Functional study of a lytic polysaccharide monooxygenase MsLPMO3 from Morchella sextelata in the oxidative degradation of cellulose.

Lytic polysaccharide monooxygenases (LPMOs) can improve the effectiveness with which agricultural waste is utilized. This study described the potent AA9 family protein MsLPMO3, derived from Morchella sextelata. It exhibited strong binding to phosphoric acid swollen cellulose (PASC), and had the considerable binding ability to Cu2+ with a Kd value of 2.70 µM by isothermal titration calorimetry (ITC). MsLPMO3 could also act on PASC at the C1 carbon via MALDI-TOF-MS results. Moreover, MsLPMO3 could boost the hydrolysis efficiency of corncob and wheat bran in combination with glycoside hydrolases. MsLPMO3 also exhibited strong oxidizing ability for 2,6-dimethoxyphenol (2,6-DMP), achieving the best Vmax value of 443.36 U·g-1 for pH 7.4 with a H2O2 concentration of 300 µM. The structure of MsLPMO3 was obtained using AlphaFold2, and the molecular docking results elucidated the specific interactions and key residues involved in the recognition process between MsLPMO3 and cellulose. Altogether, this study expands the knowledge of AA9 family proteins in cellulose degradation, providing valuable insights into the mechanisms of synergistic degradation of lignocellulose with cellulases.

MG-SIN: Multigraph Sparse Interaction Network for Multitask Stance Detection.

Stance detection on social media aims to identify if an individual is in support of or against a specific target. Most existing stance detection approaches primarily rely on modeling the contextual semantic information in sentences and neglect to explore the pragmatics dependency information of words, thus degrading performance. Although several single-task learning methods have been proposed to capture richer semantic representation information, they still suffer from semantic sparsity problems caused by short texts on social media. This article proposes a novel multigraph sparse interaction network (MG-SIN) by using multitask learning (MTL) to identify the stances and classify the sentiment polarities of tweets simultaneously. Our basic idea is to explore the pragmatics dependency relationship between tasks at the word level by constructing two types of heterogeneous graphs, including task-specific and task-related graphs (tr-graphs), to boost the learning of task-specific representations. A graph-aware module is proposed to adaptively facilitate information sharing between tasks via a novel sparse interaction mechanism among heterogeneous graphs. Through experiments on two real-world datasets, compared with the state-of-the-art baselines, the extensive results exhibit that MG-SIN achieves competitive improvements of up to 2.1% and 2.42% for the stance detection task, and 5.26% and 3.93% for the sentiment analysis task, respectively.

Ceftazidime/avibactam combined with colistin: a novel attempt to treat carbapenem-resistant Gram-negative bacilli infection.

BACKGROUND: The rapid global emergence and spread of carbapenem-resistant Gram-negative bacilli (CR-GNB) is recognized as a major public health concern, and there are currently few effective treatments for CR-GNB infection. The aim of this study was to investigate the clinical characteristics and outcomes of patients with CR-GNB infections treated with ceftazidime/avibactam (CAZ/AVI) combined with colistin from October 2019 to February 2023 in China. METHODS: A total of 31 patients with CR-GNB infections were retrospectively identified using the electronic medical record system of Zhejiang Provincial People's Hospital. RESULTS: Thirty-one patients were treated with CAZ/AVI combined with colistin. Respiratory tract infections (87%) were most common. The common drug-resistant bacteria encompass Klebsiella pneumonia (54.8%), Acinetobacter baumannii (29.0%), and Pseudomonas aeruginosa (16.1%). The 30-day mortality rate was 29.0%, and the 7-day microbial clearance rate was 64.5%. The inflammatory marker CRP changes, but not PCT and WBC, were statistically significant on days 7 and 14 after combination therapy. There were seven patients developing acute renal injury (AKI) after combination therapy and treating with continuous renal replacement therapy (CRRT). Two patients developed diarrhea. CONCLUSION: The combination of CAZ/AVI and colistin has potential efficacy in patients with CR-GNB infection, but more studies are needed to determine whether it can reduce 30-day mortality rates and increase 7-day microbial clearance. At the same time, the adverse reactions of combination therapy should not be ignored.

Current status and prospects of basic research and clinical application of mesenchymal stem cells in acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS) is a common and clinically devastating disease that causes respiratory failure. Morbidity and mortality of patients in intensive care units are stubbornly high, and various complications severely affect the quality of life of survivors. The pathophysiology of ARDS includes increased alveolar-capillary membrane permeability, an influx of protein-rich pulmonary edema fluid, and surfactant dysfunction leading to severe hypoxemia. At present, the main treatment for ARDS is mechanical treatment combined with diuretics to reduce pulmonary edema, which primarily improves symptoms, but the prognosis of patients with ARDS is still very poor. Mesenchymal stem cells (MSCs) are stromal cells that possess the capacity to self-renew and also exhibit multilineage differentiation. MSCs can be isolated from a variety of tissues, such as the umbilical cord, endometrial polyps, menstrual blood, bone marrow, and adipose tissues. Studies have confirmed the critical healing and immunomodulatory properties of MSCs in the treatment of a variety of diseases. Recently, the potential of stem cells in treating ARDS has been explored via basic research and clinical trials. The efficacy of MSCs has been shown in a variety of in vivo models of ARDS, reducing bacterial pneumonia and ischemia-reperfusion injury while promoting the repair of ventilator-induced lung injury. This article reviews the current basic research findings and clinical applications of MSCs in the treatment of ARDS in order to emphasize the clinical prospects of MSCs.

Position control method for ultrasonic motors based on beat traveling wave theory.

Focusing on the application demand of ultrasonic motors in the field of space laser communication, a position control method is proposed in this study. Unlike other existing localization methods, this method is based on beat traveling wave theory, which possesses a particular performance in ultrasonic motors. In order to make the speed predictably drop to zero, the frequency difference of the two-phase drive signals is changed during normal operation. This motor deceleration stage is used to establish the positioning scheme. According to this scheme, the finite element analysis with commercial software ADINA is utilized to study the positioning characteristics and support the feasibility, adding details to the scheme. An experimental setup that depends on a DDS signal generator is built to validate this method. The data proves that it can achieve effective average results of about 15 arc-sec under open-loop control at low speed and fluctuate within 0.5 mrad, which can meet the requirement for engineering. Compared to conventional position control methods, it has attractive features of short positioning time, noiseless operation and simple control. This method provides selectivity for engineering applications of ultrasonic motors.

Design and Dynamic Simulation of a Novel Traveling Wave Linear Ultrasonic Motor.

To overcome the problem of frequency consistency and simplify the design process of linear ultrasonic motor, a novel traveling wave linear ultrasonic motor with a ring-type stator is proposed in this paper. The combination of two orthogonal bending vibration modes with the same order is selected as the operating mode of the motor. A traveling wave along the side of the stator is utilized to drive the slider to move linearly. The stator adopts a ring symmetrical structure, which can effectively ensure that the resonance frequencies of the two vibration modes are consistent. Thus, we do not need to tune the frequencies of the two vibrations by constantly adjusting the shape of the stator or designing complex clamping parts to fix the stator without making any influence on the vibrations. Meanwhile, a three-dimensional finite element model of the motor is built. Using the model, we obtain the elliptical motion trajectories of the stator driving surface, the output performance of the motor, the sticking-slipping-separation contact characteristic between the stator and the slider and fabricate and measure a prototype of the proposed motor.

Risk Culture and COVID-19 Protective Behaviors: A Cross-Sectional Survey of Residents in China.

The COVID-19 outbreak caused by the Severe Acute Respiratory Syndrome CoronaVirus type 2 (SARS-CoV-2) has spread across the world. However, our understanding of the public responses, in particular in adopting protective behaviors, has been limited. The current study aimed to determine the level of protective behaviors adopted by the residents in China and its association with their cultural attributes. A national cross-sectional online survey was conducted in mainland China from 4th to 13th August 2020. Protective behaviors were assessed as a summed score (ranging from 0 to 40) measured by ten items. The self-report tendency of study participants toward the four cultural attributes (individualism, egalitarianism, fatalism, hierarchy) was rated on a seven-point Likert scale. A total of 17651 respondents returned a valid questionnaire, representing 47.9% of those who accessed the online survey. Most (89.8%) respondents aged between 18 and 45 years in the age range of and 47.7% were male. High levels of protective behaviors (34.04 ± 5.78) were reported. The respondents had high scores in the cultural attributes of hierarchy (Median = 5) and egalitarianism (Median = 5), compared with low scores in individualism (Median = 1) and fatalism (Median = 1). High levels of protective behaviors were associated a higher tendency toward egalitarianism (AOR = 2.90, 95% CI 2.67-3.15) and hierarchy (AOR = 1.66, 95% CI 1.53-1.81) and a low tendency toward fatalism (AOR = 1.79, 95% CI 1.63-1.97) and individualism (AOR = 2.62, 95% CI 2.41-2.85). The cultural attributes explained 17.3% of the variations in the protective behavioral scores. In conclusion, the adoption of protective behaviors is associated a risk culture characterized by high levels of hierarchy and egalitarianism and low levels of individualism and fatalism. Government actions and communication strategies need to adapt to the cultural characteristics of their target audience.

Proteomic Analysis Demonstrates a Molecular Dialog Between Trichoderma guizhouense NJAU 4742 and Cucumber (Cucumis sativus L.) Roots: Role in Promoting Plant Growth.

Trichoderma is a genus of filamentous fungi that play notable roles in stimulating plant growth after colonizing the root surface. However, the key proteins and molecular mechanisms governing this stimulation have not been completely elucidated. In this study, Trichoderma guizhouense NJAU 4742 was investigated in a hydroponic culture system after interacting with cucumber roots. The total proteins of the fungus were characterized, and the key metabolic pathways along with related genes were analyzed through proteomic and transcriptomic analyses. The roles played by the regulated proteins during the interaction between plants and NJAU 4742 were further examined. The intracellular or extracellular proteins from NJAU 4742 and extracellular proteins from cucumber were quantified, and the high-abundance proteins were determined which were primarily involved in the shikimate pathway (tryptophan, tyrosine, and phenylalanine metabolism, auxin biosynthesis, and secondary metabolite synthesis). Moreover, 15N-KNO3 labeling analysis indicated that NJAU 4742 had a strong ability to convert nitrogenous amino acids, nitrate, nitrile, and amines into ammonia. The auxin synthesis and ammonification metabolism pathways of NJAU 4742 significantly contributed to plant growth. The results of this study demonstrated the crucial metabolic pathways involved in the interactions between Trichoderma spp. and plants.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Proteomic analysis reflects an environmental alkalinization-coupled pH-dependent mechanism of regulating lignocellulases in Trichoderma guizhouense NJAU4742.

BACKGROUND: Filamentous fungi have the ability to efficiently decompose plant biomass, and thus are widely used in the biofuel and bioprocess industries. In process, ambient pH has been reported to strongly affect the performance of the applied functional filamentous fungi. In this study, Trichoderma guizhouense NJAU4742 was investigated under the fermentation of rice straw at different initial pH values for a detailed study. RESULTS: The results showed that NJAU4742 strain could tolerate ambient pH values ranging from 3.0 to 9.0, but had significantly higher growth speed and extracellular enzyme activities under acidic conditions. At low ambient pH (< 4), NJAU4742 strain achieved rapid degradation of rice straw by elevating the ambient pH to an optimal range through environmental alkalinization. Further proteomic analysis identified a total of 1139 intracellular and extracellular proteins during the solid-state fermentation processes, including the quantified 190 carbohydrate-active enzymes (CAZymes) responsible for rice straw degradation, such as 19 cellulases, 47 hemicellulases and 11 chitinases. Meanwhile, the analysis results clearly showed that the secreted lignocellulases had a synergistic trend in distribution according to the ambient pH, and thus led to a pH-dependent classification of lignocellulases in T. guizhouense NJAU4742. CONCLUSIONS: Most functional lignocellulases were found to be differently regulated by the ambient pH in T. guizhouense NJAU4742, which had the ability of speeding up biomass degradation by elevating the ambient pH through environmental alkalinization. These findings contribute to the theoretical basis for the biodegradation of plant biomass by filamentous fungi in the biofuel and bioprocess industries.

Motion Segmentation & Multiple Object Tracking by Correlation Co-Clustering.

Models for computer vision are commonly defined either w.r.t. low-level concepts such as pixels that are to be grouped, or w.r.t. high-level concepts such as semantic objects that are to be detected and tracked. Combining bottom-up grouping with top-down detection and tracking, although highly desirable, is a challenging problem. We state this joint problem as a co-clustering problem that is principled and tractable by existing algorithms. We demonstrate the effectiveness of this approach by combining bottom-up motion segmentation by grouping of point trajectories with high-level multiple object tracking by clustering of bounding boxes. We show that solving the joint problem is beneficial at the low-level, in terms of the FBMS59 motion segmentation benchmark, and at the high-level, in terms of the Multiple Object Tracking benchmarks MOT15, MOT16 and the MOT17 challenge, and is state-of-the-art in some metrics.