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Hollyhock (Alcea rosea (Linn). Cavan) is an herbaceous flowering plant with significant applications in urban greening, soil remediation, and traditional medicine. However, its genetic diversity and molecular characteristics at the population level have not been explored yet. Here, the phenotypic and genetic diversity of 162 hollyhock accessions from China revealed extensive variation among 11 traits and strong correlations between several quantitative traits. Whole-genome re-sequencing of 32 randomly chosen accessions identified 10,468,760 core single-nucleotide polymorphisms (SNPs) distributed evenly across the genome, except for on chromosome 21, and the average nucleotide diversity (π) was calculated to be 0.00397. Principal component analysis showed that these 32 accessions could be divided into four subpopulations, which was in agreement with the population structure analysis, and the subpopulations were strongly correlated with geographic location. A neighbor-joining dendrogram displayed similar clusters, except for accessions HuB25 and HLJ28, which formed two separate clusters. Our findings illuminate the genetic diversity in hollyhock and provide valuable information for hollyhock breeding.

Our previous study had demonstrated that oral administration of Houttuynia cordata polysaccharides (HCP) without in vitro antiviral activity ameliorated gut and lung injuries induced by influenza A virus (IAV) in mice. However, as macromolecules, HCP was hard to be absorbed in gastrointestinal tract and had no effect on lung injury when administrated intravenously. The action mechanism of HCP was thus proposed as regulating the gut mucosal-associated lymphoid tissue (GALT). Actually, HCP treatment restored the balance of Th17/Treg cells firstly in GALT and finally in the lung. HCP reduced the expression of chemokine CCL20 in the lung and regulated the balance of Th17/Treg carrying CCR6+ (the CCL20 receptor), which was associated with specific migration of Th17/Treg cells from GALT to lung. In vitro, HCP inhibited Th17 cell differentiation through the downregulation of phospho-STAT3, whereas it promoted Treg cell differentiation by upregulating phospho-STAT5. Furthermore, its therapeutic effect was abolished in RORγt-/- or Foxp3-/- mice. These findings indicated that oral administration of macromolecular polysaccharides like HCP might ameliorate lung injury in IAV infected mice via directly regulating the balance of Th17/Treg cells in gut-lung axis. Our results provided a potential mechanism underlying the therapeutic effect of polysaccharides on pulmonary infection.

Anti-complementary activity-guided fractionation led to the isolation of a new abietane diterpene (

Anti-complementary activity-guided fractionation led to the isolation of a new abietane diterpene (1) and twenty-five known compounds (2���26) from the twigs and leaves of Juniperus tibetica. All the compounds were isolated from J. tibetica for the first time. The structure of 1 was assigned by spectroscopic data and X-ray crystallography analysis. Five lignans (2, 3, 7, 9 and 10), two flavones (19 and 22), and one coumarin (23) exhibited anti-complementary activity with CH50 values ranging from 0.3 to 3.69 mM.

980-nm-upconverted 530 and 550 nm Er

Dispersion relation is established for Er(NbO3)3 phosphor, which is an excellent candidate for optical thermometry based on thermal effect of Er3+ fluorescence intensity ratio. To achieve it, Er(NbO3)3 phosphor was dispersed into α-bromonaphthalene liquid to form a suspension. Then, refractive index values of the suspension were measured at wavelengths 473, 589.3, 632.8, 980, 1311 and 1553 nm by dropping it onto a plastic sheet. Subsequently, refractive indices of the Er(NbO3)3 phosphor were evaluated from these measured index values using Maxwell-Garnett relation. Finally, based on these Er(NbO3)3 index values, which have an error 0.03, a three-oscillator Sellmeier equation that considers contributions from Nb–O group, plasmons in far UV regime and phonons in infrared region is established. In parallel, a Cauchy dispersion equation is also established. Both equations can well fit the experimental data and the refractive indices predicted by the two equations can be regarded as identical within the error 0.03.

980-nm-upconverted 530 and 550 nm Er3+ green fluorescence spectra of Er3+/Yb3+-codoped NaGd(WO4)2 submicron crystals were measured in the temperature range of 298–383 K. A sextuple ratiometric thermometry is proposed. It is established on the basis of six schemes of fluorescence intensity ratio (FIR) that considers three component peaks of the 530 nm emission band and two component peaks of the 550 nm emission band, which involve electronic transitions between two Stark sublevels of Er3+. The study shows that the phosphor shows strong green fluorescence, which is verified by measured quantum yield, and thermally stable spectral structure desired for the sextuple ratiometric thermometry. All of the six FIR schemes display highly efficient sensing performances with slightly different thermal sensitivities. Each scheme gives a temperature value and the six schemes give an averaged result. In parallel, we have also carried out an ex vivo experimental study on the temperature characteristics of the green fluorescence of the phosphor. Almost same results have been obtained, verifying biological applicability of the phosphor. The ex vivo experimental results also show that the sextuple thermometry increases considerably the accuracy and reliability of temperature measurement in comparison with the conventional intensity integration method.

Forest bio-fuel, a new type renewable energy, has attracted increasing attention as a promising alternative. In this study, a new method called Sparse Partial Least Squares Regression (SPLS) is used to construct the proximate analysis model to analyze the fuel characteristics of sawdust combining Near Infrared Spectrum Technique. Moisture, Ash, Volatile and Fixed Carbon percentage of 80 samples have been measured by traditional proximate analysis. Spectroscopic data were collected by Nicolet NIR spectrometer. After being filtered by wavelet transform, all of the samples are divided into training set and validation set according to sample category and producing area. SPLS, Principle Component Regression (PCR), Partial Least Squares Regression (PLS) and Least Absolute Shrinkage and Selection Operator (LASSO) are presented to construct prediction model. The result advocated that SPLS can select grouped wavelengths and improve the prediction performance. The absorption peaks of the Moisture is covered in the selected wavelengths, well other compositions have not been confirmed yet. In a word, SPLS can reduce the dimensionality of complex data sets and interpret the relationship between spectroscopic data and composition concentration, which will play an increasingly important role in the field of NIR application.

Numerical method is used to build the entity model and finite element model of a marine pump, modal analysis shows that modal frequency is not equal to the operating frequency and the resonance is not produced in the pump. The finite element method is used to calculate the shock load which is the request of GJB. The allowable strength at vertical, longitudinal and horizontal direction of the pump is analyzed, and the anti-shock behavior of the pump is checked too. The results show this type pumps are not destroyed wholly and can be working normally in the shock environment, which satisfy the requirements of GJB. But the bracket position of the pump is suffered great compressive stress which leads to the designed and strengthened again.