Aluminum ablation by multiple femtosecond laser pulses is investigated via time-resolved shadowgraphs and scanning electron microscope (SEM) images of the ablation spot. The spatial distribution of the ejected mater...Aluminum ablation by multiple femtosecond laser pulses is investigated via time-resolved shadowgraphs and scanning electron microscope (SEM) images of the ablation spot. The spatial distribution of the ejected material and the radius of the shock wave generated during the ablation are found to vary with the increase in the number of pulses. In the initial two pulses, nearly concentric and semicircular stripes within the shock wave front are observed, unlike in subsequent pulses. Ablation by multiple femtosecond pulses exhibits different characteristics compared with the case induced by single femtosecond pulse because of the changes to the aluminum target surface induced by the preceding pulses.展开更多
A new species of Macandrewia Gray from a seamount near Yap Trench in the Western Pacific Ocean was described.Macandrewia yapensis sp.nov.is distinct from its congeners by possessing a foliate shape with contorted lame...A new species of Macandrewia Gray from a seamount near Yap Trench in the Western Pacific Ocean was described.Macandrewia yapensis sp.nov.is distinct from its congeners by possessing a foliate shape with contorted lamellae,tuberculiform terminations of desmas,and unique size of spicules.This is the third species of Macandrewia described from the Pacific Ocean.In addition a partial sequence of COI gene was obtained from the new specimen and then it submitted to GenBank.Phylogenetic tree constructed with the partial COI sequences appears to exhibit a more congruent relationship with morphological data of macandrewiid species compared to 28 S gene tree.展开更多
As of 2015,204 cases of missing and murdered Indigenous women and girls(MMIWG)remained unsolved in Canada,making it a major concern for Canadian Indigenous communities,who are still pressing for the resolution of thes...As of 2015,204 cases of missing and murdered Indigenous women and girls(MMIWG)remained unsolved in Canada,making it a major concern for Canadian Indigenous communities,who are still pressing for the resolution of these cases.In forensic anthropology,the assessment of population affinity can be useful to help identify victims.Population affinity,previously referred to as ancestry,is evaluated based on morphological analyses,which examine the size and shape of skeletal features,and metric analyses,which utilise skeletal measurements.However,morphological analyses strongly depend on an anthropologist’s experience with human variation,which makes the analyses particularly challenging to reproduce and standardise.The purpose of this study is to improve the rigour of morphological analyses by using 3D technology to quantify relevant cranial nonmetric population affinity traits.As there is currently little morphological data available for the Canadian Indigenous population,this research aims to develop a new technique that could aid in the identification of MMIWG.The study comprised a total of 87 adult female crania,including 24 of Canadian Inuit origin,50 of European descent and 13 of African descent.The samples were imaged using photogrammetry,then analysed using a 3D shape analysis in 3DS Max.Results show that this method is satisfactory in correctly evaluating population affinity with an accuracy of 87.36%(jackknifed:80.46%)and an average repeatability of 97%.Unfortunately,the small Canadian Indigenous sample size impacted the applicability of the results and further research will be required before the technique can be used to aid in the identification of MMIWG in Canada.展开更多
基金Project supported by the Science and Technology Development Fund Planning Project for the Universities of Tianjin,China(Grant No.20140902)the Natural Science Foundation of Tianjin City,China(Grant No.16JCQNJC01900)+1 种基金the National Natural Science Foundation of China(Grant Nos.51376136and 61474082)the Science and Technology Achievement Award Project for the Universities of Tianjin,China
文摘Aluminum ablation by multiple femtosecond laser pulses is investigated via time-resolved shadowgraphs and scanning electron microscope (SEM) images of the ablation spot. The spatial distribution of the ejected material and the radius of the shock wave generated during the ablation are found to vary with the increase in the number of pulses. In the initial two pulses, nearly concentric and semicircular stripes within the shock wave front are observed, unlike in subsequent pulses. Ablation by multiple femtosecond pulses exhibits different characteristics compared with the case induced by single femtosecond pulse because of the changes to the aluminum target surface induced by the preceding pulses.
基金the Science&Technology Basic Resources Investigation Program of China(No.2017FY100804)the Biological Resources Program,Chinese Academy of Sciences(No.KFJ-BRP-017-37)+1 种基金the National Key R&D Program of China(No.2018YFC0309804)the National Natural Science Foundation of China(No.41706188)。
文摘A new species of Macandrewia Gray from a seamount near Yap Trench in the Western Pacific Ocean was described.Macandrewia yapensis sp.nov.is distinct from its congeners by possessing a foliate shape with contorted lamellae,tuberculiform terminations of desmas,and unique size of spicules.This is the third species of Macandrewia described from the Pacific Ocean.In addition a partial sequence of COI gene was obtained from the new specimen and then it submitted to GenBank.Phylogenetic tree constructed with the partial COI sequences appears to exhibit a more congruent relationship with morphological data of macandrewiid species compared to 28 S gene tree.
基金supported by the Social Sciences and Humanities Research Council of Canada(SSHRC).
文摘As of 2015,204 cases of missing and murdered Indigenous women and girls(MMIWG)remained unsolved in Canada,making it a major concern for Canadian Indigenous communities,who are still pressing for the resolution of these cases.In forensic anthropology,the assessment of population affinity can be useful to help identify victims.Population affinity,previously referred to as ancestry,is evaluated based on morphological analyses,which examine the size and shape of skeletal features,and metric analyses,which utilise skeletal measurements.However,morphological analyses strongly depend on an anthropologist’s experience with human variation,which makes the analyses particularly challenging to reproduce and standardise.The purpose of this study is to improve the rigour of morphological analyses by using 3D technology to quantify relevant cranial nonmetric population affinity traits.As there is currently little morphological data available for the Canadian Indigenous population,this research aims to develop a new technique that could aid in the identification of MMIWG.The study comprised a total of 87 adult female crania,including 24 of Canadian Inuit origin,50 of European descent and 13 of African descent.The samples were imaged using photogrammetry,then analysed using a 3D shape analysis in 3DS Max.Results show that this method is satisfactory in correctly evaluating population affinity with an accuracy of 87.36%(jackknifed:80.46%)and an average repeatability of 97%.Unfortunately,the small Canadian Indigenous sample size impacted the applicability of the results and further research will be required before the technique can be used to aid in the identification of MMIWG in Canada.