986 resultados para semi empirical calculations


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This paper reports on the identification of volatile and semi-volatile compounds and a comparison of the chromatographic profiles obtained by Headspace Solid-Phase Microextraction/Gas Chromatography with Mass Spectrometry detection (HS-SPME-GC-MS) of dried leaves of Mikania glomerata Sprengel (Asteraceae), also known as 'guaco.' Three different types of commercial SPME fibers were tested: polydimethylsiloxane (PDMS), polydimethylsiloxane/divinylbenzene (PDMS/DVB) and polyacrylate (PA). Fifty-nine compounds were fully identified by HS-SPME-HRGC-MS, including coumarin, a marker for the quality control of guaco-based phytomedicines; most of the other identified compounds were mono- and sesquiterpenes. PA fibers performed better in the analysis of coumarin, while PDMS-DVB proved to be the best choice for a general and non-selective analysis of volatile and semi-volatile guaco-based compounds. The SPME method is faster and requires a smaller sample than conventional hydrodistillation of essential oils, providing a general overview of the volatile and semi-volatile compounds of M. glomerata.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tässä pro gradu -tutkielmassa tarkastellaan henkilöstöresurssien organisointia suuren alusöljyvahingon torjuntatilanteessa. Tavoitteena on suunnitella Suomenlahden rannikon öljyntorjunnasta vastaavien viranomaisten käyttöön optimaalinen rekrytointistrategia pahimman todennäköisen alusöljyvahingon varalle. Tutkimuksessa selvitetään myös millainen työsopimus öljyntorjuntatyöntekijöiden kanssa voidaan sopia. Näiden lisäksi etsitään vastausta siihen,kuinka työvoima saadaan pidettyä. Tämän laadullisen tutkimuksen teoreettinen osuus toteutettiin kirjallisuuskatsauksena. Tutkimuksen empiirinen aineisto kerättiin haastattelemalla yhdeksää asiantuntijaa syksyn 2009 aikana. Haastattelut olivat muodoltaan puolistrukturoituja teemahaastatteluja. Tutkimustulosten mukaan merkittävin lisätyövoiman tarve ilmenee käsin tehtävässä rantapuhdistustyössä. Etenkin puhdistustyön pitkittyessä pelastusviranomaiset tarvitsevat avukseen ulkopuolista työvoimaa. Rekrytointi suoritetaan muutamien viikkojen kuluessa öljyvahingon aiheutumisen jälkeen. Alueellinen pelastuslaitos suorittaa rekrytoinnin käyttäen tehokkaita, laajan kohderyhmän tavoittavia rekrytointiviestinnän välineitä (esim. sanomalehdet, TV ja Internet). Työntekijöiden kanssa sovitaan määräaikainen, Kunnallista virkaja työehtosopimusta noudattava työsopimus. Tärkeimpinä puhdistustyöntekijöitä motivoivina tekijöinä nähdään työn merkitys yhteiskunnalle, selkeästi määritelty, saavutettavissa oleva tavoite sekä palaute tehdystä työstä.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work was aimed at evaluating the possibility of using bromophenol blue as an indicator for detecting the presence of Sclerotinia sclerotiorum in the seeds of dry-beans (Phaseolus vulgaris) and soybean (Glycine max), through incubation of the seeds on an agar medium and "blotter" substrates. The seeds were artificially inoculated with four S. sclerotiorum isolates, plated on the agar medium, named Neon, and on modified Neon agar media all incubated at 14 and 20 ºC for seven days in the dark. Half of the seeds inoculated were surface desinfested prior to plating on the medium. The seeds showing change of colour in the medium, from blue to light yellow, as well as formation of typical mycelium and sclerotia in some cases, were considered to be infected or contaminated by S. sclerotiorum. The two incubation temperatures compared did not show significant (P<0.05) differences in detection level for most of the isolates tested on the different media. According to results obtained in this study, the Neon agar medium with incubation at 14 or 20 ºC has proved to be a reliable and quick method for the detection of S. sclerotiorum mycelium in naturally infected seeds of bean and soybean.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tämän diplomityön tavoitteena oli tutustua ohutlevyjen nykyaikaisiin koneellisiin leikkausmenetelmiin ja tutkia niiden soveltuvuutta yrityksen tarpeisiin. Kohdeyrityksessä investoinnin tarve jakautui tuottavuusinvestoinnin, korvausinvestoinnin ja strategisen investoinnin kesken. Tavoitteena oli luoda investointipolku, jonka avulla poissuljettiin menetelmät, jotka eivät soveltuneet yrityksen tuotantoon. Työn kirjallisuusosuudessa tarkastellaan teoriatietoja, jotka liittyvät yleisesti nykyaikaisiin ohutlevyjen leikkausmenetelmiin sekä investointiprojektin suunnitteluun ja toteutuksen teoriaan. Lisäksi käsitellään investointeihin liittyviä kannattavuus- ja kustannuslaskennan perusperiaatteita. Työn empiirisessä osassa selvitettiin yrityksen ohutlevyosien valmistuksen periaatteita nykytila-analyysin avulla. Tämän perusteella määritettiin nykyaikaisista markkinoilla olevista menetelmistä yritykselle soveltuvin. Tutkimuksen perusteella laserleikkaus oli menetelmistä soveltuvin. Perusinvestoinniltaan laser oli vaihtoehtoisista menetelmistä kallein, mutta se soveltui käytettävyyden, tehokkuuden, joustavuuden ja muiden ominaisuuksiensa perusteella parhaiten tuotannon tarpeisiin. Työn merkittävimmät tulokset osoittivat, että investoinnin kannattavuus riippui koneelle saatavasta käyttösuhteesta. Uusien koneiden tehokkuus lyhentäisi tuotannon läpimenoaikoja, mutta ilman riittävää kapasiteetin käyttöastetta kappaleiden omakustannusarvo nousisi. Lopputulokset ja suositukset on esitetty työn lopussa.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

O vírus da meleira, transmitido por Bemisia tabaci, é um dos maiores problemas da cultura do mamoeiro (Carica papaya), sendo responsável por perdas de até 100% na produção. Com o objetivo de compreender melhor sua epidemiologia e gerar subsídios para estudos da influência de fatores culturais e bioecológicos na dinâmica da doença, avaliou-se a distribuição espacial de plantas afetadas pela meleira em zonas de Trópico Úmido e Trópico Semi-árido, em 15 plantios comerciais em Eunápolis-BA e Petrolina-PE, entre jan. 2000 e mar. 2001. As áreas foram mapeadas anotando-se a posição de cada planta e a presença ou ausência de sintomas. Foram consideradas doentes aquelas que apresentavam frutos com exsudação espontânea do látex, látex muito fluido, frutos borrados e/ou folhas do ápice com o bordo necrosado. Pelas análises de seqüências ordinárias, índice de dispersão, áreas isópatas e ajuste dos logaritmos das variâncias binomial e de acordo com a lei de Taylor, observaram-se maior agregação nas linhas de plantio que entre linhas e uma agregação de mediana a forte em sub-áreas (1,4 < ID < 3,1). Na maioria dos lotes, as áreas de maior incidência concentraram-se nas bordas dos talhões, o que indica que a migração de vetores assume um papel importante na disseminação da doença. Em alguns casos foi possível detectar a presença de focos isolados no interior dos lotes, o que sugere a formação de colônias dos vetores e transmissão planta a planta a partir de inóculo secundário. Não foram observadas diferenças significativas na distribuição espacial de plantas doentes entre as áreas das duas regiões.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A semi-selective agar medium was developed for detection of Xanthomonas axonopodis pv. malvacearum (Xam) in cotton (Gossypium hirsutum) seed. The basic medium was peptone-sucrose-agar (PSA). Criteria for the semi-selective medium were the typical colony characters of Xam and its pathogenicity on cotton. Several systemic fungicides and antibiotics in different concentrations were tested alone or in combination with others. The final composition of the semi-selective agar medium was established after several attempts in order to inhibit most of the fungal and bacterial saprophytes and favour the development of Xam. It contained PSA + cyclohexamide, cephalexin, pencycuron, triadimenol and tolylfluanid. The bacteria were recovered from naturally infected seeds by the direct plating of 2,000 surface disinfected seeds on the semi-selective medium. The recovery of the pathogen from naturally infected leaf tissues and in dilution plating, on semi-selective medium and on nutrient agar, were comparable. Among the three detection methods tested, the semi-selective medium was found to be the most reliable and quantifiable. Degree of severity of angular leaf spot in the field was not always correlated with the level of infection in the seed. This is the first report of a semi-selective agar medium to detect the presence of Xam in naturally infected cotton seed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Para a detecção de Xanthomonas axonopodis pv. phaseoli (Xap) em extratos de sementes inteiras e moídas de feijão, naturalmente contaminadas e sadias foram utilizados os meio de cultura semi-seletivos XCP1 e MT e o não seletivo 523 de Kado & Hesket. Os extratos de sementes foram também inoculados em folhas primárias de feijoeiro. O meio de cultura semi-seletivo XCP1 foi o mais eficiente na quantificação e detecção de Xap em extratos de sementes inteiras de feijão. Os extratos de sementes contaminadas, inoculados nas folhas primárias de feijoeiro produziram sintomas do crestamento bacteriano comum.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The main purpose of this study was to analyze how stress tests are used in risk management in the Finnish banking and insurance sectors. In order to enhance understanding of the topic, stress testing was explored in the context of corporate governance and regulato-ry implications of Basel II and Solvency II on stress testing were examined. In addition, the effects of the global financial crisis on stress testing were mapped and the differences in stress testing practices between the banking and insurance sector were discussed. The research method was qualitative case study and it was conducted by interviewing risk managers from ten institutions and a representative from FIN-FSA. Findings pointed out that stress testing practices vary significantly between different institutions. Interesting observations were made in terms of stress testing practices in the banking and insurance sectors. The increasing importance and use of stress tests were recognized as a result of the financial crisis. Stress testing was even considered more like art than science given the amount of challenges it involves. In general, improvements in stress tests were suggested, with an emphasis on stress concentration between different types of risks.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The objective of this case study is to provide a Finnish solution provider company an objective, in-depth analysis of their project based business and especially of project estimation accuracy. A project and customer profitability analysis is conducted as a complementary addition to describe profitability of the Case Company’s core division. The theoretical framework is constructed on project profitability and customer profitability analysis. Project profitability is approached starting from managing projects, continuing to project pricing process and concluding to project success. The empirical part of this study describes the Case Company’s project portfolio, and by means of quantitative analysis, the study describes how the characteristics of a project impact the project’s profitability. The findings indicate that it really makes a difference in project portfolio’s estimated and actual profitability when methods of installation and technical specifications are scrutinized. Implications on profitability are gathered into a risk assessment tool proposal.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

E-Lychnophoric acid 1, its derivative ester 2 and alcohol 3 killed 100% of trypomastigote blood forms of Trypanosoma cruzi at the concentrations of 13.86, 5.68, and 6.48 µg/mL, respectively. Conformational distribution calculations (AM1) of 1, 2 and 3 gave minimum energies for the conformers a, b, c, and d, which differ from each other only in the cyclononene ring geometry. Calculations (DFT/BLYP/6-31G*) of geometry optimization and chemical properties were performed for conformers of 1, 2, and 3. The theoretical results were numerically compared to the trypanocidal activity. Calculated values of atomic charge, orbital population, and vibrational frequencies showed that the C-4-C-5 pi-endocyclic bond does not affect the trypanocidal activity of the studied compounds. Nevertheless, the structure of the group at C-4 strongly influences the activity. However, the theoretical results indicated that the intra-ring (C-1 and C-9) and pi-exocycle (C-8 and C-14) carbons of caryophyllene-type structures promote the trypanocidal activity of these compounds.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tässä tutkimuksessa tutkittiin aineettoman pääoman merkitystä alkavan yrityksen rahoituksen saantiin. Tutkimuksen teoreettinen osuus toteutettiin kirjallisuuskatsauksena. Tutkimuksen empiirinen osuus toteutettiin laadullisena tutkimuksena. Tutkimusaineisto kerättiin puolistrukturoiduilla yksilöllisillä teemahaastatteluilla alkavan yrityksen ensisijaisilta rahoittajilta, joita katsottiin olevan Elinkeino-, liikenne- ja ympäristökeskus, Teknologian kehittämiskeskus Tekes, Keksintösäätiö, Finnvera Oyj ja pankit. Tutkimuksen tuloksena selvisi, että aineettomalla pääomalla on tärkeä merkitys alkavan yrityksen rahoituksen saantiin. Mikäli alkavalla yrittäjällä ei ollut aineetonta pääomaa, alkava yritys ei saanut rahoitusta vaikka vakuudet olisivat olleet kunnossa. Tämän johdosta, nyt tulisi valita mittarit, joilla pystytään mittaamaan rahoituksen kannalta vaikuttavat aineettoman pääoman menestystekijät ja raportoimaan nämä. Jotta yritykset olisivat rahoittajan kannalta vertailukelpoisia, tulisi rahoittajan määritellä mittarit, joihin se rahoitusta myöntäessään kiinnittää huomiota.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The main purpose of this study is to examine whether accounting-based variables can be used to measure systematic risk of a company using Finnish data. When the fundamental sources of systematic risk are known, companies are able to manage these risks and increase company value. Accounting beta was formed based on OLS regression models. Theoretical background for the study was based on the findings of studies according to which business risk, financial risk, operating risk and growth risk can be theoretically regarded as determinants of the systematic risk. The results reveal that accounting variables describe systematic risk of a company. The accounting beta is found to be particularly sensitive to the changes in the risk components. The investigation is confidential until 15.10.2012.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Tässä diplomityössä on tutkittu epävarmuuden mallintamista investointilaskelmissa. Kirjallisuuden perusteella luotiin prosessimalli, jolla voidaan strukturoidusti tehdä yritysinvestointi- tai yritysirtaantumispäätös. Malli koostuu neljästä päävaiheesta, mutta pääpainopiste mallissa on laskentamenetelmissä. Luotua prosessimallia sekä erityisesti laskentamenetelmiä on sovellettu yritysesimerkin avulla. Epävarmuuden mallintamisongelmaa on käsitelty sekä perinteisten klassillisten investointiteorioiden että reaalioptioajatteluun pohjautuvien menetelmien avulla. Reaalioptioteoriaan perustuvien menetelmien avulla voidaan ottaa huomioon tulevat epävarmuudet ja päätöksentekomahdollisuudet. Perinteisten reaalioptioteorioiden käytännön elämän vastaisten taustaoletuksien vuoksi tutkittiin erityisesti uusimpia malleja. Diplomityössä yritysesimerkiksi valittiin Paroc Group, jonka yritysjärjestelytilannetta tutkittiin sen nykyisen omistajan eli pankin näkökulmasta. Diplomityön yhtenä keskeisenä tavoitteena oli selvittää, että kannattaako pankin myydä yhtiö tämän hetkisellä markkinahinnalla vai odottaa parempaa myyntiajankohtaa.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

A murcha-de-curtobacterium, causada pela bactéria Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff), é um importante problema para o cultivo de feijão (Phaseolus vulgaris L.) na região Centro-Sul do Brasil. A principal forma de disseminação da bactéria é por sementes contaminadas. Embora a ocorrência desta doença seja relativamente recente no Brasil, Cff tem sido disseminado rapidamente nas regiões produtoras de feijão do país. Este trabalho teve como objetivo ajustar o meio de cultura CNS (Corynebacterium Nebraskense Selective Medium) para recuperação e detecção de Cff em solo e sementes de feijoeiro. Suspensões provenientes da lavagem de amostras de solo e sementes contaminadas pela bactéria foram plaqueadas no meio de cultura CNS - modificado. Os ajustes realizados no meio de cultura possibilitaram a recuperação eficiente de Cff presente em solo e sementes contaminadas. As modificações estabelecidas para o meio CNS foram a redução da concentração de sulfato de polimixina para 16 mg/l, exclusão do componente ciclohexamida e substituição do fungicida Daconil 2787-F (530 mg/ml de chlorothalonil) pelo Dacostar 500 (500 mg/ml de chlorothalonil).