Multiple Second-Order Generalized Integrators Based Comb Filter for Fast Selective Harmonic Extraction

Fast and accurate harmonic extraction plays a vital role in power quality assessment, grid synchronization, harmonic compensation, etc. This paper proposes a multiple second-order generalized integrators (SOGIs) based comb filter (SOGIs-CF) for fast selective harmonic extraction. Compared with the conventional multiple SOGI-quadrature signal generators (SOGI-QSGs) scheme, the tedious harmonic decoupling network (HDN) is removed off without sacrificing steady-state detection accuracy, and thus the computation burden can be reduced. In addition, the parameters design criteria and the digital implementation issues have been discussed in detail. Finally, the experimental results confirm the fast response and high detection accuracy of the proposed scheme. The characteristic of fast harmonic magnitude signal detection makes the proposed method quite suitable for the realization of flexible output capacity-limit control of multifunction inverters

Dietary Supplementation With High Fiber Alleviates Oxidative Stress and Inflammatory Responses Caused by Severe Sepsis in Mice Without Altering Microbiome Diversity

In this study, we demonstrated the effects of a high-fiber diet on intestinal lesions, oxidative stress and systemic inflammation in a murine model of endotoxemia. C57BL/6 mice were randomly assigned to four groups: the control group (CONTROL), which received a commercial normal-fiber rodent diet comprising normal fiber; a CLP group, which received a commercial normal-fiber rodent diet and underwent caecal ligation puncture (CLP); a high-fiber group (HFG), which received a commercial high-fiber rodent diet; and a high fiber + CLP group (HFCLP) which received a commercial high-fiber rodent diet and underwent CLP (30%). The sepsis model was created via CLP after 2 weeks of dietary intervention. Notably, dietary high-fiber supplementation in HFCLP group improved survival rates and reduced bacterial loads, compared with CLP alone. In the HFCLP group, dietary fiber supplementation decreased the serum concentrations of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6) and high-mobility group protein 1 (HMG-1) but raised the concentration of interleukin 10 (IL-10), compared with the levels in CLP mice. Meanwhile, high-fiber supplementation increased the relative proportions of Akkermansia and Lachnospiraceae. These data show that dietary high-fiber supplementation may be therapeutic for sepsis-induced lesions

Deep Reinforcement Learning Framework for Thoracic Diseases Classification via Prior Knowledge Guidance

The chest X-ray is often utilized for diagnosing common thoracic diseases. In recent years, many approaches have been proposed to handle the problem of automatic diagnosis based on chest X-rays. However, the scarcity of labeled data for related diseases still poses a huge challenge to an accurate diagnosis. In this paper, we focus on the thorax disease diagnostic problem and propose a novel deep reinforcement learning framework, which introduces prior knowledge to direct the learning of diagnostic agents and the model parameters can also be continuously updated as the data increases, like a person's learning process. Especially, 1) prior knowledge can be learned from the pre-trained model based on old data or other domains' similar data, which can effectively reduce the dependence on target domain data, and 2) the framework of reinforcement learning can make the diagnostic agent as exploratory as a human being and improve the accuracy of diagnosis through continuous exploration. The method can also effectively solve the model learning problem in the case of few-shot data and improve the generalization ability of the model. Finally, our approach's performance was demonstrated using the well-known NIH ChestX-ray 14 and CheXpert datasets, and we achieved competitive results. The source code can be found here: \url{https://github.com/NeaseZ/MARL}

Neurometabolic and structural alterations of medial septum and hippocampal CA1 in a model of post-operative sleep fragmentation in aged mice: a study combining 1H-MRS and DTI

Post-operative sleep disturbance is a common feature of elderly surgical patients, and sleep fragmentation (SF) is closely related to post-operative cognitive dysfunction (POCD). SF is characterized by sleep interruption, increased number of awakenings and sleep structure destruction, similar to obstructive sleep apnea (OSA). Research shows that sleep interruption can change neurotransmitter metabolism and structural connectivity in sleep and cognitive brain regions, of which the medial septum and hippocampal CA1 are key brain regions connecting sleep and cognitive processes. Proton magnetic resonance spectroscopy (1H-MRS) is a non-invasive method for the evaluation of neurometabolic abnormalities. Diffusion tensor imaging (DTI) realizes the observation of structural integrity and connectivity of brain regions of interest in vivo. However, it is unclear whether post-operative SF induces harmful changes in neurotransmitters and structures of the key brain regions and their contribution to POCD. In this study, we evaluated the effects of post-operative SF on neurotransmitter metabolism and structural integrity of medial septum and hippocampal CA1 in aged C57BL/6J male mice. The animals received a 24-h SF procedure after isoflurane anesthesia and right carotid artery exposure surgery. 1H-MRS results showed after post-operative SF, the glutamate (Glu)/creatine (Cr) and glutamate + glutamine (Glx)/Cr ratios increased in the medial septum and hippocampal CA1, while the NAA/Cr ratio decreased in the hippocampal CA1. DTI results showed post-operative SF decreased the fractional anisotropy (FA) of white matter fibers in the hippocampal CA1, while the medial septum was not affected. Moreover, post-operative SF aggravated subsequent Y-maze and novel object recognition performances accompanied by abnormal enhancement of glutamatergic metabolism signal. This study suggests that 24-h SF induces hyperglutamate metabolism level and microstructural connectivity damage in sleep and cognitive brain regions in aged mice, which may be involved in the pathophysiological process of POCD

Hydrogen gas presents a promising therapeutic strategy for sepsis. Biomed Res Int

Sepsis is characterized by a severe inflammatory response to infection. It remains a major cause of morbidity and mortality in critically ill patients despite developments in monitoring devices, diagnostic tools, and new therapeutic options. Recently, some studies have found that molecular hydrogen is a new therapeutic gas. Our studies have found that hydrogen gas can improve the survival and organ damage in mice and rats with cecal ligation and puncture, zymosan, and lipopolysaccharide-induced sepsis. The mechanisms are associated with the regulation of oxidative stress, inflammatory response, and apoptosis, which might be through NF-B and Nrf2/HO-1 signaling pathway. In this paper, we summarized the progress of hydrogen treatment in sepsis

Protective Effects of Hydrogen on Myocardial Mitochondrial Functions in Septic Mice

Enhancement of mitochondrial physiological function prevents sepsis-induced dysfunction. The present study aimed to elucidate the mechanism by which hydrogen (H2) affects mitochondrial function in a wild-type (WT) and homozygous nuclear factor erythroid 2-related factor 2 (Nrf2) knockout (KO, Nrf2−/−) murine model of sepsis. In myocardial tissues with severe sepsis, H2 gas treatment reduced mitochondrial dysfunction, whereas zinc protoporphyrin (ZnPPIX) negated these beneficial effects. H2 treatment upregulated the protein expression of mitofusin-2 (Mfn2), peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α), and protein heme oxygenase-1 (HO-1) in WT mice with severe sepsis but not in their Nrf2−/− counterparts, and this upregulation was inhibited in the presence of ZnPPIX. In conclusion, the mechanism by which H2 limits organ damage in mice with severe sepsis involves HO-1, whereas the mechanism that limits severe sepsis-related mitochondrial dysfunction involves both HO-1 and Nrf2

N6-methyladenosine (m6A) methyltransferase METTL3 regulates sepsis-induced myocardial injury through IGF2BP1/HDAC4 dependent manner

METTL3 promotes LPS-induced cardiomyocytes inflammatory damage via IGF2BP1/m6A/HDAC4 axis

Association between furosemide administration and clinical outcomes in patients with sepsis-associated acute kidney injury receiving renal replacement therapy: a retrospective observational cohort study based on MIMIC-IV database

Objective To investigate the association between furosemide administration and clinical outcomes in patients with sepsis-associated acute kidney injury (SAKI) receiving renal replacement therapy (RRT).Design A retrospective observational cohort study.Setting The data were collected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database, which contains clinical data from more than 380 000 patients admitted to the intensive care units (ICUs) of the Beth Israel Deaconess Medical Center from 2008 to 2019.Participants All adult patients with SAKI receiving RRT were enrolled. Data for each patient within the first 24 hours of ICU admission were extracted from the MIMIC-IV database.Primary and secondary outcome measures The primary outcome was in-hospital mortality, and the secondary outcome was the length of hospital stay, length of ICU stay, RRT-free time and ventilator-free time. Logistic regression was used to investigate the association between furosemide administration and in-hospital mortality. Subgroup analysis was employed to explore the potential sources of heterogeneity.Results A total of 1663 patients with SAKI receiving RRT were enrolled in the study, of whom 991 patients (59.6%) were retrospectively allocated to the Furosemide group and 672 (40.4%) patients to the non-furosemide group. Univariate and multivariate logistic regression showed that furosemide administration was associated with reduced in-hospital mortality, respectively ((OR 0.77; 95% CI 0.63 to 0.93; p=0.008 < 0.05), (OR 0.59; 95% CI 0.46 to 0.75; p<0.001)). The association remained robust to different ways of adjusting for baseline confounding (all p<0.05). Subgroup analysis suggested that AKI-stage may be a source of heterogeneity. Patients in the furosemide group also had longer RRT-free time (p<0.001) and longer ventilator-free time (p<0.001) than those in the non-furosemide group.Conclusions Furosemide is associated with decreased in-hospital mortality, longer RRT-free time and ventilator-free time in patients with SAKI receiving RRT