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Recalcitrant carbon components in glomalin-related soil protein facilitate soil organic carbon preservation in tropical forests

Glomalin-related soil protein (GRSP) is known as an important microbial by-product which is crucial for preserving or accumulating soil organic carbon (SOC). However, the underlying mechanisms are not well understood. In this study, we investigated the chemical structures of GRSP and its relationship with SOC using 13C nuclear magnetic resonance (NMR) in three tropical forests. The three forests,

Agility in entrepreneurial projects

Managing entrepreneurship is of importance for the society, for organizations and for the individual. It is not enough with knowledge and skills relating to the idea behind entrepreneurship. The entrepreneur must have knowledge and skills to manage the entrepreneurial process. The purpose of this paper is to put forward for agile project management as an appropriate way to manage an entrepreneuria

Managing Project complexity - a managerial view

In this paper we are investigating how project complexity is affecting the management of single projects in a multi-project environment. The project manager’s perspective is applied. A conceptual framework is developed in order to summarize how project complexity effect project management. The framework is applied to two cases and conclusions are drawn.

Single amino acid substitutions in the selectivity filter render NbXIP1;1α aquaporin water permeable

BACKGROUND: Aquaporins (AQPs) are integral membrane proteins that facilitate transport of water and/or other small neutral solutes across membranes in all forms of life. The X Intrinsic Proteins (XIPs) are the most recently recognized and the least characterized aquaporin subfamily in higher plants. XIP1s have been shown to be impermeable to water but permeable to boric acid, glycerol, hydrogen pe

The specific costing problems of project form

Project costing is an area where more research is needed. Beginning from typical project characteristics discusses the specific costing problems of the project. The focus is on how those problems can be managed using activity-based costing. The article also takes up a short discussion about the critical moments of the project costing.

Four dimensional material movies : High speed phase-contrast tomography by backprojection along dynamically curved paths

We present an approach towards four dimensional (4d) movies of materials, showing dynamic processes within the entire 3d structure. The method is based on tomographic reconstruction on dynamically curved paths using a motion model estimated by optical flow techniques, considerably reducing the typical motion artefacts of dynamic tomography. At the same time we exploit x-ray phase contrast based on

Location, location &size : Defects close to surfaces dominate fatigue crack initiation

Metallic cast components inevitably contain defects such as shrinkage cavities which are inherent to the solidification process. Those defects are known to significantly alter the fatigue life of components. Yet very little is known, quantitatively, on the dangerosity of internal casting defects compared to surface ones. In this study, fatigue specimens containing controlled internal defects (shri

Drainage mechanisms in porous media : From piston-like invasion to formation of corner flow networks

Water drainage from porous media is a highly dynamic process often marked by rapid piston-like air invasion events at the front and other rapid interfacial reconfigurations. Liquid phase entrapped behind the moving front drains at significantly slower rates often via gravity driven flow through corners and crevices. This distribution of slowly draining residual water phase determines the plant ava

Fast Synchrotron X-Ray Tomography of Dynamic Processes in Liquid Aluminium Alloy Foam

Series of fast synchrotron X-ray tomographies are taken continuously at a rate of up to 5Hz, while aluminium alloy precursors are foamed in an X-ray transparent setup for several minutes using infra-red (IR) lasers for heating. The entire foaming process from the solid precursor to the expanded liquid foam is captured. The analysis of the sequence of tomographies is done with an emphasis on nuclea

Characterization and micromechanical modelling of microstructural heterogeneity effects on ductile fracture of 6xxx aluminium alloys

Ductile failure of three 6xxx serie aluminium alloys has been characterized and modelled for about thirty hardening conditions each. These alloys involve relatively similar composition and volume fraction of second phase particles. The tensile mechanical properties show the expected decrease of fracture strain with increasing strength but also major differences among the different alloys with a fa

Real-time material's response to high power microwave irradiation revealed by in-situ synchrotron radiation methods

The complexity of microwave heating stems to a large extent from the intrinsic complexity of the materials exposed to microwave irradiation. For simple ideal homogeneous material, its size, shape and orientation with respect to the electromagnetic field influence the microwave absorption properties at the macroscopic scale. Furthermore, a number of material parameters, namely the complex permittiv

Four-dimensional in vivo X-ray microscopy with projection-guided gating

Visualizing fast micrometer scale internal movements of small animals is a key challenge for functional anatomy, physiology and biomechanics. We combine phase contrast tomographic microscopy (down to 3.3 μm voxel size) with retrospective, projection-based gating (in the order of hundreds of microseconds) to improve the spatiotemporal resolution by an order of magnitude over previous studies. We de

Structural mouthpart interaction evolved already in the earliest lineages of insects

In butterflies, bees, flies and true bugs specific mouthparts are in close contact or even fused to enable piercing, sucking or sponging of particular food sources. The common phenomenon behind these mouthpart types is a com-plex composed of several consecutive mouthparts which structurally interact during food uptake. The single mouthparts are thus only functional in con-junction with other adjac

Simultaneous dual-energy X-ray stereo imaging

Dual-energy or K-edge imaging is used to enhance contrast between two or more materials in an object and is routinely realised by acquiring two separate X-ray images each at different X-ray wavelength. On a broadband synchrotron source an imaging system to acquire the two images simultaneously was realised. The single-shot approach allows dual-energy and stereo imaging to be applied to dynamic sys

Deformation behavior of sintered nanocrystalline silver layers

Abstract The microstructure of porous silver layers produced under different low temperature pressure-assisted sintering conditions is characterized and linked with the mechanical behavior studied insitu during X-ray diffraction. Peak profile analysis reveals important strain recovery and hardening mechanism during cyclic deformation. The competition between both mechanisms is discussed in terms o