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Simple Summary: Biodiversity conservation under global climate change is a global challenge. Many wildlife species are altering their distributions to adapt to the changes in their living environments caused by climate change. Amphibians are the most vulnerable group among vertebrates in the context of global climate change, and salamanders are one of the most vulnerable groups among amphibians. The primary threat to salamanders is habitat loss. There have been multiple studies on the potential distribution prediction of umbrella species (umbrella species are those species whose conservation is expected to provide protection for a wide range of co-occurring species due to their extensive habitat requirements), such as the Chinese giant salamander (Andrias davidianus). However, research on rare small salamanders is urgently needed for their conservation under climate change conditions. This study employed an optimized MaxEnt model to predict and analyze the potential distribution and trends of three rare salamanders from Chongqing, China, based on data collected from field surveys, museum collections, and the existing literature. This study assesses the impact of various environmental factors in the context of climate change on three salamanders species with different habitat preferences in Chongqing. It offers implications for the conservation of these salamanders. The Wushan Salamander (Liua shihi), Jinfo Salamander (Pseudohynobius jinfo), and Wenxian Knobby Salamander (Tylototriton wenxianensis) are rare national Class II protected wild animals in China. We performed MaxEnt modeling to predict and analyze the potential distribution and trends of these species in Chongqing under current and future climate conditions. Species distribution data were primarily obtained from field surveys, supplemented by museum collections and the existing literature. These efforts yielded 636 records, including 43 for P. jinfo, 23 for T. wenxianensis, and 570 for L. shihi. Duplicate records within the same 100 m × 100 m grid cell were removed using ENMTools, resulting in 10, 12, and 58 valid distribution points for P. jinfo, T. wenxianensis, and L. shihi, respectively. The optimization of feature class parameters (FC) and the regularization multiplier (RM) were applied using R package "ENMeval 2.0" to establish the optimal model with MaxEnt. The refined models were applied to simulate the suitable distribution areas for the three species. The results indicate that the current suitable habitat area for L. shihi accounted for 9.72% of the whole region of the Chongqing municipality. It is projected that, by 2050, the proportion of suitable habitat will increase to 12.54% but will decrease to 11.98% by 2070 and further decline to 8.80% by 2090. The current suitable habitat area for P. jinfo accounted for 1.08% of the whole region of the Chongqing municipality, which is expected to decrease to 0.31%% by 2050, 0.20% by 2070, and 0.07% by 2090. The current suitable habitat area for T. wenxianensis accounted for 0.81% of the whole region of the Chongqing municipality, which is anticipated to decrease to 0.37% by 2050, 0.21% by 2070, and 0.06% by 2090. Human disturbance, climate variables, and habitat characteristics are the primary factors influencing the distribution of three salamander species in Chongqing. The proximity to roads significantly impacts L. shihi, while climate conditions mainly affect P. jinfo, and the distance to water sources is crucial for T. wenxianensis. The following suggestions were made based on key variables identified for each species: (1) For L. shihi, it is imperative to minimize human disturbances and preserve areas without roads and the existing vegetation within nature reserves to ensure their continued existence. (2) For P. jinfo, the conservation of high-altitude habitats is of utmost importance, along with the reduction in disturbances caused by roads to maintain the species' ecological niche. (3) For T. wenxianensis, the protection of aquatic habitats is crucial. Additionally, efforts to mitigate the impacts of road construction and enhance public awareness are essential for the preservation of this species and the connectivity of its habitats. [ABSTRACT FROM AUTHOR]

The superposition of several optical beams with large mutual angles results in sub‐micrometer periodic patterns with a complex intensity, phase, and polarization structure. For high‐resolution imaging thereof, one often employs optical super‐resolution methods such as scanning nano‐particle imaging. Here, it is reported that by using a conventional arrayed image sensor in combination with 2D Fourier analysis, the periodicities of light fields much smaller than the pixel size can be resolved in a simple and compact setup, with a resolution far beyond the Nyquist limit set by the pixel size. The ability to resolve periodicities with spatial frequencies of ≈3 µm−1, 15 times higher than the pixel sampling frequency of 0.188 µm−1, is demonstrated. This is possible by analyzing high‐quality Fourier aliases in the first Brillouin zone. In order to obtain the absolute spatial frequencies of the interference patterns, simple rotation of the image sensor is sufficient, which modulates the effective pixel size and allows determination of the original Brillouin zone. Based on this method, wavelength sensing with a resolving power beyond 100,000 without any special equipment is demonstrated. [ABSTRACT FROM AUTHOR]

The applications being developed within the U.S. Exascale Computing Project (ECP) to run on imminent Exascale computers will generate scientific results with unprecedented fidelity and record turn-around time. Many of these codes are based on particle-mesh methods and use advanced algorithms, especially dynamic load-balancing and mesh-refinement, to achieve high performance on Exascale machines. Yet, as such algorithms improve parallel application efficiency, they raise new challenges for I/O logic due to their irregular and dynamic data distributions. Thus, while the enormous data rates of Exascale simulations already challenge existing file system write strategies, the need for efficient read and processing of generated data introduces additional constraints on the data layout strategies that can be used when writing data to secondary storage. We review these I/O challenges and introduce two online data layout reorganization approaches for achieving good tradeoffs between read and write performance. We demonstrate the benefits of using these two approaches for the ECP particle-in-cell simulation WarpX, which serves as a motif for a large class of important Exascale applications. We show that by understanding application I/O patterns and carefully designing data layouts we can increase read performance by more than 80 percent. [ABSTRACT FROM AUTHOR]

Inhomogeneous and random scattering in a static-scattering medium diffuses an incident light field into a complex speckle pattern. This phenomenon leads to uncontrolled and unpredictable changes in the spectrum as incident polychromatic light is scattered by the static-scattering medium. In this paper, we propose and demonstrate a novel technique for shaping the randomly scattered spectrum into a controlled mode. The proposed technique is demonstrated experimentally by examples of bandpass spectrum, stairs, right triangle, and Gaussian spectra. A theoretical model for simulating polychromatic light field passing through a scattering medium is also developed. Theoretical and experimental results are consistent. The findings of this paper may present exciting applications, such as compensation for fiber dispersion. [ABSTRACT FROM AUTHOR]

Non-volatile devices, such as SSDs, will be an integral part of the deepening storage hierarchy on large-scale HPC systems. These devices can be on the compute nodes as part of a distributed burst buffer service or they can be external. Wherever they are located in the hierarchy, one critical design issue is the SSD endurance under the write-heavy workloads, such as the checkpoint I/O for scientific applications. For these environments, it is widely assumed that checkpoint operations can occur once every 60 min and for each checkpoint step as much as half of the system memory can be written out. Unfortunately, for large-scale HPC applications, the burst buffer SSDs can be worn out much more quickly given the extensive amount of data written at every checkpoint step. One possible solution is to control the amount of data written by reducing the checkpoint frequency. However, a direct effect caused by reduced checkpoint frequency is the increased vulnerability window of system failures and therefore potentially wasted computation time, especially for large-scale compute jobs. In this paper, we propose a new checkpoint placement optimization model which collaboratively utilizes both the burst buffer and the parallel file system to store the checkpoints, with design goals of maximizing computation efficiency while guaranteeing the SSD endurance requirements. Moreover, we present an adaptive algorithm which can dynamically adjust the checkpoint placement based on the system’s dynamic runtime characteristics and continuously optimize the burst buffer utilization. The evaluation results show that by using our adaptive checkpoint placement algorithm we can guarantee the burst buffer endurance with at most 5% performance degradation per application and less than 3% for the entire system. [ABSTRACT FROM AUTHOR]

The presence of low-valent Nb-based point defects and low surface area are common issues within niobium oxynitrides. Herein, La 3 NbO 7 which has richer basic oxide and lower positive Mulliken charge on Nb(V) than LaNbO 4 , was prepared via NaCl-KCl mixed flux synthesis and converted to perovskite-type LaNbON 2 via thermal ammonolysis. Removal of secondary product La 2 O 3 from ammonolysis of La 3 NbO 7 gives rise to additional nanopores in LaNbON 2 besides the pores resulted from nitridation. This makes a bigger specific surface area (23 m 2 /g) than conventional LaNbON 2 prepared from LaNbO 4 (11 m 2 /g). Moreover, UV–vis spectrum of LaNbON 2 from La 3 NbO 7 reveals much lower defect absorption than LaNbON 2 from LaNbO 4 ; thermogravimetric analysis shows that the mass-gain stage attributed to oxidation of low-valent Nb is present in curve of LaNbON 2 from LaNbO 4 while absent in that of LaNbON 2 from La 3 NbO 7 . These indicate that the formation of low-valent Nb defects in LaNbON 2 is inhibited when using La 3 NbO 7 as precursor. [ABSTRACT FROM AUTHOR]

We report the all-angle dual optical and acoustic waveguides in defect-free phoxonic crystals. The realization of this function relies on dual flat open equal-frequency contours (EFCs) enabling all-angle self-collimation for both optical and acoustic waves. For incident angles within 85°, both light and sound can propagate simultaneously along the propagation direction without diffraction in the proposed defect-free structure. As a potential application of our work, a compact 3 dB phoxonic Y-shaped beam splitter is designed and numerically demonstrated. The coexistence of all-angle optical and acoustic self-collimation allows a new potential possibility to realize integrated management of photons and phonons with an ultracompact footprint size. • For the first time, we achieve synchronous all-angle self -collimation of both light and sound waves. • A compact 3 dB phoxonic Y-shaped beam splitter is also achieved. • Our work has potential application in the integrated management of photons and phonons with an ultracompact footprint size. [ABSTRACT FROM AUTHOR]

Nowadays, data reduction is becoming increasingly important in dealing with the large amounts of scientific data. Existing multilevel compression algorithms offer a promising way to manage scientific data at scale, but may suffer from relatively low performance and reduction quality. In this paper, we propose MGARD+, a multilevel data reduction and refactoring framework drawing on previous multilevel methods, to achieve high-performance data decomposition and high-quality error-bounded lossy compression. Our contributions are four-fold: 1) We propose to leverage a level-wise coefficient quantization method, which uses different error tolerances to quantize the multilevel coefficients. 2) We propose an adaptive decomposition method which treats the multilevel decomposition as a preconditioner and terminates the decomposition process at an appropriate level. 3) We leverage a set of algorithmic optimization strategies to significantly improve the performance of multilevel decomposition/recomposition. 4) We evaluate our proposed method using four real-world scientific datasets and compare with several state-of-the-art lossy compressors. Experiments demonstrate that our optimizations improve the decomposition/recomposition performance of the existing multilevel method by up to $70 \times$ 70 × , and the proposed compression method can improve compression ratio by up to $2 \times$ 2 × compared with other state-of-the-art error-bounded lossy compressors under the same level of data distortion. [ABSTRACT FROM AUTHOR]

Pathological cardiac hypertrophy is associated with adverse cardiovascular events and can gradually lead to heart failure, arrhythmia, and even sudden death. However, the current development of treatment strategies has been unsatisfactory. Therefore, it is of great significance to find new and effective drugs for the treatment of myocardial hypertrophy. We found that carnosol can inhibit myocardial hypertrophy induced by PE stimulation, and the effect is very significant at 5 μM. Moreover, we demonstrated that 50 mg/kg of carnosol protect against cardiac hypertrophy and fibrosis induced by TAC surgery in mice. Mechanically, we proved that the inhibitory effect of carnosol on cardiac hypertrophy depends on its regulation on the phosphorylation activation of AMPK. In conclusion, our study suggested that carnosol may be a novel drug component for the treatment of pathological cardiac hypertrophy. • Carnosol inhibited the hypertrophy of neonatal rat cardiomyocytes induced by PE. • RNA sequencing results showed carnosol treatment activates the protein synthesis pathway. • Carnosol reduces cardiac hypertrophy, dysfunction, and fibrosis induced by TAC surgery in mice. • AMPK pathway is involved in regulating the inhibitory process of carnosol on myocardial hypertrophy. [ABSTRACT FROM AUTHOR]

In this work, supercontinuum (SC) generation in three kinds of step-index highly nonlinear fibres (HNLFs) are experimentally investigated. The generated SC spectra are compared with each other by changing the numbers and wavelengths of the pump sources, and also by employing the HNLFs with different refractive-index differences between the core and the cladding. The widest spectral range of generated SC was about 2650 nm covering from 350 to 3000 nm when using the three pump wavelengths of 800, 1400 and 1867 nm. The results demonstrate that the step-index HNLFs have excellent performances for SC generation and great potentials for the realization of all-fibre SC source. [ABSTRACT FROM AUTHOR]

Highly crystalline (110) layered perovskite Sr 2 Nb 2 O 7 , (111) layered perovskite Sr 5 Nb 4 O 15 and complex perovskite Sr 4 Nb 2 O 9 were prepared by NaCl-KCl flux growth method from SrCO 3 and Nb 2 O 5 . This flux synthesis achieves single strontium niobate phase in contrast to mixed niobates from the solid state reaction with the same heating parameters. A little excess of Sr source was found to be required for the synthesis of Sr 5 Nb 4 O 15 and Sr 4 Nb 2 O 9 at elevated temperature due to slight evaporation. The three strontium niobates were converted to perovskite SrNbO 2 N via thermal ammonolysis under NH 3 flow at 900 °C. Post-wash treatment was performed to remove the byproduct SrO. This makes additional nanopores in SrNbO 2 N in the cases of Sr 5 Nb 4 O 15 and Sr 4 Nb 2 O 9 , and results in increasing surface areas of SrNbO 2 N with Sr:Nb ratios in the precursors (from 9.9 to 19.8 and 35.5 m 2 /g). On the other hand, the UV–Vis diffusion reflectance spectra reveal decreasing light absorption by defects in SrNbO 2 N in this order. This suggests fewer low-valent Nb defects in SrNbO 2 N prepared from precursor with higher Sr:Nb ratio. SrNbO 2 N prepared from Sr 4 Nb 2 O 9 would be advantageous for applications that require high surface area and low defect density of the material. [ABSTRACT FROM AUTHOR]

The speckle pattern is formed by a laser beam through a scattering medium. It has been demonstrated that a bright focal spot can be obtained after optimizing the phase of the incident light. In this paper, we study the influence of the beam coherence on the focusing of laser beam through scattering media. We impose a dynamic random phase map onto a laser beam, to achieve partially coherent light with controlling coherence. It is shown that the speckle can be suppressed when the coherence of the light beam is low. We find that even when the partially coherent light beam is focusing through the scattering media, a focal spot is also generated by modulating the light beam’s wavefront. It is also found that the intensity of the focal spot decreases with a decrease in the coherence of the beam. Moreover, the lower is the coherence of the light beam, and the smaller is the size of the focal spot. The results of this paper can pave a way applying partially coherent light in optical phase optimization and optical imaging. [ABSTRACT FROM AUTHOR]