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Compared with humans, who have more powerful auditory ability in discriminating and identifying speakers in noisy environments, traditional forensic automatic speaker recognizers do not perform well when dealing with noisy recordings. This paper proposes a GMM-UBM Forensic Automatic Speaker Recognition (FASR) System to reduce the effect of noise on performance. The system uses Gammatone Frequency Cepstral Coefficients (GFCC) based on an auditory periphery model and also incorporates a Principal Component Analysis (PCA) algorithm. The system was tested and validated using Mandarin voice databases compromised with different levels of white noise and office noise. The performance of the system was compared with a baseline system using Mel Frequency Cepstral Coefficients (MFCC) and also PCA under the same conditions. The results show that the performance of the combined GFCC system achieved a substantial improvement when compared with the baseline MFCC system under conditions of a high level of office noise. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance LANGDU, a Chinese traditional herbal medicine, was the dried roots of Euphorbia prolifera Buch-Ham. The herbal medicine has been used as anti-cancer and anti-inflammatory drug in local folk medicine for several hundred years. Aim of the study P-glycoprotein (P-gp) is a transmembrane exporter, which can expel a variety of anti-cancer drugs. Over-expressed P-glycoprotein in cancer cells impairs the effect of cancer chemotherapy and results in multidrug resistance (MDR). To elucidate the effect of LANGDU on MDR cancer cells, the constituents of Euphorbia prolifera Buch-Ham were analyzed. We found that a myrsinol diterpene, J196-10-1 could reverse multidrug resistance. Materials and methods Cytotoxicity assays were performed to measure reversal efficiency of J196-10-1. Efflux assay, ATPase assay, and real-time PCR were used to elucidate the mechanism of the chemical. Results J196-10-1 could reverse the resistance to daunorubicin, vincristine, and topotecan effectively. The diterpene inhibited P-gp mediated efflux and did not alter transcription of the target gene significantly. The compound stimulated ATP hydrolysis at a low concentration and inhibited it at a high concentration. Conclusions J196-10-1 inhibits P-gp competitively and reverses P-gp induced MDR in breast cancer cells. [ABSTRACT FROM AUTHOR]

• One-step synthesis of tin oxide nanoflowers self-assembled by multilayer nanosheets. • Excellent selectivity for HCHO. • The gas sensing performance was enhanced by constructing Hierarchical SnO 2 Nanoflowers. • Good stability during 7 days. In this work, the hierarchical structure SnO 2 nanoflowers self-assembled by multilayer nanosheets were successfully prepared by a simple hydrothermal method. The sensor based on this material shows excellent performances, while the response toward 100 ppm formaldehyde (HCHO) is 34.6 at 300 °C, and the response for the other test gases is much lower. This is because the hierarchical structure can provide numerous oxygen adsorption sites and the gas efficient diffusion, which can ensure the sensing surfaces are immediately exposed to HCHO molecular because of the efficient diffusion pathway and make SnO 2 be a highly conducting state in the same time. [ABSTRACT FROM AUTHOR]

• We extracted Mel-spectrograms and MFCC individually, and fused them to address the deficiencies caused by the reduction in information dimension. • We constructed a dual-stream network architecture to separately learn temporal domain features and frequency domain features to improve the network's performance. • Through a series of experiments on the ASVspoof2019LA dataset, we validated the superiority of our approach. In recent years, logic-manipulated speech detection has predominantly relied on single-feature and single-channel networks, which fail to consider a broader range of acoustic features. To address this limitation, we propose a novel approach based on a dual-branch network that incorporates fused Mel features for detecting logic-manipulated speech. The structure of our network consists of three main components. Firstly, we extract Mel spectrograms and Mel-frequency cepstral coefficients (MFCC) to address the deficiencies caused by the reduction in the information dimension. Then, to better utilize these two types of features, we construct a dual-branch network framework that enables the separate learning of temporal and frequency domain characteristics. Finally, at the backend of the network, we fuse the feature vectors for decision-making. Experimental evaluations conducted on the ASVspoof2019LA dataset demonstrate the effectiveness and superiority of our proposed method compared to state-of-the-art models and other acoustic features. [ABSTRACT FROM AUTHOR]

The variation of groundwater level caused by tides is a unique feature of intertidal wind turbines (IWTs). The groundwater level affects the natural frequency of the IWTs' monopile by changing the seabed characteristics. Therefore, it is necessary to reveal the influence of groundwater level on the natural frequency of monopile to ensure the stable operation and maintenance of IWTs. Based on model experiments, the laws of the change in groundwater level and the number of groundwater level cycles on the first natural frequency of the monopile in fine sand foundation is revealed, and is explained according to the stiffness and damping characteristics of the fine sand foundation. Moreover, the stiffness and damping characteristics of the fine sand foundation have different effects on the first natural frequency under different variation states of groundwater level: The stiffness of sand foundation is the main factor affecting the first natural frequency; with the groundwater level rising, the influence of the damping of sand foundation on the first natural frequency is getting stronger. In the designing and maintenance of IWTs, the seabed groundwater level should be focused on. • The influence of groundwater level on the first natural frequency of monopile in sandy seabed is revealed. • The stiffness of sandy seabed is main factor affecting the natural frequency of monopile with groundwater level changing. • With groundwater level rising, the influence of the damping of seabed on the first natural frequency of monopile increases. [ABSTRACT FROM AUTHOR]

Hemodialysis patients exhibit anemia-related cerebral hyperperfusion and iron deposition (ID). However, the mechanisms underlying the pathology of cerebral ID are not clear. We investigated the role of cerebral blood flow (CBF) in the pathophysiology of cerebral ID in hemodialysis patients with anemia. This study recruited 33 hemodialysis patients with anemia and thirty-three healthy controls (HCs). All the subjects underwent quantitative susceptibility mapping (QSM) and arterial spin labeling (ASL) to measure ID and CBF in the cerebral nuclei. Furthermore, we evaluated lacunar infarction (LI), cerebral microbleeds, and total white matter hyperintensity volume (TWMHV). Hemodialysis patients with anemia showed significantly higher ID and CBF in some nuclei compared to the HCs after adjusting for age, sex, and total intracranial volume (TIV) [ P < 0.05, false discovery rate (FDR) corrected]. CBF showed a positive correlation with ID in both patients and HCs after adjustments for age, gender, and TIV (P < 0.05, FDR corrected). Serum phosphorus, calcium, TWMHV, hypertension, and dialysis duration were independently associated with ID (P < 0.05). Hemoglobin, serum phosphorus, and LI were independently associated with CBF (P < 0.05). Mediation analysis demonstrated that CBF mediated the effects between hemoglobin and ID. Our study demonstrated that CBF mediated aberrant cerebral ID in hemodialysis patients with anemia. [ABSTRACT FROM AUTHOR]

Background: The circle of Willis (CoW) plays a significant role in intracranial atherosclerosis (ICAS). This study investigated the relationship between different types of CoW, atherosclerosis plaque features, and acute ischemic stroke (AIS). Methods: We investigated 97 participants with AIS or transient ischemic attacks (TIA) underwent pre- and post-contrast 3T vessel wall cardiovascular magnetic resonance within 7 days of the onset of symptoms. The culprit plaque characteristics (including enhancement grade, enhancement ratio, high signal in T1, irregularity of plaque surface, and normalized wall index), and vessel remodeling (including arterial remodeling ratio and positive remodeling) for lesions were evaluated. The anatomic structures of the anterior and the posterior sections of the CoW (A-CoW and P-CoW) were also evaluated. The plaque features were compared among them. The plaque features were also compared between AIS and TIA patients. Finally, univariate and multivariate regression analysis was performed to evaluate the independent risk factors for AIS. Result: Patients with incomplete A-CoW showed a higher plaque enhancement ratio (P = 0.002), enhancement grade (P = 0.01), and normalized wall index (NWI) (P = 0.018) compared with the patients with complete A-CoW. A higher proportion of patients with incomplete symptomatic P-CoW demonstrated more culprit plaques with high T1 signals (HT1S) compared with those with complete P-CoW (P = 0.013). Incomplete A-CoW was associated with a higher enhancement grade of the culprit plaques [odds ratio (OR):3.84; 95% CI: 1.36–10.88, P = 0.011], after adjusting for clinical risk factors such as age, sex, smoking, hypertension, hyperlipemia, and diabetes mellitus. Incomplete symptomatic P-CoW was associated with a higher probability of HT1S (OR:3.88; 95% CI: 1.12–13.47, P = 0.033), after adjusting for clinical risk factors such as age, sex, smoking, hypertension, hyperlipemia, and diabetes mellitus. Furthermore, an irregularity of the plaque surface (OR: 6.24; 95% CI: 2.25–17.37, P < 0.001), and incomplete symptomatic P-CoW (OR: 8.03, 95% CI: 2.43–26.55, P = 0.001) were independently associated with AIS. Conclusions: This study demonstrated that incomplete A-CoW was associated with enhancement grade of the culprit plaque, and incomplete symptomatic side P-CoW was associated with the presence of HT1S of culprit plaque. Furthermore, an irregularity of plaque surface and incomplete symptomatic side P-CoW were associated with AIS. [ABSTRACT FROM AUTHOR]

The UHV DC tension insulator strings are often large‐tonnage suspension porcelain or glass insulators with high mechanical strength. The single insulator is heavy, so two workers working at the same time are required to make a replacement on insulator strings in live working conditions. One of the key problems that must be solved in live working conditions is to select an appropriate way to reach the working position and realize the potential transfer between two workers. In this paper, the electric field calculation model of live working of ±800 kV tension strings was established. The process that two workers enter and leave the working position along the tension string and different conditions that two workers replace insulators were simulated and analyzed, and distribution characteristics of the electric field of insulator strings and live workers were obtained. According to the calculation results, when the two workers replace the tension insulators in different tension strings, it is easy to realize the potential transfer, so as to reach the same potential for work. The study results of this paper provide a basis for the selection of replacement method of large‐tonnage single insulator by two workers, and a theoretical basis for UHV DC live working. [ABSTRACT FROM AUTHOR]

• QSM combined with semi-automatic algorithm - DPA can quantitatively measure CMBs. • We propose an index of CMBs - total iron burden to describe CMBs. • The total iron burden can reflect the internal component of CMBs. • PVWMH may be a risk factor for the total iron burden of CMBs. • The total iron burden of CMBs affects brain atrophy by mediated by PVWMH. The goal of this work was to explore the total iron burden of cerebral microbleeds (CMBs) using a semi-automatic quantitative susceptibility mapping and to establish its effect on brain atrophy through the mediating effect of white matter hyperintensities (WMH). A total of 95 community-dwelling people were enrolled. Quantitative susceptibility mapping (QSM) combined with a dynamic programming algorithm (DPA) was used to measure the characteristics of 1309 CMBs. WMH were evaluated according to the Fazekas scale, and brain atrophy was assessed using a 2D linear measurement method. Histogram analysis was used to explore the distribution of CMBs susceptibility, volume, and total iron burden, while a correlation analysis was used to explore the relationship between volume and susceptibility. Stepwise regression analysis was used to analyze the risk factors for CMBs and their contribution to brain atrophy. Mediation analysis was used to explore the interrelationship between CMBs and brain atrophy. We found that the frequency distribution of susceptibility of the CMBs was Gaussian in nature with a mean of 201 ppb and a standard deviation of 84 ppb; however, the volume and total iron burden of CMBs were more Rician in nature. A weak but significant correlation between the susceptibility and volume of CMBs was found (r = -0.113, P < 0.001). The periventricular WMH (PVWMH) was a risk factor for the presence of CMBs (number: β = 0.251, P = 0.014; volume: β = 0.237, P = 0.042; total iron burden: β = 0.238, P = 0.020) and was a risk factor for brain atrophy (third ventricle width: β = 0.325, P = 0.001; Evans's index: β = 0.323, P = 0.001). PVWMH had a significant mediating effect on the correlation between CMBs and brain atrophy. In conclusion, QSM along with the DPA can measure the total iron burden of CMBs. PVWMH might be a risk factor for CMBs and may mediate the effect of CMBs on brain atrophy. [ABSTRACT FROM AUTHOR]

• Simple synthesis of hollow Cu 2 O nanocages. • Low working temperature. • Good stability during 35 days. P-type metal oxide semiconductors with special morphology have received high expectation for their potential application in gas sensors. We have synthesized hollow dodecahedral Cu 2 O nanocages with exposed (1 1 1) planes by a simple solution growth approach at room temperature. Characterization results indicate that the diameters of Cu 2 O nanocages are about 200 nm. Gas sensing performance of the Cu 2 O nanocages is investigated towards ethanol gas. Remarkably, the response of Cu 2 O reaches 4.6 at a low working temperature of 250 °C when the concentration is 100 ppm. The unique structure of Cu 2 O benefits the sensing performance owing to its active (1 1 1) planes. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The methanol gas sensing property of the nitrogen-doped quantum dot/Ag-LaFeO 3 p-n heterojunction materials (NALPN) are advanced and the experimental findings are innovative. • The response of NALPN sensor to 5 ppm methanol is 73 and the maximum response to other gases is 5 at 92°C. • The gas sensitivity test results show NALPN is a good gas-sensitive material with high response, low operating temperature and good selectivity to 5 ppm methanol gas. Abstract The unique electronic properties (electron mobility and carrier lifetime) are key factors for metal oxide semiconductor devices that directly determine the device's performance and application. Electron mobility of metal oxide semiconductor has a certain impact on response and operating temperature of gas sensor. Heterojunction composites of carbon quantum dots (CQDs) and perovskite materials have attracted much attention due to their great potential for gas sensors. In this paper, a gas sensor for monitoring methanol gas was developed based on nitrogen-doped carbon quantum dot/Ag-LaFeO 3 (NCQDs/Ag-LaFeO 3) p-n heterojunction materials (NALPN). NCQDS and Ag-LaFeO 3 form a heterojunction, which improves the carrier transport ability and separation of electron-hole pairs. The surface of NCQDs contains COOH, optimize the selectivity of Ag-LaFeO 3 to methanol gas. Gas sensitivity test results show that the NALPN to 5 ppm methanol gas possessed high response (73), low operating temperature (92 °C) and good selectivity. These excellent properties prove that NALPN materials are the main competitors for future gas sensitive materials. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Excellent sensitivity and selectivity have been achieved. • The working temperature of the toluene gas sensor is relatively low. • The sensor shows good long-term stability. • Gas-sensing properties of Ag-LaFeO 3 are enhanced by microwave radiation and molecular imprinting technology. Abstract Highly sensitive and selective detection against toluene gas remains a tremendous challenge in gas sensor applications. In this work, a series of molecular imprinted Ag-LaFeO 3 nanoparticles (IAL NPs) were synthesized in a microwave-assisted colloidal route. Especially, the one prepared with optimal amount of imprint molecules (IAL-2 NPs) have a response of 24.0 to 5 ppm toluene at the optimum working temperature of 215 °C with negligible responses to the other test gases, exhibiting enhanced gas sensing properties for toluene gas at a relatively low working temperature. The improved performance can be attributed to the favorable effect of microwave radiation, the molecular imprinting structure and the sensitization of Ag, which illuminates that IAL-2 NPs is a potential candidate for toluene detection. [ABSTRACT FROM AUTHOR]

The structure of an offshore wind turbine accumulates damage during its service life, while its surrounding soil is continually scoured. However, the existing damage detection technique based on structural mode ignores scouring, which will cause damage misjudgment in engineering application. Therefore, the effect of scour depth on structural damage detection need to be studied urgently. In this paper, the pile and its surrounding soil are constructed into a vibration system, and the change of soil constraint state caused by scouring is reflected in structural mode. Based on that, a new structural damage detection method considering the pile-soil interaction is developed, which is suitable for engineering reality. Then, from a comparison between the calculated result and preset damage in the numerical simulations and model experiments, the proposed method is validated. The results show that the interference factors caused by scouring increase with the increase of scour depth, which causes the deterioration of damage identification effects gradually, and even masks the preset damage in the end. Finally, an optimized FE model based on the actual scour depth is presented, which reduces the number of interference factors and improves the effect of damage detection significantly. • A structural damage detection method considering pile-soil interaction and seabed scouring is proposed, which breaks through the limitations of the fix-end constraint. • This method can identify the damage of the structure under the constraint state that is closer to the actual scoured seabed, which is more meaningful for engineering. • The interference caused by scour increases with the increase of scour depth, which causes the deterioration of damage identification effects, and eventually masks the preset damage. • An optimized FE model based on the actual scour depth is presented, which improves the effect of damage detection significantly. [ABSTRACT FROM AUTHOR]

Field observations show that silt is not always loose and that silt consolidation is common. In the study reported here, the characteristics of pile scour in consolidated silt (CS) under clear-water conditions were investigated and compared with those in loose silt. Experiments were performed to study the dimensions of equilibrium scour holes in CS, and the results show that the scour depth and radius in CS are smaller than those in loose silt, but the slope angle in CS is larger and the scour depth is inversely proportional to the dry density. It is found that the scour characteristics in CS differ from those in commonly used fine sand and silt, and most of the existing scour equations cannot predict the scour depth in CS. A mathematical relationship between the scour hole dimensions and the maximum scour depth applicable to CS is established, and a new equation is proposed for computing the maximum scour depth in CS with an error of less than 25%. The present work offers theoretical guidance for the design of scour prevention of piles and scour hole repair in CS. • A series of pile scour experiments were conducted in consolidated silt with different dry densities and loose silt. • Explored the influence of consolidation effect of silt on the scour process and scour hole dimensions. • Proposed new calculation methods of scour hole dimensions and equilibrium scour depth of pile under consolidation silt. • The results show that the present method are in good agreement with the measured data. [ABSTRACT FROM AUTHOR]

Scour is ubiquitous in offshore wind farms and threatens the stable state of the natural frequency of offshore wind turbines. The foundation of offshore wind turbines is a layered seabed, which mainly consists of clay, silt, and fine sand layers. However, little published literature can be found on the natural frequencies of monopiles in layered foundations with scour. The objective of this study was to reveal the influence of scour in layered foundations on the natural frequencies of monopoles and study its mechanism based on the dynamic characteristics of layered foundations. Therefore, based on an actual layered seabed, three typical layered foundations were established, and the first natural frequency of the monopile in terms of sensitivity to scour as well as the ability to resist continuous scour in the layered foundations were revealed. Moreover, the experimental results were analysed based on the stiffness and damping variations of the layered foundations under scour conditions. Importantly, a competitive relationship between the stiffness and damping of the layered foundations on the variation of the first natural frequency with scour was found and elaborated for the first time. The competitive relationship was influenced by the proportion of clay in the layered foundation. • The first natural frequencies of monopiles in different layered foundations present different responses to scour and different resistance to continuous scour. • The stiffness characteristics and damping characteristics of the layered foundations present a competitive relationship in the response of first natural frequency of monopile to scour. • The competition relationship between the stiffness characteristics and damping characteristics is influenced by the proportion of sandy soil and clay in the layered foundations. [ABSTRACT FROM AUTHOR]

Viral myocarditis is a common disease that contributes to dilated cardiomyopathy or heart failure. Coxsackievirus B (CVB) is one of the major causative pathogens of viral myocarditis. Previous studies have shown that autophagy is exploited to promote CVB replication in cell lines. To study whether cardiac myocytes respond to CVB infection in a similar way, viral myocarditis was established by the inoculation of 3-week-old BALB/c mice with CVB3. Electron microscopic observation showed that autophagosome-like vesicles were induced in the cardiac myocytes of mice infected by CVB3 at 3, 5, and 7 days after viral infection. The lipidated microtubule-associated protein 1 light chain 3 (LC3), LC3-II, was also significantly increased in both myocardium and the cardiac myocytes extracted from the ventricles of mice infected with CVB3. The increased LC3-II coincided with high level of viral RNA and proteins in both myocardium and isolated cardiac myocytes. Moreover, viral protein synthesis was significantly decreased in primary cardiac myocytes by the treatment with 3-methyladenine, an inhibitor of autophagy. The expression and the phosphorylation of extracellular signal regulated kinase (ERK) were also increased in both myocardium and in the isolated cardiac myocytes of the virus-infected mice, while the interplay of ERK with autophagic response remains to be studied. This study demonstrated that cardiac myocytes respond to CVB3 infection by increased formation of autophagosomes in vivo, which might be exploited for viral replication. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Dastarcus helophoroides (Coleoptera: Bothrideridae) which consists of 13 PCGs, 22 tRNA genes, two rRNA genes and a non-coding region (D-loop), is sequenced for its nucleotide sequence of 15,878 bp (GenBank: KF811054.1 ). The genome has a typical gene order which is identical to other Coleoptera species. Except for COI gene generally starts with non-canonical initial codon, all protein-coding genes start with ATN codon and terminate with the stop codon TA(A) or TAG. The secondary structure of rrnL and rrnS consists of 48 helices (contains four newly proposed helices) and 35 helices (contains two newly proposed helices) respectively. All 22 tRNAs in D. helophoroides are predicted to fold into typical cloverleaf secondary structure, except trnS1 (AGN), in which the dihydrouracil arm (DHU arm) could not form stable stem-loop structure. Thirteen protein-coding genes (nucleotide dataset and nucleic acid dataset) of the available species (29 taxa) have been used to infer the phylogenetic relationships among these orders. Tenebrionoidea and Cucujoidea form a sister group, and D. helophoroides is classified into Cucujoidea (Bothrideridae). The study first research on the phylogenetic analyses involving to the D. helophoroides mitogenome, and the results strongly bolster the current morphology-based hypothesis. [ABSTRACT FROM AUTHOR]

Formaldehyde is known as the common interior air pollutants, which can cause great damages to the human respiratory system and neural system with a small amount. Thus, it is necessary to monitor formaldehyde accurately and in real time at near-room temperature. In this work, the porous CuO hierarchical microspheres were synthesized by microwave-assisted hydrothermal method with various reaction time. As the reaction time prolongs from 1 to 7 h, the initial self-assembled CuO microspheres changes to nanoplates-coated microspheres. For CuO-5, the response of reaches 32 towards 80 ppm formaldehyde at room temperature and it also exhibits good selectivity as the response values to other test gases are lower than 5 These performances prevail over those of the other CuO samples in this experiment. The reason can be concluded that the exposed crystal faces and the active sites are different with increasing hydrothermal reaction time, resulting in different gas sensing properties. This work investigate the dependence of morphology and exposed crystal faces on gas-sensing properties in detail. Image 1 • The porous CuO hierarchical microspheres were synthesized by an easy microwave-assisted hydrothermal method. • The operating temperature of the formaldehyde gas sensor is as low as 30 °C, realizing room temperature detection. • The response of the sample to 80 ppm formaldehyde is 32 with excellent selectivity. • The sensor showed good long-term stability with almost constant responses. [ABSTRACT FROM AUTHOR]

• The sensor based on H-SnO 2 @1.2%rGO has extremely high selectivity coefficients (>50) to the other interfering gases. • The sensor based on H-SnO 2 @1.2%rGO exhibits an ultrahigh response (435) to 10 ppm formaldehyde, which is more than 17 times higher compared to the pristine SnO 2. • Optimal temperature of the sensor is ultralow and 130 °C. • The preparation method is convenient, simple and cost-effective. In addition, the best ratio of SnO 2 and rGO was determined. • Excellent super-low theoretical detection limits (1 ppb) for sensors. Incorporating of semiconducting metal oxides and carbonaceous materials reasonably has been proven to be an effective method to improve the sensing properties for gas sensors. In this work, the novel reduced graphene oxide-wrapped hollow SnO 2 nanospheres (H-SnO 2 @rGO) composites are successfully synthesized via a simple hydrothermal method without any templates added. This unique hybrid structure is demonstrated to show significantly enhanced formaldehyde sensing performance compared to the pristine SnO 2 nanospheres. At an optimal temperature of 130°C, H-SnO 2 @1.2%rGO sensor exhibits an ultrahigh response (435) to 10 ppm formaldehyde, which is more than 17 times higher compared to the pristine SnO 2. Besides, it delivers excellent selectivity, low detection limit and fast response/recovery time. The synergistic effect of SnO 2 and rGO plays an important role in improving the sensing behavior. The enhancement mechanism responsible for the superior sensing properties of the nanocomposite is also discussed. [ABSTRACT FROM AUTHOR]