Search

The Chinese Alashan Left Banner White Cashmere goat is a subpopulation of the Inner Mongolian Cashmere goat which produced a very fine cashmere. In the last years, textile industry addressed particular attention in the cashmere produced by the youngest cashmere goats especially on changes in fleece characteristics during the first year of life. This study described the coat development in Chinese Alashan Left Banner White Cashmere goat kids in the first year of life, from three months of age until the first combing season. Twelve does born on January 2009 were selected at random from the herd located in the Station for Livestock Improvement of Alashan. Fleece sampling started at April 2009 and was repeated monthly till February 2010. The analysis of variance showed that the length of down hair and guard hair, the cashmere diameter and coefficient of variation of diameter were significantly influenced by the age. Furthermore, the study revealed that the kids bear the down hair from birth. The length of the down hair increased for the first five months of life until the first moult in June-July at around 5–6 months of age. On the contrary, no shedding of the guard hair was observed. In fact, the guard hair of the kids continued to increase in length until the goats were 13 months old. These results suggest an asynchronous pattern of moulting of the birth double-coat. Moreover, the baby down hair shedded during the first moult was finest (on average

The multiexciton properties of extrinsic centers from AlGaAs layers on Ge and Si substrates are addressed. The two photon cascade is found both in steady state and in time resolved experiments. Polarization analysis of the photoluminescence provides clearcut attribution to neutral biexciton complexes. Our findings demonstrate the prospect of exploiting extrinsic centers for generating entangled photon pairs on a Si based device. © 2013 AIP Publishing LLC.

We show that the epitaxial growth of height-controlled GaAs quantum dots, leading to the reduction of the inhomogeneous emission bandwidth, produces individual nanostructures of peculiar morphology. Besides the height controlled quantum dots, we observe nanodisks formation. Exploiting time resolved and spatially resolved photoluminescence we establish the decoupling between quantum dots and nanodisks and demonstrate the high optical properties of the individual quantum dots, despite the processing steps needed for height control. © 2013 AIP Publishing LLC.

Nowadays, many visual surveillance systems exploit pan/tilt/zoom (PTZ) cameras to increase the field of view of a surveyed area. The background subtraction technique is widespread to detect moving objects with a high accuracy using one stationary camera. Extending such algorithms to work with moving cameras requires to have a background mosaic at one's disposal. Many solutions using mosaic background subtraction have been proposed, which offer real time capabilities or high quality of the detected objects. However, most of them rely on prior assumptions which limit the camera motion or the algorithm to work with a depth field of view only. In this work we propose some innovative solutions to achieve a real time mosaic background apt to work with existing background subtraction algorithms to yield excellent foreground object masks. Extensive experiments accomplished on challenging indoor and outdoor scenes permit to assess the quality of the mosaic as well as of the detected moving masks.

We show that the epitaxial growth of thin layers of AlGaAs on Ge and Si substrates allows to obtain single photon sources by exploiting the sparse and unintentional contamination with acceptors of the AlGaAs. Very bright and sharp single photoluminescence lines are observed in confocal microscopy. These lines behave very much as single excitons in quantum dots, but their implementation is by far much easier, since it does not require 3D nucleation. The photon antibunching is demonstrated by time resolved Hanbury Brown and Twiss measurements.