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Polyporus umbellatus is a traditional Chinese medicinal mushroom. The growth of P. umbellatus sclerotia requires the rhizomorphs of Armillaria spp. to supply nutrition. Whether the main components (MC) of sclerotia of P. umbellatus are related to the phylogeny of Armillaria associates or other environmental factors is largely unknown. In this study, we collected 17 sclerotia and soil samples from northeast to southwest China. In total, 17 Armillaria associates were isolated, and sclerotial MC contents and soil characteristics (total N, P, K, and organic matter) were determined. The analysis revealed that the MC content of P. umbellatus did not resemble a Brownian motion process in phylogeny of Armillaria associates, but were significantly influenced by the total N content of the soil. These results provide clear evidence that sclerotia of P. umbellatus associating with phylogenetic related Armillaria associates possess differing MC content. The mechanisms of nutrient exchange in P. umbellatus-Armillaria associations now require further elucidation.

Mycorrhizal fungi play an important role in the germination and growth of orchids essentially influencing their survival, abundance, and spatial distribution. In this study, we investigated the composition of the mycorrhizal fungal community in seven terrestrial orchid species inhabiting Song Mountain, Beijing, China, using Illumina MiSeq high-throughput sequencing. The mycorrhizal communities in the seven orchids were mainly composed of members of the Ceratobasidiaceae, Sebacinales, and Tulasnellaceae, while a number of ectomycorrhizal fungi belonging to the Russulaceae, Tricholomataceae, Thelephoraceae, and Cortinariaceae were occasionally observed. However, the dominant fungal associates and mycorrhizal community differed significantly among the orchid species as well as subhabitats. These findings confirm the previous observation that sympatric orchid species show different preferences for mycorrhizal fungi, which may drive niche partitioning and contribute to their co-occurrence.

Objective We performed this meta-analysis to determine which stent among everolimus eluting stents (EES), sirolimus eluting stents (SES) and paclitaxel eluting stents (PES) should be preferred for the treatment of DM patients. Methods A systematic search of publications about randomized controlled trials (RCTs) focused on diabetic patients received EES, SES or PES was conducted. We evaluated the following indicators: target vessel revascularization (TVR), target lesion revascularization (TLR), late luminal loss (LLL), stent thrombosis (ST), myocardial infarction (MI), all-cause mortality and cardiac mortality. Results EES showed obvious advantages over SES for DM patients, as it induced the lowest rate of target vessel revascularization and target lesion revascularization (TLR) (p = 0.04). In addition, EES induced lower in-segment LLL than PSE and SES and lower in-stent LLL than PES in DM patients (all p p = 0.04) and MI rates compared to PES (RR = 0.44, 95% CI: 0.26–0.73, p = 0.0002). Furthermore, EES could reduce the ST rate compared with both SES (RR = 0.53, 95% CI: 0.28–0.98, p = 0.04) and PES (RR = 0.18, 95% CI: 0.07–0.51, p = 0.001). Conclusion Among those three types of stents, EES should be the first recommended stent for DM patients.

A compact annular ring microstrip antenna was proposed for a wireless sensor network (WSN) application in the 2.4 GHz band. In this paper the major considerations of the conformal antenna design were the compact size and the impact on antenna’s performance of a steel installation base. By using a chip resistor of large resistance (120 Ω) the antenna size was reduced to 38% of that a conventional annular ring patch antenna. With the addition of the steel installation base the resonant frequency of the antenna increases about 4.2% and the bandwidth reduces from 17.5% to 11.7% by adjusting the load resistance simultaneously. Several key parameters were discussed and optimized, and the antenna was fabricated and its performance measured. The antenna is well matched at 2.4 GHz with 34.2 dB return loss and –2.5 dBi peak gain. Meanwhile, it exhibits excellent radiation patterns with very low cross-polarization levels.

The effects of a steel installation base on the proposed microstrip patch antenna are investigated. The models of the antenna with different surroundings are established in Ansoft HFSS software. The variations in antenna performances are compared in simulation and measurement, respectively. And Good agreements are achieved between the measured and simulated results. It is found that the resonant frequency is shifted upward by about 60MHz with the introduction of the steel base, while the matching level is decreased. Meanwhile, the VSWR 2:1 bandwidth is reduced by about 80MHz. The results indicate that the steel base has great influences on the antenna characteristics, and the simulation work provides powerful guidance for the antenna design.

The pressure measurement of an explosion is a key problem in the process of new type ammunition research. With the higher requirements for the measurement technology, the traditional cable-connecting measurement method is unsuitable for the development due to its inherent weakness. In this paper, a pressure measurement system based on the stored measurement theory is proposed for the explosion shock waves. An ICP pressure sensor is selected as the sensing element through the comparison of different sensors. According to the theory of stored measurement, the key circuits are designed effectively, such as signal conditioning circuit, signal sampling and storing circuit, controlling circuit, etc. The proposed system has been debugged and calibrated successfully, and the effectiveness and convenience have also been verified in actual explosion experiments.

The temperature measurement of an explosion is a key problem in weapon research area. The non-contact thermometry has been developed to relative maturity by now, but the accuracy of this method is limited by uncertainties in the emissivity determination. In this paper, a contact temperature measurement system is proposed based on a tungsten-rhenium thermocouple. The cold junction compensation of the thermocouple is solved by the method of temperature correction, and the linearization of the thermocouple is carried out by searching the reference table directly. Two calibrations for the thermocouple are implemented in laboratory, one is the static calibration by using a dry block calibrator, and the other is the response time calibration by means of a CO2 laser. And the calibration results show that the thermocouple is suitable for the explosion temperature measurement. The proposed system is designed according to the theory of stored measurement, and the effectiveness of the system is verified in actual explosion experiments.