Production and partial characterization of lipase from Penicillium verrucosum obtained by submerged fermentation of conventional and industrial media

The growing interest in lipase production is related to the potential biotechnological applications that these enzymes present. Current studies on lipase production by submerged fermentation involve the use of agro-industrial residues aiming at increasing economic attractiveness. Based on these aspects, the objective of this work was to investigate lipase production by Penicillium verrucosum in submerged fermentation using a conventional medium based on peptone, yeast extract, NaCl and olive oil, and an industrial medium based on corn steep liquor, Prodex Lac (yeast hydrolysate), NaCl and olive oil, as well as to characterize the crude enzymatic extracts obtained. Kinetics of lipase production was evaluated and the highest enzymatic activities, of 3.15 and 2.22 U.mL-1, were observed when conventional and industrial media were used, respectively. The enzymatic extract showed optimal activity in the range from 30 to 40 °C and at pH 7.0. Although the industrial medium presents economical advantages over the conventional medium, the presence of agro-industrial residues rich in nitrogen and other important nutrients seemed to contribute to a reduction in lipase activity.

Esimiesten muuttuvat osaamistarpeet media- ja kustannusalan murroksessa

Organisaatioiden toimintaympäristö on muuttunut ratkaisevasti ja muutos jatkuu. Muutok-sen kiihtyvä nopeus, asioiden epävarmuus ja kompleksisuus aiheuttavat uudenlaisia haas-teita työelämälle, osaamistarpeiden ennakoinnille ja tulevaisuuden suunnittelulle. Esi-miesosaaminen vaikuttaa merkittävästi siihen, miten hyvin organisaatioissa pystytään hyö-dyntämään sen muuta inhimillistä pääomaa ja tämä tutkimus osallistuu keskusteluun siitä, millä tavalla esimiesosaamisen tulisi kehittyä, jotta se pystyy vastaamaan käynnissä ole-vaan yhteiskunnalliseen, sosiaaliseen ja teknologiseen muutokseen. Tutkimuksen tavoit-teena on ennakoida digitaalisen murroksen keskellä olevan media- ja kustannusalan orga-nisaation esimiesosaamisessa tarvittavia muutoksia. Tutkimus on luonteeltaan laadullinen ja primääritutkimusaineisto koostuu kohdeorganisaatiossa esimiesten, toimitusjohtajan ja henkilöstöpäällikön haastatteluista. Tutkimuksen mukaan tulevaisuudessa tarvittavat esimiesosaamiset eivät merkittävästi eroa tämän päivän paradigman mukaisista osaamisista. Monien osaamisten merkitys kuitenkin korostuu. Esimiesten ja muiden työntekijöiden osaamisten nähdään lähestyvän toisiaan ja tulevaisuudessa rajat esimiesten ja tiimiläisten osaamistarpeiden välillä vähenevät entises-tään. Esimiestyössä monet osaamistarpeet, kuten esimerkiksi epävarmuuden sietokyky, kuitenkin korostuvat. Esimiehen merkittävänä tehtävänä nähdään jatkossa entistä vah-vemmin vastuunkantaminen työyhteisössä.

Flow in porous media of oil-water systems

Fluid flow behaviour in porous media is a conundrum. Therefore, this research is focused on filtration-volumetric characterisation of fractured-carbonate sediments, coupled with their proper simulation. For this reason, at laboratory rock properties such as pore volume, permeability and porosity are measured, later phase permeabilities and oil recovery in function of flow rate are assessed. Furthermore, the rheological properties of three oils are measured and analysed. Finally based on rock and fluid properties, a model using COMSOL Multiphysics is built in order to compare the experimental and simulated results. The rock analyses show linear relation between flow rate and differential pressure, from which phase permeabilities and pressure gradient are determined, eventually the oil recovery under low and high flow rate is established. In addition, the oils reveal thixotropic properties as well as non-Newtonian behaviour described by Bingham model, consequently Carreau viscosity model for the used oil is given. Given these points, the model for oil and water is built in COMSOL Multiphysics, whereupon successfully the reciprocity between experimental and simulated results is analysed and compared. Finally, a two-phase displacement model is elaborated.

Media muuttuu ja muuttaa

Kirjallisuusarvostelu

Formal modelling for digital media distribution

Human beings have always strived to preserve their memories and spread their ideas. In the beginning this was always done through human interpretations, such as telling stories and creating sculptures. Later, technological progress made it possible to create a recording of a phenomenon; first as an analogue recording onto a physical object, and later digitally, as a sequence of bits to be interpreted by a computer. By the end of the 20th century technological advances had made it feasible to distribute media content over a computer network instead of on physical objects, thus enabling the concept of digital media distribution. Many digital media distribution systems already exist, and their continued, and in many cases increasing, usage is an indicator for the high interest in their future enhancements and enriching. By looking at these digital media distribution systems, we have identified three main areas of possible improvement: network structure and coordination, transport of content over the network, and the encoding used for the content. In this thesis, our aim is to show that improvements in performance, efficiency and availability can be done in conjunction with improvements in software quality and reliability through the use of formal methods: mathematical approaches to reasoning about software so that we can prove its correctness, together with the desirable properties. We envision a complete media distribution system based on a distributed architecture, such as peer-to-peer networking, in which different parts of the system have been formally modelled and verified. Starting with the network itself, we show how it can be formally constructed and modularised in the Event-B formalism, such that we can separate the modelling of one node from the modelling of the network itself. We also show how the piece selection algorithm in the BitTorrent peer-to-peer transfer protocol can be adapted for on-demand media streaming, and how this can be modelled in Event-B. Furthermore, we show how modelling one peer in Event-B can give results similar to simulating an entire network of peers. Going further, we introduce a formal specification language for content transfer algorithms, and show that having such a language can make these algorithms easier to understand. We also show how generating Event-B code from this language can result in less complexity compared to creating the models from written specifications. We also consider the decoding part of a media distribution system by showing how video decoding can be done in parallel. This is based on formally defined dependencies between frames and blocks in a video sequence; we have shown that also this step can be performed in a way that is mathematically proven correct. Our modelling and proving in this thesis is, in its majority, tool-based. This provides a demonstration of the advance of formal methods as well as their increased reliability, and thus, advocates for their more wide-spread usage in the future.

Characterization of the filter media used in the dual media filter

The removal of organics from copper electrolyte solutions after solvent extraction by dual media filtration is one of the most efficient ways to ensure the clean electrolyte flow into the electrowinning. The clean electrolyte will ensure the good quality cathode plate production. Dual media filtration uses two layers of filter media for filtration as anthracite and garnet respectively. The anthracite layer will help the coalescing of the entrained organic droplets which will then float to the top of the filter, and back to the solvent extraction process. The garnet layer will catch any solids left in the electrolyte traveling through the filter media. This thesis will concentrate on characterization of five different anthracites in order to find some differences using specific surface area analysis, particle size analysis, and morphology analysis. These results are compared to the pressure loss values obtained from lab column tests and bed expansion behavior. The goal of the thesis was to find out if there were any differences in the anthracite which would make the one perform better than the other. There were no big differences found on any aspect of the particle characterization, but some found differences should be further studied in order to confirm the meaning of the porosity, surface area, intensity mean and intensity SD (Standard Deviation) on anthracites and their use in dual media filtration. The thesis work analyzed anthracite samples the way that is not found on any public literature sources, and further studies on the issue would bring more knowledge to the electrolyte process.

Forecasting with social media – Using Facebook likes to predict the results of the 2015 Finnish Parliamentary elections

Already one-third of the human population uses social media on a daily basis. The biggest social networking site Facebook has over billion monthly users. As a result, social media services are now recording unprecedented amount of data on human behavior. The phenomenon has certainly caught the attention of scholars, businesses and governments alike. Organizations around the globe are trying to explore new ways to benefit from the massive databases. One emerging field of research is the use of social media in forecasting. The goal is to use data gathered from online services to predict offline phenomena. Predicting the results of elections is a prominent example of forecasting with social media, but regardless of the numerous attempts, no reliable technique has been established. The objective of the research is to analyze how accurately the results of parliament elections can be forecasted using social media. The research examines whether Facebook “likes” can be effectively used for predicting the outcome of the Finnish parliament elections that took place in April 2015. First a tool for gathering data from Facebook was created. Then the data was used to create an electoral forecast. Finally, the forecast was compared with the official results of the elections. The data used in the research was gathered from the Facebook walls of all the candidates that were running for the parliament elections and had a valid Facebook page. The final sample represents 1131 candidates and over 750000 Facebook “likes”. The results indicate that creating a forecast solely based on Facebook “likes” is not accurate. The forecast model predicted very dramatic changes to the Finnish political landscape while the official results of the elections were rather moderate. However, a clear statistical relationship between “likes” and votes was discovered. In conclusion, it is apparent that citizens and other key actors of the society are using social media in an increasing rate. However, the volume of the data does not directly increase the quality of the forecast. In addition, the study faced several other limitations that should be addressed in future research. Nonetheless, discovering the positive correlation between “likes” and votes is valuable information that can be used in future studies. Finally, it is evident that Facebook “likes” are not accurate enough and a meaningful forecast would require additional parameters.

Teknologiazombie – Sosiaalinen media arjessa

Tutkielman tavoitteena on tutkia teknologian ja sosiaalisen median vaikutusta yksilön arkeen, sekä selvittää, miten saatavilla olevan tiedon määrä näkyy yksilön arkielämässä ja mitä oheisvaikutuksia jatkuvalla tietovirralla ja aktiivisella sosiaalisen median käytöllä on. Lisäksi tavoitteena on muodostaa kuva siitä, miten yhteisöverkkopalvelut ja kokoaikaisen tavoitettavuuden vaatimus vaikuttavat arkeen ja mitä mahdollisia seuraamuksia aktiivisella sosiaalisen median käytöllä on. Tutkielma vastaa seuraaviin kysymyksiin: Katoaako yksityisyyden rajat tulevaisuudessa? Miten lisääntyvä sosiaalisen median käyttö vaikuttaa ihmisten keskinäiseen vuorovaikutukseen työssä ja yksityiselämässä? Kysymyksiin vastataan muodostamalla kattava kuva mobiili- ja verkkopalveluiden aiheuttamista arjen muutoksista, sekä sosiaalisen median käytön nykytilasta. Sosiaalisen median nykytilan tarkastelu keskittyy sosiaalisen median kehitykseen sekä yhteisöverkkopalveluiden suosituimpiin muotoihin. Erityisesti käydään läpi miten palveluita voidaan kategorisoida, sekä miten ne eroavat toisistaan. Tutkielman lopussa keskitytään sosiaalisen median vaikutuksiin: mitä positiivista ja negatiivista yhteisöpalveluiden käytössä on ja miten ne näkyvät niin työ- kuin arkielämässä. Tutkielman tuloksena todetaan, että sosiaalisen median aktiivinen käyttö hämärtää yksityisen ja julkisen tiedon rajaa, sillä sosiaalisessa mediassa yksityiseksi tarkoitettu viesti tai kuva voi levitä merkittävästi laajemmalle yleisölle. Kun epäsuotuisa julkaisu on tehty, on yksityisyys menetetty eikä julkaistua tietoa voi enää täysin poistaa verkosta. Tämä ominaisuus voi aiheuttaa epäsuotuisia sosiaalisia tilanteita etenkin silloin, kun käyttäjän medialukutaito tai teknologiaosaaminen ovat matalalla tasolla. Sosiaalinen yhteydenpito on yhä useamman virtuaalista, mikä edellyttää kykyä ja halua hyödyntää verkkopalveluita madaltuneen yksityisyyden kustannuksella.