2,673 research outputs found
Excess portal venous long-chain fatty acids induce syndrome X via HPA axis and sympathetic activation
We tested the hypothesis that excessive portal venous supply of long-chain fatty acids to the liver contributes to the development of insulin resistance via activation of the hypothalamus-pituitary-adrenal axis (HPA axis) and sympathetic system. Rats received an intraportal infusion of the long-chain fatty acid oleate (150 nmol/min, 24 h), the medium-chain fatty acid caprylate, or the solvent. Corticosterone (Cort) and norepinephrine (NE) were measured as indexes for HPA axis and sympathetic activity, respectively. Insulin sensitivity was assessed by means of an intravenous glucose tolerance test (IVGTT). Oleate infusion induced increases in plasma Cort (Δ = 13.5 ± 3.6 µg/dl; P < 0.05) and NE (Δ = 235 ± 76 ng/l; P < 0.05), whereas caprylate and solvent had no effect. The area under the insulin response curve to the IVGTT was larger in the oleate-treated group than in the caprylate and solvent groups (area = 220 ± 35 vs. 112 ± 13 and 106 ± 8, respectively, P < 0.05). The area under the glucose response curves was comparable [area = 121 ± 13 (oleate) vs. 135 ± 20 (caprylate) and 96 ± 11 (solvent)]. The results are consistent with the concept that increased portal free fatty acid is involved in the induction of visceral obesity-related insulin resistance via activation of the HPA axis and sympathetic system.
The changing logic of Japanese employment practices: A firm-level analysis of four industries.
YesIn previous decades, the perception of Japan¿s employment practices has been strongly intertwined with its economic fortunes. From the 1970s, Japan¿s employment practices came to be seen as one of the cornerstones of its economic success. However, this perception changed, albeit with a substantial delay, when the economy proved incapable of returning to its former path of growth after the `bubble¿ burst at the end of the 1980s. Like so many of its economic institutions, the employment practices became the subject of substantial criticism in a debate on the revitalisation of Japan¿s economy. This study takes its position within this debate by discussing the likelihood, character, and economic consequences of change. Environmental changes, like the ageing of the population and the substantial decrease in economic growth, require Japanese firms to adapt their human resource management. However, the embeddedness of national practices limits the scope of firms to make these adjustments; and change is determined by the dialectics between their strategies and existing practices. The firm, as an institution, thus experiences the impact of both the embedded employment practices and the economic impact of environmental changes. Accordingly, it is at the centre of this study. Theories of the firm are used to discuss the contribution of employment practices on efficiency, capabilities, and competitive strength. Case-studies from four different industries ¿ automobile, electronics, construction, and retailing ¿ describe the adaptations made by individual firms. Subsequently, these findings constitute the basis for a discussion of industry-specific employment practices and provide an answer to whether developments such as the rise in performance-based pay and labour mobility have altered the logic of Japanese employment practices
‘Palliatieve sedatie – omdat de patiënt dat wil’
Article / Letter to editorInstituut voor Publiekrech
3-Dimensional Tuning of an Atomically Defined Silicon Tunnel Junction
A requirement for quantum information processors is the in-situ tunability of
the tunnel rates and the exchange interaction energy within the device. The
large energy level separation for atom qubits in silicon is well suited for
qubit operation but limits device tunability using in-plane gate architectures,
requiring vertically separated top-gates to control tunnelling within the
device. In this paper we address control of the simplest tunnelling device in
Si:P, the tunnel junction. Here we demonstrate that we can tune its conductance
by using a vertically separated top-gate aligned with +-5nm precision to the
junction. We show that a monolithic 3D epitaxial top-gate increases the
capacitive coupling by a factor of 3 compared to in-plane gates, resulting in a
tunnel barrier height tunability of 0-186meV. By combining multiple gated
junctions in series we extend our monolithic 3D gating technology to implement
nanoscale logic circuits including AND and OR gates
Monitoring the salt marsh vegetation and flora of the Baixo Vouga Lagunar (Ria of Aveiro, Portugal)
El carácter transicional de la Ría de Aveiro le confiere una riqueza florística singular, integrando comunidades vegetales típicas de las
regiones Eurosiberiana y Mediterránea. La implantación del Proyecto Desenvolvimento Agrícola do Vouga (PDAV) va a provocar una
modificación de las tasas de encharcamiento y una reducción gradual de la salinidad, factores ecológicos determinantes para muchas de las
comunidades halófilas y helofíticas. El presente trabajo pretende contribuir a un mejor conocimiento de la tipología de la vegetación local, que
sirva como base para desarrollar un programa de monitorización adecuado que detecte las alteraciones en los patrones espacio- temporales
de la vegetación de los sistemas húmedos. Teniendo como objetivo seleccionar los puntos de muestreo donde instalar las parcelas
permanentes de monitorización, se realizó una caracterización de la flora y la vegetación a través de trece transectos utilizando una
aproximación simplificada al método de Braun- Blanquet. Una vez identificados los tipos de vegetación - en función de su composición
florística, corología y ecología - fueron seleccionados al azar inventarios representativos de cada tipo, en los que han sido instaladas dichas
parcelas.The transitional
biogeographic character of the Ria de Aveiro lagoon area confers it a singular floristic richness, integrating plant communities typical for the
Eurosiberian as well as Mediterranean Region. The implementation of the Agricultural Development Plan of the Lower Vouga area (PDAV) in
the near future is expected to result in noticeable changes in the tidal submersion regime and a gradual reduction of salinity levels, which are
determining ecological factors for many of the halophytic and helophytic plant communities. The present work pretends to contribute to a
better knowledge of the local vegetation types and, thereby, to the implementation of an adequate monitoring programme for detecting
changes in the spatio-temporal vegetation patterns of the wetlands. With the objective to select the locations for the installation of permanent
quadrats, the vegetation of the wetlands was described along 13 transects using a simplified Braun-Blanquet approach. A total of 24 local
vegetation types were recognised, 23 of which were selected for the current monitoring programme
Reversible Diffusion-Limited Reactions: "Chemical Equilibrium" State and the Law of Mass Action Revisited
The validity of two fundamental concepts of classical chemical kinetics - the
notion of "Chemical Equilibrium" and the "Law of Mass Action" - are re-examined
for reversible \textit{diffusion-limited} reactions (DLR), as exemplified here
by association/dissociation reactions. We consider a
general model of long-ranged reactions, such that any pair of particles,
separated by distance , may react with probability , and
any may dissociate with probability into a geminate
pair of s separated by distance . Within an exact analytical
approach, we show that the asymptotic state attained by reversible DLR at is generally \textit{not a true thermodynamic equilibrium}, but rather
a non-equilibrium steady-state, and that the Law of Mass Action is invalid. The
classical picture holds \text{only} in physically unrealistic case when
for any value of .Comment: 4 page
Possible experiment to check the reality of a nonequilibrium temperature
An experiment is proposed to check the physical reality of a nonequilibrium absolute temperature previously proposed from theoretical grounds in the framework of extended irreversible thermodynamics
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