Pioneer Jupiter orbiter probe mission 1980, probe description

The adaptation of the Saturn-Uranus Atmospheric Entry Probe (SUAEP) to a Jupiter entry probe is summarized. This report is extracted from a comprehensive study of Jovian missions, atmospheric model definitions and probe subsystem alternatives

The effect of ionization on the infrared absorption spectra of PAHs: A preliminary report

The emission lines observed in many interstellar IR sources at 3.28, 6.2, 7.7, 8.7, and 11.3 microns are theorized to originate from polycyclic aromatic hydrocarbons (PAHs). These assignments are based on analyses of lab IR spectra of neutral PAHs. However, it is likely that in the interstellar medium that PAHs are ionized, i.e., are positively charged. Besides, as pointed out by Allamandola et al., although the IR emission band spectrum resembles what one might expect from a mixture of PAHs, it does not match in details such as frequency, band profile, or relative intensities predicted from the absorption spectra of any known PAH molecule. One source of more information to test the PAH theory is ab initio molecular orbital theory. It can be used to compute, from first principles, the geometries, vibrational frequencies, and vibrational intensities for model PAH compounds which are difficult to study in the lab. The Gaussian 86 computer program was used to determine the effect of ionization on the infrared absorption spectra of several small PAHs: naphthalene and anthracene. A preliminary report is presented of the results of these calculations

Structural Determinants for Reversible β-lactamase Inhibition

Antibiotic resistance is one the largest health concerns of the modern era, threatening decades of progress in antibacterial research and development. β-lactams, the first line of defense against most Gram positive and negative pathogens, are increasingly ineffective in clinical settings, driven in large part by the proliferation of β-lactamases, enzymes which degrade β-lactams. While these proteins have evolved over millions of years with hundreds of known variants, clinical selection has led to the proliferation of extended spectrum β-lactamases and carbapenems like CTX-M and KPC-2, respectively. Previous generation β-lactamase inhibitors such as clavulanic acid and sulbactam are ineffective against these enzymes, creating a pressing need for new inhibitor development.While the recent discovery and approval of covalent avibactam and vaborbactam have shown great promise in bridging this gap, further clinical selection will likely drive new enzymes and mutations resistant to these agents, such as the spread of metallo-lactamases, or mutations within the KPC-2 family. Given the paucity of information around non-covalent β-lactamase inhibition, we sought to further characterize the specific interactions of a potent, non-covalent CTX-M inhibitor, revealing the importance of amide-π stacking against the β3 backbone (Chapter 2). Building off of this work, we also discovered new non-covalent scaffolds for the inhibition of KPC-2 (Chapters 3 and 4). Our work revealed how the improved hydrophobicity and conformational flexibility of carbapenemases such as KPC-2 can be exploited for building non-covalent affinity, supporting future efforts towards combating emerging resistance