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The percentage of glycated hemoglobin (HbA1c) in total hemoglobin (Hb) is an important index for the diagnosis of Type II diabetes (T2D) because it reflects the long-term glucose level in blood. Herein, employing a one-pot co-reduction approach using glutathione (GSH) as structure-directing agent, a cluster-like AuAg nanoparticle (AuAg NPs) material was synthesized, therefore an electrochemiluminescence (ECL) aptamer-sensor for HbA1c detection was developed based on functionalized electrode with this material. Meanwhile, the quantitative determination of total Hb was realized based on the quenching effect of Hb on the fluorescence (FL) of luminol. Under compatible conditions, the results of both indexes can be satisfactorily acquired. This multimodal detection system has a good linear response toward Hb from 0.1 to 2.5 μM and HbA1c from 0.005 to 0.5 μM. The blood test proves this strategy is capable of accurate Hb and HbA1c detection, thus to obtain the percentage of HbA1c in total Hb (HbA1c%), which has the potential application for clinical diagnosis of diabetes mellitus.

The clinical use of 5-fluorouracil (5-FU), a potent antitumor agent, was limited by severe cardiotoxic effects. The present study was aimed to investigate the protective effects of resveratrol (Res) on 5-FU-induced cardiotoxicity and to explore its potential mechanisms.The cardiotoxicity model was intraperitoneal injection of 5-FU at the dose of 30 mg/kg for 7 consecutive days. Plasma enzymes activities, cardiac tissues were assessed after treatment with Res for 3 weeks. Ferrostatin-1 (Fer-1) was used as ferroptosis inhibitor. In H9c2 cardiomyocyte cells, cell viability, generation of reactive oxygen species (ROS), mitochondrial activity and cellular Fe

A novel approach for the preparation of few-layer graphene nano-flakes (GNFs) is presented in this paper. The GNFs are continuously synthesized by thermal decomposition of hydrocarbons using a magnetically rotating arc at atmospheric pressure. The effects of magnetic field, arc current, feedstock gas flow rate, and feedstock gas type on the morphologies and microstructures of pyrolysis products are investigated and discussed. Results show that the microscopic characteristics of pyrolysis products are affected by the operating parameters. High temperature and high hydrogen concentration are considered the essential condition for the formation of GNFs. The synthesized GNFs are agglomerative flakes, where each flake is between 50 and 300 nm. Material analyses indicates that the GNFs have excellent properties such as a good crystalline structure, a low number of layers, and a large specific surface area. This indicates that the GNFs could be applied in fuel cells and energy storages. This method is suitable for mass production of few-layer GNFs since it is a continuous process with a relatively high yield (∼14%) and a relatively low energy cost (∼0.4 kWh/g).

Imatinib Mesylate (IMA) has been widely used to treat with chronic myeloid leukemia (CML). However, cardiotoxicity associated with IMA is included among the therapeutic strategies. The present study was aimed to discover whether ferroptosis, a programmed iron-dependent cell death, is involved in IMA-induced cardiotoxicity. In vivo, mouse model was established after treated with 25 mg/kg, 50 mg/kg and 100 mg/kg IMA. Serum CK, LDH, AST activities were determined. Cardiac tissues were examined by HE and Oil Red O staining. MDA was measured to assess production of lipid peroxide. Tissue iron and GSH content were measured. In vitro, cell viability, mitochondria membrane potential, generation of reactive oxygen species (ROS) and cellular iron levels were performed to explore the mechanism of IMA. The in vivo results revealed that IMA treatment significantly increased serum CK, LDH and AST. HE staining showed that IMA caused cardiac structural injuries. The dose-dependent decrease of GSH and increase of tissue iron and MDA were observed in IMA-treated groups. Oil Red O staining suggested obvious cardiac lipid accumulation after treated with IMA. In H9c2 cardiomyocytes, IMA significantly inhibited cell proliferation in a dose-dependent manner. Mitochondria membrane potential assay showed that IMA destroyed the mitochondrial function. Additionally, IMA increased the cellular ROS and iron levels. Furthermore, IMA down-regulated the expression of Nrf2 and up-regulated the expression of P53 and TfR. These results provided compelling evidence that ferroptosis participates in IMA-induced cardiotoxicity. Ferroptosis could be regarded as a target to protect against cardiotoxicity in IMA-exposed patients.

A cluster-like AuAg alloy hollow-nanoparticles (HNPs), synthesized by facile one-pot co-reduction under the guidance of bovine serum albumin (BSA), enhanced the electrochemiluminescence (ECL) of luminol, thus to be served as the sensing matrix of the enzymatic glucose biosensor. The prepared HNPs were characterized by electronic microscopy, UV–Vis spectrometry, IR spectrometry, X-ray diffraction analysis, X-ray photoelectron spectroscopy and electrochemistry. Using hydrolyzed APTMS to connect AuAg HNPs on indium tin oxide (ITO) coated glass, the synergistic effect between two metals makes it had 20 multiple enhancement of ECL, and shows sensitive response toward reactive oxygen species. After loading GOD on this matrix to build the glucose sensor, it has a wide linear response range for the glucose from 5.0 μM to 1.0 mM with a detection limit as 0.40 μM. It can be applied for noninvasive detection of glucose with saliva as specimen, the results indicated the high-degree correlation of glucose contents between saliva and blood.

A non-thermal plasma source based on magnetically stabilized gliding arc discharge (MSGAD) was used to prepare carbon nanoparticles via methane decomposition. Spherical carbon nanoparticles (SCNs), few-layer graphene nanoflakes (GNFs), and nitrogen-doped carbon nanoparticles were obtained. The results showed that the product microstructure was influenced by the buffer gas. In pure methane and argon, the products were a mixture of SCNs and GNFs. In helium and hydrogen, all products were highly crystalline GNFs with low defects, few layers, large BET surface areas, and excellent thermal stability. Under a nitrogen atmosphere, nitrogen-doped nanoparticles were formed, and the products were a mixture of GNFs, disordered graphitic layers, and tiny spots similar to carbon dots. The formation of GNFs was possibly related to the high input power and abundant hydrogen atoms, while the complex product morphology obtained under a nitrogen atmosphere was likely caused by the incorporation of nitrogen atoms.

Few-layer graphene nano-flakes (GNFs) are successfully prepared via hydrocarbon pyrolysis using a non-thermal plasma process based on a magnetically stabilized gliding arc discharge (MSGAD) at atmospheric pressure. The effects of feedstock gas type and hydrogen flow rate on the morphology of carbon nanomaterials are investigated. When the hydrogen/carbon (H/C) molar ratio is 4, the synthesized GNFs consist of 10 layers per stack with dimensions between 100 and 300 nm in a 4.57.2% yield. The energy cost is 0.1–0.2 kWh/g, which makes this process feasible for large-scale GNFs production. The results show that appropriately increasing the H/C molar ratio promotes the morphological transformation of carbon nanomaterials from spherical carbon nanoparticles (SCNs) to GNFs, improve the quality of GNFs and reduce the stacking of graphite layers. However, increasing the H/C ratio reduces the yields of carbon nanomaterials, so as to increase the energy cost. Analysis suggests that increasing the H/C ratio reduces the concentration of polycyclic aromatic hydrocarbon (PAH) and generates more H atoms, which helps form a two-dimensional nucleation and promotes planar growth. However, an excessive H/C ratio may introduce some defects due to an etching effect.

A novel non-thermal plasma process based on magnetically stabilized gliding arc discharge (MSGAD) is developed for continuous synthesis of carbon nano-onions (CNOs). CNOs with a diameter range of 70–200 nm are continuously prepared by propane decomposition. Results indicate that with increased residence time in the plasma region, the product morphology gradually changes from graphene nanoflakes (GNFs) to CNOs. It is proposed that CNOs synthesis mainly includes three stages: formation of GNFs, curving and closure of multiple GNFs, further graphitization. In addition, H2 content has a key role in CNOs formation since hydrogen has a significant effect on the formation and morphology of GNFs.

It has been documented that diseases can spread within an aircraft cabin from the sneezing, coughing or breathing of a sick passenger. To understand the spreading mechanism it is very important to quantify the airflow and droplet transmission around a sneezing/coughing incident. In this project, tracer gas experiments were carried out in a full-scale Boeing 767-300 mock-up to study the global transport process of contaminated air within the cabin. Computational fluid dynamics (CFD) simulation was also used to provide additional information for understanding the principle. A steady airflow field was simulated first and then it was compared with the experimental data. The global airflow patterns were similar to those observed experimentally. This velocity field was adopted as the initial condition for further unsteady pollutant transport simulation. Experimental and simulated results were compared and discussed to develop a relationship between concentration and airflow pattern, source location, transport direction, and ventilation rate. Finally, the overall picture of concentration evolution by both experimental and simulated approaches was discussed.

Air age is an important index to evaluate indoor air quality in ventilated rooms. Current definition of air age is limited to indoor part, i.e., the air age at the inlets of air supply diffusers is assumed to be zero. This work extends the air age concept to the so-called “total air age” by considering the impact of air delivery process on air age. The air age in duct is solved using one-dimensional flow characteristic, which includes the mixing process between airflows with different ages. It is then coupled with the room air age which is solved using computational fluid dynamics technique. An iterative algorithm is proposed to calculate total air age in general ventilation systems and a direct method is further derived for systems with only one air handling unit. Two examples are given to demonstrate the calculation of total air age and the distributions of total air age are compared with those of traditional air age.

This paper presents a method for synthesizing a recursive linear time-variant digital filter in finite time domain. The desired filter can be nonrecursive and is given by its generalized frequency function. The synthesized filter is described by a linear difference equation with time-variant coefficients. These coefficients at a given time instant are derived recursively from those at the previous instants. In addition, for the determined coefficients at the previous instants, the coefficients at the given instant minimize the error between the generalized frequency function of the desired filter and that of the synthesized one at the given instant. The performance of this method is illustrated and compared with another available method through numerical examples. The results show an improvement of nearly two order of magnitude in the normalized mean squared error between the amplitudes of the generalized frequency function of the desired filter and that of the synthesized.

In this paper the rejection of a narrow-band interference in DS (direct-sequence) spread spectrum communication systems by a digital filter is explored. A method for estimating the dominant frequency of the interference is presented. According to the estimated frequency the filter coefficients of a bandpass error filter are generated such that its centre frequency is at the estimated one. This error filter is realized by a recursive structure with only six multiplications and is approximately of zero phase. The interference is suppressed by compensating the non-filtered signal with the filtered one. A method to extract the characteristics of the different type of interferences is also presented in order to adjust the filter to make it suitable for their rejection. The performances of the filter in the environment of a white Gaussian noise and a narrow-band interference such as single-tone, swept-tone and narrow-band Gaussian interferences are simulated by computer, which shows that by using the given filter, the system performance can be greatly improved.