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  1. Singer, B. ; Jiang, G. (Ed.)
    The Qaidam Basin marks a crucial boundary between the Westerlies and the Asian summer monsoons. Previous studies in the Qaidam Basin have advanced our knowledge of the paleoclimate over glacial to interglacial cycles. However, our understanding of the paleoclimatic sensitivity of the Qaidam Basin to the relative strength of these two climatic driving forces remains limited due to the lack of regional paleoclimatic reconstructions. The Qaidam Basin is proposed as a regional and global eolian dust source during the glacial periods, during which a cold, dry climate is associated with the equatorward shift of the jet stream. On the contrary, paleoshoreline records suggest that a highstand lake stage prevailed in late Marine Isotope Stage 3 (MIS 3) and lasted until 15 ka. To address this conundrum, we have applied an integrated approach to reconstructing the regional paleoclimatic history by combining compound-specific isotope analysis, lake temperature reconstruction, and numerical modeling. Our results show varying paleoclimate associated with the dynamic climate boundary since 45 ka: (1) a wet climate during late MIS 3, when the Asian summer monsoons are strengthened under high summer insolation and penetrate further into Central Asia; (2) a general cold, dry but wetter than at present climate in the Last Glacial Maximum (LGM), when the Asian summer monsoons retreat and the Westerlies become dominant; and (3) three short periods of extreme aridity corresponding to the Younger Dryas and Heinrich 2 and 4 events, when the normal moisture transport via the Westerlies and Asian summer monsoons is interrupted. The numerical modeling supports an increase in the effective precipitation during the LGM due to reduced evaporation under low summer insolation. These results suggest that the Westerlies and Asian summer monsoons alternately controlled the climate in the Qaidam Basin in response to precessional forcing during the late Pleistocene. 
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  2. Polymorphic gates are reconfigurable devices that deliver multiple functionalities at different temperature, supply voltage or external inputs. Capable of working in different modes, polymorphic gate is a promising candidate for embedding secret information such as fingerprints. In this paper, we report five polymorphic gates whose functionality varies in response to specific control input and propose a circuit fingerprinting scheme based on these gates. The scheme selectively replaces standard logic cells by polymorphic gates whose functionality differs with the standard cells only on Satisfiability Don’t Care conditions. Additional dummy fingerprint bits are also introduced to enhance the fingerprint’s robustness against attacks such as fingerprint removal and modification. Experimental results on ISCAS and MCNC benchmark circuits demonstrate that our scheme introduces low overhead. More specifically, the average overhead in area, speed and power are 4.04%, 6.97% and 4.15% respectively when we embed 64-bit fingerprint that consists of 32 real fingerprint bits and 32 dummy bits. This is only half of the overhead of the other known approach when they create 32-bit fingerprints. 
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  3. Abstract

    For brain computer interfaces (BCI), the immune response to implanted electrodes is a major biological cause of device failure. Bioactive coatings such as neural adhesion molecule L1 have been shown to improve the biocompatibility, but are difficult to handle or produce in batches. Here, a synthetic zwitterionic polymer coating, poly(sulfobetaine methacrylate) (PSBMA) is developed for neural implants with the goal of reducing the inflammatory host response. In tests in vitro, the zwitterionic coating inhibits protein adsorption and the attachment of fibroblasts and microglia, and remains stable for at least 4 weeks. In vivo two‐photon microscopy on CX3CR1‐GFP mice shows that the zwitterionic coating significantly suppresses the microglial encapsulation of neural microelectrodes over a 6 h observation period. Furthermore, the lower microglial encapsulation on zwitterionic polymer‐coated microelectrodes is revealed to originate from a reduction in the size but not the number of microglial end feet. This work provides a facile method for coating neural implants with zwitterionic polymers and illustrates the initial interaction between microglia and coated surface at high temporal and spatial resolution.

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  4. Abstract Aims

    To determine whether HbA1cmismatches (HbA1clevels that are higher or lower than expected for the average glucose levels in different individuals) could lead to errors if diagnostic classification is based only on HbA1clevels.


    In a cross‐sectional study, 3106 participants without known diabetes underwent a 75‐g oral glucose tolerance test (fasting glucose and 2‐h glucose) and a 50‐g glucose challenge test (1‐h glucose) on separate days. They were classified by oral glucose tolerance test results as having: normal glucose metabolism; prediabetes; or diabetes. Predicted HbA1cwas determined from the linear regression modelling the relationship between observed HbA1cand average glucose (mean of fasting glucose and 2‐h glucose from the oral glucose tolerance test, and 1‐h glucose from the glucose challenge test) within oral glucose tolerance test groups. The haemoglobin glycation index was calculated as [observed – predicted HbA1c], and divided into low, intermediate and high haemoglobin glycation index mismatch tertiles.


    Those participants with higher mismatches were more likely to be black, to be men, to be older, and to have higherBMI(allP<0.001). Using oral glucose tolerance test criteria, the distribution of normal glucose metabolism, prediabetes and diabetes was similar across mismatch tertiles; however, using HbA1ccriteria, the participants with low mismatches were classified as 97% normal glucose metabolism, 3% prediabetes and 0% diabetes, i.e. mostly normal, while those with high mismatches were classified as 13% normal glucose metabolism, 77% prediabetes and 10% diabetes, i.e. mostly abnormal (P<0.001).


    Measuring only HbA1ccould lead to under‐diagnosis in people with low mismatches and over‐diagnosis in those with high mismatches. Additional oral glucose tolerance tests and/or fasting glucose testing to complement HbA1cin diagnostic classification should be performed in most individuals.

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