Development of chitosan-gelatin nanofibers with cellulose nanocrystals for skin protection applications

In this work, natural-based and biodegradable nanofibers were produced by electrospinning for drug delivery and wound dressing applications, using gelatin (Gel), chitosan (CS), cellulose nanocrystals (CNC) and natural propolis extract. The polymeric formulations and electrospinning parameters were optimized, resulting in the development of Gel/CS nanofibers with mean diameters of 97 nm. CNC were successfully introduced into the optimized Gel/CS solution and the viscosity and conductivity values were recorded. The developed nanofibers were characterized using FESEM, ATR-FTIR, TGA and WCA. The incorporation of different CNC concentrations improved the solutions’ electrospinnability and the membranes’ physical integrity. Defect-free and uniform Gel/CS/CNC nanofibers were observed by FESEM images, and the fibers’ diameters slight increased. The hydrophilic character was maintained after the CNC incorporation. Finally, Gel/CS/CNC/Propolis nanofibers demonstrated antibacterial activity against both Gram-negative (E. coli) and Gram-positive (S. aureus) bacteriaThe authors are thankful to TSSiPRO project, operation code NORTE01-0145-FEDER-000015. The authors are also grateful to FCT, Portugal for financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020) and to 2C2T (UID/CTM/00264/2019). D. P. Ferreira thank the national funding by FCT through the individual scientific employment program-contract (CEECIND/02803/2017) and S. M. Costa thank the FCT PhD Scholarship (SFRH/BD/147517/2019)

Density reconstruction from biased tracers and its application to primordial non-Gaussianity

Large-scale Fourier modes of the cosmic density field are of great value for learning about cosmology because of their well-understood relationship to fluctuations in the early universe. However, cosmic variance generally limits the statistical precision that can be achieved when constraining model parameters using these modes as measured in galaxy surveys, and moreover, these modes are sometimes inaccessible due to observational systematics or foregrounds. For some applications, both limitations can be circumvented by reconstructing large-scale modes using the correlations they induce between smaller-scale modes of an observed tracer (such as galaxy positions). In this paper, we further develop a formalism for this reconstruction, using a quadratic estimator similar to the one used for lensing of the cosmic microwave background. We incorporate nonlinearities from gravity, nonlinear biasing, and local-type primordial non-Gaussianity, and verify that the estimator gives the expected results when applied to N-body simulations. We then carry out forecasts for several upcoming surveys, demonstrating that, when reconstructed modes are included alongside directly-observed tracer density modes, constraints on local primordial non-Gaussianity are generically tightened by tens of percents compared to standard single-tracer analyses. In certain cases, these improvements arise from cosmic variance cancellation, with reconstructed modes taking the place of modes of a separate tracer, thus enabling an effective "multitracer" approach with single-tracer observations.Comment: 30 pages plus 14 pages appendices, 19 figure

Directing human attention with pointing

© 2014 IEEE. Pointing is a typical means of directing a human's attention to a specific object or event. Robot pointing behaviours that direct the attention of humans are critical for human-robot interaction, communication and collaboration. In this paper, we describe an experiment undertaken to investigate human comprehension of a humanoid robot's pointing behaviour. We programmed a NAO robot to point to markers on a large screen and asked untrained human subjects to identify the target of the robots pointing gesture. We found that humans are able to identify robot pointing gestures. Human subjects achieved higher levels of comprehension when the robot pointed at objects closer to the gesturing arm and when they stood behind the robot. In addition, we found that subjects performance improved with each assessment task. These new results can be used to guide the design of effective robot pointing behaviours that enable more effective robot to human communication and improve human-robot collaborative performance

Protonated carbon nitride incorporated polyamide thin film nanocomposite for reverse osmosis desalination

Protonated carbon nitride (pCN) prepared from acid treatment of carbon nitride (CN) was incorporated in the polysulfone (PSf) substrate and polyamide (PA) layer to produce thin film nanocomposite (TFN) membrane. The hydrophilicity of CN is expected to improve the surface hydrophilicity of the membrane and acid treatment of nanoparticle is aimed to further enhance the surface structure and prevent the agglomeration of nanomaterial from taking place. pCN loading used in the PSf substrate was 0.5% while in the PA layer was varied as 0.05%, 0.1% and 0.15%. All the membrane prepared were characterized in terms of morphology, structural properties, and surface chemistry. Reverse osmosis dead-end filtration system was used to determine the water permeability and the salt rejection. It was observed that, all the membrane prepared could maintain the salt rejection with improvement of water permeability. However, the salt rejection was sacrificed when higher loading of 0.15% pCN was tested, although the water permeability of the membrane has reached approximately 0.5 LMHbar. This work demonstrates that the use of pCN in RO membrane can improve the water permeability without sacrificing the salt rejection

XML-VM: An XML-Based Grid Computing Middleware

This paper describes a novel distributing computing middleware named XML-VM. Its architecture is inspired by the \u2018Grid Computing\u2019 paradigm. The proposed system improves many characteristics of previous Grid systems, in particular the description of the distributed computation, the distribution of the code and the execution times. XML is a markup language commonly used to interchange arbitrary data over the Internet. The idea behind this work is to use XML to describe algorithms; XML documents are distributed by means of XML-RPC, interpreted and executed using virtual machines. XML-VM is an assembly-like language, coded in XML. Parsing of XML-VM programs is performed with a fast SAX parser for JAVA. XML-VM interpreter is coded in JAVA. Several algorithms are written in XML-VM and executed in a distributed environment. Representative experimental results are reported

Locked nailing for the treatment of displaced articular fractures of the calcaneus: description of a new procedure with calcanail®

Although open reduction and internal fixation is considered the best method for treating displaced articular fractures of the calcaneus, lateral approach is at high risk for wound healing complications. For this reason, the authors developed a posterior approach and a new implant to perform both intrafocal reduction and internal fixation. The aim of this technical note is to describe this method of treatment for displaced articular fractures of the calcaneus, which offered the following advantages: (a) the creation of a working channel that provides also a significant bone autograft, (b) the intrafocal reduction of the displaced articular surface, (c) the insertion of a locking nail that maintains the reduced articular surface at the right height, (d) the possibility to switch from an ORIF to a reconstruction arthrodesis with the same approach and instrumentation in case of severely damaged posterior facet