Chronic Groin Pain (Inguinodynia) following inguinal hernia repair is a significant,though under-reported problem. Mild pain lasting for a few days is common following mesh inguinal hernia repair. However,moderate to ...Chronic Groin Pain (Inguinodynia) following inguinal hernia repair is a significant,though under-reported problem. Mild pain lasting for a few days is common following mesh inguinal hernia repair. However,moderate to severe pain persisting more than 3 mo after inguinal herniorrhaphy should be considered as pathological. The major reasons for chronic groin pain have been identified as neuropathic cause due to inguinal nerve(s) damage or non-neuropathic cause due to mesh or other related factors. The symptom complex of chronic groin pain varies from a dull ache to sharp shooting pain along the distribution of inguinal nerves. Thorough history and meticulous clinical examination should be performed to identify the exact cause of chronic groin pain,as there is no single test to confirm the aetiology behind the pain or to point out the exact nerve involved. Various studies have been performed to look at the difference in chronic groin pain rates with the use of mesh vs non-mesh repair,use of heavyweight vs lightweight mesh and mesh fixation with sutures vs glue. Though there is no convincing evidence favouring one over the other,lightweight meshes are generally preferred because of their lesser foreign body reaction and better tolerance by the patients. Identification of all three nerves has been shown to be an important factor in reducing chronic groin pain,though there are no well conducted randomised studies to recommend the benefits of nerve excision vs preservation. Both nonsurgical and surgical options have been tried for chronic groin pain,with their consequent risks of analgesic sideeffects,recurrent pain,recurrent hernia and significant sensory loss. By far the best treatment for chronic groin pain is to avoid bestowing this on the patient by careful intra-operative handling of inguinal structures and better patient counselling pre-and post-herniorraphy.展开更多
This paper compares the stock return distribution models of mixture normal distribution, mixed diffusion-jump and GARCH models based on the data of Chinese stock market. The Schwarz criterion is also used. We find all...This paper compares the stock return distribution models of mixture normal distribution, mixed diffusion-jump and GARCH models based on the data of Chinese stock market. The Schwarz criterion is also used. We find all these models can capture the features of stock returns partly. EGARCH model is the best fitting to daily return and stable during different period. When the weekly and monthly returns are tested, the differences of the models' fitness become unobvious and unstable.展开更多
Price volatility in stock market brings potential profile positions to the traders. How to predict the direction of the stock market or stock price becomes the primary job for traders' trading model. We are looking f...Price volatility in stock market brings potential profile positions to the traders. How to predict the direction of the stock market or stock price becomes the primary job for traders' trading model. We are looking for the direction of the market in a given timeframe. High-frequency traders will consider the potential profile-out position in millisecond level. Long-term holder will look into month time scale. For most of average traders, the ideal timeframe will be on daily base. In this paper, for a non-news trading day, the author will introduce statistics method to predict the stock prices and bid-ask spread for day trading.展开更多
文摘Chronic Groin Pain (Inguinodynia) following inguinal hernia repair is a significant,though under-reported problem. Mild pain lasting for a few days is common following mesh inguinal hernia repair. However,moderate to severe pain persisting more than 3 mo after inguinal herniorrhaphy should be considered as pathological. The major reasons for chronic groin pain have been identified as neuropathic cause due to inguinal nerve(s) damage or non-neuropathic cause due to mesh or other related factors. The symptom complex of chronic groin pain varies from a dull ache to sharp shooting pain along the distribution of inguinal nerves. Thorough history and meticulous clinical examination should be performed to identify the exact cause of chronic groin pain,as there is no single test to confirm the aetiology behind the pain or to point out the exact nerve involved. Various studies have been performed to look at the difference in chronic groin pain rates with the use of mesh vs non-mesh repair,use of heavyweight vs lightweight mesh and mesh fixation with sutures vs glue. Though there is no convincing evidence favouring one over the other,lightweight meshes are generally preferred because of their lesser foreign body reaction and better tolerance by the patients. Identification of all three nerves has been shown to be an important factor in reducing chronic groin pain,though there are no well conducted randomised studies to recommend the benefits of nerve excision vs preservation. Both nonsurgical and surgical options have been tried for chronic groin pain,with their consequent risks of analgesic sideeffects,recurrent pain,recurrent hernia and significant sensory loss. By far the best treatment for chronic groin pain is to avoid bestowing this on the patient by careful intra-operative handling of inguinal structures and better patient counselling pre-and post-herniorraphy.
文摘This paper compares the stock return distribution models of mixture normal distribution, mixed diffusion-jump and GARCH models based on the data of Chinese stock market. The Schwarz criterion is also used. We find all these models can capture the features of stock returns partly. EGARCH model is the best fitting to daily return and stable during different period. When the weekly and monthly returns are tested, the differences of the models' fitness become unobvious and unstable.
文摘Price volatility in stock market brings potential profile positions to the traders. How to predict the direction of the stock market or stock price becomes the primary job for traders' trading model. We are looking for the direction of the market in a given timeframe. High-frequency traders will consider the potential profile-out position in millisecond level. Long-term holder will look into month time scale. For most of average traders, the ideal timeframe will be on daily base. In this paper, for a non-news trading day, the author will introduce statistics method to predict the stock prices and bid-ask spread for day trading.