Design yrityksen viestintäfunktiona – Designin rooli yrityksen identiteetin viestijänä, sidosryhmäviestinnän ja maineen rakentamisen välineenä

Designin rooli yhteiskunnallisessa keskustelussa on tullut vahvasti esiin viime vuosina. Suur-Helsingin (Helsinki, Espoo, Vantaa, Kauniainen ja Lahti) voittama World Design Capital 2012 -titteli on lisännyt osaltaan designiin kiinnittyvää huomiota. Designiin liittyvät ulottuvuudet ovat laajat ja sen tuoma lisäarvo yrityksille on mielenkiintoinen tutkimuskohde, johon voidaan yhdistää myös viestinnän näkökulma. Design on siis muutakin kuin esineiden muotoilua ja suunnittelua. Designia on tutkittu muun muassa artefaktien kautta kommunikaatiovälineenä, mutta designin roolia yritysviestinnässä ei ole juurikaan aikaisemmin tutkittu. Tämän pro gradu -työn tarkoituksena on selvittää, miten design voi toimia yrityksen viestintäfunktiona. Tämän päätutkimuskysymyksen selvittämiseksi etsitään vastaus kolmeen alakysymykseen, jotka perustuvat Joep Cornelissenin yritysviestinnän teorian kolmeen pääkäsitteeseen: yrityksen identiteettiin, sidosryhmäviestintään ja maineeseen. Joep Cornelissenin yritysviestintäteoria on myös tutkimuksen päälähde, jonka lisäksi muun muassa Pekka Aulan maineteorioilla on keskeiset roolinsa. Tutkimuksen aineisto on kerätty teemahaastatteluilla. Haastatteluja tehtiin yhteensä yksitoista ja ne on kerätty niin sanotulla lumipallo-otannalla. Kohderyhmänä olivat designalan ammattilaiset. Noin puolet haastateltavista tekee tutkimus- ja opetustyötä eri yliopistoissa, yksi kaupungin palveluksessa ja loput toimivat eri yrityksissä joissakin johtotehtävissä. Kolmen haastateltavan toimipaikka sijaitsee Lahdessa, yhden Espoossa ja muiden Helsingissä. Analyysimenetelmänä on käytetty niin ikään teemoittelua. Haastatteluaineistosta etsittiin kunkin yritysviestinnän teoriaan perustuvien teemojen yhteyttä designiin, ja yritettiin tulkita, millainen viestinnällinen rooli designilla voisi niissä olla. Haastateltavien näkemykset designista painottivat sen olevan muotoilun lisäksi luovaa ongelmanratkaisua, maineen-, brändinrakentamisen ja designammattilaisten väline, jolla asioista tehdään helpommin lähestyttäviksi ja hallittaviksi. Designilla on lisäksi strategista merkitystä ja se luo lisäarvoa yrityksille. Tutkimus osoittaa, että design toimii yrityksen viestintäfunktiona, kun se erilaisilla tavoilla ja keinoilla viestii yrityksen identiteettiä, toimii sidosryhmäviestinnän ja maineen rakentamisen välineenä. Erilaiset kansainväliset ja kansalliset muotoilupalkinnot ovat yritysten onnistuneen designtyön mittareita. Lisäksi tutkimusaineistosta nousi esiin kolme johtoteemaa designille, jotka ovat: designin viestintä-, väline- ja inhimillisyysteema. Pro gradu -työni antaa uutta kartoittavana tutkimuksena mielenkiintoista ja ajankohtaista tietoa designin roolista ja sen hyödyntämisestä yritysviestinnässä, mutta se ei anna konkreettisia esimerkkejä tai käytännön työkaluja sen toteuttamiseksi. Jatkotutkimuksen kannalta tätä ajatusta olisi mielekästä viedä eteenpäin.

Kaupunkimaineen rakentuminen. Lahden muotoilumaine epälineaarisena prosessina.

Tämän pro gradu -tutkimuksen aiheena on kaupunkimaineen tarkastelu epälineaarisena ja dynaamisena prosessina. Opinnäytteessä kaupunkimainetta tutkitaan dynaamisen onganisaatioviestinnän teorian näkökulmasta ja sen tarkoitus on hahmotella epälineaarisempaa näkemystä kaupunkimaineen rakentumisesta. Lisäksi työ siirtää kaupunkimainetutkimuksen fokusta maineen mittaamisesta sen leviämisen tutkimiseen. Tarkoituksena on siis hahmottaa sitä, miten kaupungin sisällä syntyvä maine yleisöissään leviää. Tutkimuksen tärkeimmiksi lähteiksi on valikoitu Pekka Aulan dynaamisen organisaatioviestinnän teoria sekä Aulan, Jouni Heinosen, Saku Mantereen sekä Erkki Karvosen mainenäkemykset. Lisäksi tutkimuksessa on hyödynnetty useiden kansainvälisten kaupunkitutkijoiden ajatuksia, joista tärkeimpinä lähteinä tutkimuksen kehittymisen kannalta ovat olleet Elaine Romanellin, Olga M. Khessinan sekä Patsy Healyn työt. Kaupunkia ja sen mainetta käsittelevissä osioissa tärkeään rooliin nousi myös Teppo Sintosen käsitys postmodernista organisaatiosta, jollaisena kaupunki tässä tutkimuksessa nähdään, itse tutkimuksen todellisuuskäsitys on konstruktivistinen - siinä todellisuus eli näin ollen myös kaupunki on yhteisesti rakennettua ja uusiutuu kirjoituksissa sekä puheissa. Lähteiden pohjalta on tutkimuksessa hahmoteltu ajatuksia dynaamisesta kaupunkimaineesta, joka vastaa niin maineteorioiden ajatuksiin, dynaamisen organisaatioviestinnän teorian prepositioihin kuin kriittiseen kaupunkimarkkinoinnin tutkimukseen. Työ onkin vahvasti poikkitieteellinen tutkimus, jonka takia sen teoreettinen osuus onkin erittäin laaja. Teoreettisen osuuden laajuus selittyy myös sillä, että tutkimuksessa lähestyttiin kaupunkimainetta uudesta, epälineaarisemmasta näkökulmasta. Työ on laadullinen tapaustutkimus, jossa maineen epälineaarista rakentumista on tutkittu tapauskaupunki Lahden ja tämän muotoilumaineen näkökulmasta. Tutkimus toteutettiin haastattelututkimuksena ja aineisto analysoitiin narratiiviparadigman teorian alle sijoittuvalla juonellistamisen menetelmällä. Asiantuntijahaastatteluista eritellystä aineistosta johdetut johtopäätökset osoittavat maineen rakentumiseen liittyviä epälineaarisia elementtejä sekä antavat tukea ajatukselle, jonka mukaan kaupunkimaineen tutkimuksessa saattaa olla vaatimuksia epälineaarisemmalle kaupunkimainekäsitykselle. Tutkimuksen johtopäätösten mukaan mainetta voidaan siis tarkastella epälineaarisena prosessina, joka muotoutuu vuorovaikutuksessa ympäristön ja kaupungin välillä, ja joka kehittyy ennustamattomien, luovien ja itseohjautuvien prosessien kautta.

FGF signaling in neurogenesis and patterning of the developing midbrain and anterior hindbrain

Embryonic midbrain and hindbrain are structures which will give rise to brain stem and cerebellum in the adult vertebrates. Brain stem contains several nuclei which are essential for the regulation of movements and behavior. They include serotonin-producing neurons, which develop in the hindbrain, and dopamine-producing neurons in the ventral midbrain. Degeneration and malfunction of these neurons leads to various neurological disorders, including schizophrenia, depression, Alzheimer s, and Parkinson s disease. Thus, understanding their development is of high interest. During embryogenesis, a local signaling center called isthmic organizer regulates the development of midbrain and anterior hindbrain. It secretes peptides belonging to fibroblast growth factor (FGF) and Wingless/Int (Wnt) families. These factors bind to their receptors in the surrounding tissues, and activate various downstream signaling pathways which lead to alterations in gene expression. This in turn affects the various developmental processes in this region, such as proliferation, survival, patterning, and neuronal differentiation. In this study we have analyzed the role of FGFs in the development of midbrain and anterior hindbrain, by using mouse as a model organism. We show that FGF receptors cooperate to receive isthmic signals, and cell-autonomously promote cell survival, proliferation, and maintenance of neuronal progenitors. FGF signaling is required for the maintenance of Sox3 and Hes1 expression in progenitors, and Hes1 in turn suppresses the activity of proneural genes. Loss of Hes1 is correlated with increased cell cycle exit and premature neuronal differentiation. We further demonstrate that FGF8 protein forms an antero-posterior gradient in the basal lamina, and might enter the neuronal progenitors via their basal processes. We also analyze the impact of FGF signaling on the various neuronal nuclei in midbrain and hindbrain. Rostral serotonergic neurons appear to require high levels of FGF signaling in order to develop. In the absence of FGF signaling, these neurons are absent. We also show that embryonic meso-diencephalic dopaminergic domain consists of two populations in the anterior-posterior direction, and that these populations display different molecular profiles. The anterior diencephalic domain appears less dependent on isthmic FGFs, and lack several genes typical of midbrain dopaminergic neurons, such as Pitx3 and DAT. In Fgfr compound mutants, midbrain dopaminergic neurons begin to develop but soon adopt characteristics which highly resemble those of diencephalic dopaminergic precursors. Our results indicate that FGF signaling regulates patterning of these two domains cell-autonomously.

A genome-wide approach accounting for body mass index identifies genetic variants influencing fasting glycemic traits and insulin resistance.

Recent genome-wide association studies have described many loci implicated in type 2 diabetes (T2D) pathophysiology and β-cell dysfunction but have contributed little to the understanding of the genetic basis of insulin resistance. We hypothesized that genes implicated in insulin resistance pathways might be uncovered by accounting for differences in body mass index (BMI) and potential interactions between BMI and genetic variants. We applied a joint meta-analysis approach to test associations with fasting insulin and glucose on a genome-wide scale. We present six previously unknown loci associated with fasting insulin at P < 5 × 10(-8) in combined discovery and follow-up analyses of 52 studies comprising up to 96,496 non-diabetic individuals. Risk variants were associated with higher triglyceride and lower high-density lipoprotein (HDL) cholesterol levels, suggesting a role for these loci in insulin resistance pathways. The discovery of these loci will aid further characterization of the role of insulin resistance in T2D pathophysiology.

The use of future-oriented knowledge in regional innovation processes: Research on knowledge generation, transfer and conversion

The importance of the regional level in research has risen in the last few decades and a vast literature in the fields of, for instance, evolutionary and institutional economics, network theories, innovations and learning systems, as well as sociology, has focused on regional level questions. Recently the policy makers and regional actors have also began to pay increasing attention to the knowledge economy and its needs, in general, and the connectivity and support structures of regional clusters in particular. Nowadays knowledge is generally considered as the most important source of competitive advantage, but even the most specialised forms of knowledge are becoming a short-lived resource for example due to the accelerating pace of technological change. This emphasizes the need of foresight activities in national, regional and organizational levels and the integration of foresight and innovation activities. In regional setting this development sets great challenges especially in those regions having no university and thus usually very limited resources for research activities. Also the research problem of this dissertation is related to the need to better incorporate the information produced by foresight process to facilitate and to be used in regional practice-based innovation processes. This dissertation is a constructive case study the case being Lahti region and a network facilitating innovation policy adopted in that region. Dissertation consists of a summary and five articles and during the research process a construct or a conceptual model for solving this real life problem has been developed. It is also being implemented as part of the network facilitating innovation policy in the Lahti region.

Efectos del consumo de cigarrillo en la presentación y severidad de la dismenorrea

Introducción: La dismenorrea se presenta como una patología cada vez más frecuente en mujeres de 16-30 años. Dentro de los factores asociados a su presentación, el consumo de tabaco ha revelado resultados contradictorios. El objetivo del presente estudio es explorar la asociación entre el consumo de cigarrillo y la presentación de dismenorrea, y determinar si los trastornos del ánimo y la depresión, alteran dicha asociación. Materiales y métodos: Se realizó un estudio de prevalencia analítica en mujeres de la Universidad del Rosario matriculadas en pregrado durante el primer semestre de 2013, para determinar la asociación entre el consumo de tabaco y la presentación de dismenorrea. En el estudio se tuvieron en cuenta variables tradicionalmente relacionadas con dismenorrea, incluyendo las variables ansiedad y depresión como potenciales variables de confusión. Los registros fueron analizados en el programa Estadístico IBM SPSS Statistics Versión 20.0. Resultados: Se realizaron 538 cuestionarios en total. La edad promedio fue 19.92±2.0 años. La prevalencia de dismenorrea se estimó en 89.3%, la prevalencia de tabaquismo 11.7%. No se encontró una asociación entre dismenorrea y tabaquismo (OR 3.197; IC95% 0.694-14.724). Dentro de las variables analizadas, la depresión y la ansiedad constituyen factores de riesgo independientes para la presentación de dismenorrea con una asociación estadísticamente significativa p=0.026 y p=0.024 respectivamente. El análisis multivariado encuentra como factor determinante en la presentación de dismenorrea, la interacción de depresión y ansiedad controlando por las variables tradicionales p<0.0001. Sin embargo, esta asociación se pierde cuando se analiza en la categoría de dismenorrea severa y gana relevancia el uso de métodos de anticoncepción diferentes a los hormonales, mientras que el hecho de haber iniciado la vida sexual presenta una tendencia limítrofe de riesgo. Conclusiones: No se puede demostrar que el tabaco es un factor asociado a la presentación de dismenorrea. Los trastornos del ánimo y la ansiedad constituyen factores determinantes a la presentación de dismenorrea independientemente de la presencia de otros concomitantes. Las variables de asociación se modifican cuando la variable dependiente se categoriza en su estado más severo. Se necesitan estudios más amplios y detallados para establecer dicha asociación.

Association of vitamin D status with arterial blood pressure and hypertension risk: a mendelian randomisation study

BACKGROUND: Low plasma 25-hydroxyvitamin D (25[OH]D) concentration is associated with high arterial blood pressure and hypertension risk, but whether this association is causal is unknown. We used a mendelian randomisation approach to test whether 25(OH)D concentration is causally associated with blood pressure and hypertension risk. METHODS: In this mendelian randomisation study, we generated an allele score (25[OH]D synthesis score) based on variants of genes that affect 25(OH)D synthesis or substrate availability (CYP2R1 and DHCR7), which we used as a proxy for 25(OH)D concentration. We meta-analysed data for up to 108 173 individuals from 35 studies in the D-CarDia collaboration to investigate associations between the allele score and blood pressure measurements. We complemented these analyses with previously published summary statistics from the International Consortium on Blood Pressure (ICBP), the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium, and the Global Blood Pressure Genetics (Global BPGen) consortium. FINDINGS: In phenotypic analyses (up to n=49 363), increased 25(OH)D concentration was associated with decreased systolic blood pressure (β per 10% increase, -0·12 mm Hg, 95% CI -0·20 to -0·04; p=0·003) and reduced odds of hypertension (odds ratio [OR] 0·98, 95% CI 0·97-0·99; p=0·0003), but not with decreased diastolic blood pressure (β per 10% increase, -0·02 mm Hg, -0·08 to 0·03; p=0·37). In meta-analyses in which we combined data from D-CarDia and the ICBP (n=146 581, after exclusion of overlapping studies), each 25(OH)D-increasing allele of the synthesis score was associated with a change of -0·10 mm Hg in systolic blood pressure (-0·21 to -0·0001; p=0·0498) and a change of -0·08 mm Hg in diastolic blood pressure (-0·15 to -0·02; p=0·01). When D-CarDia and consortia data for hypertension were meta-analysed together (n=142 255), the synthesis score was associated with a reduced odds of hypertension (OR per allele, 0·98, 0·96-0·99; p=0·001). In instrumental variable analysis, each 10% increase in genetically instrumented 25(OH)D concentration was associated with a change of -0·29 mm Hg in diastolic blood pressure (-0·52 to -0·07; p=0·01), a change of -0·37 mm Hg in systolic blood pressure (-0·73 to 0·003; p=0·052), and an 8·1% decreased odds of hypertension (OR 0·92, 0·87-0·97; p=0·002). INTERPRETATION: Increased plasma concentrations of 25(OH)D might reduce the risk of hypertension. This finding warrants further investigation in an independent, similarly powered study.

2-(4,5,6,7-tetrafluorobenzimidazol-2-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl, a hydrogen-bonded organic quasi-1D ferromagnet

The title radical (F4BlmNN) is a stable nitronylnitroxide that forms hydrogen-bonded NH center dot center dot center dot ON chains in the solid state. The chains assemble the F4BlmNN molecules to form stacked contacts between the radical groups, in a geometry that is expected to exhibit ferromagnetic (FM) exchange based on spin polarization (SP) models. The experimental magnetic susceptibility of F4BlmNN confirms the expectation, showing 1-D Heisenberg chain FM exchange behavior over 1.8-300 K with an intrachain exchange constant Of J(chain)/k = +22 K. At lower temperatures, ac magnetic susceptibility and variable field heat capacity measurements show that F4BlmNN acts as a quasi-1-D ferromagnet. The dominant ferromagnetic exchange interaction is attributable to overlap between spin orbitals of molecules within the hydrogen-bonded chains, consistent with the SP model expectations. The chains appear to be antiferromagnetically exchange coupled, giving cusps in the ac susceptibility and zero field heat capacity at lower temperatures. The results indicate that the sample orders magnetically at about 0.7 K. The magnetic heat capacity ordering cusp shifts to lower temperatures as external magnetic field increases, consistent with forming a bulk antiferromagnetic phase below a Neel temperature of T-N(0) = 0.72 K, with a critical field of H-c approximate to 1800 Oe. The interchain exchange is estimated to be zJ/k congruent to (-)0.1 K.

Loops, Chains, Sheets, and Networks from Variable Coordination of Cu(hfac)(2) with a Flexibly Hinged Aminoxyl Radical Ligand

One pair of reactants, Cu(hfac)(2) = M and the hinge-flexible radical ligand 5-(3-N-tert-butyl-N-aminoxylphenyl)pyrimidine (3PPN = L), yields a diverse set of five coordination complexes: a cyclic loop M(2)L(1) dimer; a 1:1 cocrystal between an M(2)L(2) loop and an ML(2) fragment; a ID chain of M(2)L(2) loops linked by M; two 2D M(3)L(2) networks of (M-L)(n) chains crosslinked by M with different repeat length pitches; a 3D M(3)L(2) network of M(2)L(2) loops cross-linking (M-L)(n)-type chains with connectivity different from those in the 2D networks. Most of the higher dimensional complexes exhibit reversible, temperature-dependent spin-state conversion of high-temperature paramagnetic states to lower magnetic moment states having antiferromagnetic exchange within Cu-ON bonds upon cooling, with accompanying bond contraction. The 3D complex also exhibited antiferromagnetic exchange between Cu(II) ions linked in chains through pyrimidine rings.

Isostructural M(RL)(2)(hfac)(2) complexes with RL=5-(4-[N-tert-butyl-N-aminoxyl]phenyl)pyrimidine

5-(4-(N-tert-Butyl-N-aminoxylphenyl)) pyrimidine (RL, 4PPN) forms crystallographically isostructural and isomorphic pseudo-octahedral M(RL)(2)(hfac)(2) complexes with M(hfac)(2), M = Zn, Cu, Ni, Co, and Mn. Multiple close contacts occur between sites of significant spin density of the organic radical units. Magnetic behavior of the Zn, Cu, Ni, Co complexes appears to involve multiple exchange pathways, with multiple close crystallographic contacts between sites that EPR (of 4PPN) indicates to have observable spin density. Powder EPR spectra at room temperature and low temperature are reported for each complex. Near room temperature, the magnetic moments of the complexes are roughly equal to those expected by a sum of non-interacting moments (two radicals plus ion). As temperature decreases, AFM exchange interactions become evident in all of the complexes. The closest fits to the magnetic data were found for a 1-D Heisenberg AFM chain model in the Zn(II) complex (J/k = (-)7 K), and for three-spin RL-M-RL exchange in the other complexes (J/k = (-)26 K, (-)3 K, (-) 6 K, for Cu(II), Ni(II), and Co(II) complexes, respectively). (C) 2008 Elsevier B.V. All rights reserved.

Meat consumption among 18-month-old children participating in the Childhood Asthma Prevention Study

Objective: To document meat consumption among 18-month-old children, for use in refining population dietary assessment methods and dietary guidance for young children.

Design: A secondary analysis of data collected in 1998-2000 from the 18 months follow up of the Childhood Asthma Prevention Study: an intervention trial of omega-3 oil supplementation and house-dust mite reduction, from birth to five years.

Subjects and setting: Pregnant women whose unborn children had an atopic family history were recruited from antenatal clinics of six hospitals in western Sydney. Carers of 429 18-month-old children (80% response) satisfactorily completed three-day weighed food records.

Main outcome measures: Mean and median intakes per day and portion sizes of various meats and meat products.

Statistical analyses: T-tests for comparing gender differences; Pearson correlation and one-way analysis of variance for relationships between meat and nutrient intake.

Results: During the recording period 94% of the children ate meat. McDonald's Chicken McNuggets^TM, beef mince, and beef sausages were the most frequently consumed meats. Median portion sizes ranged from 20-50 g, and were considerably smaller than 'usual' portions specified on food frequency questionnaires in common use. Higher meat diets in this age group were not associated with higher intakes of iron or zinc per MJ.

Conclusion: The marginally low intakes of iron and zinc in this age group could be improved by greater use of cuts of red meat appropriately prepared for toddlers.

Consumption of 'extra' foods (energy-dense, nutrient poor) among children aged 16-24 months from western Sydney, Australia

Objective: This study evaluates the contribution of energy-dense, nutrient-poor ‘extra’ foods to the diets of 16–24-month-old children from western Sydney, Australia.

Design:   An analysis of cross-sectional data collected on participants in the Childhood Asthma Prevention Study (CAPS), a randomised trial investigating the primary prevention of asthma from birth to 5 years. We collected 3-day weighed food records, calculated nutrient intakes, classified recorded foods into major food groups, and further classified foods as either ‘core’ or ‘extras’ according to the Australian Guide to Healthy Eating.

Setting:  Pregnant women, whose unborn child was at risk of developing asthma because of a family history, were recruited from all six hospitals in western Sydney, Australia. Data for this study were collected in clinic visits and at participants’ homes at the 18-month assessment.

Participants: Four hundred and twenty-nine children participating in the CAPS study; 80% of the total cohort.

Results:  The mean consumption of ‘extra’ foods was xs223C150 g day− 1 and contributed 25–30% of the total energy, fat, carbohydrate and sodium to the diets of the study children. ‘Extra’ foods also contributed around 20% of fibre, 10% of protein and zinc, and about 5% of calcium. Children in the highest quintile of ‘extra’ foods intake had a slightly higher but not significantly different intake of energy from those in the lowest quintile. However, significant differences were evident for the percentage of energy provided by carbohydrate and sugars (higher) and protein and saturated fat (lower). The intake of most micronutrients was also significantly lower among children in the highest quintile of consumption. The intake of ‘extra’ foods was inversely associated with the intake of core foods.

Conclusions:  The high percentage of energy contributed by ‘extra’ foods and their negative association with nutrient density emphasise the need for dietary guidance for parents of children aged 1–2 years. These preliminary data on commonly consumed ‘extra’ foods and portion sizes may inform age-specific dietary assessment methods.

Effect of Na-chloride on the bioleaching of a chalcopyrite concentrate in shake flasks and stirred tank bioreactors

Oxidative dissolution of chalcopyrite at ambient temperatures is generally slow and subject to passivation, posing a major challenge for developing bioleaching applications for this recalcitrant mineral. Chloride is known to enhance the chemical leaching of chalcopyrite, but much of this effect has been demonstrated at elevated temperatures. This study was undertaken to test whether 100-200 mM Na-chloride enhances the chemical and bacterial leaching of chalcopyrite in shake flasks and stirred tank bioreactor conditions at mesophilic temperatures. Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and abiotic controls were employed for the leaching experiments. Addition of Na-chloride to the bioleaching suspension inhibited the formation of secondary phases from chalcopyrite and decreased the Fe(III) precipitation. Neither elemental S nor secondary Cu-sulfides were detected in solid residues by X-ray diffraction. Chalcopyrite leaching was enhanced when the solution contained bacteria, ferrous iron and Na-chloride under low redox potential (< 450 mV) conditions. Scanning electron micrographs and energy-dispersive analysis of X-rays revealed the presence of precipitates that were identified as brushite and jarosites in solid residues. Minor amounts of gypsum may also have been present. Electrochemical analysis of solid residues was in concurrence of the differential effects between chemical controls, chloride ions, and bacteria. Electrochemical impedance spectroscopy was used to characterize interfacial changes on chalcopyrite surface caused by different bioleaching conditions. In abiotic controls, the impedance signal stabilized after 28 days, indicating the lack of changes on mineral surface thereafter, but with more resistive behavior than chalcopyrite itself. For bioleached samples, the signal suggested some capacitive response with time owing to the formation of less conductive precipitates. At Bode-phase angle plots (middle frequency), a new time constant was observed that was associated with the formation of jarosite, possibly also with minor amount or elemental S, although this intermediate could not be verified by XRD. Real impedance vs. frequency plots indicated that the bioleaching continued to modify the chalcopyrite/solution interface even after 42 days. © 2013 The Authors.

Bacterial and chemical leaching of chalcopyrite concentrates as affected by the redox potential and ferric/ferrous iron ratio at 22 degrees C

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Magnetic Tuning of All-Organic Binary Alloys between Two Stable Radicals

Mixtures of 2-(4,5,6,7-tetrafluorobenzimidazol-2-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (F4BImNN) and 2-(benzi-midazol-2-yl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazole-3-oxide-1-oxyl (BImNN.) crystallize as solid solutions (alloys) across a wide range of binary compositions. (F4BImNN)(x)(BImNN)((1-x)) with x < 0.8 gives orthorhombic unit cells, while x >= 0.9 gives monoclinic unit cells. In all crystalline samples, the dominant intermolecular packing is controlled by one-dimensional (1D) hydrogen-bonded chains that lead to quasi-1D ferromagnetic behavior. Magnetic analysis over 0.4-300 K indicates ordering with strong 1D ferromagnetic exchange along the chains (J/k = 12-22 K). Interchain exchange is estimated to be 33- to 150-fold weaker, based on antiferromagnetic ordered phase formation below Neel temperatures in the 0.4-1.2 K range for the various compositions. The ordering temperatures of the orthorhombic samples increase linearly as (1 - x) increases from 0.25 to 1.00. The variation is attributed to increased interchain distance corresponding to decreased interchain exchange, when more F4BImNN is added into the orthorhombic lattice. The monoclinic samples are not part of the same trend, due to the different interchain arrangement associated with the phase change.