শুক্রবার, ২৯ মার্চ, ২০১৩

Mate choice in mice is heavily influenced by paternal cues, mouse study shows

Mar. 28, 2013 ? Hybrid offspring of different house mice populations show a preference for mating with individuals from their father's original population.

Mate choice is a key factor in the evolution of new animal species. The choice of a specific mate can decisively influence the evolutionary development of a species. In mice, the attractiveness of a potential mate is conveyed by scent cues and ultrasonic vocalizations. Researchers from the Max Planck Institute for Evolutionary Biology in Pl?n investigated whether house mice (Mus musculus) would mate with each other even if they were from two populations which had been separated from each other for a long time period. To do this, the researchers brought together mice from a German population and mice from a French population. Although to begin with all the mice mated with one another randomly, the hybrid offspring of French and German parents were distinctly more choosy: they showed a definite preference for mating with individuals from their father's original population. According to the researchers, this paternal imprinting accelerates the divergence of two house mouse populations and thus promotes speciation.

In allopatric speciation, individuals of a species become geographically isolated from each other by external factors such as mountains or estuaries. Over time, this geographic separation leads to the sub-populations undergoing various mutations, and thus diverging genetically. Animals from the two different sub-populations can no longer successfully reproduce, so two new species evolve.

To find out what role partner selection plays in such speciation processes, Diethard Tautz from the Max Planck Institutefor Evolutionary Biology and his colleagues conducted a comprehensive study on house mice -- the classic model organisms of biology. "To investigate whether there are differences in the mating behaviour of the mice in the early stages of speciation, we caught wild house mice in southern France and western Germany. The two populations have been geographically separate for around 3,000 years, which equates to some 18,000 generations," says Diethard Tautz. Due to this geographical separation, the French and German mice were genetically different.

The Pl?n-based researchers created a semi-natural environment for their investigations -- a sort of "Playboy Mansion" for mice. The research enclosure was several square meters in size and was divided up using wooden walls, "nests" made out of plastic cylinders, and plastic tubes. It also featured an escape tube with several entrances, which led into a cage system nearby. "We constructed the enclosure in such a way that all animals had unimpeded access to all areas, but thanks to the structural divisions were also able to create their own territories or retreat into nests," explains Tautz. "The escape tube was a control element. If the mice retreated to it only very seldom -- as was the case in our experiment -- then we could be sure there was no overpopulation in the central enclosure."

In this central enclosure, the French and German mice had both time and space to mate with each other and reproduce. "At first, all the mice mated with each other quite randomly. But with the first-generation offspring, a surprising pattern emerged," says Tautz. When the first-generation hybrid offspring of mixed French and German parentage mated, they showed a specific preference for pure-bred mates whose "nationality" was that of their father only. "There must be some kind of paternal influence that prompts the hybrid mice to choose a mate from a specific population, namely that of their father," concludes the biologist, based on the results of his study. "This imprinting must be learned, however, meaning that the animals must grow up in the presence of their fathers. This was not the case for the original mice, which were kept in cages for a time after being caught."

"We know that mice use ultrasonic vocalizations to communicate with each other and that particularly in the case of male mice these vocalizations can reveal signals of individuality and kinship. We believe that, like birdsong, the vocalizations of the males have a learned component and a genetic component," says Tautz. Therefore, French and German mice really could "speak" different languages, partly learned from their fathers, partly inherited from them. Individual mice thus have a mating preference for mice that speak the same language as they do.

The French and German mouse populations had evidently been geographically separated long enough for preliminary signs of species differentiation to be apparent as regards mating preferences. In addition, another aspect of mating behavior also sped up the speciation process. Although mice have multiple mates, the researchers found evidence of partner fidelity and inbreeding. The tendency to mate with relatives fosters the creation of genetically uniform groups. When both occur together, this accelerates the speciation process.

In a next step, Diethard Tautz wants to find out whether the vocalizations of the mice play the decisive role in paternal imprinting, or if scent cues are also involved. Furthermore, the biologist wants to identify the genes that are involved in mate selection.

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The above story is reprinted from materials provided by Max-Planck-Gesellschaft.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. Inka Montero, Meike Tesche and Diethard Tautz. Paternal imprinting of mating preferences between natural populations of house mice (Mus musculus domesticus). Molecular Ecology, 2013 DOI: 10.111/mec.122271

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/~3/oUt1DL9X6YE/130328125331.htm

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Amazon reportedly increasing Kindle phone screen size in response to ?phablet? fever

By Brian Homewood March 28 (Reuters) - Swiss champions FC Basel, renowned for their youth development programme, face a constant battle to stop teenage players moving to English, Spanish and Italian clubs. President Bernhard Heusler told Reuters in an interview that parents often do not listen to the club when warned against taking their sons elsewhere. "We get enormous pressure from outside, including English clubs," said Heusler before adding Basel were powerless to stop their youngsters leaving before the age of 16. ...

Source: http://news.yahoo.com/amazon-reportedly-increasing-kindle-phone-screen-size-response-204859764.html

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বৃহস্পতিবার, ২৮ মার্চ, ২০১৩

Kate Gosselin is Now 38 Years Old

Source: http://www.thehollywoodgossip.com/2013/03/kate-gosselin-is-now-38-years-old/

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Exercise helps ease arthritis pain and stiffness | Leisure Fitness ...

Exercise helps ease arthritis pain and stiffness
Article mayoclinic.com, Recommended by Jessica Loeser, Wellness Outreach Team

As you consider starting an arthritis exercise program, understand what?s within your limits and what level of exercise is likely to give you results.

Exercise is crucial for people with arthritis. It increases strength and flexibility, reduces joint pain, and helps combat fatigue. Of course, when stiff and painful joints are already bogging you down, the thought of walking around the block or swimming a few laps might seem overwhelming.

But you don?t need to run a marathon or swim as fast as an Olympic competitor to help reduce the symptoms of your arthritis. Even moderate exercise can ease your pain and help you maintain a healthy weight. When arthritis threatens to immobilize you, exercise keeps you moving. Not convinced? Read on.

Exercise can help you improve your health and fitness without hurting your joints. Along with your current treatment program, exercise can:
-Strengthen the muscles around your joints
-Help you maintain bone strength
-Give you more strength and energy to get through the day
-Make it easier to get a good night?s sleep
-Help you control your weight
-Make you feel better about yourself and improve your sense of well-being

Though you might think exercise will aggravate your joint pain and stiffness, that?s not the case. Lack of exercise actually can make your joints even more painful and stiff. That?s because keeping your muscles and surrounding tissue strong is crucial to maintaining support for your bones. Not exercising weakens those supporting muscles, creating more stress on your joints.

Talk to your doctor about how exercise can fit into your current treatment plan. What types of exercises are best for you depends on your type of arthritis and which joints are involved. Your doctor or a physical therapist can work with you to find the best exercise plan to give you the most benefit with the least aggravation of your joint pain.

Your doctor or physical therapist can recommend exercises that are best for you, which might include range-of-motion exercises, strengthening exercises, aerobic exercise and other activities.

Range-of-motion exercises
These exercises relieve stiffness and increase your ability to move your joints through their full range of motion. Range-of-motion exercises involve moving your joints through their normal range of movement, such as raising your arms over your head or rolling your shoulders forward and backward. These exercises can be done daily or at least every other day.

Strengthening exercises
These exercises help you build strong muscles that help support and protect your joints. Weight training is an example of a strengthening exercise that can help you maintain your current muscle strength or increase it. Do your strengthening exercises every other day ? but take an extra day off if your joints are painful or if you notice any swelling.

Aerobic exercise
Aerobic or endurance exercises help with your overall fitness. They can improve your cardiovascular health, help you control your weight and give you more stamina. That way you?ll have more energy to get through your day. Examples of low-impact aerobic exercises that are easier on your joints include walking, riding a bike and swimming. Try to work your way up to 20 to 30 minutes of aerobic exercise three times a week. You can split up that time into 10-minute blocks if that?s easier on your joints.

Other activities
Any movement, no matter how small, can help. If a particular workout or activity appeals to you, don?t hesitate to ask your doctor whether it?s right for you. Your doctor might give you the OK to try gentle forms of yoga and tai chi. Tai chi may improve balance and help prevent falls. Be sure to tell your instructor about your condition and avoid positions or movements that can cause pain.

Start slowly to ease your joints into exercise if you haven?t been active for a while. If you push yourself too hard, you can overwork your muscles. This can worsen your joint pain.

Apply heat. Heat can relax your joints and muscles and relieve any pain you have before you begin. Heat treatments ? warm towels, hot packs or a shower ? should be warm, not painfully hot, and should be applied for about 20 minutes.

Move gently. Move your joints gently at first to warm up. You might begin with range-of-motion exercises for five to 10 minutes before you move on to strengthening or aerobic exercises.

Go slowly. Exercise with slow and easy movements. If you start noticing pain, take a break. Sharp pain and pain that is stronger than your usual joint pain might indicate something is wrong. Slow down if you notice inflammation or redness in your joints.

Ice afterward. Apply ice to your joints as needed after activity, especially after activity that causes any joint swelling.
Trust your instincts and don?t exert more energy than you think your joints can handle. Take it easy and slowly work your exercise length and intensity up as you progress.

You might notice some pain after you exercise if you haven?t been active for a while. In general, if your pain lasts longer than two hours after you exercise, you were probably exercising too strenuously. Talk to your doctor about what pain is normal and what pain is a sign of something more serious.

If you have rheumatoid arthritis, ask your doctor if you should exercise during general or local flares. One option is to work through your joint flares by doing only range-of-motion exercises, just to keep your body moving.

Check with your doctor about exercise programs in your area for people with arthritis. Hospitals and clinics sometimes offer special programs, as do local health clubs.

The Arthritis Foundation conducts exercise programs for people with arthritis in many parts of the United States. Programs include exercise classes ? in water and on land ? and walking groups. Contact your local branch for more information.

Source: http://blog.leisurefitness.com/2013/03/exercise-helps-ease-arthritis-pain-and-stiffness/

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Egypt: Divers caught while cutting Internet cable

CAIRO (AP) ? Egypt's naval forces captured three scuba divers who were trying to cut an undersea Internet cable in the Mediterranean on Wednesday, a military spokesman said. Telecommunications executives meanwhile blamed a weeklong Internet slowdown on damage caused to another cable by a ship.

Col. Ahmed Mohammed Ali said in a statement on his official Facebook page that divers were arrested while "cutting the undersea cable" of the country's main communications company, Telecom Egypt. The statement said they were caught on a speeding fishing boat just off the port city of Alexandria.

The statement was accompanied by a photo showing three young men, apparently Egyptian, staring up at the camera in what looks like an inflatable launch. It did not further have details on who they were or why they would have wanted to cut a cable.

Egypt's Internet services have been disrupted since March 22. Telecom Egypt executive manager Mohammed el-Nawawi told the private TV network CBC that the damage was caused by a ship, and there would be a full recovery on Thursday.

There was preliminary evidence of slow Internet connections as far away as Pakistan and India, said Jim Cowie, chief technology officer and co-founder of Renesys, a network security firm based in Manchester, N.H., that studies Internet traffic.

A cable cut can cause data to become congested and flow the long way around the world, he said.

It's not the first time cable cuts have affected the Mideast in recent years. Errant ships' anchors are often blamed. Serious undersea cable cuts caused widespread Internet outages and disruptions across the Middle East on two separate occasions in 2008.

Source: http://news.yahoo.com/egypt-divers-caught-while-cutting-internet-cable-213029317.html

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PFT: Lattimore cheered on at Pro Day workout

Divisional Playoffs - Seattle Seahawks v Atlanta FalconsGetty Images

Pittsburgh Steelers head coach Mike Tomlin doesn?t have much faith in the read-zone option being anything more than another passing fad.

Tomlin called the offensive scheme the ?flavor of the month? in the league and feels its success could very much go the way of the Wildcat once defenses have a chance to adjust and figure it out.

?We look forward to stopping it,? Tomlin said. ?We look forward to eliminating it.?

Seattle Seahawks quarterback Russell Wilson is one of a handful of quarterbacks to have been able to incorporate the read-zone concepts and see success. San Francisco?s Colin Kaepernick, Washington?s Robert Griffin III and Carolina?s Cam Newton have also benefited from adding the elements to their offenses.

But Wilson has no intention of just being the ?flavor of the month.? He believes that he, Kaepernick and other quarterbacks that can run are getting unfairly put into a box as ?running quarterbacks? just because they have the ability to run and not being given the credit for their ability to throw the ball or run an offense.

?It doesn?t matter what style of offense, I?m ready to play any time, anywhere, anyplace. I just want to play football. Some people try to take away from our ability to throw the football because we can run. But I think it just adds another dimension to what we do,? Wilson said, via Eric Williams of the?Tacoma News Tribune.

?To be honest with you, people try to take away from the ability that guys have in terms of what Colin Kaepernick and other guys like him can do, for whatever reason, because they?re young, or they?re different,? Wilson added. ?But I think it brings excitement to the game. It brings a challenge to the defense.?

Seattle doesn?t solely rely on the read-zone instead using it only as a complement to their normal offense. Wilson matched Peyton Manning?s record for most touchdown passes by a rookie with 26 last year and had a 20-0 touchdown to interception ratio in the opponent?s red zone. That level of success can?t solely be written off as a byproduct of one offensive scheme alone.

Wilson, Kaepernick and Griffin all proved last season they have the ability to successfully work a passing game in addition to their ability to run when called upon. The thought they will be rendered ineffective by adjustments defenses make to solve the read-zone elements of their offenses seem to be far-fetched.

Source: http://profootballtalk.nbcsports.com/2013/03/27/lattimore-hears-applause-at-pro-day-workout/related/

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Why we write?or don't? | Scholars and Rogues

Erato, Muse of Poetry (Image courtesy Wikimedia)

It?s a bitter day when one sees a talented artist give up his art. Sam Smith?s A Poet Says Goodbye to Poetry reveals a great deal about the state, not just of poetry, but about the state of art ? especially literature.

The State of Things

The divisions between ?high? and ?low? art disappeared more decades ago than most people realize (for the hell of it we might say it happened in the year 1930 ? not because of the economic collapse caused by Wall Street which precipitated the great depression, but because the Pulitzer committee gave the fiction prize that year to Oliver La Farge?s novel Laughing Boy for what were largely political reasons ? the committee?s other options that year were William Faulkner?s The Sound and the Fury, Ernest Hemingway?s A Farewell to Arms, and Thomas Wolfe?s Look Homeward Angel ? any of which choices any educated person might think preferable). The rise of creative writing programs post World War II created, unintentionally, a self-contained world of writers writing for each other ? as a result, educated audiences who might have read Hemingway and Hammett a generation before no longer exist in any appreciable numbers. Those who read Pynchon and Delillo (or even know who Pynchon or Delillo are) are separated from those who read Elmore Leonard or Patricia Cornwell in ways that reflect the economic politics of publishing.

What used to be seen as the ?mid-list responsibility? of once family owned publishing houses like Scribners or Simon and Schuster ? to publish or keep in print (I believe the term used once was ?champion?) literary work, whether fiction or poetry ? is, and has been for some time, over. Shareholders and corporate execs champion profits, not culture. Genre forms ? mystery, horror, fantasy, sci-fi, romance, western ? are reliable sellers ? and some talented writers who might pursue more personal, literary paths have chosen to adapt their artistic visions to genre fiction. Some of these have transcended their genres (Kurt Vonnegut and Cormac McCarthy are examples). But the disappearance of the ?mid-list? gave other, possibly equally talented authors no way to access the marketing muscle of major publishing houses.

As a result talented writers who might have pursued their visions independent of the creative writing school system (which, more than anything else, is like an ?old boy/girl? club where ?mentors? help ?mentees? and the majority of students get shuffled through for their tuition) now turn to small, independent publishers who often find that even getting their authors reviewed ? a staple of arts pages in newspapers only two decades ago but one of the first casualties of the collapse of the newspaper as a medium ? requires them to approach the plethora of ?book bloggers? on the InterWebs whose chief aims seem to be promoting their favorite authors ? and whose overwhelming interests (I looked at nearly 600 book blogs this fall as I helped my publisher pursue reviews for my latest book) are for whatever the current reading fad is (as most of you know, right now it?s something called ?Young Adult Paranormal?). It is a system rife with all the pitfalls and problems of the chaos we know as the Web.

Think for a moment ? what have been the most successful books of the last five years? You know them ? The Twilight, Hunger Games, and Fifty Shades of Grey series. I?ve emphasized that last word for a reason: for the same reasons that movie studios (once taken over by corporate interests) began grinding out sequels for any film with a flicker (however dim) of originality and appeal, mainstream publishers now seek franchises ? they want writers willing to grind out hundreds, even thousands, of pages telling long, convoluted stories (usually rather badly in the opinion of this ?pedantic bastard? as a high school friend once termed me in signing my yearbook) that follow Propp?s Morphology of the Folk Tale the way that kid making your blackened salmon at Applebee?s follows their picture book prep manual to get the ?food? on your plate. The sad part, for this pedantic bastard, is that if I were allowed to approach any of the authors of the above-named series and asked them about Propp, I fear what I?d get would be blank stares followed by calls for their security details to remove me. And what might be worse, to me, would be talking with them and discovering that they were well aware of their use of Propp but wrote for no motive but money.

There?s a term George Orwell coined to describe this kind of writing ? prole entertainment. If you don?t know this term, you should ? be forewarned: it is not complimentary.

A Few Words About Culture and Change

Despite the efforts of culture critics such as Neil Postman to warn us of the danger of allowing ourselves to be seduced ? either by a particular medium or by the power of technology itself to change our lives in unexpected ways, human culture continues to embrace the changes to our lives ? and our art ? wrought by new technologies and media as rapidly as they appear. (For the well informed, that word ?wrought? has special meaning given its reference to Samuel F. B. Morse). We embraced the telegraph, the radio, film, then television, and most recently, the Internet: all brought with them not only new methods of communication but also necessarily changes in the way we think about and use (or think we can use) information.

This has clear implications for our appreciation of language ? the medium (in a slightly different meaning of the word) for writers ? especially poets ? for whom a word, to invert a famous saw, might mean a thousand pictures. So for my friend Sam, and to those like him who have felt the need to abandon this medium we all love so dearly ? language ? I feel especially pained. He and I gave talks in the late 1980?s that warned teachers and professors all over the country that the medium we treasured ? the written/printed word ? would likely be subsumed by the power of other media delivered via newer technologies.

Never have I wished more that we?d been wrong than as I write this.

The Pragmatic Artist

As media and technology savvy as we?ve always been, both Sam and I have embraced new media wholeheartedly ? fully aware that Merton?s Law dogged our every step. When Sam posted the link to his latest blog post on Facebook (natch), friends and colleagues ? known in both the real and virtual worlds ? weighed in with sympathy, encouragement and commiseration. In the comment thread on his post, I got into a dialogue (ah, Plato ? show of hands as to those who?ve read him? Anyone? Bueller?) with the talented singer, composer and musician Wendie Colter concerning Sam?s decision to abandon poetry. I include below part of our discussion:

Wendie: Jim ? artists make art for themselves first and foremost. But I maintain it can?t exist in a vacuum. It needs an energy exchange to live. Payment is one form of energy exchange, just like applause, reviews, acknowledgement from a community of peers, etc. If an artist doesn?t receive at least one of those things to her satisfaction, it is beyond discouraging. I haven?t met one artist (and I was raised by artists) that didn?t have the desire to make art for their living as a primary life goal.

Me: Wouldn?t argue any of that Wendie. But artists also make art for the future ? it?s a strong motivation, to leave something behind, to be remembered ? that?s the area I?ll be addressing in my response to Sam. As for that vacuum you mention, I understand what you mean, but I?m one who believes no artist has to live in a vacuum ? and I believe there are options artists can take (Sam?s taken one, but he seems to think it must involve leaving one art form for another ? I disagree with that decision qualifiedly) ? and that those options, whether marketing, technological, or some mix of the two, offer artists the opportunity to promote ? or present ? their art in venues and in ways that might find them audiences.

Wendie?s argument ? that artists have to find an audience and make a living ? is both valid and powerful. And her career as a composer of music for television, film, and commercials bears out her commitment to finding a way to practice her art in a fashion that allows her to make a living practicing her art. Her response to my reply ? that an artist?s leaving one medium to practice another is a bitter experience ? is made clear below:

Wendie: Only thing I?d say to that is that to move away from one medium that you had your heart set on and your identity wrapped up in is sometimes necessary. Painful and heartbreaking, but necessary.

Sam, as his essay notes, has made that painful change from one medium to another, hoping that pictures will give him the artistic satisfaction he gets from words.

But at heart Sam is a writer ? as his output for Scholars and Rogues shows. Whether he can ever equate what he achieves with his camera with what he has achieved with his pen as a poet (I?m speaking metaphorically) is something only Sam can decide.

Perhaps his artistic decision is acceptance of a reality that I haven?t been able to accept yet. Perhaps what Sam has done is make a pragmatic decision that, like Wendie?s, allows him to follow an artist?s path and find an audience who appreciates his talent in ways that he never felt he achieved through his career as a poet.

Perhaps the word will die ? and with it the art of the word ? literature ? will die. So Sam?s poetry will have been a mistaken foray into a dead art form. This development is possible ? though not probable.

So in case language survives, however, here are some ideas that might be worthy of his consideration.

Writers can embrace marketing and technology

As one privy to Sam?s decision before he announced it publicly, I suggested to him that he consider combining his photos with his poems. Such projects expand his potential audience to include both those who appreciate photography and those who appreciate poetry. This is called cross marketing ? and is a proven way to reach multiple audiences.

Many writers use YouTube as a method of attracting new readers by offering interviews, readings, and talks about their work. Sam is one of the best readers I?ve ever seen ? and he could introduce readers to his poetry ? as well as give talks about his poetry ? or poetry in general (his understanding of the genre is, as you?d expect, keen) that could help him build an audience. He could even create videos that combine his poetry with his photography ? and attract readers to his work as well as combine his artistic interests.

Why we write?or don?t?

The story of literature, particularly poetry, is one of unpredictability. Poets have come into and gone out of fashion (John Donne), had their works bowdlerized in the name of ?improvement? (William Shakespeare), and enjoyed great acclaim in their lifetimes only to become more famous for their lives than for their work (Lord Byron).

What I?m saying is, one never knows how one?s work will be received by future generations. That may seem pompous and idealistic, but as the poet said, ?Who shoots at the midday sun?.?

So I have encouraged Sam to work at finding publishers of his work ? even if that means working with a small, independent publisher ? who?ll care about his work ? and him ? and who?ll work with him to get his work out there so that it might be discovered ? either in his lifetime or later. As I mentioned in my response to Wendie, and as I often remind my wife Lea, a gifted artist herself, artists create for the future as much as for now.

The hard part of being an artist is accepting that we won?t necessarily achieve the sort of acclaim we may think we deserve in our lifetimes.

Harder still, though, is to leave a body of work as fine as Sam?s poetry in a drawer without finding an outlet for it ? especially in an age when finding such outlets is more possible than ever thanks to that very technology I spoke of earlier.

As much as I wish Sam well in his new artistic venture as a photographer, I hope he?ll consider finding publishing homes for his books of poetry. They are, to paraphrase a poet who labored in obscurity only to become after she was long dead a major American writer, his letters to the world.

They are fine letters ? I hope he?ll offer them to be read.

XPOST: The New Southern Gentleman

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Source: http://scholarsandrogues.com/2013/03/27/why-we-write-or-dont/

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