Search

Insufficient theoretical investigation is being conducted on the spectroscopic characteristics within the infrared wavelength range of SiP, an identified interstellar molecule. Using the ic-MRCI method, potential energy functions and dipole moment functions for the ground state (⁠|${X^2}\Pi $|⁠) and low excited states (⁠|${{\rm{A}}^2}{\Sigma ^ + }$|⁠) of the SiP molecule were calculated. Based on experimental spectroscopy data, least squares fitting was used for the potential energy functions of the |${X^2}\Pi $| and |${{\rm{A}}^2}{\Sigma ^ + }$| states. By combining these potential energy and dipole moment functions, the one-dimensional Schrödinger equation was solved to obtain the vibronic energy levels and Einstein A coefficients for the electronic states. Partition functions of the SiP molecule from 0.1 to 3000 K and the radiative properties of |${X^2}\Pi \leftrightarrow {X^2}\Pi $| and |${X^{\rm{2}}}\Pi \leftrightarrow {{\rm{A}}^2}{\Sigma ^ + }$| were derived. Infrared spectroscopy of the |${X^2}\Pi $| state and ultraviolet spectroscopy of the |${X^{\rm{2}}}\Pi \leftrightarrow {{\rm{A}}^2}{\Sigma ^ + }$| transition at 100 K, a temperature crucial for astronomical research, were calculated. Results indicate that the spectral-line intensity of the |${X^{\rm{2}}}\Pi \leftrightarrow {{\rm{A}}^2}{\Sigma ^ + }$| transition is greater, making it more suitable for astronomical observation. The obtained computational results in this paper yield spectroscopic parameters for the characterization of the interstellar molecule SiP, furnishing theoretical underpinnings for subsequent experimental observations. [ABSTRACT FROM AUTHOR]

In this paper, an array piezoelectric energy harvester (APEH) is designed for energy collection from water hydraulic system. The APEH is arranged in a spatial axial array, exhibiting excellent insulation and waterproof properties. The effects of connection modes and pressure pulsation parameters on the output performance of APEH are investigated through theoretical analysis, simulation and experiment. The results show that the output electric energy of each piezoelectric disk is consistent, and it is generated by the deformation caused by pressure pulsation. The connection modes show significant differences at different resistances. Series and parallel connections have the same maximum output power. The parallel connection has a smaller optimal resistance and has advantages in practical engineering applications. Both the pressure amplitude and the pulsation frequency affect the output voltage and power and increasing the pulsation frequency leads to the decrease of optimal resistance. By employing parallel connection, APEH can achieve higher output at lower load resistances. When the resistance is 12 kΩ, the average power and power density are reach as 997.63 μ W and 2.54 μ W mm−3, respectively. In summary, the APEH proposed in this paper offering a viable solution for energy recovery in water hydraulic systems and the sustainable power supply of the sensors, along with providing relevant theoretical references and practical schemes. [ABSTRACT FROM AUTHOR]

Background: Our previous study showed that calreticulin (CRT) promoted EGF-induced epithelial-mesenchymal transition (EMT) in pancreatic cancer (PC) via Integrin/EGFR-ERK/MAPK signaling. We next investigated the novel signal pathway and molecular mechanism involving the oncogenic role of CRT in PC. Methods: We investigated the potential role and mechanism of CRT in regulating intracellular free Ca2+ dependent acute and chronic endoplasmic reticulum stress (ERS)-induced EMT in PC in vitro and vivo. Results: Thapsigargin (TG) induced acute ERS via increasing intracellular free Ca2+ in PC cells, which was reversed by CRT silencing. Additionally, CRT silencing inhibited TG-induced EMT in vitro by reversing TG-induced changes of the key proteins in EMT signaling (ZO-1, E-cadherin and Slug) and ERK/MAPK signaling (pERK). TG-promoted cell invasion and migration was also rescued by CRT silencing but enhanced by IRE1α silencing (one of the key stressors in unfolded protein response). Meanwhile, CRT was co-immunoprecipitated and co-localized with IRE1α in vitro and its silencing led to the chronic ERS via upregulating IRE1α independent of IRE1-XBP1 axis. Moreover, CRT silencing inhibited IRE1α silencing-promoted EMT, including inhibiting the activation of EMT and ERK/MAPK signaling and the promotion of cell mobility. In vivo, CRT silencing decreased subcutaneous tumor size and distant liver metastasis following with the increase of IRE1α expression. A negative relationship between CRT and IRE1α was also observed in clinical PC samples, which coordinately promoted the advanced clinical stages and poor prognosis of PC patients. Conclusions: CRT promotes EMT in PC via mediating intracellular free Ca2+ dependent TG-induced acute ERS and IRE1α-mediated chronic ERS via Slug and ERK/MAPK signaling. [ABSTRACT FROM AUTHOR]