323 resultados para HX-projekti


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Lähtökohtaisesti projekti nähdään lyhyen aikavälin toimintana. Projekteilla on kuitenkin sekä strateginen että taktinen ulottuvuus. Projektiorientoituneessa organisaatiossa projektijohtaminen on sulautettu osaksi organisaation johtamisjärjestelmää. Äärimmilleen vietynä johtaminen projekteilla (engl. management by projects) tarkoittaa, että yrityksen kaikki toiminnot tuotetaan projektien kautta linjaorganisaation hallinnoidessa projektisalkkua. Linja- ja projektiorganisaation rajapinnassa projektijohdolla on oma roolinsa projektin ja linjaorganisaation välisten suhteiden hoitamisessa ja projektin onnistumisessa. Projektijohdon strategisen aseman myötä heidän roolinsa laajenee taktisesta johtamisesta strategiseen johtamiseen ja tätä kautta kilpailuetuun. Projektijohdon mahdollisuuksia osallistua kilpailuedun kehittämiseen on kuitenkin tutkittu verrattain vähän. Projektiorientoituneen organisaation malli pyrkii vastaamaan muuttuvan ympäristön luomiin haasteisiin. Staattisen kilpailuedun tarkastelusta tulisikin siirtyä lyhytaikaisten kilpailuetujen hyödyntämiseen, mikä voidaan tehdä esimerkiksi projekteissa. Tämän tutkimuksen pääongelma oli, millaisena projektijohto kokee strategisen mahdollisuutensa osallistua projektiorientoituneen organisaation pitkän aikavälin kilpailuedun kehittämiseen. Tutkimus toteutettiin kvalitatiivisena tapaustutkimuksena, jonka empiria kerättiin haastattelemalla seitsemää projektijohdon edustajaa viidestä eri yrityksestä ja eri toimialoilta. Tutkimuksen tuloksissa korostui empirian ja alan kirjallisuuden yhdenmukaisuus siinä, että projektijohto ja erityisesti projektipäälliköt näkevät oman roolinsa taktisena. Heidän työtään määritteli yksittäisen projektin johtaminen. Itse projektiorganisaation osalta koettiin kuitenkin tarpeelliseksi mahdollisuus osallistua linjaorganisaation pitkän aikavälin toiminnan kehittämiseen. Kilpailuedun kehittämiseen osallistumisen mahdollisuudet koettiin vaihtelevasti sekä hyviksi että kehnoiksi. Strategisten projektien ohella projektijohto pystyi kehittämään linjaorganisaation kilpailuetua epäsuorasti. Organisatoristen tekijöiden ohella projektijohdon strategista asemaa määrittelee se, minkälaisena henkilö itse kokee asemansa. Tämän tutkimuksen tulosten perusteella projektijohdon strategisia mahdollisuuksia hyödynnettiin puutteellisesti. Esimerkiksi tietoperusteista kilpailuetua kehitettäessä projektijohdon osaamista voitaisiin hyödyntää enemmän henkilöstö- ja kompetenssijohtamisessa. Jotta projektiorientoituneen organisaation malli voisi toimia puhtaasti ja jotta projektijohto voisi paremmin osallistua linjaorganisaation pitkän aikavälin tavoitteiden, kuten kilpailuedun, kehittämiseen, näyttäisi tämän tutkimuksen perusteella siltä, että projektijohdolla tulisi olla sama hierarkkinen asema kuin linjajohdolla.

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The magnetic properties and interactions between transition metal (TM) impurities and clusters in low-dimensional metallic hosts are studied using a first principles theoretical method. In the first part of this work, the effect of magnetic order in 3d-5d systems is addressed from the perspective of its influence on the enhancement of the magnetic anisotropy energy (MAE). In the second part, the possibility of using external electric fields (EFs) to control the magnetic properties and interactions between nanoparticles deposited at noble metal surfaces is investigated. The influence of 3d composition and magnetic order on the spin polarization of the substrate and its consequences on the MAE are analyzed for the case of 3d impurities in one- and two-dimensional polarizable hosts. It is shown that the MAE and easy- axis of monoatomic free standing 3d-Pt wires is mainly determined by the atomic spin-orbit (SO) coupling contributions. The competition between ferromagnetic (FM) and antiferromagnetic (AF) order in FePtn wires is studied in detail for n=1-4 as a function of the relative position between Fe atoms. Our results show an oscillatory behavior of the magnetic polarization of Pt atoms as a function of their distance from the magnetic impurities, which can be correlated to a long-ranged magnetic coupling of the Fe atoms. Exceptionally large variations of the induced spin and orbital moments at the Pt atoms are found as a function of concentration and magnetic order. Along with a violation of the third Hund’s rule at the Fe sites, these variations result in a non trivial behavior of the MAE. In the case of TM impurities and dimers at the Cu(111), the effects of surface charging and applied EFs on the magnetic properties and substrate-mediated magnetic interactions have been investigated. The modifications of the surface electronic structure, impurity local moments and magnetic exchange coupling as a result of the EF-induced metallic screening and charge rearrangements are analysed. In a first study, the properties of surface substitutional Co and Fe impurities are investigated as a function of the external charge per surface atom q. At large inter-impurity distances the effective magnetic exchange coupling ∆E between impurities shows RKKY-like oscillations as a function of the distance which are not significantly affected by the considered values of q. For distances r < 10 Å, important modifications in the magnitude of ∆E, involving changes from FM to AF coupling, are found depending non-monotonously on the value and polarity of q. The interaction energies are analysed from a local perspective. In a second study, the interplay between external EF effects, internal magnetic order and substrate-mediated magnetic coupling has been investigated for Mn dimers on Cu(111). Our calculations show that EF (∼ 1eV/Å) can induce a switching from AF to FM ground-state magnetic order within single Mn dimers. The relative coupling between a pair of dimers also shows RKKY-like oscillations as a function of the inter-dimer distance. Their effective magnetic exchange interaction is found to depend significantly on the magnetic order within the Mn dimers and on their relative orientation on the surface. The dependence of the substrate-mediated interaction on the magnetic state of the dimers is qualitatively explained in terms of the differences in the scattering of surface electrons. At short inter-dimer distances, the ground-state configuration is determined by an interplay between exchange interactions and EF effects. These results demonstrate that external surface charging and applied EFs offer remarkable possibilities of manipulating the sign and strength of the magnetic coupling of surface supported nanoparticles.

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RESUMEN Introducción: El EQ-5D-Y proxy es un cuestionario genérico, de fácil comprensión y aplicación, que evalúa distintas dimensiones de la salud percibida. El objetivo del siguiente estudio fue describir por autoreporte la calidad de vida relacionada con la salud (CVRS) en una población escolar de Bogotá, Colombia, pertenecientes al estudio FUPRECOL. Métodos: Estudio descriptivo y transversal, realizado en 3.245 niños y 3.354 adolescentes, entre 9 y 17.9 años de edad, de 24 instituciones educativas oficiales de Bogotá, Colombia. Se aplicó de manera auto-administrada la versión validada al castellano por Olivares et al. (2009) del instrumento de CVRS infantil EQ-5D-Y proxy. Se analizaron los datos por medidas de tendencia central y se realizó una comparación de los observados en Colombia con estudios internacionales. Resultados: De la población evaluada, el 58,3% (n=3.848), fueron mujeres. En general, se observa puntuaciones elevadas en la CVRS en niños y adolescentes de ambos sexos. Al comparar por género, las dimensiones del EQ-5D-Y proxy “sentirse triste/preocupado o infeliz” y “tener dolor/malestar”, presentaron la mayor frecuencia de repuesta en el grupo de las mujeres. Al comparar los resultados de este estudio, por grupos de edad, con trabajos internacionales de niños y adolescentes, se observa que las puntuaciones del EQ-5D-Y proxy fueron superiores a los reportados en Suráfrica, Alemania e Italia. Conclusión: Se presentan valores de la CVRS según edad y sexo que podrán ser usados en la evaluación de la salud percibida en el ámbito escolar. Se hace necesario evaluar las propiedades psicométricas del EQ-5D-Y proxy en población Colombiana.

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The novel dioxatetraaza macrocycle [26]phen(2)N(4)O(2), which incorporates two phenanthroline units, has been synthesized, and its acid-base behavior has been evaluated by potentiometric and H-1 NMR methods. Six protonation constants were determined, and the protonation sequence was established by NMR. The location of the fifth proton on the phen nitrogen was confirmed by X-ray determinations of the crystal structures of the receptor as bromide and chloride salts. The two compounds have the general molecular formula {(H-5[26]phen(2)N(4)O(2))X-n(H2O)(5-n)}X(n-1)(.)mH(2)O, where X = Cl, n = 3, and m = 6 or X = Br, n = 4, and m = 5.5. In the solid state, the (H-5[26]phen(2)N(4)O(2))(5+) cation adopts a "horseshoe" topology with sufficient room to encapsulate three or four halogen anions through the several N-(HX)-X-... hydrogen-bonding interactions. Two supermolecules {(H-5[26]phen(2)N(4)O(2))X-n(H2O)(5-n)}((5-n)+) form an interpenetrating dimeric species, which was also found by ESI mass spectrum. Binding studies of the protonated macrocycle with aliphatic (ox(2-), mal(2-), suc(2-), cit(3-), cta(3-)) and aromatic (bzc(-), naphc(-), anthc(-), pyrc(-), ph(2-), iph(2-), tph(2-), btc(3-)) anions were determined in water by potentiometric methods. These studies were complemented by H-1 NMR titrations in D2O of the receptor with selected anions. The H-i[26]phen(2)N(4)O(2)(i+) receptor can selectively uptake highly charged or extended aromatic carboxylate anions, such as btc(3-) and pyrc(-), in the pH ranges of 4.0-8.5 and < 4.0, respectively, from aqueous solution that contain the remaining anions as pollutants or contaminants. To obtain further insight into these structural and experimental findings, molecular dynamics (MD) simulations were carried out in water solution.

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In the Eplerenone Post-Acute Myocardial Infarction Heart Failure Efficacy and Survival Study ( n = 6632), eplerenone- associated reduction in all- cause mortality was significantly greater in those with a history of hypertension ( Hx- HTN). There were 4007 patients with Hx- HTN ( eplerenone: n = 1983) and 2625 patients without Hx- HTN ( eplerenone: n = 1336). Propensity scores for eplerenone use, separately calculated for patients with and without Hx- HTN, were used to assemble matched cohorts of 1838 and 1176 pairs of patients. In patients with Hx- HTN, all- cause mortality occurred in 18% of patients treated with placebo ( rate, 1430/ 10 000 person- years) and 14% of patients treated with eplerenone ( rate, 1058/ 10 000 person- years) during 2350 and 2457 years of follow- up, respectively ( hazard ratio [ HR]: 0.71; 95% CI: 0.59 to 0.85; P < 0.0001). Composite end point of cardiovascular hospitalization or cardiovascular mortality occurred in 33% of placebo-treated patients ( 3029/ 10 000 person- years) and 28% of eplerenone- treated patients (2438/10 000 person- years) with Hx- HTN ( HR: 0.82; 95% CI: 0.72 to 0.94; P = 0.003). In patients without Hx- HTN, eplerenone reduced heart failure hospitalization ( HR: 73; 95% CI: 0.55 to 0.97; P = 0.028) but had no effect on mortality ( HR: 0.91; 95% CI: 0.72 to 1.15; P = 0.435) or on the composite end point ( HR: 0.91; 95% CI: 0.76 to 1.10; P = 0.331). Eplerenone should, therefore, be prescribed to all of the post - acute myocardial infarction patients with reduced left ventricular ejection fraction and heart failure regardless of Hx- HTN.

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In this paper by using the Poincare compactification in R(3) make a global analysis of the Rabinovich system(x) over dot = hy - v(1)x + yz, (y) over dot = hx - v(2)y - xz, (z) over dot = -v(3)z + xy,with (x, y, z) is an element of R(3) and ( h, v(1), v(2), v(3)) is an element of R(4). We give the complete description of its dynamics on the sphere at infinity. For ten sets of the parameter values the system has either first integrals or invariants. For these ten sets we provide the global phase portrait of the Rabinovich system in the Poincare ball (i.e. in the compactification of R(3) with the sphere S(2) of the infinity). We prove that for convenient values of the parameters the system has two families of singularly degenerate heteroclinic cycles. Then changing slightly the parameters we numerically found a four wings butterfly shaped strange attractor.

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The immunological response includes wide contexts involving several cells, and the macrophage is crucial in the cellular immune response. Several stimuli to macrophage membrane may induce the liberation of H2O2, contributing to antibacterial and cytotoxicical actions. Nowadays, there is a tendency to study natural products to verify their capacity of acting in the immune system. This study evaluated the citotoxicity of the bulk extract and the hexanic and acetic fractions extracted from Styrax camporum Pohl (Styracaceae) and the production of H2O2, on murine peritonal macrophages cultures exposed to fractions extracted from this plant. The results showed that the fraction HX 2 mg/ml produced the liberation of H 2O2 in high concentrations and to 4 mg/ml was observed high citotoxicity. The fractions AC did not produce the liberation of H 2O2 and EB was produced in low levels. We conclude that this HX is a potent stimulator of macrophage.

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Pós-graduação em Agronomia (Agricultura) - FCA

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Pós-graduação em Agronomia (Irrigação e Drenagem) - FCA

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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ABSTRACT: The present study investigated the prevalence of mutations in the -550 (H/L) and -221 (X/Y) mannose-binding lectin (MBL) gene promoter regions and their impact on infection by human immunodeficiency virus 1 (HIV-1) in a population of 128 HIV-1 seropositive and 97 seronegative patients. The allele identification was performed through the sequence-specific primer polymerase chain reaction method, using primer sequences specific to each polymorphism. The evolution of the infection was evaluated through CD4+ T-lymphocyte counts and plasma viral load. The allele and haplotype frequencies among HIV-1-infected patients and seronegative healthy control patients did not show significant differences. CD4+ T-lymphocyte counts showed lower levels among seropositive patients carrying haplotypes LY, LX and HX, as compared to those carrying the HY haplotype. Mean plasma viral load was higher among seropositive patients with haplotypes LY, LX and HX than among those carrying the HY haplotype. When promoter and exon 1 mutations were matched, it was possible to identify a significantly higher viral load among HIV-1 infected individuals carrying haplotypes correlated to low serum levels of MBL. The current study shows that haplotypes related to medium and low MBL serum levels might directly influence the evolution of viral progression in patients. Therefore, it is suggested that the identification of haplotypes within the promoter region of the MBL gene among HIV-1 infected persons should be further evaluated as a prognostic tool for AIDS progression.

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Um emergente interesse à MBL tem surgido, devido a sua importância no sistema imune inato. Recentes estudos relatam uma influência do polimorfismo na região promotora nas regiões -550 (H/L) e -221 (X/Y) do gene MBL, com a deficiência do sistema imune à determinados patógenos. O objetivo do presente estudo é investigar a associação entre o polimorfismo na região promotora do gene MBL e a infecção pelo HIV-1e a progressão à SIDA/AIDS. No estudo foi feita identificação destes alelos em uma população de 127 pacientes soropositivos para HIV-1 e em 97 indivíduos soronegativos, a partir da técnica de SSP-PCR, utilizando-se seqüências de iniciadores específicos para cada variante. A evolução da infecção nos pacientes soropositivos foi avaliada por meio da contagem de linfócito T CD4+ e da carga viral plasmática. As distribuições nas freqüências alélicas e haplotípicas entre os grupos de portadores do HIV-1 e nos controles soronegativos não apresentaram diferenças estatisticamente significantes (p>0,05). Entretanto, pacientes soropostivos portadores do haplótipo HY apresentaram uma maior contagem e uma evolução significativa no número de linfócitos T CD4+; e uma menor contagem e maior redução da carga viral plasmática, em relação aos pacientes portadores dos haplótipos LY, LX e HX. Os resultados do presente estudo mostram que a presença de haplótipos relacionados a médios e baixos níveis séricos de MBL podem ter um papel direto na forma como o paciente soropositivo evolui laboratorialmente. Desse modo, conclui-se que a caracterização dos haplótipos da região promotora do gene MBL em portadores da infecção pelo HIV-1 pode ser importante na avaliação do prognóstico de evolução da SIDA/AIDS.

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Pós-graduação em Agronomia (Produção Vegetal) - FCAV