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The Japanese pine sawyer, Monochamus saltuarius, as a beetle vector of Bursaphelenchus xylophilus (pine wood nematode), is an economically important forest pest in Eurasia. To feed on the phloem and xylem of conifers, M. saltuarius needs to overcome various stress factors, including coping with entomopathogenic bacteria and also various plant secondary compounds (PSCs). As an important adaptation strategy to colonize host trees, M. saltuarius deposit eggs in oviposition pits to shield their progeny. These pits harbor bacterial communities that are involved in the host adaptation of M. saltuarius to the conifers. However, the composition, origin, and functions of these oviposition pit bacteria are rarely understood. In this study, we investigated the bacterial community associated with M. saltuarius oviposition pits and their ability to degrade PSCs. Results showed that the bacterial community structure of M. saltuarius oviposition pits significantly differed from that of uninfected phloem. Also, the oviposition pit bacteria were predicted to be enriched in PSC degradation pathways. The microbial community also harbored a lethal strain of Serratia, which was significantly inhibited. Meanwhile, metatranscriptome analysis indicated that genes involved in PSCs degradation were expressed complementarily among the microbial communities of oviposition pits and secretions. In vitro degradation showed that bacteria cultured from oviposition pits degraded more monoterpenes and flavonoids than bacteria cultured from uninfected phloem isolates. Disinfection of oviposition pits increased the mortality of newly hatched larvae and resulted in a significant decrease in body weight in the early stages. Overall, our results reveal that M. saltuarius construct oviposition pits that harbor a diverse microbial community, with stronger PSCs degradation abilities and a low abundance of entomopathogenic bacteria, resulting in the increased fitness of newly hatched larvae.

In order to improve the hardness and tribological performance of Ti6Al4V alloy, NiCoCrAlY–B4C composite coatings with B4C of 5%, 10% and 15% (mass fraction) were fabricated on its surface by laser cladding (LC). The morphologies, chemical compositions and phases of obtained coatings were analyzed using scanning electronic microscope (SEM), energy dispersive spectrometer (EDS), and X-ray diffraction (XRD), respectively. The effects of B4C mass fraction on the coefficient of friction (COF) and wear rate of NiCoCrAlY–B4C coatings were investigated using a ball-on-disc wear tester. The results show that the NiCoCrAlY–B4C coatings with different B4C mass fractions are mainly composed of NiTi, NiTi2, α-Ti, CoO, AlB2, TiC, TiB and TiB2 phases. The COFs and wear rates of NiCoCrAlY–B4C coatings decrease with the increase of B4C content, which are contributed to the improvement of coating hardness by the B4C addition. The wear mechanisms of NiCoCrAlY–B4C coatings are changed from adhesive wear and oxidation wear to fatigue wear with the increase of B4C content.

Purpose Cysteine-rich protein 2 (CSRP2), as a newly discovered oncogene, is overexpressed in several cancers. However, the specific role of CSRP2 and its potential mechanism remain incompletely understood in head and neck squamous cell carcinoma (HNSCC). Methods The expression of CSRP2 was explored in the Cancer Genome Atlas (TCGA) databases and the results were confirmed by immunohistochemistry tissue microarrays and Western blotting in HNSCC. The effect of CSRP2 on the cancer stemness and epithelial-to-mesenchymal transition (EMT) of HNSCC cells was investigated by sphere formation, wound healing and transwell assays. A series of in vitro and in vivo experiments were conducted to reveal the mechanisms by which CSRP2 modulated cancer stemness and EMT phenotypes in HNSCC. Results CSRP2 expression was markedly higher in HNSCC tissues than in non-tumor tissues, high CSRP2 expression was positively correlated with lymph node metastasis and recurrence. Noticeably, overall survival rate of HNSCC patients with high CSRP2 expression level presented worse prognosis. In addition, elevated CSRP2 expression was observed in several HNSCC cell lines and mouse HNSCC cell lines, and CSRP2 knockdown inhibited the sphere formation and apoptosis. Additionally, wound healing and transwell assay results showed that CSRP2 knockdown inhibited the migration and invasion ability of the HNSCC cells. Furthermore, we found that CSRP2 was closely associated with CSCs markers (CD44, BMI1 and CD133), EMT-transcription factor (Slug), new oncoprotein LAMTOR5, p-S6Ser235/236 and immune checkpoint (VISTA) using Tgfbr1/Pten conditional knockout mice model and mouse HNSCC cell line-derived xenograft models. Conclusions Our findings demonstrate that elevated expression of CSRP2 indicates poor prognosis and plays a key role in maintaining the cancer cell stemness and EMT features during the progression of HNSCC, suggesting that CSRP2 may serve as a new and valuable therapeutic target for HNSCC.

The formation of heterojunction structures can effectively prevent the recombination of photogenerated electron-hole pairs in semiconductors and result in the enhancement of photoelectric properties. Using TiO

Exploring the deep space of the universe is crucial to promote research on basic scientific issues, such as the origin of the solar system, evolution of planets, and origin of life. Using probes to detect deep-space objects has become the focus of the development of various aerospace powers. As the deep-space exploration task is performed far away from the earth, it is difficult to guarantee the safe and reliable operation of deep-space probes by relying on ground control networks to guide their navigation; as such, deep-space probes should have autonomous navigation ability. An autonomous navigation system based on sequence images has the advantages of low cost, low power consumption, full application, and simple data structure, which can effectively reduce the space and energy burden of the autonomous navigation system of deep-space probes, and is an ideal means to realize autonomous navigation in deep-space probes. However, because of the lack of prior information about deep-space exploration targets and systematic error in a deep-space complex environment, the autonomous navigation system based on sequence images is a typical under-observable system. To improve the accuracy and engineering practicability of typical autonomous navigation systems, it is necessary to guide the design and engineering realization of autonomous navigation systems based on theoretical research on observability. In response to the actual needs of observability theory research, in this paper, we first systematically expound the current research status of existing theories and methods from three aspects: characterization, determination, and quantification of the observability of nonlinear systems. Then, the observability analysis method of a class of under-observation systems—autonomous navigation systems based on sequence images—is investigated. The research status of observability for such systems is given, and the advantages and disadvantages of each method are discussed. Finally, by summarizing existing results, limitations in the observability research of under-observation systems at present and future development trends are discussed.

The dynamics response and power flow propagation in the L-shaped beam with finite dimension were investigated. A L-shaped beam dynamic model was established on the basis of Timoshenko beam theory (TBT) and Euler-Bernoulli beam theory (EBT). The analytical solution was obtained and the beam flexural and longitudinal motion was described by using the traveling wave approach. The effects of shear distortion and rotary inertia on the total power flow and its components were examined. Results shown that the structure resonant frequencies are obviously affected by the shear distortion and rotary inertia, especially for the medium and high frequency ranges. The power flow amplitude is obviously increased on the premise of considering the longitudinal vibration. Consequently, the longitudinal vibration should be considered for the power flow and its components in the L-shaped beam.

Imaging characteristics of stars and artificial targets in space are very similar in long-distance space-based observation as they are both light spots described by point spread function with a Gaussian distribution. In the condition of low signal-to-noise ratio, the signal of space artificial targets is faint on the image, which is covered with background and noise signals; thus, it is more difficult to recognize the faint space artificial targets from complex backgrounds. To solve this problem, this paper proposes a fast recognition algorithm for faint targets on the basis of matched filters. First, the imaging model of space artificial targets is built in the star tracking observation mode, wherein space artificial targets and stars appear as streaks and points, respectively. Therefore, the faint point target recognition problem is transferred to faint streak pattern recognition from light spot background. Second, the signal-to-noise ratio is used to define the faint degree of targets to evaluate the recognition limit of the algorithm. Then, a streak element pattern is designed. It is a part of the whole streak pattern; thus, the generation of streak patterns with varying lengths in the progress of matched filter can be avoided, so the calculation is decreased and the recognition speed is increased. Finally, to verify the fast recognition algorithm of faint targets, several images with stars and faint space artificial targets under different signal-to-noise ratios are simulated. The fast recognition algorithm of faint targets is tested using these simulation images; the results reveal that faint targets can be recognized from simulation images using this algorithm when the signal-to-noise ratio is above 0.5.

Achyranthes bidentata Blume (AB) is a health food and a sulfur-free herbal medicine that is one of the most heavily sulfur-fumigated herbs in the marketplace. In this work, a comprehensive approach using ultra-performance liquid chromatography coupled with quadrupole time-of-flight-MS (UPLC-Q-TOF-MS) and multivariate statistical analysis was developed to identify characteristic sulfur-fumigation markers, elucidate chemical transformation mechanisms and characterize the degree of sulfur-fumigation of AB. Non-fumigated and sulfur-fumigated AB samples were compared by UPLC-Q-TOF-MS/MS analysis. Three triterpene saponins (Betavulgarosides II–IV) and two amides (Feruloyl-4-O-methyldopamine and Moupinamide) were identified as characteristic markers, which were positively correlated with two active AB components, namely oleanic acid and ferulic acid, respectively. Moreover, the extent of the sulfur-fumigation under different weight ratios of sulfur to herbal materials (1:20, 1:40, and 1:80) was analyzed based on chemical transformations and sulfur dioxide residues. Further verification showed that the ratio of 1:40 within 1 h was reasonable and efficient for herb quality preservation and assurance. This study provides a reliable sulfur-fumigation protocol for the quality control of AB and other herbs.

In photovoltaic devices, more effective transfer of dissociated electrons and holes from the active layer to the respective electrodes will result in higher fill factors and short-circuit current densities and, thus, enhanced power conversion efficiencies (PCEs). Planar perovskite photovoltaics feature an active layer that can provide a large exciton diffusion length, reaching several micrometers, but require efficient carrier transport layers for charge extraction. In this study, we employed two nanocomposite carrier transfer layers—an electron transport layer (ETL) comprising [6,6]phenyl-C61-butyric acid methyl ester (PC61BM) doped with the small molecule 4,7-diphenyl-1,10-phenanthroline (Bphen), to enhance the electron mobility, and a hole transfer layer (HTL) comprising poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) doped with molybdenum disulfide (MoS2) nanosheets, to enhance the hole mobility. We used ultraviolet photoelectron spectroscopy to determine the energy levels of these composite ETLs and HTLs; atomic force microscopy and scanning electron microscopy to probe their surface structures; and transmission electron microscopy and synchrotron grazing-incidence small-angle X-ray scattering to decipher the structures of the ETLs. Adding a small amount (less than 1%) of Bphen allowed us to tune the energy levels of the ETL and decrease the size of the PC61BM clusters and, therefore, generate more PC61BM aggregation domains to provide more pathways for electron transport, leading to enhanced PCEs of the resulting perovskite devices. We used quantitative pump-probe data to resolve the carrier dynamics from the perovskite to the ETL and HTL, and observed a smaller possibility of carrier recombination and a shorter injection lifetime in the perovskite solar cell doubly modified with carrier transport layers, resulting in an enhancement of the PCE. The PCE reached 16% for a planar inverted perovskite device featuring an ETL incorporating 0.5 wt% Bphen within PC61BM and 0.1 wt% MoS2 within PEDOT:PSS; this PCE is more than 50% higher than the value of 10.2% for the corresponding control device.

Polyaniline modified graphene oxide (PANI/GO) composites were synthesized by dilute polymerization technique and were characterized by Fourier transformed infrared spectroscopy (FTIR), Raman spectroscopy, and scan- ning electron microscopy (SEM). The characterization results indicated that polyaniline molecules were successfully grafted on GO surfaces. The application of PANI/GO composites to the adsorption of heavy metals from aqueous solu- tions was investigated under ambient conditions. The maximum adsorption capacities of Co(II), Ni(II), Pb(II) and U(VI) ions on PANI/GO composites calculated from Langmuir models are 22.28, 25.67, 65.40 and 1552.31 mg/g, respec- tively. The excellent adsorption capacity suggests that PANI/GO composites can be applied as a promising adsorbent in heavy metal pollution cleanup in environmental pollution management.

The thermal reaction of C

The facile one-step reaction of [60]fullerene with aldehydes and primary amines in the presence of cheap and easily available Cu(OAc)

In this work, we demonstrated a viable experimental scheme for in-situ probing the effects of Au nanoparticles (NPs) incorporation on plasmonic energy transfer in Cu(In, Ga)Se2 (CIGS) solar cells by elaborately analyzing the lifetimes and zero moment for hot carrier relaxation with ultrabroadband femtosecond pump-probe spectroscopy. The signals of enhanced photobleach (PB) and waned photoinduced absorption (PIA) attributable to surface plasmon resonance (SPR) of Au NPs were in-situ probed in transient differential absorption spectra. The results suggested that substantial carriers can be excited from ground state to lower excitation energy levels, which can reach thermalization much faster with the existence of SPR. Thus, direct electron transfer (DET) could be implemented to enhance the photocurrent of CIGS solar cells. Furthermore, based on the extracted hot carrier lifetimes, it was confirmed that the improved electrical transport might have been resulted primarily from the reduction in the surface recombination of photoinduced carriers through enhanced local electromagnetic field (LEMF). Finally, theoretical calculation for resonant energy transfer (RET)-induced enhancement in the probability of exciting electron-hole pairs was conducted and the results agreed well with the enhanced PB peak of transient differential absorption in plasmonic CIGS film. These results indicate that plasmonic energy transfer is a viable approach to boost high-efficiency CIGS solar cells.

Measurements of reaction cross section (sigma(R)) for some proton-rich nuclei (N = 8, 10, 12 isotones) on carbon target at intermediate energies have been performed on RIBLL of HIRFL by a transmission method. The experimental sigma(R) values for Al-23 and P-27 are abnormally large compared with its neighboring nuclei and that of F-17 has an enhancement compared with neighboring isotopes. The calculation of relativistic density-dependent Hartree (RDDH) approach shows there is proton-halo structure in Al-23 and P-27 and there is a proton-skin in F-17. The significance of these measurements was discussed.

Radioactive ion beam line in Lanzhou (RIBLL) has been constructed for the production of short-lived radioactive nuclei and studies of exotic nuclei far from the β-stability line. It has been put into operation recently at the National Laboratory of Heavy Ion Accelerator Lanzhou. RIBLL consists of two doubly achromatic parts with a solid acceptance ΔΩ⩾6.5 msr, momentum acceptance Δp/p=±5% and maximum magnetic rigidityBp max=4.2 Tm. The second part of RIBLL serving as a spectrometer gives an element resolutionZ/ΔZ>150 and mass resolutionA/ΔA>300. The polarized secondary beams can be obtained by using a swinger dipole magnet to change the incident direction of primary projectile from 0° to 5°. The shortest lift time for secondary beams on RIBLL is less than 1 μs. First experiments were performed with neutron rich nuclei for understanding the properties of halo nuclei and exotic nuclear reactions.

To observe the impacts of doxapram on anesthetic efficacy and respiratory and circulatory functions during anesthesia with remifentanil given by target-controlled infusion (TCI) combined with propofol in painless artificial abortion.A total of 120 ASA I women requiring voluntarily painless artificial abortion were randomized into two equal groups. One group was given remifentanil by TCI at 2 ng/ml and propofol 1mg/kg (group I), and the other given remifentanil by TCI, propofol, and doxapram 0.6 mg/kg (group II). The anesthetic efficacy and respiratory and circulatory suppression during anesthesia were observed.Both of the two groups showed satisfactory anesthetic efficacy with comparable the BIS values (P0.05). No significant difference was noted in the induction time and awaking time between the two groups (P0.05), but group I had more serious respiratory and circulatory depression than group II (P0.05).Doxapram may attenuate respiratory and circulatory depression during anesthesia with remifentanil given by TCI combined with propofol in painless artificial abortion, and provide comparable anesthetic efficacy.