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Although accumulating evidence indicates that endangered animals suffer from plastic pollution, this has been largely overlooked. Here, we explored the bacteria and eukaryotes living in the plastics gathered from the natural habitat of the highly endangered crocodile lizard. The results demonstrated that the bacterial and eukaryotic communities on plastics formed a unique ecosystem that exhibited lower diversity than those in the surrounding water and soil. However, microbes displayed a more complex and stable network on plastic than that in water or soil, implying unique mechanisms of stabilization. These mechanisms enhanced their resilience and contributed to the provision of stable ecological services. Eukaryotes formed a simpler and smaller network than bacteria, indicating different survival strategies. The bacteria residing on the plastics played a significant role in carbon transformation and sequestration, which likely impacted carbon cycling in the habitat. Furthermore, microbial exchange between plastics and the crocodile lizard was observed, suggesting that plastisphere serves as a mobile gene bank for the exchange of information, including potentially harmful substances. Overall, microbes on plastic appear to significantly impact the crocodile lizard and its natural habitat via various pathways. These results provided novel insights into risks evaluation of plastic pollution and valuable guidance for government efforts in plastic pollutant control in nature reserves.

Background:: Cerebellar intermittent theta burst stimulation (iTBS) modulates the excitability of the cerebral cortex and may enhance attentional performance. To date, few studies have conducted iTBS on healthy subjects for one week and used electroencephalography (EEG) to investigate the effect of multiple stimulation sessions on resting-state functional brain networks and the daily stimulation effect on attentional performance. Methods:: 16 healthy subjects participated in a one-week experiment, receiving bilateral cerebellar iTBS or sham stimulation and engaging in multi-task attentional training. The primary measures were the one-week attentional performance and pre- and post-experiment resting-state EEG activities. Amplitude Envelope Correlation (AEC) was used to construct the functional connectivity in the eye-open (EO) and eye-closed (EC) phases. Results:: At least three sessions of iTBS were required to enhance multi-task performance significantly, whereas only one or two sessions failed to elicit the improvement. Compared with the control group, iTBS induced significant changes in PSD, AEC functional connectivity, and AEC network properties during the EO phase, while it had little effect during the EC phase. During the EO phase, the network property changes of the iTBS subject were correlated with improved attentional performance. Conclusion:: The multi-task performance requires multiple stimulations to enhance. iTBS affects the resting-state alpha band brain activities during the EO rather than the EC phase. The AEC network properties may serve as a biomarker to assess the attentional potential of healthy subjects.

At present, an increasing number of small UAVs(Unmanned Aerial Vehicles) are commercialized and common, and the application of small UAVs has very good development prospects, such as UAV distribution services, UAV aerial photography services, and UAV formation performance. However, the misuse of small drones poses a significant threat. Lawbreakers use small drones equipped with various sensors to spy on personal privacy, steal corporate secrets, and threaten national conferences, which have had many adverse effects on society. In future wars, these small drones will perhaps be used on the battlefield along with high-end weapons. Therefore, it is necessary to find a solution for effectively identifying the basic information of UAV. For the existence of UAV and various small UAV types, this paper proposes a combination of RF sensing and target detection techniques with target detection algorithms to learn RF signal frequency frequency hopping features to detect UAV presence and identify the detected UAV. First, the RF signal of the UAV was obtained in real time by a software radio, and the time-frequency analysis of the short-time Fourier transform and wavelet transform is performed to generate frequency domain images with retained frequency hopping features. Then, the improved Yolov5-7.0 target detection model was employed for training, and finally, the trained model was used for identification and classification. The results showed that the method can effectively assist the detection and classification of UAVs that were obtained by identifying and classifying 5400 unlabeled images. The F1 score was 0.93, and the three assessment measures of P(Precision), R(Recall), and mAP(mean Average Precision) were 1.00, 1.00, and 0.967, respectively.

Abstract Background Recently, increasing data have suggested that the lncRNA small nucleolar RNA host genes (SNHGs) were aberrantly expressed in hepatocellular carcinoma (HCC), but the association between the prognosis of HCC and their expression remained unclear. The purpose of this meta‐analysis was to determine the prognostic significance of lncRNA SNHGs in HCC. Methods We systematically searched Embase, Web of Science, PubMed, and Cochrane Library for eligible articles published up to February 2024. The prognostic significance of SNHGs in HCC was evaluated by hazard ratios (HRs) and 95% confidence intervals (CIs). Odds ratios (ORs) were used to assess the clinicopathological features of SNHGs. Results This analysis comprised a total of 25 studies covering 2314 patients with HCC. The findings demonstrated that over‐expressed SNHGs were associated with larger tumor size, multiple tumor numbers, poor histologic grade, earlier lymphatic metastasis, vein invasion, advanced tumor stage, portal vein tumor thrombosis (PVTT), and higher alpha‐fetoprotein (AFP) level, but not with hepatitis B virus (HBV) infection, and cirrhosis. In terms of prognosis, patients with higher SNHG expression were more likely to have shorter overall survival (OS), relapse‐free survival (RFS), and disease‐free survival (DFS). Conclusions In conclusion, upregulation of SNHGs expression correlates with shorter OS, RFS, DFS, tumor size and numbers, histologic grade, lymphatic metastasis, vein invasion, tumor stage, PVTT, and AFP level, suggesting that SNHGs may serve as prognostic biomarkers in HCC.

The insulated and perfect conductivity problems arising from high-contrast composite materials are considered in all dimensions. The solution and its gradient, respectively, represent the electric potential and field. The novelty of this paper lies in finding exact solutions for the insulated and perfect conductivity problems with concentric balls. Our results show that there appears no electric field concentration for the insulated conductivity problem, while the electric field for the perfect conductivity problem exhibits sharp singularity with respect to the small distance between interfacial boundaries of the interior and exterior balls. This discrepancy reveals that concentric balls is the optimal structure of insulated composites, but not for superconducting composites.

Abstract Gut microbiota is closely related to human health and disease because, together with their metabolites, gut microbiota maintain normal intestinal peristalsis. The use of antibiotics or opioid anesthetics, or both, during surgical procedures can lead to dysbiosis and affect intestinal motility; however, the underlying mechanisms are not fully known. This review aims to discuss the effect of gut microbiota and their metabolites on postoperative intestinal motility, focusing on regulating the enteric nervous system, 5-hydroxytryptamine neurotransmitter, and aryl hydrocarbon receptor.

Hair/wool usually plays an important role in maintaining animal physiological activities, and the economic value of wool cannot be ignored. At present, people set higher demands on wool fineness. Hence, improving wool fineness is the concern of fine wool sheep breeding. Using RNA-Seq to screen the potential candidate genes that associate with wool fineness can provide theoretical references for fine-wool sheep breeding, and also provide us new ideas for further understand the molecular regulation mechanism of hair growth. In this study, we compared the expression pattern difference of genome-wide genes between the skin transcriptomes of Subo and Chinese Merinos. The results showed that, 16 candidate differentially expressed genes (DEGs) (Included: CACNA1S, GP5, LOC101102392, HSF5, SLITRK2, LOC101104661, CREB3L4, COL1A1, PTPRR, SFRP4, LOC443220, COL6A6, COL6A5, LAMA1, LOC114115342 and LOC101116863 genes) that may associate with wool fineness were screened, and these genes were located in signaling pathways that regulate hair follicle development, cycle or hair growth. It is worth noting that, among the 16 DEGs, COL1A1 gene has the highest expression level in Merino skins, and the fold change of LOC101116863 gene is the highest, and the structures of these two genes are both highly conserved in different species. In conclusion, we speculate that these two genes may play a key role in regulating wool fineness and respectively have similar and conserved functions in different species.

Abstract This paper considers the parameter estimation problem of a first-order threshold autoregressive conditional heteroscedasticity model by using the empirical likelihood method. We obtain the empirical likelihood ratio statistic based on the estimating equation of the least squares estimation and construct the confidence region for the model parameters. Simulation studies indicate that the empirical likelihood method outperforms the normal approximation-based method in terms of coverage probability.

Boron nitride nanosheet (BNNS) and graphene oxide (GO) as a single filler can effectively improve the thermal conductivity of the composites, and the synergistic mechanism of BNNS and GO was investigated in this paper. In this study, BNNS was first surface-functionalized and the multi-sized (50 nm, 200 nm, 500 nm) modified BNNS (A-BN) were attached to GO through non-covalent bonding interactions to form a cross-linked structure. Then, A-BN and GO were used as thermal fillers and support material adsorption eutectic phase change materials (PCMs) to prepare composite phase change material (CPCM). Characterization results show that small-size A-BN was more likely to form dense thermal networks with good compatibility and interface connectivity between PCMs, A-BN, and GO, ensuring that PCMs can be stored in the network without leaking. When the size of the BNNS was greater than 200 nm, the advantage of thermal conductivity obtained by A-BN was no longer obvious, and the phase change behavior of CPCM was inhibited. In general, the prepared CPCM has the ideal thermal response and thermal stability, which is very suitable for energy storage and thermal management applications.

Steel wheels, consisting of rims and spokes, are important load-bearing parts of vehicles, and the fatigue fractures’ life estimation accuracy directly determines the stability and safety when applied in the transportation industry. The most common form of failure is fatigue fracture. The strong elastic–plastic deformation during the rim roll-forming process generates a residual stress field in its surface layer, which changes the actual stress distribution in the rim when it is loaded and thus affects the fatigue life of the steel wheel. In this paper, ABAQUS software was used to establish a rim-rolling simulation model to obtain the residual stress field distribution after forming and compare it with the actual residual stress on the formed surface of the rim to verify the reliability of the model. On the basis of this model establishment, the service hazard areas and maximum stresses of steel wheels with or without superimposed residual stress fields were calculated separately, and their fatigue lives were predicted separately using the local stress-strain method. The simulation results show that the maximum stress of the rim before and after the superimposed residual stress occurs in the area of the bottom of the groove, which is consistent with the actual failure location. However, the maximum stress after superposition increased from 120.7 MPa to 332.9 MPa, and the corresponding calculated life decreased from 158,340,000 to 459,500 cycles, which is closer to the actual test results. The results of the study can provide a theoretical basis for the lightweight design and process improvement of automotive steel wheels.

Antibiotic-resistant ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) has become a serious threat to public health worldwide. Cationic α-helical antimicrobial peptides (CαAMPs) have attracted much attention as promising solutions in post-antibiotic era. However, strong hemolytic activity and in vivo inefficacy have hindered their pharmaceutical development. Here, we attempt to address these obstacles by investigating BmKn2 and BmKn2-7, two scorpion-derived CαAMPs with the same hydrophobic face and a distinct hydrophilic face. Through structural comparison, mutant design and functional analyses, we found that while keeping the hydrophobic face unchanged, increasing the number of alkaline residues (i.e., Lys + Arg residues) on the hydrophilic face of BmKn2 reduces the hemolytic activity and broadens the antimicrobial spectrum. Strikingly, when keeping the total number of alkaline residues constant, increasing the number of Lys residues on the hydrophilic face of BmKn2-7 significantly reduces the hemolytic activity but does not influence the antimicrobial activity. BmKn2-7K, a mutant of BmKn2-7 in which all of the Arg residues on the hydrophilic face were replaced with Lys, showed the lowest hemolytic activity and potent antimicrobial activity against antibiotic-resistant ESKAPE pathogens. Moreover, in vivo experiments indicate that BmKn2-7K displays potent antimicrobial efficacy against both the penicillin-resistant S. aureus and the carbapenem- and multidrug-resistant A. baumannii, and is non-toxic at the antimicrobial dosages. Taken together, our work highlights the significant functional disparity of Lys vs Arg in the scorpion-derived antimicrobial peptide BmKn2-7, and provides a promising lead molecule for drug development against ESKAPE pathogens.

Abstract In this paper, we consider the variable selection problem of the generalized random coefficient autoregressive model (GRCA). Instead of parametric likelihood, we use non-parametric empirical likelihood in the information theoretic approach. We propose an empirical likelihood-based Akaike information criterion (AIC) and a Bayesian information criterion (BIC).

This study investigates the origin and development of Tang blue-and-white porcelain. Test samples consist of excavated shards of blue-and-white porcelain, white porcelain, Tang tricolor pottery, and blue-on-white pottery from the Tang strata of the Baihe and the Huangye kiln sites. The chemical compositions, firing temperatures, and physical properties were studied scientifically, and multivariate statistical analysis was applied to analyze the compositional data. The results show that Tang blue-and-white porcelain developed from a mature manufacturing technology of white porcelain in the late Tang. Moreover, the type of cobalt pigment used is similar to that used for blue-on-white pottery. This study contributes to our understanding of the invention of Tang blue-and-white porcelain. Statement of significance In recent years, several shards of blue-and-white porcelain have been found in the late Tang strata of the Huangye and the Baihe kiln sites in Gongyi district of Henan Province (Henan Provincial Institute of Cultural Relics and Archaeology 2005,17; 2007; 2009,22). Notably, these are the only pieces of blue-and-white wares of the Tang dynasty that have been excavated at a kiln site. For the very first time, with data analysis of the chemical compositions and comparisons among pottery and porcelain throughout distinct time periods of the Tang Dynasty, this study explicates the invention of Tang blue-and-white porcelain from a scientific standpoint. Derived from Tang tricolor pottery, blue-on-white pottery and, especially, white porcelain production, raw materials and firing techniques lay the groundwork for the emergence of blue-and-white wares. The invention of Tang blue-and-white porcelain marks a crucial milestone in the developmental history of ancient Chinese ceramics.

Scorpion venoms are rich resources of antimicrobial peptides (AMPs). While the short-chain noncysteine-containing AMPs have attracted much attention as templates for drug development, the antimicrobial potential of long-chain noncysteine-containing AMPs has been largely overlooked. Here, by using the online HeliQuest server, we designed and analyzed a series of 14-residue fragments of Smp43, a 43-residue long-chain noncysteine-containing AMP identified from the venom of Scorpio maurus palmatus. We found that Smp43(1-14) shows high antimicrobial activity against both Gram-positive and Gram-negative bacteria and is nontoxic to mammalian cells at the antimicrobial dosage. Sequence alignments showed that the designed Smp43(1-14) displays a unique primary structure that is different from other natural short-chain noncysteine-containing AMPs from scorpions, such as Uy17, Uy192 and IsCT. Moreover, the peptide Smp43(1-14) caused concentration-dependent fluorescence increases in the bacteria for all of the tested dyes, propidium iodide, SYTOXTM Green and DiSC3-5, suggesting that the peptide may kill the bacteria through the formation of pore structures in the plasma membrane. Taken together, our work sheds light on a new avenue for the design of novel short-chain noncysteine-containing AMPs and provides a good peptide template with a unique sequence for the development of novel drugs for use against bacterial infectious diseases.

This paper presents a fault tolerant control (FTC) design for the actuator faults in a variable cycle engine (VCE). Ensured by the multiple variable geometries structure of VCE, the design is realized by distributing the control effort among the unfaulty actuators with the “functional redundancy” idea. The FTC design consists of two parts: the fault reconstruction part and the fault tolerant control part, which use a sliding mode observer (SMO) and a sliding mode control (SMC) scheme respectively. Considering the inaccuracy of the fault reconstruction result, the proposed design requires only inaccurate fault information. The stability of the closed-loop control system is proved and the existence condition for the proposed control law is analyzed. This work also reveals its relation to the sliding mode control allocation design and the adaptive SMC design. An application case is then studied for tolerating the loss of effectiveness fault of the nozzle area actuator. Results show that the FTC design is able to tolerate the fault and achieves the same control goal as in the fault-free situation. Finally, a hardware-in-the-loop test is carried out to verify the design in a real-time distributed control system, which demonstrates its use from the engineering perspective.

In this paper, a fuzzy logic based volume flow control method is proposed to precisely control the force of a pneumatic actuator in an electro-pneumatic system including four on-off valves. The volume flow feature, which is the relationship between the duty cycle of the pulse width modulation (PWM) period, pressure difference, and volume flow of an on-off valve, is based on the experimental data measured by a high-precision volume flow meter. Through experimental data analysis, the maximum and minimum duty cycles are acquired. A new volume flow control method is introduced for the pneumatic system. In this method, the raw measured data are innovatively processed by a segmented, polynomial fitting method, and a newly designed procedure for calculating the duty cycle is adopted. This procedure makes it possible to combine the original data with fuzzy logic control (FLC). Additionally, the method allows us to accurately control the minimum and maximum opening pulse width of the valve. Several experiments are performed based on the experimental data, instead of the traditional theoretical models. Only 0.141 N (1.41%) overshoot and 0.03 N (0.03%) steady-state error are observed in the step response experiment, and 0.123 N average error is found while tracking the sine wave reference.

As a kind of microscale physical evidence, soil can provide significant assistance to forensic science. In this study, soil samples that were collected from eighteen different regions of Shandong Province, China, were examined by scanning electron microscope-energy dispersive spectrometer (SEM-EDS). The homogeneities and diameters of the samples were evaluated by SEM which has been applied to observe objects at nanoscale. The soil from Jiaxiang, a city in Eastern Shandong Province, showed the maximal particle diameter and the sample from Liaocheng, another Eastern city in Shandong Province, showed the best homogeneity. The mass fraction and molar percentages of nine inorganic elements in all samples were analyzed by EDS. Oxygen and silicon showed the highest content in all of these samples. However, different samples exhibited their own characteristic elements, which can help to discriminate them from other samples. In this regard, SEM-EDS-based homogeneity and element analysis might be used as a fast and reliable technique for the soil criminological analysis in Shandong Province.

Voltage-gated sodium channel Nav1.5 has been linked to the cardiac cell excitability and a variety of arrhythmic syndromes including long QT, Brugada, and conduction abnormalities. Nav1.5 exhibits a slow inactivation, corresponding to a duration-dependent bi-exponential recovery, which is often associated with various arrhythmia syndromes. However, the gating mechanism of Nav1.5 and the physiological role of slow inactivation in cardiac cells remain elusive. Here a 12-state two-step inactivation Markov model was successfully developed to depict the gating kinetics of Nav1.5. This model can simulate the Nav1.5 channel in not only steady state processes, but also various transient processes. Compared with the simpler 8-state model, this 12-state model is well-behaved in simulating and explaining the processes of slow inactivation and slow recovery. This model provides a good framework for further studying the gating mechanism and physiological role of sodium channel in excitable cells.

A major application of a distributed WSN (wireless sensor network) is to monitor a specific area for detecting some events such as disasters and enemies. In order to achieve this objective, each sensor in the network is required to collect local observations which are probably corrupted by noise, make a local decision regarding the presence or absence of an event, and then send its local decision to a fusion center. After that, the fusion center makes the final decision depending on these local decisions and a decision fusion rule, so an efficient decision fusion rule is extremely critical. It is obvious that the decision-making capability of each node is different owing to the dissimilar signal noise ratios and some other factors, so it is easy to understand that a specific sensor contribution to the global decision should be constrained by this sensor decision-making capability, and, based on this idea, we establish a novel linear decision fusion model for WSNs. Moreover, the constrained particle swarm optimization (constrained PSO) algorithm is creatively employed to control the parameters of this model in this paper and we also apply the typical penalty function to solve the constrained PSO problem. The emulation results indicate that our design is capable of achieving very high accuracy.

Attentional processes play a crucial role in our ability to perceive and respond to relevant stimuli. The cerebellum, traditionally associated with motor control, has recently garnered attention as a potential contributor to attention modulation. This study aimed to investigate the effects of cerebellar intermittent theta-burst stimulation (iTBS) on attentional performance using three behavioral tasks: dot counting, target selection, and multi-tasking. Seventeen healthy participants underwent either real or sham iTBS stimulation over seven days, and their performance on the tasks was assessed. Results revealed that dot counting performance did not significantly differ between the real and sham stimulation groups. However, notable improvements were observed over time, suggesting a learning effect. In contrast, significant effects of iTBS stimulation were found in the target selection task, with participants receiving real stimulation demonstrating enhanced discrimination between targets and distractors. Additionally, the multitasking task exhibited significant main effects of both iTBS stimulation and time, indicating improved performance with stimulation and progressive enhancements over the study period. These findings highlight the potential of cerebellar iTBS stimulation to enhance attentional performance in specific task domains. The significant effects observed in the target selection and multi-tasking tasks provide promising evidence for the modulatory role of the cerebellum in attention. Further investigations into the underlying mechanisms and optimal stimulation parameters are warranted to refine our understanding of how cerebellar iTBS stimulation influences attentional processes. [ABSTRACT FROM AUTHOR]