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Sepsis is characterized by a dysregulation of immune response to infection, leading to life-threatening organ dysfunction. Sepsis-associated liver injury (SALI) is considered an independent risk factor for predicting death in the intensive care unit (ICU). With the increasing number of studies on the gut-liver axis in recent years, the close linkage of gut microbiota and liver diseases has been gradually revealed. Dysbiosis of gut microbiota has been shown to induce SALI through the mitogen-activated protein kinase/nuclear transcription factorκB (MAPK/NF-κB) signaling pathway and damage to the intestinal barrier. Meanwhile, fecal microbiota transplantation (FMT) and the application of probiotics have great potential in the treatment of SALI. This paper reviews the relevant research progress in recent years both at home and abroad, in order to provide new insights into the pathogenesis and treatment of SALI.

Objective To investigate the related risk factors affecting postoperative recurrence and recurrent metastasis in the patients with gastrointestinal neuroendocrine tumors (GI-NETs), and compare the therapeutic efficacy of different surgical methods as well as their impacts on prognosis. Methods The clinical data of 153 GI-NETs patients treated in our hospital from January 2010 to December 2019 were collected and retrospectively analyzed. The clinical characteristics and 5-year recurrence and metastasis rates were analyzed and calculated, and the prognostic factors and survival analysis was subsequently performed. In addition, the therapeutic efficacy was evaluated and compared between the endoscopic surgery and conventional surgery. Results Among the 153 GI-NETs patients, 90 were males (58.82%) and 63 females (41.18%). According to the 2010 WHO NETs classification, 114 cases (74.51%) were in G1 phases, 25 (16.34%) in G2 phases and 14 (9.15%) in G3 phases. And 112 patients (73.20%) underwent endoscopic surgery and 41 (26.80%) received conventional surgery. There were 26 cases (16.99%) experiencing recurrence and metastasis within 5 years, with the percentages of 1.31%, 3.92%, 3.27% and 8.50%, respectively in the duodenum, esophagus, stomach and rectum. The rates of recurrence and metastasis were 3.92% and 13.07% respectively in the endoscopic surgery and conventional surgery. Log-rank test results indicated that there were statistical differences in the recurrence and metastasis of GI-NETs among different ages, tumor sites, tumor sizes, pathological grades, and surgical methods (P < 0.05). Multivariate Cox regression analysis showed that tumor size, pathological grade, and presence of tumor in the margin were independent risk factors affecting postoperative recurrence and metastasis (P < 0.05), and the larger the tumor size and the higher the pathological grade, the higher the risks were. No statistical differences were seen in the recurrence and metastasis rates in the patients with G1 or G2 phase GI-NETs less than 2 cm, regardless of the surgery methods they received (P>0.05). Conclusion Tumor size, pathological grade and presence of tumor in the margin are independent risk factors for postoperative recurrence and metastasis. GI-NETs in G1 and G2 phases less than 2 cm can be resected under endoscopy.

Alpine treelines are considered ecological monitors recording the impacts of climate change on trees and forests. To date, most treeline research has focused on how climate change drives treeline dynamics. However, little is known about how biotic interactions mediate treeline shifts, particularly in the case of tree recruitment, a bottleneck of treeline dynamics. We hypothesized that inter- and intraspecific facilitation determined the establishment and survival of tree seedlings at alpine treelines. To test this hypothesis, 630 Abies georgei var. smithii seedlings with different ages (4–6, 7–9 and 10–15 years old) were transplanted into three growth habitats (canopy-in, canopy-out and meadow) across the alpine treeline ecotone (4300–4500 m) in the Sygera Mountains, on the southeastern Qinghai-Tibetan Plateau. Microclimate, height growth, mortality rates and leaf functional traits of transplanted seedlings were measured over 3 years. We found that the variations in leaf functional traits were driven by microclimate. After the transplantation, the leaf concentrations of soluble sugars and starch and C:P ratio increased, whereas leaf size decreased. The resource use of seedlings gradually shifted to a more conservative strategy as indicated by changes in non-structural carbohydrates and nutrient concentrations. Radiation, temperature and moisture conditions, mediated by plant interactions, influenced seedling mortality and annual growth by affecting leaf morphological traits. Our findings illustrate how facilitation plays a crucial role in altering solar radiation and leaf trait functioning, determining seedling survival and growth at alpine treelines. We provide new insights into the underlying mechanisms for tree establishment and alpine treeline shifts in response to climate change. [ABSTRACT FROM AUTHOR]

Atmospheric turbulence causes transmitted light to fade randomly, which results in irradiance scintillation fluctuations in the received signal and significantly affects the quality of wireless optical communication systems. In this paper, we investigate the propagation characteristics of a monochromatic light-emitting diode (LED) light beam through weak-to-strong turbulence. Considering the spatial incoherence of a monochromatic LED light source, the emitted light field of a monochromatic LED light source is represented by a random field multiplied by a deterministic field that follows a Gaussian distribution. Then, based on the extended-Rytov theory, a closed expression for the irradiance scintillation index under weak-to-strong turbulence is derived. In addition, the expression for the fading probability governed by the Gamma–Gamma model is given. Finally, the effects of near-earth atmospheric refractive index structural parameters, signal propagation distances, and working light wavelengths on propagation characteristics of the LED-based VLC system are simulated and compared with those of the laser-based one. The results theoretically confirm that laser light sources are more susceptible to atmospheric turbulence along the propagation path than monochromatic LED light sources. The investigation in this paper can provide theoretical support for the design of visible light communication systems in practical applications. [ABSTRACT FROM AUTHOR]