Automatic Modulation Recognition Based on Hybrid Neural Network

Recognizing signals is critical for understanding the increasingly crowded wireless spectrum space in noncooperative communications. Traditional threshold or pattern recognition-based solutions are labor-intensive and error-prone. Therefore, practitioners start to apply deep learning to automatic modulation classification (AMC). However, the recognition accuracy and robustness of recently presented neural network-based proposals are still unsatisfactory, especially when the signal-to-noise ratio (SNR) is low. In this backdrop, this paper presents a hybrid neural network model, called MCBL, which combines convolutional neural network, bidirectional long-short time memory, and attention mechanism to exploit their respective capability to extract the spatial, temporal, and salient features embedded in the signal samples. After formulating the AMC problem, the three modules of our hybrid dynamic neural network are detailed. To evaluate the performance of our proposal, 10 state-of-the-art neural networks (including two latest models) are chosen as benchmarks for the comparison experiments conducted on an open radio frequency (RF) dataset. Results have shown that the recognition accuracy of MCBL can reach 93% which is the highest among the tested DNN models. At the same time, the computation efficiency and robustness of MCBL are better than existing proposals.

Deadlines and Memory Limitations

This paper presents the results of two natural field experiments at a dental clinic. Guided by a simple theoretical model, we exogenously vary deadlines and associated rewards for arranging checkup appointments. Our data show strong and systematic effects of deadlines on patients’ behavior. Imposing deadlines induces patients to act earlier and at a persistently higher frequency than without a deadline. We further document that individuals systematically respond to deadlines even if these are not tied to explicit rewards. Several of our findings suggest that individuals’ responses to deadlines are shaped by limitations in memory and attention. Our results illustrate that deadlines can be a powerful management tool to encourage timely task completion and to increase the cost effectiveness of performance-contingent rewards. This paper was accepted by Axel Ockenfels, behavioral economics and decision analysis.

Actigraphy Measured Physical Activity on Cognitive Functioning in Older Adults

Physical activity may preserve cognitive functioning in older adults. This study examined associations between objectively measured physical activity and cognitive functioning. We recruited participants (Mage = 75.38 years, SD = 5.99) with (N=26) and without (N=181) cognitive impairment from the University of Kansas Alzheimer’s Disease Center (KU-ADC). We collected cognitive data representing verbal memory, attention, and executive function. Accelerometers (Actigraph GT9X) were used to measure physical activity 24 hours a day for 7 days in a free-living environment. Physical activity was categorized as moderate to vigorous physical activity (MVPA) based on the Freedson (2011) Adult Vector Magnitude cut points. The association between cognitive functioning and total MVPA was evaluated by using multiple regression. We used factor analysis to create three composite scores (verbal memory, attention, executive function) from 11 individual cognitive tests. Compared to verbal memory and attention, results indicate that total MVPA was more strongly associated with executive function (β = 0.001, p = .024). These findings are consistent with the literature suggesting that executive function in older adults may benefit from physical activity. Future research should investigate the physiological mechanisms by which MVPA benefits executive function in contrast to types of activity that might benefit verbal memory and attention.

Validation of Chinese Version of SKT (Syndrom Kurztest): A Short Cognitive Performance Test for the Assessment of Memory and Attention

(1) Background: The SKT (Syndrom Kurztest) is a short cognitive performance test that consists of nine subtests and assesses deficits of memory and attention. This study was aimed at exploring the SKT target population in China and evaluating the reliability and validity of the Chinese version of the SKT; (2) Methods: A total of 1624 patients aged over 60 years old were recruited in the Sixth People’s Hospital in Shanghai. The SKT raw scores were recorded. Cronbach’s alpha coefficient was determined to assess the internal consistency reliability of the SKT. Principal factor analysis was performed to evaluate the factor structure of the SKT subtests. Correlation analyses were carried out to confirm the relationship between the modified SKT and standardized neuropsychological tests. The influence of age and educational years on SKT raw scores were detected using multiple regression analyses. Validations of the SKT subtests for detecting Mild Cognitive Impairment (MCI) from Negative Control(NC)(were determined by Receiver operating characteristic (ROC) curves; (3) Results: The internal consistency among the subtests’ scores was high: Cronbach’s α = 0.827. The SKT memory test provided a high predictive validity in detecting aMCI with a sensitivity of 90.1% and specificity of 79.3%. (4) Conclusions: Based on our experience with 1624 elderly patients in Shanghai, the Chinese version of SKT has good stability and may be a reliable and valid screening tool for detecting MCI.

nalysis of Impact of Alcohol on Brain's Activity

Electroencephalography is an electrophysiological monitoring process to capture electrical activity on the scalp that has been shown to represent the macroscopic activity of the surface layer of the brain underneath. It is typically non-invasive, with the electrodes placed along the scalp. Computer programs in different programming language such as MATLAB, Python are used to simulate and study brain signals. This thesis focuses on utilizing Python, an open-source programming language to understand the impact of alcohol on one’s memory and attention and comparing them with non-alcoholic brain. To carry out this research, we are using open-source EEG data collected from alcoholic and non-alcoholic subjects subjected to visual stimuli. Experiments are carried out to observe spatial patterns related to both groups' brain activity and their association with different region of brain such as memory, attention, somatosensory, and emotional regulation regions. Besides the spatial pattern, we are also focusing to find source signals and their association with respect to attention region to understand the impact of alcohol on one’s attention function. Finally, the optimal sources based on optimal alpha and gamma rhythms are estimated. For these optimal source channels, we estimated time-frequency based spectrogram to understand the association of other band powers for both groups. Beta power activities from these spectrograms are analyzed for both groups to understand attention-deficit caused by alcohol consumption. By analyzing the results from the experiments can help us understand the impact of alcohol on one's brain's activity.

Exposure to 3′Sialyllactose-Poor Milk during Lactation Impairs Cognitive Capabilities in Adulthood

Breast milk exerts pivotal regulatory functions early in development whereby it contributes to the maturation of brain and associated cognitive functions. However, the specific components of maternal milk mediating this process have remained elusive. Sialylated human milk oligosaccharides (HMOs) represent likely candidates since they constitute the principal neonatal dietary source of sialic acid, which is crucial for brain development and neuronal patterning. We hypothesize that the selective neonatal lactational deprivation of a specific sialylated HMOs, sialyl(alpha2,3)lactose (3′SL), may impair cognitive capabilities (attention, cognitive flexibility, and memory) in adulthood in a preclinical model. To operationalize this hypothesis, we cross-fostered wild-type (WT) mouse pups to B6.129-St3gal4tm1.1Jxm/J dams, knock-out (KO) for the gene synthesizing 3′SL, thereby providing milk with approximately 80% 3′SL content reduction. We thus exposed lactating WT pups to a selective reduction of 3′SL and investigated multiple cognitive domains (including memory and attention) in adulthood. Furthermore, to account for the underlying electrophysiological correlates, we investigated hippocampal long-term potentiation (LTP). Neonatal access to 3′SL-poor milk resulted in decreased attention, spatial and working memory, and altered LTP compared to the control group. These results support the hypothesis that early-life dietary sialylated HMOs exert a long-lasting role in the development of cognitive functions.

Efficacy of TMS and Cognitive Training in Mild Cognitive Impairment: A Pilot Study

Purpose: Transcranial magnetic stimulation (TMS) is a noninvasive brain stimulation technique with the potential to improve memory. Mild cognitive impairment (MCI), which still lacks a specific therapy, is a clinical syndrome associated with increased risk of dementia. This study aims to assess the effects of deep TMS (dTMS) on a group of 10 patients diagnosed with amnesic MCI. Methods: We compared the effects of TMS COG treatment (dTMS delivered with H7 helmet for ten daily sessions together with cognitive training of memory and attention), with those of COG treatment (cognitive training alone) of the same duration. Results: Neuropsychological evaluation at baseline, after TMS COG treatment, after COG treatment and at six months follow up, compared with ANOVA, revealed a significant group-by-time interaction (𝑝 = 0.05), favoring the TMS COG treatment for memory tests. The improvement was kept after six months. Other neuropsychological tests were not significantly affected by treatment. Conclusions: These findings suggest that dTMS might be effective as a therapy for MCI and probably a tool to delay cognitive deterioration.

THE EFFECTIVENESS OF OZONE THERAPY IN THE REHABILITATION OF PATIENTS WITH DISORDERS OF THE CENTRAL NERVOUS SYSTEM AFTER SUFFERING COVID-ASSOCIATED PNEUMONIA

The consequences of the transferred new coronavirus infection are currently not well understood, but the neurotropicity of SARS-CoV-2 is beyond doubt. In the manifestations of postcoid syndrome, damage to the central nervous system is dominant and requires timely diagnosis and correction, incl. at the rehabilitation stage of medical care. The introduction of highly effective non-drug methods of treatment with a small number of side effects is an urgent task of modern medicine. Such methods of treatment can include ozone therapy - the use of an ozone-oxygen mixture (ACS) for therapeutic purposes, which significantly improves blood microcirculation and oxygenation of ischemic tissues due to its fibrinolytic activity and antiaggregatory properties, and therapeutic doses of ozone are able to correct the lipid profile of patients due to reducing atherogenic lipoproteins, triglycerides and cholesterol. In the range of therapeutic concentrations, ozone exhibits immunomodulatory, anti-inflammatory, bactericidal, antiviral, and detoxification effects. This article presents the experience of using ozone therapy in patients who have undergone covid-associated pneumonia (CT1-CT4) with postcoid syndrome and a predominant lesion of the central nervous system. The analysis of the dynamics of symptoms in a group of patients who underwent a course of ozone therapy in comparison with a group where ozone therapy was contraindicated is presented. The defeat of the central nervous system was represented by the following syndromes and symptoms, both individually and in combination: - cerebrasthenic syndrome, incl. anxiety, insomnia, decreased or lack of appetite, unstable mood background, weakness, fatigue - 94% - cerebral syndrome (headaches, constant "fog in the head", less often dizziness, decreased memory and attention, impaired sensitivity like anosmia, hyposmia) - 62%, incl. loss of memory and attention was observed in 42%, anosmia and hyposmia occurred in 11% of cases. The severity of certain symptoms was manifested depending on the age, the severity of the disease, the timing of the beginning of rehabilitation measures and the comorbid background. Diagnostics of the lesion of the central nervous system by coronavirus in patients was carried out by the methods of questioning complaints, dynamic observation, using the questionnaire for assessing the quality of life EQ-5D. In addition, in both groups of patients, the assessment of the severity of the main syndromes in points from 0 to 10 was carried out using a questionnaire at the beginning of the rehabilitation course and at the end of it. Evaluation of the results at discharge was carried out using the Pearson correlation coefficient. The use of an ozone-oxygen gas mixture in a comprehensive rehabilitation program for patients with postcoid syndrome and a predominant CNS lesion can reduce the intensity or completely stop cerebroasthenic and cerebral syndromes, completely restore taste and smell, and improve certain cognitive functions. This will improve the quality of life of patients, their social adaptation and reduce the drug load. The syndromic complex of CNS lesions, which remains in a certain volume, even after a comprehensive rehabilitation program with ozone therapy, indicates the need for long-term follow-up, clinical examination and medical rehabilitation of patients after a new coronavirus infection.

Validation of Chinese Version of SKT (Syndrom Kurztest): A Short Cognitive Performance Test for the Assessment of Memory and Attention.

Aim: The SKT (Syndrom Kurztest) is a short cognitive performance test that consists of nine subtests and assesses deficits of memory and attention. It was aimed at exploring the SKT target population in China and to evalute the reliability and validity of the Chinese version of SKT.Method: A total of 1624 patients (599 cognitively normal controls, 359 subjectively cognitively impairment, 666 individuals with mild cognitive impairment) aged over 60 years old were recruited in the Sixth People’s Hospital in Shanghai. Cognitive screening tests (Chinese version of SKT, MMSE, MoCA-BC, ACE-III, AVLT, BVMT-R) and global functional tests (ECOG, ADL) were carried out. The SKT raw scores were recorded. Cronbach’s alpha coefficient was determined to assess the internal consistency reliability of the SKT. Principal factor analysis was performed to evaluate the factor structure of the SKT subtests. Correlation analyses were carried out to confirm the relationship between the modified SKT and standardized neuropsychological tests. The influence of age and educational years on SKT raw scores were detected using multiple regression analyses. Validations of the SKT subtests for detecting MCI from NC were determined by Receiver operating characteristic (ROC) curves.Result: The internal consistency among the subtests’ scores was high: Cronbach’s α=0.827. The dimension reduction analysis showed the good factor structure of SKT subtests. Correlation analysis indicated the SKT raw scores of each subtest was negatively correlated with the corresponding MMSE and MoCA-B score. Correlation analysis revealed that age and education years were correlated to SKT raw scores (all p <0.001). We separated the participants into four subgroups according to educational years and age. Among the four groups, The old-old with higher educational level (group 4) had the largest area under the ROC curve (AUC) for SKT memory test, 0.821(95%CI: 0.747,0.876), with sensitivity 84.3% and specificity 62.1%. SKT memory test provided a high predictive validity in detecting aMCI with sensitivity 90.1% and specificity 79.3%.Conclusion: Based on our experience with 1624 old patients in Shanghai, the Chinese version of SKT has good stability which might be a reliable and valid screening tool for detecting MCI. However, test results must be interpreted with caution considered individuals’ age and educational level.

Possibilities of daytime anxolytics in the correction of residual neurological manifestations of COVID-19

Introduction. In addition to acute manifestations, coronavirus infection is characterized by long-lasting symptoms: asthenia, somatic vegetative manifestations, sleep disorders and psychoemotional background, the question of therapeutic correction of which is especially relevant.The aim of the study was to study the mental, somatoform and cognitive aspects of anxiety disorders after coronavirus infection during treatment with tofizopam (Grandaxin®) at 150 mg / day.Materials and methods. The study involved patients who had a new coronavirus infection, who 4 weeks after the end of treatment for the underlying disease had complaints that suggest the presence of an anxiety disorder. The Hamilton scale was used to assess the level of anxiety. The patients were examined before the start of treatment, after 2, 4 and 6 weeks of therapy.Results. Prior to the start of therapy, all patients had an overall high level of anxiety: the average HAM-A score was 31.72 ± 2.24 points. At the end of Grandaxin® therapy, all patients showed a decrease in the level of anxiety: the average score for HAM-A was 12.68 ± 2.04 points (p < 0.001). At the end of the course of therapy, patients noted an increase in mental performance, improved memory and attention, that is, a decrease in the severity of cognitive disorders associated with anxiety was> distinct – the average score on the “cognitive disorders” subscale decreased three times – from 1.6 ± 0.12 to 0.5 ± 0.09 (p˂0.001).Conclusions. Disorders of the psychoemotional background (more often in the form of increased personal anxiety), sleep disorders, autonomic disorders, asthenic syndrome significantly affect the quality of life of patients who have suffered a new coronavirus infection. A comprehensive approach is needed in the clinical diagnosis of the long-term consequences of a new coronavirus infection and their subsequent correction with drug therapy.