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Fouling initiated by nonspecific protein adsorption is a great challenge in biomedical applications, including biosensors, bioanalytical devices, and implants. Poly(dimethylsiloxane) (PDMS), a popular material with many attractive properties for device fabrication in the biomedical field, suffers serious fouling problems from protein adsorption due to its hydrophobic nature, which limits the practical use of PDMS-based devices. Effort has been made to develop biocompatible materials for anti-fouling coatings of PDMS. In this review, typical nonfouling materials for PDMS coatings are introduced and the associated basic anti-fouling mechanisms, including the steric repulsion mechanism and the hydration layer mechanism, are described. Understanding the relationships between the characteristics of coating materials and the accompanying anti-fouling mechanisms is critical for preparing PDMS coatings with desirable anti-fouling properties.

With the rapid development of cybersecurity technologies, cybersecurity testing has played an increasingly critical role in scientific research, new technology validation, system performance evaluation, and talent development. A central challenge in this domain lies in efficiently and rapidly constructing testing environments while ensuring the reliability and reproducibility of test results. To address this issue, this paper proposes an integrated evaluation method specifically designed for cybersecurity testing, combining anomaly detection and predictive analysis techniques. The method first employs an autoencoder (AE) to perform dimensionality reduction on the raw data collected from a testbed environment, followed by anomaly detection using the Isolation Forest (IF) algorithm. To assess the impact of cyberattacks on the stability of the testbed system, the steady-state data of the environment was treated as the ideal reference. The degree of disruption was then quantified by calculating the Euclidean distance between the dimensionally reduced experimental data and the reference state. Finally, a specific case study was conducted to validate the feasibility and effectiveness of the proposed method, and a percentage-based scoring mechanism was introduced to quantitatively evaluate the security level of the system.

We study a joint model where logistic regression is applied to binary longitudinal data with a mismeasured time-varying covariate that is modeled using a mechanistic nonlinear model. Multiple random effects are necessary to characterize the trajectories of the covariate and the response variable, leading to a high dimensional integral in the likelihood. To account for the computational challenge, we propose a stochastic expectation-maximization (StEM) algorithm with a Gibbs sampler coupled with Metropolis–Hastings sampling for the inference. In contrast with previous developments, this algorithm uses single imputation of the missing data during the Monte Carlo procedure, substantially increasing the computing speed. Through simulation, we assess the algorithm’s convergence and compare the algorithm with more classical approaches for handling measurement errors. We also conduct a real-world data analysis to gain insights into the association between CD4 count and viral load during HIV treatment.

High-efficient heat dissipation plays critical role for high-power-density electronics. Experimental synthesis of ultrahigh thermal conductivity boron arsenide (BAs, 1300 W m −1 K −1 ) cooling substrates into the wide-bandgap semiconductor of gallium nitride (GaN) devices has been realized. However, the lack of systematic analysis on the heat transfer across the GaN-BAs interface hampers the practical applications. In this study, by constructing the accurate and high-efficient machine learning interatomic potentials, we perform multiscale simulations of the GaN-BAs heterostructures. Ultrahigh interfacial thermal conductance of 260 MW m −2 K −1 is achieved, which lies in the well-matched lattice vibrations of BAs and GaN. The strong temperature dependence of interfacial thermal conductance is found between 300 to 450 K. Moreover, the competition between grain size and boundary resistance is revealed with size increasing from 1 nm to 1000 μm. Such deep-potential equipped multiscale simulations not only promote the practical applications of BAs cooling substrates in electronics, but also offer approach for designing advanced thermal management systems. Efficient heat dissipation is critical to optimize high-power devices. Here, the authors report high interfacial thermal conductance in GaN-BAs heterostructures and investigate the competition between grain size and boundary resistance by multiscale simulations.

We investigate the effect of superradiance shielding for the analogue rotating black holes simulated by optical vortices by calculating the radial motion of massless particles in such spacetime background. We add the conditions E < L Ω r e and L > 0 to judge the classically forbidden region of superradiance. It is found that the superradiance forbidden region exists near the static limit inside the ergosphere, which will limit the classical Penrose process for the particles with some specific energies and angular momenta. Once these particles satisfying the superradiance conditions are measured at the outside of the ergosphere, this shows that the Penrose process can be quantum.

The spin Hall conductivity (SHC) and anomalous Hall conductivity (AHC) in about 120 full Heusler compounds are calculated using the density functional theory in a high-throughput way. The electronic structures are mapped to the Wannier basis and the linear response theory is used to get the conductivity. Our results show that the mechanism under the SHC or AHC cannot be simply related to the valence electron numbers or atomic weights. It is related to the very details of the electronic structures, which can only be obtained by calculations. A high-throughput calculation is efficient to screen out the desired materials. According to our present results, Rh 2 MnAl and Cu 2 CoSn, as well as Co 2 MnAl and Co 2 MnGa are candidates in spintronic materials regarding their high SHC and AHC values, which can benefit the spin-torque-driven nanodevices.

With the advancements in clock timing technology, increasingly smaller time differences can be distinguished. Therefore, it is critical to investigate the fractional frequency shift of clocks at different locations on Earth. In this paper, we study it systematically under the influence of a subtle lunar tidal potential based on a new method. Our calculations in the geocentric Fermi frame show that when two clocks are located at the same latitude, the longitude difference changes the fractional frequency shift between them. A similar phenomenon occurs when there is a difference in latitude between two clocks on the ground at the same longitude. Interestingly, when the Moon’s longitude changes, the phase and amplitude of the lunar tidal fractional frequency shift between two clocks with the same longitude difference will change, while the change in the Moon’s latitude only affects the amplitude of the fractional frequency shift of these two clocks. Our results provide useful information for the calibration and synchronization of clocks on Earth.

Crustacea, the subphylum of Arthropoda which dominates the aquatic environment, is of major importance in ecology and fisheries. Here we report the genome sequence of the Pacific white shrimp Litopenaeus vannamei , covering ~1.66 Gb (scaffold N50 605.56 Kb) with 25,596 protein-coding genes and a high proportion of simple sequence repeats (>23.93%). The expansion of genes related to vision and locomotion is probably central to its benthic adaptation. Frequent molting of the shrimp may be explained by an intensified ecdysone signal pathway through gene expansion and positive selection. As an important aquaculture organism, L. vannamei has been subjected to high selection pressure during the past 30 years of breeding, and this has had a considerable impact on its genome. Decoding the L. vannamei genome not only provides an insight into the genetic underpinnings of specific biological processes, but also provides valuable information for enhancing crustacean aquaculture. The Pacific white shrimp Litopenaeus vannamei is an important aquaculture species and a promising model for crustacean biology. Here, the authors provide a reference genome assembly, and show that gene expansion is involved in the regulation of frequent molting as well as benthic adaptation of the shrimp.

Plants synthesize an extensive array of secondary metabolites in response to diverse biotic and abiotic stresses. These metabolites function not only as defensive compounds but also constitute significant sources of nutrition and pharmaceuticals. However, the mechanisms governing the synthesis of these secondary metabolites have long been a central focus of research and continue to pose significant challenges. Transcription factors (TFs), serving as key regulators of secondary metabolite synthesis in plants, exhibit mechanisms of action that are still not fully understood. This review summarizes the latest research advancements on how plant transcription factors mediate the regulation of secondary metabolite biosynthesis through various signaling pathways, including light signaling, hormone signaling, MAPK signaling, the ubiquitin-proteasome pathway, epigenetic regulation, microbial interactions, and climate change. A deeper understanding of the mechanisms regulating transcription factors is expected to provide new insights into the biosynthesis of plant secondary metabolites.

What exactly does the oxygen isotopic composition of speleothems tell us about the East Asian monsoon? They provide magnificent, detailed records of hydroclimate, but precisely what aspects of hydroclimate they record is unclear. Zhang et al. present data from two speleothems from central eastern China for the period from 21,000 to 10,000 years ago and suggest that the cause of the oxygen isotopic variability that they observe is more complex than simple changes in monsoon strength or intensity (see the Perspective by McGee). Alternatively, this variation may reflect the lengths of various phases of the monsoon and the regional heterogeneity of the East Asian hydroclimate. Science , this issue p. 580 ; see also p. 518 The paleorecord of the East Asian monsoon reflects much more than simply the amount of rain that fell. Speleothem oxygen isotope records have revolutionized our understanding of the paleo East Asian monsoon, yet there is fundamental disagreement on what they represent in terms of the hydroclimate changes. We report a multiproxy speleothem record of monsoon evolution during the last deglaciation from the middle Yangtze region, which indicates a wetter central eastern China during North Atlantic cooling episodes, despite the oxygen isotopic record suggesting a weaker monsoon. We show that this apparent contradiction can be resolved if the changes are interpreted as a lengthening of the Meiyu rains and shortened post-Meiyu stage, in accordance with a recent hypothesis. Model simulations support this interpretation and further reveal the role of the westerlies in communicating the North Atlantic influence to the East Asian climate.