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Purpose: This paper aims to analyze the characteristics of friction vibration signals and identify the vibration excitation source at the start and stop stage of microtextured end face of dry gas seals. Design/methodology/approach: The friction pair consists of a diamond-like carbon (DLC) film microtextured seal ring and a spiral groove seal ring. Friction vibration signal feature extraction method based on harmonic wavelet packet and spectrum analysis was proposed. Signals were collected using acceleration sensor, acquisition card and LabVIEW software. Vibration acceleration signal was decomposed into 32 frequency bands using MATLAB wavelet packet transformation. The 32nd band coefficient was extracted for reconstruction, time-domain and spectral waveforms were obtained and spectra before/after denoising were compared. Findings: The end face of the DLC film microtextured seal ring generates a good dynamic pressure effect, and the friction and vibration reduction effects are obvious. The harmonic wavelet packet can decompose the vibration signal conveniently and precisely. In the case of this experiment, the frequency of vibration of the seal ring is 7500 HZ. Originality/value: The results show that the method is effective for the processing of friction vibration signal and the identification of vibration excitation source. The findings will provide ideas for the frictional vibration signal processing and basis for further research in the field of tribology of dry gas seal ring. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2024-0084/ [ABSTRACT FROM AUTHOR]

Purpose: This study aims to research the influence mechanism of microtextured geometric parameters of dry gas seal end face on the tribological behavior under dry frictional conditions. Design/methodology/approach: The microtexture was processed using laser processing, while the diamond-like carbon (DLC) film was applied through magnetron sputtering; the experimental platform of friction vibration was established, the frictional and vibrational properties of different geometric parameters were tested; the data signals of vibrational acceleration and frictional torque were collected and processed using data acquisition instrument. The entropy characteristic parameters of 3D vibrational acceleration were extracted based on wavelet packet decomposition method. The end-face topography was measured with ST400 three-dimensional noncontact surface topography instrument. Findings: The geometry of pits plays a key role in influencing friction performance; the permutation entropy and fuzzy entropy of the vibration acceleration signal changed with variations in microtextured parameters. A textured surface with appropriately size parameters can trap debris, enhance the dynamic pressure effect, reduce impact between the friction interfaces and improve the frictional vibrational performance. In this research, microtextured surface with Φ150 µm-10% and Φ200 µm-5% can effectively reduce friction and vibration between the end faces of a dry gas seal. Originality/value: DLC film improves the hardness of seal ring end face, and microtexture improves the dynamic effect; the tribological behavior monitoring can be realized by analyzing the characteristics of vibration acceleration sensitive parameter with friction state. The findings will provide a basis for further research in the field of tribology and the microtexture optimization of dry gas seal ring end face. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2023-0389/ [ABSTRACT FROM AUTHOR]

Flexible/stretchable strain sensors have attracted much attention due to their advantages for human-computer interaction, smart wearable and human monitoring. However, there are still great challenges on gaining super durability, quick response, and wide sensing range. This paper provides a simple process to obtain a sensor which is based on graphene (GR)/carbon nanotubes (CNTs) and Ecoflex hybrid, which demonstrates superb endurance (over 1000 cycles at 100% strain), remarkable sensitivity (strain over 125% sensitivity up to 20) and wide sensing range (175%). All results indicate that it is capable for human movement monitoring, such as finger and knee bending and pulse beat. Most importantly, it can be used as a warning function for the night cyclist's ride. This research provides the feasibility of using this sensor for practical applications. A stretchable strain sensor takes GR and CNTs as conductive fillers and takes Ecoflex as the substrate through simple ultrasonically mixture and coating process. It can easily match human movement to complete finger and knee bending, pulse beat and breathing monitoring. Furthermore, the application of safety warning for bicycle riders at night has been successfully realized. [ABSTRACT FROM AUTHOR]

Summary: ARF suppresses aberrant cell growth upon c-Myc overexpression by activating p53 responses. Nevertheless, the precise mechanism by which ARF specifically restrains the oncogenic potential of c-Myc without affecting its normal physiological function is not well understood. Here, we show that low levels of c-Myc expression stimulate cell proliferation, whereas high levels inhibit by activating the ARF/p53 response. Although the mRNA levels of ARF are induced in both scenarios, the accumulation of ARF protein occurs only when ULF-mediated degradation of ARF is inhibited by c-Myc overexpression. Moreover, the levels of ARF are reduced through ULF-mediated ubiquitination upon DNA damage. Blocking ARF degradation by c-Myc overexpression dramatically stimulates the apoptotic responses. Our study reveals that ARF stability control is crucial for differentiating normal (low) versus oncogenic (high) levels of c-Myc expression and suggests that differential effects on ULF- mediated ARF ubiquitination by c-Myc levels act as a barrier in oncogene-induced stress responses. [Copyright &y& Elsevier]

Examines the direct interactions between hypoxia-inducible factor 1 alpha (HIF-1 alpha) and Mdm2 modulate p53 function. Response to various types of stress; Protection by HIF-1 alpha of p53 degradation mediated by Mdm2; Implications regarding the molecular mechanism by which p53 is activated by HIF-1 alpha in response to hypoxia; Cell culture and transfection.

The p53 tumour suppressor is a short-lived protein that is maintained at low levels in normal cells by Mdm2-mediated ubiquitination and subsequent proteolysis. Stabilization of p53 is crucial for its tumour suppressor function. However, the precise mechanism by which ubiquitinated p53 levels are regulated in vivo is not completely understood. By mass spectrometry of affinity-purified p53-associated factors, we have identified herpesvirus-associated ubiquitin-specific protease (HAUSP) as a novel p53-interacting protein. HAUSP strongly stabilizes p53 even in the presence of excess Mdm2, and also induces p53-dependent cell growth repression and apoptosis. Significantly, HAUSP has an intrinsic enzymatic activity that specifically deubiquitinates p53 both in vitro and in vivo. In contrast, expression of a catalytically inactive point mutant of HAUSP in cells increases the levels of p53 ubiquitination and destabilizes p53. These findings reveal an important mechanism by which p53 can be stabilized by direct deubiquitination and also imply that HAUSP might function as a tumour suppressor in vivo through the stabilization of p53. [ABSTRACT FROM AUTHOR]

WAP-8294A2 is a cyclic peptide antibiotic with novel structure and excellent activity against Gram-positive pathogens. Herein, we report the total synthesis of complex macrocyclic peptide WAP-8294A2 (W 1) , ent -analogue W 2 , deoxy analogue W 3 and de-methyl analogue W 4 using a solid-phase synthetic route followed by a final stage solution-phase cyclization reaction. Exploitation of this process allowed the synthesis of eleven alanine-scanning analogues and eight lysine-scanning analogues. The antimicrobial activity of these analogues was evaluated in vitro against Gram-positive bacteria. Based on the MIC results, a primary systematic structure-activity relationship has been established. [ABSTRACT FROM AUTHOR]

The frictional vibration performances of textured surface coated with DLC(Diamond-like Carbon)film of dry gas seals ring were investigated. In the meantime, the mechanism of textured surface on interfacial tribological behavior was revealed under dry frictional condition. The acceleration and frictional force were measured by using universal friction and wear tester which type is MMW-1, and the surface topographies were measured by using SEM and ST400 three-dimensional non-contact surface topography instrument. Results show that the textured surface coated with DLC film can significantly improve the tribological behavior of dry gas seal. Textured surface with reasonable size parameters can capture debris and avoid strong impact between the friction pairs, which improves effectively the tribological behavior of interfaces. • The frictional vibration performance of the DLC film textured surface has been researched, the mechanism of tribological behavior has been revealed in this paper. • The effects of the varied geometric parameters of the textured surface on the signal variation of the friction and acceleration of vibration on the interface are investigated, and corresponding regularity has been identified. • The findings of this research provide the foundation for the tribological study of the end face of dry gas seals and optimization of the micro texture structure. [ABSTRACT FROM AUTHOR]

NRF2 (nuclear factor erythroid 2-related factor 2) is a transcription factor which plays a major role in oxidative stress responses by regulating antioxidant gene expression. We have recently identified the ARF tumor suppressor as a key regulator of NRF2. ARF can significantly inhibit NRF2 transcriptional activities, and the ARF-NRF2 interaction may function as a novel checkpoint for oxidative stress responses. [ABSTRACT FROM AUTHOR]

NRF2 (nuclear factor erythroid 2-related factor 2) is a transcription factor which plays a major role in oxidative stress responses by regulating antioxidant gene expression. We have recently identified the ARF tumor suppressor as a key regulator of NRF2. ARF can significantly inhibit NRF2 transcriptional activities, and the ARF-NRF2 interaction may function as a novel checkpoint for oxidative stress responses. [ABSTRACT FROM AUTHOR]

• Human metapneumovirus (HMPV) is an important respiratory pathogen that causes acute respiratory tract infection in children ≤5 years old. • The prevalence peak of HMPV in southern China appeared between March and May. • Respiratory syncytial virus is the most common respiratory virus coinfected with HMPV in children. • The predominant subtype of HMPV in this area is B1, followed by A2c subtype. • Long sunshine duration might decrease the HMPV prevalence. This study aimed to determine the epidemiological and genetic features of human metapneumovirus (HMPV) infection in children in southern China, and the effect of meteorological factors on infection. 14,817 children (≤14 years) with acute respiratory tract infections from 2010 to 2019 were examined for HMPV and other respiratory viruses by real-time quantitative polymerase chain reaction. Full-length F gene of 54 positive samples were sequenced and subjected to phylogenetic analysis. The correlation between the HMPV-positive rate and meteorological factors was analyzed by linear regression analysis. HMPV was detected in 524 (3.5%) children, who were mostly younger than 1 year. The seasonal peak of HMPV prevalence mainly occurred in spring. Respiratory syncytial virus was the most common virus coinfected with HMPV (5.3%). Phylogenetic analysis revealed that the sequenced HMPV strains belonged to four sublineages, including A2b (1.9%), A2c (31.5%), B1 (50.0%), and B2 (16.7%). After adjusting for all meteorological factors, sunshine duration was inversely correlated with the HMPV-positive rate. HMPV is an important respiratory pathogen that causes acute respiratory tract infections in children in southern China, particularly in children ≤5 years old. The prevalence peak of HMPV in this area appeared in spring, and the predominant subtype was B1. Meteorological factors, especially long sunshine duration, might decrease the HMPV prevalence. [ABSTRACT FROM AUTHOR]

Summary Although ARF can suppress tumor growth by activating p53 function, the mechanisms by which it suppresses tumor growth independently of p53 are not well understood. Here, we identified ARF as a key regulator of nuclear factor E2-related factor 2 (NRF2) through complex purification. ARF inhibits the ability of NRF2 to transcriptionally activate its target genes, including SLC7A11, a component of the cystine/glutamate antiporter that regulates reactive oxygen species (ROS)-induced ferroptosis. As a consequence, ARF expression sensitizes cells to ferroptosis in a p53-independent manner while ARF depletion induces NRF2 activation and promotes cancer cell survival in response to oxidative stress. Moreover, the ability of ARF to induce p53-independent tumor growth suppression in mouse xenograft models is significantly abrogated upon NRF2 overexpression. These results demonstrate that NRF2 is a major target of p53-independent tumor suppression by ARF and also suggest that the ARF-NRF2 interaction acts as a new checkpoint for oxidative stress responses. [ABSTRACT FROM AUTHOR]

Shows that the deacetylation of the tumor suppressor and transcriptional factor p53 is mediated by a histone deacetylase-1 (HDAC1)-containing complex. Purification of a p53 target protein which has been identified as a component of the NuRD complex; Results, which show that deacetylation and functional interactions by the PID/MTA2-associated NuRD complex may represent an important pathway to regulate p53 function.

Cytoskeleton has been reported to play an essential role in facilitating the viral life cycle. However, whether the host can exert its antiviral effects by modulating the cytoskeleton is not fully understood. In this study, we identified that host factor DUSP5 was upregulated after dengue virus (DENV) infection. In addition, we demonstrated that overexpression of DUSP5 remarkably inhibited DENV replication. Conversely, the depletion of DUSP5 led to an increase in viral replication. Moreover, DUSP5 was found to restrain viral entry into host cells by suppressing F-actin rearrangement via negatively regulating the ERK-MLCK-Myosin IIB signaling axis. Depletion of dephosphorylase activity of DUSP5 abolished its above inhibitory effects. Furthermore, we also revealed that DUSP5 exhibited broad-spectrum antiviral effects against DENV and Zika virus. Taken together, our studies identified DUSP5 as a key host defense factor against viral infection and uncovered an intriguing mechanism by which the host exerts its antiviral effects through targeting cytoskeleton rearrangement. • DUSP5 retrains viral entry into host cells by suppressing F-actin rearrangement. • DUSP5 negatively regulates the ERK-MLCK-Myosin IIB signaling axis. • DUSP5 exhibits broad-spectrum antiviral effects against dengue virus and Zika virus. [ABSTRACT FROM AUTHOR]

The NAD-dependent deacetylase SIR2 and the forkhead transcription factor DAF-16 regulate lifespan in model organisms, such as yeast and C. elegans. Here we show that the mammalian SIR2 ortholog SIRT1 deacetylates and represses the activity of the forkhead transcription factor Foxo3a and other mammalian forkhead factors. This regulation appears to be in the opposite direction from the genetic interaction of SIR2 with forkhead in C. elegans. By restraining mammalian forkhead proteins, SIRT1 also reduces forkhead-dependent apoptosis. The inhibition of forkhead activity by SIRT1 parallels the effect of this deacetylase on the tumor suppressor p53. We speculate how downregulating these two classes of damage-responsive mammalian factors may favor long lifespan under certain environmental conditions, such as calorie restriction. [Copyright &y& Elsevier]

Although Mdm2-mediated ubiquitination is essential for both degradation and nuclear export of p53, the molecular basis for the differential effects of Mdm2 remains unknown. Here we show that low levels of Mdm2 activity induce monoubiquitination and nuclear export of p53, whereas high levels promote p53's polyubiquitination and nuclear degradation. A p53-ubiquitin fusion protein that mimics monoubiquitinated p53 was found to accumulate in the cytoplasm in an MdmZ-independent manner, indicating that monoubiquitination is critical for p53 trafficking. These results clarify the nature of ubiquitination-mediated p53 regulation and suggest that distinct mechanisms regulate p53 function in accordance with the levels of Mdm2 activity. [ABSTRACT FROM AUTHOR]