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Objective： This study aimed to develop an ion chromatography-tandem mass spectrometry (IC-MS/MS) for the analysis of glyphosate and its metabolite amino methyl phosphoric acid (AMPA) residues in tea without derivatization. Methods： Tea samples were ultrasonically extracted with 20 mmol/L NaOH aqueous solution and cleaned up by dispersive solid-phase extraction (150 mg primary-secondary amine (PSA), 15 mg C18, 15 mg graphitized carbon black (GCB)). The samples were separated on an ion chromatographic column AS11-HC-4 μm (2 mm×250 mm) by using an isometric elution procedure of 35 mmol/L aqueous solution of sodium hydroxide as mobile phase. A multiple reactions monitoring (MRM) model was used to obtain the sensitivity of the method, and the isotopically labeled internal standards were applied in the calibration process. Good linearities and recoveries were obtained in the validation process. Results: The correlation coefficients R2 were 0.999 8 and 0.998 2, respectively. The detection limits of glyphosate and AMPA in tea were both 0.05 mg/kg, and the quantification limits were both 0.10 mg/kg. The average recoveries of glyphosate and AMPA were 61.2%～104.9% and 61.5%～83.2%, respectively with RSDs less than 20%. Conclusion: This method meets the requirements of green analytical chemistry and can be used for routine detection of glyphosate and aminomethylphosphoric acid residues in tea.

Primary thyroid adenoid cystic carcinoma (PTACC) is an extremely rare type of mucin-secreting adenocarcinoma. Currently, it is difficult to diagnose, and it lacks standard treatment protocols. We report the case of a 53-year-old female patient with PTACC who underwent additional intensity-modulated radiotherapy 1 month after surgical treatment with an uneventful course. No invasion or distant metastasis was detected at the 7-month follow-up after radiotherapy, and the prognosis was favorable. In this case, herein, we have summarized the diagnostic features of the disease and proposed that postoperative adjuvant radiotherapy can significantly improve the patient’s prognosis. Finally, we further confirmed the important role of radiotherapy in PTACC by reviewing relevant literature, which may provide clinicians with valuable treatment experience.

ObjectiveA high-throughput method for simultaneous determination of 67 herbicide residues in oilseeds and oils by liquid chromatography-tandem mass spectrometry combined with dispersive solid phase extraction was established.MethodsPeanut， soybean， rapeseed and their oil were extracted with 1% formic acid-acetonitrile， and then purified by ethylenediamine-N-propyl and anhydrous MgSO4 dispersed solid phase extraction. Methanol and 5 mmol/L ammonium acetate （containing 0.1% formic acid） were used as mobile phases for gradient elution. C18 column was used for separation， positive and negative ion mode of ESI ion source was used for simultaneous multi-reaction monitoring （MRM）. And matrix standard curve external standard method was used for quantification.ResultsUnder different substrates， the linear range of 67 herbicides was from 0.000 5 to 0.08 mg/L， the correlation coefficients （R2） were all above 0.992， and the limits of detection （LODs） were 0.005~0.02 mg/kg. The recoveries of three spiked levels （LOD， 2LOD and 10LOD） were between 62.3% and 118.1% with RSD （n=6） less than 15%.ConclusionThis method is stable， specific， sensitive and accurate， and can be used for qualitative and quantitative detection of herbicides in oilseeds and oils.

ObjectiveA qualitative and quantitative method was established for the simultaneous detection of 60 mycotoxins in nuts and dried fruits.MethodsPeanuts and raisins， two typical food substrates rich in fat and sugar， were pre-processed by QuEChERS technique （900 mg MgSO4， 150 mg PSA， 150 mg C18）， and analyzed by ultra-high performance liquid chromatography-high resolution mass spectrometry （UPLC-Orbitrap/MS） with full scan and data-dependent scanning （dd-MS2） mode. It was qualitatively determined by the retention time and accurate mass of mycotoxins， the chromatographic peak area was quantified， and the fragment ion information was used for confirmation.ResultsThe results showed that the pH value of the extraction solution significantly affected the dissociation state of mycotoxins， which in turn affected the recovery rate. The interference of components such as carbohydrates and lipids in the sample was effectively removed by QuEChERS purification， and the accuracy of qualitative and quantitative analysis was improved. A blank matrix-matched standard curve was used for calibration to reduce the matrix effect and meet the quantitative analysis requirements. The mycotoxins had a good linear relationship within their respective mass concentration ranges （correlation coefficient R2>0.95）， and the recoveries were 60%-120% with relative standard deviation less than 20%. The other seven mycotoxins with R2 less than 0.95 can be qualitatively analyzed.ConclusionCompared with the detection method based on triple quadrupole mass spectrometry， the high-resolution mass spectrometry method is easier to quantify， and there is no need to optimize the parent ion， product ion and collision energy for the target one by one，which can effectively reduce the difficulty and time consuming for multi-target analysis. The method has high sensitivity， accuracy and reliable results， and is suitable for the qualitative and quantitative analysis of 60 mycotoxins in nuts and dried fruits.

ObjectiveTo develop a method that can quickly determine the absolute content of boron in food by quantitative nuclear magnetic resonance （qNMR） analysis technology.MethodsThe signal area is directly proportional to the content of boron causing the peak under certain sample-acquired condition. Natural quartz NMR tubes （boron content 0.999 9. The LODs and the LOQs were 20 and 60 mg/kg， respectively. The recoveries ranged from 90.3% to 102.1%. The precision between days was 1.26%-1.61%.ConclusionThere are some good potential application prospects as for its simple pretreatment， quick measurement process， and accurate experimental result.

Existing studies that explore the relationship between business cycles and health remain debated. This study investigates the effects of economic fluctuation on obesity in the United States. Using the county-level unemployment rates from the Panel Study of Income Dynamics (PSID), we find that people are less likely to be obese during economic downturns. Particularly, a one percentage points increase in unemployment rates would lead to the chances of being obese reduced by 0.45% points. We further explore the underlying mechanisms of how business fluctuations affect obesity. We find that people tend to do more exercise and spend less on food expenditure during the economic downturns. [ABSTRACT FROM AUTHOR]