Exposure to relaxing words during sleep promotes slow-wave sleep and subjective sleep quality

Our thoughts alter our sleep, but the underlying mechanisms are still unknown. We propose that mental processes are active to a greater or lesser extent during sleep and that this degree of activation affects our sleep depth. We examined this notion by activating the concept of “relaxation” during sleep using relaxation-related words in 50 healthy participants. In support of our hypothesis, playing relaxing words during non-rapid eye movement sleep extended the time spent in slow-wave sleep, increased power in the slow-wave activity band after the word cue, and abolished an asymmetrical sleep depth during the word presentation period. In addition, participants reported a higher sleep quality and elevated subjective alertness. Our results support the notion that the activation of mental concepts during sleep can influence sleep depth. They provide a basis for interventions using targeted activations to promote sleep depth and sleep quality to foster well-being and health.

Exposure to relaxing words during sleep promotes slow-wave sleep and subjective sleep quality

Our thoughts alter our sleep, but the underlying mechanisms are still unknown. We propose that mental processes are active to a greater or lesser extent during sleep and that this degree of activation affects our sleep depth. We examined this notion by activating the concept of “relaxation” during sleep using relaxation-related words in 50 healthy participants. In support of our hypothesis, playing relaxing words during non-rapid eye movement sleep extended the time spent in slow-wave sleep, increased power in the slow-wave activity band after the word cue, and abolished an asymmetrical sleep depth during the word presentation period. On the subjective level, participants reported a higher sleep quality and elevated alertness ratings. Our results support the notion that the activation of mental concepts during sleep can influence sleep depth and provide a basis for interventions using targeted activations to promote sleep depth and sleep quality to foster well-being and health.

OPTIMIZATION AND BIOCHEMICAL CHARACTERIZATION OF THERMO-ALKALOTOLERANT CELLULASE ENZYME FROM ASPERGILLUS TERREUS PPCF

The aim of this study was to boost the production rate of a novel thermo-alkalotolerant cellulase (FPase) enzyme from the fungal isolate Aspergillus terreus PPCF. Initially, the extracellular FPase activity was 0.166 ± 0.03 UmL-1 in the culture filtrate, which further increased up to 0.91 ± 0.13 UmL-1 under optimized conditions (3% w/v wheat bran and 0.5% w/v ammonium sulfate). Through response surface methodology, the FPase activity was enhanced to 10.78 UmL1 under the cumulative effect of different factors. The zymogram analysis revealed only one activity band, with the molecular weight of ~110 KDa. The optimum pH was 7.0, but the enzyme was stable in a pH range of 4-10. The optimum temperature was 50 °C, but the stability range of the enzyme was 30-90 °C. The maximum effect of Mg2+ was observed on the FPase enzyme. The findings of the present study demonstrate the thermo- and alkalotolerance of the obtained cellulase enzyme, which will be beneficial to the biofuel and other industries.

Production of cutinolytic esterase by Fusarium culmorum grown at different apple cutin concentrations in submerged fermentation

Cutinolytic esterase (i.e., cutinase) is an enzyme that catalyzes the cleavage of ester bonds in cutin and also in diverse soluble and insoluble esters. It has application in several biotechnological areas, acting as biocatalysts in the food industry, in detergents, in biodegradation of polymers and other toxic substances, being important in biorremediation. In this research, specific growth rate, protein content, cutinolytic activity by biochemical tests and polyacrylamide gel electrophoresis, and growth and enzymatic kinetic parameters were determined for F. culmorum grown at different apple cutin concentrations (0.2, 2 and 20 g/L) in submerged fermentation. It was observed that biomass, protein content and enzymatic activity enhanced as cutin concentration increased in the media. A cutinase activity band of around 65 KDa was observed in zymograms of different cutin concentration. An additional cutinase activity band of around 90 KDa was also observed in zymograms of F. culmorum grown in 20 g of apple cutin/L. These studies showed that F. culmorum used apple cutin as the sole carbon source, which acted as a cutinase inducer. The highest-yielding parameters of cutinase were observed in 2 g of apple cutin/L. This research showed promising results in the cutinase induction for F. culmorum using a low concentration of apple cutin.

Differences in the solar cycle variability of simple and complex active regions during 1996–2018

Aims. Our aim is to examine the solar cycle variability of magnetically simple and complex active region. Methods. We studied simple (α and β) and complex (βγ and βγδ) active regions based on the Mount Wilson magnetic classification by applying our newly developed daily approach. We analyzed the daily number of the simple active regions (SARs) and compared that to the abundance of the complex active regions (CARs) over the entire solar cycle 23 and cycle 24 until December 2018. Results. We show that CARs evolve differently over the solar cycle from SARs. The time evolution of SARs and CARs on different hemispheres also shows differences, even though on average their latitudinal distributions are shown to be similar. The time evolution of SARs closely follows that of the sunspot number, and their maximum abundance was observed to occur during the early maximum phase, while that of the CARs was seen roughly two years later. We furthermore found that the peak of CARs was reached before the latitudinal width of the activity band starts to decease. Conclusion. Our results suggest that the active region formation process is a competition between the large-scale dynamo (LSD) and the small-scale dynamo (SSD) near the surface, the former varying cyclically and the latter being independent of the solar cycle. During solar maximum, LSD is dominant, giving a preference to SARs, while during the declining phase the relative role of SSD increases. Therefore, a preference for CARs is seen due to the influence of the SSD on the emerging flux.

Induced and Evoked Properties of Vibrotactile Adaptation in the Primary Somatosensory Cortex

Prolonged exposure to afferent stimulation (“adaptation”) can cause profound short-term changes in the responsiveness of cortical sensory neurons. While several models have been proposed that link adaptation to single-neuron dynamics, including GABAergic inhibition, the process is currently imperfectly understood at the whole-brain level in humans. Here, we used magnetoencephalography (MEG) to examine the neurophysiological correlates of adaptation within SI in humans. In one condition, a 25 Hz adapting stimulus (5 s) was followed by a 1 s 25 Hz probe (“same”), and in a second condition, the adapting stimulus was followed by a 1 s 180 Hz probe (“different”). We hypothesized that changes in the mu-beta activity band (reflecting GABAergic processing) would be modulated differently between the “same” and “different” probe stimuli. We show that the primary somatosensory (SI) mu-beta response to the “same” probe is significantly reduced (p=0.014) compared to the adapting stimulus, whereas the mu-beta response to the “different” probe is not (p=n.s.). This reduction may reflect sharpening of the spatiotemporal pattern of activity after adaptation. The stimulus onset mu-beta response did not differ between a 25 Hz adapting stimulus and a 180 Hz probe, suggesting that the mu-beta response is independent of stimulus frequency. Furthermore, we show a sustained evoked and induced desynchronization for the duration of the adapting stimulus, consistent with invasive studies. Our findings are important in understanding the neurophysiology underlying short-term and stimulus-induced plasticity in the human brain and shows that the brain response to tactile stimulation is altered after only brief stimulation.

Two Coupled Circadian Oscillators Are Involved in Nonphotic Acceleration of Reentrainment to Shifted Light Cycles in Mice

The onset and offset of an activity band in the circadian behavioral rhythm are known to differentially reentrain to shifted light-dark cycles (LD). Differential reentrainment could be explained by different light responsivities of circadian oscillators underlying these phase-markers. In contrast, reentrainment is accelerated by exposure to nonphotic time cues such as timed wheel-running. However, the relationship between the 2 oscillators and nonphotic acceleration of reentrainment is largely unknown. We examined phase-shifts of the mouse behavioral rhythm in response to an 8-h phase-advanced shift of LD and effects of behavioral interventions: maintained in a home cage (HC), exposed to a running wheel (RW) in HC (HC+RW), transferred to a new cage (NC), and exposed to RW in NC (NC+RW). Each intervention was given for 3h from the beginning of the shifted dark period and repeated for 4 days. Following the last dark period, the mice were released into constant darkness (DD). As a result, activity onset and offset were differentially phase-shifted. The activity onset on the first day of DD (DD1) was phase-advanced from the baseline slightly in HC and HC+RW, substantially in NC+RW, but not significantly in NC. The amount of phase-shift was significantly larger in the NC+RW than in the other groups. In contrast, the activity offset was significantly advanced in all groups by 6 to 8 h. The differential phase-shifts resulted in shortening of the activity band (α compression). The α compression was gradually relieved upon exposure to DD (α decompression), and the activity band finally became stable. Interestingly, the magnitude of phase-shifts of activity offset, but not of activity onset, in the following DD was negatively correlated with the extent of α compression in DD1. These findings indicate that the 2 circadian oscillators underlying activity onset and offset are involved in asymmetric phase-shifts and nonphotic acceleration of reentrainment.

Preliminary studies on ribonucleases from Poa pratensis seeds

Ribonuclease was extracted from <i>Poa pratensis</i> seeds with 0.1 M acetate buffer, pH 5.1, and then precipitated with alcohol. The enzyme was separated into 5 fractions (I-V) after chromatography on DEAE-cellulose at pH 5.1. The enzymes were stable at 50°C, at pH 7.1. The activity of ribonucleases I, II, III and V were optimal at pH 7.1-7.3, and that of ribonuclease IV at pH 8.1. Ali enzymes were inhibited by Ca²⁺ and EDTA. Mg²⁺ inhibited the activity of ribonucleases II, III, IV, and had no influence on that of ribonucleases I and V. Ribonucleases IV and V showed only one activity band in disc electrophoresis, whereas ribonucleases, I, II and III were found to be heterogenous.