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Contextual perspectives on education in materials science and engineering

From an inside point of view, the concept of a "unified science of materials" might appear to be quite natural in its own right, as it were. However, considering the fact that science in general is practiced by humans in a social environment, it should be warranted to examine materials science also from the humanistic and sociological perspectives, as well as against the background of current thin

Common structure in amorphised compound semiconductors

Extended X-ray absorption fine structure has been utilised to determine the structural parameters of the amorphous III-V semiconductors GaP, GaAs, InP and InAs. The amorphous phase was formed by ion implantation to inhibit preparation-specific artefacts associated with the alternative fabrication techniques of sputtering and evaporation. Relative to crystalline standards, increases in bond length

Solid Phase Micro Extraction Fibers, Calibration for Use in Biofilter Applications

The main purpose of this study is to develop a SPME calibration method suitable for use in evaluation of concentrations of hydrophobic substances in environmental samples. The analyte used in the experiments was alpha-pinene, a hydrophobic organic compound commonly found in wood, and therefore found in wood storage facilities, wood processing industries and wood based biofilters. The SPME fibres w

A computer-oriented method for reducing linearized multibody equations by incorporating constraints

Consider a spatial multibody system with rigid and elastic bodies. The bodies are linked by rigid interconnections (e.g. revolute joints) causing constraints, as well as by flexible interconnections (e.g. springs) causing applied forces. Small motions of the system with respect to a given nominal configuration can be described by linearized dynamic equations and kinematic constraint equations. We

Crystal structure of Plasmodium falciparum spermidine synthase in complex with the substrate decarboxylated S-adenosylmethionine and the potent inhibitors 4MCHA and AdoDATO

Plasmodium falciparum is the causative agent of the most severe type of malaria, a life-threatening disease affecting the lives of over three billion people. Factors like widespread resistance against available drugs and absence of an effective vaccine are seriously compounding control of the malaria parasite. Thus, there is an urgent need for the identification and validation of new drug targets.

Individual variation and repeatability of sex pheromone emission of female turnip moths Agrotis segetum

Individual variation of the female sex pheromone signal in Agrotis segetum was determined by gas chromatographic analysis. The individuals varied extensively, both in absolute and relative amounts of the three major pheromone components; Z5-10:OAc, Z7-12:OAc and Z9-14:OAc. Within individuals there was a strong correspondence between the sex pheromone gland content and the signal actually emitted.

Interpretation of EXAFS spectra for sitting-atop complexes with the help of computational methods

The metallation of tetrapyrroles is believed to proceed via a sitting-atop (SAT) complex, in which some of the pyrrole nitrogen atoms are protonated and the metal ion resides above the ring plane. No crystal structure of such a complex has been presented, but NMR and EXAFS (extended X-ray absorption fine structure) data has been reported for Cu2+ in acetonitrile, which have been interpreted as the

Soil carbon sequestration in traditional farming in Sudanese dry lands

Do altered land management practices offer possibilities to sequester carbon in the soil and thereby mitigate increasing atmospheric CO2 as well as improve local soil fertility? This study investigates the impact of fallow periods on soil organic carbon in semiarid subsistence agroecosystems on sandy and poor soils in Kordofan, Sudan. The area is characterized by low-input cultivation of millet an

Environmental effects on flying migrants revealed by radar

Migratory animals are affected by various factors during their journeys, and the study of animal movement by radars has been instrumental in revealing key influences of the environment on flying migrants. Radars enable the simultaneous tracking of many individuals of almost all sizes within the radar range during day and night, and under low visibility conditions. We review how atmospheric conditi

Innovation Policies and New Regional Growth Paths : A Place-Based System Failure Framework

Fundamental and enduring changes brought about by recurrent economic and financial crises, the digital revolution and ongoing globalisation processes of production and innovation activities are posing major challenges for regional and national economies to renew their industrial structures and develop innovations that break existing development trajectories. This calls for new innovation policy ap

Dignity and displaced Syrians in Lebanon. ‘There is no karama here’

Since the popular uprising and subsequent war in Syria in 2011, more than a quarter of its population have fled – mainly to Turkey, Lebanon, Jordan, Iraq and Egypt – and another 25% have been internally displaced. The end of 2017 saw 12.6 million Syrians forcibly displaced – 6.3 million refugees, 6.2 million internally displaced (IDPs) and 146,700 asylum-seekers. In the words of the United Nations

Protecting the dignity of displaced Syrians

What does dignity mean to Syrian refugees and practitioners? And what can humanitarian organisations do – or abstain from doing – to help Syrians preserve and protect their dignity?