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• Amino-terminated graphitic CDs was engineered for Golgi apparatus targeting. • This CDs were successfully applied for monitoring dynamic changes of the Golgi morphology. • Local polarity changes in Golgi apparatus can be tracked with CDs. Cellular polarity plays a crucial role in numerous pathological and biological processes. For example, the polarity of the Golgi apparatus strongly influences the intracellular protein processing and transport. The development of fluorescent probes for tracking of subcellular levels of polarity changes remains a great challenge. Herein, amino-terminated carbon dots (CDs) which have superior Golgi apparatus targeting ability and polarity-sensitive property were designed and fabricated by the mixing of p-phenylenediamine and ethylenediamine through a simple solvothermal route. CDs allowed effectively imaging of Golgi apparatus morphological dynamics during cell division and cell death, while folic acid-conjugated CDs possessed high folate-receptor binding affinity and could be used to identify cancer cells. Importantly, the Golgi polarity in apoptotic cells was found to be higher than that of non-apoptotic cells. This work provided a reliable and robust way to real-time track the changes of Golgi apparatus and the local polarity variation, implying the great potential of CDs for the apoptosis evaluation and therapeutic drug screening. [ABSTRACT FROM AUTHOR]

Sodium Zirconium Phosphate (NaZr 2 (PO 4) 3 , hereinafter NZP) and monazite are both potential materials for immobilization of nuclear waste. In this work, novel (1- x)Sr 0.5 Zr 2 (PO 4) 3 - x NdPO 4 composite ceramics (x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0) for simultaneously immobilizing the simulated fission product (FP) Sr and trivalent minor actinide (MA) Nd were prepared by one-step microwave sintering technique, in which Sr and Nd were immobilized into NZP and monazite type structures, respectively. The phase evolution and microstructure of the samples were investigated by X-ray diffraction (XRD), Raman, and backscattering scanning electron microscopy (BSE). The results showed that the expected composite ceramics were successfully obtained by one-step microwave sintering at 1050 °C for 2 h. The as-prepared samples consisted of Sr 0.5 Zr 2 (PO 4) 3 and NdPO 4 phases, and the content of the two phases varied regularly as x changed, generally conforming to the designed nominal chemical composition. Importantly, the composite ceramics presented the homogenous and dense microstructure. The relative density of the composite ceramics was more than 95%, meanwhile, the Vickers-hardness of the samples was higher than 600 MPa. It was indicated that NZP-monazite type composite ceramics could be a potential matrix for the simultaneous immobilization of actinide and fission product. [ABSTRACT FROM AUTHOR]

As the capital economic circle, Jing-Jin-Ji faces a serious shortage of land resource and a deterioration of the ecological environment owing to economic development. Alleviating ecological pressure has become a focus issue in the region. Extant studies have mainly focused on the ecological carrying capacity of individual regions, while it is lacking for the research on the ecological dependency relationship between the various regions. In this article, the authors analyze the ecological footprint transfer between Jing-Jin-Ji and China's other provinces by using multi-regional input–output method. According to the results, the metal/non-metallic mineral and agriculture industries in Jing-Jin-Ji exported a large amount of ecological footprint to the eastern coastal areas. However, the ecological footprint outflow of Jing-Jin-Ji can be attributed to Hebei province, with Beijing and Tianjin showing some net inflow. In interior Jing-Jin-Ji, Hebei has transferred large ecological footprint to Beijing and Tianjin, but Hebei has not achieved the equivalent economic benefits. Thus, Jing-Jin-Ji should further increase its dependence on ecological resources in other provinces; Hebei should especially reduce metal and agriculture product exports. Meanwhile, an ecological compensation system should be established to use the funds provided by Beijing and Tianjin to support the transformation of economic growth mode in Hebei. [ABSTRACT FROM AUTHOR]

Objective: To investigate the levels of NLRC5 and autophagy in women with leiomyoma and endometriosis and the correlation between NLRC5 level and autophagy level.Design: Case-control study.Setting: Clinics.Patient(s): Sixty-five patients were recruited: 30 women with endometriosis were compared with 35 women with leiomyoma.Intervention(s): Endometriosis was definitively diagnosed during surgery by laparoscopy or laparotomy and was confirmed by histopathological evaluation (n=30). Secretory phase ectopic endometrium tissues and eutopic endometrium tissues were obtained from 30 women with endometriosis. Control endometrium tissues were collected at hysterectomy from 35 women with leiomyoma. Immunohistochemical staining of NLRC5, LC3, Beclin1 and P62 were performed.Main Outcome Measure(s): A semiquantitative analysis was performed. Correlations between NLRC5 level and LC3, Beclin1, P62 levels were compared.Result(s): The expressions of NLRC5 and P62 in the ectopic and eutopic endometrium of endometriosis groups were significantly higher than that in the endometrium of leiomyoma group. And their expressions in ectopic endometrium were significantly up-regulated compared to the eutopic endometrium. The expressions of LC3 and Beclin1 were down-regulated in the ectopic and eutopic endometrium of endometriosis groups compared to the leiomyoma group. LC3 and Beclin1 levels were lower in ectopic endometrium than in the eutopic endometrium. There is a negative correlation between NLRC5 level and LC3, Beclin1 levels. There is a positive correlation between NLRC5 level and P62 level.Conclusion(s): There is a negative correlation between NLRC5 level and autophagy level. NLRC5 and autophagy combined may as promising predictors in patients with endometriosis. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is one of the most common tumors, so far, there still aren’t good therapeutic methods. Looking for new targets makes a top priority. In this study, we found a OCT4 pseudogene, POU5F1B was significantly upregulated in HCC cells and tissues, patients with high POU5F1B had shorter survival time compared to patients with low POU5F1B expression. POU5F1B overexpression promoted HCC proliferation, while its knockdown inhibited HCC proliferation determined by MTT assay, soft agar growth assay, BrdU incorporation assay, and cell cycle assay. Mechanism analysis suggested POU5F1B could activate AKT, AKT inhibition in HCC cells with POU5F1B overexpression significantly inhibited cell proliferation compared to cells only with POU5F1B overexpression, suggesting POU5F1B promoted HCC proliferation by activating AKT. Finally, we analyzed the relationship between POU5F1B expression and AKT activity in HCC tissues, and found POU5F1B expression was positive correlated with activated AKT. Taken together, our findings suggested POU5F1B promoted HCC proliferation by activating AKT, and provided a new target for HCC therapy. [ABSTRACT FROM AUTHOR]

The transient receptor potential vanilloid 4 (TRPV4) is a highly Ca 2 + -permeable non-selective cation channel in TRPV family. Accumulating evidence hints that TRPV4 play a significant role in a wide diversity of pathologic changes. Fibrosis is a kind of chronic disease which was characterized by the formation of excessive accumulation of extracellular matrix (ECM) components in tissues and organs. In recent years, a growing body of studies showed that TRPV4 acted as a crucial regulator in the progression of fibrosis including myocardial fibrosis, cystic fibrosis, pulmonary fibrosis, hepatic fibrosis and pancreatic fibrosis, suggesting TRPV4 may be a potential therapeutic vehicle in fibrotic diseases. However, the mechanisms by which TRPV4 regulates fibrosis are still undefined. In this review, firstly, we intend to sum up the collective knowledge of TRPV4. Then we provided the latent mechanism between TRPV4 and fibrosis. We also elaborated the distinct signaling pathways focus on TRPV4 with fibrosis. Finally, we discussed its potential as a novel therapeutic target for fibrosis. [ABSTRACT FROM AUTHOR]

In this work, 0.6Sr 0.5 Zr 2 (PO 4) 3 -0.4Ce 1- x Nd x PO 4 (x = 0–1) multiphase ceramics were fabricated using a one-step microwave sintering technique, where Sr and Ce/Nd were utilized as the substitutes for the fission products 90Sr and actinide nuclides in high-level radionuclide wastes, respectively. The influences of Sr/Ce/Nd co-incorporation on the phase evolution, crystal structure, micromorphology, densification, and chemical stability of the as-prepared multiphase ceramic waste forms were systematically investigated. It was detected that the multiphase ceramics were composed of Sr 0.5 Zr 2 (PO 4) 3 (SrZP) phase and monazite phase regardless of x value, and (Ce, Nd)PO 4 monazite solid solution was formed with Ce/Nd substitution. Rietveld refinement results further verified the cell parameters of (Ce, Nd)PO 4 monazite solid solution regularly decreased with increasing Nd replacement, and the structural change of crystalline monazite did not affect the structure of SrZP phase. All samples presented a well-compacted and homogeneous microstructure, and their micromorphology did not change significantly with the replacement of Ce by Nd. Moreover, the relative density of the as-prepared multiphase ceramics all reached more than approximately 94.5 %, demonstrating excellent densification. Importantly, the good compatibility of SrZP and (Ce, Nd)PO 4 monazite phases brought out superior chemical stability. The normalized elemental leaching rate showed no significant change for different Ce/Nd substituted samples, whose normalized leaching rates of Sr, Ce, and Nd were about 10−4 g/(m2·d), 10−7 g/(m2·d), and 10−6 g/(m2·d) order of magnitude, respectively. It is demonstrated that SrZP-(Ce, Nd)PO 4 multiphase ceramics can be used as candidate materials for simultaneously immobilizing fission products and actinide nuclides of high-level nuclear wastes. [ABSTRACT FROM AUTHOR]

Development of rapid, sensitive, and selective method for pathogenic bacteria detection is of great importance for food safety, medical diagnostic, and environmental monitoring. Currently, most techniques for low numbers of bacteria detection require advanced instrumentation or skilled operators. Herein, we present a facile colorimetric detection platform for bacterial detection using Ag nanoplates as chromogenic substrate, which takes advantages of the high specificity and affinity of aptamer and the ability of catalase to hydrolyze H 2 O 2 that can etch Ag nanoplates. By introducing catalase to the sandwich structure composed by dual-aptamer recognition strategy, bacteria detection signal is converted to the peak shift of LSPR and colorimetric change. This proposed method allows a fast naked-eye detection of S. aureus at the concentration of 60 CFU/mL based on the combination of streptavidin-biotin system and inherent sensitivity of plasmonic Ag nanoplates. Owing to the high selectivity and sensitivity, as well as the low-cost and good adaptability, this plasmonic assay is expected to be suitable for pathogenic bacteria detection in resource-limited settings. Dual aptamer-based plasmonic detection platform for S. aureus was fabricated using silver nanoplates as the signal transducer. [Display omitted] • Silver nanoplates are outstanding chromogenic substrates for the construction of plasmonic assay. • Dual-aptamer recognition strategy can achieve highly sensitive and selective detection of S. aureus. • RGB approach proposed could potentially be adapted for the development of low-cost, portable detection devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • A piezoresistive sensor is prepared by coating MWCNTs on a 3D PET/PE nonwoven. • The combination of PET/PE fibers and thermal coating enhances the coating fastness. • Human body motion can be precisely detected by the sensor. • A sensory network is further assembled to map the spatial pressure distribution. Wearable piezoresistive sensors have attracted increasing attention because of their important applications in wearable electronics, smart textiles and human–machine interaction. However, existing piezoresistive sensors still suffer from problems including expensive starting materials, weak bonding fastness between conductive substances and substrates, limited sensing range and poor comfort. Herein, we report a three-dimensional (3D) piezoresistive sensor based on a nonwoven substrate composed of highly crimped bicomponent fibers. The unique core-sheath structure of these fibers in combination with a thermally-assisted coating method ensures the swift and tight adhesion of multi-walled carbon nanotubes (MWCNTs) on fiber surface, and thus making the nonwoven conductive. With the multi-layered fibrous structure, the resultant sensor exhibits good flexibility, high sensitivity (5.57% and 0.113% kPa−1 in the range of 0–7 and 30–131.32 kPa, respectively), broad dynamic sensing range (0–131.32 kPa), fast response/relaxation (105/156 ms), as well excellent breathability and long-term reliability. Versatility of this sensor is proved by real-time detection of both small and large human motions (such as pulse, speech recognition and joint motion). A sensor network containing 16 sensors is further developed to precisely map and recognize the position, shape and local distribution of pressure. Moreover, the sensor is fabricated by using affordable materials and scalable methods. Taken together, we believe this work may open up a new perspective for the design of high-performance wearable piezoresistive sensors. [ABSTRACT FROM AUTHOR]

Abstract: The effect of Ni addition on the exothermic reaction in the Ti–C–BN system was investigated using differential thermal analysis (DTA). Based on DTA and X-ray diffraction (XRD) analyses, a reaction path for the formation of TiC x N y and TiB2 in the Ni–Ti–C–BN system was proposed in which the reaction initiated with the solid-state diffusion between Ti and BN. The resultant TiN x then reacted with Ni to form Ni–Ti compounds (e.g., Ti2Ni). With increasing temperature, a Ni–Ti–N eutectic liquid phase formed between the Ni–Ti compounds and TiN x at about 1110°C, enabling the dissolution of C and B in the melt to form Ni–Ti–N–C–B liquid. Finally, TiC x N y and TiB2 formed and precipitated out of the liquid. [Copyright &y& Elsevier]

Abstract: An experimental study on direct formation of TiC x N y –TiB2 ceramics by self-propagating high-temperature synthesis (SHS) was conducted using a Ti–B4C–BN system. The effects of the C/(C+N) ratio on the combustion behavior and reaction products were investigated. Experimental characterizations of quenched samples show that the combustion reaction started with the formation of highly substoichiometric TiN y and TiB due to the solid-state reaction between Ti and BN; and then the TiN y precursor and TiB dissolved back into the titanium melt, forming the Ti–B–N liquid, which in turn transformed to the Ti–B–N–C liquid due to the dissolution of the carbon atoms diffused away from B4C. Finally, the TiC x N y and TiB2 particles are formed from the melt through the dissolution-precipitation mechanism. [Copyright &y& Elsevier]

Abstract: In this paper, a simple way of fabricating TiC x N y –TiB2 ceramics through the combustion reaction of Ti, C and BN powder mixtures in an argon atmosphere is reported with an emphasis on the effects of the C/(C+N) ratio on the SHS reaction behaviors and mechanism. With the increase in the C/(C+N) ratio, the combustion temperature shows a zigzag variation behavior; the combustion wave velocity displays a similar variation tendency as did in the combustion temperature while the ignition delay time increases progressively. XRD results confirmed that TiC x N y –TiB2 could form in all the samples. Microstructural observations revealed that both TiC x N y and TiB2 grains had fine sizes of less than 1μm in the products when the C/(C+N) ratio was lower than 0.5. Based on the characterization of quenched samples, the formation mechanism of the titanium carbonitride is proposed. Namely, the formations of TiN0.3 and TiN are followed by the incorporation of C in TiN x to form the titanium carbonitride solid solution. [Copyright &y& Elsevier]

Aggregation-induced electrochemiluminescence (AIECL) technology has aroused widespread interest due to the significant improve in ECL response by solving the problems of aggregation-caused quenching and poor water solubility of the luminophore. However, the existing AIECL emitters still suffer from low ECL efficiency, additional coreactants and complex synthesis steps, which greatly limit their applications. Herein, luminol, as a kind of AIE molecule, was assembled with Zn2+ nodes to obtain a novel microflower-like Zinc-luminol metal-organic gel (Zn-MOG) by one-step method. In the light of the strong affinity of N atoms in luminol ligand to Zn2+, Zn-MOG with vigorous viscosity and stability can be formed immediately after vortex oscillation, overcoming the main difficulties of the complicated synthesis steps and poor film-forming performance encountered in current AIECL materials. Impressively, an AIECL resonance energy transfer (RET) biosensor was constructed using Zn-MOG as a donor and Alexa Fluor 430 as an acceptor in combination with DNA-Fuel-driven target recycling amplification for the ultrasensitive detection of PiRNA-823. The fabricated biosensor exhibited a wide linear relationship in the range of 100 aM to 100 pM and a detection limit as low as 60.0 aM. This work is the first to realize the construction of ECL emitters using the AIE effect of luminol, which provides inspiration for the design of AIECL systems without adding coreactants. [ABSTRACT FROM AUTHOR]

Metal organic gels (MOGs) are a new kind of intelligent soft materials with excellent luminescence properties. However, MOGs with dual electrochemiluminescence (ECL) properties have not been reported. In this study, using Eu3+ as metal node, 4′-(4-carboxyphenyl)-2,2′:6′,2″-terpyridine (Hcptpy) and Luminol as organic ligands, a novel dual-ligand Europium-organic gels (Eu-L-H MOGs) were prepared by simple mixing at room temperature. On the one hand, Eu-L-H MOGs could exhibit strong and stable anodic ECL signals in the phosphate buffered saline (PBS) without the addition of co-reactants, which came from the blue emission of Luminol. On the other hand, using K 2 S 2 O 8 as a cathodic co-reactant, Eu-L-H MOGs produced cathodic signals, which were derived from the red emission of Eu sensitized by Hcptpy through the antenna effect. Based on the independent dual ECL signals of Eu-L-H MOGs, we selected Alexa Flour 430 as the receptor and anodic ECL emission of Eu-L-H MOGs as the donor to construct the ECL resonance energy transfer (ECL-RET) ratio biosensor, which utilized exonuclease III assisted DNA cycle amplification to achieve ultrasensitive detection of the I27L gene. The detection linearity of I27L ranged from 1 fM to 10 nM, with a detection limit as low as 284 aM. This study developed a straightforward technique for obtaining a single luminescent material with dual signals, and further broadened the analytical application of MOGs in the realm of ECL. [ABSTRACT FROM AUTHOR]

The dense NaZr 2 (PO 4) 3 (NZP) ceramics were successfully prepared by a microwave sintering process with x wt.% ZnO as a sintering aid (where x = 0, 0.5, 1.0, 2.0 and 3.0). The effects of ZnO additive on the crystal structure, microstructure and sintering behavior of as-prepared NZP ceramics were systematically investigated. The single NZP phase can be achieved in the wide temperature range of 900–1200 °C holding for 2 h by microwave-sintering technology. The addition of ZnO sintering aid would not noticeably change the crystal structure of NZP. Importantly, ZnO additive significantly promoted the densification and 1.0 wt% ZnO-added sample possessed the maximum relative density of 96.5% after sintering at 1100 °C, considerably higher than that of pure NZP sample. Besides, the Vickers hardness of the above sample could attain near 800 MPa, which is about four times as hard as the pure NZP ceramics without ZnO additive. It was suggested that the combination of microwave sintering with appropriate addition of ZnO sintering aid would provide a convenient and efficient method for rapid fabrication of dense NZP ceramics. [ABSTRACT FROM AUTHOR]

Dynamic DNA nanodevices-based assembly is currently well developed for a broad range of analytical applications. However, some problems persist, such as false positives, nuclease digestions, and exclusive interferences with single signal in complex cellular environment. Herein, we have established a method for imaging cellular miR-155, where it induced assembly of two tetrahedral DNA frameworks (TDFs), TDF-1 and TDF-2, both of which had four fluorescence modified hairpins (Cy3 for TDF-1 and Cy5 for TDF-2, respectively) at each angle, into polymeric tetrahedral DNA frameworks (PTDFs). The formation of PTDFs was greatly dependent on miR-155 overexpressed in breast cancer cells since miR-155 drove catalytic hairpin assembly (CHA) reaction by opening the hairpins at the vertices of TDF-1 to hybridize with TDF-2. Upon the completion of hybridization, the miR-155 was released, starting the next cycle of the CHA reaction. Measurements of atomic force microscopy (AFM) and Förster resonance energy transfer (FRET) showed that the formation of PTDFs occurred owing to the multivalent assembly of TDF-1 and TDF-2. By utilizing the formation of PTDFs, miR-155 was detected in a linear range from 0.5 nM to 30 nM with a 0.35 nM limit of determination, enabling the successful imaging of endogenous miR-155 in live cells through the FRET signal from Cy3 to Cy5. These studies demonstrated that this method significantly strengthened the resistance nuclease to digestion and stable ability with exclusive interference. Our present work has the following three advantages: • A dynamic assembly system that integrated tetrahedral DNA frameworks TDFs with catalytic hairpin assembly reaction was proposed for ratiometric sensing miR-155. • TDFs with higher capacity of hairpins exhibited excellent internalization and nuclease-resistant ability for the enhanced FRET signal, which is favorable for minimizing interferences and keeping stable in biological environment. • Target miR-155 could circularly trigger polyvalence assembly of TDF-1 and TDF-2, which is available for dynamic imaging intracellular miR-155 with higher selectivity and sensitivity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Reaction between lignin model compound and ClO2 is researched by UV–vis. [•] Reaction mechanism of lignin model compound oxidation by ClO2 is derived. [•] Kinetics for lignin model compound oxidation by ClO2 is propose. [•] Bring new door open for resolving the environmental pollution in ECF bleaching. [ABSTRACT FROM AUTHOR]

Abstract: The TiB2–AlN and TiB2–AlN–TiN ceramic matrix composites were successfully produced by self-propagating high-temperature synthesis (SHS) reactions from the Al–Ti–BN compacts through the manipulation of the Al reactant content. The effects of the Al content on the adiabatic and practical maximum combustion temperatures, wave velocity, phase composition and microstructure of the synthesized products, and reaction mechanism were investigated in detail. Thermodynamically and practically, the reaction was most exothermic for the Al content being 35.5wt.% in the reactants to produce only the dual TiB2–AlN phases. Kinetically, the reaction commenced with the formation of Al3Ti, and then proceeded with the interactions of the Al–Ti intermetallics/melts with BN to yield the AlN and TiB2 phases. The substantial reaction between the elemental Ti and BN into formation of TiN took place only in the low Al content samples. On the other hand, the presence of considerable amount of the TiN grains effectively inhibited the abnormal growth of the TiB2 grains, leading to very fine microstructures; whereas, the grain growth of TiB2 and AlN as well as their inhomogeneous distribution was enhanced by the increase in the Al reactant, while TiN was completely inhibited from development. [Copyright &y& Elsevier]