Box-and-whisker plots or simply boxplots are powerful graphical representations that give an overview of a data set. In this work five different examples illustrate the applications of boxplots in food chemistry. The examples involve relative sweetness of sugars and sugar alcohols with respect to sucrose, the potassium content of fruits and vegetables, amino acid content of egg white and yolk, chemical composition of freshwater and saltwater fish, and change in fatty acid composition of soybean oil through traditional cultivation or genetic engineering techniques. Readers are guided to identify through boxplots key features present in some foods associated with inorganic elements and molecules. It is certainly an interdisciplinary way of studying concepts of statistics, nutrition, and chemistry.

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Artemisinin and some derivatives with activity against D-6 strains of Plasmodium falciparum were studied. Molecular electrostatic potential (MEP) maps were used in an attempt to identify key features of the compounds that are necessary for their activities, and then use those to propose new artemisinin derivatives. The partial least squares (PLS) method was then used to generate a predictive model. The PLS model with three latent variables explaining 88.9% of total variance, with Q((2)) = 0.839 and R(2) = 0.935, was obtained for 15/6 compounds in the training/external validation set. For construction of the model, the most important descriptors were the highest occupied molecular orbital (HOMO) energy, atomic charges on the atoms O1 (Q(1)) and C3 (Q(3)), molecular volume (VOL), and hydrophilic index (HYF). From a set of 20 proposed artemisinin derivatives, one new compound (39) with higher antimalarial activity than the molecules initially studied was predicted. Synthesis of these new derivatives may follow the results of the MEP maps studied and the PLS modeling.

Artemisinin and 18 derivatives with antimalarial activity against W-2 strains of Plasmodium falciparum were studied through quantum chemistry and multivariate analysis. The geometry optimization of the structures was realized with the Hartree-Fock (HF) theory and 3-21G basis set. Maps of molecular electrostatic potential (MEP) and molecular docking were used to investigate the interaction between the ligands and the receptor (heme). Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were employed to select the most important descriptors related to activity. A predictive model was generated by the Partial Least Square (PLS) method through 15 molecules and 4 used as an external validation set, which were selected in the training set, the validation parameters of which are Q2 = 0.85 and R2 = 0.86. The model included as molecular parameters, the radial distribution function, RDF060e, the hydration energy, HE, and the distance between the O1 atom from the ligand and the iron atom from heme, d(Fe-O1). Thus, the synthesis of new derivatives may follow the results of the MEP maps and the PLS analysis

In a previous article, we used Hartree-Fock (HF) theory to study the piezoelectricity in BaTiO₃. In this paper, we applied the Douglas-Kroll-Hess second order scalar relativistic method to investigate the possible piezoelectric properties in the perovskite YFeO₃ structure, which has not yet been studied experimentally. The 30s20p13d and 31s21p17d Gaussian basis sets for the Fe (⁵D) and Y (²D) atoms, respectively, were built with the Generator Coordinate HF method. After contraction to [13s7p5d] and [13s8p7d], in combination with the 20s14p/6s4p basis set for the O (³P) atom from literature, they had their quality evaluated using calculations of the total and the orbital energies for the ²FeO⁺¹ and ¹YO⁺¹ fragments. The dipole moment, the total energy, and the total atomic charges in YFeO₃ in C(s) space group were calculated. The results and the analysis lead us to believe that the perovskite YFeO₃ does not present piezoelectric properties.