Rational finite difference approximation of high order accuracy for nonlinear two point boundary value problems

In this paper, we present a new method for solving nonlinear general two point boundary value problems. A method based on finite differences and rational function approximation and we call this method as rational approximation method. A rational approximation method is applied to construct the numerical solution for two point boundary value problems. The novel method is tested on three model problems. Thus the numerical results obtained for these model problems show the performance and efficiency of the developed method

Nitrogen-fixing aerobic bacteria and their nitrogenase activity in north Mumbai coastal waters

The effect of the physicochemical parameters of water and soil on the distribution of nitrogen-fixing bacteria and their nitrogen-fixing capacity was studied. Four species of nitrogen-fixing bacteria, e. g. Azotobacter chroococcum, A. vinelandii, A. beijerinckii and A. armeniacus, were recorded from water and soil samples of Mumbai coast. A higher number of bacterial populations were observed in sediment than in water samples. A positive correlation was observed between the dissolved organic matter and nitrogen fixing bacterial populations of water as well as between available phosphorus and the nitrogen-fixing bacteria of sediment. The nitrogen-fixing capacity of A. chroococcum was found to be 1.076 nmol C sub(2) H sub(4)/l/d and that of A. vinelandii was 0.965 nmol C sub(2) H sub(4)/l/d. Station 1 showed higher level of nitrogenase activity in comparison to other four stations

A Class of Pseudo-Differential Operators Associated with Bessel Operators

AbstractA class of pseudo-differential operators (p.d.o.), generalizing Bessel differential operator d2/dx2 + (1 − 4μ2)/(4x2), is defined. Symbol classes Hm and Hm0 are introduced. It is shown that p.d.o.′s associated with symbols belonging to these classes are continuous linear mappings of the Zemanian space Hμ into itself. An integral representation of p.d.o.′s is obtained. Using Haimo′s theory of the Hankel convolution it is shown that p.d.o.′s satisfy a certain L1 - norm inequality

Effects of probiotics and antibiotics on biofilms

Experiments were conducted to study the effects of probiotics and antibiotics on 3-months old biofilms formed on three different substrates, namely glass, granite and fiberglass reinforced plastic. The variations in heterotrophic bacterial populations associated with biofilms were monitored for a period of one month after one-time application of the probiotic Biogreen (Gee Key Marine Pvt. Ltd, Chennai) at 0.2 mg lˉ¹ and the antibiotic tetracycline at 1.0 mg lˉ¹. The variations in heterotrophic bacterial populations associated with biofilms were compared with that of control to analyse the effects of probiotics and antibiotics on biofilms. The observations showed that the biofilm formation and succession in aquatic environment is substrate dependent and that the resistance to antibiotics also depends on the substrate. The probiotics did not show significant effect on biofilms

Effect of combined thyroxine and cortisol treatment on hatching of eggs, post-embryonic growth and survival of larvae of Heteropneustes fossilis

In order to record the effects of thyroxine and cortisol (individual/combined) on hatching, post-embryonic growth and survival of larvae of Heteropneustes fossilis, newly fertilized eggs were given bath immersion treatments of L-thyroxine (T sub(4); 0.05 mg/l), cortisol (0.50 mg/l) and T sub(4)+ cortisol (0.05 mg/l+0.50 mg/l) for 15 days. Hatching of eggs, growth and survival of the larvae improved significantly (P<0.001) in the hormone treated groups as compared to those of control. The frequency of deformities was reduced in the combined hormone treatment group. The present observations suggest that the advanced digestive function probably induced by T sub(4)+cortisol treatment might have resulted in improvement in food utilization during the critical phases of first feeding and promoted vital developmental processes resulting in uniform growth, decreased mortality, better survival and transformation of larvae to juveniles. This combined hormone therapy appears to have practical utility in fish hatchery practice for better success in larval rearing

Fisheries profile mapping of coastal districts in Maharashtra state through GIS

In recent times, GIS is being increasingly used as a decision support system for management of fisheries and aquaculture. It provides new innovative approaches of the dynamic relations that characterize this sector. In this context, a study is conducted based on the secondary data of a major maritime state, Maharashtra, where mapping of fisheries profile of coastal districts in the state is performed through GIS tool having critical geographic dimensions. This paper aims to map information of the state which can be used for the purpose of planning and decision making as each aspect of map has a different component involved. For this purpose, at the core of the system, the data were accessed and integrated from different sources mainly from the five coastal districts of Maharashtra state. Data were brought in tabular form through Microsoft Excel and then joined to Map info Professional version 8.0 GIS software was used with the digitized map of Maharashtra state to enable mapping. This was further synchronized and integrated to generate four thematic maps searchable on several criteria. Map 1 contains the searchable criteria as regards to the fish growth for the year 1997-2004 and fish seed production for the year 2003-04. Map 2 contains fisher population along with their occupation for the year 1992. Map 3 contains brackish water and shrimp farming production and culture area. Map 4 contains infrastructural facilities which include type of boats etc. With this mapping, planners and various stakeholders have accessible information as regards to the various components of fisheries in the state of Maharashtra

Dielectric Properties of Nanostructured PZTSynthesised by Chemical Methods

In this study, the dielectric behaviour of smart material, lead zirconate tiatanate (PZT), whichis important for wide industrial applications, has been explored. Two samples of nanostructuredPb(Zr0.52Ti0.48)O3 ceramic powders were prepared by hydroxide co-precipitation and aqueoussolution method (water bath technique). The XRD pattern of the  powder exhibited the presenceof major tetragonal and minor rhombohedral crystalline phases indicating the mixed-phasecomposition, which is close to the morphotropic phase boundary (MPB). SEM analysis revealedgood homogeneity of the materials. The plot of real part versus imaginary part of the compleximpedance was observed nearly a semicircle, indicating that the samples are good dielectricmaterials, whose resistance decreases considerably with the increase of temperature. Similar tothe normal ferroelectric materials, the dielectric constant () of PZT has been found to be increasinggradually with temperature and attains a maxima (max). The detailed analysis for the shift in peaktemperature and dielectric constant were carried out

A rare case of leiomyosarcoma of cervix and challenges in its management: a case report and brief review of literature

Leiomyosarcoma of cervix is an aggressive and rare tumour of the cervix with poor prognosis. Management plan differs greatly from other common cervical malignancies. A 38 year old multiparous lady presented with a large circumferential cervical tumour which was diagnosed as leiomyosarcoma of cervix on cervical biopsy. It was a surgical challenge. Patient underwent pre-operative ureteric stenting followed by exploratory laparotomy with hysterectomy with bilateral salphingo-oophorectomy. Surgical difficulties were encountered due to deep impaction of tumour in pelvis and altered anatomy due to the bulk of tumour. Retrograde approach was taken and pouch of Douglas was opened before clamping the mackenrodts and the uterus was bisected and debulking of tumour done simultaneously to facilitate the surgery. Post operatively patient received chemotherapy (Vincristine, adriamycin andcyclophosphamide) followed by radiotherapy. Patient developed vesicovaginal fistula and liver metastasis nine months post- surgery. She received second line of chemotherapy (gemcitabine and docetaxel) after which she was lost to follow up.

Growth and Hemato-Immunological Response to Dietary i-Carrageenan in Labeo rohita (Hamilton, 1822) Juveniles

The study was performed over a period of 60 days to evaluate the effect of dietary carrageenan on growth, hematology, biochemistry, and innate immunity in rohu Labeo rohita. A basal diet supplemented with iota (i)Carrageenan at 5, 10 and 20g/kg was fed to three different groups of fish for 60 days. The fish were examined 15, 30, 45, and 60 days after commencement of the study. Parameters for growth (absolute growth, specific growth rate, and percentage weight gain), hematology (total erythrocyte count, total leucocyte count, thrombocyte count and hemoglobin value), biochemistry (total serum protein, albumin, globulin and albuminglobulin ratio), and innate immunity (nitroblue tetrazolium NBT, and myeloperoxidase MPO, activity) were monitored to assess the effect of the iCarrageenan based diet in L. rohita. All the parameters examined (growth, hematology, biochemistry, and innate immunity) increased significantly (P<0.05) in carrageenan-fed groups compared to the control group. However, the highest values for those parameters were found on the 60th day in the group which was fed a 10 g/kg i-Carrageenan diet. The study suggests that a 10 g/kg diet of i-carrageenan enhances immunity and the overall health status in L. rohita