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The present study examined the seasonal cycling of phosphorous (P) along the southwest coast of India (SWCI) based on two cruises during the southwest monsoon (SWM) and northeast monsoon (NEM) of 2018. During SWM, the entire SWCI experienced intense upwelling manifested by the incursion of cold, nutrient-rich, and hypoxic waters. During NEM, the region was transformed into a warm, well-oxygenated and nutrient-deplete environment. Dissolved inorganic phosphorus (DIP) was significantly high in the subsurface during SWM due to its release from sediments. The sediment P was high and showed an increasing trend towards the south, principally dependent on the sediment texture, organic carbon, and Fe concentrations. Bioavailable P, the sum of exchangeable (PEx) and reducible (PFe) fractions, was almost consistent (5-20%) over seasons, though PFe showed a marked reduction during SWM. Authigenic fraction (PAut) was the most dominant (46%), followed by detrital (PDet 41%) and residual (PRes 8%) fractions. Principal component analysis (PCA) of geochemical parameters for SWM was indicative of the high dissolution of Fe (oxy)hydroxides under hypoxia releasing P and its complexation with organic matter and Fe. PCA results for the NEM were different, as it indicated increased preservation of P-associated organic matter and Fe, alternately favouring the formation of PAut in sediments. The study's significance is the observation that the bottom water oxygen concentration can significantly influence sedimentary P cycling in tropical coastal upwelling zones.

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This study investigates the influence of upwelling induced seasonal hypoxia in the sediment-water interface on the distribution, bioavailability and geochemical partitioning of selected trace metals in surficial sediments along the southwest coast of India based on two successive cruises. The first cruise was during the southwest monsoon (SWM) season when coastal waters exhibited intermittent bottom hypoxia due to upwelling. The second cruise during the northeast monsoon (NEM) season was characterised by a uniformly warm and well-oxygenated water column in the study region. The results showed that grain size, organic carbon and Fe are the major factors influencing the distribution of trace metals in the surface sediments. Based on the geochemical indices (contamination factor, enrichment factor and geo-accumulation factor), the study region appears to be moderately contaminated by Ni, Cr, and Pb. Based on the ecological risk assessment criteria, the enrichment of Pb, Cr and Ni may cause adverse effects on the benthic organisms. The fractionation studies demonstrated that the major pathway of metal deposition in the sediment is lithogenic. The data also showed that labile and organic fractions are the second dominant forms, while other fractions (exchangeable and carbonate) are insignificant. The consistency in the reactive Fe concentrations during SWM and NEM could be due to the absence of Fe dissolution in sediments under mild reducing condition (intermittent hypoxia). In addition to the above, an enrichment of organic matter also leads to increased deposition of trace metals in sediments. Conversely, the secondary phase enrichment factor and risk assessment code calculated based on the metal fractionation data indicated low risk and contamination along the southwest coast of India except for Zn that showed moderate contamination in some transects. The study provides the need for regular geochemical assessment to control metal pollution in the coastal environment, which is a major resource of the fishery.

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The combination of ectrodactyly, ectodermal dysplasia, and cleft lip with or without cleft palate (EEC syndrome) is a rare type of congenital anomaly. It usually occurs as an autosomal-dominant trait or less commonly in a sporadic form. In this complex, multiple congenital anomaly syndrome, any of the three cardinal manifestations may present with variable expressions.

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A 24-year-old female presented with a firm, hyperpigmented, and gradually enlarging, tender, solitary dermal nodule of non-traumatic origin over the right suprascapular region. The lesion was extending into the subcutaneous tissue. She was otherwise normal. There was no calcification on X-ray. Biopsy revealed numerous large pleomorphic fibroblasts in a mucoid ground substance diagnostic of nodular fasciitis. No recurrence was noticed after surgical excision. This case is reported because of its rarity in the Indian medical literature.

RESUMEN

A case of Squamous cell Carcinoma arising in discoid lupus erythematosus of 10 years duration is described. The constant exposure to U-V rays in sunlight, in addition to the chronic hypoxidosis in the scar resulting from chronic discoid iupus erythematosus, is assumed to induce malignant degeneration.