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Background: Previous studies have primarily focused on the links between fine particulate matter (PM2.5) and bone health among the general population instead of PM2.5 components and the specific population. We aimed to investigate the associations between PM2.5 components and bone health among middle-aged and elderly women. Methods: A total of 748 middle-aged and elderly women were randomly sampled from 32 streets/villages in Hubei Province. The concentrations of ambient PM2.5 and its components were extracted across various residential areas from the Tracking Air Pollution in China (TAP) dataset. Bone mineral density measurements were obtained from dual-energy X-ray absorptiometry scans of study participants. Multivariable logistic and linear models were employed to assess the relationship between PM2.5 and its components and bone loss. Results: Per interquartile range (IQR) increase in nitrate (NO3−) and ammonium (NH4+) concentrations were associated with 1.65 [95% confidence intervals (CI): 1.13, 2.30] and 1.77 (95% CI: 1.26, 2.49) times higher odds of osteoporosis, respectively. Long-term exposure to sulfate (SO42−), NO3−, and NH4+ was negatively associated with T-scores and bone mineral density in L1-L4 lumbar vertebrae. In addition, the elderly, women who have experienced menarche after the age of 14, and postmenopausal women were more susceptible to the water-soluble inorganic salts of PM2.5. Conclusion: The study emphasizes the need for comprehensive policies addressing air quality, with a specific focus on vulnerable populations such as middle-aged and elderly women. Public health interventions aimed at reducing ambient PM2.5 concentrations and minimizing exposure to its harmful components are crucial in mitigating the adverse impact on skeletal health and improving the overall well-being of communities. [ABSTRACT FROM AUTHOR]

In this paper, we consider variable-length coding over the memoryless binary asymmetric channel (BAC) with full noiseless feedback, including the binary symmetric channel (BSC) as a special case. In 2012, Naghshvar et al. introduced a coding scheme, which we refer to as the small-enough-difference (SED) coding scheme. For symmetric binary-input channels, the deterministic variable-length feedback (VLF) code constructed with the SED coding scheme asymptotically achieves both capacity and Burnashev’s optimal error exponent. Building on the work of Naghshvar et al., this paper extends the SED coding scheme to the BAC and develops a non-asymptotic VLF achievability bound that is shown to achieve both capacity and the optimal error exponent. For the specific case of the BSC, we develop an additional non-asymptotic VLF achievability bound using a two-phase analysis that leverages both a submartingale synthesis and a Markov chain time of first passage analysis. Numerical evaluations show that both new VLF achievability bounds outperform Polyanskiy’s achievability bound for variable-length stop-feedback codes. [ABSTRACT FROM AUTHOR]

Background: Sleep disturbance is common in patients with heart failure. The aims of this study were to assess the prevalence of sleep disturbance in patients with heart failure, and to examine the serial multiple mediation effects of psychological distress and sleep hygiene practices on the relationship between symptom burden and sleep quality. Methods: We recruited eligible heart failure patients in a large, university‐affiliated hospital in Shandong Province, China, from November 2018 to June 2019. The Pittsburgh Sleep Quality Index, Heart Failure Somatic Perception Scale, Hospital Anxiety and Depression Scale, and Sleep Hygiene Practice Scale were used to assess patients' sleep quality, symptom burden, psychological distress, and sleep hygiene practices. The mediation effects were analyzed using the PROCESS tool in SPSS. Results: Two hundred and thirty seven heart failure patients were included in the final analyses. Among these patients, 189 patients (67.1%) had a sleep disturbance (Pittsburgh Sleep Quality Index score of >5). Higher symptom burden, higher level of psychological distress, and poorer sleep hygiene practices were associated with patients' poorer sleep quality. The psychological distress and sleep hygiene practices had mediation effects on the relationship between symptom burden and sleep quality in patients with heart failure. Conclusions: Patients' symptom burden could affect their sleep quality through psychological distress and sleep hygiene practices besides a direct effect. Thus, psychological distress and sleep hygiene practices should be fully considered in the development of interventions to improve patients' sleep quality, apart from alleviating patients' symptom burden. [ABSTRACT FROM AUTHOR]

The rapid development and application of nuclear technology have been accompanied by the production of large amounts of radioactive wastes, of which Sr is a typical nuclide. In this study, six typical materials with strong adsorption properties, namely activated carbon, kaolin, montmorillonite, bentonite, zeolite, and attapulgite, were selected. Their adsorption mechanisms were investigated by analyzing their adsorption isotherms, adsorption kinetics, micromorphologies, element contents, specific surface areas, crystal structures, and functional groups. The results showed that the adsorption efficiency of Sr by the six adsorbents can be ranked as zeolite, bentonite, attapulgite, montmorillonite, activated carbon, and kaolin, among which the maximum adsorption capacity of zeolite was 4.07 mg/g. Based on the adsorption kinetic and thermodynamic fitting results, the adsorption of Sr by zeolites, bentonite and attapulgite is consistent with Langmuir model, the pseudo-first-order and pseudo-second-order model, and the adsorption process of Sr (II) by montmorillonite, activated carbon and kaolinite is consistent with the Freundlich model and corresponds to non-uniform adsorption. The main mechanisms of the six materials are physical adsorption, ion exchange and complexation. In summary, zeolite, bentonite, and attapulgite, especially zeolite, are highly effective for the treatment of radioactive wastewater containing strontium and have great application value in the treatment of radioactive wastes. [ABSTRACT FROM AUTHOR]

We consider the concatenation of a convolutional code (CC) with an optimized cyclic redundancy check (CRC) code as a promising paradigm for good short blocklength codes. The resulting CRC-aided convolutional code naturally permits the use of serial list Viterbi decoding (SLVD) to achieve maximum-likelihood decoding. The convolutional encoder of interest is of rate- $1/\omega $ and the convolutional code is either zero-terminated (ZT) or tail-biting (TB). The resulting CRC-aided convolutional code is called a CRC-ZTCC or a CRC-TBCC. To design a good CRC-aided convolutional code, we propose the distance-spectrum optimal (DSO) CRC polynomial. A DSO CRC search algorithm for the TBCC is provided. Our analysis reveals that the complexity of SLVD is governed by the expected list rank which converges to 1 at high SNR. This allows a good performance to be achieved with a small increase in complexity. In this paper, we focus on transmitting 64 information bits with a rate-1/2 convolutional encoder. For a target error probability $10^{-4}$ , simulations show that the best CRC-ZTCC approaches the random-coding union (RCU) bound within 0.4 dB. Several CRC-TBCCs outperform the RCU bound at moderate SNR values. [ABSTRACT FROM AUTHOR]

Freezing and thawing can cause dynamic fluctuations of the groundwater level, resulting in the migration and retention of LNAPLs. However, this process is difficult to observe visually, and a suitable simulation method for its quantitative calculation is lacking. In this study, a numerical simulation is established by coupling the HYDRUS-1D software and the TOUGH program to realize dynamic simulation of the entire process of soil temperature changes, water migration, water level fluctuation, and redistribution of LNAPLs during the freeze–thaw process. The results of the study show that the process of soil freezing and thawing causes water migration, which in turn causes groundwater level fluctuation, leading to the migration and redistribution of LNAPLs within the water level fluctuation zone. In this process, the soil particle size and porosity control the response degree and speed of the water level under freezing and thawing and the spatiotemporal distribution of LNAPLs by affecting the soil temperature, capillary force, and water migration. The migration ability of free LNAPLs is determined by their own density and viscosity; the retention of residual LNAPLs is affected by soil porosity and permeability as well as LNAPL viscosity. The results of this study can not only be used to develop a simulation method for the migration and retention mechanism of LNAPLs in cold regions but also serve as a scientific and theoretical basis for LNAPL pollution control in seasonal frozen soil regions. [ABSTRACT FROM AUTHOR]

Background: Although a mobile nursing application has began to adopt in nursing, few studies have focused on nurses' behavioral intention of it. The objective of this study is to gain insight into the behavioral intention of nurses, i.e. chinese nurses of the future, to use a mobile nursing application. This study adopted an extension of the Unified Theory of Acceptance and Use of Technology to examine Chinese nurses' acceptance of a mobile nursing application.Methods: A total of 1207 nurses participated in the cross-sectional survey. The majority of nurses were female (96.2%). The mean age of the participants was 34.18 (SD 7.39). The hypothesized relationships were tested using AMOS structural equation model.Results: All constructs exhibited an acceptable level of reliability and validity with Cα and CR > 0.7 and AVE > 0.5. An extension of the Unified Theory of Acceptance and Use of Technology Model had good explanatory power for nurses' behavioral intention of a mobile nursing application. Although effort expectancy and perceived risks had a surprisingly insignificant effect on nurses' behavioral intention to use a mobile nursing application, performance expectancy, social influence, facilitating conditions, self-efficacy, and perceived incentives demonstrated significant influence with β = .259, p < .001, β = .296, p < .001, β = .063, p = .037, β = .344, p < .001, β = .091, p = .001, respectively.Conclusion: With 70.2% of the variance in behavioral intention to use a mobile nursing app explained by this model, it could be helpful for potential adopters, and further investigation should test the actual usage behavior for a mobile nursing app and investigate the related factors. [ABSTRACT FROM AUTHOR]

The electronic and magnetic properties of magnetically doped transition-metal dichalcogenides are examined via first-principles calculations. With the confinement of wavefunctions in the two-dimensional space, substitutional doping of transition-metal elements can induce magnetism and spin splitting at band edges through the exchange interaction. Specifically, MX2 monolayers with M = (Mo, W) and X = (S, Se, Te) are explored for a range of dopants such as Fe, Mn, Co, Zn, Cd, V, Cu, and Sc. Among those studied, the results show that Fe and Mn may be promising candidates with large local magnetic moments. The exchange interaction in these two cases also appears to be Kondo-like. In addition, V and Sc are identified as the p-dopants for carrier-mediated magnetism despite their small magnetic moments. The effective exchange constants in Fe-doped and Mn-doped systems are deduced from the first-principles results and may be useful in the diluted systems, where the direct calculation is challenging. [ABSTRACT FROM AUTHOR]

This paper presents a new technique for real-time relighting of static scenes with all-frequency shadows from complex lighting and highly specular reflections from spatially varying BRDFs. The key idea is to depict the boundaries of visible regions using piecewise linear functions, and convert the shading computation into double product integrals—the integral of the product of lighting and BRDF on visible regions. By representing lighting and BRDF with spherical Gaussians and approximating their product using Legendre polynomials locally in visible regions, we show that such double product integrals can be evaluated in an analytic form. Given the precomputed visibility, our technique computes the visibility boundaries on the fly at each shading point, and performs the analytic integral to evaluate the shading color. The result is a real-time all-frequency relighting technique for static scenes with dynamic, spatially varying BRDFs, which can generate more accurate shadows than the state-of-the-art real-time PRT methods. [ABSTRACT FROM PUBLISHER]

Shadow maps sample scene visibility in the light source space and offer an efficient solution to generate hard shadows. However, they suffer from aliasing artifacts because of discretization errors, inadequate resolution and projection distortion. In this paper, we propose the shadow geometry map method, where a shadow depth map is augmented by storing geometry information about scenes. This leads to a new shadowrendering algorithm that combines a supersampling filter, a geometry-aware reconstruction kernel and an irregular sampling filter. Our method produces high quality alias-free and subpixel supersampling shadow rendering and retains the simplicity and the efficiency of shadow maps. We show that the algorithm pipeline is efficiently parallelized using current programmable graphics hardware and that our method is capable of generating high quality hard shadows. [ABSTRACT FROM AUTHOR]