Guava fruit loss caused by rust

The aim of this paper was to estimate the loss caused by rust (Puccinia psidii) to 'Paluma' guava production in orchards located in Rio de Janeiro State. The disease intensity on the reproductive organs of plants was observed during two chemical control experiments carried out in 2003 and 2004. The loss was estimated based on simple linear regression and the production reduction (fruit number and weight ha-1) on the incidence of diseased buds and fruits. In the first experiment, no relationship was established between incidence of diseased buds and loss since there was a delay in spraying and the incidence of buds showing rust was high (mean of 47%) at the beginning of flowering. In the second experiment (2003-2004), spraying occurred at the beginning of the epidemics and there was a linear relationship between incidence of diseased buds and loss, justifying fungicide intervention at this stage. For the fruiting stage, a significant relationship was found between incidence of diseased fruits and loss in both experiments. In the absence of chemical control, rust reduced fruit production by around 90%.

Problems and potentialities of e-Learning for regular undergraduate courses in emergency medicine

BACKGROUND: E-learning techniques are spreading at great speed in medicine, raising concerns about the impact of adopting them. Websites especially designed to host courses are becoming more common. There is a lack of evidence that these systems could enhance student knowledge acquisition. GOAL: To evaluate the impact of using dedicated-website tools over cognition of medical students exposed to a first-aid course. METHODS: Prospective study of 184 medical students exposed to a twenty-hour first-aid course. We generated a dedicated-website with several sections (lectures, additional reading material, video and multiple choice exercises). We constructed variables expressing the student's access to each section. The evaluation was composed of fifty multiple-choice tests, based on clinical problems. We used multiple linear regression to adjust for potential confounders. RESULTS: There was no association of website intensity of exposure and the outcome - beta-coeficient 0.27 (95%CI - 0.454 - 1.004). These findings were not altered after adjustment for potential confounders - 0.165 (95%CI -0.628 - 0.960). CONCLUSION: A dedicated website with passive and active capabilities for aiding in person learning had not shown association with a better outcome.

Osingonjakopolitiikan määräytyminen ja sen osakekurssivaikutukset Helsingin pörssissä

Tämän työn tarkoituksena oli tutkia lineaarisen regressioanalyysin avulla sekä osingonjakopolitiikan määräytymiseen vaikuttavia tekijöitä että osinkojen osakekurssivaikutusta Helsingin pörssissä. Osinkopolitiikan määräytymistä tutkittiin yhtiön koon, kannattavuuden, velkaisuuden, investointi- ja kasvumahdollisuuksien sekä sisäpiirin omistuksen avulla. Käytetty aineisto koostuu Helsingin pörssissä noteerattujen yhtiöiden tilinpäätösluvuista ja osakekurssitiedoista vuosina 2000-2010. Empiiriset tutkimukset osoittivat, että osinkotuottoon vaikuttavia tekijöitä Helsingin pörssissä ovat yhtiön kannattavuus, velkaisuus, investointi- ja kasvumahdollisuudet sekä sisäpiirin omistus. Saadut tulokset ovat samansuuntaisia aikaisempien tutkimusten kanssa. Toinen merkittävä löydös on, että osingoilla todettiin olevan positiivinen yhteys osakekurssimuutoksiin Helsingin pörssissä. Osinkojen ja osakekurssin välinen yhteys tukee signalointiteoriaa.

Asuntosijoittaminen: demografisten ja taloudellisten muuttujien vaikutus asuntojen hinta- ja vuokrakehitykseen Suomessa

Tutkielman tavoitteena on tehdä katsaus asuntosijoittamiseen sekä löytää asuntosijoittajalle tärkeää tietoa asuntojen hinta- ja vuokrakehitykseen vaikuttavista alueellisista tekijöistä. Asuntojen hintoihin vaikuttavia tekijöitä tutkitaan sekä kasvukaupungeissa että rakennemuutosalueilla. Asuntojen vuokrakehitykseen vaikuttavia selittäviä tekijöitä tutkitaan koko Suomen, pääkaupunkiseudun ja muun Suomen alueilla. Tutkimus toteutetaan käyttäen lineaarista regressioanalyysiä ja käytettävä aineisto koostuu muuttujien aikasarjoista vuosilta 1988–2010 sekä 1996–2009. Saatujen tulosten perusteella nettokansantulolla ja asuntokunnan käytet-tävissä olevalla rahatulolla on selkeä vaikutus asuntojen hintakehitykseen kasvukeskuksissa. Rakennemuutosalueilla työllisyyden ja teollisuuden vaikutukset ovat vahvoja. Asuntojen vuokriin vaikuttavista tekijöistä mm. asuinkerrostalokannalla, aloittaneiden yritysten määrällä ja asuntokunnan käytettävissä olevalla rahatulolla voidaan nähdä olevan selkeä vaikutus neliövuokran kehitykseen.

Spatio-temporal modelling of the duration of the cotton cycle in the State Of Goiás, Brazil

The objective of this work was to develop and validate a mathematical model to estimate the duration of cotton (Gossypium hirsutum L. r. latifolium hutch) cycle in the State of Goiás, Brazil, by applying the method of growing degree-days (GD), and considering, simultaneously, its time-space variation. The model was developed as a linear combination of elevation, latitude, longitude, and Fourier series of time variation. The model parameters were adjusted by using multiple-linear regression to the observed GD accumulated with air temperature in the range of 15°C to 40°C. The minimum and maximum temperature records used to calculate the GD were obtained from 21 meteorological stations, considering data varying from 8 to 20 years of observation. The coefficient of determination, resulting from the comparison between the estimated and calculated GD along the year was 0.84. Model validation was done by comparing estimated and measured crop cycle in the period from cotton germination to the stage when 90 percent of bolls were opened in commercial crop fields. Comparative results showed that the model performed very well, as indicated by the Pearson correlation coefficient of 0.90 and Willmott agreement index of 0.94, resulting in a performance index of 0.85.

Determination of the influence of the variation of reducing and non-reducing sugars on coffee quality with use of artificial neural network

The present study aimed at evaluating the use of Artificial Neural Network to correlate the values resulting from chemical analyses of samples of coffee with the values of their sensory analyses. The coffee samples used were from the Coffea arabica L., cultivars Acaiá do Cerrado, Topázio, Acaiá 474-19 and Bourbon, collected in the southern region of the state of Minas Gerais. The chemical analyses were carried out for reducing and non-reducing sugars. The quality of the beverage was evaluated by sensory analysis. The Artificial Neural Network method used values from chemical analyses as input variables and values from sensory analysis as output values. The multiple linear regression of sensory analysis values, according to the values from chemical analyses, presented a determination coefficient of 0.3106, while the Artificial Neural Network achieved a level of 80.00% of success in the classification of values from the sensory analysis.

Evaluation of empirical methods to estimate reference evapotranspiration in Uberaba, State of Minas Gerais, Brazil

Evapotranspiration is the process of water loss of vegetated soil due to evaporation and transpiration, and it may be estimated by various empirical methods. This study had the objective to carry out the evaluation of the performance of the following methods: Blaney-Criddle, Jensen-Haise, Linacre, Solar Radiation, Hargreaves-Samani, Makkink, Thornthwaite, Camargo, Priestley-Taylor and Original Penman in the estimation of the potential evapotranspiration when compared to the Penman-Monteith standard method (FAO56) to the climatic conditions of Uberaba, state of Minas Gerais, Brazil. A set of 21 years monthly data (1990 to 2010) was used, working with the climatic elements: temperature, relative humidity, wind speed and insolation. The empirical methods to estimate reference evapotranspiration were compared with the standard method using linear regression, simple statistical analysis, Willmott agreement index (d) and performance index (c). The methods Makkink and Camargo showed the best performance, with "c" values ​​of 0.75 and 0.66, respectively. The Hargreaves-Samani method presented a better linear relation with the standard method, with a correlation coefficient (r) of 0.88.

Validation study of an overall radiation balance estimation method under Ponta Grossa (PR) Brazil weather conditions

Radiation balance is the fraction of incident solar radiation upon earth surface which is available to be used in several natural processes, such as biological metabolism, water loss by vegetated surfaces, variation of temperature in farming systems and organic decomposition. The present study aimed to assess and validate the performance of two estimation models for Rn in Ponta Grossa city, Paraná State, Brazil. To this end, during the period of 04/01/2008 to 04/30/2011, from radiometric data collected by an automatic weather station set at the Experimental Station, of the State University of Ponta Grossa. We performed a linear regression study by confrontation between measurements made through radiometric balance and Rn estimates obtained from Brunt classical method, and the proposed method. Both models showed excellent performance and were confirmed by the statistical parameters applied. However, the alternative method has the advantage of requiring only global solar radiation values, temperature, and relative humidity.

The use of ALOS/PALSAR data for estimating sugarcane productivity

Some models have been developed using agrometeorological and remote sensing data to estimate agriculture production. However, it is expected that the use of SAR images can improve their performance. The main objective of this study was to estimate the sugarcane production using a multiple linear regression model which considers agronomic data and ALOS/PALSAR images obtained from 2007/08, 2008/09 and 2009/10 cropping seasons. The performance of models was evaluated by coefficient of determination, t-test, Willmott agreement index (d), random error and standard error. The model was able to explain 79%, 12% and 74% of the variation in the observed productions of the 2007/08, 2008/09 and 2009/10 cropping seasons, respectively. Performance of the model for the 2008/09 cropping season was poor because of the occurrence of a long period of drought in that season. When the three seasons were considered all together, the model explained 66% of the variation. Results showed that SAR-based yield prediction models can contribute and assist sugar mill technicians to improve such estimates.

Software for design of experiments and response modelling of cake ltration applications

Filtration is a widely used unit operation in chemical engineering. The huge variation in the properties of materials to be ltered makes the study of ltration a challenging task. One of the objectives of this thesis was to show that conventional ltration theories are di cult to use when the system to be modelled contains all of the stages and features that are present in a complete solid/liquid separation process. Furthermore, most of the ltration theories require experimental work to be performed in order to obtain critical parameters required by the theoretical models. Creating a good overall understanding of how the variables a ect the nal product in ltration is somewhat impossible on a purely theoretical basis. The complexity of solid/liquid separation processes require experimental work and when tests are needed, it is advisable to use experimental design techniques so that the goals can be achieved. The statistical design of experiments provides the necessary tools for recognising the e ects of variables. It also helps to perform experimental work more economically. Design of experiments is a prerequisite for creating empirical models that can describe how the measured response is related to the changes in the values of the variable. A software package was developed that provides a ltration practitioner with experimental designs and calculates the parameters for linear regression models, along with the graphical representation of the responses. The developed software consists of two software modules. These modules are LTDoE and LTRead. The LTDoE module is used to create experimental designs for di erent lter types. The lter types considered in the software are automatic vertical pressure lter, double-sided vertical pressure lter, horizontal membrane lter press, vacuum belt lter and ceramic capillary action disc lter. It is also possible to create experimental designs for those cases where the variables are totally user de ned, say for a customized ltration cycle or di erent piece of equipment. The LTRead-module is used to read the experimental data gathered from the experiments, to analyse the data and to create models for each of the measured responses. Introducing the structure of the software more in detail and showing some of the practical applications is the main part of this thesis. This approach to the study of cake ltration processes, as presented in this thesis, has been shown to have good practical value when making ltration tests.

The effect of dynamic capabilities on operational-level innovation – Empirical study in magazine publishing industry

This master’s thesis aims to examine the relationship between dynamic capabilities and operational-level innovations. In addition, measures for the concept of dynamic capabilities are developed. The study was executed in the magazine publishing industry which is considered favourable for examining dynamic capabilities, since the sector is characterized by rapid change. As a basis for the study and the measure development, a literary review was conducted. Data for the empirical section was gathered by a survey targeted to chief-editors of Finnish consumer magazines. The relationship between dynamic capabilities and innovation was examined by multiple linear regression. The results indicate that dynamic capabilities have effect on the emergence of radical innovations. Environmental dynamism’s effect on radical innovations was not detected. Also, dynamic capabilities’ effect on innovation was not greater in turbulent operating environment.

IFRS 2 Osakeperusteiset maksut – ylimmän johdon osakeperusteisen palkitsemisjärjestelmien käyttöä selittävät tekijät

Työn tarkoituksena on selvittää, mitkä tekijät vaikuttavat IFRS 2 - standardin mukaisen osakeperusteisen palkitsemisen käyttöön ja sen yleisyyteen sekä mitkä tekijät selittävät IFRS 2 -standardin mukaisen osakeperusteisen palkitsemisen osuutta koko henkilöstökuluista tutkimuksessa esiintyvissä OMX-Nordic pörssin listatuissa Suomen ja Ruotsin large cap - yrityksissä. Työn empiirinen tutkimus toteutetaan laadullisella tutkimuksella, jossa lisäksi käytetään hyväksi regressioanalyysin tuloksia vahvistamaan tutkimuksessa muodostettuja ennakko-oletuksia. Tutkimuksesta kävi ilmi, että IFRS 2 -standardin mukaisen osakeperusteisen palkitsemisen käyttöä selittävät toimitusjohtajan ikä, yrityksen koko sekä yrityksen tutkimus- ja kehitystoiminta. Osakeperusteisen palkitsemisen osuutta yrityksen koko henkilöstökuluista puolestaan selittävät yrityksen velkaantuneisuus, palkitsemistapa sekä toimialan riskisyys.

Software for design of experiments and response modelling of cake filtration applications

Filtration is a widely used unit operation in chemical engineering. The huge variation in the properties of materials to be ltered makes the study of ltration a challenging task. One of the objectives of this thesis was to show that conventional ltration theories are di cult to use when the system to be modelled contains all of the stages and features that are present in a complete solid/liquid separation process. Furthermore, most of the ltration theories require experimental work to be performed in order to obtain critical parameters required by the theoretical models. Creating a good overall understanding of how the variables a ect the nal product in ltration is somewhat impossible on a purely theoretical basis. The complexity of solid/liquid separation processes require experimental work and when tests are needed, it is advisable to use experimental design techniques so that the goals can be achieved. The statistical design of experiments provides the necessary tools for recognising the e ects of variables. It also helps to perform experimental work more economically. Design of experiments is a prerequisite for creating empirical models that can describe how the measured response is related to the changes in the values of the variable. A software package was developed that provides a ltration practitioner with experimental designs and calculates the parameters for linear regression models, along with the graphical representation of the responses. The developed software consists of two software modules. These modules are LTDoE and LTRead. The LTDoE module is used to create experimental designs for di erent lter types. The lter types considered in the software are automatic vertical pressure lter, double-sided vertical pressure lter, horizontal membrane lter press, vacuum belt lter and ceramic capillary action disc lter. It is also possible to create experimental designs for those cases where the variables are totally user de ned, say for a customized ltration cycle or di erent piece of equipment. The LTRead-module is used to read the experimental data gathered from the experiments, to analyse the data and to create models for each of the measured responses. Introducing the structure of the software more in detail and showing some of the practical applications is the main part of this thesis. This approach to the study of cake ltration processes, as presented in this thesis, has been shown to have good practical value when making ltration tests.

Esimiestyön vaikutus työhön sitoutumiseen ja työhyvinvointiin

Tutkielman kohteena on tarkastella suhteita esimiestyön, työhön sitoutumisen ja työhyvinvoinnin välillä ICT – alalla Suomessa tapaustutkimuksena. Ilmiöiden välisiä suhteita testattiin sähköisellä henkilöstön sitoutumista mittaavalla kyselylomakkeella vuosina 2011 ja 2012. Yhteensä näinä vuosina kyselyyn vastasi 538 henkilöä, joista tutkittava otos on muodostunut. Lineaarisella regressioanalyysillä osoitettiin merkittäviä tilastollisia korrelaatioita esimiestyön ja työhön sitoutumisen sekä työhön sitoutumisen ja työhyvinvoinnin välillä.

Luottamuksen vaikutus tiedon jakamiseen ja yhteistyöhön

Tutkielman tarkoituksena oli tutkia teoreettisesti ja empiirisesti luottamuksen vaikutusta organisaatioyksiköiden väliseen tiedon jakamiseen ja yhteistyöhön. Luottamuksen näkökulmasta tarkasteltiin henkilöityvän ja ei-henkilöityvän luottamuksen vaikutusta yhdessä ja erikseen. Tiedon jakamisessa tarkasteltiin hiljaisen sekä käsitteellisen tiedon jakamista. Luottamuksen vaikutusta tiedon jakamiseen on yleisesti tutkittu, mutta tutkielman tavoitteena oli tutkia ilmiötä pankki- ja vakuutusliiketoimintaa harjoittavan kohdeorganisaation näkökulmasta. Tutkimustulokset analysoitiin kvantitatiivisilla tutkimusmenetelmillä, joista mukana oli faktorianalyysi ja lineaarinen regressio. Tämän tutkimuksen perusteella luottamuksella oli positiivinen vaikutus tiedon jakamiseen. Henkilöityvän luottamuksen vaikutus oli merkittävästi voimakkaampi kuin ei-henkilöityvän luottamuksen. Luottamuksen vaikutus yhteistyöhön oli myös positiivinen, jossa henkilöityvän ja ei-henkilöityvän luottamuksen vaikutus ja voimakkuus olivat yhtäläisiä.