Gold-Template-Assisted Mechanical Exfoliation of Large-Area 2D Layers Enables Efficient and Precise Construction of Moiré Superlattices.

Moiré superlattices, consisting of rotationally aligned 2D atomically thin layers, provide a highly novel platform for the study of correlated quantum phenomena. However, reliable and efficient construction of moiré superlattices is challenging because of difficulties to accurately angle-align small exfoliated 2D layers and the need to shun wet-transfer processes. Here, efficient and precise construction of various moiré superlattices is demonstrated by picking up and stacking large-area 2D mono- or few-layer crystals with predetermined crystal axes, made possible by a gold-template-assisted mechanical exfoliation method. The exfoliated 2D layers are semiconductors, superconductors, or magnets and their high quality is confirmed by photoluminescence and Raman spectra and by electrical transport measurements of fabricated field-effect transistors and Hall devices. Twisted homobilayers with angle-twisting accuracy of ≈0.3°, twisted heterobilayers with sub-degree angle-alignment accuracy, and multilayer superlattices are precisely constructed and characterized by their moiré patterns, interlayer excitons, and second harmonic generation. The present study paves the way for exploring emergent phenomena in moiré superlattices.

Early-life house dust mite aeroallergen exposure augments cigarette smoke-induced myeloid inflammation and emphysema in mice.

BACKGROUND: Longitudinal studies have identified childhood asthma as a risk factor for obstructive pulmonary disease (COPD) and asthma-COPD overlap (ACO) where persistent airflow limitation can develop more aggressively. However, a causal link between childhood asthma and COPD/ACO remains to be established. Our study aimed to model the natural history of childhood asthma and COPD and to investigate the cellular/molecular mechanisms that drive disease progression. METHODS: Allergic airways disease was established in three-week-old young C57BL/6 mice using house dust mite (HDM) extract. Mice were subsequently exposed to cigarette smoke (CS) and HDM for 8 weeks. Airspace enlargement (emphysema) was measured by the mean linear intercept method. Flow cytometry was utilised to phenotype lung immune cells. Bulk RNA-sequencing was performed on lung tissue. Volatile organic compounds (VOCs) in bronchoalveolar lavage-fluid were analysed to screen for disease-specific biomarkers. RESULTS: Chronic CS exposure induced emphysema that was significantly augmented by HDM challenge. Increased emphysematous changes were associated with more abundant immune cell lung infiltration consisting of neutrophils, interstitial macrophages, eosinophils and lymphocytes. Transcriptomic analyses identified a gene signature where disease-specific changes induced by HDM or CS alone were conserved in the HDM-CS group, and further revealed an enrichment of Mmp12, Il33 and Il13, and gene expression consistent with greater expansion of alternatively activated macrophages. VOC analysis also identified four compounds increased by CS exposure that were paradoxically reduced in the HDM-CS group. CONCLUSIONS: Early-life allergic airways disease worsened emphysematous lung pathology in CS-exposed mice and markedly alters the lung transcriptome.

Hybrid-Driven Origami Gripper with Variable Stiffness and Finger Length.

Soft grippers due to their highly compliant material and self-adaptive structures attract more attention to safe and versatile grasping tasks compared to traditional rigid grippers. However, those flexible characteristics limit the strength and the manipulation capacity of soft grippers. In this paper, we introduce a hybrid-driven gripper design utilizing origami finger structures, to offer adjustable finger stiffness and variable grasping range. This gripper is actuated via pneumatic and cables, which allows the origami structure to be controlled precisely for contraction and extension, thus achieving different finger lengths and stiffness by adjusting the cable lengths and the input pressure. A kinematic model of the origami finger is further developed, enabling precise control of its bending angle for effective grasping of diverse objects and facilitating in-hand manipulation. Our proposed design method enriches the field of soft grippers, offering a simple yet effective approach to achieve safe, powerful, and highly adaptive grasping and in-hand manipulation capabilities.

Machine learning methods predict recurrence of pN3b gastric cancer after radical resection.

Background: The incidence of stage pN3b gastric cancer (GC) is low, and the clinical prognosis is poor, with a high rate of postoperative recurrence. Machine learning (ML) methods can predict the recurrence of GC after surgery. However, the prognostic significance for pN3b remains unclear. Therefore, we aimed to predict the recurrence of pN3b through ML models. Methods: This retrospective study included 336 patients with pN3b GC who underwent radical surgery. A 3-fold cross-validation was used to partition the participants into training and test cohorts. Linear combinations of new variable features were constructed using principal component analysis (PCA). Various ML algorithms, including random forest, support vector machine (SVM), logistic regression, multilayer perceptron (MLP), extreme gradient boosting (XGBoost), and Gaussian naive Bayes (GNB), were utilized to establish a recurrence prediction model. Model performance was evaluated using the receiver operating characteristic (ROC) curve and the area under the curve (AUC). Python was used for the analysis of ML algorithms. Results: Nine principal components with a cumulative variance interpretation rate of 90.71% were identified. The output results of the test set showed that random forests had the highest AUC (0.927) for predicting overall recurrence with an accuracy rate of 80.5%. Random forests had the highest AUC (0.940) for predicting regional recurrence with an accuracy of 89.7%. For predicting distant recurrence, random forests had the highest AUC (0.896) with an accuracy of 84.3%. For peritoneal recurrence, random forests had the highest AUC (0.923) with an accuracy of 83.3%. Conclusions: ML can personalize the prediction of postoperative recurrence in patients with GC with stage pN3b.

Adjuvant Transarterial Chemoembolization Plus Immunotherapy for Huge Hepatocellular Carcinoma: A Propensity Score Matching Cohort Study.

Purpose: The prognosis of patients with huge hepatocellular carcinoma (huge HCC, diameter ≥10 cm) is poor owing to the high early recurrence rate. This study aimed to explore the clinical value of postoperative adjuvant transarterial chemoembolization (PA-TACE) plus programmed cell death-1 (PD-1) inhibitors for huge HCC. Patients and Methods: Data from consecutive huge HCC patients treated with hepatectomy during June 2017 and July 2022 were retrospectively collected. Baseline differences were balanced between huge HCC patients who underwent PA-TACE with (AIT group) or without PD-1 inhibitors (AT group) by propensity-score matching (PSM). We compared recurrence-free survival (RFS), overall survival (OS) and recurrence patterns between the two groups. Independent risk factors for RFS and OS were confirmed by Cox regression analysis, and subgroup analysis was also conducted. Results: A total of 294 patients were enrolled, and 77 pairs of patients in the AIT and AT groups were matched by PSM. The 1-year and 2-year RFS were 49.9% and 35.7% in the AIT group compared to 24.7% and 15.5% in the AT group respectively (p<0.001). The 1-year and 2-year OS were 83.6% and 66.9% in the AIT group compared to 50.6% and 36.8% in the AT group respectively (p<0.001). There were no significant differences in recurrence patterns between the two groups. Multivariable analysis demonstrated that combined therapy of PA-TACE plus PD-1 inhibitors was a protective factor related to both RFS and OS. Conclusion: PA-TACE plus PD-1 inhibitors could improve survival outcomes for huge HCC patients.

Time-averaged atomic volume spectrum: locating and identifying vacancies.

Vacancies, as well as their derivatives, usually play a crucial role in many essential properties of materials. However, they always behave erratically, especially under universal thermal vibration, and are therefore difficult to accurately locate. Until now, the lack of an accurate and flexible method for locating and identifying vacancies has hampered the development of relative fields. In this paper, we present a new method to solve this problem. The strategy is to target the atomic cage enwrapping vacancies instead of the vacancies themselves. The core of the method is a time-averaged atomic volume spectrum (TAVS). The key to this method is to identify atoms using time-averaged rather than transient atomic volume, thereby simultaneously denoising intrinsic thermal vibration and avoiding vacancy migration jump. Using this method, we have succeeded for the first time in obtaining the panoramic maps of spontaneously trapped defects in quenched and annealed face-centered cubic aluminum and even the instantaneous images of a steady trapping process. All characteristics of each trapped vacancy, including location, dimension, volume and morphology, as well as aggregate statistical data such as vacancy amount and concentration, can be completely and accurately obtained. Furthermore, these first maps of defects (vacancies) revealed some surprising and interesting phenomena for future exploration. In conclusion, this method provides not only a means of locating and catching vacancies, but also a strategy for identifying and characterizing vacancies. On the basis of its successful application in FCC Al, the TAVS method can be easily extended to other systems as well.

Associations of apolipoprotein E ε4 allele, regional cerebral blood flow, and serum liver function markers in patients with cognitive impairment.

Introduction: The ε4 allele of the apolipoprotein E gene (APOE4) is expressed abundantly in both the brain and peripheral circulation as a genetic risk factor for Alzheimer's disease (AD). Cerebral blood flow (CBF) dysfunction is an essential feature of AD, and the liver plays an important role in the pathogenesis of dementia. However, the associations of APOE4 with CBF and liver function markers in patients with cognitive impairment remains unclear. We aimed to evaluate the associations of APOE4 with CBF measured by arterial spin labeling (ASL) magnetic resonance imaging (MRI) and serum liver function markers in participants who were diagnosed with cognitive impairment. Methods: Fourteen participants with AD and sixteen with amnestic mild cognitive impairment (MCI) were recruited. In addition to providing comprehensive clinical information, all patients underwent laboratory tests and MRI. All participants were divided into carriers and noncarriers of the ε4 allele, and T-tests and Mann-Whitney U tests were used to observe the differences between APOE4 carriers and noncarriers in CBF and liver function markers. Results: Regarding regional cerebral blood flow (rCBF), APOE4 carriers showed hyperperfusion in the bilateral occipital cortex, bilateral thalamus, and left precuneus and hypoperfusion in the right lateral temporal cortex when compared with noncarriers. Regarding serum liver function markers, bilirubin levels (including total, direct, and indirect) were lower in APOE4 carriers than in noncarriers. Conclusion: APOE4 exerts a strong effect on CBF dysfunction by inheritance, representing a risk factor for AD. APOE4 may be related to bilirubin metabolism, potentially providing specific neural targets for the diagnosis and treatment of AD.

Association Between Frequency of Muscle-Strengthening Exercise and Depression Symptoms Among Middle and High School Students: Cross-Sectional Survey Study.

BACKGROUND: Existing literature on the association between the frequency of muscle-strengthening exercise (MSE) and depression among adolescents is limited and contradictory. OBJECTIVE: This study aimed to elucidate the association of MSE frequency with depression symptoms among middle and high school students in China. METHODS: A total of 27,070 students in grades 7-12 from 376 middle and high schools were surveyed using an anonymous self-administered questionnaire between April and June 2022. Information on engaging in MSE was self-reported, and depression symptoms were assessed using the Patient Health Questionnaire-9 (PHQ-9). Poisson regression was used to examine the association between MSE frequency and depression symptoms. RESULTS: Among the 27,006 eligible students, 51.6% (n=13,933) were boys, and the mean age was 15.6 (SD 1.7) years. The overall prevalence of meeting MSE recommendations (ie, engaging in MSE ≥3 days/week) was 34.6% (95% CI 32.6%-36.6%; n=9145); the prevalence was higher in boys (43.8%, 95% CI 41.8%-45.8%; 6067/13,933) than in girls (24.3%, 95% CI 22%-26.6%; 3078/13,073; P<.001). A total of 5882 (21.8%) students reported having depression symptoms. After adjustment for sociodemographic status, lifestyle factors, academic performance, and experience of physical fighting, compared to students who did not engage in MSE, the prevalence ratios (PRs) for depression symptoms were 0.98 (95% CI 0.97-0.99) for those engaging in MSE once a week, 0.95 (95% CI 0.93-0.97) for 2 days/week, 0.93 (95% CI 0.90-0.96) for 3 days/week, 0.90 (95% CI 0.87-0.94) for 4 days/week, 0.88 (95% CI 0.84-0.93) for 5 days/week, 0.86 (95% CI 0.81-0.92) for 6 days/week, and 0.84 (95% CI 0.78-0.90) for 7 days/week, respectively. CONCLUSIONS: The overall prevalence of meeting MSE recommendations among Chinese adolescents is low. The frequency of MSE was inversely associated with depression symptoms.

The effect of statins on the risk of anti-tuberculosis drug-induced liver injury among patients with active tuberculosis: A cohort study.

BACKGROUND: Tuberculosis (TB) remains prevalent worldwide, and anti-TB drugs are associated with drug-induced liver injury (DILI). Statins have pleiotropic effects which may decrease inflammation and achieve immunomodulation. However, few studies have investigated the pleiotropic effects of statins on the risk of DILI. The purpose of this study was to investigate whether statins prevent anti-tuberculosis DILI among active TB patients on standard anti-TB drug therapy. METHODS: We conducted a hospital-based retrospective cohort study using claims data from the Integrated Medical Database of National Taiwan University Hospital (NTUH-iMD). Patients with a positive TB culture were included. The use of statins was defined as a daily equivalent dose >0.5 mg of pitavastatin. Deterioration in liver function was evaluated according to elevated liver enzyme levels. The primary and secondary endpoints were the DILI and the severe DILI. The prognostic value of statins was evaluated by Kaplan-Meier analysis, and Cox proportional hazards models. RESULTS: A total of 1312 patients with a diagnosis of TB and receiving anti-TB treatment were included. During the study period, 193 patients had the DILI and 140 patients had the severe DILI. Kaplan-Meier analysis showed a significant difference between the usual statin users and controls in the DILI. In multivariable Cox proportional hazards analysis, statins showed a protective effect against the primary and secondary endpoints. In addition, the protective effect of statins showed a dose-response relationship against the DILI. CONCLUSION: Statin treatment had a protective effect against the risk of anti-TB DILI with a positive dose-response relationship.

Ursolic acid molecules dock MAPK1 to modulate gut microbiota diversity to reduce neuropathic pain.

To investigate the efficacy of Ursolic acid in alleviating neuropathic pain in rats with spinal nerve ligation (SNL), the SNL rat model was surgically induced. Different concentrations of Ursolic acid and manipulated target mitogen-activated protein kinase 1 (MAPK1) were administered to the SNL rats. Fecal samples were collected from each group of rats for 16S rDNA analysis to examine the impact of gut microbiota. Molecular docking experiments were conducted to assess the binding energy between Ursolic acid and MAPK1. In vivo studies were carried out to evaluate the expression of inflammatory factors and signaling pathways in spinal cord and colon tissues. Ursolic acid was found to have a beneficial effect on pain reduction in rats by increasing plantar withdrawal latency (PWL) and paw withdrawal threshold (PWT). Comparing the Ursolic acid group with the control group revealed notable differences in the distribution of Staphylococcus, Allobaculum, Clostridium, Blautia, Bifidobacterium, and Prevotella species. Network pharmacology analysis identified MAPK1 and intercellular adhesion molecule-1 (ICAM1) as common targets for Ursolic acid, SNL, and neuropathic pain. Binding sites between Ursolic acid and these targets were identified. Additionally, immunofluorescent staining showed a decrease in GFAP and IBA1 intensity in the spinal cord along with an increase in NeuN following Ursolic acid treatment. Overexpression of MAPK1 in SNL rats led to an increase in inflammatory factors and a decrease in PWL and PWT. Furthermore, MAPK1 counteracted the pain-relieving effects of Ursolic acid in SNL rats. Ursolic acid was found to alleviate neuropathic pain in SNL rats by targeting MAPK1 and influencing gut microbiota homeostasis.

DBH-YOLO: a surgical instrument detection method based on feature separation in laparoscopic surgery.

PURPOSE: Accurately locating and analysing surgical instruments in laparoscopic surgical videos can assist doctors in postoperative quality assessment. This can provide patients with more scientific and rational solutions for healing surgical complications. Therefore, we propose an end-to-end algorithm for the detection of surgical instruments. METHODS: Dual-Branched Head (DBH) and Overall Intersection over Union Loss (OIoU Loss) are introduced to solve the problem of inaccurate surgical instrument detection, both in terms of localization and classification. An effective method (DBHYOLO) for the detection for laparoscopic surgery in complex scenarios is proposed. This study manually annotates a new laparoscopic gastric cancer resection surgical instrument location dataset LGIL, which provides a better validation platform for surgical instrument detection methods. RESULTS: The proposed method's performance was tested using the m2cai16-tool-locations, LGIL, and Onyeogulu datasets. The mean Average Precision (mAP) values obtained were 96.8%, 95.6%, and 98.4%, respectively, which were higher than the other classical models compared. The improved model is more effective than the benchmark network in distinguishing between surgical instrument classes with high similarity and avoiding too many missed detection cases. CONCLUSIONS: In this paper, the problem of inaccurate detection of surgical instruments is addressed from two different perspectives: classification and localization. And the experimental results on three representative datasets verify the performance of DBH-YOLO. It is shown that this method has a good generalization capability.

Effects of Dexamethasone on Postoperative Glycemic Control in Patients After Primary Total Joint Arthroplasty: A Randomized Double-Blind Controlled Trial.

BACKGROUND: In patients undergoing total joint arthroplasty (TJA), the use of dexamethasone (DEX) may cause perioperative blood glucose (BG) disorders, leading to complications even in patients who do not have diabetes. We aimed to evaluate the effects of different DEX doses on perioperative BG levels. METHODS: A total of 135 patients who do not have diabetes were randomized into three groups: preoperative intravenous injection of normal saline (Group A, the placebo group), preoperative intravenous injection of 10 mg DEX (Group B), and preoperative intravenous injection of 20 mg DEX (Group C). Postoperative fasting blood glucose (FBG) levels were designated as the primary outcome, while postoperative postprandial blood glucose (PBG) levels were assigned as the secondary outcome. The incidence of complications was recorded. We also investigated the risk factors for FBG ≥ 140 mg/dl and PBG ≥ 180 mg/dl. RESULTS: The FBG levels were higher in Groups B and C than in Group A on postoperative days (POD) 0 and 1. The PBG levels were lower for Groups A and B compared to Group C on POD 1. No differences in FBG or PBG were detected beyond POD 1. Elevated preoperative glycosylated hemoglobin A1c (HbA1c) levels increased the risk of FBG ≥ 140 mg/dl and PBG ≥ 180 mg/dl, respectively. However, preoperative intravenous injection of DEX was not associated with FBG ≥ 140 mg/dl or PBG ≥ 180 mg/dl. No differences were found in postoperative complications among the three groups. CONCLUSION: The preoperative intravenous administration of 10 or 20 mg DEX in patients who do not have diabetes showed transient effects on postoperative BG after TJA. The preoperative HbA1c level threshold (regardless of the administration or dosage of DEX) that increased the risk for the occurrence of FBG ≥ 140 mg/dl and PBG ≥ 180 mg/dl was 5.75% and 5.85%, respectively.

Mated-Atom Nanozymes with Efficient Assisted NAD+ Replenishment for Skin Regeneration.

Excessive accumulation of reduced nicotinamide adenine dinucleotide (NADH) within biological organisms is closely associated with many diseases. It remains a challenge to efficiently convert superfluous and detrimental NADH to NAD+. NADH oxidase (NOX) is a crucial oxidoreductase that catalyzes the oxidation of NADH to NAD+. Herein, M1M2 (Mi=V/Mn/Fe/Co/Cu/Mo/Rh/Ru/Pd, i = 1 or 2) mated-atom nanozymes (MANs) are designed by mimicking natural enzymes with polymetallic active centers. Excitingly, RhCo MAN possesses excellent and sustainable NOX-like activity, with Km-NADH (16.11 µM) being lower than that of NOX-mimics reported so far. Thus, RhCo MAN can significantly promote the regeneration of NAD+ and regulate macrophage polarization toward the M2 phenotype through down-regulation of TLR4 expression, which may help to recover skin regeneration. However, RhRu MAN with peroxidase-like activity and RhMn MAN with superoxide dismutase-like activity exhibit little modulating effects on eczema. This work provides a new strategy to inhibit skin inflammation and promote skin regeneration.

Melatonin pretreatment improves endometrial regenerative cell-mediated therapeutic effects in experimental colitis.

BACKGROUND: Endometrial regenerative cells (ERCs) have been proven to be an effective strategy for attenuating experimental colitis, but the complex in vivo microenvironment such as oxidative stress may largely limit and weaken ERC efficacy. Melatonin (MT) works as an anti-oxidative agent in a variety of preclinical diseases, and has been identified to promote mesenchymal stem cell-mediated therapeutic effects in different diseases. However, the ability of MT to enhance ERC-mediated effects in colitis is currently poorly understood. METHODS: Menstrual blood was collected from healthy female volunteers to obtain ERCs and identified. In vitro, H2O2-induced oxidative stress was introduced to test if MT could prevent ERCs from damage through detection of intracellular reactive oxidative species (ROS) and apoptosis assay. In vivo, dextran sodium sulfate (DSS)-induced acute colitis was treated by ERCs and MT-primed ERCs, therapeutic effects were assayed by the disease activity index (DAI), histological features, and macrophage and CD4+ T cell in the spleen and colon, and cytokine profiles in the sera and colon were also measured. RESULTS: In vitro, ERCs that underwent MT-precondition were found to possess more anti-oxidative potency in comparison to naïve ERCs, which were characterized by decreased apoptosis rate and intracellular ROS under H2O2 stimulation. In vivo, MT pretreatment can significantly enhance the therapeutic effects of ERCs in the attenuation of experimental colitis, including decreased DAI index and damage score. In addition, MT pretreatment was found to promote ERC-mediated inhibition of Th1, Th17, and M1 macrophage and pro-inflammatory cytokines, increase of Treg, and immunomodulation of cytokines in the spleen and colon. CONCLUSIONS: MT pretreatment facilitates the promotion of cell viability under oxidative stress in vitro, while also enhancing ERC-mediated therapeutic effects in experimental colitis.

Protein disulfide isomerase cleaves allosteric disulfides in histidine-rich glycoprotein to regulate thrombosis.

The essence of difference between hemostasis and thrombosis is that the clotting reaction is a highly fine-tuned process. Vascular protein disulfide isomerase (PDI) represents a critical mechanism regulating the functions of hemostatic proteins. Herein we show that histidine-rich glycoprotein (HRG) is a substrate of PDI. Reduction of HRG by PDI enhances the procoagulant and anticoagulant activities of HRG by neutralization of endothelial heparan sulfate (HS) and inhibition of factor XII (FXIIa) activity, respectively. Murine HRG deficiency (Hrg-/-) leads to delayed onset but enhanced formation of thrombus compared to WT. However, in the combined FXII deficiency (F12-/-) and HRG deficiency (by siRNA or Hrg-/-), there is further thrombosis reduction compared to F12-/- alone, confirming HRG's procoagulant activity independent of FXIIa. Mutation of target disulfides of PDI leads to a gain-of-function mutant of HRG that promotes its activities during coagulation. Thus, PDI-HRG pathway fine-tunes thrombosis by promoting its rapid initiation via neutralization of HS and preventing excessive propagation via inhibition of FXIIa.

Metabolic and Bioprocess Engineering of Clostridium tyrobutyricum for Butyl Butyrate Production on Xylose and Shrimp Shell Waste.

Microbial conversion of agri-food waste to valuable compounds offers a sustainable route to develop the bioeconomy and contribute to sustainable biorefinery. Clostridium tyrobutyricum displays a series of native traits suitable for high productivity conversion of agri-food waste, which make it a promising host for the production of various compounds, such as the short-chain fatty acids and their derivative esters products. In this study, a butanol synthetic pathway was constructed in C. tyrobutyricum, and then efficient butyl butyrate production through in situ esterification was achieved by the supplementation of lipase into the fermentation. The butyryl-CoA/acyl-CoA transferase (cat1) was overexpressed to balance the ratio between precursors butyrate and butanol. Then, a suitable fermentation medium for butyl butyrate production was obtained with xylose as the sole carbon source and shrimp shell waste as the sole nitrogen source. Ultimately, 5.9 g/L of butyl butyrate with a selectivity of 100%, and a productivity of 0.03 g/L·h was achieved under xylose and shrimp shell waste with batch fermentation in a 5 L bioreactor. Transcriptome analyses exhibited an increase in the expression of genes related to the xylose metabolism, nitrogen metabolism, and amino acid metabolism and transport, which reveal the mechanism for the synergistic utilization of xylose and shrimp shell waste. This study presents a novel approach for utilizing xylose and shrimp shell waste to produce butyl butyrate by using an anaerobic fermentative platform based on C. tyrobutyricum. This innovative fermentation medium could save the cost of nitrogen sources (~97%) and open up possibilities for converting agri-food waste into other high-value products.

Structural, Thermal, Pasting and Digestion Properties of Starches from Developing Root Tubers of Sweet Potato.

Three sweet potato varieties with white-, yellow- and purple-fleshed root tubers were harvested at 100, 120, 140 and 160 days after planting (DAP). Their starch structural, thermal, pasting and digestion properties were measured to reveal the influences of harvesting dates on the physicochemical properties of sweet potato root tuber starch. Though starches from different varieties displayed some differences in physicochemical properties due to their different genetic backgrounds, they were influenced by harvesting date in similar ways. Starches isolated from root tubers at 100 and 160 DAP exhibited lower granule sizes than those at 120 and 140 DAP. The amylose content was higher in root tubers at 100 and 120 DAP than at 140 and 160 DAP. Starches from root tubers at 100 DAP exhibited CA-type X-ray diffraction patterns, and then the B-type crystallinity gradually increased at later harvesting dates. The different harvesting dates had no significant effects on the short-ranged ordered structure and lamellar thickness of starch, but the lamellar peak intensity decreased significantly at later harvesting dates. Starch had a lower gelatinization temperature and a wider gelatinization temperature range in root tubers at 140 and 160 DAP than at 100 and 120 DAP. The higher peak viscosity and lower pasting temperature were associated with the late harvesting date. The digestion of starch had slight differences among root tubers at different harvesting dates. The harvesting dates of root tubers played more important roles in starch properties than the variety. This study would be helpful for breeders, farmers and sweet potato starch users.

Superconductivity in Ca-intercalated bilayer graphene: C2CaC2.

The deposition and intercalation of metal atoms can induce superconductivity in monolayer and bilayer graphenes. For example, it has been experimentally proved that Li-deposited graphene is a superconductor with critical temperature Tc of 5.9 K, Ca-intercalated bilayer graphene C6CaC6 and K-intercalated epitaxial bilayer graphene C8KC8 are superconductors with Tc of 2-4 K and 3.6 K, respectively. However, the Tc of them are relatively low. To obtain higher Tc in graphene-based superconductors, here we predict a new Ca-intercalated bilayer graphene C2CaC2, which shows higher Ca concentration than the C6CaC6. It is proved to be thermodynamically and dynamically stable. The electronic structure, electron-phonon coupling (EPC) and superconductivity of C2CaC2 are investigated based on first-principles calculations. The EPC of C2CaC2 mainly comes from the coupling between the electrons of C-pz orbital and the high- and low-frequency vibration modes of C atoms. The calculated EPC constant λ of C2CaC2 is 0.75, and the superconducting Tc is 18.9 K, which is much higher than other metal-intercalated bilayer graphenes. By further applying -4% biaxial compressive strain to C2CaC2, the Tc can be boosted to 26.6 K. Thus, the predicted C2CaC2 provides a new platform for realizing superconductivity with the highest Tc in bilayer graphenes.

Achromobacter seleniivolatilans sp. nov. and Buttiauxella selenatireducens sp. nov., isolated from the rhizosphere of selenium hyperaccumulator Cardamine hupingshanesis.

Two Gram-stain-negative bacterial strains, R39T and R73T, were isolated from the rhizosphere soil of the selenium hyperaccumulator Cardamine hupingshanesis in China. Strain R39T transformed selenite into elemental and volatile selenium, whereas strain R73T transformed both selenate and selenite into elemental selenium. Phylogenetic and phylogenomic analyses indicated that strain R39T belonged to the genus Achromobacter, while strain R73T belonged to the genus Buttiauxella. Strain R39T (genome size, 6.68 Mb; G+C content, 61.6 mol%) showed the closest relationship to Achromobacter marplatensis LMG 26219T and Achromobacter kerstersii LMG 3441T, with average nucleotide identity (ANI) values of 83.6 and 83.4 %, respectively. Strain R73T (genome size, 5.22 Mb; G+C content, 50.3 mol%) was most closely related to Buttiauxella ferragutiae ATCC 51602T with an ANI value of 86.4 %. Furthermore, strain A111 from the GenBank database was found to cluster with strain R73T within the genus Buttiauxella through phylogenomic analyses. The ANI and digital DNA-DNA hybridization values between strains R73T and A111 were 97.5 and 80.0% respectively, indicating that they belong to the same species. Phenotypic characteristics also differentiated strain R39T and strain R73T from their closely related species. Based on the polyphasic analyses, strain R39T and strain R73T represent novel species of the genera Achromobacter and Buttiauxella, respectively, for which the names Achromobacter seleniivolatilans sp. nov. (type strain R39T=GDMCC 1.3843T=JCM 36009T) and Buttiauxella selenatireducens sp. nov. (type strain R73T=GDMCC 1.3636T=JCM 35850T) are proposed.