scholarly journals Molecular Packing in Network-Forming Collagens

2003 ◽  
Vol 3 ◽  
pp. 558-577 ◽  
Author(s):  
Carlo Knupp ◽  
John M. Squire
Keyword(s):  
Structural Characteristics ◽  
Structure And Function ◽  
Molecular Packing ◽  
Abundant Protein ◽  
Type Iv ◽  
Different Types ◽  
Collagen Molecules ◽  
Weight Structure ◽  
Egg Case ◽  
And Function

Collagen is the most abundant protein among vertebrates and occurs in virtually all multicellular animals. Collagen molecules are classified into 21 different types and differ in their sequence, weight, structure, and function, but they can be broadly subdivided into families. Type IV, VI, VIII, X, and dogfish egg case collagens belong to the network-forming family. Here, we summarise what is known about the way these collagen molecules pack to form networks. In addition the main structural characteristics of the network-forming collagens are compared and discussed.

Influence fast or later: two types of influencers in social networks

2021 ◽  
Author(s):  
Fang Zhou ◽  
Chang Su ◽  
Shuqi Xu ◽  
Linyuan Lü
Keyword(s):  
Final Stage ◽  
Early Stage ◽  
Large Fraction ◽  
Structure And Function ◽  
Spreading Process ◽  
Spreading Effect ◽  
Local Structures ◽  
Different Types ◽  
Small Set ◽  
And Function

Abstract In real-world networks, there usually exist a small set of nodes that play an important role in the structure and function of networks. Those vital nodes can influence most other nodes in the network via a spreading process. While most of the existing works focused on vital nodes that can maximize the spreading size in the final stage, which we call final influencers, recent work proposed the idea of fast influencers, which emphasizes nodes’ spreading capacity at the early stage. Despite the recent surge of efforts in identifying these two types of influencers in networks, there remained limited research on untangling the differences between fast influencers and final influencers. In this paper, we first distinguish the two types of influencers: fast-only influencers and final-only influencers. The former is defined as individuals who can achieve a high spreading effect at the early stage but lose their superiority in the final stage, and the latter are those individuals that fail to exhibit a prominent spreading performance at the early stage but influence a large fraction of nodes at the final stage. Further experiments based on eight empirical datasets, we reveal the key differences between the two types of influencers concerning their spreading capacity and the local structures. We also analyze how network degree assortativity influences the fraction of the proposed two types of influencers. The results demonstrate that with the increase of degree assortativity, the fraction of the fast-only influencers decreases, which indicates that more fast influencers tend to keep their superiority at the final stage. Our study provides insights into the differences and evolution of different types of influencers and has important implications for various empirical applications, such as advertisement marketing, and epidemic suppressing.

Regulation of sperm motility at the axonemal level

1995 ◽  
Vol 7 (4) ◽  
pp. 847 ◽  
Author(s):  
C Gagnon
Keyword(s):  
Direct Action ◽  
Mammalian Species ◽  
Basic Structure ◽  
Structure And Function ◽  
Structural Components ◽  
Long Period ◽  
Different Types ◽  
Radial Spokes ◽  
Dynein Arms ◽  
And Function

With very few exceptions, the basic structure of the 9+2 axoneme has been well preserved over a very long period of evolution from protozoa to mammais. This stability indicates that the basic structural components of the axoneme visible by electron microscopy, as well as most of the other unidentified components, have withstood the passage of time. It also means that components of the 9+2 axoneme have sufficient diversity in function to accommodate the various types of motility patterns encountered in different species of flagella. Several of the 200 polypeptides that constitute the axoneme have been identified as components of the dynein arms, radial spokes etc. but many more remain to be identified and their function(s) remain to be determined. Because this review deals with the regulation of flagellar movement at the axonemal level, it does not include regulation of flagella by extracellular factors unless these factors have a direct action on axonemal components. In this context, it is very important firstly to understand the structural components of the axoneme and how they influence and regulate axonemal movement. Different primitive organisms are mentioned in this review since major breakthroughs in our understanding of how an axoneme generates different types of movement have been made through their study. Despite some variations in structure and function of axonemal components, the basic mechanisms involved in the regulation of flagella from Chlamydomonas or sea urchin spermatozoa should also apply to the more evolved mammalian species, including human spermatozoa.

Individual Differences Among Users

2011 ◽  
pp. 1-24 ◽  
Author(s):  
Madeleine Keehner ◽  
Peter Khooshabeh ◽  
Mary Hegarty
Keyword(s):  
Individual Differences ◽  
Three Dimensional ◽  
Structure And Function ◽  
Science Literature ◽  
Interactive Behavior ◽  
Different Types ◽  
Interactive Visualizations ◽  
Cognitive Benefits ◽  
Sophisticated User ◽  
And Function

This chapter examines human factors associated with using interactive three-dimensional (3D) visualizations. Virtual representations of anatomical structure and function, often with sophisticated user control capabilities, are growing in popularity in medicine for education, training, and simulation. This chapter reviews the cognitive science literature and introduces issues such as theoretical ideas related to using interactive visualizations, different types and levels of interactivity, effects of different kinds of control interfaces, and potential cognitive benefits of these tools. The authors raise the question of whether all individuals are equally capable of using 3D visualizations effectively, focusing particularly on two variables: (1) individual differences in spatial abilities, and (2) individual differences in interactive behavior. The chapter draws together findings from the authors’ own studies and from the wider literature, exploring recent insights into how individual differences among users can impact the effectiveness of different types of external visualizations for different kinds of tasks. The chapter offers recommendations for design, such as providing transparent affordances to support users’ meta-cognitive understanding, and employing personalization to complement the capabilities of different individuals. Finally, the authors suggest future directions and approaches for research, including the use of methodology such as needs analysis and contextual enquiry to better understand the cognitive processes and capacities of different kinds of users.

Design of Drawer-Combined Condiment Container

2014 ◽  
Vol 602-605 ◽  
pp. 499-502
Author(s):  
Yan Yuan ◽  
Le Cao
Keyword(s):  
Material Selection ◽  
Structure And Function ◽  
Design Methods ◽  
Space Saving ◽  
Different Types ◽  
And Function

A drawer-combined condiment container was designed, and the design methods and steps were illustrated from four aspects, including the structure and function, material selection, dimensioning, modeling and decoration. With the integrated storage and independent sealing of different types of condiment, as well as the pickup of improved fluid condiment, it is characterized by cleanliness, convenience in application, space-saving and reusable features when compared to the like product. Therefore, it is of application and promotion value in the packing container design and related industries.

Macromolecular constituents of basement membranes: a review of current knowledge on their structure and function

1983 ◽  
Vol 61 (8) ◽  
pp. 942-948 ◽  
Author(s):  
Paul G. Scott
Keyword(s):  
Type Iv Collagen ◽  
Current Knowledge ◽  
Heparan Sulphate ◽  
Structural Features ◽  
Structure And Function ◽  
Basement Membranes ◽  
Type Iv ◽  
Type V ◽  
And Function ◽  
Additional Form

Macromolecules which appear to be integral constituents of basement membranes include type IV collagen, the glycoprotein laminin, and heparan sulphate proteoglycan. Another glycoprotein, fibronectin, may occupy an intermediate position between some lining cells and their basement membranes but is not, however, restricted to this location. An additional form of collagen, genetic type V which differs significantly from type IV collagen in structure, appears to be associated with some basement membranes, possibly linking them to underlying connective tissue. The main structural features of each of these macromolecules, as presently understood, are reviewed here as a background to the experimental papers in this "mini-symposium."

scholarly journals Students’ understanding of the cell and cellular structures

2021 ◽  
Vol 17 (2) ◽  
pp. 225-241
Author(s):  
Mai Lill Suhr Lunde ◽  
Tone Fredsvik Gregers
Keyword(s):  
Cell Biology ◽  
Cellular Structure ◽  
Structure And Function ◽  
Cellular Structures ◽  
New Knowledge ◽  
Different Types ◽  
Eighth Grade Students ◽  
Biology Instruction ◽  
And Function ◽  
Systemic View

This study aimed to investigate Norwegian eighth-grade students’ preconceptions of cells, the development of their understanding of cellular structure and function during cell biology instruction, and their understanding of the cell as a system. We conducted pre- and posttests including drawings, images and statements with 28 students. Our findings indicate that most students had a simplified view of cells prior to instruction but developed significant knowledge about cellular structures and different types of cells during instruction. However, several misconceptions arose, and some students seemed to alter their correct preconceptions. This suggests that teachers need to address misconceptions during instruction and support integration of students’ previous and new knowledge. Additionally, we suggest that focusing on numerous structures and cells from different organisms confuses students and complicates the process of achieving a systemic view of the cell.

scholarly journals Hemicentin mediated type IV collagen assembly strengthens juxtaposed basement membrane linkage

2021 ◽  
Author(s):  
Claire A Gianakas ◽  
Daniel P Keeley ◽  
William Ramos-Lewis ◽  
Kieop Park ◽  
Ranjay Jayadev ◽  
...  
Keyword(s):  
Basement Membrane ◽  
Type Iv Collagen ◽  
Fluorescent Proteins ◽  
Structure And Function ◽  
Egg Laying ◽  
Matrix Proteins ◽  
Type Iv ◽  
Seam Cell ◽  
Specialized Form ◽  
And Function

Basement membrane (BM) matrices surround and separate most tissues. However, through poorly understood mechanisms, BMs of adjacent tissues can also stably link to support organ structure and function. Using endogenous knock-in fluorescent proteins, conditional RNAi, optogenetics, and quantitative live imaging, we identified matrix proteins mediating a BM linkage (B-LINK) between the uterine utse and epidermal seam cell BMs in Caenorhabditis elegans that supports the uterus during egg-laying. We found that hemicentin is secreted by the utse and promotes fibulin-1 assembly to jointly initiate the B-LINK. During egg-laying, however, both proteins decline in levels and are not required for B-LINK maintenance. Instead, we discovered that hemicentin also promotes type IV collagen assembly, which accumulates to high levels during egg-laying and sustains the B-LINK during the mechanically active egg-laying period. This work reveals mechanisms underlying BM-BM connection maturation and identifies a crucial function for hemicentin and fibulin-1 in initiating attachment and type IV collagen in strengthening this specialized form of tissue linkage.

scholarly journals Evaluation of left ventricular systolic function in patients with different types of ischemic heart disease by two-dimensional speckle tracking imaging

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Xing Xing ◽  
Dan Li ◽  
Shaomin Chen ◽  
Lingli Wang ◽  
Zhaoping Li ◽  
...  
Keyword(s):  
Systolic Function ◽  
Left Ventricular Systolic Function ◽  
Left Ventricular ◽  
Structure And Function ◽  
Control Group ◽  
Speckle Tracking Imaging ◽  
Ventricular Systolic Function ◽  
Different Types ◽  
And Function ◽  
Conventional Echocardiography

Abstract Background The purpose of this study was to evaluate left ventricular systolic function in patients with different types of ischemic heart disease using two-dimensional speckle tracking imaging (2D-STI). Methods We retrospectively studied patients who were admitted to Peking University Third Hospital from January 2011 to December 2017 due to chest tightness and chest pain. Two hundred forty-two patients were divided into control group, CMD group and obstructive CAD group. The main coronary artery stenosis was confirmed by coronary angiography or coronary computed tomography and coronary flow reserve (CFR) in patients was measured by transthoracic Doppler echocardiography. Left ventricular strain and strain rate (SR) measured by 2D-STI. Cardiac structure and function were measured by conventional echocardiography. Results Conventional echocardiography showed that there was no significant difference in cardiac structure and function among the three groups (P > 0.05). Moreover, the longitudinal strain (LS) of each ventricular wall in CMD group was notably lower than that in control group (P < 0.01). In addition, global longitudinal SR and longitudinal SR in CMD group and obstructive CAD group were obviously lower than those in control group (P < 0.01). GLS, endocardial LS and epicardial LS were negatively correlated with CFR (P < 0.01). Conclusions Early left ventricular systolic dysfunction was found in patients with CMD and patients with obstructive CAD, with similar degree. CFR is an independent influencing factor of GLS. GLS and stratified LS have certain diagnostic value for CMD.

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