1,466 research outputs found
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Succession narratives in family business: the case of Alessi
One of the most significant challenges facing family firms is how to successfully manage succession from one generation of leaders to the next. In this paper, we contribute to existing understandings of this complex and difficult process by exploring how successors use family business succession narratives to legitimate their succession. Building on a case study of Alessi, a family-owned Italian design firm, we draw on the literature on organizational narratives to develop a framework for understanding family business succession narratives and present a typology of some of the narrative strategies that can be used during succession. We conclude with a discussion of the theoretical and practical ramifications of a narrative view of succession in family firms
Dimorfismo Sexual na Hipertrofia Ventricular Esquerda e Função cardíaca de Ratos Espontaneamente Hipertensos: O Papel da Atividade da Enzima Conversora de Angiotensina (ECA) e ECA2 no Ventrículo Esquerdo e no Rim
Os hormônios sexuais podem ser um fator-chave para as diferenças entre os sexos observadas nos índices e na gravidade das doenças renais e cardiovasculares. Este é o primeiro estudo a relacionar função cardíaca, efeitos tróficos e status hormonal com a atividade tecidual de 2 importantes e antagônicos componentes do SRA, ECA e ECA2, no rim e ventrículo esquerdo (VE), de ratos SHRs. Ratos SHR machos (M) e fêmeas (F), 12 semanas de idade, fêmea (F) e macho (M) foram divididos em dois grupos experimentais (n = 7 em cada grupo): Sham (S) e Gonadectomizado (G). Cinquenta dias após gonadectomia, avaliamos: hipertrofia ventricular esquerda, dP/dt + e dP/dt -, atividade da ECA (aECA) e atividade da ECA2 (aECA2) no rim e no VE e Western Blot do receptor AT1, SERCA2a, fosfolambam (PLB) e razão da PLB/SERCA2a. Os machos SHR exibiram maior da aECA e aECA2, maior hipertrofia ventricular comparado as fêmeas. A orquiectomia reduziu aECA e a hipertrofia ventricular, enquanto a ovariectomia aumentou essas variáveis. A função cardíaca nos machos do grupo sham, apresentaram menor dP/dt+ (SM: 5140 ± 259 mmHg vs. SF: 6485 ± 178 mmHg) e menor dP/dt- do que as fêmeas (MS: -3.717 ± 129 mmHg vs. FS: -5.250 ± 115 mmHg). A gonadectomia, inverteu os resultados, as fêmeas tiveram redução da dP/dt+ (GM = 6.728 ± 177 mmHg vs GF: 5453 ± 229 mmHg) e dP/dt- (SM: -4.851 ± 290 mmHg vs GF = -3.913 ± 136 mmHg). Não foi observada diferença na SERCA2a, nem entre grupo sham, nem entre o grupo gonadectomizado, enquanto que o PLB e do PLB/ SERCA2a, somente a ovariectomia promoveu aumento nestas duas variáveis. Na expressão do receptor AT1, os machos exibiram maior expressão que as fêmeas, e gonadectomia reduziu nos machos e eliminou a diferença. A ovariectomia conduziu a aumento da hipertrofia cardíaca, maior aECA2, expressão PLB e da razão PLB/SERCA2a, e agravamento de variáveis hemodinâmicas, enquanto que nos machos, a remoção de testosterona teve efeito oposto. No rim, as fêmeas SHR apresentaram maior aECA e aECA2. A gonadectomia não mudou a ECA. Neste modelo, no rim. A ECA2 parece ter maior participação na modulação local que a ECA. A avaliação de dimorfismo sexual dos componentes do SRA pode contribuir para o desenvolvimento continuado de intervenções terapêuticas eficazes para as doenças cardiovasculares.
Abstract
There is growing interest in sex differences and RAS components; however, whether gender influences cardiac angiotensin I-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2) activity is still unknown. In the present work we determined the relationship between ACE and ACE2 activity on kidney and heart, left ventricular function and gender in spontaneously hypertensive rats (SHRs). Twelve-week-old female (F) and male (M) SHRs were divided into 2 experimental groups (n = 7 in each group): sham (S) and gonadectomized (G). Fifty days after gonadectomy, we measured positive and negative first derivatives (dP/dt+ and dP/dt-), hypertrophy (morphometric analysis) and ACE and ACE2 catalytic activity in kidney and LV (left ventricle). Expression of calcium handling proteins and AT1 receptor was measured by western blot analysis. Male rats exhibited higher cardiac ACE and ACE2 activity as well as hypertrophy compared to female rats. Orchiectomy reduced ACE activity and hypertrophy, while ovariectomy increased these variables. In relation to cardiac function, the sham group, male to compared female rats, had a lower +dP/dt (MS: 5140 ± 259 mmHg vs. FS: 6485 ± 178 mmHg) and lower -dP/dt (MS: -3.717 ± 129 mmHg vs. FS: -5.250 ± 115 mmHg) than the female sham group. After gonadectomy, the results inverted such that they were increased in males and reduced in female rats in dP/dt+ (GM = 6.728 ± 177 mmHg vs FG: 5453 ± 229 mmHg) and dP/dt- (SM: -4.851 ± 290 mmHg vs GF = -3.913 ± 136 mmHg). No difference among the groups in the SERCA2a protein expression was observed. The gonadectomy increased protein expression of PLB and the PLB to SERCA2a ratio in female rats, but did not alter in male rats. In conclusion, the ovariectomy leads to increased cardiac hypertrophy, ACE2 activity, PLB expression and PLB to SERCA2a ratio, and worsening of hemodynamic variables, wher-eas in males the removal of testosterone has the opposite effect in RAS components.
Our data suggest that sex steroids are of great importance for both female and male SHRs in influencing cardiac function and in regulating the RAS in kidney and LV. In our study, in LV the withdrawal of estrogen in females led to increased cardiac hypertrophy, increased ACE2 activity, PLB expression and PLB to SERCA2a ratio, what could be related to worsening of hemodynamic variables. In males, however, the removal of testosterone had the opposite effect in RAS components. The increase in ACE2 activity after ovariectomy and the reduction after orchiectomy seems to be occurring to counterbalance the observed changes. In the kidney, in females the activity of ACE and ACE2 was higher, favoring the balance between these two important components of the RAS. In the male, conversely, lower levels of ACE and ACE2 favoring the imbalance. ACE, although important, has not changed with the hormonal status, so that in this model, the ACE2 have greater involvement in local modulation of these components. Certainly, the assessment of sexual dimorphism of the components of the RAS can help the continued development of effective therapeutic interventions for cardiovascular diseases
A Method to Polarize Stored Antiprotons to a High Degree
Polarized antiprotons can be produced in a storage ring by spin--dependent
interaction in a purely electron--polarized hydrogen gas target. The polarizing
process is based on spin transfer from the polarized electrons of the target
atoms to the orbiting antiprotons. After spin filtering for about two beam
lifetimes at energies MeV using a dedicated large acceptance
ring, the antiproton beam polarization would reach . Polarized
antiprotons would open new and unique research opportunities for spin--physics
experiments in interactions
A Goal-based Framework for Contextual Requirements Modeling and Analysis
Requirements Engineering (RE) research often ignores, or presumes a uniform nature of the context in which the system operates. This assumption is no longer valid in emerging computing paradigms, such as ambient, pervasive and ubiquitous computing, where it is essential to monitor and adapt to an inherently varying context. Besides influencing the software, context may influence stakeholders' goals and their choices to meet them. In this paper, we propose a goal-oriented RE modeling and reasoning framework for systems operating in varying contexts. We introduce contextual goal models to relate goals and contexts; context analysis to refine contexts and identify ways to verify them; reasoning techniques to derive requirements reflecting the context and users priorities at runtime; and finally, design time reasoning techniques to derive requirements for a system to be developed at minimum cost and valid in all considered contexts. We illustrate and evaluate our approach through a case study about a museum-guide mobile information system
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The cultural side of value creation
The question of how organizations create value has become a central question for understanding inter-firm competition and performance differentials. Much of the work on the topic emphasizes the importance of technological innovation for improving operational efficiency and/or product functionality . Accordingly, much of the work in the area has focused on understanding the development of technological capabilities and the dynamics of competition among different technologies.
Whereas this line of research has contributed greatly to our understanding of value creation through technology performance improvement, it has also left unexplored the strategies for differentiating products on the basis of their cultural significance. Yet, research in a wide variety of disciplines ranging from anthropology, to cultural sociology, and consumer behavior shows that consumers value products not only for their functional and technical performance, but also for their cultural meanings. The infusion of products with cultural meanings enables consumers to use these products to make statements about their personal and social identity and status. It is therefore well understood that consumers derive value not only from what products do (functional value), but also from what they signify in a given social group (symbolic value).
While strategy scholars recognize that product meanings are a source of differentiation and generate price premia (Porter, 1980), they also tend to view the activities that generate them – e.g. branding – as a part of the marketing strategy of the firm. More generally, strategy research has been criticized for its reluctance to delve into the demand side of value-creation. Rooted in disciplinary assumptions about atomistic consumers with idiosyncratic preferences, strategy researchers view demand as largely exogenous and ignore its cultural embeddedness in social conventions that define the cultural meanings of objects and shape consumption choices. As a result, they have given limited attention to the question of how firms can strategically manage the symbolic value of their products.
In this paper we propose a cultural perspective on value creation that can direct strategic organization research toward the systematic investigation of how producers engage with the cultural meaning systems that supply frameworks for interpretation and valuation of goods. To guide research in this direction we first discuss how products acquire cultural significance and then outline three core implications of these ideas for the strategy and organization of firms. First, we discuss how recognizing the cultural significance of products shifts attention from technological innovation that alters product functionality to cultural innovation that alters their cultural significance. Second, we explain the need to develop distinct cultural resources that enable firms to identify and exploit opportunities for cultural innovation. Third, we draw attention to the need for cultural intent defined as developing an explicit strategy for utilizing cultural resources to achieve specific cultural positioning for the firm’s products
Interference Study of the chi_c0 (1^3P_0) in the Reaction Proton-Antiproton -> pi^0 pi^0
Fermilab experiment E835 has observed proton-antiproton annihilation
production of the charmonium state chi_c0 and its subsequent decay into pi^0
pi^0. Although the resonant amplitude is an order of magnitude smaller than
that of the non-resonant continuum production of pi^0 pi^0, an enhanced
interference signal is evident. A partial wave expansion is used to extract
physics parameters. The amplitudes J=0 and 2, of comparable strength, dominate
the expansion. Both are accessed by L=1 in the entrance proton-antiproton
channel. The product of the input and output branching fractions is determined
to be B(pbar p -> chi_c0) x B(chi_c0 -> pi^0 pi^0)= (5.09 +- 0.81 +- 0.25) x
10^-7.Comment: 4 pages, 4 figures, Accepted by PRL (July 2003
Precision measurements of the total and partial widths of the psi(2S) charmonium meson with a new complementary-scan technique in antiproton-proton annihilations
We present new precision measurements of the psi(2S) total and partial widths
from excitation curves obtained in antiproton-proton annihilations by Fermilab
experiment E835 at the Antiproton Accumulator in the year 2000. A new technique
of complementary scans was developed to study narrow resonances with
stochastically cooled antiproton beams. The technique relies on precise
revolution-frequency and orbit-length measurements, while making the analysis
of the excitation curve almost independent of machine lattice parameters. We
study the psi(2S) meson through the processes pbar p -> e+ e- and pbar p ->
J/psi + X -> e+ e- + X. We measure the width to be Gamma = 290 +- 25(sta) +-
4(sys) keV and the combination of partial widths Gamma_e+e- * Gamma_pbarp /
Gamma = 579 +- 38(sta) +- 36(sys) meV, which represent the most precise
measurements to date.Comment: 17 pages, 3 figures, 3 tables. Final manuscript accepted for
publication in Phys. Lett. B. Parts of the text slightly expanded or
rearranged; results are unchange
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