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Several fundamental research and applications in biomedicine and microfluidics often require controlled manipulation of suspended micro- and nanoscale particles. Speckle tweezers (ST) by incorporating randomly distributed light fields have been used to control micro-particles with refractive indices higher than their medium and to perform manipulation tasks such as guiding and sorting. Indeed, compared to periodic potentials, ST represents a wider possibility to be operated for such tasks. Here, we extend the usefulness of ST into micro-particles of low index with respect to the surrounding. Repelling of such particles by high intensity regions into lower intensity regions makes them to be locally confined, and the confinement can be tuned by changing the average grain intensity and size of the speckle patterns. Experiments on polystyrenes and liposomes validate the procedure. Moreover, we show that ST can also manipulate the nano-particle (NP)-loaded liposomes. Interestingly, the different interactions of NP-loaded and empty liposomes with ST enable collective manipulation of their mixture using the same speckle pattern, which may be explained by inclusion of the photophoretic forces on NPs. Our results on the different behaviors between empty and non-empty vesicles may open a new window on controlling collective transportation of drug micro-containers along with its wide applications in soft matter.

Introduction: Interventions using 'hybrid' remediation/compensatory cognitive interventions may be beneficial to improving the socio-cognitive functioning of children with autism spectrum disorder (ASD). Previous studies have shown that neurocognitive impairments in executive function (EF) and theory of mind (TOM) are specifically associated with ASD. The primary objective of the study is to determine the impact of the remediation and compensatory cognitive intervention on EFs and TOM abilities. The secondary objective is to evaluate TOM and EF behavioral domains due to the remediation and compensatory cognitive intervention. Methods: A total of 75 children aged 4 to 7 years diagnosed with high-functioning autism and their parents will be recruited to this double-blind, multicenter, multi-arm randomized controlled trial. The primary outcomes are EFs and TOM as measured by the shape school, shape span test, TOM scale, TOM story books, TOM assessment checklist, and EFs assessment checklist. The secondary outcome is EFs and TOM behavioral domains as measured by the TOM behavior checklist and brief-preschool version at baseline (T0), post-test (T1), 1-month follow-up (T2), and 3-month follow-up (T3). Primary and secondary outcomes will be analyzed using repeated measures, such as an analysis of variance and a mixed model. Conclusion: This study will assess whether the cognitive intervention program affects not only the neuropsychological functioning of children with ASD but also daily functioning. If the current trial shows that either the remediation or compensatory approaches effectively improve socio-cognitive functioning, the trial would reveal a 'hybrid' remediation/compensatory approach. [ABSTRACT FROM AUTHOR]

Symptoms evoked in individuals with posttraumatic stress disorder (PTSD) when processing trauma-relevant material arguably impair higher order cognitive functions. An example is working memory capacity (WMC), which has been shown to be disrupted by affective distractors. However, it is unknown whether this association varies across different types of PTSD symptoms. This study explored the association between WMC performed in affective (relative to neutral) contexts in relation to different symptoms of PTSD (avoidance, re-experiencing, hyperarousal). Motor vehicle accident survivors with PTSD and without PTSD completed a delayed-match-to-sample task including trauma-related, neutral, and scrambled distractors in the interval between the presentation of the memoranda and the recognition target. The results showed that there was support for an indirect pathway between PTSD diagnosis and WMC performed in affective (versus neutral) contexts through re-experiencing and avoidance symptoms. The findings suggest that avoidance symptoms in particular may benefit from interventions directed at improving WMC.

The local and global behavior of reinforced concrete (RC) members and structures may be affected by cracks and the capabilities of stress transfer mechanisms. Dowel action is one of the shear transfer mechanisms across RC cracks and particularly is the only mechanism in pre-formed joints that are common in precast concrete connections. Herein, the path-dependent behavior of dowel action mechanism is examined experimentally and analytically. Firstly, the effect of loading history and direction on the shear transfer capabilities of crossing bars are investigated experimentally. Then, according to the experimental results and observations, a model is extended to simulate and capture the directional path-dependent behavior of dowel action by introducing consistent formulas for subgrade springs based on the beam on the elastic foundation analogy. Verification is carried out by comparing with the corresponding experimental results and shows the fair accuracy of the proposed model and assumptions. Key words: dowel action, shear, RC crack, RC joints, shear transfer. Le comportement local et global des membrures/structures en beton arme (BA) peut etre modifie par les fissures et les capacites des mecanismes de transfert de l'effort tranchant. L'action de goujon est un des mecanismes de transfert de l'effort tranchant a travers des fissures dans le beton et en particulier est le seul mecanisme dans les joints preformes qui sont communs dans les raccords de beton prefabrique. Dans cette etude, le comportement dependant du chemin du mecanisme d'action de goujon est examine de maniere experimentale et analytique. Premierement, on examine experimentalement l'effet de l'historique et de la direction du chargement sur les capacites de transfert de l'effort tranchant de barres croisees. Ensuite, selon les observations et les resultats experimentaux, un modele est modifie afin de simuler et capturer le comportement dependant du chemin directionnel d'action de goujon en presentant des formules coherentes pour des ressorts de sol de fondation en se fondant sur l'analogie de la poutre sur fondation elastique. La verification est effectuee en faisant la comparaison avec les resultats experimentaux correspondants et celle-ci montre une bonne exactitude du modele propose et des hypotheses. [Traduit par la Redaction] Mots-cles : action de goujon, effort tranchant, fissure dans le beton arme, joints dans le beton arme, transfert de l'effort tranchant., 1. Introduction Reinforced concrete (RC) cracks, joints, and stress-induced discontinuities may turn into weak planes that can affect the local and global behavior of RC members and structures. Without having [...]

Introduction: Modeling the blood-brain barrier has long been a challenge for pharmacological studies. Up to the present, numerous attempts have been devoted to recapitulating the endothelial barrier in vitro to assess drug delivery vehicles’ efficiency for brain disorders. In the current work, we presented a new approach for analyzing the morphometric parameters of the cells of an insert coculture blood-brain barrier model using rat brain astrocytes, rat brain microvascular endothelial cells, and rat brain pericytes. This analytical approach could aid in getting further information on drug trafficking through the blood-brain barrier and its impact on the brain indirectly. Methods: In the current work, we cultured rat brain astrocytes, rat brain microvascular endothelial cells, and rat brain pericytes and then used an insert well to culture the cells in contact with each other to model the blood-brain barrier. Then, the morphometric parameters of the porous membrane of the insert well, as well as each cell type were imaged by digital holographic microscopy before and after cell seeding. At last, we performed folate conjugation on the surface of the EVs we have previously tested for glioma therapy in our previous work called VEGF-A siDOX-EVs and checked how the trafficking of EVs improves after folate conjugation as a clathrin-mediated delivery setup. the trafficking and passage of EVs were assessed by flow cytometry and morphometric analysis of the digital holographic microscopy holograms. Results: Our results indicated that EVs successfully entered through the proposed endothelial barrier assessed by flow cytometry analysis and furthermore, folate conjugation significantly improved EV passage through the blood-brain barrier. Moreover, our results indicated that the VEGF-A siDOX-EVs insert cytotoxic impact on the cells of the bottom of the culture plate. Conclusion: folate-conjugation on the surface of EVs improves their trafficking through the blood-brain barrier and by using digital holographic microscopy analysis, we could directly assess the morphometric changes of the blood-brain barrier cells for pharmacological purposes as an easy, labelfree, and real-time analysis. [ABSTRACT FROM AUTHOR]