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Background: Gastrointestinal stromal tumor (GIST) is a common tumor that originates from the alimentary system mesenchyme. Compared to typical gastrointestinal carcinomas, GISTs exhibit unique malignant behaviors. Bioinformatic tools and subsequent experiments were applied to investigate novel targets involved in GIST progression and imatinib resistance. Methods: Differences in gene expression profiles between advanced and nonadvanced GISTs were comprehensively analyzed based on the Gene Expression Omnibus (GEO) dataset GSE136755. A protein–protein interaction (PPI) network was constructed to identify the potential target gene. Gene set enrichment analysis (GSEA) was used to elucidate relevant biological events related to the target gene based on the GSE47911 dataset. Subsequently, immunohistochemistry and Kaplan–Meier analysis were performed to validate the prognostic value of the target gene in GISTs. Overexpression of the target gene was conducted to analyze its function in the proliferation, apoptosis, and imatinib resistance of GIST/T1 cells. Results: In the current study, a total of 606 differentially expressed genes (DEGs) were screened based on the GSE136755 dataset, and the upregulated DEGs in advanced GISTs were mainly involved in cell division through functional annotations. The intersecting hub gene, Aurora kinase A (AURKA), was identified by degree and bottleneck algorithms. GSEA revealed that AURKA was involved in cell cycle-related biological processes. Analysis of the Oncomine and GEPIA databases revealed a pattern of elevated AURKA expression in most human malignances. Clinical assays demonstrated that AURKA could be an independent prognostic factor for GISTs. Additionally, overexpression of AURKA was experimentally demonstrated to promote cell proliferation, inhibit cell apoptosis, and enhance imatinib resistance in GIST/T1 cells. Conclusions: These findings indicated that overexpression of AURKA promoted GIST progression and enhanced imatinib resistance, implying that AURKA is a potential therapeutic target for GISTs. [ABSTRACT FROM AUTHOR]

Background: The current coronavirus disease 2019 (COVID-19) is a public health emergency. In this study, we aimed to evaluate the risk factors for mortality in severe and critical COVID-19 patients.Methods: We performed a retrospective study of patients diagnosed with severe and critical COVID-19 from four hospitals in Wuhan, China, by evaluating the clinical characteristics and laboratory results, and using Cox proportional hazards model to assess the risk factors involved in disease progression.Results: In total, 446 patients with COVID-19 were enrolled. The study indicated a high mortality rate (20.2%) in severe and critical COVID-19 patients. At the time of admission, all patients required oxygen therapy, and 52 (12%) required invasive mechanical ventilation, of which 50 (96%) died. The univariate Cox proportional hazards model showed a white blood cell count of more than 10 × 109/L (HR 3.993,95%CI 2.469 to 6.459) that correlated with an increased mortality rate. The multivariable Cox proportional hazards model demonstrated that older age (HR 1.066, 95% CI 1.043 to 1.089) and higher white blood cell count (HR 1.135, 95% CI 1.080 to 1.192) were independent risk factors for determining COVID-19 associated mortality.Conclusions: COVID-19 is associated with a significant risk of morbidity and mortality in the population. Older age and higher white blood cell count were found to be independent risk factors for mortality. [ABSTRACT FROM AUTHOR]

Halide superionic conductors (SICs) are drawing significant research attention for their potential applications in all‐solid‐state batteries. A key challenge in developing such SICs is to explore and design halide structural frameworks that enable rapid ion movement. In this work, we show that the close‐packed anion frameworks shared by traditional halide ionic conductors face intrinsic limitations in fast ion conduction, regardless of structural regulation. Beyond the close‐packed anion frameworks, we identify that the non‐close‐packed anion frameworks have great potential to achieve superionic conductivity. Notably, we unravel that the non‐close‐packed UCl3‐type framework exhibit superionic conductivity for a diverse range of carrier ions, including Li+, Na+, K+, and Ag+, which are validated through both ab initio molecular dynamics simulations and experimental measurements. We elucidate that the remarkable ionic conductivity observed in the UCl3‐type framework structure stems from its significantly more distorted site and larger diffusion channel than its close‐packed counterparts. By employing the non‐close‐packed anion framework as the key feature for high‐throughput computational screening, we also identify LiGaCl3 as a promising candidate for halide SICs. These discoveries provide crucial insights for the exploration and design of novel halide SICs. [ABSTRACT FROM AUTHOR]

Halide superionic conductors (SICs) are drawing significant research attention for their potential applications in all‐solid‐state batteries. A key challenge in developing such SICs is to explore and design halide structural frameworks that enable rapid ion movement. In this work, we show that the close‐packed anion frameworks shared by traditional halide ionic conductors face intrinsic limitations in fast ion conduction, regardless of structural regulation. Beyond the close‐packed anion frameworks, we identify that the non‐close‐packed anion frameworks have great potential to achieve superionic conductivity. Notably, we unravel that the non‐close‐packed UCl3‐type framework exhibit superionic conductivity for a diverse range of carrier ions, including Li+, Na+, K+, and Ag+, which are validated through both ab initio molecular dynamics simulations and experimental measurements. We elucidate that the remarkable ionic conductivity observed in the UCl3‐type framework structure stems from its significantly more distorted site and larger diffusion channel than its close‐packed counterparts. By employing the non‐close‐packed anion framework as the key feature for high‐throughput computational screening, we also identify LiGaCl3 as a promising candidate for halide SICs. These discoveries provide crucial insights for the exploration and design of novel halide SICs. [ABSTRACT FROM AUTHOR]

We have designed and synthesized a novel copillar[5]arene-based chemosensor, which employ 8-hydroxyquinoline group as a binding site and signal group. By a novel cyanide-induced self-assemble mechanism, the pillar[5]arene-based chemosensor shown high sensitivity and selectivity for cyanide in aqueous media. When cyanide was added to the solution of the chemosensor, a strong chartreuse fluorescence appeared. The detection limit of the fluorescent spectrum is 1.08 × 10 −8 mol L −1 for cyanide. Moreover, test strips based on the sensor were fabricated, the chemosensor is a good cyanide test kits. In addition, we made life applications of cyanide detected, the chemosensor is also could detect cyanide in aqueous extracts from sprouting potatoes. It is worth mentioning that cyanide-induced self-assemble mechanism is a novel strategy for the design of pillararene based chemosensor. Moreover, to the best of our knowledge, it's the first example of pillararene based cyanide chemosensors. [ABSTRACT FROM AUTHOR]

This paper studies a two-stage model for the optimization of charging scheduling and charging station construction planning based on the spatial-temporal complementarity of charging demand, in order to improve the overall satisfaction of the whole society. In the first stage, starting from the probability of trip starting point and other characteristics, the simulation of load demand is realized based on Monte Carlo simulation, and the charging plan regulation method is created combined with the principle of Dijkstra algorithm. In the second stage, a solution path based on discrete binary particle swarm optimization is proposed. The experimental results of 14 scenarios show that no matter disorderly charging or orderly charging, the annual social comprehensive cost of the scenario with five charging stations is the lowest. Compared with disordered charging, the total construction capacity of charging station is reduced by 51.61%, and the annual social comprehensive cost is reduced by 29.35%. Therefore, this study provides a framework for the optimal configuration of charging stations, which is applicable when considering or not considering demand response, and provides a solution for the future green development planning of urban charging infrastructure. [Display omitted] • The two-stage optimization framework can achieve multiple objectives. • Monte Carlo method can make full use of spatiotemporal complementarity. • DBPSO has good results in solving discrete space problems. • The comparison of 14 scenarios proves the value of the research. [ABSTRACT FROM AUTHOR]

Abstract: The manganese peroxidase (MnP) was isolated and purified from Schizophyllum sp. F17 on pinewood solid-state cultures. Fractionation of MnP was performed by Sephadex G-75 gel filtration chromatography followed by DEAE-cellulose anion exchange chromatography. This purification attained 3.8% activity yield with a purification factor of 9.2. According to data on sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE), the molecular weight of the enzyme was 48.7kDa. The enzyme was a glycoprotein with 18% of its weight in carbohydrates. The optimum pH and temperature of purified MnP for oxidation of DMP were 6.8 and 35°C, respectively. This enzyme was stable in the pH range 4.0–7.0, at 25°C for 1h incubation period. The effects of possible inhibitors and activators of enzyme activity were investigated. The K m values of MnP for Mn2+, H2O2, guaiacol, ABTS and DMP were 35.2, 6.7, 13.1, 47.8 and 122.9μM at pH 4.5, respectively. The azo dyes such as Congo Red, Orange G and Orange IV were efficiently decolorized using the MnP purified. [Copyright &y& Elsevier]

This paper studies the capacity of electric vehicle charging station (EVCS) and energy storage, and the optimization problem and model of electric vehicle (EV) charging scheduling plan. Based on the alternative energy storage effect of EVs, it is committed to improve the renewable energy consumption capacity in micro-grid, reduce the EVCS and energy storage capacity, and improve the comprehensive benefits of micro-grid investors. In this paper, considering the factors that affect the efficiency and system security, the determination model of EVCS and energy storage capacity is established, and the traditional simulated annealing algorithm (SA) is improved to create a disturbance mechanism for the optimization of charging scheduling plan, and the joint optimization is realized. The empirical analysis results show that the EVCS and energy storage capacity are reduced by about 50%, and the benefit of micro-grid investors is increased by about 7%. Therefore, this study can provide solutions for the planning of micro-grid with distributed energy, conventional users, energy storage and adjustable load, maximize renewable energy consumption and improve the satisfaction of all participants. Keywords : Electric vehicle charging station; Alternative energy storage effect; Net annual value; Improved simulated annealing algorithm; Joint capacity optimization. • The alternative energy storage effect of EVs is considered. • Capacity and scheduling strategy optimization are realized together. • A disturbance mechanism for 24-h-a-day vector is created. • The capacity is reduced and the benefit is improved. [ABSTRACT FROM AUTHOR]

In sound absorbers, acoustic resistance and reactance are usually coupled together and affect each other, which brings difficulties to impedance matching. An impedance decoupling method is proposed to make acoustic resistance and acoustic reactance vary independently. For the same thickness and perforation rate, acoustic reactance of the perforated panel with tube bundles (PPTBs) varies with the diameter of the tube, but acoustic resistance remains constant. Theoretical and simulated results show that a PPTB absorptive unit can exhibit resonance modes with varying damping states through impedance decoupling. It is found that through well-modulation, the PPTB unit in a slightly over-damped state cannot only maintain high sound absorption coefficients, but also expand the absorption peak bandwidth. Utilizing the mechanism of impedance decoupling, a broadband absorber is designed and evaluated by comprising the PPTB and microperforated panel (MPP). Measurement results indicate that it possesses an average absorption coefficient of 85% spanning more than a 3-octave bandwidth from 160 Hz to 1400 Hz with a deep sub-wavelength thickness. The impedance decoupling method helps to implement sound absorbers with highly efficient low-frequency broadband absorption. [ABSTRACT FROM AUTHOR]

It has previously been reported that cardamonin is able to regulate glycometabolism and vasodilation whilst also exhibiting anti‑inflammatory and antitumor properties. The antitumor effect of cardamonin is multifaceted, and so it is necessary to investigate the antitumor mechanisms of cardamonin at the molecular level. Cardamonin alters chemotherapy‑resistant colon cancer cell growth; however, the underlying mechanism is unknown. The present study was conducted to investigate the effect of cardamonin on chemotherapy‑resistant colon cancer cells and the possible mechanisms of action. Cardamonin significantly suppressed the growth of chemotherapy‑resistant colon cancer cells, induced apoptosis and promoted caspase‑3/9 activity and Bax protein expression in 5‑fluorouracil (5‑FU)‑resistant HCT‑116 cells. Cardamonin significantly suppressed c‑MYC, octamer‑binding transcription factor 4, cyclin E, testes‑specific protease 50 and nuclear factor‑κB protein expression in 5‑FU‑resistant HCT‑116 cells. The findings of the present study demonstrate that cardamonin suppresses chemotherapy‑colon cancer cell via the NF‑κB pathway in vitro. [ABSTRACT FROM AUTHOR]

• A design method is developed to expand the sound absorption bandwidth by utilizing coiled cavity combined with the perforated panel with tube bundles (PPTB). • The PPTB can maintain effective sound absorption at low frequencies, and the coiled-up cavity is utilized to stimulate high-order resonance modes. • The multi-order resonance mechanism is distinctly revealed by the sound pressure distribution and energy dissipation inside the proposed structure. • Though coupled-mode theory, the optimally geometrical parameters are determined to maintain the high muti-order absorption peaks and provide the wider single-order absorption peak. • A broadband absorbing metamaterial obtains an average absorption coefficient above 0.93 within 300–3600 Hz by coupling multi-order resonance peaks. Acoustic absorbers based on single-order resonant mode of the resonators have been extensively investigated for low-frequency broadband absorption. However, they are usually limited to a certain range of working frequency bands and often do not work effectively in the high frequency range. Here, we present an acoustic metamaterial, perforated panel with tube bundles (PPTB) combined with coiled-up cavity, which effectively expands the operating bandwidth from low to high frequencies by utilizing the multi-order resonances. The PPTB ensures the efficient low-frequency absorption effect though the adjustment of tube diameter and length. The coiled-up prolongs the propagation path of sound waves, thereby facilitating the excitation of higher-order resonance modes at high frequencies. The multi-order resonances mechanism of the metamaterial is revealed thoroughly by theoretical calculations and finite element simulations. The results show that at the first-order peak, the energy dissipation mainly occurs in the tubes, while for the high-order peaks, the energy dissipation of coiled-up cavity gradually increases. Moreover, this work introduces the coupled-mode theory to determine the reasonably structural parameters, which enables to achieve the desired leakage and loss factors simultaneously, maintaining the higher muti-order absorption peaks in a wide frequency band and providing the wider single-order absorption peak in high frequency range. Utilizing multi-order resonances, a broadband metamaterial supporting an average absorption coefficient above 0.93 within 300–3600 Hz and eliminating the tangible absorption dips is obtained, which is mutually verified by theory, simulation and experimentation. Owing to its lightweight, less-complicated structure, terrific acoustic and mechanical performance, this kind of metamaterial may have a broad application prospect in noise control engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigates the sound insulation capabilities of two electromagnetic induction membranes controlled by shunt circuits in the duct sound field. The real and imaginary parts of the diaphragm acoustic impedance can be precisely decoupled and regulated through the operational amplifiers and adjustable resistors in the shunt circuits. The parameter indicators Γ H (B 2 l 2 / (2 M m R δ 2)) and Γ L (B 2 l 2 C m / (2 R δ 2)) are also presented to evaluate the adjustable performance of the diaphragm and the side sound insulation performance. Finally, the performance of a duct sound insulation system composed of two electromagnetic units was demonstrated through theory and experiments. The maximum sound insulation level was 17.4 dB with a pair of units. [ABSTRACT FROM AUTHOR]

• An ultra-broadband composite sound absorber composed of perforated panel resonators with tube bundles (PPTB) and porous sound absorbing materials (PSAM) is designed and investigate. • The low-frequency resonance absorption of PPTB, the high-frequency energy dissipation of PSAM, and as well as the interaction of PPTB and PSAM constitute sound absorption mechanism of this composite structure. • The PPTB units in over-damped states arranged in parallel with the porous materials can expand the absorption bandwidth and enhance the absorption efficiency. • The designed PPTBs-PSAM with thickness of 75 mm can realize ultra-broadband absorption with a high absorption spectrum (>0.9) in the frequency range of more than 400 Hz. An ultra-broadband composite sound absorber composed of perforated panel resonators with tube bundles (PPTB) and porous sound absorbing materials (PSAM) is designed. The PPTB is established by utilizing multiple resonators with different resonance frequencies to obtain continuous low-frequency broadband absorption. By introducing PSAM in a proper manner around PPTB, the surface impedance of the structure is matched with air over a broader frequency range. As a result, the composite absorber designed with PPTB and PSAM achieves ultra-broadband sound absorption performance through the coupling effects of low-frequency resonance absorption by PPTB and high-frequency energy dissipation by PSAM. The acoustic-electrical analogy model and the finite-element method are applied to analyze the sound absorption performance. The results show that the composite structure has an average absorption coefficient of 0.93 in the ultra-broadband frequency range of 400 Hz–10 kHz. Moreover, the influence of structural parameters on the sound absorption performance is discussed, and the coupling sound absorption efficiency of PPTB unit under different damping states is compared. The impedance tube measurements validate that the ultra-broadband composite structure exhibits remarkable sound absorption properties within the frequency range of 400 Hz–1600 Hz. In comparison with porous materials of the same thickness, this composite sound absorber significantly enhances its low-frequency absorption performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A parallel-coupled hierarchical structure is proposed to obtain two independent frequency bands of sound absorption. • The absorber exhibits low-frequency broadbandabsorption performance approaching causality-governed minimal thickness. • The structure exhibits an exceptional ability to modulate impedance and a superior capacity for tuning absorption peaks. • The modular combination design overcomes the shortcomings of only working effectively in a fixed frequency range. Conventional series-coupled or parallel-coupled sound absorbers can only work effectively in a fixed frequency range, of which the absorption spectra can not be allowed to divide. Here, a parallel-coupled hierarchical structure with two relatively independent frequency bands of sound absorption is proposed. The hierarchical structure is composed of two type subunits of embedding neck Helmholtz resonator (ENHR) and segmented neck Helmholtz resonator (SNHR). Sound energy in the high-frequency region is dissipated in the first layer by the multiple local resonances coupling of ENHRs. The second layer effectively captures and absorbs low-frequency energy through the coupling of multiple SNHRs with varying parameters. The comprehensive discussion on the effects of acoustic impedance and structural parameters highlights the superior capability of this structure in impedance modulation. To demonstrate its broadband absorption performance, a hierarchical structure consisting of 20 subunits is employed. Finally, a above 90% broadband quasi-perfect absorption over a frequency range from 450 Hz to 1750 Hz is achieved under a thickness of 48 mm. Furthermore, a dual-band modular design concept for frequency-selective absorption is presented based on the tunability and independence of the two absorption bands. Therefore, the proposed hierarchical structure achieves reconfigurability by replacing either the first or second layer, thereby breaking away from traditional parallel design methods and providing a practical approach to controlling noise sources whose spectral characteristics change with operating conditions. [ABSTRACT FROM AUTHOR]

Hepatoblastoma (HB) and hepatocellular carcinoma (HCC) both exhibit notable cancer stem cell (CSC) features. Moreover, the development of both diseases is closely associated with the presence of CSCs. We investigated the role of brain-expressed X-linked protein 1 (BEX1) in regulating the CSC properties of HB and a subtype of HCC with high CSC features (CSC-HCC). Stemness scores were analyzed in 5 murine HCC models. A subpopulation of BEX1-positive cells and BEX1-negative cells were sorted from HCC cell lines, and subjected to transcriptome analysis. The expression and function of BEX1 was examined via western blotting, sphere formation assays, and xenograft tumor models. We identified BEX1 as a novel CSC marker that was required for the self-renewal of liver CSCs. Furthermore, zebularine, a potent DNMT1 inhibitor, can induce the reactivation of BEX1 by removing epigenetic inhibition. Notably, BEX1 was highly expressed in patients with HB and CSC-HCC, but not in patients with non-CSC HCC. Moreover, DNMT1-mediated methylation of the BEX1 promoter resulted in differential BEX1 expression patterns in patients with HB, CSC-HCC, and non-CSC-HCC. Mechanistically, BEX1 interacted with RUNX3 to block its inhibition of β-catenin transcription, which led to the activation of Wnt/β-catenin signaling, and stemness maintenance in both HB and CSC-HCC. In contrast, downregulated BEX1 expression released RUNX3 and inhibited the activation of Wnt/β-catenin signaling in non-CSC-HCC. BEX1, under the regulation of DNMT1, is necessary for the self-renewal and maintenance of liver CSCs through activation of Wnt/β-catenin signaling, rendering BEX1 a potentially valuable therapeutic target in both HB and CSC-HCC. Cancer stem cells (CSCs) contribute to a high rate of cancer recurrence, as well as resistance to conventional therapies. However, the regulatory mechanisms underlying their self-renewal remains elusive. Herein, we have reported that BEX1 plays a key role in regulating CSC properties in different types of liver cancer. Targeting BEX1-mediated Wnt/β-catenin signaling may help to address the high rate of recurrence, and heterogeneity of liver cancer. [Display omitted] • BEX1 is an oncofetal protein and a novel stem cell marker for hepatoblastoma and hepatocellular carcinoma. • BEX1 levels are regulated by expression of DNA methyltransferase 1. • BEX1 inhibition can sensitize liver cancer cells to sorafenib treatment. • BEX1 enhances stemness through beta-catenin signaling. • BEX1 upregulates beta-catenin by blocking RUNX3, a transcription factor that downregulates beta-catenin levels. [ABSTRACT FROM AUTHOR]

Numerous studies have revealed that the gut microbiota serves an important role in the pathogenesis of colorectal cancer (CRC). The present study aimed to investigate the populations present in the gut microbiota in patients with CRC of different stages and at different sites. Fecal samples were obtained from 67 CRC patients and 30 healthy controls, which were analyzed by sequencing the V3-V4 region of the 16S rRNA gene. Increased diversity of the fecal gut microbiota in patients with CRC was reported compared with the healthy controls. In the present study, at the genus level, the relative abundances of Prevotella, Collinsella and Peptostreptococcus in the gut microbiota of CRC patients were substantially increased compared with healthy controls, while the relative abundance of Escherichia-Shigella was significantly lower. In addition, differences in the fecal gut microbiota were also compared between patients with stage I–IV CRC and healthy controls. The results revealed that the abundances of the genera Peptostreptococcus, Collinsella and Ruminococcus were significantly increased in patients with CRC stage I compared with the healthy controls, while Alistipes was enriched in patients with stage III CRC compared with patients with stage IV. Furthermore, the present study reported that the genera Veillonella and Coprobacter were more abundant in the proximal segments than in the distal segments of the colon. In conclusion, despite the low number of samples employed in the present study, a signature of genera indicating dysbiosis of the gut microbiota of patients with stage I–IV CRC patients was proposed, which may provide insight into the mechanisms underlying the progression of CRC. These findings are also valuable for developing novel fecal diagnostic methods and therapeutic strategies for the treatment of CRC. [ABSTRACT FROM AUTHOR]

• A novel predication method of far-field sound radiation is proposed. • Pseudoinverse transfer function is deduced and investigated using operational data. • An independent operation recognition model is presented for complex system. • Experimental work is conducted to validate the effectiveness of proposed method. Prediction of the far-field sound radiation has been a major concern in many applications, in particular for complex vibro-acoustic systems due to practical issues of the complicated structure, boundary condition and sensor deployment. In this paper, a novel predication method based on the pseudoinverse transfer function in combination with operational recognition is proposed for far-field sound radiation of complex systems. In the method, the pseudoinverse transfer function between the near field and far field is first deduced by using the operational data. Besides, the independent calculation method of the pseudoinverse transfer functions is investigated and performed to reduce an error in the prediction caused by interferences among the operations. A hybrid model with the principal component analysis and k-means is subsequently presented in the independent operation recognition of the complex system. Experimental work is conducted on a double-layer cylindrical shell in an anechoic pool to validate the proposed method. [ABSTRACT FROM AUTHOR]

One major challenge currently facing pipeline networks across the world is the improvement of leak detection technologies in urban environments. There is an imperative to locate accurately leaks in buried water pipes to avoid serious environmental, social and economic consequences. Much attention has been paid to time delay estimation (TDE) in determining the position of a leak by utilising cross-correlation, which has been proven to be effective with varying degrees of success over the past half century. Previous research in published literature has demonstrated the effectiveness of the pre-whitening process for accentuating the peak in the cross-correlation associated with the time delay. This paper is concerned with the implementation of the differentiation process for TDE, with particular focus on the problem of determining a leak in pipelines by means of pipe pressure measurements. Rather than the pre-whitening operation, the proposed cross-correlation via the differentiation process, termed here DIF, changes the characteristics of the pipe system so that the pipe effectively acts as a band-pass filter. This method has the potential to eliminate some ambiguity caused by the interference at low frequencies and to allow more high frequency information to pass. Given an appropriate differentiation order, a more pronounced and reliable peak is obtained in the cross-correlation result. The use of differentiation process may provide a viable cross-correlation method suited to water leak detection. Its performance in relation to leak detection is further compared to the basic cross-correlation and pre-whitening methods for TDE in detecting a leak from actual PVC water pipes. Experimental results are presented to show an additional property of the DIF compensating for the resonance effects that may exist in cross-spectral density measurements, and hence better performance for TDE. [ABSTRACT FROM AUTHOR]

A fully elastic cavity, also terms as a box-structural-acoustic system, comprises six flexible panels whose displacements are coupled with the sound pressure inside the cavity. The fully elastic cavity (FEC) is common in practice, such as converting capacitor shells, sound boxes, and computers. In this study, the vibroacoustic properties of the FEC are modeled theoretically and then simulated using a finite-element modeling (FEM) software. Three types of objective functions are proposed to describe the vibroacoustic properties of the FEC and to study the control strategies of the FEC controlled by piezoelectric shunt oscillators (PSOs). Finally, the effects of the PSOs controlling the FEC at 130 Hz and in the low-frequency band of 50 Hz ∼ 200 Hz are investigated. The theoretical and FEM results both show that PSOs can attenuate the radiated sound power of the controlled panels by 5 ∼ 30 dB while decreasing the sound radiation of other panels and the internal sound potential energy by 3 ∼ 25 dB. The basic control strategies of the FEC controlled by PSOs are also determined. [ABSTRACT FROM AUTHOR]

Dimethoxycurcumin ( DMC) is a lipophilic analog of curcumin, an effective treatment for colon cancer, which has greater chemical and metabolic stability. Chemotherapy treatments, such as 5-fluorouracil (5-Fu), play a key role in the current management of colon cancer. In this study, we investigated the antitumor efficacy of DMC in combination with 5-Fu in SW480 and SW620 colon cancer cells. CCK-8 assay was used to evaluate the inhibitory effect of DMC and 5-Fu on cancer cells proliferation, and the combination index was calculated. The influence of DMC and 5-Fu on cell cycle, apoptosis, reactive oxygen species ( ROS) production, and mitochondrial membrane potential in SW480 and SW620 cells was determined using flow cytometry, and the related signaling pathways were detected by western blot. Transmission electron microscopy was used to observe endoplasmic reticulum expansion. DMC- and/or 5-Fu-induced apoptosis, stimulated G0/G1 phase arrest, increased ROS levels, decreased mitochondrial membrane potential, and enhanced endoplasmic reticulum expansion. The induction of apoptosis is involved in the increasing of Bax and cytochrome c and decreasing of Bcl2 expressions. Increased production of ROS was accompanied by upregulation of CHOP and Noxa. Combination therapy of DMC and 5-Fu had increased efficacy on the above pathways compared with either drug alone. Based on the calculated IC50, combination treatment with DMC and 5-Fu had an additive antitumor effect in both cell lines. Combined treatment with DMC and 5-Fu led to an additive antitumor effect in colon cancer cells that was related to apoptosis induction, G0/G1 phase arrest, increased ROS production, decreased mitochondrial membrane potential, and enhanced endoplasmic reticulum expansion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dispersion relation in honeycomb structure is calculated more accurately by taking advantage of the space periodicity of the core. • A flexural wave band gap is discovered and verified in the intact area of the honeycomb structure. • A new nondestructive method for detecting the debonding defect is proposed by using the band gap feature and the corresponding detection device is developed. Honeycomb structure is increasingly applied in various fields due to its high strength-to-weight ratios. However, due to the complex wave field in the structure, how to detect the defect accurately and efficiently is always an important problem. In this article, the honeycomb core, instead of being an obstacle to obtain the dispersion characteristic for traditional guided wave method, provides a way to calculate the wave propagation by being taken advantage of its space periodicity. By analyzing, simulating, and experimental testing, it is exhibited that there is a gap in the dispersion relation of the honeycomb structure which caused by the interaction between the local resonant vibration of the skins and the bending vibration of the structure. This gap disappears in the debonding area. Then a nondestructive testing method is proposed to detect the debonding defects based on this feature. The detection results of this proposed method are accord with that of ultrasonic C-scan. The results indicate that this method is suitable for detecting and locating the debonding defects in honeycomb structure with quite high sensitivity and efficiency, and it has a great potential to be widely used in filed test of honeycomb structure for its high feasibility. [ABSTRACT FROM AUTHOR]

As one of the primary noise sources of underwater-robots, the hydrodynamic-noise of the ducted-propeller (DP) originates from various unsteady flows in the flow-field. To investigate the coupling-mechanism between the flow-field and the acoustic-field of DP, this paper establishes a three-dimensional flow field-acoustic field coupling numerical calculation model based on the vortex-acoustic equation. It combines simulation and experimental research to investigate the unsteady flow-field of the DP. The mechanism of acoustic-wave generation and the distribution characteristics of the acoustic field are studied, and the DP's propagation law of hydrodynamic-noise is analyzed based on the field-synergy theory. The results show that the DP domain's vortex structure is mainly influenced by the tensile-distortion and Coriolis-force term. However, hydrodynamic-noise generation is closely related to the vortex, turbulent pulsation, and other unstable flows in the flow-field. The radiated noise of the propeller decreases and then increases with the increase of the inlet velocity-coefficient (IVC) and is smallest at the optimal efficiency point (J = 0.6). With the increase of IVC, the synergy of the propeller flow field-acoustic field is enhanced, the energy-loss of acoustic transmission increases, and the far-field radiation noise decreases. This paper provides a theoretical reference for suppressing the hydrodynamic-noise of the DP and acoustic-optimization design of the underwater-robots. • 3D flow field-acoustic field coupling CFD-simulation using vortex-acoustic theory. • DP's propagation law of hydrodynamic noise is analyzed using field synergy theory. • Reference study for the suppression of the hydrodynamic noise of the DP. • Reference study for the acoustic optimization design of the underwater robots. [ABSTRACT FROM AUTHOR]

Piezoelectric Shunt Oscillators (PSOs) are widely used in the passive and semi-active control of the vibration and acoustic radiation of flexible structures, due to PSOs' high electromechanical coupling coefficients, robustness, effectiveness and adjustability at low frequencies. Panel–Cavity–Panel System (PCPS) is a common type of flexible structures, such as interior panels and windows of automobiles. In this paper, a theoretical model of PCPS controlled by PSOs and its vibration equations are established. The vibroacoustic characteristics of PCPS, including sound absorption coefficient (SAC), energy loss coefficient (ELC) and transmission loss (TL), are calculated using a unified mathematical form based on the vibroacoustic radiation impedance matrix, damping matrix and displacement response of PCPS, while a lumped parameter model of PCPS is derived to simplify the comprehension and extension of PCPS. Then the finite element simulation is used to calculate the vibroacoustic characteristics of the PCPS, which achieves good agreement with theoretical results, while three basic regulation modes are also summarized and verified. The regulation mechanism of PCPS controlled by PSOs is further analyzed by the velocity response of each panel. Finally, experiments of PCPS controlled by PSOs with negative capacitors are conducted in a standing wave tube, at non-eigenfrequencies ranging from 70 Hz to 220 Hz. It is found in experiments that PSOs with negative capacitor can increase the TL of PCPS about 8 dB to 25 dB, which depends on the target frequency. SAC and ELC can also be increased, which means less acoustic energy is reflected and more acoustic energy is dissipated in the shunt circuits. • A theoretical model of Panel–Cavity–Panel System (PCPS) controlled by Piezoelectric Shunt Oscillators (PSOs) and its vibration equations are established. The vibroacoustic characteristics of PCPS are calculated using a unified mathematical, while a lumped parameter model is derived to simplify the comprehension and extension of PCPS. • The regulation mechanism of PCPS controlled by PSOs is further analyzed by the velocity response of each panel. • The experiments of PCPS controlled by PSOs with negative capacitors are conducted in a standing wave tube, at non-eigenfrequencies ranging from 70 Hz to 220 Hz. TL of PCPS can be thus increased by 8 dB to 25 dB, which depends on the target frequency. [ABSTRACT FROM AUTHOR]

Cavitation is a specific liquid dynamic phenomenon that usually occurs during the operation of hydraulic machinery. This phenomenon is a subject of great concern because it reduces mechanical efficiency, degrades and damages the surface of the propeller, and increases undesirable vibrations and noise emissions. These factors affect the service life and operational safety of hydraulic equipment. In this paper, a novel cavitation detection method with phase demodulation of ultrasonic signals is proposed. Firstly, the modulation of the fluid motion of the ultrasonic signal is analyzed. The algorithm describing the relationship between the ultrasonic phase and the spatial mean velocity of flow field is then investigated. Moreover, a classifier model based on support vector machine is established to identify the cavitation state. The performance of the proposed method is experimentally verified in the laboratory using 320 test samples. The successful recognition rate reaches 98%, which indicates good stability and accuracy for cavitation detection. The ultrasonic transducers are installed on the outer surface of the pipeline, which is believed to be more suitable for practical applications than hydroacoustics or other pressure and optical cavitation detection methods. Furthermore, the proposed method can be used to discriminate between laminar and turbulent flows in the pipeline. [ABSTRACT FROM AUTHOR]

Background Due to the lack of cutoff values validated for specific liver diseases, the purpose of this study was to set up specific magnetic resonance elastography ( MRE) cutoff values for asymptomatic liver fibrosis in alcoholic patients. Methods Ninety patients underwent 3 clinical exams. The liver stiffness was measured locally with the Fibroscan, and globally through cartographies of shear modulus generated with MRE. The Fibroscan method was chosen as the gold standard to classify the fibrosis. The liver score was also obtained with the Fibrometer A, and the diagnostic performance of the methods was analyzed with receiver-operating characteristic ( ROC) curves and cutoff values were calculated. Results Spearman correlation and area under the ROC curve revealed that MRE is a better diagnostic method than the Fibrometer A, to identify various levels of fibrosis. The results showed that the Fibrometer A was adapted for severe fibrosis. The MRE cutoff values are F1:2.20 kPa, F2:2.57 kPa, F3:3.31 kPa, and F4:4 kPa and were not influenced by the glutamic oxaloacetic transaminase level. By using the ultrasound cutoff values attributed for alcoholism, 66% of patients had a similar liver fibrosis diagnosis as the MRE cutoffs. However, both imaging techniques did not provide the same distribution for minor fibrosis. Conclusions None of the imaging techniques ( Fibroscan, MRE) could replace the gold standard of the biopsy. However, due to the risk and the unnecessary procedure for the present recruited alcoholic patients, the Fibroscan method was chosen as the reference. Since MRE is currently being used as a clinical exam, the present MRE cutoffs could aid clinicians with their diagnosis of liver fibrosis for alcoholism disease. [ABSTRACT FROM AUTHOR]