bluuebunny/crossref_metadata_2025 huggingface dataset:
Heating effect of electron beam bombardment
Authors: Liu Min , Xu Leying , Lin Xuzhi
Published: July 2010

The effect of heat in a target bombarded by an electron beam with certain energy was studied. A physical model was proposed according to the pattern of electron scattering, separately for a bulk specimen in electron probe microanalysis and a thin‐film specimen in transmission electron microscopy. Then formulas of rising temperature were deduced for these two events. The results of a melting experiment of Bi‐coating on glass and crystallizing of amorphous Fe78Si12B10 film under electron beam bombardment confirmed the proposed model.
A new method of compositional image formation by a four‐element backscattered electron detector in an SEM
Authors: Mityukhlyaev V. B. , Dyukov V. G.
Published: July 2010

A special mixing procedure for signals from a four element backscattered electron (BSE) detector is proposed for compositional image formation when a sample with a rough surface is examined by a scanning electron microscope (SEM). The new method allows appreciable suppression of the influence of the sample surface topography in a compositional mode for take‐off angles less than about 30°, relative to the microscope axis. The theoretical approach based on the analysis of BSE angular distribution is compared with the experiment. The mixing procedure uses a dimensionless parameter, which depends mainly on take‐off angle. Photographs of the Ge‐Zn structure with its rough surface were taken in conventional and proposed compositional modes for take‐off angle 11° and electron energy 20 keV and show a considerable suppression of the topographic effect when the new method is used.
Electroless plating—A new technique for the preparation of hard tissue specimens for scanning electron microscopy
Authors: Kingsmill Virginia , Boyde Alan , Kathirgamanathan Poopathy
Published: July 2010

Specimens with complicated, intricate three‐dimensional structures, which are otherwise difficult to coat adequately by conventional means (sputter or evaporative coating) for scanning electron microscopy, can quickly and simply be rendered conductive by electroless plating. The technique can be recommended only when studying specimens at low magnification because fine detail may be lost.
Polytype transformations in SiC‐epitaxial layers: The color cathodoluminescence‐sem studies
Authors: Saparin G. V. , Obyden S. K. , Mokhov E. N. , Roenkov A. D. , Ahmedov B. A.
Published: July 2010

The polytype transformation in SiC‐epitaxial layers grown by the sublimation “sandwich method” have been studied by means of a real color SEM cathodoluminescence (CL) technique. The variation of polytypes grown on 6H‐, 4H‐, 15R‐, and 21R‐polytype substrates is demonstrated. Different spectral composition of local CL emission is observed on smooth and profiled substrate surfaces. The double polytype transformation effect was fixed. The nature of the polytype transformation in SiC epitaxial layers is discussed.
The attachment of mineralised tissues to coverslips for observing dynamic events by confocal microscopy
Authors: Griffiths Brigitte M. , Watson T. F.
Published: July 2010

In confocal scanning optical fluorescence microscopy, using high‐aperture oil immersion lenses, the best images are obtained for focus planes immediately under the coverslip, or under a continuation of the coverslip with a medium with the same, high refractive index. Therefore placing the coverslip with a layer of oil underneath it is an advantage if the sample will allow it. If experimental manipulations that can displace the coverslip are involved, —for example, attempts to make dynamic observation of fluid flow—the coverslip is best cemented to the sample with a high‐index material. This report describes the use of adhesive systems developed for restorative dentistry to achieve a durable attachment of dental tissues to microscope coverslips. The technique described in this paper has been used for monitoring real‐time fluid movement in dentine. The samples were examined with a high‐frame‐rate confocal microscope (a tandem scanning microscope). The adhesive technology also could be utilised in the microscopic preparation of other porous translucent materials.
Computation of polar angle of collisions from partial elastic mott cross‐sections
Authors: Drouin Dominique , Gauvin Raynald , Joy David C.
Published: July 2010

A formula is presented for computing the polar angle of collisions from partial elastic Mott cross‐sections. It will be useful in Monte Carlo simulations of electrons' trajectories in solids and is based on the Newbury and Myklebust (1981) expression. It also is valid for all energy ranging from 0.1 to 30 keV. Also given is the tabulation of the constants of this formula to compute polar angles of collisions for the first 94 elements of the periodic table. The constants of this formula have been obtained by the numerical integration of the values of partial Mott cross‐sections computed by Czyżewski et al. (1990) using Thomas‐Fermi‐Dirac atomic potentials for atomic numbers >54 and Hartree‐fock potential for atomic numbers <55.
Quantitation of SEM EBIC and CL signals using Monte Carlo electron‐trajectory simulations
Authors: Holt D. B. , Napchan E.
Published: July 2010

A microcomputer Monte Carlo program simulates electron trajectories in solids and describes the distribution of energy deposited throughout the energy‐dissipation (electron‐hole pair generation) volume. From this distribution, the electron‐beam‐induced current or cathodoluminescence signal that will be generated can be calculated for the chosen beam conditions in a multilayer specimen of any geometry and compositions. The use of this program is illustrated by applications (1) to simulate curves of cathodoluminescence intensity versus beam energy for fitting to experimental data to evaluate materials and device parameters, (2) to calculate the energy deposited in each layer of a HEMT structure in which electron‐beam‐induced current studies are in progress, and (3) to the simulation of defect contrast linescan profiles which are compared to experimental observations.
Charge‐sensitive secondary electron imaging of diamond microstructures
Authors: Harker A. B. , Howitt D. G. , DeNatale J. F. , Flintoff J. F.
Published: July 2010

The surface orientation and detailed defect microstructure of polycrystalline diamond can be observed in a scanning electron microscope through local changes in the surface conductivity. The electron contrast in uncoated samples is straightforward to distinguish when the rms surface roughness is less than about 2 nm. This degree of smoothness occurs on some of the faceted surfaces of individual diamond grains but can also be achieved by polishing. The contrast, observable only in the secondary electron imaging mode, shows a strong dependence on both beam voltage and current. It is postulated that the contrast is produced solely by the differential rate at which the electron beam‐induced charge can be locally dissipated through crystalline defects and grain boundaries in the otherwise highly nonconductive diamond matrix. The appearance of the charge‐related contrast requires that highly connected pathways exist between the crystalline defects and the high‐angle grain boundaries.
SEM investigations of etched heavy ion tracks
Authors: Vetter Johann
Published: July 2010

It is shown that the scanning electron microscope (SEM) is an invaluable tool for the investigation of etched ion tracks, particularly in the submicron range. The SEM makes it possible to measure doses with track detectors two orders of magnitude higher than when they are measured by a light microscope. Furthermore, the SEM is used for investigation of the etched‐track cross sections over the full length of the channels. Growing of metal needles in the membranes by microgalvanic deposition allows replication of the form of the etched channels. After the membrane is dissolved, the metal needle replicas instead of the membrane can be investigated. It will be shown that the SEM is an important tool for the investigation of etched heavy ion tracks in solids.
Representation of scanning probe images in virtual reality
Authors: Kasas S. , Solletti J. M. , Cargnello R.
Published: July 2010

The visualization of the data obtained with scanning probe microscopes can be improved by the use of virtual reality software which has recently become available commercially. One such software program was applied to images obtained with an atomic force microscope. The mapping capabilities of this new visualization technique as well as the images were quite striking when viewed in virtual reality.
Volume measurements in three‐dimensional microscopy
Authors: Visser T. D. , Oud J. L.
Published: July 2010

A refractive index mismatch between the oil immersion and the microscopic object can lead to a severe over‐estimation of the object's size. The cause of this effect is explained and a simple calibration method to compensate for its occurrence is presented. A practical example is discussed. The analysis applies to both conventional three‐dimensional, and confocal microscopy.
The boundary fitted coordinate method to improve the numerical analysis of electron optical systems
Authors: Khursheed A.
Published: July 2010

This paper illustrates some of the advantages of using the boundary fitted coordinate technique in the numerical simulation of electron‐optical systems. The boundary fitted coordinate technique can be used as an automatic mesh generator for the finite‐element solution of field distributions, while at the same time allowing for the possibility of high order inter‐polation on the mesh, typically required for the accurate plotting of electron trajectory paths. For the finite difference method of solving field distributions, the boundary fitted coordinate method can generate regular meshes, which fit curved shaped boundaries.
Identification of fenestrated capillary segments in microvascular corrosion casts of the rat exocrine pancreas
Authors: Aharinejad Seyedhossein , Böck Peter
Published: July 2010

The capillary bed of the rat exocrine pancreas was studied by scanning and transmission electron microscopy of corrosion casts and tissue sections. Two types of capillaries were distinguished in corrosion casts. First, there were straight capillaries of relatively constant width (mean diameter 4.79±0.87 μm), which were characterized by numerous circular constrictions on their surface. About 37% of the capillaries belonged to this type. Second, there were undulating capillaries which showed smooth surfaced eccentric dilatations defined by similar surface constrictions. The bulging areas measured 8.43 ± 1.33 μm, the constrictions next to the bulges figured for 6.45 ± 1.53 μm. About 63% of the capillaries belonged to the second type. Two types of capillaries were also identified in tissue sections. First, there were capillaries with continuous endothelial lining (26% of capillary profiles; mean diameter 5.48 ± 1.67 μm); 27% of their endothelial lining was provided with underlying pericytes. Second, there were capillaries with fenestrated endothelium (64% of capillary profiles; mean diameter 6.16 ± 1.75 μm); 12% of their endothelial lining was accompanied by pericytes. According to frequency and dimension of these two types of capillaries, we conclude that bulged and undulating capillary casts correspond to fenestrated capillaries and straight capillary casts of constant width correspond to nonfenestrated capillaries. The frequency of crests on the surface of capillary casts correlates with the different frequency of pericyte processes on fenestrated and nonfenestrated capillaries. It is concluded that pericyte processes beneath the endothelium hold resistance against luminal pressure. Bulging areas of capillary casts correlate with fenestrated areas of endothelial lining, that is, areas which are not reinforced by pericyte processes.
Half‐scan cone‐beam X‐ray microtomography formula
Authors: Wang G. , Liu Y. , Lin T. H. , Cheng P. C.
Published: July 2010

An x‐ray shadow projection microtomographic system using a scannable point source is under development at AMIL‐ARTS, SUNY at Buffalo. To overcome the limitations of the commonly used Feldkamp's cone‐beam reconstruction formula, we have developed a generalized Feldkamp‐type cone‐beam reconstruction formula. In the generalized Feldkamp‐type cone‐beam reconstruction, a scanning locus can be either planar or helix‐like, and a transaxial slice is reconstructed using projection data collected from a 360° angular range (full scan). In this paper, the full‐scan cone‐beam formula is modified to require only projection data of approximate 180° plus two fan‐angles (half scan). First, a half‐scan derivative‐free noncircular fan‐beam reconstruction formula is formulated. Then, a half‐scan cone‐beam reconstruction formula is derived as an extension of the half‐scan fan‐beam reconstruction formula using Feldkamp's procedure. Typical numerical simulation results are given for both half‐scan formulae. Compared with the full‐scan cone‐beam formula, the half‐scan cone‐beam formula reduces the involved angular range of projection data and allows better longitudinal/temporal resolution.
Laser and tandem scanning confocal microscopic studies of rabbit corneal wound healing
Authors: Ichijima Hideji , Jester James V. , Petroll W. Matthew , Cavanagh H. Dwight
Published: July 2010

The process of corneal endothelial wound healing was studied using laser and tandem scanning confocal microscopy (LSCM and TSCM). Following transcorneal freeze (TCF) injury, rabbit corneas were observed using ex vivo LSCM and in vivo TSCM. LSCM revealed the intracellular actin filament organization which, stained with phalloidin‐FITC, in migrating endothelial cells, transformed fibroblast‐like cells, stroma keratocytes, and epithelial cells during wound healing in corneal tissue. The TSCM provided sequential spatial observation of morphologic changes from endothelium to epithelium of the cornea during in vivo cellular repair of wound healing noninvasively on the same cornea without animal sacrifice. Ex vivo LSCM supported the morphologic analysis of the in vivo TSCM observations.
High temporal and spatial resolution studies of bone cells using real‐time confocal reflection microscopy
Authors: Boyde A. , Vesely P. , Gray C. , Jones S. J.
Published: July 2010

Chick and rat bone‐derived cells were mounted in sealed coverslip‐covered chambers; individual osteoclasts (but also osteoblasts) were selected and studied at 37°C using three different types of high‐speed scanning confocal microscopes: (1) A Noran Tandem Scanning Microscope (TSM) was used with a low light level, cooled CCD camera for image transfer to a Noran TN8502 frame store‐based image analysing computer to make time lapse movie sequences using 0.1 s exposure periods, thus losing some of the advantage of the high frame rate of the TSM. Rapid focus adjustment using computer controlled piezo drivers permitted two or more focus planes to be imaged sequentially: thus (with additional light‐source shuttering) the reflection confocal image could be alternated with the phase contrast image at a different focus. Individual cells were followed for up to 5 days, suggesting no significant irradiation problem. (2) Exceptional temporal and spatial resolution is available in video rate laser confocal scanning microscopes (VRCSLMs). We used the Noran Odyssey unitary beam VRCSLM with an argon ion laser at 488 nm and acousto‐optic deflection (AOD) on the line axis: this instrument is truly and adjustably confocal in the reflection mode. (3) We also used the Lasertec 1LM11 line scan instrument, with an He‐Ne laser at 633 nm, and AOD for the frame scan. We discuss the technical problems and merits of the different approaches. The VRCSLMs documented rapid, real‐time oscillatory motion: all the methods used show rapid net movement of organelles within bone cells. The interference reflection mode gives particularly strong contrasts in confocal instruments. Phase contrast and other interference methods used in the microscopy of living cells can be used simultaneously in the TSM.
Confocal microscopy of corneal penetration by tarantula hairs
Authors: Kaufman S. C. , Chew S. J. , Capps S. C. , Beuerman R. W.
Published: July 2010

In vivo identification of foreign bodies in the cornea may be impossible if the size and/or location precludes visualization by slit lamp biomicroscopy, which has an upper limit of magnification of 50x. These limitations became obvious when we attempted to identify the offending material in the inflamed eye of a patient who complained of foreign body sensation after contact with a pet tarantula As a model of this clinical situation, we used a newly developed tandem scanning confocal microscope to observe and to photograph tarantula hairs as they penetrated the corneal stroma and endothelium and entered the anterior chamber in rabbit eyes. We found that, experimentally, the hairs penetrated the ocular tissues apparently without inciting inflammation or causing fibrosis. The instrument we used‐ a prototype with a Nipkow disk from Noran, Inc. (Middleton, Wis.) and a 25/0.8 na glycerin immersion lens (Plan‐Neofluor, Zeiss)–provides magnifications of 100–500X, real‐time viewing in vivo, optical sectioning, contrast control, high resolution, processing through image analysis systems, and video and hard copy output. We believe that confocal microscopy offers a new approach to the identification and localization of foreign bodies in the anterior segment, as well as to the visualization and diagnosis of ocular diseases, including bacterial, fungal, and other parasitic invasions, in the human eye.
In vivo observation of the human tear film by tandem scanning confocal microscopy
Authors: Mathers William D. , Daley Thomas E.
Published: July 2010

A new method for observing normal and pathologic states of the human tear film using tandem scanning confocal microscopy is presented. The confocal microscope is configured with a horizontal light path, a 10 x dry objective, and an image‐intensified camera for collecting images at a magnification of approximately 150x. The advantages of confocal microscopy can be used to collect reflected images of the human tear film with improved detail and resolution.
Near fields of periodic gratings calculated using rigorous electromagnetic theory
Authors: Körner T. O. , Sheridan J. T.
Published: July 2010

Rigorous electromagnetic theory (REMT) can be used to calculate the fields above dielectric and metallic gratings. In this paper, by including evanescent orders, the near fields are presented. The Legendre method is used to carry out these calculations. In this method the fields in each of the homogeneous sections along a grating period are approximated by Legendre polynomials. This method is an exact eigenfunction method in which the eigenvalues are found using simple matrix eigenvalue/eigenvector algorithms. By carefully dealing with the boundary conditions, extremely deep and highly conducting gratings can be examined. The convergence of the diffraction orders and nonimplicit power conservation are used to test the results. Contour plots showing the absolute value of the E‐field near gratings for a large range of periods, depths, duty cycles, angles of incidence, and surface profiles are presented.
Highly controllable fabrication of fiber probe for photon scanning tunneling microscope
Authors: Pangaribuan Togar , Jiang Shudong , Ohtsu Motoichi
Published: July 2010

A selective chemical etching was used to fabricate fiber probes for the photon scanning tunneling microscope (PSTM). The cladding diameter of the fiber probe was controlled by varying the first‐step etching time. The cone angle of the fiber probe tip was controlled by varying the doping ratio of the fiber and the composition of the etching solution. A cladding diameter of 8 μm and a tip diameter of about 3 nm were fabricated. The smallest cone angle was 14°.
Analysis of submicron particles by scanning electron microscopy‐energy‐dispersive X‐ray spectrometry—accuracy of size measurement
Authors: Mitsche S. , Poelt P. , Wagner J.
Published: July 2010

Scanning electron microscopy combined with energy‐dispersive x‐ray spectrometry (SEM‐EDXS) is widely used for particle analysis. In the case of submicron particles, especially for particles that are smaller than 300 nm, the measured particle size is influenced by specimen preparation, SEM operating parameters, the mean atomic number of the particles, and the threshold value used for binarization. The use of uncoated particles on a conductive substrate and image acquisition using an in‐lens detector are recommended for precise morphologic results in this size range.
Contactless optical scanning of fingerprints with 180° view
Authors: Palma J. , Liessner C. , Mil'Shtein S.
Published: July 2010

Fingerprint recognition technology is an integral part of criminal investigations. It is the basis for the design of numerous security systems in both the private and public sectors. In a recent study emulating the fingerprinting procedure with widely used optical scanners, it was found that, on average, the distance between ridges decreases about 20% when a finger is positioned on a scanner. Using calibrated silicon pressure sensors, the authors scanned the distribution of pressure across a finger, pixel by pixel, and also generated maps of the average pressure distribution during fingerprinting. Controlled loading of a finger demonstrated that it is impossible to reproduce the same distribution of pressure across a given finger during repeated fingerprinting procedures. Based on this study, a novel method of scanning the fingerprint with more than a 180° view was developed. Using a camera rotated around the finger, small slices of the entire image of the finger were acquired. Equal sized slices of the image were processed with a special program assembling a more than 180° view of the finger. Comparison of two images of the same fingerprint, namely the registered and actual images, could be performed by a new algorithm based on the symmetry of the correlation function. The novel method is the first contactless optical scanning technique to view 180° of a fingerprint without moving the finger. In a machine which is under design, it is expected that the full view of one finger would be acquired in about a second.
Differential interference contrast and confocal reflectance imaging of collagen organization in three‐dimensional matrices
Authors: Petroll W. Matthew
Published: July 2010

The remodeling of extracellular matrices by cells plays a defining role in developmental morphogenesis and wound healing as well as in tissue engineering. Three‐dimensional (3‐D) type I collagen matrices have been used extensively as an in vitro model for studying cell‐induced matrix reorganization at the macroscopic level. However, few studies have directly assessed the process of 3‐D extracellular matrix (ECM) remodeling at the cellular and subcellular level. In this study, we directly compare two imaging modalities for both quantitative and qualitative imaging of 3‐D collagen organization in vitro: differential interference contrast (DIC) and confocal reflectance imaging. The results demonstrate that two‐dimensional (2‐D) DIC images allow visualization of the same population of collagen fibrils as observed in 2‐D confocal reflectance images. Thus, DIC can be used for qualitative assessment of fibril organization, as well as tracking of fibril movement in sequential time‐lapse 2‐D images. However, we also found that quantitative techniques that can be applied to confocal reflectance images, such as Fourier transform analysis, give different results when applied to DIC images. Furthermore, common techniques used for 3‐D visualization and reconstruction of confocal reflectance datasets are not generally applicable to DIC. Overall, obtaining a complete understanding of cell‐matrix mechanical interactions will likely require a combination of both wide‐field DIC imaging to study rapid changes in ECM deformation which can occur within minutes, and confocal reflectance imaging to assess more gradual changes in cell‐induced compaction and alignment of ECM which occur over a longer time course.
Spectral characteristics of autofluorescence and second harmonic generation from ex vivo human skin induced by femtosecond laser and visible lasers
Authors: Chen Jianxin , Zhuo Shuangmu , Luo Tianshu , Jiang Xingshan , Zhao Jingjun
Published: July 2010

The spectral properties of one‐photon, two‐photon excited autofluorescence and second harmonic generation (SHG) from ex vivo human skin induced by a femtosecond (fs) laser and three visible lasers in backscattering geometry are systematically investigated. Our experimental results indicate that peak position of autofluorescence spectra from the dermis and epidermis shift toward long wavelengths, and the fluorescent intensity decreases when the excitation wavelength increases due to an effect of the excitation wavelength on autofluorescence signals. However, the intensity of the SHG signal in collagen has the maximal value of 800 nm excitation wavelength. This may be the result that the energy of the SHG signal is in resonance with an electronic absorption band. The two‐photon excited autofluorescence and SHG intensity all obey a quadratical dependence on the excitation power. Compared with the two‐photon excited fluorescence and SHG, the one‐photon excited fluorescence in the dermis and epidermis exhibits different spectral characteristics. The investigation of the spectral characteristics of autofluorescence and SHG from ex vivo human skin can provide new insights into morphologic structures and biochemical components of tissues, which are vital for improving the application of laser‐induced autofluorescence and SHG spectroscopy technique for noninvasive in vivo tissue diagnostics.
A software modeling approach for the design and analysis of cooperative optimization systems
Authors: Amo Ignacio J. G. del , Pelta David A. , Masegosa Antonio D. , Verdegay Jose L.
Published: July 2010

Optimization problems are ubiquitous in our daily lives and one way to cope with them is using cooperative optimization systems that allow to obtain good enough, fast enough, and cheap enough solutions. From a practical point of view, the design and the analysis of such systems are complex tasks. In this work, an integrated system (DACOS) for helping in the design and analysis of cooperative, centralized optimization systems is presented. Also, the methodology used for the creation of DACOS (mainly, the use of software modeling) is described in detail. This may also be useful for researchers who want to build up their own system for their particular needs. DACOS has been developed using the Eclipse developing framework, which, among other advantages, is also able to automatically generate source code. Finally, a practical case of use is presented: the application of DACOS to the configuration and analysis of a cooperative strategy on a location problem. Copyright © 2010 John Wiley & Sons, Ltd.
Semi‐automated system for measurement of nuchal translucency thickness
Authors: Moratalla J. , Pintoffl K. , Minekawa R. , Lachmann R. , Wright D. , Nicolaides K. H.
Published: July 2010

Objective

To estimate intersonographer and intrasonographer variance components of fetal nuchal translucency (NT) thickness measurement using the traditional manual approach and a new semi‐automated system.

Methods

A semi‐automated method was developed for measurement of the NT. In this method, the operator places an adjustable box over the relevant area at the back of the fetal neck. The system draws a line through the center of the nuchal membrane and another line at the edge of the soft tissue overlying the cervical spine. The system then identifies the largest vertical distance between the two lines. The images of 12 fetuses at 11–13 weeks of gestation satisfying the guidelines of The Fetal Medicine Foundation for measurement of NT were selected. They were exported in DICOM format from the ultrasound system, and four versions of each image were stored under different names. The resulting 48 images were presented in random order for electronic assessment. A total of 20 sonographers measured the NT in each set of 48 pictures, twice using the semi‐automated system and twice using the manual system, according to a randomized block design. Within‐ and between‐operator variance components were estimated. Relative biases were assessed by comparing the means from the two methods.

Results

The estimated between‐operator SD using the semi‐automated method was 0.0149 mm compared with 0.109 mm for the manual method. The respective within‐operator SD values were 0.05 mm and 0.126 mm. The intraclass correlation coefficients for different sonographers measuring the same images were 0.98 and 0.85 for the semi‐automated method and the manual method, respectively.

Conclusion

The measurement of fetal NT is more reliable when a semi‐automatic approach is used rather than the traditional manual method. Copyright © 2010 ISUOG. Published by John Wiley & Sons, Ltd.
Longitudinal changes in uterine, umbilical and fetal cerebral Doppler indices in late‐onset small‐for‐gestational age fetuses
Authors: Oros D. , Figueras F. , Cruz‐Martinez R. , Meler E. , Munmany M. , Gratacos E.
Published: July 2010

Objectives

To determine the longitudinal trends and rates of conversion of normal to abnormal uterine (UtA), umbilical (UA) and middle cerebral artery (MCA) Doppler velocimetry throughout the third trimester in late‐onset small‐for‐gestational‐age (SGA) fetuses.

Methods

UtA, UA and MCA Doppler velocimetry was serially performed in a cohort of singleton consecutive late‐onset SGA fetuses with normal Doppler values at diagnosis. The rate of conversion of normal to abnormal Doppler values was evaluated by survival analysis. Longitudinal trends were modeled by means of multilevel analysis.

Results

A total of 616 scans were performed on 171 SGA fetuses. Mean gestational age at inclusion and at delivery was 34.1 (SD 1.6) and 38.7 (SD 1.7) weeks, respectively. The proportions of abnormal UtA (2.3 vs. 4.1%) and UA (2.3 vs. 2.9%) pulsatility index (PI) were not significantly different between 37 weeks and before delivery. On the other hand, the proportions of abnormal MCA‐PI (4.1 vs. 13.5%) and cerebroplacental ratio (CPR) (7 vs. 22.8%) were significantly different between these two examinations. The remaining proportion of cases with normal UtA‐, UA‐ and MCA‐PIs and CPR at 40 weeks were 98.6, 94.5, 85 and 49.6%, respectively. Whereas a slight increasing trend was observed for the UtA‐PI (β = 0.002) and UA‐PI (β = 0.01), MCA‐PI (β = 0.044) and CPR (β = 0.124) showed a progressive decrease until delivery.

Conclusions

Late‐onset SGA fetuses with normal Doppler velocimetry upon diagnosis show progression from 37 weeks' gestation with worsening CPR followed by a decrease in MCA‐PI. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Implications of resting eggs of zooplankton for the paradox of enrichment
Authors: Nakazawa Takefumi , Kuwamura Masataka , Yamamura Norio
Published: July 2010

In this study, we numerically investigated to what extent introducing resting‐egg dynamics would stabilize simple Daphnia–algae consumer–resource models. In the models, the density of viable resting eggs was explicitly expressed, and we assumed that zooplankton produced resting eggs seasonally or in response to food deficiency and that resting eggs hatched seasonally. The models predicted that, although the paradox of enrichment was not completely resolved (i.e., the system was destabilized by eutrophication), we found the following conditions under which the stabilizing effects of resting eggs would be significantly large: (1) resting eggs are produced seasonally (rather than in response to food deficiency), (2) the annual average allocation ratio to resting eggs is large, and (3) the annual average hatching rate of resting eggs is low. The results suggest that resting‐egg dynamics can significantly reduce the paradox of enrichment within the biologically meaningful parameter space and contribute to the stability of plankton community dynamics.
Synthesis and Evaluation of a New Cationic Surfactant for Oil‐Well Drilling Fluid
Authors: Mahmoud Soad A. , Dardir Mona M.
Published: July 2010

A new additive cationic surfactant for drilling fluid was synthesized by alkylation of coal tar phenol with tetradecyl alcohol; then, the alkyl phenol reacts with formaldehyde and amine to produce the Mannich base product. This product was reacted with sodium chloroacetate to produce the cationic surfactant; the structure of the synthesized surfactant was confirmed by FTIR analysis, evaluation of the prepared surfactant by surface properties such as surface tension, emulsification power, and wetting power. The prepared cationic surfactant showed good results when utilized in the formulation of both oil‐based mud and synthetic‐based mud as the primary emulsifier.
The impact of premenstrual dysphoric disorder among 92 bipolar patients
Authors: Fornaro M. , Perugi G.
Published: July 2010

Objectives

To evaluate the impact of Diagnostic and Statistical Manual for Mental Disorders-Fourth Edition (DSM-IV)-defined premenstrual dysphoric disorder (PMDD) lifetime co-morbidity among 92 bipolar patients.

Method

Ninety-two women with a lifetime diagnosis of DSM-IV-defined Bipolar Disorder (BD) either type I or type II were consecutively enrolled to determine co-morbidity rates with PMDD and associated clinical features. Measures included the Structured Clinical Interview for the DSM-IV Axis I Disorders (SCID-I) and the Clinical Global Impression (CGI) rating scale.

Results

In our sample, 25 (27.2%) patients reported a lifetime history of PMDD according to DSM-IV criteria (PMDD+). PMDD+ reported higher rates of Cyclothymia and BP-II than PMDD− (respectively 72% vs. 36% and 88% vs. 60%). On the contrary, the carbohydrate-craving feature was more represented among PMDD− than PMDD+ (25% vs. 4%). PMDD was also significantly associated with post-partum depression (36% vs. 15%), Obsessive-Compulsive (24% vs. 7.5%) and Body Dysmorphic Disorders (24% vs. 6%). Finally, PMDD+ reported higher total number of Axis I co-morbid disorders than PMDD−.

Conclusions

In our cohort of BD women, PMDD is a frequent co-morbid condition, in particular among patients with BD-II or Cyclothymia. Multiple co-morbidities also represent a clinical variable associated with PMDD. Further perspective studies are necessary to better define the relationships between PMDD and BD.
Mensch und Körper im Museum: Das Deutsche Hygiene-Museum Dresden
Authors: Vogel Klaus
Published: July 2010

Einleitung

Das Deutsche Hygiene-Museum Dresden, dessen Geschichte von tiefen Brüchen gekennzeichnet ist, hat mit der Entwicklung von einer Gesundheitseinrichtung zu einer Kulturinstitution gleichsam einen Perspektivwechsel auf die Themen Mensch und Körper vollzogen. Damit einher gingen eine Aufweitung des inhaltlichen Portfolios sowie ein Paradigmenwechsel in der Bildungs- und Vermittlungsarbeit.
Executive Briefing: Hospital Risk Management: The Second Decade
Authors: Keddy Wayne R. , Johnson Michael W. , McKerrow Wayne
Published: July 2010

Risk management is defined as the systematic process of identifying, evaluating and addressing potential and actual risk. Although introduced to the hospital industry nearly a decade ago, its status in Canadian hospitals remains uncertain, a position that is in sharp contrast to the American situation. Chiefly as a result of the medical malpractice crisis and associated circumstances in the mid-1970s, risk management has emerged as an integral element in the operational activities of American hospitals. The process is a mechanism for self-protection in co-operative, self-insurance arrangements and to secure commercial premium adjustments.

Many trends have been recognized in Canada that would suggest a predisposition toward the proliferation of risk management programs. These indicators include an increase in the number and size of claims against hospitals and physicians, a reduction in the availability of commercial health care insurance, and an increase in alternative insurance arrangements.

Despite these indicators, movement toward risk management by Canadian hospitals has been minimal. A prime reason appears to be lack of financial incentives to stimulate the development of risk management programs. There is also an absence of specific accreditation standards pertaining to such programs.

The case in support of risk management for Canadian hospitals continues to grow. The basic assumptions associated with a program are board, medical and staff support; a concerted effort to recognize and reduce potentially litigious situations and occurrences; and an ability to adapt. The initial steps to develop a risk management program include assessing current risk control activities and implementing structural elements. As well, a program must address its relationship to Quality Assurance activities in the hospital.
Coping with the Intermingling of the Lucid and Confused
Authors: Novick Louis J.
Published: July 2010

The issue of intermingling mentally lucid individuals and confused patients with behaviour problems has been a serious concern for the long-term care facility from the standpoints of the resident, relatives and staff. Efforts at Maimonides Hospital Geriatric Centre in Montreal have included “relationship therapy” (i.e., the relationship between the resident and staff members) to preserve the resident's self-esteem. Also, homogeneous groups of lucid and confused residents have been formed to help each take part in appropriate social activities. Lucid residents also are encouraged to attend weekly meetings with both professional and non-professional staff working on their floor. A staff psychiatrist experienced in psycho-pharmacology has significantly improved the problems created by intermingling these two groups. The psychiatrist also has helped staff reduce the stress caused by intermingling. In addition, staff members meet with relatives before and after admission of applicants to alleviate and discuss their concerns. Nevertheless, Maimonides and other long-term care institutions face the problem of how to reduce the damage of intermingling these two groups of residents.
Key Operating and Financial Ratios for Alberta Hospitals
Authors: Jacobs P. , Hall E.M.
Published: July 2010

Comparative financial and operating ratios in Canadian hospitals are examined to reveal sources of increased efficiency. The study involved 70 Alberta hospitals, which were divided into three groups: teaching hospitals, regional hospitals and smaller rural hospitals. Data were obtained from HS-1 and HS-2 reports. Hospitals across Canada can calculate their own ratios to give them a general idea of how they compare with the hospitals in this report.
French-Language Health Care Services in Ontario
Authors: Deroche Francine C.M.
Published: July 2010

The French Language Services Act, 1986 has had an impact on the provision of health care services in Ontario. The Ontario Ministry of Health's implementation of French-language services is examined in light of three criteria: permanency, quality and accessibility of services. Issues are raised around the measurement and creation of demand for services; the health human resources shortage; health care priorities; what constitutes a high quality service; and the influence of the political and economic climates. The continuing challenge is to provide permanent and accessible high quality French-language health care services within an ailing health care system.
Careers in Health Care Management, Part 1: Attainment, Expectations and Aspirations
Authors: Lemieux-Charles Louise , Murray Michael , Aird Catharine , Barnsley Jan
Published: July 2010

The authors conducted a questionnaire survey of health care managers in Canada to learn more about their careers, work experiences and attitudes; and to determine whether their careers differed by such factors as sector of employment, gender, years of experience, education and family status. Major findings include: in teaching and community hospitals, men are more likely to fill chief executive officer (CEO) positions and women tend to be in middle management positions. More men than women in CEO positions reported incomes in the top range ($105,000). Men in CEO and senior management positions are more likely to be married and have children under 16 years of age living at home. Slightly more women than men were clinicians before becoming managers. Most respondents aspired to CEO or senior management positions. Implications for human resources practices are discussed.
Introducing Data into the Health Policy Process: Developing a Report on the Efficiency of Bed Use in Manitoba
Authors: Roos Noralou P. , Brownell Marni
Published: July 2010

The Manitoba Centre for Health Policy and Evaluation (MCHPE) is a university-based centre funded by the provincial government to provide analyses for use in policy development and management of the health care system. At the government's request, the MCHPE undertook an analysis of bed use in the major hospitals in the province. This article reviews the formulation, execution and delivery of the project to illustrate how health services researchers, administrative data and key actors in the health care system can interact in the policy process.
Continuum: Measuring and Managing the Patient Care Process
Authors: Collins Paul E. , Skafel Jon R. , Atkinson David I. , Jenkins Sandra
Published: July 2010

The authors describe the CONTINUUM project which was initiated in a community hospital to manage the appropriateness, timeliness and acceptability of the patient care process on a concurrent or day-to-day basis. CONTINUUM is a quality and data-driven approach to continuous improvement of the patient care process.

The St. Thomas-Elgin General Hospital researched “appropriateness of care” measurements and adapted their use for the CONTINUUM project. A concurrent care plan evaluation tool is applied to every care every day. This intensity of service (needs-based) strategy is called the ACTIVITY index. Patients are categorized ACTIV (appropriate) or non-ACTIV (perhaps inappropriate). Non-ACTIV patients are further subdivided into various “barriers to care,” from which service, hospital or physician-related factors can be stratified. Practice patterns and hospital resource use are then rapidly identified.

The operational dimensions of the project (bedside, organization and community) are described as well as the inhibitors and enablers of this change process.
Le rôle de l'aumônier lors d'une prise de décision bioéthique
Authors: Simmonds Anne L.
Published: July 2010

Les organismes de soins de santé doivent faire face à des contraintes économiques sérieuses qui menacent de démanteler des services essentiels. Le besoin d'une réforme se fait des plus pressants. La refonte des méthodes administratives pourrait bien être le meilleur remède pour améliorer sensiblement la productivité sans nuire, pour autant, à la qualité et à la portée des services de santé essentiels. Cette refonte met au défi les organismes de soins de santé d'éliminer certaines fonctions ne contribuant pas à une organisation horizontale dans laquelle un nombre moins élevé de dispensateurs de soins assurent une plus grande variété de services de santé. La technologie de l'information a pour but de remplacer les vérifications et les contrôles manuels. La refonte peut aider à implanter des nouveaux modèles de gestion, tels que les soins axés sur les patients, la direction par cas et la gestion des produits et des programmes. Avec le temps, l'amélioration continue de la qualité peut améliorer le produit de la refonte.
Technology Acquisition in Canadian Hospitals: How is it Done, and Where is the Information Coming From?
Authors: Deber Raisa , Wiktorowicz Mary , Leatt Peggy , Champagne François
Published: July 2010

A 1990 nation-wide survey on technology acquisition in Canadian hospitals, based on 509 Anglophone and 55 Francophone hospital questionnaires and 193 hospital equipment request forms, revealed that 53% of capital funds were used to replace existing equipment, with the remainder spent on new purchases. However, very little regional planning was taking place. Most of the institutional acquisition decisions were made by committees, 17% of which were classified as medical staff, 25.1% as administrative, 32.4% as board committees and 22.5% as mixed. Although administration was heavily represented, medical staff were frequently present and nursing was just as likely to have at least minimal representation. However, technical experts usually played a minimal role. This omission, combined with the limited information asked for on equipment request forms and the limited availability and use of technology assessment information, suggests that acquisition decisions in many Canadian hospitals are likely to be based on inadequate information.
Governance of Hospitals in Canada: A Survey of Business Leaders Who Serve as Hospital Trustees
Authors: Brunelle Francis W.H.
Published: July 2010

The Caldwell Partners Amrop International, in the course of conducting executive search, are often in contact with business executives across Canada, many of whom serve as hospital trustees.

Because of the concerns being expressed informally by these trustees, it was decided to conduct a formal survey. The University of Toronto's Department of Health Administration was involved in designing the survey instrument and tabulating the results.

The survey's findings cover many governance issues, such as board size, composition, terms, representation, roles, mergers, evaluation, quality of care, research institutes, fiscal issues and government relations.
Policies and Procedures in the Workplace: How Health Care Organizations Compare
Authors: Loo Robert
Published: July 2010

Many organizations are implementing programs and services to manage the human and economic costs of stress. A mail survey was conducted of 500 randomly selected Canadian organizations having at least 500 employees. The survey tapped four major areas: organizational policies and procedures for managing stress; programs and services offered; perceived benefits and constraints for the organization; and projected future directions in this area. Analyses of returns from 210 organizations — 43 health and 167 non-health — revealed various findings. For example, over half of health care organizations have policies and procedures as opposed to less than half of non-health care organizations. Also, health care organizations place greater emphasis on smoking cessation, weight control programs and on stress management training. Although some Canadian organizations are addressing stress, much more could and should be done, especially by organizations that do not yet recognize the impact of stress on employees and their work performance.
Soutien émotionnel et formation lors d'une restructuration: Plus qu'un palliatif
Authors: Arndt Erika M. , Duchemin Kay F.
Published: July 2010

Cet article illustre l'importance du soutien émotionnel et de la formation offerts aux patients, aux familles, au personnel et aux gestionnaires durant la restructuration entreprise au printemps de 1992 au Queen Elizabeth Hospital de Toronto.

Le Queen Elizabeth Hospital est un établissement de 601 lits, réparti sur deux emplacements qui, tout en ayant vocation d'enseignement et de recherche, dispense des soins de réadaptation et d'entretien de pointe et met en oeuvre des programmes spécialisés de réadaptation médicale ainsi que des services gériatriques, de psychiatrie gériatrique et de soins prolongés.

La restructuration s'est traduite par une réorganisation des services et la fermeture de 82 lits de long séjour, soit une unité de soins dans chacun des deux emplacements, pour compenser un déficit budgétaire escompté de 5,4 millions de dollars. Des restrictions internes n'ont pu ramener ce déficit qu'à 2,8 millions de dollars, rendant ainsi nécessaires des coupures additionnelles.

L'article décrit les activités de soutien informelles et structurées qui ont eu lieu tout au long de cette transition qui a duré deux mois et évoque les sessions de formation dispensées sur une base régulière. Il accorde une attention particulière à la méthodologie et aux raison dictant cette action. Les auteures indiquent également des voies pour que le processus de rationalisation se déroule sans traumatisme.