The photophoretic force is described by a comprehensive model containing aspects of both the optical local-field and gas-dynamic properties. It is shown that the model is in good agreement with detailed experimental data and provides a new means for measuring optical constants of microparticles.

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We review the essential physics of microparticle electrodynamic ion traps (MEITs) and suggest several improvements in the design, construction, and application of MEITs in undergraduate physics teaching. Pulling together insights gleaned from a number of disparate sources, we have developed MEITs with better overall performance and reliability in comparison to previous publications. This work b...

background: it has been known that brain-derived neurotrophic factor (bdnf) is involved in neural survival and long term memory (ltm). here we hypothesized that bdnf as a potent neurotrophic factor might modulate amnestic effect induced by morphine. objectives: the aim of this study was to examine whether infusion of exogenous bdnf in the ca1 regions of the dorsal hippocampi could ameliorate me...

abstract background: measures to protect the public following an accidental release of radionuclides to the environment will depend on the circumstances including the extent of the potential hazards. the projected levels of risk are an important precondition in emergency planning. the levels can be expressed in terms of concentration levels in the environment or in foodstuffs. these derived int...

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1. Department of Experimental Biology, Faculty of Medicine of Porto, University of Porto, Portugal; IBMCInstituto de Biologia Molecular e Celular, Universidade do Porto, Portugal., 2. Molecular Neurobiology Unit, University of Bristol, CSSB, Dorothy Hodgkin Building, Bristol, UK, 3. Department of Urology, Hospital de S. João, Porto, Portugal; IBMCInstituto de Biologia Molecular e Celular, Unive...

We present a novel device for the separation of microparticles in a single channel, which is made of inversely asymmetric Brownian ratchets. It enables separation into two different fractions with an adjustable threshold and can be modeled with good agreement. This device serves as proof of concept for an extremely compact class of microsieves.