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From the viewpoint of engineering application, the Mn-Cu based alloy plates are prepared to characterize both the mechanical properties as well as the damping capacity by employing the tensile test and dynamic mechanical analysis (DMA), respectively. The microstructure of MnCu alloy were determined by optical microscopy, while the tensile fracture morphology was observed by using a scanning electron microscopy. It is verified that the mechanical properties are similar to that of A3 steel while the vibration noise across the MnCu alloy plate cut about 5-15dB off during all the experiment frequency range from 20 to 300 Hz when the alloy backing plates are applied under a turbine electric generator. The internal friction characteristic of the alloy is disclosed to be dynamic hysteresis closely related to the vibration frequency, as well as to be static hysteresis that depending on strain amplitudes. With whatever vibration frequencies or strain amplitudes, the damping capacity (tan δ) of the alloy plate still shows satisfactory engineering application value higher than 0.02 at ambient temperature range around room temperature.

Data augmentation is crucial for enhancing the performance of text classification models when labelled training data are scarce. For natural language processing (NLP) tasks, large language models (LLMs) are able to generate high-quality augmented data. But a fundamental understanding of the reasons for their effectiveness remains limited. This paper presents a geometric and topological perspective on textual data augmentation using LLMs. We compare the augmentation data generated by GPT-J with those generated through cosine similarity from Word2Vec and GloVe embeddings. Topological data analysis reveals that GPT-J generated data maintains label coherence. Convex hull analysis of such data represented by their two principal components shows that they lie within the spatial boundaries of the original training data. Delaunay triangulation reveals that increasing the number of augmented data points that are connected within these boundaries correlates with improved classification accuracy. These findings provide insights into the superior performance of LLMs in data augmentation. A framework for predicting the usefulness of augmentation data based on geometric properties could be formed based on these techniques.

In this paper, to study unsteady hydraulic excitation characteristics of the impeller in stay vane volute pump, the radial force of that is investigated by vector analysis, time-frequency analysis and unsteady flow field analysis etc. Results show that the radial force distribution on the impeller has a linear relationship with the number of the blade under high flow conditions. Furthermore, the radial force has obvious directivity under low flow conditions. The radial force of the impeller is mainly distributed on the blade and the shroud. Interestingly, it is found that the radial force on the impeller is smaller than the radial force on the blade and shroud respectively, when there are cross peaks between the blade and the shroud. In addition, the results of the unsteady flow field analysis reveal that the radial force distribution of the impeller is unbalanced under low flow conditions. This result is due to the fact that jet wake forms at the impeller outlet and radial vortex leads to rotating stall in the flow channel. This work may provide some theoretical references for the optimal design and stable operation of the stay vane volute pump.

The hysteresis effect of volute pump with stay vanes in the hump zone can aggravate the vibration and jumping of the units, which seriously threatens the unit’s safety and stable operation. The formation mechanism of the hysteresis effect in hump zone is analyzed by carrying out unsteady numerical simulation of the volute pump with stay vanes at medium-low specific speed based on vortex dynamics theory. The results show that hysteresis effect occurs in volute pump, the fluid inertia force in FID is smaller than that in FDD, and the fluid viscous force in FID is larger than that in FDD. The hysteresis effect is not only related to the Karman vortex generated by the flow separation of vane and guide vane, but also closely related to the stall vortex generated in the volute. This work may provide a guide way for the optimal design and stable operation of the volute pump with stay vanes.

Bacterial lysates are known for having immunomodulatory properties and have been used mainly for the prevention and treatment of respiratory tract infections (RTIs). However, rigorous studies are needed to confirm the clinical efficacy of bacterial lysates with various bacterial antigen components, preparation methods, administration routes and course of treatment. OM-85, an oral standardized lysate prepared by alkaline lysis of 21 strains from 8 species of common respiratory tract pathogens, is indicated as immunotherapy for prevention of recurrent RTIs and acute infectious exacerbations of chronic bronchitis. OM-85 acts on multiple innate and adaptive immune targets and can restore type 1 helper T (Th1)/Th2 balance. Sporadic studies have shown advances in pharmacology and therapeutics of OM-85, and thus an update review is necessary. Literature was retrieved by searching PubMed, Web of science, Embase, CNKI, and Full Text Database of Chinese Medical Journals. New roles of OM-85 were discovered in prevention and treatment of lung cancer, pulmonary tuberculosis, SARS-CoV-2 infection, allergic rhinitis, pulmonary fibrosis, atopic dermatitis, and nephrotic syndrome. Pharmacoeconomic values of OM-85 were demonstrated in prophylaxis and treatment of RTIs, chronic obstructive pulmonary disease, asthma, chronic bronchitis, rhinosinusitis and allergic rhinitis. Two consecutive courses of OM-85 (6 or 12 months apart) could prevent recurrent RTIs in children. Maternal OM-85 treatment could offer benefits for offspring. Product-specific response was observed. The efficacy of OM-85 may be associated with patient's characteristics (eg, severity of the disease, age, immune response pattern, malignancy risk stratification). OM-85 can improve effectiveness of standard care for some primary diseases, and carry significant pharmacoeconomic implications. The benefits shown by OM-85 in vitro and in vivo, when extrapolated to humans, are exciting but also require caution. Individualized treatment may need to be considered. It is necessary to compare the efficacy and safety of various bacterial lysate preparations.

An intense electron-beam accelerator, which consists of a primary storage capacitor system, a magnetic core Tesla transformer, Blumlein pulse forming line of water dielectric, and a field-emission diode, are constructed and described. The experimental results show that the output voltage of transformer is more than 740 kV, the rise time is about 5 µs, the diode voltage is about 596 kV, electron beam current is about 60 kA, the duration is about 100 ns, and the power is 36 GW when charging voltage is 40 kV. It was suitable to drive magnetically insulated transmission line oscillator. And it can be also used in materials surface modification. This accelerator is very compact and works stably and reliably.

A high voltage pulse Tesla transformer with a coupling coefficient of 0.75 was designed and experimentally investigated. The transformer was employed to charge a spiral water pulse forming line (PFL) in a high current electron beam accelerator, and was featured by its compactness, stability, and reliability. When the primary input voltage is 55 kV, the transformer can charge the PFL to 720 kV with an energy conversion efficiency of 36%. The formulas for calculating the primary and secondary inductances of the transformer were deduced, with which the main parameters of the transformer were calculated theoretically. The distributions for electrical and magnetic fields in the transformer were obtained by the simulations of calculation. In addition, the process of an accelerator of the transformer charging a spiral PFL was simulated through the Pspice software to get the waveform of charging voltage, the diode voltage, and diode current of accelerator. The theoretical and simulated results agree with the experimental results.

The objective of this study was to investigate the effects of immunological challenge on the skeletal muscle fiber type conversion of piglets. Sixteen Large White weaned barrows (28 ± 3 d, 8.22 ± 0.89 kg BW) were allotted by weight and litter to 2 groups: the control group and the lipopolysaccharide (LPS) group. Saline (control) or LPS was injected intravenously via a jugular catheter on d 1, 3, 5, 7, 9, 11, 13, and 15 at an initial dosage of 80 μg/kg BW, which was increased by 30% at each subsequent injection. Blood samples were collected via the jugular catheter 3 h after the LPS challenge on d -1, 1, 5, 9, and 13. Muscle tissue samples were collected from the LM after exsanguination on d 15. The LPS challenge increased the plasma IL-6, tumor necrosis factor-α (TNF-α), cortisol, IL-1β, and haptoglobin concentrations on d 1 and 5 ( < 0.01) and increased the plasma IL-6 ( < 0.05), TNF-α ( < 0.05), and haptoglobin ( < 0.01) levels on d 9. Compared with that of the control group, the ADG of the LPS group decreased by 40.00% ( < 0.01), 29.52% ( < 0.05), and 19.30% ( < 0.05), and the ADFI decreased by 25.09% ( < 0.01), 23.15% ( < 0.05), and 19.47% ( < 0.05) during d 1 to 4, d 5 to 8, and d 9 to 15, respectively. In the LM of LPS-challenged piglets, myosin heavy chain 1 (MyHC1) mRNA and protein expression tended to be reduced ( = 0.08, 0.09), whereas mRNA, mRNA, and MyHC2 protein expression increased ( < 0.05). The LPS challenge reduced succinic dehydrogenase (SDH) activity ( < 0.05) and increased lactate dehydrogenase (LDH) activity ( < 0.05) in the LM of piglets. Compared with those in the control group, transcriptional peroxisome proliferator-activated receptor coactivator-α () mRNA ( < 0.05), calcineurin (CaN) mRNA, and protein expression were reduced ( < 0.05), and PGC-α protein expression tended to be reduced ( = 0.08) in the LM of LPS-challenged piglets. These results show that immunological challenge induced by LPS resulted in a shift from type I to type II fibers in the LM of piglets, which may be mediated by the downregulation of the CaN/PGC-α signaling pathway.

Purpose: Nightmare is common and is also independently implicated in suicide risk among the adolescent population. Adolescents with major depressive disorder (MDD) are at an increased risk of suicide. Therefore, comorbid nightmares may amplify suicide risk among this clinical population. This study aimed to explore the effects of nightmares on suicide risk among adolescents with MDD. Patients and Methods: Subjects were 499 outpatients aged 12-18 in four large psychiatric hospitals clinic of China, from January 1 to October 31, 2021. Simultaneously, we matched 499 healthy controls according to gender and age. All participants underwent affective state (depressive and anxiety symptoms) and sleep variable (nightmare frequency/distress, insomnia symptoms, and daytime sleepiness) evaluation as well as MDD diagnoses and determination of suicide risk by a fully structured diagnostic clinical interview. Results: Adolescents with MDD reported a higher incidence of frequent nightmares (at least one night per week) and level of nightmare distress than healthy controls (22.0% vs 6.1%; 28.85 [+ or -] 11.92 vs 17.30 [+ or -] 5.61). Over half of the patients with suicide risk (51.6%) experienced frequent nightmares compared with approximately one-third of those at a risk for suicide (30.7%). Patients with suicide risk scored scientifically higher on sleep variables, depressive and anxiety symptoms than those without the risk. Further logistic regression analysis indicated that female gender, junior grade, recurrent depressive episode, severe nightmare distress and severe depressive symptoms were independently and significantly associated with suicide risk. Conclusion: Our study provided evidence that adolescents with MDD experienced a higher prevalence of frequent nightmares and suffered more nightmare distress. Nightmare distress is an independent risk factor for suicide risk. Keywords: major depressive disorder, sleep problems, nightmare, suicide risk, adolescent

The use of limiters may impact both accuracy and resolution of a solution. And the accuracy and resolution are highly dependent on the amount of numerical dissipation in a scheme, so the ability of limiters to control numerical dissipation should be improved. In this view, based on the examination of several classical limiters to control dissipation, a class of general piecewise-linear flux limiters (termed GPL limiters) are presented in this paper for Multi-step time-space-separated unsteady schemes. The GPL limiters can satisfy the second-order TVD criterion and contain some existing limiters such as Superbee and Minmod. Using the decrement of discrete total entropy to represent the amount of numerical dissipation, an entropy dissipation function of GPL limiters is defined with three parameter variables. By proving the monotonicity of this function, a new GPL type limiter (named MDF individually), which can minimize the numerical dissipation and improve the calculation accuracy, is proposed. A high resolution entropy-consistent scheme is obtained by MDF limiter, which will be proved to satisfy entropy stability and entropy consistency. Computational results of this scheme for several 1-D and 2-D Euler test cases are presented, demonstrating the accuracy, monotonicity and robustness of MDF limiter.