Sum frequency generation spectroscopy of the attachment disc of a spider

The pyriform silk of the attachment disc of a spider was studied using infrared-visible vibrational sum frequency generation (SFG) spectroscopy. The spider can attach dragline and radial lines to many kinds of substrates in nature (concrete, alloy, metal, glass, plant branches, leaves, etc.) with the attachment disc. The adhesion can bear the spider's own weight, and resist the wind on its orb web. From our SFG spectroscopy study, the NH group of arginine side chain and/or NH$_{2}$ group of arginine and glutamine side chain in the amino acid sequence of the attachment silk proteins are suggested to be oriented in the disc. It was inferred from the observed doublet SFG peaks at around 3300 cm$^{-1}$ that the oriented peptide contains two kinds of structures.Comment: 21 pages, 8 figure

Synthesis and investigation of deoxyribonucleic acid/locked nucleic acid chimeric molecular beacons

To take full advantage of locked nucleic acid (LNA) based molecular beacons (LNA-MBs) for a variety of applications including analysis of complex samples and intracellular monitoring, we have systematically synthesized a series of DNA/LNA chimeric MBs and studied the effect of DNA/LNA ratio in MBs on their thermodynamics, hybridization kinetics, protein binding affinity and enzymatic resistance. It was found that the LNA bases in a MB stem sequence had a significant effect on the stability of the hair-pin structure. The hybridization rates of LNA-MBs were significantly improved by lowering the DNA/LNA ratio in the probe, and most significantly, by having a shared-stem design for the LNA-MB to prevent sticky-end pairing. It was found that only MB sequences with DNA/LNA alternating bases or all LNA bases were able to resist nonspecific protein binding and DNase I digestion. Additional results showed that a sequence consisting of a DNA stretch less than three bases between LNA bases was able to block RNase H function. This study suggested that a shared-stem MB with a 4 base-pair stem and alternating DNA/LNA bases is desirable for intracellular applications as it ensures reasonable hybridization rates, reduces protein binding and resists nuclease degradation for both target and probes. These findings have implications on the design of LNA molecular probes for intracellular monitoring application, disease diagnosis and basic biological studies

High-temperature humidity sensors based on WO3-SnO2 composite hollow nanospheres

National Natural Science Foundation of China [61376073]Three kinds of humidity sensors were fabricated from WO3-SnO2 composite hollow nanospheres (WO3-SnO2 HNS), WO3 nanoparticles (WO3 NPs) and SnO2 nanoparticles (SnO2 NPs). WO3-SnO2 HNS were prepared by a facile hydrothermal process with a diameter and thickness of about 550 nm and 30 nm, respectively. Temperature-dependent properties of as-prepared humidity sensors were investigated at various values of relative humidity and temperature. It was found that the WO3-SnO2 HNS humidity sensor showed good performance at 80 degrees C. The response time, recovery time and sensitivity were evaluated while switching the humidity between 35% RH and 98% RH. The response time decreased from 289 to 29 s, the recovery time reduced from 22 to 8 s, and the sensitivity changed from 16.2 to 11.4 as the work temperature was raised from 24 to 80 degrees C. An opposite humidity sensing phenomenon was observed between WO3 NPs and SnO2 NPs at a high temperature, which might explain the temperature-dependent properties of the WO3-SnO2 HNS humidity sensor. This work could stimulate a right approach to design practical humidity sensors with high sensitivity, long stability and fast response

Developing a Green Bonds Market: The Case of China

European Business Organization Law ReviewGerman

Natural Products from Actinomycetes Associated with Marine Organisms

The actinomycetes have proven to be a rich source of bioactive secondary metabolites and play a critical role in the development of pharmaceutical researches. With interactions of host organisms and having special ecological status, the actinomycetes associated with marine animals, marine plants, macroalgae, cyanobacteria, and lichens have more potential to produce active metabolites acting as chemical defenses to protect the host from predators as well as microbial infection. This review focuses on 536 secondary metabolites (SMs) from actinomycetes associated with these marine organisms covering the literature to mid-2021, which will highlight the taxonomic diversity of actinomycetes and the structural classes, biological activities of SMs. Among all the actinomycetes listed, members of Streptomyces (68%), Micromonospora (6%), and Nocardiopsis (3%) are dominant producers of secondary metabolites. Additionally, alkaloids (37%), polyketides (33%), and peptides (15%) comprise the largest proportion of natural products with mostly antimicrobial activity and cytotoxicity. Furthermore, the data analysis and clinical information of SMs have been summarized in this article, suggesting that some of these actinomycetes with multiple host organisms deserve more attention to their special ecological status and genetic factors

Theories-based determinants analysis of Hib-combined vaccine hesitancy in China: A multi-group structural equation modeling

Objectives To explore determinants of Hib-combined vaccine hesitancy in Chinese parents, and to provide scientific intervention measures to tackle vaccine hesitancy. Methods 2,531 parents were recruited from local healthcare centers in Zhejiang Province by accidental sampling, and completed the self-developed online questionnaire with voluntary participation. Health Belief Model and Model of Determinants of Vaccine Hesitancy were applied to construct the framework of research. Multi-group Structural Equation Modeling was performed to explore the effects of determinants of vaccine hesitancy across various socio-economic status (SES). Results Hib-combined vaccine hesitancy for total sample was 2.184 ± 0.777 (95%CI: 2.153–2.214), and most of them were in low (n = 1436, 56.7%) level. Low SES group (2.335 ± 0.763, 95%CI: 2.271–2.400) had significantly highest vaccine hesitancy. For total sample, Self-Efficacy and Cues to Action presented −0.517 and −0.437 of standard total effect on Vaccine Hesitancy, respectively. The Multi-group Structural Equation Model with satisfying goodness of fit in SES groups ($${\chi ^2}$$ = 1616.074, df = 314, $${\chi ^2}$$/df = 5.147, CFI = 0.973, TLI = 0.966, SRMR = 0.027, RMSEA = 0.041) showed that Cues to Action imposed −0.621 (95%CI: −0.867–0.389, p < .001) of major standard total effect on Vaccine Hesitancy in low SES group, while Self-Efficacy imposed −0.560 (95%CI: −0.668–0.444, p < .001) and −0.685 (95%CI: −0.841–0.454, p < .001) of principal standard total effect on Vaccine Hesitancy in middle and high SES groups, respectively. Conclusions Hib-combined vaccine hesitancy in Chinese parents was low, and the lower the SES, the higher the vaccine hesitancy. Cues to Action and Self-Efficacy played primary role in declining vaccine hesitancy for parents at low SES, and at middle and high SES, respectively

Penalized spline estimation for functional coefficient regression models

The functional coefficient regression models assume that the regression coefficients vary with some "threshold" variable, providing appreciable flexibility in capturing the underlying dynamics in data and avoiding the so-called "curse of dimensionality" in multivariate nonparametric estimation. We first investigate the estimation, inference, and forecasting for the functional coefficient regression models with dependent observations via penalized splines. The P-spline approach, as a direct ridge regression shrinkage type global smoothing method, is computationally efficient and stable. With established fixed-knot asymptotics, inference is readily available. Exact inference can be obtained for fixed smoothing parameter [lambda], which is most appealing for finite samples. Our penalized spline approach gives an explicit model expression, which also enables multi-step-ahead forecasting via simulations. Furthermore, we examine different methods of choosing the important smoothing parameter [lambda]: modified multi-fold cross-validation (MCV), generalized cross-validation (GCV), and an extension of empirical bias bandwidth selection (EBBS) to P-splines. In addition, we implement smoothing parameter selection using mixed model framework through restricted maximum likelihood (REML) for P-spline functional coefficient regression models with independent observations. The P-spline approach also easily allows different smoothness for different functional coefficients, which is enabled by assigning different penalty [lambda] accordingly. We demonstrate the proposed approach by both simulation examples and a real data application.

Secure sharing method of network data transmission based on multi-layer encryption technology

In order to ensure the effect of network data transmission in scientific research institutions and avoid network information from being attacked and damaged, a secure sharing method of network data transmission based on multi-layer encryption technology is proposed. Combined with multi-layer encryption technology, the network data transmission security protocol is constructed to ensure the security and integrity of the initial file. The network information transmission security evaluation system is further constructed. The network transmission path security of scientific research institutions is tracked, evaluated and tested in real time. The network data transmission security sharing platform is constructed to ensure the safe sharing of massive and complex data Experiments have proved that the security and sharing processing effect of the network data transmission security sharing method based on multi-layer encryption technology are significantly improved compared with the traditional methods, and fully meet the research requirements