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Background: Prior neuroimaging studies on vestibular migraine (VM) have extensively certified the functional and structural alterations in multiple brain regions and networks. However, few studies have assessed the cerebral blood flow (CBF) in VM patients using arterial spin labeling (ASL). The present study aimed to investigate CBF and functional connectivity (FC) alterations in VM patients during interictal periods. Methods: We evaluated 52 VM patients and 46 healthy controls (HC) who received resting-state pseudo-continuous ASL and functional magnetic resonance imaging (fMRI) scanning. Comparisons of voxel-based CBF and seed-based FC were performed between the two groups. Brain regions showed significant group differences in CBF analyses were chosen as seeds in FC analyses. Additionally, the associations between abnormal imaging results and clinical features were explored. Results: Compared with HC, VM patients showed higher normalized CBF in the right precentral gyrus (PreCG), left postcentral gyrus (PostCG), left superior frontal gyrus and bilateral insular (p < 0.05, FDR corrected). Furthermore, VM patients exhibited increased FC between the right PreCG and areas of the left PostCG, left cuneus and right lingual gyrus (p < 0.05, FDR corrected). In addition, we observed decreased FC between the left insular and regions of the left thalamus and right anterior cingulate cortex, as well as increased FC between the left insular and right fusiform gyrus in VM patients (p < 0.05, FDR corrected). Moreover, these variations in brain perfusion and FC were significantly correlated with multiple clinical features including frequency of migraine symptoms, frequency of vestibular symptoms and disease duration of VM (all p < 0.05). Conclusions: Patients with VM during interictal period showed hyperperfusion and abnormal resting-state FC in brain regions potentially contributed to disrupted multi-sensory and autonomic processing, as well as impaired ocular motor control, pain modulation and emotional regulation. Our study provided novel insights into the complex neuropathology of VM from a CBF perspective. [ABSTRACT FROM AUTHOR]

Luster is one of the vital indexes in pearl grading. To find a fast, nondestructive, and low-cost grading method, optical coherence tomography (OCT) is introduced to predict the luster grade through the texture features. After background removal, flattening, and segmentation, the speckle pattern of the region of interest is described by seven kinds of feature textures, including center-symmetric auto-correlation (CSAC), fractal dimension (FD), Gabor, gray level co-occurrence matrix (GLCM), histogram of oriented gradients (HOG), laws texture energy (LAWS), and local binary patterns (LBP). To find the relations between speckle-derived texture features and luster grades, four Four groups of pearl samples were used in the experiment to detect texture differences based on support vector machines (SVMs) and random forest classifier (RFC)) for investigating the relations between speckle-derived texture features and luster grades. The precision, recall, F1-score, and accuracy are more significant than 0.9 in several simulations, even after dimension reduction. This demonstrates that the texture feature from OCT images can be applied to class the pearl luster based on speckle changes. [ABSTRACT FROM AUTHOR]

Background: CDC25B, as a member of the cell cycle regulating protein family, is located in the cytoplasm and is involved in the transition of the cell cycle and mitosis. CDC25B is highly expressed in various tumors and is a newly discovered oncogene. This study aimed to investigate the impact of CDC25B on mitoxantrone resistance in stomach adenocarcinoma (STAD) and its possible mechanisms. Methods: This study analyzed the expression of CDC25B and its potential transcription factor E2F3 in STAD, as well as the IC50 values of tumor tissues by bioinformatics analysis. Expression levels of CDC25B and E2F3 in STAD cells were measured by qRT-PCR. MTT was utilized to evaluate cell viability and IC50 values of STAD cells, and comet assay was utilized to analyze the level of DNA damage in STAD cells. Western blot was used to analyze the expression of DNA damage-related proteins. The targeting relationship between E2F3 and CDC25B was validated by dual-luciferase and ChIP assays. Results: Bioinformatics analysis and molecular experiments showed that CDC25B and E2F3 were highly expressed in STAD, and CDC25B was enriched in the mismatch repair and nucleotide excision repair pathways. The IC50 values of tumor tissues with high expression of CDC25B were relatively high. Dual-luciferase and ChIP assays confirmed that CDC25B could be transcriptionally activated by E2F3. Cell experiments revealed that CDC25B promoted mitoxantrone resistance in STAD cells by regulating DNA damage. Further research found that low expression of E2F3 inhibited mitoxantrone resistance in STAD cells by DNA damage, but overexpression of CDC25B reversed the impact of E2F3 knockdown on mitoxantrone resistance in STAD cells. Conclusion: This study confirmed a novel mechanism by which E2F3/CDC25B mediated DNA damage to promote mitoxantrone resistance in STAD cells, providing a new therapeutic target for STAD treatment. [ABSTRACT FROM AUTHOR]

Non-contact micro-manipulation tools have enabled invasion-free studies of fragile synthetic particles and biological cells. Rapid electrokinetic patterning (REP) traps target particles/cells, suspended in an electrolyte, on an electrode surface. This entrapment is electrokinetic in nature and thus depends strongly on the suspension medium's properties. REP has been well characterized for manipulating synthetic particles suspended in low concentration salt solutions (~ 2 mS/m). However, it is not studied as extensively for manipulating biological cells, which introduces an additional level of complexity due to their limited viability in hypotonic media. In this work, we discuss challenges posed by isotonic electrolytes and suggest solutions to enable REP manipulation in bio-relevant media. Various formulations of isotonic media (salt and sugar-based) are tested for their compatibility with REP. REP manipulation is observed in low concentration salt-based media such as 0.1× phosphate buffered saline (PBS) when the device electrodes are passivated with a dielectric layer. We also show manipulation of murine pancreatic cancer cells suspended in a sugar-based (8.5% w/v sucrose and 0.3% w/v dextrose) isotonic medium. The ability to trap mammalian cells and deposit them in custom patterns enables high-impact applications such as determining their biomechanical properties and 3D bioprinting for tissue scaffolding. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate changes in dynamic functional network connectivity (FNC) in patients with vestibular migraine (VM) and explore their relationship with clinical manifestations. Methods: Resting-state functional magnetic resonance imaging (rs-fMRI) data were scanned from 35 VM patients without peripheral vestibular lesion and 40 age-, sex- and education-matched healthy controls (HC). Independent component analysis (ICA), sliding window (SW) and k-means clustering analysis were performed to explore the difference in FNC and temporal characteristics between two groups. Additionally, Pearson's partial correlation analysis was adopted to investigate the relationship between clinical manifestations and rs-fMRI results in patients with VM. Results: Compared with HC, patients with VM showed increased FNC in pairs of extrastriate visual network (eVN)-ventral attention network (VAN), eVN-default mode network (DMN) and eVN-left frontoparietal network (lFPN), and exhibited decreased FNC in pairs of VAN-auditory network (AuN). The altered FNC was correlated with clinical manifestations of patients with VM. Additionally, we found increased mean dwell time and fractional windows in state 2 in VM patients compared with HC. Mean dwell time was positively correlated with headache impact test-6 (HIT-6) scores, fractional windows was positively associated with dizziness handicap inventory (DHI) scores. Conclusion: Our results indicated that patients with VM showed altered FNC primarily between sensory networks and networks related to cognitive, emotional and attention implementation, with more time spent in a state characterized by positive FNC between sensor cortex system and dorsal attention network (DAN). These findings could help reinforce the understanding on the neural mechanisms of VM. [ABSTRACT FROM AUTHOR]

Purpose: To characterize the altered brain function in patients with vestibular migraine (VM) using resting-state functional magnetic resonance imaging (fMRI). Methods: In this prospective study, fMRI images as well as clinical characteristics and behavioral scales were collected from 40 VM patients and 40 healthy controls (HC). All patients received neurological, neuro-otological, and conventional MRI examinations to exclude peripheral vestibular lesions, focal lesions, and other neurological diseases. Seed-based (bilateral parietal operculum cortex 2, OP2) functional connectivity (FC) and independent component analysis (ICA)-based functional network connectivity (FNC) were performed to investigate the brain functional changes in patients with VM. Additionally, the correlations between the altered FC/FNC and behavioral results were analyzed. Results: Compared with HC, patients with VM showed increased FC between the left OP2 and right precuneus and exhibited decreased FC between the left OP2 and left anterior cingulate cortex. We also observed increased FC between the right OP2 and regions of the right middle frontal gyrus and bilateral precuneus, as well as decreased FC between the bilateral OP2. Furthermore, patients with VM showed decreased FNC between visual network (VN) and networks of auditory and default mode, and exhibited increased FNC between VN and executive control network. A correlation analysis found that FC between the left OP2 and right precuneus was positively correlated with scores of dizziness handicap inventory (DHI) in patients with VM. Conclusion: The present study demonstrated altered brain function in patients with VM. [ABSTRACT FROM AUTHOR]

α-Ga2O3 film deposited on m-plane sapphire substrate by RF magnetron sputtering method was used to fabricate a solar-blind UV PD with traditional MSM structure. The optimum deposition temperature of the pure-phase (300) α-Ga2O3 film was confirmed to be 775 ℃ from the XRD, AFM and deposition rate analyses. The bandgap of the prepared α-Ga2O3 film was estimated to be 5.3 eV from the optical absorbance measurement. The (300) α-Ga2O3 film based PD exhibited a responsivity of 659.6 A/W and a photo-to-dark ratio of 1554 under 254 nm light illumination. The response time constants at bias voltage of 5 V were estimated to be (0.28, 1.52 s) and (0.04, 0.62 s), respectively. [ABSTRACT FROM AUTHOR]

Ba4Al5 is an electride in which excess anion electrons are confined in the two-dimensional interlayer region. Here, we carry out a systematical study on the electronic, optical, and plasmonic properties of Ba4Al5 using the first-principles calculations. It is found that the metallic Ba4Al5 has a relatively low cleavage energy (~ 0.77 J/m2), suggesting a weak interlayer interaction and the easiness of exfoliation. Importantly, Ba4Al5 possesses a low work function on the (001) surface and exhibit excellent optical properties, such as high light absorption coefficient with weak optical anisotropy that becomes stronger when decreasing the thickness. It is further found that Ba4Al5 is also a suitable plasmonic material which can be used in the near-infrared frequency range. [ABSTRACT FROM AUTHOR]

Progression, prognosis, and therapeutic strategy of stomach adenocarcinoma (STAD) have a close connection with tumor microenvironment (TME). Thus, it is pivotal to delve into the TME and immune-related genes, which may bring possibilities for improving patient's prognosis. TCGA-STAD dataset was analyzed to acquire differentially expressed lncRNAs in tumor samples, which were overlapped with the immune-related lncRNA datasets in the ImmLnc database. Twenty-six lncRNAs related to STAD immunity and patient's prognosis were acquired by univariate Cox analysis. Following lncRNA expression patterns, STAD samples could be classified into two clusters with completely different immune patterns. We performed multivariate Cox regression analysis on lncRNAs to identify 7-feature lncRNAs and constructed a corresponding prognostic model. The model validity was verified by survival analysis and ROC curve in validation and training sets. To explore connection between model and TME and tumor drug resistance, this study analyzed differences in immune cell infiltration between samples from high- and low-risk groups and then revealed immune cells follicular helper with significant differences in tumor tissue infiltration. Analysis of resistance to chemotherapeutic drugs revealed that samples in the high-risk group had resistance to cisplatin, doxorubicin, bleomycin, and gemcitabine. Through univariate and multivariate Cox analyses, we manifested that risk score could be an independent prognostic factor. Combining risk score and clinical factors, a nomogram was constructed to accurately predict patient's prognosis. This model can effectively predict prognosis, TME, and drug resistance of STAD patients, which may provide a reference for tumor development evaluation and precise treatment for clinical STAD. [ABSTRACT FROM AUTHOR]

Fungal infection is a pre-harvest and post-harvest crisis for maize kernels and infection detection at early stage is still a difficult point. The feasibility of optical coherence tomography (OCT) for imaging mold-contamination on maize kernel at early stage is investigated. OCT technique provides high-resolution 2D tomographic images of micro-structure of maize and realizes immediate, automated, and non-destructive detection of mold by proposed method. After denoising, edge detection, smoothing, and flatten, thin pericarp layer is cropped and extracted. Then, the number of non-zero pixels on the upper boundary is calculated and the float threshold is used to classify whether there are mildew pixels in a certain column. All the experimental results suggest that mold contaminated maize kernel can be detected and marked by monitoring near surface layers combined with our proposed method. The OCT approach is suitable for fast, nondestructive diagnosis of mold at early stage, which may potentially lead to significant cost savings and better control of the spread of mold in the food industry. [ABSTRACT FROM AUTHOR]

Purpose: To explore the functional connectivity (FC) between the bilateral thalamus and the other brain regions in patients with vestibular migraine (VM). Methods: Resting-state fMRI and 3D-T1 data were collected from 37 patients with VM during the interictal period and 44 age-, gender-, and years of education-matched healthy controls (HC). The FC of the bilateral thalamus was analyzed using a standard seed-based whole-brain correlation method. Furthermore, the correlations between thalamus FC and clinical characteristics of patients were investigated using Pearson's partial correlation. Results: Compared with HC, VM patients showed decreased FC between the left thalamus and the left anterior cingulate cortex (ACC), bilateral insular and right supplementary motor cortex. We also observed decreased FC between the right thalamus and the left insular and ACC in VM patients. Furthermore, patients with VM also exhibited increased FC between the left thalamus and the right precuneus and middle frontal gyrus, between the right thalamus and superior parietal lobule. FC between the right thalamus and the left insular was negatively correlated with disease duration (p = 0.019, r = − 0.399), FC between the left thalamus and the left ACC was negatively correlated with HIT-6 score (p = 0.004, r = − 0.484). Conclusion: VM patients showed altered FC between thalamus and brain regions involved in pain, vestibular and visual processing, which are associated with specific clinical features. Specifically, VM patients showed reduced thalamo-pain and thallamo-vestibular pathways, while exhibited enhanced thalamo-visual pathway, which provided first insight into the underlying functional brain connectivity in VM patients. [ABSTRACT FROM AUTHOR]

Laser hardening is an important branch of laser surface hardening technology, which is widely used in metallurgy, transportation, machinery manufacturing, aerospace and other fields. At present, relying entirely on experience or process trial-and-error method, it can not effectively reveal the transient mechanism of laser quenching of disk laser, which is not conducive to shortening the research and development cycle and saving costs. The numerical simulation provides an effective way to obtain the dynamic evolution law of multi-field coupling in laser quenching process. In this paper, a thermo-mechanical coupling model of ASTM 1045 laser quenching process by disk laser is established. In the model, the temperature-dependent physical parameters were calculated by CALPHAD method. The transient law of temperature and microstructural transformation during quenching was obtained by solving the model. The formation and transformation degree of martensite were characterized by the dynamic changes of the depth and width of quenched transformation layer. The quenching structure and transformation hardening law were observed by Axioskop 2 SEM and Zeiss-IGMA HD FE-SEM to verify the accuracy of the simulation results. On this basis, the process parameters of laser quenching were sampled by Monte-Carlo method based on response surface methodology. The sensitivity effects of different process parameters on the temperature field and phase change field of laser quenching were analyzed, which laid a theoretical foundation for the optimization of process parameters. (1) Establish a thermo-mechanical coupling model for quenching process of ASTM 1045, and the sensitivity of the system is calculated. (2) The model can accurately reproduce the transient process of temperature and phase transformation field during laser quenching. (3) The laser power and laser incident angle are positively correlated with the response value. (4) The spot diameter and scanning speed are negatively correlated with response value. (5) The model can effectively calculate the sensitivity of laser quenching, predict the width and depth of quenching layer, and optimize process parameters. [ABSTRACT FROM AUTHOR]

Slight postharvest bruises of loquats remarkably affect the quality and shelf life of the fruits, but they are difficult to identify using visual inspection. Sub-surface structural changes in cells caused by mechanical injury or impact can be detected using spectroscopy-based methods from different angles. Optical coherence tomography (OCT), a non-destructive technology, can acquire cross-sectional images to analyze sub-surface structures of loquats, thus offering the potential to identify fruit bruises. This study proposes an automated OCT image processing method for extracting large cells from loquat images, which involves a series of steps including image denoising, boundary detection, filtering, binarization, segmentation, and region selection. Parenchyma cells in loquat tissue were visualized and characterized, and the five-cell morphological parameters, including total cell surface area, average cell surface area, average cell Feret diameter, equivalent diameter, and cell amount were measured. The bruised and non-bruised loquat groups showed significant differences in the total cell surface area and cell amount, suggesting that these two parameters might be used as indictors for bruise identification. No significant differences in other parameters were observed between the two groups. The microcosm approach proposed in this study sheds some light on ways to improve fruit quality evaluation. Overall, combined with appropriate image processing, OCT is an efficient and non-destructive tool for loquat bruise detection. The proposed strategy might also be expanded to other agricultural applications. [ABSTRACT FROM AUTHOR]

In this work, the capability of newly developed hydrophilic interaction liquid chromatography (HILIC) coupled with matrix-assisted laser desorption/ionization-mass spectrometric imaging (MALDI-MSI) platform for quantitative analysis of N-glycans has been demonstrated. As a proof-of-principle experiment, heavy and light stable-isotope labeled hydrazide reagents labeled maltodextrin ladder were used to demonstrate the feasibility of the HILIC-MALDI-MSI platform for reliable quantitative analysis of N-glycans. MALDI-MSI analysis by an Orbitrap mass spectrometer enabled high-resolution and high-sensitivity detection of N-glycans eluted from HILIC column, allowing the re-construction of LC chromatograms as well as accurate mass measurements for structural inference. MALDI-MSI analysis of the collected LC traces showed that the chromatographic resolution was preserved. The N-glycans released from human serum was used to demonstrate the utility of this novel platform in quantitative analysis of N-glycans from a complex sample. Benefiting from the minimized ion suppression provided by HILIC separation, comparison between MALDI-MS and the newly developed platform HILIC-MALDI-MSI revealed that HILIC-MALDI-MSI provided higher N-glycan coverage as well as better quantitation accuracy in the quantitative analysis of N-glycans released from human serum. [ABSTRACT FROM AUTHOR]

Highly transparent Ga doped ZnO thin films were prepared on (0001) sapphire substrates by pulsed laser deposition. Hall-effect measurement reveals that electron concentration of the ZnO films can be controlled between 10 and 10 cm by adjusting Ga contents in the targets. Optical measurements show the transmittance is above 60 % in the near-infrared wavelength region for all Ga doped ZnO films. Meanwhile, these films also have high crystal quality and smooth surface when the electron concentration up to 10 cm, suggesting that the Ga doped ZnO is a promising material for using as transparent electrode for near infrared optoelectronic devices. [ABSTRACT FROM AUTHOR]

Owing a much higher breakdown field (8 MV/cm) and Baliga’s figure-of-merit (3444) than other hot wide bandgap semiconductor materials such as 4H-SiC and GaN, β-Ga2O3 is regarded as a new promising candidate for high-power electronic applications. The highest electrical breakdown strength (3.8 MV/cm) of metal-oxide-semiconductor field-effect transistors (MOSFET) is demonstrated by the Air Force Research Laboratory, which has a 20 nm Al2O3 gate dielectric and a sub-micron gate-drain spacing of 0.6 µm. Among the device structure, the interface control between channel and gate is a key factor for MOSFET. The better the lattice matching between the gate and the channel layers, the better the interface structure between them will be. In this paper, Fe-doped β-Ga2O3 thin films have been grown at various substrate temperatures and oxygen partial pressures. The resistance increases markedly compared with pure β-Ga2O3, exhibiting the characteristic of high insulation. This study suggests that Fe-doped β-Ga2O3 thin film can be used as homogeneous epitaxial gate dielectric material to fabricate Ga2O3-based high-power devices. [ABSTRACT FROM AUTHOR]

Ba4Al5 is an electride in which excess anion electrons are confined in the two-dimensional interlayer region. Here, we carry out a systematical study on the electronic, optical, and plasmonic properties of Ba4Al5 using the first-principles calculations. It is found that the metallic Ba4Al5 has a relatively low cleavage energy (~ 0.77 J/m2), suggesting a weak interlayer interaction and the easiness of exfoliation. Importantly, Ba4Al5 possesses a low work function on the (001) surface and exhibit excellent optical properties, such as high light absorption coefficient with weak optical anisotropy that becomes stronger when decreasing the thickness. It is further found that Ba4Al5 is also a suitable plasmonic material which can be used in the near-infrared frequency range. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) is a health problem that concerns people around the world. CDC25B is an essential cell cycle regulatory factor that is overexpressed in a variety of tumor cells. CDC25B plays a vital part in the progression and proliferation of malignant tumors. However, it is not yet clear that how CDC25B affects the stemness of GC cells. The study used bioinformatics to detect the expression of E2F1 and CDC25B in GC tissues and their correlation, as well as pathways enriched by CDC25B. We detected the expression of E2F1 and CDC25B in GC cell lines using quantitative reverse transcription polymerase chain reaction and tested the combination relationship between E2F1 and CDC25B using chromatin immunoprecipitation (ChIP) and dual-luciferase assays. We measured cell viability using CCK-8 assay, evaluated sphere-forming efficiency using sphere formation assay, and determined cell proliferation ability using colony formation assay. We also analyzed the expression of stemness markers and MAPK pathway-related proteins using western blot. In GC tissues and cells, CDC25B was upregulated. Silencing CDC25B could affect the MAPK pathway, thereby repressing the proliferation and stemness of GC cells. As predicted by bioinformatics, CDC25B had an upstream transcription factor, E2F1, which also had a high expression level in GC. Dual-luciferase and ChIP assays confirmed the combination relationship between the two. Rescue experiments uncovered that overexpression of CDC25B could reverse the impact induced by E2F1 knockdown on proliferation and stemness of cells. In conclusion, E2F1 could activate CDC25B transcription to regulate the MAPK pathway and enhance the proliferation and stemness of GC cells. We revealed a potential regulatory pathway of stemness of GC cells that was mediated by CDC25B, providing new ideas for improving and innovating GC treatment. [ABSTRACT FROM AUTHOR]