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Comprehensive Analysis of Cancer Incidence and Mortality Trends in Costa Rica: Implications for Public Health
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作者 Guzman Percy 《Journal of Cancer Therapy》 2024年第5期219-221,共3页
This commentary delves into the evolving landscape of cancer incidence and mortality in Costa Rica, presenting a comprehensive analysis of the data. Key findings reveal a concerning upward trajectory in cancer inciden... This commentary delves into the evolving landscape of cancer incidence and mortality in Costa Rica, presenting a comprehensive analysis of the data. Key findings reveal a concerning upward trajectory in cancer incidence rates, placing Costa Rica at the forefront within Central America. While prostate cancer and breast cancer dominate, disparities emerge when scrutinizing gender-specific trends. Notably, stomach and cervical cancers show declines, potentially attributed to targeted interventions. However, colorectal and liver cancers witness mortality increases, necessitating strategic responses. Geographical disparities persist across provinces, highlighting the need for equitable healthcare access. In conclusion, this commentary underscores the urgency of addressing the burgeoning cancer burden in Costa Rica, calling for evidence-based interventions and collaborative efforts on a global scale. 展开更多
关键词 Cancer Incidence Cancer Mortality Costa rica Cancer Trends Risk Factors Early Detection Public Health
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布氏杆菌Ⅳ型分泌系统相关蛋白基因RicA的克隆、原核表达及免疫原性分析 被引量:2
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作者 韩玉霞 孙志华 +3 位作者 刘娟 关团 张辉 陈创夫 《西北农业学报》 CAS CSCD 北大核心 2015年第5期18-23,共6页
为克隆并原核表达布氏杆菌(Brucella melitensis)疫苗菌株M5Ⅳ型分泌系统相关蛋白基因RicA,并进行表达蛋白的免疫原性分析,应用PCR技术从布氏杆菌疫苗菌株M5全基因组扩增RicA基因片段,亚克隆至pMD18-T载体后测序分析,构建重组表达载体pE... 为克隆并原核表达布氏杆菌(Brucella melitensis)疫苗菌株M5Ⅳ型分泌系统相关蛋白基因RicA,并进行表达蛋白的免疫原性分析,应用PCR技术从布氏杆菌疫苗菌株M5全基因组扩增RicA基因片段,亚克隆至pMD18-T载体后测序分析,构建重组表达载体pET-28a(+)-RicA,转化E.coli BL21(DE3)表达菌,以不同浓度IPTG诱导表达不同时间,SDS-PAGE鉴定表达效果,表达蛋白经AKTA蛋白纯化系统纯化,用Antheprot 5.0软件分析其理化特性及抗原性,Western Blot检测其免疫原性。结果表明:RicA基因全长528bp,编码175个氨基酸,与基因库中已知菌株的核苷酸同源性和氨基酸同源性均达到99%以上。SDS-PAGE表明,RicA融合蛋白在大约23ku处出现条带,纯化后条带单一。软件分析发现RicA蛋白融合抗原性较强,Western Blot检测证明其有较好的免疫原性。说明,成功克隆并表达布氏杆菌疫苗菌株M5 RicA基因,为进一步研究其与布氏杆菌Ⅳ型分泌系统及布氏杆菌致病机制之间的关系奠定了基础。 展开更多
关键词 布氏杆菌 Ⅳ型分泌系统 rica基因
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Wood Physical and Mechanical Properties of Populus × canadensis Moench and Populus ×euramericana(Dode) Guinier cv. Gelrica
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作者 张英杰 冯德君 窦延光 《Agricultural Science & Technology》 CAS 2017年第12期2532-2535,共4页
The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and eff... The physical-mechanical properties of Populus x canadensis Moench and Populus x euramericana (Dode) Guinier cv. Gelrica were studied to provide theoret- ical and scientific bases for the directional breeding and efficient use of artificial forests with P. canadensis and P. euramericana Gelrica. The results showed the air-dried density, basic density of P. canadensis were 0.468 g/cm3 and 0.372 g/cm3, respectively; the shrinkage coefficient of radial, tangential and volume were 0.133%, 0.270% and 0.553%, respectively;the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 302.99 MPa, 79.69 MPa and 40.32 Mpa, respectively. As for the P. euramericana Gelrica, the air-dried density, basic densitywere 0.453 and 0.355 g/cm3, respectively; the shrink- age coefficient of radial, tangential and volume were 0.205%, 0.304% and 0.554%, respectively; the modulus of elasticity in static bending, the bending strength and the compressive strength parallel to grain were 9 014.44, 55.87 and 33.09 Mpa respectively. Comprehensive analysis of the indicators showed that the properties of P. canadensis were better than those of P.euramericana Gelrica. 展开更多
关键词 Populus x canadensis Moench Populus x euramericana (Dode) Guiniercv. Ge/rica Physical properties Mechanical properties
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Role of bacterial and genetic factors in gastric cancer in Costa Rica 被引量:9
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作者 Sergio A Con Hiroaki Takeuchi +3 位作者 Gil R Con-Chin Vicky G Con-Chin Nobufumi Yasuda Reinaldo Con-Wong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第2期211-218,共8页
AIM: To evaluate several risk factors for gastric cancer (GC) in Costa Rican regions with contrasting GC incidence rate (GCIR). METHODS: According to GCIR, 191 Helicobacter pylori (H pylori)-positive patients ... AIM: To evaluate several risk factors for gastric cancer (GC) in Costa Rican regions with contrasting GC incidence rate (GCIR). METHODS: According to GCIR, 191 Helicobacter pylori (H pylori)-positive patients were classified into groups A (high GCIR, n = 101) and B (low GCIR, n = 90). Human DNA obtained from biopsy specimens was used in the determination of polymorphisms of the genes coding for interleukin (IL)-1β and IL-10 by PCRRFLP, and IL-1RN by PCR. H pylori DNA extractions obtained from clinical isolates of 83 patients were used for PCR-based genotyping of H pylori cagA, vacA and babA2. Human DNA from gastric biopsies of 52 GC patients was utilized for comparative purposes. RESULTS: Cytokine polymorphisms showed no association with GCIR variability. However, gastric atrophy, intestinal metaplasia and strains with different vacA genotypes in the same stomach (mixed strain infection) were more frequently found in group A than in group B, and cagA and vacA s1b were significantly associated with high GCIR (P = 0.026 and 0.041, respectively). IL- 1β+3954_T/C (OR 2.1, 1.0-4.3), IL-1RN^*2/L (OR 3.5, 1.7-7.3) and IL-10-592_C/A (OR 3.2, 1.5-6.8) were individually associated with GC, and a combination of these cytokine polymorphisms with Hpylori vacA slb and ml further increased the risk (OR 7.2, 1.4-36.4). CONCLUSION: Although a proinflammatory cytokine genetic profile showed an increased risk for developing GC, the characteristics of Hpylori infection, in particular the status of cagA and vacA genotype distribution seemed to play a major role in GCIR variability in Costa Rica. 展开更多
关键词 Costa rica Gastric cancer HELICOBACTERPYLORI Host genetic factors
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Clinical relevance of Helicobacter pylori babA2 and babA2/B in Costa Rica and Japan 被引量:3
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作者 Sergio A Con Hiroaki Takeuchi +4 位作者 Mitsuaki Nishioka Norihito Morimoto Tetsuro Sugiura Nobufumi Yasuda Reinaldo Con-Wong 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第4期474-478,共5页
AIM:To evaluate the prevalence of Helicobacter pylori(H.pylori ) babA2 ,babB and a recombinant gene between babA2 and babB(babA2/B ),and their role in the development of atrophic gastritis in Costa Rican and Japanese ... AIM:To evaluate the prevalence of Helicobacter pylori(H.pylori ) babA2 ,babB and a recombinant gene between babA2 and babB(babA2/B ),and their role in the development of atrophic gastritis in Costa Rican and Japanese clinical isolates.METHODS:A total of 95 continuous H.pylori-positive Costa Rican(41 males and 54 females;mean age,50.65 years;SD,± 13.04 years) and 95 continuous H.pylori-positive Japanese(50 males and 45 females;mean age,63.43;SD,± 13.21 years) patients underwent upper endoscopy from October 2005 to July 2006.They were enrolled for the polymerase chain reaction(PCR)-based genotyping of the H.pylori babA2 ,babB and babA2/B genes.Statistical analysis was performed using the χ2 test and the Fisher's exact probability test and multivariate analysis was performed by logistic regression adjusting for gender and age.P < 0.05 was regarded as statistically significant.RESULTS:The PCR-based genotyping of 95 Costa Rican and 95 Japanese isolates showed a higher prevalence of babA2 in Japan(96.8%) than in Costa Rica(73.7%),while that of babA2/B was higher in Costa Rica(11.6%) than in Japan(1.1%).In Costa Rican isolates only,babA2 was significantly associated with atrophic gastritis(P = 0.01).CONCLUSION:These results suggest that the status of babA2 and babA2/B shows geographic differences,and that babA2 has clinical relevance in Costa Rica. 展开更多
关键词 BABA2 babA2/B Costa rica Helicobacter pylori JAPAN
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Fishery Biology of Jumbo Flying Squid Dosidicus gigas off Costa Rica Dome 被引量:4
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作者 CHEN Xinjun LI Jianghua +2 位作者 LIU Bilin LI Gang LU Huajie 《Journal of Ocean University of China》 SCIE CAS 2014年第3期485-490,共6页
The jumbo flying squid(Dosidicus gigas) population was surveyed with the help of Chinese squid jigging vessels off the Costa Rica Dome(4°–11°N, 90°–100°W) in 2009 and 2010. The daily catch of D. ... The jumbo flying squid(Dosidicus gigas) population was surveyed with the help of Chinese squid jigging vessels off the Costa Rica Dome(4°–11°N, 90°–100°W) in 2009 and 2010. The daily catch of D. gigas in the two survey cruises ranged from 0 to 5.5 t and was mostly obtained from the areas bounded by 6°–9°N and 91°–94°W and by 6°30′–7°30′N and 96°–97°W. The sea surface temperature in the areas yielding the most catch ranged from 27.5 to 29℃. The sex ratio of the total catch was 3.75:1(female: male). The mantle length of the squid ranged from 211 to 355 mm(male) and from 204 to 429 mm(female) with an average of 297.9 and 306.7 mm, respectively. In the relationship of the mantle length(mm) and body weight(g) of the squid, there was no significant difference between sexes. The female and male were at a similar maturity, and most individuals are maturing or have matured with a few females being spent. The size(mantle length) and age at the first sexual maturity were 297 mm and 195 d in females, and less than 211 mm and 130 d in males, respectively. Most of the sampled stomachs(70.6%) had no food remains. The major preys of the squids were fish, cephalopods and crustaceans, with the most abundant Myctophum orientale and D. gigas. The preys in more than 65% of the non-empty sampled stomachs evidenced the cannibalism of D. gigas. The results improved current understanding of the fishery biology of D. gigas off the Costa Rica Dome, which may facilitate the assessment and management of relative fishery resources. 展开更多
关键词 Dosidicus gigas fishery biology Costa rica Dome
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Sub-Canopy Temperature Dynamics of a Native Tree Plantation from a Lowland Tropical Rainforest in Costa Rica 被引量:1
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作者 Traci-Lynn Hirai Víctor D. Carmona-Galindo +2 位作者 Stacie Samuelson Cherie Hale Elizabeth Braker 《Open Journal of Forestry》 2014年第3期191-196,共6页
With urbanization encroaching upon forestlands, characterizing microclimates in secondary forests will be important for the sustainable management of microclimates in agroforestry systems. We used micro-sensors to cha... With urbanization encroaching upon forestlands, characterizing microclimates in secondary forests will be important for the sustainable management of microclimates in agroforestry systems. We used micro-sensors to characterize changes in temperature at different heights in the sub-canopy of both secondary forest and 15-year-old agroforestry plots. Results show that while agroforestry plots had different temperature profiles from the secondary forest, the monoculture plot (consisting of Pentaclethra macroloba) had temperatures similar to the profile found in the secondary forest. This suggests that the replication of temperature profiles in a secondary forest may be independent of the number of tree species in a plot (e.g. polyculture), but may instead depend on the density of a given trees species. These findings further suggest that characterizing temperature microclimates in secondary forests can serve to improve the ecological sustainability of agro-forestry systems. 展开更多
关键词 AGROFORESTRY CANOPY Microclimates Costa rica La SELVA Biological Station SUCCESSION
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New Records of Marine Macroalgae on the Caribbean on Coast of Costa Rica
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作者 Rubén Cabrera Jhoana Díaz-Larrea Schery Umanzor 《American Journal of Plant Sciences》 2019年第10期1708-1728,共21页
The results obtained in this study highlight that further the macroalgae diversity in this region is even higher than what is reported to date. Here we present eight new records of marine macroalgae collected from the... The results obtained in this study highlight that further the macroalgae diversity in this region is even higher than what is reported to date. Here we present eight new records of marine macroalgae collected from the Caribbean coast of Costa Rica between March 2011 and May 2019. The morphological characteristics of Bryocladia cuspidata, Ceratodictyon variabile, Gracilaria hayi, Padina boergesenii, Zonaria tournefortii, Sargassum furcatum, Chaetomorpha aerea, and Bryopsis pennata var. secunda are described. The genera Bryocladia and Zonaria are reported for the first time for this region. 展开更多
关键词 NEW RECORDS Caribbean SEA Costa rica
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<i>Kappaphycus alvarezii</i>(Rhodophyta): New Record of an Exotic Species for the Caribbean Coast of Costa Rica
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作者 Rubén Cabrera Schery Umanzor +1 位作者 Jhoana Díaz-Larrea Patricia G. Araújo 《American Journal of Plant Sciences》 2019年第10期1888-1902,共15页
Kappaphycus alvarezii, a red macroalgal species native to South-East Asia, has been introduced for commercial purposes to more than 20 tropical countries. In 2000, Panama became the first Central American country to d... Kappaphycus alvarezii, a red macroalgal species native to South-East Asia, has been introduced for commercial purposes to more than 20 tropical countries. In 2000, Panama became the first Central American country to develop its cultivation following a pilot-commercial approach. Twelve years after his introduction to Panama, the species was found to the south Caribbean coast. In the present study, we report the first record of K. alvarezii collected in Costa Rican waters. Genetic identification of the sample was performed with the mitochondrial marker cox2-cox3 intergenic spacer, and phylogenetic analyses showed that the sample collected grouped into a monophyletic clade with GenBank sequences from Vietnam, Indonesia, the Philippines, Brazil and Venezuela. Here we provide further description of its position with respect to other strains of K. alvarezii collected globally. Its possible route of entry to the Caribbean coast of Costa Rica is discussed. To date, it is possible to locate K. alvarezii in different areas away from the production fields which show its dispersion, and that the species is expanding;but more studies are needed to know the phase of colonization in which it is located because it is a combination of natural factors and human exploitation that determines the invasive potential of the species. 展开更多
关键词 Carrageenophytes CULTIVATION Costa rica Dispersion EXOTIC Introduction
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Salt/Sodium Intake Estimation in Children and Adolescents of Costa Rica
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作者 Hilda Núñez-Rivas Ileana Holst-Schumacher +3 位作者 Adriana Blanco-Metzler María de los Angeles Montero-Campos Natalia Campos-Saborío Karla Benavides-Aguilar 《Food and Nutrition Sciences》 2020年第10期919-941,共23页
The objectives of this study were to estimate sodium intake and to identify the main dietary sources of this nutrient in young people. Cross-sectional study performed in 2685 students from 64 schools and high-schools ... The objectives of this study were to estimate sodium intake and to identify the main dietary sources of this nutrient in young people. Cross-sectional study performed in 2685 students from 64 schools and high-schools of Costa Rica. A food frequency survey was applied to study the food and beverage intake habits of the participants. The average daily sodium intake for children and adolescents 7 to 18 years of age was 3214 mg. Around 97% of the students had sodium intakes > 2300 mg per day with significant differences by age subgroup, sex and nutritional status due to excess body weight (p < 0.001). The average sodium density of the diet was 1698 mg sodium/1000kcal, and the average addition of salt to the food was 445 mg of sodium (1.1 grams of salt). Including the amount added to the served food, the average sodium intake for children and adolescents from 7 to 18 years of age increased to 3434 mg and the overall average sodium density increased to 1821 mg of sodium/1000kcal, maintaining significant differences by age subgroups (p < 0.001). These results justify carrying out social marketing campaigns that include educational processes with sense and meaning for children, adolescents and families, in such a way that these groups of the population become motivated to modify gradually their eating habits, such as reducing the use of sauces, seasonings and salt in food preparation and at the table. If the habit of adding salt to the served food is gradually reduced or avoided, the children and adolescents in Costa Rica could decrease the intake of salt per day from 1 to 2 grams. This decrease could be even more effective if youngsters additionally would remove the intake of sauces, contributing in this way to achieve the maximum salt intake recommendation (5 g per day). 展开更多
关键词 SALT Sodium Intake CHILDREN Adolescents Costa rica
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Violent and Risk-Taking Behaviors Associated with Intake of Energy Drinks Mixed with Alcohol and Perceptions of This Consumption among Children and Adolescents in Costa Rica
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作者 Núñez-Rivas Hilda Holst-Schumacher Ileana Campos-Saborío Natalia 《Food and Nutrition Sciences》 2020年第8期836-853,共18页
<b><span style="font-family:Verdana;">Introduction:</span></b><b><span style="font-family:;" "=""> </span></b><span style="fon... <b><span style="font-family:Verdana;">Introduction:</span></b><b><span style="font-family:;" "=""> </span></b><span style="font-family:;" "=""><span style="font-family:Verdana;">The consumption of energy drinks and its mix with alcohol has been associated with negative and violent behaviors in youngsters. </span><b><span style="font-family:Verdana;">Objective:</span></b> </span><span style="font-family:Verdana;">To </span><span style="font-family:Verdana;">determine the risk-taking behaviors associated with the consumption of energy drinks mixed with alcohol</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">in Costa Rican adolescents. </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> A mixed cross-sectional study was performed with a population of 2667 students of 64 educative centers in 2016. Descriptive statistics were performed with the program SPSS 20.0 and a value of p <</span></span><span> </span><span style="font-family:Verdana;">0.05 was considered significant. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> The third part of the study population is usually a consumer of energy drinks (30%) and 3% make use of drinks mixed with alcohol.</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><span style="font-family:Verdana;">The children and adolescents, who consume energy-alcohol mixed drinks, are more likely to present risk-taking behaviors than those who do not consume these mixed beverages: combined use of medicines to get high;cocaine consumption, consumption of cement/glue, consumption of marijuana, physical violence (fighting), use of weapons, suicidal ideation, deliberate self-harm, low educational expectation, sexual intercourses, cyberbullying and school apathy. The students perceived the intake of energy beverages as of low risk for their health. They also agree that frequent consumption is because drinks have good flavors and nice logo designs and the ability to stay awake and with more energy for longer periods of time in order to improve in academic homework, sports performance and to endure more the consumption of alcoholic beverages. </span><b><span style="font-family:Verdana;">Conclusions: </span></b><span style="font-family:Verdana;">Public health policies should consider controlling the publicity aimed to children and adolescents regarding the marketing of energy and alcoholic drinks.</span></span> 展开更多
关键词 Energy Drinks Energy-Alcohol Mix Drinks Children Adolescents Costa rica
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Spatial and Temporal Variation of Stable Isotopes in Precipitation across Costa Rica: An Analysis of Historic GNIP Records
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作者 Ricardo Sánchez-Murillo Germain Esquivel-Hernández +4 位作者 Kristen Welsh Erin S. Brooks Jan Boll Rosa Alfaro-Solís Juan Valdés-González 《Open Journal of Modern Hydrology》 2013年第4期226-240,共15页
The location of Costa Rica on the Central American Isthmus creates unique microclimate systems that receive moisture inputs directly from the Caribbean Sea and the Pacific Ocean. In Costa Rica, stable isotope monitori... The location of Costa Rica on the Central American Isthmus creates unique microclimate systems that receive moisture inputs directly from the Caribbean Sea and the Pacific Ocean. In Costa Rica, stable isotope monitoring was conducted by the International Atomic Energy Agency and the World Meteorological Association as part of the worldwide effort entitled Global Network of Isotopes in Precipitation. Sampling campaigns were mainly comprised of monthly-integrated samples during intermittent years from 1990 to 2005. The main goal of this study was to determine spatial and temporal isotopic variations of meteoric waters in Costa Rica using historic records. Samples were grouped in four main regions: Nicoya Peninsula (d2H = 6.65d18O -0.13;r2 = 0.86);Pacific Coast (d2H = 7.60d18O + 7.95;r2 = 0.99);Caribbean Slope (d2H = 6.97d18O + 4.97;r2 = 0.97);and Central Valley (d2H = 7.94d18O + 10.38;r2 = 0.98). The water meteoric line for Costa Rica can be defined as d2H = 7.61d18O + 7.40 (r2 = 0.98). The regression of precipitation amount and annual arithmetic means yields a slope of ﹣1.6‰ d18O per 100 mm of rain (r2 = 0.57) which corresponds with a temperature effect of ﹣0.37‰ d18O/°C. A strong correlation (r2 = 0.77) of ﹣2.0‰ d18O per km of elevation was found. Samples within the Nicoya Peninsula and Caribbean lowlands appear to be dominated by evaporation enrichment as shown in d-excess interpolation, especially during the dry months, likely resulting from small precipitation amounts. In the inter-mountainous region of the Central Valley and Pacific slope, complex moisture recycling processes may dominate isotopic variations. Generally, isotopic values tend to be more depleted as the rainy season progresses over the year. Air parcel back trajectories indicate that enriched isotopic compositions both in Turrialba and Monteverde are related to central Caribbean parental moisture and low rainfall intensities. Depleted events appear to be related to high rainfall amounts despite the parental origin of the moisture. 展开更多
关键词 Stable ISOTOPES Costa rica PRECIPITATION GNIP HYSPLIT Model
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Carbon Footprint across the Coffee Supply Chain: The Case of Costa Rican Coffee
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作者 Bernard Killian Lloyd Rivera +1 位作者 Melissa Soto David Navichoc 《Journal of Agricultural Science and Technology(B)》 2013年第3期151-170,共20页
The issue of carbon emissions has been on the corporate sustainability agenda for some years. For those working in agricultural supply chains, the challenges remain significant, given the diverse direct and indirect e... The issue of carbon emissions has been on the corporate sustainability agenda for some years. For those working in agricultural supply chains, the challenges remain significant, given the diverse direct and indirect emissions occurring throughout the value chain. This study determines the carbon footprint of the supply chain of Costa Rican coffee exported to Europe, using best practice methodology to calculate greenhouse gas emissions. Overall, it was found that the total carbon footprint across the entire supply chain is 4.82 kg CO2e kgx green coffee. The carbon footprint of the processes in Costa Rica to produce l km of green coffee is 1.77 kg CO2e. The processes within Europe generate 3.05 kg CO2e kg-1 green coffee. This carbon footprint is considered as "very high intensity". This paper also identifies the sources of the most intense emission and discusses mitigation possibilities on which efforts must be focused. 展开更多
关键词 Climate change carbon footprint coffee supply chain Costa rica.
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Greenhouses Gases, Carbonyls, and Volatile Organic Compounds Surface Flux Emissions at Three Final Waste Disposal Sites Located in the Metropolitan Area of Costa Rica
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作者 Jorge Herrera Murillo José Félix Rojas Marín +1 位作者 Víctor Hugo Beita Guerrero José Chinchilla Salazar 《Open Journal of Air Pollution》 2017年第4期149-164,共16页
The surface flux emissions for volatile organic compounds (VOC’s) (alcohols and aromatic species), priority carbonyls and greenhouse gases, were measured in three different final disposal sites for urban solid waste ... The surface flux emissions for volatile organic compounds (VOC’s) (alcohols and aromatic species), priority carbonyls and greenhouse gases, were measured in three different final disposal sites for urban solid waste located in the metropolitan area of Costa Rica, between July and October 2014. The emissions fluxes were determined using the static sampling chamber technique coupled to two different adsorption tubes: active charcoal (Supelco, ORBO 32) to capture BTEX and alcohols;and 2,4-DNPH coated silica gel (SKC, 226-119) for carbonyls. As for the VOCs, the BTEX, Alcohols, and Carbonyls total fluxes were in the range of 3 to 258, 1 to 318 and 0.4 to 8.5 mg/(m2d&#237a), respectively. The magnitudes per site were in the following order La Carpio > El Huaso > Rio Azul. Ethanol and BTEX presented a high correlation in all the cases because possibly they are sharing the same sources or formation mechanisms. The emission fluxes spatial distributions among the sites were very variable and dependent on the location of the active cells and their age. Only La Carpio showed a more homogeneous distribution due to its middle age. 展开更多
关键词 GHG Volatile Organic Compounds Costa rica LANDFILLS Surface Emission FLUXES
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National Inventory of Mercury Release into Different Environmental Sectors Estimated by United Nations Environment Programme (UNEP) Toolkit in Costa Rica
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作者 Aguilar Maria Mora Jose +2 位作者 Sibaja Jose Valdés Juan Zabala Walter 《Open Journal of Air Pollution》 2017年第2期76-92,共17页
This paper summarizes the national inventory of mercury released into all environmental sectors (air, water, land, impurity in products, general wastes and sector specific treatment/disposal) for the year 2008 in the ... This paper summarizes the national inventory of mercury released into all environmental sectors (air, water, land, impurity in products, general wastes and sector specific treatment/disposal) for the year 2008 in the country of Costa Rica, using the United Nations Environment Programme (UNEP) mercury toolkit. The data collection about the input and output of mercury for the year 2008, was carried out during the years 2014 and 2015. The data used for estimation are mainly obtained from the Costa Rican Government’s official publications. The research was developed in order to create a national inventory of mercury releases into all environmental sectors in order to aid mercury management in Costa Rica. Total input and output of mercury, distribution into different environmental sectors, major contributions by mercury sources (“steps” “categories” and “subcategories”) are discussed. The standard estimation of total mercury input is 7174.00 kg/year. The biggest mercury input are “waste treatment and recycling” (3086.00 kg Hg, 43.17%) and “general consumption of mercury in products, as metal mercury and as mercury containing substances” (3189.00 kg Hg, 44.62%). The total mercury released is 31,689.29 kg/year. The biggest emission of mercury corresponds to the source “waste treatment and recycling” (28,359.29 kg/year, 89.49%). The “air” is the main impacted environmental sector due the different mercury inputs. A total of 28,155.60 kg/year (88.55%) is released in this media. Only 1635.10 kg/year (5.16%) of the total mercury emissions is deposited in the environmental sector named “general waste”. The rest of the environmental sectors evaluated are impacted with less of 3.00% of the total mercury released. 展开更多
关键词 Costa rica MERCURY Enviromental SECTORS Air WASTES Input Output UNEP TOOLKIT
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Near Surface Carbon Dioxide and Methane in Urban Areas of Costa Rica
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作者 Germain Esquivel-Hernández Mario Villalobos-Forbes +3 位作者 Ricardo Sánchez-Murillo Christian Birkel Juan Valdés-González Jan Boll 《Open Journal of Air Pollution》 2015年第4期208-223,共16页
Little information is available for Central America regarding methane and carbon dioxide mixing ratios in urban areas. This work reports a representative spatial and seasonal study of near surface carbon dioxide and m... Little information is available for Central America regarding methane and carbon dioxide mixing ratios in urban areas. This work reports a representative spatial and seasonal study of near surface carbon dioxide and methane, carried out between July 2014 and January 2015 (27 weeks) in the Central Valley of Costa Rica, and other urban and rural sites across the country and covering three distinct seasons: Mid-summer drought (July-August), wet season (September-November) and transition period (December-January). The mixing ratios of both gases are clearly influenced by the metropolitan area, and by the prevailing atmospheric conditions during the wet season months. Average carbon dioxide concentration (629 ± 80 ppm) and average methane concentration (2192 ± 110 ppb) were up to 8% and up to 10%, respectively, higher during the wet season than the values recorded outside this period. HYSPLIT back air mass trajectories analysis, and weather data available for the Central Valley, suggest that these differences arise as result of a reduction in the mixing layer of depth (~425 m) and the wind speed (~1.5 m/s) across the valley, favoring the accumulation of polluted air masses in the metropolitan area. Other natural and anthropogenic sources, like the volcanic emissions of the Turrialba Volcano and the livestock activities at rural sites, apparently influence the mixing ratios of both gases across Costa Rica. Although the scope of this study is limited to representative seasonal conditions of the Central Valley in 2014 and 2015, it is possible considering the information presented in this work that the “dome” phenomenon can be assumed to exist. 展开更多
关键词 CARBON Dioxide METHANE URBAN Areas Costa rica HYSPLIT ATMOSPHERIC Conditions
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Source Apportionment of PM2.5 in the Metropolitan Area of Costa Rica Using Receptor Models
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作者 Jorge Herrera Murillo Susana Rodríguez Roman +1 位作者 José Félix Rojas Marín Beatriz Cardenas 《Atmospheric and Climate Sciences》 2013年第4期562-575,共14页
In this work, receptor models were used to identify the PM2.5 sources and its contribution to the air quality in residential, comercial and industrial sampling sites in the Metropolitan Area of Costa Rica. Principal c... In this work, receptor models were used to identify the PM2.5 sources and its contribution to the air quality in residential, comercial and industrial sampling sites in the Metropolitan Area of Costa Rica. Principal component analysis with absolute principal component scores (PCA-APCS), UNIMX and positive matrix factorization (PMF) was applied to analyze the data collected during 1 year of sampling campaign (2010-2011). The PM2.5 samples were characterized through its composition looking for trace elements, inorganic ions and organic and elemental carbon. These three models identified some common sources of PM2.5: marine aerosol, crustal material, traffic, secondary aerosols (secondary sulfate and secondary nitrate resolved by PMF), a mixed source of heavy fuels combustion and biomass burning, and industrial emissions. The three models predicted that the major sources of PM2.5 in the Metropolitan Area of Costa Rica were related to anthropogenic sources (73%, 65% and 69%, respectively, for PCA-APCS, Unmix and PMF) although natural sources also contributed to PM2.5 (21%, 24% and 26%). On average, PCA and PMF methods resolved 94% and 95% of the PM2.5 mass concentrations, respectively. The results were comparable to the estimate using UNMIX. 展开更多
关键词 PM2.5 Chemical COMPOSITION Costa rica SOURCE APPORTIONMENT RECEPTOR Models
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Analysis of Benzene Exposure Levels on Commuters Traveling within the Metropolitan Area of Costa Rica
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作者 Wendy Villalobos-Gonzalez Germain Esquivel-Hernandez +2 位作者 Ricardo Sanchez-Murillo José Leonardo Corrales-Salazar Juan Valdes-Gonzalez 《Open Journal of Air Pollution》 2015年第1期38-46,共9页
This study reports the benzene exposure levels of commuters traveling within the metropolitan area of Costa Rica using personal cars, buses, and urban trains. 47 in-vehicle samples were collected in the 2014 wet seaso... This study reports the benzene exposure levels of commuters traveling within the metropolitan area of Costa Rica using personal cars, buses, and urban trains. 47 in-vehicle samples were collected in the 2014 wet season under three different driving conditions: rush hour traffic, normal traffic and weekends. Samples were collected in Tedlar bags and analyzed using 75 μm carboxenpolydimethylsiloxane (CAR/PDMS) and gas chromatography with flame ionization detection (GC-FID). Additionally, duplicate samples were collected on adsorption tubes filled with Tenax TA and analyzed by thermal desorption (TD) and GC-FID. Results indicate that travelling in cars and buses under rush hour conditions exposes commuters to statistically equal average benzene concentration of 48.7 and 51.6 μg/m3, respectively. Average benzene levels in urban trains (33.0 μg/m3) were measured only during morning rush hours. Greater benzene levels in buses than personal cars concentrations may be attributable to the immersion of traffic-related emission within the bus cabins. Factors, such as the driving pattern, the number of vehicles on the route, the road infrastructure, and the prevalence of gasoline-fueled vehicles in Costa Rica, may increase ambient benzene concentrations. Benzene levels inside car cabins reported in this study are in the range of those reported in other urban areas;however, the corresponding concentrations inside buses and urban trains (rush hour only) are higher than previously published exposure levels. 展开更多
关键词 Costa rica Benzene EXPOSURE LEVELS Solid Phase MICROEXTRACTION (SPME) Traffic Hours COMMUTERS EXPOSURE
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Farmers' Perceived Impact of Fair Trade: The Case of Costa Rica
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作者 C. Zanasi C. Rota S. Bontempi G. Panini M. Setti 《Journal of Environmental Science and Engineering》 2010年第10期78-84,共7页
The perceived usefulness of Fair Trade influences both its effectiveness and farmers' long-term participation. The aim of this paper is to measure the perceived economic, social and environmental impact of Fair Trade... The perceived usefulness of Fair Trade influences both its effectiveness and farmers' long-term participation. The aim of this paper is to measure the perceived economic, social and environmental impact of Fair Trade by farmers in Costa Rica. One hundred farmers were interviewed, and their perceived change in living and working conditions due to Fair Trade participation was measured through a t-test analysis. The sample characters' influence on the perceived change was also measured, adopting a regression model and a t-test. The results showed a positive perception of the impact of Fair Trade, with a particularly strong perceived improvement in the farmers' technical, economic and managerial skills. There was relatively less perceived change in the environmental, educational and sanitary conditions. The results showed the need for Fair Trade to better adjust its strategy to the expectations of the farmers' communities. 展开更多
关键词 Fair Trade IMPACT Costa rica technology acceptance model small farmers
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基于RICA的高光谱遥感影像地物识别研究
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作者 陈昀琳 《无线互联科技》 2022年第17期137-139,共3页
高光谱影像具有光谱分辨率高、光谱覆盖范围更宽且波段多等优点,但其数据量巨大导致数据存在大量冗余、图像数据预处理困难,极大地限制了高光谱影像的应用。文章在ICA算法的基础上,以软重建惩罚替换ICA的正交性约束来克服ICA的缺点,实... 高光谱影像具有光谱分辨率高、光谱覆盖范围更宽且波段多等优点,但其数据量巨大导致数据存在大量冗余、图像数据预处理困难,极大地限制了高光谱影像的应用。文章在ICA算法的基础上,以软重建惩罚替换ICA的正交性约束来克服ICA的缺点,实现基于RICA的高光谱降维算法。本研究对高分5号遥感影像进行PCA、ICA和RICA降维实验,应用支持向量机进行分类。实验结果表明,RICA算法在高光谱降维中是更加有效的。 展开更多
关键词 高光谱图像 降维 rica 支持向量机
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