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This study investigates ceramic fused filament fabrication (CF3) 3D printing of alumina with an emphasis on the impact of particle morphology on feedstock preparation and printability. Spherical powder displayed superior flow with higher apparent density, tap density, and powder packing fraction compared to irregular powder. A 55 vol % powder loading was chosen to ensure good flowability during printing. Irregular powder-based feedstocks had 40X higher viscosity than spherical powder feedstocks at 400 s−1 shear rate, posing potential printing challenges. Slow printing speed maintained low feed-rates for consistent material flow. The debinding and sintering process produced macroscopically defect-free alumina components with relative densities above 89 % for both powder morphologies. The focus of the work is on comparing two different powder particle morphologies influencing feedstock behavior, printing fidelity, and sintered part properties.

Emerging evidence suggests a significant contribution of primary cilia to cell division and proliferation. MicroRNAs, especially miR-17, contribute to cell cycle regulation and proliferation. Recent investigations have highlighted the dysregulated expression of miR-17 in various malignancies, underlining its potential role in cancer. However, the correlation between primary cilia and miR-17 has yet to be fully elucidated. The present study examines the presence of miR-17 in primary cilia. The miR-17 expression is studied in selected ciliary protein knockdown cells. Using in situ hybridization (ISH), we identified the subcellular localization of miR-17 in both cilium and cell body. We confirmed the importance of miR-17, progesterone receptor membrane component-2 (PGRMC2), and monosialodihexosylganglioside (GM3S) in cilia formation, as shown by the significant reduction in cilia and cilia length in knockdown cells compared to control. We also demonstrated the involvement of PGRMC2, GM3S, polycystin-2 (PKD2), and miR-17 in cellular proliferation and cell growth. Our studies revealed a hyperproliferative effect in the knockdown cells compared to control cells, suggesting the regulatory roles of PGRMC2/GM3S/PKD2/miR-17 in promoting cell proliferation. Overall, our studies conclude that ciliary proteins are involved in cell division and proliferation. We further hypothesize that primary cilia can serve as compartments to store and control genetic materials, further implicating their complex involvement in cellular processes.

AbstractA simple yet effective way of modeling survival data with cure fraction is by considering Box-Cox transformation cure model (BCTM) that unifies mixture and promotion time cure models. In this article, we numerically study the statistical properties of the BCTM when applied to interval censored data. Time-to-events associated with susceptible subjects are modeled through proportional hazards structure that allows for non-homogeneity across subjects, where the baseline hazard function is estimated by distribution-free piecewise linear function with varied degrees of non-parametricity. Due to missing cured statuses for right censored subjects, maximum likelihood estimates of model parameters are obtained by developing an expectation-maximization (EM) algorithm. Under the EM framework, the conditional expectation of the complete data log-likelihood function is maximized by considering all parameters (including the Box-Cox transformation parameter α) simultaneously, in contrast to conventional profile-likelihood technique of estimating α. The robustness and accuracy of the model and estimation method are established through a detailed simulation study under various parameter settings, and an analysis of real-life data obtained from a smoking cessation study. [ABSTRACT FROM AUTHOR]

Investigating the influence of different cellular mechanical and physical properties on cells in vitro is important for assessing cellular activities like differentiation, proliferation, and migration. Evaluating the mechanical response of the cells lodged on a scaffold due to variations in substrate roughness, substrate elasticity, fluid flow, and the shapes of the cells is the main goal of the study. In this comprehensive analysis, a combination of the fluid structure interaction method and the submodeled finite element technique was employed to anticipate the mechanical responses across various cells at the interface between cells and the substrate. Fluid inlet velocity, substrate roughness, and substrate material were varied in this analysis. Different cell shapes were considered along with various components such as cell membrane, cytoplasm, nucleus, and cytoskeletons. This analysis shows the effect of these individual parameters on the elastic strain and strain energy density of cells at the cell‐substrate interface. The results highlight that substrate roughness has a more significant impact on the mechanical response of cells at the interface than substrate elasticity. However, effect of the substrate elasticity becomes crucial for extremely soft substrate materials. The results of this research can be applied to identify the optimal parameters for fluid flow and create a suitable condition for cell culture. [ABSTRACT FROM AUTHOR]

Both cell migration and osteogenic differentiation are critical for successful bone regeneration. Therefore, understanding the mechanobiological aspects that govern these two processes is essential in designing effective scaffolds that promote faster bone regeneration. Studying these two factors at different locations is necessary to manage bone regeneration in various sections of a scaffold. Hence, a multiscale computational model was used to observe the mechanical responses of osteoblasts placed in different positions of the trabecular bone and gyroid scaffold. Fluid shear stresses in scaffolds at cell seeded locations (representing osteogenic differentiation) and strain energy densities in cells at cell substrate interface (representing cell migration) were observed as mechanical response parameters in this study. Comparison of these responses, as two critical factors for bone regeneration, between the trabecular bone and gyroid scaffold at different locations, is the overall goal of the study. This study reveals that the gyroid scaffold exhibits higher osteogenic differentiation and cell migration potential compared to the trabecular bone. However, the responses in the gyroid only mimic the trabecular bone in two out of nine positions. These findings can guide us in predicting the ideal cell seeded sites within a scaffold for better bone regeneration and in replicating a replaced bone condition by altering the physical parameters of a scaffold. [ABSTRACT FROM AUTHOR]

Cure models are widely popular in modeling time-to-event data that are characterized by cure fraction owing to long-term survivors. Mixture cure models are perhaps the most studied cure models in the literature. In this article, however, we consider a competing risks scenario where the number of competing causes is modeled by flexible Conway-Maxwell (COM) Poisson distribution, and the lifetimes corresponding to the competing causes are assumed to be independently distributed following proportional hazards model. The baseline hazard function is modeled by a piecewise linear function, and hence, estimated non parametrically. Probability of obtaining zero competing causes is used to estimate the cure rate. Collectively, the resultant cure model is exceedingly general and flexible. The estimation of the parameters is carried out using maximum likelihood (ML) method by implementing the expectation-maximization (EM) algorithm, except for the dispersion parameter of the COM-Poisson distribution, which is estimated by the profile likelihood method. The performance of the model is tested under various settings of censoring rate, sample size and mean lifetime. Discrimination of models is performed and carried out with likelihood-based and information-based criteria. Performance of the proposed model is further illustrated using a real-world data on cutaneous melanoma. [ABSTRACT FROM AUTHOR]

This article aims to manifest a new way of the utilization of renewable resources in a distribution network. Solar power acts as a source of excitation in the field winding of a separately excited biogas DC generator for the generation of DC power. The amount of DC power required by the generator's field winding is supplied by harnessing a minimum amount of solar energy from a solar photovoltaic (solar PV) for the operation of the bio-power generator of a rated capacity of 5 kW. It is observed, that the availability of 5% peak solar power can be utilized for full excitation of the generator and, it is observed that the full load demand at the time around 16:00 pm can be catered only by the bio-generator. In this work, it has been acknowledged that solar power can be effectively used in low insolation. In addition, it has been revealed, no auxiliary power source is needed for the operation of the generator approximately, 330.22 W of DC power is required by the field winding for full excitation of the DC generator. The present research developed a unique way of power management strategy, which can mitigate the delicate problems in a conventional distribution system. [ABSTRACT FROM AUTHOR]

Functionalized hydrogels, with their unique and adaptable structures, have attracted significant attention in materials and biomaterials research. Fluorescent hydrogels are particularly noteworthy for their sensing capabilities and ability to mimic cellular matrices, facilitating cell infiltration and tracking of drug delivery. Structural elucidation of hydrogels is crucial for understanding their responses to stimuli such as the pH, temperature, and solvents. This study developed a fluorescent hydrogel by functionalizing chitosan with p -cresol-based quinazolinone aldehyde. Confocal microscopy revealed the hydrogel's intriguing fluorogenic properties. The hydrogel exhibited enhanced fluorescence and a tunable network morphology, influenced by the THF-water ratio. The study investigated the control of gel network reformation in different media and analyzed the fluorescence responses and structural changes of the sugar backbone and fluorophore. Proper selection of mixed solvents is essential for optimizing the hydrogel as a fluorescence probe for bioimaging. This hydrogel demonstrated greater swelling properties, making it highly suitable for drug delivery applications.

Objectives: Patients with type 2 diabetes or prolonged diabetic condition are webbed into cardiac complications. This study aimed to ascertain the utility of chick embryo as an alternative to the mammalian model for type 2 diabetes-induced cardiac complications and chrysin as a protective agent., Methods: Diabetes was activated in ovo model (chick embryo) using glucose along with β-hydroxybutyric acid. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, Alamar, and Kenacid blue assay were used to compare with chrysin-administered group. Blood glucose level, total cholesterol, triglyceride, and high-density lipoprotein were considered as endpoints. Diabetes was induced in Wistar albino rats by administering a high-fat diet and a subdued dose of streptozotocin (35 mg/kg, b.w). Percentage of glycated hemoglobin, creatinine kinase-MB, tumor necrosis factor-α, and C-reactive protein were evaluated and compared with chrysin administered group., Key Findings: Chrysin treatment improved elevated blood glucose levels and dyslipidemia in a diabetic group of whole embryos. Condensed cellular growth and protein content as well as enhanced cytotoxicity in ovo were shielded by chrysin. Chrysin reduced cardiac and inflammatory markers in diabetic rats and provided cellular protection to damage the heart of diabetic rats., Conclusion: The protective action of chrysin in ovo model induced a secondary complication associated with diabetes, evidenced that the ovo model is an effective alternative in curtailing higher animal use in scientific research., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)