Publications by authors named "Robert Vasquez"

A detailed framework for modeling and interpreting the data in totality from a cyclic voltammetric measurement of adsorbed redox monolayers on semiconductor electrodes has been developed. A three-layer model consisting of the semiconductor space-charge layer, a surface layer, and an electrolyte layer is presented that articulates the interplay between electrostatic, thermodynamic, and kinetic factors in the electrochemistry of a redox adsorbate on a semiconductor. Expressions are derived that describe the charging and faradaic current densities individually, and an algorithm is demonstrated that allows for the calculation of the total current density in a cyclic voltammetry measurement as a function of changes in the physical properties of the system (e.

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A framework for interpreting the cyclic voltammetric responses from adsorbed redox monolayers on semiconductor electrodes has been developed. Expressions that describe quantitatively how the rates of the forward and back charge-transfer reactions impact the faradaic current density are presented. The primary insight is an explicit connection between the potential drops across the semiconductor space charge, surface, and electrolyte diffuse layers and the potential dependence of the reaction kinetics.

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Background: Renal medullary carcinoma (RMC) is a very rare, aggressive neoplasm occurring almost exclusively in adolescents and young adults with sickle cell trait. Given the rare nature of this tumor, accounting for less than 0.5% of all renal carcinomas, most of the published data on therapies is from case reports and small case series, and current treatments are insufficient, with most patients succumbing to their disease in months.

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An examination of the efficacy of combining physisorbed and chemisorbed passivation strategies on crystalline Si has been performed. This report compares the influence of a linear alkyl adsorbate tethered by either a Si-C or Si-Si linkage, prepared by reaction of Si(111) with organometallic Grignard reagents or organosilanes, respectively. These modified surfaces are first analyzed and compared by IR and X-ray photoelectron spectroscopies.

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Acute myeloid leukemia (AML) is a heterogenous group of diseases affecting ~500 children in the United States annually. With current therapy, 90% of these children will obtain complete remission. However, 30% to 40% of these patients will relapse, most commonly within the first 3 years.

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Hydrogenation reactions can be used to store energy in chemical bonds, and if these reactions are reversible, that energy can be released on demand. Some of the most effective transition metal catalysts for CO hydrogenation have featured pyridin-2-ol-based ligands (e.g.

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We report the synthesis and characterization of new ruthenium(II) and iridium(III) complexes of a new bidentate chelate, NHC-py (OR = OMe, OtBu, OH and R' = Me, Et). Synthesis and characterization studies were done on the following compounds: four ligand precursors (1-4); two silver complexes of these NHC-py ligands (5-7); six ruthenium complexes of the type [η-(p-cymene)Ru(NHC-py)Cl]X with R' = Me, Et and R = Me, tBu, H and X = OTf, PF and POF (8-13); and two iridium complexes, [Cp*Ir(NHC-py)Cl]PF (14) and [Cp*Ir(NHC-py)Cl]POF (15). The complexes are air stable and were isolated in moderate yield.

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Objective: Lichen sclerosus (LS) is a chronic progressive inflammatory autoimmune-induced disease that primarily affects the epidermis and dermis of the external genital-anal region. Intense and recalcitrant pruritus is the hallmark of LS. Physical exam reveals thinning, hyperkeratosis, and parchment-like appearance.

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A three-year-old boy presented with an enlarging neck mass. Biopsy demonstrated IgD-positive nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL), which was staged as IIa. The patient received cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) with rituximab and had excellent results.

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Here we demonstrate that Arp2/3 regulates a transition between mesenchymal and amoeboid protrusions in MCF10A epithelial cells. Using genetic and pharmacological means, we first show Arp2/3 inhibition impairs directed cell migration. Arp2/3 inhibition results in a dramatically impaired cell adhesion, causing deficient cell attachment and spreading to ECM as well as an 8-fold decrease in nascent adhesion assembly at the leading edge.

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