345 research outputs found
Investigation of the Galactic Magnetic Field with Ultra-High Energy Cosmic Rays
We present a method to correct for deflections of ultra-high energy cosmic
rays in the galactic magnetic field. We perform these corrections by simulating
the expected arrival directions of protons using a parameterization of the
field derived from Faraday rotation and synchrotron emission measurements. To
evaluate the method we introduce a simulated astrophysical scenario and two
observables designed for testing cosmic ray deflections. We show that protons
can be identified by taking advantage of the galactic magnetic field pattern.
Consequently, cosmic ray deflection in the galactic field can be verified
experimentally. The method also enables searches for directional correlations
of cosmic rays with source candidates.Comment: 12 pages, 3 figures, presented at the Eur. Phys. Soc. Conf. on High
Energy Physics, Jul. 2015, Vienna, Austria, and the 34th Intern. Cosmic Ray
Conf., Jul. 2015, The Hague, The Netherland
Cosmic ray propagation with CRPropa 3
Solving the question of the origin of ultra-high energy cosmic rays (UHECRs)
requires the development of detailed simulation tools in order to interpret the
experimental data and draw conclusions on the UHECR universe. CRPropa is a
public Monte Carlo code for the galactic and extragalactic propagation of
cosmic ray nuclei above eV, as well as their photon and neutrino
secondaries. In this contribution the new algorithms and features of CRPropa 3,
the next major release, are presented. CRPropa 3 introduces time-dependent
scenarios to include cosmic evolution in the presence of cosmic ray deflections
in magnetic fields. The usage of high resolution magnetic fields is facilitated
by shared memory parallelism, modulated fields and fields with heterogeneous
resolution. Galactic propagation is enabled through the implementation of
galactic magnetic field models, as well as an efficient forward propagation
technique through transformation matrices. To make use of the large Python
ecosystem in astrophysics CRPropa 3 can be steered and extended in Python.Comment: 16th International workshop on Advanced Computing and Analysis
Techniques in physics research (ACAT 2014) proceedings, 6 pages, 6 figure
Mental and emotional representations of “weight loss”: free-word association networks in members of bariatric surgery-related social media communities
Background: Mindset and communication barriers may hinder the acceptance of bariatric surgery (BS) by the eligible patient population.
Objectives: To improve the understanding of expectations, opinions, emotions, and attitudes toward weight loss among patients with obesity.
Setting: Switzerland, Germany, Austria.
Methods: Survey data collected from BS-related social media communities (n = 1482). Participants were asked to write 5 words that first came to their mind about "weight loss," and to select 2 emotions, which best described their corresponding feelings. Demographic and obesity-related data were collected. Cognitive representations were constructed based on the co-occurrence network of associations, using validated data-driven methodology.
Results: Respondents were Caucasian (98%), female (94%), aged 42.5 ± 10.1 years, current/highest lifetime body mass index = 36.9 ± 9/50.7 ± 8.7 kg/m2. The association network analysis revealed the following 2 cognitive modules: benefit-focused (health, attractiveness, happiness, agility) and procedure-focused (effort, diet, sport, surgery). Patients willing to undergo BS were more benefit-focused (odds ratio [OR] = 2.4, P = .02) and expressed more "hope" (OR = 142, P < .001). History of BS was associated with higher adherence to the procedure-focused module (OR = 2.3, P < .001), and with increased use of the emotions "gratitude" (OR = 107, P < .001), "pride" (OR = 15, P < .001), and decreased mention of "hope" (OR = .03, P < .001).
Conclusion: Patients with obesity in our study tend to think about weight loss along 2 cognitive schemes, either emphasizing its expected benefits or focusing on the process of achieving it. Benefit-focused respondents were more likely to consider BS, and to express hope rather than gratitude or pride. Novel communication strategies may increase the acceptance of BS by incorporating weight loss-related cognitive and emotional content stemming from patients' free associations
A field study of data analysis exercises in a bachelor physics course using the internet platform VISPA
Bachelor physics lectures on particle physics and astrophysics were
complemented by exercises related to data analysis and data interpretation at
the RWTH Aachen University recently. The students performed these exercises
using the internet platform VISPA, which provides a development environment for
physics data analyses. We describe the platform and its application within the
physics course, and present the results of a student survey. The students
acceptance of the learning project was positive. The level of acceptance was
related to their individual preference for learning with a computer.
Furthermore, students with good programming skills favor working individually,
while students who attribute themselves having low programming abilities favor
working in teams. The students appreciated approaching actual research through
the data analysis tasks.Comment: 21 pages, 8 figures, 1 table, for the internet platform VISPA see
http://vispa.physik.rwth-aachen.d
Проблемы научно-технического прогресса в бурении скважин: сборник докладов Всероссийской научно-технической конференции с международным участием , посвященной 60-летию кафедры бурения скважин, Томск, 2014 г.
В материалах сборника представлены результаты исследований научных работников по важным вопросам бурения геологоразведочных, технических, нефтяных и газовых скважин, проведения горно-разведочных выработок: разрушение горных пород, упрочнение породоразрушающего инструмента, скважинная гидродобыча руды, подземное выщелачивание урана, новые подходы по изучению буровых растворов, цементирование обсадных колонн, поиск новых путей получения информации с забоя в процессе бурения; даны решения ряда актуальных вопросов при проведении горноразведочных выработок
Scientific Opinion addressing the state of the science on risk assessment of plant protection products for in-soil organisms
Following a request from EFSA, the Panel on Plant Protection Products and their Residues developed an opinion on the science behind the risk assessment of plant protection products for in-soil organisms. The current risk assessment scheme is reviewed, taking into account new regulatory frameworks and scientific developments. Proposals are made for specific protection goals for in-soil organisms being key drivers for relevant ecosystem services in agricultural landscapes such as nutrient cycling, soil structure, pest control and biodiversity. Considering the time-scales and biological processes related to the dispersal of the majority of in-soil organisms compared to terrestrial non-target arthropods living above soil, the Panel proposes that in-soil environmental risk assessments are made at in- and off-field scale considering field boundary levels. A new testing strategy which takes into account the relevant exposure routes for in-soil organisms and the potential direct and indirect effects is proposed. In order to address species recovery and long-term impacts of PPPs, the use of population models is also proposed
An update on equine postoperative ileus: Definitions, pathophysiology and management.
Postoperative ileus (POI) is a serious condition which any horse undergoing abdominal surgery is at risk of developing, leading to increased hospitalisation time and resulting costs. Advances in the understanding of the development of equine POI are mainly based on human and rodent literature, where manipulation-induced inflammation has been identified as a key trigger, with activation of resident muscularis externa macrophages playing a crucial role in the pathophysiology. Despite many pharmacological trials in all species, there is no single completely successful treatment for POI, highlighting that the condition is multifactorial in cause and requires a multimodal approach to minimise its incidence. This article is protected by copyright. All rights reserved
Search for heavy resonances decaying to two Higgs bosons in final states containing four b quarks
A search is presented for narrow heavy resonances X decaying into pairs of Higgs bosons (H) in proton-proton collisions collected by the CMS experiment at the LHC at root s = 8 TeV. The data correspond to an integrated luminosity of 19.7 fb(-1). The search considers HH resonances with masses between 1 and 3 TeV, having final states of two b quark pairs. Each Higgs boson is produced with large momentum, and the hadronization products of the pair of b quarks can usually be reconstructed as single large jets. The background from multijet and t (t) over bar events is significantly reduced by applying requirements related to the flavor of the jet, its mass, and its substructure. The signal would be identified as a peak on top of the dijet invariant mass spectrum of the remaining background events. No evidence is observed for such a signal. Upper limits obtained at 95 confidence level for the product of the production cross section and branching fraction sigma(gg -> X) B(X -> HH -> b (b) over barb (b) over bar) range from 10 to 1.5 fb for the mass of X from 1.15 to 2.0 TeV, significantly extending previous searches. For a warped extra dimension theory with amass scale Lambda(R) = 1 TeV, the data exclude radion scalar masses between 1.15 and 1.55 TeV
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