2,769 research outputs found
COVID-19 social distancing measures and economic growth: Distinguishing short- and long-term effects
Social distancing policies have been criticized for their adverse effect on economies. However, we evidence that while they have a short-run adverse effect, they also have a long-run recovery effect on economic growth. Utilizing quarterly gross domestic product (GDP) growth rate data from OECD member states, we find that the medium-term recovery effect of stringent social distancing policies on economic growth is three times higher the short-term adverse effect. We additionally investigate social distancing measures with sub-components of GDP, as well as the conditioning roles of institutional factors
Where teachers are few: documenting available faculty in five Tanzanian medical schools.
BACKGROUND:Faced with one of the lowest physician-to-population ratios in the world, the Government of Tanzania is urging its medical schools to train more physicians. The annual number of medical students admitted across the country rose from 55 in the 1990s to 1,680 approved places for the 2015/16 academic year. These escalating numbers strain existing faculty. OBJECTIVE:To describe the availability of faculty in medical schools in Tanzania. DESIGN:We identified faculty lists published on the Internet by five Tanzanian medical schools for the 2011/12 academic year and analyzed the appointment status, rank, discipline, and qualifications of faculty members. RESULTS:The five schools reported 366 appointed faculty members (excluding visiting, part-time, or honorary appointments) for an estimated total enrolled student capacity of 3,275. Thirty-eight percent of these faculty were senior lecturers or higher. Twenty-seven percent of the appointments were in basic science, 51% in clinical science, and 21% in public health departments. The most populated disciplines (more than 20 faculty members across the five institutions) were biochemistry and molecular biology, medicine, obstetrics and gynecology, pediatrics, and surgery; the least populated disciplines (less than 10 faculty members) were anesthesiology, behavioral sciences, dermatology, dental surgery, emergency medicine, hematology, ophthalmology, orthopedics, otorhinolaryngology, oncology and radiology, psychiatry. These figures are only indicative of faculty numbers because of differences in the way the schools published their faculty lists. CONCLUSIONS:Universities are not recruiting faculty at the same rate that they are admitting students, and there is an imbalance in the distribution of faculty across disciplines. Although there are differences among the universities, all are struggling to recruit and retain staff. If Tanzanian universities, the government, donors, and international partners commit resources to develop, recruit, and retain new faculty, Tanzania could build faculty numbers to permit a quality educational experience for its doctors of tomorrow
Second International Lygus Symposium: Asilomar Conference Grounds, Pacific Grove, California, April 15-19 2007
The Second International Lygus Symposium brought together 52 entomologists from six nations and 11 states representing universities, public agencies, and private entities to discuss the latest research on Lygus species and their relatives. Symposium topics included Lygus biology, behavior and ecology, IPM, insecticides and resistance, and biological control. Papers and posters dealt with Lygus as a pest of several crops, including cotton, strawberries, seed alfalfa, canola, dry beans, cucumbers, cereals, peaches, and new crops guayule and lesquerella. Intercrop movement of Lygus2008200820082008 species was another important topic of many presentations. In the capstone session, participants identified needs and priorities for ongoing Lygus research and education (available at http://ag.arizona.edu/apmc/Arid_SWPMC_RAMP.html). The conference was sponsored in part by FMC Corporation, the University of Arizona Arizona Pest Management Center, the University of California Statewide IPM Program, and a grant to Ellsworth et al. (CRIS# 0207436) from the USDA-CSREES, Risk Avoidance and Mitigation Program (RAMP)
Whole Systems Inquiry: Designing Large Educational Events
Whole systems inquiry (WSI) helps people see complex topics as functional activities with inputs, outputs, interactions, and performance of the system over time. The authors used WSI to design a national symposium with 800 attendees who responded to two questions at the end of 70 topical sessions. Responses were aggregated onto a mega-map, synthesized into themes, and drawn as an emerging system. Work groups compared emerging themes with national priorities while individual participants evaluated utility in their disciplinary programs. We conclude that large meetings can be designed as functional systems with participation, synthesis, and evaluation of intentional learning
Outlook for tuberculosis elimination in California: An individual-based stochastic model.
RationaleAs part of the End TB Strategy, the World Health Organization calls for low-tuberculosis (TB) incidence settings to achieve pre-elimination (<10 cases per million) and elimination (<1 case per million) by 2035 and 2050, respectively. These targets require testing and treatment for latent tuberculosis infection (LTBI).ObjectivesTo estimate the ability and costs of testing and treatment for LTBI to reach pre-elimination and elimination targets in California.MethodsWe created an individual-based epidemic model of TB, calibrated to historical cases. We evaluated the effects of increased testing (QuantiFERON-TB Gold) and treatment (three months of isoniazid and rifapentine). We analyzed four test and treat targeting strategies: (1) individuals with medical risk factors (MRF), (2) non-USB, (3) both non-USB and MRF, and (4) all Californians. For each strategy, we estimated the effects of increasing test and treat by a factor of 2, 4, or 10 from the base case. We estimated the number of TB cases occurring and prevented, and net and incremental costs from 2017 to 2065 in 2015 U.S. dollars. Efficacy, costs, adverse events, and treatment dropout were estimated from published data. We estimated the cost per case averted and per quality-adjusted life year (QALY) gained.Measurements and main resultsIn the base case, 106,000 TB cases are predicted to 2065. Pre-elimination was achieved by 2065 in three scenarios: a 10-fold increase in the non-USB and persons with MRF (by 2052), and 4- or 10-fold increase in all Californians (by 2058 and 2035, respectively). TB elimination was not achieved by any intervention scenario. The most aggressive strategy, 10-fold in all Californians, achieved a case rate of 8 (95% UI 4-16) per million by 2050. Of scenarios that reached pre-elimination, the incremental net cost was 48 billion. These had an incremental cost per QALY of 3.1 million. A more efficient but somewhat less effective single-lifetime test strategy reached as low as $80,000 per QALY.ConclusionsSubstantial gains can be made in TB control in coming years by scaling-up current testing and treatment in non-USB and those with medical risks
Macroalgal meadow habitats support fish and fisheries in diverse tropical seascapes
Ecosystems are linked by the movement of organisms across habitat boundaries and the arrangement of habitat patches can affect species abundance and composition. In tropical seascapes many coral reef fishes settle in adjacent habitats and undergo onto-genetic habitat shifts to coral reefs as they grow. Few studies have attempted to measure at what distances from nursery habitats these fish migrations (connectivity) cease to exist and how the abundance, biomass and proportion of nursery species change on coral reefs along distance gradients away from nursery areas. The present study examines seascape spatial arrangement, including distances between habitats, and its con-sequences on connectivity within a tropical seascape in Mozambique using a seascape ecology approach. Fish and habitat surveys were undertaken in 2016/2017 and a thematic habitat map was created in ArcGIS, where cover and distances between habitat patches were calculated. Distance to mangroves and seagrasses were significant predictors for abundance and biomass of most nursery species. The proportions of nursery species were highest in the south of the archipelago, where mangroves were present and decreased with distance to nurseries (mangroves and seagrasses). Some nursery species were absent on reef sites farthest from nursery habitats, at 80 km from mangroves and at 12 km from seagrass habitats. The proportion of nursery/non-nursery snapper and parrotfish species, as well as abundance and biomass of seagrass nursery species abruptly declined at 8 km from seagrass habitats, indicating a threshold distance at which migrations may cease. Additionally, reefs isolated by large stretches of sand and deep water had very low abundances of several nursery species despite being within moderate distances from nursery habitats. This highlights the importance of considering the matrix (sand and deep water) as barriers for fish migration
Thresholds in seascape connectivity: the spatial arrangement of nursery habitats structure fish communities on nearby reefs
Ecosystems are linked by the movement of organisms across habitat boundaries and the arrangement of habitat patches can affect species abundance and composition. In tropical seascapes many coral reef fishes settle in adjacent habitats and undergo ontogenetic habitat shifts to coral reefs as they grow. Few studies have attempted to measure at what distances from nursery habitats these fish migrations (connectivity) cease to exist and how the abundance, biomass and proportion of nursery species change on coral reefs along distance gradients away from nursery areas. The present study examines seascape spatial arrangement, including distances between habitats, and its consequences on connectivity within a tropical seascape in Mozambique using a seascape ecology approach. Fish and habitat surveys were undertaken in 2016/2017 and a thematic habitat map was created in ArcGIS, where cover and distances between habitat patches were calculated. Distance to mangroves and seagrasses were significant predictors for abundance and biomass of most nursery species. The proportions of nursery species were highest in the south of the archipelago, where mangroves were present and decreased with distance to nurseries (mangroves and seagrasses). Some nursery species were absent on reef sites farthest from nursery habitats, at 80 km from mangroves and at 12 km from seagrass habitats. The proportion of nursery/non-nursery snapper and parrotfish species, as well as abundance and biomass of seagrass nursery species abruptly declined at 8 km from seagrass habitats, indicating a threshold distance at which migrations may cease. Additionally, reefs isolated by large stretches of sand and deep water had very low abundances of several nursery species despite being within moderate distances from nursery habitats. This highlights the importance of considering the matrix (sand and deep water) as barriers for fish migration
Effects of Local and Landscape Factors on Population Dynamics of a Cotton Pest
BACKGROUND: Many polyphagous pests sequentially use crops and uncultivated habitats in landscapes dominated by annual crops. As these habitats may contribute in increasing or decreasing pest density in fields of a specific crop, understanding the scale and temporal variability of source and sink effects is critical for managing landscapes to enhance pest control. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated how local and landscape characteristics affect population density of the western tarnished plant bug, Lygus hesperus (Knight), in cotton fields of the San Joaquin Valley in California. During two periods covering the main window of cotton vulnerability to Lygus attack over three years, we examined the associations between abundance of six common Lygus crops, uncultivated habitats and Lygus population density in these cotton fields. We also investigated impacts of insecticide applications in cotton fields and cotton flowering date. Consistent associations observed across periods and years involved abundances of cotton and uncultivated habitats that were negatively associated with Lygus density, and abundance of seed alfalfa and cotton flowering date that were positively associated with Lygus density. Safflower and forage alfalfa had variable effects, possibly reflecting among-year variation in crop management practices, and tomato, sugar beet and insecticide applications were rarely associated with Lygus density. Using data from the first two years, a multiple regression model including the four consistent factors successfully predicted Lygus density across cotton fields in the last year of the study. CONCLUSIONS/SIGNIFICANCE: Our results show that the approach developed here is appropriate to characterize and test the source and sink effects of various habitats on pest dynamics and improve the design of landscape-level pest management strategies
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