996 resultados para Concentration technique


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წარმოდგენილია მიწისპირა ოზონის საშუალოწლიური მონაცემების და სხვადასხვა ბალიანობის ხილვადობის სიშორის მქონე დღეების რიცხვს შორის კორელაციური და რეგრესიული კავშირის გამოკვლევის შედეგები 9, 12 და 15 საათზე დაკვირვებებისათვის.

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In Tbilisi according to the data of the complex monitoring of light ions concentration, radon and sub-micron aerosols the effect of feedback of intensity of ionizing radiation with the light ions content in atmosphere is discovered.

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Magdeburg, Univ., Med. Fak., Diss., 2012

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WATER-CULTURE EXPERIMENTS. Two water-culture experiments were carried out to study the absorption and the translocation of radiozinc in young coffee plants as influenced by two factors, namely, concentration of heavy metals (iron, man ganese, copper and molybdenum) and method of application. Inert zinc was supplied at an uniform rate of 0. 05 p. p. m.; the levels of iron supply were 0, 1.0, and 10.0 p. p.m.; manganese was supplied in three doses 0, 0.5, and 5.0 p. p.m.; copper- 0, 0. 02, and 0. 2 p. p. m.; molybdenum- 0, 0. 01, and 0. 1 p. p. m. When applied to the nutrient solution the activity os the radiozinc (as zinc chloride) was 0. 15 microcuries per plant. In the study of the leaf absorption, Zn65 was supplied at the level of 0. 10 microcuries per plant; in this case the radioative material was brushed either on the lower or on the upper surface or both two pairs of mature leaves. The absorption period was 8 weeks. The radioactivity assay showed the following results: 1 - Among the heavy metals herein investigated the iron concentration did not affect the uptake of the radiozinc; by raising the level of Mn, Cu and Mo ten times, the absorption dropped to 50 per cent and even more when compared with the control plants; when, however, these micronutrients were omitted from the nutrient solution, an increase in the uptake of zinc was registered in the minus Cu treatment only. The effects of high levels of Mn, Cu and Mo probably indicate an interionic competition for a same site on a common binding substance in the cell surface. 2 - The absorption of the radiozinc directly applied to the leaf surface reached levels as high as 8 times that registered when the root uptake took place. Among the three methods of application which have been tried, brushing the lower surface of the leaves proved to be the most effective; this result is easily understood since the stomatal openings of the coffee leaves an preferentially located in the lower surface - in this treatment, about 40 per cent of the activity was absorved and around 12 per cent were translocated either to the old or to the newer organs. Chemical analyses for heavy metals, were carried out only in the plants received Zn65Cl2 in the nutrient solution; the results were as follows; 1 - Control plants had, per 1,000 gm, of dry weight the following amounts in mg.: Zn- 48 in the roots and 29 in the tops; Fe- 165 in the roots and 9 in the tops; Mn- 58 in the roots and 15 in the tops, Cu- 15 in the roots and 1. 2 in the tops; Mo- 2. 8 in the roots and 0. 45 in the tops. 2 - The effect of different levels of micronutrients in the composition of the plants can be summarized as follows: Fe and Zn- when omitted from the nutrient solution, the iron and zinc contents in the roots decreased, no variation being noted in the tops; the higher dosis caused an accumulation in the roots but no apparent effect in the tops; Mn- by omitting this micronutrient a decrease in its content in the roots was noted, where as the concentration in the tops was the same; Mo- no variation in roots and tops contents when molybdenum was omitted; higher dosis of manganese and molybdenum increased the amounts formed both in the roots and in the tops. 3 - The influence of the different concentrations of micronutrients heavy metals on the zinc content of the coffee plants can be described by saying that: Fe and Mo- no marked variation; Mn- no effect when omitted, reduced amount when the high dosis was supplied; Mn- when the plants did not receive manganese the zinc content in roots and tops was the same as in the control plants; a decrease in the zinc content of the total plant occurred when the high dosis was employed; Cu -the situation is similar to that described for manganese. Hence, results showed by the chemical analyses roughly correspond to those of the radioactivity assay; the use of the tracer technique, however, gave best informations along this line. SOIL-POTS EXPERIMENTS. The two types of soils which when selected support the most extensive coffee plantations in the State of São Paulo, Brazil: "arenito de Bauru", a light sandy soil and "terra roxa legitima", a red soil derived from basalt. Besides NPK containing salts, the coffee plants were given two doses of inert zinc (65 and 130 mg ZnCl2 per pot) and radiozinc at a total activity of 10(6) counts/minute. The results of the countings can be summarized as follows: 1 - When plants were grown in "arenito de Bauru" the activity absorbed as per cent of the total activity supplied was not affected by the dosis of inert zinc. The highest value found was around 0. 1 per cent. 2 - For the "terra roxa" plants, the situation is almost the same; there was, however, a slight increase in the absorption of the radiozinc when 130 mgm of ZnClg2 was given: a little above 0. 2 per cent of the activity supplied was absorbed. The results clearly show that the young coffee plants practically did not absorb none of the zinc supplied; two reasons at least could be pointed out to explain such a fact: 1 - Zinc fixation by an exchange with magnesium or by filling holes in the octahedral layer of aluminosilicates, probably kaolinite; 2 - No need for fertilizer zinc in the particular stage of life cycle under which the experiment was set up. The data from chemical analysis are roughly parallel to the above mentioned. When one attempts to compare - by taking data herein reported zinc uptake from nutrient solution, leaf brushing or from fertilizers in the soil, a practical conclusion can be drawn: the control of zinc deficiency in coffee plants should not be done by adding the zinc salts to the soil; in other words: the soil applications used so extensively in other countries seem not to be suitable for our conditions; hence zinc sprays should be used wherever necessary.

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Magdeburg, Univ., Fak. für Maschinenbau, Diss., 2015

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In order to obtain the following informations: a) dry matter production and extraction of nutrients by the fruits at different ages; b) dry matter production and extraction of nutrient by the leaves and "trunk + branches" collected at the flowering stage; c) dry matter production and export of nutrients by pruning (leaves and branches) at the begining dormant stage; A trial was conducted on Latossolo Vermelho Escuro Orto group (Orthox) at Buri, São Paulo State, Brazil. The material was collected from 'Ohio Beauty' and 'Brazil' apples grafted on 'Doucin' 1-2; 3-4; 4-5 and 6-7 years old. The main conclusions were as follows: a) differences were observed on dry matter production by two varieties at the different stages of growth; b) differences were also observed between the two varieties on the matter production in the leaves and "trunk + branches" at the flowering stage, as well as by the leaves and branches pruned at the begining of dormant stages; c) differences were observed betwen the two varieties concerning to nutrient concentration (on dry matter basis) on the fruits collected at different stages of growth. Same results were observed on leaves and "trunk + branches" collected at flowering period; d) differences were observed on the exportation of the nutrients referring to growth period of fruit; e) at the flowering and dormant period, differences were observed on the contents of nutrients in the leaves, 'trunk + branches', on the two varieties; f) the nutrient exportation by the fruits obyed the following order: K>N>P>S>Ca>Mg>Fe>B > Cu > Mn > Zn > Mo; g) the nutrient extration by the aerial part the apple trees obyed the following order: N > K > Ca > Mg > P > S > Fe > B > Cu = Mn = Zn.

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On an apple grove situated at Buri, State of São Paulo, fruits were collected from trees 1-2; 3-4; 4-5, and 6 - 7 years old. The fruits were analysed for N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn. The authors concluded: a) the concentrations of the nutrients in the fruits differ according to the variety, age of the tree and age of the fruit; b) the concentrations of nutrients decrease with aging of the fruits; c) the concentrations of the macronutrients obey the following order: N>K>P>Ca>S> Mg; d) for the micronutrients, the following order was ob -served: Fe > B > Mn > Cu > Zn.

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I) the A. presents a method developed for the preparation of thick blood films, specially old desiccated smears. The observations are based on the experience of more than 53000 blood samples collected in the laboratory of the “Serviço de Malaria do Nordeste” as well as in the research department of the “Serviço de Malaria da Baixada Fluminenese”. II) As in introductory matter, he emphasizes the value of the obstacles presented by overdrying of the thick blood films occurring systematically in great malaria control organizations in which the laboratory receives materials from more or less remote localities, particularly in the Brazilian northeast, in regions invaded by Anopheles gambiae. III) An analysis of the causes of failure of the methods of Chorine and Knowles recorded in the literature for such purposes is given, as well as its adaptability for the simultaneous preparation of large numbers of samples. IV) The method is based the protective action of a previous fixation by a dilute solution of formalin, which, without preventing further dehemoglobinization, prevents morphological alterations in the parasites by the action of Knowles solution which is retained in this metod without modification. V) For washing out the acids of the dehemoglobinizating solution as well as for diluting the Giemsa stain, the A. proposes a very simple technique, extremely convenient for such purpose, which consists in adding acetic acid to the distilled water in the proportion of 1 drop for each 10cc of water, and then increasing the hydrogeni-on concentration to pH 7.2 with a 2% sol. of sodium carbonate. As indicator a 0.02% solution purple-bromcresol prepared in accordante to Medalia, is used. In this reaction there is the formation of the acetic acid ↔ sodium acetate, buffer system very suitable for giving a convenient pH and for preventing the precipitation of the dye, which can be used for two or three batches of 700 or 800 slides each, without changing the staining solution. VI) – The method can be summarized as follow: For a small number of samples, Coplin’s or any other staining jar can be used. Large number of slides must be placed in groups of 10 or 15 units each, the slides being separated by a piece of cardboard, according to Barber & Komp. A) Fix in dilute formalin (2%), during 5 minutes. b) Without washing, put in Knowles solution (see the formula in the text), no more than 20 minutes. c)Two successive washings in distilled water, buffered as explained above (which can be used several times). d) Dry and stain with Giemsa solution, prepared by using 1 drop of the stain for each c. c. of buffered distilled water. Time: 1 hour. E) Was in distilled water and dry.

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Estudi elaborat a partir d’una estada al Royal Brompton Hospital, Londres, Regne Unit, durant octubre i novembre del 2006.Els beneficis de la estimulació beta-adrenèrgica en pacients amb lesió pulmonar aguda (LPA) són coneguts, però no es disposa de dades sobre el possible efecte antiinflamatori. El condensat d'aire exhalat (CAE) és una tècnica no-invasiva de recollida de mostres del tracte respiratori inferior, podent ser útil en la monitorització de patologies respiratòries. S’ha usat marcadors biològics en el CAE de pacients ventilats mecànicament amb LPA per estudiar el possible efecte antiinflamatori que el salbutamol hi podria exercir. El CAE va ser recollit abans i després de l'administració de salbutamol inahalat. Inmediatament després es va mesurar la conductivitat i el pH abans i després de la desgasificació amb heli. Es va mesurar la concentració de nitrits i nitrats. Les mostres varen ser liofilitzades i guardades a -80ºC. La concentració de leucotriè B4 es va mesurar després de la reconstitució de la mostra. Els resultats s'expressen com a mitjana (error estàndard de la mostra). No s'han detectat diferències entre els valors de CAE basals dels pacients amb LPA i els de referència de la població sana de Barcelona. Es conclou doncs que el CAE és una tècnica no invasiva que pot ser usada en la monitorització de paceints ventilats mecànicament. El salbutamol inhalat incrementa de manera significativa el pH del CAE dels paceints amb LPA, tot i que un efecte directe de la inhalació de slabutamol no pot ser desestimat.

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Abstract: The use of an enriched CO2 atmosphere in tree nurseries has been envisaged as a promising technique to increase productivity and to obtain seedlings with a higher root/shoot ratio, an essential trait to respond to water stress in Mediterranean-type ecosystems. In that framework, we have analyzed the effects of three levels of atmospheric CO2 concentration (350, 500 and 700 ppm) on the germination rate, growth and morphology of seedlings of two Mediterranean oaks used in reforestation programs: the evergreen Quercus ilex L. and the deciduous Quercus cerrioides Wilk. et Costa. CO2 enrichment increased the germination rate of Q. cerrioides (from 70±7 to 81±3 %) while it decreased that of Q. ilex (from 71±10 to 41±12 %). Seedlings of both species increased approximately 60% their total biomass in response to CO2 enrichment but at two different CO2 concentrations: 500 ppm for Q. cerrioides and 700 ppm for Q. ilex. This increase in seedlings biomass was entirely due to an augmentation of root biomass. Considering germination and biomass partitioning, an enriched CO2 atmosphere might not be appropriate for growing Mediterranean evergreen oaks, such as Q. ilex, since it reduces acorn germination and the only gains in root biomass occur at a high concentration (700 ppm). On the other hand, a moderate CO2 enrichment (500 ppm) appears as a promising nursery technique to stimulate the germination, growth and root/shoot ratio of deciduous oaks, such as Q. cerrioides. Resumen: El uso de una atmósfera enriquecida en CO2 durante la fase de vivero puede contribuir a aumentar la producción viverística, a la vez que ayudar a conseguir plántulas con una mayor relación biomasa subterránea/biomasa aérea, más adecuadas para hacer frente al severo estrés hídrico que generalmente limita el éxito de las repoblaciones en el clima Mediterráneo. En este estudio hemos analizado el efecto de tres niveles de abonado carbónico atmosférico (350, 500 y 750 ppm) en la germinación y morfología de plántulas de encina (Quercus ilex) y roble cerrioide (Quercus cerrioides). Una atmósfera enriquecida en CO2 incrementó la germinación de Q. cerrioides (de 70±7 a 81±3 %) mientras que disminuyó la de Q. ilex (de 71±10 a 41±12 %). Las plántulas de ambas especies incrementaron aproximadamente un 60% su biomasa en respuesta a una mayor concentración de CO2, aunque esta respuesta se produjo a diferentes dosis: 500 ppm en Q. cerrioides y 700 ppm en Q. ilex. El aumento en la biomasa total de las plántulas se debió enteramente a un mayor desarrollo de su sistema radical, Considerando tanto la germinación como los efectos sobre la relación biomasa subterránea/biomasa aérea, una atmósfera enriquecida en CO2 no parece ser un tratamiento adecuado para la producción en vivero de plántulas de Q.ilex, puesto que diminuye su germinación y solo aumenta su sistema radicular a dosis muy elevadas (700 ppm). Por el contrario, un aumento moderado en la concentración de CO2 (500 ppm) aparece como una técnica interesante para estimular el crecimiento y obtener plántulas de Q. cerrioides con un sistema radical más desarrollado.

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RESUMEN El aumento del CO2 atmosférico debido al cambio global y/o a las prácticas hortícolas promueve efectos directos sobre crecimiento vegetal y el desarrollo. Estas respuestas pueden ocurrir en ecosistemas naturales, pero también se pueden utilizar para aumentar la producción de algunas plantas y de algunos compuestos secundarios. El actual trabajo intenta estudiar los efectos del enriquecimiento atmosférico del CO2 bajo condiciones de invernadero en el crecimiento y la concentración y la composición de metabolitos secundarios de Taxus bacatta, Hypericum perforatum y Echinacea purpurea en condiciones ambientales mediterráneas. La fertilización del CO2 muestra perspectivas interesantes para la mejorara y aplicabilidad de técnicas hortícolas para aumentar productividad de plantas medicinales, a pesar de diferencias claras entre la especie. En general esta técnica promueve aumentos importantes y significativos en producción primaria y, en algunos casos, también en compuestos secundarios. Esto tiene una gran importancia hortícola porque la productividad a nivel de cosecha total aumenta, directamente porque se aumenta la concentración e indirectamente porque se aumenta la biomasa. SUMMARY The increase of atmospheric CO2 due to global change and/or horticultural practices promotes direct effects on plant growth and development. These responses may occur in natural ecosystems, but also can be used to increase the production of some plants and some secondary compounds. Present work tries to study the effects of atmospheric CO2 enrichment under greenhouse conditions on growth and in the concentration and composition of secondary metabolites of Taxus bacatta, Hypericum perforatum and Echinacea purpurea under Mediterranean environmental conditions. CO2 fertilization shows interesting perspectives to increase and improve horticultural techniques in order to increase plant medicinal productivity, in spite of clear differences among the species. In general this technique promotes important and significant increases in primary productivity and, in some cases, also in secondary compounds. This has a great horticultural relevance because the total productivity of this kind of products increase at crop level, directly because concentration is increased and /or indirectly because biomass is increased. RESUM L'augment del CO2 atmosfèric a causa del canvi global i/o a les pràctiques hortícoles promou efectes directes sobre creixement vegetal i el desenvolupament. Aquestes respostes poden ocórrer en ecosistemes naturals, però també es poden utilitzar per a augmentar la producció d'algunes plantes i d'alguns compostos secundaris. L'actual treball intenta estudiar els efectes de l'enriquiment atmosfèric del CO2 sota condicions d'hivernacle en el creixement i la concentració i la composició de metabòlits secundaris de Taxus bacatta, Hypericum perforatum i Echinacea purpurea en condicions ambientals mediterrànies. La fertilització del CO2 mostra perspectives interessants per a la millora i aplicabilitat de tècniques hortícoles per a augmentar productivitat de plantes medicinals, a pesar de diferències clares entre l'espècie. En general aquesta tècnica promou augments importants i significatius en producció primària i, en alguns casos, també en compostos secundaris. Això té una gran importància hortícola perquè la productivitat a nivell de collita total augmenta, directament perquè s'augmenta la concentració i indirectament perquè s'augmenta la biomassa.

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To study changes in survival, in biological activities and behavior of planorbids submitted to increased hydrostatic pressure, we developed a technique using two transparent chambers and a hydraulic piston. The apparatus permitted renewal of the liquid medium without substantial variations in pressure, thus eliminating excretion products and maintaining the desired O2 level and thereby permitting us to evaluate the effects of pressure independently of the occurrence of anoxia. Pressure was maintained without any contact of the liquid medium with compressed air, a situation which reproduced with relative fidelity what occurs in nature and assured the presence of the same amounts of gases in the two observation chambers (Control and Experimental). Biomphalaria glabrata was found to be able to survive at least 48 hours when submitted to 49.02 x 10**4 Pa (equivalent to a water depth of 48.8 m), continuing to day egg masses and showing few behavioral changes when compared with the control group.

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The presence of viral antigen in sections from formalin-fixed and paraffin-embedded human tissues was demonstrated by trypsin digestion followed by direct or indirect immunofluorescence. The specimens may be used for retrospective diagnosis. The immunofluorescence technique has to be adapted to the suspected virus infection on the basis of previous histopathology study. Variations of trypsin concentration time and temperature of incubation, expose different viral antigens and have to be previously tested for each unknown system. For measles virus detection in lung a stronger digestion has to be applied as compared to adenovirus or respiratory disease viruses in the same tisue. Flavivirus in liver tissue needs a weaker digestion. The reproducibility of the method makes it useful as a routine technique in diagnosis of virus infection.