Search

Ambient fine particulate matter (PM2.5), a vital environmental toxicant, not only adversely affects the cardiovascular and respiratory systems but also potentially exhibits an association with intestinal inflammation and colorectal cancer (CRC). The underlying molecular mechanisms of PM2.5 impacts on CRC are still unclear. In this study, we utilized collected ambient PM2.5 and standard reference material SRM2786 to investigate the toxic effects on the colon through in vivo chronic exposure mouse and in vitro cell culture models. We employed a chronic mouse exposure model to clarify the colonic injury and gut microbiome biomarkers. Prolonged exposure to PM2.5 via oropharyngeal aspiration led to a significant rise in colonic epithelial proliferation and reduced colon length in mice. It triggered characteristics indicative of gut microbiota dysbiosis linked to inflammatory bowel disease. The gut microbiome alternations may serve as a biomarker indicating the colonic health impacts of PM2.5 exposure. PM2.5 and SRM2786-induced cytotoxicity manifested as autophagy dysregulation-mediated abnormal proliferation, IL-8 production, p62/SQSTM1 accumulation, and lysosomal membrane damage in human colon cells WiDr and Caco-2. Both PM2.5 and SRM2786 exposures led to the accumulation of p62/SQSTM1 and compromised lysosomal membrane integrity, showing impaired autophagic flux in WiDr and Caco-2 cells. Finally, we examined the correlations between atmospheric PM2.5 data and biomarkers of colonic inflammation in human population. The serum level of IL-8 was significantly correlated with regional anthropogenic pollutants. In conclusion, our findings elucidate that ambient PM2.5 exhibits adverse effects on colon health manifested as inflammation, aberrant proliferation, and gut dysbiosis, potentially mediated through autophagy dysregulation, thereby highlighting the importance of further research on the impact of environmental pollutants on gastrointestinal health.

Abstract Artificial nanofluidic networks are emerging systems for blue energy conversion that leverages surface charge‐derived permselectivity to induce voltage from diffusive ion transport under salinity difference. Here the pivotal significance of electrostatic inter‐channel couplings in multi‐nanopore membranes, which impose constraints on porosity and subsequently influence the generation of large osmotic power outputs, is illustrated. Constructive interference is observed between two 20 nm nanopores of 30 nm spacing that renders enhanced permselectivity to osmotic power output via the recovered electroneutrality. On contrary, the interference is revealed as destructive in two‐dimensional arrays causing significant deteriorations of the ion selectivity even for the nanopores sparsely distributed at an order of magnitude larger spacing than the Dukhin length. Most importantly, a scaling law is provided for deducing the maximal membrane area and porosity to avoid the selectivity loss via the inter‐pore electrostatic coupling. As the electric crosstalk is inevitable in any fluidic network, the present findings can be a useful guide to design nanoporous membranes for scalable osmotic power generations.

A pregnancy booster dose significantly reduces the risk and severity of COVID-19, and it is widely recommended. A prospective cohort study was conducted to compare the transplacental passage of maternal antibodies from vaccination or infection during three trimesters against both the vaccine-targeted Wuhan strain and the Omicron strain of SARS-CoV-2. Maternal–infant dyads from vaccinated mothers were collected between 6 June 2022 and 20 September 2022. We analyzed 38 maternal–infant dyads from mothers who had been infected with COVID-19 and 37 from mothers without any previous infection. Pregnant women who received their last COVID-19 vaccine dose in the third trimester exhibited the highest anti-spike protein antibody levels and neutralizing potency against both the Wuhan strain and Omicron BA.2 variant in their maternal and cord plasma. Both second- and third-trimester vaccination could lead to a higher level of neutralization against the Wuhan and Omicron strains. COVID-19 infection had a negative effect on the transplacental transfer ratio of SARS-CoV-2 antibodies. A booster dose during the second or third trimester is encouraged for the maximum transplacental transfer of humoral protection against COVID-19 for infants.

Boiling heat transfer is the basis of many commonly used cooling techniques. In cooling of electronic devices, for example, it is desirable to further miniaturize heat exchangers to achieve higher heat transfer, and thus it is necessary to understand boiling phenomena on shorter spatial and temporal scales. This is especially challenging at the nanometer scale because conventional imaging techniques cannot capture the dynamics of nanobubbles, owing to the Abbe diffraction limit. Here in this research, we utilize the nanopore Joule heating system that enables the generation of nanobubbles and simultaneous diagnosis of their nanosecond resolution dynamics using resistive pulse sensing. When a bias voltage is applied across a silicon nitride nanopore immersed in an aqueous salt solution, Joule heat is generated owing to the flow of ionic current. With increasing voltage, the Joule heating intensifies, and the temperature and entropy production in the pore increase. Our sensing results show that nanopore boiling follows the theory of minimum entropy production and attempts to settle to a minimum dissipative state. This results in two boiling bifurcations corresponding to the transition between different boiling states. These characteristics of nanopore boiling are represented by an M-shaped boiling curve, experimentally obtained from the Joule heat variation with the applied voltage. A theoretical framework is proposed to model the thermodynamics of nanopore bubbles and estimates the system dissipation, which explains the four arms of the M-shaped boiling curve. The present study reveals that the utilization of nanopore boiling as a benchmark platform offers a valuable means for investigating the intricate boiling phenomenon and its correlation with nanoscale bubble dynamics. This would provide much-needed fundamental insights into the chaotic transition boiling regime, which is least understood.

Nonlocal effects originating from interactions between neighboring meta-atoms introduce additional degrees of freedom for peculiar characteristics of metadevices, such as enhancement, selectivity, and spatial modulation. However, they are generally difficult to manipulate because of the collective responses of multiple meta-atoms. Here, we experimentally demonstrate the nonlocal metasurface to realize the spatial modulation of dark-field emission. Plasmonic asymmetric split rings (ASRs) are designed to simultaneously excite local dipole resonance and nonlocal quasi-bound states in the continuum and spatially extended modes. With one type of unit, nonlocal effects are tailored by varying array periods. ASRs at the metasurface's edge lack sufficient interactions, resulting in stronger dark-field scattering and thus edge emission properties of the metasurface. Pixel-level spatial control is demonstrated by simply erasing some units, providing more flexibility than conventional local metasurfaces. This work paves the way for manipulating nonlocal effects and facilitates applications in optical trapping and sorting at the nanoscale. [ABSTRACT FROM AUTHOR]

In this study, the newly synthesized polyaniline (PANI)/polyethylenimine modified nitrogen doped graphene quantum dot (PN-GQD)/tungsten oxide (WO3) ternary composites were used as ammonia (NH3) gas sensor detected the NH3 at room temperature. Fourier transform infrared spectrometer, fieldemission scanning electron microscopy, transmission electron microscopy, and x-ray photoelectron spectroscopy were applied to illustrate the chemical structure and morphology of the fabricated ternary composites. The NH3 gassensing performances of PANI/PN-GQD/WO3 composite sensor were determined in the concentration between 0.6 and 2.0 ppm at room temperature and the response value of the ternary composite sensor with an exposure of 1.0 ppm NH3 was 19.9, which was much better than those of PANI and PANI/WO3 sensors. Because their highly sensitive detection of NH3 ranging from the concentration between 0.6 and 2.0 ppm at room temperature, the PANI/PNGQD/WO3 composite sensor was confirmed to be extremely effective to detect the kidney or hepatic disease from the human breath. This ternary composite sensor with an exposure of 1.0 and 2.0 ppm NH3 also displayed extraordinary repeatability and selectivity at room temperature. According to these findings, this fabricated PANI/PN-GQD/WO3 composite sensor will be an excellent gassensing material to detect the kidney or hepatic disease from the human breath. [ABSTRACT FROM AUTHOR]