lunes, 17 de enero de 2011

Modelizan el riesgo de muerte por atropellos

Modelizan el riesgo de muerte por atropellos

Investigadores de la Unidad de Investigación y desarrollo de sistemas de seguridad de automóviles (INSIA) de la Universidad Politécnica de Madrid (UPM) han creado un modelo multivariante que identifica y explica la influencia de los factores del riesgo de muerte por atropello usando datos de casos reales ocurridos en Madrid.
Simulación de un atropello, secuencia de impactos. Fuente: INSIA-UPM
Los peatones son los usuarios más vulnerables de las vías públicas, lo que hace que la mortandad en la población mundial por accidentes de atropello sea alta y creciente. En España, como en otros países de la Unión Europea, se vienen tomado una serie de medidas para reducir el número de estos accidentes y sus consecuencias, y los resultados en los últimos años han sido alentadores.
Mediante un planteamiento multidisciplinario, investigadores de la Unidad de Investigación de Accidentes del INSIA-UPM han desarrollado un modelo multivariante que es capaz de identificar los parámetros de mayor influencia sobre el riesgo de muerte por atropello y sugerir en qué medida estas variables afectan a la probabilidad de fallecimiento. Para esto han creado una base de datos que contiene información detallada de atropellos reales ocurridos en Madrid, obtenida mediante recogida de información en el lugar del accidente, reconstrucciones con técnicas avanzadas y análisis en profundidad.
La elaboración de esta base de datos ha sido posible gracias a la colaboración de la Policía Municipal de Madrid y el equipo de emergencias del SAMUR, y contiene una muestra de 108 atropellos ocurridos en Madrid entre los años 2002 y 2005 con información detallada de la escena del accidente, huellas, datos y deformaciones del vehículo, información del peatón, sus lesiones y los mecanismos más probables de generación de las mismas.
De estos 108 casos se han seleccionado aquellos que cumplían las siguientes características: haberse producido en zona urbana; que el tipo de vehículo implicado sea turismo, monovolumen o todoterreno; y que el peatón haya impactado con la parte frontal del vehículo, resultando éste herido o fallecido como consecuencia del accidente. Tras esta selección, 50 atropellos que cumplían todos los requisitos mencionados han sido considerados para crear el modelo.
El modelo multivariante tiene dos componentes: (1) un árbol de clasificación que selecciona y caracteriza las variables, identificando sus interacciones y (2) una regresión logística binaria que cuantifica la influencia de las variables e interacciones que resultan del árbol. El modelo global representa una herramienta de gran utilidad para identificar, predecir y cuantificar los efectos de las medidas potenciales dirigidas a la reducción de las lesiones en los peatones atropellados.
Los resultados obtenidos con este modelo permiten concluir que la velocidad de atropello, dentro de los rangos en los que se produce la mayoría de los accidentes considerados en la muestra (30 – 60 km/h), no es el único factor determinante para predecir el riesgo de muerte del peatón, sino su interacción con otros parámetros y en este caso en concreto, con la altura del frontal del vehículo. Además, la trayectoria, velocidad o punto de impacto de la cabeza no dependen únicamente de la velocidad de atropello, sino también del punto en el que impacta la cadera del peatón (por debajo o por encima del frontal del capó, deslizando o no).
Estos resultados(1) han sido publicados en la revista “International Journal of Automotive Technology” y, si bien las conclusiones están limitadas al tamaño y características de la muestra, la metodología y el enfoque multidisciplinario que se han utilizado servirán para adoptar las medidas más adecuadas dirigidas a la mejora de la seguridad de los peatones.
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Referencia bibliográfica:
Badea, A., Furones, A., Paez, F. J., Gonzalez, C.. Multivariate modeling of pedestrian fatality risk through on the spot accident investigation. International Journal of Automotive Technology 11 (5): 711-720. Oct 2010

Notas placenteras

PSICOBIOLOGÍA
Notas placenteras
14/01/2011

La capacidad de la música de provocar reacciones fisiológicas es sabida, mas quedaba por explorar por qué ciertas melodías causan un efecto placentero en las personas similar a la comida o las relaciones sexuales. La Novena sinfonía de Beethoven, las Cuatro estaciones de Vivaldi o Moby Dick de Led Zeppelin, fueron algunas de las composición que investigadores del Instituto Neurológico de Montreal de la Universidad McGill emplearon para demostrar que los seres humanos somos capaces de obtener placer a través de estímulos abstractos. “La música, un estímulo abstracto, puede despertar sentimientos de euforia y el deseo, de forma similar a las recompensas tangibles como comer, las drogas o el sexo y que afectan al sistema dopaminérgico estriatal”, indican los autores del estudio.
El placer que origina la música se produce también con anticipación, es decir, aparece incluso antes de oír la composición. Así, el cerebro de los probandos que iban a escuchar su canción favorita liberaba dopamina justo antes de deleitarse con la melodía.
Para la medición se empleó una combinación de técnicas de tomografía por emisión de positrones (TEP) y de resonancia magnética funcional de imágenes cerebrales (IRMf). De tal manera se capturaron en línea y de forma conjunta las intervenciones de cada región cerebral en momentos concretos de la sesión musical. Se comprobó una disociación funcional en los probandos al escuchar su melodía preferida: el caudado aparecía más involucrado en la anticipación, mientras que el núcleo accumbens destacaba en el pico de respuesta emocional a la música.
Tales resultados indican que el placer intenso como respuesta al estímulo musical puede provocar la liberación de dopamina en el sistema estriatal. Además, demuestran que la anticipación de una recompensa abstracta puede originar la liberación de dopamina en una vía anatómica distinta de la que se asocia con el placer máximo en sí. Según los investigadores, el estudio ayuda a comprender por qué la música goza de un gran valor en las sociedades humanas.
“Es la primera vez que se demuestra que la recompensa abstracta, como la música, puede  provocar la liberación de dopamina. El estudio allana el camino para futuros trabajos sobre las recompensas no tangibles que los humanos consideran gratificantes por razones complejas”, concluye Zatorre.



Fuente: Montreal Neurological Institute and Hospital
Más información en Nature Neuroscience

La historia de Europa, reflejada en los árboles

PALEOCLIMA
La historia de Europa, reflejada en los árboles
17/01/2011

  • Los cambios climáticos registrados en los anillos de los árboles se relacionan con sucesos importantes de la historia europea, como la pandemia de la peste negra. (Foto izquierda: Wikimedia Commons; Foto derecha: Arnoldius, Wikimedia Commons).

Las variaciones climáticas han influido en la productividad agrícola, el riesgo de enfermedad y los conflictos de las sociedades preindustriales. Sin embargo, la distinción entre los efectos ambientales y los antropogénicos en las civilizaciones históricas plantea dificultades debido a la escasez de datos paleoclimáticos precisos.

Mediante el análisis de los anillos de crecimiento de los árboles (dendrocronología), un estudio ha reconstruido la variabilidad estival de las precipitaciones y temperaturas del centro de Europa durante los últimos 2500 años. Aunque el calentamiento global actual carece de precedentes, las variaciones hidroclimáticas de los últimos años han sido superadas en magnitud y duración en el pasado.

Los periodos de prosperidad del Imperio Romano y la Edad Media coinciden con años de veranos húmedos y calurosos. Por otro lado, las sequías prolongadas, las olas de frío y otros cambios en el clima debieron influir en los desórdenes históricos  del continente, como las invasiones bárbaras, que terminaron con el Imperio romano, o las hambrunas y las plagas de la Edad Media, que acabaron con la vida de numerosas personas.

Los autores del estudio sugieren que las circunstancias históricas pueden servir de ejemplo para orientar las medidas políticas y fiscales para mitigar el cambio climático previsto en el futuro.



Fuente: ScienceNow

Más información: Science

Jobs Takes Sick Leave at Apple Again, Stirring Questions

Jobs Takes Sick Leave at Apple Again, Stirring Questions


SAN FRANCISCO — Steven P. Jobs, the visionary co-founder and chief executive of Apple, is taking a medical leave of absence, a year and a half after his return following a liver transplant. The leave raises questions about both his long-term prognosis and the leadership of the world’s most valuable technology company.
Justin Sullivan/Getty Images
Steven P. Jobs, Apple’s chief executive, at the company’s headquarters in Cupertino, Calif., last October.


r. Jobs, 55, who recovered from pancreatic cancer after surgery in 2004, has not appeared at public events since October, and has looked increasingly frail in recent weeks, according to people who have seen him.
An Apple spokeswoman, Katie Cotton, said Apple would have no further comment beyond a brief public statement in which Mr. Jobs announced he was turning daily oversight of the company’s operations over to the chief operating officer, Timothy D. Cook.
While Apple and Mr. Jobs provided no more details of his illness, Mr. Jobs suffers from immune system problems common in people who have received liver transplants, said a person who knows him well, but who requested anonymity in order to maintain a relationship.
As a result, his health suffers from frequent “ups and downs,” the person said. Mr. Jobs, who has tried to keep his condition private, has in recent weeks begun a down cycle. Mr. Jobs has reduced his trips to the office, coming in about two days a week, and has appeared increasingly emaciated, the person said. He has frequently had lunch in his office, rather than in the company cafeteria, the person said.
Mr. Jobs said he would remain chief executive and said he hoped to return to Apple as soon as he could. Medical experts said that recipients of liver transplants often suffered from a variety of medical problems that were not life-threatening. According to statistics compiled in 2009 by the federal government, among patients who receive liver transplants, 20.7 percent die in the first three years, on average.
Mr. Jobs is taking a leave at a critical time for Apple. The company has outflanked most of its rivals in the technology industry with the iPhone and the iPad, which have been blockbuster hits with consumers. But giants like Google, Microsoft and Samsung have narrowed Apple’s lead or even surpassed the company by some measures.
Mr. Jobs’s leave is certain to cause anxiety with investors and consumers, because of the heightened competition the company faces. Perhaps more than any other chief executive, he is seen as inseparable from his company’s success.
“He may be the most vital C.E.O. of our era,” said Michael Useem, a professor at the Wharton School at the University of Pennsylvania and director of its Center for Leadership and Change Management.
Analysts noted that unlike his previous leave, when Apple said Mr. Jobs would be gone for six months, this time Mr. Jobs did not specify how long he would be out. “It raises the bigger question about whether he’ll ever return,” A. M. Sacconaghi Jr., an analyst with Sanford C. Bernstein & Company, said.
Shares of Apple immediately fell on foreign exchanges Monday, decreasing 7.6 percent in Frankfurt. Financial markets in the United States were closed on Monday in observance of Martin Luther King’s Birthday.
“It is natural that investors will expect the worse,” said Charles Wolf, an analyst with Needham & Company, adding that Apple has a history of “minimal disclosure” and “obfuscating” details about Mr. Jobs’s health.
During his previous leave of absence, Apple kept details of Mr. Jobs’s health private, prompting criticism among some shareholders who contended that the company had an obligation to be more forthcoming with information.
In his message to the staff on Monday, Mr. Jobs said, “My family and I would deeply appreciate respect for our privacy.”
Mr. Jobs announced his leave on Monday in an e-mail to employees that said he was stepping aside “so I can focus on my health” but would continue to be involved in strategic decisions at the company. “I love Apple so much and hope to be back as soon as I can,” Mr. Jobs wrote in the message, which was made public by Apple.
Mr. Cook, 50, will run day-to-day operations, Mr. Jobs said. Mr. Cook performed the same duties during Mr. Jobs’s medical leave in 2009.
“I have great confidence that Tim and the rest of the executive management team will do a terrific job executing the exciting plans we have in place for 2011,” Mr. Jobs wrote.
Mr. Jobs is known as a perfectionist, an exacting taskmaster who demands meticulous attention to detail, a management style that makes him difficult to work for, but which also helped Apple develop must-have products.
He is said to pay close attention to major decisions like whether Apple should develop a phone before a tablet, for example. He also pays attention to the most picayune cosmetic details, like ensuring that the colors of Google’s logo were exactly right on early versions of the iPhone.
He is credited with anticipating the desires of consumers time and again, leading Apple to create one breakthrough product after another. During most of his last absence, Mr. Jobs remained in almost daily telephone contact with other top executives as he monitored the progress of the iPhone 4 and the iPad. He was out of contact for a brief period only while recovering from his transplant.
    Mr. Wolf said that regardless of whether Mr. Jobs returned to Apple, the company would probably continue doing well for the foreseeable future, although its long-term prospects were more uncertain.

“Right now Apple has a management team that is one of the greatest in American business,” Mr. Wolf said. “Whatever trajectory the company is on will continue for two to five years, regardless of whether Steve comes back.”
Still, Apple faces increasing competition, especially in the smartphone market, where handsets powered by Google’s Android software recently began outselling the iPhone in the United States. Some analysts said the rise of Android led to Apple’s recent decision to begin offering the iPhone on Verizon Wireless starting next month, ending more than three years of exclusivity on AT&T.
Apple also faces sharper competition in tablet computers. The company’s iPad, introduced last spring, became an instant hit with consumers. But less than a year later, companies like Samsung, Research In Motion, Motorola and others have introduced or announced a string of credible competitors.
Analysts have confidence in the executive team because during Mr. Jobs’s 2009 leave, Mr. Cook successfully steered the company as it developed critical products. “Last time, Tim elevated his status with shareholders and employees,” Mr. Sacconaghi said. “The company did very well in Steve’s absence and various constituencies were pleased with that.”
In recent months, Mr. Jobs has looked increasingly frail and has sometimes needed to lean on others while walking, according to people who have seen him. He was expected to appear at an announcement with Rupert Murdoch, chief executive of the News Corporation, this week, but that event was postponed. The event was scheduled to announce a new publication for the iPad.
Medical experts say a variety of problems could affect someone with a liver transplant.
Dr. Lewis W. Teperman, the director of transplant surgery and vice chairman of surgery at the Langone Medical Center of New York University, said: “It’s very common for transplant patients to have issues that are not life-threatening. We give them very strong, high-powered medications, immuno-suppressants, to prevent rejection.” Dr. Teperman said he had no knowledge of Mr. Jobs’s case.
Side effects from the drugs include high blood sugar and diabetes, kidney damage, diarrhea, high blood pressure, high blood fats and cholesterol, rashes and low counts of white blood cells. The drugs leave patients prone to infection.
Dr. Teperman said it was extremely rare for a liver transplant to be totally rejected. The original reason for Mr. Jobs’s transplant was never publicly disclosed. At the time, doctors not involved in his case said the most likely reason was that his pancreatic cancer had spread to his liver. If that was the case, it was possible that cancer had recurred.
“There are lots of bumps in the road with transplantations, and people usually get through them,” he said.
    

‘The Social Network’ Dominates Golden Globes



‘The Social Network’ Dominates Golden Globes

Lucy Nicholson/Reuters
The producers of “The Social Network” with their Golden Globe for best picture, drama. From left, Kevin Spacey, Cean Chaffin, Dana Brunetti, Scott Rudin, and Michael De Luca. More Photos »
BEVERLY HILLS, Calif. — What can be the silliness of the Golden Globes matched up with the seriousness of the critics on Sunday night as “The Social Network” took the prize for best drama, Colin Firth was named best dramatic actor for “The King’s Speech” and Natalie Portman danced away with the award for best actress in a drama at the entertainment industry’s second-favorite awards show.
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Christian Bale, who plays the drug-addicted ex-boxer Dicky Eklund in “The Fighter.” More Photos »
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The comedian Ricky Gervais, the night’s host. More Photos »
“The Social Network” also won top prizes for its director, David Fincher, and its writer, Aaron Sorkin, making it the evening’s big winner.
In a moving touch, the final award for best movie drama was presented by Michael Douglas, who has fought his way through treatment for throat cancer that was diagnosed not long before the awards season got under way.
“There’s got to be an easier way to get a standing ovation,” said Mr. Douglas, who spoke little but sounded good, and stood out as the kind of trouper Hollywood and its fans both love.
Ms. Portman, who wore neither black nor white — her theme colors of late — but pink, won an almost inevitable prize for her performance as a ballerina on a death spiral in “Black Swan.” That film, critically acclaimed and heavily promoted, has been surging at the box office, giving it the kind of alignment that points toward a strong Oscar presence in coming weeks.
Almost as inevitably, Mr. Firth won for his portrayal of a stammering George VI. His thanks built up to some shaky words of gratitude for Harvey Weinstein, the Hollywood executive who has been a master at landing his pictures in the spotlight at the Globes and Oscars alike.
Melissa Leo and Christian Bale landed some blows by winning supporting actress and actor awards for “The Fighter,” a classic boxing story. The movie starred Mark Wahlberg, who did not win a prize as Micky Ward, a light welterweight champion who was coached by a drug-addicted brother, played by Mr. Bale.
In accepting his prize for writing “The Social Network,” Mr. Sorkin threw a barrage of gratitude at an inner circle of Hollywood operatives that included Sony Pictures executives, his agents at William Morris Endeavor, his producer Scott Rudin and even his publicist. But he also remembered to toss some conciliatory words at Mark Zuckerberg, the Facebook co-founder who was made to look less than admirable in the unauthorized film but did not put any legal roadblocks in its way.
“You turned out to be a great entrepreneur, a visionary and an incredible altruist,” Mr. Sorkin said.
After making numerous disconcertingly off-kilter nominations in the best musical or comedy category — Johnny Depp was twice-nominated for his work in “Alice in Wonderland” and “The Tourist,” neither of which seemed quite to fit — the Hollywood Foreign Press Association, whose 80 or so mostly freelance writers present the awards, redeemed itself by giving its lead award in the category to “The Kids Are All Right.”
A critical favorite, that film also won an acting award for one of its stars, Annette Bening. At the same time, Paul Giamatti won an acting award for the semi-serious comedy “Barney’s Version,” about a middle-aged man confronting his unraveling life.
A bit of a snub came with the presentation of the Globe for best foreign language film to “In a Better World,” from Denmark. One of the nominees, “Biutiful,” which stars Javier Bardem and is from Spain and Mexico, has had an early awards-season push behind it.
As always, the awards show, in the grand ballroom of the Beverly Hilton, wore thin as the plethora of awards — for movies and television both, plus those special prizes for comic categories — piled up and were spread around. There was a little something for Jim Parsons, as best comic actor in “The Big Bang Theory,” and best comic actress for the absent Laura Linney in “The Big C.”
It was a big night for Fox’s “Glee,” which picked up the best musical or comedy series award, as well as a pair of acting awards for Jane Lynch and Chris Colfer.
The Globes show only occasionally sank to the more inevitable movie-season jokes about Mr. Zuckerberg’s billions (“Heather Mills calls him the one that got away,” said Ricky Gervais, the show’s sharp-tongued host) and severed limbs (Steve Carell joked that he would have given his right arm to have written “127 Hours”).
Mr. Gervais virtually disappeared from the later stages of the show, leaving the presenters mostly to fend for themselves. Some did better than others.
Matt Damon fell flat with some schtick about being a young guy who had to ask around about Robert De Niro’s bona fides, as Mr. De Niro received his Cecil B. DeMille award for lifetime achievement. Mr. De Niro, 67 and only a little younger than the Globes, which are in their 68th year, took off his glasses and shot back, “And I loved you in ‘The Fighter.’ ” In which, of course, Mr. Damon did not appear.
Robert Downey Jr. summed up the show’s vibe as being “hugely mean-spirited” and mildly sinister, then upped the ante with sexual innuendo directed at the nominees for best actress in a motion picture, comedy or musical — Ms. Bening, Anne Hathaway, Angelina Jolie, Julianne Moore and Emma Stone — even as he introduced them.
Ms. Bening, whose spiky hair-do roughly matched that of Al Pacino — perhaps not lost on the camera operator who panned to his table as she spoke — won for her portrayal of an acidic lesbian mother in “The Kids Are All Right.”
Mr. Pacino won for his portrayal of Jack Kevorkian in the television film “You Don’t Know Jack,” while Claire Danes won for portraying an autistic woman in “Temple Grandin,” both of which helped keep HBO’s Globe dominance alive. “Toy Story 3,” from Disney’s Pixar unit, won for best animated feature, which was no surprise but certainly kept the film on track for what is expected to be a strong showing at the Oscars.
“Carlos,” about the terrorist Carlos the Jackal, won best televised movie or mini-series, for the Sundance Channel, one-upping HBO, which had three nominees in the category.
Steve Buscemi, one of many old film hands who have been turning to television as the movie world has diminished, picked up an award as the lead actor in HBO’s “Boardwalk Empire.” The show was also named best dramatic series.
In the first round of awards Katey Sagal won for best actress in a dramatic television series for her portrayal of the biker matriarch Gemma Morrow in “Sons of Anarchy” on FX.
The ragtag writers group that gives the Globes prompted even more than the usual giggles with some of its nominations this year, including three for the critically abused “Burlesque” and three for “The Tourist,” which was nominated for best comedy or musical despite its being neither. That added to the widely held belief that the press association nominates based more on red-carpet currency than performance. Cher, a star of “Burlesque,” didn’t take the bait, but Ms. Jolie, nominated for her work in “The Tourist,” gamely showed up, though she did not win.
Coming into the ceremony “The Fighter,” directed by David O. Russell, was perhaps the picture with the most to gain. A late-season release, it had six nominations, including one for best drama, and was positioned for the kind of come-from-behind push that left “Crash,” another dark horse, with a best-picture Oscar in 2006.
Two front-runners, “The King’s Speech” and “The Social Network,” had more to lose. Both were heavily nominated by the press association, and had already done well with awards from the critics. But both were looking for a show of strength to keep from slipping. “The Social Network,” with six nominations, picked up its first award for its score, by Trent Reznor and Atticus Ross.
(On the red carpet, Jesse Eisenberg, nominated for his portrayal of Mr. Zuckerberg, allowed that he still had not met Mr. Zuckerberg. “I’d really like to, though.”)
One film with nothing on the line: “True Grit,” the somber western that has been burning up the box office and is expected to be a player at the Oscars. But the film did not receive a single nomination by the press association.
In truth, the Globes do not predict much. Last year’s Globe winner for best drama was “Avatar”; for best musical or comedy it was “The Hangover.” But “The Hurt Locker” walked off with the best-picture Oscar.
A bit of inside action involved a hot dispute between the press association and Dick Clark Productions, which has long produced the ceremony, broadcast on NBC. In November the press association sued Dick Clark Productions and others for what it called an attempt to abscond with the awards by going around the association to reach a new eight-year broadcast agreement with NBC. The Dick Clark company sharply challenged the claim.
In another go-round, a longtime spokesman for the Globes, Michael Russell, on Thursday filed suit in Los Angeles County Superior Court against the press association and Phil Berk, its president. In the suit, Mr. Russell claimed he was wrongfully terminated from his publicity job partly because he had objected over the years to “unethical and potentially unlawful” deals under which members of the nonprofit association profit from the ceremony, sometimes by accepting payments from studios or producers to lobby for votes among their friends. Mr. Berk and the association dismissed the claims as baseless.
As Diane Warren picked up an award for her song “You Haven’t Seen the Last of Me” from “Burlesque” — yes, it had a winner — she dedicated the prize to Ronni Chasen. It was another inside moment: Ms. Chasen, a publicist who had represented Ms. Warren, was murdered on her way home from the “Burlesque” premiere in November.

En este día...

On This Day in HistoryMonday, January 17th
The 017th day of 2011.
There are 348 days left in the year.
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Today's Highlights in History
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On Jan. 17, 1893, Hawaii's monarchy was overthrown as a group of businessmen and sugar planters forced Queen Liliuokalani to abdicate. (Go to article.)
On Jan. 17 , 1899, Al Capone , the American gangster and prohibition era crime leader , was born. Following his death on Jan. 25 , 1947, his obituary appeared in The Times. (Go to obit. | Other Birthdays)
Editorial Cartoon of the Day

On January 17, 1863, Harper's Weekly featured a cartoon about the Civil War. (See the cartoon and read an explanation.)

On this date in:
1562 French Protestants were recognized under the Edict of St. Germain.
1706 Statesman and inventor Benjamin Franklin was born in Boston.
1806 Thomas Jefferson's daughter, Martha, gave birth to James Madison Randolph, the first child born in the White House.
1893 Hawaii's monarchy was overthrown.
1893 Rutherford B. Hayes, the 19th president of the United States, died in Fremont, Ohio, at age 70.
1899 Gangster Al Capone was born in Brooklyn, N.Y.
1945 Soviet and Polish forces liberated Warsaw during World War II.
1945 Swedish diplomat Raoul Wallenberg, credited with saving tens of thousands of Jews during the Holocaust, was taken into Soviet custody in Budapest, Hungary. (His fate has never been determined.)
1946 The United Nations Security Council held its first meeting.
1977 Convicted murderer Gary Gilmore was shot by a firing squad at Utah State Prison in the first U.S. execution in a decade.
1994 A magnitude 6.7 earthquake struck Southern California, killing at least 61 people and causing $20 billion worth of damage.
1995 A magnitude 7.2 earthquake devastated the city of Kobe, Japan; more than 6,000 people were killed.
1997 A court in Ireland granted the first divorce in the Roman Catholic country's history.
1998 President Bill Clinton became the first U.S. president to testify as a defendant in a criminal or civil suit when he answered questions from lawyers for Paula Jones, who had accused Clinton of sexual harassment.
2001 Faced with an electricity crisis, California used rolling blackouts to cut off power to hundreds of thousands of people.

Current Birthdays
Michelle Obama turns 47 years old today.

AP Photo/Alex Brandon First lady Michelle Obama turns 47 years old today.

80 James Earl Jones
Actor
80 Don Zimmer
Baseball coach
72 Maury Povich
Talk show host
69 Muhammad Ali
Boxing Hall of Famer
63 Mick Taylor
Rock musician (Rolling Stones)
57 Robert F. Kennedy Jr.
Lawyer, environmental activist
56 Steve Earle
Rock singer
55 Paul Young
Rock singer
54 Steve Harvey
Actor, comedian
52 Susanna Hoffs
Rock musician, singer (The Bangles)
49 Jim Carrey
Actor
45 Joshua Malina
Actor ("The West Wing," "Sports Night")
42 Naveen Andrews
Actor ("Lost")
40 Kid Rock
Rapper
31 Zooey Deschanel
Actress
Historic Birthdays

Al Capone

1/17/1899 - 1/25/1947
American gangster

(Go to obit.)

62 Philip II of Burgandy
1/17/1342 - 4/27/1404
French Duke


59 Guarino Guarini
1/17/1624 - 3/6/1683
Italian architect


69 Jacques-Francois Blondel
1/17/1705 - 1/9/1774
French architect


29 Anne Bronte
1/17/1820 - 5/28/1849
English novelist


82 David Lloyd George
1/17/1863 - 3/26/1945
English Prime Minister


80 Mack Sennett
1/17/1880 - 11/5/1960
American director/producer


69 Glenn Martin
1/17/1886 - 12/4/1955
American airplane inventor


61 Nevil Shute
1/17/1899 - 1/12/1960
English/Australian writer


78 Robert M. Hutchins
1/17/1899 - 5/14/1977
American educator


67 Nora Kaye
1/17/1920 - 2/28/1987
American ballerina


34 Thomas Dooley
1/17/1927 - 1/18/1961
American physician/author


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SOURCE: The Associated Press
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Secretos de la cirugía laparoscópica segura: consideraciones anestésicas y quirúrgicas

Secretos de la cirugía laparoscópica segura: consideraciones anestésicas y quirúrgicas
En los últimos años, la cirugía laparoscópica ha ganado popularidad en la práctica clínica. El elemento clave en la cirugía laparoscópica es la creación del neumoperitoneo y el dióxido de carbono se usa comúnmente para la insuflación. Este neumoperitoneo pone en peligro el sistema cardiopulmonar normal en gran medida. Cada cirujano laparoscópico debe entender las consecuencias de neumoperitoneo, de modo que sus efectos adversos pueden evitarse. El neumoperitoneo aumenta la presión sobre el diafragma, dando lugar a su desplazamiento cefálico y disminuyendo así el retorno venoso, lo que puede ser agravada por la posición del paciente durante la cirugía. No hay ninguna contraindicación absoluta de la cirugía laparoscópica, aunque podemos anticipar algunos problemas en las condiciones como la obesidad, el embarazo y la cirugía abdominal previa. En esta revisión se discuten algunos aspectos de la fisiopatología del neumoperitoneo de dióxido de carbono, sus consecuencias, así como las estrategias para contrarrestarlas. Además, proponemos algunas directrices para la cirugía laparoscópica segura.

Secrets of safe laparoscopic surgery: Anaesthetic and surgical considerations.
Srivastava A, Niranjan A.
J Min Access Surg 2010;6:91
In recent years, laparoscopic surgery has gained popularity in clinical practice. The key element in laparoscopic surgery is creation of pneumoperitoneum and carbon dioxide is commonly used for insufflation. This pneumoperitoneum perils the normal cardiopulmonary system to a considerable extent. Every laparoscopic surgeon should understand the consequences of pneumoperitoneum; so that its untoward effects can be averted. Pneumoperitoneum increases pressure on diaphragm, leading to its cephalic displacement and thereby decreasing venous return, which can be aggravated by the position of patient during surgery. There is no absolute contraindication of laparoscopic surgery, though we can anticipate some problems in conditions like obesity, pregnancy and previous abdominal surgery. This review discusses some aspects of the pathophysiology of carbon dioxide induced pneumoperitoneum, its consequences as well as strategies to counteract them. Also, we propose certain guidelines for safe laparoscopic surgery.

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Atentamente
Anestesiología y Medicina del Dolor

domingo, 16 de enero de 2011

Los matrimonios más felices son los que ayudan a crecer


Los matrimonios más felices son los que ayudan a crecer

Durante siglos, el matrimonio fue visto como una institución económica y social, en el que las necesidades intelectuales y emocionales de sus miembros no eran importantes para la supervivencia del matrimonio en sí mismo. Pero, en las relaciones actuales, la gente busca una pareja que le ayude a desarrollarse y a crecer. Esto es lo que afirman dos psicólogos estadounidenses especializados en el estudio del amor. Según ellos, las parejas que potencian la auto-expansión de sus miembros son las que más garantías tienen de perdurar y ser felices. Por el contrario, las personas que no ven su pareja como una fuente de crecimiento y de bienestar son las más propensas a ser infieles. Por Yaiza Martínez.
Los matrimonios más felices son los que ayudan a crecer
Un matrimonio duradero no siempre es un matrimonio feliz. Muchas parejas desgraciadas se mantienen unidas por los hijos, sus creencias religiosas u otras razones prácticas. Pero en la actualidad, muchas personas no se conforman sólo con estar con su pareja, sino que buscan una relación que tenga sentido y resulte satisfactoria.

Durante siglos, el matrimonio fue visto como una institución económica y social, en el que las necesidades intelectuales y emocionales de sus miembros no eran importantes para la supervivencia del matrimonio en sí mismo. Pero, en las relaciones modernas, la gente busca una pareja que, en definitiva, haga su vida más interesante.

Satisfacción y compromiso

Esto es lo que señala el psicólogo Arthur Aron, de la Stony Brook University de Nueva York, que lleva años estudiando el amor. Ya hablamos de él anteriormente en Tendencias21, a raíz de un estudio realizado por Aron y otros investigadores, en el que se demostró que el amor produce el mismo efecto analgésico que los calmantes.

Recientemente, el New York Times ha dedicado un artículo sobre los últimos trabajos realizados sobre las parejas modernas por Arthur Aron, en colaboración con el psicólogo de la Universidad Monmouth de Nueva Jersey, Gary W. Lewandowski Jr.

Ambos investigadores han estudiado la manera en que, actualmente, los individuos utilizan sus relaciones de pareja para acumular conocimientos y experiencias, siguiendo un proceso llamado “auto-expansión”.

Sus investigaciones han demostrado que, cuanto mayor sea la experiencia de “auto-expansión” que una persona pueda experimentar con su pareja, más satisfecha y comprometida estará dicha persona con su relación.

Crecer y ayudar a crecer

Para medir el grado de auto-expansión de cada individuo en su pareja, Lewandowski ha desarrollado uncuestionario específico, que contiene cuestiones como: “¿cuánto tiempo del que has pasado con tu pareja te ha llevado a aprender cosas nuevas?, ¿hasta qué punto conocer a tu pareja te ha hecho mejor persona? o ¿hasta qué punto tu pareja te ha ayudado a mejorar tus capacidades para hacer ciertas cosas? etc.

Según él, las respuestas obtenidas han revelado que la auto-expansión es, en la actualidad, esencial para tener una buena relación de pareja. Si tu pareja te ayuda a desarrollarte, pasa a tener una posición muy importante para ti.

Por otro lado, ser capaz de ayudar al otro miembro de pareja en su propia auto-expansión, resulta muy placentero para uno mismo.

Este concepto de auto-expansión, aunque justifica el placer que produce, por ejemplo, hacer cosas distintas a lo que normalmente hacemos, no tiene forzosamente que ver con lo “exótico”, aclaran los investigadores.

Las personas experimentan el crecimiento personal a través de sus parejas tanto con detalles como con grandes experiencias: si la pareja presenta nuevas amistades o le da a conocer sitios nuevos, etc.

Aumentar el sí-mismo

Por otro lado, Aron explica que, cuando uno se enamora, el sí-mismo también se amplía para incluir a la pareja en el auto-concepto, asimilando repentinamente papeles sociales e identidades que anteriormente no había tenido.

Los resultados de diversas investigaciones sugieren que, por esta razón, los esposos,
con el tiempo, acaban adoptando características del otro, y les cuesta más distinguir las diferencias entre ambos.

Los matrimonios más felices son los que ayudan a crecer
Esto fue constatado en un experimento llevado a cabo por Aron, en el que varios participantes se evaluaron a sí mismos y a sus parejas a partir de diversas características, como “ambicioso” o “artístico”.

Una semana más tarde, los voluntarios volvieron al laboratorio. En ese momento, se les presentó de nuevo su lista y se les pidió que señalaran en ella las características que les describían. Los participantes respondieron más rápidamente a esta pregunta con aquellas características que se daban tanto en ellos como en sus parejas.

Cuando las características describían sólo a uno de los miembros de la pareja, contestaron más despacio. Este retraso, aunque duró sólo milisegundos, sugiere según los investigadores que cuando una persona se siente particularmente cerca de otra, su cerebro se vuelve más lento en la distinción entre ambos.

Los científicos señalan que este hecho no significa que las personas se pierdan a sí mismas en el matrimonio, sino que crecen porque actividades, características y comportamientos que antes de su relación no habían formado parte de su identidad, se incorporan a ésta y se convierten en una parte esencial en su experimentación de la vida.

Según Lewandowski, una cuestión esencial para tener una relación perdurable y satisfactoria es la siguiente: “si tu pareja te está ayudando a ser mejor persona, estarás más satisfecho o satisfecha, y serás más feliz en tu relación”.

Otros elementos que también resultan esenciales en este sentido son el bienestar que produce estar con otra persona o una buena auto-estima, reveló otro estudio de Arthur Aron llevado a cabo en 2009.

Buscar alternativas

En el sentido contrario, Lewadowski y otros investigadores comprobaron, en dos estudios publicados en 2010 por el Journal of Social and Personal Relationships que los miembros de parejas con un bajo nivel de auto-expansión mostraban un mayor interés en buscar parejas alternativas.

En un estudio anterior, publicado en The Journal of Social Psychology, Lewadowski constató asimismo que la necesidad de realización y de auto-expansión dentro de una relación romántica puede predecir la propensión a ser infieles.

En este caso, fueron evaluados cinco tipos de variables de necesidad de realización (intimidad, compañerismo, sexo, seguridad e implicación emocional) y tres tipos de variables de auto-expansión (auto-expansión, inclusión del otro en uno mismo y potencial de auto-expansión) en 109 universitarios (50 hombres y 59 mujeres) con pareja.

Asimismo, se evaluó también el grado de propensión a la infidelidad en todos ellos. Tal y como los investigadores habían predicho, los resultados demostraron que cuando una relación no es capaz de cubrir ciertas necesidades o de proporcionar una gran auto-expansión al individuo, la propensión de éste hacia la infidelidad aumenta.