988 resultados para entrepreneurial self


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In earlier work, nonisomorphic graphs have been converted into networks to realize Multistage Interconnection networks, which are topologically nonequivalent to the Baseline network. The drawback of this technique is that these nonequivalent networks are not guaranteed to be self-routing, because each node in the graph model can be replaced by a (2 × 2) switch in any one of the four different configurations. Hence, the problem of routing in these networks remains unsolved. Moreover, nonisomorphic graphs were obtained by interconnecting bipartite loops in a heuristic manner; the heuristic nature of this procedure makes it difficult to guarantee full connectivity in large networks. We solve these problems through a direct approach, in which a matrix model for self-routing networks is developed. An example is given to show that this model encompases nonequivalent self-routing networks. This approach has the additional advantage in that the matrix model itself ensures full connectivity.

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International new ventures (INVs) are firms that engage very early after their foundation, if not immediately, in inter-national activities. INVs are a relatively recent phenomenon that deviates from earlier theories on international business. In order to develop our understanding of the emergence and early internationalisation of INVs three different research areas are built upon in the dissertation: International Entrepreneurship, Entrepreneurship and Networks. Net-works have been identified as important for INVs. However, there is a lack of more profound studies regarding the way different types of relationships influence INVs. Few studies are concerned with exploration and exploitation of opportunities and research on the benefits and drawbacks of entrepreneurs’ relationships for the international opportunity recognition process has been called for. By taking a network approach to opportunity exploration and exploitation, the dissertation develops our under-standing of how entrepreneurs’ relationships are involved in exploring and exploiting opportunities during an INV’s early and critical entrepreneurial and internationalisation events. The critical events are studied during three phases: pre-founding, start-up and early internationalisation. Since internationalisation is present from the very beginning, the early internationalisation phase may be parallel to both the pre-founding and the start-up phase. The dissertation contributes to international entrepreneur-ship research in mainly two ways. First, by offering a deep insight into which opportunity exploration and exploitation activities entrepreneurs’ relationships are involved. Second, by adding to our understanding of what the relationships contribute to these activities, mainly in the sense of benefits gained through the relationships. Studying micro firms in real time in their early development towards INVs is considered a unique contribution of the study as it offers valuable insights into pre-founding, start-up, pre-internationalisation as well as early internationalisation. The study shows that in order to understand the development of INVs, it is beneficial to go back to times when there was no thought of starting the INV. By focusing on the entrepreneurs’ background and relationships a more complete picture of the INV is gained. Relationships created at former workplaces or during school time might be the ones that develop business opportunities and set off internationalisation. By focusing on the pre-founding phase, the study also contributes to entrepreneurship literature as this stage has often been neglected or assumed obvious in earlier research. This dissertation shows that an important and mostly lengthy pre-founding phase precedes the decision to start a f rm. In addition, the integration of entrepreneurs’ real experiences with existing theory to develop a continuum for the strength of relationships allows for contributions to network theory.

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ABSTRACT Bakhshandeh, Soheila. Periodontal and dental health and oral self-care among adults with diabetes mellitus. Department of Oral Public Health, Institute of Dentistry, Faculty of Medicine, University of Helsinki, Helsinki, Finland. 2011. 49 pp. ISBN 978-952-10-7193-5(paperback). The aim of the present study was to assess oral health and treatment needs among Iranian adults with diabetes according to socio-demographic status, oral hygiene, diabetes related factors, and to investigate the relation between these determinants and oral health. Moreover, the effect of an educational oral health promotion intervention on their oral health and periodontal treatment needs was studied. The target population comprised adults with diabetes in Tehran, Iran. 299 dentate patients with diabetes, who were regular attendants to a diabetic clinic, were selected as the study subjects. Data collection was performed through a clinical dental examination and self-administered structured questionnaire. The questionnaire covered information of the subject s social background, medical history, oral health behaviour and smoking. The clinical dental examinations covered the registration of caries experience (DMFT), community periodontal index (CPI) and plaque index (PI). The intervention provided the adults with diabetes dental health education through a booklet. Reduction in periodontal treatment needs one year after the baseline examination was used as the main outcome. A high prevalence of periodontal pockets among the study population was found; 52% of the participants had periodontal pockets with a pocket depth of 4 to 5 mm and 35% had periodontal pockets with pocket depth of 6 mm or more. The mean of the DMFT index was 12.9 (SD=6.1), being dominated by filled teeth (mean 6.5) and missing teeth (mean 5.0). Oral self-care among adults with diabetes was inadequate and poor oral hygiene was observed in more than 80% of the subjects. The educational oral health promotion decreased periodontal treatment needs more in the study groups than in the control group. The poor periodontal health, poor oral hygiene and insufficient oral self-care observed in this study call for oral health promotion among adult with diabetes. An educational intervention showed that it is possible to promote oral health behaviour and to reduce periodontal treatment needs among adults with diabetes. The simplicity of the model used in this study allows it to be integrated to diabetes programmes in particular in countries with a developing health care system.

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We propose a new self-assembly based strategy for the design of novel lanthanide based luminescent materials. In this approach a europium hydrogel is prepared and sensitization is achieved by doping the gel with pyrene in a non-coordinated fashion.

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Coordination-driven self-assembly of 1,3,5-benzenetricarboxylate (tma; 1) and oxalato-bridged p-cymeneruthenium(II) building block Ru-2(mu-eta(4)-C2O4)(MeOH)(2)(eta(6)-p-cymene)(2)](O3SCF3)(2) (2) affords an unusual octanuclear incomplete prism Ru-8(eta(6)-p-cymene)(8)(tma)(2)(mu-eta(4)-C2O4)(2)(OMe)(4)](O3SCF3)( 2) (3), which exhibits a remarkable shape-selective binding affinity for neutral phenolic compounds via hydrogen-bonding interactions (p-cymene = p-(PrC6H4Me)-Pr-i). Such a binding was confirmed by single-crystal X-ray diffraction analysis using 1,3,5-trihydroxybenzene as an analyte.

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Entrepreneurship, understood as the autonomous, effective pursuit of opportunities regardless of resources, is currently subject to a multitude of interests, expectations, and facilitation efforts. On the one hand, such entrepreneurial agency has broad appeal to individuals in Western market democracies and resonates with their longing for an autonomous, personally tailored, meaningful, and materially rewarding way of life. On the other hand, entrepreneurship represents a tempting and increasingly popular means of governance and policy making, and thus a model for the re-organization of a variety of societal sectors. This study focuses on the diffusion and reception of entrepreneurship discourse in the context of farming and agriculture, where pressures to adopt entrepreneurial orientations have been increasingly pronounced while, on the other hand, the context of farming has historically enjoyed state protection and adhered to principles that seem at odds with aspects of individualistic entrepreneurship discourse . The study presents an interpretation of the psychologically and politically appealing uses of the notion of entrepreneurial agency , reviews the historical and political background of the current situation of farming and agriculture with regard to entrepreneurship, and examines their relationships in four empirical studies. The study follows and develops a social psychological, situated relational approach that guides the qualitative analyses and interpretations of the empirical studies. Interviews with agents from the farm sector aim to stimulate evaluative responses and comments on the idea of entrepreneurship on farms. Analysis of the interview talk, in turn, detects the variety of evaluative responses and argumentative contexts with which the interviewees relate themselves to the entrepreneurship discourse and adopt, use, resist, or reject it. The study shows that despite the pressures towards entrepreneurialism, the diffusion of entrepreneurship discourse and the construction of entrepreneurial agency in farm context encounter many obstacles. These obstacles can be variably related to aspects dealing with the individual agent, the action situation, the characteristics of the action itself, or to the broader social, institutional and cultural context. Many aspects of entrepreneurial agency, such as autonomy, personal initiative and achievement orientation, are nevertheless familiar to farmers and are eagerly related to one s own farming activities. The idea of entrepreneurship is thus rarely rejected outright. The findings highlight the relational and situational preconditions for the construction of entrepreneurial agency in the farm context: When agents demonstrate entrepreneurial agency, they do so by drawing on available and accessed relational resources characteristic of their action context. Likewise, when agents fail or are reluctant to demonstrate entrepreneurial agency, they nevertheless actively account for their situation and demonstrate personal agency by drawing on the relational resources available to them.

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A first comprehensive investigation on the deflagration of ammonium perchlorate (AP) in the subcritical regime, below the low pressure deflagration limit (LPL, 2.03 MPa) christened as regime I$^{\prime}$, is discussed by using an elegant thermodynamic approach. In this regime, deflagration was effected by augmenting the initial temperature (T$_{0}$) of the AP strand and by adding fuels like aliphatic dicarboxylic acids or polymers like carboxy terminated polybutadiene (CTPB). From this thermodynamic model, considering the dependence of burning rate ($\dot{r}$) on pressure (P) and T$_{0}$, the true condensed (E$_{\text{s,c}}$) and gas phase (E$_{\text{s,g}}$) activation energies, just below and above the surface respectively, have been obtained and the data clearly distinguishes the deflagration mechanisms in regime I$^{\prime}$ and I (2.03-6.08 MPa). Substantial reduction in the E$_{\text{s,c}}$ of regime I$^{\prime}$, compared to that of regime I, is attributed to HClO$_{4}$ catalysed decomposition of AP. HClO$_{4}$ formation, which occurs only in regime I$^{\prime}$, promotes dent formation on the surface as revealed by the reflectance photomicrographs, in contrast to the smooth surface in regime I. The HClO$_{4}$ vapours, in regime I$^{\prime}$, also catalyse the gas phase reactions and thus bring down the E$_{\text{s,g}}$ too. The excess heat transferred on to the surface from the gas phase is used to melt AP and hence E$_{\text{s,c}}$, in regime I, corresponds to the melt AP decomposition. It is consistent with the similar variation observed for both the melt layer thickness and $\dot{r}$ as a function of P. Thermochemical calculations of the surface heat release support the thermodynamic model and reveal that the AP sublimation reduces the required critical exothermicity of 1108.8 kJ kg$^{-1}$ at the surface. It accounts for the AP not sustaining combustion in the subcritical regime I$^{\prime}$. Further support for the model comes from the temperature-time profiles of the combustion train of AP. The gas and condensed phase enthalpies, derived from the profile, give excellent agreement with those computed thermochemically. The $\sigma _{\text{p}}$ expressions derived from this model establish the mechanistic distinction of regime I$^{\prime}$ and I and thus lend support to the thermodynamic model. On comparing the deflagration of strand against powder AP, the proposed thermodynamic model correctly predicts that the total enthalpy of the condensed and gas phases remains unaltered. However, 16% of AP particles undergo buoyant lifting into the gas phase in the `free board region' (FBR) and this renders the demarcation of the true surface difficult. It is found that T$_{\text{s}}$ lies in the FBR and due to this, in regime I$^{\prime}$, the E$_{\text{s,c}}$ of powder AP matches with the E$_{\text{s,g}}$ of the pellet. The model was extended to AP/dicarboxylic acids and AP/CTPB mixture. The condensed ($\Delta $H$_{1}$) and gas phase ($\Delta $H$_{2}$) enthalpies were obtained from the temperature profile analyses which fit well with those computed thermochemically. The $\Delta $H$_{1}$ of the AP/succinic acid mixture was found just at the threshold of sustaining combustion. Indeed the lower homologue malonic acid, as predicted, does not sustain combustion. In vaporizable fuels like sebacic acid the E$_{\text{s,c}}$ in regime I$^{\prime}$, understandably, conforms to the AP decomposition. However, the E$_{\text{s,c}}$ in AP/CTPB system corresponds to the softening of the polymer which covers AP particles to promote extensive condensed phase reactions. The proposed thermodynamic model also satisfactorily explains certain unique features like intermittent, plateau and flameless combustion in AP/ polymeric fuel systems.

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A novel universal approach to understand the self-deflagration in solids has been attempted by using basic thermodynamic equation of partial differentiation, where burning mte depends on the initial temperature and pressure of the system. Self-deflagrating solids are rare and are reported only in few compounds like ammonium perchlorate (AP), polystyrene peroxide and tetrazole. This approach has led us to understand the unique characteristics of AP, viz. the existence of low pressure deflagration limit (LPL 20 atm), hitherto not understood sufficiently. This analysis infers that the overall surface activation energy comprises of two components governed by the condensed phase and gas phase processes. The most attractive feature of the model is the identification of a new subcritical regime I' below LPL where AP does not burn. The model is aptly supported by the thermochemical computations and temperature-profile analyses of the combustion train. The thermodynamic model is further corroborated from the kinetic analysis of the high pressure (1-30 atm) DTA thermograms which affords distinct empirical decomposition rate laws in regimes I' and 1 (20-60 atm). Using Fourier-Kirchoff one dimensional heat transfer differential equation, the phase transition thickness and the melt-layer thickness have been computed which conform to the experimental data.

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The role of self accomodation of the different mertensite variants controlling the morphologies of the Zr---2.5wt%Nb alloy martensite has been examined. Three distinct types of grouping of martensite variants have been found to be predominantly present. Crystallographic descriptions of these groups have been provided and the degrees of self accomodation for these have been estimated and compared with those corresponding to other possible variant groupings around the symmetry axes of the parent phase. The frequently observed 3-variant group, which shows an “indentation mark” morphology when viewed along left angle bracket111right-pointing angle bracketβ directions in the transmission electron microscope, has been seen to have the highest degree of self accomodation amongst the cases considered. Based on the observations made, a growth sequence leading to the formation of the final martensitic structure has been proposed.

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The design and preparation of novel M3L2 trigonal cages via the coordination-driven self-assembly of preorganized metalloligands containing octahedral aluminum(III), gallium(III), or ruthenium(II) centers is described. When tritopic or dinuclear linear metalloligands and appropriate complementary subunits are employed, M3L2 trigonal-bipyramidal and trigonal-prismatic cages are self-assembled under mild conditions. These three-dimensional cages were characterized with multinuclear NMR spectroscopy (H-1 and P-31) and high-resolution electrospray ionization mass spectrometry. The structure of one such trigonal-prismatic cage, self-assembled from an arene ruthenium metalloligand, was confirmed via single-crystal X-ray crystallography. The fluorescent nature of these prisms, due to the presence of their electron-rich ethynyl functionalities, prompted photophysical studies, which revealed that electron-deficient nitroaromatics are effective quenchers of the cages' emission. Excited-state charge transfer from the prisms to the nitroaromatic substrates can be used as the basis for the development of selective and discriminatory turn-off fluorescent sensors for nitroaromatics.

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An organic-inorganic composite material is obtained by self-assembly of 2,3-didecyloxy-anthracene (DDOA), an organogelator of butanol, and organic-capped ZnO nanoparticles (NPs). The ligand 3, 2,3-di(6-oxy-n-hexanoic acid)-anthracene, designed to cap ZnO and interact with the DDOA nanofibers by structural similarity, improves the dispersion of the NPs into the organogel. The composite material displays mechanical properties similar to those of the pristine DDOA organogel, but gelates at a lower critical concentration and emits significantly less, even in the presence of very small amounts of ZnO NPs. The ligand 3 could also act as a relay to promote the photo-induced quenching process.

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The constructional details of an 18-bit binary inductive voltage divider (IVD) for a.c. bridge applications is described. Simplified construction with less number of windings, interconnection of winding through SPDT solid state relays instead of DPDT relays, improves reliability of IVD. High accuracy for most precision measurement achieved without D/A converters. The checks for self consistency in voltage division shows that the error is less than 2 counts in 2(18).

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Design and synthesis of three novel 2 + 2] self-assembled molecular rectangles 1-3 via coordination driven self-assembly of predesigned Pd(II) ligands is reported. 1,8-Diethynylanthracene was assembled with trans-Pd(PEt3)(2)Cl-2 in the presence of CuCl catalyst to yield a neutral rectangle 1 via Pd-C bond formation. Complex 1 represents the first example of a neutral molecular rectangle obtained via C-Pd coordination driven self-assembly. A new Pd-2(II) organometallic building block with 180 degrees bite-angle 1,4-bistrans-(ethynyl)Pd(PEt3)(2)(NO3)] benzene (M-2) containing ethynyl functionality was synthesized in reasonable yield by employing Sonagashira coupling reaction. Self-assembly of M-2 with two organic clip-type donors (L-2-L-3) afforded 2 + 2] self-assembled molecular rectangles 2 and 3, respectively L-2 = 1,8-bis(4-pyridylethynyl) anthracene; L-3 = 1,3-bis(3-pyridyl) isophthalamide]. The macrocycles 1-3 were fully characterized by multinuclear NMR and ESI-MS spectroscopic techniques, and in case of 1 the structure was unambiguously determined by single crystal X-ray diffraction analysis. Incorporation of Pd-ethynyl bonds helped to make the assemblies p-electron rich and fluorescent in nature. Complexes 1-2 showed quenching of fluorescence intensity in solution in presence of nitroaromatics, which are the chemical signatures of many commercially available explosives.