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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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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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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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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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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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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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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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Puerto Madero and Porto Maravilha: The Transformation Process of Port Areas into Tourist Zones
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作者 Antonio Colchete Filho Frederico Braida +1 位作者 Lucia Maria Sa Antunes Costa Juliana Varejao Giese 《Journal of Civil Engineering and Architecture》 2017年第10期915-920,共6页
Transformations in the use of urban space in contemporary cities have common features and projects in the global era take similar themes, such as requalifications of port areas and waterfronts. The main objective of t... Transformations in the use of urban space in contemporary cities have common features and projects in the global era take similar themes, such as requalifications of port areas and waterfronts. The main objective of this paper is to revisit the process of urban transformation and valorization of the port areas of Buenos Aires, Argentina, and Rio de Janeiro, Brazil, completed in 1990 and 2015, respectively. It recapitulates their historical processes from decay to recovery as tourist zones, following the implementation of the "Strategic Plan of Antiguo Puerto Madero", from 1990, in Buenos Aires, and of "Urban Operation Porto Maravilha", from 2009, in Rio de Janeiro. While planning and strategies differ as they sought distinct locations in different times, they were similar in attracting massive investment from the real estate market. Therefore, consequences of the projects for the cities and the local population are a more important issue than formal results achieved. 展开更多
关键词 Urban design waterfront renewal puerto Madero Buenos Aires Porto Maravilha Rio de Janeiro.
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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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委内瑞拉PUERTO ORDAZ港纪实
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作者 薛国善 《中国水运(下半月)》 2012年第9期13-14,共2页
为了给即将去委内瑞拉PUERTO ORDAZ港的船长提供些航行和港口信息,作者较详细地总结整理了前段时间的航次经历:从锚地位置、引航技术、航道情况、办关手续、码头作业、地方规矩等等几个方面,期待与同行分享,取长补短。目的是交流经验,... 为了给即将去委内瑞拉PUERTO ORDAZ港的船长提供些航行和港口信息,作者较详细地总结整理了前段时间的航次经历:从锚地位置、引航技术、航道情况、办关手续、码头作业、地方规矩等等几个方面,期待与同行分享,取长补短。目的是交流经验,确保船舶和人员安全,较好地完成航次任务。 展开更多
关键词 委内瑞拉puerto ORDAZ港 航行信息 港口规定
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Seasonal abundance of Pyrodinium bahamense(order Peridiniales,family Gonyaulacaceae)in Mosquito Bay,Vieques,Puerto Rico
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作者 Sharon Grasso Marc Albrecht Mark Martin Bras 《Journal of Coastal Life Medicine》 2016年第4期277-283,共7页
Objective:To determine the presence of consistent spatial or temporal patterns to the abundance of Pyrodinium bahamense(P.bahamense)in Mosquito Bay,Vieques,Puerto Rico.Methods:Measurements of dissolved oxygen,pH,salin... Objective:To determine the presence of consistent spatial or temporal patterns to the abundance of Pyrodinium bahamense(P.bahamense)in Mosquito Bay,Vieques,Puerto Rico.Methods:Measurements of dissolved oxygen,pH,salinity,water temperature,tide level,wind speed,and density counts of P.bahamense were taken at six sites in the bay over approximately one year.The data were analyzed statistically to determine if spatial or temporal patterns were present.Results:There were statistically significant patterns of P.bahamense seasonally,which was similar to other studies done in other subtropical locations with phytoplankton.Also,trends were seen that rain events caused short-term increases in abundance and shallow areas of the bay had lower abundance than that of deeper areas.The average number of organisms from 736 samples was 26.8 per mL.The average water temperature was 29.0℃,the average salinity was 36.8 ppt,the average pH was 8.11,and the average dissolved oxygen level was 4.27 mg/L.Conclusions:The abundance of P.bahamense varies seasonally over shorter time periods.The abundance also varies over a few meters in small coastal bays.This information indicates that economically important bioluminescent bays are vulnerable to changes in freshwater input,water temperature,water circulation patterns and possibly the nutrient inputs from the land surrounding such bays. 展开更多
关键词 Bioluminescent DINOFLAGELLATE puerto Rico Water chemistry MULTIVARIATE
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Determination of the burrow shapes of Cardisoma guanhumi on Vieques,Puerto Rico
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作者 Shannon Sample Marc Albrecht 《Journal of Coastal Life Medicine》 2016年第2期94-97,共4页
Objective:To determine the burrow morphology of Cardisoma guanhumi and to determine if a battery-powered fiber optic camera could be used to investigate these burrows.Methods:A portable fiber optic camera was used to ... Objective:To determine the burrow morphology of Cardisoma guanhumi and to determine if a battery-powered fiber optic camera could be used to investigate these burrows.Methods:A portable fiber optic camera was used to investigate 116 active burrows.All burrows were categorized according to shape.The diameter of each burrow was also recorded and biomass calculations were completed at each study site.Results:Analysis showed that different study sites were more likely to have particular burrow shapes than expected.Three main types of burrows were classified as horizontal slide,short and shallow,and inverted-S.A Pearson Chi-square analysis revealed that burrow shape was not equally distributed across study sites(χ^(2)=61.05,df=18,P<0.0001).Biomass calculations showed that different sized animals inhabited different study sites(ANOVA;df=7,MS=158.3,F=13.9,P<0.0001).The fiber optic camera was useful in determining burrow morphology and occupancy non-destructively.Conclusions:As the locations of juvenile individuals of this species are poorly known,and the species is both ecologically and economically important where it occurs,a greater understanding of burrow morphology and size segregation may help agencies be responsible for managing this natural resource to do so effectively. 展开更多
关键词 Vieques puerto Rico Fiber-optic camera Burrow morphology Cardisoma guanhumi Land crab
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美国岛屿案件发展探析
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作者 张雅迪 《西部学刊》 2024年第16期99-102,141,共5页
岛屿案件是一项具有重大意义的司法裁决,其深远影响体现在对美国领土政策的塑造上,并对美国领土治理方法的形成和持续演进产生了持久的影响。19世纪末和20世纪初,美西战争后,美国获得波多黎各、关岛和菲律宾等领土,岛屿案件随之出现。... 岛屿案件是一项具有重大意义的司法裁决,其深远影响体现在对美国领土政策的塑造上,并对美国领土治理方法的形成和持续演进产生了持久的影响。19世纪末和20世纪初,美西战争后,美国获得波多黎各、关岛和菲律宾等领土,岛屿案件随之出现。这些裁决建立了管理非相邻领土居民的政治地位、权利和义务的法律框架。在岛屿案的审理过程中,美国最高法院就美国主权如何延伸至其获取的领土,以及这些领土上居民所享有的基本权利的宪法解释问题进行了探讨,展示了领土主权和公民权概念的演变。岛屿案件裁决为管理获得的领土的复杂性和平衡国家利益与正义和民主原则提供了有价值的见解。 展开更多
关键词 岛屿案件 波多黎各 领土政策
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某抽水蓄能电站上水库局部防渗渗控分析 被引量:9
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作者 许增光 曹成 +1 位作者 李康宏 柴军瑞 《应用力学学报》 CAS CSCD 北大核心 2018年第2期417-422,共6页
根据实际情况对抽水蓄能电站上库区布设防渗措施,是保证工程效益的重要手段。某抽水蓄能电站上水库在正常蓄水位时各垭口山体薄弱,需布设适当的防渗措施控制库区渗流量。本文根据该工程区资料,建立三维有限元模型,通过反演得到各地层渗... 根据实际情况对抽水蓄能电站上库区布设防渗措施,是保证工程效益的重要手段。某抽水蓄能电站上水库在正常蓄水位时各垭口山体薄弱,需布设适当的防渗措施控制库区渗流量。本文根据该工程区资料,建立三维有限元模型,通过反演得到各地层渗透系数;并分别模拟分析不采取防渗措施时,对各垭口和坝基按不同防渗标准布设防渗帷幕,对全风化层较厚的1号垭口以及靠近坝肩的8号垭口增设防渗墙时等水头线及渗流量的变化。通过对计算结果的对比和分析,选出最优渗控方案,为同类工程提供经验参考。结果表明:防渗墙和防渗帷幕相结合的防渗方式能有效地降低库区渗流量,在坝基以及各垭口处单排布设防渗标准为3Lu的防渗帷幕时,渗控效果显著;相比之下提高防渗标准和增加防渗帷幕排数时等水头线变化不大,渗流量减小量不明显;缩小防渗范围会使垭口处渗流量增大,而增加防渗范围带来的渗流量减小量并不显著。 展开更多
关键词 抽水蓄能电站 上水库防渗 三维渗流场 防渗帷幕和防渗墙 垭口
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试析波多黎各公投的性质及其应用于台湾的限制 被引量:2
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作者 韩克芳 《北京联合大学学报(人文社会科学版)》 CSSCI 2018年第4期100-109,共10页
自1967年至2017年,波多黎各先后就自己的未来政治地位问题进行过五次公投,其重要议题之一就是加入美国,成为其一个州。但不论五次公投的结果如何,美国出于自身利益考量而一直拒绝波多黎各加入。就目前来说,波多黎各与美国的关系虽然不... 自1967年至2017年,波多黎各先后就自己的未来政治地位问题进行过五次公投,其重要议题之一就是加入美国,成为其一个州。但不论五次公投的结果如何,美国出于自身利益考量而一直拒绝波多黎各加入。就目前来说,波多黎各与美国的关系虽然不是纯粹的殖民地与宗主国的关系,但仍带有这种关系的性质。波多黎各公投在根本上是自决性公投,但同时带有民主性公投的特点。有"台独"人士主张将波多黎各模式适用于台湾,声称台湾可以通过公投加入美国或日本,这完全是混淆了波多黎各问题与台湾问题的不同性质,是极为荒谬的言论。 展开更多
关键词 波多黎各 公民投票 “台独公投”
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波多黎各政治身份问题初探 被引量:2
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作者 师嘉林 《武陵学刊》 2017年第5期82-89,共8页
波多黎各政治身份问题由来已久。2012年波多黎各进行了第四次全民公投,其海外自治领的身份进一步强化,而寻求加入美国联邦的计划失败。自1898年以来,美国对波多黎各政治、经济的战略考量是其殖民波多黎各的本质。波多黎各政治身份问题... 波多黎各政治身份问题由来已久。2012年波多黎各进行了第四次全民公投,其海外自治领的身份进一步强化,而寻求加入美国联邦的计划失败。自1898年以来,美国对波多黎各政治、经济的战略考量是其殖民波多黎各的本质。波多黎各政治身份问题的症结在于:波多黎各经济的疲软拖累了其政治身份问题的解决,附庸型经济关系导致其政治民主化进程放缓;波多黎各本土的身份、文化认同以及民族主义运动,对美国管控波多黎各构成强大冲击;美国国会拥有决定波多黎各政治未来的终极单边权力。 展开更多
关键词 波多黎各 美国 政治身份
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墨西哥尤卡坦社会主义运动始末及其成因(1917—1924)
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作者 韩琦 姜玉妍 《上海师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2023年第3期138-152,共15页
1917—1924年,在墨西哥尤卡坦州发生了一场社会主义运动,其所建立的政权被宣布为“美洲的第一个社会主义政权”,运动的领导人费利佩·卡里略·普埃尔托被称为墨西哥社会主义最伟大的推动者。这场运动之所以发生,是因为早期社会... 1917—1924年,在墨西哥尤卡坦州发生了一场社会主义运动,其所建立的政权被宣布为“美洲的第一个社会主义政权”,运动的领导人费利佩·卡里略·普埃尔托被称为墨西哥社会主义最伟大的推动者。这场运动之所以发生,是因为早期社会主义思想在墨西哥得到了传播,玛雅人的村社传统有利于社会主义思想的安家,大革命后尤卡坦的经济结构和社会结构潜藏着革命要求,阿尔瓦拉多将军的前期改革奠定了基础,社会主义政党和“抵抗联盟”组织发挥了先锋作用,费利佩·卡里略·普埃尔托的个人因素至关重要。这场革命虽然为时不长,最终失败,但其促进了当时尤卡坦经济和社会结构的改变,并对卡德纳斯时期的全国改革起到了推动作用。作为社会主义的遗产,它对墨西哥乃至整个拉丁美洲21世纪的社会主义运动仍产生着不朽的影响。 展开更多
关键词 墨西哥 尤卡坦 社会主义运动 费利佩·卡里略 萨尔瓦多·阿尔瓦拉多
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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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