The Optical Depth of H II Regions in the Magellanic Clouds

We exploit ionization-parameter mapping (IPM) as a powerful tool to measure the optical depth of star-forming H II regions. Our simulations using the photoionization code CLOUDY and our new, SURFBRIGHT surface-brightness simulator demonstrate that this technique can directly diagnose most density-bounded, optically thin nebulae using spatially resolved emission-line data. We apply this method to the Large and Small Magellanic Clouds (LMC and SMC), using the data from the Magellanic Clouds Emission Line Survey. We generate new H II region catalogs based on photoionization criteria set by the observed ionization structure in the [S II ]/[O III ] ratio and Hα surface brightness. The luminosity functions from these catalogs generally agree with those from Hα-only surveys. We then use IPM to crudely classify all the nebulae into optically thick versus optically thin categories, yielding fundamental new insights into Lyman-continuum (LyC) radiation transfer. We find that in both galaxies, the frequency of optically thin objects correlates with Hα luminosity, and that the numbers of these objects dominate above log L /(erg s –1 ) ≥ 37.0. The frequencies of optically thin objects are 40% and 33% in the LMC and SMC, respectively. Similarly, the frequency of optically thick regions correlates with H I column density, with optically thin objects dominating at the lowest N (H I ). The integrated escape luminosity of ionizing radiation is dominated by the largest regions and corresponds to luminosity-weighted, ionizing escape fractions from the H II region population of ≥0.42 and ≥0.40 in the LMC and SMC, respectively. These values correspond to global galactic escape fractions of 4% and 11%, respectively. This is sufficient to power the ionization rate of the observed diffuse ionized gas in both galaxies. Since our optical depth estimates tend to be underestimates, and also omit the contribution from field stars without nebulae, our results suggest the possibility of significant galactic escape fractions of LyC radiation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98568/1/0004-637X_755_1_40.pd

Current substance use in patients with gastric cancer in Southern Iran

Background: Psychiatric disorders may affect patients suffering from cancer and substance use disorders. Objective: This study was undertaken to evaluate the prevalence of tobacco and opioid use in patients with gastric cancer in Shiraz, Fars Province and Southern Iran. Materials and Methods: In a hospital survey of 177 gastric cancer patients aged 24 years and more, a semistructured-interview was performed based on SDM-IV criteria during the year 2003. Results: The mean age of the patients was 58.13 (SD=14.03) years. Among the subjects, 50.9% (90) were tobacco dependent (61.5% men and 29.4% women, P < 0.001), while 10 (5.7%) were opioid-dependent (7.3% men and 1.9% women, P =0.16). Tobacco and opioid-dependency were not significantly related to age groups, economical or occupational status. Mean ages of tobacco and opioid-dependants were not significantly different from nondependants. Conclusions: Tobacco and opioid dependency were common problems among gastric cancer patients. This report provides useful information for health planning. Men were at greater risk than women. Treatment programs should focus on all age-groups, all occupations and all income-levels

Epidemiology of depression among infertile and fertile couples in Shiraz, Southern Iran

BACKGROUND: Depression is considered as one of the main psychological disorders associated with infertility. Depression may play a significant role in the life of infertile individuals, their infertility treatment follow-up and in their hopefulness for the future; it may also influence the intensity and continuousness of the mutual relationship of the affected couple. AIMS: This study was done to determine the depression rate and make a comparison between infertile and fertile couples with respect to the same. SETTING AND DESIGN: The depression rate was evaluated between two groups - infertile couples (case group) and fertile couples (control group). MATERIALS AND METHODS: Ninety-one infertile couples (cases) and 9l fertile ones (controls) were randomly enrolled in our study. Beck depression inventory (BDI) and demographic information were provided. STATISTICAL ANALYSIS: We used Chi-square, t-test; and one-way Analysis of Variance (ANOVA) was performed to find out significant difference between infertility duration in various couples and its effect on the score of depression. RESULTS: The BDI mean difference between infertile and fertile couples was significant (P=0.015). It was significantly more among couples with infertility from 1-3 years′ duration compared to those with infertility of 1-year duration or less. CONCLUSION: Regarding the high rate of depression among infertile couples, it seems necessary to pay more attention to infertility centers that offer psychological and psychiatric services

Current substance use in patients with gastric cancer in Southern Iran

Background: Psychiatric disorders may affect patients suffering from cancer and substance use disorders. Objective: This study was undertaken to evaluate the prevalence of tobacco and opioid use in patients with gastric cancer in Shiraz, Fars Province and Southern Iran. Materials and Methods: In a hospital survey of 177 gastric cancer patients aged 24 years and more, a semistructured-interview was performed based on SDM-IV criteria during the year 2003. Results: The mean age of the patients was 58.13 (SD=14.03) years. Among the subjects, 50.9% (90) were tobacco dependent (61.5% men and 29.4% women, P &lt; 0.001), while 10 (5.7%) were opioid-dependent (7.3% men and 1.9% women, P =0.16). Tobacco and opioid-dependency were not significantly related to age groups, economical or occupational status. Mean ages of tobacco and opioid-dependants were not significantly different from nondependants. Conclusions: Tobacco and opioid dependency were common problems among gastric cancer patients. This report provides useful information for health planning. Men were at greater risk than women. Treatment programs should focus on all age-groups, all occupations and all income-levels