The gastrointestinal tracts of four Chelonia mydas hatchlings were examined at the anatomical, histological and ultrastructural level. Our results show that the gastrointestinal tract(GI) is composed by esophagus, s...The gastrointestinal tracts of four Chelonia mydas hatchlings were examined at the anatomical, histological and ultrastructural level. Our results show that the gastrointestinal tract(GI) is composed by esophagus, stomach, small intestine(SI) and large intestine(LI), and histologically of mucosa, submucosa, muscularis externa(ME) and serosa. The esophagus is marked by conical papillae lined by keratinized stratified squamous epithelium, whereas the remaining GI by simple columnar epithelium; esophageal diverticulum is absent. The stomach covered with mucous granule cells, contains cardia, fundic regions and pylorus, which are separately characterized by cardiac glands, fundic glands and pyloric glands, and have the thickest submucosa and ME of the GI. The ME of the esophagus mainly consist of one layer of circular smooth muscle whereas the rest of GI of two layers, inner circular muscle and outer longitudinal muscle. The SI is slightly longer than the LI and the GI is approximately 5.11 times of the carapace length. The SI is lined with longitudinal zigzag folds and characterized by absorptive cells with longer and denser microvilli, whereas the LI by transversal folds, goblet cells and lymphoid nodules. Only intestinal glands appear in duodenum. Endocrine cells are observed in all sections of the GI and accounted for the largest proportion in duodenum. The results demonstrate a perfect combination of the structure and function of the GI and reveal that the digestion and absorption primarily occurs in the foregut. C. mydas hatchling may prefer carnivorous diet.展开更多
A new species,Amolops pallasitatus sp.nov.is described based on specimens collected from Chentang Town,Dinggyê County,southern Tibet,China.The new species can be distinguished from other known congeners by mitoch...A new species,Amolops pallasitatus sp.nov.is described based on specimens collected from Chentang Town,Dinggyê County,southern Tibet,China.The new species can be distinguished from other known congeners by mitochondrial divergence and morphological characteristics including:(1)medium body size,SVL 70.6–72.3 mm in adult females;(2)skin smooth over the entire body;(3)absence of dorsolateral fold;(4)tympanum small,edge indistinct,less than half of eye diameter;(5)vomerine teeth in two short oblique;(6)circummarginal and transverse grooves absent on disk of the first finger;(7)presence of inner metacarpal tubercle;(8)toes fully webbed,webbing formula Ⅰ0-0^-Ⅱ0-1/2Ⅲ0-1^+Ⅳ1^+-0Ⅴ;(9)absence of outer metatarsal tubercle and tarsal glands;(10)tibiotarsal articulation of the hind limb reaches posterior corners of the eye;(11)dorsum yellow-green,with irregular dark brown blotches without margins;(12)blotches concentrated on the dorsum,less on the flanks.In morphology,Amolops pallasitatus sp.nov.is similar to A.himalayanus and A.formosus,the difference between them is length of hind limbs,web of toe and dorsal colour pattern.The systematic placement of the new species within the genus is unresolved and it is not assigned to any recognized species group,for the lack of convictive evidences.展开更多
The external morphology and internal oral features of the tadpoles of Kaloula rugifera and K. borealis are described in this paper. Similarities between these two larvae include external morphology, oral disc, interna...The external morphology and internal oral features of the tadpoles of Kaloula rugifera and K. borealis are described in this paper. Similarities between these two larvae include external morphology, oral disc, internal oral features(floor and roof), terminal mouth, lateral eyes, single midventral spiracle, absence of keratinized jaw sheaths and labial teeth, absence of lingual papillae and postnarial arena, while the body of K. rugifera is bigger than that of K. borealis at stages from 36 to 39 and the number of papillae in the buccal cavity is 12–19 and 9–16, respectively in the two species. All the similarities and differences of the two species illustrate that the tadpoles within the family Microhylidae could be attributed to assistance in clarifying a certain taxonomic treatment in Microhylidae.展开更多
The separator with excellent mechanical and thermal properties are highly required for lithium ion batteries(LIBs).Therefore,it is crucial to develop novel nanofbrous membranes with enhanced mechanical strength and th...The separator with excellent mechanical and thermal properties are highly required for lithium ion batteries(LIBs).Therefore,it is crucial to develop novel nanofbrous membranes with enhanced mechanical strength and thermal stability.In this work,the fuorinated polyimide(FPI)was synthesized and blended with polyvinylidene fuoride(PVDF)to fabricate composite nanofbrous membranes(CNMs)via electrospinning method.Benefting from the introduction of aromatic FPI,the prepared PVDF/FPI nanofbrous membranes were endowed with enhanced mechanical strength and thermal stability.When the FPI content increased from 0 to 30 wt%,the tensile strength of composite nanofbrous membranes enhanced from 1.57 to 2.30 MPa.Moreover,there are almost no dimensional shrinkage for the CNM-30 containing 30 wt%FPI after heat treatment at 160℃ for 1 h.Furthermore,the prepared CNMs show improved electrochemical performances in comparison with neat PVDF and commercial Celgard membranes.The electrolyte uptake and ionic conductivity of the CNMs could reach to 522.4% and 1.14 ms·cm^(−1),respectively.The prepared CNMs could provide an innovative and promising approach for the development and design of high-performance separators.展开更多
文摘The gastrointestinal tracts of four Chelonia mydas hatchlings were examined at the anatomical, histological and ultrastructural level. Our results show that the gastrointestinal tract(GI) is composed by esophagus, stomach, small intestine(SI) and large intestine(LI), and histologically of mucosa, submucosa, muscularis externa(ME) and serosa. The esophagus is marked by conical papillae lined by keratinized stratified squamous epithelium, whereas the remaining GI by simple columnar epithelium; esophageal diverticulum is absent. The stomach covered with mucous granule cells, contains cardia, fundic regions and pylorus, which are separately characterized by cardiac glands, fundic glands and pyloric glands, and have the thickest submucosa and ME of the GI. The ME of the esophagus mainly consist of one layer of circular smooth muscle whereas the rest of GI of two layers, inner circular muscle and outer longitudinal muscle. The SI is slightly longer than the LI and the GI is approximately 5.11 times of the carapace length. The SI is lined with longitudinal zigzag folds and characterized by absorptive cells with longer and denser microvilli, whereas the LI by transversal folds, goblet cells and lymphoid nodules. Only intestinal glands appear in duodenum. Endocrine cells are observed in all sections of the GI and accounted for the largest proportion in duodenum. The results demonstrate a perfect combination of the structure and function of the GI and reveal that the digestion and absorption primarily occurs in the foregut. C. mydas hatchling may prefer carnivorous diet.
基金supported by Ministry of Science and Technology of China (2014FY210200)The Second National Survey of Terrestrial Wildlife Resources in ChinaThe Second National Survey of Terrestrial Wildlife Resources in Tibet of China
文摘A new species,Amolops pallasitatus sp.nov.is described based on specimens collected from Chentang Town,Dinggyê County,southern Tibet,China.The new species can be distinguished from other known congeners by mitochondrial divergence and morphological characteristics including:(1)medium body size,SVL 70.6–72.3 mm in adult females;(2)skin smooth over the entire body;(3)absence of dorsolateral fold;(4)tympanum small,edge indistinct,less than half of eye diameter;(5)vomerine teeth in two short oblique;(6)circummarginal and transverse grooves absent on disk of the first finger;(7)presence of inner metacarpal tubercle;(8)toes fully webbed,webbing formula Ⅰ0-0^-Ⅱ0-1/2Ⅲ0-1^+Ⅳ1^+-0Ⅴ;(9)absence of outer metatarsal tubercle and tarsal glands;(10)tibiotarsal articulation of the hind limb reaches posterior corners of the eye;(11)dorsum yellow-green,with irregular dark brown blotches without margins;(12)blotches concentrated on the dorsum,less on the flanks.In morphology,Amolops pallasitatus sp.nov.is similar to A.himalayanus and A.formosus,the difference between them is length of hind limbs,web of toe and dorsal colour pattern.The systematic placement of the new species within the genus is unresolved and it is not assigned to any recognized species group,for the lack of convictive evidences.
基金supported by the National Natural Science Foundation of China(30470206,30870276,30970315)
文摘The external morphology and internal oral features of the tadpoles of Kaloula rugifera and K. borealis are described in this paper. Similarities between these two larvae include external morphology, oral disc, internal oral features(floor and roof), terminal mouth, lateral eyes, single midventral spiracle, absence of keratinized jaw sheaths and labial teeth, absence of lingual papillae and postnarial arena, while the body of K. rugifera is bigger than that of K. borealis at stages from 36 to 39 and the number of papillae in the buccal cavity is 12–19 and 9–16, respectively in the two species. All the similarities and differences of the two species illustrate that the tadpoles within the family Microhylidae could be attributed to assistance in clarifying a certain taxonomic treatment in Microhylidae.
基金The authors gratefully acknowledge the supports from the Emergency Support and Public Safety Scientifc Research Projects of National Advanced Functional Fiber Innovation Center(2020-fx020009)The Postgraduate Innovation Foundation of Xi’an Polytechnic University(CHX2020037)Natural Science Foundation of Education Department of Shaanxi Province(21JK0657).
文摘The separator with excellent mechanical and thermal properties are highly required for lithium ion batteries(LIBs).Therefore,it is crucial to develop novel nanofbrous membranes with enhanced mechanical strength and thermal stability.In this work,the fuorinated polyimide(FPI)was synthesized and blended with polyvinylidene fuoride(PVDF)to fabricate composite nanofbrous membranes(CNMs)via electrospinning method.Benefting from the introduction of aromatic FPI,the prepared PVDF/FPI nanofbrous membranes were endowed with enhanced mechanical strength and thermal stability.When the FPI content increased from 0 to 30 wt%,the tensile strength of composite nanofbrous membranes enhanced from 1.57 to 2.30 MPa.Moreover,there are almost no dimensional shrinkage for the CNM-30 containing 30 wt%FPI after heat treatment at 160℃ for 1 h.Furthermore,the prepared CNMs show improved electrochemical performances in comparison with neat PVDF and commercial Celgard membranes.The electrolyte uptake and ionic conductivity of the CNMs could reach to 522.4% and 1.14 ms·cm^(−1),respectively.The prepared CNMs could provide an innovative and promising approach for the development and design of high-performance separators.