Role stress, occupational burnout and depression among emergency nurses: A cross-sectional study.

BACKGROUND: Emergency nurses are a professional group at a high risk of burnout and depression. This may influence their mental state and physical health. AIMS: The aim of the study was to explore the relationship between role stress, occupational burnout and depression among emergency nurses. METHODS: A cross-sectional study was carried out among 295 emergency nurses from eight tertiary hospitals in western China. The Role Stress Scale, the Maslach Burnout Inventory-Human Services Survey and the Center for Epidemiologic Studies Depression Scale were employed. Descriptive statistics, independent sample t-tests, one-way analysis of variance, Pearson's correlation analysis and regression analysis were performed. RESULTS: Of the study participants, 54.6% were found to have depressive symptoms and 48.1% had severe occupational burnout. Positive correlations were observed between the scores of role stress and burnout and depression. Approximately 37.1% of the variation in depression was explained by the components of occupational burnout. CONCLUSIONS: Emergency nurses experience high levels of role stress, occupational burnout and depression. Preventive approaches to role stress, burnout and depression are needed to improve their psychological condition and quality of work life.

[L-carnitine-astaxanthin compound nutrients for the treatment of idiopathic oligospermia and asthenozoospermia: A multicenter clinical observation].

OBJECTIVE: To investigate the clinical effects of the L-carnitine-astaxanthin compound nutrients Menglankang (MLK) on idiopathic oligospermia (OS) and asthenospermia (AS). METHODS: This study included 73 cases of OS and 220 cases of AS treated with MLK once a bag, bid, for 3 successive months. Before and at 1, 2 and 3 months after treatment, we obtained and analyzed the semen parameters and sperm DNA fragmentation index (DFI) of the patients. RESULTS: Compared with the baseline, the OS patients showed remarkable increases after 1 and 2 months of treatment in the semen volume (ï¼»3.07 ± 1.47ï¼½ vs ï¼»3.26 ± 1.26ï¼½ and ï¼»3.30 ± 1.28ï¼½ ml), sperm concentration (ï¼»10.96 ± 6.09ï¼½ vs ï¼»16.74 ± 11.15ï¼½ and ï¼»17.56 ± 9.92ï¼½ ×106/ml, P < 0.05), total sperm count (ï¼»29.78 ± 17.48ï¼½ vs ï¼»52.98 ± 32.07ï¼½ and ï¼»57.67 ± 36.98ï¼½ ×106, P < 0.05) and the percentages of progressively motile sperm (PMS) (ï¼»39.8 ± 11.66ï¼½% vs ï¼»45.3 ± 14.03ï¼½% and ï¼»46.42 ± 10.69ï¼½%, P < 0.05) and morphologically normal sperm (MNS) (ï¼»1.71 ± 1.07ï¼½% vs ï¼»1.79 ± 0.91ï¼½% and ï¼»1.84 ± 0.96ï¼½%), and so did the AS patients in PMS (ï¼»19.23 ± 8.32ï¼½% vs ï¼»25.46 ± 13.86ï¼½% and ï¼»27.33 ± 12.88ï¼½%, P < 0.05). After 3 months of medication, the OS patients exhibited even more significant increases in the semen volume (ï¼»3.63 ± 1.39ï¼½ ml) (P < 0.05), sperm concentration (ï¼»20.56 ± 14.7ï¼½ ×106/ml) (P < 0.05), total sperm count (ï¼»66.35 ± 55.91ï¼½ ×106) (P < 0.05), PMS (ï¼»49.24 ± 13.45ï¼½%) (P < 0.05) and MNS (ï¼»2.59 ± 0.93ï¼½%) (P < 0.05), and so did the AS patients in the semen volume (ï¼»3.27 ± 1.42ï¼½ vs ï¼»3.85 ± 1.59ï¼½ ml, P < 0.05), PMS (ï¼»29.11 ± 13.58ï¼½%) (P < 0.05) and NMS (ï¼»2.01 ± 1.14ï¼½% vs ï¼»2.57 ± 1.15ï¼½%, P < 0.05). In comparison with the baseline, the sperm DFI was not significantly improved at 1 month after treatment, but remarkably decreased at 2 and 3 months in the OS patients (ï¼»25.87 ± 13.76ï¼½% vs ï¼»18.66 ± 10.83ï¼½% and ï¼»16.48 ± 11.46ï¼½%, P < 0.05) and the AS patients as well (ï¼»26.40 ± 12.28ï¼½% vs ï¼»19.35 ± 11.54ï¼½% and ï¼»15.32 ± 10.89ï¼½%, P < 0.05). CONCLUSIONS: The L-carnitine-astaxanthin compound nutrients Menglankang can significantly improve the semen quality of the patients with idiopathic oligospermia or asthenospermia.

[Correlation of sperm DNA fragmentation index with age and semen parameters and its influence on the outcomes of IVF-ET].

OBJECTIVE: To explore the correlation of the sperm DNA fragmentation index (DFI) with age and other semen parameters in infertile men and its influence on the outcomes of in vitro fertilization and embryo transplantation (IVF-ET). METHODS: Semen samples were obtained from 6 162 infertile males in our hospital between July 2017 and December 2018. Sperm concentration, the percentages of progressively motile sperm (PMS) and morphologically normal sperm (MNS) and sperm DFI were determined by computer-assisted semen analysis, modified Papanicolaou staining and sperm chromatin structure assay, respectively. According to the sperm DFI, the samples were divided into three groups: DFI≤15%, 15%30%. Comparisons were made among different groups in the rates of fertilization, embryo cleavage, embryo formation and pregnancy. RESULTS: Spearman correlation analysis showed that DFI was correlated positively with age (r = 0.508, P < 0.05), but negatively with sperm concentration (r = －0.155, P < 0.05) and the percentages of PMS (r = －0.111, P < 0.05) and MNS (r = －0.315, P < 0.05). With sperm DFI >20%, the clinical pregnancy rate of IVF-ET was significantly reduced, while with sperm DFI >30%, the rate of available embryos markedly decreased and that of biochemical pregnancy remarkably increased. No correlation was found between sperm DFI and the rates of fertilization, embryo cleavage and high-quality embryos in IVF-ET. CONCLUSIONS: In infertile males, sperm DFI is correlated positively with age but negatively with sperm concentration and the percentages of PMS and MNS, and it significantly affects the outcomes of IVF-ET.

[Monitor of Cyanobacteria Bloom in Lake Taihu from 2001 to 2013 Based on MODIS Temporal Spectral Data].

Algal bloom highly impacts the ecological balance of inland lakes. Remote sensing provides real-time and large-scale observations, which plays an increasingly significant role in the monitoring of algal bloom. Various Vegetation Indices (VIs) derived from satellite images have been used to monitor algae. With threshold segmentation of VI, the area of algal bloom can be extracted from images. However, the result of threshold segmentation only reflects the condition of algae when images were generated. Compared to separated VI data obtained at a particular moment of time, temporal spectral VI data contains phonological information of algae, which may be used to evaluate algal bloom more accurately and comprehensively. This study chose MODIS NDVI data of the Lake Taihu from 2001 to 2013, and constructed temporal spectral data for each year. Then, we determined the feature temporal spectra of severe cyanobacteria bloom, moderate cyanobacteria bloom, slight cyanobacteria bloom and aquatic plants, and separated these four kinds of objects using SVM (Support Vector Machine) algorithm, getting the spatial distribution and area of them. In order to compare the results of our method with traditional threshold segmentation method, we chose 8 separated NDVI images from the temporal spectral data of 2007. With the threshold 0.2 and 0.4, cyanobacteria bloom was classified into three degrees: severe cyanobacteria bloom, moderate cyanobacteria bloom, and slight cyanobacteria bloom. By comparison, it showed that our method reflected cyanobacteria bloom more comprehensively, and could distinguish cyanobacteria and aquatic plants using the phonological information provided by NDVI temporal spectra. This study provides important information for monitoring the algal bloom trends and degrees of inland lakes, and temporal spectral method may be used in the forecast of algal bloom in the future.

[Research on the model of spectral unmixing for minerals based on derivative of ratio spectroscopy].

The precise analysis of mineral abundance is a key difficulty in hyperspectral remote sensing research. In the present paper, based on linear spectral mixture model, the derivative of ratio spectroscopy (DRS) was introduced for spectral unmixing of visible to short-wave infrared (Vis-SWIR; 0.4 - 2.5 microm) reflectance data. The mixtures of different proportions of plaster and allochite were analyzed to estimate the accuracy of the spectral unmixing model based on DRS. For the best 5 strong linear bands, the Pearson correlation coefficient (PCC) of the abundances and the actual abundances were higher than 99.9%, while the root mean square error (RMSE) is less than 2.2%. The result shows that the new spectral unmixing model based on DRS is simple, of rigorous mathematical proof, and highly precise. It has a great potential in high-precision quantitative analysis of spectral mixture with fixed endmembers.

[Fresh and frozen-thawed meat discrimination based on FISS imaging spectral data].

In the present paper, a self-developed Field imaging spectrometer system (FISS) was used to detect whether pork has been frozen and thawed. The preservation time of fresh pork has also been identified. Fresh and frozen-thawed pork was scanned and imaged and hyperspectral image cubes were acquired using FISS. To eliminate high-frequency random noise and baseline offset and improve the multi-collinearity, all samples were preprocessed by MNF (Minimum noise fraction) transform and first derivative. Multiple analysis models were built by using Wilks' lambda stepwise method to select proper wavelengths. Fisher LDA (linear discriminant analysis) was performed to discriminate fresh and frozen-thawed pork. Eight selected bands gave 99% correct results of fresh or frozen-thawed pork samples. For the freshness by the day, classification accuracy reached 98% with 6 selected bands, while for the freshness by the hour, classification accuracy reached 93.6% with all 28 selected bands. The results showed that FISS might be used as a screening method to identify the quality of meat.

[Study on discrimination of varieties of milk based on FISS imaging spectral data].

Using a self-developed field imaging spectrometer system (FISS), hyperspectral images of 14 typical kinds of milk were acquired, based on which the discrimination of varieties of milk was studied. Firstly, removing 2 abnormal samples, the remaining 12 kinds of milk were randomly sampled, a total of 1 200 pixel samples. To eliminating high-frequency random noises and baseline offset and decrease the multi-collinearity, all samples were preprocessed by smooth-moving average and first derivative. Secondly, multiple discriminant analysis models for milk were built using characteristic wavelengths selected by the stepwise method. Results demonstrated that the overall identification accuracy for 1 200 spectral samples put together reached 95.5%, of which the overall distinguishing rate of Mengniu, Yili and Guangming acidophilous milk was 88.3%. The discriminant models for the three kinds of acidophilous milk subset, 300 spectral samples in all, were built, with the overall distinguishing rate of 88.7%. This explicated that FISS would be useful for discriminating milk varieties, and to accomplish specific discrimination of milk varieties, it would be best for milk of the same type from different manufacturers to form a subset, which may not only reduce the model variables, improving operational efficiency and the stability of the model, but improve their overall discriminant accuracy.