Teller surface area of 1745 m2 g-1 and enhanced framework rigidity. Furthermore, dual Zn-AA coordination sites on the framework's outer surface enhance compatibility with the polyimide (PI) matrix through electron donor-acceptor interactions, enabling the fabrication of high-loading MMMs with excellent mechanical durability. Importantly, the PI/DAZIF-8 (60/40 w/w) MMM demonstrates an unprecedented 759% enhancement in ethylene (C2H4) permeability (281 Barrer) with a moderate ethylene/ethane (C2H4/C2H6) selectivity of 2.95 compared to the PI, surpassing the polymeric upper limit for C2H4/C2H6 separation.

7.
Front Hum Neurosci ; 18: 1405586, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38919881

RESUMO

Introduction: Brain cancer is a frequently occurring disease around the globe and mostly developed due to the presence of tumors in/around the brain. Generally, the prevalence and incidence of brain cancer are much lower than that of other cancer types (breast, skin, lung, etc.). However, brain cancers are associated with high mortality rates, especially in adults, due to the false identification of tumor types, and delay in the diagnosis. Therefore, the minimization of false detection of brain tumor types and early diagnosis plays a crucial role in the improvement of patient survival rate. To achieve this, many researchers have recently developed deep learning (DL)-based approaches since they showed a remarkable performance, particularly in the classification task. Methods: This article proposes a novel DL architecture named BrainCDNet. This model was made by concatenating the pooling layers and dealing with the overfitting issues by initializing the weights into layers using 'He Normal' initialization along with the batch norm and global average pooling (GAP). Initially, we sharpen the input images using a Nimble filter, which results in maintaining the edges and fine details. After that, we employed the suggested BrainCDNet for the extraction of relevant features and classification. In this work, two different forms of magnetic resonance imaging (MRI) databases such as binary (healthy vs. pathological) and multiclass (glioma vs. meningioma vs. pituitary) are utilized to perform all these experiments. Results and discussion: Empirical evidence suggests that the presented model attained a significant accuracy on both datasets compared to the state-of-the-art approaches, with 99.45% (binary) and 96.78% (multiclass), respectively. Hence, the proposed model can be used as a decision-supportive tool for radiologists during the diagnosis of brain cancer patients.

9.
Artif Cells Nanomed Biotechnol ; 52(1): 238-249, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38696111

RESUMO

Malaria is a mosquito-borne infectious disease that is caused by the Plasmodium parasite. Most of the available medication are losing their efficacy. Therefore, it is crucial to create fresh leads to combat malaria. Green silver nanoparticles (AgNPs) have recently attracted a lot of attention in biomedical research. As a result, green mediated AgNPs from leaves of Terminalia bellirica, a medicinal plant with purported antimalarial effects, were used in this investigation. Initially, cysteine-rich proteins from Plasmodium species were studied in silico as potential therapeutic targets. With docking scores between -9.93 and -11.25 kcal/mol, four leaf constituents of Terminalia bellirica were identified. The green mediated silver nanoparticles were afterward produced using leaf extract and were further examined using UV-vis spectrophotometer, DLS, Zeta potential, FTIR, XRD, and FESEM. The size of synthesized TBL-AgNPs was validated by the FESEM results; the average size of TBL-AgNPs was around 44.05 nm. The zeta potential study also supported green mediated AgNPs stability. Additionally, Plasmodium falciparum (3D7) cultures were used to assess the antimalarial efficacy, and green mediated AgNPs could effectively inhibit the parasitized red blood cells (pRBCs). In conclusion, this novel class of AgNPs may be used as a potential therapeutic replacement for the treatment of malaria.


Assuntos
Antimaláricos , Química Verde , Nanopartículas Metálicas , Extratos Vegetais , Folhas de Planta , Plasmodium falciparum , Prata , Terminalia , Prata/química , Prata/farmacologia , Antimaláricos/química , Antimaláricos/farmacologia , Antimaláricos/síntese química , Nanopartículas Metálicas/química , Terminalia/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Plasmodium falciparum/efeitos dos fármacos , Simulação de Acoplamento Molecular , Humanos
10.
J Phys Chem B ; 128(21): 5218-5227, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38756068

RESUMO

Over the past decade, multilayered graphene oxide (GO) membranes have emerged as promising candidates for desalination applications. Despite their potential, a comprehensive understanding of separation mechanisms remains elusive due to the intricate morphology and structural arrangement of interlayer galleries. Moreover, a critical concern of multilayered GO membranes is their susceptibility to swelling within aqueous environments, which hinders their practical implementation. Therefore, this study introduces cation intercalation within GO laminates to elucidate the underlying factors governing swelling behavior and subsequently mitigate it. Moreover, this study performed nonequilibrium molecular dynamics simulations on the cation (Mg2+ or K+)-intercalated lamellar and nonlamellar GO membranes to understand the effect of the arrangement of GO sheets on the retention time of intercalated cations within GO layers, water permeance, and salt rejection mechanism in the reverse osmosis process using cation-intercalated GO membranes. Our results highlight that lamellar GO membranes exhibit higher water permeance, attributed to their well-defined interlayer gallery structure. On the other hand, nonlamellar GO membranes display superior salt rejection due to their complex interlayer gallery structure that impedes salt permeation. Moreover, the structural complexity of nonlamellar GO membranes contributes to greater stability by retention of the more intercalated cations for a longer time within the layers. Furthermore, it is observed that a higher percentage of Mg2+ cations remained inside the GO laminates as compared to K+ cations, hence resulting in the greater stability of the Mg2+-intercalated GO membrane in the aqueous environment.

11.
Sci Rep ; 14(1): 11743, 2024 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-38778072

RESUMO

Agricultural field experiments are costly and time-consuming, and often struggling to capture spatial and temporal variability. Mechanistic crop growth models offer a solution to understand intricate crop-soil-weather system, aiding farm-level management decisions throughout the growing season. The objective of this study was to calibrate and the Crop Environment Resource Synthesis CERES-Maize (DSSAT v 4.8) model to simulate crop growth, yield, and nitrogen dynamics in a long-term conservation agriculture (CA) based maize system. The model was also used to investigate the relationship between, temperature, nitrate and ammoniacal concentration in soil, and nitrogen uptake by the crop. Additionally, the study explored the impact of contrasting tillage practices and fertilizer nitrogen management options on maize yields. Using field data from 2019 and 2020, the DSSAT-CERES-Maize model was calibrated for plant growth stages, leaf area index-LAI, biomass, and yield. Data from 2021 were used to evaluate the model's performance. The treatments consisted of four nitrogen management options, viz., N0 (without nitrogen), N150 (150 kg N/ha through urea), GS (Green seeker-based urea application) and USG (urea super granules @150kg N/ha) in two contrasting tillage systems, i.e., CA-based zero tillage-ZT and conventional tillage-CT. The model accurately simulated maize cultivar's anthesis and physiological maturity, with observed value falling within 5% of the model's predictions range. LAI predictions by the model aligned well with measured values (RMSE 0.57 and nRMSE 10.33%), with a 14.6% prediction error at 60 days. The simulated grain yields generally matched with measured values (with prediction error ranging from 0 to 3%), except for plots without nitrogen application, where the model overestimated yields by 9-16%. The study also demonstrated the model's ability to accurately capture soil nitrate-N levels (RMSE 12.63 kg/ha and nRMSE 12.84%). The study concludes that the DSSAT-CERES-Maize model accurately assessed the impacts of tillage and nitrogen management practices on maize crop's growth, yield, and soil nitrogen dynamics. By providing reliable simulations during the growing season, this modelling approach can facilitate better planning and more efficient resource management. Future research should focus on expanding the model's capabilities and improving its predictions further.


Assuntos
Agricultura , Fertilizantes , Nitrogênio , Solo , Zea mays , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Nitrogênio/metabolismo , Agricultura/métodos , Solo/química , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Produtos Agrícolas/crescimento & desenvolvimento , Biomassa
12.
Heliyon ; 10(10): e30669, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38770320

RESUMO

Voltage and reactive power regulation in a deregulated microgrid can be achieved by strategically placing the Static Synchronous Compensator (STATCOM) in coordination with other renewable energy sources, thus ensuring high-end stability and independent control. STATCOM plays a crucial role in effectively addressing power quality issues such as voltage fluctuation and reactive power imbalances caused by the intermittent nature of wind energy conversion systems. To successfully integrate STATCOM into the existing system, it is essential that the control system employed for STATCOM coordination aligns with the Doubly-Fed Induction Generator (DFIG) controller within the microgrid. Therefore, an efficient control algorithm is required in the microgrid, capable of coordinating with the DFIG controller while maintaining system stability. The utilization of a Genetic Algorithm (GA) in calibrating the Restricted Boltzmannn Machine (RBM) can streamline the process of determining optimal hyperparameters for specific tasks, eliminating the need for computationally intensive and time-consuming grid searches or manual tuning. This approach is particularly advantageous when dealing with large datasets within short time durations. In this research, a Simulink model comprising a DFIG-based microgrid and STATCOM has been developed to demonstrate the effectiveness of the proposed control system using RBM in managing STATCOM and facilitating microgrid operations.

13.
Clin Ter ; 175(3): 181-183, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38767076

RESUMO

Abstract: COVID-19 pandemic has increased the amount of plastic burden to environment and complexities of plastic waste management. Change in behavioral pattern with advent of this pandemic led to increased practice of hygiene and increased use of different types of personal protective equipment. Unfortunately, rapid rise in production of the PPEs (like Hazmat suit, gloves, etc.) and single-use plastics used in RT-PCR and other testing are the biggest source for increased non-biodegradable plastic waste leading to amplified burden on plastic waste management. A number of measures like prioritizing the policies directed towards changes at behavioral, social and institutional level need to be started. Also, reduction in plastic waste along with proper plastic waste management policies should be implemented. To prevent the transition from one pandemic to other; improvement in government policies with public private partnership are the need of the hour.


Assuntos
COVID-19 , Saúde Global , Plásticos , COVID-19/prevenção & controle , COVID-19/epidemiologia , Humanos , Pandemias , Equipamento de Proteção Individual/provisão & distribuição , Gerenciamento de Resíduos/métodos
14.
Liver Transpl ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38771635

RESUMO

Hepatorenal syndrome-acute kidney injury (HRS-AKI) is associated with significant morbidity and mortality. While liver transplantation is the definitive treatment, continuous terlipressin infusion for HRS-AKI may provide benefit and, as such, was assessed in a population composed of candidates for liver transplant (LT). Fifty hospitalized LT-eligible patients with HRS-AKI received a single bolus followed by continuous terlipressin infusion. Acute-on-chronic liver failure grade 3, serum creatinine (SCr)>5.0 mg/dL, or Model for End-Stage Liver Disease (MELD) ≥35 were exclusions. Fifty hospitalized patients who received midodrine and octreotide or norepinephrine for HRS-AKI served as a historical comparator cohort. Complete response (CR) was defined as a ≥30% decrease in SCr with end-of-treatment (EOT) SCr≤1.5, partial response as a ≥30% decrease in SCr with EOT SCr>1.5, and nonresponse as a <30% decrease in SCr. CR rate was significantly higher in the terlipressin cohort compared to the historical cohort (64% vs. 16%, p <0.001). Survival, while numerically higher in those who received terlipressin, was statistically similar (D30: 94% vs. 82%, p =0.12; D90: 78% vs. 68%, p =0.37). Renal replacement therapy (RRT) was more common among terlipressin NR than CR and PR (70% vs. 3% vs. 13%, p < 0.001). EOT MELD and SCr were significantly lower within terlipressin cohort (MELD: 19 vs. 25, SCr: 1.4 vs. 2.1 mg/dL, p <0.001). Sixteen of 40 terlipressin-treated patients received LT-alone (terlipressin CR in 10/16). One patient on terlipressin had a hypoxic respiratory failure that responded to diuretics; one possibly had drug-related rash. With continuous terlipressin infusion, a CR rate of 64% was observed with a favorable safety profile. Terlipressin use was associated with lower EOT MELD and SCr than the historical midodrine and octreotide/norepinephrine cohort; LT-alone was accomplished in a high proportion of complete terlipressin responders.

15.
Lancet Gastroenterol Hepatol ; 9(8): 745-757, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38754453

RESUMO

Cirrhosis is an immune dysfunction state, and as such, patients with cirrhosis are susceptible to bacterial, fungal, and viral infections. Because of infection, these patients have a propensity to develop multiorgan failure, which is associated with high mortality. Bacterial infections are the most prevalent type of infection in patients with cirrhosis, with the prevalence of bacterial infections in patients admitted for an acute decompensating event ranging from 24% to 29%. Together with invasive fungal infections, bacterial infections are the most severe. Multidrug-resistant organisms have been evolving at a rapid and alarming rate around the world, which presents enormous challenges. The development of effective measures for the prevention, early detection, and treatment of infections in patients with cirrhosis is challenging, given the rising incidence of infections in this patient population.


Assuntos
Cirrose Hepática , Humanos , Cirrose Hepática/complicações , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/complicações , Infecções Bacterianas/tratamento farmacológico , Micoses/epidemiologia
16.
Aliment Pharmacol Ther ; 59(12): 1489-1509, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38693712

RESUMO

BACKGROUND: The increase in prevalence of liver disease globally will lead to a substantial incremental burden on intensive care requirements. While liver transplantation offers a potential life-saving intervention, not all patients are eligible due to limitations such as organ availability, resource constraints, ongoing sepsis or multiple organ failures. Consequently, the focus of critical care of patients with advanced and decompensated cirrhosis turns to liver-centric intensive care protocols, to mitigate the high mortality in such patients. AIM: Provide an updated and comprehensive understanding of cirrhosis management in critical care, and which includes emergency care, secondary organ failure management (mechanical ventilation, renal replacement therapy, haemodynamic support and intensive care nutrition), use of innovative liver support systems, infection control, liver transplantation and palliative and end-of life care. METHODS: We conducted a structured bibliographic search on PubMed, sourcing articles published up to 31 March 2024, to cover topics addressed. We considered data from observational studies, recommendations of society guidelines, systematic reviews, and meta-analyses, randomised controlled trials, and incorporated our clinical expertise in liver critical care. RESULTS: Critical care management of the patient with cirrhosis has evolved over time while mortality remains high despite aggressive management with liver transplantation serving as a crucial but not universally available resource. CONCLUSIONS: Implementation of organ support therapies, intensive care protocols, nutrition, palliative care and end-of-life discussions and decisions are an integral part of critical care of the patient with cirrhosis. A multi-disciplinary approach towards critical care management is likely to yield better outcomes.


Assuntos
Cuidados Críticos , Estado Terminal , Cirrose Hepática , Transplante de Fígado , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Estado Terminal/terapia , Cuidados Críticos/métodos , Cuidados Paliativos/métodos , Assistência Terminal/métodos
19.
Health Promot Perspect ; 14(1): 9-18, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38623344

RESUMO

Background: The World Health Assembly (WHA), on 1st December 2021, unanimously agreed to launch a global process to draft and negotiate a convention, agreement, or other international instrument under the World Health Organization's (WHO's) constitution to strengthen pandemic prevention, preparedness, and response. We aimed to explore the role of global health diplomacy (GHD) in pandemic treaty negotiations by providing deep insight into the ongoing drafting process under the WHO leadership. Methods: We conducted a narrative review by searching Scopus, Web of Sciences, PubMed, MEDLINE, and Google Scholar search engine using the keywords "Pandemic Treaty," OR "International Health Regulations," OR "International conventions," OR "International treaties" in the context of recent COVID-19 pandemic. Besides, we included articles recommending the need for GHD, leadership and governance mechanisms for this international treaty drafting approved by the WHA. Results: Amid the COVID-19 pandemic, the concept of GHD bolstered the international system and remained high on the agendas of many national, regional and global platforms. As per Article 19 of the WHO constitution, the Assembly established an intergovernmental negotiating body (INB) to draft and negotiate this convention/ agreement to protect the world from disease outbreaks of pandemic potential. Since GHD has helped to strengthen international cooperation in health systems and address inequities in achieving health-related global targets, there is a great scope for the successful drafting of this pandemic treaty. Conclusion: The pandemic treaty is a defining moment in global health governance, particularly the pandemic governance reforms. However, the treaty's purpose will only be served if the equity considerations are optimized, accountability mechanisms are established, and a sense of shared responsibility is embraced. While fulfilling treaty commitments might be complex and challenging, it provides an opportunity to rethink and build resilient systems for pandemic preparedness and response in the future.

20.
Angew Chem Int Ed Engl ; 63(27): e202403229, 2024 Jul 01.
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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