Superspreading on hydrophobic substrates:effect of glycerol additive

The spreading of solutions of three trisiloxane surfactants on two hydrophobic substrates, polyethylene and polyvinylidenefluoride, was studied with the addition of 0–40 mass % of glycerol. It was found that all the surfactant solutions spread faster than silicone oil of the same viscosity, confirming the existence of a mechanism which accelerates the spreading of the surfactant solutions. For the non-superspreading surfactant, BT-233, addition of glycerol improved the spreading performance on polyvinylidenefluoride and resulted in a transition from partial to complete wetting on polyethylene. The fastest spreading was observed for BT-233 at a concentration of 2.5 g/L, independent of glycerol content. For the superspreading surfactants, BT-240 and BT-278, the concentration at which the fastest spreading occurs systematically increased with concentration of glycerol on both substrates from 1.25 g/L for solutions in water to 10 g/L for solutions in 40% glycerol/water mixture. Thus, the surfactant equilibration rate (and therefore formation of surface tension gradients) and Marangoni flow are important components of a superspreading mechanism. De-wetting of the solutions containing glycerol, once spread on the substrates, resulted in the formation of circular drop patterns. This is in contrast to the solely aqueous solutions where the spread film shrank due to evaporation, without any visible traces being left behind

3D printed SrNbO2N photocatalyst for degradation of organic pollutants in water

Organic pollutants in water are a major concern for the environment and human health, and require urgent attention. Here, we developed for the first time monolithic structures by 3D printing of perovskite metal oxynitride, SrNbO2N, for photocatalytic degradation of organic pollutant in water. Advanced, synchrotron-based XRD-CT measurements were employed to gain structural insight into photocatalyst formulation and assess the fidelity of design in terms of both the chemical and physical form of the photocatalysts to be imaged. Our 3D printed material showed excellent photocatalytic activity, degrading 100% of methylene blue (MB) as well as good stability for three cycle operations. This is due to high adsorption of the 3D printed oxynitride towards MB which enhanced its photoredox reactivity. It is also evident from the excellent charge transfer demonstrating a charge transfer rate of (1.5 ± 0.2) × 108 s−1. We performed Time-Dependent Density Functional Theory (TD-DFT) calculations to understand the photocatalyst structure and degradation pathways. Our calculated band gap (at Γ) of 1.88 eV is in good agreement with the experimental values. We found that the highest valence bands were contributed by N p orbitals and the lowest conduction bands corresponded to Nb d orbitals offering avenues for fine-tuning the band gap. Hence, the ability to tailor photocatalyst monoliths by 3D printing renders their water treatment application more facile compared to their powder suspension counterparts

3D printed SrNbO₂N photocatalyst for degradation of organic pollutants in water

Organic pollutants in water are a major concern for the environment and human health, and require urgent attention. Here, we developed for the first time monolithic structures by 3D printing of perovskite metal oxynitride, SrNbO2N, for photocatalytic degradation of organic pollutant in water. Advanced, synchrotron-based XRD-CT measurements were employed to gain structural insight into photocatalyst formulation and assess the fidelity of design in terms of both the chemical and physical form of the photocatalysts to be imaged. Our 3D printed material showed excellent photocatalytic activity, degrading 100% of methylene blue (MB) as well as good stability for three cycle operations. This is due to high adsorption of the 3D printed oxynitride towards MB which enhanced its photoredox reactivity. It is also evident from the excellent charge transfer demonstrating a charge transfer rate of (1.5 ± 0.2) × 108 s−1. We performed Time-Dependent Density Functional Theory (TD-DFT) calculations to understand the photocatalyst structure and degradation pathways. Our calculated band gap (at Γ) of 1.88 eV is in good agreement with the experimental values. We found that the highest valence bands were contributed by N p orbitals and the lowest conduction bands corresponded to Nb d orbitals offering avenues for fine-tuning the band gap. Hence, the ability to tailor photocatalyst monoliths by 3D printing renders their water treatment application more facile compared to their powder suspension counterparts

Young children's flexible use of semantic cues to word meanings: converging evidence of individual and age differences

A new test of children’s flexible use of semantic cues for word learning extended previous results. In Experiment 1, three- to five-year-olds (N=51) completed two tests of interpreting several novel words for the same stimulus arrays. Within-sentence phrasal cues implied different stimulus referent properties. Children’s cue-using flexibility in the new Flexible Induction of Meanings [Words for Animates] test (FIM-An) was strongly correlated with an established test (Flexible Induction of Meanings [Words for Objects] ; Deak, 2000). Individual children showed between-test consistency in using cues to flexibly assign words to different referent properties. There were large individual differences, as well as limited age differences, in the distribution of flexible and inflexible response patterns. The comprehensibility of specific cues, and perceptual salience of specific properties, explained much of the variance. Proportions of flexible and inflexible patterns shifted with age. Experiment 2 replicated these results in N=36 three- and four-year-olds, using a modified FIM-An with more distinctive cues

Influence of blood pulsation on diagnostic volume in pulse oximetry and photoplethysmography measurements

Recent advances in the development of ultra-compact semiconductor lasers and technology of printed flexible hybrid electronics have opened broad perspectives for the design of new pulse oximetry and photoplethysmography devices. Conceptual design of optical diagnostic devices requires careful selection of various technical parameters, including spectral range; polarization and intensity of incident light; actual size, geometry, and sensitivity of the detector; and mutual position of the source and detector on the surface of skin. In the current study utilizing a unified Monte Carlo computational tool, we explore the variations in diagnostic volume due to arterial blood pulsation for typical transmitted and back-scattered probing configurations in a human finger. The results of computational studies show that the variations in diagnostic volumes due to arterial pulse wave are notably (up to 45%) different in visible and near-infrared spectral ranges in both transmitted and back-scattered probing geometries. While these variations are acceptable for relative measurements in pulse oximetry and/or photoplethysmography, for absolute measurements, an alignment normalization of diagnostic volume is required and can be done by a computational approach utilized in the framework of the current study

Early Evolution of Modern Birds Structured by Global Forest Collapse at the End-Cretaceous Mass Extinction

The fossil record and recent molecular phylogenies support an extraordinary early-Cenozoic radiation of crown birds (Neornithes) after the Cretaceous-Paleogene (K-Pg) mass extinction [1–3 ]. However, questions remain regarding the mechanisms underlying the survival of the deepest lineages within crown birds across the K-Pg boundary, particularly since this global catastrophe eliminated even the closest stem-group relatives of Neornithes [4 ]. Here, ancestral state reconstructions of neornithine ecology reveal a strong bias toward taxa exhibiting predominantly non-arboreal lifestyles across the K-Pg, with multiple convergent transitions toward predominantly arboreal ecologies later in the Paleocene and Eocene. By contrast, ecomorphological inferences indicate predominantly arboreal lifestyles among enantiornithines, the most diverse and widespread Mesozoic avialans [5–7 ]. Global paleobotanical and palynological data show that the K-Pg Chicxulub impact triggered widespread destruction of forests [8, 9 ]. We suggest that ecological filtering due to the temporary loss of significant plant cover across the K-Pg boundary selected against any flying dinosaurs (Avialae [10 ]) committed to arboreal ecologies, resulting in a predominantly non-arboreal postextinction neornithine avifauna composed of totalclade Palaeognathae, Galloanserae, and terrestrial total-clade Neoaves that rapidly diversified into the broad range of avian ecologies familiar today. The explanation proposed here provides a unifying hypothesis for the K-Pg-associated mass extinction of arboreal stem birds, as well as for the post-K-Pg radiation of arboreal crown birds. It also provides a baseline hypothesis to be further refined pending the discovery of additional neornithine fossils from the Latest Cretaceous and earliest Paleogene.Also supported by:- a 50th Anniversary Prize Fellowship at the University of Bath.- a Smithsonian NMNH Deep Time Peter Buck Postdoctoral Fellowship.- NSF grants DGE-1650441 and DEB-1700786.</p

Anti-cancer effects and mechanism of actions of aspirin analogues in the treatment of glioma cancer

INTRODUCTION: In the past 25 years only modest advancements in glioma treatment have been made, with patient prognosis and median survival time following diagnosis only increasing from 3 to 7 months. A substantial body of clinical and preclinical evidence has suggested a role for aspirin in the treatment of cancer with multiple mechanisms of action proposed including COX 2 inhibition, down regulation of EGFR expression, and NF-κB signaling affecting Bcl-2 expression. However, with serious side effects such as stroke and gastrointestinal bleeding, aspirin analogues with improved potency and side effect profiles are being developed. METHOD: Effects on cell viability following 24 hr incubation of four aspirin derivatives (PN508, 517, 526 and 529) were compared to cisplatin, aspirin and di-aspirin in four glioma cell lines (U87 MG, SVG P12, GOS – 3, and 1321N1), using the PrestoBlue assay, establishing IC50 and examining the time course of drug effects. RESULTS: All compounds were found to decrease cell viability in a concentration and time dependant manner. Significantly, the analogue PN517 (IC50 2mM) showed approximately a twofold increase in potency when compared to aspirin (3.7mM) and cisplatin (4.3mM) in U87 cells, with similar increased potency in SVG P12 cells. Other analogues demonstrated similar potency to aspirin and cisplatin. CONCLUSION: These results support the further development and characterization of novel NSAID derivatives for the treatment of glioma

A three gene DNA methylation biomarker accurately classifies early stage prostate cancer

Background: We identify and validate accurate diagnostic biomarkers for prostate cancer through a systematic evaluation of DNA methylation alterations. Materials and methods: We assembled three early prostate cancer cohorts (total patients = 699) from which we collected and processed over 1300 prostatectomy tissue samples for DNA extraction. Using real-time methylation-specific PCR, we measured normalized methylation levels at 15 frequently methylated loci. After partitioning sample sets into independent training and validation cohorts, classifiers were developed using logistic regression, analyzed, and validated. Results: In the training dataset, DNA methylation levels at 7 of 15 genomic loci (glutathione S-transferase Pi 1 [GSTP1], CCDC181, hyaluronan, and proteoglycan link protein 3 [HAPLN3], GSTM2, growth arrest-specific 6 [GAS6], RASSF1, and APC) showed large differences between cancer and benign samples. The best binary classifier was the GAS6/GSTP1/HAPLN3 logistic regression model, with an area under these curves of 0.97, which showed a sensitivity of 94%, and a specificity of 93% after external validation. Conclusion: We created and validated a multigene model for the classification of benign and malignant prostate tissue. With false positive and negative rates below 7%, this three-gene biomarker represents a promising basis for more accurate prostate cancer diagnosis

Characterization of Clinically-Attenuated Burkholderia mallei by Whole Genome Sequencing: Candidate Strain for Exclusion from Select Agent Lists

is an understudied biothreat agent responsible for glanders which can be lethal in humans and animals. Research with this pathogen has been hampered in part by constraints of Select Agent regulations for safety reasons. Whole genomic sequencing (WGS) is an apt approach to characterize newly discovered or poorly understood microbial pathogens. genome. Therefore, the strain by itself is unlikely to revert naturally to its virulent phenotype. There were other genes present in one strain and not the other and vice-versa. was both avirulent in the natural host ponies, and did not possess T3SS associated genes may be fortuitous to advance biodefense research. The deleted virulence-essential T3SS is not likely to be re-acquired naturally. These findings may provide a basis for exclusion of SAVP1 from the Select Agent regulation or at least discussion of what else would be required for exclusion. This exclusion could accelerate research by investigators not possessing BSL-3 facilities and facilitate the production of reagents such as antibodies without the restraints of Select Agent regulation

A Novel Anti-CEACAM5 Monoclonal Antibody, CC4, Suppresses Colorectal Tumor Growth and Enhances NK Cells-Mediated Tumor Immunity

Carcinoembryonic antigen (CEA, CEACAM5, and CD66e) has been found to be associated with various types of cancers, particularly colorectal carcinoma, and developed to be a molecular target for cancer diagnosis and therapy. In present study, we generated a novel anti-CEACAM5 monoclonal antibody, namely mAb CC4, by immunizing mice with living colorectal cancer LS174T cells. Immunohistochemical studies found that mAb CC4 specifically and strongly binds to tumor tissues, especially colorectal adenocarcinoma. In xenografted mice, mAb CC4 is specifically accumulated in tumor site and remarkably represses colorectal tumor growth. In vitro functional analysis showed that mAb CC4 significantly suppresses cell proliferation, migration and aggregation of colorectal cancer cells and also raises strong ADCC reaction. More interestingly, mAb CC4 is able to enhance NK cytotoxicity against MHC-I-deficient colorectal cancer cells by blocking intercellular interaction between epithelial CEACAM5 and NK inhibitory receptor CEACAM1. These data suggest that mAb CC4 has the potential to be developed as a novel tumor-targeting carrier and cancer therapeutic