Mapping of Long-Wavelength Phonon Contribution in the Thermal Transport of Alloyed Semiconductor Superlattices.

The mapping of long-wavelength phonons is important to understand and manipulate the thermal transport in multilayered structures, but it remains a long-standing challenge due to the collective behaviors of phonons. In this study, an experimental demonstration of mapping the long-wavelength phonons in an alloyed Al0.1Ga0.9As/Al0.9Ga0.1As superlattice system is reported. Multiple strategies to filter out the short- to mid-wavelength phonons are used. The phonon mean-free-path-dependent thermal transport properties directly demonstrate both the suppression effect of the ErAs nanoislands and the contribution of long-wavelength phonons. The contribution from phonons with mean free path longer than 1 µm is clearly demonstrated. A model based on the Boltzmann transport equation is proposed to calculate and describe the thermal transport properties, which depicts a clear physical picture of the transport mechanisms. This method can be extended to map different wavelength phonons and become a universal strategy to explore their thermal transport in various application scenarios.

Vesicle formation-related protein CaSec16 and its ankyrin protein partner CaANK2B jointly enhance salt tolerance in pepper.

Vesicle transport plays important roles in plant tolerance against abiotic stresses. However, the contribution of a vesicle formation related protein CaSec16 (COPII coat assembly protein Sec16-like) in pepper tolerance to salt stress remains unclear. In this study, we report that the expression of CaSec16 was upregulated by salt stress. Compared to the control, the salt tolerance of pepper with CaSec16-silenced was compromised, which was shown by the corresponding phenotypes and physiological indexes, such as the death of growing point, the aggravated leaf wilting, the higher increment of relative electric leakage (REL), the lower content of total chlorophyll, the higher accumulation of dead cells, H2O2, malonaldehyde (MDA), and proline (Pro), and the inhibited induction of marker genes for salt-tolerance and vesicle transport. In contrast, the salt tolerance of pepper was enhanced by the transient overexpression of CaSec16. In addition, heterogeneously induced CaSec16 protein did not enhance the salt tolerance of Escherichia coli, an organism lacking the vesicle transport system. By yeast two-hybrid method, an ankyrin protein, CaANK2B, was identified as the interacting protein of CaSec16. The expression of CaANK2B showed a downward trend during the process of salt stress. Compared with the control, pepper plants with transient-overexpression of CaANK2B displayed increased salt tolerance, whereas those with CaANK2B-silenced exhibited reduced salt tolerance. Taken together, both the vesicle formation related protein CaSec16 and its interaction partner CaANK2B can improve the pepper tolerance to salt stress.

A Thermostable Cas12b-Powered Bioassay Coupled with Loop-Mediated Isothermal Amplification in a Customized "One-Pot" Vessel for Visual, Rapid, Sensitive, and On-Site Detection of Genetically Modified Crops.

Genetically modified crops (GMCs) have been discussed due to unknown safety, and thus, it is imperative to develop an effective detection technology. CRISPR/Cas is deemed a burgeoning technology for nucleic acid detection. Herein, we developed a novel detection method for the first time, which combined thermostable Cas12b with loop-mediated isothermal amplification (LAMP), to detect genetically modified (GM) soybeans in a customized one-pot vessel. In our method, LAMP-specific primers were used to amplify the cauliflower mosaic virus 35S promoter (CaMV35S) of the GM soybean samples. The corresponding amplicons activated the trans-cleavage activity of Cas12b, which resulted in the change of fluorescence intensity. The proposed bioassay was capable of detecting synthetic plasmid DNA samples down to 10 copies/µL, and as few as 0.05% transgenic contents could be detected in less than 40 min. This work presented an original detection method for GMCs, which performed rapid, on-site, and deployable detection.

RNA splicing analysis deciphers developmental hierarchies and reveals therapeutic targets in adult glioma.

Widespread alterations in RNA alternative splicing (AS) have been identified in adult gliomas. However, their regulatory mechanism, biological significance, and therapeutic potential remain largely elusive. Here, using a computational approach with both bulk and single cell RNA-sequencing, we uncover a prognostic AS signature linked with neural developmental hierarchies. Using advanced iPSC glioma models driven by glioma driver mutations, we show that this AS signature could be enhanced by EGFRvIII and inhibited by in situ IDH1 mutation. Functional validation of two isoform switching events in CERS5 and MPZL1 shows regulations of sphingolipid metabolism and SHP2 signaling, respectively. Analysis of upstream RNA binding proteins reveals PTBP1 as a key regulator of the AS signature where targeting of PTBP1 suppresses tumor growth and promotes the expression of a neuron marker TUJ1 in glioma stem-like cells. Overall, our data highlights the role of AS in impacting glioma malignance and heterogeneity and its potential as a therapeutic vulnerability for treating adult gliomas.

Characterizing Local Electronic States of Twin Boundaries in Copper.

Grain boundaries (GBs) and twin boundaries (TBs) in copper (Cu) are two major planar defects that influence electrical conductivity due to their complex electron transport characteristics, involving electron scattering and electron concentration. Understanding their local electronic states is crucial for the design of future conductor materials. In this study, we characterized electron behaviors at TBs and GBs within one Cu grain using atomic force microscopy. Our findings revealed that, compared with GBs, TBs exhibit better current transport capability (direct-current mode) and larger electromagnetic loss (high-frequency microwave mode). Both kelvin probe force microscopy and theoretical analysis suggested that TBs with smaller lattice disorder possess lower density of states at the Fermi level. The reduced density of states may result in decreased electron scattering and a lower electron concentration at TBs. The latter can be highlighted by the high-frequency skinning effect, manifested as larger electromagnetic loss and weaker high-frequency conductivity.

A machine learning algorithm-based predictive model for pressure injury risk in emergency patients: A prospective cohort study.

OBJECTIVES: To construct pressure injury risk prediction models for emergency patients based on different machine learning algorithms, to optimize the best model, and to provide a suitable assessment tool for preventing the occurrence of pressure injuries in emergency patients. METHODS: A convenience sampling was used to select 312 patients admitted to the emergency department of a tertiary care hospital in Tianjin, China, from May 2022 to March 2023, and the patients were divided into a modeling group (n = 218) and a validation group (n = 94) in a 7:3 ratio. Based on the results of one-factor logistic regression analysis in the modeling group, three machine learning models, namely, logistic regression, decision tree, and neural network, were used to establish a prediction model for pressure injury in emergency patients and compare their prediction effects. The optimal model was selected for external validation of the model. RESULTS: The incidence of pressure injuries in emergency patients was 8.97 %, 64.52 % of pressure injuries occurred in the sacrococcygeal region, and 64.52 % were staged as stage 1. Serum albumin level, incontinence, perception, and mobility were independent risk factors for pressure injuries in emergency patients (P < 0.05), and the area under the ROC curve of the three models was 0.944-0.959, sensitivity was 91.8-95.5 %, specificity was 72.2-90.9 %, and the Yoden index was 0.677-0.802; the decision tree was the best model that The area under the ROC curve for the validation group was 0.866 (95 % CI: 0.688-1.000), with a sensitivity of 89.8 %, a specificity of 83.3 %, and a Yoden index of 0.731. CONCLUSIONS: The decision tree model has the best predictive efficacy and is suitable for individualized risk prediction of pressure injuries in emergency medicine specialties, which provides a reference for the prevention and early intervention of pressure injuries in emergency patients.

First Report of Rust Disease on Alcea rosea caused by Puccinia modiolae in China.

Alcea rosea, belonging to the Alcea genus in the Malvaceae family, originated from China, but it is now grown worldwide. A. rosea has been widely used in traditional Chinese medicine to alleviate constipation, pain, swelling, and sores. In February 2023, typical symptoms of fungal infection were observed on A. rosea at Guizhou Normal University in Guiyang, Guizhou Province, China. The disease incidence was over 90% (n = 100) for the surveyed A. rosea plants, and the disease severity range from 30% to 90%. The initial symptoms of A. rosea rust were the appearance of chlorotic spots on the leaves. Subsequently, numerous reddish to dark-brown erumpent pustules (telia) were observed. Gradually, the entire plant was covered by rust and the center of each lesion turned brown, necrotic, and ruptured over times, eventually causing defoliation. Voucher specimens of infected A. rosea leaves as representative samples have been deposited at Guizhou Normal University (GNU2023LS008). Telia are round in shape, mostly aggregated in mass, with a diameter of 0.28-0.78 mm (0.46 mm, n = 20). They range in color from reddish-brown to dark brown, and are mainly hypophyllous but occasionally formed on the adaxial leaf surface. The teliospores are fusoid with dimensions of 31.3-93.8 × 10.9-21.3 µm (57.5 × 15.1 µm average, n = 50), hyaline or yellowish to light-brown in color, mostly two-celled, with a smooth wall (1.5-3.0 µm) and a thickened apex (3.0-9.0 µm). However, teliospores which are one-, three-, or four-celled with a notch at the apex, are rarely observed. The morphological characteristics of host symptoms and teliospores were similar to those of Puccinia modiolae (Aime and Abbasi 2018; Albu et al. 2019). For phylogenetic analysis, genomic DNA was extracted from the teliospores of infected leaves. To confirm the species-level identification, PCR was performed on the extracted DNA to amplify the ribosomal DNA internal transcribed spacer (ITS) and large subunit (LSU) regions using primer pairs ITS1/ITS4 (Schoch et al. 2012) and NL1/NL4 (Ziemiecki et al. 1990), respectively. The resulting ITS DNA sequence (GenBank accession no. OR607960) showed 100% identity with P. modiolae sequences (OP369291.1), when the query coverage was 100%. The LSU DNA sequence obtained (OR607961.2) shared 99.85% similarity with P. modiolae (MK458702.1). A phylogenetic tree was constructed using MEGA7.0 and the maximum likelihood method based on the ITS and LSU sequences. The fungal isolates collected in this study and several reference sequences of P. modiolae were grouped within a clade that included the isolates reported on A. rosea in Korea (Ryu et al. 2023), with 100% bootstrap support. Pathogenicity testing was conducted by gently pressing spore powder of naturally diseased leaves onto young leaves of three healthy A. rosea plants, with three noninoculated healthy plants serving as controls. The inoculated and noninoculated plants were kept in a growth chamber at the 26°C with a 12 hour light/dark cycle and 80% humidity. After 2 weeks, all inoculated A. rosea plants showed characteristic disease symptoms of rust infection and telia of P. modiolae, while control plants remained symptomless. The pathogen was identical to that observed on the original diseased leaves. The study results indicate that the causal fungus responsible for the disease is P. modiolae, which has been previously reported on Malvaceae plants (Farr and Rossman 2022). To the best of our knowledge, this is the first report of P. modiolae on A. rosea in China. This study will contribute to an increased understanding of the host range of Puccinia modiolae.

Observation of Free-Boundary-Induced Chiral Anomaly Bulk States in Elastic Twisted Kagome Metamaterials.

Chiral anomaly bulk states (CABSs) can be realized by choosing appropriate boundary conditions in a finite-size waveguide composed of two-dimensional Dirac semimetals, which have unidirectional and robust transport similar to that of valley edge states. CABSs use almost all available guiding space, which greatly improves the utilization of metamaterials. Here, free-boundary-induced CABSs in elastic twisted kagome metamaterials with C_{3v} symmetry are experimentally confirmed. The robust valley-locked transport and complete valley state conversion are experimentally observed. Importantly, the sign of the group velocity near the K and K^{'} points can be reversed by suspending masses at the boundary to manipulate the onsite potential. Moreover, CABSs are demonstrated in nanoelectromechanical phononic crystals by constructing an impedance-mismatched hard boundary. These results open new possibilities for designing more compact, space-efficient, and robust elastic wave macro- and microfunctional devices.

Monolithic Strong Coupling of Topological Surface Acoustic Wave Resonators on Lithium Niobate.

Coherent phonon transfer via high-quality factor (Q) mechanical resonator strong coupling has garnered significant interest. Yet, the practical applications of these strongly coupled resonator devices are largely constrained by their vulnerability to fabrication defects. In this study, topological strong coupling of gigahertz frequency surface acoustic wave (SAW) resonators with lithium niobate is achieved. The nanoscale grooves are etched onto the lithium niobate surface to establish robust SAW topological interface states (TISs). By constructing phononic crystal (PnC) heterostructures, a strong coupling of two SAW TISs, achieving a maximum Rabi splitting of 22 MHz and frequency quality factor product fQm of ≈1.2 × 1013  Hz, is realized. This coupling can be tuned by adjusting geometric parameters and a distinct spectral anticrossing is experimentally observed. Furthermore, a dense wavelength division multiplexing device based on the coupling of multiple TISs is demonstrated. These findings open new avenues for the development of practical topological acoustic devices for on-chip sensing, filtering, phonon entanglement, and beyond.

Focusing Micromechanical Polaritons in Topologically Nontrivial Hyperbolic Metasurfaces.

Vertically stacked multiple atomically thin layers have recently widened the landscape of rich optical structures thanks to these quantum metamaterials or van der Waals (vdW) materials, featuring hyperbolic polaritons with unprecedented avenues for light. Despite their far-reaching implications, most of their properties rest entirely on a trivial band topological origin. Here, a 2D approach is adopted toward a micromechanical vdW analogue that, as a result of engineered chiral and mirror symmetries, provides topologically resilient hyperbolic radiation of mechanical vibrations in the ultrasonic regime. By applying laser vibrometry of the micrometer-sized metasurface, we are able to exhibit the exotic fingerprints of robust hyperbolic radiation spanning several frequencies, which beyond their physical relevance, may enable ultrasonic technologies.

Recent Advances of DNA-Templated Metal Nanoclusters for Food Safety Detection: From Synthesis, Applications, Challenges, and Beyond.

Food safety concerns have become a significant threat to human health and well-being, catching global attention in recent years. As a result, it is imperative to research conceptually novel biosensing and effective techniques for food matrices detection. Currently, DNA-templated metal nanoclusters (DNA-MNCs) are considered as one of the most promising nanomaterials due to their excellent properties in biosensing. While DNA-MNCs have garnered increasing interest, the reviews of design strategies, applications, and futuristic prospects for biosensing have been hardly found especially in food safety. The synthesis of DNA-MNCs and their use as biosensing materials in food contamination detection, including pathogenic bacteria, toxins, heavy metals, residues of pesticides, and others were comprehensively reviewed. In addition, we summarize the properties of DNA-MNCs briefly and discuss the challenges and future trends. The application of DNA-MNCs powered biosensing has been demonstrated and actively studied, which is a promising paradigm for food safety testing that can supplement or even replace current existing methods. Despite the challenges of difficulty regulating accurately, poor stability, low quantum yield, and difficult commercial transformation, the application prospects of DNA-MNCs biosensors are promising. This review aims to provide insights and directions for the future development of DNA-MNCs based food detection technology.

A universal and scalable transformation of bulk metals into single-atom catalysts in ionic liquids.

Single-atom catalysts (SACs) with maximized metal atom utilization and intriguing properties are of utmost importance for energy conversion and catalysis science. However, the lack of a straightforward and scalable synthesis strategy of SACs on diverse support materials remains the bottleneck for their large-scale industrial applications. Herein, we report a general approach to directly transform bulk metals into single atoms through the precise control of the electrodissolution-electrodeposition kinetics in ionic liquids and demonstrate the successful applicability of up to twenty different monometallic SACs and one multimetallic SAC with five distinct elements. As a case study, the atomically dispersed Pt was electrodeposited onto Ni3N/Ni-Co-graphene oxide heterostructures in varied scales (up to 5 cm × 5 cm) as bifunctional catalysts with the electronic metal-support interaction, which exhibits low overpotentials at 10 mA cm-2 for hydrogen evolution reaction (HER, 30 mV) and oxygen evolution reaction (OER, 263 mV) with a relatively low Pt loading (0.98 wt%). This work provides a simple and practical route for large-scale synthesis of various SACs with favorable catalytic properties on diversified supports using alternative ionic liquids and inspires the methodology on precise synthesis of multimetallic single-atom materials with tunable compositions.

Characterization of carbonaceous particles by single particle aerosol mass spectrometer in the urban area of Chengdu, China.

Carbonaceous particles are an important chemical component of atmospheric fine particles. In this study, a single particle aerosol mass spectrometer was used to continuously measure the carbonaceous particles in Chengdu, one of the megacities most affected by haze in China, from January 22 to March 3, 2021. During the observation period, the average mass concentration of PM2.5 was 62.3 ± 37.2 µg m-3, and the emissions from mobile sources were more prominent. Carbonaceous particles accounted for 68.6% of the total particles and could be classified into 10 categories, with elemental carbon (EC) mixed with sulfate (EC-S) particles making the highest contribution (33.1%). EC particles rich in secondary components and organic carbon (OC) particles rich in secondary component exhibited different diurnal variations, suggesting different sources and mixing mechanisms. From "excellent" to "polluted" days, the contributions of EC-S, EC mixed with sulfate and nitrate (EC-SN) and OC mixed with EC (OC-EC) particles increased by 9.8%, 4.5% and 6.6%, respectively, and thus these particles are key targets for future pollution control. The potential source contribution of the southwest area was stronger than that of other areas, and the potential contribution of regional transport to EC-related particles was stronger than to OC-related particles. Most particles were highly mixed with sulfate or nitrate, and the level of secondary mixing further enhanced as pollution worsened.

Generation of a specific aptamer for accurate detection of sarafloxacin based on fluorescent/colorimetric/SERS triple-readout sensor.

Sarafloxacin (SAR), one of the most widely used fluoroquinolone antibiotics, is a serious threat to aquatic environments and human health due to its illegal abuse. Herein, we first screened an aptamer (SAR-1) that specifically binds to SAR using capture-SELEX technology. Based on molecular docking technology, SAR-1 was gradually truncated, and a short SAR-1a with better affinity and specificity was obtained. The optimal SAR-1a was further combined with a Pt nanoparticle (Pt NP)- decorated bimetallic Fe/Co-MOF to fabricate a multimode sensing platform for SAR determination. The Fe/Co-MOF@Pt NPs exhibited excellent peroxidase-like activity, which catalyzed the H2O2-mediated oxidation of 3,3',5,5'-tetramethylbenzidine (TMB), thereby enabling visual detection of SAR. Meanwhile, the generated oxTMB can also produce SERS responses and be used for the SERS detection of SAR. Moreover, the inherent fluorescence property of Fe/Co-MOF@Pt NPs enabled fluorescence detection of SAR. The designed triple-readout aptasensor showed good sensitivity for SAR detection with limits of detection of 0.125 ng/mL (fluorescent mode) and 0.05 ng/mL (colorimetric and SERS mode). The aptamer-based triple-mode sensing platform provided mutual verification of detection results in different output modes, effectively improving the assay accuracy and providing a promising tool for highly sensitive, selective, and accurate determination of SAR in daily life.

Bulk-local-density-of-state correspondence in topological insulators.

In the quest to connect bulk topological quantum numbers to measurable parameters in real materials, current established approaches often necessitate specific conditions, limiting their applicability. Here we propose and demonstrate an approach to link the non-trivial hierarchical bulk topology to the multidimensional partition of local density of states (LDOS), denoted as the bulk-LDOS correspondence. In finite-size topologically nontrivial photonic crystals, we observe the LDOS partitioned into three distinct regions: a two-dimensional interior bulk area, a one-dimensional edge region, and zero-dimensional corner sites. Contrarily, topologically trivial cases exhibit uniform LDOS distribution across the entire two-dimensional bulk area. Our findings provide a general framework for distinguishing topological insulators and uncovering novel aspects of topological directional band-gap materials, even in the absence of in-gap states.

SGC-CLK-1: A chemical probe for the Cdc2-like kinases CLK1, CLK2, and CLK4.

Small molecule modulators are important tools to study both basic biology and the complex signaling of protein kinases. The cdc2-like kinases (CLK) are a family of four kinases that have garnered recent interest for their involvement in a diverse set of diseases such as neurodegeneration, autoimmunity, and many cancers. Targeted medicinal chemistry around a CLK inhibitor hit identified through screening of a kinase inhibitor set against a large panel of kinases allowed us to identify a potent and selective inhibitor of CLK1, 2, and 4. Here, we present the synthesis, selectivity, and preliminary biological characterization of this compound - SGC-CLK-1 (CAF-170). We further show CLK2 has the highest binding affinity, and high CLK2 expression correlates with a lower IC50 in a screen of multiple cancer cell lines. Finally, we show that SGC-CLK-1 not only reduces serine arginine-rich (SR) protein phosphorylation but also alters SR protein and CLK2 subcellular localization in a reversible way. Therefore, we anticipate that this compound will be a valuable tool for increasing our understanding of CLKs and their targets, SR proteins, at the level of phosphorylation and subcellular localization.

Maximum helical dichroism enabled by an exceptional point in non-Hermitian gradient metasurfaces.

Helical dichroism (HD) utilizing unbounded orbital angular momentum degree of freedom, has provided an important means of exploring chiral effects in diverse wave systems, surpassing the two-state constraint in circular dichroism that relies on intrinsic spin. However, the naturally feeble chiral signals that arise during wave-matter interactions pose significant challenges to the effective enlargement of HD. Here, we introduce a new paradigm for realizing maximum HD through non-Hermitian gradient metasurfaces by engineering a chiral exceptional point (EP) in intrinsic topological charge. The non-Hermitian gradient metasurfaces are empowered by the asymmetric coupling feature at the EP, enabling flexible construction to realize versatile chirality control in extreme circumstances where one chiral vortex is totally reflected and the opposite counterpart is completely absorbed or transmitted into the customized vortex modes. As the manifestation of the maximum HD, we present the first experimental demonstration of perfect chirality-selected vortex transmission in acoustics. Our findings open new venues to achieve maximum chirality and explore chiral physics of wave-matter interactions, which can boost many vortical applications in asymmetric chirality manipulation, one-way propagation, and information multiplexing.

Recent advances of food safety detection by nucleic acid isothermal amplification integrated with CRISPR/Cas.

Food safety problems have become one of the most important public health issues worldwide. Therefore, the development of rapid, effective and robust detection is of great importance. Amongst a range of methods, nucleic acid isothermal amplification (NAIA) plays a great role in food safety detection. However, the widespread application remains limited due to a few shortcomings. CRISPR/Cas system has emerged as a powerful tool in nucleic acid detection, which could be readily integrated with NAIA to improve the detection sensitivity, specificity, adaptability versatility and dependability. However, currently there was a lack of a comprehensive summary regarding the integration of NAIA and CRISPR/Cas in the field of food safety detection. In this review, the recent advances in food safety detection based on CRISPR/Cas-integrated NAIA were comprehensively reviewed. To begin with, the development of NAIA was summarized. Then, the types and working principles of CRISPR/Cas were introduced. The applications of the integration of NAIA and CRISPR/Cas for food safety were mainly introduced and objectively discussed. Lastly, current challenges and future opportunities were proposed. In summary, this technology is expected to become an important approach for food safety detection, leading to a safer and more reliable food industry.

Spatiotemporal Acoustic Vortex Beams with Transverse Orbital Angular Momentum.

Recently, the discovery of optical spatiotemporal (ST) vortex beams with transverse orbital angular momentum (OAM) has attracted increasing attention and is expected to extend the research scope and open new opportunities for practical applications of OAM states. The ST vortex beams are also applicable to other physical fields that involve wave phenomena, and here we develop the ST vortex concept in the field of acoustics and report the generation of Bessel-type ST acoustic vortex beams. The ST vortex beams are fully characterized using the scalar approach for the pressure field and the vector approach for the velocity field. We further investigate the transverse spreading effect and construct ST vortex beams with an ellipse-shaped spectrum to reduce the spreading effect. We also experimentally demonstrated the orthogonality relations between ST vortex beams with different charges. Our study successfully demonstrates the versatility of the acoustic system for exploring and discovering spatiotemporally structured waves, inspiring further investigation of exotic wave physics.

A second wave of topological phenomena in photonics and acoustics.

Light and sound are the most ubiquitous forms of waves, associated with a variety of phenomena and physical effects such as rainbows and echoes. Light and sound, both categorized as classical waves, have lately been brought into unexpected connections with exotic topological phases of matter. We are currently witnessing the onset of a second wave of active research into this topic. The past decade has been marked by fundamental advances comprising two-dimensional quantum Hall insulators and quantum spin and valley Hall insulators, whose topological properties are characterized using linear band topology. Here, going beyond these conventional topological systems, we focus on the latest frontiers, including non-Hermitian, nonlinear and non-Abelian topology as well as topological defects, for which the characterization of the topological features goes beyond the standard band-topology language. In addition to an overview of the current state of the art, we also survey future research directions for valuable applications.