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Adolescent mental health problems impose a significant burden. Exploring evolving social environments could enhance comprehension of their impact on mental health. We aimed to depict the trajectories of the neighborhood social exposome from middle to late adolescence and assess the intricate relationship between them and late adolescent mental health. Participants (n = 3965) from the FinnTwin12 cohort with completed questionnaires at age 17 were used. Nine mental health measures were assessed. The social exposome comprised 28 neighborhood social indicators. Trajectories of these indicators from ages 12 to 17 were summarized via latent growth curve modeling into growth factors, including baseline intercept. Mixture effects of all growth factors were assessed through quantile-based g-computation. Repeated generalized linear regressions identified significant growth factors. Sex stratification was performed. The linear-quadratic model was the most optimal trajectory model. No mixture effect was detected. Regression models showed some growth factors saliently linked to the p-factor, internalizing problems, anxiety, hyperactivity, and aggression. The majority of them were baseline intercepts. Quadratic growth factors about mother tongues correlated with anxiety among sex-combined participants and males. The linear growth factor in the proportion of households of couples without children was associated with internalizing problems in females. We were limited to including only neighborhood-level social exposures, and the multilevel contextual exposome situation interfered with our assessment. Trajectories of the social neighborhood exposome modestly influenced late adolescent mental health. Tackling root causes of social inequalities through targeted programs for living conditions could improve adolescent mental health. • Trajectories of the neighborhood social exposome were depicted in adolescence. • No mixture effect of trajectories on adolescent mental health was found. • Most of the growth factors selected by regression models were baseline intercepts. • Changes in neighborhood language and household structures linked with mental health. • Results may be affected by the multilevel contextual exposome situation. [ABSTRACT FROM AUTHOR]

The emergence and transmission of the colistin-resistance gene mcr and extended-spectrum β-lactamase (ESBL) encoding genes pose a significant threat to global public health. In recent years, it has been reported that mcr-1 and ESBL genes can coexist in single bacteria strain. The objective of this study was to characterize a multidrug-resistant (MDR) avian pathogenic Escherichia coli (APEC) isolate carrying mcr and ESBL encoding genes in China. A total of 200 APEC isolates were collected for antimicrobial susceptibility testing by Kirby–Bauer (K–B) disk method. The MDR strain EC012 were then further analyzed for minimum inhibitory concentrations, antimicrobials resistance genes (ARGs) detection, conjugation, and whole-genome sequencing (WGS). Among all APEC isolates determined by K–B disk method, strain EC012 was resistant to almost all the antimicrobials, including polymyxin B, cefotaxime, and ceftazidime. Moreover, EC012 harbored ARGs mcr-1, blaTEM-176, and blaCTX-M-14. WGS analysis revealed that EC012 belonged to epidemic APEC serotype O1:H16 and multilocus sequence type ST295. EC012 consisted of one chromosome and six plasmids, encoding a broad ARGs. The blaCTX-M-14, mcr-1 or blaTEM-176 genes were located on conjugative plasmids pEC012-1 or pEC012-5, respectively. These plasmids were successfully transferred to transconjugants and resulted in the resistance to polymyxin B, cefotaxime, and ceftazidime. This study indicated that APEC was a potential reservoir of colistin-resistance gene mcr-1 and ESBL encoding genes, and highlighted the necessity for enhanced monitoring of ARGs dissemination among bacteria from different origins. [ABSTRACT FROM AUTHOR]

With the rapid growth in the proportion of renewable energy access and the structural complexity of distributed energy systems, traditional microgrid (MG) scheduling methods that rely on mathematical optimization models and expert experience are facing significant challenges. Therefore, it is essential to present a novel scheduling technique with high intelligence and fast decision-making capacity to realize MGs' automatic operation and regulation. This paper proposes an optimal scheduling decision-making method for MGs based on deep neural networks (DNN). Firstly, a typical mathematical scheduling model used for MG operation is introduced, and the limitations of current methods are analyzed. Then, a two-stage optimal scheduling framework comprising day-ahead and intra-day stages is presented. The day-ahead part is solved by mixed integer linear programming (MILP), and the intra-day part uses a convolutional neural network (CNN)—bidirectional long short-term memory (Bi LSTM) for high-speed rolling decision making, with the outputs adjusted by a power correction balance algorithm. Finally, the validity of the model and algorithm of this paper are verified by arithmetic case analysis. [ABSTRACT FROM AUTHOR]

Hyperglycemia and metabolic syndrome (MetS) are common in patients with major depressive disorder (MDD). This study aimed to explore the prevalence and clinical factors of MetS in first-episode and drug-naïve MDD (FEDND) patients with and without hyperglycemia. A total of 1,718 FEDND patients' symptoms were assessed using the Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), and positive subscale of the Positive and Negative Syndrome Scale (PANSS). Blood glucose levels, metabolic index, and thyroid hormones were measured during fasting. The prevalence of MetS in FEDND patients with hyperglycemia was 35.67 times higher than in FEDND patients without hyperglycemia. FEDND patients with MetS were older, had later age of onset, and were predominantly married than those without MetS (p < 0.05). Among FEDND patients without hyperglycemia, suicide attempts, severe anxiety, HAMD, HAMA, PANSS subscale scores, thyroid stimulating hormone, antithyroglobulin, and total cholesterol levels were all higher in patients with MetS than those without MetS (all p < 0.05). In FEDND patients without hyperglycemia, the combination of age and TgAb distinguished those patients with and without MetS. Our results suggest a high prevalence of MetS in FEDND patients with hyperglycemia. Several clinical variables and thyroid function-related hormones impact MetS in patients with FEDND. [ABSTRACT FROM AUTHOR]

It is well-known that structures composed of super high-rise buildings accumulate damages gradually due to ultra-long loads, material aging, and component defects. Thus, the bearing capacity of the structures can be significantly decreased. In addition, these effects may cause inestimable life and property losses upon strong winds, earthquakes, and other heavy loads. Hence, it is necessary to develop real-time health monitoring methods for super high-rise buildings to deeply understand the running state during operation, timely discover potential safety potentials, and to provide reference data for reinforcement design. Along these lines, in this work, the built super high-rise buildings (Yunding Building) and super high-rise buildings (the Main Tower of the Shandong International Financial Center), under construction, were selected as the research objects. The overall dynamic deformation laws of super high-rise buildings were monitored by using ground-based real aperture radar (GB-RAR) technology for its advantages in non-contact measurement, remote monitoring, and real-time display of observation results. Denoising of the observation data was also carried out based on wavelet analysis. The visualization of the space state of the Yunding Building was realized based on handheld LiDAR technology. From the acquired results, it was demonstrated that the measuring accuracy of GB-RAR could reach the submillimeter level, while the noises under a natural state of wavelet analysis were eliminated well. The maximum deformation values of the Yunding Building and the Main Tower of Shandong International Financial Center under their natural state were 9.63 mm and 16.46 mm, respectively. Under sudden wind loads, the maximum deformation of the Yunding Building could be as high as 895.79 mm. The overall motion state switched between an S-shaped pattern, hyperbolic-type, and oblique line, presented the characteristics of nonlinear elastic deformation. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of FeCr 2 VW x (x = 0, 0.1, 0.3, 0.5) medium-entropy alloys (MEAs) manufactured using arc melting under an argon atmosphere were investigated. The investigated FeCr 2 VW x (x = 0, 0.1, 0.3) MEAs exhibited a dual-phase microstructure consisting of body-centred-cubic (BCC) phases. With the further addition of W, additional W-rich phase formed in the microstructure of the FeCr 2 VW 0.5 sample. Compression tests at the ambient and elevated temperatures revealed that the compressive performance of the MEAs improved with the introduction of W. Among them, FeCr 2 VW 0.3 demonstrated an exceptional combination of enhanced strength and ductility, showing the yield strength of 1452 MPa at ambient temperature and 627 MPa at 1223 K as well as compression reduction over 30% at both temperatures. These compressive properties are comparable to those of existing low activation refractory high-entropy alloys. The excellent high-temperature performance was attributed to the enhanced strengthening effects of precipitation and solid-solution resulting from W addition. Moreover, it was found that during the hot deformation process FeCr 2 VW x MEAs with higher W contents (above 0.3) resulted in more work hardening than that of the lower W contents, and required more dynamic recrystallization to achieve the dynamic equilibrium. These results provide valuable insights for the future development and microstructural engineering of new MEAs. • Microstructure and mechanical properties at room and high temperatures of novel low-activation high-entropy alloys, FeCr 2 VWx (x = 0, 0.1, 0.3, 0.5), were studied. • The effect of W alloying on the microstructure and hot compression properties of the prepared alloys were revealed. • FeCr 2 VW 0.3 showed superior strength at both ambient and elevated temperatures, attributed to the combined effects of precipitation and solid solution strengthening. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the associations of pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) with anogenital distance (AGD) among newborns. Methods: The study included 556 mother-newborn pairs from the Jiashan birth cohort. AGD was measured as AGDAP (from the center of the anus to the anterior base of the penis, where the penile tissue meets the pubic bone) and AGDAS (from the center of the anus to the posterior base of the scrotum, where the skin changes from rugate to smooth) in males and AGDAC (from the center of the anus to the clitoris) and AGDAF (from the center of the anus to the posterior convergence of the fourchette) in females. Multiple linear regression models were used to estimate the associations of pre-pregnancy BMI and GWG, with AGD. Results: After adjusting for pre-pregnancy BMI and other potential confounders, male newborns whose mothers had excessive GWG had shorter AGDAP than those whose mothers had normal GWG. Male newborns whose mothers had normal pre-pregnancy BMI and inadequate/excessive GWG had shorter AGDAP than the reference group where mothers had normal pre-pregnancy BMI and GWG in stratified analyses. Conclusion: Gestational weight gain during pregnancy was associated with AGD in newborns in this birth cohort. Plain language summary: In China, the prevalence of underweight and overweight/obesity remained high among women. Appropriate pre-pregnancy body mass index (BMI) and gestation weight gain (GWG) were critical to reduce the risk of adverse birth outcomes. The anogenital distance (AGD) was measured as an indicator of neonatal reproductive function and was associated with adverse reproductive outcomes in adults. Thus, we investigated the associations of both sub-optimal pre-pregnancy BMI, as well as GWG, with AGD among newborns to draw a picture about their effect on offspring reproductive health. A total of 556 mother-newborns were included in the study from the Jiashan birth cohort in China. We extracted information about maternal lifestyles, social demographic characteristics, diet, and medical history from questionnaires conducted during 8–16 gestational weeks and medical records. AGD among newborns was measured within 3 days of delivery. We found that maternal excessive GWG was associated with shorter AGD in male newborns after adjusting for maternal pre-pregnancy BMI in multiple linear regression models. The study also suggested that maternal inadequate GWG was associated with a shorter AGD in male newborns, which needed to be corroborated in further studies with a larger sample size. In conclusion, health professionals shall implement sufficient intervention to prevent suboptimal GWG during prenatal checkups. [ABSTRACT FROM AUTHOR]

We consider the broad class of decentralized optimal resource allocation problems in wireless networks, which can be formulated as a constrained statistical learning problems with a localized information structure. We develop the use of Aggregation Graph Neural Networks (Agg-GNNs), which process a sequence of delayed and potentially asynchronous graph aggregated state information obtained locally at each transmitter from multi-hop neighbors. We further utilize model-free primal-dual learning methods to optimize performance subject to constraints in the presence of delay and asynchrony inherent to decentralized networks. We demonstrate a permutation equivariance property of the resulting resource allocation policy that can be shown to facilitate transference to dynamic network configurations. The proposed framework is validated with numerical simulations that exhibit superior performance to baseline strategies. [ABSTRACT FROM AUTHOR]

Living in the same household exposes family members to shared environments and may be reflected in estimates of shared environment in twin analyses. The age at the separation of cotwins in a twin pair marks the end of such shared exposure, and the age of separation is commonly self-reported in studies. The objective of the study was to summarize the age at separation from residential records and use it to validate with self-reported separation status and age at the third and fourth wave of data collection in the FinnTwin12 cohort. Age at separation was generated from the address information, linking it to the Finnish Population information system since birth. Descriptive statistics by sex and zygosity are presented. The mean age at separation from residential records was 20.36 years old. Women separated earlier than men and dizygotic pairs earlier than monozygotic pairs. We also calculated the sensitivity and specificity with the self-reported separation status at waves 3 and 4, and interrater reliability with the self-reported separation age at wave 4. Age at separation from residential records had a relatively poor agreement with the self-report. This work enables us to use a more precise and objective measure for the shared environment in future twin studies. [ABSTRACT FROM AUTHOR]

The accuracy of locating acoustic emission (AE) source location is closely related to the reasonability of the adopted wave velocity model. However, it is literally hard to obtain an accurate wave velocity model for a heterogeneous rock material due to its inner invisible inclusions and local defects, making the AE source localization very challenging. To obtain a more appropriate wave velocity model for the heterogeneous rock material having unknown inclusions, in this study the projective reconstruction method (PRM) was utilized to determine the wave velocity model. Because the PRM is irrelevant to the continuous assumption, the proposed wave velocity model can well reflect the discontinuous characteristics of the real wave velocity field in rock materials. Then, the proposed wave velocity model was incorporated into an arrival time-based governing equation to locate the AE source. To demonstrate the effectiveness of the proposed method in improving the AE source location accuracy and monitoring the rock failure process, lead-break tests and three-point bending tests were conducted on the composite rock and rock-like specimens, respectively. Results show that the improved wave velocity model obtained by the PRM can significantly improve the accuracy of AE source location in the heterogeneous rock material with unknown inclusions. [ABSTRACT FROM AUTHOR]

Objective: Limited by spherical focused ultrasound transducer (SUT) with a high acoustic numerical aperture, photoacoustic microscopy (PAM) suffers a rapidly degrading sensitivity and lateral resolution as increased depth. In this study, an ellipsoidal focused ultrasound transducer (EUT) was developed to address the above restriction via providing high sensitivity and lateral resolution over a large depth of field (DOF). Methods: To fabricate the EUT, the piezoelectric element was laminated onto a curved steel surface for self-focusing (the ellipsoidal continuous-focus geometry was employed instead of the spherical single-focus one). Additionally, phantoms and in vivo animal experiments were performed by an extend-focus PAM equipped with EUT to characterize its performance. Results: The EUT involved over 30 MHz center frequency and -6 dB bandwidth of 124% with a resolution-invariant focal depth of 1.39 mm, more than 3 times the DOF of the SUT. Conclusion: The in vivo imaging results demonstrated that the EUT was capable of extending the focal depth to get rid of the restriction of the visual field, while the DOF of the SUT was limited by the nature of spherical geometry. Significance: The EUT markedly enhances the image quality at different imaging depths, which has great potential for promoting the biomedical development of in vivo rapid-noninvasive PAM. [ABSTRACT FROM AUTHOR]

Multi-view subspace clustering (MVSC) finds a shared structure in latent low-dimensional subspaces of multi-view data to enhance clustering performance. Nonetheless, we observe that most existing MVSC methods neglect the diversity in multi-view data by considering only the common knowledge to find a shared structure either directly or by merging different similarity matrices learned for each view. In the presence of noise, this predefined shared structure becomes a biased representation of the different views. Thus, in this article, we propose a MVSC method based on coupled low-rank representation to address the above limitation. Our method first obtains a low-rank representation for each view, constrained to be a linear combination of the view-specific representation and the shared representation by simultaneously encouraging the sparsity of view-specific one. Then, it uses the k-block diagonal regularizer to learn a manifold recovery matrix for each view through respective low-rank matrices to recover more manifold structures from them. In this way, the proposed method can find an ideal similarity matrix by approximating clustering projection matrices obtained from the recovery structures. Hence, this similarity matrix denotes our clustering structure with exactly k connected components by applying a rank constraint on the similarity matrix's relaxed Laplacian matrix to avoid spectral post-processing of the low-dimensional embedding matrix. The core of our idea is such that we introduce dynamic approximation into the low-rank representation to allow the clustering structure and the shared representation to guide each other to learn cleaner low-rank matrices that would lead to a better clustering structure. Therefore, our approach is notably different from existing methods in which the local manifold structure of data is captured in advance. Extensive experiments on six benchmark datasets show that our method outperforms 10 similar state-of-the-art compared methods in six evaluation metrics. [ABSTRACT FROM AUTHOR]

The finite-difference (FD) scheme is extensively applied in seismic modelling, imaging and inversion due to its advantages of large-scale parallel computing and programming. However, numerical dispersion caused by using a difference operator in substitution for the differential operator is non-negligible, which reduces the accuracy of the modelling and can lead to some misinterpretations. In addition, the computing resources required by the FD scheme is highly demanding when dealing with large models, which limits its applicability. In this paper, a new optimised FD scheme is proposed, which is based on an improved particle swarm optimisation (PSO) algorithm. We improve the conventional PSO algorithm by introducing strategies related to local learning and global learning, which contribute to accelerating the convergence rate and effectively avoiding getting trapped in local extrema. Then, the improved PSO algorithm is used to improve the conventional FD scheme. Dispersion analysis and numerical modelling demonstrate that the low-order optimised FD scheme can achieve higher accuracy than a high-order conventional operator. Compared with the conventional FD scheme and a FD scheme based on the Remez exchange algorithm, the optimised FD scheme based on the improved PSO algorithm can more efficiently suppress numerical dispersion and increase computational efficiency. [ABSTRACT FROM AUTHOR]

The doping of luminescent semiconductor nanoparticles has been a hotspot of research, especially rare earth element doped Nano-fluorescent material as a result of their distinct electronic structures. Herein, the investigation of the Ce3+ doping content effect on the UV–vis absorption, electronic structures, luminescence decay, and photoluminescence of SnS is one of crucial orientations of this. In this work, a reproducible gas and liquid chemical deposition method is used to synthesize the SnS and SnS:Ce3+ quantum dots. It has been detected that by doping Ce3+, the photoluminescence peak SnS can be enhanced clearly and the direct bandgap energy of SnS:Ce3+ quantum dots has gradually decreased, which indicates doping Ce3+ can effectively control the optical properties of SnS. The lifetime values of SnS:Ce3+ quantum dots has significantly shorten in comparison to the pure SnS and due to the overlapped energy levels of Ce3+ and Sn2+, the luminescence of SnS quantum dots will improve. By using the first principles of density functional theory (DFT), we calculated the total density of states (TDOS), the band structure and the partial densities of states (PDOS) of SnS and SnS:Ce3+ structures. The aforesaid experimental results have been attested by the calculating results exactly. • SnS:Ce3+ QDs are synthesized by a gas-liquid phase chemical deposition method. • Ce atoms provide a new energy level which can enhance the luminescence of SnS. • The lifetime values of SnS:Ce3+ have shrunk in comparison to the pure SnS. [ABSTRACT FROM AUTHOR]

This study develops a generalized additional voltage pumping solution (GAVPS) for a series of high-step-up converters, whose topologies can be modeled by a generalized architecture. The newly designed converters can achieve additional voltage pumping by only applying an additional diode and capacitor to the conventional high step-up converter structure. Integrating the proposed solution into the existing high-step-up converters, five typical case studies with corresponding analyses and comparisons are conducted and presented, which verifies the proposed voltage pumping strategy. Additionally, five prototypes are built in this study, and the experimental results further validate the effectiveness of the proposed GAVPS solution. The proposed strategy in theory will work synergistically with all types of dc–dc converters, which demonstrates its unparalleled significance in expanding its applicability in contemporary power converter industries. [ABSTRACT FROM AUTHOR]

Understanding evolutionary dynamics of population structure and genetic diversity of marine fish species is of great importance for fishery management and resource conservation. Platycephalus sp.1 is a commercially important marine fish in the Northwestern Pacific. Yet, current understanding of population genetic patterns of Platycephalus sp.1 remains limited. In this study, the Platycephalus sp.1 individuals from four populations in the Northwestern Pacific, which cover large geographic distances and latitudinal gradients, were sampled to examine genetic diversity and population structure by investigating the mitochondrial sequences of Cytochrome b (CYTB, 1141 bp) and control region (CR, 458 bp), and then to assess intra-mitochondrial genetic variability by using a combination of population- and individual-based analytical approaches. Moderate to low levels of genetic diversity were observed in sampled populations by investigating both CR and CYTB datasets. In CR dataset, weak genetic differentiation among populations were observed and population Tokyo Bay was significantly differentiated with other sampled populations. In CYTB dataset, lower genetic differentiations were observed and population Beihai (BH) was significantly differentiated. A non-synonymous substitution was predominantly detected in population BH, and such substitution was tested as a significantly positive selective site in natural selection tests. Based on these findings, we propose that local adaptation influenced by natural selection contributes largely to the intra-mitochondrial variation in Platycephalus sp.1 populations. The present study provides new perspectives on the population genetic structure of Platycephalus sp.1, which could have important implications for the sound management and conservation of this fishery species. [ABSTRACT FROM AUTHOR]

In order to study the genetic diversity of Thamnaconus modestus, a species of great commercial importance in Southeast Asia, the 5′-end hypervariable regions (423 bp) of the mitochondrial control region of T. modestus in nine geographical populations (248 individuals) were sequenced and analysed in this study. The target sequence fragment contained large numbers of polymorphic sites (87) involved in high levels of haplotype diversity (h = 0.97 ± 0.01) and nucleotide diversity (π = 0.0285 ± 0.0143). The genetic variations within populations (92.71%) were significantly larger than those among populations (7.29%). No significant genetic divergences were detected among the wild populations owing to their gregarious habits, strong moving ability, r-selection strategy. Significant genetic divergences were found between the cultured and wild populations, probably resulting from kin selection and aquacultural environment. Three significant phylogenetic lineages were identified, and the variation among lineages (56.90%) was greater than that among individuals within the lineages (43.10%), with the significant ΦST value (ΦST = 0.57, P = 0.0000). The results showed great and significant genetic differentiations among these three lineages, indicating that they may have independent phylogenetic dynamics. Dominant shared haplotypes that included individuals from each population and the median-joining network of haplotypes presented a star-like structure. Historic demographic analysis of each lineage showed that population expansion occurred after the Pleistocene glacial period. At the last glacial maximum, T. modestus in China seas was scattered across variable refuges, including Central South China Sea and Okinawa Trough. [ABSTRACT FROM AUTHOR]

We consider a variant of the classic multi-armed bandit problem where the expected reward of each arm is a function of an unknown parameter. The arms are divided into different groups, each of which has a common parameter. Therefore, when the player selects an arm at each time slot, information of other arms in the same group is also revealed. This regional bandit model naturally bridges the classical non-informative bandit setting where the player can only learn the chosen arm, and the global bandit model where sampling one arm reveals information of all arms. We propose an efficient algorithm, UCB-g, that solves the regional bandit model by combining the Upper Confidence Bound (UCB) and greedy principles. Both parameter-dependent and parameter-free regret upper bounds are derived. We also establish a matching lower bound, which proves the order optimality of UCB-g. Moreover, we propose SW-UCB-g, which is an extension of UCB-g for a non-stationary environment where the parameters vary over time. [ABSTRACT FROM AUTHOR]

We experimentally demonstrate a method for long distance measurement using optical sampling by sweeping the repetition frequency of the frequency comb. The interferograms can be obtained by continuously changing the repetition frequency, and the distances can be determined via the peak position of the interferograms. Compared with the fringe counting interferometer, the experimental results show an agreement within ±3 µm in 75 m range. [ABSTRACT FROM AUTHOR]

The traditional switched-inductor technique for high-step-up conversion is widely utilized in industrial applications, especially multicell technique is combined to realize ultra-high voltage. However, the component currents are accordingly increasing with the increasing number of cells, which results in high cost, low efficiency, and low stability. In order to solve these problems, an improved multicell structure of switched inductor is devised, which can be utilized to replace traditional switched-inductor cells for higher actual boost ratio and lower diode currents. An example of the proposed structure-based boost converter is demonstrated for a detailed analysis, and it is followed with a comparison to verify its features. Finally, simulations and experiments are conducted to validate the effectiveness. [ABSTRACT FROM AUTHOR]

To promote accurate lattice‐strain measurement and twinning observation during in situ deformation of age‐hardenable lightweight magnesium alloys, a high‐resolution X‐ray diffraction technique was applied using medium‐energy synchrotron X‐rays (≤21 keV) coupled with a fast Mythen strip detector. This technique allows data collection in transmission geometry, with sufficient grain‐sampling statistics achieved by rocking the samples during each measurement under step‐wise uniaxial tensile/compressive loads. The capabilities of the method are demonstrated on a model age‐hardenable Mg–Sn‐based alloy in compression. The measurements confirm that this technique offers high angular resolution and a wide angular range, minimizing the problem of peak overlap, which is advantageous for accurate lattice‐strain determination of both the α‐Mg matrix and strengthening precipitate phases. The absolute strain resolution is approximately ±2 × 10−4. Lattice‐strain partitioning and anisotropy in the α‐Mg phase reveal the occurrence of microplasticity due to the activation of basal dislocation slip in Mg alloys and provide experimental information for characterizing the plastic anisotropy of the materials. The initiation and growth of { } tension twins are identified and quantified from the changes in the integrated intensities of reflections as a function of stress. The critical resolved shear stresses (CRSSs) for the activations of basal slip and tension twin modes in both non‐aged and aged materials were estimated. The results reveal that, after the ageing treatment, the CRSS value for basal slip increases from 18 to 33 MPa, an increase of ∼83%, and that for tension twinning increases from 32 to 52 MPa, an increase of ∼63%. The methodology also enables further microstructural data to be probed in situ. This includes the apparent area‐weighted twin size and dislocation density during twin onset, and the precipitate volume fraction. [ABSTRACT FROM AUTHOR]

The medium entropy alloys (MEAs) composed of high-melting-point, low-activation elements often demonstrate favorable mechanical properties and reduced activation required for nuclear applications. In this work, novel low activation MEAs of FeCr 2 V and FeCr 2 VW 0.1 as potential nuclear structural materials have been developed. Thermodynamic calculation was used to guide the MEA design. The materials were fabricated using arc melting and their microstructure and mechanical properties were investigated. The results show that the developed MEAs are characterized by a dual-phase microstructure consisting of both body-centered-cubic (BCC) phases. The as-fabricated FeCr 2 VW 0.1 exhibits improved hardness (average nano-hardness 9.6 GPa) compared with FeCr 2 V (7.4 GPa), owing to the enhanced solid solution strengthening (SSS) and precipitation strengthening (PS). Meanwhile, after doping with W, the compressive ultimate strength and yield strength of MEAs increased by about 15.7 % and 13.7 %, respectively. Being quantitatively consistent with the experimental results, the first-principles calculations based on the density functional theory (DFT) and the theoretical strengthening calculations confirmed that the W doping into FeCr 2 V based MEA significantly enhanced the SSS and PS in the studied alloy. The results provide insights that are useful for future development and microstructural engineering of these novel MEAs. • Novel medium entropy alloys (MEAs) of FeCr 2 V and FeCr 2 VW 0.1 for potential nuclear applications were developed by combining thermodynamics calculations and experimental verifications. • The developed MEAs exhibit a dual-BCC-phase microstructure and superior mechanical property. • The W doping effectively enhances the mechanical property of FeCr 2 V alloy by the precipitation and solid solution hardening. [ABSTRACT FROM AUTHOR]

Using 4-hydroxybutyl vinyl polyoxyethylene ether (VPEG) as macromonomer, acrylic acid (AA), methacrylic acid (MAA) and sodium methallyl sulfonate (SMAS) as comonomers, and thioglycolic acid (TGA) as chain transfer agent, VPEG-viscosity-reducing polycarboxylate superplasticizer PCE-J was synthesized by free radical polymerization under the redox initiation system composed of H2O2/vitamin C (VC). The effects of synthesis process condition on the properties of the synthesized superplasticizer were investigated. The most suitable synthesis process condition was obtained as follows. The reaction temperature was 20 °C. The ratio of acid to ether was 3.5:1. The amount of SMAS, MAA, H2O2 and TGA was 0.1 wt%, 2 wt%, 0.7 wt% and 0.6 wt% of VPEG, respectively, and the addition time of A and B was 30 min and 40 min, respectively. The PCE-J and the commercially available viscosity-reducing superplasticizer PCE-S were compared and analyzed in terms of cement paste fluidity, concrete viscosity reduction performance (T50 time, emptying time) and cement test block strength performance. It is concluded that PCE-J has excellent dispersion performance for cement, cement paste fluidity is as high as 305 mm, and has excellent viscosity reduction effect on concrete. The concrete emptying time and T50 time are 4.1 s and 5.7 s, respectively, which can significantly improve the compressive strength of cement test blocks. The compressive strength of 28 d cement test blocks is as high as 67.1 MPa. [ABSTRACT FROM AUTHOR]

Since BiSrCa1CuO(Bi2212) wires are subject to mechanical loadings, degradation of critical current will occur. The effect of compressive loadings on the critical current of Bi2212 wire is studied by considering micro-buckling of filament. A Bi2212 wire is regarded as a unidirectional filament-reinforced composite in the theoretical analysis. By considering the influence of inclusion, the micro-buckling wavelength can be derived by using a two-dimensional model. Based on the experimental results, the critical current is fitted as a function of buckling wavelength. It is found that the decrease of the critical current is directly proportional to the reciprocal of square of the buckling wavelength. Change of micro-buckling wavelength with material parameters is discussed. A critical strain in the wire with a filament bridge is analyzed using the finite element method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pairing n -type electrochromic polymer with p-type electrochromic polymers to give black-to-transmissive switching. • COMSOL modeling to streamline the device optimization. • High optical contrast and coloration efficiency. • General guidelines to design and prepare dual electrochromic devices. In a complementary electrochromic device (ECD), both the anode and the cathode can synergistically change color in response to an electrical bias, allowing for a high coloration efficiency. Complementary ECD that can switch from black to transmissive state is rare, due to the difficulty of pairing two electrochromic electrodes. In this study, we report the construction of high coloration efficiency complementary ECDs by pairing polyazoisoindigo (PAI), an n -type electrochromic polymer that undergoes green-to-transmissive switching, with p-type magenta (ECP-M) and red (ECP-R) electrochromic polymers to obtain black-to-transmissive ECD. Physical modeling tool, COMSOL, is introduced for complementary color matching. Through balancing the charge densities of two electrochromic electrodes, black-to-transmissive ECDs with record-high coloration efficiencies of 688 cm2/C and 437 cm2/C have been achieved for PAI|ECP-M and PAI|ECP-R, respectively. This study provides a general protocol for the design and fabrication of complementary ECDs. [ABSTRACT FROM AUTHOR]

In this study, a Ni-based Hastelloy C276 alloy was prepared using cold metal transfer (CMT)-based directed energy deposition (DED) under different heat inputs with a zig-zag deposition path, integrated with active cooling and interlayer temperature control. Analogous mechanical properties were obtained for the fabricated alloys under different heat inputs (276, 368 and 553 J/mm) through effective interlayer temperature control. Such a broad processing window facilitates the large-scale industrial manufacturing and application of Hastelloy C276 by DED. Nevertheless, the lower heat input appears to slightly refine the microstructure and decrease the mechanical anisotropy of manufactured alloys, which is ascribed to combined effects of the manipulated bulk texture, refined dendrite arm spacing and reduced chemical segregation under lower heat input. Despite the variations of geometrically necessary dislocation (GND) densities with heat inputs, no significant change was observed in the average total dislocation density (TDD) in the microstructure of all samples as suggested by the peak profile analysis of Synchrotron X-ray diffraction data, which is advantageous for lowering the solidification cracking susceptibility. Moreover, all as-fabricated alloys present a typical strong fibre-type (200) crystallographic bulk texture measured by neutron diffraction, while such texture was relatively weaker in the lowest heat input condition. This work provides a reliable approach for stable additive manufacturing of Hastelloy C276 alloy, and innovatively presents rationales of stabilised properties based on the obtained insights into microstructure and bulk texture developments in a wide observation range by various techniques. [ABSTRACT FROM AUTHOR]

How to understand individual human actions is a fundamental question to modern science, which drives and incurs many social, technological, racial, religious and economic phenomena. Human dynamics tries to reveal the temporal pattern and internal mechanism of human actions in letter or electronic communications, from the perspective of continuous interactions among friends or acquaintances. For interactions between stranger to stranger, taxi industry provide fruitful phenomina and evidence to investigate the action decisions. In fact, one striking disturbing events commonly reported in taxi industry is passenger refusing or denial, whose reasons vary, including skin color, blind passenger, being a foreigner or too close destination, religion reasons and anti specific nationality, so that complaints about taxi passenger refusing have to be concerned and processed carefully by local governments. But more universal factors for this phenomena are of great significance, which might be fulfilled by big data research to obtain novel insights in this question. In this paper, we demonstrate the big data analytics application in revealing novel insights from massive taxi trace data, which, for the first time, validates the passengers denial in taxi industry and estimates the denial ratio in Beijing city. We first quantify the income differentiation facts among taxi drivers. Then we find out that choosing the drop-off places also contributes to the high income for taxi drivers, compared to the previous explanation of mobility intelligence. Moreover, we propose the pick-up, drop-off and grid diversity concepts and related diversity analysis suggest that, high income taxi drivers will deny passengers in some situations, so as to choose the passengers’ destination they prefer. Finally we design an estimation method for denial ratio and infer that high income taxi drivers will deny passengers with 8.52% likelihood in Beijing. Our work exhibits the power of big data analysis in revealing some dark side investigation. [ABSTRACT FROM AUTHOR]

The Last Glacial Maximum climate, which severely influenced the sea level, surface water temperature and currents, combining with present marine environment and life historical characteristics, could mainly determine the phylogeographical pattern of marine species in the East China Sea and the South China Sea. Thamnaconus hypargyreus is a commercially important but intensively exploited species in the South China Sea and the East China Sea, and morphological studies indicated population variations between these two seas. Hence in our study, the control region segment of mitochondrial DNA was sequenced to detect the genetic diversity, mitochondrial phylogeographical pattern and genetic connectivity of T. hypargyreus in the South China Sea and the East China Sea. The results indicated high levels of control region diversity, lack of significant phylogeographical structure and historical population expansion after the Pleistocene. The Last Glacial Maximum marine environment, the present ocean currents and life history with high dispersal potential should be responsible for high levels of genetic connectivity among the analyzed populations and shallow phylogeographical pattern. Baselines on the genetic structure and genetic diversity would be essential for the effective conservation and sustainable fishery management. [ABSTRACT FROM AUTHOR]

In this paper, to study the influence of grouting on meso-failure mechanism, acoustic emission (AE) localization technique was used to monitor the micro-cracking during the uniaxial compression tests on single flawed sandstone specimens with or without grouting. Due to the inhomogeneous geometrical structure of the flawed specimens, the mesoscopic damage evolution is also inhomogeneous during the loading process. As a result, the wave velocity of the specimens varied temporally and spatially, which greatly increased the difficulty in accurate AE localization. To solve this problem, the wave velocities versus the axial load for the studied sandstone were first measured, and the stress concentration effect near the flaw was also theoretically analyzed. Accordingly, the localization arithmetic was also improved to match the complex wave velocity field. Results show that compared to the specimens without grouting, more microcracks (particularly the shear microcracks) are induced in the grout-infilled specimens prior to the final failure of the specimens. Moreover, the effect of grouting on microcrack initiation also varies with the oblique angle of the flaw. For θ (flaw inclination) ≤30°, grouting significantly increases the shear microcrack at macrocrack propagation stage which states that the axial tensile cracking was limited by the supporting effect of the grout material and made the failure mode trend to shear mode. For θ = 45° and 60°, grouting improved the ratio of shear microcrack during the whole failure process, indicating that the direction of maximum shear stress is close to the flaw direction. Hence, failure develops in stable shear mode. For θ = 75° and 90°, the primary microcrack generated during the first macrocrack initiation changed to shear mode, but the grouting has little influence on the subsequent crack propagation. So that, the reinforcement effect is poor in this set of specimens. • The AE localization technique was improved by adopting a temporally and spatially varied wave velocity model. • Grouting decreases the stress concentration near the prefabricated flaw, which changes the mechanism of crack evolution. • The development of a macro crack in the flawed specimen follows a tensile-shear-alternating meso damage evolution mode. [ABSTRACT FROM AUTHOR]

The phase evolution in a zirconium–50 deuterium (Zr–50D, at.%) alloy system during thermal cycling has been investigated using in situ high-resolution neutron powder diffraction. The results showed that the peritectoid reaction α-Zr + δ-ZrD → γ-ZrD previously suggested to occur at high temperatures does not take place in the system. Slow cooling, from high temperatures (≥520 K) to room temperature at a rate of 5 K min −1 , promoted the γ-hydride formation rather than fast cooling as reported earlier. In contrast to the observation that the δ-hydride present in the system remained at temperatures up to 740 K, the produced γ phase transformed to δ-hydride in the temperature range of 370 K–559 K, with the transformation completing at approximately 559 K. It is confirmed that the formation of the γ-hydride was reproducible with slow cooling, and a diffusion-controlled sluggish δ-to γ-hydride transformation is suggested to be responsible for the favorable development of γ-hydride during slow cooling. [ABSTRACT FROM AUTHOR]

As the plunger pump always works in a complicated environment and the hydraulic cycle has an intrinsic fluid-structure interaction character, the fault information is submerged in the noise and the disturbance impact signals. For the fault diagnosis of the bearings in plunger pump, an optimum intrinsic mode functions (IMFs) selection based envelope analysis was proposed. Firstly, the Wigner-Ville distribution was calculated for the acquired vibration signals, and the resonance frequency brought on by fault was obtained. Secondly, the empirical mode decomposition (EMD) was employed for the vibration signal, and the optimum IMFs and the filter bandwidth were selected according to the Wigner-Ville distribution. Finally, the envelope analysis was utilized for the selected IMFs filtered by the band pass filter, and the fault type was recognized by compared with the bearing character frequencies. For the two modes, inner race fault and compound fault in the inner race and roller of rolling element bearing in plunger pump, the experiments show that a promising result is achieved. [ABSTRACT FROM AUTHOR]

In situ rock mass usually contains discontinuities in various forms, including fissures, joints and fractures, etc., and it becomes more heterogeneous when the discontinuities are backfilled with artificial grouting. It is incredibly challenging to obtain an accurate wave velocity model for those rocks with random inclusions, making the AE sources more difficult to locate. This study first proposed a projective reconstruction method (PRM) to obtain the wave velocity model for heterogeneous rock. An improved AE source localization algorithm was proposed using the arrival time-based governing equations. Flawed sandstone samples with various inclination angles were then prepared and subjected to unconfined compression until failure. The fragments were restored to generate post-grouted samples with random inclusions. The feasibility and validation of the PRM-based wave velocity model and the proposed AE source localization algorithm were verified by pencil lead break tests. The AE source localization results were compared using three wave velocity models, i.e., averaged wave velocity model, 1D approximated wave velocity model and PRM-based wave velocity model. The results indicate that the PRM-based AE source localization for the post-grouted samples is much more accurate than the other two models. Finally, the fracturing mechanisms of the post-grouted samples with random inclusions under uniaxial compression conditions were illuminated based on the results of the AE source localization and moment tensor inversion. It is confirmed that the PRM-based wave velocity model was promising for the AE source localization in heterogeneous rocks with random inclusions. Highlights: A projective reconstruction method for obtaining the wave velocity field of heterogeneous rocks. More accurate AE source localization was achieved for post-grouted sandstones with random inclusions. The proposed PRM-based wave velocity model are promising for microseismic localization application in the practical field. [ABSTRACT FROM AUTHOR]

A nano-grained microstructure of an α-Zr alloy (Zircaloy-4) was produced by high-pressure torsion, which shows evidence of a metastable ω-Zr phase, rather than β-Zr, determined by combining synchrotron X-ray diffraction and detailed electron microscopy observations. The ω-Zr phase is retained at ambient conditions and shows a new orientation relationship of [ 1 ¯ 011 ] α // [ 1 ¯ 100 ] ω and (1 ¯ 01 1 ¯) α // (1 ¯ 1 ¯ 20) ω with the α-Zr matrix but is thermally unstable, fully reverting back to α-Zr phase upon heating above 350 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The hydride formation and its influence on the mechanical performance of hydrided Zircaloy-4 plates containing different hydrogen contents were studied at room temperature. For the unnotched plate samples with the hydrogen contents ranging from 25 to 850wt.ppm, the hydrides exerted an insignificant effect on the tensile strength, while the ductility was severely degraded with increasing hydrogen content. The fracture mode and degree of embrittlement were strongly related to the hydrogen content. When the hydrogen content reached a level of 850wt.ppm, the plate exhibited negligible ductility, resulting in almost completely brittle behavior. For the hydrided notched plate, the tensile stress concentration associated with the notch tip facilitated the hydride accumulation at the region near the notch tip and the premature crack propagation through the hydride fracture during hydriding. The final brittle through-thickness failure for this notched sample was mainly attributed to the formation of a continuous hydride network on the thickness section and the obtained very high hydrogen concentration (estimated to be 1965wt.ppm). [Copyright &y& Elsevier]

An energy-storage flywheel consists of a large inertia wheel sharing a common shaft with a motor generator (MG) set and with magnetic bearings to support the entire rotating assembly. Flywheels mounted on a special slug car are charged from the local utility grid and from regenerative-braking events. Usage of these power sources reduces fuel consumption and the related NOx emission by the locomotive-mounted Diesel generator sets (DGS). The flywheel-supplied power can replace the DGS-supplied power in one or more of the eight fixed power settings (notches), plus idle and reverse, which are common to most locomotives either for line-haul or switchyard service. The slug cars have separate traction motors to be driven by the flywheel systems so that the flywheel power and DGS power are electrically and physically decoupled. A system model is presented that includes the train dynamics coupled with the electromechanical models for the flywheels and traction motors. The modified Davis equation is employed in the train model to account for windage and other losses. A novel, feedback-based flux-weakening control of the flywheel's motor generator current-torque and speed-back electromotive force (emf) gain is employed to increase the charge capacity, depth of discharge, and regenerative-braking efficiency for the flywheels. The simulation results show significant cost- and emissions-reduction potential for the proposed hybrid DGS-flywheel locomotive power system in line-haul and switcher service. [ABSTRACT FROM AUTHOR]

The gaseous hydriding-induced evolutions of the microstructure, texture and mechanical properties of Zircaloy-4 processed by high-pressure torsion (HPT) were assessed. Much δ-ZrH1.66 precipitation at 15atm (21%) incurred significant hardening of vacuum-annealed HPT samples, and pure ε-ZrH2 obtained at 20atm showed a superior microhardness of 470 HV0.3 and a low fracture toughness of 0.63MPam1/2. The δ-hydrides presented strong (111) texture and followed the (0001)α-Zr//{111}δ-ZrH1.66 orientation relationship with the α-Zr matrix. During hydriding, α-Zr recrystallization texture was developed from the initial deformation texture. [Copyright &y& Elsevier]

This paper illustrates the significance of the purity of cyclostationary signals and presents a new method for blind extraction of these signals. The advantage of the method can not only extract the cyclostationary signals from low order to high order in turn but also perform algorithm without knowing cyclic frequencies of the extracted signals. The effectiveness of the proposed method is finally demonstrated by computer simulations and experiments. [ABSTRACT FROM PUBLISHER]

Abstract: The original and high-pressure torsion (HPT) processed Zircaloy-4 materials were hydrided using gaseous hydrogen charging at different hydrogen pressures (10, 15 and 20atm). The phase and microstructural evolutions of the samples during hydriding were characterized. It showed that when hydriding at the identical conditions, more hydrides tended to form in the HPT samples compared to that of the original ones. At a hydrogen pressure of 20atm, the HPT sample was completely converted to ε-ZrH2 while some δ-ZrH1.66 hydrides (volume fraction ~5.73%) were present in the material without HPT preprocessing. The HPT samples exhibited high potential for the hydride precipitation, and the large concentration of lattice defects induced by HPT was considered to be responsible for this enhanced susceptibility. [Copyright &y& Elsevier]

Abstract: For machine fault diagnosis the signals from working machine are always numerous, even uncountable, but there contains only a little useful information. Hence how to find out the useful signal from numerous signals, including noises, that is, how to only extract the desired fault signal is very attractive. This paper shows that the constrained independent component analysis (cICA) can solely extract desired faulty signal using some prior mechanical information. The methods of creating reference of cICA for machine diagnostics are discussed, and the effectiveness of the method is successfully verified by simulations and experiments. [Copyright &y& Elsevier]

The long PCR and primer walking methods were applied for obtaining the complete mitochondrial genome of the tessellated leatherjacketThamnaconus tessellatus. The complete mitochondrial genome was 16,437 bp in length and contained 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, an origin of L-strand replication and a control region. The arrangements and characteristics of these segments shared common features with other teleosts. Extended termination associated sequence domain (TAS, cTAS), central conserved sequence block domain (CSB-F, CSB-E, CSB-D) and conserved sequence block domain (CSB-1, CSB-2, CSB-3) were identified in the control region. [ABSTRACT FROM AUTHOR]

Abstract: Mechanical alloying of Ti–Al–graphite elemental powder mixture was performed to synthesize nanocomposite powder with Ti(Al) solid solution matrix reinforced by in-situ formed TiC particles. The evolutions in phases, microstructures, and compositions of milled powders with the applied milling times were investigated. It showed that with increasing the milling time, the starting irregularly shaped powder underwent a successive change in its morphology from a flattened shape (10h) to a highly coarsened spherical one (15h) and, eventually, to a fine, equiaxed and uniform one (above 25h). The prepared TiC/Ti(Al) composite powder was nanocrystalline, with the estimated average crystallite size of ∼12nm and of ∼7nm for Ti(Al) and TiC, respectively. Formation mechanisms behind the microstructural development of powders were elucidated. The Ti(Al) solid solution is formed through a gradual and progressive solution of Al into Ti lattice. The formation of TiC is through an abrupt, exothermic, and self-sustaining reaction between Ti and C elements. Selective Laser Melting (SLM) of as-prepared TiC/Ti(Al) composite powder was performed. The TiC particle reinforced TiAl3 (a major phase) and Ti3AlC2 (a minor phase) matrix composite part was obtained after SLM. Although a slight grain growth occurred as relative to as-milled powder, the SLM processed composites still exhibited a refined microstructure. [Copyright &y& Elsevier]

Two-dimensional photonic crystals (2D PhCs) select photons by cavity resonance, and can be used to design selective filters for thermophotovoltaic (TPV) applications. Due to the broad pass band and high out-band reflectance of the 2D PhC structure, the TPV system can achieve both high power density and high efficiency. However, the absorption during cavity resonance restrains the further improvement of performance. In this article, a 2D metallic PhC layer was added on top of a one-dimensional photonic crystal filter, and the best geometric parameters were obtained. The simulation indicated that the parasitic absorption of the optimized tandem photonic crystal filter can be reduced to half of the traditional metallic 2D PhC filters. The new filter also shows a sharper cut-off edge and better in-band transmittance. Moreover, an ideal thermodynamic model was applied to estimate the performance of TPV systems with a filter. Using a 1200 ∘C blackbody emitter, the spectral efficiency of the tandem photonic crystal filter can reach 73%, and the in-band transmittance is over 80%. When optimizing the filter based on existing GaSb cells, the system power conversion efficiency can reach 28%. • The filter achieves excellent out-band reflectance and high in-band transmittance. • The tandem PhC structure significantly reduces the parasitic absorption of filters. • A simplified scheme for calculating effective radiant heat transfer in TPV systems. • The efficiency of TPV system with GaSb cell can be expected to be 28% at 1473 K. [ABSTRACT FROM AUTHOR]

In this paper, we propose and numerically characterize the optical characteristics of a dual eccentric-core D-shaped photonic crystal fiber (PCF) surface plasmon resonance (SPR) refractive index (RI) sensor. The dual eccentric-core structure can leak more power to plasma film to excite SPR phenomenon than conventional structures. We investigate the influences induce by diameter of air holes, distance between air holes and thickness of gold film. The results show that our sensor has the wavelength sensitivities (WS) of 44,000 nm/RIU for odd mode and 39,000 nm/RIU for even mode. Moreover, the sensor has the detection range of RI from 1.00 to 1.37, the maximum figure-of-merit (FOM) of 325/RIU, maximum resolution of 2.27 × 10−6 RIU for analyte RI change of 0.1 nm, and the minimum full-width at half-maximum (FWHM) of 56 nm. The sensor has wide application prospects in methane, blood plasma, and methanol detecting. [ABSTRACT FROM AUTHOR]

The equivalence of absorption rates and extents between generic drugs and their reference formulations is crucial for ensuring therapeutic comparability. Bioequivalence (BE) studies are widely utilized and play a pivotal role in substantiating the approval and promotional efforts for generic drugs. Virtual BE simulation is a valuable tool for mitigating risks and guiding clinical BE studies, thereby minimizing redundant in vivo BE assessments. Herein, we successfully developed a physiologically based absorption model for virtual BE simulations, which precisely predicts the BE of the apixaban test and reference formulations. The modeling results confirm that the test and reference formulations were bioequivalent under both fasted and fed conditions, consistent with clinical studies. This highlights the efficacy of physiologically based absorption modeling as a powerful tool for formulation screening and can be adopted as a methodological and risk assessment strategy to detect potential clinical BE risks. [ABSTRACT FROM AUTHOR]

In the development of atomic physics, laser sources with Frequencies corresponding to atomic transition and high stability are essential. The Faraday laser is a special diode laser using the Faraday anomalous dispersion optical filter (FADOF) to realize frequency selection, so the output laser frequency is automatically limited to the atomic Doppler broadening. However, the frequency of a Faraday laser corresponds to the range around only one atomic hyperfine transition. Here, we realize a switchable Faraday laser with two isotopes laser frequencies corresponding to 85Rb 5 2 S 1 / 2 (F = 3) → 5 2 P 3 / 2 and 87Rb 5 2 S 1 / 2 (F = 2) → 5 2 P 3 / 2 transitions based on a single isotope 87Rb-FADOF. The laser has good robustness against the fluctuation of diode current and temperature, with wavelength fluctuating within 0.8 pm from 16 to 30 °C of diode temperature, and has a free-running linewidth of 18 kHz. We also lock the laser frequency to the two cycling transitions of 85Rb 5 2 S 1 / 2 (F = 3) → 5 2 P 3 / 2 (F ′ = 4) and 87Rb 5 2 S 1 / 2 (F = 2) → 5 2 P 3 / 2 (F ′ = 3) by the modulation transfer spectroscopy technique. The Allan deviation of the residual error signal is 3 × 10 − 14 / τ , and the frequency stability of the beat detection reaches 2.8 × 10 − 12 at 1 s integration time. This 780 nm switchable Faraday laser expands the application scenarios of Faraday lasers, which can be used in laser cooling atoms, optical frequency standards, and other quantum precision measurement fields. [ABSTRACT FROM AUTHOR]

A new Powder-bed Arc Additive Manufacturing (PAAM) processing which includes on-line remelting of deposited material has been developed for the manufacturing of high entropy alloys (HEAs) based on an existing AlCoCrFeNi 2.1 pseudo-eutectic system. The remelting process is typically applied in the arc melting process to improve the homogeneity of prepared material. We investigated the microstructure and mechanical properties of produced AlCoCrFeNi 2.1 HEA after applying a remelting process (1, 3, and 6 times) on each deposited layer. The results show the formation of the pseudo-eutectic microstructure, which consists of relatively large columnar grains of the dominant FCC phase (~90 wt%) and fine dendritic grains of the minor BCC phase (~10 wt%). The applied layer-remelting process shows negligible effects on the phase fractions and their compositions, however, it significantly degraded the tensile strength and ductility of prepared alloys. Particularly, the ductility of the alloy reduced dramatically from about 27% after one time layer-remelting to only about 3% after 3 times layer-remelting. This is rationalised by the significant localisation of thermally induced plasticity caused by repeated remelting of deposited material. We also show that this thermally induced plasticity leads to an increased amount of local misorientation in both constitute phases, which suggests an increased amount of stored dislocations in the microstructure. Despite the potentially strain hardening due to this accumulation of the thermally induced plasticity, the appreciable growth and constrained dendritic morphology of BCC grains that developed after remelting play a prevailing role on the materials strength, which limit the interfacial strengthening of the eutectic microstructure and consequently result in the loss of the tensile strength. The obtained results will assist in the further development and microstructure optimisation of novel HEAs using powder-based additive manufacturing processes. [ABSTRACT FROM AUTHOR]

Vinylidene chloride copolymer microspheres were synthesized by in situ suspension copolymerization of vinylidene chloride (VDC), methyl methacrylate (MMA), and/or acrylonitrile (AN) in the presence of a paraffin blowing agent. The effects of shell polymer properties including compositions, glass transition temperature (Tg), crosslinking degree, blowing agent type, and encapsulation ratio (Er) on the expansion properties of copolymer microspheres were investigated. Moreover, the diffusion properties of blowing agent in copolymer microspheres were studied. The results show that VDC-MMA-AN copolymer microspheres exhibited excellent expansion properties, and the volume expansion ratio (Ev) and the apparent density were decreased over 40 times, but it was difficult to expand for the VDC-MMA copolymer microspheres. In addition, the moderately crosslinked inside of the polymer shell enhanced the Ev more than 30 and the stable expansion temperature range (Tr) was about 30 °C by adding 0.2–0.4 wt% of divinyl benzene. The Tg of the shell polymer must be higher than the boiling point of the blowing agent as a prerequisite; the lower the boiling point of the blowing agent, the higher the internal gas pressure driven microsphere expansion, and the wider the Tr. By increasing the Er of blowing agent improved the Ev of the microspheres. The diffusion of pentane blowing agent in VDC-MMA-AN copolymer microspheres were divided into Fick diffusion and non-Fick diffusion. [ABSTRACT FROM AUTHOR]