Generation of three-dimensional multiple spheroid model of olfactory ensheathing cells using floating liquid marbles

We describe a novel protocol for three-dimensional culturing of olfactory ensheathing cells (OECs), which can be used to understand how OECs interact with other cells in three dimensions. Transplantation of OECs is being trialled for repair of the paralysed spinal cord, with promising but variable results and thus the therapy needs improving. To date, studies of OEC behaviour in a multicellular environment have been hampered by the lack of suitable three-dimensional cell culture models. Here, we exploit the floating liquid marble, a liquid droplet coated with hydrophobic powder and placed on a liquid bath. The presence of the liquid bath increases the humidity and minimises the effect of evaporation. Floating liquid marbles allow the OECs to freely associate and interact to produce OEC spheroids with uniform shapes and sizes. In contrast, a sessile liquid marble on a solid surface suffers from evaporation and the cells aggregate with irregular shapes. We used floating liquid marbles to co-culture OECs with Schwann cells and astrocytes which formed natural structures without the confines of gels or bounding layers. This protocol can be used to determine how OECs and other cell types associate and interact while forming complex cell structuresJSJ was funded by a grant from the Perry Cross Spinal Research Foundation; NTN was funded from Griffith University through a start-up grant and a grant from the Griffith University Research Infrastructure Program; JAK was funded by an Australian Research Council Discovery Grant DP150104495; JT was funded by an Eskitis Institute scholarship; CO was funded by a Griffith Sciences scholarship; RV was funded by a Griffith University International Postgraduate Research Scholarshi

SEU Rate in 90nm and 180nm of 6T SRAM at NEqO Orbit

RazakSat® was a remote sensing satellite which functioned as to acquire the information from the earth surface. RazakSat® was launched to low altitudes, around 600km above the earth surface in 2009.  Although RazakSat® was a low altitude satellite but the malfunction of the RazakSat® was suspected experienced high rates of anomalies. The main factor of getting high rates of anomalies is due to the RazakSat® was exposed to space radiation environment when the satellite passed through the South Atlantic region at its NEqO trajectory. An investigation was carried out to predict the Single Event Upset (SEU) rate for 6T SRAM, which is located at On-Board Computer (OBC) of the satellite. The results show that the Q node in 6T SRAM is the most sensitive node and this node becomes the main focus in this paper in order to estimate direct ionisation induced SEU rates in the worst case scenario. Apart from that, the comparison by using 90nm and 180nm of 6T SRAM are shown whereby with 90nm, around 1083.5 error/bit day is occurred and there is around 4.538 errors/bit day is found by using 180nm of the 6T SRAM

Supervised and Unsupervised Detections for Multiple Object Tracking in Traffic Scenes: A Comparative Study

In this paper, we propose a multiple object tracker, called MF-Tracker, that integrates multiple classical features (spatial distances and colours) and modern features (detection labels and re-identification features) in its tracking framework. Since our tracker can work with detections coming either from unsupervised and supervised object detectors, we also investigated the impact of supervised and unsupervised detection inputs in our method and for tracking road users in general. We also compared our results with existing methods that were applied on the UA-Detrac and the UrbanTracker datasets. Results show that our proposed method is performing very well in both datasets with different inputs (MOTA ranging from 0:3491 to 0:5805 for unsupervised inputs on the UrbanTracker dataset and an average MOTA of 0:7638 for supervised inputs on the UA Detrac dataset) under different circumstances. A well-trained supervised object detector can give better results in challenging scenarios. However, in simpler scenarios, if good training data is not available, unsupervised method can perform well and can be a good alternative.Comment: Accepted for ICIAR 202

Molecular determinants of plaque size as an indicator of dengue virus attenuation

The development of live viral vaccines relies on empirically derived phenotypic criteria, especially small plaque sizes, to indicate attenuation. However, while some candidate vaccines successfully translated into licensed applications, others have failed safety trials, placing vaccine development on a hit-or-miss trajectory. We examined the determinants of small plaque phenotype in two dengue virus (DENV) vaccine candidates, DENV-3 PGMK30FRhL3, which produced acute febrile illness in vaccine recipients, and DENV-2 PDK53, which has a good clinical safety profile. The reasons behind the failure of PGMK30FRhL3 during phase 1 clinical trial, despite meeting the empirically derived criteria of attenuation, have never been systematically investigated. Using in vitro, in vivo and functional genomics approaches, we examined infections by the vaccine and wild-type DENVs, in order to ascertain the different determinants of plaque size. We show that PGMK30FRhL3 produces small plaques on BHK-21 cells due to its slow in vitro growth rate. In contrast, PDK53 replicates rapidly, but is unable to evade antiviral responses that constrain its spread hence also giving rise to small plaques. Therefore, at least two different molecular mechanisms govern the plaque phenotype; determining which mechanism operates to constrain plaque size may be more informative on the safety of live-attenuated vaccines

Sponsor ownership in Asian REITs

This study examines the relationship between sponsor ownership and firm performance proxied by firm value, operating cash flow, and dividend policy with Asian real estate investment trusts (REITs) in Japan, Hong Kong, Malaysia, and Singapore for the period from 2002 to 2012, focusing on both the incentive alignment effect and the entrenchment effect. Our study sheds new light on effective corporate governance for Asian REITs that are prone to agency problems. Such agency problems arise from the inequitable distribution of power to sponsors that results from the external management structure. The findings suggest that larger sponsor ownership aligns the interests of sponsors and minority shareholders and enhances the performance of Asian REITs, while such an effect diminishes as sponsors become more entrenched. We find that the incentive alignment effect and entrenchment effect are primarily driven by developer-sponsored REITs. Also evident is that the presence of institutional investors mitigates agency problems and increases firm performance

Effects of adding natural sounds to urban noises on the perceived loudness of noise and soundscape quality

Introducing pleasant natural sounds to mask urban noises is an important soundscape design strategy to improve acoustic comfort. This study investigates the effects of signal-to-noise ratio (SNR) between natural sounds (signal) and the target noises (noise) and their temporal characteristics on the perceived loudness of noise (PLN) and overall soundscape quality (OSQ) through a laboratory experiment. Two types of urban noise sources (hydraulic breaker and traffic noises) were set to A-weighted equivalent sound pressure levels (SPL) of 55, 65, and 75 dB and then augmented with two types of natural sounds (birdsong and stream), across a range of SNRs. Each acoustic stimulus was a combination of noise and natural sound at SNRs from −6 to 6 dB. Averaged across all cases, the subjective assessment of PLN showed that augmenting urban noise separately with the two natural sounds reduced the PLN by 17.9%, with no significant differences found between the birdsong and stream sounds. Adding natural sounds increased the OSQ by on average 18.3% across the cases, but their effects gradually decreased as the noise level increased. The OSQ of the birdsong and stream sounds were similar for traffic noise, whereas the stream sound was rated higher than the birdsong for the breaker noise. The results suggest that increasing the dissimilarity in temporal structure between the target noise and natural sounds could enhance the soundscape quality. Appropriate SNRs were explored considering both PLN and OSQ. The results showed that the SNR of −6 dB was desirable when the A-weighted SPL of the noise rose to 75 dB

A mixed-reality approach to soundscape assessment of outdoor urban environments augmented with natural sounds

To investigate the effect of augmenting natural sounds in noisy environments, an in-situ experiment was conducted using a mixed-reality head-mounted display (MR HMD). Two outdoor locations close to an expressway were selected for the experiment. A natural sound (birdsong or stream) along with a hologram (sparrow/fountain or loudspeaker) was projected through the MR HMD. Participants were asked to adjust the natural sound levels to their preferred level under ambient traffic noise conditions at each location. Participants also assessed the perceived loudness of traffic (PLN) and overall soundscape quality (OSQ) in conditions with and without the augmented natural sounds. The results showed that both natural sounds significantly reduced the PLN and enhanced the OSQ. No significant differences in subjective responses were found between the loudspeaker and visual representations of the natural sound source as holograms. Analysis on the preferred signal-to-noise ratio (SNR), i.e. ratio of natural sound to traffic levels, indicated a strong negative correlation between the preferred SNRs and ambient traffic noise levels. Overall, the preferred SNR of the birdsong was significantly higher than that of the water sound. Among the acoustic parameters tested, the A-weighted traffic noise level was the strongest predictor for the preferred SNR of both the birdsong and water sound. However, the correlation for the water sound was relatively higher than the birdsong. This was due to the larger variance in the subjective evaluation for the birdsong

Effects of contexts in urban residential areas on the pleasantness and appropriateness of natural sounds

Before introducing natural sounds to potentially improve the soundscape quality, it is important to understand how key contextual factors (i.e. expected activities and audio-visual congruency) affect the soundscape in a given location. In this study, the perception of eight natural sounds (i.e. 4 birdsongs, 4 water sounds) at five urban recreational areas under the constant influence of road traffic was explored subjectively under three laboratory settings: visual-only, audio-only, and audio-visual. Firstly, expected socio-recreational activities of each location were determined in the visual-only setting. Subsequently, participants assessed the pleasantness and appropriateness of the soundscape at each site, for each of the eight natural sounds augmented to the same road traffic noise, in both audio-only and audio-visual settings. Interestingly, it was found that the expected activities in each location did not significantly affect natural sound perception, whereas audio-visual congruency of the locations significantly affected the pleasantness and appropriateness of the natural sounds. Particularly, the pleasantness and appropriateness decreased for water sounds when water features were not visually present. In contrast, perception with birdsongs was unaffected by their visibility likely due to the presence of vegetation. Hence, audio-visual coherence is central to the perception of natural sounds in outdoor spaces

Retroperitoneal liposarcomas: The experience of a tertiary Asian center

10.1186/1477-7819-9-12World Journal of Surgical Oncology9

Serum Metabolome and Lipidome Changes in Adult Patients with Primary Dengue Infection

10.1371/journal.pntd.0002373PLoS Neglected Tropical Diseases78