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Bats Use Water Ripples to Hunt Frogs

By Guest PostJanuary 26, 2014Nature, Scienceanti predator strategy, austin, bats, central, echolocation, eeb, frog, frog eating bats, leiden university, male tungara frog, mike ryan, natural form, physalaemus pustulosus, predator, pulsating sac, rachel page, rival, ryan taylor, salisbury university, sonar, south america, stri, trachops cirrhosus, university of texas, water ripples, wouter halfwerk

AUSTIN, Texas — As the male túngara frog serenades female frogs from a pond, he creates watery ripples that make him easier to target by rivals and predators such as bats, according to researchers from The University of Texas at Austin, the Smithsonian Tropical Research Institute (STRI), Leiden University and Salisbury University.

A túngara frog will stop calling if it sees a bat overhead, but ripples continue moving for several seconds after the call ceases. In the study, published this week in the journal Science, researchers found evidence that bats use echolocation — a natural form of sonar — to detect these ripples and home in on a frog. The discovery sheds light on an ongoing evolutionary arms race between frogs and bats. (more…)

Mutations in Genes that Modify DNA Packaging Result in form of Muscular Dystrophy

By Guest PostNovember 22, 2012Sciencebiopsies, chromatin structure, chromosome 4, culture, daniel g miller, devastating disease, dna sequence, facioscapulohumeral muscular dystrophy, family history, fshd, genetic deletions, genetic disorder, genetic material, genome, leiden university, medical geneticists, michael bamshad, muscle cell, muscle toxic dux4, mutation, protein, rabi tawil, rochester, silvere, smchd1 gene, stephen tapscott, symptom, the netherlands, university, van der maarel, Washington

A recent finding by medical geneticists sheds new light on how facioscapulohumeral muscular dystrophy develops and how it might be treated. More commonly known as FSHD, the devastating disease affects both men and women.

FSHD is usually an inherited genetic disorder, yet sometimes appears spontaneously via new mutations in individuals with no family history of the condition.

“People with the condition experience progressive muscle weakness and about 1 in 5 require wheelchair assistance by age 40,” said Dr. Daniel G. Miller, University of Washington associate professor of pediatrics in the Division of Genetic Medicine. Miller and his worldwide collaborators study the molecular events leading to symptoms of FSHD in the hopes of designing therapies to prevent the emergence of symptoms or reduce their severity. (more…)

W3C Announces First Draft of Standard for Online Privacy

By Guest PostNovember 17, 2011Technologyadobe systems, advertisers, alcatel lucent, aleecia m mcdonald, apple inc, bluecava, browser vendors, content providers, deutsche telekom ag, do not track, Facebook, individual privacy, leiden university, matthias schunter, mozilla foundation, print media, privacy on the web, search engines, social networking widgets, tracking protection working group, tv commercials, w3c, web business models, web site owners

*Do Not Track Approach Balances User Preferences with Personalized Web Experiences*

CAMBRIDGE, Mass. – 17 Nov 2011: To address rising concerns about privacy on the Web, W3C has published two first drafts for standards that allow users to express preferences about online tracking:

Tracking Preference Expression (DNT), which defines mechanisms for users to express cross-site tracking preferences and for sites to indicate whether they honor these preferences.
Tracking Compliance and Scope, which defines the meaning of a “Do Not Track” preference and sets out practices for websites to comply with this preference.

These documents are the early work of a broad set of stakeholders in the W3C Tracking Protection Working Group, including browser vendors, content providers, advertisers, search engines, and experts in policy, privacy, and consumer protection. W3C invites review of these early drafts, which are starting points of work to come. W3C expects them to become standards by mid-2012. (more…)

Astronomer Tom Gehrels, 1925-2011

By Guest PostJuly 14, 2011Scienceasteroids and comets, astronomer, astronomy, Britain, Chicago, dutch resistance, earth, England, gerard p kuiper, haarlemmermeer, harold masursky award, imaging photopolarimetry, jupiter, kitt peak, leiden university, nobel astrophysicist, saturn, saturn mysterious f ring, special operations executive, study of wavelength dependence of polarization of stars and planets, subrahmanyan chandrasekhar, the netherlands, tom gehrels, universal evolution, university of arizona, university of chicago

*In a career that spanned more than half a century, Gehrels fostered new research on asteroids and comets, including those that pose a threat to Earth.*

Tom Gehrels, an internationally noted planetary scientist and astronomer at the University of Arizona, as well as a hero of the Dutch Resistance during WWII, died Monday. He was 86.

Gehrels was among the first members of the fledgling Lunar and Planetary Laboratory when he joined the UA in 1961. During a long and distinguished career Gehrels pioneered new research on asteroids and comets, especially those that pose a collision threat to Earth. He also developed and taught introductory astronomy courses that were popular with non-science undergraduates. (more…)

Tag Archives: leiden university

Bats Use Water Ripples to Hunt Frogs

Mutations in Genes that Modify DNA Packaging Result in form of Muscular Dystrophy

W3C Announces First Draft of Standard for Online Privacy

Astronomer Tom Gehrels, 1925-2011