Termite coprolites (Blattodea: Isoptera) from the Early Cretaceous of eastern Inner Mongolia, Northeast China

2022 ◽  
Vol 5 (1) ◽  
Author(s):  
CHONG DONG ◽  
GONG-LE SHI ◽  
ZI-XI WANG ◽  
DI-YING HUANG
Keyword(s):  
Early Cretaceous ◽  
Cross Sections ◽  
Inner Mongolia ◽  
Northeast China ◽  
Feeding Habits ◽  
Feeding Preference ◽  
Elliptical Cross ◽  
Faecal Pellets ◽  
Wood Debris ◽  
Eastern Inner Mongolia

Well-preserved coprolites (fossil faecal pellets) were found from lignite seams of the Lower Cretaceous Huolinhe Formation at the Huolinhe Basin in eastern Inner Mongolia, Northeast China. These coprolites provide a combination of following features: oval to cylindrical shaped with six longitudinal ridges, hexagonal to elliptical cross-sections, and one blunt end and the other pointed end. According to these distinct features and their size range, the producers of these coprolites are attributed to termites. Termites were estimated to have originated in the earliest Cretaceous with an evolutionary radiation in the Early Cretaceous. The presence of wood debris in the coprolites indicate that the Early Cretaceous termites from the Huolinhe Basin had wood-feeding habits; and anatomical features displaying on the wood debris further suggest their feeding preference was coniferous wood. Besides, the results of a k-means clustering analysis performed for these coprolites indicate that three clusters with different proportion were present, suggesting the division of labor in termites’ sociality existed as early as the Early Cretaceous.

Leaves of Taxus with cuticle micromorphology from the Early Cretaceous of eastern Inner Mongolia, Northeast China

2021 ◽  
pp. 104588
Author(s):  
Chong Dong ◽  
Gongle Shi ◽  
Fabiany Herrera ◽  
Yongdong Wang ◽  
Zixi Wang ◽  
...  
Keyword(s):  
Early Cretaceous ◽  
Inner Mongolia ◽  
Northeast China ◽  
Eastern Inner Mongolia

scholarly journals Male spike strobiles withGnetumaffinity from the Early Cretaceous in western Liaoning, Northeast China

2009 ◽  
Vol 47 (2) ◽  
pp. 93-102 ◽  
Author(s):  
Shuang-Xing GUO ◽  
Jin-Geng SHA ◽  
Li-Zeng BIAN ◽  
Yin-Long QIU
Keyword(s):  
Early Cretaceous ◽  
Northeast China ◽  
Western Liaoning

Ordosemys leios, n.gen., n.sp., a new turtle from the Early Cretaceous of the Ordos Basin, Inner Mongolia

1993 ◽  
Vol 30 (10) ◽  
pp. 2128-2138 ◽  
Author(s):  
Donald B. Brinkman ◽  
Jiang-Hua Peng
Keyword(s):  
Early Cretaceous ◽  
Inner Mongolia ◽  
Cervical Vertebrae ◽  
Ordos Basin ◽  
Sister Group ◽  
Sister Group Relationship ◽  
Articular Surfaces ◽  
Caudal Vertebrae ◽  
The Ordos Basin

Ordosemys leios, n.gen., n.sp., from the Early Cretaceous Luohandong Formation, Zhidan Group, Ordos Basin, Inner Mongolia, is a primitive aquatic turtle with a reduced, fenestrated plastron. It shares with the members of the Centrocryptodira the presence of well-formed articular surfaces on the cervical and caudal vertebrae. Within the Centrocryptodira, characters of the cervical vertebrae suggest it is more closely related to the Polycryptodira than is the Meiolaniidae. Ordosemys shares with the Chelydridae the presence of two procoelous anterior caudals, but this character may be primitive for the Polycryptodira. Characters of the basicranial region of the braincase shared by Ordosemys and the Chelonioidea support a sister-group relationship between these two taxa, but a sister-group relationship between Ordosemys and the Polycryptodira is more strongly supported by characters shared by the Chelonioidea and other members of the Polycryptodira.

Numerical Analysis of Branch Mechanical Response to Loading

2019 ◽  
Vol 45 (4) ◽  
Author(s):  
Barbora Vojáčková ◽  
Jan Tippner ◽  
Petr Horáček ◽  
Luděk Praus ◽  
Václav Sebera ◽  
...  
Keyword(s):  
Finite Element ◽  
Cross Sections ◽  
Mechanical Response ◽  
Mechanical Analysis ◽  
Beam Deflection ◽  
Design System ◽  
Elliptical Cross ◽  
Static Mechanical ◽  
The Difference ◽  
Tree Uprooting

Failure of a tree can be caused by a stem breakage, tree uprooting, or branch failure. While the pulling test is used for assessing the first two cases, there is no device-supported method to assess branch failure. A combination of the optical technique, pulling test, and deflection curve analysis could provide a device-supported tool for this kind of assessment. The aim of the work was to perform a structural analysis of branch response to static mechanical loading. The analyses were carried out by finite element simulations in ANSYS using beam tapered elements of elliptical cross-sections. The numerical analyses were verified by the pulling test combined with a sophisticated optical assessment of deflection evaluation. The Probabilistic Design System was used to find the parameters that influence branch mechanical response to loading considering the use of cantilever beam deflection for stability analysis. The difference in the branch’s deflection between the simulation and the experiment is 0.5% to 26%. The high variability may be explained by the variable modulus of the elasticity of branches. The finite element (FE) sensitivity analysis showed a higher significance of geometry parameters (diameter, length, tapering, elliptical cross-section) than material properties (elastic moduli). The anchorage rotation was found to be significant, implying that this parameter may affect the outcome in mechanical analysis of branch behavior. The branch anchorage can influence the deflection of the whole branch, which should be considered in stability assessment.

Stresses and Deformations of Toroidal Shells of Elliptical Cross Section: With Applications to the Problems of Bending of Curved Tubes and of the Bourdon Gage

1952 ◽  
Vol 19 (1) ◽  
pp. 37-48
Author(s):  
R. A. Clark ◽  
T. I. Gilroy ◽  
E. Reissner
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Practical Interest ◽  
Closed Shell ◽  
Open Shell ◽  
Elliptical Cross Section ◽  
Axially Symmetric ◽  
Elliptical Cross ◽  
Two Parameters ◽  
Toroidal Shells

Abstract This paper is concerned with the application of the theory of thin shells to several problems for toroidal shells with elliptical cross section. These problems are as follows: (a) Closed shell subjected to uniform normal wall pressure. (b) Open shell subjected to end bending moments. (c) Combination of the results for the first and second problems in such a way as to obtain results for the stresses and deformations in Bourdon tubes. In all three problems the distribution of stresses is axially symmetric but only in the first problem are the displacements axially symmetric. The magnitude of stresses and deformations for given loads depends in all three problems on the magnitude of the two parameters bc/ah and b/c where b and c are the semiaxes of the elliptical section, a is the distance of the center of the section from the axis of revolution, and h is the thickness of the wall of the shell. For sufficiently small values of bc/ah trigonometric series solutions are obtained. For sufficiently large values of bc/ah asymptotic solutions are obtained. Numerical results are given for various quantities of practical interest as a function of bc/ah for the values 2, 1, 1/2, 1/4 of the semiaxes ratio b/c. It is suggested that the analysis be extended to still smaller values of b/c and to cross sections other than elliptical.

Genesis of the Wurinitu W-Mo deposit, Inner Mongolia, northeast China: Constraints from geology, fluid inclusions and isotope systematics

2018 ◽  
Vol 94 ◽  
pp. 367-382 ◽  
Author(s):  
Yin-Hong Wang ◽  
Fang-Fang Zhang ◽  
Jia-Jun Liu ◽  
Chun-Ji Xue ◽  
Zhao-Chong Zhang
Keyword(s):  
Fluid Inclusions ◽  
Inner Mongolia ◽  
Northeast China ◽  
Isotope Systematics
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