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The product rate variation problem minimizes the variation in the rate at which different models of a common base product are produced on the assembly lines with the assumption of negligible switch-over cost and unit processing time for each copy of each model. The assumption of significant setup and arbitrary processing times forces the problem to be a two phase problem. The first phase determines the size and the number of batches and the second one sequences the batches of models. In this paper, the bottleneck case i.e. the min-max case of the problem with a generalized objective function is formulated. A Pareto optimal solution is proposed and a relation between optimal sequences for the problem with different objective functions is investigated.

Research interests have been focused on the concept of penalizing jobs both for being early and for being tardy because not only of modern competitive industrial challenges of providing a variety of products at a very low cost by smoothing productions but also of its increasing and exciting computer applications. Here, sequencing approaches of the mixed- model just-in-time production systems is reviewed. In this note, realizing a need of critical review, a survey on the elegant mathematical models, methods and complexity of the mixed- model just-in-time sequencing problem with an insight into the existing analytical literature is given. The established research results together with open problems and possible extensions are presented.

The product rate variation problem minimizes the variation in the rate at which different models of a common base product are produced on the assembly lines with the assumption of negligible switch-over cost and unit processing time for each copy of each model. The assumption of significant setup and arbitrary processing times forces the problem to be a two phase problem. The first phase determines the size and the number of batches and the second one sequences the batches of models. In this paper, the bottleneck case i.e. the min-max case of the problem with a generalized objective function is formulated. A Pareto optimal solution is proposed and a relation between optimal sequences for the problem with different objective functions is investigated.

Research interests have been focused on the concept of penalizing jobs both for being early and for being tardy because not only of modern competitive industrial challenges of providing a variety of products at a very low cost by smoothing productions but also of its increasing and exciting computer applications. Here, sequencing approaches of the mixed- model just-in-time production systems is reviewed. In this note, realizing a need of critical review, a survey on the elegant mathematical models, methods and complexity of the mixed- model just-in-time sequencing problem with an insight into the existing analytical literature is given. The established research results together with open problems and possible extensions are presented.

An attempt was made to prove the phenomenon of myocardial collagen breakdown in a norepinephrine (NE) induced model of reversible cardiopathy in anesthetized rabbits. NE (0.3 mg/kg in 90 min) was infused to 22 animals. Histologically it was found that immediately and during the first two days after the catecholamine administration the myocardial collagenous network became disrupted and it partly disappeared. Collagenase and peptidase activities were measured from homogenates of the same hearts. A significant increase of these activities was observed and that could be correlated with the intracellular matrix destruction.

In 50 patients suffering for 1-15 years from rheumatoid arthritis, needle-biopsy of the synovial membrane was carried out. The finding correlated with the general clinical activity of the disease. Each type of histological change was evaluated with regard to its diagnostic value in assessing clinical activity. Among the histological changes, oedema, synovial cell proliferation, lymphocyte-plasma cell proliferation and necrotic vasculitis showed a negative correlation with clinical activity, while a positive correlation was observed between clinical activity and the presence of fibrin (fresh and old), fibrinoid, fibrinoid basophilia, fibroblast proliferation, synovial cell desquamation, concentric perivascular sclerosis, fibrosis and hyalinosis. Vascular changes of the synovial membrane such as oedema, fresh fibrin exudate, necrotic vasculitis showed a negative correlation with clinical activity while hyalinization and concentric sclerosis and clinical activity were found to be in positive correlation. It is concluded that in the course of rheumatoid arthritis the histological changes do not necessarily run parallel with the clinical activity of the disease.

The histological pattern of synovial needle-biopsies of 50 patients suffering from classical or definitive rheumatoid arthritis has been compared with the clinical activity of the disease. Each histological change was evaluated in terms of its value in characterizing local clinical activity. It was shown that most changes of the synovial ground tissue are in a positive correlation with local clinical activity. Among the vascular changes of the synovial membrane, oedema of vascular walls, exudation of fresh fibrin, leukocyte infiltration and thickening of vascular walls were in negative correlation, while chronic fibrin, lymphocytic or plasma cell infiltration and hyalinosis were in positive correlation with local clinical activity.

From complex biochemical, fluorescence-microscopic and enzyme-histochemical studies of the thyroid in rats it is concluded that the thyroid exerts, in addition to its catecholaminergic stimulatory effect, a serotonin-inhibiting regulatory activity, subject to the stimulatory effect of TRH.

The activity of rhodanese enzyme was studied histochemically in the cells of bone tissue of various ages and in various states of differentiation, and in chondroid and epiphyseal cartilage tissue. Enzyme activity was higher in the preexisting, differentiated laminar bone tissue of young animals than in that of old animals, and higher in newly formed woven bone than in the preexisting lamellar one and higher in chondroid tissue and in epiphyseal cartilage than in the woven bone and chondroid tissue. These differences are thought to reflect differences in metabolic intensity of the different structures.

Cytochrome oxidase activity was studied in articular and epiphyseal cartilage, in bone tissue and in callus. Changes in the activity of the enzyme were observed after ischaemic condition. Activity was the highest in the epiphyseal cartilage while in the other structures it decreased in the order of articular cartilage, chondroid tissue, newly formed woven bone, connective tissue cells, immature, preexisting lamellar bone tissue. It is assumed that differences in enzyme activity are due to differences in metabolic rate. The higher the activity of a structure in the intact state, the more marked was its decrease upon ischaemia. This implies that cells of higher metabolic rate are more sensitive to ischaemia.

The serum HCS concentration and urine estriol (E3) content was determined just before delivery in mature but intrauterine retarded and mature eutrophic cases. The hormonal parameters and the placental perfusion index (PPI) were determined in each case parallel. The mitochondrial glutamate dehydrogenase (GLDH) and the glycolytic lactate dehydrogenase (LDH) activity in the placentas were determined immediately after the placentas were born. Among the cases in which intrauterine retarded newborns were born the half of the women had gestosis during their pregnancy and the half had not any problem. It has been found that serum HCS concentration and urine E3 content were significantly lower in the pathologic groups compared to the control. The placental LDH activity significantly increased in both of the dysmature groups. The GLDH activity was normal in the toxemic cases but decreased significantly in the cases where the newborns were dysmature and the mother had no toxemia. There was a correlation between the serum HCS concentration and placental GLDH activity in non-toxemic cases. The perfusion was significantly lower in the toxemic cases only. At the same time there was no correlation between the placental perfusion and endocrine parameters or enzyme activities in both of the pathologic groups.

The oxidative enzyme system of the synovial membrane and rheumatoid node from rheumatoid arthritic patients has been studied by histochemical and biochemical methods. As compared to the control synovial membranes, succinic dehydrogenase activity was substantially higher in the rheumatoid arthritic synovial membranes, and was still higher in the rheumatoid nodes, in which only the cells forming the palisade had succinic dehydrogenase activity. As compared to the controls, in response to menadione succinic dehydrogenase was significantly activated. The reducible ubiquinone content of the rheumatoid synovial membrane and the rheumatoid node was by several orders of magnitude higher than in the controls.

The protracted effect of ultrasound treatment on the parenchymatous organs of rats has been studied histochemically at 1 to 10-day intervals. As a result of the altered redox conditions it is the oxidative enzymes in the first place that react to ultrasound treatment and their normalization takes a long time. Exposure decreased the activity of lysosomal enzymes and in the cell membrane the alkaline phosphatase and ATP-ase too. The activity of hydrolases returned to normal parallel with the normalization of the microscopic structure.

The PGE2 potentiated formalin arthritis can be only temporarily influenced by indomethacin. Azapropazone had a good therapeutic effect on chronic inflammation. According to the enzyme histochemical studies, azapropazone enhanced oxidative enzyme activity. This phenomenon may be interpreted as a sign of a favorable effect.