Predictors of Pediatric Asthma Management: Identifying Actionable Results With Geographic Determinants.

BACKGROUND: Pediatric asthma remains one of the most prominent chronic health conditions among US youth. Geographic determinants such as air pollutants have been identified as playing a role in asthma development and exacerbation. The purpose of this study was to determine geospatial predictors of pediatric asthma exacerbation events and to prioritize housing remediation resources. METHODS: Electronic medical records were abstracted from a health plan in Southern California. The inclusion criteria that created a sample of 51 557 members were those aged 21 years and younger, who had at least 1 asthma-related encounter between January 2019 and December 2021. Diagnoses, age, number of clinic and emergency department visits, and home addresses were included. The air quality index from the closest monitoring station during the study period, residential distance from a primary roadway, and residential distance from manufacturing sites were included in the spatial analysis. RESULTS: The average number of asthma-related clinic visits was 2 across the sample. Individuals with more asthma-related clinic visits residing in public housing were more likely to live within 4 km of industrial manufacturing locations ( P < .001), reside closer to a major roadway ( P < .001), and experience a higher number of poor air quality days ( P < .001). Modeling results show these factors were also significantly predictive of an increase of asthma-related health care encounters. CONCLUSIONS: The findings of this study were consistent with previous studies linking asthma and poor air quality and further highlighted some of the additive and potentially exponential challenges that public housing, major roadways, and manufacturing sites provide communities in their proximity. This research can guide environmental interventions, including the frequency of public housing inspections, community outreach, and the development of communication strategies, to reduce asthma-related experiences across neighborhoods.

Identification of oil contamination in process water using fluorescence excitation emission matrix (FEEM) and parallel factor analysis (PARAFAC).

Fuel oil is widely used within Eskom, a power generation company in South Africa. Eskom's coal-fired power stations use up to 30,000 L of fuel oil per hour during a cold start-up, a consequence of which results in oil leaks to the dams. Oil contamination in water treatment plants causes irreversible membrane fouling, requiring costly replacement. This research work focused on the development of a rapid method for the identification of low concentrations of the water-soluble oil component fraction of crude fuel oil. For the developed method, known volumes of the water-soluble fraction of crude oil were spiked into various matrices of process water. FEEMs were collected using the patented HORIBA Aqualog spectrometer and data were modelled with PARAFAC. The results were well described with a four-component model, which included an oil component and three natural organic matter components, with a split-half validation match of 90%. The oil component was verified using linear regression of the PARAFAC component scores yielding an R2 value of 0.98. From the scores, a qualitative pass/fail test was developed such that process water can be analysed and subjected to the model to indicate the presence of oil contamination beyond a damaging threshold.

An optimised and validated surrogate analyte A-TEEM-PARAFAC-PLS technique for detecting and quantifying the biological oxygen demand in surface water.

A 5-day test duration makes BOD5 measurement unsatisfactory and hinders the development of a quick technique. Protein-like fluorescence peaks show a strong correlation between the BOD characteristics and the fluorescence intensities. For identifying and measuring BOD in surface water, a simultaneous absorbance-transmittance and fluorescence excitation-emission matrices (A-TEEM) method combined with PARAFAC (parallel factor) and PLS (partial least squares) analyses was developed using a tyrosine and tryptophan (tyr-trpt) mix as a surrogate analyte for BOD. The use of a surrogate analyte was decided upon due to lack of fluorescent BOD standards. Tyr-trpt mix standard solutions were added to surface water samples to prepare calibration and validation samples. PARAFAC analysis of excitation-emission matrices detected the tyr-trpt mix in surface water. PLS modelling demonstrated significant linearity (R2 = 0.991) between the predicted and measured tyr-trypt mix concentrations, and accuracy and robustness were all acceptable per the ICH Q2 (R2) and ASTM multivariate calibration/validation procedures guidelines. Based on a suitable and workable surrogate analyte method, these results imply that BOD can be detected and quantified using the A-TEEM-PARAFAC-PLS method. Very positive comparability between tyr-trypt mix concentrations was found, suggesting that tyr-trypt mix might eventually take the place of a BOD-based sampling protocol. Overall, this approach offers a novel tool that can be quickly applied in water treatment plant settings and is a step in supporting the trend toward rapid BOD determination in waters. Further studies should demonstrate the wide application of the method using real wastewater samples from various water treatment facilities.

Detection and Quantification of Bisphenol A in Surface Water Using Absorbance-Transmittance and Fluorescence Excitation-Emission Matrices (A-TEEM) Coupled with Multiway Techniques.

In the present protocol, we determined the presence and concentrations of bisphenol A (BPA) spiked in surface water samples using EEM fluorescence spectroscopy in conjunction with modelling using partial least squares (PLS) and parallel factor (PARAFAC). PARAFAC modelling of the EEM fluorescence data obtained from surface water samples contaminated with BPA unraveled four fluorophores including BPA. The best outcomes were obtained for BPA concentration (R2 = 0.996; standard deviation to prediction error's root mean square ratio (RPD) = 3.41; and a Pearson's r value of 0.998). With these values of R2 and Pearson's r, the PLS model showed a strong correlation between the predicted and measured BPA concentrations. The detection and quantification limits of the method were 3.512 and 11.708 micro molar (µM), respectively. In conclusion, BPA can be precisely detected and its concentration in surface water predicted using the PARAFAC and PLS models developed in this study and fluorescence EEM data collected from BPA-contaminated water. It is necessary to spatially relate surface water contamination data with other datasets in order to connect drinking water quality issues with health, environmental restoration, and environmental justice concerns.

Absorbance-Transmittance Excitation Emission Matrix Method for Quantification of Major Cannabinoids and Corresponding Acids: A Rapid Alternative to Chromatography for Rapid Chemotype Discrimination of Cannabis sativa Varieties.

Background: Phytocannabinoids naturally occur in the cannabis plant (Cannabis sativa), and Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) predominate. There is a need for rapid inexpensive methods to quantify total THC (for statutory definition) and THC-CBD ratio (for classification into three chemotypes). This study explores the capabilities of a spectroscopic technique that combines ultraviolet-visible and fluorescence, absorbance-transmittance excitation emission matrix (A-TEEM). Methods: The A-TEEM technique classifies 49 dry flower extracts into three C. sativa chemotypes, and quantifies the total THC-CBD ratio, using validated gas chromatography (GC)-flame ionization (FID) and High-Performance Liquid Chromatography (HPLC) methods for reference. Multivariate methods used are principal components analysis for a chemotype classification, extreme gradient boost (XGB) discriminant analysis (DA) to classify unknown samples by chemotype, and XGB regression to quantify total THC and CBD content using GC-FID and HPLC data on the same samples. Results: The A-TEEM technique provides robust classification of C. sativa samples, predicting chemotype classification, defined by THC-CBD content, of unknown samples with 100% accuracy. In addition, A-TEEM can quantify total THC and CBD levels relevant to statutory determination, with limit of quantifications (LOQs) of 0.061% (THC) and 0.059% (CBD), and high cross-validation (>0.99) and prediction (>0.99), using a GC-FID method for reference data; and LOQs of 0.026% (THC) and 0.080% (CBD) with high cross-validation (>0.98) and prediction (>0.98), using an HPLC method for reference data. A-TEEM is highly predictive in separately quantifying acid and neutral forms of THC and CBD with HPLC reference data. Conclusions: The A-TEEM technique provides a sensitive method for the qualitative and quantitative characterization of the major cannabinoids in solution, with LOQs comparable with GC-FID and HPLC, and high values of cross-validation and prediction. As a spectroscopic technique, it is rapid, with data acquisition <45 sec per measurement; sample preparation is simple, requiring only solvent extraction. A-TEEM has the sensitivity to resolve and quantify cannabinoids in solution based on their unique spectral characteristics. Discrimination of legal and illegal chemotypes can be rapidly verified using XGB DA, and quantitation of statutory levels of total THC and total CBD comparable with GC-FID and HPLC can be obtained using XBD regression.

Machine learning for classifying and predicting grape maturity indices using absorbance and fluorescence spectra.

Absorbance-transmission and fluorescence excitation-emission matrix (A-TEEM) spectroscopy was investigated as a rapid method for predicting maturity indices using Cabernet Sauvignon grapes produced under four viticulture treatments during two growing seasons. Machine learning models were developed with fused spectral data to predict 3-isobutyl-2-methoxypyrazine (IBMP), pH, total tannins (Tannin), total soluble solids (TSS), and malic and tartaric acids based on the results from traditional analysis methods. Extreme gradient boosting (XGB) regression yielded R2 values of 0.92-0.96 for IBMP, malic acid, pH, and TSS for externally validated (Test) models, with partial least squares regression being superior for TSS prediction (R2 = 0.97). R2 values of 0.64-0.81 were achieved with either approach for tartaric acid and Tannin predictions. Classification of grape maturity, defined by quantile ranges for red colour, IBMP, malic acid, and TSS, was investigated using XGB discriminant analysis, providing an average of 78 % correctly classified samples for the Test model.

Determination of Cabernet Sauvignon wine quality parameters in Chile by Absorbance-Transmission and fluorescence Excitation Emission Matrix (A-TEEM) spectroscopy.

A-TEEM spectroscopy is presented as a novel rapid quantitative analysis method for 44 individual phenolic and basic wine chemistry compounds. To date no practical and combined analysis method for these recognized quality parameters important to the wine industry exists. The method was implemented in a Lambert-Beer linear concentration range to facilitate traceable absorbance and fluorescence spectral signatures. Both components were comparatively analyzed as single- and combined multi-block variable sets, and regressed against HPLC-DAD, UV-vis spectroscopy and other analytical reference data, using the Extreme Gradient Boost Regression (XGBR) and Partial Least Squares Regression (PLSR) algorithms. The approach was applied on 126 wines, and subsequently validated by a random split of 13% of the set and an additional independent set of 16 wines. XGBR with multi-block data organization systematically yielded the highest prediction accuracy and precision with respective overall valid fits indicated by mean R2 and relative bias of 0.94 ± 0.04 and 4.1 ± 1.8%.

Spectrofluorometric analysis combined with machine learning for geographical and varietal authentication, and prediction of phenolic compound concentrations in red wine.

Fluorescence spectroscopy is rapid, straightforward, selective, and sensitive, and can provide the molecular fingerprint of a sample based on the presence of various fluorophores. In conjunction with chemometrics, fluorescence techniques have been applied to the analysis and classification of an array of products of agricultural origin. Recognising that fluorescence spectroscopy offered a promising method for wine authentication, this study investigated the unique use of an absorbance-transmission and fluorescence excitation emission matrix (A-TEEM) technique for classification of red wines with respect to variety and geographical origin. Multi-block data analysis of A-TEEM data with extreme gradient boosting discriminant analysis yielded an unrivalled 100% and 99.7% correct class assignment for variety and region of origin, respectively. Prediction of phenolic compound concentrations with A-TEEM based on multivariate calibration models using HPLC reference data was also highly effective, and overall, the A-TEEM technique was shown to be a powerful tool for wine classification and analysis.

Authentication of the geographical origin of Australian Cabernet Sauvignon wines using spectrofluorometric and multi-element analyses with multivariate statistical modelling.

With the increased risk of wine fraud, a rapid and simple method for wine authentication has become a necessity for the global wine industry. The use of fluorescence data from an absorbance and transmission excitation-emission matrix (A-TEEM) technique for discrimination of wines according to geographical origin was investigated in comparison to inductively coupled plasma-mass spectrometry (ICP-MS). The two approaches were applied to commercial Cabernet Sauvignon wines from vintage 2015 originating from three wine regions of Australia, along with Bordeaux, France. Extreme gradient boosting discriminant analysis (XGBDA) was examined among other multivariate algorithms for classification of wines. Models were cross-validated and performance was described in terms of sensitivity, specificity, and accuracy. XGBDA classification afforded 100% correct class assignment for all tested regions using the EEM of each sample, and overall 97.7% for ICP-MS. The novel combination of A-TEEM and XGBDA was found to have great potential for accurate authentication of wines.

A novel source of arterial valve cells linked to bicuspid aortic valve without raphe in mice.

Abnormalities of the arterial valve leaflets, predominantly bicuspid aortic valve, are the commonest congenital malformations. Although many studies have investigated the development of the arterial valves, it has been assumed that, as with the atrioventricular valves, endocardial to mesenchymal transition (EndMT) is the predominant mechanism. We show that arterial is distinctly different from atrioventricular valve formation. Whilst the four septal valve leaflets are dominated by NCC and EndMT-derived cells, the intercalated leaflets differentiate directly from Tnnt2-Cre+/Isl1+ progenitors in the outflow wall, via a Notch-Jag dependent mechanism. Further, when this novel group of progenitors are disrupted, development of the intercalated leaflets is disrupted, resulting in leaflet dysplasia and bicuspid valves without raphe, most commonly affecting the aortic valve. This study thus overturns the dogma that heart valves are formed principally by EndMT, identifies a new source of valve interstitial cells, and provides a novel mechanism for causation of bicuspid aortic valves without raphe.

Identification of Degradation Pathways of Chlorohydrocarbons in Saturated Low-Permeability Sediments Using Compound-Specific Isotope Analysis.

This study aims to investigate whether compound-specific carbon isotope analysis (CSIA) can be used to differentiate the degradation pathways of chlorohydrocarbons in saturated low-permeability sediments. For that purpose, a site was selected, where a complex mixture of chlorohydrocarbons contaminated an aquifer-aquitard system. Almost 50 years after contaminant releases, high-resolution concentration, CSIA, and microbial profiles were determined. The CSIA profiles showed that in the aquitard cis-dichloroethene (cDCE), first considered as a degradation product of trichloroethene (TCE), is produced by the dichloroelimination of 1,1,2,2-tetrachloroethane (TeCA). In contrast, TeCA degrades to TCE via dehydrohalogenation in the aquifer, indicating that the aquifer-aquitard interface separates two different degradation pathways for TeCA. Moreover, the CSIA profiles showed that chloroform (CF) is degraded to dichloromethane (DCM) via hydrogenolysis in the aquitard and, to a minor degree, produced by the degradation of carbon tetrachloride (CT). Several microorganisms capable of degrading chlorohydrocarbons were detected in the aquitard, suggesting that aquitard degradation is microbially mediated. Furthermore, numerical simulations reproduced the aquitard concentration and CSIA profiles well, which allowed the determination of degradation rates for each transformation pathway. This improves the prediction of contaminant fate in the aquitard and potential magnitude of impacts on the adjacent aquifer due to back-diffusion.

A-TEEMTM, a new molecular fingerprinting technique: simultaneous absorbance-transmission and fluorescence excitation-emission matrix method.

We investigate the new simultaneous absorbance-transmission and fluorescence excitation-emission matrix method for rapid and effective characterization of the varying components from a mixture. The absorbance-transmission and fluorescence excitation-emission matrix method uniquely facilitates correction of fluorescence inner-filter effects to yield quantitative fluorescence spectral information that is largely independent of component concentration. This is significant because it allows one to effectively monitor quantitative component changes using multivariate methods and to generate and evaluate spectral libraries. We present the use of this novel instrument in different fields: i.e. tracking changes in complex mixtures including natural water, wine as well as monitoring stability and aggregation of hormones for biotherapeutics.

What Lies Beneath: Wnt/ß-Catenin Signaling and Cell Fate in the Lower Dermis.

Dermal cell populations are markedly heterogeneous, and they have the capacity to differentiate into dynamic and complex dermal cell compartments. However, the regulatory processes that govern the establishment of each dermal subset remain unknown. Mastrogiannaki et al. provide evidence of Wnt/ß-catenin signaling controlling adipogenic differentiation in the developing reticular dermis. They also show that overexpression of localized Wnt converts dermal adipose cells into a distinct fibroblast subtype, which leads to fibrosis and disrupted hair follicle cycling. These findings highlight the multifaceted roles of Wnt signaling in the normal development and pathology of skin, including the establishment of dermal identity. Further understanding of Wnt involvement and uncovering the roles of specific Wnt ligands could be useful for discovering new therapeutic targets in treating fibrosis-related disorders.

How to Collect National Institute of Standards and Technology (NIST) Traceable Fluorescence Excitation and Emission Spectra.

Contemporary spectrofluorimeters comprise exciting light sources, excitation and emission monochromators, and detectors that without correction yield data not conforming to an ideal spectral response. The correction of the spectral properties of the exciting and emission light paths first requires calibration of the wavelength and spectral accuracy. The exciting beam path can be corrected up to the sample position using a spectrally corrected reference detection system. The corrected reference response accounts for both the spectral intensity and drift of the exciting light source relative to emission and/or transmission detector responses. The emission detection path must also be corrected for the combined spectral bias of the sample compartment optics, emission monochromator, and detector. There are several crucial issues associated with both excitation and emission correction including the requirement to account for spectral band-pass and resolution, optical band-pass or neutral density filters, and the position and direction of polarizing elements in the light paths. In addition, secondary correction factors are described including (1) subtraction of the solvent's fluorescence background, (2) removal of Rayleigh and Raman scattering lines, as well as (3) correcting for sample concentration-dependent inner-filter effects. The importance of the National Institute of Standards and Technology (NIST) traceable calibration and correction protocols is explained in light of valid intra- and interlaboratory studies and effective spectral qualitative and quantitative analyses including multivariate spectral modeling.

Regulation of photosynthetic light harvesting involves intrathylakoid lumen pH sensing by the PsbS protein.

The biochemical, biophysical, and physiological properties of the PsbS protein were studied in relation to mutations of two symmetry-related, lumen-exposed glutamate residues, Glu-122 and Glu-226. These two glutamates are targets for protonation during lumen acidification in excess light. Mutation of PsbS did not affect xanthophyll cycle pigment conversion or pool size. Plants containing PsbS mutations of both glutamates did not have any rapidly inducible nonphotochemical quenching (qE) and had similar chlorophyll fluorescence lifetime components as npq4-1, a psbS deletion mutant. The double mutant also lacked a characteristic leaf absorbance change at 535 nm (DeltaA535), and PsbS from these plants did not bind dicyclohexylcarbodiimide (DCCD), a known inhibitor of qE. Mutation of only one of the glutamates had intermediate effects on qE, chlorophyll fluorescence lifetime component amplitudes, DCCD binding, and DeltaA535. Little if any differences were observed comparing the two single mutants, suggesting that the glutamates are chemically and functionally equivalent. Based on these results a bifacial model for the functional interaction of PsbS with photosystem II is proposed. Furthermore, based on the extent of qE inhibition in the mutants, photochemical and nonphotochemical quenching processes of photosystem II were associated with distinct chlorophyll fluorescence life-time distribution components.

Simultaneous time resolution of the emission spectra of fluorescent proteins and zooxanthellar chlorophyll in reef-building corals.

Light is absorbed by photosynthetic algal symbionts (i.e. zooxanthellae) and by chromophoric fluorescent proteins (FP) in reef-building coral tissue. We used a streak-camera spectrograph equipped with a pulsed, blue laser diode (50 ps, 405 nm) to simultaneously resolve the fluorescence spectra and kinetics for both the FP and the zooxanthellae. Shallow water (<9 m)-dwelling Acropora spp. and Plesiastrea versipora specimens were collected from Okinawa, Japan, and Sydney, Australia, respectively. The main FP emitted light in the blue, blue-green and green emission regions with each species exhibiting distinct color morphs and spectra. All corals showed rapidly decaying species and reciprocal rises in greener emission components indicating Förster resonance energy transfer (FRET) between FP populations. The energy transfer modes were around 250 ps, and the main decay modes of the acceptor FP were typically 1900-2800 ps. All zooxanthellae emitted similar spectra and kinetics with peak emission (approximately 683 nm) mainly from photosystem II (PSII) chlorophyll (chl) a. Compared with the FP, the PSII emission exhibited similar rise times but much faster decay times, typically around 640-760 ps. The fluorescence kinetics and excitation versus emission mapping indicated that the FP emission played only a minor role, if any, in chl excitation. We thus suggest the FP could only indirectly act to absorb, screen and scatter light to protect PSII and underlying and surrounding animal tissue from excess visible and UV light. We conclude that our time-resolved spectral analysis and simulation revealed new FP emission components that would not be easily resolved at steady state because of their relatively rapid decays due to efficient FRET. We believe the methods show promise for future studies of coral bleaching and for potentially identifying FP species for use as genetic markers and FRET partners, like the related green FP from Aequorea spp.

PsbS-dependent enhancement of feedback de-excitation protects photosystem II from photoinhibition.

Feedback de-excitation (qE) regulates light harvesting in plants to prevent inhibition of photosynthesis when light absorption exceeds photosynthetic capacity. Although the mechanism of qE is not completely understood, it is known to require a low thylakoid lumen pH, de-epoxidized xanthophylls, and the photosystem II protein PsbS. During a short-term 4-h exposure to excess light, three PsbS- and qE-deficient Arabidopsis thaliana mutants that differed in xanthophyll composition were more photoinhibited than the wild type. The extent of photoinhibition was the same in all of the mutants, suggesting that qE capacity rather than xanthophyll composition is critical for photoprotection in short-term high light, in contrast to longer-term high light conditions (days) when additional antioxidant roles of specific xanthophylls are evident. Plants with a 2-fold increase in qE capacity were generated by overexpression of PsbS, demonstrating that the level of PsbS limits the qE capacity in wild-type Arabidopsis. These results are consistent with the idea that variations in PsbS expression are responsible for species-specific and environmentally induced differences in qE capacity observed in nature. Furthermore, plants with higher qE capacity were more resistant to photoinhibition than the wild type. Increased qE was associated with decreased photosystem II excitation pressure and changes in the fractional areas of chlorophyll a fluorescence lifetime distributions, but not the lifetime centers, suggesting that qE protects from photoinhibition by preventing overreduction of photosystem II electron acceptors. Engineering of qE capacity by PsbS overexpression could potentially yield crop plants that are more resistant to environmental stress.

Molecular and global time-resolved analysis of a psbS gene dosage effect on pH- and xanthophyll cycle-dependent nonphotochemical quenching in photosystem II.

Photosynthetic light harvesting in plants is regulated by a pH- and xanthophyll-dependent nonphotochemical quenching process (qE) that dissipates excess absorbed light energy and requires the psbS gene product. An Arabidopsis thaliana mutant, npq4-1, lacks qE because of a deletion of the psbS gene, yet it exhibits a semidominant phenotype. Here it is shown that the semidominance is due to a psbS gene dosage effect. Diploid Arabidopsis plants containing two psbS gene copies (wild-type), one psbS gene (npq4-1/NPQ4 heterozygote), and no psbS gene (npq4-1/npq4-1 homozygote) were compared. Heterozygous plants had 56% of the wild-type psbS mRNA level, 58% of the wild-type PsbS protein level, and 60% of the wild-type level of qE. Global analysis of the chlorophyll a fluorescence lifetime distributions revealed three components in wild-type and heterozygous plants, but only a single long lifetime component in npq4-1. The short lifetime distribution associated with qE was inhibited by more than 40% in heterozygous plants compared with the wild type. Thus, the extent of qE measured as either the fractional intensities of the PSII chlorophyll a fluorescence lifetime distributions or steady state intensities was stoichiometrically related to the amount of PsbS protein.