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Source term investigation is a critically important aspect of reactor decommissioning, particularly as the range of nuclides under consideration expands beyond the capabilities of existing analysis methods. In this study, we try to propose a methodology to indirectly determine the radioactivity of long-lived nuclides which are non-γ or low energy in various nuclear waste materials by measuring the radioactivity of 60Co. The critical point of this method is to establish relationship between some easy to measure (ETM) key nuclides, such as certain γ emitters (like 60Co), and the difficult to measure (DTM) nuclides to derive information for the DTM nuclides of interest. To begin, we calculate nuclide bulk densities of 55Fe, 60Co, 63Ni and 152Eu in nuclear waste materials. By constructing inversion matrices and analyzing the intensity matrices of characteristic γ lines emitted by 60Co, we can extract the radioactivity of non-γ radionuclides (55Fe, 63Ni, and 152Eu) present in the nuclear waste materials that are contained within a specific container. Furthermore, our methodology accounts for the influence of voids within the container, thereby ensuring the reliability and validity of the obtained results. This innovative approach offers a promising avenue for efficiently sorting nuclear waste.

API calls are programming interfaces used by applications. When it is difficult for an analyst to perform a direct reverse analysis of a program, the API provides an important basis for analyzing the behavior and functionality of the program. API address spaces are essential for analysts to identify API call information, and therefore API call obfuscation is used as a protection strategy to prevent analysts from obtaining call information from API address spaces. API call obfuscation avoids direct API calls and aims to create a more complex API calling process. Unfortunately, current API call obfuscation methods are not effective in preventing analysts from obtaining usable information from the API address space. To solve this issue, in this paper, we propose an API call obfuscation model based on address space obscurity. The key functions within the API are encrypted and moved to the user code space for execution. This breaks the relationship between the API and its address space, making it impossible for analysts to obtain address information about a known API from the API address space. In our experiments, we developed an archetypical compiler-level API call obfuscation system to automate the obfuscation of input source code into an obfuscated file. The results show that our approach can thwart existing API deobfuscation techniques and is highly resistant to various open-source dynamic analysis platforms. Compared to other obfuscation techniques, our scheme improves API address space obscurity by more than two times, the detection rate of deobfuscation techniques such as Scylla, etc. is zero, and the increase in obfuscation overhead is not more than 20%. The above results show that APIASO has better obfuscation effect and practicability.

Regulating the adsorption behaviour of the polysulfide species is the key to achieving highly stable Li-S batteries. Here, the authors show that amorphization-induced redistribution of d orbitals enable CoO to be a favourable candidate for polysulfide adsorption and conversion.

Represented by reactive security defense mechanisms, cyber defense possesses a static, reactive, and deterministic nature, with overwhelmingly high costs to defend against ever-changing attackers. To change this situation, researchers have proposed moving target defense (MTD), which introduces the concept of an attack surface to define cyber defense in a brand-new manner, aiming to provide a dynamic, continuous, and proactive defense mechanism. With the increasing use of machine learning in networking, researchers have discovered that MTD techniques based on machine learning can provide omni-bearing defense capabilities and reduce defense costs at multiple levels. However, research in this area remains incomplete and fragmented, and significant progress is yet to be made in constructing a defense mechanism that is both robust and available. Therefore, we conducted a comprehensive survey on MTD research, summarizing the background, design mechanisms, and shortcomings of MTD, as well as relevant features of intelligent MTD that are designed to overcome these limitations. We aim to provide researchers seeking the future development of MTD with insight into building an intelligently affordable, optimized, and self-adaptive defense mechanism.

Summary: Achieving high selectivity and activity with the oxygen reduction reaction (ORR) is significant for developing efficient energy conversion techniques and chemical production. Here, we report that selective ORRs can be achieved by tuning short-range order in amorphous and crystalline NiO nanosheets (a-NiO NSs and c-NiO NSs, respectively). X-ray absorption spectroscopy analysis reveals that the short-range order of a-NiO NSs and c-NiO NSs mainly adopt the NiO5 pyramidal and NiO6 octahedral structures, respectively. The a-NiO NSs for electrochemical H2O2 production in 0.1 M KOH exhibits both high selectivity over 90% and high activity (1 mA cm−2 at 0.66 V versus RHE), while c-NiO NSs tends to catalyze ORRs through 4-electron pathways to generate H2O. Theoretical calculations indicate that the changed short-range order of a-NiO NSs leads to alteration of Ni d-orbital states, which can regulate the adsorption orientation and strength of ∗OOH intermediates to achieve high selectivity and activity of 2-electron ORRs.

Sintering supported metal nanoparticles is the common route to the deactivation of industrial heterogeneous catalysts. Here, the authors report a carbon atomization process that allows one not only to redisperse metal nanoparticles, but also to recover deactivated catalysts.

Vesicular neurotransmitter transporters (VNTs) mediate the selective uptake and enrichment of small-molecule neurotransmitters into synaptic vesicles (SVs) and are therefore a major determinant of the synaptic output of specific neurons. To identify novel VNTs expressed on SVs (thus identifying new neurotransmitters and/or neuromodulators), we conducted localization profiling of 361 solute carrier (SLC) transporters tagging with a fluorescent protein in neurons, which revealed 40 possible candidates through comparison with a known SV marker. We parallelly performed proteomics analysis of immunoisolated SVs and identified seven transporters in overlap. Ultrastructural analysis further supported that one of the transporters, SLC35D3, localized to SVs. Finally, by combining metabolite profiling with a radiolabeled substrate transport assay, we identified UDP-glucose as the principal substrate for SLC35D3. These results provide new insights into the functional role of SLC transporters in neurotransmission and improve our understanding of the molecular diversity of chemical transmitters.

While noble metal usage in catalysis is ubiquitous, the metals’ scarcity necessitates new materials designs for efficient utilization. Here, authors report a general strategy to prepare amorphous noble metal nanosheets and find the nanomaterials to act as efficient water-splitting electrocatalysts.

In this experiment, the effect of replacing milk fat with soybean fat body (25%, 50%, 75%, 100%) on the quality, antioxidant capacity and in vitro digestive characteristics of yogurt was investigated while maintaining the total fat content of the yogurt unchanged. The results showed that increasing the substitution amount of soy fat body for milk fat had little effect on the pH and acidity of yogurt during the storage period, while the physicochemical properties, degree of protein gel network crosslinking, saturated fatty acid content, PV value and TBARS value of the yogurt significantly decreased (p < 0.05). Meanwhile, protein content, solids content, unsaturated fatty acid content, tocopherol content and water holding capacity significantly increased (p < 0.05). Flavor analysis revealed that yogurts with soybean oil bodies were significantly different when compared to those without soybean oil bodies (p < 0.05), and yogurt with 25% substitution had the highest sensory score. After in vitro digestion, the free fatty acid release, antioxidant capacity and protein digestibility of soybean oil body yogurt were significantly higher (p < 0.05). The SDS-PAGE results showed that the protein hydrolysis of the soybean oil body yogurt was faster. Therefore, the use of an appropriate amount of soybean oil bodies to replace milk fat is able to enhance the taste of yogurt and improve the quality of the yogurt.

Summary: The size and shape control of amorphous nanomaterials has long been a bottleneck restricting their further development. Here, we present a general approach to synthesize more than twenty kinds of amorphous metal oxide nanosheets. The amorphous state of the nanosheets is determined using aberration-corrected high-resolution transmission electron microscopy and X-ray diffraction. By using extended X-ray absorption fine structure analysis, we demonstrate that amorphous nanosheets have a larger interatomic distance and a looser packing characteristic compared with crystalline counterparts. The as-prepared amorphous FeOx nanosheets are used as sodium-ion batteries anode materials, exhibiting notable performance with a specific capacity of 263.4 mAh g−1 at 100 mA g−1 and long-term cyclic stability. Significantly, a reversible amorphous-crystalline-amorphous structure transformation phenomenon during the cycling test is observed at the atomic scale.

Background The temporal sequence between serum calcium and insulin resistance (IR) and their effects on hypertension are unclear. We studied the association between serum calcium and IR, with risk of hypertension events in a longitudinal cohort conducted in China. Methods and Results Data from 8653 subjects aged 20 to 74 years with an average follow‐up of 5.3 years were analyzed. Serum calcium, and fasting and 2‐hour serum glucose and insulin were measured at baseline and follow‐up. Cross‐lagged panel and mediation analysis were used to examine the temporal relationship between serum calcium and IR and its impact on hypertension incidence. The conjoint effects of serum calcium and IR at baseline on hypertension at follow‐up were observed (P=0.029 for HOMA_IR [hepatic IR] and P=0.009 for Gutt index [peripheral IR]). The cross‐lagged path coefficient (β2) from baseline serum calcium to follow‐up peripheral IR were significantly greater than path coefficient (β1) from baseline peripheral insulin resistance to follow‐up serum calcium (β2 =−0.354 versus β1=−0.005; P=0.027). However, no directional relationships were observed in the serum calcium↔hepatic IR analysis. The mediation effect of peripheral IR on the association of serum calcium at baseline with hypertension at follow‐up was estimated at 16.4% (P

Karst tunnels commonly pass through large karst caves during their construction and operation. Although treatment technologies are relatively mature, a systematic treatment method to guide the selection of treatment technologies is lacking. To solve this problem, a spatial decomposition method (SDM) of large karst caves is proposed that is based on analyzing the spatial relationship between tunnels and karst caves and summarizing the relevant treatment techniques. In this method, the space between the tunnel and the cavern is divided into eight parts using a space dividing line (SDL), which makes the spatial position relationship between the tunnel and cavern more intuitive. A geometric model of the SDM is established, and the numerical values of each geometric parameter are determined by field surveys and drawings. Constructing a three-dimensional spatial diagram by applying relevant parameters to the geometric model provides a reference for selecting a treatment technology. The SDM of the arch top, arch bottom, and two wings matching the treatment technology is proposed. Seven principles of technical selection—namely, safety, convenience, scientificity, sustainability, economy, feasibility, and openness—are mentioned in order to overcome the difficulty of technology selection due to such factors as technological diversity, materials, equipment, and environment. Finally, the SDM is used to solve the problem of the Shangyuan tunnel passing through a large karst cave. The implementation of the SDM in tunnel construction would represent a significant breakthrough and has important engineering value in solving the problem of tunnel passes through large karst caves.

The correct establishment and maintenance of unidirectional Notch signaling are critical for the homeostasis of various stem cell lineages. However, the molecular mechanisms that prevent cell-autonomous ectopic Notch signaling activation and deleterious cell fate decisions remain unclear. Here we show that the retromer complex directly and specifically regulates Notch receptor retrograde trafficking in Drosophila neuroblast lineages to ensure the unidirectional Notch signaling from neural progenitors to neuroblasts. Notch polyubiquitination mediated by E3 ubiquitin ligase Itch/Su(dx) is inherently inefficient within neural progenitors, relying on retromer-mediated trafficking to avoid aberrant endosomal accumulation of Notch and cell-autonomous signaling activation. Upon retromer dysfunction, hypo-ubiquitinated Notch accumulates in Rab7+ enlarged endosomes, where it is ectopically processed and activated in a ligand-dependent manner, causing progenitor-originated tumorigenesis. Our results therefore unveil a safeguard mechanism whereby retromer retrieves potentially harmful Notch receptors in a timely manner to prevent aberrant Notch activation-induced neural progenitor dedifferentiation and brain tumor formation.

We report the plasma effect to a frequency doubled probe pulse by measuring its transmitted absorption spectrum. The transmitted spectrum is attenuated after interaction with the plasma generated by an 800 nm intense femtosecond laser pulse. This effect varies with the center wavelength of the probe pulse, which is believed to be caused by the resonance absorption due to generation. This phenomenon also depends on polarization and energy of the 800 nm pulse, indicating energy transfer to the 800 nm pulse from the frequency doubled pulse. [ABSTRACT FROM AUTHOR]