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Vibrio parahaemolyticus(VP) is a bacterial pathogen found in brackish and marine water that infects many marine organisms, such as oysters and shrimp. Consumption of raw or undercooked seafood contaminated withV. parahaemolyticusis a primary cause of seafood-borne gastroenteritis in humans. Due to increasing ocean temperatures,V. parahaemolyticuscontamination of oyster beds in the United States has spread up the east and west coasts to the northern-most states. Promising new research is exploring the isolation of bacteriophages againstV. parahaemolyticuswith a long-term goal to possibly decontaminate oyster beds, thereby expanding the harvest season and allowing for safer consumption of seafood. In this study, store-bought oysters harvested from the Chesapeake Bay in Virginia were used to isolate four bacteriophages with activity against a specificV. parahaemolyticusstrain. A standard double agar overlay plaque assay was used to identify phage activity. After phage isolation, the genomes were sequenced, and transmission electron microscopy (TEM) was performed to visualize the virions. The genomes and TEM images revealed four distinct phages. Three of the phages are distinct isolates that exhibit podovirus-like morphology with short tails and genome sizes of approximately 43 kbp. One phage has siphovirus-like morphology and is a mid-sized tailed phage with a genome size of 80 kbp. Although spot tests performed with the oyster homogenates on up to 10 differentV. parahaemolyticusstrains recovered activity across a wide range of hosts, plaque assays with the isolated phages showed limited host range. Future work will be necessary to determine the viability of using the bacteriophages for elimination ofV. parahaemolyticusin harvested oysters, treatment of aquaculture seed and spat, and/or the environment. 

ABSTRACT Venturia canescensis a parasitoid wasp that harbors a domesticated endogenous virus (DEV) and parasitizes host insects likeEphestia kuehniella. TheV. canescensDEV evolved from an alphanudivirus and produces virus-like particles (VLPs) in females that protect wasp eggs from a host immune defense called encapsulation. In contrast, very few DEV genes required for VLP formation and function have been identified. In this study, we characterized fiveV. canescensDEV genes of unknown function that all nudiviruses encode. Three of these genes are single copy (OrNVorf18-like,OrNVorf61-like, andOrNVorf76-like), whileOrNVorf41-likehas expanded into a six-member family andOrNVorf47-likehas expanded into a three-member family. Sequence analysis indicated all of these genes retain essential motifs present in nudivirus homologs, while transmission electron microscopy (TEM) studies characterized the timing of VLP formation during the wasp pupal stage. RNA interference (RNAi) assays identifiedOrNVorf18-like,OrNVorf61-like,OrNVorf41-like-1,andOrNVorf41-like-2as genes that are required for normal VLP formation. Knockdown ofOrNVorf47-likefamily members did not affect VLP formation but did disable binding of VLPs toV. canescenseggs and protection against encapsulation. Disabled formation of VLPs in response to RNAi knockdown ofOrNVorf18-like,OrNVorf61-like,OrNVorf41-like-1,andOrNVorf41-like-2also resulted in wasp eggs being encapsulated. In contrast, knockdown ofOrNVorf76-likehad no effect on VLP assembly, egg binding, or encapsulation. Altogether, reported results significantly advance our understanding ofV. canescensVLP (VcVLP) formation and function. IMPORTANCEUnderstanding howV. canescenscoopted an alphanudivirus to produce VcVLPs is of interest to the study of virus evolution. Our results show that three nudivirus core genes have essential functions in VcVLP formation, while one is essential for the novel function of binding to wasp eggs and protection from encapsulation, which is the most important immune defense of insects against parasitoids. 

Abstract We study the black hole mass–host galaxy stellar mass relation,M_BH–M_*, for a sample of 706z ≲ 1.5 andi ≲ 24 optically variable active galactic nuclei (AGNs) in three Dark Energy Survey (DES) Deep Fields: C3, X3, E2, which partially cover Chandra Deep Field-South, XMM Large Scale Structure survey, and European Large Area ISO Survey, respectively. The parent sample was identified by optical variability from the DES supernova survey program imaging. Using publicly available spectra and photometric catalogs, we consolidate their spectroscopic redshifts, estimate their black hole masses using broad line widths and luminosities, and obtain improved stellar masses using spectral energy distribution fitting from X-ray to mid-infrared wavelengths. Our results confirm previous work from Hyper-Suprime Camera imaging that variability searches with deep, high-precision photometry can reliably identify AGNs in low-mass galaxies up toz ∼ 1. However, we find that the hosted black holes are more massive than predicted by the local AGN relation, fixing host galaxy stellar mass. Instead,z ∼ 0.1–1.5 variability-selected AGNs lie in between theM_BH–M_*relation for local inactive early-type galaxies and local active galaxies. This result agrees with most previous studies of theM_BH–M_*relation for AGNs at similar redshifts, regardless of the selection technique. We demonstrate that studies of variability-selected AGN provide critical insights into the low-mass end of theM_BH–M_*relation, shedding light on the occupation fraction of that provides constraints on early black hole seeding mechanisms and self-regulated feedback processes during their growth and coevolution with their hosts. 

Abstract How do witnesses make identification decisions when viewing a lineup?Understanding the witness decision-making process is essential for researchers to develop methods that can reduce mistaken identifications and improve lineup practices. Yet, the inclusion of fillers has posed a pivotal challenge to this task because the traditional signal detection theory is only applicable to binary decisions and cannot easily incorporate lineup fillers. This paper proposes a multi-item signal detection theory (mSDT) model to help understand the witness decision-making process. The mSDT model clarifies the importance of considering the joint distributions of suspect and filler signals. The model also visualizes the joint distributions in a multivariate decision space, which allows for the incorporation of all eyewitness responses, including suspect identifications, filler identifications, and rejections. The paper begins with a set of simple assumptions to develop the mSDT model and then explores alternative assumptions that can potentially accommodate more sophisticated considerations. The paper further discusses the implications of the mSDT model. With a mathematical modeling and visualization approach, the mSDT model provides a novel theoretical framework for understanding eyewitness identification decisions and addressing debates around eyewitness SDT and ROC applications. 

Abstract Background and aimsPlant interactions with soil microbial communities are critical for understanding plant health, improving horticultural and agricultural outcomes, and maintaining diverse natural communities. In some cases, disease suppressive soils enhance plant survival in the presence of pathogens. However, species-specific differences and seasonal variation complicate our understanding of the drivers of soil fungal communities and their consequences for plants. Here, we aim to describe soil fungal communities acrossRhododendronspecies and seasons as well as the test for fungal indicators ofRhododendronspecies in the soil. Further, we test possible mechanisms governing disease suppressive soils to the oomycete pathogenPhytophthora cinnamomi. Variation in disease susceptibility to this pathogen across species and clades allows us to test for possible fungal drivers of disease suppressive soils. MethodsWe conducted high throughput sequencing of the fungal communities found in soil collected under 14Rhododendronspecies and across 2 seasons (April, October) at two sites in Ohio, USA. Phylogenetic analyses were used to ask whether fungal community composition correlated with increased plant survival with the addition of whole soil communities from a prior greenhouse experiment. ResultsEffects ofRhododendronspecies (R² = 0.13), season (R² = 0.01) and their interaction on fungal communities (R² = 0.11) were statistically significant. Fungal community composition negatively correlated with survival following exposure to whole soil microbial communities, though this result depended on the presence ofR. minus. Forty-fiveTrichodermataxa were identified across our soil samples, and someTrichodermawere significantly associated with particularRhododendronspecies (e.g.Trichoderma atroviridewas associated withR. molle) in indicator species analyses. ConclusionThe correlation between plant responses to soil biotic communities and fungal community composition, as well as the presence of potential beneficial taxa such asTrichodermaand mycorrhizal fungi, are consistent with fungal-mediated survival benefits from the pathogenPhytophthora cinnamomi. 

Recommender systems are usually designed by engineers, researchers, designers, and other members of development teams. These systems are then evaluated based on goals set by the aforementioned teams and other business units of the platforms operating the recommender systems. This design approach emphasizes the designers’ vision for how the system can best serve the interests of users, providers, businesses, and other stakeholders. Although designers may be well-informed about user needs through user experience and market research, they are still the arbiters of the system’s design and evaluation, with other stakeholders’ interests less emphasized in user-centered design and evaluation. When extended to recommender systems for social good, this approach results in systems that reflect the social objectives as envisioned by the designers and evaluated as the designers understand them. Instead, social goals and operationalizations should be developed through participatory and democratic processes that are accountable to their stakeholders. We argue that recommender systems aimed at improving social good should be designedbyandwith, not justfor, the people who will experience their benefits and harms. That is, they should be designed in collaboration with their users, creators, and other stakeholders as full co-designers, not only as user study participants. 

Multistakeholder recommender systems are those that account for the impacts and preferences of multiple groups of individuals, not just the end users receiving recommendations. Due to their complexity, these systems cannot be evaluated strictly by the overall utility of a single stakeholder, as is often the case of more mainstream recommender system applications. In this article, we focus our discussion on the challenges of multistakeholder evaluation of recommender systems. We bring attention to the different aspects involved—from the range of stakeholders involved (including but not limited to providers and consumers) to the values and specific goals of each relevant stakeholder. We discuss how to move from theoretical principles to practical implementation, providing specific use case examples. Finally, we outline open research directions for the RecSys community to explore. We aim to provide guidance to researchers and practitioners about incorporating these complex and domain-dependent issues of evaluation in the course of designing, developing, and researching applications with multistakeholder aspects. 

This full paper introduces a larger project exploring how the development of time management and metacognition skills may positively impact the agency of first-year engineering students and their success, which we acknowledge can be measure in traditional ways (e.g. persistence, achievement) and non-traditional ways (e.g. well-being). The ever-evolving characteristics of college students demand continuous actualization of educational strategies. It is known that most college students nowadays belong to Generation Z, who are technology-natives, ethnically diverse and are on track to become the most educated generation. However, they also struggle the most with their mental health, which is influenced by contemporary challenges such as mass shootings, money and work stressors, the political climate, and stresses and losses derived from learning within a pandemic. If we honor our commitment to support their success, we need to consider these strengths and weaknesses. As well as considering the critical role of well-being in their success. As part of the project, we collected baseline measures of the constructs of interest in a first-year engineering course at a University in the U.S. East, using established and validated instruments. The measures took place before and after students were provided with formal content about metacognition and time management within the Fall 2024 semester. Paired t-tests comparisons were conducted to evaluate gains in metacognitive and time management skills as well as to explore changes in well-being. Interpretations and implications of our results in the first-year engineering experience are offered.