Metal–organic frameworks (MOFs) are promising adsorbents for extraction of uranium(VI) due to their high surface area and abundant active site. However, the smaller pore size (< 2 nm) and harsh ...synthesis conditions (e.g., high temperature and pressure) severely hinder MOFs practical applications in some cases. Herein, we developed a simple and facile method to prepare hierarchically porous Cu-BTC that contained micropores, mesopores and macropores. The as-synthesized hierarchically porous Cu-BTC showed high uptake capacity (406.9 mg g
−1
) and removal efficiency (99.7%) in the capture of uranium(VI) from an aqueous solution. Thermodynamics results indicate the spontaneous nature of uranium(VI) adsorption process onto hierarchically porous Cu-BTC. In addition, Langmuir isotherm and pseudo-second-order models were found to be more suitable in describing the adsorption process of uranium(VI) than those of Freundlich and pseudo-first-order models. These results indicate that hierarchically porous MOFs obtained from rapid room-temperature synthesis are promising adsorbents for the removal of uranium(VI) from aqueous solutions.
Metal organic frameworks (MOFs) are excellent adsorbents that provide abundant specific surface area, adjustable pore structure, and rich active sites. The purpose of this study was to prepare ...composites with hydrophobic and high microporous specific surface area and to adsorb toluene gas in moist ambience. An ethanol activation-assisted hydrothermal method was proposed to synthesize copper-benzene-1,3,5-tricarboxylic acid (Cu-BTC) metal-organic framework, Cu-BTC, and ZSM-5 molecular sieve composites (Cu-BTC@ZSM-5). The dynamic adsorption process of toluene on different adsorbents was investigated, and the results showed that the toluene adsorption capacity of Cu-BTC@ZSM-5 (158.6 mg/g) was 2.53 times higher than Cu-BTC (62.7 mg/g), when the ZSM-5 content is 5% and the humidity is 30%RH. Compared with other factors, the humidity inhibited the adsorption of toluene on Cu-BTC@ZSM-5. Langmuir model and the pseudo-second kinetics model can better describe the adsorption behavior of Cu-BTC@ZSM-5. The thermodynamic results showed the adsorption process was a spontaneous exothermic process at low temperature and mainly physical adsorption. The relative regenerability can still up to 80.4% after six cycles. The adsorption mechanisms of Cu-BTC@ZSM-5 were pore-filling adsorption, π-π interaction, cation-π bonding, and hydrophobic interactions. This study will help to design a systematic route to evaluate the adsorption performance of Cu-BTC@ZSM-5 for toluene.
Biscogniauxia nummularia (Bull.) Kuntze is a fungus which induces strip-cankers on beech, commonly referred to as charcoal canker. The symptoms of infection are visible on the host tree’s bark as ...elongated, blackish bark lesions on the trunk and branches. Recent years have shown that, due to climate change causing local epidemics, the species is increasing its economic impact in Mediterranean regions. Until recently, B. nummularia was considered rare and uncommon in central Europe. However, in the last few years it has been noticed more often, mostly in coniferous trees, which are out of B. nummularia’s host range. A similar situation has been observed with the closely related species Biscogniauxia mediterranea (De Not.) Kuntze, which prior to 2017 had not been observed in central Europe at all. This study shows the genetic diversity of mid-European strains of Biscogniauxia spp. (based on the ITS, TEF1, TUB2 and ACT regions) and, as the first in Europe, presents a molecular investigation of this species isolated from coniferous trees. It is also the first attempt at estimating the potential impact of this pathogenic fungus on European forestry management in the close future.
Clustered protocadherins (PCDHs) map in tandem at human chromosome 5q31 and comprise three multi-genes clusters: α-, β- and γ-PCDH. The expression of this cluster consists of a complex mechanism ...involving DNA hub formation through DNA-CCTC binding factor (CTCF) interaction. Methylation alterations can affect this interaction, leading to transcriptional dysregulation. In cancer, clustered PCDHs undergo a mechanism of long-range epigenetic silencing by hypermethylation.
In this study, we detected frequent methylation alterations at CpG islands associated to these clustered PCDHs in all the solid tumours analysed (colorectal, gastric and biliary tract cancers, pilocytic astrocytoma), but not hematologic neoplasms such as chronic lymphocytic leukemia. Importantly, several altered CpG islands were associated with CTCF binding sites. Interestingly, our analysis revealed a hypomethylation event in pilocytic astrocytoma, suggesting that in neuronal tissue, where PCDHs are highly expressed, these genes become hypomethylated in this type of cancer. On the other hand, in tissues where PCDHs are lowly expressed, these CpG islands are targeted by DNA methylation. In fact, PCDH-associated CpG islands resulted hypermethylated in gastrointestinal tumours.
Our study highlighted a strong alteration of the clustered PCDHs methylation pattern in the analysed solid cancers and suggested these methylation aberrations in the CpG islands associated with PCDH genes as powerful diagnostic biomarkers.
•Bed deactivation in Cu-BTC is higher than in activated carbon.•Cu-BTC is very sensitive to heavier components of natural gas (C3 and C4).•Cu-BTC big cage maximize butane molecules interaction.
We ...tested the MOF framework Cu-BTC for natural gas (NG) storage. Adsorption isotherms of C1–C4 alkanes were simulated applying the Grand Canonical ensemble and the Monte Carlo algorithm in a classical molecular mechanics approach. Experimental monocomponent isotherm of the alkanes was used to validate the force field. We performed multicomponent adsorptions calculations for three different quaternary mixtures of C1–C4 alkanes, matching typical NG streams composition, and predicted theoretical storage capacities, efficiency and accumulation of the NG within that composition. Despite being one of the frameworks with greatest storage capacity of methane, we found that Cu-BTC presented great sensitivity to the variation of the heavier alkanes in NG composition. When we increase the percentage of butane from 0.1% to 0.7% in the mixture, the mass of components retained in the discharge pressure (1bar) increases from 35 to 60%. We also perform siting and interaction energy investigations and compare the NG storage performance of the Cu-BTC with that of activated carbons. To our knowledge, this is the first study regarding the efficiency of the NG storage in Cu-BTC.
Background
Intrahepatic cholangiocarcinoma (ICC) is a subtype of biliary tract cancer (BTC). Recently, downsizing chemotherapy has been applied to initially unresectable BTCs, including ICC.
Case ...presentation
We report a case of liver resection in a 23-year-old woman who was diagnosed with initially unresectable ICC attached to the inferior vena cava, with portal vein (PV) cavernous transformation. Positron emission tomography (PET) showed fluorodeoxyglucose (FDG) uptake in the para-aortic lymph nodes. Upon using downsizing chemotherapy (the combination of gemcitabine GEM and cisplatin CDDP), the size of tumor reduced by 55% and FDG uptake in the para-aortic lymph node metastases disappeared. A right hemihepatectomy was performed, along with dissection of lymph nodes, including the para-aortic lymph nodes. The PV cavernous transformation was preserved to maintain collateral flow as much as possible, as it was considered to originate from a congenital anomaly. Pathological examination revealed that R0 resection was performed and that there were no viable neoplastic cells remaining in the para-aortic lymph nodes. The patient is alive at 31 months after initial treatment, with a local recurrence.
Conclusion
Downsizing chemotherapy with GEM plus CDDP followed by radical surgical resection is an attractive treatment for initially unresectable BTC.
The image-based data hiding method is a technology used to transmit confidential information secretly. Since images (e.g., grayscale images) usually have sufficient redundancy information, they are a ...very suitable medium for hiding data. Absolute Moment Block Truncation Coding (AMBTC) is one of several compression methods and is appropriate for embedding data due to its very low complexity and acceptable distortion. However, since there is not enough redundant data compared to grayscale images, the research to embed data in the compressed image is a very challenging topic. That is the motivation and challenge of this research. Meanwhile, the Hamming codes are used to embed secret bits, as well as a block code that can detect up to two simultaneous bit errors and correct single bit errors. In this paper, we propose an effective data hiding method for two quantization levels of each block of AMBTC using Hamming codes. Bai and Chang introduced a method of applying Hamming (7,4) to two quantization levels; however, the scheme is ineffective, and the image distortion error is relatively large. To solve the problem with the image distortion errors, this paper introduces a way of optimizing codewords and reducing pixel distortion by utilizing Hamming (7,4) and lookup tables. In the experiments, when concealing 150,000 bits in the Lena image, the averages of the Normalized Cross-Correlation (NCC) and Mean-Squared Error (MSE) of our proposed method were 0.9952 and 37.9460, respectively, which were the highest. The sufficient experiments confirmed that the performance of the proposed method is satisfactory in terms of image embedding capacity and quality.
In this study, a newly materials based on copper–benzene-1,3,5-tricarboxylate/polyaniline (PANI/Cu-BTC) composite was investigated for NH3 sensing. Cu-BTC was grown on the PANI a hydrothermal ...process. The sensing performance of as-grown product was studied for different concentrations of NH3 at room temperature. The results reveal that Cu-BTC/PANI composite exhibit high sensitivity toward NH3. The good sensing performance of the composite was attributed to high surface area and good affinity of Cu-BTC for NH3, which can act like preconcentrator for the NH3 gas sensing.
Ternary Z-scheme photocatalysts were constructed using metal-organic frameworks-based AgI/Ag/Cu
3
(BTC)
2
composites via a facile procedure. The morphology, structure, chemical composition, optical ...and photo-electrochemical properties of the photocatalysts were analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis diffuse reflectance (DRS) spectroscopy. The photocatalytic tetracycline (TC) degradation demonstrated that all the AgI/Ag/Cu
3
(BTC)
2
photocatalysts have higher photocatalytic activity than that of pure Cu
3
(BTC)
2
and 20% AgI/Ag/Cu
3
(BTC)
2
has the highest TC degradation efficiency. Moreover, 20% AgI/Ag/Cu
3
(BTC)
2
also has greatly enhanced photocatalytic activities with TC degradation rate 3.41 times and 4.42 times higher than that of AgI/Cu-BTC and Cu-BTC, respectively. A possible indirect Z-scheme mechanism was also proposed according to the trapping experiment and band structures of the photocatalyst. The improved photocatalytic activity of the composite can be attributed to the incorporation of Ag and its Z-scheme structures.
Data hiding is a way of hiding secret data on cover-media and it is used for a variety of applications. An important of the data hiding is to conceal the data in a secret way without loss of ...cover-media. Until now, continuous research on absolute moment block truncation coding based data hiding methods have improved a performance on data concealment and image quality. However, the current absolute moment block truncation coding based data hiding technology has a limitation in deriving a method that significantly surpasses existing performance. In this paper, we propose a new method to overcome this problem. To do this, first the original image is transformed to the cover image using absolute moment block truncation coding and is expanded the image using neighbor average interpolation algorithm. The proposed three data hiding methods are based on the generated cover image. The first method is to directly replace the pixel value, which is a component of each block, with the same secret value. The second method is to replace the pixels to match the secret bits only for the extended pixels in each block of the cover image. The third method is to apply Hamming code to each block to minimize the number of replacement pixels for data hiding. Experimental results show that our method is superior in terms of efficiency compared to traditional absolute moment block truncation coding based data hiding methods.
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