scholarly journals Learning In Spike Trains: Estimating Within-Session Changes In Firing Rate Using Weighted Interpolation

2016 ◽  
Author(s):  
Greg Jensen ◽  
Fabian Muñoz ◽  
Vincent P. Ferrera

AbstractThe electrophysiological study of learning is hampered by modern procedures for estimating firing rates: Such procedures usually require large datasets, and also require that included trials be functionally identical. Unless a method can track the real-time dynamics of how firing rates evolve, learning can only be examined in the past tense. We propose a quantitative procedure, called ARRIS, that can uncover trial-by-trial firing dynamics. ARRIS provides reliable estimates of firing rates based on small samples using the reversible-jump Markov chain Monte Carlo algorithm. Using weighted interpolation, ARRIS can also provide estimates that evolve over time. As a result, both real-time estimates of changing activity, and of task-dependent tuning, can be obtained during the initial stages of learning.

Author(s):  
Erida Gjini

AbstractThe SARS-CoV-2 epidemic is one of the biggest challenges healthcare systems worldwide have ever had to face. To curb transmission many countries have adopted social distancing measures and travel restrictions. Estimating the effect of these measures in each context is challenging and requires mathematical models of the transmission dynamics. Projections for the future course of the epidemic strongly rely on model predictions and accurate representation of real-time data as they accumulate. Here I develop an SEIR modeling framework for Covid-19, to evaluate reported cases and fatalities, and to enable forecasting using evidence-based Bayesian parameter estimation. This Bayesian framework offers a tool to parametrize real-time dynamics of Covid-19 cases, and explore the effect of control as it unfolds in any setting. I apply the model to Covid-19 data from Albania, where drastic control measures were put in place already on the day of the first confirmed case. Evaluating the dynamics of reported cases 9-31 March 2020, I estimate parameters and make preliminary projections. Three weeks into the measures, Albanian data already indicate a strong signature of more than 40% transmission reduction, and lend support to a progressively increasing effect of control measures rather than a static one. In the Albanian setting, the model and data match well, projecting the peak of the outbreak may be around 5-15 April, and be contained within 300 active confirmed cases if control continues with the same trend. This framework can be used to understand the quantitative effects of different control measures in real-time, and inform adaptive intervention for success in other settings.


Author(s):  
Alan S. Rudolph ◽  
Ronald R. Price

We have employed cryoelectron microscopy to visualize events that occur during the freeze-drying of artificial membranes by employing real time video capture techniques. Artificial membranes or liposomes which are spherical structures within internal aqueous space are stabilized by water which provides the driving force for spontaneous self-assembly of these structures. Previous assays of damage to these structures which are induced by freeze drying reveal that the two principal deleterious events that occur are 1) fusion of liposomes and 2) leakage of contents trapped within the liposome [1]. In the past the only way to access these events was to examine the liposomes following the dehydration event. This technique allows the event to be monitored in real time as the liposomes destabilize and as water is sublimed at cryo temperatures in the vacuum of the microscope. The method by which liposomes are compromised by freeze-drying are largely unknown. This technique has shown that cryo-protectants such as glycerol and carbohydrates are able to maintain liposomal structure throughout the drying process.


2019 ◽  
pp. 135-142
Author(s):  
K. V. Ivanova ◽  
A. M. Lapina ◽  
V. V. Neshataev

The 2nd international scientific conference «Fundamental problems of vegetation classification» took place at the Nikitskiy Botanical Garden (Yalta, Republic of Crimea, Russia) on 15–20 September 2019. There were 56 participants from 33 cities and 43 research organizations in Russia. The conference was mostly focused on reviewing the success in classification of the vegetation done by Russian scientists in the past three years. The reports covered various topics such as classification, description of new syntaxonomical units, geobotanical mapping for different territories and types of vegetation, studies of space-time dynamics of plant communities. The final discussion on the last day covered problems yet to be solved: establishment of the Russian Prodromus and the National archive of vegetation, complications of higher education in the profile of geobotany, and the issue of the data leakage to foreign scientific journals. In conclusion, it was announced that the 3rd conference in Nikitskiy Botanical Garden will be held in 2022.


Author(s):  
Nurit Yaari

How does a theatrical tradition emerge in the fields of dramatic writing and artistic performance? Can a culture, in which theatre played no part in the past, create a theatrical tradition in real time—and how? What was the contribution of classical Greek drama to the evolution of Israeli theatre? How do political and social conditions affect the encounter between cultures—and what role do they play in creating a theatre with a distinctive identity? This book, the first of its kind, attempts to answer these and other questions, by examining the reception of classical Greek drama in the Israeli theatre over the last seventy years. It deals with dramatic and aesthetic issues while analysing translations, adaptations, new writing, mise-en-scène, and ‘post dramatic’ performances of classical Greek drama that were created and staged at key points of the development of Israeli culture amidst fateful political, social, and cultural events in the country’s history.


Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1804
Author(s):  
Dimitar Stanev ◽  
Konstantinos Filip ◽  
Dimitrios Bitzas ◽  
Sokratis Zouras ◽  
Georgios Giarmatzis ◽  
...  

This study aims to explore the possibility of estimating a multitude of kinematic and dynamic quantities using subject-specific musculoskeletal models in real-time. The framework was designed to operate with marker-based and inertial measurement units enabling extensions far beyond dedicated motion capture laboratories. We present the technical details for calculating the kinematics, generalized forces, muscle forces, joint reaction loads, and predicting ground reaction wrenches during walking. Emphasis was given to reduce computational latency while maintaining accuracy as compared to the offline counterpart. Notably, we highlight the influence of adequate filtering and differentiation under noisy conditions and its importance for consequent dynamic calculations. Real-time estimates of the joint moments, muscle forces, and reaction loads closely resemble OpenSim’s offline analyses. Model-based estimation of ground reaction wrenches demonstrates that even a small error can negatively affect other estimated quantities. An application of the developed system is demonstrated in the context of rehabilitation and gait retraining. We expect that such a system will find numerous applications in laboratory settings and outdoor conditions with the advent of predicting or sensing environment interactions. Therefore, we hope that this open-source framework will be a significant milestone for solving this grand challenge.


2021 ◽  
pp. 147612702110120
Author(s):  
Siavash Alimadadi ◽  
Andrew Davies ◽  
Fredrik Tell

Research on the strategic organization of time often assumes that collective efforts are motivated by and oriented toward achieving desirable, although not necessarily well-defined, future states. In situations surrounded by uncertainty where work has to proceed urgently to avoid an impending disaster, however, temporal work is guided by engaging with both desirable and undesirable future outcomes. Drawing on a real-time, in-depth study of the inception of the Restoration and Renewal program of the Palace of Westminster, we investigate how organizational actors develop a strategy for an uncertain and highly contested future while safeguarding ongoing operations in the present and preserving the heritage of the past. Anticipation of undesirable future events played a crucial role in mobilizing collective efforts to move forward. We develop a model of future desirability in temporal work to identify how actors construct, link, and navigate interpretations of desirable and undesirable futures in their attempts to create a viable path of action. By conceptualizing temporal work based on the phenomenological quality of the future, we advance understanding of the strategic organization of time in pluralistic contexts characterized by uncertainty and urgency.


2014 ◽  
Vol 90 (24) ◽  
Author(s):  
Luis Seabra ◽  
Fabian H. L. Essler ◽  
Frank Pollmann ◽  
Imke Schneider ◽  
Thomas Veness

Author(s):  
Ramutis Bansevicius ◽  
Algimantas Cepulkauskas ◽  
Regina Kulvietiene ◽  
Genadijus Kulvietis

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