an important additional dimension. In birds, sexual dimorphism in singing and song learning varies greatly among species, and sex differences in brain morphology are the most extreme documented in any vertebrate [2,3]. Differences in female song-learning strategies might be even greater than those observed in male vocal learning, ranging from no learning to learning as much as males do [3,4]. S...

Detection of rain/no-rain condition on the ground is an important for application of radar rainfall algorithms. A radial basis function (RBF) neural network-based scheme for rain/no-rain determination on the ground using vertical profiles of radar data is described in this paper. Evaluation based on WSR-88D radar over central Florida indicates that rain/no-rain condition can be inferred fairly ...

Gravity ventilators rely simply on air buoyancy to extract air and are widely used to exhaust air contaminants and heat from workplaces using minimal energy. They are designed to maximize the exhaust flow rate, but the rain penetration sometimes causes malfunctioning. In this study, the characteristics of rain penetration through a ventilator were examined as a preliminary study to develop a ve...

We investigated whether song types function as fundamental units of song variation in song sparrows, Melospiza melodia. As the size of a male song sparrow's repertoire increases, so does the mean similarity of his song types, as measured by the sharing of minimal units of production (MUPs). It follows that if MUP similarity is important perceptually, then small repertoires (of dissimilar song t...

Though warm rain from low-level liquid clouds contributes significantly to the global precipitation and water cycle, it has been missed or underestimated by satellite remote sensing techniques. IR techniques miss all warm rain because they rely on cloud top temperature. Over land, passive microwave techniques miss all warm rain because they rely on ice scattering at high frequency channel. Over...

BACKGROUND Birdsong is a popular model system in research areas such as vocal communication, neuroethology or neuroendocrinology of behaviour. As most research has been conducted on species with male-only song production, the hormone-dependency of male song is well established. However, female singing and its mechanisms are poorly understood. METHODOLOGY/PRINCIPAL FINDINGS We characterised th...

Measurements of rain attenuation over an earth-space path at Kolkata (22°34' N, 88°29' E), India, have been carried out since June 2004 by receiving a Ku-band signal from the satellite NSS-6 (geostationary at 95 E). The instantaneous attenuations are estimated from the point rain rates measured with an optical raingauge and using the Simple Attenuation Model (SAM). The estimated values closely ...

Song is a fundamental component of territory defense and mate attraction in birds, and androgens (like testosterone) are known to play a key role in controlling it. However, little is known about how differences in testosterone levels between males translate into inter-individual song variation. Indeed, testosterone could affect both the motivation to sing and the structure of song itself. Here...

The relationship between fleshy-fruited indigenous species and adventive weeds in the diet of 500 mist-netted birds was studied in forest remnants of differing size and degree of modification. Fruit abundance peaked in March and April, and most fruit was either red/orange or purple/black. The physical parameters of adventive and indigenous fruits were not significantly different. Six of the 15 ...

Precisely timed behaviors are central to the survival of almost all organisms. Song is an example of a learned behavior under exquisite temporal control. Song tempo in zebra finches (Taeniopygia guttata) is systematically modified depending on social context. When male zebra finches sing to females (directed), it is produced with a faster motor pattern compared with when they sing in isolation ...