Studies on the reduction of hematite by carbon

Single pellet experiments have been carried out in a nitrogen atmosphere to study the reduction of hematite by graphite in the temperature range 925 to 1060°C. The effect of variables such as c/Fe2O3 molar ratio, pellet size, and so forth, has been investigated. Gas analysis data show a continuous decrease in CO2/CO ratio during reduction, the values being far away from Fe/FeO equilibrium for wustite reduction by CO. The activation energies associated with different degrees of reduction appear to be widely different suggesting a possible changeover in reaction mechanism during the progress of reduction. X-ray diffraction studies confirm the stepwise nature of hematite reduction.

Nucleotide sequence of the 3' terminal region of belladonna mottle virus-Iowa (renamed Physalis mottle virus) RNA and an analysis of the relationships of tymoviral coat proteins

The 3prime terminal 1255nt sequence of Physalis mottle virus (PhMV) genomic RNA has been determined from a set of overlapping cDNA clones. The open reading frame (ORF) at the 3prime terminus corresponds to the amino acid sequence of the coat protein (CP) determined earlier except for the absence of the dipeptide, Lys-Leu, at position 110-111. In addition, the sequence upstream of the CP gene contains the message coding for 178 amino acid residues of the C-terminus of the putative replicase protein (RP). The sequence downstream of the CP gene contains an untranslated region whose terminal 80 nucleotides can be folded into a characteristic tRNA-like structure. A phylogenetic tree constructed after aligning separately the sequence of the CP, the replicase protein (RP) and the tRNA-like structure determined in this study with the corresponding sequences of other tymoviruses shows that PhMV wrongly named belladonna mottle virus [BDMV(I)] is a separate tymovirus and not another strain of BDMV(E) as originally envisaged. The phylogenetic tree in all the three cases is identical showing that any subset of genomic sequence of sufficient length can be used for establishing evolutionary relationships among tymoviruses.

The politics of foreign aid: A median voter perspective

The paper presents a model where the median voter in the donor country determines the support of foreign aid. It is first established that an individual in the donor country is affected by the direct benefits (due to altruism) and costs (due to taxes) of giving aid, and by the indirect benefits or costs of a change in the terms of trade. Then it is shown that the latter effect works through changing both the donor country's average income and its distribution of income. Given the stylized facts of a capital-abundant donor country and relatively capital-poor median voter, it is shown how redistribution-of-income effects soften the impact of terms-of-trade changes on the political support for foreign aid.

The Consequences of Phenotypic Plasticity in Cyclically Varying Environments: A Genetic Algorithm Study

By “phenotypic plasticity” we refer to the capacity of a genotype to exhibit different phenotypes, whether in the same or in different environments. We have previously demonstrated that phenotypic plasticity can improve the degree of adaptation achieved via natural selection (Behera & Nanjundiah, 1995). That result was obtained from a genetic algorithm model of haploid genotypes (idealized as one-dimensional strings of genes) evolving in a fixed environment. Here, the dynamics of evolution is examined under conditions of a cyclically varying environment. We find that the rate of evolution, as well as the extent of adaptation (as measured by mean population fitness) is lowered because of environmental cycling. The decrease is adaptation caused by a varying environment can, however, be partly or wholly compensated by an increase in the degree of plasticity that a genotype is capable of. Also, the reduction of population fitness caused by a variable environment can be partially offset by decreasing the total number of genetic loci. We conjecture that an increase in genome size may have been among the factors responsible for the evolution of phenotypic plasticity.

A f/oxymoron? : Women, creativity and the suburbs

Donald Horne famously wrote, ‘Australia was born urban and quickly grew suburban’ (1964), an observation that carries a weight of assumptions about suburban living. Historically, the Australian suburbs have been regarded as places of retreat, family life and female activity, and subsequently as a place where not much of interest happens. By contrast, a city's central areas are seen as more dynamic spaces and, with recent creative city thinking and planning, as potential powerhouses of innovation and creativity. This article challenges assumptions about suburban living as passive places of retreat through an examination of women in the creative workforce who are living and working in the suburbs. It draws on historical accounts of creative suburban activity and a research project that mapped and investigated the experience of creative workers in the outer suburbs of Brisbane and Melbourne. The study finds that there is much creative work occurring in suburban localities, but this is not as unusual as might be expected.

An analytical model for performance evaluation of multimedia applications over EDCA in an IEEE 802.11e WLAN

We extend the modeling heuristic of (Harsha et al. 2006. In IEEE IWQoS 06, pp 178 - 187) to evaluate the performance of an IEEE 802.11e infrastructure network carrying packet telephone calls, streaming video sessions and TCP controlled file downloads, using Enhanced Distributed Channel Access (EDCA). We identify the time boundaries of activities on the channel (called channel slot boundaries) and derive a Markov Renewal Process of the contending nodes on these epochs. This is achieved by the use of attempt probabilities of the contending nodes as those obtained from the saturation fixed point analysis of (Ramaiyan et al. 2005. In Proceedings ACM Sigmetrics, `05. Journal version accepted for publication in IEEE TON). Regenerative analysis on this MRP yields the desired steady state performance measures. We then use the MRP model to develop an effective bandwidth approach for obtaining a bound on the size of the buffer required at the video queue of the AP, such that the streaming video packet loss probability is kept to less than 1%. The results obtained match well with simulations using the network simulator, ns-2. We find that, with the default IEEE 802.11e EDCA parameters for access categories AC 1, AC 2 and AC 3, the voice call capacity decreases if even one streaming video session and one TCP file download are initiated by some wireless station. Subsequently, reducing the voice calls increases the video downlink stream throughput by 0.38 Mbps and file download capacity by 0.14 Mbps, for every voice call (for the 11 Mbps PHY). We find that a buffer size of 75KB is sufficient to ensure that the video packet loss probability at the QAP is within 1%.

A direct borohydride fuel cell employing Prussian Blue as mediated electron-transfer hydrogen peroxide reduction catalyst

A direct borohydride-hydrogen peroxide fuel cell employing carbon-supported Prussian Blue (PB) as mediated electron-transfer cathode catalyst is reported. While operating at 30 °C, the direct borohydride-hydrogen peroxide fuel cell employing carbon-supported PB cathode catalyst shows superior performance with the maximum output power density of 68 mW cm−2 at an operating voltage of 1.1 V compared to direct borohydride-hydrogen peroxide fuel cell employing the conventional gold-based cathode with the maximum output power density of 47 mW cm−2 at an operating voltage of 0.7 V. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Analysis (EDAX) suggest that anchoring of Cetyl-Trimethyl Ammonium Bromide (CTAB) as a surfactant moiety on carbon-supported PB affects the catalyst morphology. Polarization studies on direct borohydride-hydrogen peroxide fuel cell with carbon-supported CTAB-anchored PB cathode exhibit better performance with the maximum output power density of 50 mW cm−2 at an operating voltage of 1 V than the direct borohydride-hydrogen peroxide fuel cell with carbon-supported Prussian Blue without CTAB with the maximum output power density of 29 mW cm−2 at an operating voltage of 1 V.

Individualized immunosuppression after renal transplantation in childhood

Pediatric renal transplantation (TX) has evolved greatly during the past few decades, and today TX is considered the standard care for children with end-stage renal disease. In Finland, 191 children had received renal transplants by October 2007, and 42% of them have already reached adulthood. Improvements in treatment of end-stage renal disease, surgical techniques, intensive care medicine, and in immunosuppressive therapy have paved the way to the current highly successful outcomes of pediatric transplantation. In children, the transplanted graft should last for decades, and normal growth and development should be guaranteed. These objectives set considerable requirements in optimizing and fine-tuning the post-operative therapy. Careful optimization of immunosuppressive therapy is crucial in protecting the graft against rejection, but also in protecting the patient against adverse effects of the medication. In the present study, the results of a retrospective investigation into individualized dosing of immunosuppresive medication, based on pharmacokinetic profiles, therapeutic drug monitoring, graft function and histology studies, and glucocorticoid biological activity determinations, are reported. Subgroups of a total of 178 patients, who received renal transplants in 1988 2006 were included in the study. The mean age at TX was 6.5 years, and approximately 26% of the patients were <2 years of age. The most common diagnosis leading to renal TX was congenital nephrosis of the Finnish type (NPHS1). Pediatric patients in Finland receive standard triple immunosuppression consisting of cyclosporine A (CsA), methylprednisolone (MP) and azathioprine (AZA) after renal TX. Optimal dosing of these agents is important to prevent rejections and preserve graft function in one hand, and to avoid the potentially serious adverse effects on the other hand. CsA has a narrow therapeutic window and individually variable pharmacokinetics. Therapeutic monitoring of CsA is, therefore, mandatory. Traditionally, CsA monitoring has been based on pre-dose trough levels (C0), but recent pharmacokinetic and clinical studies have revealed that the immunosuppressive effect may be related to diurnal CsA exposure and blood CsA concentration 0-4 hours after dosing. The two-hour post-dose concentration (C2) has proved a reliable surrogate marker of CsA exposure. Individual starting doses of CsA were analyzed in 65 patients. A recommended dose based on a pre-TX pharmacokinetic study was calculated for each patient by the pre-TX protocol. The predicted dose was clearly higher in the youngest children than in the older ones (22.9±10.4 and 10.5±5.1 mg/kg/d in patients <2 and >8 years of age, respectively). The actually administered oral doses of CsA were collected for three weeks after TX and compared to the pharmacokinetically predicted dose. After the TX, dosing of CsA was adjusted according to clinical parameters and blood CsA trough concentration. The pharmacokinetically predicted dose and patient age were the two significant parameters explaining post-TX doses of CsA. Accordingly, young children received significantly higher oral doses of CsA than the older ones. The correlation to the actually administered doses after TX was best in those patients, who had a predicted dose clearly higher or lower (> ±25%) than the average in their age-group. Due to the great individual variation in pharmacokinetics standardized dosing of CsA (based on body mass or surface area) may not be adequate. Pre-Tx profiles are helpful in determining suitable initial CsA doses. CsA monitoring based on trough and C2 concentrations was analyzed in 47 patients, who received renal transplants in 2001 2006. C0, C2 and experienced acute rejections were collected during the post-TX hospitalization, and also three months after TX when the first protocol core biopsy was obtained. The patients who remained rejection free had slightly higher C2 concentrations, especially very early after TX. However, after the first two weeks also the trough level was higher in the rejection-free patients than in those with acute rejections. Three months after TX the trough level was higher in patients with normal histology than in those with rejection changes in the routine biopsy. Monitoring of both the trough level and C2 may thus be warranted to guarantee sufficient peak concentration and baseline immunosuppression on one hand and to avoid over-exposure on the other hand. Controlling of rejection in the early months after transplantation is crucial as it may contribute to the development of long-term allograft nephropathy. Recently, it has become evident that immunoactivation fulfilling the histological criteria of acute rejection is possible in a well functioning graft with no clinical sings or laboratory perturbations. The influence of treatment of subclinical rejection, diagnosed in 3-month protocol biopsy, to graft function and histology 18 months after TX was analyzed in 22 patients and compared to 35 historical control patients. The incidence of subclinical rejection at three months was 43%, and the patients received a standard rejection treatment (a course of increased MP) and/or increased baseline immunosuppression, depending on the severity of rejection and graft function. Glomerular filtration rate (GFR) at 18 months was significantly better in the patients who were screened and treated for subclinical rejection in comparison to the historical patients (86.7±22.5 vs. 67.9±31.9 ml/min/1.73m2, respectively). The improvement was most remarkable in the youngest (<2 years) age group (94.1±11.0 vs. 67.9±26.8 ml/min/1.73m2). Histological findings of chronic allograft nephropathy were also more common in the historical patients in the 18-month protocol biopsy. All pediatric renal TX patients receive MP as a part of the baseline immunosuppression. Although the maintenance dose of MP is very low in the majority of the patients, the well-known steroid-related adverse affects are not uncommon. It has been shown in a previous study in Finnish pediatric TX patients that steroid exposure, measured as area under concentration-time curve (AUC), rather than the dose correlates with the adverse effects. In the present study, MP AUC was measured in sixteen stable maintenance patients, and a correlation with excess weight gain during 12 months after TX as well as with height deficit was found. A novel bioassay measuring the activation of glucocorticoid receptor dependent transcription cascade was also employed to assess the biological effect of MP. Glucocorticoid bioactivity was found to be related to the adverse effects, although the relationship was not as apparent as that with serum MP concentration. The findings in this study support individualized monitoring and adjustment of immunosuppression based on pharmacokinetics, graft function and histology. Pharmacokinetic profiles are helpful in estimating drug exposure and thus identifying the patients who might be at risk for excessive or insufficient immunosuppression. Individualized doses and monitoring of blood concentrations should definitely be employed with CsA, but possibly also with steroids. As an alternative to complete steroid withdrawal, individualized dosing based on drug exposure monitoring might help in avoiding the adverse effects. Early screening and treatment of subclinical immunoactivation is beneficial as it improves the prospects of good long-term graft function.

Expression of hyoscyamine 6 beta-hydroxylase in the root pericycle cells and accumulation of its product scopolamine in leaf and stem tissues of Datura metel L.

Hyoscyamine 60-hydroxylase (H6H: EC 1.14.11.11), a key enzyme at the terminal step of tropane alkaloid biosynthesis, converts hyoscyamine to scopolamine. The accumulation of scopolamine in different organs, in particular the aerial parts for storage, is subject to the expression of hyoscyamine 6-phydroxylase as well as its transport from the site of synthesis. To understand the molecular basis of this regulation, we have analyzed, in parallel, the relative levels of hyoscyamine and scopolamine, and the accumulation of H6H (both protein and transcript) in leaves, stems and roots of D. metel. The root, stem and leaf tissues all contain about 0.51-0.65 mg g(-1) dry weight of scopolamine. Hyoscyamine content was extremely low in leaf and stem tissues and was about 0.28 mg g(-1) dry weight in the root tissue. H6H protein and its transcript were found only in roots but not in the aerial parts viz. stems and leaves. The immunolocalization studies performed on leaf, stem, root as well as hairy root tissues showed that H6H was present only in the pericycle cells of young lateral and hairy roots. These studies suggest that the conversion of hyoscyamine to scopolamine takes place in the root pericycle cells, and the alkaloid biosynthesized in the roots gets translocated to the aerial parts in D. metel. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Is economic valuation of ecosystem services useful to decision-makers? Lessons learned from Australian coastal and marine management

Economic valuation of ecosystem services is widely advocated as a useful decision-support tool for ecosystem management. However, the extent to which economic valuation of ecosystem services is actually used or considered useful in decision-making is poorly documented. This literature blindspot is explored with an application to coastal and marine ecosystems management in Australia. Based on a nation-wide survey of eighty-eight decision-makers representing a diversity of management organizations, the perceived usefulness and level of use of ecosystem services economic valuation in support of coastal and marine management are examined. A large majority of decision-makers are found to be familiar with economic valuation and consider it useful - even necessary - in decision-making, although this varies across decision-makers groups. However, most decision-makers never or rarely use it. The perceived level of importance and trust in estimated dollar values differ across ecosystem services, and are especially high for values that relate to commercial activities. A number of factors are also found to influence respondent’s use of economic valuation. Such findings concur with conclusions from other existing works, and are instructive to reflect on the issue of the usefulness of ESV in environmental management decision-making. They also confirm that the survey-based approach developed in this application represents a sound strategy to examine this issue at various scales and management levels.

Buckling of clamped skew plates

IN this Note, a condensed version of Ref. 1, only the results are presented. The available results for buckling of clamped skew plates are few and far from complete.2'3 In the present investigation, results for several new plate configurations and loading conditions as well as more accurate results for configurations reported in previous literature are obtained.In general, for a given a/b, the critical values increase with increasing skew angle. The results also confirm the conjecture of Ref. 4 that in the case of buckling under shear (Nxv)> "two critical values exist, the positive shear (one tending to reduce the skew angle) being numerically greater than the negative shear. However, reliable values for positive shear could not be obtained in Ref. 4 because of convergence difficulties.

Pajala–Kolarin ja Soklin kaivosten rata-, satama- ja meriväyläinvestointien sekä kaivosten toiminnan vaikutukset valtion ja kuntien verotuloihin

Tutkimuksen tavoitteena oli arvioida Pajala–Kolarin ja Soklin kaivosten rata-, tie-, satama- ja meriväyläinvestointien sekä kaivosten toiminnan vaikutuksia valtion verojen ja veronluonteisten maksujen kertymiin. Lisäksi tarkasteltiin vaikutuksia Kolarin ja Pajalan kuntien sekä Soklin kaivoksen läheisten Itä- ja Pohjois-Lapin kuntaryhmien verokertymiin. Laskelmat suoritettiin yleisen tasapainon (CGE) RegFinDyn -aluemallilla vuosille 2008–2020. Pajala–Kolarin kaivos toisi valtiolle yhteensä 374,0 miljoonaa euroa verojen ja veronluonteisten maksujen lisäkertymää. Suomen osuus lisäkertymästä olisi 206,1 (55,1 %) ja Ruotsin 167,9 (44,9 %) miljoonaa euroa. Valtio saisi väyläinvestointiensa kokonaiskustannukset takaisin noin vuonna 2022 eli 15 vuodessa, vaikkei Ruotsi osallistuisi rahoitukseen. Kolarin kunnan verokertymä kasvaisi vuosina 2011–2014 yhteensä 66 %:lla ja vuodesta 2017 lähtien 12 %:lla vuoteen 2012 verrattuna. Pajalan kunnan verokertymä kasvaisi vastaavina vuosina yhteensä 97 %:lla ja vuodesta 2017 lähtien 15 %:lla vuoteen 2011 verrattuna. Soklin kaivos toisi valtiolle yhteensä 178,9 miljoonaa euroa verojen ja veronluonteisten maksujen lisäkertymää. Valtio saisi väyläinvestointiensa kokonaiskustannukset takaisin noin vuonna 2030 eli 21 vuodessa. Kaivoksen läheisen seitsemän kunnan ryhmän verokertymä kasvaisi vuosina 2011-2014 yhteensä 30 %:lla ja vuodesta 2019 lähtien 1 %:lla vuoteen 2007 verrattuna.

Hirsitaloteollisuuden kehityshaasteet

Pientalobarometri 2/2008 ennustaa omakotitalorakentamisen jatkavan laskuaan rakentamiskustannusten kasvamisesta, kaavoituksesta, tonttitarjonnasta ja talouden tilasta johtuen. Kustannusten odotetaan edelleen nousevan mm. energia­tehokkuuden kohentumisen myötä. Työ- ja elinkeinoministeriön Puutalojen ja rakennuspuusepäntuotteiden valmistus –toimialaraportissa 2008 oletetaan myös, että lämmöneristysvaatimukset ovat saattaneet lisätä massiivihirsitalojen kysyntää, koska uusien määräysten voimaantulon jälkeen niitä ei mahdollisesti enää tehdä. Kehityksen voidaan olettaa johtavan rakennusten koon ja varustetason järkevöittämiseen. Oma­koti­talorakentamisen tarpeeksi pientalobarometri laskee 20 000 asuntoaloitusta, mutta toimialaraportissa määrän arvioidaan vuonna 2008 jäävän 12 500 oma­kotitalon aloitukseen. Avaimet käteen –rakentaminen on kasvusuunnassa ja talo­paketit ovat kehittymässä selvemmiksi rakennusosakokonaisuuksiksi. Pientalobarometri kertoo suomalaisten toivovan yksilöllisyyttä. Talotehtaiden toimituksista yksilöllisiä suunnitteluratkaisuja on kolmannes ja tyyppimuunnoksia puolet. Valmisosatalojen osuus asunnoista on noin 68 % ja teollisen hirren osuus valmisosatalojen markkinoista on nyt kutakuinkin samoissa 10 % lukemissa kuin 20 vuotta sitten. Korkeimmillaan teollisen hirren osuus valmisosataloista kävi 17 % tasolla kymmenen vuotta sitten, vuosina 1995 ja 1996. Siporex-, betoni,- tiili- ja harkkotalojen osuus on noussut kahdessakymmenessä vuodessa 4 %:sta 12 %:iin ja precut-talojen osuus 2 %:sta 16 %:iin, kun taas puuelementtien osuus on laskenut 85 %:sta 62 %:iin. Talopaketin keskimääräinen kuluttajahinta on Toimialaraportin mukaan noin 83 000 euroa ja niitä valmistuu vuodessa alle 10 000. Talopakettimarkkinat ovat Pientalobarometrin mukaan vuonna 2008 hieman laskeneet vuosien 2006 ja 2007 huippulukemista alle 800 miljoonan euron. Teollisten hirsivalmistajien liikevaihto laski myös vuodesta 2007 alle 350 miljoonan. Toimialaraportin mukaan puutalojen valmistus työllistää vajaa 4000 henkeä 251 toimipaikassa (2006). Alan liikevaihto vuonna 2006 oli 812 miljoonaa euroa ja viennin arvo 178 miljoonaa euroa. Viennin kasvun todettiin riippuvan hirsitaloteollisuudesta. Viennin kannalta tärkeitä alueita ovat Keski-Eurooppa, Venäjä, Japani ja Pohjoismaat. Puutalojen vienti on Toimialaraportin mukaan kohonnut 90-luvun alun noin 30 miljoonasta yli 200 miljoonaan euroon, josta hirsitalojen viennin arvo ylittää 160 miljoonaa. Tutkimus- ja kehittämiskuluiksi arvioidaan puutalon valmistajilla 0–2 % tuotannon arvosta. Puutalojen mediaanikäyttökate oli Toimialaraportin mukaan vuonna 2006 noin 6 % kun teollisuuden vastaava luku on 10 %. Finnveran tilastointi hirsitalojen kustannusrakenteesta ja kannattavuudesta ei poikkea tästä, vaan hirsitalojen käyttökatteeksi ilmoitetaan 6,4 % ja kokonaistulokseksi 3,4 % vuonna 2007. Toimialaraportin mukaan teollisuuden omavaraisuusaste on noin 43 % kun taas puutaloteollisuuden omavaraisuusaste jää 26,5 %:iin ja hirsitalojen Finnveran mukaan 27,7 %:iin. Hirsitaloja valmistaa Toimialaraportin mukaan noin 150 yritystä. Alan kahden suurimman yrityksen osuus on lähes puolet koko alan liikevaihdosta.