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Internal Microanatomy and Zoological Affinity of the Early Cambrian Olivooides 被引量:6
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作者 Han Jian LI Guoxiang +10 位作者 KUBOTA Shin OU Qiang TOSHINO Sho WANG Xing YANG Xiaoguang UESUGI Kentaro MASATO Hoshino SASAKI Osamu KANO Harumasa SATO Tomohiko KOMIYA Tsuyoshi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期38-65,共28页
The early Cambrian pentamerous microfossil Olivooides/Punctatus in South China, which is characterized by a diagnostic stellate tubular apex, has been well-known for its almost complete development sequence that can b... The early Cambrian pentamerous microfossil Olivooides/Punctatus in South China, which is characterized by a diagnostic stellate tubular apex, has been well-known for its almost complete development sequence that can be confidently traced from embryos and hatched juveniles, to conical adults. However, its zoological affinity remains highly controversial. Here we describe the internal microanatomic structures of the soft-body inside the peridermal theca of Olivooides multisulcatus Qian, 1977, including interradial pairs of tentacles, adradial and perradial frenula, perradial oral marginal lappets and twins of perradial gastric saccule-like humps as well as a circular velarium with striated coronal muscles. Particularly, one specimen shows bifurcated velarial canals along the bell aperture. Both the components of the soft-body and the external theca (or cyst) are arranged in perfect pentaradial symmetry. These characteristics are more compatible with those of living cubomedusans and co-occurring Cambrian athecate embryonic cubozoans. Concerning the presence of peridermal theca, Olivooides most likely represents an extinct thecate stem-group cubomedusae but devoid of both perradial eyes and specialized pedalia. The well-grown soft body inside the peridermal tube displays a set of mixed features of both polyp and medusa. 展开更多
关键词 Embryos PERIDERM CNIDARIANS cubozoan early Cambrian Kuanchuanpu Formation
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Redox history of the Three Gorges region during the Ediacaran and Early Cambrian as indicated by the Fe isotope 被引量:2
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作者 Yusuke Sawaki Miyuki Tahata +3 位作者 Tsuyoshi Komiya Takafumi Hirata Jian Han Degan Shu 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第1期155-172,共18页
The Ediacaran-Cambrian transition is characterized by numerous events such as the emergence of large multi-cellular metazoans and surface environmental disturbances.Based on geological evidence,it has been proposed th... The Ediacaran-Cambrian transition is characterized by numerous events such as the emergence of large multi-cellular metazoans and surface environmental disturbances.Based on geological evidence,it has been proposed that this transition coincided with the increase in the atmospheric oxygen level that was key to the evolution of life.Even though ancient redox conditions can be inferred from the composition of sedimentary iron mineral species,this method is not necessarily applicable to all rocks.In the Earth system,the cycling of iron is of considerable interest owing to its sensitivity to redox conditions.Information regarding the paleo-oceanic iron cycle is revealed in the iron isotopic composition of ironbearing minerals.Unfortunately,only limited iron isotopic data exists for Ediacaran-to Cambrianperiod oceans.To circumvent this deficiency,we drilled a fossiliferous Ediacaran to Early Cambrian sedimentary succession in the Three Gorges region,South China.We analyzed the iron isotope ratios(δ^(56/54)Fe)of pyrite grains in the drill cores using laser ablation multi collector inductively coupled plasma mass spectrometry.The results demonstrate large variations inδ^(56/54)Fe,from-1.6 to 1.6‰,and positive iron isotope ratios are observed in many successions.The presence of positiveδ^(56/54)Fe in pyrite indicates that the ferrous iron in the seawater was partially oxidized,suggesting that seawater at Three Gorges was ferruginous during the Ediacaran and Early Cambrian periods.However,aggregated pyrite grains in organic carbon-rich black shales at Member 4 of the Doushantuo Formation and the base of the Shuijingtuo Formation yield near-zeroδ^(56/54)Fe values;this suggests that the ocean was transiently dominated by sulfidic conditions during these periods.Notably negativeδ^(56/54)Fe values,lower than-1‰,can be interpreted as a signature of DIR.The DIR also might contribute in part to the re-mineralization of organic matter during the largest negative carbon isotope anomaly in the Ediacaran. 展开更多
关键词 δ56/54Fe PYRITE EDIACARAN CAMBRIAN Three Gorges
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Modulatory Effect of Motivation on the Association of Trait Anxiety and Cognitive Performance: A Pupillometric Study 被引量:1
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作者 Takatoshi Hoshino Yoshihiko Tanno 《Journal of Behavioral and Brain Science》 2017年第7期273-286,共14页
The attentional control theory (ACT) proposes that trait anxiety disrupts functional efficiency of executive control of attention relating to working memory system such as shifting. ACT also emphasizes the modulatory ... The attentional control theory (ACT) proposes that trait anxiety disrupts functional efficiency of executive control of attention relating to working memory system such as shifting. ACT also emphasizes the modulatory role of motivation in anxiety on cognitive task performance. The present study investigated the association of trait anxiety-related inefficiencies in attentional shift and working memory performance in conjunction with the level of motivation. A variation of complex span paradigm is designed to systematically manipulate the time constraint on shifting attentional focus back and forth between working memory contents and processing task was used in this study. In the experiment, participants high and low in trait anxiety were allocated either high or low motivation induction conditions, and performed a series of complex span tasks. They also completed a state anxiety measure before and after the experimental task. Motivational states were assessed by the pupil dilation, which is known to reflect the amount of cognitive effort invested on the task at hand. Results showed that, only in low motivation condition, high trait-anxious individuals exhibited greater difficulty, relative to those low in trait anxiety, in maintaining working memory contents as the task demand increased. State anxiety showed no relation to working memory performance regardless of the level of motivation and task demands. Pupillary responses revealed that, in high motivational state, high trait-anxious individuals invested more effort than those low in trait anxiety when the task demand was low, F(1, 132) = 6.65, p = 0.0110, to moderate, F(1, 132) = 8.441, p = 0.00043. In accordance with ACT, these findings suggest that motivation can modulate the association between trait anxiety and cognitive performance along with the levels of task demand. Clinical implication is briefly discussed. 展开更多
关键词 TRAIT ANXIETY MOTIVATION Working Memory Attentional Control Theory (ACT) PUPILLOMETRY
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Neurobehavioral and Hemodynamic Evaluation of Cognitive Shifting in Children with Autism Spectrum Disorder 被引量:1
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作者 Akira Yasumura Naomi Kokubo +5 位作者 Hisako Yamamoto Yukiko Yasumura Yusuke Moriguchi Eiji Nakagawa Masumi Inagaki Kazuo Hiraki 《Journal of Behavioral and Brain Science》 2012年第4期463-470,共8页
The restrictive, stereotyped behavior in autism spectrum disorder (ASD) is considered to be related to deficits in execu- tive function. In particular, cognitive shifting in executive function is deeply related to ste... The restrictive, stereotyped behavior in autism spectrum disorder (ASD) is considered to be related to deficits in execu- tive function. In particular, cognitive shifting in executive function is deeply related to stereotyped behavior in ASD. Previous investigations have clarified that the lateral prefrontal cortex is involved in cognitive shifting when flexible changes in attention were needed. However, a few studies have revealed a direct association between cognitive shifting tasks and lateral prefrontal cortex activity in children with ASD. We examined cognitive shifting in 7- to 12-year-old children with ASD and typically developing children using the dimensional change card sort task. In addition, using near-infrared spectroscopy, we examined prefrontal brain activity in conjunction with cognitive shifting. The autistic children provided fewer correct answers and slower reaction times in the task than typically developing children. Fur- thermore, the autistic children displayed a decline in right lateral prefrontal cortex activity during the task compared with typically developing children. In addition, a negative correlation was observed between the severity of autism and brain activity during the task. These results suggest that the activity and physiological indices used in this study may be useful for identifying the symptoms of ASD and discriminating ASD from other disabilities. 展开更多
关键词 Autism SPECTRUM DISORDER Executive FUNCTION COGNITIVE SHIFTING Frontal Lobe FUNCTION Near-Infrared Spectroscopy
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Growth, Duplication and Lateral Mutual Compressive Deformation of Akouemma hemisphaeria on the Seafloor of Okondja Basin at 2.2 Ga (Gabon) 被引量:1
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作者 Ambroise Edou-Minko Mathieu Moussavou +13 位作者 Tomohiko Sato Yusuke Sawaki Simplice Ndong Ondo Richard Maire Guillaume Fleury Michel Mbina Mounguengui Anders Kaestner Richard Ortega Stéphane Roudeau Asuncion Carmona Makaya Mvoubou Benjamin Musavu Moussavou Osamu Sasaki Shigenori Maruyama 《International Journal of Geosciences》 2017年第9期1172-1191,共20页
A colony of macro-fossils Akouemma hemisphaeria has been described in the Paleoproterozoic sedimentary basin of Okondja, Gabon. These fossils are classified into two groups according to their spheroidal or elongated f... A colony of macro-fossils Akouemma hemisphaeria has been described in the Paleoproterozoic sedimentary basin of Okondja, Gabon. These fossils are classified into two groups according to their spheroidal or elongated forms. The spheroidal shapes are similar, have a tripartite structure with two hemispheres and a median disc and gradually pass to the elongated forms. These elongated forms have a pronounced bipartite tendency to two “hemispheres” separated by a median surface, and often have several ovoid “pieces” attached. The elongated specimens show both lateral growth marks and signs of fission. Growth marks are characterized by unidirectional homogeneous side elongations and lateral bud-like protuberances. The signs of fission are marked by circular furrows perpendicular to the direction of elongation, called “constriction furrows” with varying depths depending on the degree of fission of the specimen and internal vertical “division planes”. All of these ovoid and elongated specimens have undergone significant initial deformations due mainly to mutual lateral compressions in tabular beds. The Akouemma hemisphaeria macro-organisms, which were primitive probably sessile organisms, lived on the seafloor. They provide the oldest known record of macro-organisms on Earth having vegetative growth and asexual reproduction by budding, lateral elongation and fission. Their mutual lateral deformations would result from their growth. 展开更多
关键词 PALEOPROTEROZOIC Francevillian Group Okondja BASIN Akouemma hemisphaeria GROWTH DUPLICATION
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Mssbauer and XRD characterization of contaminated sediments by coal mining drainage in Neath Canal, South Wales, UK
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作者 Guodong ZHENG Akihito Kuno +5 位作者 Talib Abdulameer Mahdi David J. Evans Masaaki Miyahara Yoshio Takahashi Motoyuki Matsuo Hiroshi Shimizu 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期137-138,共2页
关键词 矿山酸性排水 氧化铁 沉积物 重金属 环境污染
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Comparison of the Biological Activity and Constituents in Japanese Ambers
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作者 Eisaku Shimizu Nozomu Shimoda +2 位作者 Tetsuaki Kawamura Naomi Ueda Ken-ichi Kimura 《Advances in Biological Chemistry》 2020年第3期99-112,共14页
<span style="font-family:Verdana;">Backgrou</span><span style="font-family:Verdana;">nd/Aim: Kuji amber is an interesting natural source for drug discovery</span><span>... <span style="font-family:Verdana;">Backgrou</span><span style="font-family:Verdana;">nd/Aim: Kuji amber is an interesting natural source for drug discovery</span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">because a new anti-allergic compound, named kujigamberol and several new compounds have been isolatated from it. It was important to evaluate the yield, biological activities and constituents of each methanol extract</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">of Kuji, Iwaki, Choshi, Mizunami and Ube ambers in Japan in order to establish if additional new compounds could be identified in these ambers. Materia</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">ls and </span><span style="font-family:Verdana;">Method: Biological activities of each extract were evaluated using growth-restoring </span><span style="font-family:Verdana;">activity of the mutant yeast strain involving Ca</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;">-signal transduction and inhibi</span><span style="font-family:Verdana;">tion activity of degranulation in rat basophilic leukemia (RBL)-2H3 cells. Constituents</span><span style="font-family:Verdana;"> of each extract were analyzed by high performance liquid chromatography (HPLC). Results: All ambers except Ube amber have growth-restoring activity against the mutant yeast. Both Kuji and Iwaki ambers inhibited the degranulation of RBL-2H3 cells induced by the calcium ionophore A23187 in a dose dependent manner. The main biologically active compound in Kuji amber, kujigamberol, was also isolated from Iwaki amber and analyzed by mass spectrometry (MS) and nuclear magnetic resonance (NMR). Conclusion: Kuji and Iwaki ambers appeared to have the same origin. Choshi, Mizunami, and Ube ambers are valuable sources for biologically active compounds which are different from those of Kuji amber.</span></span></span></span> 展开更多
关键词 Japanese Ambers Kujigamberol Growth Restoration of a Mutant Yeast Inhibition of Degranulation RBL-2H3 Cells
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A prolonged granitoid formation in Saglek Block,Labrador:Zonal growth and crustal reworking of continental crust in the Eoarchean
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作者 Tsuyoshi Komiya Shinji Yamamoto +10 位作者 Shogo Aoki Keiko Koshida Masanori Shimojo Yusuke Sawaki Kazumasa Aoki Shuhei Sakata Takaomi D.Yokoyama Kenshi Maki Akira Ishikawa Takafumi Hirata Kenneth D.Collerson 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第2期355-385,共31页
The Archean continental crusts account for ca.20% of the present volume,but the thermal history of the Earths' mantle suggests much more continental crusts were formed in the early Archean.Because the Archean contine... The Archean continental crusts account for ca.20% of the present volume,but the thermal history of the Earths' mantle suggests much more continental crusts were formed in the early Archean.Because the Archean continental crust underwent severe metamorphism,it is important to avoid influence by the later thermal events.We carried out a comprehensive geochronological work of Cathodoluminescence(CL) observation and U-Pb dating of zircons from orthogneisses and supracrustal rocks over the Saglek Block to obtain their protolith ages.The zircons were classified into three domains of core,mantle and rims,and the cores were further classified into three groups of inherited,altered and zoned cores based on the zonation on the CL images.We estimated the protolith ages from Pb-Pb ages of the zoned-cores of zircons with low U contents.We made a detailed sketch of a small outcrop in St.John's Harbour South(SJHS) area,and classified the orthogneisses and mafic enclaves into seven generations based on the geologic occurrence.The first and second generations comprise mafic rocks and lack magmatic zircons.We conducted CL imaging and U-Pb dating of zircons from the third,sixth and seventh generation of the orthogneisses to estimate the protolith ages at 3902 L 25,3892 ± 33 and 3897 ± 33 Ma for each,supporting the presence of the over 3.9 Ca Iqaluk Gneiss.The geological occurrence that the mafic rocks occur as enclaves within the 3.9 Ga Iqaluk Gneiss indicates that they are the oldest supracrustal rocks in the world.Our geochronological and geological studies show the Uivak Gneiss is quite varied in lithology and age from 3.6 to 〉3.9 Ga,and tentatively classified into six groups based on their ages.The oldest Uivak Gneiss components including the Iqaluk Gneiss are present around the SJHS area,and the orthogneisses become young as it is away.The lines of evidence of overprinting of younger granitoid on older granitoid in small outcrops and geological-map scale as well as presence of inherited zircons even in the oldest suite suggests that crustal reworking played an important role on erasing the ancient crusts. 展开更多
关键词 Eoarchean Geochronology Uivak Gneiss Iqaluk Gneiss Continental recycling The oldest rocks
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Ornithine decarboxylase, mitogen-activated protein kinase and matrix metalloproteinase-2 expressions in human colon tumors 被引量:13
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作者 Takahiro Nemoto Shunichiro Kubota +2 位作者 Hideyuki Ishida Nobuo Murata Daijo Hashimoto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第20期3065-3069,共5页
AIM: To investigate the expressions of omithine decarboxylase (ODC), MMP-2, and Erk, and their relationship in human colon tumors.METHODS: ODC activity, MMP-2 expression, and mitogenactivated protein (MAP) kinase acti... AIM: To investigate the expressions of omithine decarboxylase (ODC), MMP-2, and Erk, and their relationship in human colon tumors.METHODS: ODC activity, MMP-2 expression, and mitogenactivated protein (MAP) kinase activity (Erk phosphorylation) were determined in 58 surgically removed human colon tumors and their adjacent normal tissues, using [1-14C]-ornithine as a substrate, ELISA assay, and Western blotting, respectively.RESULTS: ODC activity, MMP-2 expression, and Erk phosphorylation were significantly elevated in colon tumors, compared to those in adjacent normal tissues. A significant correlation was observed between ODC activities and MMP-2 levels.CONCLUSION: This is the first report showing a significant correlation between ODC activities and MMP-2 levels in human colon tumors. As MMP-2 is involved in cancer invasion and metastasis, and colon cancer overexpresses ODC, suppression of ODC expression may be a rational approach to treat colon cancer which overexpresses ODC. 展开更多
关键词 Ornithine decarboxylase Human colon tumors mitogen activated protein
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Computed tomography-based finite element analysis to assess fracture risk and osteoporosis treatment 被引量:6
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作者 Kazuhiro Imai 《World Journal of Experimental Medicine》 2015年第3期182-187,共6页
Finite element analysis(FEA) is a computer technique of structural stress analysis and developed in engineering mechanics. FEA has developed to investigate structural behavior of human bones over the past 40 years. Wh... Finite element analysis(FEA) is a computer technique of structural stress analysis and developed in engineering mechanics. FEA has developed to investigate structural behavior of human bones over the past 40 years. When the faster computers have acquired, better FEA, using 3-dimensional computed tomography(CT) has been developed. This CT-based finite element analysis(CT/FEA) has provided clinicians with useful data. In this review, the mechanism of CT/FEA, validation studies of CT/FEA to evaluate accuracy and reliability in human bones, and clinical application studies to assess fracture risk and effects of osteoporosis medication are overviewed. 展开更多
关键词 Finite element analysis Bone MECHANICS HIP FRACTURE OSTEOPOROSIS VERTEBRAL FRACTURE FRACTURE risk
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The second continent:Existence of granitic continental materials around the bottom of the mantle transition zone 被引量:5
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作者 Kenji Kawai Shinji Yamamoto +1 位作者 Taku Tsuchiya Shigenori Maruyama 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第1期1-6,共6页
It has been thought that granitic crust, having been formed on the surface, must have survived through the Earth's evolution because of its buoyancy. At subduction zones continental crust is predominantly created by ... It has been thought that granitic crust, having been formed on the surface, must have survived through the Earth's evolution because of its buoyancy. At subduction zones continental crust is predominantly created by arc magmatism and is returned to the mantle via sediment subduction, subduction erosion, and continental subduction. Granitic rocks, the major constituent of the continental crust, are lighter than the mantle at depths shallower than 270 km, but we show here, based on first principles calcu- lations, that beneath 270 km they have negative buoyancy compared to the surrounding material in the upper mantle and transition zone, and thus can be subducted in the depth range of 270-660 km. This suggests that there can be two reservoirs of granitic material in the Earth, one on the surface and the other at the base of the mantle transition zone (MTZ). The accumulated volume of subducted granitic material at the base of the MTZ might amount to about six times the present volume of the continental crust. Our calculations also show that the seismic velocities of granitic material in the depth range from 270 to 660 km are faster than those of the surrounding mantle. This could explain the anomalous seismic-wave velocities observed around 660 km depth. The observed seismic scatterers and reported splitting of the 660 km discontinuity could be due to jadeite dissociation, chemical discontinuities between granitic material and the surrounding mantle, or a combination thereof. 展开更多
关键词 Continental growthGraniteFirst principlesMantle transition zoneTectonicsGeodynamics
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Anti-Melanogenesis Activity of Supercritical Carbon Dioxide Extract from Perilla frutescens Seeds 被引量:1
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作者 Satoshi Suzuki Hitomi Fujisawa +1 位作者 Junpei Abe Ken-ichi Kimura 《Advances in Biological Chemistry》 CAS 2023年第1期42-55,共14页
Perilla frutescens seed (PFS) oil is reported to inhibit skin photoaging;however, its effect on melanogenesis has not yet been investigated. Herein, we tested the anti-melanogenesis activity of an oil-based extract fr... Perilla frutescens seed (PFS) oil is reported to inhibit skin photoaging;however, its effect on melanogenesis has not yet been investigated. Herein, we tested the anti-melanogenesis activity of an oil-based extract from PFS with supercritical carbon dioxide (scCO<sub>2</sub>). In a cell culture system, B16 mouse melanoma cells were treated with the PFS scCO<sub>2</sub> extract and other samples. The PFS scCO<sub>2</sub> extract decreased melanin production by approximately 90% in B16 mouse melanoma cells without cytotoxicity at 100 μg/mL. This effect was greater than that of the well-known melanogenesis inhibitor, kojic acid. Although a hexane-extracted PFS oil and a squeezed PFS oil also decreased melanin production in the B16 cells, the inhibitory effect of the PFS scCO<sub>2</sub> extract was higher than both of these. Chemical analysis of the PFS scCO<sub>2</sub> extract and squeezed PFS oil showed that almost 90% of the components of both oils were α-linolenic acid, linoleic acid, and oleic acid. Furthermore, the ratio of those three fatty acids across both samples was almost the same. When the three fatty acids were mixed in the same ratio as in the PFS scCO<sub>2</sub> extract, the IC<sub>50</sub> of the mixture for melanin production in B16 melanoma cells was identical to that of the PFS scCO<sub>2</sub> extract. However, the IC<sub>50</sub> of the squeezed PFS oil was approximately 6.6 times higher than that of the mixture. Although those fatty acids are the main inhibitory ingredients against melanin production in all of the extracts, some factor(s) in the squeezed PFS reduce their affinity with the cells. These results indicated that the PFS scCO<sub>2</sub> extract could be a superior melanogenesis inhibitor. Although its main ingredients are probably the same as those of the squeezed PFS oil, it is necessary to extract with scCO<sub>2</sub> for stronger anti-melanogenesis activity. 展开更多
关键词 Perilla frutescens MELANOGENESIS Supercritical Carbon Dioxide B16 Mouse Melanoma Cells
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A study on the interaction between ferric ion and silicic acid in hydrosphere: Si-containing ferruginous deposits formed in neutral hot spring waters
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作者 Gaowa Naren Akane Miyazaki +4 位作者 Motoyuki Matsuo BAI Shuqin Kotaro Yonesu Yoshihiro Okaue Takushi Yokoyama 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2013年第1期27-34,共8页
Five ferruginous deposit samples formed from neutral hot springs were analyzed to determine whether they consisted of a mixture of silica, hydrous iron oxide or iron silicate by differential thermal analysis (DTA), in... Five ferruginous deposit samples formed from neutral hot springs were analyzed to determine whether they consisted of a mixture of silica, hydrous iron oxide or iron silicate by differential thermal analysis (DTA), infrared (IR) spectroscopy, powder X-ray diffraction (XRD), and 57Fe Mssbauer spectroscopy. The Si/Fe atomic ratios of the deposits ranged from 0.25 to 0.45, and were smaller than those of hisingerite (12), but apparently close to those of siliceous ferrihydrite (0.250.5). Si was confirmed to be present as monomeric or oligomeric silicate from the Si-O stretching vibration frequencies on the IR spectra. Judging from the results of DTA, which minerals starting to produce after heating, and a relationship between Si-O stretching vibration frequency and Si/Fe atomic ratio proposed by Henmi et al. (1981), all the deposits in this study were concluded to be mixtures of various siliceous ferri-hydrites with low and high Si/Fe atomic ratios. Moreover, by comparing the chemical properties of hot spring waters, the formation conditions of siliceous ferrihydrite were also discussed. 展开更多
关键词 温泉水 硅酸盐 三价铁离子 SI 相互作用 中性 铁质 伸缩振动频率
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Nine requirements for the origin of Earth’s life:Not at the hydrothermal vent, but in a nuclear geyser system
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作者 Shigenori Maruyama Ken Kurokawa +3 位作者 Toshikazu Ebisuzaki Yusuke Sawaki Konomi Suda M. Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第4期1337-1357,共21页
The origin of life on Earth remains enigmatic with diverse models and debates.Here we discuss essential requirements for the first emergence of life on our planet and propose the following nine requirements:(1)an ener... The origin of life on Earth remains enigmatic with diverse models and debates.Here we discuss essential requirements for the first emergence of life on our planet and propose the following nine requirements:(1)an energy source(ionizing radiation and thermal energy);(2)a supply of nutrients(P.K.REE.etc.);(3)a supply of life-constituting major elements;(4)a high concentration of reduced gases such as CH4,HCN and NH3;(5)dry-wet cycles to create membranes and polymerize RNA;(6)a non-toxic aqueous environment;(7)Na-poor water;(8)highly diversified environments,and(9)cyclic conditions,such as dayto-night,hot-to-cold etc.Based on these nine requirements,we evaluate previously proposed locations for the origin of Earth’s life,including:(1)Darwin’s"warm little pond",leading to a"prebiotic soup"for life;(2)panspermia or Neo-panspermia(succession model of panspermia);(3)transportation from/through Mars;(4)a deepsea hydrothermal system;(5)an on-land subduct ion-zone hot spring,and(6)a geyser systems driven by a natural nuclear reactor.We conclude that location(6)is the most ideal candidate for the o rigin point for Earth’s life because of its efficiency in continuously supplying both the energy and the necessary materials for life,thereby maintaining the essential"cradle"for its initial development.We also emphasize that falsifiable working hypothesis provides an important tool to evaluate one of the biggest mysteries of the universe-the origin of life. 展开更多
关键词 ORIGIN of Earth's LIFE NUCLEAR geyser SYSTEM EMERGENCE and evolution of LIFE Falsifiability
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Implication for Designing a REDD+ Program in a Frontier of Oil Palm Plantation Development: Evidence in East Kalimantan, Indonesia
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作者 Daisuke Terauchi Ndan Imang +4 位作者 Martinus Nanang Masayuki Kawai Mustofa Agung Sardjono Fadjar Pambudhi Makoto Inoue 《Open Journal of Forestry》 2014年第3期259-277,共19页
To examine the REDD+ (Reducing Emissions from Deforestation and Forest Degradation) program as an alternative to an oil palm plantation in West Kutai district of East Kalimantan, we determined the profitability of lan... To examine the REDD+ (Reducing Emissions from Deforestation and Forest Degradation) program as an alternative to an oil palm plantation in West Kutai district of East Kalimantan, we determined the profitability of land use and REDD+, and the land use preferences and practices of the local people, as well as their participation in and preferences for forestry programs. Our findings indicate the following: 1) the profitability of an oil palm plantation was higher than that from other land uses and the REDD+ program;2) the local preferences for land uses were mostly consistent with the profitability of the land uses, except for oil palm plantation due to non-financial concerns;3) the local people combined each land use in accordance with their various needs;and 4) the local people were interested in a Forest and Land Rehabilitation (RHL) program in nonforestry zones. Considering these evidences, an improved RHL program based on an intensive agroforestry system and a conservation-based REDD+ program based on existing customary conservation forest management by the local people are proposed. Given the high opportunity cost and the low preference for an oil palm plantation, designing the REDD+ program by paying attention to the non-financial benefits for a community is a way forward. To enhance the non-financial benefits, it is important to take into consideration local preferences and livelihood activities in designing the REDD+ program. This study also implies the need for a reconsideration of the position of participation of local people in the safeguards of REDD+. 展开更多
关键词 REDD+ Oil Palm PLANTATION Local People LAND USE PREFERENCE LAND USE PROFITABILITY
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In Vivo Investigation of Zr-Based Bulk Metallic Glasses Sub-Periosteally Implanted on the Bone Surface
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作者 Kazuhiro Imai 《Journal of Materials Science and Chemical Engineering》 2016年第1期46-51,共6页
Bulk metallic glasses (BMG) show higher strength and lower Young’s modulus than SUS 316L stainless steel and Ti-6Al-4V alloys. This study aimed to investigate the reaction of Zr-based BMG sub-periosteally implanted o... Bulk metallic glasses (BMG) show higher strength and lower Young’s modulus than SUS 316L stainless steel and Ti-6Al-4V alloys. This study aimed to investigate the reaction of Zr-based BMG sub-periosteally implanted on the surface of the rat femur, thereby evaluate the possibility of the BMG as biomaterials for osteosynthetic devices. Zr<sub>65</sub>Al<sub>7.5</sub>Ni<sub>10</sub>Cu<sub>17.5 </sub>BMG ribbons with 10 mm length, 2 mm width and 0.5 mm thickness were implanted sub-periosteally on the femur surface in three male Wistar rats for 6 weeks. Systemic effects were evaluated by measuring Cu and Ni levels in the blood, and local effects were evaluated by the histological observation of the surrounding soft tissues in contact with the BMG. The reaction of the surface of the BMG was examined with scanning electron microscopy. No increase of Cu and Ni levels in the blood was recognized. In the scanning electron microscopy observation, spherical deposits which were considered as sodium chloride crystals were observed. Neither breakage nor pitting corrosion was noted. BMG will be a promising metallic biomaterial for osteosynthetic device that must be removed. 展开更多
关键词 Amorphous Alloy Bulk Metallic Glasses Biomaterial Osteosynthetic Device
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Modification of the High-Pressure-Type Chromites into the Low-Pressure-Type: Petrological Investigation of the Podiform Chromitites in the Luobusa Ophiolite, Tibet
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作者 YAMAMOTO Shinji KOMIYA Tsuyoshi MARUYAMA Shigenori 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第A02期104-104,共1页
The podiform chromitites in the Luobusa ophiolite, Southem Tibet, have received much attention because of the presence of ultrahigh-pressure minerals, such as micro- diamonds (Bai et al., 1993; Yang et al., 2007; Xu ... The podiform chromitites in the Luobusa ophiolite, Southem Tibet, have received much attention because of the presence of ultrahigh-pressure minerals, such as micro- diamonds (Bai et al., 1993; Yang et al., 2007; Xu et al., 展开更多
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A Peptide Nucleic Acid to Reduce Type I Collagen Production by Fibroblast Cells
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作者 Yasutada Imamura Suzuka Tsuboi +2 位作者 Toru Sugiyama Atsushi Kittaka Yonchol Shin 《Open Journal of Medicinal Chemistry》 2015年第1期1-8,共8页
In this study, we prepared a peptide nucleic acid (PNA) against the gene coding for the human alpha 1 chain of type I collagen. This PNA was incorporated into normal human fibroblast cells by electroporation, leading ... In this study, we prepared a peptide nucleic acid (PNA) against the gene coding for the human alpha 1 chain of type I collagen. This PNA was incorporated into normal human fibroblast cells by electroporation, leading to a decrease in the mRNA level of the gene. Furthermore, mRNA for the alpha 2 chain of type I collagen was also reduced. The production of collagen protein exhibited a similar profile to the changes in mRNA. These results indicate that PNA targeting COL1A1 is effective as an antigene reagent, and opens the possibility of future clinical applications in fibroproliferative disorders. 展开更多
关键词 COLLAGEN PNA ANTIGENE FIBROSIS VIMENTIN
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Richard N.Cooper:For an Interdependent World
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作者 LIU CHEN 《China Today》 2021年第5期52-53,共2页
AT their virtual meeting on February 19,leaders of the Group of Seven(G7)pledged in a joint statement to make 2021 a turning point for multilateralism.Amid global volatility,multilateral cooperation is facing a range ... AT their virtual meeting on February 19,leaders of the Group of Seven(G7)pledged in a joint statement to make 2021 a turning point for multilateralism.Amid global volatility,multilateral cooperation is facing a range of new challenges that need the guidance of innovation and inspiration of a practical trailblazing approach.Nonetheless,despite such uncertainty across the world,the pledge from the G7 sent a positive sign.The stance of supporting and encouraging international cooperation taken by the G7 since its founding in 1975 is reminiscent of the study of the world renowned economist Richard N.Cooper,widely recognized as the founder of study on international cooperation in economics.Cooper helped lay the theoretical ground for the founding of G7. 展开更多
关键词 FOUNDING STATEMENT TRAIL
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GENOMES UNCOUPLED PROTEIN1 binds to plastid RNAs and promotes their maturation
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作者 Qian Tang Duorong Xu +8 位作者 Benjamin Lenzen Andreas Brachmann Madhura MYapa Paymon Doroodian Christian Schmitz-Linneweber Tatsuru Masuda Zhihua Hua Dario Leister Tatjana Kleine 《Plant Communications》 CSCD 2024年第12期73-90,共18页
Plastid biogenesis and the coordination of plastid and nuclear genome expression through anterograde and retrograde signaling are essential for plant development.GENOMES UNCOUPLED1(GUN1)plays a central role in retrogr... Plastid biogenesis and the coordination of plastid and nuclear genome expression through anterograde and retrograde signaling are essential for plant development.GENOMES UNCOUPLED1(GUN1)plays a central role in retrograde signaling during early plant development.The putative function of GUN1 has been extensively studied,but its molecular function remains controversial.Here,we evaluate published transcriptome data and generate our own data from gun1 mutants grown under signaling-relevant condi-tions to show that editing and splicing are not relevant for GUN1-dependent retrograde signaling.Our study of the plastid(post)transcriptome of gun1 seedlings with white and pale cotyledons demonstrates that GUN1 deficiency significantly alters the entire plastid transcriptome.By combining this result with a penta-tricopeptide repeat code-based prediction and experimental validation by RNA immunoprecipitation ex-periments,we identified several putative targets of GUN1,including tRNAs and RNAs derived from ycf1.2,rpoC1,and rpoC2 and the ndhH–ndhA–ndhI–ndhG–ndhE–psaC–ndhD gene cluster.The absence of plastid rRNAs and the significant reduction of almost all plastid transcripts in white gun1 mutants ac-count for the cotyledon phenotype.Our study provides evidence for RNA binding and maturation as the long-sought molecular function of GUN1 and resolves long-standing controversies.We anticipate that ourfindings will serve as a basis for subsequent studies on mechanisms of plastid gene expression and will help to elucidate the function of GUN1 in retrograde signaling. 展开更多
关键词 GUN1 MORF2 plastid(post)transcriptome retrograde signaling RIP-seq RNA binding protein
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