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Catalytic combustion of volatile organic compounds (VOCs) over structured Co3O4 nano-flowers on silicalite-1/SiC foam catalysts
No full textThis work presents a simple method for the preparation of structured Co3O4 supported on silicalite-1/SiC foam catalyst (i.e., Co@S1/SiC), and its application to catalytic combustion of volatile organic compounds (VOCs, isopropanol as the model compound). The growth mechanism of Co3O4 on silicalite-1/SiC catalysts were systematically studied as a function of synthesis time based on comprehensive characterization using N2 adsorption-desorption analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), H2 temperature programmed reduction (H2-TPR) and X-ray photoelectron spectra (XPS). It was found that Co2SiO4 nano-sheets were formed within/on silicalite-1 coating at the initial stage of synthesis, which was further transformed into flower-like Co3O4 nano crystals on the surface of silicalite-1/SiC. The developed structured catalyst, especially the one prepared by the 40 h synthesis, i.e., Co@S1/SiC-40h, combined high oxygen mobility, Co3+/Co2+ redox couple and improved adsorbed oxygen species, and exhibited excellent performance in complete thermocatalytic combustion of isopropanol
Ocean Warming Impairs the Predator Avoidance Behaviour of Elasmobranch Embryos
No full textEmbryogenesis is a vulnerable stage in elasmobranch development due in part to high predation mortality. Embryonic elasmobranchs respond to potential predators by displaying a freezing behaviour, characterised by the cessation of pharyngeal respiration followed immediately by coiling of the tail around the body. We hypothesised that the duration of this freeze response is limited by the embryo’s requirement for oxygen. Here, Scyliorhinus canicula embryos were incubated at either 15˚C or 20˚C during embryogenesis and tested for the duration of, and metabolic response to, the freeze response at their respective incubation temperature. Freeze response duration was negatively impacted by routine metabolic rate; embryos at 20˚C had a 7-fold shorter freeze duration than those at 15˚C, potentially increasing their susceptibility to predation. These data demonstrate the capacity for climate change stressors to affect animal behaviour and suggest that this may occur by eliciting changes in the organism’s metabolism. We suggest altered predator avoidance behaviour is a new factor to consider when assessing the impact of climate change on the conservation and management of oviparous elasmobranch species
Diffusion of Globular Macromolecules in Liquid Crystals of Colloidal Cuboids
No full textMacromolecular diffusion in dense colloidal suspensions is an intriguing topic of interdisciplinary relevance in Science and Engineering. While significant efforts have been undertaken to establish the impact of crowding on the dynamics of macromolecules, less clear is the role played by long-range ordering. In this work, we perform Dynamic Monte Carlo simulations to assess the importance of ordered crowding on the diffusion of globular macromolecules, here modelled as spherical tracers, in suspensions of colloidal cuboids. We first investigate the diffusion of such guest tracers in very weakly ordered host phases of cuboids and, by increasing density above the isotropic-to-nematic phase boundary, study the influence of long-range orientational ordering imposed by the occurrence of liquid-crystalline phases. To this end, we analyse a spectrum of dynamical properties that clarify the existence of slow and fast tracers and the extent of deviations from Gaussian behaviour. Our results unveil the existence of randomly oriented clusters of cuboids that display a relatively large size in dense isotropic phases, but are basically absent in the nematic phase. We believe that these clusters are responsible for a pronounced non-Gaussian dynamics that is much weaker in the nematic phase, where orientational ordering smooths out such structural heterogeneities
Surveillance recommendations for DICER1 pathogenic variant carriers:A report from the SIOPE Host Genome Working Group and CanGene-CanVar Clinical Guideline Working Group
No full textDICER1 syndrome is a rare genetic disorder that predisposes to a wide spectrum of tumors. Developing surveillance protocols for this syndrome is challenging because uncertainty exists about the clinical efficacy of surveillance, and appraisal of potential benefits and harms vary. In addition, there is increasing evidence that germline DICER1 pathogenic variants are associated with lower penetrance for cancer than previously assumed. To address these issues and to harmonize DICER1 syndrome surveillance programs within Europe, the Host Genome Working Group of the European branch of the International Society of Pediatric Oncology (SIOPE HGWG) and Clinical Guideline Working Group of the CanGene-CanVar project in the United Kingdom reviewed current surveillance strategies and evaluated additional relevant literature. Consensus was achieved for a new surveillance protocol and information leaflet that informs patients about potential symptoms of DICER1-associated tumors. The surveillance protocol comprises a minimum program and an extended version for consideration. The key recommendations of the minimum program are: annual clinical examination from birth to age 20 years, six-monthly chest X-ray and renal ultrasound from birth to age 6 years, and thyroid ultrasound every 3 years from age 8 to age 40 years. The surveillance program for consideration comprises additional surveillance procedures, and recommendations for DICER1 pathogenic variant carriers outside the ages of the surveillance interval. Patients have to be supported in choosing the surveillance program that best meets their needs. Prospective evaluation of the efficacy and patient perspectives of proposed surveillance recommendations is required to expand the evidence base for DICER1 surveillance protocols
Drone Mobile Networks: Performance Analysis under 3D Tractable Mobility Models
No full textReliable wireless communication networks are a significant but challenging mission for post-disaster areas and hotspots in the era of information. However, with the maturity of unmanned aerial vehicle (UAV) technology, drone mobile networks have attracted considerable attention as a prominent solution for facilitating critical communications. This paper provides a system-level analysis for drone mobile networks ona finite three-dimensional (3D) space. Our aim is to explore the fundamental performance limits of drone mobile networks taking into account practical considerations. Most existing works on mobile drone networks use simplified mobility models (e.g., fixed height), but the movement of the drones in practice is significantly more complicated, which leads to difficulties in analyzing the performance of the drone mobile networks. Hence, to tackle this problem, we propose a stochastic geometry-based framework with a number of different mobility models including a randomBrownian motion approach. The proposed framework allows to circumvent the extremely complex reality model and obtain upper and lower performance bounds for drone networks in practice. Also, we explicitly consider certain constraints, such as the smallscale fading characteristics relying on line-of-sight (LOS) and non line-of-sight (NLOS) propagation, and multi-antenna operations. The validity of the mathematical findings is verified via Monte-Carlo (MC) simulations for various network settings. In addition, the results reveal some design guidelines and important trends for the practical deployment of drone networks
DEATHSTAR: Nearby AGB stars with the Atacama Compact Array II. CO envelope sizes and asymmetries:The S-type stars
No full textAims.We aim to constrain the sizes of, and investigate deviations from spherical symmetry in, the CO circumstellar envelopes (CSEs)of 16 S-type stars, along with an additional 7 and 4 CSEs of C-type and M-type AGB stars, respectively.Methods. We map the emission from the CO J = 2–1 and 3–2 lines observed with the Atacama Compact Array (ACA) and its totalpower (TP) antennas, and fit with a Gaussian distribution in the uv- and image planes for ACA-only and TP observations, respectively.The major axis of the fitted Gaussian for the CO(2–1) line data gives a first estimate of the size of the CO-line-emitting CSE. Weinvestigate possible signs of deviation from spherical symmetry by analysing the line profiles, the minor/major axes ratio obtainedfrom visibility fitting, and by investigating the deconvolved images.Results. The sizes of the CO-line-emitting CSEs of low-mass-loss-rate (low-MLR) S-type stars fall between the sizes of C-stars,which are larger, and M-stars, which are smaller, as expected due to the dierences in their respective CO abundances and thedependence of the photodissociation rate on this quantity. The sizes of the low-MLR S-type stars show no dependence on circumstellardensity, as measured by the ratio of the MLR to terminal outflow velocity, irrespective of variability type. The density dependencesteepens for S-stars with higher MLRs. While the CO(2–1) brightness distribution size of the low-density S-stars is in general smallerthan the predicted photodissociation radius (assuming the standard interstellar radiation field), the measured size of a few of the highdensitysources are of the same order as the expected photodissociation radius. Furthermore, our results show that the CO CSEs ofmost of the S-stars in our sample are consistent with a spherically symmetric and smooth outflow. For some of the sources, clear andprominent asymmetric features are observed which are indicative of intrinsic circumstellar anisotropy.Conclusions. As the majority of the S-type CSEs of the stars in our sample are consistent with a spherical geometry, the CO envelopesizes obtained in this paper will be used to constrain detailed radiative transfer modelling to directly determine more accurate MLRestimates for the stars in our sample. For several of our sources that present signs of deviation from spherical symmetry, further highresolution observations would be necessary to investigate the nature and the physical processes behind these asymmetrical structures.This will provide further insight into the mass-loss process and its related chemistry of S-type AGB stars
Examining the experiences and support needs of bereaved parents following the death of a child during early adulthood from cancer.
No full textBackgroundFollowing a child’s death from cancer, parents experience a unique grief which may be experienced differently by mothers and fathers. However, there is a lack of knowledge about the particular bereavement experiences of the parents of young adults and their support needs.ObjectiveThe aim of the study was to investigate the bereavement experiences and support needs of parents following the death of a child (aged 16 29 years old) from cancer and explore how these change over time.MethodsThe study used a Charmazian constructivist grounded theory ( approach. Semi structured interviews were conducted with 11 parents (seven mothers, four fathers) who were purposefully sampled from one specialist cancer centre and who had been bereaved for between 15 months and7 years. Data were analysed inductively using the constant comparative approach with initial and focused coding for category development and core category identification.Results‘Living with continual loss’ emerged as the core category which was central to parents’ experiences of bereavement. Feelings of continual loss were compounded by parents’ lack of information about bereavement (‘grieving in the dark’) and a perceived lack of understanding and support from families and friend s (‘grieving alone’). Nevertheless, parents discovered strategies to help them manage living with continual loss (‘changing routines’, ‘preserving the meaning of home’, ‘maintaining memories and presence’ and ‘sharing experiences’).ConclusionsThis is the first study focusing on the experiences and support needs of bereaved parents of young adults who have died from cancer. It has revealed that parents lived with a continual sense of loss irrespective of the length of bereavement. While they dev eloped strategies over time tomanage this loss, they experienced a lack of information and empathetic emotional support
Inflammatory arthropathy in the elite sports athlete
No full textElite athletes commonly present with joint pains that are attributed to overuse injuries though on occasion it can be due to an inflammatory arthropathy. The diagnostic challenge is that presenting symptoms of benign injuries are similar to inflammatory arthropathies. A holistic review of the athlete can provide clues suggestive of inflammatory arthropathy, before requesting further investigations to confirm the diagnosis. Current imaging modalities are not specific in differentiating inflammatory arthritis with other causes of joint inflammation. Prompt treatment is required to restore the athlete to an optimum level of activity and prevent career ending disability, all in adherence to the regulations of the sporting governing bodies. This review aims to highlight the importance of inflammatory arthropathy in the differentials for an athlete presenting with joint pains
A de novo Synthesis of Oxindoles from Cyclohexanone-Derived γ-Keto-ester Acceptors Using a Desaturative Amination–Cyclization Approach
No full textHere we report a desaturative approach for oxindole synthesis. This method uses simple γ-ester-containing cyclohexanones and primary amine building blocks as coupling partners. A dual photoredox–cobalt manifold is used to generate a secondary aniline that, upon heating, cyclizes with the pendent ester functionality. The process operates under mild conditions and was applied to the modification of several amino acids, the blockbuster drug mexiletine, as well as the formation of dihydroquinolinones