FQPSK-B viterbi receiver

An FQPSK-B receiver uses a simplified trellis system which uses combinations of FQPSK-B waveforms to correlate against an input signal. This enables reduction of the number of correlators that are used and the number of comparisons that are made by the correlators

Mechanistic distinctions between agrin and laminin-1 induced aggregation of acetylcholine receptors

BACKGROUND: One of the earliest steps in synaptogenesis at the neuromuscular junction is the aggregation of nicotinic acetylcholine receptors at the postsynaptic membrane. This study presents quantitative analyses of receptor and α-Dystroglycan aggregation in response to agrin and laminin-1, alone or in combination. RESULTS: Both laminin and agrin increased overall expression of receptors on the plasma membrane. Following a 24 hour exposure, agrin increased the number of receptor aggregates but did not affect the number of α-Dystroglycan aggregates, while the reverse was true of laminin-1. Laminin also increased receptor concentration within aggregates, while agrin had no such effect. Finally, the spatial distribution of aggregates was indistinguishable from random in the case of laminin, while agrin induced aggregates were closer together than predicted by a random model. CONCLUSIONS: Agrin and laminin-1 both increase acetylcholine receptor aggregate size after 24 hours, but several lines of evidence indicate that this is achieved via different mechanisms. Agrin and laminin had different effects on the number and density of receptor and α-Dystroglycan aggregates. Moreover the random distribution of laminin induced (as opposed to agrin induced) receptor aggregates suggests that the former may influence aggregate size by simple mass action effects due to increased receptor expression

Chronic Ankle Instability Subjects Demonstrate Lower Rate of Torque Development in Ankle Eversion, Hip Abduction Muscles Compared to Healthy, Coper Groups

Chronic ankle instability (CAI) is a pathological condition characterized by repeated lateral ankle sprains. Many ankle sprains are not a singular occurrence and can lead to perpetual disability, with some patients reporting repeated episodes of the ankle “giving way” during activity. CAI is multifactorial in nature, with contributors such as ligamentous laxity, strength deficit, and proprioceptive impairment (1). Each of these contributors negatively affects the muscles of the ankle complex. Rate of torque development (RTD) is a metric demonstrating explosive muscle capability, and is related to measurement of maximal voluntary isometric contraction (MVIC). RTD is a more accurate reflection of functional strength than MVIC because peak torque generally occurs 300ms or more after the onset of torque generation (2) while the time available for torque production in a functional daily movement context is generally between 50-250ms (3). RTD is generally measured within the first 200ms of the trial and therefore better captures the muscle’s ability to generate strength for daily activities. Understanding the relationship between RTD of the ankle evertor/invertor muscles and hip abductor muscles in individuals with CAI against healthy controls will better inform rehabilitation strategies and provide a benchmark of improvement for individuals recovering from CAI. PURPOSE: The purpose of this study was to better understand how CAI affects the force production capabilities of the ankle evertors/invertors, as well as the hip abductors. We hypothesized that individuals with CAI would demonstrate lower RTD in all three muscle groups in comparison to healthy and coper controls. METHODS: A total of 58 males and females participated in this study, and participants were divided into three cohorts. The first was a CAI patient group, a “coper” group, defined as individuals who can return to pre-injury levels of performance after LAS, and a healthy control group. CAI individuals and LAS copers were identified using the guidelines provided by the International Ankle Consortium (4). Subject exclusion criteria included previous history of lower extremity surgery, fracture, neurological disease affecting the lower extremity, or any injury to the lower extremity in the 3 months leading up to the study. Before data was obtained participants were familiarized with experimental procedures and protocols. Signed consent was obtained from each subject prior to data collection. The study was approved by the university institutional review board (Approval number: F2019-338). The study design required two visits from the subjects. The first visit was to familiarize subjects with the ankle eversion, inversion, and hip abduction movements they would be required to perform. On this day patients were also made familiar with the Biodex dynamometer (System Pro 4, Biodex Medical Systems, Inc., Shirley, NY; sampling rate: 100 Hz). On the second day subjects were seated on the dynamometer and performed 3 maximal voluntary isometric contractions (MVIC) of each movement. Patients were instructed to perform the movements as quickly as possible and to hold each trial for 5 seconds. Three trials were collected for each movement, with a minute separating each trial. Subjects were encouraged to give maximal effort through verbal cues. RTD and MVIC were calculated from each torque-time curve using custom code written in MatLab (MathWorks 2021a, Natick, MA). RTD was defined as the rate of change of the first 200ms of each trial; MVIC was defined as the peak value of each trial. RTD and MVIC values were averaged for each subject. RESULTS: No statistically significant differences in sex, age, height, or mass were detected among subjects (Table 1). Table 2 shows mean RTD for each group for the ankle eversion, inversion, and hip abduction movements. Notable results from Table 2 include the finding that CAI patients demonstrated significantly lower RTD than healthy controls (p = .02) and lower RTD than LAS copers (p = .03). Furthermore, CAI patients showed lower hip abductor RTD than healthy controls (p = .04). Table 3 shows MVIC data for each group for each movement and demonstrates that CAI patients showed significantly lower MVIC of the ankle eversion muscles than healthy controls (p = .02). No statistically significant differences in any strength metrics were detected between LAS copers and healthy controls, nor were there differences detected between groups in the ankle inversion movement. DISCUSSION: The primary finding from this study was that CAI ankle eversion RTD was significantly lower than RTD in healthy controls. This is significant because it provides insight on the adverse effects of repeated LAS on the muscles of the ankle complex. One of the factors determining RTD is the force transmission capabilities of the tendinous structures (10), and it is possible that the stretching of the ankle ligaments during LAS negatively affects its ability to efficiently transmit force generated from the muscle. Given the correlation between CAI patients and decreased RTD of ankle eversion muscles, it is possible that focusing on improvement in RTD of this muscle group could improve CAI symptoms. Numerous studies have focused on modalities targeted at improving RTD of the leg extensors muscle groups with generally positive results (5, 9), the majority of which include protocols that would be easily modifiable to the ankle eversion muscle group. Another notable finding from this study was that RTD of the hip abductors in the CAI group was significantly less than that of the healthy group. Although studies exist that have measured maximal hip abduction isometric strength in CAI groups, to our knowledge this is the first study analyzing the RTD of hip abduction. Our findings of deficits in hip abduction strength coincide with those of previous studies (6-8). Whether deficits in hip abduction strength increase potential for LAS or arise as a result of CAI is unclear, but it is becoming evident that the two factors are related. This is a promising area of CAI research and further study is required to fully elucidate the relationship between CAI and hip abductor strength. CONCLUSION: RTD of the ankle evertors in individuals with CAI is significantly lower than in LAS copers and healthy controls. Additionally, CAI patients demonstrated significantly lower RTD in hip abduction than healthy controls. While the need for exploring muscle force production capabilities in individuals with CAI persists, we suggest exploring modalities targeted at improving ankle eversion and hip abduction strength in patients with CAI. It is possible that improving strength in these areas will help return CAI patients to pre-injury levels of function and further our understanding of CAI

Scoping Review of Racial and Ethnic Representation of Participants in Mental Health Research Conducted in the Perinatal Period During the COVID-19 Pandemic

OBJECTIVE: To identify the racial and ethnic representation of participants in mental health research conducted in the perinatal period during the COVID-19 pandemic. DATA SOURCES: MEDLINE, CINAHL, Cochrane Library, PsycINFO, Scopus, Web of Science. STUDY SELECTION: We included peer-reviewed research articles in which researchers reported mental health outcomes of women during the perinatal period who were living in the United States or Canada during the COVID-19 pandemic. We included 25 articles in the final review. DATA EXTRACTION: We extracted the citation, publication date, design, aim, country of origin, participant characteristics, sampling method, method of measurement of race and ethnicity, and mental health outcome(s). DATA SYNTHESIS: The combined racial and ethnic representation of the 16,841 participants in the included studies was White (76.5%), Black (9.8%), other/multiracial (6.2%), Asian (3.9%), Hispanic/Latina (2.6%), Indigenous or Ethnic Minority Canadian (0.9%), and Native American or Alaska Native (0.1%). Most studies were conducted in the United States, used a cross-sectional design, and incorporated social media platforms to recruit participants. Depression, anxiety, and stress were the most frequently assessed mental health outcomes. CONCLUSION: Relatively few women of color who were pregnant or in the postpartum period during the pandemic participated in mental health research studies. Future studies should develop intentional recruitment strategies to increase participation of women of color. Researchers should use updated guidance on reporting race and ethnicity to accurately represent every participant, minimize misclassification of women of color, and report meaningful results

HICSS Panel Report on Cognitive Foreshadowing: Next Steps in Applying Neuroscience and Cognitive Science to Information Systems Research

The use of neurophysiological tools in the information systems domain has received increased attention over the last decade. The Hawaii International Conference on System Sciences has helped provide a home for rigorously exploring such work through related minitracks and symposia. This paper reports on a panel presented at the 49th HICSS conference held in 2016 during a symposium organized to help orient interested researchers to the usefulness of cognitive neuroscience in IS research. This paper first introduces the rise in the IS discipline for integrating the methodologies and tools of cognitive neuroscience. It then presents individual viewpoints from the varying panel members at the symposium as they addressed questions of longevity, applicability, and next steps for the neuroIS subdiscipline. The four panel members included Alan Dennis, Angelika Dimoka, Allen Lee, and Ofir Turel

Observation of Collective Excitations of the Dilute 2D Electron System

We report inelastic light scattering measurements of dispersive spin and charge density excitations in dilute 2D electron systems reaching densities less than 10^{10} cm^{-2}. In the quantum Hall state at nu=2, roton critical points in the spin inter--Landau level mode show a pronounced softening as r_s is increased. Instead of a soft mode instability predicted by Hartree--Fock calculations for r_s ~ 3.3, we find evidence of multiple rotons in the dispersion of the softening spin excitations. Extrapolation of the data indicates the possibility of an instability for r_s >~ 11.Comment: Submitted to Physical Review Letter

Support for Aboriginal health services in reducing harms from alcohol : 2-year service provision outcomes in a cluster randomized trial

Background and aims There is a higher prevalence of unhealthy alcohol use among Indigenous populations, but there have been few studies of the effectiveness of screening and treatment in primary health care. Over 24 months, we tested whether a model of service-wide support could increase screening and any alcohol treatment. Design Cluster-randomized trial with 24-month implementation (12 months active, 12 months maintenance). Setting Australian Aboriginal Community Controlled primary care services. Participants Twenty-two services (83 032 clients) that use Communicare practice software and see at least 1000 clients annually, randomized to the treatment arm or control arm. Intervention and comparator Multi-faceted early support model versus a comparator of waiting-list control (11 services). Measurements A record (presence = 1, absence = 0) of: (i) Alcohol Use Disorders Identification Test—Consumption (AUDIT-C) screening (primary outcome), (ii) any-treatment and (iii) brief intervention. We received routinely collected practice data bimonthly over 3 years (1-year baseline, 1-year implementation, 1-year maintenance). Multi-level logistic modelling was used to compare the odds of each outcome before and after implementation. Findings The odds of being screened within any 2-month reference period increased in both arms post-implementation, but the increase was nearly eight times greater in early-support services [odds ratio (OR) = 7.95, 95% confidence interval (CI) = 4.04–15.63, P < 0.001]. The change in odds of any treatment in early support was nearly double that of waiting-list controls (OR = 1.89, 95% CI = 1.19–2.98, P = 0.01) but was largely driven by decrease in controls. There was no clear evidence of difference between groups in the change in the odds of provision of brief intervention (OR = 1.95, 95% CI = 0.53–7.17, P = 0.32). Conclusions An early support model designed to aid routine implementation of alcohol screening and treatment in Aboriginal health services resulted in improvement of Alcohol Use Disorders Identification Test—Consumption screening rates over 24 months of implementation, but the effect on treatment was less clear

GAD1 Upregulation Programs Aggressive Features of Cancer Cell Metabolism in the Brain Metastatic Microenvironment

The impact of altered amino acid metabolism on cancer progression is not fully understood. We hypothesized that a metabolic transcriptome shift during metastatic evolution is crucial for brain metastasis. Here, we report a powerful impact in this setting caused by epigenetic upregulation of glutamate decarboxylase 1 (GAD1), a regulator of the GABA neurotransmitter metabolic pathway. In cell-based culture and brain metastasis models, we found that downregulation of the DNA methyltransferase DNMT1 induced by the brain microenvironment-derived clusterin resulted in decreased GAD1 promoter methylation and subsequent upregulation of GAD1 expression in brain metastatic tumor cells. In a system to dynamically visualize cellular metabolic responses mediated by GAD1, we monitored the cytosolic NADH:NAD+ equilibrium in tumor cells. Reducing GAD1 in metastatic cells by primary glia cell coculture abolished the capacity of metastatic cells to utilize extracellular glutamine, leading to cytosolic accumulation of NADH and increased oxidative status. Similarly, genetic or pharmacologic disruption of the GABA metabolic pathway decreased the incidence of brain metastasis in vivo Taken together, our results show how epigenetic changes in GAD1 expression alter local glutamate metabolism in the brain metastatic microenvironment, contributing to a metabolic adaption that facilitates metastasis outgrowth in that setting