Morphological description and evolutionary significance of 300 ka hominin facial bones from Hualongdong, China

2021 ◽  
Vol 161 ◽  
pp. 103052
Author(s):  
Xiujie Wu ◽  
Shuwen Pei ◽  
Yanjun Cai ◽  
Haowen Tong ◽  
Song Xing ◽  
...  
Author(s):  
G.C. Bellolio ◽  
K.S. Lohrmann ◽  
E.M. Dupré

Argopecten purpuratus is a scallop distributed in the Pacific coast of Chile and Peru. Although this species is mass cultured in both countries there is no morphological description available of the development of this bivalve except for few characterizations of some larval stages described for culture purposes. In this work veliger larvae (app. 140 pm length) were examined by the scanning electron microscope (SEM) in order to study some aspects of the organogenesis of this species.Veliger larvae were obtained from hatchery cultures, relaxed with a solution of MgCl2 and killed by slow addition of 21 glutaraldehyde (GA) in seawater (SW). They were fixed in 2% GA in calcium free artificial SW (pH 8.3), rinsed 3 times in calcium free SW, and dehydrated in a graded ethanol series. The larvae were critical point dried and mounted on double scotch tape (DST). To permit internal view, some valves were removed by slightly pressing and lifting the tip of a cactus spine wrapped with DST, The samples were coated with 20 nm gold and examined with a JEOL JSM T-300 operated at 15 KV.


Author(s):  
Xie Nianming ◽  
Ding Shaoqing ◽  
Wang Luping ◽  
Yuan Zenglin ◽  
Zhan Guolai ◽  
...  

Perhaps the data about periplasmic enzymes are obtained through biochemical methods but lack of morphological description. We have proved the existence of periplasmic bodies by electron microscope and described their ultrastructures. We hope this report may draw the attention of biochemists and mrophologists to collaborate on researches in periplasmic enzymes or periplasmic bodies with each other.One or more independent bodies may be seen in the periplasmic space between outer and inner membranes of Gram-negative bacteria, which we called periplasmic bodies. The periplasmic bodies have been found in seven species of bacteria at least, including the Pseudomonas aeroginosa. Shigella flexneri, Echerichia coli. Yersinia pestis, Campylobacter jejuni, Proteus mirabilis, Clostridium tetani. Vibrio cholerae and Brucella canis.


Ekologija ◽  
2008 ◽  
Vol 54 (4) ◽  
pp. 251-255 ◽  
Author(s):  
Gražina Stanevičiūtė ◽  
Romualda Petkevičiūtė ◽  
Valerija Kiselienė

2018 ◽  
Vol 52 (2) ◽  
pp. 265-309 ◽  
Author(s):  
R. M. Gogorev ◽  
D. A. Chudaev ◽  
V. A. Stepanova ◽  
M. S. Kulikovskiy

The present work is an attempt to summarize, systematize, supplement and clarify the terms used in morphological description of diatoms and their taxonomy (systematics). Two glossaries (Russian and English) include definitions of near 300 key terms (excluding their synonyms) and their Latin translations.


2013 ◽  
Vol 47 ◽  
pp. 68-73
Author(s):  
S. V. Volobuev

The corticioid basidiomycete Jaapia ochroleuca (Bres.) Nannf. et J. Erikss. is recorded for the first time in the European Russia from the «Bryansky Les» Nature Reserve (Bryansk Region). The taxonomic position of the species is defined briefly. Its morphological description and data on distribution and ecology are provided. The details of microscopic structure of the collected specimen are illustrated.


Author(s):  
Francisco J. Ayala ◽  
Camilo J. Cela-Conde

This chapter analyzes the transition of the hominins from the Middle Pleistocene to the Late Pleistocene. Two alternative models are explored, the “Multiregional Hypothesis” (MH) and the “Replacement Hypothesis,” and how each model evaluates the existing relationships between the taxa Homo neanderthalensis and Homo sapiens. Next is the investigation of the transitional (or “archaic,” if this grade is taken into account) exemplars found in Europe, Africa, and Asia and their evolutionary significance. In particular, the comparison between H. erectus and H. sapiens in China and Java is investigated, as the main foundation of the MH. The chapter ends with the surprising discovery of Homo floresiensis and its description and interpretations concerning its taxonomic and phylogenetic significance. The correlation between brain development and technological progress is at odds with the attribution of perforators, microblades, and fishing hooks to a hominin with a small cranial volume, similar to that of Australopithecus afarensis.


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