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21.
The objective of this study was to determine if a music-based intervention could be successfully used by a group of law enforcement officers and firefighters to improve measures of sleep quality, mood, and daytime function. The Wellness Program Study included 41 male and female first responders who volunteered to participate in the 8-week study investigating the use of a music-based neurofeedback therapy known as Brain Music (BM). Creating the individualized BM recordings required 5 min of brain wave activity from 4 sensors located at F3, F4, C3 and C4 sites. The music consisted of two MP3 files, one for activating and the other for relaxing, where the ratios of peak frequencies in the delta (1–4 Hz) through beta (up to 30 Hz) EEG bands were used to select the notes used and their characteristics (e.g., duration, pitch, amplitude, and symmetry) as a means to individualize the compositions for each subject. Results of the study indicated statistically significant improvements in 4 behavioral measures: sleep quality (94%), insomnia (89%), mood (74%), and daytime function (82%). These results extend earlier insomnia research of music therapy applications from the clinic into an operational setting and lay the groundwork to address many questions concerning neurofeedback interventions targeting stress management and improved job performance. The implication of this study goes beyond the utility of BM in the first responder setting to a broader audience because many persons suffer from sleep problems that negatively impact daytime function and work performance.  相似文献   
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The increasing data provides enough evidences confirming the involvement of free radicals and other reactive oxygen species (ROS) superoxide radical ( . O 2 ? ), nitric oxide (NO . ), hydrogen peroxide (H2O2) and hydroxyl radicals ( . OH) in a number of physiological and pathological processes. Imbalance between levels of ROS resulting in the body and the capacity of antioxidant defense mechanisms occur oxidative stress (OS). OS is related to a number of structural and functional damages to cells and is involved in the pathogenesis of many diseases, including neurodegenerative diseases such as Alzheimer’s disease, Parkinson’s disease (PD), amyotrophic lateral sclerosis, and Huntington disease. Defects in oxidative phosphorylation and oxidative damage play an important role in neurodegenerative diseases. The aim of this study was to investigate some biomarkers of OS such as the level of lipid peroxidation measured as malondialdehyde (MDA) reactive products and activity of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in the blood of PD patients compared with control group of healthy volunteers. By the present research we report higher levels of MDA products and an imbalance in SOD and CAT enzyme activities in PD patients compared to the control group.  相似文献   
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Tropomyosin is a dimer coiled-coil actin-binding protein. Adjacent tropomyosin molecules connect each other ‘head-to-tail’ via an overlap junction and form a continuous strand that winds around an actin filament and controls the actin–myosin interaction. High cooperativity of muscle contraction largely depends on tropomyosin characteristics. Here we summarise experimental evidence that local peculiarities of tropomyosin structure have long-range effects and determine functional properties of the strand, including changes in its bending stiffness and interaction with actin and myosin. Point mutations and posttranslational modifications help to probe the roles of the conserved ‘non-canonical’ residues, clusters of stabilising and destabilising core residues, and core gap in tropomyosin function. The data suggest that tropomyosin structural lability including a diversity of homo- and heterodimers of different isoforms provide a balance of stiffness, flexibility, and strength of interaction with partner sarcomere proteins necessary for fine-tuning of Ca2+ regulation in various types of striated muscles.

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A one-step preparation method for hybrid electromagnetic nanomaterials based on polydiphenylamine (PDPA) and bimetallic Co–Fe particles in the absence and presence of single-walled carbon nanotubes (SWCNT) was proposed. During IR heating of PDPA in the presence of Co(ii) and Fe(iii) salts in an inert atmosphere at T = 450–600 °C, the polycondensation of diphenylamine (DPA) oligomers and dehydrogenation of phenyleneamine units of the polymer with the formation of C Created by potrace 1.16, written by Peter Selinger 2001-2019 N bonds and reduction of metals by evolved hydrogen with the formation of bimetallic Co–Fe particles dispersed in a polymer matrix occur simultaneously. When carbon nanotubes are introduced into the reaction system, a nanocomposite material is formed, in which bimetallic Co–Fe particles immobilized on SWCNT are distributed in the matrix of the polymer. According to XRD data, reflection peaks of bimetallic Co–Fe particles at diffraction scattering angles 2θ = 69.04° and 106.5° correspond to a solid solution based on the fcc-Co crystal lattice. According to SEM and TEM data, a mixture of particles with sizes of 8–30 nm and 400–800 nm (Co–Fe/PDPA) and 23–50 nm and 400–1100 nm (Co–Fe/SWCNT/PDPA) is formed in the nanocomposites. The obtained multifunctional Co–Fe/PDPA and Co–Fe/SWCNT/PDPA nanomaterials demonstrate good thermal, electrical and magnetic properties. The saturation magnetization of the nanomaterials is MS = 14.99–31.32 emu g−1 (Co–Fe/PDPA) and MS = 29.48–48.84 emu g−1 (Co–Fe/SWCNT/PDPA). The electrical conductivity of the nanomaterials reaches 3.5 × 10−3 S cm−1 (Co–Fe/PDPA) and 1.3 S cm−1 (Co–Fe/SWCNT/PDPA). In an inert medium, at 1000 °C the residue is 71–77%.

In a self-organizing system within one stage under IR heating conditions, hybrid nanomaterials are formed with a structure that contains bimetallic Co–Fe particles, free or immobilized on the SWCNT surface, dispersed in the polymer PDPA matrix.  相似文献   
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Serotonin can induce analgesia when injected directly into the brain, but analgesia after peripheral administration has been more difficult to show. The pentobarbital anesthetized mouse (PAM) model, developed to alleviate some of the problems involved in the measurement of tail flick latency, was used to assess the action of peripherally administered serotonin. Mice were anesthetized with about 65 mg/kg of sodium pentobarbital IP and their tail flick latencies measured while they were in stage III anesthesia. In these anesthetized mice, IP serotonin induced a significant analgesia that was much more robust than that found in awake mice. The analgesic effect was dose-dependent from 0.25 mg/kg to 10 mg/kg but was not blocked by the antiopiate naltrexone. Of several psychotropic agents tested, only amitriptyline, mianserin, and trazodone had significant effects on analgesia in the PAM model. The analgesic effect of serotonin was reproduced by the 5HT2 agonist DOI and totally blocked by the 5HT2 antagonist NPP. These results show the utility of the PAM model in studying nonopiate analgesia and suggest that the analgesic action of serotonin is mediated primarily through the 5HT2 receptor.  相似文献   
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