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Purpose of the study is to evaluate performance of active portfolio management and the effect of stock market trend on the performance. Theory of efficient markets states that market prices reflect all available information and that all investors share a common view of future price developments. This view gives little room for the success of active management, but the theory has been disputed – at least the level of efficiency. Behavioral finance has developed theories that identify irrational behavior patterns of investors. For example, investment decisions are not made independent of past market developments. These findings give reason to believe that also the performance of active portfolio management may depend on market developments. Performance of 16 Finnish equity funds is evaluated during the period of 2005 to 2011. In addition two sub periods are constructed, a bull market period and a bear market period. The sub periods are created by joining together the two bull market phases and the two bear market phases of the whole period. This allows for the comparison of the two different market states. Performance of the funds is measured with risk-adjusted performance by Modigliani and Modigliani (1997), abnormal return over the CAPM by Jensen (1968), and market timing by Henriksson and Merton (1981). The results suggested that in average the funds are not able to outperform the market portfolio. However, the underperformance was found to be lower than the management fees in average which suggests that portfolio managers are able to do successful investment decisions to some extent. The study revealed substantial dependence on the market trend for all of the measures. The risk-adjusted performance measure suggested that in bear markets active portfolio managers in average are able to beat the market portfolio but not in bull markets. Jensen´s alpha and the market timing model also showed striking differences between the two market states. The results of these two measures were, however, somewhat problematic and reliable conclusions about the performance could not be drawn.

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The American bullfrog (Rana catesbeiana), recently named Lithobates catesbeianus is currently farmed for commercial purposes throughout various regions of Brazil. Stressful situations such as problems of management, inadequate facilities and environmental changes with consequent reduction of immunity are common in intensive production. The assessments of these situations of stress allow us detect these problems decreasing the injuries causes by confinement. The main objective of this study was to use the biological markers of plasma cortisol and glucose level and hematological parameters to evaluate the response of bullfrog tadpoles submitted to stressed mechanisms of capture and hypoxia. The animals were subjected to three treatments: stress due to individual capture with a hand net; stress due to batch capture with a hand net; and stress due to capture by emptying. The results obtained demonstrated that there were no statistically significant differences in the parameters tested when comparing the treatments with and without exposure to air (normoxia and hypoxia). Based on these results we can conclude that the stressful stimuli tested were not adequate to alter the biomarker tested. For the cortisol, probably this should have occurred due to the synergistic action between this hormone and thyroxin, which induces metamorphosis in these animals.

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The standard method for detection of bovine tuberculosis (TB) is the single intradermal tuberculin test (SITT). Nevertheless, current studies suggest that a single test is not enough to detect all cattle infected by TB, particularly when animals present different stages of infection. A dairy herd comprised of 270 cows was studied and 15 were reactive to SITT plus nine inconclusive animals. Blood samples (for IFN and ELISA) were collected from these 24 cows. At 30 days after injection of PPD, all the cows that were reactive to any of the employed tests were slaughtered, and tissues were processed by Bacteriology, Histopathology (HP) and PCR. According to HP 33.4% of the animals were positive, 45.8% inconclusive and 20.8% were negative. The inconclusive samples came from IFN positive animals, signalizing recent infection. Regarding the animals that were negative to HP, all of them were identified by IFN while ELISA was negative. Immune responses are different in recent and advanced infections, what supports the identification between chronically or recently infected animals. This multidisciplinary approach is mandatory for the interpretation of the various tools that are frequently employed for the diagnosis of TB and mainly to identify all infected animals.

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Asthma and allergy are common diseases and their prevalence is increasing. One of the hypotheses that explains this trend is exposure to inhalable chemicals such as traffi c-related air pollution. Epidemiological research supports this theory, as a correlation between environmental chemicals and allergic respiratory diseases has been found. In addition to ambient airborne particles, one may be exposed to engineered nanosized materials that are actively produced due to their favorable physico-chemical properties compared to their bulk size counterparts. On the cellular level, improper activity of T helper (Th) cells has been connected to allergic reactions. Th cells can differentiate into functionally different effector subsets, which are identifi ed according to their characteristic cytokine profi les resulting in specifi c ability to communicate with other cells. Th2 cells activate humoral immunity and stimulate eradication of extracellular pathogens. However, persistent predominance of Th2 cells is involved in a development of number of allergic diseases. The cytokine environment at the time of antigen recognition is the major factor determining the polarization of a naïve Th cell. Th2 cell differentiation is initiated by IL4, which signals via transcription factor STAT6. Although the importance of this pathway has been evaluated in the mouse studies, the signaling components involved have been largely unknown. The aim of this thesis was to identify molecules, which are under the control of IL4 and STAT6 in Th cells. This was done by using system-level analysis of STAT6 target genes at genome, mRNA and protein level resulting in identifi cation of various genes previously not connected to Th2 cell phenotype acquisition. In the study, STAT6-mediated primary and secondary target genes were dissection from each other and a detailed transcriptional kinetics of Th2 cell polarization of naïve human CD4+ T cells was collected. Integration of these data revealed the hierarchy of molecular events that mediates the differentiation towards Th2 cell phenotype. In addition, the results highlighted the importance of exploiting proteomics tools to complement the studies on STAT6 target genes identifi ed through transcriptional profi ling. In the last subproject, the effects of the exposure with ZnO and TiO2 nanoparticles was analyzed in Jurkat T cell line and in primary human monocyte-derived macrophages and dendritic cells to evaluate their toxicity and potential to cause infl ammation. Identifi cation of ZnO-derived gene expression showed that the same nanoparticles may elicit markedly distinctive responses in different cell types, thus underscoring the need for unbiased profi ling of target genes and pathways affected. The results gave additional proof that the cellular response to nanosized ZnO is due to leached Zn2+ ions. The approach used in ZnO and TiO2 nanoparticle study demonstrated the value of assessing nanoparticle responses through a toxicogenomics approach. The increased knowledge of Th2 cell signaling will hopefully reveal new therapeutic nodes and eventually improve our possibilities to prevent and tackle allergic infl ammatory diseases.

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A herd infected naturally with tuberculosis was investigated by different diagnostic methods. Ninety days after a screening test that identified 21 cows as skin test positive, a Comparative Intradermal Tuberculin Test (CITT) was performed in those 21 cows and in 29 other randomly selected skin test negative cows. Milk samples and nasal swabs were collected prior to the CITT for bacteriological culture and PCR, while blood samples were collected for IFN release and antibody responses to MPB70 and MPB83, at three time points post tuberculin injection. Animals positive by CITT were slaughtered and disease confirmation undertaken. Based on the Kappa test, IFN was comparable to the standard tests (culture, PCR and CITT) at all three sampling points. Results from both antibody ELISAs were similar but were not comparable to the standard tests. T-test analysis of the CITT, IFN and ELISAs demonstrated that their performances were not correlated. There is increasing recognition that individually, available diagnostic tests do not detect all infected cattle. Therefore, a comprehensive strategy for the diagnosis of bovine TB should include test results for the detection of both cellular and humoral immune responses where there may be animals at different stages of infection.

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The behavioural finance literature expects systematic and significant deviations from efficiency to persist in securities markets due to behavioural and cognitive biases of investors. These behavioural models attempt to explain the coexistence of intermediate-term momentum and long-term reversals in stock returns based on the systematic violations of rational behaviour of investors. The study investigates the anchoring bias of investors and the profitability of the 52-week momentum strategy (GH henceforward). The relatively highly volatile OMX Helsinki stock exchange is a suitable market for examining the momentum effect, since international investors tend to realise their positions first from the furthest security markets by the time of market turbulence. Empirical data is collected from Thomson Reuters Datastream and the OMX Nordic website. The objective of the study is to provide a throughout research by formulating a self-financing GH momentum portfolio. First, the seasonality of the strategy is examined by taking the January effect into account and researching abnormal returns in long-term. The results indicate that the GH strategy is subject to significantly negative revenues in January, but the strategy is not prone to reversals in long-term. Then the predictive proxies of momentum returns are investigated in terms of acquisition prices and 52-week high statistics as anchors. The results show that the acquisition prices do not have explanatory power over the GH strategy’s abnormal returns. Finally, the efficacy of the GH strategy is examined after taking transaction costs into account, finding that the robust abnormal returns remain statistically significant despite the transaction costs. As a conclusion, the relative distance between a stock’s current price and its 52-week high statistic explains the profits of momentum investing to a high degree. The results indicate that intermediateterm momentum and long-term reversals are separate phenomena. This presents a challenge to current behavioural theories, which model these aspects of stock returns as subsequent components of how securities markets respond to relevant information.

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Tässä tutkimuksessa selvitetään ilman hitsauslisäainetta tapahtuvan laser–TIG–hybridihitsausprosessin soveltuvuus 6 mm ja 8 mm paksujen päittäisliitettyjen S355 K2 ja Laser 355 MC rakenneterästen hitsaukseen. Hitsien tarkastelussa huomio kiinnitetään hitsausnopeuteen, hitsien tunkeumaan, liittämistehokkuuteen, hitsien kovuuteen ja hitsausliitoksen ulkonäköön. Muita tutkittavia asioita ovat laser-TIG-hybridihitsattujen levyjen muodonmuutokset ja suuresta hitsausnopeudesta sekä pienestä t8/5 jäähtymisajasta johtuvat mahdolliset kylmähalkeamat. Laser-TIG-hybridihitsejä verrataan robotti-MAG- ja käsin MAG-hitseihin sekä kaarihitsausstandardin SFS-EN ISO 5817 hitsiluokkien mukaisiin raja-arvoihin. Laser-TIG-hybridihitsausprosessissa TIG-valokaari mahdollistaa tasaisen ja lähes roiskeettoman hitsin ja lasersäde aikaansaa syvän tunkeuman sekä tasalaatuisen juurihitsin. Laser-TIG-hybridihitsausprosessilla 6 mm paksut S355 K2 rakenneteräslevyt on mahdollista hitsata levyn yhdeltä puolelta kerralla valmiiksi. Paksummat 8 mm levyt voidaan hitsata levyn yhdeltä tai molemmilta puolilta suoritettavalla laser-TIG-hybridihitsauksella. Laser-TIG-hybridihitsausprosessilla hitsatut hitsit ovat hyvin siistejä ja lähes roiskeettomia. Verrattaessa laser-TIG-hybridihitsausprosessia muihin hitsausprosesseihin sen voidaan todeta olevan erittäin kilpailukykyinen 6 mm paksujen päittäisliitettyjen rakenneterästen hitsaamisessa, mutta se soveltuu myös 8 mm paksujen rakenneterästen hitsaamiseen. Tutkitut hitsit täyttävät kaarihitsausstandardin SFS-EN ISO 5817 B- ja D-hitsiluokkien mukaiset raja-arvot. Vertailukokeet 6 mm paksulla S355 rakenneteräksellä osoittavat, että yhdeltä puolelta suoritettavan laser-TIG-hybridihitsauksen hitsausnopeus on robotti-MAG-hitsaukseen verrattuna yli nelinkertainen ja MAG-käsinhitsaukseen verrattuna yli viisinkertainen. Laser-TIG-hybridihitsauksessa liittämistehokkuus on noin viisinkertainen robotti-MAGhitsaukseen verrattuna. Molemmilta puolilta suoritettavalla laser-TIG-hybridihitsauksella voidaan 8 mm paksulla S355 rakenneteräksellä saavuttaa noin kolminkertainen hitsausnopeus ja liittämistehokkuus robotti-MAG-hitsaukseen verrattuna. Laser-TIG-hybridihitsauksessa TIG-kaaren tuoman lisälämmön ansiosta suurillakin hitsausnopeuksilla (1 m/min) voidaan saavuttaa edulliset kovuusarvot. Kovuusmittausten tulosten perusteella 6 mm ja 8 mm paksujen S355 K2 ja Laser 355 MC rakenneterästen hitsit eivät ylittäneet kaarihitsausstandardin määrittelemää 350 HV kovuuden enimmäisrajaa. Laser-TIG-hybridihitsauksen edullisesta lämmöntuonnista johtuen levyjen pituus- ja poikittaissuuntaiset muodonmuutokset ovat noin 80 prosenttia pienemmät kuin käsin suoritettavassa MAG-hitsauksessa. Laser-TIG-hybridihitsausprosessilla käytetään I-railoa, mutta robotti-MAG- ja käsin MAG-hitsausprosesseilla joudutaan käyttämään V-railoa, jolloin lämmöntuonti ja siitä johtuvat muodonmuutokset ovat suuremmat. Korkea liittämistehokkuus ja edullinen lämmöntuonti merkitsevät vähäisempiä muodonmuutoksia ja siten merkittäviä säästöjä työ-, materiaali- ja energiakustannuksissa. 8 mm ja sitä paksummilla S355 rakenneteräksillä levyn yhdeltä puolelta suoritettava päittäisliitoksen hitsaaminen on laser-TIG hybridihitsauksella haastavaa, koska yli 200 A:n TIG-kaarivirralla suuri metallisula aiheuttaa avaimenreiän sulkeutumisen ja avaimenreiän alaosaan muodostuu kaasukuplia. Tästä voidaan tehdä sellainen johtopäätös, että päittäisliitettävien levyjen ilmarakoa pitäisi kasvattaa niin suureksi, että avaimenreiän sulavirtaus ei pääse estymään. Yli 0,25 mm:n ilmarako edellyttää lasersäteen vaaputusta tai säteen halkaisijan kasvattamista. Ilmaraon kasvattaminen edellyttää myös lisäaineen käyttöä. Tutkimustulosten perusteella laser-TIG-hybridihitsausprosessilla voidaan saavuttaa merkittäviä etuja ja kustannussäästöjä, joten sen hyödyntämistä kannattaa harkita 8 mm ja sitä ohuempien päittäisliitettävien tuotteiden konepaja- ja tehdastuotannossa. Laser-TIGhybridihitsausprosessi soveltuu esimerkiksi seuraavien tuotteiden hitsaamiseen: päittäisliitettävät levyt, palkit, koneenosat, putket, säiliöt ja erilaiset pyörähdyskappaleet.

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Poverty alleviation views have shifted from seeing the poor as victims or as potential consumers, to seeing them as gainers. Social businesses include microfinancing and microfranchising, which engage people at the bottom of the pyramid using business instead of charity. There are, however, social business firms that do not fit to the existing social business model theory. These firms provide markets to poor producers and mix traditional, local craftsmanship with western design. Social business models evolve faster than the academic literature can study them. This study contributes to filling this gap. The purpose of this Master’s thesis is to develop the concept of social business as poverty alleviation method in developing countries. It also aims; 1) to describe the means for poverty alleviation in developing countries; 2) to introduce microbusiness as a social business model; and 3) to examine the challenges of microbusinesses. Qualitative case study is used as a research strategy and theme interviews as a data collecting method. The empirical data is gathered from four interviews of Finnish or Finnish-owned firms that employ microbusiness – Mifuko, Tensira, Mangomaa and Tikau – and this is supported with secondary data including articles on case companies. The results show that microbusiness is a valid new social business model that aims at poverty alleviation by engaging the poor at the bottom of the pyramid. It is possible to map the value proposition, value constellation, and economic and social profit equations of the case firms. Two major types of firms emerge from the results; the first consists of design-oriented firms that emphasize the quality and design of the products, and the second consists of bazaar-like firms whose product portfolio is less sophisticated and who promote more the stories of the products – not the design. All microbusiness firms provide markets, promote traditional handicrafts, form close relationships to their producers, and aim at enhancing lives through their businesses. The attitudes towards social businesses are sometimes negative, but this is changing for the better. In conclusion, microbusiness answers to two different needs at the same time – consumers’ needs for ethical products and the social needs of the producers – but the social need is the ultimate reason why the entrepreneurs started business. Microbusiness continues as a poverty alleviation tool that sees the poor as gainers; by providing them steady employment, microbusiness increases the poor’s self-esteem and enables them for a better living. Academic literature has not been able to offer enough alternative business models to cover all social businesses; the current study contributes to this by concluding that microbusiness is another social business model.

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This doctoral dissertation investigates the adult education policy of the European Union (EU) in the framework of the Lisbon agenda 2000–2010, with a particular focus on the changes of policy orientation that occurred during this reference decade. The year 2006 can be considered, in fact, a turning point for the EU policy-making in the adult learning sector: a radical shift from a wide--ranging and comprehensive conception of educating adults towards a vocationally oriented understanding of this field and policy area has been observed, in particular in the second half of the so--called ‘Lisbon decade’. In this light, one of the principal objectives of the mainstream policy set by the Lisbon Strategy, that of fostering all forms of participation of adults in lifelong learning paths, appears to have muted its political background and vision in a very short period of time, reflecting an underlying polarisation and progressive transformation of European policy orientations. Hence, by means of content analysis and process tracing, it is shown that the new target of the EU adult education policy, in this framework, has shifted from citizens to workers, and the competence development model, borrowed from the corporate sector, has been established as the reference for the new policy road maps. This study draws on the theory of governance architectures and applies a post-ontological perspective to discuss whether the above trends are intrinsically due to the nature of the Lisbon Strategy, which encompasses education policies, and to what extent supranational actors and phenomena such as globalisation influence the European governance and decision--making. Moreover, it is shown that the way in which the EU is shaping the upgrading of skills and competences of adult learners is modeled around the needs of the ‘knowledge economy’, thus according a great deal of importance to the ‘new skills for new jobs’ and perhaps not enough to life skills in its broader sense which include, for example, social and civic competences: these are actually often promoted but rarely implemented in depth in the EU policy documents. In this framework, it is conveyed how different EU policy areas are intertwined and interrelated with global phenomena, and it is emphasised how far the building of the EU education systems should play a crucial role in the formation of critical thinking, civic competences and skills for a sustainable democratic citizenship, from which a truly cohesive and inclusive society fundamentally depend, and a model of environmental and cosmopolitan adult education is proposed in order to address the challenges of the new millennium. In conclusion, an appraisal of the EU’s public policy, along with some personal thoughts on how progress might be pursued and actualised, is outlined.

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By so far, scholars have discussed how the characteristics of consumer co-operatives (cooperative principles, values and the dual role of members as the users and owners) can potentially give them a competitive advantage over investor-owned firms (IOFs). In addition, concern for the community (as partly derived from locality and regionality) has been seen as a potential source of success for consumer co-operatives. On the other hand, the geographicbound purpose of consumer co-operation causes that consumer co-operative can be regarded as a challenging company form to manage. This is because, according to the purpose of consumer co-operation, co-operatives are obligated to 1) provide the owners with services and goods that are needed and do so at more affordable prices than their competitors do and/or 2) to operate in areas in which competitors do not want to operate (for example, because of the low profitability in certain area of business or region). Thus, consumer co-operatives have to operate very efficiently in order to execute this geographic-bound corporate purpose (e.g. they cannot withdraw from the competition during the declining stages of business). However, this efficiency cannot be achieved by any means; as the acceptance from the important regional stakeholders is the basic operational precondition and lifeline in the long run. Thereby, the central question for the survival and success of consumer co-operatives is; how should the consumer co-operatives execute its corporate purpose so it can be the best alternative to its members in the long run? This question has remained unanswered and lack empirical evidence in the previous studies on the strategic management of consumer cooperation. In more detail, scholars have not yet empirically investigated the question: How can consumer co-operatives use financial and social capital to achieve a sustained competitive advantage? It is this research gap that this doctoral dissertation aims to fulfil. This doctoral dissertation aims to answer the above questions by combining and utilizing interview data from S Group co-operatives and the central organizations in S Group´s network (overall, 33 interviews were gathered), archival material and 56 published media articles/reports. The study is based on a qualitative case study approach that is aimed at theory development, not theory verification (as the theory is considered as nascent in this field of study). Firstly, the findings of this study indicate that consumer co-operatives accumulate financial capital; 1) by making profit (to invest and grow) and 2) by utilizing a network-based organizational structure (local supply chain economies). As a result of financial capital accumulation, consumer co-operatives are able to achieve efficiency gains but also remain local. In addition, a strong financial capital base increases consumer co-operatives´ independence, competitiveness and their ability to participate in regional development (which is in accordance with their geographically bound corporate purpose). Secondly, consumer cooperatives accumulate social capital through informal networking (with important regional stakeholders), corporate social responsibility (CSR) behaviour and CSR reporting, pursuing common good, and interacting and identity sharing. As a result of social capital accumulation, consumer co-operatives are able to obtain the resources for managing; 1) institutional dependencies and 2) customer relations. By accumulating both social and financial capital through the above presented actions, consumer co-operatives are able to achieve sustained competitive advantage. Finally, this thesis provides useful ideas and new knowledge for cooperative managers concerning why and how consumer co-operatives should accumulate financial and social capital (to achieve sustained competitive advantage), while aligning with their corporate purpose.

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The goals of the study were to describe patients’ perceptions of care after experiencing seclusion/restraint and their quality of life. The goal was moreover to identify methodological challenges related to studies from the perspective of coerced patients. The study was conducted in three phases between September 2008 and April 2012. In the first phase, the instrument Secluded/ Restrained Patients’ Perception of their Treatment (SR-PPT) was developed and validated in Japan in cooperation with a Finnish research group (n = 56). Additional data were collected over one year from secluded/restrained patients using the instrument (n = 90). In the second phase, data were collected during the discharge process (n = 264). In the third phase, data were collected from electronic databases. Methodological and ethical issues were reviewed (n = 32) using systematic review method. Patients perceived that co-operation with the staff was poor; patients’ opinions were not taken into account, treatment targets collated and treatment methods were seen in different ways. Patients also felt that their concerns were not well enough understood. However, patients received getting nurses’ time. In particular, seclusion/restraint was considered unnecessary. The patients felt that they benefited from the isolation in treating their problems more than they needed it, even if the benefit was seen to be minor. Patients treated on forensic wards rated their treatment and care significantly lower than in general units. During hospitalization secluded/restrained patients evaluated their quality of life, however, better than did non-secluded/restrained patients. However, no conclusion is drawn to the effect that the better quality of life assessment is attributable to the seclusion/restraint because patients’ treatment period after the isolation was long and because of many other factors, as rehabilitation, medication, diagnostic differences, and adaptation. According to the systematic mixed studies review variation between study designs was found to be a methodological challenge. This makes comparison of the results more difficult. A research ethical weakness is conceded as regards descriptions of the ethical review process (44 %) and informed consent (32 %). It can be concluded that patients in psychiatric hospital care and having a voice as an equal expert require special attention to clinical nursing, decision-making and service planning. Patients and their family members will be consulted in plans of preventive and alternative methods for seclusion and restraint. The study supports the theory that in ethical decision-making situations account should be taken of medical indications, in addition to the patients’ preferences, the effect of treatment on quality of life, and this depends on other factors. The connection between treatment decisions and a patient’s quality of life should be evaluated more structurally in practice. Changing treatment culture towards patients’ involvement will support daily life in nursing and service planning taking into account improvements in patients’ quality of life.

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The purpose of the study is to analyse lateral rigidity in the framework of pre-internationalisation to find out its reflections on managerial decision making. The interest of the study lies in the intersection of the meaningful but relatively stagnant concept of lateral rigidity, and the pre-internationalisation phase of companies that has received only a limited amount of research attention. The theoretical basis for the study is drawn from managerial decision making and internationalisation literatures. Firstly, the study aims to define the concept of lateral rigidity in order to secondly find out how it influences managers’ pre-internationalisation decision making. The study is theoretical in nature, and is based solely on literature examination. Concept analysis method is used to determine the attributes of lateral rigidity for the purpose of recognising the concept in the pre-internationalisation framework. The attributes that are found to comprise lateral rigidity are culture, know-how, uncertainty and attitude. Furthermore, these attributes are more specifically found to consist of environmental, personal and operational matters. Through the analysis of the pre-internationalisation literature it is discovered that all the attributes appear there, and present a variety of influences on pre-internationalisation decision making that can be characterised as being negative. The study finds that culture influences managers’ decision making via subjective reasoning and behaviour that stem from a domestic inclination, and via unfamiliarity with foreign markets. Against assumption, home cultural factors, e.g. values and customs, do not appear to have an influence. Know-how is found to influence decision making via managers’ previous experiences, subjective abiding perceptions, and the usage of previous operation patterns. Uncertainty, then again, influences managers’ risk perception, unfamiliarity avoidance, and the scope of potential international operations. Attitude is found to have a robust influence on managerial decision making via the usage of familiar processes and decision regimes, subjective preference of convention, and plausible results of operations. Ergo, the effects of lateral rigidity on managers show to represent an encumbrance in the pre-internationalisation phase; even though internationalisation would take place, the related decisions and actions are highly constrained. Especially the subjectivity of managers is seen to have a meaningful role in the decision making process.

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Studies related to weed dynamics are essential for agricultural sustainability in tropical soils, as their interference can cause significant yield losses, especially in crops with lower competitive ability. This study aimed to assess the composition of weed communities in the third cropping season in areas submitted to distinct wintercroppings for two consecutive years. Evaluations were made in terms of species composition, level of infestation, and severity of occurrence of each weed species in relation to the others within the same area. The wintercropping management systems were: (1) Brachiaria ruziziensis; (2) corn intercropped with B. ruziziensis; (3) corn and (4) cowpea. Plant communities under these wintercrop systems were evaluated in the third year in terms of relative frequency, relative dominance, relative abundance and importance index for each species. Areas were also compared in terms of species composition by the Sorensen's similarity coefficient. Two years of distinct wintercrop managements were not enough to cause a significant shift in terms of weed composition and severity in a given area. There is also evidence that some weed species are more favored by specific crops, although the causes of this selective behavior are not fully explored in this article. The presence of B. ruziziensis, either alone or intercropped with corn, resulted in lower similarity coefficients when compared to areas where this species was not present. It is suggested that several mechanisms briefly discussed may be involved in the impact of the presence of B. ruziziensis on the weed community.

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The resistance of barnyardgrass (Echinochloa crus-galli) to imidazolinone herbicides is a worldwide problem in paddy fields. A rapid diagnosis is required for the selection of adequate prevention and control practices. The objectives of this study were to develop expedite bioassays to identify the resistance to imidazolinone herbicides in barnyardgrass and to evaluate the efficacy of alternative herbicides for the post-emergence control of resistant biotypes. Three experiments were conducted to develop methods for diagnosis of resistance to imazethapyr and imazapyr + imazapic in barnyardgrass at the seed, seedling and tiller stages, and to carry out a pot experiment to determine the efficacy of six herbicides applied at post-emergence in 13 biotypes of barnyardgrass resistant to imidazolinones. The seed soaking bioassay was not able to differentiate the resistant and susceptible biotypes. The resistance of barnyardgrass to imidazolinones was effectively discriminated in the seedlings and tiller bioassays seven days after incubation at the concentrations of 0.001 and 0.0001 mM, respectively, for both imazethapyr and imazapyr + imazapic. The biotypes identified as resistant to imidazolinones showed different patterns of susceptibility to penoxsulam, bispyribac-sodium and pyrazosulfuron-ethyl, and were all controlled with profoxydim and cyhalofop-butyl. The seedling and tiller bioassays are effective in the diagnosis of barnyardgrass resistance to imidazolinone herbicides, providing an on-season opportunity to identify the need to use alternative herbicides to be applied at post-emergence for the control of the resistant biotypes.

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ALS-inhibiting herbicides usually provide adequate weed control in irrigated rice fields. After consecutive years of use, the Cyperaceae species, globe fringerush (Fimbristylis miliacea) began to show resistance to ALS (acetolactate synthase) inhibitors. Globe fringerush is one of the most problematic herbicide-resistant weeds in irrigated rice in the state of Santa Catarina in the South of Brazil. The objective of this research was to examine cross resistance of globe fringerush to ALS inhibitors, under field conditions. Two experiments were conducted in a rice field naturally infested with ALS-resistant globe fringerush in Santa Catarina, in the 2008/09 and 2009/10 cropping seasons. The experimental units were arranged in randomized complete block design, with five replicates, consisting of two factors (herbicide and dose) in a 4 x 5 factorial arrangement. ALS herbicides included bispyribac-sodium, ethoxysulfuron, pyrazosulfuron-ethyl and penoxsulam. Six-leaf globe fringerush was sprayed with herbicide doses of 0, 0.5, 1, 2 and 4X the recommended doses in a spray volume of 200 L ha-1. The number of rice culm, filled and sterile grains, plant height, dry shoot biomass and grain yield were recorded. Globe fringerush control was evaluated 28 and 70 days after herbicide application (DAA); shoots were harvested at 13 weeks after herbicide application and dry weight recorded. Competition with globe fringerush reduced the number of culm and rice grain yield. The globe fringerush biotype in this field was resistant to all ALS herbicides tested. Penoxsulam had the highest level of activity among treatments at 28 and 70 DAA, but the control level was only 50% and 42%, respectively, in the second year of assessment. This was not enough to prevent rice yield loss. Alternative herbicides and weed control strategies are necessary to avoid yield losses in rice fields infested with ALS-resistant biotypes of globe fringerush.