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BackgroundGlucose fluctuations may be associated with myocardial fibrosis. This study aimed to investigate the underlying mechanisms of glucose fluctuation-related myocardial fibrosis.MethodsStreptozotocin (STZ)-injected type 1 diabetic rats were randomized to five groups: the controlled blood glucose (CBG) group, uncontrolled blood glucose (UBG) group, fluctuated blood glucose (FBG) group, FBG rats injected with 0.9% sodium chloride (NaCl) (FBG + NaCl) group, and FBG rats injected with MCC950 (FBG + MCC950) group. Eight weeks later, left ventricular function was evaluated by echocardiography and myocardial fibrosis was observed by Masson trichrome staining. The primary neonatal rat cardiac fibroblasts were cultured with different concentrations of glucose in vitro.ResultsThe left ventricular function was impaired and myocardial fibrosis was aggravated most significantly in the FBG group compared with the CBG and UBG groups. The levels of interleukin (IL)-1β, IL-18, transforming growth factor-β1 (TGF-β1), collagen type 1 (collagen I), nuclear factor (NF)-κB, and nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome were significantly increased in the FBG group. In vitro, the inhibition of NF-κB and inflammasome reversed these effects. In vivo, NLRP3 inhibition with MCC950 reversed left ventricular systolic dysfunction and myocardial fibrosis induced by glucose fluctuations.ConclusionGlucose fluctuations promote diabetic myocardial fibrosis by the NF-κB-mediated inflammasome activation.

Background Modern industrial facilities urgently need effective wireless communication technology to monitor instruments and equipment, but electromagnetic interference and physical shielding often exist in these fields, thereby preventing traditional communication methods from working correctly. Objective As a special wireless optical communication technology, X-ray communication (XCOM) is expected to solve the problem of signal transmission under this extreme condition. Our goal was to prove the feasibility of XCOM for signal transmission under metal barrier condition. Methods The Monte Carlo method was used to simulate the transmission characteristics of X-ray beam under metal barrier conditions, and the communication performance of XCOM was evaluated. Moreover, the experimental demonstration system of XCOM was developed to test the penetration and communication performance of XCOM under metal shield. Results X-ray with energy above 150 keV could achieve a bit error rate of less than 10-4 after passing through a 20 mm iron, whereas X-ray with energy above 250 keV could maintain excellent communication performance after passing through a 30 mm iron. The experimental test results were consistent with the theoretical calculation. Conclusions As a new wireless optical communication technology, X-ray communication is expected to solve the problem of signal transmission under physical shielding conditions.

X-ray communication (XCOM) is an advanced space-communication technology. The high penetration of X-ray enables XCOM to achieve lower signal attenuation than conventional optical communication in Martian dust storm. This study provided a demonstration of this approach based on simulation methods. The transmission properties of X-ray beams in Martian non-dust storm weather were evaluated based on the MCNP5 code. Results demonstrated that the X-ray beam can transmit through a long-distance in Martian atmosphere. Moreover, on the basis of the anomalous diffraction and Mie theory codes, the transmission properties of X-ray and optical links in Martian dust storm were evaluated. Results showed that the dust attenuation of the X-ray links were significantly lower than that of optical links. Moreover, the penetration and communication performance of X-ray links were evaluated and compared with the optical link, considering atmospheric and dust attenuation. Results indicated that XCOM can be used to establish a low-BER communication link between rovers, and from the rover to the orbiter, in Martian dust storm.

As a vital component of the forest ecosystem, dead wood plays an important role in forest regeneration, species variety, water conservation, soil erosion avoidance, and the carbon cycle. At the moment, dead wood research is mostly concerned with the storage of dead wood in forests and the change of nutritional components throughout the decomposition process. There have been few investigations on the changes in soil active organic carbon components and bacterial community structure during the breakdown of dead wood. To investigate the impact of dead wood on soil active organic carbon components and the structure of microbial communities. we selected the soil under three different decay grades of Castanopsis eyrei dead wood and the forest soil without dead wood as the control. The basic physical and chemical indexes of soil, the composition of soil active organic carbon and the structure of microbial community were measured. Compared with the control group, dead wood mulching significantly increased the content of soil organic carbon and total nitrogen (P ), and dead wood significantly affected the content of soil active organic carbon (P ). The easily oxidized organic carbon, microbial biomass carbon and organic carbon under the severe decay dead wood were significantly higher than those in the control (P ), and the content of activated carbon increased with the increase of decay grade. The relative abundance of Actinobacteria, Chloroflexi, WPS-2, Patescibacteria and Bacteroidetes increased with the increase of decay grade of dead wood, and the relative abundance of soil bacteria under dead wood was higher than that of the control. Through the redundancy analysis of environmental factors and soil microbial community, we found soil total nitrogen and pH are the key factors driving microbial community. The distribution of soil bacterial community under light rotten dead wood is similar to that soil without dead wood, which is significantly different from that under moderate and severe rotten dead wood. The abundance of soil bacterial community and soil active organic carbon components are most affected by heavy rotten dead wood. Soil active organic carbon was significantly negatively correlated with Acidobacteria(P ), and positively correlated with Ktedonobacteria, Bacteroidia, Saccharimonadia and TK10(P ). The above research results show that dead wood has a great impact on soil physical and chemical properties and microbial community structure. Our study improves the impact of dead wood on soil activated carbon components and microbial community, and provides a theoretical basis for sustainable forest management.

Neuroscientists have emphasized visceral influences on consciousness and attention, but the potential neurophysiological pathways remain under exploration. Here, we found two neurophysiological pathways of heart-brain interaction based on the relationship between oxygen-transport by red blood cells (RBCs) and consciousness/attention. To this end, we collected a dataset based on the routine physical examination, the breaking continuous flash suppression (b-CFS) paradigm, and an attention network test (ANT) in 140 immigrants under the hypoxic Tibetan environment. We combined electroencephalography and multilevel mediation analysis to investigate the relationship between RBC properties and consciousness/attention. The results showed that RBC function, via two independent neurophysiological pathways, not only triggered interoceptive re-representations in the insula and awareness connected to orienting attention but also induced an immune response corresponding to consciousness and executive control. Importantly, consciousness played a fundamental role in executive function which might be associated with the level of perceived stress. These results indicated the important role of oxygen-transport in heart-brain interactions, in which the related stress response affected consciousness and executive control. The findings provide new insights into the neurophysiological schema of heart-brain interactions.

Glucose fluctuations may be associated with myocardial fibrosis. This study aimed to investigate the underlying mechanisms of glucose fluctuation-related myocardial fibrosis.Streptozotocin (STZ)-injected type 1 diabetic rats were randomized to five groups: the controlled blood glucose (CBG) group, uncontrolled blood glucose (UBG) group, fluctuated blood glucose (FBG) group, FBG rats injected with 0.9% sodium chloride (NaCl) (FBG + NaCl) group, and FBG rats injected with MCC950 (FBG + MCC950) group. Eight weeks later, left ventricular function was evaluated by echocardiography and myocardial fibrosis was observed by Masson trichrome staining. The primary neonatal rat cardiac fibroblasts were cultured with different concentrations of glucoseThe left ventricular function was impaired and myocardial fibrosis was aggravated most significantly in the FBG group compared with the CBG and UBG groups. The levels of interleukin (IL)-1β, IL-18, transforming growth factor-β1 (TGF-β1), collagen type 1 (collagen I), nuclear factor (NF)-κB, and nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome were significantly increased in the FBG group.Glucose fluctuations promote diabetic myocardial fibrosis by the NF-κB-mediated inflammasome activation.

The rapid growth and expansion ofCryptomeria japonica (Thunb. ex L. f.) D. Don in karst area strongly affects plant composition of native deciduous broad-leaved forest, which seriously threat ecosystem function and service. Given the importance of soil microorganisms in regulating nutrients cycling and plant species coexistence, understanding soil microbial attributes and their relationships with soil and vegetation features in forests harboring different C. japonica abundance will help understanding the drivers of ecosystem function changes. Here we examined the diversity and composition of soil bacterial and fungal communities and their correlations with plant diversity as well as soil physicochemical properties in karst broad-leaved forests with different relative abundances of C. japonica (i.e., a high, moderate, low and no proportion level with a stem density of 1,487, 538, 156 and 0 plant/hm2, respectively) in Mid-Subtropical China. We found that soil pH decreased while soil water content (SWC), total nitrogen (TN), total phosphorus (TP) and total potassium (TK) tended to increase with the increase in C. japonica abundance. In contrast, soil available nitrogen (AN), available phosphorus (AP) and available potassium (AK) content declined by 26.1%∼49.3% under the high level of C. japonica abundance. A gradual decrease in relative abundance of Acidobacteria and Chloroflexi while a pronounced increase in relative abundance of Ascomycota and Basidiomycota were observed with increase of C. japonica abundance. Alternations in bacterial composition were closely related to changes in AP and AK, while the change of fungal structure was mainly related to SWC, soil organic carbon (SOC) and pH, indicating that bacterial community was sensitive to declines in soil available nutrients and fungal structure was sensitive to changes in soil physicochemical properties (i.e., pH and SWC) and organic carbon resource. Understory plants had the highest α-diversity in forest containing moderate abundance of C. japonica, which might be related to the high bacterial diversity. Our findings suggest conservation of soil bacterial and fungal taxa that are responsible for nutrients availability and carbon sequestration is of great significance for improving the resistance of natural deciduous broad-leaved forests to the rapid spread of C. japonica in karst areas. Moreover, Acidobacteria, Chloroflexi, Ascomycota and Basidiomycota are potential indicators for soil properties changes, which should be taken into consideration in karst forest managements.

In order to understand the levels of indoor air pollution and health risks in public places, our research group conducted air quality monitoring and human health risk assessments for five types of public places (offices, classrooms, laboratories, banks, and hospitals) in Xi'an City from December 2017 to July 2020. The test items included formaldehyde, benzene, toluene, xylene

Background Growth in insect pest populations poses a significant threat to ecosystem functions and services, societal development, and food security in alpine regions under climate change. Risk assessments are important prioritization tools for pest management, which must be used to study insect pest expansion in alpine ecosystems under global warming. We used species distribution modeling to simulate the current and future distribution probabilities of 58 insect pest species in the Qinghai Province, China, based on a comprehensive field investigation. Subsequently, general linear modeling was used to explore the relationship between the distribution probability of these species and the damage caused by them. Finally, we assessed the ecological risk of insect pest expansion across different alpine ecosystems under climate change. Results Climate change could increase the distribution probabilities of insect pest species across different alpine ecosystems. However, the presence of insect pest species may not correspond to the damage occurrence in alpine ecosystems based on percent leaf loss, amount of stunting, and seedling death of their host species. Significant positive relationships between distribution probability and damage occurrence were found for several of the examined insect pest species. Insect pest expansion is likely to increase extensively in alpine ecosystems under increasing carbon dioxide (CO2 ) emission scenarios. Conclusion The relationships between distribution probability and damage occurrence should be considered in species distribution modeling for risk assessment of insect pest expansion under climate change. Our study could improve the effectiveness of risk assessment of insect pest expansion under changing climate conditions. © 2021 Society of Chemical Industry.

Enhancing the positional information acquisition during Mars entry blackout improves the Mars landing mission reliability. A positioning method based on the high-penetration of X-rays was developed to solve the problem. The X-ray signal attenuation was estimated. The positioning performance and the influence of X-ray signal transmission system were also evaluated. Results indicated that the X-ray signal attenuation is extremely low, and the X-ray-based method is expected to be a potential application for obtaining high-precision positional information during Mars entry blackout.

The principle of detecting the vacuum degree of terahertz wave is discussed. The imaging principle, imaging characteristics, imaging speed, and price of pulsed terahertz and continuous wave terahertz are compared and analyzed. The conclusion shows that the pulse terahertz frequency is higher in the practicality of vacuum detection, but it is expensive, bulky and inconvenient to operate in the field. Continuous wave terahertz imaging has high frequency resolution, low price, short imaging time and practical more sexual.

A three-core photonic crystal fiber (PCF) surface plasmon resonance (SPR) biosensor with high performance is presented. The structure of the biosensor is easy to implement and has good repetition. The outer layer of the fiber structure is gold film. The analyte is placed on the surface of the gold film. The Full vector finite element method is used to numerical simulation and analysis the transmission mode and characteristics of the three-core PCF-SPR biosensor. The influence of sensor structure parameters on sensing performance is investigated. The structure parameters are optimized. The optimum structure parameters are given. The refractive index (RI) sensitivity of the sensor is discussed there. The results show that the average refractive index sensitivity of the sensor is 3435 nm/RIU in the sensing range of 1.33–1.40, and the resolution is 2.91 × 10−6 RIU. The sensor has the advantages of high sensitivity and high resolution. And it can be applied to real-time detection of the biomolecules and small drug-molecules.

Rhizosphere microbial community structure and composition are affected by tree species, soil properties and fine root parameters. In this study, we investigated the changes in rhizosphere soil properties, fine root parameters and rhizosphere microbial community composition following Robinia pseudoacacia afforestation. Rhizosphere microorganisms were analyzed by high-throughput sequencing of the 16S rRNA gene and the internal transcribed spacer (ITS). Soil available phosphorus (AP) and fine root total phosphorus (RTP) were lower at the 25- and 35-Y sites than at the 5- and 15-Y sites, and fine root parameters could be inferred by soil AP, nitrate nitrogen (NO3−) and nitrogen:phosphorus (N:P). Rhizosphere microbial community composition clustered into the 5- and 15-Y group and the 25- and 35-Y group at the operational taxonomic unit (OTU) level. At genus level, 28.57% of the major bacterial genera (relative genera abundances ≥0.1%) and 18.33% of the major fungal genera exhibited significant differences. Rhizosphere soil and fine root properties explained 89.42% and 65.04% of the total variation in the major bacterial genera group, and 84.17% and 62.13% of the total variation in the major fungal genera group at the genus level, respectively. Soil AP and fine root TP are crucial for regulating rhizosphere soil microbial communities. Our results suggest that fine root and soil properties cooperatively affect rhizosphere microbial community composition in the root-soil system following Robinia afforestation.

A D-shaped photonic crystal fiber surface plasmon resonance biosensor is presented with high sensitivity. Determinand are used outside the fiber structure to realize a simple detection mechanism. The sensor consists of photonic crystal fiber, graphene and metal. The sensitivity of the sensor is enhanced by graphene between the silver layer and D-shaped photonic crystal fiber. The two small air holes in the center of the photonic crystal fiber are beneficial to the phase matching of the core and the plasmon polaritons. The two large air holes are beneficial to the birefringence and the coupling of polarized light with metal. The Full vector finite element method is used to numerical simulation and analysis the transmission mode and characteristics of the photonic crystal fiber surface plasmon resonance biosensor. In the range of refractive index is 1.34–1.40, the average sensitivity of the sensor is 4850 nm/RIU with a high resolution of 2 × 10−5RIU. The minimum full width at half maximum is 10 nm. The proposed sensor can be applied to real-time detection of the biomolecules and small drug-molecules due to the advantages of long distance transmission, high sensitivity and high resolution.

Thinning can effectively improve forest production and maintain ecological stability. However, the changes in soil microbial community compositions after thinning are still not well understood. In this study, we investigated the changes in the soil microbial community of mature Chinese pine (Pinus tabuliformis) plantations in the Loess Plateau after 11 years of four different thinning intensity treatments. Furthermore, the responses of the soil microbial community to changes in understory plants and soil properties were analyzed. The ratios of wood removal investigated were 0 (CK), 15% (LIT), 30% (MIT) and 45% (HIT). Compared with the CK, thinning significantly increased the Shannon index, species richness, coverage and biomass of the understory plants, and these values were highest for the HIT. The soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), nitrate nitrogen (NO3−-N) and available phosphorus (AP) concentrations increased with increasing thinning intensity. Thinning intensity did not significantly affect soil microbial community diversity indices. With respect to the dominant bacterial groups, the relative abundance of Proteobacteria was much higher in the HIT, while that of Acidobacteria was much higher in the LIT and CK. For the dominant fungal groups, the relative abundance of Basidiomycota was lowest in the HIT, while that of Ascomycota was highest in the same treatment. Redundancy analysis (RDA) showed that SOC, TN, and AP significantly correlated with soil bacterial communities and that SOC, TN, TP, AP and NO3−-N significantly correlated with soil fungal communities. The understory vegetation influenced soil fungal communities rather than soil bacterial communities. These findings suggest that the aboveground vegetation diversity and soil nutrients were improved with the increased thinning intensity after 11 years. The copiotrophic groups (e.g. Proteobacteria) and oligotrophic groups (e.g. Acidobacteria) differed significantly among the four thinning treatments, indicating a dependence of the soil microbial community composition on soil nutrients.

In view of the demand for high-energy and high-bandwidth signal detection in X-ray communication (XCOM) during spacecraft reentry blackout, a detection module using fast-decay LYSO scintillator coupled with Silicon photomultiplier (SiPM) was proposed in this study. The theoretical model based on the Monte Carlo simulation and Personick’ theory was established and the detector prototype was built. Moreover, the signal to noise ratio (SNR) and bit error rate (BER) performance were investigated. Results present that the SNR of 19.8 dB, 29.9 dB and 35.5 dB could be reached for X-ray with the energy of 17 keV, 59.5 keV and 122 keV respectively. This energy response characteristic is much suitable for the X-ray signal detection during spacecraft reentry blackout. Additionally, the deviation of SNR corresponding to the BER between the theoretical and experimental results does not exceed 0.3 dB when the data rate is 100 kbps, which proves the validity of the theoretical model. Furthermore, the numerical analysis shows that the scheme demonstrates high SNR and low BER performance in high bandwidth and low signal receiving power, which explains the superiorities in X-ray signal detection of the design. This work provides the theoretical basis and design reference for the LYSO–SiPM X-ray signal detection module.