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Perdomo-Ortiz A.,Harvard University | Widom J.R.,University of Oregon | Lott G.A.,Boise Technology Inc. | Aspuru-Guzik A.,Harvard University | Marcus A.H.,University of Oregon
Journal of Physical Chemistry B | Year: 2012

Two-dimensional fluorescence spectroscopy (2D FS) is applied to determine the conformation and femtosecond electronic population transfer in a dimer of magnesium meso tetraphenylporphyrin. The dimers are prepared by self-assembly of the monomer within the amphiphilic regions of 1,2-distearoyl-sn-glycero-3- phosphocholine liposomes. A theoretical framework to describe 2D FS experiments is presented, and a direct comparison is made between the observables of this measurement and those of 2D electronic spectroscopy (2D ES). The sensitivity of the method to varying dimer conformation is explored. A global multivariable fitting analysis of linear and 2D FS data indicates that the dimer adopts a "bent T-shaped" conformation. Moreover, the manifold of singly excited excitons undergoes rapid electronic dephasing and downhill population transfer on the time scale of ∼95 fs. The open conformation of the dimer suggests that its self-assembly is favored by an increase in entropy of the local membrane environment. © 2012 American Chemical Society. Source

Hyatt M.,Boise Technology Inc. | Huang K.,JSR Micro | DeVilliers A.,Tokyo Electron | Slezak M.,JSR Micro | Liu Z.,JSR Micro
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

With extreme UV not ready for HVM for the 20nm and 14nm nodes, double patterning options that extend the use of 193nm immersion lithography beyond the optical resolution limits, such as LELE (Litho-Etch-Litho-Etch) and SADP (Self Aligned Double Patterning), are being used for critical layers for these nodes. LELE requires very stringent overlay capability of the optical exposure tool. The spacer scheme of SADP starts with a conformal film of material around the mandrels and etched along the mandrel sidewalls to form patterns with doubled frequency. SADP, while having the advantage of being a self-aligned process, adds a number of process steps and strict control of the mandrel profile is required. In this paper, we will demonstrate a novel technique - ASDP (Anti-Spacer Double Patterning), which uses only spin-on materials to achieve self-aligned double patterning. After initial resist patterning, an Anti-Spacer Generator (ASG) material is coated on the resist pattern to create the developable spacer region. Another layer of material is then coated and processed to generate the second pattern in between the first resist pattern. We were able to define 37.5nm half pitch pattern features using this technique as well as sub-resolution features for an asymmetric pattern. In this paper we will review the capability of the process in terms of CD control and LWR (line width roughness) and discuss the limitations of the process. © 2014 SPIE. Source

Lott G.A.,Boise Technology Inc. | King M.D.,Boise Technology Inc. | Hill M.W.,Boise Technology Inc. | Scatena L.F.,Boise Technology Inc.
Journal of Physical Chemistry C | Year: 2014

Polyethylenimine (PEI) polymers have become increasingly utilized for a myriad of applications including self-decontaminating materials and nonviral gene transfection. While the bulk properties of PEIs have been studied in detail, their surface-specific structure/behavior remain unexplored. Here, we report the effects of relative humidity on the surface structure of linear polyethylenimine (LPEI), as investigated by vibrational sum frequency generation (VSFG) spectroscopy. Results show that the surface structure of (as prepared) anhydrate LPEI is highly dependent on relative humidity. As the relative humidity is varied from 0% to 75%, surface spectra of LPEI in the C-H and N-H stretching regions reveal multiple crystalline and amorphous states, including the gel-phase amorphous state that has previously only been observed in appreciable quantities above LPEI's upper critical solution temperature (64 °C). Utilizing DFT calculations, we have assigned large characteristic frequency shifts (∼50 cm-1) of LPEI anhydrate crystalline methylene modes to the Bohlmann effect, which is the delocalization of the nitrogen lone electron pair causing a weakening of the C-H bonds of methylene moieties adjacent to the amine functionality. Similar frequency shifts (∼20 cm-1) observed in the hydrated crystalline forms are likely due to intermolecular interactions mediated by hydrogen bonding within the LPEI/water matrix. © 2014 American Chemical Society. Source

Agency: Department of Health and Human Services | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 390.12K | Year: 2009

DESCRIPTION (provided by applicant): The overall goal of this proposal is to develop a non-invasive, real-time, quantifiable cell-based assay to detect and report on furin-like protease activity to identify small molecule inhibitors of furin-like proteases by high throughput screening (HTS). Furin-like proteolytic enzymes are members of the Proprotein Convertase (PC) family that serve to process immature latent proteins, including growth factors and hormones, receptors, plasma proteins, and matrix metalloproteases containing a specific recognition cleavage motif (RX(K/R)R?), to their mature or functional forms. Processing by furin-like protease family members, such as furin, PACE4, PC5/6, and PC7/8, contributes to development of several degenerative diseases, such as Alzheimer's disease, arteriolosclerosis, and arthritis. Furin-like protease expression and activity is necessary for processing substrates that enhance the cancer phenotype, contributing to cell transformation, tumor progression, metastasis, and angiogenesis. Further, furin-like proteolytic processing of viral coat glycoproteins is required for propagation of infectious viruses such as H5N1 avian influenza, HIV-1, human papillomavirus, ebola, yellow fever, and SARS-CoV. Furin-like proteases activate bacterial toxins found in anthrax, shigella, botulinum, pseudomonas, and diphtheria. Inhibition of furin-like proteolytic activity has been shown to halt toxicity of bacterial toxins, infectivity of viruses, and motility of cancer cells. We hypothesize that inhibiting furin-like proteolytic activity may lead to development of a therapeutic drug that inhibits a broad-spectrum of furin-like protease mediated disease. To aid in experimentation of this hypothesis, in specific aim 1A, we will develop a furin-like protease reporter, which non-invasively and quantitatively senses furin-like protease activity in real time and characterize its specificity and sensitivity to furin-like protease activity. In specific aim 1B, we will miniaturize this assay to adapt it to HTS. In specific aim 1C, we will perform HTS of several specialized small molecule libraries containing 71K compounds to identify furin-like protease inhibitory molecules. In specific aim 2A, a secondary screen will be employed to eliminate false positives, cytotoxic, and non-specific inhibitory molecules. Potency will be assessed by exposing the furin-reporter cells to various concentrations of the candidate compound to determine pIC50 values. In specific aim 2B, we subject the five most efficacious compounds to further validation by determining inhibition (IC50 value) of furin processing of physiological substrates using western blot analysis. Additionally, cytotoxicity will be gauged using cell proliferation assays. In specific aim 2C, the compound's ability to inhibit furin will be confirmed using purified furin in vitro. We will also investigate the molecule's specificity by performing in vitro inhibition assays with other serine proteases. At the conclusion of phase I, we expect to have identified at least one compound or derivative with IC50 lt 1uM that will be the subject of further analysis and targeted for drug development to treat furin-mediated diseases such as anthrax and cancer in subsequent years. PUBLIC HEALTH RELEVANCE: Millions of people worldwide are exposed to and/or contract furin-like protease mediated diseases such as HIV-1, ebola, avian influenza, human papillomavirus, yellow fever, SARS-CoV, anthrax, botulinum, measles, pseudomonas, shigella, diphtheria, arthritis, arteriosclerosis, Alzheimer's disease, and malignant cancer. Instead of searching for a therapeutic to address each pathogen and disease individually, targeting a single cellular protease may allow defeat of a broad spectrum of furin-like protease mediated disease. The studies described here will result in identification of a molecule that inhibits furin-like proteases and thus may be used to treat the diseases listed above.

King M.D.,Boise Technology Inc. | Kihara M.T.,Boise Technology Inc. | Lott G.A.,Boise Technology Inc. | Hill M.W.,Boise Technology Inc. | Scatena L.F.,Boise Technology Inc.
Journal of Physical Chemistry C | Year: 2014

Functionalized self-assembled monolayers (SAMs) are of interest for numerous applications including materials for national security and defense, chemical and biological sensing, and electronic device components. Understanding the surface structures of SAMs is important for determining the functionality and efficiency of these systems and aiding in the design of advanced materials. In this study, the surface structures of amine-bearing siloxane SAMs on fused silica were investigated by vibrational sum frequency generation (VSFG) spectroscopy and density functional theory (DFT). VSFG spectra of the SAMs were collected in the C-H and N-H stretching regions, and observed spectral features were assigned to specific vibrational modes that provided information regarding the surface structure of the deposited SAM. The molecular conformation of secondary amine moieties was determined to have a significant effect on the vibrational frequencies of methylene vibrational modes. Red-shifting of the methylene symmetric stretching mode by greater than 50 cm-1 was observed experimentally in systems containing secondary amines. This effect was confirmed by DFT calculations and found to be a consequence of molecular conformation that allowed the formation of resonance structures depending on the position of the nitrogen lone-pair electrons with respect to C-N and C-H bonding and antibonding orbitals, respectively. © 2014 American Chemical Society. Source

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