145 research outputs found
THE COMPLEX USE OF COMPUTER AND VIDEO FOR KINEMATIC STUDIES
The important problem of modern sport is the technical training of sportsmen. A successful solution of this problem is impossible without deep study of the structure of athletes' movements.
The video complex used in our research includes hardware and software programs. The hardware include:
-ordinary computer;
-video camera and videotape-recorder;
-and non-standard equipment (video processor for the transmission of video signals digitally in computer's memory).
The fragments, made in conditions of training or competition, are digitized by means of special video charges, which allow one to convert a video signal into numerical form. All fragments will be converted into files in the AVI format (Video for Windows). It is possible to reproduce these files on the screen of the monitor with the help of the Microsoft Windows universal player-standard program.
It is possible to demonstrate a file once or as a film-ring, frame by frame rewinding and in a freeze-frame.
Stopping a video fragment is accompanied by fixing a frame and stopping the time. A standard program package ensures access to each frame of the video sequence. Consequently, any frame may be put in correspondence to time. This allows one to calculate a phase structure of athletic action and determine cinematic features of sport technique.
For biomechanical studies special attention is paid to the programs for editing photos. Any frame may be copied and inserted in the file of the Microsoft Photo Editor or Microsoft Photo Shop. Each point of this photo will correspond to a pair of coordinates, shown on the screen of the monitor. Having copied several frames in given time intervals, one can define a change of the coordinates of points in dependence upon time.
In this way it is possible to calculate a speed or velocity of motion, and other facts interesting for the researcher. By the way, a standard effects kit allows one to change the brightness, contrast, color to find the position of checkpoints on investigated objects (it may be a body or athletic equipment). One can expose a necessary balance on photos by changing offered parameters in the Preview window or using autobalance, calculated by the computer. A given photo is easy to print.
A series of such photos may be used as a kinogramma and provide the basis for biomechanical calculations.
In order to add graphic elements to a photo use the Paint editor. The offered way of registration allows one to apply practically any study of movement by athletes with pixel accuracy
Non-ergodicity of the motion in three dimensional steep repelling dispersing potentials
It is demonstrated numerically that smooth three degrees of freedom
Hamiltonian systems which are arbitrarily close to three dimensional strictly
dispersing billiards (Sinai billiards) have islands of effective stability, and
hence are non-ergodic. The mechanism for creating the islands are corners of
the billiard domain.Comment: 6 pages, 8 figures, submitted to Chao
Efficiency in a forced contribution threshold public good game
We contrast and compare three ways of predicting efficiency in a forced contribution threshold public good game. The three alternatives are based on ordinal potential, quantal response and impulse balance theory. We report an experiment designed to test the respective predictions and find that impulse balance gives the best predictions. A simple expression detailing when enforced contributions result in high or low efficiency is provided
Sleep oscillation-specific associations with Alzheimer’s disease CSF biomarkers : novel roles for sleep spindles and tau
Background: Based on associations between sleep spindles, cognition, and sleep-dependent memory processing,
here we evaluated potential relationships between levels of CSF Aβ42, P-tau, and T-tau with sleep spindle density
and other biophysical properties of sleep spindles in a sample of cognitively normal elderly individuals.
Methods: One-night in-lab nocturnal polysomnography (NPSG) and morning to early afternoon CSF collection
were performed to measure CSF Aβ42, P-tau and T-tau. Seven days of actigraphy were collected to assess habitual
total sleep time.
Results: Spindle density during NREM stage 2 (N2) sleep was negatively correlated with CSF Aβ42, P-tau and T-tau.
From the three, CSF T-tau was the most significantly associated with spindle density, after adjusting for age, sex and
ApoE4. Spindle duration, count and fast spindle density were also negatively correlated with T-tau levels. Sleep
duration and other measures of sleep quality were not correlated with spindle characteristics and did not modify
the associations between sleep spindle characteristics and the CSF biomarkers of AD.
Conclusions: Reduced spindles during N2 sleep may represent an early dysfunction related to tau, possibly
reflecting axonal damage or altered neuronal tau secretion, rendering it a potentially novel biomarker for early
neuronal dysfunction. Given their putative role in memory consolidation and neuroplasticity, sleep spindles may
represent a mechanism by which tau impairs memory consolidation, as well as a possible target for therapeutic
interventions in cognitive decline
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Community projects: an experimental analysis of a fair implementation process
We define and experimentally test a public provision mechanism that meets three basic ethical requirements and allows community members to influence, via monetary bids, which of several projects is implemented. For each project, participants are assigned personal values, which can be positive or negative. We provide either public or private information about personal values. This produces two distinct public provision games, which are experimentally implemented and analyzed for various projects. In spite of the complex experimental task, participants do not rely on bidding their own personal values as an obvious simple heuristic whose general acceptance would result in fair and efficient outcomes. Rather, they rely on strategic underbidding. Although underbidding is affected by projects’ characteristics, the provision mechanism mostly leads to the implementation of the most efficient project
Safety and Efficacy of Axicabtagene Ciloleucel versus Standard of Care in Patients 65 Years of Age or Older with Relapsed/Refractory Large B-Cell Lymphoma
Purpose: Older patients with relapsed/refractory (R/R) large B-cell lymphoma (LBCL) may be considered ineligible for curative-intent therapy including high-dose chemotherapy with autologous stem-cell transplantation (HDT-ASCT). Here, we report outcomes of a preplanned subgroup analysis of patients >= 65 years in ZUMA-7. Patients and Methods: Patients with LBCL refractory to or relapsed = 65 years were random-ized to axi-cel and SOC, respectively. Median EFS was greater with axi-cel versus SOC (21.5 vs. 2.5 months; median follow-up: 24.3 months; HR, 0.276; descriptive P = 3 adverse events occurred in 94% of axi-cel and 82% of SOC patients. No grade 5 cytokine release syndrome or neurologic events occurred. In the quality-of-life analysis, the mean change in PRO scores from baseline at days 100 and 150 favored axi-cel for EORTC QLQ-C30 Global Health, Physical Functioning, and EQ-5D-5L visual analog scale (descriptive P = 65 and = 65 years with R/R LBCL
Mechanisms of Vasorelaxation
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72633/1/j.1527-3466.1992.tb00249.x.pd
Does time pressure impair performance? An experiment on queueing behavior
Conte A, Scarsini M, Sürücü O. Does time pressure impair performance? An experiment on queueing behavior. Center for Mathematical Economics Working Papers. Vol 538. Bielefeld: Center for Mathematical Economics; 2015.We experimentally explore the effects of time pressure on decision making. Under different time allowance conditions, subjects are presented with a queueing
situation and asked to join one of two queues that differ in length, server speed, and entry fee. The results can be grouped under two main categories. The first one concerns the factors driving customers' decisions in a queueing system. Only a proportion of subjects behave rationally and use the relevant information efficiently. The rest of the subjects seem to adopt a rule of thumb that ignores the
information on server speed and follows the shorter queue. The second category is related to the effects of time pressure on decision performance. A significant
proportion of the population is not affected by time limitations and shows a consistent behavior throughout the treatments. On the other hand, the majority of
subjects' performance is impaired by time limitations. More importantly, this impairment is not due to the stringency of the limitation but mainly due to the
fact that being exposed to a time limitation, even to a loose one, brings along stress and panic, and causes subjects to use time inefficiently
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