The effect on the algebraic connectivity of a tree by grafting or collapsing of edges

AbstractLet G=(V,E) be a tree on n⩾2 vertices and let v∈V. Let L(G) be the Laplacian matrix of G and μ(G) be its algebraic connectivity. Let Gk,l, be the graph obtained from G by attaching two new paths P:vv1v2…vk and Q:vu1u2…ul of length k and l, respectively, at v. We prove that if l⩾k⩾1 then μ(Gk-1,l+1)⩽μ(Gk,l). Let (v1,v2) be an edge of G. Let G∼ be the tree obtained from G by deleting the edge (v1,v2) and identifying the vertices v1 and v2. Then we prove that μ(G)⩽μ(G∼). As a corollary to the above results, we obtain the celebrated theorem on algebraic connectivity which states that among all trees on n vertices, the path has the smallest and the star has the largest algebraic connectivity

Synthesis, structure, DNA binding and oxidative cleavage activity of ternary (l-leucine/isoleucine) copper(II) complexes of heterocyclic bases

Six ternary α-amino acid copper(II) complexes of the general formula Cu(AA)(B)(H 2O)(X) (1-6), where AA is l-leu = l-leucine (1-3) or l-ile = l-isoleucine (4-6), B is a N,N-donor heterocyclic base, viz. 2,2â²-bipyridine (bpy, 1, 4), 1,10-phenanthroline (phen, 2, 5) and dipyrido3,2:2â²,3â²-fquinoxaline (dpq, 3, 6) and X = ClO 4 - / NO 3 - have been synthesized, characterized, and their DNA binding and cleavage activity studied. The bpy and dpq complexes of l-ile (4, 6) have been structurally characterized by X-ray crystallography. The complexes show a distorted square-pyramidal (4 + 1) CuN 3O 2 coordination geometry. The one-electron paramagnetic complexes display a d-d band near 600 nm in water and show a cyclic voltammetric response due to a Cu(II)/Cu(I) couple near -0.1 V (vs. SCE) in DMF-0.1 M TBAP. All complexes are 1:1 electrolytes. Binding interactions of the complexes with calf thymus DNA (CT-DNA) have been investigated by absorption, emission, viscosity and DNA melting studies. The phen and dpq complexes are avid binders to the calf thymus DNA, giving an order: (3, 6) (dpq) > (2, 5) (phen) â« (1, 4) (bpy). The bpy complexes do not show any apparent binding to the DNA and hence show poor DNA cleavage activity. The phen and dpq complexes (2, 3, 5, 6) show efficient oxidative cleavage of pUC19 supercoiled DNA (SC-DNA) in the presence of the reducing agent 3-mercaptopropionic acid (MPA) involving hydroxyl radical ( {radical dot}OH) species, as evidenced from the control data showing inhibition of DNA cleavage in the presence of {radical dot}OH radical quenchers, viz. DMSO, mannitol, KI and catalase. © 2008 Elsevier Ltd. All rights reserved

DNA binding and oxidative cleavage activity of ternary (l-proline)copper(II) complexes of heterocyclic bases

Ternary copper(II) complexes Cu(l-pro)(B)(H 2O)(NO 3) (1, 2) where l-pro = l-proline, B is a N,N-donor heterocyclic base, viz. 2,2â²-bipyridine (bpy, 1), 1,10-phenanthroline (phen, 2), are synthesized, characterized, and their DNA binding and cleavage activity studied. The bpy complex (1) is structurally characterized by single-crystal X-ray crystallography. The complexes show the presence of a distorted square-pyramidal (4 + 1) CuN 3O 2 coordination geometry. Complex Cu(l-pro)(bpy)(H 2O)(NO 3) (1) crystallizes in the triclinic space group P1 with unit cell parameters: a = 7.082(3) à , b = 10.483(5) à , c = 11.581(5) à , α = 89.700(7)°, β = 83.488(8)°, γ = 84.109(8)° and V = 849.7(7) à 3. The one-electron paramagnetic complexes display a d-d band near 600 nm in water and show a cyclic voltammetric response due to Cu(II)/Cu(I) couple near 0.1 V (versus SCE) in Tris-HCl buffer-0.1 M KCl. Binding interactions of the complexes with calf thymus (CT) DNA have been investigated by emission, absorption, viscosity and DNA thermal denaturation studies. The phen complex displays significant binding propensity to the CT DNA giving an order: 2 (phen) â 1 (bpy). The bpy complex does not show any apparent binding to the DNA and hence poor cleavage efficiency. Complex 2 shows efficient oxidative cleavage of SC-DNA in the presence of 3-mercaptopropionic acid (MPA) involving hydroxyl radical species as evidenced from the control data showing inhibition of DNA cleavage in the presence of DMSO and catalase. © 2007 Elsevier Ltd. All rights reserved

Reserve Estimation of Proposed Opencast Mine of Ramnagore Colliery

As jhama and burnt coal are saleable items with sizeable demand in different small and medium scale industries, the management of Ramnagore Colliery of Steel Authority of India Ltd. (SAIL) has decided to mine jhama, burnt coal, coal and the strata of jhama intruded by mica peridotite from Salanpur D-2, Salanpur D-1 and Salanpur C seams in a block near north-eastern boundary of the colliery, covering a total area of around 22.01 hectare. The proposed mine is located in Ramnagore part of Indikatta-Ramnagore Block on the eastern bank of the Barakar River in Raniganj Coalfield. This paper describes the methodology of reserve estimation along with estimation of pit life, waste and stripping ratio. Geological report by Central Mine Planning & Design Institute Ltd. (CMPDI) in 1995 forms the basis of the geological information of the area. The report indicates that due to pyrolysis, the seams have been transformed into a combination of layers of jhama, burnt coal, coal and the layers of jhama intruded by mica peridotite. Of the 15 boreholes in and around the proposed opencast mining site, lithologs of only 13 boreholes are available with the mine management and only 8 boreholes fall inside the proposed mining area. The classification of seams in the lithology of the boreholes is neither very clear, nor very convincing. The results indicate that it would be much more economic to mine the site en bloc than to mine Western and Eastern blocks separately leaving a 90 m wide barrier in between them to protect the existing high voltage electric supply line. In isolation, the West Block, which covers nearly two-third of the whole site, will run for two-and-half years, producing a little more than 40% of the total mineable reserve of the whole site and generating 63% of the total waste likely to be generated had the whole site been mined as one. Overall stripping ratio of the Western Block will be 8.36 M3/t, i.e. nearly one and half times of the stripping ratio of 5.47 M3/t, expected for the mining of the whole site in one go. The Eastern block that covers only about 15% of the whole site will result in production for only two months. The production will comprise not even 3% of the total mineable reserve in the whole site, that too with a high oveall stripping ratio of 12.82 M3/t. On the other hand, if the whole site is mined en bloc, the mine is likely to run for six years yielding more than 0.7 million tonne of minerals (coal, burnt coal and jhama together) with a stripping ratio of 5.47 M3/t approximately

Disaster due to coal Mines Explosions

This paper deals with an account of occurrences and causes behind disaster due to explosions in Indian mines. Principal causes and mechanism s of explosion, and precautions against explosion are also discussed. The review indicated that although frequency of occurrence of explosion inducted disasters have reduced over the years in coal mines of India, there is a need of implementation of modern technologies such as environmental tele-monitoring system in fire prone mines in general, and in degree II/III gassy mines in particular, to arrive at the zero-disaster regime. There is a need for an additional categorization of gassiness of seam such as degree IV gassy seam for the seam where rate of gas emission is more than m3 per tonne of coal raised. Arrangement for methane drainage or coal seam degasification or cal bed methane recovery should be given top priority on degree III and proposed degree IV mine

New ternary copper(II) complexes of l-alanine and heterocyclic bases: DNA binding and oxidative DNA cleavage activity

Four new ternary copper(II) complexes of α-amino acid having polypyridyl bases of general formulation [Cu(l-ala)(B)(H2O)](X) (1–4), where l-ala is l-alanine, B is an N,N-donor heterocyclic base, viz. 2,2′-bipyridine (bpy, 1), 1,10-phenanthroline (phen, 2) and 5,6-phenanthroline dione (dione, 3), dipyrido[3,2:2′,3′-f]quinoxaline (dpq, 4), and X = View the MathML source/View the MathML source are synthesized, characterized by various spectroscopic and X-ray crystallographic methods. The complexes show a distorted square-pyramidal (4 + 1) CuN3O2 coordination geometry. The one-electron paramagnetic complexes (1–4) display a low energy d–d band near 600 nm in aqueous medium and show a quasi-reversible cyclic voltammetric response due to one-electron Cu(II)/Cu(I) reduction near −100 mV (versus SCE) in DMF–0.1 M TBAP. Binding interactions of the complexes with calf thymus DNA (CT-DNA) were investigated by UV–Vis absorption titration, ethidium bromide displacement assay, viscometric titration experiment and DNA melting studies. All the complexes barring the complexes 1 and 3 are avid binder to the CT-DNA in the DNA minor groove giving an order: 4 > 2 ⋙ 1, 3. The complexes 2 and 4 show appreciable chemical nuclease activity in the presence of 3-mercaptopropionic acid (MPA) as a reducing agent. Hydroxyl radical was investigated to be the DNA cleavage active species. Control experiments in the presence of distamycin-A show primarily minor groove-binding propensity for the complexes 2 and 4 to the DNA

Clean coal technology to improve environmental qualtiy and energy efficiency

Coal is the world’s most abundant and widely distributed fossil fuel source. It is a major source of commercial energy in the present scenario. Coal currently supplies over one third of the world’s electricity and 23% of global primary energy needs. Conventional power generation system, though one of the cheapest means of production of electricity in the world, have energy efficiency only 30-35%. However, it has enormous environmental impact which includes emission of large amount of gases like CO2, SO2, NOx, and Hg, particulate matter which primarily includes fly ash. This is responsible for global warming and air and water pollution. To reduce this environmental impact due to emissions from thermal power plant and to meet the quality requirements of the coal consumers, it is imperative to adopt clean coal technologies. “Clean coal” is a term used in the promotion of the use of coal as an energy source by emphasizing methods being developed to reduce its environmental impact. This paper addresses advanced power generation systems like integrated gasification combined cycle (IGCC) system and underground coal gasification (UCG) which claim to have energy efficiency in the rage of 45-50%. Carbon capture and storage (CCS) technology for capturing emitted CO2 and storing it in geological formation appears to be one of the efficient means to reduce CO2 in the atmosphere. This technology has also been enumerated in this paper. An account for global and Indian initiatives for clean coal technology is given. Clean coal mining operation along with coal preparation technology practiced in India is also discussed in brief

Effect of super-optimal levels of fertilizers on soil enzymatic activities during growth stages of wheat crop on an Inceptisol

A field experiment was conducted during 2010-2011 and 2011-2012 to investigate the effect of optimal (100% NPK) to super-optimal doses (200% NPK) of mineral fertilizers on soil enzymes such as dehydrogenase (DHA), acid phosphatase (Ac-PA), alkaline phosphatase (Alk-PA), fluorescien diacetate hydrolysis (FDA), urease and nitrate reductase (NRA) at three physiological stages (CRI, anthesis and maturity) of wheat crop on an Inceptisol. Dehydrogenase activity was reduced by 28-37% when fertilizer application was at super-optimal dose (200% NPK), whereas, urease and NRA responded positively in the range of 43-44% and 213-231% respectively. Alk-PAwas 7.3-7.9% higher in treatments receiving 125% NPK as compared to control (100% NPK); whereas, Ac-PA declines in the plots receiving 175 and 200% of recommended dose of fertilizer (RDF) as compared to 150% NPK levels. Addition of 175% RDF increased the FDA to the tune of 46-53% as compared to 100% NPK. A significant (P?0.05) positive interaction between fertilizer treatments and physiological stages of wheat growth was observed on soil enzyme activities (except urease and NRA) being highest at the anthesis stage of wheat. Correlation matrix analysis showed that DHA was correlated with the studied enzyme activities except Ac-PA and FDA; whereas, strong correlation was observed between urease and NRA (r=0.981, P=0.01). This study provides theoretical and practical base for avoiding super optimal application of fertilisers which hinders the enzyme activities and vis-a-vis sustainable nutrient enrichment under rhizosphere

Cytomorphological Studies on Stem of Luffa echinata Roxb

Luffa echinata Roxb., commonly known as Bindal in Hindi is used for its hypoglycemic activity in the indigenous system of medicine. No pharmacognostical study on stem is reported in the literature till date; therefore, it was decided to study macroscopical and cytomorphological characters in detail to bring out salient diagnostic features. The stem pieces available in the market are 1.5–17 cm long and 5–8 mm in diameter, showing yellowish-brown to brownish-black surface with longitudinal furrows, fracture is fibrous, and taste is bitter. Mature stem shows single-layered epidermis, seven layers of collenchyma below five ridges but one to two layers of parenchyma in rest of the region beneath the epidermis, continuous wide wavy layer of pericycle composed of three to eight layers of fiber. There are five conjoint bi-collateral open vascular bundles one below each ridge and additional four medullary vascular bundles in the pith each facing furrows

Effects of Bt-cotton on biological properties of Vertisols in central India

Growing areas under transgenic crops have created a concern over their possible adverse impact on the soil ecosystem. This study evaluated the effect of Bt-cotton based cropping systems on soil microbial and biochemical activities and their functional relationships with active soil carbon pools in Vertisols of central India (Nagpur, Maharastra, during 2012–2013). Culturable groups of soil microflora, enzymatic activities and active pools of soil carbon were measured under different Bt-cotton based cropping systems (e.g. cotton-soybean, cotton-redgram, cotton-wheat, cotton-vegetables and cotton-fallow). Significantly higher counts of soil heterotrophs (5.7–7.9 log cfu g−1soil), aerobic N-fixer (3.9–5.4 log cfu g−1soil) and P-solubilizer (2.5−3.0 log cfu g−1soil) were recorded in Bt-cotton soils. Similarly, soil enzymatic activities, viz. dehydrogenase (16.6–22.67 µg TPF g−1 h−1), alkaline phosphatase (240–253 µg PNP g−1 h−1) and fluorescein di-acetate hydrolysis (14.6–18.0 µg fluorescein g−1 h−1), were significantly higher under Bt-cotton-soybean system than other Bt- and non-Bt-cotton based systems in all crop growth stages. The growth stage-wise order of soil microbiological activities were: boll development > harvest > vegetative stage. Significant correlations were observed between microbiological activities and active carbon pools in the rhizosphere soil. The findings indicated no adverse effect of Bt-cotton on soil biological properties