251 research outputs found

    Next-Generation Field Guides

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    To conserve species, we must first identify them. Field researchers, land managers, educators, and citizen scientists need up-to-date and accessible tools to identify organisms, organize data, and share observations. Emerging technologies complement traditional, book-form field guides by providing users with a wealth of multimedia data. We review technical innovations of next-generation field guides, including Web-based and stand-alone applications, interactive multiple-access keys, visual-recognition software adapted to identify organisms, species checklists that can be customized to particular sites, online communities in which people share species observations, and the use of crowdsourced data to refine machine-based identification algorithms. Next-generation field guides are user friendly; permit quality control and the revision of data; are scalable to accommodate burgeoning data; protect content and privacy while allowing broad public access; and are adaptable to ever-changing platforms and browsers. These tools have great potential to engage new audiences while fostering rigorous science and an appreciation for nature.Organismic and Evolutionary Biolog

    Prospective randomized comparison of a combined ultrasonic and pneumatic lithotrite with a standard ultrasonic lithotrite for percutaneous nephrolithotomy

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    PURPOSE: To compare the efficiency and cost effectiveness of a combined pneumatic and ultrasonic lithotrite (Lithoclast Ultra) and a standard ultrasonic lithotrite, (LUS-1) during percutaneous nephrolithotomy. MATERIALS AND METHODS: In a prospective randomized trial, 30 patients undergoing percutaneous nephrolithotomy (PCNL) were randomized to PCNL with either the combined pneumatic and ultrasonic lithotrite (PUL) or a standard ultrasonic lithotrite (SUL). Patient demographics, stone composition, location, pre- and post-operative stone burden, fragmentation rates, and device failures were compared. RESULTS: There were 13 patients in the PUL group and 17 patients in the SUL group. Stone burden and location were equal. Overall, 64% of the PUL group had hard stones (defined as stones that were either pure or a mixture of cystine [3], calcium oxalate monohydrate [CaOxMono; 2], and calcium phosphate [CaPO4; 2]), and four had soft stones (3 struvite and 1 uric acid [UA]). In the SUL group, there were eight hard stones (5 CaOxMono and 3 CaPO4), and six soft stones (4 calcium oxalate dihydrate [CaOxDi] and 2 UA) (P = 0.51). Stone composition data were unavailable for five patients. Fragmentation time for the PAL was 37 minutes versus 31.5 minutes for the SUL (P = 0.22). Stone retrieval and mean operative times were similar for both groups. There were a total of three (23.1%) device-related problems in the PUL group, and eight (47%) in the SUL group. There was one (7.7%) device malfunction in the PUL group due to probe fracture. There were two (11.7%) device failures in the SUL group; one failure required the device to be reset every 30 minutes, and the second was an electrical failure. Suction tubing obstruction occurred twice (15.3%) in the PUL group and 35.3% in the SU group (P = 0.35). The stone-free rates for the PUL and SUL were 46% and 66.7%, respectively (P = 0.26). CONCLUSION: Although the PUL was more costly, stone ablation and clearance rates were similar for both the combined pneumatic and ultrasonic device and the standard ultrasonic device. When stratified with respect to stone composition, the PUL was more efficient for harder stones, and the SUL was more efficient for softer stones

    Advances in aquatic insect systematics and biodiversity in the Neotropics: introduction

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    The Neotropical Region or Neotropics, contains vast expanses of rain forest and river systems representing some of the most biologically diverse ecosystems on Earth, but much of its resident biota remains undescribed and undocumented, and some of it is at risk of extirpation and extinction. Anthropogenic disturbances, especially deforestation, urbanization, and climate change, threaten the integrity of the Neotropics and its biodiversity. In the Neotropics, freshwater habitats are particularly susceptible to environmental stressors and freshwater species throughout the Neotropics have experienced marked declines greater than those of other groups when compared to marine and terrestrial systems. Advances in taxonomic descriptions, preparation of keys, and faunal assessments will aid future studies as well as conservation efforts

    The Kepler-10 planetary system revisited by HARPS-N: A hot rocky world and a solid Neptune-mass planet

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    Kepler-10b was the first rocky planet detected by the Kepler satellite and con- firmed with radial velocity follow-up observations from Keck-HIRES. The mass of the planet was measured with a precision of around 30%, which was insufficient to constrain models of its internal structure and composition in detail. In addition to Kepler-10b, a second planet transiting the same star with a period of 45 days was sta- tistically validated, but the radial velocities were only good enough to set an upper limit of 20 Mearth for the mass of Kepler-10c. To improve the precision on the mass for planet b, the HARPS-N Collaboration decided to observe Kepler-10 intensively with the HARPS-N spectrograph on the Telescopio Nazionale Galileo on La Palma. In to- tal, 148 high-quality radial-velocity measurements were obtained over two observing seasons. These new data allow us to improve the precision of the mass determina- tion for Kepler-10b to 15%. With a mass of 3.33 +/- 0.49 Mearth and an updated radius of 1.47 +0.03 -0.02 Rearth, Kepler-10b has a density of 5.8 +/- 0.8 g cm-3, very close to the value -0.02 predicted by models with the same internal structure and composition as the Earth. We were also able to determine a mass for the 45-day period planet Kepler-10c, with an even better precision of 11%. With a mass of 17.2 +/- 1.9 Mearth and radius of 2.35 +0.09 -0.04 Rearth, -0.04 Kepler-10c has a density of 7.1 +/- 1.0 g cm-3. Kepler-10c appears to be the first strong evidence of a class of more massive solid planets with longer orbital periods.Comment: 44 pages, 8 figures, accepted for publication in Ap

    COVID-19 is associated with early emergence of preeclampsia: results from a large regional collaborative

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    Objective: To examine the relationship between COVID-19 and preeclampsia (PreE) in a large, diverse population. Study Design: The COVID-19 in Pregnancy and The Newborn: State of Michigan Collaborative established a database of pregnant patients admitted to 14 institutions in Southern Michigan. Patients with COVID-19 (cases) were matched to 2 or 3 non-COVID patients (controls) on the same unit within 30 days of each case. Relative Risks (RR) were calculated using robust Poisson regression models with adjustment for covariates. Chi-squared test for trend was used to assess the increase in risk with the severity of disease. Results: 369 cases and 1,090 controls were delivered between March - October 2020. An increased risk of PreE (RR=1.8), driven almost entirely by an increase in preterm PreE (pretermPreE) (RR=2.85) was observed in COVID pregnancies (Table 1), with a dose-response relationship with symptomatology and severity (Table 2). The associations between COVID-19 disease and PreE or pretermPreE were independent of other risk factors, as demonstrated by the minimal changes in RR after adjustment for confounders (Table 1). However, African American (AA) COVID patients experienced pretermPreE 1.9 times more than COVID patients of other races (10.1 vs 5.3), an increase not observed in control patients. The strength of the association for COVID with PreE was comparable to the association of PreE with chronic hypertension and nulliparity (data not shown). Increasing symptoms and severity of COVID-19 were associated with an increased risk for PreE with placental lesions, even after adjustment for relevant covariates (Tables 1 & 2). Non-PreE COVID patients had an increased trend of placental lesions compared to non-COVID patients, reaching significance for intravillous thrombin. Conclusion: COVID-19 is significantly associated with early emergence of PreE, independent of known risk factors other than AA race. Our study shows that among patients predisposed to PreE, COVID-19 impacts PreE severity in that it leads to pretermPreE. Further studies on COVID-19 and PreE, with a focus on racial disparities, is warranted
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