• Title/Summary/Keyword: Americas

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Petrochemical effluent treatment using natural coagulants and an aerobic biofilter

  • Bandala, Erick R.;Tiro, Juan Bernardo;Lujan, Mariana;Camargo, Francisco J.;Sanchez-Salas, Jose Luis;Reyna, Silvia;Moeller, Gabriela;Torres, Luis G.
    • Advances in environmental research
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    • v.2 no.3
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    • pp.229-243
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    • 2013
  • Coagulation-flocculation (CF) was tested coupled with an aerobic biofilter to reduce total petroleum hydrocarbon (TPHs) concentration and toxicity from petrochemical wastewater. The efficiency of the process was followed using turbidity and chemical oxygen demand (COD). The biofilter was packed with a basaltic waste (tezontle) and inoculated with a bacterial consortium. Toxicity test were carried out using Lactuca sativa var. capitata seeds. Best results for turbidity removal were obtained using alum. Considerable turbidity removal was obtained when using Opuntia spp. COD removal with alum was 25%, for Opuntia powder it was 36%. The application of the biofilter allowed the removal of 70% of the remaining TPHs after 30 days with a biodegradation rate (BDR) value 47 $mgL^{-1}d^{-1}$. COD removal was slightly higher with BDR value 63 $mgL^{-1}d^{-1}$. TPH kinetics allowed a degradation rate constant equal to $4.05{\times}10^{-2}d^{-1}$. COD removal showed similar trend with $k=4.23{\times}10^{-2}d^{-1}$. Toxicity reduction was also successfully achieved by the combined treatment process.

Current status, challenges and prospects for dairy goat production in the Americas

  • Lu, Christopher D.;Miller, Beth A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.8_spc
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    • pp.1244-1255
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    • 2019
  • Dairy goat production continues to be a socially, economically and culturally important part of the livestock industry in North, Central and South America and the Caribbean islands. Goat milk, cheese and other dairy products offer consumers food products with nutritional, health and environmental benefits. In North America, Mexico produces the greatest volume of goat milk, but most is for family or local consumption that is typical of a mixed farming system adopted by subsistence farmers in dry areas. The United States is not yet a large global goat milk producer, but the sector has expanded rapidly, with dairy goat numbers doubling between 1997 and 2012. The number of dairy goats has also increased dramatically in Canada. Commercial farms are increasingly important, driven by rising demand for good quality and locally sourced goat cheese. In South America, Brazil has the most developed dairy goat industry that includes government assistance to small-scale producers and low-income households. As of 2017, FAO identified Haiti, Peru, Jamaica, and Bolivia as having important goat milk production in the Western Hemisphere. For subsistence goat producers in the Americas on marginal land without prior history of chemical usage, organic dairy goat production can be a viable alternative for income generation, with sufficient transportation, sanitation and marketing initiatives. Production efficiency, greenhouse gas emission, waste disposal, and animal welfare are important challenges for dairy goat producers in the Americas.

Temporal and Spatial Distribution of Enterobius vermicularis (Nematoda: Oxyuridae) in the Prehistoric Americas

  • Reinhard, Karl J.;Araujo, Adauto;Morrow, Johnica J.
    • Parasites, Hosts and Diseases
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    • v.54 no.5
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    • pp.591-603
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    • 2016
  • Investigations of Enterobius sp. infection in prehistory have produced a body of data that can be used to evaluate the geographic distribution of infection through time in the Americas. Regional variations in prevalence are evident. In North America, 119 pinworm positive samples were found in 1,112 samples from 28 sites with a prevalence of 10.7%. Almost all of the positive samples came from agricultural sites. From Brazil, 0 pinworm positive samples were found in 325 samples from 7 sites. For the Andes region, 22 pinworm positive samples were found in 411 samples from 26 sites for a prevalence of 5.3%. Detailed analyses of these data defined several trends. First, preagricultural sites less frequently show evidence of infection compared to agricultural populations. This is especially clear in the data from North America, but is also evident in the data from South America. Second, there is an apparent relationship between the commonality of pinworms in coprolites and the manner of constructing villages. These analyses show that ancient parasitism has substantial value in documenting the range of human behaviors that influence parasitic infections.

Response transformation factors for deterministic-based and reliability-based seismic design

  • Bojorquez, Eden;Bojorquez, Juan;Ruiz, Sonia E.;Reyes-Salazar, Alfredo;Velazquez-Dimas, Juan
    • Structural Engineering and Mechanics
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    • v.46 no.6
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    • pp.755-773
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    • 2013
  • One of the main requirements of the seismic design codes must be its easy application by structural engineers. The use of practically-applicable models or simplified models as single-degree-of-freedom (SDOF) systems is a good alternative to achieve this condition. In this study, deterministic and probabilistic response transformation factors are obtained to evaluate the response in terms of maximum ductility and maximum interstory drifts of multi-degree-of-freedom (MDOF) systems based on the response of equivalent SDOF systems. For this aim, five steel frames designed with the Mexican City Building Code (MCBC) as well as their corresponding equivalent SDOF systems (which represent the characteristics of the frames) are analyzed. Both structural systems are subjected to ground motions records. For the MDOF and the simplified systems, incremental dynamic analyses IDAs are developed in first place, then, structural demand hazard curves are obtained. The ratio between the IDAs curves corresponding to the MDOF systems and the curves corresponding to the simplified models are used to obtain deterministic response transformation factors. On the other hand, demand hazard curves are used to calculate probabilistic response transformation factors. It was found that both approaches give place to similar results.

Assessment of infection control in oral radiology during the COVID-19 outbreak: An international collaborative study

  • Rafaela C Santos;Larissa S Araujo;Rafael B Junqueira;Eliana D Costa;Fernanda M Pigatti;Kivanc Kamburoglu;Pedro HB Carvalho;Manuela LB Oliveira;Sibele N Aquino;Francielle S Verner
    • Imaging Science in Dentistry
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    • v.53 no.4
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    • pp.365-373
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    • 2023
  • Purpose: In the context of COVID-19, studies evaluating the adherence of dentists and dental students to infection control are relevant due to their high occupational exposure and risk, as well as their responsibility for disseminating information and good practices. This study evaluated the adherence of dentists and dental students to infection control in the oral radiology field in the setting of the COVID-19 pandemic on different continents. Materials and Methods: This cross-sectional observational study involved individuals who performed intraoral radiographic examinations during the COVID-19 pandemic. The Questionnaire on Infection Control in Oral Radiology was administered virtually using a Google Form. Participants from different continents(the Americas, Africa, Europe, Asia, and Oceania) were recruited. Data were subjected to descriptive analysis and simple and multiple binary regression (5%). Results: There were 582 valid answers, and 68.73% of the participants were from the Americas, 18.90% from Europe, and 12.37% from Asia. The median score for infection control protocols was 94 points for dental students and 104 points for dentists, and participants below the median were considered to have low adherence to infection control in oral radiology. Low access to infection control was found for 53.0% of dentists in the Americas, 34.0% from Europe, and 26.9% from Asia. Conclusion: The adherence to infection control protocols in oral radiology was low even in the face of the COVID-19 pandemic. The results may help improve the awareness of students and professionals, since oral radiology routines have the potential for transmitting COVID-19.

CONNECTING EURASIA AND THE AMERICAS: EXTENSION OF THE HISTORICAL SILK ROAD AND ITS GEOPOLITICAL IMPLICATIONS

  • ERDEM, CAGRI
    • Acta Via Serica
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    • v.2 no.2
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    • pp.133-162
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    • 2017
  • The Bering Strait crossing would link the entirety of Eurasia to the entirety of the Americas, and it can be seen as a natural extension of the historical Silk Road. There are some immense geopolitical benefits to such a project. It would bring about a profound and lasting change to the global economic and political outlook. The most valued function of the Bering Strait crossing and the extension of the associated railroad network would be to release the massive natural resources trapped underneath the tundra and permafrost for the benefit of Russia and the world. Moreover, the railroad project(s) would also build development corridors in those underdeveloped parts of the Russian Federation. The development of the resources and their rapid transportation to the global markets would contribute not only to the overall development of the region but also would be valuable for the resource-poor countries of Northeast Asia such as Japan, Korea, and China (relative to its economic size). This paper will explore the possible impact(s) of the Bering Strait crossing as a formidable infrastructure project for the economic development of the Russian Far East (RFE) from the Russian perspective under the frame of geopolitics. Furthermore, it will equally scrutinize the implications for the adjacent countries in the region.

The Impact of Korean Wave Cultural Contents on the Purchase of Han-Sik (Korean food) and Korean Product - Based on the Survey of Asia (Japan, China), Americas and Europe - (한류 문화콘텐츠가 한식 및 한국 제품 구매에 미치는 영향 - 아시아 (중국, 일본), 미주, 유럽지역을 중심으로 -)

  • Shin, Bong-Kyu;Oh, Mi-Hyun;Shin, Tack-Su;Kim, Yoon-Sun;You, Sang-Mi;Roh, Gi-Youp;Jung, Kyoung-Wan
    • Journal of the Korean Society of Food Culture
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    • v.29 no.3
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    • pp.250-258
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    • 2014
  • This research investigated the relationship among Korean Wave Cultural Contents consumption of Korean food, Korean products, and Learning of the Korean language. The survey targeted non-Koreans who were either interested in or experienced Korean Wave Cultural Contents. Exactly 61.3% of subjects had traveled to Korea. The most common method of experiencing the Korean Wave was via the Internet (57.7%), followed by TV (21.1%) and Mobile (7.7%). The most popular Korean Wave Contents were K-pop (35.2%) and TV Dramas (31.0%). Movies were preferred in the Americas ($3.63{\pm}0.83$) and Asia ($3.63{\pm}1.09$), whereas K-pop was preferred in Asia ($3.68{\pm}1.12$) and games preferred in Europe ($2.50{\pm}1.56$). Regarding Korean food, most participants had tasted Kimchi (81.7%), followed by Bulgogi (74.6%), Bibimbap (66.9%), and Galbi (66.2%). According to the country-by-country survey, in the case of Galbi (p<0.05), Bibimbap (p<0.05), and Bulgogi (p<0.05), Asians had more experiences with Korean food compared to those from other regions. Meanwhile, in the case of satisfaction of Korean food, Bulgogi ($4.22{\pm}1.05$) was ranked highest, whereas Kimchi ($3.85{\pm}1.15$) was ranked lowest. According to the region-by-region survey, those from Oceania and other regions preferred Kimchi ($4.25{\pm}0.71$) and Bulgogi ($4.50{\pm}4.50$) while the Americas preferred Galbi ($4.82{\pm}0.39$) and Bibimbap ($4.54{\pm}0.81$). Bulgogi ($2.76{\pm}0.06$) was highly ranked as a representative Korean Food while Kimchi ($2.44{\pm}0.71$) was ranked the lowest. This research explained that among Korean Wave Cultural Contents, movies and music positively influenced on the 'Image of Korea', movies and K-pop effected 'Purchasing intention of Korean products', and TV Dramas, movies, and K-pop effected 'Purchasing intention of Korean Food'.