927 resultados para 091302 Automation and Control Engineering


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Thirty monoclonal antibodies from eight laboratories exchanged after the First Workshop on Monoclonal Antibodies to Human Melanoma held in March 1981 at NIH were tested in an antibody-binding radioimmunoassay using a panel of 28 different cell lines. This panel included 12 melanomas, three neuroblastomas, four gliomas, one retinoblastoma, four colon carcinomas, one lung carcinoma, one cervical carcinoma, one endometrial carcinoma, and one breast carcinoma. The reactivity pattern of the 30 monoclonal antibodies tested showed that none of them were directed against antigens strictly restricted to melanoma, but that several of them recognize antigenic structures preferentially expressed on melanoma cells. A large number of antibodies were found to crossreact with gliomas and neuroblastomas. Thus, they seem to recognize neuroectoderm associated differentiation antigens. Four monoclonal antibodies produced in our laboratory were further studied for the immunohistological localization of melanoma associated antigens on fresh tumor material. In a three-layer biotin-avidin-peroxidase system each antibody showed a different staining pattern with the tumor cells, suggesting that they were directed against different antigens.

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The multiscale finite-volume (MSFV) method is designed to reduce the computational cost of elliptic and parabolic problems with highly heterogeneous anisotropic coefficients. The reduction is achieved by splitting the original global problem into a set of local problems (with approximate local boundary conditions) coupled by a coarse global problem. It has been shown recently that the numerical errors in MSFV results can be reduced systematically with an iterative procedure that provides a conservative velocity field after any iteration step. The iterative MSFV (i-MSFV) method can be obtained with an improved (smoothed) multiscale solution to enhance the localization conditions, with a Krylov subspace method [e.g., the generalized-minimal-residual (GMRES) algorithm] preconditioned by the MSFV system, or with a combination of both. In a multiphase-flow system, a balance between accuracy and computational efficiency should be achieved by finding a minimum number of i-MSFV iterations (on pressure), which is necessary to achieve the desired accuracy in the saturation solution. In this work, we extend the i-MSFV method to sequential implicit simulation of time-dependent problems. To control the error of the coupled saturation/pressure system, we analyze the transport error caused by an approximate velocity field. We then propose an error-control strategy on the basis of the residual of the pressure equation. At the beginning of simulation, the pressure solution is iterated until a specified accuracy is achieved. To minimize the number of iterations in a multiphase-flow problem, the solution at the previous timestep is used to improve the localization assumption at the current timestep. Additional iterations are used only when the residual becomes larger than a specified threshold value. Numerical results show that only a few iterations on average are necessary to improve the MSFV results significantly, even for very challenging problems. Therefore, the proposed adaptive strategy yields efficient and accurate simulation of multiphase flow in heterogeneous porous media.

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Selostus: Ilmaston lämpenemisen vaikutus perunaruttoon

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OBJECTIVE: Evaluation of the quantitative antibiogram as an epidemiological tool for the prospective typing of methicillin-resistant Staphylococcus aureus (MRSA), and comparison with ribotyping. METHODS: The method is based on the multivariate analysis of inhibition zone diameters of antibiotics in disk diffusion tests. Five antibiotics were used (erythromycin, clindamycin, cotrimoxazole, gentamicin, and ciprofloxacin). Ribotyping was performed using seven restriction enzymes (EcoRV, HindIII, KpnI, PstI, EcoRI, SfuI, and BamHI). SETTING: 1,000-bed tertiary university medical center. RESULTS: During a 1-year period, 31 patients were found to be infected or colonized with MRSA. Cluster analysis of antibiogram data showed nine distinct antibiotypes. Four antibiotypes were isolated from multiple patients (2, 4, 7, and 13, respectively). Five additional antibiotypes were isolated from the remaining five patients. When analyzed with respect to the epidemiological data, the method was found to be equivalent to ribotyping. Among 206 staff members who were screened, six were carriers of MRSA. Both typing methods identified concordant of MRSA types in staff members and in the patients under their care. CONCLUSIONS: The quantitative antibiogram was found to be equivalent to ribotyping as an epidemiological tool for typing of MRSA in our setting. Thus, this simple, rapid, and readily available method appears to be suitable for the prospective surveillance and control of MRSA for hospitals that do not have molecular typing facilities and in which MRSA isolates are not uniformly resistant or susceptible to the antibiotics tested.

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By simulations of the Barkley model, action of uniform periodic nonresonant forcing on scroll rings and wave turbulence in three-dimensional excitable media is investigated. Sufficiently strong rapid forcing converts expanding scroll rings into the collapsing ones and suppresses the Winfree turbulence caused by the negative tension of wave filaments. Slow strong forcing has an opposite effect, leading to expansion of scroll rings and induction of the turbulence. These effects are explained in the framework of the phenomenological kinematic theory of scroll waves.

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Multiplan spreadsheet solutions were developed for a set of hydraulic and highway engineering computations of common interest to county engineers. These include earthwork, vertical and horizontal curves, staking superelevated curves and sign inventories for highways. The hydraulic applications were ditch flow, runoff, culvert size and stage discharge.

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Twenty-four-hour energy expenditure (24-EE), resting metabolic rate (RMR) and body composition were determined in 30 subjects from three groups; control (103 +/- 2% ideal body weight, n = 10), moderately obese (129 +/- 1% ideal body weight, n = 6), and obese (170 +/- 5% ideal body weight, n = 14) individuals. Twenty-four EE was measured in a comfortable airtight respiration chamber. When expressed as absolute values, both RMR and 24-EE were significantly increased in obese subjects when compared to normal weight subjects. The RMR was 7592 +/- 351 kJ/day in the obese, 6652 +/- 242 kJ/day in the moderately obese, and 6118 +/- 405 kJ/day in the controls. Mean 24-EE values were 10043 +/- 363, 9599 +/- 277, and 8439 +/- 432 kJ/day in the obese, moderately obese, and controls, respectively. The larger energy expenditure in the obese over 24 h was mainly due to a greater VO2 during the daylight hours. However, 92% of the larger 24-EE in the obese, compared to the control group, was accounted for by the higher RMR and only 8% by other factors such as the increased cost of moving the extra weight of the obese. The higher RMR and 24-EE in the obese was best related to the increased fat free mass.

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BACKGROUND: The evidence for a "diabesity" epidemic is accumulating worldwide but population-based data are still scarce in the African region. We assessed the prevalence, awareness and control of diabetes (DM) in the Seychelles, a rapidly developing country in the African region. We also examined the relationship between body mass index, fasting serum insulin and DM. METHODS: Examination survey in a sample representative of the entire population aged 25-64 of the Seychelles, attended by 1255 persons (participation rate of 80.2%). An oral glucose tolerance test (OGTT) was performed in individuals with fasting blood glucose between 5.6 and 6.9 mmol/l. Diabetes mellitus (DM), impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) were defined along criteria of the ADA. Prevalence estimates were standardized for age. RESULTS: The prevalence of DM was 11.5% and 54% of persons with DM were aware of having DM. Less than a quarter of all diabetic persons under treatment were well controlled for glycemia (HbA1c), blood pressure or LDL-cholesterol. The prevalence of IGT and IFG were respectively 10.4% and 24.2%. The prevalence of excess weight (BMI > or = 25 kg/m2) and obesity (BMI > or = 30 kg/m2) was respectively 60.1% and 25.0%. Half of all DM cases in the population could be attributed to excess weight. CONCLUSION: We found a high prevalence of DM and pre-diabetes in a rapidly developing country in the African region. The strong association between overweight and DM emphasizes the importance of weight control measures to reduce the incidence of DM in the population. High rates of diabetic persons not aware of having DM in the population and insufficient cardiometabolic control among persons treated for DM stress the need for intensifying health care for diabetes.

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The prevalence of keratosis pilaris and accentuated palmoplantar marking was evaluated in 61 patients with atopic dermatitis, 35 patients with dominant ichthyosis vulgaris and 247 other dermatological cases taken as controls. Our data showed that (1) these features are of no diagnostic significance for atopic dermatitis and (2) they are significantly more frequent in patients with ichthyosis vulgaris without associated eczema than in those with atopic dermatitis. Consequently, they should be considered as part of the phenotype of ichthyosis vulgaris rather than attributed to a concomitant atopic dermatitis as suggested by some. These findings should be taken into account when evaluating atopic dermatitis or ichthyosis. To assess the frequency of scaling under winter weather conditions, 155 control subjects were also examined for evidence of visible desquamation and 25.8% showed slight but definite scaling.

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The material presented in the these notes covers the sessions Modelling of electromechanical systems, Passive control theory I and Passive control theory II of the II EURON/GEOPLEX Summer School on Modelling and Control of Complex Dynamical Systems.We start with a general description of what an electromechanical system is from a network modelling point of view. Next, a general formulation in terms of PHDS is introduced, and some of the previous electromechanical systems are rewritten in this formalism. Power converters, which are variable structure systems (VSS), can also be given a PHDS form.We conclude the modelling part of these lectures with a rather complex example, showing the interconnection of subsystems from several domains, namely an arrangement to temporally store the surplus energy in a section of a metropolitan transportation system based on dc motor vehicles, using either arrays of supercapacitors or an electric poweredflywheel. The second part of the lectures addresses control of PHD systems. We first present the idea of control as power connection of a plant and a controller. Next we discuss how to circumvent this obstacle and present the basic ideas of Interconnection and Damping Assignment (IDA) passivity-based control of PHD systems.

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We show that transport in the presence of entropic barriers exhibits peculiar characteristics which makes it distinctly different from that occurring through energy barriers. The constrained dynamics yields a scaling regime for the particle current and the diffusion coefficient in terms of the ratio between the work done to the particles and available thermal energy. This interesting property, genuine to the entropic nature of the barriers, can be utilized to effectively control transport through quasi-one-dimensional structures in which irregularities or tortuosity of the boundaries cause entropic effects. The accuracy of the kinetic description has been corroborated by simulations. Applications to different dynamic situations involving entropic barriers are outlined.

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Although glucose is the major regulator of insulin secretion by pancreatic beta cells, its action is modulated by several neural and hormonal stimuli. In particular, hormones secreted by intestinal endocrine cells stimulate glucose-induced insulin secretion very potently after nutrient absorption. These hormones, called gluco-incretins or insulinotropic hormones, are major regulators of postprandial glucose homeostasis. The main gluco-incretins are GIP (gastric inhibitory polypeptide or glucose-dependent insulinotropic polypeptide) and GLP-1 (glucagon-like polypeptide-1). The secretion of GIP, a 42 amino acid polypeptide secreted by duodenal K cells, is triggered by fat and glucose. GIP stimulation of insulin secretion depends on the presence of specific beta-cell receptors and requires glucose at a concentration at least equal to or higher than the normoglycaemic level of approximately 5 mM. GIP accounts for about 50% of incretin activity, and the rest may be due to GLP-1 which is produced by proteolytic processing of the preproglucagon molecule in intestinal L cells. GLP-1 is the most potent gluco-incretin characterized so far. As with GIP, its stimulatory action requires a specific membrane receptor and normal or elevated glucose concentrations. Contrary to GIP, the incretin effect of GLP-1 is maintained in non-insulin-dependent diabetic patients. This peptide or agonists of its beta-cell receptor could provide new therapeutic tools for the treatment of Type II diabetic hyperglycaemia.

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The Division of Tobacco Use Prevention and Control works to reduce tobacco use and the toll of tobacco-caused disease and death by preventing youth from starting, helping Iowans to quit, and preventing exposure to secondhand smoke. Tobacco is the leading preventable cause of death for Iowans, taking the lives of more than 4,400 adults each year. Estimated annual health care costs in Iowa directly related to tobacco use now total $1 billion.

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The objective of this work was to evaluate the effects of plant essential oils (EOs) on the growth of Xanthomonas vesicatoria, on bacterial morphology and ultrastructure, and on the severity of tomato bacterial spot. EOs from citronella, clove, cinnamon, lemongrass, eucalyptus, thyme, and tea tree were evaluated in vitro at concentrations of 0.1, 1.0, 10, and 100% in 1.0% powdered milk. The effect of EOs, at 0.1%, on the severity of tomato bacterial spot was evaluated in tomato seedlings under greenhouse conditions. The effects of citronella, lemongrass, clove, and tea tree EOs, at 0.1%, on X. vesicatoria cells were evaluated by transmission electron microscopy. All EOs showed direct toxic effect on the bacteria at a 10%-concentration in vitro. Under greenhouse conditions, the EOs of clove, citronella, tea tree, and lemongrass reduced disease severity. EOs of clove and tea tree, and streptomycin sulfate promoted loss of electron-dense material and alterations in the cytoplasm, whereas EO of tea tree promoted cytoplasm vacuolation, and those of citronella, lemongrass, clove, and tea tree caused damage to the bacterial cell wall. The EOs at a concentration of 0.1% reduce the severity of the disease.

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Tutkielman tavoitteena on määritellä projektikontrolloinnin ja - riskijohtamisen roolit ja toiminnot saksalaisissa kone- ja tehdassuunnitteluteollisuusyrityksissä. Tämä on kvalitatiivinen tutkielma, jossa käytetään voimakkaasti kuvailevia metodeita. Materiaali tutkimuksen empiiriseen osaan kerättiin kyselykaavakkeen avulla. Kyselykaavakkeiden tulokset käsiteltiin Microsoft Office Access- ohjelmalla ja analysoitiin Microsoft Office Excel- ohjelmalla ja Pivot table- työkalun avulla. Tutkimustulokset osoittavat, että asianmukaisessa projektikontrollointi- ja riskijohtamismetodien käytössä ja käyttötiheydessä esiintyy puutteita saksalaisissa kone- ja tehdassuunnitteluteollisuusyrityksissä. Tehostamalla ja keskittymällä enemmän projektikontrollointi- ja riskijohtamismetodeihin ja prosesseihin sekä projektien että yritysten suorituskyky paranisi.