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Theoretical predictions of laser beam interactions with jet-engine-exhaust-induced turbulence are of importance for optimization of various optical systems, including LIDARs and airborne laser measurement systems. This paper is based on the extended Huygens–Fresnel diffraction integral and the Wigner distribution function, combined with the recently proposed power spectral density function of atmospheric turbulence induced by jet engine exhaust, to derive the formula for the quality factor of a partially coherent Airy beam in turbulent media induced by jet engine exhaust. Numerical calculations based on the analytical formula show that the smaller the structure constant and outer scale of the atmospheric turbulence induced by jet engine exhaust, the smaller the quality factor of a partially coherent Airy beam, indicating better laser beam quality. At the same time, the larger the generalized parameter and inner scale of the jet-engine-exhaust-induced turbulence and the longer the wavelength of the laser beam, the smaller the corresponding quality factor. The numerical results also show that reducing the coherence length of a partially coherent Airy beam and increasing its characteristic width are beneficial for reducing the quality factor in the atmospheric turbulence induced by jet engines. However, the numerical results show that increasing the coherence length of a partially coherent Airy beam and reducing its characteristic width are beneficial for reducing the quality factor in vacuum. This situation demonstrates significant differences between the interaction mechanisms of an Airy beam in vacuum and in the jet-engine-exhaust-induced turbulence. The results of our discussion contribute to clarifying the mechanism of interaction between an Airy laser beam and random media, as well as the application of a curved Airy laser beam in practical situations. [ABSTRACT FROM AUTHOR]

The self‐assembled hole transporting molecules (SAHTMs) bearing anchoring groups have been established as the hole transporting layers (HTLs) for highly efficient p–i–n perovskite solar cells (PSCs), yet their stability and engineering at the molecular level remain challenging. A topological design of highly anisotropic aligned SAHTM‐based HTLs for operationally stable PSCs that exhibit exceptional solar‐to‐electric power conversion efficiencies (PCEs) is demonstrated. The judiciously designed multifunctional self‐assembled molecules comprise the donor–acceptor subunit for hole transporting and the phosphonic acid group for anchoring, realizing face‐on π‐stacking parallel to the transparent conductive oxide substrate. The high affinity of SAHTMs to the multi‐crystalline perovskite thin film benefits passivating the perovskite buried interface, strengthening interfacial contact while facilitating interfacial hole transfer. Consequently, highly efficient p–i–n PSC devices are obtained with a champion PCE of 23.24% and outstanding operational stability toward various environmental factors including long‐term full sunlight soaking at evaluated temperatures. Perovskite solar modules with a champion efficiency approaching 20% are also fabricated for an active device area above 17 cm2. [ABSTRACT FROM AUTHOR]

Additional sex combs-like 1 (ASXL1) is an epigenetic modulator frequently mutated in myeloid malignancies, generally associated with poor prognosis. Current models for ASXL1-mutated diseases are mainly based on the complete deletion of Asxl1 or overexpression of C-terminal truncations in mice models. However, these models cannot fully recapitulate the pathogenesis of myeloid malignancies. Patient-derived induced pluripotent stem cells (iPSCs) provide valuable disease models that allow us to understand disease-related molecular pathways and develop novel targeted therapies. Here, we generated iPSCs from a patient with myeloproliferative neoplasm carrying a heterozygous ASXL1 mutation. The iPSCs we generated exhibited the morphology of pluripotent cells, highly expressed pluripotent markers, excellent differentiation potency in vivo, and normal karyotype. Subsequently, iPSCs with or without ASXL1 mutation were induced to differentiate into hematopoietic stem/progenitor cells, and we found that ASXL1 mutation led to myeloid-biased output and impaired erythroid differentiation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that terms related to embryonic development, myeloid differentiation, and immune- and neural-related processes were most enriched in the differentially expressed genes. Western blot demonstrated that the global level of H2AK119ub was significantly decreased when mutant ASXL1 was present. Chromatin Immunoprecipitation Sequencing showed that most genes associated with stem cell maintenance were upregulated, whereas occupancies of H2AK119ub around these genes were significantly decreased. Thus, the iPSC model carrying ASXL1 mutation could serve as a potential tool to study the pathogenesis of myeloid malignancies and to screen targeted therapy for patients.Graphical Abstract: Additional sex combs-like 1 (ASXL1) is an epigenetic modulator frequently mutated in myeloid malignancies, generally associated with poor prognosis. Current models for ASXL1-mutated diseases are mainly based on the complete deletion of Asxl1 or overexpression of C-terminal truncations in mice models. However, these models cannot fully recapitulate the pathogenesis of myeloid malignancies. Patient-derived induced pluripotent stem cells (iPSCs) provide valuable disease models that allow us to understand disease-related molecular pathways and develop novel targeted therapies. Here, we generated iPSCs from a patient with myeloproliferative neoplasm carrying a heterozygous ASXL1 mutation. The iPSCs we generated exhibited the morphology of pluripotent cells, highly expressed pluripotent markers, excellent differentiation potency in vivo, and normal karyotype. Subsequently, iPSCs with or without ASXL1 mutation were induced to differentiate into hematopoietic stem/progenitor cells, and we found that ASXL1 mutation led to myeloid-biased output and impaired erythroid differentiation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed that terms related to embryonic development, myeloid differentiation, and immune- and neural-related processes were most enriched in the differentially expressed genes. Western blot demonstrated that the global level of H2AK119ub was significantly decreased when mutant ASXL1 was present. Chromatin Immunoprecipitation Sequencing showed that most genes associated with stem cell maintenance were upregulated, whereas occupancies of H2AK119ub around these genes were significantly decreased. Thus, the iPSC model carrying ASXL1 mutation could serve as a potential tool to study the pathogenesis of myeloid malignancies and to screen targeted therapy for patients. [ABSTRACT FROM AUTHOR]

By fast heating the nano‐sized Al2O3 and carbon black mixtures at 50°C/min to 1750°C for 30–120 min, single‐phase AlON powders were successfully obtained by a fast one‐step carbothermal reduction and nitridation (CRN) method. The AlON ceramics pressureless sintered at 1880°C for 150 min by these powders show high transmittances up to 83%–84%, which indicates that the proposed fast one‐step CRN method is an effective and efficient way with strong robustness to synthesize single‐phase AlON powder for highly transparent AlON ceramics. It was found that α‐Al2O3 particles do not have enough time to aggregate and coalesce during heating due to the tremendously shortened heating span, which significantly inhibited particle coarsening until the formation of AlON starts. The fast‐formed AlON further inhibits the coarsening of α‐Al2O3 during dwelling. Consequently, single‐phase AlON powder of small primary particles can be obtained after 30 min dwelling at 1750°C. [ABSTRACT FROM AUTHOR]

Exposure to nickel, an environmental respiratory toxicant, is associated with lung diseases including asthma, pulmonary fibrosis, bronchitis and cancers. Our previous studies have shown that a majority of the nickel-induced transcriptional changes are persistent and do not reverse even after the termination of exposure. This suggested transcriptional memory, wherein the cell 'remembers' past nickel exposure. Transcriptional memory, due to which the cells respond more robustly to a previously encountered stimulus has been identified in a number of organisms. Therefore, transcriptional memory has been described as an adaptive mechanism. However, transcriptional memory caused by environmental toxicant exposures has not been well investigated. Moreover, how the transcriptional memory caused by an environmental toxicant might influence the outcome of exposure to a second toxicant has not been explored. In this study, we investigated whether nickel-induced transcriptional memory influences the outcome of the cell's response to a second respiratory toxicant, nicotine. Nicotine, an addictive compound in tobacco, is associated with the development of chronic lung diseases including chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis. Our results show that nicotine exposure upregulated a subset of genes only in the cells previously exposed to nickel. Furthermore, our analyses indicate robust activation of interferon (IFN) signaling in these cells. IFN signaling is a driver of inflammation, which is associated with many chronic lung diseases. Therefore, our results suggest that nicotine exposure of lung cells that retain the transcriptional memory of previous nickel exposure could result in increased susceptibility to developing chronic inflammatory lung diseases. • This study investigates the consequences of nickel-induced transcriptional memory. • Nicotine upregulated a unique set of genes only in the cells previously exposed to nickel. • Nicotine activated IFN signaling in the cells that retain the memory of previous nickel exposure. [ABSTRACT FROM AUTHOR]

Hexavalent chromium [Cr(VI)] is a potent human lung carcinogen. Multiple mechanisms have been proposed that contribute to Cr(VI)-induced lung carcinogenesis including oxidative stress, DNA damage, genomic instability and epigenetic modulation. However, the molecular mechanisms and pathways mediating Cr(VI) carcinogenicity have not been fully elucidated. Hedgehog (Hh) signaling is a key pathway that plays important roles in the formation of multiple tissues during embryogenesis and in the maintenance of stem cell populations in adults. Dysregulation of Hh signaling pathway has been reported in many human cancers. Here, we report a drastic reduction in both mRNA and protein levels of hedgehog‐interacting protein (HHIP), a downstream target and a negative regulator of Hh signaling, in Cr(VI)-transformed cells. These findings point to a potential role of Hh signaling in Cr(VI)-induced malignant transformation and lung carcinogenesis. Cr(VI)-transformed cells exhibited DNA hypermethylation and silencing histone marks in the promoter region of HHIP , indicating that an epigenetic mechanism mediates Cr(VI)-induced silencing of HHIP. In addition, the major targets of Hh signaling (GLI1-3 and PTCH1) were significantly increased in Cr(VI)-transformed cells, suggesting an aberrant activation of Hh signaling in these cells. Moreover, ectopically expressing HHIP not only suppressed Hh signaling but also inhibited cell proliferation and anchorage-independent growth in Cr(VI)-transformed cells. In conclusion, these findings establish a novel regulatory mechanism underlying Cr(VI)-induced lung carcinogenesis and provide new insights for developing a better diagnostic and prognostic strategy for Cr(VI)-related human lung cancer. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a known human lung carcinogen. In addition, Cd exposure is associated with several lung diseases including emphysema, chronic obstructive pulmonary disease (COPD), asthma and fibrosis. Although earlier studies have identified several processes dysregulated by Cd exposure, the underlying mechanisms remain unclear. Here, we examined the transcriptome of lung epithelial cells exposed to Cd to understand the molecular basis of Cd-induced diseases. Computational analysis of the transcriptome predicted a significant number of Cd-upregulated genes to be targets of miR-30 family miRNAs. Experimental validation showed downregulation of all the miR-30 family members in Cd exposed cells. We found SNAIL, an EMT master regulator, to be the most upregulated among the miR-30 targets. Furthermore, we found decrease in the levels of epithelial marker E - cadherin (CDH1) and increase in the levels of mesenchymal markers, ZEB1 and vimentin. This suggested induction of EMT in Cd exposed cells. Luciferase reporter assays showed that miR-30 repressed SNAIL by directly targeting its 3′ UTR. Over expression of miR-30e and transfection of miR-30e mimics reduced Cd-induced SNAIL upregulation. Our results suggest that miR-30 negatively regulates SNAIL in lung epithelial cells and that Cd-induced downregulation of miR-30 relieves this repression, resulting in SNAIL upregulation and EMT induction. EMT plays a major role in many diseases associated with Cd exposure including fibrosis, COPD, and cancer and metastasis. Therefore, our identification of miR-30 downregulation in Cd exposed cells and the consequent activation of SNAIL provides important mechanistic insights into lung diseases associated with Cd exposure. • A number of genes upregulated by Cd exposure are targets of miR-30 family miRNAs. • miR-30 family is downregulated in Cd exposed BEAS-2B and BEP2D cells. • Cd induced miR-30 repression caused upregulation of the EMT master regulator, SNAIL. • miR-30e overexpression and miR30e mimics prevented Cd-induced SNAIL upregulation. [ABSTRACT FROM AUTHOR]

A novel method for study the interaction between carbohydrate and lectin was developed in homogenous solution. DNA was introduced to the recognition process of carbohydrate with protein. Due to the versatile detection mode of DNA, the detection efficiency for carbohydrate and protein was highly promoted. Herein, two kinds of mannose-DNA conjugates were synthesized. One of which was used to prepare DNA-templated silver nanocluster (AgNCs) and the other one contained guanine-rich DNA sequences. When the mannose of two conjugates binding to lectin Concanavalin A (Con A), great enhancement on fluorescence intensity was obtained due to the proximity ligation of the DNA-templated Ag NCs with guanine-rich DNA sequences. Hence Con A can be quantified conveniently in homogenous solution using Ag NCs with low toxicity and tunable fluorescence. Moreover, carbohydrate functionalized DNA-templated AgNCs was also utilized for cancer cell imaging based on the recognition of mannose with mannose receptor on cancer cell MDA-MB-231. [ABSTRACT FROM AUTHOR]

Except the tunable photoluminescent property, graphene quantum dots (GQDs) with special structures have also exhibited other novel properties. Herein, GQDs played a novel coreactant role in Ru(bpy) 3 2+ /GQDs system to increase the anodic ECL signal of Ru(bpy) 3 2+ , which has been testified by ultraviolet, fluorescence, and electrochemiluminescence (ECL) experiments. Based on the coreactant mechanism of Ru(bpy) 3 2+ /GQDs system, a chlorinated phenol-related quenching ECL sensor was designed and the sensor showed a good linear relationship in the range from 0.60 to 55 μM with the detection limit of 1.4 × 10 −8 M (S/N = 3). These results were not only beneficial to resolve the structure of GQDs, but also expanded the application field of GQDs. [ABSTRACT FROM AUTHOR]

Both nickel and cadmium compounds have been established as group I carcinogens for several decades. Despite over-whelming evidence of these compounds’ carcinogenicity in humans, the specific underlying molecular mechanisms that govern metal induced cellular transformation remain unclear. In this study, we found that there were slightly different effects on decreased SLBP mRNA and protein as well as increased polyA H3.1 in our nickel exposed cells. This suggested that nickel and arsenic have similar effects on canonical histone mRNA transcription and translation. We also saw that the depletion of SLBP protein was reversed by inhibiting the proteosome. Finally, we showed that inhibiting the SLBP mRNA and protein levels were rescued by epigenetic modifiers suggesting that nickel’s effects on SLBP may be mediated via epigenetic mechanisms. Taken together these results suggest a similar mechanism by which both arsenic and nickel may exert their carcinogenic effects. [ABSTRACT FROM AUTHOR]

To quantify the physical/chemical properties, and the formation and growth processes of aerosol particles on mountainous regions in Southeast China, an intensive field campaign was conducted from April to July 2008 on the top of Mt. Huang (1840 m above mean sea level). The average particle number concentration was 2.35 × 10 3 cm − 3 , and the ultrafine particles (< 0.1 μm) represented 70.5% of the total particle number concentration. Excluding the accumulation mode particles, the average daytime particle number concentrations were prominently higher than those measured at nighttime, suggesting there was a diurnal pattern of changes between planetary boundary layer and free troposphere air. The aerosol spectra were classified into two categories: the first category (FCS) exhibited a clear diurnal cycle, with relatively higher number concentration (3.19 × 10 3 cm − 3 ), smaller sizes and air masses from the inland; the second category (SCS) presented less obvious diurnal cycle, with lower number concentration (1.88 × 10 3 cm − 3 ), larger sizes and air masses from coastal regions. Air mass sources, weather conditions, and new particle formation (NPF) events were responsible for the differences of these two particle spectra. Six NPF events were identified, which usually began at 10:00–11:00 LT, with the estimated formation rate J 10 in the range of 0.09–0.30 cm − 3 s − 1 and the growth rate at 1.42–4.53 nm h − 1 . Wind speed, sulfur dioxide and ozone concentrations were higher on NPF days than those on non-NPF days, whereas temperature, relative humidity, concentrations of nitrogen oxide and carbonic oxide were lower on NPF days. Sulfur dioxide and ozone might be main potentially precursor gases for those NPF events. The NPF events at Mt. Huang corresponded closely to a southwest winds. These results are useful for improving our understanding of the main factors controlling the variation of aerosol size distribution and NPF events in this region. [ABSTRACT FROM AUTHOR]

[Display omitted] • TPA-BA modification results in improved interfacial energy band alignment. • TPA-BA modification reduces interfacial chemical reactivity. • The TPA-BA-modified devices achieve a power conversion efficiency of 22.25%. • TPA-BA-based devices remained stable after illumination and thermal aging tests. Nickel oxide (NiO x) is one of the most promising inorganic hole transport layers for perovskite solar cells (PSCs) due to its low cost, high hole mobility, and superior stability. However, the mismatched energy level and undesirable chemical reaction at the NiO x /perovskite interface limit the performance of NiO x -based PSCs. Herein, a p- type semiconductor TPA-BA is explored to modify the NiO x /perovskite interface and form an intermediate hole transport layer (HTL) between NiO x and perovskite for efficient and efficient stable PSCs. This molecule comprises triphenylamine and carboxyl function groups, which can be anchored on the NiOx surface and facilitate the hole transfer between the perovskite and NiO x layer by minimizing the interfacial band energy offset. Furthermore, the bi-layered NiO x HTL exhibited reduced chemical reactivity at NiO x /perovskite interface, which would otherwise lead to detrimental perovskite degradation. Thus, a champion PSC device with an open-circuit voltage value up to 1.15 V and a power conversion efficiency of 22.25% was demonstrated-a high value for NiO x -based PSCs. More importantly, the intermediated HTL modified PSCs exhibit significantly improved device stability compared with un-modified PSCs, retaining over 90 % of their initial efficiencies after 1000-h continuous operation under 1 sun illumination and thermal aging at 85 °C respectively. This work renders the promise of TPA-BA as the intermediated HTL in between p -type metal oxide and perovskite for optoelectronic applications. [ABSTRACT FROM AUTHOR]

Ultraviolet radiation (UVR) from sunlight is the primary effector of skin DNA damage. Chromatin remodeling and histone post-translational modification (PTM) are critical factors in repairing DNA damage and maintaining genomic integrity, however, the dynamic changes of histone marks in response to solar UVR are not well characterized. Here we report global changes in histone PTMs induced by solar simulated UVR (ssUVR). A decrease in lysine acetylation of histones H3 and H4, particularly at positions of H3 lysine 9, lysine 56, H4 lysine 5, and lysine 16, was found in human keratinocytes exposed to ssUVR. These acetylation changes were highly associated with ssUVR in a dose-dependent and time-specific manner. Interestingly, H4K16ac, a mark that is crucial for higher order chromatin structure, exhibited a persistent reduction by ssUVR that was transmitted through multiple cell divisions. In addition, the enzymatic activities of histone acetyltransferases were significantly reduced in irradiated cells, which may account for decreased global acetylation. Moreover, depletion of histone deacetylase SIRT1 in keratinocytes rescued ssUVR-induced H4K16 hypoacetylation. These results indicate that ssUVR affects both HDAC and HAT activities, leading to reduced histone acetylation. [ABSTRACT FROM AUTHOR]

Salvia miltiorrhiza is a traditional Chinese herbal medicine, whose quality and yield are often affected by diseases and environmental stresses during its growing season. Salicylic acid (SA) plays a significant role in plants responding to biotic and abiotic stresses, but the involved regulatory factors and their signaling mechanisms are largely unknown. In order to identify the genes involved in SA signaling, the RNA sequencing (RNA-seq) strategy was employed to evaluate the transcriptional profiles in S. miltiorrhiza cell cultures. A total of 50,778 unigenes were assembled, in which 5,316 unigenes were differentially expressed among 0-, 2-, and 8-h SA induction. The up-regulated genes were mainly involved in stimulus response and multi-organism process. A core set of candidate novel genes coding SA signaling component proteins was identified. Many transcription factors (e.g., WRKY, bHLH and GRAS) and genes involved in hormone signal transduction were differentially expressed in response to SA induction. Detailed analysis revealed that genes associated with defense signaling, such as antioxidant system genes, cytochrome P450s and ATP-binding cassette transporters, were significantly overexpressed, which can be used as genetic tools to investigate disease resistance. Our transcriptome analysis will help understand SA signaling and its mechanism of defense systems in S. miltiorrhiza. [ABSTRACT FROM AUTHOR]

Cation-exchange-based chemiluminescence amplification (CXCLAmp) was developed in this study. After amplification by rolling circle amplification (RCA), the proposed RCA–CXCLAmp strategy was used to detect miRNA sensitively. [ABSTRACT FROM AUTHOR]

Abstract: Tumor-associated carbohydrate antigens (TACAs) are often found on the surface of cancer cells. The determination of the carbohydrate components of glycoconjugates is challenging because of the chemical complexity of glycan chains. Through monitoring corresponding antibody, we can get a good solution for clinical diagnosis. Here breast tumor-associated carbohydrate antigens Tn were used as a model and a new photoelectrochemical biosensor for ultrasensitive detection of antibody against Tn was developed. To enhance the sensitivity, both graphene oxide and graphene were used during the construction of biosensor. Through the formation of immunocomplex and the insoluble biocatalytic precipitation (BCP) product, photocurrent intensity was decreased greatly and the antibody could be detected from 0.5 to 500pg/mL with a detection limit of 1.0×10−13 g/mL. At the same time, the developed biosensor showed acceptable selectivity and could be used in the complex matrix. Compared with the traditional glycoarray method, this PEC method is more sensitive (5 orders of magnitude), and thus provides another platform to monitor the immune response to carbohydrate epitopes at different stages during differentiation, metastasis, or treatment. [Copyright &y& Elsevier]

Abstract: A new photoelectrochemical (PEC) biosensor was developed using low-toxic Ag2S QDs as photoelectrochemically active species. Energy levels of Ag2S and Ag2Se QD were compared to explain their differences in the PEC performance. The preparation condition of Ag2S QD was optimized and its structure characterization was measured. Then the developed photoelectric active interface was used to detect glucose and MCF-7 cancer cell and showed the good sensitivity and specificity. Under optimal condition, detection limits of 3.2×10−5 M for glucose and 98cells/mL for MCF-7 cell were achieved. Thus, the prepared Ag2S QD could serve as an excellent and promising photoelectric active material in the PEC biosensor. [Copyright &y& Elsevier]

Abstract: We report a strategy for the transduction of DNA hybridization into a readily detectable photoelectrochemical signal by means of a conformational change analogous to electrochemical DNA (E-DNA) approach. To demonstrate the effect of distance change for photosensitizer to the surface of electrode on the change of photocurrent, photosensitizer Ru(bpy)2(dcbpy)2+ tagged DNA stem–loop structures were self-assembled onto a nanogold modified ITO electrode. Hybridization induced a large conformational change in DNA structure, which in turn significantly altered the electron-transfer tunneling distance between the electrode and photosensitizer. The resulting change in photocurrent was proportional to the concentration of DNA in the range of 1.0×10−10–8.0×10−9 M. In order to improve the sensitivity of the photoelectrochemical biosensor, an amplified detection method based on isothermal strand displacement polymerization reaction was employed. With multiple rounds of isothermal strand replication, which led to strand displacement and constituted consecutive signal amplification, a detection limit of 9.4×10−14 M target DNA was achieved. [Copyright &y& Elsevier]

A new photoelectrochemical (PEC) biosensor was developed by using carboxyl-functionalized graphene and CdSe nanoparticles. This sensitive interface was then successfully applied to detection of thrombin based on the dual-quenched effect of PEC nanoparticle, which relied on the electron transfer of a bipyridinium relay and energy transfer of AuNPs. After recognition with an aptamer, the PEC nanoparticle was removed and a signal-on PEC biosensor was obtained. Moreover, the bio-barcode technique used in the preparation of PEC nanoparticle could avoid cross-reaction and enhances the sensitivity. Taking advantages of the various methods mentioned above, the sensitivity could be easily enhanced. In addition, in this work we also investigated graphene that was modified with different functional groups and AuNPs of different particle sizes. Under optimal conditions, a detection limit of 5.9×10−15 M was achieved. With its simplicity, selectivity, and sensitivity, this strategy shows great promise for the fabrication of highly efficient PEC biosensors. [ABSTRACT FROM AUTHOR]

Abstract: A label-free photoelectrochemical cytosensor for highly sensitive and specific detection of Ramos cell was developed based on photoactive films. The films were fabricated by a layer-by-layer (LBL) assembly of positively charged poly(dimethyldiallylammonium chloride) (PDDA) and negatively charged CdSe semiconductor nanoparticles (NPs) capped with mercaptoacetic acid. The resulting modified electrodes were tested as sensors for Ramos cell through the recognition of DNA aptamer which was covalently bound to the electrode using the classic coupling reactions between –COOH groups on the surfaces of CdSe NPs and –NH2 groups of the aptamer. The newly developed cytosensor exhibited excellent sensitivity and selectivity. The linear range was from 160 to 1600cells/mL and the detection limit was 84cells/mL. [Copyright &y& Elsevier]

Abstract: Nanosized TiO2 photocatalysts of anatase, rutile and mixed-phase were synthesized through hydrolysis method. The influence of the interface junction between anatase and rutile TiO2 on the photo-generated charge carriers properties were studied by Kelvin probe (KP), surface photovoltage (SPV) and transient photovoltage (TPV) techniques. The KP results revealed that the difference of the surface work function between anatase and rutile might cause the formation of built-in field at the interface in mixed-phase TiO2. The role of the interface junction was further testified through the characteristics of photo-generated charge carriers by SPV and TPV. [Copyright &y& Elsevier]

Abstract: Physical light source is absolutely necessary for usual photoelectrochemical measurement. In this work, chemiluminescence reaction rather than physical light source was used for the development of a novel photoelectrochemical DNA biosensor. CIPO (bis(2,4,5-trichlro-6-n-pentoxycarbonylphenyl)oxalate)–H2O2–9,10-diphenylanthrancene was selected as a CL system, which can produce appropriate exciting light and excite photoelectro active materials Ru(bpy)2dppz2+ intercalated into the double-stranded DNA. Using such simple intercalation method, a detection limit of 4.5×10−9 M target DNA was achieved without any amplification process. In addition, the selected CL system could be used to excite AuNPs–Ru(bpy)2dppz2+ complex as well as CdSe QD multilayer, which indicated a good applicability for the established method. [ABSTRACT FROM AUTHOR]

Abstract: Different sizes of ZnWO4 photocatalysts were synthesized by a hydrothermal method. The as-prepared sample shows highly efficient photocatalytic activity for the degradation of RhB under UV irradiation, which significantly vary with the increase of the hydrothermal temperatures. Surface photovoltage spectrum (SPS), field-induced surface photovoltage spectrum (FI-SPS) and surface photovoltage transient (TPV) techniques are used to investigate the detailed photoinduced charge transfer behavior. Results indicate that the ZnWO4 synthesized at 413K possess the largest BET surface area and the abundant donor surface states which are assumed to inhibit the recombination of the photogenerated electron–hole pairs, and thus a significant enhancement in the reaction rate is observed. [Copyright &y& Elsevier]

Abstract: A novel “signal-on” assay for sensitive and selective detection of Hg2+ in aqueous solution based on mismatched DNA and a molecular light switch complex, [Ru(phen)2(dppz)]2+, was reported in the present work. This Hg2+ specific sensor system composed of two label-free DNA probes with eight T–T mismatches, which could form stable DNA duplexes by thymine–Hg2+–thymine (T–Hg2+–T) in the presence of Hg2+. The luminescence of [Ru(phen)2(dppz)]2+ is very weak in aqueous solution, and significant luminescence can be observed when intercalating into DNA duplexes. By monitoring Hg2+-dependent luminescence intensity enhancement, highly sensitive and selective determination of Hg2+ has been achieved. Under the optimum conditions, the luminescence intensity was proportional to the concentration of Hg2+ in the range of 1.0×10−9–1.5×10−7 M. A detection limit of 3.5×10−10 M Hg2+ was achieved using 3σ. The presence of other metal ions did not interfere with the detection of Hg2+ even at high concentrations. This approach is simple and rapid, which can be used to monitor the Hg2+ concentration in drinking water and natural media within 30min. [Copyright &y& Elsevier]

Abstract: In the present study, an electrochemical aptasensor for highly sensitive detection of thrombin was developed based on bio-barcode amplification assay. For this proposed aptasensor, capture DNA aptamerI was immobilized on the Au electrode. The functional Au nanoparticles (DNA–AuNPs) are loaded with barcode binding DNA and aptamerII. Through the specific recognition for thrombin, a sandwich format of Au/aptamerI/thrombin/DNA–AuNPs was fabricated. After hybridization with the PbSNPs-labeled barcode DNA, the assembled sensor was obtained. The concentration of thrombin was monitored based on the concentration of lead ions dissolved through differential pulse anodic stripping voltammetric (DPASV). Under optimum conditions, a detection limit of 6.2×10−15 molL−1 (M) thrombin was achieved. In addition, the sensor exhibited excellent selectivity against other proteins. [Copyright &y& Elsevier]

Abstract: A sensitive label-free bio-barcode assay provided a PCR-free method for quantitative detection of two nucleic acid targets (HTLV-I and HTLV-II) simultaneously. This DNA biosensor was fabricated with two-component oligonucleotide-modified gold nanoparticles (AuNPs) and two-component oligonucleotide-modified magnetic beads (MBs), which can sandwich a specific target. After liberating the adsorbed thiolated barcode DNA strands (poly A and poly G) from the AuNPs surface with dithiothreitol (DTT) and acidic dipurinization, the electrochemical measurements were directly performed based on the redox activity of guanine (G) and adenine (A) nucleobases. Under the optimal assembling and detection conditions, a good linearity for simultaneous detection was obtained in the range from 4.4×10−11 to 2.0×10−9 M, and the detection limit (3σ) was estimated to be 1.71×10−12 M for T1-DNA and 1.55×10−12 M for T2-DNA. [Copyright &y& Elsevier]

Several 1,2,3-triazole-linked glycoconjugates were efficiently synthesized via a Cu(I)-mediated 1,3-dipolar cycloaddition with high regiospecificity and yield (≥ 85%), providing a simple and efficient route to synthesize protected and unprotected neoglycoconjugates. Introduction of a spacer between glycosyl moieties and other compounds reduces steric hindrance, promotes yield, and expands the varieties of glycoconjugates to satisfy various needs of biological events. The structures of all the synthesized glycoconjugates were clearly confirmed by infrared(IR), 1H NMR, 13C NMR, elemental analysis (EA), or MS. [ABSTRACT FROM AUTHOR]

A novel hemoglobin (Hb) biosensor based on the remarkable synergistic effects of cerium dioxide (CeO2) and multiwalled carbon nanotubes (MWNTs) for detection of hydrogen peroxide (H2O2) is presented. The Hb/CeO2/MWNTs/CHIT nanocomposite was nanoengineered by selected matched material components and optimized composition ratio to produce a superior H2O2 sensor. The preparation method is quite simple and practical. This composite matrix combined the advantages of MWNTs, CeO2 nanoparticles, and chitosan (CHIT), with good electron-transfer ability, attractive biocompatibility, and fine film-forming ability, which could increase Hb attachment quantity and H2O2 detection sensitivity. In the optimum pH 7.0 phosphate buffer, the electrocatalytic response exhibited a linear dependence on H2O2 concentration in a wide range from 5.0 × 10-6 to 4.6 × 10-4 mol L-1 with a detection limit of 6.5 × 10-7 mol/L (3σ). [ABSTRACT FROM AUTHOR]

The Ugi four-component reaction (U-4CR) was utilized to prepare divalent and trivalent cluster mannosides with different scaffolds. The glycoclusters obtained were tested for their relative inhibitory potency against the binding of yeast mannan to concanavalin A by solid-phase enzyme-linked lectin assays (ELLA) using methyl α-d-mannopyranoside as a standard. Among them, a divalent mannoside containing aromatic groups showed the strongest binding affinity to concanavalin A. [Copyright &y& Elsevier]

• Three pathways contributed to ROS accumulation in yeast while being exposed to TCBPA. • TCBPA activated NADPH oxidase through regulation of three pathways. • TCBPA promoted expressions of genes which are responsible for ROS accumulation. • These results clarified that how TCBPA induced ROS accumulation in S. cerevisiae. Tetrachlorobisphenol A (TCBPA) can promote intracellular reactive oxygen species (ROS) accumulation. However, limited attention has been given to mechanisms underlying TCBPA exposure-associated ROS accumulation. Here, such mechanisms were explored in the simple eukaryotic model organism Saccharomyces cerevisiae exposed to multiple concentrations of TCBPA. Addition of diphenyleneiodonium, a specific inhibitor of NADPH oxidase, blocked TCBPA treatment-associated intracellular ROS accumulation. NADPH oxidase can be activated by calcineurin, mitogen-activated protein kinase (MAPK), and tyrosine kinase. Therefore, corresponding specific inhibition respectively on these three kinases was performed and results suggested that the Ca2+ signaling pathway, MAPK pathway, and tyrosine kinase pathway all contributed to the TCBPA exposure-associated intracellular ROS accumulation. In addition, TCBPA exposure-associated up-regulation of genes involved in ROS production and down-regulation of catalase promoted ROS accumulation in S. cerevisiae. To sum up, our current results provide insights into the understanding of TCBPA exposure-associated ROS accumulation. [ABSTRACT FROM AUTHOR]

Seven different conversion coatings (which can be classified into three types: MgP, ZnP and CaP) were prepared on Mg alloy substrates to compare the corrosion resistance and biocompatibility of these coatings. Biocompatibility and cytotoxicity of different coated samples and bare Mg alloy were studied using the CCK-8 test. The corrosion resistance of different conversion coatings was comparatively studied by electrochemical tests (OCP, EIS and PDP) and long-term immersion test in Hanks' solution. Based on the experimental results, the corrosion mechanism of different types of conversion coatings and Mg alloy substrate was proposed and investigated. Unlabelled Image • In this work, seven kinds of conversion coatings (which can be classified into three types of MgP, ZnP and CaP) were prepared by changing the content of Mg2+, Zn2+ and Ca2+ ions in conversion solutions. • The conversion coating generation priority was proposed: ZnP type > CaP type > MgP type. • The anti-corrosion performance of different coated samples are systematically investigated in Hanks' solution, and corrosion mechanisms different coatings are proposed from the perspective of filiform and pitting corrosion. • The biocompatibility and biodegradability of different conversion coatings and bare Mg alloy were investigated. • A "time constant shielding (TCS)" effect was proposed to explain the interaction between conductive loops and inductive loops in the EIS plot. [ABSTRACT FROM AUTHOR]

Trehalose could protect the typical food microorganism Saccharomyces cerevisiae cell against environmental stresses; however, the other regulation effects of trehalose on yeast cells during the fermentation are still poorly understood. In this manuscript, different concentrations (i.e., 0, 2 and 5% g/v) of trehalose were respectively added into the medium to evaluate the effect of trehalose on growth, central metabolisms and division of S. cerevisiae CEN.PK113-7D strain that could uptake exogenous trehalose. Results indicated that addition of trehalose could inhibit yeast cell growth in the presence or absence of 8% v/v ethanol stress. Exogenous trehalose inhibited the glucose transporting efficiency and reduced intracellular glucose content. Simultaneously, increased intracellular trehalose content destroyed the steady state of trehalose cycle and caused the imbalance between the upper glycolysis part and the lower part, thereby leading to the dysfunction of glycolysis and further inhibiting the normal yeast cell growth. Moreover, energy metabolisms were impaired and the ATP production was reduced by addition of trehalose. Finally, exogenous trehalose-associated inhibition on yeast cell growth and metabolisms delayed cell cycle. These results also highlighted our knowledge about relationship between trehalose and growth, metabolisms and division of S. cerevisiae cells during fermentation. • Exogenous trehalose could inhibit S. cerevisiae CEN.PK113-7D cell growth. • Trehalose inhibited the glucose transporting efficiency of S. cerevisiae cells. • Trehalose caused imbalance between upper glycolysis part and lower part. • Exogenous trehalose impaired the energy metabolisms of S. cerevisiae cells. • Exogenous trehalose could delay yeast cell cycle. [ABSTRACT FROM AUTHOR]

A photoelectrochemical sensing strategy for highly sensitive detection of thrombin was developed based on a layer-by-layer (LBL) assembly of functionalized graphene and CdSe nanoparticles. [ABSTRACT FROM AUTHOR]

A photoelectrochemical sensing strategy for highly sensitive detection of small molecules was developed based on the recognition interaction between aptamer and target molecule—ATP. [ABSTRACT FROM AUTHOR]

A chemiluminescence (CL) probe of peroxidase-like dicopper complex (Cu2L2) for the determination of glutathione (GSH) and related cellular thiols was developed for the first time. [ABSTRACT FROM AUTHOR]

A cathodic photoelectrochemical sensor has been developed for the determination of exosomes, based on a dual-signal reduction strategy. A heterostructure of NiO/BiOI/Au NP/CdSe was synthesized as a photoelectrochemical sensing interface, which is able to suppress the recombination of electron-hole pairs and produce a higher photocurrent. The obtained materials were characterized, and the mechanism for the generation of the cathodic photocurrent was proposed. CdSe QDs (quantum dots) modified with DNA2 were assembled on the electrode through the hybridization with EpCAM aptamer on the surface of ITO/NiO/BiOI/Au NP. The introduction of CdSe QDs to the electrode increases the photocurrent.The recognition of exosomes with aptamer DNA led to the separation of CdSe QDs from the electrode, which in turn caused the decrease of photocurrents. Meanwhile, the big volume of exosomes hinders the electron transfer between the electrode and electrolyte. Due to the dual reduction effect, a sensitive PEC sensor was obtained with a detection limit of 1.2 × 102 particles/μL exosomes (λex = 430 nm, bias voltage = − 0.1 V). The cathodic photoelectrochemical sensor showed good selectivity, performed well in a complex biological environment and could be used to distinguishbreast cancer patients from healthy individuals. [ABSTRACT FROM AUTHOR]

Air pollution is an important trigger of cardiovascular disease worldwide, but few studies have determined the cardiovascular disease, health, and economic burdens attributable to ambient carbon monoxide (CO). This study aimed to examine the association between CO and CVD hospitalizations, and quantified the attributable CVD hospitalizations, associated hospital stays and hospitalization costs for CO in Lanzhou, one of the most air-polluted Chinese cities historically. Daily data on CVD hospitalizations, air pollutants, and weather records from 2013 to 2017 were obtained for Lanzhou, China. Generalized additive model with a quasi-Poisson link was used to model the association between CO and CVD hospitalizations, after controlling for other air pollutants, weather conditions, day of week, long-term trend, influenza and pneumonia incidence. The effects of CO on hospital stays and hospitalization expenses from CVD were also quantified. CO concentrations below the current Chinese ambient air quality standard had a significant impact on CVD hospitalizations. Each 1 mg/m3 increase in CO concentration on the present day and previous 4 days (lag 0–4) was associated with an 11% (95% confidence interval: 3%–20%) increase in total CVD hospitalizations. During the study period, CO was responsible for 11.74% of total CVD hospitalizations, equating to 62,792 inpatient days and 149 million RMB. Each adult patient on average spent approximately 5% of annual salary on medicine from CO-related CVD treatment during hospitalization. Maintaining the historical CO concentration within 1 to 3 mg/m3 could avert hundreds of total CVD hospitalizations and save millions of RMB annually in Lanzhou, China. Exposure to low-level ambient CO concentration increased the risk of CVD hospitalizations and resulted in substantial health and economic burdens in Lanzhou, China. Our findings can be used for evidence-based practice and policy making to assess the cost-effectiveness of prevention measures. Unlabelled Image • We estimated the disease, health, and economic burdens of carbon monoxide (CO) on CVD. • Exposure to low-level CO still had adverse effects on CVD hospitalizations in Lanzhou, China. • Low-level CO caused substantial CVD hospitalizations, hospital stays, and hospitalization expenses. • Each adult patient spent around 5% of annual salary on medicine for CO-related CVD treatment. • Further control of CO could prevent massive CVD hospitalizations and save millions RMB annually. [ABSTRACT FROM AUTHOR]

Abstract In this work, the microstructures and mechanical properties of as-cast Mg-xHo-2Zn (x = 4, 6 and 8 wt%) alloys have been studied by using optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and tensile test at different temperatures. The Ho element exhibits an influence on the grain refinement of the alloys. Increasing Ho content promotes the formation of long period stacking ordered (LPSO) structure, which changes the mechanical properties of the alloys. As a consequence, the strength of the alloy rises with the increase of Ho addition at room temperature and elevated temperature. However, the elongation of the alloy increases at room temperature but slightly decreases at high temperature when the Ho addition increases. These results are explained from morphology evolution of W-phase and the presence of LPSO phase in different alloys. Highlights • The increasing Ho additions promote the grain refinement of the alloys. • The increasing Ho contents results in the formation of 18R-LPSO structure. • Ho contents change the mechanical property of the alloys at high temperature. [ABSTRACT FROM AUTHOR]

Digital literacy is a crucial skill for accessing the benefits of the digital economy. Analyzing the impact of digital literacy on the risk of falling back into poverty is of great practical significance for achieving sustainable poverty alleviation. Based on data from the China Family Panel Studies (CFPS) in 2018, this paper examines the impact of digital literacy on the risk of returning to poverty for poverty-alleviated households, and investigates its underlying mechanism. The study finds that digital literacy can reduce the risk of returning to poverty by promoting local non-farm employment and migrant work, improving entrepreneurial performance, and expanding entrepreneurial scale. However, digital literacy plays a relatively minor role in reducing the risk of returning to poverty through entrepreneurship compared to employment. In the heterogeneity analysis, this paper concludes that digital literacy is more advantageous for disadvantaged groups. Furthermore, compared to digital entertainment literacy, digital learning literacy is more effective in reducing the risk of returning to poverty. This study has significant implications for understanding and improving the governance mechanism of sustainable poverty alleviation through digital literacy. • Digital literacy can reduce the risk of returning to poverty. • Employment and entrepreneurship are both essential mechanism for reducing the risk of returning to poverty. • Employment plays a more significant role of mechanism than entrepreneurship. • Disadvantaged households benefit more from digital literacy. [ABSTRACT FROM AUTHOR]

In recent years, electrochemical sensors for nucleic acid testing based on CRISPR/Cas12a technology have attracted widespread interest due to their ease of operation and high detection sensitivity. Here, a label-free electrochemical sensor amplified by primer exchange reaction (PER), hybridization chain reaction (HCR) and CRISPR/Cas12a system was developed for analyzing miRNA- 155 and PCB 77. In the presence of targets, PER was initiated, whose products could be used to trigger the trans-cleavage activity of Cas12a for the single-stranded DNA (ssDNA) on the electrode. Afterwards, with the amplification of HCR on the electrode and electrostatic adsorption of Ru(NH 3) 6 3+, the concentration of the targets could be indicated by the DPV intensity with a low background signal. The detection limits for miRNA- 155 and PCB 77 were estimated to be 67 aM and 6.9 pg/L, respectively. This work provides a versatile method for sensitive detection of different targets using the same crRNA and can be used in various biochemical investigations. • A label-free electrochemical sensor was used for the detection of two targets. • PER, CRISPR/Cas system and HCR were applied for signal amplification. • CRISPR/Cas system can decrease the background signal without the usage of PAN. • The same crRNA can be used to detect different targets. [ABSTRACT FROM AUTHOR]

In the continental basins of Northern China (NC), a series of energy resources commonly co-exist in the same basin. As the three typical superimposed basins of different genesis in the NC, the Junggar, Ordos, and Songliao basins were chosen as the research objects. The favorable uranium-bearing structures are generally shown as a basin-margin slope or transition belt of uplifts with the development of faults, which are conducive to a fluid circulation system. The Hercynian, Indosinian, and Yanshanian movements resulted in the development of uranium-rich intrusions which acted as the significant uranium sources. The main hydrocarbon source rocks are developed in the Carboniferous, Permian, Jurassic and Cretaceous. The mature stage of source rocks is concentrated in the Jurassic—Cretaceous, followed by the multi-stage expulsion events. Influenced by the India-Eurasian collision and the subduction of the Pacific Plate, the tectonic transformation in the Late Yanshanian and Himalayan periods significantly influenced the sandstone-type uranium mineralization. The hydrocarbon reservoirs are spatially consistent with sandstone-type uranium deposits, while the hydrocarbon expulsion events occur in sequence with sandstone-type uranium mineralization. In the periphery of the faults or the uplifts, both fluids met and formed uranium concentration. The regional tectonic movements motivate the migration of hydrocarbon fluids and uranium mineralization, especially the Himalayan movement. [ABSTRACT FROM AUTHOR]

A CRISPR-Cas12a controlled chemiluminescence resonance energy transfer (CRET) biosensor was constructed for the detection of cancer biomarker carcinoembryonic antigen (CEA). The CRET probe, a single-strand DNA (ssDNA) with hemin/G-quadruplex on one end and CdSe/ZnS quantum dots (QDs) nanosphere on the other end, was used as the substrate for the trans-cleavage of CRISPR/Cas12a system. The hemin/G-quadruplexes catalyzed the oxidation of luminol in the presence of H 2 O 2. The generating chemiluminescence could excite the CdSe/ZnS QDs encapsulated in the nanosphere, producing CRET. When target CEA specifically identified dual aptamers on the surface of magnetic beads (MBs), the terminal sequence of Aptamer 2 triggered the hybridization chain reaction (HCR), whose product initiated the trans-cleavage activity of CRISPR/Cas12a and destroyed the CRET system. As a result, the luminescence of QDs nanosphere was declined. With HCR, CRISPR-Cas12a trans-cleavage, and mimic DNAzyme catalytic amplification, the biosensor gave a detection limit down to 5.6 pg/mL. Due to the application of CRISPR/Cas12a, the CRET sensor with the characteristics of easy operation and no external light source required was more suitable for point-of-care testing (POCT) detection of various targets. [Display omitted] • A CRISPR-Cas12a controlled CRET sensor was developed for CEA detection. • The CRET probe was constructed by linking hemin/G-quadruplex with CdSe/ZnS QDs nanosphere. • Dual aptamers recognition can enhance the specificity of developed sensor. • HCR and CRISPR-Cas12a system were used to amplify the detection signals. [ABSTRACT FROM AUTHOR]

A novel multifunctional nanoprobe was designed for cancer cell targeted multilayer imaging of two cancer biomarkers. Based on the proposed method, in situ imaging of membrane MUC1 mucin and cytoplasmic microRNA miR-21 coupled with precise photodynamic therapy was achieved. [ABSTRACT FROM AUTHOR]

• A series of solvent additives 1,8-diiodooctane (DIO), 1-chloronaphthalene (CN), 1-phenylnaphthalene (PN), 1-methylnaphthalene (MN) were used to effectively control the morphology and transport properties of a kind of pristine perylene diimide dimer (Bis-PDI-T-EG) films. • The PCE of PerSCs based on the 1-methylnaphthalene doped Bis-PDI-T-EG electron transport layer increase by 18% compared to the reference device without solvent additives. It could be further improved by adding 0.05 wt% graphene together with 0.05 v/v% 1-methylnaphthalene, and the hysteresis effect was reduced. Perylene diimide derivatives (PDIs) are a kind of very promising non-fullerene electron transport material for organic-inorganic perovskite solar cells (PerSCs), owing to their excellent photoelectric properties and low-cost synthesis. However, their tendency to form aggregates strongly influences the film morphology and transport properties. Herein, we provided a simple way to tune the morphology and transport properties of PDIs by solvent additive engineering. A series of solvent additives (1,8-diiodooctane, 1-chloronaphthalene, 1-phenylnaphthalene, 1-methylnaphthalene) was investigated for their role in the morphology and transport property of PDI dimer (Bis-PDI-T-EG) film as well as on the photovoltaic performance of PerSCs. Among these four solvent additives, 1-methylnaphthalene (MN) was found one of the best additive that possesses good adjusting ability to control both morphological and electrical properties of Bis-PDI-T-EG film. The fabricated PerSCs with optimized Bis-PDI-T-EG + 0.05 v/v% MN electron transport layer (ETL) displayed the best power conversion efficiency (PCE) of 14.96%. The performance of PerSCs was further improved by adding 0.05 wt% graphene together with 0.05 v/v% MN, and the maximum PCE of 15.11% was achieved. [ABSTRACT FROM AUTHOR]

Background: Nickel is an occupational and environmental toxicant associated with a number of diseases in humans including pulmonary fibrosis, bronchitis and lung and nasal cancers. Our earlier studies showed that the nickel-exposure-induced genome-wide transcriptional changes, which persist even after the termination of exposure may underlie nickel pathogenesis. However, the mechanisms that drive nickel-induced persistent changes to the transcriptome remain elusive. Results: To elucidate the mechanisms that underlie nickel-induced long-term transcriptional changes, in this study, we examined the transcriptome and the epigenome of human lung epithelial cells during nickel exposure and after the termination of exposure. We identified two categories of persistently differentially expressed genes: (i) the genes that were differentially expressed during nickel exposure; and (ii) the genes that were differentially expressed only after the termination of exposure. Interestingly, > 85% of the nickel-induced gene expression changes occurred only after the termination of exposure. We also found extensive genome-wide alterations to the activating histone modification, H3K4me3, after the termination of nickel exposure, which coincided with the post-exposure gene expression changes. In addition, we found significant post-exposure alterations to the repressive histone modification, H3K27me3. Conclusion: Our results suggest that while modest first wave of transcriptional changes occurred during nickel exposure, extensive transcriptional changes occurred during a second wave of transcription for which removal of nickel ions was essential. By uncovering a new category of transcriptional and epigenetic changes, which occur only after the termination of exposure, this study provides a novel understanding of the long-term deleterious consequences of nickel exposure on human health. [ABSTRACT FROM AUTHOR]

A novel method of catalytic hairpin assembly (CHA) induced dual signal enhancement is developed for rapid detection of miRNA based on fluorescence light-up silver nanocluster (Ag NC). By the hybridization of a hairpin DNA and a single-stranded DNA, a unique probe is firstly designed. In the terminals of this probe, DNA-Ag NCs can be formed and display very weak fluorescence. In the presence of the target miRNA, the reaction of CHA can be triggered, forming two kinds of double-stranded complexes, in which the terminal DNA-Ag NCs are in close proximity to G-rich overhangs and the fluorescent signal can be dramatically enhanced. Compared with many other enzyme-based amplification strategies, this one exhibits distinct advantages of simplicity in experimental operation and a rapid detection process (within 1 h). Moreover, this assay exhibits an excellent selectivity and is successfully applied in the detection of miRNAs in complex biological media, which confirms the reliability and practicality of this protocol. A novel method of catalytic hairpin assembly (CHA) induced dual signal enhancement is developed, which has been used for rapid detection of miRNA based on fluorescence light-up silver nanocluster. Image 1 • A novel method of catalytic hairpin assembly induced dual signal enhancement is developed. • The method is used for miRNA detection based on fluorescence light-up silver nanocluster. • This assay has the advantages of simplicity in experimental operation and a rapid detection process. [ABSTRACT FROM AUTHOR]

In this study, we developed a colorimetric ATP assay based on the ATP-induced aggregation of Au nanoparticles (AuNPs). This aggregation modified the local surface plasmon resonance (LSPR) of the AuNPs, which was used to detect and localize ATP in cells via dark-field imaging. The AuNP aggregation process involved the reaction of two types of functionalized AuNPs with each other: tetrazine-modified AuNPs (Au3-N4) and asymmetrically functionalized trans-cyclooctene-modified AuNPs (Au1-(E)-cyclooctene). This cycloaddition reaction occurs without the need for a catalyst such as the Cu ions that are used in the "click" reactions often employed in assays of this type. Initially, we asymmetrically functionalized both types of AuNPs and let them dimerize, which permitted us to explore the resulting wavelength shift in the LSPR of the AuNPs. Then, to facilitate the specific recognition of ATP, a designed DNA (DNA1) containing an ATP aptamer sequence was attached to carboxyl polystyrene microbeads (MBs). After attaching a different DNA (DNA2, which hybridizes with DNA1) to Au1-(E)-cyclooctene, the assay probe MB/DNA1/DNA2/Au1-(E)-cyclooctene (MB/Au1) was generated. While bound to MB/DNA1, the DNA2/Au1-(E)-cyclooctene cannot react with Au3-N4 due to steric hindrance from the MB. However, in the presence of ATP, the probe MB/Au1 dissociates, and the resulting free DNA2/Au1-(E)-cyclooctene can then react with the Au3-N4, leading to the formation of AuNP aggregates. Dark-field microscopy (DFM) images showed that the LSPR of the AuNPs shifted from the green region (AuNP monomers) to the orange-red region (AuNP aggregates) in the presence of intracellular ATP. Moreover, the AuNP aggregates were found to exhibit significant photothermal effects under 808-nm laser irradiation. Upon introducing the probe MB/Au1 and Au3-N4 into HeLa cells in vitro and in vivo, and then irradiating the cells with a 808-nm NIR laser, the resulting AuNP aggregates showed promising photothermal cancer therapy performance. This assay therefore has the potential to be widely used for the identification and determination of nanoparticles in biological DFM and in tumor theranostics. [ABSTRACT FROM AUTHOR]

A novel aggregation-induced emission (AIE) probe comprised of a hydrophilic protein kinase specific peptide and a hydrophobic tetraphenylethene (TPE) unit was synthesized through click reaction. The prepared TPE-peptide probe could be completely degraded by carboxypeptidase Y (CPY) to release hydrophobic TPE part, which aggregated in buffer solution and showed strong TPE emission. In the presence of casein kinase (CKII), the phosphorylation of peptide prevented the complete degradation by CPY producing the nonemissive probe. Thus, the developed probe can be used to detect CKII homogeneously and conveniently. This detection process can be finished within 1.5 h with high sensitivity (0.05 mU/μL) and good selectivity. The developed method can also be used to screen protein kinase inhibitor even in a complex biological system. Image 1 • A novel AIE probe was synthesized through click reaction. • This probe can be used to detect CKII homogeneously within 1.5 h. • This method can be used to screen protein kinase inhibitor even in a complex biological system. [ABSTRACT FROM AUTHOR]

Abstract A sensitive surface-enhanced Raman scattering (SERS) approach has been developed for detection of microRNA (miRNA) based on target-triggered dual signal amplification including strand displancement amplification (SDA) and hybridization chain reaction (HCR). With the assistant of polymerase and nicking endonuclease (NEase), target miRNA combines with the single stranded template DNA to generate a great amount of trigger DNA which can induce HCR. Coupled the dual cycle amplification of SDA and HCR with the dual enhancement of gold nanoparticles (AuNPs), a low detection limit of 0.5 fM for miRNA is obtained using the proposed strategy. With high sensitivity, universality, rapid analysis, and high selectivity, this method has a great potential for detecting biomolecules with trace amounts in bioanalysis and clinical biomedicine. Highlights • A novel method of dual cycle amplification and dual signal enhancement assisted SERS detection for miRNA is developed. • This method allows the transduction of miRNA detection into DNA-based signal amplification. • This assay has the advantages of wide dynamic range, high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]