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ABSTRACT The Indo‐Pacific lionfish,Pterois volitans,is an invasive species in the western Atlantic. Since its introduction to Florida in the early 1980s, populations have surged with lionfish now found from North Carolina to Venezuela. As their range expands, these generalist predators threaten native fauna, and while they are primarily a marine species, their tolerance for low salinity conditions may allow them to expand into sensitive estuarine habitats undetected. Traditional approaches for tracking invasive species such as direct observation or trapping are impractical over large spatial scales, making environmental DNA (eDNA) an attractive alternative. Molecular assays, such as those employing quantitative polymerase chain reaction (qPCR), amplify low copy number DNA fragments in environmental samples and are increasingly employed as a complement to traditional methods for the detection of invasive species. Currently, there is one published PCR assay for the detection of lionfish eDNA. However, the specificity of this assay is unverified, and the critical performance parameters limit of detection (LOD) and limit of quantification (LOQ) have not been established. Here we evaluate the efficacy of this assay and show that it is likely to result in false negatives in the western Atlantic. As an alternative, we developed a new TaqMan probe‐based qPCR assay that is species‐specific forP. volitansand highly sensitive with a LOD of 12 copies per reaction and a LOQ of 598 copies per reaction. While our assay does not amplify the closely relatedP. miles, which was also introduced in the western Atlantic, the low prevalence of this species in the invasive population means our assay is effective for most monitoring purposes. We conclude that our assay is a robust method for the detection of lionfish and can be employed in any habitat, offering new opportunities for controlling the spread of invasive lionfish. 

Abstract Integration of native bone into orthopedic devices is a key factor in long‐term implant success. The material‐tissue interface is generally accepted to consist of a hydroxyapatite layer so bioactive materials that can spontaneously generate this hydroxyapatite layer after implantation may improve patient outcomes. Per the ISO 22317:2014 standard, “Implants for surgery – In vitro evaluation for apatite‐forming ability of implant materials,” bioactivity performance statements can be assessed by soaking the material in simulated body fluid (SBF) and evaluating the surface for the formation of a hydroxyapatite layer; however, variations in test methods may alter hydroxyapatite formation and result in false‐positive assessments. The goal of this study was to identify the effect of SBF formulation on bioactivity assessment. Bioglass® (45S5 and S53P4) and non‐bioactive Ti‐6Al‐4V were exposed to SBF formulations varying in calcium ion and phosphate concentrations as well as supporting ion concentrations. Scanning electron microscopy and X‐ray powder diffraction evaluation of the resulting hydroxyapatite layers revealed that SBF enriched with double or quadruple the calcium and phosphate ion concentrations increased hydroxyapatite crystal size and quantity compared to the standard formulation and can induce hydroxyapatite crystallization on surfaces traditionally considered non‐bioactive. Altering concentrations of other ions, for example, bicarbonate, changed hydroxyapatite induction time, quantity, and morphology. For studies evaluating the apatite‐forming ability of a material to support bioactivity performance statements, test method parameters must be adequately described and controlled. It is unclear if apatite formation after exposure to any of the SBF formulations is representative of an in vivo biological response. The ISO 23317 standard test method should be further developed to provide additional guidance on apatite characterization and interpretation of the results. 

The mineral carbon sequestration capacity of basic oxygen furnace (BOF) slag offers great potential to absorb carbon dioxide (CO₂) from landfill emissions. The BOF slag is highly alkaline and rich in calcium (Ca) containing minerals that can react with the CO₂to form stable carbonates. This property of BOF slag makes it appealing for use in CO₂sequestration from landfill gas. In a previous study, CO₂and CH₄removal from the landfill gas was investigated by performing batch and column experiments with BOF slag under different moisture and synthetic landfill gas exposure conditions. The study showed two stage CO₂removal mechanism: (1) initial rapid CO₂removal, which was attributed to the carbonation of free lime (CaO) and portlandite [(Ca(OH)₂)], and (2) long-term relatively slower CO₂removal, which was attributed to be the gradual leaching of Ca²⁺from minerals (calcium-silicates) present in the BOF slag. Realising that the particle size could be an important factor affecting total CO₂sequestration capacity, this study investigates the effect of gradation on the CO₂sequestration capacity of the BOF slag under simulated landfill gas conditions. Batch and column experiments were performed with BOF slag using three gradations: (1) coarse (D₅₀ = 3.05 mm), (2) original (D₅₀ = 0.47 mm), and (3) fine (D₅₀ = 0.094 mm). The respective CO₂sequestration potentials attained were 255 mg g⁻¹, 155 mg g⁻¹, and 66 mg g⁻¹. The highest CO₂sequestration capacity of fine BOF slag was attributed to the availability of calcium containing minerals on the slag particle surface owing to the highest surface area and shortest leaching path for the Ca²⁺from the inner core of the slag particles.