The present paper describes an experimental setup and an associated calculation procedure in order to measure and predict the electric impedance of rolling bearings, in order to use it as a sensor ...model for measuring bearing loads. Based on the state of research, relevant influences on the electric impedance of a rolling bearing are not taken into account in the models known to the author. These influencing factors are added by an approach which takes unloaded rolling elements and the undeflected area of loaded rolling elements into account. A comparison between experimental results and the adapted theory shows that the consideration of unloaded rolling elements in the bearing model improves the predictions made compared to the state of the art. Nevertheless a difference between measurement and calculation remains, which is addressed by pointing out approaches to further reduce this discrepancy.
•Consideration of unloaded rolling elements in the electric model of rolling bearings.•Validation of the improved electric model.•Suitability evaluation as a model for force measurement.•Notes on further influencing factors.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In the fullerene cone HIV-1 capsid, the central channels of the hexameric and pentameric capsomers each contain a ring of arginine (Arg18) residues that perform essential roles in capsid assembly and ...function. In both the hexamer and pentamer, the Arg18 rings coordinate inositol hexakisphosphate, an assembly and stability factor for the capsid. Previously, it was shown that amino-acid substitutions of Arg18 can promote pentamer incorporation into capsid-like particles (CLPs) that spontaneously assemble in vitro under high-salt conditions. Here, we show that these Arg18 mutant CLPs contain a non-canonical pentamer conformation and distinct lattice characteristics that do not follow the fullerene geometry of retroviral capsids. The Arg18 mutant pentamers resemble the hexamer in intra-oligomeric contacts and form a unique tetramer-of-pentamers that allows for incorporation of an octahedral vertex with a cross-shaped opening in the hexagonal capsid lattice. Our findings highlight an unexpected degree of structural plasticity in HIV-1 capsid assembly.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The HIV-1 capsid is a fullerene cone made of quasi-equivalent hexamers and pentamers of the viral CA protein. Typically, quasi-equivalent assembly of viral capsid subunits is controlled by a ...molecular switch. Here, we identify a Thr-Val-Gly-Gly motif that modulates CA hexamer/pentamer switching by folding into a 3
helix in the pentamer and random coil in the hexamer. Manipulating the coil/helix configuration of the motif allowed us to control pentamer and hexamer formation in a predictable manner, thus proving its function as a molecular switch. Importantly, the switch also remodels the common binding site for host factors that are critical for viral replication and the new ultra-potent HIV-1 inhibitor lenacapavir. This study reveals that a critical assembly element also modulates the post-assembly and viral replication functions of the HIV-1 capsid and provides new insights on capsid function and inhibition.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
Correlative fluorescence and electron microscopy (CFEM) is a multimodal technique that combines dynamic and localization information from fluorescence methods with ultrastructural data from electron ...microscopy, to give new information about how cellular components change relative to the spatiotemporal dynamics within their environment. In this review, we will discuss some of the basic techniques and tools of the trade for utilizing this attractive research method, which is becoming a very powerful tool for biology labs. The information obtained from correlative methods has proven to be invaluable in creating consensus between the two types of microscopy, extending the capability of each, and cutting the time and expense associated with using each method separately for comparative analysis. The realization of the advantages of these methods in cell biology has led to rapid improvement in the protocols and has ushered in a new generation of instruments to reach the next level of correlation--integration.
Various methods for calculating the capacitance of unloaded rolling elements are compared to improve the electric characterization of rolling element bearings. Semi-analytical approximations and ...finite element simulations are applied and a closed-form analytical two-dimensional solution is derived for comparison. The results show that the most common semi-analytical approximation, which uses effective radii to express the contact geometry, reproduces the trend from numerical and analytical calculations, but overestimates the results derived from numerical simulations. Another semi-analytical approach is presented that delivers better results for the capacitance of unloaded point contacts.
•Comparison of possible methods to calculate the capacitance of unloaded rolling elements: semi-analytical and numerical methods.•Derivation of an analytic 2D formula for calculating the capacitance per length unit of an unloaded ball-raceway contact.•Comparison of multiple interpretations of the semi-analytical capacitance calculation.•Including the rim area aside of the groove into the capacitance calculation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The neurocognitive mechanism underlying negation processing remains controversial. While negation is suggested to modulate the access of word meaning, no such evidence has been observed in the ...event‐related potential (ERP) literature on sentence processing. In the current study, we applied both univariate ERP and multivariate pattern analysis (MVPA) methods to examine the processing of sentence negation. We investigated two types of negative congruent/incongruent sentence pairs with truth‐value evaluation (e.g., “A robin is a/not a bird”) and without (e.g., “The woman reads a/no book”). In the N400 time window, ERPs consistently showed increased negativity for negative and incongruent conditions. MVPA, on the other hand, revealed nuanced interactions between polarity and congruency. In the later P600 time window, MVPA but not the ERPs revealed an effect of congruency, which may be functionally distinct from the N400 window. We further used cross‐decoding to show that the cognitive processes underlying the N400 window for both affirmative and negative sentences are comparable, whereas in the P600 window, only for the truth sentences, negative sentences showed a distinct pattern from their affirmative counterparts. Our results thus speak for a more interactive, but nevertheless serial and biphasic, and potentially construction‐specific processing account of negation. We also discuss the advantage of applying MVPA in addition to the classical univariate methods for a better understanding of the neurobiology of negation processing and language comprehension alike.
This study for the first time investigates sentence negation using multivariate pattern analysis (MVPA) methods. It shows that when decoding semantically congruent versus incongruent words, negation modulates this process within the N400 time window. MVPA also reveals a late processing window of sentence negation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Polycrystalline
γ
-
γ
′ superalloys with varying grain sizes and unimodal, bimodal, or trimodal distributions of precipitates have been studied. To assess the contributions of specific features of ...the microstructure to the overall strength of the material, a model that considers solid-solution strengthening, Hall–Petch effects, precipitate shearing in the strong and weak pair-coupled modes, and dislocation bowing between precipitates has been developed and assessed. Cross-slip-induced hardening of the Ni
3
Al phase and precipitate size distributions in multimodal microstructures are also considered. New experimental observations on the contribution of precipitate shearing to the peak in flow stress at elevated temperatures are presented. Various alloys having comparable yield strengths were investigated and were found to derive their strength from different combinations of microconstituents (mechanisms). In all variants of the microstructure, there is a strong effect of antiphase boundary (APB) energy on strength. Materials subjected to heat treatments below the
γ
′ solvus temperature benefit from a strong Hall–Petch contribution, while supersolvus heat-treated materials gain the majority of their strength from their resistance to precipitate shearing.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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