Preference-Aware User Access Control Policy in Internet of Things.

There are multiple types of services in the Internet of Things, and existing access control methods do not consider situations wherein the same types of services have multiple access options. In order to ensure the QoS quality of user access and realize the reasonable utilization of Internet of Things network resources, it is necessary to consider the characteristics of different services to design applicable access control strategies. In this paper, a preference-aware user access control strategy in slices is proposed, which can increase the number of users in the system while balancing slice resource utilization. First, we establish the user QoS model and slice QoS index range according to the delay, rate and reliability requirements, and we select users with multiple access options. Secondly, a user preference matrix is established according to the user QoS requirements and the slice QoS index range. Finally, a preference matrix of the slice is built according to the optimization objective, and access control decisions are made for users through the resource utilization state of the slice and the preference matrix. The verification results show that the proposed strategy not only balances slice resource utilization but also increases the number of users who can access the system.

Reference Intervals of Cytokeratin-19 Fragment (CYFRA 21-1) in Healthy Adults in China.

BACKGROUND: The reference intervals for serum cytokeratin-19 fragment (CYFRA 21-1) have not been established in Chinese population. This study aimed to measure serum CYFRA 21-1 levels in healthy Chinese subjects. METHODS: This cross-sectional, four-center study in two Chinese provinces enrolled participants (aged 18 - 85 years) with normal liver/kidney function and normal results for routine blood tests/urinalysis. Serum CYFRA 211 level was measured by ARCHITECT immunoassay (Abbott Diagnostics). RESULTS: The study included 3,366 participants. The median (interquartile range) value for serum CYFRA 21-1 level was 1.38 (1.00 - 1.89) ng/mL and tended to increase with age. The upper limit of the 97.5th percentile was 3.55 ng/mL and tended to increase with age. Serum CYFRA 21-1 median level varied between the four centers from 1.22 (0.89, 1.71) to 1.55 (1.12, 2.18) ng/mL, while the 97.5th percentile varied from 3.24 to 4.09 ng/mL. CYFRA 21-1 level correlated weakly with age and creatinine level. CONCLUSIONS: These new data can help to establish the 'normal range' of serum CYFRA 21-1 in people in China.

Magnetic apple pomace biochar: Simple preparation, characterization, and application for enriching Ag(I) in effluents.

In order to manage and utilize a large amount of wasted apple pomace, the magnetic biochar was prepared through pyrolysis of apple pomace at 600 °C in nitrogen environment, followed by immersion aging in Fe(II)/Fe(III) aqueous solution. The characterization of the resulting magnetic biochar, herein called the M600APB, showed that the saturation magnetization value and the Brunauer-Emmett-Teller (BET) specific surface area of M600APB were 9.52 emu/g and 102.18 m2/g, respectively. The batch adsorption showed that M600APB could preferentially enrich the low concentration of Ag(I) with the maximum adsorption capacity of 818.4 mg/g in an Ag(I)-Pb(II)-Cu(II)-Ni(II)-Zn(II) aqueous system at ambient temperature. The column adsorption experiments indicated that M600APB could effectively enrich and separate Ag(I) from the same aqueous mixture. The presumable mechanism of Ag(I) adsorption on M600APB involves intra-particle diffusion, coordination, ion exchange and reduction. This study provided an effective approach to both utilize wasted apple pomace and enrich the low concentration of Ag(I) in a sustainable way.