1,110 research outputs found
Atmospheric effects of volcanic eruptions as seen by famous artists and depicted in their paintings
International audiencePaintings created by famous artists, representing sunsets throughout the period 1500?1900, provide proxy information on the aerosol optical depth following major volcanic eruptions. This is supported by a statistically significant correlation coefficient (0.8) between the measured red-to-green ratios of a few hundred paintings and the dust veil index. A radiative transfer model was used to compile an independent time series of aerosol optical depth at 550 nm corresponding to Northern Hemisphere middle latitudes during the period 1500?1900. The estimated aerosol optical depths range from 0.05 for background aerosol conditions, to about 0.6 following the Tambora and Krakatau eruptions and cover a period practically outside of the instrumentation era
Four-dimensional distribution of the 2010 Eyjafjallajökull volcanic cloud over Europe observed by EARLINET
© Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License.The eruption of the Icelandic volcano Eyjafjallaj ökull in April-May 2010 represents a "natural experiment" to study the impact of volcanic emissions on a continental scale. For the first time, quantitative data about the presence, altitude, and layering of the volcanic cloud, in conjunction with optical information, are available for most parts of Europe derived from the observations by the European Aerosol Research Lidar NETwork (EARLINET). Based on multi-wavelength Raman lidar systems, EARLINET is the only instrument worldwide that is able to provide dense time series of high-quality optical data to be used for aerosol typing and for the retrieval of particle microphysical properties as a function of altitude. In this work we show the four-dimensional (4-D) distribution of the Eyjafjallajökull volcanic cloud in the troposphere over Europe as observed by EARLINET during the entire volcanic event (15 April-26 May 2010). All optical properties directly measured (backscatter, extinction, and particle linear depolarization ratio) are stored in the EARLINET database available at www.earlinet.org. A specific relational database providing the volcanic mask over Europe, realized ad hoc for this specific event, has been developed and is available on request at www.earlinet.org. During the first days after the eruption, volcanic particles were detected over Central Europe within a wide range of altitudes, from the upper troposphere down to the local planetary boundary layer (PBL). After 19 April 2010, volcanic particles were detected over southern and south-eastern Europe. During the first half of May (5-15 May), material emitted by the Eyjafjallajökull volcano was detected over Spain and Portugal and then over the Mediterranean and the Balkans. The last observations of the event were recorded until 25 May in Central Europe and in the Eastern Mediterranean area. The 4-D distribution of volcanic aerosol layering and optical properties on European scale reported here provides an unprecedented data set for evaluating satellite data and aerosol dispersion models for this kind of volcanic events.Peer reviewe
What Does It Take: The Roles, Responsibilities, and Fidelity to Implement a Physical Activity in Public HealthTraining
Cooperative Extension Service (Extension) Agents are tasked with incorporating physical activity promotion in their work. Physical activity training interventions rarely report specific structures (dose, content) and measures (fidelity, resource cost). The study’s purpose was to evaluate the feasibility and resource costs of Physical Activity in Cooperative Extension (PACE), a training to increase physical activity in public health competency. PACE is a virtual, 9-week, 18-hour general capacity-building training based on the Interactive Systems Framework. Fidelity was calculated as the proportion of objectives delivered as intended and total time to deliver core components. Resource cost was calculated as the time spent on each implementation strategy and responsibility and total time spent delivering PACE. Fidelity was 93% (39/42 planned objectives delivered as intended). PACE required 183 hours to implement, with session delivery (45 hours) and participant communication (40 hours) requiring the most time. Overall, time spent included 37 hours per delivery team member and 18 hours per PACE participant. The personnel time spent was within the standard time spent on other Extension training protocols and perceived as feasible. Fidelity to session components was high and easy to track. Future work should determine the scalability and sustainability of PACE within Extension nationally
Move More, Sit Less: Applying the Physical Activity Guidelines for Americans to Extension Programs
Extension enhances the lives of Americans by translating research-based information related to existing needs into programming that is practical and accessible to the general public. Evidence clearly indicates that physical activity is correlated to positive health outcomes, but despite this conclusion, the majority of Americans do not meet the recommendations for physical activity. The 2nd Edition of the Physical Activity Guidelines for Americans provides guidance for Extension professionals to implement physical activity interventions. We recommend training and technical assistance strategies based on the Interactive Systems Framework to integrate physical activity promotion into all Extension areas
Shifts in Maritime Trade Routes as a Result of Red Sea Shipping Crisis Detected in TROPOMI NO2 Data
Observations from space-borne spectrometers have been lately used to quantify shipping emissions of nitrogen oxides (ΝΟΧ). Here we present a method that enhances the shipping signal of NO2 TROPOspheric MOnitoring Instrument (TROPOMI) satellite sensor observations in order to assess the impact of the Red Sea ship attacks on NO2 levels in three important shipping routes along the Red Sea, the Cape of Good Hope, and the Gibraltar Strait. Major shipping carriers, sailing usually via the Red Sea, have responded to the attacks by transiting their fleet around the African continent. The shipping signal from TROPOMI declines by ∼55\% in the Red Sea and ∼15\% in the Gibraltar Strait while an increase of ∼40\% is found off the South African coast between January–June 2024 and the same period in 2023. These changes correlate well with vessel statistics, demonstrating the ability to track abrupt changes in NO2 shipping levels with satellite measurements
Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy
Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA
Unifying Multi-State Efforts Through a Nationally Coordinated Extension Diabetes Program
The Cooperative Extension System translates research to practice and “brings the University to the people” throughout the U.S. However, the system suffers from program duplication and is challenged to scale-out effective programs. One program, Dining with Diabetes (DWD), stands out for its dissemination to multiple states. DWD is a community-based program aimed at improving diabetes management, nutrition, and physical activity behaviors. DWD was coordinated through a national working group and implemented by state Extension systems. A pragmatic, quasi-experimental study was conducted to determine the effectiveness of the national coordination model and the overall impact of DWD. Four states reported data representing 355 DWD participants. Significant differences were found in diabetes management behaviors and knowledge from pre to post- program. However, there were challenges with data analysis due to state differences in data management. We detail the transition from one state to a national workgroup, strengths and challenges of the national model, and implications for other Extension programs
The evolution of synoptic ozone anomalies during the European Arctic Stratospheric Ozone Experiment in winter 1991/1992
The evolution of ozone anomalies over the middle and high latitudes of the Northern Hemisphere during the winter 1991-1992 is studied in this work. The largest monthly mean negative deviations in the middle latitudes of the Northern Hemisphere were about 10 percent in November and December, and up to 20 percent in January, February, and March over Eurasian territories, and much smaller over the Canadian sector. At the end of January, on individual days, total ozone values of 190-210 D.U. were observed over Eastern Europe and European part of Russia, that is 40-45 percent below normal. On the whole, the 1991-1992 winter was one of the most anomalous over all the period of ozone observations. Finally, an attempt is made to quantify the contribution of transport in the ozone layer changes over Europe during this period
Oxaliplatin- or irinotecan-based chemotherapy for metastatic colorectal cancer in the elderly
The impact of high-dose methotrexate on intracellular 6-mercaptopurine disposition during interval therapy of childhood acute lymphoblastic leukemia
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