Analyzing international airtime top-up transfers for migration and mobility.

International airtime top-up transfers enable prepaid mobile phone users to send top-ups and data bundles to users in other countries, as well as make payments, in real time. These are heavily used by migrants to financially assist their families in their home countries and consequently could be a valuable source of information for migration and mobility analysis. However, top-up transfers are understudied as a form of money remittance in migration. In this paper, we explore the determinants and the potential of top-up transactions to complement remittance and migration statistics. Our results show that such data can provide insights into migrant groups, particularly for irregular migration and for estimating the real-time distribution of migrant groups for a given country.

Caffeic acid-grafted-chitosan/polylactic acid film packaging enhances the postharvest quality of Agaricus bisporus by regulating membrane lipid metabolism.

In this study, the film assembled by caffeic acid-grafted-chitosan/polylactic acid (CA-g-CS/PLA) was used for packaging postharvest Agaricus bisporus, and its effects on postharvest quality of Agaricus bisporus by regulating membrane lipid metabolism were investigated. The results showed that compared to traditional polyethylene packaging, the cell morphology of Agaricus bisporus packaged by CA-g-CS/PLA demonstrated a more complete structure due to its lower permeability, higher fluidity and stronger ability to maintain free water. Meanwhile, CA-g-CS/PLA packaging could effectively delay the decrease rate of unsaturation value and phospholipids of Agaricus bisporus during storage. In addition, the activities and expression levels of lipoxygenase (LOX), phospholipase C (PLC) and phospholipase D (PLD) in Agaricus bisporus packaged with CA-g-CS/PLA were inhibited, while those of glycerol-3-phosphate acyltransferase (GPAT) and sphingomyelin synthase (SMS) were promoted. Therefore, CA-g-CS/PLA packaging could enhance the postharvest quality of Agaricus bisporus by regulating membrane lipid metabolism, which has great application potential in the field of new intelligent packaging.

Facile in situ formation of a ternary 3D ZnIn2S4-MoS2 microsphere/1D CdS nanorod heterostructure for high-efficiency visible-light photocatalytic H2 production.

To achieve high photocatalytic efficiency, developing heterostructure photocatalysts by integrating two or more semiconductor materials into a well-oriented nanostructure is an effective strategy. Therefore, under visible light irradiation, a novel ternary 3D ZnIn2S4-MoS2 microsphere/1D CdS nanorod (ZIS/MoS2/CdS) photocatalyst with excellent H2 evolution ability was prepared. For this purpose, using the solvothermal method, interfacial contact ZIS/MoS2 microspheres were prepared, and 1D CdS nanorods were closely inserted into the interspace of flower-shaped ZIS/MoS2 microspheres, to generate close contact between ZnIn2S4, MoS2, and CdS. To expedite the production, separation, and transfer of photoinduced electron-hole pairs, this unique ternary heterostructure demonstrated excellent energy level distribution and a dimensional structure. Under the same conditions, the H2 production rate of the component proportion of the 150%-ZIS/10%-MoS2/CdS (150 wt% ZIS and 10 wt% MoS2) photocatalyst reached 7570.4 µmol g-1 h-1, which was ∼39.8 and 69.0 times higher than that achieved using bare ZnIn2S4 and CdS, respectively. Furthermore, the apparent quantum efficiency (AQE) reached 30.38% at 420 nm within 6 h; thus, for designing photocatalysts with a diversiform structure and spatial charge separation, this study provides new tactics.

BiOBr nanoplates@TiO2 nanowires/carbon fiber cloth as a functional water transport network for continuous flow water purification.

A novel BiOBr@TiO2/carbon hybrid framework as a continuous flow sunlight water purification system has been reported in the present work. The BiOBr@TiO2/carbon hybrid framework was fabricated via the sequential growth of TiO2 nanowires and BiOBr nanoplates on carbon fiber cloth. TiO2 nanowires interweaved with carbon fibers to form a porous network, while BiOBr nanoplates were arrayed on TiO2 nanowires. The obtained BiOBr@TiO2/carbon hybrid framework possesses numerous micro/nanochannels between their adjacent one-dimensional building blocks, which can serve as an effective water transport network driven by capillary force. Furthermore, BiOBr@TiO2/carbon hybrid frameworks exhibit impressive sunlight-driven photocatalytic activity and adsorption ability because of their enhanced sunlight absorption ability, efficient charge separation features, and mesoporous architecture. The excellent reusability and durability of the BiOBr@TiO2/carbon hybrid frameworks have also been confirmed. A novel BiOBr@TiO2/carbon hybrid framework based continuous flow sunlight water purification system with a high water purification efficiency (305.6 L h-1 m-2) has been constructed in the present work. All the features make the BiOBr@TiO2/carbon hybrid framework a promising material suitable for water purification.

Optimization of enzyme-assisted extraction and characterization of collagen from Chinese sturgeon (Acipenser sturio Linnaeus) skin.

BACKGROUND: Sturgeon (Acipenser sturio Linnaeus) skin contains high amount of nutrients including unsaturated fatty acids and collagen. A pepsin-assisted extraction procedure was developed and optimized for the extraction of collagen from Chinese sturgeon (Acipenser sturio Linnaeus) skins. OBJECTIVE: To determine the optimum conditions with the maximum yield of the pepsin-soluble collagen (PSC) extraction. MATERIALS AND METHODS: The conditions of the extraction were optimized using response surface methodology. The Box-Behnken design was used to evaluate the effects of the three independent variables (extraction time, enzyme concentration, and solid-liquid ratio) on the PSC yield of the sturgeon skin. RESULTS: THE OPTIMAL CONDITIONS WERE: solid-liquid ratio of 1:11.88, enzyme concentration of 2.42%, and extraction time of 6.45 h. The maximum yield of 86.69% of PSC was obtained under the optimal conditions. This value was not significantly different from the predicted value (87.4%) of the RSM (P < 0.05). CONCLUSION: The results of this study indicated that the production of PSC from sturgeon skin is feasible and beneficial. The patterns of sodium dodecyl sulfate-polyacrylamide gel electrophoretic patterns (SDS-PAGE) indicated that the sturgeon skin contains type I collagen, which is made of α-chain and ß-chain. The infrared spectra of the collagens also indicated that pepsin hydrolysis does not affect the secondary structure of collagen, especially triple-helical structure.

Extraction, purification and characterisation of chondroitin sulfate in Chinese sturgeon cartilage.

BACKGROUND: Chinese sturgeon (Acipenser sinensis), a rare species, is an important fishery resource in China. To save this species from overfishing, damming and pollution, artificial propagation has been developed rapidly in recent years. However, the cartilage from Chinese sturgeon, which contains an abundance of chondroitin sulfate (CS), is currently discarded as solid waste after consumption of the fish. The aim of this study was to investigate the extraction, purification and characterisation of CS from Chinese sturgeon cartilage. RESULTS: The optimal extraction parameters were a ratio of aqueous NaOH to cartilage powder of 9.2, a concentration of aqueous NaOH of 4.4% and an extraction time of 3.9 h. Under these optimal conditions the yield of crude CS from Chinese sturgeon cartilage was 26.51%, in agreement with the model prediction (26.54%). Purification by DEAE-52 cellulose and Sephadex G-100 column chromatography yielded a single fraction, CS-11. Its characterisation indicated that CS-11 was consistent with the polysaccharide backbone structure -4GlcAß-3GalNß- and was present in the form of chondroitin-4-sulfate and chondroitin-6-sulfate. CONCLUSION: The results of this study provide a basis for promoting the utilisation of Chinese sturgeon resources and are significant for the development and utilisation of CS from Chinese sturgeon cartilage in the food industry.