973 resultados para Media growth
Resumo:
We study the influence of disorder strength on the interface roughening process in a phase-field model with locally conserved dynamics. We consider two cases where the mobility coefficient multiplying the locally conserved current is either constant throughout the system (the two-sided model) or becomes zero in the phase into which the interface advances (one-sided model). In the limit of weak disorder, both models are completely equivalent and can reproduce the physical process of a fluid diffusively invading a porous media, where super-rough scaling of the interface fluctuations occurs. On the other hand, increasing disorder causes the scaling properties to change to intrinsic anomalous scaling. In the limit of strong disorder this behavior prevails for the one-sided model, whereas for the two-sided case, nucleation of domains in front of the invading front are observed.
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Plant species that naturally occur in the Brazilian Caatinga(xeric shrubland) adapt in several ways to these harsh conditions, and that can be exploited to increase crop production. Among the strategic adaptations to confront low water availability, desiccation tolerance stands out. Up to now, the association of those species with beneficial soil microorganisms is not well understood. The aim of this study was to characterize Tripogon spicatusdiazotrophic bacterial isolates from the Caatingabiome and evaluate their ability to promote plant growth in rice. Sixteen bacterial isolates were studied in regard to their taxonomic position by partial sequencing of the 16S rRNA gene, putative diazotrophic capacity, in vitro indole-acetic acid (IAA) production and calcium phosphate solubilization, metabolism of nine different C sources in semi-solid media, tolerance to different concentrations of NaCl to pHs and intrinsic resistance to nine antibiotics. Finally, the ability of the bacterial isolates to promote plant growth was evaluated using rice (Oryza sativa) as a model plant. Among the 16 isolates evaluated, eight of them were classified as Enterobacteriaceae members, related to Enterobacter andPantoeagenera. Six other bacteria were related toBacillus, and the remaining two were related toRhizobiumand Stenotrophomonas.The evaluation of total N incorporation into the semi-solid medium indicated that all the bacteria studied have putative diazotrophic capacity. Two bacteria were able to produce more IAA than that observed for the strain BR 11175Tof Herbaspirillum seropedicae.Bacterial isolates were also able to form a microaerophilic pellicle in a semi-solid medium supplemented with different NaCl concentrations up to 1.27 mol L-1. Intrinsic resistance to antibiotics and the metabolism of different C sources indicated a great variation in physiological profile. Seven isolates were able to promote rice growth, and two bacteria were more efficient than the reference strainAzospirillum brasilense, Ab-V5. The results indicate the potential of T. spicatus as native plant source of plant growth promoting bacteria.
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The addition of nerve growth factor (2.5S NGF) to serum-free aggregating cell cultures of fetal rat telencephalon greatly stimulated the developmental increase in choline acetyltransferase activity. Two other neuronal enzymes, acetylcholinesterase and glutamic acid decarboxylase, showed only slightly increased activities after NGF treatment whereas the total protein content of the cultures and the activity of 2',3'- cyclic nucleotide phosphodiesterase remained unchanged. The stimulation of choline acetyltransferase was dependent on the NGF media concentrations, showing a 50% maximum effect (120% increase) at approximately 3 ng/ml (10-10 M 2.5S NGF). NGF treatments during different culture periods showed that the cholinergic neurons remained responsive for at least 19 days. The continued treatment was the most effective; however, an initial treatment for only 5 days still caused a significant stimulation of choline acetyltransferase on day 19. The observed stimulation appeared to be specific to NGF. Univalent antibody fragments (Fab) against 2.5S NGF completely abolished the NGF-dependent increase in choline acetyltransferase activity, whereas Fab fragments of control IgG were ineffective. Furthermore, angiotensin II, added in high amounts to the cultures, showed no stimulatory effect. The present results suggest that certain populations of rat brain neurons are responsive to nerve growth factor.
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Between 1995 and 2005, the Spanish economy grew at an annual average rate higher than 3,5%. Total employment increased by more than 4.9 millions. Most of this growth was in occupations related with university degrees (more than 890,000, 18% of the total employment increase) and vocational qualifications (more than 855,000, 17.5% of the total employment increase). From a sectoral perspective, the main part of this increase took place in “Real estate, renting and business activities” (K sector in NACE rev.1), “Construction” (F sector) and “Health and social sector” (N sector). This paper analyses this employment growth in an Input-output framework, by means of a structural decomposition analysis (SDA). Two kinds of results have been obtained. From a sectoral perspective we decompose employment growth into Labour requirements change, technical change and demand change. From an occupational perspective, we decompose the employment growth in substitutions effect, labour productivity effect and demand effect. The results show that, in aggregated terms, the main part of this growth is attributable to demand growth, with a small technical improvement. But the results also show that this aggregated behaviour hides important sectoral and occupational variation. The purpose of this paper is to contribute to the ongoing debate over productivity growth and what has been called the “growth model” for the Spanish economy.
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La ciudad media o intermedia europea ha sido calificada de «OGNI» (Objeto Geográfico No Identificado) por la falta de teorizaciones propias. Esta afirmación es especialmente cierta en el campo del desarrollo local, en las particularidades que juegan en el proceso de aprovechamiento de los recursos locales para crear un desarrollo endógeno. Esta investigación pretende, en primer lugar, recoger las opiniones de varios autores e instituciones para definir las características cuantitativas y cualitativas de esta realidad urbana. En segundo lugar, se quiere contextualizar la ciudad media en el territorio europeo y en las políticas a esta escala. Finalmente, se describen tres ejemplos de desarrollo local en ciudades medias a partir de la implantación del Tren de Alta Velocidad para mostrar cuáles son los factores diferenciales del desarrollo local en este fenómeno urbano
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The electrochemical behaviour of zinc has been extensively studied in alkaline and acid media, but only a few studies have been reported in neutral solutions, particularly in deaerated media. Zinc passivation in neutral medium and the effect of the ClO4- ion on the nucleation and growth of the passive layer is studied in this paper by a transient technique at different electrolyte concentrations and applied potentials. ZnO growth rate was shown to decrease with increasing electrolyte concentration. Moreover, passive layer growth occurred followed by pitting nucleation and growth. Film growth and pit nucleation are explained by means of the Macdonald and Engell-Stolica models.
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Volatiles produced by plantlets of Alpinia zerumbet were obtained by means of simultaneous distillation-extraction (SDE). The effects of indole-3-acetic acid, kinetin, thidiazuron and 6-benzylaminopurine on leaf and root volatile composition obtained by tissue cultures were investigated. A higher content of b-pinene and a lower content of sabinene were observed in leaf volatile of plantlets cultured in control, IAA and IAA+ TDZ media, as compared with those of donor plants. In vitro conditions were favorable to increase caryophyllene content. Volatile compounds from the root were characterized mainly by camphene, fenchyl-acetate and bornyl acetate; which constitute about 60% of total volatile.
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The objective of this Bachelor's Thesis is to find out the role of social media in the B-to-B marketing environment of the information technology industry and to discover how IT-firms utilize social media as a part of their customer reference marketing. To reach the objectives the concepts of customer reference marketing and social media are determined. Customer reference marketing can be characterized as one of the most practically relevant but academically relatively overlooked ways in which a company can leverage its customers and delivered solutions and use them as references in its marketing activities. We will cover which external and internal functions customer references have, that contribute to the growth and performance of B-to-B firms. We also address the three mechanisms of customer reference marketing which are 'status transfer', 'validation through testimonials' and 'demonstration of experience and prior performance'. The concept of social media stands for social interaction and creation of user-based content which exclusively occurs through Internet. The social media are excellent tools for networking because of the fast and easy access, easy interaction and vast amount of multimedia attributes. The allocation of social media is determined. The case company helps clarify the specific characteristics of social media usage as part of customer-reference-marketing activities. For IT-firms the best channels to utilize social media in their customer reference marketing activities are publishing and distribution services of content and networking services.
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Paratuberculosis is an important enteritis of ruminants caused by Mycobacterium avium subsp. paratuberculosis (Map). The disease is officially considered exotic in Brazil, but recent serological surveys and the isolation of the agent suggest it may occur in our herds. The aim of this study was to evaluate three different formulations of Herrold's egg yolk agar with mycobactin J (HEYM) and four faecal culture protocols considering their ability for Map growth as well as cost and ease of application. Three formulations of HEYM were inoculated with two suspensions of Map. Spiked faeces and naturally contaminated faecal samples were treated by the four faecal culture protocols. Centrifugation protocol and HEYM recommended by OIE showed the best results on the recovery of Map.
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The study aimed to quantify the concentrations of free IGF-I in serum and fluid of ovarian follicles in pre-pubertal gilts and describe the ovarian morphology by measuring the size of the ovaries and counting the number of surface follicles. Ovaries (n=1,000) from pre-pubertal gilts were obtained immediately after slaughter. A total of 10 samplings were performed, with ovaries obtained from 50 females for each collection. The follicles situated on the surface of each ovary were classified as small (SFs, 2 to 5mm in diameter) or large (LFs 6 to 10mm in diameter) and the follicular fluid was obtained by follicle aspiration. The collection of serum samples was performed after the gilts exsanguination using sterile tubes. From the pool of serum and follicular fluid obtained from 50 females, the concentration of free IGF-I was determined in each sample using an enzyme immunoassay kit (ELISA). The description of ovarian morphometry was performed in 100 ovaries from randomly selected gilts. The larger and smaller lengths of ovaries were measured, and the total number of SFs and LFs present on the surface of each ovary were also counted. The IGF-I concentration was greater (P<0.05) in LFs (170.92±88.29 ng/mL) compared with SFs (67.39±49.90ng/mL) and serum (73.48±34.63ng/mL). The largest and smallest length of the ovaries was 26.0±3.0 and 19.0mm ±2.0mm, respectively. The number of SFs (70.86±25.76) was greater (P<0.01) than LFs (6.54±5.26). The study concluded that LFs present greater levels of IGF-I when compared with SFs and blood, which is related to increased activity of the LFs and its differentiation to ovulation. In addition, ovaries of pre-pubertal gilts have a higher number of SFs compared to LFs. Therefore, our study demonstrated unique data regarding the physiological concentration of free IGF-I in ovarian follicles, that can be used in future research to evaluate the addition of this hormone in the in vitro production media of porcine embryos with the goal to improve the technique efficiency.
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Tässä väitöskirjassa tarkastellaan suomalaisen puoluejohtajuuden ja suuren puolueen johtajaksi nousun murroskautta 1980-luvun lopulta 2010-luvulle median ja politiikan vuorovaikutuksen näkökulmasta. Puolueiden johtaminen on myös Suomessa ollut miesten työtä, ja perinteisesti tehtävään on ollut yksi väylä: asettuminen ehdolle puheenjohtajavaalissa ja valituksi tulo puoluekokouksessa. Tarkastelujakson alkupuolella naisia oli Suomessa ensimmäistä kertaa ehdolla suurten puolueiden puheenjohtajavaaleissa. Kauden loppupuolella heitä myös valittiin tuohon tehtävään ja ensimmäiset naiset nousivat pääministeriksi. Tämä historiallinen murros päätti liki satavuotisen perinteen, jossa miehet ovat olleet Suomessa sekä suurten puolueiden että hallitustyön johtajia. Julkisessa keskustelussa kysymys tasa-arvosta jäi toissijaiseksi: naisia alettiin valita puoluejohtajiksi tilanteissa, joissa heidän valintansa nähtiin puolueille edulliseksi. Naisen valinta tulkittiin miehen valintaa merkittävämmäksi symboliseksi viestiksi, johon liitettiin ajatuksia uudistumisesta ja puolueen julkisuuskuvan parantamisesta. Merkille pantavaa on, että naisten ensimmäiset valinnat suurten puolueiden johtajiksi tapahtuivat vaiheessa, jossa puoluejohtajien valta-asema on vahvin kautta suomalaisen poliittisen historian. Tässä valossa näyttää siltä, että valta ei aina pakenekaan naisilta. Vaikka suomalainen yhteiskunta ja suomalaiset naiset ovat monessa mielessä olleet edelläkävijöitä tasa-arvon suhteen, politiikan johtopaikkoja tavoitelleet naiset ovat meilläkin kohdanneet kansainvälisessä tutkimuksessa naisten haasteeksi osoitettuja lasikattoja, pyöröovia ja liukkaita jyrkänteitä. Tutkittavan ajanjakson aikana konkretisoitui myös toinen mahdollinen, joskin poikkeuksellinen reitti suuren puolueen johtajaksi: pienen puolueen nouseminen suurten joukkoon eduskuntavaaleissa. Tämä vaihtoehto toteutui vuonna 2011 perussuomalaisten eduskuntavaalivoiton myötä. Perussuomalaisten nousu eduskunnan pienimmästä puolueesta kolmanneksi suurimmaksi mursi perinteisen kolmen suuren puolueen asetelman. Puolueen menestyksen seuraukset ovat olleet kauaskantoisemmat kuin ehkä ensin ajateltiin: perussuomalaisten vaalivoiton sosiaalidemokraateille, keskustalle, ja kokoomukselle aiheuttama järkytys heijastui myöhemmin myös niiden johtajavaihdoksiin ja -valintoihin. Sekä naisten läpimurrossa että populismin voittokulussa median rooli oli monisyisempi kuin siihen perinteisesti liitetty tiedon välittäjän ja valtaa pitävien toimia kriittisesti seuraavan neljännen valtiomahdin tehtävänkuva. Tutkittavalla jaksolla tiedotusvälineet tekivät onnistuneen intervention politiikan osapuoleksi. Toimittajat ottivat kantaa valintoihin ja ohjeistivat puolueita, ja puolueet taas mukauttivat näkyvyyden maksimoidakseen käytäntöjään median tarpeisiin. 1980-luvun lopulta 2010-luvulle ulottuvalla jaksolla suuren puolueen puoluejohtajaksi valikoitumisen kriteerit muuttuivat, samalla kun median merkitys johtajavalinnoissa ja myös puoluejohtajan käytännön työssä kasvoi. Mediasta tuli aiempaa konkreettisemmin johtajavalintojen ja valtakamppailun areena, ja siihen liittyvät näkökohdat nousivat myös keskeisiksi johtajan taitoja arvioitaessa. Kuka ehdokkaista toisi näkyvyyttä, ”pärjäisi” median paineissa ja vakuuttaisi äänestäjät? Vielä 1980- ja 1990-lukujen taitteessa johtajavalinnat olivat pitkälti puolueorganisaatioiden hallinnoimia prosesseja, joista lehdistö raportoi askeleen jäljessä kulkien. Viimeistään 2000-luvun ensimmäisellä vuosikymmenellä puolueet omaksuivat ajatuksen median hyödyllisyydestä. Tämän strategisen muutoksen myötä puolueet tulivat samalla luovuttaneeksi määriteltyvaltaa oman organisaationsa ulkopuolelle. Kokoomuksen vuoden 2014 johtajavaalissa silmiinpistävää oli pyrkimys sekä hyötyä julkisuudesta että palauttaa valtaa takaisin puolueelle. Politiikan mediajulkisuuden alttius tarttua myyviin poliitikkopersooniin, ilmiöihin, ristiriitoihin ja draamaan sekä vastaavasti populistijohtaja Timo Soinin ja perussuomalaisten kyky tarjota kaikkia näitä auttoivat puolueen suurvoittoon vuoden 2011 eduskuntavaaleissa. Organisaatioltaan pieni ja johtajaansa henkilöityvä puolue sai selvästi poliittista painoarvoaan suuremman julkisuuden, koska kiinnostavuus määritti näkyvyyden ja puolueen nousevasta kannatuksesta tuli yksi vaalien pääaiheista. Median ja politiikan suhteessa tapahtuneet muutokset olivat vauhdittamassa niin naisten nousua suurten puolueiden johtajiksi kuin populistisen johtajuuden läpimurtoa ja perussuomalaisten menestystä. Koska suurten puolueiden johtajista valikoituvat myös pääministerit, näiden muutosten vaikutus ulottuu Suomen poliittisesti vaikutusvaltaisimpaan tehtävään asti.
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Two attenuated bacillus Calmette-Guérin (BCG) preparations derived from the same Moreau strain, Copenhagen but grown in Sauton medium containing starch and bacto-peptone (onco BCG, O-BCG), or asparagine (intradermal BCG, ID-BCG), exhibited indistinguishable DNA sequences and bacterial morphology. The number of viable bacilli recovered from spleen, liver and lungs was approximately the same in mice inoculated with the vaccines and was similarly reduced (over 90%) in mice previously immunized with either BCG vaccine. The humoral immune response evoked by the vaccines was, however, distinct. Spleen cell proliferation accompanying the growth of bacilli in tissue was significantly higher in mice inoculated with O-BCG. These cells proliferated in vitro upon challenge with the corresponding BCG extract. Previous cell treatment with mAb anti-CD4 T cells abolished this effect. Anti-BCG antibodies, as assayed either in serum by ELISA or by determining the number of antibody-producing spleen cells by the spot-ELISA method, were significantly higher in mice inoculated with ID-BCG. Anti-BCG antibodies were detected in all immunoglobulin classes, but they were more prevalent in IgG with the following distribution among its isotypes: IgG1>(IgG2a = IgG2b)>IgG3. When some well-characterized Mycobacterium tuberculosis antigens were used as substitutes for BCG extracts in ELISA, although antibodies against the 65-kDa and 96-kDa proteins were detected significantly, antibodies against the 71-kDa, 38-kDa proteins and lipoarabinomannan were only barely detected or even absent. These results indicate that BCG bacilli cultured in Sauton-asparagine medium permitted the multiplication of bacilli, tending to induce a stronger humoral immune response as compared with bacilli grown in Sauton-starch/bacto-peptone-enriched medium.
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The objective of this study was to determine the effects of GDF-9, IGF-I, and GH alone or combined on preantral follicle survival, activation and development after 1 and 7 days of in vitro culture. Either fresh (non-cultured) or cultured ovarian tissue was processed for histological and fluorescence analysis. For all media tested, the percent of normal follicles was greater when compared to minimum essential medium supplemented (MEM+) alone, except when ovarian tissue was cultured with GDF-9/IGF-I or GDF-9/GH (P < 0.05). Fluorescence analysis showed that the percent of viable follicles after 7 days of culture was similar for non-cultured tissue and for all treatments tested. The percent of primordial follicles was reduced (P < 0.05) and there was a significant and concomitant increase in the percent of intermediate and primary follicles in all treatments tested after 7 days of culture when compared to non-cultured tissue. After 7 days of culture, the highest percent of intermediate follicles was observed with IGF-I/GH (61.3%), and the highest percent of primary follicles was achieved with IGF-I (57.7%). After 7 days of culture in MEM+ containing GDF-9, IGF-I and GH alone or in all associations, a significant increase in follicular diameter was observed when compared to MEM+ alone and non-cultured tissue. In conclusion, GDF-9, IGF-I and GH alone or in combination maintain preantral follicle survival and promote primordial follicle activation. Nevertheless, the data showed that IGF-I/GH and IGF-I alone are efficient in promoting the transition from primordial to intermediate follicles and from intermediate to primary follicles, respectively.
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Halotolerant or halophilic (Archaeabacteria) microorganisms can be found in salted and ripening fish products that are not affected by salt. They can be moderate or extremely halophilic bacteria. The extremely halophilic bacteria require between 15-30% of NaCl for growth. The extremely halophilic archaeobacteria may be selectively isolated in different media. The aim of this work was to determine the effectiveness of the Salt-Agar-Milk medium, a medium modified in our laboratory through the addition of MgSO4 and KCl - named SAMm, and its effect on the bacterial growth by means of comparison with other media, with and without milk, determining time of incubation and counting. Two samples of salted fish from local fish salting factories and two laboratory strains were used. The factory samples were matured anchovy and anchovy fillets in oil, and the laboratory strains were: Haloarcula spp. (proteolytic) and Halococcus spp. (non-proteolytic). The following media were alternatively used for the isolation of extremely halophilic bacteria: IRAM; Formulation of Gibbons and collaborators, Cod Milk agar, and SAMm. IRAM and Gibbons were also used enriched with milk. In the SAMm medium, there were obtained count values similar or higher than the ones of the traditional media; besides the simplicity of its elaboration, the possibility to obtain positive results two or three days earlier also added to its benefit. Consequently, it can be considered an alternative to the media traditionally used for the studied halophilic bacteria.
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Rampant increases in oil prices and detrimental effects of fossil fuels on the environment have been the main impetus for the development of environmentally friendly and sustainable energy sources. Amongst the many possibilities, microalgae have been proposed as a new alternative energy source to fossil fuels, as their growth is both sustainable and ecologically safe. By definition, microalgae are unicellular photosynthetic microorganisms containing chlorophyll a. These organisms are capable of producing large quantities of oils, surpassing that of traditional oil-seed crops, which can be transformed, through chemical processes, into biofuels such as biodiesel or bio-gasoline. Thus, recent research has gone into discovering high lipid producing algal strains, optimising growth media for increased lipid production and developing metabolic engineering to make microalgae a source of biofuel that is competitive to more traditional sources of biofuel and even to fossil fuel. In this context, the research reported here focused on using a mixotrophic growth mode as a way to increase lipid production for certain strains of microalgae. In addition, nitrogen starvation combined with mixotrophy was studied to analyse its effects on lipid production. Mixotrophy is the parallel usage of two trophic modes, in our case photoautotrophy and heterotrophy. Consequently, 12 algal strains were screened for mixotrophic growth, using glycerol as a carbon source. Glycerol is a waste product of the current biodiesel industry; it is a cheap and abundant carbon source present in many metabolic pathways. From this initial screening, several strains were chosen for subsequent experiments involving nitrogen starvation. Nitrogen starvation has been shown to induce lipid accumulation. The results obtained show that a mixotrophic growth mode, using glycerol as a carbon source, enhances lipid production for certain strains. Moreover, lipid enhancement was shown for nitrogen starvation combined with mixotrophic growth mode. This was dependant on time spent under nitrogen starvation and on initial concentrations of the nitrogen source.