Speech signal enhancement based on deep learning in distributed acoustic sensing.

The fidelity of a speech signal deteriorates severely in a distributed acoustic sensing (DAS) system due to the influence of the random noise. In order to improve the measurement accuracy, we have theoretically and experimentally compared and analyzed the performance of the speech signal with and without a recognition and reconstruction method-based deep learning technique. A complex convolution recurrent network (CCRN) algorithm based on complex spectral mapping is constructed to enhance the information identification of speech signals. Experimental results show that the random noise can be suppressed and the recognition capability of speech information can be strengthened by the proposed method. The random noise intensity of a speech signal collected by the DAS system is attenuated by approximately 20 dB and the average scale-invariant signal-to-distortion ratio (SI-SDR) is improved by 51.97 dB. Compared with other speech signal enhancement methods, the higher SI-SDR can be demonstrated by using the proposed method. It has been effective to accomplish high-fidelity and high-quality speech signal enhancement in the DAS system, which is a significant step toward a high-performance DAS system for practical applications.

Inversion method for soil moisture content based on a distributed fiber optic acoustic sensing system.

The traditional measurement method can't achieve real-time monitoring of soil moisture content (SMC) within a two-dimensional area. To solve the above problems, we propose a rapid SMC monitoring method for two-dimensional area based on distributed acoustic sensing (DAS). DAS demodulates the backward Rayleigh scattering signal containing seismic wave sound velocity information from the active seismic source. The folding ruler approximation is employed to calculate the sound velocity of the soil, which is then inverted to determine the soil moisture content. The experiment measured the soil within a two-dimensional area formed by the seismic source and the acoustic sensing optical cable. The sensing optical cable and the active seismic source are organized into a two-dimensional area and the measurement range is 3 × 10 m with 33 points. The SMC ranges from 15% to 40%. The experiment shows that the absolute error between the measured values obtained by DAS and the water cut meter is 7%. This experiment verifies the feasibility of using the Rayleigh scattering properties to invert SMC and provides a new method for real-time monitoring of SMC in a large area.

Isolation and Cultivation of Vascular Smooth Muscle Cells from the Mouse Circle of Willis.

INTRODUCTION: Culturing cerebrovascular smooth muscle cells (CVSMCs) in vitro can provide a model for studying many cerebrovascular diseases. This study describes a convenient and efficient method to obtain mouse CVSMCs by enzyme digestion. METHODS: Mouse circle of Willis was isolated, digested, and cultured with platelet-derived growth factor-BB (PDGF-BB) to promote CVSMC growth, and CVSMCs were identified by morphology, immunofluorescence analysis, and flow cytometry. The effect of PDGF-BB on vascular smooth muscle cell (VSMC) proliferation was evaluated by cell counting kit (CCK)-8 assay, morphological observations, Western blotting, and flow cytometry. RESULTS: CVSMCs cultured in a PDGF-BB-free culture medium had a typical peak-to-valley growth pattern after approximately 14 days. Immunofluorescence staining and flow cytometry detected strong positive expression of the cell type-specific markers alpha-smooth muscle actin (α-SMA), smooth muscle myosin heavy chain 11 (SMMHC), smooth muscle protein 22 (SM22), calponin, and desmin. In the CCK-8 assay and Western blotting, cells incubated with PDGF-BB had significantly enhanced proliferation compared to those without PDGF-BB. CONCLUSION: We obtained highly purified VSMCs from the mouse circle of Willis using simple methods, providing experimental materials for studying the pathogenesis and treatment of neurovascular diseases in vitro. Moreover, the experimental efficiency improved with PDGF-BB, shortening the cell cultivation period.

Long-distance Φ-OTDR with a flexible frequency response based on time division multiplexing.

In this study, a long-distance phase-sensitive optical time domain reflectometry (Φ-OTDR) with a flexible frequency response based on time division multiplexing is proposed and experimentally demonstrated. Distributed flexible frequency vibration sensing over long distance can be realized by reconfiguring the system layout in a time-division-multiplexed manner by re-routing the Rayleigh backscattered signals for segmented processing with extra erbium-doped fiber amplifiers added only instead of any other complex signal amplification or pulse modulation mechanisms. Through time-division-multiplexed reconfiguration, the tradeoff between sensing distance and vibration frequency response in Φ-OTDR system is largely relieved. Compared with the traditional system layout, the proposed system allows a flexible frequency response in each sensing fiber segment without any crosstalk among them. In experiments, distributed vibration sensing with a frequency response up to 4.5 kHz is achieved over a sensing distance of 60km by the proposed system, which is not possible in a conventional Φ-OTDR system. Furthermore, the frequency response flexibility of the proposed system is further verified by successfully identifying a vibration event with a frequency of up to 20 kHz at the end of a 52-km-long fiber.

Broadening frequency response of a distributed sparse-wideband vibration sensing via a time-division multi-frequency sub-Nyquist sampling.

The maximum detectable vibration frequency response range is inversely related with the sensing fiber length in direct-detection intensity-measuring coherent optical time domain reflectometry (DI-COTDR). Unlike the conventional uniform sampling, the pulse repetition rate is modulated in a time-division manner so that a multi-frequency sub-Nyquist sampling is realized along every point of the sensing fiber. A 24-kHz vibration signal can be detected and recovered by a compressive sensing technique using sampling pulses with repetition rate lower than 5-kHz, which is ten-fold lower compared to that required in the conventional uniform sampling method. Also, a multi-frequency vibration signal can be identified and recovered by this technique. The proposed method can break through the theoretical maximum detection frequency of traditional systems without any hardware modification. Therefore, such a method is of great significance for broadening the frequency response range of the distributed sparse-wideband vibration sensing.

Distributed sparse signal sensing based on compressive sensing OFDR.

The maximum detectable vibration frequency of an optical frequency domain reflectometry (OFDR) system is limited by the tunable rate of the laser source. Unlike uniform sampling with the time-resolved method, the sampling frequency is randomly modulated so that the vibration signal applied on the interrogation fiber is sampled by a multi-frequency sub-Nyquist sampling method and reconstructed by the compressive sensing technique. First, we give a full treatment to prove that the proposed method has the same performance as the conventional method. Second, in a further proof-of-concept experiment, the measurable frequency of a sparse signal is achieved up to 200 Hz with a sweeping rate of 40 nm/s. This method can recover the vibration signal with sampling rates less than that required by the Nyquist sampling theory, which is a significant step toward a high-performance OFDR system, especially for evaluating the intrinsic frequency of the object's structural condition.

Promising Targets for Cancer Immunotherapy: TLRs, RLRs, and STING-Mediated Innate Immune Pathways.

Malignant cancers employ diverse and intricate immune evasion strategies, which lead to inadequately effective responses of many clinical cancer therapies. However, emerging data suggest that activation of the tolerant innate immune system in cancer patients is able, at least partially, to counteract tumor-induced immunosuppression, which indicates triggering of the innate immune response as a novel immunotherapeutic strategy may result in improved therapeutic outcomes for cancer patients. The promising innate immune targets include Toll-like Receptors (TLRs), RIG-I-like Receptors (RLRs), and Stimulator of Interferon Genes (STING). This review discusses the antitumor properties of TLRs, RLRs, and STING-mediated innate immune pathways, as well as the promising innate immune targets for potential application in cancer immunotherapy.

Metabolomics and pharmacodynamic analysis unveil the therapeutic role of icaritin on osteoporosis rats.

Osteoporosis is a systemic metabolic bone disease characterized by a reduction in bone mass resulting from multifactorial causes. Icaritin (ICT), a flavonoid glycoside, exhibits a multitude of effects on bone tissue. To examine the influence of ICT on bone trabecular loss in vivo, ovariectomized (OVX) rats were utilized. The ability of ICT to mitigate bone trabecular loss and the underlying anti-osteoporotic pathways were assessed using ovariectomy-induced osteoporosis rats. Furthermore, we gain insights into the osteoprotective mechanisms of ICT on osteoporosis by conducting UPLC-Orbitrap-MS-based metabolomics of rat urine. The results of experiments demonstrated a significant attenuation of bone trabecular loss, as well as improvements in biochemical indices, biomechanical parameters, and microstructure in the ICT administered group compared to the OVX group. Moreover, metabolomics results suggested that the ICT treatment adjusted 33 different metabolites, which associated with the metabolism of amino acids, lipids, and energy. The findings suggest that the anti-osteoporosis effect of ICT may be related to the activation of PI3K/AKT signal and the inhibition of TLR4 pathway regulated by metabonomics. These results contribute to a better understanding of the therapeutic potential of ICT in the treatment of osteoporosis.

Secondary metabolites and their bioactivities from Paecilomyces gunnii YMF1.00003.

Four new polyketides (1-4) and seven known compounds (5-11) including three polyketides and four sterols were isolated from the fermented extracts of Paecilomyces gunnii YMF1.00003. The new chemical structures were determined through the analysis of the nuclear magnetic resonance and high-resolution electrospray ionization mass spectrometry, and their configurations were subsequently confirmed by nuclear overhauser effect spectroscopy, the calculated electronic circular dichroism (ECD) spectra, and quantum chemical calculations of the NMR data (qcc NMR). Based on the results of pre-activity screening and compound structure target prediction, certain metabolites were assayed to evaluate their cytotoxic and protein kinase Cα inhibitory activities. Results indicated that 3ß-hydroxy-7α-methoxy-5α,6α-epoxy-8(14),22E-dien-ergosta (8) exhibited potent cytotoxic activity, with half-maximal inhibitory concentration values of 3.00 ± 0.27 to 15.69 ± 0.61 µM against five tumor cells, respectively. The new compound gunniiol A (1) showed weak cytotoxic activity at a concentration of 40 µM. At a concentration of 20 µg/mL, compounds 1, 6, and 7 exhibited protein kinase Cα inhibition by 43.63, 40.93, and 57.66%, respectively. This study is the first to report steroids demonstrating good cytotoxicity and polyketides exhibiting inhibitory activity against protein kinase Cα from the extracts of P. gunnii.

Pyroptosis Induction with Nanosonosensitizer-Augmented Sonodynamic Therapy Combined with PD-L1 Blockade Boosts Efficacy against Liver Cancer.

Induction of pyroptosis can promote anti-PD-L1 therapeutic efficacy due to the release of pro-inflammatory cytokines, but current approaches can cause off target toxicity. Herein, a phthalocyanine-conjugated mesoporous silicate nanoparticle (PMSN) is designed for amplifying sonodynamic therapy (SDT) to augment oxidative stress and induce robust pyroptosis in tumors. The sub-10 nm diameter structure and c(RGDyC)-PEGylated modification enhance tumor targeting and renal clearance. The unique porous architecture of PMSN doubles ROS yield and enhances pyroptotic cell populations in tumors (25.0%) via a cavitation effect. PMSN-mediated SDT treatment efficiently reduces tumor mass and suppressed residual tumors in treated and distant sites by synergizing with PD-L1 blockade (85.93% and 77.09%, respectively). Furthermore, loading the chemotherapeutic, doxorubicin, into PMSN intensifies SDT-pyroptotic effects and increased efficacy. This is the first report of the use of SDT regimens to induce pyroptosis in liver cancer. This noninvasive and effective strategy has potential for clinical translation.

Application of three-dimensional material CZIF-8/CS-MS as adsorbents for the determination of plant growth regulators in Schisandra chinensis.

In this study, we employed a melamine sponge (MS) as the skeleton material and utilized carbonized ZIF-8 (CZIF-8) and chitosan (CS) as the raw materials to prepare CZIF-8/CS-MS, a novel material featuring a three-dimensional interconnected porous network. The resulting CZIF-8/CS-MS material possesses a unique porous structure, significant specific surface area and abundant active sites. These characteristics make CZIF-8/CS-MS a promising absorbent for selective purification of plant growth regulators (PGRs) including 1-naphthlcetic acid (NAA), naphthoxyacetic acid (NOA), 4-chlorophenoxyacetic acid (4-CPA), 2,4-dichlorophenoxyacetic acid (2,4-D). After optimizing the extraction conditions, excellent linearity (r > 0.9994) was observed within a wide linear range of 1-100 ng/mL using ultra high performance liquid chromatography-tandem quadrupole mass spectrometry. The detection limits (LODs) and limits of quantification (LOQs) were found to be in the range of 0.013-0.154 ng/mL and 0.044-0.515 ng/mL, respectively. Additionally, the relative recovery of Schisandra chinensis fruit samples was determined to be 89.7-99.4 %, with a relative standard deviation (RSDs) of ≤ 8.4 % (n = 3). Compared to other methods, this approach offers a multitude of benefits, which include but are not limited to exceptional sensitivity, reduced sample volume requirements, low LODs, a comparable linear range, and high reproducibility. The findings of this study pave the way for exploring novel functionalized sponge columns, which leverage the integration of nano-sorbent materials and coating agents, for the purpose of analyzing PGRs within intricate matrix samples.

Major Strategies for Spatial Control of Ultrasound-Driven Gene Expression to Enhance Therapeutic Specificity.

A major challenge of gene therapy is to achieve highly specific transgene expression in tissues of interest with minimized off-target expression. Ultrasound in combination with microbubbles can transiently increase permeability of desired cells or tissues and thereby facilitate gene transfer. This kind of ultrasound-driven transgene expression has gained increasing attention due to its deep tissue penetration and high spatiotemporal resolution. However, successful genetic manipulation in vivo with ultrasound need to well optimize various aspects involved in this process. Ultrasound parameters, microbubble dose, and gene vectors need to be optimized for highly increased transgene expression in the cells of interest. Conversely, the potential off-target transgene expression and toxicities need to be reduced by modification of gene vectors and/or promoter sequence. This review will discuss some major strategies for enhanced specificity of the ultrasound-mediated gene transfer in vivo. Five major strategies will be discussed, including the integration of real-time imaging methods, local injection, targeted microbubbles loaded with nucleic acids, stealth nanocarriers, and cell-specific promoter. The advantages and limitations of each strategy were outlined, hoping to provide a guideline for researchers in achieving high specific ultrasound-driven gene expression.

Application of a three dimensional polyethyleneimine functionalized graphene oxide aerogel as an adsorbent for the determination of phytohormones in ginseng.

Aerogels have attracted considerable attention in sample pretreatment for their outstanding properties, such as the unique porous structure, large surface area and abundant modifiable active sites. The present research reports a three-dimensional interconnected porous network aerogel (PEI-AGO) manufactured based on graphene oxide (GO), polyethyleneimine (PEI) and agar as basic materials through a vacuum freeze-drying treatment. The PEI-AGO aerogel exhibits great potential as a solid phase extraction adsorbent for the selective purification of six endogenous plant hormones in conjunction with high performance liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS). Several factors affecting the extraction efficiency were investigated. Under the optimized extraction conditions, a wide linear range of 0.5-100 ng mL-1 with a good linearity (r > 0.9934) was observed. Low limits of detection (LODs) and limits of quantification (LOQs) were obtained in the range of 0.032-0.155 ng mL-1 and 0.107-0.518 ng mL-1, respectively. Furthermore, the relative recoveries for spiked ginseng samples exhibited remarkable consistency, ranging from 90.2% to 117.6%, with a relative standard deviation (RSD) of ≤9.4% (n = 3). In summary, PEI-AGO has proven to be an effective adsorbent for the pretreatment and enrichment of phytohormones which can be used for the determination of trace endogenous acidic plant hormones in ginseng leaves.

Identification of anti-inflammatory components in Panax ginseng of Sijunzi Decoction based on spectrum-effect relationship.

Objective: This study aimed to identify the main medicinal active components of Panax ginseng (P. ginseng) in the compatibility environment of clinical application. For this purpose, the anti-inflammatory ingredients of P. ginseng were investigated based on its therapeutic effect in Sijunzi Decoction (SJD) which is a widely used traditional Chinese formula. Methods: The fingerprints of 10 batches of SJD consisting of different sources of P. ginseng were established by UPLC technique to investigate the chemical components. At the same time, the anti-inflammatory effects of these components were evaluated by dextran sulfate sodium-induced ulcerative colitis mouse model. Grey relational analysis was applied to explore the correlation degree between fingerprints and anti-inflammatory effects in SJD. Lipopolysaccharide-stimulated RAW264.7 murine macrophages were established to evaluate the anti-inflammatory action of the screened effective substances of P. ginseng. Results: According to grey relational analysis, notoginsenoside R1, ginsenoside Rg2 and ginsenoside Rb3 of P. ginseng were the major anti-inflammatory contributions in SJD. They had been proven to be closely associated with the anti-inflammatory process of SJD and displayed a close effect compared with SJD by LPS-stimulated RAW264.7 murine macrophages. Conclusion: Our work provides a general strategy for exploring the pharmacological ingredients of P. ginseng in traditional Chinese formulas which is beneficial for establishing the quality standards of traditional herbs in traditional Chinese medicine prescription based on their clinical therapeutic effect.

ErbB2-upregulated HK1 and HK2 promote breast cancer cell proliferation, migration and invasion.

ErbB2 is overexpressed in 15-20% of breast cancer, which is associated with malignancy and poor prognosis. We previously reported that ErbB2 supports malignant progression of breast cancer by upregulating lactate dehydrogenase A (LDHA), an important enzyme in glycolysis. However, whether ErbB2 promotes breast cancer progression through other glycolytic enzymes remains unclear. Hexokinase 1 (HK1) and hexokinase 2 (HK2) are the first rate-limiting enzymes of glycolysis and both of them are increased in breast cancer. Here, we aim to investigate whether ErbB2 upregulates HK1 and HK2 and the role of HK1 and HK2 in the malignant progression of ErbB2-overexpressing breast cancer. In current study, we found that the mRNA level of ErbB2 was positively correlated with that of HK1 and HK2, respectively. Moreover, ErbB2 upregulated the protein levels of HK1 and HK2 in breast cancer cells. We also found that both siHK1 and siHK2 significantly inhibited the proliferation, migration and invasion of ErbB2-overexpressing breast cancer cells. Taken together, our findings suggested that ErbB2 promoted the malignant progression of breast cancer cells by upregulating HK1 and HK2, and HK1 and HK2 might serve as promising therapeutic targets for ErbB2-overexpressing breast cancer.

Effects of Magnesium Imbalance on Root Growth and Nutrient Absorption in Different Genotypes of Vegetable Crops.

Magnesium (Mg) plays a crucial role in crop growth, but how Mg supply level affects root growth and nutrient absorption in vegetable crops with different genotypes has not been sufficiently investigated. In this study, the responses of tomato (Solanum lycopersicum L.) and cucumber (Cucumis sativus L.) crops to different levels of Mg supply were explored. Four levels of Mg treatment (i.e., 0.2, 1.0, 2.0, 3.0 mmol/L) were applied under hydroponic conditions, denoted as Mg0.2, Mg1, Mg2, and Mg3, respectively. The results showed that with increasing Mg levels, the plant biomass, root growth, and nutrient accumulation in both vegetable crops all increased until reaching their maximum values under the Mg2 treatment and then decreased. The total biomass per tomato plant of Mg2 treatment was 30.9%, 14.0%, and 14.0% higher than that of Mg0.2, Mg1, and Mg3 treatments, respectively, and greater increases were observed in cucumber plant biomass (by 54.3%, 17.4%, and 19.9%, respectively). Compared with the Mg0.2 treatment, the potassium (K) and calcium (Ca) contents in various plant parts of both crops remarkably decreased under the Mg3 treatment. This change was accompanied by prominently increased Mg contents in various plant parts and para-hydroxybenzoic acid and oxalic acid contents in root exudates. Irrespective of Mg level, plant biomass, root growth, nutrient accumulation, and root exudation of organic acids were all higher in tomato plants than in cucumber plants. Our findings indicate that excessive Mg supply promotes the roots to exude phenolic acids and hinders the plants from absorbing K and Ca in different genotypes of vegetable crops despite no effect on Mg absorption. A nutritional deficiency of Mg stimulates root exudation of organic acids and increases the types of exuded organic acids, which could facilitate plant adaption to Mg stress. In terms of root growth and nutrient absorption, tomato plants outperform cucumber plants under low and medium Mg levels, but the latter crop is more tolerant to Mg excess.

Transcriptomic analysis of the cerebral hippocampal tissue in spontaneously hypertensive rats exposed to acute hypobaric hypoxia: associations with inflammation and energy metabolism.

We evaluated the effect of acute hypobaric hypoxia (AHH) on the hippocampal region of the brain in early-stage spontaneously hypertensive male rats. The rats were classified into a control (ground level; ~ 400 m altitude) group and an AHH experimental group placed in an animal hypobaric chamber at a simulated altitude of 5500 m for 24 h. RNA-Seq analysis of the brains and hippocampi showed that differentially expressed genes (DEGs) were primarily associated with ossification, fibrillar collagen trimer, and platelet-derived growth factor binding. The DEGs were classified into functional categories including general function prediction, translation, ribosomal structure and biogenesis, replication, recombination, and repair. Pathway enrichment analysis revealed that the DEGs were primarily associated with relaxin signaling, PI3K-Akt signaling, and amoebiasis pathways. Protein-protein interaction network analysis indicated that 48 DEGs were involved in both inflammation and energy metabolism. Further, we performed validation experiments to show that nine DEGs were closely associated with inflammation and energy metabolism, of which two (Vegfa and Angpt2) and seven (Acta2, Nfkbia, Col1a1, Edn1, Itga1, Ngfr, and Sgk1) genes showed up and downregulated expression, respectively. Collectively, these results indicated that inflammation and energy metabolism-associated gene expression in the hippocampus was altered in early-stage hypertension upon AHH exposure.

Recent advances in emerging application of functional materials in sample pretreatment methods for liquid chromatography-mass spectrometry analysis of plant growth regulators: A mini-review.

Plant growth regulators (PGRs) are a class of small molecular compounds, which can remarkably affect the physiological process of plants. The complex plant matrix along with a wide polarity range and unstable chemical properties of PGRs hinder their trace analysis. In order to obtain a reliable and accurate result, a sample pretreatment process must be carried out, including eliminating the interference of the matrix effect and pre-concentrating the analytes. In recent years, the research of functional materials in sample pretreatment has experienced rapid growth. This review comprehensively overviews recent development in functional materials covering one-dimensional materials, two-dimensional materials, and three-dimensional materials applied in the pretreatment of PGRs before liquid chromatography-mass spectrometry (LC-MS) analysis. Besides, the advantages and limitations of the above functionalized enrichment materials are discussed, and their future trends have been prospected. The work could be helpful to bring new insights for researchers engaged in functional materials in sample pretreatment of PGRs based on LC-MS.

In situ analysis of surface composition and meteorology at the Zhurong landing site on Mars.

The Zhurong rover of the Tianwen-1 mission landed in southern Utopia Planitia, providing a unique window into the evolutionary history of the Martian lowlands. During its first 110 sols, Zhurong investigated and categorized surface targets into igneous rocks, lithified duricrusts, cemented duricrusts, soils and sands. The lithified duricrusts, analysed by using laser-induced breakdown spectroscopy onboard Zhurong, show elevated water contents and distinct compositions from those of igneous rocks. The cemented duricrusts are likely formed via water vapor-frost cycling at the atmosphere-soil interface, as supported by the local meteorological conditions. Soils and sands contain elevated magnesium and water, attributed to both hydrated magnesium salts and adsorbed water. The compositional and meteorological evidence indicates potential Amazonian brine activities and present-day water vapor cycling at the soil-atmosphere interface. Searching for further clues to water-related activities and determining the water source by Zhurong are critical to constrain the volatile evolution history at the landing site.

Metabolites and Their Bioactivities from the Genus Cordyceps.

The Cordyceps genus is a group of ascomycete parasitic fungi, and all known species of this genus are endoparasites; they mainly feed on insects or arthropods and a few feed on other fungi. Fungi of this genus have evolved highly specific and complex mechanisms to escape their host's immune system and coordinate their life cycle coefficients with those of their hosts for survival and reproduction; this mechanism has led to the production of distinctive metabolites in response to the host's defenses. Herein, we review approximately 131 metabolites discovered in the genus Cordyceps (including mycelium, fruiting bodies and fungal complexes) in the past 15 years, which can be used as an important source for new drug research and development. We summarize chemical structures, bioactivity and the potential application of these natural metabolites. We have excluded some reports that originally belonged to Cordyceps, but whose taxonomic attribution is no longer the Cordyceps genus. This can and will serve as a resource for drug discovery.