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The precise controllability of the Fermi level is a critical aspect of quantum materials. For topological Weyl semimetals, there is a pressing need to fine-tune the Fermi level to the Weyl nodes and unlock exotic electronic and optoelectronic effects associated with the divergent Berry curvature. However, in contrast to two-dimensional materials, where the Fermi level can be controlled through various techniques, the situation for bulk crystals beyond laborious chemical doping poses significant challenges. Here, we report the milli-electron-volt (meV) level ultra-fine-tuning of the Fermi level of bulk topological Weyl semimetal tantalum phosphide using accelerator-based high-energy hydrogen implantation and theory-driven planning. By calculating the desired carrier density and controlling the accelerator profiles, the Fermi level can be experimentally fine-tuned from 5 meV below, to 3.8 meV below, to 3.2 meV above the Weyl nodes. High-resolution transmission electron microscopy reveals the crystalline structure is largely maintained under irradiation, while electrical transport indicates that Weyl nodes are preserved and carrier mobility is also largely retained. Our work demonstrates the viability of this generic approach to tune the Fermi level in semimetal systems and could serve to achieve property fine-tuning for other bulk quantum materials with ultrahigh precision. [ABSTRACT FROM AUTHOR]

As a significant source of nutrients and other components into the coastal ocean, submarine groundwater discharge (SGD) is a combination of multiple spatial‐temporal scale processes, including fresh terrestrial groundwater (FSGD), recirculating seawater (RSGD), and porewater exchange (PEX). Quantifying the different types of SGD is extremely important for understanding the coastal biogeochemical cycles of various materials. The green tide bloom in the southern Yellow Sea (China) has attracted increasing attention during the past decade. Haizhou Bay is thought to be an important green tide proliferating area, but the source of an apparent high supply of nutrients has not been identified yet. We report here on our investigations of the distribution patterns of Ra and Rn isotopes in groundwater and seawater in Haizhou Bay. By solving a combined mass balance for 224Ra, 223Ra, 226Ra, and 222Rn, we estimated that the bay's water residence time is 28.8 days, FSGD is highest at 3.6 cm d−1, RSGD is 2.7 cm d−1, and PEX is lowest at 0.6 cm d−1. The total SGD into Haizhou Bay is estimated at 9.40 × 107 m3 d−1 (6.9 cm d−1), about 12 times that of the local river discharge into the bay. SGD‐derived nutrients are shown to play an important role when considered among all known nutrient sources. Our results suggest that dissolved inorganic nitrogen (DIN) and silicate (DSi) are transported by SGD mainly via FSGD. We also note that the phosphorus (DIP) budget is heavily influenced by RSGD. Plain Language Summary: Submarine groundwater discharge (SGD) has been drawing attention as an important benthic boundary exchange pathway in the global marginal seas. As any water flow entering the sea, SGD may happen on small scales (centimeters, minutes to hours) as porewater exchange (PEX), and/or large scales (>meters, days to seasons) as fresh groundwater discharge (FSGD) and seawater recirculation (RSGD) in the subterranean estuary. To better understand its significance, it is necessary to interpret multi‐scale SGD processes and quantify associated nutrients fluxes accordingly. In this study, different types of SGD and associated nutrient fluxes were quantified based on multiple radium and radon isotopes in Haizhou Bay, China, which is one of the world's largest green tide proliferating areas. The FSGD and RSGD were found to be the main processes, accounting for more than 90% of the total SGD fluxes. SGD was recognized as a key nutrient source in Haizhou Bay, which is more than one order of magnitude higher than that of the local river discharge. This study highlights the crucial role of benthic boundary exchange for the health of marine ecosystem and sustainability of the future ocean. Key Points: Multi‐scale submarine groundwater discharge processes were differentiated and quantified via a multi‐isotope mass balance approachThe flux of fresh groundwater was about 30% higher than recirculated saline groundwater, and about 6 times higher than porewater exchangeFresh groundwater is a main nutrient source to Haizhou Bay, but recirculated saline groundwater makes a larger contribution to DIP inputs [ABSTRACT FROM AUTHOR]

Seafloor ambient noise in the Arctic Ocean is related to sea ice. The characteristics of low‐frequency seafloor ambient noise (<10 Hz) in the northern Chukchi Sea have rarely been reported. Here, we investigated the seafloor ambient noise recorded using ocean‐bottom seismometers in the northern Chukchi Sea under four different sea ice‐concentration periods from 3 to 23 August 2020, in the 11th Chinese National Arctic Research Expedition. The causes and mechanisms of the changes in seafloor ambient noise that correspond to the variation in sea ice concentration were discussed. The energy of infragravity waves and primary microseisms is weak compared with other oceans. Combined with the analysis of land station, we argue that the variations in sea ice extent have little effect on the energy of the primary microseisms and infragravity waves. The power of secondary microseisms is growth with the loss of sea ice and is influenced by storms. We find that a high concentration of sea ice can impede the process of storm‐sea surface interaction, which in turn affects the power of microseisms inspired by storm. [ABSTRACT FROM AUTHOR]

Amidst global climate change and unsustainable human exploitation of water resources, water has emerged as a critical factor constraining global agricultural food production and ecological environments. Particularly in agricultural powerhouses like China, irrigation water accounts for a significant portion of freshwater resource utilization. However, the inefficiency of irrigation water usage has become a weak link in water resource management. To better assess irrigation water efficiency, an accurate estimation of regional irrigated areas is urgently needed. This study proposes a method for identifying actual irrigated areas based on remote sensing-derived evapotranspiration (ET) to address the challenge of accurately interpreting irrigated areas in tropical regions. Using Yunnan Province's Yuanmou irrigation district as a case study, this research combined ground monitoring data and remote sensing data to identify actual irrigated areas through ET inversion and downscaling methods using the Penman–Monteith–Leuning (PML) model. In 2023, the total irrigated area interpreted from remote sensing in the study area was approximately 15,000 hm2, with a comparison against validation points revealing an extraction error of 16%. The small error indicates that this method can effectively enhance the reliability of monitoring actual irrigated areas, thus providing valuable data support for agricultural irrigation water management. [ABSTRACT FROM AUTHOR]

Most Penman-Monteith-Leuning (PML) evapotranspiration (ET) modeling studies are dominated by consideration of meteorological, energy, and land use information, etc., but the dynamic coupling of soil moisture content (SM), especially in terms of improving accuracy through assimilation, lacks sufficient attention. This paper proposes a research framework for the dynamic coupling simulation of PML model and SM based on data assimilation, i.e., the remote sensing monitored SM is combined with soil evaporation of PML to obtain high-precision time-continuous SM data through data assimilation; simultaneously, dynamical soil evaporation coefficients are generated based on the assimilated SM to improve the simulation accuracy of the PML model. The new scheme was validated at a typical irrigation zone in north China and showed obvious improvements in both SM and ET simulations. Moreover, the effect of the assimilation of SM on the simulation accuracy of ET for different crop growth periods is further analyzed. This research provides a new idea for the coupling simulation of the SM and PML models. [ABSTRACT FROM AUTHOR]

Diffusion in alloys is an important class of atomic processes. However, atomistic simulations of diffusion in chemically complex solids are confronted with the timescale problem: the accessible simulation time is usually far shorter than that of experimental interest. In this work, long‐timescale simulation methods are developed using reinforcement learning (RL) that extends simulation capability to match the duration of experimental interest. Two special limits, RL transition kinetics simulator (TKS) and RL low‐energy states sampler (LSS), are implemented and explained in detail, while the meaning of general RL are also discussed. As a testbed, hydrogen diffusivity is computed using RL TKS in pure metals and a medium entropy alloy, CrCoNi, and compared with experiments. The algorithm can produce counter‐intuitive hydrogen‐vacancy cooperative motion. We also demonstrate that RL LSS can accelerate the sampling of low‐energy configurations compared to the Metropolis–Hastings algorithm, using hydrogen migration to copper (111) surface as an example. [ABSTRACT FROM AUTHOR]

The segmented structure can effectively improve the performance of a thermoelectric generator (TEG), but the interfacial thermal stress between adjacent segments seriously threatens the reliability of segmented TEGs. Noticing this, we investigate the mechanical performance of a segmented TEG via theoretical and numerical methods. Results show that the structural stress depends on the ratio of cross-sectional areas between p- and n-type TE legs rather than the absolute cross-sectional areas, while the height ratio of different segments has a significant influence on structural stress. Different from structural stress, the thermal stress induced by unmatched thermal expansion between different segments increases rapidly with the increase of cross-sectional area, and can easily exceed 20% of the total interfacial stress. Besides, both the conversion efficiency and interfacial stress can be optimized by adjusting the ratio of cross-sectional areas. Our results provide the theoretical basis and guidance in the design of segmented TEGs. [ABSTRACT FROM AUTHOR]

Antarctic krill protein–iron complex and peptide–iron complex were acquired to investigate their iron bioavailability, expression of iron-regulated genes, and in vivo antioxidant capacity. Results indicated that the Antarctic krill peptide–iron complex significantly increased the hemoglobin (Hb), serum iron (SI), and iron contents in the liver and spleen in iron-deficiency anemia (IDA) mice (p < 0.05) compared with those of the Antarctic krill protein–iron complex. Despite the gene expressions of the divalent metal transporter 1(DMT1), the transferrin (Tf), and the transferrin receptor (TfR) being better regulated by both Antarctic krill peptide–iron complex and protein–iron complex, the relative iron bioavailability of the Antarctic krill peptide–iron complex group (152.53 ± 21.05%) was significantly higher than that of the protein–iron complex group (112.75 ± 9.60%) (p < 0.05). Moreover, Antarctic krill peptide–iron complex could enhance the antioxidant enzyme activities of superoxidase dismutase (SOD) and glutathione peroxidase (GSH-Px), reduce the malondialdehyde (MDA) level in IDA mice compared with the protein–iron complex, and reduce the cell damage caused by IDA. Therefore, these results indicated that Antarctic krill peptide–iron complex could be used as a highly efficient and multifunctional iron supplement. [ABSTRACT FROM AUTHOR]

Most of the current parameterization schemes for the Penman–Monteith–Leuning evapotranspiration (ET) model (PML) consider meteorological and energy factors and land use types, but the analysis of the effect of soil moisture (SM) changes on ET processes lacks sufficient attention. This paper proposes a parameterization scheme for the sensitive parameters of the PML model considering soil water content, i.e., coupling the land surface SM in the calculation of soil evaporation coefficient f and coupling the SM of the root zone layer in the calculation of maximum stomatal conductance g s x , respectively. The new parameterization scheme is validated at 13 flux sites worldwide and showed significant improvements in improving the correlation with measured values. Moreover, based on the analysis of the spatial distribution of soil evaporation and vegetation transpiration, and the correlation between SM and ET, the regional characteristics of the effect of SM on ET are further revealed. This study provides a new idea for conducting the fusion simulation of SM based on a PML model, which is useful for the subsequent development of the model. [ABSTRACT FROM AUTHOR]

Civilian fusion demands structural materials that can withstand the harsh environments imposed inside fusion plasma reactors. The structural materials often transmute under 14.1 MeV fast neutrons, producing helium (He), which embrittles the grain boundary (GB) network. Here, it is shown that neutron‐friendly and mechanically strong nano‐phases with atomic‐scale free volume can have low He‐embedding energy Eemb${\mathcal{E}}_{\mathrm{emb}}$ and >10 at.% He‐absorbing capacity, and can be especially advantageous for soaking up He on top of resisting radiation damage and creep, provided they have thermodynamic compatibility with the matrix phase, satisfactory equilibrium wetting angle, as well as a high enough melting point. The preliminary experimental demonstration proves that Eemb${\mathcal{E}}_{\mathrm{emb}}$ is a good ab initio predictor of He shielding potency in nano‐heterophase materials, and thus, Eemb${\mathcal{E}}_{\mathrm{emb}}$ is used as a key feature for computational screening. In this context, a list of viable compounds expected to be good He‐absorbing nano‐phases is presented, taking into account Eemb${\mathcal{E}}_{\mathrm{emb}}$, the neutron absorption and activation cross‐sections, the elastic moduli, melting temperature, the thermodynamic compatibility, and the equilbrium wetting angle of the nano‐phases with the Fe matrix as an example. [ABSTRACT FROM AUTHOR]

Keywords: intervertebral disc degeneration; spinal fusion; lymphocyte to monocyte ratio; prognostic factor EN intervertebral disc degeneration spinal fusion lymphocyte to monocyte ratio prognostic factor 2879 2891 13 10/07/22 20220901 NES 220901 Introduction Lumbar disc degenerative (LDD) predisposes to cause secondary disorders such as lumbar disc herniation, lumbar spondylolisthesis, and lumbar spinal stenosis, the main cause of lower back pain and neuralgia. Additionally, the ROC curve of LMR prediction of severe degeneration showed that patients with LMR < 3.16 had severer degeneration. Further, we should note that although the AUC of LMR in this study did not reach more than 0.7 in predicting severe disc degeneration and fusion failure, correlation analysis and multivariate regression analysis have shown that low LMR is significantly associated with severe disc degeneration and fusion failure. [Extracted from the article]

Objective: To determine if preoperative albumin-alkaline phosphatase ratio (AAPR) is predictive of clinical outcomes in patients with degenerative lumbar diseases undergoing lumbar fusion. Method: 326 patients undergoing posterior lumbar decompression and fusion were retrospectively analyzed. The cumulative grade was calculated by summing the Pfirrmann grades of all lumbar discs. Grouping was based on the 50th percentile of cumulative grade. The relationship between AAPR, intervertebral disc degeneration (IDD) severity, and fusion rate was explored using correlation analyses and logistic regression models. Meanwhile, the ROC curve evaluated the discrimination ability of AAPR in predicting severe degeneration and non-fusion. Results: High AAPR levels were significantly negatively correlated with severe degeneration and non-fusion rate. A multivariate binary logistic analysis revealed that high preoperative AAPR was an independent predictor of severe degeneration and postoperative non-fusion (OR: 0.114; 95% CI: 0.027–0.482; p = 0.003; OR: 0.003; 95% CI: 0.0003–0.022; p < 0.001). The models showed excellent discrimination and calibration. The areas under the curve (AUC) of severe degeneration and non-fusion identified by AAPR were 0.635 and 0.643. Conclusion: The AAPR can help predict the severity of disc degeneration and the likelihood of non-fusion. [ABSTRACT FROM AUTHOR]

A novel class of secondary amines with long chains containing ether bonds were synthesized by a three-step protection–etherification–deprotection process from diethanolamine. The optimum reaction conditions were examined. This method has the advantages of simplicity, low cost, and high yield. Furthermore, some new downstream products (diglycolamides) were prepared from the ether-containing long-chain secondary amines as reactants, and their loading capacities in extractions of several metal ions were evaluated. [ABSTRACT FROM AUTHOR]