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Impact of memory T cells on SARS-CoV-2 vaccine response in hematopoietic stem cell transplant
During the COVID-19 pandemic, hematopoietic stem cell transplant (HSCT) recipients had elevated mortality rates from SARS-CoV-2 infection, ranging between 10–40%. SARS-CoV-2 mRNA vaccines are important tools in preventing severe disease, yet their efficacy post-transplant remains unclear, especially in patients subjected to myeloablative chemotherapy and immunosuppression. We evaluated humoral and adaptive immune responses to the SARS-CoV-2 mRNA vaccination series in 42 HSCT recipients and 5 healthy controls. Post-vaccination responses were assessed by anti-spike IgG and nucleocapsid levels, and antigen specific T cell activity. Immune profiling was performed using clinical flow and mass cytometry. Patients were selected based on humoral and cellular responses for single-cell RNA with TCR and BCR sequencing. Our studies revealed defects in memory T cells that correlated with an absence of cellular response despite nearly universal humoral response. Several patients with a robust antibody response developed COVID-19 infection, but none developed severe disease or died from the infection.
Regional analysis of APOE polymorphism in Alzheimer’s disease in Spain
Abstract Alzheimer’s disease (AD) is a progressive neurodegenerative disorder with significant cognitive and functional impacts. Genetic factors, particularly the APOE gene and its allelic variants (ε2, ε3, ε4), play a critical role in AD susceptibility. This study analyzed the allelic frequency and distribution of APOE polymorphisms in three provinces of Castilla y León (León, Soria, Salamanca), Spain, to explore their potential relationship with AD risk. Genotypes were determined using polymerase chain reactions, and statistical analyses revealed significant regional variations. The ε3/ε3 genotype was the most prevalent overall, while the ε3/ε4 genotype predominated in specific areas like Ponferrada. The absence of homozygous ε4 individuals in Soria contrasts sharply with higher frequencies in Salamanca. These differences suggest historical and migratory influences on genetic variability. Identifying regional genetic patterns enhances our understanding of AD risk and supports the development of targeted preventive strategies. Early detection of high-risk alleles could improve patient outcomes, reduce healthcare burdens and inform public health policies.
Novel rare-earth doped Cs2NaGdCl6:Sb3+ double perovskite nanocrystals toward good ability of color tuning with high quantum efficiency
All-inorganic halide double perovskites have attracted extensive attention as new luminescent materials owing to their high luminous efficiency and wide emission spectrum. In this work, blue-red bicolor Cs2NaGdCl6 (CNGC) double perovskite nanocrystals doped with Sb3+/Ho3+ were prepared using a hydrothermal method. The incorporation of Sb3+ significantly enhanced the intrinsic “self-trapped excitons (STEs)” with a wide-band bright blue emission centered at 470 nm. On this basis, different concentrations of Ho3+ were introduced to achieve color tunable emission from blue to red region, with extremely high quantum efficiencies of 96.53% and 92.17%, respectively. By the use of diverse methods, including spectroscopic analysis and fluorescence lifetime, the mechanism of efficient luminescence related to the different dopant concentrations was comprehensively explored. Results show that Sb3+ not only can enhance the intrinsic STEs luminescence of the CNGC but also has an efficient activation effect on the rare earth ion Ho3+, because it plays the role as a bridge for the two energy transfer channels between the luminescence centers, and the details of the mechanism and energy transfer efficiency were investigated. Thermal stabilities of the double perovskites were studied over the temperature range of 303–473 K and good performances were demonstrated from the fact that the PL intensities of CNGC:1%Sb3+ and CNGC:1%Sb3+/10%Ho3+ at 423 K were 75.1% and 70.1% compared to those at 303 K, respectively. With the CNGC:1%Sb3+ and CNGC:1%Sb3+/10Ho3+ used, the UV light-emitting diode activated devices were fabricated and characterized. The bright blue and red emissions suggest the materials’ prominent potential in the application of plant lighting. Finally, to achieve white-light emission in the sole CNGC matrix, a strategy of tri-doping Tb3+ was proposed based on the principle of the three primary colors. The device fabrication with CNGC:1%Sb3+/10%Ho3+/2.5%Tb3+ sample and the characterization processes prove its high feasibility and then provide valuable insights in the design of Sb ion-doped lead-free double perovskites toward easily tunable color in a wide range which can be applied in various fields.
Executives’ IT background and corporate digital technology innovation: Evidence from Chinese microenterprises
This study examines how executives’ IT backgrounds affect corporate digital technology innovation, using panel data from listed companies between 2011 and 2021. Findings indicate that executives’ IT backgrounds significantly enhance corporate digital technology innovation, particularly in digital technology invention patents, where the effect is especially pronounced, and the results are robust. Mechanistic analysis suggests managerial myopia and executives’ attention to digital technology are key factors that allow executives’ IT backgrounds to promote corporate digital technology innovation. Further analysis shows executives’ IT backgrounds have a greater promotional effect on digital technology innovation in state-owned enterprises, non-IT sectors, firms with influential executives, and organizations with long-serving executives. Economic analysis reveals that executives’ IT backgrounds can improve corporate financial performance by enhancing digital technology innovation. This paper highlights the importance of executive IT human capital and provides insights into government and corporate talent recruitment policies.
Effect of environmental factors on laccase-mediated 17β-estradiol coupling reaction
Dynamical signature of the onset of sol-gel phase transition in aqueous solutions of hydrophobically modified poly(acrylic acid)-based copolymers
Sol-gel transition-driven relaxation dynamics of aqueous solutions of rationally designed polyacrylic acid (PAA)-based copolymers with hydrophobic modifications were explored by employing time-resolved fluorescence and MHz–GHz dielectric relaxation (DR) measurements. This sol-gel transition driven dynamics was monitored over an incubation period of 30 days, as these systems were found to undergo gelation after a few weeks. The designed PAA-based homo (P0), hydrophobically modified (∼4%) copolymers (P4, P6), and their coumarin 343 (C343) attached analogous copolymers (P4′, P6′) were synthesized by reversible addition–fragmentation chain transfer polymerization and characterized by 1H NMR spectroscopy and size exclusion chromatography (SEC). Dynamic light scattering experiments of aqueous copolymer solutions showed a gradual increment of hydrodynamic diameter (Dh) up to ∼4000 nm, and the onset of sol-gel transition was estimated by locating the intersection of two distinct slopes produced by the plots of average Dh as a function of incubation time. The sol-gel transition for these copolymer solutions (aqueous) was clearly demonstrated by the progressive slowing down of DR times and the rotational fluorescence anisotropy times tracked over the entire incubation period. Interestingly, the onset time for the sol-gel transition was found to be insensitive to the chemical binding of the fluorescent probe to these polymers. A comparison between the steady state UV–VIS absorption and fluorescence spectral characteristics of aqueous solutions of these copolymers with chemically bound and externally added C343 suggested that the sol-gel transition involved polymer aggregation. This study may be useful for designing supramolecular polymer gels for biomedical applications.
The agreement of the various distance walkway in the 6-minute walk test in healthy adults
Background Despite a practical guideline of 30-meter walking path during 6-minute walk test (6MWT), such walking course length is not possible in every clinical setting due to unavailable sufficient space. Existing evidence has investigated using several shorter course lengths, it remains unclear whether a walking course length shorter than the standard walking course length is appropriate for 6MWD testing. This study aimed (i) to compare maximum walking distances at various shorter walking course lengths (i.e., 10, 20, and 25 meters) and 30 meters, and (ii) to assess agreements in maximum walking distances achieved at intervals below 30 meters, specifically 10, 15, 20, and 25 meters. Methods This study was a cross-sectional with cross-over design. Forty-eight healthy participants were randomly ordered to perform 6MWT with five different walkways (10, 15, 20, 25, 30 meters). The maximum walking distance (six-minute walk distance, 6MWD) covered was recorded. Results Eligible participants aged 41.0 ± 17.2 years, with equal sex (24 males) participated in this study. The 6MWD at 10, 15, and 20-meter walkways significantly shorter than the 30-meter standard walkway (489.6 ± 59.3 m, 513.1 ± 62.6 m, 524.7 ± 63.7 m vs 539.1 ± 63.1 m, respectively (P<0.01)). Very strong agreement was observed at 15, 20, and 25 meters with the standard 30 meters (0.819–0.875, P<0.001). Subgroup analysis showed strong to very strong agreement in 10-meter walkway length onwards with the standard walkway length among older adults (0.757–0.918, P<0.001). Conclusions Testing on 20 meters walkway and shorter yielded varied results compared to the standard 30-meter walk, with exceptional congruence observed at 15 meters onwards. In particular, a minimum walkway of 10 meters had strong agreement with a standard 30-meter walkway in elderly.
Quantization of nonequilibrium heat transport models based on isomorphism and gauge symmetry
Abstract The diffusive model in a local thermal equilibrium medium has been well established for classical heat transport. In this study, we investigated the gauge potential formulation of a heat transfer model in a non equilibrium system within classical and quantum frameworks. To achieve this, scalar and vector potential and gauge functions were first introduced to characterize the heat transport model. Subsequently, minimal coupling of the heat potential was established via isomorphic mapping between the heat transport and electromagnetism. The Schrödinger equation with quantized heat potentials that fulfill the gauge symmetry is established. Based upon, we further studied the quantization of enthalpy and entropy from a reversible thermodynamic process, including continuous and discretized system. Later, the connections between the non-isentropic condition and gauge symmetry violation were revealed to categorize classical-permitted and quantum-permitted processes. To support the study, thermal quantities are calculated according to the recent report in literature for the two predicted heat transport modes. Theoretically, it has been shown that the quantization of heat potentials as a consequence of isomorphic characterization and gauge symmetry. By incorporating the critical temperature and local symmetry breaking, it interprets the transition of quantum formulation to classical formulation in finite spatial and temporal limits.
Breakdown of broken-symmetry approach to exchange interaction
Broken-symmetry (BS) approaches are widely employed to evaluate Heisenberg exchange parameters, primarily in combination with DFT calculations. For many magnetic materials, BS-DFT calculations give reasonable estimations of exchange parameters, although systematic failures have also been reported. While the latter were attributed to deficiencies of approximate exchange–correlation functional, we prove here by treating a simple model system that the broken-symmetry methodology has serious problems. Detailed analysis clarifies the intrinsic issue with the broken-symmetry treatment of low-spin states. It shows, in particular, that the error in the BS calculation of exchange parameter scales with the degree of covalency between the magnetic and the bridging orbitals. This is due to the constraint on the form of multiconfigurational state imposed by the BS determinant, a feature common to other single-reference methods too. As a possible tool to overcome this intrinsic drawback of single-determinant BS approaches, we propose their extension to a minimal multiconfigurational version.
A randomized controlled trial of nasal airway ventilation technique in edentulous patients during anesthesia induction
Micromechanism study on dielectric properties of natural ester insulating oil modified by liquid crystal based on molecular dynamics
Natural ester (NE) insulating oil is increasingly recognized as an ideal insulating medium for power equipment, attributed to its high ignition point and biodegradability. As power systems advance to higher voltage levels, enhancing the dielectric properties of natural ester insulating oil has emerged as a key research focus. While nanoparticles enhance dielectric properties, their limited dispersion stability restricts practical applications. Liquid crystals, a novel functional modification material compatible with insulating oil, provide a new approach for modifying NE due to their unique mobility and anisotropy. Experimental results indicate that incorporating liquid crystal molecules at a 0.3% mass fraction enhances the AC breakdown strength of natural ester insulating oil by 16.7%. By combining molecular dynamics and density functional theory principles, the microscopic mechanism of liquid crystal modification was analyzed by modeling oil molecules before and after modification. The study found that liquid crystal molecules significantly reduce the system’s free volume and hinder water molecule diffusion through hydrogen bonding. Furthermore, the high electron affinity of liquid crystal molecules reduces carrier mobility by capturing free electrons, thereby effectively suppressing partial discharges and electrochemical reactions. This study investigates the modification mechanism of a novel functional material on the dielectric properties of natural ester insulating oil from a microscopic perspective.