A key challenge in guiding experiments toward materials with desired properties is to effectively navigate the vast search space comprising the chemistry and structure of allowed compounds. Here, it ...is shown how the use of machine learning coupled to optimization methods can accelerate the discovery of new Pb‐free BaTiO3 (BTO‐) based piezoelectrics with large electrostrains. By experimentally comparing several design strategies, it is shown that the approach balancing the trade‐off between exploration (using uncertainties) and exploitation (using only model predictions) gives the optimal criterion leading to the synthesis of the piezoelectric (Ba0.84Ca0.16)(Ti0.90Zr0.07Sn0.03)O3 with the largest electrostrain of 0.23% in the BTO family. Using Landau theory and insights from density functional theory, it is uncovered that the observed large electrostrain is due to the presence of Sn, which allows for the ease of switching of tetragonal domains under an electric field.
Accelerated materials discovery requires guiding experimentalists toward finding materials with targeted properties in as few measurements as possible. This work experimentally compares design strategies to discover new piezoelectrics with large strains at low electric fields in the lead‐free barium titanate family. The procedure by which new compositions can be obtained in an iterative feedback loop using machine learning is demonstrated.
The martensitic transformation serves as the basis for applications of shape memory alloys (SMAs). The ability to make rapid and accurate predictions of the transformation temperature of SMAs is ...therefore of much practical importance. In this study, we demonstrate that a statistical learning approach using three features or material descriptors related to the chemical bonding and atomic radii of the elements in the alloys, provides a means to predict transformation temperatures. Together with an adaptive design framework, we show that iteratively learning and improving the statistical model can accelerate the search for SMAs with targeted transformation temperatures. The possible mechanisms underlying the dependence of the transformation temperature on these features is discussed based on a Landau-type phenomenological model.
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Postpartum depressive disorder (PPD) is a unique subtype of major depressive disorder and a substantial contributor to maternal morbidity and mortality. However, the pathogenesis of PPD has still ...remained elusive, and it may associate with genetic and environmental factors. Gut microbiota has already been proved to be associated with depression; however, a limited number of studies have concentrated on PPD. The present study aimed to explore the potential correlations between gut microbiota and PPD. In this study, 57 participants were enrolled, in which fecal samples of 28 patients with PPD and 16 healthy controls (HCs) were collected and then analyzed by high-throughput sequencing of the 16S ribosomal RNA (rRNA) gene. The results showed that diversity and composition of gut microbial communities were partly different between PPD patients and HCs. The relative abundance of
phyla was lower in PPD patients. The levels of several predominant genera were significantly different between PPD patients and HCs. More importantly, the PPD patients experienced reduced levels of
, and
, as well as increased levels of
family. In addition, a correlation was observed between levels of
, and
and the severity of depressive symptoms. Various kinds of bacteria, such as
and
, were found to be associated with levels of sex hormones. This study indicated the correlation between gut microbiota and PPD, and gut microbiota-based biomarkers may be helpful for the diagnosis and treatment of PPD patients. However, further studies need to be conducted to clarify the cause-effect relationship between PPD patients and gut microbiota and to highlight the suitability of gut microbiome as a biomarker.
As coronavirus disease 2019 (COVID-19) pandemic poses a substantial global public health threat, traditional Chinese medicine (TCM) was used in 91.50% of the COVID-19 cases in China, showing ...encouraging results in improving symptom management and reducing the deterioration, mortality, and recurrence rates. A total of 166 modified herbal formulae consisting of 179 single herbal medicines were collected for treating COVID-19 in China. Glycyrrhizae Radix et Rhizome, Scutellariae Radix, and Armeniacae Semen Amarum are the most frequently utilized in clinics, most of which are antipyretic (47, 26.26%), expectorant and cough-suppressing (22, 12.29%), and dampness-resolving (21, 11.73%) from traditional descriptions. A total of 1212 chemical components containing β-sitosterol, stigmasterol, and quercetin were primarily selected. Additionally, using complex system entropy and unsupervised hierarchical clustering, 8 core herbal combinations and 10 new formulae emerged as potentially useful candidates for COVID-19. Finally, following scaffold analysis, self-organizing mapping (SOM) and cluster analysis, 12 clusters of molecules yielded 8 pharmacophore families of structures that were further screened as pharmacological targets in human metabolic pathways for inhibiting coronavirus. This article aims to make more easily accessible and share historical herbal knowledge used in contemporary treatments in a modern manner to assist researchers contain the global spread of COVID-19.
Herbal formulae were collected from 26 protocols for treating COVID-19. Using complex system entropy and unsupervised hierarchical clustering, 8 core combinations and 10 formulae emerged as potential candidates. Following scaffold analysis and self organizing mapping, 12 clusters of molecules yielded 8 pharmacophore structures screened as pharmacological targets for inhibiting corona virus. Display omitted
This paper proposes a hybrid dual path sub-sampling phase-locked loop (SSPLL), including a proportional path (P-path) and an integral path (I-path), with 0.8 V supply voltage. A differential ...master–slave sampling filter (MSSF), replacing the sub-sampling charge pump (SSCP), composed the P-path to avoid the degraded feature caused by the decreasing of the supply voltage. The I-path is built by a rail-to-rail SSCP to suppress the phase noise of the voltage-controlled oscillator (VCO) and avoid the trouble of locking at the non-zero phase offset (as in type-I PLL). The proposed design is implemented in a 40-nm CMOS process. The measured output frequency range is from 5.3 to 5.9 GHz with 196.5 fs root mean square (RMS) integrated jitter and −251.6 dB FoM.
In order to explore the origin and significance of music education reform and talent cultivation in the new era, this paper constructs a new music curriculum evaluation model based on SVM. Firstly, ...we explore the path of music education reform and the goal of music talent cultivation by taking the trend of Internet of everything as the origin of the proposed “high-quality courses” for music in universities. Then, we analyzed that the recognition accuracy of SVM is significantly better than most machine learning methods in solving high-dimensional small sample data, so we established a new music curriculum teaching evaluation model on this basis. The average score of each index of the new course teaching effect is 74, and the evaluation grade is better, obtained by establishing the evaluation system of the new music course of SVM. In the evaluation index, the CVI indexes were all kept in the range of 0.82 to 0.98, which was higher than the standard 0.78 of the CVI index, and the Kappa value of each evaluation index was higher than 0.86. The attendance rate in college teaching rose from 78% to 100%, the ability to master music knowledge rose from 67% to 93%, the ability to apply knowledge rose from 76% to 92%, and the average score on weekly tests rose from 86 to 96. Finally, it is concluded that the Internet-based music education reform approach can promote the development of music education careers and cultivate the important means of all-around talents.
The functional properties of shape memory alloys are strongly sensitive to the composition of alloys. In this study, the effect of Ti/Ni ratio and Hf/Zr ratio on the martensitic transformation ...behavior, shape memory effect and microscopic structures of two different quaternary TiNiHfZr alloys (TixHf15Zr5Ni80-x and Ti31.5HfyZr20-yNi48.5) have been investigated systematically. It is found that increasing Ti/Ni ratio of TixHf15Zr5Ni80-x alloys dramatically increases the martensitic transformation temperature and a maximum value (5%) of the recovered strain during shape recovery on heating is obtained for the alloy with x = 30. On the contrary, changing Hf/Zr ratio of Ti31.5HfyZr20-yNi48.5 alloys does not result in big change of martensitic transformation temperature or recovered strain. The evolution of macroscopic properties of TixHf15Zr5Ni80-x alloys with x can be understood by considering the balanced effect between the Ni content change of the matrix, and the volume fraction of Ti2Ni-like precipitates, which are often brittle and not desired for SMAs. Our results suggest that the TixHf15Zr5Ni80-x (x > 30.5 at. %) alloys are promising shape memory alloys for high temperature applications above 250 °C.
Allergic diseases such as allergic rhinitis (AR), allergic asthma (AAS), atopic dermatitis (AD), food allergy (FA), and eczema are systemic diseases caused by an impaired immune system. Accompanied ...by high recurrence rates, the steadily rising incidence rates of these diseases are attracting increasing attention. The pathogenesis of allergic diseases is complex and involves many factors, including maternal-fetal environment, living environment, genetics, epigenetics, and the body's immune status. The pathogenesis of allergic diseases exhibits a marked heterogeneity, with phenotype and endotype defining visible features and associated molecular mechanisms, respectively. With the rapid development of immunology, molecular biology, and biotechnology, many new biological drugs have been designed for the treatment of allergic diseases, including anti-immunoglobulin E (IgE), anti-interleukin (IL)-5, and anti-thymic stromal lymphopoietin (TSLP)/IL-4, to control symptoms. For doctors and scientists, it is becoming more and more important to understand the influencing factors, pathogenesis, and treatment progress of allergic diseases. This review aimed to assess the epidemiology, pathogenesis, and therapeutic interventions of allergic diseases, including AR, AAS, AD, and FA. We hope to help doctors and scientists understand allergic diseases systematically.
We report the existence of strain glass in Ti
50Ni
50−
x
Fe
x
, beyond a critical Fe doping level
x
>
x
c(5
<
x
c
<
6). The strain glass state is confirmed by the appearance of a frequency-dependent ...anomaly in the AC mechanical modulus/loss at a freezing temperature
T
0 and by the breaking of ergodicity shown in a zero-field-cooling/field-cooling experiment. Based on the experimental results, a phase diagram is established in which both the normal martensitic transformations (for
x
<
x
c) and the strain glass transition (for
x
>
x
c) are indicated. The new phase diagram allows for explanations of two long-standing puzzles in Ti
50Ni
50−
x
Fe
x
and Ti–Ni alloys: (i) the origin of nano-domains present prior to the martensitic transformation (for
x
<
x
c) and (ii) the negative temperature dependence of electrical resistivity in abnormal non-transforming compositions (for
x
>
x
c).
Toxic leadership is increasingly becoming common in the nursing field, but the measurement tools are lacking. Therefore, this study aimed to translate the toxic leadership behaviors of nurse managers ...(ToxBH-NM) scale into Chinese and test its psychometric properties among Chinese nurses.
The data for this study were obtained from a cross-sectional survey of 1,195 nurses. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to examine the structural validity of the ToxBH-NM. The following psychometric properties of the scale were assessed: content validity, criterion validity, internal consistency reliability, and test-retest reliability.
The Chinese version of the ToxBH-NM (C-ToxBH-NM) scale had two dimensions and 30 items. The correlation coefficients between the scores of each item and the total scores were 0762-0.922 (
< 0.001), and the range of the CR determination values of all the items were 8.610-18.998, with statistical significance (
< 0.001). The total content validity index (CVI) was 0.996, the average CVI was 0.996, and the item-level CVI was 0.875-1.000. Two common factors were identified in the EFA, and 81.074% of the variation was explained cumulatively. The CFA showed that all the fitting indexes reached the standard, and the model fit degree was good. When the Chinese version of the Destructive Leadership Scale was used as calibration, the correlation coefficient was 0.378 (
< 0.001). The Cronbach's alpha coefficients of the overall scale were 0.989 and of the two dimensions were 0.969 and 0.987, respectively, with a split-half reliability of 0.966 and test-retest reliability of 0.978.
The research results show that the C-ToxBH-NM scale has good reliability and validity and can be used to evaluate the severity of toxic leadership behavior among nursing managers.
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