903 resultados para Molécules du CMH II non-classiques


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The effect of conduction-convection-radiation on natural convection flow of Newtonian optically thick gray fluid, confined in a non-Darcian porous media square cavity is numerically studied. For the gray fluid consideration is given to Rosseland diffusion approximation. Further assuming that (i) the temperature of the left vertical wall is varying linearly with height, (ii) cooled right vertical and top walls and (iii) the bottom wall is uniformly-heated. The governing equations are solved using the Alternate Direct Implicit method together with the Successive Over Relaxation technique. The investigation of the effect of governing parameters namely the Forschheimer resistance (Γ), the Planck constant (Rd), and the temperature difference (Δ), on flow pattern and heat transfer characteristics has been carried out. It was seen that the reduction of flow and heat transfer occurs as the Forschheimer resistance is increased. On the other hand both the strength of flow and heat transfer increases as the temperature ratio, Δ, is increased.

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There are different ways to authenticate humans, which is an essential prerequisite for access control. The authentication process can be subdivided into three categories that rely on something someone i) knows (e.g. password), and/or ii) has (e.g. smart card), and/or iii) is (biometric features). Besides classical attacks on password solutions and the risk that identity-related objects can be stolen, traditional biometric solutions have their own disadvantages such as the requirement of expensive devices, risk of stolen bio-templates etc. Moreover, existing approaches provide the authentication process usually performed only once initially. Non-intrusive and continuous monitoring of user activities emerges as promising solution in hardening authentication process: iii-2) how so. behaves. In recent years various keystroke dynamic behavior-based approaches were published that are able to authenticate humans based on their typing behavior. The majority focuses on so-called static text approaches, where users are requested to type a previously defined text. Relatively few techniques are based on free text approaches that allow a transparent monitoring of user activities and provide continuous verification. Unfortunately only few solutions are deployable in application environments under realistic conditions. Unsolved problems are for instance scalability problems, high response times and error rates. The aim of this work is the development of behavioral-based verification solutions. Our main requirement is to deploy these solutions under realistic conditions within existing environments in order to enable a transparent and free text based continuous verification of active users with low error rates and response times.

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Boron nitride nanotubes were functionalized by microperoxidase-11 in aqueous media, showing improved catalytic performance due to a strong electron coupling 10 between the active centre of microperoxidase-11 and boron nitride nanotubes. One main application challenge of enzymes as biocatalysts is molecular aggregation in the aqueous solution. This issue is addressed by immobilization of enzymes on solid supports which 15 can enhance enzyme stability and facilitate separation, and recovery for reuse while maintaining catalytic activity and selectivity. The protein-nanoparticle interactions play a key role in bio-nanotechnology and emerge with the development of nanoparticle-protein “corona”. Bio-molecular coronas provide a 20 unique biological identity of nanosized materials.1, 2 As a structural analogue to carbon nanotubes (CNTs), Boron nitride nanotubes have boron and nitrogen atoms distributed equally in hexagonal rings and exhibit excellent mechanical strength, unique physical properties, and chemical stability at high-temperatures. 25 The chemical inertness of BN materials suits to work in hazardous environments, making them an optimal candidate in practical applications in biological and medical field.3, 4

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Background Currently the best prognostic index for operable non-small cell lung cancer (NSCLC) is the TNM staging system. Molecular biology holds the promise of predicting outcome for the individual patient and identifying novel therapeutic targets. Angiogenesis, matrix metalloproteinases (MMP)-2 and -9, and the erb/HER type I tyrosine kinase receptors are all implicated in the pathogenesis of NSCLC. Methods A retrospective analysis of 167 patients with resected stage I-IIIa NSCLC and >60 days postoperative survival with a minimum follow up of 2 years was undertaken. Immunohistochemical analysis was performed on paraffin embedded sections for the microvessel marker CD34, MMP-2 and MMP-9, EGFR, and c-erbB-2 to evaluate the relationships between and impact on survival of these molecular markers. Results Tumour cell MMP-9 (HR 1.91 (1.23-2.97)), a high microvessel count (HR 1.97 (1.28-3.03)), and stage (stage II HR 1.44 (0.87-2.40), stage IIIa HR 2.21 (1.31-3.74)) were independent prognostic factors. Patients with a high microvessel count and tumour cell MMP-9 expression had a worse outcome than cases with only one (HR 1.68 (1.04-2.73)) or neither (HR 4.43 (2.29-8.57)) of these markers. EGFR expression correlated with tumour cell MMP-9 expression (p<0.001). Immunoreactivity for both of these factors within the same tumour was associated with a poor prognosis (HR 2.22 (1.45-3.41)). Conclusion Angiogenesis, EGFR, and MMP-9 expression provide prognostic information independent of TNM stage, allowing a more accurate outcome prediction for the individual patient. The development of novel anti-angiogenic agents, EGFR targeted therapies, and MMP inhibitors suggests that target specific adjuvant treatments may become a therapeutic option in patients with resected NSCLC.

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Purpose: In non-small-cell lung cancer (NSCLC), the epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) play major roles in tumorigenesis. This phase I/II study evaluated combined therapy with the EGFR tyrosine kinase inhibitor (TKI) gefitinib and the COX-2 inhibitor rofecoxib in platinum-pretreated, relapsed, metastatic NSCLC (n = 45). Patients and Methods: Gefitinib 250 mg/d was combined with rofecoxib (dose escalated from 12.5 to 25 to 50 mg/d through three cohorts, each n = 6). Because the rofecoxib maximum-tolerated dose was not reached, the 50 mg/d cohort was expanded for efficacy evaluation (n = 33). Results: Among the 42 assessable patients, there was one complete response (CR) and two partial responses (PRs) and 12 patients with stable disease (SD); disease control rate was 35.7% (95% CI, 21.6% to 52.0%). Median time to tumor progression was 55 days (95% CI, 47 to 70 days), and median survival was 144 days (95% CI, 103 to 190 days). In a pilot study, matrix-assisted laser desorption/ionization (MALDI) proteomics analysis of baseline serum samples could distinguish patients with an objective response from those with SD or progressive disease (PD), and those with disease control (CR, PR, and SD) from those with PD. The regimen was generally well tolerated, with predictable toxicities including skin rash and diarrhea. Conclusion: Gefitinib combined with rofecoxib provided disease control equivalent to that expected with single-agent gefitinib and was generally well tolerated. Baseline serum proteomics may help identify those patients most likely to benefit from EGFR TKIs. © 2007 by American Society of Clinical Oncology.

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Zinc oxide (ZnO) that contains non-magnetic ionic dopants, such as nitrogen (N)-doped zinc oxide (ZnO:N), has been observed to exhibit ferromagnetism. Ferromagnetism is proposed to arise from the Coulomb excitation in the localized states that is induced by the oxygen vacancy, V O. A model based on the Coulomb excitation that is associated with the electron–phonon interaction theoretically explains the ferromagnetic mechanism of ZnO:N. This study reveals that the ferromagnetism will be induced by either deep localized states with a small V O concentration or shallow localized states with a high V O concentration. Additionally, electron–phonon coupling either suppresses the ferromagnetism that is induced by the deep donor states of V O or enhances the ferromagnetism that is induced by the shallow donor states of V O.

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OBJECTIVES: Four randomized phase II/III trials investigated the addition of cetuximab to platinum-based, first-line chemotherapy in patients with advanced non-small cell lung cancer (NSCLC). A meta-analysis was performed to examine the benefit/risk ratio for the addition of cetuximab to chemotherapy. MATERIALS AND METHODS: The meta-analysis included individual patient efficacy data from 2018 patients and individual patient safety data from 1970 patients comprising respectively the combined intention-to-treat and safety populations of the four trials. The effect of adding cetuximab to chemotherapy was measured by hazard ratios (HRs) obtained using a Cox proportional hazards model and odds ratios calculated by logistic regression. Survival rates at 1 year were calculated. All applied models were stratified by trial. Tests on heterogeneity of treatment effects across the trials and sensitivity analyses were performed for all endpoints. RESULTS: The meta-analysis demonstrated that the addition of cetuximab to chemotherapy significantly improved overall survival (HR 0.88, p=0.009, median 10.3 vs 9.4 months), progression-free survival (HR 0.90, p=0.045, median 4.7 vs 4.5 months) and response (odds ratio 1.46, p<0.001, overall response rate 32.2% vs 24.4%) compared with chemotherapy alone. The safety profile of chemotherapy plus cetuximab in the meta-analysis population was confirmed as manageable. Neither trials nor patient subgroups defined by key baseline characteristics showed significant heterogeneity for any endpoint. CONCLUSION: The addition of cetuximab to platinum-based, first-line chemotherapy for advanced NSCLC significantly improved outcome for all efficacy endpoints with an acceptable safety profile, indicating a favorable benefit/risk ratio.

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The non-8-enoate anion undergoes losses of the elements of C3H6, C4H8 and C6H12 on collisional activation, The mechanisms of these processes have been elucidated by a combination of product ion and labelling (H-2 and C-13) studies, together with a neutralisation reionisation mass spectrometric study. These studies allow the following conclusions to be made. (i) The loss of C3H6 involves cyclisation of the enolate anion of non-8-enoic acid to yield the cyclopentyl carboxylate anion and propene. (ii) The loss of 'C4H8' is a charge-remote process (one which proceeds remote from the charged centre) which yields the pent-4-enoate anion, butadiene and dihydrogen. This process co-occurs and competes with complex H scrambling. (iii) The major loss of 'C6H12' occurs primarily by a charge-remote process yielding the acrylate anion, hexa-1,5-diene and dihydrogen, but in this case no H scrambling accompanies the process. (iv) It is argued that the major reason why the two charge-remote processes occur in preference to anion-induced losses of but-l-ene and hex-l-ene from the respective 4- and 2-anions is that although these anions are formed, they have alternative and lower energy fragmentation pathways than those involving the losses of but-l-ene and hex-l-ene; viz. the transient 4-anion undergoes facile proton transfer to yield a more stable anion, whereas the 2-(enolate) anion undergoes preferential cyclisation followed by elimination of propene [see (i) above].

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This paper sets out to contribute to the literature on the design and the implementation of management control systems. To this end, we question what is discussed when a management control system is to be chosen and on what decision-making eventually rests. This study rests upon an ethnomethodology of the Salvation Army’s French branch. Operating in the dual capacity of a researcher and a counsellor to management, between 2000 and 2007, we have unrestricted access to internal data revealing the backstage of management control: discussions and interactions surrounding the choosing of control devices. We contribute to understanding the arising of a need for control, the steps and process followed to decide upon a management control system, and controls in nonprofits. [Cet article vise à contribuer à la littérature sur la mise en place des systèmes de contrôle de gestion. À cette fin, nous questionnons ce qui est discuté lors du choix d’un système de contrôle et sur quoi repose in fine la décision. Cet article est fondé sur une approche ethnométhodologique de l’Armée du Salut en France permise par notre double qualité de chercheurs mais également de conseiller auprès de la direction de l’organisation entre 2000 et 2007. Un accès illimité à des données internes nous permet ainsi de mettre en lumière les aspects méconnus et invisibles du contrôle de gestion : les discussions et interactions entourant le choix d’outils. Nous contribuons à la compréhension de l’émergence du besoin de contrôle, des étapes et du processus de choix d’outils et enfin du contrôle de gestion dans une organisation à but non lucratif.]

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In part 1 of this update, we put forward the argument that integration in ERP based environments can be achieved in ways other than adopting a software configuration only approach. We drew on evidence from two large ERP implementations to show how, despite the cost implications, some customization, if carefully managed, could prove helpful. In this, the final part of the update, we discuss the benefits, and potential pitfalls, involved in enacting a non-standard based integration strategy. This requires attention to a) broadening the integration definition; b) bringing legacy practices forward and c) developing a customization based integration strategy.

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Through an examination of Wallace v Kam, this article considers and evaluates the law of causation in the specific context of a medical practitioner’s duty to provide information to patients concerning material risks of treatment. To supply a contextual background for the analysis which follows, Part II summarises the basic principles of causation law, while Part III provides an overview of the case and the reasoning adopted in the decisions at first instance and on appeal. With particular emphasis upon the reasoning in the courts of appeal, Part IV then examines the implications of the case in the context of other jurisprudence in this field and, in so doing, provides a framework for a structured consideration of causation issues in future non-disclosure cases under the Australian civil liability legislation. As will become clear, Wallace was fundamentally decided on the basis of policy reasoning centred upon the purpose behind the legal duty violated. Although the plurality in Rogers v Whitaker rejected the utility of expressions such as ‘the patient’s right of self-determination’ in this context, some Australian jurisprudence may be thought to frame the practitioner’s duty to warn in terms of promoting a patient’s autonomy, or right to decide whether to submit to treatment proposed. Accordingly, the impact of Wallace upon the protection of this right, and the interrelation between it and the duty to warn’s purpose, is investigated. The analysis in Part IV also evaluates the courts’ reasoning in Wallace by questioning the extent to which Wallace’s approach to liability and causal connection in non-disclosure of risk cases: depends upon the nature and classification of the risk(s) in question; and can be reconciled with the way in which patients make decisions. Finally, Part V adopts a comparative approach by considering whether the same decision might be reached if Wallace was determined according to English law.

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The monoanionic ligand 1,1,3,3 tetracyano-2 ethoxypropenide (tcnoet) is reported with its Cu(II)–bpy complex of formula [Cu2(µ-tcnoet)2(tcnoet)2(bpy)2]. The structure has been determined using X-ray diffraction and features an alternating chain with bridging tcnoet ligands. One ligand acts as a bidentate, dinucleating ligand with one short Cu–N and one medium Cu–N bond, whereas the other tcnoet is largely monodentate, albeit with a very weak interdimer Cu–N bond. Despite the arrangement in dinuclear units, further arranged into linear chains through the non-bridging tcnoet ligand, the compound shows no significant magnetic exchange, as deduced from magnetic susceptibility down to 4 K. Ligand-field, IR and EPR spectra in the solid state and in frozen solution are reported and are consistent with the overall structure.

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Density functional theory (DFT) calculations were performed to study the structural, mechanical, electrical, optical properties, and strain effects in single-layer sodium phosphidostannate(II) (NaSnP). We find the exfoliation of single-layer NaSnP from bulk form is highly feasible because the cleavage energy is comparable to graphite and MoS2. In addition, the breaking strain of the NaSnP monolayer is comparable to other widely studied 2D materials, indicating excellent mechanical flexibility of 2D NaSnP. Using the hybrid functional method, the calculated band gap of single-layer NaSnP is close to the ideal band gap of solar cell materials (1.5 eV), demonstrating great potential in future photovoltaic application. Furthermore, strain effect study shows that a moderate compression (2%) can trigger indirect-to-direct gap transition, which would enhance the ability of light absorption for the NaSnP monolayer. With sufficient compression (8%), the single-layer NaSnP can be tuned from semiconductor to metal, suggesting great applications in nanoelectronic devices based on strain engineering techniques.

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To date, a number of two-dimensional (2D) topological insulators (TIs) have been realized in Group 14 elemental honeycomb lattices, but all are inversionsymmetric. Here, based on first-principles calculations, we predict a new family of 2D inversion-asymmetric TIs with sizeable bulk gaps from 105 meV to 284 meV, in X2–GeSn (X = H, F, Cl, Br, I) monolayers, making them in principle suitable for room-temperature applications. The nontrivial topological characteristics of inverted band orders are identified in pristine X2–GeSn with X = (F, Cl, Br, I), whereas H2–GeSn undergoes a nontrivial band inversion at 8% lattice expansion. Topologically protected edge states are identified in X2–GeSn with X = (F, Cl, Br, I), as well as in strained H2–GeSn. More importantly, the edges of these systems, which exhibit single-Dirac-cone characteristics located exactly in the middle of their bulk band gaps, are ideal for dissipationless transport. Thus, Group 14 elemental honeycomb lattices provide a fascinating playground for the manipulation of quantum states.

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Background. Rheumatoid arthritis (RA) is strongly associated with a series of HLA-DRB1 alleles that encode a conserved sequence of amino acids (70Q/R K/R R A A74) in the DRβ1 chain, known as the shared epitope (SE). However 30% of patients are negative for DRB1*04 and 15% are SE-negative. Exposure to these alleles as non-inherited maternal antigens (NIMA) might explain this discrepancy. We undertook a family study to investigate the role of NIMA in RA. Methods. One hundred families, including the RA proband and both parents, were recruited. HLA-DRB1 genotyping was performed using an allele-specific polymerase chain reaction by standard methods. The frequencies of NIMA and non-inherited paternal antigens (NIPA) were compared using contingency tables and a two-tailed P test. We then reviewed four previously published studies of NIMA in RA and conducted an analysis of the combined data Results. We identified 36 families in which the proband was DRB1*04-negative and 13 in which the proband lacked the SE. There was an excess of DRB1*04 and SE NIMA (P=0.05) compared with NIPA. Combined analysis with previous studies showed that 53/231 mothers (23%) versus 25/205 fathers (12%) had a non-inherited DRB1*04 (P=0.003) and 30/99 mothers versus 18/101 fathers had a non-inherited SE allele (P=0.03). Conclusion. A role for HLA NIMA in RA is suggested by these results.