Zhonghua Yi Xue Yi Chuan Xue Za Zhi Zhonghua Yixue Yichuanxue Zazhi Chinese Journal of Medical Genetics, 2004
To study the biological function of fusion gene HRX-EEN and its role in leukemogenesis, and to pr... more To study the biological function of fusion gene HRX-EEN and its role in leukemogenesis, and to provide an ideal animal model for anti-leukemia drug screening. HRX-EEN fusion gene was constructed by use of three different DNA fragments, and it was inserted into hCG transgenic vector. G(0) transgenic mice were obtained by microinjection of the recombined DNA into the pronucleus of zygotes, followed by implantation of the injected zygotes into pseudopregnant mice. The integration of the transgene was tested by PCR and its expression by reverse transcription-polymerase chain reaction (RT-PCR). The sequence of recombined HRX-EEN gene was confirmed by sequencing. PCR testing revealed a total of 7 G(0) transgenic mice, these mice were then mated with C57 wild type mice. Except mouse No. 35 that died, the others all had their F1 offsprings. From these 6 lines of transgenic mice, HRX-EEN gene was found to be stably expressed in 3 lines by RT-PCR. Up to now, all transgenic mice expressing the fusion gene have no obvious abnormal phenotypes. A transgenic mice model in which the HRX-EEN fusion gene can be stably expressed has been established.
Zhonghua Xin Xue Guan Bing Za Zhi Chinese Journal of Cardiovascular Diseases, 2010
To evaluate the efficacy of one-stop hybrid coronary revascularization [simultaneous minimally in... more To evaluate the efficacy of one-stop hybrid coronary revascularization [simultaneous minimally invasive direct coronary artery bypass surgery (MIDCAB) and percutaneous coronary intervention (PCI) procedures performed in an enhanced (or called "hybrid") operative unit] for the treatment of unprotected left main coronary artery (ULMCA) disease. From June 2007 to April 2009, 14 patients [13 male, mean age: (60.4 +/- 15.4) years] underwent the one-stop hybrid approach in the "hybrid" operating room. Proximal lesions were evidenced in 5 patients and distal or bifurcation lesions in 11 patients. MIDCAB procedure for grafting of the left intramammary artery (LIMA) with the left anterior descending (LAD) artery was first performed via lower partial ministernotomy on the beating heart, followed by PCI on the LMCA disease and non-LAD coronary lesions. Operation was successful in all patients underwent the one-stop hybrid procedure. LIMA grafts were used in all 14 patients and confirmed to be patent by angiography. A total of 25 non-LAD coronary lesions were treated by PCI and 29 stents (27 drug-eluting stents and 2 bare-mental stents) were implanted to 23 lesions and coronary angioplasty was performed in the remaining lesions. There was no death, perioperative myocardial infarction, stroke or repeat revascularization during the procedure and the follow-up period. All the patients remained free from angina during the 7.9 months (range 1 - 15 months) follow-up period. LIMA grafts and stents were patent in 5 patients at 1-year follow-up. Our initial experience demonstrates that one-stop hybrid coronary revascularization provides a reasonable, feasible and safe alternative for selected patients with LMCA diseases.
Zhonghua Wai Ke Za Zhi Chinese Journal of Surgery, Sep 1, 2005
To evaluate the feasibility and clinical effect of transperitoneal laparoscopic enucleation of re... more To evaluate the feasibility and clinical effect of transperitoneal laparoscopic enucleation of renal angiomyolipoma (RAML) without obstruction of renal pedicle. Ten patients with renal angioleiomyoma (tumor diameter < 4 cm) were operated by transperitoneal laparoscopy without obstruction of renal pedicle. The operating time, blood loss, hospital stay after operation, intraoperative and postoperative complications and the operative effect were observed. All the 10 patients underwent the operation successfully. The average operating time was 90 min, average blood loss was 80 ml, the average hospital stay after operation was 7 d. No intraoperative or postoperative complications occurred. Follow-up period was 3-19 months and no tumor metastasized or occurred again. This mininvasive procedure is a more precise and complete method than before, which can minimize the blood loss and make patients recover quickly, so it is well worth clinical applying.
An often-noted feature of computational agents research is its interdisciplinary nature. The grow... more An often-noted feature of computational agents research is its interdisciplinary nature. The growing use of computational models in social, biological and economic systems raises many question and concerns. Platforms such as Swarm enable researchers to construct detailed, robust computational models. The availability of these platforms may speed the pace of the computational revolution and open new areas of interest. To test the usability and suitability of Swarm to model social-economy phenomena, we have made some simple economic models implemented in Swarm. First part of the paper may discuss briefly the advantage of agent simulation in modeling economic issues and why we chose Swarm as the platform. What followed is the description of the models and results from runs of the model are also reported. The last part may introduce some of our own insight in the realm of agent-based micro simulation model of the economy
Background. This study sought to compare early and midterm clinical outcomes of a simultaneous hy... more Background. This study sought to compare early and midterm clinical outcomes of a simultaneous hybrid coronary revascularization procedure with those in a propensity-matched subset of patients undergoing conventional off-pump coronary artery bypass grafting.
The hybrid procedure for coronary heart disease combines minimally invasive coronary artery bypas... more The hybrid procedure for coronary heart disease combines minimally invasive coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) and is an alternative to revascularization treatment. We sought to assess the predictive value of four risk-stratification models for risk assessment of major adverse cardiac and cerebrovascular events (MACCE) in patients with multivessel disease undergoing hybrid coronary revascularization. The data of 120 patients were retrospectively collected and the SYNTAX score, EuroSCORE, SinoSCORE and the Global Risk Classification (GRC) calculated for each patient. The outcomes of interest were 2.7-year incidences of MACCE, including death, myocardial infarction, stroke, and any-vessel revascularization. During a mean of 2.7-year follow-up, actuarial survival was 99.17%, and no myocardial infarctions occurred. The discriminatory power (area under curve (AUC)) of the SYNTAX score, EuroSCORE, SinoSCORE and GRC for 2.7-year MACCE was 0.60 (95% confidence interval 0.42 - 0.77), 0.65 (0.47 - 0.82), 0.57 (0.39 - 0.75) and 0.65 (0.46 - 0.83), respectively. The calibration characteristics of the SYNTAX score, EuroSCORE, SinoSCORE and GRC were 3.92 (P = 0.86), 5.39 (P = 0.37), 13.81 (P = 0.32) and 0.02 (P = 0.89), respectively. In patients with multivessel disease undergoing a hybrid procedure, the SYNTAX score, EuroSCORE, SinoSCORE and GRC were inaccurate in predicting MACCE. Modifying risk-stratification models to improve the predictive value for a hybrid procedure is needed.
International Journal of Distributed Sensor Networks, May 13, 2015
This paper presents a tag localization algorithm based on the time-difference-of-arrival (TDOA) o... more This paper presents a tag localization algorithm based on the time-difference-of-arrival (TDOA) of mobile tag signal for asynchronous wireless sensor network (WSN) with N anchors (nodes with known locations) and a large number of mobile tags. To obtain time synchronization, all anchors broadcast signals periodically; relative clock offsets and skews of anchor pairs are estimated by the least-square (LS) method using the times-of-arrival (TOAs) of broadcast signals at anchors. When a tag transmits signal, the TOA of tag signal at each anchor is stamped and errors in original TDOAs of tag signal due to relative clock offsets and skews of anchor pairs are eliminated. Based on Gaussian noise model, maximum likelihood estimation (MLE) for the tag position is obtained. Performance issues are addressed by evaluating the Cramér-Rao lower bound of synchronization and localization algorithms. Since the tag can be located via a single transmission, least power consumption of tag is required, and large number of tags can be served in WSN. The proposed algorithm is simple and effective, with performance close to that of synchronous TDOA algorithm.
2009 International Conference on Communications, Circuits and Systems, 2009
ABSTRACT Multi-receiver signcryption is very useful to secure group communications. In 2007, Yu e... more ABSTRACT Multi-receiver signcryption is very useful to secure group communications. In 2007, Yu et al. proposed an efficient multi-receiver identity-based signcryption scheme. However, Selvi et al. showed that Yu et al.'s scheme does not satisfy the unforgeability, and presented an improved scheme. In this paper, we show that both Yu et al.'s scheme and Selvi et al.'s scheme do not satisfy the confidentiality. Then we propose a new multi-receiver identity-based signcryption scheme. We prove its semantical security under the q-Bilinear Diffie-Hellman inversion problem assumption and its unforgeability under the q-Strong Diffie-Hellman problem assumption in the random oracle model. This new scheme turns out to be more efficient than all other schemes proposed to date.
... After that, Shim (2006) proposed another efficient ID-based proxy signature scheme with more ... more ... After that, Shim (2006) proposed another efficient ID-based proxy signature scheme with more tighter ... A malicious PKG can frame an innocent user by forging the user's signature. ... concept was introduced to suppress the inherent key-escrow property of identity-based public key ...
Due to their surface modification capabilities, tethered polymer chains have been a research focu... more Due to their surface modification capabilities, tethered polymer chains have been a research focus for several years. Experimental and theoretical work has been done to understand the conformations and interactions of these systems at varying tethering densities. A new technique developed in our group makes it possible to use single crystals of crystalline-amorphous diblock copolymers to study tethered polymer chains. These systems have controlled density through defined fold numbers and controlled MW through living polymerization. Zheng and coworkers found that the reduced tethering density is 3.7 for the onset of interchain interaction and 14.3 for the highly-stretched brush. This work provides, for the first time, the values of these two onsets with high certainty; however, the systems studied do not provide general results. Both systems had repulsive interactions between the surface and the tethered chains. In order to broaden the scope of the physics behind tethered polymer chains, the study should include systems with attractive potentials. Preliminary studies of one such system, PMMA-b-PLLA, will be presented.
Privacy and anonymity have become two factors of increasing importance in auction protocol. This ... more Privacy and anonymity have become two factors of increasing importance in auction protocol. This paper provides an efficient sealed-bid electronic auction protocol based on the technique of ring signature and verifiable technique of encryption key chain. The peculiar characteristics of our protocol are non-repudiation of bidders but preserving their anonymity and allowing the auctioneer to determine the wining bid without revealing the losing bid. Our protocol has additional characteristics such as public verifiability, unforgeability, correctness and fairness.
2008 3rd International Conference on Innovative Computing Information and Control, 2008
Cutting stock problems can be found in various industries. They arise, for examples, with machini... more Cutting stock problems can be found in various industries. They arise, for examples, with machining, timber processing, paper-making, etc. 1.5-dimensional cutting stock problem is a problem between one-dimensional cutting and two-dimensional cutting. In this study, a two-stage approach is developed for 1.5 dimensional cutting problem. 1.5-dimensional cutting problem is changed into one-dimensional cutting problem in the first step. An initial
2008 International Conference on Communications, Circuits and Systems, 2008
Signcryption is a cryptographic primitive that performs digital signature and public key encrypti... more Signcryption is a cryptographic primitive that performs digital signature and public key encryption simultaneously, at lower computational costs and communication overheads than the signature-then-encryption approach. In 2005, Huang et al. proposed an identity-based ring signcryption scheme by combining the concepts of identity-based ring signature and signcryption together. However, their scheme is computationally inefficient, since the number of pairing computations grows
Journal of Electroanalytical Chemistry, Apr 15, 2009
Scanning electrochemical microscopy (SECM) is developed as a powerful approach to electrochemical... more Scanning electrochemical microscopy (SECM) is developed as a powerful approach to electrochemical characterization of individual one-dimensional (1D) nanostructures under unbiased conditions. 1D nanostructures comprise high-aspect-ratio materials with both nanoscale and macroscale dimensions such as nanowires, nanotubes, nanobelts, and nanobands. Finite element simulations demonstrate that the feedback current at a disk-shaped ultramicroelectrode tip positioned above an unbiased nanoband, as prepared on an insulating substrate, is sensitive to finite dimensions of the band, i.e., micrometer length, nanometer width, and nanometer height from the insulating surface. The electron-transfer rate of a redox mediator at the nanoband surface depends not only on the intrinsic rate but also on the open-circuit potential of the nanoband, which is determined by the dimensions of the nanoband as well as the tip inner and outer radii, and tip-substrate distance. The theoretical predictions are confirmed experimentally by employing Au nanobands as fabricated on a SiO 2 surface by electron-beam lithography, thereby yielding well defined dimensions of 100 or 500 nm in width, 47 nm in height, and 50 μm in length. A 100 nm-wide nanoband can be detected by SECM imaging with ∼2 μm-diameter tips although the tip feedback current is compromised by finite electron-transfer kinetics for Ru(NH 3 ) 6 3+ at the nanoband surface.
Bioorganic Medicinal Chemistry Letters, Mar 15, 2011
The neurokinin-3 (NK3) receptor is regarded as a potential novel target for treating patients wit... more The neurokinin-3 (NK3) receptor is regarded as a potential novel target for treating patients with schizophrenia. Herein we report the synthesis and SAR of a series of C3-alkylsulfoxide substituted quinolines as potent NK3 receptor antagonists. These compounds have excellent NK3 functional activity, good selectivity and drug-like properties. Several key compounds have good in vitro/in vivo DMPK characteristics, and are active in a gerbil locomotor activity model.
Proxy ring signature allows proxy signer to sign messages on behalf of the original signer while ... more Proxy ring signature allows proxy signer to sign messages on behalf of the original signer while providing anonymity. Certificateless public key cryptography was first introduced by Al-Riyami and Paterson in Asiacrypt 2003. In certificateless cryptography, it does not require the use of certificates to guarantee the authenticity of users' public keys. Meanwhile, certificateless cryptography does not have the key escrow problem, which seems to be inherent in the Identity-based cryptography. In this paper, we introduce the notion of proxy ring signature into certificateless public key cryptography and propose a concrete certificateless proxy ring signature scheme. The security models of certificateless proxy ring signature are also formalized. The security of the proposed scheme can be proved to be equivalent to the computational Diffie-Hellman problem in the random oracle with a tight reduction.
Exploring pH-insuspensible catalysts for pollutant treatments is still a challenge because of the... more Exploring pH-insuspensible catalysts for pollutant treatments is still a challenge because of the pH-dependent catalyst stability. A recently developed manganese complex, Mn(Me2EBC)Cl2, (Me2EBC: 4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane) was investigated to decolorize dyes in the pH range of 1-13 using H2O2 as the oxidant, and its stability in service was examined by periodically adding fresh dye and oxidant. The results display that this manganese complex is capable of decoloring dye in both acid and base and keeping activity for a long service period. In addition, its modified analogue, Mn(Et2EBC)Cl2, can perform efficient decolorization in the whole pH range from pH 1 to 13. Combinatorial methods including stoichiometric treatments of dye with freshly synthetic manganese(IV) complex, utilization of radical scavenger, and intermediate analysis by UV-visible spectrophotometry were applied for its mechanistic studies, and a manganese(IV) hydroperoxide intermediate has been suspected to serve as the key active species in decolorization.
Here we report on novel application of scanning electrochemical microscopy (SECM) to enable spati... more Here we report on novel application of scanning electrochemical microscopy (SECM) to enable spatially resolved electrochemical characterization of individual single-walled carbon nanotube (SWNT). The feedback imaging mode of SECM was employed to detect a pristine SWNT (~1.6 nm in diameter and ~2 mm in length) grown horizontally on a SiO 2 surface by chemical vapor deposition. The resulting image demonstrates that the individual nanotube under an unbiased condition is highly active for the redox reaction of ferrocenylmethyltrimethylammonium used as a mediator. Micrometer-scale resolution of the image is determined by the diameter of a disk-shaped SECM probe rather than by the nanotube diameter as assessed using 1.5 and 10 μm-diameter probes. Interestingly, the long SWNT is readily detectable using the larger probe although the active SWNT covers only ~0.05 % of the insulating surface just under the tip. This high sensitivity of the SECM feedback method is ascribed to efficient mass transport and facile electron transfer at the individual SWNT.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi Zhonghua Yixue Yichuanxue Zazhi Chinese Journal of Medical Genetics, 2004
To study the biological function of fusion gene HRX-EEN and its role in leukemogenesis, and to pr... more To study the biological function of fusion gene HRX-EEN and its role in leukemogenesis, and to provide an ideal animal model for anti-leukemia drug screening. HRX-EEN fusion gene was constructed by use of three different DNA fragments, and it was inserted into hCG transgenic vector. G(0) transgenic mice were obtained by microinjection of the recombined DNA into the pronucleus of zygotes, followed by implantation of the injected zygotes into pseudopregnant mice. The integration of the transgene was tested by PCR and its expression by reverse transcription-polymerase chain reaction (RT-PCR). The sequence of recombined HRX-EEN gene was confirmed by sequencing. PCR testing revealed a total of 7 G(0) transgenic mice, these mice were then mated with C57 wild type mice. Except mouse No. 35 that died, the others all had their F1 offsprings. From these 6 lines of transgenic mice, HRX-EEN gene was found to be stably expressed in 3 lines by RT-PCR. Up to now, all transgenic mice expressing the fusion gene have no obvious abnormal phenotypes. A transgenic mice model in which the HRX-EEN fusion gene can be stably expressed has been established.
Zhonghua Xin Xue Guan Bing Za Zhi Chinese Journal of Cardiovascular Diseases, 2010
To evaluate the efficacy of one-stop hybrid coronary revascularization [simultaneous minimally in... more To evaluate the efficacy of one-stop hybrid coronary revascularization [simultaneous minimally invasive direct coronary artery bypass surgery (MIDCAB) and percutaneous coronary intervention (PCI) procedures performed in an enhanced (or called "hybrid") operative unit] for the treatment of unprotected left main coronary artery (ULMCA) disease. From June 2007 to April 2009, 14 patients [13 male, mean age: (60.4 +/- 15.4) years] underwent the one-stop hybrid approach in the "hybrid" operating room. Proximal lesions were evidenced in 5 patients and distal or bifurcation lesions in 11 patients. MIDCAB procedure for grafting of the left intramammary artery (LIMA) with the left anterior descending (LAD) artery was first performed via lower partial ministernotomy on the beating heart, followed by PCI on the LMCA disease and non-LAD coronary lesions. Operation was successful in all patients underwent the one-stop hybrid procedure. LIMA grafts were used in all 14 patients and confirmed to be patent by angiography. A total of 25 non-LAD coronary lesions were treated by PCI and 29 stents (27 drug-eluting stents and 2 bare-mental stents) were implanted to 23 lesions and coronary angioplasty was performed in the remaining lesions. There was no death, perioperative myocardial infarction, stroke or repeat revascularization during the procedure and the follow-up period. All the patients remained free from angina during the 7.9 months (range 1 - 15 months) follow-up period. LIMA grafts and stents were patent in 5 patients at 1-year follow-up. Our initial experience demonstrates that one-stop hybrid coronary revascularization provides a reasonable, feasible and safe alternative for selected patients with LMCA diseases.
Zhonghua Wai Ke Za Zhi Chinese Journal of Surgery, Sep 1, 2005
To evaluate the feasibility and clinical effect of transperitoneal laparoscopic enucleation of re... more To evaluate the feasibility and clinical effect of transperitoneal laparoscopic enucleation of renal angiomyolipoma (RAML) without obstruction of renal pedicle. Ten patients with renal angioleiomyoma (tumor diameter < 4 cm) were operated by transperitoneal laparoscopy without obstruction of renal pedicle. The operating time, blood loss, hospital stay after operation, intraoperative and postoperative complications and the operative effect were observed. All the 10 patients underwent the operation successfully. The average operating time was 90 min, average blood loss was 80 ml, the average hospital stay after operation was 7 d. No intraoperative or postoperative complications occurred. Follow-up period was 3-19 months and no tumor metastasized or occurred again. This mininvasive procedure is a more precise and complete method than before, which can minimize the blood loss and make patients recover quickly, so it is well worth clinical applying.
An often-noted feature of computational agents research is its interdisciplinary nature. The grow... more An often-noted feature of computational agents research is its interdisciplinary nature. The growing use of computational models in social, biological and economic systems raises many question and concerns. Platforms such as Swarm enable researchers to construct detailed, robust computational models. The availability of these platforms may speed the pace of the computational revolution and open new areas of interest. To test the usability and suitability of Swarm to model social-economy phenomena, we have made some simple economic models implemented in Swarm. First part of the paper may discuss briefly the advantage of agent simulation in modeling economic issues and why we chose Swarm as the platform. What followed is the description of the models and results from runs of the model are also reported. The last part may introduce some of our own insight in the realm of agent-based micro simulation model of the economy
Background. This study sought to compare early and midterm clinical outcomes of a simultaneous hy... more Background. This study sought to compare early and midterm clinical outcomes of a simultaneous hybrid coronary revascularization procedure with those in a propensity-matched subset of patients undergoing conventional off-pump coronary artery bypass grafting.
The hybrid procedure for coronary heart disease combines minimally invasive coronary artery bypas... more The hybrid procedure for coronary heart disease combines minimally invasive coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) and is an alternative to revascularization treatment. We sought to assess the predictive value of four risk-stratification models for risk assessment of major adverse cardiac and cerebrovascular events (MACCE) in patients with multivessel disease undergoing hybrid coronary revascularization. The data of 120 patients were retrospectively collected and the SYNTAX score, EuroSCORE, SinoSCORE and the Global Risk Classification (GRC) calculated for each patient. The outcomes of interest were 2.7-year incidences of MACCE, including death, myocardial infarction, stroke, and any-vessel revascularization. During a mean of 2.7-year follow-up, actuarial survival was 99.17%, and no myocardial infarctions occurred. The discriminatory power (area under curve (AUC)) of the SYNTAX score, EuroSCORE, SinoSCORE and GRC for 2.7-year MACCE was 0.60 (95% confidence interval 0.42 - 0.77), 0.65 (0.47 - 0.82), 0.57 (0.39 - 0.75) and 0.65 (0.46 - 0.83), respectively. The calibration characteristics of the SYNTAX score, EuroSCORE, SinoSCORE and GRC were 3.92 (P = 0.86), 5.39 (P = 0.37), 13.81 (P = 0.32) and 0.02 (P = 0.89), respectively. In patients with multivessel disease undergoing a hybrid procedure, the SYNTAX score, EuroSCORE, SinoSCORE and GRC were inaccurate in predicting MACCE. Modifying risk-stratification models to improve the predictive value for a hybrid procedure is needed.
International Journal of Distributed Sensor Networks, May 13, 2015
This paper presents a tag localization algorithm based on the time-difference-of-arrival (TDOA) o... more This paper presents a tag localization algorithm based on the time-difference-of-arrival (TDOA) of mobile tag signal for asynchronous wireless sensor network (WSN) with N anchors (nodes with known locations) and a large number of mobile tags. To obtain time synchronization, all anchors broadcast signals periodically; relative clock offsets and skews of anchor pairs are estimated by the least-square (LS) method using the times-of-arrival (TOAs) of broadcast signals at anchors. When a tag transmits signal, the TOA of tag signal at each anchor is stamped and errors in original TDOAs of tag signal due to relative clock offsets and skews of anchor pairs are eliminated. Based on Gaussian noise model, maximum likelihood estimation (MLE) for the tag position is obtained. Performance issues are addressed by evaluating the Cramér-Rao lower bound of synchronization and localization algorithms. Since the tag can be located via a single transmission, least power consumption of tag is required, and large number of tags can be served in WSN. The proposed algorithm is simple and effective, with performance close to that of synchronous TDOA algorithm.
2009 International Conference on Communications, Circuits and Systems, 2009
ABSTRACT Multi-receiver signcryption is very useful to secure group communications. In 2007, Yu e... more ABSTRACT Multi-receiver signcryption is very useful to secure group communications. In 2007, Yu et al. proposed an efficient multi-receiver identity-based signcryption scheme. However, Selvi et al. showed that Yu et al.'s scheme does not satisfy the unforgeability, and presented an improved scheme. In this paper, we show that both Yu et al.'s scheme and Selvi et al.'s scheme do not satisfy the confidentiality. Then we propose a new multi-receiver identity-based signcryption scheme. We prove its semantical security under the q-Bilinear Diffie-Hellman inversion problem assumption and its unforgeability under the q-Strong Diffie-Hellman problem assumption in the random oracle model. This new scheme turns out to be more efficient than all other schemes proposed to date.
... After that, Shim (2006) proposed another efficient ID-based proxy signature scheme with more ... more ... After that, Shim (2006) proposed another efficient ID-based proxy signature scheme with more tighter ... A malicious PKG can frame an innocent user by forging the user's signature. ... concept was introduced to suppress the inherent key-escrow property of identity-based public key ...
Due to their surface modification capabilities, tethered polymer chains have been a research focu... more Due to their surface modification capabilities, tethered polymer chains have been a research focus for several years. Experimental and theoretical work has been done to understand the conformations and interactions of these systems at varying tethering densities. A new technique developed in our group makes it possible to use single crystals of crystalline-amorphous diblock copolymers to study tethered polymer chains. These systems have controlled density through defined fold numbers and controlled MW through living polymerization. Zheng and coworkers found that the reduced tethering density is 3.7 for the onset of interchain interaction and 14.3 for the highly-stretched brush. This work provides, for the first time, the values of these two onsets with high certainty; however, the systems studied do not provide general results. Both systems had repulsive interactions between the surface and the tethered chains. In order to broaden the scope of the physics behind tethered polymer chains, the study should include systems with attractive potentials. Preliminary studies of one such system, PMMA-b-PLLA, will be presented.
Privacy and anonymity have become two factors of increasing importance in auction protocol. This ... more Privacy and anonymity have become two factors of increasing importance in auction protocol. This paper provides an efficient sealed-bid electronic auction protocol based on the technique of ring signature and verifiable technique of encryption key chain. The peculiar characteristics of our protocol are non-repudiation of bidders but preserving their anonymity and allowing the auctioneer to determine the wining bid without revealing the losing bid. Our protocol has additional characteristics such as public verifiability, unforgeability, correctness and fairness.
2008 3rd International Conference on Innovative Computing Information and Control, 2008
Cutting stock problems can be found in various industries. They arise, for examples, with machini... more Cutting stock problems can be found in various industries. They arise, for examples, with machining, timber processing, paper-making, etc. 1.5-dimensional cutting stock problem is a problem between one-dimensional cutting and two-dimensional cutting. In this study, a two-stage approach is developed for 1.5 dimensional cutting problem. 1.5-dimensional cutting problem is changed into one-dimensional cutting problem in the first step. An initial
2008 International Conference on Communications, Circuits and Systems, 2008
Signcryption is a cryptographic primitive that performs digital signature and public key encrypti... more Signcryption is a cryptographic primitive that performs digital signature and public key encryption simultaneously, at lower computational costs and communication overheads than the signature-then-encryption approach. In 2005, Huang et al. proposed an identity-based ring signcryption scheme by combining the concepts of identity-based ring signature and signcryption together. However, their scheme is computationally inefficient, since the number of pairing computations grows
Journal of Electroanalytical Chemistry, Apr 15, 2009
Scanning electrochemical microscopy (SECM) is developed as a powerful approach to electrochemical... more Scanning electrochemical microscopy (SECM) is developed as a powerful approach to electrochemical characterization of individual one-dimensional (1D) nanostructures under unbiased conditions. 1D nanostructures comprise high-aspect-ratio materials with both nanoscale and macroscale dimensions such as nanowires, nanotubes, nanobelts, and nanobands. Finite element simulations demonstrate that the feedback current at a disk-shaped ultramicroelectrode tip positioned above an unbiased nanoband, as prepared on an insulating substrate, is sensitive to finite dimensions of the band, i.e., micrometer length, nanometer width, and nanometer height from the insulating surface. The electron-transfer rate of a redox mediator at the nanoband surface depends not only on the intrinsic rate but also on the open-circuit potential of the nanoband, which is determined by the dimensions of the nanoband as well as the tip inner and outer radii, and tip-substrate distance. The theoretical predictions are confirmed experimentally by employing Au nanobands as fabricated on a SiO 2 surface by electron-beam lithography, thereby yielding well defined dimensions of 100 or 500 nm in width, 47 nm in height, and 50 μm in length. A 100 nm-wide nanoband can be detected by SECM imaging with ∼2 μm-diameter tips although the tip feedback current is compromised by finite electron-transfer kinetics for Ru(NH 3 ) 6 3+ at the nanoband surface.
Bioorganic Medicinal Chemistry Letters, Mar 15, 2011
The neurokinin-3 (NK3) receptor is regarded as a potential novel target for treating patients wit... more The neurokinin-3 (NK3) receptor is regarded as a potential novel target for treating patients with schizophrenia. Herein we report the synthesis and SAR of a series of C3-alkylsulfoxide substituted quinolines as potent NK3 receptor antagonists. These compounds have excellent NK3 functional activity, good selectivity and drug-like properties. Several key compounds have good in vitro/in vivo DMPK characteristics, and are active in a gerbil locomotor activity model.
Proxy ring signature allows proxy signer to sign messages on behalf of the original signer while ... more Proxy ring signature allows proxy signer to sign messages on behalf of the original signer while providing anonymity. Certificateless public key cryptography was first introduced by Al-Riyami and Paterson in Asiacrypt 2003. In certificateless cryptography, it does not require the use of certificates to guarantee the authenticity of users' public keys. Meanwhile, certificateless cryptography does not have the key escrow problem, which seems to be inherent in the Identity-based cryptography. In this paper, we introduce the notion of proxy ring signature into certificateless public key cryptography and propose a concrete certificateless proxy ring signature scheme. The security models of certificateless proxy ring signature are also formalized. The security of the proposed scheme can be proved to be equivalent to the computational Diffie-Hellman problem in the random oracle with a tight reduction.
Exploring pH-insuspensible catalysts for pollutant treatments is still a challenge because of the... more Exploring pH-insuspensible catalysts for pollutant treatments is still a challenge because of the pH-dependent catalyst stability. A recently developed manganese complex, Mn(Me2EBC)Cl2, (Me2EBC: 4,11-dimethyl-1,4,8,11-tetraazabicyclo[6.6.2]hexadecane) was investigated to decolorize dyes in the pH range of 1-13 using H2O2 as the oxidant, and its stability in service was examined by periodically adding fresh dye and oxidant. The results display that this manganese complex is capable of decoloring dye in both acid and base and keeping activity for a long service period. In addition, its modified analogue, Mn(Et2EBC)Cl2, can perform efficient decolorization in the whole pH range from pH 1 to 13. Combinatorial methods including stoichiometric treatments of dye with freshly synthetic manganese(IV) complex, utilization of radical scavenger, and intermediate analysis by UV-visible spectrophotometry were applied for its mechanistic studies, and a manganese(IV) hydroperoxide intermediate has been suspected to serve as the key active species in decolorization.
Here we report on novel application of scanning electrochemical microscopy (SECM) to enable spati... more Here we report on novel application of scanning electrochemical microscopy (SECM) to enable spatially resolved electrochemical characterization of individual single-walled carbon nanotube (SWNT). The feedback imaging mode of SECM was employed to detect a pristine SWNT (~1.6 nm in diameter and ~2 mm in length) grown horizontally on a SiO 2 surface by chemical vapor deposition. The resulting image demonstrates that the individual nanotube under an unbiased condition is highly active for the redox reaction of ferrocenylmethyltrimethylammonium used as a mediator. Micrometer-scale resolution of the image is determined by the diameter of a disk-shaped SECM probe rather than by the nanotube diameter as assessed using 1.5 and 10 μm-diameter probes. Interestingly, the long SWNT is readily detectable using the larger probe although the active SWNT covers only ~0.05 % of the insulating surface just under the tip. This high sensitivity of the SECM feedback method is ascribed to efficient mass transport and facile electron transfer at the individual SWNT.
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Papers by Hui Xiong