66 resultados para Mixed-integer quadratically-constrained programming
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1. The relation between dietary carbohydrate: lipid ratio and the fuel mixture oxidized during 24 h was investigated in eleven healthy volunteers (six females, and five males) in a respiration chamber. Values of the fuel mixture oxidized were estimated by continuous indirect calorimetry and urinary nitrogen measurements. 2. The subjects, were first given a mixed diet for 7 d and spent the last 24 h of the 7 d period in a respiration chamber for continuous gas-exchange measurement. The fuels oxidized during 2.5 h or moderate exercise were also measured in the respiration chamber. After an interval of 2 weeks from the end of the mixed-diet period, the same subjects were given an isoenergetic high-carbohydrate low-fat diet for 7 d, and the same experimental regimen was repeated. 3. Dietary composition markedly influenced the fuel mixture oxidized during 24 h and this effect was still present 12 h after the last meal in the postabsorptive state. However, the diets had no influence on the substrates oxidized above resting levels during exercise. With both diets, the 24 h energy balance was slightly negative and the energy deficit was covered by lipid oxidation. 4. With the high-carbohydrate low-fat diet, the energy expenditure during sleep was found to be higher than that with the mixed diet. 5. It is concluded that: (a) the composition of the diet did not influence the fuel mixture utilized for moderate exercise, (b) the energy deficit calculated for a 24 h period was compensated by lipid oxidation irrespective of the carbohydrate content of the diet, (c) energy expenditure during sleep was found to be higher with the high-carbohydrate low-fat diet than with the mixed diet.
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Background and Aims The frequency at which males can be maintained with hermaphrodites in androdioecious populations is predicted to depend on the selfing rate, because self-fertilization by hermaphrodites reduces prospective siring opportunities for males. In particular, high selfing rates by hermaphrodites are expected to exclude males from a population. Here, the first estimates are provided of the mating system from two wild hexaploid populations of the androdioecious European wind-pollinated plant M. annua with contrasting male frequencies.Methods Four diploid microsatellite loci were used to genotype 19-20 progeny arrays from two populations of M. annua, one with males and one without. Mating-system parameters were estimated using the program MLTR.Key Results Both populations had similar, intermediate outcrossing rates (t(m) = 0.64 and 0.52 for the population with and without males, respectively). The population without males showed a lower level of correlated paternity and biparental inbreeding and higher allelic richness and gene diversity than the population with males.Conclusions The results demonstrate the utility of new diploid microsatellite loci for mating system analysis in a hexaploid plant. It would appear that androdioecious M. annua has a mixed-mating system in the wild, an uncommon finding for wind-pollinated species. This study sets a foundation for future research to assess the relative importance of the sexual system, plant-density variation and stochastic processes for the regulation of male frequencies in M. annua over space and time.
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Abstract in English : Ubiquitous Computing is the emerging trend in computing systems. Based on this observation this thesis proposes an analysis of the hardware and environmental constraints that rule pervasive platforms. These constraints have a strong impact on the programming of such platforms. Therefore solutions are proposed to facilitate this programming both at the platform and node levels. The first contribution presented in this document proposes a combination of agentoriented programming with the principles of bio-inspiration (Phylogenesys, Ontogenesys and Epigenesys) to program pervasive platforms such as the PERvasive computing framework for modeling comPLEX virtually Unbounded Systems platform. The second contribution proposes a method to program efficiently parallelizable applications on each computing node of this platform. Résumé en Français : Basée sur le constat que les calculs ubiquitaires vont devenir le paradigme de programmation dans les années à venir, cette thèse propose une analyse des contraintes matérielles et environnementale auxquelles sont soumises les plateformes pervasives. Ces contraintes ayant un impact fort sur la programmation des plateformes. Des solutions sont donc proposées pour faciliter cette programmation tant au niveau de l'ensemble des noeuds qu'au niveau de chacun des noeuds de la plateforme. La première contribution présentée dans ce document propose d'utiliser une alliance de programmation orientée agent avec les grands principes de la bio-inspiration (Phylogénèse, Ontogénèse et Épigénèse). Ceci pour répondres aux contraintes de programmation de plateformes pervasives comme la plateforme PERvasive computing framework for modeling comPLEX virtually Unbounded Systems . La seconde contribution propose quant à elle une méthode permettant de programmer efficacement des applications parallélisable sur chaque noeud de calcul de la plateforme
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Rapport de synthèseDes événements pathologiques survenant pendant la période foetale prédisposent la descendance aux maladies cardiovasculaires systémiques. Il existe peu de connaissances au sujet de la circulation pulmonaire et encore moins quant aux mécanismes sous-jacents. La sous-alimentation maternelle pendant la grossesse peut représenter un modèle d'investigation de ces mécanismes, parce que chez l'animal et l'homme elle est associée à une dysfonction vasculaire systémique chez la progéniture. Chez le rat, la diète restrictive pendant la grossesse induit une augmentation du stress oxydatif dans le placenta. Les dérivés de l'oxygène sont connus pour induire des altérations épigénétiques et peuvent traverser la barrière placentaire. Nous avons dès lors spéculé que chez la souris la diète restrictive pendant la grossesse induit une dysfonction vasculaire pulmonaire chez sa progéniture qui serait liée à un mécanisme épigénétique.Pour tester cette hypothèse, nous avons examiné la fonction vasculaire pulmonaire et la méthylation de l'ADN pulmonaire à la fin de 2 semaines d'exposition à l'hypoxie chez la progéniture de souris soumises à une diète restrictive pendant la grossesse et des souris contrôles. Nous avons trouvé que la vasodilatation endothélium-dépendante de l'artère pulmonaire in vitro était défectueuse, et que l'hypertension pulmonaire et l'hypertrophie ventriculaire droite induites par l'hypoxie in vivo étaient exagérées chez la progéniture de souris soumises à une diète restrictive pendant la grossesse. Cette dysfonction vasculaire pulmonaire était associée avec une altération de la méthylation de l'ADN pulmonaire. L'administration d'inhibiteurs de la déacétylase des histones, le Butyrate et la Trichostatine-A à la progéniture de souris soumises à une diète restrictive pendant la grossesse a normalisé la méthylation de l'ADN et la fonction vasculaire pulmonaire. Finalement, l'administration du nitroxyde Tempol aux mères durant la diète restrictive pendant la grossesse a prévenu la dysfonction vasculaire et la dysméthylation chez la progéniture.Ces découvertes démontrent que chez la souris la sous-alimentation pendant la gestation induit une dysfonction vasculaire chez la progéniture qui est causée par un mécanisme épigénétique. Il est possible qu'un mécanisme similaire soit impliqué dans la programmation foetale de la dysfonction vasculaire chez les humains.
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This paper advocates the adoption of a mixed-methods research design to describe and analyze ego-centered social networks in transnational family research. Drawing on the experience of the Social Networks Influences on Family Formation project (2004-2005), I show how the combined use of network generators and semistructured interviews (N = 116) produces unique data on family configurations and their impact on life course choices. A mixed-methods network approach presents specific advantages for research on children in transnational families. On the one hand, quantitative analyses are crucial for reconstructing and measuring the potential and actual relational support available to children in a context where kin interactions may be hindered by temporary and prolonged periods of separation. On the other hand, qualitative analyses can address strategies and practices employed by families to maintain relationships across international borders and geographic distance, as well as the implications of those strategies for children's well-being.
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PURPOSE: To describe the clinical presentation of cutaneous benign mixed tumor of the eyelid and its management options. METHODS: Periocular cases of cutaneous benign mixed tumor were gathered from members of an oculoplastics specialty Internet discussion group. A total of 9 patients are described in this retrospective, interventional case series. The clinical presentation, histopathology, and management of these lesions is reviewed. RESULTS: Patients were typically asymptomatic, presenting with a slowly enlarging, nontender nodule of 2 to 8 years' duration. The lesions ranged from 4 mm to 17 mm in greatest dimension. Four of the lesions were on the eyelid margin, three in the sub-brow area of the upper eyelid, and two in the central lids. All six cases not involving the brow were fixed to the tarsus; one brow lesion was believed to be adherent to the skin. None of the lesions was associated with significant changes of the overlying epidermis, although one lesion showed overlying pigmentation. All patients underwent excisional biopsy for diagnostic or cosmetic reasons. On histopathologic examination, the tumors were biphasic, with an epithelial component exhibiting apocrine or hair follicle differentiation and a myxoid, adipocytic, chondroid, and/or fibrous stroma. The pathologic diagnoses were all consistent with cutaneous benign mixed tumor (chondroid syringoma, pleomorphic adenoma). Follow-up ranged from 2 weeks to 12 months, although several patients failed to keep scheduled follow-up appointments. No clinical recurrences were identified. CONCLUSIONS: Cutaneous benign mixed tumor may occur in the eyelid, and, although uncommon, should be included in the differential diagnosis of firm, nodular eyelid tumors. The histopathologic features are similar to those seen in this tumor type arising in other areas of the body. Preoperative consideration of this diagnostic possibility may allow the surgeon to plan for complete excision, thereby reducing the possibility of recurrence or malignant transformation.
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Splenic marginal zone (MZ) B cells are a lineage distinct from follicular and peritoneal B1 B cells. They are located next to the marginal sinus where blood is released. Here they pick up antigens and shuttle the load onto follicular dendritic cells inside the follicle. On activation, MZ B cells rapidly differentiate into plasmablasts secreting antibodies, thereby mediating humoral immune responses against blood-borne type 2 T-independent antigens. As Krüppel-like factors are implicated in cell differentiation/function in various tissues, we studied the function of basic Krüppel-like factor (BKLF/KLF3) in B cells. Whereas B-cell development in the bone marrow of KLF3-transgenic mice was unaffected, MZ B-cell numbers in spleen were increased considerably. As revealed in chimeric mice, this occurred cell autonomously, increasing both MZ and peritoneal B1 B-cell subsets. Comparing KLF3-transgenic and nontransgenic follicular B cells by RNA-microarray revealed that KLF3 regulates a subset of genes that was similarly up-regulated/down-regulated on normal MZ B-cell differentiation. Indeed, KLF3 expression overcame the lack of MZ B cells caused by different genetic alterations, such as CD19-deficiency or blockade of B-cell activating factor-receptor signaling, indicating that KLF3 may complement alternative nuclear factor-κB signaling. Thus, KLF3 is a driving force toward MZ B-cell maturation.
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Background: The relative contributions of fat and protein to the incretin effect are still largely unknown.Objective: This study assessed the incretin effects elicited by a mixed meal, and by its fat and protein components alone, with the use of a hyperglycemic clamp combined with oral nutrients.Design: Eight healthy volunteers were studied over 6 h after ingestion of a sandwich containing 1) dried meat, butter, and white bread; 2) dried meat alone; 3) butter alone; or 4) no meal (fasting control). Meals were ingested during a hyperglycemic clamp, and the incretin effect was calculated as the increment in plasma insulin after food intake relative to the concentrations observed during the control study.Results: A significant augmentation of postprandial insulin secretion, independent of plasma glycemia, occurred after ingestion of the mixed nutrients and the lipid component of the mixed meal (203 +/- 20.7% and 167.4 +/- 22.9% of control, respectively; both P < 0.05), whereas the protein component did not induce a significant incretin effect (129.0 +/- 7.9% of control; P = 0.6)Conclusions: Fat ingestion, in an amount typical of a standard meal, increases insulin secretion during physiologic hyperglycemia and thus contributes to the incretin effect. In contrast, ingestion of protein typical of normal meals does not contribute to the augmentation of postprandial insulin secretion. This trial was registered at clinicaltrials.gov as NCT00869453.
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PURPOSE: We hypothesize that untrained subjects can benefit from a greater cardiovascular stimulation than trained athletes, resembling classical aerobic-type activity, in addition to eliciting strength gains.METHODS: 3 groups of male subjects, inactive (SED), endurance trained (END) and strength trained (STR) underwent fitness (VO2max) and lower-body strength tests (isokinetic). Subjects were submitted to a session of oscillating VT, composed of 3 exercises (isometric half-squat, dynamic squat, dynamic squat with added load), each of 3 minutes duration, and repeated at 3 vibration frequencies (20, 26 and 32 Hz). VO2, heart rate and Borg scale were monitored.RESULTS: 27 healthy subjects (10 SED, 9 END and 8 STR), mean age 24.5 (SED), 25.0 (STR) and 29.8 (END) were included. VO2max was significantly different as expected (47.9 vs. 52.9 vs. 63.9 mL?min-1?kg-1, resp. for SED, STR and END). Isokinetic dominant leg extensors strength was higher in STR (3.32 N?m?kg-1 vs. 2.60 and 2.74 in SED and END). During VT, peak oxygen consumption (% of VO2max) attained was 59.3 in SED, 50.8 in STR and 48.0 in END (P<0.001 between SED and other subjects). Peak heart rate (% of heart rate max) was 82.7 in SED, 80.4 in STR and 72.4 in END. In SED, dynamic exercises without extra load elicited 51.0 % of VO2max and 72.1 % of heart rate max, and perceived effort reached 15.1/20.CONCLUSIONS: VT is an unconventional type of exercise, known to enhance strength, bone density, balance and flexibility. Users are attracted by the relative passivity. In SED, VT elicits sufficient cardiovascular response to benefit overall fitness in addition to the strength effects. VT's higher acceptance as an exercise in sedentary people, compared to jogging or cycling, can lead to better adherence to physical activity. Although long-term effects of VT on health are not available, we believe this type of mixed aerobic and resistance-type exercise can be beneficial on multiple health parameters, especially cardiovascular health.
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OBJECTIVE: To develop and validate a simple, integer-based score to predict functional outcome in acute ischemic stroke (AIS) using variables readily available after emergency room admission. METHODS: Logistic regression was performed in the derivation cohort of previously independent patients with AIS (Acute Stroke Registry and Analysis of Lausanne [ASTRAL]) to identify predictors of unfavorable outcome (3-month modified Rankin Scale score >2). An integer-based point-scoring system for each covariate of the fitted multivariate model was generated by their β-coefficients; the overall score was calculated as the sum of the weighted scores. The model was validated internally using a 2-fold cross-validation technique and externally in 2 independent cohorts (Athens and Vienna Stroke Registries). RESULTS: Age (A), severity of stroke (S) measured by admission NIH Stroke Scale score, stroke onset to admission time (T), range of visual fields (R), acute glucose (A), and level of consciousness (L) were identified as independent predictors of unfavorable outcome in 1,645 patients in ASTRAL. Their β-coefficients were multiplied by 4 and rounded to the closest integer to generate the score. The area under the receiver operating characteristic curve (AUC) of the score in the ASTRAL cohort was 0.850. The score was well calibrated in the derivation (p = 0.43) and validation cohorts (0.22 [Athens, n = 1,659] and 0.49 [Vienna, n = 653]). AUCs were 0.937 (Athens), 0.771 (Vienna), and 0.902 (when pooled). An ASTRAL score of 31 indicates a 50% likelihood of unfavorable outcome. CONCLUSIONS: The ASTRAL score is a simple integer-based score to predict functional outcome using 6 readily available items at hospital admission. It performed well in double external validation and may be a useful tool for clinical practice and stroke research.
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After 13 days of weight maintenance diet (13,720 +/- 620 kJ/day, 40% fat, 15% protein, and 45% carbohydrate), five young men (71.3 +/- 7.1 kg, 181 +/- 8 cm; means +/- SD) were overfed for 9 days at 1.6 times their maintenance requirements (i.e., +8,010 kJ/day). Twenty-four-hour energy expenditure (24-h EE) and basal metabolic rate (BMR) were measured on three occasions, once after 10 days on the weight-maintenance diet and after 2 and 9 days of overfeeding. Physical activity was monitored throughout the study, body composition was measured by underwater weighing, and nitrogen balance was assessed for 3 days during the two experimental periods. Overfeeding caused an increase in body weight averaging 3.2 kg of which 56% was fat as measured by underwater weighing. After 9 days of overfeeding, BMR increased by 622 kJ/day, which could explain one-third of the increase in 24-h EE (2,038 kJ/day); the remainder was due to the thermic effect of food (which increased in proportion with excess energy intake) and the increased cost of physical activity, related to body weight gain. This study shows that approximately one-quarter of the excess energy intake was dissipated through an increase in EE, with 75% being stored in the body. Under our experimental conditions of mixed overfeeding in which body composition measurements were combined with those of energy balance, it was possible to account for all of the energy ingested in excess of maintenance requirements.
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Through this article, we propose a mixed management of patients' medical records, so as to share responsibilities between the patient and the Medical Practitioner by making Patients responsible for the validation of their administrative information, and MPs responsible for the validation of their Patients' medical information. Our proposal can be considered a solution to the main problem faced by patients, health practitioners and the authorities, namely the gathering and updating of administrative and medical data belonging to the patient in order to accurately reconstitute a patient's medical history. This method is based on two processes. The aim of the first process is to provide a patient's administrative data, in order to know where and when the patient received care (name of the health structure or health practitioner, type of care: out patient or inpatient). The aim of the second process is to provide a patient's medical information and to validate it under the accountability of the Medical Practitioner with the help of the patient if needed. During these two processes, the patient's privacy will be ensured through cryptographic hash functions like the Secure Hash Algorithm, which allows pseudonymisation of a patient's identity. The proposed Medical Record Search Engines will be able to retrieve and to provide upon a request formulated by the Medical ractitioner all the available information concerning a patient who has received care in different health structures without divulging the patient's identity. Our method can lead to improved efficiency of personal medical record management under the mixed responsibilities of the patient and the MP.