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1.
Hum Reprod ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38850031

RESUMO

STUDY QUESTION: Do women with endometriosis who achieve a live birth (LB) after HRT-frozen embryo transfer (HRT-FET) have different progesterone levels on the day of transfer compared to unaffected women? SUMMARY ANSWER: In women achieving a LB after HRT-FET, serum progesterone levels on the day of the transfer did not differ between patients with endometriosis and unaffected patients. WHAT IS KNOWN ALREADY: In HRT-FET, several studies have highlighted the correlation between serum progesterone levels at the time of FET and LB rates. In the pathophysiology of endometriosis, progesterone resistance is typically described in the eutopic endometrium. This has led to the hypothesis that women with endometriosis may require higher progesterone levels to achieve a LB, especially in HRT-FET cycles without a corpus luteum. STUDY DESIGN, SIZE, DURATION: We conducted an observational cohort study at the university-based reproductive medicine center of our institution, focusing on women who underwent a single autologous frozen blastocyst transfer after HRT using exogenous estradiol and micronized vaginal progesterone for endometrial preparation between January 2019 and December 2021. Women were included only once during the study period. Serum progesterone levels were measured on the morning of the FET by a single laboratory. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients were divided into groups based on whether they had endometriosis or not and whether they achieved a LB. The diagnosis of endometriosis was based on published imaging criteria (transvaginal sonography/magnetic resonance imaging) and/or confirmed histology. The primary outcome was progesterone levels on the day of the HRT-FET leading to a LB in patients with endometriosis compared to unaffected women. Subgroup analyses were performed based on the presence of deep infiltrating endometriosis or adenomyosis. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 1784 patients were included. The mean age of the women was 35.1 ± 4.1 (SD) years. Five hundred and sixty women had endometriosis, while 1224 did not. About 179/560 (32.0%) with endometriosis and 381/1224 (31.2%) without endometriosis achieved a LB. Among women who achieved a LB after HRT-FET, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (13.6 ± 4.3 ng/ml vs 13.2 ± 4.4 ng/ml, respectively; P = 0.302). In the subgroup of women with deep infiltrating endometriosis (n = 142) and adenomyosis (n = 100), the mean progesterone level was 13.1 ± 4.1 ng/ml and 12.6 ± 3.7 ng/ml, respectively, with no significant difference compared to endometriosis-free patients. After adjusting for BMI, parity, duration of infertility, tobacco use, and geographic origin, neither the presence of endometriosis (coefficient 0.38; 95% CI: -0.63 to 1.40; P = 0.457) nor the presence of adenomyosis (coefficient 0.97; 95% CI: -0.24 to 2.19; P = 0.114) was associated with the progesterone level on the day of HRT-FET. Among women who did not conceive, there was no significant difference in the mean progesterone level on the day of the HRT-FET between those with endometriosis and those without (P = 0.709). LIMITATIONS, REASONS FOR CAUTION: The primary limitation of our study is associated with its observational design. Extrapolating our results to other laboratories or different routes and/or dosages of administering progesterone also requires validation. WIDER IMPLICATIONS OF THE FINDINGS: This study shows that patients diagnosed with endometriosis do not require higher progesterone levels on the day of a frozen blastocyst transfer to achieve a LB in hormonal replacement therapy cycles. STUDY FUNDING/COMPETING INTEREST(S): None declared. TRIAL REGISTRATION NUMBER: N/A.

2.
Opt Express ; 31(18): 29166-29173, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710722

RESUMO

Cylindrical vector (CV) beams have sparked considerable interest due to their extraordinary vectorial properties, desirable for applications ranging from microscopy to high energy physics. Increasing demand for cost-effective, small-footprint photonics has fueled the development of photonic integrated circuits (PICs) capable of generating structured light beams in recent years. This technology however suffers from low reconfigurability, limiting the variety of CV beams that can be generated from these devices. In this article, we propose a novel design to overcome this limitation, which exploits the polarization-dependent response of annular gratings embedded into a microring resonator to generate re-configurable CV beams. We demonstrate the viability of the device in a proof-of-principle experiment including spatially resolved Stokes measurements.

3.
Opt Lett ; 45(13): 3529-3532, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32630890

RESUMO

A distributed feedback GaAs-based semiconductor laser with a laterally coupled grating is demonstrated at a wavelength of 780.24 nm with up to 60 mW power. A mode expander and aluminum-free active layers have been used to reduce the linewidth to 612 kHz while maintaining high output power. The laser demonstrates over 40 dB side-mode suppression ratio with >0.3nm of tuning suitable for atom cooling experiments with the D2 87Rb atomic transition. This laser has substantial potential to be integrated into miniaturized cold atom systems.

4.
Opt Express ; 27(5): 7365-7372, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30876301

RESUMO

In this paper, we report the generation of an ultra-sharp asymmetric resonance spectrum through Fano-like interference. This generation is accomplished by weakly coupling a high-quality factor (Q factor) Fabry-Pérot (FP) cavity and a low-Q factor FP cavity through evanescent waves. The high-Q FP cavity is formed by Sagnac loop mirrors, whilst the low-Q one is built by partially transmitting Sagnac loop reflectors. The working principle has been analytically established and numerically modelled by using temporal coupled-mode-theory (CMT), and verified using a prototype device fabricated on the 340 nm silicon-on-insulator (SOI) platform, patterned by deep ultraviolet (DUV) lithography. Pronounced asymmetric resonances with slopes up to 0.77 dB/pm have been successfully measured, which, to the best of our knowledge, is higher than the results reported in state-of-the-art devices in on-chip integrated Si photonic studies. The established theoretical analysis method can provide excellent design guidelines for devices with Fano-like resonances. The design principle can be applied to ultra-sensitive sensing, ultra-high extinction ratio switching, and more applications.

5.
Opt Express ; 26(20): 25667-25675, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30469665

RESUMO

Germanium-on-silicon waveguides were modeled, fabricated and characterized at wavelengths ranging from 7.5 to 11 µm. Measured waveguide losses are below 5 dB/cm for both TE and TM polarization and reach values of ∼ 1 dB/cm for ≥ 10 µm wavelengths for the TE polarization. This work demonstrates experimentally for the first time that Ge-on-Si is a viable waveguide platform for sensing in the molecular fingerprint spectral region. Detailed modeling and analysis is presented to identify the various loss contributions, showing that with practical techniques losses below 1 dB/cm could be achieved across the full measurement range.

6.
Opt Lett ; 43(20): 4883-4886, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30320774

RESUMO

Hybrid integration of a III-V microdisk resonator on a silicon-on-insulator waveguide platform is demonstrated. Transfer printing with nanoscale accuracy is used to micro-assemble an evanescently coupled all-pass microdisk resonator with a targeted coupler gap of 100 nm using pre-fabricated AlGaAs and silicon components. Transmission measurements show hybrid resonances with a loaded Q-factor of 7×103 and a cavity finesse of over 100.

7.
Eur J Pain ; 20(9): 1413-22, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27061948

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) can relieve neuropathic pain when applied at high frequency (HF: 5-20 Hz) over the primary motor cortex (M1), contralateral to pain side. In most studies, rTMS is delivered over the hand motor hot spot (hMHS), whatever pain location. Navigation systems have been developed to guide rTMS targeting, but their value to improve rTMS efficacy remains to be demonstrated. OBJECTIVE: To compare the analgesic efficacy of HF-rTMS targeting the hMHS (non-navigated procedure) or the M1 representation of the pain region (navigated procedure). METHODS: The analgesic effect of a single session of 10 Hz-rTMS of M1 was assessed in 66 patients with neuropathic pain of various causes and locations, according to three conditions: sham or active non-navigated rTMS of the hMHS and active navigated rTMS of the pain region. RESULTS: Pain was relieved by both active rTMS conditions, and not by sham. Pain location influenced the results: upper or lower limb pain was significantly relieved, but not facial or hemibody pain. Pain relief lasted 1 week only after navigated rTMS, compared to sham. CONCLUSION: Navigation may improve HF-rTMS efficacy in patients with limb pain, whereas targeting remains to be optimized for more diffuse or facial pain. WHAT DOES THIS STUDY ADD?: To produce analgesic effects, HF-rTMS should be applied over the precentral cortex contralaterally to the painful side. Although the hMHS is the target normally chosen for stimulation, the optimal target has not been defined yet. Neuronavigational methods have been recently developed; they allow the integration of MRI data and are thought to improve rTMS efficacy.


Assuntos
Dor Crônica/terapia , Córtex Motor/fisiopatologia , Neuralgia/terapia , Manejo da Dor/métodos , Estimulação Magnética Transcraniana/métodos , Adolescente , Adulto , Idoso , Dor Crônica/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuralgia/fisiopatologia , Medição da Dor/métodos , Resultado do Tratamento , Adulto Jovem
8.
Nat Commun ; 6: 7948, 2015 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-26245267

RESUMO

Entanglement--one of the most delicate phenomena in nature--is an essential resource for quantum information applications. Scalable photonic quantum devices must generate and control qubit entanglement on-chip, where quantum information is naturally encoded in photon path. Here we report a silicon photonic chip that uses resonant-enhanced photon-pair sources, spectral demultiplexers and reconfigurable optics to generate a path-entangled two-qubit state and analyse its entanglement. We show that ring-resonator-based spontaneous four-wave mixing photon-pair sources can be made highly indistinguishable and that their spectral correlations are small. We use on-chip frequency demultiplexers and reconfigurable optics to perform both quantum state tomography and the strict Bell-CHSH test, both of which confirm a high level of on-chip entanglement. This work demonstrates the integration of high-performance components that will be essential for building quantum devices and systems to harness photonic entanglement on the large scale.

9.
Mol Plant Microbe Interact ; 27(9): 1014-24, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25105805

RESUMO

We previously showed that allelic genes mol¹ and mo1² used to protect lettuce crops against Lettuce mosaic virus (LMV) correspond to mutant alleles of the gene encoding the eukaryotic translation initiation factor 4E. LMV resistance-breaking determinants map not only to the main potyvirus virulence determinant, a genome-linked viral protein, but also to the C-terminal region of the cylindrical inclusion (CI), with a key role of amino acid at position 621. Here, we show that the propagation of several non-lettuce isolates of LMV in mo1¹ plants is accompanied by a gain of virulence correlated with the presence in the CI C terminus of a serine at position 617 and the accumulation of mutations at positions 602 or 627. Whole-genome sequencing of native and evolved isolates showed that no other mutation could be associated with adaptation to mo1 resistance. Site-directed mutagenesis pinpointed the key role in the virulence of the combination of mutations at positions 602 and 617, in addition to position 621. The impact of these mutations on the fitness of the virus was evaluated, suggesting that the durability of mo1 resistance in the field relies on the fitness cost associated with the resistance-breaking mutations, the nature of the mutations, and their potential antagonistic effects.


Assuntos
Adaptação Fisiológica , Fator de Iniciação 4E em Eucariotos/metabolismo , Lactuca/virologia , Doenças das Plantas/virologia , Potyvirus/genética , Proteínas Virais/genética , Alelos , Sequência de Aminoácidos , Resistência à Doença , Fator de Iniciação 4E em Eucariotos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Lactuca/imunologia , Mutagênese Sítio-Dirigida , Mutação , Doenças das Plantas/imunologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Potyvirus/patogenicidade , Potyvirus/fisiologia , Análise de Sequência de DNA , Especificidade da Espécie , Proteínas Virais/metabolismo , Virulência
10.
Opt Express ; 22(5): 5291-8, 2014 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663870

RESUMO

Aluminum Gallium Arsenide (AlGaAs) is an attractive platform for the development of integrated optical circuits for all-optical signal processing thanks to its large nonlinear coefficients in the 1.55-µm telecommunication spectral region. In this paper we discuss the results of the nonlinear continuous-wave optical characterization of AlGaAs waveguides at a wavelength of 1.55 µm. We also report the highest value ever reported in the literature for the real part of the nonlinear coefficient in this material (Re(γ) ≈521 W(-1)m(-1)).

11.
Mol Plant Microbe Interact ; 27(3): 215-26, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24405034

RESUMO

A unique feature shared by all plant viruses of the Potyviridae family is the induction of characteristic pinwheel-shaped inclusion bodies in the cytoplasm of infected cells. These cylindrical inclusions are composed of the viral-encoded cylindrical inclusion helicase (CI protein). Its helicase activity was characterized and its involvement in replication demonstrated through different reverse genetics approaches. In addition to replication, the CI protein is also involved in cell-to-cell and long-distance movements, possibly through interactions with the recently discovered viral P3N-PIPO protein. Studies over the past two decades demonstrate that the CI protein is present in several cellular compartments interacting with viral and plant protein partners likely involved in its various roles in different steps of viral infection. Furthermore, the CI protein acts as an avirulence factor in gene-for-gene interactions with dominant-resistance host genes and as a recessive-resistance overcoming factor. Although a significant amount of data concerning the potential functions and subcellular localization of this protein has been published, no synthetic review is available on this important multifunctional protein. In this review, we compile and integrate all information relevant to the current understanding of this viral protein structure and function and present a mode of action for CI, combining replication and movement.


Assuntos
Genoma Viral/fisiologia , Corpos de Inclusão Viral/metabolismo , Doenças das Plantas/virologia , Plantas/virologia , Potyviridae/enzimologia , RNA Helicases/metabolismo , Sequência de Aminoácidos , Interações Hospedeiro-Patógeno , Corpos de Inclusão Viral/química , Corpos de Inclusão Viral/ultraestrutura , Modelos Biológicos , Dados de Sequência Molecular , Vírus de Plantas/enzimologia , Vírus de Plantas/fisiologia , Vírus de Plantas/ultraestrutura , Plantas/ultraestrutura , Plasmodesmos/ultraestrutura , Plasmodesmos/virologia , Potyviridae/fisiologia , Potyviridae/ultraestrutura , RNA Helicases/química , RNA Helicases/ultraestrutura , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/metabolismo , Proteínas Virais/ultraestrutura
12.
Opt Express ; 21(18): 21587-95, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24104033

RESUMO

We report on the experimental demonstration of a novel silicon based fully integrated nonlinear Mach Zehnder device. A standard silicon waveguide is used as a nonlinear arm, conversely a large mode SU-8 waveguide acts as a purely linear arm. Given this asymmetry, an intensity dependent phase shift can be introduced between the two interferometric arms. Thanks to a fine tuning of the silicon arm optical properties, a low power, ultrafast, picosecond operation is demonstrated, allowing the use of this device for ultrafast all-optical signal processing in high density communication networks.

13.
Eur J Pain ; 16(10): 1403-13, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22508405

RESUMO

BACKGROUND: 'Conventional' protocols of high-frequency repetitive transcranial magnetic stimulation (rTMS) delivered to M1 can produce analgesia. Theta burst stimulation (TBS), a novel rTMS paradigm, is thought to produce greater changes in M1 excitability than 'conventional' protocols. After a preliminary experiment showing no analgesic effect of continuous or intermittent TBS trains (cTBS or iTBS) delivered to M1 as single procedures, we used TBS to prime a subsequent session of 'conventional' 10 Hz-rTMS. METHODS: In 14 patients with chronic refractory neuropathic pain, navigated rTMS was targeted over M1 hand region, contralateral to painful side. Analgesic effects were daily assessed on a visual analogue scale for the week after each 10 Hz-rTMS session, preceded or not by TBS priming. In an additional experiment, the effects on cortical excitability parameters provided by single- and paired-pulse TMS paradigms were studied. RESULTS: Pain level was reduced after any type of rTMS procedure compared to baseline, but iTBS priming produced greater analgesia than the other protocols. Regarding motor cortex excitability changes, the analgesic effects were associated with an increase in intracortical inhibition, whatever the type of stimulation, primed or non-primed. CONCLUSIONS: The present results show that the analgesic effects of 'conventional' 10 Hz-rTMS delivered to M1 can be enhanced by TBS priming, at least using iTBS. Interestingly, the application of cTBS and iTBS did not produce opposite modulations, unlike previously reported in other systems. It remains to be determined whether the interest of TBS priming is to generate a simple additive effect or a more specific process of cortical plasticity.


Assuntos
Córtex Motor/fisiologia , Neuralgia/terapia , Dor Intratável/terapia , Estimulação Magnética Transcraniana/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inibição Neural , Medição da Dor , Resultado do Tratamento
14.
Opt Lett ; 37(4): 668-70, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22344142

RESUMO

We report frequency conversion experiments in silicon-on-insulator (SOI) directional couplers. We demonstrate that the evanescent coupling between two subwavelength SOI waveguides is strongly dispersive and significantly modifies modulational instability (MI) spectra through the coupling induced group velocity dispersion (GVD). As the separation between two 380-nm-wide silicon photonic wires decreases, the increasing dispersion of the coupling makes the GVD in the symmetric supermode more normal and suppresses the bandwidth of the MI gain observed for larger separations.

15.
Opt Express ; 19(20): 19514-22, 2011 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-21996892

RESUMO

We report the first realization of integrated, all-optical first- and higher-order photonic differentiators operating at terahertz (THz) processing speeds. This is accomplished in a Silicon-on-Insulator (SOI) CMOS-compatible platform using a simple integrated geometry based on (π-)phase-shifted Bragg gratings. Moreover, we achieve on-chip generation of sub-picosecond Hermite-Gaussian pulse waveforms, which are noteworthy for applications in next-generation optical telecommunications.


Assuntos
Simulação por Computador , Luz , Modelos Teóricos , Óptica e Fotônica/instrumentação , Refratometria/instrumentação , Espalhamento de Radiação , Telecomunicações/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento
16.
Opt Lett ; 36(19): 3717-9, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21964074

RESUMO

We demonstrate a method for the efficient modulation of optical wavelengths around 1550 nm in silicon waveguides. The amplitude of a propagating signal is mediated via control of the charge state of indium centers, rather than using free-carriers alone as in the plasma-dispersion effect. A 1×1 switch formed of an integrated p-i-n junction in an indium-doped silicon on insulator (SOI) waveguide provides 'normally-off' silicon absorption of greater than 7 dB at zero bias. This loss is decreased to 2.8 dB with application of a 6 V applied reverse bias, with a power consumption of less than 1 µW.

17.
Opt Express ; 19(13): 12408-17, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21716479

RESUMO

We report modal phase matched (MPM) second harmonic generation (SHG) in high-index contrast AlGaAs sub-micron ridge waveguides, by way of sub-mW continuous wave powers at telecommunication wavelengths. We achieve an experimental normalized conversion efficiency of ~14%/W/cm2, obtained through a careful sub-wavelength design supporting both the phase matching requirement and a significant overlap efficiency. Furthermore, the weak anomalous dispersion, robust fabrication technology and possible geometrical and thermal tuning of the device functionality enable a fully integrated multi-functional chip for several critical areas in telecommunications, including wavelength (time) division multiplexing and quantum entanglement.


Assuntos
Compostos de Alumínio/química , Arsenicais/química , Gálio/química , Dispositivos Ópticos , Óptica e Fotônica/instrumentação , Lasers de Corante , Luz , Manufaturas , Modelos Teóricos , Óptica e Fotônica/métodos , Semicondutores
18.
Opt Express ; 18(25): 26625-30, 2010 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21165011

RESUMO

We report time domain measurements of the group-velocity-dispersion-induced and nonlinearity-induced chirping of femtosecond pulses in subwavelength silicon-on-insulator waveguides. We observe that at a critical input power level, these two effects compensate each other leading to soliton formation. Formation of the fundamental optical soliton is observed at a peak power of a few Watts inside the waveguide. Interferometric cross-correlation traces reveal compression of the soliton pulses, while spectral measurements show pronounced dispersive waves emitted by solitons into the wavelength range of normal group velocity dispersion.


Assuntos
Interpretação Estatística de Dados , Modelos Estatísticos , Refratometria/instrumentação , Silício/química , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação , Estatística como Assunto
19.
Phys Rev Lett ; 105(18): 181801, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-21231096

RESUMO

The MiniBooNE experiment at Fermilab reports results from a search for ¯ν_{µ}→¯ν_{e} oscillations, using a data sample corresponding to 5.66×10²° protons on target. An excess of 20.9±14.0 events is observed in the energy range 475

20.
Phys Rev Lett ; 103(11): 111801, 2009 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-19792365

RESUMO

The MiniBooNE Collaboration reports initial results from a search for nu(mu)-->nu(e) oscillations. A signal-blind analysis was performed using a data sample corresponding to 3.39x10(20) protons on target. The data are consistent with background prediction across the full range of neutrino energy reconstructed assuming quasielastic scattering, 200

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