Platelet-rich fibrin in rhinoplasty: A precise and standardized approach.

Rhinoplasty is a complex procedure. To achieve the expected aesthetic result, surgeons often use grafts both for structural and camouflage purposes. The perfect camouflage graft should be soft, malleable and precisely tailored to the patient's needs, with as few donor sites as possible. The use of diced cartilage has been widely described, but it cannot be used as a free graft in all cases. Platelet-rich fibrin is an interesting matrix for the creation of soft grafts with great precision and high reproducibility while promoting biocellular regeneration via growth factors. This article describes the use of platelet-rich fibrin in liquid and solid forms for the creation of standardized soft grafts with diced cartilage. We detail the procedure, and present the different grafts created by the author for dorsal camouflage and augmentation, tip management, and revision rhinoplasty.

Reconciling solar and stellar magnetic cycles with nonlinear dynamo simulations.

The magnetic fields of solar-type stars are observed to cycle over decadal periods-11 years in the case of the Sun. The fields originate in the turbulent convective layers of stars and have a complex dependency upon stellar rotation rate. We have performed a set of turbulent global simulations that exhibit magnetic cycles varying systematically with stellar rotation and luminosity. We find that the magnetic cycle period is inversely proportional to the Rossby number, which quantifies the influence of rotation on turbulent convection. The trend relies on a fundamentally nonlinear dynamo process and is compatible with the Sun's cycle and those of other solar-type stars.

Recovery time of independent poststroke life habits: Part II.

The purposes of this study were to determine the time of the recovery of poststroke life habits and to identify prognostic indicators associated with recovery time among stroke patients in a rehabilitation program. A sample of 421 stroke patients who were admitted to a rehabilitation center was recruited from medical records available from January 1987 to December 1992. The relation between the achievement of independent life habits including bed mobility, transfers and ambulation, bathing activities, dressing activities, eating activities, home activities, sphincter control, and sleep with the potential covariates associated with recovery time was assessed through the analysis of survival data using the Cox maximum-likelihood proportional hazard models. The poststroke life habits obtained generated mean recovery times ranging from 5.51 to 57.60 days from admission to rehabilitation. The survival analysis revealed that the recovery time of the selected poststroke abilities was significantly influenced (p <.05) by one or several indicators; these included physical ability and neuropsychological and life habit characteristics. With this precious information, stroke rehabilitation specialists may be able to reduce the length of time required to recover independent poststroke life habits by treating the specific neuropsychological, physical, and life habit characteristics identified in this study. A faster poststroke recovery would reduce the socioeconomic impact generated by stroke disability and would also ensure a better quality of life to the stroke survivor.

Recovery time of independent poststroke abilities: Part I.

The purposes of this study were to determine the time of the recovery of poststroke abilities and to identify prognostic indicators associated with recovery time among stroke patients undergoing a rehabilitation program. A sample of 421 stroke participants admitted to a rehabilitation center was recruited from medical records that were available from January 1987 to December 1992. The mean age was 61.8 years (range, 17-89 years). The relationship between the achievement of independent poststroke abilities and the potential covariates associated with recovery time was assessed through the analysis of survival data. Cox maximum-likelihood proportional hazard models were used for the analysis. Independent poststroke abilities included behavior, cognitive, perceptual, communication, visual, and motor status. The time from rehabilitation admission to complete independence was introduced to the model in relation to the covariates. The mean time of recovery of poststroke abilities ranged from 18.70 to 32.40 days from the rehabilitation admission. The survival analysis revealed that the time of recovery of the selected poststroke abilities was significantly influenced (p <.05) by one or several factors, among these were neuropsychological, physical, and life habits. With this precious information, stroke rehabilitation specialists may be able to reduce the length of time required to recover independent poststroke abilities by treating the specific neuropsychological, physical, and life habit characteristics identified in this study. A faster poststroke recovery will reduce the socioeconomic impact generated by stroke disability and will ensure a better quality of life to the stroke survivor.