Role of rumination and hope on negative life events and suicidal ideation under the background of normalization of pandemic prevention and control: A moderated mediation model

IntroductionThe study aimed to investigate the impact and mechanism of negative life events on college students' suicidal ideation during the COVID-19 pandemic and the buffering effect of hope under the background of normalization of pandemic.MethodsA total of 5211 participants took part in this study. Self-reported negative life events, rumination, hope and suicide ideation were measured using a range of questions and scales. Our research demonstrated that the incidence of suicidal ideation among college freshmen in the past week was higher during the COVID-19 pandemic than that before the pandemic. In this study, conditional process model 15 was used to verify the hypothetical model of rumination as a potential mediator and hope as a moderator.ResultsThe hypothesized moderated mediation model was verified significant (β = -0.047, 95% CI = [-0.061, -0.035]), and hope was found to moderate the direct effect of negative life events on suicidal ideation (β = -0.039, t = -2.937, 95% CI = [-0.065, -0.013]) as well as the indirect effect of through the mediator rumination (β = -0.134, t = -10.850, 95% CI = [-0.158, -0.110]).DiscussionWe found that rumination partially mediated the effect of negative life events on suicidal ideation, and hope buffered the direct and indirect effect of negative life events on suicidal ideation. The implications of the findings for clinical interventions are discussed, including the importance of hope arousal as a protective factor and rumination as a cognitive mechanism for emotion regulation under the background of normalization of pandemic

Effects of Phase-Locking Deficits on Speech Recognition in Older Adults With Presbycusis

Objective: People with presbycusis (PC) often report difficulties in speech recognition, especially under noisy listening conditions. Investigating the PC-related changes in central representations of envelope signals and temporal fine structure (TFS) signals of speech sounds is critical for understanding the mechanism underlying the PC-related deficit in speech recognition. Frequency-following responses (FFRs) to speech stimulation can be used to examine the subcortical encoding of both envelope and TFS speech signals. This study compared FFRs to speech signals between listeners with PC and those with clinically normal hearing (NH) under either quiet or noise-masking conditions.Methods: FFRs to a 170-ms speech syllable /da/ were recorded under either a quiet or noise-masking (with a signal-to-noise ratio (SNR) of 8 dB) condition in 14 older adults with PC and 13 age-matched adults with NH. The envelope (FFRENV) and TFS (FFRTFS) components of FFRs were analyzed separately by adding and subtracting the alternative polarity responses, respectively. Speech recognition in noise was evaluated in each participant.Results: In the quiet condition, compared with the NH group, the PC group exhibited smaller F0 and H3 amplitudes and decreased stimulus-response (S-R) correlation for FFRENV but not for FFRTFS. Both the H2 and H3 amplitudes and the S-R correlation of FFRENV significantly decreased in the noise condition compared with the quiet condition in the NH group but not in the PC group. Moreover, the degree of hearing loss was correlated with noise-induced changes in FFRTFS morphology. Furthermore, the speech-in-noise (SIN) threshold was negatively correlated with the noise-induced change in H2 (for FFRENV) and the S-R correlation for FFRENV in the quiet condition.Conclusion: Audibility affects the subcortical encoding of both envelope and TFS in PC patients. The impaired ability to adjust the balance between the envelope and TFS in the noise condition may be part of the mechanism underlying PC-related deficits in speech recognition in noise. FFRs can predict SIN perception performance

Biodiversity and phylogenetic analysis of the gut microbiome of Euphausia superba Dana from the Rose Sea of the Antarctic Ocean

Metabolites derived from marine symbiotic microorganisms have great potential as lead compounds for the discovery of novel marine drugs. Euphausia superba Dana, which lives in the Antarctic Ocean, is regarded as a new source of marine microbial natural products. However, no studies have examined the biodiversity of the symbiotic intestinal microbiome of E. superba. To address this issue, the species diversity and abundance of the gut microbiome of E. superba Dana from the Rose Sea of the Antarctic Ocean were analyzed by culture-independent high-throughput sequencing and pure culture methods. A comparison with gene databases revealed that the microbiome contained 61 known microbial species and a plethora of uncultivable microorganisms. Additionally, 7% of the species in the microbiome were currently unknown. The microbes belonged to 56 genera, eight of which, including Arthrobacter, Bacillus, Candidatus, Lactococcus, Lysinibacillus, Leuconostoc, Solibacillus, and Vibrio, were dominant, as were Vibrionaceae spp. Moreover, 81 microbial strains were isolated by the pure culture method, and they belonged to 36 genera, including Mobilicoccus, Rhodococcus, Arthrobacter, and Microbacterium. The results obtained by two different methods demonstrate the richness of the microbial biodiversity of the gut microbiome of E. superba, and it also suggests that they have good potential for the discovery of novel marine microbial species

Observation of electronic nematicity driven by three-dimensional charge density wave in kagome lattice KV3_3Sb5_5

Kagome superconductors AV$_3$Sb$_5$ (A = K, Rb, Cs) provide a fertile playground for studying various intriguing phenomena such as non-trivial band topology, superconductivity, giant anomalous Hall effect, and charge density wave (CDW). Remarkably, the recent discovery of $C_2$ symmetric nematic phase prior to the superconducting state in AV$_3$Sb$_5$ has drawn enormous attention, as the unusual superconductivity might inherit the symmetry of the nematic phase. Although many efforts have been devoted to resolve the charge orders using real-space microscopy and transport measurements, the direct evidence on the rotation symmetry breaking of the electronic structure in the CDW state from the reciprocal space is still rare. The underlying mechanism is still ambiguous. Here, utilizing the micron-scale spatially resolved angle-resolved photoemission spectroscopy, we observed the fingerprint of band folding in the CDW phase of KV$_3$Sb$_5$, which yet demonstrates the unconventional unidirectionality, and is indicative of the rotation symmetry breaking from $C_6$ to $C_2$. We then pinpointed that the interlayer coupling between adjacent planes with $\pi$-phase offset in the 2$\times$2$\times$2 CDW phase would lead to the preferred twofold symmetric electronic structure. Time-reversal symmetry is further broken at temperatures below $\sim$ 40 K as characterized by giant anomalous Hall effect triggered by weak magnetic fields. These rarely observed unidirectional back-folded bands with time-reversal symmetry breaking in KV$_3$Sb$_5$ may provide important insights into its peculiar charge order and superconductivity

Advances in anti-tumor based on various anaerobic bacteria and their derivatives as drug vehicles

Cancer therapies, such as chemotherapy and radiotherapy, are often unsatisfactory due to several limitations, including drug resistance, inability to cross biological barriers, and toxic side effects on the body. These drawbacks underscore the need for alternative treatments that can overcome these challenges and provide more effective and safer options for cancer patients. In recent years, the use of live bacteria, engineered bacteria, or bacterial derivatives to deliver antitumor drugs to specific tumor sites for controlled release has emerged as a promising therapeutic tool. This approach offers several advantages over traditional cancer therapies, including targeted drug delivery and reduced toxicity to healthy tissues. Ongoing research in this field holds great potential for further developing more efficient and personalized cancer therapies, such as E. coli, Salmonella, Listeria, and bacterial derivatives like outer membrane vesicles (OMVs), which can serve as vehicles for drugs, therapeutic proteins, or antigens. In this review, we describe the advances, challenges, and future directions of research on using live bacteria or OMVs as carriers or components derived from bacteria of delivery systems for cancer therapy

Gut Symbionts alleviate Mash Through a Secondary Bile acid Biosynthetic Pathway

The gut microbiota has been found to play an important role in the progression of metabolic dysfunction-associated steatohepatitis (MASH), but the mechanisms have not been established. Here, by developing a click-chemistry-based enrichment strategy, we identified several microbial-derived bile acids, including the previously uncharacterized 3-succinylated cholic acid (3-sucCA), which is negatively correlated with liver damage in patients with liver-tissue-biopsy-proven metabolic dysfunction-associated fatty liver disease (MAFLD). By screening human bacterial isolates, we identified Bacteroides uniformis strains as effective producers of 3-sucCA both in vitro and in vivo. By activity-based protein purification and identification, we identified an enzyme annotated as β-lactamase in B. uniformis responsible for 3-sucCA biosynthesis. Furthermore, we found that 3-sucCA is a lumen-restricted metabolite and alleviates MASH by promoting the growth of Akkermansia muciniphila. together, our data offer new insights into the gut microbiota-liver axis that may be leveraged to augment the management of MASH

Records of East Asian monsoon activities in Northeastern China since 15.6 ka, based on grain size analysis of peaty sediments in the Changbai Mountains

Peatlands provide a widespread terrestrial archive for Holocene study. However, little is known about the grain-size characteristics of peaty sediments and their environmental significance. In order to study these phenomena in detail, two sections from the Hani and Gushantun peatlands in the Changbai Mountain Area were cored and sub-sampled. Based on reliable calibrated AMS 14C ages, we established grain size variations in the peat cores since 15.6 ka cal. BP. Our results showed that the peaty sediments in the Changbai Mountains are mainly composed of silt. Moreover, the grain size component, which is related to paleoclimate variables, can be classified into three groups based on the “Grain size class vs. standard deviation” method. These sensitive grain size components are <37.0 mm (Component 1 or C1), 37.0e497.8 mm (Component 2 or C2) and >497.8 mm (Component 3 or C3). C1 comprises the finest silt in the peaty sediment and is mainly conveyed by the East Asian winter monsoon (EAWM), whereas C2 is transported into the peatland by surface runoff related to the enhancement of the East Asian summer monsoon (EASM). C3 is conveyed in saltation and bed-load mode by strong surface runoff linked to highenergy flow caused by a strong EASM, and perhaps is an indicator of extreme rainfall events in the Changbai Mountains. Our results suggest that the study region was dominated by a cold/dry environment during the late-glacial period under a strong EAWM. However, there was a marked climatic shift from an EAWM-dominated cold/dry climate to an EASM-dominated more mesic environment during the early Holocene. Increased percentage of C2 in peat cores during the Holocene Optimum (9.0e4.5 ka) indicates abundant rainfall in the study region (even with extreme rainfall events) as a result of a significant enhancement of the EASM. Weak monsoon events occurred at 10.5 ka, 9.2 ka, 8.2 ka, 7.2 ka, 6.2ka, 5.5 ka and 4.2 ka shown by sharp decreases in C2, agreeing with the stalagmite d18O records in China. The results obtained from environmentally sensitive grain-size component records are largely consistent with other palaeoenvironmental records in the East Asian monsoon area, substantiating the regional climate patterns and monsoon evolution since late-glacial time. Because intensity of the East Asian monsoon is likely responsible for the grain-size change in the peat samples, the grain size components in peat samples may be used for reconstructions of past environmental conditions and of variability in the East Asian monsoon

Intestinal segment and vitamin D3 concentration affect gene expression levels of calcium and phosphorus transporters in broiler chickens

Two experiments were conducted in this research. Experiment 1 investigated the spatial expression characteristics of calcium (Ca) and phosphorus (P) transporters in the duodenum, jejunum, and ileum of 21-day-old broilers provided with adequate nutrient feed. Experiment 2 evaluated the effects of dietary vitamin D3 (VD3) concentration (0, 125, 250, 500, 1,000, and 2,000 IU/kg) on growth performance, bone development, and gene expression levels of intestinal Ca and P transporters in 1–21-day-old broilers provided with the negative control diet without supplemental VD3. Results in experiment 1 showed that the mRNA levels of calcium-binding protein 28-kDa (CaBP-D28k), sodium-calcium exchanger 1 (NCX1), plasma membrane calcium ATPase 1b (PMCA1b), and IIb sodium-phosphate cotransporter (NaPi-IIb) were the highest in the broiler duodenum. By contrast, the mRNA levels of inorganic phosphate transporter 1 (PiT-1) and 2 (PiT-2) were the highest in the ileum. Results in experiment 2 showed that adding 125 IU/kg VD3 increased body weight gain (BWG), feed intake (FI), bone weight, and percentage and weight of Ca and P in the tibia and femur of 1–21-day-old broilers compared with the negative control diet (p &lt; 0.05). The rise in dietary VD3 levels from 125 to 1,000 IU/kg further increased the BWG, FI, and weights of the bone, ash, Ca, and P (p &lt; 0.05). No difference in growth rate and leg bone quality was noted in the broilers provided with 1,000 and 2,000 IU/kg VD3 (p &gt; 0.05). Supplementation with 125–2,000 IU/kg VD3 increased the mRNA abundances of intestinal Ca and P transporters to varying degrees. The mRNA level of CaBP-D28k increased by 536, 1,161, and 28 folds in the duodenum, jejunum, and ileum, respectively, after adding 1,000 IU/kg VD3. The mRNA levels of other Ca and P transporters (PMCA1b, NCX1, NaPi-IIb, PiT-1, and PiT-2) increased by 0.57–1.74 folds by adding 1,000–2,000 IU/kg VD3. These data suggest that intestinal Ca and P transporters are mainly expressed in the duodenum of broilers. Moreover, the addition of VD3 stimulates the two mineral transporter transcription in broiler intestines