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  1. Replication Protein A (RPA) is single-strand DNA binding protein that plays a key role in the replication and repair of DNA. RPA is a heterotrimer made of 3 subunits – RPA1, RPA2, and RPA3. Germline pathogenic variants affectingRPA1were recently described in patients with Telomere Biology Disorders (TBD), also known as dyskeratosis congenita or short telomere syndrome. Premature telomere shortening is a hallmark of TBD and results in bone marrow failure and predisposition to hematologic malignancies. Building on the finding that somatic mutations in RPA subunit genes occur in ~1% of cancers, we hypothesized that germline RPA alterations might be enriched in human cancers. Because germlineRPA1mutations are linked to early onset TBD with predisposition to myelodysplastic syndromes, we interrogated pediatric cancer cohorts to define the prevalence and spectrum of rare/novel and putative damaging germlineRPA1,RPA2, andRPA3variants. In this study of 5,993 children with cancer, 75 (1.25%) harbored heterozygous rare (non-cancer population allele frequency (AF) < 0.1%) variants in the RPA heterotrimer genes, of which 51 cases (0.85%) had ultra-rare (AF < 0.005%) or novel variants. Compared with Genome Aggregation Database (gnomAD) non-cancer controls, there was significant enrichment of ultra-rare and novelRPA1, but notRPA2orRPA3, germline variants in our cohort (adjusted p-value < 0.05). Taken together, these findings suggest that germline putative damaging variants affectingRPA1are found in excess in children with cancer, warranting further investigation into the functional role of these variants in oncogenesis.

     
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  2. Eight semesters of qualitative data, collected over four academic years, are presented from a project that resulted in the development of a student professional learning community of high-achieving, low-income engineering and engineering technology student veterans. In the context of this project, student veterans received academic, professional, and financial support that helped them to be successful in school and to prepare them for a career in the STEM workforce. As adult learners, students in this learning community were a vital part of the curriculum development which resulted in increasing the students’ interest and buy-in. Typically, adult learners have lower levels of engagement than tradition-age students due to their non-traditional status. However, by engaging students in the development of a seminar course which served as the foundation for the student learning community, the course curriculum addressed student needs while being built on faculty expertise. Focus groups were conducted at the end of each semester to determine if students perceived the course as an effective professional development intervention. The course was comprised of various guest speaker who addressed different topics related to engineering, and the course also addressed other topics of professional development. In addition to hearing from various guest speakers, students also learned critical professional skills including how to search for an internship and/or permanent position; how to develop a cover letter, resume, and follow-up letter; how to prepare for and respond to questions during interviews; how to present themselves, how to dress, eat and hold a professional conversation at a formal meal during an interview; and how to network and follow-up after meeting people professionally. The guest speakers, veterans themselves, were excited to present to these highly motivated student veterans and to share their stories, and in the process, they inspired this next generation of engineers and engineering technologists. 
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  3. We present applications of the full-wave solver, Petra-M code for Earth magnetospheric plasma wave physics by leveraging the current effort of the radio frequency wave project. Because the Petra-M code uses the modular finite element method (MFEM) library, the boundary shapes, plasma density profiles, and realistic planetary magnetic fields can be easily adapted. In order to incorporate realistic Earth’s magnetic field into the Petra-M, we utilize the self-consistent magnetospheric flux models for compressed and stretched magnetic fields and realistic magnetospheric magnetic field geometries extracted from global MHD simulations. Using Petra-M code, we then examine ultra-low frequency (ULF) wave propagations in various magnetic field shapes. For example, left-handed polarized electromagnetic ion cyclotron waves in Earth’s dipole and compressed magnetic field are examined to consider waves in the inner and dayside outer magnetospheres, respectively. Mode-converted Alfvén wave propagation is also demonstrated in the compressed (dayside), stretched(nightside), and realistically stretched magnetic field (magnetotail). Therefore, the Petra-M code successfully demonstrates magnetospheric plasma wave propagation despite the spatial scale differences between the fusion devices (~m) and Earth’s magnetosphere (103 − 104km). 
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  5. Abstract

    The ionospheric density displays hemispheric asymmetries in the polar region due to various hemispheric differences, for example, in the offset between geographic and geomagnetic poles and in the geomagnetic field strength. Using ground‐based ionospheric measurements from Vertical Incidence Pulsed Ionospheric Radar with Dynasonde analysis at Jang Bogo Station (JBS), Antarctica and from EISCAT Svalbard Radar (ESR) where both sites are located mostly in the polar cap, we investigate the hemispheric differences in the ionospheric density between the northern and southern hemispheres for geomagnetically quiet and solar minimum condition. The results are also compared with Thermosphere Ionosphere Electrodynamic Global Circulation Model (TIEGCM) simulations. The observations show larger density and stronger diurnal and seasonal variations at JBS in the southern hemisphere than at Svalbard in the northern hemisphere. The diurnal variations of the density peak height are also observed to be much larger at JBS. In both hemispheres, the ionospheric density is significantly reduced in winter due to the limited solar production at high geographic latitudes, but TIEGCM considerably overestimates winter density, which is even larger than summer density, especially in the northern hemisphere. Also existed are the differences in the equinoctial asymmetry between the observations and the simulations: the daytime F‐region density is observed to be larger in fall than in spring in both hemispheres, but TIEGCM shows the opposite. In general, most of the observed asymmetrical density are much weaker in the model simulation, which may result from lack of proper magnetospheric forcings and neutral dynamics in the model.

     
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  6. Abstract

    Conservation funding is currently limited; cost‐effective conservation solutions are essential. We suggest that the thousands of field stations worldwide can play key roles at the frontline of biodiversity conservation and have high intrinsic value. We assessed field stations’ conservation return on investment and explored the impact of COVID‐19. We surveyed leaders of field stations across tropical regions that host primate research; 157 field stations in 56 countries responded. Respondents reported improved habitat quality and reduced hunting rates at over 80% of field stations and lower operational costs per km2than protected areas, yet half of those surveyed have less funding now than in 2019. Spatial analyses support field station presence as reducing deforestation. These “earth observatories” provide a high return on investment; we advocate for increased support of field station programs and for governments to support their vital conservation efforts by investing accordingly.

     
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    Free, publicly-accessible full text available March 4, 2025
  7. Lemur catta is the most reported illegal captive lemur. We document 286 L. catta that were held in illegal captive conditions in Madagascar. Coastal tourist destinations are “hot spots” for sightings. Many of the L. catta reported were in businesses (49%) and were perceived to be held captive for the purpose of generating income (41%). Infant/juvenile L. catta were overwhelmingly observed annually in December (41%) and may suffer high mortality rates given that they are not weaned during this month of the year. Population growth modeling suggests that known capture rates may be sustainable in all but small populations of 500 individuals and when infants/juveniles are targeted. However, of the seven remaining populations of L. catta with more than 100 individuals, only one is known to contain more than 500 animals, and we present evidence here that infants/juveniles are targeted. Moreover L. catta face significant other threats including habitat loss, bushmeat hunting, and climate change. Several actions could reduce the illegal capture and ownership of L. catta in Madagascar such as tourist behavior change initiatives, enforcement of laws, and alternative livelihoods for local people. These interventions are urgently needed and could be adapted to protect other exploited wildlife in the future. 
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