Snakes elicit specific neural responses in the human infant brain.

Detecting predators is essential for survival. Given that snakes are the first of primates' major predators, natural selection may have fostered efficient snake detection mechanisms to allow for optimal defensive behavior. Here, we provide electrophysiological evidence for a brain-anchored evolved predisposition to rapidly detect snakes in humans, which does not depend on previous exposure or knowledge about snakes. To do so, we recorded scalp electrical brain activity in 7- to 10-month-old infants watching sequences of flickering animal pictures. All animals were presented in their natural background. We showed that glancing at snakes generates specific neural responses in the infant brain, that are higher in amplitude than those generated by frogs or caterpillars, especially in the occipital region of the brain. The temporal dynamics of these neural responses support that infants devote increased attention to snakes than to non-snake stimuli. These results therefore demonstrate that a single fixation at snakes is sufficient to generate a prompt and large selective response in the infant brain. They argue for the existence in humans of an inborn, brain-anchored mechanism to swiftly detect snakes based on their characteristic visual features.

Microscopic characterisation of photodetectors used in the hadron calorimeter of the Compact Muon Solenoid experiment.

The Hybrid Photodetector (HPD) is a hybrid unit with a single accelerating gap between a common photocathode and an array of PIN diodes. Customised HPDs with 19 channels were used to detect scintillation light from hadron calorimeter in the Compact Muon Solenoid (CMS) experiment. In this paper, we present results on radiation damage studies carried out on the used HPDs in the outer hadron (HO) and the end-cap hadron (HE) calorimeter of the CMS experiment operating at CERN. The calorimeter is made of alternating layers of scintillating tiles and metals, such as brass or iron. The scintillating light was transmitted to the HPDs by means of optical fibres. Due to excessive exposure to scintillation light and ionising radiation during data taking at the Large Hadron Collider, the performance of the HPDs was expected to degrade significantly in the HE detector. Independent studies on radiation damage of these used photosensors were important to assess the degradation in the performance of the calorimeter. Microscopic scans of relative photon detection efficiencies for two HPDs (one each from HO and HE detector) were made using micron resolution optical scanner. The scanner was specially designed and built for microscopic characterisation of photosensors. Imprints of each fibre (∼1 mm in diameter) on the photocathode with varying damage within the same pixel of the HPD were observed. The localised damage of the photocathode was determined to vary with the amount of scintillation (or calibration) light transmitted by optical fibres to the HPD.

Comparison of the responsiveness of the Harris Hip Score with generic measures for hip function in osteoarthritis of the hip.

OBJECTIVE: To compare responsiveness of the Harris Hip Score with generic measures (that is, the Short Form-36 (SF-36), and a test of walking speed and pain during walking) in patients with osteoarthritis (OA) of the hip. METHOD: The first 75 cases within the population of a randomised clinical trial on manual therapy and exercise therapy were selected for secondary analysis. Experienced (self reported) recovery by the patients after treatment (five weeks) was used as an external criterion for clinically relevant improvement. Responsiveness was evaluated by comparing responsiveness ratios and receiver operating characteristic curves. RESULTS: The responsiveness ratio for the Harris Hip Score was high (1.70) compared with walking speed (0.45), pain during walking (0.66), and the subscales of the SF-36-"bodily pain" (0.42) and "physical functioning" (0.36). The area under the curve also was highest for the Harris Hip Score (0.92) compared with walking speed (0.71), pain during walking (0.73), and the SF-36 subscales-bodily pain and physical functioning (both 0.66). CONCLUSION: The Harris Hip Score is more responsive than the test of walking speed, pain, and subscales for function of the SF-36 in patients with OA of the hip. The Harris Hip Score seems to be a suitable instrument to evaluate change in hip function in patients with OA of the hip.

Civil unrest and ocular trauma.

The incidence and causes of ocular trauma among Israeli troops serving in the West Bank and Gaza between 1987 and 1989 was investigated. Of the 985 soldiers who were reported injured, 11.3% (111) were reported to have suffered from injuries to the eye. Although most of the soldiers were supplied with some kind of protective gear, only 27% reported that they received eye protection; none used this protection at the time of injury. Fifty-seven percent of the injuries were caused by stones and 38% by flying glass; 14.6% of soldiers suffered bilateral eye injuries. Only 12.1% of those injured wore corrective lenses. Although only 5% were originally reported to have suffered moderate to severe injuries, 38% complained of residual vision impairment. Better eye protection and enforcement of orders to use such gear would reduce the number and severity of ocular injuries.