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Nod-like receptor protein 3 (NLRP3) inflammasome, autophagy, and the aggregation of β-amyloid (Aβ) are key factors in Alzheimer's disease (AD) development. Ghrelin has shown promise in providing neuroprotection for AD. However, the mechanism underlying ghrelin's ability to improve AD by modulating autophagy and the NLRP3 inflammasome requires further clarification. Primary hippocampus neurons and mice were stimulated with Aβ1-42 to create an in vitro and in vivo AD model, followed by ghrelin administration for intervention. Additionally, we subjected the cells to 3-methyladenine (3-MA) treatment. Neuron morphology, microtubule-associated protein 2 (MAP-2) expression, apoptosis, cytokine levels, and protein expression were measured using various techniques. The escape latency of mice was assessed using the Morris water maze (MWM) test, and histopathology of the hippocampus was determined using hematoxylin–eosin staining. At 1–100 nM, ghrelin increased neuron/synapse numbers and MAP-2 expression dose-dependently while blocking apoptosis in Aβ1-42-treated cells. Moreover, ghrelin reduced the expression of Aβ1-42, p-Tau/Tau, p62, NLRP3, ASC, and cleaved Caspase-1, while increasing the expression of LC3II/LC3I and Beclin1 in AD cells. Furthermore, ghrelin treatment also decreased the levels of Aβ1-42, IL-1β, and IL-18 in the cells. The effects of ghrelin were reversed by 3-MA. Our in vivo experiments provided further confirmation of the above effect of ghrelin on AD. Additionally, the injection of Aβ1-42 induced increased escape latency in mice and histopathological changes in hippocampal neurons. All of these abnormalities were significantly improved following administration of ghrelin. Ghrelin mitigated Aβ1-42-induced neurotoxicity and relieved neuronal damage by upregulating autophagy to inactivate NLRP3, thus showing promising potential in treating AD. [ABSTRACT FROM AUTHOR]

In this paper, for the extended lattice Gelfand–Dickey hierarchy, we construct its n-fold Darboux transformation and additional flows. And we prove that these flows are actually symmetries of the extended lattice Gelfand–Dickey hierarchy. Further, we show how the additional flows act on the tau function. On this basis, we generalize the extended lattice Gelfand–Dickey hierarchy to the multicomponent and noncommutative versions, and give the Lax equations, Sato equations, zero-curvature equations and other equivalent expressions of these versions. Moreover, we investigate their Darboux transformations and additional symmetries. [ABSTRACT FROM AUTHOR]

Designated as a world heritage site by UNESCO in 1987, the Mogao Grottoes is famous for its cultural relics, in particular, the superb murals and painted sculptures. Moisture has been confirmed as the most active factor that could result in mural diseases. Therefore, ascertaining the moisture distribution of the cliff is of great significance for preventing the deterioration of murals and painted sculptures. In this study, a multi-electrode resistivity survey is applied atop the cliff of Mogao Grottoes. By deploying survey lines in two main study areas, the moisture distribution of the cliff is reflected by the resistivity profiles qualitatively. The results show that there is a mutually verifying relationship between the resistivity profiles and the water content of the exploratory well. In general, the resistivity of the cliff body is low in the distribution range of 1–300 Ω·m. It shows that the moisture content of these gullies atop the cliff is even lower. Besides, four potential danger areas are determined on the cliff face. Murals in these caves, which are excavated in these areas, will suffer more serious deterioration due to the moisture migration. The result also ascertains that the resistivity of the cliff could determine the moisture distribution inside the cliff. Moreover, this study can provide a firm scientific basis for protecting the valuable murals and painted sculptures in the caves. [ABSTRACT FROM AUTHOR]

This work reports the synthesis of Zinc porphyrin-based porous (POP-ZnTPP) by a typical Yamamoto-Ullmann coupling reaction, which exhibited abundant tiny nanopores, excellent CO2 adsorption capacity, and CO2/N2 selectivity. The open pore environment of POP-ZnTPP facilitated the exposure of active sites, which intensified the catalytic activity in the cycloaddition reaction of epoxides (PO) with CO2 under mild conditions. As expected, POP-ZnTPP catalyst completely converted PO to cyclic carbonates (COCs) at ambient temperature (25 °C, 1.5 MPa). It is also worth noting that POP-ZnTPP could convert PO into COCs under the simulated flue gas (15% CO2 and 85% N2, v/v) atmosphere, which is very favorable for industrial applications of CO2. In addition, POP-ZnTPP catalyst as one of the most outstanding catalysts exhibited excellent broad substrate scope and remarkable reusability. This work has a certain guiding significance for developing an environmentally friendly COC production process. [ABSTRACT FROM AUTHOR]

Apocynum venetum is a traditional and popular Chinese herb used for medicine and tea, and its major bioactive components is flavonoid. This study aimed to analyze the flavonoid production and antioxidative activity of the hairy roots under 250 mL shake flask and 3 L bubble bioreactor cultivation. Agrobacterium rhizogenes strain Ar.1193 was used to induce hairy roots at the wounding site of Apocynum venetum stems, and a 69.17% genetic transformation rate was noted. Hairy roots with the most vigorous growth were selected to analyze growth and flavonoid production over one complete growth cycle (30 d). The dry weight of the roots increased tenfold, flavonoid contents peaked at 25 d under shake flask and bioreactor cultivation, and the flavonoid content of roots in the bioreactor was 43.97% higher than that of roots in the shake flask. The flavonoid content and antioxidative activity of liquid-cultured hairy roots were significantly higher than those of field-planted roots, tissue-cultured plant roots, and callus. Moreover, a total of 117 flavonoids were detected in hairy roots. The results of the present study highlight hairy roots of Apocynum venetum could serve as an alternative to whole plants and may be used for the large-scale production of flavonoid. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) is common in East Asia, yet its molecular and pathogenic mechanisms remain unclear. Circular RNAs (circRNAs) are differentially expressed in GC and may be promising biomarkers. Here, we investigated the role and regulatory mechanism of circTMC5 in GC. Methods: CircTMC5 expression was detected in human GC and adjacent tissues using microarray assays and qRT-PCR, while the clinicopathological characteristics of patients with GC were used to assess its diagnostic and prognostic value. The circTMC5/miR-361-3p/RABL6 axis was examined in vitro and vivo, and the immune roles of RABL6 were evaluated using bioinformatics analyses and immunohistochemistry (IHC). Results: CircTMC5 was highly expressed in GC tissues, plasma, and cell lines, and was closely related to histological grade, pathological stage, and T classification in patients with GC. CircTMC5 expression was also an independent prognostic factor for GC and its combined detection with carcinoembryonic antigen may improve GC diagnosis. Low circTMC5 expression correlated with good prognosis, inhibited GC cell proliferation, and promoted apoptosis. Mechanistically, circTMC5 overexpression promoted GC cell proliferation, invasion, and metastasis but inhibited apoptosis by sponging miR-361-3p and up-regulating RABL6 in vitro and vivo, whereas miR-361-3p up-regulation had the opposite effects. RABL6 was highly expressed in GC and was involved in immune regulation and infiltration in GC. Conclusions: CircTMC5 promotes GC and sponges miR-361-3p to up-regulate RABL6 expression, thus may have diagnostic and prognostic value in GC. RABL6 also displays therapeutic promise due to its role in the immune regulation of GC. [ABSTRACT FROM AUTHOR]

Recently, the sequential recommendation has become a hot spot. Previous works combined user long-term and short-term behavior to achieve the next item recommendation, but the previous works typically processed the user long-term sequential behavior in left-to-right order and some useful information may be overlooked in such a particular way. Moreover, these methods ignored that every user has his/her own attention on the different items. In this paper, we propose a novel hybrid model called Attentive Hybrid Recurrent Neural Networks to resolve these problems. The first module is the bidirectional long- and short-term memory network (Bi-LSTM), and the second is the GRU module, both of which are equipped with user-based attention mechanism. The hybrid model aims to grasp the user general preference as well as to capture the user latest intent. Experiment results on two public datasets suggest that our hybrid model has better performance on the next item recommendation task compared with previously reported baseline algorithm. [ABSTRACT FROM AUTHOR]

The power output characteristics of the hydro turbine is one of the core contents for transient calculation of the hydro turbine generating sets. In particular, the hydro turbine operates far beyond the given parameters region during the load rejection transient. As such, obtaining the complete characteristics of the hydro turbine becomes one of the key issues in calculating the transient process. In this study, methods for calculating the energy losses are proposed by analyzing the general characteristics of the inner energy losses within the hydro turbine. Characteristic parameters in the hydro turbine power model are calculated from the synthetical characteristics of the model hydro turbine. The transient power model of the hydro turbine has been established and applied to calculate and reconstruct the complete characteristics of the hydro turbine. Furthermore, the relationship curve between the mechanical friction loss power and the rotation speed under different head can be established by combing the runaway curve with the proposed turbine power model. This relationship is applied to construct the complete characteristics of the mechanical friction loss. Combining the proposed two complete characteristics, the power model of the hydro turbine is suitable for simulation with a wide range of fluctuations as well as the load rejection transient. Details of the computational procedures are presented and demonstrated using a case study. [ABSTRACT FROM AUTHOR]

Traditional rotor dynamics mainly focuses on the steady- state behavior of the rotor and shafting. However, for systems such as hydro turbine generating sets (HTGS) where the control and regulation is frequently applied, the shafting safety and stabilization in transient state is then a key factor. The shafting transient state inevitably involves multiparameter domain, multifield coupling, and coupling dynamics. In this paper, the relative value form of the Lagrange function and its equations have been established by defining the base value system of the shafting. Taking the rotation angle and the angular speed of the shafting as a link, the shafting lateral vibration and generator equations are integrated into the framework of generalized Hamiltonian system. The generalized Hamiltonian control model is thus established. To make the model more general, additional forces of the shafting are taken as the input excitation in proposed model. The control system of the HTGS can be easily connected with the shafting model to form the whole simulation system of the HTGS. It is expected that this study will build a foundation for the coupling dynamics theory using the generalized Hamiltonian theory to investigate coupling dynamic mechanism among the shafting vibration, transient of hydro turbine generating sets, and additional forces of the shafting. [ABSTRACT FROM AUTHOR]

This paper presents the result and analysis of the composition of energy loss occurring in the hydro turbine. Two new types of energy losses, namely the hydraulic loss in the flow channel and the impact loss, are defined. All losses within the hydro turbine are divided into four types and the loss coefficients are defined accordingly. Expressions or characteristic descriptions of these losses as well as the calibration method of the loss coefficients are presented. Furthermore, the torque model of the hydro turbine where the inner energy loss takes place is established. The developed model has been used to calculate the power loss due to the mechanical friction generated by the units' rotation to solve the difficulty of measurements of the mechanical friction loss in the hydro turbine. The definition of the impact loss explains the phenomenon that the loss of no-load is greater than that of the rated operation. A set of conversion coefficients are defined using the characteristic parameters at the rated operation, which are used to transform the parameters in the torque model into those that are easily measured. Therefore, the expression of the hydro turbine power is converted into a function that has the main servomotor displacement as its single variable. This makes the proposed model be convenient to use. Finally, the proposed model and methods are calibrated and verified using the measured data of a hydropower plant. Good agreement between the modeled results and the measurements indicates that the proposed model can represent the inner energy loss characteristics of the hydro turbine. [ABSTRACT FROM AUTHOR]

Xylem vessels are the channels used for water transport in Jatropha curcas L. Vessel complexity has a great influence on water transport. Therefore, using anatomical experiments and numerical simulations, the water transport characteristics of J. curcas L xylem vessels with perforation plate and secondary wall thickening (pit structures) were analyzed. The results showed that the xylem vessel in J. curcas provided a low resistance path. The xylem vessel resistance was composed of three elements: smooth vessels, secondary wall thickening and perforation plate. The proportion of smooth vessel resistance was the largest, accounting for 66.20% of the total resistance. Then the secondary wall thickening resistance accounted for 30.20% of the total resistance, and finally the perforation plate resistance accounted for 3.60% of the total resistance. The total resistance of the vessel model was positively correlated with the pit depth, perforation plate height and perforation plate width and negatively correlated with the vessel inner diameter and pit membrane permeability. The vessel inner diameter and the pit depth had a great influence on the total resistance. The total resistance of the vessel inner diameter of 52 µm was 89.15% higher than that of 61 µm, the total resistance of the pit depth of 5.6 µm was 21.98% higher than that of 2.6 µm. The pit structure in the secondary wall thickening caused the vessel to be transported radially, and the radial transmission efficiency of the vessel was positively correlated with the pit depth and pit membrane permeability and negatively correlated with the vessel inner diameter. The pit membrane permeability had the greatest influence on the radial transmission efficiency, and its radial transmission efficiency was 0–5.09%. [ABSTRACT FROM AUTHOR]