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Background: Sleep is critical in health problems including Parkinson's disease (PD). This study examined the association between sleep characteristics and the likelihood of prodromal PD. Methods: At baseline examination of the Heart and Brain Investigation in Taicang (HABIT) study, potential PD biomarkers were obtained for 8777 participants aged over 50 years, and the probability of prodromal PD was assessed based on the Chinese expert consensus and Movement Disorder Society (MDS) criteria. General and component sleep characteristics were evaluated by the Pittsburgh Sleep Quality Index (PSQI). Median regression was applied to examine the association between sleep and the probability of prodromal PD, adjusting for age, sex, education level, physical activity, obesity, fast plasma glucose, lipids, and hypertension. Results: Based on China criteria, a higher level of PSQI score was significantly associated with a higher probability of prodromal PD (ß = 0.02, 95% CI: 0.01-0.03) and a higher risk of having an increased probability of prodromal PD (OR = 1.04, 95% CI: 1.02-1.05). Compared to participants with good quality sleep, those with poor quality sleep had a 0.07% increased probability of prodromal PD (95% CI: 0.01-0.13) and a 19% increased risk of having a high prodromal PD probability (95% CI: 1.04-1.20). Similar associations between sleep quality and the probability of prodromal PD were also observed using the MDS criteria. Subjective sleep quality, sleep latency, habitual sleep efficiency, daytime dysfunction, and use of sleep medications were also associated with the probability of prodromal PD. Conclusion: Poor sleep quality was associated with a high probability of prodromal PD. Sleep may be helpful for understanding and intervention of prodromal PD.

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BACKGROUND AND AIMS: Human studies suggest that a high intake of polyunsaturated fatty acid (PUFA) is associated with an increased risk of inflammatory bowel disease (IBD). PUFA is highly prone to oxidation. To date, it is unclear whether unoxidized or oxidized PUFA is involved in the development of IBD. Here, we aim to compare the effects of unoxidized PUFA vs. oxidized PUFA on the development of IBD and associated colorectal cancer. METHODS: We evaluated the effects of unoxidized and oxidized PUFA on dextran sodium sulfate (DSS)- and IL-10 knockout-induced colitis, and azoxymethane (AOM)/DSS-induced colon tumorigenesis in mice. Additionally, we studied the roles of gut microbiota and Toll-like receptor 4 (TLR4) signaling involved. RESULTS: Administration of a diet containing oxidized PUFA, at human consumption-relevant levels, increases the severity of colitis and exacerbates the development of colitis-associated colon tumorigenesis in mice. Conversely, a diet rich in unoxidized PUFA doesn't promote colitis. Furthermore, oxidized PUFA worsens colitis-associated intestinal barrier dysfunction and leads to increased bacterial translocation, and it fails to promote colitis in Toll-like receptor 4 (TLR4) knockout mice. Finally, oxidized PUFA alters the diversity and composition of gut microbiota, and it fails to promote colitis in mice lacking the microbiota. CONCLUSIONS: These results support that oxidized PUFA promotes the development of colitis and associated tumorigenesis in mouse models via TLR4- and gut microbiota-dependent mechanisms. Our findings highlight the potential need to update regulation policies and industrial standards for oxidized PUFA levels in food.

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Catalytic conversion of lithium polysulfides (LiPSs) is a crucial approach to enhance the redox kinetics and suppress the shuttle effect in lithium-sulfur (Li-S) batteries. However, the roles of a typical heterogenous catalyst cannot be easily identified due to its structural complexity. Compared with the distinct sites of single atom catalysts (SACs), each active site of single site catalysts (SSCs) is identical and uniform in their spatial energy, binding mode, and coordination sphere, etc. Benefiting from the well-defined structure, iron phthalocyanine (FePc) is covalently clicked onto CuO nanosheet to prepare low spin-state Fe SSCs as the model catalyst for Li-S electrochemistry. The periodic polarizability evolution of Fe-N bonding is probed during sulfur redox reaction by in situ Raman spectra. Theoretical analysis shows the decreased d-band center gap of Fe (Δd) and delocalization of dxz/dyz after the axial click confinement. Consequently, Li-S batteries with Fe SSCs exhibit a capacity decay rate of 0.029% per cycle at 2 C. The universality of this methodological approach is demonstrated by a series of M SSCs (M = Mn, Co, and Ni) with similar variation of electronic configuration. This work provides guidance for the design of efficient electrocatalysis in Li-S batteries.

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Nonprecious metal catalysts, particularly M-N-C catalysts, are widely recognized as promising contenders for the oxygen reduction reaction (ORR). However, a notable performance gap persists between M-N-C catalysts and Pt-based catalysts under acidic conditions. In this study, hybrid catalysts comprising single Co atoms and ultralow concentrations of Pt3Co intermetallic nanoparticles (NPs) are introduced to enhance ORR performance. Under acidic conditions, these hybrid catalysts demonstrate ORR efficiency with a half-wave potential of 0.895 V, negligible decay even after 80 000 cycles, and a high maximum power density of 1.34 W cm-2 in fuel cells. This performance surpasses those of Co-N-C and Pt/Co-N-C catalysts. Both experimental findings and theoretical computations suggest that the heightened ORR activity stems from an increase in the spin density of Co sites induced by noble metal NPs, facilitating the activation of O-O bonds via side-on overlapping and enabling a transition in the reaction pathway from associative to dissociative processes. This research offers a promising avenue for the systematic design of M-N-C cathodes with an enhanced performance for acidic fuel cells.

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Resistance to cisplatin presents a major obstacle in managing advanced-stage cervical cancer. Cuproptosis, a newly identified form of cell death induced by copper ions, has potential in overcoming chemoresistance. But the application of cuproptosis in cervical cancer resistant to cisplatin has not yet been reported. In this study, treatment with Elsm-Cu in cervical cancer cells induced cuproptosis, affecting cell proliferation and apoptosis was found. Moreover, cuproptosis in cervical cancer cells was significantly induced by baicalein. The combination of baicalein and cisplatin exhibited a synergistic effect on cervical cancer cells by promoting apoptosis and inhibiting cell viability via the induction of cuproptosis. Animal experiments demonstrated that this combination significantly suppressed tumor growth. Upon treating cells with SC79 (Akt agonist), a significant inhibition of the expression of cuproptosis-related proteins SDHB and FDX1 were observed, indicating that baicalein induced cuproptosis through the Akt pathway. These results indicated that baicalein, mediated through the Akt pathway to induce cuproptosis, had the potential to improve the sensitivity of cervical cancer cells to cisplatin.

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The trail making test (TMT) is a commonly used tool for evaluating executive functions, and the activation of cerebral oxygenation in the prefrontal cortex (PFC) during the test can reflect the participation of executive function. This study aimed to compare the differences in cerebral oxygenation in the PFC between the computer- and paper-based versions of the TMT and provide a theoretical basis for the optimization and clinical application of the computer-based version. A total of 32 healthy adult participants completed the computer- and paper-based TMT Types A and B. Cerebral oxygenation changes in the PFC were monitored during the experiment using near-infrared spectroscopy. Moreover, average changes in oxyhemoglobin (Δoxy-Hb) levels at the baseline and during activation periods in different types of testing were compared and analyzed. The number of correct connections in the computer-based version Type B was less than that in the paper-based version Type B (p < .001). The task time of the computer-based version was longer than that of the paper-based version (p < .001). The B/A ratio of the number of correct connections in the computer-based version was lower than that in the paper-based version (p < .001). The Δoxy-Hb in the PFC of the paper-based version was higher than that of the computer-based version (p < .001). Significant differences in oxygenation in the PFC were observed between the paper- and computer-based versions of TMT. After further improvement and correction in the subsequent development of the computer-based TMT, and taking into account the psychological feelings and preferences of the participants when performing different versions of the TMTs, the computer-based TMT is expected to play a good auxiliary role in clinical evaluation.

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Osteogenesis imperfecta (OI) is a group of severe genetic bone disorders characterized by congenital low bone mass, deformity, and frequent fractures. Type XV OI is a moderate to severe form of skeletal dysplasia caused by WNT1 variants. In this cohort study from southern China, we summarized the clinical phenotypes of patients with WNT1 variants and found that the proportion of type XV patients was around 10.3% (25 out of 243) with a diverse spectrum of phenotypes. Functional assays indicated that variants of WNT1 significantly impaired its secretion and effective activity, leading to moderate to severe clinical manifestations, porous bone structure, and enhanced osteoclastic activities. Analysis of proteomic data from human skeleton indicated that the expression of SOST (sclerostin) was dramatically reduced in type XV patients compared to patients with COL1A1 quantitative variants. Single-cell transcriptome data generated from human tibia samples of patients diagnosed with type XV OI and leg-length discrepancy, respectively, revealed aberrant differentiation trajectories of skeletal progenitors and impaired maturation of osteocytes with loss of WNT1, resulting in excessive CXCL12+ progenitors, fewer mature osteocytes, and the existence of abnormal cell populations with adipogenic characteristics. The integration of multi-omics data from human skeleton delineates how WNT1 regulates the differentiation and maturation of skeletal progenitors, which will provide a new direction for the treatment strategy of type XV OI and relative low bone mass diseases such as early onset osteoporosis.

Osteogenesis imperfecta is a rare disease characterized by low bone mass, frequent fractures, and long bone deformity. Type XV osteogenesis imperfect is an autosomal recessive disorder caused by WNT1 variants, while heterozygous variants of WNT1 result in early onset osteoporosis. In this cohort study, we summarized the clinical features of 25 patients diagnosed with type XV osteogenesis imperfect. The WNT1 variants were confirmed by genetic test. Molecular assays were conducted to reveal the impact of variants on WNT1 protein activity and bone structure. We then compared the protein levels in bone tissues isolated from the type XV patients and patients with mild deformity using proteomic method, and found that the expression of SOST, mainly produced by mature osteoblasts and osteocytes, was dramatically reduced in type XV patients. We further compared the global mRNA expression levels in the skeletal cells using single-cell RNA sequencing. Analyses of these data indicated that more immature progenitors were identified and maturation of osteocytes was impaired with WNT1 loss-of-function. Our study helps to understand the underlying pathogenesis of type XV osteogenesis imperfecta.

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Background: NLP models like ChatGPT promise to revolutionize text-based content delivery, particularly in medicine. Yet, doubts remain about ChatGPT's ability to reliably support evaluations of cognitive performance, warranting further investigation into its accuracy and comprehensiveness in this area. Method: A cohort of 60 cognitively normal individuals and 30 stroke survivors underwent a comprehensive evaluation, covering memory, numerical processing, verbal fluency, and abstract thinking. Healthcare professionals and NLP models GPT-3.5 and GPT-4 conducted evaluations following established standards. Scores were compared, and efforts were made to refine scoring protocols and interaction methods to enhance ChatGPT's potential in these evaluations. Result: Within the cohort of healthy participants, the utilization of GPT-3.5 revealed significant disparities in memory evaluation compared to both physician-led assessments and those conducted utilizing GPT-4 (P < 0.001). Furthermore, within the domain of memory evaluation, GPT-3.5 exhibited discrepancies in 8 out of 21 specific measures when compared to assessments conducted by physicians (P < 0.05). Additionally, GPT-3.5 demonstrated statistically significant deviations from physician assessments in speech evaluation (P = 0.009). Among participants with a history of stroke, GPT-3.5 exhibited differences solely in verbal assessment compared to physician-led evaluations (P = 0.002). Notably, through the implementation of optimized scoring methodologies and refinement of interaction protocols, partial mitigation of these disparities was achieved. Conclusion: ChatGPT can produce evaluation outcomes comparable to traditional methods. Despite differences from physician evaluations, refinement of scoring algorithms and interaction protocols has improved alignment. ChatGPT performs well even in populations with specific conditions like stroke, suggesting its versatility. GPT-4 yields results closer to physician ratings, indicating potential for further enhancement. These findings highlight ChatGPT's importance as a supplementary tool, offering new avenues for information gathering in medical fields and guiding its ongoing development and application.

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Purpose: The purpose of this study is to summarize the design and methodology of a large-scale trial in northern China, the Beijing Angle Closure Progression Study (BAPS). This trial is designed to explore the 5-year incidence of primary angle-closure suspect (PACS) progressing to primary angle-closure (PAC) or primary angle-closure glaucoma (PACG) and to determine the possible risk factors of disease progression. Methods/design: The BAPS is a clinic-based, multicenter, noninterventional trial conducted on a sample of urban Chinese adults. Consecutive eligible patients who meet PACS diagnostic criteria will be recruited from eight participating centers, with the trial commencing on August 4, 2022. The target sample size is set at 825 subjects, with follow up planned for a minimum period of 5 years. Baseline examination will include presenting visual acuity, best corrected visual acuity, intraocular pressure (IOP), undilated slit-lamp biomicroscopy, stereoscopic evaluation of the optic disc, visual field test, optical coherence tomography evaluation of retinal nerve fiber layer, ultrasound biomicroscopy and IOLMaster. Questionnaires will also be used to collect detailed personal history. Patients are scheduled to visit the glaucoma clinic every 12 months and may visit the emergency room in case of acute attack of angle closure. Study endpoints include acute PAC episodes, elevated IOP, peripheral anterior synechiae, glaucomatous visual field defect, or glaucomatous abnormality of optic nerve. Discussion: The BAPS will provide data on the 5-year incidence of PACS progressing to PAC or PACG and determine the risk factors for disease progression. This study will also help redefine high-risk patients with PACS.

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BACKGROUND: Vascular health has been associated with cognition but related evidence is limited in Chinese. The objective of this study was to examine the association of vascular aging assessed by arterial stiffness and blood pressure with cognitive function in an unselected Chinese population. METHODS: In the Tianning Cohort (N = 5158), indicators of arterial stiffness and blood pressure including carotid-femoral pulse wave velocity (cfPWV), ankle-brachial index (ABI), pulse pressure (PP), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured. Cognitive function was assessed using the Mini Mental State Examination (MMSE) questionnaire. We applied Poisson regression and logistic regression to examine the associations of vascular aging and blood pressure with cognitive function. RESULTS: 76 (1.47%) participants had impaired cognitive function diagnosed by a MMSE score of less than 24 points. Participants with a higher level of PP were more likely to have a decreased score of MMSE (ß=-0.0121, P < 0.001 for log-transformed pulse pressure) and a higher risk of having impaired cognitive function (OR = 5.95, 95%CI: 2.02-17.79, P < 0.001 for log-transformed PP). Per standard deviation increment in SBP was significantly associated with lower MMSE score (ß=-0.0020, P < 0.001) and impaired cognitive function (OR = 1.69, 95%CI: 1.38-2.06, P < 0.001). No significant associations were found regarding other parameters. CONCLUSIONS: Blood pressure and hypertension were associated with cognitive function in Chinese adults. PP may be a potential predictor for impaired cognitive function.

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The importance of community-based non-communicable disease (NCD) management has been internationally recognized. However, currently, no instrument is available to evaluate a community's ability to provide NCD management for its residents. This study defined such an ability as "Community Efficacy for NCD Management" (COEN), and aimed to conceptualize, develop and validate a scale to measure COEN. We first conducted literature review, expert interviews, and Delphi panels to conceptualize COEN and select scale items. Then, we conducted two rounds of community surveys and interviews to validate the COEN scale among local residents in three cities in China. We used Cronbach's alpha to test the scale's internal consistency, Kappa test for test-retest reliability, and exploratory factor analysis for structural validity. COEN was conceptualized as "the ability of a community to provide NCD management for its residents, reflected by its natural environment, social relationships, community resources, health services, and resident-engaging activities." The first community research among 345 residents yielded a 38-item COEN scale with high internal consistency (Cronbach's alpha = 0.86) and acceptable test-retest reliability (Kappa value >0.2). The second community research tested a shortened COEN scale among 657 residents, yielding a final COEN scale with 14 items from five factors: community management (n = 3), social relationships (n = 4), resource accessibility (n = 3), community health services (n = 2), and resident engagement (n = 2), with an overall Cronbach's alpha of 0.79. COEN is a meaningful concept in contextualizing and evaluating NCD management anchored in the community, and the COEN scale is a multi-domain reliable tool to quantify COEN, which can be used to guide future related research and practice in public health.

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Ripretinib, a broad-spectrum inhibitor of the KIT and PDGFRA receptor tyrosine kinases, is designated as a fourth-line treatment for gastrointestinal stromal tumor (GIST). It is tailored for patients resistant to imatinib, sunitinib, and regorafenib. As its increasing use, instances of resistance to ripretinib are becoming more frequent. Unfortunately, there are currently no scientifically mature treatment options available for patients resistant to ripretinib. Posttranslational modifications (PTMs) such as ubiquitination, in conjunction with its interplay with other modifications, play a collective role in regulating tumor initiation and progression. However, the specific association between ubiquitination and ripretinib resistance is not reported. Through proteome-ubiquitinome sequencing, increased levels of the USP5 protein and decreased ubiquitination in ripretinib-resistant GISTs are detected. Subsequent examination of the mass spectrometry findings validated the interaction through which TRIM21 governs USP5 expression via ubiquitination, and USP5 regulates MDH2 expression through deubiquitination, consequently fostering ripretinib resistance in GIST. Moreover, ZDHHC18 can palmitoylate MDH2, preventing its ubiquitination and further increasing its protein stability. The research underscores the correlation between posttranslational modifications, specifically ubiquitination, and drug resistance, emphasizing the potential of targeting the USP5-MDH2 axis to counteract ripretinib resistance in GIST.

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Disentangling the limitations of O-O bond activation and OH* site-blocking effects on Pt sites is key to improving the intrinsic activity and stability of low-Pt catalysts for the oxygen reduction reaction (ORR). Herein, we integrate of PtFe alloy nanocrystals on a single-atom Fe-N-C substrate (PtFe@FeSAs-N-C) and further construct a ferromagnetic platform to investigate the regulation behavior of the spin occupancy state of the Pt d-orbital in the ORR. PtFe@FeSAs-N-C delivers a mass activity of 0.75 A mgPt-1 at 0.9 V and a peak power density of 1240 mW cm-2 in the fuel-cell, outperforming the commercial Pt/C catalyst, and a mass activity retention of 97%, with no noticeable current drop at 0.6 V for more than 220 h, is attained. Operando spectroelectrochemistry decodes the orbital interaction mechanism between the active center and reaction intermediates. The Pt dz2 orbital occupation state is regulated to t2g6eg3 by spin-charge injection, suppressing the OH* site-blocking effect and effectively inhibiting H2O2 production. This work provides valuable insights into designing high-performance and low-Pt catalysts via spintronics-level engineering.

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Epidural steroid injection for the treatment of sciatica caused by disc herniation is increasingly used worldwide, but its effectiveness remains controversial. The review aiming to analyze the efficacy of epidural steroid injection on sciatica caused by lumbar disc herniation. Randomized controlled trials (RCTs) investigating the use of epidural steroid injections in the management of sciatica induced by lumbar disc herniation were collected from PubMed and other databases from January, 2008 to December, 2023, with epidural steroid injection in the test group and epidural local anesthetic and/or placebo in the control group. Pain relief rate, assessed by numerical rating scale (NRS) and visual analogue scale (VAS) scores, and function recovery, evaluated by Roland Morris Disability Questionnaire (RMDQ) and Oswestry Disability Index (ODI) scores, were recorded and compared. Meta-analysis was performed by Review Manager. In comparison to the control group, epidural steroid injections have been shown to be effective for providing short- (within 3 months) [MD = 0.44, 95%CI (0.20, 0.68), p = 0.0003] and medium-term (within 6 months) [MD = 0.66, 95%CI (0.09,1.22), p = 0.02] pain relief for sciatica caused by lumbar disc herniation, while its long-term pain-relief effect were limited. However, the administration of epidural steroid injections did not lead to a significant improvement on sciatic nerve function in short- [MD = 0.79, 95%CI = (0.39, 1.98), p = 0.19] and long-term [MD = 0.47, 95% CI = (-0.86, 1.80), p = 0.49] assessed by IOD. Furthermore, the analysis revealed that administering epidural steroid injections resulted in a reduction in opioid usage among patients with lumbar disc herniation [MD = -14.45, 95% CI = (-24.61, -4.29), p = 0.005]. The incidence of epidural steroid injection was low. Epidural steroid injection has demonstrated notable efficacy in relieving sciatica caused by lumbar disc herniation in short to medium-term. Therefore, it is recommended as a viable treatment option for individuals suffering from sciatica.

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The present study focused on the degradation of sulfamethoxazole (SMX) aqueous solution and the toxicity of processing aqueous by the dielectric barrier discharge (DBD) activated persulfate (PS). The effects of input voltage, input frequency, duty cycle, and PS dosage ratio on the SMX degradation efficiency were measured. Based on the results of the Response Surface Methodology (RSM), SMX degradation efficiency reached 83.21% which is 10.54% higher than that without PS, and the kinetic constant was 0.067 min-1 in 30 min when the input voltage at 204 V (input power at 110.6 W), the input frequency at 186 Hz, the duty cycle at 63%, and the PS dosage ratio at 5.1:1. The addition of PS can produce more active particles reached 1.756 mg/L (O3), 0.118 mg/L (H2O2), 0.154 mmol/L (·OH) in 30 min. Furthermore, the DBD plasma system effectively activated an optimal amount of PS, leading to improved removal efficiency of COD, and TOC to 30.21% and 47.21%, respectively. Subsequently, eight primary by-products were pinpointed, alongside the observation of three distinct pathways of transformation. Predictions from the ECOSAR software indicated that most of the degradation intermediates were less toxic than SMX. The biological toxicity experiments elucidated that the treatment with the DBD/PS system effectively reduced the mortality of zebrafish larvae caused by SMX from 100% to 20.13% and improved the hatching rate from 55.69% to 80.86%. In particular, it is important to note that the degradation intermediates exhibit teratogenic effects on zebrafish larvae.

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For the 2D metal-free carbon catalysts, the atomic coplanar architecture enables a large number of pz orbitals to overlap laterally, thus forming π-electron delocalization, and the delocalization degree of the central atom dominates the catalytic activity. Herein, designing sulfur-doped defect-rich graphitic carbon nitride (S-Nv-C3N4) materials as a model, we propose a strategy to promote localized electron polarization by enhancing the ferromagnetism of ultra-thin 2D carbon nitride nanosheets. The introduction of sulfur (S) further promotes localized ferromagnetic coupling, thereby inducing long-range ferromagnetic ordering and accelerating the electron interface transport. Meanwhile, the hybridization of sulfur atoms breaks the symmetry and integrity of the unit structure, promotes electron enrichment and stimulating electron delocalization at the active site. This optimization enhances the *OOH desorption, providing a favorable kinetic pathway for the production of hydrogen peroxide (H2O2). Consequently, S-Nv-C3N4 exhibits high selectivity (>95 %) and achieves a superb H2O2 production rate, approaching 4374.8 ppm during continuous electrolysis over 300 hour. According to theoretical calculation and in situ spectroscopy, the ortho-S configuration can provide ferromagnetic perturbation in carbon active centers, leading to the electron delocalization, which optimizes the OOH* adsorption during the catalytic process.

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Congenital scoliosis (CS), affecting approximately 0.5 to 1 in 1,000 live births, is commonly caused by congenital vertebral malformations (CVMs) arising from aberrant somitogenesis or somite differentiation. While Wnt/ß-catenin signaling has been implicated in somite development, the function of Wnt/planar cell polarity (Wnt/PCP) signaling in this process remains unclear. Here, we investigated the role of Vangl1 and Vangl2 in vertebral development and found that their deletion causes vertebral anomalies resembling human CVMs. Analysis of exome sequencing data from multiethnic CS patients revealed a number of rare and deleterious variants in VANGL1 and VANGL2, many of which exhibited loss-of-function and dominant-negative effects. Zebrafish models confirmed the pathogenicity of these variants. Furthermore, we found that Vangl1 knock-in (p.R258H) mice exhibited vertebral malformations in a Vangl gene dose- and environment-dependent manner. Our findings highlight critical roles for PCP signaling in vertebral development and predisposition to CVMs in CS patients, providing insights into the molecular mechanisms underlying this disorder.

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The production of succinic acid from corn stover is a promising and sustainable route; however, during the pretreatment stage, byproducts such as organic acids, furan-based compounds, and phenolic compounds generated from corn stover inhibit the microbial fermentation process. Selecting strains that are resistant to stress and utilizing nondetoxified corn stover hydrolysate as a feedstock for succinic acid production could be effective. In this study, A. succinogenes CICC11014 was selected as the original strain, and the stress-resistant strain A. succinogenes M4 was obtained by atmospheric and room temperature plasma (ARTP) mutagenesis and further screening. Compared to the original strain, A. succinogenes M4 exhibited a twofold increase in stress resistance and a 113% increase in succinic acid production when hydrolysate was used as the substrate. By conducting whole-genome resequencing of A. succinogenes M4 and comparing it with the original strain, four nonsynonymous gene mutations and two upstream regions with base losses were identified. KEY POINTS: • A high-stress-resistant strain A. succinogenes M4 was obtained by ARTP mutation •  The production of succinic acid increased by 113% • The mutated genes of A. succinogenes M4 were detected and analyzed.

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Defects such as grain boundaries (GBs) are almost inevitable during the synthesis process of 2D materials. To take advantage of the fascinating properties of 2D materials, understanding the nature and impact of various GB structures on pristine 2D sheets is crucial. In this work, using an evolutionary algorithm search, we predict a wide variety of silicene GB structures with very different atomic structures compared with those found in graphene or hexagonal boron-nitride. Twenty-one GBs with the lowest energy were validated by density functional theory (DFT), a majority of which were previously unreported to our best knowledge. Based on the diversity of the GB predictions, we found that the formation energy and mechanical properties can be dramatically altered by adatom positions within a GB and certain types of atomic structures, such as four-atom rings. To study the mechanical behavior of these GBs, we apply strain to the GB structures stepwise and use DFT calculations to investigate the mechanical properties of 9 representative structures. It is observed that GB structures based on pentagon-heptagon pairs are likely to have similar or higher in-plane stiffness and strength compared to the zigzag orientation of pristine silicene. However, an adatom located at the hollow site of a heptagon ring can significantly deteriorate the mechanical strength. For all of the structures, the in-plane stiffness and strength were found to decrease with increasing formation energy. For the failure behavior of GB structures, it was found that GB structures based on pentagon-heptagon pairs have failure behavior similar to that of graphene. We also found that the GB structures with atoms positioned outside of the 2D plane tend to experience phase transitions before failure. Utilizing the evolutionary algorithm, we locate diverse silicene GBs and obtain useful information about their mechanical properties.

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The combination of surface coils and metamaterials remarkably enhance magnetic resonance imaging (MRI) performance for significant local staging flexibility. However, due to the coupling in between, impeded signal-to-noise ratio (SNR) and low-contrast resolution, further hamper the future growth in clinical MRI. In this paper, we propose a high-Q metasurface decoupling isolator fueled by topological LC loops for 1.5T surface coil MRI system, increasing the magnetic field up to fivefold at 63.8 MHz. We have employed a polarization conversion mechanism to effectively eliminate the coupling between the MRI metamaterial and the radio frequency (RF) surface transmitter-receiver coils. Furthermore, a high-Q metasurface isolator was achieved by taking advantage of bound states in the continuum (BIC) for extremely high-resolution MRI and spectroscopy. An equivalent physical model of the miniaturized metasurface design was put forward through LC circuit analysis. This study opens up a promising route for the easy-to-use and portable surface coil MRI scanners.