Simulating lesion-dependent functional recovery mechanisms

AbstractFunctional recovery after brain damage varies widely and depends on many factors, including lesion site and extent. When a neuronal system is damaged, recovery may occur by engaging residual (e.g., perilesional) components. When damage is extensive, recovery depends on the availability of other intact neural structures that can reproduce the same functional output (i.e., degeneracy). A system’s response to damage may occur rapidly, require learning or both. Here, we simulate functional recovery from four different types of lesions, using a generative model of word repetition that comprised a default premorbid system and a less used alternative system. The synthetic lesions (i) completely disengaged the premorbid system, leaving the alternative system intact, (ii) partially damaged both premorbid and alternative systems, and (iii) limited the experience-dependent plasticity of both. The results, across 1000 trials, demonstrate that (i) a complete disconnection of the premorbid system naturally invoked the engagement of the other, (ii) incomplete damage to both systems had a much more devastating long-term effect on model performance and (iii) the effect of reducing learning capacity within each system. These findings contribute to formal frameworks for interpreting the effect of different types of lesions.

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The method of repairing OHE damaged ancient painted murals based on machine vision

Journal of Computational Methods in Sciences and Engineering ◽

10.3233/jcm-215654 ◽

2021 ◽

pp. 1-15

Author(s):

Hao Li

Keyword(s):

Machine Vision ◽

Two Dimensional ◽

Traditional Methods ◽

Dimensional Image ◽

Two Dimensional Image ◽

Different Types ◽

Damage Data ◽

Incomplete Damage

Traditional mural repair methods only observe the texture of murals when segmenting the repair area, but ignore the extraction of a mural damage data, resulting in incomplete damage crack information. For this reason, the method of repairing the damaged murals based on machine vision is studied. Using machine vision, it can get two-dimensional image of a mural, preprocess the image, extract the damaged data of a mural, and then divide the repair area and repair degree index. According to different types of damage, it can choose the corresponding repair methods to achieve the repair of damaged mural. The results show: Compared with the reference [1] method and reference [2] method, the number of repair points and repair cracks extracted by the proposed method is more than that of the two traditional methods, which can more accurately and comprehensively extract the repair information of murals.

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A novel nerve transection and repair method in mice: histomorphometric analysis of nerves, blood vessels, and muscles with functional recovery

Scientific Reports ◽

10.1038/s41598-020-78481-1 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Jung Il Lee ◽

Anagha A. Gurjar ◽

M. A. Hassan Talukder ◽

Andrew Rodenhouse ◽

Kristen Manto ◽

...

Keyword(s):

Muscle Atrophy ◽

Functional Recovery ◽

Functional Outcomes ◽

Nerve Transection ◽

Histomorphometric Analysis ◽

Sciatic Nerve Transection ◽

Functional Deficit ◽

Reliable Model ◽

Different Types ◽

Branching Index

AbstractPeripheral nerve transection is associated with permanent functional deficit even after advanced microsurgical repair. While it is difficult to investigate the reasons of poor functional outcomes of microsurgical repairs in humans, we developed a novel pre-clinical nerve transection method that allows reliable evaluation of nerve regeneration, neural angiogenesis, muscle atrophy, and functional recovery. Adult male C57BL/6 mice were randomly assigned to four different types of sciatic nerve transection: Simple Transection (ST), Simple Transection & Glue (TG), Stepwise Transection and Sutures (SU), and Stepwise Transection and Glue (STG). Mice were followed for 28 days for sciatic function index (SFI), and sciatic nerves and hind limb muscles were harvested for histomorphological and cellular analyses. Immunohistochemistry revealed more directional nerve fiber growth in SU and STG groups compared with ST and TG groups. Compared to ST and TG groups, optimal neural vessel density and branching index in SU and STG groups were associated with significantly decreased muscle atrophy, increased myofiber diameter, and improved SFI. In conclusion, our novel STG method represents an easily reproducible and reliable model with close resemblance to the pathophysiological characteristics of SU model, and this can be easily reproduced by any lab.

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Flat Glass or Crystal Dome Aperture? A Year-Long Comparative Analysis of the Performance of Light Pipes in Real Residential Settings and Climatic Conditions

Sustainability ◽

10.3390/su12093858 ◽

2020 ◽

Vol 12 (9) ◽

pp. 3858 ◽

Cited By ~ 1

Author(s):

Magda Sibley ◽

Antonio Peña-García

Keyword(s):

Comparative Analysis ◽

Flat Glass ◽

Climatic Conditions ◽

Long Term Effect ◽

Different Types ◽

The Difference ◽

The Aesthetic ◽

One Year ◽

The One

This paper presents the first comparative study of its type of the performance of light pipes with different types of apertures: a flat glass versus a bohemian crystal dome. Measurements were taken at 20-minute intervals over a period of one year in the bathrooms of two newly built identical houses of the same orientation located in Manchester, UK. The comparative analysis of the data collected for both light pipes types reveals that the crystal domed aperture consistently outperforms the flat glass one. Furthermore, the difference in the recorded horizontal illuminance is most marked during the winter months and at the end of the one-year experiment, indicating that the crystal dome has better performance for low incident winter light and higher resistance for the long term effect of weathering and pollution. This study provides strong evidence based on long term real measurements. Such evidence informs architects’ decisions when weighing up the aesthetic considerations of a flat glass aperture versus the higher illumination levels afforded by a crystal dome aperture with higher resistance to weathering and pollution.

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