Research in the assessment of capture and culture fisheries along the Indian coast

A review of the research conducted at National Institute of Oceanography, Goa to assess the capture and culture fishery potential of India is presented in the paper- the primary, secondary and benthic productivity of estuaries and backwaters are elucidated by taking the Mandovi-Zuari estuarine system as an example. The productivity of the coastal and oceanic waters around India are discussed. The expected fishery yield and present level of exploitation are assessed and further course of action discussed in this paper, in culture fisheries the contributions of NIO in the fields of mussel culture, shrimp culture, brine shrimp culture, seaweed culture, horse-shoe crab culture and fish culture are reviewed and discussed

Porosity of core-shell nanoparticles

The porosity of titania and zirconia covered Ag and Au nanoparticles has been investigated using the metal core reactivity as a probe. The presence of pores was confirmed by a newly discovered reaction between halocarbons and core-shell nanoparticles, in which the core gets converted into ions, which are leached out through the shell. Halocarbons having different alkyl chain lengths react with metal cores at different rates due to the differences in the accessibility of the core. It is also observed that the electrochemical accessibility of the core can be reduced by blocking the pores by adsorbates such as cis-dithiocyanato-bis(2,2'-bipyridyl-4,4'- dicarboxylic acid)ruthenium(II) dye (popularly called N3 dye). With the adsorbed dye molecules on the oxide shell, metal cores are stable for extended periods of time even after the addition of halocarbons. The porosity of the Au@SiO2 system, in which a silica shell is formed over the metal clusters through monolayers, has also been studied. Our studies show that the porosity of different kinds of shells is largely similar, allowing molecular and ion penetration

Chemical interactions at noble metal nanoparticle surfaces - catalysis, sensors and devices

In this paper, a summary of some of the recent research efforts in our laboratory on chemical interactions at noble metal nanoparticle surfaces is presented. The article is divided into five sections, detailing with (i) interactions of simple halocarbons with gold and silver nanoparticle surfaces at room temperature by a new chemistry and the exploitation of this chemistry in the extraction of pesticides from drinking water, (ii) interaction of biologically important proteins such as Cyt c, hemoglobin and myoglobin as well as a model system, hemin with gold and silver nanoparticles and nanorods forming nano-bio conjugates and their surface binding chemistry, (iii) formation of polymer-nano composites with tunable optical properties and temperature sensing characteristics by single and multi-step methodologies, (iv) nanomaterials-based flow sensors and (v) composites of noble metal nanoparticles and metallic carbon nanotubes showing visible fluorescence induced by metal-semiconductor transition

Nonlinear light transmission through oxide-protected Au and Ag nanoparticles: an investigation in the nanosecond domain

Stable Au and Ag nanoparticles protected with TiO2, ZrO2, and SiO2 shells show saturable absorption when excited with moderately energetic nanosecond pulses at 532 nm, but exhibit strong optical limiting at higher intensities. The behavior is explained in terms of the induced optical nonlinearity and nonlinear light scattering. The inherent stability of the core-shell structure renders a high laser damage threshold to these materials, making them promising candidates for high energy optical limiting

HIV/AIDS Education for Adolescents

BackgroundAmong adolescents, girls are particularly vulnerable not only because they are more likely to be coerced for unprotected sex but also because they are more susceptible biologically to sexually transmitted diseases (STDs), including HIV infection. This study was carried out to determine the effectiveness of an educational intervention programme aimed at girls focusing on knowledge of and attitude to HIV/AIDS. MethodAn educational intervention study was carried out among 791 rural girls (16-19 years) randomly selected using stratified cluster sampling from coastal villages in Udupi Taluk, Karnataka, Southern India. They were educated regarding HIV/AIDS and their awareness levels were evaluated immediately and one month following intervention. Results Around 35-50% of the girls had misconceptions regarding the modes of transmission which significantly reduced to about 8 % after intervention (95% CI of difference in proportion = (9.2, 17.9);

Quantitative Metabolomics by 1H-NMR and LC-MS/MS Confirms Altered Metabolic Pathways in Diabetes

Insulin is as a major postprandial hormone with profound effects on carbohydrate, fat, and protein metabolism. In the absence of exogenous insulin, patients with type 1 diabetes exhibit a variety of metabolic abnormalities including hyperglycemia, glycosurea, accelerated ketogenesis, and muscle wasting due to increased proteolysis. We analyzed plasma from type 1 diabetic (T1D) humans during insulin treatment (I+) and acute insulin deprivation (I-) and non-diabetic participants (ND) by 1H nuclear magnetic resonance spectroscopy and liquid chromatography-tandem mass spectrometry. The aim was to determine if this combination of analytical methods could provide information on metabolic pathways known to be altered by insulin deficiency. Multivariate statistics differentiated proton spectra from I- and I+ based on several derived plasma metabolites that were elevated during insulin deprivation (lactate, acetate, allantoin, ketones). Mass spectrometry revealed significant perturbations in levels of plasma amino acids and amino acid metabolites during insulin deprivation. Further analysis of metabolite levels measured by the two analytical techniques indicates several known metabolic pathways that are perturbed in T1D (I-) (protein synthesis and breakdown, gluconeogenesis, ketogenesis, amino acid oxidation, mitochondrial bioenergetics, and oxidative stress). This work demonstrates the promise of combining multiple analytical methods with advanced statistical methods in quantitative metabolomics research, which we have applied to the clinical situation of acute insulin deprivation in T1D to reflect the numerous metabolic pathways known to be affected by insulin deficiency

Effect of Testosterone on Insulin Stimulated IRS1 Ser Phosphorylation in Primary Rat Myotubes—A Potential Model for PCOS-Related Insulin Resistance

Polycystic ovary syndrome (PCOS) is characterized by a hyperandrogenic state and frequently develops skeletal muscle insulin resistance. We determined whether testosterone adversely affects insulin action by increasing serine phosphorylation of IRS-1(636/639) in differentiated rat skeletal muscle myotubes. The phosphorylation of Akt, mTOR, and S6K, downstream targets of the PI3-kinase-IRS-1 complex were also studied.Primary differentiated rat skeletal muscle myotubes were subjected to insulin for 30 min after 16-hour pre-exposure to either low (20 ng/ml) or high (200 ng/ml) doses of testosterone. Protein phosphorylation of IRS-1 Ser(636/639), Akt Ser(473), mTOR-Ser(2448), and S6K-Thr(389) were measured by Western blot with signal intensity measured by immunofluorescence.Cells exposed to 100 nM of insulin had increased IRS-1 Ser(636/639) and Akt Ser(473) phosphorylation. Cells pre-exposed to low-dose testosterone had significantly increased insulin-induced mTOR-Ser(2448) and S6K-Thr(389) phosphorylation (p<0.05), and further increased insulin-induced IRS-1 Ser(636/639) phosphorylation (p = 0.042) compared to control cells. High-dose testosterone pre-exposure attenuated the insulin-induced mTOR-Ser(2448) and S6K-Thr(389) phosphorylation.The data demonstrated an interaction between testosterone and insulin on phosphorylation of intracellular signaling proteins, and suggests a link between a hyperandrogenic, hyperinsulinemic environment and the development of insulin resistance involving serine phosphorylation of IRS-1 Ser(636/639). These results may guide further investigations of potential mechanisms of PCOS-related insulin resistance