Laustsenfuentes4859

We study the EDL force between two colloidal particles that are adsorbed to the surface of an electrolyte solution. The attachment of colloidal particles to a free surface of an electrolyte solution, which may interface with another liquid or vapor phase, is a well-known phenomenon that is employed in many scientific and industrial applications; the most well known of which is the Pickering emulsion. In addition to capillary stresses, the particles will experience an electrical double layer (EDL) force when they are close to each other. The force originates from the overlap of the diffusive layers of ions that appear in the electrolyte solution next to the charged surfaces of the particles and the charged surface of the electrolyte solution, which is free of particles. Here we elucidate the contribution of the free surface of the electrolyte solution to the EDL force between two spherical particles, which are half-submerged in the electrolyte solution. We solve the linearized Poisson-Boltzmann equation for the excess electrical potential near the particles and integrate over the resulting excess Maxwell and osmotic stresses on the particles. We further give corresponding P\'ade approximations, thus enabling the use of simple formulae for the EDL force between interacting particles in cases similar to the ones in this study without the need to repeat the mathematical procedure employed here.Differences in the physical interaction between proteins, such as binding equilibria, can provide clues to differences in function. The binding of heat shock proteins to substrate proteins in living cells is such a case. Eukaryotic cells have evolved many homologs in the Hsp70 family of heat shock proteins, each specialized for a specific function. We previously showed that Hsp70, which is up-regulated during heat shock, binds the model substrate phosphoglycerate kinase (PGK) in human cells before PGK completely unfolds. We dubbed this the 'preemptive holding' mechanism. Here we study the homolog Hsc70 (heat shock cognate protein), which is constitutively expressed in human cells even in the absence of heat shock. Recent literature has demonstrated multiple functions performed by Hsc70 in cells under normal conditions. Despite the name 'heat shock cognate,' very few studies have shown whether Hsc70 is actually involved in heat shock response. Here we corroborate the existence of an in-cell heat shock response of Hsc70. We show that Hsc70 binds PGK in human cells in a cooperative manner that correlates directly with protein thermal unfolding. This 'unfolded state holding' mechanism differs from the Hsp70 'preemptive holding' mechanism. We rationalize the difference by protein evolution unlike Hsp70, which is upregulated to bind proteins specifically during heat shock, the finite amount of Hsc70 in cells cannot bind to still-folded proteins, or its multiple other functions would be compromised.Substitutional doping lanthanide ions (Ln3+) in CsPbX3 has been proven to be an efficient strategy for expanding the properties of the perovskite (PVK). Here, erbium (Er3+) uniformly doped CsPbX3 perovskite microplates are grown through a chemical vapor deposition method. Two fluorescence peaks at 430 and 520 nm which respectively correspond to the PVK and Er3+ emissions are observed. The time-resolved photoluminescence of both PVK host and Er dopants demonstrates that trap states play a critical role in facilitating the energy transfer between the PVK host and the Er dopants, which is vital to sensitizing the Er3+. A photophysical model was put forward to comprehensively describe this trap-mediated energy-transfer process, and the dynamics processes are modeled using correlated rate equations. The rates of the carrier's relaxation and energy transfer are respectively obtained as 6.6 and 49 ns-1, and a total energy transfer efficiency was obtained as ∼32.6%.Plasmonic nanostructures overcome Abbe's diffraction limit to create strong gradient electric fields, enabling efficient optical trapping of nanoparticles. However, it remains challenging to achieve stable trapping with low incident laser intensity. Here, we demonstrate Fano resonance-assisted plasmonic optical tweezers for single nanoparticle trapping in an array of asymmetrical split nanoapertures on a 50 nm gold thin film. A large normalized trap stiffness of 8.65 fN/nm/mW for 20 nm polystyrene particles at a near-resonance trapping wavelength of 930 nm was achieved. The trap stiffness on-resonance is enhanced by a factor of 63 compared to that of off-resonance due to the ultrasmall mode volume, enabling large near-field strengths and a cavity effect contribution. These results facilitate trapping with low incident laser intensity, thereby providing new options for studying transition paths of single molecules such as proteins.The fundamentals of using cracked film lithography (CFL) to fabricate metal grids for transparent contacts in solar cells were studied. The underlying physics of drying-induced cracks were well-predicted by an empirical correlation relating crack spacing to capillary pressure. 8-OH-DPAT CFL is primarily controlled by varying the crack template thickness, which establishes a three-way tradeoff between the areal density of cracks, crack width, and spacing between cracks, which in turn determine final grid transmittance, grid sheet resistance, and the semiconductor resistance for a given solar cell. Since CFL uses a lift-off process, an additional constraint is that the metal thickness must be less than 1/3 of the crack template thickness. The transmittance/grid sheet resistance/wire spacing tradeoffs measured in this work were used to calculate solar cell performance CFL-patterned grids should outperform screen-printed grids for narrow cells (0.5-2 cm wide) and/or cells with high semiconductor sheet resistance (≥100 Ω/sq), making CFL attractive for monolithically integrated thin-film photovoltaic modules.The accumulation of 99mTc-labeled probes targeting saturable systems of the body is hindered by the presence of a large excess of unlabeled ligands needed to ensure high radiochemical yields in a short reaction time. To address the issue, we recently reported a novel concept of a metal-coordination-mediated synthesis of a bivalent 99mTc-labeled probe from a monovalent ligand using d-penicillamine (Pen) as a chelating molecule and c(RGDfK) as a model targeting device. The Pen-conjugated c(RGDfK) via a hexanoate linkage (Pen-Hx-c(RGDfK)) provided a bivalent [99mTc]Tc-[(Pen-Hx-c(RGDfK))2 that possessed much higher integrin αvβ3 binding affinity than Pen-Hx-c(RGDfK) and visualized a murine tumor without purification. However, high radioactivity levels were observed in the abdominal regions, which necessitated improved pharmacokinetics of the probes for practical applications. In this study, a pharmacokinetic (PK) modifier was introduced to manipulate the pharmacokinetics of the 99mTc-Pen2-based bivalent probe. The Hx linkage in Pen-Hx-c(RGDfK) was replaced with acetyl-d-serine-d-serine-glycine (Ac-ssG) or hexanoyl-d-serine-d-serine-d-serine (Hx-sss) to prepare Pen-Ac-ssG-c(RGDfK) or Pen-Hx-sss-c(RGDfK).