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The use of two-dimensional (2D) layered metal-organic frameworks (MOFs) as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium (Se)-containing electrocatalysts for overall water splitting. Herein, two strategies are then utilized to introduce Se element into the Co–Fe MOF, one being the etching of as-prepared MOF by SeO2 solution, and the other, the replacing of SCN− with SeCN− as the construction unit. The electrochemical activity of the pristine 2D MOF and their calcinated derivatives for catalyzing the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is evaluated and further discussed. It is found that the effect of introducing Se on improving electrochemical catalytic activity is significant for the HER process. Specifically, the calcinated derivative in the replacing method exhibits an overpotential of 235 mV for HER and 270 mV for OER at a current density of 10 mA/cm2. For comparing the two methods of introducing Se element into MOF, similar electrocatalytic activity can be achieved on the their calcinated derivatives. The high electrochemical performance of 2D CoFe-MOF derivatives may be resulted from the unique 2D hierarchical porous structure and strong synergistic effect between different components in the material. [ABSTRACT FROM AUTHOR]

Carotenoids are natural lipophilic pigments, which have been proven to provide significant health benefits to humans, relying on their capacity to efficiently scavenge singlet oxygen and peroxyl radicals as antioxidants. Strains belonging to the genus Rhodosporidium represent a heterogeneous group known for a number of phenotypic traits including accumulation of carotenoids and lipids and tolerance to heavy metals and oxidative stress. As a representative of these yeasts, Rhodosporidium toruloides naturally produces carotenoids with high antioxidant activity and grows on a wide variety of carbon sources. As a result, R. toruloides is a promising host for the efficient production of more value-added lipophilic compound carotenoids, e.g., torulene and torularhodin. This review provides a comprehensive summary of the research progress on carotenoid biosynthesis in R. toruloides, focusing on the understanding of biosynthetic pathways and the regulation of key enzymes and genes involved in the process. Moreover, the relationship between the accumulation of carotenoids and lipid biosynthesis, as well as the stress from diverse abiotic factors, has also been discussed for the first time. Finally, several feasible strategies have been proposed to promote carotenoid production by R. toruloides. It is possible that R. toruloides may become a critical strain in the production of carotenoids or high-value terpenoids by genetic technologies and optimal fermentation processes. Key points: • Biosynthetic pathway and its regulation of carotenoids in Rhodosporidium toruloides were concluded • Stimulation of abiotic factors for carotenoid biosynthesis in R. toruloides was summarized • Feasible strategies for increasing carotenoid production by R. toruloides were proposed [ABSTRACT FROM AUTHOR]

This research explores the thermodynamic properties of the Euler-Heisenberg-AdS black hole under new higher order generalized uncertainty principle. We investigate the thermodynamics of the Euler-Heisenberg-AdS black hole in the context of the GUP and the thermodynamics of the high-order QED correction to the Euler-Heisenberg-AdS black hole in the same context. The corresponding deformed expressions of the Hawking temperature, the heat capacity, the remnant mass, entropy function are obtained, and in order to better understand these structures, we demonstrate some figures. [ABSTRACT FROM AUTHOR]

This study explores the relationship among left-behind adolescent's perceived discrimination, parent-adolescent cohesion, resilience and school adaptation. A total of 460 students from rural middle school were tested, using Perceived Discrimination Questionnaire, Parent-Adolescent Cohesion Questionnaire, Resilience Scale, and School Adaptation Scale. Correlation analysis shows that perceived discrimination is negatively correlated with resilience and school adaptation, while parent-adolescent cohesion is positively correlated with resilience and school adaptation. Further analysis reveals that resilience plays a mediating role between perceived discrimination and school adaptation; the first stage of the indirect effect is moderated by parent-adolescent cohesion. This study provided a better understanding on left-behind adolescent's perceived discrimination and school adaptation, and threw light on the improvement of left-behind adolescent's school adaptation. [ABSTRACT FROM AUTHOR]

Using titanium sulfate as titanium source, hydrofluoric acid as fluorine source, bayberry tannin (BT) as template and ammonia as precipitant, nano fluorinated titanium dioxide (BT-FTO) with porous structure was prepared by simple precipitation method. X-ray diffraction (XRD), scanning electron micro-scopy (SEM), specific surface area analyzer (BET), UV–Vis absorption spectroscopy (UV–Vis Abs), X-ray photoelectron spectroscopy (XPS) and molecular fluorescence spectrophotometer (PL) were used to analyze the crystal phase composition, surface morphology, specific surface area, UV absorption band edge, element composition, valence state and fluorescence intensity of the samples. The photocatalytic activity of the photocatalyst for methyl orange was explored. The results indicate that: BT-FTO nanoparticles are well dispersed; fluorination promotes the formation of hydroxyl groups on the surface of titanium dioxide; the specific surface area of titanium dioxide is enhanced by bayberry tannin modification; fluorination as well as tannin modification are able to reduce the grain size of TiO2; when 0.0188% BT-FTO calcined at 550°C was irradiated by a 500 W metal halide lamp for 30 min, the degradation rate of methyl orange reached 94%, while that of simple titanium dioxide was only 37.87%. [ABSTRACT FROM AUTHOR]

TAR DNA-Binding Protein 43 (TDP-43) has been well studied in neurodegenerative diseases, but its potential role in malignance is still unclear. Here, we demonstrate that TDP-43 contributes to the suppression of apoptosis by facilitating lipid metabolism in hepatocellular carcinoma (HCC). In HCC cells, TDP-43 is able to suppress apoptosis while deletion of it markedly induces apoptosis. RNA-sequencing identifies the lipid metabolism gene abhydrolase domain containing 2 (ABHD2) as the target gene of TDP-43. Tissue microarray analysis shows the positive correlation of TDP-43 and ABHD2 in HCC. Mechanistically, TDP-43 binds with the UG-rich sequence1 of ABHD2 3'UTR to enhance the mRNA stability of ABHD2, thereby upregulating ABHD2. Afterwards, TDP-43 promotes the production of free fatty acid and fatty acid oxidation-originated reactive oxygen species (ROS) in an ABHD2-dependent manner, so as to suppress apoptosis of HCC. Our findings provide insights into the mechanism of HCC progression and reveal TDP-43/ABHD2 as potential targets for the precise treatment of HCC. TDP-43 acts as an RNA-binding protein that regulates the RNA stability of ABHD2 and affects the release of fatty acids and ROS, which in turn regulates apoptosis and affects the growth of liver tumors. [ABSTRACT FROM AUTHOR]

In this work, the thermodynamics of the Bardeen black hole with quintessence matter associated with dark energy in the context of the extended generalized uncertainty principle is investigated. The corrections to the Hawking temperature, heat capacity, and entropy are obtained via a heuristic method. These modifications show that the modified uncertainty principles and normalization factor will restrict the lower bound value of horizon radius to affect the Hawking temperature, the remnant temperature and mass do not depend on the extended uncertainty principle parameter and the quintessence matter will not affect the entropy of the Bardeen black hole. In addition, the equation of state associated with the pressure and the volume are examined. [ABSTRACT FROM AUTHOR]

Background: Professional identity formation (PIF) in medical students is a multifactorial phenomenon, shaped by ways that clinical and non-clinical experiences, expectations and environmental factors merge with individual values, beliefs and obligations. The relationship between students' evolving professional identity and self-identity or personhood remains ill-defined, making it challenging for medical schools to support PIF systematically and strategically. Primarily, to capture prevailing literature on PIF in medical school education, and secondarily, to ascertain how PIF influences on medical students may be viewed through the lens of the ring theory of personhood (RToP) and to identify ways that medical schools support PIF. Methods: A systematic scoping review was conducted using the systematic evidence-based approach. Articles published between 1 January 2000 and 1 July 2020 related to PIF in medical students were searched using PubMed, Embase, PsycINFO, ERIC and Scopus. Articles of all study designs (quantitative and qualitative), published or translated into English, were included. Concurrent thematic and directed content analyses were used to evaluate the data. Results: A total of 10443 abstracts were identified, 272 full-text articles evaluated, and 76 articles included. Thematic and directed content analyses revealed similar themes and categories as follows: characteristics of PIF in relation to professionalism, role of socialization in PIF, PIF enablers and barriers, and medical school approaches to supporting PIF. Discussion: PIF involves iterative construction, deconstruction and inculcation of professional beliefs, values and behaviours into a pre-existent identity. Through the lens of RToP, factors were elucidated that promote or hinder students' identity development on individual, relational or societal levels. If inadequately or inappropriately supported, enabling factors become barriers to PIF. Medical schools employ an all-encompassing approach to support PIF, illuminating the need for distinct and deliberate longitudinal monitoring and mentoring to foster students' balanced integration of personal and professional identities over time. [ABSTRACT FROM AUTHOR]

In view of the problems existing in the evaluation process of slope stability in cold regions, the improved entropy weight method and extension theory are used to evaluate the slope stability. Nine indexes which affect the slope stability in cold regions are selected, the matter element system of slope stability evaluation is established by extension theory, and the extension correlation degree between evaluation index and evaluation grade is calculated. The improved entropy weight method is used to calculate the entropy weight of the matter element index system, and then the stability grade of the slope matter element is determined. Based on the extension theory and improved entropy weight method, the slope stability of Beizhan open pit mine is predicted. The results show that the prediction results are consistent with the actual situation of the project, and the evaluation method can be applied to the slope stability evaluation in cold regions. By using extension theory and improved entropy weight method, the evaluation index can be changed from a single determined value to an interval value, and the influence degree of the evaluation index can be analyzed more comprehensively. This method improves the evaluation accuracy and provides a new method for the slope stability evaluation in cold regions. [ABSTRACT FROM AUTHOR]

Glutathione peroxidase 4 (GPX4) utilizes glutathione (GSH) to detoxify lipid peroxidation and plays an essential role in inhibiting ferroptosis. As a selenoprotein, GPX4 protein synthesis is highly inefficient and energetically costly. How cells coordinate GPX4 synthesis with nutrient availability remains unclear. In this study, we perform integrated proteomic and functional analyses to reveal that SLC7A11-mediated cystine uptake promotes not only GSH synthesis, but also GPX4 protein synthesis. Mechanistically, we find that cyst(e)ine activates mechanistic/mammalian target of rapamycin complex 1 (mTORC1) and promotes GPX4 protein synthesis at least partly through the Rag-mTORC1-4EBP signaling axis. We show that pharmacologic inhibition of mTORC1 decreases GPX4 protein levels, sensitizes cancer cells to ferroptosis, and synergizes with ferroptosis inducers to suppress patient-derived xenograft tumor growth in vivo. Together, our results reveal a regulatory mechanism to coordinate GPX4 protein synthesis with cyst(e)ine availability and suggest using combinatorial therapy of mTORC1 inhibitors and ferroptosis inducers in cancer treatment. [ABSTRACT FROM AUTHOR]

The superposition of different statistics defines the concept of superstatistics, which makes an equilibrium statistical mechanics incorporate fluctuations. Herein, we study the thermodynamical properties of the anharmonic oscillator for Dirac equation in commutative and noncommutative (NC) spaces using q-deformed superstatistics. By employing the biconfluent Heun functions, the energy spectrum and the wave functions of the considered system are expressed in explicit form. Moreover, the thermodynamical properties of the anharmonic oscillator ensemble in terms of the effective Boltzmann factor are derived, and in order to illustrate the results, some figures are plotted for the clarity of our results. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science A is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sanshandao Xinli Gold Mine in Shandong Province is the first Chinese subsea gold mine. The mine uses cement backfill in the open stopes. The existence of a high concentration of Cl− in the water use to create the cement backfill affects its strength. An analysis by scanning electron microscopy and x-ray diffraction investigated the effect of salt brine on mechanical properties of cement backfill and micro-corrosion mechanism, the suitable mineral admixture of fly ash was selected after conducting theoretical analysis to decrease the effects of brine. A relationship between the elastic modulus and the uniaxial compressive strength of the cemented backfill was determined. The density, cohesion and internal friction angle of the cemented backfill were obtained. Based on x-ray diffraction analysis of fly ash, scanning electron microscope test and testing the addition of fly ash in varying amounts and ways of introduction, the mechanism for improving the uniaxial compressive strength of the cement backfill produced with the fly ash and the best mixing quantity of the fly ash was determined in briny conditions through experiments and theoretical research. Rheological properties of the filling slurry with fly ash were also investigated. [ABSTRACT FROM AUTHOR]

In this study, carbohydrates (cellulose plus hemicellulose) in corncob were effectively converted furfuralcohol (FOL) via chemical-enzymatic catalysis in a one-pot manner. After corncob (2.5 g, dry weight) was pretreated with 0.5 wt% oxalic acid, the obtained corncob-derived xylose (19.8 g/L xylose) could be converted to furfural at 60.1% yield with solid acid catalyst SO42−/SnO2-attapulgite (3.6 wt% catalyst loading) in the water-toluene (3:1, v/v) at 170 °C for 20 min. Moreover, the oxalic acid-pretreated corncob residue (1.152 g, dry weight) was enzymatically hydrolyzed to 0.902 g glucose and 0.202 g arabinose. Using the corncob-derived glucose (1.0 mM glucose/mM furfural) as cosubstrate, the furfural liquor (48.3 mM furfural) was successfully biotransformed to FOL by recombinant Escherichia coli CCZU-A13 cells harboring an NADH-dependent reductase (SsCR) in the water-toluene (4:1, v/v) under the optimum conditions (50 mM PEG-6000, 0.2 mM Zn2+, 0.1 g wet cells/mL, 30 °C, pH 6.5). After the bioreduction for 2 h, FAL was completely converted to FOL. The FOL yield was obtained at 0.11 g FOL/g corncob. Clearly, this one-pot synthesis strategy shows high potential application for the effective synthesis of FOL. [ABSTRACT FROM AUTHOR]

The pathogenesis and therapeutic treatment of intrauterine adhesions (IUAs) remain unsolved, highlighting the need for stable and effective experimental animal models. In this study, uterine electrocoagulation of twenty-one female New Zealand White rabbits was carried out to establish an IUA model. As rabbits have two completely separate uterine horns, each rabbit had its own internal control: one uterine horn was given an electrothermal injury (Group A, n=21), and the contralateral uterine horn received no treatment and served as the control (Group B, n=21). The endometrial morphology, number of endometrial glands, area of endometrial fibrosis, and number of implanted fetuses were compared between the two groups. In Group A, the numbers of endometrial glands on Days 7 and 14 and the number of implanted fetuses were significantly lower than those in Group B (P<0.05, P<0.05, and P<0.01, respectively), while the ratio of the area with endometrial stromal fibrosis to the total endometrial area was significantly increased (P<0.01). These results suggest that this method of electrothermal injury is effective for the establishment of a rabbit IUA model between 7 and 14 d after surgery. [ABSTRACT FROM AUTHOR]

Objective: The purpose of the article is to evaluate the changes in lipid metabolism in bovine mammary-gland epithelial MAC-T cells after PKM2 knockdown.Results: MAC-T cells stably expressing low levels of PKM2 were established with lentivirus-mediated small hairpin RNA. Although the knockdown of PKM2 had no effect on MAC-T cell growth, the reduced expression of PKM2 attenuated the mRNA and protein expression of key enzymes involved in sterol synthesis through the SREBP pathway.Conclusions: The downregulation of PKM2 significantly influenced lipid synthesis in bovine mammary-gland epithelial MAC-T cells. These findings extend our understanding of the crosstalk between glycolysis and lipid metabolism in bovine mammary-gland epithelial cells. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a serious-threatening complication of diabetes and urgently needed to be treated. Evidence has accumulated indicating that microglia inflammation within the retina plays a critical role in DR. Microglial matrix metalloproteinase 9 (MMP-9) has an important role in the destruction of the integrity of the blood-retinal barrier (BRB) associated with the development of DR. MMP-9 was also considered important for regulating inflammatory responses. Paeoniflorin, a monoterpene glucoside, has a potent immunomodulatory effect on microglia. We hypothesized that paeoniflorin could significantly suppress microglial MMP-9 activation induced by high glucose and further relieve DR. BV2 cells were used to investigate the effects and mechanism of paeoniflorin. The activation of MMP-9 was measured by gelatin zymography. Cell signaling was measured by western blot assay and immunofluorescence assay. High glucose increased the activation of MMP-9 in BV2 cells, which was abolished by HMGB1, TLR4, p38 MAPK, and NF-κB inhibition. Phosphorylation of p38 MAPK induced by high glucose was decreased by TLR4 inhibition in BV2 cells. Paeoniflorin induced suppressor of cytokine signaling 3 (SOCS3) expression and reduced MMP-9 activation in BV2 cells. The effect of paeoniflorin on SOCS3 was abolished by the TLR4 inhibitor. In streptozotocin (STZ)-induced diabetes mice, paeoniflorin induced SOCS3 expression and reduced MMP-9 activation. Paeoniflorin suppressed STZ-induced IBA-1 and IL-1β expression and decreased STZ-induced high blood glucose level. In conclusion, paeoniflorin suppressed high glucose-induced retinal microglia MMP-9 expression and inflammatory response via inhibition of the TLR4/NF-κB pathway through upregulation of SOCS3 in diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Using the momentum space representation, we study the quantum features of the two-dimensional Duffin-Kemmer-Petiau (DKP) oscillator under the condition that the position and the momentum operator obey the generalized commutation relation that leads to the appearance of minimal length with the order of the Planck length. In this context, the energy spectrum, the wave function, the probability densities and the corresponding thermodynamic functions of the DKP oscillator for spin-0 and spin-1 are obtained, respectively. They depend explicitly on the deformed parameter a which characterizes the structure of the considered system and its finite size. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhejiang University: Science B is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel coordination polymer with 4-sulfonyl-2,6-naphthalenedicarboxylic acid (HSNDC), {[Cd(NDSC)(HO)]·6HO} ( 1), has been prepared and characterized by single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P2/ c with a = 12.324(4), b = 22.572(7), c = 7.1472 Å, β = 91.469(5)°, V = 1987.4(11) Å. In the structure, the ligands use the carboxylate groups to connect Cd(II) ions into 1D chains, and the chains are linked into 2D undulated layers through the coordination of the sulfonate groups to additional Cd(II) ions. The compound exhibits two distinct weight loss steps due to the release of all water molecules and the decomposition of the SNDC ligand, and it displays photoluminescence around 448 nm, which is blue-shifted compared with the ligand. Index Abstract: A new Cd(II) coordination polymer with 4-sulfonyl-2, 6-naphthalenedicarboxylate (NDSC) is reported. The NDSC ligand anions act as T-shape building blocks to link the metal ions into a two-dimensional coordination network resembling the brick-wall topology.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Exposure of cells to various stresses often leads to the induction of a group of proteins called heat shock proteins (HSPs, molecular chaperones). Hsp70 is one of the most highly inducible molecular chaperones, but its expression must be maintained at low levels under physiological conditions to permit constitutive cellular activities to proceed. Heat shock transcription factor 1 (HSF1) is the transcriptional regulator of HSP gene expression, but it remains poorly understood how newly synthesized HSPs return to basal levels when HSF1 activity is attenuated. CHIP (carboxy terminus of Hsp70-binding protein), a dual-function co-chaperone/ubiquitin ligase, targets a broad range of chaperone substrates for proteasomal degradation. Here we show that CHIP not only enhances Hsp70 induction during acute stress but also mediates its turnover during the stress recovery process. Central to this dual-phase regulation is its substrate dependence: CHIP preferentially ubiquitinates chaperone-bound substrates, whereas degradation of Hsp70 by CHIP-dependent targeting to the ubiquitin–proteasome system occurs when misfolded substrates have been depleted. The sequential catalysis of the CHIP-associated chaperone adaptor and its bound substrate provides an elegant mechanism for maintaining homeostasis by tuning chaperone levels appropriately to reflect the status of protein folding within the cytoplasm. [ABSTRACT FROM AUTHOR]

In this paper, the roles of low velocity and high conductivity body inside the crust in the process of strong earthquake preparation are approached by using theoretical analysis method based on the comprehensive researches on the fine structure of strong seismic source in the North China. The following results are obtained. The low-velocity and high-conductivity body plays the promoting role for the action of deep-seated structure in the medium stage of earthquake preparation, except that its existence is advantageous to the stress concentrating in the overlying brittle layer during the process of earthquake preparation. And it plays the triggering role for the occurrence of strong earthquake in the later stage of earthquake preparation. [ABSTRACT FROM AUTHOR]

According to the precursory data of the 1976 Tangshan earthquake ( M = 7.8), and combining with the research results of rock fracture, seismic source, tectonics, seismic precursors, dynamic condition and crust structure, the seismogenic process of Tangshan earthquake has been numerically simulated by using the model of water-saturated porous medium with a rhombic hard inclusion. First, a system of seismogenic dynamics equations of solid-liquid two-phase medium has been set up under considering rock inelastic dilation, strain-softening and pore-water permeation. Then, the finite difference method to solve the equation system in incremental form has been presented. Finally, the seismogenic process of Tangshan earthquake and the temporal-spatial characteristics of its precursors have been numerically simulated when the hard inclusion includes a soft fault belt. The numerically simulating result shows that the development of Tangshan earthquake mainly undergoes following processes: elastic accumulation, early inelastic cubic dilation, accelerative softening (failure and creep) of fault first time, inelastic dilation twice in Tianjin—Ninghe area, accelerative softening of fault twice and instability. Corresponding to the fault accelerative softening, elastic recovery and inelastic dilation twice in some parts of seismogenic medium. By comparing with the data of precursory observation, ones can find the preceding simulating result explains the varied characters of practical data better. Meanwhile, the numerical simulation further displays the temporal-spatial change law and complex patterns of the field of Tangshan earthquake development as well. It makes a base study for the physical mechanism of change of the seismic precursory field. [ABSTRACT FROM AUTHOR]

Based on a simplified media model of Gonghe area, the precursor characteristics of Gonghe M7.0 earthquake in 1990 are simulated in this paper by using the constitutive relationship of binary medium (solid and water). The results show that the simulated state distribution and extension variation of media are identical with the spatial and temporal distribution of reliable anomalies before Gonghe earthquake. The study also suggests that the development of the Gonghe earthquake has experienced a series of processes such as elastic deformation of large scale, early nonelastic dilatation, strain softening and elastic recovery in the neighbour region of Xining, nonelastic dilatation of high dense block near seismic source and earthquake occurrence. Therefore, it can be concluded that this earthquake development is neither a simple process for fissures developing and linking up with one another, nor a process of nonelastic volume expansion and water flowing into medium around seismic source, contrary, it is a complicated medium state changing process, and the style of such changing depends on geological structure environment of seismic source and its neighbour region. It is considered that different earthquakes are accompanied by different geological conditions, the spatial and temporal behavior of their precursors are certainly different. [ABSTRACT FROM AUTHOR]