457 research outputs found

    Development of Transgenic North American White Ash (Fraxinus americana) Expressing a Bacillus thuringiensis Protein for Management of the Emerald Ash Borer

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    White ash (WA), Fraxinus americana, is an integral part of the hardwood forest ecosystem. Economically, WA provides wood for important products such as baseball bats, tool handles, and hardwood flooring. Ecologically WA provides cover and mast to support wildlife. The emerald ash borer (EAB) is a significant threat to all ash species because of a lack of native resistance in North American ash trees, its rapid spread, and the ineffectiveness and expense of control measures. EAB is a non-native beetle that consumes tree vascular tissue while in the larval stage. The development of an Agrobacterium-mediated transformation protocol may impart systemic resistance to EAB via the Cry8Da toxic protein, which is lethal to EAB larvae and naturally found in Bacillus thuringiensis SDS-502. Development of a transformation system for WA will allow this gene or others imparting resistance to be successfully incorporated into the WA genome. Embryos were extracted, transformed, and cultured on a selection-regeneration medium, killing any non-transgenic tissues while allowing for transgenic shoot formation. Transformed hypocotyls will be further cultured on a selection-elongation medium to allow for shoot development, after which shoots will be rooted and acclimatized to greenhouse conditions. Additional confirmation of transgenic plants will be conducted through quantitative measurements of the FLAG protein, polymerase chain reaction, and finally a feeding assay performed with EAB larvae. WA hypocotyls regenerated shoots after transformation at a 27.8% efficiency rate. The transformed hypocotyls received 6 weeks of exposure to kanamycin in the selection medium, allowing for positive results within the scope of this project. This protocol can be used to further genetically modify F. americana, allowing for preservation of this ecologically and economically important species

    Electric-field driven insulating to conducting transition in a mesoscopic quantum dot lattice

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    We investigate electron transport through a finite two dimensional mesoscopic periodic potential, consisting of an array of lateral quantum dots with electron density controlled by a global top gate. We observe a transition from an insulating state at low bias voltages to a conducting state at high bias voltages. The insulating state shows simply activated temperature dependence, with strongly gate voltage dependent activation energy. At low temperatures the transition between the insulating and conducting states becomes very abrupt and shows strong hysteresis. The high-bias behavior suggests underdamped transport through a periodic washboard potential resulting from collective motion.Comment: 4 pages, 4 figure

    Consumers’ Preferences for Electronic Nicotine Delivery System Product Features: A Structured Content Analysis

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    To inform potential governmental regulations, we aimed to develop a list of electronic nicotine delivery system (ENDS) product features important to U.S. consumers by age and gender. We employed qualitative data methods. Participants were eligible if they had used an ENDS at least once. Groups were selected by age and gender (young adult group aged 18–25, n = 11; middle-age group aged 26–64, n = 9; and women’s group aged 26–64, n = 9). We conducted five individual older adult interviews (aged 68–80). Participants discussed important ENDS features. We conducted a structured content analysis of the group and interview responses. Of 34 participants, 68% were white and 56% were female. Participants mentioned 12 important ENDS features, including: (1) user experience; (2) social acceptability; (3) cost; (4) health risks/benefits; (5) ease of use; (6) flavors; (7) smoking cessation aid; (8) nicotine content; (9) modifiability; (10) ENDS regulation; (11) bridge between tobacco cigarettes; (12) collectability. The most frequently mentioned ENDS feature was modifiability for young adults, user experience for middle-age and older adults, and flavor for the women’s group. This study identified multiple features important to ENDS consumers. Groups differed in how they viewed various features by age and gender. These results can inform ongoing regulatory efforts

    Gas-permeable ethylene bags for the small scale cultivation of highly pathogenic avian influenza H5N1 and other viruses in embryonated chicken eggs

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    <p>Abstract</p> <p>Background</p> <p>Embryonated chicken eggs (ECE) are sometimes used for the primary isolation or passage of influenza viruses, other viruses, and certain bacteria. For small-scale experiments with pathogens that must be studied in biosafety level three (BSL3) facilities, inoculated ECE are sometimes manipulated and maintained in small egg incubators within a biosafety cabinet (BSC). To simplify the clean up and decontamination of an egg incubator in case of egg breakage, we explored whether ethylene breather bags could be used to encase ECE inoculated with pathogens. This concept was tested by determining embryo survival and examining virus yields in bagged ECE.</p> <p>Results</p> <p>Virus yields acceptable for many applications were attained when influenza-, alpha-, flavi-, canine distemper-, and mousepox viruses were propagated in ECE sealed within ethylene breather bags.</p> <p>Conclusions</p> <p>For many small-scale applications, ethylene breather bags can be used to encase ECE inoculated with various viruses.</p

    State-Level Policy Environments, Discrimination, and Victimization among Sexual and Gender Minority People

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    Legislation has been passed in some states to reduce discrimination and victimization toward sexual and gender minority people (SGM; people who are not solely heterosexual and/or whose gender identity is not equal to what is socially associated with sex assigned at birth). The purpose of these analyses is to test whether state-level policy environments are associated with past-year discrimination and victimization among SGM people. Cross-sectional data from The Population Research in Identity and Disparities for Equality (PRIDE) Study annual questionnaire (collected 2018–2019), a national study of the health of SGM adults in the USA, were used for these analyses. Measures included related to discrimination, victimization, and demographic characteristics. State-level policy environments were measured using data from the Movement Advancement Project. Logistic regression analyses evaluated state-level policy environment scores and past-year discrimination and victimization among gender identity categories. In this sample, 7044 people (gender minority n = 2530) were included. Cisgender sexual minority (odds ratio [OR] = 1.007, p = 0.041) and the gender expansive subgroup of gender minority people (OR = 1.010, p = 0.047) in states with more protective policy environments had greater odds of discrimination. The gender expansive subgroup was found to have greater odds of victimization in states with more protective policy environments (OR = 1.003, p \u3c 0.05). There was no relationship between state-level policy environments and victimization among any other study groups. SGM people may experience increased risk for discrimination and victimization despite legislative protections, posing continued risks for poor health outcomes and marginalization. Evaluation of factors (e.g., implementation strategies, systems of accountability) that influence the effectiveness of state-level polices on the reported experiences of discrimination and victimization among SGM people is needed

    Structure of the Polycomb Group Protein PCGF1 in Complex with BCOR Reveals Basis for Binding Selectivity of PCGF Homologs

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    SummaryPolycomb-group RING finger homologs (PCGF1, PCGF2, PCGF3, PCGF4, PCGF5, and PCGF6) are critical components in the assembly of distinct Polycomb repression complex 1 (PRC1)-related complexes. Here, we identify a protein interaction domain in BCL6 corepressor, BCOR, which binds the RING finger- and WD40-associated ubiquitin-like (RAWUL) domain of PCGF1 (NSPC1) and PCGF3 but not of PCGF2 (MEL18) or PCGF4 (BMI1). Because of the selective binding, we have named this domain PCGF Ub-like fold discriminator (PUFD). The structure of BCOR PUFD bound to PCGF1 reveals that (1) PUFD binds to the same surfaces as observed for a different Polycomb group RAWUL domain and (2) the ability of PUFD to discriminate among RAWULs stems from the identity of specific residues within these interaction surfaces. These data show the molecular basis for determining the binding preference for a PCGF homolog, which ultimately helps determine the identity of the larger PRC1-like assembly

    Abortion attempts without clinical supervision among transgender, nonbinary and gender-expansive people in the United States

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    Background Transgender, nonbinary and gender-expansive (TGE) people face barriers to abortion care and may consider abortion without clinical supervision. Methods In 2019, we recruited participants for an online survey about sexual and reproductive health. Eligible participants were TGE people assigned female or intersex at birth, 18 years and older, from across the United States, and recruited through The PRIDE Study or via online and in-person postings. Results Of 1694 TGE participants, 76 people (36% of those ever pregnant) reported considering trying to end a pregnancy on their own without clinical supervision, and a subset of these (n=40; 19% of those ever pregnant) reported attempting to do so. Methods fell into four broad categories: herbs (n=15, 38%), physical trauma (n=10, 25%), vitamin C (n=8, 20%) and substance use (n=7, 18%). Reasons given for abortion without clinical supervision ranged from perceived efficiency and desire for privacy, to structural issues including a lack of health insurance coverage, legal restrictions, denials of or mistreatment within clinical care, and cost. Conclusions These data highlight a high proportion of sampled TGE people who have attempted abortion without clinical supervision. This could reflect formidable barriers to facility-based abortion care as well as a strong desire for privacy and autonomy in the abortion process. Efforts are needed to connect TGE people with information on safe and effective methods of self-managed abortion and to dismantle barriers to clinical abortion care so that TGE people may freely choose a safe, effective abortion in either setting
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