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991.
This work aimed to determine the changes in the morphology, complexation degree, the structural, thermal, and rheological properties of starch–fatty acid complexes during steam cooking. In this study, wheat starch with certain water and palmitic acid contents were steamed for 0.5, 1, 1.5, 2, and 2.5 h. The complexing index (CI) first decreased and then progressively increased with the prolonging of steam cooking time. The decrease in CI was associated with the decomposition of the complex layer formed on the granule surface at 0.5 h of steam cooking. The interaction between wheat starch and palmitic acid led to the change of starch crystal type. Prolonging treatment time promoted thermal stability and structural order degree. The type I and IIa complexes reached saturation and fatty acids in the interstitial space between helices increased with excessive treatment times. Rheological behavior analysis showed that the viscoelasticity and deformation degree of samples decreased and increased, respectively, with increasing steam cooking time. Results showed that the thermostability and order degree of the complex layer were lower than those of samples with long treatment times and complexing was effective during steam cooking.

The present paper introduces the formation and characteristics of wheat starch–palmitic acid complexes during long-term steam cooking.  相似文献   
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Effective edge oxidation of graphene with high structural integrity is highly desirable yet technically challenging for most practical applications. In this work, we have developed a green and facile strategy to obtain edge-oxidized graphene with good dispersion stability and high electrical conductivity by exploiting high edge reactivity of highly conductive multi-layer graphene and oxidizing radicals (SO4˙) generated from sodium persulfate (Na2S2O8) with ferrous ion (Fe2+) activation. Owing to high structural integrity of pristine graphene and effective edge oxidation, the obtained edge-oxidized graphene exhibited excellent dispersion stability and satisfactory electrical conductivity (i.e. ≥240 S cm−1). Moreover, the oxidation degree of pristine graphene can be well controlled by adjusting treatment time. The obtained edge-oxidized graphene is expected to find a variety of applications in many fields of anti-static films, energy storage materials, flexible sensors and high-performance nanocomposites.

A green and facile strategy is represented to obtain edge-oxidized graphene by exploiting sulfate radicals generated from Na2S2O8 with Fe2+ activation.  相似文献   
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Cannabis, also known as marijuana, is one of the most commonly used substances for medical and recreational purposes globally. With the trend of global legalization of medical use of cannabis and even the recreational use, the prevalence of recreational use of cannabis has increased markedly over the past few years. Correspondingly, the potential health concerns related to cannabis consumption have also increased. Therefore, it is necessary for oral healthcare providers to understand the effects of cannabis use on oral health. This review briefly summarizes the components of cannabis, biologic activities on tissues, and mechanisms of action in human cells and tissues. Oral tissue expression of cannabinoid receptors and the potential association of cannabis to oral diseases are also examined. The goals of this review are to (1) elaborate the basic biology and physiology of cannabis in human oral tissues, and (2) provide a better understanding the effects of its use and abuse on oral health. Due to insufficient information, more well‐designed studies should be conducted. It is urgent to include cannabis usage into dental patient health records.  相似文献   
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Cao  Xiaofei  Wu  Junbei  Fang  Yin  Ding  Zhengnian  Qi  Tao 《Clinical oral investigations》2020,24(12):4335-4342
Objective

In this study, we aimed to assess the feasibility of fiberoptic intubation (FOI), using a new, self-designed, “tongue root holder” device, in combination with the jaw thrust maneuver.

Methods

Three hundred patients undergoing elective surgery requiring orotracheal intubation were enrolled. Patients presented at least one or more risk factors for difficult airway. The patients were randomly allocated at a 1:1 ratio to one of two groups: group L, FOI with tongue root holder, or group C, standard FOI. Orotracheal FOI was performed after commencement of anesthesia. The jaw thrust maneuver was applied in both groups to facilitate advancement of the fiberoptic bronchoscope. The primary endpoint was the feasibility of FOI. The secondary endpoints were number of attempts, time to intubation, and airway clearance at the soft palate and epiglottis levels.

Results

The FOI was achieved in all 150 patients in group L, significantly higher than that in group C (100% vs 95.3%; P = 0.015). Less attempts of intubation were made in group L (P = 0.039). Mean time to successful intubation on the first attempt was shorter in group L (P < 0.001). The mean times to view the vocal cord and carina were also shorter in group L (P = 0.011 and P < 0.001, respectively). Airway clearance was better in group L at both the soft palate and the glottis levels (P = 0.010 and P = 0.038, respectively).

Conclusions

This study shows that FOI is feasible with the newly introduced, self-designed, “tongue root holder” device, when combined with the jaw thrust maneuver in patients with risk factors for difficult airway. The device also provides better airway clearance, less intubation attempts, and shorter time to intubation at first attempt.

Clinical relevance

Fiberoptic bronchoscope has been the gold standard for routine management of difficult airway. A technique to open the airway is introduced to reduce the incidence rate of upper airway obstruction.

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