Religion, Psychological Strain, and Suicidality in China: A Preliminary Study

BACKGROUND

There is a lack of religiosity studies in China especially in relation to mental health and suicidality. In this research, we focus our studies on medical workers of which some studies reported to have higher stress, and to pilot our studies in this adult age-group.

DATA AND METHODOLOGY

Data were obtained by a questionnaire survey in a large public hospital in a big metropolitan city of China. The final sample consisted of 1012 respondents with 237 (23.4%) being male and 775 (76.6%) being female. The respondents were of three groups: (1) Believers (n = 34; 3.5%); (2) Non-Believers or Atheists (n = 547; 55.8%); and (3) Agnostics or Fence-Sitters (n = 400; 40.8%). Suicidality was measured by the NCS-Suicidality Scale, and standard measures were employed for other major variables.

FINDINGS

In line with other recent studies in China, the religion rate among the urban adults remained low (3.5%). However, about 40.8% of the respondents chose "don't know" and could be fence-sitters on the issue of religious belief. Many of them are involved in various folk beliefs which may not be considered as religious. The religious believers were at higher risk of suicidality and depression than the atheists and the fence-sitters. However, the fence-sitters were higher than the believers and atheists on psychological strains, and they were higher on depression compared to the atheists.

CONCLUSION

The religious believers and religious fence-sitters have higher psychopathologic risks and suicidal risk than the atheist group. Religion as of low prevalence in Chinese societies is a social value deviant from the norm and its practitioners are likely to be marginalized or stigmatized. The Strain Theory of Suicide is used for detailed explanations.

Ammonia gas treatment in low cost biological reactor

Ammonia gas contributes to a number of environmental and human health concerns. The use of chalk, a cheap alkalinity source may reduce costs for biological systems. This research studies a closed liquid flow reactor to treat ammonia gas using chalk as biomass media and alkalinity source with high value calcium nitrate fertilizer production. The proposed reactor showed complete ammonia gas removal at high rate (500 mg N/L/day) and with low cost; where chalk dissolution and ammonia gas absorption contributed to alkalinity in the water for nitrification. High calcium ion concentration (up to 10,000 mg Ca2+ as CaCO3/L) showed only minor effects on ammonia absorption and nitrification rate.

Associations among Distress Rumination, Somatic Anxiety, and Suicidal Ideation in Chinese College Students - Shandong Province, China, 2019-2020

What is already known about this topic?

The literature has consistently demonstrated that distress rumination following a traumatic event has significant implications for mental health. However, the potential association between distress rumination and suicidality, as well as the underlying mechanisms driving this relationship, remains to be elucidated.

What is added by this report?

The current study demonstrated a significant, positive correlation between distress rumination and suicidal ideation in college students who have encountered traumatic events. The findings indicate that somatic anxiety serves as a mediator between distress rumination and suicidal ideation.

What are the implications for public health practice?

Interventions aimed at reducing somatic anxiety may contribute to a decrease in suicidal ideation. Assessing and addressing somatic anxiety symptoms in college students experiencing distressful rumination following traumatic events could potentially lower the risk of suicide.

Decriminalizing suicide attempt in the 21st century: an examination of suicide rates in countries that penalize suicide, a critical review

BACKGROUND

Decriminalizing suicide may decrease overall suicide rates because then individuals who are at risk of suicide would be more willing to seek help from the community and from mental health professionals, therefore enabling early interventions for preventing suicidality. We aimed to examine the suicide trends over the last 20 years in 20 countries that still criminalize attempted suicide, and to compare the suicide rates of these 20 countries against the global average suicide rate and to a comparison sample of 20 countries that do not criminalize suicide, matched according to region and majority religion.

METHODS

Age-standardized suicide rates were extracted from the WHO Global Health Estimates, available for the period 2000-2019. Population data were extracted from the World Bank. We analyzed only countries which criminalize attempted suicide under its criminal justice system. Countries were further categorized according to their membership in the Commonwealth of Nations and countries in Africa. Countries from the same region and with the same majority religion were chosen as a matching group. Joinpoint analysis was used to compare the trends of the two groups with the global average.

RESULTS

Based on the 2019 WHO Global Health Estimates data, there is a large range in the suicide rates of the countries that criminalize attempted suicide, from 2.5 (Brunei) to 40.9 (Guyana) per 100,000 population. The mean suicide rate was 8.3 (Standard Deviation = 10.6). Out of the 20 countries, seven have suicide rates higher than the global average, covering a total population of about 387.3 million. Of these seven countries, five are in the African region. The other thirteen countries have suicide rates between 2.5 to 8.2. Mean scores of the countries which criminalized attempted suicide was lower than the global average and 20 comparison countries over the 20 years, but average annual percentage in the decrease of suicide was greater for countries in which attempted suicide was not criminalized.

CONCLUSIONS

Based on our review, there was no substantial evidence here to indicate that countries which criminalized attempted suicide had consistently lower suicide rates compared to the global average. There is a need to acknowledge that the currently available evidence is inadequate to definitively claim that criminalizing suicide is beneficial or harmful for the reduction of suicide rate for the entire populations. Future studies should continue to evaluate the unique effects of decriminalizing attempted suicide while controlling for other key associated factors.

An analysis of age-standardized suicide rates in Muslim-majority countries in 2000-2019

BACKGROUND

This study examines the 20-year trend of suicide in 46 Muslim-majority countries throughout the world and compares their suicide rates and trends with the global average. Ecological-level associations between the proportion of the Muslim population, the age-standardized suicide rates, male-to-female suicide rate ratio, and the Human Development Index (HDI) in 2019 were examined.

METHODS

Age-standardized suicide rates were extracted from the WHO Global Health Estimates database for the period between 2000 and 2019. The rates in each country were compared with the age-standardized global average during the past 20 years. The countries were further grouped according to their regions/sub-regions to calculate the regional and sub-regional weighted age-standardized suicide rates involving Muslim-majority countries. Correlation analyses were conducted between the proportion of Muslims, age-standardized suicide rate, male: female suicide rate ratio, and the HDI in all countries. Joinpoint regression was used to analyze the age-standardized suicide rates in 2000-2019.

RESULTS

The 46 countries retained for analysis included an estimated 1.39 billion Muslims from a total worldwide Muslim population of 1.57 billion. Of these countries, eleven (23.9%) had an age-standardized suicide rate above the global average in 2019. In terms of regional/sub-regional suicide rates, Muslim-majority countries in the Sub-Saharan region recorded the highest weighted average age-standardized suicide rate of 10.02/100,000 population, and Southeastern Asia recorded the lowest rate (2.58/100,000 population). There were significant correlations between the Muslim population proportion and male-to-female rate ratios (r=-0.324, p=0.028), HDI index and age-standardized suicide rates (r=-0.506, p<0.001), and HDI index and male-to-female rate ratios (r=0.503, p<0.001) in 2019. Joinpoint analysis revealed that seven Muslim-majority countries (15.2%) recorded an increase in the average annual percentage change regarding age-standardized suicide rates during 2000-2019.

CONCLUSIONS

Most Muslim-majority countries had lower age-standardized suicide rates than the global average, which might reflect religious belief and practice or due to Muslim laws in their judicial and social structure which may lead to underreporting. This finding needs further in-depth country and region-specific study with regard to its implication for public policy.

Towards Higher Psychometric Properties: Testing the Psychological Strain Scales with Larger Samples

This study aimed to further test the psychometric properties of the Psychological Strain Scales (PSS) with larger samples. A cluster sampling method was employed to recruit 13,250 college students from seven provinces in China. Descriptive statistics, item statistics, Cronbach's alpha, factor analysis, and correlation analysis were evaluated. Cronbach's alpha coefficient was 0.958 and Guttman's split-half coefficient was 0.866. All the item-total correlations were larger than 0.45 except one. Results from Exploratory Factor Analysis and Confirmatory Factor Analysis supported the four dimensions of psychological strains (value strain, aspiration strain, deprivation strain, and coping strain). The PSS was strongly correlated to the Depression, Anxiety, and Stress Scale (DASS-21), which was commonly used to measure risk for suicide and was predictive ofsuicidality as measured by the SBQ-R. The PSS was a self-report instrument with high reliability and validity which could be applied for extensive use in research to measure psychological strains.HighlightsThis is the first study testing the psychometric properties of the PSS in an unusually large sample.Confirmatory factor analysis was applied to provide empirical evidence to the four-factor structure of the PSS.Psychological strains were found to be significantly correlated with depression, anxiety, and stress symptoms and predictive of suicidality.

The Relationship Between Negative Focused Disposition and Suicidal Ideation Among College Students: The Mediating Effects of Somatic Anxiety, General Distress, and Depression

OBJECTIVE

Suicide among college students is a major public health problem. Research has confirmed that negative focused disposition had a significant effect on suicidal ideation. This study aims to evaluate somatic anxiety, general distress and depression as mediators of the relationship between negative focused disposition and suicidal ideation.

METHODS

A total of 1798 college students (942 males) were recruited to complete measures of negative focused disposition, somatic anxiety, general distress, positive affect and suicidal ideation. The mediation models were conducted to assess the mediating effects of somatic anxiety, general distress and depression.

RESULTS

There was a significant and positive correlation between negative focused disposition and suicidal ideation in Chinese college students. On mediation analysis, somatic anxiety, general distress and depression mediated the relationship between negative focused disposition and suicidal ideation.

CONCLUSIONS

Negative focused disposition appears to directedly associate with suicidal ideation and can indirectly relate to suicidal ideation through the relation with somatic anxiety, general distress and depression. College students with few positive expectations of the future may benefit from interventions focusing on somatic anxiety, general distress and depression.

Religion, Strain and Suicidality among Chinese Young Adults

This study examined the mediating effects of psychological strain (Strain Theory) as a possible explanation for the relationship between religiosity and suicidality among Chinese young adults. A questionnaire was administered that included the Religious Orientation-Revised Scale (RO-RS), Suicidal Behaviors Questionnaire-Revised (SBQ-R), and Psychological Strains Scale (PSS). Using cluster sampling, we recruited 13,250 college students across seven provinces in China. Both univariate and multivariate analyses were used to identify the main determinants of suicidality. We further explored the mediation effect of psychological strains on the relationship between religion and suicidality. We found that non-believers obtained the lowest PSS. Believers of Islam and other religions obtained higher RO-RS scores compared to non-religious participants. Psychological strain imposed a complete effect between religiosity and suicidality. A positive relationship between religion and suicidality was present among the participants of the study. Individuals who are affiliated with a religion are considered as a marginalized population in China, which may lead to psychological strains, further increasing the risk of suicidality.

Religious affiliation and suicidality among college students in China: A cross-sectional study across six provinces

BACKGROUND

Several past studies indicated that religious beliefs, orientation, and practice are protective of suicide. Findings from recent studies in China suggest that religiosity may contribute to increased suicidality. However, few studies have examined the associations between religious affiliation across different faiths and suicidality in China.

OBJECTIVE

The current study examines the association between religious affiliation and suicidality among college students in six provinces in China.

METHODS

We conducted a cross-sectional study involving 11,407 college students from six universities in Ningxia, Shandong, Shanghai, Jilin, Qinghai, and Shaanxi. We collected the data between October 2017 and March 2018 using self-report questionnaires. They included self-report measures of depression, psychache, hopelessness, self-esteem, social support, and life purpose.

RESULTS

Participants with a Christian affiliation had 1.5 times (95% CI: 1.14, 1.99, p = 0.004) higher odds of indicating an elevated suicide risk, 3.1 times (95% CI: 1.90, 5.04, p<0.001) higher odds of indicating a previous suicide attempt, and increased overall suicidality (B = 0.105, p < 0.001) after accounting for demographic and risk/protective factors. Christians also scored the highest in depression, psychache, hopelessness, and the lowest social support, self-esteem, and purpose in life. Muslims reported decreased suicidality (B = -0.034, p = 0.031). Buddhism/Daoism yielded non-significant results in the multivariate analyses.

CONCLUSIONS

Christian college students reported increased suicidality levels, perhaps due to public policies on religion. The decreased suicidality levels among Muslims may be attributed to higher perceived social support. The associations between religious affiliation and suicidality, depression, and hopelessness contrast sharply with US samples. This finding may be influenced by interactions between the religious denomination, individual, and social/political factors. This conclusion includes the possibility of anti-religious discrimination, which this paper did not investigate as a possible mediator and therefore remains a conjecture worthy of future investigation.

Using Contemporary Psychometric Methods to Construct and Validate Scores on a Short-Form Version of the Psychological Strain Scales

BACKGROUND

The 40-item Psychological Strain Scales (PSS) was developed to measure four dimensions of psychological strains based on the Strain Theory of Suicide. Although the PSS has been increasingly used in recent years, the dimensionality and scoring of the PSS remained to be thoroughly examined using the Item Response Theory (IRT) approach.

METHODS

Data came from a large sample of 11,412 Chinese undergraduate students. A bifactor-IRT model, specifying one general strain factor and four specific strains factors, was examined for fit to the sample data. A detailed item analysis, with analysis of the differential item functioning (DIF) of the items across gender, was undertaken to evaluate the dimensionality of the PSS. The associations among the PSS scale scores with scores on the concurrent measures, assessing psychache and suicidal behaviors, were examined.

RESULTS

IRT-derived specific bifactor indices showed that the PSS was unidimensional, and thus the PSS total scores should be reported. Unidimensional subset of 5 items identified (Item 9, Item 12, Item 14, Item 16, and Item 20), using bifactor-IRT modeling and incremental validation, were selected to construct a potential short form of the PSS (PSS-SF). The PSS-SF scale scores demonstrated strong psychometric properties and associations with scores on the concurrent measures assessing relevant constructs.

LIMITATIONS

This study used cross-sectional data from a non-clinical sample of Chinese undergraduate students.

CONCLUSIONS

The PSS-SF should be considered as a unidimensional instrument with potential in enhancing our understanding and measurement of psychological strains with reduced response burden.

Psychological characteristics of suicide attempters among undergraduate college students in China: a cross-sectional study

BACKGROUND

There is a need to understand the psychological characteristics of suicide attempters to prevent future suicide attempts. This study aims to examine potential differences between individuals who have attempted suicide and those who have not done so, on several risk and protective measures.

METHOD

Participants were 11,806 undergraduate students from seven provinces in China, of which 237 reported a non-fatal suicide attempt. We used the random numbers generator function within the SPSS to randomly select a control subset of 1185 participants to be used as the comparison group based on a 1:5 case-control ratio. Scores on three commonly used risk measures (depression, hopelessness, and psychache) and three protective measures (social support, self-esteem, and purpose in life) for suicidality were adopted to compare the responses of the two groups.

RESULTS

Suicide attempters had indicated higher Median scores for all three risk factor measurements. Suicide attempters also reported significantly lower Median scores for all three protective factor measurements compared to non-suicide attempters. The results suggest that the suicide attempters' group had higher risks of suicidality compared to the non-attempter group.

CONCLUSIONS

Suicide attempters continued to report higher scores of risk factors and lower scores of protective factors, indicating that they may continue to be at a higher likelihood of a suicide attempt. Key protective factors should be identified for each individual in order to deliver appropriate clinical interventions to reduce their risk of reattempting.

Looking Into Recent Suicide Rates and Trends in Malaysia: A Comparative Analysis

Background: Suicide is a preventable cause of death. Examining suicide rates and trends are important in shaping national suicide prevention strategies. Therefore, the objectives of this study were to analyze age-standardized suicide trends of Malaysia between 2000 and 2019 using the WHO Global Health Estimates data, and to compare the 2019 rate with countries from the Association of South-East Asian Nations (ASEAN), Muslim majority countries, and the Group of Seven (G7). Methods: The age-standardized suicide rates data were extracted from the WHO Global Health Estimates. We calculated the average age-standardized suicide rates of the last 3 years from 2017 to 2019. Joinpoint regression analysis was conducted to calculate the average annual percentage change (APC) of the age-standardized suicide rates in Malaysia from 2000 to 2019. Results: Between 2000 and 2019, the minimum and maximum suicide rates for both sexes in Malaysia were 4.9 and 6.1 per 100,000 population respectively, whilst the past 3-year (2017-2019) average rates were 5.6, 8.8, and 2.4 for both sexes, males, and females, respectively. The suicide rates decreased significantly for both sexes between 2000 and 2013. Between 2014 and 2019, the suicide rates increased significantly for males. In 2019, Malaysia recorded the rate of 5.8 per 100,000 population, with an estimated 1,841 suicide deaths, i.e., ~5 deaths per day. The Malaysian suicide rate was the second highest amongst selected Muslim majority countries, in the middle range amongst ASEAN countries, and lower than all G7 countries except Italy. Conclusions: There is a need to further explore factors contributing to the higher suicide rates among Malaysian males. In light of the rising suicide rates in Malaysia, national mental health and suicide prevention initiatives are discussed and the importance of high-quality suicide surveillance data is emphasized.

Suicidality among Chinese college students: A cross-sectional study across seven provinces

Background

Although the suicide rate in China has decreased over the past 20 years, there have been reports that the younger age group has been experiencing an increased incidence of completed suicide. Given that undergraduate groups are at higher risks of suicidality, it is important to monitor and screen for risk factors for suicidal ideation and behaviors to ensure their well-being.

Objective

To examine the risk and protective factors contributing to suicidality among undergraduate college students in seven provinces in China.

Methods

We conducted a cross-sectional study involving 13,387 college students from seven universities in Ningxia, Shandong, Shanghai, Jilin, Qinghai, Shaanxi, and Xinjiang. Data were collected using self-report questionnaires.

Results

Higher scores in the psychological strain, depression, anxiety, stress, and psychache (psychological risk factors for suicidality) and lower scores in self-esteem and purpose in life (psychological protective factors against suicidality) were associated with increased suicidality among undergraduate students in China. Demographic factors which were associated with higher risks of suicidality were female gender, younger age, bad academic results, were an only child, non-participation in school associations, and had an urban household registration. Perceived good health was protective against suicidality.

Conclusions

Knowing the common risk and protective factors for suicidality among Chinese undergraduate students is useful in developing interventions targeted at this population and to guide public health policies on suicide in China.

A comparison between American and Chinese college students on suicide-related behavior parameters

BACKGROUND/OBJECTIVE

The United States (US) and China are the two largest economies, but recent and directly comparable studies on suicide-related behaviors in the two countries are lacking. By using the Suicidal Behaviors Questionnaire-Revised (SBQ-R), item-level comparison was performed in assessing self-reported suicide-related behaviors between the US and Chinese undergraduates.

METHOD

This study involved a total of 3,185 college students aged between 18 to 24 years (1,185 US college students, and 2,000 Chinese students who were randomly selected from a large sample of 11,806 Chinese college students). Participants filled out the 4-item SBQ-R.

RESULTS

Participants' responses were compared by country and sex. There was a higher overall risk of suicide-related behaviors among US students (24.3%) compared to Chinese students (17.0%). US students also reported higher lifetime attempt, past-year ideation, and lifetime threat. US female college students reported the highest suicide-related behaviors compared to other sub-groups.

CONCLUSIONS

There is a need to tailor specific interventions to alleviate college students' suicide-related behaviors in the US and China, with a particular focus on US females.

Shame and Suicidal Ideation among Undergraduates in China: The Mediating Effect of Thwarted Belongingness and Perceived Burdensomeness

Undergraduate students with shame are more likely to experience suicidal ideation, but there remains a lack of research investigating the factors underlying this relationship. The interpersonal theory of suicide posits that suicidal ideation is influenced by the simultaneous presence of thwarted belongingness and perceived burdensomeness. We examined the prevalence of suicidal ideation among undergraduate students in China and examined the association between shame and suicidal ideation mediated by perceived burdensomeness and thwarted belongingness. A survey was conducted in July 2018 involving 2320 undergraduate students, and the twelve-month prevalence of suicidal ideation was 8.95%. Shame played a crucial role in predicting suicidal ideation, and the mediating effects of perceived burdensomeness and thwarted belongingness between shame and suicidal ideation were significant. Suicidal ideation is common among undergraduate students in China and merits greater attention. Shame, perceived burdensomeness, and thwarted belongingness may be important factors to assess among undergraduate students in suicide risk assessment and psychological intervention.

Testing the Strain Theory of Suicide – The Moderating Role of Social Support

Abstract. Background: According to the strain theory of suicide, strains, resulting from conflicting and competing pressures in an individual's life, are hypothesized to precede suicide. But social support is an important factor that can mitigate strains and lessen their input in suicidal behavior. Aims: This study was designed to assess the moderating role of social support in the relation between strain and suicidality. Methods: A sample of 1,051 employees were recruited in Beijing, the capital of China, through an online survey. Moderation analysis was performed using SPSS PROCESS Macro. Social support was measured with the Multidimensional Scale of Perceived Social Support, and strains were assessed with the Psychological Strains Scale. Results: Psychological strains are a good predictor of suicidality, and social support, a basic need for each human being, moderates and decreases the effects of psychological strains on suicidality. Limitations: The cross-sectional survey limited the extent to which conclusions about causal relationships can be drawn. Furthermore, the results may not be generalized to the whole of China because of its diversity. Conclusion: Social support has a tendency to mitigate the effects of psychological strains on suicidality.

Meaning in life as a protective factor against suicidal tendencies in Chinese University students

BACKGROUND

A substantial increase in rates of suicide worldwide, especially among late adolescents and young adults, has been observed. It is important to identify specific risk and protective factors for suicide-related behaviors among late adolescents and young adults. Identifying specific factors across the masses, not only in the Western, but also in the Asian context, helps researchers develop empirically informed intervention methods for the management of protective and risk factors of suicide.

METHODS

In the current study, 2074 students (706 males), filled out the Meaning in Life Questionnaire, with subscales of Search for Meaning (MLQ-S) and Presence of Meaning (MLQ-P); the Future Disposition Inventory-24 (FDI-24), with subscales of Positive Focus (PF), Suicide Orientation (SO), and Negative Focus (NF); and the Beck Hopelessness Scale (BHS). These scales measure protective and risk factors that are linked to suicidal behaviors; while suicidal behaviors were measured by the Suicidal Behaviors Questionnaire-Revised (SBQ-R). Mediation analyses were performed to test the models with both the MLQ-S and MLQ-P as the mediators between a) hopelessness, as measured by BHS and suicidal behaviors; and b) PF, SO, and NF, as measured by FDI-24, and suicidal behaviors.

RESULTS

We found that only MLQ-P mediated the relation between hopelessness and suicidal behaviors; while both MLQ-P and MLQ-S mediated PF, SO, and NF (as measured by FDI-24), and suicidal behaviors, respectively.

CONCLUSION

Meaning in life, including both the presence of meaning in life and search for meaning, can be good protective factors against suicidal behaviors.

Coping Strategies and Suicidality: A Cross-Sectional Study From China

Background and Objective: Suicide is a leading cause of death in young people. Suicidal thoughts and behaviors can be triggered by life and study stresses; therefore, it is important to understand the role of coping strategies. The current study analyzed the link between different coping strategies and suicidality in university students in China. Methods: A cross-sectional study of 2,074 undergraduate students from China used a stratified-clustered-random sampling method (response rate 94.4%). The Suicidal Behaviors Questionnaire-Revised Scale was used to identify suicidal risks, while the Brief COPE scale was used to measure different coping strategies. Univariate and multivariate logistic regression analyses were utilized to examine coping strategies and suicidality. Results: A negative association of some coping skills (active coping and positive reframing) with suicidality and a positive association of some other coping skills (self-distraction, substance abuse, behavioral disengagement, venting, and self-blame) with suicidality were observed after adjusting for sociodemographic and mental health variables. Conclusions: Training and supporting young people to identify and apply adaptive coping strategies to deal with life stress could help to reduce suicidal ideation and behavior.

The association between psychological strain and suicidal behaviors among college students: A mental health survey in Jilin Province, Northeast China

BACKGROUND

Suicide is a major global mental health problem among college students. The aim of the current study was to explore the association between the psychological strains of the strain theory of suicide and suicidal behaviors among college students.

METHODS

Participants comprised 1912 college students (16-28 years old, 47.2% female) from three universities in Jilin Province, China, who completed the self-report assessments of psychological strains (40 items Psychological Strains Scale) and suicidal behaviors (Suicidal Behaviors Questionnaire-Revised). The demographic characteristics included four variables: health status, psychological status, academic status and economic status.

RESULTS

Approximately 15.0% (286/1912) of participants were classified as having suicide risk, based on the cut-off scores of the SBQ-R. The prevalence of suicidal behaviors among males and females was 11.9% (120/1009) and 18.4% (166/903), respectively. Value strain (OR = 1.075, 95%CI: 1.057-1.094), aspiration strain (OR = 1.082, 95%CI: 1.064-1.101), deprivation strain (OR = 1.073, 95%CI: 1.052-1.093), and coping strain (OR = 1.095, 95%CI: 1.075-1.116) were risk factors for suicidality in college students. Coping strain (OR = 1.050, 95%CI: 1.023-1.077) was still positively associated with suicide risk in multivariate logistic regression. Logistic regression analysis indicated that coping strain had the highest correlation with suicidal behaviors.

LIMITATIONS

The directionality of the relationships cannot be deduced because this study is cross-sectional.

CONCLUSION

This study confirms a strong association between psychological strains and suicidal behaviors in college students. Some measures can be taken to reduce psychological strains to mitigate suicide risk among college students. More studies investigating coping strain among college students are warranted.

The future disposition Inventory-24: reliability and validity estimates in a large sample of Chinese University students

BACKGROUND

This study was designed to assess the factor structure, internal consistency reliability, and preliminary psychometric properties of the Chinese version of the Future Disposition Inventory-24 (FDI-24) in a large sample of Chinese university students.

METHODS

We translated the English version of the Future Disposition Inventory-24 (FDI-24) into Chinese and examined its factor structure, estimates of internal consistency reliability, and psychometric properties in a representative sample of university students. In particular, students (N = 2,074) from two universities in Shandong Province in China were identified using the multi-stage stratified sampling method. In addition to the FDI-24, we collected preliminary data using self-report instruments that included the Beck Hopelessness Scale (BHS) and a general sociodemographic information questionnaire.

RESULTS

The results of the internal consistency reliability estimates were adequate regarding the scores on the three FDI-24 subscales: Cronbach's alpha = .89-.97, Omega total = .85-.96, Revelle's Omega total = .88-.96, the greatest lower bound (GLB) = .89-.96 and Coefficient H = .86-.94. Bivariate correlation analyses showed evidence for criterion and discriminant validity. The 3-factor oblique-Geomin-rotation solution accounted for 62.92% of the total variance in the exploratory factor analysis (EFA). The exploratory structural equation modeling (ESEM) result showed that the 3-factor model provided adequate fit statistics for the sample data: the robust comparative fit index (R-CFI) was .959, robust Tucker Lewis index (R-TLI) was .946 and robust root mean square error of approximation (R-RMSEA) was .090.

CONCLUSION

The FDI-24 has a satisfactory factor structure, reliability estimates, and satisfactory evidence of concurrent validity estimates for students with different demographic and cultural backgrounds. The FDI-24 holds promise for use in future investigations with Chinese students.

UASB reactor for domestic wastewater treatment at low temperatures: a comparison between a classical UASB and hybrid UASB-filter reactor

The performance of an upflow anaerobic sludge blanket (UASB) reactor and a hybrid UASB-filter reactor was investigated and compared for the treatment of domestic wastewater at different operational temperatures (28, 20, 14 and 10 degrees C) and loading rates. For each temperature studied a constant CODt removal was observed as long as the upflow velocity was lower than 0.35 m/h. At these upflow velocities similar removals were observed for both reactor types at 28 and 20 degrees C, 82 and 72% respectively. However, at 14 and 10 degrees C the UASB reactor showed a better COD removal (70% and 48%, respectively) than the hybrid reactor (60% and 38%). COD removal resulted from biological degradation and solids accumulation in the reactors. At 28 degrees C, a constant 200 g sludge mass was observed in both reactors and COD removal was attributed to biological degradation only. At lower temperatures, solids accumulation was observed in addition to biological degradation with an increase in reactor sludge as the temperature decreased. The decrease in biological degradation at lower temperatures was offset by solids accumulation and explains the similar overall COD removal efficiency observed at 28 degrees C, 20 degrees C and 14 degrees C. The decrease in temperature was also followed by an increase in the effluent TSS concentration in both reactors. At 14 and 10 degrees C a lower effluent TSS concentration and better performance was observed in the UASB reactor.

Temperature effect on UASB reactor operation for domestic wastewater treatment in temperate climate regions

The performance of an upflow anaerobic sludge blanket (UASB) reactor was investigated for the treatment of domestic wastewater at different operational temperatures (28, 20, 14 and 10 degrees C) and loading rates. For each temperature studied a constant COD(t) removal was observed as long as the upflow velocity was lower than 0.35 m/h: 82% at 28 degrees C, 68% at 14 degrees C and 44% at 10 degrees C. At 20 degrees C the COD removal increased with the HRT, reaching similar values as at 28 degrees C for long HRT. At upflow velocities higher than 0.35 m/h, a reduction in total COD removal was observed due to washout of influent TSS. At 28 degrees C, a constant 200 g sludge mass was observed and COD removal was attributed to biological degradation only. At lower temperatures, COD removal resulted from degradation and solids accumulation in the reactor. The increase in reactor sludge was greater as the temperature decreased and explains the similar overall COD removal efficiency at 28 degrees C, 20 degrees C and 14 degrees C. During the transition from winter to summer conditions (10 degrees C to 28 degrees C), methane production initially increased due to the degradation of accumulated solids. Afterwards, methane production gradually declined and an increase in COD removal was observed, indicating that the TSS accumulated during the winter was exhausted and influent degradation remained.

Transmural high energy phosphate distribution and response to alterations in workload in the normal canine myocardium as studied with spatially localized 31P NMR spectroscopy

Spatially localized phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy has been applied to the study of the normal canine myocardium to measure the relative content of high energy phosphates across the left ventricular wall. Transmural NMR data were acquired in five voxels spanning the wall of the left ventricle using the FLAX-ISIS technique. The validity of the FLAX-ISIS approach in acquiring localized spectra for transmural studies and in providing quantitative information from the localized spectra was examined rigorously by studies involving phantoms, intact rats, and the canine myocardium in vivo. The results indicated that (1) this technique yields spatially resolved spectra with partial overlap between adjacent voxels and virtually no overlap between every other voxel; (2) in the canine heart, signals from subepicardium, midwall, and subendocardium can be detected separately without cross contamination; and (3) relative metabolite contents within a voxel and among voxels can be quantitated. Transmural 31P NMR spectra were acquired with cardiac gating on 29 separate animals either at early systole or late diastole, and at three different workloads with the heart rate peak systolic pressure product (RPP) increasing from 6000 mmHg/min to 35,000 mmHg/min. The data revealed that in the normal canine myocardium, the creatine phosphate (CP) content and the CP/ATP ratio was significantly lower in the subendocardium than in the subepicardium. ATP levels were transmurally constant. Both the CP content and the CP/ATP ratio measured for each voxel remained unaltered in relation to either the phase of the cardiac cycle or approximately fourfold increase in workload. Free ADP levels calculated for each voxel showed that ADP was relatively higher in the subendocardium than the subepicardium, and in all transmural layers was higher than its apparent Km for oxidative phosphorylation. In this domain changes in ADP content with workload and MVO2 are not expected and were not observed.

Use of coronary arteriography in the preoperative management of patients undergoing urgent repair of the thoracic aorta

Noninvasive innovations have advanced the timing and precision of diagnosis of acute dissection or enlarging aortic aneurysm. However, the need to perform coronary arteriography prior to surgical repair in these patients remains a question for many clinicians. This retrospective 10-year (1978 to 1988) review examined data of 54 patients undergoing urgent surgical repair of thoracic aortic tear, aneurysm, or dissection in our institution. Results of coronary arteriography and clinical variables (history of coronary artery disease, electrocardiographic abnormalities, surgical procedures, and in-hospital mortality) were tabulated. Twenty-seven patients had type A aortic dissection and 27 patients had type B. Twenty-four patients had aortic dissection or tear (type A or B) due to motor vehicle trauma. In patients with type A, a history and/or electrocardiogram suggestive of coronary artery disease was present in 16, in whom cardiac catheterization was performed in five. None required coronary bypass surgery or died. In the 11 patients with no clinical history of coronary artery disease or electrocardiographic abnormalities, six had cardiac catheterization, none had coronary artery disease, two had coronary reimplantation, and six died. Only 1 of the 27 patients with type A dissection had a perioperative myocardial infarction (a patient with a clinical history of coronary artery disease who did not undergo cardiac catheterization). In patients undergoing type B aortic repair, 10 had a clinical history or electrocardiogram consistent with coronary artery disease but only one underwent cardiac catheterization and subsequent coronary artery bypass graft surgery for coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Improved method for transcatheter retrieval of intracoronary detached angioplasty guidewire segments

A transcatheter technique using a probing catheter and 0.014 wire to form a loop snare was used percutaneously to safely retrieve segments of retained guidewire fragments in mid- and distal coronary arteries in three patients.

Spectroscopic imaging and spatial localization using adiabatic pulses and applications to detect transmural metabolite distribution in the canine heart

Adiabatic pulses have been employed in spectroscopic imaging and relaxation rate measurements at 4.7 T to demonstrate the feasibility of obtaining spectroscopic data from the complete sensitive volume of a surface coil using the surface coil as a transmitter and receiver. With conventional B1 sensitive pulses, spectroscopic localization or imaging techniques, such as chemical-shift imaging, yield resonance intensities that are distorted severely as a function of space, and maximal signal is detected from a small region within the complete sensitive volume of the coil. With adiabatic pulses, however, this problem is eliminated completely. In addition, a new method of spatial localization is introduced. This method, referred to as FLAX-ISIS, is a derivative of longitudinally modulated Fourier series window and ISIS approaches and utilizes adiabatic inversion and excitation pulses. The method allows construction of localized spectra for multiple regions along the surface coil axis by postacquisition data manipulation of a single set of free induction decays. These techniques were applied to the study of the myocardium using an implanted surface coil in an instrumented closed-chest canine model and in an open-chest preparation. The results demonstrate that one-dimensional techniques are adequate for transmural detection of metabolites provided signal origin is restricted to a column perpendicular to the left ventricle wall.

Transmural metabolite distribution in regional myocardial ischemia as studied with 31P NMR

Phosphorus-31 nuclear magnetic resonance (31P NMR) has been applied to study the canine heart prior to and during regional myocardial ischemia induced by partial flow reduction in the left anterior descending coronary artery (LAD). NMR data were acquired in a transmural fashion by restricting the signal to a column perpendicular to the heart wall using B0 gradients and obtaining spectroscopic spatial resolution along the third dimension using the B1 gradient and adiabatic excitation. With this approach, transmural spectra were accumulated in five separate voxels spanning the wall of the left ventricle from the epicardium to the endocardium. In the normal canine myocardium the levels of high-energy phosphates CP and ATP were relatively constant throughout the left ventricular wall, with only minor evidence of free inorganic phosphate in any of the transmural voxels. However, during sustained partial occlusion of the LAD, significant regional differences between the epi- and the endocardium were noted. The data demonstrate the importance of studying cardiac bioenergetics with transmural differentiation.

Effect of developmental stage on arginase and urea production in the liver of rat

Arginase activity in the liver, brain, and testis of rats was examined during the different phases of life span. When expressed as specific activity (micromoles of L-arginine hydrolyzed per minute per gram of whole homogenate protein), the enzyme activity in the brain and testis decreased markedly during the early stage of life and stayed low during the remainder of the life span. On the other hand, the arginase in the liver showed a great dependency on the developmental phase of the animal, showing two distinct peaks: one during the early phase (20 days after birth) and the other at a later time (3 months of age). This pattern of change in the hepatic arginase activity closely coincided with the pattern of the rate of urea synthesis determined with liver slices and expressed in terms of micromoles of urea formed per hour per gram of tissue slice. In contrast to the above observations, however, curves obtained by plotting the total liver arginase or urea synthetic activity vs the developmental stage of rats showed no measurable discontinuity. Further studies revealed that the observed pattern of specific activity of hepatic arginase was, in part, due to the change in the relative concentration of arginase protein in the liver.

Enzymatic methyl esterification of Escherichia coli ribosomal proteins

Enzymatic methyl ester formation in Escherichia coli ribosomal proteins was observed. Alkali lability of the methylated proteins and derivatization of the methyl groups as methyl esters of 3,5-dinitrobenzoate indicate the presence of protein methyl esters. The esterification reaction occurs predominantly on the 30S ribosomal subunit, with protein S3 as the major esterified protein. When the purified 30S subunit was used as the methyl acceptor, protein S9 was also found to be esterified. The enzyme responsible for the esterification of free carboxyl groups in proteins, protein methylase II (S-adenosyl-L-methionine:protein carboxyl methyltransferase, EC 2.1.1.24), was identified in E. coli Q13. This enzyme is extremely unstable when compared with that from mammalian origin. By molecular sieve chromatography, E. coli protein methylase II showed multiple peaks, with a major broad peak around 120,000 daltons and several minor peaks in the lower-molecular-weight region. Rechromatography of the major enzyme peak showed activities in several fractions that are much lower in molecular weight. The substrate specificity of the E. coli enzyme is similar to that of the mammalian enzyme. The Km value for S-adenosyl-L-methionine is 1.96 X 10(-6) M, and S-adenosyl-L-homocysteine was found to be a competitive inhibitor, with a Ki value of 1.75 X 10(-6) M.