Mating behavior and sex pheromone release rhythm of Holotrichia parallela(Coleoptera: Melolonthidae)

Mating behavior and sex pheromone release rhythm of Holotrichia parallela was studied in this research. The maximum mating times were 3 for female and 4 for male. Average mating times were 1.06 for female and 0.91 for male. L-isoleucine methyl ester(LIME), a major component of pheromone, increased gradually from 14:00 and peaked at 19:00, then dropped sharply at 20:00 and remained low at 24:00.(R)-(-)-linalool(referred as linalool below) maintained similar levels throughout the study period. Calling and mating activity significantly decreased LIME titer, but not linalool. Analyses of 11 samples collected during calling days(20 d-70 d) revealed that LIME production was affected by female age. LIME titers increased from 20 d to 45 d, and decreased from 45 d to 70 d. While linalool titers remained at similar levels at all sampling dates. The highest ratio between LIME and linalool was 12 and the lowest was 4. Field tests confirmed that the most attractive ratios of LIME: linalool in early season(June 1 to 20) and late season(August 1 to 20) were 6:1, while in the most serious injury stage(June 20 to August 1) was 12:1. This is the first report about circadian rhythmicity of sex pheromone in Holotrichia parallela, which provides a basis for controlling it in field.

Demonstration of a diode-pumped dual-wavelength metastable krypton laser

Diode-pumped rare gas lasers are potential candidates for high-energy and high-beam quality laser systems.Currently,most investigations are focused on metastable Ar lasers.The Kr system has the unique advantages of higher quantum efficiency and lower discharge requirements for comparison.In this paper,a diode-pumped metastable Kr laser was demonstrated for the first time.Using a repetitively pulsed discharge at a Kr/He pressure of up to approximately1500 Torr,metastable Kr atoms of more than 10^(13)cm^(-3)were generated.Under diode pumping,the laser realized a dual-wavelength output with an average output power of approximately 100 mW and an optical conversion efficiency of approximately 10% with respect to the absorbed pump power.A kinetics study involving population distribution and evolution was conducted to analyze the laser performance.

Vertical profiles of biogenic volatile organic compounds as observed online at a tower in Beijing

Vertical profiles of isoprene and monoterpenes were measured by a proton transfer reactiontime of flight-mass spectrometry(PTR-ToF-MS) at heights of 3,15,32,64,and 102 m above the ground on the Institute of Atmospheric Physics(IAP) tower in central Beijing during the winter of 2016 and the summer of 2017.Isoprene mixing ratios were larger in summer due to much stronger local emissions whereas monoterpenes were lower in summer due largely to their consumption by much higher levels of ozone.Isoprene mixing ratios were the highest at the 32 m in summer(1.64±0.66 ppbV) and at 15 m in winter(1.41±0.64 ppbV) with decreasing concentrations to the ground and to the 102 m,indicating emission from the tree canopy of the surrounding parks.Monoterpene mixing ratios were the highest at the 3 m height in both the winter(0.71±0.42 ppbV) and summer(0.16±0.10 ppbV) with a gradual decreasing trend to 102 m,indicting an emission from near the ground level.The lowest isoprene and monoterpene mixing ratios all occurred at 102 m,which were 0.71±0.42 ppbV(winter) and 1.35±0.51 ppbV(summer) for isoprene,and 0.42±0.22 ppbV(winter) and0.07±0.06 ppbV(summer) for monoterpenes.Isoprene in the summer and monoterpenes in the winter,as observed at the five heights,showed significant mutual correlations.In the winter monoterpenes were positively correlated with combustion tracers CO and acetonitrile at 3 m,suggesting possible anthropogenic sources.

Fast screening compositions of PM2.5 by ATR-FTIR： Comparison with results from IC and OC/EC analyzers

Chemical speciation of fine particles or PM2.5 collected on filters is still a cosily and time- consuming task. In this study, filter-based PM2.5 samples were collected during November-December 2013 at four sites in Guangzhou, and the major components were fast screened （~ 7 rain per filter sample） by Attenuated Total Reflectance （ATR）-Fourier Transform Infrared Spectroscopic （FTIR） in comparison with that measured by Organic carbon/Element carbon （OC/ EC） analyzer and Ion Chromatography （IC）. The concentrations of nitrate, ammonium, sulfate, primary organic carbon （POC） and secondary organic carbon （SOC） measured by OC/EC and IC analyzers were better correlated with their infrared absorption peak heights at 1320 cm 1 for nitrate, 1435, 3045 and 3215 cm^-1 for ammonium, 615 cm^-1 for sulfate, 690, 760 and 890 cm^-1 for POC and 1640 and 1660 cm^-1 for SOC respectively, during polluted days （PM2.5 〉 75 μg/m^3） than during clean days （PM2.5〈 75 μg/m^3）. With the evolution of a haze episode during our field campaign, the concentrations of the major PM2.5 components displayed consistent variations with their infrared absorption peak heights, suggesting ATR-FTIR could be a fast and useful technique to characterize filter-based PM2.5 compositions particularly during pollution events although cautions should be taken when PM2.5 levels are low. Notably, elevated PM2.5 mass concentrations occurred with enhanced ratios of [NO^-3][SO^2-4] and [NH^＋4]/[SO^2-4], implying that nitrogenous components play vital roles in the PM2.5 pollution events in the study region.

Hybridization induced ion-barrier effect for the label-free and sensitive electrochemical sensing of Hepatocellular Carcinoma biomarker of miRNA-122

A label-free and sensitive electrochemical biosensing strategy for a hepatocellular carcinoma biomarker of miRNA-122 has been proposed based on hybridization induced ion-barrier effect on the electroactive sensing interface.First,a bifunctional electroactive electrode with the nanocomposite of Prussian blue(PB)and gold nanoparticles(AuNPs)was prepared through a two-step electrodeposition process.The PB endows the electrode excellent K^(+)-dependent voltammetric signal and the AuNPs act as the matrix for the self-assembly immobilization of the thiolated probe DNA.Upon specific hybridization of probe DNA with the target miRNA-122,the formed double duplex induced the ion-barrier effect,which blocked the diffusion of the K^(+)from the bulk solution to the electrode surface.As a result,the voltammetric signal of the PB on the electrode was surpressed,and thus the target miRNA-122 was monitored.The sensing assay showed that the miRNA-122 could be analyzed in the concentration range from 0.1 fmol/L to 1.0 nmol/L,with a detection limit of 0.021 fmol/L.The practical applicability of the biosensor was also verified by the spiking serum assay.

Post-Newtonian parameter γ in generalized non-local gravity

We investigate the post-Newtonian parameter 7 and derive its formalism in generalized non-local （GNL） gravity, which is the modified theory of general relativity （GR） obtained by adding a term m2n-2 R -nR to the Einstein-Hilbert action. Concretely, based on parametrizing the generalized non-local action in which gravity is described by a series of dynamical scalar fields ~i in addition to the metric tensor g μ v, the post-Newtonian limit is computed, and the effective gravitational constant as well as the post-Newtonian parameters are directly obtained from the generalized non-local gravity. Moreover, by discussing the values of the parametrized post-Newtonian parameters 9,, we can compare our expressions and results with those in Hohmann and Jarv et al. （2016）, as well as current observational constraints on the values of γ in Will （2006）. Hence, we draw restrictions on the nonminimal coupling terms F- around their background values.