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This study employed optical microscopy (OM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) to investigate the impact of vanadium (V) on the microstructure and mechanical properties of gray cast iron (GCI) HT250. Additionally, Thermo-Calc software was employed to explore the influence of V on the solidification process. The results indicate that adding trace amounts of V in GCI forms a face-centered cubic VC phase, with the precipitation temperature of the VC phase gradually increasing. When the V content reaches 0.28 wt%, the VC phase begins to precipitate during the eutectic reaction. The incorporation of V consumes carbon, reducing the graphite content and promoting the formation of type D graphite. As the V content increases, there is an enlargement in the pearlite area ratio, a decrease in the pearlite layer spacing, and a reduction in the size of eutectic cells. These microstructural alterations lead to enhanced mechanical properties. The tensile strength peaks at 336 MPa with a V content of 0.77 wt%, representing a 29% increase compared to samples without added V. Similarly, the Vickers hardness increases with increasing V content, reaching a peak of 373 HV at 0.92 wt% V, a 27% increase compared to samples without V addition. However, at this point, the tensile strength decreases to 322 MPa.

Toxoplasma gondii (T. gondii) is a worldwide zoonotic parasite that can infect almost warm-blood animals, including humans, which seriously affect the health of host. Cats are known to be the only definitive host of T. gondii and continuously excrete highly infectious oocysts. This parasite carried by the companion animals leads to a great public health risk. However, there is little information on epidemiology of T. gondii in urban cats in Kunming, Southwest China. In the present study, a total of 231 serum and fecal samples were collected in Kunming aera, and then seroprevalence of T. gondii IgG antibodies in serum and molecular investigation in feces were analyzed to elucidate T. gondii infection in urban cats. The results revealed that 168 of 231 cats (72.7%) were positive for T. gondii antibodies, and 1 of 74 cat feces (1.4%) also showed a positive PCR for T. gondii DNA. The positive fecal sample was sequenced and then phylogenetically analyzed, and the isolate of T. gondii in the present study was closely related to T. gondii strain CN. In addition, the food, water and age of cats were identified as the risk factor for seropositivity. Overall, our findings indicate the widespread occurrence of T. gondii infection in urban cats in Kunming, Southwest China and identify food, water and age are the risk factors associated with T. gondii infection, which can provide effective information for developing strategies to prevent and control this zoonosis.

Abstract Background Oral infection with cysts is the main transmission route of Toxoplasma gondii (T. gondii), which leads to lethal intestinal inflammation. It has been widely recognized that T. gondii infection alters the composition and metabolism of the gut microbiota, thereby affecting the progression of toxoplasmosis. However, the potential mechanisms remain unclear. In our previous study, there was a decrease in the severity of toxoplasmosis after T. gondii α-amylase (α-AMY) was knocked out. Here, we established mouse models of ME49 and Δα-amy cyst infection and then took advantage of 16S rRNA gene sequencing and metabolomics analysis to identify specific gut microbiota-related metabolites that mitigate T. gondii-induced intestinal inflammation and analyzed the underlying mechanism. Results There were significant differences in the intestinal inflammation between ME49 cyst- and Δα-amy cyst-infected mice, and transferring feces from mice infected with Δα-amy cysts into antibiotic-treated mice mitigated colitis caused by T. gondii infection. 16S rRNA gene sequencing showed that the relative abundances of gut bacteria, such as Lactobacillus and Bacteroides, Bifidobacterium, [Prevotella], Paraprevotella and Macellibacteroides, were enriched in mice challenged with Δα-amy cysts. Spearman correlation analysis between gut microbiota and metabolites indicated that some fatty acids, including azelaic acid, suberic acid, alpha-linolenic acid (ALA), and citramalic acid, were highly positively correlated with the identified bacterial genera. Both oral administration of ALA and fecal microbiota transplantation (FMT) decreased the expression of pro-inflammatory cytokines and restrained the MyD88/NF-κB pathway, which mitigated colitis and ultimately improved host survival. Furthermore, transferring feces from mice treated with ALA reshaped the colonization of beneficial bacteria, such as Enterobacteriaceae, Proteobacteria, Shigella, Lactobacillus, and Enterococcus. Conclusions The present findings demonstrate that the host gut microbiota is closely associated with the severity of T. gondii infection. We provide the first evidence that ALA can alleviate T. gondii-induced colitis by improving the dysregulation of the host gut microbiota and suppressing the production of pro-inflammatory cytokines via the MyD88/NF-κB pathway. Our study provides new insight into the medical application of ALA for the treatment of lethal intestinal inflammation caused by Toxoplasma infection. Video Abstract

Introduction: High concentrations of nonesterified fatty acids (NEFA) is the key of characteristic of fatty liver in dairy cows. Therefore, the aim of this study was to investigate the effect of high concentration of NEFA on lipid metabolism in hepatocytes through the lipidomic approach and molecular biology techniques.Methods: Stimulate AML-12 cells with different concentrations of NEFA, observe the cellular lipid accumulation, and select 0.6 mM NEFA stimulation concentration for subsequent experiments. Collect cells for lipidomics analysis.Results: High concentration of NEFA (0.6–2.4 mM) significantly reduced the cell viability in a concentration-dependent manner, indicating that high concentrations of NEFA have lipotoxicity on hepatocytes. In addition, NEFA promoted triglycerides (TAG) accumulation, increased the mRNA expression of the lipogenic molecules SREBP1c and FASN, and decreased the mRNA expression of lipolytic molecules CPT1A and HSL in hepatocytes. Mechanistically, high concentration of NEFA induced lipid metabolism disorders in hepatocytes by regulating metabolic pathways such as glycerol phospholipid metabolism, glycosyl phosphatidylinositol anchored biosynthesis, triglyceride metabolism, sphingolipid metabolism, and inositol phosphate metabolism.Discussion: High concentration of NEFA is lipotoxic to cells, promoting lipid accumulation. LPE (18:2), LPE (18:3), LPE (18:1) via glycerophospholipid metabolism, glycosylphosphatidylinositol (GPI)-anchor biosynthesis, glycerolipid metabolism, sphingolipid metabolism, and inositol phosphate metabolism, indicating their potential regulation role in the pathogenesis of fatty liver.

We propose a novel configuration for nonvolatile and reconfigurable tuning of surface lattice resonances (SLRs) based on thin films of phase-change material Ge2Sb2Te5 (GST). The configuration is composed of gold nanorod array embedded in a thin GST film. Results show that, an extremely wide SLR wavelength tuning range reaching 1600 nm, large tuning figure of merit of 21, and high SLR quality factors of 47 and 17 can be achieved in the mid-infrared regime when GST transits from the amorphous state into the crystalline state. The effects of the GST layer thicknesses on the SLR tuning performance are discussed, and the performances of several modified configurations are compared. We expect this work will advance the engineering of SLR tuning based on phase-change materials and promote its applications especially in nanolasing and narrowband filtering.

We propose a nonvolatile, reconfigurable, and narrowband mid-infrared bandpass filter based on surface lattice resonance in phase-change material Ge2Sb2Te5. The proposed filter is composed of a two-dimensional gold nanorod array embedded in a thick Ge2Sb2Te5 film. Results show that when Ge2Sb2Te5 transits from the amorphous state to the crystalline state, the narrowband reflection spectrum of the proposed filter is tuned from 3.197 μm to 4.795 μm, covering the majority of the mid-infrared regime, the peak reflectance decreases from 72.6% to 25.8%, and the corresponding quality factor decreases from 19.6 to 10.3. We show that the spectral tuning range can be adjusted by varying the incidence angle or the lattice period. By properly designing the gold nanorod sizes, we also show that the quality factor can be greatly increased to 70 at the cost of relatively smaller peak reflection efficiencies, and that the peak reflection efficiency can be further increased to 80% at the cost of relatively smaller quality factors. We expect that this work will advance the engineering of Ge2Sb2Te5-based nonvalatile tunable surface lattice resonances and will promote their applications especially in reconfigurable narrowband filters.

Research on Mobile-Assisted Language Learning (MALL) has mostly focused on investigating the effectiveness and physical nature of mobile technology or the psychological conditions of learners. Studies of MALL that associate the fundamental principles of the human cognitive learning process is comparatively less common. Despite years of formal instruction, speaking a second language remains a challenge for beginner learners of Chinese as a Second Language (CSL) in Malaysian International Schools. To help explain this, a framework of Mobile-Assisted Second Language Learning (MASLL) is developed to explain the cross-channel mental representation process in acquiring the speaking skills of a second language, using mobile phones. A total of 30 middle-year school learners from Malaysian International Schools underwent a quantitative, quasi-experimental pilot study. Learners with only the auditory stimuli outscored learners with the auditory-visual stimuli, with a mean difference of 4.87 in the gain scores. Whilst recognising the importance of auditory-visual stimuli during the learning phase, these findings highlight the importance of activating cross-channel mental representation during the interface and acquisition phases. A larger sample is needed to further validate these findings. Future studies on neuroscience, which localise the brainwave analysis, will be useful in providing visual explanation of the human cognitive processes and memory coding in acquiring the speaking skills of a second language.

Photoacoustic (PA) signals carry much information related to the physical parameters of a sample, such as its optical, thermal, acoustic, and elastic properties. These physical parameters synchronously make their own contributions to PA signals. It is difficult to distinguish the contributions of different physical parameters to the mixed PA signals. To separate these parameters and to extract the featured information, we report herein a means of dissecting the transient PA signal using time-frequency analysis in a forward detection model. The simulated and experimental results indicate that the features of different physical parameters related to the sample can be qualitatively extracted from the mixed PA signals. [ABSTRACT FROM AUTHOR]

This study aims to present a noninvasive prostate cancer screening methods using serum surface-enhanced Raman scattering (SERS) and support vector machine (SVM) techniques through peripheral blood sample. SERS measurements are performed using serum samples from 93 prostate cancer patients and 68 healthy volunteers by silver nanoparticles. Three types of kernel functions including linear, polynomial, and Gaussian radial basis function (RBF) are employed to build SVM diagnostic models for classifying measured SERS spectra. For comparably evaluating the performance of SVM classification models, the standard multivariate statistic analysis method of principal component analysis (PCA) is also applied to classify the same datasets. The study results show that for the RBF kernel SVM diagnostic model, the diagnostic accuracy of 98.1% is acquired, which is superior to the results of 91.3% obtained from PCA methods. The receiver operating characteristic curve of diagnostic models further confirm above research results. This study demonstrates that label-free serum SERS analysis technique combined with SVM diagnostic algorithm has great potential for noninvasive prostate cancer screening. [ABSTRACT FROM AUTHOR]

An innovative wavelength division multiplex-radio over fiber-passive optical network architecture for multiple access points (AP) based on multitone generation and triple sextupling frequency is proposed and demonstrated. A dual-drive Mach-Zehnder modulator (DD-MZM) is utilized to realize the multitone generation. Even sidebands are suppressed to make the adjacent frequency separation twice the frequency of the local oscillator by adjusting the modulation voltage of the DD-MZM. Due to adopting three fiber Bragg gratings to reflect the unmodulated sidebands for uplink communications source free at optical network unit (ONU), is achieved. The system can support at least three APs at one ONU simultaneously with a 30 km single-mode fiber (SMF) transmission and 5 Gb/s data rate both for uplink and downlink communications. The theoretical analysis and simulation results show the architecture has an excellent performance and will be a promising candidate in future hybrid access networks. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new physical method in combination with mixed solution of thiazone and polyethylene glycol 400 (thiazone PEG 400 solution) penetration into tissue to assess the skin optical clearing . Four treatments were performed: (1) control group (C); (2) polyethylene glycol 400 (PEG400); (3) 0.25% thiazone (0.25%T); (4) 0.25% thiazone and 5-min ultrasound (0.25%T/SP). The diffuse reflectance spectra and imaging depth of human skin in vivo at different times were measured by spectroscopy and optical coherence tomography (OCT). The optical clearing efficacy of skin was qualitatively and quantitatively analyzed. The results showed that the diffuse reflectance at 540 nm of samples at 10 min after being treated by 0.25%T/SP decreased by approximately 15.51%, whereas, 0.46%, 4.73% and 5.75% were received in C, PEG400 and 0.25%T, respectively. And at 60 min, the decrease in diffuse reflectance of samples in 0.25%T/SP is about 2.22-fold, 1.20-fold compared with that of the samples in PEG 400 and 0.25%T, at 540 nm, respectively. Simultaneously, 0.25%T/SP results in 41.33% increase in OCT 1/e light penetration depth after 60 min. There was a significant difference in the optical clearing effect on skin between ultrasound-mixed solution of thiazone in combination with PEG 400 and the mixed solution ( P < 0.05). [ABSTRACT FROM AUTHOR]

Heavy water gas (DO gas) which owns special structure property, can generate terahertz radiation by optically pumping technology, and its 385 μm wavelength radiation can be widely used. In this research, on the base of semi-classical density matrix theory, we set up a three-level energy system as its theoretical model, a TEA-CO laser 9R (22) output line (λ = 9.26 μm) acted as pumping source, DO gas molecules were operating medium, the expressions of pumping absorption coefficient G and Terahertz signal gain coefficient G were deduced. It was shown that the gain of Terahertz signal was related with the energy-level parameters of operating molecules and some operating parameters of the Terahertz laser cavity, mainly including cavity length. By means of iteration method, the output power density of Terahertz pulse signal was calculated numerically. Changing the parameter of cavity length and keeping others steady, the relationship curve between the output power intensity (Is) of Terahertz pulse laser and the operating cavity length (L) was obtained. The curve showed that the power intensity (Is) increased with cavity length (L) in a certain range, but decreased when the length (L) exceeded some value because of the absorption effect, and there was an optimal cavity length for the highest output power. We used a grating tuned TEA-CO laser as pumping power and a sample tube of variable length in 70-160 cm as terahertz laser operating cavity to experiment. The results of theoretical calculation and experiment matched with each other, and it is helpful for miniaturizing terahertz laser volume to make it practical. [ABSTRACT FROM AUTHOR]

An ideal diagnostic system for the tumor tissues should be able to detect and define the location of tumor tissues and the early development of malignant diseases. There is great need for enhancement of imaging ability to tumor tissues. Optical coherence tomography (OCT) is used in detection and location of varied tumor tissues. In order to improve the sensitivity and specificity of an OCT image, hematoporphyrin as a new type of contrast agent was used in this study. The orthotopic graft model of gastric cancer in nude mice was used. The image formations of the tumor tissues without and with injection of hematoporphyrin in vivo were obtained by an OCT system at a 1310 nm central wavelength. The experimental results showed that the tumor tissues accumulated with hematoporphyrin have an ability of light absorption which results in the increase of signal attenuation in the gastric cancer tissues, and that the boundary between the tumor tissues and surrounding normal tissues was perfectly defined owing to the accumulation of hematoporphyrin. From the experimental results, it is found that hematoporphyrin, a photosensitizing agent, could be used as a contrast agent for OCT imaging of tumor tissues, which offer an effective OCT image method for clinical detection and localization of tumor tissues in vivo. [ABSTRACT FROM AUTHOR]

We demonstrate an integral gated mode single photon detector at telecom wavelengths. The charge number of an avalanche pulse rather than the peak current is monitored for single photon detection. The transient spikes in conventional gated mode operation are cancelled completely by integrating, which enables one to effectively improve the performance of single photon detector with the same avalanche photodiode. This method achieved a detection efficiency of 29.9% at the dark count probability per gate equal to 5.57 × 10[?]6/gate (1.11 × 10[?]6 ns[?]1) at 1550 nm. [ABSTRACT FROM AUTHOR]

Confocal micro-Raman spectroscopy is employed to study the diffusion process of dimethyl sulfoxide (DMSO) in porcine skin optical clearing. The variation of DMSO concentration with time at different depths of the skin was obtained and then the DMSO diffusion coefficient with the passive diffusion model was calculated. Results show that it has a significant difference at different depths of the skin. Also, the DMSO concentration with the depth at different times was obtained and the same method was used to find the change law of the DMSO diffusion coefficient. Results indicate that it also changes with the treatment time. The experimental results are consistent with the theoretical model in a previous study. The current results demonstrate that Raman spectroscopy has the ability to quantitatively monitor the process of optical clearing. [ABSTRACT FROM AUTHOR]

A hybrid multilayer, composed of ten period amorphous AlAs/crystalline GaAlAs stacks, is realized by metalorganic chemical vapor deposition method on a GaAs substrate. Cross-sectional transmission electron microscopy shows the presence of sharp amorphous/crystalline interfaces. The electron diffraction patterns reveal the coexistence of both amorphous and crystalline phases and the perfect coherence of atom arrows between substrate and crystalline AlGaAs layers was also demonstrated. Perfect crystalline AlGaAs quality was further confirmed by x-ray rocking curves. The potential application of such hybrid multilayers is discussed and its behavior as a Bragg reflector is explored with a stop band gap of 75% reflectance. [ABSTRACT FROM AUTHOR]

Healthy foods are foods that have additional health benefits when compared with ordinary foods. In recent years, with the vigorous development of the healthy food industry, healthy foods have gradually entered the public eye and become a hot spot. Natural products are a class of bioactive compounds that play an important role in healthy foods, and the processing is a vital part of the development of the healthy food industry. The development of healthy foods is inseparable from the ever-changing food processing technology. Based on this, this article summarizes the high-tech processing technologies for healthy foods, comprehensively compares and analyzes the high and new technologies applied in the processing steps such as natural product production, active ingredient protection, component modification, preservation, sterilization, and product design, and provides an outlook on the future development of healthy foods by using high and new technologies.

Previous studies have demonstrated the ultrasound-induced skin optical clearing enhancement with topical application of 60 glycerol (G) on in vitroporcine skin and in vivohuman skin. Our purpose was to find the relation between the effect of optical skin clearing and different concentrations of glycerol and to find more effective ultrasound-glycerol combinations on optical skin clearing. The enhancement effect of ultrasound Sonophoresis (SP) delivery in combination with 40 G, 60 G, and 80 G on in vitrohuman skin optical clearing was investigated. Light imaging depths of skin were measured using optical coherence tomography. Different concentrations of glycerol and ultrasound with a frequency of 1 MHzand an intensity of 0.5 Wcm2was simultaneously applied for 15 min. The results show that with the increase of concentration of glycerol, the optical clearing of skin is much improved. Optical clearing capability of glycerol was more enhanced with simultaneous application of ultrasound compared with glycerol alone. The attenuation coefficients of skin tissues after application of 40 G/SP, 60 G/SP, and 80 G/SP decreased approximately 11.8, 18.5, and 20.0 at 15 mincompared with 40 G, 60 G, and 80 G alone, respectively. The greatest decrease in attenuation coefficients at 60 minwas approximately 52.3 and 63.4 for 80 G (without ultrasound) and 80 G/SP (with ultrasound), respectively, which are 2.1-fold and 2.6-fold to that in the 40 G. [ABSTRACT FROM AUTHOR]

Noninvasive tumor imaging could lead to the early detection and timely treatment of cancer. Optical coherence tomography (OCT) has been reported as an ideal diagnostic tool for distinguishing tumor tissues from normal tissues based on structural imaging. In this study, the capability of OCT for functional imaging of normal and tumor tissues based on time- and depth-resolved quantification of the permeability of biomolecules through these tissues is investigated. The orthotopic graft model of gastric cancer in nude mice is used, normal and tumor tissues from the gastric wall are imaged, and a diffusion of 20 aqueous solution of glucose in normal stomach tissues and gastric tumor tissues is monitored and quantified as a function of time and tissue depth by an OCT system. Our results show that the permeability coefficient is (0.94±0.04)×10−5 cmsin stomach tissues and (5.32±0.17)×10−5 cmsin tumor tissues, respectively, and that tumor tissues have a higher permeability coefficient compared to normal tissues in optical coherence tomographic images. From the results, it is found that the accurate and sensitive assessment of the permeability coefficients of normal and tumor tissues offers an effective OCT image method for detection of tumor tissues and clinical diagnosis. [ABSTRACT FROM AUTHOR]

Tongue inspection (TI) is an important and unique diagnostic method in traditional Chinese medicine (TCM), because significant connections between various viscerae diseases and abnormalities in the tongue have been verified. In TCM, TI is simple and non invasive, but in clinical applications, TI is subjectively based on the experience and technique of physicians. To avoid this problem, optical coherence tomography (OCT) imaging is introduced here for TI. We study OCT imaging in rats in vivo from chronic gastritis group (model) and normal group (control) and quantitatively analyze the relative parameters, such as the thickness and the moisture degree of TI. Our results show that OCT images properly demonstrate the thickness of the tongue coating and the moisture degree of the tongue in both groups, and the thickness is increased in the model group from that in the normal group, while the moisture degree decreases. As a result, OCT technology has the potential to provide physicians with an objective diagnostic standard for visual TI in TCM clinical practice and research. [ABSTRACT FROM AUTHOR]

A novel full-duplex radio-over-fiber system is proposed and demonstrated, in which an external modulator and an optical interleaver are used to generate dual octupling-frequency optical millimeter waves for two base stations and wavelength reuse for uplink connection. This scheme is simplified and low-cost because no additional laser is utilized for uplink connection at two base stations and one laser at central office works for two base stations simultaneously. The frequency of local oscillator signal is reduced largely due to frequency octupling. The theorem about how to generate optical millimeter waves is analyzed. The simulation results show that the bidirectional 5Gb/s system has a perfect performance because the power penalty for the downlink and uplink signals of two base stations are less than 0.6dB after successful transmission over 60km standard single mode fiber. [ABSTRACT FROM AUTHOR]

Nanographene oxide (NGO) with a non-sheddable poly(ethylene glycol) (PEG) coating has been used for chemo-photothermal therapy. However, the drug release of PEGylated NGO (NGO-PEG) with an amine bond is adversely affected by the diffusion barrier effect of PEG shells. Here, we developed a simple new method for the preparation of biodegradable PEGylated NGO conjugates (NGO-SS-PEG) with cleavable disulfide bonds for rapid drug release and more efficiently chemo-photothermal therapy. The glutathione (GSH)-induced and photothermal-mediated intracellular release of doxorubicin (DOX) from NGO-SS-PEG was studied in A549 cells using confocal laser scanning microscopy and flow cytometry analysis. In vivo cytotoxicity experiments were performed on chemo-photothermal therapy. Furthermore, we presented a comparative study of intracellular drug release and biological efficacy between NGO-SS-PEG/DOX and NGO-PEG/DOX. The results demonstrated that the rapid drug release from the NGO-SS-PEG conjugates with sheddable PEG was triggered upon the stimulus of high GSH levels inside A549 cells. Interesting, the DOX release mediated by the photothermal effect from the NGO-SS-PEG conjugates was found to be more obvious than that for NGO-PEG. Additionally, NGO-SS-PEG showed a higher efficacy than NGO-PEG for anti-tumor therapy compared with NGO-PEG. Thus, NGO-SS-PEG can improve therapeutic efficacy and is an attractive drug nanocarrier. [ABSTRACT FROM AUTHOR]