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BaZrO 3 (BZO) nanorods are now incorporated into production IBAD-MOCVD coated conductors. Here we compare several examples of both BZO-free and BZO-containing coated conductors using critical current (I c ) characterizations at 4.2 K over their full angular range up to fields of 31 T. We find that BZO nanorods do not produce any c-axis distortion of the critical current density J c () curve at 4.2 K at any field, but also that pinning is nevertheless strongly enhanced compared to the non-BZO conductors. We also find that the tendency of the ab-plane J c () peak to become cusp-like is moderated by BZO and we define a new figure of merit that may be helpful for magnet design -the OADI (Off-Axis Double I c ), which clearly shows that BZO broadens the abplane peak and thus raises J c 5-30° away from the tape plane, where the most critical approach to I c occurs in many coil designs. We describe some experimental procedures that may make critical current I c tests of these very high current tapes more tractable at 4.2 K, where I c exceeds 1000 A even for 4 mm wide tape with only 1 m thickness of superconductor. A positive conclusion is that BZO is very beneficial for the J c characteristics at 4.2 K, just as it is at higher temperatures, where the correlated c-axis pinning effects of the nanorods are much more obvious.

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The critical current and structural properties of (Gd,Y)BaCuO tapes made by metal organic chemical vapor deposition (MOCVD) with Zr addition levels up to 30 at.% have been investigated. The reduction in critical current beyond the previously optimized Zr addition level of 7.5 at.% was found to be due to structural deterioration of the (Gd,Y)Ba 2 Cu 3 O x film. By a modified MOCVD process, enhanced critical current densities have been achieved with high levels of Zr addition, including 3.83 MA cm −2 in 15 at.% Zr-added 1.1 µm thick film at 77 K in zero magnetic field. Critical currents as high as 1072 A/12 mm have been reached in (Gd,Y)BaCuO tapes with 15 at.% Zr addition at 30 K in a field of 3 T applied perpendicular to the tape, corresponding to a pinning force value of 268 GN m −3 . The enhanced critical currents achievable with a high density of nanoscale defects by employing high levels of second-phase additions enable the performance targets needed for the use of HTS tapes in coil applications involving high magnetic fields at temperatures below 50 K to be met.

Small-molecule regulation is a powerful switching tool to manipulate cell signal transduction for a desired function; however, most available methods usually require genetic engineering to endow cells with responsiveness to user-defined small molecules. Herein, we demonstrate a nongenetic approach for small-molecule-controlled receptor activation and consequent cell behavior manipulation that is based on DNA-mediated chemically induced dimerization (D-CID). D-CID uses a programmable chemical-responsive DNA nanodevice to trigger DNA strand displacement and induce the activation of c-Met, a tyrosine kinase receptor cognate for hepatocyte growth factor, through dimerization. Through the use of various functional nucleic acids, including aptamers and DNAzymes, as recognition modules, the versatility of D-CID in inducing c-Met signaling upon addition of various small-molecular or ionic cues, including ATP, histidine, and Zn , is demonstrated. Moreover, owing its multi-input properties, D-CID can be used to manipulate the behaviors of multiple cell populations simultaneously in a selective and programmable fashion.

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With 298 heterogeneous soil samples from Yixing (Jiangsu Province), Zhongxiang and Honghu (Hubei Province), this study aimed to combine a successive projections algorithm (SPA) with a support vector machine regression (SVMR) model (SPA-SVMR model) to improve the estimation accuracy of soil organic carbon (SOC) contents using the laboratory-based visible and near-infrared (VIS/NIR, 350−2500 nm) spectroscopy of soils. The effects of eight spectra pre-processing methods, i.e., Log (1/R), Log (1/R) coupled with Savitzky-Golay (SG) smoothing (Log (1/R) + SG), first derivative with SG smoothing (FD), second derivative with SG smoothing (SD), SG, standard normal variate (SNV), mean center (MC) and multiplicative scatter correction (MSC), on SPA-based informative wavelength selection were explored. The SVMR model (i.e., SVMR without SPA) and SPA-PLSR model (i.e., SPA combined with partial least squares regression (PLSR)) were developed and compared with the SPA-SVMR model in order to evaluate the performance of SPA-SVMR. The results indicated that the variables selected by SPA and their distributions were strongly affected by different pre-processing methods, and SG was the optimal pre-processing method for SPA-SVMR model development; the SPA-SVMR model using SG pre-processing and 28 SPA-selected wavelengths obtained a better result (R 2 V = 0.73, RMSE V = 2.78 g·kg and RPD V = 1.63). Most of the spectral bands used by the SPA-SVMR model over the near-infrared region were important wavelengths for SOC content estimation. This study demonstrated that the combination of SPA and SVMR is feasible and reliable for estimating SOC content from the VIS/NIR spectra of soils in regions with multiple soil and land-use types.

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