The Role of Polyamines in pH Regulation in the Extracellular Calcifying Medium of Scleractinian Coral Spats.

This study aims to elucidate a novel mechanism for elevating the pH within the calicoblastic extracellular calcifying medium (pH) of corals and demonstrate the potential contribution of calcifying organisms to CO sequestration. Departing from traditional models that attribute the increase in pH primarily to H expulsion via Ca-ATPase, we emphasize the significant role of polyamines. These ubiquitous biogenic amines conveyed by calicoblastic cells through polyamine transporters demonstrate a remarkable affinity for CO.

Quantum Chemical Analysis of Molecular and Fragment Ions Produced by Field Ionization of Methyl Stearate.

The formation of molecular and fragment ions observed in the field ionization mass spectrum of methyl stearate has been analyzed on the basis of quantum chemical calculations including time-dependent density functional theory (TDDFT) and natural bond orbital (NBO) analysis. The TDDFT calculations suggest that methyl stearate is ionized via two processes, namely a 7.43 eV excitation and a tunneling effect, while the high electric field of 10 V/m enables analyte molecules to ionize at an effective 6 eV lower than the 9.

Construction of a Mass Spectrum Library Containing Predicted Electron Ionization Mass Spectra Prepared Using a Machine Learning Model and the Development of an Efficient Search Method.

Electron ionization (EI) mass spectrum library searching is usually performed to identify a compound in gas chromatography/mass spectrometry. However, compounds whose EI mass spectra are registered in the library are still limited compared to the popular compound databases. This means that there are compounds that cannot be identified by conventional library searching but also may result in false positives.