12 research outputs found

    A study on the effects of volcanic ash on the growth and mortality of Tilapia nilotica fingerling and junevile

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    Tilapia nilotica fingerlings and juveniles were exposed to high (2-3 g/L), median (1.2-4, g/L) and low (0.4-0.6 g/L) concentrations of volcanic ash for a period of 90 days of three months. Such exposure did not cause mortality but instead, helped in the promotion of algae (an alternative feed), leading to differences in feeding habits between the control and the treatment group (the control consumed less feeds). After the experiment, the tissues of the different organs (gills, liver and intestine) of the control as well as the treatment group were observed. It was reported that there is no detectable abnormalities between the sample of the control and the treatment group

    Environmental and Socioeconomic Impacts of Shrimp Farming in the Philippines: A Critical Analysis Using PRISMA

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    Shrimp aquaculture is under pressure to increase its production to meet the growing demand for food from a growing population. In the Philippines, aquaculture has experienced the shift from milkfish to prawn, with its attractive marketable price. This intensification has led to negative and positive impacts, which have raised a range of environmental and socioeconomic problems. This paper reviews the environmental and socioeconomic challenges that the shrimp aquaculture industry faces using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. We examine the gaps and the changes that are required to revitalize the industry. We examine and assess the impacts of shrimp culture on the environment, e.g., shrimp farm management, marine pollution, disease outbreaks, and the social, economic, and climate change impacts. The presence of viral diseases, such as White Spot Syndrome Virus (WSSV), Monodon Baculovirus (MBV), Infectious Hypodermal and Hematopoietic Necrosis Virus (IHHNV), Hepatopancreatic Parvovirus (HPV), and Yellow Head Virus (YHV), have caused approximate losses in the industry of 40,080 mt in 1997, and 51,000 mt in 2014. Recommended strategies and policy changes are considered for the improvement of shrimp aquaculture, including disease management, the adoption of good aquaculture practices, proper environmental monitoring, sustainable practices at the farm level, and priorities for cooperation among the concerned government agencies and local governments, as well as the involvement of state universities and colleges, for better management practices

    Sustainable Feedstocks and Challenges in Biodiesel Production: An Advanced Bibliometric Analysis

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    Biodiesel can be produced from vegetable oils, animal fats, frying oils, and from microorganism-synthesized oils. These sources render biodiesel an easily biodegradable fuel. The aim of this work was to perform an advanced bibliometric analysis of primary studies relating to biodiesel production worldwide by identifying the key countries and regions that have shown a strong engagement in this area, and by understanding the dynamics of their collaboration and research outputs. Additionally, an assessment of the main primary feedstocks employed in this research was carried out, along with an analysis of the current and future trends that are expected to define new paths and methodologies to be used in the manufacture of biodegradable and renewable fuels. A total of 4586 academic outputs were selected, including peer-reviewed research articles, conference papers, and literature reviews related to biodiesel production, in the time period spanning from 2010 to 2021. Articles that focused on feedstocks for the production of biodiesel were also included, with a search that returned 330 papers. Lastly, 60 articles relating to biodiesel production via sewage were specifically included to allow for an analysis of this source as a promising feedstock in the future of the biofuel market. Via the geocoding and the document analyses performed, we concluded that China, Malaysia, and India are the largest writers of articles in this area, revealing a great interest in biofuels in Asia. Additionally, it was noted that environmental concerns have caused authors to conduct research on feedstocks that can address the sustainability challenges in the production of biodiesel

    Monitoramento atmosférico passivo de SO2, NO2 e O3 em áreas urbanas e de influência industrial como prática de química ambiental para alunos de graduação Atmospheric passive monitoring of SO2, NO2 and O3 in urban areas and in those under industrial influence as an environmental chemistry experiment for undergraduate students

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    <abstract language="eng">This study is a result of undergraduate student participation in the Environmental Chemistry discipline provided by the Chemistry Institute/UFBA. The students were involved in the development of passive samplers, a project of the LAQUAM (Environmental Analytical Chemistry Laboratory). The students' residences and other neighborhoods were used to create a passive sampling network, allowing the measurement of atmospheric levels of pollutants in urban areas and in those under industrial influence. The assembly of the passive samplers, including impregnation of filters and chemical analysis were part of the students' practice tasks. The results were analyzed taking into consideration the Brazilian legislation

    A Comprehensive Review on the Use of Metal–Organic Frameworks (MOFs) Coupled with Enzymes as Biosensors

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    Several studies have shown the development of electrochemical biosensors based on enzymes immobilized in metal–organic frameworks (MOFs). Although enzymes have unique properties, such as efficiency, selectivity, and environmental sustainability, when immobilized, these properties are improved, presenting significant potential for several biotechnological applications. Using MOFs as matrices for enzyme immobilization has been considered a promising strategy due to their many advantages compared to other supporting materials, such as larger surface areas, higher porosity rates, and better stability. Biosensors are analytical tools that use a bioactive element and a transducer for the detection/quantification of biochemical substances in the most varied applications and areas, in particular, food, agriculture, pharmaceutical, and medical. This review will present novel insights on the construction of biosensors with materials based on MOFs. Herein, we have been highlighted the use of MOF for biosensing for biomedical, food safety, and environmental monitoring areas. Additionally, different methods by which immobilizations are performed in MOFs and their main advantages and disadvantages are presented

    A Comprehensive Review on the Use of Metal&ndash;Organic Frameworks (MOFs) Coupled with Enzymes as Biosensors

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    Several studies have shown the development of electrochemical biosensors based on enzymes immobilized in metal&ndash;organic frameworks (MOFs). Although enzymes have unique properties, such as efficiency, selectivity, and environmental sustainability, when immobilized, these properties are improved, presenting significant potential for several biotechnological applications. Using MOFs as matrices for enzyme immobilization has been considered a promising strategy due to their many advantages compared to other supporting materials, such as larger surface areas, higher porosity rates, and better stability. Biosensors are analytical tools that use a bioactive element and a transducer for the detection/quantification of biochemical substances in the most varied applications and areas, in particular, food, agriculture, pharmaceutical, and medical. This review will present novel insights on the construction of biosensors with materials based on MOFs. Herein, we have been highlighted the use of MOF for biosensing for biomedical, food safety, and environmental monitoring areas. Additionally, different methods by which immobilizations are performed in MOFs and their main advantages and disadvantages are presented

    Modesty and modernity: photography, race, and representation on Mexico’s Costa Chica (Guerrero)

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    This article uses ethnographic techniques to examine photographic practices in and around San Nicolás Tolentino, Guerrero, a rural community in a historically black region of Mexico. At its core is a juxtaposed interpretation of a book of photographs entitled Tierra Negra (Black Earth), taken by a Mexican photographer in the early 1990s, and local people’s “home” photos, mostly portraits of family members displayed on the walls of sitting rooms. In 2001, I brought Tierra Negra to San Nicolás in order to elicit local people’s responses to the photographs, which turn out to be mostly of them. Through their comments on these photos, as well as discourses around their home photos, I elaborate on identity issues and local people’s formulations of progress and modernity. I situate my analysis in the historical and anthropological scholarship on race and photographic representation as I draw conclusions about the distinct yet overlapping meanings that “outsiders” and “insiders” give to blackness and the values that such blackness holds as commodity, as historical memory and as one of the roots of Mexican national identity

    The large aperture gamma ray observatory as an observational alternative at high altitude

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    To appear in Conference Title (2007). Rev Mex AA(SC)A pesar de que las observaciones por satélite han permitido desvelar algunos misterios sobre el origen y localización de rayos cósmicos a bajas energías, hay preguntas aún no resueltas en los rangos mas altos de energías (> 1 GeV). El ujo de partículas a altas energías es muy bajo, necesitando de grandes áreas de medición, por lo que la detección de partículas secundarias en observatorios sobre la super cie terrestre representa una solución viable. Aunque el Observatorio Pierre Auger tiene esa capacidad, dados sus 16:000m2 de detectores, su baja altura sobre el nivel del mar reduce en gran medida su capacidad de detección. El proyecto LAGO es una alternativa de observación aceptable, que intenta superar ésta limitación. Este proyecto iniciado en el 2005, sitúa detectores Cherenkov de agua a gran altura. Los sitios de observaci on han sido seleccionados siguiendo algunos requisitos básicos, a saber: altitud, infraestructura académica y técnica, existencia de un grupo de investigación responsable del montaje y mantenimiento de los detectores así como de la visualización, análisis, divulgación y preservación de los datos. Este artículo presenta el estado general de los observatorios de Sierra Negra-México, Chacaltaya-Bolívia, Marcapomacocha-Perú, Mérida-Venezuela y [email protected] satellite observations have revelaedsome mysteries about the origin and location of cosmic rays at low energies, questions remain to be resolved in higher energy ranges (> 1 GeV). However, the ow of particles at high energies is very low, large sensitive areas are necessary, so that the detection of secondary particles from observatories on the surface of the earth is a technically viable solution. While the Pierre Auger Observatory has such capacity given its 16000 m2 of detectors, low height above sea level greatly reduces its detection capability. The Large Aperture Gamma Ray Observatory (LAGO) is an observational alternative that attempts to overcome this limitation. This project was started in 2005, placing water Cherenkov Detectors at high altitude. Observation sites have been selected with some basic requirements: altitude, academic and technical infrastructure, existence of a research group responsible for assembly and maintenance of the detectors and the analysis, visualization, divulgation and data storage. This paper presents the general status of the observatories of Sierra Negra-México, Chacaltaya-Bolívia, Marcapomacocha-Perú, Mérida-Venezuela and Bucaramanga-Colombi
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