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To achieve accurate and highly sensitive determination of advanced glycation end products (AGEs) in baked food, a magnetic solid phase extraction (MSPE) technique based on magnetic covalent organic frameworks (COFs) material was established to achieve the selective and efficient enrichment of two major AGEs (i. e. Nε-carboxymethyl)lysine (CML) and Nε-(carboxyethyl) lysine (CEL)) in baked foods. The quantitative analysis of CML and CEL was conducted with high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method. Results showed that the synthesized magnetic COFs material showed big specific surface area and strong magnetism, which was suitable for MSPE. The optimum conditions of MSPE were as follows: the amount of adsorbent was 20 mg, the time of vortex extraction was 20 min, the elution solvent was 5% ammonia/methanol solution, the volume of elution solvent was 4 mL, the elution time was 15 min. The limits of detection of CML and CEL for the established method were 2.05 ng/mL and 2.31 ng/mL, respectively, while the limits of quantification were 6.83 ng/mL and 7.71 ng/mL, respectively. And intra-day and inter-day precisions were good (RSDintra-day ≤ 4.74%, RSDinter-day ≤ 5.38%). The recoveries of CML and CEL in typical food matrixes (i. e. biscuits and nuts) were in the range of 90.70% ~ 108.74% and 85.50% ~ 113.00%, respectively. Applying the analytical method established in this article to the determination of CML and CEL contents in 26 commercially available baked goods, it was found that the contents of CML and CEL in biscuits and pastries were in the range of (9.60 ± 0.16) ~ (78.10 ± 1.12) mg/kg, and (4.37 ± 0.23) ~ (26.70 ± 1.27) mg/kg, respectively; while the contents of CML and CEL in nuts were in the range of (6.49 ± 0.13) ~ (82.00 ± 0.98) mg/kg, and (6.65 ± 0.30) ~ (55.90 ± 0.67) mg/kg, respectively. The established method could effectively purify samples and significantly reduce matrix effect, and thus showed high accuracy for quantitative analysis. Furthermore, the synthesized magnetic COFs material could be recycled for 5 times, which was suitable for the determination of CML and CEL in baked food. [ABSTRACT FROM AUTHOR]

To investigate the air flow distribution in a lit cigarette during puffing, a device for measuring the air intakes through different sections of the cigarette was designed. The air intakes from the combustion cone, cigarette paper and filter during puffing were determined with the designed device. The air flow distribution in the cigarette during puffing and the net yield of mainstream smoke generated by the combustion cone were analyzed. The results showed that: 1) The air intakes from cigarette paper and filter during puffing were higher than those of an unlit cigarette, and the air intake from the combustion cone was lower than that of the unlit cigarette, and the filter ventilation rate of a cigarette with ventilation was higher than that of the unlit cigarette. 2) During the puffing of an unventilated cigarette, the air intake from the combustion cone linearly decreased with the increase of the remaining tobacco rod length, and the air intake from cigarette paper was directly proportional to the square of the remaining tobacco rod length. 3) There was a net yield of tobacco smoke during puffing, which was directly proportional to the air intake from the combustion cone, about 0.24 mL of net smoke was produced per milliliter air intake from the combustion cone. [ABSTRACT FROM AUTHOR]

To study the influences of puffing parameters on aerosol particle number and size from electrically heated tobacco products (eHTPs), a smoking cycle simulator-differential mobility spectrometer (SCS-DMS) was used for characterizing the particle number concentration and count median diameter (CMD) of the eHTP aerosol under different puffing parameters with the puffing volume of 35, 55, 75 mL, the puffing duration of 2, 3, 4 s, and the puffing interval of 30, 60 s respectively. The results showed that: 1) During single puff under square wave smoking regime, the particle number concentration of the aerosol from eHTP decreased and the count median diameter became smaller in real time with the proceeding of puffing. 2) The increases of puffing volume and puffing interval evidently increased particle number concentration of aerosol. When the puffing volume increased to 75 mL, the CMD of the aerosol was reduced. Puffing interval had no obvious effect on CMD. 3) Puffing durations slightly influenced the particle number concentration and CMD of the aerosol from eHTP. [ABSTRACT FROM AUTHOR]

To investigate the filtration effect of tobacco rod on smoke components in mainstream smoke, a method for analyzing the filtration by the residual tobacco section to smoke components was developed. A cigarette without its filter was lit without puffing and smouldered to the marked position of 15 mm to form a stable combustion cone, and following a puff by a linear smoking machine the residual tobacco section was cut into multiple subsections. The contents of 32 aerosol components filtered by each subsection were determined by GC-MS after extracting with dichloromethane. Six major smoke components, including nicotine, furfural, furfuryl alcohol, phenol, 4-methylphenol and indole, were selected as markers to reflect the filtration rules of tobacco section. The results showed that: 1) The filtration efficiencies of tobacco section to the target smoke components were between 12.0% and 73.6%. 2) The first subsection of 25 mm length adjacent to the combustion cone had stronger filtration to smoke components, which might be attributed to the condensation and adsorption of components in vapor phase. In comparison, the downstream subsection of tobacco rod had a weaker filtration effect, which mainly filtrated aerosol particles. This method is suitable to study the filtration rules of tobacco section to the 32 mainstream smoke components. [ABSTRACT FROM AUTHOR]

20 kinds of electrically heated cigarettes from 5 brands in the market were collected to characterize and compare the physical properties (number concentration, count median diameter and volume concentration) of total and puff-by-puff released aerosol. The results showed that the particle number concentration of the total aerosol released from the electrically heated cigarette was mainly in the order of 109/cm³, and the particle volume concentration was in the order of 105 μm³/cm³. The particle size distribution profiles of aerosol were unimodal or bimodal, and the count median diameter was mainly in the range of 30~60 nm. There were obvious differences in physical properties of total and puff-by-puff release of the aerosol from different brands of electrically heated cigarettes. The particle number concentration, count median diameter and volume concentration of the aerosol puff-by-puff released from the electrically heated cigarettes showed a certain degree of instability. [ABSTRACT FROM AUTHOR]

The La0.87Dy0.13Mn18&Fe&O3 (& = 0. 1,0. 2) polycrystalline sample was prepared vasa high-temperature solid-phase reaction method, and researched by XRD spectrum,M-T curves,M-H curves data. The results show that the samples have good single-phase, belong to the orthogonal structure, space group Pbnm;The Curee temperature TC of the two groups of sampe was around 130 K and 100 K respectively, and the interval of T80.87Dy0.13Mn0.9Fe0.103 has more potential as a magnetic refrigeration material than La0.87Dy0. i3-n0. sFe0.2O3. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of a new type of fixation tape for tracheal catheter in intensive care patients., Methods: A purposive sampling study was conducted. Ninety patients experienced oral tracheal intubation for mechanical ventilation, and admitted to respiratory intensive care unit (ICU) of the Second Affiliated Hospital of Nantong University from November 2015 to February 2017 were enrolled. All the patients were randomly (random number) divided into the control group and the observation group with 45 patients in each group. The patients in control group was treated with the traditional medical adhesive tape and fixation belt to fix endotracheal tube, while the patients in observation group was treated with a new type of tracheal catheter fixation tape. The fixation effect, skin complication rate, patient's comfort level, nursing workload and satisfaction were evaluated in both groups., Results: There were 6 patients with mild displacement, 2 patients with moderate displacement and 1 patient with severe displacement in the control group, while there was no catheter displacement or detachment occurred in the observation group, and the difference between the two groups was statistically significant (χ 2 = 2.944, P = 0.003). In the control group, there were 39 patients with facial skin redness, 6 patients with facial skin damage, 36 patients with neck skin redness, and 2 patients with neck skin damage. In the observation group, there were no facial skin complications and only 2 patients with neck skin redness, and the skin complication rate was significantly higher than that of the control group (facial skin: Z = 9.173, P = 0.000; neck skin: Z = 7.549, P = 0.000). Compared with the control group, the patients' comfort levels were significantly elevated in the observation group (the intolerance patients: 9 vs. 24, the extreme discomfort patients: 4 vs. 8, Z = 3.695, P = 0.000). The total changing times of the fixation belt and operating time for each change in the observation group were significantly decreased as compared with those of control group [changing times of the fixation belt (times): 1.89±0.77 vs. 3.86±1.18, operating time for each change (minutes): 10.31±1.47 vs. 15.78±1.89, both P < 0.01]. Nursing satisfaction in the observation group was significantly higher than that of the control group (100% vs. 33.3%, P < 0.01)., Conclusions: The new fixation tape for tracheal catheter could significantly reduce the catheter displacement and detachment rate, and decrease the incidence of facial skin injury. It is easy to learn and worth to generalize clinically.