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El pie equino en niños produce un patrón de marcha inestable e ineficiente y un inadecuado posicionamiento en silla de ruedas. El tratamiento mediante ciclo de yesos seriados mantiene el rango de movimiento, facilitando el desarrollo de patrones de movimiento normales. Su uso combinado con toxina botulínica tiene efectos beneficiosos demostrados, pero faltan pautas para establecer el protocolo de tratamiento óptimo.

In this paper a sliding-mode yaw moment controller and fuzzy logic wheel slip controller are proposed to enhance vehicle stability in a split-μmanoeuvre. The proposed wheel slip controller shows good performance in improving vehicle handling in a braking manoeuvre. However, when a braking manoeuvre was conducted under the split-μcondition, the yaw moment generated by the asymmetric braking forces may cause the vehicle-handling stability to deteriorate. The sliding-mode yaw moment controller was introduced to regulate the wheel slip controller to improve the vehicle-handling performance. A target slip allocation algorithm was employed to coordinate the control conflict between the anti-lock braking system and vehicle stability control. First, the proposed control system was evaluated through pure computer simulation and a hardware in-the-loop simulation system. Then an experimental test was also introduced to verify the effectiveness of the proposed control system.

An agent-based integrated control framework is proposed to organize the active steering, active driveline, active brake, and anti-lock braking—acceleration slip regulation controllers, which traditionally have been relatively independent. Analysis is made of the characteristics of vehicle-handling dynamics, the functions of the individual controllers, and their interrelationships. A coordination mechanism is employed to manage interdependences and conflicts among the subcontrollers, so as to improve the flexibility, adaptability, and robustness of the global control system. The trade-off between yaw rate tracking, lateral stability, and longitudinal acceleration tracking is considered in the coordination. The control subsystems and the agent-based integrated control architecture are implemented in MATLAB/Simulink to study the vehicle-handling capability under critical manoeuvring conditions. Simulation results show that the proposed intelligent and flexible control framework is predominant in organizing the subsystems, and could provide better performance than the stand-alone controllers for the vehicle longitudinal and lateral motion.

Background & Aims: Few studies have explored risk factors predicting hepatitis C virus (HCV) infection in blood donors; their results are contradictory. The aim of this study was to evaluate the association between HCV infection and various risk factors in Canadian volunteer blood donors. Methods: Four transfusion centers were involved in this case-control study. A total of 267 confirmed anti-HCV-positive blood donors were interviewed along with 1068 seronegative blood donors matched for sex, age, donation site, and date. Information was collected using a structured telephone interview. The main outcome measures were odds ratios (ORs) and 95% confidence intervals (CIs) for various risk factors from univariate and multivariate analyses using conditional logistic regression. Results: By univariate analysis, 23 variables were associated with anti-HCV positivity. In the final multivariate analysis, only 5 factors remained independently predictive of HCV infection: previous intravenous drug use (OR, 127.5; 95% CI, 26.0-625.0), having lived in a prison or juvenile detention center (56.1; 11.4-275.7), previous blood transfusion (10.5; 4.7-23.2), sexual contact with an intravenous drug user (6.9; 3.1-15.2), and tattooing (5.7; 2.5-13). Conclusions: Most blood donors acquire infection by percutaneous exposure to contaminated blood. A role for sexual transmission is suggested by this study. GASTROENTEROLOGY 1999;116:893-899

A program of immunization against hepatitis B, consisting of one dose of hepatitis B immune globulin within 12 hours of birth and three doses of hepatitis B vaccine at 0, 1, and 6 months of age for all infants of carrier mothers, has been operating in British Columbia, Canada, since 1984. The authors report on a survey conducted in 1992 of children immunized between 1984 and 1989. The survey included blood tests obtained from the children and interviews of the mothers. A total of 770 of 1,135 eligible children participated. Thirty-one percent of the mothers had been positive for hepatitis B e antigen prior to the birth of the child. At follow-up, the overall antibody against hepatitis B surface antigen seropositivity rate for children was 87.9 percent. A total of 5.1 percent of children had evidence of previous hepatitis B infection, and 2.3 percent were hepatitis B surface antigen positive. In multiple logistic regression analysis, a delay in the initial dose of vaccine was associated with increased risk of infection, but the age of the child was not, even though antibodies against hepatitis B surface antigen declined with age. The authors conclude that most infections occurred early and resulted from prenatal infection, initial nonresponse, or a delay in the initial dose of vaccine, not from waning immunity. A booster dose of vaccine, at least up to age 8 years, is not necessary.

Four cases of T cell neoplasia are reported: three presenting as T cell acute lymphoblastic leukemia and one presenting in the leukemic phase of a T cell lymphoma. In all cases, the cells of the leukemic clone were characterized by an identical cytogenetic abnormality. This abnormality was a unique reciprocal translocation involving chromosomes 10 and 14. The breakpoint in chromosome 14 was in band q11, coincident with the assigned locus of the alpha-chain gene of the T cell antigen receptor. The breakpoint in chromosome 10 was in band q24, a region reported to include the locus of the terminal deoxynucleotidyltransferase (TdT) gene. Our observations suggest that translocation t(10;14)(q24;q11) is specific for T cell neoplasia and that a gene in chromosomal band 10q24, possibly the TdT gene, plays an important role in T cell neoplasia when its expression or coding sequence is altered by aberrant recombination involving a T cell antigen receptor gene.