突发！全线下跌！

Market Overview - A-shares experienced a significant drop on July 31, with the Shanghai Composite Index falling over 1% and closing at 3573.21 points, while the Shenzhen Component Index and ChiNext Index declined nearly 2% [1][2] - The total trading volume in the Shanghai and Shenzhen markets reached approximately 1.96 trillion yuan, an increase of over 90 billion yuan compared to the previous day [1][2] Sector Performance - The overall market showed weakness, with nearly 4300 stocks declining. Key sectors such as coal, steel, oil, and non-ferrous metals saw collective pullbacks, while brokerage, insurance, liquor, and banking sectors also fell [2] - Conversely, the information security sector surged, with stocks like Digital Certification and South Star shares hitting the daily limit, and others like Yonyou Network and Yongxin Zhicheng rising over 8% [2][4] - The assisted reproduction sector was active, with stocks like Anke Bio, Gongtong Pharmaceutical, and Lideman reaching the daily limit of 20% [11][12] Information Security Sector - The information security concept saw a strong rally, with stocks such as *ST Guandao and Digital Certification hitting their daily limits, and others like Yonyou Network and Deepin Technology also performing well [4][5] - The National Internet Information Office recently addressed Nvidia regarding security risks associated with its H20 computing chips, which may impact the information security landscape [6] AI Industry Chain - Stocks related to the AI industry chain, including liquid-cooled servers and CPO concepts, experienced significant gains, with Fangsheng Co. rising over 15% and Dingtong Technology increasing over 10% [8][9] - Domestic AI models, represented by the DeepSeek series, are now comparable to leading overseas models, with advancements in AI chip manufacturing by companies like Huawei and Haiguang Information [10] Assisted Reproductive Technology - The recent announcement of a child-rearing subsidy policy is expected to stimulate consumption in the mother and baby-related sectors, with a budget of approximately 90 billion yuan allocated for this initiative [13] - The policy is anticipated to boost birth rates and positively impact industries such as assisted reproduction, genetic testing, and childcare services [13]