Stop het graven! in 2024 liggen alle kabels en leidingen in goten

In de Nederlandse bodem ligt ongeveer twee miljoen kilometer aan kabels en leidingen. Het grootste deel hiervan ligt in binnenstedelijk gebied, waar de druk op gebruik van publieke ruimte het grootst is. Een spaghetti van gebruikte en ongebruikte kabels, leidingen en buizen maken het niet alleen ingewikkeld om onderhoud te verrichten, maar kunnen ook leiden tot graafschades en uitloop van civieltechnische werken. In dit artikel vragen we ons af hoe lang nutsinfrastructuur nog op deze manier wordt aangelegd. We bespreken hoe kabels en leidinggoten uitkomst zouden kunnen bieden bij het ordenen van ondergrondse netten. Ook inventariseren we enkele aandachtspunten voor deze procesinnovatie en dragen suggesties aan voor het implementeren hiervan

EMVI en snellere binnenstedelijke rioleringsprojecten:wat te doen met nutscoordinatie?

Sinds invoering van de nieuwe aanbestedingswet hanteren gemeenten en provincies een ‘EMVI, tenzij-beleid’: in plaats van beoordeling op basis van (louter) laagste prijs, worden werken gegund aan de aanbieder met de ‘economisch meest voordelige inschrijving’. Door deze aanpak kan de opdrachtgever bij het selecteren van een aanbieder ook focussen op waarde en efficiëntie van het bouwproces. Met criteria als risicobeheersing en bereikbaarheid kunnen opdrachtgevers bijvoorbeeld sturen op minimalisatie van de doorlooptijd of voorkoming van hinder. Of toch niet? In dit artikel lichten we toe waarom dit bij projecten die raakvlakken hebben met nutsinfra complexer ligt, vanwege ingewikkelde coördinatie van nutswerkzaamheden door civiele aannemers. Om beoogde effecten van procescriteria in de toekomst te behalen, pleiten we daarom voor een grotere rol van het aspect nutscoördinatie bij EMVI-aanbestedingen van civiele werken. We betogen ten slotte dat civiele werken met een ‘black box’ aan kabels en leidingen zich niet goed lenen voor EMVI-aanbestedingen. Hier is mogelijk een alternatief met elementen van Best Value Procurement (BVP) meer geschikt

Review and analysis of small-scale aquaculture production in East Africa : Summary and Recommendations

This report describes the findings of literature studies and of interviews with fish farmers and key informants in Kenya, Rwanda, Tanzania and Uganda as well as recommended actions that result from the findings. The studies were commissioned by Msingi East Africa in collaboration with Stichting BoP Innovation Centre and have been reported in four separate reports, covering each country. This final report provides a summary of all country reports. Extensive to semi-intensive production of Tilapia and to a lesser extent, African Catfish in small ponds is the most common production system in the region. However, there is a rapidly expanding culture of tilapia production in floating cages taking place in Lake Victoria and in other lakes. The situation of small-scale aquaculture producers as well as support services in the four countries differs but most small-scale fish farmers in the region are confronted with a shortage of essential inputs (especially fish feed, fingerlings and credit) of good quality and affordable price. The level of knowledge about better farm management practices, of related skills and application of more advanced technology (needed to increase productivity and income) is low for most farmers. For most countries the opportunities for the more advanced segment of small-scale farmers to grow are good. The study recommends a number of actions which it is believed will contribute to growth of smallholders’ production and income for all the countries surveye

Determining Peptide Partitioning Properties via Computer Simulation

The transfer of polypeptide segments into lipid bilayers to form transmembrane helices represents the crucial first step in cellular membrane protein folding and assembly. This process is driven by complex and poorly understood atomic interactions of peptides with the lipid bilayer environment. The lack of suitable experimental techniques that can resolve these processes both at atomic resolution and nanosecond timescales has spurred the development of computational techniques. In this review, we summarize the significant progress achieved in the last few years in elucidating the partitioning of peptides into lipid bilayer membranes using atomic detail molecular dynamics simulations. Indeed, partitioning simulations can now provide a wealth of structural and dynamic information. Furthermore, we show that peptide-induced bilayer distortions, insertion pathways, transfer free energies, and kinetic insertion barriers are now accurate enough to complement experiments. Further advances in simulation methods and force field parameter accuracy promise to turn molecular dynamics simulations into a powerful tool for investigating a wide range of membrane active peptide phenomena

A Sensory Valve in Liposomal Drug Delivery Systems

A mechano-gated membrane channel protein is used as a controllable, nonselective, large, aqueous pore in sterically stabilized liposomal drug delivery systems. The channel protein is engineered first to sense the light and/or the pH under iso-osmotic conditions, and then to convert these signals into conformational changes ultimately leading to pore formation in the drug loaded liposomes. This system offers not only the target specific drug delivery but also control over the timing of the delivery.

Mini-hemagglutinin vaccination induces cross-reactive antibodies in pre-exposed NHP that protect mice against lethal influenza challenge

Seasonal vaccines are currently the most effective countermeasure against influenza. However, seasonal vaccines are only effective against strains closely related to the influenza strains contained in the vaccine. Recently a new hemagglutinin (HA) stem-based antigen, the so-called "mini-HA", has been shown to induce a cross-protective immune response in influenza-naive mice and non-human primates (NHP). However, prior exposure to influenza can have a profound effect on the immune response to subsequent influenza infection and the protective efficacy of vaccination. Here we show that mini-HA, compared to a trivalent influenza vaccine (TIV), elicits a broadened influenza-specific humoral immune response in NHP previously exposed to influenza. Serum transfer experiments showed that antibodies induced by both mini-HA and seasonal vaccine protected mice against lethal challenge with a H1N1 influenza strain heterologous to the H1 HA included in the TIV. However, antibodies elicited by mini-HA showed an additional benefit of protecting mice against lethal heterosubtypic H5N1 influenza challenge, associated with H5 HA-specific functional antibodies