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A new class of locally unital and locally finite dimensional algebras $A$ over an arbitrary algebraically closed field is discovered. Each of them admits an upper finite weakly triangular decomposition, a generalization of an upper finite triangular decomposition. Any locally unital algebra which admits an upper finite Cartan decomposition is Morita equivalent to some special locally unital algebra $A$ which admits an upper finite weakly triangular decomposition. It is established that the category $A$-lfdmod of locally finite dimensional left $A$-modules is an upper finite fully stratified category in the sense of Brundan-Stroppel. Moreover, $A$ is semisimple if and only if its centralizer subalgebras associated to certain idempotent elements are semisimple. Furthermore, certain endofunctors are defined and give categorical actions of some Lie algebras on the subcategory of $A$-lfdmod consisting of all objects which have a finite standard filtration. In the case $A$ is the locally unital algebra associated to one of cyclotomic oriented Brauer categories, cyclotomic Brauer categories and cyclotomic Kauffman categories, $A$ admits an upper finite weakly triangular decomposition. This leads to categorifications of representations of the classical limits of coideal algebras, which come from all integrable highest weight modules of $\mathfrak {sl}_\infty$ or $\hat {\mathfrak{sl}}_e$. Finally, we study representations of $A$ associated to either cyclotomic Brauer categories or cyclotomic Kauffman categories in details, including explicit criteria on the semisimplicity of $A$ over an arbitrary field, and on $A$-lfdmod being upper finite highest weight category in the sense of Brundan-Stroppel, and on Morita equivalence between $A$ and direct sum of infinitely many (degenerate) cyclotomic Hecke algebras., 33pages

BackgroundThe occupational health of university staff bears great social and economic value for which health utility is an indivisible aspect. Utility is also the primary data for the cost-utility analysis of occupational health programs. Health utility and occupational diseases have not been reported for the university staff in China. In the light of “Healthy China,” we conducted this study aiming to (1) estimate the health utility of university staff to inform cost-utility analysis and (2) screen and identify potential occupational diseases for this occupation and examine their impacts on health.MethodsAn occupational health survey was conducted in a sample of working-age university staff. Participants were interviewed face-to-face using the WHO Health and Work Performance Questionnaire and the European Quality of Life 5 Dimensions (EQ-5D) instrument to measure health conditions and health utility, respectively. The univariate analysis included the t-test, chi-square test, and correlation techniques. Multivariate generalized linear models were applied to evaluate the significance of each health condition when controlling for other factors.ResultsThe sample (n = 154) had a mean age of 40.65 years and consisted of slightly more women (51.30%). Participants attained a mean (standard deviation) health utility of 0.945 (0.073). The most affected domain was anxiety/depression with 62 (40.26%) participants reporting problems, followed by pain/discomfort which captured 60 (37.66%) staff with problems. Thus, pain and psychologically related conditions were prevalent. Multivariate models identified two conditions that can significantly reduce the health utility. The psychological/emotional conditions were associated with a utility loss of −0.067 (95%CI: −0.089, −0.045). The pain in body parts other than the head, neck, and back reduced the utility by −0.034 (95%CI: −0.055, −0.014).ConclusionWorking-age staff in Chinese universities may have a lower health utility than the general population. Psychological conditions and musculoskeletal pain appear like occupational diseases. With the health utility data available, economic evaluation of cost-utility should follow up to facilitate the implementation of cost-effective programs.

Electronic interactions can radically enhance the performance of supported metal catalysts and are critical for fundamentally understanding the nature of catalysts. However, at the microscopic level, the details of such interactions tuning the electronic properties of the sites on the metal particle's surface and metal-support interface remain obscure. Herein, we found polarized electronic metal-support interaction (pEMSI) in oxide-supported Pd nanoparticles (NPs) describing the enhanced accumulation of electrons at the surface of NPs (superficial Pd δ-) with positive Pd atoms distributed on the interface (interfacial Pd δ+). More superficial Pd δ- species mean stronger pEMSI resulting from the synergistic effect of moderate Pd-oxide interaction, high structural fluxionality and electron transport activity of Pd NPs. The surface Pd δ- species are responsible for improved catalytic performance for H2 evolution from metal hydrides and formates. These extensive insights into the nature of supported-metal NPs may open new avenues for regulating a metal particle's electronic structure precisely and exploiting high-performance catalysts.

Upgrading liquid electrolytes with all-solid-state electrolytes (ASEs) or quasi-solid-state electrolytes (QSEs) for solid-state batteries (SBs) have emerged not only to address the intrinsic disadvantages of traditional liquid lithium ion batteries, but also to offer more possibilities for the development of new battery chemistries. In this work, a novel rambutan-like yolk–shell-structured porous γ-AlOOH microsphere with a large specific surface area of 262.92 m2 g−1 was firstly obtained by a simple hydrothermal synthesis route, which was then utilized as a robust framework to assemble QSE via encapsulating abundant liquid electrolyte (LE). The obtained γ-AlOOH-QSE exhibits a high ionic conductivity of 4.0 × 10−3 S cm−1, a large lithium ion transference number (tLi+) of 0.76, as well as a wide electrochemical window of 4.72 V vs. Li/Li+. Moreover, the assembled cell of LiFePO4/γ-AlOOH-QSE/Li could maintain a high specific capacity of 144.4 mA h g−1 even after 120 cycles with almost negligible capacity decay, which could be mainly attributed to the excellent interfacial compatibility, prominent performance in suppressing lithium dendrite growth upon cycling (rigid characteristic), as well as the high ionic conductivity of γ-AlOOH-QSE (intrinsic advantage). This work could not only expand the applications of QSE with cost-effective aluminum-based oxides with facile fabrication strategy, but also will shed light on the construction of SEs with more integrated QSEs and ASEs in the field of advanced energy storage.

Given the unprecedented size of ultraspectral sounder data, there is a special process of radiance thinning in assimilating this data to reduce the data volume with minimal loss of atmospheric information. Considering the potential correlation between the selected data by radiance thinning and the unselected data, a lossless compression method for ultraspectral sounder data is proposed based on key information extraction and spatial–spectral prediction. Sensitive channels are first selected by stepwise iteration based on information entropy to maintain critical atmospheric information, and then auxiliary channels are further selected based on information content and correlation constraints to facilitate prediction. All of the selected channels are spatially thinned to generate key information, which is then used to predict original ultaspectral sounder data by spatially bicubic interpolation and spectrally sparse reconstruction. The residual errors are processed by the least-squares linear prediction to further reduce data redundancy. Together with the key information, the final residual errors are then fed into a range coder after positive mapping and histogram packing. Experimental results with IASI-L1C data show that the proposed method achieves an average compression ratio of 2.68, which is 4.7% higher than that of the typical methods, including JPEG-LS, JPEG-2000, M-CALIC, CCSDS-122.0, CCDS-123.0, and HEVC.

Simple Summary Broiler sound signals can reflect their own health status, such as crowing when they are hungry, coughing when they are in pain or ill, purring when there are foreign bodies in their throat, and flapping wings when they are fighting with each other. Many studies have been carried out to improve animal welfare based on this. However, the reality is that in addition to the emotional sounds mentioned above, there still exists back noise in the broiler sound signal collected in the farm, such as the noise of people walking and ventilation equipment. Therefore, it is necessary to adopt effective signal filtering methods to filter out these noises, and further obtain high-quality broiler sound signals for animal welfare research. In this study, five of the most classic and effective signal filtering methods were used to filter the back noise in broiler sound signals, and different evaluation indicators from two angles were used for “scoring” the filtering effect of each method in order to select the outstanding performers. These studies have laid the foundation for the follow-up study of broiler health monitoring. Abstract Broiler sounds can provide feedback on their own body condition, to a certain extent. Aiming at the noise in the sound signals collected in broiler farms, research on evaluating the filtering methods for broiler sound signals from multiple perspectives is proposed, and the best performer can be obtained for broiler sound signal filtering. Multiple perspectives include the signal angle and the recognition angle, which are embodied in three indicators: signal-to-noise ratio (SNR), root mean square error (RMSE), and prediction accuracy. The signal filtering methods used in this study include Basic Spectral Subtraction, Improved Spectral Subtraction based on multi-taper spectrum estimation, Wiener filtering and Sparse Decomposition using both thirty atoms and fifty atoms. In analysis of the signal angle, Improved Spectral Subtraction based on multi-taper spectrum estimation achieved the highest average SNR of 5.5145 and achieved the smallest average RMSE of 0.0508. In analysis of the recognition angle, the kNN classifier and Random Forest classifier achieved the highest average prediction accuracy on the data set established from the sound signals filtered by Wiener filtering, which were 88.83% and 88.69%, respectively. These are significantly higher than those obtained by classifiers on data sets established from sound signals filtered by other methods. Further research shows that after removing the starting noise in the sound signal, Wiener filtering achieved the highest average SNR of 5.6108 and a new RMSE of 0.0551. Finally, in comprehensive analysis of both the signal angle and the recognition angle, this research determined that Wiener filtering is the best broiler sound signal filtering method. This research lays the foundation for follow-up research on extracting classification features from high-quality broiler sound signals to realize broiler health monitoring. At the same time, the research results can be popularized and applied to studies on the detection and processing of livestock and poultry sound signals, which has extremely important reference and practical value.

The distribution patterns of equivalent static seismic lateral forces used in current structural design codes are mostly derived from elastic vibration modes. Such force patterns may not be consistent with actual conditions when structures behave into the inelastic range or even into the collapse stage. In this study, a new design method for multi-story buildings that uses an optimum lateral force pattern is proposed based on the concept of uniform damage distribution at the collapse state of these buildings. To reduce the computational cost of statistical analyses for deriving the optimum lateral force pattern, the non-linear story behaviors are represented by a story shear-deformation model with tri-linear relationships. Systematic parametric analyses are performed to study the influences of various ground motion parameters (site condition, magnitude, distance to rupture, and near-fault effect) and structural parameters (number of stories, fundamental period, damping ratio, post-yielding stiffness, ductility, and degrading stiffness) on the optimum lateral force pattern. Formulas for the optimum lateral force pattern that are applicable for practical seismic designs are provided. The collapse resistant capacities of structures designed using the proposed and conventional methods are compared by fragility analyses. Results show that the proposed method increases the seismic collapse resistant capacity of structures under the same construction cost.

A fluorescent probe composed of BODIPY and 2,4-dinitrophenylhydrazine was designed for the detection of ClO−. The oxidizing reaction between probe and ClO− resulted in a distinct fluorescence enhancement together with a color variation from pink to orange. This probe showed excellent selectivity to ClO− among various ions including common reactive oxygen species and high sensitivity with a detection limit of 228 nM. A fast response (7 min) was observed, which made the probe a promising method in real-time detection. Furthermore, this probe was successfully applied to monitor ClO− in real-life water and living cells.

Due to the complex internal structure and uneven composition material of sealed electronic equipment, traditional acoustic emission source localization methods are unsuitable for the research of locating loose particles inside sealed electronic equipment. Aiming at this problem, the author analyzed the essence of locating loose particles from another angle, considered converting the loose particle localization problem into the multi-classification problem, and sought for solving. Based on the existing loose particle detection system, the multi-channel signal synchronous acquisition circuit was designed to synchronously collect loose particle signals. The two-stage dual-threshold pulse extraction algorithm and the multi-channel pulse-matching algorithm were designed to preprocess the collected loose particle signals. Multiple features with good localization performance were extracted and selected from the processed loose particle signals, and the localization data set was eventually established. The localization performances of different classification algorithms were analyzed and compared by performing them on the localization data set, respectively, then the parameters of better-performed Random Forest were optimized. Finally, the loose particle localization model based on parameter-optimized Random Forest was used to perform localization tests on the aerospace power supply. Test results show that the average localization accuracy is 84.08%, which is the highest localization accuracy achieved in aerospace engineering area of the world currently. It is an important supplement to the loose particle detection research and has important application value for improving the reliability of aerospace system. Theoretically, it can be applied to the research of collision signal localization with similar generation mechanism.

Hypochlorite serves as a powerful antimicrobial agent in human immune system, the detection of which is of great significance. Herein a novel fluorescent probe based on BODIPY dye and diaminomaleonitrile has been synthesized and characterized to sense hypochlorite. The fluorescence of the system is dramatically enhanced by ClO− due to the removal of C=N isomerization effect in physiological pH condition. The complete reaction only needs a few seconds, which enables the probe to facilitate real-time detection. This probe also has satisfactory selectivity for ClO− even in the presence of other interferential ions and shows high sensitivity with a detection limit of 19.8 nM. Furthermore, Probe 1 has been successfully applied to detect ClO− in real water samples.

High voltage LiNi0.5Mn1.5O4 cathodes are of prime importance for the development of next generation lithium-ion batteries (LIBs) with high energy density. LiNi0.5Mn1.5O4, however, always was attacked by the generated HF from the electrolyte decomposition during cycling, leading to instable surface structure and poor Li+ diffusion kinetic property. In this regard, YF3 with good thermal stability and excellent structural stability in the HF containing electrolyte, is chosen as coating layer to modify the surface of LiNi0.5Mn1.5O4. Ex-situ electrochemical impedance spectroscopy study and inductively coupled plasma analysis indicate that YF3 coating layer on the surface of LiNi0.5Mn1.5O4 could act as protect medium to effectively suppress side reactions between the LiNi0.5Mn1.5O4 surface and electrolyte, and thus enhance its structural stability and kinetics properties during repeated electrochemical reactions. As a result, LiNi0.5Mn1.5O4 after YF3 modification shows the improved capacity retention of 84% after 100 cycles at 0.1C, and 78 mAh g−1 could be obtained at 2C, much higher than those of the pristine LiNi0.5Mn1.5O4 cathode (78%, 24 mAh g−1). Furthermore, differential scanning calorimetry result confirms the enhanced thermal stability of LiNi0.5Mn1.5O4 after YF3 coating. These findings open up chance to prepare high performance LiNi0.5Mn1.5O4 cathode and promote development of LIBs with high energy density.

Organic-inorganic composite solid state electrolytes (SSEs), as one of the most attractive candidates for next generation SSEs, combines the both advantages of flexibility (from organic polymer) and structure rigidity (from robust inorganic constituent). In this work, a high performance three-dimensional (3D) crosslinked electrolyte with polymer poly(vinylidene fluoride) (PVDF) and polyethylene oxide (PEO) matrices is further modified by dispersing submicron fast ion conductor Li1.4Al0.4Ti1.6(PO4)3 (LATP). The optimal 3D composite SSE PVDF@10PEO-5LATP-5LiPF6 (PPLL) shows high ionic conductivities of 5.24 × 10−4 S cm−1 at 25 °C and above 10−3 S cm−1 at 50 °C. Galvanostatic cycling test demonstrates that PPLL contributes to electrochemical performances, with high capacity retention of 93.95% after 500 cycles for LiFePO4 cathode. Further investigations indicate its more benefits including excellent flexibility and superior safety. Intensive explorations imply that the interaction between dual-matrix degrades the respective crystallization through generating weak bonding, and the recombination with LATP further enhances ionic conductivity as well as structural stability of composite electrolyte via strengthening interface reaction, and reducing the organic crystallinity. This composite SSE with high conductivity and stability may be applied in next generation energy storage devices, particularly in all-solid-state secondary batteries.

In this paper, a notion of affine walled Brauer-Clifford superalgebras $BC_{r, t}^{\rm aff} $ is introduced over an arbitrary integral domain $R$ containing $2^{-1}$. These superalgebras can be considered as affinization of walled Brauer superalgebras in \cite{JK}. By constructing infinite many homomorphisms from $BC_{r, t}^{\rm aff}$ to a class of level two walled Brauer-Clifford superagebras over $\mathbb C$, we prove that $BC_{r, t}^{\rm aff} $ is free over $R$ with infinite rank. We explain that any finite dimensional irreducible $BC_{r, t}^{\rm aff} $-module over an algebraically closed field $F$ of characteristic not $2$ factors through a cyclotomic quotient of $BC_{r, t}^{\rm aff} $, called a cyclotomic (or level $k$) walled Brauer-Clifford superalgebra $ BC_{k, r, t}$. Using a previous method on cyclotomic walled Brauer algebras in \cite{RSu1}, we prove that $BC_{k, r, t}$ is free over $R$ with super rank $(k^{r+t}2^{r+t-1} (r+t)!, k^{r+t}2^{r+t-1} (r+t)!)$ if and only if it is admissible in the sense of Definition~6.4. Finally, we prove that the degenerate affine (resp., cyclotomic) walled Brauer-Clifford superalgebras defined by Comes-Kujawa in \cite{CK} are isomorphic to our affine (resp., cyclotomic) walled Brauer-Clifford superalgebras., Comment: 33 pages