bluuebunny/crossref_metadata_2025 huggingface dataset:
COMMENT: CHEMICAL AND MINERALOGICAL APPROACHES TO CERAMIC PROVENANCE DETERMINATION
Authors: NEFF H.
Published: August 2011

This comment concerns an ‘absolutist’ perspective on the superiority of mineralogical analysis over chemical analysis for the determination of ceramic provenance. This point of view has appeared in the literature in recent years, but it has not been justified and is not justifiable. Mineralogy and chemistry are complementary. They measure different things and are best used in combination to generate secure, geographically specific ceramic source assignments.
On Educational Performance Measures*
Authors: Muriel Alastair , Smith Jeffrey
Published: August 2011

Quantitative performance measures (QPMs) of schools are playing an ever‐larger role in education systems on both sides of the Atlantic. In this paper, we outline the rationale for the use of such measures in education, review the literature relating to several important problems associated with their use and argue that they nonetheless have a positive role to play in improving the quality of education. We delineate several institutional reforms that would help schools to respond ‘positively’ to QPMs, emphasising the importance of agents' flexibility to change the way they work and the importance of a sound knowledge base regarding ‘what works’ in raising attainment. We suggest that the present institutional set‐ups in both England and the US too often hold schools accountable for outcomes over which they have little control – but that such problems are far from insurmountable.
Understanding Uncertainty in School League Tables*
Authors: Leckie George , Goldstein Harvey
Published: August 2011

In England, contextual value added (CVA) school performance tables are published annually by the government. These tables present statistical‐model‐based estimates of the educational effectiveness of schools, together with 95 per cent confidence intervals to communicate their statistical uncertainty. However, this information, particularly the notion of statistical uncertainty, is hard for users to understand. There is a real need to make school performance tables clearer. The media attempt to do this for the public by ranking schools in so‐called ‘school league tables’; however, they invariably discard the 95 per cent confidence intervals and, in doing so, encourage the public to over‐interpret differences in schools' ranks. In this paper, we explore a simulation method to produce simple graphical summaries of schools' ranks that clearly communicate their associated uncertainty.
In Vitro Evaluation of a Compliant Inflow Cannula Reservoir to Reduce Suction Events With Extracorporeal Rotary Ventricular Assist Device Support
Authors: Gregory Shaun David , Timms Daniel , Gaddum Nicholas Richard , McDonald Charles , Pearcy Mark John , Fraser John F.
Published: August 2011

Limited preload sensitivity of rotary left ventricular assist devices (LVADs) renders patients susceptible to harmful atrial or ventricular suction events. Active control systems may be used to rectify this problem; however, they usually depend on unreliable sensors or potentially inaccurate inferred data from, for example, motor current. This study aimed to characterize the performance of a collapsible inflow cannula reservoir as a passive control system to eliminate suction events in extracorporeal, rotary LVAD support. The reservoir was evaluated in a mock circulation loop against a rigid cannula under conditions of reduced preload and increased LVAD speed in both atrial and ventricular cannulation scenarios. Both cases demonstrated the ease with which chamber suction events can occur with a rigid cannula and confirm that the addition of the reservoir maintained positive chamber volumes with reduced preload and high LVAD speeds. Reservoir performance was dependent on height with respect to the cannulated chamber, with lower placement required in atrial cannulation due to reduced filling pressures. This study concluded that a collapsible inflow cannula is capable of minimizing suction events in extracorporeal, rotary LVAD support.
How Can We Achieve Infection‐Resistant Percutaneous Energy Transfer?
Authors: Affeld Klaus , Grosshauser Johannes , Reiter Katja , Grosse‐Siestrup Christian , Kertzscher Ulrich
Published: August 2011

Clinical records show ever increasing functional times of rotary blood pumps implanted in patients. With longer functional time, the problem of driveline infection is becoming more urgent. No material or scaffold has been found, which allows a permanent and stable ingrowth of skin cells that would prevent (pathogenic) germs entering the body. Usually, the epithelial cells die at the exit site and new cells form a sulcus around the driveline, which grows deeper and finally becomes infected. The purpose of this project is to present a solution to this problem by elaborating a new mechanism, the active skin‐penetrating device. The device is composed of a tube with a 5‐mm diameter, a protective sleeve that surrounds the catheter exit site, and an active traction device. The protective sleeve is made of thin polyurethane covered with polyethylenterephtalat (PET, i.e. Dacron) fibers to permit the attachment of keratinocytes, similar to the standard driveline. The active traction device exerts a constant pull on the protective sleeve. The ingrown keratinocytes slowly give way and the protective sleeve gradually moves out of the body at a rate of a few millimeters per week. Meanwhile, the keratinocytes transform into horny cells and are then shed as in natural skin. Therefore, the formation of a sulcus is avoided, and the protective sleeve remains infection‐free. In a first proof of the concept, four of the new devices and 10 control devices were implanted in goats. The devices remained infection‐free for a period of 420 days, whereas four of the 10 control devices became infected. On the basis of these experiments, the active skin‐penetrating device has been further developed and is being tested again in goats in a refined version. The results so far indicate that with the active‐skin penetrating device an infection‐resistant percutaneous energy transfer can be achieved for a prolonged period of time.
Intuitive Use and Usability of Ventricular Assist Device Peripheral Components in Simulated Emergency Conditions
Authors: Geidl Lorenz , Deckert Zeno , Zrunek Philipp , Gottardi Roman , Sterz Fritz , Wieselthaler Georg , Schima Heinrich
Published: August 2011

Ventricular assist devices (VADs) are now increasingly used to prolong the lives of end‐stage heart failure patients. These patients vary greatly in age, alertness, activity, and home environment. In daily routine, but especially in emergencies or in conjunction with non‐VAD‐correlated diseases, the untrained, intuitive use and application of VAD peripherals by relatives, laypersons, and paramedics becomes important. Correct intuitive use may be a matter of life and death. The aim of this study was to evaluate the intuitive usability of these systems and to identify key features needed to optimize intuitive use. Paramedics (n = 96) were confronted with a simulated emergency situation involving VAD peripherals mounted on a dummy. Three conditions were simulated: the VAD disconnected from its power source (n = 44); both VAD batteries empty (n = 44); and a discharged VAD battery mistakenly connected in place of a charged one (n = 8). Two VAD systems were assessed: the Heartware HVAD and the Thoratec HeartMate II. An appropriate emergency card developed by our center was available in each case. Actions were videotaped, response times were measured, and a standardized questionnaire was completed after the simulation. The problem was solved by 71% of the participants (HVAD 83%, HMII 60%) with 87% using the emergency card. Only 4% could solve the problem without. Cardiac massage, which was unnecessary, was started by 44%, while 18% complained about unnecessarily difficult conditions (e.g., irritation from the acoustic alarm, complexity of the emergency card, error‐prone procedures). Better component labeling (e.g., displays, control elements, connectors) was recommended by 56%. A thoroughly color‐coded connection system was especially desired. Cable‐ and connector‐related difficulties were reported by 23%. The study indicated that VAD systems should be self‐explaining, with clear labeling of components and connectors, that a clearer emergency card is pivotal and that similar basic handling and emergency procedures for all VAD types would be desirable.
Three‐dimensional bone structure and bone mineral density evaluations of autogenous bone graft after sinus augmentation: a microcomputed tomography analysis
Authors: Huang Heng‐Li , Chen Michael YC , Hsu Jui‐Ting , Li Yu‐Fen , Chang Chih‐Han , Chen Kuan‐Ting
Published: August 2011

Objective

The purpose of this study was to determine the relationships and differences in three‐dimensional (3D) bone mineral density (BMD) and microtrabecular structures between autogenous bone grafts and their adjacent native bone after a healing period following maxillary sinus augmentation.

Materials and methods

Nine rod‐shaped human bone biopsy samples were taken from patients receiving two‐stage sinus augmentation therapy in implantation areas and analyzed using microcomputed tomography (micro‐CT). Before micro‐CT scanning, two BMD phantoms were placed near to the bone biopsy samples for executing BMD calculations of the grafted and native bone samples. In addition, 3D structural parameters of the trabeculae were analyzed for both the grafted and native bone, including percentage of bone volume [bone volume (BV)/tissue volume (TV)], bone‐specific surface [bone surface (BS)/BV], trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), trabecular pattern factor (Tb.Pf), and structure model index (SMI).

Results

No significant correlations with regard to BMD and trabecular‐structure parameters were found between native bone and grafted bone; however, BS/BV and Tb.Pf were higher and Tb.Th and Tb.Sp were 37.35% and 12.74% lower in grafted bone than in native bone. For grafted bone, there were significant correlations (P < 0.05) between BMD and BV/TV, and Tb.N.

Conclusions

When using autogenous bone as a graft material, BMD and micromorphological conditions of grafted bone were not influenced by the condition of the native bone in the maxilla. Differences were found in surface complexity, trabecular thickness, trabecular separation, and the connectivity of trabeculae between grafted and native bone. The BMD in grafted bone was affected by the quantity of the trabeculae.
Heat Transport by Inverse-Piezoelectric Driven Dream
Pipe
Authors: Furukawa Masao
Published: August 2011

A novel type of so-called dream pipe is introduced hoping for the high-efficiency heat removal. Unlike traditional types with mechanical shaker, this one fits up an inverse-piezoelectric-cells embedded thin disk coupled with ac power to cause oscillatory pipe flows. A theoretical approach is adopted to comprehensively describe thermal characteristics of that new device. With a view to obtaining more practical expressions than accepted before, the Galerkin method based on the variational principle is used to solve governing partial differential equations. The induced tidal displacement and the relative increase of thermal diffusivity are expressed in reduced algebraic form. Also presented are design formulas defining the specific driving power and the specific number of required tubes. Concerning the effective thermal diffusivity, the author’s predictions are fairly well consistent with exact ones deduced from Watson’s expression. Ratios of the two are linearly regressed to a cubic equation applicable to the frequency range from 0.5 Hz to 6.0 Hz. Recommendable coefficient values are listed in the table. Possible combinations of four fluids of interest and seven levels of the applied ac voltage are considered in a parametric study. Numerical results are graphically shown in the figures for discussion on the feasibility.
Prediction of PF-5060 Spray Cooling Heat Transfer and Critical Heat Flux
Authors: Abbasi Bahman , Kim Jungho
Published: August 2011

Spray cooling heat transfer measurements of PF-5060 on smooth flat surfaces were obtained using a microheater array operated at constant temperatures using two nozzles (hollow cone and full cone), three nozzle-to-heater standoff distances (3, 5, and 7 mm), four nozzle operating pressures (207 kPa, 345 kPa, 483 kPa, and 689 kPa), and three subcooling levels (11 °C, 21 °C, 31 °C). A separate test setup was used to measure the local normal pressures produced by the sprays. The critical heat flux was found to depend primarily on the local normal pressure and the liquid subcooling. Furthermore, the temperature at which CHF occurred was within a narrow temperature band (about ±5 °C) for smooth flat surfaces over a wide range of spray conditions. The single-phase correlation previously proposed by the authors and the CHF correlation presented in this work were then combined to predict local spray cooling curve within ±25% of the measured values in the spray impingement zone.
Entrance
and Temperature Dependent Viscosity Effects on Laminar Forced Convection in Straight Ducts With
Uniform Wall Heat Flux
Authors: Giudice Stefano Del , Savino Stefano , Nonino Carlo
Published: August 2011

In this paper a parametric investigation is carried out on the effects of temperature dependent viscosity in simultaneously, i.e., hydro-dynamically and thermally, developing laminar flows of liquids in straight ducts of constant cross sections. Uniform heat flux boundary conditions are imposed on the heated walls of the ducts. Different cross-sectional geometries are considered, corresponding to both axisymmetric (circular and concentric annular) and three-dimensional (rectangular and trapezoidal) ducts. Viscosity is assumed to vary with temperature according to an exponential relation, while the other fluid properties are held constant. A finite element procedure is employed for the solution of the parabolized momentum and energy equations. Computed axial distributions of the local Nusselt number and of the apparent Fanning friction factor are presented for different values of the Pearson and Prandtl numbers. Numerical results confirm that, in the laminar forced convection in the entrance region of straight ducts, the effects of temperature dependent viscosity cannot be neglected in a wide range of operative conditions. Correlations are also provided for the local Nusselt number and the apparent Fanning friction factor in simultaneously developing flows in ducts of different cross sections.
A Cyclic Robot for Lower Limb Exercise
Authors: DeJong Brian P. , Colgate J. Edward , Peshkin Michael A.
Published: August 2011

This paper presents the design and simulation of a cyclic robot for lower-limb exercise robots. The robot is designed specifically for cyclic motions and the high power nature of lower-limb interaction—as such, it breaks from traditional robotics wisdom by intentionally traveling through singularities and incorporating large inertia. Such attributes lead to explicit design considerations. Results from a simulation show that the specific design requires only a reasonably sized damper and motor.
On Modeling Assumptions in Finite Element Analysis of Stents
Authors: Rebelo Nuno , Radford Rob , Zipse Achim , Schlun Martin , Dreher Gael
Published: August 2011

Finite Element Analysis (FEA) of Nitinol medical devices has become prevalent in the industry. The analysis methods have evolved in time with the knowledge about the material, the manufacturing processes, the testing or in vivo loading conditions, and the FEA technologies and computing power themselves. As a result, some common practices have developed. This paper presents a study in which some commonly made assumptions in FEA of Nitinol devices were challenged and their effect was ascertained. The base model pertains to the simulation of the fabrication of a diamond shape stent specimen, followed by cyclic loading. This specimen is being used by a consortium of several stent manufacturers dedicated to the development of fatigue laws suitable for life prediction of Nitinol devices. The FEA models represent the geometry of the specimens built, for which geometrical tolerances were measured. These models use converged meshes, and all simulations were run in the FEA code Abaqus making use of its Nitinol material models. Uniaxial material properties were measured in dogbone specimens subjected to the same fabrication process as the diamond specimens. By convention, the study looked at computed geometry versus measured geometry and at the maximum principal strain amplitudes during cyclic loading. The first aspect studied was the effect of simulating a single expansion to the final diameter compared to a sequence of three partial expansions each followed by shape setting. The second aspect was to ascertain whether it was feasible to conduct the full analysis with a model based on the electropolished dimensions or should an electropolish layer be removed only at the end of fabrication, similar to the manufacturing process. Finally, the effect of dimensional tolerances was studied. For this particular geometry and loading, modeling of a single expansion made no discernable difference. The fabrication tolerances were so tight that the effect on the computed fatigue drivers was also very small. The timing of the removal of the electropolished layer showed an effect on the results. This may have been so, because the specimen studied is not completely periodic in the circumferential direction.
Optimization of postgrowth electron-beam curing for focused electron-beam-induced Pt deposits
Authors: Plank Harald , Kothleitner Gerald , Hofer Ferdinand , Michelitsch Stephan G. , Gspan Christian , Hohenau Andreas , Krenn Joachim
Published: August 2011

The authors use focused electron-beam-induced Pt deposition from a gaseous (CH3)3CH3C5H4Pt precursor for the fabrication of electrically conductive structures consisting of Pt nanocrystals embedded in a carbon containing matrix. Recently it has been demonstrated that the electrical resistivity of such deposits can be strongly improved via postgrowth electron irradiation. This study shows very strong evidence that incompletely and nondissociated precursor molecules incorporated within the deposits during deposition are the key elements for efficient e-beam curing. During the early stages of e-beam curing these fragments are further dissociated, which leads to slight growth of the Pt nanocrystals. This is further supported by variable growth regime experiments during deposition which can be used to enhance the incorporation of incompletely and nondissociated precursor molecules, resulting in higher curing efficiencies and lower electrical resistivities. The absence of a predominant graphitization of the surrounding carbon matrix during this dissociation dominated curing regime suggests strongly that the observed resistivity decrease is mainly caused by the formation of preferred tunnel percolation paths due to reduced intercrystallite distances. Furthermore, it is shown that deposit height and the electron-beam energy used for curing should be adapted to each other to achieve the fastest curing time and the lowest electrical resistivities. Such optimized procedures allow then for curing rates higher than 1.5 μm2 min−1 and resistivity decreased to 5 ± 0.4 × 104 μΩ cm, representing an improvement of up to 3 orders of magnitude.
Indium nitride epilayer prepared by UHV-plasma-assisted metalorganic molecule beam epitaxy
Authors: Chen Wei-Chun , Kuo Shou-Yi , Lai Fang-I , Lin Woei-Tyng , Hsiao Chien-Nan , Tsai Din Ping
Published: August 2011

Indium nitride films grown at various growth temperatures were prepared on GaN buffer layers using self-designed plasma-assisted metal-organic molecular beam epitaxy. The influence of substrate temperature on film crystallinity, surface morphology, optical, and electrical properties was studied using x-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), UV/VIS/NIR spectrophotometer, and Hall measurement. The results show that the InN films grown on the GaN template at 500 oC are of good quality, and the full width at half maximum of InN(0002) ω-scan is around 1000 arc sec. The SEM images revealed that the average growth rate is 1.1 μm/h, which is comparable to the conventional epitaxial techniques. These results indicate that the electronic properties and crystalline quality can be significantly improved by optimizing the growth temperature.
Influence of sputtering pressure on band gap of Zn1−xMgxO thin films prepared by radio frequency magnetron sputtering
Authors: Wang Dapeng , Narusawa Tadashi , Kawaharamura Toshiyuki , Furuta Mamoru , Li Chaoyang
Published: August 2011

Zn1−xMgxO thin films were deposited onto quartz glass substrates using a radio frequency magnetron sputtering at various deposition pressures. It was found that the Mg concentration in the Zn1−xMgxO thin films significantly increased by decreasing the deposition pressure from 9 to 1 Pa, which contributed to an increase in the band gap of the ZnMgO films. In addition, the Zn1−xMgxO thin films, which had a hexagonal wurtzite structure when obtained by high pressure deposition (7 and 9 Pa) at x ≤ 0.478, had a cubic rock-salt crystal structure when deposition pressure was decreased to 1–5 Pa at x ≥ 0.482. These results show that the band gap of the ZnMgO thin films could be easily modulated only by adjusting of the deposition pressure during the radio frequency sputtering process.
Phase, grain structure, stress, and resistivity of sputter-deposited tungsten films
Authors: Choi Dooho , Wang Bincheng , Chung Suk , Liu Xuan , Darbal Amith , Wise Adam , Nuhfer Noel T. , Barmak Katayun , Warren Andrew P. , Coffey Kevin R. , Toney Michael F.
Published: August 2011

Sputter-deposited W films with nominal thicknesses between 5 and 180 nm were prepared by varying the base pressure prior to film deposition and by including or not including sputtered SiO2 encapsulation layers. X-ray and electron diffraction studies showed that single phase, polycrystalline α-W could be achieved in as-deposited films as thin as 5 nm. The stress state in the as-deposited films was found to be inhomogeneous. Annealing resulted in stress relaxation and reduction of resistivity for all films, except the thinnest, unencapsulated film, which agglomerated. In-plane film grain sizes measured for a subset of the annealed films with thicknesses between 5 and 180 nm surprisingly showed a near constant value (101–116 nm), independent of film thickness. Thick-film (≥120 nm) resistivity values as low as 8.6 μΩ cm at 301 K were obtained after annealing at 850 °C for 2 h. Film resistivities were found to increase with decreasing film thicknesses below 120 nm, even for films which are fully A2 α-W with no metastable, A15 β-W evident.
Photovoltaic characteristics of a-Si/β-FeSi2/c-Si double heterojunction fabricated by magnetron sputtering
Authors: Xu Jiaxiong , Yao Ruohe , Geng Kuiwei
Published: August 2011

A novel β-FeSi2 solar cell with amorphous-Si/β-FeSi2/crystalline-Si (a-Si/β-FeSi2/c-Si) double heterojunction structure was investigated. The c-Si (100) wafers were used as substrate materials. Polycrystalline β-FeSi2 thin film and a-Si thin film were grown by magnetron sputtering. In dark condition, the a-Si/β-FeSi2/c-Si heterojunction showed a better rectifying property than that of the β-FeSi2/crystalline-Si (β-FeSi2/c-Si) heterojunction. Under air mass 1.5 illumination, the measured conversion efficiency of a-Si/β-FeSi2/c-Si heterojunction increased by 59.7% compared with that of β-FeSi2/c-Si heterojunction. The effective enhancement of photovoltaic performance was ascribed to the extended built-in electric field distribution and the increased built-in potential. These results illustrated an attractive way to improve the conversion efficiency of β-FeSi2 solar cells by using the double heterojunction.
Safety considerations for IMRT: Executive summary
Authors: Moran Jean M. , Dempsey Melanie , Eisbruch Avraham , Fraass Benedick A. , Galvin James M. , Ibbott Geoffrey S. , Marks Lawrence B.
Published: August 2011

This report on intensity‐modulated radiation therapy (IMRT) is part of a series of white papers addressing patient safety commissioned by the American Society for Radiation Oncology's (ASTRO) Target Safely Campaign. The document has been approved by the ASTRO Board of Directors, endorsed by the American Association of Physicists in Medicine (AAPM) and American Association of Medical Dosimetrists (AAMD), and reviewed and accepted by the American College of Radiology's Commission on Radiation Oncology. This report is related to other reports of the ASTRO white paper series on patient safety which are still in preparation, and when appropriate it defers to guidance that will be published by those groups in future white papers. This document takes advantage of the large body of work on quality assurance and quality control principles within radiation oncology whenever possible. IMRT provides increased capability to conform isodose distributions to the shape of the target(s), thereby reducing dose to some adjacent critical structures. This promise of IMRT is one of the reasons for its widespread use. However, the promise of IMRT is counterbalanced by the complexity of the IMRT planning and delivery processes, and the associated risks, some of which have been demonstrated by the New York Times reports on serious accidents involving both IMRT and other radiation treatment modalities. This report provides an opportunity to broadly address safe delivery of IMRT, with a primary focus on recommendations for human error prevention and methods to reduce the occurrence of errors or machine malfunctions that can lead to catastrophic failures or errors.
Modeling of [AlO4/Li+]+ paramagnetic defects in α-quartz
Authors: Botis Sanda M. , Pan Yuanming
Published: August 2011

Two types of [AlO4/Li+]+ paramagnetic defects in α-quartz have been detected and quantitatively characterized by previous EPR experiments but remain unclear with respect to structures and formation mechanisms. We have investigated these [AlO4/Li+]+ paramagnetic defects in α-quartz by ab initio calculations at the density functional theory (DFT) level, using 72- and 108-atom supercells and all-electron basis sets. Our results show that the Al–Li coupled substitution could give rise to three distinct paramagnetic defects, two of them having the hole located on a short-bonded O atom and one trapping the hole on a long-bonded O atom. The structural models from our calculations are [AlO4/Li+(a<)]+, [AlO4/Li+(a>)]+, and [AlO4/Li+(csmall)]+ with a<, a>, and csmall indicating the position of the Li+ ion. Our calculated hyperfine constants and nuclear quadrupole parameters are in agreement with those determined from previous EPR experiments. The present study clarifies the ambiguities related to the structural model of the [AlO4/Li]q centre, discovered and proposed by Walsby et al. (Can. J. Phys. 81, 583 (2003)), and eliminates the uncertainties related to the charge of the compensating Li ion. We also suggest an additional paramagnetic defect [AlO4/Li+(csmall)]+, with the unpaired electron located on a short-bonded O atom and the Li compensator just off the edge of the small channel. However, the structural similarities with the [AlO4/Li+(a>)]+ defect would require detection and measurement of the 17O hyperfine structure for an unequivocal EPR identification.
Influencing parameters for the achievement of porphyrin supramolecular architectures on mesoporous metal oxide nanoparticles
Authors: Planells Miquel , González Almudena , Ballester Pablo , Palomares Emilio
Published: August 2011

We describe the spectroscopic characterization of a supramolecular trisporphyrin complex that is heterogeneously self-assembled onto mesoporous Al2O3 films and can be used as efficient light harvesting complex. The parameters for an efficient complexation process, such as dye loading, are evaluated and discussed. In addition, the heterosupramolecular complex is tested on TiO 2 nanoparticles and the charge transfer process elucidated.
Porphyrin analogs bearing exocyclic double bonds at meso-positions: bis(meso-diethylmalonylidene)-(1,4-naphthi)thiaporphyrin
Authors: Yoo Jaeduk , Kim Hyun-Jin , Kim Han-Je , Lee Chang-Hee
Published: August 2011

meso-diethylmalonylidene-(1,4-naphthi)thiaporphyrin containing exocyclic C – C double bonds at meso-positions has been synthesized and characterized. The compound undergoes initial protonation at the α-position of the diethylmalonyl group with large red shifted absorption maxima. The second protonation occurs at a meso-position to give a species with broken cross-conjugation.
Boronic esters of a porphyrazine and its precursor
Authors: Başeren Şükran Cenikli , Özçelik Şennur , Gül Ahmet
Published: August 2011

Phenylboronic acid esters of an unsaturated precursor 1,2-dicyano-1,2-bis(2-hydroxy- ethylthio)ethylene and the magnesium porphyrazine derived from it have been prepared either by refluxing a mixture of the reagents in chloroform in the presence of molecular sieve or by solvent-free heating in an oven under reduced pressure. The two novel compounds have been characterized by elemental analysis together with ultraviolet-visible, infrared spectroscopy, proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, boron-11 nuclear magnetic resonance, and mass spectra.
PARTICLE SWARM OPTIMIZATION ON FLEXIBLE DOCKING
Authors: LIU YU , LI WENTAO , MA RUIXIN
Published: August 2011

Molecular docking is an important tool in screening large libraries of compounds to determine the interactions between potential drugs and the target proteins. The molecular docking problem is how to locate a good conformation to dock a ligand to the large molecule. It can be formulated as a parameter optimization problem consisting of a scoring function and a global optimization method. Many docking methods have been developed with primarily these two parts varying. In this paper, a variety of particle swarm optimization (PSO) variants were introduced to cooperate with the semiempirical free energy force field in AutoDock 4.05. The search ability and the docking accuracy of these methods were evaluated by multiple redocking experiments. The results demonstrate that PSOs were more suitable than Lamarckian genetic algorithm (LGA). Among all of the PSO variants, FIPS takes precedence over others. Compared with the four state-of-art docking methods-GOLD, DOCK, FlexX and AutoDock with LGA, AutoDock cooperated with FIPS is more accurate. Thus, FIPS is an efficient PSO variant which has promising prospects that can be expected in the application to virtual screening.
GLOBAL DYNAMICS OF A DIFFERENTIAL SUSCEPTIBILITY MODEL
Authors: RAZVAN M. R. , YASAMAN S.
Published: August 2011

An SIS epidemiological model in a population of varying size with two dissimilar groups of susceptible individuals has been analyzed. We prove that all the solutions tend to the equilibria of the system. Then we use the Poincaré Index theorem to determine the number of the rest points and their stability properties. It has been shown that bistability occurs for suitable values of the involved parameters. We use the perturbations of the pitchfork bifurcation points to give examples of all possible dynamics of the system. Some numerical examples of bistability and hysteresis behavior of the system has been also provided.
Marked Mydriasis and Neuritis Nervi Optici Associated with Galactorrhea Following Citalopram Treatment: A Case Report and Discussion
Authors: Koch Horst J. , Zellmer Heike
Published: August 2011

We report the case of a 25-year-old women suffering from major depression who was treated with citalopram for several weeks with doses between 20 mg and 60 mg. She gradually developed marked mydriasis within 2 months after treatment and subsequently neuritis nervi optici. Moreover, abrupt galactorrhea occurred after 2 months of treatment. All neuro-ophthalmological, neurophysiological, clinical laboratory, and neuroradiological diagnostic efforts did not reveal an underlying organic pathophysiology. The ocular symptoms disappeared rapidly after the discontinuation of citalopram and pulse therapy with methyl-prednisolone. However, galactorrhea persisted for a few weeks necessitating treatment with bromocriptine.
How Family Forest Owners Consider Timber Harvesting, Land Sale, and Conservation Easement Decisions: Insights from Massachusetts, USA
Authors: Ma Zhao , Kittredge David B.
Published: August 2011

Ten million family forest owners own 35 percent of US forestland. Although one owner's action may be insignificant, many owners' decisions across the landscape and over time can together affect the forest ecosystem. By analyzing survey data from Massachusetts, this paper examines the thought processes of family forest owners when considering timber harvesting, land sale, and conservation easement decisions, all having great potential to shape the future of individual properties and forest landscape. Some factors (e.g., attitudes towards forestland and desire for and experience of cooperation) were important for engaged and unengaged owners, some factors (e.g., attained education level, age, and absenteeism) were irrelevant, and some factors (e.g., acreage and information sources) had mixed effects depending on the decision and landowner engagement level. The results suggest the need to avoid any one-size-fits-all approach, differentiate landowners based on their engagement level, and tailor outreach efforts to address the interests and concerns of particular audiences.
Global Structure of Positive Solutions of a Discrete Problem with Sign‐Changing Weight
Authors: Ma Ruyun , Gao Chenghua , Han Xiaoling , Chen Xiaoqiang
Published: August 2011

Let T > 5 be an integer, 𝕋 = {1, 2, …, T}. We are concerned with the global structure
of positive solutions set of the discrete second‐order boundary value problems
Δ2u(t − 1) + rm(t)f(u(t)) = 0,  t ∈ 𝕋,   u(0) = u(T + 1) = 0,
where r ∈ ℝ is a parameter, m : 𝕋 → ℝ changes its sign and m(t) ≠ 0 for  t ∈ 𝕋.
Dispersion Engineered Silicon Nanocrystal Slot Waveguides for Soliton Ultrafast Optical Processing
Authors: De Leonardis Francesco , Passaro Vittorio M. N.
Published: August 2011

We propose, for the first time to our knowledge, the theoretical investigation of silicon nanocrystals-based sandwiched slot waveguides which are dispersion-engineered for exciting optical solitons inside very short structures (only 1.2 mm long). Several parametric simulations have been performed by means of finite element method in order to individuate the best waveguide cross-sections for achieving an anomalous dispersion regime around 1550 nm.
Nonlinear Autoregressive Conditional Duration Models for Traffic Congestion Estimation
Authors: Vlahogianni Eleni I. , Karlaftis Matthew G. , Kepaptsoglou Konstantinos
Published: August 2011

The considerable impact of congestion on transportation networks is reflected by the vast amount of research papers dedicated to congestion identification, modeling, and alleviation. Despite this, the statistical characteristics of congestion, and particularly of its duration, have not been systematically studied, regardless of the fact that they can offer significant insights on its formation, effects and alleviation. We extend previous research by proposing the autoregressive conditional duration (ACD) approach for modeling congestion duration in urban signalized arterials. Results based on data from a signalized arterial indicate that a multiregime nonlinear ACD model best describes the observed congestion duration data while when it lasts longer than 18 minutes, traffic exhibits persistence and slow recovery rate.
Evaluation of Genotype Diversity in Oat Germplasm and Definition of Ideotypes Adapted to the Mediterranean Environment
Authors: Iannucci Anna , Codianni Pasquale , Cattivelli Luigi
Published: August 2011

Oat (Avena sativaL.) is a cereal species widely used for human food and livestock feed. It is rich in primary metabolites (e.g., protein, carbohydrate, and fibre) as well as in many secondary compounds (e.g., fructo-oligosaccharides). A germplasm evaluation was carried out to determine the genetic diversity, using univariate and multivariate analyses, and to define an oat ideotype for grain and fodder production adapted to the Mediterranean environment. A total of 109 genotypes were studied under field conditions in Foggia (southern Italy) over two growing seasons (2008-2009 and 2009-2010). All of the accessions were characterised according to 13 bioagronomic traits. Accessions were very different for these evaluated traits, with wide variabilities found particularly for seed yield and fructo-oligosaccharide concentration (CV = 37%). Principal component analysis showed that the first six axes accounted for 81% of the variability. Productivity characteristics and heading time were the major sources of diversity among these oat populations. Clustering entries identified nine groups based on their morphological and agronomic properties. The relationships found among traits can help to determine which groups of genotypes are better adapted to specific environmental conditions and to identify ideotypes for developing varieties for different purposes such as for food or forage.
Health-Related Conditions and Depression in Elderly Mexican American and Non-Hispanic White Residents of a United States-Mexico Border County: Moderating Effects of Educational Attainment
Authors: Briones David F. , Heller Peter L. , Carcoba Luis M. , Weisman Henry W. , Ledger Elizabeth M. , Escamilla Michael A.
Published: August 2011

We investigated the prevalence of “high” levels of depressive symptomatology and 13 health-related medical conditions in elderly Mexican American (MA) and non-Hispanic white (NHW) residents of El Paso County, Texas. We analyzed the extent to which depressive symptoms in this population are associated with these conditions. Elderly MA residents possessed a higher prevalence of current depression, a relatively unique health-related condition profile, and were more likely to experience a set of conditions that impede participation in daily life—conditions that we found to be strongly associated with high depressive symptomatology in the elderly. After adjusting for educational attainment, using multiple regression analyses, depression was not associated with ethnicity and only six of the health related conditions showed significant differences between MA and NHW subjects. We believe these results provide an important insight into the mechanism of health-related conditions and depressive symptomatology in a large sample of elderly MAs; and how conditions typically attributed to MA ethnicity may in actuality be an artifact of socioeconomic status variables such as educational-attainment.
The European Medicines Agency: An Overview of Its Mission, Responsibilities, and Recent Initiatives in Cancer Drug Regulation
Authors: Pignatti Francesco , Gravanis Iordanis , Herold Ralf , Vamvakas Spiros , Jonsson Bertil , Marty Michel
Published: August 2011

The European Medicines Agency (EMA) is responsible for the scientific evaluation of medicines developed by pharmaceutical companies for use in the European Union (EU). Since 2005, the agency has become responsible for the approval of all new oncology drugs in the EU. In this article we describe the mission, role, and responsibilities of the EMA, and provide a brief summary of recent initiatives related to cancer drug regulation. The EMA recently published its Road Map to 2015. Over the next 5 years, the agency aims to continue to stimulate drug development in areas of unmet medical needs. Concerning drug safety, one of the priorities over the next few years will be to establish a more proactive approach in ensuring patient safety. This is the result of new EU legislation coming into force in 2012 that will strengthen the way the safety of medicines for human use is monitored in the EU. In terms of its general operation, the agency is committed to increased openness and transparency, and to build on its interactions with stakeholders, including members of academia, health care professionals, patients, and health technology assessment bodies. The agency recently created an oncology working party to expand the current guideline for the development and evaluation of cancer drugs. The guideline focuses on both exploratory and confirmatory studies for different types of agents. The current revision will address a number of topics, including the use of biomarkers as an integrated part of drug development and the use of progression-free survival as a primary endpoint in registration trials. Clin Cancer Res; 17(16); 5220–5. ©2011 AACR.
Epigenetic Epidemiology: The Rebirth of Soft Inheritance
Authors: Hanson Mark A. , Low Felicia M. , Gluckman Peter D.
Published: August 2011

Non-communicable diseases (NCDs), such as cardiovascular disease and type 2 diabetes, constitute the main cause of death worldwide. Eighty percent of these deaths occur in low- and middle-income countries, especially as these countries undergo socio-economic improvement following reductions in the burden of infectious disease. The World Health Organization predicts a substantial increase in the incidence of NCDs over the next decade globally. NCDs are generally preventable, but current approaches are clearly inadequate. New initiatives are needed to implement such prevention, and there needs to be greater recognition that early-life interventions are likely to be the most efficacious. Devising appropriate prevention strategies necessitates an understanding of how the developmental environment influences risk. Progress in this field has been slow due to an excessive emphasis on fixed genomic variations (hard inheritance) as the major determinants of disease susceptibility. However, new evidence demonstrates the much greater importance of early-life developmental factors, involving epigenetic processes and ‘soft’ inheritance in modulating an individual’s vulnerability to NCD. This also offers opportunities for novel epigenetic biomarkers of risk or interventions targeting epigenetic pathways to be devised for use in early life. This may pave the way to much more effective, customised interventions to promote health across the life course.
The Incidence and Survival of Acute de novo Leukemias in Estonia and in a Well-Defined Region of Western Sweden during 1997–2001: A Survey of Patients Aged 16–64 Years
Authors: Wennström Lovisa , Safai-Kutti Soodabeh , Stockelberg Dick , Holmberg Erik , Palk Katrin , Varik Mirja , Viigimaa Iige , Vaht Krista , Luik Ene , Everaus Hele , Kutti Jack
Published: August 2011

Background: In a recent retrospective study, we investigated the incidence and survival of de novo acute leukemia (AL) patients aged 16–64 years over three 5-year periods (1982–1996) in Estonia and in the Western Swedish Health Care Region. The incidence rates were similar in the two countries, but the survival data were highly different. Thus, relative survival at 5 years for de novo AL patients in Estonia was virtually negligible, whereas the corresponding figures for the Swedish patients increased from 20.3 to 38.9% during the study period. Aim: To prospectively compare the results for incidence and outcome of de novo AL between the two countries during 1997–2001. Results: Incidence rates for de novo AL were lower in Estonia than in western Sweden but not significantly so. However, the survival for de novo AL patients in Estonia had improved considerably, with the relative survival at 5 years being 16.4%; such improvement was particularly seen in acute myeloid leukemia patients. For the Swedish patients, no change in survival was recorded. Conclusion: In Estonia, a remarkable improvement in outcome for young de novo AL patients was seen after 1996. Nevertheless, relative survival for the Estonian patients had still not reached the levels found in the Swedish cohort.
Clinical Course of Patients with Familial Early-Onset Alzheimer’s Disease Potentially Lacking Senile Plaques Bearing the E693Δ Mutation in Amyloid Precursor Protein
Authors: Shimada Hiroyuki , Ataka Suzuka , Tomiyama Takami , Takechi Hajime , Mori Hiroshi , Miki Takami
Published: August 2011

Background/Aims: Oligomeric amyloid β (Aβ) is currently considered to induce Alzheimer’s disease (AD). We examined 2 patients with familial AD who possessed the Osaka (E693Δ) mutation in amyloid precursor protein. To the best of our knowledge, these patients are the first AD cases presumably affected with Aβ oligomers in the absence of senile plaques, and they support the Aβ oligomer hypothesis. Methods: We evaluated the clinical course, neuropsychological data, cerebrospinal fluid biomarker levels, magnetic resonance imaging (MRI) scans, fluorodeoxyglucose-positron emission tomography (PET) scans, and Pittsburgh compound B (PiB)-PET images of these patients. Results: In the early stages, these patients developed memory disturbances in a similar rate to patients with sporadic AD. Despite their memory disturbances, both patients showed only limited brain atrophy on MRI and little amyloid accumulation on PiB-PET. Subsequent to the development of memory disturbances, both patients suffered from motor dysfunction, probably due to cerebellar ataxia, and, within a few years, the patients fell into an apallic state. Conclusions: Familial AD patients with Osaka (E693Δ) mutation show severe dementia, cerebellar ataxia, and gait disturbances.
Unstable QT Interval Dynamics Precedes Ventricular Tachycardia Onset in Patients With Acute Myocardial Infarction
Authors: Chen Xiaozhong , Hu Yuxuan , Fetics Barry J. , Berger Ronald D. , Trayanova Natalia A.
Published: August 2011

Background—

Instability in ventricular repolarization in the presence of premature activations (PA) plays an important role in arrhythmogenesis. However, such instability cannot be detected clinically. This study developed a methodology for detecting QT interval (QTI) dynamics instability from the ECG and explored the contribution of PA and QTI instability to ventricular tachycardia (VT) onset.

Methods and Results—

To examine the contribution of PAs and QTI instability to VT onset, ECGs of 24 patients with acute myocardial infarction, 12 of whom had sustained VT (VT) and 12 nonsustained VT (NSVT), were used. From each patient ECG, 2 10-minute-long ECG recordings were extracted, 1 right before VT onset (onset epoch) and 1 at least 1 hour before it (control epoch). To ascertain how PA affects QTI dynamics stability, pseudo-ECGs were calculated from an MRI-based human ventricular model. Clinical and pseudo-ECGs were subdivided into 1-minute recordings (minECGs). QTI dynamics stability of each minECG was assessed with a novel approach. Frequency of PAs (f
PA
) and the number of minECGs with unstable QTI dynamics (N
us
) were determined for each patient. In the VT group, f
PA
and N
us
of the onset epoch were larger than in control. Positive regression relationships between f
PA
and N
us
were identified in both groups. The simulations showed that both f
PA
and the PA degree of prematurity contribute to QTI dynamics instability.

Conclusions—

Increased PA frequency and QTI dynamics instability precede VT onset in patients with acute myocardial infarction, as determined by novel methodology for detecting instability in QTI dynamics from clinical ECGs.
Metamorphosis, Transfiguration, and the Body
Authors: Walsh Richard , Aichele George
Published: August 2011

This essay examines the recent movies Avatar and District 9 in conjunction with the so-called "transfiguration stories" of Matt. 17, Mark 9, and Luke 9. It explores the difference between "transfiguration" and "metamorphosis" in these stories, and questions the avoidance of the latter term in English translations of the New Testament, as well as theological implications of the preference for "transfiguration." This tendency is already observable in the ideological dimensions of the New Testament. That the net effect of this translation preference is to obscure monstrous changes to the body of Jesus is made clear through contrast with the movies, and with Franz Kafka's story, "The Metamorphosis."