Electrochemical detection of TNT at cobalt phthalocyanine mediated screen-printed electrodes and application to detection of airborne vapours

We describe the use of cobalt phthalocyanine as a mediator to improve the sensitivity for the electrochemical detection of TNT. Commercial screen-printed electrodes containing cobalt phthalocyanine were employed for determination of TNT. Improved sensitivities compared to screen-printed carbon electrodes without phthalocyanine were observed, current response for cyclic voltammetric measurements at modified electrodes being at least double that of unmodified electrodes. A synergistic effect between oxygen and TNT reduction was also observed. Correlation between TNT concentrations and sensor output was observed between 0–200 µM TNT. Initial proof-of-concept experiments combining electrochemical determinations, with the use of an air-sampling cyclone, are also reported

Research on physical and physiological aspects of visual optics in space flight

Physical and physiological aspects of visual optics in space fligh

On the Fokker-Planck approximation to the Boltzmann collision operator

The Boltzmann equation (BE) is a mesoscopic model that provides a description of how gases undergoing a binary collision process evolve in time, however there is no general analytical approach for finding its solutions and direct numerical treatment using quadrature methods is prohibitively expensive due to the dimensions of the problem. For this reason, models that are able to capture the behaviour of solutions to the BE, but which are simpler to treat numerically and analytically are highly desirable. The Fokker-Planck collision operator is one such collision model, which is suited well to numerical solutions using stochastic particle methods, and is the subject of this thesis. The stochastic numerical solutions of the Fokker-Planck model suffer heavily from noise when the speed of the flow is low. We develop two methods that are able to reduced the variance of the estimators of the particle method. The first is a common random number method, which produces a correlated equilibrium solution where thermodynamic fields are known. The second is a importance sampling method, where weights are attached to the particles. This means that particles close to equilibrium do not contribute to the noise of the estimators. We also develop a randomised quasi-Monte Carlo scheme for solving the diffusion equation, which has a faster rate of convergence than simple Monte Carlo methods. The relative simplicity of the functional form of the Fokker-Planck collision operator makes it possible to find analytic solutions in simple cases. We consider a spatially homogeneous, isotropic gas with elastic collisions in the presence of forcing and dissipation and derive self-consistent non-equilibrium steady-state solutions. Previous numerical evidence exists that suggest such forcing and dissipation mechanisms, widely separated, give rise to steady-states of the BE that are close to Maxwellian, with a direct energy cascade and an inverse particle cascade. Using our analytic solutions, we are able to investigate the dependence of such solutions on the forcing and dissipation scales, and find that in the inertial range, the interaction is non-local. We then show that the “extreme driving” mechanism, responsible for a family of non-universal power-law solutions for inelastic granular gases, where the flux of energy is towards lower scales, is also able to produce inverse energy cascades for the elastic system

Mii-vitaliSe: a pilot randomised controlled trial of a home gaming system (Nintendo Wii) to increase activity levels, vitality and well-being in people with multiple sclerosis.

OBJECTIVES: While the health and well-being benefits of physical activity are recognised, people with multiple sclerosis (MS) often face greater barriers than the general population. The Nintendo Wii potentially offers a fun, convenient way of overcoming some of these. The aim was to test the feasibility of conducting a definitive trial of the effectiveness and cost-effectiveness of Mii-vitaliSe; a home-based, physiotherapist-supported Nintendo Wii intervention. DESIGN: A single-centre wait-list randomised controlled study. SETTING: MS service in secondary care. PARTICIPANTS: Ambulatory, relatively inactive people with clinically confirmed MS. INTERVENTION: Thirty participants were randomised to receive Mii-vitaliSe either immediately (for 12 months) or after a 6-month wait (for 6 months). Mii-vitaliSe consisted of two supervised Nintendo Wii familiarisation sessions in the hospital followed by home use (Wii Sports, Sports Resort and Fit Plus software) with physiotherapist support and personalised resources. OUTCOMES: Included self-reported physical activity levels, quality of life, mood, self-efficacy, fatigue and assessments of balance, gait, mobility and hand dexterity at baseline, 6 and 12 months. Interviews (n=25) explored participants' experiences and, at study end, the two Mii-vitaliSe facilitators' experiences of intervention delivery (main qualitative findings reported separately). RESULTS: Mean (SD) age was 49.3 (8.7) years, 90% female, with 47% diagnosed with MS <6 years ago and 60% new to active gaming. The recruitment rate was 31% (95% CI 20% to 44%). Outcome data were available for 29 (97%) at 6 months and 28 (93%) at 12 months. No serious adverse events were reported during the study. Qualitative data indicated that Mii-vitaliSe was well-received. Mean Wii use across both groups over the initial 6-month intervention period was twice a week for 27 min/day. Mean cost of delivering Mii-vitaliSe was £684 per person. DISCUSSION: Mii-vitaliSe appears acceptable and a future trial feasible and warranted. These findings will inform its design. TRIAL REGISTRATION: ISRCTN49286846

Postmetamorphic ontogenetic allometry and the evolution of skull shape in Nest-building frogs Leptodactylus (Anura: Leptodactylidae)

Allometry constitutes an important source of morphological variation. However, its influence in head development in anurans has been poorly explored. By using geometric morphometrics followed by statistical and comparative methods we analyzed patterns of allometric change during cranial postmetamorphic ontogeny in species of Nest-building frogs Leptodactylus (Leptodactylidae). We found that the anuran skull is not a static structure, and allometry plays an important role in defining its shape in this group. Similar to other groups with biphasic life-cycle, and following a general trend in vertebrates, ontogenetic changes mostly involve rearrangement in rostral, otoccipital, and suspensorium regions. Ontogenetic transformations are paralleled by shape changes associated with evolutionary change in size, such that the skulls of species of different intrageneric groups are scaled to each other, and small and large species show patterns of paedomorphic/peramorphic features, respectively. Allometric trajectories producing those phenotypes are highly evolvable though, with shape change direction and magnitude varying widely among clades, and irrespective of changes in absolute body size. These results reinforce the importance of large-scale comparisons of growth patterns to understand the plasticity, evolution, and polarity of morphological changes in different clades.Fil: Duport Bru, Ana Sofía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Ponssa, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Vera Candioti, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

Exploring the presentation of Black autistic characters in children's picture books

In 2019, 441 children’s and young adult’s books were published that featured a Black person as a primary character representing 11.9% of all children’s books published (CCBC, 2020). Similarly, representations of autistic characters in children’s books remain rare and disproportionate to the demographic (Azano, Tackett, & Sigmon, 2017). Indeed, books that contain a Black, autistic character remain even rarer. This presentation explores the initial stages of a project that examines the representation of Black autistic characters in children’s picture books. It samples four children’s books with a main character who is Black and autistic, exploring the representation of their Blackness and their autism. This project is predicated on the concept of books as mirrors (Bishop, 1990), with smaller mirrors showing smaller and more imperfect reflections. Whilst white, neurotypical children have a variety of different versions of themselves represented in fiction, the underrepresentation of Black autistic characters in children’s books means that Black, autistic students may arrive at university having never seen characters they can identify with represented sufficiently. This has implications for educators and learning support departments in HE who may be able to use our findings to better understand Black autistic students’ experience prior to arriving at university and tailor their provision accordingly

Contemporary Evolutionary Divergence for a Protected Species following Assisted Colonization

Contemporary evolution following assisted colonization may increase the probability of persistence for refuge populations established as a bet-hedge for protected species. Such refuge populations are considered "genetic replicates" that might be used for future re-colonization in the event of a catastrophe in the native site. Although maladaptive evolutionary divergence of captive populations is well recognized, evolutionary divergence of wild refuge populations may also occur on contemporary time scales. Thus, refuge populations may lose their "value" as true genetic replicates of the native population. Here, we show contemporary evolutionary divergence in body shape in an approximately 30-year old refuge population of the protected White Sands pupfish (Cyprinodon tularosa) resulting in a body-shape mismatch with its native environment.Geometric morphometic data were collected from C. tularosa cultures raised in experimental mesocosms. Cultures were initiated with fish from the two native populations, plus hybrids, in high or low salinity treatments representing the salinities of the two native habitats. We found that body shape was heritable and that shape variation due to phenotypic plasticity was small compared to shape variation due to population source. C. tularosa from the high salinity population retained slender body shapes and fish from the low salinity population retained deep body shapes, irrespective of mesocosm salinity. These data suggest that the observed divergence of a recently established pupfish population was not explained by plasticity. An analysis of microsatellite variation indicated that no significant genetic drift occurred in the refuge population, further supporting the adaptive nature of changes in body shape. These lines of evidence suggest that body shape divergence of the refuge population reflects a case of contemporary evolution (over a 30-year period).These results suggest assisted colonization can introduce novel, and/or relaxed selection, and lead to unintended evolutionary divergence

Phenotypic Plasticity and Contemporary Evolution in Introduced Populations: Evidence from Translocated Populations of White Sands Pupfish (Cyrpinodon tularosa)

Contemporary evolution has been shown in a few studies to be an important component of colonization ability, but seldom have researchers considered whether phenotypic plasticity facilitates directional evolution from the invasion event. In the current study, we evaluated body shape divergence of the New Mexico State-threatened White Sands pupfish (Cyprinodon tularosa) that were introduced to brackish, lacustrine habitats at two different time in the recent past (approximately 30 years and 1 year previously) from the same source population (saline river environment). Pupfish body shape is correlated with environmental salinity: fish from saline habitats are characterized by slender body shapes, whereas fish from fresher, yet brackish springs are deep-bodied. In this study, lacustrine populations consisted of an approximately 30-year old population and several 1-year old populations, all introduced from the same source. The body shape divergence of the 30-year old population was significant and greater than any of the divergences of the 1-year old populations (which were for the most part not significant). Nonetheless, all body shape changes exhibited body deepening in less saline environments. We conclude that phenotypic plasticity potentially facilitates directional evolution of body deepening for introduced pupfish populations