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Physical Vapor Deposition (PVD) of Tantalum/Tantalum Nitride (Ta/TaN) liner and barrier plays a crucial role in the copper-interconnecting part of semiconductor manufacturing, and this is used for the 130 nm–5nm technology node and beyond. This study focuses on the surface preparation and characterization of wire-arc spray directed energy deposition (DED) coating in the refurbishment process of PVD chamber kits. Spray coating adhesion strength is enhanced due to the pretreatment of the substrate with grit blasting, which creates a suitable surface texture, and the replacement of aluminum alloy as wire-arc spray DED coating material from pure aluminum (99.8%). However, it was experimentally found that using high adhesion strength coating chamber kits increases the probability of out-of-control (OOC) occurrences in the mid-stage of the kit lifetime, and the fundamental reasons may be attributed to the spiky surface morphology of wire-arc spray DED coating layers. Finite element analysis simulates stress distribution and identifies stress concentration regions within the multilayer Ta/TaN thin film using two surface morphologies with significantly different curvature radii of spray coatings. Differences in wire-arc spray DED processing parameters include a slower travel speed, a longer spray time, and a lower feed rate. It is numerically simulated and experimentally observed that coating surface morphology dramatically affects thin film delamination, which is the primary cause of particle defects. This study emphasizes the potential mechanisms for forming particle defects, improved uniformity in spray coatings, and increased surface curvature radius to minimize stress concentration.

Background: Protection against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection relies on immunity generated after primary infection. However, humoral immunity following primary infection with the Omicron variant is not well understood. Methods: We prospectively recruited children

Background: Occupational workers at altitudes are more prone to falls, leading to catastrophic outcomes. Acrophobia, height-related anxiety, and affected executive functions lead to postural instabilities, causing falls. This study investigated the effects of repeated virtual height exposure and training on cognitive processing and height-related anxiety. Methods: Twenty-eight healthy volunteers (age 20.48 ± 1.26 years; mass 69.52 ± 13.78 kg) were recruited and tested in seven virtual environments (VE) [ground (G), 2-story altitude (A1), 2-story edge (E1), 4-story altitude (A2), 4-story edge (E2), 6-story altitude (A3), and 6-story edge (E3)] over three days. At each VE, participants identified occupational hazards present in the VE and completed an Attitude Towards Heights Questionnaire (ATHQ) and a modified State-Trait Anxiety Inventory Questionnaire (mSTAIQ). The number of hazards identified and the ATHQ and mSTAIQ scores were analyzed using a 7 (VE; G, A1, A2, A3, E1, E2, E3) x 3 (DAY; DAY 1, DAY 2, DAY 3) factorial repeated measures analysis of variance. Results: The participants identified the lowest number of hazards at A3 and E3 VEs and on DAY 1 compared to other VEs and DAYs. ATHQ scores were lowest at G, A1, and E1 VEs. Conclusion: Cognitive processing is negatively affected by virtual altitudes, while it improves with short-term training. The features of virtual reality, such as higher involvement, engagement, and reliability, make it a better training tool to be considered in ergonomic settings. The findings of this study will provide insights into cognitive dual-tasking at altitude and its challenges, which will aid in minimizing occupational falls.

Background/Purpose: The aims of this study were to determine the long-term associated factors for chronic kidney disease (CKD) progression in a pediatric group with non-glomerular (non-GN) etiologies. Methods: Pediatric patients with a presumptive diagnosis of CKD were enrolled to this study. Recorded information included demographic and laboratory information. We included the patients with non-GN etiologies and investigated the factors including systolic and diastolic blood pressure (BP), proteinuria, and anemia status in association with reductions in the estimated glomerular filtration rate (eGFR). Results: A total of 308 children were enrolled and the mean duration of follow-up was 4.40 ± 3.53 years. Median baseline age was 5 years old and the males represented 55% of all patients. One-unit increased baseline systolic BP z-score was associated with 1.2 ml/min per 1.73 m2 (95% CI = −2 to −0.5) faster rate of eGFR decline. The presence of baseline proteinuria and anemia were also associated with 4.1 ml/min per 1.73 m2 (95% CI = −5.7 to −2.5) and 2.2 ml/min per 1.73 m2 (95% CI = −3.6 to −0.8) more rapid eGFR declination, respectively. Hypertension, anemia and proteinuria during the follow-up were also associated with 3.25 ml/min per 1.73 m2 (95% CI = −5.32 to −1.18), 4.34 ml/min per 1.73 m2 (95% CI = −7.25 to −1.43) and 4.97 ml/min per 1.73 m2 (95% CI = −8.23 to −1.71) more rapid eGFR declination, respectively. Conclusion: Elevated systolic BP, proteinuria, and anemia are independently associated with CKD progression in pediatric patients with non-GN etiologies. Keywords: Chronic kidney disease, Progression, Children, Congenital anomalies of the kidney and the urinary tract

We combined carbon dioxide (CO2)-responsive cytosine-containing rhodamine 6G (Cy-R6G) as a hydrophobic anticancer agent with hydrogen-bonded cytosine-functionalized polyethylene glycol (Cy-PEG) as a hydrophilic supramolecular carrier to construct a CO2-responsive drug delivery system, with the aim of enhancing the responsiveness of the system to the tumor microenvironment and thus the overall effectiveness of anticancer therapy. Due to self-complementary hydrogen bonding interactions between cytosine units, Cy-R6G and Cy-PEG co-assemble in water to form spherical-like nanogels, with Cy-R6G effectively encapsulated within the nanogels. The nanogels exhibit several distinctive physical features, such as widely tunable nanogel size and drug loading capacity for Cy-R6G, intriguing fluorescence properties, high co-assembled structural stability in normal aqueous environments, enhanced anti-hemolytic characteristics, sensitive dual CO2/pH-responsive behavior, and precise and easily controllable CO2-induced release of Cy-R6G. Cytotoxicity assays clearly indicated that, due to the presence of cytosine receptors on the surface of cancer cells, Cy-R6G-loaded nanogels exert selective cytotoxicity against cancer cells in pristine culture medium, but do not affect the viability of normal cells. Surprisingly, in CO2-rich culture medium, Cy-R6G-loaded nanogels exhibit a further significant enhancement in cytotoxicity against cancer cells, and remain non-cytotoxic to normal cells. More importantly, a series of in vitro experiments demonstrated that compared to pristine culture medium, CO2-rich culture medium promotes more rapid selective internalization of Cy-R6G-loaded nanogels into cancer cells through cytosine-mediated macropinocytosis and thus accelerates the induction of apoptosis. Therefore, this newly developed system provides novel avenues for the development of highly effective CO2-responsive drug delivery systems with potent anticancer capabilities.

We report important progress in the preparation and development of gas-responsive fluorescent materials with potential as efficient anticancer treatments and fluorescent probes for biomedical imaging. An environmental stimuli-responsive multifunctional material (ESMM) composed of rhodamine 6 G containing a pH-sensitive spirolactam unit and a self-complementary multiple hydrogen-bonded adenine group was successfully synthesized through a simple and efficient two-step synthetic pathway. ESMM has extremely poor water solubility, even in a weakly acidic aqueous environment, but can easily dissolve in common organic solvents. Due to the unique polar heteroaromatic structure of the adenine group that confers chemical reactivity (or responsiveness) with CO2, hydrophobic ESMM can rapidly and completely dissolve in water on simple CO2 bubbling treatment, which is followed by formation of self-assembled spherical-like nanoparticles. The resulting nanoparticles demonstrate unique spontaneous fluorescent characteristics in water and their photophysical properties, surface charge, acid-base characteristics, and self-assembled morphology can be quickly and stably switched on and off by alternating cycles of CO2 and N2 bubbling, to thus effectively manipulate their physical performance. Importantly, in vitro cell assays clearly indicated that protonation of the adenine group by CO2 remarkably enhances the anti-hemolytic properties of ESMM and results in highly potent and selective cytotoxicity against cancer cells at low doses, but not in normal cells. In contrast, pristine ESMM did not exhibit selective cytotoxic effect on normal or cancer cells. Therefore, this newly discovered CO2-responsive system may have a great potential to improve the safety and effectiveness of chemotherapeutic drugs.

We developed a carbon dioxide (CO2)-responsive supramolecular drug carrier system through a combination of hydrophobic CO2-sensitive imidazole-containing rhodamine 6G (I–R6G) as an efficient anticancer agent and hydrophilic ureido-cytosine (UrCy) end-capped polyethylene glycol (UrCy-PEG) as a self-assembled nanocarrier that could potentially enhance the safety and efficiency of cancer treatment. Owing to the self-complementary quadruple hydrogen bonding interactions between the UrCy moieties at the polymer chain ends, UrCy-PEG can spontaneously self-assemble into spherical-like nanoobjects in water that can effectively encapsulate hydrophobic I–R6G and form co-assembled nanoparticles with tunable sizes (depending on the I–R6G loading content). These nanoparticles display several notable physical features, including high structural stability in normal physiological aqueous media or red blood cell-containing media, unique CO2-responsiveness, and controlled CO2-sensitive I–R6G release. In vitro cytotoxicity assays clearly indicated I–R6G-loaded nanoparticles exerted selective cytotoxicity towards cancer cells, but had no adverse effects on normal cells. I–R6G-loaded nanoparticles exerted significantly higher levels of cytotoxicity at lower doses in CO2-treated cell culture media compared to I–R6G-loaded nanoparticles in pristine media. More importantly, cellular assays demonstrated that—in comparison to I–R6G-loaded nanoparticles in pristine media—CO2-treated culture media accelerated macropinocytic internalization of I–R6G-loaded nanoparticles into cancer cells, and subsequently led to more rapid induction of apoptosis in cancer cells and massive programmed cell death. Thus, this newly created system may act as a potential route to manipulate the drug delivery and release performance of self-assembled nanobjects for efficient cancer therapy.

Stripe arrays of poly(methacrylic acid) (PMAA) brushes were grafted using a photoresist template to fabricate one-dimensional photonic crystal (OPCs). The as-prepared samples were first bound with protein G to immobilize and orient tails of the antibody of Pa (abY). A fluidic diffraction chip based on the abY-tailed PMMA OPC was fabricated to examine the ability of Pa detection from whole blood specimen. Pa was attached to the abY-tailed PMMA OPC after flowing through the fluidic chip, which changed the diffraction intensity. A laser beam was employed to analyze the reflective signals of OPCs at an incident angle of 45°. The abY-tailed PMAA OPC possessed an optical feature with a characteristic diffraction effect such that the projection of the laser beam on the plane of the OPC chip was parallel to the strips in SII configurations, whereas they were perpendicular in ST configurations. The degree of the diffraction intensity exhibited a linear response to Pa at concentrations from 102 to 107 CFU mL−1, and the limit of detection was 100 CFU mL−1, indicating the excellent sensitivity in Pa-spiked whole blood samples. The proposed platform provides a rapid, label-free method for Pa detection to improve the administration of antibiotics in a timely manner.