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Effects of x-ray irradiation on fertilization and early development in quagga mussels (Dreissena bugensis)
No full textThe quagga mussel, Dreissena bugensis, is an invasive freshwater bivalve that causes significant economic and ecological damage. Numerous techniques are currently being investigated to help control their spread. X-ray irradiation has been used in different techniques to help control the spread of invasive species, either through decontamination or by the production of sterile male that reduce reproductive populations (Sterile Male Release Technique). Most studies have focused on terrestrial species, fewer looking at the effects of irradiation on aquatic species. This study was designed to evaluate the effects of x-ray irradiation on quagga mussels both in its effectiveness to kill mussels or to produce sterile males. Adult mussels were irradiated with a range of exposures from 0 (control), 6, 30, to 50 Gy to determine the effect on quagga mussel survival and impact on reproduction. The results demonstrated that x-ray treated quagga mussels had lower developmental success than the control. Adult quagga mussels were highly tolerant of x-ray irradiation with high survival rates (> 95%) after treatment. Mussels from all treatments produced motile sperm and these sperm were able to bind and fuse with eggs. There was a decrease in sperm binding between treatments, but fertilization still occurred. Fertilized eggs in all treatments were able to divide and produce swimming trochophores, but irradiation appears to decrease development between zygote and trochophore stage. The current experiment was not able to produce completely sterile males, even at the highest irradiation of 50 Gy in a single 8-minute session. The current experiment did not find an x-ray dose leading to the generation of 100% sterile males. Even at higher doses, x-ray irradiation may not be realistic for implementation
Harmonizing Stellar Histories: Using Spectroscopy of Open Clusters to Calibrate Asteroseismic Ages
No full textPrecise stellar ages for field stars are still elusive today for several reasons. For example, there are many different methods to determine the ages of stars, and it is difficult to trace the formation history of field stars. Open clusters allow for some reduction of age errors since they are environments with different types of stars to study that formed at the same time from the same material. Current methods to determine age estimates of stars, such as spectroscopy and asteroseismology, individually have very large uncertainties. Combining these two age estimation methods would significantly reduce this uncertainty even further. For this study, metallicities and asteroseismology data for a set of open clusters are combined to produce a new asteroseismic age-metallicity-mass relation to reduce the uncertainty in age estimates of stars. While open clusters are ideal age calibrators, few have good asteroseismic data. To date, there have been no larger-scale surveys of open clusters that compare asteroseismology and spectroscopy estimates of stellar ages, due to the limits of area coverage from the Kepler mission. The approach of this study is to more than double the number of clusters with high-quality asteroseismology and high-resolution abundance determinations by observing a sample of 10 open clusters. These clusters were chosen because they overlapped with Kepler 2 (K2) campaign fields to utilize the asteroseismology observations of giant stars in the K2 fields. We analyze the clusters and use The Cannon to measure abundances of [Fe/H], [Mg/Fe], [Si/Fe], [Ni/Fe], [Ca/Fe], [Na/Fe], and [V/Fe] and determine cluster membership. Using this sample, we present a new asteroseismic age-metallicity-mass relation that improves the age precision for Milky Way disk field stars using asteroseismology
How does surface area availability affect water resource use by bats?
No full textUrban biodiversity provides essential ecosystem services, but urban areas often lack the resources necessary for wildlife. Water represents an essential resource, but availability and accessibility of water sources vary, particularly between taxa. Bats, for example, swoop down to the water’s surface to drink on the wing and their ability to do this is influenced by the size and shape of the water source. We explored this drinking ability further at six ponds in Fort Worth, Texas using drones to record fundamental and realized surface area, maximum patch size, and longest continuous stretch. We compared these metrics with bat activity recorded in behavioral and acoustic surveys, and found that the latter showed the strongest relationship with drinking activity. On further investigation, we determined that this correlation was driven by clutter on the surface of the water. Our study highlighted that water sources need uninterrupted stretches to represent an accessible water resource
Case of the Mondays: Examining Media Coverage of Oral Arguments Based on Weekday Selection
No full textThe US Supreme Court follows a fixed weekly schedule, with specific days assigned for tasks. Oral arguments – held on select Mondays, Tuesdays, and Wednesdays – are the only public part of the Court’s decision-making process. We argue that news outlets consider the Court’s schedule when deciding which arguments to cover. To test this, we analyze media coverage of oral arguments from the 2019, 2020, and 2021 terms. Our findings reveal a notable disparity, with Monday arguments receiving the most coverage. This highlights the influence of the Court’s schedule on media attention, shaping public awareness, and the perceived importance of cases
Exploring the AI Adoption Challenges in Small Enterprises in Non-Technology Industries
No full textThis study examines the challenges and strategies associated with adopting artificial intelligence (AI) in small enterprises within non-technology industries. Utilizing a mixed-methods approach, the research integrates quantitative analysis of datasets, including AI risk repositories and tools, with qualitative insights from case studies of GetTransfer, FC Beauty, and PhoenixFire. The findings reveal that while AI tools like productivity and chat applications dominate due to their accessibility and utility, small businesses face significant hurdles, including resource constraints, technical expertise deficits, and vague ethical standards. Case studies highlight contrasting approaches: internal AI development versus strategic partnerships with external experts. This study underscores the importance of resource allocation, leadership, and ethical frameworks in mitigating AI adoption barriers. The implications extend to providing actionable recommendations for small enterprises, while the study acknowledges limitations such as the narrow case study scope and reliance on secondary data. Future research opportunities include broader longitudinal studies and exploration of advanced AI applications across diverse non-technology sectors
Testing an HPV Vaccine Decision Aid for 27- to 45-Year-Old Adults in the United States: A Randomized Trial
No full textBackground In the United States, human papillomavirus (HPV) vaccination among 27- to 45-y-olds (mid-adults) is recommended based on shared clinical decision making with a health care provider. We developed a patient decision aid tool to support the implementation of this mid-adult HPV vaccination guideline. The purpose of this study was to evaluate the effect of a patient decision aid tool for HPV vaccination, HPV DECIDE, compared with an information fact sheet among mid-adults who have not received the HPV vaccine. Method Participants were recruited between December 2023 and January 2024. We used a randomized Solomon, 4-group, pretest/posttest design with mid-adults aged 27 to 45 y who were unvaccinated for HPV and balanced based on sex (n = 612). The primary outcome was decisional conflict. Intermediate outcomes included knowledge, behavioral expectancies, self-efficacy, and perceived risk. Variables were measured using validated scales. Pretest sensitization was not present; intervention and control groups were compared. Fixed-effects inverse-variance weighting was used to pool effect estimates and determine meta-analytic statistical significance across tests with and without pretest controls. Results Participants in the intervention group had significantly lower total decisional conflict scores (B = −3.58, P = 0.007) compared with the control group. Compared with the control group, participants in the intervention group showed higher knowledge (B = 0.48, P = 0.020), greater intention to receive (B = 0.196, P = 0.049) and discuss the HPV vaccine (B = 0.324, P ≤ 0.001), and greater self-efficacy about HPV vaccine decision making (B = 3.28, P = 0.043). There were no statistically significant results for perceived risks of HPV infection. Conclusions The HPV DECIDE tool for mid-adult HPV vaccination shows promise for immediate reductions in decisional conflict and improvement in knowledge, intentions, and self-efficacy about the HPV vaccine. Future studies are warranted to evaluate the effectiveness of this patient decision aid tool in real-world settings. Highlights Shared clinical decision making is recommended for HPV vaccination with mid-adults. A patient decision aid for HPV vaccination reduced decisional conflict for mid-adults. The HPV vaccine patient decision aid was acceptable to mid-adults
Efficacy of the Flo App in Improving Health Literacy, Menstrual and General Health, and Well-Being in Women: Pilot Randomized Controlled Trial
No full textBackground Reproductive health literacy and menstrual health awareness play a crucial role in ensuring the health and well-being of women and people who menstruate. Further, awareness of one’s own menstrual cycle patterns and associated symptoms can help individuals identify and manage conditions of the menstrual cycle such as premenstrual syndrome (PMS) and premenstrual dysphoric disorder (PMDD). Digital health products, and specifically menstrual health apps, have the potential to effect positive change due to their scalability and ease of access. Objective The primary aim of this study was to measure the efficacy of a menstrual and reproductive health app, Flo, in improving health literacy and health and well-being outcomes in menstruating individuals with and without PMS and PMDD. Further, we explored the possibility that the use of the Flo app could positively influence feelings around reproductive health management and communication about health, menstrual cycle stigma, unplanned pregnancies, quality of life, work productivity, absenteeism, and body image. Methods We conducted 2 pilot, 3-month, unblinded, 2-armed, remote randomized controlled trials on the effects of using the Flo app in a sample of US-based (1) individuals who track their cycles (n=321) or (2) individuals who track their cycles and are affected by PMS or PMDD (n=117). Results The findings revealed significant improvements at the end of the study period compared to baseline for our primary outcomes of health literacy (cycle tracking: D̄=1.11; t311=5.73, P<.001; PMS or PMDD: D̄=1.20; t115=3.76, P<.001) and menstrual health awareness (D̄=3.97; t311=7.71, P<.001), health and well-being (D̄=3.44; t311=5.94, P<.001), and PMS or PMDD symptoms burden (D̄=–7.08; t115=–5.44, P<.001). Improvements were also observed for our secondary outcomes of feelings of control and management over health (D̄=1.01; t311=5.08, P<.001), communication about health (D̄=0.93; t311=2.41, P=.002), menstrual cycle stigma (D̄=–0.61; t311=–2.73, P=.007), and fear of unplanned pregnancies (D̄=–0.22; t311=–2.11, P=.04) for those who track their cycles, as well as absenteeism from work and education due to PMS or PMDD (D̄=–1.67; t144=–2.49, P=.01). Conclusions These pilot randomized controlled trials demonstrate that the use of the Flo app improves menstrual health literacy and awareness, general health and well-being, and PMS or PMDD symptom burden. Considering the widespread use and affordability of the Flo app, these findings show promise for filling important gaps in current health care provisioning such as improving menstrual knowledge and health. Trial Registration OSF Registries osf.io/pcgw7; https://osf.io/pcgw7 ; OSF Registries osf.io/ry8vq; https://osf.io/ry8v
The Smith Cloud: A Dust Bowl Barrelling through Our Galactic Halo
No full textAround our Milky Way, there is no shortage of gas being ejected and accreted into our Galaxy. Among these high-velocity clouds (HVCs) is the Smith Cloud: a particular HVC that has been studied in-depth for over 60 years. Recent studies have explored the chemistry of the Smith Cloud, finding elemental abundances of [[N II]/Hα] = -0.49 ± 0.07 in the main body and an average UV-based sulfur abundance of [S/H] = -0.28 ± 0.14 in the tail. With the discrepancy in chemical abundances as well as a potential gradient of metallicity and trajectory of the Smith Cloud, there have been countless questions as to its origin. To probe the question of origin, we explored further aspects of the chemistry of the Smith Cloud using HI-21cm emission-line spectra from the Green Bank Telescope and UV absorption-line spectra from the Cosmic Origins Spectrograph on the Hubble Space Telescope. We utilized these observations to provide the first detection of dust within the Smith Cloud ([Si/S] = -1.04 ± 0.10 ± 0.07) and two new metallicity measurements of ([S/H] = -0.09 ± 0.18; [N/H] = -1.06 ± 0.18). We also provide the first detection of a UV nitrogen abundance. This could mean that nitrogen is under-abundant in the Smith Cloud. These results could indicate an even higher metallicity in the main body of the Smith Cloud. Our first measurement of the dust content of the Smith Cloud shows that the Smith Cloud very likely came from our Milky Way galaxy
Thriving during the transition to fostering and adoptive parenthood: A test of the extended theoretical model of communal coping
No full textThis study tested the extended TMCC in the context of foster and adoptive parents,
providing insight into how they engage in coping during their transition to parenthood. Participants (n = 203) completed an online survey that assessed their communication and relational quality, communal coping, perceived stigma, chronicity, control, and parental adjustment during their transition to adoptive or foster parenthood. Data was analyzed using correlations and Hayes’ PROCESS for SPSS. Results indicated that communal coping mediates the relationship between communication openness, communication efficacy, relational trust, relational commitment, and relational closeness and parental adjustment. Additionally, it confirmed control as impactful in the process of communal coping. Practically, this study demonstrates how communal coping is a powerful strategy for foster and adoptive parents adjusting to parenthood and it extends the TMCC to understand the experiences of foster and adoptive parents
Explosive galactic weather: Winds from the largest cloud in the local group
No full textThe Large Magellanic Cloud (LMC), a companion to our galaxy that lies only one Milky Way diameter away, provides us with a unique opportunity to study galactic winds in great detail. When massive stars die, they explode through powerful supernovae explosions which release an enormous amount of energy which can drive galactic winds. We are using archival HI 21-cm emission line observation data from the GASS and GASKAP surveys as part of “The LMC’s Galactic Wind through the Eyes of ULYSSES” Hubble Legacy Archive program to understand the kinematic properties of this wind. With multiple gas clouds in every direction, we often detect complex structures that we are modeling using Specutils, a Python library for Gaussian fitting. This detailed analysis of a resolved galactic wind will ultimately aid in our knowledge by characterizing the kinematic boundary of the LMC’s winds from its disk