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31.
The paper presents a computationally effective method for fault detection. A system’s responses are measured under healthy and ill conditions. These signals are used to calculate so-called signature functions that create a signal space. The current system’s response is projected into this space. The signal location in this space easily allows to determine the fault. No classifier such as a neural network, hidden Markov models, etc. is required. The advantage of this proposed method is its efficiency, as computing projections amount to calculating dot products. Therefore, this method is suitable for real-time embedded systems due to its simplicity and undemanding processing capabilities which permit the use of low-cost hardware and allow rapid implementation. The approach performs well for systems that can be considered linear and stationary. The communication presents an application, whereby an industrial process of moulding is supervised. The machine is composed of forms (dies) whose alignment must be precisely set and maintained during the work. Typically, the process is stopped periodically to manually control the alignment. The applied algorithm allows on-line monitoring of the device by analysing the acceleration signal from a sensor mounted on a die. This enables to detect failures at an early stage thus prolonging the machine’s life. 相似文献
32.
MOFOID is a new server developed mainly for automated modeling of protein structures by their homology to the structures deposited in the PDB database. Selection of a template and calculation of the alignment is performed with the Smith-Waterman or Needleman-Wunsch algorithms implemented in the EMBOSS package. The final model is built and optimised with programs from the JACKAL package. The wide spectrum of options in the web-based interface and the possibility of uploading user's own alignment make MOFOID a suitable platform for testing new approaches in the alignment building. The server is available at https:// valis.ibb.waw.pl/mofoid/. 相似文献
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Bobrowicz P Davidson RC Li H Potgieter TI Nett JH Hamilton SR Stadheim TA Miele RG Bobrowicz B Mitchell T Rausch S Renfer E Wildt S 《Glycobiology》2004,14(9):757-766
A significant percentage of eukaryotic proteins contain posttranslationalmodifications, including glycosylation, which are required forbiological function. However, the understanding of the structurefunctionrelationships of N-glycans has lagged significantly due to themicroheterogeneity of glycosylation in mammalian produced proteins.Recently we reported on the cellular engineering of yeast toreplicate human N-glycosylation for the production of glycoproteins.Here we report the engineering of an artificial glycosylationpathway in Pichia pastoris blocked in dolichol oligosaccharideassembly. The PpALG3 gene encoding Dol-P-Man:Man5GlcNAc2-PP-Dolmannosyltransferase was deleted in a strain that was previouslyengineered to produce hybrid GlcNAcMan5GlcNAc2 human N-glycans.Employing this approach, combined with the use of combinatorialgenetic libraries, we engineered P. pastoris strains that synthesizecomplex GlcNAc2Man3GlcNAc2 N-glycans with striking homogeneity.Furthermore, through expression of a Golgi-localized fusionprotein comprising UDP-glucose 4-epimerase and ß-1,4-galactosyltransferase activities we demonstrate that this structure isa substrate for highly efficient in vivo galactose addition.Taken together, these data demonstrate that the artificial invivo glycoengineering of yeast represents a major advance inthe production of glycoproteins and will emerge as a practicaltool to systematically elucidate the structurefunctionrelationship of N-glycans.
1 These authors contributed equally to this work. 2 To whom correspondence should be addressed; e-mail: swildt{at}glycofi.com 相似文献
36.
Li H Sethuraman N Stadheim TA Zha D Prinz B Ballew N Bobrowicz P Choi BK Cook WJ Cukan M Houston-Cummings NR Davidson R Gong B Hamilton SR Hoopes JP Jiang Y Kim N Mansfield R Nett JH Rios S Strawbridge R Wildt S Gerngross TU 《Nature biotechnology》2006,24(2):210-215
As the fastest growing class of therapeutic proteins, monoclonal antibodies (mAbs) represent a major potential drug class. Human antibodies are glycosylated in their native state and all clinically approved mAbs are produced by mammalian cell lines, which secrete mAbs with glycosylation structures that are similar, but not identical, to their human counterparts. Glycosylation of mAbs influences their interaction with immune effector cells that kill antibody-targeted cells. Here we demonstrate that human antibodies with specific human N-glycan structures can be produced in glycoengineered lines of the yeast Pichia pastoris and that antibody-mediated effector functions can be optimized by generating specific glycoforms. Glycoengineered P. pastoris provides a general platform for producing recombinant antibodies with human N-glycosylation. 相似文献
37.
Environmental stress correlates with increases in both genetic and residual variances: A meta‐analysis of animal studies 下载免费PDF全文
Piotr K. Rowiński Björn Rogell 《Evolution; international journal of organic evolution》2017,71(5):1339-1351
Adaptive evolutionary responses are determined by the strength of selection and amount of genetic variation within traits, however, both are known to vary across environmental conditions. As selection is generally expected to be strongest under stressful conditions, understanding how the expression of genetic variation changes across stressful and benign environmental conditions is crucial for predicting the rate of adaptive change. Although theory generally predicts increased genetic variation under stress, previous syntheses of the field have found limited support for this notion. These studies have focused on heritability, which is dependent on other environmentally sensitive, but nongenetic, sources of variation. Here, we aim to complement these studies with a meta‐analysis in which we examine changes in coefficient of variation (CV) in maternal, genetic, and residual variances across stressful and benign conditions. Confirming previous analyses, we did not find any clear direction in how heritability changes across stressful and benign conditions. However, when analyzing CV, we found higher genetic and residual variance under highly stressful conditions in life‐history traits but not in morphological traits. Our findings are of broad significance to contemporary evolution suggesting that rapid evolutionary adaptive response may be mediated by increased evolutionary potential in stressed populations. 相似文献
38.
Jan Bocianowski Piotr Szulc Agnieszka Wakiewicz Kamila Nowosad Joanna Kobus‐Cisowska 《Journal of Phytopathology》2019,167(9):516-526
Mycotoxins are secondary metabolites produced by many filamentous fungi, such as Fusarium, and are widespread in nature and can adversely affect almost all organisms. Mycotoxins can be formed in very different conditions such as when plants are growing or in crops that are stored in improper conditions. One of the methods to prevent the formation of mycotoxins in powdered feed is using varieties of appropriate quality and proper mineral fertilization, primarily nitrogen. In this study, the concentration of ergosterol and mycotoxins in the kernels of two maize cultivars from different maturity groups in Poland during the harvest of 2011 and 2012 was investigated using HPLC methods. We aimed to analyse the concentration of ergosterol as a fungal biomass indicator and mycotoxins from two maize cultivars under six different forms of nitrogen fertilizers. The “stay‐green” hybrid ES Paroli was characterized by a significantly lower ergosterol and the ability to accumulate the mycotoxins, compared to the classic cultivar ES Palazzo. The varieties of maize that remain green for a longer time period, the so‐called stay‐green type, are characterized by a different coefficient of nitrogen remobilization compared to the classic hybrids. Their dynamics of growth and accumulation of nutrients indicates a nitrogen fertilization system, indicating that slow‐release fertilizers are potentially more adapted to the cycles of maize vegetation. Hence, compared to the classic variant, the “stay‐green” variety uses nitrogen more effectively from mineral fertilizers. Such hybrids are healthier and remain in good condition for a longer time; therefore, they are characterized by a lower pathogen pressure. Thus, the cultivation of such varieties can be considered as one of the elements of integrated maize production. We observed identical reactions of the studied experimental factors for both vegetation seasons, which indicates the lack of environmental impact on the functioning and interaction of experimental factors. 相似文献
39.
Monensin A methyl ester complexes with Li+, Na+, and K+ cations studied by ESI-MS, 1H- and 13C-NMR, FTIR, as well as PM5 semiempirical method 总被引:1,自引:0,他引:1
Monensin A methyl ester (MON1) was synthesized by a new method and its ability to form complexes with Li+, Na+, and K+ cations was studied by electrospray ionization-mass spectroscopy (ESI-MS), 1H and 13C nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), and PM5 semiempirical methods. It is shown that MON1 with monovalent metal cations forms stable complexes of 1:1 stoichiometry. The structures of the complexes are stabilized by intramolecular hydrogen bonds in which the OH groups are always involved. In the structure of MON1, the oxygen atom of the C=O ester group is involved in very weak bifurcated intramolecular hydrogen bonds with two hydroxyl groups, whereas in the complexes of MON1 with monovalent metal cations the C=O ester group is not engaged in any intramolecular hydrogen bonds. Furthermore, it is demonstrated that the strongest intramolecular hydrogen bonds are formed within the MON1-Li+ complex structure. The structures of the MON1 and its complexes with Li+, Na+, and K+ cations are visualized and discussed in detail. 相似文献
40.
Piotr Szymczak 《Journal of molecular biology》2009,390(3):443-2239
Mechanical forces govern physiological processes in all living organisms. Many cellular forces, for example, those generated in cyclic conformational changes of biological machines, have repetitive components. In apparent contrast, little is known about how dynamic protein structures respond to periodic mechanical information. Ubiquitin is a small protein found in all eukaryotes. We developed molecular dynamics simulations to unfold single and multimeric ubiquitins with periodic forces. By using a coarse-grained representation, we were able to model forces with periods about 2 orders of magnitude longer than the protein's relaxation time. We found that even a moderate periodic force weakened the protein and shifted its unfolding pathways in a frequency- and amplitude-dependent manner. A complex dynamic response with secondary structure refolding and an increasing importance of local interactions was revealed. Importantly, repetitive forces with broadly distributed frequencies elicited very similar molecular responses compared to fixed-frequency forces. When testing the influence of pulling geometry on ubiquitin's mechanical stability, it was found that the linkage involved in the mechanical degradation of cellular proteins renders the protein remarkably insensitive to periodic forces. We also devised a complementary kinetic energy landscape model that traces these observations and explains periodic-force, single-molecule measurements. In turn, this analytical model is capable of predicting dynamic protein responses. These results provide new insights into ubiquitin mechanics and a potential mechanical role during protein degradation, as well as first frameworks for dynamic protein stability and the modeling of repetitive mechanical processes. 相似文献