Subventricular zone stem cells are heterogeneous with respect to their embryonic origins and neurogenic fates in the adult olfactory bulb

Wedetermined the embryonic origins of adult forebrain subventricular zone (SVZ) stem cells by Cre-lox fate mapping in transgenic mice. We found that all parts of the telencephalic neuroepithelium, including the medial ganglionic eminence and lateral ganglionic eminence (LGE) and the cerebral cortex, contribute multipotent, self-renewing stem cells to the adult SVZ. Descendants of the embryonic LGE and cortex settle in ventral and dorsal aspects of the dorsolateral SVZ, respectively. Both populations contribute new (5-bromo-2(')-deoxyuridine- labeled) tyrosine hydroxylase- and calretinin-positive interneurons to the adult olfactory bulb. However, calbindin-positive interneurons in the olfactory glomeruli were generated exclusively by LGE- derived stem cells. Thus, different SVZ stem cells have different embryonic origins, colonize different parts of the SVZ, and generate different neuronal progeny, suggesting that some aspects of embryonic patterning are preserved in the adult SVZ. This could have important implications for the design of endogenous stem cell-based therapies in the future

A fast and robust numerical scheme for solving models of charge carrier transport and ion vacancy motion in perovskite solar cells

Drift-diffusion models that account for the motion of both electronic and ionic charges are important tools for explaining the hysteretic behaviour and guiding the development of metal halide perovskite solar cells. Furnishing numerical solutions to such models for realistic operating conditions is challenging owing to the extreme values of some of the parameters. In particular, those characterising (i) the short Debye lengths (giving rise to rapid changes in the solutions across narrow layers), (ii) the relatively large potential differences across devices and (iii) the disparity in timescales between the motion of the electronic and ionic species give rise to significant stiffness. We present a finite difference scheme with an adaptive time step that is posed on a non-uniform staggered grid that provides second order accuracy in the mesh spacing. The method is able to cope with the stiffness of the system for realistic parameters values whilst providing high accuracy and maintaining modest computational costs. For example, a transient sweep of a current-voltage curve can be computed in only a few minutes on a standard desktop computer.Comment: 22 pages, 8 figure

High-speed multi-dimensional relative navigation for uncooperative space objects

This work proposes a high-speed Light Detection and Ranging (LIDAR) based navigation architecture that is appropriate for uncooperative relative space navigation applications. In contrast to current solutions that exploit 3D LIDAR data, our architecture transforms the odometry problem from the 3D space into multiple 2.5D ones and completes the odometry problem by utilizing a recursive filtering scheme. Trials evaluate several current state-of-the-art 2D keypoint detection and local feature description methods as well as recursive filtering techniques on a number of simulated but credible scenarios that involve a satellite model developed by Thales Alenia Space (France). Most appealing performance is attained by the 2D keypoint detector Good Features to Track (GFFT) combined with the feature descriptor KAZE, that are further combined with either the H∞ or the Kalman recursive filter. Experimental results demonstrate that compared to current algorithms, the GFTT/KAZE combination is highly appealing affording one order of magnitude more accurate odometry and a very low processing burden, which depending on the competitor method, may exceed one order of magnitude faster computation

Highly sensitive alkane odour sensors based on functionalised gold nanoparticles

We deposit dense, ordered, thin films of Au-dodecanethiol core/shell nanoparticles by the Langmuir-Schafer (LS) printing method, and find that their resistance at ambient temperature responds selectively and sensitively to alkane odours. Response is a rapid resistance increase due to swelling, and is strongest for alkane odours where the alkane chain is similar in length to the dodecane shell. For decane odours, we find a response to concentrations as low as 15 ppm, about 600 times below the lower explosive limit. Response is weaker, but still significant, to aromatic odours (e.g. Toluene, Xylene), while potential interferants such as polar and/or hydrogen-bonding odours (e.g. alcohols, ketones, water vapour) are somewhat rejected. Resistance is weakly dependent on temperature, and recovers rapidly and completely to its original value within the error margin of measurement. (C) 2011 Elsevier B.V. All rights reserved

The Bodily Movements of Liars

We measured the continuous bodily motion of participants as they lied to experimenters. These lies were spontaneous rather than elicited, and occurred for different motivations. In one situation, participants were given the opportunity to lie about their performance on a maths test in order to win money. In another, they witnessed one experimenter accidentally break a laptop. When asked what had happened, participants were motivated to lie and deny any knowledge. Across these situations, participants lied 61% of the time, allowing us to contrast the body movements of liars with truth tellers as they answered neutral and critical questions. Those who lied had significantly reduced bodily motion. In one case this motion appeared before the experimenter had even asked the critical question. We conclude that a person’s bodily dynamics can be indicative of their cognitive and effective states, even when they would rather conceal them

A new positioning framework for organisational value: juxtaposing organisational value positions with customer centricity

‘Value’ is worthy of study as it determines success for leaders, provides competitive advantage and contributes to economic prosperity. Indeed value may be a super-ordinate concept that has ‘upstaged’ previous research areas such as service quality, service satisfaction and relationship marketing. Many studies use ‘silo-based approaches’ when considering value, for example economic, socio-cultural and environmental value are often studied separately (Smith-Christensen, 2009). This study is inter-disciplinary being located in the overlap between strategic, customer-centric and value-laden disciplines. This paper provides insights by distilling extant ‘value’ themes. First, it critiques the plethora of value-types and complexities germane to value location. Then it holistically reflects on the distinct positions that have occupied value research to-date, namely ‘transactional’, ‘co-creation’ and ‘value-seeking’. There is much research into the first two but less on value-seeking. Furthermore little research exists on evaluating whether more than one organisational value position exists. Hence this paper posits that both distinct and overlapping positions may co-exist in organisations. These distinct and overlapping positions are juxtaposed with customer versus company-centric orientations to produce an original positioning framework that will be useful for practitioners and scholars alike. Finally the framework’s limitations are considered by using exemplars and analogies to promote better understanding

Will I? won't I? Why do men who have sex with men present for post-exposure prophylaxis for sexual exposures?

Background: Failures of post-exposure prophylaxis following sexual exposure (PEPSE) to prevent seroconversion have been reported and are often associated with ongoing risk exposure. Understanding why men who have sex with men (MSM) access PEPSE on some occasions and not others may lead to more effective health promotion and disease prevention strategies Methods: A qualitative study design using semi-structured interviews of 15 MSM within 6 months of them initiating PEPSE treatment at an HIV outpatient service in Brighton, UK. Results: PEPSE seeking was motivated by a number of factors: an episode that related to a particular sexual partner and their behaviour; the characteristics of the venue where the risk occurred; the respondent’s state of mind and influences of alcohol and recreational drug use; and their perceived beliefs on the effectiveness of PEPSE. Help was sought in the light of a “one-off” or “unusual” event. Many respondents felt they were less likely to behave in a risky manner following PEPSE. Conclusion: If PEPSE is to be effective as a public health measure, at risk individuals need to be empowered to make improved risk calculations from an increased perception that they could be exposed to HIV if they continue their current behaviour patterns. The concern is that PEPSE was sought by a low number of MSM implying that a greater number are not using the service based on failure to make accurate risk calculations or recognise high-risk scenario

ECMs and Institutional Repositories. The Case for a Unified Enterprise Approach to Content Management

Universities are currently developing responses to manage the explosion of research content. There is an expectation by these institutions as well as governments, funding agencies and other stakeholders that research data will be well managed, available and accessible to users as appropriate. The large enterprise content management (ECM) platform vendors are evolving into “information management frameworks”. The ECM solutions being marketed by these vendors are underpinned by content repositories, promising to manage all of the enterprise’s digital assets. One might logically question whether a university actually needs separate institutional repositories (IR) systems and infrastructure such as DSpace, for example, to manage research data. If these new enterprise solutions overcome the historical shortcomings traditionally associated with research content, then what is the future of the IR? The implementation of SharePoint along with new research data services at Griffith University has been a catalyst for beginning to question some of the fundamental paradigms which have underpinned the current thinking about an enterprise approach to research infrastructure and the role of research repositories. Having conducted a literature review, the authors outline the roles of enterprise content management systems and institutional repositories in the context of strategies, processes, and technologies rather than as single products. The focus is on architecture and a management approach rather than technological solutions. This paper explores the synergies between institutional repositories and enterprise content management systems and how research content would fit within the traditional enterprise content management system model. It concludes that there are major benefits in taking a unified enterprise approach to managing research content within a university

Scale robust IMU-assisted KLT for stereo visual odometry solution

We propose a novel stereo visual IMU-assisted (Inertial Measurement Unit) technique that extends to large inter-frame motion the use of KLT tracker (Kanade–Lucas–Tomasi). The constrained and coherent inter-frame motion acquired from the IMU is applied to detected features through homogenous transform using 3D geometry and stereoscopy properties. This predicts efficiently the projection of the optical flow in subsequent images. Accurate adaptive tracking windows limit tracking areas resulting in a minimum of lost features and also prevent tracking of dynamic objects. This new feature tracking approach is adopted as part of a fast and robust visual odometry algorithm based on double dogleg trust region method. Comparisons with gyro-aided KLT and variants approaches show that our technique is able to maintain minimum loss of features and low computational cost even on image sequences presenting important scale change. Visual odometry solution based on this IMU-assisted KLT gives more accurate result than INS/GPS solution for trajectory generation in certain context