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Owing to load variation and unmodeled dynamics, a robot manipulator can be classified as a nonlinear dynamic system with structured and unstructured uncertainties. In this paper, the stability and robustness of a class of the fuzzy logic control (FLC) is investigated and a robust FLC is proposed for a robot manipulator with uncertainties. In order to show the performance of the proposed control algorithm, computer simulations are carried out on a simple two-link robot manipulator.

Penetrating craniocerebral firearm injuries remain one of the most lethal causes of all trauma and are common both in war or peace time. Data were reviewed for 4140 severely head-injured patients (Glasgow Coma Scale (GCS) scores 3-8) treated at Xi-Jing Hospital between 1973 and 1993; 51 of these patients had acute penetrating craniocerebral injuries caused by firearm missiles. These patients consisted of 46 males (90.2%) and 5 females (9.8%) ranging in age from 3 months to 48 years (median 22.4 years). The lesion types included 2 tangential wounds, 37 tubular wounds and 12 through-and-through wounds. All cases were urgent with the patients in severe and unstable states. After emergency treatment and operation, 5 cases died (9.8%). Follow up studies at three months showed that 23 cases (45.1%) had made a good recovery. Moderate disability, severe disability and vegetative states in this series were 29.4%, 13.7% and 2.0% respectively. Long term follow up studies indicated that 32 were able to resume their occupation. The principles for managing penetrating craniocerebral firearm injuries and suggestions for operation are discussed.

Ursolic acid (UA) and oleanolic acid (OA) were examined for anti-angiogenic activities by using the chick embryo chorioallantoic membrane (CAM) assay. The presence of UA or OA inhibited angiogenesis in a dose-dependent manner; the doses required for half-maximal inhibition (ID50) were 5 micrograms and 40 micrograms per CAM, respectively. UA was a more potent angiogenic inhibitor than OA. We also tested for inhibitory effect on the proliferation of bovine aortic endothelial cell. They effectively inhibited the proliferation of bovine aortic endothelial cell in a concentration-dependent manner. The IC50 values of anti-proliferative effects were determined to be 5 microM for UA and 20 microM for OA. Based on these results, we speculated that the inhibitory effects on bovine aortic endothelial cell proliferation of UA and OA might be important for anti-angiogenesis.

We used the method of RIA determined the contents of atrial natriuretic peptide (ANP), angiotensin II (ANG II) in plasma and brain tissues after brain injury in 70 rats. The results showed that the ANP was significantly decreased in brain tissues on 6, 72 hours after brain injury. At the same time, the plasma and brain tissues ANG II, brain water contents were significantly increased. The results suggested that the unbalance of ANP and ANG II may be related to the pathophysiological process of brain edema.

We used 46 rabbits for the study of blood-brain barrier (BBB) permeability quantitatively in early-stage brain injury by a dropping weight method. The animals were divided into two groups: control group and brain injury group. Both Evans' blue and colloidal gold (CG) particles were utilized for evaluation of BBB permeability alteration. Three different sizes of CG 5, 10 and 15 nm in diameter were employed as tracers for a quantitative investigation of BBB changes by light and electron microscopes respectively. In addition, the brain water contents were determined. The preliminary data indicated that an increase of BBB permeability began 30 minutes after the injury with a few of 5 or 10 nm CG particles present in the endocytic pits and endothelial microvilli, and the augmentation of BBB permeability reached its peak 6 hours after the injury. More CG tracers penetrated into the precapillary arterioles, venules or capillaries through the opening of tight junctions of BBB and by vesicular transportation. The variation of the brain water contents was closely correlated to the above-mentioned BBB changes. It is suggested that the vasogenic cerebral edema was mainly caused by the augmentation of BBB permeability.