Thermal and electrical switchable wide-angle multi-band terahertz absorber.

Multi-band terahertz (THz) absorbers have recently gained attention due to their favorable application prospects in communication, imaging, detection, and other fields. However, many multi-band THz absorbers are tuned by a single method, which limits their tuning effect. To address this issue, we propose a multi-band THz absorber that can be co-modulated by thermal and electrical methods. Our proposed absorber uses vanadium dioxide (VO2) to achieve this co-modulation. When VO2 is insulating, the frequency of the absorbing peaks originating from the lateral Fabry-Pérot resonance mode can be changed by adjusting the VO2 width. When VO2 is a conductor, the quality factor of the absorbing peak based on the inductor-capacitor resonance mode can be tuned by adjusting the width of VO2. By varying the top dielectric layer thickness, the frequency of the absorbing peaks can be tuned over a wide range. For devices with two or three layers of graphene nanoribbons-dielectric stacks, a modulation effect similar to that of varying dielectric layer thickness in a single-layer graphene device can be achieved simply by applying a 1 eV Fermi energy to graphene nanoribbons in different layers. By combining thermal and electrical modulation, the two or three-layer stacked device can be dynamically switched between four or six absorbing states, and a wider range of dynamic peak frequency modulation can be realized. Furthermore, the performance of the absorber does not deteriorate significantly at an incident angle of up to 70°. Our proposed thermal-electrical switchable wide-angle multi-band THz absorber provides a reference for the design, fabrication, and application of high-performance THz absorbers in different fields.

Construction and validation of a nomogram for predicting fear of falling related activity restrictions in community-dwelling older adults.

Fear of falling related activity restrictions are widespread among older adults, leading to several adverse effects. Given these consequences, there is an urgent need for a comprehensive assessment tool that integrates various risk factors to predict the likelihood of older adults experiencing such activity restrictions. This cross-sectional study investigated fear of falling related activity restrictions and its influencing factors, simultaneously constructed and validated a nomogram among older adults residing in the communities in China. The model includes variables like age, gender, self-rated health, past year injurious falls, gait stability, anxiety, and cognitive impairment. It showed an AUC of 0.892. Internal validation had an AUC of 0.893, and external validation had an AUC of 0.939. Calibration curve showed good fit, and decision curve showed high clinical benefits. It's an intuitive tool for medical professionals to identify older adults at high risk of activity restrictions due to fear of falling.

Tandem Addition/Cyclization/Halogenation Reaction of Difluoromethylated N-Acylhydrazones with Allyltrimethylsilanes.

As novel difluoromethyl building blocks, difluoromethylated N-acylhydrazones react with allyltrimethylsilanes and the halogen source via a tandem addition/cyclization/halogenation strategy, which produces various difluoromethylpyrazoline compounds in good yields. The method features mild reaction conditions, broad substrate scopes, and a transition metal-free process with easy operation. It also proves that difluoromethylated N-acylhydrazones are useful difluoromethyl building blocks for the construction of difluoromethylated nitrogen heterocycles.

Estimating the velocity of chemically-driven Janus colloids considering the anisotropic concentration field.

The application of the active colloids is strongly related to their self-propulsion velocity, which is controlled by the generated anisotropic concentration field. We investigated the effect of this anisotropy on velocity induced by numerical treatments and size of Janus colloids. The far-field approximation is effective in estimating the velocity, even though it neglects the shape effect on the anisotropy of the concentration field. If the surface mobility contrast between the active and the inert part is moderate, the spherical approximation is feasible for sphere-like Janus colloids. Legendre expansion of the concentration field causes artificial anisotropy. Raising the order of the expansion can suppress this effect, but also distorts the concentration field at the top of active part. Thus, the order of the expansion should be chosen carefully depending on the goal of the study. Based on the verified Legendre expansion method and ionic-diffusiophoresis model, we show that due to the size-effect on both the concentration field and the surface mobility, increasing size of colloids can lower the self-propulsion velocity. Our finding is consistent with previous experimental observations without fitting parameter, shedding new light on the self-propulsion mechanism of chemically-driven active colloids. We further show a velocity reversal at high overall ζ potential induced by increasing size, providing a new way for controlling the dynamics of acitve colloids.

Independently tunable multi-band terahertz absorber based on graphene sheet and nanoribbons.

A multi-band terahertz (THz) absorber based on graphene sheet and nanoribbons is proposed and investigated. In the studied frequency range, five absorption peaks are observed, with four originate from lateral Fabry-Perot resonance (LFPR) and one originates from guided-mode resonance (GMR). The LFPR and GMR peaks behave differently when geometric parameters are adjusted, which makes independent tuning possible. When period increases, the GMR peak red shifts and the frequencies of LFPR peaks remain almost unchanged. On the contrary, as nanoribbon width increases, the frequency of GMR remains almost unchanged while that of LFPRs decrease significantly. With increasing top dielectric layer thickness, the LFPR peaks blue shift while the GMR peak red shifts. In addition, the absorber has the merit of multi-band high absorptivity and frequency stability under large angle oblique incidence. The proposed terahertz absorber may benefit the areas of medical imaging, sensing, non-destructive testing, THz communications and other applications.

MicroRNA­491­5p inhibits trophoblast cell migration and invasion through targeting matrix metalloproteinase­9 in preeclampsia.

Insufficient invasion of trophoblasts is correlated with the development of preeclampsia (PE). MicroRNA (miR)­491­5p has been reported to be implicated in human cancer cell invasion; however, whether miR­491­5p is involved in the development of PE remains largely unclear. The aim of the present study was to investigate the role of miR­491­5p in trophoblastic invasion in vitro and to determine its underlying mechanism of action. The expression levels of miR­491­5p were validated using reverse transcription­quantitative PCR. The effects of miR­491­5p on trophoblast cell invasion were evaluated in vitro. Then, the association between miR­491­5p and its downstream target was investigated in both cell lines and clinical specimens. miR­491­5p expression levels were observed to be significantly increased in the placental tissues from patients with PE. The invasive capacity of HTR­8/SVneo trophoblast cells was suppressed following the upregulation of miR­491­5p and increased following the inhibition of miR­491­5p. Matrix metalloproteinase­9 (MMP­9), a well­known regulator of trophoblast cell invasion, was discovered to be a direct target of miR­491­5p in HTR­8/SVneo trophoblast cells. Moreover, miR­491­5p expression levels were found to be inversely correlated with MMP­9 expression levels in placental tissues from patients with PE. The overexpression of MMP­9 partly attenuated the inhibitory effects of miR­491­5p on HTR­8/SVneo trophoblast cells invasion. Collectively, these findings suggested that the aberrant expression of miR­491­5p may contribute to PE through suppressing trophoblast invasion, thus highlighting the novel roles of miR­491­5p in the molecular pathogenesis of PE. The present study also showed that the miR­491­5p/MMP­9 axis may be an effective biomarker or a viable drug target for therapeutic intervention in PE.

Long-Chain Non-Coding RNA SNHG3 Promotes the Growth of Ovarian Cancer Cells by Targeting miR-339-5p/TRPC3 Axis.

BACKGROUND: Long-chain non-coding RNA (lncRNA) small nucleolar RNA host gene 3 (SNHG3) is reportedly overexpressed in malignant tumors, but its regulatory role in human ovarian cancer (OC) is not fully understood. METHODS: A qRT-PCR assay was carried out to detect the level of SNHG3 in OC tissues, serum and cells, a CCK-8 assay to measure the proliferation of OC cells, a transwell assay to measure the invasion and migration of OC cells, and a flow cytometry to detect the cell cycle distribution and apoptosis rate of OC cells. In addition, in vivo experiment was also conducted to determine the effect of SNHG3 on the growth of OC cells. RESULTS: SNHG3 was overexpressed in OC tissues, serum, and cells, and the overexpression in serum indicated a poor prognosis of patients. It was also found that knockdown of SNHG3 could inhibit the malignant phenotypes of OC cells, cause G1/G0 cell cycle arrest, and intensify apoptosis. Furthermore, in in vitro experiments, the growth ability of OC cells was inhibited under knockdown of SNHG3. Assays for relationship verification showed that SNHG3 regulated the expression of miR-339-5p and the canonical transient receptor potential 3 (TRPC3), and the rescue experiment revealed that co-transfection of si-SNHG3+miR-339-5p-inhibitor or si-SNHG3+pcDNA3.1-TRPC3 could reverse the effects of knockdown of SNHG3 on the biological behavior of OC cells. CONCLUSION: SNHG3 can be adopted as a marker for diagnosis and prognosis evaluation of OC and it plays a role in the progression of OC by enabling the miR-339-5p sponge to regulate TRPC3 expression.

Classification of multicategory edible fungi based on the infrared spectra of caps and stalks.

As a characteristic edible fungus with a high nutritional value and medicinal effect, the Bachu mushroom has a broad market. To distinguish among Bachu mushrooms with high value and other fungi effectively and accurately, as well as to explore a universal identification method, this study proposed a method to identify Bachu mushrooms by Fourier Transform Infrared Spectroscopy (FT-IR) combined with machine learning. In this experiment, two kinds of common edible mushrooms, Lentinus edodes and club fungi, were selected and classified with Bachu mushrooms. Due to the different distribution of nutrients in the caps and stalks, the caps and stalks were studied in this experiment. By comparing the average normalized infrared spectra of the caps and stalks of the three types of fungi, we found differences in their infrared spectra, indicating that the latter can be used to classify and identify the three types of fungi. We also used machine learning to process the spectral data. The overall steps of data processing are as follows: use partial least squares (PLS) to extract spectral features, select the appropriate characteristic number, use different classification algorithms for classification, and finally determine the best algorithm according to the classification results. Among them, the basis of selecting the characteristic number was the cumulative variance interpretation rate. To improve the reliability of the experimental results, this study also used the classification results to verify the feasibility. The classification algorithms used in this study were the support vector machine (SVM), backpropagation neural network (BPNN) and k-nearest neighbors (KNN) algorithm. The results showed that the three algorithms achieved good results in the multivariate classification of the caps and stalks data. Moreover, the cumulative variance explanation rate could be used to select the characteristic number. Finally, by comparing the classification results of the three algorithms, the classification effect of KNN was found to be the best. Additionally, the classification results were as follows: according to the caps data classification, the accuracy was 99.06%; according to the stalks data classification, the accuracy was 99.82%. This study showed that infrared spectroscopy combined with a machine learning algorithm has the potential to be applied to identify Bachu mushrooms and the cumulative variance explanation rate can be used to select the characteristic number. This method can also be used to identify other types of edible fungi and has a broad application prospect.

MicroRNA­142­3p inhibits trophoblast cell migration and invasion by disrupting the TGF­ß1/Smad3 signaling pathway.

Insufficient invasion of trophoblasts is known to be associated with preeclampsia (PE) development. Recently, microRNAs (miRNAs) have been reported to serve important roles in the pathogenesis of PE. However, little is known regarding the regulation of trophoblastic invasion by miRNAs. The aim of the present study was to explore the role of miRNAs in trophoblastic invasion and the underlying molecular mechanism. Using a miRNA microarray, miRNAs putatively involved in the pathophysiology of PE were examined between normal and preeclamptic placentas. Validation analysis of miR­142­3p level in placenta specimens was performed using reverse transcription­quantitative polymerase chain reaction (RT­qPCR). Then, the regulation of miR­142­3p on trophoblast cells migration and invasion was evaluated using wound healing and transwell migration assays. Furthermore, the target gene of miR­142­3p and the downstream signaling pathway were also investigated. Microarray analysis and RT­qPCR revealed that miR­142­3p was significantly upregulated in placenta specimens from patients with PE. Its overexpression inhibited trophoblast cell invasion and migration, whereas its knockdown enhanced trophoblast cell invasion and migration. In addition, overexpression of miR­142­3p inhibited the mRNA expression and the activities of matrix metalloproteinase­2 (MMP2) and MMP9, which are closely associated with cell invasion and migration, while inhibition of miR­142­3p had the opposite result. Subsequent analyses demonstrated that transforming growth factor­ß1 (TGF­ß1) was a direct and functional target of miR­142­3p. Notably, the knockdown of TGF­ß1 effectively reversed the enhancement of miR­142­3p inhibitor on trophoblast cell invasion and migration. Finally, the present study confirmed that miR­142­3p inhibitor enhanced cell invasion and migration by reactivating the TGF­ß1/Smad3 signaling pathway. Taken together, the results of the present study suggest that miR­142­3p may serve an important role in human placental development by suppressing trophoblast cell invasion and migration through disruption of the TGF­ß1/smad3 signaling pathway, suggesting that knockdown of miR­142­3p may provide a novel therapy for PE.

Prognosis in Pregnant Females With Systemic Lupus Erythematosus.

OBJECTIVES: This study aims to analyze the relationship between pregnancy and lupus, and explore the risk factors that adversely affect maternal and infant outcomes. PATIENTS AND METHODS: The pregnancy outcomes in 112 pregnant females (mean age 24.3±2.8 years; range 20 to 35 years) with systemic lupus erythematosus (SLE) were retrospectively analyzed. Pregnancy outcomes before and after pregnancy were compared, and the associations with lupus nephritis, positive anti-Ro/SSA antibody, positive La/SSB antibody, complement 3 and complement 4, high blood pressure, positive anti- cardiolipin (aCL) antibody, Raynaud's phenomenon, and lupus recurrence were evaluated. Factors contributing to adverse outcomes were analyzed using multinomial logistic regression. RESULTS: The live birth rate in females diagnosed with SLE before a pregnancy was higher than that in females diagnosed with SLE after a pregnancy. The fetal mortality rate in females diagnosed with SLE after a pregnancy was higher than that in females diagnosed with SLE before a pregnancy. However, the abortion rate in females diagnosed with SLE before a pregnancy was also significantly higher than that in females diagnosed with SLE after a pregnancy. The incidence of preterm birth in females diagnosed with SLE after a pregnancy was higher than that in females diagnosed with SLE after a pregnancy. Preterm birth was more likely to occur in females positive for Ro/SSA antibody. Patients with hypertension and Raynaud's phenomenon had a higher risk of intrauterine growth retardation. In addition, the presence of aCL antibody was associated with pregnancy loss. Multinomial logistic regression analysis showed that many factors might be associated with adverse pregnancy outcomes, including lupus nephritis, positive Ro/SSA antibody, positive La/SSB antibody, complement 3 and complement 4, positive aCL antibody, lupus recurrence, hypertension, and Raynaud's phenomenon. CONCLUSION: Lupus nephritis, Ro/SSA antibody, aCL antibody, hypertension, Raynaud's phenomenon, and lupus recurrence are important factors associated with adverse pregnancy outcomes.

Introduction and analysis of the latest changes in head and neck cancer staging / 中国肿瘤临床

The TNM staging system is an essential standard for cancer treatment and evaluation, and is used to assess a patient''s prog-nosis. Therefore, every update made to the system is of great significance. According to the recently released edition of the American Joint Committee on Cancer (AJCC) Staging Manual, several major changes to head and neck cancer staging have been made. In this pa-per, we analyze the advantages and disadvantages of these amendments and offer a direction for making future amendments. Our goal is to provide a brief introduction of recent research on head and neck cancers, which can be used as a reference by clinicians.

Controlling plasmon-induced transparency of graphene metamolecules with external magnetic field.

We numerically demonstrate dynamically tuneable plasmon-induced transparency in a π-shaped metamolecules made of graphene nanostrips by applying external static magnetic field. It is shown that for graphene nanostrips with appropriate Fermi energy, the resonant wavelength, line-shape, and the polarization of transmitted light in the mid-infrared can be effectively controlled by magnetic field. In particular, giant polarization rotation exceeding 20° has been observed in asymmetric graphene metamolecules, which is further enhanced to almost 40° due the Faraday effect in the applied magnetic field, at around 9 µm wavelength, much higher frequency than the Faraday rotation observed in a semi-infinite graphene microribbons. The results offer a flexible approach for the development of compact, tunable graphene-based photonic devices.

Carboplatin-docetaxel-induced activity against ovarian cancer is dependent on up-regulated lncRNA PVT1.

Ovarian cancer is the fourth most ordinary cause of cancer-related deaths in women. In recent, combination chemotherapy with carboplatin and docetaxel was developed as first-line drug to treat ovarian carcinoma. However, the detailed molecular mechanism, which accounts for the cells to apoptosis induced by administration of carboplatin and docetaxel, was unrecognized. In present study, we provide the mechanistic link between mixture of carboplatin plus docetaxel and its anticancer activity. Primarily, a majority of 30 cancer-related long non-coding RNA (lncRNA) showed differential alteration in carboplatin-docetaxel-treated 3AO cells. Among six up-regulating lncRNAs, we screened out carboplatin-docetaxel-induced lncRNA PVT1 which may be a central downstream target of carboplatin plus docetaxel because expression of PVT1 positively correlates with anticancer action of carboplatin plus docetaxel. Besides, p53 and tissue inhibitor of matrix metalloproteinases-1 (TIMP1) were mediated by lncRNA PVT1, which may explain partially the anticancer activity of lncRNA PVT1. Collectively, we have identified a potential mechanism by which PVT1 regulated by carboplatin plus docetaxel contributes to the carboplatin-docetaxel-induced anticancer action in ovarian cancer. These discoveries also give proof of the potential of PVT1 as significant downstream targets for therapeutic intervention in ovarian cancer.

Overexpression of long non-coding RNA PVT1 in ovarian cancer cells promotes cisplatin resistance by regulating apoptotic pathways.

Ovarian cancer is the most lethal gynecologic malignancy. Cisplatin is a very effective cancer chemotherapy drug, but cisplatin resistance is a crucial problem of therapy failure. Overexpression of PVT1 has been demonstrated in ovarian cancer. The mRNA level of PVT1 in ovarian cancer tissues of cisplatin-resistant patients and cisplatin-sensitive patients, cisplatin-resistant cells SKOV-3/DDP and A2780/DDP, cisplatin-sensitive cells SKOV-3 and A2780 were determined by qRT-PCR. The influence of the knockdown or overexpression of PVT1 on cisplatin resistance was measured by measuring the cytotoxicity of cisplatin and the apoptotic rate of ovarian cancer cells was detected by CCK-8 assay and flow cytometry, respectively. The mRNA levels and protein expression of TGF-ß1, Smad4, p-Smad4 and Caspase-3 in apoptotic pathways were determined. The mRNA level of PVT1 was significantly higher in ovarian cancer tissues of cisplatin-resistant patients and cisplatin-resistant cells. SKOV-3/DDP and A2780/DDP cell viability and the percentage of apoptotic cells after transfection with PVT-1 siRNA and treated with cisplatin was markedly lower and higher than the control, respectively. Moreover, the overexpression of PVT1 exhibited the anti-apoptotic property in SKOV-3 and A2780 cells after transfection with LV-PVT1-GFP and treated with cisplatin. The mRNA levels and protein expression of TGF-ß1, p-Smad4 and Caspase-3 were much higher in cisplatin-resistant cells transfected with siPVT1. Overexpression of LncRNA PVT1 in ovarian cancer promotes cisplatin resistance by regulating apoptotic pathways.

Fabrication and performance of contamination free individual single-walled carbon nanotube optical devices.

Contamination free individual single-walled carbon nanotube (SWCNT) optical devices are fabricated using a hybrid method in the purpose of increase sensitivity as well as further understanding the sensing mechanism. The devices were tested in vacuum to avoid contamination. Three typical devices are discussed comparatively. Under infrared lamp illumination, photovoltaic and photoconductive properties are revealed in device A and B respectively, while device C shows no detectable signal. The photoresponse of device B reaches 108% at 78 K, much larger than that of horizontally aligned or network carbon nanotube devices, indicating priority of the individual nanotube device structure. Interestingly, the temperature characteristics of device A and B are just the opposite. The individual SWCNT devices hold promise in high performance and low cost optical sensors as well as nano-scale solar cells.

The synthesis and fabrication of horizontally aligned single-walled carbon nanotubes suspended across wide trenches for infrared detecting application.

Horizontally aligned single-walled carbon nanotubes (SWNTs) were directly grown across trenches produced on SiO(2)/Si substrate, forming suspended aligned SWNTs over the trenches, and were fabricated with simple methods for infrared (IR) detection application. The horizontally aligned SWNTs can grow across trenches as wide as 40 microm. The detector based on such SWNTs shows sharp and remarkable responses to the ON/OFF state changes of the IR lamp and IR radiation with different frequencies. The resistance of the SWNTs decreases about 22.86% under IR radiation with power less than 4 mW. The detector photoresponse to IR radiation of 120 Hz at room temperature could be easily observed. The response time constant is only about 500 micros, which is more than two orders of magnitude shorter than that of the reported devices based on SWNT films and SWNT-polymer composites. This was achieved due to the absence of intertube junctions in our horizontally aligned SWNTs which exist in SWNT bundles and films and may reduce the signal conduction speed and the IR photoresponse performance. Instead of the bolometric model, the interband transition model is suggested to be the dominating origin of the photoresponse of our SWNT-based detector configuration.