There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

Fast parallel algorithms for short-range molecular dynamics

Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology.

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Self-assembled monolayers of thiolates on metals as a form of nanotechnology.

Fundamentals of Plasmonics.- Electromagnetics of Metals.- Surface Plasmon Polaritons at Metal / Insulator Interfaces.- Excitation of Surface Plasmon Polaritons at Planar Interfaces.- Imaging Surface Plasmon Polariton Propagation.- Localized Surface Plasmons.- Electromagnetic Surface Modes at Low Frequencies.- Applications.- Plasmon Waveguides.- Transmission of Radiation Through Apertures and Films.- Enhancement of Emissive Processes and Nonlinearities.- Spectroscopy and Sensing.- Metamaterials and Imaging with Surface Plasmon Polaritons.- Concluding Remarks.

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Plasmonics: Fundamentals and Applications

Template-Assisted Antibody Assembly: A Versatile Approach for Engineering Functional Antibody Nanoparticles

The interaction between surface plasmon resonance of the metallodielectric photonic crystal and the Bragg resonance of the opal photonic crystal has been studied. Two types of samples were investigated, differing in the topology of the metal content, metal-dielectric photonic crystals prepared using layer-by-layer deposition coating spheres with oppositely charged polyelectrolyte and Au nanoparticles and infiltrated opaline structures with Au nanoparticles. It was found that when the“red”-shift of plasmon resonance overlaps the Bragg diffraction, the latter become almost disperionless.

Towards 3D metal-dielectric photonic crystal. Optical characterization

The present invention relates to capsules, and the method for making such capsules, having a boronate linked organic network layer comprising (a) a plurality of boronic acid containing moieties and (b) a plurality of galloyi linking moieties, which capsules are responsive to externally applied stimuli, for applications including cell encapsulation, advanced drug delivery, biomedical diagnostics, micro-reactions, and the formation of biomimetic protocells.

Glucose sensitive phenylborate acid capsules for insulin delivery

Capsules (I) having a polyelectrolyte (PE) shell and a diameter of up to 10 (preferably to 5) Microm, are new, specifically where (I) are obtained by applying PE molecules onto template particles (II). Independent claims are included for the following: (1) the preparation of (I) (with no restriction on capsule size) by forming an aqueous dispersion of (II) having suitable size, then applying PE to (II); (2) the preparation of a coated surface by applying (I) to the surface; (3) partially crosslinked melamine-formaldehyde (MF) particles (III) having a diameter of 10 Microm or less; (4) the preparation of partially crosslinked MF particles by polycondensation of MF precondensates, where the polycondensation process is interrupted during the reaction; and (5) a method for applying multiple coating layers to (II), involving: (a) contacting (II) with a first coating material (C1) in a liquid medium, in a reaction region bounded on at least one side by a filtration membrane, to form a coating of (C1) on (II); (b) removing at least part of the reaction medium, optionally with any excess (C1), via the filtration membrane; (c) repeating steps (a) and (b), but using a second coating material (C2) instead of (C1); and (d) optionally repeating steps (a)/(b) and/or step (c).

Capsules comprising lipids in the coating

Engineering reactive and functional nanostructured surfaces is important for enhancing the sensitivity and versatility of biosensors and microreactors. For example, the assembly of hybrid inorganic–organic porous microparticles on surfaces may provide a catalytic microenvironment for a wide range of reactions. Herein, the synthesis of catalytically active porous dextran sulfate–copper phosphate hybrid microparticles by a facile and rapid crystallization process in aqueous solution is reported. The sulfated polysaccharide enables control over the size and hierarchical morphology of the hybrid microparticles, as well as their assembly into stable macroporous coatings. The engineered microparticle coatings display intrinsic nonenzymatic peroxidase‐like catalytic activity when employed as a platform for the detection of hydrogen peroxide. Pairing of the microparticle coating with glucose oxidase affords a hybrid platform that is employed as a glucose sensor for monitoring physiological concentrations of a given analyte via a hybrid enzymatic/nonenzymatic cascade reaction. This work presents a strategy for the assembly of hybrid porous microparticles into enzyme‐mimicking surfaces for copper‐based catalysis and biochemical analyte sensing.

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Frank Caruso

Papers

Template-Assisted Antibody Assembly: A Versatile Approach for Engineering Functional Antibody Nanoparticles

Towards 3D metal-dielectric photonic crystal. Optical characterization

Glucose sensitive phenylborate acid capsules for insulin delivery

Capsules comprising lipids in the coating

Catalytically Active Copper Phosphate–Dextran Sulfate Microparticle Coatings for Bioanalyte Sensing