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1.
Opt Lett ; 47(22): 5993-5996, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37219155

RESUMO

We show a noise self-canceling real-time picometer scale interferometer by exploiting the unique spiral phase structure of twisted light. We use a single cylindrical interference-lens to implement the twisted interferometer and perform simultaneous measurement on N phase-orthogonal single-pixel intensity pairs chosen on the petal of the daisy-flower-like interference pattern. A cancellation of various noises by three orders of magnitude was achieved in our setup compared with a conventional single-pixel detection, enabling a sub-100 picometer resolution in measuring a non-repetitive intracavity dynamic event in real-time. Furthermore, the noise cancellation capability of the twisted interferometer scales up statistically for higher radial and azimuthal quantum numbers of the twisted light. The proposed scheme could find applications in precision metrology and in developing analogous ideas for twisted acoustic beam, electron beams, and matter waves.

2.
Mol Phylogenet Evol ; 159: 107101, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33592235

RESUMO

ECERIFERUM1 (CER1) and ECERIFERUM3 (CER3) are key genes in synthesis of alkanes, a major component of cuticular waxes in land plants. The genes share extensive similarity, including the N-terminal (ERG3/FAH) and C-terminal (WAX2) domains. This study, traces the origin, evolutionary history, phylogenetic relationships and variation in copy number of the two genes within and beyond the Viridiplantae (green plants). Protein homologs of both CER1 and CER3 were identified across most Embryophyta (land plants), a single homolog (CER1/3) in charophytes and prasinophytes, and none in the other green, red or brown algae. Ancestral state reconstructions in 100 sequenced Archaeplastida using presence/absence of CER1/3 family genes revealed that the CER1/3 gene probably originated in the common ancestor of Viridiplantae. Phylogenetic analysis of CER1 and CER3 protein sequences from 146 plant species strongly suggests that the two genes originated by duplication of CER1/3 in the ancestral embryophyte. The evolution of CER1 and CER3 genes involved differential divergence of the two domains. Outside Embryophyta, CER1/3 similar sequences identified in diatoms and a cryptophyte, were the closest relatives of the CER1/3 family proteins. Proteins harbouring WAX2-wxAR (WAX2 associated region) similar regions were identified in proteins of bacteria, Archaea, cryptophytes, dinoflagellates and Stramenopiles. The independent existence of both ERG3/FAH and WAX2-wxAR domains in diverse lineages strongly points to the origin of CER1/3 gene in green plants by the fusion of pre-existing domains.


Assuntos
Carbono-Carbono Liases/genética , Embriófitas/genética , Evolução Molecular , Filogenia , Proteínas de Plantas/genética , Alcanos/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis , Regulação da Expressão Gênica de Plantas , Ceras/metabolismo
3.
Sci Rep ; 11(1): 14365, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34257351

RESUMO

Although, many conventional approaches have been used to measure viscosity of fluids, most methods do not allow non-contact, rapid measurements on small sample volume and have universal applicability to all fluids. Here, we demonstrate a simple yet universal viscometer, as proposed by Stokes more than a century ago, exploiting damping of capillary waves generated electrically and probed optically with sub-nanoscale precision. Using a low electric field local actuation of fluids we generate quasi-monochromatic propagating capillary waves and employ a pair of single-lens based compact interferometers to measure attenuation of capillary waves in real-time. Our setup allows rapid measurement of viscosity of a wide variety of polar, non-polar, transparent, opaque, thin or thick fluids having viscosity values varying over four orders of magnitude from [Formula: see text]. Furthermore, we discuss two additional damping mechanisms for nanomechanical capillary waves caused by bottom friction and top nano-layer appearing in micro-litre droplets. Such self-stabilized droplets when coupled with precision interferometers form interesting microscopic platform for picomechanical optofluidics for fundamental, industrial and medical applications.

4.
Crit Rev Ther Drug Carrier Syst ; 36(2): 137-181, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30806211

RESUMO

The parenteral route of administration is preferred over the oral route for treatment of many chronic and life-threatening diseases due to better patient compliance. Long-acting injectables/depot delivery systems are formulations intended for prolonged/sustained drug release over a long period of time ranging from a few days to months. Depot delivery systems enhance product quality by decreasing dosing frequency, simplifying the drug regimen. Parenteral depots reduce the relapse rate of disease and the maintenance phase of therapy, hence improving efficacy and treatment adherence. However, despite being extensively explored in the last seventy years, only a few depot products have been marketed or have reached commercial viability. The introduction of long-acting injectables of any drug took 9 to 10 years after approval of its oral formulation. Mainly the market has been conquered by long-acting injectables for antipsychotic, substance abuse, and hormonal therapy drugs. This article focuses on the preparation of long-acting injectables with special emphasis on challenges associated with formulation. The evolution and current global market trend of various depot formulations are also discussed. Insight is provided into the promising future of long-acting injectables of protein-based drugs as well as multidrug therapy, along with potential uses in the treatment of chronic diseases like HIV, Parkinson's, and Alzheimer's.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética , Injeções/tendências , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacocinética , Antipsicóticos/administração & dosagem , Antipsicóticos/farmacocinética , Previsões , Terapia de Reposição Hormonal/métodos , Terapia de Reposição Hormonal/tendências , Humanos , Imunoterapia Adotiva/métodos , Imunoterapia Adotiva/tendências , Injeções/métodos
5.
Sci Rep ; 7: 42554, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28198468

RESUMO

Precision measurement on momentum transfer between light and fluid interface has many implications including resolving the intriguing nature of photons momentum in a medium. For example, the existence of Abraham pressure of light under specific experimental configuration and the predictions of Chau-Amperian formalism of optical momentum for TE and TM polarizations remain untested. Here, we quantitatively and cleanly measure nanomehanical dynamics of water surface excited by radiation pressure of a laser beam. We systematically scanned wide range of experimental parameters including long exposure times, angle of incidence, spot size and laser polarization, and used two independent pump-probe techniques to validate a nano- bump on the water surface under all the tested conditions, in quantitative agreement with the Minkowski's momentum of light. With careful experiments, we demonstrate advantages and limitations of nanometer resolved optical probing techniques and narrow down actual manifestation of optical momentum in a medium.

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