Some Remarks on Ricci Solitons

We obtain an intrinsic formula of a Ricci soliton vector field and a differential condition for the non-steady case to be gradient. Next we provide a condition for a Ricci soliton on a Kaehler manifold to be a Kaehler–Ricci soliton. Finally we give an example supporting the first result

Fast 3D Integrated Circuit Placement Methodology using Merging Technique

In the recent years the advancement in the field of microelectronics integrated circuit (IC) design technologies proved to be a boon for design and development of various advanced systems in-terms of its reduction in form factor, low power, high speed and with increased capacity to incorporate more designs. These systems provide phenomenal advantage for armoured fighting vehicle (AFV) design to develop miniaturised low power, high performance sub-systems. One such emerging high-end technology to be used to develop systems with high capabilities for AFVs is discussed in this paper. Three dimensional IC design is one of the emerging field used to develop high density heterogeneous systems in a reduced form factor. A novel grouping based partitioning and merge based placement (GPMP) methodology for 3D ICs to reduce through silicon vias (TSVs) count and placement time is proposed. Unlike state-of-the-art techniques, the proposed methodology does not suffer from initial overlap of cells during intra-layer placement which reduces the placement time. Connectivity based grouping and partitioning ensures less number of TSVs and merge based placement further reduces intra layer wire-length. The proposed GPMP methodology has been extensively against the IBMPLACE database and performance has been compared with the latest techniques resulting in 12 per cent improvement in wire-length, 13 per cent reduction in TSV and 1.1x improvement in placement time

Analysis of interaction between Arbuscular Mycorrhizal fungi and their Helper bacteria by MILPA model

Many recent researches carried out the research in mycorrhizal symbiosis to improve crop growth in the agriculture but they differ in their approaches like crops and the agricultural perspectives. The study focused on the interaction of Arbuscular mycorrhizal (AM) fungi and helper bacteria, influence maize growth through milpa as a model system to analyze soil enzyme activity of acid, alkaline phosphatase and signaling molecule of phospholipids fatty acid (PLFA) profile. Bioinoculants plays an important role in plant growth like nutrient mobilization, biocontrol and prevent the plants from stress. The maize crops were treated with bio inoculants such as Azospirillum, Azotobacter, Rhizobium,Pseudomonas and AM fungi. Significant diverse effects were observed with bioinoculants in the crops compared to control crop. The number spores formed was proportional to the rate of colonization.AM fungi association in plant roots helps the plants in nutrient uptake especially phosphorus (P) from soil materials. The enzyme activities were also found to influence the growth of the plant and phospholipids fatty acid (PLFA) profile influences the interaction between bacterium and AMF. Plant and phospholipids fatty acid analysis is asensitive and accurate method in determining microbial community structures, because it depends on living cell contents of microorganisms under in situ conditions. It confirmed with gas chromatographic analysis of PLFA to determination of the structure and total biomass of microbial community in treated soil samples

Measurements of peripheral dose for multileaf collimator based linear accelerator

BackgroundIn radiation therapy, peripheral dose (PD), or the dose outside the geometrical boundaries of the radiation field, is of clinical importance when anatomical structures such as foetus in pregnant women, gonads, and lenses of the eye, with low dose tolerances are involved. Even a small percentage of the total treatment dose might cause injury in such cases. The sources of peripheral dose are leakage from the treatment unit, scatter from the secondary collimators and beam modifiers such as wedges and blocks, and internal scatter originating in the patient.AimTo determine the peripheral dose (PD) for multileaf collimator (MLC) based linear accelerator in water equivalent slab phantom for open and wedged fields.Materials/MethodsPD measurements were carried out for 6 and 15 MV photons using a 0.4cc parallel plate chamber in the slab phantom. Measurements were performed for different field sizes at different depths (Dmax, 5 cm and 10 cm) and up to a maximum distance of 30 cm beyond the field edges. PD was measured using wedge filters also. PD was further computed using a three-dimensional treatment planning system (3D TPS).ResultsFor 6 MV photon beams, the maximum PD for open beams at 5 cm distance from the field edge was 3.42% and the minimum PD at 20 cm distance was 0.11%. For 15 MV, the maximum PD for open beam at 5 cm distance was 3.07% and the minimum PD was 0.14%. For wedge filters, the maximum PD measured at 5 cm distance for 6 and 15 MV photons were 5.56% (60° Wedge) and 5.03% (45° wedge). The TPS PD values showed minimal variation from the measured values.ConclusionsThe PD due to MLC and beam modifiers would definitely be helpful to assess the doses received by the relevant critical structures outside the treatment field

Studies on Distribution of Biosurfactant Producing Bacteria in Contaminated and Undisturbed Soils of Kanchipuram

Abstract: Ever increasing environmental concern about chemical surfactants triggers attention to microbial derived surface-active compounds, essentially due to their low toxicity and biodegradable nature. At present, biosurfactants are predominantly used in remediation of pollutants, in the enhanced transport of metabolites in bacteria, in enhanced oil recovery, as cosmetic additives, in biological control. However, little is known about the distribution and prevalence of biosurfactant-producing bacteria in the environment. The primary objective of this study was to determine how common culturable surfactant producing bacteria are present in contaminated and undisturbed soil samples in and around Kanchipuram (12°50'23"N 79°42'0"E), Tamilnadu, India. A series of each 5 contaminated and undisturbed soils were collected and plated on R2A agar. Totally, 155 morphologically different bacterial isolates were obtained and qualitatively screened for biosurfactant production in mineral salts medium containing 2% glucose. Out of 155 isolates, eight isolates were positive for biosurfactant production, representing most of the soils tested. Quantitative estimation of surface activity identified two potent biosurfactant producing strains Bacillus sp.BS3 and Pseudomonas sp. Maximum surface activity was observed to be 26.58 x 10 -3 nm -1 and 20.60 x 10 -3 nm -1 respectively for Bacillus sp.BS3 and Pseudomonas sp. BS5. The present study is a preliminary demonstration that the Indian soils are rich in biosurfactant producing bacteria, which can be exploited for industrial production of biosurfactants

Activation of the Connective Tissue Growth Factor (CTGF)-Transforming Growth Factor β 1 (TGF-β 1) Axis in Hepatitis C Virus-Expressing Hepatocytes

Background: The pro-fibrogenic cytokine connective tissue growth factor (CTGF) plays an important role in the development and progression of fibrosis in many organ systems, including liver. However, its role in the pathogenesis of hepatitis C virus (HCV)-induced liver fibrosis remains unclear. Methods: In the present study, we assessed CTGF expression in HCV-infected hepatocytes using replicon cells containing full-length HCV genotype 1 and the infectious HCV clone JFH1 (HCV genotype 2) by real-time PCR, Western blot analysis and confocal microscopy. We evaluated transforming growth factor β1 (TGF-β1) as a key upstream mediator of CTGF production using neutralizing antibodies and shRNAs. We also determined the signaling molecules involved in CTGF production using various immunological techniques. Results: We demonstrated an enhanced expression of CTGF in two independent models of HCV infection. We also demonstrated that HCV induced CTGF expression in a TGF-β1-dependent manner. Further dissection of the molecular mechanisms revealed that CTGF production was mediated through sequential activation of MAPkinase and Smad-dependent pathways. Finally, to determine whether CTGF regulates fibrosis, we showed that shRNA-mediated knock-down of CTGF resulted in reduced expression of fibrotic markers in HCV replicon cells. Conclusion: Our studies demonstrate a central role for CTGF expression in HCV-induced liver fibrosis and highlight the potential value of developing CTGF-based anti-fibrotic therapies to counter HCV-induced liver damage