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Background The specific cause(s) of asthma development must be identified in order to prevent this disease. Objective Our hypothesis was that specific mold exposures are associated with childhood asthma development. Methods Infants were identified from birth certificates. Dust samples were collected from 289 homes when the infants were age eight months. Samples were analyzed for concentrations of 36 molds that comprise the Environmental Relative Moldiness Index (ERMI) and endotoxin, house dust mite, cat, dog, and cockroach allergens. Children were evaluated at age seven for asthma based on reported symptoms and objective measures of lung function. Host, environmental exposures and home characteristics evaluated included history of parental asthma, race, gender, upper and lower respiratory symptoms, season of birth, family income, cigarette smoke exposure, air conditioning, dehumidifier, carpeting, age of home, and visible mold at age one and child positive skin prick test (SPT) to aeroallergens and molds at age seven. Results Asthma was diagnosed in 24% of the children at age seven. A statistically significant increase in asthma risk at age seven was associated with high ERMI levels in the child’s home in infancy (adjusted risk ratio (aRR) for a 10-unit increase in ERMI = 1.8, 95% CI=1.5, 2.2). The summation of levels of three mold species, Aspergillus ochraceus, Aspergillus unguis, and Penicillium variabile was significantly associated with asthma (aRR = 2.2, 95% CI=1.8, 2.7). Conclusion In this birth cohort study, exposure during infancy to three mold species common to water-damaged buildings was associated with childhood asthma at age seven.

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Transition metal nitrogen carbon based single‐atom catalysts (SACs) have exhibited superior activity and selectivity for CO2 electroreduction to CO. A favorable local nitrogen coordination environment is key to construct efficient metal‐N moieties. Here, a facile plasma‐assisted and nitrogen vacancy (NV) induced coordinative reconstruction strategy is reported for this purpose. Under continuous plasma striking, the preformed pentagon pyrrolic N‐defects around Ni sites can be transformed to a stable pyridinic N dominant Ni‐N2 coordination structure with promoted kinetics toward the CO2‐to‐CO conversion. Both the CO selectivity and productivity increase markedly after the reconstruction, reaching a high CO Faradaic efficiency of 96% at mild overpotential of 590 mV and a large CO current density of 33 mA cm‐2 at 890 mV. X‐ray adsorption spectroscopy and density functional theory (DFT) calculations reveal this defective local N environment decreases the restraint on central Ni atoms and provides enough space to facilitate the adsorption and activation of CO2 molecule, leading to a reduced energy barrier for CO2 reduction.

A boron (B) center, which has an electronic structure mimicking the filled and empty d orbitals in transition metals, can effectively activate the triple bond in N 2 so as to catalyze the nitrogen reduction reaction (NRR). Here, by means of density functional theory, we have systematically investigated the catalytic performance of a single B atom decorated on two-dimensional transition metal carbides (MXenes). The B-doped Mo 2 CO 2 and W 2 CO 2 MXenes exhibit outstanding catalytic activity and selectivity with limiting potentials of −0.20 and −0.24 V, respectively. Importantly, we have found that, although a high tendency of B-to-adsorbate electron donation can promote the hydrogenation of *N 2 to *N 2 H, it would also severely hamper the *NH 2 to *NH 3 conversion due to the strong B−N bonding. Such an electron-donation effect can be reasonably tuned by the transition metal in the MXene substrate, which enables us to achieve optimized catalytic performance with a certain moderate degree of electron donation.

These differences in nutrient intakes, physical activity and body size of Chinese living on two different continents suggest possible explanations for observed differences in chronic disease rates in the two populations.

The early environment, especially the age when parents introduce toothbrushing to their children, can be an important factor to prevent childhood dental caries.

This is the first controlled trial demonstrating intranasal capsaicin, when used continuously over 2 weeks, rapidly and safely improves symptoms in rhinitis subjects with a significant NAR component.