Introduction: To investigate the possible role of sentinel lymph node biopsy (SLNB) to upstage the N0 neck in patients with oral and oropharyngeal squamous cell carcinoma. Methods: Patients with T1-T2 oral and orophar...Introduction: To investigate the possible role of sentinel lymph node biopsy (SLNB) to upstage the N0 neck in patients with oral and oropharyngeal squamous cell carcinoma. Methods: Patients with T1-T2 oral and oropharyngeal squamous cell carcinoma accessible to injection and staged N0 into the neck by palaption and CTscan were enrolled in the study. All patients underwent regular follow-up to identify possible recurrence. Results: A sentine lymph node biopsy was performed by 21 consecutive patients. 4 of the 21 patients were upstaged by SNLB. There was a mean follow-up of 31 months. Two patients developed subsequent disease after having been staging by SLNB, respectively negative in one case and positive in the other case. Tumor site, the staging of the primary tumor, presence of ulceration, tumor thickness were the same in the upstaged initially N0 patients. Conclusions: Sentinel lymph node biopsy can be used to upstage the N0 neck patients in perhaps well defined patients.展开更多
As each cluster head(CH)sensor node is used to aggregate,fuse,and forward data from different sensor nodes in an underwater acoustic sensor network(UASN),guaranteeing the data security in a CH is very critical.In this...As each cluster head(CH)sensor node is used to aggregate,fuse,and forward data from different sensor nodes in an underwater acoustic sensor network(UASN),guaranteeing the data security in a CH is very critical.In this paper,a cooperative security monitoring mechanism aided by multiple slave cluster heads(SCHs)is proposed to keep track of the data security of a CH.By designing a low complexity“equilateral triangle algorithm(ETA)”,the optimal SCHs(named as ETA-based multiple SCHs)are selected from the candidate SCHs so as to improve the dispersion and coverage of SCHs and achieve largescale data security monitoring.In addition,by analyzing the entire monitoring process,the close form expression of the probability of the failure attack identification for the SCHs with respect to the probability of attack launched by ordinary nodes is deduced.The simulation results show that the proposed optimal ETA-based multiple SCH cooperation scheme has lower probability of the failure attack identification than that of the existing schemes.In addition,the numerical simulation results are consistent with the theoretical analysis results,thus verifying the effectiveness of the proposed scheme.展开更多
随着现代通信和信息技术的飞速发展,智能交通系统(Intelligent Transportation System,ITS)逐渐成为热门研究领域,车载自组网(Vehicular Ad Hoc Network,VANET)作为其关键技术,在实时道路信息共享和车辆间通信中起重要作用.然而,现有VA...随着现代通信和信息技术的飞速发展,智能交通系统(Intelligent Transportation System,ITS)逐渐成为热门研究领域,车载自组网(Vehicular Ad Hoc Network,VANET)作为其关键技术,在实时道路信息共享和车辆间通信中起重要作用.然而,现有VANET分簇算法仍存在簇稳定性低、分簇开销大等问题.为解决这些问题,本文提出了一种端云协同的VANET分簇算法,在端云协同阶段,车辆通过路边单元(Road Side Unit,RSU)将自身特征数据上传至云,云侧根据特征变化,对车辆进行动态稳定性分类.稳定的端节点具有更高的可靠性和更长的连接持续时间.在端端协同阶段,考虑了稳定节点的相对移动性和覆盖节点数量等因素,进行簇头选举,简化簇头选举过程,提高了簇的稳定性.此外,针对控制开销大的问题,本文提出了一种邻居发现和更新机制,限制HELLO消息的转发操作,降低开销并优化资源使用.实验结果表明:本文提出的算法在簇稳定性、簇数量及分簇开销等关键性能指标上均优于基线算法,展示了其在实际交通场景中的应用潜力.展开更多
To satisfy the requirements of independent navigation in low cost multiple robots,a navigation frame of masterslave robots with only one master robot is introduced briefly.A range-only navigation algorithm for slave r...To satisfy the requirements of independent navigation in low cost multiple robots,a navigation frame of masterslave robots with only one master robot is introduced briefly.A range-only navigation algorithm for slave robots of low cost is presented for the navigation in unknown current.This algorithm only needs a master robot.The master is just a single mobile node which has high navigation performance.Observability of this master-salve system is theoretically analyzed.The conditions of slave robot trajectory under which observability is guaranteed are evaluated by a slave robot in real-time.The slave takes appropriate action to control its heading to achieve observability if observability is lost on the current trajectory.The navigation algorithm is implemented by a standard extended Kalman filter,and it is able to acquire accurate estimation of robot's position.The simulation results show its effectiveness of the proposed algorithm.展开更多
We describe a novel technique for sentinel lymph node mapping and biopsy of a primary cutaneous malignant melanoma in the medial portion of the external auditory canal. The approach is illustrated through a case repor...We describe a novel technique for sentinel lymph node mapping and biopsy of a primary cutaneous malignant melanoma in the medial portion of the external auditory canal. The approach is illustrated through a case report and technical description of a procedure performed under general anesthesia on a 19-year-old female patient. Due to the hidden and sensitive location of the primary tumor in the medial external auditory canal, the lymphoscintigraphy injection had to be performed by the surgeon immediately prior to the resection of her c T2 a N0M0 lesion. Final pathology revealed clear margins at the primary site resection and 2 intraparotid sentinel lymph nodes with microscopic foci of metastatic malignant melanoma, which led to further surgical management. A completion left parotidectomy and neck dissection yielded no additional metastatic disease in the fifty-five nodes that were evaluated. Using this technique, sentinel lymph node mapping and biopsy accurately predicted the highest risk lymph nodes for the primary lesion of the medial portion of the external auditory canal.展开更多
Mobile Ad hoc Network (MANET) is a significant concept of wireless networks which comprises of thousands of nodes that are mobile as well as autonomous and they do not requires any existing network infrastructure. The...Mobile Ad hoc Network (MANET) is a significant concept of wireless networks which comprises of thousands of nodes that are mobile as well as autonomous and they do not requires any existing network infrastructure. The autonomous nodes can freely and randomly move within the network which can create temporary dynamic network and these networks can change their topology frequently. The security is the primary issue in MANET which degrades the network performance significantly. In this paper, cluster based malicious node detection methodology is proposed to detect and remove the malicious nodes. Each node within the cluster gets the cluster key from the cluster head and this key is used for the data transaction between cluster head and node. The cluster head checks this key for every data transaction from node and match with their cluster table. If match is valid, and then only it will recognize that this node is belongs to this cluster, otherwise it is decided as malicious node. This paper also discusses the detection of link failure due to the presence of malicious node by determining the gain of each link in the network. The performance of the proposed method is analyzed using packet delivery ratio, network life time, and throughput and energy consumption. The proposed malicious node detection system is compared with the conventional techniques as OEERP (Optimized energy efficient routing protocol), LEACH (Low energy adaptive clustering hierarchy), DRINA (Data routing for In-network aggregation) and BCDCP (Base station controlled dynamic clustering protocol).展开更多
Background: Management of N0 neck in patients with head and neck squamous cell carcinoma (HNSCC) remains a subject of continued debate. Prognostic biomarkers might provide useful information for treatment selection an...Background: Management of N0 neck in patients with head and neck squamous cell carcinoma (HNSCC) remains a subject of continued debate. Prognostic biomarkers might provide useful information for treatment selection and adjustment. Objective: To evaluate the prognostic relevance of VEGF-A and Ki-67 expression to types of neck management. Methods: This prospective study included 140 patients with HNSCC. Tumor expression of VEGF-A and Ki-67 was measured by immunohistochemistry. Based on tumor size and site criteria, 88 patients with N0 neck were categorized as high, intermediate and low risk of subclinical neck diseases and accordingly treated by elective neck dissection (END), irradiation (ENI) and observation. Adjuvant treatment was given to tumor with close or positive margins. A multivariate Cox regression model was used to identify prognostic factors. Impact of biomarker expression, treatment type and risk category on disease-specific survival (DSS) in the setting of N0 neck were evaluated by Kaplan-Meier survival and adjusted hazard ratio (HR). Results: Coexpression of VEGF-A and Ki-67 (HR = 2.351, p = 0.021) and positive node (HR = 2.301, p = 0.009) were independent prognostic factors for HNSCC. In the setting of N0 neck, marker coexpression has an HR of 4.97 (p = 0.004) independent of treatment modalities (p = 0.069) and risk categories (p = 0.971). Alternatively, neither marker expression was predictive of a better treatment outcome for END compared to ENI, as suggested by the odds of patients being survived 15.4 times greater (p = 0.01) and the 5-year DSS rates of 85.1% versus 44.7% (p = 0.008). Conclusion: Coexpression of VEGF-A and Ki-67 is a suggestion of tumor microinvasiveness in addition to risk of lymph node metastasis and may indicate the need of adjuvant treatment despite negative tumor margins. Neither marker expression serves an indicator for the selection of END over ENI in neck management.展开更多
文摘Introduction: To investigate the possible role of sentinel lymph node biopsy (SLNB) to upstage the N0 neck in patients with oral and oropharyngeal squamous cell carcinoma. Methods: Patients with T1-T2 oral and oropharyngeal squamous cell carcinoma accessible to injection and staged N0 into the neck by palaption and CTscan were enrolled in the study. All patients underwent regular follow-up to identify possible recurrence. Results: A sentine lymph node biopsy was performed by 21 consecutive patients. 4 of the 21 patients were upstaged by SNLB. There was a mean follow-up of 31 months. Two patients developed subsequent disease after having been staging by SLNB, respectively negative in one case and positive in the other case. Tumor site, the staging of the primary tumor, presence of ulceration, tumor thickness were the same in the upstaged initially N0 patients. Conclusions: Sentinel lymph node biopsy can be used to upstage the N0 neck patients in perhaps well defined patients.
基金supported in part by the Joint Fund of Science and Technology Department of Liaoning Province and State Key Laboratory of Robotics,China under Grant 2021-KF-22-08in part by the Basic Research Program of Science and Technology of Shenzhen,China under Grant JCYJ20190809161805508in part by the National Natural Science Foundation of China under Grant 62271423 and Grant 41976178.
文摘As each cluster head(CH)sensor node is used to aggregate,fuse,and forward data from different sensor nodes in an underwater acoustic sensor network(UASN),guaranteeing the data security in a CH is very critical.In this paper,a cooperative security monitoring mechanism aided by multiple slave cluster heads(SCHs)is proposed to keep track of the data security of a CH.By designing a low complexity“equilateral triangle algorithm(ETA)”,the optimal SCHs(named as ETA-based multiple SCHs)are selected from the candidate SCHs so as to improve the dispersion and coverage of SCHs and achieve largescale data security monitoring.In addition,by analyzing the entire monitoring process,the close form expression of the probability of the failure attack identification for the SCHs with respect to the probability of attack launched by ordinary nodes is deduced.The simulation results show that the proposed optimal ETA-based multiple SCH cooperation scheme has lower probability of the failure attack identification than that of the existing schemes.In addition,the numerical simulation results are consistent with the theoretical analysis results,thus verifying the effectiveness of the proposed scheme.
文摘随着现代通信和信息技术的飞速发展,智能交通系统(Intelligent Transportation System,ITS)逐渐成为热门研究领域,车载自组网(Vehicular Ad Hoc Network,VANET)作为其关键技术,在实时道路信息共享和车辆间通信中起重要作用.然而,现有VANET分簇算法仍存在簇稳定性低、分簇开销大等问题.为解决这些问题,本文提出了一种端云协同的VANET分簇算法,在端云协同阶段,车辆通过路边单元(Road Side Unit,RSU)将自身特征数据上传至云,云侧根据特征变化,对车辆进行动态稳定性分类.稳定的端节点具有更高的可靠性和更长的连接持续时间.在端端协同阶段,考虑了稳定节点的相对移动性和覆盖节点数量等因素,进行簇头选举,简化簇头选举过程,提高了簇的稳定性.此外,针对控制开销大的问题,本文提出了一种邻居发现和更新机制,限制HELLO消息的转发操作,降低开销并优化资源使用.实验结果表明:本文提出的算法在簇稳定性、簇数量及分簇开销等关键性能指标上均优于基线算法,展示了其在实际交通场景中的应用潜力.
基金Natural Science Foundation of Liaoning Province(20102236)
文摘To satisfy the requirements of independent navigation in low cost multiple robots,a navigation frame of masterslave robots with only one master robot is introduced briefly.A range-only navigation algorithm for slave robots of low cost is presented for the navigation in unknown current.This algorithm only needs a master robot.The master is just a single mobile node which has high navigation performance.Observability of this master-salve system is theoretically analyzed.The conditions of slave robot trajectory under which observability is guaranteed are evaluated by a slave robot in real-time.The slave takes appropriate action to control its heading to achieve observability if observability is lost on the current trajectory.The navigation algorithm is implemented by a standard extended Kalman filter,and it is able to acquire accurate estimation of robot's position.The simulation results show its effectiveness of the proposed algorithm.
文摘We describe a novel technique for sentinel lymph node mapping and biopsy of a primary cutaneous malignant melanoma in the medial portion of the external auditory canal. The approach is illustrated through a case report and technical description of a procedure performed under general anesthesia on a 19-year-old female patient. Due to the hidden and sensitive location of the primary tumor in the medial external auditory canal, the lymphoscintigraphy injection had to be performed by the surgeon immediately prior to the resection of her c T2 a N0M0 lesion. Final pathology revealed clear margins at the primary site resection and 2 intraparotid sentinel lymph nodes with microscopic foci of metastatic malignant melanoma, which led to further surgical management. A completion left parotidectomy and neck dissection yielded no additional metastatic disease in the fifty-five nodes that were evaluated. Using this technique, sentinel lymph node mapping and biopsy accurately predicted the highest risk lymph nodes for the primary lesion of the medial portion of the external auditory canal.
文摘Mobile Ad hoc Network (MANET) is a significant concept of wireless networks which comprises of thousands of nodes that are mobile as well as autonomous and they do not requires any existing network infrastructure. The autonomous nodes can freely and randomly move within the network which can create temporary dynamic network and these networks can change their topology frequently. The security is the primary issue in MANET which degrades the network performance significantly. In this paper, cluster based malicious node detection methodology is proposed to detect and remove the malicious nodes. Each node within the cluster gets the cluster key from the cluster head and this key is used for the data transaction between cluster head and node. The cluster head checks this key for every data transaction from node and match with their cluster table. If match is valid, and then only it will recognize that this node is belongs to this cluster, otherwise it is decided as malicious node. This paper also discusses the detection of link failure due to the presence of malicious node by determining the gain of each link in the network. The performance of the proposed method is analyzed using packet delivery ratio, network life time, and throughput and energy consumption. The proposed malicious node detection system is compared with the conventional techniques as OEERP (Optimized energy efficient routing protocol), LEACH (Low energy adaptive clustering hierarchy), DRINA (Data routing for In-network aggregation) and BCDCP (Base station controlled dynamic clustering protocol).
文摘Background: Management of N0 neck in patients with head and neck squamous cell carcinoma (HNSCC) remains a subject of continued debate. Prognostic biomarkers might provide useful information for treatment selection and adjustment. Objective: To evaluate the prognostic relevance of VEGF-A and Ki-67 expression to types of neck management. Methods: This prospective study included 140 patients with HNSCC. Tumor expression of VEGF-A and Ki-67 was measured by immunohistochemistry. Based on tumor size and site criteria, 88 patients with N0 neck were categorized as high, intermediate and low risk of subclinical neck diseases and accordingly treated by elective neck dissection (END), irradiation (ENI) and observation. Adjuvant treatment was given to tumor with close or positive margins. A multivariate Cox regression model was used to identify prognostic factors. Impact of biomarker expression, treatment type and risk category on disease-specific survival (DSS) in the setting of N0 neck were evaluated by Kaplan-Meier survival and adjusted hazard ratio (HR). Results: Coexpression of VEGF-A and Ki-67 (HR = 2.351, p = 0.021) and positive node (HR = 2.301, p = 0.009) were independent prognostic factors for HNSCC. In the setting of N0 neck, marker coexpression has an HR of 4.97 (p = 0.004) independent of treatment modalities (p = 0.069) and risk categories (p = 0.971). Alternatively, neither marker expression was predictive of a better treatment outcome for END compared to ENI, as suggested by the odds of patients being survived 15.4 times greater (p = 0.01) and the 5-year DSS rates of 85.1% versus 44.7% (p = 0.008). Conclusion: Coexpression of VEGF-A and Ki-67 is a suggestion of tumor microinvasiveness in addition to risk of lymph node metastasis and may indicate the need of adjuvant treatment despite negative tumor margins. Neither marker expression serves an indicator for the selection of END over ENI in neck management.