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Taste and odor (T/O) compounds are a global threat in drinking water, mainly produced by cyanobacteria in freshwater environments. Temperature plays a crucial role in regulating geosmin dynamics in temperate and subtropical lakes, while its influence may be lower in tropical waters. To better understand the factors affecting geosmin occurrence in tropical waters, a dataset from a field investigation conducted in a large tropical reservoir was analyzed. The water temperature varied between 16 °C and 32 °C, with geosmin concentration ranging from below the detection limit (3 ng/L) to as high as 856 ng/L. Elevated geosmin levels exceeding > 10 ng/L were observed over the whole year except for in September, suggesting that the annual temperature was suitable for geosmin production. Among the diverse cyanobacteria, Dolichospermum circinale was identified as the main producer of geosmin in the reservoir, both by correlation analysis and cells' geosmin measurements. Geosmin concentration was also significantly related to the abundance of D. circinale. None of the environmental variables (temperature, pH, transparency and nutrients) were significantly directly correlated with geosmin concentration. But the high total nitrogen significantly explained the increase in D. circinale abundance associated with geosmin elevation. Our results suggest that nutrients, particularly nitrogen, directly affected the competitive advantage and abundance of key geosmin producers and thus modified geosmin levels in this tropical reservoir. Our study thus hints at the possible management of the geosmin problem through nutrient reduction in tropical reservoirs. [ABSTRACT FROM AUTHOR]

Heart failure (HF) constitutes a major determinant of outcome in chronic kidney disease (CKD) patients. The main pattern of HF in CKD patients is preserved ejection fraction (HFpEF), and left ventricular diastolic dysfunction (LVDD) is a frequent pathophysiological mechanism and specific preclinical manifestation of HFpEF. Therefore, exploring and intervention of the factors associated with risk for LVDD is of great importance in reducing the morbidity and mortality of cardiovascular disease (CVD) complications in CKD patients. We designed this retrospective cross-sectional study to collect clinical and echocardiographic data from 339 nondialysis CKD patients without obvious symptoms of HF to analyze the proportion of asymptomatic left ventricular diastolic dysfunction (ALVDD) and its related factors associated with risk by multivariate logistic regression analysis. Among the 339 nondialysis CKD patients, 92.04% had ALVDD. With the progression of CKD stage, the proportion of ALVDD gradually increased. The multivariate logistic regression analysis revealed that increased age (OR 1.237; 95% confidence interval (CI) 1.108–1.381, per year), diabetic nephropathy (DN) and hypertensive nephropathy (HTN) (OR 25.000; 95% CI 1.355–48.645, DN and HTN vs chronic interstitial nephritis), progression of CKD stage (OR 2.785; 95% CI 1.228–6.315, per stage), increased mean arterial pressure (OR 1.154; 95% CI 1.051–1.268, per mmHg), increased urinary protein (OR 2.825; 95% CI 1.484–5.405, per g/24 h), and low blood calcium (OR 0.072; 95% CI 0.006–0.859, per mmol/L) were factors associated with risk for ALVDD in nondialysis CKD patients after adjusting for other confounding factors. Therefore, dynamic monitoring of these factors associated with risk, timely diagnosis and treatment of ALVDD can delay the progression to symptomatic HF, which is of great importance for reducing CVD mortality, and improving the prognosis and quality of life in CKD patients. [ABSTRACT FROM AUTHOR]

Filter-feeding bivalves have strong effects on ecosystem processes and functions. Bivalves may be used for the rehabilitation of eutrophic waters, either by being placed suspended in cages or on chains in pelagic habitats or stocked in benthic habitats. However, the effects of bivalves on the ecosystem may differ between the two habitats. A 5-week mesocosm experiment with bivalves (Sinanodonta woodiana Lea 1834) was conducted to test if filter-feeding bivalves suspended in pelagic habitats would improve water quality more efficiently than stocked bivalves in benthic habitats. Nutrients, suspended solids, light intensity, biomass of phytoplankton in different size fractions, and zooplankton were measured. Bivalves reduced the biomasses of total phytoplankton and nanophytoplankton and decreased the total phosphorus, total suspended solids, and organic suspended solids in both the benthic and the pelagic habitats. Bivalves also increased the light intensity and the biomass of periphyton and benthic algae. However, we found significantly higher ammonium nitrogen concentrations and higher periphyton biomass in the suspended bivalve treatment than in the benthic bivalve treatment. In both habitats, bivalve introduction reduced the abundance of cladocerans, increased the abundance of copepods but had no effect on the abundance of rotifers. The abundances of total zooplankton, cladocerans, copepods, and rotifers were similar in the treatments with suspended and benthic bivalves. These results confirm the strong effect of filter-feeding bivalves on plankton communities and their potential for the improvement of water quality whether suspended or occurring in the sediment, they indicate a potential of using filter-feeding bivalves in lake rehabilitation. [ABSTRACT FROM AUTHOR]

Ethanol can directly or indirectly lead to cognitive and mental disorders. The long‐term intake of alcohol can directly affect the distribution of gut microbiota. Lactobacillus rhamnosus GG (LGG) is a natural bacterium isolated from healthy human intestines that has the function of preventing cytokine‐induced cell apoptosis and protecting cell barriers. However, the regulatory effect of LGG on cognitive and mental disorders caused by chronic ethanol exposure (CEE) is still unclear. In this study, we established a CEE mouse model through free alcohol consumption and added LGG or antibiotics in the later stages of the model. Sequencing analysis of the 16S rRNA gene showed that CEE resulted in a decrease in the abundance and diversity of mouse gut microbial communities accompanied by alterations in the relative abundance of multiple enterobacterial genera. The use of LGG and antibiotics alleviated the depression‐like behaviour and cognitive impairment of CEE‐induced mice, reduced expression of inflammatory factors such as interleukin (IL)‐6, IL‐1β and tumour necrosis factor (TNF)‐α in the ileum, serum and brain and increased the expression of synaptophysin (SYN), postsynaptic density protein‐95 (PSD‐95) and brain‐derived neurotrophic factor (BDNF) in the hippocampus. Together, LGG can alleviate depression‐like behaviour caused by CEE in mice while also improving cognitive and memory functions through reducing peripheral and nervous system inflammation factors and balancing gut microbiota. [ABSTRACT FROM AUTHOR]

Existing research provides mixed insights regarding social media's (SM) effect on new product advantage (NPA). We emphasise on this inconsistency by focusing on the fact SM has different effects on two kinds of NPA: new product development speed (NPD speed) and new product creativity (NPC). We suggest that SM can boost NPD speed and yet have an inverted U-shaped effect on NPC. Furthermore, we argue that top management team diversity (TMT diversity) enhances the effects of SM on NPA. We verify and provide evidence to support our hypotheses using 150 sample firms based in China. This study highlights the NPA trade-offs related to SM and provides crucial theoretical contributions and managerial implications. [ABSTRACT FROM AUTHOR]

Regenerated cellulose membrane is a biomaterial obtained by activating, dissolving, solidifying, and regenerating cellulose powder using solvents of different polarities. It has the characteristics of high oxygen resistance and high strength. However, its low water vapor barrier and single function limit its application. In order to improve the water resistance of regenerated cellulose membranes and endow them with UV resistance, lignin was extracted from waste wheat straw using formic acid method. The extracted formic acid lignin (FAL) was added to the cellulose solution to prepare a series of regenerated lignocellulosic membranes (RC‐FAL) with different lignin contents. The results indicate that lignin can not only improve the water vapor barrier, tensile strength, and water resistance of the film, but also enhance the oxygen barrier and UV absorption of the film. Compared with pure cellulose film, the contact angle of lignocellulose film can be increased by 66.2%, the UV absorption rate can reach 100%, and the oxygen transmission coefficient has no significant effect. In this paper, a new kind of biological packaging material with high oxygen resistance, strong ultraviolet absorption, and water resistance was prepared by recycling waste wheat straw, it has a broad application prospect in the industrial production of packaging materials. [ABSTRACT FROM AUTHOR]

This research attempts to fabricate a novel type of pressure‐sensitive adhesive (PSA) tape utilizing epoxidized linseed oil (ELO) as the primary component in an effort to reduce reliance on petrochemical polymers. This raw material comes from the natural renewable resources, making this tape a more environmentally friendly choice in reducing impact on the environment and alleviating resource pressure. The ester groups on ELO are subjected to hydrolysis in order to yield a combination of epoxy linseed oil fatty acids (ELFAs) containing both epoxy and carboxyl groups. By controlling the temperature and catalyst conditions, the epoxy and carboxyl groups undergo a ring‐opening reaction, resulting in the self‐polymerization of the ELFA mixture and the formation of hydroxy‐functionalized polymers. These polymers are then applied as a coating on kraft paper and subsequently cut to produce PSA tapes. The tapes produced using this method exhibit a peak peel strength of 20.538 N per 25 mm. Moreover, the incorporation of glycerol ester of rosin serves to enhance the peel strength, resulting in a higher value of 21.883 N per 25 mm. The utilization of sealing the cardboard box by the tapes also serves as validation for the immense capabilities of the tapes in practical applications. [ABSTRACT FROM AUTHOR]

In this work, a PE‐based antibacterial and antioxidant material was successfully developed. L‐Ascorbic acid and p‐hydroxybenzoic acid were used as raw materials to synthesize L‐ascorbic acid‐p‐hydroxybenzoate (LPHB) by direct esterification method. LPHB was added to polyvinyl alcohol (PVA) solution and coated on corona‐treated low‐density polyethylene (LDPE) film coated with primer layer to prepare a composite film. The effects of different concentrations of LPHB on the performance of composite films were investigated to determine the optimal amount of addition, and then to prepare both antibacterial and antioxidant films. The antimicrobial properties of LPHB were analysed. The antibacterial, antioxidant, mechanical, barrier properties and morphology of the films were characterized and analysed. The results showed that the addition of LPHB significantly improved the antibacterial and anti‐mould properties, oxidation resistance, and barrier properties of the composite film compared to the LDPE film. The best overall performance of the composite film was achieved when the content of LPHB was 1.5%, the antibacterial rate against Escherichia coli and Staphylococcus aureus reached 99%, and the free radical scavenging rate reached 67.22%. In addition, the cling film added with LPHB has better antioxidant and antibacterial properties, which has obvious effect on bread preservation and has potential for application in food packaging. [ABSTRACT FROM AUTHOR]

Biological invasions are among the most serious threats to ecosystems. The golden apple snail Pomacea canaliculata (Lamarck, 1822) is considered one of the top 100 worst invasive alien species in the world. These snails consume benthic primary producers, including submerged macrophytes, which may lead to an increase in nutrient concentration in the water, enhance growth of phytoplankton, and decrease growth of macrophytes, thereby shifting the primary production from benthic to pelagic habitats in shallow systems. To test this hypothesis, we conducted a short-term experiment with and without the invasive P. canaliculata in mesocosms with high abundance of the native submerged macrophyte Vallisneria natans (Lour.) Hara. Compared with snail-free control, the snail increased the concentrations of total nitrogen (TN), nitrate nitrogen (NO3−–N), total and organic suspended solids (TSS and OSS), decreased the concentrations of soluble reactive phosphorous (SRP), but had no effect on total phosphorus (TP) and the TN:TP ratio. In addition, the snails decreased the biomass, leaf length and tiller number of V. natans, and decreased light intensity. Although snail presence did not change the biomasses of nanophytoplankton and picophytoplankton, it did increase the biomass of microphytoplankton leading to an increase in total phytoplankton biomass. Our study shows that P. canaliculata shifted primary production from benthic to pelagic habitats, altered the phytoplankton community size structure, and decreased water quality. The results add further evidence of negative ecosystem impacts of this invasive apple snail and call for its control in invaded shallow lake ecosystems. [ABSTRACT FROM AUTHOR]

Heart failure (HF) constitutes a major determinant of outcome in chronic kidney disease (CKD) patients. The main pattern of HF in CKD patients is preserved ejection fraction (HFpEF), and left ventricular diastolic dysfunction (LVDD) is a frequent pathophysiological mechanism and specific preclinical manifestation of HFpEF. Therefore, exploring and intervention of the factors associated with risk for LVDD is of great importance in reducing the morbidity and mortality of cardiovascular disease (CVD) complications in CKD patients. We designed this retrospective cross-sectional study to collect clinical and echocardiographic data from 339 nondialysis CKD patients without obvious symptoms of HF to analyze the proportion of asymptomatic left ventricular diastolic dysfunction (ALVDD) and its related factors associated with risk by multivariate logistic regression analysis. Among the 339 nondialysis CKD patients, 92.04% had ALVDD. With the progression of CKD stage, the proportion of ALVDD gradually increased. The multivariate logistic regression analysis revealed that increased age (OR 1.237; 95% confidence interval (CI) 1.108–1.381, per year), diabetic nephropathy (DN) and hypertensive nephropathy (HTN) (OR 25.000; 95% CI 1.355–48.645, DN and HTN vs chronic interstitial nephritis), progression of CKD stage (OR 2.785; 95% CI 1.228–6.315, per stage), increased mean arterial pressure (OR 1.154; 95% CI 1.051–1.268, per mmHg), increased urinary protein (OR 2.825; 95% CI 1.484–5.405, per g/24 h), and low blood calcium (OR 0.072; 95% CI 0.006–0.859, per mmol/L) were factors associated with risk for ALVDD in nondialysis CKD patients after adjusting for other confounding factors. Therefore, dynamic monitoring of these factors associated with risk, timely diagnosis and treatment of ALVDD can delay the progression to symptomatic HF, which is of great importance for reducing CVD mortality, and improving the prognosis and quality of life in CKD patients. [ABSTRACT FROM AUTHOR]

In temperate shallow lakes, submerged macrophytes facilitate zooplankton development by providing refuge against fish predation and, thereby, indirectly contribute to maintaining a clear-water state through enhanced zooplankton grazing. The role of macrophytes for zooplankton and their grazing potential is less clear for tropical lakes. We investigated crustacean zooplankton in a phytoplankton-dominated basin (algal basin) and two restored basins dominated by macrophytes (macrophyte basins) in the shallow Huizhou West Lake in tropical southern China. We found that copepods prevailed in all basins, but the dominant taxon differed, with omnivorous cyclopoids dominating in the algal basin and herbivorous calanoids in the macrophyte basins. Moreover, the biomass ratios of calanoid:copepod and zooplankton:phytoplankton were higher in the macrophyte basins than in the algal basin. Our results suggest that restoration measures involving macrophyte transplantation and fish removal lead to reduced fish predation on zooplankton, which help to maintain the clear-water state when macrophytes are established due to higher control on phytoplankton. However, unlike in temperate lakes, large-bodied Daphnia were generally absent and the zooplankton:phytoplankton ratio was overall low, indicating a weaker top-down control in tropical lakes, which is likely due to higher fish predation. [ABSTRACT FROM AUTHOR]

Submerged macrophytes play crucial roles in maintaining the stability of clear-water states in shallow lakes. Recent stable isotope studies have shown that crustacean zooplankton can utilize submerged macrophyte carbon, but macrophytes alone cannot support the growth and reproduction of such grazers, being deficient in highly unsaturated fatty acids (HUFA). We hypothesized that flagellates feeding on macrophytes can synthesize HUFA and thereby support crustacean zooplankton. To test this hypothesis, we conducted a feeding experiment in which Daphnia magna were provided with a diet of submerged macrophyte Hydrilla verticillata detritus which had been degraded by lake microbes. The chlorophyte Scenedesmus bijuga and undegraded macrophyte detritus were used as controls for comparison of Daphnia's performance. Using biochemical analysis, we examined how the degradation process affected the food quality of the macrophyte. Flagellates were subsequently isolated from the degraded macrophyte and cultured heterotrophically to detect their HUFA synthesis. The 5-day degraded H. verticillata showed significantly higher HUFA concentrations than undegraded macrophyte detritus. They supported better Daphnia performance than undegraded macrophyte, being comparable with S. bijuga. Two isolated flagellates (SL-1 and SL-2), identified as Ochromonas sp. and Poterioochromonas sp., were found to contain HUFA when cultured heterotrophically without dietary sources of fatty acids, suggesting their HUFA synthesis ability. Our results demonstrate that submerged macrophytes may thus indirectly support crustacean zooplankton via flagellate mediation. As crustacean zooplanktons are of key importance for water quality in the grazer control of phytoplankton, this microbial facilitation may contribute to the maintenance of macrophyte clear-water conditions in shallow lakes. [ABSTRACT FROM AUTHOR]

Organic carbon derived from terrestrial plants contributes to aquatic consumers, e.g., zooplankton in lakes. The degree of the contribution depends on the availability of terrestrial organic carbon in lake organic pool and the transfer efficiency of the carbon. Terrestrial organic carbon is poor-quality food for zooplankton with a mismatch of nutrition content and was incorporated to zooplankton with much lower efficiency than phytoplankton. Contributions of terrestrial carbon to zooplankton generally decrease with an increase in phytoplankton production, indicating a preferential incorporation of phytoplankton in previous investigations. However, in eutrophic lakes, the dominating cyanobacteria were of poor quality and incorporated to consumers inefficiently too. In that case, zooplankton in eutrophic wetlands, where cyanobacteria dominate the phytoplankton production and massive terrestrial plants are inundated, may not preferentially incorporate poor food-quality phytoplankton resource to their biomass. Therefore, we hypothesize that carbon contributions of terrestrial vegetation to zooplankton and to lake particulate organic pool should be similar in such aquatic ecosystems. We tested this hypothesis by sampling zooplankton and carbon sources in Ming Lake (Jinan University Campus, southern China) which was overgrown by terrestrial plants after drying and re-flooded. After 60 days of observations at weekly (or biweekly) intervals, applying stable carbon (13C), nitrogen (15 N), and hydrogen (2H) isotopic analysis and a stable isotope mixing model, we estimated the occurrence of extensive carbon contribution (≥ 50%) of flooded terrestrial plants to cladocerans and copepods. Contribution of inundated terrestrial plants to cladocerans was similar to that to lake particulate organic pool. Thus, our study quantified the role of terrestrial carbon in eutrophic wetlands, enhancing our understanding of cross-ecosystem interactions in food webs with an emphasis on the resource quality. [ABSTRACT FROM AUTHOR]

As the most common cardiovascular disease, atherosclerosis (AS), is a leading cause of high mortality in patients with chronic renal failure. Rab27a has been reported to regulate the progression of cardiovascular and renal diseases. Nevertheless, little studies investigated the role and mechanism of Rab27a in uremic-accelerated AS (UAAS). An animal model of UAAS was established in apolipoprotein E knockout (apoE−/−) mice using 5/6 nephrectomy (NX). We conducted in vitro and in vivo functional experiments to explore the role of Rab27a in UAAS, including the presence of oxidized low-density lipoprotein (ox-LDL). Rab27a expression was upregulated in the plaque tissues of NX apoE−/− mice. The knockout of Rab27a (Rab27a−/−) reduced AS-induced artery injury, as manifested by the reductions of plaque area, collagen deposition, inflammation and lipid droplet. Besides, cholesterol efflux was increased, while the expression of lipid metabolism-related proteins and the secretions of pro-inflammatory factors were decreased in ox-LDL-induced NX Rab27a−/−apoE−/− mice group. Further, Rab27a deletion inhibited the activation of nuclear factor κB (NF-κB) pathway. In conclusion, our study indicated that Rab27a deficiency attenuated foam cell formation and macrophage inflammation, depending on the NF-κB pathway activation, to inhibit AS progression in uremic apoE−/− mice. This finding may provide a new targeting strategy for UAAS therapy. [ABSTRACT FROM AUTHOR]

Terrestrial inputs of dissolved organic matter (DOM) stimulate microbial growth by supplying organic carbon and DOM‐associated nutrients, and thus increase food availability for zooplankton. Terrestrial inputs of DOM might decrease the content of eicosapentaenoic acid (EPA) in particular organic matter (POM) due to an increase in biomass of EPA‐poor microbes, for example, heterotrophic bacteria and autotrophic cyanobacteria, thereby reducing food quality and filter‐feeding zooplankton's biomass. We performed a 26‐d mesocosm experiment where terrestrial DOM was manipulated by adding (treatments) and kept without adding (controls) 13C‐labeled maize leachate to evaluate the effect of food quality changes induced by terrestrial DOM inputs on zooplankton. DOM addition treatments had significantly higher concentrations of POM and Chlorophyll a relative to controls, but significant lower EPA content of POM, responding to increased biomass of bacteria and chlorophytes. Biomass and EPA content of filter‐feeding cladoceran Chydorus sphaericus was significantly reduced by terrestrial DOM addition. Stable isotope analyses showed 13C enrichments in bacteria and cryptophytes in the treatment of 13C‐labeled maize leachate, indicating a growth stimulation of heterotrophic microbes by organic carbon addition. Although the 13C enrichment in Chydorus evidenced the extensive use of terrestrial DOM by this cladoceran, positive relationships between Chydorus biomass and EPA content of POM suggest that terrestrial DOM inputs increase food quality constrains on filter‐feeding zooplankton. Our study suggests that the response of filter‐feeding zooplankton to inputs of terrestrial DOM depends on how the terrestrial inputs change the microbial communities and thus the food quality in the receiving aquatic ecosystems. [ABSTRACT FROM AUTHOR]

A transparent, bendable, high oxygen barrier cellulose‐based film was prepared, which has far better oxygen barrier properties than conventional polyethylene, polypropylene and cellophane materials. A series of regenerated cellulose films (RCs) were prepared from filter paper lacking oxygen barrier properties under different cellulose concentrations and gelation times. It was shown that the cellulose concentration and gel time had a greater effect on the oxygen barrier properties of RCs. When the cellulose concentration was 4 wt% and the gel time was 3 h, the RCs obtained the lowest oxygen permeability coefficient (OPC) down to 2.21 × 10−17 cm3 cm cm−2 s−1 Pa−1. The films have a tensile strength of 109.5 MPa, an elongation at break of 27.3% and a light transmission rate of 89%. In further, molecular dynamics simulations showed that when the filter paper was converted to RCs, the increase in hydrogen bonding and the decrease in free volume between cellulose chains caused a decrease in the diffusion coefficient of oxygen. As a novel biobased high oxygen barrier material, the film has broad application prospect in packaging and chemical industry. [ABSTRACT FROM AUTHOR]

Nile tilapia is a highly invasive fish species, deliberately introduced into many lakes and reservoirs worldwide, sometimes resulting in significant ecosystem alterations. A short-term mesocosm experiment with and without Nile tilapia (Oreochromis niloticus) was designed to test the hypotheses that the presence of tilapia may affect phytoplankton community structure, increase nutrients availability in water column and deteriorate water quality. Nutrients, total suspended solids (TSS) and biomass of phytoplankton in different size classes (as Chl a) were measured. We found that tilapia increased the total nitrogen (TN), total dissolved nitrogen (TDN), NH4+ and TSS concentrations, deteriorating the water quality. In addition, under tilapia presence, the biomass of phytoplankton, as well as that of micro- and nano-phytoplankton, increased leading to a change in the structure of the phytoplankton assemblage. Moreover, a reduction in the biomass of periphyton was observed. Omnivorous tilapia is often dominant in tropical and subtropical waters, and removal of this fish may represent an effective management tool to improve the water quality. [ABSTRACT FROM AUTHOR]

Submerged macrophytes cannot be utilized directly by zooplankton. However, vegetation can serve as an organic carbon resource for heterotrophic bacteria, which are themselves accessible to zooplankton. We therefore hypothesize that submerged macrophytes supply a carbon source to zooplankton by increasing the availability of food such as heterotrophic bacteria. Here, we used stable carbon isotope (13C) labeling to trace the carbon flow from submerged macrophytes to zooplankton with a mesocosm experiment. The carbon stable isotope ratios of zooplankton and their potential food sources were analyzed in mesocosms planted with 13C-labeled Hydrilla verticillata (L. f.) Royle in comparison with the control in which plastic plants were planted. We found that all potential food resources of zooplankton, including phytoplankton, bacterioplankton, macrophyte-associated epiphyton and epibacteria, were significantly enriched with 13C in the presence of 13C-enriched H. verticillata. Zooplankton were significantly more enriched with 13C than phytoplankton, epiphyton and bacterioplankton but significantly less enriched with 13C than epibacteria. Based on a stable isotopic mixing model, we found a macrophyte carbon contribution of 30.5% to epibacteria and 14.7% to zooplankton. Our results indicated that macrophytes might be used by zooplankton as a carbon resource, mainly via a pathway involving epibacteria attached to macrophytes. [ABSTRACT FROM AUTHOR]

BACKGROUND The importance of monoterpenes in grape and wine aroma has compelled researchers to focus on developing methods to increase their abundance. Recent research has revealed that exogenous elicitors can increase the contents of these compounds. This study determined the effects of methyl jasmonate (MeJA) preharvest treatments on the monoterpene profiles of Muscat Hamburg grapes and wine. RESULTS: A total of 27 monoterpenes were identified for Muscat Hamburg grapes and wine. The contents of most of the monoterpenes (free and glycosylated forms) in the grapes and wine increased in response to MeJA. An analysis of the expression of the genes in the terpenoid biosynthesis pathway indicated that the related biosynthetic pathways were activated by MeJA. The transcript levels of some genes were consistent with monoterpene production, including VviCSLinNer, VviGwbOciF, VviPNRLin, VviGT14 and VviUGT85A1L1. The developmental expression patterns of the VviPP2B1 and VviMYB24 transcription factor genes were positively correlated with monoterpene accumulation in ripening grapes. CONCLUSIONS: Our results suggest that MeJA may be useful for improving the aroma quality of grapes and wines. [ABSTRACT FROM AUTHOR]

Submerged macrophytes are regarded as being hardly assimilated by zooplankton for their lack of essential nutrients such as polyunsaturated fatty acids (PUFAs) thus serve as poor quality food, contrary to field stable isotopic investigations with observed macrophyte carbon contributions to zooplankton. However, periphyton growing on them produces the PUFAs and is thus a nutrient supplement. We hypothesize that with this supplement, zooplankton can be supported by macrophyte carbon. To test this hypothesis, we fed zooplankton with (1) 13C enriched Vallisneria natans detritus, (2) periphyton and (3) a mix of the two. We compared growth and reproduction of zooplankton under these three food treatments and calculated zooplankton assimilation of macrophyte carbon when fed a mixed diet, using a stable isotope-mixing model. The fatty acid profile of the two carbon resources was also analyzed. Our results demonstrate that Daphnia magna can grow and reproduce well, and use V. natans carbon when a supplement of periphyton is available. [ABSTRACT FROM AUTHOR]

The purpose of this study was to analyze the α-SiO2 content, composition, dispersion, morphology, and free radical content of dust between the alveolar and the workplace, to explore the possible changes in the properties (especially the pathogenicity) of dust after it enters the lung. We collected the dust in the workplace in HANDAN Coal mine. They were selected by a 400 mesh sieve and was made a suspension of 50 mg/ml, which would be used to perfuse into the trachea of rats. When one week, four weeks, eight weeks, fourteen weeks, twenty weeks after perfusing, we harvested dust in rats alveolar through lung lavage for further processing. In the animal test, typical fibrous nodules appeared 20 weeks after dust exposure. No inflammatory reaction was observed in the saline group. The results of animal experiments showed that there was no significant difference in the content of α-SiO2 between dust in the workplace and the lung lavage (P > 0.05). The content of the Fe element gradually increased with dust exposure time. The 12 elements of Al, Mg, Si, Pb, Mn, Ni, Zn, Cu, Cr, Sb, Cd, and AS were reduced in the experiment group compared with the workplace group. The shape of the dust in the workplace was mostly spherical. The shape of the dust extracted from the lung lavage fluid was mostly blocky and angular, and a few dust edges were sharp, and more than 80% of the particle size was smaller than 5 μm, while less than 1% of the particle size was larger than 10 μm. The amount of hydroxyl radical released by lung lavage dust in phosphate buffer was higher than that of the workplace dust. After the dust entered the alveoli, the content of α-SiO2 in the dust did not change with dust exposure time, while the content of elements in the dust, the morphology, and dispersion of the dust changed. The ability of dust in alveoli to produce hydroxyl radicals in phosphate buffer was higher than that in the workplace. [ABSTRACT FROM AUTHOR]

Summary: Radio frequency (RF) treatment at 27.12 MHz was employed to inactivate the anti‐nutritional factors (ANFs), including lipoxygenase (LOX), urease and trypsin inhibitor to minimise deleterious effects caused by conventional hot‐air heating. The effects of RF heating on the ANF activities, physicochemical properties and processing quality of intact soybean were investigated. The results revealed that ANF activities were effectively inactivated within 300 s by RF heating and inactivation rates of LOX, urease and trypsin inhibitor were 95.2% (270 s), 93.4% (285 s) and 89.4% (300 s), respectively. In addition, RF heating improved physicochemical properties and processing quality of soybean products when the trypsin inhibitor was inactivated. On the contrast, conventional thermal treatment significantly decreased functional properties and led to the formation of greater aggregates. Our results may provide a novel method to inactivate endogenous enzyme in crops without negative impact on processing quality. [ABSTRACT FROM AUTHOR]

Summary: The fast growth, ease of metabolic labelling and potential for feedstock and biofuels production make duckweeds not only an attractive model system for understanding plant biology, but also a potential future crop. However, current duckweed research is constrained by the lack of efficient genetic manipulation tools. Here, we report a case study on genome editing in a duckweed species, Lemna aequinoctialis, using a fast and efficient transformation and CRISPR/Cas9 tool. By optimizing currently available transformation protocols, we reduced the duration time of Agrobacterium‐mediated transformation to 5–6 weeks with a success rate of over 94%. Based on the optimized transformation protocol, we generated 15 (14.3% success rate) biallelic LaPDS mutants that showed albino phenotype using a CRISPR/Cas9 system. Investigations on CRISPR/Cas9‐mediated mutation spectrum among mutated L. aequinoctialis showed that most of mutations were short insertions and deletions. This study presents the first example of CRISPR/Cas9‐mediated genome editing in duckweeds, which will open new research avenues in using duckweeds for both basic and applied research. [ABSTRACT FROM AUTHOR]

The dysfunction of the hypothalamus–pituitary–adrenal (HPA) axis is often seen in Alzheimer's disease (AD) patients with cognitive deficits. Selective inhibition of phosphodiesterase (PDE) 4 and 5 has already proven to be effective in reducing beta-amyloid 1–42 (Aβ1–42)-mediated pathology by regulating corticotropin-releasing factor (CRF) and glucocorticoid receptor (GR) expression, suggesting that PDE-dependent signaling is involved in Aβ1–42-induced HPA axis dysfunction. However, nausea and vomiting are the side effects of some PDE4 inhibitors, which turn our attention to other PDEs. PDE2 are highly expressed in the hippocampus and cortex, which associate with learning and memory, but not in the area postrema that would cause vomiting. The present study suggested that microinjection of Aβ1–42 to the intracerebroventricle induced learning and memory impairments and dysregulation of the HPA axis by increased expression of CRF and GR. However, the PDE2 inhibitor Bay 60-7550 significantly ameliorated the learning and memory impairment in the Morris water maze (MWM) and step-down passive avoidance tests. The Aβ1–42-induced increased CRF and GR levels were also reversed by the treatment with Bay 60-7550. These Bay 60-7550's effects were prevented by pretreatment with the PKG inhibitor KT5823. Moreover, the Bay 60-7550-induced downstream phosphorylation of cyclic AMP response element binding (pCREB) and brain-derived neurotrophic factor (BDNF) expression was also prevented (or partially prevented) by KT5823 or the PKA inhibitor H89. These results may lead to the discovery of novel strategies for the treatment of age-related cognitive disorders, such as AD, which affects approximately 44 million people worldwide. [ABSTRACT FROM AUTHOR]

Terrestrial carbon resources are generally regarded as inferior‐quality food for zooplankton due to a lack of essential biomolecules (e.g., polyunsaturated fatty acids). However, recent stable isotopic studies have suggested terrestrial carbon to be substantial resource for zooplankton, though the mechanisms of assimilation are not well understood. Here, we consider the possibility that heterotrophic microbes can upgrade the nutritional value of terrestrial carbon and thereby support the somatic growth and reproduction of zooplankton. To test this hypothesis, a simplified experimental food chain was established. Aquatic microbes were raised under dark laboratory conditions on a terrestrial carbon source, decaying corn straw (Zea mays L.), and the resulting degradation products were supplied as food to Daphnia magna. Significant increases in microbial abundance and concomitant increases in polyunsaturated fatty acid were observed during the degradation of corn straw. Furthermore, experiments indicated that the somatic growth and reproduction of D. magna was supported exclusively by the products of corn straw decay. Our results indicate a pathway for the assimilation of terrestrial carbon by zooplankton, in which heterotrophic microbes serve as trophic links. [ABSTRACT FROM AUTHOR]

Copyright of Knowledge & Management of Aquatic Ecosystems is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Knowledge & Management of Aquatic Ecosystems is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Polyunsaturated fatty acids are oxidised to generate beany flavour under catalysis of lipoxygenase (LOX). Using conventional thermal treatment to inactivate LOX lead to a serious nutritional and functional loss in soybean products due to the prolonged exposure to the high‐temperature environment. Radio frequency (RF) is a different type of heating technology that sample is heated inside and outside at the same time with deep penetration. RF treatment was proposed to process soybean to rapidly inactivate LOX while remaining the quality and functional properties of soybean product. The results showed that the inactivation rate of LOX subjected to RF treatment for 210 s was 94.30%, as compared with 3.08% under conventional thermal treatment (110 °C) for the same duration. Functional properties of soybean protein isolate (SPI) after RF treatment were much higher than that of SPI with conventional thermal treatment. Analysis of the volatile compounds of soy milk indicated that the relative concentration of hexanal decreased from 521 to 116 μg L−1 and that of 1‐hexanol decreased from 271 to 6.99 μg L−1. Therefore, RF treatment could better improve the sensory properties of soy milk. This study mainly indicated the difference in inactivation rate of lipoxygenase of intact soybean by comparing two approaches (RF treatment and conventional thermal treatment). After that, we evaluated the shifts in the functional properties of soybean protein isolates under previous methods and the changes in the quality associated with lipoxygenase. [ABSTRACT FROM AUTHOR]

Summary: Radio frequency (RF) preprocessing combined with pulsed electric field (PEF) processing was employed to inactivate polyphenol oxidase (PPO) in apple juice. PPO enzyme levels, loss of total phenolic content (TPC), colours and volatile components in the apple juice were subsequently determined and compared with conventional processing methods (60 °C for 10 min and 70 °C for 10 min). Results indicated that, when the apple tissue was preprocessed using RF for 10 min, the residual activity of PPO decreased to 13.57%; when the squeezed juice was processed by PEF, the residual activity decreased to about 5% at 15–35 kV cm−1 for 400 μs. RF treatment caused no significant loss in TPC. Compared with the conventionally processed samples, the apple juice that was RF‐treated for 10 min and PEF‐treated at 15 kV cm−1 for 400 μs increased its lightness and maintained its fresh‐like flavour. [ABSTRACT FROM AUTHOR]

The magnetic properties and microstructures of a quaternary Pr–Co–Ti–C alloy were investigated. After heat treating at 800 °C, the quaternary alloy developed high coercivity (16.7 kOe) and high energy product (8.6 MGOe). Hysteretic loop shapes exhibiting single-phase magnetic character were achieved which was a problem which previously plagued development of Pr–Co alloys. The optimum microstructure contained 75–100 nm Pr[sub 1]Co[sub 5] hard magnetic grains, 75–100 nm Pr[sub 1]Co[sub 2] second phases, and <10 nm TiC grain boundary precipitates. The important factors in achieving optimum loop shapes in Pr–Co alloys were examined in detail. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Detailed knowledge of micromechanics of individual particle collisions with the presence of liquid is crucial for modelling/understanding of wet granular flows that are omnipresent in nature and industrial applications. Despite many reported studies, very limited detailed interface-resolved modeling of such collision problems has been conducted. This article presents an improved model for direct numerical simulations of normal impacts of spheres on wet surfaces. This model combines the immersed boundary method and the volume-of-fluid method supplemented with a model describing gas-liquid-solid contact line. It is demonstrated that our model not only correctly describes the collision dynamics of wet particles, but also well captures the dynamics of the liquid bridge formed during the collision. Quantitative agreement is obtained between the simulation results and the experimental data. It is concluded that the developed model constitutes a powerful tool to complement experimental studies, which are challenging for more complex wet collision systems in practice. © 2017 American Institute of Chemical Engineers AIChE J, 2017 [ABSTRACT FROM AUTHOR]

Biomanipulation via fish regulation combined with submerged plant introduction is an effective measure to restore eutrophic shallow lakes. Improved water quality and clarity promote growth of benthic algae, which with submerged plants may limit sediment phosphorus (P) release, thereby reinforce lake recovery. Our study sought to evaluate the effect of such a biomanipulation on water quality, benthic algal development and sediment P release in a shallow, tropical lake by (1) comparing porewater and lake water quality, light intensity and benthic algal development in restored and unrestored sections; (2) conducting a P radiotracer experiment to track P release from sediment cores sampled from both sections. The biomanipulation led to lower total P, total dissolved P, and soluble reactive P concentrations in lake water, lower phytoplankton biomass, and increased light intensity at sediment surface, stimulating benthic algal development. Moreover, sediment P release was lower in the restored than unrestored section. Concurrently, dissolved oxygen levels in upper layers of the sediment cores were higher in the restored section. Our study indicates that the biomanipulation improved water quality and enhanced growth of benthic algae, thereby reducing sediment P release, which may be one of the main mechanisms to create successful restoration. [ABSTRACT FROM AUTHOR]

The mutual effects between food components and packaging materials under high-pressure processing was investigated. Pouches made of Polyethylene terephthalate/Polyethylene and Polyamide/Polyethylene packaging olive oil and glycerol trioleate were subjected to different pressures and holding times, and then stored at 23 ± 2oC for 40 days. The results proved that there were significant effect between lipid and packaging under high-pressure processing treatment. High pressure would be beneficial to extend food shelf life and affect the enthalpy of fusion of packaging materials, especially when making contact with olive oil which probably acted as a plasticizer to change the polymer structure. [ABSTRACT FROM AUTHOR]

Direct numerical simulation results for gas flow through dynamic suspensions of spherical particles is reported. The simulations are performed using an immersed boundary method, with careful correction for the grid resolution effect. The flow systems we have studied vary with mean flow Reynolds number, solids volume fraction, as well as particle/gas density ratio. On the basis of the simulation results, the effect of particle mobility on the gas-solid drag force is analyzed and introduced into the existing drag correlation that was derived from simulations of stationary particles. This mobility effect is characterized by the granular temperature, which is a result of the particle velocity fluctuation. The modified drag correlation is considered so-far the most accurate expression for the interphase momentum exchange in computational fluid dynamics models, in which the gas-solid interactions are not directly resolved. © 2016 American Institute of Chemical Engineers AIChE J, 62: 1958-1969, 2016 [ABSTRACT FROM AUTHOR]

Pulsed electric fields (PEF) processing is a promising nonthermal food preservation technology, which is ongoing from laboratory and pilot plant scale level to the industrial level. Application of PEF processing may be a good alternative treatment to thermal methods in protein-based foods. A large number of literatures have fully demonstrated that small molecule compounds in plant-based foods, mainly aroma compounds and health-related phytochemicals, were not significantly affected by PEF. However, there was a lack of knowledge on the effects of PEF on proteins and qualities of protein-based foods. This review focuses on effects of PEF processing on endogenous enzymes, safety, and quality of protein-based foods. Finally, the ways to achieve food quality assurance and food safety in PEF processing of protein-based foods are proposed. [ABSTRACT FROM AUTHOR]

Time-temperature indicators (TTIs) are devices with a time-temperature-dependent change to reflect food quality status and temperature history. There is increasing interest in the application of TTIs to monitor food cold chain logistics for food safety and quality. In this paper, a new enzymatic TTI based on enzyme reaction, diffusion and enzyme demobilization technology is developed. The mathematical model of TTI is drawn up, which shows the relationships between the changes of time and temperature and the diffusion length of the indicator's colour changed. To assess the reliability of TTI as the quality indicating device for perishable foods in the process of storage and transportation, fresh milk is studied as an example. Through the research of dynamic characteristics of milk and TTIs, five different TTIs that matched with the activation energy of the prototype milk were designed and tested in several constant temperature profiles and a variable temperature profile. By comparing the end response value of the prototype TTI with the effect of forecasting the shelf life of milk, it was considered that the enzyme reaction-diffusion TTI has good stability and reliability at dynamic storage conditions and could be used to monitor the shelf life of perishable food during the cold chain transportation. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We have investigated the possibility of forming a silver-sheathed 1212-type high-critical-temperature superconductor (HTS) with the same type of grain colony microstructure (GCM) that develops in the silver-sheathed Bi-2223 (Ag/Bi-2223) composite conductor. The basis for this study is that a silver-sheathed 1212-type superconductor having a GCM should exhibit 1) good long-length transport critical current properties, 2) better in-field performance than Ag/Bi-2223 due to the significantly shorter blocking layer distance in 1212-type as opposed to 2223-type HTS phases, and 3) long-length transport current capacity equaling or exceeding that of Ag/Bi-2223 in present-day applications. Three series of M[sub 1]Sr[sub 2]Y[sub 1-x]Ca[sub X]Cu[sub 2]O[sub z] (M-1212) compositions with M = (Bi,Pb), (Cd,Pb), and (Fe,Pb) were prepared in silver-sheathed/flat wire form by the powder-in-tube method. For M = (Bi,Pb), we were able to obtain over 80% conversion to a 1212-phase in a relatively short time (6 h) for oxygen partial pressures in the range from 0.08 to 0.21 atm and temperatures from 900 °C to 940 °C. The (Bi,Pb)-1212 phase grew with a GCM that had the same type of fiber texture found in Ag/Bi-2223 composites. However, within the range of processing conditions tolerated by a silver sheath, no transport critical current was achieved in any of the Ag/(Bi,Pb)-1212 specimens, including ones that showed the presence of an HTS phase. Various oxygen doping treatments performed at very high (ca. 88 atm O[sub 2]), intermediate (1 atm O[sub 2]), and low oxygen partial pressures (0.01 atm [sub 2]) failed to induce a global HTS phase that carried a transport current. The preponderance of evidence from these studies indicated that any superconductivity detected in Ag/(Bi,Pb)-1212 specimens was most likely due to trace amounts of either Bi-2201 or Bi-2212. For M = (Cd,Pb) and (Fe,Pb), M-1212 phases in appreciable quantity did form in the silver-sheathed composites after... [ABSTRACT FROM AUTHOR]

The influence of filter-feeding bivalves on plankton communities, nutrients, and water quality in a given aquatic ecosystem is so profound that they can be considered ecosystem engineers. In a 70-day mesocosm experiment, we tested the hypothesis that Corbicula fluminea would change plankton community structure by reducing small zooplankton and large phytoplankton and improve water quality by reducing nutrients. We monitored levels of nitrogen and phosphorus, organic suspended solids (OSS), and light at the sediment surface. Within the plankton, phytoplankton biomass (as Chl a, >0.45 μm), the biomass of microphytoplankton (>20 μm), nanophytoplankton (2–20 μm), picophytoplankton (0.2–2 μm), and zooplankton were determined. Compared with the controls, C. fluminea reduced the abundance of rotifers and the biomass of phytoplankton, and picophytoplankton, thereby modifying the plankton community structure. We did not observe reductions in TN and TP concentration, but OSS concentrations were reduced, and light intensity at the sediment surface was increased as a result of the improved water transparency. Our research shows that colonization by C. fluminea may modify plankton community structure and improve water quality of eutrophic shallow lakes, shedding further light on the ecological roles of filter-feeding bivalves in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Radio frequency (RF) processing was proposed to inactivate polyphenol oxidase (PPO) in apple tissue for improved juice quality. PPO in apple tissue exists as membrane‐bound PPO (mPPO) and soluble PPO (sPPO); mPPO is bound in chloroplast membranes and separated from phenolic substrates, preventing catalytic reaction, whereas sPPO is soluble in lumen. When cells break down, mPPO is released and comes in contact with phenolic substrates, contributing to browning and discoloration in juice. Research indicates that after RF treatment, inactivation of mPPO and sPPO in apple tissue was easier to achieve than extracted PPO. In addition, mPPO exhibited a lower thermal stability than that of sPPO. Treatment with RF for 10 min in apple tissue could effectively inactivate PPO and maintain a higher quality of squeezed apple juice than that of freshly squeezed juice treated by conventional thermal methods (65 °C for 10 min and 75 °C for 10 min). Practical applications: In fruit and vegetable processing industry, enzymatic browning is a difficult issue that leads to the deterioration of product quality. RF treatment can inactivate PPO rapidly in food and agricultural products to inhibit browning without heat conduction and overheated food surfaces, keeping high quality of the products. Results in this study could provide references for the application of RF technology on fruit and vegetable processing industry to inactivate endogenous enzyme. [ABSTRACT FROM AUTHOR]

Sodium alginate (SA) bio‐based films with gelatin (G0) and Tween 80 (T) as emulsifiers for controlled release of cinnamon essential oils (CEOs) were fabricated via mechanical stirring emulsifying–blending technique (MB) and homogenized emulsifying‐blending technique (HB). Morphology results depicted distinct microstructures of MB‐prepared film (MBF) with symmetric porous oil‐rich cross‐sections, whereas HB‐prepared film (HBF) with asymmetric cross‐section consisted of compact polymer‐rich phase on top side (A) and porous oil‐rich phase on bottom side (B). The mechanical properties of HBF were significantly superior compared with MBF (p < .05). The diffusion coefficient (D) representing the release rate of CEO presented no significant difference between CEO releasing through A and B of MBF, whereas D of CEO releasing through A of HBF was significantly smaller than through B of HBF and A of MBF (p < .05). Moreover, D of CEO releasing through A of HBF decreased significantly with the increase in SA content (p < .05). Practical applications: The blending technique‐controlled distinct structured films could be potentially applied as controlled release food packaging protecting the food inside. Sodium alginate content could also be potentially applied as control factor for controlled release food packaging protecting the food inside. [ABSTRACT FROM AUTHOR]