How honey bees make fast and accurate decisions.

Honey bee ecology demands they make both rapid and accurate assessments of which flowers are most likely to offer them nectar or pollen. To understand the mechanisms of honey bee decision-making, we examined their speed and accuracy of both flower acceptance and rejection decisions. We used a controlled flight arena that varied both the likelihood of a stimulus offering reward and punishment and the quality of evidence for stimuli.

Acute renal failure in the ICU: risk factors and outcome evaluated by the SOFA score.

Objectives: To describe risk factors for the development of acute renal failure (ARF) in a population of intensive care unit (ICU) patients, and the association of ARF with multiple organ failure (MOF) and outcome using the sequential organ failure assessment (SOFA) score.

Design: Prospective, multicenter, observational cohort analysis.

Setting: Forty ICUs in 16 countries.

Mechanisms and prevention of secondary brain damage during intensive care.

The injured brain may be damaged by primary impact, secondary injury from secondary damage due to initiation of destructive inflammatory and biochemical cascades by the primary injury or secondary ischemic injury following secondary insults that initiate or augment these immunological and biochemical cascades. Cerebral ischemia will arise whenever delivery of oxygen and substrates to the brain fall below metabolic needs. Many factors lead to the development of secondary insults to the injured brain during initial resuscitation, transport, surgery, and subsequent intensive care.

Cerebral haemodynamics and embolization during carotid angioplasty in high-risk patients.

Background: Patients with symptomatic internal carotid artery (ICA) stenosis greater than 70 per cent in association with a contralateral ICA occlusion may have an increased risk of stroke following carotid endarterectomy. Such patients might benefit from the theoretically shorter ischaemic time offered by carotid angioplasty and stenting.

Methods: Nine patients who underwent carotid angioplasty and stenting were monitored using near-infrared spectroscopy, continuous jugular venous oximetry and transcranial Doppler ultrasonography to detect both haemodynamic ischaemia and embolic events.