Production of export quality agar

The seaweeds are the renewable and economically valuable wealth of the sea. The phytochemicals agar and algin are produced from the seaweeds. The red algae Gelidiella. acerosa and Gracilaria edulis are the source of raw materials for agar industries and Sargassum and Turbinaria for algin industries. Annually 50 tons of agar and 500 tons of alginates are manufactured in India

Photosynthetic pigment of marine algae from Mandapam coast

Thirty species of marine algae collected from different localities of Mandapam coast (Gulf of Mannar) were analyse!! for their photosynthetic pigments suct. as chlorophyll and carotenoids. The lowest value. of chlorophyll as well as carotenoids content were found in Rhodophyceae. The grouping and separation of algae based on coloration has been practiced for over 100 years (Harvey, 1841). Pigments such as chlorophyll and carotenoids play important roles in photosynthesis. Several studies have been conducted in the algal pigment by Ramus el al. (1976); Brody el al. (1959); Jones el at. (1965) and Waaland el al. (1974). As there is no detailed work in this line on India.l seaweeds, the present study.of thirty species of marine algae belonging to Chlorophyta, Phaeophyta and Rhodophyta from Mandapam coast has been carried out

Microelectromechnical Systems Inertial Measurement Unit Error Modelling and Error Analysis for Low-cost Strapdown Inertial Navigation System

This paper presents error modelling and error analysis of microelectromechnical systems (MEMS) inertial measurement unit (IMU) for a low-cost strapdown inertial navigation system (INS). The INS consists of IMU and navigation processor. The IMU provides acceleration and angular rate of the vehicle in all the three axes. In this paper, errors that affect the MEMS IMU, which is of low cost and less volume, are stochastically modelled and analysed using Allan variance. Wavelet decomposition has been introduced to remove the high frequency noise that affects the sensors to obtain the original values of angular rates and accelerations with less noise. This increases the accuracy of the strapdown INS. The results show the effect of errors in the output of sensors, easy interpretation of random errors by Allan variance, the increase in the accuracy when wavelet decomposition is used for denoising inertial sensor raw data.Defence Science Journal, 2009, 59(6), pp.650-658, DOI:http://dx.doi.org/10.14429/dsj.59.157

Simple sequence repeat (SSR) markers for assessing genetic diversity among the parental lines of hybrid rice (Oryza sativa L.)

The present scientific study was carried out at Tamil Nadu Rice Research Institute, Aduthurai with the objective of studying the genetic divergence among 51 restorer and five maintainer lines in terms of grain quality and fertility restorer genes (Rf3, Rf4 and Rf7) using 55 primers of simple sequence repeat (SSR) markers. Among them, 37 SSR markers were found to be polymorphic and the number of amplified fragments ranged from one to five. The highest polymorphic information content (PIC) value (more than 0.60) was observed for eight primers viz., AB 443, RM 3, RM 29, RM 226, RM 228, RM 304, RM 1812 and RM 3873 and average PIC value was 0.444. Cluster analysis using NTSYS generated dendrogram divided all the 56 parental lines into two distinct groups viz., maintainer line (Group I) and restorer line (Group II) at 76% coefficient of similarity. Maintainer line group consisted of five genotypes (COMS 23B, COMS 24B, COMS 25B, CRMS 31B and CRMS 32B) and restorer line group had 51 genotypes. Further, at 80% similarity, all fifty one restorer lines were again grouped into nine clusters. With higher polymorphism revealed by SSR markers, parental lines having the similar genetic background from pedigree information were grouped into different clusters. The combination of pedigree analysis and SSR markers could be a more reliable method to study the diversity and grouping of parental lines of hybrid rice. Hybridization between diverse restorer and CMS groups identified from this study would be expected to yield hybrid combinations with premium grain quality and good fertility restoration.Keywords: Simple sequence repeat (SSR), maintainer and restorer genetic diversity, grain quality, fertility restorationAfrican Journal of Biotechnology Vol. 12(33), pp. 5105-5116

Studies on the agar content in Gracilaria arcuata Var. Arcuata and G. Corticata Var. Cylindrica

Studies on the yield and physical properties of agar was made for one year from March 1982 to February 1983 in Gracilaria arcuata Var. Arcuta and G. Corticata Var. Cylindrica growing in the intertidal belt at Kilakarai. In G. arcUilta var arCUllla, the agar content varied from 38.8 to 52.2% and gel strength from 11 to 67 gm/cm'. In G. corticola var. cylindrica the yield of agar ranged from 33.1 to 48.6% and gel strength from 12 to 67 gm/cm'

Seaweeds-products, processing and utilization

Seaweeds-products, processing and utilization Marine macroalgae which are popularly termed as Seaweeds belong to the primitive group of nonflowering plants known as Thallophyta. They are autotrophic plants and grow in the intertidal and subtidal regions of the sea

Distribution and seasonal changes of marine algal flora from seven localities around Mandapam

Studies on the distribution and seasonal changes in tHe marine aLgal flora was made for a period of one year from July '83 to June '84 by making fortnightly collection of algae from intertidal and subtidal regions upto 1.0 m depth at seven localities along Mandapam coast namely Rameswaram, Pamban, Krusai Island, Thonithurai, Seeniappa Darga, Pudumadam and Kilakarai. Totally 104 algal species belonging to the groups Chlorophyta, Phaeophyta, Rhodophyta and Cyanophyta were recorded from these places. A maximum number of 77 algal species at Krusadai Island and a minimum number of 35 species at Rameswaram were recorde

Coastal sand dune and its importance in near shore marine ecosystem

The coastal region along with sandy dunes, have been used by man for different activities. The dunes have been utilized without understanding the dangerous effects, their disappearance can cause to the surrounding environment. Indiscriminate cutting of coastal vegetation and over–exploitation of beach sand for developmental works have resulted in erosion of vast coastal area. Sand dunes are very important systems which require careful planning and management

Large scale exploitation of sea horse (Hippocampus kuda) along the Palk Bay coast of Tamil Nadu

The specific fishing of sea horse Hippocampus kuda commenced in June 1992 and continues actively along the Palk Bay coast of Tamil Nadu. The diving is carried out by chank and holothurian skin divers

A study on intermediate buffer layer of a coated Fiber Bragg grating cryogenic temperature sensors

The sensor characteristics of a coated Fiber Bragg grating (FBG) thermal sensor for cryogenic temperatures depends mainly on the coating materials. The sensitivity of the coated FBG can be improved by enhancing the effective thermal strain transfer between the different layers and the bare FBG. The dual coated FBG’s has a primary layer and the secondary layer. The primary coating acts as an intermediate buffer between the secondary coating and the bare FBG. The outer secondary coating is normally made of metals with high thermal expansion coefficient. In this work, a detailed study is carried out on chromium and titanium intermediate buffer layers with various coating thicknesses and combinations. To improve the sensitivity, the secondary coating layer was tested with Indium, Lead and Tin. The sensors were then calibrated in a cryogenic temperature calibration facility at Institute of Technical Physics (ITEP), Karlsruhe Institute of Technology. The sensors were subjected to several thermal cycles between 4.2 and 80 K to study the sensor performance and its thermal characteristics. The sensor exhibits a Bragg wavelength shift of 13pm at 20K. The commercially available detection equipment with a resolution of 1pm can result in a temperature resolution of 0.076 K at 20K