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Broadband attosecond pulse shaping

We use semiconductor (Si) and metallic (Al, Zr) transmission filters to shape, in amplitude and phase, high-order harmonics generated from the interaction of an intense titanium sapphire laser field with a pulsed neon gas target. Depending on the properties of the filter, the emitted attosecond pulses can be optimized in bandwidth and/or pulse length. We demonstrate the generation of attosecond pu

Evolution of photosensory pineal organs in new light: the fate of neurodocrine photoreceptors

Pineal evolution is envisaged as a gradual transformation of pinealocytes (a gradual regression of pinealocyte sensory capacity within a particular cell line), the so-called sensory cell line of the pineal organ. In most non-mammals the pineal organ is a directly photosensory organ, while the pineal organ of mammals (epiphysis cerebri) is a non-sensory neuroendocrine organ under photoperiod contro

Kinetic study of the selective reduction of nitric oxide over vanadia—tungsta—titania/sepiolite catalyst

A kinetic study of the reduction of nitric oxide by ammonia in the presence of oxygen on a novel catalyst prepared as a physical mixture of V2O5-WO3/TiO2 catalyst and a natural silicate (sepiolite) was carried out. The steady-state differential reactor data were fitted to several equations using a discriminating method based on physical and statistic criteria. The best fit was obtained from a mode

Consumption patterns and excretion in aquatic food websenrichment,

This thesis links biogeochemical cycling to classical ecology. Predictions derived from food chain theory, based on Lotka-Volterra type of interactions, were tested in aquatic environments with the main hypothesis that consumers affect lower levels of organization by both predation and excretion of limiting nutrients. From tank experiments it was concluded that predation may affect prey populatio

Rewriting in operads and PROPs

This paper is an informal collection of observations on how established rewriting techniques can be applied to or need to be adapted for use in non-associative algebras, operads, and PROPs.

Subtle sequence differences in a turnour-associated peptide epitope translate into major changes in antigenicity

Antigenicity, the ability to bind to members of repertoire of diverse immune receptors, is a concept that is poorly characterised with respect to its defining parameters. To learn more about its makeup, we have investigated the ability of two peptides with highly related sequences, derived from the tumour-associated antigen mucin-1, to recruit in vitro members from a large naive repertoire of synt

Extreme value theory for queues via cycle maxima

The present state of extreme value theory for queues is surveyed. The exposition focuses on the regenerative properties of queueing systems, which reduces the problem to the study of the tail of the maximum $overline X( au)$ of the queueing process ${X(t)}$ during a regenerative cycle $ au$. For simple queues, methods for obtaining the distribution of $overline X( au)$ both explicitly and asymptot

A theoretical study of the copper–cysteine bond in blue copper proteins

The accuracy of theoretical calculations on models of the blue copper proteins is investigated using density functional theory (DFT) Becke's three-parameter hybrid method with the Lee–Yang–Parr correlation functional (B3LYP) and medium-sized basis sets. Increasing the basis set to triple-zeta quality with f-type functions on all heavy atoms and enlarging the model [up to Cu(imidazole-CH3)2(SC2H5)

Concord and Conflict: the Hui Communities of Yunnan Society in a Historical Perspective

This dissertation studies the historical relation between the Muslim minority and the non-Muslim majority in Yunnan with a combined method: historical criticism supplemented by ethnological interpretation. This relation manifests in history dynamic and dialectical characteristics: concord and conflict. Concord can be found in the stable and balanced periods in the relevant socio-cultural aspects o

Extracellular nucleotides ATP and UTP induce a marked acute release of tissue-type plasminogen activator in vivo in man

Extracellular nucleotides such as ATP and UTP are released by activation of platelets and ischemic tissue injury. The aim of the present study was to investigate whether ATP and UTP can induce acute tPA release from the vascular endothelium in vivo. Nine healthy subjects were studied in a perfused-forearm model during stepwise intraarterial infusions of ATP and UTP (10-200 nmol/min), and UTP durin

Radiative lifetime measurements and oscillator strength determination for transitions in singly ionized praseodymium (Pr II)

New radiative lifetimes for 20 levels of Pr II have been measured using the time-resolved laser-induced fluorescence (LIF) technique. The combination of these experimental values with theoretical branching fractions (BF) obtained with the pseudo-relativistic Hartree-Fock (HFR) approach has allowed us to determine oscillator strengths and transition probabilities for about 150 lines appearing in th