Ge(1-x) Mn(x) clusters: central structural and magnetic building blocks of nanoscale wire-like self-assembly in a magnetic semiconductor.

Controlled nanoscale self-assembly of magnetic entities in semiconductors opens novel perspectives for the tailoring of magnetic semiconductor films and nanostructures with room temperature functionality. We report that a strongly directional self-assembly in growth direction in Mn-alloyed Ge is due to a stacking of individual Ge(1-x)Mn(x) clusters. The clusters represent the relevant entities for the magnetization of the material. They are formed of a core-shell structure displaying a Mn concentration gradient. While the magnetic moments seem to be carried by the shells of the clusters, their core is magnetically inactive.

Clustering in a precipitate-free GeMn magnetic semiconductor.

We present the first study relating structural parameters of precipitate-free Ge0.95Mn0.05 films to magnetization data. Nanometer-sized clusters--areas with increased Mn content on substitutional lattice sites compared to the host matrix--are detected in transmission electron microscopy analysis. The films show no overall spontaneous magnetization at all down to 2 K. The TEM and magnetization results are interpreted in terms of an assembly of superparamagnetic moments developing in the dense distribution of clusters. Each cluster individually turns ferromagnetic below an ordering temperature which depends on its volume and Mn content.

Ancient Indian bacteriology.

An attempt has been made in this paper to disseminate the formation of basic knowledge of bacteriology in ancient India. In the aetiology of many diseases microbial relation plays a role which was realized by the modern medicine only a century ago.

Pharmaco - therapeutics of dasemani drugs.

The author scans in this paper the drug classification of Ayurvedic science grouped under two distinct heads of Botanical and therapeutic planes with modern equivalents. Also he throws some light on grouping of drugs done by Caraka the author of Caraka Samhita with special references to anti-inflammatory, Anti-haemorridal and Anti-asthmatic Dasemani drugs.

Ayurveda in perspective.

Unlike the other systems of medicine, Ayurveda is a knowledge that should be learnt and preserved by each and every human being. Besides presenting some of the basic theories of Ayurveda the negligence shown in understanding the significance of this system, the inadequate resource allocation an down right disregard by the Government in its development is exposed.