Abstract:The phase transformation of iron minerals induced by aqueous Fe(II) (Fe(II) aq ) is a critical geochemical reaction which greatly affects the geochemical behavior of soil elements. How the geochemical behavior of rare earth elements (REEs) is affected by the Fe(II) aq -induced phase transformation of iron minerals, however, is still unknown. The present study investigated the adsorption and immobilization of REEs during the Fe(II) aq -induced phase transformation of ferrihydrite. The results show that the heavy REEs of Ho(III) were more efficiently adsorbed and stabilized compared with the light REEs of La(III) by ferrihydrite and its transformation products, which was due to the higher adsorptive affinity and smaller atomic radius of Ho(III). Both La(III) and Ho(III) inhibited the Fe atom exchange between Fe(II) aq and ferrihydrite, and sequentially, the Fe(II) aq -induced phase transformation rates of ferrihydrite, because of the competitive adsorption with Fe(II) aq on the surface of iron (hydr)oxides. Owing to the larger amounts of adsorbed and stabilized Ho(III), the inhibition of the Fe(II) aq -induced phase transformation of ferrihydrite affected by Ho(III) was higher than that by La(III). Our findings suggest an important role for the Fe(II) aq -induced phase transformation of iron (hydr)oxides in assessing the mobility and transfer behavior of REEs, as well as for their occurrence in earth surface environments.

Ferrihydrite (FHY), a widespread Fe­(III) (hydr)­oxide, is abundant in earth surface and critical in affecting the environmental behavior of soil elements, such as rare earth elements (henceforth referred to REEs). Under anoxic conditions, the coexisting Fe­(II) induces FHY conversion to the minerals with high crystallinity, such as lepidocrocite, goethite, or magnetite, where the phase transformation processes were affected by the coexisting ions. The interactions between REE ions (henceforth referred to Ln­(III)) and FHY in the transformation system, however, are still not well understood. We therefore investigated Fe­(II) aq -induced FHY transformation affected by four kinds of Ln­(III) (Ce3+, Nd3+, Tb3+, and Lu3+). The discernible inhibition was found among the different treatments with different Ln­(III), and both the FHY transformation and Fe atom exchange ratios decreased with coexistent Ln­(III) that have larger atomic number. In this study, the Fe atom exchange ratios with different coexistent Ln­(III) were linearly negatively depended on the molar enthalpy values of Ln­(III), which are explained by the molar enthalpy considered to be important in affecting the adsorption behaviors of Ln­(III). Furthermore, the adsorption behaviors can affect the incorporation efficiency of the Ln­(III), so as to affect the Fe atom exchange and FHY phase transformation. The Ln­(III) with larger atomic number can be stabilized more, which results from the effects of incompatible REEs in determining the efficiency of immobilizing Ln­(III) in the transformed iron (hydr)­oxides. Our research suggested the important role of FHY in the distribution of REEs and the key properties of REEs in affecting their different distribution characteristics in earth surface environments.

The rapid development of unmanned aerial vehicles (UAVs), miniature hyperspectral imagers, and relevant instruments has facilitated the transition of UAV-borne hyperspectral imaging systems from concept to reality. Given the merits and demerits of existing similar UAV hyperspectral systems, we presented a lightweight, integrated solution for hyperspectral imaging systems including a data acquisition and processing unit. A pushbroom hyperspectral imager was selected owing to its superior radiometric performance. The imager was combined with a stabilizing gimbal and global-positioning system combined with an inertial measurement unit (GPS/IMU) system to form the image acquisition system. The postprocessing software included the radiance transform, surface reflectance computation, geometric referencing, and mosaic functions. The geometric distortion of the image was further significantly decreased by a postgeometric referencing software unit; this used an improved method suitable for UAV pushbroom images and showed more robust performance when compared with current methods. Two typical experiments, one of which included the case in which the stabilizing gimbal failed to function, demonstrated the stable performance of the acquisition system and data processing system. The result shows that the relative georectification accuracy of images between the adjacent flight lines was on the order of 0.7–1.5 m and 2.7–13.1 m for cases with spatial resolutions of 5.5 cm and 32.4 cm, respectively.

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Introduction The efficacy and safety of ertugliflozin have not been well characterized in Asian populations with type 2 diabetes (T2D) and overweight or obesity as defined by the Chinese Diabetes Society [body mass index (BMI) ≥ 24 kg/m 2 ]. Methods These post hoc analyses of pooled data from two randomized, double-blind, 26-week studies assessed the efficacy and safety of ertugliflozin (5 mg or 15 mg) compared with placebo in participants from Asia with T2D and baseline BMI ≥ 24 kg/m 2 , with inadequate glycemic control on metformin. Longitudinal analyses were used to calculate least squares (LS) mean [95% confidence interval (CI)] change from baseline in glycemic indices and body weight. The proportions of participants achieving efficacy targets and experiencing adverse events (AEs) were assessed. Results The 445 participants had a mean age of 55.5 years, T2D duration 6.6 years, glycated hemoglobin (HbA1c) 8.1%, and BMI 27.6 kg/m 2 . At week 26, placebo-adjusted LS mean (95% CI) changes from baseline for ertugliflozin 5 mg and 15 mg, respectively, were − 0.78% (− 0.95% to − 0.61%) and − 0.80% (− 0.98% to − 0.63%) for HbA1c, and − 1.74 kg (− 2.29 kg to − 1.19 kg) and − 2.04 kg (− 2.60 kg to − 1.48 kg) for body weight. A greater proportion of participants receiving ertugliflozin 5 mg and 15 mg versus placebo, respectively, achieved HbA1c < 7.0% (42.1% and 46.3% vs. 13.9%), body weight reduction ≥ 5% (35.5% and 38.3% vs. 11.1%), and systolic blood pressure < 130 mmHg (42.4% and 34.5% vs. 21.7%). The proportion of participants with AEs was 52.6% (ertugliflozin 5 mg), 52.3% (ertugliflozin 15 mg), and 55.6% (placebo). Conclusions In participants from Asia with T2D inadequately controlled by metformin monotherapy, and BMI ≥24 kg/m 2 , ertugliflozin (5 mg or 15 mg) resulted in greater glycemic and body weight reductions compared with placebo and was generally well tolerated. Trial Registration Clinicaltrials.gov identifiers NCT02033889, NCT02630706. Supplementary Information The online version contains supplementary material available at 10.1007/s13300-022-01345-6.

In the original publication [...]