The brain deformation that occurs during neurosurgery is a serious issue impacting the patient "safety" as well as the invasiveness of the brain surgery. Model-driven compensation is a realistic and efficient solution to solve this problem. However, a vital issue is the lack of reliable and easily obtainable patient-specific mechanical characteristics of the brain which, according to clinicians' experience, can vary considerably. We designed an aspiration device that is able to meet the very rigorous sterilization and handling process imposed during surgery, and especially neurosurgery. The device, which has no electronic component, is simple, light and can be considered as an ancillary instrument. The deformation of the aspirated tissue is imaged via a mirror using an external camera. This paper describes the experimental setup as well as its use during a specific neurosurgery. The experimental data was used to calibrate a continuous model. We show that we were able to extract an in vivo constitutive law of the brain elasticity: thus for the first time, measurements are carried out per-operatively on the patient, just before the resection of the brain parenchyma. This paper discloses the results of a difficult experiment and provide for the first time in vivo data on human brain elasticity. The results point out the softness as well as the highly non-linear behavior of the brain tissue.

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Utilizando un modelo micro-fundamentado de tres sectores para una pequeña economía abierta, se analiza la interdependencia entre la tasa de cambio real estructural (definida como el cociente entre el precio de los bienes transables y el de los no transables) y la tasa de desempleo, aplicándolo al caso de Argentina. Los resultados empíricos sugieren una relación negativa y significativa entre el tipo de cambio real estructural y la tasa de desempleo, lo cual indicaría que frente a una apreciación del tipo de cambio real se puede producir un efecto del tipo enfermedad holandesa - contrayendo el sector productor de manufacturas - afectando negativamente las oportunidades de crecimiento y empleo en el largo plazo.

This research analyses the inertia and persistence of headline and sectoral inflation for Argentina (two periods), Brazil and Chile using seasonal fractional integrated autoregressive moving average (S-ARFIMA model). Measuring inertia by the sum of the autoregressive coefficients, there is evidence of: (i) headline, clothing, health, housing and miscellaneous inertial inflation larger in Argentina (second period) than in Chile and Brazil, (ii) inertial inflation of food and beverages is larger for Chile than for Argentina (second period) and Brazil, and (iii) inertial inflation of education larger in Brazil than in Chile, which in turn is larger than in Argentina (second period). Measuring persistence by the size of the fractionally integrated coefficient, our results suggest long-memory or long-dependence of Brazilian headline, clothing and health inflation, and Chilean alcoholic beverages. We show also that the quarter-life of headline inflation occurs in 20, 3 and 15 months in Argentina (second period), Brazil and Chile, while its half-life takes 29, 15 and 13 months, respectively.