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Abstract Because of the low detection probability and recognition efficiency of the single-band signal of an infrared point target, the multi-band composite detection probability is analyzed and a multi-band recognition method is proposed. By using the binary hypothesis method, we can conveniently deduce the multi-band theoretical detection threshold and obtain the composite detection probability and false alarm probability. The numerical simulation results show that multi-band composite detection ability is superior to that of single-band. For the difficult classification between background and target spectral signals with serious interference noise in reality, this paper proposes a highly effective spectral signal recognition method based on the optimized AdaBoost algorithm. By virtue of the high classification accuracy of the AdaBoost algorithm, with the Pruning classifier as a basic classifier to be learnt, the proposed method abandons any abnormal data that seriously deviate from the mean value center of the correction classification data, the end result of which reduces the number of iterations and enhances the classification effect of the AdaBoost algorithm. Compared with other algorithms from test results, the optimized AdaBoost algorithm has higher recognition accuracy and quicker computation, and it reduces the sensitivity to noise to prevent the phenomenon of over-fitting. [ABSTRACT FROM AUTHOR]

Multispectral detection signals are relatively stable and complementary to single spectral detection signals with deficiencies of severe scintillation and poor anti-interference. To take advantage of multispectral radiation characteristics in the application of infrared target detection, the concept of a multispectral radiation envelope is proposed. To build the multispectral radiation envelope model, the temperature distribution of an aerial infrared target is calculated first. By considering the coupling heat transfer process, the heat balance equation is built by using the node network, and the convective heat transfer laws as a function of target speed are uncovered. Then, the tail flame temperature distribution model is built and the temperature distributions at different horizontal distances are calculated. Second, to obtain the optimal detection angles, envelope models of reflected background multispectral radiation and target multispectral radiation are built. Finally, the envelope characteristics of the aerial target multispectral radiation are analyzed in different wavebands in detail. The results we obtained reflect Wien’s displacement law and prove the effectiveness and reasonableness of the envelope model, and also indicate that the major difference between multispectral wavebands is greatly influenced by the target speed. Moreover, optimal detection angles are obtained by numerical simulation, and these are very important for accurate and fast target detection, attack decision-making and developing multispectral detection platforms. [ABSTRACT FROM AUTHOR]

Abstract: Specific TNFR-Fc productivity (q TNFR-Fc) in CHO cells was found to decrease by 68% at a cell density of 6×106 cells/mL compared to that at 2×106 cells/mL. In order to unravel the reasons for the reduced q TNFR-Fc at high cell density, an in-depth study of physiological factors, gene transcription and post-translational process was carried out. Physiological factors including cell biomass, intracellular protein and cell cycle distribution were not affected by cell density. Transcriptional analysis revealed that TNFR-Fc mRNA level at 2×106 cells/mL was almost 2-fold higher than that at 6×106 cells/mL. Moreover, rather than mRNA stability, the slower transcriptional rate led to the decreased mRNA level. By analyzing the post-translational process, we found that the protein assembly rate and transport rate from the endoplasmic reticulum to the Golgi at high cell density were significantly lower than those at low cell density. Therefore, the decreased q TNFR-Fc at high cell density was correlated with the reduction in both mRNA level and post-translational processing rate. It was further found that the decreased mRNA level and post-translational processing rate might be linked to the apparent increase in CO2 partial pressure (pCO2) at high cell density, which had resulted in the reduction in intracellular pH in CHO cells. [Copyright &y& Elsevier]

Abstract: The specific productivity of tumor necrosis factor receptor-immunoglobulin G1 Fc fusion (TNFR-Fc) (q TNFR-Fc) in Chinese hamster ovary (CHO) cells at 30°C was approximately 5-fold higher than that at 37°C. To investigate reasons for increased q TNFR-Fc at low culture temperature, TNFR-Fc mRNA levels were determined by real-time PCR. It was found that like q TNFR-Fc, the relative TNFR-Fc mRNA level was increased by lowering culture temperature, and more importantly, the kinetics of the increase in TNFR-Fc mRNA levels were in accordance with the changes in q TNFR-Fc. The results demonstrated that the increased transcriptional level of TNFR-Fc was responsible for the increased q TNFR-Fc at low culture temperature. Enhanced levels of mRNA could derive from increased gene copy number, improved mRNA stability, or enhanced transcriptional rate. There was not a big change of gene copy number by lowering culture temperature. The transcriptional rate of TNFR-Fc was slightly decreased at 30°C, compared to 37°C. However, mRNA stability of TNFR-Fc was significantly improved by lowering culture temperature. The half-life of TNFR-Fc mRNA was 5.55h at 30°C, whereas that was 3.69h at 37°C. Taken together, the reasons for the increased q TNFR-Fc in CHO cells at low culture temperature were mainly the enhanced TNFR-Fc mRNA levels, which resulted from the improved mRNA stability, rather than the changes in the gene copy number or the transcriptional rate. [Copyright &y& Elsevier]

In an effort to improve TNFR-Fc production in GS-CHO cells, batch cultures were performed to investigate the effects of low culture temperature on TNFR-Fc production. It was observed that low culture temperatures resulted in cell cycle arrest in the G1 phase, led to suppressed cell growth, and prolonged the culture period. Although the highest TNFR-Fc concentration was achieved with a culture temperature of 32°C at 247.4 mg/L, the maximum q of 15.7 pg/cells/day was achieved at 30°C. Because the inhibition effect on cell growth at 30°C compromised its beneficial effects specifically to TNFR-Fc productivity, TNFR-Fc concentration at this temperature was not significantly increased. Furthermore, the increase in productivity of specific TNFR-Fc at low culture temperatures was also found to be due to an increase in the transcriptional level of the TNFR-Fc gene, determined by RT-PCR analysis. In addition, low culture temperatures had no significant effect on the degree of sialylation of TNFR-Fc. Taken together; a biphasic cultivation process developed in a fed-batch mode with a low temperature-production phase enhanced TNFR-Fc production by GS-CHO cells and therefore offers major potential for bioprocess optimization. [ABSTRACT FROM AUTHOR]

• An idea of multispectral image fusion detection for infrared point target is proposed. • A new local contrast descriptor of multiscale homogeneous feature (MHF) is proposed. • The multiscale homogeneous feature based infrared point target detection method is proposed. In view of the difficult detection of infrared dim point target from complex backgrounds, a multiscale homogeneous feature (MHF) based multispectral image fusion detection method is proposed in this paper. Inspired by the local contrast measure (LCM), we extract two local statistical features from the perspective of the homogeneity of gray difference distribution to characterize local structure of the infrared point target. Based on these two local features, we obtain the MHF map that can effectively highlight the potential point targets and suppress the backgrounds simultaneously. For the pixel-size electronic noise (PSEN) and some similar local structures to the point target, the multispectral image fusion detection is a positive way to alleviate these interferences and promote the robustness of the dim point target detection. Experimental results on six real scenarios and synthetic scenarios demonstrate that the proposed method not only works more stably for different target sizes and brightness, but also can achieve superior detection performance compared with the state-of-art detection methods. [ABSTRACT FROM AUTHOR]

[Display omitted] Isoreticular bimetal M−Cu−BTC has considerable potential in improving the sulfides removal performance of Cu–BTC. Herein, three transition metals, namely, Zn2+, Ni2+ and Co2+, were assessed to fabricate M−Cu−BTC, a desirable isoreticular bimetal. Results demonstrated the feasibility of using Zn2+ to fabricate an isoreticular bimetallic Zn–Cu–BTC. The Zn2+ doping content of Zn–Cu–BTC was varied to investigate its influence on the hydrogen sulfide (H 2 S) and methyl sulfide (CH 3 SCH 3) removal performance of Cu–BTC. The experimental results indicated that the sulfides removal performance of Zn–Cu–BTC increased and then decreased with increasing Zn doping content. The highest H 2 S and CH 3 SCH 3 removal capacities of 84.3 and 93.9 mg S/g, respectively, were obtained when the Zn2+ doping content was 17%. The hybridisation of Zn and Cu in Zn–Cu–BTC induced a strong interaction between them. This interaction increased the binding energies of H 2 S and CH 3 SCH 3 towards the Cu and Zn adsorption sites while weakening the bond order between Zn and Cu. The weakened bond order made the Zn–Cu bonds easier to form metal sulfides during desulfurization process, thereby synergistically enhancing sulphide removal. [ABSTRACT FROM AUTHOR]

Abstract In the parasitoid/polydnavirus/host system, polydnaviruses protect larva development in the host hemocoel by suppressing the host immune response. However, the negative effects on the parasitoid and the strategy of the parasitoid to deal with this disadvantage are still unknown. Microplitis bicoloratus bracovirus induces granulocyte apoptosis to suppress immune responses, resulting in an apoptotic haemolymph environment in which immature M. bicoloratus larva develop. Here, we determined the transcriptional profiles of immature M. bicoloratus across five time-points throughout the immature developmental process from egg to third instar. Dynamic gene expression pattern analysis revealed clear rapid changes in gene expression characteristic of each developmental stage, indicating faster sequential unambiguous functional division during development. Combined with the proteome of the host haemolymph, immature parasitoids likely secreted a Cu/Zn superoxide dismutase to reduce reactive oxygen species generation by symbiotic bracovirus. These data established a basis for further studies of parasitoid/host interactions and identified a novel positive self-protection mechanism for the parasitoid. Highlights • Immature parasitoids secreted a Cu/ZnSOD. • Cu/ZnSOD reduces ROS triggered by bracovirus. • A positive self-protection mechanism. [ABSTRACT FROM AUTHOR]

Previous determinations of the optimal stabilizing pile location have generally been based on the idealized assumption of arc-shaped sliding surfaces. This assumption, however, may be inconsistent with the actual situation of most common irregular shapes, such as the step shape; as a result, determinations based on this assumption tend to involve considerable error. This paper presents a strategy, termed the local safety partitioning (LSP) methodology, for accurately determining optimal pile locations for step-shaped configurations. Instead of assuming the sliding surface to be arc-shaped, this strategy considers the actual sliding shapes. A new index termed the local safety factor is introduced for measuring the stabilities of local landslide masses, and this method employs the Swedish slice method to calculate the value of the index. The LSP methodology consists of four procedures: slicing the landslide mass into blocks, calculating the local safety factor of each sliced block, dividing the landslide mass into local partitions based on the previous step, and identifying the optimum pile position using previously identified partitions. The performance of the presented methodology is illustrated using the Jinle No. 2 landslide case for well-rounded demonstration and using the Yancun landslide case for additional validation. The results indicate that analysis of a reinforced landslide employing the LSP methodology acquires the largest safety factor and smallest deflection, shear force and bending moment on the pile body compared with any other case from a series of positions that incorporate traditional positions for arc-shaped sliding surfaces. The presented methodology provides a simple but accurate determination of the optimal stabilizing pile location for stepped sliding surfaces, although it may involve errors and unexpected limitations when applied to arc shapes and peculiar scenarios. [ABSTRACT FROM AUTHOR]

Abstract: A novel and simple optical fiber structure with a section of no-core fiber for measuring relative humidity (RH) is presented. Moisture-sensitive materials HEC/PVDF are used to form the hydrogel coating on the no-core fiber by dip impregnation method. Under different humidity conditions, the humidity induced refractive index changes on the outside coating of no-core fiber will lead to the variations of the optical output power. The different lengths of no-core fiber are tested at the two wavelengths of 1310nm and 1550nm, respectively. The results show that the structure with 2cm no-core fiber has a higher RH sensitivity of 0.196dB/%RH at 1310nm and a better linearly response when the RH is lower than 75%. Furthermore, the optical output powers are measured with the rise and drop of RH, and the four times repetition are also recorded, which all demonstrate the good stability and repeatability of our proposed structure. [Copyright &y& Elsevier]

The measurement of node importance in complex networks has an important impact on the stability and robustness of networks, such as stopping the spread of disease and rumors and preventing power grids from being powered off. A variety of network centricity criteria are used to evaluate the importance of nodes, while each of them accompanied by a single criterion has its own shortcomings and limitations. A novel method is therefore proposed to rank node importance based on combining the existing centrality criteria. This paper considers degree centrality, closeness centrality, and betweenness centrality and raises an integrated measuring method to evaluate node importance in complex networks. In our method, the weight of each criterion is calculated by entropy weighting method which overcomes the impact of the subjective factor, and the Vlsekriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method is used for ranking nodes' importance. Finally, four experiments are conducted based on four actual networks to verify the feasibility and effectiveness of the proposed method. The experimental results demonstrate that the performance of ranking node importance of the proposed method is better than a single centrality criterion. • Entropy weighting method and VIKOR are combined to rank importance of nodes. • Weight of criterion is obtained using entropy weighting method. • Experiments show that the proposed method outperforms a single centrality criterion. • The proposed method can reduce the frequency of nodes with the same ranking. [ABSTRACT FROM AUTHOR]