Grain Size and Texture of Cu2ZnSnS4 Thin Films Synthesized by Cosputtering Binary Sulfides and Annealing: Effects of Processing Conditions and Sodium

We investigate the synthesis of kesterite Cu2ZnSnS4 (CZTS) polycrystalline thin films using cosputtering from binary sulfide targets followed by annealing in sulfur vapor at 500 {\deg}C to 650 {\deg}C. The films are the kesterite CZTS phase as indicated by x-ray diffraction, Raman scattering, and optical absorption measurements. The films exhibit (112) fiber texture and preferred low-angle and Sigma3 grain boundary populations which have been demonstrated to reduce recombination in Cu(In,Ga)Se2 and CdTe films. The grain growth kinetics are investigated as functions of temperature and the addition of Na. Significantly, lateral grain sizes above 1 um are demonstrated for samples grown on Na-free glass,demonstrating the feasibility for CZTS growth on substrates other than soda lime glass

Sex-Ethnic Disparities in HIV-Related Hospitalization and Mortality in Florida

To determine the racial/ethnic-differences in characteristics of inpatients hospitalized for Human immunodeficiency virus (HIV) disease/illness by gender and the correlates of HIV-related mortality in Florida. A retrospective analyses of public use data from the Florida Agency for Health Care Administration (AHCA), 2001 was utilized. From the de-identified hospital discharge file, discharge records with primary diagnosis of HIV disease/illness using the International Classification of Diseases, Ninth Edition (ICD 9) code were included. There were 9,279 inpatient records with diagnoses of HIV disease or illness. However, 9,113 records that belonged to black, white, and Hispanic patients were included in the analyses. The differences between sex-race/ethnic groups were tested using the chi-square tests and general linear models. In addition, multivariable logistic regression models were fitted to evaluate the correlates of HIV-related mortality in Florida Hospitals. Of 9,113 records, 64%, 23%, and 13% of records belonged to blacks, whites, and Hispanics, respectively. The type of admission, discharge status, length of hospital stay, health insurance status and age differed in six sex-, race/ethnic-specific groups. HIV-related mortality was significantly correlated with insurance status, age, and length of hospital stay. Under- or uninsured patients were about 27% more likely to die than those patients who had commercial health insurance. Older individuals (> 40 years) and those who stayed in hospitals more than 6 days were at higher risks of death compared with their reference groups (≤ 40 years old and ≤ 6 days of hospital stay). The potential causes (severity of disease, co-infections, preventive care, socio-economic status, cultural norms and beliefs about HIV) of disparities between sex-, race/ethnic-groups of Florida should be further explored

Prevalence and Correlates of Sexual Risk Behaviors by Gender among Multi-Ethnic Adolescents

Risky sex and its related behaviors (initiation of sex, alcohol, and drugs, school performance, delinquency) among adolescents are known to vary between genders. However, such variations among multi-ethnic adolescents of Florida are relatively understudied. The purpose of the study was to assess the prevalence of sexual and its related behaviors and evaluate the probability of sexual risks between genders. This study utilized the state-specific High School Youth Risk Behavior Survey (YRBS) of 2003. Weighted frequencies and stratified analyses using Rao-Scott chi-square (χ 2) test and survey logistic regression models were utilized. Adjusted odds ratios and their corresponding confidence limits and Rao-Scott χ 2 statistics for significance testing of parameter estimates were presented. There were 2,025 females and 1,828 males (n=3,853). Over 50% of participants were Whites, with 24.1% Hispanics, 20.3% African Americans, and 4.4% other. More females (20.3%) reported nonuse of condom compared with males (17.8%). Prevalence of other sexual risks (multiple sex partners, injection drug use, and sex under the influence of alcohol) was more common in males. Common correlates of at least one sexual risk behavior included older age, grade level, and early sexual debut. Surprisingly, school performance, delinquent behaviors, and early initiation of alcohol or drugs were not significantly associated with risky sex in males or females. Underlying variation of risks between males and females should be explored further. Health professionals working with adolescent populations should consider collecting locally relevant epidemiologic, survey, and social systems data to assess gender-variations in behaviors. Moreover, health prevention/promotion programs should be designed with reference to specific gender, and other differences especially among ethnically diverse adolescent populations

Co-Morbidities of Emergency Department Patients Admitted with Essential Hypertension in Florida

Although essential hypertension (EHT) has been associated with other chronic conditions, few studies have focused on co-morbidities and symptoms among patients admitted in hospital emergency departments (ED). The purpose is to compare the characteristics, co-morbidities and symptoms between ED admitted patients with three types (unspecified, benign, malignant) of EHT in Florida. A public use ED data from the Florida Agency for Health Care Administration (ACHA) in 2005 was used. Records included those with primary diagnosis of three types of EHT based on the International Classification of Diseases, 9 th edition (ICD 9) code. Group comparisons were made using chi square tests and linear regression models. Of 34,625 records, 96.3%, 2.0%, and 1.7% of them had unspecified, benign and malignant EHT, respectively. Types of EHT varied significantly by race and ethnicity, age group, principal payer, and discharge status. The most common secondary diagnoses included diabetes, abnormal lipid metabolism and hypercholesterolemia, disorder of urethra and urinary tract, hypokalemia, and anemia. While diabetes without complications was the most common co-morbidity of unspecified (10.7%) and malignant (12.3%) hypertensive patients, abnormal lipid metabolism was the most common co-morbidity of benign (20.0%) hypertensive patients. About 15.7% of benign patients had diabetes without complications. The most frequent symptom in all three groups was headache. About 60% (malignant), 34.7% (unspecified), and 4.1% (benign) of patients’ chief reasons for admission were not related to their primary diagnosis. While co-morbidities were present in all three types of EHT, the frequencies of co-morbidities and the chief reason for ED visit differed by types. Variation in factors contributing to co-morbidities between three types of EHT should be further explored

Gender-ethnic differences in increased arterial pulse pressure among young adults

Arterial stiffness (AS) can be measured in a variety of invasive and noninvasive techniques. AS is most frequently seen among older adults as it is considered a sign of aging. Hence, AS studies are sparse among young adults of different ethnic backgrounds. A common, noninvasive, surrogate measure of AS is arterial pulse pressure (APP). The objective of this study was to assess if ethnic differences in APP exist among young adults. College students attending an urban university in Florida were examined cross-sectionally in 2002. Data were initially collected to assess the Coronary Heart Disease Risk Factors among tri-ethnic population. Students of both genders belonging to one of the three ethnic groups (Hispanic, Black not of Hispanic origin, or White not of Hispanic origin) were included in the study. Data collection was performed via several self-administered questionnaires (e.g. Food Frequency, Cardiac Risk Evaluation), measurements of blood pressure (BP), body composition via Bioelectrical Impedance Analysis (BIA), and blood lipid and homocysteine (Hcy) levels. APP is derived mathematically as the difference between systolic and diastolic blood pressure. There were a total of 300 subjects in the current analyses. Mean age (years) and standard deviation (SD) of the subjects was 20.89 ± 3.75. Gender and ethnic breakdown of the study sample were as follows: 150 subjects in each gender group and 100 subjects in each ethnic group. The mean (mmHg) difference between males (43.11 ± 6.13) and females (40.80±8.01) was statistically significant ( p < 0.05). However, ethnic differences were not significant with 41.75±7.65, 41.00±7.69 and 43.12±7.27 for Hispanic, Black not of Hispanic origin, and White not of Hispanic origin respectively. The public health implication derived from a better understanding of the etiologic role of arterial stiffness in cardiovascular disease would be considerable and would play an important role in the prevention of hypertension in later life

Prevalence of increased arterial pulse pressure among children and adolescents

Arterial pulse pressure (APP) is used as a noninvasive measurement of arterial stiffness (AS). Most AS studies were conducted in adult populations as it is often considered a phenomenon of aging. The objective of this study is to assess the longitudinal change in prevalence of AS among children and adolescents. The Minneapolis Children's Blood Pressure Study (MCBPS) is a prospective cohort study and the initial (1978) and multiple timed measurements of systolic blood pressure (SBP) and fourth phase diastolic blood pressure (DBP4) were made semiannually or annually. Visit 16 was completed in 1987. Black and white subjects who participated in all 16 visits were included in the analysis (n=487). APP, a surrogate measure of AS, is derived mathematically as the difference between SBP and DBP4. The level of 60 mmHg or higher of APP was defined as presence of AS. There were 218 females, 269 males, 114 blacks and 373 whites. The mean ages of children in visits 1 and 16 were 7.7 (SD=0.7) and 16.6 (SD=0.7) years, respectively. Similarly, the mean APP levels at these two visits were 36.3 (SD=12.0), and 43.6 (SD=11.5) mmHg, respectively. Prevalence of increased APP varied at each timed point. At the beginning of the study (1978), prevalence was 3.9%. In 1987, prevalence increased to 10.1%. Proportions of those with increased APP ranged from 3.3% to 21.4% during 8 years of follow-up. Our results indicate that AS, as defined by APP, exists even during childhood and adolescence. These results should be confirmed by using a more accurate measure of AS that can be used in population studies