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Coastal zones have intense human activity and are ecologically fragile. Assessing ecological risks in coastal zones is crucial to promoting ecological safety and sustainable development for coastal cities. However, the relationship between ecological risk assessment and distance from the coastline is indeterminate in current research. To solve this problem, this study constructs the sea–land gradient and reconstructs the landscape pattern index and landscape ecological risk index (ERI) considering the sea–land gradient paradigm. This study aims to analyze the spatial–temporal variation characteristics and effects of the sea–land gradient on landscape pattern and ecological risk in Dalian City from 2000 to 2015. The results show the following: (1) between 2000 and 2015, a significant effect of coastline on the coastal landscape pattern in Dalian is reducing landscape fragmentation. The extent of this influence gradually diminished along the sea–land gradient. The landscape aggregation of urban building sites near the sea was relatively high and gradually increased over the years; (2) in Dalian, the landscape ERI has decreased near the sea and increased near the inland year by year; (3) the dominant pattern of landscape ecological risk was characterized by a transition from high to low levels within the [0, 2.5] km zone, while a transition from low to high levels predominated within the [2.5, Max] km zone; and (4) the northern region in Dalian primarily goes from high to low risk in the buffer zone near the landside, whereas the southern area has this changing pattern in the buffer zone near the seaside.

Abstract More than 2 million years ago in East Africa, the earliest hominin stone tools evolved amidst changes in resource base, with pounding technology playing a key role in this adaptive process. Olduvai Gorge (now Oldupai) is a famed locality that remains paramount for the study of human evolution, also yielding some of the oldest battering tools in the world. However, direct evidence of the resources processed with these technologies is lacking entirely. One way to obtain this evidence is through the analysis of surviving residues. Yet, linking residues with past processing activities is not simple. In the case of plant exploitation, this link can only be established by assessing site-based reference collections inclusive of both anthropogenic and natural residues as a necessary first step and comparative starting point. In this paper, we assess microbotanical remains from rock clasts sourced at the same quarry utilized by Oldowan hominins at Oldupai Gorge. We mapped this signal and analysed it quantitatively to classify its spatial distribution objectively, extracting proxies for taxonomic identification and further comparison with freestanding soils. In addition, we used blanks to manufacture pounding tools for blind, controlled replication of plant processing. We discovered that stone blanks are in fact environmental reservoirs in which plant remains are trapped by lithobionts, preserved as hardened accretions. Tool use, on the other hand, creates residue clusters; however, their spatial distribution can be discriminated from purely natural assemblages by the georeferencing of residues and statistical analysis of resulting patterns. To conclude, we provide a protocol for best practice and a workflow that has the advantage of overcoming environmental noise, reducing the risk of false positive, delivering a firm understanding of residues as polygenic mixtures, a reliable use of controls, and most importantly, a stronger link between microbotanical remains and stone tool use.

In November 2018, a scientific scandal broke when news emerged that the world’s first gene edited babies had been born in China on the eve of the 2nd International Summit on Human Genome Editing in Hong Kong. He Jiankui had recruited a total of seven couples who were in need of fertility treatment to participate in an effort to clinically apply human embryo editing with the promise that, if successful, their future children would be protected from HIV. While He Jiankui has since been jailed for illegal medical practice and much has been written about his unethical and flawed “experiment,” in this article we suggest that the Hong Kong summit nevertheless marked the moment when human embryo editing came to be platformed. Human embryo editing brings together a complete set of new reproductive and genetic technologies into a total bio-reproductive platform shaped by socio-technical “disease free” imaginaries.

Various means of extracting road boundary from mobile laser scanning data based on vehicle trajectories have been investigated. Independent of positioning and navigation data, this study estimated the scanner ground track from the spatial distribution of the point cloud as an indicator of road location. We defined a typical edge block consisting of multiple continuous upward fluctuating points by abrupt changes in elevation, upward slope, and road horizontal slope. Subsequently, such edge blocks were searched for on both sides of the estimated track. A pseudo-mileage spacing map was constructed to reflect the variation in spacing between the track and edge blocks over distance, within which road boundary points were detected using a simple linear tracking model. Experimental results demonstrate that the ground trajectory of the extracted scanner forms a smooth and continuous string just on the road; this can serve as the basis for defining edge block and road boundary tracking algorithms. The defined edge block has been experimentally verified as highly accurate and strongly noise resistant, while the boundary tracking algorithm is simple, fast, and independent of the road boundary model used. The correct detection rate of the road boundary in two experimental data is more than 99.2%.

With the principle of metamorphic mechanism,aiming at the right- angle space problem often encountered in the cabinet arrangement,a new kind of cabinet is designed and the design plan and size calculation are given.

Al2O3/TiAl in situ composites doped with Cr and V2O5 were successfully prepared from Ti, Al, TiO2, Cr and V2O5 by hot pressing. The effect of in situ formed Al2O3 content on the phase composition, microstructure and mechanical properties of Al2O3/TiAl composites were investigated. The results show that the as-synthesized composites mainly consisted of γ-TiAl/α2-Ti3Al matrix and dispersive Al2O3 reinforcing phases. The in situ formed fine Al2O3 ceramic particles mainly disperse on the grain boundaries of TiAl, resulting in refinement of TiAl matrix, which improves the mechanical properties of the Al2O3/TiAl in situ composite. The composite with 7.54 at.% Al2O3 possesses the maximum flexural strength and fracture toughness of 335.38 MPa and 5.39 MPa m1/2, respectively. The strengthening mechanism was also discussed in detail.