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Concerns regarding air pollution and the risk of infectious diseases caused by bioaerosols have led to growing demand for effective filtration solutions. The effective capture of bioaerosols is essential; however, addressing the potential multiplication of captured aerosols on the air filter over time is also crucial. Therefore, the development of air filters with enhanced antimicrobial protection is imperative for preventing the proliferation of bioaerosols and ensuring safer and healthier air filtration systems. In this study, antimicrobial peptides conjugated nanostructures were used to enhance the capture and killing of bioaerosols with synergistic chemo-mechano-antimicrobial actions. We designed a puncturable nanostructure on an air filter and functionalized it with the antimicrobial LL-37 peptide. Bioaerosol filtration and antimicrobial performance tests were conducted to evaluate the synergistic effects of the antimicrobial puncturable nanostructures on bioaerosol removal. The peptide-conjugated puncturable nanostructured air filter outperformed bare air filters in bioaerosol capture and exhibited significantly better contact-killing properties against bioaerosols. These attributes indicate the ability of the filter to significant capture and kill airborne pathogens. The synergetic chemo-mechano-antimicrobial nanostructured filter is promising for combating airborne threats and serves as a safe filtration solution that is free from biotoxicity concerns and is suitable for widespread implementation in the market. [ABSTRACT FROM AUTHOR]

Photocatalysis is a promising technique due to its capacity to efficiently harvest solar energy and its potential to address the global energy crisis. However, the structure–activity relationships of photocatalyst during wavelength-dependent photocatalytic reactions remains largely unexplored because it is difficult to measure under operating conditions. Here we show the photocatalytic strain evolution of a single Au nanoparticle (AuNP) supported on a TiO2 film by combining three-dimensional (3D) Bragg coherent X-ray diffraction imaging with an external light source. The wavelength-dependent generation of reactive oxygen species (ROS) has significant effects on the structural deformation of the AuNP, leading to its strain evolution. Density functional theory (DFT) calculations are employed to rationalize the induced strain caused by the adsorption of ROS on the AuNP surface. These observations provide insights of how the photocatalytic activity impacts on the structural deformation of AuNP, contributing to the general understanding of the atomic-level catalytic adsorption process. The wavelength-dependent structural deformations of nanoparticles during photocatalysis are poorly understood. Here, the authors present the photocatalytic strain evolution of a single Au nanoparticle using 3D Bragg coherent X-ray diffraction imaging. [ABSTRACT FROM AUTHOR]

Efficient pathogen enrichment and nucleic acid isolation are critical for accurate and sensitive diagnosis of infectious diseases, especially those with low pathogen levels. Our study introduces a biporous silica nanofilms-embedded sample preparation chip for pathogen and nucleic acid enrichment/isolation. This chip features unique biporous nanostructures comprising large and small pore layers. Computational simulations confirm that these nanostructures enhance the surface area and promote the formation of nanovortex, resulting in improved capture efficiency. Notably, the chip demonstrates a 100-fold lower limit of detection compared to conventional methods used for nucleic acid detection. Clinical validations using patient samples corroborate the superior sensitivity of the chip when combined with the luminescence resonance energy transfer assay. The enhanced sample preparation efficiency of the chip, along with the facile and straightforward synthesis of the biporous nanostructures, offers a promising solution for polymer chain reaction-free detection of nucleic acids. Efficient enrichment and isolation of pathogens are crucial for accurate and sensitive disease identification. Here, the authors present a chip equipped with biporous nanofilms that induces a nanovetex in a microfluidic channel for nucleic acid enrichment, isolation, and detection. [ABSTRACT FROM AUTHOR]

Owing to the strong absorption of water in the near-infrared (NIR) region near 1.0 μm, this wavelength is considered unsuitable as an imaging and analytical signal in biological environments. However, 1.0 μm NIR can be converted into heat and used as a local water-molecular heating strategy for the photothermal therapy of biological tissues. Herein, we describe a Nd-Yb co-doped nanomaterial (water-heating nanoparticles (NPs)) as strong 1.0 μm emissive NPs to target the absorption band of water. Furthermore, introducing Tm ions into the water-heating NPs improve the NIR lifetime, enabling the development of a NIR imaging-guided water-heating probe (water-heating NIR NPs). In the glioblastoma multiforme male mouse model, tumor-targeted water-heating NIR NPs reduce the tumor volume by 78.9% in the presence of high-resolution intracranial NIR long-lifetime imaging. Hence, water-heating NIR NPs can be used as a promising nanomaterial for imaging and photothermal ablation in deep-tissue-bearing tumor therapy. Neodymium (Nd)-doped nanoparticles have been described for imaging-guided photothermal therapy. Here the authors design a Nd-Yb co-doped nanomaterial as nearinfrared long-lifetime imaging-guided waterheating probe, showing photothermal ablation in a glioblastoma pre-clinical mode [ABSTRACT FROM AUTHOR]

Lanthanide-doped upconversion nanomaterials are well known for converting near-infrared (NIR) excitation photons into visible, ultraviolet, and NIR emission photons. Excitation of NIR light offers low autofluorescence background and high penetration depth in biological environments due to the reduced light scattering. Consequently, these have attracted considerable interest because their exceptional optical properties have led to applications in diverse areas such as bioassays, biomedical imaging, and forensics; these properties are, namely: large anti-Stokes shifts, sharp emission spectra and long excited-state lifetimes. The nanomaterials can be utilized for a variety of applications including detection of various analytes, bioimaging, therapies, energy conversion, and security. In this review, we briefly describe the upconversion luminescence process, effective synthetic approaches, and recent literature that elucidate the exceptional properties of these materials and its applications. [ABSTRACT FROM AUTHOR]

This correction notice is for an article titled "Biporous silica nanostructure-induced nanovortex in microfluidics for nucleic acid enrichment, isolation, and PCR-free detection" published in Nature Communications. The correction addresses an error in the introduction of the original article, which has been corrected in both the PDF and HTML versions. The correction clarifies that sample preparation, such as nucleic acid enrichment/isolation, is necessary to detect pathogens during the asymptomatic or pre-symptomatic period. The authors of the article are Eunyoung Jeon, Bonhan Koo, Suyeon Kim, Jieun Kim, Yeonuk Yu, Hyowon Jang, Minju Lee, Sung-Han Kim, Taejoon Kang, Sang Kyung Kim, Rhokyun Kwak, Yong Shin, and Joonseok Lee. [Extracted from the article]

In this research, we investigated to examine the emission characteristics of radioactive carbon emitted from three types of pressurized water reactors. And we examined the possibility of 14C inventory reduction by changing operating conditions of one of the nuclear power plants. Results showed that 14C inventory in the reactor coolant system (RCS) remained constant before the overhaul (O/H) period and more than 90% of the radioactive carbon was found to be organic form. At spent fuel pool, the 14C chemical form of the liquid phase during the O/H period was also dominated by the inorganic (14CO2) form as in the case of the RCS due to the acid oxidized state. We applied gas stripper (G/S) and VCT purge operation to perform the 14C inventory reduction operation for Combustion Engineering type. In the case of gas strippers, approximately 50% of 14C inventory was reduced in the first year and then about 97% in the second year. Unlike our expectations, in case of VCT purge operation, 14C reduction effect was not showed greatly. [ABSTRACT FROM AUTHOR]

Nonnegative matrix factorization (NMF) has been widely used in topic modeling of large-scale document corpora, where a set of underlying topics are extracted by a low-rank factor matrix from NMF. However, the resulting topics often convey only general, thus redundant information about the documents rather than information that might be minor, but potentially meaningful to users. To address this problem, we present a novel ensemble method based on nonnegative matrix factorization that discovers meaningful local topics. Our method leverages the idea of an ensemble model, which has shown advantages in supervised learning, into an unsupervised topic modeling context. That is, our model successively performs NMF given a residual matrix obtained from previous stages and generates a sequence of topic sets. The algorithm we employ to update is novel in two aspects. The first lies in utilizing the residual matrix inspired by a state-of-the-art gradient boosting model, and the second stems from applying a sophisticated local weighting scheme on the given matrix to enhance the locality of topics, which in turn delivers high-quality, focused topics of interest to users. We subsequently extend this ensemble model by adding keyword- and document-based user interaction to introduce user-driven topic discovery. [ABSTRACT FROM AUTHOR]