bluuebunny/crossref_metadata_2025 huggingface dataset:
Aspidistra punctatoides sp. nov. (Ruscaceae) from limestone areas in Guangxi, China
Authors: Lin Chun‐Rui , Liu Yan
Published: April 2011

Aspidistra punctatoides Yan Liu & C. R. Lin (Ruscaceae) is described and illustrated as a new species from limestone areas in southwestern Guangxi, China, near the border with northern Vietnam. It resembles A. punctata Lindl. in leaf size, a campanulate perianth densely covered with purple spots, lobes adaxially with two fleshy keels, and the peltate stigma, but differs by the stigma being adaxially truncate and densely papillate, and by the margin being 3‐ or 4‐lobed with lobes emarginate at apex.
The spectre of Godlessness: Making sense of secularity
Authors: Eipper Chris
Published: April 2011

‘What does it mean to say that we live in a secular age?’ asks the philosopher Charles Taylor from a Christian (Catholic) perspective. This paper critiques key aspects of the way he seeks to answer the question, doing so from a methodologically agnostic anthropological standpoint. It focuses on three key elements of his argument: his construal of the problem of immanence, his account of secularisation and his treatment of science as an (inadequate) antidote to religion. The critique contains within it the ingredients for an alternative, anthropologically grounded approach to secularity, secularism and secularisation. In this spirit, it moves towards examining actually existing secularity as a syncretic phenomenon that is, in significant respects, definitive of modernity.
Evaluation of Serum NT‐pCNP as a Diagnostic and Prognostic Biomarker for Sepsis in Dogs
Authors: DeClue A.E. , Osterbur K. , Bigio A. , Sharp C.R.
Published: April 2011

Background: There is a need for diagnostic biomarkers that can rapidly differentiate dogs with sepsis from dogs with noninfectious forms of systemic inflammatory response syndrome (NSIRS).

Objectives: To compare serum NT‐pCNP concentrations among dogs with various forms of sepsis, NSIRS, and healthy controls and to evaluate the use of serum NT‐pCNP for the diagnosis of various forms of sepsis in dogs.

Animals: One hundred and twelve dogs including 63 critically ill dogs (sepsis n = 29; NSIRS n = 34) and 49 healthy control dogs.

Methods: Prospective clinical investigation. Serum samples were collected for NT‐pCNP measurement from dogs with sepsis or NSIRS within 24 hours of intensive care unit admission or at the time of presentation for healthy dogs. Dogs with sepsis were subclassified based on the anatomic region of infection. Serum NT‐pCNP concentrations were compared among sepsis, NSIRS and healthy groups as well as among sepsis subgroups. The area under the curve (AUC), sensitivity, and specificity for identifying dogs with sepsis were determined.

Results: Using a cut‐off value of 10.1 pmol/L, AUC, sensitivity, and specificity of NT‐pCNP for differentiating dogs with sepsis from dogs with NSIRS or healthy control dogs were 0.71 (95% CI, 0.58–0.85), 65.5% (45.7–82.1%), and 89.2% (80.4–94.9%), respectively. Serum NT‐pCNP had poor sensitivity for peritoneal sources of sepsis; AUC [0.92 (0.81–1.0)], sensitivity [94% (71–100%)], and specificity [89% (80–95%)] improved when these dogs were excluded. Serum NT‐pCNP concentration was not associated with survival in the sepsis group.

Conclusions and Clinical Importance: Serum NT‐pCNP is a promising diagnostic biomarker for sepsis but is a poor indicator of septic peritonitis.
Effects of Intravenously Administered Esomeprazole Sodium on Gastric Juice pH in Adult Female Horses
Authors: Videla R. , Sommardahl C.S. , Elliott S.B. , Vasili A. , Andrews F.M.
Published: April 2011

Background:Gastric ulcers are common in horses and treatment of horses that cannot be administered oral medication can be problematic.

Objectives:To evaluate the efficacy of esomeprazole sodium administered intravenously on gastric juice pH and gastric ulcer scores in horses.

Animals:Twelve adult female Quarter Horses.

Methods:Esomeprazole sodium (0.5 mg/kg IV) was administered once daily to 8 horses (treatment group) and saline (5 mL IV) was administered to 4 horses (control group) for 13 consecutive days. Gastroscopy was performed and gastric juice pH and gastric ulcer score were recorded before and 1 hour after the administration of esomeprazole sodium or saline on days 1 and 5, then on day 14, 23 hours after the 13th daily dose of esomeprazole sodium or saline.

Results:When compared with values before treatment, gastric juice pH was higher in esomeprazole sodium‐treated horses after treatment (4.25 ± 2.39 versus 6.43 ± 1.18;P= .002). Also, gastric juice pH was higher (P= .001) in esomeprazole sodium‐treated horses compared with saline‐treated control horses on day 5 and on day 14 values. Gastric ulcers were seen in 5/12 (43%) horses in the study.

Conclusions and Clinical Importance:Esomeprazole sodium shows promise for treatment of gastric ulcers in horses with signs of dysphagia, gastric reflux, or other conditions that restrict oral intake of the current Federal Drug Administration‐approved omeprazole paste.
Some Advancements to Visualizing Constrained Functions and Inequalities of Two Variables 1
Authors: Simionescu P. A.
Published: April 2011

Based on the problem of visualizing the potential energy of a two-degree-of-freedom spring-mass system restrained by an elastic string, several advancements to visualizing functions with constraints and inequalities of two variables are introduced. These innovations include logarithmically spacing level curves (either mapped on the surface or projected on the bottom plane) and the possibility of truncating the portions of the function surface that exceed above and below the bounding box—both allowing better detailing of certain regions of the function surface, in particular the minimum and maximum areas. By selectively displaying the surface patches that either intersect or not the top and/or bottom planes of the bounding box in a truncated representation, sets of inequalities of two variables can be represented graphically in a suggestive manner. Also proposed are a new approach to producing the gradient of the function as an arrow field mapped on the bottom of the plot box that uses a finite-difference scheme applied to the 2D image-space nodes of the function surface rather than the original 3D data, and a new way of displaying the color scale in 3D surface plots.
Dynamics of Axially Accelerating Beams With an Intermediate Support
Authors: Bağdatli S. M. , Özkaya E. , Öz H. R.
Published: April 2011

The transverse vibrations of an axially accelerating Euler–Bernoulli beam resting on simple supports are investigated. The supports are at the ends, and there is a support in between. The axial velocity is a sinusoidal function of time varying about a constant mean speed. Since the supports are immovable, the beam neutral axis is stretched during the motion, and hence, nonlinear terms are introduced to the equations of motion. Approximate analytical solutions are obtained using the method of multiple scales. Natural frequencies are obtained for different locations of the support other than end supports. The effect of nonlinear terms on natural frequency is calculated for different parameters. Principal parametric resonance occurs when the velocity fluctuation frequency is equal to approximately twice of natural frequency. By performing stability analysis of solutions, approximate stable and unstable regions were identified. Effects of axial velocity and location of intermediate support on the stability regions have been investigated.
Approximation of Transient 1D Conduction in a Finite Domain Using Parametric Fractional Derivatives
Authors: Pineda Sergio M. , Diaz Gerardo , Coimbra Carlos F. M.
Published: April 2011

A solution to the problem of transient one-dimensional heat conduction in a finite domain is developed through the use of parametric fractional derivatives. The heat diffusion equation is rewritten as anomalous diffusion, and both analytical and numerical solutions for the evolution of the dimensionless temperature profile are obtained. For large slab thicknesses, the results using fractional order derivatives match the semi-infinite domain solution for Fourier numbers, Fo∊[0,1/16]. For thinner slabs, the fractional order solution matches the results obtained using the integral transform method and Green’s function solution for finite domains. A correlation is obtained to display the variation of the fractional order p as a function of dimensionless time (Fo) and slab thickness (ζ) at the boundary ζ=0.
An alternating focused ultrasound system for thermal therapy studies in small animals
Authors: Chen Xin , Novák Petr , Benson Donald G. , Webber Jessica S. , Hennings Leah , Shafirstein Gal , Corry Peter M. , Griffin Robert J. , Moros Eduardo G.
Published: April 2011

Purpose:

To develop an alternating focused ultrasound system (AFUS) for preclinical studies of thermal and acoustic responses of tumors in small animal models. This work was motivated by the need of noninvasively creating relatively small spheroidal thermal lesions in small targets (e.g., a murine tumor) without damaging the surrounding tissues.

Methods:

The AFUS consists of two lead zirconate titanate (PZT‐4) spherically curved ultrasound transducers with focal zones crossing each other at a 90° angle. The transducers were independently powered following a programed alternating firing scheme. Before the device design and construction, an acoustic and biothermal model was developed to simulate the ultrasound pressure field and the resulting temperature and thermal dose distributions. A shape factor, sphericity, to quantify the roundness of the lesions was calculated based on the 240 equivalent minutes at thermal dose contours. A prototype of the AFUS was constructed with two identical transducers of an operating frequency of 2.25 MHz, 38 mm in diameter, and ‐number equal to 1.33. To evaluate the performance of the AFUS experimentally, a series of heating in polyacrylamide phantoms, ex vivo porcine liver tissues, and in implanted mouse tumors fibrosarcoma (FSaII) in vivo was conducted. In these experimental cases, the sphericity was calculated and compared based on the visible lesion (a marked change in coloration).

Results:

As shown in the simulations, the lesions induced in polyacrylamide phantoms,ex vivo porcine liver tissues, and in vivo mouse tumors, the sphericities of the lesions yielded by AFUS heating were approximately 50% higher than those of single focused ultrasound heating as long as moderate intensities were used and the duty cycle pulses were distributed equally among the transducers.

Conclusions:

The AFUS is a device capable of noninvasively creating spheroidal thermal lesions in small targets such as murine tumors.
Comparison of 250 MHz electron spin echo and continuous wave oxygen EPR imaging methods for in vivo applications
Authors: Epel Boris , Sundramoorthy Subramanian V. , Barth Eugene D. , Mailer Colin , Halpern Howard J.
Published: April 2011

Purpose:

The authors compare two electron paramagnetic resonance imaging modalities at 250 MHz to determine advantages and disadvantages of those modalities forin vivo oxygen imaging.

Methods:

Electron spin echo (ESE) and continuous wave (CW) methodologies were used to obtain three‐dimensional images of a narrow linewidth, water soluble, nontoxic oxygen‐sensitive trityl molecule OX063in vitro and in vivo. The authors also examined sequential images obtained from the same animal injected intravenously with trityl spin probe to determine temporal stability of methodologies.

Results:

A study of phantoms with different oxygen concentrations revealed a threefold advantage of the ESE methodology in terms of reduced imaging time and more precise oxygen resolution for samples with less than 70 torr oxygen partial pressure. Above , CW performed better. The images produced by both methodologies showed distributions with similar mean values. However, ESE images demonstrated superior performance in low regions while missing voxels in high regions.

Conclusions:

ESE and CW have different areas of applicability. ESE is superior for hypoxia studies in tumors.
Subzone based magnetic resonance elastography using a Rayleigh damped material model
Authors: Van Houten Elijah E.W. , Viviers D. vR. , McGarry M. D.J. , Perriñez P. R. , Perreard I. I. , Weaver J. B. , Paulsen K. D.
Published: April 2011

Purpose:

Recently, the attenuating behavior of soft tissue has been addressed in magnetic resonance elastography by the inclusion of a damping mechanism in the methods used to reconstruct the resulting mechanical property image. To date, this mechanism has been based on a viscoelastic model for material behavior. Rayleigh, orproportional, damping provides a more generalized model for elastic energy attenuation that uses two parameters to characterize contributions proportional to elastic and inertial forces. In the case of time‐harmonic vibration, these two parameters lead to both the elastic modulus and the density being complex valued (as opposed to the case of pure viscoelasticity, where only the elastic modulus is complex valued).

Methods:

This article presents a description of Rayleigh damping in the time‐harmonic case, discussing the differences between this model and the viscoelastic damping models. In addition, the results from a subzone based Rayleigh damped elastography study of gelatin and tofu phantoms are discussed, along with preliminary results fromin vivo breast data.

Results:

Both the phantom and the tissue studies presented here indicate a change in the Rayleigh damping structure, described asRayleigh composition, between different material types, with tofu and healthy tissue showing lower Rayleigh composition values than gelatin or cancerous tissue.

Conclusions:

It is possible that Rayleigh damping elastography and the concomitant Rayleigh composition images provide a mechanism for differentiating tissue structure in addition to measuring elastic stiffness and attenuation. Such information could be valuable in the use of Rayleigh damped magnetic resonance elastography as a diagnostic imaging tool.
Normal tissue dose conformality measures to guide radiotherapy fractionation decisions
Authors: Myerson Robert J.
Published: April 2011

Purpose:

To determine conditions under which hypofractionation could be favorable for a normal tissue—even if tumor exceeds the normal tissue's .

Methods:

The hypofractionation sufficiency condition (HSC) for an organ is defined as a dose conformality constraint such that, if satisfied, a family of tumor control probability isoeffective fractionation schemes will showdecreasing normal tissue complication probability with decreasing number of fractions.

Results:

In the extended equivalent uniform dose (EUD) model [obtained by replacing dose with linear quadratic (LQ) 2 Gy equivalent dose], the HSC for a normal organ is proven to be satisfied if a suitably weighted average of the relative dose [hypofractionation sufficiency index (HSI)] is less than the ratio of normal tissue to tumor . The HSI is determined solely by dose distribution and the normal tissue volume factor, “.” If the HSC is satisfied for every normal tissue of concern, then there is a therapeutic gain with hypofractionation. The corresponding multifractionation sufficiency condition (therapeutic gain with increasing number of fractions) and multifractionation sufficiency index (MSI) are also derived. A sample clinical case is presented.

Conclusions:

Within the context of the LQ/EUD models, conformality measures (HSI and MSI) can be used to inform fractionation decisions.
Optimization of a parallel hole collimator/CdZnTe gamma‐camera architecture for scintimammography
Authors: Robert Charlotte , Montémont Guillaume , Rebuffel Véronique , Verger Loïck , Buvat Irène
Published: April 2011

Purpose:

Small field‐of‐view CdZnTe (CZT) gamma cameras are increasingly studied for breast lesion detection to complement mammography or ultrasonographic findings. However, in classical collimation configurations, they remain limited by the trade‐off between spatial resolution and sensitivity. The HiSens architecture was proposed to overcome these limitations. Using an accurate 3D localization of the interactions inside the detector, this architecture leads to a gain in sensitivity without loss in spatial resolution. In this article, the relevance of the HiSens architecture for planar scintimammography is studied.

Methods:

A detective quantum efficiency (DQE) computation method is developed and used to optimize the dimensioning of a parallel hole collimator dedicated to scintimammography. Based on the DQE curves, the impact of the collimator‐to‐detector distance is studied. Two algorithms are proposed to combine data acquired with different collimator‐to‐detector distances.

Results:

It is shown that CZT detector virtual pixelization increases system sensitivity by 3.3 while preserving a standard LEHR spatial resolution. The introduction of a gap between the CZT detector and the collimator is useful to modulate the DQE curve shape. The combination of data acquired using different gaps in the image formation process leads to enhanced restoration of the frequency content of the images, resulting in image contrast and spatial resolution improvements.

Conclusions:

Acquisition duration or injected activity could be markedly reduced if the HiSens architecture with an appropriate collimator‐detector gap were used.
An analysis of confidence limit calculations used in AAPM Task Group No. 119
Authors: Knill Cory , Snyder Michael
Published: April 2011

Purpose:

The report issued by AAPM Task Group No. 119 outlined a procedure for evaluating the effectiveness of IMRT commissioning. The procedure involves measuring gamma pass‐rate indices for IMRT plans of standard phantoms and determining if the results fall within a confidence limit set by assuming normally distributed data. As stated in the TG report, the assumption of normally distributed gamma pass rates is a convenient approximation for commissioning purposes, but may not accurately describe the data. Here the authors attempt to better describe gamma pass‐rate data by fitting it to different distributions. The authors then calculate updated confidence limits using those distributions and compare them to those derived using TG No. 119 method.

Methods:

Gamma pass‐rate data from 111 head and neck patients are fitted using the TG No. 119 normal distribution, a truncated normal distribution, and a Weibull distribution. Confidence limits to 95% are calculated for each and compared. A more general analysis of the expected differences between the TG No. 119 method of determining confidence limits and a more time‐consuming curve fitting method is performed.

Results:

The TG No. 119 standard normal distribution does not fit the measured data. However, due to the small range of measured data points, the inaccuracy of the fit has only a small effect on the final value of the confidence limits. The confidence limits for the 111 patient plans are within 0.1% of each other for all distributions. The maximum expected difference in confidence limits, calculated using TG No. 119's approximation and a truncated distribution, is 1.2%.

Conclusions:

A three‐parameter Weibull probability distribution more accurately fits the clinical gamma index pass‐rate data than the normal distribution adopted by TG No. 119. However, the sensitivity of the confidence limit on distribution fit is low outside of exceptional circumstances.
Similarity evaluation in a content‐based image retrieval (CBIR) CADx system for characterization of breast masses on ultrasound images
Authors: Cho Hyun‐chong , Hadjiiski Lubomir , Sahiner Berkman , Chan Heang‐Ping , Helvie Mark , Paramagul Chintana , Nees Alexis V.
Published: April 2011

Purpose:

The authors are developing a content‐based image retrieval (CBIR) CADx system to assist radiologists in characterization of breast masses on ultrasound images. In this study, the authors compared seven similarity measures to be considered for the CBIR system. The similarity between the query and the retrieved masses was evaluated based on radiologists' visual similarity assessments.

Methods:

The CADx system retrieves masses that are similar to a query mass from a reference library based on computer‐extracted features using a ‐nearest neighbor approach. Among seven similarity measures evaluated for the CBIR system, four similarity measures including linear discriminant analysis (LDA), Bayesian neural network (BNN), cosine similarity measure (Cos), and Euclidean distance (ED) similarity measure were compared by radiologists' visual assessment. For LDA and BNN, the features of a query mass were combined first into a malignancy score and then masses with similar scores were retrieved. For Cos and ED, similar masses were retrieved based on the normalized dot product and the Euclidean distance, respectively, between two feature vectors. For the observer study, three most similar masses were retrieved for a given query mass with each method. All query‐retrieved mass pairs were mixed and presented to the radiologists in random order. Three Mammography Quality Standards Act (MQSA) radiologists rated the similarity between each pair using a nine‐point similarity scale ( dissimilar, similar). The accuracy of the CBIR CADx system using the different similarity measures to characterize malignant and benign masses was evaluated by ROC analysis.

Results:

The BNN measure used with the classifier provided slightly higher performance for classification of malignant and benign masses ( values of 0.87) than those with the LDA, Cos, and ED measures ( of 0.86, 0.84, and 0.81, respectively). The average similarity ratings of all radiologists for LDA, BNN, Cos, and ED were 4.71, 4.95, 5.18, and 5.32, respectively. The with the ED measures retrieved masses of significantly higher similarity than LDA and BNN.

Conclusions:

Similarity measures using the resemblance of individual features in the multidimensional feature space can retrieve visually more similar masses than similarity measures using the resemblance of the classifier scores. A CBIR system that can most effectively retrieve similar masses to the query may not have the best .
Assessing software upgrades, plan properties and patient geometry using intensity modulated radiation therapy (IMRT) complexity metrics
Authors: McGarry Conor K. , Chinneck Candice D. , O'Toole Monica M. , O'Sullivan Joe M , Prise Kevin M. , Hounsell Alan R.
Published: April 2011

Purpose:

The aim of this study is to compare the sensitivity of different metrics to detect differences in complexity of intensity modulated radiation therapy (IMRT) plans following upgrades, changes to planning parameters, and patient geometry. Correlations between complexity metrics are also assessed.

Method:

A program was developed to calculate a series of metrics used to describe the complexity of IMRT fields using monitor units (MUs) and multileaf collimator files: Modulation index (MI), modulation complexity score (MCS), and plan intensity map variation (PIMV). Each metric, including the MUs, was used to assess changes in beam complexity for six prostate patients, following upgrades in the inverse planning optimization software designed to incorporate direct aperture optimization (DAO). All beams were delivered to a 2D ionization chamber array and compared to those calculated using gamma analysis. Each complexity metric was then calculated for all beams, on a different set of six prostate IMRT patients, to assess differences between plans calculated using different minimum field sizes and different maximum segment numbers. Different geometries, including CShape, prostate, and head and neck phantoms, were also assessed using the metrics. Correlations between complexity metrics were calculated for 20 prostate IMRT patients.

Results:

MU, MCS, MI, and PIMV could all detect reduced complexity following an upgrade to the optimization leaf sequencer, although only MI and MCS could detect a reduction in complexity when one‐step optimization (DAO) was employed rather than two‐step optimization. All metrics detected a reduction in complexity when the minimum field size was increased from 1 to 4 cm and all apart from PIMV detected reduced complexity when the number of segments was significantly reduced. All metrics apart from MI showed differences in complexity depending on the treatment site. Significant correlations exist between all metrics apart from MI and PIMV for prostate IMRT patients. Treatment deliverability appeared to be more correlated with MI and MCS than MU or PIMV.

Conclusions:

The application of complexity metrics in the IMRT treatment planning process has been demonstrated. Complexity of treatment plans can vary for different inverse planning software versions and can depend on planning parameters and the treatment site. MCS is most suitable for inclusion within the cost function to limit complexity in IMRT optimization due to its sensitivity to complexity changes and correlation to treatment deliverability.
Oblique incidence effects in direct x‐ray detectors: A first‐order approximation using a physics‐based analytical model
Authors: Badano Aldo , Freed Melanie , Fang Yuan
Published: April 2011

Purpose:

The authors describe the modifications to a previously developed analytical model of indirect CsI:Tl‐based detector response required for studying oblique x‐ray incidence effects in direct semiconductor‐based detectors. This first‐order approximation analysis allows the authors to describe the associated degradation in resolution in direct detectors and compare the predictions to the published data for indirect detectors.

Methods:

The proposed model is based on a physics‐based analytical description developed by Freed et al. [“A fast, angle‐dependent, analytical model of CsI detector response for optimization of 3D x‐ray breast imaging systems,” Med. Phys. 37(6), 2593–2605 (2010)] that describes detector response functions for indirect detectors and oblique incident x rays. The model, modified in this work to address direct detector response, describes the dependence of the response with x‐ray energy, thickness of the transducer layer, and the depth‐dependent blur and collection efficiency.

Results:

The authors report the detector response functions for indirect and direct detector models for typical thicknesses utilized in clinical systems for full‐field digital mammography ( for indirect CsI:Tl and for ‐Se direct detectors). The results suggest that the oblique incidence effect in a semiconductor detector differs from that in indirect detectors in two ways: The direct detector model produces a sharper overall PRF compared to the response corresponding to the indirect detector model for normal x‐ray incidence and a larger relative increase in blur along the x‐ray incidence direction compared to that found in indirect detectors with respect to the response at normal incidence angles.

Conclusions:

Compared to the effect seen in indirect detectors, the direct detector model exhibits a sharper response at normal x‐ray incidence and a larger relative increase in blur along the x‐ray incidence direction with respect to the blur in the orthogonal direction. The results suggest that the oblique incidence effect in direct detectors can be considered to be caused mostly by the geometry of the path where the x‐ray beam and its secondary particles deposit energy in the semiconductor layer.
Proteoglycan-Specific Molecular Switch for RPTPσ Clustering and Neuronal Extension
Authors: Coles Charlotte H. , Shen Yingjie , Tenney Alan P. , Siebold Christian , Sutton Geoffrey C. , Lu Weixian , Gallagher John T. , Jones E. Yvonne , Flanagan John G. , Aricescu A. Radu
Published: April 2011

One receptor binds two different types of proteoglycan at the same site but with divergent outcomes.
Approach to ocular examination in small animals
Authors: Mitchell Natasha
Published: April 2011

While a thorough ocular examination is clearly important in the diagnostic work‐up of dogs and cats presenting with eye conditions, an assessment of the eyes should also be included in every routine health check in small animal practice. Eye examinations require basic equipment, good clinical observation and lots of practice. It is also important for clinicians to be familiar with the normal anatomy of the eye, so that abnormalities can be recognised and the significance of the findings appreciated. This article describes a step‐by‐step approach to examination of the eye in dogs and cats, and highlights the key diagnostic tests that should be carried out as part of this procedure.
Orthopaedic examination of the dog
Authors: Arthurs Gareth
Published: April 2011

An orthopaedic examination should help to determine whether the cause of any lameness, weakness, lethargy, intolerance, ataxia or incoordination is due to an orthopaedic condition, to localise the orthopaedic condition, to formulate a plan of appropriate further diagnostic tests such as radiography, joint taps or computed tomography, and, subsequently, to plan treatment options. Part 1, published in the March issue of In Practice, discussed a systematic approach to the orthopaedic examination, from patient presentation to planning and procedure, and considered how this could be applied to the thoracic limb. This article describes how to perform an orthopaedic examination on the pelvic limb. An article published in the February issue of In Practice described the use of orthopaedic examination as part of an approach to hindlimb lameness.
Comments on the dilemma in the March issue: ‘Principled profit‐sharing?’
Authors: Mullan Siobhan
Published: April 2011

The dilemma in the March issue concerned a principal of a practice who was considering introducing a profit incentive scheme (In Practice, March 2011, volume 33, pages 142–143). There were preliminary discussions with employees, some of whom were unsure about how such a scheme would affect the way they performed their duties. Glen Cousquer commented that profit‐sharing, either explicitly or implicitly, provided vets with an incentive to work for financial gain. For some, this would be their main (or only) motivation, whereas for others it remained secondary to other values such as public service or an interest in animal welfare and veterinary medicine. A possible way forward would be to remember that vets had a duty to the greater good, society, the profession, the client and the patient, as well as their employer. As such, their remuneration should be fair but not tip the balance in favour of exploitation of vulnerable clients and insurance companies. Vets should feel comfortable explaining the reasons why they were recommending a particular course of action, especially where cheaper options were available.
Republished review: The world through a lens: the vision of Sir Harold Ridley
Authors: Moore D B , Harris A , Siesky B
Published: April 2011

Sir Harold Ridley is recognised today as the inventor of intraocular lens implantation, one the most successful and common procedures in all of surgery. His story, however, is not largely one of triumph and public accolade. This paper reviews Ridley's invention of the intraocular lens and highlights the struggles he faced after his discovery.
Republished paper: Meta-analysis of the effect of comprehensive smoke-free legislation on acute coronary events
Authors: Mackay D F , Irfan M O , Haw S , Pell J P
Published: April 2011

Objective

To assess the evidence for a reduced risk of acute coronary events following comprehensive smoke-free legislation.

Methods

Two independent systematic reviews were undertaken using PubMed, Embase and Science Direct with no date restrictions imposed. Meta-analysis was undertaken using a random effects model to obtain a pooled estimate of the relative risk. Linear regression was used to examine possible bias and meta-regression was used to investigate possible causes of heterogeneity.

Main outcome measure

Acute coronary events.

Results

The 17 eligible studies (10 from North America, 6 from Europe and 1 from Australasia) provided 35 estimates of effect size. Apart from five subgroup analyses, all of the published results suggested a reduction in the incidence of acute coronary events following the introduction of smoke-free legislation. Meta-analysis produced a pooled estimate of the relative risk of 0.90 (95% CI 0.86 to 0.94). There was significant heterogeneity (overall I2=95.1%, p<0.001) but there was no evidence of small study bias (p=0.714). On univariate random effects meta-regression analysis, studies with longer data collection following legislation produced greater estimates of risk reduction and remained significant after adjustment for other study characteristics (adjusted coefficient −0.005, 95% CI −0.007 to −0.002, multiplicity adjusted p=0.006).

Conclusions

There is now a large body of evidence supporting a reduction in acute coronary events following the implementation of comprehensive smoke-free legislation, with the effect increasing over time from implementation. Countries that have not yet adopted smoke-free legislation should be encouraged to do so.
MICROSTRUCTURE AND MAGNETORESISTANCE OFCaCuxMn3-xMn4O12
Authors: CAO H. , TAN W. S. , XU G. J. , WU H. P. , DENG K. M. , WU X. S.
Published: April 2011

In this article, the precursors of CaCuxMn3-xMn4O12(x = 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4) were synthesized using wet-chemistry technique, and then samples were sintered in pure oxygen flow at 850°C and ambient pressure with KCl 10 wt% addition. The Rietveld refinements of powder X-ray diffraction patterns showed that all the samples were single phase with cubic symmetry, the space group [Formula: see text]. The lattice parameters a decreased with increasing Cu doping level x. The transport properties were characterized with DC four-probe technique. The results indicated that the crystal structure of samples were deformed and then influenced the transport properties of these manganese oxides. The MR ratios at 85 K and in the magnetic field of 5 Tesla increased with increasing x and reached the maximum at x = 1.0, then decreased with further increasing x. These results originated maybe from the intergrain tunneling of spin-polarized carriers and double-exchange effect.
DIRECTOR FIELD OF DISCLINATION LINE IN UNIAXIAL NEMATIC LIQUID CRYSTAL IN THE PRESENCE OF MAGNETIC FIELD
Authors: KADIVAR ERFAN
Published: April 2011

Using the Oseen–Zöcher–Frank theory, in the steady state, I study the distortion energy of a disclination line in nematic liquid crystal in the presence of an external magnetic field. The director field around a disclination line is exactly calculated by minimizing the total free energy. The behavior of total free energy as a function of magnetic field for two kinds of nematic material (positive and negative magnetic anisotropy) are discussed. In the short distance limit, the total free energy per unit length is calculated. In this case, the magnetic dependence of total free energy is discussed.
NEW RANDOM ORDERED PHASE IN ISOTROPIC MODELS WITH MANY-BODY INTERACTIONS
Authors: HASHIZUME YOICHIRO , SUZUKI MASUO
Published: April 2011

In this study, we have found a new random ordered phase in isotropic models with many-body interactions. Spin correlations between neighboring planes are rigorously shown to form a long-range order, namely coplanar spin-pair order, using a unitary transformation, and the phase transition of this new order has been analyzed on the bases of the mean-field theory and correlation identities. In the systems with regular 4-body interactions, the transition temperature T c is obtained as T c = (z-2)J/k B , and the field conjugate to this new order parameter is found to be H2. In contrast, the corresponding physical quantities in the systems with random 4-body interactions are given by [Formula: see text] and H4, respectively. Scaling forms of order parameters for regular or random 4-body interactions are expressed by the same scaling functions in the systems with regular or random 2-body interactions, respectively. Furthermore, we have obtained the nonlinear susceptibilities in the regular and random systems, where the coefficient χnl of H3 in the magnetization shows positive divergence in the regular model, while the coefficient χ7 of H7 in the magnetization shows negative divergence in the random model.
FREQUENCY DEPENDENCE OF THE GRAIN-BOUNDARY CONDUCTIVITY IN (Y2O3, CaO)-STABILIZED ZrO2
Authors: LI TONGWEI , JU WEIWEI , ZHANG JINCANG
Published: April 2011

Five samples of mixed Y 2 O 3/ CaO doped ZrO 2 electrolytes, with the same nominal chemical composition of ( ZrO 2)0.90–( Y 2 O 3)0.04-( CaO )0.06, were sintered at 1600°C for 2, 4, 6, 8 and 10 h, respectively. The frequency dependence of the grain-boundary conductivity of each sample was measured using complex impedance method in the temperature range from 773 to 1073 K and experimental results were analyzed according to a power law, which was frequently referred to as the so-called universal dynamic response (UDR). Results indicated the apparent ac grain-boundary conductivity can be well-described by the power law and some useful information about the grain-boundary effect, such as the activation energy of the grain-boundary conduction and the dissociated energy of the charge carrier in the space charge layer, can be obtained by analyzing the temperature dependence of the power law parameters.
DYNAMICS OF A THREE-LEVEL ATOM INTERACTING WITH A BIMODAL FIELD IN A RESONANT CAVITY
Authors: GHOSH ARPITA
Published: April 2011

We have discussed the time evolution along with the nonclassicality phenomena of a system containing a vee-type three-level atom interacting with a bimodal electromagnetic field. A general expression for the atomic inversion is presented. It is found that the model undergoes Rabi oscillation. The total noise of the output state is measured.
PAINLEVÉ ANALYSIS, LAX PAIR AND BÄCKLUND TRANSFORMATION FOR THE GROSS–PITAEVSKII EQUATION IN THE BOSE–EINSTEIN CONDENSATES
Authors: QI FENG-HUA , TIAN BO , XU TAO , ZHANG HAI-QIANG , LI LI-LI , MENG XIANG-HUA , LÜ XING , LIU WEN-JUN
Published: April 2011

Due to their relevance to physics and technology, the Bose–Einstein condensates (BECs) are of current interest. Certain dynamics of the BECs, such as the cigar-shaped condensate confined in a cylindrically symmetric parabolic trap, can be described by the Gross–Pitaevskii (GP) equation with a time-dependent trap. In this paper, by virtue of the Painlevé analysis and symbolic computation, we derive the integrable condition for the GP equation with the time-dependent scattering length in the presence of a confining or expulsive time-dependent trap. Lax pair for this equation is directly obtained via the Ablowitz–Kaup–Newell–Segur scheme under the integrable condition. Bright one-soliton-like solution of the GP equation is presented via the Bäcklund transformation and some analytic solutions with variable amplitudes are obtained by the ansatz method. In addition, an infinite number of conservation laws are also derived. Those results could be of some value for the studies on the lower-dimensional condensates.
STRESS TESTING THE RESILIENCE OF FINANCIAL NETWORKS
Authors: AMINI HAMED , CONT RAMA , MINCA ANDREEA
Published: April 2011

We propose a simulation-free framework for stress testing the resilience of a financial network to external shocks affecting balance sheets. Whereas previous studies of contagion effects in financial networks have relied on large scale simulations, our approach uses a simple analytical criterion for resilience to contagion, based on an asymptotic analysis of default cascades in heterogeneous networks. In particular, our methodology does not require to observe the whole network but focuses on the characteristics of the network which contribute to its resilience. Applying this framework to a sample network, we observe that the size of the default cascade generated by a macroeconomic shock across balance sheets may exhibit a sharp transition when the magnitude of the shock reaches a certain threshold: Beyond this threshold, contagion spreads to a large fraction of the financial system. An upper bound is given for the threshold in terms of the characteristics of the network.
HEAT KERNEL INTEREST RATE MODELS WITH TIME-INHOMOGENEOUS MARKOV PROCESSES
Authors: AKAHORI JIRÔ , MACRINA ANDREA
Published: April 2011

We consider a heat kernel approach for the development of stochastic pricing kernels. The kernels are constructed by positive propagators, which are driven by time-inhomogeneous Markov processes. We multiply such a propagator with a positive, time-dependent and decreasing weight function, and integrate the product over time. The result is a so-called weighted heat kernel that by construction is a supermartingale with respect to the filtration generated by the time-inhomogeneous Markov processes. As an application, we show how this framework naturally fits the information-based asset pricing framework where time-inhomogeneous Markov processes are utilized to model partial information about random economic factors. We present examples of pricing kernel models which lead to analytical formulae for bond prices along with explicit expressions for the associated interest rate and market price of risk. Furthermore, we also address the pricing of fixed-income derivatives within this framework.
Man Up Your Leadership: The European management perspective
Authors: Ferretti Maxime
Published: April 2011

An essential competent of learning often ignored is leadership training. With support from the European Commission Education, Audiovisual and Culture Executive Agency, Learn to Lead (L2L) has been developed to exercise and improve personal leadership skills. But before the game could be launched, one issue needed to be resolved: How to distinguish between management and leadership? Maxime Ferretti attempts to end this debate once and for all.
Coordinating e-health systems with TuCSoN semantic tuple centres
Authors: Nardini Elena , Omicini Andrea , Viroli Mirko , Schumacher Michael I.
Published: April 2011

Open and distributed application scenarios like e-Health systems mandate for new coordination models and technologies. In particular, they require middleware providing coordination and security services modelled with abstractions promoting run-time observability and adaptation.

Along this line, in this paper we describe the architecture of the TuCSoN coordination infrastructure, and show its application to an e-Health application scenario.
Performance analysis of the OP2 framework on many-core architectures
Authors: Giles M. B. , Mudalige G. R. , Sharif Z. , Markall G. , Kelly P. H.J.
Published: April 2011

We present a performance analysis and benchmarking study of the OP2 "active" library, which provides an abstraction framework for the solution of parallel unstructured mesh applications. OP2 aims to decouple the scientific specification of the application from its parallel implementation, achieving code longevity and near-optimal performance through re-targeting the back-end to different hardware.

Runtime performance results are presented for a representative unstructured mesh application written using OP2 on a variety of many-core processor systems, including the traditional X86 architectures from Intel (Xeon based on the older Penryn and current Nehalem micro-architectures) and GPU offerings from NVIDIA (GTX260, Tesla C2050). Our analysis demonstrates the contrasting performance between the use of CPU (OpenMP) and GPU (CUDA) parallel implementations for the solution on an industrial sized unstructured mesh consisting of about 1.5 million edges.

Results show the significance of choosing the correct partition and thread-block configuration, the factors limiting the GPU performance and insights into optimizations for improved performance.
Memory Trace Compression and Replay for SPMD Systems using Extended PRSDs?
Authors: Budanur Sandeep , Mueller Frank , Gamblin Todd
Published: April 2011

Concurrency levels in large-scale supercomputers are rising exponentially, and shared-memory nodes with hundreds of cores and non-uniform memory access latencies are expected within the next decade. However, even current petascale systems with tens of cores per node suffer from memory bottlenecks. As core counts increase, memory issues become critical for the performance of large-scale supercomputers. Trace analysis tools are vital for diagnosing the root causes of memory problems. However, existing tools are expensive due to prohibitively large trace sizes, or they collect only statistical summaries that omit valuable information.

In this paper, we present ScalaMemTrace, a novel technique for collecting memory traces in a scalable manner. ScalaMemTrace builds on prior trace methods with aggressive compression techniques to allow lossless representation of memory traces for dense algebraic kernels, with nearconstant trace size irrespective of the problem size or the number of threads. We further introduce a replay mechanism for ScalaMemTrace traces, and discuss the results of our prototype implementation on the x86 64 architecture.
The structural simulation toolkit
Authors: Rodrigues A. F. , Hemmert K. S. , Barrett B. W. , Kersey C. , Oldfield R. , Weston M. , Risen R. , Cook J. , Rosenfeld P. , Cooper-Balis E. , Jacob B.
Published: April 2011

As supercomputers grow, understanding their behavior and performance has become increasingly challenging. New hurdles in scalability, programmability, power consumption, reliability, cost, and cooling are emerging, along with new technologies such as 3D integration, GP-GPUs, silicon-photonics, and other "game changers". Currently, they HPC community lacks a unified toolset to evaluate these technologies and design for these challenges.

To address this problem, a number of institutions have joined together to create the Structural Simulation Toolkit (SST), an open, modular, parallel, multi-criteria, multi-scale simulation framework. The SST includes a number of processor, memory, and network models. The SST has been used in a variety of network, memory, and application studies and aims to become the standard simulation framework for designing and procuring HPC systems.
Unexpected results in online controlled experiments
Authors: Kohavi Ron , Longbotham Roger
Published: April 2011

Controlled experiments, also called randomized experiments and A/B tests, have had a profound influence on multiple fields, including medicine, agriculture, manufacturing, and advertising. Offline controlled experiments have been well studied and documented since Sir Ronald A. Fisher led the development of statistical experimental design while working at the Rothamsted Agricultural Experimental Station in England in the 1920s. With the growth of the world-wide-web and web services, online controlled experiments are being used frequently, utilizing software capabilities like ramp-up (exposure control) and running experiments on large server farms with millions of users. We share several real examples of unexpected results and lessons learned.
Tenth international workshop on multimedia data mining
Authors: Petrushin Valery A. , Pan Jia-Yu (Tim) , Snoek Cees G.M.
Published: April 2011

In this report we provide a summary of the tenth Multimedia Data Mining Workshop that was held in conjunction with the 16th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining (KDD 2010), July 25-28 in Washington, DC.
MultiClust 2010
Authors: Fern Xiaoli Z. , Davidson Ian , Dy Jennifer G.
Published: April 2011

Traditional clustering focuses on finding a single best clustering solution from data. However, given a single data set, one could interpret it in different ways. This is particularly true with complex data that has become prevalent in the data mining community: text, video, images and biological data to name a few. It is thus of practical interest to find all possible alternative and interesting clustering solutions from data. Recently there has been increasing interest on developing algorithms to discover multiple clustering solutions from complex data. This report provides a description of the first international workshop on this emerging topic --- SIGKDD MultiClust10: Discovering, Summarizing and Using Multiple Clusterings, which was held in Washington DC, on July 25th 2010. The workshop program consists of three invited talks and presentations of four full research papers and three short papers.