45 research outputs found
Interactions Between Charged Rods Near Salty Surfaces
Using both theoretical modeling and computer simulations we study a model
system for DNA interactions in the vicinity of charged membranes. We focus on
the polarization of the mobile charges in the membranes due to the nearby
charged rods (DNA) and the resulting screening of their fields and inter-rod
interactions. We find, both within a Debye-Huckel model and in Brownian
dynamics simulations, that the confinement of the mobile charges to the surface
leads to a qualitative reduction in their ability to screen the charged rods to
the degree that the fields and resulting interactions are not finite-ranged as
in systems including a bulk salt concentration, but rather decay algebraically
and the screening effect is more like an effective increase in the multipole
moment of the charged rod
The Arctic as Emerging Geopolitical Flashpoint Proceedings of the 45th Canada-United States Law Institute Annual Conference - Climate Change and the Arctic: Profound Disruption, Uncertain Impact
Charge Fluctuations on Membrane Surfaces in Water
We generalize the predictions for attractions between over-all neutral
surfaces induced by charge fluctuations/correlations to non-uniform systems
that include dielectric discontinuities, as is the case for mixed charged lipid
membranes in an aqueous solution. We show that the induced interactions depend
in a non-trivial way on the dielectric constants of membrane and water and show
different scaling with distance depending on these properties. The generality
of the calculations also allows us to predict under which dielectric conditions
the interaction will change sign and become repulsive
Enabling a More Externally Focused and Operational PLA – 2020 PLA Conference Papers
Although the People’s Liberation Army is not yet a global expeditionary force on par with the US military, the former has nevertheless significantly expanded its ability to operate abroad. Through enhanced technological capabilities, robust relationships with foreign militaries, increased access to overseas military bases and dual-use facilities, and the implementation of major structural reforms, the People’s Liberation Army has built a more integrated joint force capable of conducting a wider and more complex array of missions. This volume advances the understanding of the People’s Liberation Army’s capability to conduct overseas missions by examining China’s military relations with Europe, Africa, and Latin America; the country’s military activities in the Indian Ocean, polar regions, and Pacific Island countries; and the emerging roles of the People’s Liberation Army Rocket Force and the Joint Logistic Support Force. This volume finds the People’s Liberation Army is engaged in a wide range of activities throughout the world, including port calls, joint exercises, seminars, and personnel exchanges. China sells weapons to some parts of the world and seeks to acquire military and dual-use technology from others. In addition, the People’s Liberation Army seeks to increase its capability to operate in parts of the world, such as the Indian Ocean, Pacific Island countries, and polar regions, where the organization has only had a minimal presence in the past.https://press.armywarcollege.edu/monographs/1947/thumbnail.jp
Assessment of reproducibility of matrix-assisted laser desorption ionization - Time of flight mass spectrometry for bacterial and yeast identification
Matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry (MS) has revolutionized the identification of clinical bacterial and yeast isolates. However, data describing the reproducibility of MALDI-TOF MS for microbial identification are scarce. In this study, we show that MALDI-TOF MS-based microbial identification is highly reproducible and can tolerate numerous variables, including differences in testing environments, instruments, operators, reagent lots, and sample positioning patterns. Finally, we reveal that samples of bacterial and yeast isolates prepared for MALDI-TOF MS identification can be repeatedly analyzed without compromising organism identification
PNC-27, a Chimeric p53-Penetratin Peptide Binds to HDM-2 in a p53 Peptide-like Structure, Induces Selective Membrane-Pore Formation and Leads to Cancer Cell Lysis
PNC-27, a 32-residue peptide that contains an HDM-2 binding domain and a cell-penetrating peptide (CPP) leader sequence kills cancer, but not normal, cells by binding to HDM-2 associated with the plasma membrane and induces the formation of pores causing tumor cell lysis and necrosis. Conformational energy calculations on the structure of PNC-27 bound to HDM-2 suggest that 1:1 complexes form between PNC-27 and HDM-2 with the leader sequence pointing away from the complex. Immuno-scanning electron microscopy was carried out with cancer cells treated with PNC-27 and decorated with an anti-PNC-27 antibody coupled to 6 nm gold particles and an anti-HDM-2 antibody linked to 15 nm gold particles. We found multiple 6 nm- and 15 nm-labeled gold particles in approximately 1:1 ratios in layered ring-shaped structures in the pores near the cell surface suggesting that these complexes are important to the pore structure. No pores formed in the control, PNC-27-treated untransformed fibroblasts. Based on the theoretical and immuno-EM studies, we propose that the pores are lined by PNC-27 bound to HDM-2 at the membrane surface with the PNC-27 leader sequence lining the pores or by PNC-27 bound to HDM-2
Understanding how primary care practitioners perceive an online intervention for the management of hypertension
Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures
Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo