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The organic composition of coastal sea spray aerosol is important for both atmospheric chemistry and public health but remains poorly characterized. Coastal waters contain an organic material derived from both anthropogenic processes, such as wastewater discharge, and biological processes, including biological blooms. Here, we probe the chemical composition of the organic fraction of sea spray aerosol over the course of the 2019 SeaSCAPE mesocosm experiment, in which a phytoplankton bloom was facilitated in natural coastal water from La Jolla, California. We apply untargeted two-dimensional gas chromatography to characterize submicron nascent sea spray aerosol samples, reporting ∼750 unique organic species traced over a 19 day phytoplankton bloom experiment. Categorization and quantitative compositional analysis reveal three major findings. First, anthropogenic species made up 30% of total submicron nascent sea spray aerosol organic mass under the pre-bloom condition. Second, biological activity drove large changes within the aerosolized carbon pool, decreasing the anthropogenic mass fraction by 89% and increasing the biogenic and biologically transformed fraction by a factor of 5.6. Third, biogenic marine organics are underrepresented in mass spectral databases in comparison to marine organic pollutants, with more than twice as much biogenic aerosol mass attributable to unlisted compounds.

In the western United States, the number and severity of large wildfires have been growing for decades. Biomass burning (BB) is a major source of volatile organic compounds (VOCs) to the atmosphere both globally and regionally. Following emission, BB VOCs are oxidized while being transported downwind, producing ozone, secondary organic aerosols, and secondary hazardous VOCs. In this research, we measured VOCs using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) in an urban area 55-65 km downwind of the October 2017 Northern California wildfires. Nonaromatic oxygenated compounds were the dominant component of BB VOCs measured. In the smoke plumes, the VOCs account for 70-75% of the total observed organic carbon, with the remainder being particulate matter (with a diameter of2.5 μm, PM

Time spent in residences substantially contributes to human exposure to volatile organic compounds (VOCs). Such exposures have been difficult to study deeply, in part because VOC concentrations and indoor occupancy vary rapidly. Using a fast-response online mass spectrometer, we report time-resolved exposures from multi-season sampling of more than 200 VOCs in two California residences. Chemical-specific source apportionment revealed that time-averaged exposures for most VOCs were mainly attributable to continuous indoor emissions from buildings and their static contents. Also contributing to exposures were occupant-related activities, such as cooking, and outdoor-to-indoor transport. Health risk assessments are possible for a subset of observed VOCs. Acrolein, acetaldehyde, and acrylic acid concentrations were above chronic advisory health guidelines, whereas exposures for other assessable species were typically well below the guideline levels. Studied residences were built in the mid-20th century, indicating that VOC emissions even from older buildings and their contents can substantially contribute to occupant exposures.

Wildfires have become more common and intense in the western US over recent decades due to a combination of historical land management practices and warming climate. Emissions from large-scale fires now frequently affect populated regions such as the San Francisco Bay Area during the fall wildfire season, with documented impacts of the resulting particulate matter on human health. Health impacts of exposure to wildfire emissions depend on the chemical composition of particulate matter, but the molecular composition of the real biomass burning organic aerosol (BBOA) that reaches large population centers remains insufficiently characterized. We took PM 2.5 (particles having aerodynamic diameters less than or equal to 2.5 µm ) samples at the University of California, Berkeley campus ( ∼ 60 km downwind of the fires) during the October 2017 Northern California wildfires period and analyzed molecular composition of OA using a two-dimensional gas chromatography coupled with high-resolution time-of-flight mass spectrometry (GC × GC HR-ToF-MS). Sugar-like compounds were the most abundant component of BBOA, followed by mono-carboxylic acids, aromatic compounds, other oxygenated compounds, and terpenoids. The vast majority of compounds detected in smoke have unknown health impacts. Regression models were trained to predict the saturation vapor pressure and averaged carbon oxidation state ( OS c ‾ ) of detected compounds. The compounds speciated have a wide volatility distribution and most of them are highly oxygenated. In addition, time series of primary BBOA tracers observed in Berkeley were found to be indicative of the types of plants in the ecosystems burned in Napa and Sonoma, and could be used to differentiate the regions from which the smoke must have originated. Commonly used secondary BBOA markers like 4-nitrocatechol were enhanced when plumes aged, but their very fast formation caused them to have similar temporal variation as primary BBOA tracers. Using hierarchical clustering analysis, we classified compounds into seven factors indicative of their sources and transformation processes, identifying a unique daytime secondary BBOA factor. Chemicals associated with this factor include multifunctional acids and oxygenated aromatic compounds. These compounds have high OS c ‾ , and they are also semi-volatile. We observed no net particle-phase organic carbon formation, which indicates an approximate balance between the mass of evaporated organic carbonaceous compounds and the addition of secondary organic carbonaceous compounds.

Gas- and particle–phase molecular markers provide highly specific information about the sources and atmospheric processes that contribute to air pollution. In urban areas, major sources of pollution are changing as regulation selectively mitigates some pollution sources and climate change impacts the surrounding environment. In this study, a Comprehensive Thermal Desorption Aerosol Gas Chromatograph (cTAG) was used to measure volatile, intermediate volatility, and semi-volatile molecular markers every other hour over a 10-day period from 11 April to 21 April 2018 in suburban Livermore, California. Source apportionment via Positive Matrix Factorization (PMF) was performed to identify major sources of pollution. The PMF analysis identified 13 components, including emissions from gasoline, consumer products, biomass burning, secondary oxidation, aged regional transport, and several factors associated with single compounds or specific events with unique compositions. The gasoline factor had a distinct morning peak in concentration but lacked a corresponding evening peak, suggesting commute-related traffic emissions are dominated by cold starts in residential areas. More monoterpene and monoterpenoid mass was assigned to consumer product emissions than biogenic sources, underscoring the increasing importance of volatile chemical products to urban emissions. Daytime isoprene concentrations were controlled by biogenic sunlight- and temperature-dependent processes, mediated by strong midday mixing, but gasoline was found to be the dominant and likely only source of isoprene at night. Biomass burning markers indicated residential wood burning activity remained an important pollution source even in the springtime. This study demonstrates the utility of specific high-time-resolution molecular marker measurements across a wide range of volatility in more comprehensively describing pollution source profiles than a narrower volatility range would allow.

The rise and fall of estrogen and progesterone across menstrual cycles and during pregnancy regulates breast development and modifies cancer risk. How these hormones impact each cell type in the breast remains poorly understood because they act indirectly through paracrine networks. Using single-cell analysis of premenopausal breast tissue, we reveal a network of coordinated transcriptional programs representing the tissue-level response to changing hormone levels. Our computational approach, DECIPHER-seq, leverages person-to-person variability in breast composition and cell state to uncover programs that co-vary across individuals. We use differences in cell-type proportions to infer a subset of programs that arise from direct cell-cell interactions regulated by hormones. Further, we demonstrate that prior pregnancy and obesity modify hormone responsiveness through distinct mechanisms: obesity reduces the proportion of hormone-responsive cells, whereas pregnancy dampens the direct response of these cells to hormones. Together, these results provide a comprehensive map of the cycling human breast.

The chemical composition of ambient organic aerosols plays a critical role in driving their climate and health relevant properties and holds important clues to the sources and formation mechanisms of secondary aerosol material. In most ambient atmospheric environments, this composition remains incompletely characterized, with the number of identifiable species consistently outnumbered by those that have no mass spectral matches in the literature or NIST/NIH/EPA mass spectral databases, making them nearly impossible to definitively identify. This creates significant challenges in utilizing the full analytical capabilities of techniques which separate and generate spectra for complex environmental samples. In this work, we develop the use of machine learning techniques to quantify and characterize novel, or unidentifiable, organic material. This work introduces Ch3MS-RF (Chemical Characterization by Chromatography-Mass Spec Random Forest Modelling), an open-source R-based software tool for efficient machine-learning enabled characterization of compounds separated in chromatography-mass spec applications but not identifiable by comparison to mass spectral databases. A random forest model is trained and tested on a known 130 component representative external standard to predict the response factors of novel environmental organics based on position in volatility-polarity space and mass spectrum, enabling reproducible, efficient, and optimized quantification of novel environmental species. Quantification accuracy on a reserved 20 % test set randomly split from the external standard compound list indicate that random forest modelling significantly outperforms the commonly used methods in both precision and accuracy, with a median response factor % error of -2 % for modelled response factors compared to > 15 % for typically used proxy assignment-based methods. Chemical properties modelling, evaluated on the same reserved 20 % test set as well as an extrapolation set of species identified in ambient organic aerosol samples collected in the amazon rainforest, also demonstrates robust performance. Extrapolation set property prediction mean average errors for carbon number, oxygen to carbon ratio (O : C), average carbon oxidation state , and vapor pressure are 1.8, 0.15, 0.25, and 1.0 (log(atm)), respectively. Extrapolation set Out-of-Sample R2 for all properties modelled are above 0.75, with the exception of vapor pressure. While predictive performance for vapor pressure is less robust compared to the other chemical properties modelled, random forest-based modelling was significantly more accurate than other commonly used methods of vapor pressure prediction, decreasing mean average vapor pressure prediction error to 0.24 (log(atm)) from 0.55 (log(atm)) (chromatography-based vapor pressure prediction) and 1.2 (log(atm)) (chemical formula-based vapor pressure prediction). The random forest model significantly advances untargeted analysis of the full scope of chemical speciation yielded by GCxGC-MS techniques and can be applied to GC-MS as well. It enables accurate estimation of key chemical properties commonly utilized in the atmospheric chemistry community, which may be used to more efficiently identify important tracers for further individual analysis and to characterize compound populations uniquely formed under specific ambient conditions.

Background: COVID-19 disease as caused by a coronavirus called SARS-CoV-2 has taken the world by storm with upwards of 8 million confirmed infections in more than 190 countries. At the writing of this article, over 2 million Americans are confirmed infected and 117,000 have died. Rapid changes to manage COVID-19 care creates significant physical and emotional stress for healthcare employees, including pharmacy staff. Objective: This article provides pharmacy leaders with advice in leading through COVID-19 to promote staff resiliency. Methods: The specific leadership strategies include: (1) identifying and addressing fundamental needs; (2) communicating updated and reliable information; and (3) providing psychological and mental health support. Conclusion: Using various techniques described will help to preserve workforce resilience in providing patient-centered pharmacy services. After reading this article, pharmacy directors will have strategies and resources to maintain employee resiliency during this difficult time.

Organic emissions from coastal waters play an important but poorly understood role in atmospheric chemistry in coastal regions. A mesocosm experiment focusing on facilitated biological blooms in coastal seawater, SeaSCAPE (Sea Spray Chemistry and Particle Evolution), was performed to study emission of volatile gases, primary sea spray aerosol, and formation of secondary marine aerosol as a function of ocean biological and chemical processes. Here, we report observations of aerosol-phase benzothiazoles in a marine atmospheric context with complementary measurements of dissolved-phase benzothiazoles. Though previously reported dissolved in polluted coastal waters, we report the first direct evidence of the transfer of these molecules from seawater into the atmosphere. We also report the first gas-phase observations of benzothiazole in the environment absent a direct industrial, urban, or rubber-based source. From the identities and temporal dynamics of the dissolved and aerosol species, we conclude that the presence of benzothiazoles in the coastal water (and thereby their emissions into the atmosphere) is primarily attributable to anthropogenic sources. Oxidation experiments to explore the atmospheric fate of gas-phase benzothiazole show that it produces secondary aerosol and gas-phase SO2, making it a potential contributor to secondary marine aerosol formation in coastal regions and a participant in atmospheric sulfur chemistry.

Background: A safe medication error reporting culture is one that promotes, fosters, and rewards the reporting of errors and events across the spectrum of harm (none to significant harm). For this culture to develop, leaders must key department cultural norms. These cultural norms include making employees feel psychologically safe to report errors, and to establish a culture of error review and follow-up that complies with best practices. Objective: This article reviews how pharmacy leaders can establish this environment by describing (1) setting an appropriate vision for safety as a priority; (2) establishing and actively supporting the concept of psychological safety; and (3) implementing medication error review that support an effective safety culture. Finally, the article discusses a case where the relationships between psychological safety, safety culture, and reporting culture are described. Methods: This article reviews the literature and authors’ experiences in designing a safety culture for a pharmacy department. Concluson: A safe reporting culture requires leaders to be humble, engage their staff in dialogue, objectively measure culture, consistently provide feedback, and empower its people. Employing these leadership traits with best practices can improve overall medication safety and the quality of patient-centered pharmacy services.

Background: Maintaining integrity of the pharmaceutical supply chain is critical to providing medications that are free from adulteration (counterfeit, substandard or unapproved medications), making them safe for patient use. Purchasing pharmaceuticals through the Internet can be associated with a risk of receiving adulterated medicines. Objective: The objective of this study was to review the current threats to maintaining a secure pharmaceutical supply chain, specifically focused on Internet-based procurement of medications. Methods: A review of the literature was conducted along with collating important up to date resources and other publications that provide foundational information to understanding the risks and prevention strategies for online purchasing of pharmaceuticals. Conclusion: The information provided in this article helps to properly inform pharmacy leaders to the resources available to protect against the risks of on-line purchasing of pharmaceuticals.

Background: Opioid use is classified as an epidemic by many due to the impact of these medications on society. Federal and state laws for prescribing and dispensing opioids have changed rapidly in a short period of time to hopefully balance proper pain control with their use. Pharmacy directors must be informed of these rapid changes to effectively work as part of any opioid stewardship team. Objective: The objective of this study was to provide foundational leadership guidance to pharmacy directors on current opioid legislation, literature, and best practices to assist in improving opioid use. Methods: A review of the literature from 2003 to the present was conducted along with collating important up to date resources and other publications that provide foundational information to help support a comprehensive management of opioid use. A summary of these data has been collated into an easy to use table and summarized throughout this article. Conclusion: The information provided in this article helps to properly inform pharmacy leaders to the resources available to improve the prescribing, dispensing, and monitoring of opioids and alternatives.

Aerosols are a source of great uncertainty in radiative forcing predictions and have poorly understood health impacts. Most aerosol mass is formed in the atmosphere from reactive gas phase organic precursors, forming secondary organic aerosol (SOA). Semivolatile organic compounds (SVOCs) (effective saturation concentration, C*, of 10−1–103 μg m−3) comprise a large fraction of organic aerosol, while intermediate volatility organic compounds (IVOCs) (C* of 103–106 μg m−3) and volatile organic compounds (VOCs) (C* ≥ 106 μg m−3) are gas phase precursors to SOA and ozone. The Comprehensive Thermal Desorption Aerosol Gas Chromatograph (cTAG) is the first single instrument simultaneously quantitative for a broad range of compound-specific VOCs, IVOCs and SVOCs. cTAG is a two-channel instrument which measures concentrations of C5–C16 alkane equivalent volatility VOCs and IVOCs on one channel and C14–C32 SVOCs on the other coupled to a single High Resolution Time of Flight Mass Spectrometer, achieving consistent quantification across 15 orders of magnitude of vapor pressure. cTAG obtains concentrations hourly and gas–particle partitioning for SVOCs bihourly, enabling observation of the evolution of these species through oxidation and partitioning into the particle phase. Online derivatization for the SVOC channel enables detection of more polar and oxidized species. In this work we present design details and data evaluating key parameters of instrument performance such as I/VOC collector design optimization, linearity and reproducibility of calibration curves obtained using a custom liquid evaporation system for I/VOCs and the effect of an ozone removal filter on instrument performance. Example timelines of precursors with secondary products are shown and analysis of a subset of compounds detectable by cTAG demonstrates some of the analytical possibilities with this instrument.

Purified populations of cells can be reconstituted into organoids that recapitulate aspects of their in vivo structure and function. These organoids are useful as models of healthy and diseased tissue in the basic sciences, in vitro screens, and regenerative medicine. Existing strategies to reconstitute organoids from purified cells face obstacles with respect to cell-viability, multicellular connectivity, scalability, and compatibility with subsequent experimental or analytical techniques. To address these challenges, we developed a strategy for rapidly casting populations of cells into microtissues of prescribed size and shape. This approach begins by chemically remodeling the adhesive properties of living cells with membrane-anchored ssDNA with modest annealing kinetics. Populations of complementary labeled cells are then combined into microwells that rapidly mold the DNA-adhesive cell populations into 3D aggregates of uniform size and shape. Once formed, aggregates are removed from the molds in the presence of "capping" oligonucleotides that block hybridization of residual surface DNA between aggregates in suspension. Finally, transfer of aggregates to biomimetic gels for 3D culture completes the process of reconstitution. This strategy of chemical micromolding allows for control over aggregate internal topology and does not perturb the natural process of self-organization in primary human mammary epithelial cells.

Wildfires have become more common and intense in the western US over recent decades due to a combination of historical land management and warming climate. Emissions from large scale fires now frequently affect populated regions such as the San Francisco Bay Area during the fall wildfire season, with documented impacts of the resulting particulate matter on human health. Health impacts of exposure to wildfire emissions depend on the chemical composition of particulate matter, but the molecular composition of the real biomass burning organic aerosol (BBOA) that reaches large population centers remains insufficiently characterized. We took PM2.5 (particles having aerodynamic diameters less than or equal to 2.5 μm) samples at the University of California, Berkeley campus (~60 km downwind of the fires) during the October 2017 Northern California wildfires period, and analyzed molecular composition of OA using a two-dimensional gas-chromatography coupled with high resolution time-of-flight mass spectrometer (GC×GC ToFMS). Sugar-like compounds were the most abundant component of BBOA, followed by mono-carboxylic acids, aromatic compounds, other oxygenated compounds and terpenoids. The vast majority of compounds detected in smoke have unknown health impacts. Regression models were trained to predict the saturation vapor pressure and averaged carbon oxidation state of compounds. The compounds speciated have a wide volatility distribution and most of them are highly oxygenated. In addition, time series of primary BBOA tracers observed in Berkeley were found to be indicative of the types of plants in the ecosystems burned in Napa and Sonoma, and could be used to differentiate the regions from which the smoke must have originated. Commonly used secondary BBOA markers like 4-nitrocatechol were enhanced when plumes aged, but their very fast formation caused them to have similar temporal variation as primary BBOA tracers. Using hierarchical clustering analysis, we classified compounds into 7 factors indicative of their sources and transformation processes, identifying a unique daytime secondary BBOA factor. Chemicals associated with this factor include multifunctional acids and oxygenated aromatic compounds. These compounds have high average carbon oxidation state, and are also semivolatile. We observed no net particle-phase organic carbon formation, which indicates an approximate balance between the mass of evaporated primary and secondary organic carbonaceous compounds to the addition of secondary organic carbonaceous compounds.

In our previous works, we presented a method to increase the harvested energy from vibrations using a piezoelectric cantilever and to increase the frequency range of operation by introducing bistability with the use of magnetic repulsion. However, for small excitations, the cantilever may not be able to overcome the magnetic repulsive force but vibrate at one of its two equilibrium positions with reduced amplitude. This work introduces a method of increasing the range of excitations over which the operation remains bistable. This is achieved by spring loading one of the magnets, previously on a fixed support, allowing motion in one dimension only, toward and away from the cantilever in the horizontal plane. Configured so, as the cantilever moves toward this magnet, the repulsion due to the cantilever-mounted magnet pushes the spring-loaded magnet away, increasing distance, and thus, reducing magnetic force between them, required to be overcome by external excitations for bistable operation. Similarly, as the cantilever moves away, the spring pushes the magnet closer to the cantilever-mounted magnet, increasing vibration amplitude. Thus, the spring introduces a negative feedback which favors bistable operation over an increased range of excitations. This completely mechanical method requires no additional energy cost. Peak power gains of up to 90 and a decrease in excitation voltage of up to 60% were observed over the fixed magnet.

Biosouring in crude oil reservoirs by sulfate-reducing microbial communities (SRCs) results in hydrogen sulfide production, precipitation of metal sulfide complexes, increased industrial costs of petroleum production, and exposure issues for personnel. Potential treatment strategies include nitrate or perchlorate injections into reservoirs. Gas chromatography with vacuum ultraviolet ionization and high-resolution time-of-flight mass spectrometry (GC-VUV-HTOF) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) combined with electrospray ionization were applied in this study to identify hydrocarbon degradation patterns and product formations in crude oil samples from biosoured, nitrate-treated, and perchlorate-treated bioreactor column experiments. Crude oil hydrocarbons were selectively transformed based on molecular weight and compound class in the biosouring control environment. Both the nitrate and the perchlorate treatments significantly reduced sulfide production; however, the nitrate treatment enhanced crude oil biotransformation, while the perchlorate treatment inhibited crude oil biotransformation. Nitrogen- and oxygen-containing biodegradation products, particularly with chemical formulas consistent with monocarboxylic and dicarboxylic acids containing 10-60 carbon atoms, were observed in the oil samples from both the souring control and the nitrate-treated columns but were not observed in the oil samples from the perchlorate-treated column. These results demonstrate that hydrocarbon degradation and product formation of crude oil can span hydrocarbon isomers and molecular weights up to C

Integration of cyber technologies with agriculture provides opportunities for precision agriculture. It requires buried underground sensors to provide useful content information to the end-user for crop management. In our earlier studies, we developed an impedance measurement-based in-situ wireless soil moisture and salinity sensor, an electrophoretic sensor for measuring soil ions/nutrients, and nano-patterned plasmonic-resonance, as well as guided-mode resonance-based optical sensors for the plant, released volatile organic compounds. Here we present a physics-based approach to infer the moisture and ionic concentration in the soil from in-situ, multi-frequency measurements of the impedance of a metamaterial-inspired sensing element buried underground. Such model holds the advantage over empirical models by obviating the need to redo the calibration for different soil types. Our method involves performing an inversion analysis on the Bruggeman’s dielectric mixing model. Under the quasi-static assumption, the approach predicts volumetric moisture content and ion concentration with 90% accuracy in terms of the molar fraction of total volume for silver nitrate concentrations of 0 to 100 mM. We observed that soil conductivity is near-linear to the inferred ionic concentration for a given saline water fraction in the soil. The model has been validated by making multi-frequency impedance measurements of a soil mixture at different concentrations comprising of various constituents of soil, air, water, and ions.

The ability to structurally characterize and isomerically quantify crude oil hydrocarbons relevant to refined fuels such as motor oil, diesel, and gasoline represents an extreme challenge for chromatographic and mass spectrometric techniques. This work incorporates two-dimensional gas chromatography coupled to a tunable vacuum ultraviolet soft photoionization source, the Chemical Dynamics Beamline 9.0.2 of the Advanced Light Source at the Lawrence Berkeley National Laboratory, with a time-of-flight mass spectrometer (GC × GC-VUV-TOF) to directly characterize and isomerically sum the contributions of aromatic and aliphatic species to hydrocarbon classes of four crude oils. When the VUV beam is tuned to 10.5 ± 0.2 eV, both aromatic and aliphatic crude oil hydrocarbons are ionized to reveal the complete chemical abundance of C9–C30 hydrocarbons. When the VUV beam is tuned to 9.0 ± 0.2 eV only aromatic hydrocarbons are ionized, allowing separation of the aliphatic and aromatic fractions of the crude oil hydrocarbon chemical classes in an efficient manner while maintaining isomeric quantification. This technique provides an effective tool to determine the isomerically summed aromatic and aliphatic hydrocarbon compositions of crude oil, providing information that goes beyond typical GC × GC separations of the most dominant hydrocarbon isomers.

Pulsed magnetic field generation is a critical aspect of all nuclear magnetic resonance (NMR) experiments. In this paper, a novel design for a low field, low frequency (less than 5 MHz), pulsed magnetic field generation circuit suited for unilateral NMR applications is presented. A pulsed sinusoidal current is generated at an inductive load connected to an FET-based switch. The inductive load resonates at a frequency of approximately 2 MHz, which is also the precession frequency of $^{1}H$ protons in an external magnetic flux density of 500 G. The designed circuit can be tuned to operate at resonant frequencies of other chemical species as well. In this paper, the design parameters and operation of the prototype pulsed field generator will be discussed.