Impact of open surface area of multi-well microelectrode array on mammalian brain cells recording efficiency

2020 ◽  
Author(s):  
Roofia (Sara) Pishgar ◽  
Pierre Wijdenes ◽  
Fahad Iqbal ◽  
Kazim Haider ◽  
Atika Syeda ◽  
...  
Keyword(s):  
Surface Area ◽  
Microelectrode Array ◽  
Mammalian Brain ◽  
Brain Cells ◽  
Open Surface ◽  
Recording Efficiency

Application of compact silencers as a noise barrier to a naturally ventilated double-skin façade

2021 ◽  
Vol 69 (3) ◽  
pp. 220-228
Author(s):  
Jeehwan Lee ◽  
Jae D. Chang ◽  
Robert Coffeen
Keyword(s):  
Noise Reduction ◽  
Surface Area ◽  
Natural Ventilation ◽  
Experimental Investigations ◽  
Test Case ◽  
Open Surface ◽  
Low Frequencies ◽  
Noise Barrier ◽  
Double Skin ◽  
Air Vent

A prior study of the acoustical performance of a double-skin facade (DSF) as a noise barrier was carried out based on the percentage of the air vent open surface area, shading louver configurations, and shading louver surface materials. Earlier research findings led to experimental investigations of the acoustical performance capabilities of compact silencers to replace DSF air vents as both noise barriers and air channels because DSF air cavities, which contribute to natural ventilation performance (e.g., wind-driven or buoyancy-driven performance), are acoustically vulnerable to noise transmitted through the air vents. This experimental investigation aims to explore noise reduction (NR) through compact silencers applied to DSF air vents. Double-skin facade mock-up test cases were designed based on three test scenarios of a ventilation open surface area: (1) a 100%air vent open surface area (open mode), (2) a 0% air vent open surface area (closed mode), and (3) a compact silencer. From a data analysis of DSF mock-up test results, the overall NR values of a DSFmock-up ranged from20 to 37 dB(A) depending on the number of compact silencers and the shading louver orientation used. Configurations of compact silencers and shading louvers helped the DSF mock-up achieve additionalNR values of 5 to 10 dB(A) depending on the test case. Moreover, applying compact silencers to a naturally ventilated DSF mock-up led to significant noise reduction at low frequencies (125Hz).

scholarly journals The Chemically Synthesized Ageladine A-Derivative LysoGlow84 Stains Lysosomes in Viable Mammalian Brain Cells and Specific Structures in the Marine Flatworm Macrostomum lignano

Marine Drugs ◽  
2015 ◽  
Vol 13 (2) ◽  
pp. 920-935 ◽  
Author(s):  
Thorsten Mordhorst ◽  
Sushil Awal ◽  
Sebastian Jordan ◽  
Charlotte Petters ◽  
Linda Sartoris ◽  
...  
Keyword(s):  
Mammalian Brain ◽  
Brain Cells ◽  
Macrostomum Lignano

scholarly journals Deuterated Glutamate-Mediated Neuronal Activity on Micro-Electrode Arrays

Micromachines ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 830
Author(s):  
Wataru Minoshima ◽  
Kyoko Masui ◽  
Tomomi Tani ◽  
Yasunori Nawa ◽  
Satoshi Fujita ◽  
...  
Keyword(s):  
Spontaneous Activity ◽  
Neuronal Activity ◽  
Hippocampal Neurons ◽  
Neuronal Networks ◽  
Microelectrode Array ◽  
Mammalian Brain ◽  
Electrode Arrays ◽  
Physiological Properties ◽  
Micro Electrode Arrays

The excitatory synaptic transmission is mediated by glutamate (GLU) in neuronal networks of the mammalian brain. In addition to the synaptic GLU, extra-synaptic GLU is known to modulate the neuronal activity. In neuronal networks, GLU uptake is an important role of neurons and glial cells for lowering the concentration of extracellular GLU and to avoid the excitotoxicity. Monitoring the spatial distribution of intracellular GLU is important to study the uptake of GLU, but the approach has been hampered by the absence of appropriate GLU analogs that report the localization of GLU. Deuterium-labeled glutamate (GLU-D) is a promising tracer for monitoring the intracellular concentration of glutamate, but physiological properties of GLU-D have not been studied. Here we study the effects of extracellular GLU-D for the neuronal activity by using primary cultured rat hippocampal neurons that form neuronal networks on microelectrode array. The frequency of firing in the spontaneous activity of neurons increased with the increasing concentration of extracellular GLU-D. The frequency of synchronized burst activity in neurons increased similarly as we observed in the spontaneous activity. These changes of the neuronal activity with extracellular GLU-D were suppressed by antagonists of glutamate receptors. These results suggest that GLU-D can be used as an analog of GLU with equivalent effects for facilitating the neuronal activity. We anticipate GLU-D developing as a promising analog of GLU for studying the dynamics of glutamate during neuronal activity.

scholarly journals Mitotic defects lead to neuronal aneuploidy and apoptosis in frontotemporal lobar degeneration caused by MAPT mutations

2018 ◽  
Vol 29 (5) ◽  
pp. 575-586 ◽  
Author(s):  
Julbert Caneus ◽  
Antoneta Granic ◽  
Rosa Rademakers ◽  
Dennis W. Dickson ◽  
Christina M. Coughlan ◽  
...  
Keyword(s):  
Mitotic Spindle ◽  
Frontotemporal Lobar Degeneration ◽  
Gene Dosage ◽  
Human Lymphocytes ◽  
Chromosome Instability ◽  
Mammalian Brain ◽  
Brain Cells ◽  
Brain Neurons ◽  
Normal Human ◽  
Mutant Forms

Mutant Tau (MAPT) can lead to frontotemporal lobar degeneration (FTLD). Previous studies associated MAPT mutations and altered function with aneuploidy and chromosome instability in human lymphocytes and in Drosophila development. Here we examine whether FTLD-causing mutations in human MAPT induce aneuploidy and apoptosis in the mammalian brain. First, aneuploidy was found in brain cells from MAPT mutant transgenic mice expressing FTLD mutant human MAPT. Then brain neurons from mice homozygous or heterozygous for the Tau (Mapt) null allele were found to exhibit increasing levels of aneuploidy with decreasing Tau gene dosage. To determine whether aneuploidy leads to neurodegeneration in FTLD, we measured aneuploidy and apoptosis in brain cells from patients with MAPT mutations and identified both increased aneuploidy and apoptosis in the same brain neurons and glia. To determine whether there is a direct relationship between MAPT-induced aneuploidy and apoptosis, we expressed FTLD-causing mutant forms of MAPT in karyotypically normal human cells and found that they cause aneuploidy and mitotic spindle defects that then result in apoptosis. Collectively, our findings reveal a neurodegenerative pathway in FTLD-MAPT in which neurons and glia exhibit mitotic spindle abnormalities, chromosome mis-segregation, and aneuploidy, which then lead to apoptosis.

The differential distribution of beta tubulin mRNAs in individual mammalian brain cells

1985 ◽  
Vol 27 (3) ◽  
pp. 205-214 ◽  
Author(s):  
W. Sue T. Griffin ◽  
Michael A. Alejos ◽  
Erica J. Cox ◽  
Marcelle R. Morrison
Keyword(s):  
Mammalian Brain ◽  
Brain Cells ◽  
Differential Distribution ◽  
Beta Tubulin

Thermal Performance Analysis of a Partly Closed-Open Solar Regenerator

1995 ◽  
Vol 117 (2) ◽  
pp. 151-153 ◽  
Author(s):  
P. Gandhidasan ◽  
A. A. Al-Farayedhi
Keyword(s):  
Performance Analysis ◽  
Surface Area ◽  
Thermal Performance ◽  
Operating Parameters ◽  
Open Surface ◽  
Regeneration System ◽  
Liquid Desiccant ◽  
Regeneration Efficiency

This paper presents a modified open regeneration system suitable for humid climates. The upper part of the open regenerator is covered with a single glazing where the desiccant can be heated up without evaporation of water and the evaporation starts at the beginning of the open surface. For this type of regenerator, performance analysis has been made to predict the mass of water evaporated from the weak liquid desiccant to the atmosphere. The regeneration efficiency is obtained for various ratios of glaze surface area to the open surface area for different operating parameters.

scholarly journals Improved distribution of small molecules and viral vectors in the murine brain using a hollow fiber catheter

2007 ◽  
Vol 107 (3) ◽  
pp. 568-577 ◽  
Author(s):  
Seunguk OH ◽  
Rick Odland ◽  
Scott R. Wilson ◽  
Kurt M. Kroeger ◽  
Chunyan Liu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Therapy ◽  
Gene Transfer ◽  
Surface Area ◽  
Brain Tissue ◽  
Mouse Brain ◽  
Hollow Fiber ◽  
Luciferase Reporter ◽  
Mammalian Brain

Object A hollow fiber catheter was developed to improve the distribution of drugs administered via direct infusion into the central nervous system (CNS). It is a porous catheter that significantly increases the surface area of brain tissue into which a drug is infused. Methods Dye was infused into the mouse brain through convection-enhanced delivery (CED) using a 28-gauge needle compared with a 3-mm-long hollow fiber catheter. To determine whether a hollow fiber catheter could increase the distribution of gene therapy vectors, a recombinant adenovirus expressing the firefly luciferase reporter was injected into the mouse striatum. Gene expression was monitored using in vivo bioluminescent imaging. To assess the distribution of gene transfer, an adenovirus expressing green fluorescent protein was injected into the striatum using a hollow fiber catheter or a needle. Results Hollow fiber catheter–mediated infusion increased the volume of brain tissue labeled with dye by 2.7 times relative to needle-mediated infusion. In vivo imaging revealed that catheter-mediated infusion of adenovirus resulted in gene expression that was 10 times greater than that mediated by a needle. The catheter appreciably increased the area of brain transduced with adenovirus relative to a needle, affecting a significant portion of the injected hemisphere. Conclusions The miniature hollow fiber catheter used in this study significantly increased the distribution of dye and adenoviral-mediated gene transfer in the mouse brain compared with the levels reached using a 28-gauge needle. Compared with standard single-port clinical catheters, the hollow fiber catheter has the advantage of millions of nanoscale pores to increase surface area and bulk flow in the CNS. Extending the scale of the hollow fiber catheter for the large mammalian brain shows promise in increasing the distribution and efficacy of gene therapy and drug therapy using CED.

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