Biopolymer-assisted enzyme-induced carbonate precipitation for immobilizing Cu ions in aqueous solution and loess.

Wastewater, discharged in copper (Cu) mining and smelting, usually contains a large amount of Cu2+. Immobilizing Cu2+ in aqueous solution and soils is deemed crucial in preventing its migration into surrounding environments. In recent years, the enzyme-induced carbonate precipitation (EICP) has been widely applied to Cu immobilization. However, the effect of Cu2+ toxicity denatures and even inactivates the urease. In the present work, the biopolymer-assisted EICP technology was proposed. The inherent mechanism affecting Cu immobilization was explored through a series of test tube experiments and soil column tests. Results indicated that 4 g/L chitosan may not correspond to a higher immobilization efficiency because it depends as well on surrounding pH conditions. The use of Ca2+ not only played a role in further protecting urease and regulating the environmental pH but also reduced the potential for Cu2+ to migrate into nearby environments when malachite and azurite minerals are wrapped by calcite minerals. The species of carbonate precipitation that are recognized in the numerical simulation and microscopic analysis supported the above claim. On the other hand, UC1 (urease and chitosan colloid) and UC2 (urea and calcium source) grouting reduced the effect of Cu2+ toxicity by transforming the exchangeable state-Cu into the carbonate combination state-Cu. The side effect, induced by 4 g/L chitosan, promoted the copper-ammonia complex formation in the shallow ground, while the acidic environments in the deep ground prevented Cu2+ from coordinating with soil minerals. These badly degraded the immobilization efficiency. The Raman spectroscopy and XRD test results tallied with the above results. The findings shed light on the potential of applying the biopolymer-assisted EICP technology to immobilizing Cu ions in water bodies and sites.

Fluorescence "Off-On" Probe for L-Cysteine Detection Based on Nitrogen Doped Carbon Dots.

Herein, a simple and efficient fluorescence analysis method for L-Cysteine (L-Cys) was established. The method was based on the fluorescent "off-on" mode of nitrogen doped carbon dots (NCDs). The NCDs were prepared via a facile one-step solvothermal method. In the process of exploring the bio-functional application of these newly synthesized NCDs, we found these NCDs with rich functional groups exhibited excellent optical properties. In addition, these newly synthesized NCDs showed an excitation-dependent emissions photolumine-scent (PL) property and exhibited good performance in the detection of Fe3+ ions by quenching the blue emission fluorescence. Interestingly, the quenched fluorescence of NCDs was recovered with the addition of L-Cys, which provided a novel approach for L-Cys detection. The NCDs-based fluorescent "off-on" sensor has a wide linear detection range (0-100 µM), and a relatively low detection limits (0.35 µM) for L-Cys. This simple fluorescent "off-on" approach is, very sensitive and selective for L-Cys detection, which also provides a new insight on NCDs biosensor application.

Effects of pioglitazone hydrochloride and vitamin E on meat quality, antioxidant status and fatty acid profiles in finishing pigs.

To investigate the effects of pioglitazone hydrochloride (PGZ) and vitamin E (VE), 160 Duroc × Landrace × Large White pigs were randomly divided into a 2 × 2 factorial arrangement with 2 levels of PGZ (0 or 15 mg/kg) and 2 levels of VE (0 or 325 mg/kg) for 28 days. Each group had 5 replicates with 8 pigs, half males and half females. Feeding PGZ increased intramuscular fat and VE supplementation decreased cooking loss (P < 0.05). Feeding VE increased total polyunsaturated fatty acid (PUFA), C18:2n-6 and C18:3n-3 (P < 0.05). For 18:3n-3, the increase in C18:3n-3 due to VE was accentuated when combined with PGZ (P < 0.001). Additionally, VE tended to increase superoxide dismutase (P = 0.079) and glutathione peroxidase activity (P = 0.054). In summary, PGZ and VE had positive effects on pork quality by decreasing cooking loss and increasing intramuscular fat and antioxidant capacity, and may prove useful in improving the healthfulness of fatty acid profiles.

Dietary Supplementation with Pioglitazone Hydrochloride and Chromium Methionine Improves Growth Performance, Meat Quality, and Antioxidant Ability in Finishing Pigs.

This work was designed to investigate the synergistic effects of pioglitazone hydrochloride (PGZ) and chromium methionine (CrMet) on meat quality, muscle fatty acid profile, and antioxidant ability of pigs. Pigs in four groups were fed a basic diet or basic diet supplemented with 15 mg/kg of PGZ, 200 µg/kg of CrMet, or 15 mg/kg of PGZ + 200 µg/kg of CrMet. In comparison to the control group, the average daily feed intake, feed/gain ratio, and serum high-density lipoprotein level decreased in the PGZ + CrMet group. Dietary PGZ + CrMet supplementation increased carcass dressing percentage, intramuscular fat, and marbling score. The percentages of C18:1ω-9c, C18:2ω-6c, C18:3ω-3, and polyunsaturated fatty acid (PUFA) in the longissimus thoracis muscle were increased in the PGZ + CrMet group. Greater superoxide dismutase and glutathione peroxidase activities were observed in the PGZ + CrMet group compared to the control group. Collectively, these findings suggested that feed with PGZ and CrMet improved the growth performance and meat quality, especially for PUFA proportions and antioxidant ability.

Differentiation capacities of skeletal muscle satellite cells in Lantang and Landrace piglets.

We isolated and cultured satellite cells (SCs) from the longissimus dorsi muscles of 1-day-old male Landrace and Lantang piglets to compare the SC differentiation capacity in the two breeds. Lantang piglets yielded more (P < 0.05) SCs per gram of muscle than Landrace piglets (5.2 ± 0.9×104 vs. 2.4 ± 0.2×104). Transcription of the differentiation markers myogenin and myosin heavy chain I (MyHC I) in the longissimus dorsi muscle was higher in Lantang than Landrace piglets (P < 0.05). Protein levels of myogenin (P < 0.05), MyHC I (P < 0.05), and myogenic regulatory factor 4 (P = 0.07) were higher in Lantang than Landrace piglet SCs after 72 h of differentiation. Creatine kinase activity was higher in Lantang than Landrace piglet SCs after 24, 48, and 72 h of differentiation (P < 0.05), and there was a greater fusion index in Landrace piglet SCs after 72 h of differentiation. In addition, phosphorylation of Akt, mTOR, S6K1, S6, and 4EBP1 was lower in Lantang than Landrace piglet SCs (P < 0.05). Thus differentiation was more extensive in Lantang than Landrace piglet SCs, but expression of the mTOR signaling pathway was lower in Lantang piglet SCs, suggesting mTOR signaling may inhibit myogenic differentiation. These findings reveal that mTOR signaling is a factor in myogenesis and imply that mTOR could potentially serve as an activator of myoblast differentiation and muscle regeneration.

Successful outcome of an integrated strategy for the reduction of schistosomiasis transmission in an endemically complex area.

Schistosomiasis is one of the major public health problems in the People's Republic of China (and elsewhere), seriously threatening health as well as social and economic development. An integrated control strategy, emphasising transmission control but also aimed at reducing greenhouse gases, was carried out in Jiangling county, Hubei province from 2007 to 2009. Three villages were chosen for a pilot study involving removal of cattle from neighbouring, snail-infested grasslands, improving sanitation and construction of units for household biogas production in addition to routine control measures. Both prevalence and intensity of infection in the snails in the neighbourhood were greatly reduced after two years of implementation, while the prevalence of schistosomiasis in humans in the three villages had been reduced by 29%, 34% and 24%, respectively. The removal of cattle and construction of biogas production units had an additional positive effect in that the annual, average emission of greenhouse gases such as methane (CH4) and carbon dioxide (CO2) were reduced by an estimated 7.8 and 80.2 tons, respectively.