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1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Biology · 术语表

什么是 Muscle？

又称： contract

Definition 17.6 Primary & Middle School Biology · 第 17 章 — Bones and Muscles

A muscle is a fleshy motor attached to the bones. A muscle can contract — shorten and thicken — and in contracting it pulls the bone it is attached to. Muscles only pull; no muscle can push.

Bending the elbow: the front muscle of the pair bulges as it shortens and pulls the forearm up, while its partner behind rests. To straighten, the two swap roles.

示例

Example 17.8 (Feel the pair at work)

Grip your upper arm with the other hand and slowly bend the elbow: the muscle in front swells and hardens — it is contracting. Now straighten the arm: the front softens, and behind the arm its partner tightens instead. You have just felt Proposition 17.7 happen.

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