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Per- and polyfluoroalkyl substances (PFAS) are organic chemicals with wide industrial and consumer uses. They are found ubiquitously at low levels in the environment and are detectable in humans and wildlife. Perfluorobutane Sulfonate (PFBS) is a short-chained PFAS used to replace perfluorooctane sulfonate in commerce. In general, the rate of clearance for the short-chained PFAS is faster than that for the long-chained congeners. This study evaluated the pharmacokinetic properties of PFBS and its hepatic transcriptional responses in CD-1 mice. Males and females were given PFBS by oral gavage at 30 or 300 mg/kg; controls received 0.5 % Tween-20 vehicle. Trunk blood was collected at 0.5, 1, 2, 4, 8, 16 and 24 h thereafter; liver and kidney were also harvested. Serum and tissue concentrations of PFBS were determined by HPLC-MS-MS. Expression of several hepatic nuclear receptor target genes was determined by qPCR. The half-life of PFBS was estimated as 5.8 h in the males and 4.5 h in the females. Tmax was reached within 1−2 h. Volume of distribution was similar between the two sexes (0.32−0.40 L/kg). The rate of PFBS clearance was linear with exposure doses. Within 24 h, serum PFBS declined to less than 5 % of Cmax. PFBS was detected in liver or kidney, although tissue levels of the chemical were only a fraction of those in serum. At 24 h after administration of 300 mg/kg PFBS, elevated expression of several hepatic genes targeted for PPARα, PPARy, and PXR but not by AhR, LXR or CAR was observed, with responses indistinguishable between males and females. Little to no transcriptional response was seen with the 30 mg/kg dose. The short serum half-lives of PFBS (4−5 h) in mice were comparable to those reported in rats. Although detection of PFBS in liver was low compared to that in serum even at the 300 mg/kg dose, the tissue level was sufficient to activate several hepatic nuclear receptors, which may represent an acute response to the chemical at a high dose.

Background: Congenital heart disease (CHD) is the leading cause of death within the first year of life because of birth defects. Complications related to respiratory infection caused by respiratory syncytial virus (RSV) increase risks in the CHD population. Prevention is key to minimizing risk, and administration of RSV prophylaxis, palivizumab, is recommended for infants with hemodynamically significant heart disease. Objective: Use the electronic medical record (EMR) to identify and ensure appropriate referral of CHD patients eligible for RSV prophylaxis. Design: Comparative, cross-sectional study design. Setting: Cardiac specialty clinic of a regional children’s hospital. Population: CHD patients younger than 24 months of age eligible for RSV prophylaxis. Intervention: Use the EMR to develop a method for identifying CHD patients eligible for RSV prophylaxis and implement a referral process. Results: Similar number of patients in the 2 RSV seasons studied. Rates of eligibility for RSV prophylaxis over the 2 seasons were the same. Improvements in documentation of eligibility by the provider from the first season to the second. Limitations: Inability to determine referral rates. Initial EMR search did not identify patients eligible for RSV prophylaxis. Inconsistent EMR data entry. Conclusions: Ongoing education on eligibility for RSV prophylaxis. Need for automated EMR referral. Ongoing evaluation of EMR systems identifying patients eligible for RSV prophylaxis.

The use of halogen donor additives in conventional high temperature (1500°C) copper vapour lasers (CVLs) has recently yielded significant enhancements in laser performance. Using a technique called ‘kinetic enhancement’ (KE), H2 and HCl buffer-gas additives have been found to increase the output power ~3× that observed for the same device operating with pure neon buffer-gas. For a 38mm bore CVL, it was shown that using H2-HCl-Ne gas mixtures increased output 1.5× and 1.3× that when using pure Ne and Ne with H2 additive respectively at the nominal CVL pulse repetition frequency (PRF) of 6 kHz. When increasing PRF, output increased linearly up to 22 kHz at which point the output power (150W) corresponded to 2.8× and 2.3× the maximum output power recorded for the tube when operated with either neon buffer-gas without or with hydrogen additive (53 W and 65 W respectively). In addition to the output power increases, the spatio-temporal characteristics of the KE-CVL

Kinetically enhanced copper vapour lasers (KE-CVLs) have performance characteristics far exceeding those of conventional (elemental copper) devices [1,2]. For example, a 38mm diameter CVL normally producing only 65W when employing H2-Ne buffer gas mixtures produces >150W when kinetically enhanced. In addition, to the greatly increased repetition rate scaling characteristics of KE-CVLs, spatio-temporal gain characteristics are much more favourable for the extraction of high beam quality output from these devices.

Over recent years we have shown that we can engineer the kinetics of conventional high-temperature CVLs using hydrogen additives, thereby improving their performance. In particular, we have shown that we can improve the spatio-temporal output characteristics of small- amd medium scale CVL systems, improving both their raw output power [1],[2] and high beam quality extraction [3].