Corticostriatal deficits underlying cognitive impairments induced by fetal exposure to alcohol

The term Fetal Alcohol Spectrum Disorder (FASD) includes a group of diseases caused by fetal exposure to alcohol (FAE). FASD patients display heterogenous socio-emotional and cognitive deficits, particularly in the domain of executive function, which share symptoms with other neuropsychiatric disorders. Despite the availability of several preclinical models, the developmental brain defects causally linked to behavioral deficits induced by FAE remain poorly understood. Here, we first review the FAE-induced synaptic and circuit impairments in mesocorticolimbic areas involved in social and motor behaviors. Then, we consider the effects of FAE on cortical excitation/inhibition balance and its impact on both corticostriatal pathway function and cognitive abilities. In particular, we propose three non-mutually exclusive circuit models of corticostriatal dysfunctions to account for some of the FAE-induced cognitive deficits. One model posits that associative-sensorimotor imbalance causes hyper goal-directed behavior and a second model implies that alteration of prefrontal-striatal behavioral suppression circuits results in the loss of behavioral inhibition. A third model suggests that local striatal circuit deficits affect striatal neuronal ensemble function to impair action selection and performance. Finally, we discuss how pre-clinical approaches suggest potential rescue strategies for neuronal circuit defects in FASD patients.

Case Study on Abnormal Electron-Optical Frequency Mapping Phenomena in Failure Analysis

In recent years, laser reflectance modulation measurements are widely used in failure analysis. Among them, EOFM (Electron-Optical Frequency Mapping) technique is easy to operate and very practical. In this article, some images with abnormal EOFM phenomena and their corresponding defects are showing up, the causes of those abnormal EOFM phenomena are also pointed out. They prove that EOFM function is very effective for discovering open or high-impedance defects on metal trace and pinpointing short-circuit defects. In addition to the two aspects above, there are also some abnormal EOFM phenomena we couldn’t explain perfectly. We studied one of them and proposed two possible causes of the anomaly. After simulation experiment and calculation, it could be basically determined that the abnormal EOFM phenomenon was caused by the substrate noise current.

On the evaluation of a general model for optimum revolute cylindrical cylindrical cylindrical path generation

A general optimization model for the dimensional synthesis of defect free revolute cylindrical cylindrical cylindrical (RCCC) joint path generators is formulated, implemented and evaluated in this work. With this optimization model, RCCC dimensions required to approximate precision points are calculated. The model includes constraints to eliminate order, branch and circuit defects, which are common in dyad-based dimensional synthesis. Therefore, the originality of this work is the development of a general optimization model for RCCC path generation that simultaneously considers order, branch, and circuit defect elimination. This work demonstrates both the benefits and drawbacks realized when implementing the optimization model on a personal computer using the commercial mathematical analysis software package Matlab.

Revolute-Cylindrical-Cylindrical-Cylindrical linkage optimum dimensional synthesis with static structural loading

General optimization models for the dimensional synthesis of defect-free Revolute-Cylindrical-Cylindrical-Cylindrical linkages with static loading are formulated and evaluated in this work. With these optimization models, Revolute-Cylindrical-Cylindrical-Cylindrical linkage dimensions required to approximate coupler positions or coupler path points while achieving static equilibrium (given coupler loads) within a maximum driver static torque are calculated. These models also include constraints that eliminate order, branch and circuit defects-defects that are common in traditional dyad-based dimensional synthesis. Therefore, the novelty of this work is the development of optimization models that permit the synthesis of order, branch and circuit defect-free Revolute-Cylindrical-Cylindrical-Cylindrical motion and path generators that also achieve static equilibrium within a maximum specified driver torque magnitude for specified coupler loads. This work conveys both the benefits and drawbacks realized when implementing these optimization models on a personal computer using the commercial mathematical analysis software package Matlab.