12 research outputs found
Various Aspects of Bollard Pull Tests and Analysis of Test Results
No full textThe static force exerted on a hawser at zero ship speed by a vessel, otherwise known as the bollard pull, is one of the key performance indicators of Tugs, Anchor Handling Tugs (AHTs) and Anchor Handling Tug Supply Vessels (AHTSVs). The value of bollard pull is considered critical as it defines the functionality and performance of the vessel. When a company decides on chartering a vessel, a definite prerequisite considered is the value of the bollard pull. The value may be obtained via three ways: calculations, model-testing, and full-scale trials. The latter is often used officially to certify the vessel's bollard pull rating, with the presence of the vessel's owners, surveyors, and any other third parties. The tests and trials follow a set of guidelines provided by classification societies but do not have a standardized set of rules. Therefore, disagreements often arise over the results of such tests and trials. Tests are often carried without any load cells measuring the shaft power to ascertain the brake horsepower (BHP). Simply, engine rpm/ rating is used to fix the 100% maximum continuous rating (MCR) which often in the range of 105–108% MCR. Some of the parties involved in certifying the correct bollard pull tests (BPTs) do not even understand what is all about the bollard pull. Everybody is looking for a higher figure for the bollard pull on the certificate when the reality is different. The author examines and discusses the broad spectrum of factors that affects the "true" value of the bollard pull and explains why such a standardized set of mandatory BPT and the trial code is deemed necessary. The author also presents some of the interesting BPTs data to show the differences in various ways of conducting BPTs.
1. Introduction
The bollard pull (BP) is the zero speed pulling/pushing capability of a vessel, i.e., Tugs, Anchor Handling Tug (AHTs), Anchor Handling Tug/ Towing Supply Vessel (AHTSVs), trawlers, etc. It is considered as one of the key practical performance indicators of the above-mentioned vessels, measuring the usefulness of the vessel in a stranding scenario or in holding large vessels such as tankers or towing a rig.
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Portable mini-chamber for temperature dependent studies using small angle and wide angle x-ray scattering
No full textThe present work describes the design and performance of a vacuum compatible portable mini chamber for temperature dependent GISAXS and GIWAXS studies of thin films and multilayer structures. The water cooled body of the chamber allows sample annealing up to 900 K using ultra high vacuum compatible (UHV) pyrolytic boron nitride heater, thus making it possible to study the temperature dependent evolution of structure and morphology of two-dimensional nanostructured materials. Due to its light weight and small size, the chamber is portable and can be accommodated at synchrotron facilities worldwide. A systematic illustration of the versatility of the chamber has been demonstrated at beamline P03, PETRA-III, DESY, Hamburg, Germany. Temperature dependent grazing incidence small angle x-ray scattering (GISAXS) and grazing incidence wide angle x-ray scattering (GIWAXS) measurements were performed on oblique angle deposited Co/Ag multilayer structure, which jointly revealed that the surface diffusion in Co columns in Co/Ag multilayer enhances by increasing temperature from RT to ∼573 K. This results in a morphology change from columnar tilted structure to densely packed morphological isotropic multilayer</p
Metagenomic Exploration of Microbial Signatures on Periyar River Sediments from the Periyar Tiger Reserve in the Western Ghats
No full textABSTRACT
We report here targeted deep-sequencing metagenomic data that reveal a high level of diversity in the microbiota residing in the sediment of the Periyar River in a reserve forest of the Western Ghats. Of the 4,674 operational taxonomic units discovered, the dominant phyla represented were
Proteobacteria
(33.12%),
Actinobacteria
(14.58%),
Acidobacteria
(12.81%), and
Bacteroidetes
(9.89%).
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Gymnostachyum warrieranum (Acanthaceae), a new species from the Western Ghats of India, based on morphological and molecular data
No full textExploring prevalence of potential pathogens and fecal indicators in geographically distinct river systems through comparative metagenomics
No full textDe novo genome assembly of Tectona grandis (Teak) with 2993 scaffolds
No full textTeak (Tectona grandis L. f.) is one of the precious bench mark tropical hardwood having qualities of durability, strength and visual pleasantries. Natural teak populations harbour a variety of characteristics that determine their economic, ecological and environmental importance. Sequencing of whole nuclear genome of teak provides a platform for functional analyses and development of genomic tools in applied tree improvement. A draft genome of 317 Mb was assembled at 151× coverage and annotated 36, 172 protein-coding genes. Approximately about 11.18% of the genome was repetitive. Microsatellites or simple sequence repeats (SSRs) are undoubtedly the most informative markers in genotyping, genetics and applied breeding applications. We generated 182,712 SSRs at the whole genome level, of which, 170,574 perfect SSRs were found; 16,252 perfect SSRs showed in silico polymorphisms across six genotypes suggesting their promising use in genetic conservation and tree improvement programmes. Genomic SSR markers developed in this study have high potential in advancing conservation and management of teak genetic resources. Phylogenetic studies confirmed the taxonomic position of the genus Tectona within the family Lamiaceae. Interestingly, estimation of divergence time inferred that the Miocene origin of the Tectona genus to be around 21.4508 million years ago.Funding provided by: Department of Biotechnology, Government of IndiaCrossref Funder Registry ID: http://dx.doi.org/10.13039/501100001502Award Number: BT/PR7143/PBD/16/1011/2012WGS was performed using Illumina HiSeq 2000 platform and Oxford Nanopore Technologies MinION device by the Genotypic Technology, Bengaluru, India in accordance to standard protocols. Accession 2 was selected for the generation of high quality reference genome assembly. Accessions 1, 3, 4, 5 and 6 were subjected to low coverage genome sequencing to identify polymorphic SSRs. In the case of accession 2, one paired end (PE) (150 bp × 2) library of size 300–700 bp, two mate pair (MP) libraries (2–4 and 4–6 kb fragments) and one nanopore library with genomic DNA (2 μg) were prepared for sequencing. In Illumina HiSeq 2000 platform, one lane of the flow cell was used for each sequencing library. Nanopore sequencing was performed using R9.4 flow cells on a MinION Mk 1B device (Oxford Nanopore) with the MinKNOW software (versions 1.0.5–1.5.12) and base calling was performed using Albacore 1.1.0 (Oxford Nanopore). Template reads were exported as FASTA using poretools version 0.6. In the case of other five accessions (1, 3, 4, 5 and 6) one PE library for each with the size of 300–700 bp was sequenced at ∼15× coverage through Illumina Hiseq 2000 platform. The raw data is uploaded in genome database of GenBank (Project id: PRJNA374940).
The Illumina PE raw reads were filtered using FastQC and the raw reads were processed by in-house (Genotypic Technology, Bangaluru, India) ABLT script for low-quality bases and adapters removal. The MP reads were processed using Platanus24 internal trimmer for adapters and low-quality regions towards 3'-end. The processed PE reads along with MP and nanopore reads were used for contig generation using MaSuRCA v 3.2.2 de novo assembler.25 To assemble the genome following command was used in MaSuRCA assembler: GRAPH_KMER_SIZE = auto, LIMIT_JUMP_COVERAGE = 300, JF_SIZE = 38000000000, DO_HOMOPOLYMER_TRIM = 1. Scaffolding of the assembled contigs was performed using SSPACE v 2.0.526 with processed PE and MP reads followed by gap filling using Gap Closer v 1.12.27 The genome size was estimated automatically during read computing stage which utilized both the Illuimna and Nanopore reads. Similarly, the low depth Illumina reads generated for five accessions of teak were assembled using accession 2 as reference. The sequenced data was uploaded to the Genome database of GenBank (Project id: PRJNA421422).
For a functional overview of draft genome, assembled scaffolds were converted to FASTA formatted sequences, hard masked by RepeatMasker tool (RepeatMasker Open-3.0; www.repeatmasker.org (10 November 2017, date last accessed)). Repeats of Arabidopsis thaliana were used as reference for genome masking. Gene prediction was carried out using Augustus 3.0.228 programme and predicted proteins were searched against the Uniprot non-redundant plant protein database (Taxonomy = Viridiplante) with BlastX algorithm with an e-value (e-10) for gene ontology and annotation. Pathway annotation was performed by mapping the sequences obtained from Blast2GO to the contents of the KEGG Automatic Annotation Server (http://www.genome.jp/kegg/kaas/ (10 November 2017, date last accessed)
Draft genome of a high value tropical timber tree, Teak (Tectona grandis L. f): insights into SSR diversity, phylogeny and conservation
No full textDNA Glycosylases Involved in Base Excision Repair May Be Associated with Cancer Risk in BRCA1 and BRCA2 Mutation Carriers.
No full textSingle Nucleotide Polymorphisms (SNPs) in genes involved in the DNA Base Excision Repair (BER) pathway could be
associated with cancer risk in carriers of mutations in the high-penetrance susceptibility genes BRCA1 and BRCA2, given the relation of synthetic lethality that exists between one of the components of the BER pathway, PARP1 (poly ADP ribose
polymerase), and both BRCA1 and BRCA2. In the present study, we have performed a comprehensive analysis of 18 genes involved in BER using a tagging SNP approach in a large series of BRCA1 and BRCA2 mutation carriers. 144 SNPs were analyzed in a two stage study involving 23,463 carriers from the CIMBA consortium (the Consortium of Investigators of Modifiers of BRCA1 and BRCA2). Eleven SNPs showed evidence of association with breast and/or ovarian cancer at p,0.05 in the combined analysis. Four of the five genes for which strongest evidence of association was observed were DNA glycosylases. The strongest evidence was for rs1466785 in the NEIL2 (endonuclease VIII-like 2) gene (HR: 1.09, 95% CI (1.03– 1.16), p = 2.761023) for association with breast cancer risk in BRCA2 mutation carriers, and rs2304277 in the OGG1 (8-guanine DNA glycosylase) gene, with ovarian cancer risk in BRCA1 mutation carriers (HR: 1.12 95%CI: 1.03–1.21,
p = 4.861023). DNA glycosylases involved in the first steps of the BER pathway may be associated with cancer risk in BRCA1/ 2 mutation carriers and should be more comprehensively studied
