Publications by authors named "Scott D Adams"

10 Publications

  • Page 1 of 1

An FSCV Deep Neural Network: Development, Pruning, and Acceleration on an FPGA.

IEEE J Biomed Health Inform 2021 Jun 3;25(6):2248-2259. Epub 2021 Jun 3.

Fast-scan cyclic voltammetry (FSCV) is an electrochemical technique for measuring rapid changes in the extracellular concentration of neurotransmitters within the brain. Due to its fast scan rate and large output-data size, the current analysis of the FSCV data is often conducted on a computer external to the FSCV device. Moreover, the analysis is semi-automated and requires a good understanding of the characteristics of the underlying chemistry to interpret, making it unsuitable for real-time implementation on low-resource FSCV devices. This paper presents a hardware-software co-design approach for the analysis of FSCV data. Firstly, a deep neural network (DNN) is developed to predict the concentration of a dopamine solution and identify the data recording electrode. Secondly, the DNN is pruned to decrease its computation complexity, and a custom overlay is developed to implement the pruned DNN on a low-resource FPGA-based platform. The pruned DNN attains a recognition accuracy of 97.2% with a compression ratio of 3.18. When the DNN overlay is implemented on a PYNQ-Z2 platform, it achieves the execution time of 13 ms and power consumption of 1.479 W on the entire PYNQ-Z2 board. This study demonstrates the possibility of operating the DNN for FSCV data analysis on portable FPGA-based platforms.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/JBHI.2020.3037366DOI Listing
June 2021

Miniature Resistance Measurement Device for Structural Health Monitoring of Reinforced Concrete Infrastructure.

Sensors (Basel) 2020 Aug 2;20(15). Epub 2020 Aug 2.

School of Engineering, Deakin University, Geelong, VIC 3216, Australia.

A vast amount of civil infrastructure is constructed using reinforced concrete, which can be susceptible to corrosion, posing significant risks. Corrosion of reinforced concrete has various causes, with chloride ingress known to be a major contributor. Monitoring this chloride ingress would allow for preventative maintenance to be less intrusive at a lower cost. Currently, chloride sensing methods are bulky and expensive, leaving the majority of concrete infrastructures unmonitored. This paper presents the design and fabrication of a miniature, low-cost device that can be embedded into concrete at various locations and depths. The device measures localized concrete resistance, correlating to the chloride ingress in the concrete using equations listed in this paper, and calculated results from two experiments are presented. The device benefits from a four-probe architecture, injecting a fixed frequency AC waveform across its outer electrodes within the cement block. Voltage across the internal electrodes is measured with a microcontroller and converted to a resistance value, communicated serially to an external computer. A final test showcases the ability of the device for three-dimensional mass deployment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/s20154313DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7435588PMC
August 2020

TinyFSCV: FSCV for the Masses.

IEEE Trans Neural Syst Rehabil Eng 2020 01 28;28(1):133-142. Epub 2019 Nov 28.

The ability to monitor neurochemical dynamics in target brain regions with a high degree of temporal resolution has assisted researchers in investigating the pathogenesis, and pathophysiology of a variety of neurological and psychiatric disorders. Current systems for neurochemical monitoring are bulky or expensive, limiting widespread exploration of this research field and preventing large-scale parallel experimentation. In this paper, we present a new miniaturized research platform, the TinyFSCV system, which can be used to monitor dynamic changes in neurochemicals through Fast-Scan Cyclic Voltammetry (FSCV). This system contains a precision voltage output circuit that can accurately output potentials between -0.55 to 2 V and scan a connected electrochemical cell at up to 400 V/s, the required speed to sense most neurochemicals with FSCV. In addition, the device includes precision current measurement circuity with a measurement range of -115 to [Formula: see text] capable of taking measurements at up to 56 KS/s. Four experiments are conducted to demonstrate the capability of the system. These consisted of: static bench tests, static ferrocene tests, and static and dynamic dopamine tests. These experiments demonstrate the ability of the miniaturized platform to accurately sense and measure neurochemicals. Ultimately, the TinyFSCV system is a platform that can enable large-scale, low-cost parallel experimentation to take place in the field of neurochemical monitoring. In addition, this device will increase the accessibility of neurochemical sensing, providing advanced tools and techniques to more researchers, and facilitating widespread exploration of the field of neurodynamics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1109/TNSRE.2019.2956479DOI Listing
January 2020

Development of a miniature device for emerging deep brain stimulation paradigms.

PLoS One 2019 21;14(2):e0212554. Epub 2019 Feb 21.

Deakin University, School of Engineering, Geelong, Victoria, Australia.

Deep brain stimulation (DBS) is a neuromodulatory approach for treatment of several neurological and psychiatric disorders. A new focus on optimising the waveforms used for stimulation is emerging regarding the mechanism of DBS treatment. Many existing DBS devices offer only a limited set of predefined waveforms, mainly rectangular, and hence are inapt for exploring the emerging paradigm. Advances in clinical DBS are moving towards incorporating new stimulation parameters, yet we remain limited in our capacity to test these in animal models, arguably a critical first step. Accordingly, there is a need for the development of new miniature, low-power devices to enable investigation into the new DBS paradigms in preclinical settings. The ideal device would allow for flexibility in the stimulation waveforms, while remaining suitable for chronic, tetherless, biphasic deep brain stimulation. In this work, we elucidate several key parameters in a DBS system, identify gaps in existing solutions, and propose a new device to support preclinical DBS. The device allows for a high degree of flexibility in the output waveform with easily altered shape, frequency, pulse-width and amplitude. The device is suitable for both traditional and modern stimulation schemes, including those using non-rectangular waveforms, as well as delayed feedback schemes. The device incorporates active charge balancing to ensure safe operation, and allows for simple production of custom biphasic waveforms. This custom waveform output is unique in the field of preclinical DBS devices, and could be advantageous in performing future DBS studies investigating new treatment paradigms. This tetherless device can be easily and comfortably carried by an animal in a back-mountable configuration. The results of in-vitro tests are presented and discussed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0212554PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6383994PMC
November 2019

Surface nanogrooving of carbon microtubes.

Sci Rep 2018 Jul 2;8(1):9924. Epub 2018 Jul 2.

School of Engineering, Deakin University, Geelong, Victoria, 3216, Australia.

Extrusion processing of carbon tubes can be problematic due to their poor interfacial interactions with polymeric matrices. Surface chemical modification of carbon tubes can be utilized to create bonding sites to form networks with polymer chains. However, chemical reactions resulting in intermolecular primary bonding limit processability of extrudate, since they cause unstable rheological behaviour, and thus decrease the stock holding time, which is determinative in extrusion. This study presents a method for the synthesis of carbon microtubes with physically modified surface area to improve the filler and matrix interfacial interactions. The key concept is the formation of a nanogrooved topography, through acoustic cavitation on the surface of processing fibres. The effect of nanogrooving on roughness parameters is described, along with the role of surface modified carbon tubes on rheological behaviour, homogeneity, and coherency of extrudate. The measurements showed that nanogrooving increases the surface area of carbon microtubes, as a result, die swelling of the extrudate is reduced. Furthermore, after solidification, the mechanical strength of composite is reinforced due to stronger interactions between nanogrooved carbon tubes and polymer matrix.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-018-28313-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6028628PMC
July 2018

An investigation into closed-loop treatment of neurological disorders based on sensing mitochondrial dysfunction.

J Neuroeng Rehabil 2018 02 13;15(1). Epub 2018 Feb 13.

School of Medicine, Deakin University, Waurn Ponds, VIC, 3216, Australia.

Dynamic feedback based closed-loop medical devices offer a number of advantages for treatment of heterogeneous neurological conditions. Closed-loop devices integrate a level of neurobiological feedback, which allows for real-time adjustments to be made with the overarching aim of improving treatment efficacy and minimizing risks for adverse events. One target which has not been extensively explored as a potential feedback component in closed-loop therapies is mitochondrial function. Several neurodegenerative and psychiatric disorders including Parkinson's disease, Major Depressive disorder and Bipolar disorder have been linked to perturbations in the mitochondrial respiratory chain. This paper investigates the potential to monitor this mitochondrial function as a method of feedback for closed-loop neuromodulation treatments. A generic model of the closed-loop treatment is developed to describe the high-level functions of any system designed to control neural function based on mitochondrial response to stimulation, simplifying comparison and future meta-analysis. This model has four key functional components including: a sensor, signal manipulator, controller and effector. Each of these components are described and several potential technologies for each are investigated. While some of these candidate technologies are quite mature, there are still technological gaps remaining. The field of closed-loop medical devices is rapidly evolving, and whilst there is a lot of interest in this area, widespread adoption has not yet been achieved due to several remaining technological hurdles. However, the significant therapeutic benefits offered by this technology mean that this will be an active area for research for years to come.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12984-018-0349-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5811973PMC
February 2018

Nucleotide pyrophosphatase employs a P-loop-like motif to enhance catalytic power and NDP/NTP discrimination.

Proc Natl Acad Sci U S A 2011 Aug 10;108(35):14437-42. Epub 2011 Aug 10.

Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, H-1113, Budapest, Karolina út 29., Hungary.

We investigated the potential (d)NDP/(d)NTP discrimination mechanisms in nucleotide pyrophosphatases. Here, we report that dUTPase, an essential nucleotide pyrophosphatase, uses a C-terminal P-loop-like sequence in a unique mechanism for substrate discrimination and efficient hydrolysis. Our spectroscopy and transient kinetics results on human dUTPase mutants combined with previous structural studies indicate that (i) H-bond interactions between the γ-phosphate and the P-loop-like motif V promote the catalytically competent conformation of the reaction center at the α-phosphate group; (ii) these interactions accelerate the chemical step of the kinetic cycle and that (iii) hydrolysis occurs very slowly or not at all in the absence of the γ-phosphate--motif V interactions, i.e., in dUDP, dUDP.BeFx, or in the motif V-deleted mutant. The physiological role of dUTPase is to set cellular dUTPdTTP ratios and prevent injurious uracil incorporation into DNA. Based upon comparison with related pyrophosphate generating (d)NTPases, we propose that the unusual use of a P-loop-like motif enables dUTPases to achieve efficient catalysis of dUTP hydrolysis and efficient discrimination against dUDP at the same time. These specifics might have been advantageous on the appearance of uracil-DNA repair. The similarities and differences between dUTPase motif V and the P-loop (or Walker A sequence) commonly featured by ATP- and GTPases offer insight into functional adaptation to various nucleotide hydrolysis tasks.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1013872108DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3167503PMC
August 2011

Social Cognition and Interaction Training (SCIT) for inpatients with schizophrenia spectrum disorders: preliminary findings.

Schizophr Res 2007 Mar 12;91(1-3):112-6. Epub 2007 Feb 12.

University of Tulsa, Department of Psychology, 600 South College Ave. Tulsa, OK 74104, USA.

Individuals with schizophrenia exhibit consistent deficits in social cognition such as emotion perception, attributional style, and theory of mind, which may be targets of psychosocial treatments. Previous intervention studies have typically focused on only one aspect of social cognition and have not assessed generalization of treatment to improvements in social functioning. This paper describes preliminary data from a new group-based treatment, Social Cognition and Interaction Training (SCIT), aimed at improving social cognition in schizophrenia. Eighteen inpatients with schizophrenia spectrum disorders completed SCIT and were compared with 10 inpatients who completed a coping skills group. Participants were assessed at pre-test and post-test on measures of emotion and social perception, theory of mind, attributional style (e.g., blame, hostility, and aggression), cognitive flexibility, and social relationships. We also collected data on the frequency of aggressive incidents on the treatment ward. The results showed that compared to the control group, SCIT participants improved on all of the social cognitive measures and showed better self-reported social relationships and fewer aggressive incidents on the treatment unit at post-test. Importantly, this change was independent of changes in clinical symptoms over time and supports the unique role of SCIT in improving social cognitive deficits in schizophrenia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.schres.2006.12.010DOI Listing
March 2007

The conviction of delusional beliefs scale: reliability and validity.

Schizophr Res 2006 Sep 1;86(1-3):80-8. Epub 2006 Aug 1.

University of Tulsa, Department of Psychology, Lorton Hall, Tulsa, OK 74104, USA.

This study reports on the development of a new measure of delusional belief conviction, the Conviction of Delusional Beliefs Scale (CDBS). Most of the current scales in use assess belief conviction with a single item and primarily reflect the cognitive aspects of conviction. The CDBS represents an improvement over existing scales in that it contains a larger number of test items that can be subjected to psychometric examination. In addition, the CDBS also broadens the concept of belief conviction by incorporating cognitive, emotional, and behavioral items. In the present study, fifty participants with delusions completed the CDBS along with measures of delusional ideation, psychiatric symptomatology, insight, and reading ability. The CDBS showed very good levels of internal consistency and test-retest stability over a six-week period. All of the CDBS items loaded highly on a unitary factor of belief conviction. The CDBS positively correlated with four measures of belief conviction thereby reflecting the convergent validity of the scale. The CDBS was unrelated to other dimensions of delusional ideation, psychiatric symptomatology, insight, and reading ability, which supported the discriminant validity of the scale. The CDBS appears to be a reliable and valid measure of delusional belief conviction that could be used in clinical and research settings.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.schres.2006.06.023DOI Listing
September 2006

Informed consent in schizophrenia: the use of cues in the assessment of understanding.

Schizophr Res 2005 Sep;77(1):59-63

Department of Psychology, University of Tulsa, Lorton Hall, Room 308, 600 South College Ave., Tulsa, OK 74104, United States.

The purpose of this study was to determine if providing cues could facilitate participant understanding for consent form information. Understanding scores were measured in a group of participants diagnosed with schizophrenia and a control group using cued recognition and uncued recall methods. When understanding was measured with uncued methods, persons with schizophrenia showed lower scores compared to the control group. However, when cues were provided, there was no difference between the two groups on understanding scores, and persons with schizophrenia showed normal levels of understanding. The results suggest that cued methods may be a better alternative to measure participant understanding.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.schres.2004.08.002DOI Listing
September 2005