Enhanced visualization methods for interpretation of wind tunnel data

Journal of Visualization -     

Correction: Click activated protodrugs against cancer increase the therapeutic potential of chemotherapy through local capture and activation

Correction for ‘Click activated protodrugs against cancer increase the therapeutic potential of chemotherapy through local capture and activation’ by Kui Wu et al., Chem. Sci., 2021, 12, 1259–1271, DOI: 10.1039/D0SC06099B.

The authors regret that the reference to the bond-breaking bioorthogonal chemistry, termed ‘click-to-release’ was omitted from the original article. In addition, we would like to include a reference describing the synthesis of compound 1, which is an intermediate to the protodrugs described in the original article. These references are listed below as ref. 1 and 2.The Royal Society of Chemistry apologizes for these errors and any consequent inconvenience to authors and readers.     

Physico-chemical and anatomical characterization of residual lignocellulosic fibers

Anatomical and physico-chemical properties of residual natural fibers (sugarcane bagasse, coconut fibers and peanut hulls) were characterized in order to evaluate their potential for use in the production of particleboard. The bulk density was determined by helium pycnometer and the chemical characteristics by using an electronic pH meter (for pH determination) on fibers dissolved in acidic and neutral detergents (to determine the levels of cellulose, hemicellulose and lignin). The anatomical characteristics were established using scanning electron microscopy coupled with an X-ray detector system, as well as energy dispersive X-ray spectroscopy. Results indicated similarities and differences between physico-chemical and anatomical characteristics of the residual lignocellulosic fibers when compared with the Pinus sp. wood commercially employed in particleboard production. Bulk density and pH for residual lignocellulosic fibers and Pinus sp. wood presented analogous values. Similar amounts of cellulose and lignin were identified between waste fibers and Pinus sp. wood. The presence of silica was identified in coconut fiber, peanut hull and sugarcane bagasse waste fibers, and may affect the mechanical characteristics of panels. Coconut and sugarcane bagasse fibers show surface pores with diameters ranging from 1.2 to 2.1 μm, below the 5 μm identified for Pinus sp. wood. Both fibers present pores distributed over their entire surface, whereas peanut hull fibers have no pores on their surface. This characteristic contributes to resin dispersion among particles, reflecting positively on the physical–mechanical properties of the panels. Particleboards produced with residual lignocellulosic fibers present similar physical–mechanical properties to those of Pinus sp. wood panels.     

Effects of the dispersion methods in Pluronic F108 on the size and the surface composition of MWCNTs and their implications in toxicology assessment

Multi-walled carbon nanotubes (MWCNTs) were dispersed in water and in a Pluronic F108 solution by four different dispersion methods (stirring, bath sonication, stirring followed by bath sonication, and sonication probe). The effect of the dispersion methods were evaluated in terms of the particle size distribution, the agglomerates size, and the exfoliated fraction produced, as well as in terms of the surface and bulk chemical composition. Energy dispersive X-ray, X-ray photoelectron spectroscopy, and centrifugal liquid sedimentation techniques were used to characterize pristine MWCNTs and their dispersion. It is shown that, irrespective of the dispersion methods used, the MWCNTs are strongly wrapped with the biocompatible surfactant Pluronic F108, thereby modifying the external surface of the MWCNTs. Some shortening of MWCNTs and more wrapping are also observed when sonication methods are used. These observations raise questions as to the validity of results obtained in toxicology tests, in vitro and in vivo, were such methods of dispersion procedures are used.     

Active cancellation of occlusion: an electronic vent for hearing aids and hearing protectors

The occlusion effect is commonly described as an unnatural and mostly annoying quality of the voice of a person wearing hearing aids or hearing protectors. As a result, it is often reported by hearing aid users as a deterrent to wearing hearing aids. This paper presents an investigation into active occlusion cancellation. Measured transducer responses combined with models of an active feedback scheme are first examined in order to predict the effectiveness of occlusion reduction. The simulations predict 18 dB of occlusion reduction in completely blocked ear canals. Simulations incorporating a 1 mm vent (providing passive occlusion reduction) predict a combined active and passive occlusion reduction of 20 dB. A prototype occlusion canceling system was constructed. Averaged across 12 listeners with normal hearing, it provided 15 dB of occlusion reduction. Ten of the subjects reported a more natural own voice quality and an appreciable increase in comfort with the cancellation active, and 11 out of the 12 preferred the active system over the passive system.     

Planning midwifery services to deliver continuity of care

This paper describes a simulation model of maternity services which was developed to support the planning of midwifery services to meet demands for continuity of care. A Government report of maternity services in 1992 emphasised the need to replace the fragmented care offered to pregnant women by a more personalised type of approach. One way of doing this is by the implementation of team midwifery in which care is provided, antenatally, during labour, and then postnatally by either the same midwife or, more usually a small team of midwives.The model described in this paper attempts to assess the effects of team size upon the continuity of care provided to pregnant women under different implementations. Continuity is measured in terms of the percentage of occasions a team midwife will be available to meet the health care demands of pregnant women. The model may be used not only for the evaluation of services already in use, but also for the planning of alternative and better services.     

Thermosensitive hard spheres

We demonstrate an extension of a UV-Vis spectroscopy method to determine the phase boundaries for thermosensitive colloids as an alternative to the time-consuming sedimentation method. The Bragg attenuation peak from colloidal crystallites was monitored during the quasi-equilibrium colloidal crystal melting. The melting and freezing boundaries of the coexistence region were determined via a blue shift of Bragg's peak and the disappearance of peak area. We confirm this method using poly(N-isopropylacrylamide) (PNIPAM) particles at different charge densities and temperatures far below the lower critical solution temperature. At low pH, the particles behave as thermosensitive hard spheres.