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PubMed1981

[Robust estimation of fertility by the use of model stable populations].

"If we know the proportion of population under 15 years of age, the probability of newborns to reach 5 years of age and the rate of growth of that population, by means of a very simple procedure we can estimate the birth rate, the growth reproduction rate and the total fertility rate through the appropriate use of stable population models. Even if the real population is far from being a stable population the estimates are very little affected, which shows the robustness of the procedure." (summary in ENG)

Birth Rate↗
PubMedDate not supplied

On a method of robust standardization.

"The need of summary measures of the incidence of a phenomenon independent of age structure (composition) and other compositional factors is noted in demographic literature. One such index is developed in this paper. A standardized index is defined as robust, if it is least sensitive [to] the age structure of the standard population. The Banerjee-Stuvel price index is shown to have this property by a computer simulation experiment."

Age Distribution↗
PubMed2002

Complete and robust ovulation inhibition with NuvaRing.

NuvaRing, a novel contraceptive vaginal ring, releases 15 microgram of ethinylestradiol (EE) and 120 microgram etonogestrel (ENG) per day. A randomized pharmacokinetic study compared NuvaRing with a combined oral contraceptive (COC) containing 30 microgram EE and 150 microgram desogestrel. Maximum levels of EE and ENG with NuvaRing were 30% and 40%, respectively, of those seen with the COC. Because ENG bioavailability was higher following vaginal administration, the systemic progestogen exposures were comparable with the two contraceptives. However, the EE bioavailabilities were similar with both routes and so EE exposure with NuvaRing was half that with the COC. Pharmacodynamic studies have examined ovarian function during recommended and altered NuvaRing use. The use of NuvaRing for the recommended 3-week period completely inhibited ovulation. During an additional 2 weeks of use, ovulation continued to be inhibited. Early NuvaRing removal after just 3 days had no effect on the time to ovulation compared with recommended use, thus indicating that 3 days of use seem to be sufficient to suppress ovarian activity. Finally, delayed ring insertion (when the follicles had developed to 13 mm) resulted in inhibition of ovulation in all women. In conclusion, NuvaRing effectively inhibits ovulation during recommended and altered use, showing that it is a robust contraceptive method.

Biological Availability↗
PubMed2003

The Wlds mutation delays robust loss of motor and sensory axons in a genetic model for myelin-related axonopathy.

Mice deficient in the peripheral myelin component P0 mimic severe forms of inherited peripheral neuropathies in humans, with defective myelin formation and consequent axonal loss. We cross-bred these mice with the spontaneous mutant C57BL/Wld(s) typically showing protection from Wallerian degeneration because of fusion of the ubiquitination factor E4B (Ube4b) and nicotinamide mononucleotide adenylyltransferase (Nmnat) genes. We found that in the double mutants, the robust myelin-related axonal loss is reduced at 6 weeks and 3 months of age. Moreover, retrograde labeling from plantar nerves revealed an increased survival of motor axons. These motor axons appeared functionally active because both the amplitude of compound muscle action potentials and muscle strength were less reduced in the double mutants. At 6 months of age, reduction of axonal loss was no longer detectable in the double mutants when compared with littermates carrying the P0 null mutation only, although the Wld(s) gene was not reduced in its expression at this age. We conclude that myelin-related axonal loss is a process having some features in common with Wallerian degeneration. Introducing the Wld(s) gene would be a promising approach to delaying detrimental axonal loss in myelin disorders.

Action Potentials↗
PubMed2003

The conjunction effect: new evidence for robustness.

Five studies investigated the conjunction effect (or conjunction fallacy), in which participants report that the conjunction of two events is more rather than less likely than one of the events alone. There was no evidence that feedback or monetary reinforcement for correct answers affected students' performance on conjunction problems. Under some circumstances the context in which the conjunction problem was presented (after questions emphasizing logic or questions emphasizing opinions) affected occurrence of the effect. Location of the conjunction among the statements being rated had a significant effect. The effect occurred with or without a framing description and whether the conjunction consisted of two or three simple statements. However, statements representing the conjunction of three simple statements were (appropriately) judged less likely than those representing the conjunction of two simple statements. The substantial incidence of the effect, even without the descriptive frame and even when incentive and feedback were provided for correct answers, argues for its robustness.

California↗
PubMed2002

A more robust predictor of ideomotor dyspraxia: study on an alternative scoring method of the Bergès-Lézine's Imitation of Gestures test.

Use of the traditional Bergès-Lézine standardization [Test d'imitation de gestes (1963).] allowed us to confirm praxic disorders in children who are encountering obvious motor difficulties. However, in comparison to other neuropsychological assessments carried out on these children, it does not enable us to precociously pinpoint disorders in praxic organization. By means of a newly evaluated method (1997) developed on the basis of the Bergès-Lézine Imitation of Gestures test (1963), we retroactively assessed a group of children (N=10) who had been observed in a longitudinal study at the age of 3-5 years and at 7-8 years and assessed with the Bergès-Lézine version (1963) of the Imitation of Gestures test. Our revised test (1997) takes into account the quantitative factor of success, as well as the qualitative factor of movement planning. It facilitates the early detection of motor organization disorders, in correlation with other neuropsychological assessments carried out on these children. Comparative clinical findings with the same group of children tested using the Bergès-Lézine version and ours indicate that our version detects, more robustly, children encountering difficulties resulting from ideomotor dyspraxia, not identified by the Bergès-Lézine test (1963). Our alternative scoring method of Bergès-Lézine's test contributes largely to early detection of instrumental difficulties in children. Additionally, its predictive capacity makes it possible to apprehend disorders in distal and digital neuromotor functions.

Journal Article↗
PubMed2003

Robust regulation of anaerobic digestion processes.

This paper deals with the problem of controlling anaerobic digestion processes. A two-step (i.e. acidogenesis-methanization) mass balance model is considered for a 1 m3 fixed bed digester treating industrial wine distillery wastewater. The control law aims at regulating the organic pollution level while avoiding washout of biomass. To this end, a simple output feedback controller is considered which regulates a variable strongly related to the Chemical Oxygen Demand (COD). Numerical simulations assuming noisy measurements first illustrate the robustness of this control procedure. Then, the regulating procedure is implemented on the considered anaerobic digestion process in order to validate and demonstrate its efficiency in real life experiments.

Bacteria, Anaerobic↗
PubMed2003

Robust in vitro replication of Plasmodium falciparum in glycosyl-phosphatidylinositol-anchored membrane glycoprotein-deficient red blood cells.

Red blood cells (RBCs) infected with Plasmodium falciparum are protected from complement-mediated lysis by surface membrane glycosyl-phosphatidylinositol (GPI)-anchored proteins, which include decay accelerating factor (DAF or CD55) and CD59. To determine if P. falciparum avoids or replicates less efficiently in GPI protein-deficient cells at a higher risk for complement-mediated lysis, we compared P. falciparum infectivity among control RBCs with those from subjects with paroxysmal nocturnal hemoglobinuria (PNH), a condition in which RBCs express variable levels of DAF (negative and positive) and CD59 (negative [-], intermediate [I], and high [H]). Co-cultures of 19 matched samples of control and PNH RBCs were infected with P. falciparum to directly compare parasitic invasion. Each PNH RBC sample was then assessed for P. falciparum infectivity across the spectrum of GPI protein deficiency. Identification methods included biotin-streptavidin for RBC populations, fluorescein isothiocyanate-labeled antibodies to DAF and CD59, hydroethidine for parasite DNA, and flow cytometry. The mean +/- SD parasitemias in co-cultured PNH and control RBCs were 24.7 +/- 6.9% versus 21.0 +/- 5.9% (P = 0.12). For individual PNH samples, parasitemias were significantly higher in DAF (-) cells versus DAF (+) cells (25.0 +/- 8.9% versus 19.1 +/- 8.7%; P < 0.001) and in CD59 (-) cells versus I/H cells (22.5 +/- 6.4% versus 17.6 +/- 4.2%; P < 0.0003). Across the CD59 spectrum, mean parasitemias were highest in CD59 (-) cells (24.5 +/- 6.4%), followed by CD59-H cells (19.5 +/- 5.4%), and CD59-I cells (16.4 +/- 4.8%). Expression of DAF in 12 (63%) of 19 infected PNH samples was reduced. Thus, P. falciparum does not selectively avoid RBCs with fewer GPI proteins and parasite replication in PNH cells is at least as robust as in normal RBCs.

Animals↗
PubMed2004

Optimal but robust N and P removal in Sbrs: a model-based systematic study of operation scenarios.

A systematic approach to determine the optimal operation strategy for nitrogen (N) and phosphorus (P) removal of sequencing batch reactors (SBRs) has been developed and applied successfully to a lab-scale SBR. The methodology developed is based on using a grid of possible scenarios to simulate the effect of the key degrees of freedom in the SBR system. The grid of scenarios is simulated using a calibrated ASM2dN model developed and calibrated in a previous study. Effluent quality in combination with a robustness index for each of the scenarios is used to select the best scenario. With the best scenario, it is possible to improve/increase the current performance of the SBR system by around 54% and 74% for N and P removal respectively.

Bioreactors↗
PubMed2005

An automatic robust meshing algorithm for soft tissue modeling.

Soft tissue simulation with the finite element method is based on discretizations of anatomical objects. The structure of organs is mostly heterogeneous. To compute the deformation of composite materials correctly borders between adjacent tissues must be preserved. In this paper a new meshing algorithm is presented that fulfill this requirement. Additionally it works automatically in a straight forward manner to produce high quality 3d meshes from input triangle surfaces. The algorithm shows robust behavior and allows even to generate mesh from the most complex geometries. The processing time depends directly on the size of the input mesh and not on topology. This makes this algorithm calculable hence useful for time dependent cases, for example to adapt intraoperatively to modified operation status.

Algorithms↗
PubMed2005

The israeli virtual national health record: a robust national health information infrastructure based on a firm foundation of trust.

In many developed countries, a coordinated effort is underway to build national and regional Health Information Infrastructures (HII) for the linking of disparate sites of care, so that an access to a comprehensive Health Record will be feasible when critical medical decisions are made [1]. However, widespread adoption of such national projects is hindered by a series of barriers- regulatory, technical, financial and cultural. Above all, a robust national HII requires a firm foundation of trust: patients must be assured that their confidential health information will not be misused and that there are adequate legal remedies in the event of inappropriate behavior on the part of either authorized or unauthorized parties[2].The Israeli evolving National HII is an innovative state of the art implementation of a wide-range clinical inter-organizational data exchange, based on a unique concept of virtually temporary sharing of information. A logically connection of multiple caregivers and medical organizations creates a patient-centric virtual repository, without centralization. All information remains in its original format, location, system and ownership. On demand, relevant information is instantly integrated and delivered to the point of care. This system, successfully covering more than half of Israel's population, is currently evolving from a voluntary private-public partnership (dbMOTION and CLALIT HMO) to a formal national reality. The governmental leadership, now taking over the process, is essential to achieve a full potential of the health information technology. All partners of the Israeli health system are coordinated in concert with each other, driven with a shared vision - realizing that a secured, private, confidential health information exchange is assured.

Confidentiality↗
PubMed2005

Robust interval-based regulation for anaerobic digestion processes.

A robust regulation law is applied to the stabilization of a class of biochemical reactors exhibiting partially known highly nonlinear dynamic behavior. An uncertain environment with the presence of unknown inputs is considered. Based on some structural and operational conditions, this regulation law is shown to exponentially stabilize the aforementioned bioreactors around a desired set-point. This approach is experimentally applied and validated on a pilot-scale (1 m3) anaerobic digestion process for the treatment of raw industrial wine distillery wastewater where the objective is the regulation of the chemical oxygen demand (COD) by using the dilution rate as the manipulated variable. Despite large disturbances on the input COD and state and parametric uncertainties, this regulation law gave excellent performances leading the output COD towards its set-point and keeping it inside a pre-specified interval.

Bacteria, Anaerobic↗
PubMed2006

Online robust model estimation during in vivo needle insertions.

Soft tissue modeling is of key importance in medical robotics and simulation. In the case of percutaneous operations, a fine model of layers transitions and target tissues is required. However, the nature and the variety of these tissues is such that this problem is extremely complex. In this article, we propose a method to estimate the interaction between in vivo tissues and a surgical needle. The online robust estimation of a varying parameters model is achieved during an insertion in standard operating conditions.

Computer Simulation↗
PubMed2006

Conservation of glycolytic oscillations in Saccharomyces cerevisiae and human pancreatic beta-cells: a study of metabolic robustness.

The present study compares two computer models of the first part of glucose catabolism in different organisms in search of evolutionarily conserved characteristics of the glycolysis cycle and proposes the main parameters that define the stable steady-state or oscillatory behavior of the glycolytic system. It is suggested that in both human pancreatic beta-cells and Saccharomyces cerevisiae there are oscillations that, despite differences in wave form and period of oscillation, share the same robustness strategy: the oscillation is not controlled by only one but by at least two parameters that will have more or less control over the pathway flux depending on the initial state of the system as well as on extra-cellular conditions. This observation leads to two important interpretations: the first is that in both S. cerevisiae and human beta-cells, despite differences in enzyme kinetics and mechanism of feedback control, evolution seems to have kept an oscillatory behavior coupled to the glucose concentration outside the cytoplasm, and the second is that the development of drugs to regulate metabolic dysfunctions in more complex systems may require further study, not only determining which enzyme is controlling the flux of the system but also under which conditions and how its control is maintained by the enzyme or transferred to other enzymes in the pathway as the drug starts acting.

Computer Simulation↗
PubMed1991

The development of afferent projections to the robust archistriatal nucleus in male zebra finches: a quantitative electron microscopic study.

Because the projections into the robust nucleus of the archistriatum (RA) are thought to play important roles in song learning and sexual differentiation of the zebra finch (Poephila guttata), quantitative electron microscopic techniques were used to measure the development of synaptic input to the neuropil of RA in this species. Two nuclei [hyperstriatum ventrale pars caudalis (HVc) and lateral magnocellular nucleus of the anterior neostriatum (IMAN)] that send projections to RA were lesioned at each of three different ages: 25 d after hatching, 53 d, and adulthood. In tissue from RA processed for conventional electron microscopy, lesion-induced degeneration was used to identify synapses from either HVc or IMAN. Axosomatic synapses were excluded from analysis. In control (unlesioned) animals, the density of synapses in neuropil increased slightly between days 28 and 56 and remained constant thereafter. Because of a large increase in the volume of RA, the total number of synapses in neuropil of RA tripled between days 28 and 56 and decreased significantly between day 56 and adulthood. The density and total number of synapses in neuropil originating from HVc increased significantly between days 25 and 53, but did not change significantly thereafter. In contrast, the density and total number of synapses from IMAN decreased significantly between days 25 and 53 and did not change thereafter. Presynaptic terminals from IMAN were larger than those from HVc. These data demonstrate that the most rapid phase of song learning is accompanied by a major rearrangement of synaptic contacts into RA that stem from HVc and IMAN.

Afferent Pathways↗
PubMed1990

Testing the robustness of the diagnostic overshadowing bias.

The robustness of the diagnostic overshadowing bias was examined by (a) testing the relation of overshadowing to level of mental retardation, (b) reexamining the effect of clinical experience in a more sensitive analysis, and (c) extending previous results to rehabilitation counselors. Diagnostic overshadowing was found with individuals with an IQ of 58, but did not generalize to those with IQs 70 or 80. This finding does not support the saliency hypothesis proposed by Reiss and his colleagues. In contrast to earlier studies, experience was related to overshadowing, although results were mixed. Experience measured by number of clients seen was not significant, whereas longevity in the field of mental retardation was associated with increased overshadowing.

Adaptation, Psychological↗
PubMedDate not supplied

The effects of hydropenia, volume expansion, interstitial pressures, excluded volumes, and venous pressures on the robustness of capillary filtration coefficient determination.

The measurement of peripheral capillary filtration coefficient (Kf) by venous occlusion methods presupposes that filtration equilibrium does not occur along the length of the filtering surface, since this would result in an unpredictably low estimate for Kf. Filtration equilibrium occurs if the ratio of plasma flow (Q) to Kf is less than a critical value previously estimated to be between 200 and 250 mmHg. The minimum Q/Kf was reevaluated, taking into account the nonlinear relationship between protein concentration and oncotic pressure, changes in interstitial fluid hydrostatic and oncotic pressure, interstitial excluded volume, whether hydropenia or volume expansion is present, and whether the induced venous pressure change is low (10 mmHg) or high (40 mmHg). In all conditions the minimum Q/Kf ranged from 10 to 20 mmHg, while experimental conditions commonly have Q/Kf ratios from 1200 to 1500 mmHg. Thus, filtration equilibrium is unlikely to occur during Kf determinations under any circumstances in a living organism. Kf methodology is considerably more robust than previously reported.

Animals↗