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Inferior
Terms modified by Inferior Selected AbstractsElectrocardiogram-Based Algorithm to Predict the Left Ventricular Lead Position in Recipients of Cardiac Resynchronization SystemsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2009SYLVAIN PLOUX M.D. Introduction: Biventricular pacing is associated with various electrocardiographic patterns depending on the position of the left ventricular (LV) lead. We aimed to develop an electrocardiogram-based algorithm to predict the position of the LV lead. Methods: The algorithm was developed in 100 consecutive recipients of cardiac resynchronization therapy (CRT) systems. QRS axis, morphology, and polarity were analyzed with a view to define the specific electrocardiographic characteristics associated with the various LV lead positions. The algorithm was prospectively validated in 50 consecutive CRT device recipients. Results: The first analysis of the algorithm was the QRS morphology in V1. A positive R wave in V1 suggested LV lateral or posterior wall stimulation. A QS pattern was specific of anterior LV leads. In the presence of an R wave in V1, V6 was analyzed to distinguish between an inferior and anterior LV lead. Inferior leads were never associated with a positive V6. To differentiate between lateral and posterior positions, we analyzed the pattern in V2. Lateral leads were associated with an R morphology in V1 and a negative V2. Posterior leads were associated with an R morphology in V1 and V2. The algorithm allowed a reliable distinction between an inferior or anterior and a lateral or posterior lead position in 90% of patients. Inferior, anterior, lateral, and posterior positions were reliably distinguished in 80% of patients. Conclusion: This algorithm predicted the position of the LV lead with a high sensitivity and predictive value. [source] Retinal nerve fibre layer of perimetrically unaffected eyes of glaucoma patients: an optical coherence tomography studyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 2 2009Stefano Da Pozzo MD PhD Abstract Purpose:, The aim of this study is to evaluate whether optical coherence tomography (StratusOCT) may detect early changes in perimetrically unaffected (PU) fellow eyes of glaucomatous patients by assessing retinal nerve fibre layer (RNFL) thickness parameters. Methods:, Thirty-seven glaucomatous patients with unilateral field loss and 34 age-matched controls were recruited. In glaucoma patients, PU and perimetrically affected fellow eyes were analysed separately. For each group, mean values (±SD) of RNFL thickness parameters were calculated and comparisons between fellow eyes of glaucoma patients and between healthy and PU eyes of glaucoma patients conducted with paired t -test and Mann,Whitney U -test, respectively. Proportion of clock-hour sectors flagged with probability <5% or <1% was collected and differences between healthy and PU eyes were evaluated on Fisher exact test. Results:, Global (Average Thickness) and sectoral parameters (Inferior and Nasal Average), Maximum thickness,minimum thickness (Max-min), as well as 2-o'clock (nasal side) and 6-o'clock sectors resulted significantly thinner in PU eyes than in control group. Proportion of eyes with clock-hour position flagged with probability <5% or <1% was not significantly different between healthy and PU eyes. Conclusion:, Despite a standard automated perimetry within normal limits, the StratusOCT detected both localized and diffuse RNFL thinning in PU eyes of glaucoma patients. These eyes should be considered at risk of developing functional damage over time and consequently require thorough monitoring for detecting any sign of progression. [source] GPU-based interactive visualization framework for ultrasound datasetsCOMPUTER ANIMATION AND VIRTUAL WORLDS (PREV: JNL OF VISUALISATION & COMPUTER ANIMATION), Issue 1 2009Sukhyun Lim Abstract Ultrasound imaging is widely used in medical areas. By transmitting ultrasound signals into the human body, their echoed signals can be rendered to represent the shape of internal organs. Although its image quality is inferior to that of CT or MR, ultrasound is widely used for its speed and reasonable cost. Volume rendering techniques provide methods for rendering the 3D volume dataset intuitively. We present a visualization framework for ultrasound datasets that uses programmable graphics hardware. For this, we convert ultrasound coordinates into Cartesian form. In ultrasound datasets, however, since physical storage and representation space is different, we apply different sampling intervals adaptively for each ray. In addition, we exploit multiple filtered datasets in order to reduce noise. By our method, we can determine the adequate filter size without considering the filter size. As a result, our approach enables interactive volume rendering for ultrasound datasets, using a consumer-level PC. Copyright © 2009 John Wiley & Sons, Ltd. [source] Organizing for Continuous Innovation: On the Sustainability of Ambidextrous OrganizationsCREATIVITY AND INNOVATION MANAGEMENT, Issue 3 2005Bart Van Looy Organizing for innovation does not present itself as a straightforward exercise. The complexities entailed when implementing an innovation strategy can be related directly to the multitude of objectives it comprises. Recently, several scholars have advanced the notions of semi- or quasi-structures and ambidextrous organizations to handle these multiple requirements. These organizational forms imply the simultaneous presence of different activities, exhibiting differences in technology and market maturation. As a consequence, financial returns will reflect this diversified resource allocation pattern. Moreover, as higher levels of complexity are being introduced; ambidextrous organizations will encounter additional, organizational, costs. Compared to organizations that focus on the most profitable part of the portfolio, ambidextrous organizations , ceteris paribus , tend to be inferior in terms of financial returns. Within this contribution we explore under which conditions ambidextrous organizations can outperform focused firms; considered a prerequisite for their sustainability. In order to do so, we develop an analytical framework depicting the differential value dynamics, focused and ambidextrous firms can enact. Our findings reveal the relevancy of adopting extended time frames as well as introducing interface management practices aimed at cross-fertilization. Finally, the synergetic potential of (underlying) technologies comes to the forefront as necessary in order for ambidextrous organizations to become sustainable. [source] Growth, etching morphology and spectra of LiAlO2 crystalCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2008Taohua Huang Abstract ,-LiAlO2 single crystal was successfully grown by Czochralski method. The crystal quality was characterized by X-ray rocking curve and chemical etching. The effects of air-annealing and vapor transport equilibration (VTE) on the crystal quality, etch pits and absorption spectra of LiAlO2 were also investigated in detail. The results show that the as-grown crystal has very high quality with the full width at half maximum (FWHM) of 17.7-22.6 arcsec. Dislocation density in the middle part of the crystal is as low as about 3.0×103 cm,2. The VTE-treated slice has larger FWHM value, etch pits density and absorption coefficient as compared with those of untreated and air-annealed slices, which indicates that the crystal quality became inferior after VTE treatment. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] P-26 CONVENTIONAL V THIN LAYER TECHNIQUES: A COMPARATIVE STUDY OF BRONCHIAL SPECIMENS USING CONVENTIONAL AND TWO LBC METHODS, THINPREP AND SUREPATHCYTOPATHOLOGY, Issue 2006J. L. Conachan The current, conventional method used is quick, easy and reasonably cheap but the nature of bronchial specimens themselves creates the need for a better preparation technique. Bronchial specimens often present with many obscuring features, such as blood and mucus, which can affect definitive diagnosis. In the study, the bronchial specimens underwent routine conventional preparation and that remaining was used to prepare an LBC slide. Both LBC methods were separately evaluated alongside the conventional method where, of the 44 specimens used, half were prepared using the conventional and ThinPrep and half with the conventional and SurePath. Evaluation forms were completed by pathologists who assessed all preparations. The results showed both LBC methods produced superior preparations that were better fixed, more cellular and had improved nuclear detail. They also removed a high percentage of background debris, were more diagnostically accurate and reduced the inadequate rate by a third. The conventional slides prepared from the same specimen as the SurePath had a lower average than those prepared with the ThinPrep. This indicated that the specimens used to evaluate the SurePath method were in fact inferior to those used for ThinPrep, with the SurePath slides showing only a slight improvement in overall quality. Despite LBC preparations reducing pathologist screening and reporting time, both methods are more labour intensive and less cost effective. The majority of laboratories are not in the financial situation to trial new methods that require extra training and more staff hours, and as such this study has highlighted an important question ,Do the benefits of better quality preparation and diagnostic accuracy offset an increase in time and cost'. [source] Variable-Pulse Nd:YAG Laser in the Treatment of Facial TelangiectasiasDERMATOLOGIC SURGERY, Issue 1 2006AVERY A. BEVIN MD BACKGROUND Variable-pulse 1,064 nm wavelength lasers have been used with good effectiveness on leg telangiectasias and reticular veins and have shown promising results on facial telangiectasias as well. OBJECTIVE To investigate the effectiveness of a variable-pulse neodymium:yttrium-aluminum-garnet (Nd:YAG) laser using a small spot size in the treatment of facial telangi-ectasias. METHODS Eight male patients (mean age 75 years) underwent a single treatment session using a variable-pulse 1.5 mm spot size Nd:YAG laser with epidermal cooling. Telangiectasia diameters were 0.3 to 2.0 mm. Test sites were performed using three pulse widths (3, 20, and 60 ms), with fluences varying depending on vessel size and response. Full treatments were per-formed using test parameters giving the best response. Thirteen weeks later, the patients returned for final evaluation and satisfaction rating. RESULTS Fluences ranged from 226 to 425 J/cm2, with smaller vessels requiring larger energies. Pulse duration was equally divided between the 20 and 60 ms settings. The shortest pulse width (3 ms) was inferior in all patients. Longer pulse durations achieved superior vessel elimination with minimal immediate purpura and no postinammatory hyperpigmentation. The average mean vessel clearance was 26 to 50% in half of the patients and 51 to 75% in the other half as evaluated by three unbiased dermatologists with extensive laser experience. CONCLUSION A small,spot size Nd:YAG laser using a pulse width of 20 ms or higher appears to be effective in clearing a significant percentage of facial telangectasias with a single pass. The side effects were minimal. [source] A Method of Augmenting the Cheek Area Through SMAS, subSMAS, and Subcutaneous Tissue Recruitment During Facelift SurgeryDERMATOLOGIC SURGERY, Issue 3 2003Dominic A. Brandy MD BACKGROUND As the human face ages, there is a depletion of fat that occurs in the submalar region. Various techniques such as fat transfers, fillers, alloplastic implants, and composite rhytidectomies have been used to augment this area in the past. OBJECTIVE To describe a technique that augments the submalar areas during facelift surgery without the use of fat transfer, fillers, alloplastic implants, or a risky composite technique. METHOD An oval is scribed over the depressed submalar areas preoperatively. During facelift surgery, a fusiform area is scribed over the SMAS. This fusiform is scribed so that the medial end is directed at the center of the submalar depression, and the lateral end is toward the posterior earlobe. A defect is created within the lateral aspect of the fusiform, but not the medial portion. The fusiform is subsequently closed with a 2-0 Ethibond suture using three horizontal mattress sutures and two interrupted sutures. Upon closure of this defect, SMAS, subSMAS, and subcutaneous tissue overlying the SMAS are recruited into the submalar defect by the simple phenomenon of dog-ear formation. Additionally, there is a component of frank elevation of the tissues inferior to the medial aspect of the fusiform and submalar space. RESULTS The aforementioned technique has been performed on 123 patients over 7 years and has resulted in consistently good improvement in the submalar space. The procedure is not difficult to learn, and good results can be achieved with initial cases. The learning curve was not found to be steep, with good results being achieved quickly. CONCLUSION Depression of the submalar space plays a significant role in creating an aged face. In the past, various fillers and/or alloplastic implants have been used to augment this region. A low-risk method is described that mobilizes SMAS, subSMAS, and subcutaneous tissues into the submalar space through the phenomenon of dog-ear formation after fusiform closure. [source] Atlas of the developing inner ear in zebrafishDEVELOPMENTAL DYNAMICS, Issue 4 2002Michele Miller Bever Abstract This report provides a description of the normal developing inner ear of the zebrafish, Danio rerio, with special focus on the pars inferior. Zebrafish specimens, ranging in age from 3 to 30 days postfertilization (dpf), were processed for standard histologic sections or with a paint-fill method to show three-dimensional morphogenesis of the membranous labyrinth. Adult zebrafish (age 2 years) were also processed for inner ear paint-fills. Although development of the semicircular canals occurs rapidly (by 3 dpf), the pars inferior develops more gradually during days 5,20 postfertilization. A rudimentary endolymphatic duct emerges by 8 dpf. Differentiated hair cells of the lagenar macula are evident by 15 dpf, in a chamber located lateral and posterior to the saccule. By 20 dpf, the saccule itself is separated from the utricle, but remains connected by means of the utriculosaccular foramen. The maculae neglectae, each with differentiated hair cells, lie on the floor of the utricle near this foramen. A medial connection between the sacculi of right and left ears, the transverse canal, is also complete by 20 dpf. A ridge of mesenchyme, previously undescribed, bisects the saccule in zebrafish fry at 20,30 dpf. The images in the paint-fill atlas should provide a baseline for future studies of mutant zebrafish ears. © 2002 Wiley-Liss, Inc. [source] Premixed insulin treatment for type 2 diabetes: analogue or human?DIABETES OBESITY & METABOLISM, Issue 5 2007Alan J. Garber The progressive nature of type 2 diabetes makes insulin initiation a necessary therapeutic step for many patients. Premixed insulin formulations containing both basal and prandial insulin (so called biphasic insulin) are often prescribed because they are superior to long- or intermediate-acting insulin in obtaining good metabolic control. In addition, they are considered as an attractive alternative to classical basal-bolus therapy as fewer daily injections are required. Premixed insulin formulations include conventional (e.g. biphasic human insulin 70/30, or 30/70 in European countries, BHI 30) and newer premixed human analogues (e.g. biphasic insulin aspart 70/30, or 30/70 in Europe, BIAsp 30; insulin lispro mix 75/25,Mix 75/25, or Mix 25/75 in Europe). Like conventional premixed human insulin, premixed insulin analogues contain a fixed proportion of soluble, rapid-acting insulin analogue, with protaminated analogue comprising the remainder. Unlike conventional premixes, analogue premixes have more physiological pharmacokinetic and therapeutically more desirable pharmacodynamic profiles than premixed human insulin. Consequently, postprandial glycaemic control is better with premixed insulin analogues than with premixed human insulin. In nontreat-to-target registration trials, the lowering of haemoglobin A1c with premixed insulin analogues was not inferior to that seen with premixed human insulin. Minor hypoglycaemia was similar for premixed analogue and premixed human insulins, while major hypoglycaemia appears to be rare with either formulation. The occurrence of adverse events, other than hypoglycaemia, was also similar between various premix insulins. The premixed insulin analogues, BIAsp 30 and Mix 75/25, like the fast-acting analogues from which they are derived, also allow flexible injection timing, relative to meal timing, thus improving adherence, compliance and quality of life compared with premixed human insulin. Overall, the evidence suggests that premixed insulin analogues are cost effective and have useful advantages over premixed human insulin for the treatment of type 2 diabetes. [source] Nuclear morphometry and texture analysis of B-cell non-Hodgkin lymphoma: Utility in subclassification on cytosmearsDIAGNOSTIC CYTOPATHOLOGY, Issue 2 2010Shilpa Gupta M.D. Abstract Non-Hodgkin lymphoma (NHL) is a heterogeneous group of lymphoid neoplasms and accurate subclassification is an essential prerequisite for proper management of patients. This study was aimed at evaluating the utility of nuclear morphometry and textural features on cytology smears to classify the cases of NHL on aspiration cytology. Fine needle aspiration smears of 50 cases of B-cell NHL were included. Various morphometric and texture parameters were obtained by manually tracing the nuclei on digitized images in each case and discriminant analysis performed using various features taken individually as well as all together. The percentage of cells correctly classified to a particular NHL subtype using the discriminant functions so obtained was noted. Our results show that discriminant analysis done on size parameters could correctly classify a greater number of cells than on shape parameters (36.4% vs. 21.2%, respectively). Texture parameters based on single pixel values (first order texture) were inferior (42.8%) to those based on pair of pixels (58.7%) in subtyping of cells. Discriminant analysis based on color parameters was more effective (61.9%) as compared to rest of the morphometric and textural parameters. Using all the morphometric and textural parameters together, 83.3% of cells could be correctly classified to a particular NHL subtype. The present study, perhaps the first study of detailed morphometric analysis on cytosmears, shows that satisfactory classification of NHL on aspiration cytology is possible using nuclear morphometry and textural parameters considered together. These results are promising for further studies on this subject and development of automated cytodiagnosis. Diagn. Cytopathol. 2010. © 2009 Wiley-Liss, Inc. [source] PRELIMINARY EXPERIENCE OF A PROTOTYPE FORWARD-VIEWING CURVED LINEAR ARRAY ECHOENDOSCOPE IN A TRAINING PHANTOM MODELDIGESTIVE ENDOSCOPY, Issue 2010Hiroshi Imaizumi Oblique-viewing curved linear array (OV-CLA) echoendoscopes have been widely used to perform endoscopic ultrasonography-guided fine needle aspiration and interventional endoscopic ultrasonography. Recently a prototype forward-viewing curved liner array (FV-CLA) echoendoscope was developed. In the present trial, 11 endoscopists participated in a hands-on trial and a questionnaire survey to evaluate the operation performance and visualization performance of a prototype FV-CLA scope in a phantom model designed for training of endoscopic ultrasonography. The results of our trial suggested that the FV-CLA scope is slightly inferior or equivalent to the conventional OV-CLA scope in operation performance, and that the FV-CLA scope is equivalent to the OV-CLA scope with regard to the visualization performance in a phantom model. [source] A Nomogram for Measurement of Mitral Valve Area by Proximal Isovelocity Surface Area MethodECHOCARDIOGRAPHY, Issue 8 2007Mehmet Uzun M.D. Introduction: Although its accuracy has been documented in many studies, the proximal isovelocity surface area (PISA) method is not used widely for mitral valve area (MVA) measurement. In this study, we prepared a new nomogram and tested its use in MVA assessment. Material and Methods: The study included 23 patients (age: 27 ± 5 years) with mitral stenosis, of whom 7 were in atrial fibrillation. The MVA was measured by four methods: planimetry (PL) (reference method), pressure-half time (PHT), conventional PISA (CP), and nomogram (Nomo) methods. The nomogram included two unknowns: (1) r; the radius of the first PISA section; (2) a; the length of the border opposite to the PISA angle in the triangle with both adjacent borders of 1 cm. The nomogram was also tested for its popularity potential by eight echocardiographers, none of whom were included in the author list. Results: Mean MVAPL was 1.85 ± 0.53 cm2 (range: 0.72,2.99), mean MVAPHT was 1.72 ± 0.56 cm2 (range: 0.91,3.30), mean MVACP was 1.69 ± 0.45 cm2 (range: 0.97,2.54), and MVANomo was 1.70 ± 0.44 cm2 (0.96,2.49). The nomogram correlated with planimetry (r = 0.87; P < 0.001), pressure half-time (r = 0.71; P < 0.001) and conventional PISA (r = 0.99; P = 0.000) methods. The nomogram method also correlated with planimetry in patients with atrial fibrillation (r = 0.81; P = 0.026). The echocardiographers found that the nomogram is superior to the planimetry and conventional PISA methods but inferior to the pressure half-time method in terms of simplicity. Conclusion: The new nomogram is potentially helpful in measurement of MVA. It may be used as an additional method in assessing severity of mitral stenosis. [source] The significance of overlapping plant range to a putative adaptive trade-off in the black bean aphid Aphis fabae ScopECOLOGICAL ENTOMOLOGY, Issue 4 2004C. R. Tosh Abstract., 1. This study continues to explore the analysis of a putative adaptive trade-off in the utilisation of host plants Vicia faba and Tropaeolum majus by the aphid, Aphis fabae. These plants are utilised exclusively by the subspecies Aphis fabae fabae and A. f. mordwilkoi respectively, and this plant-use system has been studied previously as a potential source of disruptive selection. 2. Here the potential of these two host plants to generate disruptive selection is considered given common utilisation of the abundant host plant, Rumex obtusifolius, by both subspecies. 3. The life history of subspecific clones is quantified in the laboratory on V. faba, T. majus, and R. obtusifolius at various temperatures and used to parameterise a temperature-driven simulation model of aphid population development. 4. Accuracy of the model is tested using a field experiment, and fitness of clones on specific and common host is simulated using temperature data from a number of English sites. 5. The model gives a close quantitative fit to field data and makes the following predictions: performance of A. f. fabae is higher on the specific host than the common host under all tested thermal regimes; and performance of A. f. mordwilkoi is superior on the specific host in warm years but inferior in cold years. 6. Given the great abundance of R. obtusifolius relative to T. majus, the model predicts that the plant utilisation system has little potential to consistently promote hybrid dysfunction. This adds further weight to the assertion that the plant utilisation system studied can offer little insight into the evolutionary processes involved in subspecific differentiation and probably contains a host plant/host plants acquired after the evolution of reproductive barriers. [source] Anticipating Regret: Why Fewer Options May Be BetterECONOMETRICA, Issue 2 2008Todd Sarver We study preferences over menus which can be represented as if the agent selects an alternative from a menu and experiences regret if her choice is ex post inferior. Since regret arises from comparisons between the alternative selected and the other available alternatives, our axioms reflect the agent's desire to limit her options. We prove that our representation is essentially unique. We also introduce two measures of comparative regret attitudes and relate them to our representation. Finally, we explore the formal connection between the present work and the literature on temptation. [source] FREE TRADE AREAS AND RULES OF ORIGIN: ECONOMICS AND POLITICSECONOMICS & POLITICS, Issue 2 2007RUPA DUTTAGUPTA Incorporating an intermediate input into a simple small-union general-equilibrium model, this paper first develops the welfare economics of preferential trading under the rules of origin (ROO) and then demonstrates that ROOs can improve the political viability of Free Trade Agreements (FTAs). Two interesting outcomes are derived. First, a welfare-reducing FTA that was rejected in the absence of ROOs can become feasible in the presence of these rules. Second, a welfare- improving FTA that was rejected in the absence of ROOs can be endorsed in their presence, but upon endorsement it can become welfare inferior relative to the status quo. [source] Voxel-based T2 Relaxation Rate Measurements in Temporal Lobe Epilepsy (TLE) with and without Mesial Temporal SclerosisEPILEPSIA, Issue 2 2007Susanne G. Mueller Summary:,Introduction: Quantitative measurements of T2 relaxation in the hippocampus for focus lateralization in mesial temporal lobe epilepsy (mTLE) are well established. Less is known to what degree such relaxation abnormalities also affect regions beyond the ipsilateral hippocampus. Therefore, the aim of this study was to characterize extent and distribution pattern of extrahippocampal relaxation abnormalities in TLE with (TLE-MTS) and without MRI evidence of mesial-temporal sclerosis (TLE-no). Methods: Double spin echo images (TE1/2: 20/80 ms) acquired in 24 TLE-MTS and 18 TLE-no were used to calculate relaxation rate maps. These maps were analyzed by SPM2 and by selecting regions of interest (ROI) in the hippocampus and several extrahippocampal brain regions. Results: In TLE-MTS, the results of the SPM and ROI analysis were in good agreement and showed the most severe relaxation rate decreases in the ipsilateral hippocampus but also in other ipsilateral temporal regions, orbitofrontal, and parietal regions and to a lesser degree in contralateral frontal regions. The relaxation rate decreases in TLE-no were confined to small regions in the ipsilateral anterior inferior and medial temporal lobe in the SPM analysis while ROI analysis showed additional regions in the ipsilateral hippocampus, amygdala, and anterior cingulate. Conclusion: TLE-MTS showed extensive, widespread but predominantly ipsilateral temporal and also extratemporal T2 relaxation rate decreases. In contrast, the findings of the SPM and ROI analyses in TLE-no suggested that if relaxation rate decreases are present, they are less uniform and generally milder than in TLE-MTS. This further supports the hypothesis that TLE-no is a distinct clinicopathological entity from TLE-MTS and probably heterogeneous in itself. [source] fMRI Lateralization of Expressive Language in Children with Cerebral LesionsEPILEPSIA, Issue 6 2006Dianne P. Anderson Summary:,Purpose: Lateralization of language function is crucial to the planning of surgery in children with frontal or temporal lobe lesions. We examined the utility of functional magnetic resonance imaging (fMRI) as a determinant of lateralization of expressive language in children with cerebral lesions. Methods: fMRI language lateralization was attempted in 35 children (29 with epilepsy) aged 8,18 years with frontal or temporal lobe lesions (28 left hemisphere, five right hemisphere, two bilateral). Axial and coronal fMRI scans through the frontal and temporal lobes were acquired at 1.5 Tesla by using a block-design, covert word-generation paradigm. Activation maps were lateralized by blinded visual inspection and quantitative asymmetry indices (hemispheric and inferior frontal regions of interest, at p < 0.001 uncorrected and p < 0.05 Bonferroni corrected). Results: Thirty children showed significant activation in the inferior frontal gyrus. Lateralization by visual inspection was left in 21, right in six, and bilateral in three, and concordant with hemispheric and inferior frontal quantitative lateralization in 93% of cases. Developmental tumors and dysplasias involving the inferior left frontal lobe had activation overlying or abutting the lesion in five of six cases. fMRI language lateralization was corroborated in six children by frontal cortex stimulation or intracarotid amytal testing and indirectly supported by aphasiology in a further six cases. In two children, fMRI language lateralization was bilateral, and corroborative methods of language lateralization were left. Neither lesion lateralization, patient handedness, nor developmental versus acquired nature of the lesion was associated with language lateralization. Involvement of the left inferior or middle frontal gyri increased the likelihood of atypical language lateralization. Conclusions: fMRI lateralizes language in children with cerebral lesions, although caution is needed in interpretation of individual results. [source] Passive Hedge Fund Replication , Beyond the Linear CaseEUROPEAN FINANCIAL MANAGEMENT, Issue 2 2010Noël Amenc G10 Abstract In this paper we extend,Hasanhodzic and Lo (2007),by assessing the out-of-sample performance of various non-linear and conditional hedge fund replication models. We find that going beyond the linear case does not necessarily enhance the replication power. On the other hand, we find that selecting factors on the basis on an economic analysis allows for a substantial improvement in out-of-sample replication quality, whatever the underlying form of the factor model. Overall, we confirm the findings in,Hasanhodzic and Lo (2007)that the performance of the replicating strategies is systematically inferior to that of the actual hedge funds. [source] Repetitive transcranial magnetic stimulation improve tinnitus in normal hearing patients: a double-blind controlled, clinical and neuroimaging outcome studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2010R. A. Marcondes Background and purpose:, Tinnitus is a frequent disorder which is very difficult to treat and there is compelling evidence that tinnitus is associated with functional alterations in the central nervous system. Targeted modulation of tinnitus-related cortical activity has been proposed as a promising new treatment approach. We aimed to investigate both immediate and long-term effects of low frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) in patients with tinnitus and normal hearing. Methods:, Using a parallel design, 20 patients were randomized to receive either active or placebo stimulation over the left temporoparietal cortex for five consecutive days. Treatment results were assessed by using the Tinnitus Handicap Inventory. Ethyl cysteinate dimmer-single photon emission computed tomography (SPECT) imaging was performed before and 14 days after rTMS. Results:, After active rTMS there was significant improvement of the tinnitus score as compared to sham rTMS for up to 6 months after stimulation. SPECT measurements demonstrated a reduction of metabolic activity in the inferior left temporal lobe after active rTMS. Conclusion:, These results support the potential of rTMS as a new therapeutic tool for the treatment of chronic tinnitus, by demonstrating a significant reduction of tinnitus complaints over a period of at least 6 months and significant reduction of neural activity in the inferior temporal cortex, despite the stimulation applied on the superior temporal cortex. [source] Cognitive performance following endarterectomy in asymptomatic severe carotid stenosisEUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2003J. Aharon-Peretz Cognition and the effects of carotid endarterectomy (CEA) were evaluated in 22 non-demented subjects with vascular risk factors (VRF) and asymptomatic severe carotid artery stenosis (ASCAS), 14 volunteers with VRF but without stenosis, and 24 healthy controls (HC) without VRF. Non-demented subjects with VRF, with or without carotid stenosis scored inferior to HC. It is concluded that carotid stenosis is not a primary cause of cognitive deterioration and CEA does not improve cognition in patients with ASCAS. [source] Detection of artificially induced vertical radicular fractures using Tuned Aperture Computed TomographyEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2001Madhu K. Nair This study compared the accuracy of three imaging modalities for the detection of artificially induced vertical root fractures (VRF) on teeth in cadaver mandibles. Fifty-four single-rooted, endodontically treated mandibular teeth being prepared to carry posts were evaluated using direct digital radiography (DDI) with a Schick sensor, unprocessed Tuned Aperture Computed Tomography® (TACT-U) images and iteratively restored TACT (TACT-IR) images. Twenty-eight of these teeth had been subjected to fracture induction using an apically driven force. Nine basis images were used for each TACT image generation. Eight observers used a five-point confidence rating scale to record the confidence with which they considered a fracture to be present or not. Sensitivity and specificity values were computed and receiver operating characteristic (ROC) curves were generated. The areas under the curves (Az) used as an indication of the diagnostic accuracy of the imaging system were as follows: DDI: 0.37; TACT-U: 0.77 and TACT-IR: 0.81. DDI was significantly inferior to the TACT modalities. Differences in detection efficacy based on observers and observation sessions were noted on ANOVA and post-hoc Tukey's tests. This study indicates that TACT is the imaging modality of choice for VRF in endodontically treated teeth. [source] Developing new measures of welfare state change and reformEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 5 2002Francis G. Castles Since the publication of Gøsta Esping,Andersen's The Three Worlds of Welfare Capitalism (Esping,Andersen 1990), which built its typologies on a rich database of detailed programme characteristics, it has been generally accepted that measures of social expenditure are an inferior, and even a misleading, source of information concerning the character of welfare state development. The problem is, however, that the kinds of detailed programme data Esping,Andersen used are not routinely available, while the quality of social expenditure data has been improving rapidly, culminating in the Organisation for Economic Cooperation and Development's (OECD) now regularly updated and highly disaggregated Social Expenditure Database (SOCX). This article explores the possibility of using SOCX to devise measures of the extent, structure and trajectory of welfare state change and reform in 21 OECD countries over the period 1984 to 1997. On the basis of these measures, it suggests that there has been almost no sign of systematic welfare retrenchment in recent years and only limited evidence of major structural transformation or programmatic reorientation. [source] High-resolution estimation for time-variant MIMO channel sounding,EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 7 2008Sofia Martinez Lopez A wideband vector channel sounder with 16 parallel RF chains is proposed for parameter estimation in an indoor channel. Low-cost and high-resolution are obtained by using a chirp probe signal, five-port receivers and the MUSIC algorithm. The system covers up to 500,MHz centred at 2.45,GHz. Experimental results show errors inferior to 1,ns in the time domain and of few degrees in the angular domain. Accurate results are found in static as well as in time-variant scenarios. Copyright © 2008 John Wiley & Sons, Ltd. [source] Mechanical Properties and Environmental Behavior of a Magnesium Alloy with a Nano-/Sub-Micron StructureADVANCED ENGINEERING MATERIALS, Issue 9 2007E. Aghion Abstract Newly developed magnesium alloys with a consolidated nano/sub-micron structure and substantially higher specific strength may be considered as an interesting candidate for super-light high-strength applications. Consolidated nano/sub-micron structure applies to alloys with a combined microstructure of nano-crystalline and sub-micron grains. The aim of the present study was to explore the mechanical and environmental behavior of a consolidated nano/sub-micron magnesium alloy with the composition of AZ31. This was required in order to evaluate the applicability of this new structured alloy for practical applications. Although the nano/sub-micron structured alloy has more than twice the hardness and strength of the conventional alloy, its ductility and corrosion resistance were significantly lower. In addition, its stress corrosion characteristics were inferior. The significant limitation of the nano-structured alloy, in terms of ductility and corrosion performance, restricts its potential use as a structural material for practical applications. [source] Open-Economy Inflation-Forecast TargetingGERMAN ECONOMIC REVIEW, Issue 1 2006Kai Leitemo Inflation targeting; forecast targeting; monetary policy; small open economy Abstract. We study simple inflation-forecast targeting in an open-economy setting. Simple inflation-forecast targeting implies setting an interest rate which, if kept unchanged throughout the forecast-targeting horizon, produces a conditional inflation forecast equal to the inflation target at the end of the horizon. We find that the optimal forecast-targeting horizon is relatively short (one year). A longer horizon does not consistently contribute to improved output stability, indeed it increases exchange rate variability and traded sector variability. The targeting procedure is substantially inferior to the optimal pre-commitment policy. Moreover, the targeting procedure does not necessarily determine the rational-expectations equilibrium and is subject to time inconsistency. [source] Canadian multi-institutional survey of immune tolerance therapy (ITT) , experience with the use of recombinant factor VIII for ITTHAEMOPHILIA, Issue 1 2006C. BARNES Summary., Immune tolerance therapy (ITT) is currently the most effective approach to eradicate inhibitors in patients with haemophilia A. Limited evidence suggests that the use of plasma-derived factor VIII (pdFVIII) for ITT may be associated with a greater success rate than recombinant factor VIII (rFVIII). Analysis of ITT cases in Canada offered the opportunity to examine the success rate of using rFVIII for ITT, as rFVIII has been used almost exclusively for Canadian haemophilia A patients since 1994. The results of 32 patients from five haemophilia treatment centres were collated. Three patients continue on ITT. Of the 29 patients who completed ITT, 25 (86.2%) used rFVIII exclusively, and four used pdFVIII exclusively or pdFVIII followed by rFVIII. The initial FVIII dosing frequency was once per day in 72.4% of patients at an average dose of 98 U kg,1 (range 50,200). Eight patients (25%) received one or more adjuvant therapies. The median duration of ITT was 1.1 years (mean 1.5 years, range 9 days to 6 years). The overall success rate of the 29 patients who completed ITT was 79.3% (23/29), which is comparable with the results of immune tolerance registries. Our results suggest that the success rate of ITT using rFVIII is not inferior to the results with pdFVIII. [source] Ownership,efficiency relationship and the measurement selection biasACCOUNTING & FINANCE, Issue 5 2006Richard Bozec G32; H11; L33 Abstract This study analyses the bias in the selection of performance measures for ownership comparisons, which depends on the specific objectives of the firms being compared. Our sample includes 13 Canadian state-owned enterprises (SOEs), commercialized and/or privatized between 1976 and 2001. To replace profitability measures and reduce biases, we propose the use of technical efficiency, which provides for SOEs' specificities. Overall, the results clearly support the view that privatization has no impact on a firm's technical efficiency, the only positive impact being related to a change in the objectives of the firm while using profitability measures. The results of this study raise the question of the validity of comparisons between SOEs and private firms when using profitability indicators. The potential bias in favour of the private firms contributes to a misleading image of the public sector being presented as inferior and inefficient. The use of more sophisticated measures, such as data envelopment analysis, suggests conflicting conclusions. This study also casts doubt on the legitimacy of the privatization program initiated around the world and more specifically in Canada in which the main justification for such a reform has been to increase the performance of SOEs. [source] Interorgan ammonia and amino acid metabolism in metabolically stable patients with cirrhosis and a TIPSSHEPATOLOGY, Issue 5 2002Steven W. M. Olde Damink Ammonia is central to the pathogenesis of hepatic encephalopathy. This study was designed to determine the quantitative dynamics of ammonia metabolism in patients with cirrhosis and previous treatment with a transjugular intrahepatic portosystemic stent shunt (TIPSS). We studied 24 patients with cirrhosis who underwent TIPSS portography. Blood was sampled and blood flows were measured across portal drained viscera, leg, kidney, and liver, and arteriovenous differences across the spleen and the inferior and superior mesenteric veins. The highest amount of ammonia was produced by the portal drained viscera. The kidneys also produced ammonia in amounts that equaled total hepatosplanchnic area production. Skeletal muscle removed more ammonia than the cirrhotic liver. The amount of nitrogen that was taken up by muscle in the form of ammonia was less than the glutamine that was released. The portal drained viscera consumed glutamine and produced ammonia, alanine, and citrulline. Urea was released in the splenic and superior mesenteric vein, contributing to whole-body ureagenesis in these cirrhotic patients. In conclusion, hyperammonemia in metabolically stable, overnight-fasted patients with cirrhosis of the liver and a TIPSS results from portosystemic shunting and renal ammonia production. Skeletal muscle removes more ammonia from the circulation than the cirrhotic liver. Muscle releases excessive amounts of the nontoxic nitrogen carrier glutamine, which can lead to ammonia production in the portal drained viscera (PDV) and kidneys. Urinary ammonia excretion and urea synthesis appear to be the only way to remove ammonia from the body. [source] Medial temporal lobe activity at recognition increases with the duration of mnemonic delay during an object working memory taskHUMAN BRAIN MAPPING, Issue 11 2007Marco Picchioni Abstract Object working memory (WM) engages a disseminated neural network, although the extent to which the length of time that data is held in WM influences regional activity within this network is unclear. We used functional magnetic resonance imaging to study a delayed matching to sample task in 14 healthy subjects, manipulating the duration of mnemonic delay. Across all lengths of delay, successful recognition was associated with the bilateral engagement of the inferior and middle frontal gyri and insula, the medial and inferior temporal, dorsal anterior cingulate and the posterior parietal cortices. As the length of time that data was held in WM increased, activation at recognition increased in the medial temporal, medial occipito-temporal, anterior cingulate and posterior parietal cortices. These results confirm the components of an object WM network required for successful recognition, and suggest that parts of this network, including the medial temporal cortex, are sensitive to the duration of mnemonic delay. Hum Brain Mapp 2007. © 2006 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||