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1.
Nanotechnology ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38941980

RESUMO

With the increasing demand for sensing platforms operating across UV, visible, and near-infrared wavelengths, nanoporous gold has emerged as an ideal substrate for rapid, quantitative detection of analytes with excellent specificity and high sensitivity. This study investigates thickness-mediated compositional changes and their impact on scattering characteristics of thin nanoporous gold films fabricated using selective chemical etching. Specifically, we observe thickness-induced morphological and structural changes across different fabricated samples from 25-100nm in thickness. Upon their optical characterization across UV-VIS-NIR spectral regime, we notice that the constitutional differences among samples manifest distinctively \& deterministically in their total optical scattering response. In order to gain insights into these observed scattering responses and to fathom the subtle connections between structural properties of NPG films and their optical response, a hybrid theoretical model comprising Maxwell-Garnett \& Bruggeman effective medium approximations has been adopted. Our approach not only allows to appropriately account for the inhomogeneous nature of these films, but also corroborates well with the atomic force microscopy characterizations of the fabricated samples. Furthermore, tracing such a theoretical model is important as it helps in systematically ascertaining additional loss terms emerging in the complex dielectric function of films due to their nanoscale porosity \& roughness, permitting a good reproduction of measured optical spectra. We believe, our approach will not only facilitate accurate regulation of losses in NPG thin films but will also aid in deriving customized optical performance from them, thereby advancing their potential applications in sensing and beyond.

2.
Pharmaceutics ; 16(3)2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38543250

RESUMO

In the field of preparing cosmetic formulations, recent advances recommend the usage of excipients derived from biocompatible materials. In this context, the present study aimed to prepare and characterize the curcumin-loaded Pickering emulsion for possible applications in cosmetic formulation. The coconut oil which is often the component of skin care formulations is used as the oily phase. Curcumin, which is well known for absorbing solar radiation, is expected to work synergistically with coconut oil towards improving the sun protection factor (SPF) of the formulation. Additionally, curcumin can also protect the intracellular components through its well-known antioxidant mechanisms. The Pickering emulsion of coconut oil into water was prepared using the composite colloidal particles derived from ß-carboxymethyl chitosan (CMC) and Gelatin-A (GA) as the emulsifying agent. The reaction conditions in terms of the weight ratios of CMC and GA, the pH of the reaction medium, the oil volume fraction, and the homogenization speed were optimized to obtain the most stable Pickering emulsion. The obtained systems were physico-chemically characterized by dynamic light scattering, zeta potential, optical microscopy, and rheometric measurements. The final CMC-GA-stabilized emulsion demonstrated an oil droplet size of 100 µm and a SPFspectrophotometric (290-320 nm) value of 8.5 at a curcumin loading of 4 mg/mL. Additionally, the final formulation facilitated the uptake of curcumin into fibroblast (WI26) cells under in vitro conditions. Together, the investigation demonstrates a bio-inspired approach to prepare a curcumin-loaded green Pickering emulsion using biocompatible pharmaceutical grade excipients, which may find utility in cosmetic applications.

3.
Sci Rep ; 12(1): 7400, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513498

RESUMO

Explorations into the photonic analogs of topological materials have garnered significant research interest due to their application potential. Particularly in planar systems, the prospects of engendering extinguishable topological states can have wide-ranging implications. With an objective of employing these concepts for thermal emission engineering, here, we design and numerically investigate a quasi-monochromatic highly directional mid-infrared source elicited from inversion symmetry-protected topological interface states. Notably, by relying on the architecture of electro-optic effect-induced topological phase transitions, we introduce the possibility of ultrafast switching of thermal radiation. These reversible phase transitions, being free from carrier transport are inherently fast and evoke thermal emission modulation with a modulation depth upto 0.99. Specifically, our platform exhibits a near-perfect extinguishable spectral emission peak at [Formula: see text]m with a quality factor of over 18500, displaying negligible parasitic emissions. Furthermore, the optimized interface state manifests itself for only one of the polarization modes, resulting in polarized emission under resonance conditions. To establish a methodical approach to parameter optimization, we also model our platform as a leaky mode resonator using the framework of temporal coupled-mode theory. We believe, our findings can provide a way forward in establishing complete control over the optical characteristics of the infrared thermal emitters.

4.
Opt Lett ; 47(7): 1602-1605, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35363688

RESUMO

Fiber Bragg gratings (FBGs) have been advantageously used to improve the chaotic properties of semiconductor lasers. Though these components are known to be highly sensitive to environmental conditions, feedback phase fluctuations are often neglected. In this work, we experimentally demonstrate that the small variations of the propagation time induced by a simple thermal tuning of the FBG are sufficient to induce significant changes of the laser behavior. We report periodic stability enhancements linked with phase variations and highlight that both phase variation and phase offsets play an important role. Last, we show a good qualitative agreement with simulations based on an expanded version of the Lang-Kobayashi model.

5.
J Minim Access Surg ; 17(4): 509-512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34558426

RESUMO

BACKGROUND: To avoid cervical scar in thyroid surgery, various approaches have been proposed. The commonly used approach is combined axillo-breast approach (ABA). However, trans-orovestibular approach (TOVA) is getting popular. The aim of this study is to compare surgical outcomes of patients who underwent endoscopic hemithyroidectomy (EHT) by either ABA or TOVA. PATIENTS AND METHODS: This was a retrospective analysis of clinical data of patients who underwent EHT from January 2013 to December 2018. Patients were divided into two groups: Group A - through ABA and Group B - through TOVA. RESULTS: A total of eighty patients underwent EHT in Group A and 25 in Group B. In both groups, most patients were female (male: female = 1:4.7 in Group A and 1:7.33 in Group B, P = 0.515). In both groups, there was no difference in age (the mean age was 33.44 ± 10.44 years in Group A and 33.04 ± 14.01 years in Group B, P = 0.391) and in size of the nodule (Group A - 3.91 ± 1.17 cm and Group B - 3.6 ± 1.39 cm, P = 0.228). The operating time was significantly less in Group B (Group A - 152.25 ± 30.19 mins and Group B - 126.80 ± 22.94 mins, P ≤ 0.01). The post-operative hospital stay was significantly less in Group B (mean 3.17 ± 0.97 days in Group A and 2.24 ± 0.60 days in Group B, P ≤ 0.01). CONCLUSION: TOVA is associated with shorter operating time and hospital stay with comparable outcomes. Cosmetic outcome is excellent in TOVA, however requires further subjective evaluation.

6.
Indian J Otolaryngol Head Neck Surg ; 73(2): 160-166, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34150590

RESUMO

The transoral vestibular approach (TOVA) is the shortest route for endoscopic thyroidectomy (ET) to approach the thyroid and is a totally scar free procedure, hence it has a clear cosmetic advantage not only over conventional open thyroid surgery but also over other remote access approaches for ET like axilla, breast and chest wall approaches. The aim of this study was to evaluate the feasibility, safety and our initial outcomes of TOVA and highlight the advantages of 3D endoscopic equipment in remote access thyroid surgery. We reviewed our prospectively maintained database who underwent ET. 42 patients who fulfilled the stringent inclusion criteria were offered TOVA. We have used novel Trans-vestibular approach with 3D technology for endoscopic thyroid surgery in all cases. Clinico-demographic profile, investigations, operative details, histopathology and postoperative complications and follow-up data were analyzed by using statistical analysis with SPSS19.00 version. Out of 203 ET operated during study period, 42 (20.69%) patients were operated through TOVA. Hemithyroidectomy were performed in all the patients. There were 3 men and 39 women (M:F = 1:13). Mean tumor size was 3.54 ± 1.17 cm. All patients were euthyroid. All patient had cytological diagnosis of Bethesda category II-IV and all underwent hemithyroidectomy. Mean operation time was 107.71 ± 17.60 min and post-operative length of hospital stay was 2.90 ± 1.28 days. Besides magnification, 3D endoscopy provided excellent depth perception which helped in precise dissection in the restricted space and aided in identification and preservation of the two most vital structures i.e. recurrent laryngeal nerve and parathyroid glands. As most of our patients present with larger goitres, not many patients desirous of ET can be offered TOVA. This novel TOVA has fairly stringent inclusion criteria, however it is the only approach which offers completely scarless endoscopic thyroidectomy and should be offered to eligible patients desirous of ET.

7.
J Cardiothorac Vasc Anesth ; 33(4): 910-917, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30245110

RESUMO

OBJECTIVE: Investigate how a multitude of patient demographics and extracorporeal membranous oxygenation (ECMO)-related complications affect 30-day survival or survival to discharge. DESIGN: Retrospective observational study. SETTING: Urban university hospital, quaternary care center. PARTICIPANTS: Patients who underwent ECMO circulatory support from January 2012 to May 2016. INTERVENTIONS: Date-based data extraction, univariate and multivariate regression analysis. MEASUREMENTS AND MAIN RESULTS: The hospital database contained complete data for 235 adult patients who received venoarterial ECMO (74.04 %) and venovenous ECMO (25.96 %); 106 patients (45.11%) survived. The independent predictors significant in the odds of in-hospital mortality in a multiregression model were age (odds ratio [OR] = 1.028, p = 0.008), extracorporeal cardiopulmonary resuscitation (ECPR) after unsuccessful high-quality CPR (OR = 7.93, p =0.002), cardiogenic shock as the primary indication for circulatory support (OR = 2.58, p = 0.02), acute kidney injury (AKI) before ECMO initiation (OR = 7.53, p < 0.001), time spent on ECMO in days (OR = 1.08, p = 0.03), and limb ischemia (OR = 3.18, p = 0.047). CONCLUSION: The most significant findings of advancing age, time spent on ECMO, AKI, ECMO use in the setting of cardiogenic shock, ECPR, and limb ischemia as a complication of ECMO all independently increase the odds of in-hospital and 30-day mortality. To the best of the authors' knowledge, this study is the first to demonstrate a significant relationship between limb ischemia and mortality.


Assuntos
Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/tendências , Hemofiltração/efeitos adversos , Hemofiltração/tendências , Mortalidade Hospitalar/tendências , Hospitais Urbanos/tendências , Alta do Paciente/tendências , Adulto , Fatores Etários , Idoso , Oxigenação por Membrana Extracorpórea/mortalidade , Feminino , Hemofiltração/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo
8.
J Thyroid Res ; 2018: 4057542, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30370043

RESUMO

Scarless (in the neck) endoscopic thyroidectomy (SET) has evolved into a cosmetically preferred alternative to conventional thyroidectomy (ConT). Recently many of our patients are demanding SET; however their goitres are larger than the recommended size of 4-6 cm. Our aim was to compare the outcomes of ET for small (<6 cm) vs large (≥6 cm) goitres and determine its feasibility in such cases. This is a retrospective analysis of prospectively maintained database of patients undergoing ET. Patients were divided into 2 groups: I, small (<6 cm) and II, large goitres (≥6 cm). Their demographic and clinicopathological profiles, operation time, conversion and complication rates, and hospital stay were compared. 99 patients (101 procedures) were included: group I, 60 patients (61 procedures), and group II, 39 patients (40 procedures). Mean tumor size (± SD) was 4.4 ± 0.9 cm and 6.7 ± 1.1 cm in groups I and II, respectively. The groups were comparable with respect to demographic and clinical profile except for mean duration of goiter [30.1 ± 32.6 months (group I) vs 60.5 ± 102.4 months (group I), p = 0.03] and gland weight [21.5 ± 15.3 grams (group I) vs 62.3 ± 51.3 grams (group II), p = 0.001]. Although there was no significant difference between mean operating times, long term perioperative outcomes, and conversion rates, temporary hypocalcaemia and length of stay were longer in group II. One patient had permanent vocal cord palsy (~1%, 1/101); none had permanent hypoparathyroidism. Our results indicate that ET can be offered to a subset of patients with larger goitres desirous of SET with no significant difference in mean operation time, conversions, and long term postoperative complications in experienced hands.

9.
Bioinformatics ; 32(12): i192-i200, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27307617

RESUMO

MOTIVATION: The alignment of sequencing reads to a transcriptome is a common and important step in many RNA-seq analysis tasks. When aligning RNA-seq reads directly to a transcriptome (as is common in the de novo setting or when a trusted reference annotation is available), care must be taken to report the potentially large number of multi-mapping locations per read. This can pose a substantial computational burden for existing aligners, and can considerably slow downstream analysis. RESULTS: We introduce a novel concept, quasi-mapping, and an efficient algorithm implementing this approach for mapping sequencing reads to a transcriptome. By attempting only to report the potential loci of origin of a sequencing read, and not the base-to-base alignment by which it derives from the reference, RapMap-our tool implementing quasi-mapping-is capable of mapping sequencing reads to a target transcriptome substantially faster than existing alignment tools. The algorithm we use to implement quasi-mapping uses several efficient data structures and takes advantage of the special structure of shared sequence prevalent in transcriptomes to rapidly provide highly-accurate mapping information. We demonstrate how quasi-mapping can be successfully applied to the problems of transcript-level quantification from RNA-seq reads and the clustering of contigs from de novo assembled transcriptomes into biologically meaningful groups. AVAILABILITY AND IMPLEMENTATION: RapMap is implemented in C ++11 and is available as open-source software, under GPL v3, at https://github.com/COMBINE-lab/RapMap CONTACT: rob.patro@cs.stonybrook.edu SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Transcriptoma , Algoritmos , RNA , Análise de Sequência de RNA , Software
10.
Indian J Surg ; 77(Suppl 3): 1318-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27011558

RESUMO

Congenital cystic dilation of the biliary duct is defined as choledochal cyst (CDC). CDC presenting with the classical triad of abdominal pain, lump, and jaundice is seen in only 6 % cases. Cyst excision with hepaticojejunostomy is the standard treatment worldwide. We hereby report five cases of CDC with unusual presentations (gastric outlet obstruction, cyst perforation, giant cystolithiasis, giant cyst, and mixed type) and discuss the challenges faced during the diagnosis and perioperative management of these cases.

11.
J Anaesthesiol Clin Pharmacol ; 30(4): 472-80, 2014 10.
Artigo em Inglês | MEDLINE | ID: mdl-25425769

RESUMO

Hydroxyethyl starch (HES) family has been one of the cornerstones in fluid management for over four decades. Recent evidence from clinical studies and meta-analyses has raised few concerns about the safety of these fluids, especially in certain subpopulations of patients. High-quality clinical trials and meta-analyses have emphasized nephrotoxic effects, increased risk of bleeding, and a trend toward higher mortality in these patients after the use of HES solutions. Scientific evidence was derived from international guidelines, aggregated research literature, and opinion-based evidence was obtained from surveys and other activities (e.g., internet postings). On critical analysis of the current data available, it can be summarized that further large scale trials are still indicated before HES can be discarded.

12.
Ann Coloproctol ; 29(1): 7-11, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23586008

RESUMO

PURPOSE: Perineal transposition of the antropyloric valve following an anorectal excision as a substitute for a permanent colostomy has recently been reported in humans. However, the problem of neural control still remains in these patients. Our aim herein was to study the anatomical feasibility of an anastomosis between the pudendal nerve branches (inferior rectal nerve) innervating the external anal sphincter and the anterior vagal branches of the perineally-transposed antropyloric segment in cadavers. METHODS: The antropyloric segment, along with its carefully dissected branch of the anterior vagus, was mobilized based on the left gastroepiploic pedicle in six fresh human cadavers. The antropyloric valve was then transposed in the perineum after the pudendal nerve branches had been dissected out, and an approximation of these two nerves was performed to ascertain the technical feasibility of their neural anastomosis. RESULTS: The anterior vagus innervating the antropylorus could be harvested in all cadavers below the hepatic division of the main vagus trunk. The inferior rectal nerve or its branches were found consistently around the 3 or the 9 o'clock position in the ischioanal fossa. An anatomical tension-free approximation of the anterior vagus branch (of the transposed antropyloric segment) to the inferior rectal nerve in the perineum was feasible in all the cadavers studied. CONCLUSION: An inferior rectal nerve anastomosis with the anterior vagal branch of the perineally-transposed antropyloric segment can be achieved anatomically. This preliminary step can be the basis for future animal studies and subsequent clinical application of the procedure for possible neural control of the transposed antropyloric segment in the perineum.

13.
Bioresour Technol ; 101(10): 3355-62, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20100656

RESUMO

Hybrid precursor (HP) of silicon and carbon was synthesized from rice hulls by a novel low temperature method, using sol-gel route. The potential of hybrid precursor to remove Zn (II) ions from aqueous solutions was investigated under different experimental conditions. Hybrid precursor removes Zn (II) ions with efficiency higher than 95% at low concentration. The data revealed that initial uptake was rapid and equilibrium was established in 30min. Pseudo first order, Pseudo second order and Intraparticle diffusion kinetic models were applied to the kinetic data and it was found that adsorption process followed pseudo second order with activation energy of 1.093kJmol(-1). Zn (II) removal was quantitatively evaluated using Langmuir and Freundlich isotherm model and monolayer sorption capacity show the value 28.76mg/g indicating the affinity of HP for Zn (II) ions. The negative value of Gibbs free energy obtained in this study with hybrid precursor confirms the feasibility and spontaneous nature of adsorption process.


Assuntos
Carbono/química , Silício/química , Água/química , Zinco/isolamento & purificação , Concentração de Íons de Hidrogênio , Cinética , Soluções , Termodinâmica
14.
J Hazard Mater ; 163(2-3): 1194-8, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18774221

RESUMO

Use of low-cost hybrid precursor, prepared from rice hull has been studied as a sorbent for the removal of Pb(2+) from aqueous solutions. Effect of contact time, initial concentration, pH and temperature has been studied. The effect of temperature (30, 40, 50 and 60 degrees C) on adsorption phenomena has been studied and data have been analyzed using Langmuir isotherm. The change in enthalpy (Delta H) (-14.6179 kJ/mol), free energy (Delta G) and entropy (DeltaS) has also been evaluated. The negative values of Delta G and Delta H indicate the adsorption of lead ions on the surface of hybrid precursor to be spontaneous and exothermic under the experimental condition.


Assuntos
Chumbo/isolamento & purificação , Oryza , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Soluções , Temperatura , Termodinâmica , Fatores de Tempo
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