Subsidence reveals potential impacts of future sea level rise on inhabited mangrove coasts

Human-induced land subsidence causes many coastal areas to sink centimetres per year, exacerbating relative sea level rise (RSLR). While cities combat this problem through investment in coastal infrastructure, rural areas are highly dependent on the persistence of protective coastal ecosystems, such as mangroves and marshes. To shed light on...

Chenier Dynamics

Over the last decades, mangrove forests have suffered immense and rapid losses worldwide. In recognition of their important socio-economic and environmental functions, many attempts have been made to both protect the remaining mangrove coastlines and restore eroding sites. Unfortunately, many rehabilitation attempts have failed, lacking a...

Chenier Formation Through Wave Winnowing and Tides

Cheniers are ridges consisting of coarse-grained sediments, resting on top of the fine sediment that forms the otherwise muddy coast. In this paper, we use Delft3D to explore how cheniers are formed through wave winnowing. We identify three phases of chenier development: (a) a winnowing phase, during which mud is washed out of the seabed...

Drivers of cross-shore chenier dynamics off a drowning coastal plain

A chenier is a beach ridge, consisting of sand and/or shells, overlying a muddy substrate. In this paper, we explore the cross-shore dynamics of cheniers in their ‘active’ phase, i.e. the phase between their formation and their landing on the shore and can no longer be reached by daily wave and tidal influences. While cheniers described in...

Block-matching-based registration to evaluate ultrasound visibility of percutaneous needles in liver-mimicking phantoms

Purpose: To present a novel methodical approach to compare visibility of percutaneous needles in ultrasound images. Methods: A motor-driven rotation platform was used to gradually change the needle angle while capturing image data. Data analysis was automated using block-matching-based registration, with a tracking and refinement step. Every...

Efficacy assessment of newly-designed filtering facemasks during the sars-cov-2 pandemic

The SARS-CoV-2 pandemic resulted in shortages of production and test capacity of FFP2-respirators. Such facemasks are required to be worn by healthcare professionals when performing aerosol-generating procedures on COVID-19 patients. In response to the high demand and short supply, we designed three models of facemasks that are suitable for...

Managing erosion of mangrove-mud coasts with permeable dams – lessons learned

Mangrove-mud coasts across the world erode because of uninformed management, conversion of mangrove forests into aquaculture ponds, development of infrastructure and urbanization, and/or extraction of groundwater inducing land subsidence. The accompanied loss of ecosystem values, amongst which safety against flooding, has far reaching...

Observations of cross-shore chenier dynamics in Demak, Indonesia

Cheniers are important for stabilising mud-dominated coastlines. A chenier is a body of wave-reworked, coarse-grained sediment consisting of sand and shells overlying a muddy substrate. In this paper we present and analyse a week of field observations of the dynamics of a single chenier along the coast of Demak, Indonesia. Despite relatively...

Guided by light: Optical control of microtubule gliding assays

Force generation by molecular motors drives biological processes such as asymmetric cell division and cell migration. Microtubule gliding assays in which surface-immobilized motor proteins drive microtubule propulsion are widely used to study basic motor properties as well as the collective behavior of active self-organized systems....

Needle placement errors: do we need steerable needles in interventional radiology?

Purpose: Accurate and precise needle placement is of utmost importance in interventional radiology. However, targeting can be challenging due to, eg, tissue motion and deformation. Steerable needles are a possible solution to overcome these challenges. The present work studied the clinical need for steerable needles. We aimed to answer three...

Wave transformation on the mangrove-mud coast of Demak, Indonesia

In this paper the typical hydrodynamics on mangrove-mud coasts are studied. Worldwide, these coasts experience serious erosion problems, and while the importance of mangrove ecosystems is becoming widely recognised, mangrove restoration projects frequently fail due to poor understanding of the system, especially the hydrodynamics. Therefore, a...

Wave attenuation by brushwood dams in a mud-mangrove coast

During recent decades, mangrove forests have experienced severe degradation due to unsustainable land use. Restoration of mangrove ecosystems requires the recovery of their habitat, considering ecology, hydrology, hydrodynamics, and sediment transport. In a first pilot in 2013, brushwood dams were built on the eroding coast of Demak, Indonesia,...