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The purpose of the methodology described in this paper is to highlight an effective method for the organization of research results into written and oral forms. Authorities within supervising universities have realized that strong research by a candidate is often obscured by poor presentation, leading to the paper being ignored by the research community and journal reviewers. On the basis of their academic background, the writers of this paper decided to form a set of clear guidelines for writing research papers and giving oral presentations aimed at helping Ph.D. students. To support the effectiveness of the methodology proposed, a statistical analysis has been conducted. The methodology described in this paper was initially intended for use in the fields of computer engineering; however, it is applicable more widely. In conclusion, if the methodology reported in this paper is followed strictly, it is much less likely that a good piece of work would be rejected for publication, and/or remain anonymous, due to inadequate presentation.  相似文献   
33.
Recently we showed that coatings, prepared by unbalanced magnetron sputtering from a metallic Cr target in an Ar/CH4 discharge are composed of nanocrystalline CrC x embedded in an a-C:H matrix. This work investigates the structural correlation of such nanocomposite CrC x /a-C:H coatings to their tribological properties. Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) were used to characterize the phase composition and the chemical bonding in the films deposited at different experimental conditions. The coating microstructure was investigated on selected samples by high-resolution transmission electron microscopy. For CrC x -dominated coatings deposited at CH4 partial to total pressure ratios (pCH4/pt) < 0.42, only minor changes regarding the friction coefficients and the abrasive wear rates were observed although microstructural changes towards a higher degree of crystallinity were proven by transmission electron microscopy and substantiated with XPS results. For a-C:H dominated coatings deposited at pCH4/pt > 0.42, the friction coefficients and abrasive wear rates were shown to decrease with increasing a-C:H phase content and its more sp2-like bonding configuration. It can be concluded that the microstructural changes in terms of CrC x crystallite coarsening and bonding configuration of the a-C:H matrix phase are responsible for the observed changes of the friction coefficients and wear rates.  相似文献   
34.
Secondary leukaemia has rarely been reported as a complication of autologous stem cell transplantation for AML. We report two cases of AML who presented with well-characterised cytogenetic abnormalities at presentation: t(8;21) and t(15;17) respectively, and who, after achieving complete morphological and cytogenetic remissions post-autograft, developed MDS/AML associated with monosomy 7. This secondary change is most frequently seen following alkylating agent therapy for solid tumours. The secondary leukaemia seen in our patients may thus be due to exposure of the residual stem cells to the alkylating agents used in the transplant conditioning.  相似文献   
35.
Dental implant is a biocompatible titanium device surgically placed into the jaw bone to support a prosthetic tooth crown in order to replace missing teeth. However, placement of an implant changes the normal mechanical environment of jawbone, which causes the bone density to redistribute and adapt to the new environment by remodelling. This study aims to predict the density distribution in human jawbone surrounding a dental implant. Based on some popular yet distinctive theories for bone remodelling, a new algorithm is proposed that takes into account both the ??lazy zone?? effect and the self-organizational control process. The proposed algorithm is first verified by a two-dimensional (2D) plate model simulating bone tissue, then, a 2D finite element model of implant and jawbone is studied. The effects of two parameters, viz the reference value of strain energy density (SED) and the ??lazy zone?? region, on density distribution are also investigated. The proposed algorithm is proven to be effective, and the predicted density distribution patterns correlate well with clinical observations. This study has demonstrated that consideration of the lazy zone is less important than consideration of the stress and strain (quantified as SED) induced within the bone.  相似文献   
36.
Abstract— The exciton decay time in organic light‐emitting devices (OLEDs) depends on the optical environment, i.e., the thicknesses and refractive indices of all layers in a device. The decay of an exciton can occur through a radiative or a non‐radiative channel. Each of these channels has a probability, which is expressed by, respectively, the radiative and the non‐radiative decay rate. The radiative decay rate is influenced by the optical environment, i.e., the OLED's thin‐film layer structure. In this paper, a model for estimating the change of the exciton decay time (inverse of the decay rate) is presented. In addition, the decay time change in both top‐ and bottom‐emitting OLEDs as a function of the charge‐transport layer thicknesses has been investigated. Furthermore, the most important mechanism responsible for the exciton decay time change is outlined.  相似文献   
37.
Cancer is a major cause of death, affecting human life in both developed and developing countries. Numerous antitumor agents exist but their toxicity and low efficacy limits their utility. Furthermore, the complex pathophysiological mechanisms of cancer, serious side effects and poor prognosis restrict the administration of available cancer therapies. Thus, developing novel therapeutic agents are required towards a simultaneous targeting of major dysregulated signaling mediators in cancer etiology, while possessing lower side effects. In this line, the plant kingdom is introduced as a rich source of active phytochemicals. The secondary metabolites produced by plants could potentially regulate several dysregulated pathways in cancer. Among the secondary metabolites, flavonoids are hopeful phytochemicals with established biological activities and minimal side effects. Flavonoids inhibit B-cell lymphoma 2 (Bcl-2) via the p53 signaling pathway, which is a significant apoptotic target in many cancer types, hence suppressing a major dysregulated pathway in cancer. To date, there have been no studies reported which extensively highlight the role of flavonoids and especially the different classes of flavonoids in the modulation of Bcl-2 in the P53 signaling pathway. Herein, we discuss the modulation of Bcl-2 in the p53 signaling pathway by different classes of flavonoids and highlight different mechanisms through which this modulation can occur. This study will provide a rationale for the use of flavonoids against different cancers paving a new mechanistic-based approach to cancer therapy.  相似文献   
38.
In this contribution, four new compounds synthesized from 4-hydroxycoumarin and tyramine/octopamine/norepinephrine/3-methoxytyramine are characterized spectroscopically (IR and NMR), chromatographically (UHPLC-DAD), and structurally at the B3LYP/6-311++G*(d,p) level of theory. The crystal structure of the 4-hydroxycoumarin-octopamine derivative was solved and used as a starting geometry for structural optimization. Along with the previously obtained 4-hydroxycoumarin-dopamine derivative, the intramolecular interactions governing the stability of these compounds were quantified by NBO and QTAIM analyses. Condensed Fukui functions and the HOMO-LUMO gap were calculated and correlated with the number and position of OH groups in the structures. In vitro cytotoxicity experiments were performed to elucidate the possible antitumor activity of the tested substances. For this purpose, four cell lines were selected, namely human colon cancer (HCT-116), human adenocarcinoma (HeLa), human breast cancer (MDA-MB-231), and healthy human lung fibroblast (MRC-5) lines. A significant selectivity towards colorectal carcinoma cells was observed. Molecular docking and molecular dynamics studies with carbonic anhydrase, a prognostic factor in several cancers, complemented the experimental results. The calculated MD binding energies coincided well with the experimental activity, and indicated 4-hydroxycoumarin-dopamine and 4-hydroxycoumarin-3-methoxytyramine as the most active compounds. The ecotoxicology assessment proved that the obtained compounds have a low impact on the daphnia, fish, and green algae population.  相似文献   
39.
This paper presents a new technique for tracking-error model-based Parallel Distributed Compensation (PDC) control for non-holonomic vehicles where the outputs (measurements) of the system are delayed and the delay is constant. Briefly, this technique consists of rewriting the kinematic error model of the mobile robot tracking problem into a TS fuzzy representation and finding a stabilizing controller by solving LMI conditions for the tracking-error model. The state variables are estimated by nonlinear predictor observer where the outputs are delayed by a constant delay. To illustrate the efficiency of the proposed approach a comparison between the TS fuzzy observer and the nonlinear predictor observer is shown. For this study the reference trajectory is built by taking into account the acceleration limits of the mobile robot. All experiments are implemented on simulation and the real-time platform.  相似文献   
40.
Task-oriented repetitive movements can improve motor performance in patients with neurological or orthopaedic lesions. The application of robotics and automation technology can serve to assist, enhance, evaluate, and document neurological and orthopedic rehabilitation. This paper deals with the application of "patient-cooperative" techniques to robot-aided gait rehabilitation of neurological disorders. We define patient-cooperative to mean that, during movement, the technical system takes into account the patient's intention and voluntary efforts rather than imposing any predefined movements or inflexible strategies. It is hypothesized that such cooperative robotic approaches can improve the therapeutic outcome compared to classical rehabilitation strategies. New cooperative strategies are presented that detect the patient's voluntary efforts. First, this enables the patient increased freedom of movement by a certain amount of robot compliance. Second, the robot behavior adapts to the existing voluntary motor abilities. And third, the robotic system displays and improves the patient contribution by visual biofeedback. Initial experimental results are presented to evaluate the basic principle and technical function of proposed approaches. Further improvements of the technical design and additional clinical testing is required to prove whether the therapeutic outcome can be enhanced by such cooperative strategies.  相似文献   
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