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Myeloperoxidase (MPO) is a mammalian pro‐oxidant protease and it is closely related to severe infections and diverse inflammatory diseases. Rapid and sensitive measurement of MPO activity is essential for anticancer drug discovery and inflammatory research. Herein, we demonstrate the construction of an oxidative cleavage‐activated deoxyribozymes (DNAzyme) biosensor for rapid detection and cellular imaging of the MPO activity. When target MPO is present, the phosphorothioate (PS)‐modified hairpin probe is site‐specifically cleaved by MPO, releasing the intact Mg2+‐dependent DNAzyme sequences. Subsequently, the activated DNAzyme initiates the cyclic cleavage of the signal probe with the assistance of cofactor Mg2+, liberating large numbers of Cy5 molecules. This assay possesses the characteristics of easy operation, low sample consumption, without the requirements of expensive radiolabeling, antibodies, and nanomaterials. Especially, this assay can be performed in one pot under isothermal conditions (37°C) within 60 min. Due to the high efficiency of DNAzyme‐based cyclic cleavage reaction and the intrinsic advantages of single‐molecule detection, this assay achieves high sensitivity with a limit of detection (LOD) of 2.74×10−3 ng μL−1. It can be applied to screen MPO inhibitors, measure cellular MPO activity at the single‐cell level, and image intracellular MPO in living cells, providing a powerful platform for early clinical diagnosis and drug discovery. [ABSTRACT FROM AUTHOR]

We have developed a simple and rapid mix-and-read assay for the sensitive detection of O6-methylguanine DNA methyltransferase (MGMT) activity based on exonuclease III-assisted signal amplification under completely isothermal conditions (37 °C). This method is very simple and rapid (60 min) with ultrahigh sensitivity and good specificity, and it can detect MGMT activity at the single-cell level. Moreover, this method can be applied for the screening of MGMT inhibitors and the discrimination of MGMT in different cancer cells. [ABSTRACT FROM AUTHOR]

Small-sized fuel cell has tremendous potential and broad market prospect in the field of portable devices, but its hydrogen source with compact structure and stable and high purity hydrogen supply remains an issue for commercialization. In this research, a novel in situ hydrogen production material Al–BiCl 3 composite is developed via ball milling method, and its hydrogen production performance is evaluated in terms of induction time, storage stability, hydrogen production rate and hydrogen yield. The results demonstrate that Al–BiCl 3 has excellent hydrogen production performance and its hydrogen yield can reach 85 % within 2.3 h. During ball milling process, many surface cracks and active surface are produced and some BiCl 3 is reduced to metal Bi by Al, resulting in the high hydrolysis activity of Al–BiCl 3. Prolonging milling time can promote the formation of surface cracks and Bi, enhancing the activity of Al–BiCl 3. The hydrogen production mechanisms of Al–BiCl 3 are attributed to pitting and microgalvanic effect between Al and Bi. Taking into account hydrogen production performance, cost and safety, Al-10 wt% BiCl 3 milled for 1 h is a suitable and potential in situ hydrogen production material for small-sized fuel cells. [Display omitted] • Al–BiCl 3 composite was prepared and its H 2 production performance was evaluated. • Al–BiCl 3 composite has no induction time and its H 2 yield can reach 85 % within 2.3 h. • AlOOH can increase H 2 yield and recover the reactivity of Al–BiCl 3 stored in air. • Pitting and microgalvanic effect were the H 2 production mechanisms of Al–BiCl 3. • Al-10 wt% BiCl 3 is a promising H 2 production material for small-sized fuel cells. [ABSTRACT FROM AUTHOR]

Fat mass and obesity-associated protein (FTO) is a crucial eraser of RNA N6- methyladenosine (m6A) modification, and abnormal FTO expression level is implicated in pathogenesis of numerous cancers. Herein, we demonstrate the construction of a label-free fluorescent biosensor for homogeneous detection of m6A eraser FTO in breast cancer tissues. When FTO is present, it specifically erases the methyl group in m6A, inducing the cleavage of demethylated DNA by endonuclease Dpn II and the generation of a single-stranded DNA (ssDNA) with a 3′-hydroxyl group. Subsequently, terminal deoxynucleotidyl transferase (TdT) promotes the incorporation of dTTPs into the ssDNA to obtain a long polythymidine (T) DNA sequence. The resultant long poly (T) DNA sequence can act as a template to trigger hyperbranched strand displacement amplification (HSDA), yielding numerous DNA fragments that may be stained by SYBR Gold to produce an enhanced fluorescence signal. This biosensor processes ultrahigh sensitivity with a detection limit of 1.65 × 10−10 mg/mL (2.6 fM), and it can detect the FTO activity in a single MCF-7 cell. Moreover, this biosensor can screen the FTO inhibitors, evaluate enzyme kinetic parameters, and discriminate the FTO expression levels in the tissues of breast cancer patients and healthy persons. [Display omitted] • We construct a new biosensor for label-free detection of FTO activity. • This biosensor exhibits high sensitivity and good specificity. • This biosensor can detect the FTO activity in a single MCF-7 cell. • It can screen inhibitors and measure enzyme the kinetic parameters. • It can discriminate breast cancer tissues from healthy person tissues. [ABSTRACT FROM AUTHOR]

Invited for this month's cover is the collaborating group of Prof. Chun‐Yang Zhang at Southeast University, China and colleagues at Shandong Normal University. The cover picture shows the formation of oxidative cleavage‐activated DNAzyme that enables imaging of myeloperoxidase in living cells. More information can be found in the Research Article by Zi‐Yue Wang, Chun‐Yang Zhang, and co‐workers. [ABSTRACT FROM AUTHOR]

In this work, we analytically and experimentally present a perfect and broadband acoustic insulation waveguide composed of gradient impedance boundaries. With these designed impedance boundaries, the incident plane wave will be converted into the surface wave mode and be absorbed or reflected back. The transmission rate reaches nearly zero in a broadband (1800–7000 Hz, typically), and the bandwidth is adjustable to fit different noise spectra. Our results may contribute more possible designs for noise reduction challenges in the waveguide. [ABSTRACT FROM AUTHOR]

DNA glycosylase assumes a pivotal role in the preservation of genome integrity by recognizing and excising damaged bases. Herein, we develop a single primer/self-template-powered cascade rolling circle amplification (RCA) and apurinic/apyrimidinic endonuclease (APE1)-mediated signal amplification for simultaneous detection of human alkyladenine DNA glycosylase (hAAG) and uracil DNA glycosylase (UDG). The uniqueness of this approach lies in the use of custom-designed hairpin probes to establish a prerequisite for RCA: the conformational change of hairpin probe to circular template, which effectively suppress undesired non-specific amplification. We design two hairpin probes featuring elongated stem structure and 3′-phosphate (3′-PO 4) modifications. The stems of hairpin probes are modified with glycosylase substrates and BER process can cleave hairpin probes, resulting in the generation of single-stranded DNAs (ssDNAs) with 3′-hydroxyl (3′-OH) ends. These ssDNAs can function as padlock probes to form circular template upon ligation by ligase. Ultimately, the self-template-initiated RCA and APE1-mediated signal amplification cascade occurs, generating a substantial number of free Cy3 and Cy5 fluorophores that can be simply visualized by single-molecule fluorescence detection. This method demonstrates excellent specificity and sensitivity, with a limit of detection (LOD) of 3.42 × 10-12 U/μL for hAAG and 2.41 × 10-12 U/μL for UDG. This method also can be used for screening of potential inhibitor and kinetic parameter measurement. Most importantly, this method enables accurate profiling of glycosylases expression levels in various cancer cell lines and detection of glycosylase activities at the single-cell level, offering a bright future in cancer detection, medical research, and precision medicine. • Simultaneous detection of multiple glycosylases at ultra-low concentrations. • Conformation-switchable hairpin probes and self-templated amplification reduce non-specific amplification. • One primer probe can simultaneously trigger two isothermal amplifications. • Accurate assessment of DNA glycosylase expression in different cancer cell lines. [ABSTRACT FROM AUTHOR]

An acoustic one-way device plays an important role in acoustic wave regulation. However, traditional one-way structures mainly discuss the unidirectional behavior of acoustic energy and often suffer from changes in mode or frequency. Here, we propose an acoustic one-way waveguide device with acoustic soft boundaries in which a special wave pattern filter is constructed. The numerical and experimental results show that acoustic waves can pass through the acoustic waveguide device efficiently in the positive direction without any wave pattern change and can be totally reflected back in the negative direction. The effective cascade of two one-way waveguide devices is also realized. Our work may provide a practical and efficient approach to the innovative design possibilities in the fields of acoustic wave regulation and computing devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • We demonstrate simultaneous single-molecule detection of FTO and ALKBH3. • Only a single DNA ligase can achieve multi-cyclic cascade amplification. • This method exhibits high sensitivity and good specificity. • This method can screen inhibitors and detect cellular RNA demethylases. • This method can discriminate breast cancer patients from healthy persons. RNA demethylases play a crucial role in gene expression regulation by controlling RNA methylation levels, and their abnormal expressions are associated with many human diseases. Herein, we develop a single-molecule detection method for simultaneous quantification of N6-methyladenosine (m6A) demethylase FTO and N1-methyladenosine (m1A) demethylase ALKBH3 based on RNA demethylation-directed multi-cyclic ligase chain reaction (LCR) cascades. We design a ssDNA containing m6A modification as the substrate of FTO and a ssDNA containing m1A modification as the substrate of ALKBH3. FTO and ALKBH3 catalyze the demethylation of m6A and m1A to generate normal adenine (A), respectively. Afterwards, Taq ligase initiates the LCR reaction with the demethylated ssDNAs as the templates to produce abundant biotinylated Cy3/Cy5-labeled signal probes. Subsequently, the resultant biotinylated probes are captured by streptavidin-coated magnetic beads (MBs) to form the MB-ssDNA-Cy3/Cy5 complexes. After magnetic separation, the ssDNAs in the MB-ssDNA-Cy3/Cy5 complexes are digested by DNase I, liberating abundant Cy3 and Cy5 fluorophores that can be counted by single-molecule detection. Remarkably, only a single DNA ligase is employed to achieve target signal conversion and multi-cyclic cascade amplification. This method displays extremely high sensitivity with a limit of detection of 6.33 × 10−18 mol/L for FTO and 1.44 × 10−17 mol/L for ALKBH3. Moreover, it can measure the enzyme kinetic parameters, screen inhibitors, and quantify cellular FTO and ALKBH3 activities with single-cell sensitivity. Furthermore, it can differentiate the FTO and ALKBH3 levels in the tissues of healthy human and breast cancer patients, offering a robust platform for biomedical research and clinical diagnosis. [ABSTRACT FROM AUTHOR]

Summary: Because of the frequent breakdown of major resistance (R) genes, identification of new partial R genes against rice blast disease is an important goal of rice breeding. In this study, we used a core collection of the Rice Diversity Panel II (C‐RDP‐II), which contains 584 rice accessions and are genotyped with 700 000 single‐nucleotide polymorphism (SNP) markers. The C‐RDP‐II accessions were inoculated with three blast strains collected from different rice‐growing regions in China. Genome‐wide association study identified 27 loci associated with rice blast resistance (LABRs). Among them, 22 LABRs were not associated with any known blast R genes or QTLs. Interestingly, a nucleotide‐binding site leucine‐rich repeat (NLR) gene cluster exists in the LABR12 region on chromosome 4. One of the NLR genes is highly conserved in multiple partially resistant rice cultivars, and its expression is significantly up‐regulated at the early stages of rice blast infection. Knockout of this gene via CRISPR‐Cas9 in transgenic plants partially reduced blast resistance to four blast strains. The identification of this new non‐strain specific partial R gene, tentatively named rice blast Partial Resistance gene 1 (PiPR1), provides genetic material that will be useful for understanding the partial resistance mechanism and for breeding durably resistant cultivars against blast disease of rice. [ABSTRACT FROM AUTHOR]

Objectives. To investigate whether Helicobacter pylori (H. pylori) infection increases the risk of colorectal adenomatous polyp (CAP) in the context of age and gender. Methods. A total of 563 study subjects (male/female, 368/195) from Beijing, China, with higher nursing level who underwent colonoscopy were retrospectively collected. H. pylori and CAP were detected by carbon-13 urea breath test and colorectal colonoscopy. The correlations between the number, size, distribution, and pathological grade of CAP and H. pylori infection were analyzed. The population was further stratified by age and gender in order to examine the risk of H. pylori and CAP in the context of these variables. The influence of H. pylori on the risk of CAP was assessed by logistic regression model. Results. 315 participants were diagnosed with CAP, and 207 participants were classified as healthy controls. The prevalence of H. pylori in the CAP group was significantly higher than that in the healthy control group (119/315, 37.8% versus 44/207, 21.3%) (p < 0.001). The proportion of H. pylori positive plus CAP in participants <50 years old was significantly higher than that in participants >50 years old (87/250; 34.8% versus 32/65; 49.2%) (p = 0.033). Furthermore, H. pylori infection was identified as one of the major risk factors of CAP (OR = 2.679 ; 95% CI: 1.717-4.179, p < 0.001), independent of age, sex, and body mass index and was correlated with size, distribution, and pathological grading of CAP (p < 0.001). Conclusions. H. pylori is a major risk factor for CAP. Further studies are needed to assess the effects of H. pylori treatment or persistent infection on the occurrence or recurrence of CAP. [ABSTRACT FROM AUTHOR]

The METTL3/14 complex is an important RNA N6-Methyladenosine (m6A) methyltransferase in organisms, and the abnormal METTL3/14 complex activity is associated with the pathogenesis and various cancers. Sensitive detection of METTL3/14 complex is essential to tumor pathogenesis study, cancer diagnosis, and anti-cancer drug discovery. However, traditional methods for METTL3/14 complex assay suffer from poor specificity, costly antibodies, unstable RNA substrates, and low sensitivity. Herein, we construct a single quantum dot (QD)-based förster resonance energy transfer (FRET) biosensor for sensitive detection of METTL3/14 complex activity. In the presence of METTL3/14 complex, it catalyzes the methylation of adenine in the substrate probe, leading to the formation of m6A that protects the substrate probes from MazF-mediated cleavage. The hybridization of methylated DNA substrate with biotinylated capture probe initiates polymerization reaction to obtain a biotinylated double-stranded DNA (dsDNA) with the incorporation of numerous Cy5 fluorophores. Subsequently, the Cy5-incorporated dsDNA can self-assembly onto the 605QD surface to form the 605QD-dsDNA-Cy5 nanostructure, causing FRET between 605QD donor and Cy5 acceptor. This biosensor has excellent sensitivity with a limit of detection (LOD) of 3.11 × 10−17 M, and it can measure the METTL3/14 complex activity in a single cell. Moreover, this biosensor can be used to evaluate the METTL3/14 complex kinetic parameters and screen potential inhibitors. Furthermore, it can differentiate the METTL3/14 complex expression in healthy human tissues and breast cancer patient tissues, providing a powerful tool for cancer pathogenesis study, clinical diagnosis, prognosis monitoring, and drug discovery. We develop a single quantum dot-based förster resonance energy transfer (FRET) biosensor for sensitive detection of METTL3/14 complex activity in breast cancer tissues. [Display omitted] • We develop a single quantum dot-based FRET biosensor. • This biosensor can sensitively detect the METTL3/14 complex activity. • It can measure the METTL3/14 complex activity in a single cell. • This biosensor can evaluate kinetic parameters and screen inhibitors. • It can discriminate breast cancer patient tissues from healthy tissues. [ABSTRACT FROM AUTHOR]

The spin accumulation and the out-of-plane spin current in two-dimensional (x-y plane) electron gas with the Rashba spin-orbit interaction are examined. Employing the real-space Landauer–Keldysh Green’s function formalism and considering the two-terminal Landauer setup with leads locally contacting the sample, we show that the accumulation patterns for the three components of the spins can be identified from their unique symmetries. With increasing lateral sample length, the out-of-plane spin accumulation oscillates by generating bubbles with alternating signs on the lateral edges. The out-of-plane spin currents are patterned by global vortices, and within the locally biased region of the sample, the direction of the current flow also oscillates as a function of the lateral sample length. [ABSTRACT FROM AUTHOR]

The spin-Hall effect in the two-dimensional electron gas (2DEG) generates symmetric out-of-plane spin Sz accumulation about the current axis in the absence of external magnetic field. Here we employ the real space Landauer-Keldysh formalism [B. K. Nikolic et al., Phys. Rev. Lett. 95, 046601 (2005); Phys. Rev. B 73, 075303 (2006)] by considering a four-terminal setup to investigate the circumstances in which this symmetry is broken. For the absence of Dresselhaus interaction, starting from the applied out-of-plane B corresponding to Zeeman splitting energy Δ=0–0.5 times the Rashba hopping energy tSOR, the breaking process is clearly seen. The influence of the Rashba interaction on the magnetization of the 2DEG is studied herein. For coexisted Rashba tSOR and Dresselhaus tSOD spin-orbit couplings in the absence of B, interchanging tSOR and tSOD reverses the entire accumulation pattern. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new chemiluminescent biosensor is constructed for poly (ADP-ribose) polymerase-1 (PARP-1) assay. • This biosensor is characterized by electrostatic force independence and rapidity. • This biosensor can screen PARP-1 inhibitors and quantify PARP-1 at single-cell level. • This biosensor can rapidly detect PARP-1 in human breast tissues. Poly (ADP-ribose) polymerase-1 (PARP-1) is a multi-domain nuclear enzyme that mediates gene transcription and DNA repair. Accurate detection of PARP-1 is essential to clinical diagnostic. However, conventional PARP-1 assays rely on electrostatic force with the involvement of lengthy and complex construction processes and false positive. Herein, we construct an ultrasensitive chemiluminescent biosensor for rapid detection of PARP-1 in human breast tissues by integrating PARP-1-directed hyperbranched poly(ADP-ribose) (PAR) formation with alkaline phosphatase (ALP)-3-(2′-spiroadamantyl)-4-methoxy-4- (3′'-phosphoryloxyphenyl)-1,2-dioxetane (AMPDD)-mediated chemiluminescence system. Upon activation by dsDNA, PARP-1 cleaves nicotinamide adenine dinucleotide (NAD+), initiating the repeated polymerization of biotinylated ADP-ribose to form the dsDNA- PAR-biotin complex. The subsequent assembly of dsDNA-PAR-biotin complexes onto AuNPs through Au-S covalent bond results in the construction of the AuNPs-dsDNA-biotin nanostructure. AuNPs-dsDNA-biotin nanostructure subsequently captures SA-ALP to form the AuNPs-dsDNA-ALP nanostructure. After centrifugation and separation, the AuNPs-dsDNA-ALP nanostructure initiates the dephosphorylation of AMPPD to produce a high chemiluminescent signal. In this assay, only PARP-1 activated by dsDNA can cleave NAD+, efficiently eliminating background signal. The introduction of frozen method greatly shortens the assay time. Benefiting from high precision of the PARP-1-catalyzed NAD+ cleavage, high efficiency of biotinylated ADP-ribose polymerization reaction, and high signal-to-noise ratio of ALP-AMPPD chemiluminescence system, this biosensor can rapidly and sensitively detect PARP-1 with a detection limit of 2.94 × 10−7 U/μL, accurately screen PARP-1 inhibitors, and quantify PARP-1 at single-cell level. Most importantly, it can differentiate PARP-1 expression between breast cancer patient tissues and healthy person tissues, with promising applications in clinical diagnosis and biomedical research. [ABSTRACT FROM AUTHOR]

Background Atherosclerosis (AS) is the most common and serious complication of type 2 diabetes mellitus (T2DM) and is accelerated via chronic systemic inflammation rather than hyperglycemia. Adipose tissue is the major source of systemic inflammation in abnormal metabolic state. Pro-inflammatory CD4 + T cells play pivotal role in promoting adipose inflammation. Adipose-derived stem cells (ADSCs) for fat regeneration have potent ability of immunosuppression and restricting CD4 + T cells as well. Whether T2DM ADSCs are impaired in antagonizing CD4 + T cell proliferation and polarization remains unclear. Methods We constructed type 2 diabetic ApoE −/− mouse models and tested infiltration and subgroups of CD4 + T cell in stromal-vascular fraction (SVF) in vivo . Normal/T2DM ADSCs and normal splenocytes with or without CD4 sorting were separated and co-cultured at different scales ex vivo. Immune phenotypes of pro- and anti-inflammation of ADSCs were also investigated. Flow cytometry (FCM) and ELISA were applied in the experiments above. Results CD4 + T cells performed a more pro-inflammatory phenotype in adipose tissue in T2DM ApoE −/− mice in vivo . Restriction to CD4 + T cell proliferation and polarization was manifested obviously weakened after co-cultured with T2DM ADSCs ex vivo . No obvious distinctions were found in morphology and growth type of both ADSCs. However, T2DM ADSCs acquired a pro-inflammatory immune phenotype, with secreting less PGE2 and expressing higher MHC-II and co-stimulatory molecules (CD40, CD80). Normal ADSCs could also obtain the phenotypic change after cultured with T2DM SVF supernatant. Conclusion CD4 + T cell infiltration and pro-inflammatory polarization exist in adipose tissue in type 2 diabetic ApoE −/− mice. T2DM ADSCs had impaired function in restricting CD4 + T lymphocyte proliferation and pro-inflammatory polarization due to immune phenotypic changes. [ABSTRACT FROM AUTHOR]

Chirality is one of the key features governing the electronic properties of single- and bilayer graphene: the basics of this concept and its consequences on transport are presented in this review. By breaking the inversion symmetry, a band gap can be opened in the band structures of both systems at the K-point. This leads to interesting consequences for the pseu-dospin and, therefore, for the chirality. These consequences can be accessed by investigating the evolution of the Berry phase in such systems. Experimental observations of Fabry-Pérot interference in a dual-gated bilayer graphene device are finally presented and are used to illustrate the role played by the band gap on the evolution of the pseudospin. The presented results can be attributed to the breaking of the chirality in the energy range close to the gap. (© 2015 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Telomerase is an important reverse transcriptase that is in charge of maintaining telomeres length, and the dysregulation of telomerase activity is closely associated with cancers. Accurate measurement of telomerase activity is critical to clinical diagnosis and therapeutics. Herein, by taking advantage of in vivo repair mechanisms and single-molecule detection, we demonstrate the enzymatic DNA repair cascade-driven fluorophore encoding for sensitively sensing telomerase activity in cancer cells. The presence of telomerase enables repetitive addition of (TTAGGG) n to the 3′-OH end of telomerase substrate (TS) primer to generate long telomeric products. Telomeric product then hybridizes with the apurinic (AP) probe to induce the cleavage of AP site in dsDNA by APE1, yielding a ssDNA with a biotin and an OH group at 5′ and 3′ ends and simultaneously releasing the telomeric product which in turn hybridizes with new AP probes to yield numerous ssDNAs. By adding streptavidin-coated MBs, the ssDNAs are captured and subsequently functioned as primers to initiate template-free TdT-catalyzed random incorporation of dATPs and Cy5-dATPs into 3′-OH ends, producing long poly-A chains with multiple Cy5 molecules encoding and finally forming Cy5-ssDNA-MB complexes. After magnetic separation, Cy5-ssDNA-MBs are digested by Exo I, releasing large numbers of Cy5 molecules which can be measured by single-molecule detection. This strategy exhibits excellent specificity and high sensitivity with a limit of detection (LOD) of 1 cancer cell. Moreover, it can be employed to screen inhibitors and discriminate different cancer cell lines from normal cell lines, holding enormous potential in clinical diagnosis and therapeutics. • We demonstrate the enzymatic DNA repair cascade-driven fluorophore encoding for sensing telomerase activity. • This method is based on in vivo repair mechanism and single-molecule detection. • This method exhibits good specificity. • This method exhibits high sensitivity with a limit of detection of 1 cancer cell. • This method can be employed to screen inhibitors and discriminate cancer cell lines from normal cell lines. [ABSTRACT FROM AUTHOR]

Ten-eleven translocation (TET) family proteins play key roles in multiple cellular processes by mediating the oxidation of 5-methylcytosine to directly participate in DNA demethylation, and often aberrantly expressed in various diseases. In this research, we develop a single-quantum-dot (QD)-mediated fluorescence resonance energy transfer (FRET) biosensor for amplification-free measurement of ten-eleven translocation 2 (TET2). When TET2 is present, it catalyzes the oxidation of 5-vinylcytosine in dsDNA to 5-formylmethylcytosine, and the subsequent labeling of dsDNA with Cy5 generates a biotinylated Cy5-dsDNA complex. Biotinylated Cy5-dsDNA complexes are conjugated to the streptavidin-coated 605QDs to obtain a Cy5-dsDNA-605QD nanostructures, inducing FRET from 605QD to Cy5. FRET signal can be simply measured by single-molecule counting. This biosensor enables homogeneous detection of TET2 with a limit of detection (LOD) of 0.042 ng/μL, and it can accurately measure cellular TET2 down to 1 cell. Moreover, this biosensor can be used to screen TET2 inhibitors, offering a new platform for TET2-related medical research and clinical diagnostics. We develop a single quantum dot (QD)-mediated fluorescence resonance energy transfer (FRET) biosensor for amplification-free detection of ten-eleven translocation 2. [Display omitted] • A single-quantum-dot-mediated FRET biosensor is developed for sensitive detection of ten-eleven translocation 2 (TET2). • FRET signal can be quantitatively measured by single-molecule detection. • This biosensor enables homogeneous and sensitive detection of TET2 with a limit of detection of 0.042 ng/μL. • This biosensor can accurately measure cellular TET2 down to 1 cell. • This biosensor can be used to screen TET2 inhibitors. [ABSTRACT FROM AUTHOR]

Abstract: We present a theoretical method to calculate the expectation value of spin in an inversion-asymmetric two-dimensional (2D) system with respect to an arbitrarily spin-polarized electron state, injected via an ideal point contact. The 2D system is confined in a [001]-grown quantum well, where both the Rashba and the Dresselhaus spin–orbit couplings are taken into account. The obtained analytical results allow more concrete description of the spatial behaviors of the spin precession caused individually by the Rashba and the Dresselhaus terms. Applying the calculation on the Datta–Das spin-FET, whose original design considers only the Rashba effect inside the channel, we investigate the possible influence due to the Dresselhaus spin–orbit coupling. Concluded solution is the choice of ±[1±10], in particular [110], as the channel direction. [Copyright &y& Elsevier]

Background. Previous studies have suggested a link between Helicobacter pylori (H. pylori) infection and nonalcoholic fatty liver disease (NAFLD), yet long-term follow-up studies to elucidate this association are lacking. We aimed to identify the relationship between NAFLD and H. pylori in these people. Methods. A total of 2,934 adults between June 2013 and October 2017 were collected; among them, 675 people met the requirements. People were assessed for H. pylori infection diagnosis as detected by the carbon-13 urea breath test; they were also assessed for NAFLD diagnosis by ultrasound. Results. H. pylori infection was present in 206 patients (30.5%), and 469 (69.5%) participants were classified as controls. Participants with H. pylori infection had a higher rate of incident NAFLD than those who were uninfected (37/206; 18% versus 73/469; 15.6%) (p < 0.001). Compared with the control group, the recovery rate of NAFLD in the H. pylori+ve group was low (6/206, 2.9% versus 33/469, 7.0%) (p < 0.001). Besides, the incidence of uric acid, postprandial blood glucose, TG, LDL-C, HDL-C, and fasting plasma glucose was significantly different between the two groups (p < 0.001), but no difference was found in alanine aminotransferase (ALT), liver-total protein, urea nitrogen, and cholesterol (p > 0.05). Conclusion. H. pylori infection was a risk factor for NAFLD and affected the occurrence or reversal of NAFLD, indicating that H. pylori infection eradication might play a role in reducing the risk of NAFLD. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented discussing complications regarding the formation of steinstrasse in a 47-year-old man with pancreatic stones after being treated with extracorporeal shock wave lithotripsy (ESWL).

We report a broadband acoustic energy harvesting metasurface consisting of periodic arrangements of coupled Helmholtz resonators. Theoretical analysis and numerical and experimental results show that a high output voltage can be obtained at a wide band (460 Hz–680 Hz) under the push-pull effect on the piezoelectric composite sheet (PCS) between the two coupled cavities, which is because the acoustic pressure phases in the two coupled cavities are nearly opposite to each other. Each output can be directly connected in parallel without any rectification circuit because the output voltage from every PCS has the same phase on account of the symmetry of the proposed metasurface. The proposed design has an efficient and easy-to-integrate structure, and it can be used in broad applications for acoustic energy harvesting devices and acoustic insulators. [ABSTRACT FROM AUTHOR]

The article presents a case study of 73-year old female who was presented with severe abdominal pain. The patient's endoscopic retrograde cholangiopancreatography report shows presence of residual mucus in the bile duct responsible for the complications. The images depicting computed tomography report of the patient which shows dilation of bile duct is also included.

A letter to the editor is presented in response to an article related to the prevalence of duodenal polyps in patients and who are referred for upper endoscopy in the previous issue.

No abstract is available for this article. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both US and AH greatly enhanced hydrogen production performance of Al hydrolysis. • US and AH increased v max from 6.8 to 33.0 and 28.0 ml·min−1·g−1-Al, respectively. • For AH + US, induction time was 0.17 h and v max was as high as 66.0 ml·min−1·g−1-Al. • AH + US exhibited the best performance due to synergistic effect between AH and US. Ultrasound can accelerate and change the reaction process and is widely used in the field of hydrogen production and storage. In this study, ultrasound (US) and AlOOH suspension (AH) are used to promote hydrogen production from Al hydrolysis. The results indicate that both US and AH greatly shorten the induction time and enhance the hydrogen production rate and yield. The promoting effect of US and AH on Al hydrolysis originates from the acoustic cavitation effect and catalytic effect, respectively. When AH is used in combination with US, Al hydrolysis has the best hydrogen production performance and the hydrogen yield can reach 96.6 % within 1.2 h, because there is a synergistic effect on Al hydrolysis between AH and US. Mechanism analyses reveal that the micro-jets and local high temperature environment arising from acoustic cavitation improve the catalytic activity of AlOOH, while the suspended AlOOH particles enhance the cavitation effect of US. This work provides a novel and feasible method to promote hydrogen production from Al hydrolysis. [ABSTRACT FROM AUTHOR]

Electrostatic superlattices have been known to significantly modify the electronic structure of low-dimensional materials. Studies of graphene superlattices were triggered by the discovery of moiré patterns in van der Waals stacks of graphene and hexagonal boron nitride (hBN) layers a few years ago. Very recently, gate-controllable superlattices using spatially modulated gate oxides have been achieved, allowing for Dirac band structure engineering of graphene. Despite these rapid experimental progresses, technical advances in quantum transport simulations for large-scale graphene superlattices have been relatively limited. Here, we show that transport experiments for both graphene/hBN moiré superlattices and gate-controllable superlattices can be well reproduced by transport simulations based on a scalable tight-binding model. Our finding paves the way to tuning-parameter-free quantum transport simulations for graphene superlattices, providing reliable guides for understanding and predicting novel electric properties of complex graphene superlattice devices. The electronic structure of graphene can be modified by applying the so-called superlattice potential, arising either from interfacing with hexagonal boron nitride lattices or gate capacitance with spatially periodic modulation, giving rise to a range of unusual transport behavior. Here, the authors report a simulation method to reproduce transport experiments, showing consistent transmission spectra and mini-band structures for graphene superlattices. [ABSTRACT FROM AUTHOR]

We investigate the quality of hydrogen plasma defined graphene edges by Raman spectroscopy, atomic resolution AFM and low temperature electronic transport measurements. The exposure of graphite samples to a remote hydrogen plasma leads to the formation of hexagonal shaped etch pits, reflecting the anisotropy of the etch. Atomic resolution AFM reveals that the sides of these hexagons are oriented along the zigzag direction of the graphite crystal lattice and the absence of a D-peak within the noise background in the Raman spectra seems to suggest rather high quality zigzag edges. In a second step of the experiment, we investigate hexagon edges created in single layer graphene on hexagonal boron nitride and find a substantial D-peak intensity. Polarization dependent Raman measurements reveal that hydrogen plasma defined edges consist of a mixture of zigzag and armchair segments. Furthermore, electronic transport measurements were performed on hydrogen plasma defined graphene nanoribbons which indicate a high quality of the bulk but a relatively low edge quality, in agreement with the Raman data. These findings are supported by tight-binding transport simulations. Hence, further optimization of the hydrogen plasma etching technique is required to obtain pure crystalline graphene edges. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Background Androgen has been implicated in aging-related cardiac remodeling, but its precise role in aging heart remains controversial. We aimed to investigate the role of testosterone in the development of aging-related cardiac remodeling and the mechanisms involved. Methods Wild type and Axl knockout mice (Axl−/−) were randomized into three groups: the young group (n = 30, 3 months old), the aging group (n = 30, 18 months old), the testosterone undecanoate treatment group (TU, n = 30, 18 months old). Mice in the TU group were given testosterone undecanoate (39 mg/kg) by subcutaneous injection on the back at fifteen-months-old, once a month, a total of three times. The old group received solvent reagent (corn oil) by the same method. Results The aging mice exhibited a decrease in serum testosterone, and Gas6 levels and an increase in apoptosis, and manifested cardiac fibrosis. Testosterone injection to wild type mice increased the levels of testosterone and Gas6 in serum and decreased cardiac apoptosis and fibrosis. Axl−/−mice receiving testosterone injection exhibited no obvious improvement in cardiac remodeling although the levels of testosterone and Gas6 in serum elevated. Conclusions These data indicated that testosterone replacement therapy (TRT) alleviates cardiac fibrosis and apoptosis, at least in part by enhancing Gas6 expression. Moreover, deletion of Axl disables testosterone, which indicated that Axl is an important downstream regulator of testosterone. TRT would improve aging-related cardiac remolding via Gas6/Axl signaling pathway, implicating its therapeutic potential to treat aging-related heart disease. Highlights • Testosterone decreases cardiomyocyte apoptosis in aging mice. • Testosterone ameliorates cardiac fibrosis in aging mice. • Testosterone increases the level of Gas6. • Testosterone protects from cardiac aging in a Gas6/Axl dependent manner. [ABSTRACT FROM AUTHOR]

While Fabry-Pérot (FP) resonances and Moiré superlattices are intensively studied in graphene on hexagonal boron nitride (hBN), the two effects have not been discussed in their coexistence. Here we investigate the FP oscillations in a ballistic pnp-junctions in the presence and absence of a Moiré superlattice. First, we address the effect of the smoothness of the confining potential on the visibility of the FP resonances and carefully map the evolution of the FP cavity size as a function of densities inside and outside the cavity in the absence of a superlattice, when the cavity is bound by regular pn-junctions. Using a sample with a Moiré superlattice, we next show that an FP cavity can also be formed by interfaces that mimic a pn-junction but are defined through a satellite Dirac point due to the superlattice. We carefully analyze the FP resonances, which can provide insight into the band-reconstruction due to the superlattice. [ABSTRACT FROM AUTHOR]