Properties of a combined adaptive/second-order sliding mode controlalgorithm for some classes of uncertain nonlinear systems

In this paper, a combined adaptive/variable structure control approach is presented that exploits the good properties of the backstepping procedure and of a second-order sliding-mode control algorithm. This algorithm enables one to attain the conditions S=0, S˙=0 (second-order sliding mode) in a finite time, S=0 being a predefined sliding manifold. The combined approach retains the stability and convergence features of the original adaptive strategy. In addition, it allows one to deal with systems with uncertainties of more general types, ensuring robustness, as well as a reduction in the computational load     

Molecular biology in the modern work-up of the infertile male: the time to recognize the need for andrologists

The purpose of this study was to explore dangerousness and fire setting recidivism of mentally disordered firesetters in comparison with mentally healthy arsonists. In Germany, all trials are registered centrally by the Federal Central Register. The records of this Register for the three year period from 1983 until 1985 were used in this follow-up study of arsonists to identify three samples of subjects: (1) All persons convicted of arson who have been found not guilty by reasons of insanity (n = 186), (2) all person convicted of arson who have been found guilty of diminished responsibility (n = 97), and (3) a random selection from all persons convicted of arson who have had no psychiatric examination in their trial (n = 187). The follow-up ended in 1994, providing a period of, on average, ten years. Mentally disordered arsonists differed from non-mentally disordered arsonists in the following ways: They were more likely, first, to have a history of arson before 1983, and secondly, to be convicted of arson again (11% relapse compared to 4%). Mentally disordered arsonists had fewer registrations of common offenses, such as theft as well as traffic violations and alcohol-related offenses. Based on the present sample, mentally disordered firesetters have a higher rate of recurrence of firesetting than non-mentally disordered firesetters and commit fewer common offenses other than firesetting.     

Nucleoside transport in isolated human and rhesus choroid plexus tissue slices

Paget's disease is a common entity but osteosarcoma arising in Paget's disease is an infrequent complication. Primary osteosarcomas are typically long bone tumours and the skull is rarely affected. A case with malignant transformation of Paget's disease of the skull and an unusual clinical presentation is reported. Computed tomography scans of the tumour area show interesting results. Main features are: an intensive sclerotic reaction of the host bone, an inner and outer spiculation of the calvarium, radial ossifications in the soft extracranial mass, and spotty calcifications and ossifications of the osteosarcomatous portion infiltrating the brain.     

Self-tuning control of robot manipulators

We consider the tracking control problem for robot manipulators whose parameters are not exactly known. It is assumed that some unmodelled friction is acting at the actuated joints. The proposed solution guarantees that the disturbances on the outputs (the joint positions) can be attenuated by an arbitrary factor k. For the setpoint regulation problem a self-tuning controller is proposed. In this case the disturbances (uncertain parameters and unmodelled non-linearities) on the outputs are completely rejected asymptotically. Some simulation results are included.     

A qualitative approach to cell growth modeling and simulation forcancer chemotherapy

A qualitative model of cell growth that is based on qualitative process theory is presented. The model can be used to analyze the effects of the interaction of antiproliferative drugs on cells when the effects of each specific drug are known, which is useful when designing multidrug protocols for optimal cancer treatment. This model encompasses both structural and behavioral aspects. This makes it suitable for drawing conclusions about differences among different types of cell growth and about system behavior under different situations. adding some significant options with respect to closed-form cell cycle models. Moreover, qualitative modeling, unlike closed-form modeling, allows causal explanations of events: in this respect, the qualitative simulation presented-based on reasoning in terms of processes, individual views. and history limits-makes causes of specific behaviors even clearer than qualitative simulation based on constraints. This model is able to adapt to the amount of information supplied by the user: if this is scarce (only relating to the cell cycle phase on which each drug acts), the model will produce a simulation in which only cell cycle phase information for the combination is present; if the information supplied is more detailed, the simulation output will be more detailed as well     

A way to decylamine-stabilized gold nanoparticles of tailored sizes tuning their growth in solution

Acetone solvated Au nanoparticles (Au NPs) were prepared by Metal Vapour Synthesis (MVS) co-condensing Au and acetone vapours. Nanoparticles growth was quenched at different times by using decylamine (DA) as stabilizer and DA-stabilized Au NPs were characterized by UV-Vis, NMR DOSY and HRTEM techniques. The dependence of metal clustering processes on gold concentration was investigated.     

Optimal therapy scheduling for a simplified HIV infection model

This work is motivated by the drug therapy scheduling problem in HIV infection. Using simplified switched linear system models of HIV mutation and treatment with certain class of symmetry and finite horizon cost functions, we demonstrate that the optimal state and costate trajectories lie on a sliding surface where infinitely fast switching may occur. Results suggest that in the absence of other practical constraints, switching rapidly between therapies is relevant. Simulations show the potential benefits of a proactive switching strategy to minimize viral load and delay the emergence of resistant mutant viruses.     

Control of mechanical systems with flexibility via a multi-input VS/backstepping design

The use of a multi-input control design procedure to determine the control law for a class of mechanical systems with uncertainties and flexibilities is described. The proposed procedure is based on the well-known backstepping design technique and relies on the possibility of extending a recently developed second-order sliding mode control approach to multi-input systems with non-matched uncertainties. This keeps the computational load reasonable and increases robustness.     

Folic Acid Functionalized Surface Highlights 5‐Methylcytosine‐Genomic Content within Circulating Tumor Cells

Although the detection of methylated cell free DNA represents one of the most promising approaches for relapse risk assessment in cancer patients, the low concentration of cell‐free circulating DNA constitutes the biggest obstacle in the development of DNA methylation‐based biomarkers from blood. This paper describes a method for the measurement of genomic methylation content directly on circulating tumor cells (CTC), which could be used to deceive the aforementioned problem. Since CTC are disease related blood‐based biomarkers, they result essential to monitor tumor's stadiation, therapy, and early relapsing lesions. Within surface's bio‐functionalization and cell's isolation procedure standardization, the presented approach reveals a singular ability to detect high 5‐methylcytosine CTC‐subset content in the whole CTC compound, by choosing folic acid (FA) as transducer molecule. Sensitivity and specificity, calculated for FA functionalized surface (FA‐surface), result respectively on about 83% and 60%. FA‐surface, allowing the detection and characterization of early metastatic dissemination, provides a unique advance in the comprehension of tumors progression and dissemination confirming the presence of CTC and its association with high risk of relapse. This functionalized surface identifying and quantifying high 5‐methylcytosine CTC‐subset content into the patient's blood lead significant progress in cancer risk assessment, also providing a novel therapeutic strategy.