Competition between ferromagnetism and antiferromagnetism in the rutile Cr1-xVxO2 system

We present a comprehensive computational and experimental examination of the Cr1−xVxO2 (0 ≤ x ≤ 0.5) system. The entire series crystallizes in the rutile structure, but the compounds exhibit significantly different magnetic properties depending on x. Lattice parameter a increases linearly with x, but the c parameter is slightly reduced due to vanadium-vanadium bonding. The V-for-Cr substitution creates Cr3+-V5+ pairs; this leads to competition between ferromagnetic (Cr4+-Cr4+) and antiferromagnetic (Cr3+-Cr3+) interactions such that the materials change from ferromagnetic to antiferromagnetic with increasing x. Weak ferromagnetic interactions arising from Cr4+ are observed even in the seemingly antiferromagnetic phases with the exception of x = 0.5, which contains only Cr3+. Density functional theory calculations are performed, but they incorrectly predict the x = 0.5 phase to be a half-metal. This is caused by an incorrect prediction of the oxidation states of chromium and vanadium.Peer reviewe

The use and perceived impact of external support services in SME internationalization process

SMEs do not always possess the resources needed for internationalization. This lack of resources, both tacit and tangible along with international competition has brought forth a number of internationalization support services available for SMEs. These support activities are mainly focused on exporting as an entry mode and their purpose is to facilitate growth in SMEs that benefits both the company and country they reside in. The purpose of this master’s thesis is to determine the impact and use of internationalization support in SME internationalization process. By analyzing the needs of the companies and the criteria and form of support external support services provide, we are able to see the problems in allocating internationalization support for companies and whether internationalization support has the wanted impact on SME internationalization. In addition the organizational development of internationalization services is looked upon and theorized if there is room for improvement regarding the allocation of support for SMEs. The study was conducted as a qualitative case analysis of two Finnish companies and two internationalization support service providers. The interviews were decoded into themes that included SME internationalization process, the use and impact of internationalization support and internationalization support organizations. Theoretical approach is applied to the analysis. The results of the study revealed firstly, that external support is offered too late in the SME internationalization process and firms would like to utilize external support earlier in their internationalization. Secondly, the internationalization support providers lack the tools to help companies that are fast in their internationalization process and operate at a loss for the first years of their development. Thirdly, optimal form of support is discussed. These findings are helpful in planning internationalization support programs for start-ups and internationalizing SMEs in Finland

Matrix metalloproteinase MMP-2 and MMP-9 and their inhibitors TIMP-1 and TIMP-2 in bladder carcinoma

AbstractBladder cancer when superficial has a good prognosis but it has a high recurrence risk and about 10–15% of the superficial carcinomas will progress into muscle invasive or metastatic type. The most powerful factor for predicting the behavior of bladder carcinoma is the stage of the tumor. Invasion to the lamina propria increases the risk of recurrence and progress to muscle-invasive tumor. Also grade of the tumor and tumor multiplicity associates with high risk for recurrence. New markers are still needed to find those patients who need more and better treatments to avoid the recurrence and progress. The need for new non-invasive markers to diminish the need for frequent cystoscopy in follow-up is also obvious.Gelatinases MMP-2 and MMP-9 are known to associate to tumor invasion and progression. Also their tissue inhibitors TIMP-1 and TIMP-2 take part in these diversified processes and metastasis formation. In the present work the expression and clinical value of gelatinases MMP-2 and MMP-9 and their tissue inhibitors TIMP-1 and TIMP-2 were evaluated in bladder carcinoma. Primary tissue samples of 121 patients were analyzed for expression of MMP-2 and/or MMP-9 using immunohistochemistry. The serum samples of 87 patients who were treated in the Oncology Department of Oulu University Hospital were collected and studied with ELISA. The control group consisted of 44 healthy volunteers.Overexperssion of MMP-2 protein correlated significantly to disease-specific survival and showed an independent prognostic value as a biomarker. High MMP-9 expression instead correlated to favorable overall survival of bladder cancer patients. Circulating proMMP-2, TIMP-2 and MMP-2:TIMP-2 complex levels were lower in cancer patients than in healthy volunteers in control group. High levels of all these three markers correlated with better prognosis in bladder cancer patients.Academic Dissertation to be presented, with the assent of the Faculty of Medicine of the University of Oulu, for public defence in Auditorium 7 of Oulu University Hospital, on October 31st, 2008, at 12 noonAbstract Bladder cancer when superficial has a good prognosis but it has a high recurrence risk and about 10–15% of the superficial carcinomas will progress into muscle invasive or metastatic type. The most powerful factor for predicting the behavior of bladder carcinoma is the stage of the tumor. Invasion to the lamina propria increases the risk of recurrence and progress to muscle-invasive tumor. Also grade of the tumor and tumor multiplicity associates with high risk for recurrence. New markers are still needed to find those patients who need more and better treatments to avoid the recurrence and progress. The need for new non-invasive markers to diminish the need for frequent cystoscopy in follow-up is also obvious. Gelatinases MMP-2 and MMP-9 are known to associate to tumor invasion and progression. Also their tissue inhibitors TIMP-1 and TIMP-2 take part in these diversified processes and metastasis formation. In the present work the expression and clinical value of gelatinases MMP-2 and MMP-9 and their tissue inhibitors TIMP-1 and TIMP-2 were evaluated in bladder carcinoma. Primary tissue samples of 121 patients were analyzed for expression of MMP-2 and/or MMP-9 using immunohistochemistry. The serum samples of 87 patients who were treated in the Oncology Department of Oulu University Hospital were collected and studied with ELISA. The control group consisted of 44 healthy volunteers. Overexperssion of MMP-2 protein correlated significantly to disease-specific survival and showed an independent prognostic value as a biomarker. High MMP-9 expression instead correlated to favorable overall survival of bladder cancer patients. Circulating proMMP-2, TIMP-2 and MMP-2:TIMP-2 complex levels were lower in cancer patients than in healthy volunteers in control group. High levels of all these three markers correlated with better prognosis in bladder cancer patients

Characterization of magnetic properties of Sr2CuWO6 and Sr2CuMoO6

In this work we examine the low-temperature magnetic properties of the two double-perovskite compounds Sr2CuWO6 and Sr2CuMoO6 using magnetic susceptibility, muon spin rotation and relaxation, and neutron powder diffraction measurements. Additionally, the most relevant spin exchange interaction constants are derived from ab initio electronic structure calculations, aided by x-ray absorption spectroscopy. The compounds exhibit quasi-two-dimensional magnetic properties, with broad maxima at Tmax = 83 and 95 K for Sr2CuWO6 and Sr2CuMoO6, respectively. However, three-dimensional long-range order takes place below TN = 24(1) and 28(2) K for Sr2CuWO6 and Sr2CuMoO6, respectively. Our results show that the low-dimensional magnetic correlations are mainly due to the significant next-nearest-neighbor interactions in the ab plane of the double-perovskite structure, whereas three-dimensional long-range magnetic order is caused by weaker next-nearest-neighbor interactions along the c axis. Next-nearest-neighbor interactions are also slightly frustrated by weaker nearest-neighbor interactions within the ab plane. Based on these results we predict the low-temperature magnetic structure in these compounds to be type-II antiferromagnetic order of the double-perovskite lattice.Peer reviewe

Characterization of <em>Lactobacillus</em> bacteriophage LL-H genes and proteins having biotechnological interest

AbstractTwo regions of the genome of the Lactobacillus delbrueckii subsp. lactis bacteriophage LL-H were characterized, representing 14% of the phage genome. The first region of 2497 bp contained genes encoding phage structural proteins and the second region of 2498 bp genes involved in lytic functions. The nucleotide sequences of the major capsid protein gene g34, a putative capsid morphogenesis gene (ORF178A), the gene mur encoding phage cell wall hydrolase (lysin), the gene hol (ORF107) encoding the cell membrane permeabilizing phage holin, and six other genes with unknown function were found. Identification of these genes was performed by amino acid sequencing of their encoded proteins (genes g34 and mur), by their physiological effect on E. coli (genes hol and mur), by sequence comparison (genes mur, hol, ORF178A), and by biochemical analysis of their encoded purified protein (gene mur). A promoter for the capsid protein encoding gene cluster was determined by primer extension method. A purification method suitable for large scale processing (cation exchange chromatography by expanded bed adsorption method) was developed for the phage LL-H lysin protein Mur. Purified Mur was biochemically determined as a N-acetylmuramidase, which was effective on cell walls of Lb. delbrueckii, Lb. helveticus, Lb. acidophilus and Pediococcus damnosus. Some biotechnological applications for the lysis genes hol and mur or the purified protein Mur are suggested. Mur digests E. coli cell walls inefficiently, but could still be used for lysis of E. coli. Coexpression of the phage LL-H lysin and holin genes yielded to lysis of the E. coli host only at low culture densities. Therefore, some chemicals were tested for their ability to trigger lysis of E. coli cells over expressing the phage LL-H gene mur. Thymol was found to mimic the physiological effects of the phage holin in a bacterial growth state independent manner. An efficient lysis method utilizing intracellular production of Mur and triggering the lysis with thymol was developed.Academic Dissertation to be presented with the assent of the Faculty of Science, University of Oulu, for public discussion in Raahensali (Auditorium L 10), Linnanmaa, on November 28th, 1998, at 12 noon.Abstract Two regions of the genome of the Lactobacillus delbrueckii subsp. lactis bacteriophage LL-H were characterized, representing 14% of the phage genome. The first region of 2497 bp contained genes encoding phage structural proteins and the second region of 2498 bp genes involved in lytic functions. The nucleotide sequences of the major capsid protein gene g34, a putative capsid morphogenesis gene (ORF178A), the gene mur encoding phage cell wall hydrolase (lysin), the gene hol (ORF107) encoding the cell membrane permeabilizing phage holin, and six other genes with unknown function were found. Identification of these genes was performed by amino acid sequencing of their encoded proteins (genes g34 and mur), by their physiological effect on E. coli (genes hol and mur), by sequence comparison (genes mur, hol, ORF178A), and by biochemical analysis of their encoded purified protein (gene mur). A promoter for the capsid protein encoding gene cluster was determined by primer extension method. A purification method suitable for large scale processing (cation exchange chromatography by expanded bed adsorption method) was developed for the phage LL-H lysin protein Mur. Purified Mur was biochemically determined as a N-acetylmuramidase, which was effective on cell walls of Lb. delbrueckii, Lb. helveticus, Lb. acidophilus and Pediococcus damnosus. Some biotechnological applications for the lysis genes hol and mur or the purified protein Mur are suggested. Mur digests E. coli cell walls inefficiently, but could still be used for lysis of E. coli. Coexpression of the phage LL-H lysin and holin genes yielded to lysis of the E. coli host only at low culture densities. Therefore, some chemicals were tested for their ability to trigger lysis of E. coli cells over expressing the phage LL-H gene mur. Thymol was found to mimic the physiological effects of the phage holin in a bacterial growth state independent manner. An efficient lysis method utilizing intracellular production of Mur and triggering the lysis with thymol was developed

Haasteena kongressipalveluiden konseptointi

Tämän tutkimuksen tarkoitus oli tutkia miten palvelukonseptia voidaan kehittää asiakkaiden ostopäätösprosessiin vaikuttavien tekijöiden pohjalta. Ensimmäisenä tavoitteena oli mallintaa palvelukonseptin keskeisimmät elementit kehittämisen kannalta. Tutkimuksen teoriaosuudessa tuotiin esille miten palvelua voidaan kehittää palveluihin- ja matkailuun liittyvien teorioiden pohjalta. Keskeistä kehittämisen kannalta on ymmärtää palveluiden ominaispiirteet, palvelun laatuun vaikuttavat tekijät sekä mitä asioita matkailutuotteen kehittämisessä on hyvä huomioida. Toisena tavoitteena oli tuoda esille keskeiset teemat kongressijärjestäjien odotuksiin perustuvassa palvelukonseptin kehittämisessä. Ongelmaa lähestyttiin tuomalla teoriassa esille kongressimatkailun ominaispiirteitä ja tarkastelemalla kongressijärjestäjien ostopäätösprosesseja sekä tekijöitä, jotka vaikuttavat ostopäätösprosesseihin. Kolmantena tavoitteena oli tutkimuksen empiirisessä osassa tuottaa tietoa siitä miten kongressijärjestäjien ostopäätöskriteerejä voidaan hyödyntää palvelukonseptin kehittämisessä kongressimatkailussa Levin ympäristössä. Ostopäätösprosesseja ja ostopäätöskriteerejä tutkittiin teemahaastatteluiden avulla. Tutkimukseen osallistuneet muodostivat hyvin heterogeenisen kohderyhmän, joten tutkimustulokset eivät ole yleistettävissä. Tutkimustulosten perusteella voidaan todeta, että teoria indikoi joitain haastatteluissa esiin nousseita asioita. Tämän tutkimuksen perusteella ei pystytä todentamaan teoriaa, mutta tutkimus syventää käsitystä yhdistysten ja järjestöjen ostopäätösprosesseista ja tekijöistä, jotka vaikuttavat kongressipaikan valintaan. Tietoa voidaan hyödyntää kongressipalveluiden suunnittelussa ja ideoinnissa.fi=Opinnäytetyö kokotekstinä PDF-muodossa.|en=Thesis fulltext in PDF format.|sv=Lärdomsprov tillgängligt som fulltext i PDF-format

High-yield production of biologically active recombinant protein in shake flask culture by combination of enzyme-based glucose delivery and increased oxygen transfer

This report describes the combined use of an enzyme-based glucose release system (EnBase®) and high-aeration shake flask (Ultra Yield Flask™). The benefit of this combination is demonstrated by over 100-fold improvement in the active yield of recombinant alcohol dehydrogenase expressed in E. coli. Compared to Terrific Broth and ZYM-5052 autoinduction medium, the EnBase system improved yield mainly through increased productivity per cell. Four-fold increase in oxygen transfer by the Ultra Yield Flask contributed to higher cell density with EnBase but not with the other tested media, and consequently the product yield per ml of EnBase culture was further improved

Cheese whey-induced high-cell-density production of recombinant proteins in Escherichia coli

BACKGROUND: Use of lactose-rich concentrates from dairy processes for the induction of recombinant gene's expression has not received much attention although they are interesting low cost substrates for production of recombinant enzymes. Applicability of dairy waste for induction of recombinant genes in Escherichia coli was studied. Clones expressing Lactobacillus phage muramidase and Lactobacillus alcohol dehydrogenase were used for the experiments. RESULTS: Shake flask cultivations in mineral salt medium showed that cheese whey or deproteinised whey induced gene expression as efficiently as IPTG (isopropyl-β-D-thiogalactopyranoside) or pure lactose. Addition of yeast extract or proteolytically degraded whey proteins did not improve the recombinant protein yield. In contrast, addition of yeast extract to the well-balanced mineral salt medium decreased the product yield. Feeding with glycerol provided sufficient amount of easily assimilable carbon source during the induction period without preventing lactose intake and induction by lactose. High-cell-density fed-batch cultivations showed that product yields comparable to IPTG-induction can be achieved by feeding bacteria with a mixture of glycerol and concentrated whey permeate during the induction. CONCLUSION: Whey and concentrated whey permeate can be applied as an alternative inducer in recombinant high-cell-density fed-batch fermentations. The yield of the recombinant product was comparable to fermentations induced by IPTG. In low-cell-density shake flask experiments the yield was higher with whey or whey permeate than with IPTG