RESUMEN
Denitrification and anaerobic ammonium oxidation (anammox) are key processes for nitrogen removal in aquaculture, reducing the accumulated nitrogen nutrients to nitrogen gas or nitrous oxide gas. Complete removal of nitrogen from aquaculture systems is an important measure to solve environmental pollution. In order to evaluate the nitrogen removal potential of marine aquaculture ponds, this study investigated the denitrification and anammox rates, the flux of nitrous oxide (N2O) at the water-air interface, the sediment microbial community structure, and the gene expression associated with the nitrogen removal process in integrated multi-trophic aquaculture (IMTA) ponds (Apostistius japonicus-Penaeus japonicus-Ulva) with different culture periods. The results showed that the denitrification and anammox rates in sediments increased with the increase of cultivation periods and depth, and there was no significant difference in nitrous oxide gas flux at the water-air interface between different cultivation periods (p > 0.05). At the genus and phylum levels, the abundance of microorganisms related to nitrogen removal reactions in sediments changed significantly with the increase of cultivation period and depth, and was most significantly affected by the concentration of particulate organic nitrogen (PON) in sediments. The expression of denitrification gene (narG, nirS, nosZ) in surface sediments was significantly higher than that in deep sediments (p < 0.05), and was negatively correlated with denitrification rate. All samples had a certain anammox capacity, but no known anammox bacteria were found in the microbial diversity detection, and the expression of gene (hzsB) related to the anammox process was extremely low, which may indicate the existence of an unknown anammox bacterium. The data of this study showed that the IMTA culture pond had a certain potential for nitrogen removal, and whether it could make a contribution to reducing the pollution of culture wastewater still needed additional practice and evaluation, and also provided a theoretical basis for the nitrogen removal research of coastal mariculture ponds.
Asunto(s)
Acuicultura , Bacterias , Desnitrificación , Microbiota , Nitrógeno , Óxido Nitroso , Penaeidae , Estanques , Nitrógeno/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Estanques/microbiología , Animales , Penaeidae/microbiología , Óxido Nitroso/metabolismo , Óxido Nitroso/análisis , Sedimentos Geológicos/microbiología , Oxidación-Reducción , Compuestos de Amonio/metabolismoRESUMEN
Researchers have developed a uniform grating DFB with an integrated active optical feedback waveguide (UG-AFDFB) to enhance the modulation speed of direct modulation lasers (DMLs) while reducing costs based on identical active layer designations. However, this design has difficulties in obtaining high single mode yield (SMY) and low relative intensity noise (RIN) as a result of the strong optical feedback caused by the integrated active feedback waveguide (AFW) and the random phase of the facet phase. In this paper, a partial corrugated grating DFB with an integrated active optical feedback waveguide (PG-AFDFB) is proposed to address this issue. Comparison of SMY, S21, RIN, modulation eye pattern, and frequency chirp parameters between UG-AFDFB and PG-AFDFB based on time-domain transmission line laser mode reveals that PG-AFDFB with an optimized grating couple parameter κ performs significantly better than UG-AFDFB under the same conditions. Furthermore, the performance of PG-AFDFB is not sensitive to the random phase of the rear facet phase. Even when κ ranges from 6000 /m to 12000 /m, the current in the AFW is between 0â mA and 20â mA, and the length of the AFW ranges from 50â µm to 100â µm; the SMY of PG-AFDFB remains above 80%.
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Observational studies have shown an association between liver dysfunction and hepatocellular carcinoma (HCC), but the causality relationship between them is unclear. We aimed to determine whether there is a bidirectional causal relationship between liver function indicators (alanine aminotransferase, ALT; aspartate aminotransferase, AST; alkaline phosphatase, ALP; γ-glutamyltransferase, GGT) and HCC. Our two-sample Mendelian randomization (MR) study acquired single nucleotide polymorphisms (SNPs) associated with liver function indicators (ALT, n = 134,182; AST, n = 134,154; GGT, n = 118,309; ALP, n = 105,030) and with HCC (n = 197,611) from publicly available genome-wide association studies (GWAS) of East Asian ancestry in Japan (BioBank Japan, BBJ). Univariable MR analyses were performed to identify whether the genetic evidence of exposure was significantly associated with outcome. Multivariable MR analysis was conducted to estimate the independent effects of exposures on outcome. Univariable MR analysis indicated that the level of ALT, AST, and GGT was the risk factor for HCC incidence. Meanwhile, multivariable MR analysis revealed that AST was an independent risk factor for HCC. The hazard ratio (HR) of the probability of HCC was 3.045 [95% confidence interval (95%CI), 1.697-5.463, p = 0.003] for AST. The results of reverse MR analyses showed that gene-predictive HCC incidence could increase the levels of AST (HR = 1.031, 95%CI: 1.009-1.054, p = 2.52 × 10-4) and ALT (HR = 1.040, 95%CI: 1.019-1.063, p = 0.005). Meanwhile, HCC may be negatively correlated with ALP levels (HR = 0.971, 95%CI: 0.947-0.995, p = 0.018). This study provides evidence to support that genetically predicted higher levels of AST are related to increased risk of HCC, with no strong evidence of a causal effect of genetically predicted ALP, ALP, and GGT on HCC. In addition, genetic predisposition to HCC could influence blood concentration of ALT, AST, and ALP. Thus, this may create a vicious cycle.
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A multi-period-delayed feedback (MPDF) photonic circuit constructed by a Sagnac ring and two coupled rings was designed. By coupling a distributed feedback (DFB) laser diode (LD) with the MPDF, a narrow linewidth semiconductor laser was demonstrated. The linewidth of the DFB-LD with MPDF was narrowed to be around 2 kHz, which is reduced by three orders of magnitude, and the linewidth reduction capability could be maintained when the wavelength of the DFB-LD was tuned in a range wider than 3 nm. The laser frequency stability can also be improved using the proposed technique, and the frequency fluctuation was reduced for nearly 8 times in comparison with the DFB-LD.
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BACKGROUND: About 80% lung cancer is non-small cell lung cancer (NSCLC) and more than 70% are in advanced stage. The aim of this study is to evaluate the clinical efficacy and the side effects of erlotinib in the treatment of elderly patients with advanced non-small cell lung cancer. METHODS: Twenty-nine patients with advanced non-small cell lung cancer were treated with erlotinib 150 mg/d, then the adverse reaction and clinical efficacy were recorded during 3 months. RESULTS: Total 29 patients were evaluated for efficacy. The total rate of effect was 20.69%, including 1 case CR, 5 cases PR, 9 cases SD and 14 cases PD. We compared the effective rate of stage III with IV. There were no significant difference between the effective rate of stage III and IV (P=0.337). The main side effects were rash (37.93%), diarrhea (17.24%) and vomiting (6.9%) and most side effects were grade I and II. CONCLUSIONS: Erlotinib for elderly patients with advanced non-small cell lung cancer have better effective and less toxic effects and the further clinical study should be warranted.
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BACKGROUND: About 80% lung cancers belong to non-small cell lung cancer (NSCLC) and more than 70% are in advanced stage. The aim of this study was to evaluate the clinical efficacy and toxicity of erlotinib and GP/TP regimen on advanced non-small cell lung cancer. METHODS: Ninety-one advanced NSCLC patients with different treatments from January 2007 to April 2009 in our hospital were retrospectively analyzed. Ninety-one patients were divided into the erlotinib and TP/GP group. Erlotinib group: received erlotinib 150 mg/dl TP/GP group: the original chemotherapy for advanced non-small cell lung cancer. The cycles were repeated for 21 days. The patients were given docetaxel (80 mg/m(2), d1) or gemcitabine (1 000 mg/m(2), d1, 8) +cisplatin (70 mg/m(2), d2); then the adverse reaction and clinical efficacy were recorded during 3 months. RESULTS: Total 91 patients were evaluated for efficacy. The total rate of effect was 23.33% in erlotinib group. The side effects were erythra, diarrhea and vomiting. Pulmonary fibrosis was found in one patient after 21 days. TP/GP group: the total rate of effect was 27.78% and 28% and the side effects were bone marrow depression and reaction of gastrointestinal tract. There were no significantly difference between the two groups in the total rate of effect (P>0.05). But the side effects were less in erlotinib group, and there were significantly difference between the two groups. CONCLUSIONS: Erlotinib on advanced non-small cell lung cancer shows more effectiveness and adverse reactions are tolerable. The further clinical study should be warranted.