Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast e...Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security.展开更多
BACKGROUND Chronic hepatitis B virus(HBV)infection remains a major global public health problem.Chronic hepatitis B(CHB)patients can be divided into treatment indication and non-treatment indication individuals accord...BACKGROUND Chronic hepatitis B virus(HBV)infection remains a major global public health problem.Chronic hepatitis B(CHB)patients can be divided into treatment indication and non-treatment indication individuals according to alanine transaminase(ALT),HBV DNA,serum hepatitis B e antigen status,disease status[liver cirrhosis,hepatocellular carcinoma(HCC),or liver failure],liver necroinflammation or fibrosis,patients’age,and family history of HCC or cirrhosis.For example,normal ALT patients in‘immune-tolerant’phase with HBV DNA higher than 10^(7)or 2×10^(7)IU/mL,and those in‘inactive-carrier’phase with HBV DNA lower than 2×10^(3)IU/mL do not require antiviral therapy.However,is it reasonable to set the defined values of HBV DNA as the fundamental basis to estimate the disease state and to determine whether to start treatment?In fact,we should pay more attention to those who do not match the treatment indications(grayzone patients both in the indeterminate phase and in the‘inactive-carrier’phase).AIM To analyze the correlation of HBV DNA level and liver histopathological severity,and to explore the significance of HBV DNA for CHB with normal ALT.METHODS From January 2017 to December 2021,a retrospective cross-sectional set of 1299 patients with chronic HBV infection(HBV DNA>30 IU/mL)who underwent liver biopsy from four hospitals,including 634 with ALT less than 40 U/L.None of the patients had received anti-HBV treatment.The degrees of liver necroinflammatory activity and liver fibrosis were evaluated according to the Metavir system.On the basis of the HBV DNA level,patients were divided into two groups:Low/moderate replication group,HBV DNA≤10^(7)IU/mL[7.00 Log IU/mL,the European Association for the Study of the Liver(EASL)guidelines]or≤2×10^(7)IU/mL[7.30 Log IU/mL,the Chinese Medical Association(CMA)guidelines];high replication group,HBV DNA>10^(7)IU/mL or>2×10^(7)IU/mL.Relevant factors(demographic characteristics,laboratory parameters and noninvasive models)for liver histopathological severity were analyzed by univariate analysis,logistics analysis and propensity score-matched analysis.RESULTS At entry,there were 21.45%,24.29%,and 30.28%of the patients had liver histopathological severities with≥A2,≥F2,and≥A2 or/and≥F2,respectively.HBV DNA level(negative correlation)and noninvasive model liver fibrosis 5 value(positive correlation)were independent risk factors for liver histopathological severities(liver necroinflammation,liver fibrosis,and treatment indication).The AUROCs of the prediction probabilities(PRE_)of the models mentioned above(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.814(95%CI:0.770-0.859),0.824(95%CI:0.785-0.863),and 0.799(95%CI:0.760-0.838),respectively.HBV DNA level(negative correlation)was still an independent risk factor when diagnostic models were excluded,the P values(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.011,0.000,and 0.000,respectively.For the propensity score-matched pairs,whether based on EASL guidelines or CMA guidelines,the group with significant liver histology damage(≥A2 or/and≥F2)showed much lower HBV DNA level than the group with non-significant liver histology damage(<A2 and<F2).Patients in the moderate replication group(with indeterminate phase)had the most serious liver disease pathologically and hematologically,followed by patients in the low replication group(with‘inactive-carrier’phase)and then the high replication group(with‘immune-tolerant’phase).CONCLUSION HBV DNA level is a negative risk factor for liver disease progression.The phase definition of CHB may be revised by whether the level of HBV DNA exceeds the detection low limit value.Patients who are in the indeterminate phase or‘inactive carriers’should receive antiviral therapy.展开更多
The field of plastic surgery has developed rapidly in the last couple of decades in Hong Kong and Shanghai,China.Both cities have their own educational system for training plastic surgeons.Their training programs diff...The field of plastic surgery has developed rapidly in the last couple of decades in Hong Kong and Shanghai,China.Both cities have their own educational system for training plastic surgeons.Their training programs differ in many ways,including the surgical exposure of undergraduate studies,the structure,curriculum,and operative requirements of residency training.In general,Hong Kong has a single pathway of residency training with more early clinical exposure in an undergraduate study.On the contrary,Shanghai has multiple pathways of residency training that are heavily emphasized in academic research.Both Hong Kong and Shanghai should complement each other to modify their plastic surgery training programs that will eventually benefit the field of plastic surgery education。展开更多
The saturate,aromatics,resin and asphaltene components of paraffin-base(PB)and naphthenic-base(HB)crude oil are separated by chromatographic column.The acidic components of crude oil are extracted by compounded polar ...The saturate,aromatics,resin and asphaltene components of paraffin-base(PB)and naphthenic-base(HB)crude oil are separated by chromatographic column.The acidic components of crude oil are extracted by compounded polar solvents and identified by methyl esterification of diazomethane.The acidic components before and after asphaltene removal are investigated by gas chromatography-mass spectrometer.The effect of four fractions in simulated oil on interfacial activity is discussed.The results show PB is rich in naphthalene series and tri-aromatic steroids,and HB has a high content of phenanthrene series,chrysene series and methylpyrene,besides higher content of naphthalene series.The long carbon chain acids in HB oil decrease significantly by asphaltenes removal,confirming the presence of heavy oil acids in asphaltene.A little amount of saturates and aromatics in simulated oil can reduce the interfacial tension(IFT).When the content of asphaltenes of simulated oil is increased,IFT is initially decreased and finally increased because of stability of asphaltenes.When resin is increased,IFT is initially increased and then decreased.Simulated oil containing the resin from naphthenic-base oil is more sensitive to alkali than that of paraffin-base resin,which can reduce the IFT between oil and water at a larger range.展开更多
基金supported in part by the National Natural Science Foundation of China Project under Grant 62075147the Suzhou Industry Technological Innovation Projects under Grant SYG202348.
文摘Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security.
基金Supported by Zhejiang Provincial Basic and Public Welfare Foundation,No.LGF22H030002Ningbo Science and Technology Program,No.2021S182+1 种基金Major Medical Scientific Research Foundation of National Health Commission of the People's Republic of China-Zhejiang Province,No.WKJ-ZJ-2341Zhejiang Province and Ningbo City Coconstructed Project of Leading Medical&Health Discipline,No.2016-S04.
文摘BACKGROUND Chronic hepatitis B virus(HBV)infection remains a major global public health problem.Chronic hepatitis B(CHB)patients can be divided into treatment indication and non-treatment indication individuals according to alanine transaminase(ALT),HBV DNA,serum hepatitis B e antigen status,disease status[liver cirrhosis,hepatocellular carcinoma(HCC),or liver failure],liver necroinflammation or fibrosis,patients’age,and family history of HCC or cirrhosis.For example,normal ALT patients in‘immune-tolerant’phase with HBV DNA higher than 10^(7)or 2×10^(7)IU/mL,and those in‘inactive-carrier’phase with HBV DNA lower than 2×10^(3)IU/mL do not require antiviral therapy.However,is it reasonable to set the defined values of HBV DNA as the fundamental basis to estimate the disease state and to determine whether to start treatment?In fact,we should pay more attention to those who do not match the treatment indications(grayzone patients both in the indeterminate phase and in the‘inactive-carrier’phase).AIM To analyze the correlation of HBV DNA level and liver histopathological severity,and to explore the significance of HBV DNA for CHB with normal ALT.METHODS From January 2017 to December 2021,a retrospective cross-sectional set of 1299 patients with chronic HBV infection(HBV DNA>30 IU/mL)who underwent liver biopsy from four hospitals,including 634 with ALT less than 40 U/L.None of the patients had received anti-HBV treatment.The degrees of liver necroinflammatory activity and liver fibrosis were evaluated according to the Metavir system.On the basis of the HBV DNA level,patients were divided into two groups:Low/moderate replication group,HBV DNA≤10^(7)IU/mL[7.00 Log IU/mL,the European Association for the Study of the Liver(EASL)guidelines]or≤2×10^(7)IU/mL[7.30 Log IU/mL,the Chinese Medical Association(CMA)guidelines];high replication group,HBV DNA>10^(7)IU/mL or>2×10^(7)IU/mL.Relevant factors(demographic characteristics,laboratory parameters and noninvasive models)for liver histopathological severity were analyzed by univariate analysis,logistics analysis and propensity score-matched analysis.RESULTS At entry,there were 21.45%,24.29%,and 30.28%of the patients had liver histopathological severities with≥A2,≥F2,and≥A2 or/and≥F2,respectively.HBV DNA level(negative correlation)and noninvasive model liver fibrosis 5 value(positive correlation)were independent risk factors for liver histopathological severities(liver necroinflammation,liver fibrosis,and treatment indication).The AUROCs of the prediction probabilities(PRE_)of the models mentioned above(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.814(95%CI:0.770-0.859),0.824(95%CI:0.785-0.863),and 0.799(95%CI:0.760-0.838),respectively.HBV DNA level(negative correlation)was still an independent risk factor when diagnostic models were excluded,the P values(<A2 vs≥A2,<F2 vs≥F2,<A2 and<F2 vs≥A2 or/and≥F2)were 0.011,0.000,and 0.000,respectively.For the propensity score-matched pairs,whether based on EASL guidelines or CMA guidelines,the group with significant liver histology damage(≥A2 or/and≥F2)showed much lower HBV DNA level than the group with non-significant liver histology damage(<A2 and<F2).Patients in the moderate replication group(with indeterminate phase)had the most serious liver disease pathologically and hematologically,followed by patients in the low replication group(with‘inactive-carrier’phase)and then the high replication group(with‘immune-tolerant’phase).CONCLUSION HBV DNA level is a negative risk factor for liver disease progression.The phase definition of CHB may be revised by whether the level of HBV DNA exceeds the detection low limit value.Patients who are in the indeterminate phase or‘inactive carriers’should receive antiviral therapy.
基金supported by grants from the Youth Doctor Collaborative Innovation Team Project(QC201803)of Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicinethe Project of Biobank(NO.YBKA201901)from Shanghai Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine+1 种基金the Shanghai Youth Top-Notch Talent Program(201809004)“Chenguang Program”supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission(19CG18)and Science and Technology Commission of Shanghai Municipality(19JC1413),Shanghai Rising-Star Program(20QA1405600).
文摘The field of plastic surgery has developed rapidly in the last couple of decades in Hong Kong and Shanghai,China.Both cities have their own educational system for training plastic surgeons.Their training programs differ in many ways,including the surgical exposure of undergraduate studies,the structure,curriculum,and operative requirements of residency training.In general,Hong Kong has a single pathway of residency training with more early clinical exposure in an undergraduate study.On the contrary,Shanghai has multiple pathways of residency training that are heavily emphasized in academic research.Both Hong Kong and Shanghai should complement each other to modify their plastic surgery training programs that will eventually benefit the field of plastic surgery education。
基金financial support by the National Natural Science Foundation of China(51474035).
文摘The saturate,aromatics,resin and asphaltene components of paraffin-base(PB)and naphthenic-base(HB)crude oil are separated by chromatographic column.The acidic components of crude oil are extracted by compounded polar solvents and identified by methyl esterification of diazomethane.The acidic components before and after asphaltene removal are investigated by gas chromatography-mass spectrometer.The effect of four fractions in simulated oil on interfacial activity is discussed.The results show PB is rich in naphthalene series and tri-aromatic steroids,and HB has a high content of phenanthrene series,chrysene series and methylpyrene,besides higher content of naphthalene series.The long carbon chain acids in HB oil decrease significantly by asphaltenes removal,confirming the presence of heavy oil acids in asphaltene.A little amount of saturates and aromatics in simulated oil can reduce the interfacial tension(IFT).When the content of asphaltenes of simulated oil is increased,IFT is initially decreased and finally increased because of stability of asphaltenes.When resin is increased,IFT is initially increased and then decreased.Simulated oil containing the resin from naphthenic-base oil is more sensitive to alkali than that of paraffin-base resin,which can reduce the IFT between oil and water at a larger range.
