Enhancing cutting tool sustainability based on remaining useful life prediction

As a critical part of machining, cutting tools are of great importance to sustainability enhancement. Normally, they are underused, resulting in huge waste. However, the lack of reliable support leads to a high risk on improving the cutting tool utilization. Aiming at this problem, this paper proposes an approach to enhance the cutting tool sustainability. A non-linear cutting tool remaining useful life prediction model is developed based on tool wear historical data. Probability distribution function and cumulative distribution function are used to quantize the uncertainty of the prediction. Under a constant machining condition, a cutting tool life is extended according to its specific remaining useful life prediction, rather than a unified one. Under various machining conditions, machining parameters are optimized to improve efficiency or capability. Cutting tool sustainability is assessed in economic, environmental and social dimensions. Experimental study verifies that both material removal rate and material removal volume are improved. Carbon emission and cutting tool cost are also reduced. The balance between benefit and risk is achieved by assigning a reasonable confidence level. Cutting tool sustainability can be enhanced by improving cutting tool utilization at controllable risk.©2020 Elsevier. This manuscript version is made available under the Creative Commons Attribution–NonCommercial–NoDerivatives 4.0 International (CC BY–NC–ND 4.0) license, https://creativecommons.org/licenses/by-nc-nd/4.0/fi=vertaisarvioitu|en=peerReviewed

Differential expression of lymphocyte subpopulations in the peripheral blood of patients with COVID‐19: Implications for disease severity and prognosis

Abstract Objective To investigate the expression patterns and clinical significance of specific lymphocyte subsets in the peripheral blood of patients with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. Methods Between December 2022 and February 2023, a cohort of 165 patients from the First Affiliated Hospital of Guangzhou University of Chinese Medicine were analyzed. The participants represented various stages of coronavirus infection severity: mild, moderate, severe, and critical. Additionally, 40 healthy individuals constituted the control group. The FC 500MPL flow cytometer and associated reagents for flow cytometry. Results Compared with the healthy control group, activated B lymphocytes witnessed a pronounced increase (p  .05). As the disease progressed, there was an uptick in midterm activated T lymphocytes (p  .05). Conclusion Subsets of Treg and B‐cells could act as yardsticks for the trajectory of SARS‐CoV‐2 infection and might have potential in forecasting patient trajectories. A comprehensive evaluation of lymphocyte subsets, especially in real‐time, holds the key to discerning the clinical severity in those with COVID‐19. This becomes instrumental in monitoring treatment outcomes, tracking disease evolution, and formulating prognostications. Moreover, the results provide a deeper understanding of the cellular immune defense mechanisms against the novel coronavirus infection

A Tunable Graphene Superlattice with Deformable Periodical Nano-Gating

Graphene superlattices have simple and controllable electronic band structures, which can also be electrostatically tuned. They have been widely studied for band engineering and strong correlated physics, and have led to the discovery of a variety of exciting phenomena. To experimentally study the physics of graphene superlattices in a systematic way, it is desirable to control the structure parameters, which barely exist at the moment, onsite. Here, a tunable superlattice with graphene and a deformable gating structure is demonstrated. The period and duty cycle of the nano-gating, and furthermore of the superlattice potential, can be tuned through altering the shape of the gating structure with piezo-actuators, offering a tunable band structure. The tuning of the electronic band structures of both a two-dimensional and a one-dimensional superlattice is demonstrated with numerical simulations, offering a new approach for tunable electronic and photonic devices

Tunable broadband transmissive terahertz cross-polarization converter enabled by a hybrid metal-graphene metasurface

Graphene has shown potential in terahertz (THz) polarization modulation due to highly tunable optoelectronic properties, fast photoelectric response, and ease of integration. However, the performance of polarization converters based on graphene metasurfaces is often limited by the achievable carrier mobility of large-area graphene. In this paper, a flexible and tunable broadband transmissive THz cross-polarization converter based on a hybrid metal-graphene metasurface is proposed. It is composed of two metal grating layers with a graphene-loaded 45-degree antenna array sandwiched between them. The THz response of the antenna can be tuned by adjusting the graphene Fermi level, which further alters the cross-polarization conversion efficiency (CPCE) of the device. The average CPCE can be continuously tuned from 80.3% to 4.5% within a broadband from 0.6 to 2.0 THz, and the average modulation depth of the whole band is 94.2%. The mechanisms of this highly efficient polarization conversion and dynamic modulation are explained with a transfer matrix method and an equivalent circuit model. Furthermore, the proposed structure has a low requirement on the graphene mobility, which is only 500 cm2/(V·s) here. This work provides a new approach to highly efficient tunable cross-polarization conversion over a broadband in THz, which will promote the application of graphene-based polarization modulators in THz sensing, imaging and communication

Salidroside affects the Th17/Treg cell balance in aplastic anemia via the STAT3/HIF-1α/RORγt pathway

ABSTRACTBackground Acquired aplastic anemia (AA) is a life-threatening disease associated with an imbalance in Th17/Treg cells. Regulating this balance may be an effective treatment approach for AA. Rhodiola rosea has shown efficacy in AA treatment, but its mechanisms remain unclear.Purpose We investigated salidroside's effect (a component of Rhodiola rosea) on Th17/Treg balance in adult AA patients and a mouse model.Methods HIF-1α mRNA and protein levels were measured in AA patients' peripheral blood. Flow cytometry, qRT-PCR, and WB analyzed salidroside's impact on T cell differentiation, Th17 cells, Treg cells, STAT3, HIF-1α, and RORγt expression. ELISA measured hematopoietic growth factors in mouse serum.Results AA patients exhibited elevated HIF-1α levels. Salidroside improved hematopoietic function, increasing blood cell count and enhancing bone marrow. Salidroside induced SCF, TPO, and IL-3 expression while inhibiting IL-2 in mice. Salidroside reduced STAT3, HIF-1α, RORγt, and IL-17a, while increasing FoxP3 expression, correcting the Th17/Treg imbalance in vitro and in vivo.Conclusion Salidroside has potential as a novel AA treatment by correcting the Th17/Treg imbalance through the STAT3/HIF-1α/RORγt pathway