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The hyperpolarization of biological samples using dissolution dynamic nuclear polarization (dDNP) has become an attractive method for the monitoring of fast chemical and enzymatic reactions using NMR by taking advantage of a large signal increase. This approach is actively developing but still needs key methodological breakthroughs to be used as an analytical method for the monitoring of complex networks of simultaneous metabolic pathways. In this article, we use the deceptively simple example of glucose-6-phosphate (G6P) oxidation reaction by the enzyme G6P dehydrogenase (G6PDH) to discuss some important methodological aspects of dDNP kinetic experiments, such as its robustness and its ability to provide repeatable results as well as the capacity of this time-resolved methodology to test kinetic models and hypotheses and to provide reliable parameter estimates. To illustrate the potential of our approach, we report the first direct and quantitative evidence of selectivity of G6PDH toward the β anomer of G6P.

Purpose: We aimed to describe the ethical issues encountered by health care workers during the first COVID-19 outbreak in French intensive care units (ICUs), and the factors associated with their emergence. Methods: This descriptive multicentre survey study was conducted by distributing a questionnaire to 26 French ICUs, from 1 June to 1 October 2020. Physicians, residents, nurses, and orderlies who worked in an ICU during the first COVID-19 outbreak were included. Multiple logistic regression models were performed to identify the factors associated with ethical issues. Results: Among the 4,670 questionnaires sent out, 1,188 responses were received, giving a participation rate of 25.4%. Overall, 953 participants (80.2%) reported experiencing issue(s) while caring for patients during the first COVID-19 outbreak. The most common issues encountered concerned the restriction of family visits in the ICU (91.7%) and the risk of contamination for health care workers (72.3%). Nurses and orderlies faced this latter issue more than physicians (adjusted odds ratio [ORa], 2.98; 95% confidence interval [CI], 1.87 to 4.76; P< 0.001 and ORa, 4.35; 95% CI, 2.08 to 9.12; P< 0.001, respectively). They also faced more the issue “act contrary to the patient's advance directives” (ORa, 4.59; 95% CI, 1.74 to 12.08; P< 0.01 and ORa, 10.65; 95% CI, 3.71 to 30.60; P< 0.001, respectively). A total of 1,132 (86.9%) respondents thought that ethics training should be better integrated into the initial training of health care workers. Conclusion: Eight out of ten responding French ICU health care workers experienced ethical issues during the first COVID-19 outbreak. Identifying these issues is a first step towards anticipating and managing such issues, particularly in the context of potential future health crises.

Les politiques publiques parviennent difficilement à rendre les systèmes alimentaires plus sains et plus durables, en particulier parce que les enjeux environnementaux, agricoles, alimentaires et de santé sont souvent considérés séparément. Le concept de One Healtha justement émergé pour raisonner conjointement l’ensemble de ces enjeux et trouver des solutions qui concernent à la fois la santé et l’environnement. Il repose sur un principe simple, selon lequel la protection de la santé de l’être humain passe par celle de l’animal et de leurs interactions avec l’environnement. Pour opérationnaliser le concept, nous proposons de considérer les organismes concernés (plantes, animaux, êtres humains, microorganismes), les échelles de temps et d’espace auxquelles les flux de matières ont lieu, ainsi que les niveaux de gestion qui les sous-tendent. Nous faisons l’hypothèse que cette approche, basée sur l’analyse des relations entre la gestion des agroécosystèmes et des élevages, l’alimentation humaine et leurs effets sur le système Terre (eau, sol, biodiversité…), permettrait de définir des politiques préventives et intégrées. Des exemples portant sur l’intensification de l’agriculture, les systèmes alternatifs, les controverses sur l’élevage et les évolutions à bas bruits de variables environnementales, sont examinés selon cette approche. Nous discutons des conditions du développement d’un récit mobilisateur d’acteurs territoriaux et des politiques publiques pour la promotion d’une approche systémique One Healthdans laquelle l’alimentation est considérée comme un bien commun.

The bioactive lipid mediator sphingosine 1-phosphate (S1P) was recently assigned critical roles in platelet biology: whereas S1P1 receptor-mediated S1P gradient sensing was reported to be essential for directing proplatelet extensions from megakaryocytes (MKs) toward bone marrow sinusoids, MK sphingosine kinase 2 (Sphk2)–derived S1P was reported to further promote platelet shedding through receptor-independent intracellular actions, and platelet aggregation through S1P1. Yet clinical use of S1P pathway modulators including fingolimod has not been associated with risk of bleeding or thrombosis. We therefore revisited the role of S1P in platelet biology in mice. Surprisingly, no reduction in platelet counts was observed when the vascular S1P gradient was ablated by impairing S1P provision to plasma or S1P degradation in interstitial fluids, nor when gradient sensing was impaired by S1pr1 deletion selectively in MKs. Moreover, S1P1 expression and signaling were both undetectable in mature MKs in situ, and MK S1pr1 deletion did not affect platelet aggregation or spreading. When S1pr1 deletion was induced in hematopoietic progenitor cells, platelet counts were instead significantly elevated. Isolated global Sphk2 deficiency was associated with thrombocytopenia, but this was not replicated by MK-restricted Sphk2 deletion and was reversed by compound deletion of either Sphk1 or S1pr2, suggesting that this phenotype arises from increased S1P export and S1P2 activation secondary to redistribution of sphingosine to Sphk1. Consistent with clinical observations, we thus observe no essential role for S1P1 in facilitating platelet production or activation. Instead, S1P restricts megakaryopoiesis through S1P1, and can further suppress thrombopoiesis through S1P2 when aberrantly secreted in the hematopoietic niche.

The bioactive lipid mediator sphingosine 1-phosphate (S1P) was recently assigned critical roles in platelet biology: whereas S1P1receptor-mediated S1P gradient sensing was reported to be essential for directing proplatelet extensions from megakaryocytes (MKs) toward bone marrow sinusoids, MK sphingosine kinase 2 (Sphk2)–derived S1P was reported to further promote platelet shedding through receptor-independent intracellular actions, and platelet aggregation through S1P1. Yet clinical use of S1P pathway modulators including fingolimod has not been associated with risk of bleeding or thrombosis. We therefore revisited the role of S1P in platelet biology in mice. Surprisingly, no reduction in platelet counts was observed when the vascular S1P gradient was ablated by impairing S1P provision to plasma or S1P degradation in interstitial fluids, nor when gradient sensing was impaired by S1pr1deletion selectively in MKs. Moreover, S1P1expression and signaling were both undetectable in mature MKs in situ, and MK S1pr1deletion did not affect platelet aggregation or spreading. When S1pr1deletion was induced in hematopoietic progenitor cells, platelet counts were instead significantly elevated. Isolated global Sphk2 deficiency was associated with thrombocytopenia, but this was not replicated by MK-restricted Sphk2deletion and was reversed by compound deletion of either Sphk1or S1pr2, suggesting that this phenotype arises from increased S1P export and S1P2activation secondary to redistribution of sphingosine to Sphk1. Consistent with clinical observations, we thus observe no essential role for S1P1in facilitating platelet production or activation. Instead, S1P restricts megakaryopoiesis through S1P1, and can further suppress thrombopoiesis through S1P2when aberrantly secreted in the hematopoietic niche.

L’agriculture et l’alimentation doivent relever de nombreux défis environnementaux et sanitaires. Le développement de scénarios prospectifs est une approche pour concevoir et évaluer des stratégies y répondant. Nous comparons ici sept scénarios ayant en commun l’objectif de neutralité carbone en 2050. Ces scénarios diffèrent cependant pour l’utilisation des terres, les pratiques agricoles et les régimes alimentaires. Nous montrons qu’ils mobilisent différemment les services écosystémiques, l’économie circulaire, la sobriété et les technologies. Les enjeux de santé humaine et de biodiversité ne sont pas toujours considérés explicitement. Notre analyse permet de distinguer les scénarios basés sur des changements sociétaux, tels que la baisse de la consommation de produits animaux, de ceux misant plutôt sur des paris technologiques.

The functional heterogeneity of HDL is attributed to its diverse bioactive components. We evaluated whether the vasodilatory effects of HDL differed across HDL subpopulations, reflecting their distinct molecular composition. The capacity of five major HDL subfractions to counteract the inhibitory effects of oxidized LDL on acetylcholine-induced vasodilation was tested in a rabbit aortic rings model. NO production, an essential pathway in endothelium-dependent vasorelaxation, was studied in simian vacuolating virus 40-transformed murine endothelial cells (SVECs). Small dense HDL3 subfractions displayed potent vasorelaxing activity (up to +31% vs. baseline, P< 0.05); in contrast, large light HDL2 did not induce aortic-ring relaxation when compared on a total protein basis. HDL3 particles were enriched with sphingosine-1-phosphate (S1P) (up to 3-fold vs. HDL2), with the highest content in HDL3b and -3c that concomitantly revealed the strongest vasorelaxing properties. NO generation was enhanced by HDL3c in SVECs (1.5-fold, P< 0.01), a phenomenon that was blocked by the S1P receptor antagonist, VPC 23019. S1P-enriched reconstituted HDL (rHDL) was a 1.8-fold (P< 0.01) more potent vasorelaxant than control rHDL in aortic rings. Small dense HDL3 particles displayed potent protective effects against oxidative stress-associated endothelium dysfunction, potentially reflecting their elevated content of S1P that might facilitate interaction with S1P receptors and ensuing NO generation.

Face aux nombreux défis sociétaux à relever (environnement, sécurité alimentaire, santé), différentes formes d’agriculture sont envisagées. Agriculture biologique, agriculture de conservation des sols et maintenant agriculture régénératrice sont trois récits fondateurs se référant à l’agroécologie. Toutefois, l’agriculture régénératrice, nouvelle arrivée en France, reste ambiguë. Nous proposons un cadre d’analyse des formes d’agriculture en termes d’impacts et de services, que nous mobilisons pour comparer l’agriculture régénératrice à celles auxquelles elle se réfère et qui sont bien documentées dans la littérature scientifique. Cette analyse permet d’éclairer des points critiques de l’agriculture régénératrice tels que la question des pesticides et du niveau de séquestration du carbone dans les sols. Ensuite, nous identifions les atouts, faiblesses, opportunités et menaces pour le changement d’échelle de cette agriculture. Nous montrons qu’un atout majeur de l’agriculture régénératrice est de reposer sur un récit mettant en avant un principe, la « régénération » des biens communs (sols, eau, air, biodiversité), qui peut entraîner l’adhésion d’une diversité d’acteurs. Cependant, la mobilisation des acquis de l’agroécologie, en tant que science, pratique et mouvement, pourrait aider à préciser son contenu, encore flou, de façon à ce que ses promesses se traduisent en de réels progrès et ne soient pas exclusivement centrés sur le carbone.

An isolated mitochondrial complex III (CIII) defect constitutes a rare cause of mitochondrial disorder. Here we present the second case involving UQCRC2gene, which encodes core protein 2, one of the 11 structural subunits of CIII. The patient has the same mutation (c.547C>T; p.Arg183Trp) as the first case and presented with neonatal lactic acidosis, hypoglycemia and severe episodes of liver failure. Our study expands the few reported cases of CIII deficiency of nuclear origin.

Designing or improving farming systems requires understanding their dynamics so as to predict their behaviour in response to management. Simulation tools can potentially support the process by which farmers and scientists might obtain such an encompassing understanding. The usability of these tools is, however, partially inhibited by the inherent complexity of the interactions at work in farm-scale models. Whereas such models are generally used in isolation, here we present an approach in which a field-scale diagnosis method complements a farm-scale simulation model. This diagnosis method lends itself easily to an intelligible presentation of field-specific knowledge that can be fed to the simulation tool for more encompassing considerations. Our approach is used to support the design of novel management strategies in grassland-based beef systems and proved to be effective when applied to two farms in the French Pyrenees. Thanks to the integrative representation of the various processes, including the management ones, simulation contributed to deeper learning of both scientists and farmers about room for manoeuvre for increasing self-sufficiency for forage. The diagnosis phase enhanced the learning process by providing a simpler framework in which elementary problems at field scale could be considered separately before being examined concurrently at farm scale in the simulation phase.

Metabolic syndrome is very common and is associated with significantly increased risk for both cardiovascular disease and type 2 diabetes. At present, no unifying mechanism can explain it. However, insulin resistance is a key feature of this syndrome, plays a key role in triglyceride metabolism and contributes to dyslipidemia and development of type 2 diabetes. Here, we review the mechanisms involved in the overproduction of large VLDL and their catabolism and finally potential therapeutic targets to provide a more complete approach to treatment of these lipid abnormalities.

During pregnancy, the placenta ensures multiple functions, which are directly involved in the initiation, outcome of gestation and fetal growth. Human implantation involves a major invasion of the uterus wall and a complete remodeling of the uterine arteries by the extravillous cytotrophoblasts (EVCT) during the first trimester of pregnancy. Abnormality of these early steps of placental development leads to poor placentation, fetal growth defects and is very often associated with preeclampsia, a major and frequent complication of human pregnancy. Unexpectedly, genetic studies performed in mice established that the peroxisome proliferator-activated receptor-γ (PPARγ) is essential for placental development. In the human placenta, PPARγ is specifically expressed in the villous cytotrophoblast (VCT) and the syncytiotrophoblast (ST) as well as in the EVCT along their invasive pathway. To study the mechanisms that control human trophoblast invasion during early placental development and to provide new insight in the understanding of preeclampsia, we have developed in vitro models of human invasive trophoblasts. We observed that activation of the ligand-activated nuclear receptor PPARγ agonists inhibits the trophoblastic invasion process in a concentration-dependent manner. Analysis of PPARγ-target genes revealed that placental growth hormone, the protease PAPP-A and the human chorionic gonadotropin hormone (hCG) might be involved in the PPARγ-mediated effect in an autocrine manner. The presence of oxidized- LDLs at the maternofetal interface suggests that oxidized-LDLs from maternal sera might be a source of potential PPARγ ligands for the trophoblasts. Indeed, oxidized-LDLs decrease trophoblast invasion in vitro and analysis of their content revealed that they contain potent PPARγ agonists such as eicosanoids, but also oxysterols, which are ligands for another nuclear receptor, the liver X Receptor (LXR). LXRß was found to be expressed in trophoblast and LXR agonists shown to inhibit trophoblast invasion. Together, these data underscore a major role for PPARγ in the control of human trophoblast invasion during early placental development and suggest that ligands such as oxidized-LDLs at the implantation site might contribute to the modulation of trophoblast invasion through activation of PPARγ and LXRß, two nuclear receptors that modulate the human trophoblastic cell invasion process.

During pregnancy, the placenta ensures multiple functions, which are directly involved in the initiation, outcome of gestation and fetal growth. Human implantation involves a major invasion of the uterus wall and a complete remodeling of the uterine arteries by the extravillous cytotrophoblasts (EVCT) during the first trimester of pregnancy. Abnormality of these early steps of placental development leads to poor placentation, fetal growth defects and is very often associated with preeclampsia, a major and frequent complication of human pregnancy. Unexpectedly, genetic studies performed in mice established that the peroxisome proliferator-activated receptor- (PPAR) is essential for placental development. In the human placenta, PPAR is specifically expressed in the villous cytotrophoblast (VCT) and the syncytiotrophoblast (ST) as well as in the EVCT along their invasive pathway. To study the mechanisms that control human trophoblast invasion during early placental development and to provide new insight in the understanding of preeclampsia, we have developed in vitro models of human invasive trophoblasts. We observed that activation of the ligand-activated nuclear receptor PPAR agonists inhibits the trophoblastic invasion process in a concentration-dependent manner. Analysis of PPAR-target genes revealed that placental growth hormone, the protease PAPP-A and the human chorionic gonadotropin hormone (hCG) might be involved in the PPAR-mediated effect in an autocrine manner. The presence of oxidized- LDLs at the maternofetal interface suggests that oxidized-LDLs from maternal sera might be a source of potential PPAR ligands for the trophoblasts. Indeed, oxidized-LDLs decrease trophoblast invasion in vitro and analysis of their content revealed that they contain potent PPAR agonists such as eicosanoids, but also oxysterols, which are ligands for another nuclear receptor, the liver X Receptor (LXR). LXRß was found to be expressed in trophoblast and LXR agonists shown to inhibit trophoblast invasion. Together, these data underscore a major role for PPAR in the control of human trophoblast invasion during early placental development and suggest that ligands such as oxidized-LDLs at the implantation site might contribute to the modulation of trophoblast invasion through activation of PPAR and LXRß, two nuclear receptors that modulate the human trophoblastic cell invasion process.

The mechanism by which hypoxia induces gene transcription involves the inhibition of HIF-1α (hypoxia-inducible factor-1 α subunit) PHD (prolyl hydroxylase) activity, which prevents the VHL (von Hippel-Lindau)-dependent targeting of HIF-1α to the ubiquitin/proteasome pathway. HIF-1α thus accumulates and promotes gene transcription. In the present study, first we provide direct biochemical evidence for the presence of a conserved hypoxic signalling pathway in Drosophila melanogaster. An assay for 2-oxoglutarate-dependent dioxygenases was developed using Drosophila embryonic and larval homogenates as a source of enzyme. Drosophila PHD has a low substrate specificity and hydroxylates key proline residues in the ODD (oxygen-dependent degradation) domains of human HIF-1α and Similar, the Drosophila homologue of HIF-1α. The enzyme promotes human and Drosophila [35S]VHL binding to GST (glutathione S-transferase)–ODD-domain fusion protein. Hydroxylation is enhanced by proteasomal inhibitors and was ascertained using an anti-hydroxyproline antibody. Secondly, by using transgenic flies expressing a fusion protein that combined an ODD domain and the green fluorescent protein (ODD–GFP), we analysed the hypoxic cascade in different embryonic and larval tissues. Hypoxic accumulation of the reporter protein was observed in the whole tracheal tree, but not in the ectoderm. Hypoxic stabilization of ODD–GFP in the ectoderm was restored by inducing VHL expression in these cells. These results show that Drosophila tissues exhibit different sensitivities to hypoxia.

Objective:To verify whether polyunsaturated fatty acids (PUFAs) can regulate the expression of the nuclear receptor peroxisome proliferator‐activated receptor γ (PPARγ) in human adipose tissue. Research Methods and Procedures:The effect of various PUFAS on PPARγ1 and ‐γ2 mRNA expression was investigated in freshly isolated adipocytes prepared from fat samples obtained during surgery. PPARγ mRNA levels were also determined in subcutaneous adipose tissue biopsies of 11 obese women, in the fasting state, to search for in vivo associations between PPARγ expression and plasma PUFA concentrations. PPARγ mRNA levels were determined by reverse‐transcription competitive polymerase chain reaction. Results:Eicosapentaenoic acid (EPA) significantly increased PPARγ1 mRNA levels in isolated adipocytes, without affecting the expression of PPARγ2. The other tested fatty acids (linolenic acid, docosahexaenoic acid and ω‐6 PUFAs) had no effect. The effect of EPA was dependent on the concentration (maximal effect after 6 hours with 50 μM) and was not reproduced by activators of the different members of the PPAR family. In addition, a strong positive correlation was found between plasma EPA concentrations and PPARγ mRNA levels in adipose tissue of obese subjects. Discussion:Our results demonstrate that adipose tissue PPARγ1 mRNA concentration is positively regulated by EPA, suggesting that the composition of dietary lipids may affect PPARγ gene expression in vivo in humans. These data also suggest that an induction of the expression of this nuclear receptor isoform might be involved in the mechanism of action of EPA and in some of its beneficial effects.

Alpha-tocopherol (-T) is the most effective lipid-soluble antioxidant present in cells. We investigated the efficacy of -T supplements for preventing lipid peroxidation in patients with Alagille syndrome, according to the severity of cholestasis. Patients were assigned to two groups on the basis of plasma bilirubin concentration (group I, bilirubin <100 M; group II, bilirubin >100 M). -T concentrations were determined in plasma, in isolated lipoproteins, and in red blood cell membranes. In both groups of patients, -T concentrations in plasma were similar to those in control subjects, but the distribution of -T in lipoproteins was affected by the abnormal lipoprotein pattern in these patients. The efficacy of -T was estimated by determining the amount of hydroperoxide produced from phosphatidylcholine and phosphatidylethanolamine (PE) molecular species owing to oxidative stress induced by lipoxygenase treatment. The concentrations of phosphatidylcholine molecular species and its corresponding hydroperoxides were significantly higher in both groups of patients. In group I, -T and PE molecular species concentrations were similar to those in control subjects, but PE hydroperoxide concentrations were higher than those in the control subjects. In group II, -T concentration was significantly lower and the concentrations of some PE molecular species and all PE hydroperoxides were lower than those in the control subjects. In conclusion, erythrocyte membrane -T concentration was significantly lower only in patients with severe jaundice, despite -T supplementation, raising the question as to whether the usual treatment was appropriate in this group.

Alpha-tocopherol (a-T) is the most effective lipid-soluble antioxidant present in cells. We investigated the efficacy of a-T supplements for preventing lipid peroxidation in patients with Alagille syndrome, according to the severity of cholestasis. Patients were assigned to two groups on the basis of plasma bilirubin concentration (group I, bilirubin <100 µM; group II, bilirubin >100 µM). a-T concentrations were determined in plasma, in isolated lipoproteins, and in red blood cell membranes. In both groups of patients, a-T concentrations in plasma were similar to those in control subjects, but the distribution of a-T in lipoproteins was affected by the abnormal lipoprotein pattern in these patients. The efficacy of a-T was estimated by determining the amount of hydroperoxide produced from phosphatidylcholine and phosphatidylethanolamine (PE) molecular species owing to oxidative stress induced by lipoxygenase treatment. The concentrations of phosphatidylcholine molecular species and its corresponding hydroperoxides were significantly higher in both groups of patients. In group I, a-T and PE molecular species concentrations were similar to those in control subjects, but PE hydroperoxide concentrations were higher than those in the control subjects. In group II, a-T concentration was significantly lower and the concentrations of some PE molecular species and all PE hydroperoxides were lower than those in the control subjects. In conclusion, erythrocyte membrane a-T concentration was significantly lower only in patients with severe jaundice, despite a-T supplementation, raising the question as to whether the usual treatment was appropriate in this group.

Abstract: Plasma selenium (Se) concentration and erythrocyte glutathione peroxidase activity (GPx) were assessed in a population of healthy preschool children two to five years old, residing in the city of Paris. In the 118 subjects, mean (±SD) plasma Se concentration was 62.10 ±13.96 μg/L, and mean GPx activity was 23.58±8.52 U/g Hb. Mean plasma Se of male children was significantly (p=0.001) higher (12%) than levels of girls. Plasma selenium levels were not correlated with erythrocyte GPx activity. Children from Mediterranean origin had a slightly lower erythrocyte GPx activity (p<0.05) than children from other regions. Mean plasma Se concentration of this group corresponded to the lower limit of intervals, which characterizes geographical regions of intermediate selenium concentrations.

This paper gives an approach on Unified Power Flow Controller (UPFC) impacts on the relays in a Power System. The results are based on relay tests fed by voltages and currents calculated with a complete simulation with EMTP (Electromagnetic Transients Program) code. The series part of the UPFC modifies the line impedance and could disturb the relays measurements. The UPFC design, especially the philosophies of protection for the series transformer, have an impact on line impedance. The type of relays and the configuration of grid have to be taken into account.

In its first part, this paper deals with steady state operation of a synchronous generator knowing its geometry, its magnetic characteristic, its output voltage and the field current. The second part is about the computation of the field current and load angle knowing the load of the synchronous generator, in terms of active power (P), reactive power (Q) and terminal voltage (V).While the magnetic material characteristic is linear, the machine's equations can be solved analytically for the determination of its operating point. But when it is in a nonlinear area the problem becomes more intricate. In that case numerical modeling is very useful. In this paper we propose a model based on the simultaneous solution of electric and magnetic equations, where the latter are solved using the FEM. To consider the movement, the electric equations are expressed in d-q reference axes. As current and load angle are unknown, one has to add a new nonlinear electric equation to the classical nonlinear magnetic system. In our model the solution is obtained using the Newton-Raphson iterative procedure.Numerical applications have been done on an EDF (Electricité de France) 1300MW synchronous generator designed by GEC.ALSTHOM. To show the validity of the model different trials have been performed, first without load, then when the machine produces active and reactive power.

To examine the influence of the oro-sensory properties of different beverages on spontaneous intake of drinks, and the consequence of the volume of fluid ingested on subsequent food intake, 24 subjects (12 men, 12 women), slightly dehydrated, had accessad libitum, during four different experimental sessions in a cross-over design, to one of four commercial beverages without any other drink. The four beverages differed in flavour and caloric content: mineral water; the same mineral water flavoured with orange and unsweetened; the same mineral water flavoured with orange and sweetened with 100 g/l sucrose; or equally sweetened with 50 mg/l aspartame.Ad libitum: lunch was served 15 min after the subjects had access to the beverages and dinner was served when they spontaneously requested it, about 6 h after the end of lunch. The nature of the beverage exerted a small but significant effect on the cumulative fluid intake of the subjects. They consumed slightly more of the two sweetened beverages than the mineral water, and slightly less of the orange-flavoured beverage. However, energy intake and macronutrient selection during lunch and dinner on the experimental days and on the following day did not differ significantly between the different conditions. This resulted in a significantly higher total energy intake when the imposed beverage contained sucrose. Moreover, in such experimental conditions, with only one type of beverage to drink, the flavour of this beverage had little influence on the amount of fluid consumed, and the volume consumed did not influence subsequent food intake. As a consequence, the energy provided by the sucrose-sweetened beverage was not taken in account in the overall energy balance by the subjects, at least in the short term.

This paper defines a frequency characteristic matrix (Gdq(jw)= (gij(jw))2*2) for AC power systems in the direct and quadrature co-ordinate system. It demonstrates the Y-symmetry of the matrix Gdq(jw), i.e., g11(jw) = g22(jw)and g12(jw) =-g21(jw) and the complete decomposability of the system. Based upon these important properties, a Double-input and Double-Output system may be reduced to two uncoupled Single-Input and Single-Output systems, which makes it possible to simplify the identification and stability analysis in frequency domain for interconnected power systems. Furthermore, it discusses the physical interpretation for the elements gij(jw)(i, j = 1, 2) in permanent regime.

The risk of atherosclerosis is intimately related to the heterogeneity of low‐density lipoprotein (LDL) particles. The potential relationship between oxidative modification of distinct LDL subspecies and induction of apoptosis in arterial wall cells is indeterminate. The capacity of light LDL3 versus dense LDL5 to induce cytotoxicity in endothelial cells as a function of the degree of copper‐mediated oxidation was compared. Mildly oxidized LDL3 (oxLDL3) exerted potent cytotoxicity, which was intimately related to both the degree of oxidation and the oxLDL3 concentration based on either cholesterol content or particle number. In contrast, dense LDL5 particles exerted a minor effect on cell viability. Cells incubated with oxLDL3 exhibited apoptotic features, with cytoplasmic condensation, cell or nuclear fragmentation, and accumulation of DNA fragments. OxLDL3‐induced apoptosis involved cytoplasmic release of cytochrome c, with a concomitant increase in caspase‐3‐like protease activity. OxLDL3 particles were uniquely distinct from oxLDL5 particles in their elevated content of lipid hydroperoxides. Hydroperoxide removal by NaBH4markedly reduced oxLDL3‐induced cytotoxicity, leading to an increase in cell viability. Lipid hydroperoxide content of oxidatively modified LDL subclasses is therefore a major determinant of the induction of apoptosis in endothelial cells. These data are highly relevant to atherogenic hypercholesterolemia, in which the LDL phenotype is dominated by elevated concentrations of light LDL3.

The electrical resistivity ϱ of UAs1−xSexsolid solutions has been measured between 13 K and room temperature. The magnetic phase diagram has been deduced. Effects of uniaxial stress on ϱ allow to understand some results and to reveal anisotropy of ϱ.

Resistivity and Hall effect measurements on the PuSb1−xTexsystem are presented. They give evidence for a semi-metallic character for PuSb, with a very low carrier concentration. The transport properties of PuTe can be understood assuming a very small gap (≈20 meV) in its band structure.

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