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31.
Gerardo Gabriel Acosta Miguel Angel Mayosky José Maria Catalfo 《Applied Intelligence》1994,4(1):53-66
This article proposes a scheme for the on-line adjustment of three mode controller settings based on experimental measurements of closed-loop performance. It uses a recently developed heuristic tuning procedure to identify estimated process parameters. This method may give rise to conflicting estimates. Fuzzy Set theory is applied to manage the situation in terms of a fuzzy conjunction to combine the various estimates. PID control was chosen because of its wide use in the industrial environment due to driving simplicity and robustness. The article shows design, development, and computer simulation aspects. 相似文献
32.
The present study investigated the influence of dietary protein on the intensity of parasitaemia, degree of anaemia and erythropoietic responses, in sheep experimentally infected with Trypanosoma congolense and given either a high protein diet (116 g digestible crude protein [DCP] per day) or a low protein diet (51.5 g DCP per day). It was observed that infected and control animals on the high protein diet grew at similar rates while infected animals on the low protein diet experienced marked retardation of growth compared with their uninfected controls. Dietary protein had no influence on the degree of anaemia that followed infection. Measurement of blood volumes revealed that low protein infected group had significantly lower mean circulating red cell volume than their controls. Ferrokinetic measurements indicated that plasma iron turnover rates (PITR) and 59Fe incorporation rates were higher in the high protein infected group than in the low protein infected group, although these differences were not significant. These observations indicate that infected animals on a high protein tended to show greater enhancement of erythropoietic activity that infected animals on low protein diet. 相似文献
33.
Jarrett Robin B.; Basco Monica R.; Risser Richard; Ramanan Janaki; Marwill Maria; Kraft Dolores; Rush A. John 《Canadian Metallurgical Quarterly》1998,66(6):1036
Two pilot studies evaluated the rate of relapse or recurrence (i.e., major depressive disorder) after cognitive therapy (CT). Two sequential cohorts included outpatients who responded to acute phase CT (A-CT) and who agreed to monthly, treatment-free follow-up. In Study 1, the Kaplan-Meier technique estimated relapse and recurrence rates of 40% at 6 months, 45% at 8 months, 50% at 12 months, 67% at 18 months, and 74% at 24 months. In Study 2, responders to A-CT received 8 months (10 sessions) of continuation phase CT (C-CT). In Study 2, relapse or recurrence was 20% at 6 and 8 months, 27% at 12 months, and 36% at 18 and 24 months after A-CT. An exploratory log-rank test showed that relapse or recurrence-free survival was greater in Study 2 than in Study 1. If replicated, this result suggests that C-CT can reduce depressive relapse or recurrence. Alternative explanations are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
The aim this study was to report findings on the concentrations of mean triiodothyroxine (T3), thyroxin (T4), thyroid stimulating hormone (TSH) and prolactin (Prl) in patients with benign mastopathy and in control group. All of the examined subjects were clinically euthyroid. The mean T4 concentrations in women with mastopathy (78.25 +/- 15.27 ng/ml) were significantly lower than in control group 88.73 +/- 15.27). The mean TSH and PRL concentration in women with mastopathy were higher, but not significantly, than in control women. This results indicate, that benign mastopathy seems to be connected with thyroid functions. 相似文献
35.
Maria G Corradini Mark D Normand Micha Peleg 《Journal of the science of food and agriculture》2006,86(5):785-792
Currently, the sterility of heat‐processed food and pharmaceuticals is assessed in terms of an F0 value, based on the equivalence of the heat treatment to an isothermal process at a reference temperature. This F0 value, however, has a meaning if, and only if, the inactivation kinetics of the targeted spores (or cells) follow a first‐order relationship and the temperature dependence of the D value, the reciprocal of the rate constant, is log‐linear. There is growing evidence that these conditions are not satisfied by many spores, including those of Clostridium botulinum and vegetative cells. Consequently, a replacement for the F0 value is proposed in the form of a momentary equivalent time at the reference temperature based on the actual survival pattern of the spores, which need not be log‐linear. This equivalent time can be calculated together with the theoretical survival ratio in real time, thus enabling an operator to monitor the lethality of ongoing industrial heat processes. The concept is demonstrated with published survival data of C. botulinum, for which the Weibullian and log‐logistic models served as primary and secondary models, respectively. The safety factor according to the proposed method is in the number of added minutes of processing, beyond the theoretical time needed to reduce the survival ratio of the targeted spores or cells to a level that would produce practical (or commercial) sterility. Copyright © 2006 Society of Chemical Industry 相似文献
36.
Exfoliation and related microstructures in 2024 aluminum body skins on aging aircraft 总被引:3,自引:0,他引:3
Maria Posada L. E. Murr C. -S. Niou D. Roberson D. Little Roy Arrowood Debra George 《Materials Characterization》1997,38(4-5):259-272
Exfoliation, a directional attack along elongated grain boundaries, has been examined in some detail in rolled 2024 aluminum sheet and plate for KC-135 aging aircraft body skin samples utilizing optical (light) metallography, scanning electron microscopy, and transmission electron microscopy. A detailed analysis and comparison of precipitates within the grains and in the grain boundaries were performed, as well as an examination of elemental depletion profiles across grain boundaries. These observations suggest that corrosion-related anodic sites play a far less significant role in the propagation of exfoliation than do the hard corrosion products creating wedging stresses within the elongated grain boundaries, which seem to demonstrate unique and unusual structural or energetic features or both. 相似文献
37.
Burke M 《Environmental science & technology》1996,30(10):436A
Government. 相似文献
38.
Anna Sztaniszlav Magdolna Balla Maria Farkas-Jahnke Csaba Novák 《Journal of Materials Science》1990,25(5):2353-2358
The kinetics of solid-state reactions of powdered reactants were investigated by X-ray and by differential thermogravimetry in a magnetic field. Measurements revealed mutual diffusion of the Fe3+ and In3+ ions in the Fe2O3-In2O3 system heat treated for 3 h at 700 to 1400° C. Diffusion of indium into the Fe2O3 lattice caused a shift of the Curie temperature of the antiferromagnetic iron oxide towards lower temperatures. Only Caln2O4 was found between CaCO3 and In2O3 up to 1400° C. Also, in the Fe2O3-CaCO3-In2O3in system, the reaction started with the mutual diffusion of iron and indium and the forming of CaFe2O4. End-products were the magnetic -Ca4Fe14O25 and CaFe4O7, and the non-magnetic CaFe5O7, depending on the In3+ concentration. Indium stabilized the magnetic calcium-iron oxide structures, shifting their Curie temperatures towards lower values. 相似文献
39.
Maria da Graça Marcos J.A. Tenreiro MachadoT.-P. Azevedo-Perdicoúlis 《Applied Soft Computing》2012,12(2):589-599
Kinematic redundancy occurs when a manipulator possesses more degrees of freedom than those required to execute a given task. Several kinematic techniques for redundant manipulators control the gripper through the pseudo-inverse of the Jacobian, but lead to a kind of chaotic inner motion with unpredictable arm configurations. Such algorithms are not easy to adapt to optimization schemes and, moreover, often there are multiple optimization objectives that can conflict between them. Unlike single optimization, where one attempts to find the best solution, in multi-objective optimization there is no single solution that is optimum with respect to all indices. Therefore, trajectory planning of redundant robots remains an important area of research and more efficient optimization algorithms are needed. This paper presents a new technique to solve the inverse kinematics of redundant manipulators, using a multi-objective genetic algorithm. This scheme combines the closed-loop pseudo-inverse method with a multi-objective genetic algorithm to control the joint positions. Simulations for manipulators with three or four rotational joints, considering the optimization of two objectives in a workspace without and with obstacles are developed. The results reveal that it is possible to choose several solutions from the Pareto optimal front according to the importance of each individual objective. 相似文献
40.
Maria Buuales Maria Cristina Ballesteros-Briones Manuela Gonzalez-Aparicio Sandra Hervas-Stubbs Eva Martisova Uxua Mancheo Ana Ricobaraza Sara Lumbreras Cristian Smerdou Ruben Hernandez-Alcoceba 《International journal of molecular sciences》2021,22(8)
Immune checkpoint inhibitors (ICIs) have demonstrated remarkable efficacy in a growing number of malignancies. However, overcoming primary or secondary resistances is difficult due to pharmacokinetics issues and side effects associated with high systemic exposure. Local or regional expression of monoclonal antibodies (mAbs) using gene therapy vectors can alleviate this problem. In this work, we describe a high-capacity adenoviral vector (HCA-EFZP-aPDL1) equipped with a mifepristone-inducible system for the controlled expression of an anti-programmed death ligand 1 (PD-L1) blocking antibody. The vector was tested in an immune-competent mouse model of colorectal cancer based on implantation of MC38 cells. A single local administration of HCA-EFZP-aPDL1 in subcutaneous lesions led to a significant reduction in tumor growth with minimal release of the antibody in the circulation. When the vector was tested in a more stringent setting (rapidly progressing peritoneal carcinomatosis), the antitumor effect was marginal even in combination with other immune-stimulatory agents such as polyinosinic-polycytidylic acid (pI:C), blocking mAbs for T cell immunoglobulin, mucin-domain containing-3 (TIM-3) or agonistic mAbs for 4-1BB (CD137). In contrast, macrophage depletion by clodronate liposomes enhanced the efficacy of HCA-EFZP-aPDL1. These results highlight the importance of addressing macrophage-associated immunoregulatory mechanisms to overcome resistance to ICIs in the context of colorectal cancer. 相似文献