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There have been mixed reports on the beneficial effects of meditation in cardiovascular disease (CVD), which is widely considered the leading cause of death worldwide.To clarify the role of meditation in modulating the heart-brain axis, we implemented an extreme phenotype strategy, i.e., Tibetan monks (BMI30) who practised 19.20 ± 7.82 years of meditation on average and their strictly matched non-meditative Tibetan controls. Hypothesis-free advanced proteomics strategies (Data Independent Acquisition and Targeted Parallel Reaction Monitoring) were jointly applied to systematically investigate and target the plasma proteome underlying meditation. Total cholesterol, low-density lipoprotein cholesterol (LDL-C), apolipoprotein B (Apo B) and lipoprotein (a) [Lp(a)] as the potential cardiovascular risk factors were evaluated. Heart rate variability (HRV) was assessed by electrocardiogram.Obesity, hypertension, and reduced HRV is offset by long-term meditation. Notably, meditative monks have blood pressure and HRV comparable to their matched Tibetan controls. Meditative monks have a protective plasma proteome, related to decreased atherosclerosis, enhanced glycolysis, and oxygen release, that confers resilience to the development of CVD. In addition, clinical risk factors in plasma were significantly decreased in monks compared with controls, including total cholesterol, LDL-C, Apo B, and Lp(a).To our knowledge, this work is the first well-controlled proteomics investigation of long-term meditation, which opens up a window for individuals characterized by a sedentary lifestyle to improve their cardiovascular health with an accessible method practised for more than two millennia.See the Acknowledgements section.

Meditation has been a spiritual and healing practice in the East for thousands of years. However, the neurophysiologic mechanisms underlying its traditional form remain unclear. In this study, we recruited a large sample of monks (n = 73) who practice Tibetan Buddhist meditation and compared with meditation-naive local controls (n = 30). Their electroencephalography (EEG) and electrocardiogram signals were simultaneously recorded and blood samples were collected to investigate the integrative effects of Tibetan Buddhist on brain, heart, and proteomics. We found that the EEG activities in monks shifted to a higher frequency from resting to meditation. Meditation starts with decrease of the (pre)frontal delta activity and increase of the (pre)frontal high beta and gamma activity; while at the deep meditative state, the posterior high-frequency activity was also increased, and could be specified as a biomarker for the deep meditation. The state increase of posterior high-frequency EEG activity was significantly correlated with the trait effects on heart rate and nueropilin-1 in monks, with the source of brain–heart correlation mainly locating in the attention and emotion networks. Our study revealed that the effects of Tibetan Buddhist meditation on brain, heart, and proteomics were highly correlated, demonstrating meditation as an integrative body–mind training.

Meditation is a progressive process in which meditators may experience different stages to finally reach a deep meditation state. However, the temporal-dynamic process of meditation remains unclear. In this study, we recruited 38 experienced Tibetan Buddhism meditators to explore the dynamic process from resting to deep meditation from the aspects of EEG oscillations and networks. We found that the delta power was reduced and the transitivity of the delta network was increased immediately after the start of meditation. Then, the beta and gamma power increased, and the clustering coefficient and global efficiency of the gamma network increased at the deep meditation substage. Our results suggested that the participants entered into a wakeful and non-judgmental state immediately after the start of meditation, and then achieved a more efficient information processing and transferring only at a deep meditation state. Our study showed that meditation was a time-varying process, deep meditation was a different substage dominated by high frequency EEG oscillations and more small-world like brain networks.

An accurate segmentation and quantification of the superficial foveal avascular zone (sFAZ) is important to facilitate the diagnosis and treatment of many retinal diseases, such as diabetic retinopathy and retinal vein occlusion. We proposed a method based on deep learning for the automatic segmentation and quantification of the sFAZ in optical coherence tomography angiography (OCTA) images with robustness to brightness and contrast (B/C) variations. A dataset of 405 OCTA images from 45 participants was acquired with Zeiss Cirrus HD-OCT 5000 and the ground truth (GT) was manually segmented subsequently. A deep learning network with an encoder–decoder architecture was created to classify each pixel into an sFAZ or non-sFAZ class. Subsequently, we applied largest-connected-region extraction and hole-filling to fine-tune the automatic segmentation results. A maximum mean dice similarity coefficient (DSC) of 0.976 ± 0.011 was obtained when the automatic segmentation results were compared against the GT. The correlation coefficient between the area calculated from the automatic segmentation results and that calculated from the GT was 0.997. In all nine parameter groups with various brightness/contrast, all the DSCs of the proposed method were higher than 0.96. The proposed method achieved better performance in the sFAZ segmentation and quantification compared to two previously reported methods. In conclusion, we proposed and successfully verified an automatic sFAZ segmentation and quantification method based on deep learning with robustness to B/C variations. For clinical applications, this is an important progress in creating an automated segmentation and quantification applicable to clinical analysis.

It has been reported that meditation is a progressive procedure to achieve a thoughtless and transcendental deep meditation state. However, it remains difficult to know whether and when the practitioner has achieved deep meditation state for lack of a reliable and objective measure. The aim of this study is to explore an electrophysiological biomarker for the deep meditation stage by studying the autonomic nervous system (ANS) activities during meditation using heart rate variability (HRV). We recruited 70 experienced Tibetan Buddhist monks, and recorded electrocardiogram signal for ~10 min of rest followed by ~30 min of meditation. We found two different stages of meditation, i.e., light meditation (0-10min) and deep meditation (after 10min) stages, which can be distinguished by the increased very low frequency (VLF, 0.003-0.04Hz) and low frequency (LF, 0.04-0.15Hz) power. The light meditation stage was comparable with the rest in the ANS activities, while the deep meditation stage was significantly different from the rest and light meditation stage. We speculate that the deep meditation stage could be marked by significant increases of VLF and LF. Meanwhile, ratio of low and high frequency power, standard deviation of RR intervals and fractal scaling exponents of detrended fluctuation analysis also increased in the deep meditation stage. Our results indicated that meditation is a dynamic process and the deep meditation was dominated by activated sympathetic nervous system.

An all-optical encoder based on a 3 × 3 crossed structure was assembled by stacking three polymer fibres. The encoding functions were predicated theoretically and demonstrated experimentally with very good agreement. The total insertion loss of the device is about 1 dB and the extinction ratio is larger than 10 dB. The output state can be controlled by launching optical signals to different input port, and the input state can be identified according to the output state. We believe that the all-optical compact encoder would be used in high-density PICs.

Tetrasulfonated aluminum phthalocyanine (AlS4Pc), a strongly red-emitting compound, shows high detection sensitivity, little effect of photobleaching, and photochemical stability, making it an excellent red-fluorescent probe. We have observed that in acid media, a low concentration of poly-L-lysine (PLL) has a strong fluorescence-quenching effect on AlS4Pc, forming the ion-pair complex as AlS4Pc-PLL with almost no fluorescence. However, in the presence of Bi3+, the fluorescence of AlS4Pc-PLL dramatically recovers and the emission is visual because of the remarkable recovery. Screening experiments with other metal ions reveal that only Bi3+ can restore the fluorescence of the AlS4Pc-PLL complex. The presence of other metal ions does not result in the recovery of fluorescence, indicating the high specificity of the response to Bi3+ of AlS4Pc-PLL. This is the key finding of the present study. It was also observed that the response to Bi3+ of AlS4Pc-PLL exhibits a linear relationship over a large concentration range (three orders of magnitude). Based on these findings, we have established a new quantitative analysis method for Bi3+ with high specificity and high sensitivity, using the ion-pair AlS4Pc-PLL complex as a red-fluorescent probe, and we discuss the reaction mechanism. The detection limit of this method is 0.0021 mg L−1. The linear relationship applies to the range of 0.007–34.9 mg L−1 with a correlation coefficient of 0.9993. The method established addresses the complex operation and time-consuming problems in traditional methods and is thus suitable for real applications. Satisfactory results have been obtained when the method was applied to the measurement of real samples. This study further expands the scope of new applications of phthalocyanine-based red-fluorescent probes in analytical sciences.

Despite accumulating evidence suggesting improvement in one's well-being as a result of meditation, little is known about if or how the brain and the periphery interact to produce these behavioral and mental changes. We hypothesize that meditation reflects changes in the neural representations of visceral activity, such as cardiac behavior, and investigated the integration of neural and visceral systems and the spontaneous whole brain spatiotemporal dynamics underlying traditional Tibetan Buddhist meditation. In a large cohort of long-term Tibetan Buddhist monk meditation practitioners, we found distinct transient modulations of the neural response to heartbeats in the default mode network (DMN), along with large-scale network reconfigurations in the gamma and theta bands of electroencephalography (EEG) activity induced by meditation. Additionally, temporal-frontal network connectivity in the EEG theta band was negatively correlated with the duration of meditation experience, and gamma oscillations were uniquely, directionally coupled to theta oscillations during meditation. Overall, these data suggest that the neural representation of cardiac activity in the DMN and large-scale spatiotemporal network integrations underlie the fundamental neural mechanism of meditation and further imply that meditation may utilize cortical plasticity, inducing both immediate and long-lasting changes in the intrinsic organization and activity of brain networks.

In acidic media, cationic phthalocyanine Alcian blue 8GX, has an efficient fluorescence quenching effect on anionic phthalocyanine tetrasulphoaluminium phthalocyanines (AlS4Pc), forming an almost non-fluorescent associate. Based on this discovery, a red-emitting fluorescent probe consisted of AlS4PC and Alcian blue 8GX has been developed through molecular assembly. Further studies indicated that the presence of Hg(II) ion has a significant fluorescence recovery effect of the probe. Notably, only Hg(II) can significantly restore the fluorescence of AlS4Pc-Alcian blue 8GX system which was revealed from the screening experiments of common metal ions, which confirmed that the fluorescence recovery by other metal ions is very weak or even unrestored, showing high specificity and sensitivity AlS4Pc-Alcian blue 8GX to Hg(II). Thus, a new fluorimetry for Hg(II) with high specificity and high sensitivity in a wide concentration range has been established using AlS4Pc-Alcian blue 8GX associate as a red-emitting fluorescent probe. It is more noteworthy that this study opens a new way for development and application of functional phthalocyanine based red-emitting fluorescent probes.

We have found that a positively charged cationic copper phthalocyanine, Alcian blue (Alcian blue 8GX), can efficiently quench the fluorescence of an oppositely charged red fluorescent phthalocyanine compound with a matched molecular structure, tetrasulfonated aluminum phthalocyanine (AlS4Pc), because of the formation of an ion pair complex (AlS4Pc-Alcian blue 8GX) that exhibits almost no fluorescence. An investigation was carried out on the fluorescence recovery of AlS4Pc-Alcian blue 8GX caused by a series of anionic surfactants containing a sulfonic group (sodium dodecylbenzenesulfonate (SDBS), sodium lauryl sulfate (SLS), and sodium dodecyl sulfate (SDS)). The results showed that SDBS exhibited a significant response, and the highest sensitivity among the surfactants. Due to its high efficiency of fluorescence quenching and the high level of fluorescence recovery, direct observes can even be performed by the naked eye. The results revealed that the Alcian blue 8GX-AlS4Pc ion-pair complex fluorescent probe only responded to SDBS in the low-concentration range. Based on the new founding, this study proposed a novel principle and method of fluorescence enhancement to specifically measure the concentration of SDBS, thereby achieving a highly sensitive and highly specific determination of SDBS. Under the optimal conditions, the fluorescence intensity (I(f)) of the system and the concentration of SDBS in the range of 1 × 10(-7) - 1 × 10(-5) mol/dm(3) exhibited a good linear relationship. This method is highly sensitive, and the operation is simple and rapid. It had been applied for the quantitative analysis of SDBS in environmental water, while achieving satisfactory results compared with those of the standard method. This study developed a new application of the fluorescent phthalocyanine compounds used as molecular probes in analytical sciences.

The conventional spectrophotometric method that is often applied to determine ribonuclease (RNase) has disadvantages that include cumbersome manipulation, time-consuming processing and a lack of linear range. We had found that a low concentration of RNA could induce cationic aluminum phthalocyanine (tetra(trimethylammonio)aluminum phthalocyanine (TTMAAlPc)), which emitted strong red fluorescence to aggregate in neutral media, resulting in an almost complete quenching of fluorescence from the cationic aluminum phthalocyanine. The RNA is degraded through hydrolysis by RNase, which destroys the induced aggregation of TTMAAlPc on RNA and releases free TTMAAlPc, leading to a significant fluorescence recovery of the reaction system. Based on this new finding, a method to detect RNase by enhanced fluorescence was established using the TTMAAlPc-RNA association complex as a new fluorogenic substrate of RNase. The optimal conditions were determined, and the interfering foreign substances were investigated. Under optimal conditions, the linear range was 0.05 - 50 μg/L, and the detection limit was 0.02 μg/L. This method was applied for the analysis of ribonuclease in urine specimens from normal adults, and the results were consistent with those determined by conventional spectrophotometric methods. The developed method is easy to operate and highly sensitive, and has a wide linear range, thus solving issues with conventional methods. This study applied, for the first time, cationic phthalocyanine as a fluorescent probe in the detection of nuclease, which provides new applications of phthalocyanine as a fluorescent probe emitting at the red wavelength region.

Two simple structures, a star topology network and a tree topology network, were assembled for arbitrary and vertical optical coupler applications using flexible polymer micro/nanowires, which were fabricated by a direct drawing technique from polymer solution. Experimental demonstration shows that the loss of the wires is less than 0.11 dB/mm at 650 nm wavelength. The insertion loss of the two simple structures, which were assembled by intersecting two wires, is 0.6–0.86 dB. The insertion losses of the star topology network and the tree topology network, which was assembled by knotting three wires, are 1.14 and 1.31 dB, respectively.