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Abstract Congenital heart diseases have rarely been described in rabbits. The purpose of the present case report is to describe the clinical, radiographic, echocardiographic, and pathological features of a partial atrioventricular septal defect in a pet rabbit. A 3-month-old, 380-g male vaccinated pet rabbit was presented for decreased activity, increased respiratory rate and effort, anorexia, and decreased fecal output of 2 days duration. Total body radiographic images revealed severe cardiomegaly associated with enlarged caudal pulmonary vessels and increased interstitial to alveolar lung pattern. Echocardiographic imaging showed evidence of distended heart chambers, abnormal flow through the atria, and mitral valve regurgitation. The rabbit was treated with furosemide and an angiotensin-converting enzyme inhibitor but rapidly deteriorated and died. Necropsy confirmed the dilation of both ventricles and the presence of a partial atrioventricular septal defect associated with an ostium primum atrial septal defect just over the tricuspid valve and the mitral valve. [ABSTRACT FROM AUTHOR]

The lithospheric structure of ancient cratons provides important constraints on models relating to tectonic evolution and mantle dynamics. Here we present the 3D lithospheric structure of the North China Craton (NCC) from a joint inversion of gravity, geoid and topography data. The NCC records a prolonged history of Archean and Paleoproterozoic accretion of crustal blocks through subduction and collision building the cratonic architecture, which was subsequently differentially destroyed during Mesozoic through extensive magmatism. The thermal structure obtained in our study is considered to define the lithosphere-asthenosphere boundary (LAB) of the NCC, and reflects the density variations within the mantle lithosphere. Employing the Moho depths from deep seismic sounding profiles for the inversion, and based on repeated computations using different parameters, we estimate the Moho depth, LAB depth and average crustal density of the craton. The Moho depth varies from 28 to 50 km and the LAB depth varies from 105 to 205 km. The LAB and Moho show concordant thinning from West to East of the NCC. The average crustal density is 2870 kg m − 3 in the western part of the NCC, higher than that in the eastern part (2750 kg m − 3 ). The results of joint inversion in our study yielded LAB depth and lithospheric thinning features similar to those estimated from thermal and seismic studies, although our results show different depth and variations in the thickness. The lithosphere gently thins from 145 to 105 km in the eastern NCC, where as the thinning is much less pronounced in the western NCC with average depth of about 175 km. The joint inversion results in this study provide another perspective on the lithospheric structure from the density properties and corresponding geophysical responses in an ancient craton. [ABSTRACT FROM AUTHOR]

• CO 2 fluxes were measured using a variety of feedstocks that are applicable to enhanced weathering including kimberlite, brucite, forsterite, serpentinite, and wollastonite. • Mineralogical composition and reactivity had the greatest impact on CO 2 drawdown. • Negative fluxes of -2940 g CO 2 /m2/yr were achieved using highly reactive brucite. • CO 2 removal rates of -870 g CO 2 /m2/yr (1.5% offset in mines emissions) were achieved for mine residues when labile Mg is present. • Mine waste management practices that enhance exposure will lead to greater CO 2 removal. Enhanced rock weathering (ERW) sequesters CO 2 via solubility and mineral trapping and can be implemented by the mining industry to reduce their net greenhouse gas emissions. Kimberlite residues from Venetia Diamond Mine in South Africa, as well as powdered forsterite, serpentinite, wollastonite skarn, and 10 wt.% brucite mixed with quartz sand, were tested as potential feedstocks for ERW. A CO 2 flux system directly measured CO 2 removal rates and sensors tracked laboratory conditions and pore water saturation during a series of 2-week experiments. With respect to kimberlites, unweathered residues achieved the greatest drawdown rate of -870 g CO 2 /m2/yr at 48% saturation. In contrast, fine and coarse residues previously exposed to mine process water achieved fluxes of -150 and -160 g CO 2 /m2/yr at 60% saturation. Brucite reached -2940 g CO 2 /m2/yr at 14% saturation compared to forsterite, serpentinite, and wollastonite that achieved fluxes of -500, -260, and -190 g CO 2 /m2/yr, respectively, at higher saturations of 53–60%. Mineralogical composition had the greatest effect on CO 2 fluxes, followed by water content which drives carbonation reactions and affects permeability. Solid inorganic carbon increased in the brucite, wollastonite, and unweathered kimberlite, indicating that CO 2 was stored via mineral trapping as opposed to solubility trapping in the other experiments. Increasing the exposure of unweathered residues, expanding dispersal area, and optimizing water saturation would lead to greater CO 2 removal at mine sites. [ABSTRACT FROM AUTHOR]