ABSTRACT
Objective@#To explore the prevalence of health risk behaviors and the association between locus of control and health risk behaviors among college students, and to provide reference for the formulation of health risk behavior intervention for college students.@*Methods@#A multi stage cluster random sampling method was used to select 2 provinces from the east, central and west regions of China, respectively. Two universities were then randomly selected from each selected province. A total of 3 951 college students from 12 universities completed the electronic and anonymous questionnaires, which included demographic characteristics, Multidimensional Health Locus of Control Questionnaire (MHLC) and Health Risk Behaviors Questionnaire. Chi square test and binary Logistic regression were applied to analyze data.@*Results@#Totally 2 287(57.88%) students reported having three or more kinds of health risk behaviors. The prevalence of excessive screen time, insufficient physical exercise, poor eating behaviors, drinking and smoking were 97.34%(3 846), 74.72%(2 952), 72.21%(2 853), 13.62%(538) and 5.57%(220). Internal locus of control was associated with lower risk of three or more kinds of health risk behavior ( OR =0.98) and inadequate physical activity ( OR =0.93) and associated with higher risk of smoking ( OR =1.07). The powerful others was associated with lower risk of three or more kinds of health risk behavior ( OR =0.98), drinking ( OR =0.95) and unhealthy eating behavior ( OR =0.97). And the chance was associated with higher risk of three or more kinds of health risk behavior ( OR = 1.04 ), drinking ( OR =1.04) and inadequate physical activity ( OR =1.03)( P <0.01).@*Conclusion@#College students have serious health risk behavior problems, the locus of control is associated with health risk behaviors among college students. Which might be helpful to prevent the occurrence of health risk behaviors, and improve overall health of college students.
ABSTRACT
Objective@#To investigate the prevalence and influencing factors of suicidal ideation and the effects of daily stress and positive mental health on suicidal ideation among college freshmen in Wuhan. This study aims to provide a scientific basis for mental health improvement and suicide prevention among college students from the perspective of positive psychology.@*Methods@#In December 2020, a convenient sampling method was used to select 2 592 freshmen from three universities in Wuhan. Demographic information, suicidal ideation, positive mental health, and daily stress were assessed. T test and Logistic regression analysis were used to analyze the status and influencing factors of suicidal ideation among college freshmen.@*Results@#The one year prevalence of suicidal ideation was 27.5%. Freshmen with suicidal ideation had higher daily stress scores and daily stress scores in different domains than freshmen without suicidal ideation( t =-13.00--4.68)， the positive mental health scores of freshmen with suicidal ideation were lower than freshmen without suicidal ideation ( t =17.14， P <0.01). Female ( OR=1.72, 95%CI =1.44-2.05), the higher education level of the mother (OR=1.27, 95%CI=1.05-1.53) and total experience of daily stress ( OR=1.11, 95%CI =1.09- 1.13 ) were associated with risk of oneyear suicidal ideation. Positive mental health was negatively associated with suicidal ideation ( OR=0.88, 95%CI=0.87-0.90, P <0.01) and had a moderating effect on the association between daily stress and suicidal ideation.@*Conclusion@#Suicidal ideation among college freshmen is closely related to daily stress and positive mental health. It is necessary to pay close attention to daily stress of freshmen and reduce suicidal ideation by improving positive mental health.
ABSTRACT
The gene dhaT from Klebsiella pneumoniae encoding 1,3-propanediol oxidoreductase (PDOR) was de novo synthesized by splicing overlap extension polymerase chain reaction (SOE-PCR) primarily according to Escherichia colis codon usage, as well as mRNA secondary structure. After optimization, Codon Adaptation Index (CAI) value was improved from 0.75 to 0.83, meanwhile energy of mRNA secondary structure was increased from -400.1 to -86.8 kcal/mol. This synthetic DNA was under control by phage T7 promoter in the expression vector pET-15b and transformed into the E. coli BL21 (DE3) strain. Inducers such as isopropyl beta-D-thiogalactoside (IPTG) and lactose were compared by activity at different inducing time. The activity of PDOR after codon optimized was 385.4 +/- 3.6 U/mL, which was almost 5-fold higher than wild type (82.3 +/- 1.5 U/ml) under the flask culture at 25ºC for 10 hrs. Then his-tagged enzyme was separated by using Ni-IDA column. The favorite environment for enzyme activity was at 5°C and pH 10.0, PDOR showed a certainly stability in potassium carbonate buffer for 2 hrs at diverse temperatures, enzyme activity was significantly improved by Mn2+.