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Abstract Acetone is a widely used volatile organic compound in various industries, and several gas sensors have been developed for its detection and real-time monitoring. This study reported a novel method for determining the acetone vapor concentration based on correlated laser speckles using polymer-dispersed liquid crystals (PDLCs). Here, PDLC films comprising a mixture of the thermotropic nematic liquid crystal (LC) and ultraviolet-curable polymers were fabricated using different LC mass ratios and ultraviolet curing conditions. The laser beam was transmitted through the PDLC film to generate scattered light and speckles. When the PDLC film was exposed to the acetone vapor, the acetone molecules diffused into the PDLC film and interacted with the LC molecules, modifying the orientation of the LC molecules and the equivalent refractive index of the LC droplets. This in turn decreased the correlation coefficient of the speckle images. The experimental results indicated that the PDLC gas sensor was selectively sensitive to different concentrations of the acetone vapor, ranging from 1 800 ppm to 3 200 ppm. In comparison with traditional LC gas sensors that use a polarizing microscope to detect the change in brightness of the modulated light field, the proposed method is simpler, less expensive, and more robust under external disturbances such as vibrations.

Achieving a high sensitivity for practical applications has always been one of the main developmental directions for wearable flexible pressure sensors. This paper introduces a laser speckle grayscale lithography system and a novel method for fabricating random conical array microstructures using grainy laser speckle patterns. Its feasibility is attributed to the autocorrelation function of the laser speckle intensity, which adheres to a first-order Bessel function of the first kind. Through objective speckle size and exposure dose manipulations, we developed a microstructured photoresist with various micromorphologies. These microstructures were used to form polydimethylsiloxane microstructured electrodes that were used in flexible capacitive pressure sensors. These sensors exhibited an ultra-high sensitivity: 19.76 kPa−1 for the low-pressure range of 0–100 Pa. Their minimum detection threshold was 1.9 Pa, and they maintained stability and resilience over 10,000 test cycles. These sensors proved to be adept at capturing physiological signals and providing tactile feedback, thereby emphasizing their practical value.

Grayscale lithography (GSL) is an alternative approach to the standard binary lithography in MEMS fabrication, enabling the fabrication of complicated, arbitrary 3D structures on a wafer without the need for multiple masks and exposure steps. Despite its advantages, GSL’s effectiveness is highly dependent on controlled lab conditions, equipment consistency, and finely tuned photoresist (PR) exposure and etching processes. This works presents a thorough investigation of the challenges of GSL for silicon (Si) wafers and presents a detailed approach on how to minimize fabrication inaccuracies, aiming to replicate the intended design as closely as possible. Utilizing a maskless laser writer, all aspects of the GSL are analyzed, from photoresist exposure parameters to Si etching conditions. A practical application of GSL is demonstrated in the fabrication of 4-μm-deep f#/1 Si Fresnel lenses for long-wave infrared (LWIR) imaging (8–12 μm). The surface topography of a Fresnel lens is a good case to apply GSL, as it has varying shapes and size features that need to be preserved. The final fabricated lens profiles show a good match with the initial design, and demonstrate successful etching of coarse and fine features, and demonstrative images taken with an LWIR camera.

Glutathione (GSH) is an important biological thiol in cells, which is involved in many physiological processes in the organism and regulates pathological processes of cells. Rapid and accurate monitoring of GSH in vitro and in vivo is quite needed in investigating important biochemical events. In this contribution, innovative cerium (Ce) doped polyaniline (Ce–Fe@PANI NPs) were prepared via Fe(III) induced oxidization polymerization method. Upon addition of GSH, the absorption of Ce–Fe@PANI NPs red shifted from the visible to the NIR region, confirming the excellent absorption response to GSH. Moreover, Ce–Fe@PANI NPs exhibited excellent photoacoustic (PA) imaging enhancement in tube and shifted the PA intensity peak from 680 nm to 820 nm upon addition of GSH. In vitro and in vivo experiment verified that Ce–Fe@PANI NPs can monitor GSH in deep tissues via PA imaging technology. Collectively, this research provides Ce–Fe@PANI NPs would serve as a powerful nanoplatform to realize PA imaging detection of GSH in vitro and in vivo.

Nano-electrochemical materials and devices are at the frontier of research and development, advancing electrochemistry and its applications in energy storage, sensing, electrochemical processing, etc [...]

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Abstract Background Patients with locally advanced esophageal cancer with a lesion length greater than 8 cm (LCWEC) are prone to high mortality in a short time due to esophagotracheal fistula (ETF) and esophagoaortic fistula (EAF). We tried to explore a safe salvage surgical method during the perioperative period to maximize the resection of the tumor on the premise of safety and reconstruction of the alimentary tract to avoid early death due to ETF and EAF. Methods From December 2007 to November 2018, forty-five LCWEC patients were treated using the modified Wu’s esophagectomy. Patient features, surgical techniques, postoperative complications, and pathology outcomes were analyzed. Results The average length of the tumors was 12.5 cm (range 8.1–22.5 cm), and the average transverse tumor diameter was 5.8 cm (range 4.5–7.8 cm). No complications like anastomotic leakage, anastomotic stenosis, chylothorax, delayed gastric emptying, vocal cord paralysis, dumping syndrome, and reflux were detected. The 30-day and in-hospital mortality rates were 0%. Complete (R0) resection was achieved in 38 (84.4%) cases. The resection margin rate of positive anastomosis was 0%. Until the death of the patients, no feeding failure due to gastrointestinal obstruction and early death due to ETF or EAF occurrence. During follow-up, the median time to death was 17.2 months for patients treated with surgery alone and 32 months for patients treated with postoperative multimodal treatment. Conclusion The modified Wu’s esophagectomy is a safe and feasible salvage surgical method for LCWEC resection.

Abstract Objective Esophageal carcinoma (ESCA) is deadly cancer worldwide with unknown etiology. This study aimed to investigate the impact and mechanism of RAD6 on the development of Esophageal squamous cell carcinoma (ESCC). Expressions of RAD6A and RAD6B in ESCA were investigated from TCGA dataset and their expressions in tissue sample of ESCA patients and cells were determined. Functional experiments were conducted to explore the impact of RAD6A and RAD6B on malignant characteristics of several kinds of ESCC cells. Animal experiment was established and injected with RAD6A and RAD6B shRNA to evaluate the effect on tumor growth. RAD6A and RAD6B were up-regulated in ESCC cells and tissues. Overexpressed RAD6A and RAD6B similarly increased ESCC cell proliferation, invasion and migration and silencing of RAD6 exerted opposite effects. Knockdown of RAD6A suppressed tumor growth and decreased the level of H2B, as data demonstrated positive correlation between RAD6A and CCNB1 in ESCC tissues. Collectively, this study elucidates that RAD6 is up-regulated in ESCC and promotes the progression of ESCC through up-regulation of CCNB1 to enhance H2B ubiquitination. These evidence provide a novel insight into the pathogenesis of ESCC and might contribute to the development of targeted therapy.

Esophageal carcinoma (ESCA) affects 4 450 000 people and causes approximately 400 000 deaths annually worldwide, making it the sixth most lethal and eighth most common cancer. Patients with ESCA are often diagnosed at the later stages in which cancer cell metastasis is the main factor contributing to the low 5‐year survival rate ( 200 nucleotides but which fail to encode proteins. In this study, by using real‐time quantitative PCR, we found that the expression of the miR205 host gene (miR205HG; a lncRNA) was downregulated in ESCA tumors when compared with normal esophageal tissues or adjacent normal tissues of tumors. Furthermore, we demonstrated that miR205HG modulates the expression of extracellular matrix‐related genes in ESCA cells. In the transwell assay, downregulation of miR205HG contributes to migration and invasion of ESCA cells. In relation to the mechanism, our data show that miR205HG interacts with heterogeneous nuclear ribonucleoprotein A0 (HNRNPA0) mRNA and then hamper its translation by interacting with lin‐28 homolog A (LIN28A). Altogether, we highlight that the miR205HG‐HNRNPA0 axis is implicated in the migration and invasion of ESCA cells and that these members of this pathway may serve as therapeutic targets to inhibit metastasis of ESCA.

Traditional metal oxide semiconductor (MOS) gas sensors have limited applications in wearable devices owing to their inflexibility and high-power consumption by substantial heat loss. To overcome these limitations, we prepared doped Si/SiO2 flexible fibers by a thermal drawing method as substrates to fabricate MOS gas sensors. A methane (CH4) gas sensor was demonstrated by subsequently in situ synthesizing Co-doped ZnO nanorods on the fiber surface. The doped Si core acted as the heating source through Joule heating, which conducted heat to the sensing material with reduced heat loss; the SiO2 cladding was an insulating substrate. The gas sensor was integrated into a miner cloth as a wearable device, and the concentration change of CH4 was monitored in real time through different colored light-emitting diodes. Our study demonstrated the feasibility of using doped Si/SiO2 fibers as the substrates to fabricate wearable MOS gas sensors, where the sensors have substantial advantages over tradition sensors in flexibility, heat utilization, etc.

The integration of trivalent europium ion (Eu3+)-doped zinc molybdate (ZnMoO4) as red phosphors in next-generation solid-state lighting (SSL) is impeded by their extended electron lifetime and suboptimal thermal stability. To overcome these limitations, we propose a co-doping approach by incorporating Mn2+ and Eu3+ in ZnMoO4, aiming to improve thermal reversibility and reduce the lifetime of electron transitions. A series of Eu3+-doped ZnMoO4 and Mn2+/Eu3+-co-doped ZnMoO4 phosphor materials were synthesized via the conventional sol–gel method, and their photoluminescence properties were compared under high-temperature conditions. Experimental results indicate that the introduction of Mn2+ into Eu3+-doped ZnMoO4 leads to a decrease in quantum efficiency and electron lifetime, primarily attributed to defects within the crystal lattice and energy transfer from Eu3+ to Mn2+, resulting in enhanced non-radiative transitions. However, the addition of a small quantity of Mn2+ remarkably improves the thermal stability and reversibility of the phosphors. Consequently, this co-doping strategy presents a promising avenue for expanding the application possibilities of phosphor materials, particularly for high-power SSL applications subjected to elevated temperatures. Hence, Eu3+-only doped samples are well-suited for lighting applications due to their high IQE and excellent thermal stability. Conversely, Eu3+/Mn2+-co-doped samples show promise in applications that require a shorter electron lifetime and good reversibility.

In this study, a series of trivalent europium-doped tungstate and molybdate samples were synthesized using an improved sol-gel and high-temperature solid-state reaction method. The samples had different W/Mo ratios and were calcined at various temperatures ranging from 800 to 1000 °C. The effects of these variables on the crystal structure and photoluminescence characteristics of the samples were investigated. It was found that a doping concentration of 50% for europium yielded the best quantum efficiency based on previous research. The crystal structures were found to be dependent on the W/Mo ratio and calcination temperature. Samples with x ≤ 0.5 had a monoclinic lattice structure that did not change with calcination temperature. Samples with x > 0.75 had a tetragonal structure that remained unchanged with calcination temperature. However, samples with x = 0.75 had their crystal structure solely dependent on the calcination temperature. At 800–900 °C, the crystal structure was tetragonal, while at 1000 °C, it was monoclinic. Photoluminescence behavior was found to correlate with crystal structure and grain size. The tetragonal structure had significantly higher internal quantum efficiency than the monoclinic structure, and smaller grain size had higher internal quantum efficiency than larger grain size. External quantum efficiency initially increased with increasing grain size and then decreased. The highest external quantum efficiency was observed at a calcination temperature of 900 °C. These findings provide insight into the factors affecting the crystal structure and photoluminescence behavior in trivalent europium-doped tungstate and molybdate systems.

The purpose of the study is to improve the utilization rate of time sequence data generated by the Internet of Things (IoT), and explore their hidden values. Based on the deep neural network of Long Short-Term Memory (LSTM), the prediction model of multi-feature fusion time sequence data under Virtual Reality (VR) is discussed. First, the application of VR in various fields and the application status of a deep learning algorithm to IoT are analyzed. Second, the preprocessing method of time sequence data of IoT and the demand of deep learning neural networks in predicting time sequence data are analyzed. Based on the above analysis, the prediction model for multi-feature fusion time sequence data of IoT based on the deep learning network of LSTM is proposed. Finally, the experiment are designed to test the performance of the model. The results show that the proposed model and the LSTM-based regression model show high accuracy in the prediction of electrcity consumption data, while the Multi-Layer Perceptron (MLP) regression model has many errors in the prediction of the data. The mean absolute percentage error (Mape) of the proposed model is the lowest, with a percentage of only 2.49%, indicating that the difference between the predicted value and the real value of the proposed model is the smallest. The Mape of the LSTM regression prediction model is 2.57%, only slightly higher than the recommended model. The Mape of the MLP regression model is much higher, with a difference of 9% compared with the real value. The R2 of the model is 0.873, which is the highest. This study provides a reference for the application of deep learning neural networks in IoT.

Cobalt oxide (CoOx) nanowires have been broadly explored as advanced pseudocapacitive materials owing to their impressive theoretical gravimetric capacity. However, the traditional method of compositing with conductive nanoparticles to improve their poor conductivity will unpredictably lead to a decrease in actual capacity. The amelioration of the aspect ratio of the CoOx nanowires may affect the pathway of electron conduction and ion diffusion, thereby improving the electrochemical performances. Here, CoOx nanowires with various aspect ratios were synthesized by controlling hydrothermal temperature, and the CoOx electrodes achieve a high gravimetric specific capacity (1424.8 C g−1) and rate performance (38% retention at 100 A g−1 compared to 1 A g−1). Hybrid supercapacitors (HSCs) based on activated carbon anode reach an exceptional specific energy of 61.8 Wh kg−1 and excellent cyclic performance (92.72% retention, 5000 cycles at 5 A g−1). The CoOx nanowires exhibit great promise as a favorable cathode material in the field of high-performance supercapacitors (SCs).

Many practical applications require flexible high-sensitivity pressure sensors. However, such sensors are difficult to achieve using conventional materials. Engineering the morphology of the electrodes and the topography of the dielectrics has been demonstrated to be effective in boosting the sensing performance of capacitive pressure sensors. In this study, a flexible capacitive pressure sensor with high sensitivity was fabricated by using three-dimensional vertical graphene (VG) as the electrode and micro-pyramidal polydimethylsiloxane (PDMS) as the dielectric layer. The engineering of the VG morphology, size, and interval of the micro-pyramids in the PDMS dielectric layer significantly boosted the sensor sensitivity. As a result, the sensors demonstrated an exceptional sensitivity of up to 6.04 kPa−1 in the pressure range of 0–1 kPa, and 0.69 kPa−1 under 1–10 kPa. Finite element analysis revealed that the micro-pyramid structure in the dielectric layer generated a significant deformation effect under pressure, thereby ameliorating the sensing properties. Finally, the sensor was used to monitor finger joint movement, knee motion, facial expression, and pressure distribution. The results indicate that the sensor exhibits great potential in various applications, including human motion detection and human-machine interaction.

In this study, we developed a technology for broadening the 465 nm and 535 nm excitation peaks of Eu3+:Y2(MoO4)3 via crystal lattice orderly arrangement. This was achieved by powder particle aggregation and diffusion at a high temperature to form a ceramic structure. The powdered Eu3+:Y2(MoO4)3 was synthesized using the combination of a sol–gel process and the high-temperature solid-state reaction method, and it then became ceramic via a sintering process. Compared with the Eu3+:Y2(MoO4)3 powder, the full width at half maximum (FWHM) of the excitation peak of the ceramic was broadened by two- to three-fold. In addition, the absorption efficiency of the ceramic was increased from 15% to 70%, while the internal quantum efficiency reduced slightly from 95% to 90%, and the external quantum efficiency was enhanced from 20% to 61%. More interestingly, the Eu3+:Y2(MoO4)3 ceramic material showed little thermal quenching below a temperature of 473 K, making it useful for high-lumen output operating at a high temperature.

A non-enzymatic electrochemical sensor, based on the electrode of a chitosan-derived carbon foam, has been successfully developed for the detection of glutamate. Attributed to the chelation of Cu ions and glutamate molecules, the glutamate could be detected in an amperometric way by means of the redox reactions of chelation compounds, which outperform the traditional enzymatic sensors. Moreover, due to the large electroactive surface area and effective electron transportation of the porous carbon foam, a remarkable electrochemical sensitivity up to 1.9 × 104 μA/mM∙cm2 and a broad-spectrum detection range from nM to mM scale have been achieved, which is two-orders of magnitude higher and one magnitude broader than the best reported values thus far. Furthermore, our reported glutamate detection system also demonstrates a desirable anti-interference ability as well as a durable stability. The experimental revelations show that the Cu ions chelation-assisted electrochemical sensor with carbon foam electrode has significant potential for an easy fabricating, enzyme-free, broad-spectrum, sensitive, anti-interfering, and stable glutamate-sensing platform.

We study laser speckle reduction by light pipes, and we propose a new method to improve its efficiency. Proof-of-concept refractive optical elements (ROEs) with a staircase-like structure are introduced before a holographic diffuser to split a laser beam into laser sub-beams. Optical paths of the laser sub-beams after transmitting through the ROEs are different, and these partially correlated (or uncorrelated) laser sub-beams are added in intensity basis because of the folded mirror reflections by the light pipe. Thus, laser spatial coherence is suppressed, which helps to reduce speckle. We demonstrate this method in a simplified laser projection system, where subjective speckle contrast is reduced from 0.33 to 0.24 before and after introducing a two-dimensional ROE, respectively. Comparing with other improved speckle reduction methods by light pipes, the proposed method is motionless and simpler.

Recently, graphene-based materials have been successfully fabricated by the electrophoretic deposition (EPD) technique and exhibited various extraordinary properties. Here, research progress of the field of graphene-based materials prepared by the EPD process in recent 5 years is reviewed, including graphene films, graphene/non-metal composites, graphene/metal-based nanoparticles composites, graphene/polymer composites. We also summarize the experimental deposition conditions and the applications of the deposited graphene-based materials that have been reported. It can be concluded that EPD is a simple and reliable manipulation technique and promises a bright future for the production of graphene-based materials in the field of advanced nanocomposite materials. Finally the current issues and outlook of the development direction of EPD in future are also proposed. Keywords: Electrophoretic deposition, Graphene, Graphene-based composite materials, Applications

Abstract Background Mismatch‐repair genes (MMRs) ensure high fidelity in genome editing. Loss of function mutation of MMRs will lead to instability of the genome and increase the incidence of cancers. Human mutL homolog 1 (MLH1) is a member of the MMRs, and its mutation is found in Lynch syndrome (LS). In addition to the high incidence of colorectal cancer, LS patients often have other primary cancers. Here, a case of LS‐associated lung and gastric double primary cancer was reported. Methods Diagnosis of lung and gastric double primary cancer was mainly based on clinical findings, imaging examination, and histopathological data. The tumor tissues and blood samples were collected, and then genomic DNA was extracted and 450 cancer‐related gene alteration screening was conducted by next‐generation sequencing and the functional verification of a mutant gene was carried out using the PCR method. Results We detected the epidermal growth factor receptor L858R, MSH2 R929* and telomerase reverse transcriptase amplification in the lung cancer specimen; CDH1 c.1320+1G>T mutation in the gastric cancer (GC) specimen; and MLH1 c.1896+5G>A germline mutation in the lung and GC specimens by 450 cancer‐related gene mutations detection using next‐generation sequencing technology. MLH1c.1896+5G>A is a novel germline mutation, and it was verified by the PCR subsequently. It was found that it could affect the splicing of intron 16. Nine relatives of three‐generation of the patient were examined and the MLH1 c.1896+5G>A mutation and pedigree analysis were performed. The father's sister without cancer also carries this mutation. Conclusion Diagnosis of LS was mainly depended on the following: the cancer histories of his relatives, multi‐primary cancers of lung and stomach in his own body, MLH1 and MSH2 gene mutations detected in the cancer tissues. The clinical significance of this new MLH1 c.1896+5G>A germline mutation detected in the LS‐associated double primary cancer patient needed further study.

Sequential speckle reduction methods demand the usage of fast modulators due to the short integration period of human eyes. Here, a nonsequential speckle reduction method by splitting one laser beam with short coherence length into uncorrelated laser subbeams (LSBs) is reported. In order to realize the most efficient speckle reduction, with the help of a polarization beam splitter, we have programmed a reflective spatial light modulator to make the LSBs intensities equivalent. Three uncorrelated LSBs with equivalent light intensity are designed to demonstrate this idea; the speckle contrast ratio is reduced to 0.55, which closes to the expected value of 0.58. This nonsequential speckle reduction method has no requirement of the modulators speed; thus, it has obvious merit comparing with the sequential speckle reduction methods.

Ni-Co binary hydroxide grown on nickel foam was synthesized through a facile one-step process for pseudocapacitive electrode application. The morphology of the fabricated binary hydroxide, evolving from nanosheet to nanowire, was highly controllable by tuning the Ni:Co ratio. In systematical electrochemical measurements, the prepared binary material on nickel foam could be employed as a binder-free working electrode directly. The optimal composition obtained at the Ni:Co ratio of 5:5 in integrated nanosheet/nanowire geometry exhibited high specific capacitances of 2807 and 2222 F/g at current densities of 1 and 20 A/g, equivalent to excellent rate capability. The capacitance loss was 19.8% after 2000 cycles, demonstrating good long-term cyclic stability. The outstanding supercapacitors behaviors benefited from unique structure and synergistic contributions, indicating the great potential of the obtained binary hydroxide electrode for high-performance energy storage devices.

Hollow Co3O4 nanoboxes constructed by numerous nanoparticles were prepared by using a facile method consisting of precipitation, solvothermal and annealing reactions. The desirable hollow structure as well as a highly porous morphology led to synergistically determined and enhanced supercapacitor performances. In particular, the hollow Co3O4 nanoboxes were comprehensively investigated to achieve further optimization by tuning the sizes of the nanoboxes, which were well controlled by initial precipitation reaction. The systematical electrochemical measurements show that the optimized Co3O4 electrode delivers large specific capacitances of 1832.7 and 1324.5 F/g at current densities of 1 and 20 A/g, and only 14.1% capacitance decay after 5000 cycles. The tunable synthesis paves a new pathway to get the utmost out of Co3O4 with a hollow architecture for supercapacitors application.

In this study, a zeolitic imidazolate framework-67 (ZIF-67) was prepared as a precursor using a facile hydrothermal method. After a calcination reaction in the air, the as-prepared precursor was converted to porous thin-wall hollow Co3O4 with its original frame structure almost preserved. The physical and chemical characterizations of the nanomaterial were analyzed systemically. The electrochemical tests indicate that the obtained Co3O4 possesses large specific capacitances of 988 and 925 F/g at 1 and 20 A/g accompanying an outstanding rate capability (a 93.6% capacitance retention) and retains 96.6% of the specific capacitance, even after 6000 continuous charge/discharge cycles. These excellent properties mark the Co3O4 a promising electrode material for high performance supercapacitors.

Digital competence development in basic education is essential. The main purpose of this study was to measure the levels of digital competencies among students in four areas using a digital competency questionnaire to improve the effectiveness of digital management in basic education. The authors used the digital competence questionnaire for students as a measurement tool, which was subjected to validation. The respondents were 323 students aged 8-14 from three schools in the People's Republic of China. The PLS-SEM-based CFA approach revealed the validity of the questionnaire, which resulted in high data reliability and consistency. Statistical analysis revealed no significant differences with gender and significant correlations (p < 0.05) with age. The students aged 13-14 scored the highest on the domains, while the youngest team aged 8-10 scored the lowest. This article is of practical value as it provides a verified tool for checking the digital competence levels of Chinese students. According to the results, it is crucial to incorporate the development of digital competencies into the elementary school settings to facilitate learning and provide children with an opportunity to achieve a higher digital competence in the future.

Designs and simulations of silicon-based micro-electromechanical systems (MEMS) infrared (IR) thermal emitters for gas sensing application are presented. The IR thermal emitter is designed as a bridge-style hotplate (BSH) structure suspended on a silicon frame for realizing a good thermal isolation between hotplate and frame. For investigating the reliability of BSH structure, three kinds of fillet structures were designed in the contact corner between hotplate and frame. A 3-dimensional finite element method (3D-FEM) is used to investigate the electro-thermal, thermal-mechanical, and thermal-optical properties of BSH IR emitter using software COMSOLTM (COMSOL 4.3b, COMSOL Inc., Stockholm, Sweden). The simulation results show that the BSH with oval fillet has the lowest stress distribution and smoothest flows of stress streamlines, while the BSH with square fillet has the highest temperature and stress distribution. The thermal-optical and thermal-response simulations further indicate that the BSH with oval fillet is the optimal design for a reliable IR thermal emitter in spite of having slight inadequacies in emission intensity and modulation bandwidth in comparison with other two structures.