A retinal origin of nystagmus—a perspective

Congenital nystagmus is a condition where the eyes of patients oscillate, mostly horizontally, with a frequency of between 2 and 10 Hz. Historically, nystagmus is believed to be caused by a maladaptation of the oculomotor system and is thus considered a disease of the brain stem. However, we have recently shown that congenital nystagmus associated with congenital stationary night blindness is caused by synchronously oscillating retinal ganglion cells. In this perspective article, we discuss how some details of nystagmus can be accounted for by the retinal mechanism we propose

Flat oyster pilot design in North Sea offshore wind farm

Motivation flat oyster pilot in wind farms. Flat oyster beds provide natural hard-substrate habitat in a predominantly soft-bottom marine environment. In addition, they change environmental conditions by filtering, nutrient recycling and carbon storage. Hence, North Sea marine life, probably even including fish production, will increase when flat oyster beds are restored. Since bottom-trawling fishery is excluded in wind farms, an essential condition for flat oyster restoration is fulfilled here. Basic conditions for flat oyster growth and reproduction, such as food availability, sediment composition and sea floor stability, are also met in several wind farms off the Dutch coast. Hence, flat oyster restoration in wind farms constitutes a potential marine biodiversity enrichment opportunity. The current report provides key information on design, deployment, monitoring and final removal of a flat oyster restoration pilot in a wind farm in the Dutch part of the North Sea

A common cause for nystagmus in different congenital stationary night blindness mouse models

In Nyxnob mice, a model for congenital nystagmus associated with congenital stationary night blindness (CSNB), synchronous oscillating retinal ganglion cells (RGCs) lead to oscillatory eye movements, i.e. nystagmus. Given the specific expression of mGluR6 and Cav1.4 in the photoreceptor to bipolar cell synapses, as well as their clinical association with CSNB, we hypothesize that Grm6nob3 and Cav1.4-KO mutants show, like the Nyxnob mouse, oscillations in both their RGC activity and eye movements. Using multi-electrode array recordings of RGCs and measurements of the eye movements, we demonstrate that Grm6nob3 and Cav1.4-KO mice also show oscillations of their RGCs as well as a nystagmus. Interestingly, the preferred frequencies of RGC activity as well as the eye movement oscillations of the Grm6nob3, Cav1.4-KO and Nyxnob mice differ among mutants, but the neuronal activity and eye movement behaviour within a strain remain aligned in the same frequency domain. Model simulations indicate that mutations affecting the photoreceptor–bipolar cell synapse can form a common cause of the nystagmus of CSNB by driving oscillations in RGCs via AII amacrine cells. (Figure presented.). Key points: In Nyxnob mice, a model for congenital nystagmus associated with congenital stationary night blindness (CSNB), their oscillatory eye movements (i.e. nystagmus) are caused by synchronous oscillating retinal ganglion cells. Here we show that the same mechanism applies for two other CSNB mouse models – Grm6nob3 and Cav1.4-KO mice. We propose that the retinal ganglion cell oscillations originate in the AII amacrine cells. Model simulations show that by only changing the input to ON-bipolar cells, all phenotypical differences between the various genetic mouse models can be reproduced.</p

Flat oyster pilot design in North Sea offshore wind farm

Motivation flat oyster pilot in wind farms. Flat oyster beds provide natural hard-substrate habitat in a predominantly soft-bottom marine environment. In addition, they change environmental conditions by filtering, nutrient recycling and carbon storage. Hence, North Sea marine life, probably even including fish production, will increase when flat oyster beds are restored. Since bottom-trawling fishery is excluded in wind farms, an essential condition for flat oyster restoration is fulfilled here. Basic conditions for flat oyster growth and reproduction, such as food availability, sediment composition and sea floor stability, are also met in several wind farms off the Dutch coast. Hence, flat oyster restoration in wind farms constitutes a potential marine biodiversity enrichment opportunity. The current report provides key information on design, deployment, monitoring and final removal of a flat oyster restoration pilot in a wind farm in the Dutch part of the North Sea

Shellfish bed restoration pilots Voordelta, Netherlands : Annual report 2018

The general objectives of the shellfish bed restoration pilots in the Voordelta are: to select suitable locations for shellfish bed restoration, identify critical factors for shellfish bed development, develop methods for shellfish bed restoration and explore the implications of this project for shellfish bed restoration in the wider North Sea area

Shellfish bed restoration pilots Voordelta, Netherlands : Annual report 2018

The general objectives of the shellfish bed restoration pilots in the Voordelta are: to select suitable locations for shellfish bed restoration, identify critical factors for shellfish bed development, develop methods for shellfish bed restoration and explore the implications of this project for shellfish bed restoration in the wider North Sea area