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A five-year-old boy presented with left tibial swelling; there was a typical radiological feature of osteofibrous dysplasia. He was observed until the age of 14 years; there was development of aggressive radiological features. Biopsy revealed chondroblastic osteosarcoma. It was excised and the histology revealed chondroblastic osteosarcoma. A small lesion distal to the main tumour revealed adamantinoma within a background of feature of osteofibrous dysplasia. Proximally, feature of osteofibrous dysplasia was identified focally. The finding of adamantinoma over the distal part of the lesion supports that feature of osteofibrous dysplasia may be a precursor of adamantinoma. They may be a spectrum of diseases with multistep neoplastic transformation. The osteosarcoma may be a result of de-differentiation from adamantinoma. This case is remarkable as the patient was only 14 years old and the tumour showed typical features of osteosarcoma, with feature of osteofibrous dysplasia and adamantinoma found in the same specimen. Feature of osteofibrous dysplasia may be a precursor of adamantinoma, and adamantinoma may dedifferentiate into osteosarcoma.

With the colliding global epidemics of diabetes mellitus (DM) and tuberculosis (TB), we studied the effects of DM on the presentation of TB and its response to treatment.Consecutive TB patients from 2006 to 2010 in a territory-wide treatment programme offering 9-month extended treatment for TB patients with DM were examined and followed up prospectively to assess their treatment response. Successful treatment completers were tracked through the TB registry and death registry for relapse, death or till 31 December 2014, whichever was the earliest.DM was independently associated with more chest symptoms (adjusted OR (AOR): 1.13) and systemic symptoms (AOR: 1.30) but less with other site-specific symptoms (AOR: 0.58) at TB presentation. There was more frequent pulmonary involvement (AOR: 1.69), with more extensive lung lesion (AOR: 1.25), lung cavity (AOR: 2.00) and positive sputum smear (AOR: 1.83) and culture (AOR: 1.38), but no difference in the proportion of retreatment cases or isoniazid and/or rifampicin resistance. After treatment initiation, there was higher overall incidence (AOR: 1.38) of adverse effects (mainly gastrointestinal symptoms, renal impairment and peripheral neuropathy but less fever and skin hypersensitivity reactions), more smear non-conversion (AOR: 1.59) and culture non-conversion (AOR: 1.40) at 2 months, and lower combined cure/treatment completion rate at 12 months (AOR: 0.79), but no difference in the relapse rate after having successfully completed treatment.DM adversely affected the clinical presentation and treatment response of TB, but there was no difference in the drug resistance and relapse rates.

There are fixed costs in production. One has to assemble rents earned in production lines to cover them. There are also fixed costs in consumption. Consumers assemble surpluses to cover them. In either case, rent assemblage could either be a quantity solution, a quality solution, or a combination of both. Once a fixed cost is committed by contract, it becomes historical. Yet compared to the option of paying this fixed cost all over again, increasing those quantities or qualities, which do not further increase this fixed cost, is less costly. The Law of Demand therefore implies the quality and/or the quantity solutions. The quality solution, as provided by the Alchian-Allen Theorem, is but a special case: where an increase in quality is the only viable solution under some specific real world constraints.

In the present paper, effects of through-the-thickness stitching of delaminated glass/epoxy composite laminates with two different types of aramid threads, Kevlar® and Twaron® threads, on the buckling loads are studied. The buckling loads are predicted based on the Southwell, Vertical displacement and Membrane strain plot methods from the experimental data. Flexural modulus of the stitched and unstitched glass/epoxy composite laminates, knot tensile strength of Kevlar® and Twaron® stitching threads are obtained experimentally. From the Southwell, Vertical displacement and Membrane strain plot methods it is observed that stitching either by Kevlar® or Twaron® threads is effective in improving the buckling strength of glass/epoxy composite laminates when the delamination length is greater than 0.5L, L is the length of the laminate.

In the current investigation, effects of through-the-thickness stitching with two different types of aramid threads, Kevlar® and Twaron® threads, on the buckling loads of delaminated glass/epoxy composite laminates are studied. Buckling loads are predicted based on the Southwell, Vertical displacement and Membrane strain plot methods by using the experimental data. From the Southwell, Vertical displacement and Membrane strain plot methods it is observed that stitching either by Kevlar® or Twaron® threads is effective in improving the buckling strength of glass/epoxy composite laminates when the delamination length is greater than 0.5L, L being the length of the laminate. For long delaminations, Kevlar® stitched glass/epoxy composite laminate is best in retaining its buckling strength when re-loading is done. Southwell plot method tends to overestimate the buckling loads as the data obtained from this method are influenced by the breakages in the glass/epoxy composite laminate buckling test specimens.

Background Use of remifentanil during general anesthesia for cesarean delivery has been described, but its maternal and neonatal effects have not been investigated by a controlled study. Methods In a randomized, double-blind, controlled study, patients undergoing elective cesarean delivery received an intravenous bolus of 1 microg/kg remifentanil (n = 20) or saline (n = 20) immediately before induction of general anesthesia. The authors compared maternal hemodynamic changes and neonatal condition and measured plasma concentrations of remifentanil. Results The maximum increase in systolic arterial pressure from baseline after induction was smaller in the remifentanil group (median, 9 [range, -17 to 31] mmHg) compared with the control group (42 [6-73] mmHg, median difference, 33 mmHg; 95% confidence interval of difference, 23-45 mmHg; P < 0.0001). Maximum recorded values were smaller in the remifentanil group compared with the control group for systolic and mean arterial pressure and maternal heart rate. Apgar scores and time to sustained respiration were similar between groups. Two neonates in the remifentanil group were considered clinically depressed at birth and were given a single dose of naloxone. Remifentanil crossed the placenta with an umbilical venous/maternal arterial concentration ratio of 0.73 (SD, 0.17) and an umbilical arterial/umbilical venous concentration ratio of 0.60 (0.23). Conclusions A single bolus of 1 microg/kg remifentanil effectively attenuated hemodynamic changes after induction and tracheal intubation. However, remifentanil crosses the placenta and may cause mild neonatal depression and thus should be used for clear maternal indications when adequate facilities for neonatal resuscitation are available.

This nested case-control study aimed at evaluating treatment-related risk factors of relapse of tuberculosis under a service program of directly observed treatment. Out of 12,183 patients with pulmonary tuberculosis who completed treatment within 1 year, 113 relapsed within 30 months after commencement of therapy. The overall 30-month relapse rate was 0.9% (95% confidence interval [CI] 0.8-1.1%). On matching 113 cases with 226 control subjects in a conditional logistic model, thrice-weekly treatment increased the risk of relapse in comparison with daily treatment (odds ratio 3.92, 95% CI 1.78-8.63), whereas prolonging both intensive phase and overall treatment by 50% or more protected against relapse (odds ratio 0.24, 95% CI 0.08-0.70). When pretreatment culture was positive and cavitation was absent, the 30-month relapse rate for standard thrice-weekly regimen was 1.1% (95% CI 0.6-2.0%). The corresponding rates in the presence of cavitation were 7.8% (95% CI 4.0-14.6%) for standard thrice-weekly regimen; 3.3% (95% CI 1.9-5.5%) for standard daily regimen; 0.5% (95% CI 0.1-2.6%) for extended thrice-weekly regimen; and 0.4% (95% CI 0.1-0.9%) for extended daily regimen. Further studies are required to reduce the risk of relapse under program settings.

Here we contrast the stability of monomeric and photopolymerized self-assembled monolayers (SAMs) containing a diacetylene group (HS(CH2)10C⋮CC⋮C(CH2)10COOH) with SAMs prepared from simple n-alkanethiols. The polymerized SAMs are extremely durable compared to either the n-alkanethiol SAMs or the unpolymerized diacetylenic SAMs. For example, they are stable to repeated electrochemical cycling to extreme potentials, thermal excursions to 200 °C, and exposure to hot base (1:1 mixture of ethanol and 1.0 M aqueous KOH at 100 °C). All of these conditions completely strip n-alkanethiol SAMs from Au substrates. These high-performance materials are suitable for applications in lubrication, adhesion, corrosion passivation, and chemical sensing.

Here we discuss the preparation and characterization of photopolymerizable, self-assembled monolayers (SAMs) that consist of acid-, hydroxyl-, and methyl-terminated n-alkanethiols containing a diacetylene group (HS(CH2)10C⋮CC⋮C(CH2)10X; X = COOH, CH2OH, and CH3, respectively). The acid and hydroxyl surfaces are readily amenable to further synthetic elaboration, while the methyl-terminated SAM results in a clean, low-energy surface. As demonstrated by Fourier transform infrared external reflectance spectroscopy (FTIR-ERS), surface-enhanced Raman spectroscopy (SERS), ellipsometry, UV−vis spectroscopy, and electrochemical methods, all three materials self assemble onto Au surfaces to form ordered monolayers that can be photopolymerized with UV light.

Issue addressed: This study aimed to examine the participation of Australian Chinese in cardiovascular risk factor and cancer screening. Methods: A telephone survey of a random sample of Chinese in New South Wales, Australia, was conducted. The presence of, and participation in screening for, hypertension, hyperlipidaemia and diabetes were ascertained. Additionally, women were surveyed regarding breast cancer and cervical cancer screening. Results: Five hundred and fifty-five subjects were interviewed. Generally, Australian Chinese were as likely to participate in health screening activities as the general population. However, Chinese with poor English-speaking ability were less likely to have had recent lipid testing (85.4% vs 91.2%, p=0.01) or mammography (63.2% vs 92.6%, p=0.01) than those who were proficient in English (adjusted for age and gender). Those not in employment were less likely to have had lipid testing (86.9% vs 88.4%, p=0.04), mammography (61.1% vs 93.5%, p=0.04) or Pap tests (64.7% vs 85.0%, p

This paper is a study of digital identity management system with specific emphasis on its implementation using a set of credentials. In our study we propose a credentials attributes mapping technique, the so-called common attributes mapping (CaMa) which facilitates the extraction of useful features to be represented in composing an identity. The study also groups credentials of similar types and information from them are fused and used as the set of discriminators which facilitate online identity of users. Using artificial neural networks, face recognition and fingerprint recognition, a digital environment identity (DEITY) is developed in .NET and tested. The system is effective in providing both the identities of the person and the equipment being used for online access.

The optimal approach for reducing tuberculosis relapse is open.We examined the possibility of reducing relapse by increasing dosing schedules.We conducted a systematic review of published clinical trials involving adult cohorts with pulmonary tuberculosis treated using 6-mo rifamycin-containing regimens, which were grouped under seven categories ordered by dosing schedules. Assuming cavitation and positive 2-mo culture were the driving forces for relapse, a static deterministic model apportioned observed numbers with and without relapse in each cohort into eight subgroups. Combining subgroups stratified by cavitation, 2-mo culture, and regimens enabled estimation of adjusted relapse risks. chi2 Tests for trend and logistic regression analysis examined the relationship between relapse and dosing schedules.We identified 200 cases of bacteriologic relapse out of 5,208 patients in 32 cohorts. A logistic risk model showed a significant dose-response relationship between dosing schedules and relapse, with the following odds (95% confidence intervals) of relapse relative to daily regimens: 1.6 (0.6-4.1) for daily initial phase (IP) plus thrice-weekly continuation phase (CP), 2.8 (1.3-6.1) for daily IP plus twice-weekly CP, 2.8 (1.4-5.7) for thrice-weekly, 5.0 (2.4-10.5) for daily IP plus once-weekly rifapentine, and 7.1 (3.3-15.3) for thrice-weekly IP plus once-weekly rifapentine. In the presence of cavitation, only 6-mo daily or daily IP plus thrice-weekly CP attained best-estimated relapse risks below 5%; they reached 6% when 2-mo culture was also positive.Cavitary tuberculosis is best treated with 6-mo regimens comprising daily IP and thrice-weekly CP, which may be extended when 2-mo culture is positive.

Use of remifentanil during general anesthesia for cesarean delivery has been described, but its maternal and neonatal effects have not been investigated by a controlled study.In a randomized, double-blind, controlled study, patients undergoing elective cesarean delivery received an intravenous bolus of 1 microg/kg remifentanil (n = 20) or saline (n = 20) immediately before induction of general anesthesia. The authors compared maternal hemodynamic changes and neonatal condition and measured plasma concentrations of remifentanil.The maximum increase in systolic arterial pressure from baseline after induction was smaller in the remifentanil group (median, 9 [range, -17 to 31] mmHg) compared with the control group (42 [6-73] mmHg, median difference, 33 mmHg; 95% confidence interval of difference, 23-45 mmHg; P0.0001). Maximum recorded values were smaller in the remifentanil group compared with the control group for systolic and mean arterial pressure and maternal heart rate. Apgar scores and time to sustained respiration were similar between groups. Two neonates in the remifentanil group were considered clinically depressed at birth and were given a single dose of naloxone. Remifentanil crossed the placenta with an umbilical venous/maternal arterial concentration ratio of 0.73 (SD, 0.17) and an umbilical arterial/umbilical venous concentration ratio of 0.60 (0.23).A single bolus of 1 microg/kg remifentanil effectively attenuated hemodynamic changes after induction and tracheal intubation. However, remifentanil crosses the placenta and may cause mild neonatal depression and thus should be used for clear maternal indications when adequate facilities for neonatal resuscitation are available.

In many cone beam reconstruction algorithms square geometry for the detector elements and cubic geometry for the reconstruction voxels are assumed. With such geometry the various operations in image reconstruction, notably projection and backprojection, can be carried out in the same manner at all angles, resulting in uniform image quality and ease of operation. However, in current multi-row cone beam CT systems the spacing between the detector rows is typically greater than the lateral spacing between the detector elements for the reconstruction of objects with slice thickness greater than the lateral resolutions. The asymmetric voxel dimensions and detector element dimensions introduce complications in the image reconstruction operations, and potentially non-uniform image quality. We have developed a procedure to preprocess the cone beam data detected on non-square detector elements for compatibility with cone beam reconstruction algorithms in which symmetric voxel dimensions and detector element dimensions are assumed. Complications and potential non-uniformity in image reconstruction operations are eliminated through simple scaling of the input cone beam projection data and decompression/elongation of the intermediate reconstructed image while retaining the symmetric geometry in the reconstruction algorithm. The procedure is a generic solution to cone beam image reconstruction applicable to all types of reconstruction algorithms.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In the long object problem it is intended to reconstruct exactly a region-of-interest (ROI) of an object from spiral cone beam data which covers the ROI and its nearest vicinity only. In the first paper in a series of two the theory of the local ROI method is derived using the filtered-backprojection approach. In the present second paper the demanding numerical implementation is described. The straightforward 4-step algorithm is applied. It mainly consists of explicit calculations of the derivatives of partial plane integrals of the object from line segments in the projection images. In the local ROI method grouping of line segments to particular (phi) -planes in 3-D Radon space is important. A rigorous grouping causes artifacts which can be avoided by a fuzzy correspondence of line segments to (phi) -planes. In the ROI the same image quality is achieved for a partial scan as for a full scan. However, the method suffers from high computational requirements. The filtering step can be speeded up by replacing the 4-step algorithm by convolution with spatially variant 1-D Hilbert transforms. An in-depth analysis of the empirical PSF of detector pixels filtered by the 4-step algorithm confirmed the theoretical results. Modifications for practical implementation are outlined which are subject to further investigations.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A recently published local region-of-interest (ROI) technique makes it possible to image a ROI in a long object in cone beam spiral scans without blurring from the overlaying materials; the local ROIs refer to the portions of the object bounded by the parallel projections of the spiral scan path on the (phi) planes in the Radon space. First, the Radon derivative data for the local ROIs are computed from the cone beam data; second, the local ROIs are reconstructed; and finally the ROI is reconstructed from the local ROIs. For any cone beam image detected near the top and the bottom of the spiral path, the integration line segments are limited in different manners depending on whether the local ROI projects onto the corresponding (phi) plane on the uppermost/lowermost complete stage of the projected spiral or not. In this first part in a series of two papers reformulating the local ROI method into a filtered backprojection (FBP)-based algorithm, the theoretical derivation of the FBP-based local ROI method is presented, and the demanding numerical implementation together with the simulation results are reported in the second paper. We have developed a simple procedure to group line segments for the filtering operation according to the manner they are limited. Furthermore, it is found that the filtering operation on the cone beam images is equivalent to a number of 1D Hilbert transforms followed by 1D differentiation in the projected scan path direction.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We present a spiral scan cone beam reconstruction algorithm in which image reconstruction proceeds via backprojection in the object space. In principle the algorithm can reconstruct sectional ROI in a long object. The approach is a generalization of the cone beam backprojection technique developed by Kudo and Saito in two aspects: the resource- demanding normalization step in the Kudo and Saito's algorithm is eliminated through the technique of data combination which we published earlier, and the elimination of the restriction that the detector be big enough to capture the entire image of the ROI. Restricting the projection data to the appropriate angular range required by data combination can be accomplished by a masking process. The mask consists of a top curve and a bottom curve formed by projecting the spiral turn above and the turn below from the current source position. Because of the simplification resulting from the elimination of the normalization step, the most time-consuming operations of the algorithm can be approximated by the efficient step of line-by-line ramp filtering the cone beam image in the direction of the scan path, plus a correction term. The correction term is needed because data combination is not properly matched at the mask boundary when ramp filtering is involved. This correction term to the mask boundary effect can be computed exactly. The results of testing the algorithm on simulated phantoms are presented.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A method is developed which makes it possible to scan and reconstruct an object with cone beam x-ray in a spiral scan path with area detectors much shorter than the length of the object. The method is mathematically exact. If only a region- of-interest of the object is to be imaged, a top circle scan at the top level of the region-of-interest and a bottom circle scan at the bottom level of the region-of-interest are added. The height of the detector is required to cover only the distance between adjacent turns in the spiral projected at the detector. To reconstruct the object, the Radon transform for each plane intersecting the object is computed from the totality of the cone beam data. This is achieved by suitably combining the cone beam data taken at different source positions on the scan path; the angular range of the cone beam data required at each source position can be determined easily with a mask which is the spiral scan path projected on the detector from the current source position. The spiral scan algorithm has been successfully validated with simulated cone beam data.

We consider the elastic scattering of low-energy electrons by neutral donor impurities in silicon, taking account of the actual anisotropic many-valley conduction band. Necessary modifications of the standard formulas of elastic-scattering theory that result from band anisotropy are derived. S matrices are determined by the solution of a set of coupled differential equations in which the static Coulomb potential and approximate representations of exchange and polarization interactions appear. The scattering is strongly anisotropic and spin dependent, even at very low energies.

Calcul des sections efficaces de l'excitation d'impact des electrons des etats d'impuretes neutres de decomposition d'orbite de vallee dans la premiere approximation de Born pour des energies superieures et inferieures a l'energie d'ionisation de l'impurete. Le modele prend en compte la structure de bande de conduction a minimum multiple et la possibilite de diffusion intervallee

We report herein that a substrate can be patterned using a diacetylenic, self-assembled monolayer (SAM) resist and photolithographic and electrochemical methods. Our proof-of-concept experiments result in micron-scale pattern transfer onto Au substrates, but extension to other materials, including Si, Al, and GaAs, and nanometer-scale patterning will be straightforward. It is demonstrated that a SAM composed of diacetylenic organomercaptans can be used as a negative photolithographic resist. The importance of this method results from the fact that the resist is highly organized, thin, and largely defect free. These factors ensure high-resolution patterning and control over the surface energy and reactivity of the resist itself, which permits an added dimension of control over surface processing. In addition, resist stripping involves only gentle and easily controlled electrochemical methods. Moreover, we have previously shown that organized multilayers of polydiacetylenic SAMs can be easily formed, so resist thickness can be controlled over a broad range. Finally, unique electronic and photonic properties of the polymeric SAMs might themselves be integrated into Si-based devices using this lithographic approach in the future. 34 refs., 2 figs.

This reprint shows self-consistent, spin-polarized calculations for free Fe13, Ni13, and Ni19 clusters with face-centered-cubic geometry and for a Fe14 C cluster with body-centered-cubic geometry. The calculations are made by expansion in a basis set of Gaussian orbitals. Results are discussed in relation to similiar calculations for bulk metals. Comparison of the present results with out previous calculations for Fe15 shows that the d-level distribution in the nickel cluster is narrower in comparison with the bulk that is found for iron, but that the spin distribution is closer to the bulk. The central atom in the Fe13 cluster is strongly spin polarized oppositely to the surrounding atoms. Effects due to replacement of the central iron atom in Fe15 by carbon are studied. The ionization potential of Fe14 was found to be 5.41 eV. Additional keywords: electronic states; excitation.

The use of the peripheral nerve stimulator is essential for adequate assessment of the degree of neuromuscular block. To ensure that the data derived are accurate one must understand the effects of stimulus frequency, electrode type, position and polarity, stimulus intensity, duration, waveform and the various ways used to observe the data, electromechanical, EMG, tactile or visual. Once these features are understood, a better interpretation of the various tests is possible. While a lot of information regarding the proper use of the PNS is derived from meticulous scientific experimentation, it is possible to apply this information for clinical use. Most information is available based on ulnar nerve stimulation. Information on stimulation of other nerves (e.g., current to achieve SMS on the peroneal nerve) is lacking. With this in mind, the authors present in Table III the minimum requirements for a PNS and an algorithm to illustrate use of the PNS, in Figure 6.

To lessen the risks associated with cannulation of the internal jugular vein, a method to identify the contours of the carotid artery and internal jugular vein at the site of cannulation is proposed. This method uses a doppler flow detector equipped with an adjustable electronic filter which selectively enhances the sound component due either to the arterial or venous flow. This method has been applied clinically and was found to be useful in the identification of the vessels. Since doppler flow detectors are readily available in many hospitals and the required modification is simple, we hope that other institutions will find this technique useful in their clinical practice.

A new design - fully three dimensional -Positron Camera is presented, made of six MultiWire Proportional Chamber modules arranged to form the lateral surface of a hexagonal prism. A true coincidence rate of 56000 c/s is expected with an equal accidental rate for a 400 iCi activity uniformly distributed in a --3k water phantom. A detailed Monte Carlo program has been used to investigate the dependence of the spatial resolution on the geometrical and physical parameters. A spatial resolution of 4.8 mm FWHM has been obtained for a 18F point-like source in a 10 cm radius water phantom. The main properties of the limited angle reconstruction algorithms are described in relation to the proposed detector geometry.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

I would like to thank Prof. Pedersen for his interest in the paper that the late Dr. Bhattacharyya and I coauthored more than a decade ago.