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Ge-containing Lewis acidic zeolites are typically synthesized using a conventional hydrothermal strategy from amorphous silica sources, through a long time- and energy-consuming approach limiting their wide applications. This study reports a rapid synthesis strategy for a series of IWV aluminogermanosilicate zeolites (T-x-Al) with a wide range of Si/Ge molar ratios (5–15) by interzeolite transformation of dealuminated FAU (DA-FAU). Notably, Ge-rich IWV could be obtained with crystallization time as short as one day by the equimolecular Si/Ge ratio gel. The effect of synthetic parameters was investigated and the obtained T-x-Al samples were characterized by XRD, SEM, EDS, ICP, 29Si and 27Al MAS NMR, FTIR, and N2 physisorption analyses. Compared with a previously reported IWV germanosilicate (H-3), T-x-Al displayed a better catalytic activity in Baeyer-Villiger (BV) oxidation, attributed to the presence of the active framework Ge sites with the assistance of the extra-framework Al species. The cyclic catalysis tests revealed that the presence of framework Al species contributed to the stability of the T-x-Al. Specifically, T-x-Al, with 14-membered ring (MR) supercages, outperformed the typical 12-MR Sn-beta catalyst in the BV oxidation of large ketone-like 2-admantanone, indicating a promising potential application in the macromolecular catalytic process. [ABSTRACT FROM AUTHOR]

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Purpose: This study aimed to investigate the association between unilateral high-riding vertebral artery (HRVA) and morphological changes in the atlantoaxial joint (AAJ) and to determine whether unilateral HRVA is a risk factor for atlantoaxial osteoarthritis (AAOA). Methods: We conducted a retrospective analysis of 2496 patients admitted to our medical center between January 2020 and December 2022 who underwent CT imaging of the cervical spine. Two hundred and seventy-two patients with unilateral HRVA (HRVA group) were identified and a respective 2:1 age- and sex-matched control group without HRVA was built. Morphological parameters, including C2 lateral mass settlement (C2 LMS), C1/2 coronal inclination (C1/2 CI), lateral atlanto-dental interval (LADI), and C1/2 relative rotation angle (C1/2 RRA) were measured. The degree of AAOA was recorded. Risk factors associated with AAOA were identified using univariate and multivariable logistic regression analyses. Results: The study included 61.4% women, and the overall average age of the study population was 48.7 years. The morphological parameters (C2 LMS, C1/2 CI, and LADI) in AAJ were asymmetric between the HRVA and the non-HRVA sides in the HRVA group (p < 0.001). These differences in parameters (d-C2 LMS, d-C1/2 CI, and d-LADI) between the HRVA and the non-HRVA sides, and C1/2 RRA were significantly larger than those in the control group. Eighty-three of 816 patients (10.2%) with AAOA had larger values of d-C2 LMS, d-C1/2 CI, d-LADI, and C1/2 RRA compared with the patients without AAOA (p < 0.05). The multivariable logistic regression analysis indicated that unilateral HRVA [adjusted odds ratio (OR) = 2.6, 95% CI: 1.1–6.3, p = 0.029], age in the sixth decade or older (adjusted OR = 30.2, 95% CI: 16.1–56.9, p < 0.001), women (adjusted OR = 2.1, 95% CI: 1.0–5.6, P = 0.034) were independent risk factors for AAOA. Conclusion: Unilateral HRVA was associated with asymmetric morphological changes of nonuniform settlement of C2 lateral mass, lateral slip of atlas, and atlantoaxial rotation displacement. Besides age ≥ 60 years and females, unilateral HRVA is an independent risk factor for AAOA. [ABSTRACT FROM AUTHOR]

This paper is concerned with event-triggered H∞ control of sampled-data systems. Its novelties lie in three aspects: (i) A novel accumulated-state-error-based event-triggered scheme is introduced by comparing the integral of the state error from tk to t with the system state sampled at tk. This condition works well due to the fact that the so-called Zeno behaviour does not occur. (ii) A novel Lyapunov functional is constructed to establish a criterion to ensure some certain H∞ performance of the closed-loop system. This Lyapunov functional is dependent on the integral of the state error involved in the event-triggered scheme. (iii) Under the event-triggered sampling scheme, suitable state-feedback controllers can be designed rather than be given a priori. Moreover, a self-triggered implementation of the proposed event-triggered sampling scheme is presented as well. Finally, a batch reactor model and an inverted pendulum system are given to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Elemental Te is important for semiconductor applications including thermoelectric energy conversion. Introducing dopants such as As, Sb, and Bi has been proven critical for improving its thermoelectric performance. However, the remarkably low solubility of these elements in Te raises questions about the mechanism with which these dopants can improve the thermoelectric properties. Indeed, these dopants overwhelmingly form precipitates rather than dissolve in the Te lattice. To distinguish the role of doping and precipitation on the properties, we have developed a correlative method to locally determine the structure-property relationship for an individual matrix or precipitate. We reveal that the conspicuous enhancement of electrical conductivity and power factor of bulk Te stems from the dopant-induced metavalently bonded telluride precipitates. These precipitates form electrically beneficial interfaces with the Te matrix. A quantum-mechanical-derived map uncovers more candidates for advancing Te thermoelectrics. This unconventional doping scenario adds another recipe to the design options for thermoelectrics and opens interesting pathways for microstructure design. Doping is a common strategy to improve thermoelectric performance yet limited to the solid solubility of dopants. Here, the authors find that forming metavalently bonded precipitates is key to property enhancement in Te rather than modifying the matrix lattice. [ABSTRACT FROM AUTHOR]

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Reactive sulfane sulfur species such as persulfides (RSSH) and H2S2 are important redox regulators and closely linked to H2S signaling. However, the study of these species is still challenging due to their instability, high reactivity, and the lack of suitable donors to produce them. Herein we report a unique compound, 2H-thiopyran-2-thione sulfine (TTS), which can specifically convert H2S to HSOH, and then to H2S2 in the presence of excess H2S. Meanwhile, the reaction product 2H-thiopyran-2-thione (TT) can be oxidized to reform TTS by biological oxidants. The reaction mechanism of TTS is studied experimentally and computationally. TTS can be conjugated to proteins to achieve specific delivery, and the combination of TTS and H2S leads to highly efficient protein persulfidation. When TTS is applied in conjunction with established H2S donors, the corresponding donors of H2S2 (or its equivalents) are obtained. Cell-based studies reveal that TTS can effectively increase intracellular sulfane sulfur levels and compensate for certain aspects of sulfide:quinone oxidoreductase (SQR) deficiency. These properties make TTS a conceptually new strategy for the design of donors of reactive sulfane sulfur species. Reactive sulfane sulfur species such as persulfides and H2S2 are important redox regulators and linked to H2S signaling, but their study is hindered by a lack of suitable donors to produce them. Here, the authors report 2H-thiopyran-2-thione sulfine (TTS), a compound which can specifically convert H2S to HSOH, and then to H2S2 in the presence of excess H2S. [ABSTRACT FROM AUTHOR]

Background: Hepatic pedicle clamping (HPC) is frequently utilized during hepatectomy to reduce intraoperative bleeding and diminish the need for intraoperative blood transfusion (IBT). The long-term prognostic implications of HPC following hepatectomy for hepatocellular carcinoma (HCC) remain under debate. This study aims to elucidate the association between HPC and oncologic outcomes after HCC resection, stratified by whether IBT was administered. Patients and Methods: Prospectively collected data on patients with HCC who underwent curative resection from a multicenter database was studied. Patients were stratified into two cohorts on the basis of whether IBT was administered. The impact of HPC on long-term overall survival (OS) and recurrence-free survival (RFS) between the two cohorts was assessed by univariable and multivariable Cox regression analyses. Results: Of 3362 patients, 535 received IBT. In the IBT cohort, using or not using HPC showed no significant difference in OS and RFS outcomes (5-year OS and RFS rates 27.9% vs. 24.6% and 13.8% vs. 12.0%, P = 0.810 and 0.530). However, in the non-IBT cohort of 2827 patients, the HPC subgroup demonstrated significantly decreased OS (5-year 45.9% vs. 56.5%, P < 0.001) and RFS (5-year 24.7% vs. 33.3%, P < 0.001) when compared with the subgroup without HPC. Multivariable Cox regression analysis identified HPC as an independent risk factor of OS and RFS [hazard ratios (HR) 1.16 and 1.12, P = 0.024 and 0.044, respectively] among patients who did not receive IBT. Conclusions: The impact of HPC on the oncological outcomes following hepatectomy for patients with HCC differed significantly whether IBT was administered, and HPC adversely impacted on long-term survival for patients without receiving IBT during hepatectomy. [ABSTRACT FROM AUTHOR]

Background and Objective: According to the Barcelona Clinic Liver Cancer (BCLC) algorithm, tumor burden and liver function, but not tumor biology, are the key factors in determining tumor staging and treatment modality, and evaluating treatment prognosis. The serum α‐fetoprotein (AFP) level is an important characteristic of hepatocellular carcinoma (HCC) biology, and we aimed to evaluate its prognostic value for patients undergoing liver resection of early-stage HCC. Methods: Patients who underwent curative liver resection for early-stage HCC were identified from a multi‐institutional database. Patients were divided into three groups according to preoperative AFP levels: low (< 400 ng/mL), high (400–999 ng/mL), and extremely-high (≥ 1000 ng/mL) AFP groups. Overall survival (OS) and recurrence rates were compared among these three groups. Results: Among 1284 patients, 720 (56.1%), 262 (20.4%), and 302 (23.5%) patients had preoperative low, high, and extremely-high AFP levels, respectively. The cumulative 5-year OS and recurrence rates were 71.3 and 38.9% among patients in the low AFP group, 66.3 and 48.5% in the high AFP group, and 45.7 and 67.2% in the extremely-high AFP group, respectively (both p < 0.001). Multivariate Cox regression analysis identified both high and extremely-high AFP levels to be independent risk factors of OS (hazard ratio [HR] 1.275 and 1.978, 95% confidence interval [CI] 1.004–1.620 and 1.588–2.464, respectively; p = 0.047 and p < 0.001, respectively) and recurrence (HR 1.290 and 2.050, 95% CI 1.047–1.588 and 1.692–2.484, respectively; p = 0.017 and p < 0.001, respectively). Conclusions: This study demonstrated the important prognostic value of preoperative AFP levels among patients undergoing resection for early-stage HCC. Incorporating AFP to prognostic estimation of the BCLC algorithm can help guide individualized risk stratification and identify neoadjuvant/adjuvant treatment necessity. [ABSTRACT FROM AUTHOR]

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

Because of the limited effectiveness of prevailing phylogenetic methods when applied to highly divergent protein sequences, the phylogenetic analysis problem remains challenging. Here, we propose a sequence-based evolutionary distance algorithm termed sequence distance (SD), which innovatively incorporates site-to-site correlation within protein sequences into the distance estimation. In protein superfamilies, SD can effectively distinguish evolutionary relationships both within and between protein families, producing phylogenetic trees that closely align with those based on structural information, even with sequence identity less than 20%. SD is highly correlated with the similarity of the protein structure, and can calculate evolutionary distances for thousands of protein pairs within seconds using a single CPU, which is significantly faster than most protein structure prediction methods that demand high computational resources and long run times. The development of SD will significantly advance phylogenetics, providing researchers with a more accurate and reliable tool for exploring evolutionary relationships. [ABSTRACT FROM AUTHOR]

Purpose: Culture-negative urine specimens can be rapidly screened by urine flow cytometry (UFC), while low positive predictive value (PPV) limits the clinical application. We explored the factors associated with a low PPV. Methods: A total of 5095 urine specimens were analyzed with UFC and culture. Diagnostic performance of leukocytes, bacteria, and BACT-info flags was evaluated by sensitivity, specificity, PPV, and negative predictive value (NPV). The association of contaminated culture and squamous epithelial cell count and BACT-info flag was performed by logistic regression analysis. Results: The NPVs of parallel combination of bacteria and leucocytes were 98.9% in males and 97.9% in females, and PPVs of serial combination were 86.6% and 77.8% in men and women, respectively. The PPV of Gram-negative flag was higher than that of Gram-positive flag. The proportions of contamination in the urine culture results of false positive specimens were 86.9% in males and 98.5% in females at the cutoff points of the serial combination, and these parameters were 53.2% in males and 85.6% in females for the Gram-positive flag. There was a statistically significant association between contaminated cultures and squamous epithelial cells count in females, but not in males. Associations between contaminated cultures and Gram-positive flags or Gram-pos/-neg flags were statistically significant, but there was no association between contaminated cultures and Gram-negative flags. Conclusions: A serial combination of leukocytes and bacteria may maximize PPV in the diagnosis of bacterial urinary tract infection by urine flow cytometry, and contamination is the main reason for a low PPV. [ABSTRACT FROM AUTHOR]

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

By tactically integrating two different kinds of proton donors and acceptors into one supramolecular tecton, a new crystalline hydrogen-bonded organic framework (HOF-SXU-1) has been developed. HOF-SXU-1 features a remarkable proton conductivity as high as 6.32 mS cm−1 and an extremely low activation energy of 0.16 eV at 160 °C under anhydrous N2 conditions. By contrast, under identical conditions, the organic precursors of HOF-SXU-1 only exhibit negligible proton conduction performance, demonstrating that the formation of HOF is crucial for excellent proton conduction performance. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "A sequence-based evolutionary distance method for Phylogenetic analysis of highly divergent proteins" published in Scientific Reports. The correction addresses an error in Figure 3, panel b, where the labels were not displayed correctly. The corrected version of the article is now available. The authors of the article are Wei Cao, Lu-Yun Wu, Xia-Yu Xia, Xiang Chen, Zhi-Xin Wang, and Xian-Ming Pan. [Extracted from the article]

Molecular dynamics simulations are conducted to study the self-diffusion process along a < 100 > Σ5(210) symmetric tilt grain boundary in a model equiatomic FeNiCrCoCu high-entropy alloy (HEA), for the directions both perpendicular and parallel to the tilt axis. For comparison, the grain boundary diffusion process is also quantified for each of the pure components of the HEA. Most importantly, the results are compared with the diffusion along the same grain boundary using the corresponding "average atom" potential that has similar average bulk properties but no compositional randomness as in the HEA. These comparisons show that the self-diffusion in the HEA grain boundary is slower than in the average atom material as well as the average of pure components, suggesting that a "sluggish" diffusion effect exists for this special grain boundary in the HEA. This effect is significant at low temperatures but diminishes at higher temperatures, indicating that the grain boundary sluggish diffusion is likely temperature dependent. Interestingly, the grain boundary sluggish diffusion behavior is different from the bulk diffusion that was studied previously using the same methods and interatomic potentials, in which no significant sluggish diffusion effect was observed. Our further analysis suggests that the combination of the "trapping effect" by compositional complexity in the HEA and the confined 2-D diffusion paths at this special grain boundary is responsible for the observed grain boundary sluggish diffusion. [ABSTRACT FROM AUTHOR]

NiFe composites have been regarded as promising candidates to replace commercial noble-based electrocatalysts for the oxygen evolution reaction (OER). However, their practical applications still suffer from poor conductivity, limited activity, and durability. To address these issues, herein, by utilizing three-dimensional covalent organic framework (3D-COF) with porous confined structures and abundant coordinate N sites as the precursor, the partially oxidized Ni3Fe nanoalloys wrapped by N-doped carbon (N-C) layers are constructed via simple pyrolysis and subsequent oxidization. Benefiting from the 3D curved hierarchical structure, high-conductivity of Ni3Fe and N-C layers, and well-distributed active sites, the as-synthesized O-Ni3Fe-N-C catalyst demonstrates excellent activity and durability for catalyzing OER. Experimental and theoretical analyses disclose that both high-temperature oxidization and the OER process greatly promote the formation and exposure of the Ni(Fe)OOH active species as well as lower charge transfer resistance, inducing its optimized OER activity. The robust graphitized N-C layers with superior conductivity and their couplings with oxidized Ni3Fe nanoalloys are beneficial for stabilizing catalytic centers, thereby imparting O-Ni3Fe-N-C with such outstanding stability. This work not only provides a rational guidance for enriching and stabilizing high-activity catalytic sites towards OER but also offers more insights into the structural evolution of NiFe-based OER catalysts. [ABSTRACT FROM AUTHOR]

Exosomes make a significant contribution during stem cell-based therapy due to the abundant contents. Accumulating evidence implies exosomes can act as potential biological nano agents. We herein propose hypoxic preconditioning for neural stem cells (NSCs) that could produce hypoxic exosomes for efficient treatment of ischemic stroke. Hypoxic preconditioning on NSCs significantly altered the miRNAs encapsulated in exosomes. Notably, hypoxic exosomes could target the injured brain to regulate the microenvironment to inhibit neuroinflammation and promote blood-brain barrier permeability recovery. Additionally, the autologous NSCs in Nestin-CreER mice could be activated by hypoxic exosomes to facilitate nerve regeneration. After hypoxic preconditioning, exosomes further exerted therapeutic effects on both survival (25%) and behavioral outcomes in ischemic stroke mice. Overall, hypoxic preconditioning NSCs can produce effective nano agent and may represent a promising strategy for clinical neurorestorative therapy. [ABSTRACT FROM AUTHOR]

A partial ligand exchange strategy for fabricating catalytically active single palladium site immobilized on zeolitic imidazolate framework-8 (ZIF-8, Pd1/ZIF-8) is proposed in this work. The one-step synthesis simply involves reacting Na2PdCl4 with ZIF-8 in solvent. The Cl ligands of Na2PdCl4 exchanged with 2-methylimidazole (2-MeIm) of the framework, resulting in the anchoring Pd on the framework and dissociation of Zn into the solution. The whole synthesis is performed at ambient conditions and the crystalline integrity of ZIF-8 is well retained. The resulting Pd1/ZIF-8 is extensively characterized by different techniques which confirm the proposed mechanism. Pd1/ZIF-8 is also successfully applied in the size-selective semi-hydrogenation of alkynes. [ABSTRACT FROM AUTHOR]

Cryptosporidium infects gastrointestinal epithelium and is a leading cause of infectious diarrhea and diarrheal-related death in children worldwide. There are no vaccines and no fully effective therapy available for the infection. Type II and III interferon (IFN) responses are important determinants of susceptibility to infection but the role for type I IFN response remains obscure. Cryptosporidium parvum virus 1 (CSpV1) is a double-stranded RNA (dsRNA) virus harbored by Cryptosporidium spp. Here we show that intestinal epithelial conditional Ifnar1−/− mice (deficient in type I IFN receptor) are resistant to C. parvum infection. CSpV1-dsRNAs are delivered into host cells and trigger type I IFN response in infected cells. Whereas C. parvum infection attenuates epithelial response to IFN-γ, loss of type I IFN signaling or inhibition of CSpV1-dsRNA delivery can restore IFN-γ-mediated protective response. Our findings demonstrate that type I IFN signaling in intestinal epithelial cells is detrimental to intestinal anti-C. parvum defense and Cryptosporidium uses CSpV1 to activate type I IFN signaling to evade epithelial antiparasitic response. Cryptosporidium parvum virus 1 is a virus harbored by the pathogenic protozoan Cryptosporidium parvum, and whose role in parasite biology and host interactions remains unclear. Here, Deng et al. demonstrate the impact this virus has on host response and infection outcome. [ABSTRACT FROM AUTHOR]

Atherosclerosis is the main pathological basis of cardiovascular disease and involves damage to vascular endothelial cells (ECs) that results in endothelial dysfunction (ED). The vascular endothelium is the key to maintaining blood vessel health and homeostasis. ED is a complex pathological process involving inflammation, shear stress, vascular tone, adhesion of leukocytes to ECs, and platelet aggregation. The activation of P2X4, P2X7, and P2Y2 receptors regulates vascular tone in response to shear stress, while activation of the A2A, P2X4, P2X7, P2Y1, P2Y2, P2Y6, and P2Y12 receptors promotes the secretion of inflammatory cytokines. Finally, P2X1, P2Y1, and P2Y12 receptor activation regulates platelet activity. These purinergic receptors mediate ED and participate in atherosclerosis. In short, P2X4, P2X7, P2Y1, and P2Y12 receptors are potential therapeutic targets for atherosclerosis. [ABSTRACT FROM AUTHOR]

The dynamic mechanical properties and the damage prediction are critical for 3003 aluminum alloy during its safety application on lightweight automobile. Dynamic tensile properties at strain rate from 1 to 500 s−1 were analyzed, and the damage behavior was simulated by using the GISSMO model based on original and modified Johnson–Cook (JC) constitutive equation. The experimental results demonstrated that 3003 alloy exhibited significant strain rate sensitivity in the yield strength and fracture prolongation. JC model was modified based on the GISSMO damage parameter. A damage behavior of 3003 aluminum alloy was predicted accurately by using the modified JC equation. The reliability of the modified JC model was verified by using the cupping experiment and the simulation. [ABSTRACT FROM AUTHOR]

Background: Although hepatitis B virus (HBV) infection remains the main cause of hepatocellular carcinoma (HCC) worldwide, metabolic syndrome, with its increase in prevalence, has become an important and significant risk factor for HCC. This study was designed to investigate the association of concurrent metabolic syndrome with long-term prognosis following liver resection for patients with HBV-related HCC. Methods: From a Chinese, multicenter database, HBV-infected patients who underwent curative resection for HCC between 2010 and 2020 were identified. Long-term oncological prognosis, including overall survival (OS), recurrence-free survival (RFS), and early (≤2 years of surgery) and late (>2 years) recurrences were compared between patients with versus those without concurrent metabolic syndrome. Results: Of 1753 patients, 163 (9.3%) patients had concurrent metabolic syndrome. Compared with patients without metabolic syndrome, patients with metabolic syndrome had poorer 5-year OS (47.5% vs. 61.0%; P = 0.010) and RFS (28.3% vs. 44.2%; P = 0.003) rates and a higher 5-year overall recurrence rate (67.3% vs. 53.3%; P = 0.024). Multivariate analysis revealed that concurrent metabolic syndrome was independently associated with poorer OS (hazard ratio: 1.300; 95% confidence interval: 1.018–1.660; P = 0.036) and RFS (1.314; 1.062–1.627; P = 0.012) rates, and increased rates of late recurrence (hazard ratio: 1.470; 95% confidence interval: 1.004–2.151; P = 0.047). Conclusions: In HBV-infected patients with HCC, concurrent metabolic syndrome was associated with poorer postoperative long-term oncologic survival outcomes. These results suggested that patients with metabolic syndrome should undergo enhanced surveillance for tumor recurrence even after 2 years of surgery to early detect late HCC recurrence. Whether improving metabolic syndrome can reduce postoperative recurrence of HCC deserves further exploration. [ABSTRACT FROM AUTHOR]

The invertibility of a Toeplitz matrix can be assessed based on the solvability of two standard equations. The inverse of the nonsingular Toeplitz matrix can then be represented as the sum of products of circulant and skew-circulant (CS) matrices. In this note, we provide a new structured perturbation analysis for the CS representation of Toeplitz inversion and the new upper bound is just half as large as the existing upper bound proposed by Wu et al. (Numer Linear Algebra Appl 22(4):777–792, 2015) and Feng et al. (East Asian J Appl Math 5(2):160–175, 2015). Meanwhile, some practical issues and numerical experiments involving the numerical solutions of fractional partial differential equations are reported to support our theoretical findings. [ABSTRACT FROM AUTHOR]

In this paper, we present a new block preconditioner for solving the saddle point linear systems. The proposed method is developed from an augmented reformulation of the saddle point problem into a new linear system with an almost block triangular coefficient matrix. Theoretical results are derived on the eigenvalue distribution of the preconditioned matrix, and an efficient algorithmic implementation is developed and presented. Several numerical examples are reported to support the theoretical findings and to illustrate the favourable convergence properties of the proposed preconditioner, also compared to other popular solvers for saddle point problems. [ABSTRACT FROM AUTHOR]

The study objective was to observe the treatment effect of the farnesoid X receptor (FXR) agonist GW4064 in a rat model of hilar cholangiocarcinoma to explore a new therapeutic target for gene therapy for hilar cholangiocarcinoma. Eighty male Wistar rats were randomly divided into four groups (treatment group, model group, control group and sham operation group, 20 rats in each group). The four groups were fed a standard diet. The treatment group and the model group were injected with a suspension of cholangiocarcinoma QBC939 cells into the hilar bile duct with a microsyringe, the control group was injected with normal saline, and the sham operation group was not injected with anything. A modified tail suspension test (TST) was used to evaluate the vitality of the rats. At 4 weeks, one rat in the treatment group and model group was euthanized, and the changes in the hilar bile duct were recorded. The procedure was repeated at 6 weeks. After 6 weeks, hilar cholangiocarcinoma occurred in the treatment group and model group. Then, the treatment group was injected with GW4064 intraperitoneally at a dose of 50 mg/kg/day. One week after injection, the rats in the four groups were euthanized. Pathological examination confirmed that tumours had formed, and hilar bile duct tissues were taken from the four groups. FXR, Bsep, Ntcp and NF-κB expression in the hilar bile duct was detected by real-time polymerase chain reaction (RT–PCR) and immunohistochemistry. After three weeks, the rats in the treatment group and model group ate less, and their weight was significantly reduced. Six weeks later, hilar cholangiocarcinoma was detected in the treatment group and model group. After treatment with GW4064, the ratios of FXR/GAPDH mRNA, Bsep/GAPDH mRNA, Ntcp/GAPDH mRNA and NF-κBp65/GAPDH mRNA were significantly different among the four groups. Under a light microscope, FXR protein reacted with anti-FXR antibody, Bsep protein reacted with anti-Bsep antibody, Ntcp protein reacted with anti-Ntcp antibody and NF-κBp65 protein reacted with anti-NF-κBp65 antibody, and they showed granular expression. Every pathological section included 4,800 cells, and there were different numbers of positive cells in each group. FXR expression in the hilar cholangiocarcinoma of rats was significantly lower than that in normal hilar bile duct tissues. GW4064 increased the expression of FXR in tumour tissues. These findings suggest that FXR may be a new therapeutic target and that GW4064 may be helpful in the treatment of hilar cholangiocarcinoma. [ABSTRACT FROM AUTHOR]

To evaluate the effect of SGLT2 inhibitor (SGLT2i) on albuminuria, nephrin (NPH) and transforming-growth-factor-beta1 (TGF-β1) levels in urine and low-grade inflammation in type 2 diabetes (T2D) patients. A randomized, blank-controlled clinical trial included 68 T2D patients and 10 controls. Based on the urinary albumin-to-creatinine ratio (UACR), 68 diabetic patients were stratified into three levels, UACR < 30 mg/g, UACR ≧ 30 mg/g to ≦ 300 mg/g and UACR ˃ 300 mg/g, who were randomized (1:1:1) to receive SGLT2i treatment for 12 weeks. The concentrations of NPH and TGF-β1 in urine were measured as indications of podocyte injury and renal fibrosis. Low-grade inflammation was assessed by the levels of IL-6, TNFα and hsCRP. After 12 weeks of SGLT2i treatment, the levels of UACR and NPH decreased, UTGF-β1 increased in the T2D with microalbuminuria and macroalbuminuria groups, NPH (1.12 [0.59, 1.29] vs. 0.71 [0.41, 1.07] µg/ml, P = 0.022) and (1.29 [0.99, 1.96] vs. 0.93 [0.57, 1.31] µg/ml, P = 0.002), UTGF-β1 (4.88 ± 1.31 vs. 7.27 ± 1.21 pg/ml, P < 0.001) and (4.30 ± 1.34 vs. 6.78 ± 2.59 pg/ml, P < 0.001), respectively. The changes in NPH were positively correlated with the UACR and negatively correlated with UTGF-β1 in T2D with albuminuria. SGLT2i alleviate nephrin loss and enhance TGF-β1 excretion in urine in T2DM with albuminuria. The anti-albuminuric effect of SGLT2i could be attributed to mitigating podocyte apoptosis and attenuating renal fibrosis. Trial registration This clinical trial was registered on 15/10/2019, in ClinicalTrials.gov, and the registry number is NCT04127084. [ABSTRACT FROM AUTHOR]

Polymerizing the narrow bandgap small-molecule architecture with a conjugated linking unit (or called the polymerized small molecule acceptors (PSMAs)) is a promising strategy to design polymer acceptors for efficient all polymer solar cells (all-PSCs). Currently, the fused-ring-based small molecule acceptors (SMAs) are preferred monomers to design efficient PSMAs, leaving the challenge of reducing the materials cost. In this work, we firstly employ nonfused-core SMA with simple synthetic procedures to design PSMAs (namely PBTI-H, PBTI-F and PBTI-Cl) to address this issue. Relative to the fused-ring based counterparts, these three PSMAs exhibit much higher figure-of-merit value. Additionally, a power-conversion efficiency of 8.80% is achieved in the PBTI-Cl-based all-PSC. The results offer an attractive approach to design low-cost PSMAs for efficient all-PSCs. [ABSTRACT FROM AUTHOR]

PageRank can be viewed as a hyperlink-based method for estimating the importance of nodes in a network, and has attracted a lot of attention from researchers. In this paper, we first propose an extrapolation procedure for PageRank vector estimation based on the linear combination of the Ritz values computed from the Hessenberg process and eigenvectors from the classical power method. In order to improve the convergence rate of the PageRank computations, the extrapolation procedure is introduced into the Hessenberg-type algorithm by Gu et al. (Numer. Algorithms, 89(4): 1845–1863, 2022), then a new algorithm is derived and named Hessenberg-extrapolation algorithm whose convergence and construction are investigated in detail. In addition, we further analyze the convergence of the Hessenberg-type algorithm and discuss the relationship between the approximate vectors of the Hessenberg-type algorithm and the Arnoldi-type algorithm. Numerical experiments on several examples demonstrate that our presented algorithm has great potential in PageRank approximation. [ABSTRACT FROM AUTHOR]

Porous silicon/carbon (Si/C) anode materials for Lithium-ion batteries was synthesized successfully by hydrochloric acid etching and calcination method using micron Si-Al alloy as silicon source and phenolic resin as carbon source. The microstructure and morphology were characterized by XRD, SEM, TEM, XPS and BET. The electrochemical performance were measured by constant current charge-discharge test and EIS. The results show that Si/C is porous structure and its pores are distributed between 1 and 6 nm. The specific discharge specific capacity of Si/C is 1287.0 mAh/g at a current density of 100 mA/g after 50 cycles, corresponding to the capacity retention of 91.0 % (for the second cycle). Si/C delivers a high specific discharge capacity of 605.9 and 359.0 mAh/g at 1 A/g and 2 A/g, respectively. The lithium ion diffusion coefficient of Si/C is 5.98 × 10− 11 cm2 s− 1, which is higher than that of 7.57 × 10− 12 cm2 s− 1 for porous Si. [ABSTRACT FROM AUTHOR]

Background: Metabolic reprogramming has emerged as a core hallmark of cancer, and cancer metabolism has long been equated with aerobic glycolysis. Moreover, hypoxia and the hypovascular tumor microenvironment (TME) are major hallmarks of pancreatic ductal adenocarcinoma (PDAC), in which glycolysis is imperative for tumor cell survival and proliferation. Here, we explored the impact of interleukin 1 receptor-associated kinase 2 (IRAK2) on the biological behavior of PDAC and investigated the underlying mechanism. Methods: The expression pattern and clinical relevance of IRAK2 was determined in GEO, TCGA and Ren Ji datasets. Loss-of-function and gain-of-function studies were employed to investigate the cellular functions of IRAK2 in vitro and in vivo. Gene set enrichment analysis, Seahorse metabolic analysis, immunohistochemistry and Western blot were applied to reveal the underlying molecular mechanisms. Results: We found that IRAK2 is highly expressed in PDAC patient samples and is related to a poor prognosis. IRAK2 knockdown led to a significant impairment of PDAC cell proliferation via an aberrant Warburg effect. Opposite results were obtained after exogenous IRAK2 overexpression. Mechanistically, we found that IRAK2 is critical for sustaining the activation of transcription factors such as those of the nuclear factor-κB (NF-κB) family, which have increasingly been recognized as crucial players in many steps of cancer initiation and progression. Treatment with maslinic acid (MA), a NF-κB inhibitor, markedly attenuated the aberrant oncological behavior of PDAC cells caused by IRAK2 overexpression. Conclusions: Our data reveal a role of IRAK2 in PDAC metabolic reprogramming. In addition, we obtained novel insights into how immune-related pathways affect PDAC progression and suggest that targeting IRAK2 may serve as a novel therapeutic approach for PDAC. [ABSTRACT FROM AUTHOR]

The variation of the morphology and distribution of cementite particles in different prior structures with spheroidizing annealing process has been proceeded in this paper. It is found that the dissolution and coarsening progresses of various initial structures in spheroidizing annealing process are quite asynchronous due to the different interlamellar spacing. The dissolution rate of degenerated pearlite (D-P) with finer interlamellar spacing is faster. The granular cementite in the spheroidized microstructure is fine, uniform and dense. The mean diameter of spherical cementite is refined to 233 nm. However, the initial structure of degenerated pearlite (D-P) is highly sensitive to the austenitization temperature. The cementite is easy to be coarsened under high austenitizing temperature. The coarsening is accompanied by the gradual increase of the Cr content in the cementite, which increases the stability of the cementite. Therefore, the optimal austenitizing temperature for degenerated pearlite (D-P) is suggested to be 770 °C. The dissolution rates of cementite in spheroidized structures are related to the initial pearlite interlamellar spacing and the austenitizing temperature. A detailed experimental research and analysis are needed on the evolution of different initial structures during spheroidizing annealing treatment. [ABSTRACT FROM AUTHOR]

We consider the holographic QCD model with a planar horizon in the D dimensions with different consistent metric solutions. We investigate the black hole thermodynamics, phase diagram and equations of state (EoS) in different dimensions. The temperature and chemical potential dependence of the drag force and diffusion coefficient also have been studied. From the results, the energy loss of heavy quark shows an enhancement near the phase transition temperature in D dimensions. This finding illustrates that the energy loss of heavy quark has a nontrivial and non-monotonic dependence on temperature. Furthermore, we find the heavy quark may lose less energy in higher dimension. The diffusion coefficient is larger in higher dimension. [ABSTRACT FROM AUTHOR]

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Drung cattle (Bos frontalis) have 58 chromosomes, differing from the Bos taurus 2n = 60 karyotype. To date, its origin and evolution history have not been proven conclusively, and the mechanisms of chromosome fusion and environmental adaptation have not been clearly elucidated. Here, we assembled a high integrity and good contiguity genome of Drung cattle with 13.7-fold contig N50 and 4.1-fold scaffold N50 improvements over the recently published Indian mithun assembly, respectively. Speciation time estimation and phylogenetic analysis showed that Drung cattle diverged from Bos taurus into an independent evolutionary clade. Sequence evidence of centromere regions provides clues to the breakpoints in BTA2 and BTA28 centromere satellites. We furthermore integrated a circulation and contraction-related biological process involving 43 evolutionary genes that participated in pathways associated with the evolution of the cardiovascular system. These findings may have important implications for understanding the molecular mechanisms of chromosome fusion, alpine valleys adaptability and cardiovascular function. Integrated genomic, transcriptomic, and methylomic data from the endangered Drung cattle (Bos frontalis) provide further insight into its unique physiology and adaptation to alpine environments. [ABSTRACT FROM AUTHOR]

PageRank is a widespread model for analysing the relative relevance of nodes within large graphs arising in several applications. In the current paper, we present a cost-effective Hessenberg-type method built upon the Hessenberg process for the solution of difficult PageRank problems. The new method is very competitive with other popular algorithms in this field, such as Arnoldi-type methods, especially when the damping factor is close to 1 and the dimension of the search subspace is large. The convergence and the complexity of the proposed algorithm are investigated. Numerical experiments are reported to show the efficiency of the new solver for practical PageRank computations. [ABSTRACT FROM AUTHOR]

The mineral composition of copper tailings was examined, and the phase analysis of gallium was conducted for recovery of the rare scattered metal gallium from copper tailings. The reaction characteristics and kinetics of gallium in the chlorination roasting of copper tailings were investigated in a tube furnace apparatus under different conditions, including roasting temperature, quantity of chlorination agent, roasting time, and airflow. Calcium chloride was chosen for the chlorination reaction because it is highly effective for volatilization of metals. The results show that gallium mainly exists in limonites in the form of oxides, and increases in roasting temperature, quantity of chlorination agent, and roasting time are conducive to increasing the chloridizing volatilization rate of gallium. The tailings gradually melt when the roasting temperature exceeds 900 °C, resulting in a decrease in the chloridizing volatilization rate of gallium. The chloridizing volatilization rate of gallium reaches 78.86 % at roasting temperature of 900 °C for 40 min, airflow of 0.1 m3·h−1, and calcium content of 33.33 wt%. Study of the reaction kinetics of gallium in chlorination roasting shows that the values of activation energy both for chemically controlled and diffusion-controlled reactions are 44.64 and 11.93 kJ·mol−1, respectively. This indicates that the chemical reaction serves an important function in the chlorination volatilization of gallium. Taken together, the results reveal the usefulness of tailings as a source of rare metals and provide a basis for gallium recovery and environmentally friendly disposal of copper tailings. [ABSTRACT FROM AUTHOR]

Metal halide perovskites based on MX6 (M is metal and X is halogen) octahedra have developed into significant materials, extensively used in many fields, such as solid-state lighting, semiconductor, and nonlinear optics. However, the MX5 square pyramid-based hybrid metal halides beyond zero-dimensional (0D) polyhedrons and clusters are rarely reported. Herein, we reported two new isostructural hybrid antimony halides, namely (2cepyH)SbCl4 (1-Cl) and (2cepyH)SbBr4 (2-Br) (2cepy = 1-(2-chloroethyl)pyrrolidine), characterized by 1D polar polyanionic chains formed by corner-sharing SbX5 tetragonal pyramid units. Upon photoexcitation at 340 nm, 1-Cl shows broad, yellow phosphorescence emissions stemming from triplet self-trapped excitons, as proved by its long lifetime (6.85 μs) and the temperature dependences of broadband emission. To our knowledge, this should be the first observation on the broadband emissive properties in the 1D hybrid metal halide constructed by MX5 tetragonal pyramid units. Moreover, second harmonic generation measurements show that the nonlinear optical properties of 2-Br (∼3.2 × KDP) are superior to that of 1-Cl (∼1.8 × KDP). Experimental and calculated data indicate that the bandgap of 1-Cl is larger than that of 2-Br and that the polar inorganic moieties determine their band structures. Our work opens up a new way for constructing broadband emission materials with novel polar frameworks. [ABSTRACT FROM AUTHOR]

In this article, our goal is to establish fast and efficient numerical methods for nonlinear space-fractional convection–diffusion–reaction (CDR) equations in the 1, 2, and 3 dimensions. For the spatial discretization of the CDR equations, the weighted essentially non-oscillatory (WENO) scheme is used to approximate the convection term, and the fractional centered difference formula is applied to deal with the diffusion term. As a result, a nonlinear system of ordinary differential equations (ODEs) is derived. Since implicit integration factor (IIF) methods are a class of time-stepping schemes with good robustness and stability, the second order IIF–WENO scheme on non-uniform meshes in Jiang and Zhang (J Comput Phys 253:368–388, 2013) is applied to solve the nonlinear ODEs system. In order to obtain an efficient implementation of the IIF–WENO scheme, we propose an adaptive restarting Krylov subspace method to compute the action of matrix exponentials arising in IIF–WENO. Numerical examples are presented to confirm the validity of the IIF–WENO scheme, and to verify that the proposed fast solution algorithm is extremely attractive in terms of computational complexity and memory storage. [ABSTRACT FROM AUTHOR]

The space fractional Cahn–Hilliard phase-field model is more adequate and accurate in the description of the formation and phase change mechanism than the classical Cahn–Hilliard model. In this article, we propose a temporal second-order energy stable scheme for the space fractional Cahn–Hilliard model. The scheme is based on the second-order backward differentiation formula in time and a finite difference method in space. Energy stability and convergence of the scheme are analyzed, and the optimal convergence orders in time and space are illustrated numerically. Note that the coefficient matrix of the scheme is a 2 × 2 block matrix with a Toeplitz-like structure in each block. Combining the advantages of this special structure with a Krylov subspace method, a preconditioning technique is designed to solve the system efficiently. Numerical examples are reported to illustrate the performance of the preconditioned iteration. [ABSTRACT FROM AUTHOR]

Volterra subdiffusion problems with weakly singular kernel describe the dynamics of subdiffusion processes well. The graded L1 scheme is often chosen to discretize such problems since it can handle the singularity of the solution near t = 0 . In this paper, we propose a modification. We first split the time interval [0, T] into [ 0 , T 0 ] and [ T 0 , T ] , where T 0 ( 0 < T 0 < T ) is reasonably small. Then, the graded L1 scheme is applied in [ 0 , T 0 ] , while the uniform one is used in [ T 0 , T ] . Our all-at-once system is derived based on this strategy. In order to solve the arising system efficiently, we split it into two subproblems and design two preconditioners. Some properties of these two preconditioners are also investigated. Moreover, we extend our method to solve semilinear subdiffusion problems. Numerical results are reported to show the efficiency of our method. [ABSTRACT FROM AUTHOR]

In recent years, more users tend to use data mining as a service (DMaaS) provided by cloud service providers. However, while enjoying the convenient pay-per-use mode and powerful capacity of cloud computing, users are also threatened by the potential risk of privacy leakage. In this paper, we aim to efficiently perform privacy-preserving DMaaS, and focus on frequent itemset mining over encrypted database in outsourced cloud environment. Existing work apply different encryption methods to design various privacy-preserving mining solutions. Nevertheless, these approaches either cannot provide sufficient security requirements, or introduce heavy computation costs. Some of them also need users staying on-line to execute computations, which are not practical in real-world applications. In this paper, we propose a novel efficient privacy-preserving frequent itemset query (PPFIQ) scheme using two homomorphic encryptions and ciphertext packing technique. The proposed scheme protects transaction database with semantic security, preserves mining privacy and resists frequency analysis attacks. Meanwhile, efficiency is guaranteed by inherent parallel computations for packed plaintexts and users could stay off-line during the mining process. We provide formal security analysis and evaluate the performance of our scheme with extensive experiments. The experiment results demonstrate that the proposed scheme can be efficiently implemented on large databases. [ABSTRACT FROM AUTHOR]

Develop a rat model of hilar cholangiocarcinoma for detecting bile salt export pump (Bsep) expression in hilar cholangiocarcinoma tissues, in order to provide a new therapeutic target for the gene therapy of hilar cholangiocarcinoma. Sixty male Wistar rats (body weight, 190 ± 8 g) were randomly divided into three groups (the experimental group, the control group and the sham operation group, n = 20 each) as follows: The three groups were fed a standard diet, the experimental group was injected by cholangiocarcinoma QBC939 cell suspension along the hilar bile duct into the bile duct bifurcation with microsyringe, the control group was injected by normal saline, the sham operation group did not inject anything. Every day assess the rats' mental state, diet, and motion by using Basso–Beattie–Bresnahan and combined behavioral score. At 4 weeks, one rat of the experimental group was sacrificed after it was administered anesthesia, and we recorded changes in hilar bile duct size, texture, and form. This procedure was repeated at 6 weeks. After 6 weeks, hilar cholangiocarcinoma developed only in the experimental group, thereby establishing an experimental model for studying QBC939-induced hilar cholangiocarcinoma. Tumor formation was confirmed by pathological examination, and hilar bile duct tissues were harvested from both the groups. A real-time polymerase chain reaction assay and an immunohistochemical assay were used to analyze the expression of Bsep in hilar bile duct tissues of each group. From the second week, the rats in experimental group began to eat less, and their body mass decreased compared with control group and sham operation group. After 6 weeks, we detected hilar cholangiocarcinoma in the hilar bile duct tissues of 18 rats (90%) in the experimental group. In the experimental group with hilar cholangiocarcinoma, we found that the levels of total cholesterol, total bilirubin, and direct bilirubin were higher compared with those in the control group and sham operation group. Simultaneously, muddy stones emerged from the bile ducts of rats in the experimental group. The Bsep/Gapdh mRNA ratio in hilar cholangiocarcinoma, control group and sham operation group differed markedly. Light microscopy revealed a granular pattern of Bsep protein expression which reacted with the anti-Bsep antibody. Each section was randomly divided into six regions, with 80 cells were observed in every region. Sections with > 10% positive cells were designated positive, Sections with < 10% positive cells were designated negative. Each group included 4800 cells. In the experimental group, 1200 cells (25%) were positive, in the control group, 3648 cells (76%) were positive and in the sham operation group 3598 cells (75%) were positive, and this difference was statistically significant. Bsep expression significantly decreased in hilar cholangiocarcinoma of rats than those in control group and sham operation group, suggesting that drugs targeting Bsep are a new strategy for hilar cholangiocarcinoma. [ABSTRACT FROM AUTHOR]