Parenteral nutrition in oncologic patients]

A B16 melanoma-specific CD8+ T cell line (AB1) was established from the spleen cells of C57BL/6 mice cured of B16 melanoma with interleukin (IL)-12 treatment. The AB1 line exclusively used T cell receptor Vbeta11. The AB1 cells exhibited a cytolytic activity against both syngeneic B16 melanoma and allogeneic P815 mastocytoma, whereas a cold inhibition assay revealed specificity of the AB1 cells against B16 melanoma. Their lostability to kill a class I loss variant of B16 melanoma was restored by the transfection of H-2Kb gene. In addition, their interferon (IFN)-gamma production was significantly suppressed by the addition of anti-H-2Kb monoclonal antibody, and RT-PCR analysis showed that the AB1 line expressed the mRNA encoding IFN-gamma, but not IL-4 or IL-10. The experiment using synthetic peptides of tyrosinase-related protein-2 (TRP-2) revealed that the AB1 cells could recognize TRP-2(181-188) peptide. Moreover, the AB1 cells showed an in vivo antitumor effect against established pulmonary metastases of B16 melanoma. Overall, these results indicate that the Tc1-type Vbeta11+ AB1 cells exert an antitumor activity against syngeneic B16 melanoma through recognition of TRP-2(181-188) peptide in an H-2Kb-restricted manner.     

Energy-efficient design of a presbyopia correction wearable powered by mobile GPUs and FPGAs

The Journal of Supercomputing - This paper presents an energy-efficient design and evaluation of a novel portable device for the automatic correction of presbyopia in human eyes driven by the use...     

LiveROMS: A virtual environment for ocean numerical simulations

LiveROMS is a bootable DVD that contains an Linux-based computer operating system which has a complete, functioning version of the ROMS ocean circulation model and an Octave version of ROMSTOOLS. It allows students and scientists to experiment with this ocean numerical model, with just a basic knowledge of Linux.     

Corneal wave aberration from videokeratography: accuracy and limitations of the procedure

A procedure to calculate the wave aberration of the human cornea from its surface shape measured by videokeratography is presented. The wave aberration was calculated as the difference in optical path between the marginal rays and the chief ray refracted at the surface, for both on- and off-axis objects. The corneal shape elevation map was obtained from videokeratography and fitted to a Zernike polynomial expansion through a Gram-Schmidt orthogonalization. The wave aberration was obtained also as a Zernike polynomial representation. The accuracy of the procedure was analyzed. For calibrated reference surface elevations, a root-mean-square error (RMSE) of 1 to 2 microm for an aperture 4-6 mm in diameter was obtained, and the RMSE associated with the experimental errors and with the fitting method was 0.2 microm. The procedure permits estimation of the corneal wave aberration from videokeratoscopic data with an accuracy of 0.05-0.2 microm for a pupil 4-6 mm in diameter, rendering the method adequate for many applications.     

Antiproteinuric effect of angiotensin-converting enzyme inhibition and C5b-9 urinary excretion in membranous glomerulonephritis

BACKGROUND: Angiotensin-converting enzyme (ACE) inhibitors have an antiproteinuric effect in membranous glomerulonephritis (MGN). However, no studies have investigated whether this antiproteinuric effect is influenced by urinary C5b-9 excretion, a marker of immunological activity in this disease. METHODS: Eleven patients with biopsy-proven MGN were treated with captopril for 8 weeks. The evolution of several clinical and biochemical parameters, including 24-h urinary protein excretion was evaluated every 4 weeks. Urinary C5b-9 excretion was measured at the onset and at the end of captopril treatment. RESULTS: Patients with MGN had significantly higher C5b-9 excretions than a group of 14 healthy controls (89 +/- 23 vs 3.7 +/- 1.4 ng/mg UCr; P < 0.001). A significant correlation was found between urinary C5b-9 and the magnitude of proteinuria, both at the onset and at the end of treatment. After 8 weeks of captopril treatment, proteinuria had decreased from 8 +/- 1.8 to 5.2 +/- 1.3 g/day (P < 0.05). Four weeks after captopril discontinuation, proteinuria rose to 7.3 +/- 1.7 g/day (P < 0.05). A marked variability in the antiproteinuric response was observed, ranging from 0 to 85% with respect to baseline values. No correlation between decrease in proteinuria and baseline urinary C5b-9 levels was observed. Several patients with elevated urinary C5b-9 levels had captopril-induced decrease in proteinuria. CONCLUSIONS: ACE inhibition induces an antiproteinuric effect in patients with MGN. The urinary C5b-9 excretion does not predict the magnitude of this response.     

Refraction, aliasing, and the absence of motion reversals in peripheral vision

Reversals in perceived direction of motion of a grating when its spatial frequency exceeds half that of the sampling mosaic provide a potential tool for estimating sampling frequency in peripheral retina. We used two-alternative forced-choice tasks to measure performance of three observers detecting or discriminating direction of motion of high contrast horizontal or vertical sinusoidal luminance gratings presented either 20 or 40 deg from the fovea along the horizontal meridian. A foveal target at a comfortable viewing distance aided fixation and accommodation. A Maxwellian view optometer with 3 mm artificial pupil was used to correct the refraction of the peripheral grating, which was presented in a circular patch, 1.8 deg in diameter, in a surround of similar colour and mean luminance (47.5 cd.m-2). The refractive correction at each eccentricity was measured by recording the aerial image of a point after a double pass through the eye. The highest frequency which can reliably be detected (7-14 c/deg at 20 deg, 5.5-7.5 c/deg at 40 deg) depends critically on refraction. Refraction differs by up to 5 D from the fovea to periphery, and by up to 6 D from horizontal to vertical. Direction discrimination performance shows no consistent reversals, and depends less on refraction. It falls to chance at frequencies as low as one-third of the highest that can be detected. Gratings which can be detected but whose direction of motion cannot be discriminated appear as irregular speckle patterns whose direction of motion varies from trial to trial.(ABSTRACT TRUNCATED AT 250 WORDS)     

Directional light scanning laser ophthalmoscope

The cone photoreceptor mosaic of the living human eye has in a limited number of cases been imaged without the use of wavefront-correction techniques. To accomplish this, the directionality of the photoreceptors, as manifested by their waveguiding properties, may be used to advantage. In the present paper we provide a model of our recently proposed directional light scanning laser ophthalmoscope [Opt. Lett. 29, 968 (2004)] together with a detailed numerical analysis of the device. The outcome is compared with experimental results.     

Wideband uniplanar 180° phase switch

A wideband 180° phase switch is developed at millimetre-wave frequencies (31 GHz centre frequency) using uniplanar technology. The circuit is designed using coplanar-to-slotline transitions and commercial pin diodes as switching devices. The implementation is straightforward, fast in terms of fabrication and low-cost. The circuits tested, made on an alumina substrate, show a phase difference between states of 180° ± 2°, providing 40% bandwidth with in-band insertion loss lower than 2.5 dB and a return loss better than 10 dB. The phase switch provides a ±5° phase error in a bandwidth of around 60%, from 18 to 38 GHz.     

Dynamic eye model for adaptive optics testing

An artificial dynamic eye model is proposed. The prototype enabled us to introduce temporal variations in defocus and spherical aberration, resembling those typically found in the human eye. The eye model consisted of a meniscus lens together with a modal liquid crystal lens with controllable focus. A diffuser placed at a fixed distance from the lenses acted as the artificial retina. Developed software allowed the user to precisely control the dynamic generation of aberrations. In addition, different refractive errors could simultaneously be emulated by varying the distance between the components of the model. The artificial eye was first used as a dynamic generator of both spherical aberration and defocus, imitating the behavior of a real eye. The artificial eye was implemented in an adaptive optics system designed for the human eye. The system incorporated an electrostatic deformable mirror and a Hartmann-Shack wavefront sensor. Results with and without real time closed-loop aberration correction were obtained. The use of the dynamic artificial eye could be quite useful for testing and evaluating adaptive optics instruments for ophthalmic applications.     

High power-added efficiency MMIC amplifier for 2.4 GHz wirelesscommunications

This work describes the design and the measured performance of a high-efficiency monolithic microwave integrated circuit (MMIC) amplifier for wireless communications in the 2.4 GHz band. The monolithic technology employed in the circuit integration is based on standard 0.5-μm-gate-length MESFET. The design procedure is based on load-cycle graphic optimization of the transistor performance. On-wafer experimental characterization shows output power up to 24 dBm and excellent results of power-added efficiency up to 79% with 19.5 dBm output power at low drain bias voltage. The amplifier performance achieved and the circuit size, which is 1 mm², are suitable for use in the transmitter chains of wireless communication systems in the 2.4 GHz band