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  1. Free, publicly-accessible full text available August 1, 2024
  2. Hydrogen-bonded frameworks (HBFs) have been studied for decades owing to their fascinating and diverse architectures, always with an eye toward the role of hydrogen bonding in their design as well as their utility in various applications. This review addresses recent advances in HBFs that illustrate their versatility and utility stemming from their unique attributes compared with other classes of molecular frameworks. Guanidinium organosulfonate hydrogen-bonded frameworks, pioneered in our lab and one of the most extensive and versatile collections of HBFs, are used to illustrate molecular design concepts and the principle of architectural isomerism that expands access to a greater structural landscape. Recognizing the growing role of computation in materials design, from ab initio methods to machine learning, this review also touches on their emerging use in the design and synthesis of HBFs. The growth of the HBF arsenal promises continuing innovations, with applications ranging from electronic materials and chemical separations to gas adsorption and catalysis. 
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  3. Abstract

    The mechanism of action of deep brain stimulation (DBS) to the basal ganglia for Parkinson’s disease remains unclear. Studies have shown that DBS decreases pathological beta hypersynchrony between the basal ganglia and motor cortex. However, little is known about DBS’s effects on long range corticocortical synchronization. Here, we use machine learning combined with graph theory to compare resting-state cortical connectivity between the off and on-stimulation states and to healthy controls. We found that turning DBS on increased high beta and gamma band synchrony (26 to 50 Hz) in a cortical circuit spanning the motor, occipitoparietal, middle temporal, and prefrontal cortices. The synchrony in this network was greater in DBS on relative to both DBS off and controls, with no significant difference between DBS off and controls. Turning DBS on also increased network efficiency and strength and subnetwork modularity relative to both DBS off and controls in the beta and gamma band. Thus, unlike DBS’s subcortical normalization of pathological basal ganglia activity, it introduces greater synchrony relative to healthy controls in cortical circuitry that includes both motor and non-motor systems. This increased high beta/gamma synchronization may reflect compensatory mechanisms related to DBS’s clinical benefits, as well as undesirable non-motor side effects.

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