Efficiency of Pleurotus florida Laccase on Decolorization and Detoxification of the Reactive Dye Remazol Brilliant Blue R (RBBR) under Optimized Conditions

Laccase from the white‐rot fungus Pleurotus florida, produced under solid‐state fermentation conditions, was used for the decolorization of reactive dye Remazol Brilliant Blue R (RBBR). RBBR was decolorized up to 46% by P. florida laccase alone in 10 min. In the presence of N‐hydroxybenzotriazole (HBT), the rate of decolorization was enhanced 1.56‐fold. Central composite design of response surface methodology with four variables namely, dye, enzyme, redox mediator concentrations, and time at five levels was applied to optimize the RBBR decolorization. The predicted optimum level of variables for maximum RBBR decolorization (87%) was found to be 52.90 mg L^?1 (RBBR), 1.87 U mL^?1 (laccase), 0.85 mM (HBT), and 7.17 min (time), respectively. The validation results showed that the experimental value of RBBR decolorization (82%) was close to the predicted one. The disappearance of C–N and C–X groups, and a small shift in N–H groups in Fourier‐transform infra red (FTIR) spectroscopy confirms the degradation of RBBR chromophore by laccase enzyme. The phytotoxicity of RBBR was considerably reduced after the treatment with laccase. RBBR decolorization kinetics; K_m and V_max were calculated to be 145.82 mg L^?1 and 24.86 mg L^?1 min, respectively.     

Asteroseismology of degenerate stars

An overview of the observational and theoretical study of white dwarf pulsators is given. Particular attention is drawn to the contributions of South African-based workers.     

试论我省覆盖区区域地球化学调查

本文主要论述了覆盖区进行125万多目标区域地球化学调查的特点及其基本工作方法技术,并从我省覆盖区区域地球化学调查工作的现状出发,提出下步工作的设想.     

斑节对虾虾苗白斑综合症杆状病毒的检测和养殖跟踪

利用 2步 PCR检测技术对湛江和阳西地区的虾苗进行白斑综合病杆状病毒 ( WSSV)检测。在仔虾 2日龄最早检测到病毒 ,有 2 5%的虾苗带有 WSSV病毒。带病毒虾苗和不带病毒虾苗分别在不同养殖模式的养殖过程中跟踪。前者在湛江湖光镇普通虾塘跟踪养殖 ,它们在变化的环境中容易发病 ,p H、盐度和温度是重要的诱发因子 ,在养殖 50～ 60 d时发病死亡 ;后者在高位池和普通池养殖跟踪 ,它们对变化的环境有较大的适应性 ,养殖时间为 80～ 1 1 0 d,在相对优良的养殖技术条件下大部分可望养殖成功。环境中有 WSSV病原传入 ,不带病毒虾苗在养殖后期可以带有 WSSV病毒 ,出现白斑虾。跟踪的普通池有爆发病害 ,但是时间延后 ,跟踪的高位池没有爆发病害。     

Evaluation of two WAM white capping parameterizations using parallel unstructured SWAN with application to the Northern Gulf of Mexico, USA

The performance of two well accepted formulations for white capping and wind input of third generation wave models, viz., WAM-3 and WAM-4, were investigated using parallel unstructured SWAN (PunSWAN). Several alternative formulations were also considered to evaluate the effects of higher order steepness and wave number terms in white capping formulations. Distinct model configurations were calibrated and validated against available in situ measurements from the Gulf of Mexico. The results showed that some of the in situ calibrated models outperform the saturation level calibrated models in reproducing the idealized wave growth curves. The simulation results also revealed that increasing the power of the steepness term can enhance the accuracy of significant wave height (H_s), at the expense of a higher bias for large waves. It also has negative effects on mean wave period (T_a) and peak wave period (T_p). It is also demonstrated that the use of the quadratic wave number term in the WAM-3 formulation, instead of the existing linear term, ameliorates the T_a underestimation; however, it results in the model being unable to reach any saturation level. In addition, unlike H_s and T_p, it has been shown that T_a is sensitive to the use of the higher order WAM-4 formulation, and the bias is decreased over a wide range of wave periods. However, it also increases the scatter index (SI) of simulated T_a. It is concluded that the use of the WAM-4 wind input formulation in conjunction with the WAM-3 dissipation form, is the most successful case in reproducing idealized wave growth curves while avoiding T_a underestimation of WAM-3 and a potential spurious bimodal spectrum of WAM-4; consequently, this designates another perspective to improve the overall performance of third generation wave models.     

Gamma-ray astrophysics: parsecs to megaparsecs

A rapidly spinning, slowly accreting magnetic white dwarf (or X-ray pulsar) in hibernation is expected to result in rapid spindown as a result of the stretching and reconnection of magnetic field lines, leading to particle acceleration at the magnetospheric radiusoutside the corotation radius, and the propeller type ejection of magnetized synchrotron-emitting clouds. This may explain the non-thermal (radio and-rays) emission seen from the unique nearby AE Aquarii. Moving to Galactic distances we show how TeV-ray observations of pulsar-driven supernova remnants (with well-measured synchrotron X-ray spectra) allow us to obtain a direct measurement of the average magnetic field strength in the nebula. Finally, GeV to TeV observations of-ray blazars out to redshifts of 2 allow us to probe the intergalactic infrared radiation field, the Hubble constant and possibly the parameter of the Universe.     

A late-glacial transition from Picea glauca to Picea mariana in southern New England

Picea is an important taxon in late-glacial pollen records from eastern North America, but little is known about which species of Picea were present. We apply a recently developed palynological method for discriminating the three Picea species in eastern North America to three records from New England. Picea glauca was dominant at  14,500–14,000 cal yr BP, followed by a transition to Picea mariana between  14,000 and 13,500 cal yr BP. Comparison of the pollen data with hydrogen isotope data shows clearly that this transition began before the beginning of the Younger Dryas Chronozone. The ecological changes of the late-glacial interval were not a simple oscillation in the position of a single species' range, but rather major changes in vegetation structure and composition occurring during an interval of variations in several environmental factors, including climate, edaphic conditions, and atmospheric CO₂ levels.     

南羌塘帕度错-昂达尔错地区中生代地层含油气条件分析

南羌塘帕度错-昂达尔错地区,是羌塘盆地内最具油气资源潜力的地区之一.区内发育了从上三叠统日干配错群-上侏罗统索瓦组海相中生代地层,该套地层具备了良好的生油条件、储集条件、盖层条件,通过对其生、储、盖组合特征的分析研究,划分出3套完整的生储盖组合,并确定了帕度错-昂达尔错油气远景区.     

微拟球藻原生质体制备与再生

综合考虑酶混合液处理时间和初始细胞密度两个因素,选取终浓度为4%半纤维素酶和2%崩溃酶的酶混合液对一株海洋经济微藻——微拟球藻(Nannochloropsis oculata)进行原生质体的制备与再生,Calcofluor White染料染色可在荧光显微镜下观察到完整的原生质体细胞。实验结果表明:同一初始密度藻细胞酶处理1～3 h制备率较高;酶处理相同时间较高初始密度(2×107～3×107cells/mL)的藻细胞制备率较高,并且原生质体在再生培养基上可再生,生长趋势与野生型细胞一致。考虑到酶处理时间过长或者密度过大会对原生质体的再生产生影响,本实验选择最适酶处理时间为1h,初始细胞密度为2×107cells/mL。     

实验感染白斑杆状病毒(WSBV)的斑节对虾血液病理学研究

用光镜观察经人工感染白斑杆状病毒 (White Spot Baculovirus,WSBV) 后患典型白斑病的斑节对虾 Penaeus monodon 的血淋巴涂片,研究了WSBV导致的淋巴细胞数量及结构异常;通过检测感染WSBV后患病虾与健康虾的血清主要生化指标,首次揭示了两者的主要差异及WSBV在宿主体内增殖的时间过程.结果表明:患病虾淋巴细胞明显减少,无颗粒细胞难以找到,颗粒细胞和小颗粒细胞分别为健康虾的11.7%和4%;颗粒细胞内出现深染区、空白区或异样突起.血涂片上偶尔发现有大型固定性吞噬细胞.在患病虾血清主要生化指标中,Ca2+含量比健康虾显著升高,患病虾为15.93mmol·L-1,健康虾为10.71mmol·L-1;相反,患病虾血清中总蛋白(Tp)、总磷(PB)及乳酸脱氢酶(LDH)均比健康虾个体低,3者含量依次为:52.07g·L-1,0.34mmol·L-1和35.27IU·L-1,在健康虾个体血清中为:66.29g·L-1,0.66mmol·L-1及82.36IU·L-1;而K+,Mg2+含量无显著差异.血清中Ca2+,PB及TP的含量可以作为斑节对虾感染WSBV后出现白斑病的血清生化特征.斑节对虾感染WSBV后不同时间内血清主要生化指标显示其增殖的时间顺序可能为:24h内主要进行核酸复制,24-48h主要进行囊膜蛋白质的合成,病毒从入侵宿主细胞到从细胞内释放的过程约需48h.