Ozone Contamination in Aircraft Cabins. Appendix A: Ozone toxicity

The recommendation that at various altitudes the amount of air with which ozone has mixed changes, thus changing the volume per volume relationship is discussed. The biological effects of ozone on human health and the amount of ozone necessary to produce symptoms were investigated

Microbial Iron(II) Oxidation in Littoral Freshwater Lake Sediment: The Potential for Competition between Phototrophic vs. Nitrate-Reducing Iron(II)-Oxidizers

The distribution of neutrophilic microbial iron oxidation is mainly determined by local gradients of oxygen, light, nitrate and ferrous iron. In the anoxic top part of littoral freshwater lake sediment, nitrate-reducing and phototrophic Fe(II)-oxidizers compete for the same e− donor; reduced iron. It is not yet understood how these microbes co-exist in the sediment and what role they play in the Fe cycle. We show that both metabolic types of anaerobic Fe(II)-oxidizing microorganisms are present in the same sediment layer directly beneath the oxic-anoxic sediment interface. The photoferrotrophic most probable number counted 3.4·105 cells·g−1 and the autotrophic and mixotrophic nitrate-reducing Fe(II)-oxidizers totaled 1.8·104 and 4.5·104 cells·g−1 dry weight sediment, respectively. To distinguish between the two microbial Fe(II) oxidation processes and assess their individual contribution to the sedimentary Fe cycle, littoral lake sediment was incubated in microcosm experiments. Nitrate-reducing Fe(II)-oxidizing bacteria exhibited a higher maximum Fe(II) oxidation rate per cell, in both pure cultures and microcosms, than photoferrotrophs. In microcosms, photoferrotrophs instantly started oxidizing Fe(II), whilst nitrate-reducing Fe(II)-oxidizers showed a significant lag-phase during which they probably use organics as e− donor before initiating Fe(II) oxidation. This suggests that they will be outcompeted by phototrophic Fe(II)-oxidizers during optimal light conditions; as phototrophs deplete Fe(II) before nitrate-reducing Fe(II)-oxidizers start Fe(II) oxidation. Thus, the co-existence of the two anaerobic Fe(II)-oxidizers may be possible due to a niche space separation in time by the day-night cycle, where nitrate-reducing Fe(II)-oxidizers oxidize Fe(II) during darkness and phototrophs play a dominant role in Fe(II) oxidation during daylight. Furthermore, metabolic flexibility of Fe(II)-oxidizing microbes may play a paramount role in the conservation of the sedimentary Fe cycle

Pooled Analysis of Individually Fed Finishing Trials

A pooled analysis of 21 finishing trials (2002–2016; 1530 animals) with cattle individually fed in Calan gate barns was conducted. Mixed model regression analysis following random coefficient methodology was used to evaluate relationships between performance variables and carcass characteristics. Gain had a greater effect on efficiency (R2 = 0.72) compared to intake (R2 = 0.02). The relationship between gain and efficiency was cubic, while intake had a quadratic relationship. The cubic response of gain relative to efficiency was continually increasing with relatively slight curves in the line heavily influenced by points that lay on the ends of the data. Efficiency also had cubic relationships with fat thickness and marbling of carcasses; however, the regressions had low R2 values of 0.01. There was a significant relationship between efficiency and fat thickness and marbling, but the variation around the trend line was high. Efficiency alone is a poor predictor of fat thickness and marbling

IL-17A produced by αβ T cells drives airway hyper-responsiveness in mice and enhances mouse and human airway smooth muscle contraction.

Emerging evidence suggests that the T helper 17 (T(H)17) subset of αβ T cells contributes to the development of allergic asthma. In this study, we found that mice lacking the αvβ8 integrin on dendritic cells did not generate T(H)17 cells in the lung and were protected from airway hyper-responsiveness in response to house dust mite and ovalbumin sensitization and challenge. Because loss of T(H)17 cells inhibited airway narrowing without any obvious effects on airway inflammation or epithelial morphology, we examined the direct effects of T(H)17 cytokines on mouse and human airway smooth muscle function. Interleukin-17A (IL-17A), but not IL-17F or IL-22, enhanced contractile force generation of airway smooth muscle through an IL-17 receptor A (IL-17RA)-IL-17RC, nuclear factor κ light-chain enhancer of activated B cells (NF-κB)-ras homolog gene family, member A (RhoA)-Rho-associated coiled-coil containing protein kinase 2 (ROCK2) signaling cascade. Mice lacking integrin αvβ8 on dendritic cells showed impaired activation of this pathway after ovalbumin sensitization and challenge, and the diminished contraction of the tracheal rings in these mice was reversed by IL-17A. These data indicate that the IL-17A produced by T(H)17 cells contributes to allergen-induced airway hyper-responsiveness through direct effects on airway smooth muscle

Acupressure to Reduce Treatment-Related Symptoms for Children With Cancer and Recipients of Hematopoietic Stem Cell Transplant: Protocol for a Randomized Controlled Trial.

BackgroundWe describe the study design and protocol of a pragmatic randomized controlled trial (RCT) Acupressure for Children in Treatment for a Childhood Cancer (ACT-CC).ObjectiveTo describe the feasibility and effectiveness of an acupressure intervention to decrease treatment-related symptoms in children in treatment for cancer or recipients of a chemotherapy-based hematopoietic stem cell transplant (HSCT).DesignTwo-armed RCTs with enrollment of 5 to 30 study days.SettingTwo pediatric teaching hospitals.PatientsEighty-five children receiving cancer treatment or a chemotherapy-based HSCT each with 1 parent or caregiver.InterventionPatients are randomized 1:1 to receive either usual care plus daily professional acupressure and caregiver delivered acupressure versus usual care alone for symptom management. Participants receive up to 20 professional treatments.Main outcomeA composite nausea/vomiting measure for the child.Secondary outcomesChild's nausea, vomiting, pain, fatigue, depression, anxiety, and positive affect.Parent outcomesDepression, anxiety, posttraumatic stress symptoms, caregiver self-efficacy, and positive affect. Feasibility of delivering the semistandardized intervention will be described. Linear mixed models will be used to compare outcomes between arms in children and parents, allowing for variability in diagnosis, treatment, and age.DiscussionTrial results could help childhood cancer and HSCT treatment centers decide about the regular inclusion of trained acupressure providers to support symptom management

In Solidarity

This edition of Next Page is a departure from our usual question and answer format with a featured campus reader. Instead, we asked speakers who participated in the College’s recent Student Solidarity Rally (March 1, 2017) to recommend readings that might further our understanding of the topics on which they spoke

Impact of Shade in Beef Feedyards on Performance, Body Temperature, and Heat Stress Measures

A study using crossbred steers was conducted at a commercial feedyard to determine the effects of pen shades on cattle performance, body temperature, and cattle activity. Two heat events (Event 1 and Event 2) and one cool event were defined for the feeding period. No significant differences were observed for average daily gain, dry matter intake, feed to gain, or carcass characteristics at the end of the trial. During Event 1, cattle in pens with shade had lower panting scores than cattle in open pens. During Event 2, cattle in shade pens had greater dry matter intake, lower panting scores, and lower ear temperature. Throughout the entire feeding period, cattle in open pens had greater ear temperature and panting scores than cattle in shaded pens while movement was not different between treatments. Using shades for feedyard cattle did not impact performance, but did improve some measures of heat stress

A Sweeping Jet Application on a High Reynolds Number Semispan Supercritical Wing Configuration

The FAST-MAC circulation control model was modified to test an array of unsteady sweeping-jet actuators at realistic flight Reynolds numbers in the National Transonic Facility at the NASA Langley Research Center. Two types of sweeping jet actuators were fabricated using rapid prototype techniques, and directed over a 15% chord simple-hinged flap. The model was configured for low-speed high-lift testing with flap deflections of 30 deg and 60 deg, and a transonic cruise configuration having a 0 deg flap deflection. For the 30 deg flap high-lift configuration, the sweeping jets achieved comparable lift performance in the separation control regime, while reducing the mass flow by 54% as compared to steady blowing. The sweeping jets however were not effective for the 60 deg flap. For the transonic cruise configuration, the sweeping jets reduced the drag by 3.3% at an off-design condition. The drag reduction for the design lift coefficient for the sweeping jets offer is only half the drag reduction shown for the steady blowing case (6.5%), but accomplished this with a 74% reduction in mass flow

Meta-Analysis Reveals Challenges and Gaps for Genome-to-Phenome Research Underpinning Plant Drought Response

Severe drought conditions and extreme weather events are increasing worldwide with climate change, threatening the persistence of native plant communities and ecosystems. Many studies have investigated the genomic basis of plant responses to drought. However, the extent of this research throughout the plant kingdom is unclear, particularly among species critical for the sustainability of natural ecosystems. This study aimed to broaden our understanding of genome-to-phenome (G2P) connections in drought-stressed plants and identify focal taxa for future research. Bioinformatics pipelines were developed to mine and link information from databases and abstracts from 7730 publications. This approach identified 1634 genes involved in drought responses among 497 plant taxa. Most (83.30%) of these species have been classified for human use, and most G2P interactions have been described within model organisms or crop species. Our analysis identifies several gaps in G2P research literature and database connectivity, with 21% of abstracts being linked to gene and taxonomy data in NCBI. Abstract text mining was more successful at identifying potential G2P pathways, with 34% of abstracts containing gene, taxa, and phenotype information. Expanding G2P studies to include non-model plants, especially those that are adapted to drought stress, will help advance our understanding of drought responsive G2P pathways

Childhood sleep health and epigenetic age acceleration in late adolescence: Cross-sectional and longitudinal analyses

Aim: Investigate if childhood measures of sleep health are associated with epigenetic age acceleration in late adolescence. Methods: Parent-reported sleep trajectories from age 5 to 17, self-reported sleep problems at age 17, and six measures of epigenetic age acceleration at age 17 were studied in 1192 young Australians from the Raine Study Gen2. Results: There was no evidence for a relationship between the parent-reported sleep trajectories and epigenetic age acceleration (p ≥ 0.17). There was a positive cross-sectional relationship between self-reported sleep problem score and intrinsic epigenetic age acceleration at age 17 (b = 0.14, p = 0.04), which was attenuated after controlling for depressive symptom score at the same age (b = 0.08, p = 0.34). Follow-up analyses suggested this finding may represent greater overtiredness and intrinsic epigenetic age acceleration in adolescents with higher depressive symptoms. Conclusion: There was no evidence for a relationship between self- or parent-reported sleep health and epigenetic age acceleration in late adolescence after adjusting for depressive symptoms. Mental health should be considered as a potential confounding variable in future research on sleep and epigenetic age acceleration, particularly if subjective measures of sleep are used