148 research outputs found
Investigating the roles of F-ATP synthase subunits e and g in Drosophila melanogaster
No full textDifferently from yeast and mammals, Drosophila melanogaster does not show a mitochondrial permeability transition (PT), a process caused by the opening of the so-called permeability transition pore (PTP). The PTP is defined as a Ca2+-activated, high-conductance and unselective channel with a maximal conductance of 1.2 nS that allows ions and solutes up to 1.5 kDa to equilibrate across the inner membrane. PTP openings play a role in both Ca2+ homeostasis and cell death initiation. Conversely, Drosophila PTP appears to be specialized and operate uniquely as a selective Ca2+- release channel (CrC), that does not induce mitochondrial swelling and cell death. ATP synthase was recently demonstrated to mediate the PT in mammals and yeast and to generate a peculiar 53 pS channel in Drosophila that could represent the CrC. Genetic studies showed that the ablation of ATP synthase “accessory subunits” e and g dramatically affects PT occurrence in mammals and yeast, suggesting a primary role of these small proteins in PTP formation. To shed light on the roles of the two subunits in Drosophila, we generated knock-down (KD) lines for genes encoding either subunit e (ATPsynE) or g (ATPsynG) of ATP synthase. In vivo ubiquitous downregulation of each subunit causes a dramatic arrest in fly development at larval stage, impairs the dimerization and oligomerization states of ATP synthase and decreases mitochondrial respiration, yet the total amount of ATP is unaltered. Strikingly, the sensitivity to Ca2+ is decreased in both ATPsynE and ATPsynG KD mitochondria, which require higher matrix Ca2+ loads (1.5-fold and 3-fold, respectively) to induce the CrC. However, studies on Ca2+ dynamics in vivo revealed no major differences in mitochondrial basal Ca2+ levels, as well as in Ca2+ transients in motor neurons of flies carrying the specific downregulation of these two subunits in these cells, possibly due to compensatory mechanisms. Importantly, downregulation of both ATPsynE and ATPsynG only in muscle tissue leads to the development of adult flies which show compromised assembly and stability of the F-ATP synthase in muscle, characterized by decreased levels of oligomers and dimers, but also monomers and the accumulation of vestigial forms and of the F1 sector. Surprisingly, mitochondrial respiration is not affected, and the total ATP levels are comparable to those of control flies, although mitochondria of both KD models display altered cristae morphology. Altogether, our results confirm a key role of these two proteins in the formation of Drosophila channel and suggest that the phenotype of KD flies is not entirely due to bioenergetic defects but may also partially arise from a CrC-related Ca2+ dysregulation
The micro-foundations of Corporate Purpose:Performance management in dynamic environments
No full textThis paper examines the micro-foundations of ‘corporate purpose’, that is the enduring reason for being of a corporation in relation to society. While the relevance of corporate purpose has been widely recognized, its practical enactment by managers at the operating level remains problematic, particularly in dynamic environments. By relying upon the field study of a leading Italian group in the food industry, and the literature on the micro-foundations of institutions, we explore the role of a performance management system (PMS) in mobilizing corporate purpose in specific practical situations at the management level, while the organization faces the demands coming from the external environment. We show that the PMS can be drawn upon by managers as a set of tools and practices through which purpose is situated at the micro-level into actions, decisions, and material artefacts that come together in a ‘social situation’. Here, the PMS enables managers to recognize a ‘situation’ for enacting different aspects of purpose through interactions, filling it with evolving meanings, while sustaining its connections with global development needs
Seminari di storia della lettura e della ricezione, tra Italia e Francia, nel Cinquecento. Vol. 4
No full textQuattro piste d’indagine si rivolgono in questo volume alle manifestazioni letterarie della danza simbolica della carole (E. Muzzolon), ai primi volgarizzamenti di tragedie classiche nel Cinquecento francese (F. Fassina), alla produzione tragica, più in particolare, all’epoca delle guerre di religione (M. Meere), e poi, con un’incursione della nostra Collana verso il Seicento, ad un sentimento del tragico, letto nel senso del paradosso, in Pascal (A. Frigo). Elena Muzzolon lavora su testi medievali e rinascimentali per mettere in luce il valore allegorico, letterario e magico della danza in cerchio. Filippo Fassina indaga l’obscuritas del testo drammatico antico, così come si presentava nel Cinquecento agli umanisti, nel loro sforzo di comprensione della tragedia classica. Michael Meere analizza tragedie militanti e politiche, come in particolare Le Guysien di Belyard. Alberto Frigo legge le Pensées tessendo ipotesi sul senso e la funzione del sentimento, a partire dai contesti originali visti come la carta di una geografia pascaliana
Locke o Spinoza: un punto di eresia
No full textRelying on his previous inquiries, the author discusses theories of “consciousness” which were elaborated almost simultaneously by Locke and Spinoza, as a reaction against the Cartesian doctrine of self-certainty. Because of their remarkable analogies and their sharp antithesis, they illustrate a “point of heresy” which, even today, intrinsically divides any project of framing a “psychology” or “philosophy of mind
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Using the balanced scorecard framework /
No full text"... explains the balanced scorecard framework. Since its introduction in the early 1990s, the balanced scorecard framework has become a standard strategy execution and performance measurement system for many for-profit companies as well as for non-profit organizations and public sector entities. Scholars, including the author of this portfolio, Dr. Mark L. Frigo, have continued to refine this framework with cutting-edge managerial and accounting concepts.
Control vs. Creativity
No full textThey’re eternal questions in business: Does management control
kill creativity? How can organizations manage efficiency within
innovating processes? Do control and creativity call for a balance
within processes of innovation—or is balancing a bad
idea? The answers to these questions are probably bedeviling
entrepreneurs and executives everywhere around the world.
While a controlled working environment has its advantages, too
much control can hamper the creativity, as well as the ability to
innovate, that leads to new products and to growth and profitability.
The article addresses these issues by offering
insights from a medium-sized company in the fashion industry
that has used formal and informal control tools to manage its
need for both standardization and innovation
Linking governance to strategy: the role of the Finance Organization
No full textThe capabilities, skills, and responsibilities required of finance professionals have changed significantly over the last
decade. No longer limited to tracking financial results and rigorous financial reporting, finance experts are increasingly
required to support strategic decision making, operation efficiency, and value creation and to combine solid
accounting skills with knowledge of the business, leadership abilities, and management expertise. And such capabilities
still aren’t enough.
In 2002, the Sarbanes-Oxley Act (SOX) in the U.S. directly impacted the finance organization (and the CFO) by
introducing new responsibilities for the trustworthiness and reliability of financial reports (Section 302) and new
requirements for internal controls (Section 404). Such emerging issues and new responsibilities call for a redefinition
of the role of the finance organization in the governance process. Using the case of GE Oil & Gas, we suggest that
finance professionals can be much more directly involved within the corporate governance framework by playing an
active role in translating governance principles into strategic decision making and strategic performance management
systems. Although we include examples from GE Oil & Gas to build our argument, many of the issues we discuss
are relevant and applicable for the entire GE organization
Fausto Sozzini, la mortalità d’Adamo e la teologia moderna
No full textFausto Sozzini, Adam's Mortality and Early Modern Theology. In his dispute with Francesco Pucci, Fausto Sozzini argues that man was not created immortal but, being by nature subject to death, he could be made perpetually immune only through divine grace, which was a gift not included in his creation. It has thus been suggested that the Pucci-Sozzini querelle should be read as an expression of the broader debate that opposed the two 'souls' of modern theology, that is the Thomistic and the Augustinian. By reconstructing the late medieval theological debate on the mortality of Adam in the condition of innocence, the Author tries to show that Sozzini's theses are greatly indebted to Duns Scotus' criticisms of Thomas Aquinas
Sympathetic denervation-induced changes in G protein expression in enteric neurons of the guinea pig colon
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