Feasibility study of prescribed burning for crop residues based on urban air quality assessment.

Open field burning of crop residue has been intentionally prohibited due to the undesired air pollution in urban regions. To better balance the urban environment and agricultural activity, this paper conducted a feasibility study of prescribed burning for crop residues based on air quality assessment in urban regions. Firstly, emission inventories were established using the top-down approach based on designed sub-regional fire as prescribed burning. Subsequently, the air qualities in urban regions were simulated by the coupled Weather Research and Forecasting Model-Community Multi-scale Air Quality Model (WRF-CMAQ) covering different sensitivity experiments. Finally, PM2.5 is selected as the main indicator of air quality, and the feasibility was assessed by controlling the factors influencing the diffusion of pollutants from prescribed burning, including burning ratio, meteorological factors (wind speed and direction), distance from burning area and burning duration. It is revealed that prescribed burning would achieve highly efficient disposal of crop residues under the premise of ensuring the air quality in urban regions by controlling the factors. Results in the study can be further exploited for designing burning scheme for crop residue, which is expected to promote a sustainable development of agriculture and urban environment.

The Role of Long Non-Coding RNAs in Thyroid Cancer.

Thyroid cancer, the most common endocrine malignancy, has become the most commonly diagnosed malignant solid tumor. Moreover, some cases have poor prognosis, and the survival period is only 3-5 months. Long noncoding RNAs (lncRNAs) are a group of functional RNA molecules more than 200 nucleotides in length that lack the ability to encode protein but participate in all aspects of gene regulation. Functionally, many lncRNAs play essential roles in epigenetic regulation at transcriptional and post-transcriptional levels via various molecular mechanisms. Recent studies have discovered important roles for lncRNAs during the complex process of carcinogenesis in thyroid cancer. In this review, we focus on lncRNAs dysregulated in thyroid cancer and summarize recently reported associations between lncRNAs and thyroid cancer in order to demonstrate the significant value of lncRNAs in diagnosis and treatment.

Coupling corona discharge for ambient extractive ionization mass spectrometry.

Unlike the extractive electrospray ionization (EESI) technique described elsewhere, a corona discharge instead of electrospray ionization has been utilized to charge a neutral solvent spray under ambient conditions for the generation of highly charged microdroplets, which impact a neutral sample plume for the extractive ionization of the analytes in raw samples without any sample pretreatment. Using the positive ion mode, molecular radical cations were easily generated for the detection of non-polar compounds (e.g., benzene, cyclohexane, etc.), while protonated molecular ions of polar compounds (e.g., acetonitrile, acetic ether) were readily produced for the detection. By dispensing the matrix in a relatively large space, this method tolerates highly complex matrices. For a given sample such as lily fragrances, more compounds were detected by the method established here than the EESI technique. An acceptable relative standard deviation (RSD 8.9%, n = 11) was obtained for the direct measurement of explosives (10 ppb) in waste water samples. The experimental data demonstrate that this method could simultaneously detect both polar and non-polar analytes with high sensitivity, showing promising applications for the rapid detection of a wide variety of compounds present in complex matrices.

Fast quantitative detection of cocaine in beverages using nanoextractive electrospray ionization tandem mass spectrometry.

Without any sample pretreatment, effervescent beverage fluids were manually sprayed into the primary ion plume created by using a nanoelectrospray ionization source for direct ionization, and the analyte ions of interest were guided into an ion trap mass spectrometer for tandem mass analysis. Functional ingredients (e.g., vitamins, taurine, and caffeine, etc.) and spiked impurity (e.g., cocaine) in various beverages, such as Red Bull energy drink, Coco-cola, and Pepsi samples were rapidly identified within 1.5 s. The limit of detection was found to be 7-15 fg (S/N = 3) for cocaine in different samples using the characteristic fragment (m/z 150) observed in the MS(3) experiments. Typical relative standard deviation and recovery of this method were 6.9%-8.6% and 104%-108% for direct analysis of three actual samples, showing that nanoextractive electrospray ionization tandem mass spectrometry is a useful technique for fast screening cocaine presence in beverages.