Panel 2: ATP/CTP Experience Report & New Ideas In Flight Education

Provider and employer reports on current results, compliance success, affiliations/partnerships meeting FOQ ATP/CTP requirements. FAA Adams Collegiate & Flight Academy Educators Byrnes (ERAU), Morrison (CAE), Hibler (FSI) Employers: Airlines Greubel (ExpressJet), Haugaard (Horizon Air), Buyer (United), Dee (Republic), Winter (JetBlue), Panhans (Allegiant) New Idea in U.S. Flight Education; JetBlue Gateway 7 Program (G7) Winte

Are Recent Arctic Ozone Losses Caused by Increasing Greenhouse Gases?

It has been suggested that the Arctic ozone losses observed in recent years might be a manifestation of climate change due to increasing greenhouse gases. We here offer evidence to the contrary, by focusing on the volume of polar stratospheric clouds (Vpsc), a convenient proxy for polar ozone loss whose simplicity allows for easily reproducible results. First, we analyze the time series of Vpsc in three reanalysis data sets and find no statistically significant trends in Vpsc–nor changes in their probability density functions–over the period 1979–2011. Second, we analyze Vpsc in a stratosphere-resolving chemistry-climate model forced uniquely with increasing greenhouse gases following the A1B scenario: here too, we find no significant changes in Vpsc over the entire 21st century. Taken together, these results strongly suggest that the sporadic high ozone losses in recent years have not been caused by increasing greenhouse gases

Deep short-read sequencing of chromosome 17 from the mouse strains A/J and CAST/Ei identifies significant germline variation and candidate genes that regulate liver triglyceride levels

Methods for accurate identification of nucleotide and structural variation using de novo short read sequencing of mouse chromosomes are described

RGDS peptides immobilized on titanium alloy stimulate bone cell attachment, differentiation and confer resistance to apoptosis

A major cause of implant failure in skeletal tissues is failure of osseointegration, often due to lack of adhesion of cells to the titanium (Ti) alloy interface. Since arginine- glycine-aspartic acid (RGD)-containing peptides have been shown to regulate osteoblast adhesion, we tested the hypothesis that, bound to a Ti surface, these peptides would promote osteoblasts differentiation, while at the same time inhibit apoptosis. RGDS and RGES (control) peptides were covalently linked to Ti discs using an APTS linker. While the grafting of both RGDS and RGES significantly increased Ti surface roughness, contact angle analysis showed that APTS significantly increased the surface hydrophobicity; when the peptides were tethered to Ti, this was reduced. To evaluate attachment, MC3T3-E1 osteoblast cells were grown on these discs. Significantly more cells attached to the Ti-grafted RGDS then the Ti-grafted RGES control. Furthermore, expression of the osteoblasts phenotype was significantly enhanced on the Ti-grafted RGDS surface. When cells attached to the Ti-grafted RGDS were challenged with staurosporine, an apoptogen, there was significant inhibition of apoptosis; in contrast, osteoblasts adherent to the Ti-grafted RGES were killed. It is concluded that RGD-containing peptides covalently bonded to Ti promotes osteoblasts attachment and survival with minimal changes to the surface of the alloy. Therefore, such modifications to Ti would have the potential to promote osseointegration in vivo

Interruptions in HIV Prevention and Treatment During the COVID-19 Pandemic: A Cross-Sectional Study of Transgender and Gender Nonbinary Adults in the United States

Background: Transgender and gender nonbinary (TNB) people have been disproportionately affected by HIV and the COVID-19 pandemic. This study explored the prevalence of HIV prevention and treatment (HPT) interruptions during the pandemic and identified factors associated with these interruptions. Setting: Data were drawn from LITE Connect, a US-based, nationwide, online, self-administered survey designed to examine the experiences of TNB adults during the COVID-19 pandemic. A convenience sample of 2134 participants were recruited between June 14, 2021, and May 1, 2022. Methods: The analytic sample was restricted to participants taking antiretroviral medications to prevent or treat HIV before the onset of the pandemic (n = 153). We calculated descriptive statistics as well as Pearson χ2 bivariate tests and multivariable models to identify factors associated with HPT interruptions during the pandemic. Results: Thirty-nine percent of participants experienced an HPT interruption. We found a lower odds of HPT interruptions among participants living with HIV [adjusted odds ratios (aOR) 0.45; 95% Confidence Intervals (CI): 0.22, 0.92; P = 0.02] and essential workers [aOR 0.49; 95% CI: 0.23, 1.0; P = 0.06] and higher odds among people with chronic mental health conditions [aOR 2.6; 95% CI: 1.1, 6.2; P = 0.03]. When sex and education were included, we found a lower odds of interruptions among people with higher education. CI widened, but the magnitude and direction of effects did not change for the other variables. Conclusions: Focused strategies to address longstanding psychosocial and structural inequities are needed to mitigate HPT treatment interruptions in TNB people and prevent similar challenges during future pandemics

The Antibacterial Activity of Honey Derived from Australian Flora

Chronic wound infections and antibiotic resistance are driving interest in antimicrobial treatments that have generally been considered complementary, including antimicrobially active honey. Australia has unique native flora and produces honey with a wide range of different physicochemical properties. In this study we surveyed 477 honey samples, derived from native and exotic plants from various regions of Australia, for their antibacterial activity using an established screening protocol. A level of activity considered potentially therapeutically useful was found in 274 (57%) of the honey samples, with exceptional activity seen in samples derived from marri (Corymbia calophylla), jarrah (Eucalyptus marginata) and jellybush (Leptospermum polygalifolium). In most cases the antibacterial activity was attributable to hydrogen peroxide produced by the bee-derived enzyme glucose oxidase. Non-hydrogen peroxide activity was detected in 80 (16.8%) samples, and was most consistently seen in honey produced from Leptospermum spp. Testing over time found the hydrogen peroxide-dependent activity in honey decreased, in some cases by 100%, and this activity was more stable at 4°C than at 25°C. In contrast, the non-hydrogen peroxide activity of Leptospermum honey samples increased, and this was greatest in samples stored at 25°C. The stability of non-peroxide activity from other honeys was more variable, suggesting this activity may have a different cause. We conclude that many Australian honeys have clinical potential, and that further studies into the composition and stability of their active constituents are warranted

The onset and cessation of seasonal rainfall over Africa

Variation in the seasonal cycle of African rainfall is of key importance for agriculture. Here, an objective method of determining the timing of onset and cessation is, for the first time, extended to the whole of Africa. The method is applied to five observational datasets and the ERA-Interim reanalysis. Compatibility with known physical drivers of African rainfall, consistency with indigenous methods, and generally strong agreement between satellite-based rainfall datasets confirm the method is capturing the correct seasonal progression of African rainfall. The biannual rainfall regime is correctly identified over the coastal region of Ghana and the Ivory Coast. However, the ERA-Interim reanalysis exhibits timing biases over areas with two rainy seasons, and both ERA-Interim and the ARCv2 observational dataset exhibit some inconsistent deviations over West Africa. The method can be used to analyze both seasonal - interannual variability and long-term change. Over East Africa, we find that failure of the rains and subsequent humanitarian disaster is associated with shorter as well as weaker rainy seasons, e.g. on average the long rains were 11 days shorter in 2011. Cessation of the short rains over this region is 7 days later in El Niño and 5 days earlier in La Niña years with only a small change in onset date. The methodology described in this paper is applicable to multiple datasets and to large regions, including those that experience multiple rainy seasons. As such, it provides a means for investigating variability and change in the seasonal cycle over the whole of Africa

Skeletal muscle stem cells express anti-apoptotic ErbB receptors during activation from quiescence

To be effective for tissue repair, satellite cells (the stem cells of adult muscle) must survive the initial activation from quiescence. Using an in vitro model of satellite cell activation, we show that erbB1, erbB2 and erbB3, members of the EGF receptor tyrosine kinase family, appear on satellite cells within 6 h of activation. We show that signalling via erbB2 provides an anti-apoptotic survival mechanism for satellite cells during the first 24 h, as they progress to a proliferative state. Inhibition of erbB2 signalling with AG825 reduced satellite cell numbers, concomitant with elevated caspase-8 activation and TUNEL labelling of apoptotic satellite cells. In serum-free conditions, satellite cell apoptosis could be largely prevented by a mixture of erbB1, erbB3 and erbB4 ligand growth factors, but not by neuregulin alone (erbB3/erbB4 ligand). Furthermore, using inhibitors specific to discrete intracellular signalling pathways, we identify MEK as a pro-apoptotic mediator, and the erbB-regulated factor STAT3 as an anti-apoptotic mediator during satellite cell activation. These results implicate erbB2 signalling in the preservation of a full compliment of satellite cells as they activate in the context of a damaged muscle

The Impact of Bias Correction and Model Selection on Passing Temperature Thresholds

Knowledge of when specific global or local temperature levels are reached is important for decision makers in that it provides a time frame over which adaptation strategies for temperature‐related climate impacts need to be put in place. The time frame varies depending on the adaptation strategy but can range from a few years to the order of decades. Climate models, however, show a high degree of uncertainty in the timing of passing specific warming levels, limiting their use in adaptation policy development. This study examines the impact of two approaches, which may reduce the uncertainty in modeled timing of reaching specific warming levels. First, the use of different performance metrics to preferentially weight model ensembles and second, the application of four bias correction approaches. Using the Coupled Model Intercomparison Project phase 5 simulations of the Representative Concentration Pathways, our results show that both selecting models based on performance and bias correcting model data reduce the spread in timing of specific warming levels reached in the first half of the century by up to 50% in some regions. This implies the potential of these approaches to support adaptation planning