Mungbean yellow mosaic virus (MYMV) is a disastrous pathogen of mungbean. It is widespread in most of southern India and no complete resistance has been identified among its commercial cultivars. Two isolates of MYMV, representing its diversity, were used to assess and characterize the susceptibility reaction of all the three species of Vigna. The seeds were agroinoculated with the virus and the presence of the viral DNA was confirmed after 12 d by reverse transcriptase-polymerase chain reaction (RT-PCR) analysis after which the plants were monitored for the expression of symptoms. All of the 20 accessions of Vigna radiata and ten accessions of Vigna mungo were systemically infected with MYMV, and they all produced typical symptoms. On the other hand, the 24 accessions of Vigna umbellata were found to be resistant to both the isolates. For additional affirmation, three representative accessions of V. radiata and V. mungo and all the accessions of V. umbellata were agroinoculated, and quantitative RT-PCR was performed for the quantitative detection of the MYMV. The mRNA transcripts of MYMV were detected in V. radiata and V. mungo plants but not in the V. umbellata plants. Researching the molecular basis of the resistance in V. umbellate against MYMV might definitely be very constructive for developing resistant varieties of mungbean on a commercial scale. This genetic quality offering resistance to MYMV could also be incorporated into V. radiata/V. mungo by means of interspecific crosses.

An investigation was carried out to quantify and characterize the corrosion behavior ofAZ61A magnesium alloy joints. Extruded 6-mm-thick Mg alloy plates of AZ61A grade werebutt-welded using a solid-state, environmentally cleaner welding process, the frictionstir welding process. The weld specimens underwent immersion, salt spray, pitting andgalvanic corrosion tests in order to quantify and characterize the corrosion rates of thewelds with the influence of different pH values, chloride ion concentrations and thecorrosion time. The corrosion rates, microstructure, scanning electron microscopy andX-ray diffraction analysis concluded the optimum parameters for the usage of the magnesiumalloy welds for the best service applications.

An important metallurgical difficulty in arc welding of high-strength aluminum alloys isformation of solidification cracking. In this work, an attempt is made to reduce thesolidification cracking in welding of aluminum alloys through vibratory treatment. Thematerial used for the investigation is AA2014 aluminum alloy, which is highly prone tosolidification cracking. Vibratory treatment was carried out in the frequency range of 100Hz to 3700 Hz. Weldments made with and without vibratory treatment were compared usingweld cracking tests and other characterization tests such as microstructural analysis. Thetest results show that by applying vibratory treatment, solidification cracking can belargely controlled in arc welding.

The effects of salt stress on the growth, nodulation and N accumulation during the vegetative phase was studied in chickpea (Cicer arietinum). Growth and N accumulation were adversely affected by salinity. The larger control plants produced new nodules but the existing nodules on stressed plants grew larger than those of control plants. All plants had similar %N contents but the total plant N was less in stressed plants due to the reduced growth of these plants. Reduced plant vigour was the primary effect of salt stress and was mediated through processes other than symbiotic N fixation.

In a long-term fertility study it was observed that judicious use of chemical fertilizers maintained the levels of soil pH, total N, organic C, CEC and exchangeable Ca. Highest accumulation of exchangeable Ca and Mg was found in the 40–60 cm layer. Absence of Mg and K from the fertilizer schedule resulted in a decrease in the amounts of those elements in the soil. Profile CEC and exchangeable Ca were not affected much by the application of K or trace elements. Compared with adjacent grass fallow or virgin bush land, only the values of C/N ratio, CEC and exchangeable Mg decreased on cultivation. All the crops responded well to fertility levels but not to K; trace element response was confined to cotton and groundnut.

There is evidence that health care providers located in communities with relatively large uninsured populations face financial difficulties because of low service demand and high levels of uncompensated care. Data on 4,920 physicians from the 2000–2001 Community Tracking Study Physician Survey and from 25,637 adults from the 2003 Community Tracking Study Household Survey were used to analyze whether the relative size of the local uninsured population is associated with the level of career satisfaction and the quality of care provided by physicians and to assess whether patient trust is associated with the level of community uninsurance. The results indicate that the proportion of uninsured adults in a given community is negatively related to physicians’ career satisfaction and the perceived quality of health care provided. Community uninsurance is also negatively related to patient trust in their doctor and positively related to whether insured patients believed that their doctor was influenced by rules from health insurance companies. Physicians in communities with relatively large uninsured populations may have lower career satisfaction and lower perceptions of the quality of care provided due to financial difficulties. Patients in these communities are also less likely to trust their physician.

This paper presents a detailed analysis of 80 type III radio bursts, two noise storms and 10 type II radio bursts observed in the 30-80 MHz range with the new radio spectrograph (Madurai Solar Radio Spectrograph) when it was operated on a daily basis during the periods December 1997 — April 1998 and August 1998. Results from statistical analysis of type III bursts are in agreement with earlier results. Employing a technique of separating the background continuum of noise storms show that the continuum is produced by electron accumulated from the preceding bursts. Also it is seen that the number of occurrences of type I bursts is maximum during the maximum of the background continuum. Comparison of records of type II bursts from MSRS with other spectrographs (Culgoora & Hiraiso) for the same bursts indicate that the sensitivity of the MSRS at low frequencies is much better than the other spectrographs.

An international Low Frequency VLBI Network (LFVN) has been organized for observations at 327 MHz and 1665 MHz frequencies with MARK-II and S2 recording terminals. Data on the interplanetary medium and spike-like solar bursts were obtained in first preliminary experiments.

The effect of sulfur and hydrogen plasma treatment on the Schottky barrier and photoluminescence (PL) properties of p-InP is reported. Both the treatments increase the barrier height of Au/p-InP diodes and band to band PL. This is explained as being due to a shift in the surface fermi level position towards the P vacancy related pinning level in the top half of the band gap. The H+ treatment passivates the shallow and deep levels as observed from the C-V depth profile and PL respectively.