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Adjuvants are used to increase the strength, quality, and duration of the immune response of vaccines. Neutrophils are the first immune cells that arrive at the injection site and can release DNA fibers together with granular proteins, so-called neutrophil extracellular traps (NETs), to entrap microbes in a sticky matrix of extracellular chromatin and microbicidal agents. Similar extracellular structures were also released by macrophages, mast cells, and eosinophils and are now generalized as “ETs.” Here we demonstrated that Alum adjuvant stimulation led to peritoneal cells swarming and ET release in vitro. Moreover, compared to antigen stimulation alone, ET release was significantly increased after stimulation with antigen-mixed adjuvants and in a time- and dose-dependent manner. In vivo, we were able to monitor and quantify the continuous changes of the ET release in the same fish by using the small animal in vivo imaging instrument at different times during the early stages after intraperitoneal immunization. The results showed that the fluorescence signal of ETs in the peritoneum increased from 0 to 12 h after injection and then gradually decreased. The fluorescence signals came from extracellular DNA fibers, which are sensitive to DNase I and confirmed by microscopy of peritoneal fluid ex vivo. In summary, this study introduced a new method for detecting ETs in the peritoneum of fish in vivo and indicated that ET formation is involved in the immune response at the early stage after intraperitoneal immunization to vaccines.

It deals with reaching consensus multi-agent systems reaching consensus with protocol failure in the paper. A kind of link failure or not multi-agent system whose dwell time are constant is mentioned. A method based on these cases is proposed to analyze their consensus. The simple conditions with low computational complexity are proposed and the residence time is determined according to these conditions. At last, an example is given to verify the availability.

This paper was based on the corpus built by the writers on agricultural science and technology English. Through corpus-based research and statistical tools AntConc 3.2.1 and BFSU Collocator 1.0 (Beijing Foreign Studies University Collocator 1.0), this paper tried to make an analysis of the collocation and colligation of the word “soil”. The result revealed the colligation between “soil” and its collocates in agricultural academic papers, which was instructive to academic writing and the research method was a practical reference of building a corpus on agricultural science and technology English.

The electronic structures and absorption spectra for Th 4+ : PbWO 4 have been calculated using density functional theory code CASTEP with the lattice structure optimized. It is shown by calculation that the visible range absorptions of the lead vacancy contained PWO crystal can be completely quenched by the doping of Th 4+ . The quenching of the 330, 360 and 420 nm absorption bands are discussed.

Electronic structures of PbWO4 crystals containing F-type colour centres with the lattice structure optimized are studied within the framework of the fully relativistic self-consistent Dirac–Slater theory, using a numerically discrete variational (DV-Xα) method. The calculated results show that F and F+ centres have donor energy levels in the forbidden bands. Their optical transition energies are 1.84 eV and 2.21 eV, respectively, which correspond to the 680 nm and 550 nm absorption bands. It is predicted that the 680 nm and 550 nm absorption bands originate from the F and F+ centres in PbWO4 crystals.

Random numbers have great application value in the fields of secure communications, which are commonly used as secret keys to encrypt the information. To guarantee that the information is absolutely secure in the current high-speed communication, the applied random keys should possess a generation speed not less than the encrypted data rate, according to one-time pad theory found by Shannon (Shannon C E 1949 Bell.Syst.Tech.J. 28 656) Pseudo-random numbers generated by algorithm may easily reach a fast speed, but a certain periodicity makes them difficult to meet the aforementioned demand of information security. Utilizing physical stochastic phenomena can provide reliable random numbers, called physical random number generators (RNGs). However, limited by the bandwidth of the conventional physical sources such as electronic noise, frequency jitter of oscillator and quantum randomness, the traditional physical RNG has a generation speed at a level of Mb/s typically. Therefore, real-time and ultrafast physical random number generation is urgently required from the view of absolute security for high-speed communication today. With the advent of wideband photonic entropy sources, in recent years lots of schemes for high-speed random number generation are proposed. Among them, chaotic laser has received great attention due to its ultra-wide bandwidth and large random fluctuation of intensity. The real-time speed of physical RNG based on chaotic laser is now limited under 5 Gb/s, although the reported RNG claims that an ultrafast speed of Tb/s is possible in theory. The main issues that restrict the real-time speed of RNG based on chaotic laser are from two aspects. The first aspect is electrical jitter bottleneck confronted by the electrical analog-to-digital converter (ADC). Specifically, most of the methods of extracting random numbers are first to convert the chaotic laser into an electrical signal by a photo-detector, then use an electrical ADC driven by radio frequency (RF) clock to sample and quantify the chaotic signal in electronic domain. Unfortunately, the response rate of ADC is below Gb/s restricted by the aperture jitter (several picoseconds) of RF clock in the sample and hold circuit. The second aspect comes from the complex post-processes, which are fundamental in current RNG techniques to realize a good randomness. The strict synchronization among post-processing components (e.g., XOR gates, memory buffers, high-order difference) is controlled by an RF clock. Similarly, it is also an insurmountable obstacle to achieve an accurate synchronization due to the electronic jitter of the RF clock. In this paper, we propose a method of ultrafast multi-bit physical RNG based on chaotic laser without any post-process. In this method, a train of optical pulses generated by a GHz mode-locked laser with low temporal jitter at a level of fs is used as an optical sampling clock. The chaotic laser is sampled in the optical domain through a low switching energy and high-linearity terahertz optical asymmetric demultiplexer (TOAD) sampler, which is a fiber loop with an asymmetrical nonlinear semiconductor optical amplifier. Then, the peak amplitude of each sampled chaotic pulse is digitized by a multi-bit comparator (i.e., a multi-bit ADC without sample and hold circuit) and converted into random numbers directly. Specifically, a proof-of-principle experiment is executed to demonstrate the aforementioned proposed method. In this experiment, an optical feedback chaotic laser is used, which has a bandwidth of 6 GHz. Through setting a sampling rate to be 5 GSa/s and selecting 4 LSBs outputs of the 8-bit comparator, 20 Gb/s (=5 GSa/s4 LSBs) physical random number sequences are obtained. Considering the ultrafast response rate of TOAD sampler, the speed of random numbers generated by this method has the potential to reach several hundreds of Gb/s as long as the used chaotic laser has a sufficient bandwidth.

We present three kinds of organic light-emitting devices (OLED) fabricated to achieve the emission of bright and pure white light. Device A, with a double-layered structure using 2-(2-hydroxyphenyl) benzothiazole (HBT) and poly (N-vinylcarbazole) (PVK) as the emitting layer (EML) and the hole transport layer (HTL) respectively, could realize the blue-green light emission. Bis-(2-(2-hydroxyphenyl) benzothiazole)zinc (Zn(BTZ)2), synthesized with zinc acetate dihydrate and HBT to form a complex, is used as main EMLs in a similar structure to fabricate devices B and C. Bright and pure white light emissions can be obtained from device C which was fabricated with a green-white emitting host Zn(BTZ)2 and red dopant 5,6,11,12-tetraphenylnaphthacene (rubrene). The maximum quantum efficiency of device C could reach 0.63%, and the corresponding brightness and CIE coordinates were 4000 cd/m2 and (x = 0.341, y = 0.334) at the driving voltage of 20 V.

This study used a dog model to determine the optimal temperature of percutaneous microwave ablation that causes complete necrosis of liver but not the adjacent bowel, supporting the use of this method to specifically and effectively treat liver tumour abutting the bowel.Ultrasound-guided percutaneous microwave ablation of liver abutting the bowel was performed on healthy adult dogs. Temperature of the ablation margin was monitored and controlled through inserted thermal monitoring needles. Dogs were divided into three groups and received microwave ablation at 75-95°C, 65-75°C, or 55-65°C. Imaging and histological examination were used to evaluate the damage of the bowel adjacent to the ablated liver.Within one hour of treatment, the bowel adjacent to the ablated liver was seriously burned in the group receiving 75-95°C microwave ablation. Inflammation and congestion were found in the submucosa of the bowel in the group receiving 65-75°C microwave ablation. Minor inflammation was found in the mucosa of the bowel in the group receiving 55-65°C microwave ablation. Moreover, in the group receiving 55-65°C microwave ablation, ablated liver areas were covered with omenta, and histological examination revealed inflammatory reaction of the omenta 28 days after ablation.Microwave ablation at 55-65°C for 6 min is preferred for ablation of liver tissue abutting the bowel in dogs. These findings may provide some valuable reference for percutaneous microwave ablation of human liver tumour adjacent to the bowel.

Absolutely secure communication should be implemented only through the ‘one-time pad' proposed by Shannon, requires that physical random numbers with rates matched with the associated communication systems be used as secret keys. With the wide application of the WDM technology in optical communication, the single channel rate of the current digital communication system has exceeded 10 Gb/s and developed towards 100 Gb/s. To ensure the absolute security of such a large capacity communication, a large number of real-time, and secure random numbers are needed.#br#Secure random numbers are commonly produced through utilizing physical random phenomena, called physical random number generators. However, conventional physical random number generators are limited by the low bandwidth of the applied entropy sources such as thermal noise, photon-counting and chaotic electrical circuits, and thus have typical low bit rates of the order of Mb/s.#br#In recent years, chaotic lasers attracted wide attention due to their generation of secure, reliable and high-speed random number sequences, and so due to their coherent merits such as high bandwidth, large amplitude fluctuation and ease of integration. There have been lots of schemes based on laser chaos for high-speed random number generation, but most of them execute the random number extractions from the associated laser chaos in the electrical domain and thus their generation rates are faced with the well-known ‘electrical bottleneck'. On the other hand, all-optical random number generation (AO-RNG) methods are all signal processes in the optical domain, so they can efficiently overcome this rate limitation and have a great potential in generating ultrafast random numbers of several dozens or hundreds of Gb/s. However, there is no experimental report on its realization of AO-RNG. One of the obstacles in the way for the AO-RNG achievement is to implement the fast and real-time all-optical sampling of the entropy signals (i.e., laser chaos).#br#In this paper, we present a principal experimental demonstration of the feasibility in the all-optical sampling of the chaotic light signal through constructing a TOAD-based all-optical sampler with a polarization-independent semiconductor optical amplifier (SOA). Specifically, we experimentally generate chaotic laser signals using an optical feedback semiconductor laser and finally complete a 5 GSa/s real-time and high-fidelity all-optical sampling of the chaotic laser with a bandwidth of 6.4 GHz. Further experimental results show that whether the optical sampling period is proportional to the external cavity feedback time or not has a great effect on the weak periodic suppression of the chaotic signal: only when both of them are out of proportion, can the weak periodicity of the original chaotic signal be effectively eliminated; and this is favorable for the generation of high-quality physical random numbers. To the best of our knowledge, it is the first time to realize all-optical sampling of chaotic signal in experiments.

We demonstrate experimentally a low switching energy and high-linearity all-optical sampler based on terahertz optical asymmetric demultiplexer (TOAD) composed of a nonlinear semiconductor optical amplifier (SOA) with a multiple quantum well structure. Effects of the sampling pulse power and asymmetric offset of SOA on the shape, width and amplitude of sampling windows are analyzed in detail respectively. It is found that the sampling pulse power has no effect on both the shape and the width of sampling windows, but has a significant effect on the window amplitude. Meanwhile there exists an optimal power which maximizes the sampled output and determines the switching energy of TOAD. The asymmetric offset of SOA from the center position in the loop determines the width of sampling windows and has great influences on both the shape and the amplitude of the sampling window. The sampling windows with different widths have approximately the same rise edge due to the fast response of SOA for the sampling pulse. However, the normalized amplitude of sampling windows firstly increases sharply with the increase of the asymmetry, then gradually flattens out, and tends to be stable in the end. In addition, the switching energy and linearity of TOAD are studied. The switching energy is as low as 25 fJ, and the linearity is as high as 0.99. Moreover, at different window widths, the switching energy of TOAD remains the same and the sampling windows have a very good linearity. However, the sensitivity of a TOAD sampler with different width is different: the wider the sampling window, the higher the sensitivity and the larger the corresponding dynamic range.

The geometry, spin multiplicity, magnetic moment, electronic density of states and the spin density of single-layer trigonal graphene quantum dots with zigzag edges have been systematically investigated using density functional theory with the generalized gradient approximation under different sizes. The calculated results such as lattice constants are in good agreement with experimental data and indicate that the system behaves like metal, while the electrons with up spins occupy the Fermi energy. The influence of quantum size effect is remarkable in the system of small size. It is also found that the sp2 hybridization and nonbonding electrons play an important part in the single-layer trigonal graphene quantum dots, just like in graphene. The spin multiplicity and magnetic moment of the system increase with the increase of the system size. Based on our calculation, the total magnetic moment of the system mainly comes from the nonbonding electrons on the 2p orbital of the zigzag boundary. Our calculation may be helpful in designing devices based on trigonal graphene quantum dots.