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Arousal and awareness are two components of consciousness whose neural mechanisms remain unclear. Spontaneous peaks of global (brain-wide) blood-oxygenation-level-dependent (BOLD) signal have been found to be sensitive to changes in arousal. By contrasting BOLD signals at different arousal levels, we find decreased activation of the ventral posterolateral nucleus (VPL) during transient peaks in the global signal in low arousal and awareness states (non-rapid eye movement sleep and anesthesia) compared to wakefulness and in eyes-closed compared to eyes-open conditions in healthy awake individuals. Intriguingly, VPL-global co-activation remains high in patients with unresponsive wakefulness syndrome (UWS), who exhibit high arousal without awareness, while it reduces in rapid eye movement sleep, a state characterized by low arousal but high awareness. Furthermore, lower co-activation is found in individuals during N3 sleep compared to patients with UWS. These results demonstrate that co-activation of VPL and global activity is critical to arousal but not to awareness. [Display omitted] • Co-activation of VPL and global brain is elevated in wakefulness and unresponsive wakefulness • VPL activity is reduced in low arousal states compared to global brain activity • Co-activation of VPL and global transient signal is related to arousal rather than awareness • VPL might attain co-activation with global cortex via sensory-motor areas to modulate arousal Han et al. employed multi-center fMRI data to dissociate the components of consciousness, arousal, and awareness. By comparing co-activation of spontaneous global brain signal across conditions, they demonstrate that transient co-activation of the ventral posterolateral nucleus and global signal is predominantly associated with arousal rather than awareness. [ABSTRACT FROM AUTHOR]

• An analytical model for ENF mode II fracture analysis was developed. • Bi-linear cohesive parameters of the composite can be determined through the model. • The model allows to determine G IIc with no need of data reduction. • R-curve can be analytically obtained. The complicated toughening mechanism of Mode II cracking in end notch flexure (ENF) test for fibrous composites prevents the existence of clear crack-tip. Hence the concept of equivalent linear crack length was proposed to avoid detecting the crack-tip in ENF test, which assumes that the increase of compliance due to the development of fracture process zone (FPZ) or crack propagation is attributed to the equivalent elastic crack length giving the same compliance as the one of the actual crack with its FPZ; thus the equivalent crack length can be estimated according to the associated compliance obtained from experiment. The objective of the presented work was to develop an analytical model for the analysis of ENF test specimen without need for crack-tip identification and complicated data reduction. Bilinear cohesive law was employed to model the cohesive force across the potential crack interfaces. Analytical solutions for the governing equation were derived. Furthermore, methods to determine the cohesive parameters, the length of fracture process zone (FPZ), and the energy release rate were developed. The critical loads corresponding to the damage and crack onset can also be estimated by the model. Experimental validation was implemented and a good agreement was achieved between the test results and model predictions. It can be concluded that bilinear cohesive law may achieve a good approximation for the tangential traction-separation constitutive relationship in Mode II fracture; the shear strength of the material can be taken as the critical stress of cracking onset; the energy release rate depends on the initial crack length to some extent, and this effect could be reduced as the length of initial crack increases. [ABSTRACT FROM AUTHOR]

• A model for analyzing rolling shear stress for out-of-plane bending CLT panels was developed. • Formula for calculating shear capacity of CLT bending member was derived. • The proposed model is easier for calculating than current model but retain its accuracy. When used as horizontal components to carry vertical loads, such as floors and beams, the design of cross-laminated timber (CLT) panels is driven by out-of-plane bending. In this case, rolling shear is always one of the major concerns that governs the performances of ultimate limit state of CLT members. Analytical models are available for predicting the shear capacity of CLT panels, but they are computational extensive and cannot provide the longitudinal distribution of shear stress which is necessary to predict where the failure will happen. In this paper, a layered beam-based analytical model, for analyzing the stress of rolling shear for transversely loaded CLT members was developed. The model deems that the shear deformations of out-of-plane bending CLT members are carried by cross layers while the deformations of bending moment are carried by parallel layers. Based on the layered beam theory, the equation that governs the stress of rolling shear and its analytical solution were derived. It was found that the shear stress distribution in CLT longitudinal direction obeys exponential law and the maximum shear stress is located at the end of the CLT member. Formulas to predict the shear capacity for 3- and 5-layer CLT panels under out-of-plane bending were obtained. The proposed method was validated by the experimental data generated by the authors and by other researchers. Comparing to the shear analogy method and Gamma method, the proposed method requires less computational work and provides similar accuracy. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effects of 55% ethanol extracts from G. lucidum (GL55) on high-fat diet (HFD) induced hyperlipidaemia and gut microbiota modulation in rats. UPLC-QTOF MS-MS indicated that GL55 was enriched with triterpenoids. GL55 markedly alleviated the dyslipidemia in HFD fed rats through decreasing the levels of serum total triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), alanine transaminase (ALT), free fatty acids (FFA), fasting blood-glucose (FBG) and inhibiting hepatic steatosis. Furthermore, high throughput sequencing analysis revealed that GL55 supplementation altered the composition of gut microbiota, in particular increased the relative abundance of functionally relevant enterotypes, such as Alloprevotella , Ruminococcus and Prevotella , but decreased the proportion of Turicibacter and Clostridium XVIII compared with the HFD group. The Spearman's correlation analysis revealed that Alloprevotella , Ruminococcus and Prevotella were negatively correlated with serum lipid profiles. Meanwhile, GL55 treatment regulated mRNA and protein expressions levels involved in lipid and glucose metabolism. [ABSTRACT FROM AUTHOR]

Aims This study aimed to investigate potential candidates and molecular mechanisms of myocardial ischemia/reperfusion (I/R) injury (MIRI) in type 2 diabetes mellitus. Main methods Type 2 diabetic and myocardial I/R mouse models were established with a high fat-diet (HFD) for 24 weeks and subjecting to global ischemia/reperfusion for 1 h/3 h, respectively. Microarray analysis was applied to screen differentially expressed genes (DEGs) in the hearts of these mice. Moreover, H9c2 cells were treated with high glucose (HG) and/or hypoxia and reoxygenation (H/R). Subsequently, the expression of suppressor of cytokine signaling 2 (SOCS2) was knocked down by siRNA followed by the above treatments. Then, the cell lipid peroxidation and apoptosis-related indicators (malondialdehyde, MDA, and lactate dehydrogenase, LDH, cleaved-caspase-3; glucose-regulated protein 78, GRP78;), Janus kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway-related proteins (p-JAK2 and p-STAT5b) and insulin-like growth factor-1 (IGF-1) were detected. Key findings The mRNA levels of selected DEGs, such as Angptl4 , Gadd45b , Rnf122 and SOCS2 , showed a high degree of correlation with the microarray data. In addition, the levels of SOCS2, caspase-3, GRP78, LDH and MDA were increased, while the IGF-1 level was down-regulated in cells treated with HG and/or H/R compared to untreated cells ( p < 0.05). However, SOCS2 knockdown elevated the expression levels of IGF-1, p-JAK2 and p-STAT5b, as well as caspase-3, GRP78, LDH and MDA. Significance This research suggests that overexpressed SOCS2 might exacerbates MIRI in type 2 diabetes mellitus by inhibiting the expression of IGF-1 via the JAK-STAT signaling pathway. [ABSTRACT FROM AUTHOR]

Time and space are the basic building blocks of nature. As a unique existent in nature, our brain exists in time and takes up space. The brain’s activity itself also constitutes and spreads in its own (intrinsic) time and space that is crucial for consciousness. Consciousness is a complex phenomenon including different dimensions: level/state, content/form, phenomenal aspects, and cognitive features. We propose a Temporo-spatial Theory of Consciousness (TTC) focusing primarily on the temporal and spatial features of the brain activity. We postulate four different neuronal mechanisms accounting for the different dimensions of consciousness: (i) “temporo-spatial nestedness” of the spontaneous activity accounts for the level/state of consciousness as neural predisposition of consciousness (NPC); (ii) “temporo-spatial alignment” of the pre-stimulus activity accounts for the content/form of consciousness as neural prerequisite of consciousness (preNCC); (iii) “temporo-spatial expansion” of early stimulus-induced activity accounts for phenomenal consciousness as neural correlates of consciousness (NCC); (iv) “temporo-spatial globalization” of late stimulus-induced activity accounts for the cognitive features of consciousness as neural consequence of consciousness (NCCcon). [ABSTRACT FROM AUTHOR]

[Display omitted] • CFF reduces fat accumulation within hepatocytes. • CFF can mediate gut microbiota to regulate disorders of glucose metabolism. • CFF can regulate blood glucose levels through PI3K / AKT / GLUT4, AMPK-α signaling pathways. This study was aimed at investigating the hypoglycemic effect of Chlorella pyrenoidosa functional formulations (CFF), composed of extracts of C. pyrenoudosa , Ganoderma lucidum , and Panax ginseng with chromium-enriched yeast, on streptozotocin (STZ)-induced high-glucose and high-fat diet-fed mice. In this study, CFF significantly reduced the symptoms of weight loss, liver deformation, cecum injury, and jejunal inflammation in type 2 diabetic mice. In addition to enriching gut probiotics, CFF inhibited harmful microorganisms that could affect glycolipid metabolism disorders (GLD) and enhanced production of short-chain fatty acids. In conclusion, CFF may be able to alleviate GLD symptoms. The study suggests that CFF regulates GLD and the possible mechanisms for this regulation. This provides a theoretical basis for developing nutritious and healthy foods. [ABSTRACT FROM AUTHOR]

• Combined out-of-plane bending and compression is an inevitable loading condition for CLT walls. • The experimental program consisted of 36 CLT panel specimens. • The damage was caused by the local buckling near the mid-height of the outer layer on the compression side. • Signs of shear failure of cross layers were evident almost simultaneously with the outer layer failure. • The interaction equations specified in the Canadian design standard are appropriate for the CLT panels under small load eccentricities. Combined out-of-plane bending and compression is an inevitable loading condition for cross-laminated timber (CLT) walls due to the out of plumbness, initial panel curvature and load eccentricity. Because of the weaker cross layers, the mechanical performance and failure mode of the CLT panels under such loading significantly differ from those of the other wood members, such as sawn timber and glulam. This experimental study focuses on investigating the behavior of CLT panels under the stated loading scenario. The experimental program consisted of 36 specimens, including 12 five-layer CLT panels provided by two Canadian manufacturers, as well as 12 three-layer and 12 five-layer CLT panels provided by a Chinese manufacturer. All the specimens were tested in Canada and China, respectively, using the same test setup. It was found that in the majority of the specimens, the damage was caused by the local buckling near the mid-height of the outer layer on the concave compression side at about 45%–60% of the ultimate failure load and 25%–35% of the ultimate deflection. The dominant failure mode was characterized as the crushing yield of the outer layer on the concave side (fibers in compression) near the mid-height after the local buckling progressed. Signs of shear failure of cross layers were evident almost simultaneously with the outer layer failure. Hence, although the dominant failure mode was likely triggered by the fracture in the cross layers due to rolling shear, the load-carrying capacity of the CLT panels under the combined out-of-plane bending and compression is governed by the compression failure of the longitudinal outer layers. It was found that a cross-layered panel can maintain its integrity before failure. It was also noted that the interaction equations specified in the Canadian design standard are appropriate for the CLT panels under small load eccentricity, while for panels that have large load eccentricity, the appropriateness of the interaction equation is questionable. Based on the test results obtained, the validity of the interaction equation for the prediction of the load-carrying capacity of CLT columns, specified in the CSA O86-19, is confirmed for cases in which P f / P r > 0.5 and M f / M r < 0.3. For the cases of P f / P r < 0.5 and M f / M r > 0.3 , modification of the equation is needed. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated an overlap between the neural substrate of resting-state activity and self-related processing in the cortical midline structures (CMS). However, the neural and psychological mechanisms mediating this so-called “rest-self overlap” remain unclear. To investigate the neural mechanisms, we estimated the temporal structure of spontaneous/resting-state activity, e.g. its long-range temporal correlations or self-affinity across time as indexed by the power-law exponent (PLE). The PLE was obtained in resting-state activity in the medial prefrontal cortex (MPFC) and the posterior cingulate cortex (PCC) in 47 healthy subjects by functional magnetic resonance imaging (fMRI). We performed correlation analyses of the PLE and Revised Self-Consciousness Scale (SCSR) scores, which enabled us to access different dimensions of self-consciousness and specified rest-self overlap in a psychological regard. The PLE in the MPFC's resting-state activity correlated with private self-consciousness scores from the SCSR. Conversely, we found no correlation between the PLE and the other subscales of the SCSR (public, social) or between other resting-state measures, including functional connectivity, and the SCSR subscales. This is the first evidence for the association between the scale-free dynamics of resting-state activity in the CMS and the private dimension of self-consciousness. This finding implies the relationship of especially the private dimension of self with the temporal structure of resting-state activity. [ABSTRACT FROM AUTHOR]

• A model to predict the load-carrying capacity of CLT bending-compression members were developed. • Cross layer can maintain its joint efficiency until failure. • Maximum stress of rolling shear appears at the end of beam-column. • The compression failure-based model provides good prediction of load-carrying capacity of CLT beam-columns. Rolling shear is one of the major concerns that significantly impact the performance of CLT walls if they are subjected to combined out-of-plane bending and compression loads. Because the effects of rolling shear and out-of-plane bending are coupled to each other, prediction of the load-carrying capacity of CLT wall is always a challenge for the design of CLT structures. Current design codes employ an Ayrton-Perry type interaction equation as the failure criterion to check the safety of a CLT panel loaded with combined bending and compression. Nevertheless, there is no model available to predict their load-carrying capacity. The presented work aims at developing an analytical model to predict the load-carrying capacity of CLT wall loaded with combined out-of-plane bending and compression. In total 12 five-layer CLT panels loaded with different initial load eccentricities were tested to investigate the failure modes. Observed during the test were two ultimate failure modes, i.e., compression crush on the concave side and tension rupture in convex side. Based on these failure modes and deeming the test member as a beam-column, an analytical model which takes rolling shear effects into account to predict the load-carry capacity of CLT compression-bending members was developed. An explicit formula based on compression failure mode was proposed. The model is capable of determining the distribution of rolling shear stress along longitudinal direction, rolling shear-induced axial force and moments in CLT beam-columns. By calculating the load-carrying capacities of the specimens tested in this study as well as the additional three- and seven-layer specimens tested by another studies, it was found that the compression failure mode-based formula can provide good agreements with the test results. [ABSTRACT FROM AUTHOR]

Conscious access to sensory information is likely gated at an intermediate site between primary sensory and transmodal association cortices, but the structure responsible remains unknown. We perform functional neuroimaging to determine the neural correlates of conscious access using a volitional mental imagery task, a report paradigm not confounded by motor behavior. Titrating propofol to loss of behavioral responsiveness in healthy volunteers creates dysfunction of the anterior insular cortex (AIC) in association with an impairment of dynamic transitions of default-mode and dorsal attention networks. Candidate subcortical regions mediating sensory gating or arousal (thalamus, basal forebrain) fail to show this association. The gating role of the AIC is consistent with findings in awake participants, whose conscious access is predicted by pre-stimulus AIC activity near perceptual threshold. These data support the hypothesis that AIC, situated at an intermediate position of the cortical hierarchy, regulates brain network transitions that gate conscious access. [Display omitted] • Dysfunction of anterior insula during anesthesia disables brain network transitions • Prestimulus activity of anterior insula predicts conscious access of visual stimuli • Anterior insula might be a gate for conscious access of sensory information • This cortical gate occupies an intermediate position along a neurocognitive hierarchy In a human neuroimaging study, Huang et al. manipulate the level and content of consciousness using independent experimental protocols to demonstrate that the anterior insula, situated between unimodal and transmodal cortical areas along the brain's functional hierarchy, serves as a gate for conscious access of sensory information. [ABSTRACT FROM AUTHOR]

Achieving ultra-high thermal conductivity while maintaining the electrical insulation of polymers is highly desirable for many applications such as thermal management and packaging. In this work, polyethylene/boron nitride nanoplatelets (PE/BNNP) nanocomposite film was produced through melt processing followed by uniaxial stretching. Microstructural analysis reveals that the stretched composite film features a co-continuous network structure which consists of oriented lamellae bridged by both stretched polymer chains and aligned BNNPs along the stretching direction. The resulting film exhibit a metal-like thermal conductivity as high as 106 W m−1 K−1 and it is believed that the unique network structure has enabled efficient phonon transfer across the film, resulting in superior thermal transporting performance. This work shines a light on the design and scalable manufacturing of high performance functional polymer-based composites for future thermal management applications. [ABSTRACT FROM AUTHOR]

• Fabricated a grinding tool for coronary calcified tissue removal. • Analyzed the force, temperature and debris morphology during the grinding process. • Illustrated the influence of tool parameters and grinding parameters on grinding results. Coronary rotational atherectomy (CRA) means of use a tiny grinding tool to rotate at high speed in the blood vessels, so as to remove calcified tissue, effectively enlarge the inner diameter of the vessels, which is an important tool for the treatment of cardiovascular calcified blockage. However, excessive grinding force, temperature and debris size can lead to serious surgical complications and endanger the patient life during CRA. This study introduces the design, fabrication and performance verification process of a novel grinding tool, and investigates the influence of tool geometrical parameters and grinding parameters The experimental results showed that: the novel grinding tool can effectively remove the simulated calcified tissue by grinding. The geometrical size of tools plays an important effect on the grinding properties, which can result in increasing grinding force, temperature and debris size with the increase of tool diameters. In addition, with the increase of rotational speed, the grinding force and temperature increase gradually, while the debris size decreases as the rotational speed increases. The increasing inner diameter of bone can also lead to a decrease in grinding force and temperature slightly. All the obtained results can give effective guidance for clinical operations. [ABSTRACT FROM AUTHOR]

Neural activity varies continually from moment to moment. Such temporal variability (TV) has been highlighted as a functionally specific brain property playing a fundamental role in cognition. We sought to investigate the mechanisms involved in TV changes between two basic behavioral states, namely having the eyes open (EO) or eyes closed (EC) in vivo in humans. To these ends we acquired BOLD fMRI, ASL, and [ 18 F]-fluoro-deoxyglucose PET in a group of healthy participants ( n  = 15), along with BOLD fMRI and [ 18 F]-flumazenil PET in a separate group ( n  = 19). Focusing on an EO- vs EC-sensitive region in the occipital cortex (identified in an independent sample), we show that TV is constrained in the EO condition compared to EC. This reduction is correlated with an increase in energy consumption and with regional GABA A receptor density. This suggests that the modulation of TV by behavioral state involves an increase in overall neural activity that is related to an increased effect from GABAergic inhibition in addition to any excitatory changes. These findings contribute to our understanding of the mechanisms underlying activity variability in the human brain and its control. [ABSTRACT FROM AUTHOR]