The relationship between psychological capital, burnout and perceived stress in junior nurses: a latent profile analysis.

Background: Psychological capital, an intrinsic personal asset, enhances junior nurses' ability to navigate transition and sustain superior job performance. This study aimed to classify junior nurses into distinct psychological capital profiles and examine their associations with burnout and perceived stress levels. Methods: A cross-sectional study involving 480 junior nurses from three hospitals in Beijing assessed psychological capital, stress, and burnout using e-questionnaires, from July 2021 to August 2022. We employed exploratory latent profile analysis for psychological capital profiling and logistic regression with the best subset method to identify the influential factors. Results: The results of the latent profile analysis supported the models of two latent profiles, which were defined as low psychological capital (224, 46.5%) and high psychological capital (256, 53.5%). Logistic regression revealed that introverted nurses and those experiencing moderate to high levels of burnout and stress were more likely to exhibit low psychological capital. Conclusion: Nursing management should proactively identify and support junior nurses with low psychological capital, with a focus on introverted individuals, to mitigate the impact of stress and burnout.

Perceived stress and brain connectivity in subthreshold depression: Insights from eyes-closed and eyes-open states.

Perceived stress is an acknowledged risk factor for subthreshold depression (StD), and fluctuations in perceived stress are thought to disrupt the harmony of brain networks essential for emotional and cognitive functioning. This study aimed to elucidate the relationship between eye-open (EO) and eye-closed (EC) states, perceived stress, and StD. We recruited 27 individuals with StD and 33 healthy controls, collecting resting state fMRI data under both EC and EO conditions. We combined intrinsic connectivity and seed-based functional connectivity analyses to construct the functional network and explore differences between EC and EO conditions. Graph theory analysis revealed weakened connectivity strength in the right superior frontal gyrus (SFG) and right median cingulate and paracingulate gyrus (MCC) among participants with StD, suggesting an important role for these regions in the stress-related emotions dysregulation. Notably, altered SFG connectivity was observed to significantly relate to perceived stress levels in StD, and the SFG connection emerges as a neural mediator potentially influencing the relationship between perceived stress and StD. These findings highlight the role of SFG and MCC in perceived stress and suggest that understanding EC and EO states in relation to these regions is important in the neurobiological framework of StD. This may offer valuable perspectives for early prevention and intervention strategies in mental health disorders.

A study on expression recognition based on improved mobilenetV2 network.

This paper proposes an improved strategy for the MobileNetV2 neural network(I-MobileNetV2) in response to problems such as large parameter quantities in existing deep convolutional neural networks and the shortcomings of the lightweight neural network MobileNetV2 such as easy loss of feature information, poor real-time performance, and low accuracy rate in facial emotion recognition tasks. The network inherits the characteristics of MobilenetV2 depthwise separated convolution, signifying a reduction in computational load while maintaining a lightweight profile. It utilizes a reverse fusion mechanism to retain negative features, which makes the information less likely to be lost. The SELU activation function is used to replace the RELU6 activation function to avoid gradient vanishing. Meanwhile, to improve the feature recognition capability, the channel attention mechanism (Squeeze-and-Excitation Networks (SE-Net)) is integrated into the MobilenetV2 network. Experiments conducted on the facial expression datasets FER2013 and CK + showed that the proposed network model achieved facial expression recognition accuracies of 68.62% and 95.96%, improving upon the MobileNetV2 model by 0.72% and 6.14% respectively, and the parameter count decreased by 83.8%. These results empirically verify the effectiveness of the improvements made to the network model.

DMF as an amine source: iron-catalyzed cyclization of 2H-azirines to imidazoles.

A novel method has been developed for the synthesis of 1-methyl-4,5-diaryl-1H-imidazoles through Fe(II)-catalyzed cyclization of 2H-azirines and N,N-dimethylformamide (DMF) as an amine source. This transformation involves the cleavage of C-N and CN double bonds and the construction of new C-N and CN double bonds. The reaction has readily available starting materials, a wide range of substrates and mild reaction conditions. In addition, the reaction also facilitated the convenient synthesis of 1-methyl-2,4,5-triaryl-1H-imidazoles.

Fluorine-thiol displacement probes for acetaminophen's hepatotoxicity.

Chemicals possessing reactive electrophiles can denature innate proteins leading to undesired toxicity, and the overdose-induced liver injury by drugs containing electrophiles has been one of the major causes of non-approval and withdraw by the US Food and Drug Administration (FDA). Elucidating the associated proteins could guide the future development of therapeutics to circumvent these drugs' toxicities, but was largely limited by the current probing tools due to the steric hindrance of chemical tags including the common "click chemistry" labels. Taking the widely used non-steroidal anti-inflammatory drug acetaminophen (APAP) as an example, we hereby designed and synthesized an APAP analogue using fluorine as a steric-free label. Cell toxicity studies indicated our analogue has similar activity to the parent drug. This analogue was applied to the mouse hepatocellular proteome together with the corresponding desthiobiotin-SH probe for subsequent fluorine-thiol displacement reactions (FTDRs). This set of probes has enabled the labeling and pull-down of hepatocellular target proteins of the APAP metabolite as validated by Western blotting. Our preliminary validation results supported the interaction of APAP with the thioredoxin protein, which is an important redox protein for normal liver function. These results demonstrated that our probes confer minimal steric perturbation and mimic the compounds of interest, allowing for global profiling of interacting proteins. The fluorine-thiol displacement probing system could emerge as a powerful tool to enable the investigation of drug-protein interactions in complex biological environments.

Elevating Air Temperature May Enhance Future Epidemic Risk of the Plant Pathogen Phytophthora infestans.

Knowledge of pathogen adaptation to global warming is important for predicting future disease epidemics and food production in agricultural ecosystems; however, the patterns and mechanisms of such adaptation in many plant pathogens are poorly understood. Here, population genetics combined with physiological assays and common garden experiments were used to analyze the genetics, physiology, and thermal preference of pathogen aggressiveness in an evolutionary context using 140 Phytophthora infestans genotypes under five temperature regimes. Pathogens originating from warmer regions were more thermophilic and had a broader thermal niche than those from cooler regions. Phenotypic plasticity contributed ~10-fold more than heritability measured by genetic variance. Further, experimental temperatures altered the expression of genetic variation and the association of pathogen aggressiveness with the local temperature. Increasing experimental temperature enhanced the variation in aggressiveness. At low experimental temperatures, pathogens from warmer places produced less disease than those from cooler places; however, this pattern was reversed at higher experimental temperatures. These results suggest that geographic variation in the thermal preferences of pathogens should be included in modeling future disease epidemics in agricultural ecosystems in response to global warming, and greater attention should be paid to preventing the movement of pathogens from warmer to cooler places.

Influence of organoboron cross-linker and reservoir characteristics on filtration and reservoir residual of guar gum fracturing fluid in low-permeability shale gas reservoirs.

To effectively reduce the filtration rate of water-based fracturing fluid and promote the pressure holding effect of fracturing fluid in underground unconventional reservoirs, an efficient and clean organic-boron cross-linker was synthesized with boric acid and low alcohols. The results obtained that the synthesized organoboron cross-linker exhibits better fluid loss performance to water-based fracturing fluid than the commercially available cross-linker. This organoboron cross-linker allowed decreasing filtration coefficient more than 0.74 × 10-2 m3·min1/2 as a result of the network structure formed by the organoboron cross-linker and guar gum molecule. However, commercially available cross-linker exhibits a relatively large filtered mass of water more than 1.33 × 10-2 m3·min1/2 at the same condition. Meanwhile, the cross-linked guar gum fracturing fluid can significantly improve the fluid loss property with the increase of cross-linker content and pressure, and an increased fluid filtration gradually was revealed with increasing the reservoir temperature and current speed. Moreover, the damage of shale reservoir caused by the prepared boron cross-linker was only 11%, which was lower than 18% of the commercial boron cross-linker under the same conditions.

Calculation model and experimental study of the collapse strength of titanium alloy tubing and casing.

Titanium alloy has become a promising candidate material for oil country tubular goods (OCTGs) in harsh service environments owing to its high specific strength, low density, low elastic modulus, excellent toughness, excellent anti-fatigue and corrosion resistance. However, because the high-quality natural gas resources in China are mainly concentrated deep underground, titanium alloy tubing and casing will bear great external pressure loads underground, so the collapse strength of titanium alloy tubing and casing is very important for the safety of the string in the well. In this paper, a new collapse strength calculation model, the strength collapse criterion model (SCM), was proposed for titanium alloy tubing and casing. 35 different specifications of titanium alloy tubing and casing were selected for the full-scale collapse tests to verify the reliability of the established SCM model. Furthermore, the effect of different key parameters (such as strength, ovality, eccentricity and residual stress) on collapse strength of titanium alloy pipes were investigated systematically and compared with the same specifications of steel pipes. The strength collapse criterion model and analysis results can provide a technical reference for the design and use of titanium alloy OCTGs in the petroleum and natural gas industries.

Unprotected peptide macrocyclization and stapling via a fluorine-thiol displacement reaction.

We report the discovery of a facile peptide macrocyclization and stapling strategy based on a fluorine thiol displacement reaction (FTDR), which renders a class of peptide analogues with enhanced stability, affinity, cellular uptake, and inhibition of cancer cells. This approach enabled selective modification of the orthogonal fluoroacetamide side chains in unprotected peptides in the presence of intrinsic cysteines. The identified benzenedimethanethiol linker greatly promoted the alpha helicity of a variety of peptide substrates, as corroborated by molecular dynamics simulations. The cellular uptake of benzenedimethanethiol stapled peptides appeared to be universally enhanced compared to the classic ring-closing metathesis (RCM) stapled peptides. Pilot mechanism studies suggested that the uptake of FTDR-stapled peptides may involve multiple endocytosis pathways in a distinct pattern in comparison to peptides stapled by RCM. Consistent with the improved cell permeability, the FTDR-stapled lead Axin and p53 peptide analogues demonstrated enhanced inhibition of cancer cells over the RCM-stapled analogues and the unstapled peptides.

From Mo-Si-B to Mo-Ti-Si-B Alloys: A Short Review.

Mo-Si-B alloys have attracted considerable research interest during the last several decades due to their high melting points, excellent high-temperature strength and relatively good oxidation resistance. However, insufficient room-temperature fracture toughness and high-temperature oxidation resistance restrain their further application. Generally, a sufficient volume fraction of BCC-Mo solid-solution phase, providing the ductility, and a high Si content, responsible for the formation of passive oxide scales, is difficult to achieve simultaneously in this ternary system. Recently, macroalloying of Ti has been proposed to establish a novel phase equilibrium with a combination of enough BCC phase and intermetallic compounds that contain a large amount of Si. In this article, the development history from the ternary Mo-Si-B to the quaternary Mo-Ti-Si-B system was reviewed. It was found that the constitution phases could be easily tailored by changing the Ti content. In this regard, better performance of mechanical properties and oxidation resistance can be obtained through proper alloy design. In-depth understanding of the advantages of the quaternary alloys over their ternary ancestors may contribute to bringing about a new concept in designing novel ultra-high-temperature structural materials.

Iodine-Mediated Cyclization of Enamines to Imidazole-4-Carboxylic Derivatives with Sequential Removal of Nitrogen Atoms from TMSN3.

An iodine-mediated oxidative [4+1] cyclization of enamines with TMSN3 for the synthesis of 2,5-disubstituted imidazole-4-carboxylic derivatives has been developed. The mechanistic studies revealed that the reaction proceeds through a sequential removal of two nitrogen atoms from TMSN3. The synthetic utility was further demonstrated with a gram-scale reaction and various derivatization transformations of the products.

Iron-Catalyzed Cycloaddition of Amides and 2,3-Diaryl-2H-azirines To Access Oxazoles via C-N Bond Cleavage.

A novel and efficient iron-catalyzed cycloaddition reaction using readily available 2,3-diaryl-2H-azirines and primary amides is reported. A wide range of trisubstituted oxazoles could be achieved in good yields with good functional group compatibility. In this transformation, two C-N bonds were cleaed and new C-N and C-O bonds were formed.

Evodiamine inhibits high-fat diet-induced colitis-associated cancer in mice through regulating the gut microbiota.

OBJECTIVE: High-fat diet is one of the main risk factors that disrupt the balance of gut microbiota, which eventually will induce colorectal cancer (CRC). Evodiamine (EVO) is a wildly used multifunctional traditional Chinese medicine extract. In this study, we investigated the role of gut microbiota in high-fat diet-propelled CRC and the potential of EVO for CRC chemoprevention. METHODS: Gut microbiota, serum d-lactic acid and endotoxin from 38 patients with colon cancer and 18 healthy subjects were detected by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). In addition, body mass index, phospho-signal transducer and activator of transcription 3 (p-STAT3) expression in cancer tissues and paracancerous tissues were detected by immunohistochemistry. A mouse intestinal inflammatory tumor model was established by azomethane/sodium dextran sulfate, followed by treatment with EVO and 5-aminosalicylic acid (ASA). Gut microbiota and inflammatory factors were detected by quantitative polymerase chain reaction, while serum d-lactic acid and endotoxin were detected by ELISA. Furthermore, cell proliferation, cell apoptosis, and interleukin (IL)-6/STAT3/P65 pathway were evaluated by 5-ethynyl-2'-deoxyuridine, terminal-deoxynucleotidyl transferase-mediated nick-end labeling, and Western blot assays. RESULTS: In patients with colon cancer, the numbers of Enterococcus faecalis and Escherichia coli were increased, while those of Bifidobacterium, Campylobacter and Lactobacillus were decreased. Serum endotoxin and d-lactic acid levels and p-STAT3 levels were significantly increased. In the mouse model, both EVO and ASA inhibited tumor formation, decreased the proliferation of tumor cells, and induced apoptosis of tumor cells. Compared with the control group, the numbers of E. faecalis and E. coli were decreased, while Bifidobacterium, Campylobacter and Lactobacillus numbers were increased. In the EVO group, serum endotoxin and d-lactic acid levels and inflammatory factors were significantly decreased. Further, the IL6/STAT3/P65 signaling pathway was inhibited in the EVO group. CONCLUSION: EVO may inhibit the occurrence of colon cancer by regulating gut microbiota and inhibiting intestinal inflammation. The potential mechanism involves inhibition of the IL6/STAT3/P65 signaling pathway, revealing its potential therapeutic significance in clinical applications.

IBX-Promoted Oxidative Cyclization of N-Hydroxyalkyl Enamines: A Metal-Free Approach toward 2,3-Disubstituted Pyrroles and Pyridines.

An iodoxybenzoic acid-mediated selected oxidative cyclization of N-hydroxyalkyl enamines was developed. Through this strategy, a variety of 2,3-disubstituted pyrroles and pyridines were produced in good selectivity involving oxidation of alcohol, followed by condensation of aldehyde and α-C of enamines. Furthermore, this metal-free method has several advantages, including the use of environmentally friendly reagents, broad substrate scope, mild reaction conditions, and high efficiency.

Beta-Hydroxysteroid Dehydrogenase Genes in Orange-Spotted Grouper (Epinephelus coioides): Genome-Wide Identification and Expression Analysis During Sex Reversal.

Beta-hydroxysteroid dehydrogenases (ß-HSDs) are a group of steroidogenic enzymes that are involved in steroid biosynthesis and metabolism, and play a crucial role in mammalian physiology and development, including sex determination and differentiation. In the present study, a genome-wide analysis identified the numbers of ß-hsd genes in orange-spotted grouper (Epinephelus coioides) (19), human (Homo sapiens) (22), mouse (Mus musculus) (24), chicken (Gallus gallus) (16), xenopus (Xenopus tropicalis) (24), coelacanth (Latimeria chalumnae) (17), spotted gar (Lepisosteus oculatus) (14), zebrafish (Danio rerio) (19), fugu (Takifugu rubripes) (19), tilapia (Oreochromis niloticus) (19), medaka (Oryzias latipes) (19), stickleback (Gasterosteus aculeatus) (17) and common carp (Cyprinus carpio) (27) samples. A comparative analysis revealed that the number of ß-hsd genes in teleost fish was no greater than in tetrapods due to gene loss followed by a teleost-specific whole-genome duplication event. Based on transcriptome data from grouper brain and gonad samples during sex reversal, six ß-hsd genes had relatively high expression levels in the brain, indicating that these genes may be required for neurogenesis or the maintenance of specific biological processes in the brain. In the gonad, two and eight ß-hsd genes were up- and downregulated, respectively, indicating their important roles in sex reversal. Our results demonstrated that ß-hsd genes may be involved in the sex reversal of grouper by regulating the synthesis and metabolism of sex steroid hormones.

PfSMAD1/5 Can Interact with PfSMAD4 to Inhibit PfMSX to Regulate Shell Biomineralization in Pinctada fucata martensii.

The BMP2 signal transduced by SMAD1/5 plays an important role in osteoblast differentiation and bone formation. Shell formation of Pinctada fucata martensii is a typical biomineralization process that is similar to that of teeth/bone formation. However, whether the Pinctada fucata BMP2 (PfBMP2) signal transduced by PfSMAD1/5 occurs in P. f. martensii, how the PfBMP2 signal is transduced by PfSMAD1/5, and how PfSMAD1/5 regulates the biomineralization process in this species and other shellfish are poorly understood. Therefore, injection experiments of recombinant PfBMP2 and inhibitor dorsomorphin revealed that PfSMAD1/5 can transduce PfBMP2 signals. Subcellular localization and bimolecular fluorescence complementation assays indicated that PfSMAD1/5 phosphorylated by PfBMPR1b interacts with PfSMAD4 in the cytoplasm to form a complex, which translocates to the nucleus to transduce PfBMP2 signals. Co-immunoprecipitation and luciferase assays revealed that PfSMAD1/5 may interact with PfMSX to dislodge it from its binding element, resulting in initiation of mantle gene transcription. The in vivo functional assay showed that knockdown of PfMSAD1/5 decreased expression of shell matrix genes and disordered the nacreous layer, and the correlation assay of shell regeneration showed the concomitant expression pattern of PfSMAD1/5 and shell matrix genes. Together, these data showed that PfSMAD1/5 can transduce PfBMP2 signals to regulate shell biomineralization in P. f. martensii, which illustrated conservation of the BMP2-SMAD signal pathway among invertebrates. Particularly, the results suggest that there is only one PfMSX gene, which functions like the Hox gene in vertebrates, that interacts with PfSMAD1/5 in a protein-protein action form and plays the role of transcription repressor.

An estradiol-17ß/miRNA-26a/cyp19a1a regulatory feedback loop in the protogynous hermaphroditic fish, Epinephelus coioides.

Cyp19a1a is a key gene responsible for the production of estradiol-17ß (E2), the main functional estrogen and a major downstream regulator of reproduction in teleost fish. It is widely known that CYP19 gene expression, aromatase activity, and E2 production can influence gonadal differentiation and sex reversal in teleost fish, but the feedback mechanisms whereby E2 regulates cyp19a1a remain poorly understood, especially regarding the potential roles of endogenous small RNA molecules (miRNAs). Here, we identified miR-26a-5p as a regulatory factor of its predicted target gene (cyp19a1a). In vitro and in vivo studies showed that miR-26a-5p can decrease cyp19a1a expression. Furthermore, high doses of E2 act as a repressor of miR-26a-5p. This study proposes a regulatory feedback loop whereby E2 regulates cyp19a1a through miR-26a-5p, and suggests that this positive feedback is an important aspect of the control of E2 production.

Single-walled carbon nanotubes as delivery vehicles enhance the immunoprotective effect of an immersion DNA vaccine against infectious spleen and kidney necrosis virus in mandarin fish.

As a high mortality disease, Infectious spleen and kidney necrosis virus (ISKNV) can cause massive economic damage on mandarin fish farming industry in China, which seriously hindered the development of mandarin fish farming industry. In this research, SWCNTs (single-walled carbon nanotubes) as a candidate for DNA vaccine carrier was vaccinated by immersion (1, 2, 5, 10, 20 mg/L) in juvenile mandarin fish. In muscle, spleen and kidney tissues, the results showed that transcription and expression of MCP gene can be detected in pcDNA-MCP and SWCNTs-pcDNA-MCP groups after bath immunization. The immune response (immune-related genes expression, serum antibody production, enzyme activities and C3 content) was significantly enhanced in fish which vaccinated with SWCNTs-pcDNA-MCP in comparison with those vaccinated with pcDNA-MCP alone. After 14 d challenge, the RPS (relative percentage survival) can be enhanced which using SWCNTs as a carrier in SWCNTs-pcDNA-MCP (82.4%) group at 20 mg/L (the highest vaccine dose) than the naked pcDNA-MCP (54.2%) group. This study reveals that functionalized SWCNTs could be a promising immersion DNA vaccine carrier in aquaculture.

circFBXL5 promotes breast cancer progression by sponging miR-660.

Increasing studies have revealed that circular RNAs (circRNAs) play important roles in cancer progression. However, the potential involvement of circRNAs in breast cancer metastasis to lung is not clear so far. In this study, we conducted circular RNA microarrays of primary breast cancer tissues and lung metastatic tissues. The results revealed that circFBXL5 (hsa_circ_0125597) up-regulated the most in lung metastatic tissues. Survival analysis revealed that high levels of circFBXL5 correlated with worse outcome of breast cancer. Further experiments showed that knockdown of circFBXL5 inhibited breast cancer cell proliferation and migration to lung. Mechanism study showed that circFBXL5 acted as a sponge for miR-660 and compete binding to miR-660 with SRSF6, leading to increased expression of SRSF6. Collectively, our study highlighted the regulatory function of the circFBXL5/miR-660/SRSF6 pathway in breast cancer progression, which could be potential therapeutic targets for breast cancer.

MicroRNA-182-3p negatively regulates cytokines expression by targeting TLR5M in orange-spotted grouper, Epinephelus coioides.

Toll-like receptors (TLRs) as essential pattern recognition receptors in innate immunity, can recognize pathogens and trigger immune response to eliminate invading pathogens. MicroRNAs regulates multiple biological processes by suppressing mRNA translation or resulting in mRNA degradation. MiR-182 has previously been implicated in DNA repair, disease and cancer aspects. The potential role of miR-182-3p in TLR signaling pathway against pathogens is unclear. In this study, we found that the expression of miR-182-3p was up-regulated after Vibrio parahaemolyticus flagellin stimulation in grouper spleen (GS) cells, and negatively correlated with the expression of orange-spotted grouper (Epinephelus coioides) TLR5M (EcTLR5M). Then we found that miR-182-3p could directly target EcTLR5M by using bioinformatic analysis and dual-luciferase reporter assay. Dual-luciferase reporter assay also showed that miR-182-3p down-regulated the wild-type EcTLR5M 3'UTR in luciferase activity rather than the mutant group in HEK 293T cells. We further verified the effect of miR-182-3p on the activation of Nuclear factor-κB (NF-κB) signaling pathway, and found that miR-182-3p inhibitors significantly augmented flagellin-induced NF-κB phosphorylation. Additionally, we also demonstrated that the increased expression of miR-182-3p significantly suppressed the flagellin-induced EcTLR5M, pro-inflammatory cytokines interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) mRNA expression. And the endogenous miR-182-3p knockdown experiments reversely verified the regulatory effect of miR-182-3p. These results suggested that miR-182-3p post-transcriptionally controls EcTLR5M expression and thereby suppresses the expression of pro-inflammatory cytokines. This study is the first to demonstrate that miR-182-3p suppresses pro-inflammatory cytokines expression by regulating the TLR signaling pathway.