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Interference of Independently Emitted Electrons in Quantum Shot Noise

heory predicts that electrons emitted from independent electron sources (metallic contacts) can nevertheless interfere. This interference is manifest in an exchange contribution to the shot noise correlation of currents at different contacts of a mesoscopic conductor. A geometry has been proposed in which second order (single particle) interference due to superposition of amplitudes is absent but

Immediate administration of tranexamic acid and reduced incidence of early rebleeding after aneurysmal subarachnoid hemorrhage: a prospective randomized study.

OBJECT: By pursuing a policy of very early aneurysm treatment in neurosurgical centers, in-hospital rebleeds can be virtually eliminated. Nonetheless, as many as 15% of patients with aneurysm rupture suffer ultraearly rebleeding with high mortality rates, and these individuals are beyond the reach of even the most ambitious protocol for diagnosis and referral. Only drugs given immediately after th

Low-temperature spectroscopy of fully active cores. Comparison with CP43, CP47,

Comparisons of absorption spectra of photosystem II (PSII) core complexes with those of isolated CP43, CP47 and D1/D2/cyt b559 complexes show broadenings and shifts upon disassembly of the PSII core material. Spectra of PSII cores isolated from plants and cyanobacteria reveal marked changes in energies and intensities of the sharp features associated with P680. Low-temperature, illumination-induce

Metal chelate affinity precipitation of RNA and purification of plasmid DNA

The affinity of metal chelates for amino acids, such as histidine, is widely used in purifying proteins, most notably through six-histidine `tails'. We have found that metal affinity interactions can also be applied to separation of single-stranded nucleic acids through interactions involving exposed purines. Here we describe a metal affinity precipitation method to resolve RNA from linear and pla

The foldable "Ottenby" walk-in trap: a handy and efficient wader trap for expedition conditions.

We describe the history, construction, and use of a portable walk-in wader trap (i.e., modified Ottenby trap) designed to be used in field expedition conditions. It is rectangular-shaped, 120 x 41 x 32 cm when operational, weighs between 1.5 and 2 kg (depending on materials used) and can be folded flat for easy transportation. It consists of several metal frames filled with fishing net, and has a

The effect of sympathetic stimulation on proximal brachial artery mechanics in humans - differential behaviour within the length of the brachial artery?

Aims: The mechanical properties of arteries play a major role in the regulation of blood pressure and cardiac performance. The effect of sympathetic stimulation on the mechanical properties of the proximal brachial artery was analysed in 18 healthy volunteers, nine young (25 +/- 2 years) and nine elderly (69 +/- 2 years). Methods: A non-invasive ultrasonic echo-tracking system for measurement of s

Geographic variation in the field response of male European pine sawflies, Neodiprion sertifer , to different pheromone stereoisomers and esters

The European pine sawfly, Neodiprion sertifer (Geoffroy) (Hymenoptera: Diprionidae), is a widespread and economically important forest insect. The sex pheromone communication system of this species has been previously investigated in North America, Japan and Europe, with the acetate or propionate of the alcohol (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) shown to be the main pheromone compo

Dendritic cell maturation results in pronounced changes in glycan expression affecting recognition by siglecs and galectins

Dendritic cells (DC) are the most potent APC in the organism. Immature dendritic cells (iDC) reside in the tissue where they capture pathogens whereas mature dendritic cells (mDC) are able to activate T cells in the lymph node. This dramatic functional change is mediated by an important genetic reprogramming. Glycosylation is the most common form of posttranslational modification of proteins and h

Changes in aneurysm morphology and stent-graft configuration after endovascular repair of aneurysms of the descending thoracic aorta

OBJECTIVE: We sought to study changes in morphology and stent-graft configuration of descending thoracic aortic aneurysms after endovascular repair. METHODS: Twenty-three patients treated with custom-made stent-grafts were studied. The stent-graft consisted of continuous, stainless-steel Z stents mounted within a polyester graft. In the last 11 cases the stents were interconnected with 3 longitudi

Comparative dosimetry of diode and diamond detectors in electron beams for intraoperative radiation therapy

The aim of the present study is to examine the validity of using silicon semiconductor detectors in degraded electron beams with a broad energy spectrum and a wide angular distribution. A comparison is made with diamond detector measurements, which is the dosimeter considered to give the best results provided that dose rate effects are corrected for. Two-dimensional relative absorbed dose distribu

Tropical forests and the global carbon cycle: impacts of atmospheric carbon dioxide, climate change and rate of deforestation

The remaining carbon stocks in wet tropical forests are currently at risk because of anthropogenic deforestation, but also because of the possibility of release driven by climate change. To identify the relative roles of CO2 increase, changing temperature and rainfall, and deforestation in the future, and the magnitude of their impact on atmospheric CO2 concentrations, we have applied a dynamic gl