306 research outputs found

    Physician and nurse knowledge about patient radiation exposure in the emergency department

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    Background: Imaging methods that use ionizing radiation in emergency departments (EDs) have increased with advances in radiological diagnostic methods. Physician and nurse awareness of the radiation dose in the ED and the associated cancer risks to which the patients are exposed were surveyed with a questionnaire.Methods: A total of 191 subjects in six EDs participated in this study. ED physicians and ED nurses were asked about the risks and the radiation doses of imaging methods ordered in the ED. The differences between the two groups were compared using Student’s t‑test for continuous variables. A Fisher’s exact and Chi‑squared tests were used for categorical variables.Results: A total of 82 ED physicians and 109 ED nurses completed the questionnaire; 38 (46.3%) physicians and 8 (7.3%) nurses correctly answered the question about the chest X‑ray radiation dose. A question about the number of chest X‑rays that is equivalent to the dose of a pelvic X‑ray was answered correctly by 5 (6.1%) physicians and 9 (8.3%) nurses (P = 0.571). Questions regarding abdominal computed tomography (CT), chest CT, brain CT, abdominal ultrasonography, and brain magnetic resonance imaging were answered correctly more frequently by the physician group than the nurse group (P < 0.05). The risk of developing cancer over a lifetime due to a brain CT was correctly answered by 21 (25.6%) physicians and 30 (27.5%) nurses (P = 0.170). A similar question regarding abdominal CT was correctly answered by 21 (25.6%) physicians and 42 (38.5%) nurses (P = 0.127).Conclusions: Knowledge of the radiation exposure of radiology examinations was lower in nurses than physicians, but knowledge was poor in both groups. ED physicians and nurses should be educated about radiation exposure and cancer risks associated with various diagnostic radiological methods.Keywords: Diagnostic imaging, emergencies, radiation dosag

    The clinical usefulness of initial serum procalcitonin as an aggravation predictor in a hepatobiliary tract infection at emergency department

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    Background and Objectives: The ability to predict future clinical deterioration early in patients who present to an emergency care center with a hepatobiliary tract infection is difficult. We studied the clinical usefulness of the initial serum levels of procalcitonin in a hepatobiliary tract infection as an indicator for predicting aggravation in the early stages.Methods: Of the patients who presented with the clinical symptoms of a hepatobiliary tract infection, 99 were diagnosed with a hepatobiliary tract infection by imaging studies and subsequently enrolled in the study. Laboratory tests were obtained in the early stage of disease after presentation to an emergency care center. We assessed and compared the serum levels of many early inflammatory markers (white blood cell [WBC] counts, C‑reactive protein and procalcitonin) between patients whose symptoms were initially stable upon arrival to an emergency care center but then deteriorated to, those whose symptoms remained consistently stable. Thus, we examined if the above serum markers are useful in predicting the possibility of future symptom aggravation.Results: Of a total of 99 patients, 27 were assigned to the symptom aggravation group. The serum levels of WBC counts and C‑reactive protein in the aggravation group were elevated. However, the median value (interquartile range) of procalcitonin was relatively increased at 2.28 (0.41–7.84 ng/ml), demonstrating a significant difference.Conclusions: In conclusion, initial serum levels of procalcitonin might be used as an indicator for aggravation in patients with hepatobiliary tract infection at the emergency department, even though there is hemodynamic stability.Key words: Hepatobiliary tract, infection, procalcitoni

    An artifacts removal post-processing for epiphyseal region-of-interest (EROI) localization in automated bone age assessment (BAA)

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    <p>Abstract</p> <p>Background</p> <p>Segmentation is the most crucial part in the computer-aided bone age assessment. A well-known type of segmentation performed in the system is adaptive segmentation. While providing better result than global thresholding method, the adaptive segmentation produces a lot of unwanted noise that could affect the latter process of epiphysis extraction.</p> <p>Methods</p> <p>A proposed method with anisotropic diffusion as pre-processing and a novel Bounded Area Elimination (BAE) post-processing algorithm to improve the algorithm of ossification site localization technique are designed with the intent of improving the adaptive segmentation result and the region-of interest (ROI) localization accuracy.</p> <p>Results</p> <p>The results are then evaluated by quantitative analysis and qualitative analysis using texture feature evaluation. The result indicates that the image homogeneity after anisotropic diffusion has improved averagely on each age group for 17.59%. Results of experiments showed that the smoothness has been improved averagely 35% after BAE algorithm and the improvement of ROI localization has improved for averagely 8.19%. The MSSIM has improved averagely 10.49% after performing the BAE algorithm on the adaptive segmented hand radiograph.</p> <p>Conclusions</p> <p>The result indicated that hand radiographs which have undergone anisotropic diffusion have greatly reduced the noise in the segmented image and the result as well indicated that the BAE algorithm proposed is capable of removing the artifacts generated in adaptive segmentation.</p

    Bioinformatics research in the Asia Pacific: a 2007 update

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    We provide a 2007 update on the bioinformatics research in the Asia-Pacific from the Asia Pacific Bioinformatics Network (APBioNet), Asia's oldest bioinformatics organisation set up in 1998. From 2002, APBioNet has organized the first International Conference on Bioinformatics (InCoB) bringing together scientists working in the field of bioinformatics in the region. This year, the InCoB2007 Conference was organized as the 6th annual conference of the Asia-Pacific Bioinformatics Network, on Aug. 27–30, 2007 at Hong Kong, following a series of successful events in Bangkok (Thailand), Penang (Malaysia), Auckland (New Zealand), Busan (South Korea) and New Delhi (India). Besides a scientific meeting at Hong Kong, satellite events organized are a pre-conference training workshop at Hanoi, Vietnam and a post-conference workshop at Nansha, China. This Introduction provides a brief overview of the peer-reviewed manuscripts accepted for publication in this Supplement. We have organized the papers into thematic areas, highlighting the growing contribution of research excellence from this region, to global bioinformatics endeavours

    Sequential chemotherapy and intensity-modulated radiation therapy in the management of locoregionally advanced nasopharyngeal carcinoma: Experience of 370 consecutive cases

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    <p>Abstract</p> <p>Introduction</p> <p>To investigate the outcome of locoregionally advanced nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT) after induction chemotherapy, with or without concomitant chemotherapy.</p> <p>Methods</p> <p>Between August 2003 and March 2007, 370 patients with locoregionally advanced NPC were treated with IMRT. Presenting stages were stage IIB in 62, stage III in 197, and stage IVA/B in 111 patients. All patients except for 36 patients with cervical lymphadenopathy of 4 cm or less in diameter received 2 cycles of cisplatin-based neoadjuvant chemotherapy. Forty-eight patients received cisplatin-based concurrent chemotherapy as well.</p> <p>Results</p> <p>With a median follow-up time of 31 months (range 5 to 61 months), the 3-year local control, regional control, metastasis-free survival (MFS), disease-free survival (DFS) and overall survival (OS) rates were 95%, 97%, 86%, 81% and 89%, respectively. Multivariate analyses revealed that both age (≤ 60 vs. >60) and N-classification are significant prognosticators for OS (P = 0.001, hazard ratio [HR] 2.395, 95% confidence interval [CI] 1.432-4.003; P = 0.012, hazard ratio [HR] 2.614, 95% confidence interval [CI] 1.235-5.533); And N-classification is the only significant predicative factor for MFS (P = 0.002, [HR] 1.99, 95% CI 1.279-3.098). T-classification and concurrent chemotherapy were not significant prognostic factors for local/regional control, MFS, DFS, or OS. Subgroup analysis revealed that concurrent chemotherapy provided no significant benefit to IMRT in locoregionally advanced NPC, but was responsible for higher rates of grade 3 or 4 acute toxicities (50% vs. 29.8%, P < 0.005). No grade 3 or 4 late toxicity including xerostomia was observed. However, two patients treated with IMRT and neoadjuvant but without concurrent and adjuvant chemotherapy died of treatment related complications.</p> <p>Conclusion</p> <p>IMRT following neoadjuvant chemotherapy produced a superb outcome in terms of local control, regional control, MFS, DFS, and OS rates in patients with stage IIB to IVB NPC. Effective treatment strategy is urgently needed for distant control in patients diagnosed with locoregionally advanced NPC.</p

    Effects of CuO additives and sol-gel technique on NiNb2O6 dielectric ceramics for LTCC application

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    The effects of CuO additives and sol–gel method synthesis on the sintering behavior, microstructure and the microwave dielectric properties of NiNb2O6 ceramics were investigated systematically. The NiNb2O6 ceramics were synthesized with traditional solid state method and sol–gel method, and the CuO additives were used in the solid state method for comparison. The sintering temperature of NiNb2O6 ceramics with the highest densification can be effectively reduced from about 1275 °C to 1050 and 1100 °C respectively by using CuO additions and sol–gel technique. To study their applicability in low temperature co-fired ceramic technology, dielectric properties have been characterized. The dielectric properties exhibited a significant dependence on the sintering condition, composition and crystal structure of the ceramics. In particular, the 2.5 wt% CuO-doped NiNb2O6 ceramics sintered at 1050 °C have excellent microwave dielectric properties: εr = 21.45, Q × f = 23,531 GHz, τf = −27.9 ppm/°C. While the NiNb2O6 ceramics prepared by sol–gel method obtain microwave dielectric properties as: εr = 19.16, Q × f = 11,149 GHz, τf = −27.3 ppm/°C after sintered at 1100 °C for 2 h

    Sensorineural hearing loss after concurrent chemoradiotherapy in nasopharyngeal cancer patients

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    <p>Abstract</p> <p>Background</p> <p>Sensorineural hearing loss (SNHL) is one of the major long term side effects from radiation therapy (RT) in nasopharyngeal cancer (NPC) patients. This study aims to review the incidences of SNHL when treating with different radiation techniques. The additional objective is to determine the relationship of the SNHL with the radiation doses delivered to the inner ear.</p> <p>Methods</p> <p>A retrospective cohort study of 134 individual ears from 68 NPC patients, treated with conventional RT and IMRT in combination with chemotherapy from 2004-2008 was performed. Dosimetric data of the cochlea were analyzed. Significant SNHL was defined as > 15 dB increase in bone conduction threshold at 4 kHz and PTA (pure tone average of 0.5, 1, 2 kHz). Relative risk (RR) was used to determine the associated factors with the hearing threshold changes at 4 kHz and PTA.</p> <p>Results</p> <p>Median audiological follow up time was 14 months. The incidence of high frequency (4 kHz) SNHL was 44% for the whole group (48.75% in the conventional RT, 37% with IMRT). Internal auditory canal mean dose of > 50 Gy had shown a trend to increase the risk of high frequency SNHL (RR 2.02 with 95% CI 1.01-4.03, p = 0.047).</p> <p>Conclusion</p> <p>IMRT and radiation dose limitation to the inner ear appeared to decrease SNHL.</p

    Control of Vortex Pinning in YBCO Thin Films by Incorporating APCs Through Surface Modified Target Approach

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    The transport of electrical currents in superconductors with much higher efficiency and without any dissipation is considered as the “energy superhighway.” After the discovery of YBa2Cu3O7-δ (YBCO), a high temperature superconductor (HTS), the prospect of using superconducting materials in practical technological applications became very prominent. With much higher Tc (~ 92 K) than conventional low temperature superconductors (LTS), YBCO was considered very promising due to cheaper cooling requirements. The evolution of critical current density (Jc), however, took long time for the material to become useful in practical applications. This was achieved through continuous modification of the processing parameters, deposition of highly oriented thin films on single crystal and buffered metallic substrates and use of artificial pinning centers (APCs) for strong pinning of quantized magnetic vortices. Pulsed laser deposition (PLD) technique is one of the most common and highly efficient techniques for depositing highly oriented YBCO thin films on single crystal and buffered metallic substrates. Using PLD technique, APCs are incorporated into YBCO thin films by many methods which include premixed target method, alternating target method and surface modified target method. In this chapter, the use of surface modified target method to introduce different kinds of APCs into YBCO thin films is presented. These APCs are effective in improving the vortex pinning properties of YBCO thin films for different range of applied magnetic field and its orientation depending upon their geometry and density.Chapter
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