Harmonic generation from silicon membranes at visible and ultraviolet wavelengths.

Nonlinear silicon photonics offers unique abilities to generate, manipulate and detect optical signals in nano-devices, with applications based on field localization and large third order nonlinearity. However, at the nanoscale, inefficient nonlinear processes, absorption, and the lack of realistic models limit the nano-engineering of silicon. Here we report measurements of second and third harmonic generation from undoped silicon membranes. Using experimental results and simulations we identify the effective mass of valence electrons, which determines second harmonic generation efficiency, and oscillator parameters that control third order processes. We can then accurately predict the nonlinear optical properties of complex structures, without introducing and artificially separating the effective χ(2) into surface and volume contributions, and by simultaneously including effects of linear and nonlinear dispersions. Our results suggest that judicious exploitation of the nonlinear dispersion of ordinary semiconductors can provide reasonable nonlinear efficiencies and transformational device physics well into the UV range.

Carcinoma intraductal de próstata concomitante y respuesta al tratamiento hormonal en el carcinoma de próstata metastásico / Concomitant intraductal carcinoma of the prostate and response to hormonal therapy in metastatic prostate carcinoma

Introducción y objetivo: La mayoría de los cánceres de próstata (CP) se clasifican como adenocarcinoma acinar. El carcinoma intraductal de la próstata (CIDP) es una entidad histológica distinta que se cree que representa la propagación retrógrada del adenocarcinoma acinar invasivo en los conductos prostáticos y acinos.Hemos analizado el impacto del CIDP en pacientes con cáncer de próstata resistente a la castración metastásico (CPRCm) y sin tratamiento hormonal previo (hormone-naïve).Pacientes y métodosEvaluamos retrospectivamente a 118 pacientes con CPRCm con diagnóstico inicial de cáncer de prostata metastásico (CPM) desde mayo del 2010 hasta septiembre del 2018. El grupo uno incluyó 81 personas con CPM con adenocarcinoma acinar y el grupo dos estuvo compuesto por 37 pacientes con CPM con CIDP.ResultadosLa edad media de presentación fue de 76 años (IQR 73,4 a 78,7) en el grupo uno y de 74 años (68,5 a 80,6) en el grupo dos. El valor medio del PSA en el momento del diagnóstico fue de 619 ng/mL (IQR 85 a 1.113) y 868 ng/mL (IQR 186 a 1.922), respectivamente. El tiempo hasta la resistencia a la castración fue de 24,7 meses (IQR 16,7 a 32,7) en el grupo uno y 10,2 meses (IQR 4,2 a 16,2) en el grupo dos (p = 0,007). El tiempo hasta la progresión en los pacientes con cáncer de próstata resistente a la castración (CPRC) fue: 10,6 meses (IQR 5,6 a 15,6) y 6,2 meses (3,2 a 9,2), respectivamente (p = 0,05). La supervivencia global fue de 57,9 meses en el grupo uno (IC 95% 56,4 a 59,5) y de 38 meses (IC 95% 19,9 a 48,06) en el grupo dos (p = 0,001). En el análisis multivariante, el subtipo de adenocarcinoma fue estadísticamente significativo p 0,014, IC 95% (Hazard Ratio [HR] 0,058, 0,006 a 0,56).ConclusionesEl CIDP parece ser un subtipo de CP que se asocia con una respuesta más corta al tratamiento hormonal cuando se compara con el adenocarcinoma acinar en pacientes con cáncer metastásico. (AU)

Introduction and objective: Most prostate cancers are classified as acinar adenocarcinoma. Intraductal carcinoma of the prostate (IDC-P) is a distinct histologic entity that is believed to represent retrograde spread of invasive acinar adenocarcinoma into prostatic ducts and acini.We have analyzed the impact of IDC-P in hormonal naïve and castration resistant metastatic prostate cancer patients.Patients and methodsWe retrospectively evaluated 118 metastatic castration resistant prostate cancer (mCRPC) patients who were initially diagnosed with distant metastases from May 2010 to September 2018. Group 1 patients included 81 metastatic PCa patients with acinar adenocarcinoma and Group 2 included 37 metastatic PCa patients with IDC-P.ResultsMean age at presentation was 76 years (IQR 73.4-78.7) in group 1 and 74 years (68.5-80.6) in group 2. Mean PSA at diagnosis was 619 ng/mL (IQR 85-1113) and 868 ng/mL (IQR 186-1922), respectively. Time to castration resistance was 24.7 months (IQR 16.7-32.7) in group 1 and 10.2 months (IQR 4.2-16.2) in group 2 (p = 0.007). Time to progression in CPRC patients was: 10.6 months (IQR 5.6-15.6) and at 6.2 months (3.2-9.2), respectively (p = 0.05). Overall survival was 57.9 months in group 1(CI 95% 56.4-59.5) and 38 months (CI 95% 19.9-48.06) in group 2 (p = 0.001). In the multivariate analysis, adenocarcinoma subtype was statistically significant p 0.014, CI 95% (HR 0.058, 0.006-0.56).ConclusionsIDC-P seems to be a subtype of prostate cancer that is associated with a shorter response to hormonal treatment when compared to acinar adenocarcinoma in metastatic patients. New drugs in CRPC scenario as abiraterone and enzalutamide also obtained less response in IDC-P patients. In daily clinical practice it might be interesting to take into account that patients with IDC-P may present shorter responses to first and second line hormonal treatments. (AU)

Concomitant intraductal carcinoma of the prostate and response to hormonal therapy in metastatic prostate carcinoma.

INTRODUCTION AND OBJECTIVE: Most prostate cancers are classified as acinar adenocarcinoma. Intraductal carcinoma of the prostate (IDC-P) is a distinct histologic entity that is believed to represent retrograde spread of invasive acinar adenocarcinoma into prostatic ducts and acini. We have analyzed the impact of IDC-P in hormonal naïve and castration resistant metastatic prostate cancer patients. PATIENTS AND METHODS: We retrospectively evaluated 118 metastatic castration resistant prostate cancer (mCRPC) patients who were initially diagnosed with distant metastases from May 2010 to September 2018. Group 1 patients included 81 metastatic PCa patients with acinar adenocarcinoma and Group 2 included 37 metastatic PCa patients with IDC-P. RESULTS: Mean age at presentation was 76 years (IQR 73.4-78.7) in group 1 and 74 years (68.5-80.6) in group 2. Mean PSA at diagnosis was 619 ng/mL (IQR 85-1113) and 868 ng/mL (IQR 186-1922), respectively. Time to castration resistance was 24.7 months (IQR 16.7-32.7) in group 1 and 10.2 months (IQR 4.2-16.2) in group 2 (P = .007). Time to progression in CPRC patients was: 10.6 months (IQR 5.6-15.6) and at 6.2 months (3.2-9.2), respectively (P = .05). Overall survival was 57.9 months in group 1(CI 95% 56.4-59.5) and 38 months (CI 95% 19.9-48.06) in group 2 (P = .001). In the multivariate analysis, adenocarcinoma subtype was statistically significant P .014, CI 95% (HR 0.058, 0.006-0.56) CONCLUSIONS: IDC-P seems to be a subtype of prostate cancer that is associated with a shorter response to hormonal treatment when compared to acinar adenocarcinoma in metastatic patients. New drugs in CRPC scenario as abiraterone and enzalutamide also obtained less response in IDC-P patients. Once IDC-P is identified, clinicians could extrapolate the relative poor response to hormonal therapy. Consequently, follow-up of these patients in this scenario should be more strict.

Harmonic generation from gold nanolayers: bound and hot electron contributions to nonlinear dispersion.

Understanding how light interacts with matter at the nanoscale is pivotal if one is to properly engineer nano-antennas, filters and other devices whose geometrical features approach atomic size. We report experimental results on second and third harmonic generation from 20 nm- and 70 nm-thick gold layers, for TE- and TM-polarized incident light pulses. We discuss the relative roles that bound electrons and an intensity dependent free electron density (hot electrons) play in third harmonic generation. While planar structures are generally the simplest to fabricate, metal layers that are only a few nanometers thick and partially transparent are almost never studied. Yet, transmission offers an additional reference point to compare experimental measurements with theoretical models. Our experimental results are explained well within the context of the microscopic hydrodynamic model that we employ to simulate second and third harmonic conversion efficiencies. Using our experimental observations we estimate ∣χ1064nm(3)∣≈10-18 (m/V)2, triggered mostly by hot electrons.

Single-shot d-scan technique for ultrashort laser pulse characterization using transverse second-harmonic generation in random nonlinear crystals.

We demonstrate a novel dispersion-scan (d-scan) scheme for single-shot temporal characterization of ultrashort laser pulses. The novelty of this method relies on the use of a highly dispersive crystal featuring antiparallel nonlinear domains with a random distribution and size. This crystal, capable of generating a transverse second-harmonic signal, acts simultaneously as the dispersive element and the nonlinear medium of the d-scan device. The resulting in-line architecture makes the technique very simple and robust, allowing the acquisition of single-shot d-scan traces in real time. The retrieved pulses are in very good agreement with independent frequency-resolved optical grating measurements. We also apply the new single-shot d-scan to a terawatt-class laser equipped with a programmable pulse shaper, obtaining an excellent agreement between the applied and the d-scan retrieved dispersions.

Harmonic generation in the opaque region of GaAs: the role of the surface and magnetic nonlinearities.

Phase-locked second and third harmonic generation in the opaque region of a GaAs wafer is experimentally observed and analyzed both in transmission and reflection. These harmonic components, which are generated close to the surface, can propagate through an opaque material as long as the pump is tuned to a region of transparency or semitransparency and correspond to the inhomogeneous solutions of Maxwell's equations with nonlinear polarization sources. We show that measurement of the angular and polarization dependence of the observed harmonic components allows one to infer the different nonlinear mechanisms that trigger these processes, including not only the bulk nonlinearity but also the surface and magnetic Lorentz contributions, which usually are either hidden by the bulk contributions or assumed to be negligible. The experimental results are compared with a detailed numerical model that takes into account these different effects, including for the first time combined linear and nonlinear material dispersions in a nonlinear Lorentz oscillator model of the bulk nonlinearities. Our results suggest that the intensity of the second harmonic signal generated by the surface can be more intense than the signal generated by the bulk. These findings have significant repercussions and are consequential in nanoscale systems, which are usually investigated using only dispersionless bulk nonlinearities, with near-complete disregard of surface and magnetic contributions and their microscopic origins.

Reevaluation of radiation reaction and consequences for light-matter interactions at the nanoscale.

In the context of electromagnetism and nonlinear optical interactions, damping is generally introduced as a phenomenological, viscous term that dissipates energy, proportional to the temporal derivative of the polarization. Here, we follow the radiation reaction method presented in [Phys. Lett. A157, 217 (1991)], which applies to non-relativistic electrons of finite size, to introduce an explicit reaction force in the Newtonian equation of motion, and derive a hydrodynamic equation that offers new insight on the influence of damping in generic plasmas, metal-based and/or dielectric structures. In these settings, we find new damping-dependent linear and nonlinear source terms that suggest the damping coefficient is proportional to the local charge density and nonlocal contributions that stem from the spatial derivative of the magnetic field. We discuss the conditions that could modify both linear and nonlinear electromagnetic responses.

Comparative analysis of ferroelectric domain statistics via nonlinear diffraction in random nonlinear materials.

We present an indirect, non-destructive optical method for domain statistic characterization in disordered nonlinear crystals having homogeneous refractive index and spatially random distribution of ferroelectric domains. This method relies on the analysis of the wave-dependent spatial distribution of the second harmonic, in the plane perpendicular to the optical axis in combination with numerical simulations. We apply this technique to the characterization of two different media, Calcium Barium Niobate and Strontium Barium Niobate, with drastically different statistical distributions of ferroelectric domains.

Transverse single-shot cross-correlation scheme for laser pulse temporal measurement via planar second harmonic generation.

We present a novel single-shot cross-correlation technique based on the analysis of the transversally emitted second harmonic generation in crystals with random distribution and size of anti-parallel nonlinear domains. We implement it to the measurement of ultrashort laser pulses with unknown temporal duration and shape. We optimize the error of the pulse measurement by controlling the incident angle and beam width. As novelty and unlike the other well-known cross correlation schemes, this technique can be implemented for the temporal characterization of pulses over a very wide dynamic range (30 fs-1ps) and wavelengths (800-2200 nm), using the same crystal and without critical angular or temperature alignment.

Beam focalization in reflection from flat dielectric subwavelength gratings.

We experimentally demonstrate the recently predicted effect of near-field focusing for light beams from flat dielectric subwavelength gratings (SWGs). This SWGs were designed for visible light 532 nm and fabricated by direct laser writing in a negative photoresist, with the refractive index n=1.5 and the period d=314 nm. The laterally invariant gratings can focus light beams without any optical axis to achieve the transversal invariance. We show that focal distances can be obtained up to 13 µm at normal reflection for TE polarization.

Flat focusing mirror.

The control of spatial propagation properties of narrow light beams such as divergence, focusing or imaging are main objectives in optics and photonics. In this letter, we propose and demonstrate experimentally a flat focusing mirror, based on an especially designed dielectric structure without any optical axis. More generally, it also enables imaging any light pattern in reflection. The flat focusing mirror with a transversal invariance can largely increase the applicability of structured photonic materials for light beam propagation control in small-dimension photonic circuits.

Flat lensing in the visible frequency range by woodpile photonic crystals.

We experimentally demonstrate full two-dimensional focalization of light beams at visible frequencies by a three-dimensional woodpile photonic crystal. The focalization (the flat lensing) with focal distances of the order of 50-70 µm is experimentally demonstrated. Experimental results are compared with numerical calculations and interpreted by harmonic expansion studies.

Enhanced efficiency of the second harmonic inhomogeneous component in an opaque cavity.

In this Letter, we experimentally demonstrate the enhancement of the inhomogeneous second harmonic conversion in the opaque region of a GaAs cavity with efficiencies of the order of 0.1% at 612 nm, using 3 ps pump pulses having peak intensities of the order of 10 MW/cm(2). We show that the conversion efficiency of the inhomogeneous, phase-locked second harmonic component is a quadratic function of the cavity factor Q.

Valor del óxido nítrico nasal en el diagnóstico de la discinesia ciliar primaria / Value of nasal nitric oxide in the diagnosis of primary ciliary dyskinesia

Objetivo: Comunicar los valores de óxido nítrico nasal (ONn) en niños con discinesia ciliar primaria (DCP) comparados con los niveles de ONn en niños sanos y en niños afectos de asma, fibrosis quística (FQ) y bronquiectasias pos infecciosas. Pacientes y métodos: Se realizó la determinación de ONn en 9 niños con DCP, 36 niños asmáticos, 31 niños con FQ, 8 niños con bronquiectasias post infecciosas y 37 niños sanos. Se compararon los valores de ONn en las diferentes patologías y se determinó la sensibilidad y la especificidad de la prueba para el diagnóstico de DCP. Resultados: Todos los niños con DCP excepto uno (ONn 348 ppb) mostraron un valor de ONn inferior a 112 ppb, siendo la media de 88 ppb (IC95% 9,6–166). En los niños sanos, la media del ONn fue de 898 ppb (IC95% 801–995), en los asmáticos 1023 ppb (IC95% 911–1137), en los niños con FQ 438 ppb (IC95% 367–508) y en los pacientes con bronquiectasias pos infecciosas de 361 ppb (IC95% 252–470). El valor medio de ONn fue significativamente inferior (p<0,05) en los niños afectos de DCP respecto a todos los demás grupos. Un punto de corte de NOn ≤112 ppb mostró una sensibilidad del 88,9% y una especificidad del 99,1% para el diagnóstico de DCP [área bajo la curva ROC 0,98 (IC95% 0,94–0,99); p<0,0001; razón de probabilidad 95,1]. Conclusiones: Un valor de ONn ≤ 112 ppb en niños es altamente sugestivo de DCP aunque un valor superior no descarta por completo la enfermedad (AU)

Objective: The aim of this study is to report nasal nitric oxide (nNO) values in children with primary ciliary dyskinesia (PCD) and to compare them with nNO values in healthy children, asthmatic children, children with cystic fibrosis and children with post infectious bronchiectasis. Patients and methods: We determined nNO values in 9 children with PCD, 36 asthmatic children, 31 children with cystic fibrosis, 8 children with post infectious bronchiectasis and 37 healthy children. We compared nNO values between these different conditions and calculated sensitivity and specificity of nNO to diagnose PCD. Results: All children with PCD - except one (nNO 348 ppb) – had nNO values below 112 ppb, mean 88 ppb (95%CI 9.6–166). The nNO mean was 898 ppb (95%CI 801-995) in healthy children, 1023 ppb (95%CI 911–1137) in asthmatic children, 438 ppb (95%CI 367–508) in cystic fibrosis children and 361 ppb (95%CI 252–470) in children with post infectious bronchiectasis. The mean concentration of nNO was lower (P<0.05) in PCD patients, compared to the other groups. The measurement of nasal NO in our study population showed, at a cut-off level of ≤112 ppb, a sensitivity of 88.9% and a specificity of 99.1% in the diagnosis of PCD [ROC 0.98 (95%CI 0.94–0.99); P<0.0001; probability ratio 95.1]. Conclusions: The measurement of nasal NO appears to be a useful tool for screening children for PCD, in which a cut-off level of ≤112 ppb suggests the disease, although nNO above 112 ppb does not exclude PCD (AU)

The role of ferroelectric domain structure in second harmonic generation in random quadratic media.

We study theoretically and numerically the second harmonic generation in a nonlinear crystal with random distribution of ferroelectric domains. We show that the specific features of disordered domain structure greatly affect the emission pattern of the generated harmonics. This phenomena can be used to characterize the degree of disorder in nonlinear photonic structures.

[Value of nasal nitric oxide in the diagnosis of primary ciliary dyskinesia]. / Valor del óxido nítrico nasal en el diagnóstico de la discinesia ciliar primaria.

OBJECTIVE: The aim of this study is to report nasal nitric oxide (nNO) values in children with primary ciliary dyskinesia (PCD) and to compare them with nNO values in healthy children, asthmatic children, children with cystic fibrosis and children with post infectious bronchiectasis. PATIENTS AND METHODS: We determined nNO values in 9 children with PCD, 36 asthmatic children, 31 children with cystic fibrosis, 8 children with post infectious bronchiectasis and 37 healthy children. We compared nNO values between these different conditions and calculated sensitivity and specificity of nNO to diagnose PCD. RESULTS: All children with PCD - except one (nNO 348 ppb) - had nNO values below 112 ppb, mean 88 ppb (95%CI 9.6-166). The nNO mean was 898 ppb (95%CI 801-995) in healthy children, 1023 ppb (95%CI 911-1137) in asthmatic children, 438 ppb (95%CI 367-508) in cystic fibrosis children and 361 ppb (95%CI 252-470) in children with post infectious bronchiectasis. The mean concentration of nNO was lower (P<0.05) in PCD patients, compared to the other groups. The measurement of nasal NO in our study population showed, at a cut-off level of < or =112 ppb, a sensitivity of 88.9% and a specificity of 99.1% in the diagnosis of PCD [ROC 0.98 (95%CI 0.94-0.99); P<0.0001; probability ratio 95.1]. CONCLUSIONS: The measurement of nasal NO appears to be a useful tool for screening children for PCD, in which a cut-off level of < or =112 ppb suggests the disease, although nNO above 112 ppb does not exclude PCD.

Short-term variation in near-highway air pollutant gradients on a winter morning.

Quantification of exposure to traffic-related air pollutants near highways is hampered by incomplete knowledge of the scales of temporal variation of pollutant gradients. The goal of this study was to characterize short-term temporal variation of vehicular pollutant gradients within 200-400 m of a major highway (>150 000 vehicles/d). Monitoring was done near Interstate 93 in Somerville (Massachusetts) from 06:00 to 11:00 on 16 January 2008 using a mobile monitoring platform equipped with instruments that measured ultrafine and fine particles (6-1000 nm, particle number concentration (PNC)); particle-phase (>30 nm) [Formula: see text], [Formula: see text], and organic compounds; volatile organic compounds (VOCs); and CO(2), NO, NO(2), and O(3). We observed rapid changes in pollutant gradients due to variations in highway traffic flow rate, wind speed, and surface boundary layer height. Before sunrise and peak traffic flow rates, downwind concentrations of particles, CO(2), NO, and NO(2) were highest within 100-250 m of the highway. After sunrise pollutant levels declined sharply (e.g., PNC and NO were more than halved) and the gradients became less pronounced as wind speed increased and the surface boundary layer rose allowing mixing with cleaner air aloft. The levels of aromatic VOCs and [Formula: see text], [Formula: see text] and organic aerosols were generally low throughout the morning, and their spatial and temporal variations were less pronounced compared to PNC and NO. O(3) levels increased throughout the morning due to mixing with O(3)-enriched air aloft and were generally lowest near the highway reflecting reaction with NO. There was little if any evolution in the size distribution of 6-225 nm particles with distance from the highway. These results suggest that to improve the accuracy of exposure estimates to near-highway pollutants, short-term (e.g., hourly) temporal variations in pollutant gradients must be measured to reflect changes in traffic patterns and local meteorology.

Third-harmonic generation via broadband cascading in disordered quadratic nonlinear media.

We study parametric frequency conversion in quadratic nonlinear media with disordered ferroelectric domains. We demonstrate that disorder allows realizing broadband third-harmonic generation via cascading of two second-order quasi-phase matched nonlinear processes. We analyze both spatial and polarization properties of the emitted radiation and find the results in agreement with our theoretical predictions.

Synovial chondromatosis of the temporomandibular joint: CT and MRI findings.

We report a rare case of synovial chondromatosis of the temporomandibular joint (TMJ) in a 31-year-old man. CT examination showed a mixed soft tissue mass with small calcifications near the right TMJ joint space. MR images revealed a heterogeneous mass on the different sequences and, after contrast administration, originating in the right TMJ. Cytology showed chondroid cellularity. The lesion was surgically removed and final histological study demonstrated the diagnosis of a synovial chondromatosis. We highlight the importance of the complementary findings from CT and MR, especially the important specific feature described for TMJ synovial chondromatosis related to the mixed density within the mass, in order to perform an accurate preoperative diagnosis whenever there is an absence of ossified loose bodies.

[Immunohistochemical expression of p53, p21, p16, and cyclin D1 in superficial bladder cancer. A tissue microarray study]. / Expresión inmunohistoquímica de p53, p21, p16 y ciclina D1 en el cáncer de vejiga superficial. Estudio en un soporte de tissue microarray.

INTRODUCTION AND OBJECTIVES: To retrospectively assess the relationship between immunohistochemical expression of p53, p21, p16, and cyclin D1, with recurrence, progression and survival in superficial bladder cancer. METHODS: 163 patients undergoing transurethral resection for superficial bladder cancer between February 1995 and March 2004. Tumor samples were included in a tissue microarray support that was serially sectioned for immunohistochemical staining. Grade and stage associations for each marker were evaluated by the Chi-square test. Assessment of the relationship with recurrence, progression, and survival Kaplan-Meier curves and log-rank test were used. RESULTS: There were no statistically significant differences in marker expression depending on tumor grade and stage, with the exception of Cyclin D1, that was significantly different depending on tumor stage (p=0.030). p21 expression was related to tumor recurrence (p=0.035), progression (p=0.008) and survival (p=0.034). p16 expression was also related to recurrence (p=0.048) and survival (p=0.047), but not to tumor progression (p=0.116). p53 and Cyclin D1 were not statistically associated with tumor recurrence, progression or survival. CONCLUSIONS: In our experience, only p16 and p21 may be useful in the management of superficial bladder tumors, as they are predictors of recurrence and survival in Ta and T1 patients.