De long in een vijandige wereld

Afscheidscollege, Erasmus Univesiteit Rotterdam, op 11 oktober 1978. Geen organisme kan als biologische eenheid optimaal functioneren, tenzij alle verrichtingen, die nodig zijn voor zijn groei en voor zijn onderhoud, in de vereiste kwaliteit en kwantiteit kurmen plaatsvinden in een volkomen harmonieuze wisselwerking. Of deze verrichtingen nu plaatsvinden in het micromilieu van de eencellige' organismen, dan wel in het macromilieu van hoger gedifferentieerd'e' levensvormen, waarbij in toenemende mate bepaalde functies aan bepaalde organen of orgaansystemen in een vaak vergaande differentiatie worden gedelegeerd, in alle gevallen is een optimaal functioneren van het organisme als geheel alleen mogelijk, als een harmonieuae wisselwerking gewaarborgd is

Fluctuating "order parameter" for a quantum chaotic system with partially broken time-reversal symmetry

The functional defined as the squared modulus of the spatial average of the wave function squared, plays the role of an ``order parameter'' for the transition between Hamiltonian ensembles with orthogonal and unitary symmetry. Upon breaking time-reversal symmetry, the order parameter crosses over from one to zero. We compute its distribution in the crossover regime and find that it has large fluctuations around the ensemble average. These fluctuations imply long-range spatial correlations in the eigenfunction and non-Gaussian perturbations of eigenvalues, in precise agreement with results by Fal'ko and Efetov and by Taniguchi, Hashimoto, Simons, and Altshuler. As a third implication of the order-parameter fluctuations we find correlations in the response of an eigenvalue to independent perturbations of the system.Comment: 4 pages, REVTeX-3.0, 1 figure. Reference added to Y. V. Fyodorov and A. D. Mirlin, Phys. Rev. B 51, 13403 (1995

Thermopower of Single-Channel Disordered and Chaotic Conductors

We show (analytically and by numerical simulation) that the zero-temperature limit of the distribution of the thermopower S of a one-dimensional disordered wire in the localized regime is a Lorentzian, with a disorder-independent width of 4 pi^3 k_B^2 T/3e\Delta (where T is the temperature and \Delta the mean level spacing). Upon raising the temperature the distribution crosses over to an exponential form exp(-2|S|eT/\Delta). We also consider the case of a chaotic quantum dot with two single-channel ballistic point contacts. The distribution of S then has a cusp at S=0 and a tail |S|^{-1-\beta} log|S| for large S (with \beta=1,2 depending on the presence or absence of time-reversal symmetry).Comment: To be published in Superlattices and Microstructures, special issue on the occasion of Rolf Landauer's 70th birthda

β-Cell failure in type 2 diabetes: a case of asking too much of too few?

The islet in type 2 diabetes (T2DM) is characterized by a deficit in β-cells, increased β-cell apoptosis, and extracellular amyloid deposits derived from islet amyloid polypeptide (IAPP). In the absence of longitudinal studies, it is unknown if the low β-cell mass in T2DM precedes diabetes onset (is a risk factor for diabetes) or develops as a consequence of the disease process. Although insulin resistance is a risk factor for T2DM, most individuals who are insulin resistant do not develop diabetes. By inference, an increased β-cell workload results in T2DM in some but not all individuals. We propose that the extent of the β-cell mass that develops during childhood may underlie subsequent successful or failed adaptation to insulin resistance in later life. We propose that a low innate β-cell mass in the face of subsequent insulin resistance may expose β-cells to a burden of insulin and IAPP biosynthetic demand that exceeds the cellular capacity for protein folding and trafficking. If this threshold is crossed, intracellular toxic IAPP membrane permeant oligomers (cylindrins) may form, compromising β-cell function and inducing β-cell apoptosis

Reading Martha Lamont's Crow story today

It has often been noted that translation is interpretation. My presentation of the printed text of this story seeks to emphasize the parallel truth that decisions made concerning native-language transcription are also interpretive. Thus, the Lushootseed text is formatted in a style different from that of the English. In the Lushootseed text, a new line begins where a pause in the taped performance is preceded by falling intonation; double spaces mark pauses of more than two seconds or the occurrence of a pause accompanied by a change of delivery style (for instance, from straightforward style to declamatory, chanting, or otherwise marked style). Italics identify words and phrases spoken in characterized voices (for Crow or the seagulls), in chant form (characteristic of content that implies spiritual valence), or in a form that emphasizes the innate rhythms and internal echoes of the phrases being spoken (characteristic of formulaic portions of the story). My purpose was not to distinguish among these forms of speech, but merely to indicate the amount of specialized speech in Mrs. Lamont's storytelling.Issue title; "Native American Oral Traditions: Collaboration and Interpretation.

Performance Effects of the Corporatisation of Port of Rotterdam Authority

Port of Rotterdam Authority is a publicly owned but corporatized port development company. In 2004, this organisation was transformed from a municipal department to an independently operating company. The corporatisation intended to improve the overall performance of the port of Rotterdam. Relevant performance indicators to evaluate the effect of this corporatisation include market share, turnover, operating costs, profits, and investments. These indicators are evaluated for two periods, one prior to the corporatisation (1997-2003) and the other afterwards (2005-2011). The comparison of these two periods shows that corporatisation has led to significant performance improvements. This finding is relevant for the ongoing discussion on port governance models

Distribution of parametric conductance derivatives of a quantum dot

The conductance G of a quantum dot with single-mode ballistic point contacts depends sensitively on external parameters X, such as gate voltage and magnetic field. We calculate the joint distribution of G and dG/dX by relating it to the distribution of the Wigner-Smith time-delay matrix of a chaotic system. The distribution of dG/dX has a singularity at zero and algebraic tails. While G and dG/dX are correlated, the ratio of dG/dX and $\sqrt{G(1-G)}$ is independent of G. Coulomb interactions change the distribution of dG/dX, by inducing a transition from the grand-canonical to the canonical ensemble. All these predictions can be tested in semiconductor microstructures or microwave cavities.Comment: 4 pages, RevTeX, 3 figure

Hypoxia and muscle maintenance regulation: implications for chronic respiratory disease

PURPOSE OF REVIEW: Muscle wasting and impaired muscle oxidative metabolism are common extrapulmonary features of chronic respiratory failure (CRF) that significantly increase disease burden. This review aims to address the question whether hypoxia, an obvious consequence of this disease, actually plays a causal role in these muscle impairments. RECENT FINDINGS: In experimental models, a causal role for hypoxia in muscle atrophy and metabolic impairments has clearly been shown. Although the hypoxia-inducible factors and nuclear factor kappa B are putative mediators of these hypoxia-induced alterations, their true involvement remains to be proven. Molecular signatures of disrupted regulation of muscle mass and oxidative metabolism observed in these experimental models also have been shown in muscles of patients suffering from CRF, suggestive of but not conclusive for a causal role of hypoxia. Therapies, including but not restricted to those aimed at alleviating hypoxia, have been shown to partially but not completely restore muscle mass and oxidative capacity in CRF patients, which may imply an additive effect of nutritional modulation of substrate metabolism. SUMMARY: Although hypoxia clearly affects skeletal muscle maintenance, it remains to be confirmed whether and by which underlying molecular mechanisms hypoxia is causally involved in CRF-related muscle atrophy and impaired oxidative capacity

Создание условий для адаптации выпускников на рынке труда

There are errors in Table 1. Standard deviation is reported instead of standard error of the mean (SEM) for post-challenge stress protocol. Erroneous mean and SEM values are present for group-housed females in the GnRH challenge. Please see the corrected Table 1 here