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The health condition of hoisting gearbox bearings of quay cranes is of great importance for the safety of port production. A remaining useful life (RUL) predicting framework for lifting gearbox bearings of quay crane under time-varying operating conditions is proposed. First, the working load is discretized and the condition boundaries are determined. Then, the long short-term memory (LSTM) network model is adopted to predict the load and the corresponding operating conditions. Afterwards, considering the degradation rates and jump coefficients under different operating conditions, the state degradation function is established based on the Wiener process. Finally, the condition-activated particle filter (CAPF) is used to predict the degradation state and RUL of bearings. The proposed prediction framework is verified by the full-life data of the hoisting gearbox bearings in a port in Shanghai collected by the NetCMAS system. A comparison with the other three prediction methods shows that the proposed framework is able to obtain more accurate degradation states and RUL predictions under time-varying operating conditions.

Abstract Background Spinal cord injury (SCI) is a common trauma in clinical practices. Subacute SCI is mainly characterized by neuronal apoptosis, axonal demyelination, Wallerian degeneration, axonal remodeling, and glial scar formation. It has been discovered in recent years that inflammatory responses are particularly important in subacute SCI. However, the mechanisms mediating inflammation are not completely clear. Methods The gene expression profiles of GSE20907, GSE45006, and GSE45550 were downloaded from the GEO database. The models of the three gene expression profiles were all for SCI to the thoracic segment of the rat. The differentially expressed genes (DEGs) and weighted correlation network analysis (WGCNA) were performed using R software, and functional enrichment analysis and protein–protein interaction (PPI) network were performed using Metascape. Module analysis was performed using Cytoscape. Finally, the relative mRNA expression level of central genes was verified by RT-PCR. Results A total of 206 candidate genes were identified, including 164 up-regulated genes and 42 down-regulated genes. The PPI network was evaluated, and the candidate genes enrichment results were mainly related to the production of tumor necrosis factors and innate immune regulatory response. Twelve core genes were identified, including 10 up-regulated genes and 2 down-regulated genes. Finally, seven hub genes with statistical significance in both the RT-PCR results and expression matrix were identified, namely Itgb1, Ptprc, Cd63, Lgals3, Vav1, Shc1, and Casp4. They are all related to the activation process of microglia. Conclusion In this study, we identified the hub genes and signaling pathways involved in subacute SCI using bioinformatics methods, which may provide a molecular basis for the future treatment of SCI.

A perforated leakage occurred in a gas field sewage storage tank in service. In order to analyze the cause of the perforation and to clarify the critical wall thicknesses of the common perforated points of the sewage storage tank, the micro hardness tester, universal testing machine, metallurgical microscope, scanning electron microscope (SEM), energy spectrometer (EDS) and X - ray diffraction (XRD) were used to analyze the physical and chemical properties of the storage tank, perforation characteristics, the morphology and composition of corrosion products. Results showed that the physical and chemical properties of the material met the requirements; the corrosion products were loose, mainly containing Fe2O3 and having a small amount of FeS. The corrosion pit developed from the inner wall of the storage tank to the outer wall, and the depth of the corrosion pit was about 2.6 mm. Therefore, the perforation mechanism and process of the storage tank could be destribed as follow: the water and corrosive medium penetrated between the layer and the inner wall of the storage tank, leading to an oxygen corrosion (the main corrosion) and a SRB corrosion (the auxiliary corrosion), and as a result, local corrosion pits formed on the inner wall of the storage tank. When the depth of the corrosion pit reached 65% of the initial wall thickness of the storage tank, the stress level at the bottom of the pit exceeded the internal pressure resistance of the storage tank, resulting in a perforation leakage of the storage tank.

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Planting vegetation in the dry-hot valley region of South-western China has proven to be an effective measure for controlling the development of gullies. However, the mechanisms responsible for this effectiveness remain unclear. In this study, five plots, each containing a different herbaceous species, were chosen to explore the effects of their root morphological characteristics on soil shear strength and soil anti-scourability. Our results showed a significant difference among the root morphological characteristics of the five species. In addition, the soil shear strengths of the vegetated plots were greater than that of the bare plot. This study demonstrated a significant positive correlation for root weight density among the different plots. Moreover, the runoff sediment was logarithmically related to time, and the root volume density was linearly related to soil anti-scourability, although exponentially related to soil detachment rate. These findings improve the understanding of the effects of different root morphological characteristics on soil shear strength and soil anti-scourability. We expect that these research results will provide a theoretical background for further study of plant species selection during the practice of soil and water conservation in the dry-hot valley region of South-western China. Additional keywords: dry-hot valley region, gully erosion, root morphological characteristics, soil anti-scourability. Received 7 November 2018, accepted 15 October 2019, published online 19 November 2019, Introduction As a vital component of vegetation restoration measures, herbaceous species can reduce the amount of runoff via its thick foliage as well as decrease the kinetic energy of raindrops, [...]

To develop the structural and functional modeling chemistry of [NiFe]-H2ases, we have carried out a study regarding the synthesis, structural characterization and reactivity of a new series of [NiFe]-H2ase model complexes. Thus, treatment of diphosphine dppb-chelated Ni complex (dppb)NiCl2 (dppb = 1,2-(Ph2P)2C6H4) with (dppv)Fe(CO)2(pdt) (dppv = 1,2-(Ph2P)2C2H2, pdt = 1,3-propanedithiolate) and NaBF4 gave dicarbonyl complex [(dppb)Ni(pdt)Fe(CO)2(dppv)](BF4)2 ([A](BF4)2). Further treatment of [A](BF4)2 with Me3NO and Bu4NCN or KSCN afforded t-cyanido and t-isothiocyanato complexes [(dppb)Ni(pdt)Fe(CO)(t-R)(dppv)]BF4 ([1]BF4, R = CN; [2]BF4, R = NCS), respectively. While azadiphosphine MeN(CH2PPh2)2-chelated t-hydride complex [MeN(CH2PPh2)2Ni(pdt)Fe(CO)(t-H)(dppv)]BF4 ([3]BF4) was prepared by treatment of dicarbonyl complex [MeN(CH2PPh2)2Ni(pdt)Fe(CO)2(dppv)](BF4)2 ([B](BF4)2) with Me3NO and 1.5 MPa of H2, treatment of dicarbonyl complex [B](BF4)2 with Me3NO (without H2) in pyridine resulted in formation of a novel monocarbonyl complex [MeN(CH2PPh2)2Ni(SCHCH2CH2S)Fe(CO)(dppv)]BF4 ([4]BF4) via the unexpected sp3 C-H bond activation reaction. Furthermore, azadiphosphine PhN(CH2PPh2)2-chelated µ-mercapto complex [PhN(CH2PPh2)2Ni(pdt)Fe(CO)(µ-SH)(dppv)]BF4 ([5]BF4) was prepared by treatment of dicarbonyl complex [PhN(CH2PPh2)2Ni(pdt)Fe(CO)2(dppv)](BF4)2 ([C](BF4)2) with Me3NO and H2S gas, whereas treatment of azadiphosphine Ph2CHN(CH2PPh2)2-chelated dicarbonyl complex [Ph2CHN(CH2PPh2)2Ni(pdt)Fe(CO)2(dppe)](BF4)2 ([D](BF4)2, dppe = 1,2-(Ph2P)2C2H4) with Me3NO⋅2H2O gave rise to µ-hydroxo complex [Ph2CHN(CH2PPh2)2Ni(pdt)Fe(CO)(µ-OH)(dppe)]BF4 ([6]BF4). All the possible pathways for formation of the new model complexes are briefly discussed, and their structures were fully characterized by various spectroscopic techniques and for six of them by X-ray crystallography.

Bearings are the core components of ship propulsion shafting, and effective prediction of their working condition is crucial for reliable operation of the shaft system. Shafting vibration signals can accurately represent the running condition of bearings. Therefore, in this article, we propose a new model that can reliably predict the vibration signal of bearings. The proposed method is a combination of a fuzzy-modified Markov model with gray error based on particle swarm optimization (PGFM (1,1)). First, particle swarm optimization was used to optimize and analyze the three related parameters in the gray model (GM (1,1)) that affect the data fitting accuracy, to improve the data fitting ability of GM (1,1) and form a GM (1,1) based on particle swarm optimization, which is called PGM (1,1). Second, considering that the influence of historical relative errors generated by data fitting on subsequent data prediction cannot be expressed quantitatively, the fuzzy mathematical theory was introduced to make fuzzy corrections to the historical errors. Finally, a Markov model is combined to predict the next development state of bearing vibration signals and form the PGFM (1,1). In this study, the traditional predictions of GM (1,1), PGM (1,1), and newly proposed PGFM (1,1) are carried out on the same set of bearing vibration data, to make up for the defects of the original model layer by layer and form a set of perfect forecast system models. The results show that the predictions of PGM (1,1) and PGFM (1,1) are more accurate and reliable than the original GM (1,1). Hence, they can be helpful in the design of practical engineering equipment.

Copyright of Journal of Fish Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the process of developing offshore wind power towards deeper waters, the advantages of the bucket foundation in terms of integrated construction and economy are becoming increasingly evident. In contrast to conventional floating bodies, the air-floating bucket foundations can achieve self-floating with the help of the air in the compartment and adjust its buoyancy and stability by controlling the air volume in the compartment. The construction process of the bucket foundation involves the control of air in the compartment, thus making it more difficult to construct. Especially after the prefabrication of the bucket foundation, the stability of the bucket foundation at the floating-up stage is particularly critical. The stability of a multi-compartment bucket foundation during the floating-up process cannot be accurately evaluated as the existing theoretical method of air-floating structures does not adequately consider air compressibility. To ensure the safety of the floating-up process, a theoretical method based on the idea of intact stability has been developed to analyze the stability of the air-floating bucket foundations, which will allow accurate calculation of the righting arm for different tilt states and critical air leakage angle. At the same time, accuracy and feasibility of the proposed theoretical method are verified through indoor model tests and practical operation of the prototype structure during the floating-up process. In addition, measures to enhance the stability of the bucket foundation are proposed through sensitivity analysis of influencing factors. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is a major social problem with a heavy burden on patient physiology and psychology. Glial scar formation and irreversible neuron loss are the two key points during SCI progression. During the acute phase of spinal cord injury, glial scars form, limiting the progression of inflammation. However, in the subacute or chronic phase, glial scarring inhibits axon regeneration. Following spinal cord injury, irreversible loss of neurons leads to further aggravation of spinal cord injury. Several therapies have been developed to improve either glial scar or neuron loss; however, few therapies reach the stage of clinical trials and there are no mainstream therapies for SCI. Exploring the key mechanism of SCI is crucial for finding further treatments. Glycogen synthase kinase-3 (GSK-3) is a widely expressed kinase with important physiological and pathophysiological functions in vivo. Dysfunction of the GSK-3 signaling pathway during SCI has been widely discussed for controlling neurite growth in vitro and in vivo, improving the proliferation and neuronal differentiation of endogenous neural stem cells and functional recovery from spinal cord injury. SCI can decrease the phosphorylated (p)/total (t)-GSK-3β ratio, which leads to an increase in apoptosis, whereas treatment with GSK-3 inhibitors can promote neurogenesis. In addition, several therapies for the treatment of SCI involve signaling pathways associated with GSK-3. Furthermore, signaling pathways associated with GSK-3 also participate in the pathological process of neuropathic pain that remains following SCI. The present review summarized the roles of GSK-3 signaling in SCI to aid in the understanding of GSK-3 signaling during the pathological processes of SCI and to provide evidence for the development of comprehensive treatments. [ABSTRACT FROM AUTHOR]

Leaf photosynthetic nitrogen‐use efficiency (PNUE) diversified significantly among C3 species. To date, the morpho‐physiological mechanisms and interrelationships shaping PNUE on an evolutionary time scale remain unclear. In this study, we assembled a comprehensive matrix of leaf morpho‐anatomical and physiological traits for 679 C3 species, ranging from bryophytes to angiosperms, to comprehend the complexity of interrelationships underpinning PNUE variations. We discovered that leaf mass per area (LMA), mesophyll cell wall thickness (Tcwm), Rubisco N allocation fraction (PR), and mesophyll conductance (gm) together explained 83% of PNUE variations, with PR and gm accounting for 65% of those variations. However, the PR effects were species‐dependent on gm, meaning the contribution of PR on PNUE was substantially significant in high‐gm species compared to low‐gm species. Standard major axis (SMA) and path analyses revealed a weak correlation between PNUE and LMA (r2 = 0.1), while the SMA correlation for PNUE–Tcwm was robust (r2 = 0.61). PR was inversely related to Tcwm, paralleling the relationship between gm and Tcwm, resulting in the internal CO2 drawdown being only weakly proportional to Tcwm. The coordination of PR and gm in relation to Tcwm constrains PNUE during the course of evolution. Summary Statement: Leaf photosynthetic nitrogen‐use efficiency (PNUE) varies significantly among major phylogenetic clades and species. Numerous studies have examined the variations in PNUE among major plant groups, attributing these variations to leaf habits or height‐related economic spectra, microhabitat acclimations, or unknown fundamental differences. Results from a comprehensive matrix of leaf morpho‐anatomical and physiological traits for 679 C3 species discovered that cell wall thickness (Tmcw) has phylogenetically consistent effects on PNUE of terrestrial plants. [ABSTRACT FROM AUTHOR]

A new type of metal-free [5+1] cycloaddition reaction of donor–acceptor aziridines with 2-(2-isocyanoethyl)indoles is reported herein. This method exhibits broad substrate scope and atom-economy. A series of 2H-1,4-oxazines containing an indole heterocycle skeleton were obtained in up to 92% yield under mild reaction conditions. Control experiments revealed that free indole N–H is crucial for the above transformations. The theoretical calculation studies provided guidance on the in-depth insight into the reaction mechanism and the hydrogen-bond between the free indole N–H and carbonyl group was identified to lower the free energy barrier in the transition states. [ABSTRACT FROM AUTHOR]

Mahu conglomerate oilfield has strong heterogeneity. Currently, large-scale hydraulic fracturing is commonly used for reservoir reconstruction. The geometry of hydraulic fractures is influenced by gravel. By referring to the scanning and logging results of a conglomerate reservoir, and considering the characteristics of gravel development in the Mahu Oilfield reservoir, python programming is used to establish a finite element model containing a matrix, bonding interface, and gravel, which considers the random distribution of gravel position and size. The model uses cohesive element global embedding to study the geometry of a hydraulic fracture. The results show that the hydraulic fracture in the gravel reservoir mainly spreads around the gravel, and the propagation path of the hydraulic fracture is affected by the horizontal stress difference. When the interfacial bonding strength is greater than 2 MPa, the conglomerate is more likely to be penetrated by hydraulic fractures, or the hydraulic fractures stop expanding after entering the conglomerate. The strength of the conglomerate largely determines whether hydraulic fractures can pass through it. When the strength of gravel is greater than 7 MPa, hydraulic fractures will stop expanding after entering the gravel. During the hydraulic fracturing process of conglomerate reservoirs, using a large injection rate can result in longer hydraulic fractures and larger fracture volumes. [ABSTRACT FROM AUTHOR]