Gynostemium morphology and floral biology of Thottea duchartrei Sivar., A.Babu & Balach. (Aristolochiaceae), an endemic species from Western Ghats, India

Gynostemium is a putative floral structure formed by the fusion of the male and female reproductive parts (stamens and carpels) through a process during its development called synorganization. Most of the Indian species of Thottea Rottb. have a prominent gynostemium in their floral architecture, with varying degrees of adnation and complexity. Even though the gynostemium is a significant taxonomic marker for the inter-specific systematics in Thottea, the scepticism and arguments on deciphering its morphology and functional parameters, including the existence of staminodes, makes it imperative to be examined in detail. The present study is the first attempt in this line which aims to explore the morphological characters of gynostemium and reproductive biology of Thottea duchartrei Sivar., A.Babu and Balach., an endemic species in the Western Ghats. Stereo zoom microscopy, SEM and reproductive biological studies were conducted providing special emphasis to the gynostemium. Detailed analysis revealed the structural and functional diversity of gynostemium with regard to its components. The study also helped to recognize the columnar outgrowths on the gynostemium as staminodes. In total, the present study helps to solve the confusions regarding the functional identity of the gynostemium T. duchartrei with regard to its morphology

Toxic Metals Enrichment in the Surficial Sediments of a Eutrophic Tropical Estuary (Cochin Backwaters, Southwest Coast of India)

Concentrations and distributions of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in surficial sediments of the Cochin backwaters were studied during both monsoon and pre-monsoon periods. Spatial variations were in accordance with textural charaterstics and organic matter content. A principal component analysis distinguished three zones with different metal accumulation capacity: (i) highest levels in north estuary, (ii) moderate levels in central zone, and (iii) lowest levels in southern part. Trace metal enrichments are mainly due to anthropogenic contribution of industrial, domestic, and agricultural effluents, whose effect is enhanced by settling of metals due to organic flocculation and inorganic precipitation associated with salinity changes. Enrichments factors using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. An assessment of degree of pollution-categorized sediments as moderately polluted with Cu and Pb, moderately-to-heavily polluted with Zn, and heavily-to-extremely polluted with Cd. Concentrations at many sites largely exceed NOAA ERL (e.g., Cu, Cr, and Pb) or ERM (e.g., Cd, Ni, and Zn). This means that adverse effects for benthic organisms are possible or even highly probable

Molecular, Crystalline, and Lamellar Length-Scale Changes in the Poly(l‑lactide) (PLLA) during Cyclopentanone (CPO) Desorption in PLLA/CPO Cocrystals

Polymer–solvent complexes, poly­(l-lactide) (PLLA) with cyclopentanone (CPO), were studied at multiple length scales using differential scanning calorimetry, small-angle neutron scattering, Fourier transform infrared spectroscopy, and temperature-dependent wide- and small-angle X-ray scattering. PLLA crystallizes in the ε form when organic solvents such as CPO are incorporated into the crystal lattice at subambient temperatures. The transformation of this structure into the α form during solvent desorption and the accompanying changes in the lamellar structure were followed by various measurements on PLLA/CPO cocrystals. SANS data suggest that CPO is present stoichiometrically in the crystal lattice and as clusters in the interlamellar amorphous regions in the nominally dried samples. DSC thermogram showed a sharp endotherm during this ε to α transition. X-ray fiber diagrams showed that the ε form transforms to the α form over a temperature range (40–55 °C) as the solvent molecules are expelled from the crystalline lattice, while maintaining chain orientation. Infrared spectra showed the splitting of the CH₃ symmetric deformation band at 1383 cm^–1 into a doublet (1382 and 1386 cm^–1) at ε to α transition, indicating the desorption of CPO molecules from the crystal lattice. Changes in the invariant in SAXS data are interpreted as due to the migration of the solvent from the crystalline phase to the amorphous phase during the ε to α transition followed by the evaporation of the solvent from the entire polymer. During this transition, lamellae that are tilted in the presence of CPO in the crystal lattice become perpendicular to the chain axis. In addition, there are changes in long period, lamellar thickness, and amorphous thickness. Continuing the desorption to dryness by further heating results in the removal of the solvent molecules in the amorphous phase of the α form. This is accompanied by increased crystallinity. These studies show that the solvent desorption results in a precise sequence of quantifiable structural changes at multiple length scales

ToxicMetals Enrichment in the Surficial Sediments of a Eutrophic Tropical Estuary (Cochin Backwaters, Southwest Coast of India)

Concentrations and distributions of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in surficial sediments of the Cochin backwaters were studied during both monsoon and pre-monsoon periods. Spatial variations were in accordance with textural charaterstics and organic matter content. A principal component analysis distinguished three zones with different metal accumulation capacity: (i) highest levels in north estuary, (ii) moderate levels in central zone, and (iii) lowest levels in southern part. Trace metal enrichments are mainly due to anthropogenic contribution of industrial, domestic, and agricultural effluents, whose effect is enhanced by settling of metals due to organic flocculation and inorganic precipitation associated with salinity changes. Enrichments factors using Fe as a normalizer showed that metal contamination was the product of anthropogenic activities. An assessment of degree of pollution-categorized sediments as moderately polluted with Cu and Pb, moderately-to-heavily polluted with Zn, and heavily-to-extremely polluted with Cd. Concentrations at many sites largely exceed NOAA ERL (e.g., Cu, Cr, and Pb) or ERM (e.g., Cd, Ni, and Zn). This means that adverse effects for benthic organisms are possible or even highly probable.Cochin University of Science & TechnologyThe ScientificWorld Journal Volume 2012, Article ID 972839, 17 page

Possible Effects of Perchlorate Contamination of Drinking Water on Thyroid Health

Background. Perchlorate is an anion that occurs as a contaminant in groundwater. It originates from the improper disposal of ammonium perchlorate, a component of rocket fuel. The objective of this study was to explore whether the exposure to perchlorate in drinking water had an impact on the thyroid function of the population residing near an ammonium perchlorate plant in Kerala. Methodology. Using an ecological study design, we compared the serum levels of thyroid-stimulating hormone, thyroxine, and thyroid peroxidase antibodies among a representative sample of 289 study subjects from the area surrounding the ammonium perchlorate enrichment plant to 281 study subjects in a control area. Results. The perchlorate concentration in the groundwater varied from 1600 ppb to 57,000 ppb in the 10 samples from the contaminated area and was below 24 ppb in all locations in the control area. No significant differences were found in the mean serum TSH concentration and mean T4 levels between the subjects from the contaminated area and the control area. On regression analysis, perchlorate contamination was not found to be a significant predictor of TSH. Conclusion. This study did not find any significant association between perchlorate in drinking water and changes in thyroid hormone levels. Our findings indicate the need for further investigation of this hypothesis using urinary perchlorate as a measure of individual exposure