AIM To investigate whether gut microbiota metabolite sodium butyrate(Na B)is an effective substance for attenuating non-alcoholic fatty liver disease(NAFLD)and the internal mechanisms.METHODS Male ...C57BL/6J mice were divided into three groups,normal control were fed standard chow and model group were fed a high-fat diet(HFD)for 16 wk,the intervention group were fed HFD for 16 wk and treated with Na B for 8 wk.Gut microbiota from each group were detected at baseline and at 16 wk,liver histology were evaluated and gastrointestinal barrier indicator such as zonula occluden-1(ZO-1)were detected by immunohistochemistry and realtime-PCR,further serum or liver endotoxin were determined by ELISA and inflammation-or metabolism-associated genes were quantified by real-time PCR.RESULTS Na B corrected the HFD-induced gut microbiota imbalance in mice,while it considerably elevated the abundances of the beneficial bacteria Christensenellaceae,Blautia and Lactobacil us.These bacteria can produce butyric acid in what seems like a virtuous circle.And butyrate restored HFD induced intestinal mucosa damage,increased the expression of ZO-1 in small intestine,further decreased the levels of gut endotoxin in serum and liver compared with HF group.Endotoxin-associated genes such as TLR4 and Myd88,pro-inflammation genes such as MCP-1,TNF-α,IL-1,IL-2,IL-6 and IFN-γin liver or epididymal fat were obviously downregulated after Na B intervention.Liver inflammation and fat accumulation were ameliorated,the levels of TG and cholesterol in liver were decreased after Na B intervention,NAS score was significantly decreased,metabolic indices such as FBG and HOMA-IR and liver function indicators ALT and AST were improved compared with HF group.CONCLUSION Na B may restore the dysbiosis of gut microbiota to attenuate steatohepatitis,which is suggested to be a potential gut microbiota modulator and therapeutic substance for NAFLD.
Colloidal quantum dots (QDs) consisting of precious‐metal‐free elements show attractive potentials towards solar‐driven CO2 reduction. However, the inhibition of hydrogen (H2) production in aqueous ...solution remains a challenge. Here, we describe the first example of a carbon–carbon (C−C) coupling reaction to block the competing H2 evolution in photocatalytic CO2 reduction in water. In a specific system taking ZnSe QDs as photocatalysts, the introduction of furfural can significantly suppress H2 evolution leading to CO evolution with a rate of ≈5.3 mmol g−1 h−1 and a turnover number (TON) of >7500 under 24 h visible light. Meanwhile, furfural is upgraded to the self‐coupling product with a yield of 99.8 % based on the consumption of furfural. Mechanistic insights show that the reductive furfural coupling reaction occurs on surface Zn‐sites to consume electrons and protons originally used for H2 production, while the CO formation pathway at surface anion vacancies from CO2 remains.
Reductive carbon–carbon coupling was used to block H2 evolution in CO2 photoreduction in water. Furfural, one of the biomass platform molecules, adsorbs on Zn‐sites consuming electrons and protons originally used for H2 production, but the CO formation pathway at surface anion vacancies remains. Therefore, CO was evolved with a CO/H2 ratio of 265 : 1 in the gas phase and furfural was upgraded to value‐added hydrofuroin.
Background
Obesity may impact surgical outcomes of gastrectomy. Whether visceral fat area (VFA) is a better obesity parameter than body mass index (BMI) is still controversial. The aim of this study ...is to compare the accuracy and effectiveness of VFA and BMI in predicting the short-term surgical outcomes of gastrectomy.
Methods
Patients who were diagnosed with gastric cancer were measured for BMI and VFA preoperatively and then divided into a VFA-H (VFA-high) group and VFA-L (VFA-low) group, at the cutoff point of 100 cm
2
, and a BMI-H (BMI-high) group and BMI-L (BMI-low) group, at the cutoff point of 25 kg/m
2
. The short-term surgical outcomes were compared between the different groups.
Results
In total, 276 patients were enrolled in this study; 55 (19.9%) patients were classified into the BMI-H group, and 122 (44.2%) patients were classified into the VFA-H group. There was a significant correlation between BMI and VFA (
r
= 0.652,
p
< 0.001). Compared with the VFA-L group, the VFA-H group had a higher incidence of postoperative complications (31.1% vs. 13.0%;
p
< 0.001), longer operation duration (270.0 (235.0–305.0) vs. 255.0 (223.8–295.0),
p
= 0.046), and more blood loss (100.0 (100.0–150.0) vs. 80.0 (80.0–100.0),
p
< 0.001), while the BMI-H group had more blood loss than the BMI-L group (100.0 (100.0–120.0) vs. 100.0(80.0–100.0),
p
= 0.006). Logistic regression showed that VFA was an independent risk factor for postoperative complications (odds ratio 2.813, 95% CI 1.523–5.194;
p
= 0.001).
Conclusion
For gastric cancer patients, VFA is superior to BMI in accurately and effectively illuminating the impact of obesity on short-term surgical outcomes.
Trial Registration
Clinicaltrials.gov
: NCT02800005.
Inspired by green plants, artificial photosynthesis has become one of the most attractive approaches toward carbon dioxide (CO2) valorization. Semiconductor quantum dots (QDs) or dot‐in‐rod (DIR) ...nano‐heterostructures have gained substantial research interest in multielectron photoredox reactions. However, fast electron–hole recombination or sluggish hole transfer and utilization remains unsatisfactory for their potential applications. Here, the first application of a well‐designed ZnSe/CdS dot‐on‐rods (DORs) nano‐heterostructure for efficient and selective CO2 photoreduction with H2O as an electron donor is presented. In‐depth spectroscopic studies reveal that surface‐anchored ZnSe QDs not only assist ultrafast (≈2 ps) electron and hole separation, but also promote interfacial hole transfer participating in oxidative half‐reactions. Surface photovoltage (SPV) spectroscopy provides a direct image of spatially separated electrons in CdS and holes in ZnSe. Therefore, ZnSe/CdS DORs photocatalyze CO2 to CO with a rate of ≈11.3 µmol g−1 h−1 and ≥85% selectivity, much higher than that of ZnSe/CdS DIRs or pristine CdS nanorods under identical conditions. Obviously, favored energy‐level alignment and unique morphology balance the utilization of electrons and holes in this nano‐heterostructure, thus enhancing the performance of artificial photosynthetic solar‐to‐chemical conversion.
A dot‐on‐rod (DOR) nano‐heterostructure is rationally constructed by anchoring multiple ZnSe QDs on a single CdS nanorod. Due to the favored energy level alignment and the good exposure of ZnSe to the surrounding medium, ultrafast (≈2 ps) charge separation and facile hole utilization are realized, which enable effective and selective CO2‐to‐CO photoreduction taking H2O as an electron donor.
A 16-channel closed-loop neuromodulation system-on-chip (SoC) for human epileptic seizure control is proposed and designed. In the proposed SoC, a 16-channel neural-signal acquisition unit (NSAU), a ...biosignal processor (BSP), a 16-channel high-voltage-tolerant stimulator (HVTS), and wireless power and bidirectional data telemetry are designed. In the NSAU, the input protection circuit is used to prevent MOSFET from overstressing by the high-voltage stimulations. Hence, NSAUs can share electrodes with stimulators. The auto-reset chopper-stabilized capacitive-coupled instrumentation amplifiers (AR-CSCCIAs) are designed with the chopper-stabilized technique with a new offset reduction loop. The measured input-referred noise is 2.09 <inline-formula> <tex-math notation="LaTeX">\mu \textrm {V}_{\mathrm {rms}} </tex-math></inline-formula> and the noise-efficiency factor (NEF) is 3.78. The entropy-and-spectrum seizure detection algorithm is implemented in the BSP with 0.76-s seizure detection latency and 97.8% detection accuracy. When the seizure onset is detected by the BSP, the HVTS with adaptive supply control delivers 0.5-3-mA biphasic current stimulation to suppress the seizure onset. The proposed SoC is powered wirelessly, and the bidirectional data telemetry is realized through the same pair of coils in 13.56 MHz. The downlink data rate is 211 Kb/s with the binary phase-shift keying (BPSK) modulation and a new BPSK demodulator. The uplink data rate is 106 Kb/s with the load-shift keying (LSK) modulation. The proposed SoC is fabricated in a 0.18-<inline-formula> <tex-math notation="LaTeX">\mu \text{m} </tex-math></inline-formula> CMOS technology and occupies 25 mm 2 . Electrical tests have been performed to characterize the SoC performance. In vivo animal experiments using mini-pigs have been performed to successfully verify the closed-loop neuromodulation functions on epileptic seizure suppression.
Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection can cause coronavirus disease 2019 (COVID‐19), an acute respiratory inflammation that has emerged worldwide since December 2019, ...and it quickly became a global epidemic. Inflammatory bowel disease (IBD) is a group of chronic nonspecific intestinal inflammatory diseases whose etiology has not been elucidated. The two have many overlapping symptoms in clinical presentation, such as abdominal pain, diarrhea, pneumonia, etc. Imbalance of the autoimmune system in IBD patients and long‐term use of immunosuppressive drugs may increase the risk of infection; and systemic symptoms caused by COVID‐19 may also induce or exacerbate intestinal inflammation. It has been found that the SARS‐CoV‐2 receptor angiotensin converting enzyme 2, which is highly expressed in the lung and intestine, is an inflammatory protective factor, and is downregulated and upregulated in COVID‐19 and IBD, respectively, suggesting that there may be a coregulatory pathway. In addition, the immune activation pattern of COVID‐19 and the cytokine storm in the inflammatory response have similar roles in IBD, indicating that the two diseases may influence each other. Therefore, this review aimed to address the following research questions: whether SARS‐CoV‐2 infection leads to the progression of IBD; whether IBD increases the risk of COVID‐19 infection and poor prognosis; possible common mechanisms and genetic cross‐linking between the two diseases; new treatment and care strategies for IBD patients, and the feasibility and risk of vaccination in the context of the COVID‐19 epidemic.
Rising CO
concentration, a driving force of climate change, is impacting global food security by affecting plant physiology. Nevertheless, the effects of elevated CO
on primary and secondary ...metabolism in tea plants (Camellia sinensis L.) still remain largely unknown. Here we showed that exposure of tea plants to elevated CO
(800 µmol mol
for 24 d) remarkably improved both photosynthesis and respiration in tea leaves. Furthermore, elevated CO
increased the concentrations of soluble sugar, starch and total carbon, but decreased the total nitrogen concentration, resulting in an increased carbon to nitrogen ratio in tea leaves. Among the tea quality parameters, tea polyphenol, free amino acid and theanine concentrations increased, while the caffeine concentration decreased after CO
enrichment. The concentrations of individual catechins were altered differentially resulting in an increased total catechins concentration under elevated CO
condition. Real-time qPCR analysis revealed that the expression levels of catechins and theanine biosynthetic genes were up-regulated, while that of caffeine synthetic genes were down-regulated in tea leaves when grown under elevated CO
condition. These results unveiled profound effects of CO
enrichment on photosynthesis and respiration in tea plants, which eventually modulated the biosynthesis of key secondary metabolites towards production of a quality green tea.
Recent progress in addressing electrically driven single‐molecule behaviors has opened up a path toward the controllable fabrication of molecular devices. Herein, the selective fabrication of ...single‐molecule junctions is achieved by employing the external electric field. For molecular junctions with methylthio (–SMe), thioacetate (–SAc), amine (–NH2), and pyridyl (–PY), the evolution of their formation probabilities along with the electric field is extracted from the plateau analysis of individual single‐molecule break junction traces. With the increase of the electric field, the SMe‐anchored molecules show a different trend in the formation probability compared to the other molecular junctions, which is consistent with the density functional theory calculations. Furthermore, switching from an SMe‐anchored junction to an SAc‐anchored junction is realized by altering the electric field in a mixed solution. The results in this work provide a new approach to the controllable fabrication and modulation of single‐molecule junctions and other bottom‐up nanodevices at molecular scales.
The selective fabrication of single‐molecule junctions is achieved by interface engineering under the external electric field. This work offers an unprecedented opportunity to investigate single‐molecule behaviors, manipulate single‐molecule in solution, and integrate functional molecules into the specific sites of molecular devices.
Few-shot semantic segmentation aims to segment novel-class objects in a query image with only a few annotated examples in support images. Although progress has been made recently by combining ...prototype-based metric learning, existing methods still face two main challenges. First, various intra-class objects between the support and query images or semantically similar inter-class objects can seriously harm the segmentation performance due to their poor feature representations. Second, the latent novel classes are treated as the background in most methods, leading to a learning bias, whereby these novel classes are difficult to correctly segment as foreground. To solve these problems, we propose a dual-branch learning method. The class-specific branch encourages representations of objects to be more distinguishable by increasing the inter-class distance while decreasing the intra-class distance. In parallel, the class-agnostic branch focuses on minimizing the foreground class feature distribution and maximizing the features between the foreground and background, thus increasing the generalizability to novel classes in the test stage. Furthermore, to obtain more representative features, pixel-level and prototype-level semantic learning are both involved in the two branches. The method is evaluated on PASCAL-5 i 1-shot, PASCAL-5 i 5-shot, COCO-20 i 1-shot, and COCO-20 i 5-shot, and extensive experiments show that our approach is effective for few-shot semantic segmentation despite its simplicity.
Recently, memory-based methods have exhibited remarkable performance in Video Object Segmentation (VOS) by employing non-local pixel-wise matching between the query and memory. Nevertheless, these ...methods suffer from two limitations: 1) Non-local pixel-wise matching can result in the incorrect segmentation of background distractor objects, and 2) memory features with substantial temporal redundancy consume significant computing resources and reduce the inference speed. To address the limitations, we first propose a local attention mechanism to suppress background features, and we introduce a novel training framework based on contrast learning to ensure the network learns reliable and robust pixel-wise correspondence between query and memory. We adaptively determine whether to update the memory based on the variation of foreground objects. Next, we propose a dynamic memory bank, which utilizes a lightweight and differentiable soft modulation gate to determine the number of memory features to remove along the temporal dimension. This allows efficient and flexible management of memory features. Our network achieves competitive results (e.g., 92.1% on DAVIS 2016 val, 87.6%/81.3% on DAVIS 2017 val/test, 87.0% on YouTube-VOS 2018 val) compared with the state-of-the-art methods while maintaining a faster inference speed of 25+FPS. Moreover, our network demonstrates a favorable balance between performance and speed when dealing with the long-time video dataset.
PDF
