What can be Concluded About what Types of Models from Experiments Using Response Probability as a Dependent Variable

1975 ◽  
Author(s):  
Geoffrey R. Loftus
Keyword(s):  
Response Probability

scholarly journals The Application of Dynamic Uncertain Causality Graph Based Diagnosis and Treatment Unification Model in the Intelligent Diagnosis and Treatment of Hepatitis B

Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1185
Author(s):  
Nan Deng ◽  
Qin Zhang
Keyword(s):  
Hepatitis B ◽  
Response Probability ◽  
Logic Gates ◽  
Current Treatment ◽  
Subsequent Treatment ◽  
Diagnosis And Treatment ◽  
Treatment Model ◽  
Treatment Scheme ◽  
Treatment Plans ◽  
Dynamic Uncertain Causality Graph

Although hepatitis B is widespread, it is hard to cure. This paper presents a new and more accurate model for the diagnosis and treatment of hepatitis B. Based on previous research, the diagnosis and treatment modes were combined into one. By adding more influencing factors and risk factors, the overall diagnosis and treatment model will be further expanded, and a richer and more detailed overall diagnosis and treatment model will be constructed. Reverse logic gates are used in the model to improve the accuracy of the treatment planning. The new unified model is more accurate in subdividing diagnosis results, and it is more flexible and accurate in providing dynamic treatment plans. The prediction process and the static diagnosis process of the model are symmetric, and the related sub-graph is symmetric in structure. In addition, an algorithm for predicting the response probability of treatment scheme is developed, so as to predict the subsequent treatment effects of the current treatment scheme, such as the probability of drug resistance. The results show that this method is more accurate than other available systems, and it has encouraging diagnostic accuracy and effectiveness, which provides a promising help for doctors in diagnosing hepatitis B.

Computer Simulation of the Responses of Human Motoneurons to Composite 1A EPSPS: Effects of Background Firing Rate

1997 ◽  
Vol 77 (1) ◽  
pp. 405-420 ◽  
Author(s):  
Kelvin E. Jones ◽  
Parveen Bawa
Keyword(s):  
Computer Simulation ◽  
Firing Rate ◽  
Time Course ◽  
Current Model ◽  
Response Probability ◽  
Muscle Spindles ◽  
Excitatory Postsynaptic Potential ◽  
Biophysical Properties ◽  
Rhythmic Firing ◽  
The Relationship

Jones, Kelvin E. and Parveen Bawa. Computer simulation of the responses of human motoneurons to composite 1A EPSPS: effects of background firing rate. J. Neurophysiol. 77: 405–420, 1997. Two compartmental models of spinal alpha motoneurons were constructed to explore the relationship between background firing rate and response to an excitatory input. The results of these simulations were compared with previous results obtained from human motoneurons and discussed in relation to the current model for repetitively firing human motoneurons. The morphologies and cable parameters of the models were based on two type-identified cat motoneurons previously reported in the literature. Each model included five voltage-dependent channels that were modeled using Hodgkin-Huxley formalism. These included fast Na+ and K+ channels in the initial segment and fast Na+ and K+ channels as well as a slow K+ channel in the soma compartment. The density and rate factors for the slow K+ channel were varied until the models could reproduce single spike AHP parameters for type-identified motoneurons in the cat. Excitatory synaptic conductances were distributed along the equivalent dendrites with the same density described for la synapses from muscle spindles to type-identified cat motoneurons. Simultaneous activation of all synapses on the dendrite resulted in a large compound excitatory postsynaptic potential (EPSP). Brief depolarizing pulses injected into a compartment of the equivalent dendrite resulted in pulse potentials (PPs), which resembled the compound EPSPs. The effects of compound EPSPs and PPs on firing probability of the two motoneuron models were examined during rhythmic firing. Peristimulus time histograms, constructed between the stimulus and the spikes of the model motoneuron, showed excitatory peaks whose integrated time course approximated the time course of the underlying EPSP or PP as has been shown in cat motoneurons. The excitatory peaks were quantified in terms of response probability, and the relationship between background firing rate and response probability was explored. As in real human motoneurons, the models exhibited an inverse relationship between response probability and background firing rate. The biophysical properties responsible for the relationship between response probability and firing rate included the shapes of the membrane voltage trajectories between spikes and nonlinear changes in PP amplitude during the interspike interval at different firing rates. The results from these simulations suggest that the relationship between response probability and background firing rate is an intrinsic feature of motoneurons. The similarity of the results from the models, which were based on the properties of cat motoneurons, and those from human motoneurons suggests that the biophysical properties governing rhythmic firing in human motoneurons are similar to those of the cat.

scholarly journals Phase II Evaluation of Sorafenib in Advanced and Metastatic Squamous Cell Carcinoma of the Head and Neck: Southwest Oncology Group Study S0420

2010 ◽  
Vol 28 (20) ◽  
pp. 3330-3335 ◽  
Author(s):  
Stephen K. Williamson ◽  
James Moon ◽  
Chao H. Huang ◽  
Perry P. Guaglianone ◽  
Michael LeBlanc ◽  
...  
Keyword(s):  
Overall Survival ◽  
Squamous Cell Carcinoma ◽  
Adverse Events ◽  
Cell Carcinoma ◽  
Head And Neck ◽  
Phase Ii ◽  
Single Agent ◽  
Response Probability ◽  
Oncology Group ◽  
Southwest Oncology Group

Purpose We conducted a phase II trial to evaluate the efficacy and safety of single-agent sorafenib in chemotherapy-naïve patients with metastatic or recurrent squamous cell carcinoma of the head and neck (SCCHN). The primary end point was response probability (ie, confirmed complete and partial response [PR]). Patients and Methods Chemotherapy-naïve patients with metastatic, persistent, or recurrent SCCHN who received one induction or fewer or received an adjuvant chemotherapy regimen, who had adequate organ function, and who had a performance status ≤ 1 were eligible. Sorafenib was administered orally at 400 mg twice daily on a continuous basis in 28-day cycles. Responses were evaluated according to RECIST (Response Evaluation Criteria in Solid Tumors). Results Sorafenib was generally well tolerated. Of the 41 eligible patients assessed for adverse events, one experienced a grade 4 adverse event as a result of an asymptomatic pulmonary embolus. The most common grades 2 to 3 adverse events were fatigue, anorexia, stomatitis/oral pain, abdominal pain, hand-foot syndrome, weight loss, and hypertension. There was one confirmed PR and two unconfirmed PRs. The estimated confirmed response probability was 2% (95% CI, 0% to 13%). The estimated median progression-free survival was 4 months (95% CI, 2 to 4 months), and the estimated median overall survival was 9 months (95% CI, 7 to 14 months). Conclusion Sorafenib was well tolerated. Although response was poor, progression-free and overall survival times compare favorably with previous Southwest Oncology Group, phase II, single-agent trials.

scholarly journals Detection of tactile inputs in the rat vibrissa pathway

2012 ◽  
Vol 108 (2) ◽  
pp. 479-490 ◽  
Author(s):  
Douglas R. Ollerenshaw ◽  
Bilal A. Bari ◽  
Daniel C. Millard ◽  
Lauren E. Orr ◽  
Qi Wang ◽  
...  
Keyword(s):  
High Speed ◽  
Barrel Cortex ◽  
Sensory Information ◽  
Reaction Times ◽  
Response Probability ◽  
Relevant Information ◽  
Relative Strength ◽  
Spatiotemporal Representation ◽  
Induced Motion ◽  
Electrophysiological Findings

The rapid detection of sensory inputs is crucial for survival. Sensory detection explicitly requires the integration of incoming sensory information and the ability to distinguish between relevant information and ongoing neural activity. In this study, head-fixed rats were trained to detect the presence of a brief deflection of their whiskers resulting from a focused puff of air. The animals showed a monotonic increase in response probability and a decrease in reaction time with increased stimulus strength. High-speed video analysis of whisker motion revealed that animals were more likely to detect the stimulus during periods of reduced self-induced motion of the whiskers, thereby allowing the stimulus-induced whisker motion to exceed the ongoing noise. In parallel, we used voltage-sensitive dye (VSD) imaging of barrel cortex in anesthetized rats receiving the same stimulus set as those in the behavioral portion of this study to assess candidate codes that make use of the full spatiotemporal representation and to compare variability in the trial-by-trial nature of the cortical response and the corresponding variability in the behavioral response. By application of an accumulating evidence framework to the population cortical activity measured in separate animals, a strong correspondence was made between the behavioral output and the neural signaling, in terms of both the response probabilities and the reaction times. Taken together, the results here provide evidence for detection performance that is strongly reliant on the relative strength of signal versus noise, with strong correspondence between behavior and parallel electrophysiological findings.

Components of responses of a population of DSCT neurons to muscle stretch and contraction

1989 ◽  
Vol 61 (2) ◽  
pp. 456-465 ◽  
Author(s):  
C. E. Osborn ◽  
R. E. Poppele
Keyword(s):  
Time Course ◽  
Functional Organization ◽  
Afferent Fiber ◽  
Response Probability ◽  
Principal Component ◽  
Response Patterns ◽  
Afferent Pathways ◽  
Hindlimb Muscles ◽  
Spinocerebellar Tract ◽  
And Cluster Analysis

1. Impulse activity of 264 units of the dorsal spinocerebellar tract (DSCT) was recorded during random contraction or stretch in hindlimb muscles. Contractions were evoked in either the isolated gastrocnemius-soleus (GS) muscles or the intact limb during crossed-extensor reflexes; stretches were applied to the isolated GS. 2. The time course of poststimulus changes in spike activity of DSCT neurons was determined from the response probability function (RPF; Ref. 15). These data were analyzed using principal component and cluster analysis to group the responses according to the RPF waveforms. 3. The responses to each type of stimulus displayed a remarkable similarity in time course, regardless of the type of stimulus used. The responses were also similar to those observed previously during single shock nerve stimulation (14). 4. The most reasonable explanation for these results is that the time course of excitability changes in DSCT neurons is determined less by particular types of receptors or patterns of afferent fiber activity than by the circuitry and afferent pathways impinging on the neurons of the DSCT. 5. The functional organization of DSCT suggested by these results includes a wide divergence from sensory receptors along polysynaptic pathways to DSCT neurons and considerable convergence onto each neuron from a diversity of receptors. Individual DSCT cells may respond to stimuli with one of a few stereo-typical response patterns yet the distribution of those patterns among the units of the DSCT population may be unique for each stimulus.

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