scholarly journals Multichannel Silicon Probes for Awake Hippocampal Recordings in Large Animals

2018 ◽  
Author(s):  
Alexandra V. Ulyanova ◽  
Carlo Cottone ◽  
Christopher D. Adam ◽  
Kimberly G. Gagnon ◽  
D. Kacy Cullen ◽  
...  
Keyword(s):  
Single Unit ◽  
Brain Structures ◽  
Neural Interface ◽  
Large Animal ◽  
Cross Sectional ◽  
Large Animal Models ◽  
Cortical Regions ◽  
Over Time ◽  
Deep Brain ◽  
Silicon Probes

AbstractDecoding laminar information across deep brain structures and cortical regions is necessary in order to understand the spatiotemporal ensembles that represent cognition and memory. Large animal models are essential for translational research due to their gyrencephalic neuroanatomy and significant white matter composition. One of the major obstacles to applying the approaches currently utilized in lower order animals are technical limitations in silicon probes, specifically a lack of long-length probes with appropriate stiffness to penetrate to deeper structures with minimal damage to the neural interface. We tested various solutions and designs of multichannel silicon probes developed for large animal electrophysiology by recording neurophysiological signals from deep laminar structures in an acute preparation and in chronically implanted awake behaving Yucatan pigs. Electrophysiological parameters of single units and local field potentials were analyzed to evaluate performance over time of given silicon probes in chronic implantations. The cross-sectional area of silicon probes was found to be a crucial determinant of silicon probes’ single unit performance over time, potentially due to reduction of damage to the neural interface. EDGE-style probes had the highest yields during intra-hippocampal recordings in pigs, making them the most suitable for chronic implantations and awake behavioral experimentation. Novel CAMB 64-channel EDGE-style probes with linear and poly-2 site arrangement tested acutely had optimal single unit separation and a denser sampling of the laminar structure, identifying them as potential candidates for chronic implantations with less cortical damage above the active portion of the probe. This study provides an analysis of multichannel silicon probes designed for large animal laminar electrophysiology of deep brain structures, and suggests that current designs are reaching the physical thresholds necessary for long-term (~ 1 month) recordings from laminar deep structures with single-unit resolution.

scholarly journals Electrophysiological Signature Reveals Laminar Structure of the Porcine Hippocampus

2017 ◽  
Author(s):  
Alexandra V. Ulyanova ◽  
Paul F. Koch ◽  
Carlo Cottone ◽  
Michael R. Grovola ◽  
Christopher D. Adam ◽  
...  
Keyword(s):  
Episodic Memory ◽  
Single Unit ◽  
Dorsal Hippocampus ◽  
Region Of Interest ◽  
Large Animal ◽  
Field Potentials ◽  
Laminar Structure ◽  
Large Animal Models ◽  
Silicon Probes

AbstractThe hippocampus is integral to working and episodic memory, and is a central region of interest in diseases affecting these processes. Pig models are widely used in translational research, and may provide an excellent bridge between rodents and non-human primates for CNS disease models due to their gyrencephalic neuroanatomy and significant white matter composition. However, the laminar structure of the pig hippocampus has not been well characterized. Therefore, we histologically characterized the dorsal hippocampus of Yucatan miniature pigs and quantified the cytoarchitecture of the hippocampal layers. We then utilized stereotaxis combined with single unit electrophysiological mapping to precisely place multichannel laminar silicon probes into the dorsal hippocampus without the need for image guidance. We usedin vivoelectrophysiological recordings of simultaneous laminar field potentials and single unit activity in multiple layers of the dorsal hippocampus to physiologically identify and quantify these layers under anesthesia. Consistent with previous reports, we found the porcine hippocampus to have the expected archicortical laminar structure with some anatomical and histological features comparable to the rodent and others to the primate hippocampus. Importantly, we found these distinct features to be reflected in the laminar electrophysiology. This characterization, as well as our electrophysiology-based methodology targeting the porcine hippocampal lamina combined with high channel count silicon probes will allow for analysis of spike-field interactions during normal and disease states in both anesthetized and future awake behaving neurophysiology in this large animal.Significance StatementThe hippocampus is central to working and episodic memory and is critically affected by diverse disease processes. In order to investigate hippocampal electrophysiology in translational large animal models, we developed an imaging-free stereotaxis and intraoperative electrophysiology methodology with custom silicon probes to precisely localize probe placement within the hippocampal laminar structure. We report for the first time the profile of single units and local field potentials in the pig dorsal hippocampus and relate them to a histological description. This characterization forms the basis for accessible translational pig models to study diseases of the central nervous system affecting hippocampal circuitry in the large animal gyrencephalic brain, as well as the groundwork for potential awake behaving neurophysiology of the porcine hippocampus.Funding SourcesThe Department of Veterans Affairs, IK2-RX001479, I01-RX001097. The National Institutes of Health, NINDS R01-NS-101108-01, T32-NS043126. CURE Foundation, Taking Flight Award. DoD ERP CDMRP, W81XWH-16-1-0675.

scholarly journals Pressure-Regulated Ventilator Splitting (PReVentS) – A COVID-19 Response Paradigm from Yale University

2020 ◽  
Author(s):  
Micha Sam Brickman Raredon ◽  
Clark Fisher ◽  
Paul Heerdt ◽  
Ranjit Deshpande ◽  
Steven Nivison ◽  
...  
Keyword(s):  
Gas Flow ◽  
Pressure Control ◽  
Lung Compliance ◽  
Large Animal ◽  
Yale University ◽  
Care Community ◽  
Large Animal Models ◽  
Fda Approval ◽  
The Us ◽  
Over Time

AbstractIn the current COVID-19 crisis, the US and many countries in the world are suffering acute shortages of modern ventilators to care for desperately ill patients. Since modern ICU ventilators are powerful devices that can deliver very high gas flow rates and pressures, multiple physicians have attempted to ventilate more than one patient on a single ventilator – so-called “vent splitting”. Early applications of this approach have utilized simple concatenations of ventilator tubing and T-pieces, to provide flow to more than one patient. Additional approaches using custom flow splitters – sometimes made using 3D printing technologies – have also advanced into the clinic with FDA approval. However, heretofore there has been less progress made on controlling individual ventilatory pressures for patients with severe lung disease. Given the inherent variability and instability of lung compliance amongst patients with COVID-19, there remains an important need to provide a means of extending ventilator usefulness to more than one patient, but in a way that provides more tailored pressures that can be titrated over time. In this descriptive report, we provide the basis for a ventilator circuit that can support two patients with individualized peak inspiratory and end-expiratory pressures. The circuit is comprised of exclusively “off the shelf” materials and is inexpensive to produce. The circuit can be used with typical ICU ventilators, and with anesthesia ventilators used in operating rooms. Inspiratory and end-expiratory pressures for each patient can be titrated over time, without changes for one patient affecting the ventilation parameters of the other patient. Using in-line spirometry, individual tidal volumes can be measured for each patient. This Pressure-Regulated Ventilator Splitting (PReVentS) Yale University protocol operates under a pressure-control ventilatory mode, and may function optimally when patients are not triggering breaths from the ventilator.This method has been tested thus far only in the laboratory with mock lungs, and has not yet been deployed in animals or in patients. However, given the novelty and potential utility of this approach, we deemed it appropriate to provide this information to the broader critical care community at the present time. In coming days and weeks, we will continue to characterize and refine this approach, using large animal models and proof-of-principle human studies.

scholarly journals A multiwire microelectrode for single unit recording in deep brain structures

1990 ◽  
Vol 32 (2) ◽  
pp. 143-148 ◽  
Author(s):  
Dieter Jaeger ◽  
Sid Gilman ◽  
J. Wayne Aldridge
Keyword(s):  
Single Unit ◽  
Brain Structures ◽  
Single Unit Recording ◽  
Unit Recording ◽  
Deep Brain

The Path of Standard Albanian Language Formation

2018 ◽  
Vol 5 (2) ◽  
pp. 106-115
Author(s):  
Sindorela Doli Kryeziu
Keyword(s):  
Single Unit ◽  
Cultural Factors ◽  
Language History ◽  
Whole Process ◽  
History Of ◽  
Social And Cultural Factors ◽  
Cultural Body ◽  
Over Time ◽  
Language Literature

Abstract In our paper we will talk about the whole process of standardization of the Albanian language, where it has gone through a long historical route, for almost a century.When talking about standard Albanian language history and according to Albanian language literature, it is often thought that the Albanian language was standardized in the Albanian Language Orthography Congress, held in Tirana in 1972, or after the publication of the Orthographic Rules (which was a project at that time) of 1967 and the decisions of the Linguistic Conference, a conference of great importance that took place in Pristina, in 1968. All of these have influenced chronologically during a very difficult historical journey, until the standardization of the Albanian language.Considering a slightly wider and more complex view than what is often presented in Albanian language literature, we will try to describe the path (history) of the standard Albanian formation under the influence of many historical, political, social and cultural factors that are known in the history of the Albanian people. These factors have contributed to the formation of a common state, which would have, over time, a common standard language.It is fair to think that "all activity in the development of writing and the Albanian language, in the field of standardization and linguistic planning, should be seen as a single unit of Albanian culture, of course with frequent manifestations of specific polycentric organization, either because of divisions within the cultural body itself, or because of the external imposition"(Rexhep Ismajli," In Language and for Language ", Dukagjini, Peja, 1998, pp. 15-18.)

scholarly journals High-fidelity transmission of high-frequency burst stimuli from peripheral nerve to thalamic nuclei in children with dystonia

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Estefanía Hernandez-Martin ◽  
Enrique Arguelles ◽  
Yifei Zheng ◽  
Ruta Deshpande ◽  
Terence D. Sanger
Keyword(s):  
Deep Brain Stimulation ◽  
Peripheral Nerve ◽  
Brain Stimulation ◽  
High Frequency ◽  
Sensory Information ◽  
Brain Structures ◽  
High Fidelity ◽  
Thalamic Nuclei ◽  
Frequency Burst ◽  
Deep Brain

AbstractHigh-frequency peripheral nerve stimulation has emerged as a noninvasive alternative to thalamic deep brain stimulation for some patients with essential tremor. It is not known whether such techniques might be effective for movement disorders in children, nor is the mechanism and transmission of the peripheral stimuli to central brain structures understood. This study was designed to investigate the fidelity of transmission from peripheral nerves to thalamic nuclei in children with dystonia undergoing deep brain stimulation surgery. The ventralis intermediate (VIM) thalamus nuclei showed a robust evoked response to peripheral high-frequency burst stimulation, with a greatest response magnitude to intra-burst frequencies between 50 and 100 Hz, and reliable but smaller responses up to 170 Hz. The earliest response occurred at 12–15 ms following stimulation onset, suggesting rapid high-fidelity transmission between peripheral nerve and thalamic nuclei. A high-bandwidth, low-latency transmission path from peripheral nerve to VIM thalamus is consistent with the importance of rapid and accurate sensory information for the control of coordination and movement via the cerebello-thalamo-cortical pathway. Our results suggest the possibility of non-invasive modulation of thalamic activity in children with dystonia, and therefore the possibility that a subset of children could have beneficial clinical response without the need for invasive deep brain stimulation.

scholarly journals Changing landscape of nutrition and dietetics research? A bibliographic analysis of top-tier published research in 1998 and 2018

2021 ◽  
pp. 1-10
Author(s):  
Sze Lin Yoong ◽  
Jacklyn Jackson ◽  
Courtney Barnes ◽  
Nicole Pearson ◽  
Taren Swindle ◽  
...  
Keyword(s):  
Research Design ◽  
Dissemination And Implementation ◽  
Cross Sectional ◽  
Bibliographic Analysis ◽  
Type Design ◽  
Study Type ◽  
Nutrition And Dietetics ◽  
Published Research ◽  
Research Type ◽  
Over Time

Abstract Objective: The current study sought to describe and compare study type, research design and translation phase of published research in nutrition and dietetic journals in 1998 and 2018. Design: This was a repeat cross-sectional bibliographic analysis of Nutrition and Dietetics research. All eligible studies in the top eight Nutrition and Dietetics indexed journals in 1998 and 2018 were included. Two independent reviewers coded each study for research design (study type and study design) and translation phase (T0-T4) of the research using seminal texts in the field. Setting: Not relevant. Participants: Not relevant. Results: The number of publications (1998, n 1030; 2018, n 1016) has not changed over time, but the research type, design and translation phases have. The proportion of intervention studies in 1998 (43·8 %) was significantly higher than 2018 (19·4 %). In 2018, more reviews (46·9 % v. 15·6 % in 1998) and less randomised trials (14·3 % v. 37·8 % in 1998) were published. In regard to translation phase, there was a higher proportion of T2–T4 research in 2018 (18·3 % v. 3·8 % in 1998); however, the proportion of T3/T4 (dissemination, implementation and population-level research) research was still low (<3 %). Our sensitivity analysis with the four journals that remained in the top eight journal across the two time periods found no differences in the research type, design and translation phases across time. Conclusions: There was a reduction in intervention and T0 publications, alongside higher publication of clinical study designs over time; however, published T3/T4 research in Nutrition and Dietetics is low. A greater focus on publishing interventions and dissemination and implementation may be needed.

Are neighborhood restaurants related to frequency of restaurant meals and dietary quality?: Prevalence and changes over time in the Multi-Ethnic Study of Atherosclerosis

2021 ◽  
pp. 1-29
Author(s):  
Amy H. Auchincloss ◽  
Jingjing Li ◽  
Kari A. B. Moore ◽  
Manuel Franco ◽  
Mahasin S. Mujahid ◽  
...  
Keyword(s):  
Healthy Eating Index ◽  
Dietary Quality ◽  
Longitudinal Analyses ◽  
Cross Sectional ◽  
Cross Sectional Analysis ◽  
Eating Out ◽  
Restaurant Meals ◽  
Sectional Analysis ◽  
Over Time

Abstract Objective: To examine whether the density of neighbourhood restaurants affected the frequency of eating restaurant meals and subsequently affected diet quality. Design: Cross-sectional and longitudinal designs. Structural equation models assessed the indirect relationship between restaurant density (≤3 miles (4.8 km) of participant addresses) and dietary quality (Healthy Eating Index 2010 (HEI)) via the frequency of eating restaurant meals, after adjustment for sociodemographics, select health conditions, region, residence duration and area-level income. Setting: Urbanised areas in multiple regions of the USA, years 2000–2002 and 2010–2012. Participants: Participants aged 45–84 years were followed for 10 years (n 3567). Results: Median HEI (out of 100) was 59 at baseline and 62 at follow-up. Cross-sectional analysis found residing in areas with a high density of restaurants (highest ranked quartile) was associated with 52% higher odds of frequently eating restaurant meals (≥3 times/week, odds ratio [OR]:1.52, 95% confidence interval [CI] 1.18-1.98) and 3% higher odds of having lower dietary quality (HEI lowest quartile<54, OR:1.03,CI:1.01-1.06); associations were not sustained in longitudinal analyses. Cross-sectional analysis found 34% higher odds of having lower dietary quality for those who frequently ate at restaurants (OR:1.34,CI:1.12-1.61); and more restaurant meals (over time increase ≥1 times/week) was associated with higher odds of having worse dietary quality at follow-up (OR:1.21,CI:1.00-1.46). Conclusions: Restaurant density was associated with frequently eating out in cross-sectional and longitudinal analyses but was associated with the lower dietary quality only in cross-sectional analyses. Frequent restaurant meals were negatively related to dietary quality. Interventions that encourage less frequent eating out may improve population dietary quality.

scholarly journals Engineering students’ attitudinal beliefs by gender and student division: a methodological comparison of changes over time

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Madison E. Andrews ◽  
Anita D. Patrick ◽  
Maura Borrego
Keyword(s):  
Self Efficacy ◽  
Engineering Students ◽  
Focal Point ◽  
Value Engineering ◽  
Longitudinal Analyses ◽  
Utility Value ◽  
Cross Sectional ◽  
Targeted Interventions ◽  
Significant Difference ◽  
Over Time

Abstract Background Students’ attitudinal beliefs related to how they see themselves in STEM have been a focal point of recent research, given their well-documented links to retention and persistence. These beliefs are most often assessed cross-sectionally, and as such, we lack a thorough understanding of how they may fluctuate over time. Using matched survey responses from undergraduate engineering students (n = 278), we evaluate if, and to what extent, students’ engineering attitudinal beliefs (attainment value, utility value, self-efficacy, interest, and identity) change over a 1-year period. Further, we examine whether there are differences based on gender and student division, and then compare results between cross-sectional and longitudinal analyses to illustrate weaknesses in our current understanding of these constructs. Results Our study revealed inconsistencies between cross-sectional and longitudinal analyses of the same dataset. Cross-sectional analyses indicated a significant difference by student division for engineering utility value and engineering interest, but no significant differences by gender for any variable. However, longitudinal analyses revealed statistically significant decreases in engineering utility value, engineering self-efficacy, and engineering interest for lower division students and significant decreases in engineering attainment value for upper division students over a one-year period. Further, longitudinal analyses revealed a gender gap in engineering self-efficacy for upper division students, where men reported higher means than women. Conclusions Our analyses make several contributions. First, we explore attitudinal differences by student division not previously documented. Second, by comparing across methodologies, we illustrate that different conclusions can be drawn from the same data. Since the literature around these variables is largely cross-sectional, our understanding of students’ engineering attitudes is limited. Our longitudinal analyses show variation in engineering attitudinal beliefs that are obscured when data is only examined cross-sectionally. These analyses revealed an overall downward trend within students for all beliefs that changed significantly—losses which may foreshadow attrition out of engineering. These findings provide an opportunity to introduce targeted interventions to build engineering utility value, engineering self-efficacy, and engineering interest for student groups whose means were lower than average.

scholarly journals Time trends of socioeconomic inequalities in adolescent smoking in Okinawa, Japan, 2008–2016: a repeated cross-sectional study

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Minoru Takakura ◽  
Masaya Miyagi ◽  
Akira Kyan
Keyword(s):  
Time Trends ◽  
Parental Education ◽  
Cross Sectional Study ◽  
Socioeconomic Inequalities ◽  
School Type ◽  
Sectional Study ◽  
Cross Sectional ◽  
Japanese Adolescents ◽  
Index Of Inequality ◽  
Over Time

Abstract Background Smoking among Japanese adolescents has decreased noticeably. However, little is known whether the decreasing trend in adolescent smoking can be seen across all socioeconomic status (SES) groups. This study aimed to examine trends in socioeconomic inequalities in smoking among Japanese adolescents between 2008 and 2016. Methods We conducted a repeated cross-sectional study using data from three surveys of high school students in Okinawa, Japan, in 2008, 2012, and 2016. The study participants consisted of 7902 students in grades 10 through 12 (15–18 years). Smoking was assessed as current cigarette use. SES indicators included familial SES (parental education and family structure) and student’s own SES (school type). To evaluate absolute and relative inequalities, prevalence differences (PDs) and ratios (PRs) between low and high SES groups were estimated. The slope index of inequality (SII) and relative index of inequality (RII) were also calculated. Results Smoking prevalence among boys and girls significantly declined from 11.5% and 6.2% in 2008 to 4.7% and 1.9% in 2016, respectively. Similar decreasing trends in smoking were found among most of the SES groups. The PDs and SII for parental education in boys and family structure in girls decreased over time while those for school type persisted among boys and girls. The PRs and RII for school type in boys increased while those for other SES indicators among both sexes remained stable over time. Conclusions Smoking among Japanese adolescents has been declining and time trends of socioeconomic inequalities in smoking varied by absolute and relative measures. Further policies and/or interventions to reduce smoking inequalities should focus on the context of schools, especially in vocational high schools.

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