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Current range-gated imaging methods based on triangular or trapezoidal models face significant limitations in terms of the accuracy and precision of three-dimensional (3D) reconstruction. Here, we establish a range-gated 3D super-resolution image reconstruction method based on a Gaussian-range-intensity model. A denoised optimization method for image preprocessing is established to improve the distance accuracy of the reconstruction. The experimental results show that the model can reduce the error of target distance by 64% and possess the reconstruction of multiple kinds of targets with a distance resolution of 1.5 cm and lower noise, realizing better reconstruction results compared with the existing range-gated 3D imaging techniques.
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Imaging through the scattering medium, such as fog, is important for military and civilian applications. However, the fog concentration restricts the current defogging methods; the image will be seriously degraded in dense fog scenes. Here, an imaging technique by developing joint active polarization defogging and denoising optimization methods based on range-gated detection is proposed for the target in fog conditions. The range-gated imaging method shields the scattering light from outside the selected region to improve the signal intensity. The properties of signal light, backscattering light, and forward scattering light in the range-gated imaging way are analyzed experimentally and theoretically. Thus the elimination method of backscattering light is developed in terms of polarization differences in the degree of polarization and angle of polarization, and the block-matching with 3D transform-domain collaborative filtering (BM3D) algorithm is developed to remove the effect of the forward scattering light on the image. By adopting the proposed defogging method, the clear imaging of the target under fog with an optical thickness of up to 5 is realized, and the target contour and detail information are successfully recovered. Compared with the complete failure of the current defogging method, this method can recover targets with high contrast and signal-to-noise ratio in dense fog scenes, which exhibits widespread application potential for target detection and recognition in severe weather and turbid underwater environment.
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Dicaffeoylquinic acids (diCQAs) are found in a variety of edible and medicinal plants with various biological activities. An important issue is the low stability of diCQAs during extraction and food processing, resulting in the degradation and transformation. This work used 3,5-diCQA as a representative to study the influence of different parameters in ultrasonic treatment on the stability of diCQAs, including solvent, temperature, treatment time, ultrasonic power, duty cycle, and probe immersion depth. The generation of free radicals and its influence were investigated during the treatment. The stability of three diCQAs (3,5-diCQA, 4,5-diCQA and 3,4-diCQA) under the certain ultrasonic condition at different pH conditions was evaluated and found to decrease with the increase of pH, further weakened by ultrasonic treatment. Ultrasound was found to accelerate the degradation and isomerization of diCQAs. Different diCQAs showed different pattern of degradation and isomerization. The stability of diCQAs could be improved by adding epigallocatechin gallate and vitamin C.
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Steam explosion (SE) pretreatment is an efficient technique to promote the fiber degradation and disrupt materials' cell wall. In this study, the effect of SE pretreatment on the changes in phenolic profile, and the in vitro digestion property of a Chinese indigenous herb "Hangbaiju" (HBJ) powder with various sieve fractions (150-, 180-, 250-, 425-, and 850-µm sieves) were studied. After SE pretreatment, the morphological structure, color attributes, and composition of phenolic compounds were altered significantly (p < .05). The composition and content of phenolic compounds were strongly correlated with particle sizes. The higher extraction yield of phenolic compounds was reached in the intermediate sieve fraction (ca. 250-µm sieves). During in vitro digestion, the changes in phenolic compounds were significant due to the transition from an acidic to the alkaline environment (p < .05). Based on the multivariate statistical analysis, apigenin-7-O-glucoside, luteolin-7-O-glucoside, and linarin, were viewed as the characteristic compounds among various samples. The results highlighted that the phytochemical properties mainly including the composition of phenolic compounds, and in vitro digestion properties of HBJ powder with intermediate sieve fraction could be improved after SE pretreatment.
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BACKGROUND: The relationship between workplace incivility and psychological distress among nurses has been well-documented in the nursing literature. Management practices to reduce the negative impact are less clear. This study aimed to examine perceived servant leadership as a moderator between workplace incivility and psychological distress among nurses in Chinese hospitals. METHODS: This study used a cross-sectional design and was conducted between September and October 2020. We recruited 1,604 nurses from 13 Chinese hospitals across different regions in China ranging from 18 to 55 years in age (M = 28.48 years, SD = 6.53 years). Multiple linear regression was used to analyze the data. FINDINGS: The results showed that workplace incivility (ß = 0.40, p < .001) and perceived servant leadership (ß = -0.13, p < .001), as well as their interaction (ß = -0.11, p = .002), predicted nurses' psychological distress. Perceived servant leadership moderates the relationship between workplace incivility and psychological distress. CONCLUSIONS/APPLICATION TO PRACTICE: Servant leaders can create an ethical work climate, display empathy and compassion, and facilitate resilience. Our findings can assist hospital management with support from occupational health providers to recruit, train, and assess nursing supervisors. Also, occupational health providers in collaboration with nursing administration can monitor incivility, psychological distress, servant leadership levels, and impact.
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Incivility , Nursing Staff, Hospital , Psychological Distress , Adult , Cross-Sectional Studies , Humans , Leadership , Nursing Staff, Hospital/psychology , Surveys and Questionnaires , Workplace/psychologyABSTRACT
5-O-Caffeoylquinic acid (5-CQA), also known as chlorogenic acid, exhibits various biological activities. Hence the interest in its property change during processing and extraction has increased. The present work studied the influence of ultrasound on the stability of 5-CQA at different pH (pH 4.69, 7.09, 7.69 and 9.22) in water and 50% methanol-water system. Different parameters including solvent, ultrasonic power, time, temperature, duty cycle, and liquid height were investigated during the treatment. Results indicate that ultrasound accelerated the degradation of 5-CQA. Based on Weibull model, the degradation kinetics were described. The rate constant (k) of the degradation increased with the increasing pH, demonstrating the alkali sensitivity of 5-CQA. The isomerization of 5-CQA to 3- and 4-O-caffeoylquinic acid was found at neutral and alkaline conditions, which was further boosted by ultrasound. The stability of 5-CQA was improved by adding epigallocatechin gallate (EGCG) and vitamin C (VC) respectively.
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Caffeoylquinic acids are existed in many plant species with various biological and pharmacological activities. 3-O-caffeoylquinic acid and 4-O-caffeoylquinic acid are two isomers of caffeoylquinic acids, which may be degraded and transformed to their isomers in processing. The present paper found that the stability of 3- and 4-O-caffeoylquinic acid had decreased with the increasing solution alkalinity. 3-O-caffeoylquinic acid was more stable than 4-O-caffeoylquinic acid at the same condition. During degradation, 3- and 4-O-caffeoylquinic acid were partially converted to their isomers. Additionally, ultrasonic effects on the degradation and isomerization of 3- and 4-O-caffeoylquinic acid at different pH were studied. Ultrasound facilitated the degradation and isomerization of these compounds. The degradation kinetics were described by the Weibull equation. The protective effect of ascorbic acid and epigallocatechin gallate were also explored. Ascorbic acid and epigallocatechin gallate could alleviate the degradation of 3- and 4-O-caffeoylquinic acid under certain conditions.
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PURPOSE: Nurses' behaviors are largely influenced by their managers' leadership style. The relationships between ethical leadership, trust, psychological well-being, and organizational citizenship behaviors have rarely been investigated in nursing studies. The current study attempted to examine the relationships between perceived ethical leadership, trust, psychological health, and nurses' organizational citizenship behaviors towards their patients in the context of Chinese hospitals. METHODS: This research adopted a cross-sectional research design. Participants were 495 nurses solicited from six hospitals in China. Hayes's PROCESS and SPSS 22 were employed to analyze the data. RESULTS: This study demonstrated ethical leadership perceived by nurses is positively associated with trust in management and psychological well-being. Trust in management is also positively associated with nurses' organizational citizenship behaviors. The indirect effects of perceived ethical leadership on organizational citizenship behaviors through trust in management and psychological well-being were statically significant. CONCLUSION: This study adds value to the literature by revealing ethical leadership boosts nurses' trust in leadership and their psychological well-being, resulting in more organizational citizenship behaviors towards patients in the context of the Chinese hospitals. It is suggested that the hospital management creates an environment in which all members are treated fairly to boost nurses' psychological health and improve their service quality toward patients' satisfaction.
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Many students suffer from academic stress and uncivil behaviors at colleges and there is a need to identify to what extent these negative phenomena might impact students' mental health. The main purpose of this study is to examine the relationships between incivility, academic stress, and psychological health, as well as investigate the moderating role of gratitude. The study design of this research is cross-sectional. The final sample consisted of 895 university students in China; The Statistical Package for the Social Sciences (SPSS) version 22 was utilized to conduct statistical analysis. Sample t-tests were used to examine whether there were gender differences in terms of four continuous variables: incivility, stress, gratitude, and psychological wellbeing. We also used multiple hierarchical linear regression analysis to test the relationships between the aforementioned four variables and the moderating effect of gratitude. The results of our study indicate that academic stress and incivility are positively associated with psychological distress, and gratitude moderates the relationship between incivility and psychological distress. However, no significant moderating effect of gratitude was found in the relationship between academic stress and psychological distress.
Subject(s)
Incivility , Mental Health , Students , China , Cross-Sectional Studies , Humans , Stress, Psychological , Students/psychology , Surveys and Questionnaires , UniversitiesABSTRACT
AIMS: To examine the relationships between perceived ethical leadership, perceived interactional justice climate, and patient-oriented organizational citizenship behaviour. DESIGN: A cross-sectional non-experimental design was employed. METHODS: The convenience sampling was adopted. Data were collected in July and August 2018. A total of 738 nurses were recruited from eight Chinese hospitals. The survey included instrument scales of ethical leadership, interactional justice climate, and patient-oriented organizational citizenship behaviour. SPSS version 22 was used to compute means, standard deviations, and intercorrelations. The partial least squares structural equation modelling was chosen to estimate the path coefficients of the relationships. RESULTS: Relationships among perceived ethical leadership, perceived interactional justice climate, and organizational citizenship behaviours were statistically significant. Perceived interactional justice climate mediated the relationship between perceived ethical leadership and nurses' organizational citizenship behaviours. CONCLUSIONS: Ethical leadership is related to interactional justice climate, which, in turn, increases nurses' organizational citizenship behaviour. Nurse leaders are encouraged to exhibit ethical behaviours and to create justice climate. Ethical leadership scale can be used to select, train, and evaluate the nurse supervisors and managers. IMPACT: Hospital administrators are encouraged to recruit and promote those with both moral compass and leadership potential to nursing leadership positions. Nursing managers should create a justice climate in their hospitals. Hospital administrators could use ethical leadership scale to develop ethical leadership training programmes.
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Nurse Administrators , Nursing Staff, Hospital , Attitude of Health Personnel , Cross-Sectional Studies , Humans , Job Satisfaction , Leadership , Morals , Organizational Culture , Surveys and QuestionnairesABSTRACT
This study investigated the phenolic compounds of 15 Chrysanthemum morifolium Ramat cv. 'Hangbaiju', including 6 'Duoju' and 9 'Taiju', using high performance liquid chromatography (HPLC). The antioxidant activities of these 'Hangbaiju' were estimated by DPPH, ABTS and FRAP assays. Results show that a total of 14 phenolic compounds were detected in these flowers, including 3 mono-caffeoylquinic acids, 3 di-caffeoylquinic acids, 1 phenolic acid and 7 flavonoids. 'Duoju' and 'Taiju' possess different concentrations of phenolic compounds, and 'Taiju' exhibits higher caffeoylquinic acids and stronger antioxidant activities than 'Duoju'. Caffeoylquinic acids show a strong correlation with the antioxidant activities of the samples. Principal component analysis (PCA) reveals an obvious separation between 'Duoju' and 'Taiju', using phenolic compounds as variables. Apigenin-7-O-glucoside, 3,5-di-O-caffeoylquinic acid, luteolin and acacetin were found to be the key phenolic compounds to differentiate 'Duoju' from 'Taiju'.
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Schoolteachers worldwide are facing stressful work conditions with heavy responsibilities. Stress may contribute to psychological disorders and physical health issues. The purposes of this study were (1) to investigate whether both challenge and hindrance stressors are positively associated with emotional exhaustion among Chinese schoolteachers and (2) to examine whether perceived servant leadership moderates the effects of challenge and hindrance stressors on emotional exhaustion. This study was cross-sectional in nature. A sample of 2636 schoolteachers was elicited from schools in South China. Research data were collected in the fall semester of 2019 via WeChat®. Descriptive statistics and inter-correlations were conducted using SPSS 21. Confirmatory factor analysis was applied to test measurement models to determine convergent and discriminant validities using Mplus 7.4. Hierarchical multiple regression was performed to test proposed hypotheses using SPSS 21. The study results demonstrated that both challenge and hindrance stressors were positively related to emotional exhaustion among schoolteachers in Chinese schools. It was also indicated that, while perceived servant leadership buffers the relationship between challenge stressor and emotional exhaustion, it enhances the relationship between hindrance stressor and emotional exhaustion. Implications and limitations are also provided.
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Burnout, Professional/psychology , Emotions , Leadership , Adult , China , Cross-Sectional Studies , Factor Analysis, Statistical , Female , Humans , Male , Middle Aged , Multivariate AnalysisABSTRACT
The residual level and dissipation rate of triazophos in wheat crops and the soil in which they were grown were determined by gas chromatography (GC). Maximum final residues of triazophos in wheat grain, stems and leaves, and soil were 1.865, 44.506, and 0.973 mg/kg, respectively. The mean half-life of triazophos in wheat plants (grain, stems, and leaves) was 5.22 days with a dissipation rate of 90% over 14 days. The half-life in soil was 7.93 days with a dissipation rate of 90% over 21 days. Dissipation rates in two geographically separated experimental fields differed, suggesting that this was affected by local soil characteristics and climate. Although residual levels of triazophos in wheat plants may pose risks to the health of humans and other animals, comparatively low residues in soil suggest that this pesticide may be otherwise environmentally safe.