Role of tide and lunar phases on the migration pattern of juvenile Hilsa shad (Tenualosa ilisha) within a meso-macrotidal estuary.

Tide and lunar phases often influence the behaviour and life cycle of different fishes, especially migratory species. In the Hooghly River estuary, Hilsa shad is an anadromous fish species that migrates from the adjacent sea to the estuary and rivers for spawning. After spawning, the juveniles remain in the rivers and estuary for few months then start their downstream migration towards the adjacent sea. However, the pattern of their downstream migration has not been studied in detail so far. This study investigates the role of tide and lunar phases on the juvenile Hilsa shad migration pattern. In this study, we have estimated the rate of juveniles migrating through the river channel (no. m-2  h-1 ) during high tide and low tide in all of the lunar phases. The number of juvenile Hilsa shad fishes is found to be much higher during low tides in most of the observations and there is a significant difference (t = 11.904, P < 0.001) between the high tide and low tide catches in the entire study region. Among the eight lunar phases, the number of juveniles is also observed to be higher during the new moon and full moon, and there is also a significant difference in juvenile catch among the lunar phases (F = 64.372, P < 0.001) in the entire stretch of the study area. These observations enabled us to develop a plausible mechanism of the downstream migration of Hilsa shad juveniles.

The clinical conundrum of a catecholamine secreting giant adrenal myelolipoma.

Adrenal myelolipomas are uncommon tumours of unknown aetiology. They arise from the adrenal cortex and comprise lipomatous and myeloid elements. They are considered to be functionally inert, and metabolic evaluation is not mandatory for them. Adrenal myelolipomas can rarely be functionally active, and patients may present with hypertension, electrolyte imbalance or features of Cushing's syndrome. The association of these tumours with catecholamine secretion is exceptionally rare. We describe a case of a functional adrenal myelolipoma associated with catecholamine secretion in a 55-year-old female patient with a history of hypertension. The surgical excision of the mass resulted in normalisation of the urinary catecholamine levels and resolution of the hypertension.

Economic incentives drive the conversion of agriculture to aquaculture in the Indian Sundarbans: Livelihood and environmental implications of different aquaculture types.

Expansion of aquaculture in the Sundarbans Biosphere Reserve (SBR) is irreversibly replacing agricultural land and the drivers of this change are disputed. Based on in-depth interviews with 67 aquaculture farmers, this paper characterizes major aquaculture types in the SBR, their impacts, and identifies drivers of conversion from agricultural land. Aquaculture types included traditional, improved-traditional, modified-extensive, and semi-intensive systems. Extensive capture of wild shrimp larvae is environmentally harmful but constitutes an important livelihood. Semi-intensive aquaculture of exotic shrimp (Litopenaeus vannamei) has much higher unit-area profitability than other types but involves greater financial risk. Profitability is the main driver for the transition from agriculture, but environmental factors such as lowered crop yields and cyclone impacts also contributed. Many conversions from agriculture to aquaculture are illegal according to the stakeholders. Existing legislation, if enforced, could halt the loss of agriculture, while the promotion of improved-traditional aquaculture could reduce the demand for wild seed.

Existing Policies/Guidelines on the Environmental Dimension of Antimicrobial Resistance in India: An Insight into the Key Facets through Review and SWOT Analysis.

BACKGROUND: Antimicrobial resistance (AMR) is a multidimensional phenomenon. The environment acts as a mixing pot of drug-resistant bacteria from many sources such as pharmaceutical, biomedical, veterinary, and agricultural sectors. In this study, we analysed the existing AMR-related policies/guidelines/legislations in India in the above domains and how the current practices are being guided by them. METHODS: We used a convergent parallel mix method design. Quantitative data were collected through a review of policies/guidelines/legislations in the said domains and analysed using the SWOT tool parallelly supported by key informant interviews of domain-specific stakeholders. RESULTS: Altogether, 19 existing AMR policies/guidelines/legislations were identified. The existence of few policies/guidelines in each domain indicated the evolving environment for policy interventions. However, the lack of capacity among farmers, inadequate provision for structured capacity building, high cost of alternatives to antimicrobials, and lack of provision of incentivisation in case of crop failure were identified as the major weaknesses prevalent across the domains. Opportunities for policy refinements/the introduction of new policies are ample. However, easy access to antimicrobials and injudicious use imposes threats to AMR containment in all sectors. CONCLUSIONS: Despite having a few policies for the containment of AMR, their implementation witnesses challenge due to the lack of collaborative approaches, the existence of policies disjointed from ground reality, infrastructural issues, and the lack of capacity and resources.

Dorsal Vertebral Enhancement Mimicking Sclerosing Metastases in Lung Cancer.

We report cases of vertebral body enhancement in patients with superior vena cava and brachiocephalic venous obstruction appearing as sclerotic metastases in post-contrast CT.A 58-year-old male presented with right lung mass compressing the superior vena cava.Sclerotic areas seen involving few vertebrae in post-contrast scans.Another patient, 64-year-old female with right lung mass and narrowing of left brachiocephalic vein, sclerosis of lower cervical and upper dorsal vertebrae were seen in contrast studies. In both cases after resolution of pathology following treatment showed no enhancement in post contrast scan which was attributed to the collaterals arising due to obstruction, obviously not seen in metastases. Keywords: Brachiocephalic vein obstruction; computed tomography CT; superior vena cava SVC; vertebral enhancement; venous collaterals.

Rare Case of Metastatic Pleomorphic Liposarcoma of Thigh Presenting as Ewing's Sarcoma.

Liposarcoma is an uncommon group of tumors in the pediatric population. Of the various known subtypes,pleomorphic liposarcoma is the most infrequent in children.We present the case of a 7-year old child coming to the radiology department for evaluation of a right knee swelling. Plain radiograph and corresponding MRI images showed features of primary bone tumor possibly Ewing's sarcoma in right distal femur. The child developed right shoulder pain and CT thorax abdomen was done which revealed retroperitoneal mass with hepatic and pulmonary metastases.Subsequent core needle biopsy from the femur confirmed metastatic liposarcoma with pleomorphic features, extremely rare in childhood.The very rare incidence of metastasis that too presenting as a common primary tumor the misdiagnosis of which could result in catastrophic fate. So it's of prime importance that clinicians should be aware of this entity. Keywords: FISH; liposarcoma; myxiod dedifferentiated liposarcoma; pleomorphic liposarcoma; softsarcoma.

Summer methane emissions from sewage water-fed tropical shallow aquaculture ponds characterized by different water depths.

Aquaculture practices are steadily increasing to meet the fish demand, especially in tropical countries like India. However, efforts to characterize the contribution of these aquaculture ponds towards greenhouse gas emission like CH4 are still very few. CH4 concentration in water [pCH4(water)] and air-water CH4 fluxes were estimated (during the summer months) in two sewage-fed ponds having different depths situated in the East Kolkata Wetlands, India (a Ramsar site). pCH4(water) in both of these ponds showed significant positive correlation with water temperature (R2 = 0.68 and 0.71, p < 0.05). Daily mean chlorophyll-a, turbidity, biochemical oxygen demand (BOD) and gross primary productivity (GPP) also showed positive correlation with pCH4(water). This indicated that higher primary production and presence of turbid materials acted as substrates for methanogenesis, which favoured air-water CH4 effluxes towards atmosphere. Mean air-water CH4 fluxes in the ponds having depth of 1.1 m and 0.6 m were observed to be 24.79 ± 12.02 mg m-2 h-1 and 6.05 ± 3.14 mg m-2 h-1 respectively. Higher depth facilitated net heterotrophic conditions, which led to lower dissolved oxygen levels, which, in turn, led to lower rate of CH4 oxidation. Moreover, under reduced photosynthetically active radiation (in the pond having greater depth), the pH values were comparatively lower (~7.7), which further facilitated a favourable condition for the methanogens to grow. On the whole, it was inferred that apart from pre-established physicochemical factors, depth was also found to play a decisive role in regulating the air-water CH4 fluxes from these aquaculture ponds. In future, continuous sampling should be carried out (by chamber method) to take into account the ebullition CH4 fluxes, and more number of ponds should be sampled throughout a complete annual cycle to have a more holistic understanding about this cluster of sewage-fed aquaculture ponds.

CO2 fluxes from aquaculture ponds of a tropical wetland: Potential of multiple lime treatment in reduction of CO2 emission.

Partial pressure of CO2 in water [pCO2(water)] and air-water CO2 flux were estimated in two aquaculture ponds (one received no lime treatment (NTP) and in the other lime treatment was performed (LTP) four times a year) every month throughout an annual cycle, situated in East Kolkata Wetlands, a Ramsar Site in eastern India. It was hypothesized that lime treatment can potentially lower the pCO2(water) in aquaculture ponds and hence make these aquatic bodies sinks for CO2. The results portrayed that NTP acted as a source of CO2 throughout the year (annual mean: 1929 ±â€¯1397 µmol m-2 h-1), whereas, LTP acted as CO2 sinks post lime addition (monthly mean ranged from -366 ±â€¯16 to -449 ±â€¯32 µmol m-2 h-1), though the effect of lime addition was found to diminish by the next month and it acted as source for CO2 in the months when no lime treatment was done (LTP annual mean: 1010 ±â€¯1617 µmol m-2 h-1). Lime treatment increased the pH level and reduced the turbidity which facilitated optimum photosynthesis and the productivity increased rapidly. Beyond the critical pH value of 8.9-9.0, the pCO2(water) values became under-saturated with respect to atmospheric CO2 concentration. The effect of lime treatment was not found to prevail in the following months as a steady source of sewage from the Kolkata metropolis which feeds these aquaculture constantly bring in a huge carbon source both in inorganic and organic form. As soon as the flocculation effect of the lime dies off, the water column starts becoming turbid again which aids in converting the system into a net heterotrophic one from a net autotrophic. Based on the results we could successfully accept our hypothesis that lime treatment can not only reduce the CO2 emission but also make the system a CO2 sink.

An index for discrimination of mangroves from non-mangroves using LANDSAT 8 OLI imagery.

Over the last few decades several vegetation indices were used to map Mangrove forest using satellite images. Difficulty still persists in discrimination of mangroves from non-mangrove vegetation, especially in areas where mangrove species are mixed with other vegetation types. In the present study we have attempted to develop an improved index, which utilizes the information from the Normalized Difference Vegetation Index (NDVI) and the Normalized Difference Water Index (NDWI) of Bhitarkanika mangrove forest of Odisha, India. These indices are negatively correlated (r = -0.988; p < 0.01). Further, the NDWI values were subtracted from the NDVI values at the pixel level. As the outputs are negatively related, subtraction increases the upper and lower range of the overall output, also increasing the distinct values of two classes with near-similar spectral signatures. Same algorithm was applied on mangroves of Sundarbans (r = -0.987) and Andaman (r = -0.989). A comparison between four established indices [NDVI, NDWI, Soil Adjusted Vegetation Index (SAVI), Simple Ratio (SR)] and the newly developed index namely Combined Mangrove Recognition Index (CMRI) were performed. Accuracy assessment using Kappa statistics, revealing that CMRI produces better accuracy (73.43%) compared to other indices, followed by NDVI (56.29%) and SR (48.79%).