The Optimization of the Transition Zone of the Planar Heterogeneous Interface for High-Performance Seawater Desalination.

Reverse osmosis has become the most prevalent approach to seawater desalination. It is still limited by the permeability-selectivity trade-off of the membranes and the energy consumption in the operation process. Recently, an efficient ionic sieving with high performance was realized by utilizing the bi-unipolar transport behaviour and strong ion depletion of heterogeneous structures in 2D materials. A perfect salt rejection rate of 97.0% and a near-maximum water flux of 1529 L m-2 h-1 bar-1 were obtained. However, the energy consumption of the heterogeneous desalination setup is a very important factor, and it remains largely unexplored. Here, the geometric-dimension-dependent ion transport in planar heterogeneous structures is reported. The two competitive ion migration behaviours during the desalination process, ion-depletion-dominated and electric-field-dominated ion transport, are identified for the first time. More importantly, these two ion-transport behaviours can be regulated. The excellent performance of combined high rejection rate, high water flux and low energy consumption can be obtained under the synergy of voltage, pressure and geometric dimension. With the appropriate optimization, the energy consumption can be reduced by 2 orders of magnitude, which is 50% of the industrial energy consumption. These findings provide beneficial insight for the application and optimized design of low-energy-consumption and portable water desalination devices.

Study on Irradiation Response of Nanocrystalline Phase in Sm-Doping Fluorapatite Glass-Ceramics under He Ion Irradiation.

Two different of Sm-loading fluorapatite (Ca10-2xNaxSmx(PO4)6F2, x = 1 and 2) glass-ceramics were synthesized by a two-step melt sintering method. The samples were irradiated with 50 keV He+ ions with a fluence of 2.6 × 1016 ions/cm2 at 593 K. The irradiation induced microstructural evolution were characterized by grazing incidence X-ray diffraction and cross-sectional transmission electron microscopy. For the smaller Sm-doping samples, no phase transformation is observed. Meanwhile, in the lager Sm-doping samples, the irradiation induced the crystals into smaller nanocrystals. The mechanism of the transformation of the crystalline phase was also analyzed and discussed.

Vertically-Oriented Ti3C2Tx MXene Membranes for High Performance of Electrokinetic Energy Conversion.

The electrokinetic effect to convert the mechanical energy from ambient has gained sustained research attention because it is free of moving parts and easy to be miniaturized for microscale applications. The practical application is constrained by the limited electrokinetic energy conversion performance. Herein, we report vertically oriented MXene membranes (VMMs) with ultrafast permeation as well as high ion selectivity, in which the permeation is several thousand higher than the largely researched horizontally stacked MXene membranes (HMMs). The VMMs can achieve a high streaming current of 8.17 A m-2 driven by the hydraulic pressure, largely outperforming all existing materials. The theoretical analysis and numerical calculation reveal the underlying mechanism of the ultrafast transport in VMMs originates from the evident short migration paths, the low energy loss during the ionic migration, and the large effective inlet area on the membrane surface. The orientation of the 2D lamella in membranes, the long-overlooked element in the existing literatures, is identified to be an essential determinant in the performance of 2D porous membranes. These understandings can largely promote the development of electrokinetic energy conversion devices and bring advanced design strategy for high-performance 2D materials.

Gut mycobiota and adenomas.

Fungal microbiota (mycobiota) is potentially involved in the intestinal illness. The characterization of the mycobiota in patients with adenomas is essential for understanding the etiology of the pre-cancerous lesion since the mycobiota is potentially associated with the presents of adenomas. The recovery of the mycobiome may also help to identify the potential biomarkers which may closely relate to different stages of adenoma.

Dysbiosis of fungal microbiota in the intestinal mucosa of patients with colorectal adenomas.

The fungal microbiota is an important component of the human gut microbiome and may be linked to gastrointestinal disease. In this study, the fungal microbiota of biopsy samples from adenomas and adjacent tissues was characterized by deep sequencing. Ascomycota, Glomeromycota and Basidiomycota were identified as the dominant phyla in both adenomas and adjacent tissues from all subjects. Among the 60 genera identified, the opportunist pathogens Phoma and Candida represented an average of 45% of the fungal microbiota. When analyzed at the operational taxonomic unit (OTU) level, however, a decreased diversity in adenomas was observed, and three OTUs differed significantly from the adjacent tissues. Principal Component Analysis (PCA) revealed that the core OTUs formed separate clusters for advanced and non-advanced adenomas for which the abundance of four OTUs differed significantly. Moreover, the size of adenomas and the disease stage were closely related to changes in the fungal microbiota in subjects with adenomas. This study characterized the fungal microbiota profile of subjects with adenomas and identified potential diagnostic biomarkers closely related to different stages of adenomas.

[Quantitation of intestinal Fusobacterium and butyrate- producing bacteria in patients with colorectal adenomas and colorectal cancer].

OBJECTIVE: To compare the abundance of 16S rRNA gene of intestinal Fusobacterium and butyrate-producing bacteria in patients with colorectal adenomas patients and colorectal cancer and to reveal the correlation between the target bacteria and the development of colorectal cancer. METHODS: Feces were collected from colorectal cancer patients (n=19), colorectal adenomas patients (n=12) and healthy subjects (n=19). Bacteria genome DNA from the fecal samples was used to quantitate the Fusobacterium, two butyrate-producing bacteria Eubacterium rectal, Faecalibacterium prausnitzii and total bacteria by real-time polymerase chain reaction. Then the variation of the target bacteria among different groups were assayed using Mann-Whitney U test. RESULTS: The abundance of Fusobacterium was significantly higher in colorectal cancer patients than that in healthy subjects (P = 0.000) and colorectal adenomas patients (P = 0.013), and it was significantly higher in colorectal cancer patients than that in colorectal adenomas patients (P = 0.002). F. prausnitzii was significantly lower in colorectal adenomas patients compared to healthy subjects (P = 0.033). The total bacteria count was significantly lower in the colorectal adenomas samples than that in the healthy samples (P = 0.002). There was no significantly difference of E. rectal between the three groups. CONCLUSIONS: The shifts in the colonic bacterial population may potentially contribute to the development of colorectal cancer.