CYTOOplates are high resolution glass-bottom microplates with thousands of adhesive micropatterns arrayed in each well. When cells are seeded on concave micropatterns, the distribution of controlled adhesive contacts between cells and substrate induces the reproducible polarization of the cell machinery. Cell shape, cell polarity and internal cell organization become normalized.
Standard shapes include Disc, Crossbow, H, Y and L in three sizes. A CYTOOplate Starter's featuring different geometries is ideal to identify which micropattern works best for your assay and cell line. Micropatterns are available in fibronectin coated (fluorescently labeled or not) or as ready-to-coat surfaces. Other protein coatings are available as a custom service.
Protein Contact Networks: An Emerging Paradigm in ChemistryLe Scienze Web News
Authors: Luisa Di Paola, Micol De Ruvo, Paola Paci, Daniele Santoni, and Alessandro Giuliani.
Further information:
http://www.lswn.it/en/chemistry/news/protein_contact_networks_emerging_paradigm_chemistry
Impact Assessment of the Approach of ‘Passing On The Gift’copppldsecretariat
This report presents the Heifer Project International Strategy of ‘Passing on the Gift’. It illustrates lessons learned, successful factors and benefits of of this approach.
[ Originally posted on http://www.cop-ppld.net/cop_knowledge_base ]
CYTOOplates are high resolution glass-bottom microplates with thousands of adhesive micropatterns arrayed in each well. When cells are seeded on concave micropatterns, the distribution of controlled adhesive contacts between cells and substrate induces the reproducible polarization of the cell machinery. Cell shape, cell polarity and internal cell organization become normalized.
Standard shapes include Disc, Crossbow, H, Y and L in three sizes. A CYTOOplate Starter's featuring different geometries is ideal to identify which micropattern works best for your assay and cell line. Micropatterns are available in fibronectin coated (fluorescently labeled or not) or as ready-to-coat surfaces. Other protein coatings are available as a custom service.
Protein Contact Networks: An Emerging Paradigm in ChemistryLe Scienze Web News
Authors: Luisa Di Paola, Micol De Ruvo, Paola Paci, Daniele Santoni, and Alessandro Giuliani.
Further information:
http://www.lswn.it/en/chemistry/news/protein_contact_networks_emerging_paradigm_chemistry
Impact Assessment of the Approach of ‘Passing On The Gift’copppldsecretariat
This report presents the Heifer Project International Strategy of ‘Passing on the Gift’. It illustrates lessons learned, successful factors and benefits of of this approach.
[ Originally posted on http://www.cop-ppld.net/cop_knowledge_base ]
Transforming an Existing Distribution Network Into Autonomous MICRO-GRID usin...IJERA Editor
A distribution network with renewable and fossil-based resources can be operated as a micro-grid, in autonomous or nonautonomous modes. Autonomous operation of a distribution network requires cautious planning. In this context, a detailed methodology to develop a sustainable autonomous micro-grid is presented in this paper. The proposed methodology suggests novel sizing and siting strategies for distributed generators and structural modifications for autonomous micro-grids. This paper introduces the Particle Swarm Optimization (PSO) algorithm to solve the optimal network reconfiguration problem for power loss reduction. The PSO is a relatively new and powerful intelligence evolution method for solving optimization problems. It is a population-based approach. The PSO was inspired from natural behavior of the bees on how they find the location of most flowers. The proposed PSO algorithm is introduced with some modifications such as using an inertia weight that decreases linearly during the simulation. This setting allows the PSO to explore a large area at the start of the simulation.
Volume ray casting algorithms benefit greatly with recent increase of GPU capabilities and power. In this paper,
we present a novel memory efficient ray casting algorithm for unstructured grids completely implemented on GPU
using a recent off-the-shelf nVidia graphics card. Our approach is built upon a recent CPU ray casting algorithm,
called VF-Ray, that considerably reduces the memory footprint while keeping good performance. In addition to
the implementation of VF-Ray in the graphics hardware, we also propose a restructuring in its data structures. As
a result, our algorithm is much faster than the original software version, while using significantly less memory, it
needed only one-half of its previous memory usage. Comparing our GPU implementation to other hardware-based
ray casting algorithms, our approach used between three to ten times less memory. These results made it possible
for our GPU implementation to handle larger datasets on GPU than previous approaches.
The promise of computer aided manufacturing is to make materializable structures that could not be fabricated using traditional methods. An example is 3D printed lattices, where variation in the lattice geometry and print media can define a vast spectrum of resulting material behaviour, ranging from fully flexible forms to completely stiff examples with high strength. While these “architected materials” offer huge promise for industrial applications, in practice they are difficult to generate and explore digitally, and even harder to simulate for mechanical testing. In this talk I will outline a range of approaches to the study of architected materials using machine learning. I will describe several projects using graph neural networks (GNNs) to model lattice geometry, and report on a few recent works that construct inverse models. These approaches are progress toward better methods for approximation of the material behaviour of the space of all lattice geometries, offering potential for real-time material feedback at the design stage, and a streamlined selection process for architected materials.
Land Cover Feature Extraction using Hybrid Swarm Intelligence Techniques - A ...IDES Editor
The findings of recent studies are showing strong
evidence to the fact that some aspects of biogeography can be
applied to solve specific problems in science and engineering.
The proposed work presents a hybrid biologically inspired
technique that can be adapted according to the database of
expert knowledge for a more focused satellite image
classification. The paper also presents a comparative study of
our hybrid intelligent classifier with the other recent Soft
Computing Classifiers such as ACO, Hybrid Particle Swarm
Optimization-cAntMiner (PSO-ACO2), Fuzzy sets, Rough-
Fuzzy Tie up and the Semantic Web Based Classifiers and
the traditional probabilistic classifiers such as the Minimum
Distance to Mean Classifier (MDMC) and the Maximum
Likelihood Classifier (MLC).
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Looking for professional printing services in Jaipur? Navpack n Print offers high-quality and affordable stationery printing for all your business needs. Stand out with custom stationery designs and fast turnaround times. Contact us today for a quote!
Transforming an Existing Distribution Network Into Autonomous MICRO-GRID usin...IJERA Editor
A distribution network with renewable and fossil-based resources can be operated as a micro-grid, in autonomous or nonautonomous modes. Autonomous operation of a distribution network requires cautious planning. In this context, a detailed methodology to develop a sustainable autonomous micro-grid is presented in this paper. The proposed methodology suggests novel sizing and siting strategies for distributed generators and structural modifications for autonomous micro-grids. This paper introduces the Particle Swarm Optimization (PSO) algorithm to solve the optimal network reconfiguration problem for power loss reduction. The PSO is a relatively new and powerful intelligence evolution method for solving optimization problems. It is a population-based approach. The PSO was inspired from natural behavior of the bees on how they find the location of most flowers. The proposed PSO algorithm is introduced with some modifications such as using an inertia weight that decreases linearly during the simulation. This setting allows the PSO to explore a large area at the start of the simulation.
Volume ray casting algorithms benefit greatly with recent increase of GPU capabilities and power. In this paper,
we present a novel memory efficient ray casting algorithm for unstructured grids completely implemented on GPU
using a recent off-the-shelf nVidia graphics card. Our approach is built upon a recent CPU ray casting algorithm,
called VF-Ray, that considerably reduces the memory footprint while keeping good performance. In addition to
the implementation of VF-Ray in the graphics hardware, we also propose a restructuring in its data structures. As
a result, our algorithm is much faster than the original software version, while using significantly less memory, it
needed only one-half of its previous memory usage. Comparing our GPU implementation to other hardware-based
ray casting algorithms, our approach used between three to ten times less memory. These results made it possible
for our GPU implementation to handle larger datasets on GPU than previous approaches.
The promise of computer aided manufacturing is to make materializable structures that could not be fabricated using traditional methods. An example is 3D printed lattices, where variation in the lattice geometry and print media can define a vast spectrum of resulting material behaviour, ranging from fully flexible forms to completely stiff examples with high strength. While these “architected materials” offer huge promise for industrial applications, in practice they are difficult to generate and explore digitally, and even harder to simulate for mechanical testing. In this talk I will outline a range of approaches to the study of architected materials using machine learning. I will describe several projects using graph neural networks (GNNs) to model lattice geometry, and report on a few recent works that construct inverse models. These approaches are progress toward better methods for approximation of the material behaviour of the space of all lattice geometries, offering potential for real-time material feedback at the design stage, and a streamlined selection process for architected materials.
Land Cover Feature Extraction using Hybrid Swarm Intelligence Techniques - A ...IDES Editor
The findings of recent studies are showing strong
evidence to the fact that some aspects of biogeography can be
applied to solve specific problems in science and engineering.
The proposed work presents a hybrid biologically inspired
technique that can be adapted according to the database of
expert knowledge for a more focused satellite image
classification. The paper also presents a comparative study of
our hybrid intelligent classifier with the other recent Soft
Computing Classifiers such as ACO, Hybrid Particle Swarm
Optimization-cAntMiner (PSO-ACO2), Fuzzy sets, Rough-
Fuzzy Tie up and the Semantic Web Based Classifiers and
the traditional probabilistic classifiers such as the Minimum
Distance to Mean Classifier (MDMC) and the Maximum
Likelihood Classifier (MLC).
Affordable Stationery Printing Services in Jaipur | Navpack n PrintNavpack & Print
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VAT Registration Outlined In UAE: Benefits and Requirementsuae taxgpt
Vat Registration is a legal obligation for businesses meeting the threshold requirement, helping companies avoid fines and ramifications. Contact now!
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What is the TDS Return Filing Due Date for FY 2024-25.pdfseoforlegalpillers
It is crucial for the taxpayers to understand about the TDS Return Filing Due Date, so that they can fulfill your TDS obligations efficiently. Taxpayers can avoid penalties by sticking to the deadlines and by accurate filing of TDS. Timely filing of TDS will make sure about the availability of tax credits. You can also seek the professional guidance of experts like Legal Pillers for timely filing of the TDS Return.
What are the main advantages of using HR recruiter services.pdfHumanResourceDimensi1
HR recruiter services offer top talents to companies according to their specific needs. They handle all recruitment tasks from job posting to onboarding and help companies concentrate on their business growth. With their expertise and years of experience, they streamline the hiring process and save time and resources for the company.
Memorandum Of Association Constitution of Company.pptseri bangash
www.seribangash.com
A Memorandum of Association (MOA) is a legal document that outlines the fundamental principles and objectives upon which a company operates. It serves as the company's charter or constitution and defines the scope of its activities. Here's a detailed note on the MOA:
Contents of Memorandum of Association:
Name Clause: This clause states the name of the company, which should end with words like "Limited" or "Ltd." for a public limited company and "Private Limited" or "Pvt. Ltd." for a private limited company.
https://seribangash.com/article-of-association-is-legal-doc-of-company/
Registered Office Clause: It specifies the location where the company's registered office is situated. This office is where all official communications and notices are sent.
Objective Clause: This clause delineates the main objectives for which the company is formed. It's important to define these objectives clearly, as the company cannot undertake activities beyond those mentioned in this clause.
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Liability Clause: It outlines the extent of liability of the company's members. In the case of companies limited by shares, the liability of members is limited to the amount unpaid on their shares. For companies limited by guarantee, members' liability is limited to the amount they undertake to contribute if the company is wound up.
https://seribangash.com/promotors-is-person-conceived-formation-company/
Capital Clause: This clause specifies the authorized capital of the company, i.e., the maximum amount of share capital the company is authorized to issue. It also mentions the division of this capital into shares and their respective nominal value.
Association Clause: It simply states that the subscribers wish to form a company and agree to become members of it, in accordance with the terms of the MOA.
Importance of Memorandum of Association:
Legal Requirement: The MOA is a legal requirement for the formation of a company. It must be filed with the Registrar of Companies during the incorporation process.
Constitutional Document: It serves as the company's constitutional document, defining its scope, powers, and limitations.
Protection of Members: It protects the interests of the company's members by clearly defining the objectives and limiting their liability.
External Communication: It provides clarity to external parties, such as investors, creditors, and regulatory authorities, regarding the company's objectives and powers.
https://seribangash.com/difference-public-and-private-company-law/
Binding Authority: The company and its members are bound by the provisions of the MOA. Any action taken beyond its scope may be considered ultra vires (beyond the powers) of the company and therefore void.
Amendment of MOA:
While the MOA lays down the company's fundamental principles, it is not entirely immutable. It can be amended, but only under specific circumstances and in compliance with legal procedures. Amendments typically require shareholder
The world of search engine optimization (SEO) is buzzing with discussions after Google confirmed that around 2,500 leaked internal documents related to its Search feature are indeed authentic. The revelation has sparked significant concerns within the SEO community. The leaked documents were initially reported by SEO experts Rand Fishkin and Mike King, igniting widespread analysis and discourse. For More Info:- https://news.arihantwebtech.com/search-disrupted-googles-leaked-documents-rock-the-seo-world/
Digital Transformation and IT Strategy Toolkit and TemplatesAurelien Domont, MBA
This Digital Transformation and IT Strategy Toolkit was created by ex-McKinsey, Deloitte and BCG Management Consultants, after more than 5,000 hours of work. It is considered the world's best & most comprehensive Digital Transformation and IT Strategy Toolkit. It includes all the Frameworks, Best Practices & Templates required to successfully undertake the Digital Transformation of your organization and define a robust IT Strategy.
Editable Toolkit to help you reuse our content: 700 Powerpoint slides | 35 Excel sheets | 84 minutes of Video training
This PowerPoint presentation is only a small preview of our Toolkits. For more details, visit www.domontconsulting.com
Enterprise Excellence is Inclusive Excellence.pdfKaiNexus
Enterprise excellence and inclusive excellence are closely linked, and real-world challenges have shown that both are essential to the success of any organization. To achieve enterprise excellence, organizations must focus on improving their operations and processes while creating an inclusive environment that engages everyone. In this interactive session, the facilitator will highlight commonly established business practices and how they limit our ability to engage everyone every day. More importantly, though, participants will likely gain increased awareness of what we can do differently to maximize enterprise excellence through deliberate inclusion.
What is Enterprise Excellence?
Enterprise Excellence is a holistic approach that's aimed at achieving world-class performance across all aspects of the organization.
What might I learn?
A way to engage all in creating Inclusive Excellence. Lessons from the US military and their parallels to the story of Harry Potter. How belt systems and CI teams can destroy inclusive practices. How leadership language invites people to the party. There are three things leaders can do to engage everyone every day: maximizing psychological safety to create environments where folks learn, contribute, and challenge the status quo.
Who might benefit? Anyone and everyone leading folks from the shop floor to top floor.
Dr. William Harvey is a seasoned Operations Leader with extensive experience in chemical processing, manufacturing, and operations management. At Michelman, he currently oversees multiple sites, leading teams in strategic planning and coaching/practicing continuous improvement. William is set to start his eighth year of teaching at the University of Cincinnati where he teaches marketing, finance, and management. William holds various certifications in change management, quality, leadership, operational excellence, team building, and DiSC, among others.
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Attending a job Interview for B1 and B2 Englsih learnersErika906060
It is a sample of an interview for a business english class for pre-intermediate and intermediate english students with emphasis on the speking ability.
Implicitly or explicitly all competing businesses employ a strategy to select a mix
of marketing resources. Formulating such competitive strategies fundamentally
involves recognizing relationships between elements of the marketing mix (e.g.,
price and product quality), as well as assessing competitive and market conditions
(i.e., industry structure in the language of economics).
Putting the SPARK into Virtual Training.pptxCynthia Clay
This 60-minute webinar, sponsored by Adobe, was delivered for the Training Mag Network. It explored the five elements of SPARK: Storytelling, Purpose, Action, Relationships, and Kudos. Knowing how to tell a well-structured story is key to building long-term memory. Stating a clear purpose that doesn't take away from the discovery learning process is critical. Ensuring that people move from theory to practical application is imperative. Creating strong social learning is the key to commitment and engagement. Validating and affirming participants' comments is the way to create a positive learning environment.
[Note: This is a partial preview. To download this presentation, visit:
https://www.oeconsulting.com.sg/training-presentations]
Sustainability has become an increasingly critical topic as the world recognizes the need to protect our planet and its resources for future generations. Sustainability means meeting our current needs without compromising the ability of future generations to meet theirs. It involves long-term planning and consideration of the consequences of our actions. The goal is to create strategies that ensure the long-term viability of People, Planet, and Profit.
Leading companies such as Nike, Toyota, and Siemens are prioritizing sustainable innovation in their business models, setting an example for others to follow. In this Sustainability training presentation, you will learn key concepts, principles, and practices of sustainability applicable across industries. This training aims to create awareness and educate employees, senior executives, consultants, and other key stakeholders, including investors, policymakers, and supply chain partners, on the importance and implementation of sustainability.
LEARNING OBJECTIVES
1. Develop a comprehensive understanding of the fundamental principles and concepts that form the foundation of sustainability within corporate environments.
2. Explore the sustainability implementation model, focusing on effective measures and reporting strategies to track and communicate sustainability efforts.
3. Identify and define best practices and critical success factors essential for achieving sustainability goals within organizations.
CONTENTS
1. Introduction and Key Concepts of Sustainability
2. Principles and Practices of Sustainability
3. Measures and Reporting in Sustainability
4. Sustainability Implementation & Best Practices
To download the complete presentation, visit: https://www.oeconsulting.com.sg/training-presentations
LA HUG - Video Testimonials with Chynna Morgan - June 2024Lital Barkan
Have you ever heard that user-generated content or video testimonials can take your brand to the next level? We will explore how you can effectively use video testimonials to leverage and boost your sales, content strategy, and increase your CRM data.🤯
We will dig deeper into:
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2. How to leverage your testimonials to boost your sales 💲
3. How you can capture more CRM data to understand your audience better through video testimonials. 📊
"𝑩𝑬𝑮𝑼𝑵 𝑾𝑰𝑻𝑯 𝑻𝑱 𝑰𝑺 𝑯𝑨𝑳𝑭 𝑫𝑶𝑵𝑬"
𝐓𝐉 𝐂𝐨𝐦𝐬 (𝐓𝐉 𝐂𝐨𝐦𝐦𝐮𝐧𝐢𝐜𝐚𝐭𝐢𝐨𝐧𝐬) is a professional event agency that includes experts in the event-organizing market in Vietnam, Korea, and ASEAN countries. We provide unlimited types of events from Music concerts, Fan meetings, and Culture festivals to Corporate events, Internal company events, Golf tournaments, MICE events, and Exhibitions.
𝐓𝐉 𝐂𝐨𝐦𝐬 provides unlimited package services including such as Event organizing, Event planning, Event production, Manpower, PR marketing, Design 2D/3D, VIP protocols, Interpreter agency, etc.
Sports events - Golf competitions/billiards competitions/company sports events: dynamic and challenging
⭐ 𝐅𝐞𝐚𝐭𝐮𝐫𝐞𝐝 𝐩𝐫𝐨𝐣𝐞𝐜𝐭𝐬:
➢ 2024 BAEKHYUN [Lonsdaleite] IN HO CHI MINH
➢ SUPER JUNIOR-L.S.S. THE SHOW : Th3ee Guys in HO CHI MINH
➢FreenBecky 1st Fan Meeting in Vietnam
➢CHILDREN ART EXHIBITION 2024: BEYOND BARRIERS
➢ WOW K-Music Festival 2023
➢ Winner [CROSS] Tour in HCM
➢ Super Show 9 in HCM with Super Junior
➢ HCMC - Gyeongsangbuk-do Culture and Tourism Festival
➢ Korean Vietnam Partnership - Fair with LG
➢ Korean President visits Samsung Electronics R&D Center
➢ Vietnam Food Expo with Lotte Wellfood
"𝐄𝐯𝐞𝐫𝐲 𝐞𝐯𝐞𝐧𝐭 𝐢𝐬 𝐚 𝐬𝐭𝐨𝐫𝐲, 𝐚 𝐬𝐩𝐞𝐜𝐢𝐚𝐥 𝐣𝐨𝐮𝐫𝐧𝐞𝐲. 𝐖𝐞 𝐚𝐥𝐰𝐚𝐲𝐬 𝐛𝐞𝐥𝐢𝐞𝐯𝐞 𝐭𝐡𝐚𝐭 𝐬𝐡𝐨𝐫𝐭𝐥𝐲 𝐲𝐨𝐮 𝐰𝐢𝐥𝐥 𝐛𝐞 𝐚 𝐩𝐚𝐫𝐭 𝐨𝐟 𝐨𝐮𝐫 𝐬𝐭𝐨𝐫𝐢𝐞𝐬."
2. Folding
in
Nature:
Protein
Folding
from
random
coil
(wikipedia)
Extreme
Mechanics
Geological
fold
in
Poland.
Manufacturing
:
Microrobo,cs
Lab
Whiteside
Lab
What
Drives
Blooming,
or
Leaves
shape
?
Liang
and
Mahadevan.
Growth,
geometry,
and
mechanics
of
a
blooming
lily.
ONAS
2011
Incorporate
foldable
structure
with
electronics
Biological
Tissues
:
Gut,
intes,ne,
brain
folds
Adv.
Funct.
Mater.
2010,
20,
28–35
Savin
et
al.
On
the
growth
and
form
of
the
gut.
PNAS
2011
3. lgorithms of resolution of the individual elements (tiles) and the number of
gning the elements that can be effectively combined in a single sheet. First,
an object the resolution of the tiles is limited by the scalability of each
he stickers element. The current materials and methods use to create the
substrate can be reasonably shrunk to create tiles on the order
Folding
in
Manufacturing
and
Engineering
of a few millimeters in largest dimension. Below this threshold,
lithography and micromolding techniques (for example, molding
described elastomers using capillary action (25)) could be used to reduce
ty-two-tile feature sizes further. Scaling of actuation has two considerations:
Folding
in
Engineering
:
Foldable
Robo,cs
Foldable
Solar
Cells
Foldable
BaZeries
Paper
Based
Electronics
…..
own in lower right—mm:ss.s) of a self-folding “boat.”(A). All actuators receiving current
boat on side (D).
Programmable
Magne,c
Self-‐assembly
Hawkes et al.
PNAS
∣
July
13,
2010
∣
vol.
107
∣
no.
28
∣
Appl. Phys. Lett. 96, 071902 ͑2010͒
071902-2 Myers, Bernardi, and Grossman Appl. Phys. Lett. 96, 071902 ͑2010͒
hematics of 3DPV structures: ͑a͒ GA-optimized
Foldable
3DPV
4 triangles inside the bounding box; ͑b͒ funnel, a
GA-optimized structures that retains their supe-
Solar
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Deployment
of
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Cells
FIG. 2. ͑Color online͒ Schematics of 3DPV structures: ͑a͒ GA-optimized
structure shown with all 64 triangles inside the bounding box; ͑b͒ funnel, a
er shapes.
More
than
2/3
of
the
cost
of
PV
systems
is
simplified version of most GA-optimized structures that retains their supe-
rior performance over other shapes.
gredients ofMarch
15,
2005
vol.
102
no.
11
PNAS
the complicated GA struc- in
deployment
cost.
contains most key ingredients of the complicated GA struc-
tures.
e energy generated byppl.
Phys.
LeZ.
96,
071902,
2010
Myers,
et
al.
A simple open-box
We compared the energy generated by simple open-box
l structures through a figure of merit M,
shapes and the funnel structures through a figure of merit M,
4. How
Auxe,cs
(NPR)
Materials
work
news and views
Unstretched Stretched Daedalus
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Figure 1 Positive and negative Poisson’s ratios. Stretching these two-dimensional hexagonal distinguis
structures horizontally reveals the physical origin of Poisson’s ratio. a, The cells of regular side. A pu
Miura-‐ori
fold
honeycomb or hexagonal crystals elongate and narrow when stretched, causing lateral contraction
and so a positive Poisson’s ratio. b, In artificial honeycomb with inverted cells, the structural
launched
or bottom
elements unfold, causing lateral expansion and a negative Poisson’s ratio. simultane
page only,
Proper,es:
so the overall Poisson’s ratio is almost always membranes. The overall elasticity of a cell page was a
positive. membrane results from both the protein A suffi
Absorb
Energy,
resist
fracture.
The elastic behaviour of the membranes skeleton and the high lipid content, but the trace a sin
studied by Bowick et al.1 is said to be ‘uni- relative contributions are not yet known. letters fro
versal’ because the authors require only a Even so, Bowick and colleagues’ results are
Some
applica,ons:
body
armor,
an opaque
sparse set of assumptions to predict the provocative. If our usual expectations about absorb th
Poisson’s ratio. They start with a simple net- how things deform do not apply to biological
shock
absorber,
packing
material,
sharp atte
work of nodes, resembling a fishing net with membranes then we may need to reconsider or ‘echo’ c
,
fixed connections, which they model using the influence of membrane mechanics7 on letter. A b
knew
and
elbow
pads,
sponge
a Monte Carlo simulation. Bowick et al. the shape of cells, the formation of vesicles, the stream
show that a negative Poisson’s ratio is a uni- and the deformation of cells during life photocell
mops.
versal property of such systems, whether the processes. For example, red blood cells are Unfort
membrane is dominated by rigid bonds that routinely deformed when they pass through both sides
resist bending or by ‘self-avoiding’ inter- fine blood capillaries. As they deform, the may be in
silver.neep.wisc.edu/~lakes/Poisson.html
atomic forces that prevent portions of the membrane skeleton can unfold, which both of wh
structure overlapping.
This unusual form of elasticity may also
Metallic
Foam
might help to transport large molecules or
expose reactive chemical groups. Similar
But this is
come in. E
5. Poisson
Ra,o
is
a
very
important
mechanical
REVIEW ARTICLE NATURE MATERIALS DOI: 10.1038/NMAT3134
proper,es
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Lead Rubber
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Metallic glasses
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ty
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i
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dc
ck
pa
e
Carbon nanotube Laminates
as
er
re
sheets
ns
–0.2
Inc
De
α-cristobalite
Unscreened metals Bi, As
–0.4 Laser-cooled crystals
Colloidal crystals
–0.6
Re-entrant polymer foams
–0.8
Critical fluids
–1.0
–1.2
0.001 0.01 0.1 1 10 100
B/G
b
Bulk modulus B c
bulk
modulus
B
BMG hange
in
size
-‐
c
• ν
=
[3(B/G
–
2)]/[6(B/G
+
2)]
400 fcc
Unstable by
domain
Rubbery Stiff
350
shear
modulus
G
–
change
in
shape
Ductile
bcc
ν = 1/2 ν = 0.3 Brittle
ν
=
[1⁄2(Vt/Vl)2
–
1]/[(Vt/Vl)2
–
1]
formation
• 300
B/G = 2.4 hcp
Stable
• isotropic
range
of
–1
≤
ν
≤
1⁄2
for
0
≤
B/G
<
∞
at
small
strains
250
B (GPa)
ν=0 Fe–
450 Ni– Unreachable
• Nonlinear
regime
ν
<
-‐1.
Spongy
Anti-rubbery 200 Pd–
Ideal isotropic solid
Dilational
ν = –1 150 Cu– B/G = 5/3
Auxetic
Foam
Structures
wν2= –2
Nega*ve
Poissson's
Ra*o.
Lakes.
science.
1987.
ν =
ith
a Shear modulus G 100 RE- fcc metals
–4G/3 < B < 0 Zr– bcc metals
Unstable by volume change
ν=1 50 hcp metals
Poisson’s
ra*o
and
modern
materials.
Nature
Materials.
G.
N.
Greaves,
but stable if constrained Mg–
A.
L.
Greer,
R.
S.
Lakes
and
T.
Rouxel
24
Oct
2011
0
0 50 100 150 200 250
6. Project
• Make
Mouri-‐Ori
Fold.
• Vary
angle
to
vary
mechanical
proper,es.
• How
does
the
rela,on
look
like.
• Measure
Poisson
ra,os.
Miura-‐ori
paZern
is
a
Rhomboidal
(2
angles
,
2
lengths).
• They
developed
computa,onal
tool
to
simulate
the
stretching,
bending
and
folding
of
thin
sheets
of
material
to
predict
its
mechanical
proper,es.
Pleated
and
Creased
Structures.
Levi
Dudte,
Zhiyan
Wei,
L.
Mahadevan.
APS
2012
Mee,ng.
2:30
PM–5:30
PM,
Tuesday,
February
28,
2012
Room:
153C
8. Possion
ra,o
measurements
Strain
Vs.
strain
plots
for
SU-‐8
microstructures
to
measure
NPR
(no
varying
of
angles)
~100
μm
Adv.
Mater.
1999,
11,
No.
14
9. Acknowledgment
• Applied
Math
Lab
– Advisor
and
PI:
L.
Mahadevan
–
Levi
Dudte
–
Zhiyan
Wei
• Microrobo,cs
Lab
– PI:
Robert
Woods
– Lab
Manger:
Michael
Smith.
11. Problems
faced
• Project
start
Monday,
Feb
6
2012:
17
days
only
and
talked
to
students
much
later.
• No
sotware
access
(Corel
Draw,
AutoCAD)
• Hard
access
to
Laser
Lab
• Access
to
lab
to
measure
passion
ra,o.