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At least 1,513 records · Page 84

Graph-based featurization methods for classifying small molecule compounds

For over a decade, drug-induced liver injury (DILI) has posed significant drawbacks in the synthesis and development of drugs and remains a consequential concern. With finite success within the existing preclinical models, DILI is one of the main causes of drug withdrawal or termination from the market. Particularly, this withdrawal occurs during the late stages of drug development (Kullak-Ublick, 2017). Since DILI is difficult to diagnose and treat, it has become an obstacle in the drug production market that in turn affects clinicians, pharmaceutical companies, and consumers. We propose a method for learning features of DILI-positive drugs based on the graphical relationships and patterns they possess within a network of biological databases. We also train various statistical and machine learning models on these learned features in order to classify the drugs as DILI-positive or negative. Our methods include Random Forest, Neural networks, and logistic regression classification. We utilize labeled DILI-positive and DILI-negative datasets, which were developed by the FDA and the National center for toxicological research, as well as additional literature datasets (Thakkar, 2020) in order to validate our results and assess our featurization and model accuracy.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

TRACER-MAP_2022_volatile_organic_compounds_PTRMS

VOCs collected by quadrupole proton transfer reaction mass spectrometry for July-August 2022. A description of this instrument is included in the related publication. The location of the measurement is indicated by latitude and longitude coordinates; TRACER-MAP included time at the AMF site in La Porte and additional sites around Houston. Data below the minimum detection limit are not included here.

54 ENVIRONMENTAL SCIENCES↗

Probing U 5f Covalency in Uranium Compounds through Oxidant 2p Bonding

Oxidant K (1s) X-ray Emission Spectroscopy (XES) was used to investigate covalency in the Oxidant 2p – Uranium 5f bonds of Uranium Dioxide (UO 2 ) and Uranium Tetrafluoride (UF 4 ). It will be shown that the width of the 2p Occupied Density of States (ODOS), determined from the XES measurements, correlates with the increased 5f covalency of UO 2 and the increased ionicity of UF 4 . Analysis of the XES results includes comparison to spectral simulations, cluster calculations and peak fitting, demonstrating the potential of the oxidant XES measurements as a probe of 5f covalency.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗

Oval-cycloidal Magnetic Structure with Phase-shift in the Non-centrosymmetric Tetragonal Compound CePdSi 3

CePdSi 3 with H // [100] exhibits multiple metamagnetic transitions. Since there is no frustration in this system, it is suggested that the origin of the multiple metamagnetic transitions is the influence of the antisymmetric spin–orbit interaction. To clarify the magnetic structure under the influence of the antisymmetric spin–orbit interaction, neutron diffraction experiments have been performed using single crystal samples of CePdSi3. There are observed magnetic reflections with incommensurate magnetic propagation vector q=(0.315,0,0) in the phase I. In addition, additional magnetic reflections were also observed in the phase III. The magnetic structure was found to be an oval-cycloidal structure at the phase III in CePdSi 3 , and we discuss the origin of the unusual magnetic structure.

36 MATERIALS SCIENCE↗

Flexible honeycomb structure can bend to fit compound curves

For flexibility in forming a curved surface, a honeycomb configuration using multiple pleats has proved superior to the usual core structures. The partial pleats formed in individual cell walls permit movements to and from the central axis without tearing.

Carmody, R. J.↗

Didymium compound improves nickel-cadmium cell

Nickel electrodes impregnated with an additive solution of didymium hydrate and nitric acid mixed with nickel nitrate increases ampere-hour capacity of cells and does not affect the voltage characteristics.

Source record↗

Xenon forms stable compound with fluorine

Experiments show that xenon and fluorine combine readily at 400 deg C to form xenon tetrafluoride, which is colorless, crystalline, chemically stable and solid at room temperature. This process can be used for the separation of xenon from mixtures with other noble gases.

Claassen, H. H.↗