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ABSTRACT: Oxidative stress is a crucial factor in the age-related decline in physiological, genomic, metabolic, and immunological functions. We screened Lactiplantibacillus plantarum JS19, which has been shown to possess therapeutic properties in mice with ulcerative colitis. In this study, L. plantarum JS19 used as the adjunct starter culture in fermented goat milk (LAF) was employed to alleviate d-galactose-induced aging and regulate intestinal flora in an aging mouse model. The oral administration of LAF effectively improved the health of spleen and kidney in mice, while mitigating the hepatocyte and oxidative damage induced by d-galactose. Additionally, LAF alleviated d-galactose-induced dysbiosis of the intestinal flora by reducing the abundance of harmful bacteria Desulfovibrio and Helicobacter, while greatly promoting the growth of beneficial Rikenellaceae_RC9_gut_group and Eubacterium. Biomarker 5-hydroxyindole-3-acetic acid was found to be positively linked with those harmful bacteria, whereas bio-active metabolites were strongly correlated with the beneficial genus. These observations suggest that LAF possesses the capability to mitigate the effects of d-galactose-induced aging in a mouse model through the regulation of oxidative stress, the gut microbiota composition, and levels of fecal metabolites. Consequently, these findings shed light on the potential of LAF as a functional food with antiaging properties.

Abstract Background Iron deficiency anemia (IDA) is a common health problem worldwide. The objective of this study was to noninvasively and quantitatively evaluate early changes in left ventricular systolic function in patients with IDA using the left ventricular press–strain loop (LV-PSL). Methods Sixty-two patients with IDA were selected and divided into two groups based on hemoglobin (Hb) concentration: Group B with Hb > 9 g/dL and group C with 6 g/dL

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.

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.

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.

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.

Enterotoxigenic Escherichia coli (ETEC) is an important pathogen causing diarrhea in humans. Finding natural, safe and effective functional ingredients to replace antibiotics is an important direction for preventing and treating E. coli infection and protecting intestinal health. However, it is unknown whether stachyose promotes the proliferation of probiotics and thus inhibits ETEC infection. Here, we investigated whether stachyose improves the gut microbiota of ETEC-infected mice and induces effects in early postnatal life. Stachyose promoted the proliferation of A. muciniphila and Bifidobacterium, increased short chain fatty acids (SCFAs) levels, increased the expression of tight junction proteins (occludin and ZO-1), increased SIgA and albumin levels, and reduced the level of lipopolysaccharide (LPS), IL-1, 6, 17 and TNF-α. After antibiotic-induced ablation, the resistance of the intestinal microbiota of the ETEC-infected mice to bacteria was significantly reduced, and the level of inflammation was increased, the SIgA and albumin levels decreased significantly, showed the intestinal microbiota plays an important role in maintaining immune resistance. Stachyose enabled partial microbiota recovery and protection after ETEC infection.

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 (p<0.05). The results indicated that the survival rates of L.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. [ABSTRACT FROM AUTHOR]

Antioxidant peptides are widely used in many fields due to their biological activities such as anti-cancer, anti-induction and anti-aging. However, little information is available concerning the peptides production by enzymatic hydrolysis of casein from goat milk. In this study, response surface methodology (RSM) was applied to optimize the conditions of the hydrolysis of goat milk casein by proteases (alcalase in combination with papain) to increase the antioxidant activity of the peptides. The results showed that the optimal hydrolysis conditions were as follows: temperature of 61°C, enzyme/substrate ratio (E/S) of 5.6%, and protease ratio (papain: alcalase) of 1.8:1. Under the optimal conditions, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity significantly increased (1.17 folds compared to un-optimized conditions). Furthermore, Fe2+ chelating ability and superoxide radical scavenging activity increased 1.02 folds and 1.14 folds, respectively. The antioxidant activity was significantly improved after optimization and provided a basis for the study of the antioxidant effects of hydrolysed goat milk casein. [ABSTRACT FROM AUTHOR]

This correction notice from BioMedical Engineering OnLine acknowledges that the original publication of an article on left ventricular systolic function in patients with iron deficiency anemia was missing the affiliation of Author Kefeng Li from the School of Applied Sciences at Macao Polytechnic University. The correction has been made to include this information in the updated article. The correction notice was reported by multiple authors involved in the study. [Extracted from the article]

Background: Iron deficiency anemia (IDA) is a common health problem worldwide. The objective of this study was to noninvasively and quantitatively evaluate early changes in left ventricular systolic function in patients with IDA using the left ventricular press–strain loop (LV-PSL). Methods: Sixty-two patients with IDA were selected and divided into two groups based on hemoglobin (Hb) concentration: Group B with Hb > 9 g/dL and group C with 6 g/dL < Hb < 9 g/dL. Thirty-three healthy individuals were used as the control (Group A). The global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global waste work (GWW), global work efficiency (GWE) were derived using LV-PSL analysis. Receiver operating characteristic (ROC) curves were constructed for MW parameters to detect abnormal left ventricular systolic function in IDA patients. Results: Compared to group A, GWI and GCW were reduced in group B (both P < 0.01). Compared with groups B and A, GLS, GWI, GCW and GWE, and E/A were all diminished, and GWW, LVEDV, LVESV, and E/mean e' were all increased in group C (all P < 0.01). GLS was positively correlated with GWI, GCW, and GWE (r = 0.679, 0.681, and 0.447, all P < 0.01), and negatively associated with GWW (r = − 0.411, all P < 0.01). For GWI, area under the ROC curve (AUROC) was 0.783. The optimal GWI threshold for detecting abnormal LV systolic function in IDA was1763 mmHg%, with sensitivity of 0.71 and specificity of 0.78. Conclusions: LV-PSL allows noninvasive quantitative assessment of early impaired LV systolic function in IDA patients with preserved LV ejection fraction, and GWI has high sensitivity and specificity compared with other parameters. [ABSTRACT FROM AUTHOR]

In this study, substrates of glass were used for the deposition of transparent nanostructured thin layers of Titanium dioxide (TiO2) using a spin-coating system, and the solution was processed by sol-gel process. TiO2 sol and films were prepared with TTIP, hydrochloric acid, DI water, and ethanol. Here is the current work, these thin films were analyzed for various annealing treatments at 300°C, 400°C, 500°C. The various attributes of films such as structural are described by X-ray diffraction (XRD) and RAMAN spectroscopy, morphology, and topography are studied by SEM and AFM, and optical properties are examined by UV-Vis spectroscopy. The direct energy bandgap estimated for the TiO2 films is 3.65ev, 3.71ev, and 3.75ev after heating at 300°C-400°C-500°C. The initial crystalline phase (anatase) of TiO2 shows up after 400°C for the four layers which are confirmed by XRD and RAMAN studies. At high temperatures, brookite and rutile crystalline phases are also found with the anatase phase. The attained films are translucent in the wavelength range between 380-700nm and blurred in the 100-380nm range. [ABSTRACT FROM AUTHOR]

Herein, we report our work on ZnO/CuO mesoporous nanocomposite synthesized via a simplistic and cost-effective Co-precipitation technique. The heterostructure was examined for structural, morphological, optical, and gas-sensing properties for pure ZnO, CuO and ZnO/CuO nanocomposite at room temperature. The Bandgap, refractive index and transmittance percentage were determined for the as-prepared samples. The gas sensing study has been systematically introduced to report how the nanocomposite can enhance the sensing capabilities. The nanostructured materials offer good point defects (oxygen vacancies) and high surface area that attributes stronger gas adsorption via active sites for enhanced gas sensing performance. The heterojunction in the n-ZnO/p-CuO nanocomposite gas sensor has exhibited strong sensing performance at low concentrations of n-butanol (5–20 ppm) with a sensor response of 247% and a quick response of 19 s and recovery time of 11 s, which were explained in terms of the hole accumulation layer (HAL) and the quantum confinement effects in the nanocomposite. The ability of sensing a low n-butanol concentration at room temperature provides a feasible path for practical gas sensing application of these ZnO/CuO nanocomposites. [ABSTRACT FROM AUTHOR]

At present, there are still few gas sensors for detecting n‐butanol at room temperature. It is worth noting that detecting target gas at room temperature is beneficial to reduce energy consumption and prolong the lifetime of sensors. In this work, different molar ratios Au nanoparticles modified SnO2 derived from Sn‐MOF hollow cubes (Au‐SnO2) are synthesized by the coprecipitation method. The Au‐SnO2 has higher specific surface area than pure SnO2, which is conducive to improving gas sensing. The 0.7% Au‐SnO2 exhibit excellent sensing performances of 240% toward 100 ppm n‐butanol and the actual detection interval is 200 ppb–500 ppm under the room temperature. Meanwhile, DFT calculations reveal that Au‐SnO2 gas sensor has wonderful selectivity to n‐butanol at room temperature. The enhancement of n‐butanol sensing performance is also related to the "catalytic sensitization" effect and the "electron sensitization" effect triggered driven by Au NPs. It is hoped this Au‐SnO2 sensing material with such great gas response, selectivity and low detection limit will help detect n‐butanol at room temperature to lower energy consumption. [ABSTRACT FROM AUTHOR]

Ammonia monitoring in our daily life is significant. In this work, Ti3C2Tx/ZnO materials were prepared by hydrothermal method. The results of XRD, SEM, TEM, and XPS analyses demonstrated the successful preparation of the Ti3C2Tx/ZnO composite. Ti3C2Tx/ZnO (3:1) material exhibited the best morphology as ZnO grows evenly on it as ultrathin nanosheets. The gas sensing performance of Ti3C2Tx, ZnO, and Ti3C2Tx/ZnO (1:1, 2:1, 3:1, and 5:1) materials were studied. The Ti3C2Tx/ZnO (3:1) sensor has an excellent response to 50 ppm ammonia at a low operating temperature (∼28 °C), and the value of response is 196%, which is the highest response in this work. Furthermore, it was found that Ti3C2Tx/ZnO (3:1) detects ammonia selectively against other volatile organic compounds at a low operating temperature (∼28 °C). The actual lowest detection ability was measured at 1 ppm, and the corresponding response is 14%. The ultra-thin ZnO nanosheets on the Ti3C2Tx MXene and the p–n heterojunctions in Ti3C2Tx/ZnO (3:1) are designed to achieve better ammonia sensing performance. This paper provided a route to enhance the p-type characteristic of Ti3C2Tx MXene, which is meaningful to Ti3C2Tx MXene application at a low operating temperature in the future. [ABSTRACT FROM AUTHOR]

Purpose: Using shear wave elastography (SWE) to assess carotid elasticity in the type 2 diabetes mellitus (T2DM) patients with non-alcoholic fatty liver disease (NAFLD). Methods: There were 98 patients diagnosed T2DM in our hospital, including 35 cases without NAFLD (group A), 33 cases with mild NAFLD (group B), and 30 cases with moderate to severe NAFLD (group C) according to the classification standard of fatty liver. There was no plaque by carotid ultrasound in all the selected patients. The left carotid intima-media thickness (IMT), standard carotid arterial systolic diameter (Ds), standard carotid arterial diastolic diameter (Dd), and systolic peak velocity (PSV) were measured by routine two-dimensional and M-mode ultrasound, and the stiffness coefficient (β) is obtained by calculation. Shear wave elastography (SWE) was used to measure the anterior wall of the left carotid artery values of longitudinal elastic modulus, including the mean values of mean elastic modulus (MEmean), the maximum elastic modulus (MEmax), and minimum elastic modulus (MEmin) at the end of diastole. Results: There was no significant difference in Ds, Dd, and PSV among the groups (all p > 0.05). In group C, IMT, β, MEmean, MEmax, and MEmin increased significantly compared with groups A and B (all p < 0.05). Compared with group A, MEmean, MEmax, and MEmin increased in group B (all p < 0.05), while IMT and β were no significant difference (both p > 0.05). Conclusion: SWE can quantitatively evaluate the carotid elasticity of the T2DM patients with NAFLD. [ABSTRACT FROM AUTHOR]

As a macrolide antibiotic, erythromycin is often used to treat bacterial infections in animal husbandry, but excessive use of erythromycin will make its residue in the animal and subsequently enter the human body through consumption, furthermore causing a different degree of damage to human health. It is quite essential to develop a fast and precise quantitative detection manner for erythromycin. In this study, we use arginine as a functional monomer and erythromycin as a template molecule to electro-polymerize a layer of molecularly imprinted polymer film on the surface of a glassy carbon electrode, and then use it as a recognition element to achieve quantitative erythromycin monitoring. The linear detection range of the prepared electrochemical sensor is from 3 nM to 1600 µM, the lowest detection limit (S/N = 3) is 2.01 nM, and the sensitivity is 57,300 µA cm−2 µM−1. The selectivity, reproducibility, and stability of the electrochemical sensor are satisfactory. At the same time, it can monitor whether honey contains erythromycin and its concentration, the recovery rate from 96.4 to 104.2%. After a series of performance tests, the results indicated that the Arg-MIP/GCE sensor has the potential to be applied in the measurement of erythromycin, which exists in food and agro-products. [ABSTRACT FROM AUTHOR]

Objective: 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). Methods: 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. Results: 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. Conclusions: 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. [ABSTRACT FROM AUTHOR]

Two-dimensional nanomaterials have exhibited considerable potential for gas sensing applications in recent years owing to their unique physical and chemical properties such as a large surface-to-volume ratio, abundant edge sites, versatile surface chemistry, etc. Herein, we demonstrate a two-dimensional Ti3C2TX MXene@TiO2/MoS2 nanocomposite gas sensor for ammonia detection at room temperature. MoS2 nanosheets are grown on an etched Ti3C2TX MXene surface by a hydrothermal method, and rectangular TiO2 particles are derived from Ti3C2TX MXene in the hydrothermal process. Meanwhile, nanocomposites with different Ti3C2TX MXene additions are also designed for gas sensing performance comparison. Such a novel hierarchical structure based gas sensor (MTM-0.2 sensor) exhibits fast response/recovery time and excellent long-term stability to ammonia. Meanwhile, outstanding selectivity to ammonia against triethylamine, trimethylamine, n-butanol, acetone, formaldehyde, and nitrogen dioxide at room temperature is also shown. The sensor shows 1.79-fold and 2.75-fold enhancement in the gas sensing response toward 100 ppm ammonia compared with the pristine Ti3C2TX MXene and MoS2 gas sensors, respectively. And its detection limit for ammonia is 500 ppb. The sensing mechanisms of the Ti3C2TX MXene@TiO2/MoS2 nanocomposites toward ammonia are attributed to the layered nanostructure, p–n heterojunction created at the interface of p-type Ti3C2TX MXene and n-type MoS2. Finally, density-functional theory (DFT) is performed to investigate the adsorption behavior and charge transfer of ammonia molecules on the surface of the nanocomposite. The synthesized Ti3C2TX MXene@TiO2/MoS2 nanocomposite can be regarded as a promising candidate for high-performance ammonia detection at room temperature. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

In this study, Lactobacillus L20 was screened by measuring the tolerance to the inorganic selenium and the resistance to the gastrointestinal fluid of 11 Lactobacillus preserved in the laboratory. Next, the selenium‐enriched L20 was produced into the corresponding selenium‐enriched L20 goat milk powder and milk tablet. The storage stability of the prepared powder and tablet were investigated by the accelerated test. The results indicated that the conversion rate of inorganic selenium of L20 was 87.65% and the viable count was 2.925 × 108 CFU/ml. The results of 16S rDNA homology of partial sequences of molecular characterization suggested that Lactobacillus L20 was Lactobacillus rhamnosus. More notably, the inactivation rate constants and the predicted shelf life of selenium‐enriched L. rhamnosus L20 goat milk powder and milk tablet were 2.40 × 10–4 and 1.90 × 10–4 day–1 and 285 and 406 days under 25°C, respectively, exhibiting a considerable long‐term stability. Practical applications: Selenium is one of the necessary microelements in human metabolism. Lactic acid bacteria can transform the inorganic selenium into organic selenium and selenium‐enriched Lactic acid bacteria can supply organic selenium and play its probiotic function. In this study, Lactobacillus rhamnosus L20 with strong selenium‐enriching ability was obtained and freeze‐dried powder was prepared. Selenium‐enriched probiotic goat milk powder and goat milk tablets were developed. The shelf life was predicted and prepared for selenium‐enriched probiotic powder. This work also provides a technical support for the subsequent industrialization of Se‐enriched probiotic goat milk powder and tablets. [ABSTRACT FROM AUTHOR]