Multiobjective problems: Linear and nonlinear control

In this note, we compare the value of nonlinear and linear control for a multiobjective control problem with a linear time-invariant (LTI) plant. We show that if the performance of a nonlinear feedback controller is measured by the maximum incremental gain, the optimal achievable performance with nonlinear, time-varying control is identical to that achievable by LTI control.     

Relative value of peripheral blood, secretion and tissue eosinophilia in the diagnosis of different patterns of allergic rhinitis

Eosinophil count in peripheral blood, nasal secretion and nasal mucosa were studied in 20 controls and 38 patients with different patterns of allergic rhinits. Secretion and tissue eosinophilia were pathologically high in a greater number of patients than peripheral blood eosinophilia. This trend was seen in all patterns of allergic rhinitis but was more evident in seasonal allergic rhinitis. The conclusion was reached that examination of local site and local secretions for eosinophilia is helpful in the diagnosis and differential diagnosis of allergic rhinitis.     

Differential diagnosis of allergic diseases of the upper respiratory tract

The author studied various manifestations of the most widely spread clinical forms of allergic diseases of the upper respiratory tract, namely, the bacterial, atopic and combined ones. In addition to clinical investigations laborotory, immunologic and functional tests were conducted. The difference in pathogenesis affected the clinical course of the disease. Some symptoms depended on the kind of sensibilization, others on how strongly pronounced the pathologic process was.     

Space flight effects on skeletal bones of rats (light and electron microscopic examination)

In the light and electron microscopes, long tubular bones of Wistar rats that were flown for 22 d onboard the Cosmos-605 biosatellite and were exposed to a ground-based simulation experiment were examined. About half of the flight rats showed osteoporosis of metaphyses which was usually combined with a decrease of the mass of the primary spongiosa in the vicinity of the epiphyseal cartilaginous plate. This gives evidence that the growth of the bones could have been inhibited in flight. The light and electron microscopy of bones of flight rats revealed wide osteocyte lacunae which could have been produced by perilacunar osteolysis. In the simulation experiment, reduction in the metaphyseal spongiosa occurred only in one-third of the rats and was less pronounced than in flight rats; no decrease of the mass of the primary spongiosa near the cartilaginous plate was noted. Histological investigation of bones 27 d postflight demonstrated that that time period was not enough to eliminate all the changes in the bones tested.     

A study of the protein composition of the zona pellucida of mammalian oocytes and zygotes by a method of microelectrophoresis in polyacrylamide gel

It is known that drugs are not unlimitedly stable. Dilutions of the antineoplastic agent daunoblastin used in the clinic and experimental work, were examined, whether they could be stored for several days. By means of impulscytophotometry, spectral-photometric measurements, counting of surviving cells and estimation of DNA-synthesis after culturing pieces of tissue in the presence of daunoblastin it could be established that this drug, diluted even four days ago, still possesses sufficient activity.     

Catalytic ozonation of propanal using wood fly ash and metal oxide nanoparticle impregnated carbon

Catalytic ozonation of propanal at ambient temperatures (23-25 degrees C) was investigated by varying propanal and ozone concentrations and catalyst type. The catalysts tested included wood fly ash (WFA), magnetically separated ash, synthetic hematite and magnetite, and metal oxide nanoparticle impregnated activated carbon and peanut hull char. A power law model independent of ozone concentration for WFA (r(w), moles g(-1) s(-1)) and magnetite (r(m)) were, respectively, r(w) = k'(w) C(R(0.89)) and r(m) = k'(m)C(R(1.55)), where kw, and k'(m) were 2.36 x 10(-6) g(-1) s(-1) (moles)(-0.11) (m3)(0.89) and 6.5 x 10(-4) g(-1) s(-1) (moles)(-0.55) (m3)(1.55), respectively (5-15 ppmv). Magnetite and hematite present in the WFA were theorized to be the primary active sites, since magnetically separated WFA had a significantly higher reaction rate (approximately 12x, mol m(-2) s(-1)) than that of WFA. X-ray diffraction analysis demonstrated a qualitative increase in magnetite and hematite in the magnetically separated ash, and synthetic magnetite and hematite had reaction rates >80x and 200x that of WFA or activated carbon (surface area basis). Supercritical deposition of hematite on/in peanut hull char successfully generated a porous, pelleted catalystfrom an agricultural residue capable of oxidizing propanal at rates 12x activated carbon and similar to commercially available catalysts (per mass basis). Water vapor significantly increased the propanal reaction rate when using wood fly ash and activated carbon.