A smart process controller framework for Industry 4.0 settings

This paper presents a smart supervisory framework for a single process controller, designed for Industry 4.0 shop floors. This digitization of a full supervisory suite for a single process controller enables self-awareness, self-diagnosis, self-prognosis, and self-healing (by definition, these "self" elements are missing from other supervisory frameworks diagnosing numerous controllers in parallel). The proposed framework is aligned with the concept of a Cyber Physical System (CPS), since its implementation generates a rich cyber physical entity of the controlled process. This CPS entity can either be considered as the process digital twin, or can provide a solid basis for generating it. Finally, the framework includes the main characteristics of Industry 4.0, such as advanced use of Artificial Intelligence (AI) and big data analysis. The framework is based on four modules: (1) Control and Awareness module—performing both continuous process control and adjustments, as well as machine learning (ML) and statistical process control (SPC) for identifying abnormalities that require further diagnosis; (2) Process -diagnosis module—performing continual (recurrent) analysis of the process state and trends; (3) Prognosis and Healing module—performing prognosis and automated intervention via parameter changes, re-configurations, and automated maintenance; (4) External Interaction Platform—an interactive module for interfacing with experts, presenting them with the process analysis information and obtaining feedback from them as part of a learning process. Using an implementation showcase to illustrate the methodological framework’s applicability, we demonstrate its real-world potential. The proposed framework could serve as a guide for implementing smart process control and maintenance systems in Industry 4.0 shop floors. It could also provide a firm basis for comparison with future suggested frameworks. Future research directions could include pursuing improvements to the proposed process control framework and validating the framework by case studies of its implementation.

     

Recurrent Epstein-Barr virus-associated lesions in organ transplant recipients

This paper discusses the problem of violence and its expression upon mortality due to external causes. A few indicators are offered, which have been worked upon it to emphasise the importance of the theme. In a general way, the study demonstrates violent death has had its magnitude increased along the years, not only throughout Latin America but also in Brazil and in Santa Catarina.     

Cathepsin E expression by normal and premalignant cervical epithelium

We have investigated the expression of the aspartic proteinase cathepsin E and HLA-DR and the presence of HPV16 in normal squamous epithelium (n = 8) and low-grade (n = 21) and high-grade (n = 14) intraepithelial squamous lesions of the uterine cervix. Immunohistochemistry of cervical biopsies revealed that up-regulation of cathepsin E expression was related to increasing severity of the cervical intraepithelial neoplasia (CIN). Up-regulation of protein was associated with increased message as assessed by in situ hybridization. Langerhans cells and the majority of koilocytes did not express detectable cathepsin E levels. Although there was also an up-regulation of HLA-DR expression by cervical keratinocytes in cervical intraepithelial neoplasia lesions, as determined by immunohistochemistry, no significant correlation was found between HLA-DR and cathepsin E expression in these lesions; neither was expression of cathepsin E correlated to the presence of HPV16, detected by polymerase chain reaction. The expression of cathepsin E, an aspartic proteinase that is reported to play a role in antigen processing for presentation by class II major histocompatibility complex molecules, is associated with cellular dedifferentiation in cervical intraepithelial neoplasia.     

最快晶体管的频率接近太赫兹

Robert J.Mears是用于宽带互联网的铒掺杂光纤放大器(EDFA)的发明者。他在寻找将光器件和波导结合到硅中的方法时,发现了一个有趣的结果:一种特殊的硅超晶格结构可以加速某一个     

Glucocorticoids and aging

In this review we analyze the morphologic changes, hypothalamic-pituitary-adrenal (HPA) axis functions, glucocorticoid (GC) receptors, and steroidogenic enzyme activities in both animals and humans during aging. In rodent studies, older animals tend to show: 1) hypertrophy of adrenal zona fasciculata (ZF) cells; 2) neuronal loss in the hypothalamic area; 3) loss of GC receptors in the hippocampus; 4) raised circulating adrenocorticotropic hormone (ACTH) and GC levels, and increased release of corticotropin-releasing hormone from the hypothalamus; 5) reduced suppression of endogenous GC secretion after administration of dexamethasone; 6) decreased attenuation of response to chronic stress; and 7) increased activity of P450scc and 21-hydroxylase. According to the GC cascade hypothesis, stress and GCs facilitate the aging process in rats. Stress induces downregulation of GC receptors in the hippocampus, then impairs GC feedback on stress-induced HPA axis activation. Finally, an increase in the basal level of corticosterone and extended GC secretion following stress occurs. Because activation of the hippocampus decreases HPA axis function, the unrestrained elevation of GC concentration and the reduction in the level of GC receptors in the hippocampus may gradually weaken the feedback mechanisms and halt the response to stress. In humans, there are conflicting reports of HPA axis function during aging, so it is difficult to make a final conclusion regarding the relationship between aging and HPA axis function.     

Variables affecting results of sodium chloride tolerance test for identification of rapidly growing mycobacteria

The sodium chloride tolerance test is often used in the identification of rapidly growing mycobacteria, particularly for distinguishing between Mycobacterium abscessus and Mycobacterium chelonae. This test, however, is frequently unreliable for the identification of some species. In this study we examined the following variables: medium manufacturer, inoculum concentration, and atmosphere and temperature of incubation. Results show that reliability is improved if the test and control slants are inoculated with an organism suspension spectrophotometrically equal to a 1 McFarland standard. Slants should be incubated at 35 degrees C in ambient air and checked weekly for 4 weeks. Growth on control slants should be critically evaluated to determine the adequacy of the inoculum; colonies should number greater than 50. Salt-containing media should be examined carefully to detect pinpoint or tiny colonies, and colonies should number greater than 50 for a positive reaction. Concurrent use of a citrate slant may be helpful for distinguishing between M. abscessus and M. chelonae. Molecular methodologies are probably the most reliable means for the identification of rapidly growing mycobacteria and should be used, if possible, when unequivocal species identification is of particular importance.     

Mutational analysis of the pea phytochrome A chromophore pocket: chromophore assembly with apophytochrome A and photoreversibility

Ten site-specific mutants of pea apophytochrome A were expressed in Saccharomyces cerevisiae and analyzed for chromophore assembly with apoprotein and photoreversible absorbance changes. The mutants constitute two specific changes for each of five conserved amino acid residues located in the microenvironment of the chromophore attachment residue, which is Cys-323 in pea phytochrome A. All mutant apophytochromes were autocatalytically able to covalently attach phycocyanobilin, indicating that there were no major structural perturbations in the apoproteins. However, the rate of chromophore ligation varied significantly among the mutants. Spectrally, the mutant holophytochromes are of three types: mutant phytochromes that are indistinguishable from the wild-type adduct, mutants with blue-shifted Pr and Pfr absorption maxima compared to the wild-type adduct, and mutants that are not photoreversible. From an analysis of the results, we concluded that the residues Asp-309, Arg-318, His-321, and Gln-326 are probably not catalytically involved in the chromophore ligation reaction, but some residues may play significant structural and stereochemical roles. Arg-318 might anchor the chromophore, as has been suggested [Partis, M. D., & Grimm, R. (1990) Z. Naturforsch, 45c, 987-998; Parker, W., et al. (1993) Bioconjugate Chem. (in press)]. The conserved Gln-326, three residues downstream from the chromophore attachment site, is not electrostatically critical for the spectral integrity and photoreversibility of phytochrome, but this residue is sterically important to the lyase activity. It appears that the role of the five amino acid residues in the N- and C-terminal vicinities of the chromophore binding Cys-323 is structural rather than catalytic for the ligation reaction.     

B7 blockade prevents activation-induced cell death of thymocytes

Although both B7 and its counter-receptor CD28 are expressed in the thymus, the role of B7 in thymic selection is not clear. We investigated the role of B7 in intrathymic deletion of antigen-specific T cells using a TCR transgenic model specific for antigen ovalbumin (OVA) and H-2Ad. Intraperitoneal injection of OVA induced apoptosis of thymocytes and drastic reduction of thymocyte numbers. This was significantly inhibited by co-injection of CTLA-4-Ig which blocks B7 co-stimulation. Deletion of T cells in the thymus following i.p. injection of OVA was associated with T cell pre-activation as demonstrated by T cell proliferation and cytokine production. Injection of CTLA-4-Ig blocked all these activation events and rescued thymocytes from activation-induced cell death. These results demonstrate that B7 is required for the activation-induced cell death of MHC class II-restricted thymocytes in vivo.     

The two steps of group II intron self-splicing are mechanistically distinguishable

The two transesterification reactions catalyzed by self-splicing group II introns take place in either two active sites or two conformations of a single active site involving rearrangements of the positions of the reacting groups. We have investigated the effects on the rates of the chemical steps of the two reactions due to sulfur substitution of nonbridging oxygens at both the 5' and 3' splice sites as well as the deoxyribose substitution of the ribose 2' hydroxyl group at the 5' splice site. The data suggest that the two active sites differ in their interactions with several of these groups. Specifically, sulfur substitution of the pro-Sp nonbridging oxygen at the 5' splice site reduces the chemical rate of the step one branching reaction by at least 250-fold, whereas substitution of the pro-Sp oxygen at the 3' splice site has only a 4.5-fold effect on the chemical rate of step two. Previous work demonstrated that the Rp phosphorothioate substitutions at both the 5' and 3' splice sites reduced the rate of both steps of splicing to an undetectable level. These results suggest that either two distinct active sites catalyze the two steps or that more significant alterations must be made in a single bifunctional active site to accommodate the two different reactions.