-
Marine Drugs May 2024Transition metal catalysis has contributed to the discovery of novel methodologies and the preparation of natural products, as well as new chances to increase the... (Review)
Review
Transition metal catalysis has contributed to the discovery of novel methodologies and the preparation of natural products, as well as new chances to increase the chemical space in drug discovery programs. In the case of marine drugs, this strategy has been used to achieve selective, sustainable and efficient transformations, which cannot be obtained otherwise. In this perspective, we aim to showcase how a variety of transition metals have provided fruitful couplings in a wide variety of marine drug-like scaffolds over the past few years, by accelerating the production of these valuable molecules.
Topics: Catalysis; Biological Products; Transition Elements; Aquatic Organisms; Drug Discovery; Animals
PubMed: 38921564
DOI: 10.3390/md22060253 -
Biomimetics (Basel, Switzerland) Jun 2024Public transportation scheduling aims to optimize the allocation of resources, enhance efficiency, and increase passenger satisfaction, all of which are crucial for...
Public transportation scheduling aims to optimize the allocation of resources, enhance efficiency, and increase passenger satisfaction, all of which are crucial for building a sustainable urban transportation system. As a complement to public transportation, bike-sharing systems provide users with a solution for the last mile of travel, compensating for the lack of flexibility in public transportation and helping to improve its utilization rate. Due to the characteristics of shared bikes, including peak usage periods in the morning and evening and significant demand fluctuations across different areas, optimizing shared bike dispatch can better meet user needs, reduce vehicle vacancy rates, and increase operating revenue. To address this issue, this article proposes a comprehensive decision-making approach for spatiotemporal demand prediction and bike dispatch optimization. For demand prediction, we design a T-GCN (Temporal Graph Convolutional Network)-based bike demand prediction model. In terms of dispatch optimization, we consider factors such as dispatch capacity, distance restrictions, and dispatch costs, and design an optimization solution based on genetic algorithms. Finally, we validate the approach using shared bike operating data and show that the T-GCN can effectively predict the short-term demand for shared bikes. Meanwhile, the optimization model based on genetic algorithms provides a complete dispatch solution, verifying the model's effectiveness. The shared bike dispatch approach proposed in this paper combines demand prediction with resource scheduling. This scheme can also be extended to other transportation scheduling problems with uncertain demand, such as store replenishment delivery and intercity inventory dispatch.
PubMed: 38921248
DOI: 10.3390/biomimetics9060368 -
Frontiers in Public Health 2024
Topics: Humans; Malaria; Global Health; Disease Eradication
PubMed: 38915746
DOI: 10.3389/fpubh.2024.1433213 -
Scientific Reports Jun 2024For alkaline anion-exchange membrane electrolysers and fuel cells to become a technological reality, hydroxide-ion (OH) conducting membranes that are flexible, robust,...
For alkaline anion-exchange membrane electrolysers and fuel cells to become a technological reality, hydroxide-ion (OH) conducting membranes that are flexible, robust, affording high OH conductivity, and synthesised in a low-cost and scalable way must be developed. In this paper, we engineer a stable, self-supporting, and flexible fibre mat using a low-cost ZIF-8 metal-organic framework composited with ionic liquid tetrabutylammonium hydroxide and widely used polyacrylonitrile as polymeric backbone. We obtain mats with a high intrinsic OH conductivity for a metal-organic framework-based material already at room temperature, without added ion-conductor polymers. This approach will contribute to the development of low-cost and tuneable ion-conducting membranes.
PubMed: 38914565
DOI: 10.1038/s41598-024-64646-9 -
ACS Energy Letters Jun 2024Strain is an important property in halide perovskite semiconductors used for optoelectronic applications because of its ability to influence device efficiency and...
Strain is an important property in halide perovskite semiconductors used for optoelectronic applications because of its ability to influence device efficiency and stability. However, descriptions of strain in these materials are generally limited to bulk averages of bare films, which miss important property-determining heterogeneities that occur on the nanoscale and at interfaces in multilayer device stacks. Here, we present three-dimensional nanoscale strain mapping using Bragg coherent diffraction imaging of individual grains in CsFAPb(IBr) and CsFASnI (FA = formamidinium) halide perovskite absorbers buried in full solar cell devices. We discover large local strains and striking intragrain and grain-to-grain strain heterogeneity, identifying distinct islands of tensile and compressive strain inside grains. Additionally, we directly image dislocations with surprising regularity in CsFASnI grains and find evidence for dislocation-induced antiphase boundary formation. Our results shine a rare light on the nanoscale strains in these materials in their technologically relevant device setting.
PubMed: 38911532
DOI: 10.1021/acsenergylett.4c00921 -
Dental Materials : Official Publication... Jun 2024The permeability of triamcinolone acetonide (TA), from bilayer mucoadhesive buccal films, through a biomimetic membrane, Permeapad™, was investigated employing Franz...
OBJECTIVES
The permeability of triamcinolone acetonide (TA), from bilayer mucoadhesive buccal films, through a biomimetic membrane, Permeapad™, was investigated employing Franz diffusion cell. The delivery systems composition and ethyl cellulose (EC) backing layer, on drug permeability, were assessed.
METHODS
Three TA-loaded films were tested; hydroxypropyl methylcellulose (HPMC K4M; bilayer [F1] and monolayer), HPMC K4M/Polyvinylpyrrolidone (PVP): 90/10 [F2], and HPMC K15M film [F3]. All films contained propylene glycol (PG-plasticiser). TA solution alone was used as a control. TA permeability via a Permeapad™ barrier, simulating buccal mucosa, was assessed over 8 h using a Franz diffusion cell. TA permeated into the receptor compartment, released in the donor compartment, and located on/within the Permeapad™ barrier were analysed using UV-spectrophotometer.
RESULTS
45.7 % drug retention within the Permeapad™ barrier was delivered from F1 (highest). F1, F2, and F3 significantly improved the TA's permeability through Permeapad™, compared to TA solution alone (e.g., 8.5 % TA-solution, 21.5 %-F1), attributed to the synergy effect of HPMC and propylene glycol acting as penetration enhancers. F1 displayed a significant increase in drug permeability (receptor compartment; 21.5 %) compared to F3 (17.0 %). PVP significantly enhanced drug permeability (27.5 %). Impermeable EC backing layer controlled unidirectional drug release and reduced drug loss into the donor compartment (e.g., ∼28 % for monolayer film to ∼10 % for bilayer film, F1).
SIGNIFICANCE
The mucoadhesive films demonstrated improved TA permeability via Permeapad™. The findings suggest that these bilayer mucoadhesive films, particularly F1, hold promise for the effective topical treatment of oral mucosa disorders, such as recurrent aphthous stomatitis and oral lichen planus.
PubMed: 38902145
DOI: 10.1016/j.dental.2024.06.016 -
The Science of the Total Environment Jun 2024Previous investigations have reported that individuals living in greener neighborhoods have better cardiovascular health. It is unclear whether the effects reported at...
INTRODUCTION
Previous investigations have reported that individuals living in greener neighborhoods have better cardiovascular health. It is unclear whether the effects reported at large geographic scales persist when examined at an intra-neighborhood level. The effects of greenness have not been thoroughly examined using high-resolution metrics of greenness exposure, and how they vary with spatial scales of assessment or participant characteristics.
METHODS
We conducted a cross-sectional assessment of associations between blood pressure and multiple high-resolution measures of residential area greenness in spatially concentrated HEAL Study cohort of the Green Heart Project. We employed generalized linear models, accounting for individual-level covariates, to examine associations between different high-resolution measures of greenness and blood pressure among 667 participants in a 4 sq. mile contiguous neighborhood area in Louisville, KY.
RESULTS
In adjusted models, we observed significant inverse associations between residential greenness, measured by leaf area index (LAI), and systolic blood pressure (SBP) within 150-250 m and 500 m of homes, but not for Normalized Difference Vegetation Index (NDVI) or grass cover. Weaker associations were also found with diastolic blood pressure (DBP). Significant positive associations were observed between LAI and SBP among participants who reported being female, White, without obesity, non-exercisers, non-smokers, younger age, of lower income, and who had high nearby roadway traffic. We found few significant associations between grass cover and SBP, but an inverse association in those with obesity, but positive associations for those without obesity.
CONCLUSIONS
We found that leaf surface area of trees around participants home is strongly associated with lower blood pressure, with little association with grass cover. These effects varied with participant characteristics and spatial scales. More research is needed to test causative links between greenspace types and cardiovascular health and to develop population-, typology-, and place-based evidence to inform greening interventions.
PubMed: 38901580
DOI: 10.1016/j.scitotenv.2024.173788 -
The Journal of Physical Chemistry. C,... Jun 2024Zeolites contain extraframework cations that are exchangeable under favorable aqueous conditions; this is the fundamental feature for their application in water...
Zeolites contain extraframework cations that are exchangeable under favorable aqueous conditions; this is the fundamental feature for their application in water purification and necessary to produce cation forms for other applications such as catalysis. Optimization of the process is common, but there is little fundamental understanding based on real-time experiments of the mechanism of exchange for most zeolites. The sodium and potassium forms of zeolite chabazite selectively uptake Cs by ion exchange, leading to its application in removing radioactive Cs from industrial nuclear waste streams, as well as from contaminated environments in the aftermath of the Fukushima and Three Mile Island accidents. In this study, synchrotron powder X-ray diffraction patterns have been collected on chabazite as it undergoes Cs-ion exchange. Applying Rietveld refinement to these patterns has revealed the time-resolved structural changes that occur in the zeolite as exchange progresses, charting the changes in the spatial distribution of the extraframework cations and water molecules in the structure during the reaction. Ultimately, a detailed mechanistic understanding of how this dynamic ion-exchange reaction occurs has been obtained.
PubMed: 38894753
DOI: 10.1021/acs.jpcc.4c02145 -
The Journal of Arthroplasty Jun 2024Periprosthetic joint infection (PJI) remains a major problem. The bactericidal efficacy of commercial irrigation solutions for the treatment of infection is not well...
BACKGROUND
Periprosthetic joint infection (PJI) remains a major problem. The bactericidal efficacy of commercial irrigation solutions for the treatment of infection is not well established in the presence of porous titanium (Ti) implants. This study compared the in vitro efficacy of five irrigation solutions on infected three-dimensional (3D)-printed porous Ti discs.
METHODS
Titanium discs (2 x 4 mm, 400, 700, and 1,000 μm) were infected with S. aureus (1x10 CFU/ml) and incubated for 3 hours or 3 days to create acute or chronic infection with biofilm. Discs were irrigated with saline, antibiotic, or antiseptic solutions, then repeatedly sonicated. Sonicates were cultured for bacterial quantification. Statistical analyses were performed using one-way analysis of variance (ANOVA), followed by Tukey-Kramer post hoc testing (P < 0.05 significance). Biofilms were visualized by scanning electron microscopy (SEM).
RESULTS
Saline irrigation was ineffective in both groups. In acute infections with 400 μm pores, differences were found with saline versus solution #3 (P = 0.015) and #4 (P = 0.015). Solution #4 had the lowest bacterial counts for all pore sizes. For biofilm, irrigation with saline, solutions #1, #2, and #3 inadequately cleared bacteria in all pore sizes. Lower remaining concentrations were observed in #4 with 400μm pores compared to saline (P = 0.06) and #2 (P = 0.039). The SEM showed a reduction of biofilm in samples washed with #4.
CONCLUSION
Irrigation of infected porous Ti discs with saline, solutions #1 and #2 failed to reduce the bacterial load. The 400 μm discs consistently had more bacteria despite irrigation, highlighting the difficulty of removing bacteria from small pores. Solutions #3 and #4 reduced bacteria acutely, but only #4 demonstrated efficacy in clearing biofilm compared to saline. These results should be considered when treating PJI in the presence of porous components and the potential presence of biofilm.
PubMed: 38889807
DOI: 10.1016/j.arth.2024.06.024 -
The American Journal of Tropical... Jun 2024India has targeted malaria elimination by 2030. The national malaria control program has positioned its strategies in this direction. Substantial support in the form of...
India has targeted malaria elimination by 2030. The national malaria control program has positioned its strategies in this direction. Substantial support in the form of dynamic research inputs leading to policy formulation and change is needed to steer the country towards malaria elimination. Indian Council of Medical Research (ICMR), India's nodal research body, has been generating evidence and helping to frame several policies ranging from malaria management to vector control operations. Since the country is preparing for malaria elimination, the connection between the programmatic needs and the research agenda needs further strengthening. Typically, the national malaria control program handles the implementation of programmatic activities, while the national research body, ICMR, conducts research studies to generate evidence. We propose a virtual integration of the activities conducted by these two entities to maximize the potential for translating research findings into programmatic policies. Joint monitoring of drug and insecticide resistance, codevelopment and utilization of more innovative surveillance systems, data-backed mitigation responses, and overcoming last-mile challenges are reasons for the virtual amalgamation of the two bodies. Timely translation of research outputs into policy, co-opting of workforce and material resources, joint capacity building, and synergistic advocacy are benefits of the proposed new alliance for more efficient operations. The close functioning will provide impetus to narrow down current gaps and disrupt traditional barriers, galvanizing the country toward malaria elimination.
PubMed: 38889711
DOI: 10.4269/ajtmh.24-0011