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Ontogeny of Psychomotor and Sensory Functions in the Rat: Effects of Sexual Dimorphism
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作者 Abdoulaye Bâ Lociné Bamba Seydou Silué 《Journal of Behavioral and Brain Science》 2023年第11期206-225,共20页
Background: We studied the development of eight (8) different psychomotor and sensory functions in male and female rats, from postnatal day 10 to 45, with the aim of determining whether the ontogenesis of these functi... Background: We studied the development of eight (8) different psychomotor and sensory functions in male and female rats, from postnatal day 10 to 45, with the aim of determining whether the ontogenesis of these functions was subject to sexual dimorphism. Methods: Wistar rats bred according to standard conditions in our laboratories were put into reproduction. Ten days after whelping, male and female pups were identified and subjected to a battery of behavioral tests on postnatal days 10, 15, 20, 25, 30 and 45, to assess the development of the following psychomotor and sensory functions: Exploratory activity, locomotor activity, emotional defecation, hind paws lifting reflex latency, wire-grasping time, Latencies of execution of crawling along the wire and of leap onto the ground, nociception (tail flick) and body weight. Results: Only complex brain functions generated by cerebral cortex activities, i.e. exploratory activity and leap execution latency, do not undergo differential development sex-dependent. However, voluntary motor functions initiated in the motor cortex, and requiring high peripheral muscle performance such as crawling execution latency and wire-grasping time developed more rapidly in males than in females. Correlatively, body weight i.e. muscle mass index increased more speedily in males than in females. On the other hand, studies of automatic motor functions such as locomotor activity, and reflex motor functions i.e. hind paws lifting reflex latency and tail flick latency showed earlier development in females than in males. In addition, the study of emotional response, an emanation of limbic structures, showed prodigious development in females compared to males. Conclusion: Our studies have shown that there is a developmental sexual dimorphism of the central nervous system in the rat. Indeed, studies of automatic and reflex motor functions, whose activities are essentially linked to the spinal cord and brainstem, indicated that hindbrain areas develop more speedily in females than in males. Likewise, study of the emotional response emanating from diencephalic limbic structures, in particular the hypothalamus, showed a prodigious and early development in females compared to males. Taken together, our studies indicate that the vast majority of brain structures and functions reached maturation earlier in females than in males. Estrogen is the trigger hormone for early maturation of the female brain. 展开更多
关键词 Developing Rats Brain ontogeny Psychomotor Functions Sexual Dimorphism
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Ontogeny,growth and development of the small intestine:Understanding pediatric gastroenterology 被引量:5
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作者 Laurie A Drozdowski Tom Clandinin Alan BR Thomson 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第7期787-799,共13页
Throughout our lifetime,the intestine changes.Some alterations in its form and function may be genetically determined,and some are the result of adaptation to diet,temperature,or stress.The critical period programming... Throughout our lifetime,the intestine changes.Some alterations in its form and function may be genetically determined,and some are the result of adaptation to diet,temperature,or stress.The critical period programming of the intestine can be modified,such as from subtle differences in the types and ratios of n3:m6 fatty acids in the diet of the pregnant mother,or in the diet of the weanlings.This early forced adaptation may persist in later life,such as the unwanted increased intestinal absorption of sugars,fatty acids and cholesterol.Thus,the ontogeny,early growth and development of the intestine is important for the adult gastroenterologist to appreciate,because of the potential for these early life events to affect the responsiveness of the intestine to physiological or pathological challenges in later life. 展开更多
关键词 Intestinal development ontogeny PEDIATRICS
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Anatomy and ontogeny of unisexual flowers in dioecious Woonyoungia septentrionalis (Dandy) Law (Magnoliaceae) 被引量:3
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作者 Lin FU Qing-Wen ZENG +1 位作者 Jing-Ping LIAO Feng-Xia XU 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第4期263-272,共10页
Woonyoungia septentrionalis (Dandy) Law is aceae. The floral morphology and structure of the species a dioecious species with unisexual flowers in Magnoliare conspicuously different from other species and are import... Woonyoungia septentrionalis (Dandy) Law is aceae. The floral morphology and structure of the species a dioecious species with unisexual flowers in Magnoliare conspicuously different from other species and are important to the study of floral phylogeny in this family. The floral anatomy and ontogeny were investigated to evaluate the systematic position of W. septentrionalis, using scanning electron microscopy and light microscopy. All of the floral organs are initiated acropetally and spirally. The carpels are of conduplicated type without the differentiation of stigma and style. The degenerated stamens in the female flowers have the same structures as the normal stamens at the earlier developmental stages, but they do not undergo successive development and eventually degenerate. The male floral apex was observed to have the remnants of carpels in a few investigated samples. As the bisexual flower features could be traced both in the male and female flowers in W. septentrionalis, it suggests that the flower sex in Magnoliaceae tends toward unisexual. As well as the unisexual flowers, the reduced tepals and carpels and concrescence of carpels conform to the specialized tendency in Magnoliaceae, which confirms the derived position of W. septentrionalis in this family. As the initiation pattern of floral parts of W. septentrionalis is very similar to other species in this family, it needs further investigation and especially comparison with species in Kmeria to evaluate the separation of Woonyoungia. 展开更多
关键词 floral anatomy MAGNOLIACEAE ontogeny Woonyoungia septentrionalis (Dandy) Law.
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Ontogeny of the Traumatocrinus hsui 被引量:2
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作者 WANG Chuanshang CHEN Xiaohong WANG Xiaofeng CHENG Long 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第3期544-548,共5页
It is suggested that the characters of Traumatocrinus hsui Mu infants change remarkably in different ages;however,the characters of adult individuals are comparatively stable.The present study examined specimens of in... It is suggested that the characters of Traumatocrinus hsui Mu infants change remarkably in different ages;however,the characters of adult individuals are comparatively stable.The present study examined specimens of infant and adult individuals of T.hsui.Based on these observations,the authors divided the ontogeny of T.hsui into four infant stages(infant stageⅠ-Ⅳ)and one adult stage.In addition,the characters of the anal pyramid are supplemented and the infrabasal plates of T.hsui are confirmed in the present paper for the first time. 展开更多
关键词 Traumatocrinus hsui ontogeny infant individual
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Ontogeny of expression of transforming growth factor-βand its receptors and their possible relationship with scarless or scar-forming healing in human fetal and postnatal skins 被引量:1
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作者 Chen Wei Fu Xiaobing Ge Shili~1 Sun Tongzhu Zhou Gang Jiang Duyin Sheng Zhiyong Research Department of Burn Institute,304th Hospital,Beijing 100037 Institute of Radiation Medicine,Academy of Military Medicine Sciences,Beijing 100850,People’s Republic of China 《感染.炎症.修复》 2003年第4期197-205,共9页
Fetal eutaneous wounds that oeeur in earlygestation heal without sear formation.Althoughmueh work has been done to eharaeterize the roleof transforming growth
关键词 in et for of ontogeny of expression of transforming growth factor and its receptors and their possible relationship with scarless or scar-forming healing in human fetal and postnatal skins TGF were that TBR EGA with
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Ontogeny of immune organs during early development stage of P. crocea
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作者 XU Xiaojin WENG Zhaohong +1 位作者 WANG Jun SU Yongquan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第6期72-82,共11页
A histological and ultrastructural study was performed on the development of the head kidney, thymus, and spleen in Pseudosciaena crocea aging in range from just hatching to the 60th day after hatching (DAH). Head k... A histological and ultrastructural study was performed on the development of the head kidney, thymus, and spleen in Pseudosciaena crocea aging in range from just hatching to the 60th day after hatching (DAH). Head kidney was first present on the 3rd DAH. Primordial haemopoietic stem cells were first observed in the head kidney which rapidly differentiate into different cellular types. Progenitor spleen was present on the 4th DAH, located close to the gut, which soon became rich in blood capillaries, red blood cells and thrombocytes. The thymus was obvious on the 4th DAH, and was located on either side of the upper comer of the opercular cavity, closely under the membrance of the opercuhr cavity. The thymus was the last lymphoid organ to appear but showed a quick development. This organ seemed to originate from haemopoietic stem cells migrating from the head region of the kidney. The thymus consisted of outer thymocytic and inner epithelioid zones. There was no obvious demarcation between them, but both zones were visible. Small lymphocytes appeared, or lymphoid organs become lymphoid, in the sequence thymus, head kidney and spleen. Only a small number of lymphocytes appeared in the later stages. Non-specific systems may play an important role in the immunocompetence mechanisms of P. crocea during its early development stage. 展开更多
关键词 Pseudosciaena crocea immune organs DEVELOPMENT ontogeny
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What Can Al Learn from Psychology and When Can Al Neglectit?An Ontogeny-Free Study on the Cognition of Numerosity
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作者 Yingjin Xu 《Fudan Journal of the Humanities and Social Sciences》 2023年第4期495-513,共19页
AI has a long tradition of borrowing insights from psychology.There is also a voice of embracing ontogenetic elements in Al since ontogenetically earlier developing subsystems look easier to be the target of computati... AI has a long tradition of borrowing insights from psychology.There is also a voice of embracing ontogenetic elements in Al since ontogenetically earlier developing subsystems look easier to be the target of computational modeling.But due to be the fundamental difference between natural organisms and digital computers on the hardware level,this analogy does not always hold.For instance,as reported(Carey The origin of concepts,Oxford University Press,Oxford,2009a),(Carey in JP 106:220-254,2009b)ontogeny about the development of the cognitive mechanism cannot be smoothly mapped onto an AI context,although many of her psychologi-cal/philosophical insights,especially the indispensability of a quasi-phenomenologi-cal interface for manipulating numerical concepts,could still be kept. 展开更多
关键词 ontogeny Artificial Intelligence(AI) Developmental psychology The cognition of numerosity Give-N-tasks Non-Axiomatic Reasoning System(NARS)
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Role of farnesoid X receptor in establishment of ontogeny of phase-I drug metabolizing enzyme genes in mouse liver 被引量:5
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作者 Lai Peng Stephanie Piekos +1 位作者 Grace L.Guo Xiao-bo Zhong 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2016年第5期453-459,共7页
The expression of phase-I drug metabolizing enzymes in liver changes dramatically during postnatal liver maturation.Farnesoid X receptor(FXR) is critical for bile acid and lipid homeostasis in liver.However,the role o... The expression of phase-I drug metabolizing enzymes in liver changes dramatically during postnatal liver maturation.Farnesoid X receptor(FXR) is critical for bile acid and lipid homeostasis in liver.However,the role of FXR in regulating ontogeny of phase-I drug metabolizing genes is not clear.Hence,we applied RNA-sequencing to quantify the developmental expression of phase-I genes in both Fxr-null and control(C57BL/6) mouse livers during development.Liver samples of male C57BL/6 and Fxr-null mice at6 different ages from prenatal to adult were used.The Fxr-null showed an overall effect to diminish the "day-1 surge" of phase-I gene expression,including cytochrome P450 s at neonatal ages.Among the 185 phase-I genes from 12 different families,136 were expressed,and differential expression during development occurred in genes from all 12 phase-I families,including hydrolysis: carboxylesterase(Ces),paraoxonase(Pon),and epoxide hydrolase(Ephx); reduction: aldoketo reductase(Akr),quinone oxidoreductase(Nqo),and dihydropyrimidine dehydrogenase(Dpyd); and oxidation: alcohol dehydrogenase(Adh),aldehyde dehydrogenase(Aldh),flavin monooxygenases(Fmo),molybdenum hydroxylase(Aox and Xdh),cytochrome P450(P450),and cytochrome P450 oxidoreductase(Por).The data also suggested new phase-I genes potentially targeted by FXR.These results revealed an important role of FXR in regulation of ontogeny of phase-I genes. 展开更多
关键词 Drug metabolizing ENZYMES Farnesoid X receptor Liver ontogeny Fxr-null mouse Gene expression
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Floral Ontogeny of Two Species in Magnolia L. 被引量:2
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作者 Feng-Xia Xu 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2006年第10期1197-1203,共7页
Floral ontogeny is described in two species of genus Magnolia (Magnollaceae), Magnolia alboserlcea Chun et C. Tsoong, and M. amoena Cheng, representing subgenus Magnolia and subgenus Yulani In Magnolia, by using sca... Floral ontogeny is described in two species of genus Magnolia (Magnollaceae), Magnolia alboserlcea Chun et C. Tsoong, and M. amoena Cheng, representing subgenus Magnolia and subgenus Yulani In Magnolia, by using scanning electron microscope (SEM). The sequence of Initiation of floral organs Is from proximal to distal. The three distinct outermost and middle organs are Initiated in sequence, but ultimately form a single whorl, thus their ontogeny Is consistent with a sepal Interpretation. The last three tepals (petals) alternate with the preceding tepal whorl. The members of androeclum and gynoeclum arise spirally, although the androecium shows some Intermedlacy between a spiral and whorled arrangement. The carpel prlmordia initiate in group of four to five. The order of stamen Initiation within each tier Is not determined. The floral ontogeny Is remarkably homogeneous between the subgenus Magnolia and subgenus Yulani that does not support the resuming of genus Yulani. 展开更多
关键词 floral ontogeny Magnolia albosericea Magnolia amoena subgenus Magnolia subgenus Yulania
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Underwater Superoleophobic Crucian Fish Scale:Influence of Ontogeny on Surface Morphologies and Wettability 被引量:1
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作者 Xuelian Gou Zhiguang Guo 《Journal of Bionic Engineering》 SCIE EI CSCD 2019年第6期1061-1067,共7页
Recent development concerning underwater superoleophobic surface has been motivated by fish scales,which are rendered capable of preventing their surfaces from contamination in oil-polluted water.In this paper,for the... Recent development concerning underwater superoleophobic surface has been motivated by fish scales,which are rendered capable of preventing their surfaces from contamination in oil-polluted water.In this paper,for the first time,the variations in surface topography and chemical composition of crucian fish scales at different growth stages have been investigated.The water and oil contact angles,surface morphology and chemical composition of the fish scales were measured by means of contact angle measurements,scanning electron microscopy and Fourier transform infrared spectroscopy,respectively.It is found that surface morphology and chemical composition both have influences on surface wettability of fish scales;fish scale at infant period seems to possess better hydrophilicity than that of fish scales at mature and senescent period.What is more,it is believed that the wettability heavily depends on the surface structures during their growth procedure,which enlightens us to design and fabricate biomimetic multifunctional underwater superoleophobic surfaces inspired by nature. 展开更多
关键词 underwater superoleophobic fish scales ontogeny BIOMIMETIC
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Daily expression of sodium-dependent glucose cotransporter-1protein in jejunum during rat ontogeny
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作者 Juan I.Baston Fabricio D.Cid +1 位作者 Enrique Caviedes-Vidal Juan G.Chediack 《Animal Nutrition》 SCIE 2019年第3期290-296,共7页
It is widely known that intestinal capacities such as the enzymatic hydrolysis of carbohydrates,lipids and proteins,and the subsequent absorption of the hydrolyzed products.are evolutionary matched to dietary loads an... It is widely known that intestinal capacities such as the enzymatic hydrolysis of carbohydrates,lipids and proteins,and the subsequent absorption of the hydrolyzed products.are evolutionary matched to dietary loads and feeding behaviors.In this study,we demonstrate that the protein expression of apically located sodium-dependent glucose cotransporter-1(SGLT-1)throughout rat ontogeny is daily adjusted to afford glucose uptake when the load of this metabolically essential monosaccharide in the intestinal lumen is maximum.The jejunal expression of SGLT-1 protein in 14 one-day-old suckling pups was found to increase at dark and early light phase(P<0.05).when they have a better access to mother milk.In weaning21-d-old and juvenile 28-d-old rats,the cotransporter expression was high throughout the entire day(P<0.05).Finally,adult 90-d-old rats showed a well-developed circadian rhythm for SGLT-1 protein(P<0.05).whose expression increased at late light and dark phase when the highest intestinal glucose load was achieved.To our knowledge,these results are the first reporting the daily profile of SGLT-1 expression during rat early developmental stage and may contribute to understand the biological significance of a well-established molecular capacity to deal with the crucial increase of glucose load in the diet during the weaning process. 展开更多
关键词 Intestinal SGLT-1 Protein EXPRESSION DAILY rhythms ontogeny RAT
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Ontogeny of Drosophila melanogaster female sex-appeal and cuticular hydrocarbons
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作者 Marisa ARIENTI Claude ANTONY +2 位作者 Claude WICKER-THOMAS Jean-Paul DELBECQUE Jean-Marc JALLON 《Integrative Zoology》 SCIE CSCD 2010年第3期272-282,共11页
The chemical communication system in Drosophila melanogaster Meigen,1830 plays a major role in courtship and consists of the male-specific cis-Vaccenyl acetate and sex-specific contact pheromones,cuticular hydrocarbon... The chemical communication system in Drosophila melanogaster Meigen,1830 plays a major role in courtship and consists of the male-specific cis-Vaccenyl acetate and sex-specific contact pheromones,cuticular hydrocarbons(CHC),which build up during ontogeny(first 4 days).They replace longer CHCs,common to both sexes and present only after the imaginal eclosion.A detailed quantitative description of the evolution of cuticular unsaturated hydrocarbons with age is presented here for males and females of different D.melanogaster strains,which have been bred in well controlled environments.Monoenes appear in both sexes at around 12 h,before female dienes.The present paper argues that this is likely linked to the switching on of a new set of genes.Ecdysone,which is more abundant in females than in males during this critical period,might control this switch.Parallel behavioral studies show that whereas female of all ages trigger early mature male courtship steps like wing vibration,only females older than 1 day trigger late courtship steps like attempted copulation.This supports the hypothesis that late male courtship steps might be triggered by the CHCs,which build up after this age,especially female-specific(Z,Z)-7,11-and(Z,Z)-5,9-dienes. 展开更多
关键词 contact pheromones Drosophila melanogaster ecdysone control ontogeny sex differences
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Vestrogothia spinata(Phosphatocopina,Crustacea),Fossils of Orsten-type Preservation from the Upper Cambrian of Western Hunan,South China 被引量:6
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作者 LIU Zheng DONG Xiping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期471-478,共8页
Fossils of Orsten-type preservation represented by the crustacean Skaracarida and Phosphatocopida were found in western Hunan, South China in 2005, including the important phosphatocopid species Vestrogothia spinata b... Fossils of Orsten-type preservation represented by the crustacean Skaracarida and Phosphatocopida were found in western Hunan, South China in 2005, including the important phosphatocopid species Vestrogothia spinata based on exquisitely preserved soft-bodied specimens that allow the first growth stage to be reestablished. The taxonomy of Vestrogothia spinata is revised employing the character of a two-divided limb stem of the mandible. A new foundation for the phylogeny of the Phosphatocopina using mandible characters related to crustacean appendages is postulated. Vestrogothia spinata has only previously been found from Sweden. 展开更多
关键词 Vestrogothia spinata Phosphatocopina CRUSTACEA Orsten-type fossil taxonomy ontogeny Upper Cambrian Hunan South China
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An Adult Specimen of Hongshanosaurus houi (Dinosauria:Psittacosauridae) from the Lower Cretaceous of Western Liaoning Province, China 被引量:6
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作者 YOUHailu XUXing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第2期168-173,共6页
A new specimen consisting of a complete skull and lower jaw was discovered from the Lujiatun bed of the Lower Cretaceous Yixian Formation in the Lujiatun site, Beipiao, western Liaoning Province. It represents an adul... A new specimen consisting of a complete skull and lower jaw was discovered from the Lujiatun bed of the Lower Cretaceous Yixian Formation in the Lujiatun site, Beipiao, western Liaoning Province. It represents an adult specimen of Hongshanosaurus houi. Comparative studies show that Hongshanosaurus is distinguishable from its sister taxon Psittacosaurus by having the preorbital portion about half of the basal skull length, and the elliptical external naris, orbit, and a lower temporal fenestra oriented caudodorsally. 展开更多
关键词 DINOSAURIA Psittacosauridae Hongshanosaurus ontogeny Lower Cretaceous western Liaoning
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A New Juvenile Specimen of Lufengosaurus Huenei Young, 1941 (Dinosauria: Prosauropoda) from the Lower Jurassic Lower Lufeng Formation of Yunnan, Southwest China 被引量:3
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作者 SEKIYA Toru DONG Zhiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第1期11-21,共11页
A skull and a series of associated cervical vertebrae (ZLJ0112) discovered from the Lower Lufeng Formation (Lower Jurassic) are determined as a juvenile specimen of Lufengosaurus huenei Young 1941 based on amended... A skull and a series of associated cervical vertebrae (ZLJ0112) discovered from the Lower Lufeng Formation (Lower Jurassic) are determined as a juvenile specimen of Lufengosaurus huenei Young 1941 based on amended autapomorphies. Differences between ZLJ0112 and the holotype (subadult specimen) are considered as ontogenetic characteristic changes of L. huenei. Since some of these differences are present in other prosauropod dinosaurs (i.e., forms of the maxillary vascular foramen are irregular; the frontal contribution to the dorsal margin of the orbit is substantial; the frontal contribution to the supratemporal fossa is absent; the supratemporal fenestra is visible in lateral view; the supraoccipital inclined at 75 degrees; the parasphenoid rostrum lies level with the occipital condyle; the retroarticular process is short; the axial postzygapophysis project caudally beyond the end of the centrum) they may be common ontogenetic changes in prosauropod dinosaurs. 展开更多
关键词 Prosauropod Lufengosaurus huenei JUVENILE ontogeny PHYLOGENY Lufeng County Yunnan Province
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New Material of Pterosaur Sinopterus (Reptilia:Pterosauria) from the Early Cretaceous Jiufotang Formation,Western Liaoning,China 被引量:1
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作者 Lü Junchang LIU Jinyuan +3 位作者 WANG Xuri GAO Chunling MENG Qingjin JI Qiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期783-789,共7页
Based on a new nearly complete postcranial skeleton of an adult specimen of Sinopterus from the Early Cretaceous Jiufotang Formation of western Liaoning, China, the diagnosis of Sinopterus is amended. The revised diag... Based on a new nearly complete postcranial skeleton of an adult specimen of Sinopterus from the Early Cretaceous Jiufotang Formation of western Liaoning, China, the diagnosis of Sinopterus is amended. The revised diagnosis of Sinopterus includes skull relatively elongate with weakly developed cranial crest; ratio of the length of Ph2d4 to that of Ph1d4 is approximately 0.73; ratio of the length of wing metacarpal to that of metatarsal 3 is 4.5; ratio of the length of mt3 to that of tibia is approximately 0.21, and wing phalanges 1 and 2 are straight. Comparison between the ratios of the limb bones between non-adult and adult individuals of Sinopterus indicates that during the ontogenetic process, some ratios between bones are constant, such as the first wing phalanx to the second wing phalanx, the wing metacarpal to the metatarsal 3, metatarsal 3 to the tibia, but others are not, such as humerus to wing metacarpal and femur to tibia, in which the former grows faster than the latter. 展开更多
关键词 Sinopterus amended diagnosis ontogeny Jiufotang Formation Early Cretaceous western Liaoning China
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Dimorphism of Bivalved Arthropod Branchiocaris? Yunnanensis from the Early Cambrian Chengjiang Biota, South China 被引量:1
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作者 WU Yu FU Dongjing +2 位作者 ZHANG Xingliang Allison C. DALEY SHU Degan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第3期818-826,共9页
The bivalved arthropod Branchiocaris? yunnanensis Hou, 1987 is redescribed on the basis of new fossil material from the early Cambrian Chengjiang biota, South China. In total, 81 specimens have been examined. The car... The bivalved arthropod Branchiocaris? yunnanensis Hou, 1987 is redescribed on the basis of new fossil material from the early Cambrian Chengjiang biota, South China. In total, 81 specimens have been examined. The carapace comprises two identical valves, each valve are sub-circular in outline, ranging from 24 mm to 58 mm in length, and from 15 mm to 46 mm in height. The dorsal margin is straight and bears two short cardinal spines. The valve surface is either smooth or ornamented with polygonal reticular structures, which may result from different preservation conditions. Two morphotypes have been recognized based on the presence or absence of a subdorsal swelling of the valve, which is convex dorsolaterally and extends beyond the dorsal margin when it appears. Statistic and ontogenetic analyses show both morphotypes grow isometrically and have the same growth trajectory. Therefore, the two morphotypes are interpreted as dimorphism within the same species. Our results are helpful for investigating the taxonomy and ontogeny of arthropod fossils and suggest that dimorphism might be fairly common in these early arthropods. 展开更多
关键词 ARTHROPODA Branchiocaris DIMORPHISM ontogeny Chengjiang biota
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Evolution of Dentary Diastema in Iguanodontian Dinosaurs 被引量:1
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作者 Katsuhiro KUBOTA Yoshitsugu KOBAYASHI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第1期39-45,共7页
The dentary diastema of iguanodontians has been considered to be related to its unique jaw mechanism for herbivorous adaptation. The dentary and diastema lengths of iguanodontians were measured and compared to elucida... The dentary diastema of iguanodontians has been considered to be related to its unique jaw mechanism for herbivorous adaptation. The dentary and diastema lengths of iguanodontians were measured and compared to elucidate the evolution of iguanodontian diastema. A gap in ratios between most non-hadrosaurid iguanodontians and hadrosaurids was observed, suggesting that all non- hadrosaurid iguanodontians, expect for Ouranosaurus nigeriensis and Protohadros byrdi, lack a diastema or have a short diastema, although some other taxa have been considered to have a long diastema in previous studies. In non-hadrosaurid iguanodontians, some large-sized forms, such as Iguanodon bernissartensis, Shuangmiaosaurus gilmorei, and possibly Eolambia caroljonesa, had a short diastema through ontogeny, whereas Ouranosaurus nigeriensis and Protohadros byrdi developed a long diastema convergently. The development of a long diastema of hadrosaurine hadrosaurids may be different from that of lambeosaurine hadrosaurids. Some hadrosaurines (Edmontosaurus annectens, Edmontosaurus regalis, and Saurolophus angustirostris) may have developed a long diastema in the subadult stage and showed little elongation of dentary diastema through ontogeny. Lambeosaurines (Corythosaurus casuarius and Lambeosaurus lambei) tend to have a short diastema in the embryonic and subadult stages, and an elongated diastema from the subadult to adult stages. 展开更多
关键词 CRETACEOUS dentary diastema DINOSAUR iguanodontian ontogeny
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New Material of Zhenyuanopterus(Pterosauria) from the Early Cretaceous Yixian Formation of Western Liaoning 被引量:1
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作者 TENG Fangfang L Junchang +2 位作者 WEI Xuefang HSIAO Yufu Michael PITTMAN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第1期1-5,共5页
A new partial specimen of Zhenyuanopterus from the Lower Cretaceous Yixian Formation of Beipiao city, Liaoning Province is described. This specimen is slightly larger than half the size of the holotype. Although it is... A new partial specimen of Zhenyuanopterus from the Lower Cretaceous Yixian Formation of Beipiao city, Liaoning Province is described. This specimen is slightly larger than half the size of the holotype. Although it is not complete, it provides new information on Zhenyuanopterus both in taxonomy and ontogeny: the total number of the caudal vertebrae is 15; the forelimb is more robust than the hindlimb; the growth rate of the humerus and femur is constant, and their ratio is about 1. Compared with the holotype, the scapula and coracoid grow faster than the humerus and the femur. The scapula and coracoid may slow their growth rate after a certain ontogenetic stage. The pectoral girdle, robust forelimb and weak hindlimb of the new material(XHPM1088) together with data from the holotype of Zhenyuanopterus indicate that this taxon spent less time on land than in the sky or other ecological niches such as forests and cliffs. 展开更多
关键词 Boreopteridae Zhenyuanopterus ontogeny
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Elevated Concentrations of Dietarily-Important Trace Elements and Macronutrients in Edible Leaves and Grain of 27 Cowpea (<i>Vigna unguiculata</i>L. Walp.) Genotypes: Implications for Human Nutrition and Health 被引量:1
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作者 Alphonsus K. Belane Felix D. Dakora 《Food and Nutrition Sciences》 2012年第3期377-386,共10页
Legumes are a good source of calories, protein and mineral nutrients for human nutrition and health. In this study, the edible leaves and grain of 27 field-grown cowpea genotypes were assessed for trace elements and m... Legumes are a good source of calories, protein and mineral nutrients for human nutrition and health. In this study, the edible leaves and grain of 27 field-grown cowpea genotypes were assessed for trace elements and macronutrient den-sity at Manga in the Sudano-Sahelian zone of Ghana in 2005 and 2006, using inductively coupled plasma-mass spectrometry. The genotypes differed markedly in their accumulation of trace elements and major nutrients in edible leaves and grain. Except for P, the concentrations of K, Ca, Mg, S and Na were much higher in edible cowpea leaves than grain in 2005. A similar pattern was observed for Ca, Mg, S, Na in 2006. However, more dramatic variations were found in the micronutrient concentrations between edible cowpea leaves and grain. The levels of the trace elements Fe, Cu, Zn, Mn and B were sometimes 2- to 20-fold greater in leaves than grain of cowpea. Furthermore, there were strong genotypic differences in mineral density of cowpea leaves and grain. For the major nutrients, for example, IT93K-2045-29 and IT90K-59 accumulated greater concentrations of P, K, Ca, S and Na in both edible leaves and grain in 2006, while ITH98-46, which showed the least macronutrient density, exhibited the highest concentrations of Fe, Zn, Cu, Mn and B in edible leaves, as well as Fe, Cu and Mn in grain. These results have implications for cowpea breeding, as well as for human nutrition and health. 展开更多
关键词 CALORIES Protein Trace Elements MACRONUTRIENTS Nutrition ontogeny
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