Chemistry of the mandibular gland secretion of the Indian beePithitis smaragdula

The mandibular glands of the stem-nesting Indian beePithitis smaragdula contain a mixture of salicylaldehyde, citronellyl acetate, geranyl acetate, pentadecane, heptadecane, ethyl tetradecanoate, and ethyl hexadecanoate. Salicylaldehyde is reported for the first time from a hymenopterous source. The secretion, emitted when the bee is disturbed, is rubbed with the legs over the bee's body and the disturbing object. The reactivity of some of the components in combination with the bee's behavior make the glandular exudate an effective defensive secretion.     

Development of fuels and structural materials for fast breeder reactors

Fast breeder reactors (FBRs) are destined to play a crucial role in the Indian nuclear power programme in the foreseeable future. FBR technology involves a multi-disciplinary approach to solve the various challenges in the areas of fuel and materials development. Fuels for FBRs have significantly higher concentration of fissile material than in thermal reactors, with a matching increase in burn-up. The design of the fuel is an important aspect which has to be optimised for efficient, economic and safe production of power. FBR components operate under hostile and demanding environment of high neutron flux, liquid sodium coolant and elevated temperatures. Resistance to void swelling, irradiation creep, and irradiation embrittlement are therefore major considerations in the choice of materials for the core components. Structural and steam generator materials should have good resistance to creep, low cycle fatigue, creep-fatigue interaction and sodium corrosion. The development of carbide fuel and structural materials for the Fast Breeder Test Reactor at Kalpakkam was a great technological challenge. At the Indira Gandhi Centre for Atomic Research (IGCAR), advanced research facilities have been established, and extensive studies have been carried out in the areas of fuel and materials development. This has laid the foundation for the design and development of a 500 MWe Prototype Fast Breeder Reactor. Highlights of some of these studies are discussed in this paper in the context of our mission to develop and deploy FBR technology for the energy security of India in the 21^st century.     

Due date selection procedures for job-shop simulation

This paper introduces a comprehensive classification of due date selection procedures from which three major categories are derived. Emphasis is centered on providing a summary of selection procedures in a form that can be readily used by both researcher and practitioners. The paper concludes with a review and critique of recent discrete digital computer simulation studies concerning the impact of due date assignment procedures on shop performance and priority scheduling rules.     

Indentation study of cadmium oxalate trihydrate single crystals

Vickers microhardness indentation studies have been made on the as-grown (¯2¯21), (110) and (001) planes, and on the only cleavage plane (1¯10) of gel-grown cadmium oxalate trihydrate single crystals. The material chipping off and slip lines observed around indentation figures have been discussed. The anisotropy in microhardness of the crystals is indicated.     

Simplification of fuzzy switching functions

This paper is concerned with the study of simplification of fuzzy switching functions. A novel algorithm for generating all fuzzy prime implicants is introduced, followed by a new method of simplification of fuzzy switching functions. This algorithm is then reduced to a simple algorithm that produces only those fuzzy prime implicants that are essential. There areonly two other valid techniques for the minimization of fuzzy switching functions in the literature,^(1,2) and those methods are not very suitable for computerized application. Thus, the principal advantages of this technique are the new concept of direct simplification via essential fuzzy prime implicants (without generation of all of the fuzzy prime implicants), and the fact that the algorithm is the first one to be suitable for efficient computer implementation.On leave from the Computer Science Department, New Mexico Institute of Mining and Technology, Socorro, New Mexico.     

Lipogenesis by intact hepatocytes from normal and diabetic rats

Intact hepatocytes isolated from livers of diabetic rats demonstrate the characteristic decreased lipogenic capacities as compared to normal. Administration of insulin to diabetic rats restores these capacities to near normal levels. The results emphasize the potential that the hepatocyte system has for the study of hormonal regulation of lipogenesis.     

Pericardial tamponade secondary to sudden steroid withdrawal in chronic rheumatoid arthritis

A patient with chronic rheumatoid arthritis was admitted to the hospital with cervical fracture. Two weeks after acute steroid withdrawal, she was noted to have pleural effusion, and signs and symptoms of acute pericardial tamponade. An open partial pericardiectomy and drainage relieved the symptoms. The sequence of events suggests that rapid steroid withdrawal might have precipitated rapid accumulation of pleural and pericardial fluid.