Navigation Links
True grit
Date:5/4/2009

Sea urchins dig themselves hiding holes in the limestone of the ocean floor using teeth that don't go blunt. Weizmann Institute scientists have now revealed their secrets, which might give engineers insights into creating ever-sharp tools or mechanical parts.

The urchins dig holes to fit their globular bodies using their five teeth, which, like those of rodents, are ground down at the tip but continue to grow on the other end throughout the animals' lives. The amazing part, however, is that the teeth, which need to be harder and stronger than the rocky limestone being dug out, are themselves made almost entirely of calcite the same calcite that makes up much of the limestone. How is this possible? In a series of studies spanning more than a decade, Profs. Steve Weiner and Lia Addadi of Weizmann's Structural Biology Department have discovered that the urchins' secret lies in a combination of ingenious design strategies. The latest of these studies, conduc ted with postdoctoral fellow Yurong Ma and graduate student Yael Politi and in collaboration with Prof. Pupa Gilbert and Dr. Rebecca Metzler of the University of Wisconsin, Drs. Barbara Aichmayer, Oskar Paris and Peter Fratzl from the Max Planck Institute of Colloids and Interfaces in Potsdam, Germany, and Dr. Anders Meibom from Museum National D'Histoire Naturelle in Paris, France, was reported recently in the Proceedings of the National Academy of Sciences (PNAS), USA.

The scientists found that the sea urchins' teeth contain crystals of magnesium calcite, which are smaller, harder and denser than those of pure calcite; they are concentrated at the grinding tip of the tooth, particularly in the tip's center, where the most force is being exerted in the course of grinding. What holds these crystals at the center of the tip is a matrix of larger and softer calcite crystals. While in most such materials a matrix of hard fibers contains a softer filling, the reverse is true for the urchin
'/>"/>

Contact: Yivsam Azgad
news@weizmann.ac.il
972-893-43856
Weizmann Institute of Science
Source:Eurekalert

Page: 1 2

Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/24/2015)... BEACH GARDENS, Fla. , March 24, 2015 ... biometric identity management solutions, today announced that its ... premium clothing accessory retailer Goorin Bros . ... The Crossmatch biometrics-based solution secures access to the ... from the increased risk of data breaches. ...
(Date:3/23/2015)... OXFORD, Conn. , Mar. 23, 2015 NXT-ID, Inc. ... authentication company focused on the growing mobile commerce market, announces ... a new advertising campaign on CNBC television starting March 30 ... ads will commence airing in New York ... Executive Officer said: "We are excited about our new ad ...
(Date:3/20/2015)... 2015 Research and Markets ( http://www.researchandmarkets.com/research/vkzvcs/iris_biometrics ) ... Global Strategic Business Report" report to their offering. ... in US$ Thousands. The report provides separate comprehensive analytics for ... , Europe , Asia-Pacific ... Latin America . Annual estimates and ...
Breaking Biology News(10 mins):Crossmatch Fingerprint Readers Help Retailer Prevent Data Breaches at Point-of-Sale 2NXT-ID's Wocket Smart Wallet to Launch New CNBC Regional TV Ad Campaign 2NXT-ID's Wocket Smart Wallet to Launch New CNBC Regional TV Ad Campaign 3Iris Biometrics - Global Strategic Business Report 2015: System & Network Access Control - A Robust Market Opportunity in the Offing 2Iris Biometrics - Global Strategic Business Report 2015: System & Network Access Control - A Robust Market Opportunity in the Offing 3Iris Biometrics - Global Strategic Business Report 2015: System & Network Access Control - A Robust Market Opportunity in the Offing 4Iris Biometrics - Global Strategic Business Report 2015: System & Network Access Control - A Robust Market Opportunity in the Offing 5
... February 1, 2011. Fact: The sex of some species ... warm nests produce females, cooler nests, males. And although ... years, scientists now report that almost half of the turtle ... global warming may affect turtle reproduction. To bring attention to ...
... species present a serious environmental, economic and social problem ... biodiversity and ecosystem functions, such as nutrient cycling. Despite ... can dominate new habitats over native plants that technically ... tested assumption is that these plants are more abundant ...
... key to preventing deaths from measles. Despite the availability ... children worldwide, particularly in less-developed regions where vaccination coverage ... at the Johns Hopkins Bloomberg School of Public Health ... a dry powder, live-attenuated measles vaccine that can be ...
Cached Biology News:Turtle populations affected by climate, habitat loss and overexploitation 2Home and away: How do invasive plant species dominate native species? 2Researchers test inhalable measles vaccine 2
(Date:4/24/2015)... Texas (PRWEB) April 24, 2015 ... for use in applications such as animal waste ... and oil reduction in wastewater treatment plants and ... an exhibitor at the National Restaurant Association’s NRA ... , Representatives of the company will be ...
(Date:4/24/2015)... 2015 PAREXEL International Corporation (NASDAQ: ... announced that Partnerships in Clinical Trials named PAREXEL,s ... Clinical Innovator of the Year.  The honor recognizes Mr. ... Company,s Perceptive MyTrials ® Data-Driven Monitoring solution. ... the 2015 Partnership Awards in Boston ...
(Date:4/23/2015)... 23, 2015 /CNW/ - A new and innovative service ... North America,s largest packaging ... Silver in the "Sustainability, service" category of the ... "Competitor Comparison" is a service that scores clients, ... Global peers. This benchmarking process shows clients how ...
(Date:4/23/2015)... April 23, 2015 Follow ... to a series of genetic tests that determine ... Lou Gehrig's disease, Huntington's disease, and Alzheimer's disease. ... gene composition and interaction in diseased tissue/cells to ... well as the response to treatment, such as ...
Breaking Biology Technology:DryLet to Showcase Bio-React at the National Restaurant Association’s NRA Show 2015 May 16-19, 2015 in Chicago, Illinois 2PAREXEL Honored With 2015 Clinical Innovator Of The Year Award From Partnerships In Clinical Trials 2PAREXEL Honored With 2015 Clinical Innovator Of The Year Award From Partnerships In Clinical Trials 3PAREXEL Honored With 2015 Clinical Innovator Of The Year Award From Partnerships In Clinical Trials 4PAREXEL Honored With 2015 Clinical Innovator Of The Year Award From Partnerships In Clinical Trials 5Increasing Disease Prevalence & Focus on Preventive Healthcare Drive the Predictive Diagnostics Market, According to a New Report by Global Industry Analysts, Inc. 2Increasing Disease Prevalence & Focus on Preventive Healthcare Drive the Predictive Diagnostics Market, According to a New Report by Global Industry Analysts, Inc. 3
... , ... • LEADseeker • DeepBlueC• cell-based assays , ... Competitive pressure is forcing organizations to continually increase screening ... screens such as luminescence cell-based assays. LEADseeker™ Multimodality Imaging System was ...
... , Key ... amplification (WGA),• degenerate oligonucleotideprimed PCR (DOP-PCR),• Cy3/Cy5-dCTP probe labeling ... array • array CGH ... Human genomic DNA isolated from formalin-fixed ...
... Amounts of Data into Gems of Knowledge Using discoveryHub™ ... Abstract , This paper discusses key problems and ... (volume) and complexity of life science data available today, ... integration that enables rapid ‘harvesting’ and analysis of critical ...
Cached Biology Technology:Use of BRET2 luminescence cell-based assays with LEADseeker Multimodality Imaging System 2Use of BRET2 luminescence cell-based assays with LEADseeker Multimodality Imaging System 3GenomiPhi amplification of FFPE tissue DNA for array CGH 2GenomiPhi amplification of FFPE tissue DNA for array CGH 3GenomiPhi amplification of FFPE tissue DNA for array CGH 4GenomiPhi amplification of FFPE tissue DNA for array CGH 5GenomiPhi amplification of FFPE tissue DNA for array CGH 6GenomiPhi amplification of FFPE tissue DNA for array CGH 7GenomiPhi amplification of FFPE tissue DNA for array CGH 8GenomiPhi amplification of FFPE tissue DNA for array CGH 9GenomiPhi amplification of FFPE tissue DNA for array CGH 10Exploiting the Life Science Data Explosion to Speed New Drug Discovery 2Exploiting the Life Science Data Explosion to Speed New Drug Discovery 3Exploiting the Life Science Data Explosion to Speed New Drug Discovery 4Exploiting the Life Science Data Explosion to Speed New Drug Discovery 5Exploiting the Life Science Data Explosion to Speed New Drug Discovery 6Exploiting the Life Science Data Explosion to Speed New Drug Discovery 7Exploiting the Life Science Data Explosion to Speed New Drug Discovery 8Exploiting the Life Science Data Explosion to Speed New Drug Discovery 9Exploiting the Life Science Data Explosion to Speed New Drug Discovery 10Exploiting the Life Science Data Explosion to Speed New Drug Discovery 11Exploiting the Life Science Data Explosion to Speed New Drug Discovery 12Exploiting the Life Science Data Explosion to Speed New Drug Discovery 13Exploiting the Life Science Data Explosion to Speed New Drug Discovery 14Exploiting the Life Science Data Explosion to Speed New Drug Discovery 15Exploiting the Life Science Data Explosion to Speed New Drug Discovery 16Exploiting the Life Science Data Explosion to Speed New Drug Discovery 17
... Spike-In Kit contains in vitro synthesized, polyadenylated ... control probes on Agilents microarrays, with minimal ... a positive microarray control in the hybridization ... is a required component of the Agilent ...
... ProtoArray high-density functional protein microarray is the ... of proteinprotein interactions on a proteome scale. ... open reading frames (ORFs) expressed as 5'-GST ... a 1 inch x 3 inch nitrocellulose-coated ...
... of cells • Blade design minimizes cell ... growth surface • Designed for use in ... • Sterilized by gamma radiation and certified ... new product number, created to easily match ...
... Designed for use with dishes and cell ... a new product number, created to easily ... availability yet, please order under the old ... for assistance. Comp Dim: blade L 1.9 ...
Biology Products: