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Texas Business Review, July 1977
College Enrollment Shifts Anticipate Current Job Market; San Antonio: A Military, Trade and Service Center; The High Price of HousingBureau of Business Researc
Characterization and biodegradation of two technical mixtures of side-chain fluorinated acryl copolymers
Evaluation of the Baltimore Health Corps Pilot: An Economic and Public Health Response to the Coronavirus
The Baltimore Health Corps was a city-run pilot launched in June 2020 and concluding in December, 2021. The pilot simultaneously addressed two issues: the spread of COVID-19 and the resulting employment crisis faced by Baltimore residents.The Baltimore City Health Department and the Mayor's Office of Employment Development led the Baltimore Health Corps, drawing on their experiences with equitable recruitment and hiring practices, workforce-supporting activities and public health worker training. Together, they led a team of public and private partners that included the Baltimore Civic Fund, Baltimore Corps, HealthCare Access Maryland (HCAM), Jhpiego and the Mayor's Office of Performance and Innovation.The initiative tracked those who contracted the virus at the height of the pandemic and connected COVID-19-positive individuals with testing, resources and other assistance. In doing so, the Baltimore Health Corps also placed unemployed workers on a path to high-quality, lasting careers via temporary positions as community health workers with the Baltimore City Health Department and HealthCare Access Maryland (HCAM). The program hired from a pool of Baltimore residents who reflected the city's racial and ethnic demographics and were unemployed, underemployed or furloughed because of the pandemic. By September 2021, 336 health workers had received training and took on roles within either the Health Corps' contact tracing and outreach program or the care coordination and access program.While these health worker positions were intended to last just eight months, as the pandemic persisted, the jobs were extended thanks to funding from the American Rescue Plan Act. As of May 2022, 126 Baltimore Health Corps workers remain employed with either the health department or HCAM, while 119 former staff members have since moved on to other employment opportunities.This is the Final Report to follow the Early Lessons Report for the Baltimore Health Corps Pilot Study. Readers are encouraged to review the Early Lessons Report for a detailed description of the formation of the Pilot Study, the role of each partner, as well as findings from the first year of the Pilot Study
Examination of three candidate technologies for high-lift devices on an aircraft wing
A research programme was initiated to examine three candidate high-lift technologies, which would, if implemented, simplify the mechanical complexity of the multiple component trailing-edge devices traditionally employed on civil transport aircraft. Experimental studies were undertaken with the aim of examining each technology in terms of its potential to favourably influence boundary layer development and improve the aerodynamic characteristics of a high-lift configuration. Preliminary studies of triangular serrated geometries, at the trailing edge of a modified flat plate, highlighted that the ability of the serrations to favourably influence the flow field development over an aft positioned single slotted flap was critically dependent upon the flap lap/gap and deflection angle. Under the test conditions, the serrations were most effective at low flap deflection angles, particularly serrations with a length corresponding to 13% flap chord. Extending these studies to a representative high-lift configuration significantly limited the range of flap laps/gaps and deflection angles over which the serrations were favourable. Furthermore, oil flow visualisation provided evidence of wake structures emanating from serration vertices, corroborating earlier hypotheses and suggesting the flow mechanism by which serrations favourably influenced boundary layer development over the upper surface of the downstream flap. Experiments indicated that when optimised, blowing tangentially from a slot at the trailing edge of the main element over the upper surface of a flap within a three-element high-lift configuration, provided a highly effective means of preventing boundary layer separation and increasing lift. This was corroborated by oil flow visualisation and computational simulations. Maintaining the same momentum coefficient and blowing through discrete orifices at the trailing edge of the main element, proved highly favourable, heightening the increment in lift in comparison to the corresponding tangential slot blowing configuration. Hence, the mass flow rate could be reduced in comparison to the tangential slot blowing configuration, without compromising the aerodynamic performance.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
High Resolution Mass Spectrometry of Polyfluorinated Polyether-Based Formulation
High resolution mass spectrometry (HRMS) was successfully applied to elucidate the structure of a polyfluorinated polyether (PFPE)-based formulation. The mass spectrum generated from direct injection into the MS was examined by identifying the different repeating units manually and with the aid of an instrument data processor. Highly accurate mass spectral data enabled the calculation of higher-order mass defects. The different plots of MW and the nth-order mass defects (up to n = 3) could aid in assessing the structure of the different repeating units and estimating their absolute and relative number per molecule. The three major repeating units were -C2H4O-, -C2F4O-, and -CF2O-. Tandem MS was used to identify the end groups that appeared to be phosphates, as well as the possible distribution of the repeating units. Reversed-phase HPLC separated of the polymer molecules on the basis of number of nonpolar repeating units. The elucidated structure resembles the structure in the published manufacturer technical data. This analytical approach to the characterization of a PFPE-based formulation can serve as a guide in analyzing not just other PFPE-based formulations but also other fluorinated and non-fluorinated polymers. The information from MS is essential in studying the physico-chemical properties of PFPEs and can help in assessing the risks they pose to the environment and to human health
Interspecies comparison of metabolism of two novel prototype PFAS
As a result of proposed global restrictions and regulations on current-use per-and polyfluoroalkyl substances (PFAS), research on possible alternatives is highly required. In this study, phase I in vitro metabolism of two novel prototype PFAS in human and rat was investigated. These prototype chemicals are intended to be safer-by-design and expected to mineralize completely, and thus be less persistent in the environment compared to the PFAS available on the market. Following incubation with rat liver S9 (RL-S9) fractions, two main metabolites per initial substance were produced, namely an alcohol and a short-chain carboxylic acid. While with human liver S9 (HL-S9) fractions, only the short-chain carboxylic acid was detected. Beyond these major metabolites, two and five additional metabolites were identified at very low levels by non-targeted screening for the ether- and thioether-linked prototype chemicals, respectively. Overall, complete mineralization during the in vitro hepatic metabolism of these novel PFAS by HL-S9 and RL-S9 fractions was not observed. The reaction kinetics of the surfactants was determined by using the metabolite formation, rather than the substrate depletion approach. With rat liver enzymes, the formation rates of primary metabolite alcohols were at least two orders of magnitude higher than those of secondary metabolite carboxylic acids. When incubating with human liver enzymes, the formation rates of single metabolite carboxylic acids, were similar or smaller than those experienced in rat. It also indicates that the overall metabolic rate and clearance of surfactants are significantly higher in rat liver than in human liver. The maximum formation rate of the thioether congener exceeded 10-fold that of the ether in humans but were similar in rats. Overall, the results suggest that metabolism of the prototype chemicals followed a similar trend to those reported in studies of fluorotelomer alcohols.</p
Mind the Gap: Persistent and Mobile Organic Compounds—Water Contaminants That Slip Through
The discharge of persistent and mobile organic chemicals (PMOCs) into the aquatic environment is a threat to the quality of our water resources. PMOCs are highly polar (mobile in water) and can pass through wastewater treatment plants, subsurface environments and potentially also drinking water treatment processes. While a few such compounds are known, we infer that their number is actually much larger. This Feature highlights the issue of PMOCs from an environmental perspective and assesses the gaps that appear to exist in terms of analysis, monitoring, water treatment and regulation. On this basis we elaborate strategies on how to narrow these gaps with the intention to better protect our water resources
Efficient synthesis of novel benzo[b][1,8]naphthyridin-4(1H)-ones and pyrido[2,3-b]quinoxalin-4(1H)-ones from alkynones and primary amines
An efficient palladium-catalyzed cyclization of o-chlorohetaryl ynones with aliphatic and aromatic primary amines represents a simple access to a wide range of benzo[b][1,8]naphthyridin-4(1H)-one and pyrido[2,3-b]quinoxalin-4(1H)- one derivatives in good to excellent yields. © 2013 Elsevier Ltd. All rights reserved
Occurrence of emerging persistent and mobile organic contaminants in European water samples
This is the Author’s Accepted Manuscript of the following article: Schulze, S., Zahn, D., Montes, R., Rodil, R., Quintana, J., & Knepper, T. et al. (2019). Occurrence of emerging persistent and mobile organic contaminants in European water samples. Water Research, 153, 80-90. doi: 10.1016/j.watres.2019.01.008The release of persistent and mobile organic chemicals (PMOCs) into the aquatic environment puts the quality of water resources at risk. PMOCs are challenging to analyze in water samples, due to their high polarity. The aim of this study was to develop novel analytical methods for PMOCs and to investigate their occurrence in surface and groundwater samples. The target compounds were culled from a prioritized list of industrial chemicals that were modeled to be persistent, mobile, and emitted into the environment. Analytical screening methods based on mixed-mode liquid chromatography (LC), hydrophilic interaction LC, reversed phase LC, or supercritical fluid chromatography in combination with mass spectrometric detection were successfully developed for 57 target PMOCs and applied to 14 water samples from three European countries. A total of 43 PMOCs were detected in at least one sample, among them 23 PMOCs that have not been reported before to occur in environmental waters. The most prevalent of these novel PMOCs were methyl sulfate, 2-acrylamino-2-methylpropane sulfonate, benzyltrimethylammonium, benzyldimethylamine, trifluoromethanesulfonic acid, 6-methyl-1,3,5-triazine-diamine, and 1,3-di-o-tolylguanidine occurring in ≥50% of the samples at estimated concentrations in the low ng L−1 up to μg L−1 range. The approach of focused prioritization combined with sensitive target chemical analysis proved to be highly efficient in revealing a large suite of novel as well as scarcely investigated PMOCs in surface and groundwaterThis work has been funded by the German BMBF (02WU1347A/B) and the Spanish MINECO/AEI (JPIW2013-117) in the frame of the collaborative international consortium (WATERJPI2013 – PROMOTE) of the Water Challenges for a Changing World Joint Programming Initiative (Water JPI) Pilot Call. RM, RR and JBQ also acknowledge Galician Council of Culture, Education and Universities and FEDER/EDRF funding (ED431C2017/36)S
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