Modeling breathing-zone concentrations of airborne contaminants generated during compressed air spray painting

This paper presents a mathematical model to predict breathing-zone concentrations of airborne contaminants generated during compressed air spray painting in cross-flow ventilated booths. The model focuses on characterizing the generation and transport of overspray mist. It extends previous work on conventional spray guns to include exposures generated by HVLP guns. Dimensional analysis and scale model wind-tunnel studies are employed using non-volatile oils, instead of paint, to produce empirical equations for estimating exposure to total mass. Results indicate that a dimensionless breathing zone concentration is a nonlinear function of the ratio of momentum flux of air from the spray gun to the momentum flux of air passing through the projected area of the worker's body. The orientation of the spraying operation within the booth is also very significant. The exposure model requires an estimate of the contaminant generation rate, which is approximated by a simple impactor model. The results represent an initial step in the construction of more realistic models capable of predicting exposure as a mathematical function of the governing parameters.     

不同深度糖尿病大鼠烫伤模型的制备

目的探讨恒温恒压电热烫伤仪制作糖尿病大鼠不同深度烫伤模型的可行性。方法链脲佐菌素诱导正常SD大鼠制作糖尿病大鼠模型，诱导成功1、2、3、4周检测皮肤晚期糖基化终产物、胶原含量，以正常SD大鼠作为对照，判断典型糖尿病性皮肤改变所需的时间。以恒温恒压烫伤仪制作烫伤模型，制模条件为0．5kg压力下，80℃，分别作用时间4．6、12s，48h后取材行苏木素-伊红（HE）染色检测烫伤深度。结果糖尿病大鼠诱导成功后4周，皮肤晚期糖基化终产物含量为（31．40±3．45）U／mg、胶原含量为（12．60±0．57）mg／g，与正常对照组比较差异有统计学意义（P〈0．05），并出现典型的糖尿病性皮肤改变。HE染色烫伤时间4、6、12s时深度依次为浅Ⅱ度、深Ⅱ度和Ⅲ度。结论恒温恒压电热烫伤仪制作糖尿病大鼠不同深度烫伤模型简单、方便，重复性高，为研究糖尿病创面愈合提供较为理想的模型。     

Gynaecological and Sexuality Profile of New Patients attending a Family Planning Clinic

2067 first-time attenders (70% of all new patients during the 9-month study period) at a Family Planning Association clinic in Victoria, Australia, completed a questionnaire aimed at obtaining data on the age at onset of sexual activity and contraceptive use patterns. The mean age of study respondents was 23 years; only 13% were married. 86% of the women reported a history of sexual intercourse. The average age at 1st intercourse was 17.4 years, and over 50% were sexually active before 18 years of age. 51% did not use contraception at the time of 1st intercourse, and this rate was lower (37%) among women aged 15 years or less at coitarche. Of those who had used contraception, the most common methods were condoms (52%) and oral contraceptives (37%). When asked to rate the quality of their 1st act of sexual intercourse, 12% indicated the experience was better than they expected, 50% said it was as good as expected, and 38% indicated it was worse than anticipated. 90% claimed that the quality of their sexual experiences has improved since the 1st time. In terms of current frequency of sexual intercourse, 60% reported sexual relations less than twice a week, 26% have sex 2-3 times a week, and 14% have intercourse more than 3 times a week. When asked about their recent contraceptive practice, 47% reported contraception is always used, 26% use contraception most of the time, 10% use contraception sometimes, 5% rarely use such methods, and 12% never use family planning. Since these subjects were either already sexually active or were planning to initiate sexual activity, they are not representative of Australia's female population as a whole. However, they are an important target for family planning education programs.     

Population-based trends in ambulatory surgery for urinary incontinence

Introduction and hypothesis

Surgical procedures for stress urinary incontinence (SUI) have become progressively less invasive and easier to perform with the development of new technologies such as the midurethral sling. For these reasons, it seems logical to conclude that midurethral slings would supplant other surgical treatments for incontinence. The purpose of this study was to assess the impact of this technology on trends in ambulatory surgery for incontinence over the past decade.

Methods

We searched Current Procedure Terminology codes and the State Ambulatory Surgery Database from 2001 through 2009 to identify all ambulatory procedures for incontinence. Next, we calculated age-adjusted rates separately for each procedure. We then fit a multilevel model to characterize patient and regional factors associated with the preferential use of midurethral slings over alternative treatments.

Results

Midurethral slings and submucosal injections comprised >90 % of all ambulatory procedures for SUI during the time period examined. Age-adjusted rates of midurethral slings increased dramatically, from 2.36 to 9.45/10,000 population (p?<?0.001), whereas rates of submucosal injections remained relatively stable, from 1.75 to 1.41/10,000 population (p?=?0.226). Not surprisingly, older ([odds ratio (OR) 0.61; 95 % confidence interval (CI) 0.56–0.66] and more infirm patients (OR 0.60; CI 0.44–0.83) were more likely to receive submucosal injection therapy than to receive midurethral slings.

Conclusions

Rates of midurethral slings have increased significantly by fourfold. Rates of submucosal injections, however, have remained fairly stable during this time period, suggesting that sling dissemination has led to an increase in rates of incontinence procedures as opposed to replacing old technologies in the ambulatory setting.     

Endotoxin promotes synergistic lethality during concurrent Escherichia coli and Candida albicans infection.

Previous studies have suggested that the lipopolysaccharide (LPS, endotoxin) component of the gram-negative bacterial cell wall is a key virulence factor that serves to enhance mortality during infections in which fungi and gram-negative bacteria are copathogens. To test this hypothesis, mice were challenged ip with Escherichia coli 0111:B4, Candida albicans, or both, and the effect of administration of anti-E. coli 0111:B4 LPS monoclonal antibody (mAb) 8G9 on endotoxemia, bacteremia, and mortality was assessed. E. coli (2 x 10(7) colony-forming units (CFU)) plus C. albicans (6 x 10(7) CFU) infection produced 100% mortality at 7 days, compared to the relatively low mortality caused by infection with either E. coli or C. albicans alone (20 and 3%, respectively, P less than 0.01). Administration of mAb 8G9 to animals receiving both pathogens reduced mortality (100% versus 14%, P less than 0.05), endotoxemia (3653 +/- 3187 versus 2 +/- 2 endotoxin units (EU), P less than 0.01), and bacteremia (4.2 +/- 2.3 versus 1.1 +/- 2.1 log(CFU/ml), P less than 0.01) compared to animals receiving saline alone. In a separate series of experiments, purified E. coli 0111:B4 LPS was administered in place of viable E. coli. The simultaneous injection of 200 micrograms E. coli LPS and C. albicans (6 x 10(7) CFU) produced 93% mortality at 7 days, compared to the low mortality that occurred following injection with either E. coli 0111:B4 LPS or C. albicans alone (21 and 3% respectively, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)     

Assessment of β-Cell Mass and α- and β-Cell Survival and Function by Arginine Stimulation in Human Autologous Islet Recipients

We used intravenous arginine with measurements of insulin, C-peptide, and glucagon to examine β-cell and α-cell survival and function in a group of 10 chronic pancreatitis recipients 1–8 years after total pancreatectomy and autoislet transplantation. Insulin and C-peptide responses correlated robustly with the number of islets transplanted (correlation coefficients range 0.81–0.91; P < 0.01–0.001). Since a wide range of islets were transplanted, we normalized the insulin and C-peptide responses to the number of islets transplanted in each recipient for comparison with responses in normal subjects. No significant differences were observed in terms of magnitude and timing of hormone release in the two groups. Three recipients had a portion of the autoislets placed within their peritoneal cavities, which appeared to be functioning normally up to 7 years posttransplant. Glucagon responses to arginine were normally timed and normally suppressed by intravenous glucose infusion. These findings indicate that arginine stimulation testing may be a means of assessing the numbers of native islets available in autologous islet transplant candidates and is a means of following posttransplant α- and β-cell function and survival.     

Combining 2 Commonly Adopted Nutrition Instruments in the Critical Care Setting Is Superior to Administering Either One Alone

Background: This study aimed to determine the agreement between the modified Nutrition Risk in Critically ill Score (mNUTRIC) and the Subjective Global Assessment (SGA) and compare their ability in discriminating and quantifying mortality risk independently and in combination. Methods: Between August 2015 and October 2016, all patients in a Singaporean hospital received the SGA within 48 hours of intensive care unit admission. Nutrition status was dichotomized into presence or absence of malnutrition. The mNUTRIC of patients was retrospectively calculated at the end of the study, and high mNUTRIC was defined as scores ≥5. Results: There were 439 patients and 67.9% had high mNUTRIC, whereas only 28% were malnourished. Hospital mortality was 29.6%, and none was lost to follow‐up. Although both tools had poor agreement (κ statistics: 0.13, P < .001), they had similar discriminative value for hospital mortality (C‐statistics [95% confidence interval (CI)], 0.66 [0.62–0.70] for high mNUTRIC and 0.61 [0.56–0.66] for malnutrition, P = .12). However, a high mNUTRIC was associated with higher adjusted odds for hospital mortality compared with malnutrition (adjusted odds ratio [95% CI], 5.32 [2.15–13.17], P < .001, and 4.27 [1.03–17.71], P = .046, respectively). Combination of both tools showed malnutrition and high mNUTRIC were associated with the highest adjusted odds for hospital mortality (14.43 [5.38–38.78], P < .001). Conclusion: The mNUTRIC and SGA had poor agreement. Although they individually provided a fair discriminative value for hospital mortality, the combination of these approaches is a better discriminator to quantify mortality risk.