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BACKGROUND: Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections continue to increase in the United States. Advancement in technology with point-of-care (POC) testing can improve the overall treatment of sexually transmitted infections (STI) in the emergency department (ED) by shortening the time to test result and administration of accurate treatment. The purpose of this study was to assess if the POC test reduced the rate of overtreatment for CT and/or NG compared to the standard-of-care (SOC) test. METHODS: This retrospective cohort study included adult patients tested for CT and NG at two urban EDs between August 2020 and October 2022. This cohort excluded hospital admissions, elopement, pregnancy, rectal and oral samples, victims of sexual assault, and diagnoses for which antimicrobial treatment overlapped that of CT/NG. The primary outcome assessed overtreatment, defined as receiving treatment in the ED or a prescription prior to discharge for patients who tested negative for CT and/or NG. Secondary outcomes included undertreatment rates, overtreatment rates in select populations, test turnaround time, and ED length of stay (LOS). RESULTS: Of 327 patients screened, 97 patients were included in the SOC group and 100 in POC. Overtreatment for CT was provided in zero POC patients and 29 (29.9%) SOC patients (p < 0.001). NG was overtreated in 1 (1%) POC and 23 (23.7%) SOC (p < 0.001). POC was associated with undertreatment of CT and/or NG in two patients, compared to four patients tested with SOC. Overall, treatment was deemed inappropriate for 5 (5%) of those tested with POC, compared to 35 (36%) tested with SOC (p < 0.001). There was no difference in ED LOS (2.7 vs 3.01 h, p = 0.41). CONCLUSIONS: POC testing facilitated the return of results prior to patients being discharged from the ED. Compared to standard testing, POC improved appropriateness of CT and NG treatment by reducing the rates of overtreatment.

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Jiuzhaigou National Park (JNP) is a site of global conservation significance. Conservation policies in JNP include the implementation of two national reforestation programs to increase forest cover and the exclusion of local land-use. We use archaeological excavation, ethnographic interviews, remote sensing and vegetation surveys to examine the implications of these policies for non-forest, montane meadows. We find that Amdo Tibetan people cultivated the valley for >2,000 years, creating and maintaining meadows through land clearing, burning and grazing. Meadows served as sites for gathering plants and mushrooms and over 40 % of contemporary species are ethnobotanically useful. Remote sensing analyses indicate a substantial (69.6 %) decline in meadow area between 1974 and 2004. Respondents report a loss of their "true history" and connections to the past associated with loss of meadows. Conservation policies intended to preserve biodiversity are unintentionally contributing to the loss of these ecologically and culturally significant meadow habitats.

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PREMISE OF THE STUDY: Rare plants may be rare, in part, because they are more susceptible to damage by predispersal insect seed predators than widespread congeneric species; thus, seed predation may be an important determinant of plant rarity. Scant evidence exists to either support or reject this hypothesis, limiting our ability to predict herbivore effects on plant rarity. We used a comparative framework to test this hypothesis in rare-common, sympatric congeners. METHODS: We compared seed consumption by insect type and seed production among a rare Astragalus (Fabaceae) species and two sympatric, widespread congeners. We measured plant traits and tested whether traits were correlated with seed damage within and among rare-common species. KEY RESULTS: Seed predation was significantly higher in a rare species than in common congeners over 2 yr. Seed production per pod was significantly lower in the rare species. Seed weevils exclusively consumed seeds of the rare species. Higher seed predation in the rare species is related to a combination of factors: plant phenology, dispersal ability, and vigor; seed predator identity; and insect phenology. CONCLUSIONS: Our results support the hypothesis that a rare plant is more susceptible to seed predators than two common, sympatric congeners. Seed predator reduction is a promising management tool to increase seed-set, recruitment, and survival of the rare species. Further studies that compare rare-common, sympatric congeners are greatly needed to broadly evaluate the hypothesis concerning rarity and susceptibility to seed predators and to inform conservation plans for rare species.

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The conservation of rare plant species hinges on our ability to identify the underlying mechanisms that limit rare plant populations. Theory on rarity suggests that both predispersal seed predation and competition can be important mechanisms influencing abundance and/or distribution of rare plant populations. Yet few studies have tested these interactions, and those that have evaluated each mechanism independently. Astragalus sinuatus Piper (Whited's milkvetch) is a narrow endemic plant species restricted to eight populations within a 10-km2 area in eastern Washington. We used experimental and observational methods to test the effects of native insect predispersal seed predators and an invasive grass (Bromus tectorum L. [cheatgrass]) on seed set and population density of A. sinuatus. We quantified per capita seed production and pod predation rates across four sites and among four years. Seed predation rates were high across four sites (66-82%) and all years (65-82%). Experimental reduction of predispersal seed predators significantly increased per capita seed set of A. sinuatus (164-345%) at two experimental sites. Concurrently, two seed addition experiments demonstrated the effect of seed loss and presence of B. tectorum on seedling recruitment and establishment of A. sinuatus over four growing seasons. In the first seed addition experiment, we found no difference in recruitment and establishment between low (40) and high (120) seed addition levels. In the second addition experiment (one level of addition; 40 seeds), we found that recruitment and survivorship increased 200% in plots where B. tectorum was removed compared to plots where B. tectorum was present. Thus, seed addition had no impact in the presence of B. tectorum; conversely, in the absence of B. tectorum, seed addition was highly effective at increasing population numbers. Results suggest that, in areas where B. tectorum is present, recruitment is site limited, and it is seed limited when B. tectorum is absent. We recommend that managers reduce B. tectorum in an effort to increase population growth of A. sinuatus; in areas where B. tectorum is absent, short-term reduction of insect predators should be considered as a strategy to increase population growth of this rare species.

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Both pollination by animals and mycorrhizal symbioses with fungi are believed to have been important for the diversification of flowering plants. However, the mechanisms by which these above- and belowground mutualisms affect plant speciation and coexistence remain obscure. We provide evidence that shifts in pollination traits are important for both speciation and coexistence in a diverse group of orchids, whereas shifts in fungal partner are important for coexistence but not for speciation. Phylogenetic analyses show that recently diverged orchid species tend either to use different pollinator species or to place pollen on different body parts of the same species, consistent with the role of pollination-mode shifts in speciation. Field experiments provide support for the hypothesis that colonization of new geographical areas requires adaptation to new pollinator species, whereas co-occurring orchid species share pollinator species by placing pollen on different body parts. In contrast to pollinators, fungal partners are conserved between closely related orchid species, and orchids recruit the same fungal species even when transplanted to different areas. However, co-occurring orchid species tend to use different fungal partners, consistent with their expected role in reducing competition for nutrients. Our results demonstrate that the two dominant mutualisms in terrestrial ecosystems can play major but contrasting roles in plant community assembly and speciation.

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