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Chemical looping combustion for coupling with efficient CO<sub>2 </sub>capture and utilization: stable oxygen carriers and carbon cycle
No full textThe capture of CO2 with chemical looping combustion (CLC) offers a novel approach to significantly reduce carbon emissions while simultaneously utilizing captured CO2 as a valuable resource by leveraging its inherent CO2 separation capability. The separation of CO2 in CLC technology achieves low-cost CO2 capture through the utilization of highly efficient oxygen carriers (OC), enabling the coupling of CO2 capture with subsequent hydrogenation reactions for high-value-added chemical production. This review comprehensively summarizes the principle of the CLC technology, the current status of OC research, and the potential for CO2 capture in chemical synthesis, providing theoretical insights into the feasibility of activating and utilizing CO2 within practical industrial processes. The stable OC brought about excellent properties and higher application value in the long term operation. The careful selection of a stable OC and the rational design of oxygen vacancies are the keys to enable this technology; however, further research is needed to develop a highly efficient and stable OC to optimize the CO2 capture efficiency and product yields while elucidating the underlying reaction mechanisms.</p
Stable laser-acceleration of high-flux proton beams with plasma collimation
No full textLaser-plasma acceleration of protons offers a compact, ultra-fast alternative to conventional acceleration techniques, and is being widely pursued for potential applications in medicine, industry and fundamental science. Creating a stable, collimated beam of protons at high repetition rates presents a key challenge. Here, we demonstrate the generation of multi-MeV proton beams from a fast-replenishing ambient-temperature liquid sheet. The beam has an unprecedentedly low divergence of 1° (≤20 mrad), resulting from magnetic self-guiding of the proton beam during propagation through a low density vapour. The proton beams, generated at a repetition rate of 5 Hz using only 190 mJ of laser energy, exhibit a hundred-fold increase in flux compared to beams from a solid target. Coupled with the high shot-to-shot stability of this source, this represents a crucial step towards applications.<br/
A novel method for subgroup discovery in precision medicine based on topological data analysis
No full textBackgroundThe Mapper algorithm is a data mining topological tool that can help us to obtain higher level understanding of disease by visualising the structure of patient data as a similarity graph. It has been successfully applied for exploratory analysis of cancer data in the past, delivering several significant subgroup discoveries. Using the Mapper algorithm in practice requires setting up multiple parameters. The graph then needs to be manually analysed according to a research question at hand. It has been highlighted in the literature that Mapper’s parameters have significant impact on the output graph shape and there is no established way to select their optimal values. Hence while using the Mapper algorithm, different parameter values and consequently different output graphs need to be studied. This prevents routine application of the Mapper algorithm in real world settings.MethodsWe propose a new algorithm for subgroup discovery within the Mapper graph. We refer to the task as hotspot detection as it is designed to identify homogenous and geometrically compact subsets of patients, which are distinct with respect to their clinical or molecular profiles (e.g. survival). Furthermore, we propose to include the existence of a hotspot as a criterion while searching the parameter space, addressing one of the key limitations of the Mapper algorithm (i.e. parameter selection).ResultsTwo experiments were performed to demonstrate the efficacy of the algorithm, including an artificial hotspot in the Two Circles dataset and a real world case study of subgroup discovery in oestrogen receptor-positive breast cancer. Our hotspot detection algorithm successfully identified graphs containing homogenous communities of nodes within the Two Circles dataset. When applied to gene expression data of ER+ breast cancer patients, appropriate parameters were identified to generate a Mapper graph revealing a hotspot of ER+ patients with poor prognosis and characteristic patterns of gene expression. This was subsequently confirmed in an independent breast cancer dataset.ConclusionsOur proposed method can be effectively applied for subgroup discovery with pathology data. It allows us to find optimal parameters of the Mapper algorithm, bridging the gap between its potential and the translational research.<br/
Chinese development finance and African policy space: towards productive incoherence?
No full textHow does Chinese Development Finance influence perceptions of policy space across Sub-Saharan Africa? This paper employs Grabel's concept of ‘productive incoherence’ to both describe the ‘new development finance landscape’ and to explore its implications for recipient-country policy space. Drawing on an exploratory survey of elite perceptions and three country case studies (Ethiopia, Malawi and Mozambique), we find that Chinese Development Finance contributes to incremental and context-specific enhancements in policy space, rather than transformative or wholesale change. Moreover, we contend that the extent of policy space is determined more-so by the internal dynamics, historical legacies and structural position of recipient countries within the global political economy, and the interplay between these elements, than by changes in the external financing environment.<br/
Developing appropriate environmental enrichment strategies for broiler breeders
No full textThere is a recognised need for environmental enrichment strategies to be developed for broiler parent stock. We evaluated the use and tested preferences for three forms of enrichment in commercial broiler breeder housing: (1) perches (platform perches, round metal perches, round rubber-coated metal perches), (2) pecking enrichments (silver reflective gazing balls, multi-coloured reflective gazing balls, non-reflective gazing balls), and (3) dust baths (oat hulls, sawdust, 50:50 mix). Observations from video footage were conducted during early, peak and late lay of a 44 week production phase on one farm. There was a clear preference for platform perches over both round perches, and for rubber-coated perches over metal perches until late lay. Perching was highest at night but reduced over the cycle. We found a drop off in perching once 23 cm of linear space per bird had been reached, suggesting this represented comfortable maximum capacity. All pecking enrichments attracted interest, with no difference between the three types, although pecking rate reduced across the cycle. House litter was well maintained and dustbathing was widely observed throughout the house, making additional dustbathing areas largely superfluous on this farm. We suggest platform perches and suspended gazing balls to be suitable environmental enrichments for commercial breeder housing.<br/
Chemical- and photo-activation of protein-protein thiol-ene coupling for protein profiling
No full textThe thiol-ene reaction between an alkene and a thiol can be exploited for selective labelling of cysteine residues in protein profiling applications. Here, we explore thiol-ene activation in systems from chemical models to complex cellular milieus, using UV, visible wavelength and redox initiators. Initial studies in chemical models required an oxygen-free environment for efficient coupling and showed very poor activation when using a redox initiator. When thiol-ene activation was performed in protein and cell lysate models, all three initiation methods were successful. Faster thiol-ene reaction was observed as the cysteine and alkene were brought into proximity by a binding event prior to activation, leading to quicker adduct formation in the protein model system than the chemical models. Furthermore, in the protein-protein coupling, none of the activators required an oxygen-free environment. Taken together, these observations demonstrate the broad potential for thiol-ene coupling to be used in protein profiling
IoV-TwinChain: Predictive maintenance of vehicles in internet of vehicles through digital twin and blockchain
No full textVehicular networks are experiencing a significant transformation driven by integrating connected vehicles and Intelligent Transportation Systems (ITS). The Internet of Vehicles (IoV) is a rapidly evolving domain within ITS that connects vehicles, infrastructure, and smart devices to facilitate seamless data exchange. This data encompasses vital information, and by leveraging it, vehicles can make informed decisions and adapt to real-time situations. For instance, traditional vehicle maintenance practices often rely on reactive approaches, addressing issues after failures occur, which can lead to safety risks, costly repairs, and disruptions. Thus, there is a pressing need for proactive solutions to identify vehicle failures before they escalate. Accordingly, we propose the IoV-TwinChain framework integrating Digital Twin (DT), Machine Learning (ML), and blockchain for performing predictive maintenance of vehicles in the IoV by monitoring vehicle operating conditions to prevent road breakdowns and failures. DT provides real-time monitoring of vehicle operating conditions, while ML facilitates data-driven predictions for the predictive maintenance of vehicles. The IoV-TwinChain framework utilizes blockchain for data integrity and traceability within physical and twin environments. We implement a Proof of Concept (PoC) of the IoV-TwinChain framework using Microsoft Azure DT, ML models such as Random Forest and XGBoost, and Ethereum blockchain. Additionally, we formally verify the IoV-TwinChain framework correctness using High-Level Petri Nets and Bounded Model-Checking methods. With our PoC implementation and formal verification, we demonstrate that the IoV-TwinChain framework effectively enhances the predictive maintenance capabilities of vehicles in the IoV and ensures the reliability and accuracy of the system.</p
Estudio De La Vida Bajo Estres: methodological overview and baseline data analysis of a case-control investigation of risk and resiliency factors for traumatic stress in Colombia
No full textThe Estudio de la Vida Bajo Estres (My Life Under Stress [MI-VIDA] Study) aims to investigate risk and resilience factors associated with the development of PTSD in a trauma-exposed sample of more than 500 Colombian residents exposed to this country’s armed conflict. The study utilised a longitudinal case-control design capturing psychosocial data over 18 months, in addition to baseline DNA samples for a parallel genomic analysis. This paper specifically provides an overview of the design and methodology of the wider investigation, and reports baseline characteristics including sociodemographic information and mental health outcome prevalences from this hard-to-reach and under-researched population. Results of baseline analysis suggested that one third (34.88%) of this trauma-exposed sample screened positively for PTSD. Participants endorsed high numbers of potentially traumatic experiences including Forced Displacement (88.61%), Exposure to Severe Human Suffering (53.91%), Combat Exposure (53.02%), and Physical Assault (51.78%). Participants also reported relatively high levels of mental ill-health including depression (29.90%) and anxiety (27.56%). The number of traumas experienced, and the reported comorbid difficulties were generally higher among those who screened positive for PTSD. These preliminary analyses detail the baseline characteristics, and the relative burden of mental ill-health in this trauma-exposed sample. The wider study comprising longitudinal measurement of these conditions has the potential to make a significant contribution to the understanding of risk and resiliency factors for posttraumatic stress in this unique Latin American context.<br/
Far-right movements in the Western world: How media exposure relates to normative beliefs and attitudes toward the far-right
No full textConsidering the rise of far-right groups in Western countries, we examined whether exposure to media coverage on the far-right is associated with attitudes toward it, using surveys in 15 Western democratic countries (total N = 2,576). We hypothesized that greater media exposure to the far-right will be associated with greater perceived prevalence and acceptability of it, which will in turn be associated with divergent attitudes. On the one hand, greater perceived prevalence may be associated with more unfavorable attitudes toward the far-right (a threat response). On the other hand, greater perceived acceptability may be associated with more favorable attitudes toward the far-right (a normalization response). Overall, there was more evidence for a threat response than a normalization response: media exposure was consistently related to greater perceived prevalence (but not acceptability) of the far-right. This research underscores the importance of studying the consequences of the rise of the far-right
Developing a conceptual model for collective patterns and leisure-time physical activity inequalities amongst adults
No full textBackground: Despite extensive efforts to tackle the unequal levels of leisure-time physical activity (LTPA) among adults, our understanding of how these inequalities are sustained over time is minimal. Existing approaches often overlook the complex dynamic, and typically nonlinear interactions, which shape physical activity patterns. Therefore, this paper aims to capture these dynamic interactions and processes which influence an individual’s decision to practice LTPA, with a specific focus on the influence of income. Methods: The conceptual model was developed in 4 main stages: (1) initial draft development, (2) realist reviews, (3) expert consultation, and (4) finalization. Results: The conceptual model has intention as its central construct to practice LTPA, and intention is directly influenced by dynamic interrelated processes between individual’s economic, psychosocial, and perceived physical environment factors. Conclusion: From the multiple theories, evidence, and expert agreement, we are confident that our conceptual model expresses the dynamic interactions which shape an individual’s decision to practice LTPA in a context of socioeconomic inequalities. Going forward, this work will be used to conceptualize and inform the development of an agent-based model to simulate LTPA inequalities among adults and can be expanded or adapted to other uses, such as intervention development