Adaptive Neural Control for Hysteretic Nonlinear Systems With Hysteresis Neural Direct Inverse Compensator and Its Application.

Aiming at high precision control for a class of hysteretic nonlinear systems, a new hysteresis direct inverse compensator-based adaptive output feedback control scheme is designed in this article. First, a novel long short-term memory neural network (LSTMNN)-based hysteresis inverse compensator is established to compensate the asymmetric hysteresis nonlinearity, where the LSTMNN is used as the prediction mechanism for model operator weights, rather than the overall mapping of hysteresis input and output. Second, by designing the modified high-gain K -Filter states observer and the error transformed function, the unmeasurable states are estimated with arbitrarily small estimation error and the prespecified tracking performance is achieved. Lastly, the biconical dielectric elastomer actuator (DEA) motion platform is constructed. Then, the effectiveness of the proposed LSTMNN-based hysteresis inverse compensator and control scheme are verified on the experimental platform. The experimental results illustrate the effectiveness and advantages of proposed control scheme.

Serum GSDMD for Early Diagnosis of Bloodstream Infection and Differentiating Bacterial from Fungal Infections.

BACKGROUND: The role of Gasdermin D (GSDMD) in bloodstream infection (BSI) diagnosis is unknown. METHODS: Serum GSDMD levels were measured in BSI patients. Endothelial cells and PBMCs were isolated, infected with bacteria/fungi, and intracellular/extracellular GSDMD concentrations were measured. An animal model was established to investigate the association between serum GSDMD levels and BSI incidence/progression. RESULTS: ROC curve analysis indicated that GSDMD could be a potential early diagnostic biomarker for BSI (AUC = 0.9885). Combining GSDMD with procalcitonin (PCT) improved the differential diagnosis of Gram-positive and Gram-negative bacteria (AUC = 0.6699, 66.15% specificity), and early diagnosis of Gram-positive bacteria (98.46% sensitivity), while PCT was not significantly elevated. The combined GSDMD and G-test had higher sensitivity (AUC = 0.7174) for differential diagnosis of bacterial and fungal infections, and early detection of fungal infections (98.44% sensitivity). In vitro and in vivo experiments confirmed that GSDMD levels increased significantly within 2 hours, peaked at 16 hours, and exhibited a time-dependent upward trend. CONCLUSIONS: Serum GSDMD, alone or combined with other biomarkers, has potential for early diagnosis and differential diagnosis of BSI caused by various pathogens. This finding offers a new strategy for early detection and treatment of BSI.

Decentralized Implicit Inverse Control for Large-Scale Hysteretic Nonlinear Time-Delay Systems and Its Application on Triple-Axis Giant Magnetostrictive Actuators.

This article proposes fuzzy-logic systems (FLSs)-based decentralized adaptive implicit inverse control scheme for a class of large-scale nonlinear systems with time delays and multihysteretic loops. Our novel algorithms feature hysteretic implicit inverse compensators designed to effectively mitigate multihysteretic loops in large-scale systems. In this article, hysteretic implicit inverse compensators can replace the traditional hysteretic inverse models, which are exceedingly difficult to construct, and no longer necessary. The authors provide three contributions: 1) a searching mechanism to obtain the approximate value of the practical input signal from the so-called hysteretic temporary control law; 2) the arbitrarily small L∞ norm of the tracking error attained by utilizing the proposed initializing technique, which applies the combination of FLSs and a finite covering lemma to deal with time delays; and 3) the construction of a triple-axis giant magnetostrictive motion control platform, which validates the effectiveness of the proposed control scheme and algorithms.

Effects of Ion Irradiation and Temperature on Mechanical Properties of GaN Single Crystals under Nanoindentation.

Understanding the impact of irradiation and temperature on the mechanical properties of GaN single crystals holds significant relevance for rational designs and applications of GaN-based transistors, lasers, and sensors. This study systematically investigates the influence of C-ion irradiation and temperature on pop-in events, hardness, Young's modulus, and fracture behavior of GaN single crystals through nanoindentation experiments. In comparison with unirradiated GaN samples, the pop-in phenomenon for ion-irradiated GaN samples is associated with a larger critical indentation load, which decreases with increasing temperature. Both unirradiated and ion-irradiated GaN samples exhibit a decline in hardness with increasing indentation depth, while Young's moduli do not exhibit a clear size effect. In addition, intrinsic hardness displays an inverse relationship with temperature, and ion-irradiated GaN single crystals exhibit greater intrinsic hardness than their unirradiated counterparts. Our analysis further underscores the significance of Peierls stress during indentation, with this stress decreasing as temperature rises. Examinations of optical micrographs of indentation-induced fractures demonstrate an irradiation embrittlement effect. This work provides valuable insights into the mechanical behavior of GaN single crystals under varying irradiation and temperature conditions.

Synthesis of Substituted of Benzo[4,5]imidazo[1,2-a]pyrimidines through (3 + 2+1) Cyclization of 2-Aminobenzimidazole, Acetophenone, and N,N-Dimethylformamide as One-Carbon Synthon.

An efficient method for the construction of benzo[4,5]imidazo[1,2-a]pyrimidines using N,N-dimethylformamide as a one-carbon source and 2-aminobenzimidazoles and acetophenone as substrates through a one-pot, three-component cascade reaction is described. Spectra investigations indicated the fluorescent properties of selected products, exhibiting quantum yields 0.07-0.16 with maxima absorption at 266-294 nm and emission at 472-546 nm.

Transcriptional Profiling and Transposon Mutagenesis Study of the Endophyte Pantoea eucalypti FBS135 Adapting to Nitrogen Starvation.

The research on plant endophytes has been drawing a lot of attention in recent years. Pantoea belongs to a group of endophytes with plant growth-promoting activity and has been widely used in agricultural fields. In our earlier studies, Pantoea eucalypti FBS135 was isolated from healthy-growing Pinus massoniana and was able to promote pine growth. P. eucalypti FBS135 can grow under extremely low nitrogen conditions. To understand the mechanism of the low-nitrogen tolerance of this bacterium, the transcriptome of FBS135 in the absence of nitrogen was examined in this study. We found that FBS135 actively regulates its gene expression in response to nitrogen deficiency. Nearly half of the number (4475) of genes in FBS135 were differentially expressed under this condition, mostly downregulated, while it significantly upregulated many transportation-associated genes and some nitrogen metabolism-related genes. In the downregulated genes, the ribosome pathway-related ones were significantly enriched. Meanwhile, we constructed a Tn5 transposon library of FBS135, from which four genes involved in low-nitrogen tolerance were screened out, including the gene for the host-specific protein J, RNA polymerase σ factor RpoS, phosphoribosamine-glycine ligase, and serine acetyltransferase. Functional analysis of the genes revealed their potential roles in the adaptation to nitrogen limitation. The results obtained in this work shed light on the mechanism of endophytes represented by P. eucalypti FBS135, at the overall transcriptional level, to an environmentally limited nitrogen supply and provided a basis for further investigation on this topic.

A one-pot synthesis of 2,3-disubstituted-4(3H)-quinazolinone from o-aminobenzoic acid and DMF derivatives using imidazole hydrochloride as a promoter.

As a novel and environmentally friendly Brönsted acid, imidazole hydrochloride was used to promote the synthesis of 2,3-disubstituted-4(3H)-quinazolinone from o-aminobenzoic acid and DMF derivatives. The essence of this reaction is a multicomponent reaction, which constructs multiple chemical bonds between different components through the transamidation of imidazole hydrochloride. This protocol showed a wide range of functional group tolerance, and a series of quinazolinones were synthesized in low to moderate yields without metal catalysts, oxidants or other additives.

Changes and protections of urban habitat quality in Shanghai of China.

Habitat quality has been widely used as an important indicator in the evaluation of regional ecological security and ecosystem services. Previous studies have focused on the influences of urbanization on habitat quality, but the protection measures about how to respond to the dynamic changes of habitat quality patterns are still unclear. This study investigated the habitat quality in the metropolitan region of China (Shanghai) by using InVEST model, and analyzed its dynamic changes from 2000 to 2017 for the sake of providing different protection objects and measures for Shanghai. The results showed that the habitat quality index (HQI) in 2017 was 0.42, and the accumulated area percentages of less than 0.4 in HQI reached 46%, whereas the habitat quality in Chongming district was the highest. The HQI and habitat protected index (HPI) showed an obvious decline tendency from suburban area to downtown area. The HQI in Shanghai gradually declined from 0.56 in 2000 to 0.42 in 2017, and the deterioration area in habitat quality nearly covered 33% between 2000 and 2017. Additionally, the area proportion of the median habitat quality (0.4 < HQI ≤ 0.6) drastically dropped, but the areas of the low (HQI ≤ 0.2) and the high (HQI > 0.8) in habitat simultaneously expanded. Therefore, the valuable habitat in the western and southern coastal wetlands, Dianshan lake and Chongming district in Shanghai should be strictly protected, which covered 30% of the metropolitan area in Shanghai, and about 17% of the region located in the inner coastal zones and northern of Chongming Island was in urgent need of habitat restoration. Our results provide vital references for the maintenance and sustainable management of urban habitats in the metropolitan region.

Environment-Dependent Radiation Tolerance of Graphene Transistors under Proton Irradiation.

Electronic devices based on two-dimensional materials are promising for application in space instrumentation because of their small size and low power consumption, and irradiation tolerance of these devices is required because of the existence of energetic particles in aerospace conditions. We investigate the performance degradation of graphene field effect transistors (GFETs) with 3 MeV protons by using an in situ irradiation facility. Our results indicate that GFET performance degraded severely at the ion fluence of 8 × 1011 cm-2. Surprisingly, although the performance of the proton-irradiated GFETs is difficult to recover in vacuum, it can nearly completely recover within hours when the GFET is moved into an air environment, indicating that the performance change is due to the charge accumulation in SiO2 under proton irradiation rather than the lattice damage of graphene. Our results have great importance for the application of 2D devices in aerospace and other radiative environments.

Application and Development of Biocontrol Agents in China.

While the growing population in the world has a large demand for food, agriculture and forestry are currently facing severe challenges due to phytopathogens and pests along with global warming. For half a century chemical pesticides and fertilizers have made a great contribution to agricultural production. However, the excessive use of chemical agents has caused obvious side effects on the environment and the sustainable development of agriculture in the long term. China has recorded one of the fastest economic growths for more than 20 years but at the cost of a seriously polluted environment. Since a decade ago, China has paid increasing attention to environment protection and taken intensified measures for pollution control and ecological restoration. In this context, the biocontrol agent industry in China has experienced a golden decade of rapid development. In this minireview, we will introduce the application and development of microorganism-based biocontrol agents in China over the past two decades.

Protective Effect of Neonatal Hepatitis B Vaccine Against HBV Breakthrough Infection in Children with Leukemia: A Real-world Study.

Background and Aims: Hepatitis B vaccine is the most effective preventive measure against hepatitis B virus (HBV) infection. However, the risk of HBV breakthrough infection in fully immunized children (neonatal hepatitis B immunization) who receive immunosuppressive therapy and transfusion of blood components is not well characterized. In this real-world study, we aimed to investigate the immune protection conferred by neonatal hepatitis B vaccine in children with acute lymphoblastic leukemia (ALL) who were treated with immunosuppressive therapy and blood component transfusions. Methods: Children with ALL who had received all three doses of neonatal hepatitis B vaccine were included in this study. HBV seromarkers were detected before and after the initiation of immunosuppressive therapy. Results: A total of 1,011 children with ALL who were fully vaccinated against hepatitis B in infancy before the initiation of immunosuppressive therapy were eligible for inclusion. HBV infection was detected in four of 410 children (0.98%) with an HBsAg test after the initiation of immunosuppressive therapy. The median interval from treatment initiation was 19 months. Conclusions: Three doses of neonatal hepatitis B vaccine conferred adequate protection. In endemic regions, there is a low risk of HBV breakthrough infection in fully immunized children with immunosuppressive therapy.

Reduced Circulating Soluble Receptor for Advanced Glycation End-products in Chronic Hepatitis B Are Associated with Hepatic Necroinflammation.

The diagnosis and disease management of chronic hepatitis B (CHB) remain challenging due to the elusive assessment of disease severity. Recently, soluble receptor for advanced glycation end-products (sRAGE) has been implicated in the inflammatory-immune response initiated by liver injury. Nonetheless, its natural behavior and clinical importance in CHB remain elusive. One hundred and twenty CHB patients and forty healthy controls (HCs) were enrolled, and the serum sRAGE as well as RAGE expression in biopsy specimens from these subjects was analyzed, and correlation of sRAGE with clinical features as well as its potential predictive value for monitoring the CHB was also evaluated. Reduced serum sRAGE levels and decreased tissular RAGE expression were observed in CHB patients. sRAGE and RAGE were inversely correlated with gradually increased grades of hepatic necroinflammation as well as the routine indicator ALT. Furthermore, receiver operating characteristic (ROC) analysis showed that combination of ALT and sRAGE exerted better predictive power (area under the ROC curve (AUC) of 0.86) for hepatic necroinflammation than that of ALT (AUC of 0.82), sRAGE (AUC of 0.81), or sRAGE-to-ALT ratio (sRAGE/ALT) (AUC of 0.85) alone. More importantly, circulating sRAGE alone exerted valuable predictive power for hepatic moderate-to-severe necroinflammation in CHB patients but with normal ALT (AUC of 0.81) or minimally elevated ALT (AUC of 0.85). In conclusion, reduced serum sRAGE levels may imply an increased severity for necroinflammation, and it may serve as a potential alternative biomarker for monitoring hepatic necroinflammation in CHB.

A rapid construction of new boron heterocycles and evaluation of photophysical properties of iminoboronates.

A green and efficient method for the synthesis of oxadiazaborole, dioxazaborinine, and oxadiazaborinine from the reactions of phenylboronic acid with amidoxime, α-hydroxyl oxime and α-hydroxyl hydrazone, respectively, is described. The reactions were performed under catalyst-free and mild conditions. All products can be rapidly purified by filtration and washing. In addition, a set of iminoboronates were prepared following a one-pot multicomponent reaction procedure using α-hydroxyl hydrazone, salicylaldehyde and boronic acid derivatives as starting materials and their photophysical properties were assessed. Then, cross-coupling reactions can be carried out smoothly on some target compounds, which may help develop new boron masking strategies.

Imidazole Hydrochloride Promoted Synthesis of Nitriles from Aldehydes.

BACKGROUND AND OBJECTIVE: As a key pharmacophore, the cyano group widely exists in a variety of biologically active compounds. Besides, nitriles are also valuable intermediates for many common functional groups. In this current work, a new synthesis strategy was developed to obtain nitriles from aldehydes. METHODS: Using commercially available aldehydes as raw materials, and hydroxylamine and hydrochloride as nitrogen sources, the corresponding nitrile compounds were successfully synthesized by the one-pot method through the promotion of imidazole hydrochloride. And it was characterized by 1H NMR, 13C NMR, and mass spectrometry. RESULTS: Various reaction conditions were applied in order to find an optimum and convenient procedure for the formation of nitriles. The highest yields (95%) were achieved using sulfolane as a solvent, and imidazole hydrochloride as a promoter. CONCLUSION: In conclusion, we developed a new synthetic method for nitrile compounds from aldehydes. Twenty seven examples of functionalized nitrile compounds have been synthesized in good to excellent yields. This methodology features that an environmentally benign imidazole hydrochloride replaces transition metal catalysts and oxidants required in conventional strategies to convert aldehydes into nitriles with good functional group tolerability. Further exploration of imidazole hydrochloride is ongoing in our laboratory.

Geosmithia Species Associated With Bark Beetles From China, With the Description of Nine New Species.

Fungi of the genus Geosmithia are frequently associated with bark beetles that feed on phloem on various woody hosts. Most studies on Geosmithia were carried out in North and South America and Europe, with only two species being reported from Taiwan, China. This study aimed to investigate the diversity of Geosmithia species in China. Field surveys in Fujian, Guangdong, Guangxi, Hunan, Jiangsu, Jiangxi, Shandong, Shanghai, and Yunnan yielded a total of 178 Geosmithia isolates from 12 beetle species. The isolates were grouped based on morphology. The internal transcribed spacer, ß-tubulin, and elongation factor 1-α gene regions of the representatives of each group were sequenced. Phylogenetic trees were constructed based on those sequences. In total, 12 species were identified, with three previously described species (Geosmithia xerotolerans, G. putterillii, and G. pallida) and nine new species which are described in this paper as G. luteobrunnea, G. radiata, G. brevistipitata, G. bombycina, G. granulata (Geosmithia sp. 20), G. subfulva, G. pulverea (G. sp. 3 and Geosmithia sp. 23), G. fusca, and G. pumila sp. nov. The dominant species obtained in this study were G. luteobrunnea and G. pulverea. This study systematically studied the Geosmithia species in China and made an important contribution to filling in the gaps in our understanding of global Geosmithia species diversity.

Mechanical Properties of GaN Single Crystals upon C Ion Irradiation: Nanoindentation Analysis.

Mechanical properties of gallium nitride (GaN) single crystals upon carbon ion irradiation are examined using nanoindentation analysis at room temperature. Pop-in events in the load-depth curves are observed for unirradiated and irradiated GaN samples. A statistical linear relationship between the critical indentation load for the occurrence of the pop-in event and the associated displacement jump is exhibited. Both the slope of linear regression and the measured hardness increase monotonically to the ion fluence, which can be described by logistic equations. Moreover, a linear relationship between the regression slope as a micromechanical characterization and the hardness as a macroscopic mechanical property is constructed. It is also found that the maximum resolved shear stress of the irradiated samples is larger than that of the unirradiated samples, as the dislocation loops are pinned by the irradiation-induced defects. Our results indicate that the nanoindentation pop-in phenomenon combined with a statistical analysis can serve as a characterization method for the mechanical properties of ion-irradiated materials.

Adaptive Neural Digital Control of Hysteretic Systems With Implicit Inverse Compensator and Its Application on Magnetostrictive Actuator.

Hysteresis is a complex nonlinear effect in smart materials-based actuators, which degrades the positioning performance of the actuator, especially when the hysteresis shows asymmetric characteristics. In order to mitigate the asymmetric hysteresis effect, an adaptive neural digital dynamic surface control (DSC) scheme with the implicit inverse compensator is developed in this article. The implicit inverse compensator for the purpose of compensating for the hysteresis effect is applied to find the compensation signal by searching the optimal control laws from the hysteresis output, which avoids the construction of the inverse hysteresis model. The adaptive neural digital controller is achieved by using a discrete-time neural network controller to realize the discretization of time and quantizing the control signal to realize the discretization of the amplitude. The adaptive neural digital controller ensures the semiglobally uniformly ultimately bounded (SUUB) of all signals in the closed-loop control system. The effectiveness of the proposed approach is validated via the magnetostrictive-actuated system.

Ophiostomatoid species associated with pine trees (Pinus spp.) infested by Cryphaluspiceae from eastern China, including five new species.

Cryphaluspiceae attacks various economically important conifers. Similar to other bark beetles, Cr.piceae plays a role as a vector for an assortment of fungi and nematodes. Previously, several ophiostomatoid fungi were isolated from Cr.piceae in Poland and Japan. In the present study, we explored the diversity of ophiostomatoid fungi associated with Cr.piceae infesting pines in the Shandong Province of China. We isolated ophiostomatoid fungi from both galleries and beetles collected from our study sites. These fungal isolates were identified using both molecular and morphological data. In this study, we recovered 175 isolates of ophiostomatoid fungi representing seven species. Ophiostomaips was the most frequently isolated species. Molecular and morphological data indicated that five ophiostomatoid fungal species recovered were previously undescribed. Thus, we proposed these five novel species as Ceratocystiopsisyantaiensis, C.weihaiensis, Graphilbumtranslucens, Gr.niveum, and Sporothrixvillosa. These new ophiostomatoid fungi add to the increasing number of fungi known from China, and this evidence suggests that numerous novel taxa are awaiting discovery in other forests of China.

Compound Adaptive Fuzzy Quantized Control for Quadrotor and Its Experimental Verification.

This article aims to realize a precise position and attitude tracking control for the quadrotor using a proposed fuzzy approximator-based compound adaptive fuzzy quantized control scheme. In the control scheme, a quantized output-feedback control for position tracking and a state-feedback quantized control for attitude trajectory tracking are combined to deal with the underactuated and strong coupling problems of the quadrotor. The main contributions are: 1) the adaptive fuzzy quantized control is realized, then the strong nonlinearities caused by the quantizer are effectively mitigated, which implies that the control precision can be improved when a low communication rate is required in the real-time control system of quadrotor; 2) by applying the adaptive fuzzy dynamic surface control (DSC) technique to the underactuated quadrotor control system, the "explosion of complexity" problem in the backstepping method is overcome and the L∞ tracking performance is achieved with the proposed initializing technique inspired by Zhang et al. This guarantees that the attitude signals promptly converge to the desired trajectories, then the underactuated problem of the quadrotor is overcome by solving the designed adaptive fuzzy-quantized control equations; and 3) the experiments on the platform of the Quanser Qball-X4 quadrotor are conducted and the effectiveness of the proposed control scheme is validated.

Adaptive fuzzy dynamic surface sliding mode control of large-scale power systems with prescribe output tracking performance.

This paper focuses on an adaptive fuzzy based dynamic surface sliding mode control (ADSSMC) strategy for multi-machine power systems with SVC. The main characteristics of the proposed ADSSMC strategy are: (1) System robustness and the convergency speed of all surface error are enhanced by combining dynamic surface control with sliding mode, leading to the structural complexity of the controller in backstepping control scheme is eliminated; (2) By introducing an error performance conversion function, the errors of desired trajectory and system output are always within a predetermined range; (3) In the adaptive regulation laws, the number of estimated parameters of the control system is significantly reduced due to the utilization of the estimations of weight vector norm instead of the weight vectors itself. The stability analysis proves that the proposed ADSSMC control strategy can guarantee the boundaries of all signals in the closed-loop control system. Experimental results verify the effectiveness of the proposed ADSSMC scheme.