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•Monascus anka and Bacillus sp. were applied to conduct fermentation on GLs.•HPLC fingerprint combined with chemometric analyses can be well applied to quickly evaluate and control ...the mature degree of fermented products.•Gallic acid, quercetin-3-O-α-L-arabinopyranoside, quercetin, and kaempferol were identified as remarkable contributors during fermentation.•Fermentation degree was a key factor for obtaining high active fermented products.
Guava leaves (GLs) were processed by solid-state co-fermentation with Monascus anka and Bacillus sp., and the impact of the fermentation degree on the phenolic composition and their bioactivities was investigated. Three representative HPLC fingerprints of phenolic compositions from GLs can be clearly distinguished for the different fermentation degrees. Four characteristic compounds, including gallic acid, quercetin-3-O-α-L-arabinopyranoside, quercetin, and kaempferol, that significantly responded to the changes of bioactivity in the fermented GLs were identified as the marker components by principal component analysis. High levels of the four marker components in the HPLC fingerprints are an indication that the fermented GLs are mature. In addition, the correlation analysis confirmed that the total phenolic, total flavonoid, and the quercetin and kaempferol contents strongly correlated with its bioactivities. These results can provide a theoretical basis to quickly evaluate and control the mature degree of fermented products, which will help to obtain high bioactive fermented products.
Cancer metabolism research has recently been revived and its focus expanded from glucose and the Warburg's effects on other nutrients, such as glutamine. The underlying mechanism of oncogenic ...alterations of glutaminolysis remains unclear. Genetic alterations of EGFR are observed in ~50% of glioblastoma (GBM) patients, and have been found to play important roles in the metabolic abnormalities of GBM. In this study, we found that glutamine metabolism was upregulated after EGFR activation in a GDH1 (glutamate dehydrogenase 1)-dependent manner. Knockdown of GDH1 significantly reduced the cell proliferation, colony formation and tumorigenesis abilities of glioblastoma cells. Furthermore, we showed that GDH1-mediated glutaminolysis was involved in EGF-promoted cell proliferation. EGFR triggered the phosphorylation of ELK1 at Ser 383 through activating MEK/ERK signaling. Phosphorylated ELK1 enriched in the promoter of GDH1 to activate the transcription of GDH1, which then promoted glutamine metabolism. In addition, EGFR activation did not accelerate glutaminolysis in ELK1 knockdown or ELK1 Ser383-mutated cells. Collectively, our findings indicate that EGFR phosphorylates ELK1 to activate GDH1 transcription and glutaminolysis through MEK/ERK pathway, providing new insight into oncogenic alterations of glutamine metabolism.
Two-dimensional van der Waals heterostructures have good application prospects in solar energy conversion due to their excellent optoelectronic performance. In this work, the electronic structures of ...Sc2CF2/Sc2CCl2, Sc2CF2/Sc2CBr2, and Sc2CCl2/Sc2CBr2 heterostructures, as well as their properties in photocatalysis and photovoltaics, have been comprehensively studied using the first-principles method. Firstly, both of the three thermodynamically and dynamically stable heterostructures are found to have type-II band alignment with band gap values of 0.58 eV, 0.78 eV, and 1.35 eV. Meanwhile, the photogenerated carriers in Sc2CF2/Sc2CCl2 and Sc2CF2/Sc2CBr2 heterostructures are predicated to follow the direct Z-scheme path, enabling their abilities for water splitting. As for the Sc2CCl2/Sc2CBr2 heterostructure, its photovoltaic conversion efficiency is estimated to be 20.78%. Significantly, the light absorption coefficients of Sc2CF2/Sc2CCl2, Sc2CF2/Sc2CBr2, and Sc2CCl2/Sc2CBr2 heterostructures are enhanced more than those of the corresponding monolayers. Moreover, biaxial strains have been observed to considerably tune the aforementioned properties of heterostructures. All the theoretical results presented in this work demonstrate the application potential of Sc2CX2/Sc2CY2 (X, Y = F, Cl, Br) heterostructures in photocatalysis and photovoltaics.
Prenatal exposure to bisphenol A (BPA) and its analogues can affect fetal growth and development. However, epidemiologic findings were inconsistent and there was a lack of study for BPA analogues. We ...aimed to examine the associations between prenatal exposure to BPA, bisphenol B (BPB), bisphenol F (BPF), bisphenol S (BPS), and tetrabromobisphenol A (TBBPA) and birth size. 2023 mother-infant pairs were included in this study. The associations between serum bisphenol levels and birth size were analyzed by multivariate linear regression models. After adjusting for covariates, one log10-unit increase in serum BPA was correlated with a 32.10 g (95% CI: −61.10, −3.10) decrease in birth weight for all infants, and the inverse association was only observed in males when stratified analysis by gender. Additionally, higher BPF concentrations were associated with decreasing birth weight (P for trend = 0.031), ponderal index (P for trend = 0.021), and birth weight Z-scores (P for trend = 0.039) in all infants, and the inverse associations were also only observed in males when stratified analysis by gender. Similarly, higher TBBPA levels were also correlated with decreased birth weight (P for trend = 0.023). However, after gender stratification, higher TBBPA concentrations were associated with a decrease in birth weight (P for trend = 0.007), birth length (P for trend = 0.026), and birth weight Z-scores (P for trend = 0.039) in males. Our data suggested an inverse association of prenatal exposure to BPA, BPF, and TBBPA and birth size, which may be more pronounced in male infants.
•Associations of prenatal bisphenol exposure and birth size were examined.•Prenatal BPA, BPF, and TBBPA exposure was associated with birth size, which may be more pronounced in male infants.•While for BPB and BPS, no significant associations with birth size were found.
Using voltage-source converter high-voltage direct current (VSC-HVDC) to interconnect weak ac power systems has drawn much attention. Under the traditional vector control for the VSC that the ...response of AC voltage loop cannot match that of the active power loop may limit power transmission capability of the VSCs that interconnect with weak power systems. To enhance the power transmission capability and stability, this paper proposes a power compensation control that is based on the analysis of characteristics of power-voltage (PV) curves. This method can improve the damping control performance of the active power and the ac voltage by adjusting the compensated values adaptively. A small-signal model of the integrated system is established to study the performance of the proposed control method. The impact of the compensation coefficients and steady-state operating points on the system stability is studied. Motivated by an on-going back-to-back project in China, corresponding electromagnetic transient simulation models are constructed in MATLAB/Simulink environment to verify the effectiveness of the proposed method on the performance of operating limits, damping performance, disturbance withstanding capability, and fault ride-through capability.
•The solving model of optimum polarization angle is established.•On the premise of the optimum polarization angle, the images are captured.•The image captured based on polarization information ...optimizes the image processing.•The pose is solved non-iteratively according to the constraints of a parallelogram.
As for vision-based pose estimation, which is also known as the PnP problem, non-iterative algorithms are more efficient. Precise extraction of 2D projections of feature points is important. If the projections of the feature points are not accurately extracted, the pose estimation accuracy is reduced. Under the condition of natural light, a camera captures the images of feature points, and the existence of high-light regions in the image affects the extraction accuracy of 2D projections of feature points, which reduces the number of effective feature points and leads to poor pose estimation accuracy. In the redundant cases (n > 4), redundant feature points are introduced as additional information, increasing the number of effective feature points to reduce the impact of high-light regions and improve the pose estimation accuracy. For the non-redundant cases (n = 4), it was difficult to ensure pose estimation accuracy. To solve this problem, a non-iterative pose estimation method based on the optimum polarization angle via four corner points of a parallelogram was proposed in this study. First, a model for solving optimum polarization angle was established. Thereafter, on the premise of the optimum polarization angle, the images were captured. Finally, the projections of the four corner points of a parallelogram were extracted, and the object pose was solved non-iteratively according to the four corner points. The corner point extraction experimental results show that the slope difference between the two parallel sides of each parallelogram under the condition of optimum polarization angle is less than that under the condition of natural light, thereby proving the improvement of the imaging quality. Measurement accuracy verification experiments prove that our pose estimation algorithm and the optimum polarization angle is the best combination to improve the non-iterative pose estimation accuracy in non-redundant cases. In the measurement range of −60-+60°, the angle measurement error was less than ±0.0491°. In the measurement range of 0–20 mm, the displacement measurement error was less than ±0.0435 mm.
We have recently applied surface-enhanced Raman spectroscopy (SERS) for blood plasma analysis for non-invasive nasopharyngeal cancer detection and obtained good preliminary results. The aim of this ...study was to develop a more robust SERS spectroscopy based blood plasma analysis method for non-invasive gastric cancer detection. The effect of different laser polarizations (non-polarized, linear-polarized, right-handed circularly polarized, and left-handed circularly polarized) on blood plasma SERS spectroscopy was explored for the first time. Silver nanoparticles as the SERS-substrate were directly mixed with blood plasma to enhance the Raman scattering of various biomolecular constituents. High quality SERS spectra were obtained using a fiber optic probe and a dispersive type near infrared Raman system. Blood plasma samples from gastric cancer patients (
n
=
32) and healthy subjects (
n
=
33) were analyzed. The diagnostic performance for differentiating gastric cancer plasma from normal plasma was evaluated. Principal component analysis combined with linear discriminant analysis (LDA) of the obtained spectral data was used to develop diagnostic algorithms. Classification results obtained from cross-validation of the LDA model based on the four spectral data sets of different laser polarizations demonstrated different diagnostic sensitivities and specificities: 71.9% and 72.7% for non-polarized laser excitation, 75% and 87.9% for linear-polarized laser excitation, 81.3% and 78.8% for right-handed circularly polarized laser excitation, 100% and 97% for left-handed circularly polarized laser excitation. The results from this exploratory study demonstrated that plasma SERS spectroscopy with left-handed circularly polarized laser excitation has great promise of becoming a clinically useful diagnostic tool for non-invasive gastric cancer detection.
Ferroptosis is an iron-dependent form of cell death that is characterized by early lipid peroxidation and different from other forms of regulated cell death in terms of its genetic components, ...specific morphological features, and biochemical mechanisms. Different initiation pathways of ferroptosis have been reported, including inhibition of system X
, inactivation of glutathione-dependent peroxidase 4, and reduced glutathione levels, all of which ultimately promote the production of reactive oxygen species, particularly through enhanced lipid peroxidation. Although ferroptosis was first described in cancer cells, emerging evidence now links mechanisms of ferroptosis to many different diseases, including cerebral ischemia and brain hemorrhage. For example, neonatal brain injury is an important cause of developmental impairment and of permanent neurological deficits, and several types of cell death, including iron-dependent pathways, have been detected in the process of neonatal brain damage. Iron chelators and erythropoietin have both shown neuroprotective effects against neonatal brain injury. Here, we have summarized the potential relation between ferroptosis and neonatal brain injury, and according therapeutic intervention strategies.
•The line formed by every two calibration points is expressed by two independent constraints.•These two independent constraints are considered in the extrinsic parameters calibration.•There is no ...iterative step under the condition of ensuring the calibration accuracy.
The calibration accuracy of the binocular stereo vision system is important for precision measurement. The extrinsic parameters (structure parameters), which describe the relative position of the two cameras, need to be optimized before measurement. The optimization of extrinsic parameters is accomplished through iterations of minimizing an objective function. It is hard to decide the optimum objective function between various objective functions. The calibration accuracy is decreased when the objective function is incorrect, which can result in excessive optimization or fall into a local minimum (ambiguous solution), notably for planar targets. In this paper, we proposed a non-iterative calibration method for the extrinsic parameters of binocular stereo vision considering the line constraints of a planar target. Each line formed by every two calibration points can provide two independent constraints. Additional equations for solving the extrinsic parameters can be obtained using these constraints. We added these equations to the equations system established by the homography of the target plane and image plane. The extrinsic parameters of the binocular stereo vision system can be solved non-iteratively. Using the parameters calibrated by our method, greater improvements in the accuracy and stability of measurements occurred, compared to other existing methods. In the −45° to +45° measuring range, the maximum measurement error is no more than 0.037° and the average measurement error is no more than 0.022°. In the 0 to 28 mm measuring range, the maximum measurement error is no more than 0.039 mm and the average measurement error is no more than 0.012 mm. The maximum length measurement error is no more than 0.038 mm and the average length measurement error is no more than 0.011 mm while measuring a 240 × 180 mm2 target.
•Co-fermentation of Psidium guajava L. (PGL) leaves with Monascus and Bacillus promoted the release of bound polyphenolics.•Soluble and insoluble-bound polyphenols from PGL was successfully ...identified.•Soluble polyphenol from PGL exhibited higher antioxidant activities.•Soluble polyphenol from PGL exhibited higher protective effect against DNA damage.•Microbial co-fermentation way significantly increased the antioxidant capacities from PGL.
The leaves of Psidium guajava L. (PGL) were co-fermented with Monascus anka and bacillus sp. to promote the release of insoluble-bound polyphenol components. The variation tendency of polyphenols contents were tracked during fermentation. Polyphenol compounds from unfermented PGL (UPGL) and fermented PGL (FPGL) were identified by HPLC-TOF-ESI/MS. The antioxidant activities of polyphenols extracts from UPGL and FPGL were determined by different standard methods. The results indicated that total polyphenols and soluble polyphenols contents especially for quercetin were enhanced at the first 8days of fermentation. Polyphenol extracts from FPGL had higher antioxidant than that from UPGL. Soluble polyphenol extracts exhibited higher antioxidant activity and protective effect against Fenton-induced DNA oxidative damage compared to insoluble-bound polyphenol extracts. This microbial co-fermentation way significantly increased the antioxidant capacities of soluble polyphenols from PGL. Our study provided a new way to upgrade polyphenols or other bioactive compounds with higher health beneficial effects.
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