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1.
Article de Anglais | MEDLINE | ID: mdl-38048181

RÉSUMÉ

Electrochromic windows have gained growing interest for their ability to change their optical state in the visible and NIR ranges with minimal input power, making them energy-efficient. However, material processing costs, fabrication complexity, and poor electrochromic properties can be barriers to the widespread adoption of this technology. To address these issues, electrochromic material and fabrication processes are designed to realize their potential as a cost-effective and energy-efficient technology. In this work, an electrochromic composite material-based ink is synthesized consisting of WO3·H2O nanoplates supported on rGO (reduced graphene oxide) nanosheets (WH-rGO), wherein an optimized amount of rGO (0.05 to 0.5 wt %) is introduced for providing a higher conduction pathway for efficient charge transport without sacrificing the electrochromic performance of WO3·H2O nanoplates. The stable ink dispersion prepared in the study is deposited by spray coating on transparent conducting electrodes over large areas (25 cm2). The WH-rGO nanocomposite (0.4 wt %) results in 43% optical modulation at 700 nm, with bleaching and coloration times of 6 and 8 s, respectively. Interestingly, the device also possesses an electrochemical energy storage capability with an areal capacitance of 16.3 mF/cm2. The electrochromic composite material is successfully translated on tin doped indium oxide (ITO)-coated Al metal mesh hybrid electrodes (T = 80%, Rs = 40 Ω/□) to replace ITO. Finally, an electrochromic device of 5 × 5 cm2 is fabricated by spray-coating the ink on cost-effective ITO/Al-mesh hybrid electrodes. The device displays blue to colorless modulation with an excellent bleaching time of 0.43 s and a coloration time of 2.16 s, making it one among the fast-operating devices fabricated by complete solution processing. This work showcases the economical production of a dual-function electrochromic device, which can be a feasible option as an alternative to existing ITO-based devices in both automotive and infrastructure applications.

2.
Transl Psychiatry ; 11(1): 138, 2021 02 24.
Article de Anglais | MEDLINE | ID: mdl-33627624

RÉSUMÉ

Recent clinical trials of transcranial direct current stimulation (tDCS) in depression have shown contrasting results. Consequently, we used in-vivo neuroimaging to confirm targeting and modulation of depression-relevant neural circuitry by tDCS. Depressed participants (N = 66, Baseline Hamilton Depression Rating Scale (HDRS) 17-item scores ≥14 and <24) were randomized into Active/Sham and High-definition (HD)/Conventional (Conv) tDCS groups using a double-blind, parallel design, and received tDCS individually targeted at the left dorsolateral prefrontal cortex (DLPFC). In accordance with Ampere's Law, tDCS currents were hypothesized to induce magnetic fields at the stimulation-target, measured in real-time using dual-echo echo-planar-imaging (DE-EPI) MRI. Additionally, the tDCS treatment trial (consisting of 12 daily 20-min sessions) was hypothesized to induce cerebral blood flow (CBF) changes post-treatment at the DLPFC target and in the reciprocally connected anterior cingulate cortex (ACC), measured using pseudo-continuous arterial spin labeling (pCASL) MRI. Significant tDCS current-induced magnetic fields were observed at the left DLPFC target for both active stimulation montages (Brodmann's area (BA) 46: pHD = 0.048, Cohen's dHD = 0.73; pConv = 0.018, dConv = 0.86; BA 9: pHD = 0.011, dHD = 0.92; pConv = 0.022, dConv = 0.83). Significant longitudinal CBF increases were observed (a) at the left DLPFC stimulation-target for both active montages (pHD = 3.5E-3, dHD = 0.98; pConv = 2.8E-3, dConv = 1.08), and (b) at ACC for the HD-montage only (pHD = 2.4E-3, dHD = 1.06; pConv = 0.075, dConv = 0.64). These results confirm that tDCS-treatment (a) engages the stimulation-target, and (b) modulates depression-relevant neural circuitry in depressed participants, with stronger network-modulations induced by the HD-montage. Although not primary outcomes, active HD-tDCS showed significant improvements of anhedonia relative to sham, though HDRS scores did not differ significantly between montages post-treatment.


Sujet(s)
Stimulation transcrânienne par courant continu , Dépression , Méthode en double aveugle , Humains , Imagerie par résonance magnétique , Cortex préfrontal/imagerie diagnostique
3.
Braz J Infect Dis ; 17(3): 369-74, 2013.
Article de Anglais | MEDLINE | ID: mdl-23602467

RÉSUMÉ

Hepatitis C virus infects over 15 million patients from India and 2.86 million from Brazil. Detection of anti-hepatitis C virus antibodies has limited sensitivity during acute phase: the pre-seroconversion window period. Hepatitis C virus-RNA detection techniques are used to overcome this shortfall, but are costly and unavailable widely in developing countries. Estimation of hepatitis C virus core-antigen, a protein with highly conserved sequence, by enzyme-immunoassays is an economic and simpler alternative to RNA detection. This study was conducted in Delhi, involving 300 acute and chronic liver disease patients, tested for anti-hepatitis C virus 3rd-generation ELISA, hepatitis C virus core-antigen-ELISA and hepatitis C virus-RNA reverse transcription-polymerase chain reaction. Among the acute patients, hepatitis C virus core-antigen assay could identify 13 out of 14 pre-seroconversion window period cases and 6 out of 8 seroconverted cases, with a pre-seroconversion window period sensitivity of 92.9% and specificity of 100%. In hepatitis C virus core-antigen-positive cases, the viral load was in the range of 4900 to 1.46×10(6)IU/mL, whereas in hepatitis C virus core-antigen-negative cases, the range of viral load was 100-4500IU/mL. The cost of the hepatitis C virus core-antigen-ELISA was estimated around 3-4 times lesser than the in-house reverse transcription-polymerase chain reaction and 9-10 times lesser than the United States Food and Drug Administration approved reverse transcription-polymerase chain reaction. With a good sensitivity and specificity in the acute phase of infection, hepatitis C virus core-antigen-ELISA can thus be a useful alternative in the developing nations.


Sujet(s)
Hepacivirus , Antigènes de l'hépatite C/sang , Hépatite C/diagnostic , ARN viral/sang , Protéines du core viral/sang , Hepacivirus/génétique , Hepacivirus/immunologie , Humains , Inde , Valeur prédictive des tests , Reproductibilité des résultats , RT-PCR , Sensibilité et spécificité , Charge virale
4.
J Agric Food Chem ; 58(22): 11626-32, 2010 Nov 24.
Article de Anglais | MEDLINE | ID: mdl-20964435

RÉSUMÉ

Glucosinolate composition was determined in wild radish accessions from eight states in the northeastern and southern United States to determine the variability of production among accessions. Glucosinolates were evaluated from roots, leaves, flowers, primary, and secondary branches. Seventeen glucosinolates were identified, with glucoerucin, glucoraphenin, glucobrassicin, and gluconasturtiin contributing 90% to 100% of the total glucosinolates. Flowers contained the highest glucosinolate concentrations, 12.07 to 55.36 µmol/g, but flowers contributed only 5.3 to 21.3% to the total glucosinolates. Of the eight accessions, the Mississippi accession produced significantly higher levels of total glucosinolates and glucosinolates which can be degraded to isothiocyanates per plant, totals of 618.97 and 563.53 µmol/plant, respectively. Total plant biomass did not differ between accessions indicating a difference in the ability of the Mississippi accession to produce glucosinolates. Further studies are needed to determine if this accession would consistently produce higher glucosinolate levels under different environmental conditions.


Sujet(s)
Glucosinolates/analyse , Extraits de plantes/analyse , Raphanus/composition chimique , Glucosinolates/métabolisme , Extraits de plantes/métabolisme , Raphanus/métabolisme
5.
J Agric Food Chem ; 58(6): 3309-15, 2010 Mar 24.
Article de Anglais | MEDLINE | ID: mdl-20163113

RÉSUMÉ

Wild radish (Raphanus raphanistrum L.) produces glucosinolates (GSL), which are important for its use as a biofumigation or allelopathic plant for weed management. Total GSL concentrations and individual GSLs were quantified in different plant parts at different developmental stages. Eight GSLs were found in various plant tissues but glucoerucin, glucoraphenin, and glucotropaeolin comprised >90% of the total GSLs. All three are degraded to isothiocyanates, which are associated with weed suppression. Maximum GSL concentration (1942.2 micromol/plant) occurred at 50% flowering stage prior to the time of maximum biomass production, when GSL concentration was 1246.65 mumol/plant. Roots contributed <15% of the total GSL. The highest concentration of GSLs was in flowers at flowering stage, but due to the low biomass they contributed only 11.83% to the total GSL. On the basis of these results, wild radish should be incorporated into soil at 50% flowering to provide the most GSLs for weed suppression.


Sujet(s)
Glucosinolates/analyse , Extraits de plantes/analyse , Raphanus/composition chimique , Raphanus/croissance et développement
6.
BMC Ophthalmol ; 6: 19, 2006 Apr 28.
Article de Anglais | MEDLINE | ID: mdl-16646976

RÉSUMÉ

BACKGROUND: Diffuse lamellar keratitis (DLK) is a relatively new syndrome that is increasingly being reported after LASIK. We have observed that a hyperopic shift may be associated with the occurrence of this diffuse lamellar keratitis. CASE PRESENTATION: A 26 year old man developed bilateral diffuse lamellar keratitis (DLK) following myopic LASIK. The residual refractive error was +0.5D OD and +0.25D OS at the end of the first week. The sterile infiltrates resolved over a period of 4-6 weeks on topical steroid therapy. A progressive hyperopic shift was noted in the right eye with an error +4.25Dsph/+0.25Dcyl 20 at the final follow up 6 months post surgery. CONCLUSION: Diffuse lamellar keratitis after LASIK may be associated with a significant hyperopic shift.


Sujet(s)
Hypermétropie/étiologie , Kératite/étiologie , Kératomileusis in situ avec laser excimère/effets indésirables , Adulte , Évolution de la maladie , Humains , Hypermétropie/physiopathologie , Mâle , Myopie/chirurgie , Facteurs temps
7.
J Cataract Refract Surg ; 30(2): 326-33, 2004 Feb.
Article de Anglais | MEDLINE | ID: mdl-15030820

RÉSUMÉ

PURPOSE: To compare the safety and efficacy of trypan blue 0.1%, gentian violet 0.001%, indocyanine green 0.5% (ICG), fluorescein 2%, and the patient's autologous blood for anterior capsule staining in cases of white cataract. SETTING: Rajendra Prasad Center for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India. METHODS: Fifty eyes of 50 patients with age-related white cataract had anterior capsule staining with trypan blue, ICG, or gentian violet under an air bubble or subcapsularly with fluorescein or autologous blood followed by phacoemulsification with foldable intraocular lens implantation. Each stain was used in 10 eyes. The ease of creating a continuous curvilinear capsulorhexis (CCC) and the complications during the surgery were noted. Postoperative examinations at 6 hours, 1 day, 1 week, and 1 month included slitlamp microscopy, uncorrected visual acuity, and best corrected visual acuity (BCVA). The staining patterns on the anterior capsule, side port, corneal tunnel, and anterior cortex were assessed intraoperatively and within 6 hours and at 1 day. The intraocular pressure (IOP) was assessed at 1 day; pachymetry, at 1 day and 1 month; and the endothelial cell count, at 1 month. RESULTS: The surgeon had best visualization during the anterior capsulorhexis with trypan blue, ICG, and gentian violet, and a complete CCC was achieved in all eyes in the 3 groups. Two eyes each in the fluorescein and autologous blood groups had extension of the CCC so that the capsulorhexis was complete but not curvilinear. Anterior capsule fibrosis was detected with trypan blue (1 eye) and ICG (2 eyes). The anterior vitreous was stained with fluorescein in 2 eyes. All eyes achieved a BCVA of 20/30 or better from 1 week postoperatively to the last follow-up. The side port and corneal tunnel were stained most intensely with gentian violet followed by trypan blue and ICG and less intensely with fluorescein and autologous blood. The IOP, pachymetry, and endothelial cell loss were comparable between the stains. CONCLUSION: Although trypan blue, ICG, gentian violet, fluorescein, and autologous blood were safely used to stain the anterior capsule for phacoemulsification in eyes with white cataract, trypan blue, ICG, and gentian violet were more effective in staining the capsule.


Sujet(s)
Capsulorhexis/méthodes , Cataracte/diagnostic , Agents colorants , Capsule du cristallin/anatomopathologie , Coloration et marquage/méthodes , Pôle antérieur du bulbe oculaire , Sang , Numération cellulaire , Fluorescéine , Chlorure de méthylrosanilinium , Humains , Vert indocyanine , Pression intraoculaire , Complications peropératoires , Capsule du cristallin/chirurgie , Adulte d'âge moyen , Phacoémulsification/méthodes , Complications postopératoires , Sécurité , Bleu de trypan , Acuité visuelle
8.
Ophthalmic Surg Lasers Imaging ; 34(6): 470-1, 2003.
Article de Anglais | MEDLINE | ID: mdl-14620751

RÉSUMÉ

A 9-year-old girl with refractory glaucoma with an anterior chamber intraocular lens underwent transscleral contact diode laser cyclophotocoagulation. Slit-lamp examination and ultrasound biomicroscopy revealed iris retraction and retroflexion at 2 weeks of follow-up. The probable cause of this complication is discussed.


Sujet(s)
Corps ciliaire/chirurgie , Glaucome/chirurgie , Maladies de l'iris/étiologie , Coagulation par laser/effets indésirables , Chambre antérieure du bulbe oculaire/chirurgie , Enfant , Ablation de dispositif , Femelle , Gonioscopie , Humains , Pression intraoculaire , Maladies de l'iris/imagerie diagnostique , Pose d'implant intraoculaire , Lentilles intraoculaires , Sclère , Échographie , Vitrectomie
11.
Ophthalmic Surg Lasers Imaging ; 34(2): 100-3, 2003.
Article de Anglais | MEDLINE | ID: mdl-12665224

RÉSUMÉ

BACKGROUND AND OBJECTIVE: To record the surgical peculiarities during phacoemulsification in patients with type II diabetes. PATIENTS AND METHODS: A retrospective, noncomparative analysis. Data from 58 eyes of 43 patients having significant cataract with type II diabetes of more than 5 years' duration who underwent phacoemulsification were considered. Intraoperative difficulties and complications were noted and analyzed. RESULTS: In 24.13% (n = 14) of the cases, the nucleus could not be divided after initial trenching. The management of the nucleus and the cortex required modifications in the surgical technique. CONCLUSIONS: Type II diabetic cataracts were sticky and leathery in approximately one-quarter of the cases.


Sujet(s)
Cataracte/étiologie , Diabète de type 2/complications , Complications peropératoires , Phacoémulsification , Complications postopératoires , Résines acryliques , Femelle , Humains , Pose d'implant intraoculaire , Lentilles intraoculaires , Mâle , Adulte d'âge moyen , Études rétrospectives
12.
J Cataract Refract Surg ; 29(4): 845-7, 2003 Apr.
Article de Anglais | MEDLINE | ID: mdl-12686261

RÉSUMÉ

Phacoemulsification with implantation of an acrylic foldable intraocular lens in a 14-year-old girl with microspherophakia is described. The associated lenticular myopia was disabling in terms of quality of life. With the help of nylon iris hooks, the procedure was uneventful and the outcome successful


Sujet(s)
Maladies héréditaires de l'oeil/chirurgie , Maladies du cristallin/chirurgie , Pose d'implant intraoculaire , Myopie/chirurgie , Phacoémulsification/méthodes , Résines acryliques , Adolescent , Femelle , Humains , Lentilles intraoculaires , Acuité visuelle
13.
J Cataract Refract Surg ; 29(3): 435-6, 2003 Mar.
Article de Anglais | MEDLINE | ID: mdl-12663002

RÉSUMÉ

We describe a technique of capsule staining called capsule painting. Using a Khokhar capsule painting cannula, the dye is spread directly over the anterior capsule but to no other part of the anterior chamber. There is minimal turbulence in the anterior chamber as there is no need to replace the injected viscoelastic material. The use of minimal dye and viscoelastic material reduces the cost of surgery.


Sujet(s)
Capsulorhexis/méthodes , Agents colorants/administration et posologie , Capsule du cristallin/chirurgie , Coloration et marquage/méthodes , Cathétérisme/méthodes , Humains , Vert indocyanine/administration et posologie , Bleu de trypan/administration et posologie
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