Comprehensive bioinformatics study reveals targets and molecular mechanism of hesperetin in overcoming breast cancer chemoresistance

Molecular Diversity - The effectiveness of chemotherapy in breast cancer treatment can be increased using a combinatorial agent. Hesperetin has been reported to increase the sensitivity of...     

NMR Crystallography Enhanced by Quantum Chemical Calculations and Liquid State NMR Spectroscopy for the Investigation of Se-NHC Adducts**

N-heterocyclic carbene ligands (NHC) are widely utilized in catalysis and material science. They are characterized by their steric and electronic properties. Steric properties are usually quantified on the basis of their static structure, which can be determined by X-ray diffraction. The electronic properties are estimated in the liquid state; for example, via the ⁷⁷Se liquid state NMR of Se-NHC adducts. We demonstrate that ⁷⁷Se NMR crystallography can contribute to the characterization of the structural and electronic properties of NHC in solid and liquid states. Selected Se-NHC adducts are investigated via ⁷⁷Se solid state NMR and X-ray crystallography, supported by quantum chemical calculations. This investigation reveals a correlation between the molecular structure of adducts and NMR parameters, including not only isotropic chemical shifts but also the other chemical shift tensor components. Afterwards, the liquid state ⁷⁷Se NMR data is presented and interpreted in terms of the quantum chemistry modelling. The discrepancy between the structural and electronic properties, and in particular the π-accepting abilities of adducts in the solid and liquid states is discussed. Finally, the ¹³C isotropic chemical shift from the liquid state NMR and the ¹³C tensor components are also discussed, and compared with their ⁷⁷Se counterparts. ⁷⁷Se NMR crystallography can deliver valuable information about NHC ligands, and together with liquid state ⁷⁷Se NMR can provide an in-depth outlook on the properties of NHC ligands.     

Two Tilts of Higher Spherical Algebras

We introduce and study two exotic families of finite-dimensional algebras over an algebraically closed field. We prove that every such an algebra is derived equivalent to a higher spherical algebra studied by Erdmann and Skowroński (Arch. Math. 114, 25–39, 2020), and hence that it is a tame symmetric periodic algebra of period 4. This together with the results of Erdmann and Skowroński (Algebr. Represent. Theor. 22, 387–406, 2019; Arch. Math. 114, 25–39, 2020) shows that every trivial extension algebra of a tubular algebra of type (2,2,2,2) admits a family of periodic symmetric higher deformations which are tame of non-polynomial growth and have the same Gabriel quiver, answering the question recently raised by Skowroński.

     

New Mesoporous Aluminosilicates Used for Solid-phase Extraction of Hydrocarbons and Fragrance Compounds

The extraction efficiency of three newly synthesized mesoporous aluminosilicate materials with different Si/Al ratios was evaluated. The surface morphology and pore sizes of new mesoporous materials were determined, and the adsorption properties were examined. Scanning electron microscopy–energy dispersive spectroscopy was used to characterize the Al content in the material. The Brunauer, Emmett, Teller Isotherm method was used for determining the surface area and the pore size of synthesized materials. The adsorption properties of examined materials were evaluated by solid-phase extraction in classical form and using microsolid-phase extraction. In addition, the use of the examined aluminosilicates was investigated as sorbents for hydrocarbons and fragrance compounds.     

Allocation of School Bus Contracts By Integer Programming

When public transport is put out to tender, the task of allocating contracts to operators can be far from trivial. In addition to vehicle constraints, there can be group bids wherein a discount is offered for certain contracts in combination. An efficient integer programming formulation is presented which is then used to solve a large-scale real-life example.     

EMPIRICAL EVALUATION OF EXPECTED RETURNS FROM RESEARCH ON STOCK STRUCTURE FOR DETERMINATION OF TOTAL ALLOWABLE CATCH

An approach to incorporating new information using Bayes' theorem is applied to obtain estimates of expected returns from research on stock structure for determination of total allowable catch (TAC). Expected returns are measured relative to quantitative performance criteria that are inferred from fishery management objectives. Principles of the approach are outlined and a detailed case study of Tasmanian orange roughy is reported.