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1.
Anaesthesia ; 78(4): 442-448, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599621

RESUMO

Erector spinae plane block and paravertebral block can provide analgesia for abdominal surgery. It is unclear whether erector spinae block is inferior to paravertebral block. We aimed to determine whether sufentanil dose and pain intensity (11-point scale) to 24 h after erector spinae block exceeded those after paravertebral block by no more than 5 µg and 1 point, respectively. We randomly allocated 166 adults to 0.4 ml.kg-1 ropivacaine 0.375% before scheduled laparoscopic nephroureterectomy, 83 each to erector spinae or paravertebral injection. We measured incision pain and intra-abdominal pain at rest and on movement 0.5 h, 2 h, 6 h, 18 h, 24 h and 48 h after surgery. Median (IQR [range]) cumulative sufentanil dose after erector spinae block was 15 (5-30 [0-105]) µg vs. 20 (10-50 [0-145]) µg after paravertebral block, median (95%CI) difference 5 µg (0-10), erector spinae non-inferiority p < 0.001. Median (IQR [range]) pain were 1.5 (1.0-2.0 [0.0-5.3]) after erector spinae block vs. 2.0 (1.0-2.5 [0.0-6.0]) after paravertebral block, median (95% CI) difference 0.3 (0.0-0.5), erector spinae non-inferiority p < 0.001. Adverse events did not differ between groups. Erector spinae block analgesia was not inferior to paravertebral block analgesia after laparoscopic nephroureterectomy.


Assuntos
Laparoscopia , Bloqueio Nervoso , Adulto , Humanos , Nefroureterectomia , Sufentanil , Dor Pós-Operatória/prevenção & controle
2.
Phys Rev Lett ; 126(21): 214801, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34114880

RESUMO

A simple, efficient scheme was developed to obtain near-gigaelectronvolt electron beams with energy spreads of few per-mille level in a single-stage laser wakefield accelerator. Longitudinal plasma density was tailored to control relativistic laser-beam evolution, resulting in injection, dechirping, and a quasi-phase-stable acceleration. With this scheme, electron beams with peak energies of 780-840 MeV, rms energy spreads of 2.4‰-4.1‰, charges of 8.5-23.6 pC, and rms divergences of 0.1-0.4 mrad were experimentally obtained. Quasi-three-dimensional particle-in-cell simulations agreed well with the experimental results. The dechirping strength was estimated to reach up to 11 TeV/mm/m, which is higher than previously obtained results. Such high-quality electron beams will boost the development of compact intense coherent radiation sources and x-ray free-electron lasers.

3.
Opt Lett ; 45(18): 5081-5084, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32932458

RESUMO

Accurate and fast characterization of spatio-temporal information of high-intensity, ultrashort pulses is crucial in the field of strong-field laser science and technology. While conventional self-referenced interferometers were widely used to retrieve the spatial profile of the relative spectral phase of pulses, additional measurements of temporal and spectral information at a particular position of the laser beam, however, were necessary to remove the indeterminacy, which increases the system complexity. Here we report an advanced, dual-functional interferometer that is able to reconstruct the complete spatio-temporal information of ultrashort pulses with a single scan of the interferometer arm. The setup integrates an interferometric frequency-resolved optical gating (FROG) with a radial shearing Michelson interferometer. Through scanning one arm of the interferometer, both the cross-correlated FROG trace at the central part of the laser beam and the delay-dependent interferograms of the entire laser profile are simultaneously obtained, allowing a fast three-dimensional reconstruction of few-cycle laser pulses.

4.
Phys Rev Lett ; 125(3): 034801, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32745390

RESUMO

In order to address the present difficulty in experimentally generating the relativistic Laguerre-Gaussian laser, primarily due to damage caused to optical modulators, a high-reflectivity phase mirror is applied in the femtosecond petawatt laser system to generate a relativistic hollow laser at the highest intensity of 6.3×10^{19} W/cm^{2} for the first time. A simple optical model is used to verify that the vortex laser may be generated in this new scheme; using such a relativistic vortex laser, the hollow plasma drill and acceleration are achieved experimentally and proven by particle-in-cell simulations. With the development of the petawatt laser, this scheme opens up possibilities for the convenient production of the relativistic hollow laser at high repetition and possible hollow plasma acceleration, which is important for a wide range of applications such as the generation of radiation sources with orbital angular momentum, fast ignition for inertial confinement fusion, and jet research in the astrophysical environment.

5.
Phys Rev Lett ; 122(2): 024801, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30720300

RESUMO

A new relativistic vortex cutter driven by the Laguerre-Gaussian (LG) mode is carried out for the first time in three-dimensional particle-in-cell simulations. Studies show that the electric fields periodically concentrate and emanate within every laser wavelength for the reflected circularly polarized LG_{p}^{l} (p=0, l=1, σ_{z}=-1) laser, which works just like a vortex cutter, resulting in a relativistic ultrashort collimated electron cluster with a constant period in space. A single particle model is given and verifies that the cluster formation has a close relation with the parameters of orbital angular momentum (l) and spin angular momentum (σ_{z}). Such a relativistic vortex cutter potentially can be applied for the accelerator, generating high-flux particle and coherent radiation sources, and so on.

6.
Colorectal Dis ; 21(1): 30-37, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30184334

RESUMO

AIM: Published outcomes following ligation of the intersphincteric fistula tract (LIFT) for high transsphincteric fistulas (HTFs) are equivocal probably because most trials are small and comprise mixed patient populations. The aim of this study was to highlight the long-term efficacy of LIFT for HTFs in a large homogeneous sample and to determine the risk factors that contribute to non-healing resulting in failure and recurrence. METHOD: A retrospective study was performed which assessed patients with HTFs treated by LIFT without prior loose setons from September 2012 to December 2017. Continence function was evaluated by the Wexner incontinence scale and anal manometry. Quality of life was assessed by using the faecal incontinence quality of life (FIQL) scale with four domains: lifestyle, coping, depression and embarrassment. RESULTS: Seventy patients with HTFs underwent 71 LIFT procedures. The primary healing rate was 81.7% with a median follow-up duration of 16.5 (range 4.5-68) months. The healing rates of mature and immature fistulas were 83.7% and 77.3%, respectively. Two patients suffered failure with an unhealed intersphincteric wound. Recurrence occurred in 11 patients. Incontinence of flatus, present in four patients before surgery, improved postoperatively. Two patients undergoing LIFT combined with fistulotomy complained of flatus incontinence after surgery. No significant differences between preoperative and postoperative Wexner score, maximum resting pressure and maximum squeeze pressure were detected. The FIQL was improved in lifestyle, coping and depression. No risk factor for non-healing was found. CONCLUSION: LIFT has a promising long-term outcome for HTFs, with negligible impairment on continence and improved quality of life.


Assuntos
Canal Anal/cirurgia , Depressão/psicologia , Ligadura/métodos , Qualidade de Vida/psicologia , Fístula Retal/cirurgia , Adaptação Psicológica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Retal/psicologia , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
7.
Zhonghua Nei Ke Za Zhi ; 58(8): 599-601, 2019 Aug 01.
Artigo em Zh | MEDLINE | ID: mdl-31365983

RESUMO

Carotid web is a rare risk factor of ischemic stroke. A total of 32 (0.54%) patients with carotid web were finally diagnosed in 5 943 patients who underwent carotid computerized tomography angiography (CTA) in two hospitals. Only one patient received carotid endarterectomy that pathological findings were fibrous tissue hyperplasia of vascular wall with mucinous degeneration. Stent implantation was administrated in two cases. Among 13 asymptomatic patients, the observational follow-up period was (20.9±12.4) months without strokes. Carotid web is a rare aberration. Asymptomatic patients with carotid web are usually silent. Large sized cohort and long-term follow-up are further needed.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Stents/efeitos adversos , Artéria Carótida Interna/cirurgia , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/cirurgia , Estudos de Coortes , Endarterectomia das Carótidas/métodos , Displasia Fibromuscular/complicações , Seguimentos , Humanos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia
8.
Acta Anaesthesiol Scand ; 62(5): 687-700, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29363103

RESUMO

BACKGROUND: Regional anaesthesia may have advantages in preserving immune function. Tumor-infiltrating lymphocytes (TILs) are considered indicators of immune response in the tumor microenvironment and used as a prognostic marker in patients after cancer surgery. This study investigated the effects of combined epidural anaesthesia on the number of TILs in patients undergoing surgery for lung adenocarcinoma. METHODS: Patients undergoing radical resection for primary lung cancer were randomized to receive either combined epidural-general anaesthesia (Epi-GA) or general anaesthesia (GA) in an ongoing randomized controlled trial (ChiCTR-TRC-14004136). Excised adenocarcinoma specimens from patients enrolled between 1 June 2015 and 30 November 2015 were selected for immunohistochemical staining of CD8 and FOXP3 molecules. The numbers of positive lymphocytes were counted and expressed as the number of cells per mm2 tumor area. RESULTS: One hundred and twenty-eight patients were recruited and randomized; 64 patients were included in immunohistochemistry analysis (37 received Epi-GA vs. 27 received GA). The number of CD8+ T cells was higher in the Epi-GA group than in the GA group (median [interquartile range]: 292.8 [198.0-418.3] vs. 204.7 [131.1-305.8], P = 0.036); whereas the number of FOXP3+ T cells was less in the Epi-GA group than in the GA group (37.6 [14.7-92.3] vs. 99.8 [68.9-168.3], P < 0.001). CONCLUSIONS: For patients undergoing surgery for lung adenocarcinoma under general anesthesia, use of epidural anaesthesia increased CD8+ T cells infiltration but decreased FOXP3+ T cells accumulation in tumor tissues. Epidural anaesthesia may affect TILs in a manner that preserves immune function.


Assuntos
Adenocarcinoma de Pulmão/cirurgia , Anestesia Epidural , Neoplasias Pulmonares/cirurgia , Linfócitos do Interstício Tumoral/imunologia , Adenocarcinoma de Pulmão/imunologia , Idoso , Antígenos CD8/análise , Feminino , Fatores de Transcrição Forkhead/análise , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/imunologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Phys Rev Lett ; 119(16): 164801, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29099228

RESUMO

We present experimental studies on ion acceleration using an 800-nm circularly polarized laser pulse with a peak intensity of 6.9×10^{19} W/cm^{2} interacting with an overdense plasma that is produced by a laser prepulse ionizing an initially ultrathin plastic foil. The proton spectra exhibit spectral peaks at energies up to 9 MeV with energy spreads of 30% and fluxes as high as 3×10^{12} protons/MeV/sr. Two-dimensional particle-in-cell simulations reveal that collisionless shocks are efficiently launched by circularly polarized lasers in exploded plasmas, resulting in the acceleration of quasimonoenergetic proton beams. Furthermore, this scheme predicts the generation of quasimonoenergetic proton beams with peak energies of approximately 150 MeV using current laser technology, representing a significant step toward applications such as proton therapy.

10.
N Z Vet J ; 65(3): 119-123, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27817244

RESUMO

AIMS: To determine the difference in reproductive performance between cows detected in oestrus during morning or afternoon milking when artificial insemination (AI) was carried out once daily, either after the morning or afternoon milking. METHODS: The study used 20,816 records for cows in 30 spring calving dairy herds that used a camera-based system for oestrus detection during both morning and afternoon milkings. This system automatically determined whether a pressure-sensitive oestrus detection device had been activated or not, or was missing. In all study herds cows were milked twice daily and AI was performed by professional AI technicians once daily, after either morning or afternoon milking. The time of recorded oestrus was classified into AM or PM oestrus groups using 12:00 noon as the cut-off point and time of AI was classified into AM or PM AI groups using 13:00 as the cut-off point. Reproductive performance was determined using non-return to oestrus (NRR) between 2 and 24 days after AI, and was compared between oestrus and AI groups using generalised linear mixed models. RESULTS: Most AI (18,621/20,816; 89%) were carried out after morning milking, and more cows were recorded in oestrus during morning milking (12,328/20,816; 59%) than during afternoon milking (8,488/20,816; 41%). The NRR of cows inseminated after morning milking did not differ (OR=1.04; 95% CI=0.97-1.10) for cows recorded in oestrus in the morning (LSM=68.6 (95% CI=66.3-70.9)%) or afternoon (LSM=67.9 (95% CI=65.4-70.2)%); and did not differ for cows inseminated after the afternoon milking (OR=1.10; 95% CI=0.92-1.32) for cows recorded in oestrus in the morning (LSM=63.4 (95% CI=58.2-68.2)%) or afternoon (LSM=61.2 (95% CI=55.8-66.3)%). There were no differences in NRR between cows detected in oestrus during the morning or the afternoon milking after AI with either liquid (OR=1.04; 95% CI=0.97-1.12) or frozen-thawed (OR=1.02; 95% CI=0.88-1.18) semen. CONCLUSIONS AND CLINICAL RELEVANCE: Results from the present study show that, under New Zealand conditions, the difference in NRR between cows first detected in oestrus during morning milking and those first detected in oestrus during afternoon milking is likely small when AI is carried out once daily after either morning or afternoon milking, regardless of whether the semen used for AI is liquid or frozen. Because twice daily AI is more costly than once daily AI, these results do not support a change to the current once daily AI practice in New Zealand.


Assuntos
Bovinos/fisiologia , Estro/fisiologia , Inseminação Artificial/veterinária , Lactação , Criação de Animais Domésticos , Animais , Feminino , Gravidez , Fatores de Tempo
11.
Phys Rev Lett ; 117(12): 124801, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27689280

RESUMO

By designing a structured gas density profile between the dual-stage gas jets to manipulate electron seeding and energy chirp reversal for compressing the energy spread, we have experimentally produced high-brightness high-energy electron beams from a cascaded laser wakefield accelerator with peak energies in the range of 200-600 MeV, 0.4%-1.2% rms energy spread, 10-80 pC charge, and ∼0.2 mrad rms divergence. The maximum six-dimensional brightness B_{6D,n} is estimated as ∼6.5×10^{15} A/m^{2}/0.1%, which is very close to the typical brightness of e beams from state-of-the-art linac drivers. These high-brightness high-energy e beams may lead to the realization of compact monoenergetic gamma-ray and intense coherent x-ray radiation sources.

12.
Zhonghua Yan Ke Za Zhi ; 52(9): 657-62, 2016 Sep 11.
Artigo em Zh | MEDLINE | ID: mdl-27647245

RESUMO

OBJECTIVE: To evaluate the efficacy of topical voriconazole in patients with fungal keratitis caused by different fungal species. METHODS: Interventional case series. Eighty-four patients aged 18 years or older from central China with confirmed fungal keratitis who presented at the outpatient department of Henan Eye Institute were enrolled in the study. The patients underwent in vivo confocal scanning laser microscopy examination, coneal scraping and microscopic examination and fungal culture, and then received topical voriconazole, closed curative effects were conducted. The sensitivity of three different diagnostic techniques, spectrum of the fungi, cure rate for fungal corneal infection related to each species were analyzed. RESULTS: In our study, 84 patients were diagnosed with fungal keratitis based on clinical symptoms, and results of at least one of the examinations of in vivo confocal scanning laser microscopy, conventional smear, and corneal scraping culture and the sensitivity were 92.85%(78/84), 85.71%(72/84), 84.52%(71/84)respectively. In viro confocal scanning laser microscopy. Successful management was achieved in 83.33% of the patients. Topical voriconazole treatment failed in 14 patients(16.67%), who required surgical treatment. In 36 patients with Fusarium corneal infections, 26(72.22%)were successfully treated with topical voriconazole; however, in 18 patients with Aspergillus corneal infections and 7 patients with Alternaria corneal infections, 94.44% and 100.00% of them were successfully treated, respectively. In a case-based dynamic tracking study, in vivo confocal microscopy provided real-time dynamic detection of surviving hyphae. The existence of hyphae was(38.35±17.32)days for Fusarium,(25.00±16.11)days for Aspergillus,(21.00±4.36)days for Alternaria, and(41.50±31.68)days for the focus in the deep stroma. The duration of treatment was similar for all four groups. CONCLUSIONS: Topical application of voriconazole is on effective method for the freatment of fungal keratitis Topical voriconazole is highly effective for fungal keratitis caused by Alternaria spp. and Aspergillus, however, for Fusarium, it is relatively low effective. (Chin J Ophthalmol, 2016, 52: 657-662).


Assuntos
Antifúngicos/administração & dosagem , Infecções Oculares Fúngicas/tratamento farmacológico , Ceratite/tratamento farmacológico , Voriconazol/administração & dosagem , Administração Tópica , Adulto , Alternariose/tratamento farmacológico , Aspergilose/tratamento farmacológico , China , Infecções Oculares Fúngicas/microbiologia , Feminino , Fusariose/tratamento farmacológico , Humanos , Ceratite/microbiologia , Masculino , Resultado do Tratamento
13.
Clin Exp Obstet Gynecol ; 42(1): 62-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25864284

RESUMO

OBJECTIVE: This study aims to investigate the number changes and the clinical significance of the peripheral blood T lymphocyte subsets and NK (natural killer) cells in unexplained recurrent spontaneous abortion (URSA) patients before and after abortion, as well as after successful pregnancy. MATERIALS AND METHODS: Thirty-nine URSA patients (URSA-abortion group), among who 22 patients were followed up until the final successful parturition (URSA-pregnancy group), 31 normal-pregnancy (NP) cases and 25 normal non-pregnancy (NNP) control cases in which the peripheral blood T lymphocytes and subsets, B cells, and NK cells were assessed flow cytometry. RESULTS: Compared with the URSA-pregnancy group and the NP group, the Th cells and NK cells of the URSA-abortion group increased (p < 0.05); compared with the NNP group, the total number of T cells decreased after the first, second, and third month of the URSA abortion (p < 0.05); Th cells decreased within one to six months of the URSA abortion (p < 0.05); proportion of NK cells was significantly higher in URSA patients (p < 0.05). CONCLUSION: The abnormal numbers of the peripheral blood T cell subsets and NK cells were related with the occurrence of URSA.


Assuntos
Aborto Habitual/sangue , Células Matadoras Naturais , Subpopulações de Linfócitos T , Linfócitos T Auxiliares-Indutores , Linfócitos T Reguladores , Adulto , Contagem de Células Sanguíneas/métodos , Feminino , Citometria de Fluxo/métodos , Humanos , Gravidez
14.
J Dairy Sci ; 97(11): 7298-304, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25218757

RESUMO

The objective was to compare reproductive performance of liquid sex-sorted (SS) semen with that of conventional (CON) semen in lactating dairy cows. Between 2011 and 2013, commercial dairy herds (n = 101, 203, and 253 for 2011, 2012, and 2013, respectively) with predominantly Holstein-Friesian cows were enrolled in a contract mating program to produce surplus heifers for export using liquid SS semen. During the spring mating period, each herd was allocated with liquid SS semen at 50% of its daily requirement and the remaining daily requirement was allocated with CON liquid semen. Sperm for producing SS semen was sorted by Sexing Technologies NZ Ltd. (Hamilton, New Zealand) and then packaged using the liquid semen technology of LIC (Hamilton, New Zealand) at a dose of 1 × 10(6) sperm. Artificial insemination (AI) with liquid SS semen was carried out between 43 and 46 h after collection. Conventional semen straws contained 1.25 × 10(6), 1.75 × 10(6), or 2 × 10(6) sperm for semen to be used on d 1, 2, or 3 after collection, respectively. Only CON inseminations on the same days as when SS semen was used were included in the comparison. Herd managers biased usage of SS semen toward cows with a longer postpartum interval before the mating start date (64.0 vs. 62.8 d), cows of higher genetic merit (NZ$107.0 vs. NZ$98.4), younger cows (5.1 vs. 5.2 yr), and cows in which they had more confidence of being genuinely in estrus as measured by a lower percentage of short returns between 1 and 17 d (5.3 vs. 7.5%). After adjusting for these factors, the estimated difference in nonreturn rate between AI with SS and CON semen over the 3 seasons was -3.8 percentage points (SS = 70.2% vs. CON = 74.0%; SS/CON = 94.9%). The estimated maximum difference in calving rate per AI between SS and CON semen was -3.1 percentage points for 2011 (SS = 51.2% vs. CON = 54.3%; SS/CON = 94.3%) and -3.0 percentage points for 2012 (SS = 49.7% vs. CON = 52.6%; SS/CON = 94.5%). Calving data for 2013 were not yet available. The percentage of heifer calves born to AI with SS semen was 87.0% for 2011 and 85.8% for 2012, both of which were lower than the expectation of 90% mainly due to misidentification of calf dams in seasonal dairy herds calving on pasture. In summary, results in this report showed that liquid SS semen only required half the dose rate of frozen SS semen to achieve a reproductive performance of over 94% of CON semen in lactating dairy cows. Careful planning and a robust distribution network are required to avoid semen wastage and to maximize the benefit of liquid SS semen.


Assuntos
Bovinos/fisiologia , Fertilização/fisiologia , Inseminação Artificial/veterinária , Sêmen/fisiologia , Pré-Seleção do Sexo/veterinária , Animais , Indústria de Laticínios , Feminino , Masculino , Nova Zelândia , Gravidez
15.
Phys Rev Lett ; 110(1): 013001, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23383786

RESUMO

A calculation of the second-order (rescattering) term in the S-matrix expansion of above-threshold ionization is presented for the case when the binding potential is the unscreened Coulomb potential. Technical problems related to the divergence of the Coulomb scattering amplitude are avoided in the theory by considering the depletion of the atomic ground state due to the applied laser field, which is well defined and does not require the introduction of a screening constant. We focus on the low-energy structure, which was observed in recent experiments with a midinfrared wavelength laser field. Both the spectra and, in particular, the observed scaling versus the Keldysh parameter and the ponderomotive energy are reproduced. The theory provides evidence that the origin of the structure lies in the long-range Coulomb interaction.

16.
Opt Express ; 20(3): 2924-31, 2012 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-22330530

RESUMO

By deviating the nanodisk from the center in the silver nanocrescent/nanodisk structure, we find that the dipole, quadrupole and octupole modes can all induce very high local electric field enhancement (LFE, more than 750) for the coupling of nanocrescent and crescent gap modes, which makes the resonant wavelengths of the non-concentric nanostructures change from the visible to near infrared regions. In addition, the LFE factor of the quadrupole mode is more than 1000, which is suitable for single molecular detection by local surface enhanced spectroscopy.


Assuntos
Raios Infravermelhos , Modelos Teóricos , Simulação por Computador , Luz , Espalhamento de Radiação , Ressonância de Plasmônio de Superfície
17.
Opt Lett ; 37(23): 4919-21, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23202090

RESUMO

This Letter presents a plasmonic nanostructure consisting of a nanodisk and a nanoring. The nanodisk is outside of the nanoring. The quadrupolar, hexapolar, and octupolar resonance modes of the nanoring are excited easily by the bright dipolar mode of nanodisks. This nanostructure shows strong interaction and deep Fano dips. In addition, the resonance frequency, depth, and line width of Fano dips can be tuned by changing the geometrical parameters of the nanodisk and nanoring. These plasmonic nanostructures show both high contrast ratio and high figure of merit. Such characters make them suitable for chemical and biological sensing.

18.
Opt Lett ; 37(23): 4829-31, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23202060

RESUMO

We propose a technique for measuring infrared femtosecond pulses: transient-grating self-referenced spectral interferometry. Based on this technique, we built an extremely simple, alignment-free device and successfully characterized both 38 fs pulses at 800 nm and sub-two-cycle 10 fs pulses at 1.75 µm.


Assuntos
Interferometria/métodos , Fenômenos Ópticos , Espectrofotometria Infravermelho/métodos , Interferometria/instrumentação , Espectrofotometria Infravermelho/instrumentação , Fatores de Tempo
19.
Br J Anaesth ; 108(4): 662-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22307241

RESUMO

BACKGROUND: There is increasing interest in RNA interference in pain research using the intrathecal route to deliver small-interfering RNA (siRNA). An interferon (IFN) response is a common side-effect of siRNA. However, the IFN response in the spinal cord after intrathecal administration of siRNA remains unknown. We hypothesized that high doses of siRNAs can elicit off-target analgesia via releasing IFN-α. We investigated the IFN response and its role in regulating pain sensitivity in the spinal cords after intrathecal administration of siRNAs. METHODS: Male Sprague-Dawley rats were given intrathecal injections of non-targeting (NT) siRNAs or IFN-α and tested for complete Freund's adjuvant (CFA)-induced mechanical allodynia and heat hyperalgesia. IFN-α in the spinal cord after injection of NT siRNAs was measured by western blotting and immunohistochemical staining. RESULTS: IFN-α was up-regulated in the spinal cord after intrathecal treatment of NT siRNAs. Intrathecal injection of NT siRNAs, at high doses of 10 or 20 µg, reduced CFA-induced inflammatory pain (P<0.05). Intrathecal application of IFN-α inhibited pain hypersensitivity in inflamed rats and produced analgesia in naïve rats (P<0.05). Notably, the anti-nociceptive effects elicited by NT siRNAs and IFN-α were reversed by IFN-α neutralizing antibody and naloxone. CONCLUSIONS: Our data suggest that (i) intrathecal administration of high doses of siRNA (≥ 10 µg) induced up-regulation of IFN-α in the spinal cord and produced analgesic effects through IFN-α, and (ii) IFN-α's analgesic effect is mediated via opioid receptors. Caution must be taken to avoid IFN-α-mediated analgesic effects of siRNAs in pain research.


Assuntos
Analgesia/métodos , Interferon-alfa/farmacologia , Dor/tratamento farmacológico , RNA Interferente Pequeno/farmacologia , Animais , Western Blotting , Modelos Animais de Doenças , Adjuvante de Freund/administração & dosagem , Adjuvante de Freund/farmacologia , Hiperalgesia/tratamento farmacológico , Fatores Imunológicos/farmacologia , Inflamação/complicações , Inflamação/tratamento farmacológico , Injeções Espinhais , Interferon-alfa/administração & dosagem , Masculino , Dor/complicações , Manejo da Dor/métodos , Limiar da Dor/efeitos dos fármacos , RNA Interferente Pequeno/administração & dosagem , Ratos , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
20.
Phys Rev Lett ; 107(3): 035001, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21838367

RESUMO

We report on near-GeV electron beam generation from an all-optical cascaded laser wakefield accelerator (LWFA). Electron injection and acceleration are successfully separated and controlled in different LWFA stages by employing two gas cells filled with a He/O2 mixture and pure He gas, respectively. Electrons with a Maxwellian spectrum, generated from the first LWFA assisted by ionization-induced injection, were seeded into the second LWFA with a 3-mm-thick gas cell and accelerated to be a 0.8-GeV quasimonoenergetic electron beam, corresponding to an acceleration gradient of 187 GV/m. The demonstrated scheme paves the way towards the multi-GeV laser accelerators.

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