Habitat quality assessment and multi-scenario prediction of the Gansu-Qinghai section of the Yellow River Basin based on the FLUS-InVEST model

Research on the impact of land use change on regional habitat quality, in various future scenarios, can effectively aid planning and decision-making for sustainable development at a regional level. The study conducted its research in the Gansu-Qinghai Yellow River section and used ArcGIS and a land use transfer matrix to analyze the spatiotemporal pattern of land use and land cover changes. The study assessed the changes in habitat quality in the Gansu-Qinghai Yellow River region between 1990 and 2020, using the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model, by evaluating the gains and losses. Simultaneously, 15 elements of the natural economy were chosen and examined for their temporal and spatial impact on habitat quality using the random forest model and spatially weighted regression model. To forecast land use changes in the Gansu-Qinghai Yellow River section for 2030, the Future Land Use Simulation Model (FLUS) model was utilized and a series of four scenarios (cultivated land protection scenario, ecological protection scenario, natural development scenario, and rapid development scenario) were employed. The research results indicate that over 70% of the Gansu-Qinghai Yellow River is occupied by grasslands, and only a small portion of the area, about 0.22%, is developed for construction purposes. The quality of the habitat in the Gansu-Qinghai Yellow River had a minor drop between 1990 and 2020, followed by an improvement. Habitat quality changes are primarily attributed to improvements, with variations across different areas, i.e., enhanced in the east and reduced in the central and western parts. The habitat quality of the Gansu-Qinghai Yellow River has improved in all four scenarios compared to 2020, as evidenced by the decrease in low-value habitats and increase in high-value areas. The ecological protection scenario has the highest average habitat quality value. These research results can be used to support policy development and ecological restoration initiatives in the Gansu-Qinghai Yellow River

Quasi-Two-Dimensional Fermi Surface and Heavy Quasiparticles in CeRh2As2

The recent discovery of multiple superconducting phases in CeRh2As2 has attracted considerable interest. These rich phases are thought to be related to the locally noncentrosymmetric crystal structure, although the possible role of a quadrupole density wave preceding the superconductivity remains an open question. While measurements of physical properties imply that the Ce 4f electrons could play an essential role, the momentum-resolved electronic structure remains hitherto unreported, hindering an in-depth understanding of the underlying physics. Here, we report a high-resolution angle-resolved photoemission study of CeRh2As2. Our results reveal fine splittings of conduction bands, which are directly related to the locally noncentrosymmetric structure, as well as a quasi-two-dimensional Fermi surface, implying weak interlayer hopping and possible nesting instabilities. Our experiments also uncover the fine structures and pronounced temperature evolution of the Kondo peak, demonstrating strong Kondo effect facilitated by excited crystal electric field states. Our results unveil the salient electronic features arising from the interplay between the crystal structure and strong electron correlation, providing spectroscopic insight for understanding the heavy fermion physics and unconventional quadrupole density wave in this enigmatic compound

Association of bone morphogenetic protein-2 gene polymorphisms with susceptibility to ossification of the posterior longitudinal ligament of the spine and its severity in Chinese patients

A case–control study was conducted to examine the association between two single nucleotide polymorphisms (SNPs) in exon 2 of the bone morphogenetic protein-2 gene (BMP-2) and ossification of the posterior longitudinal ligament (OPLL), and to investigate whether SNPs of the Ser37Ala (T/G) and the Ser87Ser (A/G) in the BMP-2 gene are associated with genetic susceptibility to OPLL and its severity in Chinese subjects. The Ser87Ser (A/G) SNP has been implicated in bone mineral density (BMD) and increases the risk of OA in women. The Ser37Ala (T/G) SNP is associated with BMD and the rate of bone loss in osteoporosis and osteoporosis fractures. A total of 57 OPLL patients and 135 non-OPLL controls were studied. Radiographs of the cervical spine were analyzed to determine the presence and the severity of OPLL. The association of two SNPs with the occurrence and the extent of OPLL were statistically evaluated. There was a significant association between the Ser37Ala (T/G) polymorphism and the occurrence of OPLL in the cervical spine. However, no significant association was found between the Ser37Ala (T/G) polymorphism and the more number of ossified cervical vertebrae in OPLL patients. There was a significant association between the Ser87Ser (A/G) polymorphism and the more number of ossified cervical vertebrae in OPLL patients. However, there was no statistical difference between the Ser87Ser (A/G) SNP and the occurrence of OPLL in the cervical spine. In addition, the Ser87Ser (A/G) polymorphism in male patients and in female patients showed no statistical difference between cases and controls. The present results demonstrate that BMP-2 Gene is not only a factor associated with the occurrence of OPLL, but also a factor related to more extensive OPLL. The “G” allele in the Ser37Ala (T/G) polymorphism is associated with the occurrence of OPLL, but not more extensive OPLL in the cervical spine. The “G” allele in the Ser87Ser (A/G) polymorphism promotes the extent of OPLL, whereas the “A” allele in the Ser87Ser (A/G) polymorphism restricts ectopic ossification in the cervical spine at least in Chinese subjects

Identification of Novel phoP-phoQ Regulated Genes that Contribute to Polymyxin B Tolerance in Pseudomonas aeruginosa

Polymyxin B and E (colistin) are the last resorts to treat multidrug-resistant Gram-negative pathogens. Pseudomonas aeruginosa is intrinsically resistant to a variety of antibiotics. The PhoP-PhoQ two-component regulatory system contributes to the resistance to polymyxins by regulating an arnBCADTEF-pmrE operon that encodes lipopolysaccharide modification enzymes. To identify additional PhoP-regulated genes that contribute to the tolerance to polymyxin B, we performed a chromatin immunoprecipitation sequencing (ChIP-Seq) assay and found novel PhoP binding sites on the chromosome. We further verified that PhoP directly controls the expression of PA14_46900, PA14_50740 and PA14_52340, and the operons of PA14_11970-PA14_11960 and PA14_52350-PA14_52370. Our results demonstrated that mutation of PA14_46900 increased the bacterial binding and susceptibility to polymyxin B. Meanwhile, mutation of PA14_11960 (papP), PA14_11970 (mpl), PA14_50740 (slyB), PA14_52350 (ppgS), and PA14_52370 (ppgH) reduced the bacterial survival rates and increased ethidium bromide influx under polymyxin B or Sodium dodecyl sulfate (SDS) treatment, indicating roles of these genes in maintaining membrane integrity in response to the stresses. By 1-N-phenylnaphthylamine (NPN) and propidium iodide (PI) staining assay, we found that papP and slyB are involved in maintaining outer membrane integrity, and mpl and ppgS-ppgH are involved in maintaining inner membrane integrity. Overall, our results reveal novel PhoP-PhoQ regulated genes that contribute to polymyxin B tolerance

Coordinated State Analysis and Differential Regulation of Territorial Spatial Functions in Underdeveloped Regions: A Case Study of Gansu Province, China

The coordinated development of territorial spatial functions is the main manifestation of the sustainable utilization of territorial resources. Identifying spatial functions and their coordinated relationship has become an important guarantee for regional coordinated development, and is of great significance to the construction of a sustainable land development and protection pattern. This study constructs a classification and function scoring system for Production-Living-Ecological Spaces (PLES) by using land-use data from Gansu Province in 2000 and 2020, and revises the spatial functions of the land to supplement the deficiencies of existing related researches by combining socio-economic data (GDP, population density) and ecosystem service value data. In the aforementioned works, the Mechanical Equilibrium Model in physics is referenced to explore the coordinated state among territorial spatial functions. The results show that the high-value areas of production function are mainly distributed in the eastern and central areas of the Loess Plateau, with a strip-like distribution in the Hexi Corridor. The high-value areas of living function are consistent with that in the center of the city. The distribution of high-value areas of ecological function is in line with the topographic distribution pattern of mountainous areas in Gansu Province. The distribution pattern of the coordinated state of land space function in Gansu Province is relatively stable from 2000 to 2020. Simultaneously, the functional dominant area and the promotion area are identified according to the deviation of the coordinated degree of production-living-ecological function. After clarifying the functional characteristics of each county, the author proposes a differentiated regulation strategy of territorial spatial function

A Layer-Dependent Analytical Model for Printability Assessment of Additive Manufacturing Copper/Steel Multi-Material Components by Directed Energy Deposition

Copper/steel bimetal, one of the most popular and typical multi-material components (MMC), processes excellent comprehensive properties with the high strength of steel and the high thermal conductivity of copper alloy. Additive manufacturing (AM) technology is characterized by layer-wise fabrication, and thus is especially suitable for fabricating MMC. However, considering both the great difference in thermophysical properties between copper and steel and the layer-based fabrication character of the AM process, the optimal processing parameters will vary throughout the deposition process. In this paper, we propose an analytical calculation model to predict the layer-dependent processing parameters when fabricating the 07Cr15Ni5 steel on the CuCr substrate at the fixed layer thickness (0.3 mm) and hatching space (0.3 mm). Specifically, the changes in effective thermal conductivity and specific heat capacity with the layer number, as well as the absorption rate and catchment efficiency with the processing parameters are considered. The parameter maps predicted by the model have good agreement with the experimental results. The proposed analytical model provides new guidance to determine the processing windows for novel multi-material components, especially for the multi-materials whose physical properties are significantly different

A Layer-Dependent Analytical Model for Printability Assessment of Additive Manufacturing Copper/Steel Multi-Material Components by Directed Energy Deposition

Copper/steel bimetal, one of the most popular and typical multi-material components (MMC), processes excellent comprehensive properties with the high strength of steel and the high thermal conductivity of copper alloy. Additive manufacturing (AM) technology is characterized by layer-wise fabrication, and thus is especially suitable for fabricating MMC. However, considering both the great difference in thermophysical properties between copper and steel and the layer-based fabrication character of the AM process, the optimal processing parameters will vary throughout the deposition process. In this paper, we propose an analytical calculation model to predict the layer-dependent processing parameters when fabricating the 07Cr15Ni5 steel on the CuCr substrate at the fixed layer thickness (0.3 mm) and hatching space (0.3 mm). Specifically, the changes in effective thermal conductivity and specific heat capacity with the layer number, as well as the absorption rate and catchment efficiency with the processing parameters are considered. The parameter maps predicted by the model have good agreement with the experimental results. The proposed analytical model provides new guidance to determine the processing windows for novel multi-material components, especially for the multi-materials whose physical properties are significantly different

Coordinated State Analysis and Differential Regulation of Territorial Spatial Functions in Underdeveloped Regions: A Case Study of Gansu Province, China

The coordinated development of territorial spatial functions is the main manifestation of the sustainable utilization of territorial resources. Identifying spatial functions and their coordinated relationship has become an important guarantee for regional coordinated development, and is of great significance to the construction of a sustainable land development and protection pattern. This study constructs a classification and function scoring system for Production-Living-Ecological Spaces (PLES) by using land-use data from Gansu Province in 2000 and 2020, and revises the spatial functions of the land to supplement the deficiencies of existing related researches by combining socio-economic data (GDP, population density) and ecosystem service value data. In the aforementioned works, the Mechanical Equilibrium Model in physics is referenced to explore the coordinated state among territorial spatial functions. The results show that the high-value areas of production function are mainly distributed in the eastern and central areas of the Loess Plateau, with a strip-like distribution in the Hexi Corridor. The high-value areas of living function are consistent with that in the center of the city. The distribution of high-value areas of ecological function is in line with the topographic distribution pattern of mountainous areas in Gansu Province. The distribution pattern of the coordinated state of land space function in Gansu Province is relatively stable from 2000 to 2020. Simultaneously, the functional dominant area and the promotion area are identified according to the deviation of the coordinated degree of production-living-ecological function. After clarifying the functional characteristics of each county, the author proposes a differentiated regulation strategy of territorial spatial function

A Time-Variant Reliability Model for Copper Bending Pipe under Seawater-Active Corrosion Based on the Stochastic Degradation Process

In the degradation process, the randomness and multiplicity of variables are difficult to describe by mathematical models. However, they are common in engineering and cannot be neglected, so it is necessary to study this issue in depth. In this paper, the copper bending pipe in seawater piping systems is taken as the analysis object, and the time-variant reliability is calculated by solving the interference of limit strength and maximum stress. We did degradation experiments and tensile experiments on copper material, and obtained the limit strength at each time. In addition, degradation experiments on copper bending pipe were done and the thickness at each time has been obtained, then the response of maximum stress was calculated by simulation. Further, with the help of one kind of Monte Carlo method we propose, the time-variant reliability of copper bending pipe was calculated based on the stochastic degradation process and interference theory. Compared with traditional methods and verified by maintenance records, the results show that the time-variant reliability model based on the stochastic degradation process proposed in this paper has better applicability in the reliability analysis, and it can be more convenient and accurate to predict the replacement cycle of copper bending pipe under seawater-active corrosion

KLPPS: A k-Anonymous Location Privacy Protection Scheme via Dummies and Stackelberg Game

Protecting location privacy has become an irreversible trend; some problems also come such as system structures adopted by location privacy protection schemes suffer from single point of failure or the mobile device performance bottlenecks, and these schemes cannot resist single-point attacks and inference attacks and achieve a tradeoff between privacy level and service quality. To solve these problems, we propose a k-anonymous location privacy protection scheme via dummies and Stackelberg game. First, we analyze the merits and drawbacks of the existing location privacy preservation system architecture and propose a semitrusted third party-based location privacy preservation architecture. Next, taking into account both location semantic diversity, physical dispersion, and query probability, etc., we design a dummy location selection algorithm based on location semantics and physical distance, which can protect users’ privacy against single-point attack. And then, we propose a location anonymous optimization method based on Stackelberg game to improve the algorithm. Specifically, we formalize the mutual optimization of user-adversary objectives by using the framework of Stackelberg game to find an optimal dummy location set. The optimal dummy location set can resist single-point attacks and inference attacks while effectively balancing service quality and location privacy. Finally, we provide exhaustive simulation evaluation for the proposed scheme compared with existing schemes in multiple aspects, and the results show that the proposed scheme can effectively resist the single-point attack and inference attack while balancing the service quality and location privacy