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Background We showed that pomegranate juice (PomJ) can help to maintain memory in adults aged >50 y. The mechanism for this effect is unknown, but might involve Trp and its metabolites, which are important in brain function. Objectives We aimed to test the hypothesis that PomJ and its metabolites ellagic acid (EA) and urolithin A (UA) affect Trp metabolism. Methods Stool and plasma from a cohort [11 PomJ, 9 placebo drink (PL)] of subjects enrolled in our double-blind, placebo-controlled trial (NCT02093130) were collected at baseline and after 1 y of PomJ or PL consumption. In a mouse study, cecum and serum were collected from DBA/2J mice receiving 8 wk of dietary 0.1% EA or UA supplementation. Trp metabolites and intestinal microbiota were analyzed by LC-MS and 16S rRNA gene sequencing, respectively. Results In the human study, the change in the plasma Trp metabolite indole propionate (IPA) over 1 y was significantly different between PomJ and PL groups (P  = 0.03). In serum of experimental mice, we observed a 230% increase of IPA by EA but not UA, a 54% increase of indole sulfate by UA but not EA, and 43% and 34% decreases of kynurenine (KYN) by EA and UA, respectively. In cecum, there was a 32% decrease of Trp by UA but not EA, and an 86% decrease of KYN by EA but not UA (P  < 0.05). The abundance of 2 genera, Shigella and Catenibacterium , was reduced by PomJ in humans as well as by UA in mice, and their abundance was negatively associated with blood IPA in humans and mice (P  < 0.05). Conclusions These results suggest a novel mechanism involving the regulation of host and microbial Trp metabolism that might contribute to the health benefits of ellagitannins and EA-enriched food, such as PomJ. [ABSTRACT FROM AUTHOR]

Ecological security patterns (ESPs) aim to provide an effective spatial approach for maintaining urban ecological security based on the relationship between landscape patterns and ecological processes. However, the methods of selecting ecological security sources and evaluating resistance surfaces for ESPs construction are not well developed and lack consideration of land degradation and spatial heterogeneity. Using Shenzhen City, a fast-growing city in a rapidly urbanizing region, as a case study area, this study evaluated two types of land degradation risk for ecological land: type transformation risk and functional damage risk. Both two kinds of risk were combined with ecological functional importance, which was composed of habitat quality and landscape connectivity, so as to quantify the comprehensive reserve value of ecological land to identify the ecological security sources. Ecological corridors were established with the application of remotely-sensed impervious surface area in the ecological resistance surface evaluation. In all, 477.43 km 2 ecological land were identified as ecological security sources, with 278.1 km and 197.5 km for the length of group corridors and landscape corridors respectively. The ecological corridors spatially presented a radiation pattern of one axis and three strips. The majority of both ecological security sources and corridors was located within the existing ecological protection boundary, confirming its ecological significance. This study provided an effective quantification framework to identify urban ESPs, and ESPs mapping could make a fundamental support to urban planning. [ABSTRACT FROM AUTHOR]

An environmentally friendly approach was reported for recovering vanadium (V) from aqueous media with aqueous two-phase system (ATPS) formed by poly (ethylene glycol) 2000 (PEG2000) and sodium sulfate with octadecyl amine ethoxylate ethers as extractants. The effect of aqueous pH, the type of extractants and phase-forming salts, vanadium concentration and extracting temperature on the extraction performance of vanadium was investigated. The researched results indicated that the extraction rate of vanadium has remarkable relationship with vanadium species in aqueous phase, and the selected extractants can extract efficiently vanadium from salt-rich to PEG200-rich phase. The initial and equilibrium pH in aqueous phase has no relationship with vanadium concentration, and there is no new covalent bond generation between polyvanadate anion and extractant in PEG 2000-rich phase by FTIR, which can be deduced that polyvanadate anion is extracted into PEG 2000-rich phase due to the electrostatic attraction interaction between protonated extractant and polyvanadate anion. Adding chloride and nitrate in aqueous two-phase system could remarkably decrease the extraction rate of vanadium, and then sulfate is in favor of extracting vanadium. The extraction rate of vanadium decreases with increasing temperature from 40.0 °C to 60.0 °C, which showed the phase transfer of vanadium from salt-rich phase to PEG2000-rich phase is exothermal, resulting from the difference of interaction energy among all compositions in aqueous two-phase system. The vanadium can be easily separated out from the solution containing Fe(III), Co(II), Ni(II), Cu(II), Zn (II), Al(III), Cr(III) and Mn(II) under the suitable conditions. The stripping rate and precipitation rate of vanadium can be easily achieved to 90% and 80%, respectively, in single stage stripping with ammonium carbonate solution as stripping agent and phase-forming salt. • An environmentally friendly approach was used for recovering vanadium. • Electrostatic attraction produced between polyvanadate anion and extractant. • Chloride and nitrate inhibit obviously the extraction of vanadium. [ABSTRACT FROM AUTHOR]

• MnO 2 boosted reductive dissolution of As(V)/Fe(III) in illuminated flooded soils. • MnO 2 stimulated production of c -type cytochromes that promoted direct contact based electron transfer. • Suppression of Fe(II) and As(III) resulted from adsorption and oxidation by MnO 2 particles. • MnO 2 -based hybrid microbial-photoelectrochemical technology is a promising remediation strategy for As-polluted soils. This study examined the role of intermittent illumination/dark conditions coupled with MnO 2 -ammendments to regulate the mobility of As and Fe in flooded arsenic-enriched soils. Addition of MnO 2 particles with intermittent illumination led to a pronounced increase in the reductive-dissolution of Fe(III) and As(V) from flooded soils compared to a corresponding dark treatments. A higher MnO 2 dosage (0.10 vs 0.02 g) demonstrated a greater effect. Over a 49-day incubation, maximum Fe concentrations mobilized from the flooded soils amended with 0.10 and 0.02 g MnO 2 particles were 2.39 and 1.85-fold higher than for non-amended soils under dark conditions. The corresponding maximum amounts of mobilized As were at least 92 % and 65 % higher than for non-amended soils under dark conditions, respectively. Scavenging of excited holes by soil humic/fulvic compounds increased mineral photoelectron production and boosted Fe(III)/As(V) reduction in MnO 2 -amended, illuminated soils. Additionally, MnO 2 amendments shifted soil microbial community structure by enriching metal-reducing bacteria (e.g., Anaeromyxobacter , Bacillus and Geobacter) and increasing c -type cytochrome production. This microbial diversity response to MnO 2 amendment facilitated direct contact extracellular electron transfer processes, which further enhanced Fe/As reduction. Subsequently, the mobility of released Fe(II) and As(III) was partially attenuated by adsorption, oxidation, complexation and/or coprecipitation on active sites generated on MnO 2 surfaces during MnO 2 dissolution. These results illustrated the impact of a semiconducting MnO 2 mineral in regulating the biogeochemical cycles of As/Fe in soil and demonstrated the potential for MnO 2 -based bioremediation strategies for arsenic-polluted soils. [ABSTRACT FROM AUTHOR]

Ecological land is an important component of urban ecosystems. Detecting the change of urban ecological land and its driving forces will offer scientific basis for the optimization of urban landscape patterns. The rapid urbanization in Shenzhen City has brought the serious conflicts between socio-economic development and ecological protection. In this study, we characterized ecological land dynamics in Shenzhen City and quantified the driving forces using multivariate logistic regression, and subsequently mapped the transition probability of ecological land. The results showed that in Shenzhen City, urban ecological land had changed dramatically during 1990–2010 in terms of its quantity, quality, and spatial distribution. Land use change matrix between ecological and non-ecological land showed that the area of ecological land decreased more fast during 1990–2000, compared with that during 2000–2010. There was a decrease in area equivalents calculated by the adjustment coefficient of ecosystem services, although the quality per unit was improved. Furthermore, the gravity center of ecological land gradually moved to the southeast. The driving force analysis suggested that the slope, the minimum distance to construction land, and the growth rate of construction land were the vital factors determining the change of urban ecological land. Finally, the transition probability mapping showed that the water body, wetland and grassland near the city center had a higher transition probability to construction land. This study illustrated the change characteristics of urban ecological land, as a result of rapid urbanization. The transition probability can serve as the basis for decision making on constructing urban landscape ecological security pattern. [ABSTRACT FROM AUTHOR]