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The variation management and product quality processes are important tasks to guarantee the assemblability of the systems, the scrap reduction and to avoid delays on production and launching. The compound of activities in Geometric Dimensioning and Tolerancing (GD&T) are necessary, especially in the early design stages, to take into account variations of different nature and from different sources. In this paper, an approach for considering the loading conditions in a polyhedral-based approach in tolerancing design is presented. The load boundary conditions are represented as additional displacement restrictions in the deviation space. The restrictions imposed by the physical limits of a system, the ones coming from the loading conditions and the degrees of freedom (DoF) can be all described and represented with a single polyhedron operand. The approach is illustrated using a simplified 2-D model for both ideal and non-ideal geometry. A 3-D model describing an unilateral contact is presented as a case study using Skin Model Shapes. By taking into account geometrical form defects, external loads, and the kinematics of the system, its sensitivity to variations can be reduced even from early design stages.
We examine the relationship between transformational leadership and job improvement behaviors by considering the moderating effect of leader extraversion and the mediating role of employee vitality. Multi-level path analysis on data from 101 leaders and 619 subordinates provided support to the moderating effect of leader extraversion, such that the relationship between transformational leadership and employee vitality is stronger when the level of leader extraversion is high. Moreover, a moderated mediation procedure showed that the indirect effect of transformational leadership on job improvement via employee vitality was conditional to the level of leader extraversion. We highlight the original contributions of these findings by discussing the moderating role of leader extraversion as an understudied theoretical alternative to its already well-explored role as an antecedent to leadership behaviors. On a practical level, our results indicate that organizations should consider not only what leaders do (transformational leadership behaviors) but also how these behaviors are contextualized by leaders’ typical approach (extraversion) to instill a maximum of positive emotion such as vitality in employees.
The present work investigates the excitation process by which free-stream disturbances are transformed into vortex-core perturbations. This problem of receptivity is modelled in terms of the resolvent in frequency space as the linear response to forcing. This formulation of receptivity suggests that non-normality of the resolvent is necessary to allow free-stream disturbances to excite the vortex core. Considering a local (in frequency) measure of non-normality, we show that vortices are frequency-selectively non-normal in a narrow frequency band of retrograde perturbations while the rest of the range is governed by an effectively normal operator, thus not contributing to receptivity. Canonical decomposition of the resolvent reveals that vortices are most susceptible to coiled filaments localised about the critical layer that induce bending waves on the core. Considering Lamb–Oseen, Batchelor and Moore–Saffman vortices as reference-flow models, we find free-stream receptivity to be essentially generic and independent of the axial wavelength on the considered range. A stochastic interpretation of the results could be a model for trailing-vortex meandering.
Light sheet fluorescence microscopy (LSFM) allows for high-resolution three-dimensional imaging with minimal photo-damage. By viewing the sample from different directions, different regions of large specimens can be imaged optimally. Moreover, owing to their good spatial resolution and high signal-to-noise ratio, LSFM data are well suited for image deconvolution. Here we present the Huygens Fusion and Deconvolution Wizard, a unique integrated solution for restoring LSFM images, and show that improvements in signal and resolution of 1.5 times and higher are feasible.
Common ragweed (2n=36), giant ragweed (2n = 24), and their reciprocal F1 hybrids (2n = 30) were analyzed for a number of traits. Hybrids of the type giant ragweed♀ × common ragweed♂ were obtained via immature embryo culture. The analyses revealed a surprising contribution of the pollen parent for features such as biomass, leaf area, and specific leaf area. Leaf morphology, however, was similar to the maternal parent. One plant, originating from crosses of the type common ragweed♀ × giant ragweed♂, developed abnormally and cytological analysis revealed the presence of 24 chromosomes in its somatic cells. Probably this plant had an androgenetic origin.
Atomic force microscopy (AFM) is used to measure local electrical conductivity of
HPHT nanodiamonds (NDs) dispersed on Au substrate in the as-received state and
after thermal or plasma treatments. Oxygen-treated NDs are highly electrically
resistive, whereas on hydrogen-treated NDs electric current around -200 pA at -2
V is detected. The as-received NDs as well as NDs after an underwater
radio-frequency (RF) plasma or laser irradiation (LI) treatments contain both
electrically conductive (two types: highly and weakly conductive) and highly
resistive particles. The higher conductivity is attributed to H-terminated (RF)
or graphitized (LI) NDs. The lower conductivity is attributed to NDs with
hydrogenated amorphous carbon shell.
The articles gathered here aim at outlining a complex view of the relationship between cities in a state of ‘crisis’ and changes to policing systems, in a period marked by rapid urbanization and industrialization. They explore the connections between the rhythms of urban change and the changes in the institutions responsible for policing the city. This introduction defines ‘urban crisis’ as a brief paroxysm and a way of describing rapid urban change that is considered problematic especially in terms of social control. It examines three sets of issues to highlight the relationships between policing powers and urban dynamics: first, how the police managed to handle unforeseen, traumatic events in emergency situations; second, how the police forces tried to legitimize their status through their understanding and control of urban dynamics; and third, how the police used the discourse of urban crisis they helped to produce, as a tool for their own ends.
To determine the postprandial lipaemia response before and after intervention with healthy diets in the Medi-RIVAGE cohort of subjects with moderate risk factors of CVD.
One hundred and thirty-five adults (fifty-two men and eighty-three women) followed either a Mediterranean-type (MED) diet or a low-fat American Heart Association-type diet in a parallel design for 3 months. At entry and after 3 months, lipids, glucose and insulin were measured in the fasting samples; TAG and apolipoprotein B48 (ApoB48; a marker of intestinally derived chylomicrons) levels were measured in the fasting and postprandial samples after a standard test meal.
The MED diet only lowered (P < 0·028) fasting TAG and both diets reduced TAG and ApoB48 levels 5 h after the test meal. The overall 5 h postprandial ApoB48 response (area under curve (AUC)/incremental AUC) was lowered after both diets but this effect was more marked after the MED-diet intervention. Whatever the TAG level at entry, normo- and hyper TAG subjects showed a reduction in the postprandial ApoB48 levels after 3-month diets. BMI at entry did not impact the effect of diets given subjects with BMI < or >25 kg/m2 showed reduced postprandial ApoB48. Men and women displayed comparable postprandial changes after dietary challenges.
A MED diet appears efficient to improve postprandial lipaemia, a recently acknowledged CVD risk, in men and women at moderate cardiovascular risk.
Perennially ice-covered lakes are well known from Antarctica and also occur in the extreme High Arctic. Climate change has many implications for these lakes, including the thinning and disappearance of their perennial ice cover. The goal of this study was to consider the effects of transition to seasonal ice cover by way of limnological observations on a series of meromictic lakes along the northern coastline of Ellesmere Island, Nunavut, Canada. Conductivity-temperature profiles during a rare period of ice-free conditions (August 2008) in these lakes suggested effects of wind-induced mixing of their surface freshwater layers and the onset of entrainment of water at the halocline. Sampling of the mixed layer of one of these meromictic lakes in May and August 2008 revealed a pronounced vertical structure in phytoplankton pigments and species composition, with dominance by cyanobacteria, green algae, chrysophytes, cryptophytes and dinoflagellates, and a conspicuous absence of diatoms. The loss of ice cover resulted in an 80-fold increase in water column irradiance and apparent mixing of the upper water column during a period of higher wind speeds. Zeaxanthin, a pigment found in cyanobacteria, was entirely restricted to the <3μm cell fraction at all depths and increased by a factor of 2–17, with the greatest increases in the upper halocline region subject to mixing. Consistent with the pigment data, picocyanobacterial populations increased by a factor of 3, with the highest concentration (1.65 × 108 cells L−1) in the upper halocline. Chlorophyll a concentrations and the relative importance of phytoplankton groups differed among the four lakes during the open-water period, implying lake-specific differences in phytoplankton community structure under ice-free conditions.
Alors que l'alimentation de l'homme a beaucoup évoluée depuis ses origines, le génome humain est resté très stable. Pourtant, de très nombreux gènes ont des polymorphismes connus. En fait, on considère maintenant que les principales pathologies humaines (maladies cardiovasculaires, diabète, obésité et cancers) résultent d'une interaction entre des facteurs de succeptibilité génétique et des facteurs de l'environement, dont l'alimentation. Dans le domaine du métabolisme des lipoprotéines et des maladies cardiovasculaires, des polymorphimes de plusieurs gènes ont été identifiés et associés aux niveaux des paramètres lipidiques ou aà des réponses variables aux régimes, comme pour les apoprotéines (apo) E, B, A-IV et C-III, le LDL récepteur, la protéine microsomiale de transport (MTP), la protéine de liason des acides gras (FABP), la protéine de transport des esters de cholésterol (CETP), la lipoprotéine lipase ou la lipase hepatique. Nous réalisons une étude d'intervention à Marseille dans le but d'étudier l'interaction
Plasma concentrations of vitamin E and carotenoids are governed by several factors, including genetic factors. Single nucleotide polymorphisms (SNP) in some genes involved in lipid metabolism have recently been associated with fasting plasma concentrations of these fat-soluble micronutrients. To further investigate the role of genetic factors that modulate the plasma concentrations of these micronutrients, we assessed whether SNP in five candidate genes (apo C-III, CETP, hepatic lipase, I-FABP and MTP) were associated with the plasma concentrations of these micronutrients. Fasting plasma vitamin E and carotenoid concentrations were measured in 129 French Caucasian subjects (forty-eight males and eighty-one females). Candidate SNP were genotyped by PCR amplification followed by restriction fragment length polymorphisms. Plasma γ-tocopherol, α-carotene and β-carotene concentrations were significantly different (P < 0·05) in subjects who carried different SNP variants in hepatic lipase. Plasma α-tocopherol concentrations were significantly different in subjects who had different SNP variants in apo C-III and cholesteryl ester transfer protein (CETP). Plasma lycopene concentrations were significantly different (P < 0·05) in women who had different SNP variants in intestinal fatty acid binding protein (I-FABP). Finally, there was no effect of SNP variants in microsomal TAG transfer protein upon the plasma concentrations of these micronutrients. Most of the observed differences remained significant after the plasma micronutrients were adjusted for plasma TAG and cholesterol. These results suggest that apo C-III, CETP and hepatic lipase play a role in determining the plasma concentrations of tocopherols while hepatic lipase and I-FABP may modulate plasma concentrations of carotenoids.
The aim of our study was to investigate the relationship between dietary fibre intake and some clinical indices, blood biochemical variables and the incidence of cardiovascular disease and cancers in France, taking advantage of an ongoing cohort, the Supplementation en Vitamines et Minéraux AntioXydants (SU.VI.MAX) intervention study. This preliminary report provides data on dietary fibre intake in this French adult population group of 4080 subjects (2168 men and 1912 women) aged 45–65 years at inclusion. The data obtained for fibre intake indicate that most men and women have low to moderate intakes of total dietary fibre (mean 21·0 and 17·1 g/d respectively), with only 21% of the men and 7% of the women having total dietary fibre intakes at the recommended level (i.e. >25 g/d) and soluble fibre accounting for 19% of the total dietary fibre intake for both genders. The main food sources of dietary fibre are cereals (30–35% total), vegetables (20–24% total) and fruit (19–22% total). No marked regional differences were observed within France. The highest dietary fibre intakes have been found to be associated with a lower BMI, blood systolic pressure, plasma triacylglycerols and plasma glucose in men and lower BMI in women. Overall, these data support the concept of a beneficial effect of a high dietary fibre intake on cardiovascular disease risk.
Radio astronomy in the decameter to centimeter wavelength range is facing new challenges because of man made interferences due to increasing needs in telecommunications. At the Radioastronomy department of Paris Meudon Observatory, we have been working since four years on high dynamic range digital receivers based on Digital Signal Processors (DSP). The first achievement is a digital spectro- polarimeter devoted to spectroscopy of astrophysical radiation in decameter range, now in operation at the Nancay Decameter array. The block diagram of the receiver includes a high dynamic range analogue section followed by a 12 bits analogue to digital converter. The digital part makes use of high power, programmable digital circuits for signal processing, arranged in a dedicated parallel architecture, able to compute in real time the power spectrum and the correlation of the input signals. This receiver was also used, as spectrometer backend, at Nancay decimetric radiotelescope and has performed very well in the presence of very strong interferences. We are presently working on a new digital receiver with broader bandwidth. The objective is 2 × 25 MHz band with at least 60 dB dynamic range. This new receiver will use additional computation power in order to recognise and avoid man made interferences which corrupt the radio astronomical signal. At the Nancay Radioastronomy Observatory, we have started to develop a new digital configurable receiver with 8 times 25 MHz band and ten thousand channels. For low frequency radioastronomy, direct spectrum computation technique is really powerful and offers new capabilities for real time interferences excision. Fig. 1 shows pulsar observations in the presence of interference made with the DSP receiver on the UTR-2 radiotelescope. Fig. 2 shows the effect of satellite interfernce on OH observations made with the Nancay telescope. Fig. 3 shows the block diagram of the DSP system and demonstrates how offline excision of interference in the frequency time-domain enables recovery of the signal. The final spectrum had 960 minutes integration on and off source and took 8045 minutes of procession on a 450 MHz Pentium II.
One must begin with f, and then tune its octave pure. After that tune c′, a fifth from f, and make it completely pure. Then lower it just enough that it still seems good and the ear can tolerate it. From c′, tune its lower octave pure. Then tune its fifth g in the same way, narrowing it to the same degree as the first. Then tune its upper octave pure, which is g′. Tune d′, and then tune this fifth in the same way, narrowing it like the others. Then pause at this point and perform the trial, which is done in this way. Tune b♭, next to c′, to the fifth f′, next to g′, and keep the b♭ a bit high, so that this fifth is tempered [temperée] and is the same as the others. Then play the d′ that you have tuned, which makes the major third against b♭ and the minor third against f′. When this chord is found to be good, everything which has been tuned is good, because the tuning is proven only by the thirds. When they are found to be good throughout, the tuning is correct.
Continue then, and follow the order used at the beginning. Go by octaves and fifths to the last note, and do not tune any fifth after the first trial mentioned above if the third within it does not prove to be good, as you may observe in the example that follows.