5 research outputs found
The ubiquitin proteasome system in glia and its role in neurodegenerative diseases
The ubiquitin proteasome system (UPS) is crucial for intracellular protein homeostasis and for degradation of aberrant and damaged proteins. The accumulation of ubiquitinated proteins is a hallmark of many neurodegenerative diseases, including amyotrophic lateral sclerosis, Alzheimer's, Parkinson's, and Huntington's disease, leading to the hypothesis that proteasomal impairment is contributing to these diseases. So far, most research related to the UPS in neurodegenerative diseases has been focused on neurons, while glial cells have been largely disregarded in this respect. However, glial cells are essential for proper neuronal function and adopt a reactive phenotype in neurodegenerative diseases, thereby contributing to an inflammatory response. This process is called reactive gliosis, which in turn affects UPS function in glial cells. In many neurodegenerative diseases, mostly neurons show accumulation and aggregation of ubiquitinated proteins, suggesting that glial cells may be better equipped to maintain proper protein homeostasis. During an inflammatory reaction, the immunoproteasome is induced in glia, which may contribute to a more efficient degradation of disease-related proteins. Here we review the role of the UPS in glial cells in various neurodegenerative diseases, and we discuss how studying glial cell function might provide essential information in unraveling mechanisms of neurodegenerative diseases
User Context Aware Base Station Power Flow Model
At present the testing of power amplifiers within
base station transmitters is limited to testing at component level as
opposed to testing at the system level. While the detection of
catastrophic failure is possible, that of performance degradation is
not. This paper proposes a base station model with respect to
transmitter output power with the aim of introducing system level
monitoring of the power amplifier behaviour within the base
station. Our model reflects the expected output levels of second or
third generation CDMA base stations conforming to the Open Base
Station Architecture Initiative (OBSAI) open base station reference
architecture. The simulated base station output power is verified by
comparison to field data using such metrics as power
complementary cumulative distribution function (CCDF), volatility,
absolute deviation, mean absolute deviation and rate of change