A cooperative model of multiple primary and secondary users coexisting cognitive network is presented. In this model, the control center is aware of all the users＇ locations in order to allocate the nearest secondary...A cooperative model of multiple primary and secondary users coexisting cognitive network is presented. In this model, the control center is aware of all the users＇ locations in order to allocate the nearest secondary user to the primary user. The control center is aware of the information of the unused spectral resources in terms of the feedback of the sensing results from the secondary users. It allocates idle frequency bands among the secondary users. The primary user accesses the base station （BS） in orthogonal subchannels, and it cooperatively transmits packets with the secondary user and exploits the free band assigned by the control center to amplify-and-forward what it receives immediately. Under this scenario, the outage probability of the cooperative transmission pair of the primary and secondary transmitters is derived. The numerical simulation of the outage probabilities as a function of primary transmission probability ps, power allocation ratio ξ between the primary and secondary users, and the numbers of the primary and secondary users are given respectively. The results show that the optimal system performance is achieved under the conditions of ξ=0.5 and the numbers of the primary and the secondary users being equal.展开更多
AIM： TO evaluate the effectiveness and safety of capsule endoscopy （CE） in patients with recurrent subacute small bowel obstruction.METHODS： The study was a retrospective analysis of 31 patients referred to hospit...AIM： TO evaluate the effectiveness and safety of capsule endoscopy （CE） in patients with recurrent subacute small bowel obstruction.METHODS： The study was a retrospective analysis of 31 patients referred to hospital from January 2003 to August 2008 for the investigation of subacute small bowel obstruction, who underwent CE. The patients were aged 9-81 years, and all of them had undergone gastroscopy and colonoscopy previously. Some of them received abdominal computed tomography or small bowel follow-through.RESULTS： CE made a definitive diagnosis in 12 （38.7%） of 31 cases： four Crohn＇s disease （CD）, two carcinomas, one intestinal tuberculosis, one ischemic enteritis, one abdominal cocoon, one duplication of the intestine,one diverticulum and one ileal polypoid tumor. Capsule retention occurred in three （9.7%） of 31 patients, and was caused by CD （2） or tumor （1）. Two with retained capsules were retrieved at surgery, and the other one of the capsules was spontaneously passed the stricture by medical treatment in 6 too. No case had an acute small bowel obstruction caused by performance of CE.CONCLUSION： CE provided safe and effective visualization to identify the etiology of a subacute small bowel obstruction, especially in patients with suspected intestinal tumors or CD, which are not identified by routine examinations.展开更多
Capsule endoscopy (CE) is a novel technology that facilitates highly effective and noninvasive imaging of the small bowel. Although its effi cacy in the evaluation of obscure gastrointestinal bleeding (OGIB) has been ...Capsule endoscopy (CE) is a novel technology that facilitates highly effective and noninvasive imaging of the small bowel. Although its effi cacy in the evaluation of obscure gastrointestinal bleeding (OGIB) has been proven in several trials, data on uses of CE in different small bowel diseases are rapidly accumulating in the literature, and it has been found to be superior to alternative diagnostic tools in a range of such diseases. Based on literature evidence, CE is recommended as a first-line investigation for OGIB after negative bi-directional endoscopy. CE has gained an important role in the diagnosis and follow-up of Crohn's disease and celiac disease and in the surveillance of small bowel tumors and polyps in selected patients. Capsule retention is the major complication, with a frequency of 1%-2%. The purpose of this review was to discuss the procedure, indications, contraindications and adverse effects associated with CE. We also review and share our five-year experience with CE in various small bowel diseases. The recently developed balloon-assisted enteroscopies have both diagnostic and therapeutic capability. At the present time, CE and balloon-assisted enteroscopies are complementary techniques in the diagnosis and management of small bowel diseases.展开更多
AIM:To review the literature on capsule endoscopy(CE) for detecting esophageal varices using conventional esophagogas troduodenoscopy(EGD)as the standard. METHODS:A strict literature search of studies comparing the yi...AIM:To review the literature on capsule endoscopy(CE) for detecting esophageal varices using conventional esophagogas troduodenoscopy(EGD)as the standard. METHODS:A strict literature search of studies comparing the yield of CE and EGD in patients diagnosed or suspected as having esophageal varices was conducted by both computer search and manual search.Data were extracted to estimate the pooled diagnostic sensitivity and specificity. RESULTS:There were seven studies appropriate for meta-analysis in our study,involving 446 patients. The pooled sensitivity and specificity of CE for detecting esophageal varices were 85.8%and 80.5%, respectively.In subgroup analysis,the pooled sensitivity and specificity were 82.7%and 54.8%in screened patients,and 87.3%and 84.7%in the screened/ patients under surveillance,respectively. CONCLUSION:CE appears to have acceptable sensitivity and specificity in detecting esophageal varices.However,data are insufficient to determine the accurate diagnostic value of CE in the screen/ surveillance of patients alone.展开更多
Motor vehicle accidents (MVAs) are serious social issues worldwide and driver illness is an important cause of MVAs. Minimal hepatic encephalopathy (MHE) is a com- plex cognitive dysfunction with attention deficit, wh...Motor vehicle accidents (MVAs) are serious social issues worldwide and driver illness is an important cause of MVAs. Minimal hepatic encephalopathy (MHE) is a com- plex cognitive dysfunction with attention deficit, which frequently occurs in cirrhotic patients independent of severity of liver disease. Although MHE is known as a risk factor for MVAs, the impact of diagnosis and treatment of MHE on MVA-related societal costs is largely unknown. Recently, Bajaj et al demonstrated valuable findings that the diagnosis of MHE by rapid screening using the inhibitory control test (ICT), and subsequent treatment with lactulose could substantially reduce the societal costs by preventing MVAs. Besides the ICT and lactulose, there are various diagnostic tools and therapeutic strategies for MHE. In this commentary, we discussed a current issue of diagnostic tools for MHE, including neuropsychological tests. We also discussed the advantages of the other therapeutic strategies for MHE, such as intake of a regular breakfast and coffee, and supplementation with zinc and branched chain amino acids, on the MVA-related societal costs.展开更多
The development of cognitive competences for police officers and other officers of the uniformed services is crucial The Police Academy in Szczytno （Poland） developed--as part of a research and development project ...The development of cognitive competences for police officers and other officers of the uniformed services is crucial The Police Academy in Szczytno （Poland） developed--as part of a research and development project （2013-2015）---an innovative diagnostic system for training that allows automated assessment of the current fitness level of cognitive functions and their online training. The system consists of three interconnected modules： diagnostic module, training module, and knowledge base. It is a fully functional online platform. Various forms of cognitive training in the form of games have been proposed. The system includes a component in the form of a psychophysiological recorder, which is intended for the training of coping with stress. The innovativeness of this diagnostic training system involves the use of information systems to stimulate the cognitive competence of officers by designing exercises in the form of computer games and to permit to verify their current mental shapes. It is assumed that this solution will develop the personal skills of officers and positively affect their operational readiness. Extending the area of application of this diagnostic training module by other functionalities can contribute to improving the effectiveness and safety of work, especially in occupational groups performing tasks requiring special cognitive and psychomotor predispositions.展开更多
基金The National Natural Science Foundation of China (No.60972026)the Natural Science Foundation of Jiangsu Province (No.BK2008289)Specialized Research Fund for the Doctoral Program ofHigher Education (No.20090092110009)
文摘A cooperative model of multiple primary and secondary users coexisting cognitive network is presented. In this model, the control center is aware of all the users＇ locations in order to allocate the nearest secondary user to the primary user. The control center is aware of the information of the unused spectral resources in terms of the feedback of the sensing results from the secondary users. It allocates idle frequency bands among the secondary users. The primary user accesses the base station （BS） in orthogonal subchannels, and it cooperatively transmits packets with the secondary user and exploits the free band assigned by the control center to amplify-and-forward what it receives immediately. Under this scenario, the outage probability of the cooperative transmission pair of the primary and secondary transmitters is derived. The numerical simulation of the outage probabilities as a function of primary transmission probability ps, power allocation ratio ξ between the primary and secondary users, and the numbers of the primary and secondary users are given respectively. The results show that the optimal system performance is achieved under the conditions of ξ=0.5 and the numbers of the primary and the secondary users being equal.
文摘AIM： TO evaluate the effectiveness and safety of capsule endoscopy （CE） in patients with recurrent subacute small bowel obstruction.METHODS： The study was a retrospective analysis of 31 patients referred to hospital from January 2003 to August 2008 for the investigation of subacute small bowel obstruction, who underwent CE. The patients were aged 9-81 years, and all of them had undergone gastroscopy and colonoscopy previously. Some of them received abdominal computed tomography or small bowel follow-through.RESULTS： CE made a definitive diagnosis in 12 （38.7%） of 31 cases： four Crohn＇s disease （CD）, two carcinomas, one intestinal tuberculosis, one ischemic enteritis, one abdominal cocoon, one duplication of the intestine,one diverticulum and one ileal polypoid tumor. Capsule retention occurred in three （9.7%） of 31 patients, and was caused by CD （2） or tumor （1）. Two with retained capsules were retrieved at surgery, and the other one of the capsules was spontaneously passed the stricture by medical treatment in 6 too. No case had an acute small bowel obstruction caused by performance of CE.CONCLUSION： CE provided safe and effective visualization to identify the etiology of a subacute small bowel obstruction, especially in patients with suspected intestinal tumors or CD, which are not identified by routine examinations.
文摘Capsule endoscopy (CE) is a novel technology that facilitates highly effective and noninvasive imaging of the small bowel. Although its effi cacy in the evaluation of obscure gastrointestinal bleeding (OGIB) has been proven in several trials, data on uses of CE in different small bowel diseases are rapidly accumulating in the literature, and it has been found to be superior to alternative diagnostic tools in a range of such diseases. Based on literature evidence, CE is recommended as a first-line investigation for OGIB after negative bi-directional endoscopy. CE has gained an important role in the diagnosis and follow-up of Crohn's disease and celiac disease and in the surveillance of small bowel tumors and polyps in selected patients. Capsule retention is the major complication, with a frequency of 1%-2%. The purpose of this review was to discuss the procedure, indications, contraindications and adverse effects associated with CE. We also review and share our five-year experience with CE in various small bowel diseases. The recently developed balloon-assisted enteroscopies have both diagnostic and therapeutic capability. At the present time, CE and balloon-assisted enteroscopies are complementary techniques in the diagnosis and management of small bowel diseases.
基金Supported by Shanghai Educational Development Foundation Shanghai Chenguang Project,No.2007CG49
文摘AIM:To review the literature on capsule endoscopy(CE) for detecting esophageal varices using conventional esophagogas troduodenoscopy(EGD)as the standard. METHODS:A strict literature search of studies comparing the yield of CE and EGD in patients diagnosed or suspected as having esophageal varices was conducted by both computer search and manual search.Data were extracted to estimate the pooled diagnostic sensitivity and specificity. RESULTS:There were seven studies appropriate for meta-analysis in our study,involving 446 patients. The pooled sensitivity and specificity of CE for detecting esophageal varices were 85.8%and 80.5%, respectively.In subgroup analysis,the pooled sensitivity and specificity were 82.7%and 54.8%in screened patients,and 87.3%and 84.7%in the screened/ patients under surveillance,respectively. CONCLUSION:CE appears to have acceptable sensitivity and specificity in detecting esophageal varices.However,data are insufficient to determine the accurate diagnostic value of CE in the screen/ surveillance of patients alone.
文摘Motor vehicle accidents (MVAs) are serious social issues worldwide and driver illness is an important cause of MVAs. Minimal hepatic encephalopathy (MHE) is a com- plex cognitive dysfunction with attention deficit, which frequently occurs in cirrhotic patients independent of severity of liver disease. Although MHE is known as a risk factor for MVAs, the impact of diagnosis and treatment of MHE on MVA-related societal costs is largely unknown. Recently, Bajaj et al demonstrated valuable findings that the diagnosis of MHE by rapid screening using the inhibitory control test (ICT), and subsequent treatment with lactulose could substantially reduce the societal costs by preventing MVAs. Besides the ICT and lactulose, there are various diagnostic tools and therapeutic strategies for MHE. In this commentary, we discussed a current issue of diagnostic tools for MHE, including neuropsychological tests. We also discussed the advantages of the other therapeutic strategies for MHE, such as intake of a regular breakfast and coffee, and supplementation with zinc and branched chain amino acids, on the MVA-related societal costs.
文摘The development of cognitive competences for police officers and other officers of the uniformed services is crucial The Police Academy in Szczytno （Poland） developed--as part of a research and development project （2013-2015）---an innovative diagnostic system for training that allows automated assessment of the current fitness level of cognitive functions and their online training. The system consists of three interconnected modules： diagnostic module, training module, and knowledge base. It is a fully functional online platform. Various forms of cognitive training in the form of games have been proposed. The system includes a component in the form of a psychophysiological recorder, which is intended for the training of coping with stress. The innovativeness of this diagnostic training system involves the use of information systems to stimulate the cognitive competence of officers by designing exercises in the form of computer games and to permit to verify their current mental shapes. It is assumed that this solution will develop the personal skills of officers and positively affect their operational readiness. Extending the area of application of this diagnostic training module by other functionalities can contribute to improving the effectiveness and safety of work, especially in occupational groups performing tasks requiring special cognitive and psychomotor predispositions.
