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During the last decade, saliva has emerged as a potentially ideal diagnostic biofluid for noninvasive testing. In this paper, we present an automated, integrated platform useable by minimally trained personnel in the field for the diagnosis of respiratory diseases using human saliva as a sample specimen. In this platform, a saliva sample is loaded onto a disposable microfluidic chip containing all the necessary reagents and components required for saliva analysis. The chip is then inserted into the automated analyzer, the SDReader, where multiple potential protein biomarkers for respiratory diseases are measured simultaneously using a microsphere-based array via fluorescence sandwich immunoassays. The results are read optically, and the images are analyzed by a custom-designed algorithm. The fully automated assay requires as little as 10 μL of saliva sample, and the results are reported in 70 min. The performance of the platform was characterized by testing protein standard solutions, and the results were comparable to those from the 3.5-h lab bench assay that we have previously reported. The device was also deployed in two clinical environments where 273 human saliva samples collected from different subjects were successfully tested, demonstrating the device’s potential to assist clinicians with the diagnosis of respiratory diseases by providing timely protein biomarker profiling information. This platform, which combines non-invasive sample collection and fully automated analysis, can also be utilized in point-of-care diagnostics.

Quinoa is known for its rich nutrients and bioactive compounds. In order to elucidate the preliminary structural characteristics and biological activity of polysaccharides from quinoa (QPs), five crude polysaccharides (QPE50, QPE60, QPE70, QPE80 and QPE90) were successively fractionated by gradient ethanol, and their physicochemical properties, antioxidant and antidiabetic activities were analyzed. The results implied that their total sugar contents were 52.82%, 63.69%, 67.15%, 44.56%, and 41.01%, and their weight-average molecular weights were 13,785 Da, 6489 Da, 4732 Da, 3318 Da, and 1960 Da, respectively. Glucose was a predominantly monosaccharide in these QPs, which together in QPE50, QPE60, QPE70, QPE80, and QPE90, respectively, made up 94.37%, 87.92%, 92.21%, 100%, and 100% of the total polysaccharide. Congo red test showed that all five QPs contained triple-helix structure. The Fourier transform-infrared spectroscopy (FT-IR) and X-ray diffractometry (XRD) results suggest that the QPs form a semi-crystalline polymer constituted typical functional groups of polysaccharide including CO, CH and OH. The thermogravimetric analysis (TGA) of QPs showed that weight loss was at about 200 °C and 320 °C. The observation from scanning electron microscope (SEM) and atomic force microscope (AFM) image indicated that the morphology of QPs exhibited spherical shape. Antioxidant and antidiabetic assay exhibited that all five QPs samples had certain antioxidant and antidiabetic activities, and QPE90 showed the best antioxidant and antidiabetic activity. Overall, QPs present a promising natural source of food antioxidants and antidiabetic agents.

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Extremes in stratospheric abundances of HCl (record low) 1,2 , ClONO2 2 (record high), and ozone (record low) 1 were observed over southern hemisphere mid-latitudes following the 2020 Australian wildfires by satellite records spanning 15-20 years. These unprecedented changes suggest that wildfire aerosols pose a challenge to stratospheric chlorine and ozone depletion chemistry. Here we propose a wildfire smoke chemical mechanism linking data from the field and the laboratory, and test it by comparison of these extraordinary observations to model simulations. Aged wildfire aerosols likely contain a mix of oxidized organics 3-6 . Laboratory data indicate that HCl is extremely soluble in such species at relatively warm stratospheric temperatures 7-10 in mid-latitudes and Antarctic autumn. We find that the HCl solubility in oxidized organics, and associated enhancements in heterogeneous reaction rates in/on the aerosols, yield remarkable modelled changes in 2020 HCl, ClONO2, and HOCl abundances, in good agreement with observations. Our results indicate that wildfire smoke does not explain the record duration of the 2020 Antarctic ozone hole, but does yield an increase in its area, as well as 3-5% depletion of southern mid-latitude total column ozone. These findings increase concern that more frequent and intense wildfires could delay ozone recovery in a warming world.Massive wildfires in Australia during austral summer of 2019-2020 (December-January) produced pyrocumulonimbus (pyroCb) towers that released about 0.9 Tg of wildfire smoke into the stratosphere 11,12 . Wildfires are also sometimes denoted as bushfires, wildland fires, and forest fires; here we refer to them as wildfires. Wildfire smoke can be expected to be primarily composed of organic material, but its stratospheric chemistry is virtually unknown.Airborne mass spectrometry data 13,14,15 showed that carbonaceous compounds were also frequently present in about 30-40% of individual particles in the background northern hemisphere tropopause and lowermost stratosphere region.The carbonaceous fraction was largely internally mixed with sulfate (i.e., both