Data Gap: Air Quality Networks Miss Air Pollution from Concentrated Animal Feeding Operations.

In the U.S., the agricultural sector is the largest controllable source of several air pollutants, including ammonia (NH3), which is a key precursor to PM2.5 formation. Livestock waste is the dominant contributor to ammonia emissions. In contrast to most controllable air pollutants, satellite records show ammonia mixing ratios are rising. The number of confined animal feeding operations (CAFOs) that generate considerable livestock waste is also increasing. Spatial and temporal trends in USDA-reported animal numbers normalized by county area at medium and large CAFOs provide plausible explanations for patterns in satellite-derived NH3 over the contiguous U.S. (CONUS). The correlation between summertime ammonia derived from the European Space Agency's (ESA) Infrared Atmospheric Sounding Interferometer (IASI) and CAFO animal unit density in 2017 is positive and significant (r = 0.642; p ≈ 0). The temporal changes from 2002 to 2017 in animal unit density and NH3 derived from NASA's Atmospheric Infrared Sounder (AIRS) are spatially similar. Trends and ambient concentrations of PM2.5 mass in agricultural regions are difficult to assess relative to those of urban population centers given the sparseness of rural monitors in regulatory surface networks. Results suggest that in agricultural areas where ammonia concentrations and animal density are highest, air quality improvement lags behind the national average.

Ambient Aerosol Is Physically Larger on Cloudy Days in Bondville, Illinois.

Particle chemical composition affects aerosol optical and physical properties in ways important for the fate, transport, and impact of atmospheric particulate matter. For example, hygroscopic constituents take up water to increase the physical size of a particle, which can alter the extinction properties and atmospheric lifetime. At the collocated AERosol RObotic NETwork (AERONET) and Interagency Monitoring of PROtected Visual Environments (IMPROVE) network monitoring stations in rural Bondville, Illinois, we employ a novel cloudiness determination method to compare measured aerosol physicochemical properties on predominantly cloudy and clear sky days from 2010 to 2019. On cloudy days, aerosol optical depth (AOD) is significantly higher than on clear sky days in all seasons. Measured Ångström exponents are significantly smaller on cloudy days, indicating physically larger average particle size for the sampled populations in all seasons except winter. Mass concentrations of fine particulate matter that include estimates of aerosol liquid water (ALW) are higher on cloudy days in all seasons but winter. More ALW on cloudy days is consistent with larger particle sizes inferred from Ångström exponent measurements. Aerosol chemical composition that affects hygroscopicity plays a determining impact on cloudy versus clear sky differences in AOD, Ångström exponents, and ALW. This work highlights the need for simultaneous collocated, high-time-resolution measurements of both aerosol chemical and physical properties, in particular at cloudy times when quantitative understanding of tropospheric composition is most uncertain.

Resistant Maltodextrin Consumption in a Double-Blind, Randomized, Crossover Clinical Trial Induces Specific Changes in Potentially Beneficial Gut Bacteria.

Background: We have previously reported that the addition of resistant maltodextrin (RMD), a fermentable functional fiber, to the diet increases fecal weight as well as the amount of fecal bifidobacteria. Here, we report on the targeted analysis of changes in potentially beneficial gut bacteria associated with the intervention. Objective: The primary objective of this study was to determine the effect of adding 0, 15 and 25 g RMD to the diets of healthy free-living adults on potentially beneficial gut bacteria. Methods: We expanded on our previously reported microbiota analysis in a double-blind, placebo-controlled feeding study (NCT02733263) by performing additional qPCR analyses targeting fecal lactic acid bacteria (LAB), Akkermansia muciniphila, Faecalibacterium prausnitzii and Fusicatenibacter saccharivorans in samples from 49 participants. Results: RMD resulted in an approximately two-fold increase in fecal Fusicatenibacter saccharivorans (p = 0.024 for 15 g/day RMD and p = 0.017 for 25 g/day RMD). For Akkermansia muciniphila and Faecalibacterium prausnitzii, we obtained borderline evidence that showed increased amounts in participants that had low baseline levels of these bacteria (p < 0.1 for 25 g/day RMD). We did not detect any effects of RMD on LAB. Conclusions: RMD supplementation in healthy individuals increases Fusicatenibacter saccharivorans. Albeit to a lesser extent, RMD at the higher intake level may also increase Akkermansia muciniphila and Faecalibacterium prausnitzii in individuals with low baseline levels of those two species. Potential benefits associated with these microbiota changes remain to be established in studies with quantifiable health-related endpoints.

Validation of a novel quality of life questionnaire: the Digestion-associated Quality of Life Questionnaire (DQLQ).

BACKGROUND: Few health-related quality of life (QOL) questionnaires are designed specifically for healthy populations and are specific to gastrointestinal (GI) symptoms even though healthy individuals may frequently experience gas, bloating, constipation, diarrhea, and abdominal pain. The purpose of this study was to develop and validate a tool that could assess the impact of GI symptoms on digestion-associated QOL in otherwise healthy individuals. METHODS: After a review of current literature and with input from experienced GI researchers, a 24-item questionnaire was created. The questionnaire was reduced to 9 items with input from focus groups comprised of healthy adults experiencing GI-related symptoms and through variability analysis. The Digestion-associated QOL Questionnaire (DQLQ) was designed to be sensitive to the physical and mental well-being changes that may occur due to GI symptoms. The DQLQ was assessed for internal consistency reliability (Cronbach's alpha; McDonald's omega), test-retest reliability (intraclass correlation coefficient, ICC), and construct validity (Pearson correlations) in a study with healthy, academically stressed, undergraduate students. Convergent validity was evaluated by correlating the DQLQ with gastrointestinal symptom rating scale (GSRS) scores. Divergent validity was assessed by correlating DQLQ scores with stress scores, and bowel satisfaction scores. RESULTS: A total of 594 students (age 18-30 years) completed the DQLQ. Internal consistency reliability was favorable (n = 594; α = 0.84, ω = 0.84). A high level of agreement and correlation between DQLQ scores was found with the test-retest reliability analysis (n = 273; ICC = 0.89). The questionnaire was shown to have good convergent validity through correlation with the GSRS (n = 594; r = 0.54). Divergent validity was also shown to be appropriate by correlating DQLQ scores with stress (n = 592; r = 0.13, p < 0.005), and bowel satisfaction (n = 592; r = 0.18, p < 0.001) scores. CONCLUSION: The DQLQ is a reliable and valid questionnaire for assessing digestion-associated QOL in healthy individuals.

In healthy adults, resistant maltodextrin produces a greater change in fecal bifidobacteria counts and increases stool wet weight: a double-blind, randomized, controlled crossover study.

Dietary fiber stimulates the growth of potentially beneficial bacteria (eg, bifidobacteria), yet most Americans do not meet daily fiber recommendations. Resistant maltodextrin (RMD), a fermentable functional fiber, may help individuals meet total fiber recommendations and potentially increase bifidobacteria. It was hypothesized that fecal bifidobacteria counts/ng fecal DNA would increase after adding 25 g RMD to inadequate fiber diets of healthy adults. In this double-blind, controlled crossover study, 51 participants (26.3 ± 6.8 years, mean ± SD) were randomized to consume 0, 15, and 25 g RMD daily for 3 weeks followed by a 2-week washout. Participants collected all stools for 2 days at weeks 0 and 3 of each intervention for stool wet weight (WW) measurements and fecal bifidobacteria counts. Weekly 24-hour dietary recalls assessed total fiber intake. Only 25 g RMD resulted in a change (final minus baseline) in bifidobacteria that was significant compared with 0 g (0.17 ± 0.09 vs -0.17 ± 0.09 log10[counts], respectively, mean ± SEM, P = .008). Stool WW increased only with 25 g (150 ± 11 vs baseline 121±11 g/d; P = .011). Mean daily total fiber intake (including RMD) was significantly higher (both P< .001) with 15 g (17.8 ± 0.6 g/1000 kcal or 4184 kJ) and 25 g (25.3 ± 1.1 g/1000 kcal) compared with 0 g RMD (8.4±0.4 g/1000 kcal). Mean daily total fiber intakes exceeded recommendations (14 g/1000 kcal) with 15 and 25 g of RMD, and 25 g RMD increased fecal bifidobacteria counts and stool WW, suggesting health benefits from increasing total fiber intake.

Probiotics (Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and Bifidobacterium longum MM-2) improve rhinoconjunctivitis-specific quality of life in individuals with seasonal allergies: a double-blind, placebo-controlled, randomized trial.

Background: Rhinoconjunctivitis-specific quality of life is often reduced during seasonal allergies. The Mini Rhinoconjunctivitis Quality of Life Questionnaire (MRQLQ) is a validated tool used to measure quality of life in people experiencing allergies (0 = not troubled to 6 = extremely troubled). Probiotics may improve quality of life during allergy season by increasing the percentage of regulatory T cells (Tregs) and inducing tolerance.Objective: The objective of this study was to determine whether consuming Lactobacillus gasseri KS-13, Bifidobacterium bifidum G9-1, and B. longum MM-2 compared with placebo would result in beneficial effects on MRQLQ scores throughout allergy season in individuals who typically experience seasonal allergies. Secondary outcomes included changes in immune markers as part of a potential mechanism for changes in MRQLQ scores.Design: In this double-blind, placebo-controlled, parallel, randomized clinical trial, 173 participants (mean ± SEM: age 27 ± 1 y) who self-identified as having seasonal allergies received either a probiotic (2 capsules/d, 1.5 billion colony-forming units/capsule) or placebo during spring allergy season for 8 wk. MRQLQ scores were collected weekly throughout the study. Fasting blood samples were taken from a subgroup (placebo, n = 37; probiotic, n = 35) at baseline and week 6 (predicted peak of pollen) to determine serum immunoglobulin (Ig) E concentrations and Treg percentages.Results: The probiotic group reported an improvement in the MRQLQ global score from baseline to pollen peak (-0.68 ± 0.13) when compared with the placebo group (-0.19 ± 0.14; P = 0.0092). Both serum total IgE and the percentage of Tregs increased from baseline to week 6, but changes were not different between groups.Conclusions: This combination probiotic improved rhinoconjunctivitis-specific quality of life during allergy season for healthy individuals with self-reported seasonal allergies; however, the associated mechanism is still unclear. This trial was registered at clinicaltrials.gov as NCT02349711.

Diet quality improves for parents and children when almonds are incorporated into their daily diet: a randomized, crossover study.

The health benefits of nuts may, in part, be due to the fiber that provides substrate for the maintenance of a healthy and diverse microbiota. We hypothesized that consuming almonds would benefit immune status through improving diet quality and modulation of microbiota composition in parents and their children, while improving gastrointestinal function. In a crossover trial, 29 parents (35 ± 0.6 years) and their children (n = 29; 4 ± 0.2 years; pairs) consumed 1.5 and 0.5 oz, respectively, of almonds and/or almond butter or control (no almonds) for 3 weeks followed by 4-week washouts. Parents completed daily questionnaires of stool frequency and compliance with nut intake. The Gastrointestinal Symptom Response Scale was administered weekly. Participants provided stools for microbiota analysis and saliva for secretory immunoglobulin A. Serum antioxidant/proinflammatory balance was determined in parents. From weekly dietary recalls (Automated Self-Administered 24-Hour Dietary Recall), nutrient and energy intake were assessed and Healthy Eating Index-2010 scores were calculated. Consuming almonds increased total Healthy Eating Index score from 53.7 ± 1.8 to 61.4 ± 1.4 (parents) and 53.7 ± 2.6 to 61.4 ± 2.2 (children; P < .001). Minimal changes in gastrointestinal symptoms and no change in stool frequency were noted with the almond intervention. Microbiota was stable at the phylum and family level, but genus-level changes occurred with nut intake, especially in children. No differences were observed for immune markers. Although higher intakes of almonds or longer interventions may be needed to demonstrate effects on immune status, a moderate intake of almonds improves diet quality in adults and their young children and modulates microbiota composition.