1. Introduction

It is well known that the health-care system is confronted with a shortage of nurses in the workforce and that it is facing rapidly increasing needs for patient care in an aging population.1,2 This situation has made the nursing profession more stressful and susceptible to turnover.3 Studies have shown that the average turnover rate for nurses in Canada is 19.9%.4 Nurses’intention to leave their profession varied from 5% to 17% in European countries.5 Slightly more than half(50.2%) of the nurses in Ethiopia reported the same intention.6 China is a populous country, but it also has an aging population; the circumstances may be more serious in China. Turnover intention is the main predictor of turnover action,7 which affects not only nurses’ mental health but also their work efficiency and service quality. In recent years, there have been studies about turnover intention in many countries.Most studies focus on risk factors and negative interventions associated with turnover intentions. Hence,the research on individuals’ active initiatives remains to be enriched.

Burnout is defined as a response to ongoing stress or psychological strain.8 Employee burnout can trigger turnover challenges for leaders and institutions.Previous literature has reported that burnout positively affects turnover intentions.9 “Turnover intentions” refers to a psychological tendency that could lead to turnover behaviors when employees are not satisfied in their work.10

下面这一例证，既体现了以“孝”治天下在东晋的真正落实，即使皇帝也必须以身作则，否则便无资格君临天下；又旁证了在这一时期君臣上下已就儒家这一治国理念达成高度一致；更凸显了汉魏之际、魏晋之际所少有的东晋士大夫集团为捍卫衰微王权而面斥权臣的“忠贞”群体，尤其温峤不畏强暴、不顾身之安危的凛然臣节，没有对忠义、诚信的道德信仰，是很难做到的。

With the rise of positive psychology, researchers have begun to explore job burnout and turnover intention from a new perspective, highlighting the development of individual potential and the exploration of mental resources.11 “Positive emotions” is a category of positive psychology. It refers to an individual’s subjective experi-ence and indicates a temporary or persistently positive emotional state. It can increase psychological flexibility and help a person maintain good mental health. Previous literature has reported that positive emotions are significantly, negative correlated with burnout,12 possibly reducing burnout and serving as the controlling factor in burnout. Thus, we suggest that positive emotions mediate the relationship between burnout and turnover intentions.

结合图2、图5、图6可以看出，沉管周围尤其底板处海床循环剪应力比较大，这也解释了沉管近、远场海床液化发展规律的差异。

Recently, there have been many studies written from the perspective of positive psychology, which focus on ways to decrease turnover intentions.13,14 The purpose of our study was to investigate the relationships among burnout, positive emotions, and turnover intentions in nurses in China. We wanted to know the influence of burnout and positive emotions on nurses’ turnover intentions.

2. Methods

2.1 Design and sample

2.2.4 Positive emotion

矿区位于江南古陆南缘、右江再生地槽北部边缘的丹池多金属成矿带上。带上等间距分布着3个主要多金属矿田：芒场矿田、大厂矿田、五圩矿田，相距各30～5km箭猪坡矿床位于五圩矿田中东部(图1)。

2.2 Instruments

The research tools used in this study include four parts:(a) demographic information; (b) Turnover Intentions Scale; (c) Burnout Scale; and (d) Positive Affect and Negative Affect Scale.

2.2.1 Nurses’ demographic information

Nurses’ demographic data included personal details such as age, gender, marital status, and education level. These demographic data are potential variables influencing burnout, turnover intentions, and positive emotion.

n our study, the job burnout of Chinese nurses was more serious, and the level of turnover intentions was higher.This suggested that Chinese nurses’ turnover intentions should not be ignored, and that it is imperative to find an effective intervention strategy. Our results also showed that burnout was positively associated with nurses’ turnover intentions, results consistent with the research by Han et al.21 It is possible that nurses who have high levels of burnout cannot face life events calmly nor can they actively address the pressure and stressors.Our findings also suggested that a negative correlation exists between positive emotions and nurses’ turnover intentions; in other words, when individuals have more positive emotions and use resources to face the challenges and opportunities of life, their life satisfaction is enhanced and their willingness to quit is reduced. It is possible that positive emotions can enhance individuals’ positive adaptations to frustration and their ability to cope effectively with challenges, give positive meaning to stressful events, enable working closely with others,and help actively solve core problems.22

This study has obtained the consent of the medical ethics committees of the participating hospitals and the authors’ university. The participants were informed that involvement was absolutely voluntary and that they could drop out of the survey at will at any time with no adverse ramifications.

Positive emotion mediates the relationship between burnout and nurses’ turnover intention in China. It is believed that nursing administrators should pay more attention to the benefits of positive emotion for working motivation. It is meaningful to relieve burnout in the working process so that nurses are willing to stay in their current employment.

2.2.3 Turnover intentions

To evaluate the turnover intentions of nurses, the version of the three-items scale developed by Luthans and Jensen17 was used. Items included the following statements: “If I can choose now, I want to change to other work outside nursing; “As for me, my work is the best at present”; “Choosing to work here now seems like the wrong choice.” Respondents were asked to rate each item by selecting one of six options, ranging from one(strongly disagree) to six (strongly agree). The scores were recorded, with higher scores indicating higher levels of intention to leave the hospital. The Cronbach’s αof the total scale was 0.87.

A cross-sectional design with self-reported questionnaires was utilized in this survey. A sample of 150 registered nurses from Grade A hospitals in Tianjin was surveyed. Electronic questionnaires and paper questionnaires were posted to approximately 200 nurses in August 2015. Because some nurses were busy with work and family, some questionnaires were not handed back. In all, 160 questionnaires were completed, a reclamation rate of 80%. Ten of the completed questionnaires were excluded for missing data. Overall, the sample size included in this study was 150; the valid reclamation rate was 75%. Females accounted for 98% of all participants; 18% of participants were ＞25 years of age, and 43.3% held a bachelor’s degree.

研究表明每生产100 kg黍子籽粒大约从土壤中吸氮8.0-2.1 kg、磷0.8-1.0 kg、钾1.21-1.8 kg。基肥：播种前结合深耕施入，以有机肥为主，有机肥营养全面，肥效长，促进土壤熟化，提高土壤肥力，基肥施用时间以秋施或早春施较好，一般有机肥1500-2000 kg，并注意施N、P，复合肥15-20 kg。种肥：供黍子前期生长用，以氮肥为主，尿素1 kg，硫酸铵2.5 kg，磷酸铵1.5-2.5 kg每亩。

Furthermore, we examined the significance of the mediating effects of positive emotion through a Sobel test.20 The results fully supported the hypothesis that positive emotion mediates burnout and nurses’ turnover intentions (z = 2.69; P = 0.001).

2.3 Ethical considerations

We measured nurses’ burnout with the scale of the Chinese version of the Maslach Burnout Inventory - General Survey (MBI-GS),15 which consisted of 15 items and three dimensions, including emotional exhaustion, cynicism, and reduced professional efficacy. The Chinese version of MBI-GS has been verified as a high-reliability tool.16 In this study, the total Cronbach’s α was 0.86, and the Cronbach’s α of the dimensions ranged from 0.82 to 0.88. Respondents answered using a seven-point Likert scale, ranging from zero (“never”) to six (“every day”).Higher scores show a more serious level of burnout.

2.4 Statistical analysis

All analyses were performed using the SPSS 17.0 program, and all statistical tests were two-sided (α = 0.05).Descriptive statistics were used to summarize sample characteristics. Pearson correlation analysis was performed for testing the relationships among all variables. Hierarchical regression was used for testing the hypotheses of the mediating effects of positive emotion on burnout and turnover intention. The Sobel test was further used to prove the significance of the mediating effects of positive emotion.

3. Results

3.1 The demographic characteristics of nurses

The demographic characteristics of the participants are shown in Table 1. The respondents included 150 nurses. Of these, 89 nurses were unmarried (59.3%).Females accounted for 98% of the participants, 18%were ＞25 years of age, and 43.3% held a Bachelor’s degree.

本节分析比较参数α对本文算法检索性能的影响.在α有效范围内，50个查询在3个数据集m0、m1和k1中进行本文算法实验，其检索结果MAP值如图2至图4所示.其中，实验参数：ms=0.2，mc=0.8，Litem =2,minPR=0.1，minNR= 0.01.图例中， “t” 和“d”分别表示TITLE和DESC查询，“e”代表Relax值，表Rigid值，“A”代表PTAE_AWPNP算法，“C”代表PTCE_AWPNP算法.

Table 1. Demographic characteristics of the participants

Variables Number of participants %Gender Female 147 98.0 Male 3 2.0 Marital status Married 61 40.7 Single 89 59.3 Age group (in years)20–25 123 82.0 26–30 23 15.3 31–35 4 2.7 Education Technical secondary school 9 6.0 Junior college 76 50.7 Bachelor 65 43.3

3.2 The mean values, standard deviations,and correlation analysis among burnout,positive emotions, and turnover intentions

Pearson’s correlation test was performed to examine the relationships among burnout, positive emotions, and turnover intentions of nurses. The results in terms of the mean values, standard deviations, and all the variables’Pearson correlations are illustrated in Table 2. These variables, including burnout, positive emotions, and turnover intentions, were statistically significant effects and showed correlated relationships.

3.3 Testing the hypothesized mediating effects of positive emotions

To verify the mediating effects of positive emotions between burnout and nurses’ turnover intentions, a multistep process was applied by Wen et al.19 Under the influence of controlling demographic variables, we examined the possible mediating effect of positive emotions on nurses’ burnout and turnover intentions. The first step was to investigate the predictive effect of job burnout on turnover intentions. The second step was to investigate the predictive effect of job burnout on positive emotions. The third step was to investigate the predictive effect of job burnout and positive emotion on turnover intentions. Table 3 shows that job burnout can effectively predict turnover intentions and positive emotions after controlling for the influence of demographic data. Further analysis showed that the predictive effect of job burnout on turnover intentions is still significant,but the predictive power is reduced; the prediction effect of positive emotion on turnover intentions is significant after controlling for the influence of demographic variables and positive emotion. Positive emotion had a partial mediation effect between nurses’ job burnout and turnover intentions, and the mediation effect accounted for 35% of the total effect.

Table 2. Pearson’s correlation test of relationships among burnout, positive emotions, and turnover intentions of nurses

Notes: ＊P ＜ 0.05; ＊＊P ＜ 0.01. M = mean value; SD = standard deviation.

M SD 1 2 3 4 5 6 1. Burnout 67.176.741–––––2. Exhaustion 19.211.620.0451––––3. Cynicism 15.711.700.0300.1241–––4. Professional efficacy 24.93 1.89 –0.125 –0.016 –0.163＊ 1 – –5. Positive emotion 15.35 2.40 –0.826＊＊ –0.013 –0.010 0.084 1 –6. Turnover intention 16.29 0.62 0.926＊＊ 0.001 0.047 –0.080 –0.893＊＊ 1

Table 3. Mediating effects of positive emotion on burnout and nurses’ turnover intentions

Notes: ＊＊P ＜ 0.01; SE = standard error; B-value = unstandardized B.

Variables Step 1: turnover intentions Step 2: positive emotion Step 3: turnover intentions B-value SE β-value B-value SE β-value B-value SE β-value Gender –0.121 0.135 –0.027 0.529 0.812 0.031 –0.067 0.108 –0.015 Age 0.030 0.010 0.108＊＊ –0.049 0.058 –0.045 0.025 0.008 0.091＊＊Marital status –0.043 0.043 –0.035 0.210 0.259 0.043 –0.022 0.035 –0.018 Education 0.053 0.033 0.051 –0.180 0.197 –0.045 0.035 0.026 0.034 Burnout 0.085 0.003 0.926＊＊ –0.295 0.017 –0.829＊＊ 0.055 0.004 0.602＊＊Positive emotion – – – – – – –0.100 0.011 –0.391＊＊R2-value 0.868 0.688 0.916 F-value 189.948＊＊ 63.384＊＊ 260.429＊＊

Positive emotion was measured using the Chinese version of the Positive Affect and Negative Affect Scale(PANAS).18 We used only Positive Affect, which includes nine items. Respondents rated each item on a five-point Likert scale, ranging from one (not very strong) to five(very strong). In this study, the Cronbach’s αof the scale was 0.85. Higher scores indicated greater job enthusiasm.

4. Discussion

I

2.2.2 Burnout

The proposed mediating effects of positive emotion were also supported by our data. The results showed that positive emotion mediated the relationship between burnout and nurses’ turnover intention. This also suggested that positive emotions played an important role in burnout and turnover intention. Over time, the positive emotions experienced by individuals can be superimposed and can help to build many personal resources,such as enhanced positive beliefs, life goals, and social support, in addition to alleviating symptoms of illness.On the other hand, personal resources and enhanced individual life satisfaction reduce symptoms such as anxiety, helping the individual attain a higher level of positive emotions and psychological state, thus reducing the occurrence of job burnout and turnover intention.23

5. Conclusions

张连长带着知青们走在山脚下的公路上。而所谓公路,其实只不过是包括拖拉机在内的各种大大小小的车辆压出来的一条土路。

Conflicts of interest

All contributing authors declare no conflicts of interest.

Acknowledgments

The authors gratefully acknowledge the supervisors and all employees who participated in this study for their assistance, as well as the experts and members of our group for their help and advice.

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