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SIGNIFICANCE: A variety of subjective and objective procedures are available to measure the amplitude of accommodation. However, it is unclear whether the standard criterion of Hofstetter's minimum minus 2 D can be used to diagnose accommodative insufficiency with each of these techniques. PURPOSE: The use of objective dynamic retinoscopy and three subjective techniques to diagnosis accommodative insufficiency was examined. METHODS: A total of 632 subjects between 8 and 19 years of age were enrolled. Accommodative lag, monocular accommodative facility, and subjective (push-up, modified push-down, and minus lens) and objective (dynamic retinoscopy) amplitude of accommodation were quantified. Accommodative insufficiency was diagnosed based on Hofstetter's minimum minus 2 D for each subjective method, as well as adding an additional subjective criterion (either accommodative lag exceeding 0.75 D or monocular accommodative facility falling below the age-expected norms). RESULTS: The prevalence of accommodative insufficiency was lowest and highest with the push-up (7.9 and 1%) and dynamic retinoscopy (94 and 12%) procedures when measured without and with the additional subjective criteria, respectively. Comparing the validity of dynamic retinoscopy against the traditional criterion, moderate to low sensitivity and high specificity were found. However, adding the additional subjective criteria improved the findings with moderate to high sensitivity and high specificity. Using a cutoff for dynamic retinoscopy of 7.50 D showed moderate diagnostic accuracy based on likelihood ratios. CONCLUSIONS: It is clear that a revised definition of accommodative insufficiency is required, which must include the method of assessing accommodation. The various objective and subjective methods for quantifying the amplitude of accommodation are not interchangeable, and subjective assessment does not provide a valid measure of the accommodative response.

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Lead is one of the 10 most toxic chemicals of greatest concern for its effects on public health. Predominantly, in undeveloped countries, high blood lead levels (BLLs) persist in the population. To develop intervention strategies that may reduce lead exposure in populations, it is a priority to know the sources of lead pollution. The objective of this critical review and meta-analysis is to assess whether there is an association between different sources of lead exposure and the mean difference in blood lead levels in people exposed. To identify the major lead source exposure, a statistical analysis was performed on selection studies. This investigation reveals the limited information available on the sources of lead in Mexico and other lead producer countries, such as Croatia, Ecuador, Brazil, South Korea, India, Nigeria, Turkey, and China. Meta-analysis could be performed only in battery, smelting mining, and glazed ceramic workers. Battery manufacturing workers have the highest mean difference level of lead in their blood worldwide. Mexico has the second highest mean difference BLL in battery workers in the world. An interesting difference between the mean difference in BLL in mining workers from uncontrolled industry (-39.38) and controlled industry (-5.68) was found. This difference highlighted the success of applying strict control of lead sources and community education to reduce BLL and its potential harmful effects on human health and the environment. Children living near mining sites have the highest mean difference BLL (-11.1). This analysis may aid in assessing the source of lead exposure associated with a range of BLLs in people. Furthermore, this review highlights several social and cultural patterns associated with lead exposure and lead levels in control populations. These results could help to develop international lead regulations and appropriate public health guidelines to protect people around the world.

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Understanding behavioral systems as emergent systems comprising the environment and organism subsystems, include spatial dynamics as a primary dimension in natural settings. Nevertheless, under the standard approaches, the experimental analysis of behavior is based on the single response paradigm and the temporal distribution of discrete responses. Thus, the continuous analysis of spatial behavioral dynamics is a scarcely studied field. The technological advancements in computer vision have opened new methodological perspectives for the continuous sensing of spatial behavior. With the application of such advancements, recent studies suggest that there are multiple features embedded in the spatial dynamics of behavior, such as entropy, and that they are affected by programmed stimuli (e.g., schedules of reinforcement) at least as much as features related to discrete responses. Despite the progress, the characterization of behavioral systems is still segmented, and integrated data analysis and representations between discrete responses and continuous spatial behavior are exiguous in the experimental analysis of behavior. Machine learning advancements, such as t-distributed stochastic neighbor embedding and variable ranking, provide invaluable tools to crystallize an integrated approach for analyzing and representing multidimensional behavioral data. Under this rationale, the present work (1) proposes a multidisciplinary approach for the integrative and multilevel analysis of behavioral systems, (2) provides sensitive behavioral measures based on spatial dynamics and helpful data representations to study behavioral systems, and (3) reveals behavioral aspects usually ignored under the standard approaches in the experimental analysis of behavior. To exemplify and evaluate our approach, the spatial dynamics embedded in phenomena relevant to behavioral science, namely, water-seeking behavior and motivational operations, are examined, showing aspects of behavioral systems hidden until now.

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Los tumores cardíacos primarios son poco frecuentes y representan solo el 5% de todos los tumores cardíacos. El 75% de estos tumores son benignos, y el mixoma es el tumor benigno más común en el adulto (50%). La mayoría de los mixomas cardíacos se localizan en la aurícula izquierda, solo el 18-20% se localizan en la aurícula derecha, y es aún más infrecuente la aparición de un tumor bilobulado, los signos y síntomas con los que se presentan son inespecíficos y varían de acuerdo a su comportamiento. Presentamos un caso con estas características en una paciente escolar de 9 años de edad que ingresó al Hospital del Niño Manuel Ascencio Villarroel

Primary cardiac tumors are rare and represent only 5% of all cardiac tumors. 75% of these tumors are benign, and myxoma is the most common benign tumor in adults (50%). Most cardiac myxomas are located in the left atrium, only 18-20% are located in the right atrium, and the appearance of a bilobed tumor is even more infrequent, the signs and symptoms with which they occur are nonspecific and they vary according to their behavior. We present a case with these characteristics in a 9-year-old school patient who was admitted to Manuel Ascencio Villarroel Children's Hospital.

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The control of magnetic materials and devices by voltages without electric currents holds the promise of power-saving nano-scale devices. Here we study the temperature-dependent voltage control of the magnetic anisotropy caused by rare-earth (RE) local moments at an interface between a magnetic metal and a non-magnetic insulator, such as Co|(RE)|MgO. Based on a Stevens operator representation of crystal and applied field effects, we find large dominantly quadrupolar intrinsic and field-induced interface anisotropies at room temperature. We suggest improved functionalities of transition metal tunnel junctions by dusting their interfaces with rare earths.

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Nonequilibrium systems exhibit particle-type solutions. Oscillons are one of the best-known localized states of systems with time-dependent forcing or parametrically driven systems. We investigate the transition from nonradiative to radiative oscillons in the parametrically driven sine-Gordon model in two spatial dimensions. The bifurcation takes place when the strength of the forcing (frequency) increases (decreases) above a certain threshold. As a result of this transition, the oscillon emits radially symmetric evanescent waves. Numerically, we provide the phase diagram and show the supercritical nature of this transition. For small oscillations, based on the amplitude equation approach, the sine-Gordon equation with time-dependent forcing is transformed into the parametrically driven damped nonlinear Schrödinger model in two spatial dimensions. This amplitude equation exhibits a transition between nonradiative to radiative localized structures, consistently. Both models show quite good agreement.

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It has been reported in non-contingent schedules that the variety of patterns of behavior is affected by the temporal variation of water deliveries. While temporal variation is accomplished by delivering water at fixed or variable times, spatial variation is usually accomplished by varying the number of dispensers and distance among them. Such criteria do not consider the possible ecological relevance of the location of water dispensers. Nevertheless, it is plausible to suppose that the intersection of the programed contingencies (e.g., time-based schedules), the ecological differentiated space (e.g., open vs. closed zones), and the relative location of relevant objects and events (e.g., location of the water source-peripherical vs. center zone) could set up an integrated system with the behavioral patterns of the organism. In the present study, we evaluated the eco-functional relevance of two locations of the dispensers upon behavioral dynamics in Wistar rats using fixed and variable time schedules in a modified open-field system. In Experiment 1, three subjects were exposed to a fixed time 30-s water delivery schedule. In the first condition, the water dispenser was located at the center of the experimental chamber. In the second condition, the water dispenser was located at the center of a wall of the experimental chamber. Each location was present for 20 sessions. In Experiment 2, conditions were the same, but a variable time schedule was used. Routes, distance to the dispenser, recurrence patterns, time spent in zones, entropy, and divergence were analyzed. Our findings suggest a robust differential relevance of the location of the dispensers that should be considered in studies evaluating behavioral dynamics. Results are discussed from an integrative, ecological-parametric framework.

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The magnetization dynamics of nano-oscillators may be excited by both magnetic fields and spin-polarized currents. While the dynamics of single oscillators has been well characterized, the synchronization of several ones is not fully understood yet. An analytical and numerical study of the nonlinear dynamics of two magnetostatically coupled spin valves driven by spin-transfer torques is presented under the macrospin approximation. The oscillators interact via magnetostatic fields and exhibit a robust synchronized magnetization motion. We describe the magnetization dynamics of the system using the Landau-Lifshitz-Gilbert-Slonczewski equation. Using a modal decomposition technique, we describe the dynamics, synchronization, and competition of oscillatory modes as a function of the current density, and the geometrical parameters of the setup. Simulations of the Landau-Lifshitz-Gilbert-Slonczewski equation show good agreement with an approximate analytic solution.

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Abstract Studies on conditional discrimination (CD) in humans have pointed out that linguistic contact with the properties and criteria of the task is critical both for acquisition and transfer, especially in extra-relational and extra-dimensional tests. Recent empirical and conceptual analyses have challenged this assumption. Studies in the field have generally included linguistic components, but the effect of linguistic restriction through tasks that compete with verbal activity regarding tasks, such as linguistic interference, has not yet been systematically explored. Two experiments were conducted: the first one used first-order matching-to-sample tasks (FOMST) and the second used second-order matching-to-sample tasks (SOMST), aiming to evaluate the effect of a linguistic interference task on the acquisition of conditional discrimination and functional adjustment in transfer tests (extra-instance, extra-modal, extra-relational, and extra-dimensional). Both experiments used an n = 1 design. A total of 24 college students participated, 12 in each study, and the effects of two experimental conditions were tested (Interference and No Interference, with six participants in each condition per study). The findings suggest that interference in linguistic contact does not affect the acquisition of CD in FOMST or in SOMST, but it does affect the adjustment in transfer tests. In these, differential effects, by type, were observed in FOMST and SOMST.

Resumo No estudo da discriminação condicional (DC) em humanos, tem-se descrito que o contato linguístico com as propriedades e os critérios da tarefa tem uma grande importância para a aquisição e a transferência dela, especialmente para os testes de tipo extrarrelacional e extradimensional. Contudo, estudos empíricos e conceituais recentes questionam essa suposição. Em estudos prévios, têm se acrescido componentes linguísticos, mas não se tem explorado sistematicamente o efeito de sua restrição por meio de tarefas que compitam com a atividade verbal a respeito de tarefas como a interferência linguística. Neste estudo, realizaram-se duas experiências -uma com tarefas de igualação de primeira ordem (Timpo) e outra com tarefas de segunda ordem (Timso)- com o objetivo de avaliar o efeito da interferência linguística sobre a aquisição de uma DC e sobre o ajuste funcional em testes de transferência (extrainstância, extramodal, extrarrelacional e extradimensional). Nas duas experiências, utilizou-se um desenho N = 1, do qual participaram 24 estudantes universitários no total -12 em cada estudo-, e contrastaram-se os efeitos de duas condições experimentais: uma com interferência e outra sem interferência -com seis participantes para cada condição-. Os achados sugerem que a interferência no contato linguístico não afeta a aquisição da DC nem em Timpo nem em Timso, mas sim afeta o ajuste em testes de transferência, pois nestes se observam efeitos diferenciais por tipo tanto em Timpo quanto em Timso.

Resumen En el estudio de la discriminación condicional (DC) en humanos se ha descrito que el contacto lingüístico con las propiedades y criterios de la tarea tiene una gran importancia para la adquisición y la transferencia de la misma, especialmente para las pruebas de tipo extrarrelacional y extradimensional. Sin embargo, estudios empíricos y conceptuales recientes cuestionan dicho supuesto. En estudios previos se han agregado componentes lingüísticos, pero no se ha explorado sistemáticamente el efecto de su restricción a través de tareas que compitan con la actividad verbal con respecto a tareas, como la interferencia lingüística. En el presente estudio se realizaron dos experimentos -uno con tareas de igualación de primer orden (TIMPO) y otro con tareas de segundo orden (TIMSO)- con el objetivo de evaluar el efecto de la interferencia lingüística sobre la adquisición de una DC y en el ajuste funcional en pruebas de transferencia (extrainstancia, extramodal, extrarrelacional y extradimensional). En los dos experimentos se utilizó un diseño N = 1, en el que participaron 24 estudiantes universitarios en total -doce en cada estudio-, y se contrastaron los efectos de dos condiciones experimentales: una con con interferencia y otra sin interferencia -con seis participantes para cada condición-. Los hallazgos sugieren que la interferencia en el contacto lingüístico no afecta la adquisición de la DC ni en TIMPO ni en TIMSO, pero sí afecta el ajuste en pruebas de transferencia, pues en estas se observaron efectos diferenciales por tipo, tanto en TIMPO como en TIMSO.

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OBJECTIVE: In this article we present a set of different visualizations of Mexico's nanomedicine scientific production data. METHOD: Visualizations were developed using different methodologies for data analysis and visualization such as social network analysis, geography of science maps, and complex network communities analysis. RESULTS: Results are a multi-dimensional overview of the evolution of nanomedicine in Mexico. Moreover, visualizations allowed to identify trends and patterns of collaboration at the national and international level. Trends are also found in the knowledge structure of themes and disciplines. Finally, we identified the scientific communities in Mexico that are responsible for the new knowledge production in this emergent field of science.

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PURPOSE: Dynamic retinoscopy (DR) is a procedure for assessing the accommodative response using a standard clinical instrument. The present study compared measurements of the amplitude of accommodation (AA) obtained using this technique with two subjective methods (modified push-down and minus lens). Additionally, the expected ranges for AA when measured by DR were determined. METHOD: AA was measured in 1298 subjects between 5 and 60 years of age using the three techniques described above. Subjects were grouped into 5-year bins, and a descriptive univariate analysis of the data performed. Goodness-of fit plots were constructed to examine the overall model fit. Centile curves were calculated from the final model. RESULTS: Mean values of AA obtained using DR were significantly lower than for the two subjective techniques. For the DR findings, no significant change was observed between 5 and 19 years of age (mean AA = 8.3 D) and between 45 and 60 years of age (mean AA = 0.6 D). AA values as a function of age were best fit by the polynomial regression equation: logAA = 1.93 + 0.49(age) - 0.19(age)(2) . CONCLUSION: Measurements of AA determined using DR are significantly lower than the normative subjective findings published previously. This difference is at least partly due to the depth-of-field of the eye. These norms markedly overestimate accommodative responsivity. DR provides a simple technique for quantifying accommodation in the clinical setting.

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BACKGROUND: Mescal production is the main economic activity associated to agaves in Mexico, which involves 53 species mostly harvested from forests. The increasing mescal demand has influenced risk in both agave populations and mescal production, but other social and ecological factors also intervene. We hypothesized that the greater the risk the greater the complexity of management responses; otherwise, the greater the probability of populations' depletion. We analysed this hypothesis by examining the diversity of risk conditions and management practices of Agave inaequidens in the state of Michoacán, in central-western Mexico. METHODS: We studied five communities of Michoacán, documenting through 41 semi-structured interviews the use forms, risk perception, number of agaves annually extracted, and the management practices. Using a matrix with social-ecological and technological data analyzed by PCA, we evaluated similarities of management contexts. A data matrix with information on risk of agave populations, and other about management practices were analysed also through CCA and PCA. The scores of the first principal components were considered as indexes of risk and management complexity, respectively. A regression analysis of these indexes evaluated their relation. RESULTS: We recorded 34 different uses of A. inaequidens, the most important being mescal production (mentioned by 76.1 % of people interviewed). Nearly 12.5 % of people practice only gathering, but others mentioned the following practices: Selective let standing of agaves for seed production (20 %); in situ transplanting of saplings; seed propagation in nurseries and saplings transplanting to forest (10 %); suckers transplanting (7.5 %); seed dispersal in forests; banning (5 %); enhancing of agave growth by removing tree canopies (2.5 %); transplanting from the wild to live fences (45 %); intensive plantations (35 %). The highest vulnerability of agave populations was identified in communities where risk is not counteracted by management. In two communities we identified the highest risk (annual extraction from 4,353 to 6,557 agaves), but different actions counteracting such risk. CONCLUSIONS: Interchange of knowledge and management experiences developed by handlers is crucial for the regional conservation, recovering, and sustainable management of A. inaequidens populations.

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Macroscopic systems with dissipation and time-modulated injection of energy, parametrically driven systems, can self-organize into localized states and/or patterns. We investigate a pulse that travels over a one-dimensional pattern in parametrically driven systems. Based on a minimal prototype model, we show that the pulses emerge through a subcritical Andronov-Hopf bifurcation of the underlying pattern. We describe a simple physical system, a magnetic wire forced with a transverse oscillatory magnetic field, which displays these traveling pulses.

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Se evaluó el efecto de cuatro modos de contacto (directo, morfología lingüística, observacional y directo más descripción) sobre la adquisición y transferencia de una discriminación condicional y la generación de descripciones tipo regla. Participaron dieciséis universitarios experimentalmente ingenuos, con edades entre 18 y 21 años. Se utilizó un diseño intragrupo con prueba inicial, entrenamiento, tarea de generación de regla y pruebas de transferencia (extrainstancia, extramodal y extrarrelacional), con igualación a la muestra de segundo orden como tarea experimental base. Los resultados sugieren que: a) tanto el modo observacional -sin componentes instrumentales- como el de morfología lingüística -sin contacto perceptual directo con los arreglos- permiten la adquisición y transferencia de la discriminación condicional, así como la emergencia de reglas; y b) no hay una relación consistente entre la emergencia de reglas y la transferencia extrarrelacional efectiva. Los resultados se discuten en torno a la necesidad de: a) contacto directo con las contingencias para la transferencia y la emergencia de reglas, b) participación de un segmento lingüístico (i.e. regla) para la transferencia extrarrelacional efectiva.

This study examined the effect of four contact modes (direct, morphology, linguistic, observational, and direct plus description) on the acquisition and transfer of conditional discrimination and the emergence of rules. Sixteen experimentally naive university students, aged between 18 and 21 years, participated in the study. A within-subject design that involved initial test, training, rule generation, and testing transfer (extra instance test, extra modal test, extra relational test) was used. A second order matching to sample task was used. The results suggest that: a) both the observational mode without instrumental components and the linguistic morphology without direct perceptual contact allow the acquisition and transfer of conditional discrimination and the emergence of rules; b) there is no consistent relationship between the rules and the effective extrarelational transfer. Results are discussed in terms of the need for: i) direct contact with contingencies for the transfer and emergence of rules, ii) participation of a linguistic segment (rule) for the effective extrarelational transfer.

Avaliou-se o efeito de quatro modos de contato (direto, morfologia linguística, observacional e direto mais descrição) sobre a aquisição e transferência de uma discriminação condicional e a geração de descrições tipo regra. Participaram dezesseis universitários experimentalmente ingênuos, com idades entre 18 e 21 anos. Utilizou-se um desenho intragrupo com teste inicial, treinamento, tarefa de geração de regra e testes de transferência (extra instância, extra modal e extra relacional), com igualação à mostra de segunda ordem como tarefa experimental base. Os resultados sugerem que: a) tanto o modo observacional -sem componentes instrumentais- como o de morfologia linguística -sem contato perceptual direto com os arranjos- permitem a aquisição e transferência da discriminação condicional, bem como a emergência de regras; e b) não há uma relação consistente entre a emergência de regras e a transferência extra relacional efetiva. Os resultados discutem-se ao redor da necessidade de: i) contato direto com as contingências para a transferência e a emergência de regras, ii) participação de um segmento linguístico (ex. regra) para a transferência extra relacional efetiva.

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Macroscopic magnetic systems subjected to external forcing exhibit complex spatiotemporal behaviors as result of dissipative self-organization. Pattern formation from a uniform magnetization state, induced by the combination of a spin-polarized current and an external magnetic field, is studied for spin-transfer nano-oscillator devices. The system is described in the continuous limit by the Landau-Lifshitz-Gilbert equation. The bifurcation diagram of the quintessence parallel state, as a function of the external field and current, is elucidated. We have shown analytically that this state exhibits a spatial supercritical quintic bifurcation, which generates in two spatial dimensions a family of stationary stripes, squares, and superlattice states. Analytically, we have characterized their respective stabilities and bifurcations, which are controlled by a single dimensionless parameter. This scenario is confirmed numerically.

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Introducción: La acondroplasia es la condición más común asociada a una estatura baja con grave desproporción anatómica. Las complicaciones de la vía respiratoria difícil constituyen una de las causas más frecuente de su morbilidad y mortalidad, entre las que se pueden citar: macroglosia, escasa apertura bucal, presencia de una tráquea estrecha, limitación en la movilidad cervical, problemas pulmonares crónicos, mandíbula pequeña con aglomeración de la dentadura y mentón prominente. Objetivo: Describir la conducta anestésica de una paciente obstétrica acondroplásica con vía respiratoria difícil. Caso Clínico: Paciente del sexo femenino, de 20 años de edad, con diagnóstico de acondroplasia y asma bronquial. Embarazo gemelar de 34 semanas el cual le imposibilitaba la deambulación, la sostenibilidad, dificultad respiratoria y no tolerancia del decúbito supino. Se le practicó cesárea, abordaje de vía respiratoria difícil, intubación con máscara laríngea Fastrach colocación de tubo endotraqueal # 6.0, ventilación controlada adecuada, utilización de relajantes musculares no despolarizantes, estabilización hemodinámica intraoperatoria, recuperación. Se trasladó a Sala Recuperación Anestésica sin complicaciones. Alta médica a los 10 días de hospitalización. Conclusiones: El abordaje de la vía respiratoria de las pacientes con Acondroplasia constituye un enigma para los anestesiólogos, pero la discusión multidisciplinaria y la ejecución de un plan de actuación favoreció el buen resultado del binomio madre-feto.

Introduction: The achondroplasia is the commonest condition associated with a low height with a severe anatomical disproportion. The complications of the difficult airway are one of the more frequent cause of morbility and mortality including: macroglossia, an scarce buccal aperture, presence of a narrow trachea, limitation of cervical mobility, chronic pulmonary problems, small mandible with teeth crowding and a prominent chin. Objective: To describe the anesthetic behavior of an obstetrics patient with achondroplasia and a difficult airway. Clinical case: A female patient aged 20 diagnosed with achondroplasia and bronchial asthma. A twin pregnancy of 34 weeks avoiding her to walk, to stand up, respiratory difficulty and no tolerance of supine decubitus. She undergoes a cesarean section, approach of the difficult airway, intubation with a Fastrach laryngeal mask, placement of the #6.0 endotracheal tube, appropriate controlled ventilation, use of non-depolarizing muscle relaxants, intraoperative hemodynamic stabilization, recovery. She was transferred to Anesthesia Recovery Ward with complications, was discharged at 10 days of hospitalization. Conclusions: The approach of the airway of patients with achondroplasia is an enigma for anesthesiologists, but the multidisciplinary discussion and the performance of action plan favored the good result of mother-fetus duo.

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Introducción: El síndrome de Stevens-Johnson tiene una evolución grave, a menudo fatal. Se considera como una variedad de eritema multiforme en su forma ampollar cutáneo-mucosa. Su comienzo es repentino. Caso Clínico: Se presenta una paciente de 35 años de edad, de la raza negra, que ingresó en el Hospital Provincial Ginecobstétrico "Ana Betancourt de Mora" de la ciudad de Camagüey, hospitalización realizada por protocolo de la institución. Con diagnóstico de Síndrome de Steven Johnson como variante severa de un mes de evolución e infección por el virus de la inmunodeficiencia humana (VIH), la cual presentaba embarazo a término de 39,2 semanas que comenzó en trabajo de parto, con pruebas de bienestar fetal idóneas, anunciada para intervención quirúrgica cesárea de urgencia. La conducción anestésica de los pacientes con síndrome de Stevens-Johnson es generalmente difícil y más aún cuando se asocia con la infección por el virus de VIH en una parturienta. Se decidió método anestésico regional peridural. Conclusiones: Se detallan las particularidades anatómicas de la vía aérea potencialmente difícil, así como la evolución intra y posoperatoria. Ante una paciente obstétrica con estas entidades los cuidados anestésicos constituyen hoy un reto para los anestesiólogos.

Introduction: The Stevens-Johnson syndrome has a severe evolution sometimes fatal. It is considered as a variety of the multiform erythema in its form cutaneous-mucosa ampulla. Its onset is sudden. Clinical case: This is the case of a black female patient aged 35 admitted in the "Ana Betancourt de Mora" Gynecology and Obstetrics Hospital of Camagüey province, admission carried out according to the protocol of the institution. She was diagnosed with Stevens -Johnson syndrome as a severe variant of one month of evolution and infection by human immunodeficiency virus (HIV) and a term pregnancy of 39,2 weeks starting in labor with suitable fetal wellbeing tests, programmed for an urgent cesarean section. The anesthesia conduction of patients with Stevens-Johnson Syndrome is generally difficult and more even when it is associated with HIV infection in a pregnant woman. The peridural regional anesthesia method was choosen. Conclusions: The anatomical distinctive features of the potentially difficult airway are detailed, as well as the intraoperative and postoperative evolution. In presence of a pregnant patient with these entities the anesthesia cares are nowadays a challenge for anesthesiologists.

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PURPOSE: Dynamic retinoscopy (DR) is an objective technique for assessing maximum accommodative responsivity. The present study examined the test-retest reliability of this procedure when measuring the amplitude of accommodation (AA). METHODS: In the first trial, the within-session repeatability of the AA was measured in 79 subjects between 18 and 30 years of age using DR and two subjective procedures, namely the modified push-down (MPD) and minus lens (ML) techniques. Data were collected by two different examiners. In a second trial, the inter-session repeatability of the AA was assessed in 76 subjects by a single evaluator with a time interval of 7 days between the first and second sessions. The repeatability, reproducibility and agreement between the methods were determined using the mean difference, 95% limits of agreement, intraclass correlation coefficient and concordance correlation coefficient. RESULTS: DR showed the lowest mean value of AA in each trial (average for the two trials = 7.44 D) while the equivalent mean values for the MPD and ML techniques were 9.84 and 9.43 D, respectively. Further, DR showed the best repeatability in both the repeatability trials and poorer inter-examiner agreement was observed for the MPD and ML procedures. The concordance correlation coefficient for DR-MPD, DR-ML and MPD-ML procedures were 0.32, 0.33 and 0.62, respectively for the within-session trial and 0.31, 0.36 and 0.76, respectively for the inter-session trial. CONCLUSION: The DR technique provides a more veridical measurement of the AA because it avoids the overestimation resulting from the depth-of-field. Moreover, the DR technique exhibited higher reproducibility, when compared with subjective methods. These differences may be important when evaluating accommodative dysfunctions or monitoring accommodative therapy. The fact that the DR procedure can be performed using standard clinical equipment makes this a valuable technique both for vision screening programs and routine eye care.

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