Grassmann Extrapolation for Accelerating Geometry Optimization.

This study extends the Grassmann extrapolation (G-Ext) method, which was introduced for Born-Oppenheimer molecular dynamics, to the context of geometry optimization. Using density matrices from previous optimization steps, the G-Ext approach applies a nonlinear, structure-preserving mapping onto the Grassmann manifold to provide an initial guess which accelerates the convergence of the self-consistent field (SCF) procedure. Using the optimal parameters identified by employing various descriptors and computational strategies across a diverse set of molecules, G-Ext shows excellent performance improvements, particularly with large molecular systems.

Importance of Polarizable Embedding for Computing Optical Rotation: The Case of Camphor in Ethanol.

Solvation effects on optical rotation are notoriously challenging to model for computational chemistry, as the specific rotatory power of a molecule can vary wildly going from apolar to polar or even protic solvents. To address such a problem, we present a polarizable embedding implementation of an electric and magnetic response property based on density functional theory and the AMOEBA polarizable force field, and apply such an implementation to the study of the optical rotation of camphor in ethanol. By comparing a continuum model, and electrostatic and polarizable embedding QM/MM models, we observe that accounting for the environment's polarization gives rise to not only a different quantitative prediction, in very good agreement with experiments for the QM/AMOEBA model, but also to a very different qualitative picture, with the values of the optical rotation computed along a classical molecular dynamics trajectory with electrostatic embedding being statistically uncorrelated to the ones obtained with the polarizable description.

The OpenMMPol library for polarizable QM/MM calculations of properties and dynamics.

We present a new library designed to provide a simple and straightforward way to implement QM/AMOEBA (Atomic Multipole Optimized Energetics for Biomolecular Applications) and other polarizable QM/MM (Molecular Mechanics) methods based on induced point dipoles. The library, herein referred to as OpenMMPol, is free and open-sourced and is engineered to address the increasing demand for accurate and efficient QM/MM simulations. OpenMMPol is specifically designed to allow polarizable QM/MM calculations of ground state energies and gradients and excitation properties.

Tissue Sealant Impact on Skull Base Reconstruction Outcomes: A Systematic Review and Meta-Analysis.

Objective: Despite significant advances in understanding of skull base reconstruction principles, the role of tissue sealants in modifying postoperative cerebrospinal fluid (CSF) leak outcomes remains controversial. We evaluate postoperative CSF leak incidence associated with tissue sealant use in skull base defect repair during endoscopic skull base surgery (ESBS).

Data Sources: Web of Science, PubMed/MEDLINE, Scopus, and Cochrane Library.

The impact of facility type and volume on treatment and overall survival in craniopharyngioma.

Background: Craniopharyngiomas are uncommon benign sellar and parasellar tumors with high overall survival (OS) and recurrence rates. Treatment is often surgical but may include adjuvant therapies. The impact of adjuvant therapy and surgical approach have been evaluated, however, facility volume and type have not.