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In this work, a series of flower-like CuAl layered double hydroxides (LDHs) and hierarchical CuAl/carbon fiber-LDH (CuAl/CF-LDH) materials were synthesized, and these materials were used as catalysts for the degradation of ammonia nitrogen from simulated wastewater. The morphologies and structures of the materials were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy (RS), X-ray diffraction (XRD), and the Brunauer-Emmett-Teller (BET) technique. The effects of the catalyst and H2O2 loading dosages, reaction temperature, pH, Cu/Al ratio of the samples, and contact time on the degradation process were investigated by degrading ammonia nitrogen under different conditions, and the possible degradation mechanism was discussed. CuAl/CF-LDH exhibited more effectively catalytically degradation of ammonia nitrogen than others as-prepared samples, and removal efficiency reached 99.7% under the optimized conditions. The reusing capability and stability of the materials were studied. Meanwhile, the versatility of the materials was investigated by testing their performance in the absorption of azo dye, the highest removal efficiency was found to be 99.28%. The prepared materials are promising for use as effective catalysts for the degradation of ammonia nitrogen from wastewater.
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Amoníaco , Carbono , Aguas Residuales/química , Adsorción , Fibra de Carbono , Peróxido de Hidrógeno , Hidróxidos , Cinética , NitrógenoRESUMEN
OBJECTIVE: This experiment was conducted to investigate the effects of chromium picolinate (CrP) on fat deposition, genetic expression and enzymatic activity of lipid metabolism-related enzymes. METHODS: Two hundred forty one-day-old Ross broilers were randomly divided into 5 groups with 4 replicates per group and 12 Ross broiler chicks per replicate. The normal control group was fed a basal diet, and the other groups fed the same basal diet supplemented with 0.1, 0.2, 0.4, and 0.8 mg/kg CrP respectively. The experiment lasted for 21 days. RESULTS: Added CrP in the basal diet decreased the abdominal fat, had no effects on subcutaneous fat thickness and inter-muscular fat width; 0.2 mg/kg CrP significantly decreased the fatty acid synthase (FAS) enzymatic (p<0.05); acetyl-CoA carboxylase (ACC) enzymatic activity decreased in all CrP groups (p<0.05); hormone-sensitive lipase (HSL) enzymatic activity also decreased, but the change was not significant (p>0.05); 0.4 mg/kg CrP group significantly decreased the lipoprotein lipase (LPL) enzymatic activity. FAS mRNA expression increased in all experimental groups, and the LPL mRNA expression significantly increased in all experimental groups (p<0.05), but not 0.2 mg/kg CrP group. CONCLUSION: The results indicated that adding CrP in basal diet decreased the abdominal fat percentage, had no effects on subcutaneous fat thickness and inter-muscular fat width, decreased the enzymatic activity of FAS, ACC, LPL and HSL and increased the genetic expression levels of FAS and LPL.
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The ribose-binding protein (RBP) is a sugar-binding bacterial periplasmic protein whose function is associated with a large allosteric conformational change from an open to a closed conformation upon binding to ribose. The open (ligand-free) and closed (ligand-bound) forms of RBP have been found. Here we investigate the conformational motions and residue fluctuations of the RBP by analyzing the modes of motion with two coarse-grained elastic network models, the Gaussian Network Model (GNM) and Anisotropic Network Model (ANM). The calculated B-factors in both the calculated models are in good agreement with the experimentally determined B-factors in X-ray crystal structures. The slowest mode analysis by GNM shows that both forms have the same motion hinge axes around residues Ser103, Gln235, Asp264 and the two domains of both structures have similar fluctuation range. The superposition of the first three dominant modes of ANM, consisting of the rotating, bending and twisting motions of the two forms, accounts for large rearrangement of domains from the ligand-free (open) to ligand-bound (closed) conformation and thus constitutes a critical component of the RBP's functions. By analyzing cross-correlations between residue fluctuation and the difference-distance plot, it is revealed that the conformational change can be described as a rigid rotation of the two domains with respect to each other, whereas the internal structure of the two domains remains largely intact. The results directly indicate that the dominant dynamic characteristics of protein structures can be captured from their static native state using coarse-grained models.
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Proteínas de Escherichia coli/química , Modelos Moleculares , Proteínas de Unión Periplasmáticas/química , Conformación Proteica , Algoritmos , Aminoácidos/química , Aminoácidos/metabolismo , Anisotropía , Sitios de Unión , Cristalografía por Rayos X , Elasticidad , Proteínas de Escherichia coli/metabolismo , Movimiento (Física) , Proteínas de Unión Periplasmáticas/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Rotación , TermodinámicaRESUMEN
Acremonium terricola culture (ATC) has similar bioactive constituents to Cordyceps and is known for its nutrient and pharmacological value, indicating the potential of ATC as a new feed additive in dairy cow feeding. The primary aim of this experiment was to investigate the effects of increasing amounts of ATC in diets on milk performance, antioxidant capacity, and rumen fermentation, and the secondary aim was to evaluate the potential effects of high doses of ATC. A total of 60 multiparous Holstein cows (110 ± 21 days in milk; 2.53 ± 0.82 parity) were assigned into 15 blocks and randomly assigned to one of four groups: 0, 30, 60, or 300 g/d of ATC per cow for 97 days. Data were analyzed using repeated measures in the Mixed procedure. Dry-matter intake was not changed (p > 0.05), while energy-corrected milk and fat-corrected milk yields increased linearly and quadratically, and somatic cell count in milk decreased linearly and quadratically (p < 0.05). The lactation efficiency and the yields of milk fat and protein increased linearly (p < 0.05). On day 90, serum catalase level, total oxidative capacity, glutathione peroxidase, immunoglobulin A, and immunoglobulin M concentrations were significantly higher in the 60 and 300 g/d groups than in the 0 g/d group (p < 0.05). ATC addition showed linear effects on total volatile fatty acid (VFA), acetate, branched VFA concentrations, and rumen pH (p < 0.05). Supplementing 60 and 300 g/d ATC significantly affected the bacterial composition (p < 0.05). The relative abundance of Christensenellaceae_R-7_group and Lachnospiraceae_NK3A20_group were significantly increased by 60 g/d supplementation, and the relative abundance of Erysipelotrichaceae_UCG_002, Acetitomaculum, Olsenella, and Syntrophococcus were significantly increased by 300 g/d supplementation (p < 0.05). ATC was effective in enhancing rumen fermentation and reducing somatic cell count in milk, thereby improving milk yield. The optimized dose of ATC was 60 g/d for lactating cows, and there were no risks associated with high doses of ATC.
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OBJECTIVE: To compare the efficacy and safety of tranexamic acid (TA) and norethisterone (NET) for the treatment of patients with ovulatory menorrhagia in China. METHODS: One hundred and thirty one patients with proven ovulatory menorrhagia from gynecologic clinics of 5 teaching hospitals located in 4 different cities in China were enrolled during Jul 2004 to Dec 2006. Among them 128 completed the study. Patients were randomly divided into two therapeutic regimen groups: TA 1 g thrice daily during menstrual cycle days (D) 1-5, 69 cases; or NET 5 mg twice daily on D19-26, 59 cases. The drugs were administered for 2 consecutive cycles, then withdrawn and patients were followed-up for 1 more cycle. Data on menstrual blood loss [estimated by pictorial blood assessment chart (PBAC)], length of menstrual periods, quality of life (QOL) evaluated by a 6 item health-related questionnaire were collected before, during each cycle and were compared. RESULTS: Both treatments led to significant decreases of mean PBAC scores and shorter duration of menstrual periods, and improved the QOL ranking during the two treatment cycles. The mean percentages of PBAC decrements in the TA first and second cycles were significantly greater than those in the NET corresponding cycles(35% vs 17% , P = 0.004; 44% vs 34%, P = 0.04 respectively). The success rate of TA second cycle was higher than that of the NET second cycle (41% vs 24%, P = 0.04). Improvement of QOL ranking in the TA first cycle was also significantly better than those in the NET first cycle (P = 0.03). The percentage of patients with at least 1 adverse event in TA group (19%) was significantly lower than that in NET group (35%, P = 0.04). Patients' willingness to continue the treatment in the TA second and follow-up cycles (94%, 79% respectively) were significantly higher than those in the corresponding cycles of NET groups (79%, 59% respectively; P = 0.01, P = 0.02). CONCLUSION: The regimen of TA 3 g daily during menstrual days 1-5 is a more effective and tolerable treatment than luteal phase norethisterone for patients with ovulatory menorrhagia.
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Antifibrinolíticos/uso terapéutico , Menorragia/tratamiento farmacológico , Menstruación/efectos de los fármacos , Noretindrona/uso terapéutico , Ácido Tranexámico/uso terapéutico , Administración Oral , Adulto , Antifibrinolíticos/farmacología , Femenino , Humanos , Persona de Mediana Edad , Noretindrona/efectos adversos , Noretindrona/farmacología , Estudios Prospectivos , Calidad de Vida , Ácido Tranexámico/efectos adversos , Ácido Tranexámico/farmacología , Resultado del TratamientoRESUMEN
Adsorption is recognized as one of the most efficient approaches for antibiotics removal from water. Inspired by the enzyme-substrate interaction model, we proposed induced-fit adsorption (IFA) model, and rationally designed and fabricated diol-based porous organic polymers (POPs) as adsorbents for tetracycline (TC) removal. For 2,3-naphthalenediol-based POP (NTdiol-POP), the preferable geometry of diol-groups contributed to the high binding energy with TC species and flexible methylene linkages between neighboring rigid naphthalene rings gave rise to precisely matching between TC species and adsorbents, that is, the induced-fit conformation change. As a result, NTdiol-POP exhibited a high saturated adsorption capacity of 155.8â¯mgâ¯g-1. More importantly, NTdiol-POP exhibited excellent TC removal efficiencies in both concentrated solution (96% for 4 p.p.m) and trace level solution (97% for 250 p.p.b).
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Glicoles/química , Polímeros/química , Tetraciclina/química , Tetraciclina/aislamiento & purificación , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Porosidad , Agua/químicaRESUMEN
OBJECTIVE: To study the effect of O/W Microemulsion in enhancing solubility of baicalin and puerarin. METHOD: The Pseudo-ternary phase diagram was employed to selected the formulations of O/W microemulsion. The partical size of microemulsion, and solubility of baicalin and puerarin in water, oil phase, surfactant, microemulsion and alcohol were determined, respectively. RESULT: 11 types of microemulsion formulations have the effect in enhancing the solubility of baicalin and puerarin; the solubility of Baicalin in microemulsion is higher as 5-15 times than it in water, the solubility of Puerarin in microemulsion is higher as 3 - 4 times than it in water. CONCLUSION: Microemulsion is good in enhancing solubility of effective compounds extracted from Chinese medical herbs.