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Simulation of Regional Karst Aquifer System and Assessment of Groundwater Resources in Manatí-Vega Baja, Puerto Rico 被引量:1
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作者 Balati Maihemuti Reza Ghasemizadeh +2 位作者 Xue Yu Ingrid Padilla Akram N. Alshawabkeh 《Journal of Water Resource and Protection》 2015年第12期909-922,共14页
The North Coast karst aquifer system of Puerto Rico, the most productive aquifer of the island, is a vital water source for drinking water and local ecosystems. High freshwater demands alter the coastal groundwater sy... The North Coast karst aquifer system of Puerto Rico, the most productive aquifer of the island, is a vital water source for drinking water and local ecosystems. High freshwater demands alter the coastal groundwater system that impacts both human populations and coastal ecosystems of the island. To predict how this system might respond to rainfall events and high pumping demands, we used the equivalent porous medium (EPM) technique to develop a three-dimensional groundwater flow model to estimate hydrogeological parameters and assess groundwater resources in the Manatí-Vega Baja karst aquifer. The approach is based on the hypothesis that the simplified EPM approach will reproduce groundwater hydrodynamics in this complex karst environment. The steady-state model was calibrated with trial and error and parameter estimation methods using an observed groundwater table of 1995 (r = 0.86, p < 0.0001, n = 39). The large-scale simulation suggested that groundwater flow roughly follows the elevation slope (i.e. south to north). Calibrated hydraulic conductivities range from 0.5 to 86 m/d, whereas the hydro-geologic data strongly suggest higher permeability in the middle karst section of the study area. The transient model adequately estimates the observed groundwater fluctuations in response to rainfall events from 1980 until 2014. The transient results indicate that the conceptual model accuracy is more acceptable with a mean error (ME) of -0.132 m, mean absolute error (MAE) of 0.542 m and root mean square (RMSE) error of 0.365 m. The results of water budget simulation show that the total recharge satisfies the total groundwater withdrawal rate in the past, but continuous closure of more contaminated wells causes groundwater levels to increase in the future. The results indicate that the assumption of applicability of EPM approach is sustained and supported by measured data in the study area. Taking future water demands into account, this model could be applied further to predict the changes of groundwater levels and mass balance under different exploitation scenarios. 展开更多
关键词 KARST AQUIFER GROUNDWATER Modeling Seawater INTRUSION MODFLOW Puerto rico
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Prevalence of refractive errors in children of Puerto Rico 被引量:4
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作者 Héctor C.Santiago Mayra Rullán +5 位作者 Katerin Ortiz Andrés Rivera Mónica Nieves JoséPiña Zulmaris Torres Yvette Mercado 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第3期434-441,共8页
AIM:To determine the prevalence of refractive error in 5-to 17-year-old schoolchildren in Puerto Rico.METHODS:A quantitative descriptive study of 2867 children aged 5 to 17y from all seven educational regions of Puert... AIM:To determine the prevalence of refractive error in 5-to 17-year-old schoolchildren in Puerto Rico.METHODS:A quantitative descriptive study of 2867 children aged 5 to 17y from all seven educational regions of Puerto Rico was conducted from 2016–2019.Refractive error was determined via static and subjective refraction.Children with distance acuity≤20/40 or near visual acuity≤20/32 had a cycloplegic refraction.Data analysis included descriptive statistics,correlation coefficient,Kruskal-Wallis,Chi-square,and t test calculations.RESULTS:Twenty percent of the children had a spherical equivalent refractive error≤-0.50 D,3.2%had a spherical equivalent≥+2.00 D,and 10.4%had astigmatism≥1 D.There was a statistically(but non-clinically)significant myopic change in spherical equivalent refractive error with age(P<0.001).The prevalence of myopia increased with age(P<0.001)but not hyperopia(P=0.59)or astigmatism(P=0.51).Males had a significantly higher hyperopic spherical equivalent than females(P<0.001).Females had a higher prevalence of myopia(P<0.001)than males,but there was no difference in the hyperopia(P=0.74)or astigmatism prevalence(P=0.87).CONCLUSION:The prevalence of a spherical equivalent equal to or less than-0.50 D(myopia,20.7%)is one of the highest among similar-aged children worldwide.Further studies should explore the rate of myopia progression in children in Puerto Rico.Individual children must be monitored to examine the need for treatment of myopia progression. 展开更多
关键词 CHILDREN refractive error Puerto rico MYOPIA HYPEROPIA
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An Assessment of Water Quality Parameters at the Cerrillos Reservoir, Ponce, Puerto Rico in the Aftermath of Hurricane Maria
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作者 Yashira Marie Sánchez-Colón Javier Alejandro Chévere-Del Río +1 位作者 Nichole Marie Sánchez-Guzmán Fred Charles Schaffner 《Journal of Water Resource and Protection》 2022年第1期35-49,共15页
Maintaining the water quality of lakes and reservoirs is part of the 2030 Agenda for Sustainable Development, an initiative promoted by the United Nations, including anthropogenic and natural factors that may influenc... Maintaining the water quality of lakes and reservoirs is part of the 2030 Agenda for Sustainable Development, an initiative promoted by the United Nations, including anthropogenic and natural factors that may influence water quality. The water reservoirs of Puerto Rico were built in watersheds to provide runoff control and for primary uses. The Cerrillos Reservoir is one of the largest water reservoirs in southern Puerto Rico, and is used as a source of potable water and for recreational activities. After hurricane Maria, in September 2017, many communities were without public water service and have obtained their drinking water from local rivers or their tributaries, without filtration or purification treatment. This research explored the physical-chemical parameters of Cerrillos Reservoir’s surface water from May 2018 to January 2019. The objective of the present study is to assess seasonal variations in surface water quality with respect to physical (temperature, turbidity, and conductivity), chemical (nutrient concentrations: (Phosphorus (P) (Soluble Reactive Phosphorus, phosphate, or orthophosphate) and Nitrogen (N) (nitrate, nitrite, and ammonia)), pH, and dissolved oxygen), and biological (total coliforms and <em>Escherichia coli</em>) parameters. Results suggest that Cerrillos Reservoir did not exceed the parameters of temperature, turbidity, conductivity, pH and DO, established by the Puerto Rico Department of Natural and Environmental Resources (PRDNER). The reservoir showed a stable trophic state in relation to inorganic phosphorus and nitrogen as N and P concentrations did not increase sufficiently to disrupt this ecosystem. However, total coliforms exceeded the maximum parameter (23 MPN/100mL - 994 MPN/100mL) established for the Puerto Rico Department of Natural and Environmental Resources and are likely to be the results of the disruption caused by hurricane Maria. 展开更多
关键词 Cerrillos Reservoir Water Quality Puerto rico Post Hurricane Maria
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Perceptions of Climate Change in Puerto Rico before and after Hurricane Maria
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作者 Méndez-Tejeda Rafael María Santos-Corrada Mena Sandra 《American Journal of Climate Change》 2021年第2期153-166,共14页
This article analyzes the perceptions of Puerto Rican citizens of global climate change (GCC) before and after an extreme weather event, specifically Hurricane Maria (HM). The purpose of the current article is to eval... This article analyzes the perceptions of Puerto Rican citizens of global climate change (GCC) before and after an extreme weather event, specifically Hurricane Maria (HM). The purpose of the current article is to evaluate Puerto Ricans’ perceptions of the impact of extreme meteorological phenomena and of GCC before and after HM. This tropical cyclone entered the island as a category IV hurricane on September 17, 2017, causing enormous destruction, loss of life, and economic damage. In this study, two data samples were collected before and after HM struck Puerto Rico (PR) (the second sample was collected approximately six months after the hurricane). Surveyed citizens with general knowledge of GCC increased from 43% to 62%, which the researchers consider a small increase, considering the severe destruction caused by HM. This study also found that Puerto Ricans trust non-profit institutions and the scientific community more than state authorities. Furthermore, 85% of citizens believe that public policies on GCC should be directed by the state (federal, state, and municipal governments);this did not change after HM. In addition, this study found that the poor response of the federal and state governments to the destruction caused by HM increased citizens’ trust in the scientific community. 展开更多
关键词 Puerto rico Hurricane Maria PERCEPTION CLIMATECHANGE
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Prevalence of Gestational Diabetes Mellitus in Puerto Rico: A Study from 2016 to 2021
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作者 Sophia Delgado-Astacio Raymond L. Tremblay Maricarmen Colón-Díaz 《Journal of Diabetes Mellitus》 CAS 2024年第4期194-206,共13页
Background: Gestational diabetes mellitus (GDM) is a temporary form of insulin resistance during pregnancy and is linked to adverse outcomes for both mothers and offspring. Maternal risks include an increased prevalen... Background: Gestational diabetes mellitus (GDM) is a temporary form of insulin resistance during pregnancy and is linked to adverse outcomes for both mothers and offspring. Maternal risks include an increased prevalence of pre-eclampsia, cesarean delivery, and the development of type 2 diabetes within five to ten years post-delivery. For offspring, exposure to elevated maternal glucose levels is associated with macrosomia. A significant challenge in evaluating the prevalence of GDM in Puerto Rico is the lack of recent research quantifying this condition in pregnant women living in Puerto Rico. Objective: This study aimed to estimate the prevalence of Gestational Diabetes Mellitus from 2016 to 2021 by analyzing data collected by Puerto Rico’s Department of Health. Methods: We obtained publicly accessible data from the Division of Children, Mothers, and Adolescents from Puerto Rico’s Department of Health to estimate the prevalence of GDM across the island. Additionally, we correlated the prevalence with socioeconomic, educational, and demographic variables using beta regression models to assess their significance. Results: The prevalence of GDM ranged from 3.2% to 4.5% for the six years studied, with an average prevalence of 3.68%. Regression analysis revealed a significant positive relationship between maternal age and educational level. Higher educational attainment was associated with a reduced risk of GDM, while increasing maternal age was linked to a higher prevalence of the condition. Conclusion: This statistical analysis provides evidence of a steady increase in the prevalence of GDM in Puerto Rico from 2016 to 2021, highlighting the importance of ongoing surveillance and specific interventions to mitigate risk factors. 展开更多
关键词 Gestational Diabetes Mellitus DIABETES Glucose Intolerance Pregnancy in Diabetics Hispanic Women Puerto rico
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Effect of Ambient Temperature on PUF Passive Samplers and PAHs Distribution in Puerto Rico
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作者 Nedim Vardar Ziad Chemseddine Juan Santos 《Computational Water, Energy, and Environmental Engineering》 2013年第2期41-45,共5页
Passive sampling for the monitoring of organic pollutants (PAHs, PCBs, PBDEs) in ambient air has received increased attention in the last two decades. However, the accuracy of the concentration of organics obtained wi... Passive sampling for the monitoring of organic pollutants (PAHs, PCBs, PBDEs) in ambient air has received increased attention in the last two decades. However, the accuracy of the concentration of organics obtained with passive samplers under varying environmental conditions is a subject of controversy. In this study, effect of ambient temperature on passive samplers was evaluated by using three different sampler configurations. Additionally, passive samplers with polyurethane disks (PUF) were applied throughout the Island for the determination of the airborne concentration of polycyclic aromatic hydrocarbons (PAHs). The passive samplers were deployed in seven municipalities for three-month periods in two different sampling campaigns, representing hurricane and non-hurricane seasons. Here we present preliminary results obtained from those sampling campaigns. The total concentrations of 15 PAHs varied from 3.1 to 19.6 and from 5.5 to 38.5 ng/m3 for hurricane and non-hurricane seasons, respectively. Hurricane and non-hurricane season concentrations of PAH were significantly different for the samples taken in the northern municipalities of the Island. However, there was no significant difference in PAH concentrations between the hurricane and non-hurricane seasons for the southern sites. Increased rainfall and high-relative humidity during the hurricane season had an influence on the concentrations of PAHs derived by the passive PUF sampler. 展开更多
关键词 Passive SAMPLER PAH Puerto rico HURRICANE PUF AMBIENT Temperature
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Clinical and Demographic Profile of Women with Uterine Fibroids Living in Puerto Rico
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作者 Edwin Y. Soto-Velázquez Alexander J. Jaramillo-Cañas +7 位作者 Shania N. Aponte-Paris Gabriela V. Martínez-Marrero Irazu S. Guinan Gabrielle A. Rivera-Maldonado Alexandra Novas Pedro L. Cruz-Rosa Idhaliz Flores-Caldera Maricarmen Colón-Diaz 《Open Journal of Obstetrics and Gynecology》 2024年第9期1347-1362,共16页
Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their co... Introduction: Uterine leiomyomas, or fibroids, are prevalent benign tumors affecting up to 70% of reproductive-age women in the United States, significantly impacting productivity and quality of life. Despite their commonality, the epidemiology and clinical patterns of leiomyomas in Puerto Rico remain inadequately researched. Methods: This study conducted a secondary data analysis using clinical, menstrual cycle characteristics, and demographic data from self-administered questionnaires of women undergoing diagnostic laparoscopy for endometriosis in Puerto Rico. Chi-square tests and t-tests analyzed categorical and continuous variables, respectively (p Results: Among 1,610 endometriosis cases, 312 included uterine fibroids. Prevalence estimates were 10.3% (40 years). Primiparous women averaged 22.14 years, with 40.71% having 2 - 3 pregnancies and 26.28% experiencing miscarriages. Symptoms included infertility (29.5%), dyspareunia (40.7%), severe pain (50%), and dysmenorrhea (75.6%). Comorbidities included ovarian cysts (52.2%) and abnormal uterine bleeding (37.8%). Conclusions: Advanced age, parity, and comorbidities like diabetes and hypertension were prevalent in our cohort. Understanding the epidemiological profile of women living in Puerto Rico with uterine fibroids is crucial for improving diagnostic awareness and enhancing patient care. 展开更多
关键词 Uterine Fibroids Puerto rico EPIDEMIOLOGY DYSMENORRHEA Abnormal Uterine Bleeding
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Puerto Rico’s Water Supply: An Investigation of the Levels of Trihalomethanes and Other Contaminants
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作者 Yaritza Jones Wendy Wilburn +1 位作者 Sujata Guha Ryan Beni 《Journal of Geoscience and Environment Protection》 2023年第8期1-21,共12页
The US Commonwealth of Puerto Rico is comprised of 143 islands, atolls, cays, and islets. Of the 143 localities, only 3 islands are inhabited: The mainland (often referenced as Puerto Rico), Culebra, and Vieques. To p... The US Commonwealth of Puerto Rico is comprised of 143 islands, atolls, cays, and islets. Of the 143 localities, only 3 islands are inhabited: The mainland (often referenced as Puerto Rico), Culebra, and Vieques. To properly analyze the water supply quality, the mainland will be the focal point for examining environmental and social injustices. Puerto Rico is a racially diverse but ethnically homogenous territory, with most of the commonwealth living below the poverty level. Access to clean water sources is always tenuous in Puerto Rico. Over 70 percent of the island is served by water, violating US health standards. However, the recent hurricanes made the situation even more detrimental. According to data reported between January 2015 and March 2018 by the Consumer Confidence Report (CCR), 97 percent of the population of Puerto Rico utilizes a common drinking water system with one or more recent violations of the Safe Drinking Water Act for its testing requirements for lead and copper levels. The amounts found were far higher than any US state, meaning that virtually everyone on the island gets water from systems that violated testing or reporting requirements. In this study, we have collected and analyzed the levels of trihalomethanes (THMs), haloacetic acids (HAAs), copper, lead, and total organic compounds (TOCs) in drinking water providing systems in Puerto Rico and compared them with the recommended levels of contaminants provided by the US Environmental Protection Agency (EPA) guidelines. Many of these reported contaminants can have serious and detrimental health effects after prolonged exposure to higher concentrations of the contaminants found in the drinking water sources of Puerto Rico. 展开更多
关键词 Water Quality Social Disparity Puerto rico CONTAMINANTS Household Income Income Per Capita Environmental Justice Hurricane Maria
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The Motivations and Experiences of Young Women in a Microbicide Trial in the USA and Puerto Rico
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作者 Rebecca Giguere Gregory DZimet +5 位作者 Jessica AKahn Curtis Dolezal Cheng-Shiun Leu Marina Mabragana Ian McGowan Alex Carballo-Dieguez 《World Journal of AIDS》 2013年第3期179-186,共8页
Young women are an important target group in microbicide research, yet little is known about why they participate and stay in microbicide trials. Our study examined motivations for participating in a Phase I microbici... Young women are an important target group in microbicide research, yet little is known about why they participate and stay in microbicide trials. Our study examined motivations for participating in a Phase I microbicide trial among 61 women ages 18 - 24 years in the continental USA and Puerto Rico. We also examined their perspectives on study participation. Participants underwent a semi-structured in-depth interview in which they were asked about factors that motivated enrollment and their experiences while participating. They also completed a Web-based Computer Assisted Self Interview in which they were asked to rate study burden (1 = low to 4 = high). Factors that motivated enrollment were altruism (29%), compensation (17%), a combination of altruism and compensation (37%) and free medical exams (17%). Factors that encouraged participants to stay in the study were study staff (95%), confirmation of good health (41%), and the opportunity to learn about their bodies (17%). Mean ratings of study burden ranged from 1.83 (having to travel to site) to 2.41 (colposcopy), indicating that participants were not highly bothered by visits or procedures. Although Phase I trials require invasive procedures, participants were not highly bothered by them and recognized them as necessary. Good relationships with staff and clear information about how procedures contribute to study goals may encourage participants to remain in trials. Young women may be motivated to enter microbicide trials by stressing the role they will play in discovering better HIV-prevention methods and highlighting the comprehensive preventive exams they will receive. 展开更多
关键词 USA Puerto rico MICROBICIDES MOTIVATION Research Participation Young Women HIV
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急性心肌梗死患者复杂病变的预测因素和预后:来自RICO研究的数据
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作者 Rioufol G. Zeller M. +1 位作者 Dentan G. 刘少伟 《世界核心医学期刊文摘(心脏病学分册)》 2007年第11期14-15,共2页
背景:作者旨在探明急性心肌梗死患者中冠状动脉造影可见多个复杂病变(MCL)的决定因素和预后。方法:对1152例在入院后24h内进行冠状动脉造影的连续未经选择的心肌梗死患者进行分析。复杂病变定义为出现血栓、溃疡、不规则斑块和血流受损... 背景:作者旨在探明急性心肌梗死患者中冠状动脉造影可见多个复杂病变(MCL)的决定因素和预后。方法:对1152例在入院后24h内进行冠状动脉造影的连续未经选择的心肌梗死患者进行分析。复杂病变定义为出现血栓、溃疡、不规则斑块和血流受损。具有≤1处复杂病变的患者被认为是单一复杂病变(SCL)患者。 展开更多
关键词 复杂病变 急性心肌梗死患者 rico 预测因素 预后
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神华长焰煤大分子结构特征的研究 被引量:7
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作者 马伦 陆大荣 +4 位作者 梁汉东 朱书全 丁毅 李珊 陈宇飞 《燃料化学学报》 EI CAS CSCD 北大核心 2013年第5期513-522,共10页
利用ASE 350型超声快速溶剂抽提仪,在高温高压下对神华长焰煤(SH)进行二硫化碳/N-甲基吡咯烷酮(CS2/NMP)混合溶剂抽提,抽提率约为25%(质量分数)。将得到的抽提残渣(SHC)进行钌离子催化氧化(RICO)降解反应,并对产物进行了离子色谱(IC)检... 利用ASE 350型超声快速溶剂抽提仪,在高温高压下对神华长焰煤(SH)进行二硫化碳/N-甲基吡咯烷酮(CS2/NMP)混合溶剂抽提,抽提率约为25%(质量分数)。将得到的抽提残渣(SHC)进行钌离子催化氧化(RICO)降解反应,并对产物进行了离子色谱(IC)检测和以四甲基氢氧化铵(TMAH,25%甲醇溶液)为衍生化试剂的热辅助-在线甲酯化后的气质联用仪(GC-MS)检测分析。结果表明,神华长焰煤大分子结构中含有C2~28烷基侧链,C2~22的连接芳环的烷基桥链,有相对较多的醚键链接的芳环结构存在,芳环缩合程度相对较低(主要以含有2~4个苯环的共轭结构为主),有较多的醚键链接的芳环结构及羟基(-OH)、羰基(=C=O)和甲氧基(-OCH3)等形式含氧基团以及含硫和氮等杂原子化合物的存在。 展开更多
关键词 神华长焰煤 溶剂抽提 rico GC—MS
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大港减压渣油超临界萃取残渣极性组分的化学结构特征 被引量:4
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作者 张占纲 郭绍辉 +1 位作者 赵锁奇 闫光绪 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2007年第4期82-88,共7页
将大港减压渣油超临界萃取(SFEF)的残渣利用中性Al2O3色谱柱进行四组分(SARA)分离,得到饱和分、芳香分、胶质和沥青质。然后对其中的芳香分、胶质和沥青质3个极性组分进行钌离子催化氧化反应(RICO)选择性降解,生成的混合物分离处理后,... 将大港减压渣油超临界萃取(SFEF)的残渣利用中性Al2O3色谱柱进行四组分(SARA)分离,得到饱和分、芳香分、胶质和沥青质。然后对其中的芳香分、胶质和沥青质3个极性组分进行钌离子催化氧化反应(RICO)选择性降解,生成的混合物分离处理后,非挥发性羧酸用CH2N2-乙醚溶液酯化,挥发性羧酸用苯甲酰甲基溴酯化。采用GC-MS、GC、FT-IR等手段对这些酯化产物进行定性和定量分析,检测到各组分的降解产物含有一系列的一元正构脂肪酸、α,ω-二元正构脂肪酸和多种芳羧酸,以此可了解各组分的结构特征。结果表明,3个组分的RICO产物中,芳环上的正构烷基侧链含量和连接2个不同芳碳的聚亚甲基桥含量均随着碳链增长呈递减趋势。沥青质组分的芳核中迫位缩合结构比芳香分要多,而芳香分中的联苯和渺位缩合结构比沥青质中的比例要大,胶质中各种结构的分布介于两者之间。 展开更多
关键词 超临界萃取残渣 极性组分 钌离子催化氧化(rico) 化学结构
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美国FICO评分系统述评 被引量:32
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作者 姜琳 《商业研究》 北大核心 2006年第20期81-84,共4页
作为个人信用评估事实上的标准,FICO评分系统在美国得到广泛地使用。FICO评分系统有五类主要影响因素:客户的信用偿还历史、信用账户数、使用信用的年限、正在使用的信用类型、新开立的信用账户。这五类因素有不同的权重,每类因素中又... 作为个人信用评估事实上的标准,FICO评分系统在美国得到广泛地使用。FICO评分系统有五类主要影响因素:客户的信用偿还历史、信用账户数、使用信用的年限、正在使用的信用类型、新开立的信用账户。这五类因素有不同的权重,每类因素中又包括若干子项。 展开更多
关键词 FICO评分系统 个人信用 评分因素
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Application Effects of Photosynthesis Synergist in Early Hybrid Rice
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作者 徐优 王学华 +1 位作者 邱启生 申斌 《Agricultural Science & Technology》 CAS 2015年第5期880-882,共3页
In order to explore the application effect of Yezhiyuan in early hybrid rice,Liangliangyou No.211 and Lingliangyou No.268 were tested in a teaching base in Hunan Agricultural University and Xidu Town, Hengyang County,... In order to explore the application effect of Yezhiyuan in early hybrid rice,Liangliangyou No.211 and Lingliangyou No.268 were tested in a teaching base in Hunan Agricultural University and Xidu Town, Hengyang County, with Yezhiyuan.The test results showed that the application of photosynthesis synergist in later tillering stage would increase the content of chlorophyll of functional leaf and photosynthetic rate, reduce transpiration rate and enhance yield per unit area. With Yezhiyuan applied, both of photosynthetic rate and chlorophyll content kept higher compared with control group in two experimental sites, and practical yield in Hunan Agricultural University grew 8.54% higher compared with control group, and 10.67%in Hengyang. 展开更多
关键词 Early hybrid rico Yezhiyuan Photosynthesis synergist Application effect
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基于Ajax的门户框架的研究与实现 被引量:1
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作者 王前 刘勇 《微电子学与计算机》 CSCD 北大核心 2008年第11期47-51,共5页
提出了一种基于Ajax的门户框架设计方案.详细分析了该方案设计的门户框架的体系结构和组成模块以及模块之间的关系,并利用Spring MVC和一种Ajax库Rico实现了该方案.工程实践表明,采用该方案设计的门户框架系统,层次结构清晰,代码复用率... 提出了一种基于Ajax的门户框架设计方案.详细分析了该方案设计的门户框架的体系结构和组成模块以及模块之间的关系,并利用Spring MVC和一种Ajax库Rico实现了该方案.工程实践表明,采用该方案设计的门户框架系统,层次结构清晰,代码复用率高,并能有效地提高门户系统的运行效率及改善用户的交互体验. 展开更多
关键词 门户框架 AJAX SPRING MVC rico
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海洋球石藻(Emiliania huxleyi)通用表达载体的构建与电转化
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作者 王薛婷 郭强强 +3 位作者 蔡艺钦 陈志福 李健 刘静雯 《海洋学报》 CAS CSCD 北大核心 2016年第8期103-114,共12页
海洋球石藻Emiliania huxleyi是一种全球广泛分布的真核浮游植物,该种不仅是海洋碳、硫循环和全球气候变化的重要指示物种,而且能够产生丰富的次级代谢生物活性物质,在生物技术领域也具有很好的应用前景。本文通过分析氨苄青霉素、卡那... 海洋球石藻Emiliania huxleyi是一种全球广泛分布的真核浮游植物,该种不仅是海洋碳、硫循环和全球气候变化的重要指示物种,而且能够产生丰富的次级代谢生物活性物质,在生物技术领域也具有很好的应用前景。本文通过分析氨苄青霉素、卡那霉素、G418、氯霉素、链霉素、新生霉素及嘌呤霉素等7种常用抗生素对海洋球石藻生长的影响,确定G418可作为该藻阳性转化藻株的抗性筛选试剂,其对应的抗性基因neo则作为该藻表达载体构建中的抗性筛选标记。在此基础上克隆了绿色荧光蛋白基因gfp、抗性标记基因neo及E.huxleyi BOF92内源性岩藻黄素-叶绿素a/c结合蛋白基因的启动子fcp,以pUC18为基础载体,构建了pUC18-fcp-gfp和pUC18-fcp-neo两个重组表达载体,以电转化方法共转化球石藻细胞并结合选择性固体培养基筛选,成功获得了被转化的球石藻细胞。海洋球石藻遗传转化系统的建立为进一步开展该种相关的基础生物学研究及其在生物技术领域的应用奠定了基础。 展开更多
关键词 海洋球石藻 通用表达载体 rico标记基因 电转化
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Evaluating COVID-19’s impacts on Puerto Rican’s travel behaviors 被引量:1
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作者 Lauren C.Carter Ran Tao 《Geo-Spatial Information Science》 SCIE EI CSCD 2023年第4期616-626,共11页
The COVID-19 pandemic has completely disrupted and possibly permanently changed the way humans travel.In Puerto Rico,major travel restrictions to the island have persisted at different levels since March 2020,which he... The COVID-19 pandemic has completely disrupted and possibly permanently changed the way humans travel.In Puerto Rico,major travel restrictions to the island have persisted at different levels since March 2020,which heavily influenced residents’travel behaviors.However,it remains unclear about how big the impact is and how inequitable it might be.The goal of this study is to evaluate COVID-19’s impacts on Puerto Rican’s travel behaviors by analyzing travel flows from Puerto Rico to the contiguous US with a modified gravity model.The roles of socioeconomic factors regarding the Puerto Rican travelers and COVID-19 factors regarding the destination US states have been assessed.COVID-19 was a strong deterring factor of travel at the beginning of the pandemic and also in the winter of 2020,but it did not keep Puerto Ricans from traveling during the summer 2020 when most travel restrictions were lifted.We found that the elderly population of Puerto Rico,despite being more vulnerable to COVID-19,were much more likely to travel during the pandemic.We also found that,during the holiday season in 2020,some socioeconomically disadvantaged populations were more likely to be traveling,a direct contradiction to their travel flows the year prior.These findings shed light on about how disproportionately affected populations behavior changed from pre-pandemic to after the pandemic started.With the continuance of the pandemic,this information is extremely valuable for future planning with respect to emergency management,travel regulation,and social benefit. 展开更多
关键词 COVID-19 Puerto rico travel behavior social vulnerability human mobility
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Effect of Particle Size and Pesticide Contamination on Preference and Ingestion Rates by the Tropical Freshwater Shrimp Xiphocaris elongata
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作者 Wesley X. Torres-Pérez Omar Pérez-Reyes 《Open Journal of Ecology》 2023年第4期183-198,共16页
In tropical streams, freshwater shrimp are essential to preserve the structure and function of lotic ecosystems. Shredder shrimp play a fundamental role in organic matter decomposition because these feed on detritus. ... In tropical streams, freshwater shrimp are essential to preserve the structure and function of lotic ecosystems. Shredder shrimp play a fundamental role in organic matter decomposition because these feed on detritus. In addition, they are especially important organisms as they connect all trophic levels at food webs. In natural environments, decaying leaf material may accumulate contaminants, including insecticides and herbicides. At these, shredder shrimp can be exposed to these contaminants through ingestion of leaf litter material. The objectives of this study were to evaluate if the shredder shrimp Xiphocaris elongata display a preference for feeding on different plant species and leaf size areas while also assessing their consumption of leaves contaminated with pesticides. We also evaluated acetylcholinesterase (AChE) activity as a possible biomarker of pesticide contamination using an immunofluorescence and microscopy imaging approach. Our results revealed that the leaf area and plant species more appropriate for future toxicological studies is Spathodea campanulata leaves, with a leaf area of 0.65 cm<sup>2</sup>. This study also showed that sublethal concentrations of malathion and permethrin in leaves seem to have a significant effect on the ingestion rates of X. elongata, which suggests that the presence of these contaminants influenced feeding behavior. Immunofluorescence in cephalothorax ganglia showed a decline in AChE activity when the sublethal dose of malathion and permethrin increased. The observed results suggest that AChE activity can be used as a biomarker to detect and assess permethrin and malathion exposure on shredder shrimp. 展开更多
关键词 MALATHION PERMETHRIN PESTICIDE Puerto rico Spathodea TOXICOLOGY
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无人机灾情应急响应系统 被引量:1
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作者 左先旺 《电子测试》 2019年第11期79-81,共3页
本文设计了一个无人机灾情应急响应系统,能够针对灾害破坏情况快速的进行应急救援响应。对受灾地区进行医疗包补给和主要道路受损情况侦察。以美国2017年波多黎各岛发生的海啸为例,根据波多黎各岛的主要交通网络以及人口分布密度。建立... 本文设计了一个无人机灾情应急响应系统,能够针对灾害破坏情况快速的进行应急救援响应。对受灾地区进行医疗包补给和主要道路受损情况侦察。以美国2017年波多黎各岛发生的海啸为例,根据波多黎各岛的主要交通网络以及人口分布密度。建立了包含45个节点和60条路线的加权交通网络模型,并结合各类型无人机的续航能力和搭载医疗物资能力,利用最小生成树、改善的Floyd-Warshall算法等。确定该灾情应急响应系统中无人机的类型及数量,以及不同无人机的续航路线,能够在最短的时间内完成医疗物资运送以及道路侦察任务。 展开更多
关键词 无人机灾情应急响应系统 波多黎各岛海啸 最小生成树 Floyd-Warshall算法
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Assessing Healthcare Facilities Preparedness for Mass Fatalities Incident
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作者 Marisol Pena-Orellana Ralph Rivera-Gutierrez +5 位作者 Juan AGonzalez-Sanchez Nilsa Padilla-Elias Heriberto Marin Centeno Hector Alonso-Serra Liza Millan-Perez Patricia Monserrate-Vazquez 《International Journal of Clinical Medicine》 2013年第12期525-531,共7页
Background: Any healthcare facility must be prepared to handle a dramatic increase in deaths that can be produced by a catastrophic disaster. A mass fatality incident (MFI) will significantly increase the usual number... Background: Any healthcare facility must be prepared to handle a dramatic increase in deaths that can be produced by a catastrophic disaster. A mass fatality incident (MFI) will significantly increase the usual number of deaths that hospitals or forensic science services can manage on a daily basis. A survey was conducted to assess the hospital emergency department level of preparedness to deal with an MFI. Objective: To examine healthcare facilities level of preparedness for an MFI and morgue capacity. Methods: A total of 39 out of a sample of 44 hospitals participated in the study. Seven questionnaires were administered to explore: hospital general characteristics;emergency plans;equipment and infrastructure;collaborative agreements;personnel trainings;emergency communications;laboratory facilities;treatment protocols;security;and, epidemiologic surveillance. Results: Three-fourths (79.5%) of the healthcare facilities reported having a morgue, their average storage capacity was of three bodies. More than two-thirds (66.7%) of the institutions stated that they could not increase their morgue’s capacity. Most installations without a morgue do not possess an agreement with any other institution for the management of bodies. Hospitals have a very limited number of body bags utilized for the handling and transport of bodies. Conclusion: Most of healthcare facilities have morgues, but there are limitations with the current capacity and the lack of resources to increase their capacity in case of a disaster. Management of an MFI must be part of every hospital’s emergency plan, and must include collaborative agreements with forensic authorities, emergency management and public health agencies, and the community. 展开更多
关键词 Hospitals Morgues Mass Casualties Mass Fatalities Puerto rico
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