2,997 research outputs found
Introduction: The public health crisis in communist systems
This repository item contains a single article of the Publication Series, papers in areas of particular scholarly interest published from 1989 to 1996 by the Boston University Institute for the Study of Conflict, Ideology, and Policy. The volume this article belongs to is titled "The public health crisis in communist systems"
Cellular delivery of antibodies: effective targeted subcellular imaging and new therapeutic tool
It is already more than a century since the pioneering work of the Nobel Laureate Ehrlich gave birth to the side chain theory1, which helped to define antibodies and their ability to target specific biological sites. However, the use of antibodies is still restricted to the extracellular space due to the lack of a suitable delivery vehicle for the efficient transport of antibodies into live cells without inducing toxicity. In this work, we report the efficient encapsulation and delivery of antibodies into live cells with no significant loss of cell viability or any deleterious affect on the cell metabolic activity. This delivery system is based on poly(2-(methacryloyloxy)ethyl phosphorylcholine)-block-(2-(diisopropylamino)ethyl methacrylate), (PMPC-PDPA), a pH sensitive diblock copolymer that self-assembles to form nanometer-sized vesicles, also known as polymersomes, at physiological pH. These polymersomes can successfully deliver relatively high antibody payloads within live cells. Once inside the cells, we demonstrate that these antibodies can target their epitope by immune-labelling of cytoskeleton, Golgi, and transcription factor proteins in live cells. We also demonstrate that this effective antibody delivery mechanism can be used to control specific subcellular events, as well as modulate cell activity and pro-inflammatory process
Synthesis of well-defined epoxy-functional spherical nanoparticles by RAFT aqueous emulsion polymerization
The environmentally-friendly synthesis of epoxy-functional spherical nanoparticles has been achieved
using polymerization-induced self-assembly (PISA) in aqueous solution. Firstly, a non-ionic hydrophilic
stabilizer block, poly(glycerol monomethacrylate) (PGMA), was prepared by reversible addition–fragmentation
chain transfer (RAFT) solution polymerization in ethanol. This water-soluble precursor was subsequently
chain-extended via RAFT aqueous emulsion polymerization of glycidyl methacrylate (GlyMA) at
50 °C and neutral pH to ensure maximum retention of the epoxy functionality. PISA leads to the formation
of well-defined PGMA-PGlyMA spherical diblock copolymer nanoparticles at up to 35% w/w solids and
1
H NMR spectroscopy studies indicated that virtually all of the epoxy groups survive such relatively mild
conditions. DMF GPC studies confirmed that relatively low dispersities (Mw/Mn < 1.30) were obtained if the
mean degree of polymerization of the core-forming PGlyMA block remained below 100. Well-defined triblock
copolymer nanoparticles could also be prepared via seeded RAFT emulsion polymerization of
n-butyl methacrylate, with DMF GPC analysis indicating a relatively narrow molecular weight distribution
(Mw/Mn < 1.20). The epoxy groups within the nanoparticle cores were ring-opened by adding sodium
azide to a 10% w/w aqueous copolymer dispersion at 50 °C, as confirmed by FT-IR spectroscopy.
PGMA45-PGlyMA100 diblock copolymer nanoparticles could be conveniently converted into cationic
nanogels by utilizing water-soluble diamines as crosslinkers. These nanogels were characterized by DLS
and aqueous electrophoresis and remained intact when dispersed in DMF; in contrast, the corresponding
linear precursor nanoparticles dissociated to form molecularly-dissolved copolymer chains under the
same conditions
Interaction and Expressivity in Video Games: Harnessing the Rhetoric of Film
The film-maker uses the camera and editing creatively, not simply to present the action of the film but also to set up a particular relation between the action and the viewer. In 3D video games with action controlled by the player, the pseudo camera is usually less creatively controlled and has less effect on the player’s appreciation of and engagement with the game. This paper discusses methods of controlling games by easy and intuitive interfaces and use of an automated virtual camera to increase the appeal of games for users
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