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Abstract: Self-assembled InAs/(In,Ga)As quantum dots were embedded into n- or p-type Schottky diodes to investigate the conduction and valence band states, respectively. The samples were prepared by molecular beam epitaxy, and capacitance–voltage (C(V)) spectroscopy as well as photoluminescence (PL) measurements were performed and compared here. To study the influence of the capping layer, the quantum dots were overgrown either by GaAs or In0.15Ga0.85As. For the In0.15Ga0.85As cap, the ground state PL at 300K is red-shifted to 1319nm as compared to 1261nm for the GaAs cap. This red-shift observed in PL is compared to the shift of the corresponding electron and hole energy levels obtained from C(V) spectroscopy. It is found that only 18% of the red-shift originate from the valence band states, while 82% originate from the conduction band states. [Copyright &y& Elsevier]

Nanoscale devices are fabricated from modulation-doped GaAs/AlGaAs heterostructures, where the two-dimensional electron system is initially depleted. Upon removing the p-type capping layer that compensates for the n-type supply layer, the electron system is induced. Arbitrarily shaped areal, line, and dot elements, i.e. the nanostructures and 2D leads, are simultaneously fabricated by patterning a thin resist layer with an atomic force microscope and subsequent selective wet etching. In this way a single-electron transistor (SET) with a 60 nm diameter island, a 60 nm wide electron waveguide (EWG), and an Aharonov–Bohm (AB) loop of 110 nm average diameter are prepared. Measurements at T=1.5 K reveal Coulomb-blockade, quantized conductance and AB-oscillations for the SET, EWG, and AB loop, respectively. Finally, an EWG is demonstrated in split-gate geometry where the compensating layer is used as split gate. [Copyright &y& Elsevier]

Nanoscale devices are fabricated from modulation-doped GaAs/AlGaAs heterostructures, where the two-dimensional electron system is initially depleted. Upon removing the p-type capping layer that compensates for the n-type supply layer, the electron system is induced. Aharonov–Bohm (AB) loops of 110 and 160 nm diameter (average) and 35 nm width and conducting areas as leads are formed by patterning a thin resistant layer with an atomic force microscope and subsequent selective wet etching. At T=4.2 K and under perpendicular magnetic field the differential conductance of the AB loops exhibits an oscillatory pattern imposed on a smoothly varying background. The AB oscillation period of 480 mT (220 mT) corresponds well to the geometric dimension of the small (large) ring. [Copyright &y& Elsevier]

A randomised, open label phase III trial was conducted to evaluate efficacy of nimotuzumab, a monoclonal antibody against epidermal growth factor receptor (EGF-R) added to standard therapy for newly diagnosed glioblastoma. 149 glioblastoma patients stratified as with or without residual tumour were randomly assigned to receive either intravenous nimotuzumab 400 mg weekly added to standard radiochemotherapy followed by 400 mg biweekly after twelve weeks or standard radiochemotherapy. Progression status after 52 weeks (12moPFS) and progression-free survival (PFS) based on Macdonald criteria were co-primary and overall survival (OS), toxicity and quality of life secondary end-points. 142 patients were evaluated for efficacy (per protocol cohort). 12moPFS was 25.6% in the experimental arm and 20.3% in the control group. In residual tumour patients (n = 81) median PFS was 5.6 versus 4.0 months, (hazard ratio (HR), 0.87; 95% confidence interval (CI), 0.55–1.37), for patients without residual tumour (n = 61) it was 10.6 versus 9.9 months, (HR, 1.01; 95% CI, 0.57–1.77). Median OS in patients with residual tumour was 19.5 versus 16.7 months, (HR, 0.90; 95% CI, 0.52–1.57; P = 0.7061), for patients without 23.3 versus 21.0 months (HR, 0.77; 95% CI, 0.41–1.44; P = 0.4068). A small cohort of MGMT non-methylated patients with residual tumour showed PFS of 6.2 versus 4.0 months (HR, 0.77; 95% CI, 0.35–1.67; P = 0.4997) and OS of 19.0 versus 13.8 months (HR, 0.66; 95% CI, 0.27–1.64; P = 0.3648). EGF-R amplification did not correlate with clinical efficacy of nimotuzumab. Nimotuzumab was well tolerated. This study, albeit negative, contains hypothesis generating signals supporting evaluation of correlative, efficacy-predicting tumour parameters for nimotuzumab in the treatment of glioblastoma. [ABSTRACT FROM AUTHOR]

Abstract: Certain organisms found across a range of taxa, including bacteria, yeasts, plants and many invertebrates such as nematodes and tardigrades are able to survive almost complete loss of body water. The dry organisms may remain in this state, which is known as anhydrobiosis, for decades without apparent damage. When water again becomes available, they rapidly rehydrate and resume active life. Research in anhydrobiosis has focused mainly on sugar metabolism and stress proteins. Despite the discovery of various molecules which are involved in desiccation and water stress, knowledge of the regulatory network governing the stability of the cellular architecture and the metabolic machinery during dehydration is still fragmentary and not well understood. A combination of transcriptional, proteomic and metabolic approaches with bioinformatics tools can provide a better understanding of gene regulation that underlie the biological functions and physiology related to anhydrobiosis. The development of this concept will raise exciting possibilities and techniques for the preservation and stabilization of biological materials in the dry state. [Copyright &y& Elsevier]