ODE-based Recurrent Model-free Reinforcement Learning for POMDPs

Neural ordinary differential equations (ODEs) are widely recognized as the standard for modeling physical mechanisms, which help to perform approximate inference in unknown physical or biological environments. In partially observable (PO) environments, how to infer unseen information from raw observations puzzled the agents. By using a recurrent policy with a compact context, context-based reinforcement learning provides a flexible way to extract unobservable information from historical transitions. To help the agent extract more dynamics-related information, we present a novel ODE-based recurrent model combines with model-free reinforcement learning (RL) framework to solve partially observable Markov decision processes (POMDPs). We experimentally demonstrate the efficacy of our methods across various PO continuous control and meta-RL tasks. Furthermore, our experiments illustrate that our method is robust against irregular observations, owing to the ability of ODEs to model irregularly-sampled time series.Comment: Accepted by NeurIPS 202

Antimicrobial resistance and genomic characteristics of Salmonella from broilers in Shandong Province

IntroductionThe emergence of multidrug-resistant (MDR) strains of Salmonella, which is a genus of important zoonotic pathogens, has aroused great public health concern worldwide.MethodsIn this study, 167 strains of Salmonella were isolated from 947 samples from broiler farms, slaughterhouses, and markets in Shandong Province. Antibiotic sensitivity testing was performed, and 70 strains of Salmonella were screened out by whole-genome sequencing (WGS) to evaluate serotypes, antimicrobial resistance genes (ARGs), the prevalence of class 1 integrons, the plasmid carriage rate, and phylogenetic characteristics and for multilocus sequence typing (MLST).ResultsThe results showed that the 167 isolates showed the highest resistance to ampicillin (AMP, 87.4%), sulfamethoxazole (SF, 87.4%), compound sulfamethoxazole (SXT, 81.4%), nalidixic acid (NAL, 80.2%), and amoxicillin/clavulanic acid (A/C, 77.8%). All the strains were sensitive to meropenem (MEM), and 91.0% of the isolates were MDR strains. We screened a total of 45 ARGs, with the highest detection rate observed for the tetracycline (TET) resistance gene tet (A) (81.4%). A total of 21 types of plasmid replicons were detected in Salmonella, of which IncX1 was the most common (74.3%), and 62.9% of the isolates carried a class 1 integron. In addition, a total of 11 different serotypes were detected, with S. enteritidis as the predominant serovar., followed by S. infantis and S. Newport. Twelve different sequence types (STs) were detected, among which ST11 was the main type. There was a strong correspondence between serotypes and STs. We also found that S. Indiana and S. Kentucky had extremely high rates of resistance to ciprofloxacin (CIP) and third-generation cephalosporins. System-wide genome analysis showed the occurrence of long-distance transmission across fields.ConclusionIn conclusion, the detection of multidrug resistance and isolates carrying multidrug resistance genes is the main problem, and emergency strategies should be implemented to address this issue

Sevoflurane Pre-conditioning Ameliorates Diabetic Myocardial Ischemia/Reperfusion Injury Via Differential Regulation of p38 and ERK.

Diabetes mellitus (DM) significantly increases myocardial ischemia/reperfusion (MI/R) injury. During DM, cardioprotection induced by conventional pre-conditioning (PreCon) is decreased due to impaired AMP-activated protein kinase (AMPK) signaling. The current study investigated whether PreCon with inhaled anesthetic sevoflurane (SF-PreCon) remains cardioprotective during DM, and identified the involved mechanisms. Normal diet (ND) and high-fat diet (HFD)-induced DM mice were randomized into control and SF-PreCon (3 cycles of 15-minute period exposures to 2% sevoflurane) groups before MI/R. SF-PreCon markedly reduced MI/R injury in DM mice, as evidenced by improved cardiac function (increased LVEF and ±Dp/dt), decreased infarct size, and decreased apoptosis. To determine the relevant role of AMPK, the effect of SF-PreCon was determined in cardiac-specific AMPKα2 dominant negative expressing mice (AMPK-DN). SF-PreCon decreased MI/R injury in AMPK-DN mice. To explore the molecular mechanisms responsible for SF-PreCon mediated cardioprotection in DM mice, cell survival molecules were screened. Interestingly, in ND mice, SF-PreCon significantly reduced MI/R-induced activation of p38, a pro-death MAPK, without altering ERK and JNK. In DM and AMPK-DN mice, the inhibitory effect of SF-PreCon upon p38 activation was significantly blunted. However, SF-PreCon significantly increased phosphorylation of ERK1/2, a pro-survival MAPK in DM and AMPK-DN mice. We demonstrate that SF-PreCon protects the heart via AMPK-dependent inhibition of pro-death MAPK in ND mice. However, SF-PreCon exerts cardioprotective action via AMPK-independent activation of a pro-survival MAPK member in DM mice. SF-PreCon may be beneficial compared to conventional PreCon in diabetes or clinical scenarios in which AMPK signaling is impaired

Efficient 2075-nm Laser Emission From Ho3+-Doped Fluorotellurite Glass in a Compact All-Fiber Structure

In this Letter, we report an Ho3+-doped fluorotellurite glass all-fiber laser at 2075 nm. The gain fiber is pumped in-band with a 1976-nm fiber laser and connected by fusion splicing. A high-quality fusion splicing point with a loss of \u3c 0.1 dB was obtained by finely adjusting the splicing power and offset. In addition, by optimizing the writing parameters, a third-order fiber Bragg grating (FBG) with a reflectivity of 98% was achieved at 2075 nm using the femtosecond laser direct-writing method. Using the FBG as the laser cavity mirror and a relatively short 28-cm-long home-made Ho3+-doped fluorotellurite fiber as the laser medium, a laser with a maximum unsaturated output power of 7.33 W was obtained, and the corresponding slope efficiency was as high as 93.4%. The first, to the best of our knowledge, demonstration of the fluorotellurite glass all-fiber ∼2.1-µm laser presented in this work may pave the way for a high-power 2.1-µm fiber laser with a compact structure

Correlation between tongue manifestations and glucose, total cholesterol, and high-density lipoprotein cholesterol in patients with acute cerebral infarction

AbstractObjectiveTo analyze the association between tongue manifestations and the levels of glucose (GLU), total cholesterol (TCH), and high-density lipoprotein cholesterol (HDL-C) in subjects with acute cerebral infarction.MethodsHospitalized patients with first unilateral cerebral infarction in the Neurological Department of Xuanwu Hospital were included and the correlation between tongue fur color, fur nature, and the levels of GLU, TCH, HDL-C were analyzed.ResultsHDL level in the thin fur group was higher than that in the thick fur group (P=0.02). The difference in the levels of GLU, TCH, and HDL-C among the groups was significant (P<0.05), classified in terms of slippery, moist, and dry fur. Further comparison between the groups by Student-Newman-Keuls test showed that GLU level in the dry fur group was the highest. Moreover, the TCH level in the slippery fur group was higher than the other two groups.ConclusionA correlation between tongue manifestations and GLU, TCH, HDL-C was identified in the patients with acute cerebral infarction

A bathypelagic ostracod Conchoecissa nigromaculatus sp. nov. (Myodocopa, Halocyprididae) from the South China Sea

Pelagic ostracods are one of the main groups of zooplankton and are abundant in marine ecosystems worldwide. The record of marine planktonic ostracod species in the central and southern part of the South China Sea accounts over for one-third of the total recorded marine planktonic ostracods in seas around China. In this study, we examined and compared the specimens from a recent cruise in this region that appeared to be different from previously described species of genus Conchoecissa, and then confirmed them as a new bathypelagic species Conchoecissa nigromaculatus. These specimens clearly differed from the other species of genus Conchoecissa with differences observed in the size, carapace, locations of glands, mandible, maxilla, sixth limb, and furca. In this species, mandibular coxal endite has no ventral finger process, maxilla has prominently large endites and has only two claws on the tip, the sixth limb has very simple endites, and this species has distinctive features not previously observed in the tribe Conchoeciini before. It is therefore necessary to emend the diagnosis of this group

A clinically relevant online patient QA solution with daily CT scans and EPID-based in vivo dosimetry: A feasible study on rectal cancer

Adaptive radiation therapy (ART) could protect organs at risk (OARs) while maintain high dose coverage to targets. However, there still lack efficient online patient QA methods. We aim to develop a clinically relevant online patient quality assurance (QA) solution for ART using daily CT scans and electronic portal imaging device (EPID)-based in vivo dosimetry. Ten patients with rectal cancer at our center were included. Patients' daily CT scans and portal images were collected to generate reconstructed 3D dose distributions. Contours of targets and OARs were recontoured on these daily CT scans by a clinician or an auto-segmentation algorithm, then dose-volume indices were calculated, and the percent deviation of these indices to their original plans were determined. This deviation was regarded as the metric for clinically relevant patient QA. The tolerance level was obtained using a 95% interval of the QA metric distribution. These deviations could be further divided into anatomically relevant or delivery relevant indicators for error source analysis. Finally, our QA solution was validated on an additional six clinical patients. In rectal cancer, the lower and upper tolerance of the QA metric for PTV {\Delta}D95 (%) were [-3.11%, 2.35%], and for PTV {\Delta}D2 (%) were [-0.78%, 3.23%]. In validation, the 68% for PTV {\Delta}D95 (%) and the 79% for PTV {\Delta}D2 ({%)of the 28 fractions are within tolerances of the QA metrics. By using four or more out-of-tolerance QA metrics as an action level, there were 5 fractions (18%) have four or more out-of-tolerance QA metrics in validation patient dataset. The online patient QA solution using daily CT scans and EPID-based in vivo dosimetry is clinically feasible. Source of error analysis has the potential for distinguishing sources of error and guiding ART for future treatments