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We investigated the etiology of anterior segment eye abnormalities caused by heterozygous null mutations in PAX6 by studying the small eye Pax6+/- mouse model. Histological analysis of Pax6+/- embryos showed that the lens was developmentally delayed, with signs of degeneration. Pax6+/+ [equivalence] Pax6+/- chimeras, which are mixtures of wild-type and heterozygous cells, revealed two cell autonomous defects of the heterozygous lens: Pax6+/- cells are less readily incorporated into the lens placode than wild type, and those which are incorporated into the lens are not maintained efficiently in the lens epithelium. The lens of chimeric embryos is therefore predominantly wild type by E16.5, while, in contrast, heterozygous cells contribute normally to all other chimeric eye tissues, into adulthood. Surprisingly, eye size and defects of the iris and cornea are corrected in fetal and adult chimeras with up to 90% mutant cells; correction of the whole eye phenotype correlates with correction of the lens genotype. The lens has been shown to produce growth factors and drive development of the ciliary body, iris, and cornea. We postulate that reduction of Pax6 dosage compromises the ability of the lens to instigate inductive interactions that organize the anterior segment. Our data suggest that small eyes, aniridia, and corneal opacities are all consequences of the lens defects. This has clinical relevance for human aniridia PAX6+/- phenotypes and suggests the possibility of therapy.

EUROPA DONNA, a non-profit-making organisation, is a pan-European movement against breast cancer; it is a coalition that is active in 29 countries, each organised into national independent Fora. In each Forum, a postal survey was conducted between 2001 and 2002. A standardised questionnaire was used to collect information about Forum characteristics and activities, and perceptions of the adequacy of the local health service in relation to the prevention, diagnosis and treatment of breast cancer. Twenty-seven Fora (93%) participated in the survey. The results show the heterogeneity between the Fora in the services offered and activities in the different countries. The Fora also perceived a range of deficiencies in the prevention, diagnosis and treatment of breast cancer within their national health systems. These results highlight the importance of a coalition to establish a consensus among the Fora, and the need for coordinated initiatives in different European countries. [Copyright &y& Elsevier]

Abstract: The development of room temperature infrared (IR) detectors for wavelengths beyond NIR will open up many applications that are currently limited due to cooling requirements. Three approaches are discussed, which show promise for room temperature IR detection. Tunneling quantum dot (QD) detector, utilizes a tunneling barrier in order to block the dark current while permitting the photocurrent to pass through due to resonance effects, has shown room temperature response for a detector operating at 6 and 17μm. The PbS QDs in a dielectric medium utilizes electronic polarizability of QDs, sensing only the variations of the radiation intensity, operating at ambient temperature. This method allows narrow multiple response bands. A GaAs/AlGaAs heterojunction detector, utilizing light, heavy and split-off hole transition in a p-doped semiconductor, shows a threshold of 3.4μm operating up to 330K. [Copyright &y& Elsevier]

Abstract: As novel applications using terahertz radiation are developed, there is an increased demand for sensitive terahertz detectors. This has led to new approaches for enhancing the response of terahertz detectors. Results were recently reported on the terahertz response of a p-type AlGaAs/GaAs, n-type GaAs/AlGaAs, n-type GaN/AlGaN, and p-type GaSb/GaSb Interfacial Workfunction Internal Photoemission detectors. The use of surface plasmon coupling due to metal grids is one approach discussed here to enhance the performance of these terahertz detectors. Due to the greatly enhanced near fields of the plasmons, the absorption would be increased leading to improved detectors. Results are presented on the enhancement of absorption by plasmon effects in a thin film coupled with a metal grid. [Copyright &y& Elsevier]