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301.
Using predictive and proactive maintenance methods for critical equipment and processes in industry can help reduce unplanned downtimes and improve process availability and stability. Artificial intelligence (AI) methods for process data analysis can provide plant operators with much-needed insights for decision support and predictive plant maintenance strategies. In this article, a guideline for implementing AI methods in the process industry is provided using the AI-based application Siemens Predictive Analytics (SiePA) and the results of a SiePA application in a milling process are presented. 相似文献
302.
Christine G. Stoehr Elke Nolte Sven Wach Wolf F. Wieland Ferdinand Hofstaedter Arndt Hartmann Robert Stoehr 《International journal of molecular sciences》2012,13(9):10959-10969
NAD(P)H:quinone oxidoreductase 1 (NQO1) catalyses the reduction of quinoid compounds to hydroquinones, preventing the generation of free radicals and reactive oxygen. A “C” to “T” transversion at position 609 of NQO1, leading to a nonsynonymous amino acid change (Pro187Ser, P187S), results in an altered enzyme activity. No NQO1 protein activity was detected in NQO1
609TT genotype, and low to intermediate activity was detected in NQO1
609CT genotype compared with 609CC genotype. Thus, this polymorphism may result in altered cancer predisposition. For prostate cancer, only sparse data are available. We therefore analyzed the distribution of the NQO1 P187S SNP (single nucleotide polymorphism) in prostate cancer patients and a healthy control group. Allelic variants were determined using RFLP analysis. Overall, 232 patients without any malignancy and 119 consecutive prostate cancer patients were investigated. The genotype distribution in our cohorts followed the Hardy–Weinberg equilibrium in cases and controls. The distribution of the NQO1 codon 187 SNP did not differ significantly between prostate cancer patients and the control group (p = 0.242). There was also no association between the allelic variants and stage or Gleason score of the tumors. The NQO1 P187S SNP was not significantly associated with an increased prostate cancer risk in our cohorts. The SNP has also no influence on histopathological characteristics of the tumors. A combined analysis of all available data from published European studies also showed no significant differences in the genotype distribution between controls and prostate cancer patients. Our data suggest a minor role of the NQO1 nucleotide 609 polymorphism in prostate carcinogenesis. 相似文献
303.
Jannik Richter Ferdinand Lange Thomas Scheper Dörte Solle Sascha Beutel 《化学,工程师,技术》2023,95(4):498-510
The digitalization of processes is one of the currently dominating topics and missions in both industrial production and scientific research. In biotechnology, these efforts have enormous potential to optimize existing bioprocesses or to develop new bioprocesses for upcoming challenges. In this review, the state-of-art of digitalization in bioprocess engineering is considered, the terms digital twin and digital shadow are characterized, and an outlook on future Lab 4.0 concepts is given. 相似文献
304.
Karen Butina Linda Lantz Ferdinand X. Choong Ana Tomac Hamid Shirani Susanne Löffler K. Peter R. Nilsson Agneta Richter-Dahlfors 《Chembiochem : a European journal of chemical biology》2022,23(11):e202100684
Optotracers are conformation-sensitive fluorescent tracer molecules that detect peptide- and carbohydrate-based biopolymers. Their binding to bacterial cell walls allows selective detection and visualisation of Staphylococcus aureus (S. aureus). Here, we investigated the structural properties providing optimal detection of S. aureus. We quantified spectral shifts and fluorescence intensity in mixes of bacteria and optotracers, using automatic peak analysis, cross-correlation, and area-under-curve analysis. We found that the length of the conjugated backbone and the number of charged groups, but not their distribution, are important factors for selective detection of S. aureus. The photophysical properties of optotracers were greatly improved by incorporating a donor-acceptor-donor (D-A-D)-type motif in the conjugated backbone. With significantly reduced background and binding-induced on-switch of fluorescence, these optotracers enabled real-time recordings of S. aureus growth. Collectively, this demonstrates that chemical structure and photophysics are key tunable characteristics in the development of optotracers for selective detection of bacterial species. 相似文献
305.
Patrick Pingel Achmad Zen Ruben D. Abellón Ferdinand C. Grozema Laurens D.A. Siebbeles Dieter Neher 《Advanced functional materials》2010,20(14):2286-2295
Previous investigations of the field‐effect mobility in poly(3‐hexylthiophene) (P3HT) layers revealed a strong dependence on molecular weight (MW), which was shown to be closely related to layer morphology. Here, charge carrier mobilities of two P3HT MW fractions (medium‐MW: Mn = 7 200 g mol?1; high‐MW: Mn = 27 000 g mol?1) are probed as a function of temperature at a local and a macroscopic length scale, using pulse‐radiolysis time‐resolved microwave conductivity (PR‐TRMC) and organic field‐effect transistor measurements, respectively. In contrast to the macroscopic transport properties, the local intra‐grain mobility depends only weakly on MW (being in the order of 10?2 cm2 V?1 s?1) and being thermally activated below the melting temperature for both fractions. The striking differences of charge transport at both length scales are related to the heterogeneity of the layer morphology. The quantitative analysis of temperature‐dependent UV/Vis absorption spectra according to a model of F. C. Spano reveals that a substantial amount of disordered material is present in these P3HT layers. Moreover, the analysis predicts that aggregates in medium‐MW P3HT undergo a “pre‐melting” significantly below the actual melting temperature. The results suggest that macroscopic charge transport in samples of short‐chain P3HT is strongly inhibited by the presence of disordered domains, while in high‐MW P3HT the low‐mobility disordered zones are bridged via inter‐crystalline molecular connections. 相似文献
306.
Alamin Mansouri Ferdinand Deger Marius Pedersen Jon Y. Hardeberg Yvon Voisin 《Signal, Image and Video Processing》2016,10(3):447-454
Poisson distributed noise, such as photon noise, is an important noise source in multi- and hyperspectral images. We propose a variational-based denoising approach that accounts the vectorial structure of a spectral image cube, as well as the Poisson distributed noise. For this aim, we extend an approach initially developed for monochromatic images, by a regularisation term, which is spectrally and spatially adaptive and preserves edges. In order to take the high computational complexity into account, we derive a split Bregman optimisation for the proposed model. The results show the advantages of the proposed approach compared with a marginal approach on synthetic and real data. 相似文献
307.
María C. Glvez‐Rueda Paramvir Ahlawat Lena Merten Farzaneh Jahanbakhshi Marko Mladenovi Alexander Hinderhofer M. Ibrahim Dar Yang Li Algirdas Du
inskas Brian Carlsen Wolfgang Tress Amita Ummadisingu Shaik M. Zakeeruddin Frank Schreiber Anders Hagfeldt Ursula Rothlisberger Ferdinand C. Grozema Jovana V. Mili Michael Graetzel 《Advanced functional materials》2020,30(38)
Layered hybrid perovskites have emerged as a promising alternative to stabilizing hybrid organic–inorganic perovskite materials, which are predominantly based on Ruddlesden‐Popper structures. Formamidinium (FA)‐based Dion‐Jacobson perovskite analogs are developed that feature bifunctional organic spacers separating the hybrid perovskite slabs by introducing 1,4‐phenylenedimethanammonium (PDMA) organic moieties. While these materials demonstrate competitive performances as compared to other FA‐based low‐dimensional perovskite solar cells, the underlying mechanisms for this behavior remain elusive. Here, the structural complexity and optoelectronic properties of materials featuring (PDMA)FAn–1PbnI3n+1 (n = 1–3) formulations are unraveled using a combination of techniques, including X‐ray scattering measurements in conjunction with molecular dynamics simulations and density functional theory calculations. While theoretical calculations suggest that layered Dion‐Jacobson perovskite structures are more prominent with the increasing number of inorganic layers (n), this is accompanied with an increase in formation energies that render n > 2 compositions difficult to obtain, in accordance with the experimental evidence. Moreover, the underlying intermolecular interactions and their templating effects on the Dion‐Jacobson structure are elucidated, defining the optoelectronic properties. Consequently, despite the challenge to obtain phase‐pure n > 1 compositions, time‐resolved microwave conductivity measurements reveal high photoconductivities and long charge carrier lifetimes. This comprehensive analysis thereby reveals critical features for advancing layered hybrid perovskite optoelectronics. 相似文献