Typologies of duocentric networks among low-income newlywed couples

The social networks surrounding intimate couples provide them with bonding and bridging social capital and have been theorized to be associated with their well-being and relationship quality. These networks are multidimensional, featuring compositional (e.g., the proportion of family members vs. friends) and structural characteristics (e.g., density, degree of overlap between spouses' networks). Most previous studies of couple networks are based on partners' global ratings of their network characteristics or network data collected from one member of the dyad. This study presents the analysis of "duocentric networks" or the combined personal networks of both members of a couple, collected from 207 mixed-sex newlywed couples living in low-income neighborhoods of Harris County, TX. We conducted a pattern-centric analysis of compositional and structural features to identify distinct types of couple networks. We identified five qualitatively distinct network types (wife family-focused, husband family-focused, shared friends, wife friend-focused, and extremely disconnected). Couples' network types were associated with the quality of the relationships between couples and their network contacts (e.g., emotional support) but not with the quality of the couples' relationship with each other. We argue that duocentric networks provide appropriate data for measuring bonding and bridging capital in couple networks.

Analysis of the Impact of Detection Threshold Adjustments and Noise Uncertainty on Energy Detection Performance in MIMO-OFDM Cognitive Radio Systems

Due to the capability of the effective usage of the radio frequency spectrum, a concept known as cognitive radio has undergone a broad exploitation in real implementations. Spectrum sensing as a core function of the cognitive radio enables secondary users to monitor the frequency band of primary users and its exploitation in periods of availability. In this work, the efficiency of spectrum sensing performed with the energy detection method realized through the square-law combining of the received signals at secondary users has been analyzed. Performance evaluation of the energy detection method was done for the wireless system in which signal transmission is based on Multiple-Input Multiple-Output—Orthogonal Frequency Division Multiplexing. Although such transmission brings different advantages to wireless communication systems, the impact of noise variations known as noise uncertainty and the inability of selecting an optimal signal level threshold for deciding upon the presence of the primary user signal can compromise the sensing precision of the energy detection method. Since the energy detection may be enhanced by dynamic detection threshold adjustments, this manuscript analyses the influence of detection threshold adjustments and noise uncertainty on the performance of the energy detection spectrum sensing method in single-cell cognitive radio systems. For the evaluation of an energy detection method based on the square-law combining technique, the mathematical expressions of the main performance parameters used for the assessment of spectrum sensing efficiency have been derived. The developed expressions were further assessed by executing the algorithm that enabled the simulation of the energy detection method based on the square-law combining technique in Multiple-Input Multiple-Output—Orthogonal Frequency Division Multiplexing cognitive radio systems. The obtained simulation results provide insights into how different levels of detection threshold adjustments and noise uncertainty affect the probability of detection of primary user signals. It is shown that higher signal-to-noise-ratios, the transmitting powers of primary user, the number of primary user transmitting and the secondary user receiving antennas, the number of sampling points and the false alarm probabilities improve detection probability. The presented analyses establish the basis for understanding the energy detection operation through the possibility of exploiting the different combinations of operating parameters which can contribute to the improvement of spectrum sensing efficiency of the energy detection method.

The impact of dopaminergic treatment over cognitive networks in Parkinson's disease: Stemming the tide?

Dopamine‐replacing therapies are an effective treatment for the motor aspects of Parkinson's disease. However, its precise effect over the cognitive resting‐state networks is not clear; whether dopaminergic treatment normalizes their functional connectivity‐as in other networks‐ and the links with cognitive decline are presently unknown. We recruited 35 nondemented PD patients and 16 age‐matched controls. Clinical and neuropsychological assessments were performed at baseline, and conversion to dementia was assessed in a 10 year follow‐up. Structural and functional brain imaging were acquired in both the ON and practical OFF conditions. We assessed functional connectivity in both medication states compared to healthy controls, connectivity differences within participants related to the ON/OFF condition, and baseline connectivity of PD participants that converted to dementia compared to those who did not convert. PD participants showed and increased frontoparietal connectivity compared to controls: a pattern of higher connectivity between salience (SN) and default‐mode (DMN) networks both in the ON and OFF states. Within PD patients, this higher SN‐DMN connectivity characterized the participants in the ON state, while within‐DMN connectivity prevailed in the OFF state. Interestingly, participants who converted to dementia also showed higher SN‐DMN connectivity in their baseline ON scans compared to nonconverters. To conclude, PD patients showed higher frontoparietal connectivity in cognitive networks compared to healthy controls, irrespective of medication status, but dopaminergic treatment specifically promoted SN‐DM hyperconnectivity.

Cognitive Control-Loop for Elastic Optical Networks with Space-Division Multiplexing

This paper introduces a new solution to improve network performance by decreasing spectrum fragmentation, crosstalk interference, blocking of virtual networks, cost, and link load imbalance. These problems degrade the performance of Elastic Optical Networks with Space-Division Multiplexing. The proposed solution, called Cognitive control loop (CO-OP), is capable of identifying a set of problems and creating plans to mitigate these problems. The CO-OP comprises four functions that employ learning algorithms to identify problems and plan a series of actions to reduce or eliminate them. The results show that the CO-OP can effectively decrease up to 30% the blocking of requests and up to 50% the crosstalk occurrence compared to existing algorithms.

The Mechanism of Physical Activity-induced Amelioration of Parkinson's Disease: A Narrative Review

Physical activity, together with its ameliorative effects on Parkinson's disease (PD) symptoms, remains a relatively unappreciated factor which may be beneficial for the treatment outcome. Contemporary evidence supports the positive effects of non-pharmacological approaches to PD symptom management, in particular the effects of the exercise on both, motor and non-motor symptoms. The aim of the study was to review the mechanisms of exercise-induced amelioration of PD symptoms. Methods: Electronic databases (PubMed, Web of Science and Google Scholar) were searched using the following key words: "Parkinson and physical activity" OR "Parkinson disease and exercise" OR "Parkinson disease and lifestyle factors" OR "Parkinson disease and longevity". A total of 97 studies which investigated PD genetics and various forms of exercise and their etiologic impact on PD were reviewed. The studies were subdivided into four topic groups: 1) genetics of PD, 2) exercise and the brain, 3) physical activity and PD, 4) mind-body interventions, and discussed accordingly. Adequate levels of physical activity are associated with higher quality of life in PD patients. Physical activity may have protective and stimulatory effects for better functional efficiency in higher-level cognitive networks. It can also improve balance and motor functions by improving muscle strength. Given the etiologic evidence of the beneficial effects of physical activity on PD, albeit tentative, a concerted effort to elucidate the processes and outcomes of physical activity on ameliorating symptoms of PD must be undertaken.

Partial recovery of abnormal insula and dorsolateral prefrontal connectivity to cognitive networks in chronic low back pain after treatment

We previously reported that effective treatment of chronic low back pain (CLBP) reversed abnormal brain structure and functional MRI (fMRI) activity during cognitive task performance, particularly in the left dorsolateral prefrontal cortex (DLPFC). Here, we used resting-state fMRI to examine how chronic pain affects connectivity of brain networks supporting cognitive functioning and the effect of treatment in 14 CLBP patients and 16 healthy, pain-free controls (scans were acquired at baseline for all subjects and at 6-months post-treatment for patients and a matched time-point for 10 controls). The main networks activated during cognitive task performance, task-positive network (TPN) and task-negative network (TNN) (aka default mode) network, were identified in subjects' task fMRI data and used to define matching networks in resting-state data. The connectivity of these cognitive resting-state networks was compared between groups, and before and after treatment. Our findings converged on the bilateral insula (INS) as the region of aberrant cognitive resting-state connectivity in patients pretreatment versus controls. These findings were complemented by an independent, data-driven approach showing altered global connectivity of the INS. Detailed investigation of the INS confirmed reduced connectivity to widespread TPN and TNN areas, which was partially restored post-treatment. Furthermore, analysis of diffusion-tensor imaging (DTI) data revealed structural changes in white matter supporting these findings. The left DLPFC also showed aberrant connectivity that was restored post-treatment. Altogether, our findings implicate the bilateral INS and left DLPFC as key nodes of disrupted cognition-related intrinsic connectivity in CLBP, and the resulting imbalance between TPN and TNN function is partially restored with treatment.