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1.
Article in English | MEDLINE | ID: mdl-37991254

ABSTRACT

PURPOSE: Despite recent advancements in policies supporting pregnancy and parenting-related resources for physician assistant (PA) students, there remains a paucity of data on the perceptions of family planning or available resources during training. The purpose of this study was to explore the perceptions of support for, and impact on, family planning and parenting, including lactation, among PA students. METHODS: This cross-sectional study used data collected from the American Academy of Physician Associates Student Survey between January and March 2023. Descriptive and inferential statistics were performed. RESULTS: A total of 557 students (557/1353; 41.2%) completed the survey. Less than 15% of students (14.4%) believed their program provides resources to support parental leave, and many students (52.1%) remained unsure whether resources exist(ed). There was a significant difference for PA students (P = .005) by gender in whether family planning affected the decision to pursue PA training over another profession, with female students proportionately affected more than male students. Medical school was the most often considered aside from PA training. Most PA students (311/548; 56.8%) also felt pressure to wait until after training to have children. In addition, multiple students (26/554; 4.7%) admitted to being asked questions they believed were biased or inappropriate regarding pregnancy or parenting during the interview process for, or after beginning, PA school. CONCLUSION: Programs should seek opportunities to support students through all stages of family planning. Support will require both cultural and structural shifts beginning with peer stigma and extending through admissions interview question audits, faculty training, university policies, and accreditation requirements.

2.
Sci Total Environ ; 747: 141281, 2020 Dec 10.
Article in English | MEDLINE | ID: mdl-32795797

ABSTRACT

Strategies to mitigate watershed nitrogen export are critical in managing water resources. Green infrastructure (GI) has shown the ability to remove nitrogen from stormwater, but the removal mechanism is unclear. Denitrification removes nitrate from water permanently, making it the most desirable removal mechanism. The year-round field performance of a roadside infiltration GI practice (bioretention) in Northern Virginia was monitored to investigate the transport of nitrogen and the occurrence and contribution of denitrification. Stormwater runoff volumes, nitrogen concentrations, and nitrate isotope ratios (δ15N-NO3- and δ18O-NO3-) were measured at the inlet and outlet of the bioretention during 24 storm events over 14 months. Nitrate concentration reductions (inlet vs. outlet) displayed seasonal trends, with higher reductions happening during warmer events and lower reductions or increases occurring during colder events. Cumulative bioretention nitrate and total dissolved nitrogen load reductions were 73% and 70%, respectively. Two out of 24 monitored events displayed denitrification isotope trends, indicating that although bioretention has denitrification potential, it is infrequent and other nitrogen removal mechanisms (i.e. infiltration and plant uptake) are primarily responsible for nitrogen surface effluent reductions. Only approximately 1.4% of the total reduced nitrate surface effluent load over the monitoring period was attributable to denitrification. Denitrification occurred during two of the largest monitored events, suggesting increased hydraulic retention time (HRT) promotes denitrification. Future GI designs should consider increasing HRT to encourage the important ecosystem service denitrification provides.


Subject(s)
Denitrification , Rain , Ecosystem , Isotopes , Nitrates , Nitrogen/analysis , Nitrogen Isotopes , Virginia
3.
Sci Total Environ ; 729: 138736, 2020 Aug 10.
Article in English | MEDLINE | ID: mdl-32361433

ABSTRACT

Winter deicing salt application has led to water quality impairment as stormwater carries salt ions (Na+ and Cl-) through watersheds. Green infrastructure (GI) is a promising urban stormwater management practice, but its efficacy in managing salt is unknown. GI is not yet designed to remove salt, but may have potential to mitigate its loading to surface waters. Two roadside infiltration-based GI practices in Northern Virginia (bioretention and bioswale) were monitored year-round over 28 precipitation events to investigate the transport of salt through modern stormwater infrastructure. Stormwater runoff volumes and concentrations of salt ions entering and exiting each GI were monitored to determine reductions of salt ions. Both the bioretention and bioswale significantly reduced effluent surface loads of Cl- and Na+ (76% to 82%), displaying ability to temporarily retain and infiltrate salts and delay their release to surface waters. Changes in bioretention soil chemistry revealed a small percentage of Na+ was stored long-term by ion exchange, but no long-term Cl- storage was observed. Limited soil storage along with groundwater observations suggest the majority of salt removed from stormwater by the bioretention infiltrates into groundwater. Infiltration GI can buffer surface waters from salt, but are also an avenue for groundwater salt loading.


Subject(s)
Groundwater , Rain , Sodium Chloride , Soil , Virginia , Water Movements , Water Quality
4.
J Chromatogr A ; 1587: 129-135, 2019 Feb 22.
Article in English | MEDLINE | ID: mdl-30591245

ABSTRACT

Nucleotides are among the most frequently used chemical building blocks in the research, development and manufacture of drug substances. They are composed of three highly polar subunit molecules (a nucleobase, a sugar, and at least one phosphate group), which makes their separation and analysis very challenging by conventional liquid chromatography techniques. Herein, we describe a simple, efficient, and cost-effective ion-exchange chromatography (IEC) method for the separation and purification of over 20 nucleotides. This method combines the use of a Tosoh TSKgel SuperQ-5P W resin in conjunction with a fully aqueous eluent profile (ammonium bicarbonate-based) that allows for a straightforward scale-up transition and convenient drying process with minimal environmental impact. This generic method was optimized using chromatography simulation software (ACD Labs/LC Simulator) and successfully applied to the preparative purification of multicomponent nucleotide mixtures using readily available Fast Protein Liquid Chromatography (FPLC) instrumentation. These IEC method conditions can be effectively applied as the starting point for method development and isolation of other highly polar nucleotide species beyond those investigated in this study.


Subject(s)
Chromatography, Ion Exchange/methods , Nucleotides/isolation & purification , Pharmaceutical Preparations/analysis , Anions , Chromatography, High Pressure Liquid , Chromatography, Reverse-Phase , Nucleotides/chemistry
5.
Chirality ; 19(9): 693-700, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17354260

ABSTRACT

The modern use of preparative chromatography in pharmaceutical development is illustrated by the case of a recent preclinical candidate from these laboratories. The synthesis of the candidate employed a coupling of two enantiopure intermediates, each of which could be resolved using preparative chiral chromatography. SFC screening was employed to identify the enantioselective stationary phases, and semipreparative SFC methods derived from this screening were used to produce gram amounts of enantiopure intermediate for initial studies. However, initial larger scale resolution required the translation of the SFC methods to HPLC conditions. Preparative chiral HPLC on a 30-cm i.d. column was then used to produce enantiopure intermediates which were coupled to give 170 g of the preclinical candidate. Subsequent preparation of the candidate at larger scale for later-stage clinical evaluation employed an improved synthesis in which one component was constructed by asymmetric synthesis. Resolution of the other component, now a more advanced intermediate, was carried out using newly obtained large-scale SFC equipment. Some discussion is presented on the varying strategies whereby preparative chiral chromatography can be used to support either short-term or long-term synthetic goals in preclinical pharmaceutical development.


Subject(s)
Chemistry, Pharmaceutical/methods , Chromatography/methods , Drug Evaluation, Preclinical/methods , Chromatography, High Pressure Liquid/methods , Chromatography, Liquid/methods , Drug Design , Models, Chemical , Pharmaceutical Preparations/chemistry , Stereoisomerism , Technology, Pharmaceutical/methods , Time Factors
6.
Org Biomol Chem ; 2(2): 168-74, 2004 Jan 21.
Article in English | MEDLINE | ID: mdl-14737638

ABSTRACT

A facile preparation of enantiopure ethyl (1S,5S,6S)-6-fluoro-2-oxobicyclo[3.1.0]hexane-6-carboxylate is described. The key feature of the synthesis involves copper-catalyzed enantioselective intramolecular cyclopropanation of a diazoketone to form endo-fluorocyclopropane in a single operation. Removal of a problematic chloroketone impurity using a reactive resin treatment enabled a high throughput enantiopurity upgrade by chiral HPLC. The development of a scalable synthesis of is presented, including details of the selection of catalyst and ligand optimization, incorporation of a reactive resin treatment and selection of chiral HPLC media and conditions.

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