105 research outputs found

    E-procurement in Public Organization

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    Tampereen kaupungin kokonaishankinnoista vain kaksi prosenttia tehtiin toiminnanohjausjÀrjestelmÀllÀ vuonna 2013. JÀrjestelmÀn matalasta kÀyttöasteesta johtuen hankintatiedot puuttuvat jÀrjestelmÀstÀ, mikÀ hankaloittaa hankintojen strategista johtamista. Työn taustalla on tarve tehostaa toimintoja ja saada aikaan kustannussÀÀstöjÀ sekÀ saada hankinnoista enemmÀn tietoa niiden tehokkaammaksi johtamiseksi. Tutkimuksen tarkoituksena oli tunnistaa keinoja, joiden avulla Tampereen kaupungin ostamista voidaan kehittÀÀ sÀhköisellÀ ostojÀrjestelmÀllÀ. PÀÀtavoitteena oli kaupungin ostamisen nykytilan selvittÀminen ja siihen soveltuvan sÀhköisen ratkaisun vaatimusten mÀÀrittely. TÀssÀ työssÀ keskityttiin työn toimeksiantajan Tampereen Logistiikan valitsemien Tampereen kaupungin yksiköiden Infran, Kotihoidon ja Tilakeskuksen ostamisen kehittÀmiseen. Tutkimus toteutettiin laadullisena monimenetelmÀisenÀ tapaustutkimuksena. Aineistona kÀytettiin kirjallisuutta, vanhoja Tampereen kaupungin selvityksiÀ sekÀ kohdeyksiköiden ja muiden kaupunkien hankinnoista vastaavien henkilöiden haastatteluja. Aikaisempi kirjallisuus on kÀsitellyt ostamisen suhdetta hankintoihin ja toimitusketjuun sekÀ tarkastellut sÀhköistÀ ostamista keinona tehostaa hankintoja. Tutkimuksen empiriaosuus esittelee ensin havaintoja aikaisemmista tutkimuksista sekÀ muiden kaupunkien benchmark-analyysistÀ. Toisessa osassa kÀsitellÀÀn ostotoimintaa ja sen kehitysmahdollisuuksia kohdeorganisaation valikoiduissa yksiköissÀ. Aineistoanalyysin tuloksena tunnistettiin ostamisen ongelmaksi kirjavat ostoprosessit sekÀ niistÀ aiheutuvat prosessikustannukset. Tuloksina saatiin ostamisen asettamia vaatimuksia ostojÀrjestelmÀlle, joita ovat noutojen kirjaus ja mobiilikÀyttömahdollisuus. Ratkaisuehdotuksena annettiin malli uudesta prosessista, johon sitoutuu vÀhemmÀn työaikaa aikaisempaan verrattuna sekÀ ehdotettiin katalogien kÀyttöönottamista kaupungin omassa jÀrjestelmÀssÀ

    Molecular Epidemiology and Evolution of Human Respiratory Syncytial Virus and Human Metapneumovirus

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    Human respiratory syncytial virus (HRSV) and human metapneumovirus (HMPV) are ubiquitous respiratory pathogens of the Pneumovirinae subfamily of the Paramyxoviridae. Two major surface antigens are expressed by both viruses; the highly conserved fusion (F) protein, and the extremely diverse attachment (G) glycoprotein. Both viruses comprise two genetic groups, A and B. Circulation frequencies of the two genetic groups fluctuate for both viruses, giving rise to frequently observed switching of the predominantly circulating group. Nucleotide sequence data for the F and G gene regions of HRSV and HMPV variants from the UK, the Netherlands, Bangkok and data available from Genbank were used to identify clades of both viruses. Several contemporary circulating clades of HRSV and HMPV were identified by phylogenetic reconstructions. The molecular epidemiology and evolutionary dynamics of clades were modelled in parallel. Times of origin were determined and positively selected sites were identified. Sustained circulation of contemporary clades of both viruses for decades and their global dissemination demonstrated that switching of the predominant genetic group did not arise through the emergence of novel lineages each respiratory season, but through the fluctuating circulation frequencies of pre-existing lineages which undergo proliferative and eclipse phases. An abundance of sites were identified as positively selected within the G protein but not the F protein of both viruses. For HRSV, these were discordant with previously identified residues under selection, suggesting the virus can evade immune responses by generating diversity at multiple sites within linear epitopes. For both viruses, different sites were identified as positively selected between genetic groups

    Allosteric Modulation of the HIV-1 gp120-gp41 Association Site by Adjacent gp120 Variable Region 1 (V1) N-Glycans Linked to Neutralization Sensitivity

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    The HIV-1 gp120-gp41 complex, which mediates viral fusion and cellular entry, undergoes rapid evolution within its external glycan shield to enable escape from neutralizing antibody (NAb). Understanding how conserved protein determinants retain functionality in the context of such evolution is important for their evaluation and exploitation as potential drug and/ or vaccine targets. In this study, we examined how the conserved gp120-gp41 association site, formed by the N- and Cterminal segments of gp120 and the disulfide-bonded region (DSR) of gp41, adapts to glycan changes that are linked to neutralization sensitivity. To this end, a DSR mutant virus (K601D) with defective gp120-association was sequentially passaged in peripheral blood mononuclear cells to select suppressor mutations. We reasoned that the locations of suppressors point to structural elements that are functionally linked to the gp120-gp41 association site. In culture 1, gp120 association and viral replication was restored by loss of the conserved glycan at Asn136 in V1 (T138N mutation) inconjunction with the L494I substitution in C5 within the association site. In culture 2, replication was restored with deletion of the N139INN sequence, which ablates the overlapping Asn141-Asn142-Ser-Ser potential N-linked glycosylation sequons inV1, in conjunction with D601N in the DSR. The 136 and 142 glycan mutations appeared to exert their suppressive effects by altering the dependence of gp120-gp41 interactions on the DSR residues, Leu593, Trp596 and Lys601. The 136 and/or 142glycan mutations increased the sensitivity of HIV-1 pseudovirions to the glycan-dependent NAbs 2G12 and PG16, and also pooled IgG obtained from HIV-1-infected individuals. Thus adjacent V1 glycans allosterically modulate the distal gp120-gp41 association site. We propose that this represents a mechanism for functional adaptation of the gp120-gp41 association site to an evolving glycan shield in a setting of NAb selection

    Forty years of carabid beetle research in Europe - from taxonomy, biology, ecology and population studies to bioindication, habitat assessment and conservation

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    Volume: 100Start Page: 55End Page: 14

    Prime-boost immunization of rabbits with HIV-1 gp120 elicits potent neutralization activity against a primary viral isolate

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    <div><p>Development of a vaccine for HIV-1 requires a detailed understanding of the neutralizing antibody responses that can be experimentally elicited to difficult-to-neutralize primary isolates. Rabbits were immunized with the gp120 subunit of HIV-1 JR-CSF envelope (Env) using a DNA-prime protein-boost regimen. We analyzed five sera that showed potent autologous neutralizing activity (IC50s at ∌10<sup>3</sup> to 10<sup>4</sup> serum dilution) against pseudoviruses containing Env from the primary isolate JR-CSF but not from the related isolate JR-FL. Pseudoviruses were created by exchanging each variable and constant domain of JR-CSF gp120 with that of JR-FL or with mutations in putative N-glycosylation sites. The sera contained different neutralizing activities dependent on C3 and V5, C3 and V4, or V4 regions located on the glycan-rich outer domain of gp120. All sera showed enhanced neutralizing activity toward an Env variant that lacked a glycosylation site in V4. The JR-CSF gp120 epitopes recognized by the sera are generally distinct from those of several well characterized mAbs (targeting conserved sites on Env) or other type-specific responses (targeting V1, V2, or V3 variable regions). The activity of one serum requires specific glycans that are also important for 2G12 neutralization and this serum blocked the binding of 2G12 to gp120. Our findings show that different fine specificities can achieve potent neutralization of HIV-1, yet this strong activity does not result in improved breadth.</p> </div

    HIV-1 escapes from N332-directed antibody neutralization in an elite neutralizer by envelope glycoprotein elongation and introduction of unusual disulfide bonds

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