Impact of Inequivalent Wetting on the Face-Specific Dissolution Rates for Single Faceted-Crystals Predicted from Solid-State Binding Energies.

A methodology for the prediction of face-specific relative dissolution rates for single-faceted crystals accounting for inequivalent wetting by the solvent is presented. This method is an extended form of a recent binding energy model developed by the authors (Najib et al., Cryst. Growth & Des. 2021, 21(3), 1482-1495) for predicting the face-specific dissolution rates for single-faceted crystals from the solid-state intermolecular binding energies in a vacuum. The principal modification is that the equivalent wetting of the crystal surfaces is no longer assumed, since interactions between the crystal surfaces and the solution-state molecules are incorporated. These surface interactions have been investigated by using a grid-based systematic search method. The face-specific dissolution rates predicted by the extended binding energy model for ibuprofen in a 95% v/v ethanol-water solution and furosemide in an aqueous medium have been validated against the published experimental results and are in excellent agreement. This model is a step forward toward accurate predictions of the relative face-specific dissolution rates for a wide variety of faceted crystals in any dissolution medium.

Single-Molecule Magnetism in Three Dy2 Complexes from the Use of a Pentadentate Schiff Base Ligand and Different Benzoates.

Three dinuclear dysprosium(III) complexes, [Dy2 L2 (O2 CPh)2 ]⋅2 MeOH (1), [Dy2 L2 {(2-NO2 )O2 CPh}2 ] (2), and [Dy2 L2 {(2-OH)O2 CPh}2 ]⋅MeOH⋅MeCN (3) (H2 L=N1 ,N3 -bis(4-chlorosalicyladehyde)diethylenetriamine), have been synthesized and structurally characterized. Complexes 1-3 possess similar Ln2 cores and differ in substituents at the benzyl rings of benzoates. Direct current (dc) magnetic susceptibility studies in the 2-300 K range showed weak antiferromagnetic interactions between two dysprosium(III) ions in 1-3. The alternating current (ac) magnetic susceptibility measurements indicated that they all exhibited SMM behavior. The strategic attachment of the -NO2 group (in 2) and the -OH functionality (in 3) on the skeleton of the benzoic acid led to subtle variations of the bond lengths and bond angles in the coordination environments of the central dysprosium(III) ions, consequently resulting in the enhancement of the energy barriers for 2 and 3. Complete-active-space self-consistent field (CASSCF) calculations were employed to rationalize the experimental outcomes. Theoretical calculations confirm the existence of antiferromagnetic interactions in 1-3, and the calculated dc magnetic susceptibility data agree well with those obtained experimentally. The computational results reveal more axial g tensors, as well as higher first excited Kramers doublets in 2 and 3; thus resulting in higher energy barriers in compounds 2 and 3.

Validation of The Malay Version of Auditory Verbal Learning Test (MVAVLT) Among Schizophrenia Patients In Hospital Universiti Sains Malaysia (HUSM), Malaysia

Objective: Many studies have emphasized the significance of verbal memory for the functional outcome in schizophrenia. A preserved capability to encode and recall verbal information is essential for the long-term efficacy of psychoeducational programs and other psychological intervention to ensure the successful transfer of newly acquired skills or knowledge into everyday life. Aims of this study aimed to validate the MVALT among schizophrenia patients in HUSM. Methods: The subjects were 15 schizophrenia patients conveniently selected from the patients that attended follow up at the psychiatry clinic in HUSM or inpatients who have been admitted during the study period and 15 healthy control subjects as a comparison. Reliability and validity of the MVAVLT were analyzed. Results: The validation study showed that the Malay version Auditory Verbal Learning Test (MVAVLT) had a good validity (factor analysis 0.66 to 0.98) and test-retest reliability (pearson correlation ranged from 0.24 to 0.84) and has been shown to be sensitive in discriminating between normal and schizophrenia patients. In line with the previous research, the schizophrenia patients performed significantly worse than healthy control in all indexes measured in MVAVLT. Conclusion: The screening of deficits in verbal learning and memory among the schizophrenia patients is important, for early detection and treatment since it can be helpful for clinicians and psychologists in their counseling sessions. Subsequently, it helps patients to reduce such cognitive difficulties and their impact by using specific rehabilitation with the usage of newer antipsychotic agents.