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Atmospheric aerosols play a pivotal role in the earth-atmospheric system. Analyzing their optical properties, specifically absorption and scattering coefficients, is essential for comprehending the impact of aerosols on climate. When different optical properties of aerosols are individually measured using multiple devices, cumulative errors in the detection results inevitably occur. To address this challenge, based on photoacoustic spectroscopy (PAS) and integrating sphere (IS) scattering enhancement, a compact gas cell (PASIS-Cell) was developed. The PASIS-Cell comprises a dual-T-type photoacoustic cell (DTPAC) and an IS. IS is coupled with DTPAC through a transparent quartz tube, thereby enhancing the scattering signal without compromising the acoustic characteristics of DTPAC. Concurrently, DTPAC can realize high-performance photoacoustic detection of absorption signal. Experimental results demonstrate that PASIS-Cell can simultaneously invert atmospheric aerosol absorption and scattering coefficients, with a minimum detection limit of less than 1 Mm−1, showcasing its potential in the analysis of aerosol optical properties.

In intelligent transportation systems, it is crucial for smart vehicles to broadcast real-time vehicle track messages to coordinate driving decisions and ensure driving safety.However, attackers can manipulate vehicle tracks by modifying timestamps or manipulating signal frequencies, posing a threat to security.To address this problem, a lightweight vehicle track verification scheme was proposed, utilizing the broadcast communication channels to achieve secure verification of vehicle tracks without any special hardware support.Without time synchronization, each verifier calculated the time interval between the reception time of the message and the sending timestamp.Spatial position constraint equations are formulated by combining these time intervals between any two verifiers, effectively defending against timestamp forgery attacks.Additionally, each verifier calculates the Doppler frequency shift between the arrival frequency and the scheduled transmit frequency.Velocity vector constraint equations were formulated by combining these frequency shifts between any two verifiers, providing defense against carrier frequency manipulation attacks.Formal analysis shows that increasing the number of verifiers improves the accuracy of the proposed verification scheme.Experimental results in a real-world environment further validate that the proposed verification scheme exhibits the best performance when the number of verifiers is set to 3.Compared to the existing solution, the proposed verification scheme has a higher accuracy, lower false rejection rate, and lower false acceptance rate when validating true vehicle track and false vehicle track separately.

Abstract Background To evaluate the glycemic control effects of vhiglitazar (carfloglitazar), a novel peroxisome proliferator‐activated receptor pan‐agonist, in patients with type 2 diabetes mellitus (T2DM) with metabolic syndrome (MetS) or insulin resistance (IR) using pooled data analysis of two phase III clinical trials. Methods Data were collected from two randomized phase III clinical trials in China, comparing chiglitazar to placebo or sitagliptin in T2DM patients. The MetS was defined by the Adult Treatment Panel III MetS criteria, and IR was defined by homeostatic model assessment for insulin resistance (HOMA‐IR) ≥4.31 (male) or 4.51 (female). The main end point of this analysis was glycemic control in the different arms within each subgroup. Results In the MetS subgroup, changes in glycated hemoglobin (HbA1c) from baseline at week 24 in the chiglitazar 32 mg, chiglitazar 48 mg, and sitagliptin 100 mg arms were −1.44%, −1.68%, and −1.37%, respectively; p

This study focuses on the semiconductive silicone rubber of 10 kV cold-shrink accessories. Accelerated thermal aging tests were conducted on the semiconductive silicone rubber, obtaining tensile stress–strain curves at various time points after thermal aging. The corresponding parameters of the Yeoh hyperelastic model were calculated. The results indicate that the initial shear modulus of the samples decreases with the increase in the aging temperature and time. Microscopic morphology, changes in cross-sectional content, thermal residual values, and chemical structure changes of the samples after aging were studied using electron microscopy, EDS testing, TG curves, and Fourier spectra. The results show that the surface roughness of the aged semiconductive silicon rubber increases, the residual values decrease, the thermal stability decreases, the main chain absorbance decreases, the main chain integrity decreases, and the organic functional groups Si-CH3 and Si(CH3)2 decrease, leading to a reduction in organic content.

Histone deacetylase (HDAC) is one of the most characterized epigenetic modifiers, modulating chromatin structure and gene expression, which plays an important role in cell cycle, differentiation and apoptosis. Dysregulation of HDAC promotes cancer progression, thus inhibitors targeting HDACs have evidently shown therapeutic efficacy in multiple cancers. Tucidinostat (formerly known as chidamide), a novel subtype-selective HDAC inhibitor, inhibits Class I HDAC1, HDAC2, HDAC3, as well as Class IIb HDAC10. Tucidinostat is approved in relapsed or refractory (R/R) peripheral T-cell lymphoma (PTCL), advanced breast cancer and R/R adult T-cell leukemia-lymphoma (ATLL). Compared with other HDAC inhibitors, tucidinostat shows notable antitumor activity, remarkable synergistic effect with immunotherapy, and manageable toxicity. Here, we comprehensively summarize recent advances in tucidinostat as both monotherapy and a regimen of combination therapy in both hematological and solid malignancies in clinic. Further studies will endeavor to identify more combination strategies with tucidinostat and to identify specific clinical biomarkers to predict the therapeutic effect.

Raman spectroscopy is widely used in many fields with the advantages of simultaneous species detection and molecular fingerprint characteristics, but the low detection sensitivity limits its further development, especially for highly scattering or turbid mediums. In this consideration, a new method called quartz tube enhanced Raman scattering spectroscopy was proposed for the first time in this paper. A quartz tube was inserted into the powder sample to improve the coupling of light into the medium and increase the interaction volume of the laser with the sample (“volume-excitation”), multiple scattering of the light within the turbid medium resulted in an increased Raman signal. In this paper, the effect of different sizes of quartz tubes on the sensitivity enhancement was studied. The results show that the enhancement factor of the signal intensity was nearly 5.37 (the Raman signal of HCO3−) compared to traditional Raman spectroscopy technology. Furthermore, the method was successfully applied to improve the Raman signal intensity of the mixed sample (1:5, m (PO43−):m (HCO3−)) and detect the baking soda powder buried under a 6 mm thick layer of potassium dihydrogen phosphate powder. The results show that the technology will open a new way for the quantitative analysis and detection of powder samples.

The study of brain science is vital to human health. The application of hyperspectral imaging in biomedical fields has grown dramatically in recent years due to their unique optical imaging method and multidimensional information acquisition. Hyperspectral imaging technology can acquire two-dimensional spatial information and one-dimensional spectral information of biological samples simultaneously, covering the ultraviolet, visible and infrared spectral ranges with high spectral resolution, which can provide diagnostic information about the physiological, morphological and biochemical components of tissues and organs. This technology also presents finer spectral features for brain imaging studies, and further provides more auxiliary information for cerebral disease research. This paper reviews the recent advance of hyperspectral imaging in cerebral diagnosis. Firstly, the experimental setup, image acquisition and pre-processing, and analysis methods of hyperspectral technology were introduced. Secondly, the latest research progress and applications of hyperspectral imaging in brain tissue metabolism, hemodynamics, and brain cancer diagnosis in recent years were summarized briefly. Finally, the limitations of the application of hyperspectral imaging in cerebral disease diagnosis field were analyzed, and the future development direction was proposed.

Abstract Background Chiauranib is a novel orally active multi-target inhibitor that simultaneously inhibits the angiogenesis-related kinases (VEGFR2, VEGFR1, VEGFR3, PDGFRα, and c-Kit), mitosis-related kinase Aurora B, and chronic inflammation-related kinase CSF-1R. This phase I dose-escalation study was to determine the maximum tolerated dose (MTD), safety, pharmacokinetics, and preliminary antitumor activity of chiauranib in patients with refractory advanced solid tumor and lymphoma. Methods Eighteen patients were treated with continuous dosing of chiauranib from 10 to 65 mg once daily in a dose-escalation 3 + 3 design and evaluated in 28-day cycles. Pharmacokinetic profile of plasma chiauranib was analyzed in both single and multiple dose studies. Results Dose-limiting toxicity (DLT) as of grade 3 hypertension occurred in two patients at 65 mg/day, and one dose level below as MTD was 50 mg/day. The most common treatment-related adverse events included fatigue (61.1%), proteinuria (44.4%), hematuria (38.9%), hypothyroidism (38.9%), hypertriglyceridemia (33.3%), and hypertension (33.3%). A linear and dose-dependent pharmacokinetic profile of chiauranib was characterized with rapid absorption and slow elimination feature in both single and multiple dose studies. The accumulative exposure of chiauranib reached the steady state within 8 days and was approximately increased by twofold as those in the single dose study. No complete or partial response was observed, and 12 patients (66.7%) achieved stable disease (SD). Conclusions Chiauranib demonstrated an acceptable safety and favorable pharmacokinetic profile with potential antitumor activity. Several phase Ib/II clinical studies are currently under further investigation. Trial registration NCT, NCT02122809. Registered 25 April 2014

The concentration of trace gases in the atmospheric environment is extremely low, but it has a great impact on the living environment of organisms. Photoacoustic spectroscopy has attracted extensive attention in the field of trace gas detection because of its high sensitivity, good selectivity, and fast response. As the core of a photoacoustic detection setup, the photoacoustic cell has a significant impact on detection performance. To improve detection sensitivity, a sphere-tube coupled photoacoustic cell (STPAC) was developed, which was mainly composed of a diffuse-reflective sphere and an acoustic resonance tube. Modulated light was reflected multiple times in the sphere to increase optical path, and photoacoustic (PA) signals were further amplified by the tube. Based on STPAC, a PA gas detection setup was built with a laser diode (LD) at 450 nm as the light source. The experimental results showed that the minimum detection limit (noise equivalent concentration, NEC) of NO2 was ~0.7 parts per billion (ppb). Compared with the T-type PA cell (TPAC) in which the modulated light passed through the sphere, the signal-to-noise ratio of STPAC was increased by an order of magnitude at the same concentration of the NO2 sample.

Abstract Purpose The present review aimed to assess the role of exosomal miRNAs in cancer-associated fibroblasts (CAFs), normal fibroblasts (NFs), and cancer cells. The roles of exosomal miRNAs and miRNA dysregulation in CAF formation and activation were summarized. Methods All relevant publications were retrieved from the PubMed database, with key words such as CAFs, CAF, stromal fibroblasts, cancer-associated fibroblasts, miRNA, exosomal, exosome, and similar terms. Results Recent studies have revealed that CAFs, NFs, and cancer cells can secrete exosomal miRNAs to affect each other. Dysregulation of miRNAs and exosomal miRNAs influence the formation and activation of CAFs. Furthermore, miRNA dysregulation in CAFs is considered to be associated with a secretory phenotype change, tumor invasion, tumor migration and metastasis, drug resistance, and poor prognosis. Conclusions Finding of exosomal miRNA secretion provides novel insights into communication among CAFs, NFs, and cancer cells. MicroRNA dysregulation is also involved in the whole processes of CAF formation and function. Dysregulation of miRNAs in CAFs can affect the secretory phenotype of the latter cells.

The extraction of Cu and Ni from low-Ni matte in an efficient and green manner is essential to harvest value-added metals with minimum environmental footprint. Herein, a combined approach of chemical precipitation and molten salt electrolysis was used to extract valuable metals (Cu and Ni) from the low-Ni matte. First, the low-Ni matte was converted and separated into CuS and NiS by ammonium chloride roasting, and then, it was water leached and precipitated. Fe was removed from the leachate solution by adjusting the pH value, and the separation of Cu and Ni was carried out by adjusting the temperature, S-to-Ni molar ratio, and precipitation time. The obtained CuS and NiS were then separately converted to sulfur gas at the anode and Cu and Ni at the cathode in molten NaCl-KCl. The reduction behaviors of CuS and NiS were studied using cyclic voltammetry (CV). This study proposes an eco-friendly way to extract valuable metals from low-Ni matte. [ABSTRACT FROM AUTHOR]

Silicon (Si)/carbon (C) composites, silicon carbide (SiC), and Si films are electrochemically prepared in molten CaCl2, and the interaction of Si with C is systematically analyzed. Further, the effects of the cell voltage of electrolysis and the formation of SiO2 and C on the electrolytic products were studied. Electrolytic SiC can be identified as the thermodynamically favored product because the Gibbs free energy of formation of SiC is negative at 850°C. The electrolysis of the C/SiO2 mixture prepared by the mechanical mixing of the C (i.e., graphite or sugar-derived C) and SiO2 powders resulted in the generation of the thermodynamically unfavored Si/C composite. Further, the thermodynamically favored SiC was obtained by the electrolysis of SiO2 coated with sugar-derived C. Moreover, the electrodeposition of Si films onto both graphite foils and C fibers was conducted in molten CaCl2, and the boundary of the electrolytic Si film/C substrate was obtained using scanning electron microscopy and X-ray photoelectron spectroscopy. Overall, the contact area between SiO2 and C is required for engineering the electrolysis to obtain products such as the Si/C composites, SiC, and Si films. [ABSTRACT FROM AUTHOR]

Extraction of lead and antimony from their sulfides without SO2 emission is of great significance to tackle the air pollution caused by the conventional metallurgical routes. In the paper, solid PbS and Sb2S3 are respectively electrochemically reduced to Pb and Sb in a 50 wt% NaOH solution. Thermodynamic analysis is conducted to illustrate the feasibility of extracting metals from their sulfides in the alkaline solution. Moreover, a home-made graphite cavity working electrode was employed to study the electrochemical reduction behaviors of PbS and Sb2S3, and their reduction processes were in situ recorded by a camera in a transparent cell. The results show that the strong alkaline solution is able to electrochemically convert PbS and Sb2S3 into Pb and Sb with a current efficiency higher than 90%. [ABSTRACT FROM AUTHOR]

The gas generated on a commonly used carbon anode is highly related to the efficiency of electrolysis and the purity of cathodic products in molten CaCl2.Herein, the anodic gas generated on a carbonworking electrode in a three-electrode setupwas systematically analyzed using a gas chromatograph under controlled potentials in both molten CaCl2 and CaCl2-1 wt%CaO. Two successive oxidation steps of the graphite electrode were observed. The anodic gas contains both CO and CO2 with an atomic ratio (CO/CO2) of 0.076, 0.072, 0.073, and 0.144 under anodic potentials of 0V, 0.2V, 0.4V, and 0.6V (vs. Ag/AgCl) in molten CaCl2, respectively, while the atomic ratios of CO/CO2 are 3.639, 2.008, 1.666, 0.720 in molten CaCl2-1 wt%CaO. Therefore, CaO remarkably enhances the kinetics of the formation of CO and absorption of the generated CO2 forming CO32- that could decrease the efficiency of the electrolysis and purity of cathodic products. [ABSTRACT FROM AUTHOR]

An electrochemical approach is able to convert low-grade nickel-copper matte (LNCM) to copper-, nickel-, and iron-alloys in both molten NaCl-KCl and MgCl2-NaCl-KCl without sulfur dioxide emissions. Since the LNCM contains the mixture of sulfides and oxides, the electrochemical deoxidation and desulfurization are taking place together, producing alloys in a one-step process. Thermodynamic properties of several sulfides/oxides were analyzed, and the electrochemical reduction behaviors of LNCM were investigated in by cyclic voltammetry (CV) using a powder modified working electrode. The morphologies of the electrolytic products could be tailored by adjusting both operating temperature and cell voltage of the electrolysis. Overall, this paper provides an environment-friendly pathway to comprehensively utilize minerals in molten salts. [ABSTRACT FROM AUTHOR]

The interfacial and electrochemical reactions on the passivation layers of chalcopyrite in alkaline solution was investigated. Fe was selectively leached out prior to Cu to form Fe--oxide and Fe--deficient Cu polysulfide layers in a series of tests. The results of the leaching experiments showed that the distribution of FeOOH and Fe2O3 with respect to depth of the passive layers was inhomogeneous. The composition of FeOOH reached a maximum at the surface (51.28 to 115.38 nm). Additionally, a transitional layer between oxides and sulfides consisting of Fe2O3, Cu sulfides, and Cu1-xFe1-yS2 (around 115.38 nm) exists with a fragile and strippable structure. The electrochemical experiments revealed that the key potential between the passive and trans-passive region is 0.3 VSCE. In the passive region, the chalcopyrite can be either passive or active depending on how it was brought to that potential. The semiconducting property of the chalcopyrite was demonstrated to exist but has minimal impact on the chalcopyrite leaching process compared to passivation and dissolution. At the trans-passive region, S0 was found at the potential of 0.4 VSCE, while sulfides were oxidized to sulfur species after 0.5 VSCE. [ABSTRACT FROM AUTHOR]

Cu-Mn alloy powder was prepared by electrochemical reduction of a CuO and MnO2 mixture in a eutectic CaCl2-NaCl molten salt. The reduction pathway was probed by examining the partially reduced samples for various durations. The influence of the working temperature on the reduction was discussed. The Cu-Mn powder obtained was applied as a catalyst for methanol synthesis. The products before and after catalysis were characterized to investigate the possibility of the alloy as a catalyst for methanol synthesis. The results show that the Cu-Mn alloys, including CuMn4 and CuMn were successfully synthesized. The alloys were made up of interconnected nodular particles with a three-dimensional framework structure. The particles provided more adequate locations for catalytic reactions than the particles produced from mechanical alloying. The increased working temperature promoted the alloying process of CuMn4 and Cu to form CuMn. The electrolytic products of CuMn and CuMn4 were beneficial to synthesize methanol. The CH3OH selectivity was maintained at greater than 93%, obviously better that of the reference catalysts. MnO was formed on the top surface of the alloy particles during catalysis, separating the Cu-Mn alloys from the feed gas. This phenomenon decreased the performance of the Cu-Mn alloys for methanol synthesis. [ABSTRACT FROM AUTHOR]

A carbon film was electrochemically deposited on 304 stainless steel by reduction of carbonate ions in molten LiCl-KCl-K2CO3. A Cr-O-C interlayer was prepared by a joint process of thermal exposure of the steel in air and subsequent electrochemical reactions in molten salt for the enhancement of adhesion between the carbon film and the substrate. The bilayer film was delaminated gradually using electrochemical polarization in an aqueous NaCl solution, and was characterized by XRD, SEM, and XPS. Chromium element aggregates in the oxide scale from the 304 stainless steel substrate during the oxidation process, and transforms to chromium oxycarbide during electro-deoxidation of the oxide scale and diffusion of carbon nucleated from electro-reduction of carbonate ions. The interlayer mainly presents the CrO1.13C0.12 phase, which contains Cr-C and Cr-O bonds confirmed by XPS analysis. The presence of the CrO1.13C0.12 interlayer is an important factor for a continuous and adhesive carbon film on 304 stainless steel. [ABSTRACT FROM AUTHOR]