Many natural micrometre-scale assemblies can be actuated to control their optical, transport and mechanical properties, yet such functionality is lacking in colloidal structures synthesized thus far. ...Here, we show with experiments and computer simulations that Janus ellipsoids can self-assemble into self-limiting one-dimensional fibres with shape-memory properties, and that the fibrillar assemblies can be actuated on application of an external alternating-current electric field. Actuation of the fibres occurs through a sliding mechanism that permits the rapid and reversible elongation and contraction of the Janus-ellipsoid chains by ~36% and that on long timescales leads to the generation of long, uniform self-assembled fibres. Colloidal-scale actuation might be useful in microrobotics and in applications of shape-memory materials.
The self-assembly of colloidal crystals is important to the production of materials with functional optical, mechanical and conductive properties. Yet, self-assembly methods are limited by their slow ...kinetics and lack of structural control in space and time. Refinements such as templating and directed assembly partially address the problem, albeit by introducing fixed surface features such as templates or electrodes. A template-free method to reconfigure colloidal crystals simultaneously in three-dimensional space and time would better align work in colloidal assembly with materials applications. Here, we report a photo-induced assembly method that yields regions either filled with colloidal crystals or completely devoid of colloids. The origin of the effect is found to be electrophoresis of colloids generated by photochemistry at an indium tin oxide-coated substrate. Simple optical manipulations are applied to reconfigure these assembly and depletion regions. Thus, the method represents a new kind of template-free, reconfigurable three-dimensional photolithography.
We report a method to synthesize and image Janus spheroid and "kayak" shaped patchy particles that combine both shape and interaction anisotropy. These particles are fabricated by sequentially ...combining evaporative deposition of chrome and gold with the uniaxial deformation of the colloidal particles into spheroids. We introduce combined reflection and fluorescence confocal microscopy to image each component of the patchy particle. Image analysis algorithms that resolve patch orientation from these image volumes are described and used to characterize self-assembly behavior. Assemblies of the Janus spheroid and kayak particles produced at different salt concentrations demonstrate the functional nature of the patch-to-patch interactions between the particles. Selective gold-to-gold patch bonding is observed at intermediate salt concentrations, while higher salt concentrations yield gel-like structures with nonselective patch-to-patch bonding. At intermediate salt concentrations, differences in the orientational order of the assemblies indicate that both the preferential gold-to-gold patch bonding and the particles' shape anisotropy influence the self-assembled structure.
We performed a prospective observational study of 215 patients (58 ± 11 years) and compared the outcomes of ultrasound guided ulnar (n = 98, 45.6%) vs. radial (n = 117, 54.4%) cardiac catheterization ...and percutaneous coronary intervention (PCI) in patients selected by an ultrasound based algorithm. Primary endpoints included the number of access attempts and conversion to femoral access. Secondary endpoints included all-cause mortality, cardiac mortality, myocardial infarction, stroke, repeat revascularization, stent thrombosis, in-stent restenosis, and access site complications.
No significant difference was found in the primary endpoints between radial or ulnar. Ulnar access showed no significant hematomas. Therefore, ulnar PCI is a feasible alternative.
DC electric fields are used to produce colloidal assemblies with orientational and layered positional order from a dilute suspension of spheroidal particles. These 3D assemblies, which can be ...visualized in situ by confocal microscopy, are achieved in short time spans (t < 1 h) by the application of a constant voltage across the capacitor‐like device. This method yields denser and more ordered assemblies than had been previously reported with other assembly methods. Structures with a high degree of orientational order as well as layered positional order normal to the electrode surface are observed. These colloidal structures are explained as a consequence of electrophoretic deposition and field‐assisted assembly. The interplay between the deposition rate and the rotational Brownian motion is found to be critical for the optimal ordering, which occurs when these rates, as quantified by the Peclet number, are of order one. The results suggest that the mechanism leading to ordering is equilibrium self‐assembly but with kinetics dramatically accelerated by the application of the DC electric field. Finally, the crystalline symmetry of the densest structure formed is determined and compared with previously studied spheroidal assemblies.
Rapid assembly of anisotropic colloidal particles is essential to create complex, uniform, and scalable crystal structures for applications. In this study, DC electric fields are used to accelerate the self‐assembly process of spheroidal particles. The image shows confocal microscopy images and renderings from image processing of the field‐induced 3D ordering. The assembly is shown to have high‐quality orientational order and previously unobserved periodic and dense layered ordering.
Supervised machine learning, in which models are automatically derived from labeled training data, is only as good as the quality of that data. This study builds on prior work that investigated to ...what extent “best practices” around labeling training data were followed in applied ML publications within a single domain (social media platforms). In this paper, we expand by studying publications that apply supervised ML in a far broader spectrum of disciplines, focusing on human-labeled data. We report to what extent a random sample of ML application papers across disciplines give specific details about whether best practices were followed, while acknowledging that a greater range of application fields necessarily produces greater diversity of labeling and annotation methods. Because much of machine learning research and education only focuses on what is done once a “ground truth” or “gold standard” of training data is available, it is especially relevant to discuss issues around the equally important aspect of whether such data is reliable in the first place. This determination becomes increasingly complex when applied to a variety of specialized fields, as labeling can range from a task requiring little-to-no background knowledge to one that must be performed by someone with career expertise.
We studied the interaction between capsule production and hydrodynamic growth conditions on the internal and macroscopic structure of biofilms and spontaneously formed aggregates of Klebsiella ...pneumoniae. Wild-type and capsule-deficient strains were studied as biofilms and under strong and mild hydrodynamic conditions. Internal organization of multicellular structures was determined with a novel image-processing algorithm for feature extraction from high-resolution confocal microscopy. Measures included interbacterial spacing and local angular alignment of individual bacteria. Macroscopic organization was measured via the size distribution of aggregate populations forming under various conditions. Compared with wild-type organisms, unencapsulated mutant organisms formed more organized aggregates with less variability in interbacterial spacing and greater interbacterial angular alignment. Internal aggregate structure was not detectably affected by the severity of hydrodynamic growth conditions. However, hydrodynamic conditions affected both wild-type and mutant aggregate size distributions. Bacteria grown under high-speed shaking conditions (i.e., at Reynolds' numbers beyond the laminar-turbulent transition) formed few multicellular aggregates while clumpy growth was common in bacteria grown under milder conditions. Our results indicate that both capsule and environment contribute to the structure of communities of K. pneumoniae, with capsule exerting influence at an interbacterial length scale and fluid dynamic forces affecting overall particle size.
Examine video-based motion analysis (VBMA) use among sports physical therapists.
Cross-sectional observation.
Survey, online-platform.
American Academy of Sports Physical Therapy members (n = 261).
...VBMA use frequency, reasons for use, facilitators/barriers, tools used, factors associated with use.
194 (74.3%) used VBMA but 163 (84%) use it for ≤ 25% of their caseload. Most (57.7%) used their personal device to capture VBMA. Commonly cited reasons for use were movement analysis (93.8%) and patient education (87.6%). Barriers to use included time (30.7%), unfamiliarity with device/equipment (19.2%), and lack of device/equipment (18.4%). Younger age, advanced training, and greater time spent with return patients were each associated with use. For every 5-year increase of age, there was a 12% reduced likelihood of VBMA use (OR = 0.88; 95% CI = 0.77–1.00). Board-certified sports clinical specialists were more likely to use vs. those without additional certifications/degrees (OR = 3.27; 95% CI = 1.33–8.02). Spending 30–59 (vs. <30) minutes with return patients increased the odds of use (ORs range: 2.71 to 3.85).
Most respondents used VBMA, albeit infrequently. Those younger, with advanced training, and spending ≥30 min with return patients were more likely to use VBMA. Future research should investigate whether VBMA use enhances patient outcomes.
•Most sports physical therapists in the United States used VBMA, albeit infrequently.•Younger age, advanced training, and time with return patients predicted VBMA use.•Movement analysis and visual feedback for patients were primary reasons for VBMA use.•Time restraint, unfamiliarity, and lack of equipment were common barriers to VBMA use.
•We examined the effect of IL-26, a newly reported antimicrobial peptide, against bb DNA.•An antimicrobial effect of IL-26 on the spirochete was observed.•IL-26-treated human macrophages showed an ...increase in both NF-kB and IRF activation upon bb stimulation.•IL-26-treated macrophages showed an increased in phagocytic activity compared to untreated cells.•A bacterial comet assay showed cellular and bb DNA degradation by IL-26.
Lyme disease is an inflammatory disease caused by infection with Borrelia burgdorferi (Bb). Inflammatory sequelae of Bb infection appear to be refractory to antibiotics. An antimicrobial peptide with the ability to bind the DNA in the tissue could serve as a viable option of treatment for chronic complications of Lyme borreliosis. DNA of Bb can remain in tissues causing a prolonged inflammatory response that lead to chronic joint pain. Here we examined the effect of IL-26, a newly reported antimicrobial protein, against Bb DNA.
An antimicrobial effect of IL-26 on the spirochete was observed. In human macrophages, IL-26 treated cells showed an increase in IRF activation upon Bb stimulation. Moreover, IL-26 treated macrophages showed an increased in phagocytic activity compared to untreated cells. Although no Bb DNA degradation was observed using a TUNEL assay run in an agarose gel, a Comet assay on whole bacteria showed cellular and Bb DNA degradation by IL-26.
Our results showed that IL-26 (monomer and dimer) has not only the potential to control Bb growth in vitro, but it also enhances the anti-borrelial response of human macrophages. Further research aiming to characterize the role of IL-26 in controlling other aspects of the inflammatory response that could provide insight of its potential therapeutic applications are needed.
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