jueves, 20 de enero de 2011

El tipo de amistades de los adolescentes predice su éxito académico


El tipo de amistades de los adolescentes predice su éxito académico


En el momento en que los niños pasan de la escuela al instituto, los cambios en sus amistades pueden servir para predecir sus éxitos o problemas académicos, ha revelado un estudio realizado por especialistas de la Universidad de Oregón, en Estados Unidos.

Los investigadores constataron que los chicos y las chicas cuyos amigos son socialmente activos, pero respetuosos con las normas establecidas, rinden mejor en los estudios. Por el contrario, tener amigos con problemas de comportamiento está relacionado con una disminución del nivel académico.

Por último, el estudio también reveló que tener amigos con un buen comportamiento social y evitar a aquéllos con problemas sociales tiene un mayor efecto positivo en los resultados académicos que el hecho de tener amigos que saquen muy buenas notas.

Estos resultados fueron obtenidos a partir de una muestra de 1.278 estudiantes adolescentes, el 55% chicas, a los que se les pidió que dieran el nombre de sus tres mejores amigos. Para alcanzar sus conclusiones, los investigadores analizaron el comportamiento y los expedientes académicos de los participantes en el estudio y de los amigos seleccionados. 

Middle school is when the right friends may matter most

Academic success is boosted by way of pro-social friends and avoiding deviant peer, researchers say



 IMAGE: Marie-Helene Veronneau of the University of Oregon says that having pro-social friends helps middle school students do better academically.

Click here for more information.

EUGENE, Ore. -- (Jan. 12, 2011) -- As adolescents move from elementary school into their middle or junior-high years, changes in friendships may signal potential academic success or troubles down the road, say University of Oregon researchers.
A new study, appearing in the February issue of the Journal of Early Adolescence, found that boys and girls whose friends are socially active in ways where rules are respected do better in their classroom work. Having friends who engage in problem behavior, in contrast, is related to a decrease in their grades. Having pro-social friends and staying away from deviant peers proved more effective for academic payoffs than simply being friends with high-achieving peers.
The middle school/junior high years are a major transition for children, as students move away from grade-school classrooms led by one teacher every day into an environment of multiple classes with different teachers and opportunities to make new friends. This new study -- conducted by Marie-Helene Veronneau and Thomas J. Dishion of the UO Child and Family Center -- focused solely on the role played by friendship on academic achievement.
Their findings emerged from data collected in a longitudinal study of 1,278 students -- 55 percent of them girls -- done previously by center researchers. In that study, students named their three best friends. Instead of relying on student reports of their peers' behaviors and grades, researchers in the new study looked specifically at behavioral and academic records of the friends.
A surprise discovery was that girls who already were struggling academically in sixth grade actually suffered later when their chosen friends were already those making the highest grades, Veronneau said. "We don't know the mechanisms on why it is this way for girls, but we can speculate that girls compare themselves to their friends and then decide they are not doing very well. Perhaps this affects their self-efficacy and belief in their own abilities."
For girls already doing well in sixth grade, however, there was an opposite influence. "It could be for these girls, having friends who also are getting good grades, school is challenging and stimulating, and they end up doing better than expected," she said.
The study's findings clearly show that in the middle school years "a great deal of learning is taking place that is not being attended to," said Dishion, director of the Child and Family Center and professor of school psychology. "Puberty is taking place. The brain is changing rapidly. Kids' brains are almost wired to be reading the social world to see how they fit in, and the school is the arena for it."
These transitional years may be pivotal, Dishion said. In a previous longitudinal study, he said, he and colleagues looked at the impacts of peer relationships of young people at ages 13, 15 and 17 to look for predictive indicators of life adjustments at age 24. Those influences at age 13 -- going back to middle school -- were the most influential, he noted. While instruction is school is vitally important, he said, it may be that more eyes should be looking at shifting peer relationships.
In their conclusions, Dishion and Veronneau suggested that responsible adults -- at school and at home -- "should pay special attention" to changes in friendships and encourage students to pursue and participate in adult-supervised activities to promote pro-social relationships.
"Parents should pay attention to what their kids are doing and with whom they hang out," Veronneau said. "If parents notice that there is a shift in a child's friendship network, they should try to get to know those kids, talk with teachers and communicate naturally with their own child about where they are going and when they will be coming home."
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The research was supported through grants from the Social Sciences and Humanities Research Council of Canada to Veronneau and from the National Institute on Drug Abuse at the National Institutes of Health to Dishion.
About the Child and Family Center
The University of Oregon Child and Family Center staff is dedicated to understanding and promoting mental health and resilience within families in all cultural communities. The institute conducts research on social-emotional development from infancy through adolescence and provides innovative assessment, prevention, and intervention services for children and families.
Media Note: Five audio segments containing comments from the researchers may be obtained by sending an email request to jebarlow@uoregon.edu, stating your preferred format. They may be heard at: http://bit.ly/eI7u8u
Sources: Marie-Helene Veronneau, courtesy research associate, UO Child and Family Center, 541-346-4708, mariev@uoregon.edu; Thomas J. Dishion, professor of school psychology and director of the Child and Family Center, 346-3620 or 541-346-4805, dishion@uoregon.edu
Links:
Child and Family Center: http://cfc.uoregon.edu/index.htm
UO School Psychology Program: http://education.uoregon.edu/field.htm?id=34

¿Es verdad que las bebidas alcohólicas más oscuras producen peores resacas?


¿Es verdad que las bebidas alcohólicas más oscuras producen peores resacas?

La resaca también se conoce bajo el nombre de guayabo, ratón, cruda (en sudamérica), goma (Panamá), hangover (Inglaterra), Futsu-ka-yoi (Japón, significa borrachera del segundo día). El término médico es veisalgia: etimológicamente proviene de kveis, término noruego que significa intranquilidad después de una bacanal, yalgia, del griego, que significa dolor.
Si decidís empinar el codo, tened en cuenta el color de la bebida alcohólica que vais a escoger. Cuanto más oscura sea, peor podría ser vuestra resaca al día siguiente. La culpa de ello la tienen los llamados congéneres.
Es decir, si podéis escoger, es mejor emborracharse con vino blanco o vodka antes que hacerlo con whisky, vino tinto o coñac. Si ordenamos el alcohol en base a sus síntomas de resaca y por orden descendente, quedaría de tal manera: coñac, vino tinto, ron, whisky, vino blanco, ginebra, vodka y etanol ruso. Es decir, que los rusos sí que saben.

Pero ¿qué son los congéneres? Los congéneres son componentes biológicamente activos que contienen muchas bebidas. Y son importantes, aunque sólo nos fijemos en la cantidad de etanol. Por ejemplo, los polifenoles, y otros alcoholes, como el metanol, e histamina. Se producen junto con el etanol durante la fermentación o en el proceso de envejecimiento de la bebida.
Estos congéneres varían según el origen de los azúcares fermentados (mosto, remolacha azucarera, restos agrícolas, caña de azúcar, cereales…) y la actividad biológica de las levaduras. Su presencia es la que confiere a la bebida sus características organolépticas.
Se cree que los congéneres contribuyen a los efectos embriagantes de una bebida, y a la resaca subsiguiente. Se ha demostrado que la gente que bebe alcoholes basados en etanol puro, como el vodka, padecen menos síntomas de resaca que los que beben bebidas más oscuras, como whisky, coñac o vino tinto, todas las cuales tienen un contenido de congéneres mucho más elevado.
El metanol es el principal responsable de nuestras resacas. Si bien metabolizamos el metanol de una forma similar al etanol, el producto final es diferente.
El proceso de destilación disminuye la concentración de estas sustancias (como en el caso del vodka); pero existen bebidas en las que interesa potenciar sus carácteres organolépticos, como el brandy o el whisky, por lo que la concentración de metanol, acetaldehído, etc. se encuentra en concentraciones superiores.
El etanol genera acetaldehído, pero cuando el metanol se descompone, uno de los productos principales que se forman es el formaldehído, que es más tóxico que el acetaldehído y que puede provocar en concentraciones elevadas la ceguera y la muerte. El etanol inhibe el metabolismo del metanol, lo que puede ser motivo de que “un clavo quite otro clavo”, y beber alcohol alivie los síntomas de la resaca.
Vía | Eureka / ¿Hay algo que coma avispas? de Mick O´Hare

La luz artificial afecta negativamente al sueño y a la salud



La luz artificial afecta negativamente al sueño y a la salud


La exposición a luz artificial durante el anochecer y a la hora de acostarse suprime en gran medida los niveles de melatonina en sangre y puede, por tanto, impactar negativamente en los procesos fisiológicos regulados por esta hormona, como el sueño, la termorregulación, la presión sanguínea o el metabolismo de la de glucosa.

Esto es lo que revela un estudio realizado por científicos de la Escuela Médica de Harvard, cuyos resultados ayudan a comprender cómo la exposición a la luz artificial puede afectar al organismo y al sueño humanos.

Según los investigadores, los resultados obtenidos demuestran que dicha exposición tiene un fuerte efecto de supresión sobre la melatonina, una hormona que se sabe está relacionada con los ciclos circadianos del cuerpo y con otros factores orgánicos.

En la investigación participaron 116 personas sanas de entre 18 y 30 años de edad a las que se expuso a iluminación general o a luz tenue durante ocho horas antes de dormir y durante cinco días consecutivos.

Muestras de sangre tomadas a los voluntarios demostraron que la exposición a iluminación general acortó en ellos la duración de la melatonina en 90 minutos, en comparación con la exposición a luz tenue. Además, la exposición a la iluminación general durante las horas corrientes del sueño suprimió la melatonina en más del 50%. 




Room light before bedtime may impact sleep quality, blood pressure and diabetes risk

New study shows indoor lighting has profound suppressive effect on the hormone melatonin

Chevy Chase, MD—According to a recent study accepted for publication in The Endocrine Society's Journal of Clinical Endocrinology & Metabolism (JCEM), exposure to electrical light between dusk and bedtime strongly suppresses melatonin levels and may impact physiologic processes regulated by melatonin signaling, such as sleepiness, thermoregulation, blood pressure and glucose homeostasis.
Melatonin is a hormone produced at night by the pineal gland in the brain. In addition to its role in regulating the sleep-wake cycle, melatonin has been shown to lower blood pressure and body temperature and has also been explored as a treatment option for insomnia, hypertension and cancer. In modern society, people are routinely exposed to electrical lighting during evening hours to partake in work, recreational and social activities. This study sought to understand whether exposure to room light in the late evening may inhibit melatonin production.
"On a daily basis, millions of people choose to keep the lights on prior to bedtime and during the usual hours of sleep," said Joshua Gooley, PhD, of Brigham and Women's Hospital and Harvard Medical School in Boston, Mass. and lead author of the study. "Our study shows that this exposure to indoor light has a strong suppressive effect on the hormone melatonin. This could, in turn, have effects on sleep quality and the body's ability to regulate body temperature, blood pressure and glucose levels."
In this study, researchers evaluated 116 healthy volunteers aged 18-30 years who were exposed to room light or dim light in the eight hours preceding bedtime for five consecutive days. An intravenous catheter was inserted into the forearms of study participants for continuous collection of blood plasma every 30-60 minutes for melatonin measurements. Results showed exposure to room light before bedtime shortened melatonin duration by about 90 minutes when compared to dim light exposure. Furthermore, exposure to room light during the usual hours of sleep suppressed melatonin by greater than 50 percent.
"Given that chronic light suppression of melatonin has been hypothesized to increase relative risk for some types of cancer and that melatonin receptor genes have been linked to type 2 diabetes, our findings could have important health implications for shift workers who are exposed to indoor light at night over the course of many years," said Gooley. "Further research is still needed to both substantiate melatonin suppression as a significant risk factor for breast cancer and determine the mechanisms by which melatonin regulates glucose metabolism."
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Other researchers working on the study include: Kyle Chamberlain of the University of Surrey in the United Kingdom; and Kurt Smith, Sat Bir Khalsa, Shantha Rajaratnam, Eliza Van Reen, Jamie Zeitzer, Charles Czeisler and Steven Lockley of Brigham and Women's Hospital and Harvard Medical School in Boston, Mass.
The article, "Exposure to room light prior to bedtime suppresses melatonin onset and shortens melatonin duration in humans," appears in the March 2011 issue ofJCEM.
Founded in 1916, The Endocrine Society is the world's oldest, largest and most active organization devoted to research on hormones and the clinical practice of endocrinology. Today, The Endocrine Society's membership consists of over 14,000 scientists, physicians, educators, nurses and students in more than 100 countries. Society members represent all basic, applied and clinical interests in endocrinology. The Endocrine Society is based in Chevy Chase, Maryland. To learn more about the Society and the field of endocrinology, visit our site at www.endo-society.org.

Facebook: un paso más hacia la madurez


Posted: 19 Jan 2011 02:56 PM PST
Parece que va llegando la normalización del fenómeno de las redes sociales. Lo demuestra que haya encontrado en Reuters los resultados de la investigación que quería dejaros hoy.
Sus conclusiones son contraintuitivas, sorprendentes y desmienten el mito de que niños/as y jóvenes ocultan lo que hacen en las redes sociales a los padres. Así, según Campbell, director ejecutivo de la compañía Kaplan, responsable del estudio sobre redes sociales entre 2313 alumnos de 16 a 18 años,solamente un 38% de los jóvenes ignora las solicitudes de amistad de sus padres en Facebook. O lo que es lo mismo:
“En contra de lo que podría parecer, prácticamente dos tercios de los adolescentes americanos se sienten lo suficientemente cómodos con sus padres como para tenerles como amigos en Facebook.”
No siempre se trata de una cuestión de confianza  y en el 16% de las ocasiones, hacerse amigo de los padres era una condición impuesta por estos para dejarles dar de alta.
Para muchos jóvenes americanos (y diría que el resultado es aplicable a nuestro contexto), FB es una nueva oportunidad de permanecer independientes de sus padres, un paso más hacia la madurez, según los autores. Así, aunque en ocasiones padres y jóvenes deciden mantener mútuamente sus vidas separadas en Facebook, los mismos adolescentes que ignoran peticiones de amistad de sus padres, en un 82% de los casos, comentan que sus padres están implicados en sus vidas académicas.
Campbell describe Facebook como un paso natural en el “estar conectado” de las nuevas generaciones, que han crecido con Internet, confirmando lo que hemos dicho en muchas ocasiones aquí: negar el acceso de nuestros jóvenes a las redes sociales es limitarles en algo que es básico en su desarrollo, fundamental para construirse en un entorno hiperconectado.

Socialización virtual, Socialización no virtual y escuela
El estudio me ha hecho pensar, por último, en el papel de la escuela como entorno de socialización. Pensamos incluso, cuando no vemos claros los modelos de desescolarización o de Home schooling, en la importancia inestimable del entorno escolar durante el proceso de socialización. Creo que el uso de las redes sociales en las múltiples iniciativas autonómicas de “Escuela 2.0″  debería defenderse no solo en cuanto a que son poderosas herramientas de conocimiento, sinó también desde la perspectiva de que son medios de socialización importantes

Valor de QuantiFERON-TB Gold Test in Tube en el diagnóstico de tuberculosis pulmonar y extrapulmonar

Valor de QuantiFERON-TB Gold Test in Tube en el diagnóstico de tuberculosis pulmonar y extrapulmonar 
Enferm Infecc Microbiol Clin. 2010;28:685-9.
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En los últimos años se han desarrollado nuevas técnicas para el diagnóstico de infección tuberculosa, basados en la detección in vitro de interferon gamma frente a Mycobacterium tuberculosis. En las últimas guías ya aparecen estas técnicas de forma combinada a la prueba de Mantoux para el diagnóstico de infección latente tuberculosa. El objetivo de este estudio fué evaluar el papel del test de ELISA Quantiferon-TB Gold en el diagnóstico de la enfermedad tuberculosa activa y la concordancia con la prueba de la tuberculina

 

Bases biológicas de la adicción al tabaco: Implicaciones del tratamiento para dejar de fumar


Bases biológicas de la adicción al tabaco: Implicaciones del tratamiento para dejar de fumar
El consumo de tabaco llegó a ser común en todo el mundo después del descubrimiento de América. El tabaco es una planta lleva en sus hojas un alcaloide llamado nicotina, que es responsable no sólo de varios cambios fisiopatológicos en el cuerpo sino que también desarrolla tolerancia a su propia acción con el uso repetido. Los estudios sugieren que la alfa-4 beta-2 acetilcolina subtipo de receptor de nicotina es el principal receptor que media la dependencia a la nicotina. La nicotina actúa sobre estos receptores para facilitar la liberación de neurotransmisores (dopamina y otros), produciendo placer y la modulación del estado de ánimo. La exposición repetida a la nicotina desarrolla neuroadaptación de los receptores, lo que resulta en la tolerancia a muchos de los efectos de la nicotina. Los síntomas de abstinencia aparecen en suspensión del consumo de tabaco, que se caracterizan por irritabilidad, ansiedad, aumento de comer, disforia, y la desregulación hedónicos, entre otros. Fumar es también reforzado por el condicionamiento. Tratamientos farmacológicos para dejar de fumar deberían reducir los síntomas de abstinencia y bloquear los efectos reforzantes de la nicotina obtenida de fumar sin causar excesivos efectos adversos

Biological basis of tobacco addiction: Implications for smoking-cessation treatment
RC Jiloha.
Department of Psychiatry, G. B. Pant Hospital, Maulana Azad Medical College and University of Delhi, India
Indian Journal of Psychiatry  2010;52:301-307.  DOI: 10.4103/0019-5545.74303
Tobacco use became common all over the world after discovery of Americas. Tobacco, a plant carries in its leaves an alkaloid called nicotine, which is responsible not only for several pathophysiological changes in the body but also develops tolerance to its own action with repeated use. Studies suggest that the alpha-4 beta-2 nicotine acetylcholine receptor subtype is the main receptor that mediates nicotine dependence. Nicotine acts on these receptors to facilitate neurotransmitter release (dopamine and others), producing pleasure and mood modulation. Repeated exposure to nicotine develops neuroadaptation of the receptors, resulting in tolerance to many of the effects of nicotine. Withdrawal symptoms appear on stoppage of tobacco use, which are characterized by irritability, anxiety, increased eating, dysphoria, and hedonic dysregulation, among others. Smoking is also reinforced by conditioning. Pharmacotherapies for smoking cessation should reduce withdrawal symptoms and block the reinforcing effects of nicotine obtained from smoking without causing excessive adverse effects

Atentamente
Anestesiología y Medicina del Dolor

Actualizaciones cefalea

Actualizaciones

Cefalea
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Cefalea tensional
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Migraña
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Manejo terapéutico de las migrañas
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Cefalea en racimos

Cefalea

Protocolo diagnóstico de la cefalea de reciente comienzo
http://www.elsevier.es/watermark/ctl_servlet?_f=10&pident_articulo=13190428&pident_usuario=0&pident_revista=62&fichero=62v10n70a13190428pdf001.pdf&ty=1&accion=L&origen=medicine&web=www.medicineonline.es&lan=es

Protocolo diagnóstico de la cefalea crónica
http://www.elsevier.es/watermark/ctl_servlet?_f=10&pident_articulo=13190429&pident_usuario=0&pident_revista=62&fichero=62v10n70a13190429pdf001.pdf&ty=2&accion=L&origen=medicine&web=www.medicineonline.es&lan=es

Protocolo diagnóstico de la cefalea con fiebre
http://www.elsevier.es/watermark/ctl_servlet?_f=10&pident_articulo=13190430&pident_usuario=0&pident_revista=62&fichero=62v10n70a13190430pdf001.pdf&ty=3&accion=L&origen=medicine&web=www.medicineonline.es&lan=es

Protocolo terapéutico sintomático y preventivo de la cefalea tensional
http://www.elsevier.es/watermark/ctl_servlet?_f=10&pident_articulo=13190431&pident_usuario=0&pident_revista=62&fichero=62v10n70a13190431pdf001.pdf&ty=4&accion=L&origen=medicine&web=www.medicineonline.es&lan=es

Protocolo de manejo de las cefaleas en los Servicios de Urgencias
http://www.elsevier.es/watermark/ctl_servlet?_f=10&pident_articulo=13190432&pident_usuario=0&pident_revista=62&fichero=62v10n70a13190432pdf001.pdf&ty=5&accion=L&origen=medicine&web=www.medicineonline.es&lan=es

Reintroductions on a Winter’s Eve


DANCE REVIEW

Reintroductions on a Winter’s Eve

Andrea Mohin/The New York Times
Georgina Pazcoguin, left, and Meagan Mann of New York City Ballet soar above Sébastien Marcovici in “The Four Temperaments” on Tuesday night. More Photos »
Life in New York just is more complete when New York City Ballet is in residence and dancing Balanchine. Let me add a few immediate qualifications to that. Like any of the company’s followers, I have my grumbles: I certainly don’t mean to imply that the company should dance nothing but Balanchine; yes, I sometimes see — mainly outside New York — other companies that dance Balanchine as well or better; and there are many other forms of dance and art that I crave. But in its wealth of Balanchine repertory City Ballet has an unmatchable asset, and to renew acquaintance with these ballets can be among the great and regular joys of living in New York.

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Andrea Mohin/The New York Times
Robert Fairchild and Sterling Hyltin performing Balanchine's “Duo Concertant” at City Ballet's opening night on Tuesday. More Photos »
Let nobody take that wealth for granted. The company’s winter season opened on Tuesday with an all-Balanchine program, and over the next six weeks it will dance 27 ballets, 12 of them by Balanchine. (Also on the schedule are works by Jerome RobbinsChristopher Wheeldon and Alexei Ratmansky that I’m keen to see again.) Now compare that to how few other ballets are being danced by any other company in the world over a whole year. This prodigality of choreographic fare has been standard with City Ballet for more than 60 years. Nowhere else will you find it.
To those who wonder if Balanchine can be that great, Tuesday’s quadruple bill was a good corrective. In “Walpurgisnacht Ballet” (1980) the classical choreographer is Romantically inflamed. If ever Balanchine had re-choreographed the full four-act “Swan Lake,” I’d like to imagine he’d have made the scene for the antiheroine Odile like this: voluptuous, intoxicating, with the ballerina leading a female throng whose energies all grow increasingly wild around the bewildered but overwhelmed hero. (“Walpurgisnacht” is choreographed to music for a ballet orgy from Gounod’s opera “Faust.”)
In the “Duo Concertant” duet (1972), Balanchine is the radical modernist who turns Romantic at the end. The ways in which parts of the Stravinsky music are left undanced, the seemingly improvisatory manner in which the dancers start to move; the sudden final shift into a few spotlighted fragments of open-hearted gesture: in no other work does Balanchine seem so deliberately to drop his mastery of classical construction and instead give us something tantalizingly and intentionally incomplete.
“Valse-Fantaisie” from 1967 is strictly classical ballet in vocabulary, heartily Romantic in spirit. Ballerina, male dancer and four-woman corps de ballet are all borne along by the irresistible waltz impulse of Glinka’s music. It feels all too short. Closing the program is “The Four Temperaments” (1946), a Modernist work that embodies just how many contradictory ways Modernism can face at once. It’s a pure-dance theme-and-variations architecture in which a few sparse but subversive and exploratory movement ideas are assembled into a vast and unpredictable whole. It’s a startling new look at the sexes, with women dancing huge, strong and hard, and making fierce demands of men, who are compliant, soft and in some cases conflicted. It’s an expressionist work in which human energies are redefined in terms of the four humors of medieval physiology (Melancholic, Sanguine, Phlegmatic, Choleric). It’s ballet galvanized by drastic impulses that feel very close to the root elements of contraction and release that underlay Martha Graham’s conception of modern dance. And these few notes only scratch its surface.
The musicality of Balanchine’s choreography is often — lazily — spoken of as if there were something inevitable about it, as if the music explained every movement. But it doesn’t take much analysis to see how often Balanchine picks out rhythms that aren’t simply the same as the music’s: frequently they play with expectations, anticipating or answering the music in ways that take you by surprise, arriving on an up just as the music arrives down, and much more. Even in ballets I think I know well, these effects of timing frequently take the breath away as with no other choreographer.
“The Four Temperaments” has been rehearsed to show a few aspects I haven’t seen in recent years, with male chivalry to women wittily reaccentuated. Certainly on Tuesday, the way the men skittered about to serve their women in the three Theme duets had an element (not unwelcome) of enjoyable comedy. The forceful cut-and-thrust that the tall, gorgeous Teresa Reichlen brings to Choleric was the most glorious event of the evening: it epitomized the ways in which Balanchine, and his view of women, went beyond — and remains beyond — all others in ballet.
The other great pleasure on Tuesday was Robert Fairchild in “Duo Concertant.” His first solo, pouncing onto the beat and exploding away from it, had an experimentalist freshness that is another epitome of ideal Balanchine dancing: you couldn’t believe he’d danced it before.

Most of the time Ashley Bouder, in “Valse-Fantaisie,” showed a similar sparkle. The main problem for this terrific virtuoso is her excessive need to project prepared facial expressions. It occurs only when she looks directly out front, as if addressing the rehearsal mirror; an element of calculation seems to enter her upper body. When she’s looking elsewhere — often in this ballet — her dancing comes like birdsong.
Wendy Whelan and Charles Askegard could simply not meet the stylistic demands of “Walpurgisnacht.” Ms. Whelan’s sheer decisiveness and canniness do much to smudge over the cracks in her performance, and Mr. Askegard’s partnering is unsurpassed. But he is stiff, while the adagio and the allegro passages of her role expose problems in her technique. In these conditions, her upper and lower body cease to be precisely coordinated, and her long arms move as if to a different drummer.
As always at City Ballet, there are a number of dancers who, while striking as both beauties and as technicians, remain embryonic, unfulfilled as expressive artists. Sterling Hyltin’s figure has never looked more beautiful than in “Duo Concertant,” and her lightness is heart-catching. If only that lightness were etched more firmly, if only she exerted a new authority.
Andrew Veyette, a short-notice replacement for Joaquin De Luz in “Valse-Fantaisie,” showed a very pleasant warmth and fresh energy, but the elegance of his line is inconsistent. Ana Sophia Scheller, the soloist in “Walpurgisnacht,” is consistently elegant and rhythmically bright; I can’t help wanting her to be more luxurious in one way and more incisive in another. The female corps de ballet in “Walpurgisnacht” glowed with both talent and hope. But the season has only just begun. The story of each of these and many more dancers will unfold in the weeks to come.
The New York City Ballet season continues through Feb. 27 at the David H. Koch Theater, Lincoln Center; (212) 870-5570, nycballet.com
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