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High-quality two-dimensional atomic layered p–n heterostructures are essential for high-performance integrated optoelectronics. The studies to date have been largely limited to exfoliated and restacked flakes, and the controlled growth of such heterostructures remains a significant challenge. Here we report the direct van der Waals epitaxial growth of large-scale WSe 2 /SnS 2 vertical bilayer p–n junctions on SiO 2 /Si substrates, with the lateral sizes reaching up to millimeter scale. Multi-electrode field-effect transistors have been integrated on a single heterostructure bilayer. Electrical transport measurements indicate that the field-effect transistors of the junction show an ultra-low off-state leakage current of 10 −14 A and a highest on–off ratio of up to 10 7 . Optoelectronic characterizations show prominent photoresponse, with a fast response time of 500 μs, faster than all the directly grown vertical 2D heterostructures. The direct growth of high-quality van der Waals junctions marks an important step toward high-performance integrated optoelectronic devices and systems. Growth of large area and defect-free two-dimensional semiconductor layers for high-performance p–n junction applications has been a great challenge. Yang et al. prepare millimeter-scaled WSe 2 /SnS 2 vertical heterojunctions by two-step van der Waals epitaxy, which show excellent optoelectronic properties.

Heart failure (HF) and atrial fibrillation (AF) are often coexisting. They have common risk factors and pathophysiologic mechanisms. Sacubitril/valsartan has shown efficacy and tolerability in patients with HF. Thus, the study was performed to evaluate the impact of sacubitril/valsartan on AF occurrence in patients with HF. The Embase and PubMed were searched from their inception date to June 2021 for all relevant randomized controlled trials (RCTs) evaluating the efficacy of sacubitril/valsartan in HF. The outcome of interest was the AF occurrence during the follow-up. Relative risks (RRs) with 95% confidence intervals (CIs) were pooled using a random-effects model. Six trials involving a total of 15,512 patients were included (7,750 randomized to sacubitril/valsartan and 7,762 to control). All trials were randomized, double-blind, and active-control. There was no significant difference in the prevention of AF occurrence between the sacubitril/valsartan group and the control group (enalapril or valsartan) in patients with HF (RR 1.07, 95%CI 0.95 to 1.19; I2 4%). Sacubitril/valsartan was similar to either enalapril or valsartan in preventing the occurrence of AF in patients with HF.

We investigate the ability of phase-sensitive amplification (PSA) to noiselessly amplify the preferred quadrature components of single-photon signals that are limited by phase fluctuations relative to the pump. We present a PSA enhancement strategy that is more realistic for possible experimental realization and is expected to significantly improve the detection of weak signals at the single-photon level and obtain more useful information. Our study shows that with a large PSA gain, proper transmissivity allows both direct and balanced homodyne detections to operate optimally simultaneously, and effectively improves the noise figure degradation owing to the internal losses and non-ideal detection efficiency.

As an important mid-infrared to far-infrared optical window, ZnS is extremely important to improve spectral transmission performance, especially in the military field. However, on account of the Fresnel reflection at the interface between the air and the high-strength substrate, surface optical loss occurs in the ZnS optical window. In this study, the concave antireflective sub-wavelength structures (ASS) on ZnS have been experimentally investigated to obtain high transmittance in the far-infrared spectral range from 6 μm to 10 μm. We proposed a simple method to fabricate microhole array ASS by femtosecond Bessel beam, which further increased the depth of the microholes and suppressed the thermal effects effectively, including the crack and recast layer of the microhole. The influence of different Gaussian and Bessel beam parameters on the microhole morphology were explored, and three ASS structures with different periods were prepared by the optimized Bessel parameters. Ultimately, the average transmittance of the sample with the ASS microhole array period of 2.6 μm increased by 4.1% in the 6 μm to 10 μm waveband, and the transmittance was increased by 5.7% at wavelength of 7.2 μm.

In the present study, 3 replanted black pepper orchards with continuously cropping histories for 10, 21, and 55 years in tropical China, were selected for investigating the effect of monoculture on soil physiochemical properties, enzyme activities, bacterial abundance, and bacterial community structures. Results showed long-term continuous cropping led to a significant decline in soil pH, organic matter contents, enzymatic activities, and resulted in a decrease in soil bacterial abundance. 454 pyrosequencing analysis of 16S rRNA genes revealed that the Acidobacteria and Proteobacteria were the main phyla in the replanted black pepper orchard soils, comprising up to 73.82% of the total sequences; the relative abundances of Bacteroidetes and Firmicutes phyla decreased with long-term continuous cropping; and at genus level, the Pseudomonas abundance significantly depleted after 21 years continuous cropping. In addition, bacterial diversity significantly decreased after 55 years black pepper continuous cropping; obvious variations for community structures across the 3 time-scale replanted black pepper orchards were observed, suggesting monoculture duration was the major determinant for bacterial community structure. Overall, continuous cropping during black pepper cultivation led to a significant decline in soil pH, organic matter contents, enzymatic activities, resulted a decrease in soil bacterial abundance, and altered soil microbial community membership and structure, which in turn resulted in black pepper poor growth in the continuous cropping system.

Soil organisms are affected by the presence of predatory protists. However, it remains poorly understood how predatory protists can affect plant disease incidence and how fertilization regimes can affect these interactions. Here, we characterise the rhizosphere bacteria, fungi and protists over eleven growing seasons of tomato planting under three fertilization regimes, i.e conventional, organic and bioorganic, and with different bacterial wilt disease incidence levels. We find that predatory protists are negatively associated with disease incidence, especially two ciliophoran Colpoda OTUs, and that bioorganic fertilization enhances the abundance of predatory protists. In glasshouse experiments we find that the predatory protist Colpoda influences disease incidence by directly consuming pathogens and indirectly increasing the presence of pathogen-suppressive microorganisms in the soil. Together, we demonstrate that predatory protists reduce bacterial wilt disease incidence in tomato plants via direct and indirect reductions of pathogens. Our study provides insights on the role that predatory protists play in plant disease, which could be used to design more sustainable agricultural practices. Soil organisms are affected by the presence of predatory protists. Here, the authors predatory protists are negatively associated with bacteria wilt disease incidence in tomato plants and that fertilisation enhances the abundance of predatory protists

Let (Xi,di) be a compact metric space with metric di, i=1,2…,k, and G be a discrete infinitely countable amenable group. This paper is based on continuous actions G↷Xi on compact metric spaces (Xi,di). Firstly, we introduce the concept of weighted Bowen balls, and then use the concept of weighted Bowen balls to introduce the corresponding lower (upper) weighted local entropy, as well as propose the concept of weighted Bowen topological entropy defined in terms of Hausdorff dimension by weighted Bowen balls, and prove Billingsley-type theorem between these two types of entropies by using the equivalent definition of weighted Bowen topological entropy.

Background Microbiomes play vital roles in plant health and performance, and the development of plant beneficial microbiomes can be steered by organic fertilizer inputs. Especially well-studied are fertilizer-induced changes on bacteria and fungi and how changes in these groups alter plant performance. However, impacts on protist communities, including their trophic interactions within the microbiome and consequences on plant performance remain largely unknown. Here, we tracked the entire microbiome, including bacteria, fungi, and protists, over six growing seasons of cucumber under different fertilization regimes (conventional, organic, and Trichoderma bio-organic fertilization) and linked microbial data to plant yield to identify plant growth-promoting microbes. Results Yields were higher in the (bio-)organic fertilization treatments. Soil abiotic conditions were altered by the fertilization regime, with the prominent effects coming from the (bio-)organic fertilization treatments. Those treatments also led to the pronounced shifts in protistan communities, especially microbivorous cercozoan protists. We found positive correlations of these protists with plant yield and the density of potentially plant-beneficial microorganisms. We further explored the mechanistic ramifications of these relationships via greenhouse experiments, showing that cercozoan protists can positively impact plant growth, potentially via interactions with plant-beneficial microorganisms including Trichoderma, the biological agent delivered by the bio-fertilizer. Conclusions We show that protists may play central roles in stimulating plant performance through microbiome interactions. Future agricultural practices might aim to specifically enhance plant beneficial protists or apply those protists as novel, sustainable biofertilizers. 9YGnSNgqaHj2gH_1N6en5w Video abstract

The continuous extraction of mining resources has led to the destruction of landscape space, which has had a great impact on the human living environment and pristine ecosystems. Optimizing the ecological spatial networks of mining areas can restore and enhance the damaged ecological environment. However, there are few cases of ecological spatial network optimization in mining areas, and there are still some shortcomings. Therefore, in this study, we propose an ecological spatial network theory and a synergistic enhancement of ecological functions and carbon sink optimization model (SEEC) for urban restoration in mining areas, emphasizing the functional and carbon sink nature of ecological sources. We selected a typical mining area in Xuzhou City as the study area, explored the changes in the nature and function of the ecological spatial network from 2000 to 2020, and selected the ecological spatial network in the mining area of Xuzhou City in 2020 as the optimization study case, adding 27 ecological stepping stones and 72 ecological corridors. Through the comparison of robustness before and after optimization, we found that the optimized ecological spatial network has a stronger stability and ecological restoration ability. This study provides strategies and methods for ecological restoration projects in national mining cities and also provides references and lessons for ecological restoration in other mining areas in the future.

Background Ventilator-associated pneumonia (VAP) is a severe infection among patients in the neurosurgery intensive care unit (NICU). Methods We retrospectively evaluated risk factors for early-onset ventilator-associated pneumonia (EOVAP) from January 2019 to December 2019 at a NICU. A total of 89 NICU patients who were intubated within 48 h of onset and whose mechanical ventilation time was at least 7 days were enrolled. We evaluated EOVAP that occurred within the first 7 days after the onset of mechanical ventilation. The enrolled patients had no history of chronic lung disease and no clinical manifestations of infection before intubation. Clinical data of patients were recorded, and the incidence of and risk factors for EOVAP were analyzed. Patients were also grouped by age (≥ 65 vs. < 65 years) and whether they had received hypothermia treatment or not. Results Among 89 mechanically ventilated patients (49 men and 40 women; the mean age ± SD was 60.1 ± 14.3 years), 40 patients (44.9%) developed EOVAP within 7 days and 14 patients (15.7%) had a multidrug resistant bacterial infection. Binary logistic regression analysis indicated that older age (≥ 65 years) (odds ratio [OR]:3.53, 95% confidence interval [CI]:1.27–9.79, P = 0.015) and therapeutic hypothermia (OR:3.68, CI:1.10–12.31, p = 0.034) were independent predictors of EOVAP. Levels of peripheral blood leukocytes, neutrophils and platelets were lower in the therapeutic hypothermia group than those who did not receive hypothermia treatment. Conclusions This study found that older age (≥ 65 years) and therapeutic hypothermia were independently associated with the risk of EOVAP in NICU patients.