1,254 research outputs found

    Bringing tasks back in: an organizational theory of resource complementarity and partner selection

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    To progress beyond the idea that the value of inter-firm collaboration is largely determined by the complementarity of the resources held by partners, we build a theoretical framework that explains under which conditions a set of resources or capabilities can be considered as complementary and resulting in superior value creation. Specifically, we argue that the tasks that an inter-firm collaboration has to perform determine complementarities, and that complementarities arise from similar and dissimilar resources alike. We capture this relationship in the concept of task resource complementarity. Further, we examine factors that impact on the relevance of this construct as a predictor of partner selection. Finally, we discuss which implications arise for a theory of the firm when tasks are explicitly incorporated into the conceptualization of resource complementarity

    Lorentz Violating Inflation

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    We explore the impact of Lorentz violation on the inflationary scenario. More precisely, we study the inflationary scenario in the scalar-vector-tensor theory where the vector is constrained to be unit and time like. It turns out that the Lorentz violating vector affects the dynamics of the chaotic inflationary model and divides the inflationary stage into two parts; the Lorentz violating stage and the standard slow roll stage. We show that the universe is expanding as an exact de Sitter spacetime in the Lorentz violating stage although the inflaton field is rolling down the potential. Much more interestingly, we find exact Lorentz violating inflationary solutions in the absence of the inflaton potential. In this case, the inflation is completely associated with the Lorentz violation. We also mention some consequences of Lorentz violating inflation which can be tested by observations.Comment: 7 pages, 1 figur

    Hawking Radiation from Fluctuating Black Holes

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    Classically, black Holes have the rigid event horizon. However, quantum mechanically, the event horizon of black holes becomes fuzzy due to quantum fluctuations. We study Hawking radiation of a real scalar field from a fluctuating black hole. To quantize metric perturbations, we derive the quadratic action for those in the black hole background. Then, we calculate the cubic interaction terms in the action for the scalar field. Using these results, we obtain the spectrum of Hawking radiation in the presence of interaction between the scalar field and the metric. It turns out that the spectrum deviates from the Planck spectrum due to quantum fluctuations of the metric.Comment: 35pages, 4 figure

    Fit for the task: complementarity, asymmetry, and partner selection in alliances

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    Most existing theories of relationship formation imply that organizations establish ties to procure complementary resources, and that doing so adroitly generates relational rents. While this entails a responsibility for organizations to recognize and harness complementarity, most theories struggle with ambiguity around the concept of resource complementarity, neglect its power implications, and rely on rules-of-thumb that assign no role to managers' intentions. To explain the formation of ties that successfully combine critical resources, we propose that a positive interplay among resources only exists insofar as organizations use task requirements to guide their combination. As such, a well-matched tie is one that manages task resource interdependence while offsetting imbalances in task-related resources. We test our theory on project-based, inter-organizational partnerships for public construction in Italy. We find that: (1) The probability of tie formation increases with the quality of the match between the task and actors' resources; (2) There are two distinct, task-related dimensions along which this happens: depth and scope; (3) The effect of these dimensions dwarfs the effect found by measures that assess complementarity irrespective of task; and (4) The probability of tie formation decreases when a task calls for resources that potential partners possess in unequal amounts

    Angle-dependent magnetoresistance in the weakly incoherent interlayer transport regime

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    We present comparative studies of the orientation effect of a strong magnetic field on the interlayer resistance of α\alpha-(BEDT-TTF)2_2KHg(SCN)4_4 samples characterized by different crystal quality. We find striking differences in their behavior which is attributed to the breakdown of the coherent charge transport across the layers in the lower quality sample. In the latter case, the nonoscillating magnetoresistance background is essentially a function of only the out-of-plane field component, in contradiction to the existing theory.Comment: 4 pges, 3 figure

    59Co-NMR Knight Shift of Superconducting Three-Layer NaxCoO2.yH2O

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    The superconducting state of NaxCoO2.yH2O with three CoO2 layers in a unit cell has been studied by 59Co-NMR. The Knight shift measured for a peak of the NMR spectra corresponding to the external magnetic field H along one of the principal directions within the CoO2 plane, exhibits a rapid decrease with decreasing temperature T below the superconducting transition temperature Tc, indicating that the spin susceptibility is suppressed in the superconducting phase, at least, for this field direction. Because differences of the superconducting properties are rather small between this three-layer NaxCoO2.yH2O and previously reported NaxCoO2.yH2O with two CoO2 layers within a unit cell, the present result of the Knight shift studies indicates that the Cooper pairs of the former system are in the singlet state as in the latter, for which the spin susceptibility is suppressed for both directions of H parallel and perpendicular to the CoO2 plane.Comment: 5 page

    Primary cutaneous alk positive anaplastic large cell lymphoma in a melanoma patient

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    Primary cutaneous anaplastic large cell lymphoma (PCALCL) is a raresubset of CD30+ lymphoproliferative disorder, characterized by the presenceof large anaplastic cells, which express CD30, CD2, CD3, CD4, and CD5. A 62 year-old male patient presented to our Institute with a history of a fastgrowing and pinkish-brown asymptomatic cutaneous nodule. His medical past history was positive for a malignant melanoma (MM) of the abdomen (0.7 mm Breslow thickness; pT1a). Histologically the lesion showed a diffuse infiltrate consisting in cohesive sheets of large cells with anaplastic morphology with a kidney-shaped nucleus, also known as hallmark cells. Immunohistochemical studies revealed a CD30 expression, and a positivity to perforin and anaplastic lymphoma kinase (ALK). The laboratory and instrumental investigations were all normal and a final diagnosis of PCALCL was made. The patient showed a good response to radiotherapy. Usually PCALCL shares with systemic anaplastic large cell lymphoma (ALCL) the presence of neoplastic CD30+ large T cells, but lack ALK translocations and protein expression. However, the detection of ALK expression in PCALCL should be considered highly suspicious of a cutaneous manifestation of an underlying systemic disease (not detected in our patient). We recommend to exclude a systemic involvement in this kind of disease, with a strict follow-up, especially in patients with double malignancies

    3+1 Approach to the Long Wavelength Iteration Scheme

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    Large-scale inhomogeneities and anisotropies are modeled using the Long Wavelength Iteration Scheme. In this scheme solutions are obtained as expansions in spatial gradients, which are taken to be small. It is shown that the choice of foliation for spacetime can make the iteration scheme more effective in two respects: (i) the shift vector can be chosen so as to dilute the effect of anisotropy on the late-time value of the extrinsic curvature of the spacelike hypersurfaces of the foliation; and (ii) pure gauge solutions present in a similar calculation using the synchronous gauge vanish when the spacelike hypersurfaces have extrinsic curvature with constant trace. We furthermore verify the main conclusion of the synchronous gauge calculation which is large-scale inhomogeneity decays if the matter--considered to be that of a perfect-fluid with a barotropic equation of state--violates the strong-energy condition. Finally, we obtain the solution for the lapse function and discuss its late-time behaviour. It is found that the lapse function is well-behaved when the matter violates the strong energy condition.Comment: 21 pages, TeX file, already publishe
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