-
Conrad Ross posted an update 7 hours, 46 minutes ago
A flow-controlled microfluidic device for parallel and combinatorial screening of crystalline materials can profoundly impact the discovery and development of active pharmaceutical ingredients and other crystalline materials. While the existing continuous-flow microfluidic devices allow crystals to nucleate under controlled conditions in the channels, their growth consumes solute from the solution leading to variation in the downstream composition. The materials screened under such varying conditions are less reproducible in large-scale synthesis. GSK-4362676 chemical structure There exists no continuous-flow microfluidic device that traps and grows crystals under controlled conditions for parallel screening. Here we show a blueprint of such a microfluidic device that has parallel-connected micromixers to trap and grow crystals under multiple conditions simultaneously. The efficacy of a multi-well microfluidic device is demonstrated to screen polymorphs, morphology, and growth rates of l-histidine via antisolvent crystallization at eight different solution conditions, including variation in molar concentration, vol% of ethanol, and supersaturation. The overall screening time for l-histidine using the multi-well microfluidic device is ∼30 min, which is at least eight times shorter than the sequential screening process. The screening results are also compared with the conventional 96-well microtiter device, which significantly overestimates the fraction of stable form as compared to metastable form and shows high uncertainty in measuring growth rates. The multi-well microfluidic device paves the way for next-generation microfluidic devices that are amenable to automation for high-throughput screening of crystalline materials.Dysfunction of the intestinal epithelial barrier and intestinal microbiota dysbiosis can drive the onset or aggravation of ulcerative colitis (UC). Bilobalide (BI) is an extract of Ginkgo biloba that has been shown to exhibit a range of anti-inflammatory properties. Herein, we explored functional and mechanistic effects of BI treatment in a rodent model of DSS-induced UC. These analyses revealed that BI treatment was sufficient to reduce disease severity, increase colon length, and normalize colon histological characteristics relative to those observed in DSS-treated model mice. BI also enhanced the expression of tight junction proteins associated with intestinal barrier integrity including ZO-1, Occludin, and Claudin-3. Through 16S rDNA sequencing analyses, BI was also found to influence the overall richness of the intestinal microbiome, promoting the proliferation of probiotic species including Lactobacillus. Consistent with these in vivo findings, BI treatment protected RAW264.7 cells against lipopolysaccharide (LPS)-induced inflammatory damage, suppressing the activation of the AKT/NF-κB p65 and MAPK signaling pathways in this experimental context. In summary, these findings revealed that BI can suppress MAPK and AKT/NF-κB p65 signaling, thereby suppressing the production of inflammatory cytokines including IL-1β, IL-6, and TNF-α, while additionally alleviating UC severity by facilitating repair of the intestinal epithelial barrier and the remodeling of intestinal microbial communities.Semiconductor photocatalysts are widely used in environmental remediation and energy conversion processes that affect social development. These processes involve, for example, hydrogen production from water splitting, carbon dioxide reduction, pollutant degradation, and the conversion of raw organic chemical materials into high-value-added chemicals. Metal halide perovskites (MHPs) have become a new class of promising cheap and easy to manufacture candidate materials for use in photocatalytic semiconductors due to their advantages of high extinction coefficients, optimal band gaps, high photoluminescence quantum yields, and long electron-hole diffusion lengths. However, their unstable ion-bonded crystal structures (very low theoretical decomposition energy barriers) limit their widespread application. In this review, we introduce the physical properties of MHP materials suitable for photocatalysis, and MHP-based photocatalytic particle suspension systems, photoelectrode thin film systems, and photovoltaic-photo(electro)chemical systems. Then, numerous studies realizing efficient and stable photocatalytic water splitting, carbon dioxide reduction, organic conversion, and other reactions involving MHP materials were highlighted. In addition, we conducted rigorous analysis of the potential problems that could hinder progress in this new scientific research field, such as Pb element toxicity and material instability. Finally, we outline the potential opportunities and directions for photocatalysis research based on MHPs.Instability problems encountered by Ag nanocrystals largely limit their use in practical applications. In AuAg bimetallic alloys, the stability of Ag can be greatly enhanced, whereas doping a high fraction of Au to the alloy usually leads to the loss of the superior properties of Ag and undesirable degradation of the quality factor of the plasmonic resonance. Herein, we provide experimental evidence that the atomically homogenous AuAg alloy nanocrystals with Au fraction as low as 4.9% (at%) possess comparable stability to pure Au, while the superior plasmonic properties of Ag are largely reserved. The study is based on the synthetic strategy developed for the overgrowth on the Au nanorods of atomically homogenous AuAg alloy shells with a tunable Au/Ag ratio but constant size and anisotropic shape. The stability of over 800 individual alloy nanocrystals in the absence of surfactants is simultaneously characterized at the single-particle level for over 10 h under light irradiation. The stability transition is explained in correlation with the charge redistribution of Ag occurring at the same critical Au fraction. We note that such bimetallic alloy nanocrystals with a low Au fraction possessing both high stability and high quality of resonance are preferred in fundamental researches and practical applications.
Intraoperative fluoroscopy facilitates minimally invasive surgery, and although it is irreplaceable in terms of intraoperative guidance, it results in substantial radiation exposure to the patient and surgical team. Although the risk of radiation exposure because of equipment factors has been described, there is little known about the impact of surgeon experience on radiation exposure. The aim of this study was to determine whether there is a relationship between years of surgical experience and total dose of radiation used for an archetypal pediatric orthopaedic surgical procedure that requires intraoperative fluoroscopy.
This was a retrospective cohort study of children undergoing closed reduction and percutaneous pinning for supracondylar humerus fractures at a level I pediatric trauma center. Information pertaining to radiation dosage was gathered including fluoroscopic time, total images acquired, magnification use, and dose area product (DAP). Regression analysis was used to evaluate the effect of surgeon experience on the outcome variables.