Pelagic organisms avoid white, blue, and red artificial light from scientific instruments.

In situ observations of pelagic fish and zooplankton with optical instruments usually rely on external light sources. However, artificial light may attract or repulse marine organisms, which results in biased measurements. It is often assumed that most pelagic organisms do not perceive the red part of the visible spectrum and that red light can be used for underwater optical measurements of biological processes. Using hull-mounted echosounders above an acoustic probe or a baited video camera, each equipped with light sources of different colours (white, blue and red), we demonstrate that pelagic organisms in Arctic and temperate regions strongly avoid artificial light, including visible red light (575-700 nm), from instruments lowered in the water column. The density of organisms decreased by up to 99% when exposed to artificial light and the distance of avoidance varied from 23 to 94 m from the light source, depending on colours, irradiance levels and, possibly, species communities. We conclude that observations from optical and acoustic instruments, including baited cameras, using light sources with broad spectral composition in the 400-700 nm wavelengths do not capture the real state of the ecosystem and that they cannot be used alone for reliable abundance estimates or behavioural studies.

Ocular Medical Devices: Histologic Technique and Histopathologic Evaluation of the Biocompatibility and Performance.

Ocular medical devices (MDs) represent a very wide and promising field of human ophthalmology. In preclinical studies evaluating the safety and/or performance of these ocular MDs, the choice of histologic technique and the focus of the histopathologic evaluation method should take into consideration the following aspects: the specific guidelines possibly associated with the MD or combination product, the ocular compartment in contact with the MD and its specificities, and last the nature of the biomaterial used in the MD. Following a brief overview of animal models, this short review will present the different types of ocular MDs and will present the specificities of the histologic technique and the histopathologic evaluation related to ocular MDs.

[Clinical investigation of the extrusion rate and other complications of the SuperEagle plug].

PURPOSE: Punctal occlusion using a silicone plug is reported as an effective way of treating severe dry eye. The purpose of this study is to investigate the migration, extrusion rate and complications of the SuperEagle plug (Eagle Vision) SUBJECTS AND METHODS: This study involved 148 puncta in 64 eyes of 85 patients (13 eyes of 10 men, 72 eyes of 54 women; mean age: 57.8 +/- 16.6 years [mean +/- standard deviation]) with severe dry eye who underwent punctual occlusion using a SuperEagle plug during the period of May 2009 to September 2010 at our dry eye clinic. We investigated the intracanalicular migration rate, extrusion rate, granulation rate, accumulation of soft whitish material and enlargement of punctum size after extrusion. RESULTS: The migration rate was 0%. The extrusion rate was 57.4% during follow up periods. The average time to extrusion was 92.4 +/- 82.2 days, and the time until 50% of plugs were extruded was 154 days. Granulation was seen in 34.5% of the eyes. 52.9% of puncta that granulation was formed was completely occluded by granulation after extrusion. The accumulation of soft whitish material was not seen in any of the puncta. There was no significant change in the size of the puncta before insertion or after extrusion. CONCLUSION: The insertion of the SuperEagle plug was easy and without intracanalicular migration. Complete punctual occlusion by granulation after extrusion occurred.

Investigation and development of a measurement technique for the spatial energy distribution of home-use intense pulsed light (IPL) systems.

The current annual global market for domestic intense pulse light (IPL) hair removal has been estimated at US $1 billion and continues to grow. The five key technological parameters to consider in cutaneous photo-therapy are wavelength, energy density, pulse duration, spot size and spatial distribution. Uneven energy distribution in the treatment area can result in over or under treatment of the treated area, thus causing dissatisfaction or harmful results. This study investigates a method of measuring and analysing spatial distribution of a number of commercially available home-use IPL systems as there is no quantitative method to conduct and compare spatial distribution at the present. Using a CCD camera and a phosphorescent screen to extend the pulse duration, averaged time frames were analysed using Matlab mathematic software. 3D graphical images of the data are presented to show the spatial profile of five commercially available IPL systems. Numerical analysis of the data was completed by two methods, arithmetical mean roughness and path difference.

Are home-use intense pulsed light (IPL) devices safe?

The domestic market for home-use hair removal devices is rapidly expanding and there are numerous intense pulsed light (IPL) products now available globally to consumers. Technological challenges for the design of such devices include the need to be cost-effective in mass production, easy to use without training, and most importantly, clinically effective while being eye-safe. However inexpensively these light-based systems are produced, they are designed to cause biological damage to follicular structures, so precautions to prevent both ocular and epidermal damage must be considered. At present, there are no dedicated international standards for IPL devices. This review directly compares three leading domestic IPL hair removal devices: iPulse Personal (CyDen, UK), Silk'n/SensEpil (Home Skinovations, Israel), and SatinLux/Lumea (Philips, Netherlands) for fluence, emitted wavelength spectrum, time-resolved footprint, and spatial distribution of energy. Although each device has a primary mechanical or electrical safety feature to ensure occlusion of the output aperture on the skin to prevent accidental eye exposure, the ocular hazard of each device has been measured to IEC TR 60825-9 standard using an Ocean Optics HR2000+ photo spectrometer for both potential corneal and retinal damage. Using established measurement methods, this review has shown that the measured output parameters were significantly different for the three systems. Using equipment traceable to national standards, one device was judged at its two highest settings to be hazardous for naked eye viewing. This investigation also reports on the significantly different pulse durations of the devices measured and considers the potential impact on safety and efficacy in the light of the theory of selective photothermolysis. Although these devices offer low-cost personal convenience of treatment in the privacy of the home, ocular safety may be inadequate in the event of primary safety mechanism failure.