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1.
Ecotoxicol Environ Saf ; 147: 401-406, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28888123

RESUMEN

In this work five different imidazolium based ionic liquids, namely: 1-(2-oxybutyl)-3-methylimidazolium chloride, [C2OC2mIm][Cl]; 1-(2-oxypropyl)-3-methylimidazolium chloride, [C1OC2mIm][Cl]; 1-(3-hydroxypropyl)-3-ethylimidazolium chloride, [OHC3eIm][Cl]; 1-(3-hydroxypropyl)-3-methylimidazolium chloride, [OHC3mIm][Cl]; 1-(2-hydroxyethyl)-3-methylimidazolium chloride, [OHC2mIm][Cl], together with commercial 1-butyl-3-methylimidazolium chloride, [bmim][Cl] and synthesized protic imidazolium chloride, [Im][Cl], were prepared and their toxicity examined towards wheat and barley germination and growth. Introduction of the polar groups (in the form of hydroxyde and/or ether group) in the alkyl side chain of the imidazolium cation and their influence on the reduction of the ionic liquid's toxicity is demonstrated. The results indicate that toxicity of oxygen functionalized ILs is significantly lower against wheat comparing to non-functionalized analogues. In the case of barley, influence on germination follow the same trend as in the case of wheat, but for seedlings growth different trend is observed with more pronounced toxicity of ether functionalized ILs. From these results it was also shown that alkylation in the position N-3 atom of the imidazole significantly reduces toxicity of cation.


Asunto(s)
Germinación/efectos de los fármacos , Hordeum/efectos de los fármacos , Imidazoles/toxicidad , Líquidos Iónicos/toxicidad , Oxígeno/química , Triticum/efectos de los fármacos , Cationes , Hordeum/crecimiento & desarrollo , Imidazoles/síntesis química , Imidazoles/química , Líquidos Iónicos/síntesis química , Líquidos Iónicos/química , Estructura Molecular , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Triticum/crecimiento & desarrollo
2.
Appl Microbiol Biotechnol ; 99(12): 4983-96, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25957155

RESUMEN

The massive application of chemical fertilizers to support crop production has resulted in soil, water, and air pollution at a global scale. In the same time, this situation escalated consumers' concerns regarding quality and safety of food production which, due to increase of fertilizer prices, have provoked corresponding price increase of food products. It is widely accepted that the only solution is to boost exploitation of plant-beneficial microorganisms which in conditions of undisturbed soils play a key role in increasing the availability of minerals that otherwise are inaccessible to plants. This review paper is focused on the employment of microbial inoculants and their production and formulation. Special attention is given to biotechniques that are not fully exploited as tools for biofertilizer manufacturing such as microbial co-cultivation and co-immobilization. Another emerging area includes biotechnological production and combined usage of microorganisms/active natural compounds (biostimulants) such as plant extracts and exudates, compost extracts, and products like strigolactones, which improve not only plant growth and development but also plant-microbial interactions. The most important potential and novel strategies in this field are presented as well as the tendencies that will be developed in the near future.


Asunto(s)
Inoculantes Agrícolas/química , Química Farmacéutica/métodos , Fertilizantes/análisis , Microbiología Industrial/métodos , Plantas/microbiología , Inoculantes Agrícolas/crecimiento & desarrollo , Inoculantes Agrícolas/metabolismo , Fertilizantes/microbiología
3.
J Agric Sci ; 156(5): 658-672, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30369629

RESUMEN

A probabilistic crop forecast based on ensembles of crop model output estimates, presented here, offers an ensemble of possible realizations and probabilistic forecasts of green water components, crop yield and green water footprints (WFs) on seasonal scales for selected summer crops. The present paper presents results of an ongoing study related to the application of ensemble forecasting concepts in crop production. Seasonal forecasting of crop water use indicators (evapotranspiration (ET), water productivity, green WF) and yield of rainfed summer crops (maize, spring barley and sunflower), was performed using the AquaCrop model and ensemble weather forecast, provided by The European Centre for Medium-range Weather Forecast. The ensemble of estimates obtained was tested with observation-based simulations to assess the ability of seasonal weather forecasts to ensure that accuracy of the simulation results was the same as for those obtained using observed weather data. Best results are obtained for ensemble forecast for yield, ET, water productivity and green WF for sunflower in Novi Sad (Serbia) and maize in Groß-Enzersdorf (Austria) - average root mean square error (2006-2014) was <10% of observation-based values of selected variables. For variables yielding a probability distribution, capacity to reflect the distribution from which their outcomes will be drawn was tested using an Ignorance score. Average Ignorance score, for all locations, crops and variables varied from 1.49 (spring barley ET in Groß-Enzersdorf) to 3.35 (sunflower water productivity in Groß-Enzersdorf).

4.
Mol Plant Microbe Interact ; 10(1): 95-101, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9002273

RESUMEN

Three cDNAs (ext3, ext127, and ext26), originally isolated by differential screening from a root-hair cDNA library of Vigna unguiculata, were found to encode extensin-like cell wall proteins. Transcripts homologous to these cDNAs were only detected in root hairs where mRNA levels decreased 1 day after inoculation with rhizobia. This coincided with the onset of root-hair deformation, the first morphological step in the Rhizobium-legume interaction. Decreases in transcript levels following inoculation with wild-type Rhizobium sp. NGR234 were more pronounced than with NGR delta nodABC, a mutant deficient in Nod-factor production. Inoculation with a rhizobial strain carrying a mutation in a gene encoding a transcriptional activator for nod genes (NGR delta nodD1) did not repress mRNA levels, indicating that a second nodulation signal may be present that is nodD dependent. Application of purified NodNGR factors only affected transcript levels of ext3. The genomic locus of the gene homologous to ext26 (Ext26G) was cloned. In the 5' flanking region, several potential TATA boxes and CAP signals were identified. Part of the promoter region shares homology with the Pisum sativum seed lectin promoter and the Nicotiana tabacum nitrate reductase promoter region. Nonetheless, the function of these homologous regions in gene regulation is unknown.


Asunto(s)
Glicoproteínas/biosíntesis , Fenómenos Fisiológicos de las Plantas , Plantas/microbiología , Rhizobium/fisiología , Secuencia de Aminoácidos , Secuencia de Bases , Regulación de la Expresión Génica de las Plantas , Biblioteca Genómica , Glicoproteínas/química , Datos de Secuencia Molecular , Proteínas de Plantas/biosíntesis , Raíces de Plantas , ARN Mensajero/biosíntesis , Rhizobium/genética , Especificidad de la Especie , Transcripción Genética
5.
Int Angiol ; 30(5): 434-40, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21873974

RESUMEN

AIM: The aim of this paper was to determine the role of ultrasonographic examination in acute progressive thrombophlebitis (APT) of great saphenous vein (GSV) and its impact in considering indications for urgent surgical treatment. MEHODS: In this retrospective study, out of 141 consecutive patients operated due to APT of GSV above the knee, 63 were examined by ultrasonography prior surgery. RESULTS: Out of 63 operated patients, in 38 duplex ultrasonography (DUS) revealed that proximal level of phlebitic process was more than 5 cm higher than the one found during physical examination (60.3%). In this group, the mean difference between DUS and clinical finding was 8.5±3.5 cm. In 25 patients there were no differences greater than 5 cm found between DUS and physical examination (39.7%). There was statistically highly significant difference between DUS and physical examination findings (χ2=6.5, P<0.01). CONCLUSION: This study revealed significant difference between ultrasonographic and physical findings in patients with APT of GSV. DUS presented as reliable diagnostic method in examining, course-following and making decision for operative treatment of these patients.


Asunto(s)
Vena Safena/diagnóstico por imagen , Vena Safena/cirugía , Tromboflebitis/diagnóstico por imagen , Tromboflebitis/cirugía , Ultrasonografía Doppler en Color , Procedimientos Quirúrgicos Vasculares , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Distribución de Chi-Cuadrado , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Físico , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Serbia , Resultado del Tratamiento
6.
Vojnosanit Pregl ; 58(5): 463-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11769409

RESUMEN

General reaction of an organism (survival, body temperature, hematocrit, glycemia) was followed in Mongolian gerbils subjected to isolated head injury (brain ischemia--LD5), to peripheral injury (ischemia of both hind limbs--LD20), and to combined injury (head injury + peripheral injury). In the early period (1 hour) after the injury, parameters of oxidative stress were followed in the brain cortex (superoxide anion, index of lipid peroxidation, activity of superoxide dismutase and glutathione reductase). Obtained results indicate that the combined peripheral and central injury of low lethality leads to the worsening of general response of the organism with high lethality of experimental animals (LD80). Likewise, the increased cortical production of superoxide anion and index of lipid peroxidation, as well as the disturbances of antioxidative enzymes activity suggest on an important role of brain oxidative stress in the development of the syndrome of mutual aggravation in animals subjected to combined injury.


Asunto(s)
Encéfalo/metabolismo , Corteza Cerebral/metabolismo , Traumatismo Múltiple/metabolismo , Estrés Oxidativo , Animales , Temperatura Corporal , Isquemia Encefálica/metabolismo , Femenino , Gerbillinae , Glutatión Reductasa/metabolismo , Hematócrito , Miembro Posterior/irrigación sanguínea , Isquemia/metabolismo , Peroxidación de Lípido , Masculino , Traumatismo Múltiple/fisiopatología , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismo
7.
Vojnosanit Pregl ; 58(3): 237-42, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11548547

RESUMEN

The etiology of neuronal death in neurodegenerative diseases, including Huntington's disease (HD), is still unknown. There could be a complex interplay between altered energy metabolism, excitotoxicity and oxidative stress. Unilateral administration of quinilonic acid (QA), NMDA agonist, in rat striatum in a single dose of 150 nM was used as a model of HD. The other two groups of animals were pretreated immediately before QA application with nerve growth factor (NGF) and fibroblast growth factor (FGF), respectively. Control group was treated with 0.9% NaCl in the same manner. Content of total glutathione was not altered in the striatum and hippocampus of QA-treated animals, as well as in the groups pretreated with neurotrophic factors (NF), compared to controls. Content of reduced glutathione, a key antioxidant, was mutually depleted in the striatum and hippocampus of each experimental group. The reduced/total glutathione ratio was decreased in the QA-treated animals, but nearby or over the controls in each structure of the NF-treated groups. These results support the hypothesis that oxygen-free radicals contribute to the excitotoxic neuronal injury, and also that NF could be the potential neuroprotective agents in HD. Moreover, activity of cytochrome c oxidase, the last component in the mitochondrial respiratory chain, was mutually increased in each structure of QA-treated animals. This increase was less pronounced in the NF-treated groups. Striatal lesions led to the loss of tonic inhibitory inputs to the globus pallidus with consequent increase in the activity of GABAergic efferent pallidal neurons, suggesting that NF could functionally repair the altered striopallidal pathway.


Asunto(s)
Cuerpo Estriado/metabolismo , Hipocampo/metabolismo , Enfermedad de Huntington/metabolismo , Estrés Oxidativo , Animales , Antioxidantes/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Metabolismo Energético , Factores de Crecimiento de Fibroblastos/farmacología , Factores de Crecimiento de Fibroblastos/fisiología , Glutatión/metabolismo , Enfermedad de Huntington/inducido químicamente , Factor de Crecimiento Nervioso/farmacología , Factor de Crecimiento Nervioso/fisiología , Ácido Quinolínico , Ratas , Ratas Wistar
8.
Phys Rev Lett ; 90(15): 150801, 2003 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-12732023

RESUMEN

Over five years, we have compared the hyperfine frequencies of 133Cs and 87Rb atoms in their electronic ground state using several laser-cooled 133Cs and 87Rb atomic fountains with an accuracy of approximately 10(-15). These measurements set a stringent upper bound to a possible fractional time variation of the ratio between the two frequencies: d/dt ln([(nu(Rb))/(nu(Cs))]=(0.2+/-7.0)x 10(-16) yr(-1) (1sigma uncertainty). The same limit applies to a possible variation of the quantity (mu(Rb)/mu(Cs))alpha(-0.44), which involves the ratio of nuclear magnetic moments and the fine structure constant.

9.
Phys Rev Lett ; 92(23): 230802, 2004 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-15245149

RESUMEN

We have remeasured the absolute 1S-2S transition frequency nu(H) in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a limit of (-29+/-57) Hz for the drift of nu(H) with respect to the ground state hyperfine splitting nu(Cs) in 133Cs. Combining this result with the recently published optical transition frequency in 199Hg+ against nu(Cs) and a microwave 87Rb and 133Cs clock comparison, we deduce separate limits on alpha/alpha=(-0.9+/-2.9) x 10(-15) yr(-1) and the fractional time variation of the ratio of Rb and Cs nuclear magnetic moments mu(Rb)/mu(Cs) equal to (-0.5+/-1.7) x 10(-15) yr(-1). The latter provides information on the temporal behavior of the constant of strong interaction.

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