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71.
《L'Anthropologie》2022,126(2):103016
This paper presents the results of the “Archaeological Map in Northern Morocco” project, which has been carried out by researchers from the University of Cadiz, University of Abdelmalek Essaadi and INSAP of Rabat. Four seasons of archaeological survey have taken place in the Tetouan region as well as excavations in the Cave El Hafa and the rock-shelter of Marsa. This study includes geomorphological data and a petrographic study to pinpoint of the origins of raw material used by the different human groups that duelled in the area. Lastly, this paper presents settlement patterns of the studied groups, most importantly, this is an updated study of the relevant occupations that correspond to Palaeolithic hunter-gatherer societies, Neolithic tribal societies and also, of human settlements associated to Recent Prehistory stages.  相似文献   
72.
黄土丘陵区坡耕地与撂荒地土壤水分对降雨的响应特征   总被引:3,自引:0,他引:3  
为了揭示黄土丘陵区不同土地覆被方式下土壤含水量对不同强度降雨的响应过程,选取山西省冯家沟小流域农耕地和撂荒地为研究对象,基于2019年4—10月降雨和土壤含水量以小时为单位的观测数据,分析了土壤含水量对不同强度降雨的响应规律。结果表明:(1)小雨、中雨、大雨和暴雨对土层的影响深度分别为20、20、60 cm和60 cm,研究区降雨最主要的形式—小雨对土壤水分的补给作用较小。(2)各强度降雨过程中,除0—10 cm土层外,农耕地土壤含水量均大于撂荒地,且大雨条件下农耕地各土层土壤含水量变化较显著,而撂荒地仅0—10 cm和10—20 cm土层土壤含水量有所增加。(3)不同土层土壤含水量对降雨的响应不同,表层响应相对明显而深层相对减弱;农耕地土壤平均含水量最大值出现在50—60 cm土层,而撂荒地出现在30—40 cm土层。(4)本地区农耕地土壤含水量高于撂荒地,表明在该地区适当的作物种植有较好的储存土壤水分的作用。本研究的结果对地区水资源的高效利用和水土流失防控提供了一定的科学依据。  相似文献   
73.
Three A–π–A or D–π–D perylene diimide ( PDI ) derivatives with varied groups on π-conjugate were synthesized and characterized. The photophysical properties of these compounds were systematically studied by spectral experiments and density functional theory calculations. All compounds displayed intense absorption bands at 300–800 nm wavelengths. However, diverse groups on the π-conjugate influenced the UV–vis absorption. Electron-withdrawing groups on PDI-2 caused a slight red shift at the 350–400 nm wavelength and a blue shift after 400 nm wavelength. At the same time, the electron-donating substituents on PDI-3 caused an obvious red shift of this band. These PDI derivatives exhibited emission in solution at room temperature (λem = 500–850 nm). The quantum yield of PDI-3 decreased, while the electron-donating substituents were introduced to the π-conjugated motifs. However, the quantum yield of PDI-2 increased when electron-withdrawing substituents were introduced to the π-conjugated motifs. In addition, PDI-1 and PDI-2 exhibited broad triplet transient absorption in the visible region. These photophysical properties could help us to understand the relationship between structure and photophysical properties of perylene diimide derivatives and exploit more original perylene diimide-based optical functional materials.  相似文献   
74.
《L'Anthropologie》2019,123(2):403-422
The Upper Palaeolithic site of Yudinovo is one of the reference sites, located in the Desna River Basin. Multidisciplinary field studies, organized by the Desna mission (MAE RAS) and conducted between 2004 and 2016, have changed the vision existed so far on the structure and character of the Yudinovo site as well as on the duration of its occupations. The researchers found an ancient ford used by mammoths and other big mammals to cross the river, and a water source was one of the main factors in explaining the location of the Yudinovo site. The site has been occupied in a cyclical way for stays of varied duration. It was frequented by Prehistoric Men during the different seasons, and periods of occupation were apparently of different duration. The stratigraphy of the Yudinovo site reveals two major episodes in the evolution of the site. The dating of the lower archaeological layer dates back to 15,000–13,500 BC. J.C., while the upper layer is attributed to the period of 12,500–12,000 BC. The lower layer, which was formed during the major episode of occupation of the site, is rather thin and shows the complex stratigraphic structure. Various areas of activities, evacuation structures, storage areas with mammoth bones are discovered. Some elements of the lower archaeological layer are perfectly correlated with different episodes of sporadic occupation.  相似文献   
75.
Collagen is one of the most abundant and important proteins in the human body. Human collagen type III (hCOL3A1) belongs to the fibril-forming collagens and is widely distributed in extensible connective tissue like skin, internal organs, or the vascular system. It plays key roles in wound healing, collagen fibrillogenesis, and normal cardiovascular development in human. The charged residues are considered to be an important characteristic of hCOL3A1, especially for collagen binding and recognition. Here we found that a triple helix fragment of hCOL3A1, Gly489-Gly510, contained multiple charged residues, as well as representative Glu-Lys-Gly and Glu-Arg-Gly charged triplets. We solved the crystal structure of this new fragment to a high-resolution of 1.50?Å and identified some important conformations of this new triple-helix region, including strong hydrogen bonds in interchain and interhelical interactions in addition to obvious flexible bending for the triple helix. We also found that the synthetic collagen peptides around this region exhibited potent activities through integrin-mediated peptide-membrane interaction. We then developed a method to produce a recombinant protein consisting of 16 tandem repeats of the triple-helix fragment of hCOL3A1 with strong activity without cytotoxicity. These results provide a strong base for further functional studies of human collagen type III and the method developed in this study can be applied to produce hCOL3A1-derived proteins or other tandem-repeat proteins with membrane adhesion activity.  相似文献   
76.
目的:调查我国西北地区康复治疗师的现状,为规范康复治疗师培养的改革提供依据。方法:采用抽样调查的方法,向西北五个省区部分康复医疗单位发放调查问卷共200份,由单位负责人填写,调查内容包括该单位康复治疗师的数量、专业、学历、从业时间、职称、持证情况和对培训的需求情况等,填写完成后进行数据统计分析。结果:康复治疗师中从事神经康复方向的治疗师比例最高,约为45.04%。大部分的治疗师从业时间都在5年以内,从业时间大于5年的比例只占13.68%。77.60%的治疗师为医学相关专业毕业,多数治疗师为本科以下学历,硕士和博士学历仅占0.48%,而获得康复治疗师资格证书的人员比例仅为39.35%。治疗师的职称也大多为初、中级(92.49%),高级职称治疗师仅占7.51%,78.81%的治疗师希望得到高水平的培训或进修。结论:西北地区康复治疗师整体从业时间较短,学历较低,缺乏高职称的治疗师,康复治疗师人才队伍培养体系亟待改善。  相似文献   
77.
DNA barcoding using a partial region (648 bp) of the cytochrome c oxidase I (COI) gene is a powerful tool for species identification and has revealed many cryptic species in various animal taxa. In birds, cryptic species are likely to occur in insular regions like the Japanese Archipelago due to the prevention of gene flow by sea barriers. Using COI sequences of 234 of the 251 Japanese‐breeding bird species, we established a DNA barcoding library for species identification and estimated the number of cryptic species candidates. A total of 226 species (96.6%) had unique COI sequences with large genetic divergence among the closest species based on neighbour‐joining clusters, genetic distance criterion and diagnostic substitutions. Eleven cryptic species candidates were detected, with distinct intraspecific deep genetic divergences, nine lineages of which were geographically separated by islands and straits within the Japanese Archipelago. To identify Japan‐specific cryptic species from trans‐Paleartic birds, we investigated the genetic structure of 142 shared species over an extended region covering Japan and Eurasia; 19 of these species formed two or more clades with high bootstrap values. Excluding six duplicated species from the total of 11 species within the Japanese Archipelago and 19 trans‐Paleartic species, we identified 24 species that were cryptic species candidates within and surrounding the Japanese Archipelago. Repeated sea level changes during the glacial and interglacial periods may be responsible for the deep genetic divergences of Japanese birds in this insular region, which has led to inconsistencies in traditional taxonomies based on morphology.  相似文献   
78.
The genus Curcuma L. is commonly used as spices, medicines, dyes and ornamentals. Owing to its economic significance and lack of clear‐cut morphological differences between species, this genus is an ideal case for developing DNA barcodes. In this study, four chloroplast DNA regions (matK, rbcL, trnH‐psbA and trnL‐F) and one nuclear region (ITS2) were generated for 44 Curcuma species and five species from closely related genera, represented by 96 samples. PCR amplification success rate, intra‐ and inter‐specific genetic distance variation and the correct identification percentage were taken into account to assess candidate barcode regions. PCR and sequence success rate were high in matK (89.7%), rbcL (100%), trnH‐psbA (100%), trnL‐F (95.7%) and ITS2 (82.6%) regions. The results further showed that four candidate chloroplast barcoding regions (matK, rbcL, trnH‐psbA and trnL‐F) yield no barcode gaps, indicating that the genus Curcuma represents a challenging group for DNA barcoding. The ITS2 region presented large interspecific variation and provided the highest correct identification rates (46.7%) based on BLASTClust method among the five regions. However, the ITS2 only provided 7.9% based on NJ tree method. An increase in discriminatory power needs the development of more variable markers.  相似文献   
79.
目的:探讨人Daintain 基因5''调控区的序列特征。方法:利用在线软件BLAST、Neural Network Promoter Prediction、Promoter 2.0、Promoter SCAN、EMBOSS、CpG Island Searcher 和TF SEARCH预测人Daintain 基因启动子区域、CpG 岛分布和转录因子结 合位点。结果:人Daintain 基因5''调控区存在1 个CAAT盒。Daintain 基因可能存在6 个启动子位点,CpG岛可能位于216 bp 区 间( 23 ~ 238 bp)。评分85 分以上时,该序列存在251 个可能的转录因子结合位点;评分90 分以上时,该序列存在70 个可能的转 录因子结合位点;评分95 分以上时,该序列存在16个可能的转录因子结合位点;评分100 分以上时,该序列存在7 个可能的转 录因子结合位点;这些结合的转录因子基本是与免疫细胞增殖或性别发生有关。结论:人Daintain 基因5''调控区的生物信息学研 究表明其转录受甲基化和多种转录因子的调控,为研究Daintain 基因启动子的功能提供理论基础。  相似文献   
80.
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