946 resultados para Oxidoreductases Acting on Sulfur Group Donors
Resumo:
Metacaspases (MCAs) are cysteine peptidases expressed in plants, fungi and protozoa, with a caspase-like histidine-cysteine catalytic dyad, but differing from caspases, for example, in their substrate specificity. The role of MCAs is subject to debate: roles in cell cycle control, in cell death or even in cell survival have been suggested. In this study, using a Leishmania major MCA-deficient strain, we showed that L. major MCA (LmjMCA) not only had a role similar to caspases in cell death but also in autophagy and this through different domains. Upon cell death induction by miltefosine or H2O2, LmjMCA is processed, releasing the catalytic domain, which activated substrates via its catalytic dyad His/Cys and a proline-rich C-terminal domain. The C-terminal domain interacted with proteins, notably proteins involved in stress regulation, such as the MAP kinase LmaMPK7 or programmed cell death like the calpain-like cysteine peptidase. We also showed a new role of LmjMCA in autophagy, acting on or upstream of ATG8, involving Lmjmca gene overexpression and interaction of the C-terminal domain of LmjMCA with itself and other proteins. These results allowed us to propose two models, showing the role of LmjMCA in the cell death and also in the autophagy pathway, implicating different protein domains.
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Clines in chromosomal inversion polymorphisms-presumably driven by climatic gradients-are common but there is surprisingly little evidence for selection acting on them. Here we address this long-standing issue in Drosophila melanogaster by using diagnostic single nucleotide polymorphism (SNP) markers to estimate inversion frequencies from 28 whole-genome Pool-seq samples collected from 10 populations along the North American east coast. Inversions In(3L)P, In(3R)Mo, and In(3R)Payne showed clear latitudinal clines, and for In(2L)t, In(2R)NS, and In(3R)Payne the steepness of the clinal slopes changed between summer and fall. Consistent with an effect of seasonality on inversion frequencies, we detected small but stable seasonal fluctuations of In(2R)NS and In(3R)Payne in a temperate Pennsylvanian population over 4 years. In support of spatially varying selection, we observed that the cline in In(3R)Payne has remained stable for >40 years and that the frequencies of In(2L)t and In(3R)Payne are strongly correlated with climatic factors that vary latitudinally, independent of population structure. To test whether these patterns are adaptive, we compared the amount of genetic differentiation of inversions versus neutral SNPs and found that the clines in In(2L)t and In(3R)Payne are maintained nonneutrally and independent of admixture. We also identified numerous clinal inversion-associated SNPs, many of which exhibit parallel differentiation along the Australian cline and reside in genes known to affect fitness-related traits. Together, our results provide strong evidence that inversion clines are maintained by spatially-and perhaps also temporally-varying selection. We interpret our data in light of current hypotheses about how inversions are established and maintained.
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Diplomityön pääasiallisena tarkoituksena oli selvittää Peikko Finland Oy:n asiakastyytyväisyyden nykytila sekä kehittää pitkäkestoinen malli asiakastyytyväisyyden säännölliselle mittaamiselle. Työn tarkoituksena ei ole tarjota valmiita ratkaisuja, vaan antaa yrityksen toiminnan ja kilpailukyvyn kehittämistä varten tarvittavaa tietoa asiakaslähtöisestä näkökulmasta. Asiakastyytyväisyystutkimus suoritettiin sähköisenä kyselynä suunnittelutoimistoille ja eri toimialojen asiakkaille. Lisäksi suoritettiin sisäinen kysely yrityksen johtoryhmän keskuudessa. Saatujen vastausten pohjalta saatiin luotua sekä yrityksen sisäinen että ulkopuolinen näkemys asiakastyytyväisyyden tilasta. Yleisesti ottaen asiakastyytyväisyyden tila oli kohtuullisen hyvällä tasolla. Asiakkaiden ja suunnittelutoimistojen kokema tyytyväisyystaso oli keskimäärin yrityksen sisällä oletettua tasoa parempi. Hyvin kriittisiä kehitystarpeita ilmeni suhteellisen vähän. Suurimmat kehitystarpeet liittyivät tuotteiden hinnoitteluun. Diplomityön osalta asiakastyytyväisyystutkimus suoritettiin Suomen asiakaskunnassa. Tulevaisuudessa kehitetyn kyselypohjan pohjalta asiakastyytyväisyysselvitykset on tarkoitus suorittaa koko konsernitasolla.
Propriedades fotofísicas de Eu3+ e Tb3+ imobilizados em sílica gel funcionalizada com beta-Dicetonas
Resumo:
Synthetic procedures, characterization and luminescent properties of Eu3+ and Tb3+ ions supported on silica gel functionalized with beta-diketones are presented. The functionalization with propyl benzoyltrifluoroacetone (BPG), dibenzoylmethane (DBM) and hexafluoroacetone (HPG), leads to new luminescent materials which photophysical properties depend on the group substituent in the beta-diketone. These systems were evaluated in terms of luminescence and lifetime of the Eu3+ and Tb3+ ions. Silica functionalization was confirmed by TGA and Elemental Analysis. The sample contents of ions were from 0,2 to 0,3 % (w/w).
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The replicative cycle of HIV presents several events. The proteins involved in these events can be anticipated as pharmacological targets, aiming to the development of anti viral agents. Presently, there are fifteen commercially available anti-HIV drugs, which act at substrate binding site of reverse transcriptase (zidovudine, didanosine, zalcitabine, stavudine, lamivudine and abacavir), at a non-substrate binding site of reverse transcriptase (nevirapine, delavirdine and efavirenz), or by inhibiting HIV protease activity (saquinavir, ritonavir, indinavir, nelfinavir, amprenavir and lopinavir). The present review focus both on these established classes of drugs and on new classes of compounds acting on other virus specific steps.
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Salvage logging is a common practice carried out in burned forests worldwide, and intended to mitigate the economic losses caused by wildfires. Logging implies an additional disturbance occurring shortly after fire, although its ecological effects can be somewhat mitigated by leaving wood debris on site. The composition of the bird community and its capacity to provide ecosystem services such as seed dispersal offleshy-fruited plants have been shown to be affected by postfire logging. We assessedthe effects of the habitat structure resulting from different postfire management practices on the bird community, in three burned pine forests in Catalonia (western Mediterranean). For this purpose, we focused on the group of species that is responsible for seed dispersal, a process which takes place primarily during the winter in theMediterranean basin. In addition, we assessed microhabitat selection by seed disperser birds in such environments in relation to management practices. Our results showed a significant, positive relationship between the density of wood debris piles and the abundance of seed disperser birds. Furthermore, such piles were the preferredmicrohabitat of these species. This reveals an important effect of forest management on seed disperser birds, which is likely to affect the dynamics of bird-dependent seed dispersal. Thus, building wood debris piles can be a useful practice for the conservation of both the species and their ecosystem services, while also being compatible with timber harvesting
Resumo:
Skenaarioita käytetään usein ylimmän johdon strategiasuunnitteluvälineinä. Tämän tutkimuksen tavoitteena oli selvittää vaikuttavatko skenaariot ja skenaariotyöskentely organisaation oppimiseen laajemminkin kuin yksilötasolla ja minkälaista oppimista tapahtuu sekä minkälaisia ominaisuuksia skenaariotyötä johtavalla olisi hyvä olla. Tutkimusaineisto on kerätty haastattelemalla skenaariotöitä johtanutta henkilöä sekä niihin osallistuneita henkilöitä. Tutkittavana oli kaksi skenaariotyötä, joista toisen tavoittena oli kuvata tulevaisuuden mobiileja liiketoimintamalleja ja toisen mallintaa verkko-operaattoriliiketoiminnan tulevaisuutta. Tutkimuksen aikana selvisi, että skenaarioilla ja skenaariotyöskentelyllä voi tukea organisaation oppimista niin yksilön, ryhmän/organisaation kuin organisaatioiden väliselläkin tasolla. Skenaariotyötä tekevällä ryhmällä ja sitä johtavalla henkilöllä on vaikutusta organisaation oppimiseen. Erityisen tärkeää organisaation oppimisen kannalta on, kuinka skenaariotyöskentely aloitetaan ja lopetetaan.
Resumo:
The focus of this study is to examine the role of police and immigrants’ relations, as less is known about this process in the country. The studies were approached in two different ways. Firstly, an attempt was made to examine how immigrants view their encounters with the police. Secondly, the studies explored how aware the police are of immigrants’ experiences in their various encounters and interactions on the street level. An ancillary aim of the studies is to clarify, analyse and discuss how prejudice and stereotypes can be tackled, thereby contributing to the general debate about racism and discrimination for better ethnic relations in the country. The data in which this analysis was based is on a group of adults (n=88) from the total of 120 Africans questioned for the entire study (n=45) police cadets and (n=6) serving police officers from Turku. The present thesis is a compilation of five articles. A summary of each article findings follows, as the same data was used in all five studies. In the first study, a theoretical model was developed to examine the perceived knowledge of bias by immigrants resulting from race, culture and belief. This was also an attempt to explore whether this knowledge was predetermined in my attempt to classify and discuss as well as analyse the factors that may be influencing immigrants’ allegations of unfair treatment by the police in Turku. The main finding shows that in the first paper there was ignorance and naivety on the part of the police in their attitudes towards the African immigrant’s prior experiences with the police, and this may probably have resulted from stereotypes or their lack of experience as well as prior training with immigrants where these kinds of experience are rampant in the country (Egharevba, 2003 and 2004a). In exploring what leads to stereotypes, a working definition is the assumption that is prevalent among some segments of the population, including the police, that Finland is a homogenous country by employing certain conducts and behaviour towards ethnic and immigrant groups in the country. This to my understanding is stereotype. Historically this was true, but today the social topography of the country is changing and becoming even more complex. It is true that, on linguistic grounds, the country is multilingual, as there are a few recognised national minority languages (Swedish, Sami and Russian) as well as a number of immigrant languages including English. Apparently it is vital for the police to have a line of communication open when addressing the problem associated with immigrants in the country. The second paper moved a step further by examining African immigrants’ understanding of human rights as well as what human rights violation means or entails in their views as a result of their experiences with the police, both in Finland and in their country of origin. This approach became essential during the course of the study, especially when the participants were completing the questionnaire (N=88), where volunteers were solicited for a later date for an in-depth interview with the author. Many of the respondents came from countries where human rights are not well protected and seldom discussed publicly, therefore understanding their views on the subject can help to explain why some of the immigrants are sceptical about coming forward to report cases of batteries and assaults to the police, or even their experiences of being monitored in shopping malls in their new home and the reason behind their low level of trust in public authorities in Finland. The study showed that knowledge of human rights is notably low among some of the participants. The study also found that female respondents were less aware of human rights when compared with their male counterparts. This has resulted in some of the male participants focussing more on their traditional ways of thinking by not realising that they are in a new country where there is equality in sexes and lack of respect on gender terms is not condoned. The third paper focussed on the respondents’ experiences with the police in Turku and tried to explore police attitudes towards African immigrant clients, in addition to the role stereotype plays in police views of different cultures and how these views have impacted on immigrants’ views of discriminatory policing in Turku. The data is the same throughout the entire studies (n=88), except that some few participants were interviewed for the third paper thirty-five persons. The results showed that there is some bias in mass-media reports on the immigrants’ issues, due to selective portrayal of biases without much investigation being carried out before jumping to conclusions, especially when the issues at stake involve an immigrant (Egharevba, 2005a; Egharevba, 2004a and 2004b). In this vein, there was an allegation that the police are even biased while investigating cases of theft, especially if the stolen property is owned by an immigrant (Egharevba, 2006a, Egharevba, 2006b). One vital observation from the respondents’ various comments was that race has meaning in their encounters and interaction with the police in the country. This result led the author to conclude that the relation between the police and immigrants is still a challenge, as there is rampant fear and distrust towards the police by some segments of the participating respondents in the study. In the fourth paper the focus was on examining the respondents’ view of the police, with special emphasis on race and culture as well as the respondents’ perspective on police behaviour in Turku. This is because race, as it was relayed to me in the study, is a significant predictor of police perception (Egharevba, 2005a; Egharevba and Hannikianen, 2005). It is a known scientific fact that inter-group racial attitudes are the representation of group competition and perceived threat to power and status (Group-position theory). According to Blumer (1958) a sense of group threat is an essential element for the emergence of racial prejudice. Consequently, it was essential that we explored the existing relationship between the respondents and the police in order to have an understanding of this concept. The result indicates some local and international contextual issues and assumptions that were of importance tackling prejudice and discrimination as it exists within the police in the country. Moreover, we have to also remember that, for years, many of these African immigrants have been on the receiving end of unjust law enforcement in their various countries of origin, which has resulted in many of them feeling inferior and distrustful of the police even in their own country of origin. While discussing the issues of cultural difference and how it affects policing, we must also keep in mind the socio-cultural background of the participants, their level of language proficiency and educational background. The research data analysed in this study also confirmed the difficulties associated with cultural misunderstandings in interpreting issues and how these misunderstandings have affected police and immigrant relations in Finland. Finally, the fifth paper focussed on cadets’ attitudes towards African immigrants as well as serving police officers’ interaction with African clients. Secondly, the police level of awareness of African immigrants’ distrustfulness of their profession was unclear. For this reason, my questions in this fifth study examined the experiences and attitudes of police cadets and serving police officers as well as those of African immigrants in understanding how to improve this relationship in the country. The data was based on (n=88) immigrant participants, (n=45) police cadets and 6 serving police officers from the Turku police department. The result suggests that there is distrust of the police in the respondents’ interaction; this tends to have galvanised a heightened tension resulting from the lack of language proficiency (Egharevba and White, 2007; Egharevba and Hannikainen, 2005, and Egharevba, 2006b) The result also shows that the allegation of immigrants as being belittled by the police stems from the misconceptions of both parties as well as the notion of stop and search by the police in Turku. All these factors were observed to have contributed to the alleged police evasiveness and the lack of regular contact between the respondents and the police in their dealings. In other words, the police have only had job-related contact with many of the participants in the present study. The results also demonstrated the complexities caused by the low level of education among some of the African immigrants in their understanding about the Finnish culture, norms and values in the country. Thus, the framework constructed in these studies embodies diversity in national culture as well as the need for a further research study with a greater number of respondents (both from the police and immigrant/majority groups), in order to explore the different role cultures play in immigrant and majority citizens’ understanding of police work.
Resumo:
The furrow openers for no-till system should be easy to penetrate the soil, generate low levels of soil mobilization and require a little traction force. Thus, the aim of this research was to compare six hoe-type furrow openers, four of industrial manufacturing and two handcrafted models, which were used in planters in the region of Pelotas, Brazil. The parameters for comparison among these furrow openers were the horizontal (Fh) and vertical (Fv) forces acting on the tip of the hoe and the cross-sectional area mobilized in the furrow. The experimental design was randomized, with six treatments (furrow openers) from T1 to T6, with four repetitions, constituted by their passage through plots of 20 x 3 m. The force data were collected by load cells and a signal conditioner. The determination of the mobilized area in the furrow was done by a micro soil profilometer. It was concluded that the furrow openers T1, T4 and T6 presented the lowest values of horizontal force (statistically equal and ranging between 1,034 and 1,230 N) and that T1 and T2 produced the highest vertical forces downwards (statistically identical and varying between 749 and 845 N). The furrow openers T1, T2, T4, T5 and T6 generated soil mobilization statistically equal and between 0.006993 and 0.008933 m².
Resumo:
The wear resistance of rotary plows operating in a clay loam soil was studied. The degree of damage caused to the soil and the amount of mass lost by the tools were determined in order to establish correlations between the physical properties of the soil and the wear mechanisms acting on the tribosystem. Field tests were carried out in 12 plots and a randomized experimental design with 4 levels, 3 replicas per level and 2 passes per plot was applied. The levels relate to the tillage implements employed: rotary tiller, rotary power harrow, small motorized rotary tiller and control (unaltered soil). The highest mass losses were measured in rotary tiller and rotary power harrow's tools, while the small motorized rotary tiller's tools showed generally lower levels of damage. It was determined that the effective contact time between tool and soil, the rotating speed and the sudden impact forces are the most significant factors affecting the wear resistance in field operations. Thirty days after tillage operation the soil samples were taken from each plot at a mean depth of 100 mm in order to determine bulk density, gravimetric moisture content and percentage of aggregates smaller than 5 mm. No significant differences among the values of these properties were found in the experiments. The wear mechanisms acting on the tools' surface are complex and include 2-body and 3-body abrasion as well as the presence of sudden impact forces.
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OBJECTIVE: To evaluate the effects of topical policresulen and cinchocaine in the postoperative pain behavior of open hemorrhoidectomy.METHODS: We conducted a prospective, double-blinded, controlled study. The control group received the usual guidelines with oral medications. The topical treatment group received, in addition, the application of the ointment and was comprised of two subgroups (policresulen + cinchocaine, and placebo). Pain intensity was recorded with the visual analogue scale.RESULTS: 43 patients were operated on: control group - n = 13, one excluded; placebo - n = 15; and policresulen + cinchocaine - n = 15. The mean age was 45.98 years and 37.2% were men. The average pain intensity was 4.09 (immediate postoperative), 3.22 (hospital discharge), 5.73 (day 1) , 5.77 (day 2), 5.74 (day 3), 5.65 (day 7), 5.11 (day 10), 2.75 (day 15) and 7.70 (first bowel movement), with no difference between groups in all periods.CONCLUSION: This study showed no reduction in pain after hemorrhoidectomy with the use of topical policresulen and cinchocaine.
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The purpose of the thesis is to classify suppliers and to enhance strategic purchasing in the case company. Supplier classification is conducted to fulfill the requirements of the company quality manual and international quality standards. To gain more benefit, a strategic purchasing tool, Kraljic’s purchasing portfolio and analytical hierarchy process are utilized for the base of supplier classification. Purchasing portfolio is used to give quick and easy visual insight on product group management form the viewpoint of purchasing. From the base on purchasing portfolio alternative purchasing and supplier strategies can be formed that enhance the strategic orientation of purchasing. Thus purchasing portfolio forces the company to orient on proactive and strategic purchasing. As a result a survey method for implementing purchasing portfolio in the company is developed that exploits analytical hierarchy process. Experts from the company appoint the categorization criteria and in addition, participate in the survey to categorize product groups on the portfolio. Alternative purchasing strategies are formed. Suppliers are classified depending on the importance and characteristics of the product groups supplied.
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Fireside deposits can be found in many types of utility and industrial furnaces. The deposits in furnaces are problematic because they can reduce heat transfer, block gas paths and cause corrosion. To tackle these problems, it is vital to estimate the influence of deposits on heat transfer, to minimize deposit formation and to optimize deposit removal. It is beneficial to have a good understanding of the mechanisms of fireside deposit formation. Numerical modeling is a powerful tool for investigating the heat transfer in furnaces, and it can provide valuable information for understanding the mechanisms of deposit formation. In addition, a sub-model of deposit formation is generally an essential part of a comprehensive furnace model. This work investigates two specific processes of fireside deposit formation in two industrial furnaces. The first process is the slagging wall found in furnaces with molten deposits running on the wall. A slagging wall model is developed to take into account the two-layer structure of the deposits. With the slagging wall model, the thickness and the surface temperature of the molten deposit layer can be calculated. The slagging wall model is used to predict the surface temperature and the heat transfer to a specific section of a super-heater tube panel with the boundary condition obtained from a Kraft recovery furnace model. The slagging wall model is also incorporated into the computational fluid dynamics (CFD)-based Kraft recovery furnace model and applied on the lower furnace walls. The implementation of the slagging wall model includes a grid simplification scheme. The wall surface temperature calculated with the slagging wall model is used as the heat transfer boundary condition. Simulation of a Kraft recovery furnace is performed, and it is compared with two other cases and measurements. In the two other cases, a uniform wall surface temperature and a wall surface temperature calculated with a char bed burning model are used as the heat transfer boundary conditions. In this particular furnace, the wall surface temperatures from the three cases are similar and are in the correct range of the measurements. Nevertheless, the wall surface temperature profiles with the slagging wall model and the char bed burning model are different because the deposits are represented differently in the two models. In addition, the slagging wall model is proven to be computationally efficient. The second process is deposit formation due to thermophoresis of fine particles to the heat transfer surface. This process is considered in the simulation of a heat recovery boiler of the flash smelting process. In order to determine if the small dust particles stay on the wall, a criterion based on the analysis of forces acting on the particle is applied. Time-dependent simulation of deposit formation in the heat recovery boiler is carried out and the influence of deposits on heat transfer is investigated. The locations prone to deposit formation are also identified in the heat recovery boiler. Modeling of the two processes in the two industrial furnaces enhances the overall understanding of the processes. The sub-models developed in this work can be applied in other similar deposit formation processes with carefully-defined boundary conditions.
Resumo:
Tiedon tehokas jakaminen ja tiedon hallinta näyttelee tärkeätä roolia yritysten kannattavuuden ja tehokkuuden kehittämisessä. Laadukkaan tiedon tehokas jakaminen ja omaksuminen korostuvat verkostoituneessa logistiikkaketjussa ja kolmannen osapuolen logistiikkaa harjoittavissa yrityksissä. Tehokkaalla tiedon jakamisella, tietämyksen hallinnalla sekä tietojohtamisen keinoilla voidaan luoda tehokkaita ja kilpailukykyisiä businessprosesseja. Työn tuloksena saavutettiin kuvaus tietojohtamisen eri näkökulmista sekä tietojohtamisesta tiedon hallinnan työkaluna. Työn teoreettisessa osuudessa käsitellään tietoa ja sen eri tasoja sekä perspektiivejä tietojohtamisessa käytettyinä syötteinä, sen prosesseina sekä lopputuloksena, joita tietojohtamisen käsitteen alla olevilla työkaluilla ja käytännöillä toteutetaan. Aiempi tutkimus osoittaa, että tietojohtaminen on yksi johtamisen malli, jonka avulla voidaan saavuttaa tehokkaan yritystoiminnan edellytykset sekä asetetut strategiset tavoit- teet. Kirjallisuuden perusteella pyrittiin kartoittamaan verkostoituneen logistiikkaketjun tiedonhallinnan esteet ja sitä rajoittavat tekijät. Työn empiirinen osuus toteutettiin kvalitatiivisena kysely- sekä haastattelututkimuksena, jonka avulla kerättiin työssä käytetty tutkimusaineisto. Työn empiirisessä osuudessa kartoitettiin kohdeorganisaation tiedonhallintaprosesseja sen kuljetustuotannon toiminnoissa, sekä niiden toteuttamista vaikeuttavia ja hidastavia tekijöitä. Empiirisen aineiston perusteella yritykselle ehdotettiin organisaation muokkaamista enemmän tiedon jakamista tu- kevaan suuntaan, joka voidaan teoriatiedon perusteella toteuttaa esimerkiksi luomalla fyysisiä ja henkisiä tiloja tietoprosessien toteuttamiselle.
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Teiden liukkauden mittaaminen on herättänyt kiinnostusta viime vuosina. Liikenneturvallisuutta pystyttäisiin parantamaan ja teiden talvikunnossapitoa tehostamaan, mikäli kitkakerroin voitaisiin mitata tiestöä käyttävissä ajoneuvoissa. Tässä työssä suunnitellaan ja toteutetaan ajoneuvon pituussuuntaiseen dynamiikkaan perustuva kitkakertoimen mittausjärjestelmä. Pyörien luisto ja ajoneuvon nopeus, sekä pyöriin ja ajoneuvoon kohdistuvat voimat selvitetään CAN – väylästä luettavien ajoneuvon antureiden ja IMU:n avulla. Järjestelmää simuloidaan käyttämällä Matlab:ia ja testataan käytännössä VW Transporter pakettiautossa. Testitulokset osoittavat järjestelmän toimivan tarkasti ja että ajoneuvon dynamiikkaan perustuvan kitkakertoimen mittauksen on käyttökelpoinen ja kustannustehokas tapa teiden liukkauden valvomiseen.