Changes in the demographic distribution of Chicago gun-homicide decedents: 2015-2021: A violent death surveillance cross-sectional study (Preprint)

BACKGROUND

Homicide is one of the 5 leading causes of death in the United States for persons aged 1 to 44 years. In 2019, 75% of US homicides were by gun. Chicago has a gun-homicide rate 4 times the national average, and 90% of all homicides are by gun. The public health approach to violence prevention calls for a 4-step process, beginning with defining and monitoring the problem. Insight into the characteristics of gun-homicide decedents can help frame next steps, including identifying risk and protective factors, developing prevention and intervention strategies, and scaling effective responses. Although much is known about gun homicide because it is a long-standing, entrenched public health problem, it is useful to monitor trends to update ongoing prevention efforts.

OBJECTIVE

This study aimed to use public health surveillance data and methods to describe changes in the race/ethnicity, sex, and age of Chicago gun-homicide decedents from 2015-2021, in the context of year-to-year variation and an overall increase in the city's gun-homicide rate.

METHODS

We calculated the distribution of gun-related homicide deaths by 6 race/ethnicity and sex groups (non-Hispanic Black female, non-Hispanic White female, Hispanic female, non-Hispanic Black male, non-Hispanic White male, and Hispanic male), age in years, and age by age group. We used counts, percentages, and rates per 100,000 persons to describe the distribution of deaths among these demographic groups. Comparisons of means and column proportions with tests of significance set at P≤.05 were used to describe changes in the distribution of gun-homicide decedents over time by race-ethnicity-sex and age groups. The comparison of mean age by race-ethnicity-sex group is done using 1-way ANOVA with significance set at P≤.05.

RESULTS

The distribution of gun-homicide decedents in Chicago by race/ethnicity and sex groups had been relatively stable from 2015 to 2021 with 2 notable exceptions: a more than doubling of the proportion of gun-homicide decedents who were non-Hispanic Black female (3.6% in 2015 to 8.2% in 2021) and an increase of 3.27 years in the mean age of gun-homicide decedents. The increase in mean age coincided with a decrease in the proportion of non-Hispanic Black male gun-homicide decedents between the ages of 15-19 and 20-24 years and, conversely, an increase in the proportion of non-Hispanic Black male gun-homicide decedents aged 25-34 years<strong>.</strong>.

CONCLUSIONS

The annual gun-homicide rate in Chicago had been increasing since 2015 with year-to-year variation. Continued monitoring of trends in the demographic makeup of gun-homicide decedents is necessary to provide the most relevant and timely information to help shape violence prevention efforts. We detected several changes that suggest a need for increased outreach and engagement marketed toward non-Hispanic Black female and non-Hispanic Black male individuals between the ages of 25-34 years.

Household economic impact of road traffic injury versus routine emergencies in a low-income country

INTRODUCTION

Road traffic injuries (RTIs) are increasing and have disproportionate impact on residents of low- and middle-income countries (LMICs) where 90% of deaths occur. RTIs are a leading cause of death for those aged 15 - 29 years with costs estimated to be up to 3% of GDP. Despite this fact, little primary research has been done on the household economic impact of these events.

METHODS

From July to October 2016, 860 consecutive emergency department patients were enrolled and followed up at 6-8 weeks to assess the household financial impacts of these emergency presentations. At follow-up, patients were queried regarding health status, lost wages or schooling, household costs incurred due to their injury or illness, and assets sold.

RESULTS

860 patients were enrolled and 675 patients (78%) completed follow-up surveys. Of those, 660 had a confirmed reason for visit - 303 (45%) road traffic injuries, 357 (53%) other emergency presentations (non-RTI) - encompassing medical presentations and other types of injury, and reason for visit was missing for 15 patients (2%). More than 90% of RTI patients were working or in school prior to their injury. In the economically productive ages (15-44 years) RTI predominated (70%) vs non-RTI (39%). RTI patients were more likely to report residual disability (78.2% RTI vs 68.1% non-RTI, p=0.004). All emergency patients reported difficulty paying for basic needs (food, housing and medical expenses). More than ⅓ of emergency patients reported having to sell assets in order to meet basic needs after their illness or injury. Despite similar hospital costs and fewer lost days of work for both patients and caregivers, the mean financial impact on households of RTI patients was 37% more than for non-RTI patients. These costs equalled between 6-16 weeks of income for patients based on their occupation type and median reported pre-hospitalization income.

DISCUSSION

Ugandan emergency care patients suffered significant personal and household economic hardship. In addition to the need for policy and infrastructural changes to improve road safety, these findings highlight the need for basic emergency care systems to secure economic gains in vulnerable households and prevent medical impoverishment of marginal communities.

SARS-CoV-2 Surveillance System in Canada: Longitudinal Trend Analysis

BACKGROUND

The COVID-19 global pandemic has disrupted structures and communities across the globe. Numerous regions of the world have had varying responses in their attempts to contain the spread of the virus. Factors such as public health policies, governance, and sociopolitical climate have led to differential levels of success at controlling the spread of SARS-CoV-2. Ultimately, a more advanced surveillance metric for COVID-19 transmission is necessary to help government systems and national leaders understand which responses have been effective and gauge where outbreaks occur.

OBJECTIVE

The goal of this study is to provide advanced COVID-19 surveillance metrics for Canada at the country, province, and territory level that account for shifts in the pandemic including speed, acceleration, jerk, and persistence. Enhanced surveillance identifies risks for explosive growth and regions that have controlled outbreaks successfully.

METHODS

Using a longitudinal trend analysis study design, we extracted 62 days of COVID-19 data from Canadian public health registries for 13 provinces and territories. We used an empirical difference equation to measure the daily number of cases in Canada as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel model that was estimated using the generalized method of moments approach by implementing the Arellano-Bond estimator in R.

RESULTS

We compare the week of February 7-13, 2021, with the week of February 14-20, 2021. Canada, as a whole, had a decrease in speed from 8.4 daily new cases per 100,000 population to 7.5 daily new cases per 100,000 population. The persistence of new cases during the week of February 14-20 reported 7.5 cases that are a result of COVID-19 transmissions 7 days earlier. The two most populous provinces of Ontario and Quebec both experienced decreases in speed from 7.9 and 11.5 daily new cases per 100,000 population for the week of February 7-13 to speeds of 6.9 and 9.3 for the week of February 14-20, respectively. Nunavut experienced a significant increase in speed during this time, from 3.3 daily new cases per 100,000 population to 10.9 daily new cases per 100,000 population.

CONCLUSIONS

Canada excelled at COVID-19 control early on in the pandemic, especially during the first COVID-19 shutdown. The second wave at the end of 2020 resulted in a resurgence of the outbreak, which has since been controlled. Enhanced surveillance identifies outbreaks and where there is the potential for explosive growth, which informs proactive health policy.

Surveillance of the Second Wave of COVID-19 in Europe: Longitudinal Trend Analyses

BACKGROUND

The COVID-19 pandemic has severely impacted Europe, resulting in a high caseload and deaths that varied by country. The second wave of the COVID-19 pandemic has breached the borders of Europe. Public health surveillance is necessary to inform policy and guide leaders.

OBJECTIVE

This study aimed to provide advanced surveillance metrics for COVID-19 transmission that account for weekly shifts in the pandemic, speed, acceleration, jerk, and persistence, to better understand countries at risk for explosive growth and those that are managing the pandemic effectively.

METHODS

We performed a longitudinal trend analysis and extracted 62 days of COVID-19 data from public health registries. We used an empirical difference equation to measure the daily number of cases in Europe as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel model that was estimated using the generalized method of moments approach by implementing the Arellano-Bond estimator in R.

RESULTS

New COVID-19 cases slightly decreased from 158,741 (week 1, January 4-10, 2021) to 152,064 (week 2, January 11-17, 2021), and cumulative cases increased from 22,507,271 (week 1) to 23,890,761 (week 2), with a weekly increase of 1,383,490 between January 10 and January 17. France, Germany, Italy, Spain, and the United Kingdom had the largest 7-day moving averages for new cases during week 1. During week 2, the 7-day moving average for France and Spain increased. From week 1 to week 2, the speed decreased (37.72 to 33.02 per 100,000), acceleration decreased (0.39 to -0.16 per 100,000), and jerk increased (-1.30 to 1.37 per 100,000).

CONCLUSIONS

The United Kingdom, Spain, and Portugal, in particular, are at risk for a rapid expansion in COVID-19 transmission. An examination of the European region suggests that there was a decrease in the COVID-19 caseload between January 4 and January 17, 2021. Unfortunately, the rates of jerk, which were negative for Europe at the beginning of the month, reversed course and became positive, despite decreases in speed and acceleration. Finally, the 7-day persistence rate was higher during week 2 than during week 1. These measures indicate that the second wave of the pandemic may be subsiding, but some countries remain at risk for new outbreaks and increased transmission in the absence of rapid policy responses.

Latin America and the Caribbean SARS-CoV-2 Surveillance: Longitudinal Trend Analysis

Background

The COVID-19 pandemic has placed unprecedented stress on economies, food systems, and health care resources in Latin America and the Caribbean (LAC). Existing surveillance provides a proxy of the COVID-19 caseload and mortalities; however, these measures make it difficult to identify the dynamics of the pandemic and places where outbreaks are likely to occur. Moreover, existing surveillance techniques have failed to measure the dynamics of the pandemic.

Objective

This study aimed to provide additional surveillance metrics for COVID-19 transmission to track changes in the speed, acceleration, jerk, and persistence in the transmission of the pandemic more accurately than existing metrics.

Methods

Through a longitudinal trend analysis, we extracted COVID-19 data over 45 days from public health registries. We used an empirical difference equation to monitor the daily number of cases in the LAC as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel model that was estimated using the generalized method of moments approach by implementing the Arellano–Bond estimator in R. COVID-19 transmission rates were tracked for the LAC between September 30 and October 6, 2020, and between October 7 and 13, 2020.

Results

The LAC saw a reduction in the speed, acceleration, and jerk for the week of October 13, 2020, compared to the week of October 6, 2020, accompanied by reductions in new cases and the 7-day moving average. For the week of October 6, 2020, Belize reported the highest acceleration and jerk, at 1.7 and 1.8, respectively, which is particularly concerning, given its high mortality rate. The Bahamas also had a high acceleration at 1.5. In total, 11 countries had a positive acceleration during the week of October 6, 2020, whereas only 6 countries had a positive acceleration for the week of October 13, 2020. The TAC displayed an overall positive trend, with a speed of 10.40, acceleration of 0.27, and jerk of –0.31, all of which decreased in the subsequent week to 9.04, –0.81, and –0.03, respectively.

Conclusions

Metrics such as new cases, cumulative cases, deaths, and 7-day moving averages provide a static view of the pandemic but fail to identify where and the speed at which SARS-CoV-2 infects new individuals, the rate of acceleration or deceleration of the pandemic, and weekly comparison of the rate of acceleration of the pandemic indicate impending explosive growth or control of the pandemic. Enhanced surveillance will inform policymakers and leaders in the LAC about COVID-19 outbreaks.

Impact of Firearm Surveillance on Gun Control Policy: Regression Discontinuity Analysis

BACKGROUND

Public mass shootings are a significant public health problem that require ongoing systematic surveillance to test and inform policies that combat gun injuries. Although there is widespread agreement that something needs to be done to stop public mass shootings, opinions on exactly which policies that entails vary, such as the prohibition of assault weapons and large-capacity magazines.

OBJECTIVE

The aim of this study was to determine if the Federal Assault Weapons Ban (FAWB) (1994-2004) reduced the number of public mass shootings while it was in place.

METHODS

We extracted public mass shooting surveillance data from the Violence Project that matched our inclusion criteria of 4 or more fatalities in a public space during a single event. We performed regression discontinuity analysis, taking advantage of the imposition of the FAWB, which included a prohibition on large-capacity magazines in addition to assault weapons. We estimated a regression model of the 5-year moving average number of public mass shootings per year for the period of 1966 to 2019 controlling for population growth and homicides in general, introduced regression discontinuities in the intercept and a time trend for years coincident with the federal legislation (ie, 1994-2004), and also allowed for a differential effect of the homicide rate during this period. We introduced a second set of trend and intercept discontinuities for post-FAWB years to capture the effects of termination of the policy. We used the regression results to predict what would have happened from 1995 to 2019 had there been no FAWB and also to project what would have happened from 2005 onward had it remained in place.

RESULTS

The FAWB resulted in a significant decrease in public mass shootings, number of gun deaths, and number of gun injuries. We estimate that the FAWB prevented 11 public mass shootings during the decade the ban was in place. A continuation of the FAWB would have prevented 30 public mass shootings that killed 339 people and injured an additional 1139 people.

CONCLUSIONS

This study demonstrates the utility of public health surveillance on gun violence. Surveillance informs policy on whether a ban on assault weapons and large-capacity magazines reduces public mass shootings. As society searches for effective policies to prevent the next mass shooting, we must consider the overwhelming evidence that bans on assault weapons and/or large-capacity magazines work.

SARS-CoV-2 Surveillance in the Middle East and North Africa: Longitudinal Trend Analysis

BACKGROUND

The COVID-19 pandemic has disrupted the lives of millions and forced countries to devise public health policies to reduce the pace of transmission. In the Middle East and North Africa (MENA), falling oil prices, disparities in wealth and public health infrastructure, and large refugee populations have significantly increased the disease burden of COVID-19. In light of these exacerbating factors, public health surveillance is particularly necessary to help leaders understand and implement effective disease control policies to reduce SARS-CoV-2 persistence and transmission.

OBJECTIVE

The goal of this study is to provide advanced surveillance metrics, in combination with traditional surveillance, for COVID-19 transmission that account for weekly shifts in the pandemic speed, acceleration, jerk, and persistence to better understand a country's risk for explosive growth and to better inform those who are managing the pandemic. Existing surveillance coupled with our dynamic metrics of transmission will inform health policy to control the COVID-19 pandemic until an effective vaccine is developed.

METHODS

Using a longitudinal trend analysis study design, we extracted 30 days of COVID-19 data from public health registries. We used an empirical difference equation to measure the daily number of cases in MENA as a function of the prior number of cases, the level of testing, and weekly shift variables based on a dynamic panel data model that was estimated using the generalized method of moments approach by implementing the Arellano-Bond estimator in R.

RESULTS

The regression Wald statistic was significant (χ²₅=859.5, P<.001). The Sargan test was not significant, failing to reject the validity of overidentifying restrictions (χ²₂₉₄=16, P=.99). Countries with the highest cumulative caseload of the novel coronavirus include Iran, Iraq, Saudi Arabia, and Israel with 530,380, 426,634, 342,202, and 303,109 cases, respectively. Many of the smaller countries in MENA have higher infection rates than those countries with the highest caseloads. Oman has 33.3 new infections per 100,000 population while Bahrain has 12.1, Libya has 14, and Lebanon has 14.6 per 100,000 people. In order of largest to smallest number of cumulative deaths since January 2020, Iran, Iraq, Egypt, and Saudi Arabia have 30,375, 10,254, 6120, and 5185, respectively. Israel, Bahrain, Lebanon, and Oman had the highest rates of COVID-19 persistence, which is the number of new infections statistically related to new infections in the prior week. Bahrain had positive speed, acceleration, and jerk, signaling the potential for explosive growth.

CONCLUSIONS

Static and dynamic public health surveillance metrics provide a more complete picture of pandemic progression across countries in MENA. Static measures capture data at a given point in time such as infection rates and death rates. By including speed, acceleration, jerk, and 7-day persistence, public health officials may design policies with an eye to the future. Iran, Iraq, Saudi Arabia, and Israel all demonstrated the highest rate of infections, acceleration, jerk, and 7-day persistence, prompting public health leaders to increase prevention efforts.

Information Loss in Harmonizing Granular Race and Ethnicity Data: Descriptive Study of Standards

BACKGROUND

Data standards for race and ethnicity have significant implications for health equity research.

OBJECTIVE

We aim to describe a challenge encountered when working with a multiple-race and ethnicity assessment in the Eastern Caribbean Health Outcomes Research Network (ECHORN), a research collaborative of Barbados, Puerto Rico, Trinidad and Tobago, and the US Virgin Islands.

METHODS

We examined the data standards guiding harmonization of race and ethnicity data for multiracial and multiethnic populations, using the Office of Management and Budget (OMB) Statistical Policy Directive No. 15.

RESULTS

Of 1211 participants in the ECHORN cohort study, 901 (74.40%) selected 1 racial category. Of those that selected 1 category, 13.0% (117/901) selected Caribbean; 6.4% (58/901), Puerto Rican or Boricua; and 13.5% (122/901), the mixed or multiracial category. A total of 17.84% (216/1211) of participants selected 2 or more categories, with 15.19% (184/1211) selecting 2 categories and 2.64% (32/1211) selecting 3 or more categories. With aggregation of ECHORN data into OMB categories, 27.91% (338/1211) of the participants can be placed in the "more than one race" category.

CONCLUSIONS

This analysis exposes the fundamental informatics challenges that current race and ethnicity data standards present to meaningful collection, organization, and dissemination of granular data about subgroup populations in diverse and marginalized communities. Current standards should reflect the science of measuring race and ethnicity and the need for multidisciplinary teams to improve evolving standards throughout the data life cycle.

Quality and Publication of Emergency Medicine Trials Registered in ClinicalTrials.gov

Introduction

Promoting emergency medicine (EM) clinical trials research remains a priority. To characterize the status of clinical EM research, this study assessed trial quality, funding source, and publication of EM clinical trials and compared EM and non-EM trials on these key metrics. We also examined the volume of EM trials and their subspecialty areas.

Methods

We abstracted data from ClinicalTrials.gov (February 2000 – September 2013) and used individual study National Clinical Trial numbers to identify published trials (January 2007 – September 2016). We used descriptive statistics and chi-square tests to examine study characteristics by EM and non-EM status, and Kaplan-Meier curves and log-rank tests to compare time to publication of completed EM and non-EM studies.

Results

We found 638 interventional EM trials and 59,512 non-EM interventional trials conducted in the United States between February 2000 and September 2013, registered on ClinicalTrials.gov. EM studies were significantly less likely than non-EM studies to be National Institutes of Health-funded or to evaluate a drug or biologic. However, EM studies had significantly larger sample sizes, and were significantly more likely to use randomization and blinding. Overall, 34.3% of EM and 26.0% of non-EM studies were published in peer-reviewed journals. By subspecialty, more EM trials concerned medical/surgical and psychiatric/neurological conditions than trauma.

Conclusion

Although EM studies were less likely to have received federal or industry funding, and the EM portfolio consisted of only 638 trials over the 14-year study period, the quality of EM trials surpassed that of non-EM trials, based on indices such as randomization and blinding. This novel finding bodes well for the future of clinical EM research, as does the higher proportion of published EM than non-EM trials. Our study also revealed that trauma studies were under-represented among EM studies. Periodic assessment of EM trials with the metrics used here could provide an informative and valuable longitudinal view of progress in clinical EM research.

VIDAS Enzyme-Linked Fluorescent Immunoassay for Detection of Salmonella in Foods: Collaborative Study

The VIDAS SLM method for detection of Salmonella was compared with the Bacteriological Analytical Manual (BAM)/AOAC culture method in a collaborative study. Twenty laboratories participated in the evaluation. Each laboratory tested one or more of 6 test products: milk chocolate, nonfat dry milk, dried whole egg, soy flour, ground black pepper, and ground raw turkey. No significant differences (P&lt; 0.05) were observed between the 2 methods. The 2 methods were in agreement for 99% of 1544 samples analyzed. Of the 20 samples out of agreement, 8 were VIDAS SLM positive and BAM/AOAC negative, and 12 were VIDAS SLM negative and BAM/AOAC positive. The VIDAS SLM method for detection of Salmonella in foods has been adopted first action by AOAC INTERNATIONAL.

TEMPO® TVC for the Enumeration of Aerobic Mesophilic Flora in Foods: Collaborative Study

The automated system for enumeration of total viable count (TVC) in foods, TEMPO® TVC, uses a dehydrated culture medium and an enumeration card containing 48 wells across 3 different dilutions for the automatic determination of the most probable number (MPN). The alternative method was compared in a multilaboratory collaborative study to AOAC Method 966.23 for determination of aerobic plate count for nondairy products and the Standard Methods for the Examination of Dairy Products (SMEDP) Standard Plate Count for dairy products. Five food types, raw ground beef, raw ground chicken, cooked whitefish fillets, bagged lettuce, and milk, were analyzed for TVC by 14 collaborating laboratories throughout the United States and Canada. Three lots of naturally contaminated food products representing a wide range of counts were tested for each of the 5 food types. The study demonstrated that the overall repeatability, reproducibility, and mean log counts of the TEMPO TVC method were statistically comparable to those of the 2 standard methods at the 5 level.

Evaluation of VIDAS® Salmonella (SLM) Immunoassay Method with Rappaport-Vassiliadis (RV) Medium for Detection of Salmonella in Foods: Collaborative Study

A collaborative study was conducted to compare the VIDAS Salmonella (SLM) with Rappaport-Vassiliadis (RV) method for detection of Salmonella in foods to the current standard method presented in the U.S. Food and Drug Administration's Bacteriological Analytical Manual (BAM) and the culture method presented in AOAC's Official Methods of Analysis. The VIDAS SLM with RV method uses tetrathionate broth in combination with RV medium in place of selenite cystine broth for selective enrichment, thereby eliminating the hazardous waste issue for laboratories. Twenty five laboratories participated in the evaluation, each testing one or more of 8 test products: nonfat dry milk, dried egg, soy flour, lactic casein, milk chocolate, raw ground pork, raw ground turkey, and raw peeled shrimp. Results of the study showed no significant differences in the numbers of confirmed positive samples with the VIDAS SLM with RV procedure and the BAM/AOAC culture procedure. The VIDAS SLM with RV method was effective for rapid detection of Salmonella in foods. It is recommended that AOAC INTERNATIONAL modify the VIDAS Salmonella SLM procedure to include the RV method.

Evaluation of VIDAS® Immuno-Concentration Salmonella/VIDAS Salmonella Immunoassay Method for Detection of Salmonella in Selected Foods: Collaborative Study

The VIDAS Immuno-concentration Salmonella (ICS)/VIDAS Salmonella (SLM) immunoassay method for the detection of Salmonella was compared to the Bacteriological Analytical Manual (BAM)/AOAC culture method in a collaborative study. Thirty-two laboratories participated in the evaluation. Each laboratory tested one or more of the 6 test products: milk chocolate, nonfat dry milk, dried whole egg, soy flour, ground black pepper, and ground raw turkey. The 2 methods were in agreement for 1266 of the 1440 samples. Of the 174 samples not in agreement, 69 were VIDAS ICS/SLM-positive and BAM/AOAC-negative and 105 were VIDAS ICS/SLM-negative and BAM/AOAC-positive.

Evaluation of VIDAS® Immuno-Concentration Salmonella Assay Plus Selective Plate Method (Hektoen Enteric, Bismuth Sulfite, Salmonella Identification) for Detection of Salmonella in Selected Foods: Collaborative Study

The VIDAS Immuno-concentration Salmonella (ICS) plus selective plate method (Hektoen enteric, bismuth sulfite, Salmonella identification) method for the detection of Salmonella was compared to the Bacteriological Analytical Manual (BAM)/AOAC culture method in a collaborative study. Thirty-two laboratories participated in the evaluation. Each laboratory tested one or more of the 6 test products: milk chocolate, nonfat dry milk, dried whole egg, soy flour, ground black pepper, and ground raw turkey. The 2 methods were in agreement for 1283 of the 1440 test samples. Of the 157 test samples not in agreement, 82 were VIDAS ICS plus selective plate-positive and BAM/AOAC-negative, and 75 were VIDAS ICS plus selective plate-negative and BAM/AOAC-positive.

Salmonella in Selected Foods by VIDAS® Immuno-Concentration Salmonella Plus Selective Plate Method (Hektoen Enteric, Xylose Lysine Desoxycholate, Bismuth Sulfite): Collaborative Study

The VIDAS Immuno-concentration Salmonella (ICS) plus selective plate method (Hektoen enteric, xylose lysine desoxycholate, bismuth sulfite) method for the detection of Salmonella was compared to the Bacteriological Analytical Manual (BAM)/AOAC culture method in a collaborative study. Thirty-two laboratories participated in the evaluation. Each laboratory tested one or more of the 6 test products: milk chocolate, nonfat dry milk, dried whole egg, soy flour, ground black pepper, and ground raw turkey. The 2 methods were in agreement for 1297 of the 1455 samples. Of the 158 samples not in agreement, 82 were VIDAS ICS plus selective plate-positive and BAM/AOAC-negative, and 76 were VIDAS ICS plus selective plate-negative and BAM/AOAC-positive.

Providers' Note-Writing Practices for Post-traumatic Stress Disorder at Five United States Veterans Affairs Facilities

The capacity of electronic health records (EHRs) to capture desired information depends on the practices of health care providers. These practices have not been well studied in relation to post-traumatic stress disorder (PTSD). This qualitative study investigated how providers write EHR notes on PTSD through 38 interviews with providers working at five Veterans Affairs (VA) hospitals across the United States of America. Two overarching themes were prominent in the results. Providers used progress notes primarily to remember and access details for direct patient care, but only rarely for care coordination. Providers infrequently recorded information not judged to directly contribute to improved care, sometimes deliberately omitting information perceived to jeopardize patients' access to, or quality of, care. Omitted information frequently included sexual or non-military trauma. Understanding providers' thought processes can help clinicians be aware of the limitations of EHR notes as a tool for learning the histories of new patients. Similarly, researchers relying on EHR data for PTSD research should be aware of likely areas of missing data.

Obesity as a form of malnutrition: over-nutrition on the Uganda "malnutrition" agenda

The objectives were to highlight the burden of overweight and obesity as an additional area of importance for the malnutrition agenda in Uganda and to provide evidence-based considerations for stakeholders involved. Introduction: Mirroring other Low- and Middle-Income Countries (LMICs), Uganda is experiencing a “double burden” of over-nutrition related issues - both obesity and overweight, and related non-communicable diseases (NCDs) alongside the under-nutrition that has long plagued the country. Despite the commonplace assumption that under-nutrition is the predominant form of malnutrition in Uganda, we explore recent literature that in fact, challenges this notion. While food insecurity has contributed to the under-nutrition problem, a lack of dietary diversity also has a demonstrated role in increasing over-nutrition. We cannot afford to ignore over-nutrition concomitant with stunting and wasting in the country. Increase in the burden of this less acknowledged form of malnutrition in Uganda is critical to investigate, and yet poorly understood. A move towards increased regionally targeted over-nutrition research, funding, government prioritization and advocacy is needed.

Avian influenza in Australia: a summary of 5 years of wild bird surveillance

BACKGROUND

Avian influenza viruses (AIVs) are found worldwide in numerous bird species, causing significant disease in gallinaceous poultry and occasionally other species. Surveillance of wild bird reservoirs provides an opportunity to add to the understanding of the epidemiology of AIVs.

METHODS

This study examined key findings from the National Avian Influenza Wild Bird Surveillance Program over a 5-year period (July 2007-June 2012), the main source of information on AIVs circulating in Australia.

RESULTS

The overall proportion of birds that tested positive for influenza A via PCR was 1.9 ± 0.1%, with evidence of widespread exposure of Australian wild birds to most low pathogenic avian influenza (LPAI) subtypes (H1-13, H16). LPAI H5 subtypes were found to be dominant and widespread during this 5-year period.

CONCLUSION

Given Australia's isolation, both geographically and ecologically, it is important for Australia not to assume that the epidemiology of AIV from other geographic regions applies here. Despite all previous highly pathogenic avian influenza outbreaks in Australian poultry being attributed to H7 subtypes, widespread detection of H5 subtypes in wild birds may represent an ongoing risk to the Australian poultry industry.

Biomedical informatics techniques for processing and analyzing web blogs of military service members

INTRODUCTION

Web logs ("blogs") have become a popular mechanism for people to express their daily thoughts, feelings, and emotions. Many of these expressions contain health care-related themes, both physical and mental, similar to information discussed during a clinical interview or medical consultation. Thus, some of the information contained in blogs might be important for health care research, especially in mental health where stress-related conditions may be difficult and expensive to diagnose and where early recognition is often key to successful treatment. In the field of biomedical informatics, techniques such as information retrieval (IR) and natural language processing (NLP) are often used to unlock information contained in free-text notes. These methods might assist the clinical research community to better understand feelings and emotions post deployment and the burden of symptoms of stress among US military service members.

METHODS

In total, 90 military blog posts describing deployment situations and 60 control posts of Operation Enduring Freedom/Operation Iraqi Freedom (OEF/OIF) were collected. After "stop" word exclusion and stemming, a "bag-of-words" representation and term weighting was performed, and the most relevant words were manually selected out of the high-weight words. A pilot ontology was created using Collaborative Protégé, a knowledge management application. The word lists and the ontology were then used within General Architecture for Text Engineering (GATE), an NLP framework, to create an automated pipeline for recognition and analysis of blogs related to combat exposure. An independent expert opinion was used to create a reference standard and evaluate the results of the GATE pipeline.

RESULTS

The 2 dimensions of combat exposure descriptors identified were: words dealing with physical exposure and the soldiers' emotional reactions to it. GATE pipeline was able to retrieve blog texts describing combat exposure with precision 0.9, recall 0.75, and F-score 0.82.

DISCUSSION

Natural language processing and automated information retrieval might potentially provide valuable tools for retrieving and analyzing military blog posts and uncovering military service members' emotions and experiences of combat exposure.

Elder Abuse in Long-Term Care: Types, Patterns, and Risk Factors

The authors investigated types and patterns of elder abuse by paid caregivers in long-term care and assessed the role of several risk factors for different abuses and for multiple abuse types. The results are based on a 2005 random-digit-dial survey of relatives of persons in long-term care. We computed occurrence rates and conditional occurrence rates for each of six abuse types: physical, caretaking, verbal, emotional, neglect, and material. Among older adults who have experienced at least one type of abuse, more than half (51.4%) have experienced another type of abuse. Physical functioning problems, activities of daily living limitations, and behavioral problems are significant risk factors for at least three types of abuse and are significant for multiple abuse types. The findings have implications for those monitoring the well-being of older adults in long-term care as well as those responsible for developing public health interventions.

Elder abuse and neglect in Latino families: an ecological and culturally relevant theoretical framework for clinical practice

There is a scarcity of theoretical frameworks capable of describing precursors and dynamics associated with elder abuse and neglect in Latino families. The present manuscript seeks to address this gap in the literature by presenting an integrative theoretical framework that fosters an ecological and cultural understanding of elder abuse and neglect among Latinos. The proposed model rests on the premise that Latino families caring for elder adults have the ability to adapt to the demands of aging only if they are supported by nurturing environments. The usefulness of the model is threefold. First, the proposed model describes elder abuse and neglect as multifactorial phenomena and identifies specific risk factors associated with the etiology and maintenance of elder abuse and neglect in Latino families. Second, the model provides clinical applications, including reflections about the therapists' need to extend their scope of practice beyond traditional family therapy interventions. A brief case study is presented that illustrates the clinical application of the model with a Latino family. Implications for future research are discussed.

Near absence of IL-15R-alpha T-cells in EBV-associated Hodgkin lymphoma patients

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Background: Epstein-Barr virus (EBV) (+) Hodgkin's lymphoma (HL) has been linked to acute infectious mononucleosis (AIM). EBV-associated AIM was recently reported (Sauce et al, Blood 2006, 108: 11) to be associated with a long lasting immunologic scar (near complete absence of IL-15 receptor alpha (IL-15Ra expression on T cells in peripheral blood mononuclear cells (PBMC)). We sought to confirm the scar observation and to determine whether such a scar might also be characteristic of EBV (+) HL patients. Methods: PBMCs from 5 donors with history of AIM (3 months to 4 years before), 10 EBV-seropositive donors without history of AIM, 10 EBV-seronegative donors, 22 HL patients with EBV (+) tumors and 29 HL patients with EBV (-) tumors were assayed to determine IL-15Ra expression on CD3/CD8+ cells using a FACScalibur flow cytometer. Results: IL-15Ra expression in healthy donors with history of AIM [mean: 2.9% (1.5–6.5%)] was much lower than in those without history of AIM [mean: 83% (65–98%)] (p = 0.001). Expression did not differ between healthy EBV-seropositive donors without history of AIM [mean: 82% (65–95%)] and healthy EBV-seronegative donors [mean: 89% (82–98%)] (p = 0.32). Expression was markedly different between EBV (-) HL [mean: 82% (72–99%)] and EBV (+) HL patients [mean: 3.2% (1.1–7.1%)] [p = 0.001, 95% CI(10.3–32.1)]. No difference was found when age, time blood was drawn (pre or post-treatment), disease stage and histological subtype were compared. This IL- 15Ra deficit was seen in patients before and more than one year after standard therapy. Conclusions: This study confirms the virtual absence of IL-15Ra expression in lymphocytes from patients with history of AIM. That observation is now extended to include patients with EBV (+) HL at presentation and in remission. Whether this deficit contributes to the pathogenesis of EBV (+) associated HL remains to be determined.

No significant financial relationships to disclose.

A dose-finding study of liposomal daunorubicin with CVP (COP-X) in advanced NHL

BACKGROUND

Standard therapy for lymphoma consists of a cyclophosphamide (C), doxorubicin, vincristine (V), and prednisone (P) (CHOP) combination regimen. Liposomal daunorubicin (DaunoXome) is an alternative to doxorubicin for patients with lymphoma because of its more favorable safety profile and potentially more selective uptake in lymphoma. The objectives of this study were to determine the maximum tolerated dose (MTD) of liposomal daunorubucin with CVP (COP-X) and the tolerability of the regimen in patients with indolent lymphoma.

PATIENTS AND METHODS

Patients with low-grade and intermediate-grade lymphoma having adequate cardiac, hepatic, and renal function were enrolled. Patients received C 750 mg/m2, V 1.4 mg/m2 (maximum 2.0 mg), and liposomal daunorubicin 50-100 mg/m2 i.v. on day 1 and P 100 mg p.o. on days 1-5. MTD was the liposomal daunorubicin dose associated with 20% dose-limiting toxicity (ANC < 500/mm3 for > 5 days or febrile neutropenia).

RESULTS

Twenty patients, median age 59 years, were treated. The liposomal daunorubicin MTD combined with CVP was 70-80 mg/m2, depending on patient population. No significant non-hematologic toxicity occurred. Response rate was 44% (2 complete and 5 partial responses).

CONCLUSIONS

A liposomal daunorubicin dose of 80 mg/m2 in the COP-X regimen was well tolerated with little nonhematologic toxicity.

Effect of Helicobacter pylori products and recombinant cytokines on gastrin release from cultured canine G cells

BACKGROUND & AIMS

The pathophysiology of hypergastrinemia in Helicobacter pylori infection is undefined, but the infected antrum shows a marked inflammatory response with local production of cytokines. Hypergastrinemia and inflammatory infiltrate clear with successful eradication. The aim of this study was to examine whether the cytokines tumor necrosis factor alpha or interleukin 8 (IL-8), which are produced in the gastric mucosa of patients with H. pylori-induced peptic disease or H. pylori products, can stimulate gastrin release from isolated cultured canine G cells.

METHODS

Canine G cells were isolated by collagenase digestion, enriched by centrifugal elutriation, incubated with cytokines, bacterial components, or both, and gastrin release was measured by radioimmunoassay.

RESULTS

IL-8 (1 and 10 nmol/L) stimulated gastrin release by 34% +/- 13% and 43% +/- 23% (P < 0.05) above basal, respectively. H. pylori sonicates, water extract preparations, and lipopolysaccharide had no stimulatory actions, but the sonicates from two of four strains potentiated the effects of IL-8, leading to maximal gastrin release of 230% +/- 130% and 232% +/- 33% above basal, respectively (P < 0.05).

CONCLUSIONS

IL-8 stimulated gastrin release from isolated G cells, and the effect was potentiated by H. pylori products. The interaction of cytokines and H. pylori may contribute to the hypergastrinemia seen in vivo.

Effect of transforming growth factor alpha and interleukin 8 on somatostatin release from canine fundic D cells

BACKGROUND & AIMS

Helicobacter pylori infection in patients who have peptic ulcer disease is associated with altered regulation of gastric secretion, hypergastrinemia, and diminished somatostatin expression in gastric mucosa. Tumor necrosis factor (TNF)-alpha and interleukin (IL)-8 are the predominant cytokines produced in the gastric mucosa of patients with H. pylori infection. The aim of this study was to examine whether IL-8 and TNF-alpha could regulate somatostatin release from isolated canine gastric D cells.

METHODS

Canine gastric D cells were isolated from fundic mucosa and enriched by centrifugal elutriation. Secretagogue-stimulated somatostatin release was measured by radioimmunoassay.

RESULTS

TNF-alpha dose dependently increased somatostatin release after 2 hours of treatment. The stimulatory effect of TNF-alpha was additive to that of epinephrine but was unaffected by a maximal concentration of cholecystokinin. IL-8 did not alter basal or secretagogue (cholecystokinin, epinephrine)-mediated somatostatin release. The stimulatory effect of TNF-alpha (10 ng/mL) was potentiated by the addition of IL-8 (1 nmol/L), inhibited by octreotide and staurosporine, but unaffected by indomethacin. Pretreatment of D cells with TNF-alpha (10 ng/mL) for 24 hours abolished the subsequent stimulatory effect of this cytokine and secretagogues on somatostatin release.

CONCLUSIONS

TNF-alpha was shown to regulate somatostatin release from cultured D cells in a divergent manner.

Intestinal intraepithelial lymphocytes influence the production of somatostatin

BACKGROUND

We have previously demonstrated that intestinal intraepithelial lymphocytes (iIELs) inhibit lymphocyte proliferation. Because somatostatin also prevents lymphocyte proliferation, we hypothesized that iIELs may influence production of somatostatin.

METHODS

Isolates of intestinal epithelium that were obtained from Brown Norway (BN) rats and contained an iIEL-enriched population (defined as CD45+) were incubated with irradiated Lewis splenocytes for allogeneic stimulation. BN rat splenocytes incubated with irradiated Lewis splenocytes served as a control. Supernatants were harvested after 4 days and assayed for somatostatin by using a radioimmunoassay.

RESULTS

The somatostatin level in the intestinal epithelium-conditioned supernatant was significantly higher than that of the control group (176 +/- 60 versus 10 +/- 2 fmol/ml; p < 0.05). Removal of the CD45+ cell subset resulted in a fifteenfold reduction in somatostatin levels. The CD45+ cell lysates had significantly higher levels of somatostatin than did CD45+ depleted cells (1304 +/- 531 versus 128 +/- 41 fmol/ml; p < 0.05).

CONCLUSIONS

The isolates of intestinal epithelium produced significant amounts of somatostatin. Removal of the CD45+ cells caused a significant loss of somatostatin production. Intracellular levels of somatostatin appeared to be highest in the CD45+ subpopulation. These data suggest that iIELs (that is, CD45+ cells) may have a significant influence on the production of somatostatin and may be a source of somatostatin production. Production of somatostatin by iIELs may help modulate immune responses in gut-associated lymphoid tissue.

Tumour necrosis factor alpha stimulates gastrin release from canine and human antral G cells: possible mechanism of the Helicobacter pylori-gastrin link

There is evidence that gastric Helicobacter pylori (Hp) infection promotes duodenal ulceration by releasing gastrin. We therefore asked how Hp releases gastrin. Tumour necrosis factor alpha (TNF-alpha) is up-regulated in Hp gastritis and stimulates hormone release from pituitary cells, so we tested its effect on primary cultures of canine antral G cells and human antral fragments. TNF-alpha pretreatment (100 ng mL-1) of canine G cells significantly increased both basal (by 89%: P < 0.01) and bombesin-stimulated (by 39% P < 0.05) gastrin release. A similar pattern of increase was seen following TNF-alpha (20 ng mL-1) pretreatment of human antral fragments: basal gastrin release was increased by 38% (P < 0.05) and bombesin-stimulated by 26% (P < 0.05). This effect persisted during immunoblockade with anti-somatostatin antibody S6. We propose that TNF-alpha provides the link between Hp infection and gastrin release and thus contributes to duodenal ulceration.

Analysis of flow and vascular resistance in a model of the circle of Willis

A very simple model of the flow in the circle of Willis is described in this paper. Disregarding pulsatility and vessel wall elasticity, fluxes in all segments of the circle of Willis and its afferent and efferent vessels are calculated by applying the Poiseuille-Hagen formula. Comparison with the fluxes calculated numerically from a more sophisticated mathematical model, including pulsatility, vessel wall elasticity and nonlinear effects, revealed only very slight differences. In short, fluxes in the afferent vessels and the segments of the circle of Willis are influenced by any change of resistance within the network, whereas the fluxes in the efferent segments are dominated by the efferent resistance distribution. However, a great advantage of the present simple model is that it offers the possibility of an analytical approach which yields both an easy sensitivity analysis of parameters and an insight into the mechanisms that govern the flow in a network like the circle of Willis. It can be concluded that these mechanisms are similar to the principles of the Wheatstone bridge, known from electrical circuit theory.

An instrument to measure coping responses in employed mothers: preliminary results

The purpose of this study was to develop a survey instrument to measure coping responses in working mothers. Coping responses were defined as efforts to prevent, avoid, or control emotional distress. Based on interviews, literature review, and a survey of existing instruments, items were developed to measure these three functions of coping behaviors. The instrument was distributed to 133 married mothers who worked at least 15 hours per week outside the home; response rate was 93%. Nine subscales to measure coping responses in working mothers were identified. Alpha reliability coefficients for the subscales range from .65-.90. Construct validity of the subscales was investigated by examining specified relationships between subscale scores and role strain measures. All but one of the subscales were significantly correlated in the predicted direction with at least one of the role strain measures. The final instrument, the Coping Responses Inventory (CRI), is comprised of 59 Likert format items from which nine subscale scores can be calculated. Some aspects of the reliability and validity of this instrument have been investigated, but confirmation of the findings await further study. Potential uses of the CRI are as an instrument in survey research and as an exploratory tool in counseling interventions with employed women with children.

The Lundia Pro 5 dialyzer, a polycarbonate membrane dialyzer

Results of acute and long-term test runs of the Lundia Pro 5 dialyzer are presented. It is concluded that it has worked as an effective and safe dialyzer during the test period. Thoughts on future dialyzer tests are put forward for consideration.

A mathematical model of the flow in the circle of Willis

A mathematical model of the flow in the circle of Willis has been designed and the effects of (a) the large anatomical variation of the communicating arteries and (b) physiological changes of the resistances of the vertebral arteries have been studied. The influence of the posterior perforating arteries on the flow in the posterior communicating arteries has been investigated as well, with special attention being paid to the possible occurrence of a 'dead point'. In the model, the influence of diameters of the communicating arteries on the flow in the afferent vessels and the segments of the circle turns out to be considerable, especially in the range of the anatomical variation of the diameters. Within this range flow reductions due to an increased resistance of the vertebral artery will be compensated for by the system. Assuming that the values and ratios of the peripheral resistances are within the physiological range, a dead point is not to be expected in the flow in the posterior communicating arteries.

Nucleotide sequence of the alpha ribosomal protein operon of Escherichia coli

In Escherichia coli some 19 transcription units encoding the 52 ribosomal proteins are scattered throughout the genome. One of the units, the alpha operon, encodes genes for the ribosomal proteins S13, S11, S4 and L17 as well as the alpha subunit of RNA polymerase. We report here the complete 3.0 kb nucleotide sequence of the alpha operon. In addition, we have determined by S1 nuclease mapping the site of transcription termination in this operon.

Requirement for the 3' flanking region of the bovine growth hormone gene for accurate polyadenylylation

We examined whether the sequence extending 3' to the polyadenylylation site of the bovine growth hormone gene contains any signal that affects the polyadenylylation of the growth hormone mRNA. For this purpose, cloned copies of this gene, each containing a different length of growth hormone-specific sequence 3' to the wild-type polyadenylylation site, were used to transfect COS-1 cells. The polyadenylylation site on the mRNAs produced from the exogenously added growth hormone genes were analyzed with an S1 nuclease mapping procedure. We found that a gene containing 84 base pairs of its own 3' flanking sequence is capable of producing an accurately polyadenylylated mRNA. On the other hand, genes containing only 1, 10, or 13 base pairs of 3' flanking sequence were principally polyadenylylated at discrete sites either upstream or downstream from the wild-type position. Using a computer program, we examined whether secondary structures on the primary growth hormone transcript correlated with the site where the mRNA is polyadenylylated.

The poorly coping COPD patient: a psychotherapeutic perspective

An etiology of maladaptive coping in Chronic Obstructive Pulmonary Disease is proposed and a model for psychotherapeutic intervention with poorly coping COPD patients is presented. Failure in mourning, manifested by a lack of shift in patient's expectations and goals leads to: 1) difficulty in accepting illness related feelings of loss; 2) chronic anxiety; 3) attribution of responsibility for feelings and behavior to external factors; and 4) poor compliance with medical regime. Recommendations for establishing a therapeutic alliance with the poorly coping patient are discussed. Psychotherapeutic intervention aims at: 1) facilitating acceptance of losses and restructuring of life goals; 2) interrupting the cycle of alienation and social withdrawal; and 3) increasing patient's control over affective arousal and respiratory functioning. Utilization of supportive individual psychotherapy, family or marital therapy, and specific behavioral techniques is discussed. Family or marital therapy is seen as the treatment of choice. The psychotherapeutic model proposed is useful in promoting more adaptive coping in the COPD patient.

Characterization of hybrid plasmids carrying individual ribosomal ribonucleic acid transcription units of Escherichia coli

We have screened the strains with ColE1 hybrid plasmids constructed by Clarke and Carbon (Cell 9:91-99, 1976) for the presence of ribosomal ribonucleic acid (rRNA) genes on the plasmids and identified 16 strains whose plasmids carry rRNA genes. The structures of these 16 plasmids were compared by heteroduplex analysis, and the plasmids were classified into six groups on the basis of their chromosomal origins. Homology with known transducing-phage deoxyribonucleic acids and genetic mapping have assigned locations on the Escherichia coli chromosome to three of the six groups. These are rrnB near rif at 88 min, rrnC near ilvE at 83 min, and rrnD near aroE at 71 min. A fourth group is probably rrnA at 85 min (T. Ikemura and M. Nomura, Cell, 11:779-793, 1977). We conclude that the minimum number of rRNA transcription units per haploid chromosomes is seven, that is, the six groups identified in this work plus a known operon (rrnE near metA at 89 min) that we failed to find among the hybrid plasmids. This heteroduplex analysis also suggests that there are only two kinds of rRNA operons with respect to their spacer region; three of the six rRNA operon groups studied here have one kind, whereas the remaining three have the other kind.

Neonatal ophthalmoplegia with microfibers: a reversible myopathy?

An infant born with marked hypotonia showed prompt regression of skeletal muscle weakness, but by 7 weeks of age had total external ophthalmoplegia. Biopsy of the gluteus muscle at 14 days showed marked variation in fiber size with a large proportion of very small fibers (less than 3 mu). By 10 months of age, biopsy of the vastus was virtually normal. The inferior oblique muscle was replaced by fibrous tissue containing a few remaining degenerating fibers. The child was normal at 2 years of age except for mild facial weakness and ophthalmoplegia. This syndrome may be the result of a reversible intrauterine process.

DNA-dependent in vitro synthesis of fibosomal proteins, protein elongation factors, and RNA polymerase subunit alpha: inhibition by ppGpp

We have previously shown that the synthesis of ribosomal proteins (r proteins) in E. coli cells is under stringent control (Dennis and Nomura, 1974). Since guanosine tetraphosphate (ppGpp) has been implicated in stringent control, we examined the effects of ppGpp on the in vitro synthesis of r proteins directed by DNA from transducing phage lambdafus3 and lambdarifd18. lambdafus3 carries genes for protein elongation factors EF-Tu and EF-G, and RNA polymerase subunit alpha, in addition to genes for approximately 27 r proteins. lambdarifd18 carries genes for EF-Tu, RNA polymerase subunits beta and beta1, and a set of rRNAs, in addition to genes for approximately five r proteins. We have shown that low concentrations of ppGpp (0.2-0.3 mM) specifically inhibit DNA-dependent r protein synthesis in this system, and that this inhibition takes place directly, rather than as a consequence of the inhibition of rRNA synthesis by ppGpp. In addition, we have also shown that ppGpp inhibits the synthesis of EF-G, EF-Tu, and RNA polymerase subunit alpha, as well as rRNAs.

[Ballistocardiography on a model of the human cardiovascular system]

The linear relationship between the initial acceleration of blood flow and the I-wave as well as the HI-jerk of the acceleration ballistocardiogram is shown by experiments with a physical model of the cardiovascular system.

Inhibition of bacteriophage PBS2 replication in Bacillus subtilis by phleomycin

Phleomycin is an effective inhibitor of the replication of Bacillus subtilis bacteriophage PBS2, whose DNA contains uracil instead of thymine. Phleomycin does not affect the induction of the known phage enzymes involved in deoxyribonucleotide metabolism. But phage DNA synthesis is severely inhibited by phleomycin, and late virion protein synthesis is eliminated. These effects appear to result from a phleomycin-induced degradation of the parental phage DNA. Similar inhibitory and degradative effects on DNA are seen in phleomyinc-treated, uninfected cells. This system is unaffected by the related antibiotic, bleomycin.

Thermophore Therapy and Experimental Studies

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