Relatively High Bone Mineral Density in Chinese Adolescent Dancers Despite Lower Energy Intake and Menstrual Disorder

Objective The effect of dietary restriction, intense exercise and menstrual dysfunction on bone mineral density remains controversial. The aim of this study was to assess the skeletal health status and relationship between bone mineral density and nutrient intake, menstrual status, estrogen level and other factos in Chinese adolescent dancers. Methods Sixty dancers and 77 healthy controls underwent measurements of bone density, body composition, and estrogen level. Nutrient intake, menstrual status and physical activity were assessed with questionnaires. The correlation between these factors were analyzed. Results The dancers under study had a significantly lean body mass index （18.3±1.4 kg/m^2 vs. 21.7±3.1 kg/m^2）, lower percentage of body fat （0.25±0.05 vs. 0.34±0.04） and later age at menarche （14.0±0.9 y vs. 13.0±1.3 y）, and the estrogen level, daily calorie and fat intake in them were also lower than in the controls. All the dancers undertook intensive physical activity every day and up to 69% of them suffered from irregular menarche. Yet they had relatively high BMD and BMC of the total body and legs than the controls after adjusting for BM1 and age. Site-specific BMD was positively correlated to BMI, body composition and training hours per week and negatively correlated to the age at menarche and menstrual frequency. Conclusions The relatively high BMD and BMC of the dancers at the total body and legs were probably caused by high levels of weight-bearing physical activity. To ameliorate disordered eating, especially low energy intake might be helpful to prevent the Triad and to improve the bone health in adolescent dancers.

Injuries Requiring Surgery in Folk Dancers： A Retrospective Cohort Study of 9 Years

Background： In this study, we examined professional folk dancer injuries which required surgery and if there are any associated factors like age, gender, dexterity, dance style and to evaluate the return to their full capacity. Materials and Methods： Seventy five members of the Fire of Anatolia dance group （mean age： 26.8 ± 5.2; 18-38 years） performers were evaluated. The dancers suffered 14 orthopedic injuries requiring surgery （3 meniscus tears, 2 anterior cruciate ligament tears one of which is with posterolateral corner tear, 1 posterior cruciate ligament tear, 1 patellar dislocation, 1 scaphoid fracture, 1 extensor tendon cut in hand, 1 infrapatellar bursitis, 2 Hoffa’s fat pad syndromes, 2 symptomatic medial plicaes） during a nine-year period. Follow-up time was 51 ± 41.9 （29.5-92） months. Results： Following surgeries, the dancers could restart rehearsals in 12.7 ± 9 （range： 4 to 36） weeks and perform live on the stage in 16.2 ± 12.2 （range： 5 to 52） weeks on average. Conclusion： Males were 8.64 times more likely to suffer an injury requiring surgery compared to the females （p = 0.003） and twelve （85.7%） of these injuries were lower extremity injuries and were all located in the knee in Anatolian folk dancers.

A Family of Dancers

AS the last strains of music from Swan Lake faded, ballerina Yu Chuanya returned to stage in joburg Theater from the wings to take a bow. She was joined by other dancers from China, South Africa, Cuba and the United States, It was April 17, the open- ing night of the current season, and the first joint performance was greeted with rapturous applause, The collaboration between the Liaoning Ballet and Joburg Ballet companies in a new production of the classic Swan Lake was the first of its kind. Their 21 performances in South Africa gave audiences the first opportunity to watch such an eclectic group of danc- ers on stage in a single production,

Correlation of Serum Leptin Level with Bone Mineral Density and Bone Turnover Markers in Chinese Adolescent Dancers

Objective To investigate plasma leptin concentrations in adolescent female dancers and to determine whether leptin has some effects on their bone mineral density （BMD） and bone turnover markers. Methods Sixty dancers aged 15-17 years and 77 healthy controls were enrolled in the study. Bone mineral density （BMD） and body composition were detected by dual energy X-ray absorptiometry. Serum leptin concentrations were measured by radioimmunoassay （RIA）. Two bone turnover markers, bone-specific alkaline phosphatase （BAP） and tartrate-resistant acid phosphatase（TRACP）, were determined by ELISA. Results The dancers had a lower fat mass and a lower leptin level than the controls, while they had a relatively higher BMD of the total body and legs after adjustment for BMI and age. The levels of bone resorption and formation of markers were higher in the dancers than in the controls. Leptin was positively correlated with BMI, body weight, fat mass, and percentage of body fat. In dancers, Leptin was positively correlated with the BMD of the total body and the left leg. However, after adjustment for BMI, no correlation of serum leptin concentrations with BMD values was found in either dancers or controls. Nor correlation was found between leptin and bone turnover markers after adjustment for BMI. Conelusion The leptin profile is different between the controls and the dancers with a lower BMI and a lower fat mass. Circulating plasma leptin level depends on BMI and is not a direct determinant of BMD in Chinese adolescent dancers.

Bone Quality in Female Ballet Dancers: A Possible Determinant of Bone Health

Hypotheses:Values of serum markers related to bone quality are abnormal in young female ballet dancers. Methods: In 13 elite Japanese female ballet dancers (average age, 22 years), markers related to bone quality were investigated. These included: serum homocystein (HC), a marker of increased oxidative stress;pentosidine (Pent), a marker of glycation- or oxidation-induced non-enzymatic cross-links;markers of bone metabolism (bone alkaline phosphatase, BAP;tartrate-resistant acid phosphatase 5b, TRAP5b) and bone mineral density (BMD). It was determined whether there is a relationship between bone quality markers’ levels are related to amenorrhea and/or fatigue fractures. Results: Two dancers had fatigue fractures and 3 had a history of secondary amenorrhea. The average BMD was 1.305 ± 0.12 (g/cm2), in all these cases the Z-score was higher than -1.0. Although the serum levels of BAP, TRAP5b, and HC were normal in all examined dancers, in 2 out of 3 dancers with a history of secondary amenorrhea, pentosidine serum levels were increased. No relationship between bone quality markers’ levels and fatigue fractures was found. Conclusion: Latent deterioration of bone quality may occur in female athletes with secondary amenorrhea and otherwise normal BMD and calcium metabolism markers.

关于锥内正映射不动点指标的一个猜想

对E .N .Dancer提出的一个关于锥内正映射不动点指标的猜想进行了讨论 .首先利用泛函对锥的几何性质进行刻画 ,然后在锥的内点非空的条件下 ,利用算子扰动方法证明了这一猜想 。

带非线性边界条件的二阶差分方程正解的全局结构

用分歧理论考察二阶离散边值问题{-Δ[p(k-1)Δu(k-1)]+q(k)u(k)=λa(k)f(u(k)),k∈[1,N]_Z,g_1(λ,u(0),Δu(0))=0,g_2(λ,u(N+1),Δu(N))=0正解的全局结构,得到了该问题正解存在的最优充分条件.其中:λ>0是参数;[1,N]Z={1,2,…,N};p:[0,N+1]Z→+,q,a:[1,N]Z→R^+且对k∈[1,N]Z,a(k)>0;g_1∈C(R^+×R^+×R^+,R^+);g_2∈C(R^+×R^+×(-∞,0],R^+);f∈C(R^+,R~^+).

一类三阶非线性常微分方程边值问题正解的存在性

本文研究了一类三阶非线性常微分方程边值问题■正解的存在性,其中f∈C([0,1]×R,R)且当|u′|→0时,f(t,u′)=au′+o(|u′|);当|u′|→∞时f(t,u′)=bu′+o(|u′|),a,b∈(0,+∞).主要结果的证明基于Dancer全局分歧定理.

Web Tension Regulation of Multispan Roll-to-Roll System using Integrated Active Dancer and Load Cells for Printed Electronics Applications

The mass production of primed electronics can be achieved by roll-to-roll（R2R） printing system, so highly accurate web tension is required that can minimize the register error and keep the thickness and roughness of printed devices in limits. The web tension of a R2R system is regulated by the use of integrated load cells and active dancer system for printed electronics applications using decentralized multi-input-single-output（MISO） regularized variable learning rate backpropagation artificial neural networks. The active dancer system is used before printing system to reduce disturbances in the web tension of process span. The classical PID control result in tension spikes with the change in roll diameter of winder and unwinder rolls. The presence of dancer in R2R system shows that improved web tension control in printing span and the web tension can be enhanced from 3.75 N to 4.75 N. The overshoot of system is less than ±2.5 N and steady state error is within ± 1 N where load cells have a signal noise of ±0.7 N. The integration of load cells and active dancer with self-adapting neural network control provide a solution to the web tension control of multispan roll-to-roll system.

残忍的“梦幻” 无奈的温情——解读《黑暗中的舞者》Dancer in the Dark

美国,移民的梦幻之都,各国都有人希望可以在那里找到黄金,完成一夜暴富的美国梦。可是真正能够实现这个美好梦想的又有几个人呢?现在几乎所有的人都已经知道在这样的梦幻之都找到黄金的希望有多么渺茫,可是依然对这个国度趋之若鹜。母爱,世界上最无私的感情,母亲可以为了自己的孩子付出一切,甚至生命;但是在这样残忍的现实之中,母亲为了保护自己的孩子,只能不择手段。这样的母爱,到底是伟大无私,还是略带残忍的无奈?

带参数的一阶周期边值问题正解的全局结构

本文运用Dancer全局分歧定理研究了带参数的一阶周期边值问题{u′+a(t)u=rf(u),t∈(0,1),u(0)=u(1)正解的全局结构,获得了正解存在的最优区间.其中r为正参数,f∈C(R,R),a∈C([0,1],[0,∞)),且a(t)在[0,1]的任意子区间内不恒为0.

Chinese Folk Dance -Taking Uighur Dance as an Example

Chinese folk dance has a long history and is quite abundant. It is an indispensable source of Chinese classical dance, court dance and professional dance creation. Chinese folk dances are characterized by unpretentiousness, diverse forms, rich content, and vivid images. But these require professional dancers to express through professional training. Even amateur dances need to be completed through well-trained and emotionally full actors.⑴ In the process of training, in addition to the necessary basic skills and other physical training, we also need to train the demeanor. We often say that the eyes are the windows of the soul, and the folk dance is more about expressing a feeling to the audience. If the dancer don't have a good performance and face expression, he or she can't express the dance work at all. Therefore, this article takes the training of national folk dance as the starting point, combining technical training, stage perfonnance, professional dancers and amateur dancers, taking the Uygur as an example.

IR委任Oleg Khaykin为新一任总裁兼CEO

全球功率半导体和管理方案领导厂商——国际整流器公司宣布委任Oleg Khaykin先生为新一任总裁兼CEO。Khaykin先生将于2008年3月1日正式上任,并接替由2007年8月30日起出任代理CEO的Donald Dancer。Dance冼生将继续服务公司,支持Khaykin先生担任新职,也会积极确保公司相关工作的顺利过渡。

Bai Ji,a Young Dancer

Bai Ji is a second-class performer,a member of the Chinese Dancers’Association,vice-president of Tibet Dancers’ Association,a member of the China National Youth Federation,and an"excellent daughter of the frontier."Bai Ji graduated from the Beijing Dance Institute with excellent marks in 1982.She has not only a good

十二生肖做伯爵

伯爵发布了Dancer十二生肖系列手表。古老而深邃的中国文化元素进入瑞士钟表品牌的产品不少见,但是推出一套共12款的手表系列则较为罕见。生肖系列的表壳直径有38毫米,比Dancer系列略大,这是为了更好地表现题材。

Who Is the Dancer

Dancer--the dancer of the acrobatic circle! Dancer--the dancer of the whole world!The year 2006 was destined to be remembered in the history of Fujian Acrobatic Troupe. In 2006, when all the members of the troupe were preparing for the Troupe Founding Semi centen- nial Celebration day and night,

软件插件技巧集锦（二）

领略真人美女动感舞蹈