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To deal with the problem of carbon source lacking and the difficulties of waste activated sludge (WAS) disposal in wastewater treatment plant (WWTP), nitrite was added into WAS fermentation system (NSF) to develop a new way to accomplish denitrification and WAS reduction simultaneously in this paper, and the effect of electron acceptor concentration (200, 400, 600, and 800 mg/L nitrite) on denitrification in NSF was studied. Experiment results showed that different NO2--N concentration of NSF systems presented different denitrification ability, the best denitrification performance was found in 400 mg/L, and it was investigated that the nitrite removal amount per unit of volatile suspended solid (VSS) reduction in different NSF systems was presented as this order: 400>600>200>800 (mg/L), with values of 0.66, 0.60, 0.46, 0.44 mg NO2--N /mgVSS-reduction respectively. Furthermore, there was no volatile fatty acids (VFAs) accumulation in 400mg/L NO2--N concentration system, while different level of accumulation in other NO2--N concentration systems was found, which meant denitrifiers in 400mg/L NSF could utilize carbon sources much better than that of others. Additionally, all the systems showed a great sludge reduction capacity, with more than 40% of VSS reduction.

This paper presents a kind of basis functions used for image directional representation, which are obtained from the pseudo polar Fourier transform-based directional filter banks (PPFT-DFBs). The basis functions so obtained have the attractive properties of i) flexible direction and ii) arbitrary number of subbands. More specifically, we give the derivation of the basis function from the equivalent directional filter of PPFT-DFBs. Further, we analyze the properties of basis functions and their corresponding basis images. Experiments are given to testify the flexibility of basis functions and their efficiency in directional representation.

We proposed a novel pH measurement method based on two-photon fluorescence excitation of a dual-wavelength pHsensitive dye combined with scanning near-field optical microscopy (SNOM) that can be used to evaluate mitochondrial activity. Mitochondria produce ATP using a proton concentration (pH) gradient generated between both sides of their inner membrane. Thus, pH distribution around mitochondria can change with time when mitochondria produce ATP. This pH distribution has attracted interest because of its influence on necrotic cell death. Because ATP depletion causes necrotic cell death, measurement of pH distribution around mitochondria is expected to lead to clarification of the mechanism underlying necrotic cell death. However, it is very difficult to accurately measure pH around mitochondria using conventional pH measurement methods. In this study, a dual-wavelength pH-sensitive dye was excited locally using two-photon fluorescence excitation. In addition, collection-mode SNOM was used to avoid reabsorption by collecting the fluorescent light directly from a florescence point. Using this method, we successfully calibrated pH and observed temporal variations in pH after dropwise addition of acid. Moreover, mitochondrial activity was successfully observed based on these pH changes.

A novel method to observe pH distribution by dual wavelength fluorescent ratiometric pH measurement by scanning near-field optical microscopy (SNOM) is developed. In this method, in order to investigate not only the pH of mitochondrial membrane but also its distribution in the vicinity, a pH sensitive fluorescent reagent covers mitochondria instead of injecting it to mitochondria. This method utilizes a dual-emission pH sensitive dye and SNOM with a themally-pulled and metal-coated optical fiber to improve the spatial resolution. Time-dependence of Fluorescent intensity ratio (FIR) under acid addition is investigated. As the distances between the dropped point and the SNOM probe becomes closer, the time when FIR changes becomes earlier. The response of mitochondria under supplement of nutrition is studied by using this method. While the probe is near to mitochondria, the ratio quickly becomes to increase. In conclusion, it was confirmed that the temporal variation of pH can be detected by this method, and pH distribution in the vicinity of mitochondria is able to be measured by this method.

Six calixarene bonded silica gel stationary phases were prepared and characterized by elemental analysis, infrared spectroscopy and thermal analysis. Their chromatographic performance was investigated by using PAHs, aromatic positional isomers and E- and Z-ethyl 3-(4-acetylphenyl) acrylate isomers as probes. Separation mechanism based on the different interactions between calixarenes and analytes were discussed. The chromatographic behaviors of those analytes on the calixarene columns were influenced by the supramolecular interaction including pi-pi interaction, space steric hindrance and hydrogen bonding interaction between calixarenes and analytes. Notably, the presence of polar groups (-OH, -NO(2) and -NH(2)) in the aromatic isomers could improve their separation selectivity on calixarene phase columns. The results from quantum chemistry calculation using DFT-B3LYP/STO-3G* base group were consistent with the retention behaviors of PHAs on calix[4]arene column.

Researchers have proved that the general computing capability of the mainstream programmable GPU (Graph Processing Unit, the core of graphic card) is more powerful than that of the popular CPU (Central Processing Unit) recently [1]. In this paper, we attempt to develop such a desktop grid, in which the programmable GPUs? powerful general computing ability could be linked in. The hierarchical topology and benchmarks based scheduling algorithm are adopted in the grid to improve the efficiency of the desktop grid. We contrast the performances of GPUs general computing enabled and non-enabled desktop grid to prove the superiority of GPUs? linking supported by some simulation experiments.

A practical method for residue analysis of 2,4-D, dicamba and 2,4,5-T in baked tobacco leaves has been developed using nonaqueous CE (NACE). The herbicide residues of 2,4-D, dicamba and 2,4,5-T in tobaccos were extracted by ultrasonication with ethyl acetate, followed by a cleanup procedure with gel permeation chromatography. The separation of 2,4-D, dicamba and 2,4,5-T by NACE was optimized based on orthogonal experiment design with four factors at three levels. The optimal NACE condition was established with the running buffer of 40.0 mmol/L ammonium acetate in 90% CH3CN (apparent pH 10.2), and the applied voltage of -25 kV over a capillary of 50 microm id x 46 cm (37.5 cm to the detector window), which gave a baseline separation of 2,4-D, dicamba and 2,4,5-T within 15 min. The LOD were ca. 0.4-0.6 microg/mL for the three herbicides, whereas the overall recovery ranged from 80.8 to 84.1%. The proposed method has been successfully applied to measure 300 real tobacco samples, and the residue profiles of the three herbicides in tobacco samples were obtained and evaluated.

Based on field survey, information collection and experts consultation, the quantitative grading index system and assessment standards for preference conservation of rare and endangered plant species of forest-meadow ecotone in Sanjiangyuan Nature Reserve were established by using the methods and principles of systematical analysis. The quantitative grading index system included endangered coefficient, genetic coefficient, and useful value coefficient. In addition, 10 indicators used to evaluate endangered grading and conservation priorities sequenc, were also included in 3 subsystems respectively. Furthermore, the weights of 3 subsystem and 10 indicators were given through experts consultation and analytic hierarchy process. Endangered coefficient and conservation priorities coefficient, which respectively described the endangered grading, and preferential conservation of plant species were calculated by mathematic models and computer program. Contrasting to the standards of endangered grading and conservation priorities for plant species, we quantitatively evaluated the status of endangered and conservation priorities of plant species. The results showed that the number of endangered species was 4, vulnerable species 68, lower risk species 179, safety species 695; the number of the first class species was 8, the second class species 78, the third class species 164, and the delayed conservation species 696. Finally, we discussed the problems of indicator system and its weight, the relationship between endangered grading and conservation priorities sequence, and the spatial scale problem of plant species assessment.

An injury to a peripheral nerve in animals often leads to signs of neuropathic pain including hyperalgesia to heat, cold and mechanical stimuli. The role of injured and intact nerve fibers in mechanical hyperalgesia was evaluated in rats subjected to an L5 spinal nerve ligation-and-cut (‘modified SNL lesion’). To assess the contribution of injured afferents, an L5 dorsal rhizotomy was performed immediately before, or 7 days after the modified SNL lesion. To study the role of adjacent intact spinal nerves, an L4 dorsal rhizotomy was performed 7 days after the modified SNL lesion. The up–down method of Dixon (Dixon WJ, Annu Rev Pharmacol Toxicol 1980;20:441–462) was used to measure the paw withdrawal threshold to mechanical stimuli at three sites on the rat hindpaw corresponding to the L3, L4, and L5 dermatomes. We found that the modified SNL lesion produced a significant, lasting (>20 days) decrease of the mechanical withdrawal threshold. The severity and duration of mechanical hyperalgesia varied across testing sites. The L5 and L4 dermatome test sites developed the most severe and lasting mechanical hyperalgesia. In contrast, the L3 testing site developed significantly less severe and shorter lasting mechanical hyperalgesia. L5 dorsal rhizotomy, by itself, produced a transient decrease in mechanical withdrawal thresholds. L5 dorsal rhizotomy performed before, or 7 days after, the modified SNL lesion did not prevent or resolve the observed decrease in mechanical withdrawal thresholds. L4 dorsal rhizotomy performed 7 days after the modified SNL lesion resulted in an immediate reversal of mechanical withdrawal thresholds back to baseline values. These results suggest that, after L5 spinal nerve ligation-and-cut, mechanical hyperalgesia develops and persists independent of input from injured afferents. We propose that the Wallerian degeneration that develops after a nerve injury leads to interactions between the degenerating fibers of the injured spinal nerve and the intact fibers of adjacent spinal nerves. This leads to changes in the intact fibers that play a critical role for both initiation and maintenance of mechanical hyperalgesia.

A mitochondrion has a pH gradient between the two sides of its inner membrane in order to produce adenosine triphosphate (ATP). Because ATP depletion causes numerous diseases, the measurement of the pH value around the mitochondrion is expected to clarify the mechanism of these diseases. In this study, a dual-wavelength pH-sensitive dye was excited by two-photon absorption initiated using a femtosecond pulse laser. In addition, fluorescence from the dye was directly collected from the fluorescent point using the collection-mode probe of a scanning near-field optical microscope. By this proposed method, a pH calibration curve was obtained from the fluorescent intensity ratio of the dye solution, and temporal pH variations with 0.1 s time resolution following the addition of acid were observed. Moreover, mitochondrial activity on the basis of the pH changes was successfully observed in three different mitochondrial densities.

In this work, a simple method based on reverse-phase high-performance liquid chromatography (HPLC) with tris(2,2-bipyridyl)ruthenium(II) [Ru(bpy)32+]-modified single Pt wire electrogenerated chemiluminescence (ECL) detector for the determination of three antiemetic drugs was developed. The proposed detector was based on Ru(bpy)32+ immobilized on a Pt wire surface with Nepem-105D ion exchange solution. The method allows for the simultaneous detection of these antiemetic drugs in human serum and offers short analysis times. In this HPLC-ECL system, luminescence reagent Ru(bpy)32+ was immobilized, thus, no Ru(bpy)32+ delivery system is needed, furthermore, stable ECL response of analytes can obtained. Besides conserving the expensive reagent, the experimental setup is also simplified.

Selective micro heat sintering (SMHS)-type 3D printing technology is a widely applied method in rapid prototyping, which uses an electric heating component to sinter non-metallic powder. It requires precise control of the heating component’s energy and its sintering time. Temperature is one of the key factors that affect the forming quality of fused-type 3D printing technology. Aiming at the nonlinear and time-delay characteristics of temperature control in fused-type 3D printing, a fuzzy control method based on variable universe fuzzy control was studied. This fuzzy control method adopts a set of nonlinear expansion-contraction factors to make the variable universes change with the adaptive error, which can help acquire adaptive temperature adjustment in the rapid prototyping process control. The results of the simulation and experiment showed that the controlled temperature response was faster, the overshoot was smaller, and the stability was better compared to the conventional fuzzy proportion integration differentiation (PID) algorithm after the temperature reached the target temperature. The printed results indicated that the universe fuzzy PID control can effectively improve the accuracy of the workpiece shapes and that the density distribution of the workpiece is increased, which can help improve the forming quality.