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OBJECTIVE: Eating disorders (EDs) often co-occur with social anxiety disorder (SAD). However, little research has examined the influence of SAD symptoms on ED treatment outcomes in the context of individual outpatient cognitive-behavior therapy for eating disorders (CBT-ED). It is plausible that SAD symptom severity could improve as a result of ED treatment, given the high overlap between EDs and SAD. We sought to test whether baseline SAD symptoms moderate early response to CBT-ED or post-treatment outcomes in CBT-ED, and the degree to which SAD symptoms improve during therapy despite SAD not being an explicit treatment target. METHOD: ED clients (N = 226) aged ≥16 years were treated with CBT-ED. Outcomes were ED symptoms, clinical impairment, and SAD symptoms measured at baseline, session 5 and post-treatment. RESULTS: Baseline SAD was a weak moderator of early and post-treatment ED symptoms and impairment. SAD symptoms improved moderately over treatment among clients who started with elevated levels of SAD symptomology. DISCUSSION: Clients with EDs can experience good therapeutic outcomes regardless of their social anxiety severity at pre-treatment. SAD symptoms reduced over CBT-ED, but protocol enhancements such as exposure-based strategies that directly target co-occurring social-evaluative concerns may help achieve larger reductions in SAD symptoms. PUBLIC SIGNIFICANCE: Eating disorders often co-occur with anxiety disorders such as social anxiety. We found people who had both social anxiety and an eating disorder benefited as much from eating disorder treatment as people who did not have social anxiety. People who were socially anxious became less anxious as a by-product of receiving eating disorder treatment. It may be possible to reduce social anxiety further by enhancing eating disorder treatment protocols.
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Terapia Cognitivo-Conductual , Trastornos de Alimentación y de la Ingestión de Alimentos , Fobia Social , Humanos , Terapia Cognitivo-Conductual/métodos , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Trastornos de Alimentación y de la Ingestión de Alimentos/psicología , Femenino , Adulto , Fobia Social/terapia , Fobia Social/psicología , Resultado del Tratamiento , Masculino , Adolescente , Adulto Joven , Persona de Mediana EdadRESUMEN
OBJECTIVE: Few studies have investigated the role of generic relational factors, such as group cohesion and working alliance, in group cognitive behaviour therapy (CBT) for social anxiety disorder (SAD). The aim of this study was to examine the temporal associations among working alliance, group cohesion, and an index of a CBT-specific factor, homework engagement, as correlates of fear of negative evaluation and symptoms of social anxiety in group CBT for SAD. METHOD: There were 105 participants with a diagnosis of social anxiety disorder who were randomly assigned to 12 sessions of group imagery-enhanced or standard CBT. Participants completed measures at various time points during the 12-session interventions, and the relationship among variables was examined through random-intercept cross-lagged panel models. RESULTS: Group cohesion was significantly associated with social anxiety symptoms at the end of treatment, however there was no significant relationship with working alliance. Greater homework engagement predicted lower social interaction anxiety, but only during mid-treatment. CONCLUSION: The results highlight the importance of supporting group cohesion and maximising homework engagement during core components of social anxiety treatment such as behavioural experiments.
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Terapia Cognitivo-Conductual , Fobia Social , Humanos , Fobia Social/terapia , Fobia Social/psicología , Cohesión Social , Terapia Cognitivo-Conductual/métodos , Trastornos de Ansiedad/terapia , Trastornos de Ansiedad/psicología , Ansiedad/terapia , Resultado del TratamientoRESUMEN
Trials of cognitive behaviour therapy (CBT) for social anxiety disorder (SAD) have struggled to identify replicable moderators of treatment outcome. This could be due to a genuine lack of effects, or a spurious finding caused by methodological factors such as inadequate testing of theory-driven moderators, use of small homogenous samples, failure to model non-linear relationships, and over-reliance on significance testing. We probed explanations for the field's failure to detect moderators by testing whether 15 theory-driven and atheoretical variables moderated treatment outcome in a large heterogeneous sample treated with group CBT for SAD. Moderation was not assessed by only using p-values for linear models, but also by considering effect sizes, plots, and non-linear relationships. Despite using a comprehensive approach to assess moderation, only two variables - the baseline severity of SAD symptoms and fear of negative evaluation (FNE) - were found to moderate social anxiety symptom trajectories. FNE had a non-linear relationship with symptom change that would have been missed using common research methods. Our findings suggest both a genuine lack of effects and limitations of research methods have contributed to the field's inability to identify moderators. We provide suggestions that may increase the likelihood of future researchers detecting genuine effects.
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Terapia Cognitivo-Conductual , Fobia Social , Humanos , Fobia Social/terapia , Trastornos de Ansiedad/psicología , Miedo , Terapia Cognitivo-Conductual/métodos , Resultado del Tratamiento , Ansiedad/psicologíaRESUMEN
Recurrent, negative self-imagery is common in social anxiety disorder (SAD). Imagery rescripting (ImRs) is an effective therapeutic technique that aims to target past aversive memories to modify their associated meanings, and update the encapsulated negative schematic beliefs. The current study aimed to extend previous research by investigating the cognitive and affective shifts during each phase of ImRs delivered within a group cognitive behavioral therapy protocol. Participants (Nâ¯=â¯32) retrieved an aversive memory associated with social anxiety and were guided through brief cognitive restructuring, prior to completing ImRs. Core beliefs associated with the memory (strength and valence) and fear of negative evaluation were assessed before and after ImRs and affect was assessed following each phase. Strength and affective valence of encapsulated core beliefs about the self, others, the world, and the image itself significantly reduced following ImRs, and core beliefs were updated to become more positive. Participants reported large affective shifts early in the process, with smaller shifts in the later stages. Fear of negative evaluation did not significantly reduce following ImRs. Outcomes provide some support for cognitive and affective changes during group ImRs for SAD and suggest future research directions to investigate longer-term impacts and to better understand the underlying mechanisms of the technique.
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Terapia Cognitivo-Conductual , Fobia Social , Cognición , Terapia Cognitivo-Conductual/métodos , Miedo/psicología , Humanos , Imágenes en Psicoterapia/métodos , Fobia Social/psicología , Fobia Social/terapia , Resultado del TratamientoRESUMEN
BACKGROUND: Cognitive behavior therapy (CBT) is effective for most patients with a social anxiety disorder (SAD) but a substantial proportion fails to remit. Experimental and clinical research suggests that enhancing CBT using imagery-based techniques could improve outcomes. It was hypothesized that imagery-enhanced CBT (IE-CBT) would be superior to verbally-based CBT (VB-CBT) on pre-registered outcomes. METHODS: A randomized controlled trial of IE-CBT v. VB-CBT for social anxiety was completed in a community mental health clinic setting. Participants were randomized to IE (n = 53) or VB (n = 54) CBT, with 1-month (primary end point) and 6-month follow-up assessments. Participants completed 12, 2-hour, weekly sessions of IE-CBT or VB-CBT plus 1-month follow-up. RESULTS: Intention to treat analyses showed very large within-treatment effect sizes on the social interaction anxiety at all time points (ds = 2.09-2.62), with no between-treatment differences on this outcome or clinician-rated severity [1-month OR = 1.45 (0.45, 4.62), p = 0.53; 6-month OR = 1.31 (0.42, 4.08), p = 0.65], SAD remission (1-month: IE = 61.04%, VB = 55.09%, p = 0.59); 6-month: IE = 58.73%, VB = 61.89%, p = 0.77), or secondary outcomes. Three adverse events were noted (substance abuse, n = 1 in IE-CBT; temporary increase in suicide risk, n = 1 in each condition, with one being withdrawn at 1-month follow-up). CONCLUSIONS: Group IE-CBT and VB-CBT were safe and there were no significant differences in outcomes. Both treatments were associated with very large within-group effect sizes and the majority of patients remitted following treatment.
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Terapia Cognitivo-Conductual , Fobia Social , Ansiedad , Trastornos de Ansiedad/terapia , Terapia Cognitivo-Conductual/métodos , Humanos , Fobia Social/psicología , Fobia Social/terapiaRESUMEN
Plasmonic photothermal therapy (PPTT), as an increasingly studied treatment alternative, has been widely regarded mostly as a surface tissue treatment choice. Although some techniques have been implemented for interstitial tumors, these involve some grade of invasiveness, as the outer skin is usually broken to introduce light-delivering optical fibers or even catheters. In this work, we present a potential non-invasive strategy using the stereotactic approach, long employed in radiosurgery, by converging multiple near infrared laser beams for PPTT in tissue-equivalent optical phantoms that enclose small gel spheres and simulate interstitial tissue impregnated with plasmonic nanoparticles. The real-time in-depth monitoring of temperature increase is realized by an infrared camera face-on mounted over the phantom. Our results show that a significant reduction in the surface heating can be achieved with this configuration while remarkably increasing the interstitial reach of PPTT, assuring a â¼6∘C temperature increase for the simulated tumors at 10 mm depth and â¼4∘C at 15 mm depth and opening up new possibilities for future clinical applications.
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Nanopartículas , Neoplasias , Oro , Humanos , Rayos Láser , Fantasmas de ImagenRESUMEN
BACKGROUND: The coronavirus pandemic (COVID-19) has required telehealth to be integrated into the delivery of evidence-based treatments for eating disorders in many services, but the impact of this on patient outcomes is unknown. OBJECTIVE: The present study examined the impact of the first wave of COVID-19 and rapid transition to telehealth on eating disorder symptoms in a routine clinical setting. METHOD: Participants were 25 patients with a confirmed eating disorder diagnosis who had commenced face-to-face treatment and rapidly switched to telehealth during the first wave of COVID-19 in Western Australia. Eating disorder symptoms, clinical impairment and mood were measured prospectively before and during lockdowns imposed due to COVID-19. HYPOTHESES: We predicted that patients would experience poorer treatment outcomes during COVID-19 and would perceive poorer therapeutic alliance and poorer quality of treatment compared to face-to-face therapy. RESULTS: Our hypotheses were not supported. On average, patients achieved large improvements in eating disorder symptoms and mood, and the magnitude of improvement in eating disorder symptoms was comparable to historical benchmarks at the same clinic. Patients rated the quality of treatment and therapeutic alliance highly. DISCUSSION: Providing evidence-based treatment for eating disorders via telehealth during COVID-19 lockdown is acceptable to patients and associated with positive treatment outcomes.
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COVID-19 , Prestación Integrada de Atención de Salud , Trastornos de Alimentación y de la Ingestión de Alimentos , Telemedicina , COVID-19/epidemiología , Trastornos de Alimentación y de la Ingestión de Alimentos/terapia , Humanos , Telemedicina/organización & administración , Resultado del Tratamiento , Australia Occidental/epidemiologíaRESUMEN
We present a new method to calculate the complex refractive index of spherical scatterers in a novel optical phantom developed by using homemade monodisperse silica nanospheres embedded into a polyester resin matrix and an ethanol-water mixture for applications in diffuse imaging. The spherical geometry of these nanoparticles makes them suitable for direct comparison between the values of the absorption and reduced scattering coefficients (µa and µs', respectively) obtained by the diffusion approximation solution to the transport equation from scattering measurements and those obtained by the Mie solution to Maxwell's equations. The values of the optical properties can be obtained by measuring, using an ultrafast detector, the time-resolved intensity distribution profiles of diffuse light transmitted through a thick slab of the silica nanosphere phantom, and by fitting them to the time-dependent diffusion approximation solution to the transport equation. These values can also be obtained by Mie solutions for spherical particles when their physical properties and size are known. By using scanning electron microscopy, we measured the size of these nanospheres, and the numerical results of µa and µs' can then be inferred by calculating the absorption and scattering efficiencies. Then we propose a numerical interval for the imaginary part of the complex refractive index of SiO2 nanospheres, ns, which is estimated by fixing the fitted values of µa and µs', using the known value of the real part of ns, and finding the corresponding value of Im(ns) that matches the optical parameters obtained by both methods finding values close to those reported for silica glass. This opens the possibility of producing optical phantoms with scattering and absorption properties that can be predicted and designed from precise knowledge of the physical characteristics of their constituents from a microscopic point of view.
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This paper discusses the main differences between two different methods for determining the optical properties of tissue optical phantoms by fitting the spatial and temporal intensity distribution functions to the diffusion approximation theory. The consistency in the values of the optical properties is verified by changing the width of the recipient containing the turbid medium; as the optical properties are an intrinsic value of the scattering medium, independently of the recipient width, the stability in these values for different widths implies a better measurement system for the acquisition of the optical properties. It is shown that the temporal fitting method presents higher stability than the spatial fitting method; this is probably due to the addition of the time of flight parameter into the diffusion theory.
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In this work we present an Autocorrelation z-scan technique to measure, simultaneously, the spatial and temporal distribution of femtosecond pulses near the focal region of lenses. A second-order collinear autocorrelator is implemented before the lens under test to estimate the pulse width. Signals are obtained by translating a Two Photon Absorption (TPA) sensor along the optical axis and by measuring the second-order autocorrelation trace at each position z. The DC signal, which is typically not considered important, is taken into account since we have found that this signal provides relevant information. Experimental results are presented for different lenses and input wavefronts.
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We describe the behavior of linearity in diffuse imaging by evaluating the differences between time-resolved images produced by photons arriving at the detector at different times. Two approaches are considered: Monte Carlo simulations and experimental results. The images of two complete opaque bars embedded in a transparent or in a turbid medium with a slab geometry are analyzed; the optical properties of the turbid medium sample are close to those of breast tissue. A simple linearity test was designed involving a direct comparison between the intensity profile produced by two bars scanned at the same time and the intensity profile obtained by adding two profiles of each bar scanned one at a time. It is shown that the linearity improves substantially when short time of flight photons are used in the imaging process, but even then the nonlinear behavior prevails. As the edge response function (ERF) has been used widely for testing the spatial resolution in imaging systems, the main implication of a time dependent linearity is the weakness of the linearity assumption when evaluating the spatial resolution through the ERF in diffuse imaging systems, and the need to evaluate the spatial resolution by other methods.
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Repetitive negative thinking (RNT) is a transdiagnostic process that serves to maintain emotional disorders. Metacognitive theory suggests that positive and negative metacognitive beliefs guide the selection of RNT as a coping strategy which, in turn, increases psychological distress. The aim of this study was to test the indirect effect of metacognitive beliefs on psychological distress via RNT. Patients (N=52) with primary and non-primary generalized anxiety disorder attended a brief, six-week group metacognitive therapy program and completed measures of metacognitive beliefs, RNT, and symptoms at the first and final treatment sessions, and at a one-month follow-up. Prospective indirect effects models found that negative metacognitive beliefs (but not positive metacognitive beliefs) had a significant indirect effect on psychological distress via RNT. As predicted by metacognitive theory, targeting negative metacognitions in treatment appears to reduce RNT and, in turn, emotional distress. Further research using alternative measures at multiple time points during therapy is required to determine whether the absence of a relationship with positive metacognitive beliefs in this study was a consequence of (a) psychometric issues, (b) these beliefs only being relevant to a subgroup of patients, or (c) a lack of awareness early in treatment.
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Trastornos de Ansiedad/terapia , Terapia Cognitivo-Conductual/métodos , Negativismo , Psicoterapia de Grupo/métodos , Pensamiento , Adulto , Trastornos de Ansiedad/psicología , Femenino , Humanos , Masculino , Metacognición , Estudios Prospectivos , Psicometría , Trastornos de Estrés Traumático Agudo/psicología , Trastornos de Estrés Traumático Agudo/terapia , Encuestas y CuestionariosRESUMEN
BACKGROUND: Generalized anxiety disorder (GAD) is a common and highly comorbid anxiety disorder characterized by repetitive negative thinking (RNT). Treatment trials tend to exclude individuals with non-primary GAD, despite this being a common presentation in real world clinics. RNT is also associated with multiple emotional disorders, suggesting that it should be targeted regardless of the primary disorder. This study evaluated the acceptability and effectiveness of brief group metacognitive therapy (MCT) for primary or non-primary GAD within a community clinic. METHODS: Patients referred to a specialist community clinic attended six, two-hour weekly sessions plus a one-month follow-up (N=52). Measures of metacognitive beliefs, RNT, symptoms, positive and negative affect, and quality of life were completed at the first, last, and follow-up sessions. RESULTS: Attrition was low and large intent-to-treat effects were observed on most outcomes, particularly for negative metacognitive beliefs and RNT. Treatment gains increased further to follow-up. Benchmarking comparisons demonstrated that outcomes compared favorably to longer disorder-specific protocols for primary GAD. LIMITATIONS: No control group or independent assessment of protocol adherence. CONCLUSIONS: Brief metacognitive therapy is an acceptable and powerful treatment for patients with primary or non-primary GAD.
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Trastornos de Ansiedad/psicología , Trastornos de Ansiedad/terapia , Terapia Cognitivo-Conductual/métodos , Negativismo , Aceptación de la Atención de Salud , Psicoterapia de Grupo/métodos , Adulto , Anciano , Ansiedad/psicología , Ansiedad/terapia , Emociones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud/psicología , Trastornos por Estrés Postraumático/psicología , Trastornos por Estrés Postraumático/terapia , Pensamiento , Resultado del TratamientoRESUMEN
A method for using liquid-crystal variable retarders (LCVRs) with continually varying voltage to measure the complete Mueller matrix of a general sample is presented. The LCVRs are usually employed with fixed retardance values due to the nonlinear voltage-retardance behavior that they show. For the measurement method presented here, the nonlinear voltage-retardance relationship is first measured, and then a linear fit of the known retardance terms to the detected signal is performed. For a gap of air, the measurement error in the Mueller-matrix polarimeter is estimated at 1%-10%, depending on the Mueller-matrix element. Also, we present experimental results for a Glan-Thompson prism polarizer as a test sample, and we use the measured Mueller parameters as functions of the orientation of the optical axes of the polarizer as an indication of the quality of the polarimeter. In addition, results are compared to a typical step-voltage method to measure the Mueller matrix. Both methods give good results.
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We present a theoretical analysis of the field distribution in the focal plane of a dispersionless, high numerical aperture (NA) aplanatic lens for an x-polarized short pulse. We compare the focused pulse spatial distribution with that of a focused continuous wave (CW) field and its temporal distribution with the profile of the incident pulse. Regardless of the aberration free nature of the focusing aplanatic lens, the temporal width of the focused pulse widens considerably for incident pulses with durations on the order of a few cycles due to the frequency-dependent nature of diffraction phenomena, which imposes a temporal diffraction limit for focused short pulses. The spatial distribution of the focused pulse is also affected by this dependence and is altered with respect to the diffraction limited distribution of the CW incident field. We have analyzed pulses with flat top and Gaussian spatial irradiance profiles and found that the focused pulse temporal widening is less for the Gaussian spatial irradiance pulse, whereas the spatial distribution variation is similar in both cases. We present results of the focused pulsewidth as a function of the NA for the two spatial irradiance distributions, which show that the Gaussian irradiance pulse outperforms the flat top pulse at preserving the incident pulse duration.
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We present a method for using liquid-crystal variable retarders (LCVR's) with continually varying voltage to measure the Stokes vector of a light beam. The LCVR's are usually employed with fixed retardance values due to the nonlinear voltage-retardance behavior that they show. The nonlinear voltage-retardance relationship is first measured and then a linear fit of the known retardance terms to the detected signal is performed. We use known waveplates (half-wave and quarter-wave) as devices to provide controlled polarization states to the Stokes polarimeter and we use the measured Stokes parameters as functions of the orientation of the axes of the waveplates as an indication of the quality of the polarimeter. Results are compared to a Fourier analysis method that does not take into account the nonlinear voltage-retardance relationship and also to a Fourier analysis method that uses experimental voltage values to give a linear retardance function with time. Also, we present results of simulations for comparison.
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We study femtosecond pulses at the focal plane of a perfectly conducting spherical mirror which is a dispersionless system, that is, it introduces no group velocity dispersion and no propagation time difference to the pulses after reflection. By using the scalar diffraction theory we will show that the neglected terms in the diffraction integral, when using the approximation of the bandwidth being smaller than the frequency of the carrier, have a significant influence on imaging if a laser pulse of a few femtoseconds is used in time-resolved imaging. The neglected terms introduce temporal spreading to extremely short pulses of a few optical cycles incident on the mirror, which avoids a fully compensated pulse, i.e., a one optical cycle pulse, at the focus of the mirror. The study in this paper also applies to refracting optical systems such as microscope objectives or lenses.
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Cognitive Behavioural Group Therapy (CBGT) for social phobia has been shown to be efficacious within research units and effective within a variety of real world clinical settings. However, most effectiveness studies of CBGT for social phobia have (a) used protocols without demonstrated efficacy, (b) not included direct comparison groups, and/or (c) contained features of efficacy trials. This study addressed these limitations by using a benchmarking strategy to compare outcomes from the same CBGT protocol used in both a research unit and a community clinic. Research (N = 71) and community (N = 94) patients completed the same 12-session protocol, which resulted in significant reductions in social anxiety and life interference at post-treatment. Compared to research unit patients, community patients had more severe symptoms and life interference at pre-treatment, and were more likely to be male, use medication, have comorbid disorders, and have lower educational attainment. Importantly, degree of improvement on social anxiety symptoms and life interference did not differ across the treatment settings for either completer or intention-to-treat analyses. There was some evidence that being younger, single, and having a depression diagnosis were associated with dropout. Pre-treatment symptoms and number of diagnoses predicted post-treatment symptoms. Consistent with previous uncontrolled trials, it is concluded that CBGT is effective within community mental health clinics.
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Benchmarking/métodos , Terapia Cognitivo-Conductual/métodos , Trastornos Fóbicos/rehabilitación , Adulto , Servicios Comunitarios de Salud Mental , Femenino , Humanos , Masculino , Factores de Riesgo , Conducta Social , Resultado del TratamientoRESUMEN
We analyze the spatiotemporal intensity of pulses with durations of 20 fs and shorter and a carrier wavelength of 810 nm at the paraxial focal plane of an achromatic doublet lens. The incident pulse is well-collimated, and we use the Seidel aberration theory for thin lenses to evaluate the phase change due to the aberrations of the lens. In a set of cemented thin lenses with the stop at the lens, there is only spherical aberration, coma, astigmatism and field curvature, whereas the distortion aberration in the phase front is zero. We analyze the effect of these aberrations in the focusing of ultrashort pulses for homogenous illumination. We will show that the temporal spreading introduced by these aberrations in pulses shorter than 20 fs at 810 nm is very small but the spatial spreading is not, which reduces the intensity of the pulse considerably.
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We analyze the spatiotemporal intensity of Gaussian temporal envelope pulses with initial durations of 200 fs and a carrier wavelength of 810 nm at the paraxial focal plane of an achromatic doublet lens for a well-collimated incoming pulse beam by using the Seidel aberration theory for thin lenses with the stop at the lens. We analyze the effect of these aberrations in the focusing of ultrashort pulses for Gaussian illumination and present experimental results for 200 fs pulses focused by a near-IR achromatic doublet.