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A dual-band dual-polarized wearable antenna that applies to two different operating modes of wireless body area networks is proposed in this letter. The antenna radiates simultaneously in the ISM band at 2.45 and 5.8 GHz. It consists of a rigid button-like radiator and a flexible fabric radiator. At 2.45 GHz, an omnidirectional circularly polarized pattern is radiated by the flexible radiator, which is suitable for the on-body communication. At the same time, a linearly polarized broadside pattern for off-body communication is generated by button radiator at 5.8 GHz. The antenna has been validated in free space and human body environments. The impedance bandwidth at 2.45 and 5.8 GHz are 5% and 35%, and the gain is measured to be 0.15 and 5.95 dBi, respectively. Furthermore, the specific absorption rates are simulated. At 2.45 and 5.8 GHz, the results averaged over 1 g of body tissue are 0.128 and 0.055 W/kg. The maximum value at both bands is below the IEEE C95.3 standard of 1.6 W/kg.
Femoral neck bone mineral density (FNBMD) is a high risk factor for femoral head fractures, and coffee intake affects bone mineral density, but the effect on FNBMD remains to be explored. First, we conducted an observational study in the National Health and Nutrition Examination Survey and collected data on coffee intake, FNBMD, and sixteen covariates. Weight linear regression was used to explore the association of coffee intake with FNBMD. Then, Mendelian randomisation (MR) was used to explore the causal relationship between coffee intake and FNBMD, the exposure factor was coffee intake, and the outcome factor was FNBMD. The inverse variance weighting (IVW) method was used for the analysis, while heterogeneity tests, sensitivity, and pleiotropy analysis were performed. A total of 5 915 people were included in the cross-sectional study, including 3 178 men and 2 737 women. In the completely adjusted model, no coffee was used as a reference. The ORs for the overall population at ‘< 1’, ‘1–<2’, ‘2–<4’, and ‘4+’ (95% CI) were 0.02 (–0.01, 0.04), 0.00 (–0.01, 0.02), –0.01 (–0.02, 0.00), and 0.00 (–0.01, 0.02), respectively. The male and female population showed no statistically significant differences in both univariate and multivariate linear regressions. In the MR study, the IVW results showed an OR (95% CI) of 1.06 (0.88–1.27), a P-value of 0.55, and an overall F-value of 80.31. The heterogeneity, sensitivity analyses, and pleiotropy had no statistical significance. Our study used cross-sectional studies and MR to demonstrate that there is no correlation or causal relationship between coffee intake and FNBMD.
Background: Traumatic brain injury (TBI) patients exhibit variable post-injury recovery trajectories. Days at Home (DAH) is a patient-centered measure that captures healthcare transitions and offers a more nuanced understanding of recovery. Here, we use DAH to characterize longterm recovery trajectories for moderate to severe TBI (msTBI) survivors. Methods: This multicenter retrospective cohort study utilized population health data from Ontario to identify adults sustaining isolated msTBI hospitalized between 2009-2021. DAH were calculated in distinct 30-day intervals from index admission to 3 years post-injury; latent class mixed modeling identified unique recovery trajectories and trajectory attributes were quantified. Results: There were 2,510 patients eligible for latent class analysis. Four DAH trajectories were identified: early recovery (69.9%), intermediate recovery (11.4%), late recovery (2.9%), and poor recovery (15.8%). Patients in the poor recovery group were older, more frail, and had lower admission GCS scores, while those in early recovery exhibited lower acute care needs. Intermediate and late recovery groups exhibited protracted transitions home, with near-complete reintegration by 24 months. A prediction model distinguished unfavorable trajectories with good accuracy (C-index=0.824). Conclusions: Despite high initial institutional care requirements, 85% of patients reintegrated into the community within three years of msTBI. These findings shed light on post-injury care requirements for brain-injured patients.
Background: Artificial intelligence (AI) holds promise to predict outcomes for patients sustaining moderate to severe traumatic brain injury (msTBI). This systematic review sought to identify studies utilizing AI-based methods to predict mortality and functional outcomes after msTBI, where prognostic uncertainty is highest. Methods: The APPRAISE-AI quantitative evidence appraisal tool was used to evaluate methodological quality of included studies by determining overall scores and domain-specific scores. We constructed a multivariable linear regression model using study sample size, country of data collection, publication year and journal impact factor to quantify associations with overall APPRAISE-AI scores. Results: We identified 38 studies comprising 591,234 patients with msTBI. Median APPRAISE-AI score was 45.5 (/100 points), corresponding to moderate study quality. There were 13 low-quality studies (34%) and only 5 high-quality studies (13%). Weakest domains were methodological conduct, robustness of results and reproducibility. Multivariable linear regression highlighted that higher journal impact factor, larger sample size, more recent publication year and use of data that were collected in a high-income country were associated with higher APPRAISE-AI overall scores. Conclusions: We identified several study weaknesses of existing AI-based prediction models for msTBI; this work highlights methodological domains that require quality improvement to ultimately ensure safety and effiicacy of clinical AI models.
This study was designed to explore changes in soil bulk density (BD), soil organic carbon (SOC) content, SOC stocks, and soil labile organic carbon (C) fractions after 5 years of soil tillage management under the double-cropping rice system in southern of China. The experiment included four soil tillage treatments: rotary tillage with all crop residues removed as a control (RTO); conventional tillage with crop residues incorporation (CT); rotary tillage with crop residues incorporation (RT); and no-tillage with crop residues retention. Our results revealed that soil tillage combined with crop residue incorporation (CT and RT) significantly decreased BD at 0–20 cm soil layer compared to RTO treatment. SOC content and stocks were increased with the application of crop residues. Compared with RTO treatment, SOC content and stocks were increased by 16.8% and 9.8% in CT treatment, respectively. Soil non-labile C content and proportion of labile C were increased due to crop residue incorporation. Compared with RTO treatment, soil proportion of C mineralisation (Cmin), permanganate oxidisable C (KMnO4), particulate organic C (POC), and microbial biomass C (MBC) was increased by 196.1%, 41.4%, 31.4%, and 17.1% under CT treatment, respectively. These results were confirmed by the carbon management index, which was significantly increased under soil tillage with crop residue incorporation. Here, we demonstrated that soil tillage and crop residue incorporation can increase the pool of stable C at surface soil layer while increasing labile C content and proportion. In conclusion, conventional or rotary tillage combined with crop residue incorporation is a soil management able to improve nutrient cycling and soil quality in paddy fields in southern China.
The flow of an incompressible fluid in a rapidly rotating cubic cavity librating at a low frequency around an axis through the midpoints of opposite edges features synchronous waves with a foliation pattern that is quasi-invariant in the axial direction. These waves are emitted from the equatorial edges (the edges furthest away from the axis) and travel into the interior in a retrograde fashion about the eastern equatorial vertices. These waves are interpreted as topographic Rossby waves, consistent with the lack of closed geostrophic contours for the rotating container. They are analysed in detail at small Ekman numbers, both in the linear regime, corresponding to the limit of zero libration amplitude (Rossby number $ Ro \to 0$), and in the weakly nonlinear regime with small but finite $ Ro$. The waves subsist in the linear regime and coexist with a network of shear layers that are predicted by linear inviscid analysis to focus towards the equatorial edges. However, viscous effects stop the focusing at a distance from the edges that scales with $E^{1/2}$. The large inclination of the oblique walls with the rotation axis, together with the vanishing depth at the equatorial edges, provide the conditions for singular behaviour in the Rossby waves as $E\to 0$. Within a distance of the eastern equatorial vertices also scaling with $E^{1/2}$, the nonlinear contributions have a self-similar structure whose enstrophy density scales as $E^{-16/3} Ro ^2$. This means that $ Ro$ must be reduced considerably faster than $E$ for nonlinear contributions to be negligible as $E\to 0$.
Hand, foot, and mouth disease (HFMD) shows spatiotemporal heterogeneity in China. A spatiotemporal filtering model was constructed and applied to HFMD data to explore the underlying spatiotemporal structure of the disease and determine the impact of different spatiotemporal weight matrices on the results. HFMD cases and covariate data in East China were collected between 2009 and 2015. The different spatiotemporal weight matrices formed by Rook, K-nearest neighbour (KNN; K = 1), distance, and second-order spatial weight matrices (SO-SWM) with first-order temporal weight matrices in contemporaneous and lagged forms were decomposed, and spatiotemporal filtering model was constructed by selecting eigenvectors according to MC and the AIC. We used MI, standard deviation of the regression coefficients, and five indices (AIC, BIC, DIC, R2, and MSE) to compare the spatiotemporal filtering model with a Bayesian spatiotemporal model. The eigenvectors effectively removed spatial correlation in the model residuals (Moran’s I < 0.2, p > 0.05). The Bayesian spatiotemporal model’s Rook weight matrix outperformed others. The spatiotemporal filtering model with SO-SWM was superior, as shown by lower AIC (92,029.60), BIC (92,681.20), and MSE (418,022.7) values, and higher R2 (0.56) value. All spatiotemporal contemporaneous structures outperformed the lagged structures. Additionally, eigenvector maps from the Rook and SO-SWM closely resembled incidence patterns of HFMD.
Objectives/Goals: Obesity has been classified as a global epidemic and origin of numerous health issues. The central hypothesis of this study is that psychological measures, DNA methylation, and gene transcription will predict obesity-related outcomes after lifestyle interventions, and such interventions may alter DNA methylation profiles. Methods/Study Population: This study consisted of a randomized-controlled trial examining the effects of lifestyle +/- stress reduction interventions in 285 highly stressed parents with obesity, followed for 2 years. Full participants received nutrition and activity counseling, and were randomized to either a stress reduction intervention or a contact control. Those who otherwise qualified for the study but unable to fully participate were included in a no intervention control group. The intervention consisted of 12 weeks of nutrition and activity counseling +/- 2-hour weekly stress reduction interventions using MBSR and CBT-based strategies. DNA methylation was assessed using Illumina EPIC arrays. Results/Anticipated Results: Using linear mixed models (LMMs), this study will first examine the hypothesis that baseline psychological measures and pre-existing methylation sites associated with obesity and glycemic control (e.g., ABCG1, ATP10A, TXNIP, SREBF1, RNF39, and SOCS3) predict changes in BMI, HOMA-IR, and HgbA1C post-intervention and at 1 and 2 year follow-ups. Using sites that demonstrate statistical significance, we will develop a polymethylation risk score predictor of change in BMI. Next, we will examine the hypothesis that interventions which reduce obesity may also lead to improvements in epigenetic aging using LMMs to determine if changes in BMI or HOMA-IR predict changes in epigenetic age acceleration over the course of the study. Discussion/Significance of Impact: This work examines whether psychological factors and/or epigenetic markers may be used in patient stratification at initiation of treatment, enabling improved treatment selection, fewer years of obesity and decreased risk of comorbidities. This proposal also asks whether lifestyle interventions impact the aging process itself.
We presented an attosecond-precision timing detector based on linear optics. The minimum measurement floor is 1×10–10 fs2/Hz with only 1 mW input optical power. With this novel technique, the residual dispersion of a 5.2 km fiber link is characterized and precisely compensated. Finally, a comprehensive feedback model has been developed to analyze the noise coupling in a long-distance link stabilization system. The simulation results demonstrate an out-of-loop jitter of merely 359 as, integrated at [1 Hz, 1 MHz], at 1 mW input power per photodetector of our timing detector. Remarkably, the system is capable of maintaining sub-femtosecond precision even at optical power levels as low as 240 nW (for a 5.2 km link length), or link lengths as long as 20 km (with 1 μW optical power), respectively.
This study investigates how institutional origin affects the dot tax haven (DTH) internationalization of Chinese family firms (FFs). Drawing on institutional theory and the mixed gamble perspective, we propose that restructured FFs (RFFs), originating from state-owned enterprises (SOEs), are more likely to engage in DTH internationalization than entrepreneurial FFs directly established by family founders. This propensity is attributed to the institutional legacies inherited from their SOE predecessors, which create a distinct potential gain-loss calculus. Our empirical analysis of publicly listed Chinese FFs from 2012 to 2021 demonstrates that restructured FFs are 30% more likely to use DTH and establish 43% more DTH subsidiaries than entrepreneurial FFs. This tendency, however, is mitigated by the firms’ economic ties to financial institutions. Our study enhances understanding of FFs’ global entrepreneurial decision-making, contributing to FF heterogeneity research. A novel aspect of our study is examining the impact of institutional legacies on FFs – a topic less explored in family business literature. Furthermore, our findings provide insights for policymakers and regulators, emphasizing the importance of tailored policies that consider the intricate interplay between institutional origin and contemporary entrepreneurial goals in FFs.
This study investigates the extent to which a group of Australian preservice and early career secondary school music teachers of East Asian heritage are likely to teach aspects of their heritage music. It is positioned against a background of national multiculturalism and approaches to cultural inclusivity in Australian society, as well as the long-standing notion of ‘Asia literacy’ in Australian education and the national cross-curriculum priority (C-CP) of ‘Asia and Australia’s engagement with Asia’. The study’s findings indicate that the participants identified with their ancestral cultures to varying extents, generally had very limited knowledge of and experience with their heritage music and in general were reluctant to teach their heritage music. The authors suggest that the slow rate of progress towards culturally diversifying Australian music classrooms is related to complex matters and attitudes surrounding race in the country. The study proposes developing Cayari’s concept of ‘Asian spaces’ as a means of increasing the presence of East Asian music in Australian schools and of supporting teachers of East Asian heritage in the workplace. Finally, the authors emphasise that culturally diversifying the content of music classrooms can be undertaken by teachers of any cultural background.
Machine learning (ML) models have been developed to identify randomised controlled trials (RCTs) to accelerate systematic reviews (SRs). However, their use has been limited due to concerns about their performance and practical benefits. We developed a high-recall ensemble learning model using Cochrane RCT data to enhance the identification of RCTs for rapid title and abstract screening in SRs and evaluated the model externally with our annotated RCT datasets. Additionally, we assessed the practical impact in terms of labour time savings and recall improvement under two scenarios: ML-assisted double screening (where ML and one reviewer screened all citations in parallel) and ML-assisted stepwise screening (where ML flagged all potential RCTs, and at least two reviewers subsequently filtered the flagged citations). Our model achieved twice the precision compared to the existing SVM model while maintaining a recall of 0.99 in both internal and external tests. In a practical evaluation with ML-assisted double screening, our model led to significant labour time savings (average 45.4%) and improved recall (average 0.998 compared to 0.919 for a single reviewer). In ML-assisted stepwise screening, the model performed similarly to standard manual screening but with average labour time savings of 74.4%. In conclusion, compared with existing methods, the proposed model can reduce workload while maintaining comparable recall when identifying RCTs during the title and abstract screening stages, thereby accelerating SRs. We propose practical recommendations to effectively apply ML-assisted manual screening when conducting SRs, depending on reviewer availability (ML-assisted double screening) or time constraints (ML-assisted stepwise screening).
In the digital era, short videos have become a significant form of digital copyright, yet the debate over whether stronger copyright protection enhances their creation continues. To contribute to this discourse, we conducted an analysis based on a representative sample of short videos on a prominent Chinese short video platform, Douyin. Capitalizing on an external regulatory intervention, specifically the Campaign against Online Infringement and Piracy (COIP) implemented by the Chinese government, we employed the difference-in-differences (DID) method to assess the impact of reinforced copyright protection on the originality of short videos. Our findings reveal that strengthened copyright protection leads to a significant increase in the originality of short videos. Further research on creator heterogeneity shows that influencers exhibit a significantly more positive response to strengthened copyright protection than amateur creators. Finally, we present evidence explaining how external regulation works by enhancing intra-platform regulation. These results have rich implications for intellectual property protection, digital innovation management, and platform regulation.
We aim to test the hypothesis that overconfidence arises as a strategy to influence others in social interactions. To address this question, we design an experiment in which participants are incentivized either to form accurate beliefs about their performance at a test, or to convince a group of other participants that they performed well. We also vary participants’ ability to gather information about their performance. Our results show that participants are more likely to (1) overestimate their performance when they anticipate that they will try to persuade others and (2) bias their information search in a manner conducive to receiving more positive feedback, when given the chance to do so. In addition, we also find suggestive evidence that this increase in confidence has a positive effect on participants’ persuasiveness.
This study aimed to assess the concordance between different anthropometric indexes in the Global Leaders Initiated Malnutrition Standards (GLIM) and the Geriatric Risk Index (GNRI) for evaluating muscle mass, while also exploring performance-based criteria for GLIM muscle content suitable for elderly patients with intermediate and advanced tumors. A total of 312 patients admitted to Shanghai Tenth People’s Hospital between September 2022 and June 2023 were retrospectively included. Nutritional assessments were conducted using the GLIM framework, employing grip strength, upper arm circumference, and calf circumference as criteria for muscle content evaluation. The diagnostic value of these tools was compared against the GNRI as a reference standard. Among the participants, 127 (40.71%) were diagnosed as malnourished by GNRI, while the GLIM assessments yielded 138 (44.23%), 128 (41.03%), and 162 (51.92%) malnutrition diagnoses based on grip strength, calf circumference, and upper arm circumference, respectively. Both GNRI and GLIM-grip strength were significantly associated with complications and length of hospital stays. Notably, using GNRI as a reference, GLIM-grip strength demonstrated good consistency in diagnosing malnutrition (K value = 0.692, P < 0.001), with calf circumference having the highest diagnostic value. In conclusion, grip strength is a practical and effective performance-based criterion within the GLIM standards and has the potential to enhance malnutrition diagnosis in elderly patients with advanced malignancies, highlighting its relevance in nutritional science.
The betatron radiation source features a micrometer-scale source size, a femtosecond-scale pulse duration, milliradian-level divergence angles and a broad spectrum exceeding tens of keV. It is conducive to the high-contrast imaging of minute structures and for investigating interdisciplinary ultrafast processes. In this study, we present a betatron X-ray source derived from a high-charge, high-energy electron beam through a laser wakefield accelerator driven by the 1 PW/0.1 Hz laser system at the Shanghai Superintense Ultrafast Laser Facility (SULF). The critical energy of the betatron X-ray source is 22 ± 5 keV. The maximum X-ray flux reaches up to 4 × 109 photons for each shot in the spectral range of 5–30 keV. Correspondingly, the experiment demonstrates a peak brightness of 1.0 × 1023 photons·s−1·mm−2·mrad−2·0.1%BW−1, comparable to those demonstrated by third-generation synchrotron light sources. In addition, the imaging capability of the betatron X-ray source is validated. This study lays the foundation for future imaging applications.
Robust schemes in regression are adapted to mean and covariance structure analysis, providing an iteratively reweighted least squares approach to robust structural equation modeling. Each case is properly weighted according to its distance, based on first and second order moments, from the structural model. A simple weighting function is adopted because of its flexibility with changing dimensions. The weight matrix is obtained from an adaptive way of using residuals. Test statistic and standard error estimators are given, based on iteratively reweighted least squares. The method reduces to a standard distribution-free methodology if all cases are equally weighted. Examples demonstrate the value of the robust procedure.
Current practice in factor analysis typically involves analysis of correlation rather than covariance matrices. We study whether the standard z-statistic that evaluates whether a factor loading is statistically necessary is correctly applied in such situations and more generally when the variables being analyzed are arbitrarily rescaled. Effects of rescaling on estimated standard errors of factor loading estimates, and the consequent effect on z-statistics, are studied in three variants of the classical exploratory factor model under canonical, raw varimax, and normal varimax solutions. For models with analytical solutions we find that some of the standard errors as well as their estimates are scale equivariant, while others are invariant. For a model in which an analytical solution does not exist, we use an example to illustrate that neither the factor loading estimates nor the standard error estimates possess scale equivariance or invariance, implying that different conclusions could be obtained with different scalings. Together with the prior findings on parameter estimates, these results provide new guidance for a key statistical aspect of factor analysis.