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Micro (Greek letter μ, mu) is a unit prefix in the metric system denoting a factor of 10−6 (one millionth). Confirmed in 1960, the prefix comes from the Greek μικρός (mikrós), meaning "small". It is the only SI prefix which uses a character not from the Latin alphabet. In Unicode, the symbol is represented by or the legacy symbol . The prefix "mc" is commonly used in healthcare or when the character "μ" is not available; for example, "mcg" commonly denotes a microgram. The letter u is sometimes used instead of μ when non-Latin characters are not available. Examples

Typical bacteria are 1 to 10 micrometer (1–10 µm) in diameter.
Eukaryotic cells are typically 10 to 100 micrometers in diameter.

Symbol encoding in character sets The official symbol for the SI prefix micro is a Greek lowercase mu (μ). For reasons stemming from its design, Unicode has two different character codes for the letter, with slightly different appearance in some f

Electrophoretic deposition of multi-scale structured TiO2 surfaces

The long term fixation of biomedical implants constitutes an issue in the clinical praxis. Implant fixation can be improved by functionalizing its surface. In fact, the tissue response around an implant is conditioned by its surface morphological and chemical properties. Coatings for implants (orthopedic and dental) function at the bone-implant fixation interface. As proved by research activities in the biomedical field, coatings with topographic features in the nano- and micro-range are promising in terms of enhanced osteointegration, thus improved implant fixation. As for surface chemistry, titanium dioxide (TiO2) is an estabilished material for biomedical implants thanks to its outstanding physical and chemical properties such as high corrosion resistance and good biocompatibility. Electrophoretic deposition (EPD) is a simple and versatile coating technique. According to literature, EPD is an emerging potential coating technique for biomedical implants. In this work, the use of EPD in the preparation of TiO2 coatings characterized by a controlled multi-scale structured surface was addressed. For this aim, EPD was combined with a new procedure of particle functionalization and with the use of a fugitive spacer (polystyrene, PS) for the sintering treatment. A control and better understanding of the EPD process were achieved through a preliminary parametric study on EPD of TiO2 nanoparticles and PS microbeads. Particle concentration was found to play a key role in the EPD deposit formation of TiO2 nanoparticles (cathodic) and PS microbeads (anodic). A threshold value of particle concentration was identified, below which no deposit growth occurred. An interpretation of this finding was provided on the base of a new formulation of the EPD deposition mechanism. The results of the particle concentration study contributed to the preparation of suspensions with TiO2-PS composite particles, which could be used for cathodic EPD. Composite TiO2-PS particles with TiO2 nanoparticles covering PS microbeads were obtained in a newly developed wet colloidal process based on heterocoagulation and the use of polyelectrolytes. The resulting TiO2-PS particles were cathodically deposited on Ti6Al4V substrates. A sintering post-treatment caused the burning out of the PS beads and the densification of the TiO2 nanoparticles. The desired coatings with controlled micro- and nano-topography were achieved. The investigation on the role of particle concentration in EPD and the new interpretation of the deposition mechanism bring a deeper understanding of the EPD process. The achievement of TiO2 coatings with controlled morphology in the micro- and nano-range prepared by cathodic EPD on Ti6Al4V substrates is a contribution to the ongoing research on biomedical implants. Mechanical tests and surface analysis evaluating wettability and in vitro cell behavior with the achieved coatings are relevant topics for further research.

EPFL2009

IP Strategy and Use Of IP Protection Mechanisms Across Firm Size: An empirical investigation

Tilo Peters, Jana Thiel

In this paper we use data from the 2012 Innovation Strategy Survey (485 responses) to compare motives and choices with respect to IP strategy in firms with sizes ranging from micro to very large. Our results confirm significant differences across firm size when it comes to strategic goals, availability of means to deal with open innovation environments, the ability to generate licensing revenues, as well as the in the practice and motivations for the use of non-patenting disclosure. We find, for example, that the potential of licensing as a means of appropriating value only holds in the context of the very large firms, which has implications for the IP strategy of smaller actors. Likewise, we also begin to see a pattern emerging concerning the openness of firms’ innovation strategy wherein the extremes of the firm-size scale tend to express similar behavior but for apparently different reasons; thus they apply differing IP strategies. By our interpretation, smaller firms exhibit a predominant preference for open IP strategies while very large firms tend to exhibit more closed IP strategies. We also find that the majority of firms—in particular micro-sized firms—is interested in securing freedom to operate. This provides further reason for us to believe that the practice of strategic disclosure—a competitive and cost effective means to enhance freedom to operate—is underrepresented in awareness and use within integrated IP strategies.

2016

Structured nanoscale metallic glass fibres with extreme aspect ratios

Grégoire Courtine, Reinis Ignatans, Nicholas David James, Güven Kurtuldu, Stéphanie Lacour, Dang Tùng Nguyen, Yunpeng Qu, Inès Richard, Giuseppe Schiavone, Fabien Sorin, Jordan Squair, Vasiliki Tileli, Wei Yan

Micro- and nanoscale metallic glasses offer exciting opportunities for both fundamental research and applications in healthcare, micro-engineering, optics and electronics. The scientific and technological challenges associated with the fabrication and utilization of nanoscale metallic glasses, however, remain unresolved. Here, we present a simple and scalable approach for the fabrication of metallic glass fibres with nanoscale architectures based on their thermal co-drawing within a polymer matrix with matched rheological properties. Our method yields well-ordered and uniform metallic glasses with controllable feature sizes down to a few tens of nanometres, and aspect ratios greater than 10(10). We combine fluid dynamics and advanced in situ transmission electron microscopy analysis to elucidate the interplay between fluid instability and crystallization kinetics that determines the achievable feature sizes. Our approach yields complex fibre architectures that, combined with other functional materials, enable new advanced all-in-fibre devices. We demonstrate in particular an implantable metallic glass-based fibre probe tested in vivo for a stable brain-machine interface that paves the way towards innovative high-performance and multifunctional neuro-probes. Metallic glasses possess intriguing functional properties, but controlled fabrication with nanoscale feature sizes remains challenging. Thermal co-drawing within a viscosity-matched polymer matrix enables the fabrication of uniform metallic glass fibres with feature sizes down to a few tens of nanometres, arbitrary transverse geometries and aspect ratios greater than 10(10).

NATURE PUBLISHING GROUP2020

Electrophoretic deposition of multi-scale structured TiO2 surfaces

EPFL2009