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Chain-like peptides and DNA share obvious similarities in terms of chain hybridization; thus, replacing DNA with peptides to create bioactivities not only has high theoretical feasibility but also provides a new bottom-up synthetic strategy.

A fatigue life prediction method is developed for the high-pressure hydrogen storage vessel based on theoretical research and experimental verification. Firstly, the finite element model of vessel was built considering wound angle of head, thickness and number of the composite layer, then simulation was performed. The optimum range of autofrettage pressure was obtained by FEA with consideration of the DOT-CFFC and CGH2R standards. The influence of autofrettage pressure, metal liner thickness, and fiber thickness on vessel fatigue life was discussed under internal pressure cyclic load. Finally, the experimental verification was carried out. It was found that fatigue failure first occurred in middle cylinder. The experiment results agree well with theory analysis. Their average error is 6.33%.

DNA origami has created complex structures of various spatial dimensions. However, their versatility in terms of function is limited due to the lower number of the intrinsic building blocks

The lung microbiota have been found to be substantially altered in numerous pulmonary disorders, and crosstalk between the host pathophysiology and lung microbiota plays critical roles in the regulation of disease states. The aim of this study was to investigate dynamic changes in the lung microbiota during different stages of acute lung injury and acute respiratory distress syndrome (ALI/ARDS). Rats receiving an intraperitoneal administration of lipopolysaccharide (LPS) were sacrificed at 12 and 48 h after injection, and the hematological parameters, serum cytokine levels, and histological characteristics of the lung tissue and lung microbiota were assessed. After LPS injection, along with fluctuations of systemic cytokine levels and the onset and regression of pulmonary edema, the diversity, components, and functionalities of the pulmonary microbiota underwent significant dynamic changes. The volatility of the α-diversity indices narrowed after LPS injection, and the indices significantly decreased 48 h later. The abundance of 18 genera and functionality of adenosine triphosphate–binding cassette (ABC) transporters, pentose phosphate, and bacterial chemotaxis pathways were found to significantly differ between specified time points. Several significant correlations between the components and functionalities of the lung microbiota and indicative symptoms of ALI/ARDS were also observed. Brevibacterium was correlated with cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-10, and IL-6 and with hematological percentage of neutrophils (NEU%); Wnt, Notch, and chronic myeloid leukemia signaling pathways were correlated with IL-1β; mitogen-activated protein kinase (MAPK) signaling pathway–yeast was correlated with IL-10; and the pathways of ascorbate and aldarate metabolism and basal transcription factors were correlated with platelet-related indicators. The correlations between the lung microbiota and indicative symptoms of ALI/ARDS identified in this study support further investigation into the underlying mechanism of host–microbiota interactions during lung injury and repair.

Objective: To investigate the prevalence of human papillomavirus (HPV) in archival head and neck cancer (HNC) collected from the Tong-Liao area, which is located in east Inner Mongolia, China. Methods: The presence of HPV in 54 HNCs and 25 benign biopsies was detected and the sequence variation of the E6 gene in HPV-positive samples was analyzed to determine their lineage/sublineage classification. Results: HPV was detected in only 4 out of 54 HNCs and no benign biopsies were found to be HPV-positive. After further p16INK4a immunostaining, only 3 cases of HNC were positive for both HPV and p16INK4a. Phylogenetic analysis of the isolated E6 gene shows that the HPV 16, HPV 31, and HPV 58 isolated in this study belong to lineage A. Conclusions: The prevalence of HPV in HNC from this area is very low. The lineage/sublineage classification of the 3 HPV types in HNC in this area is consistent with the previous reported data of HPV lineage distribution in cervical cancer within China.

Infrared thermography (IRT) is introduced to measure the in-plane thermal conduction of woven carbon fiber reinforced polymers (CFRP). According to the principle of modulated laser heating, the relationship between the phase gradient and the in-plane thermal diffusivity has been deduced, and the experimental platform was established to test the 6 groups of CFRP test specimens with varied porosity. The measured infrared radiation signal was normalized by taking glassy carbon as the reference material, and the Gaussian filtering was applied to removing the noise of infrared thermal images. The experiment results show that the in-plane thermal conduction law in various directions is related to its conduction direction owing to the anisotropy of the CFRP. The in-plane thermal diffusivity of test specimens with different levels of porosity in each direction can be measured when the modulated laser frequency is lower than 1 Hz. In addition, the thermal diffusivity in each direction decreases with the increase of test specimens' porosity.

A new opal photonic crystal (PC) sensing material, allowing label-free detection of transferrin (TRF), is proposed in the current study. This photonic crystal was prepared via a vertical convective self-assembly method with monodisperse microspheres polymerized by methyl methacrylate (MMA) and 3-acrylamidophenylboronic acid (AAPBA). FTIR, TG, and DLS were used to characterize the components and particle size of the monodisperse microspheres. SEM was used to observe the morphology of the PC. The diffraction peak intensity decreases as the TRF concentration increase. This was due to the combination of TRF to the boronic acid group of the photonic crystal. After condition optimization, a standard curve was obtained and the linear range of TRF concentration was from 2 × 10–3 ng/mL to 200 ng/mL. Measurement of TRF concentration in simulated urine sample was also investigated using the sensing material. The results indicated that the PC provided a cheap, label-free, and easy-to-use alternative for TRF determina...

The responsive photonic crystals (PC) are promising sensing materials owning to their response signal self-expression, but how to attach the recognition element efficiently and how to improve the sensitivity are still challenging. Au nanoparticles (Au NPs), which possess high reactive activity and localized surface plasmon resonance (LSPR) effect, provide a strategy. So, Au NPs are introduced to opal PC, in order to not only amplify the optical signal but also facilitate the fixation of recognition element onto PC. Furthermore, the signal enhancement mechanism is investigated and a universal PC sensing material is developed. This PC is easy-prepared and can reach ultrasensitive detection without label. Coupled with the enhancement of Au NPs, the PC can respond to the trace target with the concentration down to 10−12 g/mL. Simultaneously, the detection of hazardous chemicals can be achieved by replacing the recognition element. This design extensively broadens the PC application in clinical assays, food safety, environmental monitoring, etc.

The purpose of this study was to understand cervical cancer prevention-related knowledge and attitudes among female undergraduate students from different ethnic groups within China. We conducted a survey among ethnically diverse female students from the Minzu University of China, in Beijing in October, 2014.Questionnaires from 493 participants aged from 16 to 26 years were included in the final database. The seven ethnic groups included in the final analysis were Han, Korean, Mongolian, Uyghur, Tibetan, Hui, and Tujia. Compared to the Han Chinese, the members of the other six ethnic groups had lower cervical cancer knowledge levels. The knowledge scores of Mongolian and Korean students were significantly lower than those of the Han Chinese. The willingness to accept cervical cancer prevention efforts also differed across different ethnic groups. After adjusting for age and place of residence, the acceptance of cervical cancer screening among the Tibetan, Uyghur, and Korean groups was significantly lower than among the Han Chinese, with different related decision-making factors in each group. Cervical cancer prevention-related public education is an urgent need in China. Extra consideration of ethnic differences should be taken into account when designing and improving new current cervical cancer prevention programs.

This study established ultra-performance liquid chromatography coupled with a photodiode array detector for determining psilocin and its pharmacokinetics in rat plasma after orally administering an extract of Gymnopilus spectabilis. The extract was separated on an ODS C18 column (2.3 μm, 100 mm × 2.1 mm I.D.) by gradient elution with (A) water containing 50mM AcONH(4) and (B) acetonitrile. The wavelength was set at 265 nm and the injection volume was 10 μL. Under these conditions, the calibration curve was linear over the concentration range 0.2-20 μg/mL with a correlation coefficient of r(2)=0.9992. The inter- and intraday precision levels were less than 7% and the accuracies (%) were within the range 92.0-102.5%. The method was sufficiently valid to be applied to a pharmacokinetics study of psilocin in rat plasma. The pharmacokinetic parameters of psilocin in rat plasma after the oral administration of a G. spectabilis extract were as follows: C(max), 0.43 ± 0.12 μg/mL; T(max), 90 ± 2.1 min; AUC(0→t), 1238.3 ± 96.4 (μg/mL) min; and T(1/2), 117.3 ± 40.3 min.

High-performance liquid chromatography (HPLC) and capillary electrophoresis (CE) were used to identify five active components in the modified herbal decoction Bo-Yang-Hwan-O-Tang (mBHT), i.e., amygdalin, decursin, paeoniflorin, salvianolic acid B, and calycosin-7-O-β-D-glycoside. These components were identified by comparing their retention times and mass spectra with those of reference compounds. The conditions of both analytical methods were optimized and validated. Sufficient separation of target analytes was achieved using a buffer consisting of 40 mM sodium borate and 60 mM sodium dodecylsulfate (SDS) containing 10% methanol (pH 9.5) at 250 nm for CE analysis and gradient elution with a water-methanol mobile phase and ultraviolet (UV) photodiode array detector (DAD) at 250 nm for HPLC analysis. The mBHT components were determined within 65 min by HPLC and 16 min by CE. All calibration curves showed high linearity (R > 0.999) within the ranges tested. Intra-day and inter-day precision were less than 1.6% and 1.8% for HPLC and 2.5% and 4.8% for CE, respectively. The accuracy of the methods ranged from 98.8% to 102.3% for HPLC and from 95.9% to 108.2% for CE.

The current study demonstrates the reversal of enantiomer migration order (EMO) in capillary electrophoresis (CE) based separations of sibutramines (SIB) as a function of the concentration of two types of cyclodextrin (CD), native β-CD and acetyl-β-CD. At normal working concentrations (10mM) of either CD, (S)-SIB migrated first. However, at CD concentrations greater than 10mM, (R)-SIB was the first to migrate. This study describes factors involved in determining EMO for sibutramine enantiomers at low and high concentrations of CDs. The reversal of EMO could be explained in terms of the opposing effects of the stability and the limiting complex mobility of the SIB-CD complexes. The enantioseparation of SIB with methyl- and 2-hydroxypropyl-β-CD was possible based on differences in the binding constants of complexes. However, reverse EMO was not observed because of equal mobilities of SIB enantiomers complexed with methyl- and 2-hydroxypropyl-β-CD.

Sibutramine enantiomers were separated successfully by capillary zone electrophoresis using substituted cyclodextrins as chiral selectors. The effects of cyclodextrin concentration, pH, voltage, buffer type, and electrolyte concentration on the migration time and resolution of enantiomers were examined. Separation of sibutramine enantiomers on an unmodified fused silica capillary (total length, 54 cm; effective length, 45 cm) was achieved using a mixed buffer of 20 mM phosphate/10 mM citrate containing either 5 mM methyl-β-cyclodextrin (pH 4.3) or 5 mM carboxymethyl-β-cyclodextrin (pH 6.5). Samples were injected with a pressure of 50 mbar for 5 s and were detected at a wavelength of 223 nm. The established method showed good precision and accuracy, with intra- and inter-day variations of less than 2.9 and 4.7%, respectively, and recoveries of 95.7 - 103.8%. The stability constants of (R)- and (S)-sibutramine demonstrated that the resolution of sibutramine enantiomers was attributable primarily to the difference in stability constants. When this optimized method was applied to the determination of sibutramine enantiomers in commercial drug formulations, it proved to be economical and convenient, affording sufficient accuracy, precision, and reproducibility as well as sensitivity and selectivity.

A biologically active benzophenanthridine alkaloid, 6-methoxydihydrosanguinarine (MS), was isolated from Hylomecon plants. Although enantiomers of MS can be separated by chiral HPLC, its isomers rapidly form a racemic mixture in methanol. The rate constants for the racemization of MS enantiomers were 9.20 × 10 −4 s −1 and 9.95 × 10 −4 s −1 for (+)-MS and (−)-MS, respectively, as determined by dynamic HPLC and chiral chromatography. This unusually rapid racemization may originate from the formation of a stable iminium ion intermediate, sanguinarine. Therefore, the variety of biological activities exhibited by MS may be attributable to a combination of (+)-MS, (−)-MS, and sanguinarine.

A simple high performance liquid chromatographic method was developed to evaluate the quality of Moutan Cortex Radicis based on chromatographic fingerprints that characterize eight pharmacological compounds, namely, gallic acid, paeoniflorin, galloyl paeoniflorin, benzoic acid, quercetin, benzoylpaeoniflorin, paeoniflorigenone, and paeonol. These compounds were identified by their characteristic UV profiles and the mass spectroscopy data, and their contents were determined by HPLC. The chromatographic separation was performed on a C18 column by gradient elution with 0.05% formic acid in water and acetonitrile. The methodological validation gave acceptable linearities (r = 0.9996) and recoveries (ranging from 99.4∼103.1%). The limits of detection (LOD) of these compounds ranged from 10 to 30 µg/mL. The representative chromatographic fingerprints of Moutan Cortex Radicis were obtained by analyzing 20 batches of samples collected from markets in Korea and China. For the efficient evaluation of quality for the commercial Moutan Cortex Radicis it is recommended that the total content of the six characteristic compounds should contain more than a minimum of 2% and that the content of total paeoniflorin and paeonol should exceed a minimum of 1.5% of dry weight of Moutan Cortex Radicis.

To explore the nucleotide sequence variability of the E2 gene in high-risk HPV types in cervical cancer patients from Sichuan province, China, the E2 genes of eight high-risk HPV types were amplified and sequenced. Several novel nucleotide substitutions and deletions were observed. The lineages to which the isolates belonged were determined by phylogenetic analysis, employing the sequence of the representative lineages/sublineages in the coherent classification and nomenclature system as references. This study updates the lineage distribution data on high-risk HPV types in Southwest China and helps broaden understanding of the polymorphism of the E2 gene.

Focus on the deficiency of model handling in the virtual training; it puts forward a method of the model dynamic importing. Through the establishment of virtual prototype and definition of model precision, this paper establishes the geometric model and details bases. And according to the corresponding relation between the information of the model and the precision in the post information base, it realizes the importing of the model dynamically. And the necessity and feasibility of the technology is illuminated taking tunnel boring machine (TBM) for example.

All the enantiomers of methoxydihydrosanguinarine (MS), ethoxydihydrosanguinarine (ES) and iso-propoxydihydrosanguinarine (PS) were separated by chiral HPLC. They were further identified by comparing the retention times of authentic standards as well as LC-MS. Interestingly, the approximately same conversion rates for the formation MS from ES or PS and the slower conversion of MS in isopropanol compared to ethanol demonstrated two step mechanism in the reaction of alkoxysanguinarine in alcohols, which is composed of the initial formation of sanguinarine as a planar intermediate and the addition of alcohol to intermediate as possible rate limiting step. Thus, sanguinarine has a pivotal role in the chemical behavior of alkoxysanguinarine in alcoholic solvents. Such possible variation of the structure of sanguinarine may be the source of its diverse biological activities.

An adaptive particle swarm optimization(APSO) algorithm is presented to solve the problem that the standard particle swarm optimization(PSO) algorithm is easy to fall into a locally optimized point, where inertia weight is nonlinearly adjusted by using population diversity information. Velocity mutation factor and position interchange factor are both introduced. The APSO algorithm thus improves its solvability for global optimization to avoid effectively the precocious convergence. The new algorithm is applied to reactive power optimization of the standard IEEE-30-bus power system as instances, and the simulation results show the effectiveness and feasibility of APSO algorithm for the reactive power optimization. It is proved to be efficient and practical during the reactive power optimization.

With the development of city, the planning of underground power pipelines becomes more and more important. The layout is difficult because pipelines situate underground. They are invisible and related with many factors such as roads, buildings, transformer substations, other pipelines and so on. In order to improve planning efficiencies, a new technique based on virtual reality is presented. Firstly, a virtual scene is constructed according to the existing pipeline and related environment. And the area partition method is introduced to increase rendering speed. So the designer can browse the virtual underground space at their choice. It makes the planning work simple. Then, a planning drawing and a three-dimensional demonstration will be automatically produced on the basis of the planning message. When the technique was applied to power planning of Pudong District in Shanghai, China, it saved planning and lay out time about 20%.

[This corrects the article DOI: 10.7150/ijms.29322.]., (© The author(s).)