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Pelvic Organs Prolapse in Low-Resources Countries: Epidemiology, Risk Factors, Quality of Life. Narrative Review
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作者 Eloge Ilunga-Mbaya Dénis Mukwege +3 位作者 Prosper Lukusa Tshilobo Kenny Raha Maroyi Rahma Rashid Tozin Dieudonné Sengeyi Mushengezi 《Open Journal of Urology》 2023年第7期238-250,共13页
Objective: Pelvic organ prolapse is an emerging public health problem affecting adult women of all ages with a negative impact on social, physical well-being, and psychological. Its presents several challenges in coun... Objective: Pelvic organ prolapse is an emerging public health problem affecting adult women of all ages with a negative impact on social, physical well-being, and psychological. Its presents several challenges in countries with low resources. This literature review aims to examine POP in its epidemiological aspects, risk factors, and staging by taking up the challenges associated with low-resource settings and identifying some avenues for future research. Methods: We searched the PubMed, Google Scholar, and Scopus databases. The other studies were identified by checking the secondary references in the original citation. We have collected studies on adult women published in English for the last 30 years. In total, 71 articles were read. We excluded studies from all newspaper articles, Studies presenting co-morbidities (fistulas, cervical cancer, pregnancy), those evaluating treatment, letters, comments, case reports, practice guidelines, news, historical articles, legal cases, published erratum, and congresses. Results: 16 studies examining the epidemiology have been identified with 11 in countries defined by the World Bank as limited or intermediate resources. 18 on risk factors whose 10 in countries with limited or intermediate resources, 10 on staging and 27 on physiopathology. Conclusion: POP affects the young more in low-resource settings. Its prevalence remains underestimated for several reasons. Several risk factors found are the same as those of women in countries with a high standard of living. However, there are some specific risk factors for these resource-limited settings. 展开更多
关键词 EPIDEMIOLOGY Low Resources-Countries Pelvic organs Prolapse risk Factors
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Multidrug resistant organism infections in patients with COVID-19:risk factors and outcomes
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作者 Yang Kun Bao-Qi Zeng +8 位作者 Qing-Qing Yang Meng Zhang Yun Lu Wen-Jing Li Su-Yu Gao Xuan-Xuan Wang Wen Hu Hong Cheng Feng Sun 《Medical Data Mining》 2023年第2期1-6,共6页
Background:Coronavirus disease 2019(COVID-19)has now spread to most countries and regions of the world.Risk factors associated with multi-drug resistant organism(MDRO)infections in patients with COVID-19 have not been... Background:Coronavirus disease 2019(COVID-19)has now spread to most countries and regions of the world.Risk factors associated with multi-drug resistant organism(MDRO)infections in patients with COVID-19 have not been well studied yet.In the present study,we aimed to identify the risk factors associated with the MDRO infections and their impact on in-hospital mortality of COVID-19 patients.Methods:This retrospective cohort study was conducted between December 2019 and April 2020 at two tertiary hospitals in Wuhan,China.Data of cases were collected through electronic medical records system.This study was focused on cases with bacterial culture records.Risk factors and outcomes associated with MDRO infections were analyzed using logistic regression model.Results:Of the 2891 patients,370 patients have bacterial culture results,and MDROs were isolated in 38 patients.Respiratory tract infections(67.3%)were the most common hospital acquired infections.Variables independently associated with MDRO infections were dyspnea at admission(odds ratio(OR)4.74;95%confidence interval(CI)2.06-10.88;P<0.001),intensive care unit(ICU)admission(OR 5.02;95%CI 1.99-12.63;P<0.01),and invasive mechanical ventilation(OR 5.13;95%CI 2.15-12.27;P<0.001),adjusted for age and gender.MDROs infection was also a significant risk factor of death for the patients,adjusted for age,gender,severity of illness,ICU admission and mechanical ventilation(OR 1.12,95%CI:0.43-2.96,P=0.817).Conclusion:In our study,dyspnea at admission,ICU admission and invasive mechanical ventilation were associated with the presence of MDRO infections,and clinicians should be alert in MDRO infections in COVID-19 hospitalized patients. 展开更多
关键词 COVID-19 multi-drug resistant organism INFECTION risk factor SARS-CoV-2
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Automatic delineation of organs at risk in non-small cell lung cancer radiotherapy based on deep learning networks 被引量:1
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作者 Anning Yang Na Lu +5 位作者 Huayong Jiang Diandian Chen Yanjun Yu Yadi Wang Qiusheng Wang Fuli Zhang 《Oncology and Translational Medicine》 CAS 2022年第2期83-88,共6页
Objective To introduce an end-to-end automatic segmentation method for organs at risk(OARs)in chest computed tomography(CT)images based on dense connection deep learning and to provide an accurate auto-segmentation mo... Objective To introduce an end-to-end automatic segmentation method for organs at risk(OARs)in chest computed tomography(CT)images based on dense connection deep learning and to provide an accurate auto-segmentation model to reduce the workload on radiation oncologists.Methods CT images of 36 lung cancer cases were included in this study.Of these,27 cases were randomly selected as the training set,six cases as the validation set,and nine cases as the testing set.The left and right lungs,cord,and heart were auto-segmented,and the training time was set to approximately 5 h.The testing set was evaluated using geometric metrics including the Dice similarity coefficient(DSC),95%Hausdorff distance(HD95),and average surface distance(ASD).Thereafter,two sets of treatment plans were optimized based on manually contoured OARs and automatically contoured OARs,respectively.Dosimetric parameters including Dmax and Vx of the OARs were obtained and compared.Results The proposed model was superior to U-Net in terms of the DSC,HD95,and ASD,although there was no significant difference in the segmentation results yielded by both networks(P>0.05).Compared to manual segmentation,auto-segmentation significantly reduced the segmentation time by nearly 40.7%(P<0.05).Moreover,the differences in dose-volume parameters between the two sets of plans were not statistically significant(P>0.05).Conclusion The bilateral lung,cord,and heart could be accurately delineated using the DenseNet-based deep learning method.Thus,feature map reuse can be a novel approach to medical image auto-segmentation. 展开更多
关键词 non-small cell lung cancer organs at risk medical image segmentation deep learning DenseNet
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Dosimetric benefit to organs at risk following margin reductions in nasopharyngeal carcinoma treated with intensity-modulated radiation therapy 被引量:3
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作者 Yan-Ping Mao Wen-Jing Yin +7 位作者 Rui Guo Guang-Shun Zhang Jian-Lan Fang Feng Chi Zhen-Yu Qi Meng-Zhong Liu Jun Ma Ying Sun 《Chinese Journal of Cancer》 SCIE CAS CSCD 2015年第5期189-197,共9页
Introduction:It is important to decrease the radiation exposure of normal tissue in intensity-modulated radiation therapy(IMRT).Minimizing planning target volume(PTV) margins with more precise target localization tech... Introduction:It is important to decrease the radiation exposure of normal tissue in intensity-modulated radiation therapy(IMRT).Minimizing planning target volume(PTV) margins with more precise target localization techniques can achieve this goal.This study aimed to quantify the extent to which organs at risk(OARs) are spared when using reduced margins in the treatment of nasopharyngeal carcinoma(NPC).Methods:Two IMRT plans were regenerated for 40 patients with NPC based on two PTV margins,which were reduced or unchanged following cone beam computed tomography online correction.The reduced-margin plan was optimized based on maximal dose reduction to OARs without compromising target coverage.Dosimetric comparisons were evaluated in terms of target coverage and OAR sparing.Results:Improvements in target coverage occurred with margin reduction,and significant improvements in dosimetric parameters were observed for all OARs(P<0.05) except for the right optic nerve,chiasm,and lens.Doses to OARs decreased at a rate of 1.5%to 7.7%.Sparing of the left parotid and right parotid,where the mean dose(D_(mean)) decreased at a rate of 7.1%and 7.7%,respectively,was greater than the sparing of other OARs.Conclusions:Significant improvements in OAR sparing were observed with margin reduction,in addition to improvement in target coverage.The parotids benefited most from the online imaging-guided approach. 展开更多
关键词 放射治疗 大剂量 保证金 鼻咽癌 风险 放疗 机关 效益
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Towards automated organs at risk and target volumes contouring: Defining precision radiation therapy in the modern era 被引量:1
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作者 Dakai Jin Dazhou Guo +2 位作者 Jia Ge Xianghua Ye Le Lu 《Journal of the National Cancer Center》 2022年第4期306-313,共8页
Precision radiotherapy is a critical and indispensable cancer treatment means in the modern clinical workflow with the goal of achieving“quality-up and cost-down”in patient care.The challenge of this therapy lies in... Precision radiotherapy is a critical and indispensable cancer treatment means in the modern clinical workflow with the goal of achieving“quality-up and cost-down”in patient care.The challenge of this therapy lies in developing computerized clinical-assistant solutions with precision,automation,and reproducibility built-in to deliver it at scale.In this work,we provide a comprehensive yet ongoing,incomplete survey of and discussions on the recent progress of utilizing advanced deep learning,semantic organ parsing,multimodal imaging fusion,neural architecture search and medical image analytical techniques to address four corner-stone problems or sub-problems required by all precision radiotherapy workflows,namely,organs at risk(OARs)segmentation,gross tumor volume(GTV)segmentation,metastasized lymph node(LN)detection,and clinical tumor volume(CTV)segmentation.Without loss of generality,we mainly focus on using esophageal and head-and-neck cancers as examples,but the methods can be extrapolated to other types of cancers.High-precision,automated and highly reproducible OAR/GTV/LN/CTV auto-delineation techniques have demonstrated their effectiveness in reducing the inter-practitioner variabilities and the time cost to permit rapid treatment planning and adaptive replanning for the benefit of patients.Through the presentation of the achievements and limitations of these techniques in this review,we hope to encourage more collective multidisciplinary precision radiotherapy workflows to transpire. 展开更多
关键词 organs at risk Target tumor volume Radiation therapy
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The Effect of Absorbed Dose to Organs at Risk Following Craniospinal Irradiation Using Different Radiotherapy Techniques
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作者 Hadeer A. Shahin Ehab M. Attalla +3 位作者 H. S. Abou-Elenien Hussein Elsayed Ibrahim Bashter Marwa A. Suliman 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2020年第2期73-85,共13页
Introduction: In medulloblastoma patients craniospinal irradiation is an important element the treatment. Our study aimed to evaluate the effect of absorbed dose to organs at risk using the hybrid intensity-modulated ... Introduction: In medulloblastoma patients craniospinal irradiation is an important element the treatment. Our study aimed to evaluate the effect of absorbed dose to organs at risk using the hybrid intensity-modulated radiation therapy (IMRT) versus three-dimensional conformal radiotherapy (3DCRT) for craniospinal irradiation (CSI) in average risk medulloblastoma patients. Materials and Methods: In this study, thirteen medulloblastoma patients were included. The prescribed total dose to the planning target volume (PTV) was 23, 40 Gy in 13 fractions. Two radiotherapy techniques, three dimensional conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (IMRT) were used to treat these patients. The coverage of the Target was evaluated using the D mean, D95%, D2%, D98% and V95%. Other parameters were also compared such as Integral dose (ID), Homogeneity index (HI) and doses to the organs at risk (OARs). Results: There was no significant difference in the mean dose received by the PTV-Brain or the dose received by 95% and 98% of PTV volume using the two techniques. For PTV-Spine, the percentage volume receiving 95% of the total dose increased significantly in the hybrid IMRT technique compared to the conformal technique. So, hybrid IMRT plan achieved the best coverage for PTV spine. Lower dose for OAR was delivered by 3DCRT, except the heart and thyroid, hybrid IMRT achieved better sparing. All plans resulted in the same dose homogeneity index (DHI) for PTV-Brain. For PTV-Spine, hybrid IMRT technique achieved better dose homogeneity compared to 3DCRT technique (1.09 vs. 1.12;p > 0.05). Conclusions: hybrid IMRT technique can be realized on conformal technique because it achieved better dose coverage for the (PTV) and organ at risk (OAR). 3DCRT reduced mean dose to most OARS, except the heart and thyroid. Therefore, the hybrid IMRT technique may be a CSI treatment alternative to 3DCRT. 展开更多
关键词 CRANIOSPINAL Irradiation Three-Dimensional Conformal RADIOTHERAPY INTENSITY-MODULatED Radiation Therapy MEDULLOBLASTOMA organs at risk HOMOGENEITY Index
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Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake,North China:Concentrations,sources profiles and potential risk 被引量:43
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作者 Guocheng Hu Xiaojun Luo +6 位作者 Fengchao Li Jiayin Dai Jianyang Guo Shejun Chen Cao Hong Bixian Mai Muqi Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第2期176-183,共8页
Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflow... Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river (Fuhe River) in North China. Total concentrations of OCPs, PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng]g, 2.3 to 197.8 ng/g, and 101.3 to 6360.5 ng]g, respectively. The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake. For hexachlorocyclohexane (HCHs) and dichlorodiphenytrich/oroethanes (DDTs), α-HCH and p,p'-DDT were predominant isomers; while for PCBs, PCB 28/31, PCB 40/103, PCB 60, PCB 101, and PCB 118 were predominant congeners. Possible sources derived from historical usage for OCPs and incomplete combustion fuel, wood, and coal and exhaustion of boats or cars for PAHs. Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact. 展开更多
关键词 persistent organic pollutants CONCENTRatIONS profiles risk assessment Baiyangdian Lake
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Genotoxicity evaluation and a primary risk assessment of organic pollutants in the drinking water sources of Nanjing, China 被引量:6
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作者 LI Yi-qiang WU Yu-lin +1 位作者 CHEN Yuan-gao KONG Zhi-ming 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第5期983-988,共6页
An increasing number of industrial, agricultural, and commercial chemicals in the aquatic environment leads to various deleterious effects on organisms, which is becoming an increasingly serious problem in China. In t... An increasing number of industrial, agricultural, and commercial chemicals in the aquatic environment leads to various deleterious effects on organisms, which is becoming an increasingly serious problem in China. In this study, the comet assay was conducted to investigate the genotoxicity to human body caused by organic concentrates in the drinking water sources of Nanjing City from Yangtze River of China, and health and ecology risk due to expose to these organic pollutants were evaluated with the multimedia environmental assessment system (MEAS). For all the water samples, they were collected from four different locations in the drinking water sourcr samples, es of Nanjing City. The results of the comet assay showed that all the organic concentrates from the water samples could induce different levels DNA damages on human peripheral blood lymphocytes, and a statistically significant difference (p〈0.01) was observed compared with the solvent control, which demonstrated the genotoxicity was in existence. According to the ambient severity (AS) of individual compound, we had sorted out the main organic pollutants in the drinking water source of the four waterworks, and the results showed that there was some potential hazard to human body for all the source water, namely the total ambient severity (TAS) of health for each water source was more than 1. However, the TAS of ecology for each water source was less than 1, which indicated that it was safe to ecology. The results of this investigation demonstrate the application of the comet assay and the MEAS in aquatic environmental monitoring studies, and the comet assay found to be fast, sensitive, and suitable for genotoxicity monitoring programs of drinking water source. 展开更多
关键词 GENOTOXICITY comet assay risk assessment organic pollutants drinking water sources Nanjing City
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Human Health Risk Assessment Model of Organic Pollution in Groundwater:Shijiazhuang Industrial Zone 被引量:4
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作者 YANG Mei FEI Yuhong +1 位作者 JU Yiwen LI Huaqi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2011年第6期1508-1517,共10页
In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residua... In this study, a risk-based management model is developed and applied to an industrial zone. The models proposed by the United States Environmental Protection Agency and Han Bing have been improved by adding a residual ratio of volatile organic compounds (VOC) after boiling and deleting the related parameters in half-life. Using this improved model, an integrated process was used to assess human health risk level in the study area. Compared with water quality analysis, the results highlight the importance of applying an integrated approach for decision making on risk levels and water protection. The results of this study demonstrated that: (1) Compared with these permissible level standards in China (GB 3838-2002) and National Primary Drinking Water Regulations of the United States, the residents' daily life had not been affected by the groundwater in this area (except for relative bad water quality of HB3-4 and HB3-6); (2) The typical detected organic contaminants of all groundwater samples were chloroform, carbon tetrachloride, trichloroethylene and tetrachloroethene, and the pollution sources were mainly industrial sources by preliminary investigations; (3) As for groundwater, the non-carcinogenic risk values of all samples do not exceed the permissible level of 1.0 and the carcinogenic risk values are relatively lower than the permissible level of 1.00E-06 to 1.00E-04; (4) Drinking water pathway of trichloroethylene and tetrachloroethylene mainly contribute to increasing the health risk of residents' in study areas; (5) In terms of non-carcinogenic risk and carcinogenic risk, the health risk order for drinking water pathway and dermal contact pathway was: drinking water pathway 〉 dermal contact pathway. 展开更多
关键词 groundwater pollution organic contaminants residual rate assessment model human health risk
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Preoperative risk factor analysis in orthotopic liver transplantation with pretransplant artificial liver support therapy 被引量:8
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作者 Jin-Zhong Yuan Qi-Fa Ye Ling-Ling Zhao Ying-Zi Ming Hong Sun Shai-Hong Zhu Zu-Fa Huang Min-Min Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第31期5055-5059,共5页
AIM: To assess the value of pre-transplant artificial liver support in reducing the pre-operative risk factors relating to early mortality after orthotopic liver transplantation (OLT). METHODS: Fifty adult patient... AIM: To assess the value of pre-transplant artificial liver support in reducing the pre-operative risk factors relating to early mortality after orthotopic liver transplantation (OLT). METHODS: Fifty adult patients with various stages and various etiologies undergoing OLT procedures were treated with molecular adsorbent recycling system (MARS) as preoperative liver support therapy. The study included two parts, the first one is to evaluate the medical effectiveness of single MARS treatment with some clinical and laboratory parameters, which were supposed to be the therapeutical pre-transplant risk factors, the second part is to study the patients undergoing OLT using the regression analysis on preoperative risk factors relating to early mortality (30 d) after OLT. RESULTS: In the 50 patients, the statistically significant improvement in the biochemical parameters was observed (pre-treatment and post-treatment). Eight patients avoided the scheduled Ltx due to significant relief of clinical condition or recovery of failing liver function, 8 patients died, 34 patients were successfully bridged to Ltx, the immediate outcome of this 34 patients within 30d observation was: 28 kept alive and 6 patients died. CONCLUSION: Pre-operative SOFA, level of creatinine, INR, TNF-α, IL-10 are the main preoperative risk factors that cause early death after operation, MARS treatment before transplantion can relieve these factors significantly. 展开更多
关键词 Liver transplantation Artificial liver Sequential Organ Failure Assessment risk factors analysis
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Prevalence and risk factors of organ failure in patients with severe acute pancreatitis 被引量:8
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作者 Xiao-yan Li Xiao-bo Wang +1 位作者 Xiu-feng Liu Shu-gui Li 《World Journal of Emergency Medicine》 SCIE CAS 2010年第3期201-204,共4页
BACKGROUND: This study was undertaken to determine the prevalence of organ failure and its risk factors in patients with severe acute pancreatitis (SAP) .METHODS: A retrospective analysis was made of 186 patients ... BACKGROUND: This study was undertaken to determine the prevalence of organ failure and its risk factors in patients with severe acute pancreatitis (SAP) .METHODS: A retrospective analysis was made of 186 patients with SAP who were had been hospitalized in the intensive care unit of Jinzhong First People’s Hospital between March 2000 and October 2009. The patients met the diagnostic criteria of SAP set by the Surgical Society of the Chinese Medical Association in 2006. The variables collected included age, gender, etiology of SAP, the number of comorbidit, APACHEII score, contrast-enhanced CT (CECT) pancreatic necrosis, CT severity index (CTSI) , abdominal compartment syndrome (ACS) , the number of organ failure, and the number of death. The prevalence and mortality of organ failure were calculated. The variables were analyzed by unconditional multivariate logistic regression to determine the independent risk factors for organ failure in SAP.RESULTS: Of 186 patients, 96 had organ failure. In the 96 patients, 47 died. There was a significant association among the prevalence of organ failure and age, the number of comorbidity, APACHEII score, CECT pancreatic necrosis, CTSI, and ACS. An increase in age, the number of comorbidity, APACHEII score, CECT pancreatic necrosis were correlated with increased number of organ failure. Age, the number of comorbidity, APACHEII score, CECT pancreatic necrosis, CTSI and ACS were assessed by unconditional multivariate logistic regression.CONCLUSIONS: Organ failure occurred in 51.6% of the 186 patients with SAP. The mortality of SAP with organ failure was 49.0%. Age, the number of comorbidity, APACHEII score, CECT pancreatic necrosis, CTSI and ACS are independent risk factors of organ failure. 展开更多
关键词 Severe acute pancreatitis Organ failure PREVALENCE risk factor Age COMORBIDITY APACHE Pancreatic necrosis Abdominal compartment syndrome
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Network analysis using organizational risk analyzer 被引量:2
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作者 Chen, Xiaodong Li, Jianfeng Huang, Yanbo 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期104-108,共5页
The tool system of the organizational risk analyzer (ORA) to study the network of East Turkistan terrorists is selected. The model of the relationships among its personnel, knowledge, resources and task entities is re... The tool system of the organizational risk analyzer (ORA) to study the network of East Turkistan terrorists is selected. The model of the relationships among its personnel, knowledge, resources and task entities is represented by the meta-matrix in ORA, with which to analyze the risks and vulnerabilities of organizational structure quantitatively, and obtain the last vulnerabilities and risks of the organization. Case study in this system shows that it should be a shortcut to destroy effectively the network of terrorists by recognizing the caucus persons of the terrorism organization for the first and eliminating them when strikes the terror organization. It is vital to ensure effective use of the resources and control the risks of terrorist attacks. 展开更多
关键词 dynamic network analysis meta-matrix organization risk
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Lower limit of thermal maturity for the carbonization of organic matter in marine shale and its exploration risk 被引量:4
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作者 WANG Yuman LI Xinjing +8 位作者 CHEN Bo WU Wei DONG Dazhong ZHANG Jian HAN Jing MA Jie DAI Bing WANG Hao JIANG Shan 《Petroleum Exploration and Development》 2018年第3期402-411,共10页
Based on the drilling data of the Silurian Longmaxi Formation in the Sichuan Basin and periphery, SW China, the Ro lower limits and essential features of the carbonization of organic matter in over-high maturity marin... Based on the drilling data of the Silurian Longmaxi Formation in the Sichuan Basin and periphery, SW China, the Ro lower limits and essential features of the carbonization of organic matter in over-high maturity marine shale were examined using laser Raman, electrical and physical property characterization techniques. Three preliminary conclusions are drawn:(1) The lower limit of Ro for the carbonization of Type I-II1 organic matter in marine shale is 3.5%; when the Ro is less than 3.4%, carbonization of organic matter won't happen in general; when the Ro ranges from 3.4% to 3.5%, non-carbonization and weak carbonization of organic matter may coexist; when the Ro is higher than 3.5%, the carbonization of organic matter is highly likely to take place.(2) Organic-rich shale entering carbonization phase have three basic characteristics: log resistivity curve showing a general "slender neck" with low-ultralow resistance response, Raman spectra showing a higher graphite peak, and poor physical property(with matrix porosity of only less than 1/2 of the normal level).(3) The quality damage of shale reservoir caused by the carbonization of organic matter is almost fatal, which primarily manifests in depletion of hydrocarbon generation capacity, reduction or disappearance of organic pores and intercrystalline pores of clay minerals, and drop of adsorption capacity to natural gas. Therefore, the lower limit of Ro for the carbonization of Type I-II1 organic matter should be regarded as the theoretically impassable red line of shale gas exploration in the ancient marine shale formations. The organic-rich shale with low-ultralow resistance should be evaluated effectively in area selection to exclude the high risk areas caused by the carbonization of organic matter. The target organic-rich shale layers with low-ultralow resistance drilled during exploration and development should be evaluated on carbonization level of organic matter, and the deployment plan should be adjusted according to the evaluation results in time. 展开更多
关键词 Lower SILURIAN Longmaxi Formation MARINE SHALE thermal maturity organic matter CARBONIZatION resistivity LOGGING exploration risk
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VMAT技术下右侧乳腺癌改良根治术后增加内乳区照射对危及器官剂量学的影响 被引量:1
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作者 袁小龙 张洪波 +2 位作者 程菁菁 吴爱林 张朋 《中国医疗设备》 2023年第12期69-73,共5页
目的 探讨容积旋转调强放疗(Volumetric Modulated Arc Therapy,VMAT)技术下右侧乳腺癌改良根治术后增加内乳区照射对心肺等危及器官剂量的影响。方法 选取2019年7月至2022年7月82例接受改良根治术后辅助放疗的右侧乳腺癌患者,常规勾画... 目的 探讨容积旋转调强放疗(Volumetric Modulated Arc Therapy,VMAT)技术下右侧乳腺癌改良根治术后增加内乳区照射对心肺等危及器官剂量的影响。方法 选取2019年7月至2022年7月82例接受改良根治术后辅助放疗的右侧乳腺癌患者,常规勾画胸壁及锁骨上下淋巴引流区,每例患者均勾画2个放疗靶区,分别为包含内乳淋巴结引流区[PTV-IMN(+)]及不包含内乳区[PTV-IMN(-)]。分别为2个靶区设计放疗计划,比较两组患者在接受VMAT时心肺等危及器官的剂量学差异。通过剂量体积直方图计算靶区和危及器官剂量学参数。对符合正态分布的连续变量使用t检验。结果 对82例右侧乳腺癌包含或不包含内乳区的两种放疗计划对比发现,PTV-IMN(+)组在患侧肺的V_(5 Gy)、V_(10 Gy)、V_(30 Gy)、D_(mean)高于PTV-IMN(-)组(P<0.05);而两组V_(20 Gy)比较并无统计学差异(P>0.05)。PTV-IMN(+)组心脏的D_(mean)高于PTV-IMN(-)组[(3.75±0.41)Gy vs.(2.17±0.52)Gy](P<0.001),平均剂量增加约1.58 cGy;PTV-IMN(+)组心脏V_(5 Gy)、V10Gy、V20Gy以及RAD_(mean)的照射剂量亦比PTV-IMN(-)组有所增高(P<0.05);但并未发现两组计划在心脏V30 Gy、V40 Gy方面有统计学差异(P>0.05)。对比发现2021—2022年包含内乳区的计划在心脏的V30 Gy、D_(mean)、RAD_(mean)较2019—2020年有下降(P<0.05)。结论 对于右侧乳腺癌患者增加内乳区照射会一定程度增加患侧肺及心脏的照射剂量,但对于部分高危乳腺癌患者在接受辅助放疗时,在严格控制心肺剂量的前提下,仍可考虑将内乳区包括在内。 展开更多
关键词 乳腺癌 内乳区 容积调强放疗 危及器官 剂量学
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Organ at Risk Doses during High Dose Rate Intracavitary Brachytherapy for Cervical Cancer: A Dosimetric Study
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作者 N. V. Vinin Joneetha Jones +6 位作者 V. T. Ajas Geetha Muttath C. A. Suja E. K. Nabeel Yahiya P. N. Shoaib Nawaz Arun P. Narendran P. Shimjith 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第4期472-478,共7页
Background: Treatment of Cervical cancer includes a combination of external beam radiotherapy (EBRT) with intracavitary brachytherapy (ICBT). ICBT helps to boost radiation dose to primary disease. Organs like rectum, ... Background: Treatment of Cervical cancer includes a combination of external beam radiotherapy (EBRT) with intracavitary brachytherapy (ICBT). ICBT helps to boost radiation dose to primary disease. Organs like rectum, bladder, sigmoid and small bowel lie close to the cervix region and these organs receive dose from EBRT as well as ICBT and we want to know the dose to these organ at risk (OAR). Materials & Methods: Dosimetric details of 174 ICBT applications done in 58 patients were retrospectively analysed. All patients received EBRT dose of 50.4 Gy in 28 fractions. All patients had ICBT, three sessions with 7 Gy prescribed to point A. Dosimetric data including dose to right and left point A and dose to OARs were recorded from Oncentra Planning System. Results: Mean dose to point A on right side was 6.89 Gy and left side was 6.91 Gy. Mean D2cc dose to rectum, bladder, sigmoid and small bowel was 3.5 Gy, 5.25 Gy, 4.75 Gy and 4.2 Gy respectively. Mean EQD2 dose combining EBRT and ICBT in point A was 78.7 Gy on right side and 79 Gy on left side. Mean EQD2 doses to D2cc of rectum, bladder, sigmoid and small bowel was 62 Gy, 74.4 Gy, 70.5 Gy and 66.5 Gy respectively. Conclusion: From the results of this dosimetric study it is evident that OARs like rectum, sigmoid, bladder & bowel are receiving only acceptable doses of radiation using point A prescribed CT based ICBT planning. Hence with regards to OAR doses, CT based ICBT planning with dose prescribed to point A is a feasible option. 展开更多
关键词 Intracavitary BRACHYTHERAPY CARCINOMA CERVIX ORGAN at risk High DOSE Rate BRACHYTHERAPY
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Waterlogging risk assessment based on self-organizing map(SOM)artificial neural networks:a case study of an urban storm in Beijing 被引量:2
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作者 LAI Wen-li WANG Hong-rui +2 位作者 WANG Cheng ZHANG Jie ZHAO Yong 《Journal of Mountain Science》 SCIE CSCD 2017年第5期898-905,共8页
Due to rapid urbanization, waterlogging induced by torrential rainfall has become a global concern and a potential risk affecting urban habitant's safety. Widespread waterlogging disasters haveoccurred almost annu... Due to rapid urbanization, waterlogging induced by torrential rainfall has become a global concern and a potential risk affecting urban habitant's safety. Widespread waterlogging disasters haveoccurred almost annuallyinthe urban area of Beijing, the capital of China. Based on a selforganizing map(SOM) artificial neural network(ANN), a graded waterlogging risk assessment was conducted on 56 low-lying points in Beijing, China. Social risk factors, such as Gross domestic product(GDP), population density, and traffic congestion, were utilized as input datasets in this study. The results indicate that SOM-ANNis suitable for automatically and quantitatively assessing risks associated with waterlogging. The greatest advantage of SOM-ANN in the assessment of waterlogging risk is that a priori knowledge about classification categories and assessment indicator weights is not needed. As a result, SOM-ANN can effectively overcome interference from subjective factors,producing classification results that are more objective and accurate. In this paper, the risk level of waterlogging in Beijing was divided into five grades. The points that were assigned risk grades of IV or Vwere located mainly in the districts of Chaoyang, Haidian, Xicheng, and Dongcheng. 展开更多
关键词 Waterlogging risk assessment Self-organizing map(SOM) neural network Urban storm
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Risk of infectious diseases and cutaneous tumours in solid organ recipients: A meta-analysis of literature
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作者 Paola Savoia Giovanni Cavaliere Paolo Fava 《World Journal of Meta-Analysis》 2015年第1期11-19,共9页
AIM: To compare the risk of cutaneous infections and tumours in kidney transplant recipients with data recently published about this topic.METHODS: In the present work, we evaluated the incidence of bacterial, fungal ... AIM: To compare the risk of cutaneous infections and tumours in kidney transplant recipients with data recently published about this topic.METHODS: In the present work, we evaluated the incidence of bacterial, fungal and viral cutaneous infectious diseases and the development of skin cancers in a cohort of 436 patients who underwent a renal transplantation. The median age at transplantation of our patients was 50 years and the median duration of the immunosuppression was of 7.2 years. Data obtainedfrom our cohort were compared with those obtained by a systematic review of the literature of the last 20 years about the same topic.RESULTS: Infectious diseases were the most frequent dermatological disorders that were diagnosed after transplantation, affecting about the 16.5% of patients. Herpes virus reactivation occurs in about the 35% of patients and is more common within 6 mo from transplantation, whereas when the immunosuppression is reduced, skin infections are mainly represented by Human Papilloma Virus infections and localized mycosis, such as pityriasis versicolor and superficial candidiasis. Bacterial infections were relatively rare and occur mainly in the first months after transplantation. The cumulative risk to develop skin cancer enhance significantly over the time, as consequence of longterm immunosuppressive regiments. Endogenous and exogenous risk factors, as well as the schedule of immunosuppression can play a role and justify the different incidence of skin cancer in the various series. CONCLUSION: Skin infections and cancer, commonly diagnosed in transplanted patients, impact on survival and life-quality, justifying the realization of follow-up programs for the early diagnosis and treatment. 展开更多
关键词 Skin infectious disease Cutaneous tumours Transplantations risk Solid organ recipients
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Assessment of Public Health Risks Associated with Naphthalene Entering Residences and Commercial Space from Vapor Intrusion at MGP Sites
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作者 Robin DeHate Brian Skelly +2 位作者 Marie Bourgeois Giffe Johnson Raymond Harbison 《Journal of Environmental Protection》 2013年第12期11-17,共7页
Naphthalene, a constituent of coal tar, is a contaminant frequently found at former manufactured gas plants (MGP). Development at these sites has resulted in residential and commercial areas with potential exposures f... Naphthalene, a constituent of coal tar, is a contaminant frequently found at former manufactured gas plants (MGP). Development at these sites has resulted in residential and commercial areas with potential exposures from vapor intrusion adversely affecting indoor air of residences and buildings. Naphthalene is routinely analyzed in soil vapor intrusion assessments for properties overlying and surrounding former MGP sites. The United States Environmental Protection Agency (EPA) has a proposed unit risk factor and the State of California has promulgated a unit risk factor for naphthalene. Naphthalene exposure from vapor intrusion is potentially a public health risk. The purpose of this study was to evaluate three sites located in the northeast United States to determine the frequency of naphthalene detection in indoor air. A total of 79 properties were included in the study. A total of 546 indoor air samples were analyzed for naphthalene on 161 occasions. Naphthalene concentrations ranged from 0.26 to 51 μg/m3 of air. Only 3 of the 546 indoor air samples detected naphthalene above the ninety-fifth percentile background value of 12 μg/m3 of air. Risk analysis indicated naphthalene vapor intrusion was not a public health risk among the 79 properties built on or near the former MGP sites. 展开更多
关键词 Soil Vapor INTRUSION NAPHTHALENE VOLatILE Organic Compounds risk ASSESSMENT Manufactured Gas Plant
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An ecologically-based method for selecting ecological indicators for assessing risks to biological diversity from genetically-engineered plants 被引量:1
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作者 D.A.Andow Gabor L.Lvei +13 位作者 Salvatore Arpaia Lewis Wilson Eliana M.G.Fontes Angelika Hilbeck Andreas Lang Nguyên Vǎn Tu't C.S.S.Pires E.R.Sujii Claudia Zwahlen A.N.E.Birch Deise M.F.Capalbo Kristina Prescott Celso Omoto Adam R.Zeilinger 《生物安全学报》 2013年第3期141-156,共16页
The environmental risks associated with genetically-engineered( GE) organisms have been controversial,and so have the models for the assessment of these risks. We propose an ecologically-based environmental risk asses... The environmental risks associated with genetically-engineered( GE) organisms have been controversial,and so have the models for the assessment of these risks. We propose an ecologically-based environmental risk assessment( ERA) model that follows the 1998 USEPA guidelines,focusing on potential adverse effects to biological diversity. The approach starts by( 1) identifying the local environmental values so the ERA addresses specific concerns associated with local biological diversity. The model simplifies the indicator endpoint selection problem by( 2) classifying biological diversity into ecological functional groups and selecting those that deliver the identified environmental values.( 3) All of the species or ecosystem processes related to the selected functional groups are identified and( 4) multi-criteria decision analysis( MCDA) is used to rank the indicator endpoint entities,which may be species or ecological processes. MCDA focuses on those species and processes that are critical for the identified ecological functions and are likely to be highly exposed to the GE organism. The highest ranked indicator entities are selected for the next step.( 5) Relevant risk hypotheses are identified. Knowledge about the specific transgene and its possible environmental effects in other countries can be used to assist development of risk hypotheses.( 6) The risk hypotheses are ranked using MCDA with criteria related to the severity of the potential risk. The model emphasizes transparent,expert-driven,ecologically-based decision-making and provides formal methods for completing a screening level-ERA that can focus ERA on the most significant concerns. The process requires substantial human input but the human capital is available in most countries and regions of the world. 展开更多
关键词 生物多样性 基因工程植物 风险评估 生态指标 基础 环境风险评价 生态系统过程 环境价值
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Multi-Scale Network for Thoracic Organs Segmentation
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作者 Muhammad Ibrahim Khalil Samabia Tehsin +2 位作者 Mamoona Humayun N.Z Jhanjhi Mohammed A.AlZain 《Computers, Materials & Continua》 SCIE EI 2022年第2期3251-3265,共15页
Medical Imaging Segmentation is an essential technique for modern medical applications.It is the foundation of many aspects of clinical diagnosis,oncology,and computer-integrated surgical intervention.Although signifi... Medical Imaging Segmentation is an essential technique for modern medical applications.It is the foundation of many aspects of clinical diagnosis,oncology,and computer-integrated surgical intervention.Although significant successes have been achieved in the segmentation of medical images,DL(deep learning)approaches.Manual delineation of OARs(organs at risk)is vastly dominant but it is prone to errors given the complex irregularities in shape,low texture diversity between tissues and adjacent blood area,patientwide location of organisms,and weak soft tissue contrast across adjacent organs in CT images.Till now several models have been implemented onmulti organs segmentation but not caters to the problemof imbalanced classes some organs have relatively small pixels as compared to others.To segment OARs in thoracic CT images,we proposed the model based on the encoder-decoder approach using transfer learning with the efficientnetB7 DL model.We have built a fully connected CNN(Convolutional Neural network)having 5 layers of encoding and 5 layers of decoding with efficientnetB7 specifically to tackle imbalance class pixels in an accurate way for the segmentation of OARs.Proposed methodology achieves 0.93405 IOU score,0.95138 F1 score and class-wise dice score for esophagus 0.92466,trachea 0.94257,heart 0.95038,aorta 0.9351 and background 0.99891.The results showed that our proposed framework can be segmented organs accurately. 展开更多
关键词 Deep learning convolutional neural network computed tomography organs at risk computer-aided diagnostic
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