Objective: To evaluate the effectiveness of intraoperative radiotherapy (IORT) in combination with regional chemotherapy in the treatment of advanced pancreatic carcinoma.Methods: 17 patients with advanced pancreatic ...Objective: To evaluate the effectiveness of intraoperative radiotherapy (IORT) in combination with regional chemotherapy in the treatment of advanced pancreatic carcinoma.Methods: 17 patients with advanced pancreatic adenocarcinoma were treated with IORT and regional chemotherapy with 5-FU, Epirubucin and Mitomycin, and 6 cases accepted external radiotherapy postoperatively.Results: 35.29% (6/17) of the patients were clinical benefit responders and 23.53% (4/17) had a partial response. The median survival time was 11 months and the 1-year survival rate was 35.29% (6/17)Conclusion: IORT in combination with regional chemotherapy had a good impact on clinical benefit without severe side effects in locally advanced pancreatic carcinoma and led to a significant prolongation of the survival time. Key words pancreatic cancer - intraoperative radiotherapy - chemotherapy展开更多
Partially hydrolyzed polyacrylamide （HPAM） has been widely used for water shut-off and profile control to enhance oil recovery. Herein, we reported a novel technique by which the crosslinking between HPAM and Cr3＋ ...Partially hydrolyzed polyacrylamide （HPAM） has been widely used for water shut-off and profile control to enhance oil recovery. Herein, we reported a novel technique by which the crosslinking between HPAM and Cr3＋ in aqueous solutions at 60 ℃ can be delayed effectively. Citric acid was selected as an organic complexing agent of Cr3＋ so that the crosslinking between HPAM and Cr3＋ can be prevented completely. Due to the decomposi- tion of the bicarbonate （HCO3-） embedded in solution, CO2 released from solution and the pH value of solution increased gradually. The degree of ionization of HPAM and its ability to complex with Cr3＋ increased accordingly. When the complexation of Cr3＋ with HPAM is stronger than that with citric acid, the viscosity of the HPAM solution increased signif- icantly. Under the closed condition, together with the existence of potassium dihydrogen phosphate （KH2PO4）, the release of CO2 was very slow and the condition was highly con- trolled so that the ionization of HPAM was prevented initially. Furthermore, the hydrogen bonding interactions between HPAM and melamine embedded in solution previously also postponed the ionization of HPAM. As a result, the crosslinking between HPAM and Cr3＋ can be delayed for almost one month, completely meeting the requirements for deep water shut-off and profile control to enhance oil recovery.展开更多
In order to improve the throughput of cognitive radio(CR), optimization of sensing time and cooperative user allocation for OR-rule cooperative spectrum sensing was investigated in a CR network that includes multiple ...In order to improve the throughput of cognitive radio(CR), optimization of sensing time and cooperative user allocation for OR-rule cooperative spectrum sensing was investigated in a CR network that includes multiple users and one fusion center. The frame structure of cooperative spectrum sensing was divided into multiple transmission time slots and one sensing time slot consisting of local energy detection and cooperative overhead. An optimization problem was formulated to maximize the throughput of CR network, subject to the constraints of both false alarm probability and detection probability. A joint optimization algorithm of sensing time and number of users was proposed to solve this optimization problem with low time complexity. An allocation algorithm of cooperative users was proposed to preferentially allocate the users to the channels with high utilization probability. The simulation results show that the significant improvement on the throughput can be achieved through the proposed joint optimization and allocation algorithms.展开更多
A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populati...A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populations in hybrid rice cropping system. The mineral N, Pand K fertilizers (as urea, calcium superphosphate and KCl respectively) were incorporated at 100,25, and 100 kg ha^(-1), respectively, and the various pesticides were applied at the recommendedrates. The results of the experiment demonstrated a decline in the microbial abundance and soilmicrobial biomass phospholipid contents with the advancement of crop growth, and significant changesin substrate utilization pattern of soil microbial population studied were observed with differentmanagement practices and at different growth stages. The principal component analysis (PCA) usingall 95-carbon sources (BIOLOG plates) gave good differentiation among the treatments, indicatingthat they have different patterns of carbon utilization under different habitats. The data showedthat diversity in microbial community continuously changed with the progression in crop stage,particularly at physiological maturity (PM) stage that was evident from the utilization of differentcarbon sources at various crop stages.展开更多
The universality of the application of wireless sensor networks( WSN) makes more attention be paid on the security problem. Node authentication is not only the basis of network security,but also the premise of key man...The universality of the application of wireless sensor networks( WSN) makes more attention be paid on the security problem. Node authentication is not only the basis of network security,but also the premise of key management and secure routing protocol. Although the signature mechanism based on symmetric encryption is high in energy efficiency,it is vulnerable to be attacked and there is a time delay during authentication. Traditional public key encryption mechanism with improvement in security brings in complex algorithm and costs much time,which is not suitable for WSN. In this paper,a signature authentication mechanism,an optimized variant Bellare Namprempre Neven( OvBNN) is presented to quickly complete the authentication by mutual cooperation between nodes so as to make the nodes use the intermediate calculation results of their neighbor nodes directly.Simulation results show that the proposed mechanism is superior to traditional authentication mechanisms both in energy consumption and authentication time.展开更多
Internet of Things （IoT） refers to an infrastructure which enables the forms of com- munication and collaboration between people and things, and between things themselves. In order to improve its performance, we pre...Internet of Things （IoT） refers to an infrastructure which enables the forms of com- munication and collaboration between people and things, and between things themselves. In order to improve its performance, we present a tradeoff between bandwidth and energy con- sumption in the loT in this paper. A service providing model is built to find the relation- ship between bandwidth and energy consump- tion using a cooperative differential game mo- del. The game solution is gotten in the condi- tion of grand coalition, feedback Nash equili- brium and intermediate coalitions and an allo- cation policy is obtain by Shapley theory. The results are shown as follows. Firstly, the per- formance of IoT decreases with the increasing of bandwidth cost or with the decreasing of en- ergy cost; secondly, all the nodes in the IoT com- posing a grand coalition can save bandwidth and energy consumption; thirdly, when the fac- tors of bandwidth cost and energy cost are eq- ual, the obtained number of provided services is an optimised value which is the trade-off between energy and bandwidth consumption.展开更多
文摘Objective: To evaluate the effectiveness of intraoperative radiotherapy (IORT) in combination with regional chemotherapy in the treatment of advanced pancreatic carcinoma.Methods: 17 patients with advanced pancreatic adenocarcinoma were treated with IORT and regional chemotherapy with 5-FU, Epirubucin and Mitomycin, and 6 cases accepted external radiotherapy postoperatively.Results: 35.29% (6/17) of the patients were clinical benefit responders and 23.53% (4/17) had a partial response. The median survival time was 11 months and the 1-year survival rate was 35.29% (6/17)Conclusion: IORT in combination with regional chemotherapy had a good impact on clinical benefit without severe side effects in locally advanced pancreatic carcinoma and led to a significant prolongation of the survival time. Key words pancreatic cancer - intraoperative radiotherapy - chemotherapy
基金supported by the National Natural Science Foundation of China(No.51273189)the National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2016ZX05016)the National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2016ZX05046)
文摘Partially hydrolyzed polyacrylamide （HPAM） has been widely used for water shut-off and profile control to enhance oil recovery. Herein, we reported a novel technique by which the crosslinking between HPAM and Cr3＋ in aqueous solutions at 60 ℃ can be delayed effectively. Citric acid was selected as an organic complexing agent of Cr3＋ so that the crosslinking between HPAM and Cr3＋ can be prevented completely. Due to the decomposi- tion of the bicarbonate （HCO3-） embedded in solution, CO2 released from solution and the pH value of solution increased gradually. The degree of ionization of HPAM and its ability to complex with Cr3＋ increased accordingly. When the complexation of Cr3＋ with HPAM is stronger than that with citric acid, the viscosity of the HPAM solution increased signif- icantly. Under the closed condition, together with the existence of potassium dihydrogen phosphate （KH2PO4）, the release of CO2 was very slow and the condition was highly con- trolled so that the ionization of HPAM was prevented initially. Furthermore, the hydrogen bonding interactions between HPAM and melamine embedded in solution previously also postponed the ionization of HPAM. As a result, the crosslinking between HPAM and Cr3＋ can be delayed for almost one month, completely meeting the requirements for deep water shut-off and profile control to enhance oil recovery.
基金Project(61471194)supported by the National Natural Science Foundation of ChinaProject(BK20140828)supported by the Natural Science Foundation of Jiangsu Province,ChinaProject supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education,China
文摘In order to improve the throughput of cognitive radio(CR), optimization of sensing time and cooperative user allocation for OR-rule cooperative spectrum sensing was investigated in a CR network that includes multiple users and one fusion center. The frame structure of cooperative spectrum sensing was divided into multiple transmission time slots and one sensing time slot consisting of local energy detection and cooperative overhead. An optimization problem was formulated to maximize the throughput of CR network, subject to the constraints of both false alarm probability and detection probability. A joint optimization algorithm of sensing time and number of users was proposed to solve this optimization problem with low time complexity. An allocation algorithm of cooperative users was proposed to preferentially allocate the users to the channels with high utilization probability. The simulation results show that the significant improvement on the throughput can be achieved through the proposed joint optimization and allocation algorithms.
基金the National Natural Science Foundation of China.
文摘A field experiment was conducted to study the combined effect of nutrient andpest managements on soil biomass phospholipid contents, functional biodiversity and substrateutilization patterns of soil microbial populations in hybrid rice cropping system. The mineral N, Pand K fertilizers (as urea, calcium superphosphate and KCl respectively) were incorporated at 100,25, and 100 kg ha^(-1), respectively, and the various pesticides were applied at the recommendedrates. The results of the experiment demonstrated a decline in the microbial abundance and soilmicrobial biomass phospholipid contents with the advancement of crop growth, and significant changesin substrate utilization pattern of soil microbial population studied were observed with differentmanagement practices and at different growth stages. The principal component analysis (PCA) usingall 95-carbon sources (BIOLOG plates) gave good differentiation among the treatments, indicatingthat they have different patterns of carbon utilization under different habitats. The data showedthat diversity in microbial community continuously changed with the progression in crop stage,particularly at physiological maturity (PM) stage that was evident from the utilization of differentcarbon sources at various crop stages.
基金Support by the National High Technology Research and Development Program of China(2012AA120802)the National Natural Science Foundation of China(61771186)+1 种基金the Postdoctoral Research Project of Heilongjiang Province(LBH-Q15121) the Undergraduate University Project of Young Scientist Creative Talent of Heilongjiang Province(UNPYSCT-2017125)
文摘The universality of the application of wireless sensor networks( WSN) makes more attention be paid on the security problem. Node authentication is not only the basis of network security,but also the premise of key management and secure routing protocol. Although the signature mechanism based on symmetric encryption is high in energy efficiency,it is vulnerable to be attacked and there is a time delay during authentication. Traditional public key encryption mechanism with improvement in security brings in complex algorithm and costs much time,which is not suitable for WSN. In this paper,a signature authentication mechanism,an optimized variant Bellare Namprempre Neven( OvBNN) is presented to quickly complete the authentication by mutual cooperation between nodes so as to make the nodes use the intermediate calculation results of their neighbor nodes directly.Simulation results show that the proposed mechanism is superior to traditional authentication mechanisms both in energy consumption and authentication time.
基金ACKNOWLEDGEMENT We gratefully acknowledge anonymous revie- wers who read drafts and made many helpful suggestions. This work was supported by the National Natural Science Foundation of China under Grant No. 61202079 the China Post- doctoral Science Foundation under Grant No. 2013M530526+2 种基金 the Foundation of Beijing En- gineering the Fundamental Research Funds for the Central Universities under Grant No. FRF-TP-13-015A and the Technology Centre for Convergence Networks and Ubiquitous Services.
文摘Internet of Things （IoT） refers to an infrastructure which enables the forms of com- munication and collaboration between people and things, and between things themselves. In order to improve its performance, we present a tradeoff between bandwidth and energy con- sumption in the loT in this paper. A service providing model is built to find the relation- ship between bandwidth and energy consump- tion using a cooperative differential game mo- del. The game solution is gotten in the condi- tion of grand coalition, feedback Nash equili- brium and intermediate coalitions and an allo- cation policy is obtain by Shapley theory. The results are shown as follows. Firstly, the per- formance of IoT decreases with the increasing of bandwidth cost or with the decreasing of en- ergy cost; secondly, all the nodes in the IoT com- posing a grand coalition can save bandwidth and energy consumption; thirdly, when the fac- tors of bandwidth cost and energy cost are eq- ual, the obtained number of provided services is an optimised value which is the trade-off between energy and bandwidth consumption.
