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Abstract This study investigates the prediction of ground loss rate during soft-soil shield tunneling using Peck’s back analysis method and XGBoost model. Bayesian optimization is employed to determine optimal hyperparameters, ensuring comprehensive and efficient model tuning. The XGBoost model is compared with Random Forest (RF) and Support Vector Machine (SVM) models to benchmark its performance. The results demonstrate the superior accuracy and robustness of the XGBoost model. Also, the results show that the soil properties and the grouting factors of the excavation face affect the duration of the instantaneous settlement of the ground surface. There is a specific correlation between the depth-to-diameter ratio, the coefficient of variation in the advancing speed of the shield machine, the maximum surface subsidence, and the ground loss rate. The prediction model of the ground loss rate based on the combined approach of Peck back analysis and eXtreme Gradient Boosting and Bayesian optimization has high reliability in soft-soil layers, and this method can provide a specific reference for predicting construction risk in related projects.

Abstract This study proposes a smart grid model named “GridOptiPredict”, which aims to achieve efficient analysis and processing of power system data through deep fusion of deep learning and graph neural network, so as to improve the intelligent level and overall efficiency of power grid operation. The model integrates three core functions of load forecasting, power grid state sensing and resource optimization into one, forming a closely connected and complementary framework. Through carefully designed experimental scheme, the practical value and effectiveness of “Grid OptiPredict” model are fully verified from three aspects: accuracy of load forecasting, sensitivity of power grid state sensing and efficiency of resource allocation strategy. Experimental results show that the model has significant advantages in prediction accuracy, model stability and robustness, resource optimization, security, information security, social and economic benefits and user experience.

Abstract Esterases are crucial biocatalysts in chiral compound synthesis. Herein, a novel esterase EstSIT01 belonging to family V was identified from Microbacterium chocolatum SIT101 through genome mining and phylogenetic analysis. EstSIT01 demonstrated remarkable efficiency in asymmetrically hydrolyzing meso-dimethyl ester [Dimethyl cis-1,3-Dibenzyl-2-imidazolidine-4,5-dicarboxyate], producing over 99% yield and 99% enantiomeric excess (e.e.) for (4S, 5R)-monomethyl ester, a crucial chiral intermediate during the synthesis of d-biotin. Notably, the recombinant E. coli expressing EstSIT01 exhibited over 40-fold higher activity than that of the wild strain. EstSIT01 displays a preference for short-chain p-NP esters. The optimal temperature and pH were 45 °C and 10.0, with K m and k cat values of 0.147 mmol/L and 5.808 s− 1, respectively. Molecular docking and MD simulations suggest that the high stereoselectivity for meso-diester may attribute to the narrow entrance tunnel and unique binding pocket structure. Collectively, EstSIT01 holds great potential for preparing chiral carboxylic acids and esters.

The rapid expansion of e-commerce, particularly in the clothing sector, has led to a significant demand for an effective clothing industry. This study presents a novel two-stage image recognition method. Our approach distinctively combines human keypoint detection, object detection, and classification methods into a two-stage structure. Initially, we utilize open-source libraries, namely OpenPose and Dlib, for accurate human keypoint detection, followed by a custom cropping logic for extracting body part boxes. In the second stage, we employ a blend of Harris Corner, Canny Edge, and skin pixel detection integrated with VGG16 and support vector machine (SVM) models. This configuration allows the bounding boxes to identify ten unique attributes, encompassing facial features and detailed aspects of clothing. Conclusively, the experiment yielded an overall recognition accuracy of 81.4% for tops and 85.72% for bottoms, highlighting the efficacy of the applied methodologies in garment categorization.

The Ensemble Kalman filter (EnKF) is a classic method of data assimilation. For distributed sampling, the conventional EnKF usually requires a centralized server to integrate the predictions of all particles or a fully-connected communication network, causing traffic jams and low bandwidth utilization in high-performance computing. In this paper, we propose a novel distributed scheme of EnKF based on network setting of sampling, called Particle Network EnKF. Without a central server, every sampling particle communicates with its neighbors over a sparsely connected network. Unlike the existing work, this method focuses on the distribution of sampling particles instead of sensors and has been proved effective and robust on numerous tasks. The numerical experiments on the Lorenz-63 and Lorenz-96 systems indicate that, with proper communication rounds, even on a sparse particle network, this method achieves a comparable performance to the standard EnKF. A detailed analysis of effects of the network topology and communication rounds is performed. Another experiment demonstrating a trade-off between the particle homogeneity and performance is also provided. The experiments on the whole-brain neuronal network model show promises for applications in large-scale assimilation problems.

Abstract Microglia are the resident immune cells in the central nervous system (CNS), which play important roles in the repair of neuroinflammatory injury. The present study investigated the anti-neuroinflammatory effects of vinpocetine induced by lipopolysaccharide (LPS) in BV2 microglia. BV2 microglia were pretreated with vinpocetine, and then stimulated with LPS (100 ng/mL). The cytotoxicity of BV2 microglia was assessed by MTT assay. The expression levels of nitrite oxide were measured by Griess assay. Proinflammatory cytokines and mediators were determined by Western blot, ELISA, or quantitative real-time PCR. Vinpocetine significantly decreased the generation of nitric oxide-inducible nitric oxide synthase (iNOS), cyclooxygenase- (COX-) 2 in a dose-dependent manner. In addition, vinpocetine decreased the production of pro-inflammatory cytokines such as tumor necrosis factor alpha (TNF-α), interleukin (IL)-6 and IL-1β. Furthermore, it was observed that phosphorylation levels of AMPK (Thr-172) decreased in LPS-stimulated BV2 microglia. Vinpocetine treatment increased AMPK phosphorylation in LPS-stimulated BV2 microglia. AMPK inhibition by siRNA blocked the anti-inflammatory effects of vinpocetine induced by LPS in BV2 microglia. The overall results demonstrate that vinpocetine has anti-inflammatory effects on LPS-stimulated BV2 microglia via inducing phosphorylation of AMPK, suggesting that vinpocetine is a potential therapeutic agent in neuroinflammatory injury.

The venom of various Conus species is composed of a rich variety of unique bioactive peptides, commonly referred to as conotoxins (conopeptides). Most conopeptides have specific receptors or ion channels as physiologically relevant targets. In this paper, high-throughput transcriptome sequencing was performed to analyze putative conotoxin transcripts from the venom duct of a vermivorous cone snail species, Conus litteratus native to the South China Sea. A total of 128 putative conotoxins were identified, most of them belonging to 22 known superfamilies, with 43 conotoxins being regarded as belonging to new superfamilies. Notably, the M superfamily was the most abundant in conotoxins among the known superfamilies. A total of 15 known cysteine frameworks were also described. The largest proportion of cysteine frameworks were VI/VII (C-C-CC-C-C), IX (C-C-C-C-C-C) and XIV (C-C-C-C). In addition, five novel cysteine patterns were also discovered. Simple sequence repeat detection results showed that di-nucleotide was the major type of repetition, and the codon usage bias results indicated that the codon usage bias of the conotoxin genes was weak, but the M, O1, O2 superfamilies differed in codon preference. Gene cloning indicated that there was no intron in conotoxins of the B1- or J superfamily, one intron with 1273–1339 bp existed in a mature region of the F superfamily, which is different from the previously reported gene structure of conotoxins from other superfamilies. This study will enhance our understanding of conotoxin diversity, and the new conotoxins discovered in this paper will provide more potential candidates for the development of pharmacological probes and marine peptide drugs.

Considering the problems in the discrimination of fracture penetration and the evaluation of fracturing performance in the stimulation of thin sand-mud interbedded reservoirs in the eighth member of Shihezi Formation of Permian (He-8 Member) in the Sulige gas field, a geomechanical model of thin sand-mud interbedded reservoirs considering interlayer heterogeneity was established. The experiment of hydraulic fracture penetration was performed to reveal the mechanism of initiation–extension–interaction–penetration of hydraulic fractures in the thin sand-mud interbedded reservoirs. The unconventional fracture model was used to clarify the vertical initiation and extension characteristics of fractures in thin interbedded reservoirs through numerical simulation. The fracture penetration discrimination criterion and the fracturing performance evaluation method were developed. The results show that the interlayer stress difference is the main geological factor that directly affects the fracture morphology during hydraulic fracturing. When the interlayer stress difference coefficient is less than 0.4 in the Sulige gas field, the fractures can penetrate the barrier and extend in the target sandstone layer. When the interlayer stress difference coefficient is not less than 0.4 and less than 0.45, the factures can penetrate the barrier but cannot extend in the target sandstone layers. When the interlayer stress difference coefficient is greater than 0.45, the fractures only extend in the perforated reservoir, but not penetrate the layers. Increasing the viscosity and pump rates of the fracturing fluid can compensate for the energy loss and break through the barrier limit. The injection of high viscosity (50–100 mPa·s) fracturing fluid at high pump rates (12–18 m3/min) is conducive to fracture penetration in the thin sand-mud interbedded reservoirs in the Sulige gas field.

Abstract Background The understanding of the heterogeneous cellular microenvironment of colonic polyps in paediatric patients with solitary juvenile polyps (SJPs), polyposis syndrome (PJS) and Peutz–Jeghers syndrome (PJS) remains limited. Methods We conducted single‐cell RNA sequencing and multiplexed immunohistochemistry (mIHC) analyses on both normal colonic tissue and different types of colonic polyps obtained from paediatric patients. Results We identified both shared and disease‐specific cell subsets and expression patterns that played important roles in shaping the unique cellular microenvironments observed in each polyp subtype. As such, increased myeloid, endothelial and epithelial cells were the most prominent features of SJP, JPS and PJS polyps, respectively. Noticeably, memory B cells were increased, and a cluster of epithelial–mesenchymal transition (EMT)‐like colonocytes existed across all polyp subtypes. Abundant neutrophil infiltration was observed in SJP polyps, while CX3CR1hi CD8+ T cells and regulatory T cells (Tregs) were predominant in SJP and JPS polyps, while GZMAhi natural killer T cells were predominant in PJS polyps. Compared with normal colonic tissues, myeloid cells exhibited specific induction of genes involved in chemotaxis and interferon‐related pathways in SJP polyps, whereas fibroblasts in JPS polyps had upregulation of myofiber‐associated genes and epithelial cells in PJS polyps exhibited induction of a series of nutrient absorption‐related genes. In addition, the TNF‐α response was uniformly upregulated in most cell subsets across all polyp subtypes, while endothelial cells and fibroblasts separately showed upregulated cell adhesion and EMT signalling in SJP and JPS polyps. Cell–cell interaction network analysis showed markedly enhanced intercellular communication, such as TNF, VEGF, CXCL and collagen signalling networks, among most cell subsets in polyps, especially SJP and JPS polyps. Conclusion These findings strengthen our understanding of the heterogeneous cellular microenvironment of polyp subtypes and identify potential therapeutic approaches to reduce the recurrence of polyps in children.

As solitary filter feeder, Styela clava shows superior water purification capacity in the integrated multi-trophic aquaculture (IMTA) model consisting of S. clava, microalgae, and sea cucumber, which should be an ideal system to reduce organic and inorganic pollution in the water. It is of great significance to study the physiological energetics of S. clava for the application of this IMTA system. The physiological energetics of S. clava was determined in a simulated natural culture system to provide information for comparing to the energetic data derived from feeding ecological studies. The ascidians were grouped into five cohorts based on body size in terms of their wet weight of 1.5-2.0 g, 2.5-3.5 g, 5.0-6.5 g, 8.0-9.5 g, and 11.0-14.0 g, respectively. Clearance rate (CR), ingestion rate (IR), and assimilation efficiency (AE) of ascidian were estimated using flow-through feeding chambers. The results showed that the CR and IR increased exponentially with the ascidians' body size at different temperatures. Body size showed little effect on AE at the same water temperature. However, significant differences were observed between different temperature regions in the range of 12-28°C regardless of body size. S. clava performed far better in feeding behavior at 20°C than that at higher or lower temperatures. Within the range of diet concentration (as particulate organic matter, POM) from 2.11 to 6.11 mg POM/L, the CR and IR increased exponentially with POM. This study provides basic data for the application of ascidian in the IMTA system. [ABSTRACT FROM AUTHOR]

ImportanceThe number of infections and deaths caused by the global epidemic of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) invasion is steadily increasing daily. In the early stages of outbreak, approximately 15%–20% of patients with coronavirus disease 2019 (COVID-19) inevitably developed severe and critically ill forms of the disease, especially elderly patients and those with several or serious comorbidities. These more severe forms of disease mainly manifest as dyspnea, reduced blood oxygen saturation, severe pneumonia, acute respiratory distress syndrome (ARDS), thus requiring prolonged advanced respiratory support, including high-flow nasal cannula (HFNC), non-invasive mechanical ventilation (NIMV), and invasive mechanical ventilation (IMV).ObjectiveThis study aimed to propose a safer and more practical tracheotomy in invasive mechanical ventilated patients with COVID-19.DesignThis is a single center quality improvement study.ParticipantsTracheotomy is a necessary and important step in airway management for COVID-19 patients with prolonged endotracheal intubation, IMV, failed extubation, and ventilator dependence. Standardized third-level protection measures and bulky personal protective equipment (PPE) may hugely impede the implementation of tracheotomy, especially when determining the optimal pre-surgical positioning for COVID-19 patients with ambiguous surface position, obesity, short neck or limited neck extension, due to vision impairment, reduced tactile sensation and motility associated with PPE. Consequently, the aim of this study was to propose a safer and more practical tracheotomy, namely percutaneous dilated tracheotomy (PDT) with delayed endotracheal intubation withdrawal under the guidance of bedside ultrasonography without the conventional use of flexible fiberoptic bronchoscopy (FFB), which can accurately determine the optimal pre-surgical positioning, as well as avoid intraoperative damage of the posterior tracheal wall and prevent the occurrence of tracheoesophageal fistula (TEF).

A novel microbial strain Microbacterium oxydans with high alcohol dehydrogenase (ADH) activity and enantioselectivity was isolated from soil, through an effective screening procedure in which rac-1-phenylethanol was supplied as the sole carbon and energy source. After series optimization of fermentation, the biosynthesis of the ADH in Microbacterium oxydans reached a maximum of 120 U/l at 30 h of cultivation and the activity retained for considerable time (5 days). In the gram preparative biooxidation of 50 mM rac-1-phenylethanol using resting cells of Microbacterium oxydans, (S)-(-)-1-phenylethanol (>99.5% enantiomeric excess (e.e.), 40.1% yield) and acetophenone (34.6% yield) were obtained, respectively. [ABSTRACT FROM AUTHOR]

In recent ten years, artificial bee colony (ABC) has attracted more and more attention, and many state-of-the-art ABC variants (ABCs) have been developed by introducing different biased information to the search equations. However, the same biased information is employed in employed bee and onlooker bee phases, which will cause over exploitation and lead to premature convergence. To overcome this limit, an effective framework with tristage adaptive biased learning is proposed for existing ABCs (TABL + ABCs). In TABL + ABCs, the search direction in the employed bee stage is guided by learning the ranking biased information of the parent food sources, while in the onlooker bee stage, the search direction is determined by extracting the biased information of population distribution. Moreover, a deletion-restart learning strategy is designed in scout bee stage to prevent the potential risk of population stagnation. Systematic experiment results conducted on CEC2014 competition benchmark suite show that proposed TABL + ABCs perform better than recently published AEL + ABCs and ACoS + ABCs.

Background: Osteoradionecrosis (ORN) of the cervical spine is a serious complication after radiotherapy (RT), which may show increased radiotracer uptake on a bone scan (BS) and be mistaken as metastasis. We aimed to assess the value of magnetic resonance imaging (MRI) in the differentiation of cervical spine ORN from bone metastasis after RT detected by BS in nasopharyngeal carcinoma (NPC).Methods: In this retrospective study, 35 NPC patients who had undergone RT were enrolled, of whom 21 patients showed cervical spine ORN and 14 showed bone metastasis. New areas of increased radiotracer uptake in the cervical spine on a BS were noted in all patients, following which the patients underwent neck MRI for further assessment. Two radiologists independently reviewed two sets of images including a BS set and an MRI set (MRI with BS) and reached a consensus. The diagnostic sensitivity, specificity, and accuracy for ORN detection were calculated, and interobserver agreement was evaluated using the kappa test.Results: A total of 75 cervical spine lesions were identified (44, ORN; 31 metastases). The BS set analysis showed that the diagnostic sensitivity, specificity, and accuracy were only 38.6, 48.3, and 42.7%, respectively, for differentiation of cervical spine ORN from bone metastasis. On the other hand, the MRI set analysis showed that the diagnostic sensitivity, specificity, and accuracy increased to 86.4, 90.3, and 88.0%, respectively. The interobserver agreement for the MRI set was determined to be very good (κ = 0.92).Conclusion: MRI is a reliable technique for the further discrimination of emerging cervical spine lesions after RT detected by BS. Furthermore, it could be a better differential diagnosis technique for distinguishing ORN from metastasis and may help avoid a wrong assignment of the patient to a metastatic stage with indication for treatment with supplemental toxicity and a subsequent palliative strategy.