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Glucose is a main carbon and energy source for virus proliferation and is usually involved in the glycolysis, pentose phosphate pathway (PPP), and tricarboxylic acid cycle (TCA cycle) pathways. In this study, we investigated the roles of glucose-related metabolic pathways during the replication of infectious spleen and kidney necrosis virus (ISKNV), which has caused serious economic losses in the cultured Chinese perch (Siniperca chuatsi) industry. We found that ISKNV infection enhanced the metabolic pathways of the PPP and the TCA cycle at the early stage of the ISKNV infection cycle and enhanced the glycolysis pathway at the late stage of the ISKNV infection cycle though the comprehensive analysis of transcriptomics, proteomics, and metabolomics. The advanced results proved that ISKNV replication induced upregulation of aerobic glycolysis at the late stage of ISKNV infection cycle and aerobic glycolysis were required for ISKNV multiplication. In addition, the PPP, providing nucleotide biosynthesis, was also required for ISKNV multiplication. However, the TCA cycle involving glucose was not important and necessary for ISKNV multiplication. The results reported here provide new insights into viral pathogenesis mechanism of metabolic shift, as well as antiviral treatment strategies.

Infectious spleen and kidney necrosis virus (ISKNV) has caused serious economic losses in the cultured mandarin fish (Siniperca chuatsi) industry in China. Host metabolism alteration induced by disease infection may be the core problem of pathogenesis. However, to date, little is known about the disease-induced fish metabolism changes. In this study, we first reported ISKNV, the fish virus, induced metabolism alteration. The metabolomics profiles of Chinese perch brain cells (CPB) post-ISKNV infection at progressive time points were analyzed using the UHPLC-Q-TOF/MS technique. A total of 98 differential metabolites were identified. In the samples harvested at 24 hours post-infection (hpi; the early stage of ISKNV infection), 49 differential metabolites were identified comparing with control cells, including 31 up-regulated and 18 down-regulated metabolites. And in the samples harvested at 72 hpi (the late stage of ISKNV infection), 49 differential metabolites were identified comparing with control cells, including 27 up-regulated and 22 down-regulated metabolites. These differential metabolites were involved in many pathways related with viral pathogenesis. Further analysis on the major differential metabolites related to glucose metabolism and amino acid metabolism revealed that both glucose metabolism and glutamine metabolism were altered and a metabolic shift was determined from glucose to glutamine during ISKNV infection cycle. In ISKNV-infected cells, CPB cells prefer to utilize glucose for ISKNV replication at the early stage of infection, while they prefer to utilize glutamine to synthetize lipid for ISKNV maturation at the late stage of infection. These findings may improve the understanding of the interaction between ISKNV and host, as well as provide a new insight for elucidating the ISKNV pathogenic mechanism.

First purchases of fruit are mainly dependent on aspects of appearance such as color. However, repeat buys of fruit are determined by internal quality traits such as flavor-related volatiles. Differences in volatile profiles in white- and red-fleshed peach fruit are not well understood. In the present study, peach cultivars with white- and red-fleshed fruit were subjected to sensory analysis using electronic nose (e-nose) to evaluate overview volatile profiles. Approximately 97.3% of the total variation in peach color-volatiles was explained by the first principle component 1 (PC1) and PC2. After analyzing sensory differences between peach fruit samples, 50 volatile compounds were characterized based on GC-MS. Multivariate analysis such as partial least squares discriminant analysis (PLS-DA) was applied to identify volatile compounds that contribute to difference in white- and red-fleshed peach fruit cultivars. A total of 18 volatiles that could separate peach fruit cultivars with different colors in flesh during ripening were identified based on variable importance in projection (VIP) score. Fruity note latone γ-hexalactone had higher contents in red-fleshed cultivars, while grassy note C6 compounds such as hexanal, 2-hexenal, (E)-2-hexenal, 1-hexanol, and (Z)-2-hexen-1-ol showed great accumulation in white-fleshed peach fruit.

[Objective] Improving the level of technological innovation in enterprises is the key to developing new quality productivity. The current phenomenon of population shrinkage in China’s cities is becoming more pronounced. This study aimed to explore from the perspective of enterprises how these spatial phenomena affect corporate technological innovation and to conduct an in-depth analysis of the mechanisms involved, thereby proposing policy recommendations for the spatial optimization of corporate technological innovation and the promotion of high-quality development. [Methods] Based on the data of China’s A-share listed companies in Shanghai and Shenzhen from 2009 to 2018, this study used the population data from the China Urban Construction Statistical Yearbook to construct the urban population shrinkage index and matched it with the cities where the listed companies operate. The impact of urban population shrinkage on corporate technological innovation was empirically tested using fixed effects models and difference-in-differences (DID) models. This research also delved into the mechanisms behind these impacts through theoretical analysis. [Results] The study found that: (1) Population shrinkage had a certain negative effect on both the input and output of corporate technological innovation; (2) Population shrinkage negatively affected corporate technological innovation through mechanisms such as the weakening of human capital, reduction in industrial agglomeration, and the crowding-out effect of financial investment; (3) The impact of population shrinkage on corporate technological innovation exhibited heterogeneity across industries, particularly affecting the technological innovation behavior of technology-intensive enterprises, while having no significant impact on labor-intensive and capital-intensive enterprises. [Conclusion] To enhance the input and output of corporate technological innovation, further promotion of balanced spatial population development and regional innovation cooperation is required, which advances regional integration.

In order to investigate the application potential of prolyl endopeptidase (PEP) in the enzymatic preparation of bone collagen peptides, the amino acid sequence characteristics of bovine bone collagen (BBC), porcine bone collagen (PBC) and chicken bone collagen (CBC) were comparatively analyzed, and their potential enzymatic cleavage sites and theoretical hydrolysis degrees were predicted. Collagen hydrolyzed by PEP at 55 ℃ and pH 8.0 was characterized by hydrolysis degree, molecular mass distributionand scanning electron microscopy (SEM). Infrared spectroscopy, X-ray diffraction (XRD) and circular dichroism (CD) spectroscopy were used to explore the structural changes of collagen during enzymatic digestion. The results showed that PEP could hydrolyze the three collagens. The hydrolysis degree of PBC was the highest (51.35%), followed by those of BBC (22.81%) and CBC (29.81%). The molecular masses of the three collagen hydrolysates were mostly distributed below 500 Da. Spectroscopic analysis showed that PEP destroyed the triple helix structure of collagen, and then degraded it. Therefore, PEP can efficiently enzymatically hydrolyze collagen into small molecule peptides, which provides a basis for the enzymatic preparation of functional collagen-derived peptides.

A novel meta steel with negative Poisson's ratio effect (termed as micro-NPR steel) is developed for rock support in deep underground engineering. It possesses high strength, high ductility, and high energy absorption characteristics. In this paper, static tension and modified dynamic drop hammer tests are performed on this novel material to investigate its mechanical properties first. Then based on this material, a new generation of micro-NPR anchor cable is developed and applied in field tests subjected to blasting dynamic loads. The results of laboratory tests reveal that the ultimate elongation of micro-NPR steel under dynamic impacts is more than 30% and it is over 1.5 times that of Q235; the plastic and total energy absorption of micro-NPR are both significantly higher than that of Q235. Field test indicates the fine controlling effect of micro-NPR anchor cable on surrounding rock mass under dynamic loads. Axial force confirms that micro-NPR cables can distribute and absorb the dynamic energy uniformly around the supported rock when subjected to dynamic disturbance, avoiding local failure induced by excessive stress concentration. The excavation compensation principle and energy-absorbing characteristics are used to explain the support mechanisms. Thus, micro-NPR material and anchor cable can control and prevent dynamic disasters in deep underground engineering effectively. [ABSTRACT FROM AUTHOR]

The VP2 structural protein of parvovirus can produce virus-like particles (VLPs) by a self-assembly process in vitro, making VLPs attractive vaccine candidates. In this study, the VP2 protein of canine parvovirus (CPV) was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells and pupae. Electron micrographs of VLPs showed that they were very similar in size and morphology when compared to the wild-type parvovirus. The immunogenicity of the VLPs was investigated in mice and dogs. Mice immunized intramuscularly with purified VLPs, in the absence of an adjuvant, elicited CD4(+) and CD8(+) T cell responses and were able to elicit a neutralizing antibody response against CPV, while the oral administration of raw homogenates containing VLPs to the dogs resulted in a systemic immune response and long-lasting immunity. These results demonstrate that the CPV-VLPs stimulate both cellular and humoral immune responses, and so CPV-VLPs may be a promising candidate vaccine for the prevention of CPV-associated disease.

An abstract of the article "Establishment and Clinical Application of a Liquid Chip Technology for High Throughput Screening Pathogens of Acute Contagious Respiratory Disease?" by Yusheng Chen and colleagues is presented.

An abstract of the article "An Optimal Method to Establish Non-small Cell Lung Cancer Model With Highly Brain Metastasis," Yusheng Chen and colleagues is presented.

Pure cooperative branch effects on one- and two-photon optical properties of conjugated derivatives are presented. AM1 calculations demonstrate that the electron density distribution of the frontier orbital and the dipole moment changes of the derivatives are related to the number of branches. The theoretical results show that not only the energy level of the frontier orbital could be mediated by the number of branches, but the HOMO-LUMO gap could be regulated. [ABSTRACT FROM AUTHOR]

A variety of new conjugated dyes bearing a benzophenone unit were synthesized, and the linear absorption and emission were determined. Two-photon absorption properties of the derivatives have been measured by a Ti:sapphire femtosecond laser tuning from 720 to 880 nm at intervals of 20 nm. One- and two-photon optical properties of the derivatives were found to be significantly dependent on their chemical structures. [ABSTRACT FROM AUTHOR]

Crack on piezoelectric ceramic is the main reason leading to failure of ultrasonic motors. A novel degradation feature extraction method based on discrete cosine transform (DCT) -singular value (SV) cross entropy was proposed in this paper. In order to improve the correlation with the crack, the DCT coefficients with the property of energy aggregation, were used to extract fault information. To avoid the influence of human factors in traditional DCT de-noising method, a matrix composed of DCT coefficients was constructed, and the SV cross entropy of the matrix was taken as the degradation feature for ultrasonic motor. A numerical simulated noise was added to the measured signal to verify the anti-noise performance of the feature. Analysis of the experimental results demonstrates that the proposed DCT-SV cross entropy is feasible and effective in indicating the degradation of piezoelectric ceramic in ultrasonic motor. [ABSTRACT FROM AUTHOR]

The solubilities of gatifloxacin, enrofloxacin, ciprofloxacin in SC-CO2 were determined by the dynamic method under pressures of 12-36 MPa and temperature of 313, 323, and 333 K. The consistency of the resulting solubility data was verified by the Mendez-Santiago and Teja model, Chrastil model, Bartle model, and K-J model and these models give comparable AARDs (between 6.70% and 13.51%). The compressed gas model and modified expanded liquid model were also used to correlate the resulting solubilities of the three fluoroquinolone drugs. By introducing the reference solubility and calculating the fugacity coefficient of the solute using the Carnahan-Starling-VDW hard sphere equation of state (CS-VDW EoS), the compressed gas model gives the AARDs between 0.86% and 23.65%. The intrinsic proximity of the model parameters in this model is also confirmed for the structurally similar fluoroquinolone drugs. This intrinsic proximity can be used in mutual solubility prediction between the fluoroquinolone drugs once the reference solubilities were known. The modified expanded liquid model gives the AARDs between 10.88% and 16.65% in solubility correlation. However, the predictive capability of the modified expanded liquid model based on the group contribution method needs to be improved further. [ABSTRACT FROM AUTHOR]