Whitworth University

Diffractive deep neural networks (DDNNs) are free-space optical image processors that can perform image classifications. Integrated DDNNs can be directly fabricated on detectors with two-photon polymerization (TPP). This publication discusses some of the numerical and fabrication limitations that govern the design of integrated DDNNs for near-infrared (NIR) and visible wavelengths. Numerical optimization and simulation results are presented for an example geometry that can be fabricated with TPP printing.

Purpose -The purpose of this study is to frame the value of library patron privacy in terms of Kantian ethics, providing a justification of why patron privacy should be protected that may be persuasive beyond the library community, particularly in a United States policy context. Design/methodology/approach -This study employs ethical reasoning, applying an ethical framework to specific cases. Findings -This study finds that Kantian ethics provides compelling reasons why patron privacy should be protected, especially that the Formula of Humanity requires that patrons provide meaningful consent for the use of their information, and that Kant's conception of innate right justifies the library community in advocating for public policies that protect patron privacy. Originality/value -While the discourse of professional ethics in library and information science often acknowledges Kantian ethics in a general way, studies that apply the framework to specific cases are rare. This is the first study that uses Kantian ethics to provide justification for patron privacy protections.

Well-defined, small-molecule, platinum-centered coordination compounds are of continued interest in both basic and applied research, particularly in medicinal chemistry and pharmaceuticals (i.e., cisplatin). Organoplatinum(IV) complexes have been reported to exhibit substantial in vitro cytotoxicity across a range of cancer cell lines. Compared with coordinatively unsaturated platinum(II) species, electronically and coordinatively saturated platinum(IV) complexes are generally more inert, reducing undesirable side reactions in plasma and cellular environments and potentially improving their safety profiles as chemotherapeutic agents. In addition, the presence of organic ligands can enhance lipophilicity, facilitating passive diffusion across cell membranes. Here, we report the synthesis, structural characterization, and in vitro anticancer activity of a series of organoplatinum(IV) complexes of the general formula Pt(CH3)2I2{n,n′-dimethyl-2,2′-bipyridine} (n,n′ = 4,4′; 5,5′; 6,6′). The 5,5′- and 6,6′-dimethyl isomers were characterized by single-crystal X-ray diffraction. All three dimethyl-substituted complexes, along with the parent compound, Pt(CH3)2I2{2,2′-bipyridine}, were evaluated for cytotoxic activity against a panel of 60 human cancer cell lines. Whereas Pt(CH3)2I2{2,2′-bipyridine} and the 4,4′- and 5,5′-dimethyl derivatives displayed limited cytotoxicity, the 6,6′-dimethyl isomer exhibited notable activity, particularly against the colon cancer cell line HCT-116 (LC50 = 8.17 μM) and the ovarian cancer cell line OVCAR-3 (LC50 = 7.34 μM). The enhanced cytotoxicity of the 6,6′-dimethyl derivative is attributed, at least in part, to the relatively facile dissociation of the 6,6′-dimethyl-2,2′-bipyridine ligand from the platinum(IV) center, suggesting that sterically induced ligand lability plays an important role in modulating biological activity in this particular compound, giving new structural activity impetus for potential drug molecules.

Contact mediated cell-cell communication where direct physical contact between adjacent ligand cells and receptor cells trigger signal output is important during growth, development and regeneration of organisms. While the molecular machinery underlying contact mediated cell signaling is well explored, how the local spatial context of cells affect cell-cell contact mediated gene expression is not clear. Here, we present a vertex-based computational model to study spatial and temporal behavior of contact mediated signal output (which we refer to as output) in growing cell collectives. We consider cell-cell contact length dependent output synthesis and output degradation in receptor cells together with cell division to understand how dynamics at the scale of single cells lead to heterogeneous signal output. By tracking single receptor cells over time in growing cell collectives in silico , we show that cell growth and division lead to continuous and dynamic rearrangement of cell-cell contact between receptor and ligand cells which in turn affect the output levels. Our model predicts that the orientation of cell division plays a key role in the heterogeneity of signal output. We elucidate the link between cell mechanical properties that control cell shape, growth, and division, with signal output in receptor cells during contact mediated signaling processes.