141 research outputs found
Functional aspects of colour processing within the human brain
In a seminal work, Ungerleider and Mishkin (1982) offered substantial evidence that two separate visual pathways â coding what/where-- exist within the primate brain. Recently, human evidence has resulted in the âwhat/whereâ pathways being reconsidered in terms of ventral stream (vision for perception) and dorsal stream (vision for action; Goodale & Milner, 1992). Consistently, many studies have demonstrated that there is an overrepresentation of magnocellular (luminance) information within the dorsal stream; parvocellular input (colour, shape, consistancy) represents the primary source of information for the ventral stream. Although luminance contrast is important in perceiving moving objects, colour discrepancies help the visual system to identify the detailed characteristics of the environment and, subsequently, to prepare the motor system for action. This thesis endeavors to determine the role played by colour, in contrast with luminance, in influencing the programming and control movement production. Using a grasping paradigm and two different luminance conditions (iso-luminance vs. heteroluminance) within two separate experiments (experiment 1 â programming; experiment 2 â online control), we show that chromatic information can be successfully be used by motor circuits to complete the grasping task faultlessly. Although significant temporal delays in terms of reaction time and movement time between colour and luminance processing are identified, the human visual system seems able to fully integrate colour features for action with no significant spatial error cost
Migraine and Gallbladder Motility
Introduction Five (5) hydroxitryptamine (5-HT) selective receptor agonists (triptans) were reported to have gastric motor effects. However, less is known about their role on gallbladder (GB) motility. Aim: Assessment of GB motility in patients treated with orodispersable triptans for migraineâs attacks. Patients and Methods: Out of 112 patients with various forms of migraine who required triptans while having headache attacks, followed-up in our ambulatory service, we have selected 30 patients diagnosed with mild to moderate migraine. These patients include: 15 with aura (3 men, 12 women, mean age=41,8±16,42 years) and 15 without aura (2 men, 13 women, mean age=47,73±18,50 years). Consequently, they had an ejection fraction (EF) of GB which is less than 60% (previously measured in intercritic period by elipsoid ultrasound Dodds method). Furthermore, no record of prokinetic or proton pump inhibitor treatments, gastric surgery, gallstones, collagen or thyroid disease, diabetes mellitus, cardiac, liver, kidney failure or cancer disease was recorded. The measurements of the GB were made while having a migraine attack, before and in every 15 minutes till 90 minutes. This was after receiving 5 mg of orodispersable zolmitriptan. Results: There are no statistical significant difference between initially EF of the two groups (p=0,8190). Patients with migraine with aura showed a mean EF=42,53±4,31% before therapy. After therapy, the mean EF improved significantly: 48,80±3,23% (p=0,0001). Patients having migraine without aura displayed an initially mean EF=42,53±3,27%. In addition, they had a very statistically significant response to therapy with important improvement of EF to 61,47±7,07% (p<0,0001). Conclusions: 5HT selective receptor agonists increased GB motility, in migraine attacks with a response above the cut-off range of EF, in patients having migraine without aura
Ein Beispiel der spÀteisenzeitlichen Orlea-Maglavit Fibel aus der Imre Pongråcz Sammlung
Imre Pongråcz (1849-1903) war Major bei der HonvÚd Infanetrie und MilitÀrkommandant des
OrÈova Hafens. WĂ€hrend seines Lebens sammelte er ĂŒber 6000 AntiquitĂ€ten, die ĂŒberwiegend vom
rechten Donau-Ufer, aus heutigem Serbien, stammen und von den sog. âSchatzjĂ€gernâ gesammelt
wurden. Immerhin fehlt fĂŒr die meisten Objekte aus der Sammlung eine Fundplatzbestimmung. Ein
bedeutender Bestandteil der Sammlung schlieĂt unterschiedliche Fibeln mit ein, darunter auch etwa
achtzig spĂ€teisenzeitlicher Fibeln. Die hier prĂ€sentierte Fibel gehört dem sog. âOrlea-Maglavitâ Typ,
der wÀhrend der SpÀteisenzeit in Gebieten um die Donau auf dem Balkan vertreten war. Obwohl einige
âOrlea-Maglavitâ Fibeln schon veröffentlicht sind, werden im hiesigen Text einige Aspekte (Tragweise,
Geschlechtsbestimmung der FibeltrÀger usw.) angesprochen, die bisher ungeklÀrt blieben
Speed factors computed for pumping schedules in Water Distribution Networks: DDA versus PDA formulations
This paper focuses on a methodology allowing to derive the pumping schedule in Water Distribution Networks (WDN), upon a time dependent water demand. The selected test case is a previously studied WDN. Two pumping algorithms give different pumping rules. By solving the nonlinear system of equations, consisting of energy balance equations, mass balance equations and pumping rules, one gets the pumps speed factors. Solutions attached to the Pressure Driven Analysis (PDA) correspond to energy and cost savings, with respect to the solutions given by the Demand Driven Analysis (DDA). The methodology described in this paper is simple and rapid, but the iterative numerical method used to solve the system of equations is highly dependent on the starting guess
Experimental test rig designed to analyse pumping station operation controlled by pressure at different key points
The operation of pumps within a pumping station can be controlled by the Pressure Set Point (PSP) value compared to the reading of a pressure sensor placed either at the exit of the pumping station, on the main discharge pipe (classical PSP method), or at a critical/monitoring point within the water distribution network (termed further as remote-control PSP method). We designed and built an experimental test rig, allowing to study both control methods, in the attempt to check the advantage of the remote-control PSP method, with respect to the classical PSP method, since governing equations show that they are equivalent. The design relies on the theoretical approach and numerical results presented within this paper
Localizations at infinity and essential spectrum of quantum Hamiltonians: I. General theory
We isolate a large class of self-adjoint operators H whose essential spectrum
is determined by their behavior at large x and we give a canonical
representation of their essential spectrum in terms of spectra of limits at
infinity of translations of H. The configuration space is an arbitrary abelian
locally compact not compact group.Comment: 63 pages. This is the published version with several correction
Beyond Geo-localization: Fine-grained Orientation of Street-view Images by Cross-view Matching with Satellite Imagery
Street-view imagery provides us with novel experiences to explore different
places remotely. Carefully calibrated street-view images (e.g. Google Street
View) can be used for different downstream tasks, e.g. navigation, map features
extraction. As personal high-quality cameras have become much more affordable
and portable, an enormous amount of crowdsourced street-view images are
uploaded to the internet, but commonly with missing or noisy sensor
information. To prepare this hidden treasure for "ready-to-use" status,
determining missing location information and camera orientation angles are two
equally important tasks. Recent methods have achieved high performance on
geo-localization of street-view images by cross-view matching with a pool of
geo-referenced satellite imagery. However, most of the existing works focus
more on geo-localization than estimating the image orientation. In this work,
we re-state the importance of finding fine-grained orientation for street-view
images, formally define the problem and provide a set of evaluation metrics to
assess the quality of the orientation estimation. We propose two methods to
improve the granularity of the orientation estimation, achieving 82.4% and
72.3% accuracy for images with estimated angle errors below 2 degrees for CVUSA
and CVACT datasets, corresponding to 34.9% and 28.2% absolute improvement
compared to previous works. Integrating fine-grained orientation estimation in
training also improves the performance on geo-localization, giving top 1 recall
95.5%/85.5% and 86.8%/80.4% for orientation known/unknown tests on the two
datasets.Comment: This paper has been accepted by ACM Multimedia 2022. The version
contains additional supplementary material
Spreadsheet solution for the computation of the mean wind speed and turbulence intensity profiles according to the Romanian standard
The presented paper focuses on the computation of the mean wind speed and turbulence intensity profiles for all the cities from Romania. The calculation of both, the mean wind speed profile and the turbulence intensity profile, had as mathematical support the equations presented in the Romanian design standard for wind action CR 1-1-4/2012. The main objective of this paper was to provide a tool for the computation of the two wind action features. This method was based on creating a spreadsheet in Excel with which, in just a few seconds, a user could correctly obtain the two wind characteristics. This Excel dashboard can be used as a teaching material for students as well as input data for structural design engineers in the process of modelling and observing the behaviour of a building excited by wind action on a particular city in Romania
Modern leadership communication and strategic lobbying
In the contemporary day, leadership communication has transcended conventional
mediums and now encompasses a wide array of digital channels, including social media platforms,
virtual environments, and dynamic narrative techniques. Successful leaders use these strategies to
actively involve stakeholders, establish confidence, and effectively communicate a captivating
vision. Strategic lobbying encompasses the practice of exerting influence on decision-makers in
order to alter laws and regulations in a manner that aligns with the aims of an organization. This
study explores the confluence of these approaches, illustrating how leaders use persuasive
communication tactics to effectively advance lobbying initiatives. This study examines the complex
techniques used by contemporary leaders, drawing on case studies from several businesses and
political environments. This study examines the utilization of personal branding, story construction,
and communication proficiency by individuals to establish coalitions, generate grassroots backing,
and negotiate intricate regulatory frameworks. Moreover, it highlights the ethical aspects of this
association, placing emphasis on the significance of openness and conscientious promotion. This
article provides insights for leaders, policymakers, and researchers who are interested in
understanding and using the potential of contemporary leadership communication and strategic
lobbying to accomplish corporate and societal goals in a time when leadership and advocacy are
closely connected
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