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Abstract Objective Idiopathic infantile hypercalcemia (IIH) is a rare disorder of PTH-independent hypercalcemia. CYP24A1 and SLC34A1 gene mutations cause two forms of hereditary IIH. In this study, the clinical manifestations and molecular aspects of six new Chinese patients were investigated. Methods The clinical manifestations and laboratory study of six patients with idiopathic infantile hypercalcemia were analyzed retrospectively. Results Five of the patients were diagnosed with hypercalcemia, hypercalciuria, and bilateral medullary nephrocalcinosis. Their clinical symptoms and biochemical abnormalities improved after treatment. One patient presented at age 11 years old with arterial hypertension, hypercalciuria and nephrocalcinosis, but normal serum calcium. Gene analysis showed that two patients had compound heterozygous mutations of CYP24A1, one patient had a monoallelic CYP24A1 variant, and three patients had a monoallelic SLC34A1 variant. Four novel CYP24A1 variants (c.116G > C, c.287T > A, c.476G > A and c.1349T > C) and three novel SLC34A1 variants (c.1322 A > G, c.1697_1698insT and c.1726T > C) were found in these patients. Conclusions A monoallelic variant of CYP24A1 or SLC34A1 gene contributes to symptomatic hypercalcemia, hypercalciuria and nephrocalcinosis. Manifestations of IIH vary with onset age. Hypercalcemia may not necessarily present after infancy and IIH should be considered in patients with nephrolithiasis either in older children or adults.

Key improvements are needed for implementation of the Endangered Species Act

Currently 1677 species are listed under the U.S. Endangered Species Act (ESA), yet only a small percentage have been delisted due to recovery. In the fall of 2021, the U.S. Fish and Wildlife Service proposed delisting 23 species due to extinction. Tracking changes in species 'recovery status over time is critical to understanding species' statuses, informing adaptive management strategies, and assessing the performance of the ESA to prevent further species loss. In this paper, we describe four key obstacles in tracking species recovery status under the ESA. First, ESA 5‐year reviews lack a standardized format and clear documentation. Second, despite having been listed for decades, many species still suffer major data gaps in their biology and threats, rendering it difficult if not impossible to track progress towards recovery. Third, many species have continued declining after listing, yet given the above (1 & 2), understanding potential causes (proximate and/or ultimate) can be difficult. Fourth, many species currently have no path to clear recovery, which represents a potential failing of the process. We conclude with a discussion of potential policy responses that could be addressed to enhance the efficacy of the ESA. [ABSTRACT FROM AUTHOR]

The Endangered Species Act (ESA) provides legal protection to imperiled populations and their associated habitats. As a part of this process, listed species must undergo a general status review (also called 5‐Year Review) to assess the progress toward recovery every 5 years. However, almost all 5‐year reviews result in a status of "no change," prompting scientists to question if the review process is robust enough to detect changes in recovery. The U.S. Fish and Wildlife Service (USFWS) was therefore interested in developing a standardized metric for monitoring more nuanced recovery progress as part of the status review. In collaboration with the USFWS, over 75 biologists from five different organizations developed and tested a set of novel metrics to summarize recovery progress of listed species by considering current and future conditions, threats, and conservation measures. We found that, although the majority of species had reviews with a recommendation of no change, scorers were able to use the metrics to interpret more nuanced changes in the 3Rs (resiliency, redundancy, and representation), threats, and conservation measures than in the status review. Our results suggest that these metrics could illuminate more nuanced areas of recovery and decline in species' conditions, but consistency among scorers and status reports should be a focus of future development. Our approach offers a rigorous set of metrics to systematically track the recovery progress of all ESA species. [ABSTRACT FROM AUTHOR]

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The iron ore sintering process is the main source of NOx emissions and accounts for about 48% of the total NOx emissions in the iron and steel industry. The generated NOx is mainly from fuel consumption, and it usually exists in the form of quasi-particle in iron ore sintering bed. Therefore, it is important to deeply understand the combustion characteristics and NOx formation mechanism of quasi-particles in iron ore sintering process. Based on this, the effects of coke breeze particle size, presence of an adhering layer of quasi-particles, adhering ratio of quasi-particle, and coke breeze content on the mass conversion rate of different types of quasiparticles and conversion rate of fuel-N to NOx were investigated in a vertical quartz tube reactor in detail. The results show that the mass conversion rate decreases with increasing coke breeze particle size for S'- and S-type quasi-particles; the conversion rate of fuel-N to NOx decreases with increasing coke breeze particle size for S'-type quasi-particle and exhibits the opposite trend for S-type quasi-particle, which is because of the presence of an adhering layer consisting of fine iron ore and limestone. Considering the combustion characteristics of S-and S'-type quasi-particles, the presence of an adhering layer of quasi-particles favors the increase of mass conversion rate and conversion rate of fuel-N to NOx. The mass conversion rate and conversion rate of fuel-N to NOx both decrease with increasing adhering ratio for C-type quasi-particles whose adhering layer consists of fine limestone and coke breeze. For P-type quasi-particles comprising coke breeze, fine limestone, and fine iron ore, the mass conversion rate decreases with increasing coke breeze content. The conversion rate of fuel-N to NOx is not linear and reaches the lowest value when coke breeze content is 50%.

Pr0.5Sr0.5Cr0.1Fe0.9−xNixO3−δ (PSCFNx, x = 0.1, 0.2) catalysts are prepared and utilized as electrodes in symmetric solid oxide fuel cells (SOFCs) for the hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR). Although the PSCFNx cathode retains its perovskite phase during operation in SOFCs, the anode is totally decomposed and decorated with an exsolved metallic Ni–Fe alloy (denoted as re-PSCFNx) in a reducing atmosphere. Electrochemical impedance spectroscopy (EIS) combined with distribution of relaxation times (DRT) analysis reveals that the rate-limiting step for the HOR at the anode is the hydrogen adsorption–dissociation process, while the charge transfer process is found to dominate the ORR at the cathode. As the doping of Ni is increased, the cathode polarization resistance for the ORR decreases from 0.19 Ω cm2 for PSCFN0.1 to 0.09 Ω cm2 for PSCFN0.2 at 800 °C in air. A similar trend is observed for the anode polarization resistance for the HOR, which exhibits a reduction from 2.46 Ω cm2 of re-PSCFN0.1 to 1.28 Ω cm2 of re-PSCFN0.2 at 800 °C in H2. When fueled with hydrogen, a single cell based on the PSCFN0.2/La0.8Sr0.2Ga0.8Mg0.2O3−δ (LSGM)(240 μm)/re-PSCFN0.2 configuration delivers a maximum power density of 623 mW cm−2 and slight performance degradation when operated for 220 h at 800 °C. Ni doping results in the charge redistribution of B-site ions. Increasing the doping level of Ni results in additional electron transfer channels and oxygen vacancies that adsorb more oxygen species, which facilitates the ORR performance. Furthermore, an increase in the number of Ni–Fe nanoparticles and creation of abundant interfaces in the anode promote the HOR. This work suggests that PSCFN0.2 has the potential to be an excellent electrode material for a symmetric SOFC. [ABSTRACT FROM AUTHOR]