Manipulation of Weyl Points in Reciprocal and Nonreciprocal Mechanical Lattices.

We introduce feedback-measurement technologies to achieve flexible control of Weyl points and conduct the first experimental demonstration of Weyl type I-II transition in mechanical systems. We demonstrate that non-Hermiticity can expand the Fermi arc surface states from connecting Weyl points to Weyl rings, and lead to a localization transition of edge states influenced by the interplay between band topology and the non-Hermitian skin effect. Our findings offer valuable insights into the design and manipulation of Weyl points in mechanical systems, providing a promising avenue for manipulating topological modes in non-Hermitian systems.

[Dietary exposure assessment of deoxynivalenol and its acetylate & derivatives in wheat flour in Shanghai].

OBJECTIVE: To assess the dietary exposure of Shanghai residents to a compound of deoxynivalenol (DON) and its acetylated derivatives, 3-acetyl-deoxynivalenol (3-Ac-DON) and 15-acetyl-deoxynivalenol (15-Ac-DON) through wheat flour. METHODS: DON, 3-Ac-DON and 15-Ac-DON in wheat flour collected from 2011 to 2013 were respectively analyzed by high performance liquid chromatography tandem mass spectrometry. (HPLC-MS/MS) method and the total content of the compound was calculated. Dietary intake assessments of the compound through wheat flour were carried out in combination of wheat flour consumption data of Shanghai residents with the compound content data using both the point estimate method and the probabilistic assessment method. Group provisional maximum tolerable daily intake(PMTDI, 1 jg/(kg BW- d) )of the compound was used to assess the risk of the exposure. RESULTS: (1) At the mean and 50th percentile consumption level of wheat flour, the dietary exposure of people to the compound accounted for 18%-83% of PMTDI based on different content levels (mean and the 50th, 75th, 90th and 95th percentiles) of the compound. At the 95th percentile consumption level of wheat flour, the exposure was 1.08-2.55 times higher than PMTDI based on different toxin levels (mean and the 50th, 75th, 90th and 95th percentiles). (2) 89.99% of total Shanghai residents, 87.00% of Shanghai wheat flour consumers, and 76.55% of Shanghai residents under 15 years old had a daily exposure to the compound lower than PMTDI. CONCLUSION: The dietary exposure of Shanghai residents to the compound of DON, 3-Ac-DON and 15-Ac-DON increased along with the increase of wheat flour consumption. Most of the residents were safe through wheat flour consumption, but still 10.01% of the population was at risk, and residents under 15 years old were a high-risk group for the compound exposure.

Dietary exposure to aluminium from wheat flour and puffed products of residents in Shanghai, China.

A dietary survey of 3431 residents was conducted by a 24-h dietary recall method in Shanghai, China, quarterly from September 2013 to September 2014. A total of 400 food samples were tested for aluminium concentration, including wheat flour and puffed products from 2011 to 2013. Probabilistic analysis was used to estimate the dietary exposure to aluminium from wheat and puffed products. The means of dietary aluminium exposure for children (2-6 years old), juveniles (7-17 years old), adults (18-65 years old) and seniors (over 65 years old) were 1.88, 0.94, 0.44 and 0.42 mg kg(-1) body weight (bw) week(-1) respectively, with a population average of 0.51 mg kg(-1) bw week(-1). The proportions of those who had aluminium exposure from wheat and puffed products lower than the provisional tolerable weekly intake (PTWI) were 77%, 90%, 97%, and 97% respectively from children to seniors. We estimated that the proportions of people at risk would decrease by 13%, 6%, 2% and 2% respectively under the new China National Standards - GB 2760-2014 National Food Safety for Standards for using food additives. The results indicated that aluminium from wheat flour and puffed products is unlikely to cause adverse health effects in the general population in Shanghai; however, children were at a higher risk of excess aluminium exposure. Significant improvements in reducing the dietary exposure to aluminium are expected in the population, especially for children after the implementation of GB 2760-2014.

[Risk assessment of fluoride exposure to pork and offal products of pigs in Shanghai City].

OBJECTIVE: To estimate the exposure of fluoride to pork and offal products of pigs and assess their health risks in Shanghai residents. METHODS: Conducting a dietary survey in 1630 residents cluster sampled from four districts in Shanghai. Detecting fluoride in 872 pork and offal samples, and using Monte Carlo method to estimate the chronic daily intake (CDI) and hazard quotient (HQ) of fluoride in Shanghai residents caused by eating pork and offal products of pigs. RESULT: The CDI of fluoride is less than the tolerable daily intake (TDI), and the HQ is less than 1. The intake of pork and offal product is less in elder people than young people (P < 0.05), and that is less in female than male (P < 0.05). The fluoride content in offal is higher than that in pork (P < 0.05), the fluoride in kidney (P < 0.05) and liver (P < 0.05) is higher than that in other viscera. CONCLUSION: The intake of fluoride from pork and offal products in Shanghai residents is lower than the TDI of fluoride and not reaching the risk level of fluoride causing dental fluorosis, unhealthy of bone and osteofluorosis.