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Exopolysaccharides (EPS) can not only give food a unique texture but also has antioxidant capacities. To select the medium composition that influences the yield and antioxidative activity of EPS, Plackett–Burman (PB) design was employed to appraise the effects of carbon sources, nitrogen sources, and inorganic salts on yield and DPPH free radical scavenging (DPPH-FRS) rate of EPS in MRS medium fermented by Lactobacillus fermentum B62. The result indicated that sucrose (p2PO4 (p2PO4 (p2PO4)2 (p2PO4 (p2H3NaO2 (p2PO4 all showed significant positive relativity to the yield and anti-oxidative activity of EPS.

SnO2 has been extensively used in the detection of various gases. As a gas sensing material, SnO2 has excellent physical-chemical properties, high reliability, and short adsorption-desorption time. The application of the traditional SnO2 gas sensor is limited due to its higher work-temperature, low gas response, and poor selectivity. Nanomaterials can significantly impact gas-sensitive properties due to the quantum size, surface, and small size effects of nanomaterials. By applying nanotechnology to the preparation of SnO2, the SnO2 nanomaterial-based sensors could show better performance, which greatly expands the application of SnO2 gas sensors. In this review, the preparation method of the SnO2 nanostructure, the types of gas detected, and the improvements of SnO2 gas-sensing performances via elemental modification are introduced as well as the future development of SnO2 is discussed.

A gas sensor fabricated with a two-dimensional Ti3C2TX MXene@TiO2/MoS2 heterostructure exhibits fast response/recovery time, excellent long-term stability and outstanding selectivity at room temperature, making it a promising candidate for practical detectors of NH3.

Hazardous gases have been strongly associated with being a detriment to human life within the environment. The development of a reliable gas sensor with high response and selectivity is of great significance for detecting different hazardous gases. TiO2 nanomaterials are promising candidates with great potential and excellent performance in gas sensor applications, such as hydrogen, acetone, ammonia, and ethanol detection. This review begins with a detailed discussion of the different dimensional morphologies of TiO2, which affect the gas sensing performance of TiO2 sensors. The diverse morphologies of TiO2 can easily be tuned by regulating the manufacturing conditions. Meanwhile, they exhibit unique characteristics for detecting gases, including large specific surface area, superior electron transport rates, extraordinary permeability, and active reaction sites, which offer new opportunities to improve the gas sensing properties. In addition, a variety of efforts have been made to functional TiO2 nanomaterials to further enhance sensing properties, including TiO2-based composites and light-assisted gas sensors. The enhanced gas sensing mechanisms of multi-component composite nanomaterials based on TiO2 include loaded noble metals, doped elements, constructed heterojunctions, and compounded with other functional materials. Finally, several studies have been summarized to demonstrate the comparative sensing properties of TiO2-based gas sensors.

This paper reports the synthesis of ZnO-SnO2 nanocomposites modified by PdO nanoparticles named PdO-ZSO which are prepared by the one-step hydrothermal method at 160 °C for 12 h and gas sensing test to H2 and C4H10 inflammable gas. Meanwhile, PdO-ZSO nanoparticles are XRD, SEM, TEM, EDS, XPS and other characterization methods to further explain its morphological formation process. As the sensing materials, PdO-ZSO exhibits extraordinary gas sensing behaviors for hydrogen (H2) and butane (C4H10) and the response reaches 98 and 58 to H2 and C4H10 at operating temperature of 370 °C, respectively. And the response time and recovery time are both less than 2 s and 4 s respectively, with good repeatability and outstanding long-term stability. The existence of PdO is able to increase the resistance modulation range of heterostructure. And the enhanced gas sensing performances can be ascribed to the catalysis of noble metal doping and the formation of ternary heterostructure between PdO and ZnO-SnO2 nanocomposites.

It is highly desirable to develop sensors with high response and selectivity at room temperature of operating temperature. Besides, efficient and low-cost sensors are also required for future social development. In this paper, it is developed a detector with two-dimensional (2D) material of Ti3C2Tx MXene sensing material by a chemical etchant for ammonia sensing, which shows high response and excellent selectivity to ammonia (NH3) at room temperature of operating temperature. A key point of this work is the thermal treatment temperature of the sensing ceramic tube at 280 °C, which removes the adsorbed water and partially oxidized the material. In ambient condition, Ti3C2Tx MXene-280 shows the response to 500 ppm NH3 with 147 %, and the counterpart response and recovery time are 67 and 157 s at room temperature of operating temperature, respectively. In the environment of different relative humidity, its sensing performance is maintained at around 50 % of the initial performance, which shows great moisture resistance. The higher response and good selectivity of Ti3C2Tx MXene-280 sensor to NH3 at room temperature are ascribed to the powerful hydrogen bond formed between the OH−, O2− functional groups on Ti3C2Tx MXene-280 and NH3, as well as the synergistic effect of TiO2 and Ti3C2Tx MXene, generated after heating treatment, which increases the electron transport efficiency. The results demonstrated that the facilely designed Ti3C2Tx MXene-280 sensor is believed to contribute to developing future portable and selective sensing electronics at room temperature.

To evaluate carotid elasticity by using two-dimensional strain imaging (2DSI) in type 2 diabetes mellitus (T2DM) patients with nonalcoholic fatty liver disease (NAFLD). 98 patients with T2DM diagnosed in our hospital were selected. All the patients were without carotid plaque, which were proved by carotid ultrasonography. According to the fatty liver classification standard, patients were divided into three groups. There were 35 cases without NAFLD in group A, 33 cases with mild NAFLD in group B and 30 cases with moderate to severe NAFLD in group C. By using two-dimensional and M-mode ultrasound to measure the left carotid intima-media thickness (IMT), common carotid arterial systolic diameter (Ds) and diastolic diameter (Dd). The systolic peak velocity was measured by spectral Doppler ultrasound. The systolic global peak circumferential strain (CS), early and late systolic global circumferential strain rate (CSr) were measured by 2DSI. The stiffness parameters β1 and β2 were calculated by M-mode ultrasound and 2DSI separately. Among three groups, the Ds, Dd and systolic peak velocity showed no significant difference (all P .05). In group C, IMT and β1 were obviously increased than those of groups A and B (all P .05). Compared groups A and B, there were no significant difference in IMT and β1 (all P.05). β2 was higher in groups B and C than those in group A, CS, CSr were lower in groups B and C than those in group A (both P .05). The carotid elasticity of T2DM patients with NAFLD can be evaluated by 2DSI.

Formaldehyde (HCHO) is a colorless and irritating volatile organic compound, which has been proven to be one of the raw materials that cause pathological building syndrome, as well as a major source of indoor environmental pollution. Long-term exposure of human body to formaldehyde will cause certain health risks, so it is of great practical significance to develop a fast and effective formaldehyde detection sensor. Tin dioxide (SnO2), an n-type semiconductor metal oxide with a specific bandgap (3.62 eV, at 300 K), has been widely used as efficient sensors material for hazardous gases detecting. Different ratios of Sm-doped SnO2 nanoparticles had been successfully prepared by a simple solvothermal route and used as sensing materials in this work. The sample structure, micromorphology, and ingredient were characterized by XRD, SEM, TEM, XPS, and other methods of formaldehyde gas-sensing characteristics were studied. The results shown the optimum compound ratio of Sm-doped SnO2 nanoparticles was 5.0 mol%, the optimal operating temperature was 160 °C, and the sensor shown high gas response, reliable stability and selectivity to formaldehyde. The sensor shown the outstanding gas-sensing performances to formaldehyde ascribed the average grain size of the Sm-doped SnO2 nanoparticles and the positive role of Sm. Besides, the possible gas-sensing mechanism of the prepared sensor to formaldehyde was analyzed in detail.

Background The intestinal microbiota and metabolites play an important role in human health and immunity. However, few studies have investigated the long-term effects of stachyose on the human intestinal microbiota and metabolism. Therefore, in this study, the feces of infants were transplanted into germ-free mice, and the effect of long-term stachyose intake on intestinal metabolism was examined by comparing the results of microbiome and metabolome analyses. Ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used to study the effects of stachyose intake on the metabolites and metabolic pathways of the transplanted human intestinal microbiota. Results We observed that stachyose significantly altered the composition of the intestinal microbiota and metabolites, up-regulated production of the metabolite taurocholic acid, down-regulated amino acid metabolism, and significantly regulated the metabolism of taurine and hydroxytaurine, pantothenate and coenzyme A (CoA) biosynthesis, and other signaling pathways. Conclusion These findings may provide a basis for elucidating the mechanism by which stachyose promotes host health. © 2020 Society of Chemical Industry.

To evaluate left atrial function in patients with triple-vessel disease (TVD) without myocardial infarction by real-time three-dimensional echocardiography (RT-3DE) and two-dimensional speckle tracking imaging (2D-STE).Sixty patients with coronary artery disease (CAD) without myocardial infarction were classified into two groups in accordance with the coronary angiography results: group B (all triple-vessel stenosis ≥ 50% and 75%) and group C (all triple-vessel stenosis ≥ 75%). Thirty healthy individuals were selected as group A. LA volume related parameters including left atrial maximum volume index (LAVImax), LA passive and active ejection fraction (LAPEF, LAAEF) and LA total ejection fraction (LATEF) were measured by RT-3DE. The global peak atrial longitudinal systolic strain (LASRs), early and late diastolic LA strain (LASRe and LASRa) rates were measured by 2D-STE.We found statistically significant differences between 2D-STE and RT-3DE related parameters of these three groups. Furthermore, in groups B and C, N-terminal fragment brain natriuretic peptides (NT-pro-BNP) and left ventricular end-diastolic pressure (LVEDP) were found to be significantly correlated with LASRs and LASRa. And NT-pro-BNP had a moderate correlation with LVEDP.2D-STE and RT-3DE can assess the LA function in patients with TVD without myocardial infarction. And LA strain values may provide additional information for predicting increased LVEDP and NT-pro-BNP.

The noble metal nanoparticles have attracted attention due to their excellent catalytic performance for CO oxidation at low temperatures. M-CeO

In order to improve the survival rate of probiotics and produce probiotic goat milk from fermented goat milk of Lactobacillus casei L61 by spray drying. Spray drying has been applied to large-scale industrial production of milk powder due to its high efficiency and low cost. However, high temperatures in spray drying can result in the loss of large numbers of probiotic.The purpose of this paper is to study the effects of eight thermal protectants including skim milk, sucrose, glucose, β-cyclodextrin, gelatin, maltodextrin, glycerol, trehalose on the survival rate and viable counts of L.casei L61 after heat treatment by the single factor experiment. All protective agents have a positive effect on increasing the survival rate of L.casei L61 (pL.casei L61 were up to the maximum of 10.94%, 1.13%, 3.04%, 0.21%, 6.97%, 0.075, 4.71% and 0.29%, while the additions of skim milk, sucrose, glucose, β-cyclodextrin, gelatin, maltodextrin, glycerol, trehalose were 20mg/L, 10%, 7%, 15%, 1.5%, 3%, 8mL/L, 10%, respectively; the viable counts after heat treatment are 19.69, 0.81, 1.78, 0.455, 12.2, 0.12, 2.75, 0.435(×106CFU/mL), respectively. This paper provides technical a reference for the development of probiotic goat milk powder.

Freeze drying has been well applied in the preparation of high-efficiency probiotic powders. However, the process is generally accompanied by probiotic viability deficiency, which is the bottleneck for further application. To improve the viability of Bifidobacterium bifidum BB01 during freeze-drying, we optimized the cryoprotectant of B. bifidum BB01 by response surface methodology (RSM) with a Central Composite Design (CCD). In this study, two values of B. bifidum BB01 with different protectant factors were investigated, including freeze-drying survival rate and the viable counts of per unit weight of freeze-dried powder. The optimized cryoprotectants were obtained as follows: glycine of 5.5%, sodium bicarbonate of 0.8%, xylo-oligosaccharides of 7%, arginine of 4.5% and skim milk of 25%. The survival rate and the viable counts of per unit weight of powder were 90.37 ± 1.9% and (2.78 ± 0.13) × 1011cfu·g-1, respectively, both close to the predicted value (88.58% and 2.71 × 1011 cfu·g-1). Our research demonstrated that RSM was successful in optimizing composite cryoprotectant for freeze-dried powder of B. bifidum which can as well protect the probiotic cells.

AIM Using three-dimensional ultrasound speckle tracking echocardiography (3D-STE) to evaluate left ventricular (LV) function in patients with triple vessel coronary artery disease(TVD) without myocardial infarction. METHODS Sixty patients with TVD without myocardial infarction were divided into two groups according to the results of coronary angiography. Group B (n=31)：50%≤the stenosis rate of all triple vessel coronary artery＜75%; Group C (n=29)：the stenosis rate of all triple vessel coronary artery≥75%. Thirty healthy subjects were recruited as the group A. We measured LV end-diastolic and end-systolic volume (LVEDV, LVESV) and LV ejection fraction (LVEF) using real-time dynamic three-dimensional echocardiography. The 3D-STE parameters of LV included global longitudinal strain (GLS), global area strain (GAS), global radial strain (GRS) and global circumferential strain (GCS). The correlation between 3D-STE parameters and NT-proBNP were analyzed by Pearson linear correlation analysis. RESULTS In group C, LVEDV and LVESV were significantly increased (all P＜0.05), while LVEF, GLS, GRS, GCS and GAS were significantly decreased compared with groups A and B (all P＜0.05). In groups A and B, there were no statistical differences in LVEDV, LVESV and LVEF. However, GLS, GCS and GAS were lower in group B than in group A (all P＜0.05). The correlation analysis showed a negative correlation between the absolute values of GLS, GRS, GCS, GAS and NT-proBNP in group C (r=-0.866、-0.587、-0.428、-0.600，P＜0.001、P=0.001、P=0.020、P=0.010). CONCLUSIONS Our study shows that 3D-STE can evaluate the LV function in patients with triple vessel coronary artery disease without myocardial infarction through multiple strain parameters.

The excessive use of imidacloprid in agricultural production leads to a large number of residues that seriously threaten human health. Therefore, the detection of imidacloprid has become very important. But how to quantitatively detect imidacloprid at ultra-low levels is the main challenges. In this work, trimetallic metal-organic frameworks Fe, Co, Ni-MOF (FCN-MOF) is in situ prepared on nickel foam (NF) and then used to make an electrochemical sensor in the detection of imidacloprid. FCN-MOF exhibits the characteristics of ultra-micro concentration detection for imidacloprid with high specific surface area and rich active metal centers. The high conductivity and 3D skeleton structure of the NF electrode enhance the contact site with imidacloprid and promote the transmission of electrons efficiently. All results show that the prepared electrochemical sensor has the advantages of ultra-low detection limits (0.1 pM), wide linear detection ranges (1–5 × 107 pM) and good sensitivity (132.91 μA pM‒1 cm‒2), as well as good reproducibility, excellent anti-interference ability, and fantastic stability. Meanwhile, the electrochemical sensor is used to determine imidacloprid in lettuce, tomato, and cucumber samples with excellent recovery (90%–102.7%). The novel electrochemical sensor is successfully applied to the ultra-micro detection of imidacloprid in vegetables, which provides a new way for the efficient monitoring of imidacloprid in agriculture.

Fast and effective detection of harmful gases is crucial criterion for the current development of gas sensors. In this paper, a novel n-butanol gas sensor using Al-doped CdIn2O4 nanofibers (ACO NFs) is synthesized by an electrospinning method. The different morphologies of the as-prepared ACO NFs are controlled by doping different Al contents. Systematic characterizations demonstrate that the doping of Al to CdIn2O4 NFs would enhance the reaction activities between the gas and sensing materials, such as generating large amounts of adsorbed oxygen and improving the specific surface area of sensing materials. The results show that the detection limit of all prepared sensors for n-butanol is sub-ppm, and less than 250 ppb. The optimal Al-doped CdIn2O4 (5.0% Al/Cd molar ratio) based gas sensor results in 3.32-fold enhancement in gas response to 200 ppm n-butanol at an operating temperature of 300 °C and exhibits excellent long-term stability compared with the pure CdIn2O4. Hence, ACO NFs can be regarded as a promising sensing material for low-concentration n-butanol gas detecting. Also, the mechanisms for improving the sensing performance of ACO NFs based gas sensor are proposed.

Early-life antibiotic exposure can increase the risks for immune and metabolic disease development. However, research on the effect of stachyose on the antibiotic-destroyed microbiota is still lacking. In this study, we investigated the effect of stachyose on the gut flora of weaned mice and evaluated whether stachyose can improve the intestinal flora in early life after antibiotic consumption. We found that stachyose increased the abundance of Akkermansia in the intestinal microbiota, increased acetic and propionic acid levels, ameliorated LPS-mediated inflammation through the NF-κB pathway, and increased occludin and ZO-1 expression in penicillin-treated mice. However, when the intestinal flora was severely disrupted, stachyose could not significantly reduce intestinal inflammation or increase occludin and ZO-1 expression levels. These findings suggest that dietary supplementation with stachyose may reduce the negative impacts of antibiotic treatment, laying a foundation for the use of prebiotics to prevent and treat antibiotic-mediated infections.

In this study, a D-optimal mixture design was adopted to evaluate the effect of different excipient combinations of xylitol, erythritol, mannitol, sodium alginate, and microcrystalline cellulose on the quality of probiotic goat milk tablets. Four indicators, namely, viable cell counts, friability, hardness, and sensory evaluation, were used to determine the optimal formulation with xylitol of 9.00%, erythritol of 2.85%, mannitol of 3.00%, microcrystalline cellulose of 0.15%, goat milk powder of 84.90%, and mixed bacteria powder of 0.10%, which can well protect probiotics. In addition, the viability of the probiotics was measured during the storage and in the gastrointestinal tract. The storage stability test showed that the viable counts of probiotics goat milk tablets could still remain at 106 CFU/g after storage at room temperature (25 °C) for 210 days. The simulation experiment in vitro verified that probiotics can tolerate gastrointestinal fluids, reach the intestine smoothly under the protection of the goat milk tablet formula, and exert its probiotic effect. The research demonstrates that the optimal mixture design is reliable and the tablets exhibit high viable counts, have good sensory characteristics, and offer ideal stability, which provides a basis for the development of industrial production of probiotic goat milk tablets.