Determinación del potencial promotor del crecimiento vegetal de Azotobacter spp. aislados de la rizósfera de malezas en cultivos de maíz (Zea mays L.)

The chemical fertilizer represents for 20 and 30 % of cost the production a crop, used correctly increase productivity and profitability, however, each year increase the among of fertilizer to apply, due to deficiency of soil adsorption and absorption by the plant. Beging maize the third most important crop in Peru, with a significant impact on economic and social activity in 2014, only 40% of the offered maize corresponded of the production nacional. 37 weeds were identified associated with crops of maize from agricultural fields Monsefú districts and Reque, Lambayeque Region, with 68% being dicotyledonous against monocots with 32%. Bacteria were isolated from the rhizosphere of weeds, getting 305 pure cultures of bacteria, 133 of which (43.7%) were identified as Azotobacter spp. Investigated the biochemical reaction in nitrate reduction, utilization of sucrose, glucose, maltose, mannitol, rhamnose, glycerol and sorbitol. Identifying A. vinelandii (58%), A. paspali (13%), A. armeniacus (8%), A. nigricans (8%) and 13 cultives not the species was identified. With this cultives pure of Azotobacter spp. native was quantified to 36.03 ppm of fixed nitrogen as ammonia; 60.75 ppm of indole acetic acid and 6.06 ppm solubilized phosphorus was also determined the activity antagonistic to Fusarium verticillioides, proteolytic and chitinolytic. 20% of Azotobacter spp. native did not affect the emergence of simple hybrid hard yellow corn 144 agriculture, 33% positively affected and 47% negatively affected. In turn, none Azotobacter spp. affect negatively survival. The potential of the plant growth promoter of Azotobacter spp. isolated from weeds in maize crops in the region of Lambayeque been demonstrated.Los fertilizantes químicos representan entre 20% y 30% de los costos de producción de un cultivo, utilizados correctamente incrementan la productividad y rentabilidad; sin embargo, cada año aumenta la cantidad de fertilizantes por aplicar, debido a la deficiencia de adsorción en el suelo y absorción por la planta. Siendo el maíz el tercer cultivo de importancia en Perú, con un impacto significativo en la actividad económica y social, en el 2014, solo el 40% del maíz ofertado correspondió a la producción nacional. En busca de alternativas para disminuir el uso de fertilizantes químicos se realizan investigaciones con denominadas rizobacterias promotoras del crecimiento vegetal (PGPR, por sus siglas en ingles). Se identificaron 37 malezas en cultivos de maíz procedentes de campos agrícolas de los distritos de Monsefú y Reque, Región Lambayeque, siendo dicotiledóneas predominantes con 68 % con respecto a monocotiledóneas con 32%. Las bacterias se aislaron de la rizósfera de malezas, obteniendo 305 cultivos puros de bacterias, de los cuales 133 cultivos puros (43,7%) se identificaron como Azotobacter spp., investigándose su reacción bioquímica en reducción de nitratos, utilización de sacarosa, glucosa, maltosa, manitol, ramnosa, glicerol y sorbitol, identificándose A. vinelandii (58%), A. paspali (13%), A. armeniacus (8%), A. nigricans (8%) y en 13 cultivos no se identificó la especie. Con los cultivos Azotobacter spp. se cuantificó hasta 36,03 ppm de nitrógeno fijado como amonio; 60,75 ppm de ácido indol acético y 6,06 ppm de fósforo solubilizado, se determinó actividad antagónica contra Fusarium verticillioides, proteolítica y quitinolítica y. El 20% de Azotobacter spp. no afectó la emergencia de maíz amarillo duro hibrido simple AGRI- 144, el 33 % la afectó positivamente y el 47% la afectó negativamente. A su vez, ningún Azotobacter spp. afectó la sobrevivencia. Demostrándose el potencial promotor del crecimiento vegetal de Azotobacter spp. aislados de malezas en cultivos de maíz en la Región de Lambayeque

Determinación del potencial promotor del crecimiento vegetal de las enterobacterias aisladas de la rizósfera del cultivo de maíz (Zea mays L.)

The yellow maize is the third most important crop in Peru and part of the chain maize-poultry-pig, significant impact on the national economic and social activity, however, in 2011, only 40% of the corn offered corresponded to the domestic industry. Looking for alternatives to reduce the use of chemical fertilizers, have performed investigations with plant growth promoting rhizobacteria. Bacteria were isolated from the rhizosphere of maize from districts Monsefú and Reque, Lambayeque. Dilution was made into sterile saline 0.87% NaCl w/v and plated on MacConkey agar, incubating at 30°C for 48 hours. 269 pure cultures of bacteria were obtained, the biochemical reaction was investigated in agar Triple sugar iron agar Iron Lysine, agar Citrate Simons, peptone broth, red broth methyl Voges-Proskauer and nitrate broth, was identified 66% as Enterobacteriaceae of genera Pantoea (49%), Klebsiella (17%), Kluyvera (16%), Serratia (11%), Citrobacter (4%) and Hafnia (3%). The native enterobacteria were quantified to 31.67 ppm of fixed nitrogen as ammonia; 54.25 ppm indole acetic acid and 4,78 ppm solubilized phosphorus, activity proteolytic and chitinolytic and antagonistic activity of Fusarium verticillioides were also determined. 16% of native enterobacteria did not affect the emergence of hard yellow maize, 77% affected positively and 7% affected negatively. In turn, none bacteria affected survival. Was demonstrated the potential plant growth promoter of enterobacteria isolated from field crops in the region of Lambayeque.El maíz amarillo duro es el tercer cultivo en importancia en el Perú y forma parte de la cadena maíz-avicultura-porcicultura, de impacto significativo en la actividad económica y social nacional, sin embargo, en el 2011, solo el 40% del maíz ofertado correspondió a la producción nacional. En busca de alternativas para disminuir el uso de fertilizantes químicos se realizan investigaciones con denominadas rizobacterias promotoras del crecimiento vegetal. Las bacterias se aislaron de la rizósfera de maíz procedentes de campos agrícolas de los distritos de Monsefú y Reque, Región Lambayeque. Se realizó una dilución en solución salina esterilizada: 0,87% NaCl, p/v y se sembró en agar Mac Conkey, incubando a 30°C por 48 horas. Se obtuvieron 269 cultivos puros de bacterias, se investigó su reacción bioquímica en agar Hierro Triple Azúcar, agar Hierro Lisina, agar Citrato de Simons, caldo peptonado, caldo rojo de metilo Voges-Proskauer y caldo nitrato, identificándose 66% como enterobacterias de los géneros Pantoea (49%), Klebsiella (17%), Kluyvera (16%), Serratia (11%), Citrobacter (4%) y Hafnia (3%). Con las enterobacterias nativas se cuantificó hasta 31,67 ppm de nitrógeno fijado como amonio; 54,25 ppm de ácido indol acético y 4,78 ppm de fósforo solubilizado, así como también se determinó actividad proteolítica, quitinolítica y antagónica a Fusarium verticillioides. El 16% de enterobacterias nativas no afectó la emergencia de maíz amarillo duro hibrido simple AGRI- 144, el 77% la afectó positivamente y el 7% la afectó negativamente. A su vez, ninguna bacteria afectó la sobrevivencia. Se demostró el potencial promotor del crecimiento vegetal de las enterobacterias aisladas de campos de cultivos de la Región de Lambayeque

Comparación de varios métodos para determinar requerimientos de cal en algunos suelos colombianos.

Se probaron varios métodos rápidos para determinar requerimientos de cal en algunos suelos ácidos y establecer el mejor método para efectuar las recomendaciones de encalamiento. Este trabajo se realizó en el Laboratorio de Suelos del ICA en Palmira (Valle del Cauca) usando 6 suelos de diferentes regiones agrícolas del país, cuya textura varió desde franco-arenosa hasta arcillosa, una reacción fuertemente ácida, un contenido de Al intercambiable desde 0.5 hasta 3.6 me/100 g de suelo y un porcentaje de materia orgánica que varió de 2.8 a 21.4 por ciento. El método de acidez intercambiable puede ser el más aconsejable para determinar los requerimientos de cal, siguiendo en su orden los métodos de Dunn, el de la solución amortiguadora y el del acetato de calcio. El método de Woodruff se encontró inapropiado para este fin. Las ventajas del método de acidez intercambiable que se reflejaron al funcionar bien, para alcanzar un pH de 5.7 a 6, además de la neutralización de un alto porcentaje del Al intercambiable y del posible adecuado suministro de Ca al suelo, así como también en la economía de tiempo y de material utilizado en su determinación. Los métodos de Dunn, el de la solución amortiguadora y el de acetato de calco, correlacionaron bien para el control del p

La artroscopia de rodilla: experiencia de 474 casos

El objetivo de este trabajo es dar a conocer los resultados de un estudio de 474 artroscopias realizadas en nuestro Servicio de Cirugía Ortopédica y Traumatología desde el mes de enero 1988 hasta agosto 1992. La edad media de los pacientes fue de 32 años, con una mayor incidencia en el sexo masculino (73%). La patología más frecuente correspondió a la meniscopatía interna (48%). Tuvimos una estancia media hospitalaria de 3 días, apreciándose una relación inversa entre ésta y la edad del paciente. La complicación más habitual en el post-operatorio fue el derrame sinovial (3%) siendo necesaria al artrocentesis para su desaparición en el plazo de 1-2 semanas.This work was aimed at presenting the results of 474 diagnostic artroscopies of the knee performed in our Department of orthopaedic surgery from January 1988 to August 1992. The mean age of the patients was 32 years. There was a greater incidence in males (73%). The most frequent pathologic finding was medial meniscopathy (48%). The mean period of hospitalization was 3 days. There was an opposite relationship betwen the hospitalization period and the age of the patient. As complications, synovial effusion was found in 3% of cases, synovial fluid evacuation been necessary

Oral Consumption of Bread from an RNAi Wheat Line with Strongly Silenced Gliadins Elicits No Immunogenic Response in a Pilot Study with Celiac Disease Patients

Celiac disease (CD) is a genetically predisposed, T cell-mediated and autoimmune-like disorder caused by dietary exposure to the storage proteins of wheat and related cereals. A gluten-free diet (GFD) is the only treatment available for CD. The celiac immune response mediated by CD4+ T-cells can be assessed with a short-term oral gluten challenge. This study aimed to determine whether the consumption of bread made using flour from a low-gluten RNAi wheat line (named E82) can activate the immune response in DQ2.5-positive patients with CD after a blind crossover challenge. The experimental protocol included assessing IFN-γ production by peripheral blood mononuclear cells (PBMCs), evaluating gastrointestinal symptoms, and measuring gluten immunogenic peptides (GIP) in stool samples. The response of PBMCs was not significant to gliadin and the 33-mer peptide after E82 bread consumption. In contrast, PBMCs reacted significantly to Standard bread. This lack of immune response is correlated with the fact that, after E82 bread consumption, stool samples from patients with CD showed very low levels of GIP, and the symptoms were comparable to those of the GFD. This pilot study provides evidence that bread from RNAi E82 flour does not elicit an immune response after a short-term oral challenge and could help manage GFD in patients with CD.This research was funded by The Spanish Ministry of Science and Innovation, Agencia Estatal de Investigación (Project PID2019-110847RB-I00), Consejería de Transformación Económica, Industria, Conocimiento y Universidades, Junta de Andalucía (Project P20_01005), and “ERDF A way of making Europe”, by the “European Union”

Films of Mn12-acetate deposited by low-energy laser ablation

Thin films of the molecular magnet Mn12-acetate, [Mn12 O12(CH3COO)16 (H2O)4] 2CH3COOH 4H2O, have been prepared using a laser ablation technique with a nitrogen laser at low laser energies of 0.8 and 2 mJ. Chemical and magnetic characterizations show that the Mn12-acetate cores remain intact and the films show similar magnetic properties to those of the parent molecular starting material. In addition, the magnetic data exhibit a peak in the magnetization at 27 K indicating the creation of an additional magnetic phase not noted in previous studies of crystalline phases.Comment: 8 pages, 5 figures, In Press - J. Mag. Mag. Ma

Oral consumption of bread from an RNAi wheat line with strongly silenced gliadins elicits no immunogenic response in a pilot study with celiac disease patients

Celiac disease (CD) is a genetically predisposed, T cell-mediated and autoimmune-like disorder caused by dietary exposure to the storage proteins of wheat and related cereals. A gluten-free diet (GFD) is the only treatment available for CD. The celiac immune response mediated by CD4+ T-cells can be assessed with a short-term oral gluten challenge. This study aimed to determine whether the consumption of bread made using flour from a low-gluten RNAi wheat line (named E82) can activate the immune response in DQ2.5-positive patients with CD after a blind crossover challenge. The experimental protocol included assessing IFN-γ production by peripheral blood mononuclear cells (PBMCs), evaluating gastrointestinal symptoms, and measuring gluten immu-nogenic peptides (GIP) in stool samples. The response of PBMCs was not significant to gliadin and the 33-mer peptide after E82 bread consumption. In contrast, PBMCs reacted significantly to Standard bread. This lack of immune response is correlated with the fact that, after E82 bread consump-tion, stool samples from patients with CD showed very low levels of GIP, and the symptoms were comparable to those of the GFD. This pilot study provides evidence that bread from RNAi E82 flour does not elicit an immune response after a short-term oral challenge and could help manage GFD in patients with CD.Ministerio de Ciencia e Innovación PID2019-110847RB-I00Junta de Andalucía P20_0100

Constraining the pˉ/p\bar{p}/p Ratio in TeV Cosmic Rays with Observations of the Moon Shadow by HAWC

An indirect measurement of the antiproton flux in cosmic rays is possible as the particles undergo deflection by the geomagnetic field. This effect can be measured by studying the deficit in the flux, or shadow, created by the Moon as it absorbs cosmic rays that are headed towards the Earth. The shadow is displaced from the actual position of the Moon due to geomagnetic deflection, which is a function of the energy and charge of the cosmic rays. The displacement provides a natural tool for momentum/charge discrimination that can be used to study the composition of cosmic rays. Using 33 months of data comprising more than 80 billion cosmic rays measured by the High Altitude Water Cherenkov (HAWC) observatory, we have analyzed the Moon shadow to search for TeV antiprotons in cosmic rays. We present our first upper limits on the $\bar{p}/p$ fraction, which in the absence of any direct measurements, provide the tightest available constraints of $\sim1\%$ on the antiproton fraction for energies between 1 and 10 TeV.Comment: 10 pages, 5 figures. Accepted by Physical Review