scholarly journals Bone Graft Substitutes in Maxillofacial Reconstruction - Structural and Biomechanical Perspectives

2021 ◽  
Vol 10 (31) ◽  
pp. 2369-2372
Author(s):  
Shyam Sundar S. ◽  
Sahith Kumar Shetty
Keyword(s):  
Paradigm Shift ◽  
Multidisciplinary Approach ◽  
Three Dimensional ◽  
Recent Past ◽  
Skeletal Defect ◽  
Skeletal Defects ◽  
Bone Graft Substitutes ◽  
Stable Reconstruction ◽  
Physical And Chemical ◽  
Insight Into

Reconstruction of a maxillofacial skeletal defect in the recent past has witnessed a paradigm shift in the process of treatment planning. It has now become a collaboration between the surgeon and the bioengineer to provide a customised stable reconstruction. Understanding maxillofacial skeleton from an architectural and biomechanical perspective would not only guide the surgeon in planning a reconstruction but also the bioengineer to select the biomaterial and design an ideal reconstruction. This paper intended to provide an insight into scientific concepts which needed to be considered during the designing of biomaterials for reconstruction of maxillofacial skeletal defects. Any object in the world, from a mechanical perspective is seen only as a material of varying physical and chemical (organic / inorganic) properties dwelling in a dynamic three-dimensional environment. Bone continuously has been re-modelling by adapting to the dynamic loading environment through an established force distribution pattern of equilibrium. 1 Hence, for a patient requiring reconstruction of defects of varying dimensions within the craniomaxillofacial skeleton, its architectural complexity should be seen from both the surgeon’s and bioengineer’s perspective. Such multidisciplinary approach would provide a customized comprehensive reconstructive and rehabilitative solution.

Structure and function of neural networks in the retina

1988 ◽  
Vol 46 ◽  
pp. 26-27
Author(s):  
Peter Sterling
Keyword(s):  
Ganglion Cells ◽  
Three Dimensional ◽  
Structure And Function ◽  
Synaptic Connections ◽  
Visual Axis ◽  
One Dimensional ◽  
Cat Retina ◽  
Ultrathin Sections ◽  
And Function ◽  
Insight Into

The synaptic connections in cat retina that link photoreceptors to ganglion cells have been analyzed quantitatively. Our approach has been to prepare serial, ultrathin sections and photograph en montage at low magnification (˜2000X) in the electron microscope. Six series, 100-300 sections long, have been prepared over the last decade. They derive from different cats but always from the same region of retina, about one degree from the center of the visual axis. The material has been analyzed by reconstructing adjacent neurons in each array and then identifying systematically the synaptic connections between arrays. Most reconstructions were done manually by tracing the outlines of processes in successive sections onto acetate sheets aligned on a cartoonist's jig. The tracings were then digitized, stacked by computer, and printed with the hidden lines removed. The results have provided rather than the usual one-dimensional account of pathways, a three-dimensional account of circuits. From this has emerged insight into the functional architecture.

Custom Presurgical Planning for Midfacial Reconstruction

2020 ◽  
Vol 36 (06) ◽  
pp. 696-702
Author(s):  
Nolan B. Seim ◽  
Enver Ozer ◽  
Sasha Valentin ◽  
Amit Agrawal ◽  
Mead VanPutten ◽  
...  
Keyword(s):  
Multidisciplinary Approach ◽  
Functional Performance ◽  
Three Dimensional ◽  
Free Tissue Transfer ◽  
Long Term Effects ◽  
Presurgical Planning ◽  
Dental Rehabilitation ◽  
Midface Reconstruction ◽  
Reconstructive Algorithm

AbstractResection and reconstruction of midface involve complex ablative and reconstructive tools in head and oncology and maxillofacial prosthodontics. This region is extraordinarily important for long-term aesthetic and functional performance. From a reconstructive standpoint, this region has always been known to present challenges to a reconstructive surgeon due to the complex three-dimensional anatomy, the variable defects created, combination of the medical and dental functionalities, and the distance from reliable donor vessels for free tissue transfer. Another challenge one faces is the unique features of each individual resection defect as well as individual patient factors making each preoperative planning session and reconstruction unique. Understanding the long-term effects on speech, swallowing, and vision, one should routinely utilize a multidisciplinary approach to resection and reconstruction, including head and neck reconstructive surgeons, prosthodontists, speech language pathologists, oculoplastic surgeons, dentists, and/or craniofacial teams as indicated and with each practice pattern. With this in mind, we present our planning and reconstructive algorithm in midface reconstruction, including a dedicated focus on dental rehabilitation via custom presurgical planning.

Incorporation of spatial variability in modeling non-point source groundwater nitrate pollution

1996 ◽  
Vol 33 (4-5) ◽  
pp. 233-240 ◽  
Author(s):  
F. S. Goderya ◽  
M. F. Dahab ◽  
W. E. Woldt ◽  
I. Bogardi
Keyword(s):  
Spatial Variability ◽  
Point Source ◽  
Three Dimensional ◽  
Nitrate Contamination ◽  
Geostatistical Simulation ◽  
Chemical Measurements ◽  
Spatially Distributed ◽  
Potential Benefits ◽  
Zone Modeling ◽  
Physical And Chemical

A methodology for incorporation of spatial variability in modeling non-point source groundwater nitrate contamination is presented. The methodology combines geostatistical simulation and unsaturated zone modeling for estimating the amount of nitrate loading to groundwater. Three dimensional soil nitrogen variability and 2-dimensional crop yield variability are used in quantifying potential benefits of spatially distributed nitrogen input. This technique, in combination with physical and chemical measurements, is utilized as a means of illustrating how the spatial statistical properties of nitrate leaching can be obtained for different scenarios of fixed and variable rate nitrogen applications.

Antibacterial and Anti-Biofilm Biosynthesised Silver and Gold Nanoparticles for Medical Applications: Mechanism of Action, Toxicity and Current Status

2020 ◽  
Vol 17 (2) ◽  
pp. 88-100 ◽  
Author(s):  
Sundos Suleman Ismail Abdalla ◽  
Haliza Katas ◽  
Fazren Azmi ◽  
Mohd Fauzi Mh Busra
Keyword(s):  
Gold Nanoparticles ◽  
Synthesis Method ◽  
Chemical Characterization ◽  
Current Status ◽  
Silver And Gold Nanoparticles ◽  
Physical And Chemical Characterization ◽  
Biosynthesized Agnps ◽  
Physical And Chemical ◽  
Insight Into ◽  
Bio Synthesis

Fast progress in nanoscience and nanotechnology has contributed to the way in which people diagnose, combat, and overcome various diseases differently from the conventional methods. Metal nanoparticles, mainly silver and gold nanoparticles (AgNPs and AuNPs, respectively), are currently developed for many applications in the medical and pharmaceutical area including as antibacterial, antibiofilm as well as anti-leshmanial agents, drug delivery systems, diagnostics tools, as well as being included in personal care products and cosmetics. In this review, the preparation of AgNPs and AuNPs using different methods is discussed, particularly the green or bio- synthesis method as well as common methods used for their physical and chemical characterization. In addition, the mechanisms of the antimicrobial and anti-biofilm activity of AgNPs and AuNPs are discussed, along with the toxicity of both nanoparticles. The review will provide insight into the potential of biosynthesized AgNPs and AuNPs as antimicrobial nanomaterial agents for future use.

scholarly journals Changing landscapes: Gay men in the west and northwest of Ireland

Sexualities ◽  
2020 ◽  
pp. 136346072098169
Author(s):  
Aidan McKearney
Keyword(s):  
Gay Men ◽  
Social Rights ◽  
Irish Society ◽  
Recent Past ◽  
Same Sex ◽  
Lgbt People ◽  
The Many ◽  
Northwest Region ◽  
The Impact ◽  
Insight Into

This article focuses on the experiences of gay men in the rural west and northwest region of Ireland, during a period of transformational social and political change in Irish society. These changes have helped facilitate new forms of LGBTQI visibility, and local radicalism in the region. Same-sex weddings, establishment of rural LGBT groups and marching under an LGBT banner at St Patricks Day parades would have been unthinkable in the recent past; but they are now becoming a reality. The men report continuing challenges in their lives as gay men in the nonmetropolitan space, but the emergence of new visibility, voice and cultural acceptance of LGBT people is helping change their lived experiences. The study demonstrates the impact of local activist LGBT citizens. Through their testimonies we can gain an insight into the many, varied and interwoven factors that have interplayed to create the conditions necessary for the men to: increasingly define themselves as gay to greater numbers of people in their localities; to embrace greater visibility and eschew strategies of silence; and aspire to a host of legal, political, cultural and social rights including same-sex marriage. Organic forms of visibility and local radicalism have emerged in the region and through an analysis of their testimonies we can see how the men continue to be transformed by an ever-changing landscape.

scholarly journals Completely non-fused electron acceptor with 3D-interpenetrated crystalline structure enables efficient and stable organic solar cell

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Lijiao Ma ◽  
Shaoqing Zhang ◽  
Jincheng Zhu ◽  
Jingwen Wang ◽  
Junzhen Ren ◽  
...  
Keyword(s):  
Organic Solar Cell ◽  
Low Cost ◽  
Three Dimensional ◽  
Molecular Geometry ◽  
Interpenetrating Network ◽  
Fused Ring ◽  
Molecule Design ◽  
End Capping ◽  
Conversion Efficiencies ◽  
Insight Into

AbstractNon-fullerene acceptors (NFAs) based on non-fused conjugated structures have more potential to realize low-cost organic photovoltaic (OPV) cells. However, their power conversion efficiencies (PCEs) are much lower than those of the fused-ring NFAs. Herein, a new bithiophene-based non-fused core (TT-Pi) featuring good planarity as well as large steric hindrance was designed, based on which a completely non-fused NFA, A4T-16, was developed. The single-crystal result of A4T-16 reveals that a three-dimensional interpenetrating network can be formed due to the compact π–π stacking between the adjacent end-capping groups. A high PCE of 15.2% is achieved based on PBDB-TF:A4T-16, which is the highest value for the cells based on the non-fused NFAs. Notably, the device retains ~84% of its initial PCE after 1300 h under the simulated AM 1.5 G illumination (100 mW cm−2). Overall, this work provides insight into molecule design of the non-fused NFAs from the aspect of molecular geometry control.

Rethinking bibliographic utilities for library consortia

2020 ◽  
Vol 37 (8) ◽  
pp. 7-9
Author(s):  
Israel Odede
Keyword(s):  
Literature Review ◽  
Paradigm Shift ◽  
Design Methodology ◽  
Distributed Network ◽  
Network Resources ◽  
Content Type ◽  
Library Consortia ◽  
Individual Ownership ◽  
Insight Into

Purpose The paper aims to critically examine the bibliographic utility as a roadmap to increase library consortia and provide an insight into a new library consortia strategy that integrates librarians into a system of sharing both resources and knowledge. Design/methodology/approach This study adopted a literature review approach with a focus on bibliographic utility as a necessary prerequisite for effective library consortia, which is a paradigm shift from the concept of individual ownership to a collective access of distributed network resources and knowledge. Findings The reviewed literature indicated that significant bibliographic utilities and integrated library systems are factors that shaped and developed consortia activities in libraries. Originality/value The bibliographic utility has limited literature, and a few published scholarly studies have combined bibliographic utility and library consortia as strategies to share resources and knowledge

scholarly journals The distribution of myosin II in Dictyostelium discoideum slug cells.

1991 ◽  
Vol 115 (5) ◽  
pp. 1267-1274 ◽  
Author(s):  
S Eliott ◽  
P H Vardy ◽  
K L Williams
Keyword(s):  
Cell Motility ◽  
Dictyostelium Discoideum ◽  
Immunofluorescence Microscopy ◽  
Molecular Genetic ◽  
Myosin Ii ◽  
Three Dimensional ◽  
Homogeneous Distribution ◽  
Multicellular Development ◽  
Insight Into

While the role of myosin II in muscle contraction has been well characterized, less is known about the role of myosin II in non-muscle cells. Recent molecular genetic experiments on Dictyostelium discoideum show that myosin II is necessary for cytokinesis and multicellular development. Here we use immunofluorescence microscopy with monoclonal and polyclonal antimyosin antibodies to visualize myosin II in cells of the multicellular D. discoideum slug. A subpopulation of peripheral and anterior cells label brightly with antimyosin II antibodies, and many of these cells display a polarized intracellular distribution of myosin II. Other cells in the slug label less brightly and their cytoplasm displays a more homogeneous distribution of myosin II. These results provide insight into cell motility within a three-dimensional tissue and they are discussed in relation to the possible roles of myosin II in multicellular development.

Analysis of SiC CVD Growth in a Horizontal Hot-Wall Reactor by Experiment and 3D Modelling

2007 ◽  
Vol 556-557 ◽  
pp. 61-64
Author(s):  
Y. Shishkin ◽  
Rachael L. Myers-Ward ◽  
Stephen E. Saddow ◽  
Alexander Galyukov ◽  
A.N. Vorob'ev ◽  
...  
Keyword(s):  
Growth Rate ◽  
Growth Process ◽  
Three Dimensional ◽  
Chemical Species ◽  
3D Modelling ◽  
Complete Model ◽  
Cvd Growth ◽  
Dimensional Simulation ◽  
Insight Into ◽  
Hot Zone

A fully-comprehensive three-dimensional simulation of a CVD epitaxial growth process has been undertaken and is reported here. Based on a previously developed simulation platform, which connects fluid dynamics and thermal temperature profiling with chemical species kinetics, a complete model of the reaction process in a low pressure hot-wall CVD reactor has been developed. Close agreement between the growth rate observed experimentally and simulated theoretically has been achieved. Such an approach should provide the researcher with sufficient insight into the expected growth rate in the reactor as well as any variations in growth across the hot zone.

Archaeal biofilms: widespread and complex

2013 ◽  
Vol 41 (1) ◽  
pp. 393-398 ◽  
Author(s):  
Sabrina Fröls
Keyword(s):  
Biofilm Formation ◽  
Extracellular Polymeric Substances ◽  
Bacterial Species ◽  
Surface Adhesion ◽  
Form Complex ◽  
Abiotic Surfaces ◽  
Archaeal Species ◽  
Physical And Chemical ◽  
Insight Into ◽  
Mixed Communities

Biofilms or multicellular structures become accepted as the dominant microbial lifestyle in Nature, but in the past they were only studied extensively in bacteria. Investigations on archaeal monospecies cultures have shown that many archaeal species are able to adhere on biotic and abiotic surfaces and form complex biofilm structures. Biofilm-forming archaea were identified in a broad range of extreme and moderate environments. Natural biofilms observed are mostly mixed communities composed of archaeal and bacterial species of various abundances. The physiological functions of the archaea identified in such mixed communities suggest a significant impact on the biochemical cycles maintaining the flow and recycling of the nutrients on earth. Therefore it is of high interest to investigate the characteristics and mechanisms underlying the archaeal biofilm formation. In the present review, I summarize and discuss the present investigations of biofilm-forming archaeal species, i.e. their diverse biofilm architectures in monospecies or mixed communities, the identified EPSs (extracellular polymeric substances), archaeal structures mediating surface adhesion or cell–cell connections, and the response to physical and chemical stressors implying that archaeal biofilm formation is an adaptive reaction to changing environmental conditions. A first insight into the molecular differentiation of cells within archaeal biofilms is given.

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