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In order to explore the spatial and temporal characteristics of the phytoplankton community structure and its influencing factors in Shanghai rivers, the water quality and phytoplankton community structure at 44 river channel sites in a central urban area, new town area, and rural area in Shanghai were investigated from September to October 2018 (autumn) and July to August 2019 (summer). The results showed that:① Chlorophyta was the dominant phyla during the autumn and summer, and was followed by Cyanobacteria and Bacillariophyta. Cyanobacteria dominated the phytoplankton community in terms of density. The number of species and density of phytoplankton were 24% and 2.77 times higher, respectively, than those during the summer and autumn. The dominance of

In order to better understand the casting process, we carried out global simulations of heat transfer to investigate the temperature distributions in furnace at 80 mm of insulation cage elevation and 40% of silicon melt solidification for multi-crystalline silicon (mc-Si) ingot using an industrial directional solidification furnace capable of producing 500 kg silicon ingot. The effect of heater position and the crystallization state of silicon melt on temperature distribution and interface shape are discussed as well to provide the essential knowledge for system optimization.

Directional Solidification System (DSS) is the commonly used casting station in the solar industry. In order to better understand the casting process, we carried out global simulations of heat transfer to investigate effect of argon gas flow on the thermal field in a directional solidification system for multi-crystalline silicon (mc-Si). The effect of argon gas flow on the global heat transfer and the melt convection are investigated. It was found that the heat transfer at the melt free surface due to the gas convection can not be neglected, though the argon gas flow contributes little to the global heat transfer at most radiative surfaces.

A new type of sound absorbing material, which was made from super strength polyurethane and mass fiber, was investigated. And the sound absorption coefficient of the material was tested by standing wave tube method. Experiment results manifested that content of glass fibers, blowing agent and thickness have great effects on the sound absorbing performance of the sample. When the content of glass fiber and blowing agent are separately 3% and 0.4%, the performance of the material reaches optimum. The noise reduction coefficient of the material is 0.6, and the sound absorption property at middle-low frequency is good.

To observe the influence of fluid resuscitation on patients suffered from myocardial injury with severe sepsis and septic shock, and to evaluate the markers of myocardial injury during fluid resuscitation.Acute physiology and chronic health evaluation II (APACHE II) score of 78 patients with severe sepsis and septic shock induced by combined injuries was 18-35. Serum cardiac troponin I (cTnI), N-terminal-ventricular natriuretic peptide precursor (NT-proBNP) and the hemodynamic parameters were recorded before, 3 days, and 5 days after treatment, and correlative analysis was conducted.Serum cTnI was increased in 62.8% (49/78) patients with severe sepsis and septic shock, and in 73.5% of patients (36/49) the increase was greater than 2-fold of the borderline value, and in 30.6% of patients (15/49) was greater than 4-fold of the borderline value. The patients with elevated serum NT-proBNP at admission accounted for 46.2% (36/78), and after fluid resuscitation treatment, patients with continuously rising value accounted for 74.4% (58/78). The serum cTnI, NT-proBNP, pulmonary arterial wedge pressure (PAWP) and cardiac index (CI) after treatment in survival group (55 cases) were obviously improved, and changes in them in non-survival group (23 cases) was not obvious. The serum cTnI (μg/L) and NT-proBNP (ng/L) levels in the non-survival group were distinctly higher than those of the survival group (cTnI 3 days: 2.09 ± 1.00 vs. 1.57 ± 0.93, 5 days: 1.78 ± 0.67 vs. 0.72 ± 0.51; NT-proBNP 3 days: 3.52 ± 0.73 vs. 3.16 ± 0.65, 5 days: 3.21 ± 0.66 vs. 2.66 ± 0.58), and CI [ml·s(-1)·m(-2)] was obviously lower than that of the survival group (3 days: 57.6 ± 6.2 vs. 68.3 ± 5.6, 5 days: 40.5 ± 4.7 vs. 80.7 ± 6.8, all P0.05). The cTnI level (μg/L) of 46 patients whose fluid resuscitation achieved the target was lower than that of the 32 cases without achieving the target (1.16 ± 0.62 vs. 1.97 ± 0.76, P0.05), and the CI [ml·s(-1)·m(-2)] was obviously increased (61.2 ± 6.4 vs. 49.3 ± 6.1, P0.05). The results suggested that whether the fluid resuscitation achieved the target or not was not related to changes in serum NT-proBNP and PAWP. A positive correlation was found between serum cTnI and NT-proBNP (r = 0.865, Y = 2.069 + 0.695X, P0.01), also between NT-proBNP and PAWP (r = 0.762, Y = 1.125 + 4.929X, P0.01), and a negative correlation was found between cTnI and CI (r = -0.891, Y = 50.623 - 6.114X, P0.01).There is an obvious myocardial injury in the patient with severe sepsis and septic shock, and fluid resuscitation can improve the myocardial injury; the serum levels of cTnI and NT-proBNP are related to the prognosis of patients, but the significance of NT-proBNP guiding the fluid resuscitation can not be ascertained.

We experimentally demonstrate a terahertz-bandwidth photonic differentiator employing a silicon-on-insulator directional coupler. The integrated waveguide coupler with two identical paralleled strip waveguides achieves a first-order differentiator when full energy coupling is met from one waveguide to another. The integrated waveguide coupler can offer different operation bandwidths by changing the length and gap of the strip waveguides. Due to the large 3 dB bandwidth of the directional coupler, we implement the first differentiator with an operation bandwidth of 1.25 THz. The performance of this photonic differentiator is tested using Gaussian-like pulses with a pulsewidth of 2.8 ps, 4 ps, 6 ps, 8 ps, and 10 ps, respectively. The differentiation processing errors and relative energy efficiency are also discussed. This silicon chip may have potential applications in integrated photonic computing circuits with sub-picosecond pulses.

To investigate the relationship between HBV DNA and hepatitis B virus large envelope protein (HBV-LP) in patients with chronic hepatitis B.Serum HBV DNA was detected by RT-PCR and the HBV-LP was detected by enzyme linked immunosorbent assay in 320 serum samples collected from patients with chronic hepatitis B.There were no significant difference between positive rate of HBV-LP and that of HBV DNA in different HBeAg patterns (P0.05). Serum HBV-LP levels were closely correlated with HBV DNA copies (r=0.949).Serum HBV-LP is a reliable serological marker that can reflect the replication of HBV.

A hybrid actively and passively mode-locking semiconductor optical amplifier fiber ring laser based on nonlinear polarization rotation was presented, where intensity modulator not only acted as modulator but also polarizer. Under the hybrid mode-locking mechanism, output pulse is with some new characters. So, a theoretical model that describes the SOA fiber ring laser was developed and system parameters effects on mode-locking pulse are discussed.