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While brain function is supported and constrained by the underlying structure, the connectome-based link estimated by current approaches is either relatively moderate or accompanied by high model complexity, with the essential principles underlying structure-function coupling remaining elusive. Here, by proposing a mapping method based on network eigendecomposition, we present a concise and strong correspondence between structure and function. We show that the explanation of functional connectivity can be significantly improved by incorporating interactions between different structural eigenmodes. We also demonstrate the pronounced advantage of the present mapping in capturing individual-specific information with simple implementation. Applying our methodology to the human lifespan, we find that functional diversity decreases with age, with functional interactions increasingly dominated by the leading functional mode. We also find that structure-function liberality weakens with age, which is driven by the decreases in functional components that are less constrained by anatomy, while the magnitude of structure-aligned components is preserved. Overall, our work enhances the understanding of structure-function coupling from a collective, connectome-oriented perspective and promotes a more refined identification of functional portions relevant to human aging, holding great potential for mechanistic insights into individual differences associated with cognition, development, and neurological disorders. An eigenmode-based structural and functional connectivity mapping approach applied to diffusion and functional MRI data reveals decreased structure-function liberality with age across the human lifespan. [ABSTRACT FROM AUTHOR]

While the link between brain structure and function remains an ongoing challenge, the prevailing hypothesis is that the structure-function relationship may itself be gradually decoupling from unimodal to transmodal cortex. However, this hypothesis is constrained by the underlying models which may neglect requisite information. Here we relate structural and functional connectivity derived from diffusion and functional MRI through orthogonal eigenmodes governing frequency-specific diffusion patterns. We find that low-frequency eigenmodes contribute little to functional interactions in transmodal cortex, resulting in divergent structure-function relationships. Conversely, high-frequency eigenmodes predominantly support neuronal coactivation patterns in these areas, inducing structure-function convergence along a unimodal-transmodal hierarchy. High-frequency information, although weak and scattered, could enhance the structure-function tethering, especially in transmodal association cortices. Our findings suggest that the structure-function decoupling may not be an intrinsic property of brain organization, but can be narrowed through multiplexed and regionally specialized spatiotemporal propagation regimes. Brain structure and function have been observed to be increasingly untethered in transmodal cortex. Here, the authors show that structure-function coupling in these areas can be enhanced by diffusion patterns governed by high-frequency eigenmodes. [ABSTRACT FROM AUTHOR]

Nanosized titanium dioxide (nano-TiO2) has been widely used in consumer products. It can cross the blood-testis barrier (BTB), and it has adverse effects on the male reproductive system. However, the specific mechanism has not been fully elucidated. The purpose of this study was to understand the role of the JNK signaling pathway in the apoptosis and abnormal expression of BTB junction proteins induced by nano-TiO2 in TM4 cells. After different concentration of nano-TiO2 treatments, the cell viability, apoptosis, mitochondrial membrane potential (Δψm), BTB junction proteins (Claudin-11, ZO-1, β-catenin), apoptosis-related proteins (Bax, Bcl-2, cleaved caspase-9, cleaved caspase-3), and phosphorylated (p)-JNK protein were examined. The results showed that cell viability, apoptosis rates, Δψm, and apoptosis-related protein levels changed in a concentration-dependent manner. Cell viability decreased significantly from 100 μg/mL nano-TiO2 group. Apoptosis rates increased significantly from 150 μg/mL nano-TiO2 group, and Δψm decreased significantly from 150 μg/mL nano-TiO2 group. The protein levels of Bax, cleaved caspase-9, and cleaved caspase-3 increased significantly from 150 μg/mL nano-TiO2 group, and the protein level of Bcl-2 decreased significantly from 100 μg/mL nano-TiO2 group. The protein level of p-JNK increased significantly from 100 μg/mL nano-TiO2 group. Abnormal expression of ZO-1 and β-catenin started from 150 μg/mL nano-TiO2 group, and abnormal expression of Claudin-11 started from 100 μg/mL nano-TiO2 group. Cells were treated with JNK inhibitor SP100625 to determine whether the changes of the above indicators in the concentration of 150 μg/mL nano-TiO2 group can be reversed. We found that SP100625 at 20 μM significantly reversed these effects. These results highlighted that nano-TiO2 could activate the JNK signaling pathway to induce mitochondria-mediated apoptosis and abnormal expression of BTB junction proteins in TM4 cells. [ABSTRACT FROM AUTHOR]

In mountainous basins with low anthropogenic influences, runoff generation varies geographically, and it is essential to investigate the hierarchical controls of geographical features on hydrological responses. In this study, a stepwise clustering scheme was proposed to classify 64 mountainous basins located in eastern China into 11 basin groups and 3 hierarchies according to the geographical features of rainfall, topography and geomorphology, and soil and geology. Then, the leave-one cross validation assessing the transferability of hydrological model parameters was used to measure the hydrological similarity among basins and within each group, and to examine the quality of classification. The results showed that 92% of all basins had other basins with high similarity. The overall similarity of the hydrological responses in the 11 basin groups was quite different. The basin groups driven by heavy rainfall events tended to form highly similar runoff processes. Basins in the groups with steeper terrain, more convergent slopes, rounder shapes, and better vegetation cover also exhibited a higher overall hydrological similarity. Then, according to the discharge characteristics, the controlling role and intensity of different hierarchical geographical features on hydrological responses were quantitatively represented. In 6 of the 11 basin groups, rainfall features (e.g. average monthly rainfall and rainstorm characteristics) were collectively the primary controlling factor of runoff, while topographic and geomorphic features were the second most important factor. Rainfall features were the second most important controlling factor in the other four basin groups. However, the controlling role of soil and geological features on hydrological responses appeared to be unstable. In summary, these findings could provide guidance for hydrological predictions in ungauged basins in diverse geographical environments. [ABSTRACT FROM AUTHOR]

Inositol phosphate synthase (IPS) is a rate-limiting enzyme in myo-inositol biosynthesis, which can regulate stress responses in plants and animals. However, there are few studies on the function of IPS in insects, especially in Apis cerana cerana. In this study, the inositol-3-phosphate synthase 1-B gene (AccIPS1-B) was isolated from Apis cerana cerana, and its connection to antioxidant defence was investigated. The open reading frame of AccIPS1-B was 1542 bp, encoding a 513 amino acid polypeptide. Quantitative real-time PCR analysis revealed that the expression level of AccIPS1-B was highest in pupae of Apis cerana cerana, and it was expressed at higher levels in the thorax than in other tissues tested. Moreover, the expression of AccIPS1-B was significantly upregulated by abiotic stresses. The recombinant AccIPS1-B also displayed significant tolerance to cumene hydroperoxide and HgCl2. In addition, knockdown of AccIPS1-B significantly suppressed the expression of most of the antioxidant genes and decreased the antioxidant enzymatic activities of SOD, POD, and GST. Taken together, these findings indicate that AccIPS1-B may be involved in the response to antioxidant defence and development in Apis cerana cerana. [ABSTRACT FROM AUTHOR]