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Despite extensive studies of deposited carbon in Fischer–Tropsch synthesis (FTS), an atomic-level comprehension of the effect of carbon on the morphology of cobalt-based FTS catalysts remains elusive. The adsorption configurations of carbon atoms on different crystal facets of hexagonal close-packed (hcp) Co nanoparticles were studied using density functional theory (DFT) calculations to explore the interaction mechanism between C and Co surfaces. The weaker adsorption strength of C atoms on Co(0001), Co(10-10), and Co(11-20) surfaces accounted for lower diffusion energy, leading to the facile formation of C dimers. Electronic property analysis shows that more electrons are transferred from Co surfaces to C atoms on corrugated facets than on flat facets. The deposition of carbon atoms on Co nanoparticles affects surface energy by forming strong Co-C bonds, which causes the system to reach a more energetically favorable morphology with an increased proportion of exposed Co(10-12) and Co(11-20) areas as the carbon content increases slightly. This transformation in morphology implies that C deposition plays a crucial role in determining the facet proportion and stability of exposed Co surfaces, contributing to the optimization of cobalt-based catalysts with improved performance. [ABSTRACT FROM AUTHOR]

High sensitivity magnetic sensing is proposed using a sandwich structure with polydimethylsiloxane (PDMS) flexible resonator as the core. The directional sensing feature is provided by the sandwich structure's preset magnetic field. The small Young's modulus of flexible material corresponds to larger variation, resulting in a highly sensitive magnetic response. In the unshielded environment, the experimental results demonstrate redshift sensitivity of 1.08 nm / mT and blueshift sensitivity of 1.12 nm / mT, which are attributed to a slight variation in the PDMS's Young's modulus. The directivity curve's concave point has a depth of 34.6 dB. The minimum detectable magnetic field of 0.96 nT · Hz − 1/2 is achieved at 1.4 kHz. [ABSTRACT FROM AUTHOR]

The whispering gallery mode resonator based on a fluoride crystalline material offers the advantage of an ultrahigh quality factor, however, its fast tuning remains a challenge. We propose a tuning method for a CaF2 crystalline resonator using external pressure loading. Through our theoretical calculations and simulations, we discovered that the frequency shift induced by deformation during the pressure tuning of the crystalline resonator is greater than that induced by changes in refractive index. Both shifts were of the same order of magnitude, indicating that both factors must be considered. The experimental results show tuning rates of 1114.6 and 888.2 MHz/MPa in the transverse electric and transverse magnetic modes, respectively. The tuning system can respond to a signal frequency of up to 1.2 MHz. [ABSTRACT FROM AUTHOR]

• Mutations of p53 gene is closely correlated with tumor progression. • Gene therapy can effectively recover tumor suppressor ability of p53. • The change of p53 status substantially enhanced the p53-mediated sensitivity of BTZ. • UCL-guided image facilitated the real-time detection of drug and gene delivery. • The conjunction of H2A enhance biocompatibility and transfection efficiency. The design and development of advanced gene/drug codelivery nanocarrier with good biocompatibility for cancer gene therapy is desirable. Herein, we reported a gene delivery nanoplatform to synergized bortezomib (BTZ) for cancer treatment with histone H2A-hybrided, upconversion luminescence (UCL)-guided mesoporous silica nanoparticles [UCNPs(BTZ)@mSiO 2 -H2A]. The functionalization of H2A on the surface of UCNPs(BTZ)@mSiO 2 nanoparticles realized the improvement of biocompatibility and enhancement of gene encapsulation and transfection efficiency. More importantly, then UCNPs(BTZ)@mSiO 2 -H2A/p53 induced specific and efficient apoptotic cell death in p53-null cancer cells and restored the functional activity of tumor suppressor p53 by the success of co-delivery of BTZ/p53. Moreover, the transfection with UCNPs(BTZ)@mSiO 2 -H2A/p53 in p53-deficient non-small cell lung cancer cells changed the status of p53 and substantially enhanced the p53-mediated sensitivity of encapsulated BTZ inside the UCNPs(BTZ)@mSiO 2 /p53. Meanwhile, core-shell structured mesoporous silica nanoparticles UCNPs@mSiO 2 as an UCL agent can detect the real-time interaction of nanoparticles with cells and uptake/penetration processes. The results here suggested that the as-developed UCNPs(BTZ)@mSiO 2 -H2A/p53 nanoplatform with coordinating biocompatibility, UCL image, and sustained release manner might be desirable gene/drug codelivery nanocarrier for clinical cancer therapy. [ABSTRACT FROM AUTHOR]

A self-consistent all-pathway quantum dot (QD) rate equation model, in which all possible relaxation pathways are considered, is used to investigate the influence of quality ( Q ) factor on the carrier dynamics of 1.3-μm InAs/GaAs QD photonic crystal (PhC) nanolasers. It is found that Q factor not only affects the photon lifetime, but also modulates the carrier occupation in QDs. About three times increases of carrier injection efficiency in QD ground state can be realized in nanocavity with high Q factor. However, it also reveals that over 90% improvement of threshold current happens when Q factor increases from 2000 to 7000, which means it might be not necessary to pursuit for ultrahigh Q factor for the purpose of low threshold current. [ABSTRACT FROM AUTHOR]

The tumor suppressor p53 serves important roles in cell cycle arrest and apoptosis, and its activation increases the sensitivity of cancer cells to radiotherapy or chemotherapy. In the present study, the small molecule 2-[1-(4-(benzyloxy)phenyl)-3-oxoisoindolin-2-yl)-2-(4-methoxyphenyl)] acetic acid (CDS-3078) significantly increased p53 mRNA expression levels in a dose-dependent manner. Treatment with CDS-3078 increased p53 expression levels and p53-mediated activation of its downstream target genes in HeLa cells. Additionally, p53+/+ HeLa cells treated with CDS-3078 presented with dysfunctional mitochondria, as indicated by the decrease in Bcl-2 levels, the increase in Bcl-2 homologous antagonist killer and the increase in cytochrome c release from the mitochondria to the cytoplasm. The present results suggested that CDS-3078 treatment significantly induced G2/M phase cell cycle arrest. Therefore, CDS-3078 administration induced apoptosis via p53-mediated cell cycle arrest, causing mitochondrial dysfunction and resulting in apoptotic cell death in cervical cancer cells. Collectively, the present results suggested that CDS-3078 may be a potential anticancer agent. [ABSTRACT FROM AUTHOR]