bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated Tribo-Chemical Modeling of Copper CMP
Authors: Tripathi Shantanu , Choi Seungchoun , Doyle Fiona M. , Dornfeld David A.
Published: March 2010

Copper CMP is a corrosion-wear process, in which mechanical and chemical-electrochemical phenomena interact synergistically. Existing models generally treat copper CMP as a corrosion enhanced wear process. However, the underlying mechanisms suggest that copper CMP would be better modeled as a wear enhanced corrosion process, where intermittent asperity/abrasive action enhances the local oxidation rate, and is followed by time-dependent passivation of copper. In this work an integrated tribo-chemical model of material removal at the asperity/abrasive scale was developed. Abrasive and pad properties, process parameters, and slurry chemistry are all considered. Three important components of this model are the passivation kinetics of copper in CMP slurry chemicals; the mechanical response of protective films on copper; and the interaction frequency of copper with abrasives/pad asperities. The material removal rate during copper CMP was simulated using the tribo-chemical model, using input parameters obtained experimentally in accompanying research or from the literature.
Platelet Rich Plasma to Facilitate Wound Healing Following Tooth Extraction
Authors: Rutkowski James L. , Johnson David A. , Radio Nicholas M. , Fennell James W.
Published: March 2010

Following tooth removal bone formation normally takes 16 weeks and may result in less than adequate volume for the necessary reconstruction. Platelet rich plasma (PRP) has been promoted as an effective method for improving bone formation. Its use is often expensive, time consuming, or not clinically convenient for the patient and/or clinician. This study examines a simple method for obtaining a “Buffy Coat”-PRP (BC-PRP) and its effect on bone healing following the removal of bilateral mandibular 3rd molars. Subtraction digital radiography and CT scan analysis were used to track changes in radiographic density at PRP treated sites in comparison to ipsilateral non-PRP treated sites. PRP treated sites demonstrated early and significant increased radiographic density over baseline measurements following tooth removal. The greatest benefit of PRP is during the initial 2-week postoperative healing time period (P < .001). During weeks 3 though 12, BC-PRP treatment resulted in significant (P < .0001) increases in bone density compared to control, but there was no significant interaction between time and treatment (P > .05). For the entire time period (0–25 weeks) PRP treatment was significant (P < .0001) and time was significant (P < .0001) but there was no significant interaction (P > .05) between the effect of PRP treatment and time. It required 6 weeks for control extraction sites to reach comparable bone density that PRP treated sites achieved at week 1. Postoperative pain, bleeding, and numbness were not significantly affected by BC-PRP application. Results suggest that this simple technique may be of value to clinicians performing oral surgery by facilitating bone regeneration following tooth extraction.
Computer-Assisted Surgery in the Lower Jaw: Double Surgical Guide for Immediately Loaded Implants in Postextractive Sites—Technical Notes and a Case Report
Authors: De Santis Daniele , Canton Luciano Claudio , Cucchi Alessandro , Zanotti Guglielmo , Pistoia Enrico , Nocini Pier Francesco
Published: March 2010

Computer-assisted surgery is based on computerized tomography (CT) scan technology to plan the placement of dental implants and a computer-aided design/computer-aided manufacturing (CAD-CAM) technology to create a custom surgical template. It provides guidance for insertion implants after analysis of existing alveolar bone and planning of implant position, which can be immediately loaded, therefore achieving esthetic and functional results in a surgical stage. The absence of guidelines to treat dentulous areas is often due to a lack of computer-assisted surgery. The authors have attempted to use this surgical methodology to replace residual teeth with an immediate implantoprosthetic restoration. The aim of this case report is to show the possibility of treating a dentulous patient by applying a computer-assisted surgical protocol associated with the use of a double surgical template: one before extraction and a second one after extraction of selected teeth.
Treatment of a Maxillary Dento-Alveolar Defect Using an Immediately Loaded Definitive Zygoma Implant-Retained Prosthesis With 11-Month Follow-Up: A Clinical Report
Authors: Baig Mirza Rustum , Rajan Gunaseelan
Published: March 2010

This article describes the dental implant-based rehabilitation of a partially edentulous patient with a unilateral maxillary dento-alveolar defect. A screw-retained prosthesis with a modified design was fabricated on zygomatic and regular dental implants. One section of the implant prosthesis has cemented crowns and the other section is conventional screw-retained. The design of the prosthesis overcame the hard and soft tissue deficit and provided the desired esthetics.
Periosteal Releasing Incision for Successful Coverage of Augmented Sites. A Technical Note
Authors: Romanos George E.
Published: March 2010

The periosteal releasing incision (PRI) is very common in intraoral surgical procedures, especially when flap advancement is indicated, that is, when vertical or horizontal augmentations take place. This technical note describes the surgical skills for sufficient flap advancement. Complications due to improper PRI are also discussed.
Everolimus (RAD001) in the Treatment of Advanced Renal Cell Carcinoma: A Review
Authors: Agarwala Sanjiv S. , Case Scott
Published: March 2010

Historically, there have been few treatment options for patients with advanced renal cell carcinoma (RCC) besides immunotherapy with interleukin-2 and interferon (IFN)-α. Targeted therapies have improved clinical outcomes over the past several years. These include the vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors sunitinib and sorafenib, which inhibit angiogenic signaling in endothelial cells and vascular pericytes predominantly through VEGFR and platelet-derived growth factor receptor β. Also included is the anti-VEGF monoclonal antibody bevacizumab used in combination with IFN-α. These agents mediate their antitumor effects by interfering with the VEGF signaling pathway, thereby inhibiting angiogenesis and causing tumor shrinkage. However, ultimately, most patients develop resistance and experience disease progression during VEGF/VEGFR-targeted therapy, and until the recent approval of the mammalian target of rapamycin (mTOR) inhibitor everolimus (RAD001), there were no agents available with proven activity in this setting. This review describes the clinical development of everolimus in advanced RCC and the rationale for the use of mTOR inhibitors after failure of VEGF/VEGFR inhibitors.
Performance estimation of prestressed concrete box girders
Authors: Madhavi T. Ch. , Sekar M. , Paramasivam V.
Published: March 2010

A composite layered approach is adopted in this paper for the analysis of prestressed concrete box girders, which have complex behaviour. The multilayer shell element is made up of many layers with different thickness, and different material models are assigned to various layers so that the structural performance can be directly connected with the material constitutive law. In the present work, the load history is divided into a sequence of steps and the step-by-step procedure is used for different loading stages. Experimental investigations are conducted and the results are compared with the analytical values. The study reveals the potential of numerical simulation developed for box girders using a layered approach to predict the behaviour of the members when the prestressing force and external loads are applied.akes it available for a much wider audience. The software has been used with great success in teaching as well as in conceptual design environments such as architecture, industrial design and engineering. The addition of an optimisation algorithm and tablet PC support makes the software even more interesting as a tool for conceptual design.
Ranking water transfer projects using fuzzy methods
Authors: Razavi Toosi S. L. , Samani J. M. V. , Koorehpazan Dezfuli A.
Published: March 2010

Water scarcity is an important problem in water resources. There is not enough financial capability to execute all water resources projects at one time; therefore it is important to rank execution projects. One of the vital issues in water resource management is project ranking. The objective of this paper is to employ different fuzzy multiple attribute group decision-making methods for ranking some of the inter-basin water transfer projects of the Karun river. The methods were: maximising and minimising sets method; the Bonissone's method for group decision making; fuzzy Topsis for group decision making; and fuzzy decision-making software. A set of ten inter-basin water transfer projects with eight criteria were considered. The weights of criteria were determined by five water resources experts, then based on the selected criteria, the rating preference for each alternative was obtained by the experts. Finally, the results of different methods were compared. The final ranking results were comparable with each other. The Spearman rank correlation coefficient was employed to assess the correlation coefficient between the ranking results obtained by the above multiple attribute decision-making methods. Also, sensitivity analysis on different selected criteria weights was conducted.
Periodontal‐Endodontic Lesion of a Three‐Rooted Maxillary Premolar: Report of a Case
Authors: Blanchard Steven B. , Almasri Amjad , Gray Jonathon L.
Published: March 2010

Background: A 43‐year‐old African American male initially presented for a dental evaluation of a recurrent swelling on the buccal aspect of tooth #12. His medical history was unremarkable except for a 20–pack year history of smoking. He was eventually diagnosed as having a necrotic pulp #12, and received root canal treatment. The patient's problem was unresolved, and he was subsequently referred for a periodontal evaluation with a presumptive diagnosis of a periodontal abscess.

Methods: A flap was reflected from teeth #11 through #15. A buccal furcation invasion was discovered on #12. Shortly thereafter, three distinct roots with three grade III furcation invasions were located. The tooth was deemed untreatable, and was extracted. The thin buccal plate of the extraction socket was preserved using freeze‐dried bone allograft to facilitate future prosthodontic replacement.

Results: Healing was uneventful. Periodontal open flap debridement surgery was provided for the remainder of the mouth, and the patient was placed on a 3‐month recall program.

Conclusions: Periodontitis associated with endodontic lesions are among the most daunting diagnostic and therapeutic challenges faced by periodontists. This is particularly true for maxillary premolars with multiple roots. The tooth in this case, once periodontally involved, had a very poor prognosis. The prognosis was further compromised by the pulpal involvement. Therapy consisted of extraction of the tooth to relieve the patient's discomfort and treating the adjacent teeth with periodontal open flap debridement surgery. A review of the literature pertinent to the diagnosis and management of periodontal‐endodontic lesions is also presented.
Preparation of xanthated bentonite and its removal behavior for Pb(II) ions
Authors: He Y. F. , Li F. R. , Wang R. M. , Li F. Y. , Wang Y. , Zhang Z. H.
Published: March 2010

Xanthate was successfully grafted onto bentonite by a relatively simple solution reaction. The obtained xanthated bentonite (XBent) was characterized by FT-IR spectrophotometer, thermogravimetric analysis (TG), particle size analysis, x-ray diffraction (XRD) and scanning electron microscopy (SEM). XBent acting as a type of environmentally friendly adsorbent was applied to remove lead ions from aqueous solutions. The optimum conditions were as follows: [Pb2 + ] = 500 mg L−1, [XBent] = 2 g L−1, pH = 5.0; oscillating 60 min under 200 rpm at 25°C. The removal rate of lead was up to 99.9%. It was found that the lead(II) ions—XBent adsorption isotherm model fitted well to the Freundlich isotherm. The adsorption mechanism was also investigated by SEM and XRD, which concluded that lead ions were complexed or chelated with XBent. XBent appears to have potential to be used later in water treatment as a type of inorganic polymer reagent.
Application of the central composite design for condition optimization for semi-aerobic landfill leachate treatment using electrochemical oxidation
Authors: Mohajeri Soraya , Aziz Hamidi Abdul , Isa Mohamed Hasnain , Zahed Mohammad Ali , Bashir Mohammed J. K. , Adlan Mohd. Nordin
Published: March 2010

In the present study, Electrochemical Oxidation was used to remove COD and color from semi-aerobic landfill leachate collected from Pulau Burung Landfill Site (PBLS), Penang, Malaysia. Experiments were conducted in a batch laboratory-scale system in the presence of NaCl as electrolyte and aluminum electrodes. Central composite design (CCD) under Response surface methodology (RSM) was applied to optimize the electrochemical oxidation process conditions using chemical oxygen demand (COD) and color removals as responses, and the electrolyte concentrations, current density and reaction time as control factors. Analysis of variance (ANOVA) showed good coefficient of determination (R2) values of >0.98, thus ensuring satisfactory fitting of the second-order regression model with the experimental data. In un-optimized condition, maximum removals for COD (48.77%) and color (58.21%) were achieved at current density 80 mA/cm2, electrolyte concentration 3,000 mg/L and reaction time 240 min. While after optimization at current density 75 mA/cm2, electrolyte concentration 2,000 mg/L and reaction time 218 min a maximum of 49.33 and 59.24% removals were observed for COD and color respectively.
Improvement of olfactometric measurement accuracy and repeatability by optimization of panel selection procedures
Authors: Capelli L. , Sironi S. , Del Rosso R. , Céntola P. , Bonati S.
Published: March 2010

The EN 13725:2003, which standardizes the determination of odour concentration by dynamic olfactometry, fixes the limits for panel selection in terms of individual threshold towards a reference gas (n-butanol in nitrogen) and of standard deviation of the responses. Nonetheless, laboratories have some degrees of freedom in developing their own procedures for panel selection and evaluation. Most Italian olfactometric laboratories use a similar procedure for panel selection, based on the repeated analysis of samples of n-butanol at a concentration of 60 ppm. The first part of this study demonstrates that this procedure may originate a sort of “smartening” of the assessors, which means that they become able to guess the right answers in order to maintain their qualification as panel members, independently from their real olfactory perception. For this reason, the panel selection procedure has been revised with the aim of making it less repetitive, therefore preventing the possibility for panel members to be able to guess the best answers in order to comply with the selection criteria. The selection of new panel members and the screening of the active ones according to this revised procedure proved this new procedure to be more selective than the “standard” one. Finally, the results of the tests with n-butanol conducted after the introduction of the revised procedure for panel selection and regular verification showed an effective improvement of the laboratory measurement performances in terms of accuracy and precision.
A pathway to a more sustainable water sector: sustainability-based asset management
Authors: Marlow D. R. , Beale D. J. , Burn S.
Published: March 2010

The water sectors of many countries are faced with the need to address simultaneously two overarching challenges; the need to undertake effective asset management coupled with the broader need to evolve business processes so as to embrace sustainability principles. Research has thus been undertaken into the role sustainability principles play in asset management. As part of this research, a series of 25 in-depth interviews were undertaken with water sector professionals from around Australia. Drawing on the results of these interviews, this paper outlines the conceptual relationship between asset management and sustainability along with a synthesis of the relevant opinions voiced in the interviews. The interviews indicated that the participating water authorities have made a strong commitment to sustainability, but there is a need to facilitate change processes to embed sustainability principles into business as usual practices. Interviewees also noted that asset management and sustainability are interlinked from a number of perspectives, especially in the way decision making is undertaken with respect to assets and service provision. The interviews also provided insights into the research needed to develop a holistic sustainability-based asset management framework.
Faecal sterols analysis for the identification of human faecal pollution in a non-sewered catchment
Authors: Sullivan D. , Brooks P. , Tindale N. , Chapman S. , Ahmed W.
Published: March 2010

In this study, faecal sterols were used to identify human faecal pollution in a non-sewered catchment in Southeast Queensland, Australia. In all, 36 water samples were collected from six sites on six occasions and the concentration of sterols were determined using gas chromatography and mass spectrometry. The stanols concentration in water samples generally increased with increased catchment runoff. After moderate rainfall, high coprostanols levels found in water samples indicated human faecal pollution via defective septic systems. In contrast, it appears that during dry weather human faecal pollution is not occurring in the study catchment. Sterol profiles also pointed to a cattle farm polluting during modest catchment runoff. The method used in this study was able to identify the sources of faecal pollution to the catchment due to rainfall.
Innovative approach to centrate nitrification accomplishes multiple goals: nitrogen removal and odour control
Authors: Husband Joseph A. , Phillips Jennifer , Coughenour J. R. , Walz Thomas , Blatchford Gary
Published: March 2010

In 2001, the City of Phoenix, Arizona (USA) committed to the conversion of the existing high-rate anaerobic digestion process at the 8.9 m3/s 91st Avenue Wastewater Treatment Plant (WWTP) to a multi-phase process (acid/methane, mesophilic/thermophilic) to optimise existing digestion capacity and achieve Class A biosolids. The improved solids reduction is anticipated to double the ammonia load in the sludge dewatering liquor (centrate), which is currently treated in the nitrification/denitrification (NdeN) activated sludge facilities. In order to continue to meet the plant total nitrogen discharge limit of 10 mg/L as N, a separate centrate nitrification system was incorporated into the plant's process flow scheme to efficiently manage the high ammonia recycle stream. By discharging the nitrified centrate to the plant headworks, an added benefit of reduced hydrogen sulfide (H2S) emissions was realised to approximately $310 (USD).
Improving the capacitive deionisation performance by optimising pore structures of the electrodes
Authors: Zou L. , Li L. , Song H. , Morris G.
Published: March 2010

In this paper, three types of ordered mesoporous carbons (OMCs) were synthesised by an original template method and a modified sol-gel process involving nickel salts. The effects of pore arrangement pattern (ordered and random), and pore size distribution (mesoporous and microporous) on the desalination performance were investigated by comparing mesoporous carbons with activated carbons (ACs). It is found that the mesoporous carbons prepared by addition of nickel salts demonstrated higher specific capacitances than mesoporous carbons without nickel salts and the activated carbon electrodes. Their electrosorptive deionisation properties were also compared in a dilute NaCl solution (conductivity 100 μS cm−1), the amount of adsorbed ions are measured by a flow though apparatus in the laboratory. It is found that the amounts of the adsorbed ions are 15.9 μmol g−1 for OMCs involving nickel in the synthesis process, 10.3 μmol g−1 for OMC not involving nickel salts and 4.7 μmol g−1 for ACs.
The application of membrane bioreactors as decentralised systems for removal of endocrine disrupting chemicals and pharmaceuticals
Authors: Le-Minh N. , Coleman H. M. , Khan S. J. , van Luer Y. , Trang T. T. T. , Watkins G. , Stuetz R. M.
Published: March 2010

The concentrations of some important endocrine disrupting chemicals and pharmaceuticals after various stages of wastewater treatment were investigated. The endocrine disrupting chemicals included natural and synthetic estrogenic and androgenic steroids. The pharmaceuticals included a series of sulfonamide antibiotics and trimethoprim. The removal efficiency of a membrane bioreactor (MBR) was investigated and compared with a conventional activated sludge (CAS) system. Samples were analysed by liquid chromatography tandem mass spectrometry. Results showed that the MBR and CAS systems effectively removed steroidal estrogens and androgens, but only partially eliminated the target antibiotics from wastewater. The MBR was shown to be more effective than the CAS system which was possibly attributed to the high solid retention time and concentration of biosolids in the MBR. The results highlight the potential wider application of MBRs for the removal of trace chemical contaminants in wastewater and their potential for use as decentralised wastewater treatment systems.
Comparison between polishing (maturation) ponds and subsurface flow constructed wetlands (planted and unplanted) for the post-treatment of the effluent from UASB reactors
Authors: von Sperling M. , Dornelas F. L. , Assunção F. A. L. , de Paoli A. C. , Mabub M. O. A.
Published: March 2010

This paper presents the results of a comparison of the performance of two treatment systems operating in parallel, with the same influent wastewater. The investigated systems are (i) UASB + three polishing ponds in series + coarse filter (200 population equivalents) and (ii) UASB + subsurface flow constructed wetlands (50 population equivalents). Two wetland units, operating in parallel, were analysed, being one planted (Typha latifolia) and the other unplanted. The systems were located in Belo Horizonte, Brazil. The wetland systems showed to be more efficient in the removal of organic matter and suspended solids, leading to good effluent BOD and COD concentrations and excellent SS concentrations. The planted wetland performed better than the unplanted unit, but the latter was also able to provide a good effluent quality. The polishing pond system was more efficient in the removal of nitrogen (ammonia) and coliforms (E. coli). Land requirements and cost considerations are presented.
Nitrification–denitrification in waste stabilisation ponds: a mechanism for permanent nitrogen removal in maturation ponds
Authors: Camargo Valero M. A. , Read L. F. , Mara D. D. , Newton R. J. , Curtis T. P. , Davenport R. J.
Published: March 2010

A pilot-scale primary maturation pond was spiked with 15N-labelled ammonia (15NH4Cl) and 15N-labelled nitrite (Na15NO2), in order to improve current understanding of the dynamics of inorganic nitrogen transformations and removal in WSP systems. Stable isotope analysis of δ15N showed that nitrification could be considered as an intermediate step in WSP, which is masked by simultaneous denitrification, under conditions of low algal activity. Molecular microbiology analysis showed that denitrification can be considered a feasible mechanism for permanent nitrogen removal in WSP, which may be supported either by ammonia-oxidising bacteria (AOB) or by methanotrophs, in addition to nitrite-oxidising bacteria (NOB). However, the relative supremacy of the denitrification process over other nitrogen removal mechanisms (e.g., biological uptake) depends upon phytoplanktonic activity.
Analysis of a Model for Ethanol Production through Continuous Fermentation: Ethanol Productivity
Authors: Watt Simon , Sidhu Harvinder S , Nelson Mark I , Ray Ajay K.
Published: March 2010

We investigate a model for the production of ethanol through continuous fermentation using Saccharomyces cerevisiae in a single reactor and cascades of up to five reactors. Using path-following methods we investigate how the ethanol productivity varies with the residence time in each reactor of the cascade. With a substrate feed concentration of 160 g/l we find the optimal productivity is 3.80 g/l/h, 5.08 g/l/h, and 5.18 g/l/h in a single reactor, a double reactor cascade and a triple reactor cascade respectively. For the case of a cascade containing reactors of equal size we investigate reactor configurations of up to five reactors and find that the maximum productivity is obtained in a cascade containing three reactors.
Fuel Gas Production by Gasification of Glycerol Waste over Perovskite-Type Oxide Catalysts
Authors: Atong Duangduen , Ausadasuk Siritha , Sricharoenchaikul Viboon
Published: March 2010

Gasification of glycerol waste which is a by-product from biodiesel production was carried out using LaNiO3 and LaCoO3 perovskite-type oxide catalysts in order to enhance the production of fuel gas while reducing tar from the process. This present work showed that perovskite-type oxide could be effectively applied for cracking of tar from gasification of glycerol waste. The perovskite catalysts were prepared by a sol-gel process using PVA. The optimum condition for synthesis of LaCoO3 and LaNiO3 perovskite oxide was identified when the precursor was mixed metal ion and PVA containing a mole ratio of metal ion to PVA monomer unit as 1:1 and dried at 120°C for 20 h. The synthesized materials were calcined at different temperature and the phases were characterized with x-ray diffraction (XRD). The results showed that the single crystalline phase of perovskite without intermediate phases was achieved from calcination at 800°C for LaNiO3 and only 700°C for LaCoO3. The specific surface areas of LaNiO3 and LaCoO3 catalysts were in the range of 2.46-5.55 m2/g and 3.13-7.68 m2/g, respectively. SEM micrographs of catalyst illustrated a fluffy and foam structure with porous network. Catalytic activity of the prepared samples was tested by conversion of glycerol waste in a fixed-bed reactor. The catalytic reaction was carried out at a temperature of 500-800°C. At high temperatures LaNiO3 appeared to be a superior catalyst which enhanced the production of favorable gaseous species. However further gas upgrading may be required because of low LHV and H2/CO ratios obtained at these conditions.
Numerical Simulation of p-Xylene Synthesis via Selective Toluene Disproportionation over Modified ZSM-5 Catalyst
Authors: Ghoreishi Seyyed M. , Madani Seyyed H.
Published: March 2010

Numerical modeling of selective toluene disproportionation reaction over modified ZSM-5 zeolites to produce p-Xylene was developed and validated. The results of parametric analysis using the authenticated model provide an optimum guideline for the selection of appropriate operating conditions to achieve maximum toluene conversion and p-Xylene selectivity and yield. The predicted data indicate that increasing feed temperature from 450 to 600°C at constant (WHSV)-1 enhances the toluene conversion by 150%. Low weight hourly space velocities ((WHSV)-1=100 g.h/mol) and feed temperature (450°C) provides 99% p-Xylene selectivity. Moreover, at constant feed temperatures of 450, 500, 550 and 600°C, the maximum p-Xylene yield (? 0.087) occurs at 1300, 650, 330, and 175 g.h/mol, respectively, which clearly demonstrates that operation at higher feed temperature reduces the needed reactor residence time. Despite of imposed adiabatic condition, the model prediction demonstrates that an almost isothermal behavior prevails inside the reactor (2°C decrease in reactor temperature) due to the low heat of reaction (<1kJ/mol).
Thermodynamic and Kinetic Analysis of Ca-Based Oxygen Carrier in Chemical-Looping Combustion
Authors: Jing Chang , Dejie Cui
Published: March 2010

Chemical-looping combustion (CLC) is a promising technology to capture carbon dioxide (CO2) inherently and conveniently without the additional apparatus. At present, for some metal oxide oxygen carriers, the high costs and the positive hazards to the environment inhibit the developing of CLC systems. The feasibility of using CaSO4 oxygen carrier in the CLC system is studied in this paper. Through the thermodynamic analysis, the carbon deposition and the sulfur evolution are studied in the reaction between CaSO4 and a typical syngas. In addition, providing that hydrogen (H2) is fed as the gaseous fuel in the CLC system, the kinetic analysis is investigated on the reduction of CaSO4 by H2 and the oxidation of calcium sulfide (CaS) by oxygen (O2) through the thermo-gravimetric apparatus (TGA). The kinetic models are built on the reduction and the oxidation of the oxygen carrier. The results calculated from the models agree well with the experimental data. Finally, the possible reaction mechanisms for the reduction and the oxidation are explored.
The Development of Nurse Practitioner Preparation beyond the Master's Level: What is the Debate About?
Authors: Brar Kelly , Boschma Geertje , McCuaig Fairleth
Published: March 2010

The nursing discipline in the United States (US) has a history of creating various doctorates. One such degree, the Doctor of Nursing Practice (DNP), serves as an alternative to the traditional Doctor of Philosophy (PhD) degree for Nurse Practitioners (NPs) exploring career options. The availability of the DNP has sparked a debate within the profession: close attention to the issues is warranted for any school considering the development of a DNP program. However, some of these issues are not applicable, or apply differently to other contexts including Canada, where the highest level of education for an NP is a PhD. This article will review the history of doctoral education in both countries, compare the practice-focused and research-focused doctorates, discuss the issues of debate, and explore implications for NP practice. To fully inform the decision of the NP, we recommend further research to explore the need for a practice doctorate.
Preparation of Redispersible Emulsion Powder by Spray Drying
Authors: Yu Caiyuan , Ma Jingjing , Wang Wei
Published: March 2010

There is a large demand for redispersible emulsion powder in various industrial applications because of its unique features. However, the use of this novel material is hindered by the complex synthesis processing technology and consequently high cost. In this paper, a simple preparation method for building material used redispersable emulsion powder is proposed. This method mainly includes two steps, a core-shell emulsion polymerization reaction and a following spray drying. In the emulsion polymerization step, AVE and MMA were used as seed emulsion and shell monomer for the core-shell polymeric structure. The influences of various factors such as monomer ratio, emulsifier and initiator as well as the feed method on particle configuration of core-shell structure polymeric emulsion were investigated. The suitable conditions to prepare the emulsion powder are: SDS as the emulsifier, KPS as the initiator, 40°C of the reaction temperature, and 2:1 of the ratio of the core to shell with a semi-continuous process. The successful fabrication of core-shell bedded structure was verified with scanning electron microscope. In the following spray drying step, the optimized operation parameters are: 150°C of the inlet air temperature, 75°C of the outlet temperature, and 10.5 ml/min of the feed flow rate. Under optimized operating conditions, coated milk white emulsion powders with uniform size, good fluidity, and good membrane performance were obtained.
Cardiac-Specific IGF-1 Receptor Transgenic Expression Protects Against Cardiac Fibrosis and Diastolic Dysfunction in a Mouse Model of Diabetic Cardiomyopathy
Authors: Huynh Karina , McMullen Julie R. , Julius Tracey L. , Tan Joon Win , Love Jane E. , Cemerlang Nelly , Kiriazis Helen , Du Xiao-Jun , Ritchie Rebecca H.
Published: March 2010

OBJECTIVE

Compelling epidemiological and clinical evidence has identified a specific cardiomyopathy in diabetes, characterized by early diastolic dysfunction and adverse structural remodeling. Activation of the insulin-like growth factor 1 (IGF-1) receptor (IGF-1R) promotes physiological cardiac growth and enhances contractile function. The aim of the present study was to examine whether cardiac-specific overexpression of IGF-1R prevents diabetes-induced myocardial remodeling and dysfunction associated with a murine model of diabetes.

RESEARCH DESIGN AND METHODS

Type 1 diabetes was induced in 7-week-old male IGF-1R transgenic mice using streptozotocin and followed for 8 weeks. Diastolic and systolic function was assessed using Doppler and M-mode echocardiography, respectively, in addition to cardiac catheterization. Cardiac fibrosis and cardiomyocyte width, heart weight index, gene expression, Akt activity, and IGF-1R protein content were also assessed.

RESULTS

Nontransgenic (Ntg) diabetic mice had reduced initial (E)-to-second (A) blood flow velocity ratio (E:A ratio) and prolonged deceleration times on Doppler echocardiography compared with nondiabetic counterparts, indicative markers of diastolic dysfunction. Diabetes also increased cardiomyocyte width, collagen deposition, and prohypertrophic and profibrotic gene expression compared with Ntg nondiabetic littermates. Overexpression of the IGF-1R transgene markedly reduced collagen deposition, accompanied by a reduction in the incidence of diastolic dysfunction. Akt phosphorylation was elevated ∼15-fold in IGF-1R nondiabetic mice compared with Ntg, and this was maintained in a setting of diabetes.

CONCLUSIONS

The current study suggests that cardiac overexpression of IGF-1R prevented diabetes-induced cardiac fibrosis and diastolic dysfunction. Targeting IGF-1R–Akt signaling may represent a therapeutic target for the treatment of diabetic cardiac disease.
Association Between Glycemia, Serum Lipoproteins, and the Risk of Oral Leukoplakia
Authors: Meisel Peter , Dau Michael , Sümnig Wolfgang , Holtfreter Birte , Houshmand Mohammad , Nauck Matthias , Kocher Thomas
Published: March 2010

OBJECTIVE

Oral leukoplakia is an oral lesion with a premalignant character. Besides smoking and alcohol, diabetes could be a risk factor. The aim is to search for such an association.

RESEARCH DESIGN AND METHODS

Subjects with leukoplakia (N = 123) from the population-based Study of Health in Pomerania (SHIP) were matched 1:2 for age and sex with unaffected control subjects. Behavioral and lifestyle factors were assessed by a questionnaire. Lipoprotein concentrations, glycemia, and inflammation parameters were determined.

RESULTS

Subjects with oral leukoplakia showed higher levels of diabetes-related metabolites, a higher LDL/HDL cholesterol ratio (P = 0.004), and higher A1C (P = 0.002), and they were more frequently smokers (P < 0.001). Assessed by conditional logistic regression, the probability of leukoplakia increases with current smoking (odds ratio 2.20 [95% CI 1.16–4.17]) and higher levels of A1C (1.51 [95% CI 1.08–2.12]), revealing interaction between both factors (P = 0.012).

CONCLUSIONS

Diabetes is associated with the risk of oral leukoplakia, which is exaggerated by smoking. The risk is positively correlated with A1C concentrations.
Explanations for the Lower Rates of Diabetic Neuropathy in Indian Asians Versus Europeans
Authors: Abbott Caroline A. , Chaturvedi Nishi , Malik Rayaz A. , Salgami Eleanna , Yates Allen P. , Pemberton Philip W. , Boulton Andrew J.M.
Published: March 2010

OBJECTIVE

Risks of diabetes and cardiovascular disease are elevated worldwide in Indian Asians. However, risks of other diabetes-related complications, i.e., foot ulceration and amputation, also with a vascular basis, are substantially lower in Asians than in white Europeans in the U.K., possibly due to less neuropathy. We therefore compared signs, symptoms, and objective quantitative measures of diabetic neuropathy and their risk factors in Indian Asians and Europeans.

RESEARCH DESIGN AND METHODS

This was a cross-sectional study of a population-based sample of age- and sex-matched adults with type 2 diabetes of European (95 male and 85 female) and Asian (96 male and 84 female) descent in the U.K. Patients were assessed for neuropathic symptoms, signs, nerve conduction, autonomic function, and quantitative sensory testing. Peripheral vascular function and other potential risk factors for neuropathy were measured.

RESULTS

Mean nerve conduction velocity Z scores were better in Asians (mean ± SD 0.07 ± 0.62) than in Europeans (−0.11 ± 0.60; P = 0.007) and were explained by the shorter height, fewer pack-years smoked, and higher transcutaneous oxygen levels (TCpO2) in Indian Asians (P value for ethnic comparison attenuated to 0.2). Small fiber neuropathy was less prevalent in Indian Asians compared with Europeans (odds ratio 0.58 [95% CI 0.37–0.93]; P = 0.02) and was primarily accounted for by better TCpO2 (0.70 [0.40–1.21]; P = 0.2).

CONCLUSIONS

Asians with diabetes have substantially less large and small fiber neuropathy than Europeans, despite comparable traditional risk factors. Independent from smoking, the lower risk of neuropathy in Asians is due to better skin microvascularization and may help explain the substantially reduced Asian foot ulcer risk.
Glucose Intolerance and Cardiometabolic Risk in Adolescents Exposed to Maternal Gestational Diabetes
Authors: Tam Wing Hung , Ma Ronald Ching Wan , Yang Xilin , Li Albert Martin , Ko Gary Tin Choi , Kong Alice Pik Shan , Lao Terence Tzu Hsi , Chan Michael Ho Ming , Lam Christopher Wai Kei , Chan Juliana Chung Ngor
Published: March 2010

OBJECTIVE

Adolescent offspring of women with a history of gestational diabetes (GD) were evaluated for their cardiometabolic risks at a mean age of 15 years.

RESEARCH DESIGN AND METHODS

One hundred and twenty-nine adolescents who were assessed for their cardiometabolic risks at 8 years of age were reassessed at 15 years of age.

RESULTS

Adolescent offspring of mothers with GD had similar blood pressure, plasma lipid profile, and a rate of abnormal glucose tolerance as control subjects. In utero hyperinsulinemia was associated with a 17-fold increase in metabolic syndrome and a 10-fold increase in overweight at adolescence, independent of birth weight, Tanner stage, maternal GD status, and mother's BMI.

CONCLUSIONS

In utero environment of hyperinsulinemia, irrespective of the degree of maternal GD, was associated with increased risk of overweight and metabolic syndrome during early adolescence in the offspring.
Effects of Cardiac Autonomic Dysfunction on Mortality Risk in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) Trial
Authors: Pop-Busui Rodica , Evans Gregory W. , Gerstein Hertzel C. , Fonseca Vivian , Fleg Jerome L. , Hoogwerf Byron J. , Genuth Saul , Grimm Richard H. , Corson Marshall A. , Prineas Ronald ,   the ACCORD Study Group
Published: March 2010

OBJECTIVE

Intensive therapy targeting normal blood glucose increased mortality compared with standard treatment in a randomized clinical trial of 10,251 participants with type 2 diabetes at high-risk for cardiovascular disease (CVD) events. We evaluated whether the presence of cardiac autonomic neuropathy (CAN) at baseline modified the effect of intensive compared with standard glycemia treatment on mortality outcomes in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial participants.

RESEARCH DESIGN AND METHODS

CAN was assessed by measures of heart rate variability (HRV) and QT index (QTI) computed from 10-s resting electrocardiograms in 8,135 ACCORD trial participants with valid measurements (mean age 63.0 years, 40% women). Prespecified CAN definitions included a composite of the lowest quartile of HRV and highest QTI quartile in the presence or absence of peripheral neuropathy. Outcomes were all-cause and CVD mortality. Associations between CAN and mortality were evaluated by proportional hazards analysis, adjusting for treatment group allocation, CVD history, and multiple prespecified baseline covariates.

RESULTS

During a mean 3.5 years follow-up, there were 329 deaths from all causes. In fully adjusted analyses, participants with baseline CAN were 1.55–2.14 times as likely to die as participants without CAN, depending on the CAN definition used (P < 0.02 for all). The effect of allocation to the intensive group on all-cause and CVD mortality was similar in participants with or without CAN at baseline (Pinteraction > 0.7).

CONCLUSIONS

Whereas CAN was associated with increased mortality in this high-risk type 2 diabetes cohort, these analyses indicate that participants with CAN at baseline had similar mortality outcomes from intensive compared with standard glycemia treatment in the ACCORD cohort.
Wing lengths of Clamorous Reed Warblers Acrocephalus stentoreus in Israel
Authors: Morgan John
Published: March 2010

Wing lengths of Clamorous Reed Warblers Acrocephalus stentoreus in Israel

Wing length measurements taken from first-year, pre- and post-moulting (annual, complete) Clamorous Reed Warblers were recorded at a site in northern Israel. The resulting data set was examined using a time-series of residuals (CUSUM). Results from this analysis can explain the reported heterogeneity found in a comparable data set by Merom et al. (1999). Further observations made in their paper are rebutted: (1) an implied assumption that Reed Warbler (Acrocephalus scirpaceus) spring migration in Israel ends by 1 May is contrary to other publications; (2) the late autumn occurence in N Israel of longer-winged 1st cal. yr. Reed Warblers, unconvincingly explained as either delayed migration by larger individuals or post fledging feather growth, is most likely due to birds from different provenances origins moving at different seasons; (3) growth during adulthood in Reed Warbler is not a new discovery, though presented as such.
Use of AFLP molecular markers for estimating genetic similarity of alfalfa (Medicago sativa L. Sl.)
Authors: Dobrzycka Agnieszka , Broda Zbigniew , Bocianowski Jan , Ćwiklinska Anna
Published: March 2010

Use of AFLP molecular markers for estimating genetic similarity of alfalfa (Medicago sativaL. Sl.)

The aim of study was to determine genetic similarity among sixteen alfalfa populations using the AFLP technique. Plant material was selected considering the high genotypic variability. It included populations of different origin: native forms of alfalfa (secondary ecotypes), inbred lines, single hybrids, synthetic populations, varieties and mutants. Analysis was carried out using 10 combinations of primers. It was noticed, that in case of the studied alfalfa populations, the highest polymorphism was obtained using primers with three selective nucleotides. The genetic similarity coefficients were calculated by the method of Nei and Li. Those coefficients were used for the hierarchical grouping of objects by the unweighted pair group method of arithmetic means. Results of the grouping were presented in the form of dendrogram. Values of coefficients ranged from 0.3311 (between the inbred F line and the Ulstar variety) to 0.8076 (between ecotype 27 and the synthetic population Syn 7-3). Dendrogram of genetic similarity obtained in this way did not fully correspond with the known data about the studied populations' origin. Considering the genetic similarity, inbreed line F was the most outlying from the studied populations of alfalfa.
Evolution of the Concept Map Based Adaptive Knowledge Assessment System: Implementation and Evaluation Results
Authors: Grundspenkis Janis , Anohina Alla
Published: March 2010

Evolution of the Concept Map Based Adaptive Knowledge Assessment System: Implementation and Evaluation Results

The paper represents the concept map based adaptive knowledge assessment system. Advantages of concept maps are analyzed emphasizing that the approach offers a reasonable balance between requirements to assess higher levels of knowledge according to Bloom's taxonomy and complexity of a system. Concept maps allow revealing of student's knowledge structure, promote system thinking and support process oriented learning where a study course is divided into stages in each of which knowledge assessment is carried out. The developed knowledge assessment system consists from a teacher's, learner's and administrator's modules and is implemented as a multiagent system. Four prototypes of the system developed within four projects are described. The first prototype supports only fill-in-the-map tasks where a learner must put given concepts in correct places. The second prototype provides changing the degree of task difficulty, thus, performing adaptation to a learner's knowledge level. The set of tasks are also extended by construct-the-map tasks. Improvements implemented in the third prototype allow using of directed arcs and standard relationships in concept maps. The three-tier architecture used in the fourth prototype is chosen to rise the security level of the system. Besides that learner's support is considerably expanded giving help and tutoring to a learner. Results of evaluation of the developed system's prototypes in different study courses are presented. The paper concludes with the comparison of all four prototypes using all main characteristics of the developed knowledge assessment system.
Knowledge assessment systems: an overview
Authors: Lukashenko Romans , Anohina Alla
Published: March 2010

Knowledge assessment systems: an overview

The paper gives on overview of computer-assisted assessment systems. The general definition of computer-assisted assessment is provided and the application of objective and subjective testing systems is described. Moreover, advantages and drawbacks related both to computer-assisted assessment in general and to objective and subjective testing systems in particular are identified. The overall architecture of a computer-assisted assessment system in terms of components, their functions and interaction is presented. The necessity to provide intelligent and adaptive support in computer-assisted assessment systems is stated and kinds of the mentioned support in existent systems are described. Special attention is devoted to the student model that is used with the aim to adapt the system to the needs of a specific user. The basic kinds of information stored in the student model and their sources are defined, as well as the available classifications of the student model on the basis of different criteria are summarized. The paper also provides information on intelligent and adaptive support in the concept map based knowledge assessment system that has been developed at Riga Technical University, as well as identifies further development directions of the mentioned system.