
Université Le Havre Normandie
UniversityLe Havre, France
Research output, citation impact, and the most-cited recent papers from Université Le Havre Normandie (France). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Université Le Havre Normandie
Experimental measurements of acoustic transmission through a solid-solid two-dimensional binary-composite medium constituted of a triangular array of parallel circular steel cylinders in an epoxy matrix are reported. Attention is restricted to propagation of elastic waves perpendicular to the cylinders. Measured transmitted spectra demonstrate the existence of absolute stop bands, i.e., band gaps independent of the direction of propagation in the plane perpendicular to the cylinders. Theoretical calculations of the band structure and transmission spectra using the plane wave expansion and the finite difference time domain methods support unambiguously the absolute nature of the observed band gaps.
Our vision of cancer has changed during the past decades. Indeed tumors are now perceived as complex entities where tumoral and stromal components interact closely. Among the different elements of tumor stroma the cellular component play a primordial role. Bone Marrow derived mesenchymal cells (MSCs) are attracted to tumor sites and support tumor growth. Endothelial cells (ECs) play a major role in angiogenesis. While the literature documents many aspects of the cross talk between stromal and cancer cells, the role of direct hetero-cellular contact is not clearly established. Recently, Tunneling nanotubes (TnTs) have been shown to support cell-to-cell transfers of plasma membrane components, cytosolic molecules and organelles within cell lines. Herein, we have investigated the formation of heterocellular TnTs between stromal (MSCs and ECs) and cancer cells. We demonstrate that TnTs occur between different cancer cells, stromal cells and cancer-stromal cell lines. We showed that TnTs-like structure occurred in 3D anchorage independent spheroids and also in tumor explant cultures. In our culture condition, TnTs formation occurred after large membrane adhesion. We showed that intercellular transfers of cytoplasmic content occurred similarly between cancer cells and MSCs or ECs, but we highlighted that the exchange of mitochondria occurred preferentially between endothelial cells and cancer cells. We illustrated that the cancer cells acquiring mitochondria displayed chemoresistance. Our results illustrate the perfusion-independent role of the endothelium by showing a direct endothelial to cancer cell mitochondrial exchange associated to phenotypic modulation. This supports another role of the endothelium in the constitution of the metastatic niche.
Observations made using AFM and SEM have been combined in order to study the structure of asphalts. Fluorescence microscopy was used to aid in understanding the structural changes occurring when polymer is added to the asphalts. With the atomic force microscope we are able to study the structure of the asphalts without any pre‐preparation. Despite very low resolution, our study reveal ed a network of asphaltene molecules with regard to asphalt gel. The same result is obtained by SEM observation but with a much better resolution. SEM observation, however, needs an adequate preparation method. In the presence of polymer we observed a rearrangement of the initial asphaltene association which leads to the assumption that polymer can aggregate the asphaltene phase.
Earthquakes represent one of the most catastrophic natural events affecting mankind. At present, a universally accepted risk mitigation strategy for seismic events remains to be proposed. Most approaches are based on vibration isolation of structures rather than on the remote shielding of incoming waves. In this work, we propose a novel approach to the problem and discuss the feasibility of a passive isolation strategy for seismic waves based on large-scale mechanical metamaterials, including for the first time numerical analysis of both surface and guided waves, soil dissipation effects, and adopting a full 3D simulations. The study focuses on realistic structures that can be effective in frequency ranges of interest for seismic waves, and optimal design criteria are provided, exploring different metamaterial configurations, combining phononic crystals and locally resonant structures and different ranges of mechanical properties. Dispersion analysis and full-scale 3D transient wave transmission simulations are carried out on finite size systems to assess the seismic wave amplitude attenuation in realistic conditions. Results reveal that both surface and bulk seismic waves can be considerably attenuated, making this strategy viable for the protection of civil structures against seismic risk. The proposed remote shielding approach could open up new perspectives in the field of seismology and in related areas of low-frequency vibration damping or blast protection.
This paper presents supercapacitor (SCAP) and battery modeling with an original energy management strategy in a hybrid storage technology. The studied dc power supply is composed of SCAPs and batteries. SCAPs are dimensioned for peak power requirement, and batteries provide the power in steady state. A bidirectional dc/dc converter is used between SCAPs and the dc bus. Batteries are directly connected to the dc bus. The originality of this study is focused on SCAP behavior modeling and energy management strategy. The proposed strategy is based on a polynomial (RST) controller. For reasons of cost and existing components (not optimized) such as batteries and semiconductors, the experimental test benches are designed in reduced scale. The characterized packs of SCAPs include two modules of ten cells in series for each one and present a maximum voltage of 27 V. The proposed strategy is implemented on a PIC18F4431 microcontroller for two dc/dc converter topology controls. Experimental and simulation results obtained from the polynomial control strategy are presented, analyzed, and compared with that of classical proportional-integral control.
This paper presents an energy management method in an electrical hybrid power source (EHPS) for electric vehicular applications. The method is based on the flatness control technique (FCT) and fuzzy logic control (FLC). This EHPS is composed of a fuel cell system as the main source and two energy storage sources (ESSs)-a bank of supercapacitors (SCs) and a bank of batteries (BATs)-as the auxiliary source. With this hybridization, the volume and mass of the EHPS can be reduced, because the high energy density of BAT and high power density of SC are utilized. In the proposed novel control strategy, the FCT is used to manage the energy between the main and the auxiliary sources, and the FLC is employed to share the power flow in the ESS between the SC and the BAT. The power sharing depends on the load power and the state of charge of the SC and the BAT. EHPS is controlled by the regulation of the stored electrostatic energy in the dc buses. The main property of this strategy is that the energy management in the power source is carried out with a single general control algorithm in different operating modes, consequently avoiding any algorithm commutation. An EHPS test bench has been assembled and equipped with a real-time system controller based on a dSPACE. The experimental results validate the efficiency of the proposed control strategy.
In this paper, the suitability of a class of electric machines for vehicle traction applications is discussed. These machines, which are known as hybrid excitation synchronous machines, combine permanent-magnet (PM) excitation with wound field excitation. The goal behind the principle of hybrid excitation is to combine the advantages of PM excited machines and wound field synchronous machines. It is shown that these machines have good flux weakening capability compared with PM machines, and that they constitute an energy-efficient solution for vehicle propulsion.
AIMS: To assess the frequency and cost of drug reactions causing or prolonging hospitalization. METHODS: All patients admitted to an internal medicine ward over 6 months were evaluated to identify serious adverse reactions. The number of drug classes on admission or at the time of the adverse drug reaction (ADR) was counted. Excess ADR-related hospital stay was computed using a) raw excess duration of hospital stay, b) correction of duration of hospital stay by age, sex, and number of drug classes, and c) estimation by investigator of excess hospital stay. RESULTS: Three hundred and twenty-nine patients were evaluated: 212 male, 117 female, mean age 57.2 (males: 52.2, females: 66.2 (P < 0.05)), range 17-95 years. They stayed a total of 3720 hospital days (mean stay 11.3 days). 298 had no ADR (mean age 55.8, taking a mean of 2.7 drug classes, 10.7 days hospital stay); 31 had ADRs: in 10, the ADR caused admission in patients with a mean age of 84 (P < 0.01 vs the two other groups), taking 6.3 drug classes, who stayed a mean of 15.1 days; 21 occurred in hospital in patients with a mean age of 63.6, taking 4.2 drug classes (P < 0.01), who stayed a mean of 19.2 days (P < 0.01 vs patients without ADRs). In four the ADR was fatal (13% of ADRs, 40% of deaths). Raw ADR-related excess hospital stay was 318 days (8.6% of all hospital days), after multivariate correction 282 days (7.6% of all hospital days), and with investigator estimation 197 days (5.3% of all hospital days). Point prevalence of ADRs at admission was 3%, incidence rate in hospital was 5.6/1000 patient-days. CONCLUSIONS: 3% of the admissions were related to ADRs. In addition, 6.6% of hospitalized patients had significant ADRs. Between 5 and 9% of hospital costs were related to ADRs. In 24 of the 31 patients with ADRs (77%), these were related to the pharmacological properties of the involved drugs, and may possibly have been avoidable.
In this paper, the authors propose two modeling procedures for wind speed simulation. These procedures could be implemented on the structure of a wind turbine simulator during studies concerning stand-alone or hybrid wind systems. The evolution of a horizontal wind speed has been synthesized taking into account two components. The medium- and long-term component is described by a power spectrum associated to a specific site. The turbulence component is assumed to be dependent on the medium- and long-term wind speed evolution. It is considered as a nonstationary process. Two simulation methods for this component, using rational and nonrational filters are proposed. In both procedures, the turbulence model is defined by two parameters, which are either obtained experimentally, or adopted a priori, according to information from the considered site. Numerical results and implementation aspects are also discussed.
We study an infection-age model of disease transmission, where both the infectiousness and the removal rate may depend on the infection age. In order to study persistence, the system is described using integrated semigroups. If the basic reproduction number R 0 < 1, then the disease-free equilibrium is globally asymptotically stable. For R 0 > 1, a Lyapunov functional is used to show that the unique endemic equilibrium is globally stable amongst solutions for which disease transmission occurs.
IMPORTANCE: Primary Sjögren syndrome is a systemic autoimmune disease characterized by mouth and eye dryness, pain, and fatigue. Hydroxychloroquine is the most frequently prescribed immunosuppressant for the syndrome. However, evidence regarding its efficacy is limited. OBJECTIVE: To evaluate the efficacy of hydroxychloroquine for the main symptoms of primary Sjögren syndrome: dryness, pain, and fatigue. DESIGN, SETTING, AND PARTICIPANTS: From April 2008 to May 2011, 120 patients with primary Sjögren syndrome according to American-European Consensus Group Criteria from 15 university hospitals in France were randomized in a double-blind, parallel-group, placebo-controlled trial. Participants were assessed at baseline, week 12, week 24 (primary outcome), and week 48. The last follow-up date for the last patient was May 15, 2012. INTERVENTIONS: Patients were randomized (1:1) to receive hydroxychloroquine (400 mg/d) or placebo until week 24. All patients were prescribed hydroxychloroquine between weeks 24 and 48. MAIN OUTCOMES AND MEASURES: The primary end point was the proportion of patients with a 30% or greater reduction between weeks 0 and 24 in scores on 2 of 3 numeric analog scales (from 0 [best] to 10 [worst]) evaluating dryness, pain, and fatigue. RESULTS: At 24 weeks, the proportion of patients meeting the primary end point was 17.9% (10/56) in the hydroxychloroquine group and 17.2% (11/64) in the placebo group (odds ratio, 1.01; 95% CI, 0.37-2.78; P = .98). Between weeks 0 and 24, the mean (SD) numeric analog scale score for dryness changed from 6.38 (2.14) to 5.85 (2.57) in the placebo group and 6.53 (1.97) to 6.22 (1.87) in the hydroxychloroquine group. The mean (SD) numeric analog scale score for pain changed from 4.92 (2.94) to 5.08 (2.48) in the placebo group and 5.09 (3.06) to 4.59 (2.90) in the hydroxychloroquine group. The mean (SD) numeric analog scale for fatigue changed from 6.26 (2.27) to 5.72 (2.38) in the placebo group and 6.00 (2.52) to 5.94 (2.40) in the hydroxychloroquine group. All but 1 patient in the hydroxychloroquine group had detectable blood levels of the drug. Hydroxychloroquine had no efficacy in patients with anti-SSA autoantibodies, high IgG levels, or systemic involvement. During the first 24 weeks, there were 2 serious adverse events in the hydroxychloroquine group and 3 in the placebo group; in the last 24 weeks, there were 3 serious adverse events in the hydroxychloroquine group and 4 in the placebo group. CONCLUSIONS AND RELEVANCE: Among patients with primary Sjögren syndrome, the use of hydroxychloroquine compared with placebo did not improve symptoms during 24 weeks of treatment. Further studies are needed to evaluate longer-term outcomes. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00632866.
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Purpose This paper aims to examine the role of attachment in consumer brand relationships and its links with constructs such as trust, satisfaction, commitment and behavioural loyalty. Design/methodology/approach This paper is based on exploratory and confirmatory studies that provide a model that explains the relationship between brand attachment and its outcomes. A structural equation modelling is used to assess the hypothetical links. Findings The findings of the structural model confirm the majority of the hypothesised relationships. Brand attachment is considered as an important input to brand commitment for utilitarian products. Originality/value Few studies have attempted to model the relationship between brand attachment and its antecedents and outcomes. This research also focused on a particular utilitarian product that is not – apparently – affect laden.
Colorectal cancers with microsatellite instability (MSI) represent 15% of all colorectal cancers, including Lynch syndrome as the most frequent hereditary form of this disease. Notably, MSI colorectal cancers have a higher density of tumor-infiltrating lymphocytes (TIL) than other colorectal cancers. This feature is thought to reflect the accumulation of frameshift mutations in sequences that are repeated within gene coding regions, thereby leading to the synthesis of neoantigens recognized by CD8(+) T cells. However, there has yet to be a clear link established between CD8(+) TIL density and frameshift mutations in colorectal cancer. In this study, we examined this link in 103 MSI colorectal cancers from two independent cohorts where frameshift mutations in 19 genes were analyzed and CD3(+), CD8(+), and FOXP3(+) TIL densities were quantitated. We found that CD8(+) TIL density correlated positively with the total number of frameshift mutations. TIL densities increased when frameshift mutations were present within the ASTE1, HNF1A, or TCF7L2 genes, increasing even further when at least one of these frameshift mutations was present in all tumor cells. Through in vitro assays using engineered antigen-presenting cells, we were able to stimulate peripheral cytotoxic T cells obtained from colorectal cancer patients with peptides derived from frameshift mutations found in their tumors. Taken together, our results highlight the importance of a CD8(+) T cell immune response against MSI colorectal cancer-specific neoantigens, establishing a preclinical rationale to target them as a personalized cellular immunotherapy strategy, an especially appealing goal for patients with Lynch syndrome.
We present the first astronomical detection of a diatomic negative ion, the cyanide anion CN<sup>-<sup/>, and quantum mechanical calculations of the excitation of this anion by means of collisions with para-H<sub>2<sub/>. The anion CN<sup>-<sup/> is identified by observing the <i>J<i/> = 2–1 and <i>J<i/> = 3–2 rotational transitions in the C-star envelope IRC +10216 with the IRAM 30-m telescope. The U-shaped line profiles indicate that CN<sup>-<sup/>, like the large anion C<sub>6<sub/>H<sup>-<sup/>, is formed in the outer regions of the envelope. Chemical and excitation model calculations suggest that this species forms from the reaction of large carbon anions with N atoms, rather than from the radiative attachment of an electron to CN, as is the case for large molecular anions. The unexpectedly high abundance derived for CN<sup>-<sup/>, 0.25% relative to CN, indicates that its detection in other astronomical sources is likely. A parallel search for the small anion C<sub>2<sub/>H<sup>-<sup/> remains inconclusive, despite the previous tentative identification of the <i>J<i/> = 1–0 rotational transition. The abundance of C<sub>2<sub/>H<sup>-<sup/> in IRC +10216 is found to be vanishingly small, <i><<i/>0.0014% relative to C<sub>2<sub/>H.
The BASECOL2012 database is a repository of collisional data and a web service within the Virtual Atomic and Molecular Data Centre (VAMDC, http://www.vamdc.eu). It contains rate coefficients for the collisional excitation of rotational, ro-vibrational, vibrational, fine, and hyperfine levels of molecules by atoms, molecules, and electrons, as well as fine-structure excitation of some atoms that are relevant to interstellar and circumstellar astrophysical applications. Submissions of new published collisional rate coefficients sets are welcome, and they will be critically evaluated before inclusion in the database. In addition, BASECOL2012 provides spectroscopic data queried dynamically from various spectroscopic databases using the VAMDC technology. These spectroscopic data are conveniently matched to the in-house collisional excitation rate coefficients using the SPECTCOL sofware package (http://vamdc.eu/software), and the combined sets of data can be downloaded from the BASECOL2012 website. As a partner of the VAMDC, BASECOL2012 is accessible from the general VAMDC portal (http://portal.vamdc.eu) and from user tools such as SPECTCOL.
This paper presents the energy management for the decentralized generation systems (DGS) using the wind turbine with photovoltaic (PV) panels and the energy storage devices. For a high penetration level of the wind/PV generation, the energy storage device with a fast response is necessary to cover the shortfall or overflow of generation due to sudden variations of the wind or the sun. In addition, the requested energy by the residential appliances presents random behavior, which can be lower or higher than the produced energy from the renewable sources. Using the wind turbine and the PV power generation system with energy storage will reduce the fluctuations of the wind power and the load ones. The energy storage system requires capital investment; thus, it is important to estimate the reasonable storage capacities without an overflow size for the desired applications. In addition, a good strategy for energy management is necessary to reduce the variation impacts of the wind energy and the load for the battery and the residential appliances. The contribution of this paper is focused on energy management based on the frequency approach using the wind/load's fluctuating power sharing and the polynomial controllers. First, this method enables reducing for the battery and the microgrid the impacts of the microcycles due to the wind/load's power fluctuations. Second, it allows estimating the energy storage capacity without the overflow size. The performances of the proposed method are evaluated through some simulations and experimental tests using the summer load profile and the winter ones.
Abstract The study explores the influence of contextual factors surrounding production planning and green strategic investment decision‐making practices (GSIDMP) in UK companies. We utilize a mixed‐method approach as a research methodology to study the current trend of production planning and GSIDMP. This study's conceptual model is rooted conspicuously in the resource‐based theory (RBT), natural‐resource‐based view, and dynamic capabilities. We empirically examine the nexus among GSIDMP, technological innovation, dynamic capability, and companies' performance. Our study was based on a sample selected from UK‐listed companies, FTSE ALL‐Share Index for the period (2012–2021). Also, the study utilizes data from the UK Innovation Survey (2018–2020) and corporate disclosure through companies' annual reports as a complementary approach for data collection. Findings of this study explore the interdependencies among company dynamic capability, advanced technological innovation and governance mechanisms, and their mediation influence on the nexus between GSIDMP and companies' performance. This study sheds lights on current business innovation strategies. Findings reveal how current practices of production planning and GSIDM in large UK companies shaped by boardrooms absorptive and adaptive capabilities, knowledge‐generating and knowledge‐collaboration capabilities, technological adoption, and corporate governance mechanisms. This study offers insight regarding boardrooms proactive engagement in exploration and exploitation activities to strengthen ambidexterity through various innovation trajectories associated with green production and GSIDMP towards sustainability. We provide managerial implications for decision‐makers, regulators, investors, scholars, and other stakeholders.
The bases for the internationalization of the port terminal industry are explored. While the industry is being transformed by the penetration of transnational companies, there are important regional differences between Europe and North America. In Europe, the lead actors are companies that have arisen out of the industry itself, whereas in North America, most of the new actors are shipping lines. The consequences of this differentiation are substantial, since they represent fundamentally different types of organization, one being a product of horizontal integration based on multi‐user berth operations, the other being an outcome of vertical integration and oriented towards dedicated berth use. The dissimilarities are explained in terms of governance, competition and capacity. Intraregional differences are also examined through the case of France, where an unwillingness to open French ports to global operators has affected the performance of those ports. The paper concludes by discussing some of the implications of the findings, including the issue of monopoly control of ports and the potential for conflict between the two models of contemporary cargo handling.