41 research outputs found
Single hole transistor in a p-Si/SiGe quantum well
A single hole transistor is patterned in a p-Si/SiGe quantum well by applying
voltages to nanostructured top gate electrodes. Gating is achieved by oxidizing
the etched semiconductor surface and the mesa walls before evaporation of the
top gates. Pronounced Coulomb blockade effects are observed at small coupling
of the transistor island to source and drain.Comment: 3 pages, 3 figure
Advancing microbial sciences by individual-based modelling
Remarkable technological advances have revealed ever more properties and behaviours of individual microorganisms, but the novel data generated by these techniques have not yet been fully exploited. In this Opinion article, we explain how individual-based models (IBMs) can be constructed based on the findings of such techniques and how they help to explore competitive and cooperative microbial interactions. Furthermore, we describe how IBMs have provided insights into self-organized spatial patterns from biofilms to the oceans of the world, phage-CRISPR dynamics and other emergent phenomena. Finally, we discuss how combining individual-based observations with IBMs can advance our understanding at both the individual and population levels, leading to the new approach of microbial individual-based ecology (μIBE)
Solving the mystery of the FMC63-CD19 affinity
Abstract The majority of approved CAR T cell products are based on the FMC63-scFv directed against CD19. Surprisingly, although antigen binding affinity is a major determinant for CAR function, the affinity of the benchmark FMC63-scFv has not been unambiguously determined. That is, a wide range of affinities have been reported in literature, differing by more than 100-fold. Using a range of techniques, we demonstrate that suboptimal experimental designs can cause artefacts that lead to over- or underestimation of the affinity. To minimize these artefacts, we performed SPR with strictly monomeric and correctly folded soluble CD19, yielding an FMC63-scFv affinity of 2–6 nM. Together, apart from analyzing the FMC63-scFv affinity under optimized conditions, we also provide potential explanations for the wide range of published affinities. We expect that this study will be highly valuable for interpretations of CAR affinity-function relationships, as well as for the design of future CAR T cell generations
Energy alcohols : production and application of a synthetic liquid energy carrier
for use both on the transport sector and in the production of heat for domestic and industrial purposes will even in future be indispensable for those areas where pipe-line energy supply is impossible or uneconomical. are gainingincreasing importance. That applies to their application in situ for improving both the security of supply and the quality of conventional liquid fuels as well as to the transportation of energy in a system which is as economical as possible. are synthetic liquid secondary energy carriers. The examination of their potential with regard to profitable production and ecologically beneficial behaviour is the aim of the research programme outlined below. On the basis of the well-known process of , the programme highlights research objects which aim at improving the profitability andefficiency factor of the alcohol production. As regards the , two tendencies begin to show which differ as to the catalyst used and the respective process conditions. The optimization of the synthesis process concerns both the composition of the liquid product and the composition of the synthesis gas available. of differing quality can be produced on the basis of any carbonaceous raw material. All gas compositions can be simulated by means of a modified natural gas reforming plant (). The examination of the environmental behaviour of energy alcohols includes engine bench tests as well as experiments with different domestic burners. In this context, our main interest is focused on reaching a (particles, NO , hydrocarbons), on finding the optimum composition of energy alcohols, and on developing technical instructions as to transportation, storage, and application. The process calculations aim at determining the and at retaining and, if possible, utilizing the residues. The results of these calculations will provide the parameters for the
Infantile hypophosphatasia due to a new compound heterozygous TNSALP mutation - functional evidence for a hydrophobic side-chain?
BACKGROUND: Infantile hypophosphatasia (IH) is an inherited disorder characterized by defective bone mineralization and a deficiency of alkaline phosphatase activity. OBJECTIVE/DESIGN: The aim of the study was to evaluate a new compound heterozygous TNSALP mutation for its residual enzyme activity and localization of the comprised amino acid residues in a 3D-modeling. PATIENT: We report on a 4-week old girl with craniotabes, severe defects of ossification, and failure to thrive. Typical clinical features as low serum alkaline phosphatase, high serum calcium concentration, increased urinary calcium excretion, and nephrocalcinosis were observed. Vitamin D was withdrawn and the patient was started on calcitonin and hydrochlorothiazide. Nonetheless, the girl died at the age of 5 months from respiratory failure. RESULTS: Sequence analysis of the patient's TNSALP gene revealed two heterozygous mutations [c.653T>C (I201T), c.1171C>T (R374C)]. Transfection studies of the unique I201T variant in COS-7 cells yielded a mutant TNSALP protein with only a residual enzyme activity (3.7%) compared with wild-type, whereas the R374C variant was previously shown to reduce normal activity to 10.3%. 3D-modeling of the mutated enzyme showed that I201T resides in a region that does not belong to any known functional site. CONCLUSION: We note that I201, which has been conserved during evolution, is buried in a hydrophobic pocket and, therefore, the I>T-change should affect its functional properties. Residue R374C is located in the interface between monomers and it has been previously suggested that this mutation affects dimerization. These findings explain the patient's clinical picture and severe course