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High-performance all-solid-state fiber supercapacitors assembled with MXene/RGO/PEDOT:PSS hybrid fiber electrodes with radially oriented channels and an anti-freezing electrolyte exhibit excellent capacitance retention at ultralow temperatures.

Particle Impact Drilling (PID) is a new technology to effectively improve the rate of penetration (ROP) for oil and gas drilling in hard and strongly abrasive formations. In this paper, numerical simulation method is used to analyse the motion characteristics and the modulation method of particle swarm in high-pressure tank for the particle injection system based on differential pressure ejection in PID. The numerical simulation results show that: when there is no modulation elements, the motion of particle swarm in the high-pressure tank follows an asymmetric funnel flow with pulsating state, which could be divided into vertical flow domain, fast flow domain, slow flow domain and stagnation domain. The unstable dynamic arching effect of the funnel flow, the viscous effect of the liquid bridge force and the collapsing effect of the particle swarm could probably lead to the blockage of the discharge port of the high-pressure tank. When the semiapex angles of the high-pressure tank decreases, the volume flow rate of particles increases and the stagnation domain becomes smaller, but it becomes easier to form arching and blockage. The modelling results indicate that the pulsation of the funnel flow is minimum when the semiapex angle is 45° without the mutilation element, which means the funnel flow of the particle swarm is relatively stable. By introducing a conical modulating element above the discharge port, the unstable funnel flow of the particle swarm could be transformed to an overall uniform flow. The modelling results indicate that the installation height of the modulation element has the greatest influence on the pulsation degree. The optimized parameters for the conical modulation element based on numerical modelling tests are 70° for the vertex angle, 35 mm for the length of the flank and 70 mm for the installation heigh.

A suitable jump Markov system (JMS) filtering approach provides an efficient technique for tracking surface targets. In complex surface target tracking situations, due to the joint influences of lost measurements with an unknown probability and heavy-tailed measurement noise (HTMN), the estimation accuracy of conventional interacting multiple model (IMM) methods may be seriously degraded. Aiming to address the filtering issues in JMSs with HTMNs and random measurement losses, this paper presents an IMM filtering approach with the adaptive estimation of unknown measurement loss probability. In this study, we assumed that the measurement noises obey student’s t-distributions and then proposed Bernoulli random variables (BRVs) to characterize the random measurement loss. Notably, by converting the two likelihood functions from the weighted sum form to exponential multiplication, we established hierarchical Gaussian state space models to directly utilize the variational inference method. The system state vectors, unknown distribution parameters, BRVs, and unknown measurement loss probabilities were estimated simultaneously according to the variational Bayesian inference in the IMM framework. The results of maneuvering target tracking simulations verified that the presented filtering approach demonstrated superior estimation accuracy compared to existing IMM filters.

In this work, MgAl-layered double hydroxides (LDH) were synthesized by co-precipitation method using a colloid mill and characterized by XRD and SEM. It was found that the environmentally friendly LDHs had greater performance than the traditional antioxidant. By adding LDHs into large electric shovel grease (GRK-A) in open-pit coal mine, the service lifetime of grease was extended by 20%. With the increase in LDH addition, the grease sample attains greater activation energy, and the thermal oxidation and decomposition resistance become stronger. Comparing the energy storage modulus and flow transition index at different temperatures, adding the right amount of LDHs needs close attention for the system oxidation resistance and viscoelasticity. For the electric shovel grease, the best oxidation resistance and rheological properties can be achieved by adding 2% of LDHs. The rheological viscosity–temperature curves show that the grease samples with different ratios of solid LDHs have better low-temperature properties than the mine grease. This work outlines a simple method for creating an environmentally sustainable lubricant additive with the use of LDH. LDH serves as a novel inorganic antioxidant additive that is optimal for open gear lubrication and sliding friction.

A proper filtering method for jump Markov system (JMS) is an effective approach for tracking a maneuvering target. Since the coexisting of heavy-tailed measurement noises (HTMNs) and one-step random measurement delay (OSRMD) in the complex scenarios of the surface maneuvering target tracking, the effectiveness of typical interacting multiple model (IMM) techniques may decline severely. To solve the state estimation problem in JMSs with HTMN and OSRMD simultaneously, this article designs a novel robust IMM filter utilizing the variational Bayesian (VB) inference framework. This algorithm models the HTMNs as student’s t-distribuitons, and presents a random Bernoulli variable to describe the OSRMD in JMSs. By transforming measurement likelihood function form from weighted summation to exponential product, this paper constructs hierarchical Gaussian state space models. Then, the state vectors, random Bernoulli vairable, and model probability are inferred jointly according to VB inference. The surface maneuvering target tracking simulation example result indicates that the presented IMM filter achieves superior target state estimation accuracy among existing IMM filters.

Background This study aimed to compare the clinical outcomes of non-transecting urethroplasty and lingual mucosal urethroplasty in the treatment of iatrogenic bulbar urethral stricture. Results A total of 25 patients with iatrogenic bulbar urethral stricture were enrolled, 12 of whom underwent lingual mucosal urethroplasty, 13 patients who underwent non-transecting urethroplasty. All patients were followed-up and evaluated at 3 postoperative months. Evaluations included urethrography, maximum urine flow rate (Qmax), nocturnal erectile function testing, International Index of Erectile Function (IIEF-5) assessment, and Anxiety Related Scale (SAS) assessment. In terms of operation time, there was a significant difference between non-transecting urethroplasty and lingual mucosal urethroplasty. However, there was no significant intergroup difference in intraoperative blood loss. Both techniques were associated with significantly improved Qmax relative to preoperative rates, but there was no significant difference between the groups in this regard over 3 months of postoperative follow-up. Nocturnal penile tumescence and rigidity results showed that there was no significant change in tip hardness after surgery in the non-transecting urethroplasty group. Moreover, IIEF-5 scores indicated that there was no significant intergroup difference in terms of subjective postoperative erectile function. According to the preliminary psychological evaluations during postoperative follow-up, the anxiety scores of patients undergoing non-transecting urethroplasty significantly improved, but there was no significant change in the mean SAS score among patients who underwent lingual mucosal urethroplasty. Conclusion Both surgical methods can achieve the clinical goal of treating iatrogenic bulbar urethral stricture. Non-transecting urethroplasty has the characteristics of short operation time, relative technical simplicity, and retention of the original erectile function of most patients, and the surgical outcomes of non-transecting urethroplasty are not inferior to those of lingual mucosal urethroplasty, and it is a promising technique for widespread use to treat bulbar urethral strictures.

In this paper, MgAl Layered double hydroxides (LDH) were synthesized by co-precipitation method using a colloid mill and characterized by XRD, IR and SEM. The LDHs was repeatedly tested and compared with different bearing lifetime tester in lithium base grease, and it was found that the environmental-friendly LDHs had greater performance than the traditional antioxidant, and it was the development direction of a new generation of environmental-friendly antioxidants in the future. By adding LDHs into large electric shovel greats (GRK-A) in open-pit coal mine, it can be seen by PDSC evaluation that the service lifetime of grease is extended by 20% while the overall performance of grease is not affected. With the increase of LDHs addition, the grease sample gets the greater activation energy, the stronger thermal oxidation and decomposition resistance. Comparing the energy storage modulus and flow transition index at different temperatures, it can be seen that adding the right amount of LDHs needs close attention for the system oxidation resistance and viscoelasticity. For the electric shovel grease system, the best oxidation resistance and rheological properties can be achieved by adding 2% of LDHs. The rheological viscosity-temperature curves show that the grease samples with different ratios of solid LDHs have better low-temperature properties than the mine grease.

The dispersion of nanomaterials in lubricating oil plays an important role in the lubrication and wear-resistance properties. In this work, supramolecular layered double hydroxides (LDHs) were prepared and added to lubricating oil with different dispersants. The content of key elements in the samples was measured by an oil element analyzer, and the dispersion properties of different samples were studied. The friction coefficient of the samples was measured by high-frequency linear vibration (SRV), and the morphology and composition were characterized by SEM to study the antiwear performance and action mechanism of LDH. The oxidation induction time of the samples was measured by RBOT to study the antioxygenic properties of LDH in lubricating oil. The results show that LDH can be well-dispersed in lubricating oil with the action of specific dispersants. After adding LDH, the antiwear performance of lubricating oil was improved, as a uniform and dense protective film was formed on the friction surface.

Hybrid models based on a generalized regression neural network (GRNN), adaptive least absolute shrinkage and selection operator (AdaLASSO), and sparse group LASSO (SGL) were used for quantitative analysis of arsenic (As) and chromium (Cr) in soil.

Due to the material properties of single-crystal silicon, it is difficult to achieve high-efficiency processing in conventional turning. Fast tool servo (FTS) turning has emerged as a favorable technology for processing brittle materials. This paper investigates the tool radius, feed speed, and cutting depth effects on the maximum undeformed chip thickness (MUCT). A high-frequency low-coupling FTS system is designed for processing experiments. Effects of the tool rake angle, tool radius, cutting speed, and vibration frequency on the critical undeformed chip thickness (CUCT) are explored in this paper. Experimental results indicate FTS technology can increase the CUCT from 80 nm to 580 nm. Surface and subsurface morphology tests of conventional and FTS single-crystal silicon cutting verify that FTS technology can obtain an optical surface roughness of 5 nm and lower subsurface damage. Moreover, FTS turning can reduce tool wear. Lastly, through Raman spectroscopy analysis, the amorphous phase remaining on the machined surface is lower when FTS turning is employed.

Visual inspection of long-term electroencephalography (EEG) is a tedious task for physicians in neurology. Based on bidirectional gated recurrent unit (Bi-GRU) neural network, an automatic seizure detection method is proposed in this paper to facilitate the diagnosis and treatment of epilepsy. Firstly, wavelet transforms are applied to EEG recordings for filtering pre-processing. Then the relative energies of signals in several particular frequency bands are calculated and inputted into Bi-GRU network. Afterwards, the outputs of Bi-GRU network are further processed by moving average filtering, threshold comparison and seizure merging to generate the discriminant results that the tested EEG belong to seizure or not. Evaluated on CHB-MIT scalp EEG database, the proposed seizure detection method obtained an average sensitivity of 93.89% and an average specificity of 98.49%. 124 out of 128 seizures were correctly detected and the achieved average false detection rate was 0.31 per hour on 867.14 h testing data. The results show the superiority of Bi-GRU network in seizure detection and the proposed detection method has a promising potential in the monitoring of long-term EEG.

A new robust Kalman filter (KF) based on mixing distribution is presented to address the filtering issue for a linear system with measurement loss (ML) and heavy-tailed measurement noise (HTMN) in this paper. A new Student’s t-inverse-Wishart-Gamma mixing distribution is derived to more rationally model the HTMN. By employing a discrete Bernoulli random variable (DBRV), the form of measurement likelihood function of double mixing distributions is converted from a weighted sum to an exponential product, and a hierarchical Gaussian state-space model (HGSSM) is therefore established. Finally, the system state, the intermediate random variables (IRVs) of the new STIWG distribution, and the DBRV are simultaneously estimated by utilizing the variational Bayesian (VB) method. Numerical example simulation experiment indicates that the proposed filter in this paper has superior performance than current algorithms in processing ML and HTMN.

Background: Prostate cancer (PCa) is a commonly diagnosed malignant cancer and is the second- highest cause of cancer death in men worldwide. Enzalutamide is the second-generation inhibitor of androgen receptor signaling and is the fundamental drug for the treatment of advanced PCa. However, the disease will eventually progress to metastatic castration-resistant prostate cancer (CRPC) and aggressive neuroendocrine prostate cancer (NEPC) because of androgen-deprivation therapy (ADT) resistance. The aim of the study was to investigate the role of long non-coding RNA (lncRNA) AFAP1-AS1 in ADT resistance. Methods: Quantitative real-time PCR analysis (qPCR) was used to assess the expression of AFAP1-AS1 in PCa cell lines and tissues. Cell proliferation and invasion were assessed after AFAP1-AS1 knockdown using Cell Counting Kit (CCK)-8 and Transwell assay, respectively. A dual-luciferase reporter gene assay was carried out to validate the regulatory relationship among AFAP1-AS1, microRNA (miR)-15b, and insulin-like growth factor1 receptor (IGF1R). Results: AFAP1-AS1 level was markedly increased in castration-resistant C4-2 cells and NE-like cells (PC3, DU145, and NCI-H660), compared with androgen-sensitive LNCaP cells. Enzalutamide treatment increased the expression of AFAP1-AS1 in vitro and in vivo. Functionally, AFAP1-AS1 knockdown repressed tumor cell proliferation and invasion. Mechanistically, AFAP1-AS1 functioned as an oncogene in PCa through binding to miR-15b and destroying its tumor suppressor function. Finally, we identified that AFAP1-AS1 up-regulated IGF1R expression by competitively binding to miR-15b to de-repress IGF1R. Conclusion: AFAP1-AS1 facilitates PCa progression by regulating miR-15b/IGF1R axis, indicating that AFAP1-AS1 may serve as a diagnostic biomarker and therapeutic target for PCa.

Objective: We aimed to explore the effect of Poria polysaccharide oral liquid (PPOL) on cancer-related fatigue (CRF) in postoperative patients with colorectal cancer. Methods: Fifty patients with colorectal cancer who were diagnosed in our hospital from March 2015 to March 2019 were included in this retrospective study. They were all underwent tumor resection. They were randomly divided into control group (n = 25) and observation group (n = 25). Patients in the control group were treated according to the F0LF0X4 chemotherapy regimen, and those in the observation group were treated with F0LF0X4 chemotherapy plus PPOL (10 ml/time, 3 times/day) for 6 weeks. The quality of life index (QL-index) and brief fatigue scale (BFI) were used to investigate the quality of life and fatigue, respectively. The serum levels of inflammatory factors, IL-6 and TNF-a, were measured. Results: Compared with the control group, the QL-index score in the observation group was significantly better (P< 0.05). Moreover, the BFI in the observation group was significantly lower than that in the control group (P < 0.05). Furthermore, the serum levels of IL-6 and TNF-α in the observation group were notably decreased in comparison with the control group (P < 0.05). Conclusion: PPOL can effectively improve the fatigue state of postoperative patients with colorectal cancer by reducing the levels of IL-6 and TNF- α and improving the quality of life.

Background Gastric carcinoma (GC) ranks the fifth most common cancer worldwide, with high incidence and mortality rates. Numerous microRNAs (miRNAs), including miR-654-5p, have been implicated in the pathophysiological processes of tumorigenesis. Nevertheless, the mechanism of miR-654-5p in GC is unclear. Objectives Our study is devoted to exploring the function and molecular mechanism of miR-654-5p on the malignant cell behaviors of GC. Methods The gene expression was detected by reverse transcription quantitative polymerase chain reaction. GC cell proliferation and motion were assessed by colony formation assay and transwell assay. The binding capacity between miR-654-5p and G protein-regulated inducer of neurite outgrowth 1 (GPRIN1) was explored by luciferase reporter and RNA pulldown assays. The protein levels were detected by Western blotting. Results miR-654-5p expression was higher in GC cells and tissues than control cells and tissues. miR-654-5p promoted GC cell growth and motion. Moreover, our findings showed that miR-654-5p was bound with GPRIN1. Importantly, downregulation of GPRIN1 rescued the inhibitory influence of miR-654-5p knockdown on GC cell malignant behaviors. Additionally, miR-654-5p activated the nuclear factor kappa-B (NF-κB) pathway by regulation of GPRIN1. Conclusions miR-654-5p facilitated cell proliferation, migration, and invasion in GC via targeting the GPRIN1 to activate the NF-κB pathway.

A new heavy-tailed robust Kalman filter is presented to address the issue that the linear stochastic state-space model has heavy-tailed noise with time-varying process bias. The one-step predicted probability density function (PDF) is modeled as the Student’s-t-inverse-Wishart distribution, and the likelihood PDF is modeled as the Student’s-t distribution. To acquire the approximate joint posterior PDF, the conjugate prior distributions of the state vector and auxiliary variables are set as the Gaussian, the inverse-Wishart, the Gaussian-Gamma, and the Gamma distributions, respectively. A new Gaussian hierarchical state-space model is presented by introducing auxiliary variables. Based on the proposed Gaussian hierarchical state-space model, the parameters of the proposed heavy-tailed robust filter are jointly inferred using the approach of the variational Bayesian. The simulation illustrates that the time-varying process bias is adaptively real-time estimated in this paper. In comparison with the existing cutting-edge filters, the presented heavy-tailed robust filter obtains higher accuracy.

Androgen receptor (AR) and its splice variants (AR-SVs) promote prostate cancer (PCa) growth by orchestrating transcriptional reprogramming. Mechanisms by which the low complexity and intrinsically disordered primary transactivation domain (AF-1) of AR and AR-SVs regulate transcriptional programming in PCa remains poorly defined. Using omics, live and fixed fluorescent microscopy of cells, and purified AF-1 and AR-V7 recombinant proteins we show here that AF-1 and the AR-V7 splice variant form molecular condensates by liquid–liquid phase separation (LLPS) that exhibit disorder characteristics such as rapid intracellular mobility, coactivator interaction, and euchromatin induction. The LLPS and other disorder characteristics were reversed by a class of small-molecule-selective AR-irreversible covalent antagonists (SARICA) represented herein by UT-143 that covalently and selectively bind to C406 and C327 in the AF-1 region. Interfering with LLPS formation with UT-143 or mutagenesis resulted in chromatin condensation and dissociation of AR-V7 interactome, all culminating in a transcriptionally incompetent complex. Biochemical studies suggest that C327 and C406 in the AF-1 region are critical for condensate formation, AR-V7 function, and UT-143’s irreversible AR inhibition. Therapeutically, UT-143 possesses drug-like pharmacokinetics and metabolism properties and inhibits PCa cell proliferation and tumor growth. Our work provides critical information suggesting that clinically important AR-V7 forms transcriptionally competent molecular condensates and covalently engaging C327 and C406 in AF-1, dissolves the condensates, and inhibits its function. The work also identifies a library of AF-1-binding AR and AR-SV-selective covalent inhibitors for the treatment of PCa.

Reconfigurable metasurfaces have been pursued intensively in recent years for the ability to modulate the light after fabrication. However, the optical performances of these devices are limited by the efficiency, actuation response speed and mechanical control for reconfigurability. In this paper, we propose a fast tunable optical absorber based on the critical coupling of resonance mode to absorptive medium and the plasma dispersion effect of free carriers in semiconductor. The tunable absorber structure includes a single-layer or bi-layer silicon photonic crystal slab (PCS) to induce a high-Q optical resonance, a monolayer graphene as the absorption material, and bottom reflector to remove transmission. By modulating the refractive index of PCS via the plasma dispersion of the free carrier, the critical coupling condition is shifted in spectrum, and the device acquires tuning capability between perfect absorption and total reflection of the incident monochromatic light beam. Simulation results show that, with silicon index change of 0.015, the tunable absorption of light can achieve the reflection/absorption switching, and full range of reflection phase control is feasible in the over coupling region. The proposed reconfigurable structure has potential applications in remote sensing, free-space communications, LiDAR, and imaging.

The field of forensics leans heavily on the development of novel methods of crime scene analysis. Many of these methods have their roots in biology and chemistry laboratories. Our research describes how plants may allow indirect detection of a buried human body. We hypothesized that specific molecules from a buried cadaver are absorbed by nearby plant systems during decomposition. We grew two flowering plants from seed: Cosmos bipinnatus (Cosmos) and Rudbeckia hirta (Black-Eyed Susan). Ground beef was buried in some of the pots to imitate organic matter from a human cadaver. After 3 weeks, we collected plant and soil samples, and analyzed them using thin layer chromatography and mass spectrometry, to identify bovine proteins, hormones, and amino acids. The thin layer chromatography profiles suggested that specific proteins from the beef were also present in our plant samples. This indicates that the plants grown with beef in the soil actively absorbed beef proteins, supporting our hypothesis. Mass spectrometry data will confirm our hypothesis. Further experiments can be done to supplement our preliminary data. If our results prove to be authentic and reproducible, they may provide a basis for the development of new forensics tools to detect the presence of human remains. If developed, these tools could greatly contribute to the efficiency and accuracy of evidence collection at crime scenes., Journal of Student-Scientists' Research, Vol. 2 (2020)

Lithium-ion batteries (LIBs) have been widely employed in energy-storage applications owing to the relatively higher energy density and longer cycling life. However, they still need further improvement especially on the energy density to satisfy the increasing demands on the market. In this respect, the irreversible capacity loss (ICL) in the initial cycle is a critical challenge due to the lithium loss during the formation of solid electrolyte interphase (SEI) layer on the anode surface. The strategy of prelithiation was then proposed to compensate for the ICL in the anode and recover the energy density. Here, various methods of the prelithiation are summarized and classified according to the basic working mechanism. Further, considering the critical importance and promising progress of prelithiation in both fundamental research and real applications, this Review article is intended to discuss the considerations involved in the selection of prelithiation reagents/strategies and the electrochemical performance in full-cells. Moreover, insights are provided regarding the practical application prospects and the challenges that still need to be addressed.

We present the design, fabrication, and characterization of suspended arrays of small volume, high quality factor (Q) silicon nitride photonic crystal nanobeam (PCNB) cavities with lateral nanorod fin structures. By controlling the alignment position of the fins with respect to the air holes, the resonance wavelength and Q-factor of the PCNB cavities can be tuned to realize the desired performance. Measured tunable range of 2 × 104 and 10 nm is achieved for Q-factor and resonance wavelength, respectively, with the highest Q-factor measured at 2.5 × 104. Incorporating such nanorod fins into the nanobeam cavity is demonstrated to provide improved mechanical support, thermal transport, and channels of lateral carrier injection for the suspended PCNB. The proposed PCNB cavities with lateral fins are advantageous for energy efficient, ultra-compact lasers, modulators, filters, and sensors.

The relatively narrow electrochemical steady window and low ionic conductivity are two critical challenges for Li+ -conducting solid polymer electrolytes (SPE). Here, a family of poly-oxalate(POE) structures were prepared as SPE; among them, POEs composed from diols with an odd number of carbons show higher ionic conductivity than those composed from diols with an even number of carbons, and the POE composed from propanediol (C5-POE) has the highest Li+ conductivity. The HOMO (highest occupied molecular orbital) electrons of POE were found located on the terminal units. When using trifluoroacetate as the terminating unit (POE-F), not only does the HOMO become more negative, but also the HOMO electrons shift to the middle oxalate units, improving the antioxidative capability. Furthermore, the interfacial compatibility across the Li-metal/POE-F is also improved by the generation of a LiF-based solid-electrolyte-interlayer(SEI). With the trifluoroacetate-terminated C5-POE (C5-POE-F) as the electrolyte and Li+ -conducting binder in the cathode, the all-solid-state Li/LiNi0.8 Mn0.1 Co0.1 O2 (NMC811) cells showed significantly improved stability than the counterpart with poly-ether, providing a promising candidate for the forthcoming all-solid-state high-voltage Li-metal batteries.

Purpose: This study was designed to reveal the molecular differences between granulosa cells (GCs) from patients with endometriosis and normal controls. Methods: RNA sequencing was performed on GCs...