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Part 7, Chapter 32 of the book "Potato Biology and Biotechnology: Advances and Perspectives" is presented. It explores the importance of the use of soil-free techniques on producing seed potatoes. It also provides information on the developments of the methods for the soil-free production of potato crops.

Chapter 16 of the "Handbook of New Technologies for Genetic Improvement of Legumes" is presented. It discusses the development of tissue culture and genetic transformation of peanut (Arachis hypogaea L.) as well as the possible applications of this development in the improvement of this legume crop. Transformation involves the precise transfer of foreign deoxyribonucleic acid (DNA) sequences into plant cells using Ti plasmids.

Lentil (Lens culinaris Medik.) is an important winter season grain legume grown worldwide in semi-arid regions. Although lentil has been an important crop for centuries, very little attention has been paid in terms of genetic research until recently. A few centers around the world, including India, have started systematic work on genetic and linkage studies in lentil. Inheritance studies involving about three-dozen morphological markers have been completed. A comprehensive linkage map involving molecular markers and a few morphological markers has been developed. In the present paper, an effort has been made to comprehend the current status and recent advances made in terms of genetic, cytogenetic, linkage studies and other related aspects in lentil. The strategies for future research have also been outlined [ABSTRACT FROM AUTHOR]

Spatial data mining is a demanding field since huge amounts of spatial data have been collected in various applications, ranging form Remote Sensing to GIS, Computer Cartography, Environmental Assessment and Planning. Although there have been efforts for spatial association rule mining, but mostly researchers discuss only the positive spatial association rules; they have not considered the spatial negative association rules. Negative association rules are very useful in some spatial problems and are capable of extracting some useful and previously unknown hidden information. We have proposed a novel approach of mining spatial positive and negative association rules. The approach applies multiple level spatial mining methods to extract interesting patterns in spatial and/or non-spatial predicates. Data and spatial predicates/association-ship are organized as set hierarchies to mine them level-by-level as required for multilevel spatial positive and negative association rules. A pruning strategy is used in our approach to efficiently reduce the search space. Further efficiency is gained by interestingness measure. [ABSTRACT FROM AUTHOR]

100 MeV Si+7 irradiation induced modifications in the structural and magnetic properties of Mg0.95Mn0.05Fe2O4 nanoparticles have been studied by using X-ray diffraction, Mössbauer spectroscopy and a SQUID magnetometer. The X-ray diffraction patterns indicate the presence of single-phase cubic spinel structure of the samples. The particle size was estimated from the broadened (311) X-ray diffraction peak using the well-known Scherrer equation. The milling process reduced the average particle size to the nanometer range. After irradiation a slight increase in the particle size was observed. With the room temperature Mössbauer spectroscopy, superparamagnetic relaxation effects were observed in the pristine as well as in the irradiated samples. No appreciable changes were observed in the room temperature Mössbauer spectra after ion irradiation. Mössbauer spectroscopy performed on a 12 h milled pristine sample (6 nm) confirmed the transition to a magnetically ordered state for temperatures less than 140 K. All the samples showed well-defined magnetic ordering at 5 K, whereas, at room temperature they were in a superparamagnetic state. From the magnetization studies performed on the irradiated samples, it was concluded that the saturation magnetization was enhanced. This was explained on the basis of SHI irradiation induced modifications in surface states of the nanoparticles. [ABSTRACT FROM AUTHOR]

In general, the action of intracellular second messengers, 3′:5′-cyclic adenosine monophosphate (cAMP) and 3′:5′-cyclic guanosine monophosphate (cGMP), are terminated by cyclic nucleotide phosphodiesterase (PDE). In most mammalian tissues, PDE exists in multiple forms that differ in subcellular localization, catalytic, regulatory, and immunological properties (1-4). One of these forms of enzyme is activated by Ca2+ and calmodulin (CaM) and has a lower apparent Km for cGMP than for cAMP and higher Vmax for cAMP than for cGMP (2,5,6). This CaM-dependent cyclic nucleotide phosphodiesterase (CaMPDE) is widely distributed among mammalian tissues and other eukaryotes (7-11). CaMPDE is one of the most intensively studied and best characterized PDEs (12-19). [ABSTRACT FROM AUTHOR]

Posttranslational modification has long been recognized as a way in which the properties of proteins may be subtly altered after synthesis of the polypeptide chain is complete. Amongst the moieties most commonly encountered covalently attached to proteins are oligosaccharides, phosphate, acetyl, formyl, and nucleosides. Posttranslational covalent modification of protein by phosphorylation is one of the most prevalent and best understood mechanisms employed in cellular regulation (1-9). Protein kinases catalyze the transfer of the γ-phosphoryl group of adenosine triphosphate (ATP) to an acceptor protein substrate. The activity of the enzyme is determined by the transfer of 32P (labeled γ-phosphate) from [γ-32P] ATP to protein substrate [ABSTRACT FROM AUTHOR]

Over a century ago, Paul Ehrlich proposed the magic bullet theory of targeting therapeutic agents to specific tissues in order to increase their efficacy and reduce systemic toxicity. Because of their selectivity and the rapid development of hybridoma technology in the 1980s, monoclonal antibodies either alone or linked to a wide range of therapeutic agents such as radionuclides, drugs, toxins, enzymes, and growth factors have been used for diagnosis and therapy of diseases, particularly cancer. However, inherent problems with the monoclonal antibodies themselves, coupled with the heterogeneous structure and pathophysiology of solid tumours, reduce effective delivery following systemic administration. The more recent development of phage technology and antibody engineering is now addressing these problems by allowing the creation of antibodies with required characteristics for specific purposes. Antibody-directed enzyme-prodrug therapy (ADEPT) is a complex two-phase system in which an enzyme is targeted to the tumor site by an antibody, where it selectively activates a relatively nontoxic prodrug to a potent cytotoxic agent. This system has progressed from the monoclonal antibody approach to that of genetically engineered fusion proteins, in order to provide optimized molecules for clinical trials. This chapter will start by giving a brief overview of the field, concentrating on the developments in our own department using anti-CEA antibodies and the bacterial enzyme carboxypeptidase G2. This will be followed by a description of the major materials and methods involved in fusion protein production. [ABSTRACT FROM AUTHOR]

Myristoyl-CoA:protein N-myristoyltransferase (NMT) catalyzes the cotranslational transfer of myristate from myristoyl-CoA to the amino-terminal glycine residue of a number of cellular, viral, fungal, and oncoproteins (1-5). These proteins include the catalytic subunit of cAMP-dependent protein kinase, various tyrosine kinases (including pp60src, pp60yes, pp56lck, pp59fyn/syn, and cAbl), the β-subunit of calmodulin-dependent protein phosphatase (calcineurin), the myristoylated alanine rich C kinase substrate, the α-subunit of several G-proteins, and several ARF proteins involved in ADP ribosylation (1-5). A significant problem with the purification and characterization of NMT concerns the available assay procedures. The wide availability and use of peptides allow for convenient substrates. However, the existing procedures to isolate and analyze the reaction products of myristoylation, such as reverse-phase HPLC, are expensive and time-consuming (6,7). Ion-exchange column chromatography, differential solubilization, adsorption of myristoyl-CoA to acidic alumina, and ion-exchange exclusion of [3H]myristoyl peptides have been utilized as assay methods are faster and more convenient than reverse-phase HPLC (8-10). However, these procedures are still limited with respect to the number of assays that can conveniently be performed. Here we described a new rapid, reliable, and inexpensive NMT assay based on the binding of [3H]myristoyl-peptide to a P81 phosphocellulose paper matrix (11). [ABSTRACT FROM AUTHOR]

Posttranslation covalent modification of proteins by phosphorylation represents an important mechanism in the control of many cellular functions (1,2). Protein kinases catalyze the transfer of the γ-phosphoryl group of ATP to an acceptor protein substrate. The activity of the enzyme is determined by the transfer of 32P from [γ-32P] ATP to protein substrate [ABSTRACT FROM AUTHOR]

The article presents information on microwave resonant structures which are almost invariably understood as cavity resonators. Cavity resonators, in contrast to lumped resonators, have an infinite number of resonant frequencies. In the vacinity of each resonant frequency, the cavity can be approximated by an associated lumped equivalent circuit. The parameters of a resonator at microwave frequencies are essentially similar to those of a lumped-element resonator circuit at low frequencies. The article describes various coaxial and waveguide resonators. Fabrication, coupling, measurements, and applications of cavity resonators are also included.

The effects of initial emulsifier concentration and emulsification time upon the globule size distribution of new type of emulsions, called oil-in-oil emulsions (nonaqueous systems) have been studied. The time of emulsification to reach a steady state globule size increases linearly with increasing initial surfactant concentration, upto an optimum emulsifier concentration, thereafter it remains constant. The initial emulsifier concentration has little effect on the steady state globule size distribution of nonaqueous emulsions. The values of frequency function, geometric standard deviation, geometric mean diameter, mean volumesurface diameter, and globule diameter of most frequent occurrence, of emulsions have been determined. [ABSTRACT FROM AUTHOR]

The effect of some cationic surfactants on the stability of the xylene-in-water emulsion stabilized by dodecyl benzene sulphonate has been studied. The globules size was determined microphotographically. The stability of the emulsion system has been assessed by the measurement of electrokinetic potentials in presence of surfactants. The interaction energies have also been calculated and plotted as a function of interparticle distance. Flocculation studies were carried out hemocytometrically and values were correlated with electrokinetic potential. The flocculation and coalescence rate constants were determined separately in order to study the kinetics of coagulation of the system. The nature of adsorption of these surfactants has also been explained by calculating adsorption constants, value of van der Waals constant, number of binding sites, charge density and free energy of adsorption. [ABSTRACT FROM AUTHOR]

Opiates, such as morphine and heroin, exert their pharmacological effects by binding to highly specific receptor proteins on the cell surface of neuronal and nonneuronal cells. In 1973, researchers in three different laboratories demonstrated the presence of receptors specific for opiates in preparations from brain and intestine (Pert and Snyder, 1973; Simon et al., 1973; Terenius, 1973). These studies satisfied the criteria first enunciated by Goldstein et al. (1971) for a narcotic receptor that is specific for the pharmacologically active D(−) enan-tiomer of the narcotics. The existence of specific opiate receptors in brain led many scientists to look for endogenous lig-ands in the brain for which opiate receptors exist. In 1975, Hughes et al. isolated and characterized two pentapeptides (Met- and Leu-enkephalins) from bovine brain that were able to mimic the actions of morphine in the pharmacological test systems. Now, it is known that a family of more than 20 endogenous opioid receptor ligands are generated from three precursor proteins, namely, proopiomelanocortin, proen-kephalin, and prodynorphin (Evans et al., 1988). Based on the pharmacological potency and the selectivity of receptors for various opioid ligands, the receptors were classified into μ, δ, and κ receptors (Pasternak, 1986; Zukin et al., 1988). [ABSTRACT FROM AUTHOR]

The national system of education in India employs a curricular framework with a common core and other flexible components. It intends to provide access and quality of education to all. The administrative and financial controls of the system rest jointly with the union government and the state-level governments. In 1984, a program of computer literacy was started on an experimental basis in government schools. The first computer-related policy, emphasizing computer literacy, was established as a part of the National Policy on Education in 1986 and modified in 1992. Realizing all of India's intended policy goals regarding the use of computers in education will require facing several major obstacles. This paper makes suggestions for overcoming some of them. [ABSTRACT FROM AUTHOR]

The term pyridoxine is generally used to refer to the group of naturally occurring pyridine derivatives represented by pyridoxine (pyridoxol), pyridoxal, and pyridoxamine, with similar physiological actions. They are referred to as vitamin B6 vitamers. Pyridoxine is used synonymously with vitamin B6. Pyridoxal phosphate (PLP) is the major coenzymatic form of pyridoxine. There are over 100 known pyridoxal 5′-phosphate-dependent reactions, most of which are involved in the metabolism of various amino acids. Vitamin B6 plays a crucial role in the functioning of the nervous system. The putative neurotransmitters dopamine (DA), norepinephrine (NE), serotonin (5-hydroxytryptamine, 5HT), γ-aminobutyric acid (GABA), and taurine, as well as the sphingolipids and polyamines, are synthesized by PLP-dependent enzymes. There is considerable variation in the affinities of various apoenzymes for PLP. In view of this, during progressive pyridoxine deficiency, the PLP-dependent enzymes are decreased to various extents, from no decrease to almost a complete depletion. The decreases in the activities of glutamic acid and 5-hydroxytryptophan decarboxylases during pyridoxine deficiency result in the reduction of the concentrations of the neurotransmitters GABA and 5HT. [ABSTRACT FROM AUTHOR]

The effects of dispersed phase volume and particle size distribution on the rheology of oil-in-oil emulsions (nonaqueous systems) prepared with monochlorobenzene and ethylene glycol as disperse and continuous phases and polyoxyethylene sorbitan monooleate as emulsifier, have been studied. Experimental viscosity data obtained for nonaqueous emulsions appeared to fit the general equation ηrel=exp (aφ/1−kφ). The values of constant a have been found to be below the value of 2.5 for solid spheres and the hydrodynamic interaction coefficient k decreases with an increase in mean particle size. [ABSTRACT FROM AUTHOR]

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