Ventilatory acclimatisation is beneficial for high-intensity exercise at altitude in elite cyclists

Aim: The aim of this study was to examine the relationship between ventilatory adaptation and performance during altitude training at 2700?m. Methods: Seven elite cyclists (age: 21.2?±?1.1?yr, body mass: 69.9?±?5.6?kg, height 176.3?±?4.9?cm) participated in this study. A hypoxic ventilatory response (HVR) test and a submaximal exercise test were performed at sea level prior to the training camp and again after 15 d at altitude (ALT15). Ventilation (V_E), end-tidal carbon-dioxide partial pressure (P_ETCO₂) and oxyhaemoglobin saturation via pulse oximetry (SpO₂) were measured at rest and during submaximal cycling at 250?W. A hill climb (HC) performance test was conducted at sea level and after 14 d at altitude (ALT14) using a road of similar length (5.5–6?km) and gradient (4.8–5.3%). Power output was measured using SRM cranks. Average HC power at ALT14 was normalised to sea level power (HC%). Multiple regression was used to identify significant predictors of performance at altitude. Results: At ALT15, there was a significant increase in resting V_E (10.3?±?1.9 vs. 12.2?±?2.4?L·min^?1) and HVR (0.34?±?0.24 vs. 0.71?±?0.49?L·min^?1·%^?1), while P_ETCO₂ (38.4?±?2.3 vs. 32.1?±?3.3?mmHg) and SpO₂ (97.9?±?0.7 vs. 94.0?±?1.7%) were reduced (P?V_E at altitude as significant predictors of HC% (adjusted r²?=?0.913; P?=?0.003). Conclusions: Ventilatory acclimatisation occurred during a 2 wk altitude training camp in elite cyclists and a higher HVR was associated with better performance at altitude, relative to sea level. These results suggest that ventilatory acclimatisation is beneficial for cycling performance at altitude.     

Linking academic knowledge and professional experience in using statistics: a design experiment for business school students

The aim of the empirical study presented in this paper is to explore how students link academic knowledge with workplace experience. I carried out a research study with a group of 36 business school students entering a 3-year masters level apprenticeship programme. In an introductory statistics course, I designed and implemented a four-step learning activity, based on an Exploratory Data Analysis approach and inspired by an authentic workplace situation. I report the findings of qualitative research based on the recorded discussions between students and the reports they wrote at each step in the experience. I found that three different forms of rationality—technical, pragmatic and scientific—led them to shape the problem differently. I observed that they hardly used statistical tools because pragmatic rationality which is linked to their experience as salespersons prevails, although access to a managerial approach suggests the use of more statistical knowledge.     

Innovation in times of financialization: Do future-oriented innovation strategies suffer? Examples from German industry

Shareholder value, short-term strategies, quarterly financial reports, and performance-based remuneration are strong indicators of a financial market-oriented company. It is questionable whether innovativeness and sustainable innovation capabilities can be maintained in times of financialization focused on short-term efficiency instead of free space for creativity and learning. Using the example of established German industrial companies, I examined the extent to which financialization and financial market actors steer innovation strategies and practices. In-depth interviews with companies, cluster managers and banks and reviews of financing data do not reveal a direct influence of financial investors on innovation activities. On the contrary, companies’ managements still have the power to decide how much financial control and standardization they allow for their companies’ innovation practices. The pressure on these German companies to innovate comes from their strong market orientation rather than from financialization.     

The analytical determination of friction for flow through conical converging dies

The effects of friction upon the intermediate and final distorted grids for wire drawing and/or extrusion were analytically studied for an assumed triangular velocity field. An upper-bound solution for the process was used. This solution predicted that the shape of the final and intermediate distorted grids were functions of the process geometry and of friction. Initially, combinations of reduction and semi-cone angle (α) were found for which the triangular velocity field was energetically preferred over an existing spherical velocity field. The analytical final distorted grids were then compared to experimentally obtained final distorted grids to determine the experimental friction. This was done by plotting calibration curves for distortion where friction served as the parameter and by comparing the actual distortion with the family of calibration curves.     

One's reborn every minute: Carter's religious appeal in 1976

An analysis of Jimmy Carter's handling of religion in the 1976 presidential campaign demonstrates that Carter was aware of the potential advantage of emphasizing his religion. In fact, once he became aware of the advantage, he escalated his references to his religion while also attempting to mollify those turned off by his religiosity. The author concludes that Carter's decision to stress his religion was a conscious political decision and that that decision helped Carter win the presidency.     

A computational method for analysis of underwater dolphin kick hydrodynamics in human swimming

We present a new method that combines the use of laser body scans, underwater video footage, software-based animation, and a fully unsteady computational fluid dynamics technique to simulate and examine the hydrodynamics of the dolphin kick. The focus of the current work is to model this particular stroke in all its complexity with minimal ad-hoc assumptions or simplifications. Simulations of one female and one male swimmer (both at about 1.7 m beneath the water surface) at velocities of 0.95 and 1.31 m/s and Strouhal numbers of 1.21 and 1.06 respectively are presented. Vorticity and fluid velocity profiles in the wake are examined in detail for both swimmers. A three-dimensional vortex ring is clearly identified in the wake for one of the cases and a two-dimensional slice through the ring corroborates previous experiments of Miwa et al. (2006). We also find that most of the thrust is produced by the feet and in both cases the down-kick produces much larger thrust than the up-kick.     

Physiological characteristics of successful mountain bikers and professional road cyclists

The aims of this study were to compare the physiological and anthropometric characteristics of successful mountain bikers and professional road cyclists and to re-examine the power-to-weight characteristics of internationally competitive mountain bikers. Internationally competitive cyclists (seven mountain bikers and seven road cyclists) completed the following tests: anthropometric measurements, an incremental cycle ergometer test and a 30 min laboratory time-trial. The mountain bikers were lighter (65.3 - 6.5 vs 74.7 - 3.8 kg, P = 0.01; mean - s ) and leaner than the road cyclists (sum of seven skinfolds: 33.9 - 5.7 vs 44.5 - 10.8 mm, P = 0.04). The mountain bikers produced higher power outputs relative to body mass at maximal exercise (6.3 - 0.5 vs 5.8 - 0.3 W·kg -1 , P = 0.03), at the lactate threshold (5.2 - 0.6 vs 4.7 - 0.3 W·kg -1 , P = 0.048) and during the 30 min time-trial (5.5 - 0.5 vs 4.9 - 0.3 W·kg -1 , P = 0.02). Similarly, peak oxygen uptake relative to body mass was higher in the mountain bikers (78.3 - 4.4 vs 73.0 - 3.4 ml·kg -1 ·min -1 , P = 0.03). The results indicate that high power-to-weight characteristics are important for success in mountain biking. The mountain bikers possessed similar anthropometric and physiological characteristics to previously studied road cycling uphill specialists.     

技术创新网络中核心企业形成的三状态模型研究——基于企业间关系耦合的分析

技术创新网络的扩张与核心企业的成长相互促进,相互决定,形成了复杂的共生演化关系。以知识为基础的企业,必须在各个层次上构建网络,维护多层交互作用,加强与其他企业的合作。从企业间关系耦合的视角,分析了技术创新网络中核心企业的形成过程,提出技术创新网络中各结点企业间的技术合作是一种相互间的知识协同。研究发现,企业间技术交流的过程就是企业间知识匹配——知识流动——知识控制的过程,而技术创新网络中的企业结点也是通过这三种状态,使自身能力得到提升,进而影响到与其他结点的知识协同,并最终成长为核心企业。     

探讨临时支撑卸载分析中的两种方法

目前在工程中，临时支撑卸载过程的分析和模拟主要有两种方法．利用这两种方法分别建立临时支撑卸载的有限元模型并在ANSYS中对这两个模型的卸载过程进行模拟和分析，从理论上和有限元分析结果上对这两种方法进行了探讨．