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Antibiotic sensitivity pattern of bacterial pathogens in the intensive care unit of Fatmawati Hospital,Indonesia 被引量:7
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作者 Maksum Radji Siti Fauziah Nurgani Aribinuko 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2011年第1期39-42,共4页
Objective:To evaluate the sensitivity pattern of bacterial pathogens in the intensive care unit(ICU) of a tertiary care of Falmawati Hospital Jakarta Indonesia.Methods:A cross sectional retrospective study of bacteria... Objective:To evaluate the sensitivity pattern of bacterial pathogens in the intensive care unit(ICU) of a tertiary care of Falmawati Hospital Jakarta Indonesia.Methods:A cross sectional retrospective study of bacterial pathogen was carried out on a total of 722 patients that were admitted to the ICU of Fatmawati Hospital Jakarta Indonesia during January 2009 to March 2010. All bacteria were identified by standard microbiologic methods,and(heir antibiotic susceptibility testing was performed using disk diffusion method.Results:Specimens were collected from 385 patients who were given antimicrobial treatment,of which 249(64.68%) were cultured positive and 136(35.32%) were negative.The most predominant isolate was Pseudomonas aeruginosa(P.aeruginosa)(26.5%) followed by Klebsiella pneumoniae(K.pneumoniae)(15.3%) and Staphylococcus epidermidis(14.9%).P.aeruginosa isolates showed high rate of resistance to cephalexin(95.3%),cefotaxime(64.1%),and ceftriaxone(60.9%).Amikacin was the most effective(84.4%) antibiotic against P.aeruginosa followed by imipenem(81.2%),and meropenem(75.0%).K.pneumoniae showed resistance to cephalexin(86.5%),ceftriaxone(75.7%),ceftazidime(73.0%),cefpirome(73.0%) and cefotaxime(67.9%),respectively.Conclusions:Most bacteria isolated from ICU of Fatmawati Hospital Jakarta Indonesia were resistant to the third generation of cephalosporins,and quinolone antibiotics.Regular surveillance of antibiotic susceptibility pallerns is very important for setting orders to guide the clinician in choosing empirical or directed therapy of infected patients. 展开更多
关键词 Antibiotic susceptibility intensive care unit BACTERIAL RESISTANCE BACTERIAL pathogen Sensitivity pattern Antimicrobial RESISTANCE Pseudomonas AERUGINOSA KLEBSIELLA PNEUMONIAE Isolate Specimen
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Prognostic factors and failure patterns in non-metastatic nasopharyngeal carcinoma after intensity-modulated radiotherapy 被引量:47
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作者 Yan-Ping Mao Ling-Long Tang +7 位作者 Lei Chen Ying Sun Zhen-Yu Qi Guan-Qun Zhou Li-Zhi Liu Li Li Ai-Hua Lin Jun Ma 《Chinese Journal of Cancer》 SCIE CAS CSCD 2016年第12期673-682,共10页
Background: The prognostic values of staging parameters require continual re?assessment amid changes in diag?nostic and therapeutic methods. This study aimed to identify the prognostic factors and failure patterns of ... Background: The prognostic values of staging parameters require continual re?assessment amid changes in diag?nostic and therapeutic methods. This study aimed to identify the prognostic factors and failure patterns of non?meta?static nasopharyngeal carcinoma(NPC) in the intensity?modulated radiotherapy(IMRT) era.Methods: We reviewed the data from 749 patients with newly diagnosed, biopsy?proven, non?metastatic NPC in our cancer center(South China, an NPC endemic area) between January 2003 and December 2007. All patients under?went magnetic resonance imaging(MRI) before receiving IMRT. The actuarial survival rates were estimated using the Kaplan–Meier method, and survival curves were compared using the log?rank test. Multivariate analyses with the Cox proportional hazards model were used to test for the independent prognostic factors by backward eliminating insigniicant explanatory variables.Results: The 5?year occurrence rates of local failure, regional failure, locoregional failure, and distant failure were 5.4, 3.0, 7.4, and 17.4%, respectively. The 5?year survival rates were as follows: local relapse?free survival, 94.6%; nodal relapse?free survival, 97.0%; distant metastasis?free survival, 82.6%; disease?free survival, 75.1%; and overall survival, 82.0%. Multivariate Cox regression analysis revealed that orbit involvement was the only signiicant prognostic fac?tor for local failure(P = 0.011). Parapharyngeal tumor extension, retropharyngeal lymph node involvement, and the laterality, longest diameter, and Ho's location of the cervical lymph nodes were signiicant prognostic factors for both distant failure and disease failure(all P < 0.05). Intracranial extension had signiicant prognostic value for distant failure(P = 0.040).Conclusions: The key failure pattern for NPC was distant metastasis in the IMRT era. With changes in diagnostic and therapeutic technologies as well as treatment modalities, the signiicant prognostic parameters for local control have also been altered substantially. 展开更多
关键词 Nasopharyngeal carcinoma intensity-modulated radiotherapy PROGNOSIS Failure pattern Tumor staging
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Causative bacteria of ventilator-associated pneumonia in intensive care unit in Bahrain:Prevalence and antibiotics susceptibility pattern 被引量:2
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作者 Mohamed Eliwa Hassan Safaa Abdulaziz Al-Khawaja +5 位作者 Nermin Kamal Saeed Sana Abdulaziz Al-Khawaja Mahmood Al-Awainati Sara Salah Yusuf Radhi Mohamed Hameed Alsaffar Mohammed Al-Beltagi 《World Journal of Critical Care Medicine》 2023年第3期165-175,共11页
BACKGROUND Ventilator-associated pneumonia(VAP)is defined as pneumonia that occurs two calendar days following endotracheal intubation or after that.It is the most common infection encountered among intubated patients... BACKGROUND Ventilator-associated pneumonia(VAP)is defined as pneumonia that occurs two calendar days following endotracheal intubation or after that.It is the most common infection encountered among intubated patients.VAP incidence showed wide variability between countries.AIM To define the VAP incidence in the intensive care unit(ICU)in the central gove-rnment hospital in Bahrain and review the risk factors and the predominant bacterial pathogens with their antimicrobial susceptibility pattern.METHODS The research was a prospective cross-sectional observational study over six months from November 2019 to June 2020.It included adult and adolescent patients(>14 years old)admitted to the ICU and required intubation and mechanical ventilation.VAP was diagnosed when it occurred after 48 h after endotracheal intubation using the clinical pulmonary infection score,which considers the clinical,laboratory,microbiological,and radiographic evidence.RESULTS The total number of adult patients admitted to the ICU who required intubation and mechanical ventilation during the study period was 155.Forty-six patients developed VAP during their ICU stay(29.7%).The calculated VAP rate was 22.14 events per 1000 ventilator days during the study period,with a mean age of 52 years±20.Most VAP cases had late-onset VAP with a mean number of ICU days before the development of VAP of 9.96±6.55.Gram-negative contributed to most VAP cases in our unit,with multidrug-resistant Acinetobacter being the most identified pathogen.CONCLUSION The reported VAP rate in our ICU was relatively high compared to the international benchmark,which should trigger a vital action plan for reinforcing the implementation of the VAP prevention bundle. 展开更多
关键词 Ventilator-associated pneumonia intensive care unit Antibiotics susceptibility pattern Kingdom of Bahrain Adults Bacterial resistance ACINETOBACTER
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Tuning the intensity statistics of random speckle patterns
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作者 Fan Meng Yue Zhao +1 位作者 Yun-Zuo Zhang Lei Huo 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第5期327-331,共5页
Speckle patterns are a fundamental tool in a variety of physical and optical applications. Here, we investigate a method of precisely tuning the intensity statistics of random speckle patterns into a desirable pattern... Speckle patterns are a fundamental tool in a variety of physical and optical applications. Here, we investigate a method of precisely tuning the intensity statistics of random speckle patterns into a desirable pattern that possesses the same spatial correlation length and similar statistics distribution. This tuning mechanism relies on the derivation of the transform function and transmission matrix, which achieves different contrasts while maintaining the same average value or energy level. The statistics properties of the generated speckle patterns are further investigated by analyzing the standard deviation under different fitting parameters. Precisely tuning the intensity statistics of random speckle patterns could be useful for both fundamental research and practical applications, such as microscopy, imaging, and optical manipulation. 展开更多
关键词 RANDOM SPECKLE pattern intensITY STATISTICS local intensITY TRANSFORMATION optical MANIPULATION
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Mortality Pattern in Intensive Care Unit: Experience at Abakaliki Southeastern Nigeria
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作者 Chukwuemeka O. Eze Francis C. Okoro +3 位作者 Thomas Nnaji Monday Nwobodo Uma Kalu Richard Ewah 《World Journal of Cardiovascular Diseases》 2020年第7期473-482,共10页
<strong>Background: </strong><span style="font-family:;" "=""><span style="font-family:Verdana;">An intensive care unit (ICU) is a special unit of a hospital ... <strong>Background: </strong><span style="font-family:;" "=""><span style="font-family:Verdana;">An intensive care unit (ICU) is a special unit of a hospital that provides intensive treatment for patients with severe or life-threatening illnesses and injuries, which require constant care and close monitoring with life support equipment. The mortality rate is still very high in most ICUs especially in the developing countries due to late presentation of patients, unavailability of well trained staff and lack of life support equipment. There has not been any previous study on the mortality pattern in ICU of Alex Ekwueme Federal University Teaching Hospital Abakaliki (AEFUTHA). It is against this background that we embarked on this retrospective descriptive hospital based study of the mortality pattern in ICU of a Tertiary Hospital in Abakaliki, South-eastern Nigeria. </span><b><span style="font-family:Verdana;">Method: </span></b><span style="font-family:Verdana;">This is a retrospective descriptive hospital based study. The admission and discharge registers of the ICU ward were used to extract information on biodata, diagnosis, duration and outcome of all admissions from January to December 2019 (12</span></span><span style="font-family:Verdana;"> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">months). </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">A total of 174 (male 113, female 71) patients were admitted over the 12</span></span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">months period with mean age of 46.31</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">±</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">12.28</span><span style="font-family:Verdana;"> </span><span style="font-family:Verdana;">years. Seventy</span><span style="font-family:Verdana;">-</span><span style="font-family:;" "=""><span style="font-family:Verdana;">one (40.8%) of the patients died from predominantly stroke, acute abdomen, trauma, sepsis, renal failure, acute diabetic complications and cancer in descending order. Acute diabetic complications had 100% case fatality rate, followed by stroke (71%), renal failure (62.5%), cancer (60%), sepsis (55.5%), acute abdomen (34%) and trauma (23%). The mean duration of ICU admission was 4.2 days for the non-survivors and 6.3 days for survivors. </span><b><span style="font-family:Verdana;">Conclusion: </span></b><span style="font-family:Verdana;">The ICU mortality rate was high and constituted of mainly stroke, acute abdomen and trauma which are essentially preventable. Female sex, medical diagnosis and ICU admission duration of less than 6 days were associated with higher ICU mortality.</span></span> 展开更多
关键词 pattern MORTALITY intensive Care Unit Abakaliki South-Eastern Nigeria
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Seasonal Suspended Particles Distribution Patterns in Western South Yellow Sea Based on Acoustic Doppler Current Profiler Observation 被引量:1
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作者 LI Jianchao LI Guangxue +5 位作者 XU Jishang QIAO Lulu DONG Ping DING Dong LIU Shidong SUN Pingkuo 《Journal of Ocean University of China》 SCIE CAS 2015年第3期385-398,共14页
An Acoustic Doppler Current Profiler (ADCP) observation site was set up in the Western South Yellow Sea from 2012 to 2013 to study the local suspended particle matters (SPM) distribution pattern. The SPM concentra... An Acoustic Doppler Current Profiler (ADCP) observation site was set up in the Western South Yellow Sea from 2012 to 2013 to study the local suspended particle matters (SPM) distribution pattern. The SPM concentration could be semi-quantitatively represented by backscatter intensity (Sv), converted by the echo intensity (E/) of ADCP. Results show two types of SPM in the water column: the quasi-biological SPM and quasi-mineral SPM. The quasi-biological SPM mainly exists in summer half year and is con- centrated above the thermocline. It has periodically diurnal variations with high concentration at night and low concentration in the daytime. The quasi-mineral SPM is located in lower part of the water column, with similar relation to monthly tidal current variation all year round. However, the daily quasi-mineral SPM distribution patterns vary between summer and winter half year. The sunlight is thought to be the origin factor leading to the diurnally vertical motion of the biological features, which might cause the diurnal Sv variation. Unlike in winter half year when tidal current is relatively single driving force of the monthly SPM pattern, the high speed current near the thermocline is also responsible for the concentration of quasi-mineral SPM in summer half year. The sediment input difference between summer and winter half year contribute to the varied daily variation of quasi-mineral SPM with re-suspended SPM ir~ winter and sediments from Yellow Sea Mud Area (YSMA) in summer. The seasonal variations in hydrodynamics, water structure and heavy-wind incidents are the primary factors influencing the differential seasonal SPM distribution patterns. 展开更多
关键词 the South Yellow Sea backscatter intensity suspended particle matters seasonal distribution patterns diurnal periodicvariation
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Numerical Simulation of a Courtyard under Different Ground Thermal Conditions and Flow Patterns
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作者 何龙靓 钟珂 +2 位作者 何燕娜 亢燕铭 杨方 《Journal of Donghua University(English Edition)》 EI CAS 2016年第1期121-126,共6页
The impact of thermal conditions of the ground on ventilation in the interior courtyard and rooms of enclosed building is very important to improve the air quality in courtyard. The computational fluid dynamics( CFD) ... The impact of thermal conditions of the ground on ventilation in the interior courtyard and rooms of enclosed building is very important to improve the air quality in courtyard. The computational fluid dynamics( CFD) model was used to investigate the flow field of a certain courtyard and analyze the static differential pressure between the two sides of the vent and ventilation conditions of the courtyard. The results indicate that thermal effects not only changed the air flow pattern of the interior courtyard but also obviously increased the flow velocity of the upper space of the courtyard. For the most of courtyard rooms,the absolute value of static differential pressure increases as the thermal intensity of the ground increases. In all wind directions,the air exchange rate of the courtyard increases with the higher thermal intensity of the ground which makes a greater influence on the increasing of the ventilation rate of the roof opening than that on the gate opening. 展开更多
关键词 thermal intensity natural ventilation flow patterns numerical simulation
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Evaluation of Intensive Land Utilization based on Anti-planning Concept
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作者 WENG Dalai 《Journal of Landscape Research》 2012年第11期23-26,28,共5页
Based on the gist of anti-planning,evaluation standards and methods of intensive land utilization were re-examined according to the inverse planning procedures.Significant role of compulsory non-development zone(simil... Based on the gist of anti-planning,evaluation standards and methods of intensive land utilization were re-examined according to the inverse planning procedures.Significant role of compulsory non-development zone(similar to the traditional"non-construction land")among the planning fruits in the intensive utilization of urban land resources and relevant index weights in the evaluation system were re-weighed.In land evaluation,relevant control indexes of compulsory non-development zone were first calculated and evaluated,healthy and sustainable development coefficients of land were obtained and regarded as the core content of the whole evaluation system. 展开更多
关键词 EVALUATION of intensive LAND UTILIZATION Anti-planning LANDSCAPE safety pattern HEALTHY and sustainable development
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Pain Management and Factors Associated with Its Severity among Post Surgical Patients Admitted in the Intensive Care Unit at Muhimbili National Hospital, Tanzania
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作者 Rebecca Samwel Respicious Boniface 《Open Journal of Anesthesiology》 2019年第2期23-33,共11页
Background: Pain is the common experience among post operative patients admitted to the intensive care unit. Inadequate management can lead to undesired complications which can increase risk for morbidity and mortalit... Background: Pain is the common experience among post operative patients admitted to the intensive care unit. Inadequate management can lead to undesired complications which can increase risk for morbidity and mortality. Objective: The aim of this study was to assess pain management and factors associated with its severity among post surgical patients admitted in intensive care unit at MNH. Method: A prospective study was conducted from October 2017 to February 2018 involving a total of 123 post operative patients aged 18 years and above admitted to the surgical and obstetric intensive care units. Structured questionnaires were used to obtain the required perioperative information. Severity of pain was assessed by using the Numerical Rating Scale (NRS). Data was analyzed using SPSS version 23.0. Frequency, percentages, tables and charts were used to summarize the study findings. Bivariate analysis and multivariate logistic regression were done. P-value of Results: The prevalence of severe post operative pain within 24 and 72 hours was 32.1% and 41.5% respectively. Pre operative use of analgesia (OR: 2.66, CI: 1.15 - 6.12, P value = 0.02), abdominal surgery (OR: 4.12 CI: 1.12 - 15.88, P value = 0.03) and thoracic surgeries (OR;7.42, CI: 1.54 - 35.88, P value = 0.01) was significantly associated with severe pain. Age, sex, ASA class, duration of surgery, and level of education did not show significant association with pain severity. Opioids prescribed postoperatively were pethidine (70.7%), morphine (11.4%) and fentanyl (11.4%). Other analgesics used were paracetamol (60.2%) and diclofenac (22%). Conclusion: The magnitude of post operative pain was high. Pre operative uses of analgesia, abdominal and thoracic surgery were the factors associated with severe pain. Pethidine and paracetamol were the most prescribed drugs, however the prescription pattern used was inadequate to control pain. 展开更多
关键词 POST OPERATIVE PAIN intensive Care Unit (ICU) PAIN SEVERITY Prescription pattern ANALGESIA
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New avenues for reducing intensive care needs in patients with chronic spinal cord injury
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作者 Pierre A Guertin 《World Journal of Critical Care Medicine》 2016年第4期201-203,共3页
Relatively soon after their accident, patients suffering a spinal cord injury(SCI) begin generally experiencing the development of significant, often life-threatening secondary complications. Many of which are associa... Relatively soon after their accident, patients suffering a spinal cord injury(SCI) begin generally experiencing the development of significant, often life-threatening secondary complications. Many of which are associated with chronic physical inactivity-related immune function problems and increasing susceptibility to infection that repeatedly requires intensive care treatment. Therapies capable of repairing the spinal cord or restoring ambulation would normally prevent many of these problems but, as of now, there is no cure for SCI. Thus, management strategies and antibiotics remain the standard of care although antimicrobial resistance constitutes a significant challenge for patients with chronic SCI facing recurrent infections of the urinary tract and respiratory systems. Identifying alternative therapies capable of safe and potent actions upon these serious health concerns should therefore be considered a priority. This editorial presents some of the novel approaches currently in development for the prevention of specific infections after SCI. Among them, brain-permeable small molecule therapeutics acting centrally on spinal cord circuits that can augment respiratory capabilities or bladder functions. If eventually approved by regulatory authorities, some of these new avenues may potentially become clinically-relevant therapies capable of indirectly preventing the occurrence and/or severity of these lifethreatening complications in people with paraplegic or tetraplegic injuries. 展开更多
关键词 Prevention of intensive CARE problems Quality of CARE TEMPORARY recovery of VITAL functions MICTURITION SPINAL networks Central pattern generators
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Crack patterns corresponding to the residual strength plateau of ceramics subjected to thermal shock
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作者 H.-L.Hou X.-E Wu +3 位作者 P.Yan F.Song J.Li C.-P.Jiang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第3期670-674,共5页
The formation strength plateau of ceramics is addressed. A set of of 99A1203 are conducted, mechanism of the residual subjected to thermal shock thermal shock experiments where the thin specimens of 1 mm× 10 mm&... The formation strength plateau of ceramics is addressed. A set of of 99A1203 are conducted, mechanism of the residual subjected to thermal shock thermal shock experiments where the thin specimens of 1 mm× 10 mm×50 mm exhibit parallel through edge cracks, and thus permit quantitative measurements of the crack patterns. The cracks evolve with the severity of ther- mal shock. It is found that there is a correlation between the length and density of the thermal shock cracks. The increase of crack length weakens the residual strength, whereas the increase of crack density improves it. In a considerably wide temperature range, the two contrary effects just counteract each other; consequently a plateau appears in the variation curve of the residual strength. A comparison between the numerical and experimental results of the residual strength is made, and they are found in good agreement. This work is helpful to a deep understanding of the thermal shock failure of ceramics. 展开更多
关键词 Ceramics Thermal shock Crack patterns Residual strength - Stress intensity factor
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Diagnosis of focal spots at relativistic intensity utilizing coherent radiation from laser-driven flying electron sheets
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作者 Shirui Xu Zhuo Pan +22 位作者 Ying Gao Jiarui Zhao Shiyou Chen Zhusong Mei Xun Chen Ziyang Peng Xuan Liu Yulan Liang Tianqi Xu Tan Song Qingfan Wu Yujia Zhang Zhipeng Liu Zihao Zhang Haoran Chen Qihang Han Jundong Shen Chenghao Hua Kun Zhu Yanying Zhao Chen Lin Xueqing Yan Wenjun Ma 《Matter and Radiation at Extremes》 2025年第2期16-23,共8页
Experimental validation of laser intensity is particularly important for the study of fundamental physics at extremely high intensities.However,reliable diagnosis of the focal spot and peak intensity faces huge challe... Experimental validation of laser intensity is particularly important for the study of fundamental physics at extremely high intensities.However,reliable diagnosis of the focal spot and peak intensity faces huge challenges.In this work,we demonstrate for the firs time that the coherent radiation farfiel patterns from laser–foil interactions can serve as an in situ,real-time,and easy-to-implement diagnostic for an ultraintense laser focus.The laser-driven electron sheets,curved by the spatially varying laser fiel and leaving the targets at nearly the speed of light,produce doughnut-shaped patterns depending on the shapes of the focal spot and the absolute laser intensities.Assisted by particle-in-cell simulations,we can achieve measurements of the intensity and the focal spot,and provide immediate feedback to optimize the focal spots for extremely high intensity. 展开更多
关键词 diagnosis focal spot peak intensity laser foil interactions laser fi coherent radiation farfiel patterns laser driven electron sheets experimental validation laser intensity focal spot coherent radiation
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基于事件过程的珠江流域极端小时降水变化特征
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作者 宋晓猛 韦金江 张建云 《水科学进展》 北大核心 2026年第2期220-234,共15页
全球变暖背景下极端降水事件频发,对生态环境和人类社会构成严峻挑战,深入理解其变化特征对防洪减灾具有重要意义。本文利用多源数据融合的逐小时降水数据集,基于事件过程的极端小时降水(Event-based Extreme Hourly Precipitation,EEHP... 全球变暖背景下极端降水事件频发,对生态环境和人类社会构成严峻挑战,深入理解其变化特征对防洪减灾具有重要意义。本文利用多源数据融合的逐小时降水数据集,基于事件过程的极端小时降水(Event-based Extreme Hourly Precipitation,EEHP)分析框架,探讨珠江流域2000—2023年EEHP的时空变化特征,重点分析主导时间分布模式、历时-强度组合模式及其空间分布格局。结果表明:①EEHP总频次呈上升趋势,然而平均降水量和持续时间普遍呈下降趋势,年内高发期集中于5—6月,且日内降水主峰值多发于上午07:00—08:00和下午16:002个时段。②EEHP的各项指标具有相似的空间分布格局,总体为“西低东高”的分布特征。③前峰型时间分布模式为珠江流域EEHP的主导类型(占比87.4%),主要分布于流域西部的云贵-广西、东部的广东-福建及两广沿海地区,在春夏季最为活跃。④长历时-低强度EEHP是珠江流域事件占比最高的类型,低强度事件的空间分布呈“西北低、东南高”的格局,高强度事件的空间分布则相对均匀;不同组合类型的EEHP事件平均强度与平均历时呈现明显的逆向关系,平均历时随着平均强度增加而显著减小。 展开更多
关键词 极端小时降水 时间分布模式 季节性主导 历时-强度类型
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基于Wave Intensity技术的高血压患者动脉弹性参数与血瘀证积分的相关性分析 被引量:8
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作者 魏世超 骆杰伟 +7 位作者 陈玮吉 林宁 郑星宇 李建卫 任林 孟晓嵘 张莹莹 黄昉萌 《世界中西医结合杂志》 2012年第5期407-409,共3页
目的探讨应用Wave Intensity(WI)技术检测高血压患者动脉弹性参数与血瘀证积分的相关性。方法用ALOKA Prosoundα10彩色多普勒超声仪检测119例高血压基础病患者,及62例健康对照者,获取颈总动脉β(僵硬度)、Ep(弹性模量)、AC(顺应性)、AI... 目的探讨应用Wave Intensity(WI)技术检测高血压患者动脉弹性参数与血瘀证积分的相关性。方法用ALOKA Prosoundα10彩色多普勒超声仪检测119例高血压基础病患者,及62例健康对照者,获取颈总动脉β(僵硬度)、Ep(弹性模量)、AC(顺应性)、AI(增大指数)、PWVβ(β值推导的脉搏波传导速度)、PWV-WI(WI值推导的脉搏波传导速度)等数据,并评估血瘀证积分。结果高血压组β、Ep、AI、PWVβ、PWV-WI均值均高于对照组均值,而AC均值低于对照组均值,两组比较差异有统计学意义(P<0.05),而高血压血瘀证积分与β、Ep、PWVβ、PWV-WI值与呈正相关(分别为r=0.750,P<0.001;r=0.776,P<0.001;r=0.870,P<0.001;r=0.418,P<0.001),与AC呈负相关(r=-0.769,P<0.001),差异有统计学意义,血瘀证积分与AI无明显相关(r=0.023,P=0.800)。结论基于Wave Intensity技术检测的动脉弹性参数能较准确反映血瘀证程度,具有临床应用价值。 展开更多
关键词 WAVE intensITY 超声检查 高血压 血瘀证 动脉弹性参数
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土地利用类型、强度和景观格局对河流水质的多尺度影响
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作者 朱加应 彭双云 +3 位作者 林之强 杨玉钱 张瑞 黄帮梅 《湖泊科学》 北大核心 2026年第1期154-169,I0017,共17页
水质安全是保障生态系统功能、维护人类健康及实现可持续发展的关键要素。土地利用的类型、强度和景观格局作为人类活动的重要表征,对河流水质变化具有显著影响,且这种影响在不同时空尺度下存在差异。本研究以赤水河源区为研究对象,结... 水质安全是保障生态系统功能、维护人类健康及实现可持续发展的关键要素。土地利用的类型、强度和景观格局作为人类活动的重要表征,对河流水质变化具有显著影响,且这种影响在不同时空尺度下存在差异。本研究以赤水河源区为研究对象,结合河岸带和子流域两个尺度,采用方差分解和随机森林模型,量化土地利用类型、强度及景观格局3个维度对水质的独立贡献和综合影响,并识别了关键影响因子及其空间尺度。结果表明:①景观格局是影响水质变化的主要维度(33%~58%),其次为土地利用类型(11%~22%)和土地利用强度(4%~16%);②河岸带景观格局对水质的影响更显著,而子流域土地利用强度的解释力更大;③建设用地占比、建设用地强度和农田强度是关键的水质预测因子,森林占比和景观格局在减少总氮、化学需氧量方面发挥重要作用。研究显示,流域水质管理应根据不同土地利用特征,寻找河岸带与子流域尺度的最佳组合来制定管理措施。建议在河岸带尺度优先控制工业与生活污水点源,在子流域尺度强化农业面源治理,形成“点面结合”的管控体系。本研究为理解土地利用水质关系的多维度特征和尺度效应提供了新的实证,对于制定流域水土资源保护和空间优化策略具有重要的理论和实践意义。 展开更多
关键词 土地利用 水质 景观格局 土地利用强度 尺度效应 赤水河
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抚育采伐对次生杨桦林空间结构的短期影响
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作者 陈泽群 张忠辉 +5 位作者 刘玉伟 程福山 罗也 黄少旭 侯强 何怀江 《吉林农业大学学报》 北大核心 2026年第1期70-80,共11页
为探究不同采伐强度对次生杨桦林林分空间结构的影响,以张广才岭地区次生杨桦林为研究对象,选取具有代表性且林分情况相对一致的4块1 hm2(100 m×100 m)样地,按照样地胸高断面积设置采伐强度梯度:0(对照,ck)、20%(轻度采伐,LT)、30%... 为探究不同采伐强度对次生杨桦林林分空间结构的影响,以张广才岭地区次生杨桦林为研究对象,选取具有代表性且林分情况相对一致的4块1 hm2(100 m×100 m)样地,按照样地胸高断面积设置采伐强度梯度:0(对照,ck)、20%(轻度采伐,LT)、30%(中度采伐,MT)、40%(重度采伐,HT),计算不同采伐强度样地伐前及伐后角尺度、大小比数、混交度、密集度4个林分空间结构参数,为次生林空间结构优化提供科学依据。结果表明:不同采伐强度对伐前及伐后角尺度、大小比数、混交度、密集度影响不同,角尺度量化结果表明,经LT、MT处理后林分水平格局分布从聚集分布(0.534,0.521)调整为随机分布(0.494,0.480),HT处理由0.540调整为0.521,林分水平格局状况无变化;大小比数无明显变化(伐前:0.488,0.492,0.509;伐后:0.486,0.495,0.502);林分混交度经采伐后有不同程度提升(伐前:0.681,0.774,0.657;伐后:0.790,0.786,0.799);林分密集度经采伐后呈降低趋势(伐前:0.357,0.351,0.437;伐后:0.338,0.294,0.316)。不同采伐强度对9种主要树种的影响也存在差异,不同采伐强度间各树种角尺度变化无明显规律;采伐降低了山杨、白桦的大小分化程度,其他树种在各采伐强度下,除MT时春榆、水曲柳、色木槭降低外,均有不同程度的增加;采伐能够提高各树种混交状态,但LT、HT时紫椴、山槐在林分中的混交程度降低;伐后各树种密集度均有不同程度降低。综上,采伐短期内有利于改善林分空间结构和树种组成,其中30%采伐强度能优化林木水平分布格局、提高林木混合程度且对改善林分平均密集度效果最好。 展开更多
关键词 次生杨桦林 采伐强度 角尺度 大小比数 混交度 密集度
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不同降雨条件下尾矿库漫顶溃坝模型试验
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作者 罗朋志 王光进 +7 位作者 赵冰 李树建 王孟来 犹俊 李松林 朱源婷 林水泉 张飞 《黄金》 2026年第1期66-75,共10页
为探究强降雨条件下尾矿库浸润线的变化规律及溃坝后尾砂流的动态演进过程,以四川某尾矿库为工程案例,选取其原型范围内的关键区域,遵循相似理论建立尾矿库堆体溃坝模拟,采用相似模型,模型的几何参数设定为3 m×1 m×1 m。研究... 为探究强降雨条件下尾矿库浸润线的变化规律及溃坝后尾砂流的动态演进过程,以四川某尾矿库为工程案例,选取其原型范围内的关键区域,遵循相似理论建立尾矿库堆体溃坝模拟,采用相似模型,模型的几何参数设定为3 m×1 m×1 m。研究了强降雨条件下浸润线变化规律及漫顶溃坝后下泄尾砂流的演进规律。结果表明:尾矿库漫顶破坏的演化过程可细分为4个阶段,即漫顶启溃、纵向切深、横向扩宽、冲淤平衡。在漫顶溃坝的起始环节,多初始溃口并存的现象具有一定发生概率。其主溃口的形成与侵蚀程度和水流大小密切相关;初始溃口出现的时间会随着降雨强度的增大而提前,但在溃口形成时,浸润线测管水位高度在不同降雨条件下呈现相反趋势,即80 mm/h>100 mm/h>120 mm/h。降雨初期,降雨强度对浸润线的影响存在空间差异性,干滩面远端与中部的浸润线受其影响较为突出,而坝体中部和前端的浸润线则基本不受降雨强度变化的明显干扰,即越靠近库尾,水分入渗量越大,致使该区域浸润线抬升速率明显高于坝体附近。 展开更多
关键词 尾矿库 漫顶溃坝 演进规律 模型试验 浸润线 降雨强度
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西宁南北山针阔混交林乔木层树种空间分布格局与种间关联性研究
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作者 刘瑶 王彬 +3 位作者 郑贞贞 赵文锋 温海艳 季海明 《青海农林科技》 2026年第1期29-35,共7页
以西宁市南北山针阔混交林为研究对象,基于野外调查数据,采用聚集强度指数、x^(2)值和关联度指数对乔木层树种的空间格局进行分析;基于2×2联列表的联结系数AC,Jaccard相似系数(PC)研究乔木层树种的种间关联性。结果显示:所研究的1... 以西宁市南北山针阔混交林为研究对象,基于野外调查数据,采用聚集强度指数、x^(2)值和关联度指数对乔木层树种的空间格局进行分析;基于2×2联列表的联结系数AC,Jaccard相似系数(PC)研究乔木层树种的种间关联性。结果显示:所研究的14个树种中杜梨、旱柳、落叶松、沙棘、沙枣、小叶杨的K值和C_(A)值均小于0,其余种群皆表现为C>1,K>0,C_(A)>0,I>0,PAI>1,大多数种群空间上均呈现强聚集分布状态,其中新疆杨的PAI值接近1,其分布格局处于由低强度聚集向随机分布的过渡阶段,沙棘则表现出由弱均匀分布向随机分布过渡的特征;x^(2)值检验显示,多数树种种间关联性不显著;基于AC和PC值的分析表明,75%以上的种对AC和PC值均低于0.2,表明种间联结程度普遍较弱。结果表明,西宁南北山针阔混交林乔木层树种的空间分布以聚集分布格局为主,仅少数树种呈现向随机分布过渡的趋势;种间关联性整体较弱,群落结构尚不稳定,表明该森林群落处于演替的初级阶段。研究结果为该地区林业生态建设与保护恢复提供科学依据。 展开更多
关键词 针阔混交林 空间分布格局 聚集强度指数 种间关联性
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现代牛郎织女的生育效应——基于通勤婚姻对生育意愿的影响及机制研究
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作者 肖涵 黎晓锋 《山西财经大学学报》 北大核心 2026年第1期40-51,共12页
探究通勤婚姻模式对居民生育意愿的影响,对于理解当代家庭在经济发展与个体需求平衡下的决策机制具有重要的现实意义。利用中国综合社会调查数据,实证分析通勤婚姻对居民生育意愿的影响及其作用机制。研究发现,通勤婚姻显著降低居民生... 探究通勤婚姻模式对居民生育意愿的影响,对于理解当代家庭在经济发展与个体需求平衡下的决策机制具有重要的现实意义。利用中国综合社会调查数据,实证分析通勤婚姻对居民生育意愿的影响及其作用机制。研究发现,通勤婚姻显著降低居民生育意愿,且对多孩生育意愿抑制作用最大。机制检验表明,通勤婚姻主要通过弱化传统角色认知、减少社会信任、增强认同偏移来降低居民生育意愿。异质性分析显示,该影响存在劳动强度、就业模式和年龄异质性,对超时劳动、正式就业、青年阶段居民的生育意愿影响更大。 展开更多
关键词 通勤婚姻 生育意愿 角色认知 社会信任 认同偏移 就业模式 劳动强度 角色分工
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襄阳地区不同等级降水的时空特征及主要空间模态
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作者 张玉翠 谭江红 +1 位作者 王培 袁良 《沙漠与绿洲气象》 2026年第1期122-129,共8页
基于1961—2023年襄阳地区7个国家气象观测站逐日降水资料,运用Pearson相关性分析、MannKendall趋势检验法、经验正交函数分析法(EOF),分析襄阳地区不同等级降水的时空特征及主要空间模态。结果表明:1961—2023年,襄阳地区年平均降水量... 基于1961—2023年襄阳地区7个国家气象观测站逐日降水资料,运用Pearson相关性分析、MannKendall趋势检验法、经验正交函数分析法(EOF),分析襄阳地区不同等级降水的时空特征及主要空间模态。结果表明:1961—2023年,襄阳地区年平均降水量和降水日数均呈减小趋势,年平均降水强度呈弱增加趋势;年平均降水量和降水日数减少的重要原因分别为中雨年平均降水量和小雨年平均降水日数减少,而年平均降水强度的增加主要表现为暴雨年平均降水强度的增大。各等级降水量分别与其降水日数具有相似的空间分布;襄阳西南部易发生低强度降水事件,东部易发生高强度降水事件。襄阳地区小雨、中雨、暴雨年平均降水量、降水日数、降水强度的典型空间分布呈整体增多或整体减少;小雨、中雨、大雨年平均降水量、降水日数以及小雨年平均降水强度的次典型分布场为西北部与其他不同区域呈相反的分布,暴雨年平均降水量和降水日数呈东—西反位相分布。 展开更多
关键词 不同等级降水 Mann-Kendall趋势检验 EOF 空间模态
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