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1.
Opt Lett ; 38(8): 1253-5, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23595449

RESUMO

We have demonstrated ultrafast direct soft x-ray microscopy imaging. Microscopy images were acquired using an objective zone plate and a single strong high harmonic burst generated from He in a two-color laser field. This zone-plate-based microscopy system delivered real-space images directly without any data processing. The spatial resolution of the microscope was estimated to be about 140 nm from the image of nanoscale grating patterns.

2.
Appl Opt ; 52(8): 1725-30, 2013 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-23478778

RESUMO

An UV cleaning technique has been used for the removal of carbon contamination from grating surface, using oxygen free-radicals generated by the absorption of UV radiation (172 nm) in atmospheric oxygen. The extent of restoration of absolute diffraction efficiency (ADE) and grating blaze angle of a carbon-contaminated variable line-spaced concave grating (average line spacing of 1200 lines/mm, blaze angle 3.2 deg, and blaze wavelength 10 nm) has been studied over a 5-70 nm wavelength range. The contamination (due to prolonged use in extreme-ultraviolet spectrograph) resulted in a drastic reduction in the diffraction efficiency of grating, along with a change in the blaze angle. The UV cleaning led to the restoration of blaze angle as well as to an increase in the ADE by more than an order of magnitude for the first two diffraction orders (i.e., from ~0.2 to ~7.2%) for the first diffraction order and 0.1 to ~5% for the second diffraction order at the blaze wavelength. The study is useful for the restoration of carbon-contaminated costly optics.

3.
Appl Spectrosc ; 72(9): 1416-1424, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29714080

RESUMO

An experimental study has been carried out to characterize and investigate the performance of a flat-field grating spectrograph (FFGS) for higher diffraction order in the wavelength range of 80-170 Å. An aberration-corrected, mechanically ruled spherical grating with variable line spacing was used as a dispersive element in the spectrograph. The study was carried out using high-order harmonic radiation generated by an interaction of Ti:sapphire laser pulses with inert gas-filled cells. It was observed that the fraction of photons diffracted in the second diffraction order to that of the first order is as high as ∼ 65% at ∼ 80 Å wavelength, which reduces to ∼ 15% at ∼ 150 Å, whereas for the third diffraction order, the fraction was substantially lower, ∼ 15% at ∼ 100 Å. The observed results match well with reflectivity calculated using REFLEC software and also with the measurement carried out using INDUS-1 reflectivity beamline at RRCAT, Indore. The use of a high-order harmonic source for the study is advantageous, as the higher diffraction order contribution can be estimated from a single spectral image, which can be recorded in a single laser shot. The study will be useful for estimation of conversion efficiency-photon flux of a source using a variable line spaced (VLS) grating based spectrograph/monochromator.

4.
J Hum Reprod Sci ; 10(2): 119-123, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28904501

RESUMO

AIM: The aim of the study was to measure patient's satisfaction level and acceptance of conscious sedation as a method of pain relief following transvaginal oocyte retrieval (TVOR) during assisted reproduction technology treatment. We also evaluated the factors that may influence the efficacy of conscious sedation method. SETTING AND DESIGN: A prospective cross-sectional study. MATERIALS AND METHODS: Prospective study was conducted from October 2015 to January 2016 at a university-level hospital and 100 women were recruited. Variables for analysis included woman age, duration of procedure, number of oocytes retrieved, and transmyometrial passage of the needle. Pain assessment was done by visual analog scale (VAS). Medical complications, and patient satisfaction score [Likert's score and client satisfaction questionnaire (CSQ)] were recorded. RESULTS: There was a moderate positive correlation between age and pain score on day 1 post-procedure. When the duration of procedure was >12 min, immediate post-procedure pain score was significantly higher compared to those whose procedure where duration was <12 min. There was no correlation between pain score and the number of oocytes retrieved (≤5, 6-15, and ≥16) and transmyometrial passage of needle. The VAS 10-point score immediately post-procedure, after 6 and 24 h post-procedure, and on day of embryo transfer was 2.83 (±1.67), 0.78 (±1.04), 0.39 (±1.09), and 0.14 (±0.58), respectively. The Likert's score was 3.65 (±0.82) and mean CSQ was 27.04 (±3.01). Majority of the women (86%) preferred the same pain relief method for future analgesia. There were no major complications. CONCLUSION: Conscious sedation was associated with high satisfaction level and acceptance rate among patients undergoing TVOR.

5.
Eur J Obstet Gynecol Reprod Biol ; 214: 109-114, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28511086

RESUMO

OBJECTIVE: To evaluate the effectiveness of local endometrial injury in women undergoing in vitro fertilization (IVF) with at least one previous unsuccessful attempt. STUDY DESIGN: Randomized controlled trial. Recruited women were randomized into two groups. In group A (pipelle group), women underwent pipelle biopsy twice in the luteal phase in the cycle prior to IVF. In group B (control), women did not undergo any intervention prior to IVF. The primary outcome was clinical pregnancy rate. The secondary outcomes included live birth, miscarriage, multiple pregnancy and preterm delivery rates. RESULTS: One hundred and eleven women were included in the study with 55 in the pipelle group and 56 in the control arm. The baseline clinical characteristics were similar in both groups. The clinical pregnancy rates were not significantly different between pipelle and control group (34.09% vs. 27.65%; Odds ratio, OR 1.35, 95% confidence interval, CI 0.55-3.30). The live birth (31.81% vs. 25.53%; OR 1.36, 95% CI 0.55-3.39), multiple pregnancy (33.33% vs. 61.54%; OR 0.31, 95% CI 0.07-1.47), miscarriage (6.66% vs. 7.69%; OR 0.86, 95% CI 0.05-15.23) and preterm delivery rates (35.71% vs. 66.66%; OR 0.28, 95% CI 0.05-1.4) were also not significantly different between the two groups. CONCLUSION: Current study did not find any improvement in IVF success rates following endometrial injury in woman undergoing IVF after previous failed attempt.


Assuntos
Endométrio/lesões , Taxa de Gravidez , Técnicas de Reprodução Assistida , Adulto , Feminino , Humanos , Gravidez
6.
Int J Trichology ; 3(1): 20-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21769231

RESUMO

BACKGROUND: Alopecia areata (AA) is a common, non-scarring, patchy loss of hair at scalp and elsewhere. Its pathogenesis is uncertain; however, auto-immunity has been exemplified in various studies. Familial incidence of AA is 10-42%, but in monozygotic twins is 50%. Local steroids (topical / intra-lesional) are very effective in treatment of localized AA. AIM: To compare hair regrowth and side effects of topical betamethasone valerate foam, intralesional triamcinolone acetonide and tacrolimus ointment in management of localized AA. MATERIALS AND METHODS: 105 patients of localized AA were initially registered but 27 were drop out. So, 78 patients allocated at random in group A (28), B (25) and C (25) were prescribed topical betamethasone valerate foam (0.1%) twice daily, intralesional triamcinolone acetonide (10mg/ml) every 3 weeks and tacrolimus ointment (0.1%) twice daily, respectively, for 12 weeks. They were followed for next12 weeks. Hair re-growth was calculated using "HRG Scale"; scale I- (0-25%), S II-(26-50%), S III - (51-75%) and S IV- (75-100%). RESULTS: Hair re-growth started by 3 weeks in group B (Scale I: P<0.03), turned satisfactory at 6 weeks in group A and B (Scale I: P<0.005, Scale IV: P<0.001)), good at 9 weeks (Scale I: P<0.0005, Scale IV: P<0.00015), and better by 12 weeks of treatment (Scale I: P<0.000021, Scale IV: P<0.000009) in both A and B groups. At the end of 12 weeks follow-up hair re-growth (>75%, HRG IV) was the best in group B (15 of 25, 60%), followed by A (15 of 28, 53.6%) and lastly group-C (Nil of 25, 0%) patients. Few patients reported mild pain and atrophy at injection sites, pruritus and burning with betamethasone valerate foam and tacrolimus. CONCLUSION: Intralesional triamcinolone acetonide is the best, betamethasone valerate foam is better than tacrolimus in management of localized AA.

9.
Opt Lett ; 32(1): 65-7, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17167585

RESUMO

Strong intensity enhancement or extinction of some single harmonics is observed in high-harmonic generation from 48 fs Ti:sapphire laser pulses propagating through preformed low-excited laser-produced plasmas of various materials (GaAs, Cr, InSb, stainless steel). The intensities of some of the harmonics in the mid- and end-plateau regions vary from ~23-fold enhancement to near disappearance compared with those of the neighboring ones. It is also shown that the observed intensity enhancement (or extinction) can be varied by controlling the chirp of the driving laser radiation.

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