New record of marine tube dwelling diatoms Navicula mollis and Navicula rusticensis from South Andaman, India

294-296The occurrence of two species of marine tube dwelling diatoms was reported from the water samples collected from Phoenix Bay, South Andaman. The recorded species were Navicula mollis and Navicula rusticensis. The morphometric dimensions of these two species were also given. Along with the tube dwelling diatoms, co-habitant diatoms were also observed in the present study. This was the first report of tube dwelling diatoms from Indian waters particularly from Andaman Islands

Marine Biodiversity – Strategies for Conservation, Management and Ecological Restoration

Biodiversity is the fundamental subject of ecology, and its knowledge becomes an integral part for the assessment and conservation of any type of biota, maintains a healthy biosphere and provides direct and indirect value to human beings. Marine environment basically consists of many important biodiversity-rich ecological units. Human beings are highly depending on flora and fauna of the marine ecosystem for the various needs in their life. However, human activities have destroyed the biodiversity in these ecosystems and are mostly responsible for the degradation of all resources directly or indirectly in the earth. Reduction of a single species can affect the energy flow in the various trophic levels and resulted in reduction of biodiversity which might have some serious and long-term effects on the biosphere. To cater the increasing demand for animal protein in the world, catch of fish species are inevitable and leads to overexploitation. Sustainable use of all these resources along with effective execution of strategies and resources management techniques is essential for the conservation of biodiversity marine realm

Effect of pediveliger densities and cultch materials on spat settlement of black lip pearl oyster Pinctada margaritifera (Linnaeus, 1758) in hatchery

The settlement of hatchery produced spat of the blacklip pearl oyster Pinctada margaritifera was investigated with respect to time of introduction of settlers, type of cultch material and the larval (pediveliger) densities. The study clearly indicated that the ideal time for deployment of spat collectors in the hatchery is when the pediveligers are beginning to appear in the larval rearing tank. In similar larval stocking densities, the settlement was more on the spat collectors which were deployed when the larvae had not metamorphosed to spat. Six different types of cultch materials were tested for their efficiency in three larval densities. The study showed that better spat collection of P. margaritifera can be achieved in hatcheries by providing darkness, and employing dark coloured, rough-surfaced, corrugated and conditioned spat collectors such as the garden shade spiral at higher larval densities of 1.0 nos/ml

Growth, survival and byssal attachment of the blacklip pearl oyster Pinctada margaritifera (Linnaeus 1758) spat exposed to different salinities

The influence of salinity on growth, survival and byssal fibre attachment of the blacklip pearl oyster, Pinctada margaritifera spat was assessed. P. margaritifera enjoys a coastal distribution in the intertidal reef flats of Andaman and Nicobar Islands, with maximum density at 5 -10 m depth, where drastic changes in environmental parameters such as salinity, temperature and turbidity occur. Spat showed comparatively good growth in terms of instantaneous growth rates (IGRs) of dorso-ventral measurement (DVM), antero-posterior measurement (APM) and total weight (TWT) in a wide range of test salinities from 19 to 37 psu; IGRs were drastically decreased in spat reared at lower and higher salinities outside of this range. The highlight of the present study was better growth performance and 100% survival of P. margaritifera spat at lower salinity levels (22-28 psu) than in the ambient salinity (31 psu). The study also showed that sudden exposure to a higher salinity (above 40 psu) will be helpful for detachment of P. margaritifera spat from settlement tanks in the hatchery to facilitate stress-free spat transfer to sea farming systems. This will be useful in adopting the Japanese technique on post-operative culture for producing high quality pearls from P. margaritifera

Growth and survival of the blacklip pearl oyster Pinctada margaritifera (Linnaeus) spat reared with various combinations of microalgae in different stocking densities

The present study has revealed that, the temperature has a crucial role among the observed physiochemical parameters on the growth and survival of P. margaritifera spat. Instantaneous growth rates (IGRs) in DVM, APM and TWT were calculated and used to assess the variation in growth of spat reared with different feed mixtures (FM-1 - 8) of five diatoms and stocking densities (SD-10, 20 and 30). Among all treatments, FM-3, 4 and 5 gave better performance than that all other combinations of diatoms. Chaetoceros calcitrans, Nannochloropsis oculata and Chlorella marina was formed major shares (60%) respectively in combination with 10% each of rest of algae. FM-7 which had all diatoms in equal (20%) measure performed as the next best feed combination. Poor growth was observed in spat fed with FM-2 which was dominated by Isochrysis galbana (60%) and FM-6 which comprised of an equal measure (30%) of Pavlova salina, Isochrysis galbana, Chaetoceros calcitrans and Nannochloropsis oculata and Chlorella marina at 5% each. When the stocking density increases (SD–20 and 30) growth rates (IGRs) in all three variables decreased irrespective of feed combinations. Mortality rates varied in different treatments and also with stocking densities. Maximum mortality was observed in control (FM -8) in all the stocking densities. However, in all the feeding combinations and stocking densities, 100 % survival was observed upto the 9th DOC and mean cumulative mortalities showed a gradual increase. Comparatively very less cumulative mortality and better growth performance were recorded in stocking density, SD-10

Ophthalmological Symptom Presentations in Ear, Nose and Throat Diseases - A Cross-sectional Study from a South Indian Centre

Introduction Ophthalmological symptoms are common in ear, nose and throat conditions. Orbital involvement and ophthalmological presentations may be indicative of the extensive and aggressive nature of the pathology. This study evaluated the causes of various ophthalmological presentations in relation to primary ENT diseases in patients attending the ENT Department of a government tertiary referral teaching hospital. Material and Methods Sixty patients with ophthalmological presentations arising out of primary ENT diseases were assessed in detail. Comprehensive physical, ophthalmological and ENT examinations were done. Ophthalmological and ENT diagnoses, treatment details, outcome and complications if any were also noted. Results Most number of patients were in the age group 51 to 60 years (14; 23.4%). Most common ophthalmological symptom was periorbital oedema (51.6%) followed by epiphora (48.3%); the most common ENT symptom was headache (50%) followed by nasal discharge (48.3%). Most common diagnosis among patients was sinusitis (46.7%) followed by mucocele (21.7%). Most common (47%) otorhinological diagnosis associated with proptosis in this study was infections in the form of orbital cellulitis or abscess associated with sinusitis. Majority (43, 71.7%) of the study sample had surgical management.   Conclusion This study reiterates the need for a high index of suspicion from the part of the ophthalmologist to look beyond eye diseases as causes for ophthalmological presentations and from the part of otorhinolaryngologist to be aware of various non-ENT symptoms secondary to ear, throat and nose diseases. A close collaboration between the ophthalmology and ENT departments is essential in successful management of such patients

Silica-Based Coatings for Corrosion Protection of AA7075 Aluminum Alloy

The large economic and environmental impact caused by corrosion of metal structures has demanded new types of anti-corrosion coatings. This study proposes the application of silica-based coatings for corrosion protection of AA7075 aluminum alloy in saline environments rich in chloride ions. These coatings were obtained using the sol-gel technique. The samples were dip-coated in two types of solutions: (a) a mix of tetraethyl orthosilicate (TEOS) with 3-(Trimethoxysilyl)propyl methacrylate (TMPM) (Coating 1); and (b) a mix of titanium (IV) isopropoxide (TIP) with TMPM (Coating 2). The cure temperatures of the coatings were of 25°C, 60°C, 100°C, and 130°C, with treatment times of 1 and 3 hours. Characterization of the coatings was done by potentiodynamic polarization in aqueous saline solution (sodium chloride 3.5 %), nanoscratching, and scanning electron microscopy (SEM). The layers produced were uniform with good scratch resistance and with superior corrosion resistance when compared to the substrate

A novel approach to formulate high flux multifunctional ultrafiltration membranes from photocatalytic titania composite precursors on multi-channel tubular substrates

© 2016 The Royal Society of Chemistry.Anatase rich titanium dioxide ultrafiltration membranes with high filtration rates have been successfully developed on multi-channel tubular alumina substrates via aqueous sol-gel method from titania-alumina composite precursors containing 30 wt% alumina. The composite membrane material exhibited anatase phase stability above 800 °C and retained a BET surface area of 64 m2 g-1 even after calcination at 700 °C. Supported membranes on multi-channel substrates with an active layer thickness of 4 µm gave a water flux value of 215 L m-2 h-1 coupled with 80% rejection of Bovine Serum Albumin (BSA) with molecular weight 66 kD at 2 bar pressure. This is much higher compared to a flux of 27 L m-2 h-1 obtained for a single component titania membrane layer. The composite membrane materials showed excellent photocatalytic activity under UV irradiation such that a solution containing Methylene Blue (MB) dye showed 96% dye degradation within 2 h. Porous disc shaped substrates coated with the active titania composite layer showed methylene blue degradation of 44% under identical conditions. The present results point towards an excellent pathway for the development of multifunctional ultra-filtration membranes for water purification and also for other separation applications where separation together with photocatalysis will be of great importance

Not Available

Not AvailableThe settlement of hatchery produced spat of the blacklip pearl oyster Pinctada margaritifera was investigated with respect to time of introduction of settlers, type of cultch material and the larval (pediveliger) densities. The study clearly indicated that the ideal time for deployment of spat collectors in the hatchery is when the pediveligers are beginning to appear in the larval rearing tank. In similar larval stocking densities, the settlement was more on the spat collectors which were deployed when the larvae had not metamorphosed to spat. Six different types of cultch materials were tested for their efficiency in three larval densities. The study showed that better spat collection of P. margaritifera can be achieved in hatcheries by providing darkness, and employing dark coloured, rough-surfaced, corrugated and conditioned spat collectors such as the garden shade spiral at higher larval densities of 1.0 nos/ml.Not Availabl

Microalgal Size, density and salinity gradients influence filter feeding of <i>Pinctada margaritifera</i> (Linnaeus 1758) spat

48-54Present study has revealed the feeding performance of pearl oyster P. margaritifera spat was comparatively better in salinities ranging from 28 to 37 ppt among the tested salinities. But a perfect feeding performance was noticed with a salinity between 31 to 34 ppt. Clearance rate, ingestion rate and retention efficiency of different sized algae showed that in these salinities spat can able to do a normal feeding activities in all the tested seston concentrations. these parameters were better in the optimal algal concentration of 50 x 103 cells.ml-1. Clearance rate and ingestion rate lower with diatoms than flagellates. Salinity, size of the food particle and its concentrations are also important factors influence the ingestion rate. The ingestion rate was proportionally increased with food concentration but the retention efficiency was inversely proportional. The smaller sized Chlorella marina and Nanochloropsis oculata showed a less retention than that of the other larger algal species, Pavlova salina, Isochrysis galbana and Chaetoceros calcitrans. The study has revealed that the best live feed for the blacklip pearl oyster spat should have a size of above 3 µm with cell concentration of 25 to 50 x103 cells.ml-1 required for nursery rearing