scholarly journals Construction patterns of birds’ nests provide insight into nest-building behaviours

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3010 ◽  
Author(s):  
Lucia Biddle ◽  
Adrian M. Goodman ◽  
D. Charles Deeming
Keyword(s):  
Structural Analysis ◽  
Structural Properties ◽  
Biomechanical Properties ◽  
Nest Building ◽  
Construction Process ◽  
Side Walls ◽  
Materials Used ◽  
Insight Into ◽  
Pyrrhula Pyrrhula ◽  
Different Parts

Previous studies have suggested that birds and mammals select materials needed for nest building based on their thermal or structural properties, although the amounts or properties of the materials used have been recorded for only a very small number of species. Some of the behaviours underlying the construction of nests can be indirectly determined by careful deconstruction of the structure and measurement of the biomechanical properties of the materials used. Here we examined this idea in an investigation of Bullfinch (Pyrrhula pyrrhula) nests as a model for open-nesting songbird species that construct a “twig” nest, and tested the hypothesis that materials in different parts of nests serve different functions. The quantities of materials present in the nest base, sides and cup were recorded before structural analysis. Structural analysis showed that the base of the outer nests were composed of significantly thicker, stronger and more rigid materials compared to the side walls, which in turn were significantly thicker, stronger and more rigid than materials used in the cup. These results suggest that the placement of particular materials in nests may not be random, but further work is required to determine if the final structure of a nest accurately reflects the construction process.

Semantic And Structural Properties Of The Banking And Financial Terminology Of The Uzbek Language

2020 ◽  
Vol 2 (08) ◽  
pp. 610-617
Author(s):  
Ekaterina Turakulovna Shirinova
Keyword(s):  
Structural Analysis ◽  
Structural Properties ◽  
Human Factor

This article discusses information on the study of terminology in Uzbek and world linguistics. Thematic grouping of banking and financial terms, which play an important role in Uzbek language vocabulary, is considered. The author gives the criteria for the distribution of terms into thematic groups, their peculiar properties examples to substantiate the hypothesis. The paradigmatic relations between the terms of this sphere are indicated. A structural analysis of the banking and financial terms of the Uzbek language is carried out.  On the basis of the anthropocentric approach, the role of the human factor in the banking and financial terminology of the Uzbek language is studied. Cognitive metaphors that exist in the terminology are considered.

scholarly journals Insight into the origin of SARS-CoV-2 through structural analysis of receptor recognition: a molecular simulation study

RSC Advances ◽  
2021 ◽  
Vol 11 (15) ◽  
pp. 8718-8729
Author(s):  
Jixue Sun ◽  
Meijiang Liu ◽  
Na Yang
Keyword(s):  
Molecular Dynamics ◽  
Structural Analysis ◽  
Molecular Dynamics Simulations ◽  
Molecular Simulation ◽  
Simulation Study ◽  
Receptor Recognition ◽  
Dynamics Simulations ◽  
Insight Into

The origin of SARS-CoV-2 through structural analysis of receptor recognition was investigated by molecular dynamics simulations.

scholarly journals Structural analysis of cross α-helical nanotubes provides insight into the designability of filamentous peptide nanomaterials

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Fengbin Wang ◽  
Ordy Gnewou ◽  
Charles Modlin ◽  
Leticia C. Beltran ◽  
Chunfu Xu ◽  
...  
Keyword(s):  
Structural Analysis ◽  
Synthetic Peptide ◽  
Quaternary Structure ◽  
De Novo ◽  
Rational Approach ◽  
Lateral Interactions ◽  
Protein Assemblies ◽  
Self Assembling ◽  
Arginine Residues ◽  
Insight Into

AbstractThe exquisite structure-function correlations observed in filamentous protein assemblies provide a paradigm for the design of synthetic peptide-based nanomaterials. However, the plasticity of quaternary structure in sequence-space and the lability of helical symmetry present significant challenges to the de novo design and structural analysis of such filaments. Here, we describe a rational approach to design self-assembling peptide nanotubes based on controlling lateral interactions between protofilaments having an unusual cross-α supramolecular architecture. Near-atomic resolution cryo-EM structural analysis of seven designed nanotubes provides insight into the designability of interfaces within these synthetic peptide assemblies and identifies a non-native structural interaction based on a pair of arginine residues. This arginine clasp motif can robustly mediate cohesive interactions between protofilaments within the cross-α nanotubes. The structure of the resultant assemblies can be controlled through the sequence and length of the peptide subunits, which generates synthetic peptide filaments of similar dimensions to flagella and pili.

scholarly journals Collagen-Platelet Composites Improve the Biomechanical Properties of Healing Anterior Cruciate Ligament Grafts in a Porcine Model

2009 ◽  
Vol 37 (8) ◽  
pp. 1554-1563 ◽  
Author(s):  
Braden C. Fleming ◽  
Kurt P. Spindler ◽  
Matthew P. Palmer ◽  
Elise M. Magarian ◽  
Martha M. Murray
Keyword(s):  
Anterior Cruciate Ligament ◽  
Structural Properties ◽  
Acl Reconstruction ◽  
Porcine Model ◽  
Cruciate Ligament ◽  
Bone Allograft ◽  
Knee Laxity ◽  
Biomechanical Properties ◽  
Anterior Cruciate ◽  
Vessel Infiltration

Background The outcome of anterior cruciate ligament (ACL) reconstruction is variable, and many patients have increased joint laxity postoperatively. Hypothesis Placement of a collagen-platelet composite (CPC) around the graft at the time of ACL reconstruction decreases postoperative knee laxity and improves the structural properties of the graft compared with standard ACL reconstruction. Study Design Controlled laboratory study. Methods Thirteen immature pigs underwent unilateral ACL reconstruction with a bone–patellar tendon–bone allograft. In 6 pigs, a standard allograft was used to reconstruct the ACL. In 7 pigs, a CPC was placed around the allograft. After 15 weeks of healing, the animals were euthanized, and the anterior-posterior (AP) knee laxity and structural properties of the graft were measured. Qualitative histology of the grafts was also performed. Results The AP laxity values of the reconstructed knees, normalized to the contralateral control, were significantly reduced by 28% and 57% at 60° and 90° of knee flexion, respectively, with the addition of CPC (P <. 001). Significant improvements in the graft structural properties were also found; the normalized yield (P =. 044) and maximum failure loads (P =. 025) of the CPC group were 60% higher than the standard ACL-reconstructed group. Although cellular and vessel infiltration were observed in the grafts of both groups, regions of necrosis were present only in the standard ACL-reconstructed group. Conclusion These data demonstrate that the application of CPC at the time of ACL reconstruction improves the structural properties of the graft and reduces early AP knee laxity in the porcine model after 15 weeks of healing. Clinical Relevance Application of a CPC to an ACL graft at the time of surgery decreased knee laxity and increased the structural properties of the graft after 15 weeks of healing.

scholarly journals Analysis of biomechanical properties of tibias after bone failure and ozone treatment in rats

2020 ◽  
Vol 9 (9) ◽  
pp. e530997474
Author(s):  
Alexadre Aniceto Rodrigues ◽  
Thiago Donizeth da Silva ◽  
Evelise Aline Soares ◽  
José Antônio Dias Garcia ◽  
Flavia da Ré Guerra ◽  
...  
Keyword(s):  
Mechanical Testing ◽  
Structural Properties ◽  
Wistar Rats ◽  
Biomechanical Properties ◽  
Bone Defects ◽  
Biomechanical Analysis ◽  
Maximum Force ◽  
Ozone Treatment ◽  
Control Group ◽  
Tissue Healing

Introduction: Ozone is a potent antioxidant that acts as a precursor of various radicals, being indicated as a powerful therapy, assisting in the process of tissue healing. Objectives: The proposal of this study was to analyze material and structural properties via mechanical testing in tibias after application of ozone in bone defects produced surgically. Methods: Ten male 40-day old albino Wistar rats have been used, divided in two groups: control group and ozone group, this last one being treated with ozonized water in 25 µg/mL of concentration until the day of euthanasia. Trichotomy and longitudinal incision was conducted in the animals’ leg skin, exposing the tibia’s diaphysis of both antimers, and with help of a high rotation pen a flaw has been produced on the bone. After 60 days of surgery the animals were euthanized, and tibias were collected for biomechanical analysis. Results: The results of the biomechanical properties – structural and material – evidenced significant interactions through exposure to ozone, showing a diminished bone resistance in animals from the control group, observed by the decrease of the maximum force (N) needed to rupture the bone when compared to the value needed to break the bones of the animals from the ozone group, and the analysis of the morphometrical properties did not show any difference between both experimental groups. Conclusion: The use of ozone did not alter the morphological structures of the tibias, and the group which used ozone presented more resistance during mechanical testings, because the maximum force for the rupture of tibia was greater in this group.

scholarly journals «Шапка колмыцкая болшая» из собрания Музеев Московского Кремля

2020 ◽  
Vol 13 (5) ◽  
pp. 1184-1217
Author(s):  
Leonid A. Bobrov ◽  
◽  
Sergei P. Orlenko ◽  
Keyword(s):  
Middle Ages ◽  
Early Modern Period ◽  
17Th Century ◽  
Late Middle Ages ◽  
Central Asian ◽  
Russian State ◽  
Crown Shape ◽  
Initial Appearance ◽  
Materials Used ◽  
Insight Into

Introduction. The article explores a helmet of the last quarter of the 17th century stored in the Moscow Kremlin Museums collection and mentioned in the Armory Chamber’s documents as ‘Kalmyk shapka bolshaya’ (Russ. ‘big Kalmyk cap’; current inventory no. OР-2059). Previously, the helmet attracted the attention of artists and historians but has never been investigated in an independent scholarly study. Goals. The work seeks to describe the construction and design of the helmet, clarify the dating and attribution, reconstruct its potential original appearance. Results. Analysis of the materials used classifies the helmet as an iron object, that of the design of the crown refers it to riveted ones, and the dome crown shape clusters the item with spherocylindrical helmets. The paper specifies that the helmet is integral to the Oirat spherocylindrical helmet group (‘jug-shaped’, ‘vase-shaped’) of the Late Middle Ages and early Modern Period. Supposedly, the craftsmen to have made such helmets were inspired by Buddhist stupas (Kalm. suburgan). The construction and design features (including Buddhist symbols on the crown), as well as the insight into official documents of the Kremlin Armory make it possible to suggest that the ‘Big Kalmyk Cap’ was forged by Oirat or Southern Siberian gunsmiths for a wealthy Oirat Buddhist warrior in the 1610s – early 1680s (the earlier date is included as one to mark the beginning of the wide spread of Buddhism among Oirats). The helmet was transferred to the Armory Chamber in the mid-to-late 17th century, however no later than 1682 when it was first mentioned in official Russian state papers. In 1683–1687, the helmet was equipped with a comforter and an aventail (presumably a Central Asian-type one). Subsequently, it became a subject of restoration. In the late 19th – early 20th century at the earliest, a ringed aventail was attached to it. The comprehensive analysis of the sources available made it possible to reconstruct the likely initial appearance of the helmet. Conclusions. The ‘Big Kalmyk Cap’ is a striking sample of 17th-century Oirat helmets. It can be used as a reference benchmark in the dating and attribution of Central Asian helmets of the specified period. Culturally, the ‘Big Kalmyk Cap’ can be clustered with the most important historical relics of the ethnos.

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