Publications by authors named "Avisek Dutta"

Both lanthanide-containing and fluorine-containing nanomaterials present challenging targets for microbial biosynthesis because these elements are toxic to most bacteria. Here, we overcome these challenges by using an Antarctic Shewanella baltica strain that tolerates these elements and report the first biosynthesis of lanthanide-doped fluoride nanoparticles (NPs) from them. NaYF NPs doped with Er/Yb are prototypical lanthanide-based upconverting nanoparticles (UCNPs) with upconverted luminescence at visible wavelengths under infrared excitation.

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Conjugated polymers with chiral side chains are of interest in areas including chiral photonics, optoelectronics, and chemical and biological sensing. However, the low dissymmetry factors of most neat polymer thin films have limited their practical application. Here, a robust method to increase the absorption dissymmetry factor in a poly-fluorene-thiophene (PF8TS series) system is demonstrated by varying molecular weight and introducing an achiral plasticizer, polyethylene mono alcohol (PEM-OH).

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Designing polymeric systems with ultra-high optical activity is instrumental in the pursuit of smart artificial chiroptical materials, including the fundamental understanding of structure/property relations. Herein, we report a diacetylene (DA) moiety flanked by chiral D- and L-FF dipeptide methyl esters that exhibits efficient topochemical photopolymerization in the solid phase to furnish polydiacetylene (PDA) with desired control over the chiroptical properties. The doping of the achiral gold nanoparticles provides plasmonic interaction with the PDAs to render asymmetric shape to the circular dichroism bands.

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Transition-metal-doped semiconductor nanocrystals have received significant attention because of their attractive features deeming them invaluable in various technological fields including optoelectronics, bio-photonics, and energy conversion, to name a few. Of particular, these interests are two-dimensional materials with useful optical and magnetic properties combined with their large surface areas opening up new applications in biotechnology. These applications range from multimodal optical and magnetic bioimaging and sensing to measuring the weak magnetic field due to brain waves using their magneto-optic properties stemming from the exchange interaction between the transition metal dopants and the carrier spins.

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Advancing the emerging area of chiral photonics requires modeling-guided concepts of chiral material design to enhance optical activity and associated optical rotatory dispersion. Herein, we introduce conformational engineering achieved by tuning polymer backbone conjugation through introduction of thiophene structural units in a chiral fluorene polymer backbone. Our theoretical calculations reveal a relationship between the structural conformation and the resultant rotational strength.

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Objective: To compare recurrence rate and side effects with two different maintenance regimens of postoperative intravesical therapy with mitomycin and BCG in T1 bladder cancer.

Methods: Eighty were enrolled in this study and all received immediate post operative mitomycin. They were then allocated to two groups of 40, one group receiving intravesicle BCG and other a combination BCG and Mitomycin.

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Aim: In this study our idea is to compare the effectiveness of using interposing layer of fibrin glue to omental flap in reducing the failure of laparoscopic vesicovaginal fistula repair.

Methods: Forty patients with fairly large vesicovaginal fistula were enrolled and divided in two groups of 20 each. We have used fibrin glue in one group and omental flap in the other group.

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Considerable attention has been paid to designing graphene based 2D hybrid nanostructures for their potential applications in various areas from healthcare to energy harvesting. Herein, we have prepared 2D-2D hybrid structures of 2D CdSe nanoplatelets (NPLs) with thiol (-SH) functionalized reduced graphene oxide (G-Ph-SH). Microscopic and spectroscopic studies reveal that the G-Ph-SH surface is successfully decorated by CdSe NPLs through a thiophenol (-SH) linker.

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Penile tuberculosis (TB) is an uncommon variety of genitourinary TB. It is either primary (via local spread) or secondary (spread of infection from other organs). We encountered a case of rapidly growing penile ulceration, resembling carcinoma.

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