Today, there are many commercial CAM systems available capable of generating NC codes for milling free-form geometries up to 5-axis. However, the quality of these NC codes has not yet been well discussed so far. Apparently, on the computer screen and the geometrical simulation provided by CAM, tool paths calculated by different CAM systems seem to be the same. However, as observed in this work, NC codes differ expressively according to the CAM software applied, and it affects the productivity and quality of the machined surface. Thus, a study was carried out to investigate this issue. A representative workpiece with free-form geometries was designed; a data acquisition system from an open architecture CNC was developed and NC codes were generated by five worldwide commercial CAM systems. The finishing milling operation was evaluated. The results presented difference of up to 30% on the real machining time, differences in the feed rate oscillation and up to 2 times the surface roughness value. This work reveals an essential limitation on the CAM algorithm and arises a new point for benchmarking CAM systems, which brings an opportunity to improve the calculation of tool paths for milling free-form geometries.

In June 2009, the World Health Organization declared a novel influenza A, S-OIV (H1N1), pandemic. We observed 44 consecutive patients during the "first wave" of the pandemic. 70.5% of them showed co-morbidities (hypertension, obesity, chronic respiratory diseases, chronic renal disease, diabetes, pregnancy). Serious cases were admitted to the intensive care unit (ICU), particularly those with severe acute respiratory failure. Some of them developed acute kidney injury (AKI) and required renal replacement therapy (RRT). The average time between admission to the ICU and initiation of RRT was 3.16 ± 2.6 days. At initiation of RRT, most patients required mechanical ventilation. No relationship was found with creatinine-kinase levels. Seventy-five percent of the cases were observed during a 3-week period and mortality, related to respiratory failure, doubling of alanine amino transferase and use of inotropics was 81.8%. In conclusion, the H1N1-infected patients who developed RRT-requiring AKI, in the context of multi-organ failure, showed a high mortality rate. Thus, it is mandatory that elaborate strategies aimed at anticipating potential renal complications associated to future pandemics are implemented.

Un aspecto importante para el control automático de la frecuencia es la medición del coeficiente de amortiguamiento de la carga (estatismo); pues conociendo su valor, se puede calcular con precisión el factor BIAS, fundamental para una calibración eficiente de un Sistema Automático de Control de la Generación (AGC). En la literatura especializada se dan valores típicos del coeficiente de amortiguamiento de la carga y se dice que debe estar entre 1 y 2%. En el presente artículo se describe un método para medir este coeficiente en el Sistema Nacional Interconectado (SNI) del Ecuador, en diferentes horarios del día.

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Management of prematures in the NICU has reduced neonatal mortali ty and morbidity; however, deficits in cognitive and sensory functioninq persist. The environment of the NICU may be responsible for newly recognized iatrogenic problems and may not be conductive for optimal development. We studied the quantity, quality, organization, and diurnal rhythmicity of physical and social stimulation in the NICU. Observations were conducted every half hour over 3 days. Physical recordings included light and sound levels, sound spectra, and occurrence of nonspeech, speech, and radio sounds. This information was collected both in the units and in incubators. Social data included the frequency of nursing care, feeding, social touching, rocking, and talking when in contact with an infant. There were 405 recordings for each physical var: iable and 1551 infant observations. The same illumination was always present. Infants were exposed incessantly to nonspeech sounds. Sound levels at times were excessively high. Incubators did not shield infants from stimulation. 19% of the observations included social contact of which 17% involved handling. Infants in the NICU suffered not from a lack of visual auditory, and tactile stimulation, but from a low frequency of sensory coordinated experiences. There was no diurnal rhythmicity in the physical or Retrospective studies have implicated fetal head constraint a s one cause for sagittal, coronal and metopic craniostenosis, Early sutural patency is contingent on persistent dural growth stretch. We bypothesize that fetal head constraint in a particular plane is one mechanism through which one or more sutural regions may be relieved of growth stretch, enhancing the liability towards synostosis at that region. This hypothesis is supported by animal studies and we present sutural histology fran 15 instances of sagittal craniostenosis for which gestational histories implicated fetal head constraint as the cause in 13 instances. We also present histology frcm 2 constraint-related cases of metopic craniostenosis. In each case there was ectocranial bone deposition, endocranial bone resorption and demnstrable sutural synostosis. A Sayers partial calvariectany procedure was performed at or before 6 ms. in all instances. This dramatically restored head shape to normal with refonnation of the palvarium and sutures. This sutural histology and restoration to normal form by surgery differed from that found in 6 instances of coronal craniostenosis which occured as part of a broader pattern of intrinsic malformation, such as Pfeiffer or Saethre-Chotzen synclromes. In these latter instances, the altered craniofacial form tended to persist despite early calvariectany. Maximal decreased in serum bilirubin levels were observed at I 457.9 and 488.0 nanometers with significantly less change observed at 476.5 and 514.5 nanometers (P<0.05). These data confirm the maximal effect of "blue light" but the action spectrum appears not to be identical to the absorption spectrum of protein-bound bilirubin. Rather, it exte...

Se presentan los resultados de seguridad y evolución clínica de 87 pacientes que recibieron plasma de convaleciente en la sala de Clínica Médica del Hospital Argerich en Buenos Aires. Tres pacientes tuvieron sobrecarga de volumen. Hubo 33 pases a Terapia Intensiva (37,9%) y 21 casos requirieron asistencia respiratoria mecánica (24,1%). Fallecieron 18 pacientes (20,7%). Tres de ellos por limitación del esfuerzo terapéutico y 15 en Terapia Intensiva. La mortalidad en Terapia Intensiva fue del 45,4%. Hubo solo 10 casos que recibieron plasma dentro de las 72 horas del comienzo de síntomas: de ellos, 1 caso de asistencia respiratoria y 1 fallecido; entre 72 horas y una semana recibieron plasma 25 casos con 26,9% de asistencia respiratoria y 20% de mortalidad, y de los 50 pacientes que recibieron mas allá de la primera semana, 25,4% requirieron de asistencia respiratoria y 24% fallecieron. Nuestra serie no pudo demostrar efecto beneficioso en la administración temprana de plasma y no fue diseñada para medir eficacia. El procedimiento fue bien tolerado en la gran mayoría de los pacientes.