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AbstractBroad spectrum pesticides are molecules which act across a range of pests. The popular class of compounds with this property are thiacloprid, nitenpyram, ethaboxam, silthiofam, 3,3,4,4-tetrachloro tetrahydro thiophene etc. Interestingly, all these compounds possess at least one heterocyclic ring like thiophene, furan, and imidazole etc. in their structure. Among the synthons available for synthesis of neonicotinoids, tetrachlorothiophene is unique. The bulk scale synthesis of tetrachlorothiophene is reported only by cyclization of hexachloro-1,3-butadiene. The reaction yields of synthesis of this synthon are around 45%. We report silica-coated magnetic nanoparticles as a generic catalyst for this cyclization reaction yielding tetrachlorothiophene. The yield improvement is 50–60% more compared to original yield. The distillate crystallization in methanol yielded >98% pure compound compared to typical 90–92% in conventional process. The proposed reaction uses reusable silica-coated 40 nm size magnetic nanoparticles and the catalyst itself is of low cost and reaction conditions are mild.

AbstractSystematic and standardized approach for monitoring and evaluating disease control programs is needed. The conventional sample survey methods are expensive, time consuming and need a great deal of resources. Lot Quality Assurance Sampling (LQAS) technique, originally a quality control tool in an industry, which was tried successfully for monitoring and evaluating immunization programs, leprosy, tuberculosis, sleeping sickness etc., control programs. Literature review suggests that all, except three, studies employing LQAS survey methodology used single sampling plan and normal approximation method to compute sample size. Hence, there is a need to develop formulae to obtain nomograms on sample sizes as ready reckoner when the variable of interest follows Hypergeometric distribution. The methods for sample size calculation using LQAS methodology under single/double, multiple sampling plans are provided separately for Hypegeometric distribution with/ without considering the Power are developed. Pragmatic solutions for the sample size and the corresponding acceptable number ‘d’ are obtained for diff erent sampling plans such as single, double and multiple sampling plans

The article looks at the fruit production in India. It cites that the country is the second largest producer of fruits internationally with about 45.203 million tons of total production in 2002-2003. A brief history of fruit culture in the country is presented. It tackles the socio-economic significance, volume of production and export trade of several fruits including mango, banana, citrus and papaya in India.

To adapt and develop a method for finding out what proportion of the variation among small areas in the number of births to married women is excess (systematic) variation over and above the chance (random) variation.

Abstract: Several cultivars of hybrid seed geranium (Pelargoniumhortorum Bailey), previously shown to be recalcitrant in culture, produced somatic embryos at high frequency when explants were co-cultivated with a morphogenesis promoting bacterium. This bacterium was isolated as an in vitro contaminant from cultures of geranium seedling explants and identified as belonging to the genus Bacillus and species circulans. Co-cultivation of hypocotyl explants with the bacterium promoted somatic embryo formation and improved both the frequency and quality of somatic embryos. In the cultivar Ringo Rose, the least responsive among the cultivars screened, the embryogenic response was more than four times that of axenic cultures. Nearly 70% of these embryos converted into plantlets, while the somatic embryos induced under axenic conditions developed poorly and plantlet formation was inconsistent. Among the different treatments of bacterial culture tested (autoclaved culture, culture filtrate, sonicated bacterial culture, sonication of bacterial culture followed by filtration, HPLC fractionation of crude bacterial lysate), only two HPLC fractions promoted embryogenesis to a marginal degree. Co-cultivation of the explants with bacterium during the first week of induction was crucial for obtaining high-frequency embryogenesis, indicating the role of bacterial stimuli during the induction process.

Extensive work has been conducted at Gulf Research & Development Company over the past 5 years to assess the feasibility of commercializing chemical coal cleaning technologies. Elements of this work are reviewed in this paper. It is concluded that the use of chemical cleaning will await the development of markets for premium coals and the start of new market-oriented strategies by coal companies. The trend by electric utilities toward the use of more efficient fuels and the need to pay out high cost coal reserves may force coal companies to develop premium fuels for improving market share. Significant use of chemical methods in coal preparation is a distinct possibility in the future because of developments now under way in the use of coal as an alternative hydrocarbon feedstock in chemicals and fuels applications. The potential for chemical preparation of low-ash and low-sulfur coal for these new applications is discussed.

Abstract: Somatic embryos were initiated with mature seeds of neem (Azadirachta indica A. Juss.) when cultured on Murashige and Skoog's medium supplemented with thidiazuron (TDZ). Regeneration occurred via somatic embryogenesis: direct embryo formation and through an intermediary callus phase. TDZ was very effective and induced somatic embryogenesis across a wide range of concentrations (1–50 µm). However, somatic embryogenesis was accompanied by callus formation at concentrations of 20 µm and above. Cell suspension cultures were established with the TDZ-induced callus and groups of large cell clumps were formed within 2–3 weeks. Plants were regenerated from both directly formed somatic embryos and somatic embryos derived from cell suspensions plated on semisolid medium devoid of growth regulators. Regenerated plantlets continued to grow after transfer to a greenhouse environment and were similar phenotypically to zygotic seedlings. This simple regeneration system may be beneficial for mass propagation of selected elite clones of neem.

TDZ (N-phenyl-N’-1,2,3-thidiazol-5-ylurea) is a substituted phenylurea compound which was developed for mechanized harvesting of cotton bolls and has now emerged as a highly efficacious bioregulant of morphogenesis in the tissue culture of many plant species. Application of TDZ induces a diverse array of cultural responses ranging from induction of callus to formation of somatic embryos. TDZ exhibits the unique property of mimicking both auxin and cytokinin effects on growth and differentiation of cultured explants, although structurally it is different from either auxins or purine-based cytokinins. A number of physiological and biochemical events in cells are likely to be influenced by TDZ, but these may or may not be directly related to the induction of morphogenic responses, and hence, the mode of action of TDZ is unknown. However, the recent approaches applied to study the morphogenic events initiated by TDZ are clearly beginning to reveal the details of a variety of underlying mechanisms. Various reports indicate that TDZ may act through modulation of the endogenous plant growth regulators, either directly or as a result of induced stress. The other possibilities include the modification in cell membranes, energy levels, nutrient uptake, or nutrient assimilation. In this review, several of these possiblities are presented and discussed in light of recently published studies on characterization of TDZ-induced morphogenic effects.

In vitro regeneration in chickpea (Cicer arietinum L.) was achieved by direct culture of mature seeds on Murashige and Skoog (MS) medium supplemented with either N-phenyl-N'(-1,2,3-thidiazol-5-yl) urea (thidiazuron, TDZ) or N6-benzylaminopurine (BAP). Multiple shoots formed de novo without an intermediary callus phase at the cotyledonary notch region of the seedlings within 2 to 3 weeks of culture initiation. TDZ was found to be more effective compared to BAP as an inductive signal of regeneration. The former induced multiple shoot formation at all the concentrations tested (1 µM to 100 µM), although, maximum morphogenic response was observed at 10 µM concentration. Addition of naphthaleneacetic acid (NAA) alone or in combination with BAP to the MS medium failed to invoke a similar response. When the TDZ supplemented medium was amended with L-proline, the resultant regenerants were mostly somatic embryos. Histological investigations confirmed the switch in the regeneration pathway from directly formed adventitious shoots to embryogenesis. For obtaining plantlets, adventitious shoots were rooted on MS medium supplemented with 2.5 µM NAA; somatic embryos were germinated and established on MS medium. Normal plants were regenerated from both adventitious shoots and somatic embryos and transferred to soil.

The ability of forchlorfenuron (CPPU), a substituted phenylurea compound, for inducing somatic embryogenesis in peanut (Arachis hypogaea L.) seedlings has been demonstrated. CPPU promoted somatic embryogenesis at a range of concentrations in all three peanut cultivars tested. Embryogenic response was dependent on applied CPPU concentrations. Exposure of seedlings for only two days to CPPU induced somatic embryogenesis, but the most effective treatment was to induce seed germination on media supplemented with either 2.5 or 4.0 µM CPPU and to maintain the seedlings on the same medium. Number of somatic embryos and the frequency of embryogenesis was higher for younger seedlings (up to 9 days), regardless of the CPPU concentrations and seedlings older than 21 days failed to produce somatic embryos. Removal of cotyledons from the seeds drastically reduced the embryogenic potential of the seedlings. Somatic embryos developed into whole plants following their separation and subculture on a medium lacking growth regulators. The induction of somatic embryos using CPPU as a sole growth regulator may provide a useful system to study the role of this compound in plant morphogenesis.

The cv Ringo Rose of hybrid seed geranium (Pelargonium x hortorum Bailey), previously shown to be recalcitrant in culture, produced somatic embryos when cotyledonary explants were cultured on regeneration medium containing thidiazuron (TDZ), forchlorfenuron (CPPU), or a combination of indole-3-acetic acid and N6 benzylaminopurine (IAA+BAP). Amendment of the basal medium with TDZ (0.5 µM) was the most effective treatment. Addition of amino acids to the medium promoted the growth of somatic embryos. Retention of the proximal region of the cotyledon was crucial for regeneration, but the removal of the distal 1/3 to 1/2 cotyledon had no significant effect on somatic embryogenesis. Cotyledonary explants formed somatic embryos in higher frequency and much earlier than hypocotyl explants cultured on the same medium. The somatic embryos induced on cotyledonary explants were germinated on basal medium. More than 70% of the somatic embryos were converted into plants and transferred to soil

ABSTRACTAssessment of 12 microscopy centers in a tuberculosis unit by blinded checking of eight sputum smears selected by using a lot quality assurance sampling (LQAS) method and by unblinded checking of all positive and five negative slides, among the slides examined in a month in a microscopy centre, revealed that the LQAS method can be implemented in the field to monitor the performance of acid-fast bacillus microscopy centers in national tuberculosis control programs.

The article offers travel tips for Makati, Philippines, and includes information on parks and gardens, water fountains and the Greenbelt Chapel.