933 resultados para advanced solid tumors
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In this paper, a hybrid smoothed finite element method (H-SFEM) is developed for solid mechanics problems by combining techniques of finite element method (FEM) and Node-based smoothed finite element method (NS-FEM) using a triangular mesh. A parameter is equipped into H-SFEM, and the strain field is further assumed to be the weighted average between compatible stains from FEM and smoothed strains from NS-FEM. We prove theoretically that the strain energy obtained from the H-SFEM solution lies in between those from the compatible FEM solution and the NS-FEM solution, which guarantees the convergence of H-SFEM. Intensive numerical studies are conducted to verify these theoretical results and show that (1) the upper and lower bound solutions can always be obtained by adjusting ; (2) there exists a preferable at which the H-SFEM can produce the ultrasonic accurate solution.
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Advances in solid-state switches and power electronics techniques have led to the development of compact, efficient and more reliable pulsed power systems. This paper proposes an efficient scheme that utilizes modular switch-capacitor units in obtaining high voltage levels with fast rise time (dv/dt) using low voltage solid-state switches. The proposed pulsed power supply has flexibility in terms of controlling energy and generating broad range of voltage levels. The energy flow can be controlled as the stored energy can be adjusted by a current source utilized at the first stage of the system. Desirable voltage level can be obtained by connecting adequate number of switch-capacitor units. Moreover, the proposed topology is load independent. Therefore it can easily supply wide range of applications especially the low impedance ones. The effectiveness of the proposed approach is verified by simulations
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Aim his study reports the use of exploratory factor analysis to determine construct validity of a modified advanced practice role delineation tool. Background Little research exists on specific activities and domains of practice within advanced practice nursing roles, making it difficult to define service parameters of this level of nursing practice. A valid and reliable tool would assist those responsible for employing or deploying advanced practice nurses by identifying and defining their service profile. This is the third paper from a multi-phase Australian study aimed at assigning advanced practice roles. Methods A postal survey was conducted of a random sample of state government employed Registered nurses and midwives, across various levels and grades of practice in the state of Queensland, Australia, using the modified Advanced Practice Role Delineation tool. Exploratory factor analysis, using principal axis factoring was undertaken to examine factors in the modified tool. Cronbach’s alpha coefficient determined reliability of the overall scale and identified factors. Results There were 658 responses (42% response rate). The five factors found with loadings of ≥.400 for 40 of the 41 APN activities were similar to the five domains in the Strong model. Cronbach’s alpha coefficient was .94 overall and for the factors ranged from 0.83 to 0.95. Conclusion Exploratory factor analysis of the modified tool supports validity of the five domains of the original tool. Further investigation will identify use of the tool in a broader healthcare environment.
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This paper investigates advanced channel compensation techniques for the purpose of improving i-vector speaker verification performance in the presence of high intersession variability using the NIST 2008 and 2010 SRE corpora. The performance of four channel compensation techniques: (a) weighted maximum margin criterion (WMMC), (b) source-normalized WMMC (SN-WMMC), (c) weighted linear discriminant analysis (WLDA), and; (d) source-normalized WLDA (SN-WLDA) have been investigated. We show that, by extracting the discriminatory information between pairs of speakers as well as capturing the source variation information in the development i-vector space, the SN-WLDA based cosine similarity scoring (CSS) i-vector system is shown to provide over 20% improvement in EER for NIST 2008 interview and microphone verification and over 10% improvement in EER for NIST 2008 telephone verification, when compared to SN-LDA based CSS i-vector system. Further, score-level fusion techniques are analyzed to combine the best channel compensation approaches, to provide over 8% improvement in DCF over the best single approach, (SN-WLDA), for NIST 2008 interview/ telephone enrolment-verification condition. Finally, we demonstrate that the improvements found in the context of CSS also generalize to state-of-the-art GPLDA with up to 14% relative improvement in EER for NIST SRE 2010 interview and microphone verification and over 7% relative improvement in EER for NIST SRE 2010 telephone verification.
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Bioceramics play an important role in repairing and regenerating bone defects. Annually, more than 500,000 bone graft procedures are performed in the United states and approximately 2.2 million are conducted worldwide. The estimated cost of these procedures approaches $2.5billion per year. Around 60% of the bone graft substitutes available on the market involve bioceramics. It is reported that bioceramics in the world market increase by 9% per year. For this reason, the research of bioceramics has been one of the most active areas during, the past several years. Considering the significant importance of bioceramics, our goal was to compile this book to review the latest research advances in the field of bioceramics. The text also summarizes our work during the past 10 years in an effort to share innovative concepts, design of bioceramisc, and methods for material synthesis and drug delivery. We anticipate that this text will provide some useful information and guidance in the bioceramics field for biomedical engineering researchers and material scientists. Information on novel mesoporous bioactive glasses and silicate-based ceramics for bone regeneration and drug delivery are presented. Mesoporous bioactive glasses have shown multifunctional characteristics of bone regeneration and drug delivery due to their special mesopore structures,whereas silicated-based bioceramics, as typical third-generation biomaterials,possess significant osteostimulation properties. Silica nanospheres with a core-shell structure and specific properties for controllable drug delivery have been carefully reviewed-a variety of advanced synthetic strategies have been developed to construct functional mesoporous silica nanoparticles with a core-shell structure, including hollow, magnetic, or luminescent, and other multifunctional core-shell mesoporous silica nanoparticles. In addition, multifunctional drug delivery systems based on these nanoparticles have been designed and optimized to deliver the drugs into the targeted organs or cells,with a controllable release fashioned by virtue of various internal and external triggers. The novel 3D-printing technique to prepare advanced bioceramic scaffolds for bone tissue engineering applications has been highlighted, including the preparation, mechanical strength, and biological properties of 3D-printed porous scaffolds of calcium phosphate cement and silicate bioceramics. Three-dimensional printing techniques offer improved large-pore structure and mechanical strength. In addition , biomimetic preparation and controllable crystal growth as well as biomineralization of bioceramics are summarized, showing the latest research progress in this area. Finally, inorganic and organic composite materials are reviewed for bone regeneration and gene delivery. Bioactive inorganic and organic composite materials offer unique biological, electrical, and mechanical properties for designing excellent bone regeneration or gene delivery systems. It is our sincere hope that this book will updated the reader as to the research progress of bioceramics and their applications in bone repair and regeneration. It will be the best reward to all the contributors of this book if their efforts herein in some way help reader in any part of their study, research, and career development.
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Selective separation of nitrogen (N2) from methane (CH4) is highly significant in natural gas purification, and it is very challenging to achieve this because of their nearly identical size (the molecular diameters of N2 and CH4 are 3.64 Å and 3.80 Å, respectively). Here we theoretically study the adsorption of N2 and CH4 on B12 cluster and solid boron surfaces a-B12 and c-B28. Our results show that these electron-deficiency boron materials have higher selectivity in adsorbing and capturing N2 than CH4, which provides very useful information for experimentally exploiting boron materials for natural gas purification.
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Obesity and type 2 diabetes are recognised risk factors for the development of some cancers and, increasingly, predict more aggressive disease, treatment failure, and cancer-specific mortality. Many factors may contribute to this clinical observation. Hyperinsulinaemia, dyslipidaemia, hypoxia, ER stress, and inflammation associated with expanded adipose tissue are thought to be among the main culprits driving malignant growth and cancer advancement. This observation has led to the proposal of the potential utility of “old players” for the treatment of type 2 diabetes and metabolic syndrome as new cancer adjuvant therapeutics. Androgen-regulated pathways drive proliferation, differentiation, and survival of benign and malignant prostate tissue. Androgen deprivation therapy (ADT) exploits this dependence to systemically treat advanced prostate cancer resulting in anticancer response and improvement of cancer symptoms. However, the initial therapeutic response from ADT eventually progresses to castrate resistant prostate cancer (CRPC) which is currently incurable. ADT rapidly induces hyperinsulinaemia which is associated with more rapid treatment failure. We discuss current observations of cancer in the context of obesity, diabetes, and insulin-lowering medication. We provide an update on current treatments for advanced prostate cancer and discuss whether metabolic dysfunction, developed during ADT, provides a unique therapeutic window for rapid translation of insulin-sensitising medication as combination therapy with antiandrogen targeting agents for the management of advanced prostate cancer.
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The optimisation study of the fabrication of a compact TiO2 blocking layer (via Spray Pyrolysis Deposition) for poly (3-hexylthiopene) (P3HT) for Solid State Dye Sensitized Solar Cells (SDSCs) is reported. We used a novel spray TiO2 precursor solution composition obtained by adding acetylacetone to a conventional formulation (Diisopropoxytitanium bis (acetylacetonate) in ethanol). By Scanning Electron Microscopy a TiO2 layer with compact morphology and thickness of around 100 nmis shown. Through a Tafel plot analysis an enhancement of the device diode-like behaviour induced by the acetylacetone blocking layer respect to the conventional one is observed. Significantly, the device fabricatedwith the acetylacetone blocking layer shows an overall increment of the cell performance with respect to the cellwith the conventional one (DJsc/Jsc = +13.8%, DFF/FF = +39.7%, DPCE/PCE = +55.6%). A conversion efficiency optimumis found for 15 successive spray cycles where the diode-like behaviour of the acetylacetone blocking layer is more effective. Over three batches of cells (fabricated with P3HT and dye D35) an average conversion efficiency value of 3.9% (under a class A sun simulator with 1 sun A.M. 1.5 illumination conditions) was measured. From the best cell we fabricated a conversion efficiency value of 4.5% was extracted. This represents a significant increment with respect to previously reported values for P3HT/dye D35 based SDSCs.
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Background: Fatigue is a distressing symptom experienced by approximately 74-88% of patients with advanced cancer. Although there have been advances in managing fatigue with the use of a range of pharmacologic and non-pharmacologic strategies, fatigue is not well-managed in patients with advanced cancer. Objectives: For patients with advanced cancer, the aims of the study were to examine the self-management (SM) behaviours associated with fatigue; the perceived effectiveness of these SM behaviours, and the socio-demographic and clinical factors influencing the effectiveness of these SM behaviours. Methodology: A prospective longitudinal study was undertaken with 152 patients with metastatic breast, lung, colorectal and prostate cancer experiencing fatigue (>3/10) over a two month period. SM behaviours associated with fatigue, medical/demographic characteristics, social support, depression, anxiety, self-efficacy and other symptoms were assessed. Results: Findings indicate that on most fatigue severity measures, levels of fatigue increased slightly over time. On average, participants used nine fatigue SM behaviours at each time point. Participants reported that the most effective SM behaviours were ‘pacing their activities during the day’, ‘planning activities to make the most of energy’, ‘taking short sleeps’, ‘doing things that distract them from their fatigue’, and ‘doing things to improve sleep at night’. Factors associated with the increased effectiveness of fatigue SM behaviours included higher self-efficacy, higher education level, lower levels of depressive symptoms, and lower functional status. These results can be used to inform the design of future interventions to support the use of effective fatigue SM behaviours in this population.
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Locally available different bbiomass solid wastes, pine seed, date seed, plum seed, nutshell, hay of catkin, rice husk, jute stick, saw-dust, wheat straw and linseed residue in the particle form have been pyrolyzed in laboratory scale fixed bed reactor. The products obtained are pyrolysis oil, solid char and gas. The oil and char are collected while the gas is flared into atmosphere. The variation of oil yield for different biomass feedstock with reaction parameters like, reactor bed temperature, feed size and running time is presented in a comparative way in the paper. A maximum liquid yield of 55 wt% of dry feedstock is obtained at an optimum temperature of 500 °C for a feed size of 300-600 μm with a running time of 55 min with nutshell as the feedstock while the minimum liquid yield is found to be 30 wt% of feedstock at an optimum temperature of 400 °C for a feed size of 2.36 mm with a running time of 65 min for linseed residue. A detailed study on the variation of product yields with reaction parameters is presented for the latest investigation with pine seed as the feedstock where a maximum liquid yield of 40 wt% of dry feedstock is obtained at an optimum temperature of 500 °C for a feed size of 2.36-2.76 mm with a running time of 120 min. The characterization of the pyrolysis oil is carried out and a comparison of some selected properties of the oil is presented. From the study it is exhibited that the biomass solid wastes have the potential to be converted into liquid oil as a source of renewable energy with some further upgrading of the products.
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TO THE EDITOR: It was with great interest that I read two recent articles by de Raaf et al1, and Bruera et al2. These authors are to be congratulated for completing two of the very few high quality randomized trials that evaluate complex interventions for managing fatigue in patients with advanced cancer. de Raaf et al conducted a non-blinded RCT with 152 patients with advanced cancer and reported significant reduction of fatigue in patients who received a nurse-led monitoring and protocol-guided treatment of physical symptoms compared with those who received usual care1. Patients who received this intervention experienced a significant improvement over time in general fatigue, at one-month follow-up and two-month follow-up. Another recent RCT conducted with 141 patients with advanced cancer by Bruera et al2 did not find any benefits of a nursing telephone intervention that involved systematic symptom assessment/management, medication review, psychosocial support and patient education in fatigue reduction, compared to those who received a control telephone intervention conducted by a non-professional...
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High-performance liquid chromatography coupled with solid phase extraction method was developed for determination of isofraxidin in rat plasma after oral administration of Acanthopanax senticosus extract (ASE), and pharmacokinetic parameters of isofraxidin either in ASE or pure compound were measured. The HPLC analysis was performed on a Dikma Diamonsil RP(18) column (4.6 mm x 150 mm, 5 microm) with the isocratic elution of solvent A (acetonitrile) and solvent B (0.1% aqueous phosphoric acid, v/v) (A : B = 22 : 78) and the detection wavelength was set at 343 nm. The calibration curve was linear over the range of 0.156-15.625 microg/ml. The limit of detection was 60 ng/ml. The intra-day precision was 5.8%, and the inter-day precision was 6.0%. The recovery was 87.30+/-1.73%. When the dosage of ASE is equal to pure compound caculated by the amount of isofraxidin, it has been found to have two maximum concentrations in plasma while the pure compound only showed one peak in the plasma concentration-time curve. The determined content of isofraxidin in plasma after oral administration of ASE is the total contents of free isofraxidin and its precursors in ASE in vitro. The pharmacokinetic characteristics of ASE showed the priority of the extract and the properities of traditional Chinese medicine.
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High performance liquid chromatography (HPLC) coupled with the solid phase extraction method was developed for determining cimifugin (a coumarin derivative; one of Saposhnikovia divaricatae's constituents) in rat plasma after oral administration of Saposhnikovia divaricatae extract (SDE), and the pharmacokinetics of cimifugin either in SDE or as a single compound was investigated. The HPLC analysis was performed on a commercially available column (4.6 mm x 200 mm, 5 pm) with the isocratic elution of solvent A (Methanol) and solvent B (Water) (A:B=60:40) and the detection wavelength was set at 250 nm. The calibration curve was linear over the range of 0.100-10.040 microg/mL. The limit of detection was 30 ng/mL. At the rat plasma concentrations of 0.402, 4.016, 10.040 microg/mL, the intra-day precision was 6.21%, 3.98%, and 2.23%; the inter-day precision was 7.59%, 4.26%, and 2.09%, respectively. The absolute recovery was 76.58%, 76.61%, and 77.67%, respectively. When the dosage of SDE was equal to the pure compound calculated by the amount of cimifugin, it was found to have two maximum peaks while the pure compound only showed one peak in the plasma concentration-time curve. The pharmacokinetic characteristics of SDE showed the superiority of the extract and the properties of traditional Chinese medicine.
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Skin tumors can arise as a result of cumulative genetic abnormalities, including chromosomal aberrations that can be described as either morphological (structural rearrangements) or molecular (copy number variations). Cytogenetic techniques have been used to examine both large and small chromosomal aberrations, and include karyotyping, comparative genomic hybridization, and fluorescence in situ hybridization. This chapter describes the recurrent aberrations associated with skin tumors, such as benign melanocytic nevi, melanoma, basal cell carcinoma, squamous cell carcinoma, actinic (solar) keratosis, Bowen’s disease, keratoacanthoma, Merkel cell carcinoma, dermatofibrosarcoma protuberans, and cutaneous lymphomas, as detected by cytogenetic methodologies. A significant number of genomic aberrations are shared across different subtypes of skin tumors, including structural and numerical alterations of chromosome 1, −3p, +3q, +6, +7, +8q, −9p, +9q, −10, −17p, +17q and +20. Aberrations specific to certain skin cancers have also been detected, and include: loss of 18q in squamous cell carcinoma, but not its precursor, actinic keratosis; loss of 9q22 in sporadic basal cell carcinoma; and translocation involving 17q22 and 22q13 in dermatofibrosarcoma protuberans. These regions contain a number of potential candidate genes that are involved in aspects of cell signaling, proliferation, differentiation, and apoptosis. Cytogenetic methodologies continue to evolve with the advent of array-based comparative genomic hybridization, copy number variation microarrays, and next-generation sequencing. It is envisioned that cytogenetic analysis will continue to be employed for identification and further exploration of novel chromosomal regions and associated genes that drive skin tumorigenesis.
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Effective management of chronic diseases is a global health priority. A healthcare information system offers opportunities to address challenges of chronic disease management. However, the requirements of health information systems are often not well understood. The accuracy of requirements has a direct impact on the successful design and implementation of a health information system. Our research describes methods used to understand the requirements of health information systems for advanced prostate cancer management. The research conducted a survey to identify heterogeneous sources of clinical records. Our research showed that the General Practitioner was the common source of patient's clinical records (41%) followed by the Urologist (14%) and other clinicians (14%). Our research describes a method to identify diverse data sources and proposes a novel patient journey browser prototype that integrates disparate data sources.