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Virtual Integration of Satellite and In-situ Observation Networks (VISION) v1.0: In-Situ Observations Simulator (ISO_simulator)
No full textThis work presents the first step in the development of the VISION toolkit, a set of Python tools that allows easy, efficient, and more meaningful comparison between global atmospheric models and observational data. Whilst observational data and modelling capabilities are expanding in parallel, there are still barriers preventing these two data sources from being used in synergy. This arises from differences in spatial and temporal sampling between models and observational platforms: observational data from a research aircraft, for example, are sampled on specified flight trajectories at very high temporal resolution. Proper comparison with model data requires generating, storing, and handling a large number of highly temporally resolved model files, resulting in a process which is data-, labour-, and time-intensive. In this paper we focus on comparison between model data and in situ observations (from aircraft, ships, buoys, sondes, etc.). A standalone code, In-Situ Observations Simulator, or ISO_simulator for short, is described here: this software reads modelled variables and observational data files and outputs model data interpolated in space and time to match observations. These model data are then written to NetCDF files that can be efficiently archived due to their small sizes and directly compared to observations. This method achieves a large reduction in the size of model data being produced for comparison with flight and other in situ data. By interpolating global gridded hourly files onto observation locations, we reduce data output for a typical climate resolution run, from ∼3 Gb per model variable per month to ∼15 Mb per model variable per month (a 200-times reduction in data volume). The VISION toolkit is relatively fast to run and can be automated to process large volumes of data at once, allowing efficient data analysis over a large number of years. Although this code was initially tested within the Unified Model (UM) framework, which is shared by the UK Earth System Model (UKESM), it was written as a flexible tool and it can be extended to work with other models
Measurable Residual Disease-Guided Therapy for Chronic Lymphocytic Leukemia
No full textBackground
An interim analysis of progression-free survival in this trial showed that ibrutinib–venetoclax was superior to fludarabine–cyclophosphamide–rituximab (FCR) among patients with chronic lymphocytic leukemia (CLL). Whether ibrutinib–venetoclax is more effective than ibrutinib alone is unclear.
Methods
In this phase 3, multicenter, open-label trial, we randomly assigned patients with CLL to receive ibrutinib–venetoclax, ibrutinib alone, or FCR. The primary end points were undetectable measurable residual disease (MRD) in bone marrow within 2 years in the ibrutinib–venetoclax group as compared with the ibrutinib-alone group and progression-free survival in the ibrutinib–venetoclax group as compared with the FCR group. A powered secondary end point was progression-free survival in the ibrutinib–venetoclax group as compared with the ibrutinib-alone group. Other secondary end points included overall survival.
Results
A total of 172 of the 260 participants (66.2%) in the ibrutinib–venetoclax group had undetectable MRD in bone marrow within 2 years, as compared with none of the 263 participants in the ibrutinib-alone group (P<0.001) and 127 of the 263 participants (48.3%) in the FCR group. With a median follow-up of 62.2 months, disease progression or death occurred in 18 participants (6.9%) in the ibrutinib–venetoclax group, as compared with 59 (22.4%) in the ibrutinib-alone group (hazard ratio, 0.29; 95% confidence interval [CI], 0.17 to 0.49; P<0.001) and 112 (42.6%) in the FCR group (hazard ratio, 0.13; 95% CI, 0.08 to 0.21; P<0.001). Progression-free survival at 5 years was 93.9% with ibrutinib–venetoclax, 79.0% with ibrutinib alone, and 58.1% with FCR. Death occurred in 11 participants (4.2%) in the ibrutinib–venetoclax group, as compared with 26 (9.9%) in the ibrutinib-alone group (hazard ratio, 0.41; 95% CI, 0.20 to 0.83) and 39 (14.8%) in the FCR group (hazard ratio, 0.26; 95% CI, 0.13 to 0.50). Sudden death occurred in 3, 8, and 4 participants in the ibrutinib–venetoclax, ibrutinib-alone, and FCR groups, respectively.
Conclusions
With extended follow-up and increased enrollment, our trial showed that undetectable MRD and extended progression-free survival were more common with ibrutinib–venetoclax than with ibrutinib alone or FCR. The results for overall survival were also consistent with a benefit of ibrutinib–venetoclax. (Funded by Cancer Research UK and others; FLAIR ISRCTN Registry number, ISRCTN01844152; EudraCT number, 2013-001944-76.
Effects of atomic structures at Co2Fe(Al0.5,Si0.5)/Ge interfaces on spin-electronic properties
No full textEfficient spin injection is essential for the development of ferromagnet—semiconductor spintronic devices with high performances, including spin transistors. Although the Co2Fe(Al0.5,Si0.5) (CFAS)/Ge hybrid structure has been identified as an outstanding platform for such devices, there is a lack of systematic analyses on the effects of the interface atomic structure on the spin-electronic properties. In this study, we investigate electronic and magnetic properties of CFAS/Ge (001) interfaces by density functional theory calculations under two possible scenarios, with atomically abrupt bulk-like interfaces and with intermixing at the interfaces. For two possible terminations in the case of abrupt interfaces, we show considerable reductions in spin polarization (SP), which is emphasized in the case of the —Fe—Si,Al/Ge interface, where the SP has reversed sign. Further, we show that Fe—Ge interdiffusion is most likely to occur at the interface, and that this intermixing does not largely affect the spin-electronic properties. In contrast, the model of interdiffusion affecting the Co sublattice in the CFAS film exhibits a reversed SP at the interface layers, but this is less likely to occur owing to the higher energy for such atomic swaps. Band alignment analyses show that interfaces with a small degree of Fe/Ge intermixing could be beneficial for the spin injection efficiency. This study demonstrates that the spin injection efficiency is strongly dependent on the ferromagnet—semiconductor interface atomic structure, and thus can guide further theoretical and experimental studies for development of spintronic devices with improved properties
Is our growing affinity for technology a challenge for preventing distracted cycling? An Australian study
No full textObjectives
The core aim of this study was to assess secondary task engagement among Australian cyclists, considering demographic, behavioral, and psychosocial factors as potential contributors.
Methods
This study used the information provided by a sample of 1,240 Australian cyclists (24% females; 74% males; 2% non-binary) aged M = 53.6 (SD 12.9) years. They responded to an online survey on cycling-related affairs, including demographic, psychosocial (Risk Perception and Regulation Scale, RPRS), behavioral (Cycling Behavior Questionnaire, CBQ), and technology-related (Affinity for Technology Questionnaire, TAEG) factors.
Results
After analyzing the TAEG properties and outcomes in this Australian sample, it was found that engagement in secondary tasks while riding varies significantly according to demographic and cycling behavioral profiles. For instance, older cyclists were less likely to report engaging in secondary tasks while riding. In terms of cycling behavior, respondents who reported higher rates of violations were more likely to report high engagement with technology while riding. Moreover, the results from a multilinear regression model predicting secondary task engagement indicated associations between self-reported cycling behavior and engagement in secondary tasks, as well as a strong relationship between traffic violations and the latter. Additionally, knowledge of traffic rules and self-reported positive behaviors showed a significant negative relationship with secondary task engagement, suggesting that these respondents were less inclined to use mobile devices while riding.
Conclusion
Overall, the findings of this study support the hypothesis that secondary task engagement can be statistically explained by demographic factors (such as age and gender), attitudinal factors, and cycling behavior. These findings highlight several challenges and implications for cycling safety practices, particularly considering the increasing normalization of technology-related secondary tasks in transport activities such as cycling
Toward Cultural Validation of the Revised Children's Anxiety and Depression Scale in Karnataka, India: Psychometric Testing Among 13–17‐Year Olds
No full textImproving youth mental health is a national priority in India, especially given the very high rates of youth suicide. Yet, mental health prevalence data in India are often incomplete. More culturally validated mental health measures are needed to inform prevention and intervention work. The Revised Children's Anxiety and Depression Scale (RCADS-47) is a widely used measure of mental health globally, including in India, but it is yet to be culturally validated there. This study presents the second stage (of two) of the cultural validation of the RCADS-47 in a sample of Indian adolescents (n = 332; Mage = 14.81 years). Participants completed a revised version of the RCADS-47 (K-RCADS), alongside comparative measures. Psychometric testing for convergent and discriminant validity, alongside factor analysis, was conducted. The K-RCADS had good psychometric properties; high internal reliability (α = 0.89) and good construct validity when compared to measures of similar constructs (r = 0.51–0.69). Support was found for five of the six original RCADS factors. Findings suggest confidence in the rephrased RCADS-47 ability to identify symptoms of anxiety and depression among Indian adolescents, alongside highlighting the importance of culturally validating measures of mental health. Further research in this validation is also discussed
Nonlinear propagating slow waves in cooling coronal magnetic loops
No full textWe study the propagation of slow magnetosonic waves in coronal magnetic loops. In our study we take nonlinearity and loop cooling into account. We use the small beta approximation and neglect the effect of magnetic field perturbation on the wave propagation. In accordance with this we assume that the tube cross-section does not change. We also neglect the equilibrium plasma density variation along and across the tube. As a result the equations of magnetohydrodynamics reduce to purely one-dimensional gasdynamic equations that includes the effect of viscosity and thermal conduction. We assume that the perturbation amplitude is sufficiently small and use the reductive perturbation method to derive the generalised Burgers’ equation describing the evolution of initial perturbations. First we study a case with weak dissipation and drop the term describing it. When there is no cooling the evolution of the initial perturbation results in a gradient catastrophe. However strong cooling can prevent it. Then we solve the full equation numerically assuming that the temperature decreases exponentially. We fix the initial perturbation amplitude and then study the dependence of perturbation evolution on the cooling time. The main result that we obtain is that moderate cooling decelerates the wave damping. This effect is related to the fact that the dissipation coefficients are proportional to the temperature in 5/2 power. As a result they decrease fast because of plasma cooling. However strong cooling can cause perturbation damping on its own
Critical role of non‐Fullerene crystalline domains in stabilizing charge separation in bulk heterojunction organic solar cells
No full textThis study addresses the role of energetic offsets resulting from non-fullerene acceptor crystallization/aggregation in stabilizing charge separation in organic bulk heterojunction (BHJ) solar cells. Devices are fabricated using PM6 as electron donor and either IDIC or Y6 as acceptor, with blend ratios from 5:1 to 1:1. Reducing acceptor content significantly lowers device performance, most notably for initially higher performing PM6:Y6 BHJ's (from 14.31% to 0.95%) compared to PM6:IDIC (from 11.28% to 3.40%). Optical, optoelectronic, and morphological characterizations reveal that lower acceptor content PM6:Y6 devices exhibit suppressed acceptor aggregation/crystallinity, correlated with increased recombination losses and lower efficiency. Charge separation in optimal (1:1) PM6:Y6 devices is found to be stabilized by a LUMO level energetic offset between intermixed and pure, more crystalline, Y6 domains, driven by strong electronic interactions between Y6 molecules. In contrast, PM6:IDIC devices show minimal changes in energetics and recombination kinetics, aligning with their smaller performance decline, and consistent with IDIC's weaker electronic interactions. As such strong electronic interactions between Y6 molecules are concluded to provide an energetic stabilization of electrons in more aggregated/crystalline Y6 domains, suppressing charge recombination, and analogous to that observed for the highest performing fullerene acceptor PCBM
Self-healing carboxymethyl chitosan hydrogel with anthocyanin for monitoring the spoilage of flesh foods
No full textSelf-healing hydrogels prepared with biopolymers have been widely applied in various engineering fields. In this study, the carboxymethyl chitosan (CMC) hydrogels were fabricated through crosslinking with oxidized alginate (ADA), which can be applied in smart food packaging fields. The concentration of oxidized alginate has greatest impact on the physicochemical properties of the hydrogels. Due to the dynamic properties of Schiff base linkages and hydrogen bonds, the hydrogel demonstrated self-healing. Higher concentrations of oxidized alginate result in weaker self-healing ability of the hydrogels. The self-healing properties endowed the hydrogel with 3D printable capacity. The anthocyanin (An) in the hydrogel exhibited a color change when exposed to acidic and basic gases, making the hydrogel potentially useful for smart indicators. These intelligent indicators can be used to detect the freshness of chicken, pork and fish. In addition, the hydrogel showed excellent biodegradable properties and can be degraded in lake, soil and simulated seawater. The self-healing, biodegradable and pH sensitive hydrogels has the potential to be applied in smart food packaging