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Water can trigger freeze–thaw cycles, acid rain corrosion, and microbial colonisation, all of which destroy stone. Water is one of the most influential factors in the destruction of outdoor stone heritage. Therefore, materials with excellent hydrophobic properties and durability are urgently required to effectively retard long-term stone weathering. In this study, two nanoparticles, TiO2 and SiO2, were used to modify dodecyltrimethoxysilane (DTMS), a waterproof coating commonly used for stone heritage protection, to fabricate nanocomposite superhydrophobic coatings. The micromorphology, water repellence (water contact angle and capillary water absorption), suitability to protect stone heritage (color change and water vapor permeability), and durability (thermal, light, and chemical stability) of DTMS and nanocomposite coatings were evaluated. The scanning electron microscope (SEM) images revealed that adding 0.5% (w/w) SiO2 produced nanoscale roughness on the sandstone surface, leading to superhydrophobicity. The results of ultraviolet -visible (UV–Vis) spectrophotometer showed that adding 0.01% TiO2 shielded more than 90% of UV light but accelerated the decrease in the contact angle under UVA irradiation. The addition of SiO2 was able to avoid the detrimental effect of TiO2 under UV light. The thermogravimetric analysis (TGA) results showed that both SiO2 and TiO2 nanoparticles improved the thermal stability of the coatings. In particular, the fabricated nanocomposite coating, SiO2 and TiO2 co-modified DTMS, had excellent water repellence, low color change and outstanding durability, and retained about 85% of the water vapor permeability of the stone, showing promise for stone protection. [ABSTRACT FROM AUTHOR]

We aimed to construct a method involving the photocatalytic oxidative dehydrogenation of formic acid (FA) to promote the acetone reductive hydrogenation of C–C coupling, where photo-electrons and photo-holes could be effectively used. The results showed that the conversion rates of acetone and FA in the g-C3N4 photocatalytic acetone–FA coupling reaction system were 88.74% and 60.82%, respectively. Further research showed that the Na+ concentration on the surface of the C3N4 photocatalyst was also positively correlated with pinacol selectivity. The g-C3N4 treated with 5 M NaOH showed a high pinacol selectivity of 60.87%, which was increased by 32.30%. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third leading cause of cancer-associated mortality worldwide. Ginsenoside Rh1 (Rh1) is a traditional medicine monomer with antitumor activity; however, the effects of Rh1 in CRC remain to be determined. In the present study, SW620 cells were treated with different concentrations of Rh1. Cell Counting Kit-8, wound healing and Transwell assays were performed to measure cell viability and proliferation, migration and invasion, respectively. Subsequently, the mRNA expression levels of matrix metallopeptidase (MMP)1, MMP3 and tissue inhibitor of metalloproteinases 3 (TIMP3) were detected by reverse transcription-quantitative PCR analysis. In addition, the protein expression levels of MMP1, MMP3, TIMP3, and total or phosphorylated (p-)ERK1/2, P38, JNK were detected by western blotting. Furthermore, tumor growth was examined in a nude mouse xenograft model. The results of the present study indicated that Rh1 was not toxic to CRC cells at various concentrations (0, 50 or 100 µM) and treatment durations (24 or 48 h). However, cell proliferation was suppressed by Rh1 in a dose-dependent manner. Rh1 (100 µM) significantly inhibited cell migration and invasion in vitro. Additionally, Rh1 suppressed the mRNA and protein expression of MMP1 and MMP3, and promoted TIMP3 expression. Rh1 decreased the ratios of p-P38/P38, p-ERK1/2/ERK1-2 and p-JNK/JNK in vitro and in vivo, which suggested that Rh1 inactivated the mitogen-activated protein kinase (MAPK) signaling pathway. Notably, Rh1 markedly decreased tumor volume and weight in vivo. In conclusion, the present study demonstrated that Rh1 inhibited the proliferation, migration and invasion of CRC cells in vitro and tumor growth in vivo. This inhibition was at least partially due to the inhibition of MMP1 and MMP3 expression, the increase in TIMP3 expression level and the MAPK signaling pathway inactivation. Therefore, Rh1 may effectively inhibit the development of CRC as an anticancer drug, and may have a supporting effect during CRC treatment. [ABSTRACT FROM AUTHOR]

One of the major obstacles to improving solar thermal cooling technologies is the high operating temperature requirements of most solar thermal cooling systems. This paper reviews recent advances that could reduce the required heat source temperatures for solar desiccant cooling to the range of 50°C–60°C. These approaches include (i) isothermal dehumidification (e.g. two-stage dehumidification or internal cooled dehumidification) and (ii) pre-cooling of the entry air with ambient heat sinks (e.g. indirect evaporative cooling or geothermal exchange). These techniques can potentially leads to a more thermodynamically efficient solution for utilising recovered heat from flat plate photovoltaic thermal (PV/T) collectors for desiccant regeneration. Analysis of the literature shows that obtainable outlet fluid temperatures from existing PV/T systems nearly match the low temperature desiccant cooling and dehumidification applications. Design and operation factors for achieving sufficiently high outlet fluid temperature in flat plate PV/T collectors include (i) maintaining low mass flow rate per collector area, (ii) addition of a glazed cover and (iii) hydraulic channel diameter optimisation. These factors are reviewed and case studies of complete solar PV/T desiccant cooling are examined. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) provide a new opportunity to produce sustainable energy from the treatment of the organic matter in wastewater. However, the power density of MFCs for large-scale application is limited by the performance of anode, with one of the major factors being low bacterial adhesion capacity. In this work, a novel macroporous sugarcane carbon (SC) is prepared by a direct carbonization process, and is used as anode material in a packed MFC. A maximum power density of 59.94±2.81 W m−3 is achieved in an MFC equipped with the SC anode, which is 2.62 times higher than that of the granular activated carbon (GAC) anode. A microbial analysis shows that the SC anode has a higher amount of biomass and the abundance of Geobacter is 6.6 times higher than that of the GAC anode, which indicates that the SC anode has higher biocompatibility. Further studies show that the macroporous structure, high surface roughness, large surface hydrophobicity and low absolute value of zeta potential favor bacterial adhesion to the SC anode surface. Therefore, this study provides an excellent anode material for high-performance MFCs, and reveals the impact of physicochemical properties on power generation. [ABSTRACT FROM AUTHOR]

A waste paper sludge-derived heterogeneous catalyst (WPS-Fe-350) was synthesized via a facile method and successfully applied for the degradation of Orange II in the presence of oxalic acid under the illumination of ultraviolet light emitting diode (UV-LED) Powder X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electronic microscopy and N 2 sorption isotherm analysis indicated the formation of α-Fe 2 O 3 in the mesoporous nanocomposite. The degradation test showed that WPS-Fe-350 exhibited rapid Orange II (OII) degradation and mineralization in the presence of oxalic acid under the illumination of UV-LED. The effects of pH, oxalic acid concentration and dosage of the catalyst on the degradation of OII were evaluated, respectively. Under the optimal conditions (1 g/L catalyst dosage, 2 mmol/L oxalic acid and pH 3.0), the degradation percentage for a solution containing 30 mg/L OII reached 83.4% under illumination by UV-LED for 80 min. Moreover, five cyclic tests for OII degradation suggested that WPS-Fe-350 exhibited excellent stability of catalytic activity. Hence, this study provides an alternative environmentally friendly way to reuse waste paper sludge and an effective and economically viable method for degradation of azo dyes and other refractory organic pollutants in water. [ABSTRACT FROM AUTHOR]

In the big data era, data are envisioned as critical resources with various values, e.g., business intelligence, management efficiency, and financial evaluations. Data sharing is always mandatory for value exchanges and profit promotion. Currently, certain big data markets have been created for facilitating data dissemination and coordinating data transaction, but we have to assume that such centralized management of data sharing must be trustworthy for data privacy and sharing fairness, which very likely imposes limitations such as joining admission, sharing efficiency, and extra costly commissions. To avoid these weaknesses, in this paper, we propose a blockchain-based fair data exchange scheme, called FaDe. FaDe can enable de-centralized data sharing in an autonomous manner, especially guaranteeing trade fairness, sharing efficiency, data privacy, and exchanging automation. A fairness protocol based on bit commitment is proposed. An algorithm based on blockchain script architecture for a smart contract, e.g., by a bitcoin virtual machine, is also proposed and implemented. Extensive analysis justifies that the proposed scheme can guarantee data exchanging without a trusted third party fairly, efficiently, and automatically. [ABSTRACT FROM AUTHOR]

When large images are used for big data analysis, they impose new challenges in protecting image privacy. For example, a geographic image may consist of several sensitive areas or layers. When it is uploaded into servers, the image will be accessed by diverse subjects. Traditional access control methods regulate access privileges to a single image, and their access control strategies are stored in servers, which imposes two shortcomings: (1) fine-grained access control is not guaranteed for areas/layers in a single image that need to maintain secret for different roles; and (2) access control policies that are stored in servers suffers from multiple attacks (e.g., transferring attacks). In this paper, we propose a novel watermark-based access control model in which access control policies are associated with objects being accessed (called an in-situ model). The proposed model integrates access control policies as watermarks within images, without relying on the availability of servers or connecting networks. The access control for images is still maintained even though images are redistributed again to further subjects. Therefore, access control policies can be delivered together with the big data of images. Moreover, we propose a hierarchical key-role-area model for fine-grained encryption, especially for large size images such as geographic maps. The extensive analysis justifies the security and performance of the proposed model. [ABSTRACT FROM AUTHOR]

• A fungus Simplicillium aogashimaense was discovery on artifacts for the first time. • The biological and physical destruction of the fungus caused fading of the pigments. • Simplicillium aogashimaense had the capacity of copper adsorption. • The morphology of the fungus mycelium was changed on copper-based pigments. Severe fading of the blue (azurite) and green (malachite) pigments occurred on the polychrome pottery figurines excavated from the Duan family cemetery M194 of the Tang Dynasty, in Xianyang, China, and microorganisms were suspected to be involved in this discoloration phenomenon. Therefore, molecular methods were used to identify the dominant strains isolated from azurite and malachite on the pottery figurines. On this basis, the fading mechanism of azurite and malachite from microorganisms was explored. The dominant strain was identified as Simplicillium aogashimaense , and this species has until now, not yet been encountered on cultural heritage objects. It can colonize the polychrome layers of azurite and malachite, causing the deepening of color and the thickening of mycelium after the absorption of Cu(II), resulting in the destruction of the polychrome layers. This study lays a theoretical foundation for the fading of azurite and malachite in polychrome artifacts, providing a scientific basis for their conservation. [Display omitted] [ABSTRACT FROM AUTHOR]

• Platinum exhibited high efficiency hydrogen generation rate of 8.01 mmol h−1. • The photoactive acetonyl-platinum complexes are generated reproducibly. • It is water rather than isopropanol contributing to the hydrogen evolution. The current artificial photocatalysts often suffer from photocorrosion-induced irreversible damage and low efficiency. Here we report that under the UV irradiation of aqueous isopropanol solution, which photolysis to produce acetone and consume photoelectron in time and be oxidized to form acetone. And then the platinum nanoparticles can coordinate with product acetone on their surfaces to create a unique photocatalysis system for high efficient hydrogen evolution. In this system, the inherent close bonding between photoactive surface complexes and metallic platinum sites creates an efficient donor-acceptor system for charge transfer and leads to high efficiency, with hydrogen generation rate of 8.01 mmol⋅ h−1. Furthermore, in the presence of isopropanol the photoactive acetonyl-platinum complexes are generated reproducibly via a continuous isopropanol-to-acetone conversion and thus work sustainably. This finding indicates the possibility of artificially creating self-reproducible systems to drive photocatalytic reactions efficiently and robustly. [ABSTRACT FROM AUTHOR]

Objectives: To observe the clinical effect of the modified painless blistering moxibustion with wheat-grain sized moxa cone on cough variant asthma (CVA) differentiated as pathogenic wind attacking the lung and explore the influences on eosinophil count (EOS) in the peripheral blood and the content of interleukin-4 (IL-4) and tumor necrosis factor-α (TNF-α) in the serum of patients., Methods: Ninety-two patients with CVA of pathogenic wind attacking the lung were randomly divided into an observation group and a control group, 46 cases in each group. In the observation group, the modified painless blistering moxibustion with wheat-grain sized moxa cone was applied to the unilateral Feishu (BL 13), Gaohuang (BL 43) and Zusanli (ST 36) in each session of treatment, once every 3 days. In the control group, budesonide and formoterol powder inhaler was delivered, 4.5 μg per inhalation, once every half an hour after breakfast and dinner; one more time of inhalation needed if the symptoms were not well controlled, but less than 6 times of inhalation per day. The duration of treatment was 8 weeks in both groups. Separately, before and after treatment, and during the 1-month follow-up after treatment completion, the score of the symptoms of traditional Chinese medicine (TCM) was observed in the two groups; using the lung function detector, the indexes of pulmonary function (forced expiratory volume in one second [FEV1], FEV1/forced vital capacity [FVC] and peak expiratory flow [PEF]) were determined, and the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum were determined before and after treatment; and the clinical effect was compared between the two groups., Results: After treatment and in follow-up, the TCM symptom scores were decreased compared with those before treatment in the two groups ( P <0.05), and the score in the observation group was lower than that of the control group in follow-up ( P <0.05). After treatment, FEV1, FEV1/FVC and PEF were increased when compared with those before treatment in the two groups ( P <0.05), and the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum were reduced ( P <0.05); there was no statistical difference in these indexes between the two groups ( P >0.05). After treatment, the total effective rate of the observation group was 95.7% (44/46), which was not different statistically in comparison with the control group (93.5% [43/46], P >0.05). In the follow-up, the total effective rate of the observation group was 95.7% (44/46), which was higher than that of the control group (78.3% [36/46], P <0.05)., Conclusions: The modified painless blistering moxibustion with wheat-grain sized moxa cone may ameliorate the symptoms of CVA of pathogenic wind attacking the lung and improve the pulmonary functions, which is probably related to the regulation of the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum, thereby, reducing the inflammatory response.

Purpose: Xanthohumol is a prenylated flavonoid of plant origin and has been reported to exhibit a spectrum of pharmacological properties including anticancer effects. However, the anticancer properties of Xanthohumol have not been thoroughly evaluated against drug-resistant colon cancer cells. This study was undertaken to evaluate the anticancer effects of Xanthohumol against the human colon cancer cell line HT-29 and normal CDD-18Co cell line., Methods: HT-29 cell viability was evaluated by cell counting kit-8 (CCK8) assay. Apoptotic effects were examined by fluorescence microscopy using DAPI staining and flow cytometry using annexin V/propidium iodide (PI) staining. Effects on cell cycle were studied by flow cytometry while western blot analysis was done to study effects on protein expressions., Results: The results showed that Xanthohumol causes a dramatic decrease in the HT-29 cell viability with an IC50 of 10 µM. However, an IC50 >100 µM for Xanthohumol against the normal CDD-18Co cells suggested cancer cell specific activity. DAPI staining revealed nuclear fragmentation, suggesting xanthohumol induces apoptosis in HT-29 cells. Xanthohumol also caused activation of caspase-3 and 9 and increased the Bax/Bcl-2 ratio. Cell cycle analysis showed that this molecule caused arrest of the HT-29 cells at the G2/M phase of the cell cycle. The induction of G2/M cell cycle was also accompanied with depletion of the expression of cyclin B1. The effects of Xanthohumol were also investigated on the Ras/MEK/ERK signalling pathway which revealed that Xanthohumol also blocks the MEK/ERK signalling pathway in colon cancer cells in a concentration-dependent manner., Conclusions: Xanthohumol may prove an efficient lead molecule for the development of more potent anticancer agents through semi-synthetic approaches.

We demonstrate the compression of noise-like pulses in an Yb-doped fiber master-oscillator power-amplifier (MOPA). The seed source of the MOPA is an NPR mode locked fiber laser delivering 5.94-ps dissipative soliton pulses with a repetition rate of 37.48 MHz. After amplification in the Yb-doped fiber amplifier, stable noise-like pulses with maximum power of 5 W are obtained. Subsequently a grating pair is used to tailor the spectrum and compensate the dispersion of the amplified noise-like pulses. The pedestal of de-convolution autocorrelation trace is compressed from 6.5 ps to 920 fs. To the best of our knowledge, this is the first time that the pedestal of a noise-like pulse is compressed to femtosecond region.

The heterochronic gene let-7 serves as a tumor suppressor microRNA by targeting various oncogenic pathways in cancer cells. Considerable evidence indicates that reduced expression of let-7 might be associated with poor clinical outcome in patients with cancer. Here, we report that the expression levels of three let-7 family members, let-7a, let-7b, and let-7g, were significantly decreased in the patients with breast cancer with lymph node metastasis compared with those without lymph node metastasis. Enforced expression of let-7b significantly inhibits breast cancer cell motility and affects actin dynamics. Using bioinformatic and experimental approaches, four genes in the actin cytoskeleton pathway, including PAK1, DIAPH2, RDX, and ITGB8, were identified as let-7 direct targets. Blocking the expression of PAK1, DIAPH2, and RDX significantly inhibits breast cancer cell migration induced by let-7b repression. Our results indicate that reconstitution of let-7 expression in tumor cells could provide a novel therapeutic strategy for the treatment of metastatic disease.

The RNA-binding protein LIN28A regulates the translation and stability of a large number of mRNAs as well as the biogenesis of certain miRNAs in embryonic stem cells and developing tissues. Increasing evidence indicates that LIN28A functions as an oncogene promoting cancer cell growth. However, little is known about its molecular mechanism of cell cycle regulation in cancer. Using tissue microarrays, we found that strong LIN28A expression was reactivated in about 10% (7.1-17.1%) of epithelial tumors (six tumor types, n = 369). Both in vitro and in vivo experiments demonstrate that LIN28A promotes cell cycle progression in cancer cells. Genome-wide RNA-IP-chip experiments indicate that LIN28A binds to thousands of mRNAs, including a large group of cell cycle regulatory mRNAs in cancer and embryonic stem cells. Furthermore, the ability of LIN28A to stimulate translation of LIN28A-binding mRNAs, such as CDK2, was validated in vitro and in vivo. Finally, using a combined gene expression microarray and bioinformatics approach, we found that LIN28A also regulates CCND1 and CDC25A expression and that this is mediated by inhibiting the biogenesis of let-7 miRNA. Taken together, these results demonstrate that LIN28A is reactivated in about 10% of epithelial tumors and promotes cell cycle progression by regulation of both mRNA translation (let-7-independent) and miRNA biogenesis (let-7-dependent).

The replacement of used-up ink cartridges is unavoidable, but it makes the existing characterization model far from accurate, while recharacterization is labor intensive. In this study, we propose a new correction method for cellular Yule-Nielsen spectral Neugebauer (CYNSN) models based on principal component analysis (PCA). First, a small set of correction samples are predicted, printed using new ink cartridges, and then measured. Second, the link between the predicted and measured reflectance weights, generated by PCA, is determined. The experimental results show that the proposed method provides a significant and robust improvement, since not only the color change between original and new inks but also the systemic error of CYNSN modelsis taken into account in the method., (© 2011 Optical Society of America)