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Superlenses made of plasmonic materials and metamaterials have been exploited to image features of sub-diffractional scale. However, their intrinsic losses impose a serious restriction on the imaging resolution, which is a long-standing problem that has hindered wide-spread applications of superlenses. Optical waves of complex frequency exhibiting a temporally attenuating behavior have been proposed to offset the intrinsic losses in superlenses via virtual gain, but the experimental realization has been missing due to the challenge involved in preparing the illumination with temporal decay. Here, by employing multi-frequency measurement, we successfully implement a synthetic optical wave of complex frequency to experimentally observe deep-subwavelength superimaging patterns enabled by the virtual gain. Our work represents a practical approach to overcoming the intrinsic losses of plasmonic systems for imaging and sensing applications., Comment: 17 pages, 3 figures

Scripts used for "Molecular and cellular evolution of the primate dorsolateral prefrontal cortex".&nbsp

Additional file 1: Fig. S1. The chemical structure of (A) cholesterol and (B) Rg3. Fig. S2. The size distribution of the Nanoxel-PM. Fig. S3. The size stability of the C-Lp/DTX and Rg3-Lp/DTX. Fig. S4. The quantitative analysis of cellular uptake of C-Lp/C6, Rg3-Lp/C6 and Rg3-Lp/C6 with GLUTs inhibitors in 4T1 cells via flow cytometry. Fig. S5. Confocal laser scanning microscope (CLSM) images of the cellular uptake of C-Lp/C6, Rg3-Lp/C6 and Rg3-Lp/C6 with GLUT1 inhibitors in 4T1 cells. Scale bars: 20 μm. Fig. S6. Ex vivo imaging (A) and ROI values (B) of excised organs 24 h after injection. Fig. S7. Ratio of organ weight to body weight in 4T1-bearing mice at the end point of the treatment. n = 6 in each group. Fig. S8. Blood hematology tests were performed in tumor bearing mice with different treatment. Fig. S9. Quantitative western blot analysis of the level of p-Smad2/3 and α-SMA in 3T3 after different treatments. Fig. S10. Quantitative western blot analysis of the level of p-Smad2/3 and α-SMA in tumor tissues after different treatments. Fig. S11. Flow cytometry analysis of activated CAFs in tumor after treatment with PBS, DTX, C-Lp/DTX, Nanoxel-PM, Rg3, Rg3-Lp, Rg3/DTX and Rg3-Lp/DTX, respectively. Fig. S12. Representative gating strategy used for flow cytometry analysis of CD4+ T cells, CD8+ T cells, MDSC (CD11b+Gr1+), M1 macrophages (F4/80+CD86+), M2 macrophages (F4/80+CD206+), and Treg cells (CD4+Foxp3+) in the tumors (gated on CD45+ cells) after different treatments. Fig. S13. Flow cytometric and histogram analysis of M1-type and M2-type macrophages after different treatment. Fig. S14. Analysis of the level of collagens in tumors treated with PBS and different DTX formulations. Fig. S15. H&E staining of major organs.

Seeking the criterion for diagnosing topological phases in real materials has been one of the major tasks in topological physics. Currently, bulk-boundary correspondence based on spectral measurements of in gap topological boundary states and the fractional corner anomaly derived from the measurement of the fractional spectral charge are two main approaches to characterize topologically insulating phases. However, these two methods require a complete band-gap with either in-gap states or strict spatial symmetry of the overall sample which significantly limits their applications to more generalized cases. Here we propose and demonstrate an approach to link the non-trivial hierarchical bulk topology to the multidimensional partition of local-density of states (LDOS) respectively, denoted as the bulk-LDOS correspondence. Specifically, in a finite-size topologically nontrivial photonic crystal, we observe that the distribution of LDOS is divided into three partitioned regions of the sample - the two-dimensional interior bulk area (avoiding edge and corner areas), one-dimensional edge region (avoiding the corner area), and zero-dimensional corner sites. In contrast, the LDOS is distributed across the entire two-dimensional bulk area across the whole spectrum for the topologically trivial cases. Moreover, we present the universality of this criterion by validating this correspondence in both a higher-order topological insulator without a complete band gap and with disorders. Our findings provide a general way to distinguish topological insulators and unveil the unexplored features of topological directional band-gap materials without in-gap states.

First published: 15 September 2019 https://doi.org/10.1002/lpor.201900164

A mesoporous silica loaded with molybdenum phosphide nanoparticles (MoP@MSN) was synthesized using Pluronic F-127 as a hard template. Using the method of XRD and HRTEM, the crystallinity, the phase structure, and the morphologies of the MoP@MSN were investigated. The results showed that the MoP@MSN were composed of nanoflakes with approximately 100 nm. Through the linear sweep voltammetry (LSV), the Tafel slopes of 100 and 341 mV were yielded for MoP@MSN and pure MoP, respectively, meaning that the composite of MSN can significantly improve the conductivity of the products. Meanwhile, the mesoporous MoP@MSN presented excellent electrochemical activity and stability toward hydrogen evolution compared with those of bulk MoP nanoparticles, showing a promising prospect in hydrogen production.

Experimental equipment that can provide suitable acceleration peaks (APs) and acceleration pulse widths (AWs) is required for impact studies. It is necessary to design suitable structures and select appropriate materials of the impact pair for experimental equipment. To propose the control strategies of the AP and AW, the effects of the material properties and geometric parameters of the impact pair on the contact acceleration during low-velocity impacts were investigated. The density ρ1 and velocity v of the projectile, and the elastic modulus E2 and yield strength A2 of the target were the dominant factors affecting the AP. The ρ1, A2, and E2 were the primary factors influencing the AW. The AP increased with a decrease in the ρ1 and increases in the v and elastic modulus E1 of the projectile and the thickness H, E2, A2, strain-hardening constant B2, and strain-hardening index n2 of the target. The AW increased with the ρ1 and decreased with the H, E2, and A2. Based on the elastic stress wave and contact mechanics, the influences of the primary factors on the AP and AW were explained. The strategies proposed in this work agreed with the simulation results and the literature.

Dry spices are at risk of microbial contamination because traditional drying processes fail to eliminate unwanted microorganisms. Radiofrequency (RF) has shown the potential for pasteurizing agricultural products. To control the natural microflora, we added a decontamination step before hot-air drying for preparing Sichuan pepper. Sichuan pepper kernels were heated by RF to 50 °C (cold spot), held for 10 min, and dried in a hot-air convection oven at 50 °C for 10 h. The total plate counts (TPCs) and quality loss were traced and compared with those following a 50 °C hot-air drying process as the control group. RF heating and holding processes achieved reductions of 0.68 ± 0.52 and 1.63 ± 0.35 log CFU/g (dry base, d.b), respectively, in Sichuan pepper TPCs. The final products treated by RF had 2.45 ± 0.19 log CFU/g (d.b), whereas the TPC in the control group remained as high as 2.95 ± 0.20 log CFU/g (d.b). Sichuan pepper kernels in the two groups showed similar drying rates; however, RF-treated Sichuan pepper lost most of its oil droplets, resulting in significant reductions in flavor and color. The results indicated that RF-assisted hot-air drying could efficiently control the natural microflora of Sichuan pepper, but with severe quality deterioration.

Many key electromechanical parts and advanced electronics work in a impact-vibration compound environment. In order to better simulate the impact-vibration coupling test environment and truly reflect the performance parameters and failure mechanism, an integrated resonant cavity structure is designed. It can generate self-excited vibration loading under impact. The key component that affects the resonant signal is the properties of the resonant particles. These parameters are mainly the shape, size, and number of resonant particles. In order to study the influence of these parameters on the Self-excited resonance signal, Adams was used to simulate the impact processes. The overload curves of the impacted parts under different resonant particle properties were obtained. Studies have shown that using larger, larger numbers of cubic particles produces more obvious resonant signals. These signals have larger harmonic amplitudes and higher resonant frequencies. Thus, a set of resonant particle parameter values that can obtain a better resonant signal is designed.

This article designs and implements a pressure sensor intelligent system with temperature compensation, which is based on STM32F103RCT6 microcontroller. The system is used to measure accurate small range signals of pressure sensor. Designing the functional circuit makes the output of the system digitized. Utilizing the improved BP neural network algorithm compensates the digital signal of the pressure sensor to ensure the accuracy of the pressure sensor. The repeated test shows that the intelligent system compensates the temperature drift of low scale pressure sensor effectively and ensures the property and the measurement accuracy of the pressure sensor.

In view of the existing impact equipment can't meet the needs of continuous high speed impact experiment, a new type of high speed multiple impact experiment method is proposed and the principle of system design is also given. The experiment system is mainly composed of impact system, automatic feed system and the control system, Wherein the main components of the impact system is a horizontal turntable with a plurality of impact components evenly distributed on the edge of the turntable, convert the rotational kinetic energy into impact kinetic energy, apply high impact overload to the test component, when the turntable reaches the set speed, the automatic feed system feed the component to the experiment position in the designed window time, perform an impact experiment, the control system realizes the control of impact and automatic feed and return, also realizes the recovery of experiment data. On the basis of the completion of system design, a simulation model is established to verify the design, the simulation results show that the designed experiment system has the advantages of novel structure and superior performance, can realize high speed and heavy overload impact, of important scientific research significance and practical value.

Under the situation of increasing problems concerning with the environmental quality in forest land and the long-term productivity of forest,it was significant to develop and improve management strategies that maintain the function and protect the resources of soils.Changes of forest management strategies may lead to change in SOC quantity and quality.It was necessary to maintain a high SOC status for long-term land use due to the multiple beneficial effects of SOC on the soil nutrient states,structure and water holding capacity etc.The effects of different silvicultural practices on soil organic carbon were still poorly approached.Thus we performed the study on changes of soil organic carbon(SOC) in the Moso(Phyllostachys pubescens) stands among the long-term conversion of extensively managed and intensively managed in Fuyang County,Zhejiang province,where Moso were widely distributed.Bamboo stands of different management types,which were established in 1984,were designed to investigate the effects of intensive management on SOC.The results showed: total organic carbon(TOC),readily oxidation carbon(ROC),water soluble organic carbon(WSOC) and light fraction organic matter(LFOM) in 0—10cm soil layer were significantly decreased by 8.64%,14.11%,8.29% and 29.70%(0—20cm) respectively after intensive management.The vertical features of different soil organic carbon under two management types of bamboo stands were observed in decline trends with increasing of soil depths,while both of the decline scopes were different.The profile distribution of soil ROC and WSOC varied to some extent since intensive practice.These different fractions of labile organic carbon mentioned above were all interrelated,significantly or extremely significantly,and they also were well correlated with total N,hydrolysis N,available K,Ca,Mg(WSOC wasn′t significantly correlated with available P),while LFOM wasn′t significantly related to other soil nutrients except available Ca.Moreover after intensive management,availability of ROC,availability of WSOC and activity of carbon pool were decreased with significant level in part of soil layers.Therefore,to improve soil quality and achieve the goal of sustainable management of bamboo stands,a mixture of organic and inorganic manures with the proper ratio in bamboo stands should be applied under the conditions of intensive management,combined with ploughing,weeding,reasonable bamboo leaving and bamboo cutting,which could fulfill a high yield of bamboo shoot and bamboo culm,and maintain the ecological function of bamboo stands. The variation of results observed in soil C pool responded to different silvicultural methods in different studies may be due to variation in site types,original soil condition,timing and realization of forest managements,climatic factors,and/or interaction of some or all of these.However,this study along with the meta-analysis suggested that a categorical assumption of soil C loss under different forest management was unwarranted.Certainly,it was still needed to identify management methods that were most likely to cause or prevent SOC loss by further study.On the other hand,hydric soils may be much more sensitive to changes in temperature and moisture regimes as a result of silvicultural practices.Because the amount of the organic matter pool in mineral soils represents the potential to supply nitrogen,it is desirable to maintain organic matter in bamboo stands.

To improve the fuze-warhead coordination efficiency, the working principle of gun-launched electron-magnetic pulse bomb was analyzed, and the coordination process in actual ballistics was divided into two stages. Stage 1: the killing area model was built to analyze the optimum burst point, and by introducing damage parameters, this stages coordination efficiency was characterized by damage rate. Stage 2: the best initiation timing model was built, the timing error spreading was calculated using small deviation method, and the coordination efficiency was characterized by the degree of seed current closer to its maximum. Based on the analysis above, the calculation model of coordination efficiency was summarized, and some technical methods were given.