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Photochemically produced SO2 in the atmosphere of WASP-39b
Get PDFPhotochemistry is a fundamental process of planetary atmospheres that regulates the atmospheric composition and stability1. However, no unambiguous photochemical products have been detected in exoplanet atmospheres so far. Recent observations from the JWST Transiting Exoplanet Community Early Release Science Program2,3 found a spectral absorption feature at 4.05 μm arising from sulfur dioxide (SO2) in the atmosphere of WASP-39b. WASP-39b is a 1.27-Jupiter-radii, Saturn-mass (0.28 MJ) gas giant exoplanet orbiting a Sun-like star with an equilibrium temperature of around 1,100 K (ref. 4). The most plausible way of generating SO2 in such an atmosphere is through photochemical processes5,6. Here we show that the SO2 distribution computed by a suite of photochemical models robustly explains the 4.05-μm spectral feature identified by JWST transmission observations7 with NIRSpec PRISM (2.7σ)8 and G395H (4.5σ)9. SO2 is produced by successive oxidation of sulfur radicals freed when hydrogen sulfide (H2S) is destroyed. The sensitivity of the SO2 feature to the enrichment of the atmosphere by heavy elements (metallicity) suggests that it can be used as a tracer of atmospheric properties, with WASP-39b exhibiting an inferred metallicity of about 10× solar. We further point out that SO2 also shows observable features at ultraviolet and thermal infrared wavelengths not available from the existing observations
Environment and Planning F: Special issue on Indigenous Research Sovereignty
No full textThis is the 2023 special issue about Indigenous Research Sovereignty published in the journal Environment and Planning F: Philosophy, Theory, Models, Methods, and Practice, volume 2, numbers 1-2. It was edited by Jay T. Johnson, Joseph P. Brewer II, Melissa K. Nelson, Mark H. Palmer and Renee Pualani Louis
The Cultural Responsiveness of the Communicative and Task-Based Instructional Approaches to African English Language Learners in a College ESL Classroom: A Qualitative Case Study
Get PDFThis presentation was given at the Innovation in Language Learning International Conference in Florence, Italy on November 9-10, 2023.In the United States school education system, there are students who are identified as English Language Learners (ELLs). ELLs are multilingual students who speak any other language apart from English at home. While majority of the ELLs are born in the United States, a few of them are immigrants from different parts of the world who later joined the US school system (Zong and Batalova, 2015), and this study focuses on the latter student populations at a college level. Various second language teaching approaches are often utilized by language teachers to make their classroom instructions effective. Lightbown & Spada (2013) state communicative, task-based and content-based instructions, which appear to be commonly used when compared to the grammar translation and audiolingual approaches. The former instructions provide a ground for students to interact, converse, and communicate using the target language, and the students are expected to actively engage in the class discussions and interactions while the teacher facilitates them (Lightbown & Spada, 2013). However, little is known how culturally responsive the communicative and task-based instructions are to African ELLs in a college English as a Second Language (ESL) classroom in the Midwest. In order to address this gab, five African ELLs were selected based on convenience sampling and data were gathered through semi-structured interview and focus-group discussion. After analyzing the data through Miles and Huberman’s (1994) qualitative data analysis procedures, the following findings were reported. The cultural identity of the African ELLs did not seem to align with the principles of communicative and task-based instructional approaches, as the ELLs were raised to speak less but to listen more, avoid eye contact, and keep their head down when conversing as a sign of respect to the teachers. These elements of African cultural identity appeared to inhibit the ELLs from participating freely and actively in the English conversations, interactions, and group works in a college ESL classroom in the Midwest, United States. The study concludes that the communicative and task-based instructions should be culturally responsive to meet the unique needs of the African ELLs in a college ESL classroom
Liver-expressed antimicrobial peptide 2 elevation contributes to age-associated cognitive decline
Get PDFElderly individuals frequently report cognitive decline, while various studies indicate hippocampal functional declines with advancing age. Hippocampal function is influenced by ghrelin through hippocampus-expressed growth hormone secretagogue receptor (GHSR). Liver-expressed antimicrobial peptide 2 (LEAP2) is an endogenous GHSR antagonist that attenuates ghrelin signaling. Here, we measured plasma ghrelin and LEAP2 levels in a cohort of cognitively normal individuals older than 60 and found that LEAP2 increased with age while ghrelin (also referred to in literature as “acyl-ghrelin”) marginally declined. In this cohort, plasma LEAP2/ghrelin molar ratios were inversely associated with Mini-Mental State Examination scores. Studies in mice showed an age-dependent inverse relationship between plasma LEAP2/ghrelin molar ratio and hippocampal lesions. In aged mice, restoration of the LEAP2/ghrelin balance to youth-associated levels with lentiviral shRNA Leap2 downregulation improved cognitive performance and mitigated various age-related hippocampal deficiencies such as CA1 region synaptic loss, declines in neurogenesis, and neuroinflammation. Our data collectively suggest that LEAP2/ghrelin molar ratio elevation may adversely affect hippocampal function and, consequently, cognitive performance; thus, it may serve as a biomarker of age-related cognitive decline. Moreover, targeting LEAP2 and ghrelin in a manner that lowers the plasma LEAP2/ghrelin molar ratio could benefit cognitive performance in elderly individuals for rejuvenation of memory
High-Intensity Functional Training: Perceived Functional and Psychosocial Health-Related Outcomes from Current Participants with Mobility-Related Disabilities
Get PDFBackground: People with mobility-related disabilities (MRDs) experience many personal and environmental barriers to engagement in community-based exercise programs. We explored the experiences of adults with MRD who currently participate in high-intensity functional training (HIFT), an inclusive and accessible community-based exercise program. Methods: Thirty-eight participants completed online surveys with open-ended questions, with ten individuals also participating in semi-structured interviews via telephone with project PI. Surveys and interviews were designed to examine changes to perceived health, and the elements of HIFT that promote sustained participation. Results: Thematic analysis revealed themes related to health changes following HIFT participation including improved physical, functional, and psychosocial health outcomes. Other themes emerged within the HIFT environment that promoted adherence for participants such as accessible spaces and equipment, and inclusive HIFT sessions and competitions. Additional themes included participants’ advice for the disability and healthcare communities. The resulting themes are informed by the World Health Organization’s International Classification of Functioning, Disability, and Health. Conclusion: The findings provide initial data on the potential effects of HIFT on multiple dimensions of health outcomes and contribute to the growing literature on community-based programs that are adaptable and inclusive for people with MRD
‘Now More Than Ever, Survivors Need Us’: Essential labouring and increased precarity during COVID-19
Get PDFDuring the earliest waves of the COVID-19 pandemic, much media and public discourse focused on the effects of increasing precarity on already vulnerable populations. As in-person work added a layer of viral risk and unemployment drastically exacerbated economic precariousness, the category of ‘essential worker’ gained new prominence in these conversations. In this paper, we focus on the complicated relationship between two groups of workers depicted as marginalised and exploited to different degrees during COVID-19: trafficked persons and anti-trafficking service providers. Though media coverage did not conflate these groups, it applied a capacious understanding of precarious labour and structural inequalities that encapsulated different types of essential work. We draw on media produced by frontline anti-trafficking and sex workers’ rights organisations between March and May 2020. Even with renewed attention to macro-level harms, many publications still emphasised individualism over collectivity. This emphasis on singular organisational representatives—frontline workers—as heroic rescuers mirrored larger, normative anti-trafficking discourses. At the point at which the ‘new normal’ was nowhere in sight, COVID-19 served as a flashpoint to reconsider current intervention strategies and instead emphasise a critique of precarious labour along multiple vectors
The potter wasp genus Allorhynchium from Vietnam, with descriptions of three new species and a new country record (Hymenoptera, Vespidae, Eumeninae)
Get PDFSpecies of the potter wasp genus Allorhynchium van der Vecht (Eumeninae: Odynerini) occurring in Vietnam are presented. Seven species have been recorded from Vietnam. Of them, three species are described as new to science: Allorhynchium latum Nguyen, Tran & MT Nguyen, sp. nov., A. moerum Nguyen & AD Nguyen, sp. nov., and A. setosum Nguyen & Engel, sp. nov., and one species, A. argentatum (Fabricius, 1804), is recorded from Vietnam for the first time. An updated key to the Oriental species of the genus is presented
Formulation development and comparability studies with an aluminum-salt adjuvanted SARS-CoV-2 Spike ferritin nanoparticle vaccine antigen produced from two different cell lines (Dataset)
No full textThe development of safe and effective second-generation COVID-19 vaccines to improve affordability and storage stability requirements remains a high priority to expand global coverage. In this report, we describe formulation development and comparability studies with a self-assembled SARS-CoV-2 spike ferritin nanoparticle vaccine antigen (called DCFHP), when produced in two different cell lines and formulated with an aluminum-salt adjuvant (Alhydrogel, AH). Varying levels of phosphate buffer altered the extent and strength of antigen-adjuvant interactions, and these formulations were evaluated for their (1) in vivo performance in mice and (2) in vitro stability profiles. Unadjuvanted DCFHP produced minimal immune responses while AH-adjuvanted formulations elicited greatly enhanced pseudovirus neutralization titers independent of ~100%, ~40% or ~10% of the DCFHP antigen adsorbed to AH. These formulations differed, however, in their in vitro stability properties as determined by biophysical studies and a competitive ELISA for measuring ACE2 receptor binding of AH-bound antigen. Interestingly, after one month of 4ºC storage, small increases in antigenicity with concomitant decreases in the ability to desorb the antigen from the AH were observed. Finally, we performed a comparability assessment of DCFHP antigen produced in Expi293 and CHO cells, which displayed expected differences in their N-linked oligosaccharide profiles. Despite consisting of different DCFHP glycoforms, these two preparations were highly similar in their key quality attributes including molecular size, structural integrity, conformational stability, binding to ACE2 receptor and mouse immunogenicity profiles. Taken together, these studies support future preclinical and clinical development of an AH-adjuvanted DCFHP vaccine candidate produced in CHO cells