Oceanic Light Absorption Properties: Assessment and Characterization in the Southeastern Bering Sea Using Field and Satellite Observations

In recent decades the Bering Sea has been subjected to large climatic variability with cascading consequences on its productive marine ecosystem. Long-term as well as short-term monitoring is essential if we are to maintain its capability to supply the resources on which the national and local economy depend. Remote sensing together with in-situ and laboratory measurements of physical, biological and optical properties have considerable potential for monitoring and measuring the effects of climate-driven changes on this ecosystem. A major shortcoming to obtain accurate estimates of optically active components (such as colored dissolved organic matter, non-algal particulate matter, and phytoplankton) from ocean color remote sensors has been the lack of in-situ bio-optical data in the Bering Sea. To address this issue, the central part of this dissertation was to i) assess phytoplankton absorption of culture and seawater samples using spectrophotometric and pigment reconstruction methods and ii) obtain a suite of in-water measurements for characterization and parameterization of light absorption properties in the southeastern Bering Sea. One of the main objectives was to assess the bio-optical models and parameterizations currently used in satellite algorithms for the southeastern Bering Sea, which were found to be inapplicable in these waters due to the dominant contribution by CDOM absorption. The CDOM absorption accounted for greater than 50% of the diffuse light attenuation coefficient and caused the remote sensing reflectance to be lower, more in the blue than the green region of the visible spectrum, causing the blue to green reflectance ratios to decrease by a factor of ~2. The lower specific absorption relative to lower and middle latitudes indicated significant pigment packaging and/or change in pigment composition which was consistent with variability in phytoplankton community structure. These results suggested the need for developing regional algorithms and parameterizations; regional empirical algorithms were developed using relationships between remotely sensed reflectances and properties of optically active components in the study region. The results from this dissertation will enhance our ability to achieve greater accuracy in deriving remotely measured optical parameters of sub-arctic regions required for an improved understanding of biological responses to climatic forcing

Identification of β-carotene and β-sitosterol in methanolic extract of Dipteracanthus patulus (Jacq) nees and their role in antimicrobial and antioxidant activity.

The Dipteracanthus patulus (Jacq) nees is undershrub belonging to the family acantheaceae. Antimicrobial activity (disc diffusion method) and antioxidant activity by different in-vitro methods (DPPH, hydrogen peroxide, nitric oxide radical scavenging and reducing power) of methanolic extract of Dipteracanthus patulus (MEDP) was evaluated.  The qualitative and quantitative estimation of β-carotene and β-sitosterol in MEDP was carried out by high performance thin layer chromatography (HPTLC). The total phenolic content of was determined by Folin-Ciocalteu method. Experimental findings indicate promising antimicrobial activity (antibacterial and antifungal) and potent antioxidant activity of MEDP. In addition, phytochemical analysis and spectral studies of MEDP were also performed. It is presumed that antimicrobial and antioxidant activity observed with MEDP may largely be attributed to the presence of major phytoconstituents (β-carotene, β-sitosterol and iridoid glycosides) and other minor components may participate as promoters

Particle production during inflation: constraints expected from redshifted 21 cm observations from the epoch of reionization

We examine a type of features in the primordial scalar power spectrum, namely, the bump-like feature(s) that arise as a result of burst(s) of particle production during inflation. The latest CMB observations by Planck 2018 can accommodate such features. In the near future, observations of redshifted 21 cm signal from the epoch of reionization can put additional constraints on inflation models by exploiting the expected tomographic information across a wide range of co-moving wave-numbers. In this work, we study the potential of upcoming observational data from SKA-Low to constrain the parameters of the primordial power spectrum with bump-like features. We use simulated mock data expected from SKA-Low, with uncertainties estimated from different foreground removal models, and constrain the parameters of primordial features within a Bayesian framework. We study two scenarios: in the first scenario, where the astrophysical parameters relevant to the evolution of the 21 cm signal are known, we find that 21 cm power spectra do have the potential to probe the primordial bump-like features. As the input amplitude of the bump is decreased below roughly 10% of the amplitude of the primordial power spectrum without the bump, the uncertainties in the recovered values for both amplitude and location of the bump are found to increase, and the recovered values of the location of the bump also get increasingly more biased towards higher values. Hence, it becomes harder to constrain these parameters. In the second scenario, we analyze the achievable constraints on primordial features when two of the astrophysical parameters, namely, minimum halo mass and ionizing efficiency are uncertain. We find that the effect of the bump on the shape and the amplitude of the 21 cm power spectrum is distinct from the impact of varying the astrophysical parameters, and hence they may potentially be distinguished.Comment: 26 page

Physico-chemical Analysis of beeswax procured from Mumbai market, Western Ghats (Natural Habitat)

Beeswax is the substance that is obtained from the structure of a honey comb. The bees secrete wax to build the honey combs to store honey. It has rich hydrophobic property, the beeswax is in fact present within cosmetics and body products. Also, beeswax is used in food industry. Beeswax is a complex mixture of hydrocarbons, free fatty acid, esters of fatty acid. Beeswax plays an important role in Ayurvedic medicine, the traditional medicine name with Madhushistha (Beewax). The Madhushistha is used for the care of wound from abrasion or even from burns with topical application. Some references in Ayurvedic granth highlight the use of Madhushistha in combination with other herbal and mineral mixture, like Sikta Taila, Mruddaharshringa, Jatyadi Taila, etc. Beeswax is mainly of two types, natural beeswax and processed beeswax. Natural beeswax is clarified further heating in water with petroleum waxes. Because of high demand and shortage in market, adulteration of beeswax with cheaper materials are common like animal fat, plant oil and petroleum spirits (Paraffin wax). Hence authenticity of beeswax is major concern and that can be determined by using physico-chemical parameters such as- organoleptic test, solubility, Melting point, Spacific gravity, Refractive index, Acid value, Ester value, Saponification value, volatile matter. With this justification the present study is expected to determine the quality status of four different beeswax samples procured from Mumbai market, western ghats (Natural habitat). The physico-chemical analysis revealed that volatile matter is detected in market sample (2) whereas market sample (1) shows higher melting point as compare to beeswax collected from the Natural habitat. Market sample (1,2) of beeswax shows slight adulteration hence natural habitat samples (1,2) of beeswax should be used in medicine preparation

A case of abdominal tuberculosis presenting as obstructive jaundice

Extrapulmonary tuberculosis is notorious for its many manifestations, which can lead to delayed diagnosis and treatment. In particular, abdominal tuberculosis is easily overlooked because the incidence is low and because it can mimic common non-infectious abdominal syndromes. We describe here a 45-year-old female presenting with obstructive jaundice. In this patient, a pancreatic mass was found and tuberculosis was first diagnosed after a diagnostic laparoscopic. Tuberculosis should be included in the differential diagnosis of intra-abdominal mass lesions, especially in persons originating from regions where tuberculosis is endemic. Invasive procedures are often required to obtain adequate diagnostic samples

A case of recurrent achalasia cardia with sigmoid esophagus managed laparoscopically

Recurrences of symptoms after the surgery for achalasia cardia are not uncommon. There are several causes of recurrences but the early recurrences are thought to be secondary either to incomplete myotomy or late recurrences due to fibrosis after the myotomy or megaesophagus. A laparoscopic approach is a standard method because of the obvious benefits for the patients. The extent of the myotomy and addition of fundoplication are debatable issue in the management of achalasia cardia but evidence suggests that some kind of fundoplication would be necessary after the complete division of lower esophageal sphincter. We present our experience in a case of recurrent achalasia, secondary to incomplete myotomy managed laparoscopically by extended myotomy and a Dors fundoplication

Anal mucosal melanoma presenting as per rectal bleed: a case report

Anorectal mucosal melanoma is a rare, malignant and aggressive tumor that usually presents late. It primarily arises from the melanocytes but can also arise from the mucosal surface. It also carries poor survival rates. Early diagnosis of the disease and prompt treatment is necessary. Overall 5-year survival rate for anal melanoma is below 10%. We present a case of a 77 years old male patient who presented with chief complaints of per rectal bleeding and decreased appetite. Patient’s symptoms were initially confused for benign conditions like hemorrhoids. He was diagnosed with anal mucosal melanoma on per rectal biopsy. Patient’s radiological investigations including PET scan and MRCP were suggestive of liver and lung metastasis. In view of the advanced stage of the disease, the decision was taken to treat the patient conservatively. He was started on imatinib therapy and a regular follow up was kept and palliative care was provided

Altered Ca(2+ )homeostasis in polymorphonuclear leukocytes from chronic myeloid leukaemia patients

BACKGROUND: In polymorphonuclear leukocytes (PMNL), mobilization of calcium ions is one of the early events triggered by binding of chemoattractant to its receptors. Besides chemotaxis, a variety of other functional responses are dependent on calcium ion mobilization. PMNL from chronic myeloid leukaemia (CML) patients that were morphologically indistinguishable from normal PMNL were found to be defective in various functions stimulated by a chemoattractant – fMLP. To study the mechanism underlying defective functions in CML PMNL, we studied calcium mobilization in CML PMNL in response to two different classical chemoattractants, fMLP and C5a. RESULTS: Release of calcium estimated by flow cytometry and spectrofluorimetry using fluo-3 as an indicator showed that the [Ca(2+)](i )levels were lower in CML PMNL as compared to those in normal PMNL. But, both normal and CML PMNL showed maximum [Ca(2+)](i )in response to fMLP and C5a at 10 sec and 30 sec, respectively. Spectrofluorimetric analysis of the total calcium release in chemoattractant treated PMNL indicated more and faster efflux of [Ca(2+)](i )in CML PMNL as compared to normal PMNL. CONCLUSION: Fine-tuning of Ca(2+ )homeostasis was altered in CML PMNL. The altered Ca(2+ )homeostasis may contribute to the defective functions of CML PMNL