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Drift parking represents an extreme maneuver that is beyond the skill set of the average driver, requiring adept use and timing of the handbrake, pedal brake, and steering wheel. The maneuver causes the vehicle to rotate rapidly and slide, nearly sideways (i.e. high side slip angle), into the desired parking spot. In this paper we propose a control strategy to quickly park a vehicle in a narrow space using a high side slip angle maneuver, or ‘drift parking’ maneuver. The proposed control scheme switches between nonlinear model predictive control and a linear feedforward-feedback policy. For experimental validation, we use an open source, low cost 1/10 scale RC vehicle called the Berkeley Autonomous Race Car developed at UC Berkeley.

Expert drivers have the skill to perform high side slip maneuvers, like drifting, during racing events to minimize lap time. Due to the complex dynamics of these maneuvers, transient drift is difficult to model and to control in autonomous vehicles.

The paper presents the design of a lateral stability controller for ground vehicles based on front steering and four wheels independent braking. The control objective is to track yaw rate and lateral velocity reference signals while avoiding front and rear wheel traction force saturation. Control design is based on an approximate piecewise–affine nonlinear dynamical model of the vehicle. Vehicle longitudinal velocity and drivers steering input are modeled as measured disturbances taking values in a compact set. A time–optimal control strategy which ensures convergence into a maximal robust control invariant (RCI) set is proposed. This paper presents the uncertain model, the RCI computation, and the control algorithm. Simulations results on a high–fidelity vehicle model show the effectiveness of the propose scheme.

Background & Aims: Cholera toxin (CT) is the most recognizable enterotoxin causing secretory diarrhea, a major cause of infant morbidity and mortality throughout the world. In this study, we investigated the role of the endogenous cannabinoid system (i.e., the cannabinoid receptors and their endogenous ligands) in CT-induced fluid accumulation in the mouse small intestine. Methods: Fluid accumulation was evaluated by enteropooling; endocannabinoid levels were measured by isotope-dilution gas chromatography mass spectrometry; CB"1 receptors were localized by immunohistochemistry and their messenger RNA (mRNA) levels were quantified by reverse-transcription polymerase chain reaction (PCR). Results: Oral administration of CT to mice resulted in an increase in fluid accumulation in the small intestine and in increased levels of the endogenous cannabinoid, anandamide, and increased expression of the cannabinoid CB"1 receptor mRNA. The cannabinoid receptor agonist CP55,940 and the selective cannabinoid CB"1 receptor agonist arachidonoyl-chloro-ethanolamide inhibited CT-induced fluid accumulation, and this effect was counteracted by the CB"1 receptor antagonist SR141716A, but not by the CB"2 receptor antagonist SR144528. SR141716A, per se, but not the vanilloid VR1 receptor antagonist capsazepine, enhanced fluid accumulation induced by CT, whereas the selective inhibitor of anandamide cellular uptake, VDM11, prevented CT-induced fluid accumulation. Conclusions: These results indicate that CT, along with enhanced intestinal secretion, causes overstimulation of endocannabinoid signaling with an antisecretory role in the small intestine.

It has been established that follicle stimulating hormone (FSH) circulates in the bloodstream as a heterogeneous population of molecules. Individual FSH isoforms, while displaying identical amino acid sequences, differ in their extent of post-translational modification. As a result of these variations, the FSH isoforms exhibit differences in overall charge, degree of sialic acid or sulphate incorporation, receptor binding affinity and plasma half-life. Taking advantage of the fact that these forms can be separated from each other on the basis of their charge, we have evaluated in rats the metabolic clearance rates of the acidic [with an isoelectric point (pI) ≤ISOdia≤ 4.8] and the less acidic (pI > 4.8) isoforms of recombinant human FSH (rhFSH) obtained after chromatofocusing. The less acidic isoform group was found to have a faster clearance from the circulation in rats as compared with the acidic isoform group. This finding is in agreement with the lower bioactivity in vivo (as determined by the Steelman–Pohley assay) of the less acidic isoform group, compared with the acidic one. The mass spectra of the two groups of isoforms showed a difference in the sialic acid content thus highlighting the importance of these residues on the in-vivo activity of FSH. Conversely, when the two groups of isoforms were tested in vitro by using the Y1 human FSH receptor (Y1 hFSHR) assay and a reporter gene assay, no significant differences in the biological activities between these preparations were detected when test concentrations were based on mass.

It has been established that follicle stimulating hormone (FSH) circulates in the bloodstream as a heterogeneous population of molecules. Individual FSH isoforms, while displaying identical amino acid sequences, differ in their extent of post-translational modification. As a result of these variations, the FSH isoforms exhibit differences in overall charge, degree of sialic acid or sulphate incorporation, receptor binding affinity and plasma half-life. Taking advantage of the fact that these forms can be separated from each other on the basis of their charge, we have evaluated in rats the metabolic clearance rates of the acidic [with an isoelectric point (pI) 4.8) isoforms of recombinant human FSH (rhFSH) obtained after chromatofocusing. The less acidic isoform group was found to have a faster clearance from the circulation in rats as compared with the acidic isoform group. This finding is in agreement with the lower bioactivity in vivo (as determined by the Steelman-Pohley assay) of the less acidic isoform group, compared with the acidic one. The mass spectra of the two groups of isoforms showed a difference in the sialic acid content thus highlighting the importance of these residues on the in-vivo activity of FSH. Conversely, when the two groups of isoforms were tested in vitro by using the Y1 human FSH receptor (Y1 hFSHR) assay and a reporter gene assay, no significant differences in the biological activities between these preparations were detected when test concentrations were based on mass.

The effect of phosvitin (1 g kg−1, i.p.) on ecg changes induced in rats by a reduction of partial oxygen pressure in the respiratory mixture was studied. Phosphocreatine, phosphoserine, ATP and Na2HPO4.2H2O were also administered intraperitoneally for comparison. Phosvitin alone was found to prevent the hypoxia-induced T-wave changes (flattening or disappearance), which were also temporarily aggravated by injection of noradrenaline. As to the metabolic, hypoxia-induced myocardial changes, two hypotheses are discussed: a release of phosvitin phosphate radicals ready for immediate utilization or a drug action mediated via a membrane-bound intrinsic proteinkinase system.

Local reactions have been frequently reported following repeated injections of human menopausal gonadotrophins (HMG) for the treatment of infertility. Also immunoglobulin (Ig) E-mediated systemic reactions have sporadically been observed. Since most HMG preparations contain significant amounts of non-hormonal urine-derived proteins, it was suggested that these contaminating proteins are responsible for the various allergic reactions. In order to verify this hypothesis, different human follicle stimulating hormone (HFSH) and HMG preparations (Metrodin and Pergonal from Ares-Serono, and Humegon from Organon), were compared with a highly purified preparation (Metrodin HP from Ares-Serono) for the frequency and severity of allergic reactions induced in laboratory animals. The occurrence of anaphylactic shock or related symptoms was studied in sensitized guinea-pigs. The production of specific IgE was evaluated in serum from mice sensitized with the test drugs by the induction of passive cutaneous anaphylaxis in rats. In both models, two different schedules of sensitization were used. Severe allergic reactions were found in 20 of 7% of the guinea-pigs receiving highly purified FSH (Metrodin HP) in the two schedules, respectively, compared to 90 and 88% with the other preparations. Similarly significantly lower IgE titres were induced by highly purified FSH in respect to the other preparations. It can be concluded that the elimination of contaminating proteins significantly reduces the allergenicity of urine-derived HFSH preparations.

Aloe is one of the few medicinal plants that has maintained its popularity for a long period of time. Aloe latex is used for its laxative effect and should be distinguished from aloe gel, used both in cosmetics and ointments for skin ailments. Aloe whole leaf is another preparation used internally as a drink in a wide range of human diseases including cancer, AIDS, ulcerative colitis and other disturbances. The concomitant use of honey may make the aloe whole leaf therapy more palatable and efficient. © 1998 John Wiley & Sons, Ltd.

Castor oil (2 ml/rat) produced copious diarrhoea in all rats 3 h after challenge, which was associated with histologic damage to the duodenal and jejunal mucosa. Pretreatment of animals with the nitric oxide (NO) synthesis inhibitor N G -nitro-L-arginine methyl ester (L-NAME, 50 mg/kg, i.p.) reverted the diarrhoea, but, exacerbated histological damage. The NO donating compound isosorbide-5-mononitrate (IMN, 150 mg/kg p.o.) counteracted the augmentation by L-NAME of the castor oil-induced diarrhoea and histological damage. The independence of the diarrhoeal and damaging effects of castor oil suggest that NO (i) has protective effects on the rat intestinal mucosa, (ii) mediates laxation and (iii) modulates the release of local cytotoxic substances.

The effect of ditazole, a new antiaggregant oxazole derivative as well as its possible interaction with urokinase on the formation of electrically induced thrombus, was assayed in rabbits. The activity of ditazole in reducing thrombus weight was comparable to that of aspirin. In the ditazole- or aspirin-treated animals, the microscopical examination of the thrombus showed a reduction in the fibrin component, and well-isolated platelets not undergoing a viscous metamorphosis were present. Urokinase, administered in combination with these antiaggregant drugs, did not induce a further reduction in thrombus weight. However, this additional treatment did induce clearly visible lytic areas and histological modifications as observed with the antiaggregant drugs. These data suggest that the antiplatelet drug ditazole may be an effective antithrombotic agent in man and could facilitate the penetration of urokinase into the thrombus.

Digitalis and other plants containing cardioactive glycosides are infrequently used today for congestive heart failure. Hawthorn has positive inotropic effects and accelerates the heart rate but its use is restricted to the prevention of angina. Ginkgo is employed in chronic cerebral ischaemia and intermittent claudication while horse‐chestnut is effective in chronic venous insufficiency. These vegetable drugs are useful in themselves and also in association with more effective therapeutic agents. © 1998 John Wiley & Sons, Ltd.

Local reactions have been frequently reported following repeated injections of human menopausal gonadotrophins (HMG) for the treatment of infertility. Also immunoglobulin (Ig) E-mediated systemic reactions have sporadically been observed. Since most HMG preparations contain significant amounts of non-hormonal urine-derived proteins, it was suggested that these contaminating proteins are responsible for the various allergic reactions. In order to verify this hypothesis, different human follicle stimulating hormone (HFSH) and HMG preparations (Metrodin and Pergonal from Ares-Serono, and Humegon from Organon), were compared with a highly purified preparation (Metrodin HP from Ares-Serono) for the frequency and severity of allergic reactions induced in laboratory animals. The occurrence of anaphylactic shock or related symptoms was studied in sensitized guinea-pigs. The production of specific IgE was evaluated in serum from mice sensitized with the test drugs by the induction of passive cutaneous anaphylaxis in rats. In both models, two different schedules of sensitization were used. Severe allergic reactions were found in 20 and 7% of the guinea-pigs receiving highly purified FSH (Metrodin HP) in the two schedules, respectively, compared to 90 and 88% with the other preparations. Similarly significantly lower IgE titres were induced by highly purified FSH in respect to the other preparations. It can be concluded that the elimination of contaminating proteins significantly reduces the allergenicity of urine-derived HFSH preparations.