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Arquitectura radical y estados fenológicos de cultivos andinos quínoa, amaranto, lupino y alforfón en un Andisol del sur de Chile
Get PDFEn Andisoles del sur de Chile, el rendimiento de los cultivos está principalmente limitado por fijación de fósforo (P) y fitotoxicidad por aluminio (Al3+), existieron escasos antecedentes sobre rotaciones con trigo que incluyan cultivos andinos. Resulta relevante el conocimiento de la arquitectura radical en estos cultivos con el fin de mejorar su productividad, al otorgar una mayor capacidad de absorción de agua, nutrientes y tolerancia a estreses bióticos y abióticos. El objetivo del trabajo fue evaluar la arquitectura
radical en estadios tempranos de desarrollo de cultivos andinos establecidos en un Andisol del sur de Chile en condiciones de campo. Durante la temporada 2019/2020 se estableció un ensayo en campo utilizando cuatro cultivos: alforfón (Fagopyrum esculentum L.), amaranto (Amaranthus spp.), lupino (Lupinus albus L.) y quínoa (Chenopodium quinoa L.), todos no micorrizables, y como comparación se usó avena (Avena sativa L.), un cultivo micorrizable. En el periodo de crecimiento se realizaron cuatro
muestreos de plantas y suelo registrando estadios fenológicos y evaluando arquitectura de raíces, pH del suelo y P disponible. En la primera mitad del ciclo vegetativo, el crecimiento de los cultivos fue continuo y se redujo drásticamente al final del ciclo de desarrollo, por la sequía imperante durante los meses de verano. Estas condiciones climáticas afectaron a quínoa y lupino, los cuales mostraron alta sensibilidad al estrés hídrico. En general, en todos los cultivos se observó una buena arquitectura radical, lo que sugiere una movilización de P en forma más eficiente. Mayor longitud radical se obtuvo en el alforfón, mientras que mejor capacidad de adaptación al medio se observó en quínoa. Se concluye que, mediante un adecuado manejo agronómico al incorporar quínoa o amaranto como precultivos en rotación con trigo, se podría incrementar la disponibilidad de P para el cultivo siguiente reduciendo la aplicación de fertilizantes químicos.In Andisols of Southern Chile, crop yield is mainly limited by P fixation and aluminum phytotoxicity (Al 3+ ), but scarce information in these soils is known in rotations, including wheat after Andean crops. It is very relevant to the knowledge of such crops'root architecture to improve productivity through a greater absorption capacity of water, nutrients, and tolerance to biotic and abiotic stresses. The objective of this work was to evaluate root architecture at early phenological stages of Andean crops in an acidic Andisol from Southern Chile. During the 2019/2020 season, a field trial was established using four non-mycorrhizal cultures: buckwheat (Fagopyrum esculentum L.), amaranth (Amaranthus spp.), lupine (Lupinus albus L.), and quinoa (Chenopodium quinoa L.), and compared with oats (Avena sativa L.) a mycorrhizal culture. During the growth period, four plant and soil samplings were carried out, evaluating phenological stages, root architecture, together with soil pH and P-availability. During the first half of the vegetative cycle, the growth of the crops was continuous but drastically reduced at the end development cycle due to the prevailing drought during the summer months. These climatic conditions affected quinoa and lupine growth showing high sensitivity to water stress. In general, all crops showed good root architecture, suggesting a more efficient P mobilization. A greater root length was obtained in buckwheat, while a better adaptation capacity to the environmental conditions was observed in quinoa. It is concluded that through suitable agronomic management by incorporating quinoa or amaranth as pre-crops of wheat in a rotation, the P-availability for the next crop could be increased by reducing the application of chemical fertilizers
RECOGNITION OF IMMIGRANTS' FREEDOM OF TRANSIT IN CHILEAN SUPERIOR COURTS OF JUSTICE. STUDIES ON SANCTIONS OF EXPULSION
No full textFrom a critical perspective of elements that integrate immigrants' legal status in Chile, we analyze its legal foundation from the configuration of the rights and freedoms generated by the freedom of transit contained in article 19 No 7 a), of the Constitution. A study of the doctrinal constructions and the guarantees of a constitutional nature to protect this freedom is carried, allowing a diagnosis of the main decisions of the superior courts of justice which have had a shaping view of the legal status of immigrants, in disagreement with the decisions of the Immigration and Foreign Affairs Department
THE IMPORTANCE OF RESETTING THE SOCIOLEGAL CULTURE OF TECHNOLOGY TRANSFER IN CHILE
No full textThis article analyzes the theoretical bases for the harmonization and integration of socio-legal guidelines that must be considered for the promotion of an innovative culture and technology transfer in Chile. The methods used were doctrinal legal, content analysis and doctrinal theoretical study. The analysis showed that the basic principles that serve as normative statements for the regulation of technology transfer in Chile have not yet been determined, a situation that affects the transfer of knowledge and research from the public sector or publicly funded to the private sector in a more efficient, orderly and effective way, with the active participation of the researchers or creators of said technologies, where the introduction and commercialization is developed by the entrepreneurs of the items interested in its commercialization. Universities are a relevant subject in the technological development of the nation, however, the integration, harmonization, and collaboration for the promotion of the technological innovation process must be oriented towards a conjugation with the business sector. For this, the lines of research must be aligned with this purpose and support the incorporation into the national and international market. Also, an orderly management of the subjects that participate in said processes is necessary, as well as strengthening the development of the intellectual property rights that are generated and the national system of technological innovation, and unifying the regulation of mechanisms to minimize the distortion and legislative dispersion in the matter
Is dairy wastewater safe for production of edible microbial biomass: A case study of Saras dairy plant at Jaipur, India
Get PDFMismanagement of wastewater at large scale may lead to catastrophic environmental and health consequences. Microbial remediation of wastewater is one of the most effective low-cost solutions. There are also initiatives to use wastewater for production edible biomass as an alternative for protein diets. While many researches were gearedtowards maximum recovery of biomass and applications, less wasfocused on mutagenicity of dairy wastewater.Wastewater fromone of the largest dairy industries in Rajasthanwasevaluatedfor its suitabilityfor microbial biomass production and mutagenicity. Influent wastewater was collected from Saras dairy plant, Jaipur, for 7 consecutive days. Physiochemical propertiesof wastewater were examined, such as; temperature, pH, salinity, TSS, TDS, turbidity, conductivity, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon(TOC), and total Kjeldahl nitrogen(TKN).SOS chromotest and Salmonellafluctuation test (TA 98, TA 100 and TA 102) were carried out at differentconcentrationsof wastewater to assess mutagenic activity.Results indicated ideal pH, temperature and salinity, for microbial remediation. High TOC and TKN were also observed in theinvestigated wastewater,which arefew of the prerequisites for single cell production. The ratio of BOD and COD was between 0.3-0.4, making the wastewater ideal for microbial growth. No mutagenic activity was observed by SOS chromotest, all three concentrations(C 0.01, C 0.1, and C 0.2)investigated were <1.5 IF. Likewise,mutagenic ratio for all three types of Salmonella revertants were below 1.2 threshold, for investigated concentrations (C 0.5, C 1, and C 10) of wastewater. Conclusively, examined influent wastewater is less likely to induce mutagenic activity at the investigated concentration. Through physiochemical analysis, the investigated wastewater assumed to be candidate substrate for microbial biomass production.La mala gestión de las aguas residuales a gran escala puede tener consecuencias catastróficas para la salud y el medio ambiente. La remediación microbiana de aguas residuales es una de las soluciones de bajo costo más efectivas. También existen iniciativas para utilizar aguas residuales para la producción de biomasa comestible como alternativa a las dietas proteicas. Si bien muchas investigaciones se orientaron hacia la máxima recuperación de biomasa y aplicaciones, menos se centró en la mutagenicidad de las aguas residuales de productos lácteos. Las aguas residuales de una de las industrias lácteas más grandes de Rajasthan se evaluaron para determinar su idoneidad para la producción de biomasa microbiana y su mutagenicidad. Las aguas residuales se recogieron de la planta lechera de Saras, Jaipur, durante 7 días consecutivos. Se examinaron las propiedades fisicoquímicas de las aguas residuales, tales como; temperatura, pH, salinidad, TSS, TDS, turbidez, conductividad, demanda bioquímica de oxígeno (DBO), demanda química de oxígeno (DQO), carbono orgánico total (COT) y nitrógeno Kjeldahl total (NKT). La cromotest SOS y la prueba de fluctuación de Salmonella (TA 98, TA 100 y TA 102) se llevaron a cabo a diferentes concentraciones de aguas residuales para evaluar la actividad mutagénica. Los resultados indicaron pH, temperatura y salinidad ideales para la remediación microbiana. También se observaron altos niveles de COTy NKTen las aguas residuales investigadas, que son algunos de los requisitos previos para la producción de células individuales. La proporción de DBO y DQO estaba entre 0.3-0.4, lo que hace que las aguas residuales sean ideales para el crecimiento microbiano. No se observó actividad mutagénica por cromotest SOS, las tres concentraciones (C 0.01, C 0.1 y C 0.2) investigadas fueron <1.5 IF. Asimismo, la proporción mutagénica para los tres tipos de revertientes de Salmonella estuvo por debajo del umbral de 1.2, para las concentraciones investigadas (C 0.5, C 1 y C 10) de aguas residuales. En conclusión, es menos probable que las aguas residuales influyentes examinadas induzcan actividad mutagénica a la concentración investigada. A través del análisis fisicoquímico, las aguas residuales investigadas se asumieron como sustrato candidato para la producción de biomasa microbiana
Evaluation of heavy metals in agricultural soils from Katsina State Nigeria
Get PDFThis work contributes to the monitoring of Agricultural soil pollution in Katsina State, North western Nigeria by assessing the degree of heavy metal pollution in Agricultural soil samples. Thestudy was conducted in the year 2017 within some catchment areas located within the 3 senatorial zones that constitute to make up the state (Katsina senatorial zone: Birchi, Dutsinma and Katsina; Daura senatorial zone: Daura, Ingawa and Zango; Funtua senatorial zone: Dabai, Funtua, Kafur, Malunfashi and Matazu). Analysis for the concentration of these heavy metals; Cr, Cd, Fe, Ni, Mn, Pb and Zn was conducted by the use of AAS (by Atomic Absorption Spectrophotometry) method. . Several indices were used to assess the metal contamination levels in the Agricultural soil samples, namely; Geo-accumulation Index (Igeo), Enrichment Factor (EF), Contamination Factor (CF), Degree of Contamination (Cd) and Pollution Load Index (PLI). The result of this study has shown that generally among the heavy metals evaluated, the highest concentration was observed for Fe (range: 20.195-38.347 ppm), followed by Zn (range: 0.528-1.134 ppm), Pb (range: 0.256-0.627 ppm), Mn (range: 0.261-0.572 ppm) and Cr (range: 0.093-0.344 ppm). While Cd has the lowest concentration (range: 0.022-0.043 ppm).For all the site sampled the heavy metal Ni was below detection level (BDL). From the results of heavy metals I-geo values, according to Muller’s classification, soil samples from Birchi, Daura, Dutsinma, Kafur and Zango were unpolluted (class 0) while soil samples from Dabai, Funtua, Ingawa, Katsina, Malunfashi and Matazu are moderately polluted (class 1). The result for the enrichment factor has shown that with the exception of the heavy metal Fe, which shows significant enrichment for all the sites sampled all the other heavy metals show deficiency to minimal enrichment. Also based on the contamination factors for all soil samples the heavy metal Fe has a CF values range of 1.2861-2.3240, indicating that the Agricultural soil samples are moderately contaminated with Fe. In contrast, the rest of the heavy metals exhibit low contamination in general. The value of PLI ranges from 0.2408 to 0.4935, indicating unpolluted to moderate pollution, with the sampling site for Katsina displaying the highest PLI valuewhile the sampling site of Ingawa has the lowest PLI. The Eri values for all samples are all < 40, presenting low ecological risk. The results suggest that the Agricultural soils samples from Katsina state has low contamination by the heavy metals evaluated.Este trabajo contribuye al monitoreo de la contaminación del suelo agrícola en el estado de Katsina, noroeste de Nigeria, mediante la evaluación del grado de contaminación por metales pesados en muestras de suelo agrícola. El estudio se realizóen el año 2017 dentro de algunas áreas de captación ubicadas dentro de las 3 zonas senatoriales que constituyen el estado (zona senatorial de Katsina: Birchi, Dutsinma y Katsina; zona senatorial de Daura: Daura, Ingawa y Zango; zona senatorial de Funtua: Dabai, Funtua, Kafur, Malunfashi y Matazu). Análisis para la concentración de estos metales pesados; Cr, Cd, Fe, Ni, Mn, Pb y Zn se llevaron a cabo mediante el uso del método AAS (por espectrofotometría de absorción atómica). . Se utilizaron varios índices para evaluar los niveles de contaminación de metales en las muestras de suelo agrícola, a saber; Índice de geoacumulación (Igeo), Factor de enriquecimiento (EF), Factor de contaminación (CF), Grado de contaminación (Cd) e Índice de carga de contaminación (PLI). Elresultado de este estudio ha demostrado que, generalmente, entre los metales pesados evaluados, se observóla concentración más alta para Fe (rango: 20.195-38.347 ppm), seguido de Zn (rango: 0.528-1.134 ppm), Pb (rango: 0.256-0.627 ppm), Mn (rango: 0.261-0.572 ppm) y Cr (rango: 0.093-0.344 ppm). Mientras que Cd tiene la concentración más baja (rango: 0.022-0.043 ppm). Para todo el sitio muestreado, el Ni de metales pesados estaba por debajo del nivel de detección (BDL). De los resultados de los valoresde I-geo de metales pesados, según la clasificación de Muller, las muestras de suelo de Birchi, Daura, Dutsinma, Kafur y Zango no estaban contaminadas (clase 0), mientras que las muestras de suelo de Dabai, Funtua, Ingawa, Katsina, Malunfashi y Matazu sonmoderadamente contaminado (clase 1). El resultado del factor de enriquecimiento ha demostrado que, con la excepción del Fe de metales pesados, que muestra un enriquecimiento significativo para todos los sitios muestreados, todos los demás metales pesados muestran una deficiencia de enriquecimiento mínimo. También basado en los factores de contaminación para todas las muestras de suelo, el Fe de metales pesados tiene un rango de valores de CF de 1.2861-2.3240, lo que indica que las muestras de suelo agrícola están moderadamente contaminadas con Fe. En contraste, el resto de los metales pesados exhiben baja contaminación en general. El valor de PLI varía de 0.2408 a 0.4935, lo que indica contaminación no contaminada a moderada, con el sitio de muestreo para Katsina mostrando el valor de PLI más alto, mientras que el sitio de muestreo de Ingawa tiene el PLI más bajo. Los valores de Eri para todas las muestras son <40, presentando bajo riesgo ecológico. Los resultados sugieren que las muestras de suelos agrícolas del estado de Katsina tienen baja contaminación por los metales pesados evaluados
Microalgae as Raw Materials for Aquafeeds: Growth Kinetics and Improvement Strategies of Polyunsaturated Fatty Acids Production
No full textStudies have shown that ancient cultures used microalgae as food for centuries. Currently, scientific reports highlight the value of nutritional composition of microalgae and their ability to accumulate polyunsaturated fatty acids at certain operational conditions. These characteristics are gaining increasing interest for the aquaculture industry which is searching for cost-effective replacements for fish meal and oil because these commodities are one of the most significant operational expenses and their dependency has become a bottleneck for their sustainable development of the aquaculture industry. This review is aimed at highlighting the use of microalgae as polyunsaturated fatty acid source in aquaculture feed formulations, despite their scarce production at industrial scale. Moreover, this document includes several approaches to improve microalgae production and to increase the content of polyunsaturated fatty acids with emphasis in the accumulation of DHA, EPA, and ARA. Furthermore, the document compiles several studies which prove microalgae-based aquafeeds for marine and freshwater species. Finally, the study explores the aspects that intervene in production kinetics and improvement strategies with possibilities for upscaling and facing main challenges of using microalgae in the commercial production of aquafeeds
A simulated marine heatwave impacts European sea bass sperm quantity, but not quality
No full textRapid environmental changes will be the major challenge that most biota will have to deal with in the near future. Extreme events, such as marine heatwaves, are becoming more frequent and could be spatially uniform at a regional scale for a relatively long period of time. To date, most research studies on heatwaves have focused on sessile organisms, but these extreme events can also impact mobile species. Here, a 3-week marine heatwave was simulated to investigate its effects on the male reproductive performance of a Mediterranean Sea emblematic species, the European sea bass Dicentrarchus labrax. Males from the control condition (c. 13 & DEG;C) produced significantly more sperm than those exposed to a relatively warm thermal treatment (c. 16 & DEG;C). Nonetheless, neither the percentage of motile spermatozoa nor most of the other sperm motility parameters were significantly affected by the rearing temperature over the whole period. Overall, the results of this study suggest only moderated effects of a potential winter heatwave on the reproductive performance of male European sea bass
Antioxidant activity and enzymatic of lichen substances: A study based on cyclic voltammetry and theoretical
No full textThe antioxidant activity of nine lichen substances, including methylatrarate (1), methyl haematommate (2), lobaric acid (3), fumarprotocetraric acid (4), sphaerophorin (5), subsphaeric acid (6), diffractaic acid (7), bar-batolic acid (8) and salazinic acid (9) has been determined through cyclic voltammetry. The compounds 1-4 presented slopes close to the Nernst constant of 0.059 V, indicating a 2H+/2e213; relation between protons and electrons, as long as the compounds 5, 6, 7, 8, and 9 present slopes between 0.037 V and 0.032 V, indicating a 1H+/2e/13; relation between protons and electrons. These results show a high free radical scavenging activity by means of the release of H+, suggesting an important antioxidant capacity of these molecules. Theoretical cal-culations of hydrogen bond dissociation enthalpies (BDE), proton affinities (PA), and Proton Transfer (PT) mechanisms, at M06-2x/6-311+G(d,p) level complement the experimental results. Computations support that the best antioxidant activity is obtained for the molecules (3, 4, 5, 6, 7 and 8), that have a carboxylic acid group close to a phenolic hydroxyl group, through hydrogen atomic transfer (HAT) and sequential proton loss electron transfer (SPLET) mechanisms. Additional computations were performed for modelling binding affinity of the lichen substances with CYPs enzymes, mainly CYP1A2, CYP51, and CYP2C9*2 isoforms, showing strong affinity for all the compounds described in this study
Nutrient and anti-nutrient composition of processed crayfish (Atya gabonensis) from river Benue, Nigeria
Get PDFThe species of crayfish identified as (Atya gabonensis) along River Benue Nigeria andwere captured and analyzed for nutrient and antinutrient content including, proximate composition (crude protein, crude fat, crude fiber, ash, and moisture content), as well as vitamin A, Vitamin B components, Vitamin C, Vitamin D, vitamin E, Vitamin K and select mineral concentrations. Additionally, some important antinutrients in crayfish were also examined. The proximate composition showed that moisture content was (9.54%), protein was (7.46%), Crude fibre was (5.60%), fat was (1.57%) and ash was (2.47%) respectively. This was found to be rich in protein and considerably high amount of moisture content. The anti-nutrient composition analysis revealed the presence of Saponin(0.471mg/100g), Alkaloid (3.905mg/100g), flavonoid (0.675mg/100g), tannin (0.017mg/100g), Phytate (0.060mg/100g), Oxalate (0.005mg/100g) and others, all of which are below toxic level. For mineral and vitamin compositions, potassium was significantly (P>0.05) higher than iron, zinc, magnesium, calcium and phosphorus while vitamin C was (4.920mg/100g) which is higher than all other vitamins evaluated. Based on these findings crayfish (Atya gabonensis) is recommended for consumption and for further investigation as a potential raw material for the pharmaceutical industry.Las especies de cangrejo de río identificadas como (Atya gabonensis) a lo largo del río Benue Nigeria y se capturaron y analizaron para determinar el contenido de nutrientes y antinutrientes, incluida la composición aproximada (proteína cruda, grasa cruda, fibra cruda, cenizas y contenido de humedad), así como vitamina A,Componentes de vitamina B, vitamina C, vitamina D, vitamina E, vitamina K y concentraciones de minerales seleccionadas. Además, también se examinaron algunos antinutrientes importantes en los cangrejos de río. La composición aproximada mostró que el contenido de humedad fue (9.54%), la proteína fue (7.46%), la fibra cruda fue (5.60%), la grasa fue (1.57%) y la ceniza fue (2.47%) respectivamente. Se encontró que era rico en proteínas y una cantidad considerablemente alta de contenido de humedad. El análisisde composición antinutrientes reveló la presencia de saponina (0,471 mg / 100 g), alcaloide (3,905 mg / 100 g), flavonoide (0,675 mg / 100 g), tanino (0,017 mg / 100 g), fitato (0,060 mg / 100 g), Oxalato (0,005 mg / 100 g) y otros, todos los cuales estánpor debajo del nivel tóxico. Para las composiciones de minerales y vitaminas, el potasio fue significativamente (P> 0.05) más alto que el hierro, zinc, magnesio, calcio y fósforo, mientras que la vitamina C fue (4.920 mg / 100g) que es más alta que todas las demás vitaminas evaluadas. Sobre la base de estos hallazgos, se recomienda el consumo de cangrejo de río (Atya gabonensis) y para su posterior investigación como materia prima potencial para la industria farmacéutica
Process Water Management and Seepage Control in Tailings Storage Facilities: Engineered Environmental Solutions Applied in Chile and Peru
No full textIn the past thirty years many mining projects in Chile and Peru have used: (i) polymeric geomembranes and (ii) design-and-build cutoff trenches, plastic concrete slurry walls, and grout curtain systems to control seepage at tailings storage facilities (TSFs). Geosynthetics are a viable alternative at a TSF dam for clay cores or impermeable materials, mainly because of their marked advantages in cost, installation, and construction time. This article describes the use of geosynthetics liners and cutoff trench-plastic concrete slurry walls-grout curtain systems in TSF dams in Chile and Peru mining, with the objective to decrease seepage to the environment, considering different dam material cases such as: cycloned tailings sand dams, borrow dams, and mine waste rock dams. Finally, this article discusses aspects of geosynthetic technology acceptance in the local regulatory frameworks, lessons learned, and advances. It focuses on the use and implementation of geosynthetics in TSFs in Chile and Peru, which have some of the highest TSF dams in the world, as well as a wet environment, dry environment, extreme topography, and severe seismic conditions. These conditions constitute a challenge for manufacturers, engineers, and contractors, who must achieve optimal technical solutions, while being environmentally aware and economic