WorldWideScience

Sample records for base lesions positioned

  1. Candidate lesion-based criteria for defining a positive sacroiliac joint MRI in two cohorts of patients with axial spondyloarthritis

    DEFF Research Database (Denmark)

    Weber, Ulrich; Østergaard, Mikkel; Lambert, Robert G W

    2015-01-01

    OBJECTIVE: To determine candidate lesion-based criteria for a positive sacroiliac joint (SIJ) MRI based on bone marrow oedema (BMO) and/or erosion in non-radiographic axial spondyloarthritis (nr-axSpA); to compare the performance of lesion-based criteria with global evaluation by expert readers. ...... for classification of axial SpA, reflecting the contextual information provided by T1SE and STIR sequences....

  2. Intensity dependence of focused ultrasound lesion position

    Science.gov (United States)

    Meaney, Paul M.; Cahill, Mark D.; ter Haar, Gail R.

    1998-04-01

    Knowledge of the spatial distribution of intensity loss from an ultrasonic beam is critical to predicting lesion formation in focused ultrasound surgery. To date most models have used linear propagation models to predict the intensity profiles needed to compute the temporally varying temperature distributions. These can be used to compute thermal dose contours that can in turn be used to predict the extent of thermal damage. However, these simulations fail to adequately describe the abnormal lesion formation behavior observed for in vitro experiments in cases where the transducer drive levels are varied over a wide range. For these experiments, the extent of thermal damage has been observed to move significantly closer to the transducer with increasing transducer drive levels than would be predicted using linear propagation models. The simulations described herein, utilize the KZK (Khokhlov-Zabolotskaya-Kuznetsov) nonlinear propagation model with the parabolic approximation for highly focused ultrasound waves, to demonstrate that the positions of the peak intensity and the lesion do indeed move closer to the transducer. This illustrates that for accurate modeling of heating during FUS, nonlinear effects must be considered.

  3. Value of a dixon-based MR/PET attenuation correction sequence for the localization and evaluation of PET-positive lesions

    International Nuclear Information System (INIS)

    Eiber, Matthias; Holzapfel, Konstantin; Rummeny, Ernst J.; Martinez-Moeller, Axel; Souvatzoglou, Michael; Ziegler, Sibylle; Schwaiger, Markus; Nekolla, Stephan G.; Beer, Ambros J.; Pickhard, Anja; Loeffelbein, Dennys; Santi, Ivan

    2011-01-01

    In this study, the potential contribution of Dixon-based MR imaging with a rapid low-resolution breath-hold sequence, which is a technique used for MR-based attenuation correction (AC) for MR/positron emission tomography (PET), was evaluated for anatomical correlation of PET-positive lesions on a 3T clinical scanner compared to low-dose CT. This technique is also used in a recently installed fully integrated whole-body MR/PET system. Thirty-five patients routinely scheduled for oncological staging underwent 18 F-fluorodeoxyglucose (FDG) PET/CT and a 2-point Dixon 3-D volumetric interpolated breath-hold examination (VIBE) T1-weighted MR sequence on the same day. Two PET data sets reconstructed using attenuation maps from low-dose CT (PET AC C T ) or simulated MR-based segmentation (PET AC M R ) were evaluated for focal PET-positive lesions. The certainty for the correlation with anatomical structures was judged in the low-dose CT and Dixon-based MRI on a 4-point scale (0-3). In addition, the standardized uptake values (SUVs) for PET AC C T and PET AC M R were compared. Statistically, no significant difference could be found concerning anatomical localization for all 81 PET-positive lesions in low-dose CT compared to Dixon-based MR (mean 2.51 ± 0.85 and 2.37 ± 0.87, respectively; p = 0.1909). CT tended to be superior for small lymph nodes, bone metastases and pulmonary nodules, while Dixon-based MR proved advantageous for soft tissue pathologies like head/neck tumours and liver metastases. For the PET AC C T - and PET AC M R -based SUVs (mean 6.36 ± 4.47 and 6.31 ± 4.52, respectively) a nearly complete concordance with a highly significant correlation was found (r = 0.9975, p < 0.0001). Dixon-based MR imaging for MR AC allows for anatomical allocation of PET-positive lesions similar to low-dose CT in conventional PET/CT. Thus, this approach appears to be useful for future MR/PET for body regions not fully covered by diagnostic MRI due to potential time

  4. Position tracking of moving liver lesion based on real-time registration between 2D ultrasound and 3D preoperative images

    International Nuclear Information System (INIS)

    Weon, Chijun; Hyun Nam, Woo; Lee, Duhgoon; Ra, Jong Beom; Lee, Jae Young

    2015-01-01

    Purpose: Registration between 2D ultrasound (US) and 3D preoperative magnetic resonance (MR) (or computed tomography, CT) images has been studied recently for US-guided intervention. However, the existing techniques have some limits, either in the registration speed or the performance. The purpose of this work is to develop a real-time and fully automatic registration system between two intermodal images of the liver, and subsequently an indirect lesion positioning/tracking algorithm based on the registration result, for image-guided interventions. Methods: The proposed position tracking system consists of three stages. In the preoperative stage, the authors acquire several 3D preoperative MR (or CT) images at different respiratory phases. Based on the transformations obtained from nonrigid registration of the acquired 3D images, they then generate a 4D preoperative image along the respiratory phase. In the intraoperative preparatory stage, they properly attach a 3D US transducer to the patient’s body and fix its pose using a holding mechanism. They then acquire a couple of respiratory-controlled 3D US images. Via the rigid registration of these US images to the 3D preoperative images in the 4D image, the pose information of the fixed-pose 3D US transducer is determined with respect to the preoperative image coordinates. As feature(s) to use for the rigid registration, they may choose either internal liver vessels or the inferior vena cava. Since the latter is especially useful in patients with a diffuse liver disease, the authors newly propose using it. In the intraoperative real-time stage, they acquire 2D US images in real-time from the fixed-pose transducer. For each US image, they select candidates for its corresponding 2D preoperative slice from the 4D preoperative MR (or CT) image, based on the predetermined pose information of the transducer. The correct corresponding image is then found among those candidates via real-time 2D registration based on a

  5. An ultrasound-based comparative study on carotid plaques in HIV-positive patients vs. atherosclerotic and arteritis patients: atherosclerotic or inflammatory lesions?

    Science.gov (United States)

    Maggi, Paolo; Perilli, Francesco; Lillo, Antonio; Carito, Valentina; Epifani, Giuseppe; Bellacosa, Chiara; Pastore, Giuseppe; Regina, Guido

    2007-02-01

    We have previously described two cases of HIV-1-positive patients undergoing surgery for stenosis of the internal carotid arteries. Histology revealed an extensive inflammatory infiltration of the vascular wall and no evidence of atheromasic plaque. This unexpected pattern of carotid damage prompted us to perform a more accurate investigation of the characteristics of carotid plaques in a group of HIV-positive patients. The results were compared with those obtained from young patients affected by atherosclerosis of the epi-aortic vessels and patients with arteritis. The patients underwent ultrasonography of the epi-aortic vessels using one of the latest generation power color-Doppler with 7.5 MHz probes. The study population included 61 HIV-positive patients and 47 HIV-negative patients (37 atherosclerotic and 10 with arteritis). Compared with HIV-negative atherosclerotic patients, there were significantly higher proportions of HIV-positive patients with iso-hypoechogenic lesions (81.8 vs. 29%) that were homogeneous both in their parietal and endoluminal portions (96.7 vs. 21.6% and 88.5 vs. 54.0%, respectively), with a smooth or slightly irregular surface (99.0 vs. 56.7%) (P=0.001 for all differences). No statistically significant differences were seen between HIV-positive and arteritis patients. Our study evidenced that the ultrasonographic structure of the epi-aortic lesions in HIV-positive patients substantially differ from those of the plaques in atherosclerotic patients, although they share similar characteristics with patients affected by arteritis. Further investigations are warranted to better define the structure and the mechanism of onset of these lesions.

  6. Stereotactic biopsy of cerebellar lesions: straight versus oblique frame positioning.

    Science.gov (United States)

    Quick-Weller, Johanna; Brawanski, Nina; Dinc, Nazife; Behmanesh, Bedjahn; Kammerer, Sara; Dubinski, Daniel; Seifert, Volker; Marquardt, Gerhard; Weise, Lutz

    2017-10-26

    Biospies of brain lesions with unknown entity are an everyday procedure among many neurosurgical departments. Biopsies can be performed frame-guided or frameless. However, cerebellar lesions are a special entity with a more complex approach. All biopsies in this study were performed stereotactically frame guided. Therefore, only biopsies of cerebellar lesions were included in this study. We compared whether the frame was attached straight versus oblique and we focused on diagnostic yield and complication rate. We evaluated 20 patients who underwent the procedure between 2009 and 2017. Median age was 56.5 years. 12 (60%) Patients showed a left sided lesion, 6 (30%) showed a lesion in the right cerebellum and 2 (10%) patients showed a midline lesion. The stereotactic frame was mounted oblique in 12 (60%) patients and straight in 8 (40%) patients. Postoperative CT scan showed small, clinically silent blood collection in two (10%) of the patients, one (5%) patient showed haemorrhage, which caused a hydrocephalus. He received an external ventricular drain. In both patients with small haemorrhage the frame was positioned straight, while in the patient who showed a larger haemorrhage the frame was mounted oblique. In all patients a final histopathological diagnosis was established. Cerebellar lesions of unknown entity can be accessed transcerebellar either with the stereotactic frame mounted straight or oblique. Also for cerebellar lesions the procedure shows a high diagnostic yield with a low rate of severe complications, which need further treatment.

  7. Disseminated paracoccidioidomycosis diagnosis based on oral lesions

    Directory of Open Access Journals (Sweden)

    Liana Preto Webber

    2014-01-01

    Full Text Available Paracoccidioidomycosis (PCM is a deep mycosis with primary lung manifestations that may present cutaneous and oral lesions. Oral lesions mimic other infectious diseases or even squamous cell carcinoma, clinically and microscopically. Sometimes, the dentist is the first to detect the disease, because lung lesions are asymptomatic, or even misdiagnosed. An unusual case of PCM with 5 months of evolution presenting pulmonary, oral, and cutaneous lesions that was diagnosed by the dentist based on oral lesions is presented and discussed.

  8. Management of oral lesions in HIV-positive patients.

    Science.gov (United States)

    Baccaglini, Lorena; Atkinson, Jane C; Patton, Lauren L; Glick, Michael; Ficarra, Giuseppe; Peterson, Douglas E

    2007-03-01

    HIV/AIDS is currently the leading cause of death in Africa and the fourth leading cause of death worldwide. This systematic review of the literature was conducted to evaluate the evidence for treatment of the most common oral lesions associated with HIV: oral candidiasis with or without oropharyngeal involvement (OPC), oral hairy leukoplakia (OHL), recurrent aphthous-like ulcerations (RAU), oral Kaposi's sarcoma (OKS), orolabial herpes simplex infection (HSV), oral herpes zoster infection (VZV), intraoral or perioral warts (HPV), and HIV-associated periodontal diseases. Treatment of HIV-associated salivary gland disease is addressed in a different section of this World Workshop. We found the largest body of evidence for treatment of OPC in HIV patients. Future trials will be needed to test drugs currently in development for treatment of Candida strains that are resistant to existing therapies. There were no double blind, placebo-controlled randomized clinical trials (RCT) for topical treatment of OHL, and only one RCT for systemic treatment of the lesion with desciclovir. Systemic thalidomide was the only drug tested in RCT for treatment or prevention of RAU. Only 1 double-blind RCT comparing vinblastine and sodium tetradecyl sulfate was identified for localized treatment of OKS. Three drugs (famciclovir, acyclovir, and valaciclovir) were shown to be effective in randomized, double-blind trials for treatment or suppression of mucocutaneous HSV lesions in HIV patients. In all 3 trials, the effects of these medications on orolabial HSV lesions were not reported separately. There were no double-blind, placebo-controlled RCT testing topical treatments for orolabial HSV lesions in HIV patients. No trials testing treatments of oral VZV were identified. There were no double-blind, placebo-controlled RCT for treatment of HIV-associated intraoral or perioral warts or periodontal diseases. In conclusion, there is a need for well-designed RCTs to assess the safety and

  9. INTRACRANIAL MASS LESIONS IN HIV-POSITIVE PATIENTS ...

    African Journals Online (AJOL)

    'encephalitis of obscure origin', brain abscess and tuberculoma / mycobacterial ... Studies of IML in HN-positive patients emanate primarily from the ... Fig. 3. Mass on this CT scan found to be due to toxoplasmosis. Table H. Histological findings in the operated cases. Total biopsied/operated. 38'. Diagnosis. 0. Toxoplasmosis.

  10. The value of high-resolution anoscopy in the diagnosis of anal cancer precursor lesions in hiv-positive patients

    Directory of Open Access Journals (Sweden)

    Felicidad Gimenez

    2011-06-01

    Full Text Available CONTEXT: Anal cancer, although a still rare disease, is being observed in ascending rates among some population segments known to be at risk for the development of the disease. Human papillomavirus (HPV infection, immunodepression and anal intercourse are some factors associated with the development of the malignancy. Its similarities to cervical cancer have led to many studies aiming to establish guidelines for detecting and treating precursor lesions of anal cancer, with the goal of prevention. High-resolution anoscopy is routinely used for the diagnosis of anal cancer precursor lesions in many centers but the medical literature is still deficient concerning the role of this diagnostic modality. OBJECTIVES: To evaluate diagnostic validation and precision measures of high-resolution anoscopy in comparison to histopathological results of anal biopsies performed in HIV-positive patients treated at the Tropical Medicine Foundation of Amazonas, AM, Brazil. To observe any possible association between some risk factors for the development of anal cancer and the presence of anal squamous intraepithelial lesions. METHODS: A hundred and twenty-eight HIV-positive patients were submitted to anal canal cytological sampling for the detection of HPV infection by a PCR based method. High-resolution anoscopy was then performed after topical application of acetic acid 3% in the anal canal for 2 minutes. Eventual acetowhite lesions that were detected were recorded in respect to location, and classified by their tinctorial pattern, distribution aspect, relief, surface and vascular pattern. Biopsies of acetowhite lesions were performed under local anesthesia and the specimens sent to histopathological analysis. The patients were interviewed for the presence of anal cancer risk factors. RESULTS: The prevalences of anal HPV infection and of anal squamous intraepithelial lesions in the studied population were, respectively, 79% and 39.1%. High-resolution anoscopy

  11. Impact of positive and negative lesion site remodeling on clinical outcomes: insights from PROSPECT.

    Science.gov (United States)

    Inaba, Shinji; Mintz, Gary S; Farhat, Naim Z; Fajadet, Jean; Dudek, Dariusz; Marzocchi, Antonio; Templin, Barry; Weisz, Giora; Xu, Ke; de Bruyne, Bernard; Serruys, Patrick W; Stone, Gregg W; Maehara, Akiko

    2014-01-01

    This study investigated coronary artery remodeling patterns associated with clinical outcomes. In the prospective, multicenter PROSPECT (Providing Regional Observations to Study Predictors of Events in the Coronary Tree: An Imaging Study in Patients With Unstable Atherosclerotic Lesions) study, reported predictors of nonculprit lesion (NCL) major adverse cardiac events (MACE) were an intravascular ultrasound (IVUS) minimal lumen area (MLA) ≤4 mm(2), a plaque burden ≥70%, and a IVUS-virtual histology (VH) thin-cap fibroatheroma (TCFA), but not lesion site remodeling. Overall, 697 consecutive patients with an acute coronary syndrome were enrolled and underwent 3-vessel gray-scale and IVUS-VH; 3,223 NCLs were identified by IVUS. The remodeling index (RI) was calculated as the external elastic membrane area at the MLA site divided by the average of the proximal and distal reference external elastic membrane areas. First, one third of the patients were randomly selected to determine RI cutoffs related to NCL MACE (development cohort). Receiver-operating characteristic analysis showed that there were 2 separate cut points that predicted NCL MACE: RI = 0.8789 and RI = 1.0046 (area under the curve = 0.663). These cut points were used to define negative remodeling as an RI 1.00. Second, we used the remaining two-thirds of patients to validate these cut points with respect to lesion morphology and clinical outcomes (validation cohort). Kaplan-Meier curve analysis in the validation cohort showed that NCL MACE occurred more frequent (and equally) in negative and positive remodeling lesions compared with intermediate remodeling lesions. In this cohort, negative remodeling lesions had the smallest MLA, positive remodeling lesions had the largest plaque burden, and VH TCFA, especially VH TCFA with multiple necrotic cores, was most common in negatively remodeling lesions. The present study showed the novel concept that positive and negative lesion site remodeling was

  12. Discrimination and anatomical mapping of PET-positive lesions: comparison of CT attenuation-corrected PET images with coregistered MR and CT images in the abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, Felix P.; Crook, David W.; Mader, Caecilia E.; Appenzeller, Philippe; Schulthess, G.K. von; Schmid, Daniel T. [University Hospital Zurich, Department of Medical Radiology, Zurich (Switzerland)

    2013-01-15

    PET/MR has the potential to become a powerful tool in clinical oncological imaging. The purpose of this prospective study was to evaluate the performance of a single T1-weighted (T1w) fat-suppressed unenhanced MR pulse sequence of the abdomen in comparison with unenhanced low-dose CT images to characterize PET-positive lesions. A total of 100 oncological patients underwent sequential whole-body {sup 18}F-FDG PET with CT-based attenuation correction (AC), 40 mAs low-dose CT and two-point Dixon-based T1w 3D MRI of the abdomen in a trimodality PET/CT-MR system. PET-positive lesions were assessed by CT and MRI with regard to their anatomical location, conspicuity and additional relevant information for characterization. From among 66 patients with at least one PET-positive lesion, 147 lesions were evaluated. No significant difference between MRI and CT was found regarding anatomical lesion localization. The MR pulse sequence used performed significantly better than CT regarding conspicuity of liver lesions (p < 0.001, Wilcoxon signed ranks test), whereas no difference was noted for extrahepatic lesions. For overall lesion characterization, MRI was considered superior to CT in 40 % of lesions, equal to CT in 49 %, and inferior to CT in 11 %. Fast Dixon-based T1w MRI outperformed low-dose CT in terms of conspicuity and characterization of PET-positive liver lesions and performed similarly in extrahepatic tumour manifestations. Hence, under the assumption that the technical issue of MR AC for whole-body PET examinations is solved, in abdominal PET/MR imaging the replacement of low-dose CT by a single Dixon-based MR pulse sequence for anatomical lesion correlation appears to be valid and robust. (orig.)

  13. Discrimination and anatomical mapping of PET-positive lesions: comparison of CT attenuation-corrected PET images with coregistered MR and CT images in the abdomen

    International Nuclear Information System (INIS)

    Kuhn, Felix P.; Crook, David W.; Mader, Caecilia E.; Appenzeller, Philippe; Schulthess, G.K. von; Schmid, Daniel T.

    2013-01-01

    PET/MR has the potential to become a powerful tool in clinical oncological imaging. The purpose of this prospective study was to evaluate the performance of a single T1-weighted (T1w) fat-suppressed unenhanced MR pulse sequence of the abdomen in comparison with unenhanced low-dose CT images to characterize PET-positive lesions. A total of 100 oncological patients underwent sequential whole-body 18 F-FDG PET with CT-based attenuation correction (AC), 40 mAs low-dose CT and two-point Dixon-based T1w 3D MRI of the abdomen in a trimodality PET/CT-MR system. PET-positive lesions were assessed by CT and MRI with regard to their anatomical location, conspicuity and additional relevant information for characterization. From among 66 patients with at least one PET-positive lesion, 147 lesions were evaluated. No significant difference between MRI and CT was found regarding anatomical lesion localization. The MR pulse sequence used performed significantly better than CT regarding conspicuity of liver lesions (p < 0.001, Wilcoxon signed ranks test), whereas no difference was noted for extrahepatic lesions. For overall lesion characterization, MRI was considered superior to CT in 40 % of lesions, equal to CT in 49 %, and inferior to CT in 11 %. Fast Dixon-based T1w MRI outperformed low-dose CT in terms of conspicuity and characterization of PET-positive liver lesions and performed similarly in extrahepatic tumour manifestations. Hence, under the assumption that the technical issue of MR AC for whole-body PET examinations is solved, in abdominal PET/MR imaging the replacement of low-dose CT by a single Dixon-based MR pulse sequence for anatomical lesion correlation appears to be valid and robust. (orig.)

  14. Intracranial mass lesions in HIV-positive patients – the Kwazulu ...

    African Journals Online (AJOL)

    Background. Neurological disease heralds the development of AIDS in 10 - 20% of HIV-seropositive individuals. In over half of these cases the presentation will be that of an intracranial mass lesion (IML). In developed countries toxoplasmosis is the most frequent cause of IML in a positive patient, followed by primary central ...

  15. An ensemble deep learning based approach for red lesion detection in fundus images.

    Science.gov (United States)

    Orlando, José Ignacio; Prokofyeva, Elena; Del Fresno, Mariana; Blaschko, Matthew B

    2018-01-01

    Diabetic retinopathy (DR) is one of the leading causes of preventable blindness in the world. Its earliest sign are red lesions, a general term that groups both microaneurysms (MAs) and hemorrhages (HEs). In daily clinical practice, these lesions are manually detected by physicians using fundus photographs. However, this task is tedious and time consuming, and requires an intensive effort due to the small size of the lesions and their lack of contrast. Computer-assisted diagnosis of DR based on red lesion detection is being actively explored due to its improvement effects both in clinicians consistency and accuracy. Moreover, it provides comprehensive feedback that is easy to assess by the physicians. Several methods for detecting red lesions have been proposed in the literature, most of them based on characterizing lesion candidates using hand crafted features, and classifying them into true or false positive detections. Deep learning based approaches, by contrast, are scarce in this domain due to the high expense of annotating the lesions manually. In this paper we propose a novel method for red lesion detection based on combining both deep learned and domain knowledge. Features learned by a convolutional neural network (CNN) are augmented by incorporating hand crafted features. Such ensemble vector of descriptors is used afterwards to identify true lesion candidates using a Random Forest classifier. We empirically observed that combining both sources of information significantly improve results with respect to using each approach separately. Furthermore, our method reported the highest performance on a per-lesion basis on DIARETDB1 and e-ophtha, and for screening and need for referral on MESSIDOR compared to a second human expert. Results highlight the fact that integrating manually engineered approaches with deep learned features is relevant to improve results when the networks are trained from lesion-level annotated data. An open source implementation of our

  16. Health Physics Positions Data Base

    International Nuclear Information System (INIS)

    Kerr, G.D.; Borges, T.; Stafford, R.S.; Lu, P.Y.; Carter, D.

    1992-05-01

    The Health Physics Positions (HPPOS) Data Base of the Nuclear Regulatory Commission (NRC) is a collection of summaries of NRC staff positions on a wide range of topics in radiation protection (health physics). The bases for the data base are 247 original documents in the form of letters, memoranda, and excerpts from technical reports. The HPPOS Data Base was developed by the NRC Headquarters and Regional Offices to help ensure uniformity in inspections, enforcement, and licensing actions

  17. Voxel-based lesion-symptom mapping of stroke lesions underlying somatosensory deficits.

    Science.gov (United States)

    Meyer, Sarah; Kessner, Simon S; Cheng, Bastian; Bönstrup, Marlene; Schulz, Robert; Hummel, Friedhelm C; De Bruyn, Nele; Peeters, Andre; Van Pesch, Vincent; Duprez, Thierry; Sunaert, Stefan; Schrooten, Maarten; Feys, Hilde; Gerloff, Christian; Thomalla, Götz; Thijs, Vincent; Verheyden, Geert

    2016-01-01

    The aim of this study was to investigate the relationship between stroke lesion location and the resulting somatosensory deficit. We studied exteroceptive and proprioceptive somatosensory symptoms and stroke lesions in 38 patients with first-ever acute stroke. The Erasmus modified Nottingham Sensory Assessment was used to clinically evaluate somatosensory functioning in the arm and hand within the first week after stroke onset. Additionally, more objective measures such as the perceptual threshold of touch and somatosensory evoked potentials were recorded. Non-parametric voxel-based lesion-symptom mapping was performed to investigate lesion contribution to different somatosensory deficits in the upper limb. Additionally, structural connectivity of brain areas that demonstrated the strongest association with somatosensory symptoms was determined, using probabilistic fiber tracking based on diffusion tensor imaging data from a healthy age-matched sample. Voxels with a significant association to somatosensory deficits were clustered in two core brain regions: the central parietal white matter, also referred to as the sensory component of the superior thalamic radiation, and the parietal operculum close to the insular cortex, representing the secondary somatosensory cortex. Our objective recordings confirmed findings from clinical assessments. Probabilistic tracking connected the first region to thalamus, internal capsule, brain stem, postcentral gyrus, cerebellum, and frontal pathways, while the second region demonstrated structural connections to thalamus, insular and primary somatosensory cortex. This study reveals that stroke lesions in the sensory fibers of the superior thalamocortical radiation and the parietal operculum are significantly associated with multiple exteroceptive and proprioceptive deficits in the arm and hand.

  18. Risk of persistent high-grade squamous intraepithelial lesion after electrosurgical excisional treatment with positive margins: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Caroline Alves de Oliveira

    Full Text Available CONTEXT AND OBJECTIVE: Even if precursor lesions of cervical cancer are properly treated, there is a risk of persistence or recurrence. The aim here was to quantify the risks of persistence of high-grade intraepithelial squamous lesions, one and two years after cervical electrosurgical excisional treatment with positive margins. DESIGN AND SETTING: Systematic review of the literature and meta-analysis at Instituto Fernandes Figueira. METHODS: This meta-analysis was on studies published between January 1989 and July 2009 that were identified in Medline, Scopus, Embase, Cochrane, SciELO, Lilacs, Adolec, Medcarib, Paho, Wholis, Popline, ISI Web of Science and Sigle. Articles were selected if they were cohort studies on electrosurgical excisional treatment of high-grade squamous intraepithelial lesions with a minimum follow-up of one year, a histopathological outcome of persistence of these lesions and a small risk of bias. RESULTS: The search identified 7,066 articles and another 21 in the reference lists of these papers. After applying the selection and exclusion criteria, only four articles were found to have extractable data. The risk of persistence of high-grade intraepithelial lesions after one year was 11.36 times greater (95% confidence interval, CI: 5.529-23.379, P < 0.0001 in patients with positive margins and after two years, was four times greater (95% CI: 0.996-16.164, although without statistical significance. CONCLUSION: This meta-analysis confirms the importance of positive margins as an indicator of incomplete treatment after the first year of follow-up and highlights the need for appropriately chosen electrosurgical techniques based on disease location and extent, with close surveillance of these patients.

  19. 'Do not touch' lesions of the skull base

    International Nuclear Information System (INIS)

    Dobre, Mircea C.; Fischbein, Nancy

    2014-01-01

    Imaging of the skull base presents many challenges due to its anatomical complexity, numerous normal variants and lack of familiarity to many radiologists. As the skull base is a region which is not amenable to physical examination and as lesions of the skull base are generally difficult to biopsy and even more difficult to operate on, the radiologist plays a major role in directing patient management via accurate image interpretation. Knowledge of the skull base should not be limited to neuroradiologists and head and neck radiologists, however, as the central skull base is routinely included in the field of view when imaging the brain, cervical spine, or head and neck with computed tomography or magnetic resonance imaging, and hence, its nuances should be familiar to general radiologists as well. We herein review the imaging findings of a subcategory of lesions of the central skull base, the 'do not touch' lesions.

  20. Voxel-based lesion-symptom mapping of stroke lesions underlying somatosensory deficits

    Directory of Open Access Journals (Sweden)

    Sarah Meyer

    2016-01-01

    Full Text Available The aim of this study was to investigate the relationship between stroke lesion location and the resulting somatosensory deficit. We studied exteroceptive and proprioceptive somatosensory symptoms and stroke lesions in 38 patients with first-ever acute stroke. The Erasmus modified Nottingham Sensory Assessment was used to clinically evaluate somatosensory functioning in the arm and hand within the first week after stroke onset. Additionally, more objective measures such as the perceptual threshold of touch and somatosensory evoked potentials were recorded. Non-parametric voxel-based lesion-symptom mapping was performed to investigate lesion contribution to different somatosensory deficits in the upper limb. Additionally, structural connectivity of brain areas that demonstrated the strongest association with somatosensory symptoms was determined, using probabilistic fiber tracking based on diffusion tensor imaging data from a healthy age-matched sample. Voxels with a significant association to somatosensory deficits were clustered in two core brain regions: the central parietal white matter, also referred to as the sensory component of the superior thalamic radiation, and the parietal operculum close to the insular cortex, representing the secondary somatosensory cortex. Our objective recordings confirmed findings from clinical assessments. Probabilistic tracking connected the first region to thalamus, internal capsule, brain stem, postcentral gyrus, cerebellum, and frontal pathways, while the second region demonstrated structural connections to thalamus, insular and primary somatosensory cortex. This study reveals that stroke lesions in the sensory fibers of the superior thalamocortical radiation and the parietal operculum are significantly associated with multiple exteroceptive and proprioceptive deficits in the arm and hand.

  1. Papulonodular Secondary Syphilis Presenting as Multiple Distinct Cutaneous Lesions in an HIV-Positive Transgender Woman

    Directory of Open Access Journals (Sweden)

    Kristina Navrazhina

    2017-03-01

    Full Text Available We present the first reported case of papulonodular secondary syphilis in an HIV-positive transgender female. Syphilis is classified into primary, secondary, latent, and tertiary stages, with secondary syphilis having notably diverse cutaneous manifestations. Our patient presented with diverse lesions throughout her body, all pathologically consistent with papulonodular secondary syphilis. Proper identification of the multiple presentations of syphilis is crucial to early diagnosis and treatment. This report seeks to broaden the scope of dermatological manifestations that arise secondary to papulonodular syphilis in HIV-positive patients.

  2. Osteochondritis Dissecans Lesions in Family Members: Does a Positive Family History Impact Phenotypic Potency?

    Science.gov (United States)

    Gornitzky, Alex L; Mistovich, R Justin; Atuahuene, Brittany; Storey, Eileen P; Ganley, Theodore J

    2017-06-01

    Although repetitive microtrauma and athletic overuse patterns are most commonly associated with osteochondritis dissecans (OCD), recent studies have identified a potential genetic predisposition for OCD. Several case series have documented family pedigrees that support autosomal-dominant inheritance, but the families in these studies were all selected as a result of unique histories that may not accurately represent OCD inheritance patterns at large. Because there has been little investigation beyond these case reports, we aimed to describe a broader, more representative pattern of OCD inheritance applicable to all affected patients. (1) What proportion of patients treated for OCD of the knee have one or more immediate and/or extended family members with a history of OCD lesions? (2) Do patients with more phenotypically potent lesions, which we defined as patients with bilateral OCD lesions or patients who have undergone multiple procedures for OCD, have a higher frequency of affected relatives than those with less potent lesions? This retrospective study queried patient databases, diagnosis codes (International Classification of Diseases, 9th Revision), and surgical logs at a regional, tertiary care children's hospital to identify all patients treated over a 10-year period (March 2004-March 2014) by the senior author for OCD of the knee. All patients aged 0-18 years at the time of diagnosis were included. At our institution, patients with intact lesions are treated with a trial of conservative therapy; conversely, patients with a break in the articular cartilage and/or loose fragments of bone/cartilage are treated surgically. There were no OCD-specific contraindications to surgery. This search identified 543 patients. After patient identification, a questionnaire was designed that asked for the number, age, and gender of all immediate family members and the history of OCD lesions in any family member (immediate or extended). For all positive family members

  3. Medical Imaging Lesion Detection Based on Unified Gravitational Fuzzy Clustering

    Directory of Open Access Journals (Sweden)

    Jean Marie Vianney Kinani

    2017-01-01

    Full Text Available We develop a swift, robust, and practical tool for detecting brain lesions with minimal user intervention to assist clinicians and researchers in the diagnosis process, radiosurgery planning, and assessment of the patient’s response to the therapy. We propose a unified gravitational fuzzy clustering-based segmentation algorithm, which integrates the Newtonian concept of gravity into fuzzy clustering. We first perform fuzzy rule-based image enhancement on our database which is comprised of T1/T2 weighted magnetic resonance (MR and fluid-attenuated inversion recovery (FLAIR images to facilitate a smoother segmentation. The scalar output obtained is fed into a gravitational fuzzy clustering algorithm, which separates healthy structures from the unhealthy. Finally, the lesion contour is automatically outlined through the initialization-free level set evolution method. An advantage of this lesion detection algorithm is its precision and its simultaneous use of features computed from the intensity properties of the MR scan in a cascading pattern, which makes the computation fast, robust, and self-contained. Furthermore, we validate our algorithm with large-scale experiments using clinical and synthetic brain lesion datasets. As a result, an 84%–93% overlap performance is obtained, with an emphasis on robustness with respect to different and heterogeneous types of lesion and a swift computation time.

  4. Analysis of false positive and false negative cytological diagnosis of breast lesions

    International Nuclear Information System (INIS)

    Jamal, Awtif A.; Mansoor, I.

    2001-01-01

    To study the reasons for interpretive errors in false negative and false positive diagnosis of breast carcinoma on fine needle aspiration cytology material. We reviewed only those cases in which cytohistological discrepancies were found, where the cytologic material was abnormal and to some extent misinterpreted or both. There was only one false negative case (false negative fraction 0.32%) proved histologically as ductal carcinoma and four false positive cases (false positive fraction 1.2%); 2 fibroadenoma; 1 fibrocystic disease; and 1 stromal fibrosis. Smears of the two false positive fibroadenoma cases showed very high cellularity, overcrowded clusters and frequent stripped nuclei. The fibrocystic case showed tight clusters of apocrine cells and sheets of loosely aggregated macrophages that were over interpreted. Smears of the false negative ductal carcinoma was hypocellular overall, and the cells showed minimal nuclear pleomorphism. Overcrowded clusters and hypercellular smears should be carefully assessed for uniformity of cells and detailed nuclear and cytomorphological features. If the full-blown malignant cytomorphological changes are not visible, a diagnosis of suspicious or inconclusive should be made and frozen section recommended before surgery. Hypocellularity and relatively nuclear monomorphism are the reasons for failure to diagnose malignant breast lesions. Careful attention should be paid to extreme nuclear monomorphism and absence of naked bipolar cells. A cytologically atypical or suspicious diagnosis together with positive radiological and clinical findings should suggest a diagnosis of malignancy. (author)

  5. Human papillomavirus-32-associated focal epithelial hyperplasia accompanying HPV-16-positive papilloma-like lesions in oral mucosa.

    Science.gov (United States)

    Liu, Na; Wang, Jiayi; Lei, Lei; Li, Yanzhong; Zhou, Min; Dan, Hongxia; Zeng, Xin; Chen, Qianming

    2013-05-01

    Human papillomavirus infection can cause a variety of benign or malignant oral lesions, and the various genotypes can cause distinct types of lesions. To our best knowledge, there has been no report of 2 different human papillomavirus-related oral lesions in different oral sites in the same patient before. This paper reported a patient with 2 different oral lesions which were clinically and histologically in accord with focal epithelial hyperplasia and oral papilloma, respectively. Using DNA extracted from these 2 different lesions, tissue blocks were tested for presence of human papillomavirus followed by specific polymerase chain reaction testing for 6, 11, 13, 16, 18, and 32 subtypes in order to confirm the clinical diagnosis. Finally, human papillomavirus-32-positive focal epithelial hyperplasia accompanying human papillomavirus-16-positive oral papilloma-like lesions were detected in different sites of the oral mucosa. Nucleotide sequence sequencing further confirmed the results. So in our clinical work, if the simultaneous occurrences of different human papillomavirus associated lesions are suspected, the multiple biopsies from different lesions and detection of human papillomavirus genotype are needed to confirm the diagnosis.

  6. Usefulness and limits of ultrasound guided hook-wire positioning for localisation of soft tissue lesions prior to surgery

    International Nuclear Information System (INIS)

    Trenaghi, Alberto; Dal Bosco, Chiara; Talenti, Enrico; Rubaltelli, Enrico; Borsato, Simonetta; Rossi, Carlo Riccardo; Lumachi, Franco

    2005-01-01

    Purpose. The aim of our study was to assess the usefulness of positioning metal wires under ultrasound guidance for localising soft tissue lesions in the preoperative phase. Materials and methods. We studied superficial soft-tissue lesions in 12 patients, using hooked mammographic wires of different lengths. One patient had a multifocal growth of disease which required a double localisation procedure. Correct positioning of the wire was confirmed by ultrasonography. All patients underwent surgery within five hours of hook-wire positioning. Results. Correct wire position was confirmed at surgery in 12 out of 13 procedures. In one case the hook-wire reached the margin of the lesion. In all cases, the preoperative localisation procedure facilitated identification and resection of the masses. Conclusions. In our experience, the main indications for hook-wire positioning before surgery are: marking of small lesions, localisation of lesions in anatomic areas structurally subverted by previous surgery and consequently difficult to detect, guidance for surgical sectioning in order to safeguard the noble structures dose to the lesions [it

  7. Clinical evaluation of false-positive scintigraphic lesions of the left lobe in portal hypertension

    International Nuclear Information System (INIS)

    Takayasu, Kenichi; Moriyama, Noriyuki; Suzuki, Masao; Yamada, Tatsuya; Fukutake, Toshio.

    1982-01-01

    sup(99m)Tc-phytate liver scan and percutaneous transhepatic portography (PTP) were performed in 33 patients with portal hypertension due to various hepatic diseases. A defect or space occupying lesion in the left lobe on the scan in these patients was analysed with reference to portographic changes of the pars umbilicus of the left portal vein and the following results were obtained. 1) A false-positive defect on the scintigram was found in 6 (18.2%) of 33 patients, and portal vein pressure (PVP) was above 200 mmH 2 O in all 6 which constituted 21.4% of 28 with PVP above 200 mmH 2 O. 2) In five out of 6 patients with false-positive scan findings, the pars umbilicus was dilated to more than 25 x 15 mm in size, and it was huge and tortuous in 3 of them. 3) The mean PVP in the group with a false-positive scan tended to be higher than that in patients with no abnormalities on the scintigram. It was concluded that in reading of liver scintigrams in patients with portal hypertension, a dilated pars umbilicus and huge para-umbilical vein should be considered. (author)

  8. Benign thyroid and neck lesions mimicking malignancy with false positive findings on positron emission tomography-computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Ye Ri; Kim, Shin Young; Lee, Sang Mi [Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of); Lee, Deuk Young [Dept. of Surgery, Younsei Angelot Women' s Clinic, Cheonan (Korea, Republic of)

    2017-02-15

    The increasing use of positron emission tomography-computed tomography (PET/CT) has led to the frequent detection of incidental thyroid and neck lesions with increased 18F-deoxyglucose (FDG) uptake. Although lesions with increased FDG uptake are commonly assumed to be malignant, benign lesions may also exhibit increased uptake. The purpose of this pictorial essay is to demonstrate that benign thyroid and neck lesions can produce false-positive findings on PET/CT, and to identify various difficulties in interpretation. It is crucial to be aware that differentiating between benign and malignant lesions is difficult in a considerable proportion of cases, when relying only on PET/CT findings. Correlation of PET/CT findings with additional imaging modalities is essential to avoid misdiagnosis.

  9. Background based Gaussian mixture model lesion segmentation in PET

    Energy Technology Data Exchange (ETDEWEB)

    Soffientini, Chiara Dolores, E-mail: chiaradolores.soffientini@polimi.it; Baselli, Giuseppe [DEIB, Department of Electronics, Information, and Bioengineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, Milan 20133 (Italy); De Bernardi, Elisabetta [Department of Medicine and Surgery, Tecnomed Foundation, University of Milano—Bicocca, Monza 20900 (Italy); Zito, Felicia; Castellani, Massimo [Nuclear Medicine Department, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, via Francesco Sforza 35, Milan 20122 (Italy)

    2016-05-15

    Purpose: Quantitative {sup 18}F-fluorodeoxyglucose positron emission tomography is limited by the uncertainty in lesion delineation due to poor SNR, low resolution, and partial volume effects, subsequently impacting oncological assessment, treatment planning, and follow-up. The present work develops and validates a segmentation algorithm based on statistical clustering. The introduction of constraints based on background features and contiguity priors is expected to improve robustness vs clinical image characteristics such as lesion dimension, noise, and contrast level. Methods: An eight-class Gaussian mixture model (GMM) clustering algorithm was modified by constraining the mean and variance parameters of four background classes according to the previous analysis of a lesion-free background volume of interest (background modeling). Hence, expectation maximization operated only on the four classes dedicated to lesion detection. To favor the segmentation of connected objects, a further variant was introduced by inserting priors relevant to the classification of neighbors. The algorithm was applied to simulated datasets and acquired phantom data. Feasibility and robustness toward initialization were assessed on a clinical dataset manually contoured by two expert clinicians. Comparisons were performed with respect to a standard eight-class GMM algorithm and to four different state-of-the-art methods in terms of volume error (VE), Dice index, classification error (CE), and Hausdorff distance (HD). Results: The proposed GMM segmentation with background modeling outperformed standard GMM and all the other tested methods. Medians of accuracy indexes were VE <3%, Dice >0.88, CE <0.25, and HD <1.2 in simulations; VE <23%, Dice >0.74, CE <0.43, and HD <1.77 in phantom data. Robustness toward image statistic changes (±15%) was shown by the low index changes: <26% for VE, <17% for Dice, and <15% for CE. Finally, robustness toward the user-dependent volume initialization was

  10. Do positive or negative stressful events predict the development of new brain lesions in people with Multiple Sclerosis?

    Science.gov (United States)

    Burns, Michelle Nicole; Nawacki, Ewa; Kwasny, Mary J.; Pelletier, Daniel; Mohr, David C.

    2014-01-01

    Background Stressful life events have long been suspected to contribute to multiple sclerosis (MS) disease activity. The few studies examining the relationship between stressful events and neuroimaging markers have been small and inconsistent. This study examined whether different types of stressful events and perceived stress could predict development of brain lesions. Methods This was a secondary analysis of 121 patients with MS followed for 48 weeks during a randomized controlled trial comparing Stress Management Therapy for MS to a waitlist control. Patients underwent MRI’s every 8 weeks. Monthly, patients completed an interview measure assessing stressful life events, and self-report measures of perceived stress, anxiety, and depressive symptoms, which were used to predict the presence of gadolinium enhancing (Gd+) and T2 lesions on MRI’s 29–62 days later. Participants classified stressful events as positive or negative. Negative events were considered “major” if they involved physical threat or threat to the patient’s family structure, and “moderate” otherwise. Results Positive stressful events predicted decreased risk for subsequent Gd+ lesions in the control group (OR=.53 for each additional positive stressful event, 95% CI=.30–.91) and less risk for new or enlarging T2 lesions regardless of group assignment (OR=.74, 95% CI=.55–.99). Across groups, major negative stressful events predicted Gd+ lesions (OR=1.77, 95% CI=1.18–2.64) and new or enlarging T2 lesions (OR=1.57, 95% CI=1.11–2.23), while moderate negative stressful events, perceived stress, anxiety, and depressive symptoms did not. Conclusions Major negative stressful events predict increased risk for Gd+ and T2 lesions, while positive stressful events predict decreased risk. PMID:23680407

  11. Difficulty of MRI based identification of lesion age by acute infra-tentorial ischemic stroke.

    Directory of Open Access Journals (Sweden)

    Florian Grosse-Dresselhaus

    Full Text Available Systemic thrombolysis in acute ischemic stroke is restricted to the 4.5 h time window. Many patients are excluded from this treatment because symptom onset is unknown. Magnetic resonance imaging (MRI studies have shown that stroke patients presenting with acute supra-tentorial diffusion-weighted imaging (DWI lesions that do not have matching lesions on fluid attenuated inversion recovery (FLAIR are likely to be within a 4.5 hour time window. This study examines the DWI-FLAIR mismatch in infra-tentorial stroke.This was a retrospectively conducted substudy of the "1000+" study; a prospective, single-center observational study (http://clinicaltrials.gov; NCT00715533. Fifty-six patients with infra-tentorial stroke confirmed by MRI and known symptom onset who underwent the scan within 24 h after symptom onset were analysed. Two neurologists blinded to clinical information separately rated the DWI lesion visibility on FLAIR. Lesion volume, relative signal intensities of DWI and relative apparent diffusion coefficient values were determined.Regarding baseline characteristics our study population had a median age of 66 years, a median time from symptom onset to MRI of 616.5 minutes, a median NIHSS of 3 and a median DWI lesion volume of 0.26 ml. A negative FLAIR allocated patients to a time window under 4.5 h correctly with a sensitivity of 55% and a specificity of 61%, a positive predictive value of 44% and a negative predictive value of 71%. FLAIR positivity decreased with age (p = 0.018, and showed no significant correlation to lesion volume (p = 0.145.In our study the DWI-FLAIR-Mismatch does not help to reliably identify patients within 4.5 h of symptom onset in acute ischemic infra-tentorial stroke. Thus therapeutical decisions based on the DWI-FLAIR mismatch estimation of time from onset cannot be recommended in patients with infra-tentorial stroke.

  12. Positive immunostaining for feline infectious peritonitis (FIP) in a Sphinx cat with cutaneous lesions and bilateral panuveitis.

    Science.gov (United States)

    Bauer, Bianca S; Kerr, Moira E; Sandmeyer, Lynne S; Grahn, Bruce H

    2013-07-01

    Feline infectious peritonitis (FIP) is a common, fatal, systemic disease of cats. This case report describes the antemortem diagnosis of FIP in a 2-year-old spayed female Sphinx cat that presented with a bilateral panuveitis and multiple papular cutaneous lesions. Histopathologically, the skin lesions were characterized by perivascular infiltrates of macrophages, neutrophils, with fewer plasma cells, mast cells, and small lymphocytes in the mid- to deep dermis. Immunohistochemistry for intracellular feline coronavirus (FeCoV) antigen demonstrated positive staining in dermal macrophages providing an antemortem diagnosis of a moderate, nodular to diffuse, pyogranulomatous perivascular dermatitis due to FIP infection. Obtaining an antemortem diagnosis of FIP can be a challenge and cutaneous lesions are rare in the disease. Recognition and biopsy of any cutaneous lesions in cats with panuveitis and suspected FIP can help establish an antemortem diagnosis of the disease. © 2013 American College of Veterinary Ophthalmologists.

  13. Screening, prevalence, and risk factors for cervical lesions among HIV positive and HIV negative women in Swaziland

    Directory of Open Access Journals (Sweden)

    Pauline E. Jolly

    2017-02-01

    Full Text Available Abstract Background Cervical Cancer (CC is the number one cancer among women in sub-Saharan Africa. Although CC is preventable, most women in developing countries do not have access to screening. Methods This cross-sectional study was conducted to determine the prevalence and risk factors for cervical lesions using visual inspection with acetic acid (VIA among 112 HIV positive and 161 negative women aged 18–69 years. Results The presence of cervical lesions was greater among HIV positive (22.9% than HIV negative women (5.7%; p < 0.0001. In logistic models, the risk of cervical lesions among HIV positive women was 5.24 times higher when adjusted by age (OR 5.24, CI 2.31–11.88, and 4.06 times higher in a full model (OR 4.06, CI 1.61–10.25, than among HIV negative women. In the age-adjusted model women who had ≥2 lifetime sexual partners were 3 times more likely (OR 3.00, CI 1.02–8.85 to have cervical lesions compared to women with one lifetime partner and the odds of cervical lesions among women with a history of STIs were 2.16 greater (OR 2.16, CI 1.04–4.50 than among women with no previous STI. In the fully adjusted model women who had a previous cervical exam were 2.5 times more likely (OR 2.53, CI 1.06–6.05 to have cervical lesions than women who had not. Conclusions The high prevalence of HIV infection and the strong association between HIV and cervical lesions highlight the need for substantial scale-up of cervical screening to decrease the rate of CC in Swaziland.

  14. Clinical analysis of skin lesions in 796 Chinese HIV- positive patients.

    Science.gov (United States)

    Huang, Xiao-jie; Li, Hai-ying; Chen, De-xi; Wang, Xi-cheng; Li, Zai-chun; Wu, Ya-song; Zhang, Tong; Gao, Yan-qing; Wu, Hao

    2011-09-01

    Skin lesions are often associated with human immunodeficiency virus (HIV) infection, reflecting the immunocompromised status of the individual. We investigated the relationship between skin lesions and immune function in a retrospective study of 796 Chinese HIV patients with and without highly active antiretroviral therapy (HAART). Of the 651 patients who had not received HAART, we found that 531 (81.6%) had apparent skin lesions. The incidence of infectious skin diseases (fungi, viruses, bacteria, spirochetes and parasites) and non-infectious skin diseases (excluding skin cancer) was 68.8% and 34.9%, respectively. Mean CD4(+) T-cell counts and CD4(+)/CD8(+) ratios were lower in patients with skin lesions than in patients without lesions (178 ± 96/µl vs. 306 ± 189/µl (p Candidiasis (25.8%), eczema (19.2%), nodular prurigo (13.8%), dermatophyte infections (10.6%) and herpes zoster (9.4%) were most common in Chinese patients with HIV. Among the 145 patients who had started HAART, there was a significantly lower prevalence of skin diseases (29.0%), although drug eruptions (12.4%) were more commonly observed. These findings indicate that HAART often reduces the incidence of infectious and non-infectious skin lesions in patients with HIV, but can itself be the cause of drug eruptions.

  15. Evaluation of colonic lesions and pitfalls in CT colonography: A systematic approach based on morphology, attenuation and mobility

    International Nuclear Information System (INIS)

    Mang, Thomas; Gryspeerdt, Stefaan; Schima, Wolfgang; Lefere, Philippe

    2013-01-01

    Computed tomographic colonography is a reliable technique for the detection and classification of neoplastic and non-neoplastic lesions of the colon. It is based on a thin-section CT dataset of the cleansed and air-distended colon, acquired in prone and supine position. Two-dimensional and 3D projections are used in combination for image interpretation. The evaluation of CT colonography datasets is based on two steps, lesion perception to detect a polyp candidate and image interpretation to correctly characterize colonic filling defects. A thorough knowledge of the morphologic and attenuation characteristics of common colonic lesions and artifacts facilitates characterization of the findings. The purpose of this review article is to give an overview of the key CT colonographic imaging criteria to correctly characterize common colorectal lesions and to identify typical pitfalls and pseudolesions

  16. Respiratory Therapy for Acute Lung Lesion, by Using Biphasic Positive Pressure Ventilation

    Directory of Open Access Journals (Sweden)

    Yu. V. Marchenkov

    2005-01-01

    Full Text Available Objective. To comparatively study the efficiency of respiratory support in patients with acute lung lesion, by applying BIPAP, SIMV, and aIPPV.Subjects. Twenty-six patients with acute lung lesion whose pattern included acute respiratory distress syndrome (n=16, pneumonia (и=6, and pneumonitis (n=4 were examined. The severity of disease was 18 to 21 APACHE II scale score.Results. The use of BIPAP leads to a better adaptation of a patient to respiratory support, to a reduction in the number of used myorelaxants and sedatives, and to improvement of gas exchange in the lung and diminishes the negative impact of artificial ventilation on hemodynamics. As compared with other types of assisted ventilation, BIPAP accelerates transfer from total respiratory support to spontaneous breathing.

  17. Lung lesion doubling times: values and variability based on method of volume determination

    International Nuclear Information System (INIS)

    Eisenbud Quint, Leslie; Cheng, Joan; Schipper, Matthew; Chang, Andrew C.; Kalemkerian, Gregory

    2008-01-01

    Purpose: To determine doubling times (DTs) of lung lesions based on volumetric measurements from thin-section CT imaging. Methods: Previously untreated patients with ≥ two thin-section CT scans showing a focal lung lesion were identified. Lesion volumes were derived using direct volume measurements and volume calculations based on lesion area and diameter. Growth rates (GRs) were compared by tissue diagnosis and measurement technique. Results: 54 lesions were evaluated including 8 benign lesions, 10 metastases, 3 lymphomas, 15 adenocarcinomas, 11 squamous carcinomas, and 7 miscellaneous lung cancers. Using direct volume measurements, median DTs were 453, 111, 15, 181, 139 and 137 days, respectively. Lung cancer DTs ranged from 23-2239 days. There were no significant differences in GRs among the different lesion types. There was considerable variability among GRs using different volume determination methods. Conclusions: Lung cancer doubling times showed a substantial range, and different volume determination methods gave considerably different DTs

  18. Optical-Based Artificial Palpation Sensors for Lesion Characterization

    Directory of Open Access Journals (Sweden)

    Hee-Jun Park

    2013-08-01

    Full Text Available Palpation techniques are widely used in medical procedures to detect the presence of lumps or tumors in the soft breast tissues. Since these procedures are very subjective and depend on the skills of the physician, it is imperative to perform detailed a scientific study in order to develop more efficient medical sensors to measure and generate palpation parameters. In this research, we propose an optical-based, artificial palpation sensor for lesion characterization. This has been developed using a multilayer polydimethylsiloxane optical waveguide. Light was generated at the critical angle to reflect totally within the flexible and transparent waveguide. When a waveguide was compressed by an external force, its contact area would deform and cause the light to scatter. The scattered light was captured by a high-resolution camera and saved as an image format. To test the performance of the proposed system, we used a realistic tissue phantom with embedded hard inclusions. The experimental results show that the proposed sensor can detect inclusions and provide the relative value of size, depth, and Young’s modulus of an inclusion.

  19. Effect of lesion site on serial position during list learning: a study with the CVLT.

    Science.gov (United States)

    Albuquerque, Luisa; Loureiro, Clara; Martins, Isabel Pavao

    2008-07-01

    Successful learning of supraspan word lists such as the California Verbal Learning Test (CVLT) relies more on clustering strategies than rote learning, subserved by the frontal and temporal lobes. The authors studied the effect of word sequence in CVLT learning, in 15 patients with frontal (FLL) and 15 temporal (TLL) lesions, and 33 controls. Experimental measures were: number of clusters, number of first (FI), middle (MI) and last items (LI), in learning trials and in total immediate recall. FLL disclosed significantly lower FI along learning. Clusters were similar among groups. This difficulty is discussed according to the role of frontal lobes in learning and memory.

  20. Hippocampal lesions impair performance on a conditional delayed matching and non-matching to position task in the rat.

    Science.gov (United States)

    Sloan, Hazel L; Döbrössy, Màtè; Dunnett, Stephen B

    2006-08-10

    The hippocampus is thought to be involved in a range of cognitive processes, from the ability to acquire new memories, to the ability to learn about spatial relationships. Humans and monkeys with damage to the hippocampus are typically impaired on delayed matching to sample tasks, of which the operant delayed matching to position task (DMTP) is a rat analogue. The reported effects of hippocampal damage on DMTP vary, ranging from delay-dependent deficits to no deficit whatsoever. The present study investigates a novel memory task; the conditional delayed matching/non-matching to position task (CDM/NMTP) in the Skinner box. CDM/NMTP uses the presence of specific stimulus cues to signify whether a particular trial is matching or non-matching in nature. Thus, it incorporates both the task contingencies within one session, and supplements the requirement for remembering the side of the lever in the sample phase with attending to the stimulus and remembering the conditional discrimination for the rule. Rats were trained preoperatively and the effects of bilateral excitotoxic lesions of the hippocampus were examined on postoperative retention of the task. Rats with lesions of the hippocampus incurred a significant impairment on the task that was manifest at all delays intervals. Despite a bias towards matching during training, trials of either type were performed with equivalent accuracy and neither rule was affected differentially by the lesion. This task may prove useful in determining the cognitive roles of a range of brain areas.

  1. Cryptococcal neuroradiological lesions correlate with severity during cryptococcal meningoencephalitis in HIV-positive patients in the HAART era.

    Directory of Open Access Journals (Sweden)

    Caroline Charlier

    Full Text Available Cryptococcal meningoencephalitis has an overall global mortality rate of 20% in AIDS patients despite antifungals. There is a need for additional means of precise assessment of disease severity. We thus studied the radiological brain images available from 62 HIV-positive patients with cryptococcocal meningoencephalitis to analyse the brain lesions associated with cryptococcosis in relationship with disease severity, and the respective diagnostic contribution of magnetic resonance (MR versus computed tomography (CT. In this retrospective multicenter analysis, two neuroradiologists blindly reviewed the brain imaging. Prospectively acquired clinical and mycological data were available at baseline and during follow-up. Baseline images were abnormal on 92% of the MR scans contrasting with 53% of the CT scans. MR/CT cryptococcosis-related lesions included mass(es (21%/9%, dilated perivascular spaces (46%/5% and pseudocysts (8%/4%. The presence compared to absence of cryptococcosis-related lesions was significantly associated with high serum (78% vs. 42%, p = 0.008 and CSF (81% vs. 50%, p = 0.024 antigen titers, independently of neurological abnormalities. MR detected significantly more cryptococcosis-related lesions than CT for 17 patients who had had both investigations (76% vs. 24%, p = 0.005. In conclusion, MR appears more effective than CT for the evaluation of AIDS-associated cerebral cryptococcosis. Furthermore, brain imaging is an effective tool to assess the initial disease severity in this setting. Given this, we suggest that investigation for cryptococcosis-related lesions is merited, even in the absence of neurological abnormality, if a high fungal burden is suspected on the basis of high serum and/or CSF antigen titers.

  2. Evidence of end-effector based gait machines in gait rehabilitation after CNS lesion.

    Science.gov (United States)

    Hesse, S; Schattat, N; Mehrholz, J; Werner, C

    2013-01-01

    A task-specific repetitive approach in gait rehabilitation after CNS lesion is well accepted nowadays. To ease the therapists' and patients' physical effort, the past two decades have seen the introduction of gait machines to intensify the amount of gait practice. Two principles have emerged, an exoskeleton- and an endeffector-based approach. Both systems share the harness and the body weight support. With the end-effector-based devices, the patients' feet are positioned on two foot plates, whose movements simulate stance and swing phase. This article provides an overview on the end-effector based machine's effectiveness regarding the restoration of gait. For the electromechanical gait trainer GT I, a meta analysis identified nine controlled trials (RCT) in stroke subjects (n = 568) and were analyzed to detect differences between end-effector-based locomotion + physiotherapy and physiotherapy alone. Patients practising with the machine effected in a superior gait ability (210 out of 319 patients, 65.8% vs. 96 out of 249 patients, 38.6%, respectively, Z = 2.29, p = 0.020), due to a larger training intensity. Only single RCTs have been reported for other devices and etiologies. The introduction of end-effector based gait machines has opened a new succesful chapter in gait rehabilitation after CNS lesion.

  3. Betel quid oral lichenoid lesions: a hospital based cross-sectional study.

    Science.gov (United States)

    Arya, Sugandha; Vengal, Manoj; Raju, Bina; Patil, Neelkant; Sathosker, Sujatha; Bateja, Sumit; David, Jamil

    2017-02-01

    The aim of this study was to assess the prevalence and risk indicators of betel quid oral lichenoid lesions in chewers. A total of 1209 chewers were identified and categorized into three main groups based on the type of lesion: betel quid oral lichenoid lesions only, betel quid oral lichenoid lesions in association with quid-induced other oral mucosal lesions, and no lesions. Multinomial regression analyses were used to determine associations between dependent and independent variables. Betel quid oral lichenoid lesions were more common in individuals who chewed quid comprising both tobacco and areca nut, and in those who chewed it two to three, or greater than three, times a day. Betel quid oral lichenoid lesions + quid-induced other oral mucosal lesions were more likely to occur in females, and in individuals who chewed quid containing both tobacco and areca nut, in their processed and unprocessed forms, and greater than three times a day. The prevalence of betel quid oral lichenoid lesions was higher than that reported in previous studies conducted in India. Increase in the frequency and duration of quid chewing was associated with increased likelihood of developing these oral lichenoid lesions. © 2015 Wiley Publishing Asia Pty Ltd.

  4. Effect of MTA-based sealer on the healing of periapical lesions

    Directory of Open Access Journals (Sweden)

    Joao Eduardo GOMES-FILHO

    2013-06-01

    Full Text Available Some manufacturers have recently added specific components to improve the ease of handling and insertion material properties of MTA in order to create MTA-based sealers. Objective The aim of this study was to evaluate the healing of periapical lesions in canine teeth after a single session of endodontic treatment with MTA Fillapex® compared with Sealapex® or Endo-CPM-Sealer®. Material and Methods Sixty-two root canals were performed on two 1-year-old male dogs. After coronal access and pulp extirpation, the canals were exposed to the oral cavity for 6 months in order to induce periapical lesions. The root canals were prepared, irrigated with a solution of 2.5% sodium hypochlorite and filled with gutta-percha and different sealers, according to the following groups: 1 Sealapex®; 2 Endo-CPM-Sealer®; and 3 MTA Fillapex®. Some teeth with periapical lesions were left untreated for use as positive controls. Healthy teeth were used as negative controls. After 6 months, the animals were sacrificed and serial sections from the roots were prepared for histomorphologic analysis and stained with hematoxylin and eosin and the Brown and Brenn technique. The lesions were scored according to pre-established histomorphologic parameters and the scores statistically analyzed using the Kruskal-Wallis test. Results All 3 materials produced similar patterns of healing (p>0.05; in particular, persistent inflammation and absence of complete periapical tissue healing were consistently noted. Conclusions Preparation of the infected root canals followed by filling with the materials studied was insufficient to provide complete healing of the periapical tissues.

  5. Effect of MTA-based sealer on the healing of periapical lesions.

    Science.gov (United States)

    Gomes-Filho, João Eduardo; Watanabe, Simone; Cintra, Luciano Tavares Angelo; Nery, Mauro Juvenal; Dezan-Júnior, Eloi; Queiroz, India Olinta Azevedo; Lodi, Carolina Simonetti; Basso, Maria Daniela

    2013-01-01

    Some manufacturers have recently added specific components to improve the ease of handling and insertion material properties of MTA in order to create MTA-based sealers. The aim of this study was to evaluate the healing of periapical lesions in canine teeth after a single session of endodontic treatment with MTA Fillapex® compared with Sealapex® or Endo-CPM-Sealer®. Sixty-two root canals were performed on two 1-year-old male dogs. After coronal access and pulp extirpation, the canals were exposed to the oral cavity for 6 months in order to induce periapical lesions. The root canals were prepared, irrigated with a solution of 2.5% sodium hypochlorite and filled with gutta-percha and different sealers, according to the following groups: 1) Sealapex®; 2) Endo-CPM-Sealer®; and 3) MTA Fillapex®. Some teeth with periapical lesions were left untreated for use as positive controls. Healthy teeth were used as negative controls. After 6 months, the animals were sacrificed and serial sections from the roots were prepared for histomorphologic analysis and stained with hematoxylin and eosin and the Brown and Brenn technique. The lesions were scored according to pre-established histomorphologic parameters and the scores statistically analyzed using the Kruskal-Wallis test. All 3 materials produced similar patterns of healing (p>0.05); in particular, persistent inflammation and absence of complete periapical tissue healing were consistently noted. Preparation of the infected root canals followed by filling with the materials studied was insufficient to provide complete healing of the periapical tissues.

  6. CT-based needle marking of superficial intracranial lesions for minimal invasive neurosurgery

    International Nuclear Information System (INIS)

    Marquardt, G.; Wolff, R.; Schick, U.; Lorenz, R.

    2000-01-01

    A CT-based method of marking superficial intracranial lesions with a needle is presented. This form of neuronavigation can be applied in every neurosurgical centre. Owing to its rapid application it is also suitable for cases of emergency. The neurosurgical approach can be centred precisely over this lesion providing for a minimally invasive operation. The method has proved its efficacy in numerous cases of haematomas and cystic lesions. (author)

  7. Recurrence of cervical intraepithelial lesions after thermo-coagulation in HIV-positive and HIV-negative Nigerian women.

    Science.gov (United States)

    Oga, Emmanuel A; Brown, Jessica P; Brown, Clayton; Dareng, Eileen; Adekanmbi, Victor; Odutola, Michael; Olaniyan, Olayinka; Offiong, Richard; Obende, Kayode; Adewole, Ayodele Stephen; Peter, Achara; Dakum, Patrick; Adebamowo, Clement

    2016-05-11

    The burden of cervical cancer remains huge globally, more so in sub-Saharan Africa. Effectiveness of screening, rates of recurrence following treatment and factors driving these in Africans have not been sufficiently studied. The purpose of this study therefore was to investigate factors associated with recurrence of cervical intraepithelial lesions following thermo-coagulation in HIV-positive and HIV-negative Nigerian women using Visual Inspection with Acetic Acid (VIA) or Lugol's Iodine (VILI) for diagnosis. A retrospective cohort study was conducted, recruiting participants from the cervical cancer "see and treat" program of IHVN. Data from 6 sites collected over a 4-year period was used. Inclusion criteria were: age ≥18 years, baseline HIV status known, VIA or VILI positive and thermo-coagulation done. Logistic regression was performed to examine the proportion of women with recurrence and to examine factors associated with recurrence. Out of 177 women included in study, 67.8 % (120/177) were HIV-positive and 32.2 % (57/177) were HIV-negative. Recurrence occurred in 16.4 % (29/177) of participants; this was 18.3 % (22/120) in HIV-positive women compared to 12.3 % (7/57) in HIV-negative women but this difference was not statistically significant (p-value 0.31). Women aged ≥30 years were much less likely to develop recurrence, adjusted OR = 0.34 (95 % CI = 0.13, 0.92). Among HIV-positive women, CD4 count thermo-coagulation occurs in a significant proportion of women. HIV-positive women with low CD4 counts are at increased risk of recurrent lesions and may be related to immunosuppression.

  8. Frequency of fungal infection in biopsies of oral mucosal lesions: A prospective hospital-based study

    Directory of Open Access Journals (Sweden)

    Thimmarasa Venkappa Bhovi

    2015-01-01

    Full Text Available Aims and Objectives: To determine the frequency and common site of fungal infection in biopsies of oral mucosal lesions and also to detect the lesions most likely to be infected with fungal infection. Materials and Methods: A total of 100 patients with oral mucosal lesions were advised routine hematological examination followed by incisional biopsy under local anesthesia. The specimen were fixed in 10% neutral buffered formalin and processed. One section from the specimen was stained with hematoxylin and eosin staining for histopathological diagnosis of the lesion and a second section was stained with Periodic acid-Schiff (PAS stain for detection of fungal infection. Results: Out of the 100 patients, the most common mucosal lesion encountered was carcinoma (56% followed by lesions with dysplastic changes (28%, benign lesions (9%, squamous papilloma (2% and oral submucous fibrosis (5%. The most common anatomic location affected by the mucosal lesions were buccal mucosa, followed by the tongue, gingiva, maxillary tuberosity and floor of the mouth with values of 73%, 16%, 6%, 4% and 1%, respectively. Squamous papilloma had the highest positive association with fungal infection (100% followed by lesions with dysplastic changes (17.9% and carcinoma (8.9%. The maximum fungal positive association was encountered in the mucosal lesions over the tongue (18.7% followed by the buccal mucosa (12.3%. Conclusion: There is statistically significant association of fungal infection with dysplastic lesions and papilloma with the tongue and buccal mucosa as the most common sites. Hence a PAS stain should be performed whenever epithelial dysplasia on the tongue and buccal mucosa is diagnosed.

  9. GTV-based prescription in SBRT for lung lesions using advanced dose calculation algorithms

    International Nuclear Information System (INIS)

    Lacornerie, Thomas; Lisbona, Albert; Mirabel, Xavier; Lartigau, Eric; Reynaert, Nick

    2014-01-01

    The aim of current study was to investigate the way dose is prescribed to lung lesions during SBRT using advanced dose calculation algorithms that take into account electron transport (type B algorithms). As type A algorithms do not take into account secondary electron transport, they overestimate the dose to lung lesions. Type B algorithms are more accurate but still no consensus is reached regarding dose prescription. The positive clinical results obtained using type A algorithms should be used as a starting point. In current work a dose-calculation experiment is performed, presenting different prescription methods. Three cases with three different sizes of peripheral lung lesions were planned using three different treatment platforms. For each individual case 60 Gy to the PTV was prescribed using a type A algorithm and the dose distribution was recalculated using a type B algorithm in order to evaluate the impact of the secondary electron transport. Secondly, for each case a type B algorithm was used to prescribe 48 Gy to the PTV, and the resulting doses to the GTV were analyzed. Finally, prescriptions based on specific GTV dose volumes were evaluated. When using a type A algorithm to prescribe the same dose to the PTV, the differences regarding median GTV doses among platforms and cases were always less than 10% of the prescription dose. The prescription to the PTV based on type B algorithms, leads to a more important variability of the median GTV dose among cases and among platforms, (respectively 24%, and 28%). However, when 54 Gy was prescribed as median GTV dose, using a type B algorithm, the variability observed was minimal. Normalizing the prescription dose to the median GTV dose for lung lesions avoids variability among different cases and treatment platforms of SBRT when type B algorithms are used to calculate the dose. The combination of using a type A algorithm to optimize a homogeneous dose in the PTV and using a type B algorithm to prescribe the

  10. SLAM - Based Approach to Dynamic Ship Positioning

    Directory of Open Access Journals (Sweden)

    Krzysztof Wrobel

    2014-03-01

    Full Text Available Dynamically positioned vessels, used by offshore industry, use not only satellite navigation but also different positioning systems, often referred to as reference' systems. Most of them use multiple technical devices located outside the vessel which creates some problems with their accessibility and performance. In this paper, a basic concept of reference system independent from any external device is presented, basing on hydroacoustics and Simultaneous Localization and Mapping (SLAM method. Theoretical analysis of its operability is also performed.

  11. Cauda equina enhancing lesion in a HIV-positive patient. Case report and literature revision.

    Directory of Open Access Journals (Sweden)

    Pasquale De Bonis

    2011-10-01

    Full Text Available We describe the case a spinal cord localization of neurological toxoplasmosis in a HIV-positive patient with Burkitt lymphoma, previously treated with chemotherapy and immunotherapy. This complication occurred while patient was in complete remission of lymphoma, with CD4+ T cell count of 270 /ml, undetectable HIV viremia, and despite the trimethoprim/ sulfamethoxazole prophylaxis. Indeed, we hypothesize that in our patient neurologic toxoplasmosis has been fostered more by previous immuno-chemotherapy than by HIV- related immunodeficiency. On the whole, this case suggests that parameters usually employed to predict the risk for opportunistic infections in HIV-positive people might not apply to patients with HIV-related lymphomas.

  12. Vehicle positioning based on UWB technology

    Science.gov (United States)

    Hu, Siquan; Kang, Min; She, Chundong

    2017-08-01

    In recent years, with the rapid increase of the number of urban cars, the vehicle internet is becoming a trend of smart transportion. In such vehicle network, accurate location is very crucial in many new applications such as autopilot, semi-autopilot and Car-to-x communications. UWB technology has been used for indoor closed range positioning and ranging widely, while UWB outdoor positioning and ranging research is relatively less. This paper proposed UWB as the vehicle positioning technology and developed a method based on two-way-ranging (TWR) to solve the ranging problem between vehicles. At the same time, the improved TOA method was used to locate vehicles, which has higher precision compared with traditional GPS or LBS. A hardware module is introduced and the simulation results show that the modules are capable of precise positioning for vehicles in vehicle network.

  13. Airborne relay-based regional positioning system.

    Science.gov (United States)

    Lee, Kyuman; Noh, Hongjun; Lim, Jaesung

    2015-05-28

    Ground-based pseudolite systems have some limitations, such as low vertical accuracy, multipath effects and near-far problems. These problems are not significant in airborne-based pseudolite systems. However, the monitoring of pseudolite positions is required because of the mobility of the platforms on which the pseudolites are mounted, and this causes performance degradation. To address these pseudolite system limitations, we propose an airborne relay-based regional positioning system that consists of a master station, reference stations, airborne relays and a user. In the proposed system, navigation signals are generated from the reference stations located on the ground and are relayed via the airborne relays. Unlike in conventional airborne-based systems, the user in the proposed system sequentially estimates both the locations of airborne relays and his/her own position. Therefore, a delay due to monitoring does not occur, and the accuracy is not affected by the movement of airborne relays. We conducted several simulations to evaluate the performance of the proposed system. Based on the simulation results, we demonstrated that the proposed system guarantees a higher accuracy than airborne-based pseudolite systems, and it is feasible despite the existence of clock offsets among reference stations.

  14. Cauda equina enhancing lesion in a HIV-positive patient. Case report and literature revision.

    Directory of Open Access Journals (Sweden)

    Luigi Maria Larocca

    2011-01-01

    Full Text Available

    We describe the case a spinal cord localization of neurological toxoplasmosis in a HIV-positive patient with Burkitt lymphoma, previously treated with chemotherapy and immunotherapy. This complication occurred while patient was in complete remission of lymphoma, with CD4+ T cell count of 270 /ml, undetectable HIV viremia, and despite the trimethoprim/ sulfamethoxazole prophylaxis. Indeed, we hypothesize that in our patient neurologic toxoplasmosis has been fostered more by previous immuno-chemotherapy than by HIV- related immunodeficiency. On the whole, this case suggests that parameters usually employed to predict the risk for opportunistic infections in HIV-positive people might not apply to patients with HIV-related lymphomas.

  15. The role of smoking and alcohol intake in the development of high-grade squamous intraepithelial lesions among high-risk HPV-positive women

    DEFF Research Database (Denmark)

    Tolstrup, Janne; Munk, Christian; Thomsen, Birthe Lykke

    2006-01-01

    BACKGROUND: Infection with human papillomavirus is considered a necessary factor in developing high-grade squamous intraepithelial lesions of the cervix. However, most human papillomavirus positive women do not develop high-grade squamous intraepithelial lesions and other factors may be important...... for this transition. The objective of the present study was to examine if smoking and alcohol intake are associated with the risk of developing high-grade squamous intraepithelial lesions in women positive for high-risk human papillomavirus types. METHODS: We used baseline information on exposures on 548 high......-risk human papillomavirus positive women with normal cytology, comparing 94 women who developed high-grade squamous intraepithelial lesions with 454 women who remained cytologically normal. Logistic regression was applied for statistical analysis. RESULTS: Compared with never smokers, the odds ratio for high...

  16. Imaging spectrum and pitfalls of 11C-methionine position emission tomography in a series of patients with intracranial lesions

    International Nuclear Information System (INIS)

    Ito, Kimiteru; Matsuda, Hiroshi; Kubota, Kazoo

    2016-01-01

    11 C-methionine (Met) positron emission tomography (PET) is one of the most commonly used PET tracers for evaluating brain tumors. However, few reports have described tips and pitfalls of 11 C-Met PET for general practitioners. Physiological 11 C-Met uptake, anatomical variations, vascular disorders, non-tumorous lesions such as inflammation or dysplasia, benign brain tumors and patient condition during 11 C-Met PET examination can potentially affect the image interpretation and cause false positives and negatives. These pitfalls in the interpretation of 11 C-Met PET images are important for not only nuclear medicine physicians but also general radiologists. Familiarity with the spectrum and pitfalls of 11 C-Met images could help prevent unfavorable clinical results caused by misdiagnoses

  17. Clinical and angiographic predictors of haemodynamically significant angiographic lesions: development and validation of a risk score to predict positive fractional flow reserve.

    Science.gov (United States)

    Sareen, Nishtha; Baber, Usman; Kezbor, Safwan; Sayseng, Sonny; Aquino, Melissa; Mehran, Roxana; Sweeny, Joseph; Barman, Nitin; Kini, Annapoorna; Sharma, Samin K

    2017-04-07

    Coronary revascularisation based upon physiological evaluation of lesions improves clinical outcomes. Angiographic or visual stenosis assessment alone is insufficient in predicting haemodynamic stenosis severity by fractional flow reserve (FFR) and therefore cannot be used to guide revascularisation, particularly in the lesion subset system formulated. Of 1,023 consecutive lesions (883 patients), 314 (31%) were haemodynamically significant. Characteristics associated with FFR ≤0.8 include male gender, higher SYNTAX score, lesions ≥20 mm, stenosis >50%, bifurcation, calcification, absence of tortuosity and smaller reference diameter. A user-friendly integer score was developed with the five variables demonstrating the strongest association. On prospective validation (in 279 distinct lesions), the increasing value of the score correlated well with increasing haemodynamic significance (C-statistic 0.85). We identified several clinical and angiographic characteristics and formulated a scoring system to guide the approach to intermediate lesions. This may translate into cost savings. Larger studies with prospective validation are required to confirm our results.

  18. Evaluation of MR lymphography with positive lymphotropic contrast agent in diagnosing lymph node lesions

    International Nuclear Information System (INIS)

    Zhou Zhengyang; Yu Haiping; Chen Junkun; Zhu Bin

    2010-01-01

    Objective: To evaluate the interstital MR lymphography using positive lymphotropic contrast agent for differentiation of metastatic lymph nodes from inflammatory lymph nodes hyperplasm. Methods: Eighteen New Zealand white rabbits weighted at 2. 0-2. 5 kg were used. Inflammatory hyperplastic popliteal lymph node model was established in 9 rabbits by injection of complete freund adjuvant into the interdigitial skin of the dorsal aspect of one hind leg, and tumor-bearing popliteal lymph node model was established in another 9 rabbits by injection of VX2 tumor cell suspension. The popliteal lymph nodes of another hind leg of all 18 rabbits were assigned to the normal contral group. In each group, every rabbit underwent MR lymphography examination before and after the inoculation. Volumes of 0.2 ml of Gd [ DTPA-bis ( 2-aminoethoxy ) ethane ] polymeric contrast agent ( Gd-poly-DTPA-EOEA ) injection were injected subcutaneously into the dorsal feet of both hind legs of two groups of rabbits. T 1 -weighted 3D gradient-echo images were obtained, and source images were used to reconstruct images of MIP before and after the administration of agent. The maximum short-axis diameter (MSAD) of each popliteal lymph node was measured on the enhanced 3D MIP images, and the signal-to-noise ratio (SNR) measurement was performed in the largest popliteal node of each rabbit at each time point in delayed scan. Independent- samples t test was used to compare the sizes of popliteal nodes in MSADs between inflammatorily hyperplastic and tumor-bearing nodes after the inoculation, and the values of SNRs of popliteal nodes at each time point between inflammatorily hyperplastic, tumor-bearing and normal popliteal lymph nodes. Imaging results of the popliteal nodes were analyzed and correlated with pathological findings. Results: All of the rabbits were successfully inoculated except of the 2 rabbits in tumor-bearing nodal group. The size in MSAD of 13 inflammatorily hyperplastic and 11 tumor

  19. An evidence-based review for the management of cystic pancreatic lesions

    International Nuclear Information System (INIS)

    Planner, A.C.; Anderson, E.M.; Slater, A.; Phillips-Hughes, J.; Bungay, H.K.; Betts, M.

    2007-01-01

    The incidental finding of pancreatic cysts is becoming more common because of the increased use of cross-sectional imaging. As a result, the perspective from historical series of symptomatic patients is not always applicable to the current cohort of patients with cystic lesions in their pancreas. In this review, the characteristic radiological features that aid diagnosis are highlighted, and the complementary role of different imaging methods and the appropriate use of tissue sampling are identified. Based on the literature regarding the diagnostic role of imaging in characterizing cystic pancreatic lesions, it is possible to recommend a practical imaging algorithm for the diagnosis of cystic pancreatic lesions

  20. Health Physics Positions Data Base: Revision 1

    International Nuclear Information System (INIS)

    Kerr, G.D.; Borges, T.; Stafford, R.S.; Lu, P.Y.; Carter, D.

    1994-02-01

    The Health Physics Positions (HPPOS) Data Base of the Nuclear Regulatory Commission (NRC) is a collection of NRC staff positions on a wide range of topics involving radiation protection (health physics). It consists of 328 documents in the form of letters, memoranda, and excerpts from technical reports. The HPPOS Data Base was developed by the NRC Headquarters and Regional Offices to help ensure uniformity in inspections, enforcement, and licensing actions. Staff members of the Oak Ridge National Laboratory (ORNL) have assisted the NRC staff in summarizing the documents during the preparation of this NUREG report. These summaries are also being made available as a open-quotes stand aloneclose quotes software package for IBM and IBM-compatible personal computers. The software package for this report is called HPPOS Version 2.0. A variety of indexing schemes were used to increase the usefulness of the NUREG report and its associated software. The software package and the summaries in the report are written in the context of the open-quotes newclose quotes 10 CFR Part 20 (section section 20.1001--20.2401). The purpose of this NUREG report is to allow interested individuals to familiarize themselves with the contents of the HPPOS Data Base and with the basis of many NRC decisions and regulations. The HPPOS summaries and original documents are intended to serve as a source of information for radiation protection programs at nuclear research and power reactors, nuclear medicine, and other industries that either process or use nuclear materials

  1. Mass lesions in chronic pancreatitis: benign or malignant? An "evidence-based practice" approach.

    LENUS (Irish Health Repository)

    Gerstenmaier, Jan F

    2012-02-01

    The diagnosis of a pancreatic mass lesion in the presence of chronic pancreatitis can be extremely challenging. At the same time, a high level of certainty about the diagnosis is necessary for appropriate management planning. The aim of this study was to establish current best evidence about which imaging methods reliably differentiate a benign from a malignant lesion, and show how that evidence is best applied. A diagnostic algorithm based on Bayesian analysis is proposed.

  2. Radio-isotope scanning using labelled bleomycin in positive and differential diagnosis of primary and secondary malignant pulmonary lesions

    International Nuclear Information System (INIS)

    Robert, J.; Bertrand, A.; Nouel, J.P.; Witz, H.

    1975-01-01

    A lung scan using bleomycin labelled with cobalt 57 was carried out in 308 patients representing 191 primary malignant tumours, 48 pulmonary metastases and 69 benign lesions. The primary and secondary malignant lesions always gave rise to a hyperactive focus except in 8 cases of primary lung tumour. The negative examination may be explained, either by the small size of the lesion or by radiotherapy in progress. Among the benign lesions, only advanced tuberculosis and very inflammatory lung diseases frequently took up labelled bleomycin (15 hyperactive foci out of 69 benign lesions). Quantitative measurements, i.e. ratio of the lesional activity/activity of healthy lung tissue, were carried out in all patients. The malignant lesions were usually more active than the benign lesions. There was no definite correlation between the uptake of labelled bleomycin and the histological nature of the lesion. However, undifferentiated and anaplastic carcinomas were often more active. One should emphasize that these results show that a hyperactive focus has a 94% chance of being a carcinoma. The absence of bleomycin uptake means that there is a 92% chance of a benign lesion [fr

  3. Environmental enrichment brings a beneficial effect on beam walking and enhances the migration of doublecortin-positive cells following striatal lesions in rats.

    Science.gov (United States)

    Urakawa, S; Hida, H; Masuda, T; Misumi, S; Kim, T-S; Nishino, H

    2007-02-09

    Rats raised in an enriched environment (enriched rats) have been reported to show less motor dysfunction following brain lesions, but the neuronal correlates of this improvement have not been well clarified. The present study aimed to elucidate the effect of chemical brain lesions and environmental enrichment on motor function and lesion-induced neurogenesis. Three week-old, recently weaned rats were divided into two groups: one group was raised in an enriched environment and the other group was raised in a standard cage for 5 weeks. Striatal damage was induced at an age of 8 weeks by injection of the neuro-toxins 6-hydroxydopamine (6-OHDA) or quinolinic acid (QA) into the striatum, or by injection of 6-OHDA into the substantia nigra (SN), which depleted nigrostriatal dopaminergic innervation. Enriched rats showed better performance on beam walking compared with those raised in standard conditions, but both groups showed similar forelimb use asymmetry in a cylinder test. The number of bromodeoxyuridine-labeled proliferating cells in the subventricular zone was increased by a severe striatal lesion induced by QA injection 1 week after the lesion, but decreased by injection of 6-OHDA into the SN. Following induction of lesions by striatal injection of 6-OHDA or QA, the number of cells positive for doublecortin (DCX) was strongly increased in the striatum; however, there was no change in the number of DCX-positive cells following 6-OHDA injection into the SN. Environmental enrichment enhanced the increase of DCX-positive cells with migrating morphology in the dorsal striatum. In enriched rats, DCX-positive cells traversed the striatal parenchyma far from the corpus callosum and lateral ventricle. DCX-positive cells co-expressed an immature neuronal marker, polysialylated neural cell adhesion molecule, but were negative for a glial marker. These data suggest that environmental enrichment improves motor performance on beam walking and enhances neuronal migration toward

  4. An Evaluation by Midwives and Gynecologists of Treatability of Cervical Lesions by Cryotherapy Among Human Papillomavirus–Positive Women

    Science.gov (United States)

    Gage, Julia C.; Rodriguez, Ana Cecilia; Schiffman, Mark; Adadevoh, Sydney; Alvarez Larraondo, Manuel J.; Chumworathayi, Bandit; Lejarza, Sandra Vargas; Araya, Luis Villegas; Garcia, Francisco; Budihas, Scott R.; Long, Rodney; Katki, Hormuzd A.; Herrero, Rolando; Burk, Robert D.; Jeronimo, Jose

    2010-01-01

    Objectives To estimate efficacy of a visual triage of human papillomavirus (HPV)– positive women to either immediate cryotherapy or referral if not treatable (eg, invasive cancer, large precancers). Methods We evaluated visual triage in the HPV-positive women aged 25 to 55 years from the 10,000-woman Guanacaste Cohort Study (n = 552). Twelve Peruvian midwives and 5 international gynecologists assessed treatability by cryotherapy using digitized high-resolution cervical images taken at enrollment. The reference standard of treatability was determined by 2 lead gynecologists from the entire 7-year follow-up of the women. Women diagnosed with histologic cervical intraepithelial neoplasia grade 2 or worse or 5-year persistence of carcinogenic HPV infection were defined as needing treatment. Results Midwives and gynecologists judged 30.8% and 41.2% of women not treatable by cryotherapy, respectively (P cryotherapy. The proportion of women judged not treatable by a reviewer varied widely and ranged from 18.6%to 61.1%. Interrater agreement was poor with mean pairwise overall agreement of 71.4% and 66.3% and κ ’s of 0.33 and 0.30 for midwives and gynecologists, respectively. Conclusions In future “screen-and-treat” cervical cancer prevention programs using HPV testing and cryotherapy, practitioners will visually triage HPV-positive women. The suboptimal performance of visual triage suggests that screen-and-treat programs using cryotherapy might be insufficient for treating precancerous lesions. Improved, low-technology triage methods and/or improved safe and low-technology treatment options are needed. PMID:19509579

  5. An evaluation by midwives and gynecologists of treatability of cervical lesions by cryotherapy among human papillomavirus-positive women.

    Science.gov (United States)

    Gage, Julia C; Rodriguez, Ana Cecilia; Schiffman, Mark; Adadevoh, Sydney; Larraondo, Manuel J Alvarez; Chumworathayi, Bandit; Lejarza, Sandra Vargas; Araya, Luis Villegas; Garcia, Francisco; Budihas, Scott R; Long, Rodney; Katki, Hormuzd A; Herrero, Rolando; Burk, Robert D; Jeronimo, Jose

    2009-05-01

    To estimate efficacy of a visual triage of human papillomavirus (HPV)-positive women to either immediate cryotherapy or referral if not treatable (eg, invasive cancer, large precancers). We evaluated visual triage in the HPV-positive women aged 25 to 55 years from the 10,000-woman Guanacaste Cohort Study (n = 552). Twelve Peruvian midwives and 5 international gynecologists assessed treatability by cryotherapy using digitized high-resolution cervical images taken at enrollment. The reference standard of treatability was determined by 2 lead gynecologists from the entire 7-year follow-up of the women. Women diagnosed with histologic cervical intraepithelial neoplasia grade 2 or worse or 5-year persistence of carcinogenic HPV infection were defined as needing treatment. Midwives and gynecologists judged 30.8% and 41.2% of women not treatable by cryotherapy, respectively (P cryotherapy. The proportion of women judged not treatable by a reviewer varied widely and ranged from 18.6% to 61.1%. Interrater agreement was poor with mean pairwise overall agreement of 71.4% and 66.3% and kappa's of 0.33 and 0.30 for midwives and gynecologists, respectively. In future "screen-and-treat" cervical cancer prevention programs using HPV testing and cryotherapy, practitioners will visually triage HPV-positive women. The suboptimal performance of visual triage suggests that screen-and-treat programs using cryotherapy might be insufficient for treating precancerous lesions. Improved, low-technology triage methods and/or improved safe and low-technology treatment options are needed.

  6. A Method for Extracting Suspected Parotid Lesions in CT Images using Feature-based Segmentation and Active Contours based on Stationary Wavelet Transform

    Science.gov (United States)

    Wu, T. Y.; Lin, S. F.

    2013-10-01

    Automatic suspected lesion extraction is an important application in computer-aided diagnosis (CAD). In this paper, we propose a method to automatically extract the suspected parotid regions for clinical evaluation in head and neck CT images. The suspected lesion tissues in low contrast tissue regions can be localized with feature-based segmentation (FBS) based on local texture features, and can be delineated with accuracy by modified active contour models (ACM). At first, stationary wavelet transform (SWT) is introduced. The derived wavelet coefficients are applied to derive the local features for FBS, and to generate enhanced energy maps for ACM computation. Geometric shape features (GSFs) are proposed to analyze each soft tissue region segmented by FBS; the regions with higher similarity GSFs with the lesions are extracted and the information is also applied as the initial conditions for fine delineation computation. Consequently, the suspected lesions can be automatically localized and accurately delineated for aiding clinical diagnosis. The performance of the proposed method is evaluated by comparing with the results outlined by clinical experts. The experiments on 20 pathological CT data sets show that the true-positive (TP) rate on recognizing parotid lesions is about 94%, and the dimension accuracy of delineation results can also approach over 93%.

  7. Health Physics Positions Data Base: Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, G.D.; Borges, T.; Stafford, R.S.; Lu, P.Y. [Oak Ridge National Lab., TN (United States); Carter, D. [US Nuclear Regulatory Commission, Washington, DC (United States)

    1994-02-01

    The Health Physics Positions (HPPOS) Data Base of the Nuclear Regulatory Commission (NRC) is a collection of NRC staff positions on a wide range of topics involving radiation protection (health physics). It consists of 328 documents in the form of letters, memoranda, and excerpts from technical reports. The HPPOS Data Base was developed by the NRC Headquarters and Regional Offices to help ensure uniformity in inspections, enforcement, and licensing actions. Staff members of the Oak Ridge National Laboratory (ORNL) have assisted the NRC staff in summarizing the documents during the preparation of this NUREG report. These summaries are also being made available as a {open_quotes}stand alone{close_quotes} software package for IBM and IBM-compatible personal computers. The software package for this report is called HPPOS Version 2.0. A variety of indexing schemes were used to increase the usefulness of the NUREG report and its associated software. The software package and the summaries in the report are written in the context of the {open_quotes}new{close_quotes} 10 CFR Part 20 ({section}{section}20.1001--20.2401). The purpose of this NUREG report is to allow interested individuals to familiarize themselves with the contents of the HPPOS Data Base and with the basis of many NRC decisions and regulations. The HPPOS summaries and original documents are intended to serve as a source of information for radiation protection programs at nuclear research and power reactors, nuclear medicine, and other industries that either process or use nuclear materials.

  8. Quantifying the margin sharpness of lesions on radiological images for content-based image retrieval

    International Nuclear Information System (INIS)

    Xu Jiajing; Napel, Sandy; Greenspan, Hayit; Beaulieu, Christopher F.; Agrawal, Neeraj; Rubin, Daniel

    2012-01-01

    . Equivalence across deformations was assessed using Schuirmann's paired two one-sided tests. Results: In simulated images, the concordance correlation between measured gradient and actual gradient was 0.994. The mean (s.d.) and standard deviation NDCG score for the retrieval of K images, K = 5, 10, and 15, were 84% (8%), 85% (7%), and 85% (7%) for CT images containing liver lesions, and 82% (7%), 84% (6%), and 85% (4%) for CT images containing lung nodules, respectively. The authors’ proposed method outperformed the two existing margin characterization methods in average NDCG scores over all K, by 1.5% and 3% in datasets containing liver lesion, and 4.5% and 5% in datasets containing lung nodules. Equivalence testing showed that the authors’ feature is more robust across all margin deformations (p < 0.05) than the two existing methods for margin sharpness characterization in both simulated and clinical datasets. Conclusions: The authors have described a new image feature to quantify the margin sharpness of lesions. It has strong correlation with known margin sharpness in simulated images and in clinical CT images containing liver lesions and lung nodules. This image feature has excellent performance for retrieving images with similar margin characteristics, suggesting potential utility, in conjunction with other lesion features, for content-based image retrieval applications.

  9. KIT D816V mutation-positive cell fractions in lesional skin biopsies from adults with systemic mastocytosis

    DEFF Research Database (Denmark)

    Kielsgaard Kristensen, Thomas; Broesby-Olsen, Sigurd; Vestergaard, Hanne

    2013-01-01

    Most adults with systemic mastocytosis (SM) carry the somatic KIT D816V mutation, but the occurrence of the mutation in lesional skin remains to be characterized.......Most adults with systemic mastocytosis (SM) carry the somatic KIT D816V mutation, but the occurrence of the mutation in lesional skin remains to be characterized....

  10. Association between lesion location and language function in adult glioma using voxel-based lesion-symptom mapping

    Directory of Open Access Journals (Sweden)

    Pia Banerjee

    2015-01-01

    Conclusions: Our findings identify the key anatomic structures involved in language functioning in adult glioma patients using an innovative lesion analysis technique and suggest that expressive language abilities may be more task-dependent and distributed than receptive language abilities.

  11. Positive predictive value of additional synchronous breast lesions in whole-breast ultrasonography at the diagnosis of breast cancer: clinical and imaging factors

    International Nuclear Information System (INIS)

    Kim, Ah Hyun; Kim, Min Jung; Kim, Eun Kyung; Moon, Hee Jung; Park, Hee Jung

    2014-01-01

    To evaluate the positive predictive value (PPV) of bilateral whole-breast ultrasonography (BWBU) for detection of synchronous breast lesions on initial diagnosis of breast cancer and evaluate factors affecting the PPV of BWBU according to varying clinicoimaging factors. A total of 75 patients who had synchronous lesions with pathologic confirmation at the initial diagnosis of breast cancer during January 2007 and December 2007 were included. The clinical factors of the patients were evaluated. One observer retrospectively reviewed the imaging studies of the index breast cancer lesion and the synchronous lesion. The PPV for additional biopsy was calculated for BWBU and various clinical and imaging factors affecting the PPV for BWBU were evaluated. The overall PPV for additional biopsy was 25.7% (18 of 70). The PPV for synchronous lesions detected both on mammography and BWBU, and detected only on BWBU, was 76.9% (10 of 13) and 14.3% (7 of 49), respectively. There was no clinical factor affecting the PPV for BWBU. Among the imaging factors, ipsilateral location of the synchronous lesion to the index lesion (P=0.06) showed a marginal statistically significant correlation with malignancy in the synchronous breast lesion. A mass with calcification on mammography presentation (P<0.01), presence of calcification among the ultrasonography findings (P<0.01), and high Breast Imaging Reporting and Data System final assessment (P<0.01) were imaging factors that were associated with malignancy in the additional synchronous lesion. BWBU can detect additional synchronous malignancy at the diagnosis of breast cancer with a relatively high PPV, especially when mammography findings are correlated with ultrasonographic findings.

  12. Wire Position Monitoring with FPGA based Electronics

    International Nuclear Information System (INIS)

    Eddy, N.; Lysenko, O.

    2009-01-01

    This fall the first Tesla-style cryomodule cooldown test is being performed at Fermilab. Instrumentation department is preparing the electronics to handle the data from a set of wire position monitors (WPMs). For simulation purposes a prototype pipe with a WMP has been developed and built. The system is based on the measurement of signals induced in pickups by 320 MHz signal carried by a wire through the WPM. The wire is stretched along the pipe with a tensioning load of 9.07 kg. The WPM consists of four 50 (Omega) striplines spaced 90 o apart. FPGA based digitizer scans the WPM and transmits the data to a PC via VME interface. The data acquisition is based on the PC running LabView. In order to increase the accuracy and convenience of the measurements some modifications were required. The first is implementation of an average and decimation filter algorithm in the integrator operation in the FPGA. The second is the development of alternative tool for WPM measurements in the PC. The paper describes how these modifications were performed and test results of a new design. The last cryomodule generation has a single chain of seven WPMs (placed in critical positions: at each end, at the three posts and between the posts) to monitor a cold mass displacement during cooldown. The system was developed in Italy in collaboration with DESY. Similar developments have taken place at Fermilab in the frame of cryomodules construction for SCRF research. This fall preliminary cryomodule cooldown test is being performed. In order to prepare an appropriate electronic system for the test a prototype pipe with a WMP has been developed and built, figure 1. The system is based on the measurement of signals induced in pickups by 320 MHz signal carried by a wire through the WPM. The 0.5 mm diameter Cu wire is stretched along the pipe with a tensioning load of 9.07 kg and has a length of 1.1 m. The WPM consists of four 50 (Omega) striplines spaced 90 o apart. An FPGA based digitizer

  13. Neural network ensemble based CAD system for focal liver lesions from B-mode ultrasound.

    Science.gov (United States)

    Virmani, Jitendra; Kumar, Vinod; Kalra, Naveen; Khandelwal, Niranjan

    2014-08-01

    A neural network ensemble (NNE) based computer-aided diagnostic (CAD) system to assist radiologists in differential diagnosis between focal liver lesions (FLLs), including (1) typical and atypical cases of Cyst, hemangioma (HEM) and metastatic carcinoma (MET) lesions, (2) small and large hepatocellular carcinoma (HCC) lesions, along with (3) normal (NOR) liver tissue is proposed in the present work. Expert radiologists, visualize the textural characteristics of regions inside and outside the lesions to differentiate between different FLLs, accordingly texture features computed from inside lesion regions of interest (IROIs) and texture ratio features computed from IROIs and surrounding lesion regions of interests (SROIs) are taken as input. Principal component analysis (PCA) is used for reducing the dimensionality of the feature space before classifier design. The first step of classification module consists of a five class PCA-NN based primary classifier which yields probability outputs for five liver image classes. The second step of classification module consists of ten binary PCA-NN based secondary classifiers for NOR/Cyst, NOR/HEM, NOR/HCC, NOR/MET, Cyst/HEM, Cyst/HCC, Cyst/MET, HEM/HCC, HEM/MET and HCC/MET classes. The probability outputs of five class PCA-NN based primary classifier is used to determine the first two most probable classes for a test instance, based on which it is directed to the corresponding binary PCA-NN based secondary classifier for crisp classification between two classes. By including the second step of the classification module, classification accuracy increases from 88.7 % to 95 %. The promising results obtained by the proposed system indicate its usefulness to assist radiologists in differential diagnosis of FLLs.

  14. Implementation of double-C-arm synchronous real-time X-ray positioning system computer aided for aspiration biopsy of small lung lesion

    International Nuclear Information System (INIS)

    Zhu Hong; Wang Dong; Ye Yukun; Zhou Yuan; Lu Jianfeng; Yang Jingyu; Wang Lining

    2007-01-01

    Objective: To evaluate the feasibility of a new type of real-time three-dimensional X-ray positioning system for aspiration biopsy of small lung lesions. Methods: Using X-ray imaging technology and X-ray collimator technology and combining with double-C-arm X-ray machine, two different synchronous real-time images were obtained from the vertical to the horizontal plane. Then, with the computer image processing and computer vision processing technologies, dynamic tracking for 3D information of a pulmonary lesion and the needle in aspiration, and the relative position of the two, were established. Results: There was no interference while the two imaging perpendicularly X-ray beam met, two synchronous real-time image acquisition and tracking of a lung lesion and a needle could be completed in free respiration. The average positioning system error was about 0.5 mm, the largest positioning error was about 1.0 mm, real-time display rate was 5 screen/sec. Conclusions: the establishment of a new type of double-C-arm synchronous real-time X-ray positioning system is feasible. It is available for the fast and accurate aspiration biopsy of small lung lesions. (authors)

  15. Estimation of the frequency of positive biopsies for cancer in patients with diagnosis by images of breast lesion BIRADS 3, Hospital Mexico, 2007-2009

    International Nuclear Information System (INIS)

    Obando Valverde, Aiza

    2013-01-01

    The histopathological findings have been described in patients with diagnosis by images of BIRADS 3, at the Hospital Mexico during the years 2007-2009. The histopathological findings have enrolled patients with diagnosis by images of lesion probably benign. The percentage of positive biopsies for cancer in patients BIRADS 3 was determined and compared the finding, with data found in the international literature. The stadium has been determined at the time of positive histopathological diagnosis for cancer in patients with breast lesions scheduled by images as BIRADS 3. The findings of the present study have recollected without enough evidence to justify taking biopsies, suggesting that conservative management would be sufficient for diagnosis approach of lesions BIRADS 3 [es

  16. Three-dimensional spatiotemporal features for fast content-based retrieval of focal liver lesions.

    Science.gov (United States)

    Roy, Sharmili; Chi, Yanling; Liu, Jimin; Venkatesh, Sudhakar K; Brown, Michael S

    2014-11-01

    Content-based image retrieval systems for 3-D medical datasets still largely rely on 2-D image-based features extracted from a few representative slices of the image stack. Most 2 -D features that are currently used in the literature not only model a 3-D tumor incompletely but are also highly expensive in terms of computation time, especially for high-resolution datasets. Radiologist-specified semantic labels are sometimes used along with image-based 2-D features to improve the retrieval performance. Since radiological labels show large interuser variability, are often unstructured, and require user interaction, their use as lesion characterizing features is highly subjective, tedious, and slow. In this paper, we propose a 3-D image-based spatiotemporal feature extraction framework for fast content-based retrieval of focal liver lesions. All the features are computer generated and are extracted from four-phase abdominal CT images. Retrieval performance and query processing times for the proposed framework is evaluated on a database of 44 hepatic lesions comprising of five pathological types. Bull's eye percentage score above 85% is achieved for three out of the five lesion pathologies and for 98% of query lesions, at least one same type of lesion is ranked among the top two retrieved results. Experiments show that the proposed system's query processing is more than 20 times faster than other already published systems that use 2-D features. With fast computation time and high retrieval accuracy, the proposed system has the potential to be used as an assistant to radiologists for routine hepatic tumor diagnosis.

  17. Cryotherapy for Intra- and Perianal High-Grade Squamous Intraepithelial Lesions in HIV-Positive Men who have Sex with Men

    NARCIS (Netherlands)

    Siegenbeek van Heukelom, Matthijs L.; Gosens, Karien C. M.; Prins, Jan M.; de Vries, Henry J. C.

    2018-01-01

    Background Available treatment options for anal high-grade squamous intraepithelial lesions (HSIL) in HIV-positive men who have sex with men (MSM) are limited by low response rates and frequent recurrences. Cryotherapy is an established therapeutic option for several pre-malignant skin disorders.

  18. Is a single direct MR arthrography series in ABER position as accurate in detecting anteroinferior labroligamentous lesions as conventional MR arthography?

    Energy Technology Data Exchange (ETDEWEB)

    Schreinemachers, Saskia A.; Hulst, Victor P.M. van der; Woude, Henk-Jan van der [Onze Lieve Vrouwe Gasthuis, Department of Radiology, Amsterdam (Netherlands); Jaap Willems, W. [Onze Lieve Vrouwe Gasthuis, Orthopaedic Surgery, Amsterdam (Netherlands); Bipat, Shandra [University of Amsterdam, Department of Radiology, Academic Medical Centre, Amsterdam (Netherlands)

    2009-07-15

    The purpose of this study is to retrospectively compare accuracy of single magnetic resonance (MR) arthrography series in Abduction External Rotation (ABER) with conventional MR arthrography for detection and characterisation of anteroinferior labroligamentous lesions, with arthroscopy as reference standard. Inter-observer variability of both protocols was determined. Institutional review board approval was obtained; informed consent was waived. MR arthrograms, including oblique axial fat suppressed T1-weighted images in ABER position and conventional imaging directions of 250 patients (170 men, 80 women; mean age, 36 years), were retrospectively and independently evaluated by three reviewers. Reviewers were blinded to clinical information and arthroscopic results. Labroligamentous lesions were registered in both ABER and MRa. The lesions were sub-classified (Bankart, Perthes, anterior labrum periosteal sleeve avulsion (ALPSA) or lesions not otherwise specified). Inter-observer agreement was assessed by Kappa statistics for all 250 patients. Ninety-two of 250 patients underwent arthroscopy. Sensitivity, specificity and accuracy of ABER versus conventional MR arthrography were calculated and compared using paired McNemar test. Kappa values of the ABER and conventional MR arthrography ranged from 0.44 to 0.56 and 0.44 to 0.62, respectively. According to arthroscopy, 45 of 92 patients had an intact anteroinferior labrum, and in 44 patients, a labroligamentous lesion (eight Bankart, seven Perthes, 29 ALPSA and three lesions not otherwise specified) was diagnosed. There were no statistically significant differences between ABER and conventional MR arthrography regarding sensitivity (85-89%, 89-96%), specificity (82-91%, 84-89%) and overall accuracy (50-62%, 53-63%). The results of a single MR arthrography series in ABER position are comparable with those of conventional MR arthrography for detecting anteroinferior labroligamentous lesions. (orig.)

  19. Application of PET-CT in monitoring residual and extrahepatic metastatic lesions for hepatocellular carcinoma with positive alpha fetoproteins after interventional therapy

    International Nuclear Information System (INIS)

    Zhu Guangyu; Teng Gaojun; Guo Jinhe; Deng Gang; He Shicheng; Fang Wen; Li Guozhao; Chen Xiaohui; Wei Xiaoying

    2010-01-01

    Objective: To investigate the value of positron emission tomography-computed tomography (PET-CT) in monitoring the residual lesions in lipiodol sedimentary region and extrahepatic metastastic lesions of hepatocellular carcinoma (HCC) with alpha fetoproteins (AFP) positive after interventional therapy. Methods: The data of 20 cases with primary HCC confirmed by histopathology were retrospectively analyzed. Their AFP levels decreased to normal range after interventional treatments, but rose to abnormal high level during following-up. After the abdominal routine imaging examinations, the definite diagnosis of the residual lesions in lipiodol sedimentary region or extrahepatic lesions can't be made confidently. All cases were scanned by PET-CT, and according to their PET-CT results, the further treatments were given and the therapeutic results were monitored with radiology and AFP tests. Results: In all 20 cases, 10 of them were detected to have the extrahepatic metastastic lesions by PET-CT, including 4 with abdominal wall metastasis upon the liver, 3 with solitary pulmonary metastasis with diameter less than 1 cm, 2 with mesenteric metastasis, 1 with metastasis of operative incisions, but these lesions were neglected by abdominal routine imaging examinations. Eight cases showed the uneven lipiodol sedimentary region in the primary lesion by CT or MRI examination, but can't be diagnosed whether it was residual lesion with other examinations including DSA. A definite diagnosis was obtained by PET-CT. In 2 cases, lymph nodes less than 1.5 cm were found in the hepatic portal area (PHA) and retroperitoneum on CT images, which was determined to be metastatic by PET-CT. All the detected lesions were given further treatments of surgery or interventional therapy. Most patients showed decreased AFP levels except the 2 patients with lymph node metastasis. The imaging examinations also indicated that the treatments had a good effect on lesions. Conclusion: In the patients with

  20. Accurate Depth of Radiofrequency-Induced Lesions in Renal Sympathetic Denervation Based on a Fine Histological Sectioning Approach in a Porcine Model.

    Science.gov (United States)

    Sakaoka, Atsushi; Terao, Hisako; Nakamura, Shintaro; Hagiwara, Hitomi; Furukawa, Toshihito; Matsumura, Kiyoshi; Sakakura, Kenichi

    2018-02-01

    Ablation lesion depth caused by radiofrequency-based renal denervation (RDN) was limited to radiofrequency-RDN cannot ablate a substantial percentage of renal sympathetic nerves. We aimed to define the true lesion depth achieved with radiofrequency-RDN using a fine sectioning method and to investigate biophysical parameters that could predict lesion depth. Radiofrequency was delivered to 87 sites in 14 renal arteries from 9 farm pigs at various ablation settings: 2, 4, 6, and 9 W for 60 seconds and 6 W for 120 seconds. Electric impedance and electrode temperature were recorded during ablation. At 7 days, 2470 histological sections were obtained from the treated arteries. Maximum lesion depth increased at 2 to 6 W, peaking at 6.53 (95% confidence interval, 4.27-8.78) mm under the 6 W/60 s condition. It was not augmented by greater power (9 W) or longer duration (120 seconds). There were statistically significant tendencies at 6 and 9 W, with higher injury scores in the media, nerves, arterioles, and fat. Maximum lesion depth was positively correlated with impedance reduction and peak electrode temperature (Pearson correlation coefficients were 0.59 and 0.53, respectively). Lesion depth was 6.5 mm for radiofrequency-RDN at 6 W/60 s. The impedance reduction and peak electrode temperature during ablation were closely associated with lesion depth. Hence, these biophysical parameters could provide prompt feedback during radiofrequency-RDN procedures in the clinical setting. © 2018 The Authors.

  1. How distributed processing produces false negatives in voxel-based lesion-deficit analyses.

    Science.gov (United States)

    Gajardo-Vidal, Andrea; Lorca-Puls, Diego L; Crinion, Jennifer T; White, Jitrachote; Seghier, Mohamed L; Leff, Alex P; Hope, Thomas M H; Ludersdorfer, Philipp; Green, David W; Bowman, Howard; Price, Cathy J

    2018-07-01

    In this study, we hypothesized that if the same deficit can be caused by damage to one or another part of a distributed neural system, then voxel-based analyses might miss critical lesion sites because preservation of each site will not be consistently associated with preserved function. The first part of our investigation used voxel-based multiple regression analyses of data from 359 right-handed stroke survivors to identify brain regions where lesion load is associated with picture naming abilities after factoring out variance related to object recognition, semantics and speech articulation so as to focus on deficits arising at the word retrieval level. A highly significant lesion-deficit relationship was identified in left temporal and frontal/premotor regions. Post-hoc analyses showed that damage to either of these sites caused the deficit of interest in less than half the affected patients (76/162 = 47%). After excluding all patients with damage to one or both of the identified regions, our second analysis revealed a new region, in the anterior part of the left putamen, which had not been previously detected because many patients had the deficit of interest after temporal or frontal damage that preserved the left putamen. The results illustrate how (i) false negative results arise when the same deficit can be caused by different lesion sites; (ii) some of the missed effects can be unveiled by adopting an iterative approach that systematically excludes patients with lesions to the areas identified in previous analyses, (iii) statistically significant voxel-based lesion-deficit mappings can be driven by a subset of patients; (iv) focal lesions to the identified regions are needed to determine whether the deficit of interest is the consequence of focal damage or much more extensive damage that includes the identified region; and, finally, (v) univariate voxel-based lesion-deficit mappings cannot, in isolation, be used to predict outcome in other patients

  2. Visualization of suspicious lesions in breast MRI based on intelligent neural systems

    Science.gov (United States)

    Twellmann, Thorsten; Lange, Oliver; Nattkemper, Tim Wilhelm; Meyer-Bäse, Anke

    2006-05-01

    Intelligent medical systems based on supervised and unsupervised artificial neural networks are applied to the automatic visualization and classification of suspicious lesions in breast MRI. These systems represent an important component of future sophisticated computer-aided diagnosis systems and enable the extraction of spatial and temporal features of dynamic MRI data stemming from patients with confirmed lesion diagnosis. By taking into account the heterogenity of the cancerous tissue, these techniques reveal the malignant, benign and normal kinetic signals and and provide a regional subclassification of pathological breast tissue. Intelligent medical systems are expected to have substantial implications in healthcare politics by contributing to the diagnosis of indeterminate breast lesions by non-invasive imaging.

  3. Characterizing stroke lesions using digital templates and lesion quantification tools in a web-based imaging informatics system for a large-scale stroke rehabilitation clinical trial

    Science.gov (United States)

    Wang, Ximing; Edwardson, Matthew; Dromerick, Alexander; Winstein, Carolee; Wang, Jing; Liu, Brent

    2015-03-01

    Previously, we presented an Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE) imaging informatics system that supports a large-scale phase III stroke rehabilitation trial. The ePR system is capable of displaying anonymized patient imaging studies and reports, and the system is accessible to multiple clinical trial sites and users across the United States via the web. However, the prior multicenter stroke rehabilitation trials lack any significant neuroimaging analysis infrastructure. In stroke related clinical trials, identification of the stroke lesion characteristics can be meaningful as recent research shows that lesion characteristics are related to stroke scale and functional recovery after stroke. To facilitate the stroke clinical trials, we hope to gain insight into specific lesion characteristics, such as vascular territory, for patients enrolled into large stroke rehabilitation trials. To enhance the system's capability for data analysis and data reporting, we have integrated new features with the system: a digital brain template display, a lesion quantification tool and a digital case report form. The digital brain templates are compiled from published vascular territory templates at each of 5 angles of incidence. These templates were updated to include territories in the brainstem using a vascular territory atlas and the Medical Image Processing, Analysis and Visualization (MIPAV) tool. The digital templates are displayed for side-by-side comparisons and transparent template overlay onto patients' images in the image viewer. The lesion quantification tool quantifies planimetric lesion area from user-defined contour. The digital case report form stores user input into a database, then displays contents in the interface to allow for reviewing, editing, and new inputs. In sum, the newly integrated system features provide the user with readily-accessible web-based tools to identify the vascular territory involved, estimate lesion area

  4. Recurrent neural networks for breast lesion classification based on DCE-MRIs

    Science.gov (United States)

    Antropova, Natasha; Huynh, Benjamin; Giger, Maryellen

    2018-02-01

    Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) plays a significant role in breast cancer screening, cancer staging, and monitoring response to therapy. Recently, deep learning methods are being rapidly incorporated in image-based breast cancer diagnosis and prognosis. However, most of the current deep learning methods make clinical decisions based on 2-dimentional (2D) or 3D images and are not well suited for temporal image data. In this study, we develop a deep learning methodology that enables integration of clinically valuable temporal components of DCE-MRIs into deep learning-based lesion classification. Our work is performed on a database of 703 DCE-MRI cases for the task of distinguishing benign and malignant lesions, and uses the area under the ROC curve (AUC) as the performance metric in conducting that task. We train a recurrent neural network, specifically a long short-term memory network (LSTM), on sequences of image features extracted from the dynamic MRI sequences. These features are extracted with VGGNet, a convolutional neural network pre-trained on a large dataset of natural images ImageNet. The features are obtained from various levels of the network, to capture low-, mid-, and high-level information about the lesion. Compared to a classification method that takes as input only images at a single time-point (yielding an AUC = 0.81 (se = 0.04)), our LSTM method improves lesion classification with an AUC of 0.85 (se = 0.03).

  5. The impact of sample size on the reproducibility of voxel-based lesion-deficit mappings.

    Science.gov (United States)

    Lorca-Puls, Diego L; Gajardo-Vidal, Andrea; White, Jitrachote; Seghier, Mohamed L; Leff, Alexander P; Green, David W; Crinion, Jenny T; Ludersdorfer, Philipp; Hope, Thomas M H; Bowman, Howard; Price, Cathy J

    2018-07-01

    This study investigated how sample size affects the reproducibility of findings from univariate voxel-based lesion-deficit analyses (e.g., voxel-based lesion-symptom mapping and voxel-based morphometry). Our effect of interest was the strength of the mapping between brain damage and speech articulation difficulties, as measured in terms of the proportion of variance explained. First, we identified a region of interest by searching on a voxel-by-voxel basis for brain areas where greater lesion load was associated with poorer speech articulation using a large sample of 360 right-handed English-speaking stroke survivors. We then randomly drew thousands of bootstrap samples from this data set that included either 30, 60, 90, 120, 180, or 360 patients. For each resample, we recorded effect size estimates and p values after conducting exactly the same lesion-deficit analysis within the previously identified region of interest and holding all procedures constant. The results show (1) how often small effect sizes in a heterogeneous population fail to be detected; (2) how effect size and its statistical significance varies with sample size; (3) how low-powered studies (due to small sample sizes) can greatly over-estimate as well as under-estimate effect sizes; and (4) how large sample sizes (N ≥ 90) can yield highly significant p values even when effect sizes are so small that they become trivial in practical terms. The implications of these findings for interpreting the results from univariate voxel-based lesion-deficit analyses are discussed. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  6. Absence of IL-1β positively affects neurological outcome, lesion development and axonal plasticity after spinal cord injury

    Directory of Open Access Journals (Sweden)

    Boato Francesco

    2013-01-01

    Full Text Available Abstract Precise crosstalk between the nervous and immune systems is important for neuroprotection and axon plasticity after injury. Recently, we demonstrated that IL-1β acts as a potent inducer of neurite outgrowth from organotypic brain slices in vitro, suggesting a potential function of IL-1β in axonal plasticity. Here, we have investigated the effects of IL-1β on axon plasticity during glial scar formation and on functional recovery in a mouse model of spinal cord compression injury (SCI. We used an IL-1β deficiency model (IL-1βKO mice and administered recombinant IL-1β. In contrast to our hypothesis, the histological analysis revealed a significantly increased lesion width and a reduced number of corticospinal tract fibers caudal to the lesion center after local application of recombinant IL-1β. Consistently, the treatment significantly worsened the neurological outcome after SCI in mice compared with PBS controls. In contrast, the absence of IL-1β in IL-1βKO mice significantly improved recovery from SCI compared with wildtype mice. Histological analysis revealed a smaller lesion size, reduced lesion width and greatly decreased astrogliosis in the white matter, while the number of corticospinal tract fibers increased significantly 5 mm caudal to the lesion in IL-1βKO mice relative to controls. Our study for the first time characterizes the detrimental effects of IL-1β not only on lesion development (in terms of size and glia activation, but also on the plasticity of central nervous system axons after injury.

  7. The brain and the subjective experience of time. A voxel based symptom-lesion mapping study.

    Science.gov (United States)

    Trojano, Luigi; Caccavale, Michelina; De Bellis, Francesco; Crisci, Claudio

    2017-06-30

    The aim of the study was to identify the anatomical bases involved in the subjective experience of time, by means of a voxel based symptom-lesion mapping (VLSM) study on patients with focal brain damage. Thirty-three patients (nineteen with right-hemisphere lesions -RBD, and fourteen with left lesion- LBD) and twenty-eight non-neurological controls (NNC) underwent the semi-structured QUEstionnaire for the Subjective experience of Time (QUEST) requiring retrospective and prospective judgements on self-relevant time intervals. All participants also completed tests to assess general cognitive functioning and two questionnaires to evaluate their emotional state. Both groups of brain-damaged patients achieved significantly different scores from NNC on the time performance, without differences between RBD and LBD. VLSM showed a cluster of voxels located in the right inferior parietal lobule significantly related to errors in the prospective items. The lesion subtraction analysis revealed two different patterns possibly associated with errors in the prospective items (the right inferior parietal cortex, rolandic operculum and posterior middle temporal gyrus) and in the retrospective items (superior middle temporal gyrus, white matter posterior to the insula). Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Fusion of classifiers for REIS-based detection of suspicious breast lesions

    Science.gov (United States)

    Lederman, Dror; Wang, Xingwei; Zheng, Bin; Sumkin, Jules H.; Tublin, Mitchell; Gur, David

    2011-03-01

    After developing a multi-probe resonance-frequency electrical impedance spectroscopy (REIS) system aimed at detecting women with breast abnormalities that may indicate a developing breast cancer, we have been conducting a prospective clinical study to explore the feasibility of applying this REIS system to classify younger women (breast cancer. The system comprises one central probe placed in contact with the nipple, and six additional probes uniformly distributed along an outside circle to be placed in contact with six points on the outer breast skin surface. In this preliminary study, we selected an initial set of 174 examinations on participants that have completed REIS examinations and have clinical status verification. Among these, 66 examinations were recommended for biopsy due to findings of a highly suspicious breast lesion ("positives"), and 108 were determined as negative during imaging based procedures ("negatives"). A set of REIS-based features, extracted using a mirror-matched approach, was computed and fed into five machine learning classifiers. A genetic algorithm was used to select an optimal subset of features for each of the five classifiers. Three fusion rules, namely sum rule, weighted sum rule and weighted median rule, were used to combine the results of the classifiers. Performance evaluation was performed using a leave-one-case-out cross-validation method. The results indicated that REIS may provide a new technology to identify younger women with higher than average risk of having or developing breast cancer. Furthermore, it was shown that fusion rule, such as a weighted median fusion rule and a weighted sum fusion rule may improve performance as compared with the highest performing single classifier.

  9. The role of rostral prefrontal cortex in prospective memory: a voxel-based lesion study.

    Science.gov (United States)

    Volle, Emmanuelle; Gonen-Yaacovi, Gil; Costello, Angela de Lacy; Gilbert, Sam J; Burgess, Paul W

    2011-07-01

    Patients with lesions in rostral prefrontal cortex (PFC) often experience problems in everyday-life situations requiring multitasking. A key cognitive component that is critical in multitasking situations is prospective memory, defined as the ability to carry out an intended action after a delay period filled with unrelated activity. The few functional imaging studies investigating prospective memory have shown consistent activation in both medial and lateral rostral PFC but also in more posterior prefrontal regions and non-frontal regions. The aim of this study was to determine regions that are necessary for prospective memory performance, using the human lesion approach. We designed an experimental paradigm allowing us to assess time-based (remembering to do something at a particular time) and event-based (remembering to do something in a particular situation) prospective memory, using two types of material, words and pictures. Time estimation tasks and tasks controlling for basic attention, inhibition and multiple instructions processing were also administered. We examined brain-behaviour relationships with a voxelwise lesion method in 45 patients with focal brain lesions and 107 control subjects using this paradigm. The results showed that lesions in the right polar prefrontal region (in Brodmann area 10) were specifically associated with a deficit in time-based prospective memory tasks for both words and pictures. This deficit could not be explained by impairments in basic attention, detection, inhibition or multiple instruction processing, and there was also no deficit in event-based prospective memory conditions. In addition to their prospective memory difficulties, these polar prefrontal patients were significantly impaired in time estimation ability compared to other patients. The same region was found to be involved using both words and pictures, suggesting that right rostral PFC plays a material nonspecific role in prospective memory. This is the first

  10. Sudden onset of sleep due to hypothalamic lesions in neuromyelitis optica spectrum disorder positive for anti-aquaporin-4 antibody.

    Science.gov (United States)

    Okuma, H; Matsumura, K; Hatanaka, Y; Saito, F; Sonoo, M

    2014-09-01

    We report a patient with neuromyelitis optica spectrum disorders who presented with sudden onset of sleep as the sole manifestation. Magnetic resonance imaging investigation revealed lesions in the hypothalamus bilaterally, which vanished completely after methylprednisolone pulse therapy. © The Author(s) 2014.

  11. Arrested pneumatization of the sphenoid sinus mimicking intraosseous lesions of the skull base

    Energy Technology Data Exchange (ETDEWEB)

    Jalali, Elnaz; Tadinada, Aditya [Dept. of Oral and Maxillofacial Radiology, University of Connecticut School of Dental Medicine, Farmington (United States)

    2015-03-15

    Arrested pneumatization of the sphenoid sinus is a developmental variant that is not always well recognized and is often confused with other pathologies associated with the skull base. This report describes the case of a patient referred for cone-beam computed tomography (CBCT) imaging for dental implant therapy. CBCT demonstrated a well-defined incidental lesion in the left sphenoid sinus with soft tissue-like density and sclerotic borders with internal curvilinear opacifications. The differential diagnoses included intraosseous lipoma, arrested pneumatization of the sphenoid sinus, chondrosarcoma, chondroid chordoma, and ossifying fibroma. The radiographic diagnosis of arrested pneumatization was based on the location of the lesion, its well-defined nature, the presence of internal opacifications, and lack of expansion. Gray-scale CBCT imaging of the area demonstrated values similar to fatty tissue. This case highlighted the fact that benign developmental variants associated with the skull base share similar radiographic features with more serious pathological entities.

  12. Natural history of chondroid skull base lesions - case report and review

    International Nuclear Information System (INIS)

    Schmidinger, A.; Rosahl, S.K.; Vorkapic, P.; Samii, M.

    2002-01-01

    Long-term follow-up reports on chondroid lesions of the skull base are rarely presented in the literature. There are virtually no data on natural growth rates of these tumors based on MRI obtained over a period of 10 years or longer. We followed a patient who has had such a lesion for more than 12 years. A non-progressive, slight abducens palsy has been the only associated symptom so far. Even though the patient was operated on for an additional intracranial arterio-venous malformation, clinical features and chromosomal testing excluded Maffucci's syndrome. The MRI follow-up in this case provides an extraordinary perspective on the natural history of chondroid skull base tumors. (orig.)

  13. Navigation studies based on the ubiquitous positioning technologies

    Science.gov (United States)

    Ye, Lei; Mi, Weijie; Wang, Defeng

    2007-11-01

    This paper summarized the nowadays positioning technologies, such as absolute positioning methods and relative positioning methods, indoor positioning and outdoor positioning, active positioning and passive positioning. Global Navigation Satellite System (GNSS) technologies were introduced as the omnipresent out-door positioning technologies, including GPS, GLONASS, Galileo and BD-1/2. After analysis of the shortcomings of GNSS, indoor positioning technologies were discussed and compared, including A-GPS, Cellular network, Infrared, Electromagnetism, Computer Vision Cognition, Embedded Pressure Sensor, Ultrasonic, RFID (Radio Frequency IDentification), Bluetooth, WLAN etc.. Then the concept and characteristics of Ubiquitous Positioning was proposed. After the ubiquitous positioning technologies contrast and selection followed by system engineering methodology, a navigation system model based on Incorporate Indoor-Outdoor Positioning Solution was proposed. And this model was simulated in the Galileo Demonstration for World Expo Shanghai project. In the conclusion, the prospects of ubiquitous positioning based navigation were shown, especially to satisfy the public location information acquiring requirement.

  14. The method for detecting small lesions in medical image based on sliding window

    Science.gov (United States)

    Han, Guilai; Jiao, Yuan

    2016-10-01

    At present, the research on computer-aided diagnosis includes the sample image segmentation, extracting visual features, generating the classification model by learning, and according to the model generated to classify and judge the inspected images. However, this method has a large scale of calculation and speed is slow. And because medical images are usually low contrast, when the traditional image segmentation method is applied to the medical image, there is a complete failure. As soon as possible to find the region of interest, improve detection speed, this topic attempts to introduce the current popular visual attention model into small lesions detection. However, Itti model is mainly for natural images. But the effect is not ideal when it is used to medical images which usually are gray images. Especially in the early stages of some cancers, the focus of a disease in the whole image is not the most significant region and sometimes is very difficult to be found. But these lesions are prominent in the local areas. This paper proposes a visual attention mechanism based on sliding window, and use sliding window to calculate the significance of a local area. Combined with the characteristics of the lesion, select the features of gray, entropy, corner and edge to generate a saliency map. Then the significant region is segmented and distinguished. This method reduces the difficulty of image segmentation, and improves the detection accuracy of small lesions, and it has great significance to early discovery, early diagnosis and treatment of cancers.

  15. Three dimensional quantitative coronary angiography can detect reliably ischemic coronary lesions based on fractional flow reserve.

    Science.gov (United States)

    Chung, Woo-Young; Choi, Byoung-Joo; Lim, Seong-Hoon; Matsuo, Yoshiki; Lennon, Ryan J; Gulati, Rajiv; Sandhu, Gurpreet S; Holmes, David R; Rihal, Charanjit S; Lerman, Amir

    2015-06-01

    Conventional coronary angiography (CAG) has limitations in evaluating lesions producing ischemia. Three dimensional quantitative coronary angiography (3D-QCA) shows reconstructed images of CAG using computer based algorithm, the Cardio-op B system (Paieon Medical, Rosh Ha'ayin, Israel). The aim of this study was to evaluate whether 3D-QCA can reliably predict ischemia assessed by myocardial fractional flow reserve (FFR) < 0.80. 3D-QCA images were reconstructed from CAG which also were evaluated with FFR to assess ischemia. Minimal luminal diameter (MLD), percent diameter stenosis (%DS), minimal luminal area (MLA), and percent area stenosis (%AS) were obtained. The results of 3D-QCA and FFR were compared. A total of 266 patients was enrolled for the present study. FFR for all lesions ranged from 0.57 to 1.00 (0.85 ± 0.09). Measurement of MLD, %DS, MLA, and %AS all were significantly correlated with FFR (r = 0.569, 0609, 0.569, 0.670, respectively, all P < 0.001). In lesions with MLA < 4.0 mm(2), %AS of more than 65.5% had a 80% sensitivity and a 83% specificity to predict FFR < 0.80 (area under curve, AUC was 0.878). 3D-QCA can reliably predict coronary lesions producing ischemia and may be used to guide therapeutic approach for coronary artery disease.

  16. Establishment of a mathematical model for the influence of respiratory movement upon the position of an intrahepatic space-occupying lesion

    International Nuclear Information System (INIS)

    Yu Yonghua; Luo Limin; Li Baosheng; Yu Jinming; Liang Chaoqian; Zhao Yuehuan

    2002-01-01

    Objective: To investigate the extent of liver lesion shifting with respiration in an attempt to establish a relevant mathematical model. Methods: We measured breathing movements with B ultrasonography in 84 primary or metastatic liver tumors and defined the relation between the lesion shifting extent with age, sex, height, weight, lesion location and size analyzed with the SPSS statistic software. Results: The Z, X and Y breathing-axis motions were 1.029±0.321 cm (range: 0.6-1.9 cm), 0.301 ± 0.131 cm (range: 0.0-0.6 cm) and 0.387±0.130 cm (range: 0.2-0.7 cm), respectively. The movement-related factor analysis revealed that age, weight and (right lobe) lesion location presented a negative relationship but height, sex and lesion size presented a positive relationship for Z, Y and X breathing-axis motions. Their mathematical regression models were established as Z = -2.660 + 2.952 H-1.539 x 10 -2 W-3.928 x 10 -3 A; Y = -0. 926 + 0. 987 H-4.992 x 10 -3 W, and X = 0.507 + 7.629 x 10 -2 S-3.686 x 10 -3 W [H : height (m), W : weight (kg) A : age (year), S : sex(M:1, F: 0)]. The liver breathing movement was verified with the model in another 11 patients and the conformation rate was up to 91%. Conclusions: The impact of breathing movement on the location of intrahepatic lesion is mainly focused on the Z-axis motion. The practical accuracy in anticipating breathing movement with the mathematical model is so justified that the use of this model be recommended in stereotactic radiotherapy

  17. Synthesis of modified oligonucleotides that contain purine and pyrimidine radio-induced base lesions

    International Nuclear Information System (INIS)

    Romieu, Anthony

    1999-01-01

    Different factors as oxidizing or carcinogenesis agents, UV and ionizing radiations,.... can generate a wide, spectrum of DNA base damages. In order to study the biochemical and structural features of these DNA damages, it is important to prepare short DNA fragments (20 to 50 bases long) bearing a single or several modifications at specific sites in their sequences. The chemical synthesis is a powerful tool to prepare such modified DNA fragments. This work focusses on the chemical incorporation of several modified nucleosides formed in DNA by ionizing radiations or by photo-sensitization. The first part of this study describes the preparation of a phosphoramidite synthon of 5-hydroxy-2'-deoxyuridine and its subsequent incorporation into synthetic oligonucleotides ranging from 14 to 33 bases long. In a second part (chapters Ill and IV), the synthesis and incorporation of original radiation-induced tandem lesions: the carbon-bridged cyclo-nucleosides are presented. Both (5'R)- and (5'S) diastereomers of 5',8-cyclo-2'-deoxyadenosine and 5',8-cyclo-2'-deoxyguanosine have been individually inserted into various different oligonucleotides (3 to 22 bases long) by using the standard phosphoramidite chemistry. The chemical incorporation of a pyrimidine analogue: (5'S, 6S)-5',6-cyclo-5,6-dihydro-thymidine has been also achieved. The loss of aromaticity of this modified nucleoside and its poor reactivity required the development of a synthetic strategy entirely different from that used for the preparation and subsequent incorporation of the phosphoramidite synthons of 5',8-cyclo-purine-2'-deoxyribo-nucleosides. The third part of this study deals with the synthesis of a phosphoramidite synthon of 4-hydroxy-8-oxo-4,8-dihydro-2'-deoxyguanosine. The two (4R)- and (4S)- diastereomers of this oxidized purine have been separated and individually inserted in several synthetic DNA fragments. No epimerization of C-4 position was observed during the solid-phase synthesis and during the

  18. Locate the Lesion: A Project-Based Learning Case that Stimulates Comprehension and Application of Neuroanatomy.

    Science.gov (United States)

    Lemons, Michele L

    2017-01-01

    A fictitious patient, Mr. Challenge, is admitted to the emergency room and displays symptoms consistent with damage to the central nervous system. In this problem-based learning case, students are challenged to determine the location of a lesion that is consistent with Mr. Challenge's symptoms. Students discover details about Mr. Challenge's symptoms while exploring three anatomical pathways: corticospinal tract, spinothalamic tract and medial lemniscal pathway. Students make predictions as to which of these pathways may be damaged in Mr. Challenge and defend their predictions based on their research of the function and anatomical location of these tracts. This ultimately leads the student to identifying a single lesion site that can account for Mr. Challenge's symptoms. This case is executed in an undergraduate neuroscience course and would be useful in anatomy and physiology course, as well as other courses that serve students interested in health science related careers.

  19. [Evidence-based therapy for cartilage lesions in the knee - regenerative treatment options].

    Science.gov (United States)

    Proffen, B; von Keudell, A; Vavken, P

    2012-06-01

    The treatment of cartilage defects has seen a shift from replacement to regeneration in the last few years. The rationale behind this development is the improvement in the quality-of-care for the growing segment of young patients who are prone to arthroplasty complications because of their specific characteristics - young age, high level of activity, high demand for functionality. These days, two of the most popular regenerative treatments are microfracture and autologous chondrocyte implantation (ACI). Although these new options show promising results, no final algorithm for the treatment of cartilage lesions has been established as yet. The objective of this review is to describe and compare these two treatment options and to present an evidence-based treatment algorithm for focal cartilage defects. Microfracture is a cost-effective, arthroscopic one-stage procedure, in which by drilling of the subchondral plate, mesenchymal stem cells from the bone marrow migrate into the defect and rebuild the cartilage. ACI is a two-stage procedure in which first chondrocytes are harvested, expanded in cell culture and in a second open procedure reimplanted into the cartilage defect. Microfracture is usually used for focal cartilage defects osteophyte, and for the ACI patient, periosteal hypertrophy and the need for two procedures in ACI. Only a few studies provide detailed and evidence-based information on a comparative assessment. These studies, however, are showing widely similar clinical outcomes but better histological results for ACI, which are likely to translate into better long-term outcomes. Although evidence-based studies comparing microfracture and ACI have not found significant differences in the clinical outcome, the literature does show that choosing the treatment based on the size and characteristics of the osteochondral lesion might be beneficial. The American Association of Orthopedic Surgeons suggest that contained lesions < 4 cm2 should be treated by

  20. Base-pairing preferences, physicochemical properties and mutational behaviour of the DNA lesion 8-nitroguanine.

    Science.gov (United States)

    Bhamra, Inder; Compagnone-Post, Patricia; O'Neil, Ian A; Iwanejko, Lesley A; Bates, Andrew D; Cosstick, Richard

    2012-11-01

    8-Nitro-2'-deoxyguanosine (8-nitrodG) is a relatively unstable, mutagenic lesion of DNA that is increasingly believed to be associated with tissue inflammation. Due to the lability of the glycosidic bond, 8-nitrodG cannot be incorporated into oligodeoxynucleotides (ODNs) by chemical DNA synthesis and thus very little is known about its physicochemical properties and base-pairing preferences. Here we describe the synthesis of 8-nitro-2'-O-methylguanosine, a ribonucleoside analogue of this lesion, which is sufficiently stable to be incorporated into ODNs. Physicochemical studies demonstrated that 8-nitro-2'-O-methylguanosine adopts a syn conformation about the glycosidic bond; thermal melting studies and molecular modelling suggest a relatively stable syn-8-nitroG·anti-G base pair. Interestingly, when this lesion analogue was placed in a primer-template system, extension of the primer by either avian myeloblastosis virus reverse transcriptase (AMV-RT) or human DNA polymerase β (pol β), was significantly impaired, but where incorporation opposite 8-nitroguanine did occur, pol β showed a 2:1 preference to insert dA over dC, while AMV-RT incorporated predominantly dC. The fact that no 8-nitroG·G base pairing is seen in the primer extension products suggests that the polymerases may discriminate against this pairing system on the basis of its poor geometric match to a Watson-Crick pair.

  1. Base-pairing preferences, physicochemical properties and mutational behaviour of the DNA lesion 8-nitroguanine†

    Science.gov (United States)

    Bhamra, Inder; Compagnone-Post, Patricia; O’Neil, Ian A.; Iwanejko, Lesley A.; Bates, Andrew D.; Cosstick, Richard

    2012-01-01

    8-Nitro-2′-deoxyguanosine (8-nitrodG) is a relatively unstable, mutagenic lesion of DNA that is increasingly believed to be associated with tissue inflammation. Due to the lability of the glycosidic bond, 8-nitrodG cannot be incorporated into oligodeoxynucleotides (ODNs) by chemical DNA synthesis and thus very little is known about its physicochemical properties and base-pairing preferences. Here we describe the synthesis of 8-nitro-2′-O-methylguanosine, a ribonucleoside analogue of this lesion, which is sufficiently stable to be incorporated into ODNs. Physicochemical studies demonstrated that 8-nitro-2′-O-methylguanosine adopts a syn conformation about the glycosidic bond; thermal melting studies and molecular modelling suggest a relatively stable syn-8-nitroG·anti-G base pair. Interestingly, when this lesion analogue was placed in a primer-template system, extension of the primer by either avian myeloblastosis virus reverse transcriptase (AMV-RT) or human DNA polymerase β (pol β), was significantly impaired, but where incorporation opposite 8-nitroguanine did occur, pol β showed a 2:1 preference to insert dA over dC, while AMV-RT incorporated predominantly dC. The fact that no 8-nitroG·G base pairing is seen in the primer extension products suggests that the polymerases may discriminate against this pairing system on the basis of its poor geometric match to a Watson–Crick pair. PMID:22965127

  2. Pigmented skin lesion detection using random forest and wavelet-based texture

    Science.gov (United States)

    Hu, Ping; Yang, Tie-jun

    2016-10-01

    The incidence of cutaneous malignant melanoma, a disease of worldwide distribution and is the deadliest form of skin cancer, has been rapidly increasing over the last few decades. Because advanced cutaneous melanoma is still incurable, early detection is an important step toward a reduction in mortality. Dermoscopy photographs are commonly used in melanoma diagnosis and can capture detailed features of a lesion. A great variability exists in the visual appearance of pigmented skin lesions. Therefore, in order to minimize the diagnostic errors that result from the difficulty and subjectivity of visual interpretation, an automatic detection approach is required. The objectives of this paper were to propose a hybrid method using random forest and Gabor wavelet transformation to accurately differentiate which part belong to lesion area and the other is not in a dermoscopy photographs and analyze segmentation accuracy. A random forest classifier consisting of a set of decision trees was used for classification. Gabor wavelets transformation are the mathematical model of visual cortical cells of mammalian brain and an image can be decomposed into multiple scales and multiple orientations by using it. The Gabor function has been recognized as a very useful tool in texture analysis, due to its optimal localization properties in both spatial and frequency domain. Texture features based on Gabor wavelets transformation are found by the Gabor filtered image. Experiment results indicate the following: (1) the proposed algorithm based on random forest outperformed the-state-of-the-art in pigmented skin lesions detection (2) and the inclusion of Gabor wavelet transformation based texture features improved segmentation accuracy significantly.

  3. Evaluation of Dixon Sequence on Hybrid PET/MR Compared with Contrast-Enhanced PET/CT for PET-Positive Lesions

    International Nuclear Information System (INIS)

    Jeong, Ju Hye; Cho, Ihn Ho; Kong, Eun Jung; Chun, Kyung Ah

    2014-01-01

    Hybrid positron emission tomography and magnetic resonance (PET/MR) imaging performs a two-point Dixon MR sequence for attenuation correction. However, MR data in hybrid PET/MR should provide anatomic and morphologic information as well as an attenuation map. We evaluated the Dixon sequence of hybrid PET/MR for anatomic correlation of PET-positive lesions compared with contrast-enhanced PET/computed tomography (CT) in patients with oncologic diseases. Twelve patients underwent a single injection, dual imaging protocol. PET/CT was performed with an intravenous contrast agent (85±13 min after 18 F-FDG injection of 403± 45 MBq) and then (125±19 min after injection) PET/MR was performed. Attenuation correction and anatomic allocation of PET were performed using contrast-enhanced CT for PET/CT and Dixon MR sequence for hybrid PET/MR. The Dixon MR sequence and contrast-enhanced CT were compared for anatomic correlation of PET-positive lesions (scoring scale ranging from 0 to 3 for visual ratings). Additionally, standardized uptake values (SUVs) for the detected lesions were assessed for quantitative comparison. Both hybrid PET/MR and contrast-enhanced PET/CT identified 55 lesions with increased FDG uptake in ten patients. In total, 28 lymph nodes, 11 bone lesions, 3 dermal nodules, 3 pleural thickening lesions, 2 thyroid nodules, 1 pancreas, 1 liver, 1 ovary, 1 uterus, 1 breast, 1 soft tissue and 2 lung lesions were present. The best performance was observed for anatomic correlation of PET findings by the contrast-enhanced CT scans (contrast-enhanced CT, 2.64± 0.70; in-phase, 1.29±1.01; opposed-phase, 1.29±1.15; water-weighted, 1.71±1.07; fat weighted, 0.56±1.03). A significant difference was observed between the scores obtained from the contrast-enhanced CT and all four coregistered Dixon MR images. Quantitative evaluation revealed a high correlation between the SUVs measured with hybrid PET/MR (SUVmean, 2.63±1.62; SUVmax, 4.30±2.88) and contrast-enhanced PET

  4. Evaluation of Dixon Sequence on Hybrid PET/MR Compared with Contrast-Enhanced PET/CT for PET-Positive Lesions

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ju Hye; Cho, Ihn Ho; Kong, Eun Jung; Chun, Kyung Ah [Yeungnam Univ. Hospital, Daegu (Korea, Republic of)

    2014-03-15

    Hybrid positron emission tomography and magnetic resonance (PET/MR) imaging performs a two-point Dixon MR sequence for attenuation correction. However, MR data in hybrid PET/MR should provide anatomic and morphologic information as well as an attenuation map. We evaluated the Dixon sequence of hybrid PET/MR for anatomic correlation of PET-positive lesions compared with contrast-enhanced PET/computed tomography (CT) in patients with oncologic diseases. Twelve patients underwent a single injection, dual imaging protocol. PET/CT was performed with an intravenous contrast agent (85±13 min after {sup 18}F-FDG injection of 403± 45 MBq) and then (125±19 min after injection) PET/MR was performed. Attenuation correction and anatomic allocation of PET were performed using contrast-enhanced CT for PET/CT and Dixon MR sequence for hybrid PET/MR. The Dixon MR sequence and contrast-enhanced CT were compared for anatomic correlation of PET-positive lesions (scoring scale ranging from 0 to 3 for visual ratings). Additionally, standardized uptake values (SUVs) for the detected lesions were assessed for quantitative comparison. Both hybrid PET/MR and contrast-enhanced PET/CT identified 55 lesions with increased FDG uptake in ten patients. In total, 28 lymph nodes, 11 bone lesions, 3 dermal nodules, 3 pleural thickening lesions, 2 thyroid nodules, 1 pancreas, 1 liver, 1 ovary, 1 uterus, 1 breast, 1 soft tissue and 2 lung lesions were present. The best performance was observed for anatomic correlation of PET findings by the contrast-enhanced CT scans (contrast-enhanced CT, 2.64± 0.70; in-phase, 1.29±1.01; opposed-phase, 1.29±1.15; water-weighted, 1.71±1.07; fat weighted, 0.56±1.03). A significant difference was observed between the scores obtained from the contrast-enhanced CT and all four coregistered Dixon MR images. Quantitative evaluation revealed a high correlation between the SUVs measured with hybrid PET/MR (SUVmean, 2.63±1.62; SUVmax, 4.30±2.88) and contrast

  5. Early detection of breast cancer mass lesions by mammogram segmentation images based on texture features

    International Nuclear Information System (INIS)

    Mahmood, F.H.

    2012-01-01

    Mammography is at present one of the available method for early detection of masses or abnormalities which is related to breast cancer.The calcifications. The challenge lies in early and accurate detection to overcome the development of breast cancer that affects more and more women throughout the world. Breast cancer is diagnosed at advanced stages with the help of the digital mammogram images. Masses appear in a mammogram as fine, granular clusters, which are often difficult to identify in a raw mammogram. The incidence of breast cancer in women has increased significantly in recent years. This paper proposes a computer aided diagnostic system for the extraction of features like mass lesions in mammograms for early detection of breast cancer. The proposed technique is based on a four-step procedure: (a) the preprocessing of the image is done, (b) regions of interest (ROI) specification, (c) supervised segmentation method includes two to stages performed using the minimum distance (M D) criterion, and (d) feature extraction based on Gray level Co-occurrence matrices GLC M for the identification of mass lesions. The method suggested for the detection of mass lesions from mammogram image segmentation and analysis was tested over several images taken from A L-llwiya Hospital in Baghdad, Iraq.The proposed technique shows better results.

  6. LGBTQ relationally based positive psychology: An inclusive and systemic framework.

    Science.gov (United States)

    Domínguez, Daniela G; Bobele, Monte; Coppock, Jacqueline; Peña, Ezequiel

    2015-05-01

    Positive psychologists have contributed to our understandings of how positive emotions and flexible cognition enhance resiliency. However, positive psychologists' research has been slow to address the relational resources and interactions that help nonheterosexual families overcome adversity. Addressing overlooked lesbian, gay, bisexual, transgender, or queer (LGBTQ) and systemic factors in positive psychology, this article draws on family resilience literature and LGBTQ literature to theorize a systemic positive psychology framework for working with nonheterosexual families. We developed the LGBTQ relationally based positive psychology framework that integrates positive psychology's strengths-based perspective with the systemic orientation of Walsh's (1996) family resilience framework along with the cultural considerations proposed by LGBTQ family literature. We theorize that the LGBTQ relationally based positive psychology framework takes into consideration the sociopolitical adversities impacting nonheterosexual families and sensitizes positive psychologists, including those working in organized care settings, to the systemic interactions of same-sex loving relationships. (c) 2015 APA, all rights reserved).

  7. Influence of free-stall base on tarsal joint lesions and hygiene in dairy cows.

    Science.gov (United States)

    Fulwider, W K; Grandin, T; Garrick, D J; Engle, T E; Lamm, W D; Dalsted, N L; Rollin, B E

    2007-07-01

    The objective was to quantify the incidence of tarsal lesions and level of hygiene by stall bed type. Cows were scored on 100 dairies from Wisconsin, Minnesota, Indiana, Iowa, and New York in the fall and winter. Thirty-eight dairies used rubber-filled mattresses (RFM), 27 had sand beds, 29 had waterbeds, and 6 used compost packs (CPk). Stocking density, stall dimensions, bedding amount, bedding frequency, and type of bedding were recorded. One pen of early-lactation multiparous cows on each dairy was scored based on injury of the tarsal joints at the lateral and medial surfaces and tuber calcis at the dorsal, lateral, and medial surfaces. A tarsal score of 1 represented hair loss, 2 was moderate, and 3 indicated severe swelling. Differences between bed types in the percentages of cows with lesions were tested with one-way ANOVA by lesion severity and incidence, with farm as the experimental unit. Cows on sand beds or waterbeds had fewer lesion scores of 1, 2, and 3 than those on RFM. The percentages of score 1 were 54.6 +/- 4.4 (RFM), 22.5 +/- 4.7 (sand), and 29.8 +/- 4.3 (waterbed), whereas the percentages of score 2 were 14.0 +/- 1.4, 2.3 +/- 1.5, and 5.0 +/- 1.4, and of score 3 were 3.0 +/- 0.4, 0.2 +/- 0.4, and 0.4 +/- 0.4. Cows on CPk had no lesions. Hygiene scores ranged from 1 to 5, with 1 being clean and 5 soiled. The percentages of hygiene score 1 were 0 (compost), 0.4 (RFM), 0.4 (sand), and 0.4 (waterbeds); those with score 2 were 79.0, 84.0 +/- 0.01, 73.2 +/- 0.01, and 80.4 +/- 0.01; with score 3 were 20.3, 15.2 +/- 0.01, 23.8 +/- 0.01, and 18.6 +/- 0.01; with score 4 were 0.8, 0.005 +/- 0.001, 0.006 +/- 0.001, and 0.025 +/- 0.003; and with score 5 was 0 for all bed types. Cows on RFM and waterbeds had improved hygiene compared with cows on sand beds. There was no difference in somatic cell count (SCC) by bed type. The percentage of cows in fourth lactation or greater on waterbeds (19.8 +/- 1.8) was greater than those on RFM (13.3 +/- 1.6) or on sand

  8. [Arthroscopic treatment of chondral lesions of the ankle joint. Evidence-based therapy].

    Science.gov (United States)

    Thomas, M; Jordan, M; Hamborg-Petersen, E

    2016-02-01

    Ankle sprains are the most relevant injuries of the lower extremities and can lead to damage to ligaments and osteochondral lesions. Up to 50 % of patients with a sprained ankle later develop a lesion of the cartilage in the ankle joint or an osteochondral lesion of the talus. This can lead to osteoarthritis of the injured ankle joint. Spontaneous healing is possible in all age groups in cases of a bone bruise in the subchondral bone but in isolated chondral injuries is only useful in pediatric patients. In many cases chondral and osteochondral injuries lead to increasing demarcation of the affected area and can result in progressive degeneration of the joint if not recognized in time. There also exist a certain number of osteochondral changes of the articular surface of the talus without any history of relevant trauma, which are collectively grouped under the term osteochondrosis dissecans. Perfusion disorders are discussed as one of many possible causes of these alterations. Nowadays, chondral and osteochondral defects can be treated earlier due to detection using very sensitive magnetic resonance imaging (MRI) and computed tomography (CT) techniques. The use of conservative treatment only has a chance of healing in pediatric patients. Conservative measures for adults should only be considered as adjuvant treatment to surgery.Based on a comprehensive analysis of the current literature, this article gives an overview and critical analysis of the current concepts for treatment of chondral and osteochondral injuries and lesions of the talus. With arthroscopic therapy curettage and microfracture of talar lesions are the predominant approaches or retrograde drilling of the defect is another option when the chondral coating is retained. Implantation of autologous chondral cells or homologous juvenile cartilage tissue is also possible with arthroscopic techniques. Osteochondral fractures (flake fracture) are usually performed as a mini-open procedure supported by

  9. Age trends in the prevalence of cervical squamous intraepithelial lesions among HIV-positive women in Cameroon: a cross-sectional study

    LENUS (Irish Health Repository)

    Atashili, Julius

    2012-10-29

    AbstractBackgroundCervical squamous intra-epithelial lesions (SIL) are more frequent in HIV-positive women overall. However the appropriate age at which to begin and end cervical cancer screening for early detection of lesions in HIV-positive women is not clear. We assessed the age-specific prevalence of any SIL and SIL requiring colposcopy in HIV-positive women in Cameroon.MethodsWe enrolled, interviewed and conducted conventional cervical cytology in 282 women, aged 19--68 years, initiating antiretroviral therapy in three clinics in Cameroon. In bivariable analyses, the crude relationship between age and the presence of lesions was assessed using locally weighted regression (LOWESS) methods. In multivariate analyses, generalized linear models with prevalence as the outcome, an identity link and a binomial distribution, were used to estimate prevalence differences. Bias analyses were conducted to assess the potential effect of inaccuracies in cytology.ResultsSIL were detected in 43.5% of the 276 women with satisfactory samples, 17.8% of whom had ASC-H\\/HSIL. On average, women aged 26 to 59 tended to have a slightly higher prevalence of any SIL than other women (Prevalence difference PD: 6.5%; 95%CI: -11.4, 24.4%). This PD was a function of CD4 count (heterogeneity test p-value =0.09): amongst patients with CD4 counts less than 200cells\\/uL, the prevalence was higher in patients aged 26--59, while there was essentially no difference amongst women with CD4 counts greater than 200 cells\\/uL. ASC-H\\/HSIL were present in women as young as 19 and as old as 62. Overall the prevalence of ASC-H\\/HSIL increased by 0.7% (95%CI: -3.8%, 5.1%) per decade increase in age.ConclusionBoth severe and less severe lesions were prevalent at all ages suggesting little utility of age-targeted screening among HIV-positive women. Nevertheless, the long-term evolution of these lesions needs to be assessed in prospective studies.

  10. Accurate radiotherapy positioning system investigation based on video

    International Nuclear Information System (INIS)

    Tao Shengxiang; Wu Yican

    2006-01-01

    This paper introduces the newest research production on patient positioning method in accurate radiotherapy brought by Accurate Radiotherapy Treating System (ARTS) research team of Institute of Plasma Physics of Chinese Academy of Sciences, such as the positioning system based on binocular vision, the position-measuring system based on contour matching and the breath gate controlling system for positioning. Their basic principle, the application occasion and the prospects are briefly depicted. (authors)

  11. The impact of FNAC in the management of salivary gland lesions: Institutional experiences leading to a risk-based classification scheme.

    Science.gov (United States)

    Rossi, Esther Diana; Wong, Lawrence Q; Bizzarro, Tommaso; Petrone, Gianluigi; Mule, Antonio; Fadda, Guido; Baloch, Zubair M

    2016-06-01

    Fine-needle aspiration cytology (FNAC) has proven its value as an essential step in the diagnosis of salivary gland lesions. Although the majority of salivary gland lesions, especially those that are common and benign, can be diagnosed with ease on FNAC, limited cellularity and morphologic lesion heterogeneity can pose diagnostic challenges and lead to false-positive and false-negative diagnoses. This study presents the institutional experience of FNAC of salivary gland lesions from 2 academic centers. A retrospective analysis was conducted on 1729 salivary gland FNAC specimens that were diagnosed over an 8-year period from January 2008 to March 2015. All samples were processed either with liquid-based cytology alone or in combination with air-dried, Diff-Quik-stained or alcohol-fixed, Papanicolaou-stained smears. Surgical excision was performed in 709 of 1749 FNACs (41%) that were diagnosed as nondiagnostic/inadequate (n = 29), benign (n = 111), neoplasm (n = 453), atypical (n = 15), suspicious for malignancy (n = 28), and malignant (n = 73). The overall concordance between cytologic and histologic diagnoses was 92.2%, with 91.8% concordance in the benign category and 89.5% concordance in cases diagnosed as suspicious for malignancy and malignant. The most frequent benign and malignant lesions were pleomorphic adenoma and squamous cell carcinoma, respectively. There were 46 false-negative and 13 false-positive results, leading to an overall specificity of 97.6% and diagnostic accuracy of 91.3%. FNAC is a reliable diagnostic modality for the diagnosis and management of salivary gland lesions based on its high specificity and diagnostic accuracy. Cancer Cytopathol 2016;124:388-96. © 2016 American Cancer Society. © 2016 American Cancer Society.

  12. A new background distribution-based active contour model for three-dimensional lesion segmentation in breast DCE-MRI

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hui; Liu, Yiping; Qiu, Tianshuang [Department of Biomedical Engineering, Dalian University of Technology, Dalian 116024 (China); Zhao, Zuowei, E-mail: liuhui@dlut.edu.cn [Second Affiliated Hospital, Dalian Medical University, Dalian 116027 (China); Zhang, Lina [Department of Radiology, First Affiliated Hospital, Dalian Medical University, Dalian 116027 (China)

    2014-08-15

    Purpose: To develop and evaluate a computerized semiautomatic segmentation method for accurate extraction of three-dimensional lesions from dynamic contrast-enhanced magnetic resonance images (DCE-MRIs) of the breast. Methods: The authors propose a new background distribution-based active contour model using level set (BDACMLS) to segment lesions in breast DCE-MRIs. The method starts with manual selection of a region of interest (ROI) that contains the entire lesion in a single slice where the lesion is enhanced. Then the lesion volume from the volume data of interest, which is captured automatically, is separated. The core idea of BDACMLS is a new signed pressure function which is based solely on the intensity distribution combined with pathophysiological basis. To compare the algorithm results, two experienced radiologists delineated all lesions jointly to obtain the ground truth. In addition, results generated by other different methods based on level set (LS) are also compared with the authors’ method. Finally, the performance of the proposed method is evaluated by several region-based metrics such as the overlap ratio. Results: Forty-two studies with 46 lesions that contain 29 benign and 17 malignant lesions are evaluated. The dataset includes various typical pathologies of the breast such as invasive ductal carcinoma, ductal carcinomain situ, scar carcinoma, phyllodes tumor, breast cysts, fibroadenoma, etc. The overlap ratio for BDACMLS with respect to manual segmentation is 79.55% ± 12.60% (mean ± s.d.). Conclusions: A new active contour model method has been developed and shown to successfully segment breast DCE-MRI three-dimensional lesions. The results from this model correspond more closely to manual segmentation, solve the weak-edge-passed problem, and improve the robustness in segmenting different lesions.

  13. The anterior interhemispheric approach: a safe and effective approach to anterior skull base lesions.

    Science.gov (United States)

    Mielke, Dorothee; Mayfrank, Lothar; Psychogios, Marios Nikos; Rohde, Veit

    2014-04-01

    Many approaches to the anterior skull base have been reported. Frequently used are the pterional, the unilateral or bilateral frontobasal, the supraorbital and the frontolateral approach. Recently, endoscopic transnasal approaches have become more popular. The benefits of each approach has to be weighted against its complications and limitations. The aim of this study was to investigate if the anterior interhemispheric approach (AIA) could be a safe and effective alternative approach to tumorous and non-tumorous lesions of the anterior skull base. We screened the operative records of all patients with an anterior skull base lesion undergoing transcranial surgery. We have used the AIA in 61 patients. These were exclusively patients with either olfactory groove meningioma (OGM) (n = 43), ethmoidal dural arteriovenous fistula (dAVF) ( n = 6) or frontobasal fractures of the anterior midline with cerebrospinal fluid (CSF) leakage ( n = 12). Patient records were evaluated concerning accessibility of the lesion, realization of surgical aims (complete tumor removal, dAVF obliteration, closure of the dural tear), and approach related complications. The use of the AIA exclusively in OGMs, ethmoidal dAVFs and midline frontobasal fractures indicated that we considered lateralized frontobasal lesions not suitable to be treated successfully. If restricted to these three pathologies, the AIA is highly effective and safe. The surgical aim (complete tumor removal, complete dAVF occlusion, no rhinorrhea) was achieved in all patients. The complication rate was 11.5 % (wound infection (n = 2; 3.2 %), contusion of the genu of the corpus callosum, subdural hygroma, epileptic seizure, anosmia and asymptomatic bleed into the tumor cavity (n = 1 each). Only the contusion of the corpus callosum was directly related to the approach (1.6 %). Olfaction, if present before surgery, was preserved in all patients, except one (1.6 %). The AIA is an effective and a safe approach

  14. Accumulation of premutagenic DNA lesions in mice defective in removal of oxidative base damage

    Science.gov (United States)

    Klungland, Arne; Rosewell, Ian; Hollenbach, Stephan; Larsen, Elisabeth; Daly, Graham; Epe, Bernd; Seeberg, Erling; Lindahl, Tomas; Barnes, Deborah E.

    1999-01-01

    DNA damage generated by oxidant byproducts of cellular metabolism has been proposed as a key factor in cancer and aging. Oxygen free radicals cause predominantly base damage in DNA, and the most frequent mutagenic base lesion is 7,8-dihydro-8-oxoguanine (8-oxoG). This altered base can pair with A as well as C residues, leading to a greatly increased frequency of spontaneous G·C→T·A transversion mutations in repair-deficient bacterial and yeast cells. Eukaryotic cells use a specific DNA glycosylase, the product of the OGG1 gene, to excise 8-oxoG from DNA. To assess the role of the mammalian enzyme in repair of DNA damage and prevention of carcinogenesis, we have generated homozygous ogg1−/− null mice. These animals are viable but accumulate abnormal levels of 8-oxoG in their genomes. Despite this increase in potentially miscoding DNA lesions, OGG1-deficient mice exhibit only a moderately, but significantly, elevated spontaneous mutation rate in nonproliferative tissues, do not develop malignancies, and show no marked pathological changes. Extracts of ogg1 null mouse tissues cannot excise the damaged base, but there is significant slow removal in vivo from proliferating cells. These findings suggest that in the absence of the DNA glycosylase, and in apparent contrast to bacterial and yeast cells, an alternative repair pathway functions to minimize the effects of an increased load of 8-oxoG in the genome and maintain a low endogenous mutation frequency. PMID:10557315

  15. Vascular risk factors, atherosclerosis, cerebral white matter lesions and cerebral perfusion in a population-based study

    International Nuclear Information System (INIS)

    Claus, J.J.; Breteler, M.M.B.; Hasan, D.; Krenning, E.P.; Bots, M.L.; Grobbee, D.E.; Swieten, J.C. van; Harskamp, F. van; Hofman, A.

    1996-01-01

    We studied risk factors for cerebral vascular disease (blood pressure and hypertension, factor VIIc, factor VIIIc, fibrinogen), indicators of atherosclerosis (intima-media thickness and plaques in the carotid artery) and cerebral white matter lesions in relation to regional cerebral blood flow (rCBF) in 60 persons (aged 65-85 years) recruited from a population-based study. rCBF was assessed with single-photon emission tomography using technetium-99m d,l-hexamethylpropylene amine oxime ( 99m Tc-HMPAO). Statistical analysis was performed with multiple linear regression with adjustment for age, sex and ventricle-to-brain ratio. A significant positive association was found between systolic and diastolic blood pressure and temporo-parietal rCBF. In analysis with quartiles of the distribution, we found a threshold effect for the relation of low diastolic blood pressure (≤60 mmHg) and low temporo-parietal rCBF. Levels of plasma fibrinogen were inversely related to parietal rCBF, with a threshold effect of high fibrinogen levels (>3.2 g/l) and low rCBF. Increased atherosclerosis was related to low rCBF in all cortical regions, but these associations were not significant. No consistent relation was observed between severity of cerebral white matter lesions and rCBF. Our results may have implications for blood pressure control in the elderly population. (orig.)

  16. Spectral embedding based active contour (SEAC): application to breast lesion segmentation on DCE-MRI

    Science.gov (United States)

    Agner, Shannon C.; Xu, Jun; Rosen, Mark; Karthigeyan, Sudha; Englander, Sarah; Madabhushi, Anant

    2011-03-01

    Spectral embedding (SE), a graph-based manifold learning method, has previously been shown to be useful in high dimensional data classification. In this work, we present a novel SE based active contour (SEAC) segmentation scheme and demonstrate its applications in lesion segmentation on breast dynamic contrast enhance magnetic resonance imaging (DCE-MRI). In this work, we employ SE on DCE-MRI on a per voxel basis to embed the high dimensional time series intensity vector into a reduced dimensional space, where the reduced embedding space is characterized by the principal eigenvectors. The orthogonal eigenvector-based data representation allows for computation of strong tensor gradients in the spectrally embedded space and also yields improved region statistics that serve as optimal stopping criteria for SEAC. We demonstrate both analytically and empirically that the tensor gradients in the spectrally embedded space are stronger than the corresponding gradients in the original grayscale intensity space. On a total of 50 breast DCE-MRI studies, SEAC yielded a mean absolute difference (MAD) of 3.2+/-2.1 pixels and mean Dice similarity coefficient (DSC) of 0.74+/-0.13 compared to manual ground truth segmentation. An active contour in conjunction with fuzzy c-means (FCM+AC), a commonly used segmentation method for breast DCE-MRI, produced a corresponding MAD of 7.2+/-7.4 pixels and mean DSC of 0.58+/-0.32. In conjunction with a set of 6 quantitative morphological features automatically extracted from the SEAC derived lesion boundary, a support vector machine (SVM) classifier yielded an area under the curve (AUC) of 0.73, for discriminating between 10 benign and 30 malignant lesions; the corresponding SVM classifier with the FCM+AC derived morphological features yielded an AUC of 0.65.

  17. Base-pairing preferences, physicochemical properties and mutational behaviour of the DNA lesion 8-nitroguanine †

    OpenAIRE

    Bhamra, Inder; Compagnone-Post, Patricia; O’Neil, Ian A.; Iwanejko, Lesley A.; Bates, Andrew D.; Cosstick, Richard

    2012-01-01

    8-Nitro-2′-deoxyguanosine (8-nitrodG) is a relatively unstable, mutagenic lesion of DNA that is increasingly believed to be associated with tissue inflammation. Due to the lability of the glycosidic bond, 8-nitrodG cannot be incorporated into oligodeoxynucleotides (ODNs) by chemical DNA synthesis and thus very little is known about its physicochemical properties and base-pairing preferences. Here we describe the synthesis of 8-nitro-2′-O-methylguanosine, a ribonucleoside analogue of this lesi...

  18. Incidence of chronic knee lesions in long-distance runners based on training level: Findings at MRI

    International Nuclear Information System (INIS)

    Schueller-Weidekamm, Claudia; Schueller, Gerd; Uffmann, Martin; Bader, Till

    2006-01-01

    Purpose: The purpose of this study was to evaluate the incidence of chronic knee changes in long-distance runners based on the training status, including distance, running frequency, training pace, and running experience. Methods: MRI of the knee was performed in 26 non-professional runners 5 days after their last training unit. Lesions of the menisci and cartilage (5-point scale), bone marrow and ligaments (3-point scale), and joint effusion were evaluated. A total score comprising all knee lesions in each runner was evaluated. The incidence of the knee changes was correlated with the training level, gender, and age of the runners. Results: Grade 1 lesions of the menisci were found in six runners with a high training level, and in only four runners with a low training level. Grade 1 cartilage lesions were found in three high-trained runners and in one low-trained runner, and grade 2 lesions were found in one high-trained runner and in two low-trained runners, respectively. Grade 1 anterior cruciate ligament lesions were seen in three runners with a high- and in two runners with a low-training level. Runners with a higher training level showed a statistically significant higher score for all chronic knee lesions than those with a lower training level (p < 0.05). Conclusions: MRI findings indicate that a higher training level in long-distance runners is a risk factor for chronic knee lesions

  19. Incidence of chronic knee lesions in long-distance runners based on training level: Findings at MRI

    Energy Technology Data Exchange (ETDEWEB)

    Schueller-Weidekamm, Claudia [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)]. E-mail: claudia.schueller-weidekamm@meduniwien.ac.at; Schueller, Gerd [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Uffmann, Martin [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Bader, Till [Department of Radiology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2006-05-15

    Purpose: The purpose of this study was to evaluate the incidence of chronic knee changes in long-distance runners based on the training status, including distance, running frequency, training pace, and running experience. Methods: MRI of the knee was performed in 26 non-professional runners 5 days after their last training unit. Lesions of the menisci and cartilage (5-point scale), bone marrow and ligaments (3-point scale), and joint effusion were evaluated. A total score comprising all knee lesions in each runner was evaluated. The incidence of the knee changes was correlated with the training level, gender, and age of the runners. Results: Grade 1 lesions of the menisci were found in six runners with a high training level, and in only four runners with a low training level. Grade 1 cartilage lesions were found in three high-trained runners and in one low-trained runner, and grade 2 lesions were found in one high-trained runner and in two low-trained runners, respectively. Grade 1 anterior cruciate ligament lesions were seen in three runners with a high- and in two runners with a low-training level. Runners with a higher training level showed a statistically significant higher score for all chronic knee lesions than those with a lower training level (p < 0.05). Conclusions: MRI findings indicate that a higher training level in long-distance runners is a risk factor for chronic knee lesions.

  20. Proportion of false-positive lesions at interim and end-of-treatment FDG-PET in lymphoma as determined by histology: Systematic review and meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Hugo J.A., E-mail: h.j.a.adams@gmail.com; Kwee, Thomas C.

    2016-11-15

    Purpose: To systematically review and meta-analyze the proportion of false-positive lesions at interim and end-of-treatment {sup 18}F-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) in lymphoma using biopsy as reference standard. Materials and methods: Medline was searched for original studies. Methodological quality of included studies was evaluated, and results were meta-analytically summarized using random effects (in case of interstudy heterogeneity [I{sup 2} ≤ 50%]) or fixed effects (in case of no interstudy heterogeneity [I{sup 2} > 50%]). Results: Eleven studies, comprising 139 patients who underwent biopsy of an FDG-avid lesion during or after completion of antilymphoma treatment, were included. Overall methodological quality was moderate. The proportion of false-positive results among all biopsied FDG-avid lesions at PET performed during of after completion of treatment ranged between 7.7% and 90.5% (the vast majority was due to inflammatory changes), with a weighted summary proportion (random effects, I{sup 2} = 75.7%) of 55.7% (95% confidence interval [CI]: 32.6–76.6%). There were no available studies on interim FDG-PET in Hodgkin lymphoma. The pooled summary false-positive proportions were 83.0% (95% CI: 72.0%–90.2%) for interim FDG-PET in non-Hodgkin lymphoma (fixed effects, I{sup 2} = 27.7%), 23.1% (95% CI: 4.7%–64.5%) for end-of-treatment FDG-PET in Hodgkin lymphoma (random effects; I{sup 2} = 67.1%), and 31.5% (95% CI: 3.9%–83.9%) for end-of-treatment FDG-PET in non-Hodgkin lymphoma (random effects, I{sup 2} = 68.3%). Conclusion: Both interim and end-of-treatment FDG-PET scans in patients with lymphoma suffer from a very high number of false-positive FDG-avid lesions. This finding, in combination with the previously reported high number of false-negative FGD-PET scans for residual disease detection, suggests that the role of interim and end-of-treatment FDG-PET should be reconsidered.

  1. Performance of visual inspection with acetic acid and human papillomavirus testing for detection of high-grade cervical lesions in HIV positive and HIV negative Tanzanian women

    DEFF Research Database (Denmark)

    Dartell, Myassa Arkam; Rasch, Vibeke; Iftner, Thomas

    2014-01-01

    The aim of this cross sectional study was to assess type distribution of human papillomavirus (HPV) among HIV positive and HIV negative women who underwent cervical cancer screening, and to examine the ability of visual inspection with acetic acid (VIA), the standard detection method in Tanzania......, and HPV-testing to detect cytologically diagnosed high grade lesions or cancer (HSIL+). Women from different areas in Tanzania were invited by public announcement to cervical cancer screening organized by Ocean Road Cancer Institute (Dar-es-Salaam). A total of 3,767 women were enrolled. Women underwent...

  2. Application of a data-mining method based on Bayesian networks to lesion-deficit analysis

    Science.gov (United States)

    Herskovits, Edward H.; Gerring, Joan P.

    2003-01-01

    Although lesion-deficit analysis (LDA) has provided extensive information about structure-function associations in the human brain, LDA has suffered from the difficulties inherent to the analysis of spatial data, i.e., there are many more variables than subjects, and data may be difficult to model using standard distributions, such as the normal distribution. We herein describe a Bayesian method for LDA; this method is based on data-mining techniques that employ Bayesian networks to represent structure-function associations. These methods are computationally tractable, and can represent complex, nonlinear structure-function associations. When applied to the evaluation of data obtained from a study of the psychiatric sequelae of traumatic brain injury in children, this method generates a Bayesian network that demonstrates complex, nonlinear associations among lesions in the left caudate, right globus pallidus, right side of the corpus callosum, right caudate, and left thalamus, and subsequent development of attention-deficit hyperactivity disorder, confirming and extending our previous statistical analysis of these data. Furthermore, analysis of simulated data indicates that methods based on Bayesian networks may be more sensitive and specific for detecting associations among categorical variables than methods based on chi-square and Fisher exact statistics.

  3. Descriptions of spinal MRI lesions and definition of a positive MRI of the spine in axial spondyloarthritis

    DEFF Research Database (Denmark)

    Hermann, Kay-Geert A; Baraliakos, Xenofon; van der Heijde, Désirée M F M

    2012-01-01

    The aim of this study was to define characteristic MRI findings in the spine of patients with axial spondyloarthritis (SpA) and provide a definition of a positive spinal MRI for inflammation and structural changes.......The aim of this study was to define characteristic MRI findings in the spine of patients with axial spondyloarthritis (SpA) and provide a definition of a positive spinal MRI for inflammation and structural changes....

  4. Base Pair Opening in a Deoxynucleotide Duplex Containing a cis-syn Thymine Cyclobutane Dimer Lesion

    Science.gov (United States)

    Wenke, Belinda B.; Huiting, Leah N.; Frankel, Elisa B.; Lane, Benjamin F.; Núñez, Megan E.

    2014-01-01

    The cis-syn thymine cyclobutane dimer is a DNA photoproduct implicated in skin cancer. We compared the stability of individual base pairs in thymine dimer-containing duplexes to undamaged parent 10-mer duplexes. UV melting thermodynamic measurements, CD spectroscopy, and 2D NOESY NMR spectroscopy confirm that the thymine dimer lesion is locally and moderately destabilizing within an overall B-form duplex conformation. We measured the rates of exchange of individual imino protons by NMR using magnetization transfer from water and determined the equilibrium constant for the opening of each base pair Kop. In the normal duplex Kop decreases from the frayed ends of the duplex toward the center, such that the central TA pair is the most stable with a Kop of 8×10−7. In contrast, base pair opening at the 5’T of the thymine dimer is facile. The 5’T of the dimer has the largest equilibrium constant (Kop =3×10−4) in its duplex, considerably larger than even the frayed penultimate base pairs. Notably, base pairing by the 3’T of the dimer is much more stable than by the 5’T, indicating that the predominant opening mechanism for the thymine dimer lesion is not likely to be flipping out into solution as a single unit. The dimer asymmetrically affects the stability of the duplex in its vicinity, destabilizing base pairing on its 5’ side more than on the 3’ side. The striking differences in base pair opening between parent and dimer duplexes occur independently of the duplex-single strand melting transitions. PMID:24328089

  5. Focal retrograde amnesia: voxel-based morphometry findings in a case without MRI lesions.

    Directory of Open Access Journals (Sweden)

    Bernhard Sehm

    Full Text Available Focal retrograde amnesia (FRA is a rare neurocognitive disorder presenting with an isolated loss of retrograde memory. In the absence of detectable brain lesions, a differentiation of FRA from psychogenic causes is difficult. Here we report a case study of persisting FRA after an epileptic seizure. A thorough neuropsychological assessment confirmed severe retrograde memory deficits while anterograde memory abilities were completely normal. Neurological and psychiatric examination were unremarkable and high-resolution MRI showed no neuroradiologically apparent lesion. However, voxel-based morphometry (VBM-comparing the MRI to an education-, age-and sex-matched control group (n = 20 disclosed distinct gray matter decreases in left temporopolar cortex and a region between right posterior parahippocampal and lingual cortex. Although the results of VBM-based comparisons between a single case and a healthy control group are generally susceptible to differences unrelated to the specific symptoms of the case, we believe that our data suggest a causal role of the cortical areas detected since the retrograde memory deficit is the preeminent neuropsychological difference between patient and controls. This was paralleled by grey matter differences in central nodes of the retrograde memory network. We therefore suggest that these subtle alterations represent structural correlates of the focal retrograde amnesia in our patient. Beyond the implications for the diagnosis and etiology of FRA, our results advocate the use of VBM in conditions that do not show abnormalities in clinical radiological assessment, but show distinct neuropsychological deficits.

  6. Impact of Lesion Placement on Efficacy and Safety of Catheter-Based Radiofrequency Renal Denervation.

    Science.gov (United States)

    Mahfoud, Felix; Tunev, Stefan; Ewen, Sebastian; Cremers, Bodo; Ruwart, Jennifer; Schulz-Jander, Daniel; Linz, Dominik; Davies, Justin; Kandzari, David E; Whitbourn, Robert; Böhm, Michael; Melder, Robert J

    2015-10-20

    Insufficient procedural efficacy has been proposed to explain nonresponse to renal denervation (RDN). The aim of this study was to examine the impact of different patterns of lesion placements on the efficacy and consistency of catheter-based radiofrequency RDN in pigs. The impact of increasing number of lesions versus location of RDN was investigated in a porcine model (Group 1; n = 51). The effect of treating the main artery, the branches, and the 2 combined was compared in Group 2 (n = 48). The durability of response and safety of combined treatment of the main artery plus branches was examined in Group 3 (n = 16). Renal norepinephrine (NE) tissue content and renal cortical axon density were assessed. Increasing the number of RF lesions (4, 8, and 12) in the main renal artery was not sufficient to yield a clear dose-response relationship on NE content and axon density. In contrast, targeted treatment of the renal artery branches or distal segment of the main renal artery resulted in markedly less variability of response and significantly greater reduction of both NE and axon density than conventional treatment of only the main renal artery. Combination treatment (main artery plus branches) produced the greatest change in renal NE and axon density with the least heterogeneity. The changes were durable through 28 days post-treatment. These data provide the rationale for investigation of an optimized approach for RDN in future clinical studies. This may have profound implications for the clinical application of RDN, as this approach may not only achieve greater reductions in sympathetic activity but also reduce treatment effect variability. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  7. Simulation on Temperature Field of Radiofrequency Lesions System Based on Finite Element Method

    International Nuclear Information System (INIS)

    Xiao, D; Qian, Z; Li, W; Qian, L

    2011-01-01

    This paper mainly describes the way to get the volume model of damaged region according to the simulation on temperature field of radiofrequency ablation lesion system in curing Parkinson's disease based on finite element method. This volume model reflects, to some degree, the shape and size of the damaged tissue during the treatment with all tendencies in different time or core temperature. By using Pennes equation as heat conduction equation of radiofrequency ablation of biological tissue, the author obtains the temperature distribution field of biological tissue in the method of finite element for solving equations. In order to establish damage models at temperature points of 60 deg. C, 65 deg. C, 70 deg. C, 75 deg. C, 80 deg. C, 85 deg. C and 90 deg. C while the time points are 30s, 60s, 90s and 120s, Parkinson's disease model of nuclei is reduced to uniform, infinite model with RF pin at the origin. Theoretical simulations of these models are displayed, focusing on a variety of conditions about the effective lesion size on horizontal and vertical. The results show the binary complete quadratic non-linear joint temperature-time models of the maximum damage diameter and maximum height. The models can comprehensively reflect the degeneration of target tissue caused by radio frequency temperature and duration. This lay the foundation for accurately monitor of clinical RF treatment of Parkinson's disease in the future.

  8. Histogram-based quantitative evaluation of endobronchial ultrasonography images of peripheral pulmonary lesion.

    Science.gov (United States)

    Morikawa, Kei; Kurimoto, Noriaki; Inoue, Takeo; Mineshita, Masamichi; Miyazawa, Teruomi

    2015-01-01

    Endobronchial ultrasonography using a guide sheath (EBUS-GS) is an increasingly common bronchoscopic technique, but currently, no methods have been established to quantitatively evaluate EBUS images of peripheral pulmonary lesions. The purpose of this study was to evaluate whether histogram data collected from EBUS-GS images can contribute to the diagnosis of lung cancer. Histogram-based analyses focusing on the brightness of EBUS images were retrospectively conducted: 60 patients (38 lung cancer; 22 inflammatory diseases), with clear EBUS images were included. For each patient, a 400-pixel region of interest was selected, typically located at a 3- to 5-mm radius from the probe, from recorded EBUS images during bronchoscopy. Histogram height, width, height/width ratio, standard deviation, kurtosis and skewness were investigated as diagnostic indicators. Median histogram height, width, height/width ratio and standard deviation were significantly different between lung cancer and benign lesions (all p histogram standard deviation. Histogram standard deviation appears to be the most useful characteristic for diagnosing lung cancer using EBUS images. © 2015 S. Karger AG, Basel.

  9. OD Matrix Acquisition Based on Mobile Phone Positioning Data

    Directory of Open Access Journals (Sweden)

    Xiaoqing ZUO

    2014-06-01

    Full Text Available Dynamic OD matrix is basic data of traffic travel guidance, traffic control, traffic management and traffic planning, and reflects the basic needs of travelers on the traffic network. With the rising popularity of positioning technology and the communication technology and the generation of huge mobile phone users, the mining and use of mobile phone positioning data, can get more traffic intersections and import and export data. These data will be integrated into obtaining the regional OD matrix, which is bound to bring convenience. In this article, mobile phone positioning data used in the data acquisition of intelligent transportation system, research a kind of regional dynamic OD matrix acquisition method based on the mobile phone positioning data. The method based on purpose of transportation, using time series similarity classification algorithm based on piecewise linear representation of the corner point (CP-PLR, mapping each base station cell to traffic zone of different traffic characteristics, and through a series of mapping optimization of base station cell to traffic zone to realize city traffic zone division based on mobile phone traffic data, on the basis, adjacency matrix chosen as the physical data structure of OD matrix storage, the principle of obtaining regional dynamic OD matrix based on the mobile phone positioning data are expounded, and the algorithm of obtaining regional dynamic OD matrix based on mobile phone positioning data are designed and verified.

  10. Schiff Base Metal Derivatives Enhance the Expression of HSP70 and Suppress BAX Proteins in Prevention of Acute Gastric Lesion

    Directory of Open Access Journals (Sweden)

    Shahram Golbabapour

    2013-01-01

    Full Text Available Schiff base complexes have appeared to be promising in the treatment of different diseases and disorders and have drawn a lot of attention to their biological activities. This study was conducted to evaluate the regulatory effect of Schiff base metal derivatives on the expression of heat shock proteins (HSP 70 and BAX in protection against acute haemorrhagic gastric ulcer in rats. Rats were assigned to 6 groups of 6 rats: the normal control (Tween 20 5% v/v, 5 mL/kg, the positive control (Tween 20 5% v/v, 5 mL/kg, and four Schiff base derivative groups named Schiff_1, Schiff_2, Schiff_3, and Schiff_4 (25 mg/kg. After 1 h, all of the groups received ethanol 95% (5 mL/kg but the normal control received Tween 20 (Tween 20 5% v/v, 5 mL/kg. The animals were euthanized after 60 min and the stomachs were dissected for histology (H&E, immunohistochemistry, and western blot analysis against HSP70 and BAX proteins. The results showed that the Schiff base metal derivatives enhanced the expression of HSP70 and suppressed the expression of BAX proteins during their gastroprotection against ethanol-induced gastric lesion in rats.

  11. Schiff base metal derivatives enhance the expression of HSP70 and suppress BAX proteins in prevention of acute gastric lesion.

    Science.gov (United States)

    Golbabapour, Shahram; Gwaram, Nura Suleiman; Al-Obaidi, Mazen M Jamil; Soleimani, A F; Ali, Hapipah Mohd; Abdul Majid, Nazia

    2013-01-01

    Schiff base complexes have appeared to be promising in the treatment of different diseases and disorders and have drawn a lot of attention to their biological activities. This study was conducted to evaluate the regulatory effect of Schiff base metal derivatives on the expression of heat shock proteins (HSP) 70 and BAX in protection against acute haemorrhagic gastric ulcer in rats. Rats were assigned to 6 groups of 6 rats: the normal control (Tween 20 5% v/v, 5 mL/kg), the positive control (Tween 20 5% v/v, 5 mL/kg), and four Schiff base derivative groups named Schiff_1, Schiff_2, Schiff_3, and Schiff_4 (25 mg/kg). After 1 h, all of the groups received ethanol 95% (5 mL/kg) but the normal control received Tween 20 (Tween 20 5% v/v, 5 mL/kg). The animals were euthanized after 60 min and the stomachs were dissected for histology (H&E), immunohistochemistry, and western blot analysis against HSP70 and BAX proteins. The results showed that the Schiff base metal derivatives enhanced the expression of HSP70 and suppressed the expression of BAX proteins during their gastroprotection against ethanol-induced gastric lesion in rats.

  12. Improved spring model-based collaborative indoor visible light positioning

    Science.gov (United States)

    Luo, Zhijie; Zhang, WeiNan; Zhou, GuoFu

    2016-06-01

    Gaining accuracy with indoor positioning of individuals is important as many location-based services rely on the user's current position to provide them with useful services. Many researchers have studied indoor positioning techniques based on WiFi and Bluetooth. However, they have disadvantages such as low accuracy or high cost. In this paper, we propose an indoor positioning system in which visible light radiated from light-emitting diodes is used to locate the position of receivers. Compared with existing methods using light-emitting diode light, we present a high-precision and simple implementation collaborative indoor visible light positioning system based on an improved spring model. We first estimate coordinate position information using the visible light positioning system, and then use the spring model to correct positioning errors. The system can be employed easily because it does not require additional sensors and the occlusion problem of visible light would be alleviated. We also describe simulation experiments, which confirm the feasibility of our proposed method.

  13. Quantitative study of neurofilament-positive fiber length in rat spinal cord lesions using isotropic virtual planes

    DEFF Research Database (Denmark)

    von Euler, Mia; Larsen, Jytte Overgaard; Janson, A M

    1998-01-01

    analysis after spinal cord injury is needed. Length quantification of the putatively spontaneously regenerating fibers has been difficult until recently, when two length estimators based on sampling with isotropic virtual planes within thick physical sections were introduced. The applicability...

  14. There is less MRI brain lesions and no characteristic MRI Brain findings in IIDDs patients with positive AQP4 serology among Malaysians.

    Science.gov (United States)

    Abdullah, Suhailah; Fadzli, Farhana; Ramli, Norlisah; Tan, Chong Tin

    2017-02-01

    The recently introduced International Consensus diagnostic criteria for diagnosis of neuromyelitis spectrum disorder include patients who are seronegative for AQP4 antibody. The criteria are dependent on typical MRI changes in the spinal cord, optic nerve and brain. This study aims to determine whether there are significant differences in the MRI brain images between AQP4 positive and negative patients with IIDDs. MRI brain of patients with a diagnosis of IIDDs presented to the Hospital from 2010 to 2015 was analysed. The MRI was assessed by 2 radiologists blinded to the AQP4 status, on features said to be typical of NMOSD and MS. Thirty nine patients fulfilled the criteria and were included in the study. They consisted of 19 AQP4 seropositive and 20 AQP4 seronegative patients. The mean age was older (37.0 vs. 28.8 years) among the AQP4 positive group. The majority of the patients were ethnic Chinese (72%), followed by the Malays and Indians. Those with AQP4 seropositive status generally has less brain lesions, and significantly less fulfilling the McDonald DIS criteria as compared to those with AQP4 seronegative status (15.8% vs. 60.0%, p=0.005). None of the seven cerebral MRI features highlighted in NMOSD 2015 diagnostic criteria, said to be characteristic of NMOSD was more common among the AQP4 positive patients. These features were in fact seen less frequently among the AQP4 seropositive patients. An example was the extensive hemispheric lesion seen in 10.5% of AQP4 seropositive patients vs. 45% of that AQP4 seronegative group. There was no characteristic MRI brain features in the Malaysian AQP4 seropositive IIDD patients versus those who are seronegative. This could be a reflection of ethnical difference. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Secretory leukocyte protease inhibitor expression and high-risk HPV infection in anal lesions of HIV positive patients

    Science.gov (United States)

    NUOVO, Gerard J.; GRINSZTEJN, Beatriz; FRIEDMAN, Ruth K.; VELOSO, Valdiléa G.; CUNHA, Cynthia B.; COUTINHO, José R.; VIANNA-ANDRADE, Cecilia; OLIVEIRA, Nathalia S.; WOODHAM, Andrew W.; DA SILVA, Diane M.; KAST, W. Martin

    2016-01-01

    Objective The aim of the current study was to evaluate secretory leukocyte protease inhibitor (SLPI) expression in anal biopsies from HIV-positive (HIV+) individuals, and compare that to anal intraepithelial neoplasia (AIN) diagnoses and human papillomavirus (HPV) status. Design This is a cross-sectional study of a cohort of 54 HIV+ (31 males and 23 females) from an AIDS clinic in Rio de Janeiro, Brazil. Methods The study material consisted of anorectal tissue biopsies obtained from HIV+ subjects, which were used to construct tissue microarray paraffin blocks for immunohistochemical analysis of SLPI expression. Biopsies were evaluated by an expert pathologist and classified as low-grade anal intraepithelial neoplasia (AIN1), high-grade anal intraepithelial neoplasia (AIN2/3), or normal squamous epithelium. Additionally, DNA from the biopsies was extracted and analyzed for the presence of low- or high-risk HPV DNA. Results Histologically normal squamous epithelium from the anorectal region showed strong positive SLPI staining in 17/20 (85%) samples. In comparison, 9/17 (53%) dysplastic squamous epithelial samples from AIN1 patients showed strong SLPI staining, and only 5/17 (29%) samples from AIN2-3 patients exhibited strong SPLI staining, which both were significantly fewer than those from normal tissue (p=0.005). Furthermore, there was a significantly higher proportion of samples in which oncogenic high-risk HPV genotypes were detected in low SLPI expressing tissues than that in tissues with high SLPI expression (p=0.040). Conclusion Taken together these results suggest that low SLPI expression is associated with high-risk HPV infections in the development of AIN. PMID:27149102

  16. An object-based approach for detecting small brain lesions: application to Virchow-Robin spaces.

    Science.gov (United States)

    Descombes, Xavier; Kruggel, Frithjof; Wollny, Gert; Gertz, Hermann Josef

    2004-02-01

    This paper is concerned with the detection of multiple small brain lesions from magnetic resonance imaging (MRI) data. A model based on the marked point process framework is designed to detect Virchow-Robin spaces (VRSs). These tubular shaped spaces are due to retraction of the brain parenchyma from its supplying arteries. VRS are described by simple geometrical objects that are introduced as small tubular structures. Their radiometric properties are embedded in a data term. A prior model includes interactions describing the clustering property of VRS. A Reversible Jump Markov Chain Monte Carlo algorithm (RJMCMC) optimizes the proposed model, obtained by multiplying the prior and the data model. Example results are shown on T1-weighted MRI datasets of elderly subjects.

  17. Fundamental study of the radiation monitoring system based on evaluation of DNA lesions

    International Nuclear Information System (INIS)

    Shimizu, K.; Matuo, Y.; Izumi, Y.; Ikeda, T.

    2011-01-01

    The biological dosemeter that measures biological responses to ionising radiation is useful for radiation protection. This paper presents the development and characterisation of a gamma ray irradiation dosimetry system based on real-time PCR (polymerase chain reaction) methodology. Real-time PCR is used to amplify and simultaneously quantify a targeted DNA molecule. If there are no limitations due to limiting substrates or reagents, at each extension step, the amount of DNA target is doubled, leading to exponential (geometric) amplification of the specific DNA fragment. The essential point of this assay is that DNA lesions caused by ionising radiation block DNA synthesis by DNA polymerase, resulting in a decrease in the amplification of a damaged DNA template compared with that of non-damaged DNA templates. (authors)

  18. [Psychotherapy of patients with brain lesions: an integrative model based on neuropsychological and psychodynamic perspectives].

    Science.gov (United States)

    Ouss-Ryngaert, Lisa

    2010-12-01

    Our model of psychotherapy for patients with brain lesions is based on an integrative approach of psychobehavioral symptoms, especially from the neuropsychological and psychodynamic perspectives. Adjustment of technical modalities and aims of psychoanalytical therapy is required for these patients. The analysis of the influence of cognitive disorders on transference and contre-transference plays a major role, including the role of procedural processes in changes in the intersubjective relationship between the patient and the therapist. Two vignettes are presented to illustrate our model, which respects the integrity of the cognitive and psychodynamic approaches and can be implemented by only one therapist, using alternatively each lecture, or by a working team bringing to light the different aspects of the same symptom.

  19. Global positioning method based on polarized light compass system

    Science.gov (United States)

    Liu, Jun; Yang, Jiangtao; Wang, Yubo; Tang, Jun; Shen, Chong

    2018-05-01

    This paper presents a global positioning method based on a polarized light compass system. A main limitation of polarization positioning is the environment such as weak and locally destroyed polarization environments, and the solution to the positioning problem is given in this paper which is polarization image de-noising and segmentation. Therefore, the pulse coupled neural network is employed for enhancing positioning performance. The prominent advantages of the present positioning technique are as follows: (i) compared to the existing position method based on polarized light, better sun tracking accuracy can be achieved and (ii) the robustness and accuracy of positioning under weak and locally destroyed polarization environments, such as cloudy or building shielding, are improved significantly. Finally, some field experiments are given to demonstrate the effectiveness and applicability of the proposed global positioning technique. The experiments have shown that our proposed method outperforms the conventional polarization positioning method, the real time longitude and latitude with accuracy up to 0.0461° and 0.0911°, respectively.

  20. Ultrasound-guided versus computed tomography-scan guided biopsy of pleural-based lung lesions.

    Science.gov (United States)

    Khosla, Rahul; McLean, Anna W; Smith, Jessica A

    2016-01-01

    Computed tomography (CT) guided biopsies have long been the standard technique to obtain tissue from the thoracic cavity and is traditionally performed by interventional radiologists. Ultrasound (US) guided biopsy of pleural-based lesions, performed by pulmonologists is gaining popularity and has the advantage of multi-planar imaging, real-time technique, and the absence of radiation exposure to patients. In this study, we aim to determine the diagnostic accuracy, the time to diagnosis after the initial consult placement, and the complications rates between the two different modalities. A retrospective study of electronic medical records was done of patients who underwent CT-guided biopsies and US-guided biopsies for pleural-based lesions between 2005 and 2014 and the data collected were analyzed for comparing the two groups. A total of 158 patients underwent 162 procedures during the study period. 86 patients underwent 89 procedures in the US group, and 72 patients underwent 73 procedures in the CT group. The overall yield in the US group was 82/89 (92.1%) versus 67/73 (91.8%) in the CT group (P = 1.0). Average days to the procedure was 7.2 versus 17.5 (P = 0.00001) in the US and CT group, respectively. Complication rate was higher in CT group 17/73 (23.3%) versus 1/89 (1.1%) in the US group (P guided biopsy is similar to that of CT-guided biopsy, with a lower complication rate and a significantly reduced time to the procedure.

  1. Location Fingerprint Extraction for Magnetic Field Magnitude Based Indoor Positioning

    Directory of Open Access Journals (Sweden)

    Wenhua Shao

    2016-01-01

    Full Text Available Smartphone based indoor positioning has greatly helped people in finding their positions in complex and unfamiliar buildings. One popular positioning method is by utilizing indoor magnetic field, because this feature is stable and infrastructure-free. In this method, the magnetometer embedded on the smartphone measures indoor magnetic field and queries its position. However, the environments of the magnetometer are rather harsh. This harshness mainly consists of coarse-grained hard/soft-iron calibrations and sensor electronic noise. The two kinds of interferences decrease the position distinguishability of the magnetic field. Therefore, it is important to extract location features from magnetic fields to reduce these interferences. This paper analyzes the main interference sources of the magnetometer embedded on the smartphone. In addition, we present a feature distinguishability measurement technique to evaluate the performance of different feature extraction methods. Experiments revealed that selected fingerprints will improve position distinguishability.

  2. High prevalence and incidence of HPV-related anal cancer precursor lesions in HIV-positive women in the late HAART era.

    Science.gov (United States)

    Hidalgo-Tenorio, Carmen; de Jesus, Samantha E; Esquivias, Javier; Pasquau, Juan

    2017-12-02

    Anal cancer is one of the most common non-AIDS defining malignancies, especially in men who have sex with men and women living with HIV (WLHIV). To evaluate the prevalence and incidence of precursor lesions (high-grade squamous intraepithelial lesions [HSIL]) and anal cancer in our cohort of women and to compare them to cervical lesions; to calculate the percentage of patients that acquire and clear oncogenic genotypes (HR-HPV) in the anal canal; and to determine predictive factors for anal HPV infection. Prospective-longitudinal study (May 2012-December 2016). At baseline (V1) and follow up visits, anal mucosa samples were taken in liquid medium for cytology and HPV PCR. In cases of abnormal anal cytology and/or positive HR-HPV PCR results, a high resolution anoscopy was performed. Patients were also referred to the gynaecologist. Ninety five women with an average age of 43.7years were included. At baseline, 11.6% had cervical abnormalities (4.1% CIN1, 2.2% CIN2/3, 1.1% cervical cancer), 64.3% anal abnormalities (50% LSIL/AIN1, 9.5% HSIL/AIN2/3 and 2.4% anal cancer) and 49.4% had HR-HPV genotypes. During 36months of follow up, the incidence of anal HSIL was 16×1,000 person-years; 14.8% acquired HR-HPV genotypes and 51.2% cleared them, P=.007. No patients presented CIN1/2/3/ or cervical cancer. In the multivariate analysis we found the following predictive factors for HR-HPV infection: smoking (RR: 1.55, 95%CI: 0.99-2.42), number of sexual partners >3 (RR: 1.69; 95%CI: 1.09-2.62), cervical and anal dysplasia (RR: 1.83; 95%CI: 1.26-2.67) and (RR: 1.55; 95%CI: 1.021-2.35), respectively. Despite clearance rates of anal oncogenic genotypes being higher than acquisition rates, prevalence and incidence of HSIL were still high and greater than cervical HSIL. Therefore, screening for these lesions should perhaps be offered to all WLHIV. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights

  3. An ICA-based method for the segmentation of pigmented skin lesions in macroscopic images.

    Science.gov (United States)

    Cavalcanti, Pablo G; Scharcanski, Jacob; Di Persia, Leandro E; Milone, Diego H

    2011-01-01

    Segmentation is an important step in computer-aided diagnostic systems for pigmented skin lesions, since that a good definition of the lesion area and its boundary at the image is very important to distinguish benign from malignant cases. In this paper a new skin lesion segmentation method is proposed. This method uses Independent Component Analysis to locate skin lesions in the image, and this location information is further refined by a Level-set segmentation method. Our method was evaluated in 141 images and achieved an average segmentation error of 16.55%, lower than the results for comparable state-of-the-art methods proposed in literature.

  4. Imaging spectrum and pitfalls of {sup 11}C-methionine position emission tomography in a series of patients with intracranial lesions

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Kimiteru [Dept. of Radiology, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo (Japan); Matsuda, Hiroshi [Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo (Japan); Kubota, Kazoo [Div. of Nuclear Medicine, National Center for Global Health and Medicine, Tokyo (Japan)

    2016-06-15

    {sup 11}C-methionine (Met) positron emission tomography (PET) is one of the most commonly used PET tracers for evaluating brain tumors. However, few reports have described tips and pitfalls of {sup 11}C-Met PET for general practitioners. Physiological {sup 11}C-Met uptake, anatomical variations, vascular disorders, non-tumorous lesions such as inflammation or dysplasia, benign brain tumors and patient condition during {sup 11}C-Met PET examination can potentially affect the image interpretation and cause false positives and negatives. These pitfalls in the interpretation of {sup 11}C-Met PET images are important for not only nuclear medicine physicians but also general radiologists. Familiarity with the spectrum and pitfalls of {sup 11}C-Met images could help prevent unfavorable clinical results caused by misdiagnoses.

  5. Comparison of Two Base Materials Regarding Their Effect on Root Canal Treatment Success in Primary Molars with Furcation Lesions

    Directory of Open Access Journals (Sweden)

    Volkan Arikan

    2016-01-01

    Full Text Available Introduction. The aim of this study was to compare MTA with another base material, IRM, which is generally used on pulpal floor after root canal treatment, regarding their effect on the success of root canal treatment of primary teeth with furcation lesions. Materials and Methods. Fifty primary teeth with furcation lesions were divided into 2 groups. Following root canal treatment, the pulpal floor was coated with MTA in the experimental group and with IRM in the control group. Teeth were followed up considering clinical (pain, pathological mobility, tenderness to percussion and palpation, and any soft tissue pathology and sinus tract and radiographical (pathological root resorption, reduced size or healing of existing lesion, and absence of new lesions at the interradicular or periapical area criteria for 18 months. For the statistical analysis, Fisher’s exact test and Pearson’s chi-square tests were used and a p value of <0.05 was considered to be statistically significant. Results. Although there were no statistically significant differences between two groups in terms of treatment success, lesions healed significantly faster in the MTA group. Conclusion. In primary teeth with furcation lesions, usage of MTA on the pulpal floor following root canal treatment can be a better alternative since it induced faster healing.

  6. 99m Tc-MIP-1404-SPECT/CT for the detection of PSMA-positive lesions in 225 patients with biochemical recurrence of prostate cancer.

    Science.gov (United States)

    Schmidkonz, Christian; Hollweg, Claudia; Beck, Michael; Reinfelder, Julia; Goetz, Theresa I; Sanders, James C; Schmidt, Daniela; Prante, Olaf; Bäuerle, Tobias; Cavallaro, Alexander; Uder, Michael; Wullich, Bernd; Goebell, Peter; Kuwert, Torsten; Ritt, Philipp

    2018-01-01

    99m Tc-MIP-1404 (Progenics Pharmaceuticals, Inc., New York, NY) is a novel, SPECT-compatible 99m Tc-labeled PSMA inhibitor for the detection of prostate cancer. We present results of its clinical use in a cohort of 225 men with histologically confirmed prostate cancer referred for workup of biochemical relapse. From April 2013 to April 2017, 99m Tc-MIP1404-scintigraphy was performed in 225 patients for workup of PSA biochemical relapse of prostate cancer. Whole-body planar and SPECT/CT images of the lower abdomen and thorax were obtained 3-4 h p.i. of 710 ± 64 MBq 99m Tc-MIP-1404. Images were visually analyzed for presence and location of abnormal uptake. In addition, quantitative analysis of the SPECT/CT data was carried out on a subset of 125 patients. Follow-up reports of subsequent therapeutic interventions were available for 59% (139) of all patients. Tracer-positive lesions were detected in 77% (174/225) of all patients. Detections occurred at the area of local recurrence in the prostate in 25% of patients (or a total of 56), with metastases in lymph nodes in 47% (105), bone in 27% (60), lung in 5% (12), and other locations in 2% (4) of patients. Detection rates were 90% at PSA levels ≥2 ng/mL and 54% below that threshold. Lesional SUVmax values were, on average, 32.2 ± 29.6 (0.8-142.2), and tumor-to-normal ratios 146.6 ± 160.5 (1.9-1482.4). The PSA level correlated significantly with total uptake of MIP-1404 in tumors (P Tc-MIP-1404-imaging and other information, an interdisciplinary tumor board review recommended changes to treatment plans in 74% (104/139) of those patients for whom the necessary documentation was available. SPECT/CT with 99m Tc-labeled MIP-1404 has a high probability in detecting PSMA-positive lesions in patients with elevated PSA. Statistical analysis disclosed significant relationship between quantitative 99m Tc-MIP-1404 uptake, PSA level, and Gleason score. © 2017 Wiley Periodicals, Inc.

  7. Managing Carious Lesions

    DEFF Research Database (Denmark)

    Schwendicke, F; Frencken, J E; Bjørndal, L

    2016-01-01

    should be prioritized, while in shallow or moderately deep lesions, restoration longevity becomes more important. For teeth with shallow or moderately deep cavitated lesions, carious tissue removal is performed according toselective removal to firm dentine.In deep cavitated lesions in primary......The International Caries Consensus Collaboration undertook a consensus process and here presents clinical recommendations for carious tissue removal and managing cavitated carious lesions, including restoration, based on texture of demineralized dentine. Dentists should manage the disease dental...

  8. Clinical evaluation of false-positive scintigraphic lesions of the left lobe in portal hypertension. Comparison with portographic findings of the pars umbilicus of the portal vein

    Energy Technology Data Exchange (ETDEWEB)

    Takayasu, Kenichi; Moriyama, Noriyuki; Suzuki, Masao; Yamada, Tatsuya [National Cancer Center, Tokyo (Japan). Hospital; Fukutake, Toshio

    1982-09-01

    sup(99m)Tc-phytate liver scan and percutaneous transhepatic portography (PTP) were performed in 33 patients with portal hypertension due to various hepatic diseases. A defect or space occupying lesion in the left lobe on the scan in these patients was analysed with reference to portographic changes of the pars umbilicus of the left portal vein and the following results were obtained. 1) A false-positive defect on the scintigram was found in 6 (18.2%) of 33 patients, and portal vein pressure (PVP) was above 200 mmH/sub 2/O in all 6 which constituted 21.4% of 28 with PVP above 200 mmH/sub 2/O. 2) In five out of 6 patients with false-positive scan findings, the pars umbilicus was dilated to more than 25 x 15 mm in size, and it was huge and tortuous in 3 of them. 3) The mean PVP in the group with a false-positive scan tended to be higher than that in patients with no abnormalities on the scintigram. It was concluded that in reading of liver scintigrams in patients with portal hypertension, a dilated pars umbilicus and huge para-umbilical vein should be considered.

  9. Determinants of cerebral white matter lesions: A longitudinal population based MRI study

    NARCIS (Netherlands)

    H.F. de Leeuw (Frank)

    1999-01-01

    textabstractW hite matter lesions are frequently found on cerebral magnetic resonance imaging scans of elderly non-demented and demented people. l-4 The pathogenesis of white matter lesions is largely unknown. However age and high diastolic and systolic blood pressure levels and indicators of

  10. Classification of the supraspinatus lesions based on the correlation between MRI and surgical findings

    International Nuclear Information System (INIS)

    Capiel, Carlos A. h; Sammartino, Mario R.; Bouzas, Carlos A.; Mussini, Daniel

    2001-01-01

    Objective: The purpose of this study was to evaluate the sensitivity of MR in the diagnosis of supraspinatus disorders and to report a classification based on the correlation between MR and surgical findings. Materials and methods: Thirty-nine patients with clinical suspected rotator cuff abnormalities were examined with MR. Two radiologists interpreted the images without knowledge of the surgical findings. MR findings were correlated with surgical ones. The classification used divides the supraspinatus disorders in two groups: a) With tendinous continuity (tendinosis and partial cuff tear); and b) Interruption of the tendinous continuity (full-thickness tear). Full thickness tears can be with severe or small retraction. Results: All the patients had full-thickness tear. MR correctly diagnosed thirty-eight tears with a sensitivity of 97,4%. Twelve tears showed small retraction and twenty-seven a severe retraction. Five patients had irreparable lesions. Conclusion: MR is an excellent method in the diagnosis of rotator cuff disorders. The classification based on the correlation between MR and surgical findings supplies an accurate diagnosis and gives an integrated scope of supraspinatus disorders. In this way the orthopaedic surgeons can define if the disorders can be clinically or surgically treated, and in this case, determine the type of surgery required (open surgery or arthroscopy). (author)

  11. Nucleotide Excision Repair Lesion-Recognition Protein Rad4 Captures a Pre-Flipped Partner Base in a Benzo[a]pyrene-Derived DNA Lesion: How Structure Impacts the Binding Pathway.

    Science.gov (United States)

    Mu, Hong; Geacintov, Nicholas E; Min, Jung-Hyun; Zhang, Yingkai; Broyde, Suse

    2017-06-19

    The xeroderma pigmentosum C protein complex (XPC) recognizes a variety of environmentally induced DNA lesions and is the key in initiating their repair by the nucleotide excision repair (NER) pathway. When bound to a lesion, XPC flips two nucleotide pairs that include the lesion out of the DNA duplex, yielding a productively bound complex that can lead to successful lesion excision. Interestingly, the efficiencies of NER vary greatly among different lesions, influencing their toxicity and mutagenicity in cells. Though differences in XPC binding may influence NER efficiency, it is not understood whether XPC utilizes different mechanisms to achieve productive binding with different lesions. Here, we investigated the well-repaired 10R-(+)-cis-anti-benzo[a]pyrene-N 2 -dG (cis-B[a]P-dG) DNA adduct in a duplex containing normal partner C opposite the lesion. This adduct is derived from the environmental pro-carcinogen benzo[a]pyrene and is likely to be encountered by NER in the cell. We have extensively investigated its binding to the yeast XPC orthologue, Rad4, using umbrella sampling with restrained molecular dynamics simulations and free energy calculations. The NMR solution structure of this lesion in duplex DNA has shown that the dC complementary to the adducted dG is flipped out of the DNA duplex in the absence of XPC. However, it is not known whether the "pre-flipped" base would play a role in its recognition by XPC. Our results show that Rad4 first captures the displaced dC, which is followed by a tightly coupled lesion-extruding pathway for productive binding. This binding path differs significantly from the one deduced for the small cis-syn cyclobutane pyrimidine dimer lesion opposite mismatched thymines [ Mu , H. , ( 2015 ) Biochemistry , 54 ( 34 ), 5263 - 7 ]. The possibility of multiple paths that lead to productive binding to XPC is consistent with the versatile lesion recognition by XPC that is required for successful NER.

  12. Characterization of oral precancerous lesions based on higher-harmonic generation microscopy

    Science.gov (United States)

    Lin, Chen-Yu; Lin, Chih-Feng; Sun, Chi-Kuang

    2013-03-01

    It is generally accepted that oral cancer arises in the presence of oral precancerous lesions. However, the clinical courses of these lesions are quite unpredictable, and a fundamental enigma remains that when and how these lesions turn to malignant growth. Characterization of these potentially malignant lesions is thus important and could serve as early indicators of this neoplastic transformation process, potentially facilitates the treatment outcome and improves the survival rate. Higher harmonic generation microscope (HGM), providing images with a leaving photodamages in the tissues, was used for this purpose. Oral cavity biopsies were obtained from 18 patients with clinical suspected oral precancerous lesions scheduled for surgical biopsy. HGM images were compared with histological images to determine the results. By visualization of subtle cellular and morphological changes, the preliminary result of this HGM image discloses excellent consistency with traditional histolopathology studies, without the need for fixation, sectioning and staining. More specifically speaking, the keratin thickness was found to be increased comparing with normal adjacent controls. In some cases, variations in cell size, nuclear size and increased nuclear/cytoplasmic ratio, and increased size of nucleoli were identified, indicating different stages of malignant transformation. These results together indicated that HGM provides the capability to characterize features of oral precancerous lesions as well as oral cancer progression, and holds the greatest potential as an ideal tool for clinical screening and surveillance of suspicious oral lesions.

  13. Prevailence of Patch Test Positivity with Some Bases

    Directory of Open Access Journals (Sweden)

    J S Pasricha

    1987-01-01

    Full Text Available To evaluate the suitability of some chemicals to act as bases for antigens for patch tests, patch tests were performed with these agents in patients having contact dermatitis. Propylene glycol′used as such produced positive reactions in 25 (50% patients of which 12 were 2 + or more, polyethylene glycol 200 produced positive reactions in 9 (18% cases of which 4 cases were 2 + or more, a mixture of liquid paraffin and hard paraffin gave rise to positive reactions in 10 (10% cases 3 of these being 2 +, a mixture of liquid paraffin and bees wax was positive in 14 (14,Yo cases 3 of these being 2 +, yellow petrolatum was positive in 4 (8% cases, one of which was 2 +, white petrolatum was positive in S (6% cases all of these being + reactions only, and glycerol gave rise to a I + reaction in only one (2% caw. In tropical countries, water should be as base for as many antigens as possible for others, a control test with the b must be included.

  14. Communication-based positioning systems: past, present and prospects

    International Nuclear Information System (INIS)

    Ma Guanyi; Wan Qingtao; Gan Tong

    2012-01-01

    This paper reviews positioning systems in the context of communication systems. First, the basic positioning technique is described for location based service (LBS) in mobile communication systems. Then the high integrity global positioning system (iGPS) is introduced in terms of aspects of what it is and how the low Earth orbit (LEO) Iridium telecommunication satellites enhance the global positioning system (GPS). Emphasis is on the Chinese Area Positioning System (CAPS) which is mainly based on commercial geostationary (GEO) communication satellites, including decommissioned GEO and inclined geosynchronous communication satellites. Characterized by its low cost, high flexibility, wide-area coverage and ample frequency resources, a distinctive feature of CAPS is that its navigation messages are generated on the ground, then uploaded to and forwarded by the communication satellites. Fundamental principles and key technologies applied in the construction of CAPS are presented in detail from the CAPS validation phase to its experimental system setup. A prospective view of CAPS has concluded it to be a seamless, high accuracy, large capacity navigation and communication system which can be achieved by expanding it world wide and enhancing it with LEO satellites and mobile base stations. Hence, this system is a potential candidate for the next generation of radio navigation after GPS. (invited reviews)

  15. Forward and correctional OFDM-based visible light positioning

    Science.gov (United States)

    Li, Wei; Huang, Zhitong; Zhao, Runmei; He, Peixuan; Ji, Yuefeng

    2017-09-01

    Visible light positioning (VLP) has attracted much attention in both academic and industrial areas due to the extensive deployment of light-emitting diodes (LEDs) as next-generation green lighting. Generally, the coverage of a single LED lamp is limited, so LED arrays are always utilized to achieve uniform illumination within the large-scale indoor environment. However, in such dense LED deployment scenario, the superposition of the light signals becomes an important challenge for accurate VLP. To solve this problem, we propose a forward and correctional orthogonal frequency division multiplexing (OFDM)-based VLP (FCO-VLP) scheme with low complexity in generating and processing of signals. In the first forward procedure of FCO-VLP, an initial position is obtained by the trilateration method based on OFDM-subcarriers. The positioning accuracy will be further improved in the second correctional procedure based on the database of reference points. As demonstrated in our experiments, our approach yields an improved average positioning error of 4.65 cm and an enhanced positioning accuracy by 24.2% compared with trilateration method.

  16. Impact of a new respiratory amplitude-based gating technique in evaluation of upper abdominal PET lesions

    Energy Technology Data Exchange (ETDEWEB)

    Van Der Gucht, Axel, E-mail: axel.vandergucht@gmail.com [Department of Nuclear Medicine, Centre Hospitalier Princesse Grace, Monaco (Monaco); Serrano, Benjamin [Department of Medical Physics, Centre Hospitalier Princesse Grace, Monaco (Monaco); Hugonnet, Florent; Paulmier, Benoît [Department of Nuclear Medicine, Centre Hospitalier Princesse Grace, Monaco (Monaco); Garnier, Nicolas [Department of Medical Physics, Centre Hospitalier Princesse Grace, Monaco (Monaco); Faraggi, Marc [Department of Nuclear Medicine, Centre Hospitalier Princesse Grace, Monaco (Monaco)

    2014-03-15

    PET acquisition requires several minutes which can lead to respiratory motion blurring, to increase partial volume effect and SUV under-estimation. To avoid these artifacts, conventional 10-min phase-based respiratory gating (PBRG) can be performed but is time-consuming and difficult with a non-compliant patient. We evaluated an automatic amplitude-based gating method (AABG) which keeps 35% of the counts at the end of expiration to minimize respiratory motion. We estimated the impact of AABG on upper abdominal lesion detectability, quantification and patient management. Methods: We consecutively included 31 patients (82 hepatic and 25 perihepatic known lesions). Each patient underwent 3 acquisitions on a Siemens Biograph mCT (4 rings and time-of-flight): a standard free-breathing whole-body (SWB, 5–7 steps/2.5 min per step, 3.3 ± 0.4 MBq/kg of 18F-FDG), a 10-min PBRG with six bins and a 5-min AABG method. All gated acquisitions were performed with an ANZAI respiratory gating system. SUV{sub max} and target to background ratio (TBR, defined as the maximum SUV of the lesion divided by the mean SUV of a region of interest drawn in healthy liver) were compared. Results: All 94 lesions in SWB images were detected in the gated images. 10-min PBRG and 5-min AABG acquisitions respectively revealed 9 and 13 new lesions and relocated 7 and 8 lesions. Four lesions revealed by 5-min AABG were missed by 10-min PBRG in 3 non-compliant patients. Both gated methods failed to relocate 2 lesions seen on SWB acquisition. Compared to SWB, TBR increased significantly with 10-min PBRG and with 5-min AABG (respectively 41 ± 59%, p = 4.10–3 and 66 ± 75%, p = 6.10–5) whereas SUV{sub max} did not (respectively 14 ± 43%, p = 0.29 with 10-min PBRG, and 24 ± 46%, p = 0.11 with 5-min AABG). Conclusion: The AABG is a fast and a user-friendly respiratory gating method to increase detectability and quantification of upper abdominal lesions compared to the conventional PBRG procedure and

  17. Study of genital lesions

    Directory of Open Access Journals (Sweden)

    Anand Kumar B

    2003-03-01

    Full Text Available A total of one hundred patients (75 males and 25 females age ranged from 17-65 years with genital lesions attending the STD clinic of Bowring and LC Hospitals Bangalore constituted the study group. Based on clinical features, the study groups were classified as syphilis (39, chancroid (30, herpes genitolis (13, condylomato lato (9, LGV (7t condylomata acuminata (5, genital scabies (3, granuloma inguinole (2 and genital candidiasis (1. In 68% microbiological findings confirmed the clinical diagnosis. Of the 100 cases 13% and 2% were positive for HIV antibodies and HbsAg respectively.

  18. Position-based quantum cryptography and catalytic computation

    NARCIS (Netherlands)

    Speelman, F.

    2016-01-01

    In this thesis, we present several results along two different lines of research. The first part concerns the study of position-based quantum cryptography, a topic in quantum cryptography. By combining quantum mechanics with special relativity theory, new cryptographic tasks can be developed that

  19. Particle based 3D modeling of positive streamer inception

    NARCIS (Netherlands)

    H.J. Teunissen (Jannis)

    2012-01-01

    htmlabstractIn this report we present a particle based 3D model for the study of streamer inception near positive electrodes in air. The particle code is of the PIC-MCC type and an electrode is included using the charge simulation method. An algorithm for the adaptive creation of super-particles is

  20. Analysis of Financial Position Based on the Balance Sheet

    OpenAIRE

    Spineanu-Georgescu Luciana

    2011-01-01

    Analysis of financial position based on the balance sheet is mainly aimed at assessing the extent to which financial structure chosen by the firm, namely, financial resources, covering the needs reflected in the balance sheet financed. This is done through an analysis known as horizontal analysis balance sheet financial imbalances.

  1. An image based system to automatically and objectivelly score the degreeof redness and scaling in psoriasi lesions

    DEFF Research Database (Denmark)

    Gomez, David Delgado; Ersbøll, Bjarne Kjær; Carstensen, Jens Michael

    2004-01-01

    In this work, a combined statistical and image analysis method to automatically evaluate the severity of scaling in psoriasis lesions is proposed. The method separates the different regions of the disease in the image and scores the degree of scaling based on the properties of these areas. The pr...... that the obtained scores are highly correlated with scores made by doctors. This and the fact that the obtained measures are continuous indicate the proposed method is a suitable tool to evaluate the lesion and to track the evolution of dermatological diseases....

  2. Incidence of symptomatic osteochondritis dissecans lesions of the knee : A population-based study in Olmsted County

    NARCIS (Netherlands)

    Pareek, A.; Sanders, T. L.; Wu, I. T.; Larson, D. R.; Saris, D. B.F.; Krych, A.J.

    2017-01-01

    Objective: To (1) define population-based incidence of knee Osteochondritis dissecans (OCD) lesions using the population of Olmsted County, (2) examine trends over time, and (3) evaluate rate of surgical management over time. Method: Study population included 302 individuals who were diagnosed with

  3. An improved strategy for skin lesion detection and classification using uniform segmentation and feature selection based approach.

    Science.gov (United States)

    Nasir, Muhammad; Attique Khan, Muhammad; Sharif, Muhammad; Lali, Ikram Ullah; Saba, Tanzila; Iqbal, Tassawar

    2018-02-21

    Melanoma is the deadliest type of skin cancer with highest mortality rate. However, the annihilation in early stage implies a high survival rate therefore, it demands early diagnosis. The accustomed diagnosis methods are costly and cumbersome due to the involvement of experienced experts as well as the requirements for highly equipped environment. The recent advancements in computerized solutions for these diagnoses are highly promising with improved accuracy and efficiency. In this article, we proposed a method for the classification of melanoma and benign skin lesions. Our approach integrates preprocessing, lesion segmentation, features extraction, features selection, and classification. Preprocessing is executed in the context of hair removal by DullRazor, whereas lesion texture and color information are utilized to enhance the lesion contrast. In lesion segmentation, a hybrid technique has been implemented and results are fused using additive law of probability. Serial based method is applied subsequently that extracts and fuses the traits such as color, texture, and HOG (shape). The fused features are selected afterwards by implementing a novel Boltzman Entropy method. Finally, the selected features are classified by Support Vector Machine. The proposed method is evaluated on publically available data set PH2. Our approach has provided promising results of sensitivity 97.7%, specificity 96.7%, accuracy 97.5%, and F-score 97.5%, which are significantly better than the results of existing methods available on the same data set. The proposed method detects and classifies melanoma significantly good as compared to existing methods. © 2018 Wiley Periodicals, Inc.

  4. Voxel-based lesion analysis of brain regions underlying reading and writing.

    Science.gov (United States)

    Baldo, Juliana V; Kacinik, Natalie; Ludy, Carl; Paulraj, Selvi; Moncrief, Amber; Piai, Vitória; Curran, Brian; Turken, And; Herron, Tim; Dronkers, Nina F

    2018-03-20

    The neural basis of reading and writing has been a source of inquiry as well as controversy in the neuroscience literature. Reading has been associated with both left posterior ventral temporal zones (termed the "visual word form area") as well as more dorsal zones, primarily in left parietal cortex. Writing has also been associated with left parietal cortex, as well as left sensorimotor cortex and prefrontal regions. Typically, the neural basis of reading and writing are examined in separate studies and/or rely on single case studies exhibiting specific deficits. Functional neuroimaging studies of reading and writing typically identify a large number of activated regions but do not necessarily identify the core, critical hubs. Last, due to constraints on the functional imaging environment, many previous studies have been limited to measuring the brain activity associated with single-word reading and writing, rather than sentence-level processing. In the current study, the brain correlates of reading and writing at both the single- and sentence-level were studied in a large sample of 111 individuals with a history of chronic stroke using voxel-based lesion symptom mapping (VLSM). VLSM provides a whole-brain, voxel-by-voxel statistical analysis of the role of distinct regions in a particular behavior by comparing performance of individuals with and without a lesion at every voxel. Rather than comparing individual cases or small groups with particular behavioral dissociations in reading and writing, VLSM allowed us to analyze data from a large, well-characterized sample of stroke patients exhibiting a wide range of reading and writing impairments. The VLSM analyses revealed that reading was associated with a critical left inferior temporo-occipital focus, while writing was primarily associated with the left supramarginal gyrus. Separate VLSM analyses of single-word versus sentence-level reading showed that sentence-level reading was uniquely associated with anterior

  5. Object-action dissociation: A voxel-based lesion-symptom mapping study on 102 patients after glioma removal

    Directory of Open Access Journals (Sweden)

    Alberto Pisoni

    Full Text Available Data concerning the neural basis of noun and verb processing are inconsistent. Some authors assume that action-verb processing is based on frontal areas while nouns processing relies on temporal regions; others argue that the circuits processing verbs and nouns are closely interconnected in a predominantly left-lateralized fronto-temporal-parietal network; yet, other researchers consider that the primary motor cortex plays a crucial role in processing action verbs. In the present study, one hundred and two patients with a tumour either in the right or left hemisphere were submitted to picture naming of objects and actions before and after surgery. To test the effect of specific brain regions in object and action naming, patients' lesions were mapped and voxel-lesion-symptom mapping (VLSM was computed. Behavioural results showed that left-brain damaged patients were significantly more impaired than right brain-damaged patients. The VLSM showed that these two grammatical classes are segregated in the left hemisphere. In particular, scores in naming of objects correlated with damage to the anterior temporal region, while scores in naming of actions correlated with lesions in the parietal areas and in the posterior temporal cortex. In addition, VLSM analyses carried out on non-linguistic tasks were not significant, confirming that the regions associated with deficits in object and action naming were not generally engaged in all cognitive tasks. Finally, the involvement of subcortical pathways was investigated and the inferior longitudinal fasciculus proved to play a role in object naming, while no specific bundle was identified for actions. Keywords: Object action dissociation, Temporal lesion, Frontal lesion, Voxel-based lesion symptom mapping

  6. Blood-Based Biomarkers for Lung Cancer Early Detection and Evaluation of CT-Based Lesions

    Science.gov (United States)

    2013-12-01

    conserved protein in eukaryotic nuclei, binds to NuMA. J Biol Chem 2000;275: 31979–85. 45. Debernardi S, Bassini A, Jones LK, Chaplin T, Linder B, de Bruijn...level and two-hit gene dosage and/or DNA methylation alterations and (ii) undergoing concomitant alterations at the mRNA level would be indicative of...methylated in our cohort ( indicated in Supplementary Table S2). Of these, we focused on the putative TSG EYA4, based on the high frequency of

  7. LESIONS OF THE MANDIBLE - A PATTERN BASED APPROACH TO DIAGNOSIS BY OPG

    Directory of Open Access Journals (Sweden)

    Anil Govind

    2015-12-01

    Full Text Available The present study of 95 orthopentograms focused on importance of OPG as a first line of investigation in the diagnosis of mandibular lesions and establish its role beyond doubt in some the conditions due to its pathognomonic appearance. It also narrows down the list of differential diagnosis. INTRODUCTION Mandibular lesions cause a variety of problems ranging from swelling, tooth mobility, displacement of adjacent teeth, mild sensitivity, root deformation of developing permanent teeth and potential to expand the bone causing fractures. Some of these mandibular lesions are silent in their progression and pose a challenge in early diagnosis for clinicians. Radiographic characteristics such as location, margin, density, relation to tooth, along with clinical notes is the first step in interpreting mandibular pathologies. Orthopentogram is a simple, accurate and cost effective technique commonly employed for diagnosing dental and maxillofacial lesions. We retrospectively evaluated spectrum of mandibular lesions from a database of groundwork diagnostic OPGs. METHODS We reviewed a total of 2690 orthopentograms of patients with tooth ache and/or swelling, referred to the radiologist for the preliminary diagnosis. All osteolytic lesions more than 10 mm. and having characteristics of root abscess were included for evaluation. OPG taken for orthodontic work up, showing dental abscess less than 10 mm and OPG of patients with Gingival and T.M. joint pathologies were excluded. RESULTS In our study, we found 0.35% (95/2690 of patients were having a spectrum of mandibular lesions. The frequency of appearance of mandibular lesions on OPG was buccal-neoplasm>dentigerous-cysts>dental-cyst>neoplastic=traumatic-bone-cyst= osteomyelitis >kerato-cyst. The most frequent sites of these lesions were 80/103(77.6% molars, 14/103(13.6% incisors, and 9/103(8.7% angle of mandibles. No lesions were found on condyles. CONCLUSION The present study proves that OPG is a first

  8. CT-guided biopsy of thoracic lesions with a novel wire-based needle guide device - initial experiences

    Energy Technology Data Exchange (ETDEWEB)

    Kroepil, Patric; Bilk, Philip; Quentin, Michael; Miese, Falk R; Lanzman, Rotem S; Scherer, Axel (Dept. of Radiology, Medical Faculty, Univ. Duesseldorf, Duesseldorf (Germany)), email: Patric.Kroepil@med.uni-duesseldorf.de

    2011-10-15

    Background Biopsies guided by computed tomography (CT) play an important role in clinical practice. A short duration, minimal radiation dose and complication rate are of particular interest. Purpose To evaluate the potential of a novel self-manufactured wire-based needle guide device for CT-guided thoracic biopsies with respect to radiation dose, intervention time and complication rate. Material and Methods Forty patients that underwent CT-guided biopsies of thoracic lesions were included in this study and assigned to two groups. Patients in group A (n = 20, mean age 69 +- 8.4 years) underwent biopsies with a novel wire-based needle guide device, while patients in group B (n = 20, mean age 68.4 +- 10.1 years) were biopsied without a needle guide device. The novel self-manufactured needle guide device consists of an iron/zinc wire modelled to a ring with a flexible arm and an eye at the end of the arm to stabilize the biopsy needle in the optimal position during intervention. Predefined parameters (radiation dose, number of acquired CT-slices, duration of intervention, complications) were compared between both groups. Results Mean radiation dose (CTDIvol 192 mGy versus 541 mGy; P = 0.001) and the number of acquired slices during intervention (n = 49 +- 33 vs. n = 126 +- 78; P = 0.001) were significantly lower in group A compared with group B. Intervention time in group A (13.1 min) was significantly lower than in group B (18.5 min, P < 0.01). A pneumothorax as peri-interventional complication was observed less frequent after device assisted biopsies (n = 4 vs. n = 8, n.s.). Conclusion The novel wire-based needle guide device is a promising tool to facilitate CT-guided thoracic biopsies reducing radiation dose, intervention time, and related complications. Further studies are mandatory to confirm these initial results

  9. CT-guided biopsy of thoracic lesions with a novel wire-based needle guide device - initial experiences

    International Nuclear Information System (INIS)

    Kroepil, Patric; Bilk, Philip; Quentin, Michael; Miese, Falk R; Lanzman, Rotem S; Scherer, Axel

    2011-01-01

    Background Biopsies guided by computed tomography (CT) play an important role in clinical practice. A short duration, minimal radiation dose and complication rate are of particular interest. Purpose To evaluate the potential of a novel self-manufactured wire-based needle guide device for CT-guided thoracic biopsies with respect to radiation dose, intervention time and complication rate. Material and Methods Forty patients that underwent CT-guided biopsies of thoracic lesions were included in this study and assigned to two groups. Patients in group A (n = 20, mean age 69 ± 8.4 years) underwent biopsies with a novel wire-based needle guide device, while patients in group B (n = 20, mean age 68.4 ± 10.1 years) were biopsied without a needle guide device. The novel self-manufactured needle guide device consists of an iron/zinc wire modelled to a ring with a flexible arm and an eye at the end of the arm to stabilize the biopsy needle in the optimal position during intervention. Predefined parameters (radiation dose, number of acquired CT-slices, duration of intervention, complications) were compared between both groups. Results Mean radiation dose (CTDIvol 192 mGy versus 541 mGy; P = 0.001) and the number of acquired slices during intervention (n = 49 ± 33 vs. n = 126 ± 78; P = 0.001) were significantly lower in group A compared with group B. Intervention time in group A (13.1 min) was significantly lower than in group B (18.5 min, P < 0.01). A pneumothorax as peri-interventional complication was observed less frequent after device assisted biopsies (n = 4 vs. n = 8, n.s.). Conclusion The novel wire-based needle guide device is a promising tool to facilitate CT-guided thoracic biopsies reducing radiation dose, intervention time, and related complications. Further studies are mandatory to confirm these initial results

  10. Positioning Reduction of Deep Space Probes Based on VLBI Tracking

    Science.gov (United States)

    Qiao, S. B.

    2011-11-01

    In the background of the Chinese Lunar Exploration Project and the Yinghuo Project, through theoretical analysis, algorithm study, software development, data simulation, real data processing and so on, the positioning reductions of the European lunar satellite Smart-1 and Mars Express (MEX) satellite, as well as the Chinese Chang'e-1 (CE-1) and Chang'e-2 (CE-2) satellites are accomplished by using VLBI and USB tracking data in this dissertation. The progress is made in various aspects including the development of theoretical model, the construction of observation equation, the analysis of the condition of normal equation, the selection and determination of the constraint, the analysis of data simulation, the detection of outliers in observations, the maintenance of the stability of the solution of parameters, the development of the practical software system, the processing of the real tracking data and so on. The details of the research progress in this dissertation are written as follows: (1) The algorithm is analyzed concerning the positioning reduction of the deep spacecraft based on VLBI tracking data. Through data simulation, it is analyzed for the effects of the bias in predicted orbit, the white noises and systematic errors in VLBI delays, and USB ranges on the positioning reduction of spacecraft. Results show that it is preferable to suppress the dispersion of positioning data points by applying the constraint of geocentric distance of spacecraft when there are only VLBI tracking data. The positioning solution is a biased estimate via observations of three VLBI stations. For the case of four tracking stations, the uncertainty of the constraint should be in accordance with the bias in the predicted orbit. White noises in delays and ranges mainly result in dispersion of the sequence of positioning data points. If there is the systematic error of observations, the systematic offset of the positioning results is caused, and there are trend jumps in the shape of

  11. Platelet lysate formulations based on mucoadhesive polymers for the treatment of corneal lesions.

    Science.gov (United States)

    Sandri, Giuseppina; Bonferoni, Maria Cristina; Rossi, Silvia; Ferrari, Franca; Mori, Michela; Del Fante, Claudia; Perotti, Cesare; Scudeller, Luigia; Caramella, Carla

    2011-02-01

    Growth factors contained in platelet α-granules initiate and modulate tissue repair and are proposed for the treatment of soft and hard-tissue surgical conditions and in the management of non-healing wounds. Platelet lysate is a hemoderivative obtained from platelet-rich plasma and is capable of releasing a pool of growth factors. Many medical and surgical techniques have been proposed for the treatment of corneal lesions; management of these conditions remains problematic and healing with standard protocols is unattainable. The aim of this study was to develop formulations suitable for prolonging the contact of platelet lysate with the damaged cornea for the time necessary to exert a therapeutic effect. Two vehicles, one based on polyacrylic acid and one based on chitosan, were autoclaved and loaded with platelet lysate and the resultant formulations were characterized for rheology, mucoadhesion, vehicle compatibility and stability. The proliferation effect was tested on two cell culture types (rabbit corneal epithelial cells and fibroblasts). An in-vitro wound-healing test was performed on fibroblasts. In both cases the formulations were compared with platelet lysate diluted with saline at the same concentration. Both formulations maintained the rheological and mucoadhesive properties of the vehicles and the proliferative activity of platelet lysate. The chitosan formulation was able to significantly enhance epithelial cell growth even after storage of up to 2 weeks (in-use conditions), while the polyacrylic acid formulation was less efficient, probably due to the characteristics of the cell model used. The in-vitro wound-healing test performed on fibroblasts confirmed the differences between the two vehicles. The effect induced by the platelet lysate and chitosan formulation was faster than that of the polyacrylic acid formulation and complete in-vitro wound repair was achieved within 48 h. © 2010 The Authors. JPP © 2010 Royal Pharmaceutical Society.

  12. Position-based quantum cryptography over untrusted networks

    International Nuclear Information System (INIS)

    Nadeem, Muhammad

    2014-01-01

    In this article, we propose quantum position verification (QPV) schemes where all the channels are untrusted except the position of the prover and distant reference stations of verifiers. We review and analyze the existing QPV schemes containing some pre-shared data between the prover and verifiers. Most of these schemes are based on non-cryptographic assumptions, i.e. quantum/classical channels between the verifiers are secure. It seems impractical in an environment fully controlled by adversaries and would lead to security compromise in practical implementations. However, our proposed formula for QPV is more robust, secure and according to the standard assumptions of cryptography. Furthermore, once the position of the prover is verified, our schemes establish secret keys in parallel and can be used for authentication and secret communication between the prover and verifiers. (paper)

  13. A modular positive feedback-based gene amplifier

    Directory of Open Access Journals (Sweden)

    Bhalerao Kaustubh D

    2010-02-01

    Full Text Available Abstract Background Positive feedback is a common mechanism used in the regulation of many gene circuits as it can amplify the response to inducers and also generate binary outputs and hysteresis. In the context of electrical circuit design, positive feedback is often considered in the design of amplifiers. Similar approaches, therefore, may be used for the design of amplifiers in synthetic gene circuits with applications, for example, in cell-based sensors. Results We developed a modular positive feedback circuit that can function as a genetic signal amplifier, heightening the sensitivity to inducer signals as well as increasing maximum expression levels without the need for an external cofactor. The design utilizes a constitutively active, autoinducer-independent variant of the quorum-sensing regulator LuxR. We experimentally tested the ability of the positive feedback module to separately amplify the output of a one-component tetracycline sensor and a two-component aspartate sensor. In each case, the positive feedback module amplified the response to the respective inducers, both with regards to the dynamic range and sensitivity. Conclusions The advantage of our design is that the actual feedback mechanism depends only on a single gene and does not require any other modulation. Furthermore, this circuit can amplify any transcriptional signal, not just one encoded within the circuit or tuned by an external inducer. As our design is modular, it can potentially be used as a component in the design of more complex synthetic gene circuits.

  14. A signal strength priority based position estimation for mobile platforms

    Science.gov (United States)

    Kalgikar, Bhargav; Akopian, David; Chen, Philip

    2010-01-01

    Global Positioning System (GPS) products help to navigate while driving, hiking, boating, and flying. GPS uses a combination of orbiting satellites to determine position coordinates. This works great in most outdoor areas, but the satellite signals are not strong enough to penetrate inside most indoor environments. As a result, a new strain of indoor positioning technologies that make use of 802.11 wireless LANs (WLAN) is beginning to appear on the market. In WLAN positioning the system either monitors propagation delays between wireless access points and wireless device users to apply trilateration techniques or it maintains the database of location-specific signal fingerprints which is used to identify the most likely match of incoming signal data with those preliminary surveyed and saved in the database. In this paper we investigate the issue of deploying WLAN positioning software on mobile platforms with typically limited computational resources. We suggest a novel received signal strength rank order based location estimation system to reduce computational loads with a robust performance. The proposed system performance is compared to conventional approaches.

  15. Unconditionally secure commitment in position-based quantum cryptography.

    Science.gov (United States)

    Nadeem, Muhammad

    2014-10-27

    A new commitment scheme based on position-verification and non-local quantum correlations is presented here for the first time in literature. The only credential for unconditional security is the position of committer and non-local correlations generated; neither receiver has any pre-shared data with the committer nor does receiver require trusted and authenticated quantum/classical channels between him and the committer. In the proposed scheme, receiver trusts the commitment only if the scheme itself verifies position of the committer and validates her commitment through non-local quantum correlations in a single round. The position-based commitment scheme bounds committer to reveal valid commitment within allocated time and guarantees that the receiver will not be able to get information about commitment unless committer reveals. The scheme works for the commitment of both bits and qubits and is equally secure against committer/receiver as well as against any third party who may have interests in destroying the commitment. Our proposed scheme is unconditionally secure in general and evades Mayers and Lo-Chau attacks in particular.

  16. Adaptive algorithm for mobile user positioning based on environment estimation

    Directory of Open Access Journals (Sweden)

    Grujović Darko

    2014-01-01

    Full Text Available This paper analyzes the challenges to realize an infrastructure independent and a low-cost positioning method in cellular networks based on RSS (Received Signal Strength parameter, auxiliary timing parameter and environment estimation. The proposed algorithm has been evaluated using field measurements collected from GSM (Global System for Mobile Communications network, but it is technology independent and can be applied in UMTS (Universal Mobile Telecommunication Systems and LTE (Long-Term Evolution networks, also.

  17. [Study on pulmonary lesions in which nontuberculous mycobacteria were detected by percutaneous aspiration--a proposal to add "culture positivity of percutaneous aspiration material" to the bacteriological diagnostic criteria of pulmonary nontuberculous mycobacterial diseases].

    Science.gov (United States)

    Nakahara, Yasuharu; Mochizuki, Yoshiro; Kawamura, Tetsuji; Sasaki, Shin; Morimoto, Akie; Mizumori, Yasuyuki; Tsukamoto, Hiroaki; Watanabe, Etsuko; Yokoyama, Toshihide

    2013-03-01

    Culture positivity of percutaneous aspiration material" is not included in the current bacteriological criteria for diagnosis of pulmonary nontuberculous mycobacterial (NTM) diseases, which were published by the Infectious Diseases Society of America (IDSA)/American Thoracic Society (ATS) in 2007 or those released by the Japanese Society for Tuberculosis in 2008. However, percutaneous aspiration is a reliable technique for the detection of causative microorganisms isolated from the focus of infection. We discuss the benefits of including positive culture of percutaneous aspiration material in the bacteriological diagnostic criteria of pulmonary NTM diseases. We reviewed the radiological images and clinical courses of pulmonary diseases in which NTM cultures were obtained from percutaneously aspirated materials at our hospital from 1991 to 2011. Aspiration was carried out under local anesthesia, usually with fluoroscopic guidance. After percutaneous insertion of a 22-gauge needle attached to a 20-mL syringe containing about 3 mL of saline, the lesion specimen was withdrawn together with the saline. After the needle was pulled out, the aspirated material and saline were transferred to test tubes for cytological and microbiological examinations. In patients with thin-walled cavitary lesions, saline was injected into the cavity and then aspirated. Percutaneous aspiration was performed in 2,742 patients and NTM disease was detected in 51 patients. Of these 51 patients, 12 had solitary nodular lesions, and in many of these patients, no NTM bacilli could be detected in the sputa or bronchial washing specimens. Mycobacterium avium was identified in 10 of the 12 cases. Four of these 10 patients were followed up after their diagnosis without any treatment: 3 showed spontaneous reduction in lesion size, while 1 patient's condition remained unchanged. Four of the remaining 6 cases were treated with anti-NTM medications, and lesion size reduced in 2 cases, while no change or

  18. Design about position and display of GPS based on singlechip

    Directory of Open Access Journals (Sweden)

    WU Dongdong

    2016-02-01

    Full Text Available GPS is used in ships,vehicles,aircraft and other moving objects.GPS also has the important application in vehicle monitoring system.However,with the expansion of the specialized functions of GPS,its high cost makes so many ordinary consumers unbearable.This paper proposes a simple design of GPS based on singlechip.The design Improves the basic utility functions of system and adds the speed and mileage measurement.GPS module uses the differential technology to improve the positioning accuracy.Therefore,the navigation device is compact,easy to carry and of high precision positioning.Through getting the data of 3D coordinates from the observation point and the factor of position accuracy,the average of which is less than five,indicating that the position accuracy can be improved by differential technology to achieve the desired range.At last,the feasibility of this design is verified through the current data tested in the outdoors.

  19. Uav Positioning and Collision Avoidance Based on RSS Measurements

    Science.gov (United States)

    Masiero, A.; Fissore, F.; Guarnieri, A.; Pirotti, F.; Vettore, A.

    2015-08-01

    In recent years, Unmanned Aerial Vehicles (UAVs) are attracting more and more attention in both the research and industrial communities: indeed, the possibility to use them in a wide range of remote sensing applications makes them a very flexible and attractive solution in both civil and commercial cases (e.g. precision agriculture, security and control, monitoring of sites, exploration of areas difficult to reach). Most of the existing UAV positioning systems rely on the use of the GPS signal. Despite this can be a satisfactory solution in open environments where the GPS signal is available, there are several operating conditions of interest where it is unavailable or unreliable (e.g. close to high buildings, or mountains, in indoor environments). Consequently, a different approach has to be adopted in these cases. This paper considers the use ofWiFi measurements in order to obtain position estimations of the device of interest. More specifically, to limit the costs for the devices involved in the positioning operations, an approach based on radio signal strengths (RSS) measurements is considered. Thanks to the use of a Kalman filter, the proposed approach takes advantage of the temporal dynamic of the device of interest in order to improve the positioning results initially provided by means of maximum likelihood estimations. The considered UAVs are assumed to be provided with communication devices, which can allow them to communicate with each other in order to improve their cooperation abilities. In particular, the collision avoidance problem is examined in this work.

  20. Accurate position estimation methods based on electrical impedance tomography measurements

    Science.gov (United States)

    Vergara, Samuel; Sbarbaro, Daniel; Johansen, T. A.

    2017-08-01

    Electrical impedance tomography (EIT) is a technology that estimates the electrical properties of a body or a cross section. Its main advantages are its non-invasiveness, low cost and operation free of radiation. The estimation of the conductivity field leads to low resolution images compared with other technologies, and high computational cost. However, in many applications the target information lies in a low intrinsic dimensionality of the conductivity field. The estimation of this low-dimensional information is addressed in this work. It proposes optimization-based and data-driven approaches for estimating this low-dimensional information. The accuracy of the results obtained with these approaches depends on modelling and experimental conditions. Optimization approaches are sensitive to model discretization, type of cost function and searching algorithms. Data-driven methods are sensitive to the assumed model structure and the data set used for parameter estimation. The system configuration and experimental conditions, such as number of electrodes and signal-to-noise ratio (SNR), also have an impact on the results. In order to illustrate the effects of all these factors, the position estimation of a circular anomaly is addressed. Optimization methods based on weighted error cost functions and derivate-free optimization algorithms provided the best results. Data-driven approaches based on linear models provided, in this case, good estimates, but the use of nonlinear models enhanced the estimation accuracy. The results obtained by optimization-based algorithms were less sensitive to experimental conditions, such as number of electrodes and SNR, than data-driven approaches. Position estimation mean squared errors for simulation and experimental conditions were more than twice for the optimization-based approaches compared with the data-driven ones. The experimental position estimation mean squared error of the data-driven models using a 16-electrode setup was less

  1. Differential diagnosis of mesiotemporal lesions: case report of neurosyphilis

    International Nuclear Information System (INIS)

    Vieira Santos, A.; Matias, S.; Saraiva, P.; Goulao, A.

    2005-01-01

    We report a clinical and imaging case of suspected herpes simplex encephalitis subsequently diagnosed as neurosyphilis based on positive antibodies in the CSF. MRI of the brain showed cortical and subcortical lesions in the mesial temporal region, septal area, insula and cingulated gyrus of the right cerebral hemisphere. Neurosyphilis should be included in the differential diagnosis of mesial temporal region lesions on MRI. (orig.)

  2. Video-based beam position monitoring at CHESS

    Science.gov (United States)

    Revesz, Peter; Pauling, Alan; Krawczyk, Thomas; Kelly, Kevin J.

    2012-10-01

    CHESS has pioneered the development of X-ray Video Beam Position Monitors (VBPMs). Unlike traditional photoelectron beam position monitors that rely on photoelectrons generated by the fringe edges of the X-ray beam, with VBPMs we collect information from the whole cross-section of the X-ray beam. VBPMs can also give real-time shape/size information. We have developed three types of VBPMs: (1) VBPMs based on helium luminescence from the intense white X-ray beam. In this case the CCD camera is viewing the luminescence from the side. (2) VBPMs based on luminescence of a thin (~50 micron) CVD diamond sheet as the white beam passes through it. The CCD camera is placed outside the beam line vacuum and views the diamond fluorescence through a viewport. (3) Scatter-based VBPMs. In this case the white X-ray beam passes through a thin graphite filter or Be window. The scattered X-rays create an image of the beam's footprint on an X-ray sensitive fluorescent screen using a slit placed outside the beam line vacuum. For all VBPMs we use relatively inexpensive 1.3 Mega-pixel CCD cameras connected via USB to a Windows host for image acquisition and analysis. The VBPM host computers are networked and provide live images of the beam and streams of data about the beam position, profile and intensity to CHESS's signal logging system and to the CHESS operator. The operational use of VBPMs showed great advantage over the traditional BPMs by providing direct visual input for the CHESS operator. The VBPM precision in most cases is on the order of ~0.1 micron. On the down side, the data acquisition frequency (50-1000ms) is inferior to the photoelectron based BPMs. In the future with the use of more expensive fast cameras we will be able create VBPMs working in the few hundreds Hz scale.

  3. Embedded wavelet-based face recognition under variable position

    Science.gov (United States)

    Cotret, Pascal; Chevobbe, Stéphane; Darouich, Mehdi

    2015-02-01

    For several years, face recognition has been a hot topic in the image processing field: this technique is applied in several domains such as CCTV, electronic devices delocking and so on. In this context, this work studies the efficiency of a wavelet-based face recognition method in terms of subject position robustness and performance on various systems. The use of wavelet transform has a limited impact on the position robustness of PCA-based face recognition. This work shows, for a well-known database (Yale face database B*), that subject position in a 3D space can vary up to 10% of the original ROI size without decreasing recognition rates. Face recognition is performed on approximation coefficients of the image wavelet transform: results are still satisfying after 3 levels of decomposition. Furthermore, face database size can be divided by a factor 64 (22K with K = 3). In the context of ultra-embedded vision systems, memory footprint is one of the key points to be addressed; that is the reason why compression techniques such as wavelet transform are interesting. Furthermore, it leads to a low-complexity face detection stage compliant with limited computation resources available on such systems. The approach described in this work is tested on three platforms from a standard x86-based computer towards nanocomputers such as RaspberryPi and SECO boards. For K = 3 and a database with 40 faces, the execution mean time for one frame is 0.64 ms on a x86-based computer, 9 ms on a SECO board and 26 ms on a RaspberryPi (B model).

  4. Resection of highly language-eloquent brain lesions based purely on rTMS language mapping without awake surgery.

    Science.gov (United States)

    Ille, Sebastian; Sollmann, Nico; Butenschoen, Vicki M; Meyer, Bernhard; Ringel, Florian; Krieg, Sandro M

    2016-12-01

    The resection of left-sided perisylvian brain lesions harbours the risk of postoperative language impairment. Therefore the individual patient's language distribution is investigated by intraoperative direct cortical stimulation (DCS) during awake surgery. Yet, not all patients qualify for awake surgery. Non-invasive language mapping by repetitive navigated transcranial magnetic stimulation (rTMS) has frequently shown a high correlation in comparison with the results of DCS language mapping in terms of language-negative brain regions. The present study analyses the extent of resection (EOR) and functional outcome of patients who underwent left-sided perisylvian resection of brain lesions based purely on rTMS language mapping. Four patients with left-sided perisylvian brain lesions (two gliomas WHO III, one glioblastoma, one cavernous angioma) underwent rTMS language mapping prior to surgery. Data from rTMS language mapping and rTMS-based diffusion tensor imaging fibre tracking (DTI-FT) were transferred to the intraoperative neuronavigation system. Preoperatively, 5 days after surgery (POD5), and 3 months after surgery (POM3) clinical follow-up examinations were performed. No patient suffered from a new surgery-related aphasia at POM3. Three patients underwent complete resection immediately, while one patient required a second rTMS-based resection some days later to achieve the final, complete resection. The present study shows for the first time the feasibility of successfully resecting language-eloquent brain lesions based purely on the results of negative language maps provided by rTMS language mapping and rTMS-based DTI-FT. In very select cases, this technique can provide a rescue strategy with an optimal functional outcome and EOR when awake surgery is not feasible.

  5. Beam based measurement of beam position monitor electrode gains

    Directory of Open Access Journals (Sweden)

    D. L. Rubin

    2010-09-01

    Full Text Available Low emittance tuning at the Cornell Electron Storage Ring (CESR test accelerator depends on precision measurement of vertical dispersion and transverse coupling. The CESR beam position monitors (BPMs consist of four button electrodes, instrumented with electronics that allow acquisition of turn-by-turn data. The response to the beam will vary among the four electrodes due to differences in electronic gain and/or misalignment. This variation in the response of the BPM electrodes will couple real horizontal offset to apparent vertical position, and introduce spurious measurements of coupling and vertical dispersion. To alleviate this systematic effect, a beam based technique to measure the relative response of the four electrodes has been developed. With typical CESR parameters, simulations show that turn-by-turn BPM data can be used to determine electrode gains to within ∼0.1%.

  6. Beam based measurement of beam position monitor electrode gains

    Science.gov (United States)

    Rubin, D. L.; Billing, M.; Meller, R.; Palmer, M.; Rendina, M.; Rider, N.; Sagan, D.; Shanks, J.; Strohman, C.

    2010-09-01

    Low emittance tuning at the Cornell Electron Storage Ring (CESR) test accelerator depends on precision measurement of vertical dispersion and transverse coupling. The CESR beam position monitors (BPMs) consist of four button electrodes, instrumented with electronics that allow acquisition of turn-by-turn data. The response to the beam will vary among the four electrodes due to differences in electronic gain and/or misalignment. This variation in the response of the BPM electrodes will couple real horizontal offset to apparent vertical position, and introduce spurious measurements of coupling and vertical dispersion. To alleviate this systematic effect, a beam based technique to measure the relative response of the four electrodes has been developed. With typical CESR parameters, simulations show that turn-by-turn BPM data can be used to determine electrode gains to within ˜0.1%.

  7. Cellular automaton-based position sensitive detector equalization

    Energy Technology Data Exchange (ETDEWEB)

    Ferrando, Nestor [Grupo de Diseno de Sistemas Digitales, Instituto de Aplicaciones de las Tecnologias de la Informacion y de las Comunicaciones Avanzadas, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain)], E-mail: nesferjo@upvnet.upv.es; Herrero, V.; Cerda, J.; Lerche, C.W.; Colom, R.J.; Gadea, R.; Martinez, J.D.; Monzo, J.M.; Mateo, F.; Sebastia, A.; Benlloch, J.M. [Grupo de Diseno de Sistemas Digitales, Instituto de Aplicaciones de las Tecnologias de la Informacion y de las Comunicaciones Avanzadas, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain)

    2009-06-01

    Indirect position detectors based on scintillator crystals lack of spacial uniformity in their response. This happens due to crystal inhomogeneities and gain differences among the photomultiplier anodes. In order to solve this, PESIC, an integrated front-end for multianode photomultiplier based nuclear imaging devices was created. One of its main features is the digitally programmable gain adjustment for every photomultiplier output. On another front, cellular automata have been proved to be a useful method for dynamic system modeling. In this paper, a cellular automaton which emulates the behavior of the scintillator crystal, the photomultiplier and the front-end is introduced. Thanks to this model, an automatic energy-based calibration of the detector can be done by configuring the cellular automaton with experimental data and making it evolve up to an stable state. This can be useful as a precalibration method of the detector.

  8. Cellular automaton-based position sensitive detector equalization

    International Nuclear Information System (INIS)

    Ferrando, Nestor; Herrero, V.; Cerda, J.; Lerche, C.W.; Colom, R.J.; Gadea, R.; Martinez, J.D.; Monzo, J.M.; Mateo, F.; Sebastia, A.; Benlloch, J.M.

    2009-01-01

    Indirect position detectors based on scintillator crystals lack of spacial uniformity in their response. This happens due to crystal inhomogeneities and gain differences among the photomultiplier anodes. In order to solve this, PESIC, an integrated front-end for multianode photomultiplier based nuclear imaging devices was created. One of its main features is the digitally programmable gain adjustment for every photomultiplier output. On another front, cellular automata have been proved to be a useful method for dynamic system modeling. In this paper, a cellular automaton which emulates the behavior of the scintillator crystal, the photomultiplier and the front-end is introduced. Thanks to this model, an automatic energy-based calibration of the detector can be done by configuring the cellular automaton with experimental data and making it evolve up to an stable state. This can be useful as a precalibration method of the detector.

  9. Disruption of Smad-dependent signaling for growth of GST-P-positive lesions from the early stage in a rat two-stage hepatocarcinogenesis model

    International Nuclear Information System (INIS)

    Ichimura, Ryohei; Mizukami, Sayaka; Takahashi, Miwa; Taniai, Eriko; Kemmochi, Sayaka; Mitsumori, Kunitoshi; Shibutani, Makoto

    2010-01-01

    To clarify the involvement of signaling of transforming growth factor (TGF)-β during the hepatocarcinogenesis, the immunohistochemical distribution of related molecules was analyzed in relation with liver cell lesions expressing glutathione S-transferase placental form (GST-P) during liver tumor promotion by fenbendazole, phenobarbital, piperonyl butoxide, or thioacetamide, using rats. Our study focused on early-stage promotion (6 weeks after starting promotion) and late-stage promotion (57 weeks after starting promotion). With regard to Smad-dependent signaling, cytoplasmic accumulation of phosphorylated Smad (phospho-Smad)-2/3 - identified as Smad3 by later immunoblot analysis - increased in the subpopulation of GST-P + foci, while Smad4, a nuclear transporter of Smad2/3, decreased during early-stage promotion. By late-stage promotion, GST-P + lesions lacking phospho-Smad2/3 had increased in accordance with lesion development from foci to carcinomas, while Smad4 largely disappeared in most proliferative lesions. With regard to Smad-independent mitogen-activated protein kinases, GST-P + foci that co-expressed phospho-p38 mitogen-activated protein kinase increased during early-stage promotion; however, p38-downstream phospho-activating transcriptional factor (ATF)-2, ATF3, and phospho-c-Myc, were inversely downregulated without relation to promotion. By late-stage promotion, proliferative lesions downregulated phospho-ATF2 and phospho-c-Myc along with lesion development, as with downregulation of phospho-p38 in all lesions. These results suggest that from the early stages, carcinogenic processes were facilitated by disruption of tumor suppressor functions of Smad-dependent signaling, while Smad-independent activation of p38 was an early-stage phenomenon. GST-P - foci induced by promotion with agonists of peroxisome proliferator-activated receptor-α did not change Smad expression, suggesting an aberration in the Smad-dependent signaling prerequisites for induction

  10. Spectral embedding based active contour (SEAC) for lesion segmentation on breast dynamic contrast enhanced magnetic resonance imaging.

    Science.gov (United States)

    Agner, Shannon C; Xu, Jun; Madabhushi, Anant

    2013-03-01

    Segmentation of breast lesions on dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) is the first step in lesion diagnosis in a computer-aided diagnosis framework. Because manual segmentation of such lesions is both time consuming and highly susceptible to human error and issues of reproducibility, an automated lesion segmentation method is highly desirable. Traditional automated image segmentation methods such as boundary-based active contour (AC) models require a strong gradient at the lesion boundary. Even when region-based terms are introduced to an AC model, grayscale image intensities often do not allow for clear definition of foreground and background region statistics. Thus, there is a need to find alternative image representations that might provide (1) strong gradients at the margin of the object of interest (OOI); and (2) larger separation between intensity distributions and region statistics for the foreground and background, which are necessary to halt evolution of the AC model upon reaching the border of the OOI. In this paper, the authors introduce a spectral embedding (SE) based AC (SEAC) for lesion segmentation on breast DCE-MRI. SE, a nonlinear dimensionality reduction scheme, is applied to the DCE time series in a voxelwise fashion to reduce several time point images to a single parametric image where every voxel is characterized by the three dominant eigenvectors. This parametric eigenvector image (PrEIm) representation allows for better capture of image region statistics and stronger gradients for use with a hybrid AC model, which is driven by both boundary and region information. They compare SEAC to ACs that employ fuzzy c-means (FCM) and principal component analysis (PCA) as alternative image representations. Segmentation performance was evaluated by boundary and region metrics as well as comparing lesion classification using morphological features from SEAC, PCA+AC, and FCM+AC. On a cohort of 50 breast DCE-MRI studies, Pr

  11. Intra-lesional spatial correlation of static and dynamic FET-PET parameters with MRI-based cerebral blood volume in patients with untreated glioma

    Energy Technology Data Exchange (ETDEWEB)

    Goettler, Jens; Preibisch, Christine [TU Muenchen, Department of Neuroradiology, Klinikum rechts der Isar, Munich (Germany); TU Muenchen, TUM Neuroimaging Center (TUM-NIC), Klinikum rechts der Isar, Munich (Germany); Lukas, Mathias; Mustafa, Mona; Schwaiger, Markus; Pyka, Thomas [TU Muenchen, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Kluge, Anne; Kaczmarz, Stephan; Zimmer, Claus [TU Muenchen, Department of Neuroradiology, Klinikum rechts der Isar, Munich (Germany); Gempt, Jens; Ringel, Florian; Meyer, Bernhard [TU Muenchen, Department of Neurosurgery, Klinikum rechts der Isar, Munich (Germany); Foerster, Stefan [TU Muenchen, TUM Neuroimaging Center (TUM-NIC), Klinikum rechts der Isar, Munich (Germany); TU Muenchen, Department of Nuclear Medicine, Klinikum rechts der Isar, Munich (Germany); Klinikum Bayreuth, Department of Nuclear Medicine, Bayreuth (Germany)

    2017-03-15

    {sup 18}F-fluorethyltyrosine-(FET)-PET and MRI-based relative cerebral blood volume (rCBV) have both been used to characterize gliomas. Recently, inter-individual correlations between peak static FET-uptake and rCBV have been reported. Herein, we assess the local intra-lesional relation between FET-PET parameters and rCBV. Thirty untreated glioma patients (27 high-grade) underwent simultaneous PET/MRI on a 3 T hybrid scanner obtaining structural and dynamic susceptibility contrast sequences. Static FET-uptake and dynamic FET-slope were correlated with rCBV within tumour hotspots across patients and intra-lesionally using a mixed-effects model to account for inter-individual variation. Furthermore, maximal congruency of tumour volumes defined by FET-uptake and rCBV was determined. While the inter-individual relationship between peak static FET-uptake and rCBV could be confirmed, our intra-lesional, voxel-wise analysis revealed significant positive correlations (median r = 0.374, p < 0.0001). Similarly, significant inter- and intra-individual correlations were observed between FET-slope and rCBV. However, rCBV explained only 12% of the static and 5% of the dynamic FET-PET variance and maximal overlap of respective tumour volumes was 37% on average. Our results show that the relation between peak values of MR-based rCBV and static FET-uptake can also be observed intra-individually on a voxel basis and also applies to a dynamic FET parameter, possibly determining hotspots of higher biological malignancy. However, just a small part of the FET-PET signal variance is explained by rCBV and tumour volumes determined by the two modalities showed only moderate overlap. These findings indicate that FET-PET and MR-based rCBV provide both congruent and complimentary information on glioma biology. (orig.)

  12. Intra-lesional spatial correlation of static and dynamic FET-PET parameters with MRI-based cerebral blood volume in patients with untreated glioma.

    Science.gov (United States)

    Göttler, Jens; Lukas, Mathias; Kluge, Anne; Kaczmarz, Stephan; Gempt, Jens; Ringel, Florian; Mustafa, Mona; Meyer, Bernhard; Zimmer, Claus; Schwaiger, Markus; Förster, Stefan; Preibisch, Christine; Pyka, Thomas

    2017-03-01

    18 F-fluorethyltyrosine-(FET)-PET and MRI-based relative cerebral blood volume (rCBV) have both been used to characterize gliomas. Recently, inter-individual correlations between peak static FET-uptake and rCBV have been reported. Herein, we assess the local intra-lesional relation between FET-PET parameters and rCBV. Thirty untreated glioma patients (27 high-grade) underwent simultaneous PET/MRI on a 3 T hybrid scanner obtaining structural and dynamic susceptibility contrast sequences. Static FET-uptake and dynamic FET-slope were correlated with rCBV within tumour hotspots across patients and intra-lesionally using a mixed-effects model to account for inter-individual variation. Furthermore, maximal congruency of tumour volumes defined by FET-uptake and rCBV was determined. While the inter-individual relationship between peak static FET-uptake and rCBV could be confirmed, our intra-lesional, voxel-wise analysis revealed significant positive correlations (median r = 0.374, p dynamic FET-PET variance and maximal overlap of respective tumour volumes was 37% on average. Our results show that the relation between peak values of MR-based rCBV and static FET-uptake can also be observed intra-individually on a voxel basis and also applies to a dynamic FET parameter, possibly determining hotspots of higher biological malignancy. However, just a small part of the FET-PET signal variance is explained by rCBV and tumour volumes determined by the two modalities showed only moderate overlap. These findings indicate that FET-PET and MR-based rCBV provide both congruent and complimentary information on glioma biology.

  13. Hidden in Plain Sight: Subtle Effects of the 8-Oxoguanine Lesion on the Structure, Dynamics, and Thermodynamics of a 15-Base-Pair Oligodeoxynucleotide Duplex†

    Science.gov (United States)

    Crenshaw, Charisse M.; Wade, Jacqueline E.; Arthanari, Haribabu; Frueh, Dominique; Lane, Benjamin F.; Núñez, Megan E.

    2011-01-01

    The base lesion 8-oxoguanine is formed readily by oxidation of DNA, potentially leading to G→T transversion mutations. Despite the apparent similarity of 8-oxoguanine-cytosine base pairs to normal guanine-cytosine base pairs, cellular base excision repair systems effectively recognize the lesion base. Here we apply several techniques to examine a single 8-oxoguanine lesion at the center of a nonpalindromic 15-mer duplex oligonucleotide in an effort to determine what, if anything, distinguishes an 8-oxoguanine-cytosine base pair from a normal base pair. The lesion duplex is globally almost indistinguishable from the unmodified parent duplex using CD spectroscopy and UV melting thermodynamics. The DNA mismatch-detecting photocleavage agent Rh(bpy)2chrysi3+ cleaves only weakly and nonspecifically, revealing that the 8oxoG-C pair is locally stable at the level of the individual base pairs. NMR spectra are also consistent with a well-conserved B-form duplex structure. In the 2D NOESY spectra, base-sugar and imino-imino crosspeaks are strikingly similar between parent and lesion duplexes. Changes in chemical shift due to the 8oxoG lesion are localized to its complementary cytosine and to the 2–3 base pairs immediately flanking the lesion on the lesion strand. Residues further removed from the lesion are shown to be unperturbed by its presence. Notably, imino exchange experiments indicate that the 8-oxoguanine-cytosine pair is strong and stable, with an apparent equilibrium constant for opening equal to that of other internal guanine-cytosine base pairs, on the order of 10−6. This collection of experiments shows that the 8-oxoguanine-cytosine base pair is incredibly stable and similar to the native pair. PMID:21902242

  14. Image annotation based on positive-negative instances learning

    Science.gov (United States)

    Zhang, Kai; Hu, Jiwei; Liu, Quan; Lou, Ping

    2017-07-01

    Automatic image annotation is now a tough task in computer vision, the main sense of this tech is to deal with managing the massive image on the Internet and assisting intelligent retrieval. This paper designs a new image annotation model based on visual bag of words, using the low level features like color and texture information as well as mid-level feature as SIFT, and mixture the pic2pic, label2pic and label2label correlation to measure the correlation degree of labels and images. We aim to prune the specific features for each single label and formalize the annotation task as a learning process base on Positive-Negative Instances Learning. Experiments are performed using the Corel5K Dataset, and provide a quite promising result when comparing with other existing methods.

  15. Lesion activity assessment

    DEFF Research Database (Denmark)

    Ekstrand, K R; Zero, D T; Martignon, S

    2009-01-01

    in response to cariogenic plaque as well as lesion arrest. Based on this understanding, different clinical scoring systems have been developed to assess the severity/depth and activity of lesions. A recent system has been devised by the International Caries Detection and Assessment System Committee...

  16. A Solar Position Sensor Based on Image Vision.

    Science.gov (United States)

    Ruelas, Adolfo; Velázquez, Nicolás; Villa-Angulo, Carlos; Acuña, Alexis; Rosales, Pedro; Suastegui, José

    2017-07-29

    Solar collector technologies operate with better performance when the Sun beam direction is normal to the capturing surface, and for that to happen despite the relative movement of the Sun, solar tracking systems are used, therefore, there are rules and standards that need minimum accuracy for these tracking systems to be used in solar collectors' evaluation. Obtaining accuracy is not an easy job, hence in this document the design, construction and characterization of a sensor based on a visual system that finds the relative azimuth error and height of the solar surface of interest, is presented. With these characteristics, the sensor can be used as a reference in control systems and their evaluation. The proposed sensor is based on a microcontroller with a real-time clock, inertial measurement sensors, geolocation and a vision sensor, that obtains the angle of incidence from the sunrays' direction as well as the tilt and sensor position. The sensor's characterization proved how a measurement of a focus error or a Sun position can be made, with an accuracy of 0.0426° and an uncertainty of 0.986%, which can be modified to reach an accuracy under 0.01°. The validation of this sensor was determined showing the focus error on one of the best commercial solar tracking systems, a Kipp & Zonen SOLYS 2. To conclude, the solar tracking sensor based on a vision system meets the Sun detection requirements and components that meet the accuracy conditions to be used in solar tracking systems and their evaluation or, as a tracking and orientation tool, on photovoltaic installations and solar collectors.

  17. Last-position elimination-based learning automata.

    Science.gov (United States)

    Zhang, Junqi; Wang, Cheng; Zhou, MengChu

    2014-12-01

    An update scheme of the state probability vector of actions is critical for learning automata (LA). The most popular is the pursuit scheme that pursues the estimated optimal action and penalizes others. This paper proposes a reverse philosophy that leads to last-position elimination-based learning automata (LELA). The action graded last in terms of the estimated performance is penalized by decreasing its state probability and is eliminated when its state probability becomes zero. All active actions, that is, actions with nonzero state probability, equally share the penalized state probability from the last-position action at each iteration. The proposed LELA is characterized by the relaxed convergence condition for the optimal action, the accelerated step size of the state probability update scheme for the estimated optimal action, and the enriched sampling for the estimated nonoptimal actions. The proof of the ϵ-optimal property for the proposed algorithm is presented. Last-position elimination is a widespread philosophy in the real world and has proved to be also helpful for the update scheme of the learning automaton via the simulations of well-known benchmark environments. In the simulations, two versions of the LELA, using different selection strategies of the last action, are compared with the classical pursuit algorithms Discretized Pursuit Reward-Inaction (DP(RI)) and Discretized Generalized Pursuit Algorithm (DGPA). Simulation results show that the proposed schemes achieve significantly faster convergence and higher accuracy than the classical ones. Specifically, the proposed schemes reduce the interval to find the best parameter for a specific environment in the classical pursuit algorithms. Thus, they can have their parameter tuning easier to perform and can save much more time when applied to a practical case. Furthermore, the convergence curves and the corresponding variance coefficient curves of the contenders are illustrated to characterize their

  18. Laryngeal giant cell tumour presenting as a tongue base lesion causing severe dysphagia

    Directory of Open Access Journals (Sweden)

    Mohd Razi M. Saud, MBBS

    2018-04-01

    Full Text Available الملخص: أورام الخلايا العملاقة هي آفات حميدة وغير مألوفة تظهر في الحنجرة. قد يصاب المريض بصعوبة في البلع، وبحة في الصوت وتورم في الجهة الأمامية من الرقبة. أورام الخلايا العملاقة هي نادرة للغاية، وهناك حالات قليلة في الأدبيات المنشورة. نعرض لحالة إمرأة مسنة قدمت بصعوبة شديدة في البلع، وورم في قاعدة اللسان. أظهرت نتيجة الورم بأنه ورم الخلايا العملاقة في الحنجرة وتم علاجه بنجاح باستخدام المعالجة الكيميائية. Abstract: Giant cell tumours are benign lesions that are uncommonly found in the larynx. Patients with these tumours may present with dysphagia, hoarseness and anterior neck swelling. Giant cell tumours are extremely rare and only a few cases have been reported. We present a case of an elderly woman who presented with severe dysphagia and a mass at the base of her tongue. The mass was found to be a laryngeal giant cell tumour and was successfully treated with chemotherapy. الكلمات المفتاحية: أورام الخلايا العملاقة, الحنجرة, صعوبة البلع, دينوسوماب, المعالجة الكيميائية, Keywords: Chemotherapy, Denosumab, Dysphagia, Giant cell tumour, Larynx

  19. ALA-based fluorescent diagnosis of malignant oral lesions in the presence of bacterial porphyrin formation

    Science.gov (United States)

    Schleier, P.; Berndt, A.; Zinner, K.; Zenk, W.; Dietel, W.; Pfister, W.

    2006-02-01

    The aminolevulinic acid (5-ALA) -based fluorescence diagnosis has been found to be promising for an early detection and demarcation of superficial oral squamous cell carcinomas (OSCC). This method has previously demonstrated high sensitivity, however this clinical trial showed a specificity of approximately 62 %. This specificity was mainly restricted by tumor detection in the oral cavity in the presence of bacteria. After topical ALA application in the mouth of patients with previously diagnosed OSSC, red fluorescent areas were observed which did not correlate to confirm histological findings. Swabs and plaque samples were taken from 44 patients and cultivated microbiologically. Fluorescence was investigated (OMA-system) from 32 different bacteria strains found naturally in the oral cavity. After ALA incubation, 30 of 32 strains were found to synthesize fluorescent porphyrins, mainly Protoporphyrin IX. Also multiple fluorescent spectra were obtained having peak wavelengths of 636 nm and around 618 nm - 620 nm indicating synthesis of different porphyrins, such as the lipophylic Protoporphyrin IX (PpIX) and hydrophylic porphyrins (water soluble porphyrins, wsp). Of the 32 fluorescent bacterial strains, 18 produced wsp, often in combination with PpIX, and 5 produced solely wsp. These results clarify that ALA-based fluorescence diagnosis without consideration or suppression of bacteria fluorescence may lead to false-positive findings. It is necessary to suppress bacteria fluorescence with suitable antiseptics before starting the procedure. In this study, when specific antiseptic pre-treatment was performed bacterial associated fluorescence was significantly reduced.

  20. POSITIVE VERSUS NEGATIVE COMMUNICATION STRATEGIES IN TASK-BASED LEARNING

    Directory of Open Access Journals (Sweden)

    Siti Rohani

    2013-07-01

    Full Text Available This study aimed at describing how the implementation of Task Based Learning (TBL would shape or change students’ use of oral communication strategies. Students’ problems and strategies to solve the problems during the implementation of TBL were also explored. The study was a mixed method, employing both quantitative and qualitative analysis throughmulti-methods of questionnaire, interviews, focus group discussion, learning journals, and classroom observation. Participants were 26 second year students of the State Polytechnic of Malang. Data collection was conducted for one semester. Findingsshow linguistic and non-linguistic problems encountered by students during one-semester implementation of TBL. Students also performedincreased use of positive strategies but reduced use of negative strategies after the implementation of TBL.

  1. One-dimensional position sensitive detector based on photonic crystals

    International Nuclear Information System (INIS)

    Xi Feng; Qin Lan; Xue Lian; Duan Ying

    2013-01-01

    Position sensitive detectors (PSDs) are an important class of optical sensors which utilizes the lateral photovoltaic effect (LPVE). According to the operation principle of PSD, we demonstrate that LPVE can be enhanced by lengthening the lifetime of photo-generated carriers. A PSD based on photonic crystals (PCs) composed of MgF 2 and InP is proposed and designed. The transmittances of the defect PC and the reflectance of the perfect PC in the PSD are obtained with transfer matrix method. The theoretical research on the designed device shows that LPVE is enhanced by improving the transmittance of the defect PC and the reflectance of the perfect PC to lengthen the lifetime of photo-generated carriers. (authors)

  2. GPS-based satellite tracking system for precise positioning

    Science.gov (United States)

    Yunck, T. P.; Melbourne, W. G.; Thornton, C. L.

    1985-01-01

    NASA is developing a Global Positioning System (GPS) based measurement system to provide precise determination of earth satellite orbits, geodetic baselines, ionospheric electron content, and clock offsets between worldwide tracking sites. The system will employ variations on the differential GPS observing technique and will use a network of nine fixed ground terminals. Satellite applications will require either a GPS flight receiver or an on-board GPS beacon. Operation of the system for all but satellite tracking will begin by 1988. The first major satellite application will be a demonstration of decimeter accuracy in determining the altitude of TOPEX in the early 1990's. By then the system is expected to yield long-baseline accuracies of a few centimeters and instantaneous time synchronization to 1 ns.

  3. World wide web-based cytological analysis of atypical squamous cells cannot exclude high-grade intraepithelial lesions.

    Science.gov (United States)

    Washiya, Kiyotada; Takamizu, Ryuichi; Kumagai, Yukie; Himeji, Yukari; Kobayashi, Takako; Iwai, Muneo; Watanabe, Jun

    2012-01-01

    It has been reported that the low level of consistency of diagnosis of atypical squamous cells cannot exclude high-grade squamous intraepithelial lesions (ASC-H) in uterine cervical cancer screening using the Bethesda System, indicating the necessity of a large-scale survey. We presented cases cytologically judged as ASC-H on our website and invited our members to give their opinions regarding the diagnosis by voting online. The Web voting results were analyzed and ASC-H was cytologically investigated. Virtual slides of atypical cells in cytology preparations of 53 cases were prepared and presented on a website. ASC-H cases were divided into 42 cases sampled by brush scraping and 11 cases sampled by cotton swab scraping. Fifty-three cases cytologically judged as ASC-H were classified into benign and CIN2/3, and their patterns of arrangement of atypical cells and 8 cytological parameters were morphologically investigated. The frequency of ASC-H diagnosis in the Web votes was low: 29.2% for brush-scraped and 26.2% for cotton swab-scraped cases. Three-dimensionality, coarse chromatin and irregular nuclei were significantly different between high-grade squamous intraepithelial lesions and benign cases. Web-based surveys showed the difference of cytological findings between high-grade squamous intraepithelial lesions and benign cases. To increase interobserver consistency, it may be useful to share information online, which avoids geographical and temporal limitations. Copyright © 2012 S. Karger AG, Basel.

  4. Association between quantitative measures obtained using fluorescence-based methods and activity status of occlusal caries lesions in primary molars.

    Science.gov (United States)

    Novaes, Tatiane Fernandes; Reyes, Alessandra; Matos, Ronilza; Antunes-Pontes, Laura Regina; Marques, Renata Pereira de Samuel; Braga, Mariana Minatel; Diniz, Michele Baffi; Mendes, Fausto Medeiros

    2017-05-01

    Fluorescence-based methods (FBM) can add objectiveness to diagnosis strategy for caries. Few studies, however, have focused on the evaluation of caries activity. To evaluate the association between quantitative measures obtained with FBM, clinical parameters acquired from the patients, caries detection, and assessment of activity status in occlusal surfaces of primary molars. Six hundred and six teeth from 113 children (4-14 years) were evaluated. The presence of a biofilm, caries experience, and the number of active lesions were recorded. The teeth were assessed using FBM: DIAGNOdent pen (Lfpen) and Quantitative light-induced fluorescence (QLF). As reference standard, all teeth were evaluated using the ICDAS (International Caries Detection and Assessment System) associated with clinical activity assessments. Multilevel regressions compared the FBM values and evaluated the association between the FBM measures and clinical variables related to the caries activity. The measures from the FBM were higher in cavitated lesions. Only, ∆F values distinguished active and inactive lesions. The LFpen measures were higher in active lesions, at the cavitated threshold (56.95 ± 29.60). Following regression analyses, only the presence of visible biofilm on occlusal surfaces (adjusted prevalence ratio = 1.43) and ∆R values of the teeth (adjusted prevalence ratio = 1.02) were associated with caries activity. Some quantitative measures from FBM parameters are associated with caries activity evaluation, which is similar to the clinical evaluation of the presence of visible biofilm. © 2016 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Identification and Map-Based Cloning of the Light-Induced Lesion Mimic Mutant 1 (LIL1) Gene in Rice.

    Science.gov (United States)

    Zhou, Qian; Zhang, Zhifei; Liu, Tiantian; Gao, Bida; Xiong, Xingyao

    2017-01-01

    The hypersensitive response (HR) is a mechanism by which plants prevent the spread of pathogen. Despite extensive study, the molecular mechanisms underlying HR remain poorly understood. Lesion mimic mutants (LMMs), such as LIL1 that was identified in an ethylmethane sulfonate mutagenized population of Indica rice ( Oryza sativa L. ssp. Indica ) 93-11, can be used to study the HR. Under natural field conditions, the leaves of LIL1 mutant plants exhibited light-induced, small, rust-red lesions that first appeared at the leaf tips and subsequently expanded throughout the entire leaf blade to the leaf sheath. Histochemical staining indicated that LIL1 lesions displayed an abnormal accumulation of reactive oxygen species (ROS) and resulted from programmed cell death (PCD). The LIL1 mutants also displayed increased expression of defense-related genes and enhanced resistance to rice blast fungus ( Magnaporthe grisea ). Genetic analysis showed that mutation of LIL1 created a semi-dominant allele. Using 1,758 individuals in the F 2 population, LIL1 was mapped in a 222.3 kb region on the long arm of chromosome 7. That contains 12 predicted open reading frames (ORFs). Sequence analysis of these 12 candidate genes revealed a G to A base substitution in the fourth exon of LOC_Os07g30510, a putative cysteine-rich receptor-like kinase (CRK), which led to an amino acid change (Val 429 to Ile) in the LIL1 protein. Comparison of the transcript accumulation of the 12 candidate genes between LIL1 and 93-11 revealed that LOC_Os07g30510 was up-regulated significantly in LIL1 . Overexpression of the LOC_Os07g30510 gene from LIL1 induced a LIL1 -like lesion phenotype in Nipponbare. Thus, LIL1 is a novel LMM in rice that will facilitate the further study of the molecular mechanisms of HR and the rice blast resistance.

  6. HISTOPATHOLOGICAL PROFILE OF LIVER LESIONS IN AUTOPSY EXAMINATION- A HOSPITAL-BASED STUDY

    Directory of Open Access Journals (Sweden)

    Ratan Konjengbam

    2017-06-01

    Full Text Available BACKGROUND Liver is the main site of various primary and secondary diseases including variety of external agents. Most of the chronic liver diseases remained asymptomatic even in the late stage. In apparently healthy persons, many liver lesions are detected incidentally following a postmortem examination. MATERIALS AND METHODS The present study was done for a period of 5 years in a tertiary hospital to evaluate the histopathological profile of liver specimen in autopsy examination. Haematoxylin and Eosin sections of liver specimen were studied. A total of 352 samples were evaluated with male predominates the female sex in the ratio of 5.2:1. RESULTS The most common lesion was fatty liver (19% followed by cirrhosis (11.8%, venous congestion (11.5%, portal triaditis (10.9%, chronic hepatitis (6.2%, granulomatous hepatitis (2.1%, autolysis (16% and others (0.96%. Liver finding was normal in 14% of the cases. CONCLUSION Silent liver diseases are a quite regular finding in autopsy cases and thereby may implicate a common occurrence in general population. Autopsy examination of liver is a must for detection of silent liver diseases like fatty change, cirrhosis and chronic hepatitis.

  7. IS IT NECESSARY TO EXCISE ALL BREAST LESIONS? EXPERIENCE FROM A UNIVERSITY-BASED BREAST UNIT

    Directory of Open Access Journals (Sweden)

    YIP CH

    2009-01-01

    Full Text Available Background: Breast cancer is becoming more important in Asia since it affect the younger age group. Question arises whether it is safe for breast lesions to be left in-situ if all the elements in triple assessment are benign. The aim of this study is to audit all the excision biopsies of breast lumps done in the University Malaya Medical Centre (UMMC, to review the association of age with the type of pathological finding and to evaluate the rate of carcinoma in these biopsies. Methods: We conducted a retrospective study of all women who had excision biopsy of a breast lump in the University Malaya Medical Centre from January 2005 to December 2006. All patients with malignant preoperative biopsies were excluded. Results: Of 717 lesions in 664 patients, 459 (64% were fibroadenoma, 114 (15.9% were fibrocystic disease, 20 (2.8% were phylloides tumour, 27 (3.8% were papilloma, 59 (8.2% were malignant and 38 (5.3% were of other pathology. Of the 717 open biopsies, 449 (62.6% had fine-needle aspiration cytology (FNAC, 31 (4.3% had core needle biopsy (CNB, while 14 (2.0% had both FNAC and CNB done prior to excision biopsy. 251 (35% had neither FNAC nor CNB. The incidence of fibroadenoma decreased with increasing age and the incidence of fibrocystic changes and papilloma increased with increasing age. There was no association of age with phylloides tumour. The incidence of unexpected malignancy increased with increasing age. The incidence rates were 0.3%, 4.5%, 19.4%, 29.7% and 29.6% for the age group below 30, 30-39, 40-49, 50-59 and above 60 years of age respectively. Of the 59 malignant lesions, FNAC was performed on 47 (79.7% and CNB on 16 (27.1%. 9 had both FNAC and CNB and 3 had neither FNAC nor CNB. Out of the 56 lesions where FNAC/CNB were done, 23 (41.1% were reported as benign, 20 (35.7% as suspicious, 4 (7.1% as atypical, 5 (8.9% as inadequate, 2 (3.6% as equivocal and 2 (3.6% as lymphoid lesions. Out of the 23 prior biopsies reported as

  8. Development of a Support Vector Machine - Based Image Analysis System for Focal Liver Lesions Classification in Magnetic Resonance Images

    International Nuclear Information System (INIS)

    Gatos, I; Tsantis, S; Kagadis, G; Karamesini, M; Skouroliakou, A

    2015-01-01

    Purpose: The design and implementation of a computer-based image analysis system employing the support vector machine (SVM) classifier system for the classification of Focal Liver Lesions (FLLs) on routine non-enhanced, T2-weighted Magnetic Resonance (MR) images. Materials and Methods: The study comprised 92 patients; each one of them has undergone MRI performed on a Magnetom Concerto (Siemens). Typical signs on dynamic contrast-enhanced MRI and biopsies were employed towards a three class categorization of the 92 cases: 40-benign FLLs, 25-Hepatocellular Carcinomas (HCC) within Cirrhotic liver parenchyma and 27-liver metastases from Non-Cirrhotic liver. Prior to FLLs classification an automated lesion segmentation algorithm based on Marcov Random Fields was employed in order to acquire each FLL Region of Interest. 42 texture features derived from the gray-level histogram, co-occurrence and run-length matrices and 12 morphological features were obtained from each lesion. Stepwise multi-linear regression analysis was utilized to avoid feature redundancy leading to a feature subset that fed the multiclass SVM classifier designed for lesion classification. SVM System evaluation was performed by means of leave-one-out method and ROC analysis. Results: Maximum accuracy for all three classes (90.0%) was obtained by means of the Radial Basis Kernel Function and three textural features (Inverse- Different-Moment, Sum-Variance and Long-Run-Emphasis) that describe lesion's contrast, variability and shape complexity. Sensitivity values for the three classes were 92.5%, 81.5% and 96.2% respectively, whereas specificity values were 94.2%, 95.3% and 95.5%. The AUC value achieved for the selected subset was 0.89 with 0.81 - 0.94 confidence interval. Conclusion: The proposed SVM system exhibit promising results that could be utilized as a second opinion tool to the radiologist in order to decrease the time/cost of diagnosis and the need for patients to undergo invasive

  9. Self-Inflicted Lesions in Dermatology: A Management and Therapeutic Approach - A Position Paper From the European Society for Dermatology and Psychiatry

    NARCIS (Netherlands)

    Tomas-Aragones, Lucia; Consoli, Silla M.; Consoli, Sylvie G.; Poot, Francoise; Taube, Klaus-Michael; Linder, M. Dennis; Jemec, Gregor B. E.; Szepietowski, Jacek C.; de Korte, John; Lvov, Andrey; Gieler, Uwe

    2017-01-01

    The classification of self-inflicted skin lesions proposed by the European Society for Dermatology and Psychiatry (ESDaP) group generated questions with regard to specific treatments that could be recommended for such cases. The therapeutic guidelines in the current paper integrate new

  10. Success or failure of vaccination for HPV16-positive vulvar lesions correlates with kinetics and phenotype of induced T-cell responses

    NARCIS (Netherlands)

    Welters, Marij J. P.; Kenter, Gemma G.; de Vos van Steenwijk, Peggy J.; Löwik, Margriet J. G.; Berends-van der Meer, Dorien M. A.; Essahsah, Farah; Stynenbosch, Linda F. M.; Vloon, Annelies P. G.; Ramwadhdoebe, Tamara H.; Piersma, Sytse J.; van der Hulst, Jeanette M.; Valentijn, A. Rob P. M.; Fathers, Lorraine M.; Drijfhout, Jan W.; Franken, Kees L. M. C.; Oostendorp, Jaap; Fleuren, Gert Jan; Melief, Cornelis J. M.; van der Burg, Sjoerd H.

    2010-01-01

    One half of a group of 20 patients with human papillomavirus type 16 (HPV16)-induced vulvar intraepithelial neoplasia grade 3 displayed a complete regression (CR) after therapeutic vaccination with HPV16 E6/E7 synthetic long peptides. Patients with relatively larger lesions generally did not display

  11. Self-inflicted lesions in dermatology: terminology and classification--a position paper from the European Society for Dermatology and Psychiatry (ESDaP)

    NARCIS (Netherlands)

    Gieler, Uwe; Consoli, Sylvie G.; Tomás-Aragones, Lucía; Linder, Dennis M.; Jemec, Gregor B. E.; Poot, Francoise; Szepietowski, Jacek C.; de Korte, John; Taube, Klaus-Michael; Lvov, Andrey; Consoli, Silla M.

    2013-01-01

    The terminology, classification, diagnosis and treatment of self-inflicted dermatological lesions are subjects of open debate. The present study is the result of various meetings of a task force of dermatologists, psychiatrists and psychologists, all active in the field of psychodermatology, aimed

  12. International investigation of breast MRI: results of a multicentre study (11 sites) concerning diagnostic parameters for contrast-enhanced MRI based on 519 histopathologically correlated lesions

    International Nuclear Information System (INIS)

    Heywang-Koebrunner, S.H.; Bick, U.; Bradley, W.G. Jr.; Bone, B.; Casselman, J.; Coulthard, A.; Fischer, U.; Mueller-Schimpfle, M.; Oellinger, H.; Patt, R.; Teubner, J.; Friedrich, M.; Newstead, G.; Holland, R.; Schauer, A.; Sickles, E.A.; Tabar, L.; Waisman, J.; Wernecke, K.D.

    2001-01-01

    A multicentre study was undertaken to provide fundamentals for improved standardization and optimized interpretation guidelines of dynamic contrast-enhanced MRI. Only patients scheduled for biopsy of a clinical or imaging abnormality were included. They underwent standardized dynamic MRI on Siemens 1.0 (163 valid lesions ≥ 5 mm) or 1.5 T (395 valid lesions ≥ 5 mm) using 3D fast low-angle shot (FLASH; 87 s) before and five times after standardized bolus of 0.2 mmol Gd-DTPA/kg. One-Tesla and 1.5 T data were analysed separately using a discriminant analysis. Only histologically correlated lesions entered the statistical evaluation. Histopathology and imaging were correlated in retrospect and in open. The best results were achieved by combining up to five wash-in or wash-out parameters. Different weighting of false-negative vs false-positive calls allowed formulation of a statistically based interpretation scheme yielding optimized rules for the highest possible sensitivity (specificity 30 %), for moderate (50 %) or high (64-71 %) specificity. The sensitivities obtained at the above specificity levels were better at 1.0 T (98, 97, or 96 %) than at 1.5 T (96, 93, 86 %). Using a widely available standardized MR technique definition of statistically founded interpretation rules is possible. Choice of an optimum interpretation rule may vary with the clinical question. Prospective testing remains necessary. Differences of 1.0 and 1.5 T are not statistically significant but may be due to pulse sequences (orig.)

  13. International investigation of breast MRI: results of a multicentre study (11 sites) concerning diagnostic parameters for contrast-enhanced MRI based on 519 histopathologically correlated lesions

    Energy Technology Data Exchange (ETDEWEB)

    Heywang-Koebrunner, S.H. [Dept. of Diagnostic Radiology, Univ. Hospital Halle (Germany); Bick, U. [Dept. of Diagnostic Radiology, Westphalian Wilhelms Univ., Muenster (Germany); Bradley, W.G. Jr. [Memorial Medical Center, Long Beach, CA (United States); Bone, B. [Dept. of Diagnostic Radiology, Huddinge Univ., Stockholm (Sweden); Casselman, J. [Dept. of Diagnostic Radiology, Brugge (Belgium); Coulthard, A. [Dept. of Diagnostic Radiology, Royal Victoria Infirmary, Newcastle (United Kingdom); Fischer, U. [Dept. of Diagnostic Radiology, Georg August University, Goettingen (Germany); Mueller-Schimpfle, M. [Dept. of Diagnostic Radiology, Eberhard Karls University, Tuebingen (Germany); Oellinger, H. [Dept. of Diagnostic Radiology, Rudolph Virchow Univ. Clinic, Berlin (Germany); Patt, R. [Dept. of Diagnostic Radiology, Georgetown Univ., Washington, DC (United States); Teubner, J. [Dept. of Diagnostic Radiology, Mannheim Clinic, Heidelberg Univ. (Germany); Friedrich, M. [Dept. of Diagnostic Radiology, Urban Hospital, Berlin (Germany); Newstead, G. [Faculty Practice Radiology, New York Univ., NY (United States); Holland, R. [Dept. of Pathology, Univ. Hospital Nijmegen (Netherlands); Schauer, A. [Dept. of Pathology, Georg August Univ., Goettingen (Germany); Sickles, E.A. [Dept. of Radiology, University of California, San Francisco (United States); Tabar, L. [Falun Central Hospital, Falun (Sweden); Waisman, J. [Dept. of Pathology, New York University, NY (United States); Wernecke, K.D. [Inst. of Medical Biometrics, University Charite, Berlin (Germany)

    2001-04-01

    A multicentre study was undertaken to provide fundamentals for improved standardization and optimized interpretation guidelines of dynamic contrast-enhanced MRI. Only patients scheduled for biopsy of a clinical or imaging abnormality were included. They underwent standardized dynamic MRI on Siemens 1.0 (163 valid lesions {>=} 5 mm) or 1.5 T (395 valid lesions {>=} 5 mm) using 3D fast low-angle shot (FLASH; 87 s) before and five times after standardized bolus of 0.2 mmol Gd-DTPA/kg. One-Tesla and 1.5 T data were analysed separately using a discriminant analysis. Only histologically correlated lesions entered the statistical evaluation. Histopathology and imaging were correlated in retrospect and in open. The best results were achieved by combining up to five wash-in or wash-out parameters. Different weighting of false-negative vs false-positive calls allowed formulation of a statistically based interpretation scheme yielding optimized rules for the highest possible sensitivity (specificity 30 %), for moderate (50 %) or high (64-71 %) specificity. The sensitivities obtained at the above specificity levels were better at 1.0 T (98, 97, or 96 %) than at 1.5 T (96, 93, 86 %). Using a widely available standardized MR technique definition of statistically founded interpretation rules is possible. Choice of an optimum interpretation rule may vary with the clinical question. Prospective testing remains necessary. Differences of 1.0 and 1.5 T are not statistically significant but may be due to pulse sequences (orig.)

  14. Regularization of positive definite matrix fields based on multiplicative calculus

    NARCIS (Netherlands)

    Florack, L.M.J.; Bruckstein, A.M.; Haar Romeny, ter B.M.; Bronstein, A.M.; Bronstein, M.M.

    2012-01-01

    Multiplicative calculus provides a natural framework in problems involving positive images and positivity preserving operators. In increasingly important, complex imaging frameworks, such as diffusion tensor imaging, it complements standard calculus in a nontrivial way. The purpose of this article

  15. A novel method based on learning automata for automatic lesion detection in breast magnetic resonance imaging.

    Science.gov (United States)

    Salehi, Leila; Azmi, Reza

    2014-07-01

    Breast cancer continues to be a significant public health problem in the world. Early detection is the key for improving breast cancer prognosis. In this way, magnetic resonance imaging (MRI) is emerging as a powerful tool for the detection of breast cancer. Breast MRI presently has two major challenges. First, its specificity is relatively poor, and it detects many false positives (FPs). Second, the method involves acquiring several high-resolution image volumes before, during, and after the injection of a contrast agent. The large volume of data makes the task of interpretation by the radiologist both complex and time-consuming. These challenges have led to the development of the computer-aided detection systems to improve the efficiency and accuracy of the interpretation process. Detection of suspicious regions of interests (ROIs) is a critical preprocessing step in dynamic contrast-enhanced (DCE)-MRI data evaluation. In this regard, this paper introduces a new automatic method to detect the suspicious ROIs for breast DCE-MRI based on region growing. The results indicate that the proposed method is thoroughly able to identify suspicious regions (accuracy of 75.39 ± 3.37 on PIDER breast MRI dataset). Furthermore, the FP per image in this method is averagely 7.92, which shows considerable improvement comparing to other methods like ROI hunter.

  16. An effective approach of lesion segmentation within the breast ultrasound image based on the cellular automata principle.

    Science.gov (United States)

    Liu, Yan; Cheng, H D; Huang, Jianhua; Zhang, Yingtao; Tang, Xianglong

    2012-10-01

    In this paper, a novel lesion segmentation within breast ultrasound (BUS) image based on the cellular automata principle is proposed. Its energy transition function is formulated based on global image information difference and local image information difference using different energy transfer strategies. First, an energy decrease strategy is used for modeling the spatial relation information of pixels. For modeling global image information difference, a seed information comparison function is developed using an energy preserve strategy. Then, a texture information comparison function is proposed for considering local image difference in different regions, which is helpful for handling blurry boundaries. Moreover, two neighborhood systems (von Neumann and Moore neighborhood systems) are integrated as the evolution environment, and a similarity-based criterion is used for suppressing noise and reducing computation complexity. The proposed method was applied to 205 clinical BUS images for studying its characteristic and functionality, and several overlapping area error metrics and statistical evaluation methods are utilized for evaluating its performance. The experimental results demonstrate that the proposed method can handle BUS images with blurry boundaries and low contrast well and can segment breast lesions accurately and effectively.

  17. Transsphenoidal Approach in Endoscopic Endonasal Surgery for Skull Base Lesions: What Radiologists and Surgeons Need to Know.

    Science.gov (United States)

    García-Garrigós, Elena; Arenas-Jiménez, Juan José; Monjas-Cánovas, Irene; Abarca-Olivas, Javier; Cortés-Vela, Jesús Julián; De La Hoz-Rosa, Javier; Guirau-Rubio, Maria Dolores

    2015-01-01

    In the last 2 decades, endoscopic endonasal transsphenoidal surgery has become the most popular choice of neurosurgeons and otolaryngologists to treat lesions of the skull base, with minimal invasiveness, lower incidence of complications, and lower morbidity and mortality rates compared with traditional approaches. The transsphenoidal route is the surgical approach of choice for most sellar tumors because of the relationship of the sphenoid bone to the nasal cavity below and the pituitary gland above. More recently, extended approaches have expanded the indications for transsphenoidal surgery by using different corridors leading to specific target areas, from the crista galli to the spinomedullary junction. Computer-assisted surgery is an evolving technology that allows real-time anatomic navigation during endoscopic surgery by linking preoperative triplanar radiologic images and intraoperative endoscopic views, thus helping the surgeon avoid damage to vital structures. Preoperative computed tomography is the preferred modality to show bone landmarks and vascular structures. Radiologists play an important role in surgical planning by reporting extension of sphenoid pneumatization, recesses and septations of the sinus, and other relevant anatomic variants. Radiologists should understand the relationships of the sphenoid bone and skull base structures, anatomic variants, and image-guided neuronavigation techniques to prevent surgical complications and allow effective treatment of skull base lesions with the endoscopic endonasal transsphenoidal approach. ©RSNA, 2015.

  18. A Pseudorange Measurement Scheme Based on Snapshot for Base Station Positioning Receivers.

    Science.gov (United States)

    Mo, Jun; Deng, Zhongliang; Jia, Buyun; Bian, Xinmei

    2017-12-01

    Digital multimedia broadcasting signal is promised to be a wireless positioning signal. This paper mainly studies a multimedia broadcasting technology, named China mobile multimedia broadcasting (CMMB), in the context of positioning. Theoretical and practical analysis on the CMMB signal suggests that the existing CMMB signal does not have the meter positioning capability. So, the CMMB system has been modified to achieve meter positioning capability by multiplexing the CMMB signal and pseudo codes in the same frequency band. The time difference of arrival (TDOA) estimation method is used in base station positioning receivers. Due to the influence of a complex fading channel and the limited bandwidth of receivers, the regular tracking method based on pseudo code ranging is difficult to provide continuous and accurate TDOA estimations. A pseudorange measurement scheme based on snapshot is proposed to solve the problem. This algorithm extracts the TDOA estimation from the stored signal fragments, and utilizes the Taylor expansion of the autocorrelation function to improve the TDOA estimation accuracy. Monte Carlo simulations and real data tests show that the proposed algorithm can significantly reduce the TDOA estimation error for base station positioning receivers, and then the modified CMMB system achieves meter positioning accuracy.

  19. Reliable Freestanding Position-Based Routing in Highway Scenarios

    Science.gov (United States)

    Galaviz-Mosqueda, Gabriel A.; Aquino-Santos, Raúl; Villarreal-Reyes, Salvador; Rivera-Rodríguez, Raúl; Villaseñor-González, Luis; Edwards, Arthur

    2012-01-01

    Vehicular Ad Hoc Networks (VANETs) are considered by car manufacturers and the research community as the enabling technology to radically improve the safety, efficiency and comfort of everyday driving. However, before VANET technology can fulfill all its expected potential, several difficulties must be addressed. One key issue arising when working with VANETs is the complexity of the networking protocols compared to those used by traditional infrastructure networks. Therefore, proper design of the routing strategy becomes a main issue for the effective deployment of VANETs. In this paper, a reliable freestanding position-based routing algorithm (FPBR) for highway scenarios is proposed. For this scenario, several important issues such as the high mobility of vehicles and the propagation conditions may affect the performance of the routing strategy. These constraints have only been partially addressed in previous proposals. In contrast, the design approach used for developing FPBR considered the constraints imposed by a highway scenario and implements mechanisms to overcome them. FPBR performance is compared to one of the leading protocols for highway scenarios. Performance metrics show that FPBR yields similar results when considering freespace propagation conditions, and outperforms the leading protocol when considering a realistic highway path loss model. PMID:23202159

  20. A cage position monitor based on magnetically striped rope

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, V M

    1978-01-01

    Following the winding disaster at Markham Colliery in July 1973 recommendations to monitor the position of the cage directly at all times throughout the winding cycle, and to provide a system of communication with persons in the conveyance were made. The system adopted by MRDE was the 'magnetically striped rope'. An experimental system was installed at Maltby Colliery, South Yorkshire, and has been working successfully for well over a year. Magnetic marking of a hoist or guide rope can be carried out using permanent magnets but a much more convenient method has been devised using a pulsed electromagnet sliding on the rope. Detection is achieved by two static magnetic sensors spaced to give quadrature output. By processing the signals and using an up/down counter it is possible to sense the direction of movement and the distance travelled by the cage from a given datum. The information can be further processed to indicate velocity, overspeed and overwind, and when referenced to drum revolutions may be used to monitor rope slip in friction winders or slack rope in drum winders. When the guide rope is magnetically marked and sensed, the information must be transmitted from the cage to the surface. Such a data communication link, developed by MRDE, also provides a base for a general shaft communication system.

  1. The Prohibitive Link between Position-based Routing and Planarity

    Directory of Open Access Journals (Sweden)

    David Cairns

    2013-12-01

    Full Text Available Position-based routing is touted as an ideal routing strategy for resource-constrained wireless networks. One persistent barrier to adoption is due to its recovery phase, where messages are forwarded according to leftor right-hand rule (LHR. This is often referred to as face-routing. In this paper we investigate the limits of LHR with respect to planarity.We show that the gap between non-planarity and successful delivery is a single link within a single configuration. Our work begins with an analysis to enumerate all node configurations that cause intersections in the unit-disc graph. We find that left-hand rule is able to recover from all but a single case, the ‘umbrella’ configuration so named for its appearance. We use this information to propose the Prohibitive Link Detection Protocol (PLDP that can guarantee delivery over non-planar graphs using standard face-routing techniques. As the name implies, the protocol detects and circumvents the ‘bad’ links that hamper LHR. The goal of this work is to maintain routing guarantees while disturbing the network graph as little as possible. In doing so, a new starting point emerges from which to build rich distributed protocols in the spirit of CLDP and GDSTR.

  2. Joint approach based on clinical and imaging features to distinguish non-neoplastic from neoplastic pituitary stalk lesions.

    Directory of Open Access Journals (Sweden)

    Ji Ye Lee

    Full Text Available Distinguishing non-neoplastic pituitary stalk lesions (non-NPSLs from neoplastic pituitary stalk lesions (NPSLs is a major concern in guiding treatment for a thickened pituitary stalk. Our study aimed to aid provide preoperative diagnostic assistance by combining clinical and magnetic resonance imaging (MRI findings to distinguish non-NPSLs from NPSLs.We recruited 158 patients with thickened pituitary stalk lesions visible on MRI. Laboratory findings included hypopituitarism, diabetes insipidus (DI, and hyperprolactinemia. MR images were assessed for anterior-posterior thickness (mm, diffuse pituitary stalk thickening, cystic changes, a high T1 signal, and glandular or extrasellar involvement. A diagnostic model was developed using a recursive partitioning logistic regression analysis. The model was validated in an independent dataset comprising 63 patients, and its diagnostic performance was compared with that of the original radiological reports.A univariate analysis found significant associations of DI (P = 0.006, absence of extrasellar involvement (P = 0.002, and lower stalk thickness (P = 0.031 with non-NPSLs. A diagnostic model was created using the following parameters (in order of priority: 1 lack of extrasellar involvement, 2 stalk thickness < 5.3 mm, and 3 presence of DI. The diagnostic performance (area under the curve; AUC of this model in the independent set was 0.813, representing a significant improvement over the original radiological reports (AUC: 0.713, P = 0.029.The joint diagnostic approach based on clinical and imaging-based factors robustly distinguished non-NPSLs from NPSLs. This approach could guide treatment strategies and prevent unnecessary surgery in patients with non-NPSL.

  3. Local CD34-positive capillaries decrease in mouse models of kidney disease associating with the severity of glomerular and tubulointerstitial lesions.

    Science.gov (United States)

    Masum, Md Abdul; Ichii, Osamu; Elewa, Yaser Hosny Ali; Nakamura, Teppei; Kon, Yasuhiro

    2017-09-04

    The renal vasculature plays important roles in both homeostasis and pathology. In this study, we examined pathological changes in the renal microvascular in mouse models of kidney diseases. Glomerular lesions (GLs) in autoimmune disease-prone male BXSB/MpJ-Yaa (Yaa) mice and tubulointerstitial lesions (TILs) in male C57BL/6 mice subjected to unilateral ureteral obstruction (UUO) for 7 days were studied. Collected kidneys were examined using histopathological techniques. A nonparametric Mann-Whitney U test (P < 0.05) was performed to compare healthy controls and the experimental mice. The Kruskal-Wallis test was used to compare three or more groups, and multiple comparisons were performed using Scheffe's method when significant differences were observed (P < 0.05). Yaa mice developed severe autoimmune glomerulonephritis, and the number of CD34 + glomerular capillaries decreased significantly in GLs compared to that in control mice. However, UUO-treated mice showed severe TILs only, and CD34 + tubulointerstitial capillaries were decreased significantly in TILs with the progression of tubulointerstitial fibrosis compared to those in untreated control kidneys. Infiltrations of B-cells, T-cells, and macrophages increased significantly in the respective lesions of both disease models (P < 0.05). In observations of vascular corrosion casts by scanning electron microscopy and of microfil rubber-perfused thick kidney sections by fluorescence microscopy, segmental absences of capillaries were observed in the GLs and TILs of Yaa and UUO-treated mice, respectively. Further, transmission electron microscopy revealed capillary endothelial injury in the respective lesions of both models. The numbers of CD34 + glomerular and tubulointerstitial capillaries were negatively correlated with all examined parameters in GLs (P < 0.05) and TILs (P < 0.01), respectively. From the analysis of mouse models, we identified inverse pathological correlations between the number of

  4. Precision resection of intra-axial CNS lesions by CT-based stereotactic craniotomy and computer monitored CO2 laser

    International Nuclear Information System (INIS)

    Kelly, P.J.; Kall, B.; Goerss, S.; Alker, G.J. Jr.

    1983-01-01

    This report describes an open stereotactic technique by which a tumour volume reconstructed in stereotactic space from CT data is removed by stereotactic CO 2 laser vaporization. The position of the laser beam in relation to the tumour outlines is monitored by computer and displayed to the surgeon on a graphics display terminal in the operating room. Twenty-six (26) of these procedures have been performed on twenty-four (24) patients with deep-seated intra-axial neoplasms (23) and arteriovenous malformation. Post-operative CT scanning revealed no evidence of contrast enhancing lesions in nineteen (19) patients while a small amount of residual tumour was noted in five (5) patients post-operatively. This method has proven itself valuable for maintaining three-dimensional surgical orientation for the resection of intra-axial neoplasms from neurologically important areas. (Author)

  5. Predicting Drug-Target Interactions Based on Small Positive Samples.

    Science.gov (United States)

    Hu, Pengwei; Chan, Keith C C; Hu, Yanxing

    2018-01-01

    A basic task in drug discovery is to find new medication in the form of candidate compounds that act on a target protein. In other words, a drug has to interact with a target and such drug-target interaction (DTI) is not expected to be random. Significant and interesting patterns are expected to be hidden in them. If these patterns can be discovered, new drugs are expected to be more easily discoverable. Currently, a number of computational methods have been proposed to predict DTIs based on their similarity. However, such as approach does not allow biochemical features to be directly considered. As a result, some methods have been proposed to try to discover patterns in physicochemical interactions. Since the number of potential negative DTIs are very high both in absolute terms and in comparison to that of the known ones, these methods are rather computationally expensive and they can only rely on subsets, rather than the full set, of negative DTIs for training and validation. As there is always a relatively high chance for negative DTIs to be falsely identified and as only partial subset of such DTIs is considered, existing approaches can be further improved to better predict DTIs. In this paper, we present a novel approach, called ODT (one class drug target interaction prediction), for such purpose. One main task of ODT is to discover association patterns between interacting drugs and proteins from the chemical structure of the former and the protein sequence network of the latter. ODT does so in two phases. First, the DTI-network is transformed to a representation by structural properties. Second, it applies a oneclass classification algorithm to build a prediction model based only on known positive interactions. We compared the best AUROC scores of the ODT with several state-of-art approaches on Gold standard data. The prediction accuracy of the ODT is superior in comparison with all the other methods at GPCRs dataset and Ion channels dataset. Performance

  6. Evidence-based treatments for the asymptomatic HIV- positive ...

    African Journals Online (AJOL)

    banzi

    ty of the women attending antenatal clin- ics are healthy and therefore ... a decrease in the patient's risk of falling ill from opportunistic .... 10% risk in those who are tuberculin-. n e g a t i v e . In summary. • There is grade-A evidence that. HIV-positive patients who are tuberculin skin-positive benefit from anti-TB prophylaxis.

  7. MWA Versus RFA for Perivascular and Peribiliary CRLM: A Retrospective Patient- and Lesion-Based Analysis of Two Historical Cohorts

    Energy Technology Data Exchange (ETDEWEB)

    Tilborg, Aukje A. J. M. van, E-mail: a.vantilborg@vumc.nl; Scheffer, Hester J.; Jong, Marcus C. de; Vroomen, Laurien G. P. H. [VU University Medical Centre, Department of Radiology and Nuclear Medicine (Netherlands); Nielsen, Karin [VU University Medical Centre, Department of Surgical Oncology (Netherlands); Kuijk, Cornelis van [VU University Medical Centre, Department of Radiology and Nuclear Medicine (Netherlands); Tol, Petrousjka M. P. van den [VU University Medical Centre, Department of Surgical Oncology (Netherlands); Meijerink, Martijn R. [VU University Medical Centre, Department of Radiology and Nuclear Medicine (Netherlands)

    2016-10-15

    PurposeTo retrospectively analyse the safety and efficacy of radiofrequency ablation (RFA) versus microwave ablation (MWA) in the treatment of unresectable colorectal liver metastases (CRLM) in proximity to large vessels and/or major bile ducts.Method and MaterialsA database search was performed to include patients with unresectable histologically proven and/or {sup 18}F–FDG–PET avid CRLM who were treated with RFA or MWA between January 2001 and September 2014 in a single centre. All lesions that were considered to have a peribiliary and/or perivascular location were included. Univariate logistic regression analysis was performed to assess the distribution of patient, tumour and procedure characteristics. Multivariate logistic regression was used to correct for potential confounders.ResultsTwo hundred and forty-three patients with 774 unresectable CRLM were ablated. One hundred and twenty-two patients (78 males; 44 females) had at least one perivascular or peribiliary lesion (n = 199). Primary efficacy rate of RFA was superior to MWA after 3 and 12 months of follow-up (P = 0.010 and P = 0.022); however, after multivariate analysis this difference was non-significant at 12 months (P = 0.078) and vanished after repeat ablations (P = 0.39). More CTCAE grade III complications occurred after MWA versus RFA (18.8 vs. 7.9 %; P = 0.094); biliary complications were especially common after peribiliary MWA (P = 0.002).ConclusionFor perivascular CRLM, RFA and MWA are both safe treatment options that appear equally effective. For peribiliary CRLM, MWA has a higher complication rate than RFA, with similar efficacy. Based on these results, it is advised to use RFA for lesions in the proximity of major bile ducts.

  8. MWA Versus RFA for Perivascular and Peribiliary CRLM: A Retrospective Patient- and Lesion-Based Analysis of Two Historical Cohorts

    International Nuclear Information System (INIS)

    Tilborg, Aukje A. J. M. van; Scheffer, Hester J.; Jong, Marcus C. de; Vroomen, Laurien G. P. H.; Nielsen, Karin; Kuijk, Cornelis van; Tol, Petrousjka M. P. van den; Meijerink, Martijn R.

    2016-01-01

    PurposeTo retrospectively analyse the safety and efficacy of radiofrequency ablation (RFA) versus microwave ablation (MWA) in the treatment of unresectable colorectal liver metastases (CRLM) in proximity to large vessels and/or major bile ducts.Method and MaterialsA database search was performed to include patients with unresectable histologically proven and/or "1"8F–FDG–PET avid CRLM who were treated with RFA or MWA between January 2001 and September 2014 in a single centre. All lesions that were considered to have a peribiliary and/or perivascular location were included. Univariate logistic regression analysis was performed to assess the distribution of patient, tumour and procedure characteristics. Multivariate logistic regression was used to correct for potential confounders.ResultsTwo hundred and forty-three patients with 774 unresectable CRLM were ablated. One hundred and twenty-two patients (78 males; 44 females) had at least one perivascular or peribiliary lesion (n = 199). Primary efficacy rate of RFA was superior to MWA after 3 and 12 months of follow-up (P = 0.010 and P = 0.022); however, after multivariate analysis this difference was non-significant at 12 months (P = 0.078) and vanished after repeat ablations (P = 0.39). More CTCAE grade III complications occurred after MWA versus RFA (18.8 vs. 7.9 %; P = 0.094); biliary complications were especially common after peribiliary MWA (P = 0.002).ConclusionFor perivascular CRLM, RFA and MWA are both safe treatment options that appear equally effective. For peribiliary CRLM, MWA has a higher complication rate than RFA, with similar efficacy. Based on these results, it is advised to use RFA for lesions in the proximity of major bile ducts.

  9. The learning curve for narrow-band imaging in the diagnosis of precancerous gastric lesions by using Web-based video.

    Science.gov (United States)

    Dias-Silva, Diogo; Pimentel-Nunes, Pedro; Magalhães, Joana; Magalhães, Ricardo; Veloso, Nuno; Ferreira, Carlos; Figueiredo, Pedro; Moutinho, Pedro; Dinis-Ribeiro, Mário

    2014-06-01

    A simplified narrow-band imaging (NBI) endoscopy classification of gastric precancerous and cancerous lesions was derived and validated in a multicenter study. This classification comes with the need for dissemination through adequate training. To address the learning curve of this classification by endoscopists with differing expertise and to assess the feasibility of a YouTube-based learning program to disseminate it. Prospective study. Five centers. Six gastroenterologists (3 trainees, 3 fully trained endoscopists [FTs]). Twenty tests provided through a Web-based program containing 10 randomly ordered NBI videos of gastric mucosa were taken. Feedback was sent 7 days after every test submission. Measures of accuracy of the NBI classification throughout the time. From the first to the last 50 videos, a learning curve was observed with a 10% increase in global accuracy, for both trainees (from 64% to 74%) and FTs (from 56% to 65%). After 200 videos, sensitivity and specificity of 80% and higher for intestinal metaplasia were observed in half the participants, and a specificity for dysplasia greater than 95%, along with a relevant likelihood ratio for a positive result of 7 to 28 and likelihood ratio for a negative result of 0.21 to 0.82, were achieved by all of the participants. No constant learning curve was observed for the identification of Helicobacter pylori gastritis and sensitivity to dysplasia. The trainees had better results in all of the parameters, except specificity for dysplasia, compared with the FTs. Globally, participants agreed that the program's structure was adequate, except on the feedback, which should have consisted of a more detailed explanation of each answer. No formal sample size estimate. A Web-based learning program could be used to teach and disseminate classifications in the endoscopy field. In this study, an NBI classification for gastric mucosal features seems to be easily learned for the identification of gastric preneoplastic

  10. INDOOR POSITIONING AND NAVIGATION BASED ON CONTROL SPHERECAL PANORAMIC IMAGES

    Directory of Open Access Journals (Sweden)

    T.-C. Huang

    2016-06-01

    Full Text Available Continuous indoor and outdoor positioning and navigation is the goal to achieve in the field of mobile mapping technology. However, accuracy of positioning and navigation will be largely degraded in indoor or occluded areas, due to receiving weak or less GNSS signals. Targeting the need of high accuracy indoor and outdoor positioning and navigation for mobile mapping applications, the objective of this study is to develop a novel method of indoor positioning and navigation with the use of spherical panoramic image (SPI. Two steps are planned in the technology roadmap. First, establishing a control SPI database that contains a good number of well-distributed control SPIs pre-acquired in the target space. A control SPI means an SPI with known exterior orientation parameters, which can be solved with a network bundle adjustment of SPIs. Having a control SPI database, the target space will be ready to provide the service of positioning and navigation. Secondly, the position and orientation of a newly taken SPI can be solved by using overlapped SPIs searched from the control SPI database. The method of matching SPIs and finding conjugate image features will be developed and tested. Two experiments will be planned and conducted in this paper to test the feasibility and validate the test results of the proposed methods. Analysis of appropriate number and distribution of needed control SPIs will also be included in the experiments with respect to different test cases.

  11. Periodontal and endodontic infectious/inflammatory profile in primary periodontal lesions with secondary endodontic involvement after a calcium hydroxide-based intracanal medication.

    Science.gov (United States)

    Duque, Thais M; Prado, Maira; Herrera, Daniel R; Gomes, Brenda P F A

    2018-03-23

    The aim of the present study was to investigate the effects of a calcium hydroxide-based intracanal medication (ICM) on periodontal and endodontic infectious/inflammatory contents and on periodontal clinical parameters in teeth with primary periodontal lesion and secondary endodontic involvement. Ten patients with abnormal pulp test results and deep probing depth derived from primary periodontal disease with secondary endodontic involvement were included. Samples were collected from root canals (RC) and periodontal pockets (PP) in order to investigate the microbiological status, levels of endotoxin (LPS), cytokines, and matrix metalloproteinases (MMP), before and after ICM. PCR was used for microbiological assessment. The kinetic-chromogenic LAL assay was used for LPS quantification. Quantikine ELISA kits were used for measurement of IL-1 α, IL-1 β, TNF-α, PGE 2 , MMP-2, MMP-3, MMP-8, MMP-9, and MMP-13 levels. The statistical analyses were made using the Friedman and Wilcoxon tests (p  0.05); however, the levels of the other MMPs and cytokines were reduced (p < 0.05). After 1 year of the root canal treatment, tooth mobility was significantly reduced (p ≤ 0.05). The use of a calcium hydroxide-based ICM showed positive effects for periodontal treatment prognosis, as it reduced LPS, cytokine, and MMP levels in periodontal pockets. Patients presenting deep probing depth and undergoing periodontal treatment for at least 6 months, with no positive response to periodontal therapy, might benefit with the endodontic treatment.

  12. Oncogenic human papilloma virus and cervical pre-cancerous lesions in brothel-based sex workers in India

    Directory of Open Access Journals (Sweden)

    Kamalesh Sarkar

    Full Text Available Summary: A community-based cross-sectional study was conducted in brothel-based sex workers of West Bengal, Eastern India, to determine their oncogenic human papillomavirus (HPV status and the presence of pre-cancerous lesions. A total of 229 sex workers from three districts of West Bengal participated in the study. All the study participants were interviewed with the aid of a pre-tested questionnaire to determine their sociodemographics, risk behaviour and risk perceptions after obtaining informed verbal consent. The interview was followed by collection of cervical cells from all participants using a disposable vaginal speculum and cervical cytobrush. Oncogenic HPV DNA was detected by real-time polymerase chain reaction (PCR. A simultaneous Papanicolaou test (‘Pap smear’ was performed to detect cervical cytological abnormalities. Overall, the prevalence of oncogenic HPV was found to be 25% (58/229 among the studied population. A subset (n = 112 of the sample was tested separately to determine the existence and magnitude of HPV genotypes 16 and 18. The results showed that genotype 16 was prevalent in 10% (11/112, genotype 18 in 7% (8/112 and both genotype 16 and 18 in 7% (8/112. The HPV prevalence rate showed a decreasing trend with age, being 71.4% in the 10–19 years age group, 32.3% in the 20–29 years age group, 18.3% in the 30–39 years age group and 2.5% in the ≥40 years age group (statistically significant differences, P ≤ 0.00001. Considering the duration of sex work, oncogenic HPV prevalence was found to be 55% (n = 21 and 19% (n = 35 in sex workers with a sex working duration of ≤1 year and >1 year, respectively. This difference was found to be statistically significant both by univariate and multivariate analysis. In this study, it was observed that sex workers with an average number of daily clients of six or more had an HPV prevalence of 67% (n = 6, those with four to five clients had a prevalence of 45% (n

  13. Thyroid malignancy among goitrous thyroid lesions: a review of hospital-based studies in Malaysia and Myanmar.

    Science.gov (United States)

    Htwe, T T

    2012-03-01

    Endemic goitre is a major concern in many parts of the world, including Southeast Asia. Goitrous thyroid lesion is postulated as a precursor lesion to thyroid cancer (TC). This paper reviews the prevalence rates and characteristics of TC among cases of goitrous thyroid-swelling in different parts of Malaysia and Myanmar. Recorded data from hospital-based retrospective studies of thyroid cases, whose study periods ranged from three to 11 years, were analysed. These included research findings from the author's publications as well as other published review articles of retrospective analyses. The incidence of TC varies among gender, age, race/ethnicity and histological type. There appears to be a higher rate of occurrence among females aged 21-60 years. Papillary thyroid carcinoma is the more common histological type compared to follicular cancer. This review also presents a descriptive analysis and discussion on studies conducted in other countries. Further exploration is warranted in order to uncover the possible risk factors for the rising incidence of TC.

  14. Intraosseous osteolytic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Adler, C.P.; Wenz, W.

    1981-10-01

    Any pathological damage occurring in a bone will produce either an osteolytic or osteosclerotic lesion which can be seen in the macroscopic specimen as well as in the roentgenogram. Various bone lesions may lead to local destructions of the bone. An osteoma or osteoplastic osteosarcoma produces an osteosclerotic lesion showing a dense mass in the roentgenogram; a chondroblastoma or an osteoclastoma, on the other hand, induces an osteolytic focal lesion. This paper presents examples of different osteolytic lesions of the humerus. An osteolytic lesion seen in the roentgenogram may be either produced by an underlying non-ossifying fibroma of the bone, by fibrous dysplasia, osteomyelitis or Ewing's sarcoma. Differential diagnostic considerations based on the radiological picture include eosinophilic bone granuloma, juvenile or aneurysmal bone cyst, multiple myeloma or bone metastases. Serious differential diagnostic problems may be involved in case of osteolytic lesions occurring in the humerus. Cases of this type involving complications have been reported and include the presence of an teleangiectatic osteosarcoma as well as that of a hemangiosarcoma of the bone.

  15. Consensus-based identification of factors related to false-positives in ultrasound scanning of synovitis and tenosynovitis.

    Science.gov (United States)

    Ikeda, Kei; Narita, Akihiro; Ogasawara, Michihiro; Ohno, Shigeru; Kawahito, Yutaka; Kawakami, Atsushi; Ito, Hiromu; Matsushita, Isao; Suzuki, Takeshi; Misaki, Kenta; Ogura, Takehisa; Kamishima, Tamotsu; Seto, Yohei; Nakahara, Ryuichi; Kaneko, Atsushi; Nakamura, Takayuki; Henmi, Mihoko; Fukae, Jun; Nishida, Keiichiro; Sumida, Takayuki; Koike, Takao

    2016-01-01

    We aimed to identify causes of false-positives in ultrasound scanning of synovial/tenosynovial/bursal inflammation and provide corresponding imaging examples. We first performed systematic literature review to identify previously reported causes of false-positives. We next determined causes of false-positives and corresponding example images for educational material through Delphi exercises and discussion by 15 experts who were an instructor and/or a lecturer in the 2013 advanced course for musculoskeletal ultrasound organized by Japan College of Rheumatology Committee for the Standardization of Musculoskeletal Ultrasonography. Systematic literature review identified 11 articles relevant to sonographic false-positives of synovial/tenosynovial inflammation. Based on these studies, 21 candidate causes of false-positives were identified in the consensus meeting. Of these items, 11 achieved a predefined consensus (≥ 80%) in Delphi exercise and were classified as follows: (I) Gray-scale assessment [(A) non-specific synovial findings and (B) normal anatomical structures which can mimic synovial lesions due to either their low echogenicity or anisotropy]; (II) Doppler assessment [(A) Intra-articular normal vessels and (B) reverberation)]. Twenty-four corresponding examples with 49 still and 23 video images also achieved consensus. Our study provides a set of representative images that can help sonographers to understand false-positives in ultrasound scanning of synovitis and tenosynovitis.

  16. Strength-based leadership coaching in organizations an evidence-based guide to positive leadership development

    CERN Document Server

    MacKie, Doug

    2016-01-01

    Positive organizational psychology, with its focus on the identification and development of strengths, is a natural ally to executive development and leadership coaching. However, this approach is only just beginning to come to the attention of organizations and consequently, the research base for strength-based coaching is in its early stages of development. Strength-based Leadership Coaching in Organizations reviews strength-based approaches to positive leadership development and evaluates the evidence for their effectiveness, critically assesses their apparent distinctiveness and considers how strengths can be reliably assessed and developed in their organizational context. This book reviews key areas of leader and team development are reviewed and outlines and describes a model of strengths development in organizations. The application of strength-based leadership coaching will be discussed from the managerial and external perspective within the context of career stage, seniority, role challenges and orga...

  17. Cylinder Position Servo Control Based on Fuzzy PID

    Directory of Open Access Journals (Sweden)

    Shibo Cai

    2013-01-01

    Full Text Available The arbitrary position control of cylinder has always been the hard challenge in pneumatic system. We try to develop a cylinder position servo control method by combining fuzzy PID with the theoretical model of the proportional valve-controlled cylinder system. The pressure differential equation of cylinder, pressure-flow equation of proportional valve, and moment equilibrium equation of cylinder are established. And the mathematical models of the cylinder driving system are linearized. Then fuzzy PID control algorithm is designed for the cylinder position control, including the detail analysis of fuzzy variables and domain, fuzzy logic rules, and defuzzification. The stability of the proposed fuzzy PID controller is theoretically proved according to the small gain theorem. Experiments for targets position of 250 mm, 300 mm, and 350 mm were done and the results showed that the absolute error of the position control is less than 0.25 mm. And comparative experiment between fuzzy PID and classical PID verified the advantage of the proposed algorithm.

  18. Lesion progression in post-treatment persistent endodontic lesions.

    Science.gov (United States)

    Yu, Victoria Soo Hoon; Messer, Harold Henry; Shen, Liang; Yee, Robert; Hsu, Chin-ying Stephen

    2012-10-01

    Radiographic lesions related to root-filled teeth may persist for long periods after treatment and are considered to indicate failure of initial treatment. Persistent lesions are found in a proportion of cases, but information on lesion progression is lacking. This study examined the incidence of lesion improvement, remaining unchanged, and deterioration among persistent lesions in a group of patients recruited from a university-based clinic and identified potential predictors for lesion progression. Patients of a university clinic with persistent endodontic lesions at least 4 years since treatment and with original treatment radiographs available were recruited with informed consent. Data were obtained by interview and from dental records and clinical and radiographic examinations. Univariate and multivariate statistical analyses were carried out by using SPSS (version 19). One hundred fifty-one persistent lesions were identified in 114 patients. A majority of the lesions (107, 70.9%) received treatment between 4 and 5 years prior. Eighty-six lesions (57.0%) improved, 18 (11.9%) remained unchanged, and 47 (31.1%) deteriorated since treatment. Potential predictors for lesions that did not improve included recall lesion size, pain on biting at recall examination, history of a postobturation flare-up, and a non-ideal root-filling length (P < .05). Lesions that had persisted for a longer period appeared less likely to be improving (relative risk, 1.038; 95% confidence interval, 1.000-1.077). A specific time interval alone should not be used to conclude that a lesion will not resolve without intervention. This study identified several clinical factors that are associated with deteriorating persistent lesions, which should aid in identifying lesions that require further intervention. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  19. Position Detection Based on Intensities of Reflected Infrared Light

    DEFF Research Database (Denmark)

    Christensen, Henrik Vie

    measurements of reflected light intensities, and includes easy calibration. The method for reconstructing 3D positions has been implemented in a prototype of a “non-Touch Screen” for a computer, so that the user can control a cursor in three dimensions by moving his/hers hand in front of the computer screen....... The 2D position reconstruction method is mplemented in a prototype of a human-machine interface (HMI) for an electrically powered wheelchair, such that the wheelchair user can control the movement of the wheelchair by head movements. Both “non-Touch Screen” prototype and wheelchair HMI has been tested...

  20. Position Mooring Control Based on a Structural Reliability Criterion

    DEFF Research Database (Denmark)

    Fang, Shaoji; Leira, Bernt J.; Blanke, Mogens

    2013-01-01

    is achieved using structural reliability indices in a cost function, where both the mean mooring-line tension and dynamic effects are considered. An optimal set-point is automatically produced without need for manual interaction. The parameters of the extreme value distribution are calculated on-line thereby...... mooring lines simultaneously from exceeding a stress threshold, this paper suggests a new algorithm to determine the reference position and an associated control system. The safety of each line is assessed through a structural reliability index. A reference position where all mooring lines are safe...

  1. Can the Diagnostics of Triangular Fibrocartilage Complex Lesions Be Improved by MRI-Based Soft-Tissue Reconstruction? An Imaging-Based Workup and Case Presentation.

    Science.gov (United States)

    Hammer, Niels; Hirschfeld, Ulrich; Strunz, Hendrik; Werner, Michael; Wolfskämpf, Thomas; Löffler, Sabine

    2017-01-01

    Introduction . The triangular fibrocartilage complex (TFCC) provides both mobility and stability of the radiocarpal joint. TFCC lesions are difficult to diagnose due to the complex anatomy. The standard treatment for TFCC lesions is arthroscopy, posing surgery-related risks onto the patients. This feasibility study aimed at developing a workup for soft-tissue reconstruction using clinical imaging, to verify these results in retrospective patient data. Methods . Microcomputed tomography ( μ -CT), 3 T magnetic resonance imaging (MRI), and plastination were used to visualize the TFCC in cadaveric specimens applying segmentation-based 3D reconstruction. This approach further trialed the MRI dataset of a patient with minor radiological TFCC alterations but persistent pain. Results . TFCC reconstruction was impossible using μ -CT only but feasible using MRI, resulting in an appreciation of its substructures, as seen in the plastinates. Applying this approach allowed for visualizing a Palmer 2C lesion in a patient, confirming ex postum the arthroscopy findings, being markedly different from MRI (Palmer 1B). Discussion . This preliminary study showed that image-based TFCC reconstruction may help to identify pathologies invisible in standard MRI. The combined approach of μ -CT, MRI, and plastination allowed for a three-dimensional appreciation of the TFCC. Image quality and time expenditure limit the approach's usefulness as a diagnostic tool.

  2. Can the Diagnostics of Triangular Fibrocartilage Complex Lesions Be Improved by MRI-Based Soft-Tissue Reconstruction? An Imaging-Based Workup and Case Presentation

    Directory of Open Access Journals (Sweden)

    Niels Hammer

    2017-01-01

    Full Text Available Introduction. The triangular fibrocartilage complex (TFCC provides both mobility and stability of the radiocarpal joint. TFCC lesions are difficult to diagnose due to the complex anatomy. The standard treatment for TFCC lesions is arthroscopy, posing surgery-related risks onto the patients. This feasibility study aimed at developing a workup for soft-tissue reconstruction using clinical imaging, to verify these results in retrospective patient data. Methods. Microcomputed tomography (μ-CT, 3 T magnetic resonance imaging (MRI, and plastination were used to visualize the TFCC in cadaveric specimens applying segmentation-based 3D reconstruction. This approach further trialed the MRI dataset of a patient with minor radiological TFCC alterations but persistent pain. Results. TFCC reconstruction was impossible using μ-CT only but feasible using MRI, resulting in an appreciation of its substructures, as seen in the plastinates. Applying this approach allowed for visualizing a Palmer 2C lesion in a patient, confirming ex postum the arthroscopy findings, being markedly different from MRI (Palmer 1B. Discussion. This preliminary study showed that image-based TFCC reconstruction may help to identify pathologies invisible in standard MRI. The combined approach of μ-CT, MRI, and plastination allowed for a three-dimensional appreciation of the TFCC. Image quality and time expenditure limit the approach’s usefulness as a diagnostic tool.

  3. A fully automatic end-to-end method for content-based image retrieval of CT scans with similar liver lesion annotations.

    Science.gov (United States)

    Spanier, A B; Caplan, N; Sosna, J; Acar, B; Joskowicz, L

    2018-01-01

    The goal of medical content-based image retrieval (M-CBIR) is to assist radiologists in the decision-making process by retrieving medical cases similar to a given image. One of the key interests of radiologists is lesions and their annotations, since the patient treatment depends on the lesion diagnosis. Therefore, a key feature of M-CBIR systems is the retrieval of scans with the most similar lesion annotations. To be of value, M-CBIR systems should be fully automatic to handle large case databases. We present a fully automatic end-to-end method for the retrieval of CT scans with similar liver lesion annotations. The input is a database of abdominal CT scans labeled with liver lesions, a query CT scan, and optionally one radiologist-specified lesion annotation of interest. The output is an ordered list of the database CT scans with the most similar liver lesion annotations. The method starts by automatically segmenting the liver in the scan. It then extracts a histogram-based features vector from the segmented region, learns the features' relative importance, and ranks the database scans according to the relative importance measure. The main advantages of our method are that it fully automates the end-to-end querying process, that it uses simple and efficient techniques that are scalable to large datasets, and that it produces quality retrieval results using an unannotated CT scan. Our experimental results on 9 CT queries on a dataset of 41 volumetric CT scans from the 2014 Image CLEF Liver Annotation Task yield an average retrieval accuracy (Normalized Discounted Cumulative Gain index) of 0.77 and 0.84 without/with annotation, respectively. Fully automatic end-to-end retrieval of similar cases based on image information alone, rather that on disease diagnosis, may help radiologists to better diagnose liver lesions.

  4. APHRODITE: an Anomaly-based Architecture for False Positive Reduction

    NARCIS (Netherlands)

    Bolzoni, D.; Etalle, Sandro

    We present APHRODITE, an architecture designed to reduce false positives in network intrusion detection systems. APHRODITE works by detecting anomalies in the output traffic, and by correlating them with the alerts raised by the NIDS working on the input traffic. Benchmarks show a substantial

  5. Value added based on educational positions in Dutch secondary education

    NARCIS (Netherlands)

    Timmermans, Anneke C.; Bosker, Roel J.; de Wolf, Inge F.; Doolaard, Simone; van der Werf, Margaretha P.C.

    2014-01-01

    Estimating added value as an indicator of school effectiveness in the context of educational accountability often occurs using test or examination scores of students. This study investigates the possibilities of using scores for educational positions as an alternative indicator. A number of

  6. Coordination of two robot manipulators based on position measurements only

    NARCIS (Netherlands)

    Rodriguez Angeles, A.; Nijmeijer, H.

    2001-01-01

    In this note we propose a controller that solves the problem of coordination of two (or more) robots, under a master-slave scheme, in the case when only position measurements are available. The controller consists of a feedback control law, and two non-linear observers. It is shown that the

  7. Prediction of nucleosome positioning based on transcription factor binding sites.

    Directory of Open Access Journals (Sweden)

    Xianfu Yi

    Full Text Available BACKGROUND: The DNA of all eukaryotic organisms is packaged into nucleosomes, the basic repeating units of chromatin. The nucleosome consists of a histone octamer around which a DNA core is wrapped and the linker histone H1, which is associated with linker DNA. By altering the accessibility of DNA sequences, the nucleosome has profound effects on all DNA-dependent processes. Understanding the factors that influence nucleosome positioning is of great importance for the study of genomic control mechanisms. Transcription factors (TFs have been suggested to play a role in nucleosome positioning in vivo. PRINCIPAL FINDINGS: Here, the minimum redundancy maximum relevance (mRMR feature selection algorithm, the nearest neighbor algorithm (NNA, and the incremental feature selection (IFS method were used to identify the most important TFs that either favor or inhibit nucleosome positioning by analyzing the numbers of transcription factor binding sites (TFBSs in 53,021 nucleosomal DNA sequences and 50,299 linker DNA sequences. A total of nine important families of TFs were extracted from 35 families, and the overall prediction accuracy was 87.4% as evaluated by the jackknife cross-validation test. CONCLUSIONS: Our results are consistent with the notion that TFs are more likely to bind linker DNA sequences than the sequences in the nucleosomes. In addition, our results imply that there may be some TFs that are important for nucleosome positioning but that play an insignificant role in discriminating nucleosome-forming DNA sequences from nucleosome-inhibiting DNA sequences. The hypothesis that TFs play a role in nucleosome positioning is, thus, confirmed by the results of this study.

  8. Shape based automated detection of pulmonary nodules with surface feature based false positive reduction

    International Nuclear Information System (INIS)

    Nomura, Y.; Itoh, H.; Masutani, Y.; Ohtomo, K.; Maeda, E.; Yoshikawa, T.; Hayashi, N.

    2007-01-01

    We proposed a shape based automated detection of pulmonary nodules with surface feature based false positive (FP) reduction. In the proposed system, the FP existing in internal of vessel bifurcation is removed using extracted surface of vessels and nodules. From the validation with 16 chest CT scans, we find that the proposed CAD system achieves 18.7 FPs/scan at 90% sensitivity, and 7.8 FPs/scan at 80% sensitivity. (orig.)

  9. Lesion-based detection of early chemosensitivity using serial static FDG PET/CT in metastatic colorectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Buvat, Irene; Necib, Hatem [IMNC UMR 8165 CNRS - Paris 7 and Paris 11 Universities, Orsay cedex (France); Garcia, Camilo; Wagner, Antoine; Vanderlinden, Bruno; Flamen, Patrick [Universite Libre de Bruxelles, Nuclear Medicine Department, Institut Jules Bordet, Brussels (Belgium); Emonts, Patrick [Universite Libre de Bruxelles, Radiology Department, Institut Jules Bordet, Brussels (Belgium); Hendlisz, Alain [Universite Libre de Bruxelles, Digestive Oncology, Institut Jules Bordet, Brussels (Belgium)

    2012-10-15

    Medical oncology needs early identification of patients that are not responding to systemic therapy. {sup 18}F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) performed before and early during treatment has been proposed for this purpose. However, the best way to assess the change in FDG uptake between two scans has not been identified. We studied cutoff thresholds to identify responding tumours as a function of the method used to measure tumour uptake. The study included 28 metastatic colorectal cancer (mCRC) patients who underwent 2 FDG PET/CT scans (baseline and at day 14 of the first course of polychemotherapy). For 78 tumour lesions, 4 standardized uptake value (SUV) indices were measured: maximum SUV (SUV{sub max}) and mean SUV in a region obtained using an isocontour (SUV{sub 40} {sub %}), with each of these SUV normalized either by the patient body weight (BW) or body surface area (BSA). The per cent change and absolute change in tumour uptake between the baseline and the early PET scans were measured based on these four indices. These changes were correlated to the RECIST 1.0-based response using contrast-enhanced CT at baseline and at 6-8 weeks on treatment. The 78 tumours were classified as non-responding (NRL, n = 58) and responding lesions (RL, n = 20). Receiver-operating characteristic (ROC) curves characterizing the performance in NRL/RL classification using early FDG PET uptake had areas under the curve between 0.75 and 0.84, without significant difference between the indices. The cutoff threshold in FDG uptake per cent change to get a 95 % sensitivity of RL detection depended on the way uptake was measured: -14 % (specificity of 53 %) and -22 % (specificity of 64 %) for SUV{sub max} and SUV{sub 40} {sub %}, respectively. Thresholds expressed as absolute SUV decrease instead of per cent change were less sensitive to the SUV definition: an SUV decline by 1.2 yielded a sensitivity of RL detection of 95 % for SUV{sub max} and SUV{sub 40

  10. Secure positioning technique based on encrypted visible light map for smart indoor service

    Science.gov (United States)

    Lee, Yong Up; Jung, Gillyoung

    2018-03-01

    Indoor visible light (VL) positioning systems for smart indoor services are negatively affected by both cochannel interference from adjacent light sources and VL reception position irregularity in the three-dimensional (3-D) VL channel. A secure positioning methodology based on a two-dimensional (2-D) encrypted VL map is proposed, implemented in prototypes of the specific positioning system, and analyzed based on performance tests. The proposed positioning technique enhances the positioning performance by more than 21.7% compared to the conventional method in real VL positioning tests. Further, the pseudonoise code is found to be the optimal encryption key for secure VL positioning for this smart indoor service.

  11. Analysis of pulmonary coin lesions

    International Nuclear Information System (INIS)

    Kim, O; Kim, K. H.; Oh, K. K.; Park, C. Y.

    1979-01-01

    For A long time the solitary pulmonary nodule has remained a difficult problem to solve and has attracted a great deal of attension in recent years. Circumscribed coin lesions of the lung were generally peripheral in location with respect to the pulmonary hilus. Because of this, important clinical problem in management and diagnosis arise. Such a lesion is discovered through roentgenologic examination. So the roentgenologists is the first be in a position to offer advise. This presentation is an attempt to correlate a useful diagnosis with roentgenologic findings of pulmonary coin lesion which enables us to get differential diagnosis of benign and malignant lesion. Histologically proven 120 cases of the pulmonary coin lesion during the period of 8 years were reviewed through plain film, tomogram, bronchoscopy, variable laboratory findings, and clinical history. The results are as follows: 1. Male to female sex ratio was 3 : 1. In age distribution, most of the malignant pulmonary coin lesion appeared in 6th decade (39%) and 5th decade (27%). In benign lesion, the most cases were in 3 rd decade. 2. Pathological cell type are as follows: Primary bronchogenic cancer 43.3%, tuberculoma 25.8%, inflammatory lesion 17.5%, benign tumor 10%, and bronchial adenoma, harmartoma, A.V. malformation, mesothelioma, are 1 case respectively. As a result benign and malignant lesion showed equal distribution (49.1% : 50.3%). 3. In symptom analysis ; cough is the most common (43.5%) symptom in malignant lesion, next follows hemoptysis (20.9%) and chest pain (14.5%). In benign lesion, most of the patient (32.7%) did not complain any symptom. 4. In malignant lesion, the most common nodular size was 4 cm (32.3%), and in benign lesion 2 cm sized coin was most common (39.3%). 5. In general, margin of nodule was very sharp and well demarcated in benign lesion (83.3%), and in malignant lesion that was less demarcated and poorly defined. 6. Most case of calcification (82.7%) was seen in benign

  12. Epidemiology of benign paroxysmal positional vertigo: a population based study

    Science.gov (United States)

    von Brevern, M; Radtke, A; Lezius, F; Feldmann, M; Ziese, T; Lempert, T; Neuhauser, H

    2007-01-01

    Objectives To examine the prevalence and incidence, clinical presentation, societal impact and comorbid conditions of benign paroxysmal positional vertigo (BPPV) in the general population. Methods Cross‐sectional, nationally representative neurotological survey of the general adult population in Germany with a two stage sampling design: screening of 4869 participants from the German National Telephone Health Interview Survey 2003 (response rate 52%) for moderate or severe dizziness or vertigo, followed by validated neurotological interviews (n = 1003; response rate 87%). Diagnostic criteria for BPPV were at least five attacks of vestibular vertigo lasting <1 min without concomitant neurological symptoms and invariably provoked by typical changes in head position. In a concurrent validation study (n = 61) conducted in two specialised dizziness clinics, BPPV was detected by our telephone interview with a specificity of 92% and a sensitivity of 88% (positive predictive value 88%, negative predictive value 92%). Results BPPV accounted for 8% of individuals with moderate or severe dizziness/vertigo. The lifetime prevalence of BPPV was 2.4%, the 1 year prevalence was 1.6% and the 1 year incidence was 0.6%. The median duration of an episode was 2 weeks. In 86% of affected individuals, BPPV led to medical consultation, interruption of daily activities or sick leave. In total, only 8% of affected participants received effective treatment. On multivariate analysis, age, migraine, hypertension, hyperlipidaemia and stroke were independently associated with BPPV. Conclusion BPPV is a common vestibular disorder leading to significant morbidity, psychosocial impact and medical costs. PMID:17135456

  13. A morphological study of penile chancroid lesions in human immunodeficiency virus (HIV)-positive and -negative African men with a hypothesis concerning the role of chancroid in HIV transmission.

    Science.gov (United States)

    Magro, C M; Crowson, A N; Alfa, M; Nath, A; Ronald, A; Ndinya-Achola, J O; Nasio, J

    1996-10-01

    Chancroid, the most common cause of genital ulceration in Africa, is known to be associated epidemiologically with heterosexual transmission of human immunodeficiency virus (HIV). The pathophysiological mechanisms by which chancroid might facilitate the spread of HIV are obscure. To investigate the role of chancroid in HIV transmission, the authors studied the histological features of biopsies from 11 men with penile chancroid lesions including five who were serologically positive for HIV. The histomorphologic and immunophenotypic nature of the inflammatory infiltrates suggests that there is a significant role for cell-mediated immunity in the host response to Hemophilus ducreyi infection. This response may be critical to the role of chancroid in HIV transmission.

  14. Deep learning based classification of morphological patterns in RCM to guide noninvasive diagnosis of melanocytic lesions (Conference Presentation)

    Science.gov (United States)

    Kose, Kivanc; Bozkurt, Alican; Ariafar, Setareh; Alessi-Fox, Christi A.; Gill, Melissa; Dy, Jennifer G.; Brooks, Dana H.; Rajadhyaksha, Milind

    2017-02-01

    In this study we present a deep learning based classification algorithm for discriminating morphological patterns that appear in RCM mosaics of melanocytic lesions collected at the dermal epidermal junction (DEJ). These patterns are classified into 6 distinct types in the literature: background, meshwork, ring, clod, mixed, and aspecific. Clinicians typically identify these morphological patterns by examination of their textural appearance at 10X magnification. To mimic this process we divided mosaics into smaller regions, which we call tiles, and classify each tile in a deep learning framework. We used previously acquired DEJ mosaics of lesions deemed clinically suspicious, from 20 different patients, which were then labelled according to those 6 types by 2 expert users. We tried three different approaches for classification, all starting with a publicly available convolutional neural network (CNN) trained on natural image, consisting of a series of convolutional layers followed by a series of fully connected layers: (1) We fine-tuned this network using training data from the dataset. (2) Instead, we added an additional fully connected layer before the output layer network and then re-trained only last two layers, (3) We used only the CNN convolutional layers as a feature extractor, encoded the features using a bag of words model, and trained a support vector machine (SVM) classifier. Sensitivity and specificity were generally comparable across the three methods, and in the same ranges as our previous work using SURF features with SVM . Approach (3) was less computationally intensive to train but more sensitive to unbalanced representation of the 6 classes in the training data. However we expect CNN performance to improve as we add more training data because both the features and the classifier are learned jointly from the data. *First two authors share first authorship.

  15. [The spa-and-health resort-based rehabilitation of the patients presenting with frequently recurring erosive and ulcerative lesions in the oesophagus, stomach, and duodenum in the phase of subsiding exacerbation].

    Science.gov (United States)

    Efimenko, N V; Kaĭsinova, A S

    2014-01-01

    To develop a new medical technology for the spa-and-health resort-based treatment of the patients presenting with frequently recurring erosive and ulcerative lesions in the oesophagus, stomach, and duodenum in the phase of subsiding exacerbation. A total of 100 patients presenting with frequently recurring erosive and ulcerative lesions in the oesophagus, stomach, and duodenum in the phase of subsiding exacerbation were available for the examination that included detailed investigations of the clinical picture, characteristics of the immune status, and psychological testing before and after a course of the spa-and-health resort-based treatment. The effectiveness of two therapeutic modalities was evaluated. One of them (control) prescribed to 50 patients consisted of standard antiulcer pharmacotherapy in combination with Essentuki Novaya drinking mineral water and carbon dioxide mineral baths, the other given to 50 patients included radon baths instead of carbon dioxide mineral baths. The combined application of drinking mineral waters, radon baths, and standard antiulcer pharmacotherapy produced the most conspicuous clinical effect in the framework of spa-and-health resort-based rehabilitation of the patients presenting with frequently recurring erosive and ulcerative lesions in the oesophagus, stomach, and duodenum in the phase of subsiding exacerbation as confirmed by positive dynamics of their psychoemotional status in 97.7% of the cases, regression of pain syndrome (91.5%), and improvement of humoral and cellular immunity (94%). An important result of the spa-and-health resort-based rehabilitation is the intensification of the reparative processes in gastroduodenal mucosa responsible for the healing of ulcers and erosions in 94.7% of the patients. The spa-and-health resort-based rehabilitation is a pathogenetically sound and efficacious approach to the management of the patients presenting with frequently recurring erosive and ulcerative lesions in the

  16. CYSTIC LESIONS OF THE BRAIN - A CLASSIFICATION BASED ON PATHOGENESIS, WITH CONSIDERATION OF HISTOLOGICAL AND RADIOLOGICAL FEATURES

    NARCIS (Netherlands)

    GO, KG; HEW, JM; KAMMAN, RL; MOLENAAR, WM; PRUIM, J; BLAAUW, EH

    A classification of the existing multitude of cystic lesions of the brain is proposed, which allows an understanding of their genesis and consequent therapeutic implications, as well as their diagnostic characteristics. Essentially, cerebral cystic lesions may be classified into the following

  17. A review on prevention and treatment of post-orthodontic white spot lesions - evidence-based methods and emerging technologies

    DEFF Research Database (Denmark)

    Bergstrand, Fredrik; Twetman, Svante

    2011-01-01

    The aim of this paper was to update the evidence for primary and secondary prevention (treatment) of white spot lesions (WSL) adjacent to fixed orthodontic appliances.......The aim of this paper was to update the evidence for primary and secondary prevention (treatment) of white spot lesions (WSL) adjacent to fixed orthodontic appliances....

  18. Assessment of Feasibility to Use Computer Aided Texture Analysis Based Tool for Parametric Images of Suspicious Lesions in DCE-MR Mammography

    Directory of Open Access Journals (Sweden)

    Mehmet Cemil Kale

    2013-01-01

    Full Text Available Our aim was to analyze the feasibility of computer aided malignant tumor detection using the traditional texture analysis applied on two-compartment-based parameter pseudoimages of dynamic contrast-enhanced magnetic resonance (DCE-MR breast image data. A major contribution of this research will be the through-plane assessment capability. Texture analysis was performed on two-compartment-based pseudo images of DCE-MRI datasets of breast data of eight subjects. The resulting texture parameter pseudo images were inputted to a feedforward neural network classification system which uses the manual segmentations of a primary radiologist as a gold standard, and each voxel was assigned as malignant or nonmalignant. The classification results were compared with the lesions manually segmented by a second radiologist. Results show that the mean true positive fraction (TPF and false positive fraction (FPF performance of the classifier vs. primary radiologist is statistically as good as the mean TPF and FPF performance of the second radiologist vs. primary radiologist with a confidence interval of 95% using a one-sample -test with . In the experiment implemented on all of the eight subjects, all malignant tumors marked by the primary radiologist were classified to be malignant by the computer classifier. Our results have shown that neural network classification using the textural parameters for automated screening of two-compartment-based parameter pseudo images of DCE-MRI as input data can be a supportive tool for the radiologists in the preassessment stage to show the possible cancerous regions and in the postassessment stage to review the segmentations especially in analyzing complex DCE-MRI cases.

  19. A model to environmental monitoring based on glutathione-S-transferase activity and branchial lesions in catfish

    Science.gov (United States)

    Neta, Raimunda Nonata Fortes Carvalho; Torres, Audalio Rebelo

    2017-11-01

    In this work, we validate the glutathione-S-transferase and branchial lesions as biomarkers in catfish Sciades herzbergii to obtain a predictive model of the environmental impact effects in a harbor of Brazil. The catfish were sampled from a port known to be contaminated with heavy metals and organic compounds and from a natural reserve in São Marcos Bay, Maranhão. Two biomarkers, hepatic glutathione S-transferase (GST) activity and branchial lesions were analyzed. The values for GST activity were modeled with the occurrence of branchial lesions by fitting a third order polynomial. Results from the mathematical model indicate that GST activity has a strong polynomial relationship with the occurrence of branchial lesions in both the wet and the dry seasons, but only at the polluted port site. Our mathematic model indicates that when the GST ceases to act, serious branchial lesions are observed in the catfish of the contaminated port area.

  20. Positive versus Negative Communication Strategies in Task-Based Learning

    Science.gov (United States)

    Rohani, Siti

    2013-01-01

    This study aimed at describing how the implementation of Task-Based Learning (TBL) would shape or change students' use of oral communication strategies. Students' problems and strategies to solve the problems during the implementation of TBL were also explored. The study was a mixed method, employing both quantitative and qualitative analysis…

  1. A Hybrid Positioning Method Based on Hypothesis Testing

    DEFF Research Database (Denmark)

    Amiot, Nicolas; Pedersen, Troels; Laaraiedh, Mohamed

    2012-01-01

    maxima. We propose to first estimate the support region of the two peaks of the likelihood function using a set membership method, and then decide between the two regions using a rule based on the less reliable observations. Monte Carlo simulations show that the performance of the proposed method...

  2. Position Paper: Moving Task-Based Language Teaching Forward

    Science.gov (United States)

    Ellis, Rod

    2017-01-01

    The advocacy of task-based language teaching (TBLT) has met with resistance. The critiques of TBLT and the misconceptions that underlie them have already been addressed in Ellis (2009) and Long (2016). The purpose of this article is to move forward by examining a number of real problems that TBLT faces--such as how a "task" should be…

  3. Successful combination immunotherapy of anti-gamma aminobutyric acid (GABA)A receptor antibody-positive encephalitis with extensive multifocal brain lesions.

    Science.gov (United States)

    Fukami, Yuki; Okada, Hiroaki; Yoshida, Mari; Yamaguchi, Keiji

    2017-08-31

    A 78-year old woman who presented with akinetic mutism was admitted to our hospital. Brain MRI showed multifocal increased T 2 /FLAIR signal with extensive cortical-subcortical involvement. We suspected autoimmune encephalitis and the patient received methylprednisolone pulse. Her conscious level gradually recovered, but later relapsed again and presented with refractory status epilepticus. We treated her with intravenous immunoglobulin, plasma exchange and pulsed cyclophosphamide, with satisfactory response. A brain biopsy showed perivascular lymphocytic infiltrates and reactive gliosis. Anti-gamma aminobutyric acid (GABA) A receptor antibodies test came back to be positive after her recovery, and the diagnosis of anti-GABA A receptor antibody-positive encephalitis was made. This is a very rare case where brain biopsies were performed in a patient with anti-GABA A receptor antibody-positive encephalitis.

  4. Changing pattern of oral cavity lesions and personal habits over a decade: Hospital based record analysis from Allahabad

    Directory of Open Access Journals (Sweden)

    Misra Vatsala

    2009-01-01

    Full Text Available Aim: To do a prospective clinicohistological study of premalignant and malignant lesions of the oral cavity, and compare it with a 10-year retrospective data, especially in terms of incidence, age distribution, personal habits, and site and type of lesion. Material and Methods: Sections from 776 lesions of the oral cavity, which included 647 lesions of a 10-year (1993 - 2003 retrospective study and 129 lesions of a one-year (2003 - 2004 prospective study, were observed clinically, and a histological correlation was carried out. Results: Premalignant lesions included 78 cases of leukoplakia, 68 cases of oral submucous fibrosis, and 76 cases of squamous papilloma. Their incidence has increased in the last decade from 0.15 to 0.53. These lesions commonly presented in the fourth decade of life, as white patches in leukoplakia and oral submucous fibrosis, and as a growth in squamous cell papilloma. Squamous cell carcinoma was the commonest lesion (57%. Its incidence has increased significantly in the last decade. The mean age of presentation was the sixth decade. A personal history of tobacco chewing was given by most of the patients in the retrospective group, while the use of pan masala was found to be maximum in the prospective group. The overall agreement between the clinical and histological diagnosis was 95.36% (740 / 776 and the kappa coefficient of agreement was 0.9256. Conclusion: Histology along with a detailed clinical workup was found to be a useful, reliable, and accurate diagnostic technique for lesions of the oral cavity. An increase in premalignant lesions in the prospective study, associated with increased pan masala intake is alarming and needs to be taken care of.

  5. Epidemiology of benign paroxysmal positional vertigo: a population based study.

    Science.gov (United States)

    von Brevern, M; Radtke, A; Lezius, F; Feldmann, M; Ziese, T; Lempert, T; Neuhauser, H

    2007-07-01

    To examine the prevalence and incidence, clinical presentation, societal impact and comorbid conditions of benign paroxysmal positional vertigo (BPPV) in the general population. Cross-sectional, nationally representative neurotological survey of the general adult population in Germany with a two stage sampling design: screening of 4869 participants from the German National Telephone Health Interview Survey 2003 (response rate 52%) for moderate or severe dizziness or vertigo, followed by validated neurotological interviews (n = 1003; response rate 87%). Diagnostic criteria for BPPV were at least five attacks of vestibular vertigo lasting vertigo. The lifetime prevalence of BPPV was 2.4%, the 1 year prevalence was 1.6% and the 1 year incidence was 0.6%. The median duration of an episode was 2 weeks. In 86% of affected individuals, BPPV led to medical consultation, interruption of daily activities or sick leave. In total, only 8% of affected participants received effective treatment. On multivariate analysis, age, migraine, hypertension, hyperlipidaemia and stroke were independently associated with BPPV. BPPV is a common vestibular disorder leading to significant morbidity, psychosocial impact and medical costs.

  6. Abuse of dominant position in Albania based in jurisprudence

    Directory of Open Access Journals (Sweden)

    Endri Papajorgji

    2016-11-01

    Full Text Available Competition law and cartel is the basis of a modern economy. While in the US, competition law exists and is terminologically known and is part of legislation since 1890 (Sherman Law, in Europe, it has become part of the founding treaties of the EU since 1957 by the Treaty of Rome. However, at that time, “culture of competition” would be born in the member states of the EU, which traditionally favour cartel agreements, state aid and the promotion of national products. Some EU member states have included competition law in their national legislation in the early 90-s. Rules were set for the first time on competition in the coal and steel market under Articles 65 and 66 of the Treaty of Rome, constituted a new terminology for member states. Albania has worked during these 24 years of democracy, to apply the basic principles of market economy and along with it the Lisbon Treaty, Regulations and EU Directives in the frame of competition. Main purpose of this manuscript is to give an overview of the abuse of dominant position in the frame of the most important court decision of this legal institution in Albania.

  7. Study protocol for an approach based on diagnosis and therapy of cutaneous radiation induced lesions

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Vallerga, Maria B.; Radl, Analia; Portas, Mercedes

    2008-01-01

    -rector cancer patients (24.9 ± 10.4 minutes). In this paper, 10 representative cases, in which the research protocol was applied, have been evaluated retrospectively. Therapeutic response and its correlation with radiosensitivity test results have also been studied. Overall, 4 cases showed positive (favorable) local recovery and almost complete to complete remission of signs and symptoms after 5 to 12 months of the beginning of the treatment. In these patients, both MN frequencies and comet assay showed values compatible with normal (average) radiosensitivity. However, three cases showing average radio sensitivity presented complications attributed to radiation exposure (treatment or diagnosis) or to co-morbidity factors. Finally, 3 cases presented a partial response with pain and acute repetitive crisis. In vitro radiosensitivity test results indicated that these patients (over-reactors) presented a greater risk than average patients of developing radiation toxicity. These results would ensure in vitro radiosensitivity test to constitute one of the prognostic score parameters, jointly with applied radiation dose, radiation quality, localization (including thickness and vascularisation of the dermis) in case of CRS for the design of therapeutic strategies. The appearance in delay of this syndrome often results in non specialized medical treatment, so the conformation of an ad hoc interdisciplinary group for CRS approach offer to these patients a content frame that provides them with the availability of diagnostic methods and therapeutic strategies, tailoring patient's treatment both in normal and in radiological emergency conditions. (author)

  8. Study Protocol for an Approach Based on Diagnosis and Therapy of Cutaneous Radiation Induced Lesions

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Vallerga, M.B.; Radl, A.; Portas, M.

    2011-01-01

    -rector cancer patients (24.9 ± 10.4 minutes). In this paper, 10 representative cases, in which the research protocol was applied, have been evaluated retrospectively. Therapeutic response and its correlation with radiosensitivity test results have also been studied. Overall, 4 cases showed positive (favorable) local recovery and almost complete to complete remission of signs and symptoms after 5 to 12 months of the beginning of the treatment. In these patients, both MN frequencies and comet assay showed values compatible with normal (average) radiosensitivity. However, three cases showing average radiosensitivity presented complications attributed to radiation exposure (treatment or diagnosis) or to comorbidity factors. Finally, 3 cases presented a partial response with pain and acute repetitive crisis. In vitro radiosensitivity test results indicated that these patients (over-reactors) presented a greater risk than average patients of developing radiation toxicity. These results would ensure in vitro radiosensitivity test to constitute one of the prognostic score parameters, jointly with applied radiation dose, radiation quality, localization (including thickness and vascularization of the dermis) in case of CRS for the design of therapeutic strategies. The appearance in delay of this syndrome often results in non specialized medical treatment, so the conformation of an ad hoc interdisciplinary group for CRS approach offer to these patients a content frame that provides them with the availability of diagnostic methods and therapeutic strategies, tailoring patient's treatment both in normal and in radiological emergency conditions. (authors)

  9. Indoor Positioning Using Nonparametric Belief Propagation Based on Spanning Trees

    Directory of Open Access Journals (Sweden)

    Savic Vladimir

    2010-01-01

    Full Text Available Nonparametric belief propagation (NBP is one of the best-known methods for cooperative localization in sensor networks. It is capable of providing information about location estimation with appropriate uncertainty and to accommodate non-Gaussian distance measurement errors. However, the accuracy of NBP is questionable in loopy networks. Therefore, in this paper, we propose a novel approach, NBP based on spanning trees (NBP-ST created by breadth first search (BFS method. In addition, we propose a reliable indoor model based on obtained measurements in our lab. According to our simulation results, NBP-ST performs better than NBP in terms of accuracy and communication cost in the networks with high connectivity (i.e., highly loopy networks. Furthermore, the computational and communication costs are nearly constant with respect to the transmission radius. However, the drawbacks of proposed method are a little bit higher computational cost and poor performance in low-connected networks.

  10. Design of personal positioning for coal mine based on mesh

    Energy Technology Data Exchange (ETDEWEB)

    Gao, W.H.; Ma, J.; Kang, L. [Taiyuan University of Science and Technology, Taiyuan (China). College of Electronic Information and Engineering

    2008-07-01

    This paper puts forward a method for a location system for colliery workers based on wireless mesh network combined with zigbee technology which supports IEEE 802.15.4 wireless communication standard, with low power dissipation. Data receipt and transmission by wireless communication is realized by RF chip MC13192 produced by the Freescale company. Data procession and analysis is achieved by an S3C2410A chip manufactured by Sumsung which belongs to the ARM9 16/32 RISC processor.

  11. Direct assay of radiation-induced DNA base lesions in mammalian cells

    International Nuclear Information System (INIS)

    1992-01-01

    Adenine (Ade), 2'-deoxyadenosine (dAdo), 5'-deoxyadenosine monophosphate (dAUT), single stranded poly adenylic acid [poly (dA)], double stranded deoxyadenylic-thymidylic acid [ds poly (dA-T)] and salmon testis DNA were irradiated with 500 Gy under oxic and anoxic conditions. The major damage products were analyzed by BPLC with optical detection and quantitated in terms of the percentage of the adenosine in each model compound found as a specific damage product. Outside of the Ade free base, 8-OH-dAdo was the major oxic damage product from each model compound. The type and quantity of the major damage products depended on the sequence and conformation of the model compounds under anoxic conditions. When dAdo and dAMP were irradiated under anoxic conditions, the major damage product was either the R or S isomer of 8,5'cdAdo and little Ade or α-dAdo was observed. However, when poly(dA), poly(dA-dT), and salmon testis DNA were γ-irradiated under nitrogen, the major deoxyadenosine damage product was identified as the α-anomer of deoxyadenosine. No α-deoxyadenosine was detected after irradiation under oxic conditions. The presence of nucleotides with the α-configuration at the anomeric carbon atom in the DNA chain may have a significant effect on its tertiary structure and possibly modify its biological activity

  12. One lesion, one virus: individual components of high-grade anal intraepithelial neoplasia in HIV-positive men contain a single HPV type

    NARCIS (Netherlands)

    Richel, Olivier; Quint, Koen D.; Lindeman, Jan; van Noesel, Carel J. M.; de Koning, Maurits N. C.; van den Munckhof, Henk A. M.; de Vries, Henry J. C.; Prins, Jan M.; Quint, Wim G. V.

    2014-01-01

    High-grade anal intraepithelial neoplasia (AIN) is present in many human immunodeficiency virus (HIV)-positive men who have sex with men. The major etiologic factor is infection with an oncogenic human papillomavirus (HPV) genotype. We investigated whether individual components of high-grade AIN are

  13. 76 FR 65540 - National Space-Based Positioning, Navigation, and Timing (PNT) Advisory Board; Meeting

    Science.gov (United States)

    2011-10-21

    .... L. 92-463, as amended), and the President's 2004 U.S. Space-Based Positioning, Navigation, and...-Based Positioning, Navigation and Timing Policy and Global Positioning System (GPS) modernization. Explore opportunities for enhancing the interoperability of GPS with other emerging international Global...

  14. Headache, migraine, and structural brain lesions and function: population based Epidemiology of Vascular Ageing-MRI study

    International Nuclear Information System (INIS)

    Kurth, T.; Mohamed, S.; Zhu, Y.C.; Dufouil, C.; Tzourio, Ch.; Kurth, T.; Zhu, Y.C.; Dufouil, C.; Tzourio, Ch.; Kurth, T.; Maillard, P.; Mazoyer, B.; Zhu, Y.C.; Chabriat, H.; Bousser, M.G.; Tzourio, Ch.; Zhu, Y.C.; Chabriat, H.; Bousser, M.G.; Mazoyer, B.

    2011-01-01

    Objective: To evaluate the association of overall and specific headaches with volume of white matter hyper-intensities, brain infarcts, and cognition. Design: Population based, cross sectional study. Setting: Epidemiology of Vascular Ageing study, Nantes, France. Participants: 780 participants (mean age 69, 58.5% women) with detailed headache assessment. Main outcome measures: Brain scans were evaluated for volume of white matter hyper-intensities (by fully automated imaging processing) and for classification of infarcts (by visual reading with a standardised assessment grid). Cognitive function was assessed by a battery of tests including the mini-mental state examination. Results: 163 (20.9%) participants reported a history of severe headache and 116 had migraine, of whom 17 (14.7%) reported aura symptoms. An association was found between any history of severe headache and increasing volume of white matter hyper-intensities. The adjusted odds ratio of being in the highest third for total volume of white matter hyper-intensities was 2.0 (95% confidence interval 1.3 to 3.1, P for trend 0.002) for participants with any history of severe headache when compared with participants without severe headache being in the lowest third. The association pattern was similar for all headache types. Migraine with aura was the only headache type strongly associated with volume of deep white matter hyper-intensities (highest third odds ratio 12.4, 1.6 to 99.4, P for trend 0.005) and with brain infarcts (3.4, 1.2 to 9.3). The location of infarcts was predominantly outside the cerebellum and brain stem. Evidence was lacking for cognitive impairment for any headache type with or without brain lesions. Conclusions: In this population based study, any history of severe headache was associated with an increased volume of white matter hyper-intensities. Migraine with aura was the only headache type associated with brain infarcts. Evidence that headache of any type by itself or in

  15. Community Based Integrated Intervention, Lesions Learn from Rural Remote Areas of Bangladesh

    International Nuclear Information System (INIS)

    Talukder, Shamim; Farhana, Dina; Shajedul Haque, Haque; Maruf, Kazi

    2014-01-01

    health and nutrition, special emphasis was given at the WVB project activities. However, projects had great impact on behavior change components and mothers’ knowledge on basic concepts of nutrition has increased vastly, doesn’t effect on reducing severe and moderate malnutrition. The proportions of mildly under nourished children were underweight (30.2%), stunted (29.3%) and wasted (22.8%). The proportions of children being moderately under nourished were underweight (29.6%), stunted (19.9%) and wasted (24.1%). Indeed progress of achieving severe malnutrition, wasting has decreased drastically to 8% which was 17% in the baseline, however, severe underweight and stunting increased compared to baseline and also slightly higher compare to national data. Access in taking services have increased and among the children suffering from Diarrhea, 92.9% treated by the nearest facilities. Among the children eligible for vaccination, around 63.3% has reported to be fully immunized. Conclusions: While such community based intervention has impact on changing knowledge and uptake of services, limited in reducing acute malnutrition indeed. So, nutrition intervention redesign is necessary and food supplementation as well as treatment of acute malnourished children should be prioritized. (author)

  16. Chemical shift MRI can aid in the diagnosis of indeterminate skeletal lesions of the spine

    Energy Technology Data Exchange (ETDEWEB)

    Douis, H. [University Hospital Birmingham, Department of Radiology, Birmingham (United Kingdom); Royal Orthopaedic Hospital, Department of Radiology, Birmingham (United Kingdom); Davies, A.M. [Royal Orthopaedic Hospital, Department of Radiology, Birmingham (United Kingdom); Jeys, L. [Royal Orthopaedic Hospital, Department of Orthopaedic Oncology, Birmingham (United Kingdom); Sian, P. [Royal Orthopaedic Hospital, Department of Spinal Surgery and Spinal Oncology, Birmingham (United Kingdom)

    2016-04-15

    To evaluate the role of chemical shift MRI in the characterisation of indeterminate skeletal lesions of the spine as benign or malignant. Fifty-five patients (mean age 54.7 years) with 57 indeterminate skeletal lesions of the spine were included in this retrospective study. In addition to conventional MRI at 3 T which included at least sagittal T1WI and T2WI/STIR sequences, patients underwent chemical shift MRI. A cut-off value with a signal drop-out of 20 % was used to differentiate benign lesions from malignant lesions (signal drop-out <20 % being malignant). There were 45 benign lesions and 12 malignant lesions. Chemical shift imaging correctly diagnosed 33 of 45 lesions as benign and 11 of 12 lesions as malignant. In contrast, there were 12 false positive cases and 1 false negative case based on chemical shift MRI. This yielded a sensitivity of 91.7 %, a specificity of 73.3 %, a negative predictive value of 97.1 %, a positive predictive value of 47.8 % and a diagnostic accuracy of 82.5 %. Chemical shift MRI can aid in the characterisation of indeterminate skeletal lesions of the spine in view of its high sensitivity in diagnosing malignant lesions. Chemical shift MRI can potentially avoid biopsy in a considerable percentage of patients with benign skeletal lesions of the spine. (orig.)

  17. Hock lesions and free-stall design.

    Science.gov (United States)

    Weary, D M; Taszkun, I

    2000-04-01

    We compared the prevalence and severity of skin lesions on the hocks of lactating dairy cows in southern British Columbia, comparing 20 farms using three common bedding surfaces: sawdust, sand, and geotextile mattresses. Skin lesions were scored at five positions on the hock. For each position we noted if the lesion showed inflammatory attributes, and then assigned a severity score. Of the 1752 lactating cows scored, 1267 cows (73%) had at least one hock lesion. Of those cows with lesions, 87% had lesions on both legs, 76% had lesions on more than one location on the hock, and 78% had a lesion of at least moderate severity (i.e., evidence of skin breakage or an area of hair loss >10 cm2). Lesions were most prevalent on farms that used geotextile mattresses (91% of cows) and least common on farms that used sand (24% of cows). Moreover, lesions on cows from farms using mattresses were more numerous and more severe than those on cows from sand-bedded farms. The prevalence and severity of lesions on farms using sawdust was intermediate. Lesions also varied in relation to location on the hock. For farms using geotextile mattresses, lesions were more common and more severe on the lateral surfaces of both the tuber calcis and the tarsal joint. On farms using sawdust, lesions were common on the dorsal surface of the tuber calcis and the lateral surfaces of both the tuber calcis and the tarsal joint. Lesions were rare on all five positions for cows from sand-bedded farms. Among the 10 farms sampled using sawdust, we found a significant negative relationship between the length of the stall and severity of lesions. For cows with lesions, the number and severity of lesions increased with age.

  18. Multi-probe-based resonance-frequency electrical impedance spectroscopy for detection of suspicious breast lesions: improving performance using partial ROC optimization

    Science.gov (United States)

    Lederman, Dror; Zheng, Bin; Wang, Xingwei; Wang, Xiao Hui; Gur, David

    2011-03-01

    We have developed a multi-probe resonance-frequency electrical impedance spectroscope (REIS) system to detect breast abnormalities. Based on assessing asymmetry in REIS signals acquired between left and right breasts, we developed several machine learning classifiers to classify younger women (i.e., under 50YO) into two groups of having high and low risk for developing breast cancer. In this study, we investigated a new method to optimize performance based on the area under a selected partial receiver operating characteristic (ROC) curve when optimizing an artificial neural network (ANN), and tested whether it could improve classification performance. From an ongoing prospective study, we selected a dataset of 174 cases for whom we have both REIS signals and diagnostic status verification. The dataset includes 66 "positive" cases recommended for biopsy due to detection of highly suspicious breast lesions and 108 "negative" cases determined by imaging based examinations. A set of REIS-based feature differences, extracted from the two breasts using a mirror-matched approach, was computed and constituted an initial feature pool. Using a leave-one-case-out cross-validation method, we applied a genetic algorithm (GA) to train the ANN with an optimal subset of features. Two optimization criteria were separately used in GA optimization, namely the area under the entire ROC curve (AUC) and the partial area under the ROC curve, up to a predetermined threshold (i.e., 90% specificity). The results showed that although the ANN optimized using the entire AUC yielded higher overall performance (AUC = 0.83 versus 0.76), the ANN optimized using the partial ROC area criterion achieved substantially higher operational performance (i.e., increasing sensitivity level from 28% to 48% at 95% specificity and/ or from 48% to 58% at 90% specificity).

  19. Providing Databases for Different Indoor Positioning Technologies: Pros and Cons of Magnetic Field and Wi-Fi Based Positioning

    Directory of Open Access Journals (Sweden)

    Joaquín Torres-Sospedra

    2016-01-01

    Full Text Available Localization is one of the main pillars for indoor services. However, it is still very difficult for the mobile sensing community to compare state-of-the-art indoor positioning systems due to the scarcity of publicly available databases. To make fair and meaningful comparisons between indoor positioning systems, they must be evaluated in the same situation, or in the same sets of situations. In this paper, two databases are introduced for studying the performance of magnetic field and Wi-Fi fingerprinting based positioning systems in the same environment (i.e., indoor area. The “magnetic” database contains more than 40,000 discrete captures (270 continuous samples, whereas the “Wi-Fi” one contains 1,140 ones. The environment and both databases are fully detailed in this paper. A set of experiments is also presented where two simple but effective baselines have been developed to test the suitability of the databases. Finally, the pros and cons of both types of positioning techniques are discussed in detail.

  20. Improving Wi-Fi Based Indoor Positioning Using Bluetooth Add-Ons

    DEFF Research Database (Denmark)

    Baniukevic, Artur; Sabonis, Dovydas; Jensen, Christian S.

    2011-01-01

    enabling indoor LBSs. Existing indoor positioning services typically use a single technology such as Wi-Fi, RFID or Bluetooth. Wi-Fi based indoor positioning is relatively easy to deploy, but does often not offer good positioning accuracy. In contrast, the use of RFID or Bluetooth for positioning requires...... considerable investments in equipment in order to ensure good positioning accuracy. Motivated by these observations, we propose a hybrid approach to indoor positioning. In particular, we introduce Bluetooth hotspots into an indoor space with an existing Wi-Fi infrastructure such that better positioning...

  1. Impact of analyzing fewer image frames per segment during offline volumetric radiofrequency based intravascular ultrasound measurements of target lesions prior to percutaneous coronary interventions

    NARCIS (Netherlands)

    Huisman, J.; Hartmann, M.; Hartmann, M.; Mintz, G.S.; van Houwelingen, G.K.; Stoel, M.G.; de Man, F.H.; Louwerenburg, H.; von Birgelen, Clemens

    2012-01-01

    In the present study, we evaluated the impact of a 50% reduction in number of image frames (every second frame) on the analysis time and variability of offline volumetric radiofrequency-based intravascular ultrasound (RF-IVUS) measurements in target lesions prior to percutaneous coronary

  2. Zero in the brain: A voxel-based lesion-symptom mapping study in right hemisphere damaged patients.

    Science.gov (United States)

    Benavides-Varela, Silvia; Passarini, Laura; Butterworth, Brian; Rolma, Giuseppe; Burgio, Francesca; Pitteri, Marco; Meneghello, Francesca; Shallice, Tim; Semenza, Carlo

    2016-04-01

    Transcoding numerals containing zero is more problematic than transcoding numbers formed by non-zero digits. However, it is currently unknown whether this is due to zeros requiring brain areas other than those traditionally associated with number representation. Here we hypothesize that transcoding zeros entails visuo-spatial and integrative processes typically associated with the right hemisphere. The investigation involved 22 right-brain-damaged patients and 20 healthy controls who completed tests of reading and writing Arabic numbers. As expected, the most significant deficit among patients involved a failure to cope with zeros. Moreover, a voxel-based lesion-symptom mapping (VLSM) analysis showed that the most common zero-errors were maximally associated to the right insula which was previously related to sensorimotor integration, attention, and response selection, yet for the first time linked to transcoding processes. Error categories involving other digits corresponded to the so-called Neglect errors, which however, constituted only about 10% of the total reading and 3% of the writing mistakes made by the patients. We argue that damage to the right hemisphere impairs the mechanism of parsing, and the ability to set-up empty-slot structures required for processing zeros in complex numbers; moreover, we suggest that the brain areas located in proximity to the right insula play a role in the integration of the information resulting from the temporary application of transcoding procedures. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Classification of hypervascular liver lesions based on hepatic artery and portal vein blood supply coefficients calculated from triphasic CT scans.

    Science.gov (United States)

    Boas, F Edward; Kamaya, Aya; Do, Bao; Desser, Terry S; Beaulieu, Christopher F; Vasanawala, Shreyas S; Hwang, Gloria L; Sze, Daniel Y

    2015-04-01

    Perfusion CT of the liver typically involves scanning the liver at least 20 times, resulting in a large radiation dose. We developed and validated a simplified model of tumor blood supply that can be applied to standard triphasic scans and evaluated whether this can be used to distinguish benign and malignant liver lesions. Triphasic CTs of 46 malignant and 32 benign liver lesions were analyzed. For each phase, regions of interest were drawn in the arterially enhancing portion of each lesion, as well as the background liver, aorta, and portal vein. Hepatic artery and portal vein blood supply coefficients for each lesion were then calculated by expressing the enhancement curve of the lesion as a linear combination of the enhancement curves of the aorta and portal vein. Hepatocellular carcinoma (HCC) and hypervascular metastases, on average, both had increased hepatic artery coefficients compared to the background liver. Compared to HCC, benign lesions, on average, had either a greater hepatic artery coefficient (hemangioma) or a greater portal vein coefficient (focal nodular hyperplasia or transient hepatic attenuation difference). Hypervascularity with washout is a key diagnostic criterion for HCC, but it had a sensitivity of 72 % and specificity of 81 % for diagnosing malignancy in our diverse set of liver lesions. The sensitivity for malignancy was increased to 89 % by including enhancing lesions that were hypodense on all phases. The specificity for malignancy was increased to 97 % (p = 0.039) by also examining hepatic artery and portal vein blood supply coefficients, while maintaining a sensitivity of 76 %.

  4. Anàlisi comparatiu sobre l’efectivitat de la prevenció de lesions entre infantils i cadets en el futbol base masculí

    OpenAIRE

    Basquens Espada, Eric

    2016-01-01

    Els objectius d'aquest treball és conèixer quin tipus de lesions es produeixen en un equip infantil i cadet de futbol base masculí, aplicar un treball preventiu per poder conèixer si existeix una reducció de les lesions mitjançant aquest tipus de treball. I de manera més específica, conèixer la gravetat de les lesions d'aquest edat i conèixer quin grup d'edat en el futbol no es lesiona i perquè. Per poder realitzar aquest treball he utilitzat un grup control, on no realitzaven treball prev...

  5. PET Motion Compensation for Radiation Therapy Using a CT-Based Mid-Position Motion Model: Methodology and Clinical Evaluation

    International Nuclear Information System (INIS)

    Kruis, Matthijs F.; Kamer, Jeroen B. van de; Houweling, Antonetta C.; Sonke, Jan-Jakob; Belderbos, José S.A.; Herk, Marcel van

    2013-01-01

    Purpose: Four-dimensional positron emission tomography (4D PET) imaging of the thorax produces sharper images with reduced motion artifacts. Current radiation therapy planning systems, however, do not facilitate 4D plan optimization. When images are acquired in a 2-minute time slot, the signal-to-noise ratio of each 4D frame is low, compromising image quality. The purpose of this study was to implement and evaluate the construction of mid-position 3D PET scans, with motion compensated using a 4D computed tomography (CT)-derived motion model. Methods and Materials: All voxels of 4D PET were registered to the time-averaged position by using a motion model derived from the 4D CT frames. After the registration the scans were summed, resulting in a motion-compensated 3D mid-position PET scan. The method was tested with a phantom dataset as well as data from 27 lung cancer patients. Results: PET motion compensation using a CT-based motion model improved image quality of both phantoms and patients in terms of increased maximum SUV (SUV max ) values and decreased apparent volumes. In homogenous phantom data, a strong relationship was found between the amplitude-to-diameter ratio and the effects of the method. In heterogeneous patient data, the effect correlated better with the motion amplitude. In case of large amplitudes, motion compensation may increase SUV max up to 25% and reduce the diameter of the 50% SUV max volume by 10%. Conclusions: 4D CT-based motion-compensated mid-position PET scans provide improved quantitative data in terms of uptake values and volumes at the time-averaged position, thereby facilitating more accurate radiation therapy treatment planning of pulmonary lesions

  6. Human brain lesion-deficit inference remapped.

    Science.gov (United States)

    Mah, Yee-Haur; Husain, Masud; Rees, Geraint; Nachev, Parashkev

    2014-09-01

    . Positively, we show that novel machine learning techniques employing high-dimensional inference can nonetheless accurately converge on the true locus. We conclude that current inferences about human brain function and deficits based on lesion mapping must be re-evaluated with methodology that adequately captures the high-dimensional structure of lesion data. © The Author (2014). Published by Oxford University Press on behalf of the Guarantors of Brain.

  7. Multi-scale textural feature extraction and particle swarm optimization based model selection for false positive reduction in mammography.

    Science.gov (United States)

    Zyout, Imad; Czajkowska, Joanna; Grzegorzek, Marcin

    2015-12-01

    The high number of false positives and the resulting number of avoidable breast biopsies are the major problems faced by current mammography Computer Aided Detection (CAD) systems. False positive reduction is not only a requirement for mass but also for calcification CAD systems which are currently deployed for clinical use. This paper tackles two problems related to reducing the number of false positives in the detection of all lesions and masses, respectively. Firstly, textural patterns of breast tissue have been analyzed using several multi-scale textural descriptors based on wavelet and gray level co-occurrence matrix. The second problem addressed in this paper is the parameter selection and performance optimization. For this, we adopt a model selection procedure based on Particle Swarm Optimization (PSO) for selecting the most discriminative textural features and for strengthening the generalization capacity of the supervised learning stage based on a Support Vector Machine (SVM) classifier. For evaluating the proposed methods, two sets of suspicious mammogram regions have been used. The first one, obtained from Digital Database for Screening Mammography (DDSM), contains 1494 regions (1000 normal and 494 abnormal samples). The second set of suspicious regions was obtained from database of Mammographic Image Analysis Society (mini-MIAS) and contains 315 (207 normal and 108 abnormal) samples. Results from both datasets demonstrate the efficiency of using PSO based model selection for optimizing both classifier hyper-parameters and parameters, respectively. Furthermore, the obtained results indicate the promising performance of the proposed textural features and more specifically, those based on co-occurrence matrix of wavelet image representation technique. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Imaging inflammatory acne: lesion detection and tracking

    Science.gov (United States)

    Cula, Gabriela O.; Bargo, Paulo R.; Kollias, Nikiforos

    2010-02-01

    It is known that effectiveness of acne treatment increases when the lesions are detected earlier, before they could progress into mature wound-like lesions, which lead to scarring and discoloration. However, little is known about the evolution of acne from early signs until after the lesion heals. In this work we computationally characterize the evolution of inflammatory acne lesions, based on analyzing cross-polarized images that document acne-prone facial skin over time. Taking skin images over time, and being able to follow skin features in these images present serious challenges, due to change in the appearance of skin, difficulty in repositioning the subject, involuntary movement such as breathing. A computational technique for automatic detection of lesions by separating the background normal skin from the acne lesions, based on fitting Gaussian distributions to the intensity histograms, is presented. In order to track and quantify the evolution of lesions, in terms of the degree of progress or regress, we designed a study to capture facial skin images from an acne-prone young individual, followed over the course of 3 different time points. Based on the behavior of the lesions between two consecutive time points, the automatically detected lesions are classified in four categories: new lesions, resolved lesions (i.e. lesions that disappear completely), lesions that are progressing, and lesions that are regressing (i.e. lesions in the process of healing). The classification our methods achieve correlates well with visual inspection of a trained human grader.

  9. The Impact of Diffusion Tensor Imaging Fiber Tracking of the Corticospinal Tract Based on Navigated Transcranial Magnetic Stimulation on Surgery of Motor-Eloquent Brain Lesions.

    Science.gov (United States)

    Raffa, Giovanni; Conti, Alfredo; Scibilia, Antonino; Cardali, Salvatore Massimiliano; Esposito, Felice; Angileri, Filippo Flavio; La Torre, Domenico; Sindorio, Carmela; Abbritti, Rosaria Viola; Germanò, Antonino; Tomasello, Francesco

    2017-11-29

    Navigated transcranial magnetic stimulation (nTMS) enables preoperative mapping of the motor cortex (M1). The combination of nTMS with diffusion tensor imaging fiber tracking (DTI-FT) of the corticospinal tract (CST) has been described; however, its impact on surgery of motor-eloquent lesions has not been addressed. To analyze the impact of nTMS-based mapping on surgery of motor-eloquent lesions. In this retrospective case-control study, we reviewed the data of patients operated for suspected motor-eloquent lesions between 2012 and 2015. The patients underwent nTMS mapping of M1 and, from 2014, nTMS-based DTI-FT of the CST. The impact on the preoperative risk/benefit analysis, surgical strategy, craniotomy size, extent of resection (EOR), and outcome were compared with a control group. We included 35 patients who underwent nTMS mapping of M1 (group A), 35 patients who also underwent nTMS-based DTI-FT of the CST (group B), and a control group composed of 35 patients treated without nTMS (group C). The patients in groups A and B received smaller craniotomies (P = .01; P = .001), had less postoperative seizures (P = .02), and a better postoperative motor performance (P = .04) and Karnofsky Performance Status (P = .009) than the controls. Group B exhibited an improved risk/benefit analysis (P = .006), an increased EOR of nTMS-negative lesions in absence of preoperative motor deficits (P = .01), and less motor and Karnofsky Performance Status worsening in case of preoperative motor deficits (P = .02, P = .03) than group A. nTMS-based mapping enables a tailored surgical approach for motor-eloquent lesions. It may improve the risk/benefit analysis, EOR and outcome, particularly when nTMS-based DTI-FT is performed. Copyright © 2017 by the Congress of Neurological Surgeons

  10. Selective lesion of septal cholinergic neurons in rats impairs acquisition of a delayed matching to position T-maze task by delaying the shift from a response to a place strategy.

    Science.gov (United States)

    Fitz, Nicholas F; Gibbs, Robert B; Johnson, David A

    2008-12-16

    This study tested the hypothesis that septal cholinergic lesions impair acquisition of a delayed matching to position (DMP) T-maze task in male rats by affecting learning strategy. Rats received either the selective cholinergic immunotoxin, 192 IgG-saporin (SAP) or artificial cerebrospinal fluid directly into the medial septum. Two weeks later, animals were trained to acquire the DMP task. SAP-treated rats took significantly longer to acquire the task than corresponding controls. Both SAP-treated and control rats adopted a persistent turn and utilized a response strategy during early periods of training. By the time rats reached criterion the persistent turn was no longer evident, and all rats had shifted to an allocentric strategy, i.e., were relying on extramaze cues to a significant degree. During the acquisition period, SAP-treated rats spent significantly more days showing a persistent turn and using a response strategy than corresponding controls. The added time spent using a response strategy accounted entirely for the added days required to reach criterion among the SAP-treated rats. This suggests that the principal mechanism by which septal cholinergic lesions impair DMP acquisition in male rats is by increasing the predisposition to use a response vs. a place strategy, thereby affecting the ability to switch from one strategy to another.

  11. Visualization of small lesions in rat cartilage by means of laboratory-based x-ray phase contrast imaging

    Science.gov (United States)

    Marenzana, Massimo; Hagen, Charlotte K.; Das Neves Borges, Patricia; Endrizzi, Marco; Szafraniec, Magdalena B.; Ignatyev, Konstantin; Olivo, Alessandro

    2012-12-01

    Being able to quantitatively assess articular cartilage in three-dimensions (3D) in small rodent animal models, with a simple laboratory set-up, would prove extremely important for the development of pre-clinical research focusing on cartilage pathologies such as osteoarthritis (OA). These models are becoming essential tools for the development of new drugs for OA, a disease affecting up to 1/3 of the population older than 50 years for which there is no cure except prosthetic surgery. However, due to limitations in imaging technology, high-throughput 3D structural imaging has not been achievable in small rodent models, thereby limiting their translational potential and their efficiency as research tools. We show that a simple laboratory system based on coded-aperture x-ray phase contrast imaging (CAXPCi) can correctly visualize the cartilage layer in slices of an excised rat tibia imaged both in air and in saline solution. Moreover, we show that small, surgically induced lesions are also correctly detected by the CAXPCi system, and we support this finding with histopathology examination. Following these successful proof-of-concept results in rat cartilage, we expect that an upgrade of the system to higher resolutions (currently underway) will enable extending the method to the imaging of mouse cartilage as well. From a technological standpoint, by showing the capability of the system to detect cartilage also in water, we demonstrate phase sensitivity comparable to other lab-based phase methods (e.g. grating interferometry). In conclusion, CAXPCi holds a strong potential for being adopted as a routine laboratory tool for non-destructive, high throughput assessment of 3D structural changes in murine articular cartilage, with a possible impact in the field similar to the revolution that conventional microCT brought into bone research.

  12. The impact of sensor errors and building structures on particle filter-based inertial positioning

    DEFF Research Database (Denmark)

    Toftkjær, Thomas; Kjærgaard, Mikkel Baun

    2012-01-01

    Positioning systems that do not depend on in-building infrastructures are critical for enabling a range of applications within pervasive computing. Particle filter-based inertial positioning promises infrastructure-less positioning, but previous research has not provided an understanding of how t...

  13. Pulmonary lesion induced by low and high positive end-expiratory pressure levels during protective ventilation in experimental acute lung injury.

    Science.gov (United States)

    Pássaro, Caroline P; Silva, Pedro L; Rzezinski, Andréia F; Abrantes, Simone; Santiago, Viviane R; Nardelli, Liliane; Santos, Raquel S; Barbosa, Carolina M L; Morales, Marcelo M; Zin, Walter A; Amato, Marcelo B P; Capelozzi, Vera L; Pelosi, Paolo; Rocco, Patricia R M

    2009-03-01

    To investigate the effects of low and high levels of positive end-expiratory pressure (PEEP), without recruitment maneuvers, during lung protective ventilation in an experimental model of acute lung injury (ALI). Prospective, randomized, and controlled experimental study. University research laboratory. Wistar rats were randomly assigned to control (C) [saline (0.1 mL), intraperitoneally] and ALI [paraquat (15 mg/kg), intraperitoneally] groups. After 24 hours, each group was further randomized into four groups (six rats each) at different PEEP levels = 1.5, 3, 4.5, or 6 cm H2O and ventilated with a constant tidal volume (6 mL/kg) and open thorax. Lung mechanics [static elastance (Est, L) and viscoelastic pressure (DeltaP2, L)] and arterial blood gases were measured before (Pre) and at the end of 1-hour mechanical ventilation (Post). Pulmonary histology (light and electron microscopy) and type III procollagen (PCIII) messenger RNA (mRNA) expression were measured after 1 hour of mechanical ventilation. In ALI group, low and high PEEP levels induced a greater percentage of increase in Est, L (44% and 50%) and DeltaP2, L (56% and 36%) in Post values related to Pre. Low PEEP yielded alveolar collapse whereas high PEEP caused overdistension and atelectasis, with both levels worsening oxygenation and increasing PCIII mRNA expression. In the present nonrecruited ALI model, protective mechanical ventilation with lower and higher PEEP levels than required for better oxygenation increased Est, L and DeltaP2, L, the amount of atelectasis, and PCIII mRNA expression. PEEP selection titrated for a minimum elastance and maximum oxygenation may prevent lung injury while deviation from these settings may be harmful.

  14. Ground-Based Global Positioning System (GPS) Meteorology Integrated Precipitable Water Vapor (IPW)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ground-Based Global Positioning System (GPS) Meteorology Integrated Precipitable Water Vapor (IPW) data set measures atmospheric water vapor using ground-based...

  15. Fusion Based on Visible Light Positioning and Inertial Navigation Using Extended Kalman Filters.

    Science.gov (United States)

    Li, Zhitian; Feng, Lihui; Yang, Aiying

    2017-05-11

    With the rapid development of smart technology, the need for location-based services (LBS) increases every day. Since classical positioning technology such as GPS cannot satisfy the needs of indoor positioning, new indoor positioning technologies, such as Bluetooth, Wi-Fi, and Visible light communication (VLC), have already cut a figure. VLC positioning has been proposed because it has higher accuracy, costs less, and is easier to accomplish in comparison to the other indoor positioning technologies. However, the practicality of VLC positioning is limited since it is easily affected by multipath effects and the layout of LEDs. Thus, we propose a fusion positioning system based on extended Kalman filters, which can fuse the VLC position and the inertial navigation data. The accuracy of the fusion positioning system is in centimeters, which is better compared to the VLC-based positioning or inertial navigation alone. Furthermore, the fusion positioning system has high accuracy, saves energy, costs little, and is easy to install, making it a promising candidate for future indoor positioning applications.

  16. Performance comparison of deep learning and segmentation-based radiomic methods in the task of distinguishing benign and malignant breast lesions on DCE-MRI

    Science.gov (United States)

    Antropova, Natasha; Huynh, Benjamin; Giger, Maryellen

    2017-03-01

    Intuitive segmentation-based CADx/radiomic features, calculated from the lesion segmentations of dynamic contrast-enhanced magnetic resonance images (DCE-MRIs) have been utilized in the task of distinguishing between malignant and benign lesions. Additionally, transfer learning with pre-trained deep convolutional neural networks (CNNs) allows for an alternative method of radiomics extraction, where the features are derived directly from the image data. However, the comparison of computer-extracted segmentation-based and CNN features in MRI breast lesion characterization has not yet been conducted. In our study, we used a DCE-MRI database of 640 breast cases - 191 benign and 449 malignant. Thirty-eight segmentation-based features were extracted automatically using our quantitative radiomics workstation. Also, 2D ROIs were selected around each lesion on the DCE-MRIs and directly input into a pre-trained CNN AlexNet, yielding CNN features. Each method was investigated separately and in combination in terms of performance in the task of distinguishing between benign and malignant lesions. Area under the ROC curve (AUC) served as the figure of merit. Both methods yielded promising classification performance with round-robin cross-validated AUC values of 0.88 (se =0.01) and 0.76 (se=0.02) for segmentationbased and deep learning methods, respectively. Combination of the two methods enhanced the performance in malignancy assessment resulting in an AUC value of 0.91 (se=0.01), a statistically significant improvement over the performance of the CNN method alone.

  17. A COMPARATIVE ANALYSIS OF GLOBAL POSITIONING SYSTEM SCHEMES BASED ON BLOCK CODES

    OpenAIRE

    Prasad Janga; Dr. R. L. Sharma

    2017-01-01

    Global Positioning System (GPS) is a satellite based positioning system based on radio ranging technique. The GPS will provide very accurate three-dimensional position, velocity and timing information to users anywhere in the world. GPS can also be used in other applications such as vehicle monitoring for traffic management in urban areas, Geographical Information System (GIS), 4G Communications, marine navigation, search and rescue and military applications. As GPS accuracy is limited by ion...

  18. Positioning of aquatic animals based on time-of-arrival and random walk models using YAPS (Yet Another Positioning Solver)

    DEFF Research Database (Denmark)

    Baktoft, Henrik; Gjelland, Karl Øystein; Økland, Finn

    2017-01-01

    Aquatic positional telemetry offers vast opportunities to study in vivo behaviour of wild animals, but there is room for improvement in the data quality provided by current procedures for estimating positions. Here we present a novel positioning method called YAPS (Yet Another Positioning Solver...

  19. Toward a non-invasive screening tool for differentiation of pancreatic lesions based on intra-voxel incoherent motion derived parameters

    Energy Technology Data Exchange (ETDEWEB)

    Graf, Markus; Simon, Dirk; Mang, Sarah [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Software Development for Integrated Therapy and Diagnostics; Lemke, Andreas [Heidelberg Univ., Mannheim (Germany). Dept. of Computer Assisted Clinical Medicine; Gruenberg, Katharina [Deutsches Krebsforschungszentrum (DKFZ), Heidelberg (Germany). Dept. of Radiology

    2013-03-01

    Early recognition of and differential diagnosis between pancreatic cancer and chronic pancreatitis is an important step in successful therapy. Parameters of the IVIM (intra-voxel incoherent motion) theory can be used to differentiate between those lesions. The objective of this work is to evaluate the effects of rigid image registration on IVIM derived parameters for differentiation of pancreatic lesions such as pancreatic cancer and solid mass forming pancreatitis. The effects of linear image registration methods on reproducibility and accuracy of IVIM derived parameters were quantified on MR images of ten volunteers. For this purpose, they were evaluated statistically by comparison of registered and unregistered parameter data. Further, the perfusion fraction f was used to differentiate pancreatic lesions on eleven previously diagnosed patient data sets. Its diagnostic power with and without rigid registration was evaluated using receiver operating curves (ROC) analysis. The pancreas was segmented manually on MR data sets of healthy volunteers as well as the patients showing solid pancreatic lesions. Diffusion weighted imaging was performed in 10 blocks of breath-hold phases. Linear registration of the weighted image stack leads to a 3.7% decrease in variability of the IVIM derived parameter f due to an improved anatomical overlap of 5%. Consequently, after registration the area under the curve in the ROC-analysis for the differentiation approach increased by 2.7%. In conclusion, rigid registration improves the differentiation process based on f-values. (orig.)

  20. Toward a non-invasive screening tool for differentiation of pancreatic lesions based on intra-voxel incoherent motion derived parameters

    International Nuclear Information System (INIS)

    Graf, Markus; Simon, Dirk; Mang, Sarah; Lemke, Andreas; Gruenberg, Katharina

    2013-01-01

    Early recognition of and differential diagnosis between pancreatic cancer and chronic pancreatitis is an important step in successful therapy. Parameters of the IVIM (intra-voxel incoherent motion) theory can be used to differentiate between those lesions. The objective of this work is to evaluate the effects of rigid image registration on IVIM derived parameters for differentiation of pancreatic lesions such as pancreatic cancer and solid mass forming pancreatitis. The effects of linear image registration methods on reproducibility and accuracy of IVIM derived parameters were quantified on MR images of ten volunteers. For this purpose, they were evaluated statistically by comparison of registered and unregistered parameter data. Further, the perfusion fraction f was used to differentiate pancreatic lesions on eleven previously diagnosed patient data sets. Its diagnostic power with and without rigid registration was evaluated using receiver operating curves (ROC) analysis. The pancreas was segmented manually on MR data sets of healthy volunteers as well as the patients showing solid pancreatic lesions. Diffusion weighted imaging was performed in 10 blocks of breath-hold phases. Linear registration of the weighted image stack leads to a 3.7% decrease in variability of the IVIM derived parameter f due to an improved anatomical overlap of 5%. Consequently, after registration the area under the curve in the ROC-analysis for the differentiation approach increased by 2.7%. In conclusion, rigid registration improves the differentiation process based on f-values. (orig.)

  1. Maxillary Bone Regeneration Based on Nanoreservoirs Functionalized ε-Polycaprolactone Biomembranes in a Mouse Model of Jaw Bone Lesion

    Directory of Open Access Journals (Sweden)

    Marion Strub

    2018-01-01

    Full Text Available Current approaches of regenerative therapies constitute strategies for bone tissue reparation and engineering, especially in the context of genetical diseases with skeletal defects. Bone regeneration using electrospun nanofibers’ implant has the following objectives: bone neoformation induction with rapid healing, reduced postoperative complications, and improvement of bone tissue quality. In vivo implantation of polycaprolactone (PCL biomembrane functionalized with BMP-2/Ibuprofen in mouse maxillary defects was followed by bone neoformation kinetics evaluation using microcomputed tomography. Wild-Type (WT and Tabby (Ta mice were used to compare effects on a normal phenotype and on a mutant model of ectodermal dysplasia (ED. After 21 days, no effect on bone neoformation was observed in Ta treated lesion (4% neoformation compared to 13% in the control lesion. Between the 21st and the 30th days, the use of biomembrane functionalized with BMP-2/Ibuprofen in maxillary bone lesions allowed a significant increase in bone neoformation peaks (resp., +8% in mutant Ta and +13% in WT. Histological analyses revealed a neoformed bone with regular trabecular structure, areas of mineralized bone inside the membrane, and an improved neovascularization in the treated lesion with bifunctionalized membrane. In conclusion, PCL functionalized biomembrane promoted bone neoformation, this effect being modulated by the Ta bone phenotype responsible for an alteration of bone response.

  2. Multicenter assessment of the reproducibility of volumetric radiofrequency-based intravascular ultrasound measurements in coronary lesions that were consecutively stented

    NARCIS (Netherlands)

    Huisman, Jeroen; Egede, R.; Rdzanek, A.; Böse, D.; Erbel, R.; van der Palen, Jacobus Adrianus Maria; von Birgelen, Clemens

    2012-01-01

    To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility

  3. Automated segmentation of ultrasonic breast lesions using statistical texture classification and active contour based on probability distance.

    Science.gov (United States)

    Liu, Bo; Cheng, H D; Huang, Jianhua; Tian, Jiawei; Liu, Jiafeng; Tang, Xianglong

    2009-08-01

    Because of its complicated structure, low signal/noise ratio, low contrast and blurry boundaries, fully automated segmentation of a breast ultrasound (BUS) image is a difficult task. In this paper, a novel segmentation method for BUS images without human intervention is proposed. Unlike most published approaches, the proposed method handles the segmentation problem by using a two-step strategy: ROI generation and ROI segmentation. First, a well-trained texture classifier categorizes the tissues into different classes, and the background knowledge rules are used for selecting the regions of interest (ROIs) from them. Second, a novel probability distance-based active contour model is applied for segmenting the ROIs and finding the accurate positions of the breast tumors. The active contour model combines both global statistical information and local edge information, using a level set approach. The proposed segmentation method was performed on 103 BUS images (48 benign and 55 malignant). To validate the performance, the results were compared with the corresponding tumor regions marked by an experienced radiologist. Three error metrics, true-positive ratio (TP), false-negative ratio (FN) and false-positive ratio (FP) were used for measuring the performance of the proposed method. The final results (TP = 91.31%, FN = 8.69% and FP = 7.26%) demonstrate that the proposed method can segment BUS images efficiently, quickly and automatically.

  4. RADIODIAGNOSIS OF PLEURAL LESIONS WITH USG AND CT SCAN

    Directory of Open Access Journals (Sweden)

    Bheemashanker

    2017-09-01

    Full Text Available BACKGROUND Ultrasound is easy available, less expensive study. It differentiates pleural effusion, consolidation and masses. CT scores in diagnosing early pleural lesions and helps in localising lesions differentiating benign and malignant. The aim of the study is to- 1. Assess the value of ultrasonography and computed tomography in evaluation of pleural lesions. 2. Determine the sensitivity and specificity of ultrasound and CT in pleural lesions. MATERIALS AND METHODS The present study was aimed at assessing the value of ultrasonography and CT in evaluating the pleural lesions. In our study, during the period of 12 months, 100 patients with pleural effusions were evaluated. The most common cause was transudate. Exudates consist of malignant and non-malignant causes. RESULTS The study group was defined into two groups- Malignant and non-malignant group based on pleural effusion of transudate and exudate types. CT and ultrasound has success rate of 100% and 85% respectively to identify neoplastic and non-neoplastic disease. Diagnostic accuracy of CT and ultrasound are comparable while CT scores over ultrasound in failed cases. CT has 100% sensitivity and 100% specificity in pleural lesions. CT has more therapeutic value compared to ultrasound. CONCLUSION The role of ultrasound and CT are complimentary, give high yield of positive results for pleural mass differentiation; useful for guided procedures like pleural biopsy and pleural drainage. Combined study not only useful for localisation of lesion, but also gives information about the extent of disease and characterising the tissue density by analysis of attenuation coefficient.

  5. Infection with CagA-positive Helicobacter pylori strain containing three EPIYA C phosphorylation sites is associated with more severe gastric lesions in experimentally infected Mongolian gerbils (Meriones unguiculatus).

    Science.gov (United States)

    Ferreira Júnior, M; Batista, S A; Vidigal, P V T; Cordeiro, A A C; Oliveira, F M S; Prata, L O; Diniz, A E T; Barral, C M; Barbuto, R C; Gomes, A D; Araújo, I D; Queiroz, D M M; Caliari, M V

    2015-04-27

    Infection with Helicobacter pylori strains containing high number of EPIYA-C phosphorylation sites in the CagA is associated with significant gastritis and increased risk of developing pre-malignant gastric lesions and gastric carcinoma. However, these findings have not been reproduced in animal models yet. Therefore, we investigated the effect on the gastric mucosa of Mongolian gerbil (Meriones unguiculatus) infected with CagA-positive H. pylori strains exhibiting one or three EPIYA-C phosphorilation sites. Mongolian gerbils were inoculated with H. pylori clonal isolates containing one or three EPIYA-C phosphorylation sites. Control group was composed by uninfected animals challenged with Brucella broth alone. Gastric fragments were evaluated by the modified Sydney System and digital morphometry. Clonal relatedness between the isolates was considered by the identical RAPD-PCR profiles and sequencing of five housekeeping genes, vacA i/d region and of oipA. The other virulence markers were present in both isolates (vacA s1i1d1m1, iceA2, and intact dupA). CagA of both isolates was translocated and phosphorylated in AGS cells. After 45 days of infection, there was a significant increase in the number of inflammatory cells and in the area of the lamina propria in the infected animals, notably in those infected by the CagA-positive strain with three EPIYA-C phosphorylation sites. After six months of infection, a high number of EPIYA-C phosphorylation sites was associated with progressive increase in the intensity of gastritis and in the area of the lamina propria. Atrophy, intestinal metaplasia, and dysplasia were also observed more frequently in animals infected with the CagA-positive isolate with three EPIYA-C sites.  We conclude that infection with H. pylori strain carrying a high number of CagA EPIYA-C phosphorylation sites is associated with more severe gastric lesions in an animal model of H. pylori infection.

  6. Infection with CagA-positive Helicobacter pylori strain containing three EPIYA C phosphorylation sites is associated with more severe gastric lesions in experimentally infected Mongolian gerbils (Meriones unguiculatus

    Directory of Open Access Journals (Sweden)

    M. Ferreira Júnior

    2015-04-01

    Full Text Available Infection with Helicobacter pylori strains containing high number of EPIYA-C phosphorylation sites in the CagA is associated with significant gastritis and increased risk of developing pre-malignant gastric lesions and gastric carcinoma. However, these findings have not been reproduced in animal models yet. Therefore, we investigated the effect on the gastric mucosa of Mongolian gerbil (Meriones unguiculatus infected with CagA-positive H. pylori strains exhibiting one or three EPIYA-C phosphorilation sites. Mongolian gerbils were inoculated with H. pylori clonal isolates containing one or three EPIYA-C phosphorylation sites. Control group was composed by uninfected animals challenged with Brucella broth alone. Gastric fragments were evaluated by the modified Sydney System and digital morphometry. Clonal relatedness between the isolates was considered by the identical RAPD-PCR profiles and sequencing of five housekeeping genes, vacA i/d region and of oipA. The other virulence markers were present in both isolates (vacA s1i1d1m1, iceA2, and intact dupA. CagA of both isolates was translocated and phosphorylated in AGS cells. After 45 days of infection, there was a significant increase in the number of inflammatory cells and in the area of the lamina propria in the infected animals, notably in those infected by the CagA-positive strain with three EPIYA-C phosphorylation sites. After six months of infection, a high number of EPIYA-C phosphorylation sites was associated with progressive increase in the intensity of gastritis and in the area of the lamina propria. Atrophy, intestinal metaplasia, and dysplasia were also observed more frequently in animals infected with the CagA-positive isolate with three EPIYA-C sites.  We conclude that infection with H. pylori strain carrying a high number of CagA EPIYA-C phosphorylation sites is associated with more severe gastric lesions in an animal model of H. pylori infection.

  7. RFID-Based Vehicle Positioning and Its Applications in Connected Vehicles

    Science.gov (United States)

    Wang, Jianqiang; Ni, Daiheng; Li, Keqiang

    2014-01-01

    This paper proposed an RFID-based vehicle positioning approach to facilitate connected vehicles applications. When a vehicle passes over an RFID tag, the vehicle position is given by the accurate position stored in the tag. At locations without RFID coverage, the vehicle position is estimated from the most recent tag location using a kinematics integration algorithm till updates from the next tag. The accuracy of RFID positioning is verified empirically in two independent ways with one using radar and the other a photoelectric switch. The former is designed to verify whether the dynamic position obtained from RFID tags matches the position measured by radar that is regarded as accurate. The latter aims to verify whether the position estimated from the kinematics integration matches the position obtained from RFID tags. Both means supports the accuracy of RFID-based positioning. As a supplement to GPS which suffers from issues such as inaccuracy and loss of signal, RFID positioning is promising in facilitating connected vehicles applications. Two conceptual applications are provided here with one in vehicle operational control and the other in Level IV intersection control. PMID:24599188

  8. RFID-Based Vehicle Positioning and Its Applications in Connected Vehicles

    Directory of Open Access Journals (Sweden)

    Jianqiang Wang

    2014-03-01

    Full Text Available This paper proposed an RFID-based vehicle positioning approach to facilitate connected vehicles applications. When a vehicle passes over an RFID tag, the vehicle position is given by the accurate position stored in the tag. At locations without RFID coverage, the vehicle position is estimated from the most recent tag location using a kinematics integration algorithm till updates from the next tag. The accuracy of RFID positioning is verified empirically in two independent ways with one using radar and the other a photoelectric switch. The former is designed to verify whether the dynamic position obtained from RFID tags matches the position measured by radar that is regarded as accurate. The latter aims to verify whether the position estimated from the kinematics integration matches the position obtained from RFID tags. Both means supports the accuracy of RFID-based positioning. As a supplement to GPS which suffers from issues such as inaccuracy and loss of signal, RFID positioning is promising in facilitating connected vehicles applications. Two conceptual applications are provided here with one in vehicle operational control and the other in Level IV intersection control.

  9. RFID-based vehicle positioning and its applications in connected vehicles.

    Science.gov (United States)

    Wang, Jianqiang; Ni, Daiheng; Li, Keqiang

    2014-03-04

    This paper proposed an RFID-based vehicle positioning approach to facilitate connected vehicles applications. When a vehicle passes over an RFID tag, the vehicle position is given by the accurate position stored in the tag. At locations without RFID coverage, the vehicle position is estimated from the most recent tag location using a kinematics integration algorithm till updates from the next tag. The accuracy of RFID positioning is verified empirically in two independent ways with one using radar and the other a photoelectric switch. The former is designed to verify whether the dynamic position obtained from RFID tags matches the position measured by radar that is regarded as accurate. The latter aims to verify whether the position estimated from the kinematics integration matches the position obtained from RFID tags. Both means supports the accuracy of RFID-based positioning. As a supplement to GPS which suffers from issues such as inaccuracy and loss of signal, RFID positioning is promising in facilitating connected vehicles applications. Two conceptual applications are provided here with one in vehicle operational control and the other in Level IV intersection control.

  10. Ultra-low-dose lung screening CT with model-based iterative reconstruction: an assessment of image quality and lesion conspicuity.

    Science.gov (United States)

    Ju, Yun Hye; Lee, Geewon; Lee, Ji Won; Hong, Seung Baek; Suh, Young Ju; Jeong, Yeon Joo

    2018-05-01

    Background Reducing radiation dose inevitably increases image noise, and thus, it is important in low-dose computed tomography (CT) to maintain image quality and lesion detection performance. Purpose To assess image quality and lesion conspicuity of ultra-low-dose CT with model-based iterative reconstruction (MBIR) and to determine a suitable protocol for lung screening CT. Material and Methods A total of 120 heavy smokers underwent lung screening CT and were randomly and equally assigned to one of five groups: group 1 = 120 kVp, 25 mAs, with FBP reconstruction; group 2 = 120 kVp, 10 mAs, with MBIR; group 3 = 100 kVp, 15 mAs, with MBIR; group 4 = 100 kVp, 10 mAs, with MBIR; and group 5 = 100 kVp, 5 mAs, with MBIR. Two radiologists evaluated intergroup differences with respect to radiation dose, image noise, image quality, and lesion conspicuity using the Kruskal-Wallis test and the Chi-square test. Results Effective doses were 61-87% lower in groups 2-5 than in group 1. Image noises in groups 1 and 5 were significantly higher than in the other groups ( P image quality was best in group 1, but diagnostic acceptability of overall image qualities in groups 1-3 was not significantly different (all P values > 0.05). Lesion conspicuities were similar in groups 1-4, but were significantly poorer in group 5. Conclusion Lung screening CT with MBIR obtained at 100 kVp and 15 mAs enables a ∼60% reduction in radiation dose versus low-dose CT, while maintaining image quality and lesion conspicuity.

  11. Periapical and endodontic status scale based on periapical bone lesions and endodontic treatment quality evaluation using cone-beam computed tomography.

    Science.gov (United States)

    Venskutonis, Tadas; Plotino, Gianluca; Tocci, Luigi; Gambarini, Gianluca; Maminskas, Julius; Juodzbalys, Gintaras

    2015-02-01

    The purpose of this study was to present a new periapical and endodontic status scale (PESS) that is based on the complex periapical index (COPI), which was designed for the identification and classification of periapical bone lesions in cases of apical periodontitis, and the endodontically treated tooth index, which was designed for endodontic treatment quality evaluation by means of cone-beam computed tomographic (CBCT) analysis. Periapical and endodontic status parameters were selected from the already known indexes and scientific literature for radiologic evaluation. Radiographic images (CBCT imaging, digital orthopantomography [DOR], and digital periapical radiography) from 55 patients were analyzed. All parameters were evaluated on CBCT, DOR, and digital periapical radiographic images by 2 external observers. The statistical analysis was performed with software SPSS version 19.0 (SPSS Inc, Chicago, IL). Chi-square tests were used to compare frequencies of qualitative variables. The level of significance was set at P ≤ .05. Overall intraobserver and interobserver agreements were very good and good, respectively. CBCT analysis found more lesions and lesions of bigger dimension (P < .001). CBCT imaging was also superior in locating lesions in the apical part on the side compared with DOR and in the diagnosis of cortical bone destruction compared with both methods (P < .001). Through CBCT analysis, more root canals and more canals associated with lesions were found. The most informative and reproducible periapical and endodontic status parameters were selected, and a new PESS was proposed. The classification proposed in the present study seems to be reproducible and objective and adds helpful information with respect to the existing indexes. Future studies need to be conducted to validate PESS. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  12. Morel-Lavallee lesion.

    Science.gov (United States)

    Li, Hui; Zhang, Fangjie; Lei, Guanghua

    2014-01-01

    To review current knowledge of the Morel-Lavallee lesion (MLL) to help clinicians become familiar with this entity. Familiarization may decrease missed diagnoses and misdiagnoses. It could also help steer the clinician to the proper treatment choice. A search was performed via PubMed and EMBASE from 1966 to July 2013 using the following keywords: Morel-Lavallee lesion, closed degloving injury, concealed degloving injury, Morel-Lavallee effusion, Morel-Lavallee hematoma, posttraumatic pseudocyst, posttraumatic soft tissue cyst. Chinese and English language literatures relevant to the subject were collected. Their references were also reviewed. Morel-Lavallee lesion is a relatively rare condition involving a closed degloving injury. It is characterized by a filled cystic cavity created by separation of the subcutaneous tissue from the underlying fascia. Apart from the classic location over the region of the greater trochanter, MLLs have been described in other parts of the body. The natural history of MLL has not yet been established. The lesion may decrease in volume, remain stable, enlarge progressively or show a recurrent pattern. Diagnosis of MLL was often missed or delayed. Ultrasonography, computed tomography, and magnetic resonance imaging have great value in the diagnosis of MLL. Treatment of MLL has included compression, local aspiration, open debridement, and sclerodesis. No standard treatment has been established. A diagnosis of MLL should be suspected when a soft, fluctuant area of skin or chronic recurrent fluid collection is found in a region exposed to a previous shear injury. Clinicians and radiologists should be aware of both the acute and chronic appearances to make the correct diagnosis. Treatment decisions should base on association with fractures, the condition of the lesion, symptom and desire of the patient.

  13. Automated detection of Lupus white matter lesions in MRI

    Directory of Open Access Journals (Sweden)

    Eloy Roura Perez

    2016-08-01

    Full Text Available Brain magnetic resonance imaging provides detailed information which can be used to detect and segment white matter lesions (WML. In this work we propose an approach to automatically segment WML in Lupus patients by using T1w and fluid-attenuated inversion recovery (FLAIR images. Lupus WML appear as small focal abnormal tissue observed as hyperintensities in the FLAIR images. The quantification of these WML is a key factor for the stratification of lupus patients and therefore both lesion detection and segmentation play an important role. In our approach, the T1w image is first used to classify the three main tissues of the brain, white matter (WM, gray matter (GM and cerebrospinal fluid (CSF, while the FLAIR image is then used to detect focal WML as outliers of its GM intensity distribution. A set of post-processing steps based on lesion size, tissue neighborhood, and location are used to refine the lesion candidates. The proposal is evaluated on 20 patients, presenting qualitative and quantitative results in terms of precision and sensitivity of lesion detection (True Positive Rate (62% and Positive Prediction Value (80% respectively as well as segmentation accuracy (Dice Similarity Coefficient (72%. Obtained results illustrate the validity of the approach to automatically detect and segment lupus lesions. Besides, our approach is publicly available as a SPM8/12 toolbox extension with a simple parameter configuration.

  14. Research on the Collinear Equation Model of Visual Positioning Based on Visible Light Communication

    Directory of Open Access Journals (Sweden)

    Wang Yuqi

    2015-01-01

    Full Text Available A positioning method based on visible light communication is proposed, which receiving visible light information by low-resolution photodiode array and receiving visual information by the front camera of mobile phone. The terminal position is determined by matching spot information provided by photodiode array with visual information and position information provided by visible light communication. A collinear equation model is derived which based on mobile phone front camera. A hardware-in-loop simulation has been conducted to verify the collinear equation. The three-dimensional positioning error is on the level of decimeter. Moreover, the main factors which affect the positioning accuracy are analyzed in order to further improve the positioning accuracy.

  15. Detection of Fundus Lesions Using Classifier Selection

    Science.gov (United States)

    Nagayoshi, Hiroto; Hiramatsu, Yoshitaka; Sako, Hiroshi; Himaga, Mitsutoshi; Kato, Satoshi

    A system for detecting fundus lesions caused by diabetic retinopathy from fundus images is being developed. The system can screen the images in advance in order to reduce the inspection workload on doctors. One of the difficulties that must be addressed in completing this system is how to remove false positives (which tend to arise near blood vessels) without decreasing the detection rate of lesions in other areas. To overcome this difficulty, we developed classifier selection according to the position of a candidate lesion, and we introduced new features that can distinguish true lesions from false positives. A system incorporating classifier selection and these new features was tested in experiments using 55 fundus images with some lesions and 223 images without lesions. The results of the experiments confirm the effectiveness of the proposed system, namely, degrees of sensitivity and specificity of 98% and 81%, respectively.

  16. Adaptive Indoor Positioning Model Based on WLAN-Fingerprinting for Dynamic and Multi-Floor Environments

    Directory of Open Access Journals (Sweden)

    Iyad Husni Alshami

    2017-08-01

    Full Text Available The Global Positioning System demonstrates the significance of Location Based Services but it cannot be used indoors due to the lack of line of sight between satellites and receivers. Indoor Positioning Systems are needed to provide indoor Location Based Services. Wireless LAN fingerprints are one of the best choices for Indoor Positioning Systems because of their low cost, and high accuracy, however they have many drawbacks: creating radio maps is time consuming, the radio maps will become outdated with any environmental change, different mobile devices read the received signal strength (RSS differently, and peoples’ presence in LOS between access points and mobile device affects the RSS. This research proposes a new Adaptive Indoor Positioning System model (called DIPS based on: a dynamic radio map generator, RSS certainty technique and peoples’ presence effect integration for dynamic and multi-floor environments. Dynamic in our context refers to the effects of people and device heterogeneity. DIPS can achieve 98% and 92% positioning accuracy for floor and room positioning, and it achieves 1.2 m for point positioning error. RSS certainty enhanced the positioning accuracy for floor and room for different mobile devices by 11% and 9%. Then by considering the peoples’ presence effect, the error is reduced by 0.2 m. In comparison with other works, DIPS achieves better positioning without extra devices.

  17. Multicenter assessment of the reproducibility of volumetric radiofrequency-based intravascular ultrasound measurements in coronary lesions that were consecutively stented

    DEFF Research Database (Denmark)

    Huisman, Jennifer; Egede, Rasmus; Rdzanek, Adam

    2012-01-01

    To assess in a multicenter design the between-center reproducibility of volumetric virtual histology intravascular ultrasound (VH-IVUS) measurements with a semi-automated, computer-assisted contour detection system in coronary lesions that were consecutively stented. To evaluate the reproducibility...... of volumetric VH-IVUS measurements, experienced analysts of 4 European IVUS centers performed independent analyses (in total 8,052 cross-sectional analyses) to obtain volumetric data of 40 coronary segments (length 20.0 ± 0.3 mm) from target lesions prior to percutaneous intervention that were performed...... in the setting of stable (65%) or unstable angina pectoris (35%). Geometric and compositional VH-IVUS measurements were highly correlated for the different comparisons. Overall intraclass correlation for vessel, lumen, plaque volume and plaque burden was 0.99, 0.92, 0.96, and 0.83, respectively; for fibrous...

  18. The Complementary Roles of the School Nurse and School Based Health Centers. Position Statement

    Science.gov (United States)

    Ondeck, Lynnette; Combe, Laurie; Baszler, Rita; Wright, Janet

    2015-01-01

    It is the position of the National Association of School Nurses (NASN) that the unique combination of school nursing services and school-based health centers (SBHCs) facilitate positive health outcomes for students. The registered professional school nurse (hereinafter referred to as school nurse) is responsible for management of the daily health…

  19. SU-F-T-469: A Clinically Observed Discrepancy Between Image-Based and Log- Based MLC Position

    Energy Technology Data Exchange (ETDEWEB)

    Neal, B; Ahmed, M; Siebers, J [University of Virginia Health System, Charlottesville, VA (United States)

    2016-06-15

    Purpose: To present a clinical case which challenges the base assumption of log-file based QA, by showing that the actual position of a MLC leaf can suddenly deviate from its programmed and logged position by >1 mm as observed with real-time imaging. Methods: An EPID-based exit-fluence dosimetry system designed to prevent gross delivery errors was used in cine mode to capture portal images during treatment. Visual monitoring identified an anomalous MLC leaf pair gap not otherwise detected by the automatic position verification. The position of the erred leaf was measured on EPID images and log files were analyzed for the treatment in question, the prior day’s treatment, and for daily MLC test patterns acquired on those treatment days. Additional standard test patterns were used to quantify the leaf position. Results: Whereas the log file reported no difference between planned and recorded positions, image-based measurements showed the leaf to be 1.3±0.1 mm medial from the planned position. This offset was confirmed with the test pattern irradiations. Conclusion: It has been clinically observed that log-file derived leaf positions can differ from their actual positions by >1 mm, and therefore cannot be considered to be the actual leaf positions. This cautions the use of log-based methods for MLC or patient quality assurance without independent confirmation of log integrity. Frequent verification of MLC positions through independent means is a necessary precondition to trusting log file records. Intra-treatment EPID imaging provides a method to capture departures from MLC planned positions. Work was supported in part by Varian Medical Systems.

  20. Gastroprotection studies of Schiff base zinc (II) derivative complex against acute superficial hemorrhagic mucosal lesions in rats.

    Science.gov (United States)

    Golbabapour, Shahram; Gwaram, Nura Suleiman; Hassandarvish, Pouya; Hajrezaie, Maryam; Kamalidehghan, Behnam; Abdulla, Mahmood Ameen; Ali, Hapipah Mohd; Hadi, A Hamid A; Majid, Nazia Abdul

    2013-01-01

    The study was carried out to assess the gastroprotective effect of the zinc (II) complex against ethanol-induced acute hemorrhagic lesions in rats. The animals received their respective pre-treatments dissolved in tween 20 (5% v/v), orally. Ethanol (95% v/v) was orally administrated to induce superficial hemorrhagic mucosal lesions. Omeprazole (5.790×10(-5) M/kg) was used as a reference medicine. The pre-treatment with the zinc (II) complex (2.181×10(-5) and 4.362×10(-5) M/kg) protected the gastric mucosa similar to the reference control. They significantly increased the activity levels of nitric oxide, catalase, superoxide dismutase, glutathione and prostaglandin E2, and decreased the level of malondialdehyde. The histology assessments confirmed the protection through remarkable reduction of mucosal lesions and increased the production of gastric mucosa. Immunohistochemistry and western blot analysis indicated that the complex might induced Hsp70 up-regulation and Bax down-regulation. The complex moderately increased the gastroprotectiveness in fine fettle. The acute toxicity approved the non-toxic characteristic of the complex (<87.241×10(-5) M/kg). The gastroprotective effect of the zinc (II) complex was mainly through its antioxidant activity, enzymatic stimulation of prostaglandins E2, and up-regulation of Hsp70. The gastric wall mucus was also a remarkable protective mechanism.

  1. Epidemiological data and a score-based study of renal, hepatic and cerebral lesions in feline infectious peritonitis

    Directory of Open Access Journals (Sweden)

    Thalita Evani Silva de Oliveira

    2017-10-01

    Full Text Available The study describes the epidemiological and pathological findings observed in a population of cats with feline infectious peritonitis (FIP and estimated the degree of tissue destruction in the kidney, brain, and liver. A retrospective study was performed to determine the number of cats with a histopathological diagnosis of FIP between 2005-2016, at the Laboratory of Animal Pathology, Universidade Estadual de Londrina. The histopathological alterations in selected organs (brain, liver and kidneys associated with FIP were described and then compared with a scoring system to estimate the degree of tissue destruction. FIP was diagnosed in 3.7% (19/520 of all cats necropsied during the 11-year period; sexual and breed predominance were not identified. Cats that were less than one-year-old were more frequently diagnosed with FIP. Pyogranulomatous nephritis with vasculitis (94.7%; 18/19, coagulative renal necrosis (84.2%; 16/19, hepatocellular necrosis (57.9; 11/19, and necrotizing leptomeningitis (47.4%; 9/19 were the most frequent lesions observed. Moreover, FIP-associated renal lesions were more severe and frequently observed when compared with those in the brain and liver. It is proposed that necrosis be considered as an important lesion associated with FIP that should be included in the histopathological diagnosis of this disease.

  2. Impact of brain tumour location on emotion and personality: a voxel-based lesion-symptom mapping study on mentalization processes.

    Science.gov (United States)

    Campanella, Fabio; Shallice, Tim; Ius, Tamara; Fabbro, Franco; Skrap, Miran

    2014-09-01

    Patients affected by brain tumours may show behavioural and emotional regulation deficits, sometimes showing flattened affect and sometimes experiencing a true 'change' in personality. However, little evidence is available to the surgeon as to what changes are likely to occur with damage at specific sites, as previous studies have either relied on single cases or provided only limited anatomical specificity, mostly reporting associations rather than dissociations of symptoms. We investigated these aspects in patients undergoing surgery for the removal of cerebral tumours. We argued that many of the problems described can be ascribed to the onset of difficulties in one or more of the different levels of the process of mentalizing (i.e. abstracting and reflecting upon) emotion and intentions, which impacts on everyday behaviour. These were investigated in terms of (i) emotion recognition; (ii) Theory of Mind; (iii) alexithymia; and (iv) self-maturity (personality disorder). We hypothesized that temporo/limbic areas would be critical for processing emotion and intentions at a more perceptual level, while frontal lobe structures would be more critical when higher levels of mentalization/abstraction are required. We administered four different tasks, Task 1: emotion recognition of Ekman faces; Task 2: the Eyes Test (Theory of Mind); Task 3: Toronto Alexithymia Scale; and Task 4: Temperament and Character Inventory (a personality inventory), both immediately before and few days after the operation for the removal of brain tumours in a series of 71 patients (age range: 18-75 years; 33 female) with lesions located in the left or right frontal, temporal and parietal lobes. Lobe-based and voxel-based analysis confirmed that tasks requiring interpretation of emotions and intentions at more basic (less mentalized) levels (Tasks 1 and 2) were more affected by temporo/insular lesions, with emotion recognition (Task 1) being maximally impaired by anterior temporal and amygdala

  3. 78 FR 65006 - National Space-Based Positioning, Navigation, and Timing (PNT) Advisory Board; Meeting

    Science.gov (United States)

    2013-10-30

    ..., Public Law 92-463, as amended, and the President's 2004 U.S. Space-Based Positioning, Navigation, and.... ADDRESSES: The Omni Shoreham Hotel, 2500 Calvert Street NW., Washington, DC 20008. FOR FURTHER INFORMATION...

  4. 78 FR 23598 - National Space-Based Positioning, Navigation, and Timing (PNT) Advisory Board; Meeting

    Science.gov (United States)

    2013-04-19

    ..., Public Law 92-463, as amended, and the President's 2004 U.S. Space-Based Positioning, Navigation, and...: The Melrose Hotel, 2430 Pennsylvania Ave NW., Washington, DC 20037. FOR FURTHER INFORMATION CONTACT...

  5. Incidental benign parotid lesions on FDG-PET: prevalence and clinico-pathologic findings

    International Nuclear Information System (INIS)

    Lim, Il Han; Lee, Won Woo; Chung, Jin Haeng; Park, So Yeon; Kim, Sang Hee; Kim, Yu Kyeong; Kim, Sang Eun

    2007-01-01

    Incidental parotid lesions on F-18 FDG-PET can mimic distant metastasis of underlying malignancy. The prevalence and the clinico-pathologic findings of PET positive parotid lesions have not been known. We investigated how often incidental parotid lesions are found on clinical FDG-PET studies and what the clinico-pathologic characteristics of those parotid lesions are in the present study. We retrospectively reviewed 3,344 cases of FDG-PET which had been obtained in our hospital from May 2003 to Dec 2006. The indications of FDG-PET were: evaluation of known/suspected cancer (n = 3,212) or screening of cancer in healthy subjects (n = 132). Incidental parotid lesion on FDG-PET was defined as an un-expected FDG uptake in one of parotid glands which was not primary target lesion of current FDG/PET. FDG uptake was represented by maximum standardized uptake value (maxSUV). Final diagnosis was made by pathologic analysis or clinical follow-up assessment. Fifteen (0.45% = 15/3,344) incidental parotid lesions were found and they were all benign lesions. The maxSUV ranged from 1.7 to 8.6 (mean ± s.d. = 3.7 ± 1.9). Final diagnoses of the incidental parotid lesions were; Warthin's tumor (n = 2), pleomorphic adenoma (n = 1), other un-specified benign lesion (n 1), and benign lesions under bases of imaging studies (n = 3) and of clinical follow-up (n = 8). All of incidentally found parotid lesions in clinical FDG-PET studies were confirmed as benign lesions with prevalence of 0.45%. Close follow up using PET or CT might be a reasonable approach for determining the nature of incidentally found parotid lesions

  6. An RFID Indoor Positioning Algorithm Based on Bayesian Probability and K-Nearest Neighbor.

    Science.gov (United States)

    Xu, He; Ding, Ye; Li, Peng; Wang, Ruchuan; Li, Yizhu

    2017-08-05

    The Global Positioning System (GPS) is widely used in outdoor environmental positioning. However, GPS cannot support indoor positioning because there is no signal for positioning in an indoor environment. Nowadays, there are many situations which require indoor positioning, such as searching for a book in a library, looking for luggage in an airport, emergence navigation for fire alarms, robot location, etc. Many technologies, such as ultrasonic, sensors, Bluetooth, WiFi, magnetic field, Radio Frequency Identification (RFID), etc., are used to perform indoor positioning. Compared with other technologies, RFID used in indoor positioning is more cost and energy efficient. The Traditional RFID indoor positioning algorithm LANDMARC utilizes a Received Signal Strength (RSS) indicator to track objects. However, the RSS value is easily affected by environmental noise and other interference. In this paper, our purpose is to reduce the location fluctuation and error caused by multipath and environmental interference in LANDMARC. We propose a novel indoor positioning algorithm based on Bayesian probability and K -Nearest Neighbor (BKNN). The experimental results show that the Gaussian filter can filter some abnormal RSS values. The proposed BKNN algorithm has the smallest location error compared with the Gaussian-based algorithm, LANDMARC and an improved KNN algorithm. The average error in location estimation is about 15 cm using our method.

  7. An RFID Indoor Positioning Algorithm Based on Bayesian Probability and K-Nearest Neighbor

    Directory of Open Access Journals (Sweden)

    He Xu

    2017-08-01

    Full Text Available The Global Positioning System (GPS is widely used in outdoor environmental positioning. However, GPS cannot support indoor positioning because there is no signal for positioning in an indoor environment. Nowadays, there are many situations which require indoor positioning, such as searching for a book in a library, looking for luggage in an airport, emergence navigation for fire alarms, robot location, etc. Many technologies, such as ultrasonic, sensors, Bluetooth, WiFi, magnetic field, Radio Frequency Identification (RFID, etc., are used to perform indoor positioning. Compared with other technologies, RFID used in indoor positioning is more cost and energy efficient. The Traditional RFID indoor positioning algorithm LANDMARC utilizes a Received Signal Strength (RSS indicator to track objects. However, the RSS value is easily affected by environmental noise and other interference. In this paper, our purpose is to reduce the location fluctuation and error caused by multipath and environmental interference in LANDMARC. We propose a novel indoor positioning algorithm based on Bayesian probability and K-Nearest Neighbor (BKNN. The experimental results show that the Gaussian filter can filter some abnormal RSS values. The proposed BKNN algorithm has the smallest location error compared with the Gaussian-based algorithm, LANDMARC and an improved KNN algorithm. The average error in location estimation is about 15 cm using our method.

  8. Supporting Seamful Development of Positioning Applications through Model Based Translucent Middleware

    DEFF Research Database (Denmark)

    Jensen, Jakob Langdal

    middleware, and how that middleware can provide developers with methods for controlling application qualities that are related to the positioning process. One key challenge is to understand how to support application development in a heterogeneous domain like that of positioning. Recent trends in application...... middleware used to support application development. We transfer the concept of tactics from the field of software architecture and apply it to specific qualities related to position based applications. We further argue that many of these tactics can be implemented as policies that can be enforced......Positioning technologies are becoming ever more pervasive, and they are used for a growing number of applications in a broad range of fields. We aim to support software developers who create position based applications. More specifically, how support can be provided through the use of specialized...

  9. Stereo-vision-based cooperative-vehicle positioning using OCC and neural networks

    Science.gov (United States)

    Ifthekhar, Md. Shareef; Saha, Nirzhar; Jang, Yeong Min

    2015-10-01

    Vehicle positioning has been subjected to extensive research regarding driving safety measures and assistance as well as autonomous navigation. The most common positioning technique used in automotive positioning is the global positioning system (GPS). However, GPS is not reliably accurate because of signal blockage caused by high-rise buildings. In addition, GPS is error prone when a vehicle is inside a tunnel. Moreover, GPS and other radio-frequency-based approaches cannot provide orientation information or the position of neighboring vehicles. In this study, we propose a cooperative-vehicle positioning (CVP) technique by using the newly developed optical camera communications (OCC). The OCC technique utilizes image sensors and cameras to receive and decode light-modulated information from light-emitting diodes (LEDs). A vehicle equipped with an OCC transceiver can receive positioning and other information such as speed, lane change, driver's condition, etc., through optical wireless links of neighboring vehicles. Thus, the target vehicle position that is too far away to establish an OCC link can be determined by a computer-vision-based technique combined with the cooperation of neighboring vehicles. In addition, we have devised a back-propagation (BP) neural-network learning method for positioning and range estimation for CVP. The proposed neural-network-based technique can estimate target vehicle position from only two image points of target vehicles using stereo vision. For this, we use rear LEDs on target vehicles as image points. We show from simulation results that our neural-network-based method achieves better accuracy than that of the computer-vision method.

  10. Comparison of megavoltage position verification for prostate irradiation based on bony anatomy and implanted fiducials

    International Nuclear Information System (INIS)

    Nederveen, Aart J.; Dehnad, Homan; Heide, Uulke A. van der; Moorselaar, R. Jeroen A. van; Hofman, Pieter; Lagendijk, Jan J.W.

    2003-01-01

    Purpose: The patient position during radiotherapy treatment of prostate cancer can be verified with the help of portal images acquired during treatment. In this study we quantify the clinical consequences of the use of image-based verification based on the bony anatomy and the prostate target itself. Patients and methods: We analysed 2025 portal images and 23 computed tomography (CT) scans from 23 patients with prostate cancer. In all patients gold markers were implanted prior to CT scanning. Statistical data for both random and systematic errors were calculated for displacements of bones and markers and we investigated the effectiveness of an off-line correction protocol. Results: Standard deviations for systematic marker displacement are 2.4 mm in the lateral (LR) direction, 4.4 mm in the anterior-posterior (AP) direction and 3.7 mm in the caudal-cranial direction (CC). Application of off-line position verification based on the marker positions results in a shrinkage of the systematic error to well below 1 mm. Position verification based on the bony anatomy reduces the systematic target uncertainty to 50% in the AP direction and in the LR direction. No reduction was observed in the CC direction. For six out of 23 patients we found an increase of the systematic error after application of bony anatomy-based position verification. Conclusions: We show that even if correction based on the bony anatomy is applied, considerable margins have to be set to account for organ motion. Our study highlights that for individual patients the systematic error can increase after application of bony anatomy-based position verification, whereas the population standard deviation will decrease. Off-line target-based position verification effectively reduces the systematic error to well below 1 mm, thus enabling significant margin reduction

  11. HER-2, ER, PR status concordance in primary breast cancer and corresponding metastatic lesion in lymph node in Chinese women.

    Science.gov (United States)

    Li, Min Hua; Hou, Chuan Ling; Wang, Cheng; Sun, Ai Jing

    2016-04-01

    To compare the expression of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER-2) in the primary site and the metastatic lesion of lymph nodes in invasive breast cancer for investigating whether the expression of these biomarkers in the primary site could act as a surrogate to the lymphatic metastatic lesion in the same patient. In lymphatic metastatic lesion and corresponding primary lesion of 107 cases of invasive breast cancer, ER and PR statuses were assessed by immunohistochemistry (IHC). HER-2 expression level was evaluated by IHC and/or fluorescence in situ hybridization (FISH). In the primary lesions, 43.9% were ER positive; 46.7% were PR positive; 34.6% were HER-2 positive. In corresponding lymphatic metastatic lesions, the HER-2 status was concordant in 90 patients; 9 patients were diagnosed positive in metastatic lesion while negative in primary lesion; 8 patients were negative in metastatic lesion while positive in primary site (agreement, 84.1%; κ=0.647). A change in ER status was observed in 24 cases: 17 cases positive in metastatic site while negative in primary site; 7 cases negative in metastatic site while positive in primary site (agreement, 77.6%; κ=0.534). PR status discordance between the primary lesion and the metastatic regional lymph nodes was reported in 19 cases (agreement, 82.2%; κ=0.640). This study revealed that there was only a moderate concordance of ER, PR and HER-2 status between primary tumors and metastatic lymph nodes. These results indicate that it was inappropriate to predict the status of ER, PR and HER-2 in metastatic lymph nodes based on the results of evaluation of that in primary lesions. Copyright © 2015 Elsevier GmbH. All rights reserved.

  12. Development of an online, publicly accessible naive Bayesian decision support tool for mammographic mass lesions based on the American College of Radiology (ACR) BI-RADS lexicon

    Energy Technology Data Exchange (ETDEWEB)

    Benndorf, Matthias; Kotter, Elmar; Langer, Mathias [University Hospital Freiburg, Department of Radiology, Freiburg (Germany); Herda, Christoph [Kantonsspital Graubuenden, Chur (Switzerland); Wu, Yirong; Burnside, Elizabeth S. [University of Wisconsin-Madison School of Medicine and Public Health, Department of Radiology, Madison, WI (United States)

    2015-06-01

    To develop and validate a decision support tool for mammographic mass lesions based on a standardized descriptor terminology (BI-RADS lexicon) to reduce variability of practice. We used separate training data (1,276 lesions, 138 malignant) and validation data (1,177 lesions, 175 malignant). We created naive Bayes (NB) classifiers from the training data with tenfold cross-validation. Our ''inclusive model'' comprised BI-RADS categories, BI-RADS descriptors, and age as predictive variables; our ''descriptor model'' comprised BI-RADS descriptors and age. The resulting NB classifiers were applied to the validation data. We evaluated and compared classifier performance with ROC-analysis. In the training data, the inclusive model yields an AUC of 0.959; the descriptor model yields an AUC of 0.910 (P < 0.001). The inclusive model is superior to the clinical performance (BI-RADS categories alone, P < 0.001); the descriptor model performs similarly. When applied to the validation data, the inclusive model yields an AUC of 0.935; the descriptor model yields an AUC of 0.876 (P < 0.001). Again, the inclusive model is superior to the clinical performance (P < 0.001); the descriptor model performs similarly. We consider our classifier a step towards a more uniform interpretation of combinations of BI-RADS descriptors. We provide our classifier at www.ebm-radiology.com/nbmm/index.html. (orig.)

  13. Development of an online, publicly accessible naive Bayesian decision support tool for mammographic mass lesions based on the American College of Radiology (ACR) BI-RADS lexicon

    International Nuclear Information System (INIS)

    Benndorf, Matthias; Kotter, Elmar; Langer, Mathias; Herda, Christoph; Wu, Yirong; Burnside, Elizabeth S.

    2015-01-01

    To develop and validate a decision support tool for mammographic mass lesions based on a standardized descriptor terminology (BI-RADS lexicon) to reduce variability of practice. We used separate training data (1,276 lesions, 138 malignant) and validation data (1,177 lesions, 175 malignant). We created naive Bayes (NB) classifiers from the training data with tenfold cross-validation. Our ''inclusive model'' comprised BI-RADS categories, BI-RADS descriptors, and age as predictive variables; our ''descriptor model'' comprised BI-RADS descriptors and age. The resulting NB classifiers were applied to the validation data. We evaluated and compared classifier performance with ROC-analysis. In the training data, the inclusive model yields an AUC of 0.959; the descriptor model yields an AUC of 0.910 (P < 0.001). The inclusive model is superior to the clinical performance (BI-RADS categories alone, P < 0.001); the descriptor model performs similarly. When applied to the validation data, the inclusive model yields an AUC of 0.935; the descriptor model yields an AUC of 0.876 (P < 0.001). Again, the inclusive model is superior to the clinical performance (P < 0.001); the descriptor model performs similarly. We consider our classifier a step towards a more uniform interpretation of combinations of BI-RADS descriptors. We provide our classifier at www.ebm-radiology.com/nbmm/index.html. (orig.)

  14. Perfusion maps of the whole liver based on high temporal and spatial resolution contrast-enhanced MRI (4D THRIVE): Feasibility and initial results in focal liver lesions

    International Nuclear Information System (INIS)

    Coenegrachts, Kenneth; Ghekiere, Johan; Denolin, Vincent; Gabriele, Beck; Herigault, Gwen; Haspeslagh, Marc; Daled, Peter; Bipat, Shandra; Stoker, Jaap; Rigauts, Hans

    2010-01-01

    Purpose: To prospectively evaluate a new imaging sequence (4D THRIVE) for whole liver perfusion in high temporal and spatial resolution. Feasibility of parametric mapping and its potential for characterizing focal liver lesions (FLLs) are investigated. Materials and methods: Fifteen patients suspected for colorectal liver metastases (LMs) were included. Parametric maps were evaluated qualitatively (ring-enhancement and lesion heterogeneity) and compared to three-phased contrast-enhanced MRI. Quantitative analysis was based on average perfusion values of entire FLLs. Reference standard comprised surgery with histopathology or follow-up imaging. Fisher's exact test was used for qualitative and Kruskal-Wallis test for quantitative analysis. Results: In total 29 LMs, 17 hemangiomas and 4 focal nodular hyperplasias were evaluated. FLLs could be differentiated by qualitative assessment of parametric maps respectively three-phased contrast-enhanced MRI (Fisher's p < 0.001 for comparisons between LMs and hemangiomas and LMs and FNHs for both ring-enhancement and lesion heterogeneity) rather than by quantitative analysis of parametric maps (Chi-square for Kep = 0.33 (p = 0.847) and Chi-square for Kel = 1.35 (p = 0.509)). Conclusion: This preliminary study shows potential of 4D THRIVE for whole liver imaging enabling calculation of parametric maps. Qualitative rather than quantitative analysis was accurate for differentiating malignant and benign FLLs.

  15. Experimental approbation of a new ultrosound contrast agent based on sulfur geksafluoride in diagnostics of focal liver lesions of inflammatory genesis

    Directory of Open Access Journals (Sweden)

    S. V. Fomina

    2017-01-01

    Full Text Available Purpose of the study. Experimental approbation of a new domestic ultrasound contrast agent (UCA based on sulfur hexafluoride in the diagnosis of focal liver lesions of inflammatory genesis.Materials and methods. The investigated ultrasound contrast agent (UCA was a heterogeneous gas-liquid system consisting of micro bubbles of a sparingly soluble gas of sulfur hexafluoride (SF6 surrounded by a flexible mobile membrane of surfactants. Experimental work was carried out on rabbits. The study group included rabbits of males and females with focal liver lesion of inflammatory genesis (n = 12 weighing 1500- 1700 g. UCA was administered to animals in the ear vein. Focal lesions of the liver in animals were created in the experimental laboratory conditions. 14 days after the operation, all animals were subjected to ultrasound examination of the surgical intervention zones by using the Toshiba Aplio 400 scanners (Japan with a 3,5–8 MHz convection sensor. In a natural study, the size, structure and echogenicity of the focus were assessed, the degree of vascularization, the evenness and clarity of the contours were determined. When performing post contrast ultrasound, the time of the onset of contrast enhancement, the total duration of contrast, the changes in the contrast enhancement of the focus in different phases of the study were measured, the dimensions of the focus were measured, and the evenness and acuity of contours were measured. For histological examination, liver fragments and lungs were used. 

  16. Kawasaki disease-associated coronary artery lesions with navigator echo-based. Respiratory-gated three dimensional coronary magnetic resonance angiography compared with echocardiography in young children

    International Nuclear Information System (INIS)

    Amino, Masayuki; Teraoka, Kunihiko; Hirano, Masaharu; Kawashima, Naoshi; Kakizaki, Dai; Ookubo, Yasuo; Sasaki, Kazuyoshi; Katuyama, Hiroaki

    2004-01-01

    Navigator echo-based respiratory-gated three dimensional coronary magnetic resonance angiography (3D-CMRA) was compared with echocardiography, to determine whether 3D-CMRA was useful for the evaluation of Kawasaki disease-associated coronary artery lesions. Sixteen consecutive patients (imaging was performed 17 times in total) who were given a diagnosis of Kawasaki's disease at the pediatric department of our hospital and examined for the precise examination of complicating coronary artery lesions on MRI using a navigator-echo technique because of their incapability of holding their breath during imaging were entered into the present study. A 1.5T MRI system was used. Gd-DOTA was given at a total volume of 0.1 mmol/kg. During imaging, CMRA visualized the left coronary arteries in all 17 cases and the right coronary arteries in 16 cases, but not in one case. The left main coronary trunk segment no.5 was demonstrated in all cases with CMRA, but not in 4 cases with echocardiography. The left anterior descending branch no.6 was visualized in 11 of the 17 cases with CMRA, but only in 5 cases with echocardiography. The left circumflex branch no.11 was observed in 6 cases with CMRA, but only in 2 cases with echocardiography. As for the right coronary arteries, branches no.1 and no.2 were observed in 16 and 9 cases with CMRA, respectively, and in 13 and 3 cases with echocardiography, respectively. Vascular diameters measured on CMRA were almost identical to those on echocardiography, within the range of arteries visualized. 3D-CMRA combined with a navigator echo technique appears to be a useful tool for the observation of coronary artery lesions associated with Kawasaki's disease because it is superior in lesion visualization to echocardiography. (author)

  17. Quantitative Assessment of Degenerative Cartilage and Subchondral Bony Lesions in a Preserved Cadaveric Knee: Propagation-Based Phase-Contrast CT Versus Conventional MRI and CT.

    Science.gov (United States)

    Geith, Tobias; Brun, Emmanuel; Mittone, Alberto; Gasilov, Sergei; Weber, Loriane; Adam-Neumair, Silvia; Bravin, Alberto; Reiser, Maximilian; Coan, Paola; Horng, Annie

    2018-04-09

    The aim of this study was to quantitatively assess hyaline cartilage and subchondral bone conditions in a fully preserved cadaveric human knee joint using high-resolution x-ray propagation-based phase-contrast imaging (PBI) CT and to compare the performance of the new technique with conventional CT and MRI. A cadaveric human knee was examined using an x-ray beam of 60 keV, a detector with a 90-mm 2 FOV, and a pixel size of 46 × 46 μm 2 . PBI CT images were reconstructed with both the filtered back projection algorithm and the equally sloped tomography method. Conventional 3-T MRI and CT were also performed. Measurements of cartilage thickness, cartilage lesions, International Cartilage Repair Society scoring, and detection of subchondral bone changes were evaluated. Visual inspection of the specimen akin to arthroscopy was conducted and served as a standard of reference for lesion detection. Loss of cartilage height was visible on PBI CT and MRI. Quantification of cartilage thickness showed a strong correlation between the two modalities. Cartilage lesions appeared darker than the adjacent cartilage on PBI CT. PBI CT showed similar agreement to MRI for depicting cartilage substance defects or lesions compared with the visual inspection. The assessment of subchondral bone cysts showed moderate to strong agreement between PBI CT and CT. In contrast to the standard clinical methods of MRI and CT, PBI CT is able to simultaneously depict cartilage and bony changes at high resolution. Though still an experimental technique, PBI CT is a promising high-resolution imaging method to evaluate comprehensive changes of osteoarthritic disease in a clinical setting.

  18. Predictors of positive health in disability pensioners: a population-based questionnaire study using Positive Odds Ratio

    Directory of Open Access Journals (Sweden)

    Edén Lena

    2002-09-01

    Full Text Available Abstract Background Determinants of ill-health have been studied far more than determinants of good and improving health. Health promotion measures are important even among individuals with chronic diseases. The aim of this study was to find predictors of positive subjective health among disability pensioners (DPs with musculoskeletal disorders. Methods Two questionnaire surveys were performed among 352 DPs with musculoskeletal disorders. Two groups were defined: DPs with positive health and negative health, respectively. In consequence with the health perspective in this study the conception Positive Odds Ratio was defined and used in the logistic regression analyses instead of the commonly used odds ratio. Results Positive health was associated with age ≥ 55 years, not being an immigrant, not having fibromyalgia as the main diagnosis for granting an early retirement, no regular use of analgesics, a high ADL capacity, a positive subjective health preceding the study period, and good quality of life. Conclusion Positive odds ratio is a concept well adapted to theories of health promotion. It can be used in relation to positive outcomes instead of risks. Suggested health promotion and secondary prevention efforts among individuals with musculoskeletal disorders are 1 to avoid a disability pension for individuals

  19. Compensation of position errors in passivity based teleoperation over packet switched communication networks

    NARCIS (Netherlands)

    Secchi, C; Stramigioli, Stefano; Fantuzzi, C.

    Because of the use of scattering based communication channels, passivity based telemanipulation systems can be subject to a steady state position error between master and slave robots. In this paper, we consider the case in which the passive master and slave sides communicate through a packet

  20. Persuasion Model and Its Evaluation Based on Positive Change Degree of Agent Emotion

    Science.gov (United States)

    Jinghua, Wu; Wenguang, Lu; Hailiang, Meng

    For it can meet needs of negotiation among organizations take place in different time and place, and for it can make its course more rationality and result more ideal, persuasion based on agent can improve cooperation among organizations well. Integrated emotion change in agent persuasion can further bring agent advantage of artificial intelligence into play. Emotion of agent persuasion is classified, and the concept of positive change degree is given. Based on this, persuasion model based on positive change degree of agent emotion is constructed, which is explained clearly through an example. Finally, the method of relative evaluation is given, which is also verified through a calculation example.

  1. Surgical neuro navigator guided by preoperative magnetic resonance images, based on a magnetic position sensor

    International Nuclear Information System (INIS)

    Perini, Ana Paula; Siqueira, Rogerio Bulha; Carneiro, Antonio Adilton Oliveira; Oliveira, Lucas Ferrari de; Machado, Helio Rubens

    2009-01-01

    Image guided neurosurgery enables the neurosurgeon to navigate inside the patient's brain using pre-operative images as a guide and a tracking system, during a surgery. Following a calibration procedure, three-dimensional position and orientation of surgical instruments may be transmitted to computer. The spatial information is used to access a region of interest, in the pre-operative images, displaying them to the neurosurgeon during the surgical procedure. However, when a craniotomy is involved and the lesion is removed, movements of brain tissue can be a significant source of error in these conventional navigation systems. The architecture implemented in this work intends the development of a system to surgical planning and orientation guided by ultrasound image. For surgical orientation, the software developed allows the extraction of slices from the volume of the magnetic resonance images (MRI) with orientation supplied by a magnetic position sensor (Polhemus R ). The slices extracted with this software are important because they show the cerebral area that the neurosurgeon is observing during the surgery, and besides they can be correlated with the intra-operative ultrasound images to detect and to correct the deformation of brain tissue during the surgery. Also, a tool for per-operative navigation was developed, providing three orthogonal planes through the image volume. In the methodology used for the software implementation, the Python tm programming language and the Visualization Toolkit (VTK) graphics library were used. The program to extract slices of the MRI volume allowed the application of transformations in the volume, using coordinates supplied by the position sensor. (author)

  2. An Adaptive Connectivity-based Centroid Algorithm for Node Positioning in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Aries Pratiarso

    2015-06-01

    Full Text Available In wireless sensor network applications, the position of nodes is randomly distributed following the contour of the observation area. A simple solution without any measurement tools is provided by range-free method. However, this method yields the coarse estimating position of the nodes. In this paper, we propose Adaptive Connectivity-based (ACC algorithm. This algorithm is a combination of Centroid as range-free based algorithm, and hop-based connectivity algorithm. Nodes have a possibility to estimate their own position based on the connectivity level between them and their reference nodes. Each node divides its communication range into several regions where each of them has a certain weight depends on the received signal strength. The weighted value is used to obtain the estimated position of nodes. Simulation result shows that the proposed algorithm has up to 3 meter error of estimated position on 100x100 square meter observation area, and up to 3 hop counts for 80 meters' communication range. The proposed algorithm performs an average error positioning up to 10 meters better than Weighted Centroid algorithm. Keywords: adaptive, connectivity, centroid, range-free.

  3. Relative Panoramic Camera Position Estimation for Image-Based Virtual Reality Networks in Indoor Environments

    Science.gov (United States)

    Nakagawa, M.; Akano, K.; Kobayashi, T.; Sekiguchi, Y.

    2017-09-01

    Image-based virtual reality (VR) is a virtual space generated with panoramic images projected onto a primitive model. In imagebased VR, realistic VR scenes can be generated with lower rendering cost, and network data can be described as relationships among VR scenes. The camera network data are generated manually or by an automated procedure using camera position and rotation data. When panoramic images are acquired in indoor environments, network data should be generated without Global Navigation Satellite Systems (GNSS) positioning data. Thus, we focused on image-based VR generation using a panoramic camera in indoor environments. We propose a methodology to automate network data generation using panoramic images for an image-based VR space. We verified and evaluated our methodology through five experiments in indoor environments, including a corridor, elevator hall, room, and stairs. We confirmed that our methodology can automatically reconstruct network data using panoramic images for image-based VR in indoor environments without GNSS position data.

  4. A positioning system for forest diseases and pests based on GIS and PTZ camera

    International Nuclear Information System (INIS)

    Wang, Z B; Zhao, F F; Wang, C B; Wang, L L

    2014-01-01

    Forest diseases and pests cause enormous economic losses and ecological damage every year in China. To prevent and control forest diseases and pests, the key is to get accurate information timely. In order to improve monitoring coverage rate and economize on manpower, a cooperative investigation model for forest diseases and pests is put forward. It is composed of video positioning system and manual labor reconnaissance with mobile GIS embedded in PDA. Video system is used to scan the disaster area, and is particularly effective on where trees are withered. Forest diseases prevention and control workers can check disaster area with PDA system. To support this investigation model, we developed a positioning algorithm and a positioning system. The positioning algorithm is based on DEM and PTZ camera. Moreover, the algorithm accuracy is validated. The software consists of 3D GIS subsystem, 2D GIS subsystem, video control subsystem and disaster positioning subsystem. 3D GIS subsystem makes positioning visual, and practically easy to operate. 2D GIS subsystem can output disaster thematic map. Video control subsystem can change Pan/Tilt/Zoom of a digital camera remotely, to focus on the suspected area. Disaster positioning subsystem implements the positioning algorithm. It is proved that the positioning system can observe forest diseases and pests in practical application for forest departments

  5. Reporting of Positive Results in Randomized Controlled Trials of Mindfulness-Based Mental Health Interventions.

    Directory of Open Access Journals (Sweden)

    Stephanie Coronado-Montoya

    Full Text Available A large proportion of mindfulness-based therapy trials report statistically significant results, even in the context of very low statistical power. The objective of the present study was to characterize the reporting of "positive" results in randomized controlled trials of mindfulness-based therapy. We also assessed mindfulness-based therapy trial registrations for indications of possible reporting bias and reviewed recent systematic reviews and meta-analyses to determine whether reporting biases were identified.CINAHL, Cochrane CENTRAL, EMBASE, ISI, MEDLINE, PsycInfo, and SCOPUS databases were searched for randomized controlled trials of mindfulness-based therapy. The number of positive trials was described and compared to the number that might be expected if mindfulness-based therapy were similarly effective compared to individual therapy for depression. Trial registries were searched for mindfulness-based therapy registrations. CINAHL, Cochrane CENTRAL, EMBASE, ISI, MEDLINE, PsycInfo, and SCOPUS were also searched for mindfulness-based therapy systematic reviews and meta-analyses.108 (87% of 124 published trials reported ≥1 positive outcome in the abstract, and 109 (88% concluded that mindfulness-based therapy was effective, 1.6 times greater than the expected number of positive trials based on effect size d = 0.55 (expected number positive trials = 65.7. Of 21 trial registrations, 13 (62% remained unpublished 30 months post-trial completion. No trial registrations adequately specified a single primary outcome measure with time of assessment. None of 36 systematic reviews and meta-analyses concluded that effect estimates were overestimated due to reporting biases.The proportion of mindfulness-based therapy trials with statistically significant results may overstate what would occur in practice.

  6. Secondary syphilis lesions resembling pityriasis

    International Nuclear Information System (INIS)

    Dar, N.R.; Ali, L.; Nawaz, M.A.

    2007-01-01

    This case report describes a male patient who presented with generalized, centrally-ulcerated papules with crusts and hypopigmented macules. Initially, differential diagnostic considerations included pityriasis lichenoides but the serology for syphilis was positive and there was a rapid response to penicillin with clearing of the lesions at the end of three weeks treatment. (author)

  7. Research on correction algorithm of laser positioning system based on four quadrant detector

    Science.gov (United States)

    Gao, Qingsong; Meng, Xiangyong; Qian, Weixian; Cai, Guixia

    2018-02-01

    This paper first introduces the basic principle of the four quadrant detector, and a set of laser positioning experiment system is built based on the four quadrant detector. Four quadrant laser positioning system in the actual application, not only exist interference of background light and detector dark current noise, and the influence of random noise, system stability, spot equivalent error can't be ignored, so it is very important to system calibration and correction. This paper analyzes the various factors of system positioning error, and then propose an algorithm for correcting the system error, the results of simulation and experiment show that the modified algorithm can improve the effect of system error on positioning and improve the positioning accuracy.

  8. NONLINEAR FILTER METHOD OF GPS DYNAMIC POSITIONING BASED ON BANCROFT ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    ZHANGQin; TAOBen-zao; ZHAOChao-ying; WANGLi

    2005-01-01

    Because of the ignored items after linearization, the extended Kalman filter (EKF) becomes a form of suboptimal gradient descent algorithm. The emanative tendency exists in GPS solution when the filter equations are ill-posed. The deviation in the estimation cannot be avoided. Furthermore, the true solution may be lost in pseudorange positioning because the linearized pseudorange equations are partial solutions. To solve the above problems in GPS dynamic positioning by using EKF, a closed-form Kalman filter method called the two-stage algorithm is presented for the nonlinear algebraic solution of GPS dynamic positioning based on the global nonlinear least squares closed algorithm--Bancroft numerical algorithm of American. The method separates the spatial parts from temporal parts during processing the GPS filter problems, and solves the nonlinear GPS dynamic positioning, thus getting stable and reliable dynamic positioning solutions.

  9. Computerized detection of mass lesions in digital mammograms

    International Nuclear Information System (INIS)

    Yin, F.F.; Giger, M.L.; Doi, K.; Metz, C.E.; Vyborny, C.J.; Schmidt, R.A.

    1989-01-01

    Early detection of breast cancer from the periodic screening of asymptomatic women could reduce breast cancer mortality by at least 40%. The authors are developing a computerized scheme for the detection of mass lesions in digital mammograms as an aid to radiologists in such high volume screening programs. Based on left-right architectural symmetry and gray-level histogram analysis, bilateral subtraction of left and right breast images is performed. False-positive detections included in bilateral-difference images are reduced with various images feature-extraction techniques. The database involves clinical film mammograms digitized by a TV camera and analyzed on a Micro-VAX workstation. Among five different bilateral subtraction techniques investigated, a nonlinear approach provided superior lesion enhancement. Feature-extraction techniques reduced substantially the remaining false-positives. Preliminary results, for 32 pairs of clinical mammograms, yielded a true-positive rate of approximately 95% with a false-positive rate of about 2 per image

  10. Mover Position Detection for PMTLM Based on Linear Hall Sensors through EKF Processing.

    Science.gov (United States)

    Yan, Leyang; Zhang, Hui; Ye, Peiqing

    2017-04-06

    Accurate mover position is vital for a permanent magnet tubular linear motor (PMTLM) control system. In this paper, two linear Hall sensors are utilized to detect the mover position. However, Hall sensor signals contain third-order harmonics, creating errors in mover position detection. To filter out the third-order harmonics, a signal processing method based on the extended Kalman filter (EKF) is presented. The limitation of conventional processing method is first analyzed, and then EKF is adopted to detect the mover position. In the EKF model, the amplitude of the fundamental component and the percentage of the harmonic component are taken as state variables, and they can be estimated based solely on the measured sensor signals. Then, the harmonic component can be calculated and eliminated. The proposed method has the advantages of faster convergence, better stability and higher accuracy. Finally, experimental results validate the effectiveness and superiority of the proposed method.

  11. Robust Operation of Tendon-Driven Robot Fingers Using Force and Position-Based Control Laws

    Science.gov (United States)

    Abdallah, Muhammad E (Inventor); Platt, Jr., Robert J. (Inventor); Reiland, Matthew J (Inventor); Hargrave, Brian (Inventor); Diftler, Myron A (Inventor); Strawser, Philip A (Inventor); Ihrke, Chris A. (Inventor)

    2013-01-01

    A robotic system includes a tendon-driven finger and a control system. The system controls the finger via a force-based control law when a tension sensor is available, and via a position-based control law when a sensor is not available. Multiple tendons may each have a corresponding sensor. The system selectively injects a compliance value into the position-based control law when only some sensors are available. A control system includes a host machine and a non-transitory computer-readable medium having a control process, which is executed by the host machine to control the finger via the force- or position-based control law. A method for controlling the finger includes determining the availability of a tension sensor(s), and selectively controlling the finger, using the control system, via the force or position-based control law. The position control law allows the control system to resist disturbances while nominally maintaining the initial state of internal tendon tensions.

  12. Mitigating Errors in External Respiratory Surrogate-Based Models of Tumor Position

    International Nuclear Information System (INIS)

    Malinowski, Kathleen T.; McAvoy, Thomas J.; George, Rohini; Dieterich, Sonja; D'Souza, Warren D.

    2012-01-01

    Purpose: To investigate the effect of tumor site, measurement precision, tumor–surrogate correlation, training data selection, model design, and interpatient and interfraction variations on the accuracy of external marker-based models of tumor position. Methods and Materials: Cyberknife Synchrony system log files comprising synchronously acquired positions of external markers and the tumor from 167 treatment fractions were analyzed. The accuracy of Synchrony, ordinary-least-squares regression, and partial-least-squares regression models for predicting the tumor position from the external markers was evaluated. The quantity and timing of the data used to build the predictive model were varied. The effects of tumor–surrogate correlation and the precision in both the tumor and the external surrogate position measurements were explored by adding noise to the data. Results: The tumor position prediction errors increased during the duration of a fraction. Increasing the training data quantities did not always lead to more accurate models. Adding uncorrelated noise to the external marker-based inputs degraded the tumor–surrogate correlation models by 16% for partial-least-squares and 57% for ordinary-least-squares. External marker and tumor position measurement errors led to tumor position prediction changes 0.3–3.6 times the magnitude of the measurement errors, varying widely with model algorithm. The tumor position prediction errors were significantly associated with the patient index but not with the fraction index or tumor site. Partial-least-squares was as accurate as Synchrony and more accurate than ordinary-least-squares. Conclusions: The accuracy of surrogate-based inferential models of tumor position was affected by all the investigated factors, except for the tumor site and fraction index.

  13. Mitigating Errors in External Respiratory Surrogate-Based Models of Tumor Position

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, Kathleen T. [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States); McAvoy, Thomas J. [Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States); Department of Chemical and Biomolecular Engineering and Institute of Systems Research, University of Maryland, College Park, MD (United States); George, Rohini [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Dieterich, Sonja [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); D' Souza, Warren D., E-mail: wdsou001@umaryland.edu [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States)

    2012-04-01

    Purpose: To investigate the effect of tumor site, measurement precision, tumor-surrogate correlation, training data selection, model design, and interpatient and interfraction variations on the accuracy of external marker-based models of tumor position. Methods and Materials: Cyberknife Synchrony system log files comprising synchronously acquired positions of external markers and the tumor from 167 treatment fractions were analyzed. The accuracy of Synchrony, ordinary-least-squares regression, and partial-least-squares regression models for predicting the tumor position from the external markers was evaluated. The quantity and timing of the data used to build the predictive model were varied. The effects of tumor-surrogate correlation and the precision in both the tumor and the external surrogate position measurements were explored by adding noise to the data. Results: The tumor position prediction errors increased during the duration of a fraction. Increasing the training data quantities did not always lead to more accurate models. Adding uncorrelated noise to the external marker-based inputs degraded the tumor-surrogate correlation models by 16% for partial-least-squares and 57% for ordinary-least-squares. External marker and tumor position measurement errors led to tumor position prediction changes 0.3-3.6 times the magnitude of the measurement errors, varying widely with model algorithm. The tumor position prediction errors were significantly associated with the patient index but not with the fraction index or tumor site. Partial-least-squares was as accurate as Synchrony and more accurate than ordinary-least-squares. Conclusions: The accuracy of surrogate-based inferential models of tumor position was affected by all the investigated factors, except for the tumor site and fraction index.

  14. Red lesion detection using background estimation and lesions characteristics in diabetic retinal image

    Science.gov (United States)

    Zhang, Dongbo; Peng, Yinghui; Yi, Yao; Shang, Xingyu

    2013-10-01

    Detection of red lesions [hemorrhages (HRs) and microaneurysms (MAs)] is crucial for the diagnosis of early diabetic retinopathy. A method based on background estimation and adapted to specific characteristics of HRs and MAs is proposed. Candidate red lesions are located by background estimation and Mahalanobis distance measure and then some adaptive postprocessing techniques, which include vessel detection, nonvessel exclusion based on shape analysis, and noise points exclusion by double-ring filter (only used for MAs detection), are conducted to remove nonlesion pixels. The method is evaluated on our collected image dataset, and experimental results show that it is better than or approximate to other previous approaches. It is effective to reduce the false-positive and false-negative results that arise from incomplete and inaccurate vessel structure.

  15. Methodological Approach to Company Cash Flows Target-Oriented Forecasting Based on Financial Position Analysis

    OpenAIRE

    Sergey Krylov

    2012-01-01

    The article treats a new methodological approach to the company cash flows target-oriented forecasting based on its financial position analysis. The approach is featured to be universal and presumes application of the following techniques developed by the author: financial ratio values correction techniques and correcting cash flows techniques. The financial ratio values correction technique assumes to analyze and forecast company financial position while the correcting cash flows technique i...

  16. A Navigation/Positioning Service Based on Pseudolites Installed on Stratospheric Airships

    OpenAIRE

    辻井, 利昭; TSUJII, Toshiaki; 張替, 正敏; HARIGAE, Masatoshi

    2002-01-01

    Transmitters of GPS-like signals, called pseudolites (PL) or "pseudo-satellites" have been widely investigated as an additional ranging source for performance enhancement of GPS. Ground-based GPS augmentation systems using pseudolites have been investigated for several applications such as vehicle navigation in downtown urban canyons, positioning in deep open-cut pits and mines and precision landing of aircraft. The concept of an innovative GPS navigation/ positioning system augmented by airs...

  17. Columnar cell lesions of the canine mammary gland: pathological features and immunophenotypic analysis

    Directory of Open Access Journals (Sweden)

    Cassali Geovanni D

    2010-02-01

    Full Text Available Abstract Background It has been suggested that columnar cell lesions indicate an alteration of the human mammary gland involved in the development of breast cancer. They have not previously been described in canine mammary gland. The aim of this paper is describe the morphologic spectrum of columnar cell lesions in canine mammary gland specimens and their association with other breast lesions. Methods A total of 126 lesions were subjected to a comprehensive morphological review based upon the human breast classification system for columnar cell lesions. The presence of preinvasive (epithelial hyperplasia and in situ carcinoma and invasive lesions was determined and immunophenotypic analysis (estrogen receptor (ER, progesterone receptor (PgR, high molecular weight cytokeratin (34βE-12, E-cadherin, Ki-67, HER-2 and P53 was perfomed. Results Columnar cell lesions were identified in 67 (53.1% of the 126 canine mammary glands with intraepithelial alterations. They were observed in the terminal duct lobular units and characterized at dilated acini may be lined by several layers of columnar epithelial cells with elongated nuclei. Of the columnar cell lesions identified, 41 (61.2% were without and 26 (38.8% with atypia. Association with ductal hyperplasia was observed in 45/67 (67.1%. Sixty (89.5% of the columnar cell lesions coexisted with neoplastic lesions (20 in situ carcinomas, 19 invasive carcinomas and 21 benign tumors. The columnar cells were ER, PgR and E-cadherin positive but negative for cytokeratin 34βE-12, HER-2 and P53. The proliferation rate as measured by Ki-67 appeared higher in the lesions analyzed than in normal TDLUs. Conclusions Columnar cell lesions in canine mammary gland are pathologically and immunophenotypically similar to those in human breast. This may suggest that dogs are a suitable model for the comparative study of noninvasive breast lesions.

  18. Columnar cell lesions of the canine mammary gland: pathological features and immunophenotypic analysis

    International Nuclear Information System (INIS)

    Ferreira, Enio; Gobbi, Helenice; Saraiva, Bruna S; Cassali, Geovanni D

    2010-01-01

    It has been suggested that columnar cell lesions indicate an alteration of the human mammary gland involved in the development of breast cancer. They have not previously been described in canine mammary gland. The aim of this paper is describe the morphologic spectrum of columnar cell lesions in canine mammary gland specimens and their association with other breast lesions. A total of 126 lesions were subjected to a comprehensive morphological review based upon the human breast classification system for columnar cell lesions. The presence of preinvasive (epithelial hyperplasia and in situ carcinoma) and invasive lesions was determined and immunophenotypic analysis (estrogen receptor (ER), progesterone receptor (PgR), high molecular weight cytokeratin (34βE-12), E-cadherin, Ki-67, HER-2 and P53) was perfomed. Columnar cell lesions were identified in 67 (53.1%) of the 126 canine mammary glands with intraepithelial alterations. They were observed in the terminal duct lobular units and characterized at dilated acini may be lined by several layers of columnar epithelial cells with elongated nuclei. Of the columnar cell lesions identified, 41 (61.2%) were without and 26 (38.8%) with atypia. Association with ductal hyperplasia was observed in 45/67 (67.1%). Sixty (89.5%) of the columnar cell lesions coexisted with neoplastic lesions (20 in situ carcinomas, 19 invasive carcinomas and 21 benign tumors). The columnar cells were ER, PgR and E-cadherin positive but negative for cytokeratin 34βE-12, HER-2 and P53. The proliferation rate as measured by Ki-67 appeared higher in the lesions analyzed than in normal TDLUs. Columnar cell lesions in canine mammary gland are pathologically and immunophenotypically similar to those in human breast. This may suggest that dogs are a suitable model for the comparative study of noninvasive breast lesions

  19. Phase-Inductance-Based Position Estimation Method for Interior Permanent Magnet Synchronous Motors

    Directory of Open Access Journals (Sweden)

    Xin Qiu

    2017-12-01

    Full Text Available This paper presents a phase-inductance-based position estimation method for interior permanent magnet synchronous motors (IPMSMs. According to the characteristics of phase induction of IPMSMs, the corresponding relationship of the rotor position and the phase inductance is obtained. In order to eliminate the effect of the zero-sequence component of phase inductance and reduce the rotor position estimation error, the phase inductance difference is employed. With the iterative computation of inductance vectors, the position plane is further subdivided, and the rotor position is extracted by comparing the amplitudes of inductance vectors. To decrease the consumption of computer resources and increase the practicability, a simplified implementation is also investigated. In this method, the rotor position information is achieved easily, with several basic math operations and logical comparisons of phase inductances, without any coordinate transformation or trigonometric function calculation. Based on this position estimation method, the field orientated control (FOC strategy is established, and the detailed implementation is also provided. A series of experiment results from a prototype demonstrate the correctness and feasibility of the proposed method.

  20. Visible light communication based vehicle positioning using LED street light and rolling shutter CMOS sensors

    Science.gov (United States)

    Do, Trong Hop; Yoo, Myungsik

    2018-01-01

    This paper proposes a vehicle positioning system using LED street lights and two rolling shutter CMOS sensor cameras. In this system, identification codes for the LED street lights are transmitted to camera-equipped vehicles through a visible light communication (VLC) channel. Given that the camera parameters are known, the positions of the vehicles are determined based on the geometric relationship between the coordinates of the LEDs in the images and their real world coordinates, which are obtained through the LED identification codes. The main contributions of the paper are twofold. First, the collinear arrangement of the LED street lights makes traditional camera-based positioning algorithms fail to determine the position of the vehicles. In this paper, an algorithm is proposed to fuse data received from the two cameras attached to the vehicles in order to solve the collinearity problem of the LEDs. Second, the rolling shutter mechanism of the CMOS sensors combined with the movement of the vehicles creates image artifacts that may severely degrade the positioning accuracy. This paper also proposes a method to compensate for the rolling shutter artifact, and a high positioning accuracy can be achieved even when the vehicle is moving at high speeds. The performance of the proposed positioning system corresponding to different system parameters is examined by conducting Matlab simulations. Small-scale experiments are also conducted to study the performance of the proposed algorithm in real applications.

  1. Impact of model-based iterative reconstruction on low-contrast lesion detection and image quality in abdominal CT: a 12-reader-based comparative phantom study with filtered back projection at different tube voltages

    Energy Technology Data Exchange (ETDEWEB)

    Euler, Andre; Stieltjes, Bram; Eichenberger, Reto; Reisinger, Clemens; Hirschmann, Anna; Zaehringer, Caroline; Kircher, Achim; Streif, Matthias; Bucher, Sabine; Buergler, David; D' Errico, Luigia; Kopp, Sebastien; Wilhelm, Markus [University Hospital Basel, Clinic of Radiology and Nuclear Medicine, Basel (Switzerland); Szucs-Farkas, Zsolt [Hospital Centre of Biel, Institute of Radiology, Biel (Switzerland); Schindera, Sebastian T. [University Hospital Basel, Clinic of Radiology and Nuclear Medicine, Basel (Switzerland); Cantonal Hospital Aarau, Institute of Radiology, Aarau (Switzerland)

    2017-12-15

    To evaluate the impact of model-based iterative reconstruction (MBIR) on image quality and low-contrast lesion detection compared with filtered back projection (FBP) in abdominal computed tomography (CT) of simulated medium and large patients at different tube voltages. A phantom with 45 hypoattenuating lesions was placed in two water containers and scanned at 70, 80, 100, and 120 kVp. The 120-kVp protocol served as reference, and the volume CT dose index (CTDI{sub vol}) was kept constant for all protocols. The datasets were reconstructed with MBIR and FBP. Image noise and contrast-to-noise-ratio (CNR) were assessed. Low-contrast lesion detectability was evaluated by 12 radiologists. MBIR decreased the image noise by 24% and 27%, and increased the CNR by 30% and 29% for the medium and large phantoms, respectively. Lower tube voltages increased the CNR by 58%, 46%, and 16% at 70, 80, and 100 kVp, respectively, compared with 120 kVp in the medium phantom and by 9%, 18% and 12% in the large phantom. No significant difference in lesion detection rate was observed (medium: 79-82%; large: 57-65%; P > 0.37). Although MBIR improved quantitative image quality compared with FBP, it did not result in increased low-contrast lesion detection in abdominal CT at different tube voltages in simulated medium and large patients. (orig.)

  2. A region segmentation based algorithm for building a crystal position lookup table in a scintillation detector

    International Nuclear Information System (INIS)

    Wang Haipeng; Fan Xin; Yun Mingkai; Liu Shuangquan; Cao Xuexiang; Chai Pei; Shan Baoci

    2015-01-01

    In a scintillation detector, scintillation crystals are typically made into a 2-dimensional modular array. The location of incident gamma-ray needs be calibrated due to spatial response nonlinearity. Generally, position histograms-the characteristic flood response of scintillation detectors-are used for position calibration. In this paper, a position calibration method based on a crystal position lookup table which maps the inaccurate location calculated by Anger logic to the exact hitting crystal position has been proposed. Firstly, the position histogram is preprocessed, such as noise reduction and image enhancement. Then the processed position histogram is segmented into disconnected regions, and crystal marking points are labeled by finding the centroids of regions. Finally, crystal boundaries are determined and the crystal position lookup table is generated. The scheme is evaluated by the whole-body positron emission tomography (PET) scanner and breast dedicated single photon emission computed tomography scanner developed by the Institute of High Energy Physics, Chinese Academy of Sciences. The results demonstrate that the algorithm is accurate, efficient, robust and applicable to any configurations of scintillation detector. (authors)

  3. Presence of High-Risk HPV mRNA in Relation to Future High-Grade Lesions among High-Risk HPV DNA Positive Women with Minor Cytological Abnormalities.

    Directory of Open Access Journals (Sweden)

    Hanna Johansson

    Full Text Available Continuous expression of E6- and E7-oncogenes of high-risk human papillomavirus (HPV types is necessary for the development and maintenance of the dysplastic phenotype. The aim of the study was to determine the sensitivity and specificity of the APTIMA HPV mRNA assay (Hologic in predicting future development of high-grade cervical intraepithelial neoplasia (CIN among high-risk HPV-DNA-positive women with atypical squamous cells of undetermined significance (ASCUS or low-grade squamous epithelial lesion (LSIL cytology.Archived SurePath cervical samples of women ≥ 35 years of age with high-risk HPV DNA-positive ASCUS (n = 211 or LSIL, (n = 131 were tested for the presence of high-risk HPV E6/E7 mRNA using the APTIMA HPV assay, and the women were monitored for development of histopathologically verified CIN2+.Twenty-nine percent (61/211 of the women in the ASCUS group, and 34.3% (45/131 in the LSIL group developed CIN2+ within 4.5 years of follow-up. The prevalence of HPV mRNA was 90.0% (95% CI 85.9-94.0 among women with ASCUS and 95.4% (95% CI 91.8-99.0 among women with LSIL. The presence of HPV E6/E7 mRNA was associated with future development of CIN2+ among women with ASCUS and LSIL (p=0.02. The mRNA assay demonstrated high sensitivity in predicting future CIN2+ and CIN3 for index ASCUS (96.7%; 95% CI 87.6-99.4 and 100%; 95% CI 82.2-100, respectively and LSIL (97.8%, 95% CI 86.8-99.9 and 100%, 95% CI 79.9-100, respectively. The corresponding specificity was low, 12.7% (95% CI 7.9-19.3 and 5.8% (95% CI 2.2-13.6, for future CIN2+, respectively. The negative predictive value of the HPV mRNA assay for detecting future CIN3 was 100%, since no mRNA-negative woman developed CIN3 (0/27 as compared to 13.6% (43/315 of the mRNA-positive women (p = 0.03.The APTIMA mRNA assay demonstrated high sensitivity but low specificity in predicting future CIN2+ among women with minor cytological abnormalities. The assay had high negative predictive value for future

  4. Presence of High-Risk HPV mRNA in Relation to Future High-Grade Lesions among High-Risk HPV DNA Positive Women with Minor Cytological Abnormalities

    Science.gov (United States)

    Johansson, Hanna; Bjelkenkrantz, Kaj; Darlin, Lotten; Dilllner, Joakim; Forslund, Ola

    2015-01-01

    Objective Continuous expression of E6- and E7-oncogenes of high-risk human papillomavirus (HPV) types is necessary for the development and maintenance of the dysplastic phenotype. The aim of the study was to determine the sensitivity and specificity of the APTIMA HPV mRNA assay (Hologic) in predicting future development of high-grade cervical intraepithelial neoplasia (CIN) among high-risk HPV-DNA-positive women with atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous epithelial lesion (LSIL) cytology. Methods Archived SurePath cervical samples of women ≥ 35 years of age with high-risk HPV DNA-positive ASCUS (n = 211) or LSIL, (n = 131) were tested for the presence of high-risk HPV E6/E7 mRNA using the APTIMA HPV assay, and the women were monitored for development of histopathologically verified CIN2+. Results Twenty-nine percent (61/211) of the women in the ASCUS group, and 34.3% (45/131) in the LSIL group developed CIN2+ within 4.5 years of follow-up. The prevalence of HPV mRNA was 90.0% (95% CI 85.9-94.0) among women with ASCUS and 95.4% (95% CI 91.8-99.0) among women with LSIL. The presence of HPV E6/E7 mRNA was associated with future development of CIN2+ among women with ASCUS and LSIL (p=0.02). The mRNA assay demonstrated high sensitivity in predicting future CIN2+ and CIN3 for index ASCUS (96.7%; 95% CI 87.6-99.4 and 100%; 95% CI 82.2-100, respectively) and LSIL (97.8%, 95% CI 86.8-99.9 and 100%, 95% CI 79.9-100, respectively). The corresponding specificity was low, 12.7% (95% CI 7.9-19.3) and 5.8% (95% CI 2.2-13.6), for future CIN2+, respectively. The negative predictive value of the HPV mRNA assay for detecting future CIN3 was 100%, since no mRNA-negative woman developed CIN3 (0/27) as compared to 13.6% (43/315) of the mRNA-positive women (p = 0.03). Conclusion The APTIMA mRNA assay demonstrated high sensitivity but low specificity in predicting future CIN2+ among women with minor cytological abnormalities. The assay had

  5. Managing Carious Lesions

    DEFF Research Database (Denmark)

    Innes, N P T; Frencken, J E; Bjørndal, L

    2016-01-01

    Variation in the terminology used to describe clinical management of carious lesions has contributed to a lack of clarity in the scientific literature and beyond. In this article, the International Caries Consensus Collaboration presents 1) issues around terminology, a scoping review of current...... manifestations to the histopathology, we have based the terminology around the clinical consequences of disease (soft, leathery, firm, and hard dentine). Approaches to carious tissue removal are defined: 1)selective removal of carious tissue-includingselective removal to soft dentineandselective removal to firm...

  6. Acute periodontal lesions.

    Science.gov (United States)

    Herrera, David; Alonso, Bettina; de Arriba, Lorenzo; Santa Cruz, Isabel; Serrano, Cristina; Sanz, Mariano

    2014-06-01

    This review provides updates on acute conditions affecting the periodontal tissues, including abscesses in the periodontium, necrotizing periodontal diseases and other acute conditions that cause gingival lesions with acute presentation, such as infectious processes not associated with oral bacterial biofilms, mucocutaneous disorders and traumatic and allergic lesions. A periodontal abscess is clinically important because it is a relatively frequent dental emergency, it can compromise the periodontal prognosis of the affected tooth and bacteria within the abscess can spread and cause infections in other body sites. Different types of abscesses have been identified, mainly classified by their etiology, and there are clear differences between those affecting a pre-existing periodontal pocket and those affecting healthy sites. Therapy for this acute condition consists of drainage and tissue debridement, while an evaluation of the need for systemic antimicrobial therapy will be made for each case, based on local and systemic factors. The definitive treatment of the pre-existing condition should be accomplished after the acute phase is controlled. Necrotizing periodontal diseases present three typical clinical features: papilla necrosis, gingival bleeding and pain. Although the prevalence of these diseases is not high, their importance is clear because they represent the most severe conditions associated with the dental biofilm, with very rapid tissue destruction. In addition to bacteria, the etiology of necrotizing periodontal disease includes numerous factors that alter the host response and predispose to these diseases, namely HIV infection, malnutrition, stress or tobacco smoking. The treatment consists of superficial debridement, careful mechanical oral hygiene, rinsing with chlorhexidine and daily re-evaluation. Systemic antimicrobials may be used adjunctively in severe cases or in nonresponding conditions, being the first option metronidazole. Once the acute

  7. An online x-ray based position validation system for prostate hypofractionated radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Arumugam, Sankar, E-mail: Sankar.Arumugam@sswahs.nsw.gov.au; Xing, Aitang [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute, New South Wales 2170 (Australia); Sidhom, Mark [Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres, New South Wales 2170 (Australia); Holloway, Lois [Department of Medical Physics, Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute, New South Wales 2170 (Australia); Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales 2522 (Australia); South Western Clinical School, University of New South Wales, Sydney, New South Wales 2052 (Australia); Institute of Medical Physics, School of Physics, University of Sydney, Sydney, New South Wales 2006 (Australia)

    2016-02-15

    Purpose: Accurate positioning of the target volume during treatment is paramount for stereotactic body radiation therapy (SBRT). In this work, the authors present the development of an in-house software tool to verify target position with an Elekta-Synergy linear accelerator using kV planar images acquired during treatment delivery. Methods: In-house software, SeedTracker, was developed in MATLAB to perform the following three functions: 1. predict intended seed positions in a planar view perpendicular to any gantry angle, simulating a portal imaging device, from the 3D seed co-ordinates derived from the treatment planning system; 2. autosegment seed positions in kV planar images; and 3. report the position shift based on the seed positions in the projection images. The performance of SeedTracker was verified using a CIRS humanoid phantom (CIRS, VA, USA) implanted with three Civco gold seed markers (Civco, IA, USA) in the prostate. The true positive rate of autosegmentation (TPR{sub seg}) and the accuracy of the software in alerting the user when the isocenter position was outside the tolerance (TPR{sub trig}) were studied. Two-dimensional and 3D static position offsets introduced to the humanoid phantom and 3D dynamic offsets introduced to a gel phantom containing gold seeds were used for evaluation of the system. Results: SeedTracker showed a TPR{sub seg} of 100% in the humanoid phantom for projection images acquired at all angles except in the ranges of 80°–100° and 260°–280° where seeds are obscured by anatomy. This resulted in a TPR{sub trig} of 88% over the entire treatment range for considered 3D static offsets introduced to the phantom. For 2D static offsets where the position offsets were only introduced in the anterior–posterior and lateral directions, the TPR{sub trig} of SeedTracker was limited by both seed detectability and positional offset. SeedTracker showed a false positive trigger in the projection angle range between 130°–170° and

  8. Reducing false-positive incidental findings with ensemble genotyping and logistic regression based variant filtering methods.

    Science.gov (United States)

    Hwang, Kyu-Baek; Lee, In-Hee; Park, Jin-Ho; Hambuch, Tina; Choe, Yongjoon; Kim, MinHyeok; Lee, Kyungjoon; Song, Taemin; Neu, Matthew B; Gupta, Neha; Kohane, Isaac S; Green, Robert C; Kong, Sek Won

    2014-08-01

    As whole genome sequencing (WGS) uncovers variants associated with rare and common diseases, an immediate challenge is to minimize false-positive findings due to sequencing and variant calling errors. False positives can be reduced by combining results from orthogonal sequencing methods, but costly. Here, we present variant filtering approaches using logistic regression (LR) and ensemble genotyping to minimize false positives without sacrificing sensitivity. We evaluated the methods using paired WGS datasets of an extended family prepared using two sequencing platforms and a validated set of variants in NA12878. Using LR or ensemble genotyping based filtering, false-negative rates were significantly reduced by 1.1- to 17.8-fold at the same levels of false discovery rates (5.4% for heterozygous and 4.5% for homozygous single nucleotide variants (SNVs); 30.0% for heterozygous and 18.7% for homozygous insertions; 25.2% for heterozygous and 16.6% for homozygous deletions) compared to the filtering based on genotype quality scores. Moreover, ensemble genotyping excluded > 98% (105,080 of 107,167) of false positives while retaining > 95% (897 of 937) of true positives in de novo mutation (DNM) discovery in NA12878, and performed better than a consensus method using two sequencing platforms. Our proposed methods were effective in prioritizing phenotype-associated variants, and an ensemble genotyping would be essential to minimize false-positive DNM candidates. © 2014 WILEY PERIODICALS, INC.

  9. Vehicle Position Estimation Based on Magnetic Markers: Enhanced Accuracy by Compensation of Time Delays

    Directory of Open Access Journals (Sweden)

    Yeun-Sub Byun

    2015-11-01

    Full Text Available The real-time recognition of absolute (or relative position and orientation on a network of roads is a core technology for fully automated or driving-assisted vehicles. This paper presents an empirical investigation of the design, implementation, and evaluation of a self-positioning system based on a magnetic marker reference sensing method for an autonomous vehicle. Specifically, the estimation accuracy of the magnetic sensing ruler (MSR in the up-to-date estimation of the actual position was successfully enhanced by compensating for time delays in signal processing when detecting the vertical magnetic field (VMF in an array of signals. In this study, the signal processing scheme was developed to minimize the effects of the distortion of measured signals when estimating the relative positional information based on magnetic signals obtained using the MSR. In other words, the center point in a 2D magnetic field contour plot corresponding to the actual position of magnetic markers was estimated by tracking the errors between pre-defined reference models and measured magnetic signals. The algorithm proposed in this study was validated by experimental measurements using a test vehicle on a pilot network of roads. From the results, the positioning error was found to be less than 0.04 m on average in an operational test.

  10. A Position Sensorless Control Method for SRM Based on Variation of Phase Inductance

    Science.gov (United States)

    Komatsuzaki, Akitomo; Miki, Ichiro

    Switched reluctance motor (SRM) drives are suitable for variable speed industrial applications because of the simple structure and high-speed capability. However, it is necessary to detect the rotor position with a position sensor attached to the motor shaft. The use of the sensor increases the cost of the drive system and machine size, and furthermore the reliability of the system is reduced. Therefore, several approaches to eliminate the position sensor have already been reported. In this paper, a position sensorless control method based on the variation of the phase inductance is described. The phase inductance regularly varies with the rotor position. The SRM is controlled without the position sensor using the de-fluxing period and the phase inductance. The turn-off timing is determined by computing the difference of angle between the sampling point and the aligned point and the variation of angle during the de-fluxing period. In the magnetic saturation region, the phase inductance at the current when the effect of the saturation starts is computed and the sensorless control can be carried out using this inductance. Experimental results show that the SRM is well controlled without the position sensor using the proposed method.

  11. A Wireless Sensor Network Based Personnel Positioning Scheme in Coal Mines with Blind Areas

    Science.gov (United States)

    Liu, Zhigao; Li, Chunwen; Wu, Danchen; Dai, Wenhan; Geng, Shaobo; Ding, Qingqing

    2010-01-01

    This paper proposes a novel personnel positioning scheme for a tunnel network with blind areas, which compared with most existing schemes offers both low-cost and high-precision. Based on the data models of tunnel networks, measurement networks and mobile miners, the global positioning method is divided into four steps: (1) calculate the real time personnel location in local areas using a location engine, and send it to the upper computer through the gateway; (2) correct any localization errors resulting from the underground tunnel environmental interference; (3) determine the global three-dimensional position by coordinate transformation; (4) estimate the personnel locations in the blind areas. A prototype system constructed to verify the positioning performance shows that the proposed positioning system has good reliability, scalability, and positioning performance. In particular, the static localization error of the positioning system is less than 2.4 m in the underground tunnel environment and the moving estimation error is below 4.5 m in the corridor environment. The system was operated continuously over three months without any failures. PMID:22163446

  12. A wireless sensor network based personnel positioning scheme in coal mines with blind areas.

    Science.gov (United States)

    Liu, Zhigao; Li, Chunwen; Wu, Danchen; Dai, Wenhan; Geng, Shaobo; Ding, Qingqing

    2010-01-01

    This paper proposes a novel personnel positioning scheme for a tunnel network with blind areas, which compared with most existing schemes offers both low-cost and high-precision. Based on the data models of tunnel networks, measurement networks and mobile miners, the global positioning method is divided into four steps: (1) calculate the real time personnel location in local areas using a location engine, and send it to the upper computer through the gateway; (2) correct any localization errors resulting from the underground tunnel environmental interference; (3) determine the global three-dimensional position by coordinate transformation; (4) estimate the personnel locations in the blind areas. A prototype system constructed to verify the positioning performance shows that the proposed positioning system has good reliability, scalability, and positioning performance. In particular, the static localization error of the positioning system is less than 2.4 m in the underground tunnel environment and the moving estimation error is below 4.5 m in the corridor environment. The system was operated continuously over three months without any failures.

  13. High-precision positioning system of four-quadrant detector based on the database query

    Science.gov (United States)

    Zhang, Xin; Deng, Xiao-guo; Su, Xiu-qin; Zheng, Xiao-qiang

    2015-02-01

    The fine pointing mechanism of the Acquisition, Pointing and Tracking (APT) system in free space laser communication usually use four-quadrant detector (QD) to point and track the laser beam accurately. The positioning precision of QD is one of the key factors of the pointing accuracy to APT system. A positioning system is designed based on FPGA and DSP in this paper, which can realize the sampling of AD, the positioning algorithm and the control of the fast swing mirror. We analyze the positioning error of facular center calculated by universal algorithm when the facular energy obeys Gauss distribution from the working principle of QD. A database is built by calculation and simulation with MatLab software, in which the facular center calculated by universal algorithm is corresponded with the facular center of Gaussian beam, and the database is stored in two pieces of E2PROM as the external memory of DSP. The facular center of Gaussian beam is inquiry in the database on the basis of the facular center calculated by universal algorithm in DSP. The experiment results show that the positioning accuracy of the high-precision positioning system is much better than the positioning accuracy calculated by universal algorithm.

  14. DIFFERENCES BETWEEN FOOTBALL PLAYERS OF DIFFERENT GAMING POSITIONS BASED ON SOME BASIC AND SPECIFIC MOTOR ABILITIES

    Directory of Open Access Journals (Sweden)

    Bogdan Tomić

    2011-09-01

    Full Text Available Based on the structure competition activities, and its character can be defined as a hypothetical model of the anthropological characteristics of football players of different gaming positions. Based on hypothetical models of different football players' position can make a division into two groups of players based on game systems that are commonly used in modern football, which is 4-4-2, and the common anthropological characteristics, structure and nature of activities carried out by during the game, so the first group consists of players with smaller volumes of engagement in the game (goalkeeper, two central defenders and two strikers and the second group 190 CRNOGORSKA SPORTSKA AKADEMIJA, „Sport Mont“ časopis br. 31,32,33. consists of players with greater scope to engage in the game (two foreign players and four defensive midfielder (midfielder . The aim is to determine the difference between players of different players' positions on the basis of some basic and specific motor abilities. The sample of 206 football players aged 18 ± 0.5 years is divided into 5 subsamples according to examinees gaming position: forwarders (45, midfield players (47, defenders (41, central defenders (44 and goalkeepers (29. The battery of 16 tests (in which the results are expressed in distance and time - metric. It can be concluded that there are differences between players of different players' positions on the team in relation to the basic and specific motor skills.

  15. A laser interferometer for measuring straightness and its position based on heterodyne interferometry

    International Nuclear Information System (INIS)

    Chen Benyong; Zhang Enzheng; Yan Liping; Li Chaorong; Tang Wuhua; Feng Qibo

    2009-01-01

    Not only the magnitude but also the position of straightness errors are of concern to users. However, current laser interferometers used for measuring straightness seldom give the relative position of the straightness error. To solve this problem, a laser interferometer for measuring straightness and its position based on heterodyne interferometry is proposed. The optical configuration of the interferometer is designed and the measurement principle is analyzed theoretically. Two experiments were carried out. The first experiment verifies the validity and repeatability of the interferometer by measuring a linear stage. Also, the second one for measuring a flexure-hinge stage demonstrates that the interferometer is capable of nanometer measurement accuracy. These results show that this interferometer has advantages of simultaneously measuring straightness error and the relative position with high precision, and a compact structure.

  16. Real-Time Hand Position Sensing Technology Based on Human Body Electrostatics

    Directory of Open Access Journals (Sweden)

    Kai Tang

    2018-05-01

    Full Text Available Non-contact human-computer interactions (HCI based on hand gestures have been widely investigated. Here, we present a novel method to locate the real-time position of the hand using the electrostatics of the human body. This method has many advantages, including a delay of less than one millisecond, low cost, and does not require a camera or wearable devices. A formula is first created to sense array signals with five spherical electrodes. Next, a solving algorithm for the real-time measured hand position is introduced and solving equations for three-dimensional coordinates of hand position are obtained. A non-contact real-time hand position sensing system was established to perform verification experiments, and the principle error of the algorithm and the systematic noise were also analyzed. The results show that this novel technology can determine the dynamic parameters of hand movements with good robustness to meet the requirements of complicated HCI.

  17. Teleoperation environment based on virtual reality. Application of two-planes method for position measurement

    International Nuclear Information System (INIS)

    Yoshikawa, Hidekazu; Tezuka, Tetsuo; Inoue, Ryuji

    1998-01-01

    A teleoperation system based on virtual environment (VE) is an emergent technology for operating a robot in remote or hazardous environment. We have developed a VE-based teleoperation system for robot-arm manipulation in a simplified real world. The VE for manipulating the robot arm is constructed by measuring the 3D positions of the objects around the robot arm by motion-stereo method. The 3D position is estimated by using two-(calibration) planes method based on images captured by the CCD camera on the robot-arm, since the two-planes method does not need pin-hole-model assumption to the camera system. The precision of this 3D-measurement is evaluated through experiments and then derived is the theoretical model to the error in the measurement. This measurement system is applied to VE-based teleoperation experiment for Peg-in-hole practice by the robot arm. (author)

  18. Algorithm of reducing the false positives in IDS based on correlation Analysis

    Science.gov (United States)

    Liu, Jianyi; Li, Sida; Zhang, Ru

    2018-03-01

    This paper proposes an algorithm of reducing the false positives in IDS based on correlation Analysis. Firstly, the algorithm analyzes the distinguishing characteristics of false positives and real alarms, and preliminary screen the false positives; then use the method of attribute similarity clustering to the alarms and further reduces the amount of alarms; finally, according to the characteristics of multi-step attack, associated it by the causal relationship. The paper also proposed a reverse causation algorithm based on the attack association method proposed by the predecessors, turning alarm information into a complete attack path. Experiments show that the algorithm simplifies the number of alarms, improve the efficiency of alarm processing, and contribute to attack purposes identification and alarm accuracy improvement.

  19. IWKNN: An Effective Bluetooth Positioning Method Based on Isomap and WKNN

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2016-01-01

    Full Text Available Recently, Bluetooth-based indoor positioning has become a hot research topic. However, the instability of Bluetooth RSSI (Received Signal Strength Indicator promotes a huge challenge in localization accuracy. To improve the localization accuracy, this paper measures the distance of RSSI vectors on their low-dimensional manifold and proposes a novel positioning method IWKNN (Isomap-based Weighted K-Nearest Neighbor. The proposed method firstly uses Isomap to generate low-dimensional embedding for RSSI vectors. Then, the distance of two given RSSI vectors is measured by Euclidean distance of their low-dimensional embeddings. Finally, the position is calculated by WKNN. Experiment indicates that the proposed approach is more robust and accurate.

  20. Indoor anti-occlusion visible light positioning systems based on particle filtering

    Science.gov (United States)

    Jiang, Meng; Huang, Zhitong; Li, Jianfeng; Zhang, Ruqi; Ji, Yuefeng

    2015-04-01

    As one of the most popular categories of mobile services, a rapid growth of indoor location-based services has been witnessed over the past decades. Indoor positioning methods based on Wi-Fi, radio-frequency identification or Bluetooth are widely commercialized; however, they have disadvantages such as low accuracy or high cost. An emerging method using visible light is under research recently. The existed visible light positioning (VLP) schemes using carrier allocation, time allocation and multiple receivers all have limitations. This paper presents a novel mechanism using particle filtering in VLP system. By this method no additional devices are needed and the occlusion problem in visible light would be alleviated which will effectively enhance the flexibility for indoor positioning.

  1. Restoring the lattice of Si-based atom probe reconstructions for enhanced information on dopant positioning.

    Science.gov (United States)

    Breen, Andrew J; Moody, Michael P; Ceguerra, Anna V; Gault, Baptiste; Araullo-Peters, Vicente J; Ringer, Simon P

    2015-12-01

    The following manuscript presents a novel approach for creating lattice based models of Sb-doped Si directly from atom probe reconstructions for the purposes of improving information on dopant positioning and directly informing quantum mechanics based materials modeling approaches. Sophisticated crystallographic analysis techniques are used to detect latent crystal structure within the atom probe reconstructions with unprecedented accuracy. A distortion correction algorithm is then developed to precisely calibrate the detected crystal structure to the theoretically known diamond cubic lattice. The reconstructed atoms are then positioned on their most likely lattice positions. Simulations are then used to determine the accuracy of such an approach and show that improvements to short-range order measurements are possible for noise levels and detector efficiencies comparable with experimentally collected atom probe data. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Probabilistic Multi-Sensor Fusion Based Indoor Positioning System on a Mobile Device

    Directory of Open Access Journals (Sweden)

    Xiang He

    2015-12-01

    Full Text Available Nowadays, smart mobile devices include more and more sensors on board, such as motion sensors (accelerometer, gyroscope, magnetometer, wireless signal strength indicators (WiFi, Bluetooth, Zigbee, and visual sensors (LiDAR, camera. People have developed various indoor positioning techniques based on these sensors. In this paper, the probabilistic fusion of multiple sensors is investigated in a hidden Markov model (HMM framework for mobile-device user-positioning. We propose a graph structure to store the model constructed by multiple sensors during the offline training phase, and a multimodal particle filter to seamlessly fuse the information during the online tracking phase. Based on our algorithm, we develop an indoor positioning system on the iOS platform. The experiments carried out in a typical indoor environment have shown promising results for our proposed algorithm and system design.

  3. Human papillomavirus in anal biopsy tissues and liquid-based cytology samples of HIV-positive and HIV-negative Thai men who have sex with men

    Directory of Open Access Journals (Sweden)

    Tippawan Pankam

    2017-06-01

    Full Text Available Background: Men who have sex with men (MSM are at high risk of developing human papillomavirus (HPV-related anal cancer. We compared HPV genotypes in anal tissues (Bx and anal liquid-based cytology fluid (LBC from HIV-positive and HIV-negative MSM. Methods: Bx (32 normal, 41 low-grade squamous intraepithelial lesions (LSIL and 22 high-grade squamous intraepithelial lesions (HSIL, along with LBC from the same visit, were selected from 61 HIV-positive and 34 HIV-negative MSM who enrolled into a prospective cohort in Bangkok, Thailand. HPV genotyping was performed on Bx and LBC. Results: Any HPV and high-risk HPV (HR-HPV prevalence were 63.2% and 60.0% in Bx and 71.6% and 62.1% in LBC, respectively. HIV-positive MSM had higher rates of HR-HPV genotypes detection (70.5% vs. 47.1%, p=0.03 in LBC than HIV-negative MSM. HPV16 (27% was the most common HR-HPV found in HSIL tissue. In HIV-positive MSM, the frequency of HR-HPV detection increased with histopathologic grading in both Bx and LBC samples. HSIL was associated with the presence of any HR-HPV(OR 7.6 (95%CI 1.8–31.9; P=0.006 in LBC and in Bx((OR 5.6 (95%CI 1.4–22.7; P=0.02. Conclusions: Our data strongly support the integration of HR-HPV screening on LBC samples, along with HPV vaccination, into an anal cancer prevention program. Keywords: Human papillomavirus, Anal tissues, Men who have sex with men, HIV, Thailand

  4. Oropharynx lesion biopsy

    Science.gov (United States)

    ... as papilloma) Fungal infections (such as candida) Histoplasmosis Oral lichen planus Precancerous sore (leukoplakia) Viral infections (such as Herpes simplex) Risks Risks of the procedure may ... Throat lesion biopsy; Biopsy - mouth or throat; Mouth lesion biopsy; Oral cancer - biopsy ...

  5. Seamless Indoor/Outdoor Positioning Handover for Location-Based Services in Streamspin

    DEFF Research Database (Denmark)

    Hansen, Rene; Wind, Rico; Jensen, Christian Søndergaard

    2009-01-01

    the delivery of truly ubiquitous location-based services by integrating GPS and Wi-Fi location fingerprinting. The paper puts focus on key aspects of the seamless handover between outdoor to indoor positioning. Several different handover solutions are presented,and their applicability is evaluated with respect...

  6. An Analysis of CONUS Based Deployment of Pseudolites for Positioning, Navigation and Timing (PNT) Systems

    Science.gov (United States)

    2015-09-17

    incorporate a master “ time - keeper ” or reference transmitter that other receiver/transmitters can synchronize with. Currently, GPS provides about 1 m...AN ANALYSIS OF CONUS BASED DEPLOYMENT OF PSEUDOLITES FOR POSITIONING, NAVIGATION AND TIMING (PNT...NAVIGATION AND TIMING (PNT) SYSTEMS THESIS Presented to the Faculty Department of Systems Engineering and Management Graduate School of

  7. Training data representation in a neural based robot position estimation system

    International Nuclear Information System (INIS)

    Taraglio, S.; Di Fonzo, F.; Burrascano, P.

    1997-03-01

    The vision subsystem of an autonomous vehicle is studies. It is based on a multi layer perceptron that uses TV images to estimate the position of the vehicle. A comparative study of the effects of output data representation and input data processing is presented and discussed

  8. What does it cost to deliver information using position-based beaconless forwarding protocols?

    KAUST Repository

    Bader, Ahmed

    2012-04-01

    Beaconless position-based forwarding protocols have recently evolved as a promising solution for packet forwarding in wireless sensor networks. Quite a few variants of this class of forwarding protocols have been proposed over the years. One common observation is that they have all been evaluated from the perspective of a single node. Although useful, but a solid understanding of the end-to-end performance is still necessary. In this paper, we shed light on the end-to-end performance of beaconless position-based protocols along three distinct dimensions: energy, latency, and back-off probability. The latter is used as a direct indicator of the network\\'s transport capacity. Consequently, we are able to provide an elaborate response to the question: what does it really cost to deliver a packet in a wireless sensor network using position-based beaconless forwarding protocols? In responding to this question, we highlighted the different performance tradeoffs inherent to beaconless position-based protocols. Furthermore, some operational recommendations are also provided. © 2012 IEEE.

  9. Kinetic scrolling-based position mapping for haptic teleoperation of unmanned aerial vehicles

    NARCIS (Netherlands)

    Ruesch, A.; Mersha, A.Y.; Stramigioli, Stefano; Carloni, Raffaella

    In this paper, we present a haptic teleoperation control algorithm for unmanned aerial vehicles, applying a kinetic scrolling-based position mapping. The proposed algorithm overcomes the master workspace limitations and enables to teleoperate the aerial vehicle in unbounded workspace in a fast and

  10. What does it cost to deliver information using position-based beaconless forwarding protocols?

    KAUST Repository

    Bader, Ahmed; Abed-Meraim, Karim; Alouini, Mohamed-Slim

    2012-01-01

    Beaconless position-based forwarding protocols have recently evolved as a promising solution for packet forwarding in wireless sensor networks. Quite a few variants of this class of forwarding protocols have been proposed over the years. One common observation is that they have all been evaluated from the perspective of a single node. Although useful, but a solid understanding of the end-to-end performance is still necessary. In this paper, we shed light on the end-to-end performance of beaconless position-based protocols along three distinct dimensions: energy, latency, and back-off probability. The latter is used as a direct indicator of the network's transport capacity. Consequently, we are able to provide an elaborate response to the question: what does it really cost to deliver a packet in a wireless sensor network using position-based beaconless forwarding protocols? In responding to this question, we highlighted the different performance tradeoffs inherent to beaconless position-based protocols. Furthermore, some operational recommendations are also provided. © 2012 IEEE.

  11. Positional skull deformation in infants: heading towards evidence-based practice

    NARCIS (Netherlands)

    van Wijk, Renske

    2014-01-01

    The shape of a young infant’s skull can deform as a result of prolonged external forces. The prevalence of positional skull deformation increased dramatically during the last decades. The primary aim of this dissertation was to provide a stronger evidence base for the treatment of skull deformation.

  12. Inverse spiking filter based acquisition enhancement in software based global positioning system receiver

    Directory of Open Access Journals (Sweden)

    G. Arul Elango

    2015-01-01

    Full Text Available The lower visibility of the satellite in the acquisition stage of a GPS receiver under worst noisy situation leads to reacquisition of the data and thereby takes a longer time to obtain the first position fix. If the impulse noise affects the GPS signal, the conventional ways of acquiring the satellites do not guarantee to meet the minimum requirement of four satellites to find the user position. The performance of GPS receiver acquisition can be improved in the low SNR level using inverse spiking filtering technique. In the proposed method, the estimate of the desired GPS L1 signal corrupted by impulse noise (gn is obtained by the prediction error filter (hopt, which is the optimum inverse filter that reshapes the noisy signal (yn into a desired GPS signal (xn. In the proposed method, to detect the visible satellites under weak signal conditions the traditional differential coherent approach is combined with the inverse spiking filter method to increase the number of visible satellites and to avoid the reacquisition process. Montecarlo simulation is carried out to assess the performance of the proposed method for C/N0 of 20 dB-Hz and results indicate that the modified differential coherent method effectively excises the noise with 90% probability of detection. Subsequently tracking operation is also tested to confirm the acquisition performance by demodulating the navigation data successfully.

  13. Comparison of SPECT/CT and MRI in diagnosing symptomatic lesions in ankle and foot pain patients: diagnostic performance and relation to lesion type.

    Science.gov (United States)

    Ha, Seunggyun; Hong, Sung Hwan; Paeng, Jin Chul; Lee, Dong Yeon; Cheon, Gi Jeong; Arya, Amitabh; Chung, June-Key; Lee, Dong Soo; Kang, Keon Wook

    2015-01-01

    The purpose of this study was to compare the diagnostic performance of SPECT/CT and MRI in patients with ankle and foot pain, with regard to the lesion types. Fifty consecutive patients with ankle and foot pain, who underwent 99mTc-MDP SPECT/CT and MRI, were retrospectively enrolled in this study. Symptomatic lesions were determined based on clinical examination and response to treatment. On MRI and SPECT/CT, detected lesions were classified as bone, ligament/tendon, and joint lesions. Uptake on SPECT/CT was assessed using a 4-grade system. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of SPECT/CT and MRI were evaluated in all detected lesions and each lesion type. Diagnostic value of uptake grade was analyzed using receiver-operating characteristics (ROC) curve analysis, and diagnostic performance was compared using Chi-square or McNemar tests. In overall lesions, the sensitivity, PPV and NPV of SPECT/CT for symptomatic lesions were 93%, 56%, 91%, and they were 98%, 48%, 95% for MRI. There was no significant difference between SPECT/CT and MRI. However, the specificity of SPECT/CT was significantly higher than that of MRI (48% versus 24%, P = 0.016). Uptake grade on SPECT/CT was significantly higher in symptomatic lesions (P diagnostic performance for symptomatic lesions in ankle and foot pain patients. SPECT/CT and MRI exhibit different diagnostic specificity in different lesion types. SPECT/CT may be used as a complementary imaging method to MRI for enhancing diagnostic specificity.

  14. A novel capacitive absolute positioning sensor based on time grating with nanometer resolution

    Science.gov (United States)

    Pu, Hongji; Liu, Hongzhong; Liu, Xiaokang; Peng, Kai; Yu, Zhicheng

    2018-05-01

    The present work proposes a novel capacitive absolute positioning sensor based on time grating. The sensor includes a fine incremental-displacement measurement component combined with a coarse absolute-position measurement component to obtain high-resolution absolute positioning measurements. A single row type sensor was proposed to achieve fine displacement measurement, which combines the two electrode rows of a previously proposed double-row type capacitive displacement sensor based on time grating into a single row. To achieve absolute positioning measurement, the coarse measurement component is designed as a single-row type displacement sensor employing a single spatial period over the entire measurement range. In addition, this component employs a rectangular induction electrode and four groups of orthogonal discrete excitation electrodes with half-sinusoidal envelope shapes, which were formed by alternately extending the rectangular electrodes of the fine measurement component. The fine and coarse measurement components are tightly integrated to form a compact absolute positioning sensor. A prototype sensor was manufactured using printed circuit board technology for testing and optimization of the design in conjunction with simulations. Experimental results show that the prototype sensor achieves a ±300 nm measurement accuracy with a 1 nm resolution over a displacement range of 200 mm when employing error compensation. The proposed sensor is an excellent alternative to presently available long-range absolute nanometrology sensors owing to its low cost, simple structure, and ease of manufacturing.

  15. Incidental enhancing lesions found on preoperative breast MRI: management and role of second-look ultrasound.

    Science.gov (United States)

    Luciani, M L; Pediconi, F; Telesca, M; Vasselli, F; Casali, V; Miglio, E; Passariello, R; Catalano, C

    2011-09-01

    This study prospectively assessed second-look ultrasound (US) for the evaluation of incidental enhancing lesions identified on preoperative breast magnetic resonance imaging (MRI). Between 2004 and 2007, 182 patients with malignant breast lesions detected on US and/or X-ray mammography and confirmed by cytology/histology underwent preoperative breast contrast-enhanced (CE)-MRI. Patients with incidental lesions on breast MRI underwent second-look high-resolution US directed at the site of the incidental finding. Diagnosis of incidental lesions was based on biopsy or 24-month follow-up. Breast MRI detected 55 additional lesions in 46/182 (25.2%) patients. Forty-two of 55 (76.3%) lesions were detected on second-look US in 38/46 (82.6%) patients. Malignancy was confirmed for 24/42 (57.1%) correlate lesions compared with 7/13 (53.8%) noncorrelate lesions. Second-look US depicted 8/9 (88.8%) Breast Imaging Reporting and Data System (BI-RADS) 5, 16/22 (72.7%) BI-RADS 4 and 18/24 (75%) BI-RADS 3 lesions. Sensitivity, specificity, accuracy and positive and negative predictive values for lesion detection/diagnosis was 100%, 88.9%, 94.6%, 90.3% and 100% for MRI and 64.3%, 70.4%, 67.3%, 69.2% and 65.5% for second-look US. Improved performance for US was obtained when masslike lesions only were considered. Second-look US is a confirmatory method for incidental findings on breast MRI, particularly for mass-like lesions.

  16. Design and performance analysis of position-based impedance control for an electrohydrostatic actuation system

    Directory of Open Access Journals (Sweden)

    Yongling FU

    2018-03-01

    Full Text Available Electrohydrostatic actuator (EHA is a type of power-by-wire actuator that is widely implemented in the aerospace industry for flight control, landing gears, thrust reversers, thrust vector control, and space robots. This paper presents the development and evaluation of position-based impedance control (PBIC for an EHA. Impedance control provides the actuator with compliance and facilitates the interaction with the environment. Most impedance control applications utilize electrical or valve-controlled hydraulic actuators, whereas this work realizes impedance control via a compact and efficient EHA. The structures of the EHA and PBIC are firstly introduced. A mathematical model of the actuation system is established, and values of its coefficients are identified by particle swarm optimization. This model facilitates the development of a position controller and the selection of target impedance parameters. A nonlinear proportional-integral position controller is developed for the EHA to achieve the accurate positioning requirement of PBIC. The controller compensates for the adverse effect of stiction, and a position accuracy of 0.08 mm is attained. Various experimental results are presented to verify the applicability of PBIC to the EHA. The compliance of the actuator is demonstrated in an impact test. Keywords: Actuation system, Aerospace, Electrohydrostatic actuator, Force control, Nonlinear dynamics, Particle swarm optimization, Position control

  17. A Kind of Single-frequency Precise Point Positioning Algorithm Based on the Raw Observations

    Directory of Open Access Journals (Sweden)

    WANG Li

    2015-01-01

    Full Text Available A kind of single-frequency precise point positioning (PPP algorithm based on the raw observations is presented in this paper. By this algorithm, the ionospheric delays were corrected efficiently by means of adding the ionospheric delay prior information and the virtual observation equations with the spatial and temporal constraints, and they were estimated as the unknown parameters simultaneously with other positioning parameters. Then, a dataset of 178 International GNSS Service (IGS stations at day 72 in 2012 was used to evaluate the convergence speed, the positioning accuracy and the accuracy of the retrieved ionospheric VTEC. The series of results have shown that the convergence speed and stability of the new algorithm are much better than the traditional PPP algorithm, and the positioning accuracy of about 2-3 cm and 2-3 dm can be achieved respectively for static and kinematic positioning with the single-frequency observations' daily solution. The average bias of ionospheric total electron content retrieved by the single-frequency PPP and dual-frequency PPP is less than 5 TECU. So the ionospheric total electron content can be used as a kind of auxiliary products in GPS positioning.

  18. Analysis of RDSS positioning accuracy based on RNSS wide area differential technique

    Science.gov (United States)

    Xing, Nan; Su, RanRan; Zhou, JianHua; Hu, XiaoGong; Gong, XiuQiang; Liu, Li; He, Feng; Guo, Rui; Ren, Hui; Hu, GuangMing; Zhang, Lei

    2013-10-01

    The BeiDou Navigation Satellite System (BDS) provides Radio Navigation Service System (RNSS) as well as Radio Determination Service System (RDSS). RDSS users can obtain positioning by responding the Master Control Center (MCC) inquiries to signal transmitted via GEO satellite transponder. The positioning result can be calculated with elevation constraint by MCC. The primary error sources affecting the RDSS positioning accuracy are the RDSS signal transceiver delay, atmospheric trans-mission delay and GEO satellite position error. During GEO orbit maneuver, poor orbit forecast accuracy significantly impacts RDSS services. A real-time 3-D orbital correction method based on wide-area differential technique is raised to correct the orbital error. Results from the observation shows that the method can successfully improve positioning precision during orbital maneuver, independent from the RDSS reference station. This improvement can reach 50% in maximum. Accurate calibration of the RDSS signal transceiver delay precision and digital elevation map may have a critical role in high precise RDSS positioning services.

  19. Autonomous Positioning Techniques Based on Cramér-Rao Lower Bound Analysis

    Directory of Open Access Journals (Sweden)

    Urruela Andreu

    2006-01-01

    Full Text Available We consider the problem of autonomously locating a number of asynchronous sensor nodes in a wireless network. A strong focus lies on reducing the processing resources needed to solve the relative positioning problem, an issue of great interest in resource-constrained wireless sensor networks. In the first part of the paper, based on a well-known derivation of the Cramér-Rao lower bound for the asynchronous sensor positioning problem, we are able to construct optimal preprocessing methods for sensor clock-offset cancellation. A cancellation of unknown clock-offsets from the asynchronous positioning problem reduces processing requirements, and, under certain reasonable assumptions, allows for statistically efficient distributed positioning algorithms. Cramér-Rao lower bound theory may also be used for estimating the performance of a positioning algorithm. In the second part of this paper, we exploit this property in developing a distributed algorithm, where the global positioning problem is solved suboptimally, using a divide-and-conquer approach of low complexity. The performance of this suboptimal algorithm is evaluated through computer simulation, and compared to previously published algorithms.

  20. An X-ray beam position monitor based on the photoluminescence of helium gas

    Science.gov (United States)

    Revesz, Peter; White, Jeffrey A.

    2005-03-01

    A new method for white beam position monitoring for both bend magnet and wiggler synchrotron X-ray radiation has been developed. This method utilizes visible light luminescence generated as a result of ionization by the intense X-ray flux. In video beam position monitors (VBPMs), the luminescence of helium gas at atmospheric pressure is observed through a view port using a CCD camera next to the beam line. The beam position, profile, integrated intensity and FWHM are calculated from the distribution of luminescence intensity in each captured image by custom software. Misalignment of upstream apertures changes the image profile making VBPMs helpful for initial alignment of upstream beam line components. VBPMs can thus provide more information about the X-ray beam than most beam position monitors (BPMs). A beam position calibration procedure, employing a tilted plane-parallel glass plate placed in front of the camera lens, has also been developed. The accuracy of the VBPM system was measured during a bench-top experiment to be better than 1 μm. The He-luminescence-based VBPM system has been operative on three CHESS beam lines (F hard-bend and wiggler, A-line wiggler and G-line wiggler) for about a year. The beam positions are converted to analog voltages and used as feedback signals for beam stabilization. In our paper we discuss details of VBPM construction and describe further results of its performance.

  1. Understanding positional cues in salamander limb regeneration: implications for optimizing cell-based regenerative therapies

    Directory of Open Access Journals (Sweden)

    Catherine D. McCusker

    2014-06-01

    Full Text Available Regenerative medicine has reached the point where we are performing clinical trials with stem-cell-derived cell populations in an effort to treat numerous human pathologies. However, many of these efforts have been challenged by the inability of the engrafted populations to properly integrate into the host environment to make a functional biological unit. It is apparent that we must understand the basic biology of tissue integration in order to apply these principles to the development of regenerative therapies in humans. Studying tissue integration in model organisms, where the process of integration between the newly regenerated tissues and the ‘old’ existing structures can be observed and manipulated, can provide valuable insights. Embryonic and adult cells have a memory of their original position, and this positional information can modify surrounding tissues and drive the formation of new structures. In this Review, we discuss the positional interactions that control the ability of grafted cells to integrate into existing tissues during the process of salamander limb regeneration, and discuss how these insights could explain the integration defects observed in current cell-based regenerative therapies. Additionally, we describe potential molecular tools that can be used to manipulate the positional information in grafted cell populations, and to promote the communication of positional cues in the host environment to facilitate the integration of engrafted cells. Lastly, we explain how studying positional information in current cell-based therapies and in regenerating limbs could provide key insights to improve the integration of cell-based regenerative therapies in the future.

  2. The First Result of Relative Positioning and Velocity Estimation Based on CAPS

    Science.gov (United States)

    Zhao, Jiaojiao; Ge, Jian; Wang, Liang; Wang, Ningbo; Zhou, Kai; Yuan, Hong

    2018-01-01

    The Chinese Area Positioning System (CAPS) is a new positioning system developed by the Chinese Academy of Sciences based on the communication satellites in geosynchronous orbit. The CAPS has been regarded as a pilot system to test the new technology for the design, construction and update of the BeiDou Navigation Satellite System (BDS). The system structure of CAPS, including the space, ground control station and user segments, is almost like the traditional Global Navigation Satellite Systems (GNSSs), but with the clock on the ground, the navigation signal in C waveband, and different principles of operation. The major difference is that the CAPS navigation signal is first generated at the ground control station, before being transmitted to the satellite in orbit and finally forwarded by the communication satellite transponder to the user. This design moves the clock from the satellite in orbit to the ground. The clock error can therefore be easily controlled and mitigated to improve the positioning accuracy. This paper will present the performance of CAPS-based relative positioning and velocity estimation as assessed in Beijing, China. The numerical results show that, (1) the accuracies of relative positioning, using only code measurements, are 1.25 and 1.8 m in the horizontal and vertical components, respectively; (2) meanwhile, they are about 2.83 and 3.15 cm in static mode and 6.31 and 10.78 cm in kinematic mode, respectively, when using the carrier-phase measurements with ambiguities fixed; and (3) the accuracy of the velocity estimation is about 0.04 and 0.11 m/s in static and kinematic modes, respectively. These results indicate the potential application of CAPS for high-precision positioning and velocity estimation and the availability of a new navigation mode based on communication satellites. PMID:29757204

  3. New paradigms in the repair of oxidative damage in human genome: mechanisms ensuring repair of mutagenic base lesions during replication and involvement of accessory proteins.

    Science.gov (United States)

    Dutta, Arijit; Yang, Chunying; Sengupta, Shiladitya; Mitra, Sankar; Hegde, Muralidhar L

    2015-05-01

    Oxidized bases in the mammalian genome, which are invariably mutagenic due to their mispairing property, are continuously induced by endogenous reactive oxygen species and more abundantly after oxidative stress. Unlike bulky base adducts induced by UV and other environmental mutagens in the genome that block replicative DNA polymerases, oxidatively damaged bases such as 5-hydroxyuracil, produced by oxidative deamination of cytosine in the template strand, do not block replicative polymerases and thus need to be repaired prior to replication to prevent mutation. Following up our earlier studies, which showed that the Nei endonuclease VIII like 1 (NEIL1) DNA glycosylase, one of the five base excision repair (BER)-initiating enzymes in mammalian cells, has enhanced expression during the S-phase and higher affinity for replication fork-mimicking single-stranded (ss) DNA substrates, we recently provided direct experimental evidence for NEIL1's role in replicating template strand repair. The key requirement for this event, which we named as the 'cow-catcher' mechanism of pre-replicative BER, is NEIL1's non-productive binding (substrate binding without product formation) to the lesion base in ss DNA template to stall DNA synthesis, causing fork regression. Repair of the lesion in reannealed duplex is then carried out by NEIL1 in association with the DNA replication proteins. NEIL1 (and other BER-initiating enzymes) also interact with several accessory and non-canonical proteins including the heterogeneous nuclear ribonucleoprotein U and Y-box-binding protein 1 as well as high mobility group box 1 protein, whose precise roles in BER are still obscure. In this review, we have discussed the recent advances in our understanding of oxidative genome damage repair pathways with particular focus on the pre-replicative template strand repair and the role of scaffold factors like X-ray repairs cross-complementing protein 1 and poly (ADP-ribose) polymerase 1 and other accessory

  4. Cultural bases for self-evaluation: seeing oneself positively in different cultural contexts.

    Science.gov (United States)

    Becker, Maja; Vignoles, Vivian L; Owe, Ellinor; Easterbrook, Matthew J; Brown, Rupert; Smith, Peter B; Bond, Michael Harris; Regalia, Camillo; Manzi, Claudia; Brambilla, Maria; Aldhafri, Said; González, Roberto; Carrasco, Diego; Paz Cadena, Maria; Lay, Siugmin; Schweiger Gallo, Inge; Torres, Ana; Camino, Leoncio; Özgen, Emre; Güner, Ülkü E; Yamakoğlu, Nil; Silveira Lemos, Flávia Cristina; Trujillo, Elvia Vargas; Balanta, Paola; Macapagal, Ma Elizabeth J; Cristina Ferreira, M; Herman, Ginette; de Sauvage, Isabelle; Bourguignon, David; Wang, Qian; Fülöp, Márta; Harb, Charles; Chybicka, Aneta; Mekonnen, Kassahun Habtamu; Martin, Mariana; Nizharadze, George; Gavreliuc, Alin; Buitendach, Johanna; Valk, Aune; Koller, Silvia H

    2014-05-01

    Several theories propose that self-esteem, or positive self-regard, results from fulfilling the value priorities of one's surrounding culture. Yet, surprisingly little evidence exists for this assertion, and theories differ about whether individuals must personally endorse the value priorities involved. We compared the influence of four bases for self-evaluation (controlling one's life, doing one's duty, benefitting others, achieving social status) among 4,852 adolescents across 20 cultural samples, using an implicit, within-person measurement technique to avoid cultural response biases. Cross-sectional and longitudinal analyses showed that participants generally derived feelings of self-esteem from all four bases, but especially from those that were most consistent with the value priorities of others in their cultural context. Multilevel analyses confirmed that the bases of positive self-regard are sustained collectively: They are predictably moderated by culturally normative values but show little systematic variation with personally endorsed values.

  5. Random Forest Based Coarse Locating and KPCA Feature Extraction for Indoor Positioning System

    Directory of Open Access Journals (Sweden)

    Yun Mo

    2014-01-01

    Full Text Available With the fast developing of mobile terminals, positioning techniques based on fingerprinting method draw attention from many researchers even world famous companies. To conquer some shortcomings of the existing fingerprinting systems and further improve the system performance, on the one hand, in the paper, we propose a coarse positioning method based on random forest, which is able to customize several subregions, and classify test point to the region with an outstanding accuracy compared with some typical clustering algorithms. On the other hand, through the mathematical analysis in engineering, the proposed kernel principal component analysis algorithm is applied for radio map processing, which may provide better robustness and adaptability compared with linear feature extraction methods and manifold learning technique. We build both theoretical model and real environment for verifying the feasibility and reliability. The experimental results show that the proposed indoor positioning system could achieve 99% coarse locating accuracy and enhance 15% fine positioning accuracy on average in a strong noisy environment compared with some typical fingerprinting based methods.

  6. A Foot-Mounted Inertial Measurement Unit (IMU) Positioning Algorithm Based on Magnetic Constraint.

    Science.gov (United States)

    Wang, Yan; Li, Xin; Zou, Jiaheng

    2018-03-01

    With the development of related applications, indoor positioning techniques have been more and more widely developed. Based on Wi-Fi, Bluetooth low energy (BLE) and geomagnetism, indoor positioning techniques often rely on the physical location of fingerprint information. The focus and difficulty of establishing the fingerprint database are in obtaining a relatively accurate physical location with as little given information as possible. This paper presents a foot-mounted inertial measurement unit (IMU) positioning algorithm under the loop closure constraint based on magnetic information. It can provide relatively reliable position information without maps and geomagnetic information and provides a relatively accurate coordinate for the collection of a fingerprint database. In the experiment, the features extracted by the multi-level Fourier transform method proposed in this paper are validated and the validity of loop closure matching is tested with a RANSAC-based method. Moreover, the loop closure detection results show that the cumulative error of the trajectory processed by the graph optimization algorithm is significantly suppressed, presenting a good accuracy. The average error of the trajectory under loop closure constraint is controlled below 2.15 m.

  7. A Foot-Mounted Inertial Measurement Unit (IMU Positioning Algorithm Based on Magnetic Constraint

    Directory of Open Access Journals (Sweden)

    Yan Wang

    2018-03-01

    Full Text Available With the development of related applications, indoor positioning techniques have been more and more widely developed. Based on Wi-Fi, Bluetooth low energy (BLE and geomagnetism, indoor positioning techniques often rely on the physical location of fingerprint information. The focus and difficulty of establishing the fingerprint database are in obtaining a relatively accurate physical location with as little given information as possible. This paper presents a foot-mounted inertial measurement unit (IMU positioning algorithm under the loop closure constraint based on magnetic information. It can provide relatively reliable position information without maps and geomagnetic information and provides a relatively accurate coordinate for the collection of a fingerprint database. In the experiment, the features extracted by the multi-level Fourier transform method proposed in this paper are validated and the validity of loop closure matching is tested with a RANSAC-based method. Moreover, the loop closure detection results show that the cumulative error of the trajectory processed by the graph optimization algorithm is significantly suppressed, presenting a good accuracy. The average error of the trajectory under loop closure constraint is controlled below 2.15 m.

  8. Gender-Based Differences in Outcomes After Orbital Atherectomy for the Treatment of De Novo Severely Calcified Coronary Lesions.

    Science.gov (United States)

    Lee, Michael S; Shlofmitz, Evan; Mansourian, Pejman; Sethi, Sanjum; Shlofmitz, Richard A

    2016-11-01

    We evaluated the relationship between gender and angiographic and clinical outcomes in patients with severely calcified lesions who underwent orbital atherectomy. Female gender is associated with increased risk of adverse clinical events after percutaneous coronary intervention (PCI). Severe coronary artery calcification increases the complexity of PCI and increases the risk of adverse cardiac events. Orbital atherectomy is effective in plaque modification, which facilitates stent delivery and expansion. Whether gender differences exist after orbital atherectomy is unclear. Our analysis retrospectively analyzed 458 consecutive real-world patients (314 males and 144 females) from three centers who underwent orbital atherectomy. The primary endpoint was the major adverse cardiac and cerebrovascular event (MACCE) rate, defined as the composite of death, myocardial infarction (MI), target-vessel revascularization (TVR), and stroke, at 30 days. The primary endpoint of MACCE was low and similar in females and males (0.7% vs 2.9%; P=.14). The individual endpoints of death (0.7% vs 1.6%; P=.43), MI (0.7% vs 1.3%; P=.58), TVR (0% vs 0%; P>.99), and stroke (0% vs 0.3%; P=.50) were low in both groups and did not differ. Angiographic complications were low: perforation (0.8% vs 0.7%; P>.90), dissection (0.8% vs 1.1%; P=.80), and no-reflow (0.8% vs 0.7%; P>.90). Plaque modification with orbital atherectomy was safe and provided similar angiographic and clinical outcomes between females and males. Randomized trials with longer-term follow-up are needed to support our results.

  9. Periodontal bone lesions

    International Nuclear Information System (INIS)

    Linden, L.W.J. van der.

    1985-01-01

    In the course of life the periodontum is subject to changes which may be physiological or pathological. Intraoral radiographs give insight into the hard structures of the dentomaxillar region and provides information on lesions in the bone of the periodontum in that they show radiopacities and radiolucencies caused by such lesions. In this thesis the relation is investigated between the true shape and dimensions of periodontal bone lesions and their radiographic images. A method is developed and tested of making standardized and reproducible radiographs suitable for longitudinal studies of periodontal lesions. Also the possibility is demonstrated of an objective and reproducible interpretation of radiographic characteristics of periodontal bone lesions. (Auth.)

  10. Performance of a video-image-subtraction-based patient positioning system

    International Nuclear Information System (INIS)

    Milliken, Barrett D.; Rubin, Steven J.; Hamilton, Russell J.; Johnson, L. Scott; Chen, George T.Y.

    1997-01-01

    Purpose: We have developed and tested an interactive video system that utilizes image subtraction techniques to enable high precision patient repositioning using surface features. We report quantitative measurements of system performance characteristics. Methods and Materials: Video images can provide a high precision, low cost measure of patient position. Image subtraction techniques enable one to incorporate detailed information contained in the image of a carefully verified reference position into real-time images. We have developed a system using video cameras providing orthogonal images of the treatment setup. The images are acquired, processed and viewed using an inexpensive frame grabber and a PC. The subtraction images provide the interactive guidance needed to quickly and accurately place a patient in the same position for each treatment session. We describe the design and implementation of our system, and its quantitative performance, using images both to measure changes in position, and to achieve accurate setup reproducibility. Results: Under clinical conditions (60 cm field of view, 3.6 m object distance), the position of static, high contrast objects could be measured with a resolution of 0.04 mm (rms) in each of two dimensions. The two-dimensional position could be reproduced using the real-time image display with a resolution of 0.15 mm (rms). Two-dimensional measurement resolution of the head of a patient undergoing treatment for head and neck cancer was 0.1 mm (rms), using a lateral view, measuring the variation in position of the nose and the ear over the course of a single radiation treatment. Three-dimensional repositioning accuracy of the head of a healthy volunteer using orthogonal camera views was less than 0.7 mm (systematic error) with an rms variation of 1.2 mm. Setup adjustments based on the video images were typically performed within a few minutes. The higher precision achieved using the system to measure objects than to reposition

  11. Therapeutic and lesional aspects of feline infectious peritonitis

    Directory of Open Access Journals (Sweden)

    Adrian C. Stancu

    2013-05-01

    Full Text Available The prevalence of feline infectious peritonitis (FIP can not be assessed on the basis of serological surveys because positive serological reagents rate does not correlate with disease rates. In units with more cats and numerous movements (input - output, the proportion of positive serological reagents is very high, and could reach, in some countries or regions at 50-75-100%, while among cats scattered nearhomes reactants rate positive to VPIF is well below 50%. Research conducted aimed at treating and determining evolutionary form of FIP based on pathological lesions in dead cats.

  12. Complex cystic lesions of the breast on ultrasonography: Feature analysis and BI-RADS assessment

    International Nuclear Information System (INIS)

    Hsu, Hsian-He; Yu, Jyh-Cherng; Lee, Herng-Sheng; Lin, Wen-Chiung; Chang, Wei-Chou; Tung, Ho-Jui; Huang, Guo-Shu; Hsu, Giu-Cheng

    2011-01-01

    Purpose: To analyze the features of breast complex cystic lesions at ultrasonography (US) and to determine appropriate Breast Imaging Reporting and Data System (BI-RADS) categories and management recommendations for these lesions based on US findings with pathologic correlation. Materials and methods: From July 2001 to June 2007, 152 consecutive pathologically proven complex cystic lesions on US were retrospectively reviewed. All lesions at US were evaluated for size, lesion characteristics, margins, and presence of abnormal axillary nodes. US features of lesions were classified into four types, and positive predictive values (PPVs) were calculated for each type. Clinical, imaging, and histopathological findings were reviewed. Results: Of the 152 lesions based on US appearance, 36 (24%) were classified as type I, 49 (32%) as type II, 28 (18%) as type III, and 39 (26%) as type IV. The PPVs for malignancy in each type were 14% for type I, 16% for type II, 14% for type III, and 41% for type IV. There was a significantly higher frequency of malignancy among lesions of type IV compared with the other three types (16/39 = 41% vs 5/36 = 14%, p = 0.0089; 16/39 = 41% vs 8/49 = 16%, p = 0.0098; and 16/39 = 41% vs 4/28 = 14%, p = 0.018 [Chi-squared test]). Lesions with maximum diameter equal to or larger than 20 mm, not circumscribed margins, or a mammographic finding of suspected malignancy had a high probability of malignancy (p < 0.05 for each). Conclusion: US is useful in evaluating the complex cystic lesions and in clarifying the indication for biopsy of these lesions. The four types of US classifications used in our study establish accepted benchmarks for these breast abnormalities when stratified according to BI-RADS categories.

  13. Complex cystic lesions of the breast on ultrasonography: Feature analysis and BI-RADS assessment

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Hsian-He, E-mail: hsianhe@yahoo.com.tw [Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Yu, Jyh-Cherng [Department of Surgery, Division of General Surgery, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Lee, Herng-Sheng [Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Lin, Wen-Chiung; Chang, Wei-Chou [Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China); Tung, Ho-Jui [Department of Healthcare Administration, Asia University, Taiwan (China); Huang, Guo-Shu; Hsu, Giu-Cheng [Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taiwan (China)

    2011-07-15

    Purpose: To analyze the features of breast complex cystic lesions at ultrasonography (US) and to determine appropriate Breast Imaging Reporting and Data System (BI-RADS) categories and management recommendations for these lesions based on US findings with pathologic correlation. Materials and methods: From July 2001 to June 2007, 152 consecutive pathologically proven complex cystic lesions on US were retrospectively reviewed. All lesions at US were evaluated for size, lesion characteristics, margins, and presence of abnormal axillary nodes. US features of lesions were classified into four types, and positive predictive values (PPVs) were calculated for each type. Clinical, imaging, and histopathological findings were reviewed. Results: Of the 152 lesions based on US appearance, 36 (24%) were classified as type I, 49 (32%) as type II, 28 (18%) as type III, and 39 (26%) as type IV. The PPVs for malignancy in each type were 14% for type I, 16% for type II, 14% for type III, and 41% for type IV. There was a significantly higher frequency of malignancy among lesions of type IV compared with the other three types (16/39 = 41% vs 5/36 = 14%, p = 0.0089; 16/39 = 41% vs 8/49 = 16%, p = 0.0098; and 16/39 = 41% vs 4/28 = 14%, p = 0.018 [Chi-squared test]). Lesions with maximum diameter equal to or larger than 20 mm, not circumscribed margins, or a mammographic finding of suspected malignancy had a high probability of malignancy (p < 0.05 for each). Conclusion: US is useful in evaluating the complex cystic lesions and in clarifying the indication for biopsy of these lesions. The four types of US classifications used in our study establish accepted benchmarks for these breast abnormalities when stratified according to BI-RADS categories.

  14. Hybrid organic/inorganic position-sensitive detectors based on PEDOT:PSS/n-Si

    Science.gov (United States)

    Javadi, Mohammad; Gholami, Mahdiyeh; Torbatiyan, Hadis; Abdi, Yaser

    2018-03-01

    Various configurations like p-n junctions, metal-semiconductor Schottky barriers, and metal-oxide-semiconductor structures have been widely used in position-sensitive detectors. In this report, we propose a PEDOT:PSS/n-Si heterojunction as a hybrid organic/inorganic configuration for position-sensitive detectors. The influence of the thickness of the PEDOT:PSS layer, the wavelength of incident light, and the intensity of illumination on the device performance are investigated. The hybrid PSD exhibits very high sensitivity (>100 mV/mm), excellent nonlinearity (0.995) with a response time of heterojunction are very promising for developing a new class of position-sensitive detectors based on the hybrid organic/inorganic junctions.

  15. Protection algorithm for a wind turbine generator based on positive- and negative-sequence fault components

    DEFF Research Database (Denmark)

    Zheng, Tai-Ying; Cha, Seung-Tae; Crossley, Peter A.

    2011-01-01

    A protection relay for a wind turbine generator (WTG) based on positive- and negative-sequence fault components is proposed in the paper. The relay uses the magnitude of the positive-sequence component in the fault current to detect a fault on a parallel WTG, connected to the same power collection...... feeder, or a fault on an adjacent feeder; but for these faults, the relay remains stable and inoperative. A fault on the power collection feeder or a fault on the collection bus, both of which require an instantaneous tripping response, are distinguished from an inter-tie fault or a grid fault, which...... in the fault current is used to decide on either instantaneous or delayed operation. The operating performance of the relay is then verified using various fault scenarios modelled using EMTP-RV. The scenarios involve changes in the position and type of fault, and the faulted phases. Results confirm...

  16. The spectral positioning algorithm of new spectrum vehicle based on convex programming in wireless sensor network

    Science.gov (United States)

    Zhang, Yongjun; Lu, Zhixin

    2017-10-01

    Spectrum resources are very precious, so it is increasingly important to locate interference signals rapidly. Convex programming algorithms in wireless sensor networks are often used as localization algorithms. But in view of the traditional convex programming algorithm is too much overlap of wireless sensor nodes that bring low positioning accuracy, the paper proposed a new algorithm. Which is mainly based on the traditional convex programming algorithm, the spectrum car sends unmanned aerial vehicles (uses) that can be used to record data periodically along different trajectories. According to the probability density distribution, the positioning area is segmented to further reduce the location area. Because the algorithm only increases the communication process of the power value of the unknown node and the sensor node, the advantages of the convex programming algorithm are basically preserved to realize the simple and real-time performance. The experimental results show that the improved algorithm has a better positioning accuracy than the original convex programming algorithm.

  17. Embodied positioning/discourse analysis of a research based leadership development forum

    DEFF Research Database (Denmark)

    Bager, Ann

    2018-01-01

    The present article engages a discourse analysis of identity work as it is accomplished in a research and dialogue based leadership development forum in a university setting. It displays how different interactional setups in a positioning exercise prompt diverse spaces of possibilities that shape...... the identity work in situ. Through a micro-generic positioning analysis of the participants’ small story efforts (M. Bamberg, 2006; M. Bamberg & Georgakopoulou, 2008) combined with an analysis of dialogicality and other-orientation (Bakhtin, 1986; Linell, 2009) it is shown how counter and complicit discourses...... as a natural positive phenomenon with attached emancipating consequences. It aspires to emphasize both the boarder (D) and the local (d) dimensions of discourse, which is increasingly pursued and recommended within the field of interaction, dialogue and discourse studies. (Bager, 2013; Bager et al...

  18. Positive Orientation-a Common Base for Hedonistic and Eudemonistic Happiness?

    Science.gov (United States)

    Oleś, Piotr; Jankowski, Tomasz

    2018-01-01

    Positive orientation (PO) is proposed as a common base for hedonistic and eudemonistic senses of happiness. PO involves a tendency to formulate positive judgments concerning the self, one's personal life, and the future. Previously, PO had been investigated in the context of the hedonistic approach to well-being. In this article, we tested a broader understanding of PO, which is conceptualized, here, as a latent factor underlying variables that exemplify hedonistic and eudemonistic view on happiness. Using two samples ( N  = 159 and N  = 200), we tested three models of PO extended to include various measures of meaning of life. The extended models fitted the data well. Results suggest that PO can be a general factor that is the basis for integrating two aspects of well-being: searching for positivity and pleasure, as well as striving for meaning.

  19. An ILP based memetic algorithm for finding minimum positive influence dominating sets in social networks

    Science.gov (United States)

    Lin, Geng; Guan, Jian; Feng, Huibin

    2018-06-01

    The positive influence dominating set problem is a variant of the minimum dominating set problem, and has lots of applications in social networks. It is NP-hard, and receives more and more attention. Various methods have been proposed to solve the positive influence dominating set problem. However, most of the existing work focused on greedy algorithms, and the solution quality needs to be improved. In this paper, we formulate the minimum positive influence dominating set problem as an integer linear programming (ILP), and propose an ILP based memetic algorithm (ILPMA) for solving the problem. The ILPMA integrates a greedy randomized adaptive construction procedure, a crossover operator, a repair operator, and a tabu search procedure. The performance of ILPMA is validated on nine real-world social networks with nodes up to 36,692. The results show that ILPMA significantly improves the solution quality, and is robust.

  20. Design and Implementation of Browser based GPS/GPRS Vehicle Positioning and Tracking System

    Directory of Open Access Journals (Sweden)

    Zhang Keqiang

    2015-01-01

    Full Text Available This paper mainly describes a vehicle positioning and tracking system which is based on browser, GPS and GPRS. And this system takes advantage of Baidu Map as basic material to show vehicle status, which enables drivers and supervisor to monitor the vehicle’s current and past positions. The vehicle’s location data is got from satellites, and these data is sent to the central server through GPRS, the central server will store formatted data into the database after the data is parsed; Later, these data stored in the database will be used by web application and displayed on the map as markers. This paper also involves the implementation on mobile side, and this system used Baidu map JavaScript interface, Ajax, JSP and JSON to implement the vehicle positioning and tracking system.

  1. Distributed Position-Based Consensus of Second-Order Multiagent Systems With Continuous/Intermittent Communication.

    Science.gov (United States)

    Song, Qiang; Liu, Fang; Wen, Guanghui; Cao, Jinde; Yang, Xinsong

    2017-04-24

    This paper considers the position-based consensus in a network of agents with double-integrator dynamics and directed topology. Two types of distributed observer algorithms are proposed to solve the consensus problem by utilizing continuous and intermittent position measurements, respectively, where each observer does not interact with any other observers. For the case of continuous communication between network agents, some convergence conditions are derived for reaching consensus in the network with a single constant delay or multiple time-varying delays on the basis of the eigenvalue analysis and the descriptor method. When the network agents can only obtain intermittent position data from local neighbors at discrete time instants, the consensus in the network without time delay or with nonuniform delays is investigated by using the Wirtinger's inequality and the delayed-input approach. Numerical examples are given to illustrate the theoretical analysis.

  2. Flocking in Multi-Agent Systems with Multiple Virtual Leaders Based Only on Position Measurements

    International Nuclear Information System (INIS)

    Su Housheng

    2012-01-01

    Most existing flocking algorithms assume one single virtual leader and rely on information on both relative positions and relative velocities among neighboring agents. In this paper, the problem of controlling a flock of mobile autonomous agents to follow multiple virtual leaders is investigated by using only position information in the sense that agents with the same virtual leader asymptotically attain the same velocity and track the corresponding virtual leader based on only position measurements. A flocking algorithm is proposed under which every agent asymptotically attains its desired velocity, collision between agents can be avoided, and the final tight formation minimizes all agents' global potentials. A simulation example is presented to verify and illustrate the theoretical results. (general)

  3. A Model of Market Positioning of Destinations Based on Online Customer Reviews of Lodgings

    Directory of Open Access Journals (Sweden)

    Manuel Rodríguez-Díaz

    2017-12-01

    Full Text Available The aim of this study is to develop a methodology to determine the competitive online positioning of lodging companies in different tourist destinations. The rise of the digital age has allowed many customers to share their opinions through specialized websites, providing a dynamic and constantly updated evaluation of the market. In this context, competitiveness is an essential factor in the economic sustainability of destinations. The competitive positioning of destinations is determined by the scale of variables used by Booking.com. The price and lodging category variables are also used, as well as three new variables derived from the initial scale: the quality average, value and added value. This methodology provides a tool to determine the level of competitiveness of the lodging offered in tourist destinations, based on which, actions can be taken to improve destinations’ positioning.

  4. Developing and implementing a positive behavioral reinforcement intervention in prison-based drug treatment: Project BRITE.

    Science.gov (United States)

    Burdon, William M; St De Lore, Jef; Prendergast, Michael L

    2011-09-01

    Within prison settings, the reliance on punishment for controlling inappropriate or noncompliant behavior is self-evident. What is not so evident is the similarity between this reliance on punishment and the use of positive reinforcements to increase desired behaviors. However, seldom do inmates receive positive reinforcement for engaging in prosocial behaviors or, for inmates receiving drug treatment, behaviors that are consistent with or support their recovery. This study provides an overview of the development and implementation of a positive behavioral reinforcement intervention in male and female prison-based drug treatment programs. The active involvement of institutional staff, treatment staff, and inmates enrolled in the treatment programs in the development of the intervention along with the successful branding of the intervention were effective at promoting support and participation. However, these factors may also have ultimately impacted the ability of the randomized design to reliably demonstrate the effectiveness of the intervention.

  5. RELATIVE PANORAMIC CAMERA POSITION ESTIMATION FOR IMAGE-BASED VIRTUAL REALITY NETWORKS IN INDOOR ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    M. Nakagawa

    2017-09-01

    Full Text Available Image-based virtual reality (VR is a virtual space generated with panoramic images projected onto a primitive model. In imagebased VR, realistic VR scenes can be generated with lower rendering cost, and network data can be described as relationships among VR scenes. The camera network data are generated manually or by an automated procedure using camera position and rotation data. When panoramic images are acquired in indoor environments, network data should be generated without Global Navigation Satellite Systems (GNSS positioning data. Thus, we focused on image-based VR generation using a panoramic camera in indoor environments. We propose a methodology to automate network data generation using panoramic images for an image-based VR space. We verified and evaluated our methodology through five experiments in indoor environments, including a corridor, elevator hall, room, and stairs. We confirmed that our methodology can automatically reconstruct network data using panoramic images for image-based VR in indoor environments without GNSS position data.

  6. Automated Breast Ultrasound Lesions Detection using Convolutional Neural Networks.

    Science.gov (United States)

    Yap, Moi Hoon; Pons, Gerard; Marti, Joan; Ganau, Sergi; Sentis, Melcior; Zwiggelaar, Reyer; Davison, Adrian K; Marti, Robert

    2017-08-07

    Breast lesion detection using ultrasound imaging is considered an important step of Computer-Aided Diagnosis systems. Over the past decade, researchers have demonstrated the possibilities to automate the initial lesion detection. However, the lack of a common dataset impedes research when comparing the performance of such algorithms. This paper proposes the use of deep learning approaches for breast ultrasound lesion detection and investigates three different methods: a Patch-based LeNet, a U-Net, and a transfer learning approach with a pretrained FCN-AlexNet. Their performance is compared against four state-of-the-art lesion detection algorithms (i.e. Radial Gradient Index, Multifractal Filtering, Rule-based Region Ranking and Deformable Part Models). In addition, this paper compares and contrasts two conventional ultrasound image datasets acquired from two different ultrasound systems. Dataset A comprises 306 (60 malignant and 246 benign) images and Dataset B comprises 163 (53 malignant and 110 benign) images. To overcome the lack of public datasets in this domain, Dataset B will be made available for research purposes. The results demonstrate an overall improvement by the deep learning approaches when assessed on both datasets in terms of True Positive Fraction, False Positives per image, and F-measure.

  7. Self-positioned thin Pb-alloy base electrode Josephson junction

    International Nuclear Information System (INIS)

    Kuroda, K.; Sato, K.

    1986-01-01

    A self-positioned thin (SPOT) Pb-alloy base electrode Josephson junction is developed. In this junction, a 50-nm thick Pb-alloy base electrode is restricted within the junction region on an Nb underlayer using a self-alignment technique. The grain size reduction and the base electrode area restriction greatly improve thermal cycling stability, where the thermal cycling tests of 4000 proposed junctions (5 x 5 μm 2 ) showed no failures after 4000 cycles. In addition, the elimination of insulator layer stress on the Pb-alloy base electrode rectifies the problem of size effect on current density. The Nb underlayers also serve to isolate the Pb-alloy base electrodes from the resistors

  8. Improvement of Gaofen-3 Absolute Positioning Accuracy Based on Cross-Calibration

    Directory of Open Access Journals (Sweden)

    Mingjun Deng

    2017-12-01

    Full Text Available The Chinese Gaofen-3 (GF-3 mission was launched in August 2016, equipped with a full polarimetric synthetic aperture radar (SAR sensor in the C-band, with a resolution of up to 1 m. The absolute positioning accuracy of GF-3 is of great importance, and in-orbit geometric calibration is a key technology for improving absolute positioning accuracy. Conventional geometric calibration is used to accurately calibrate the geometric calibration parameters of the image (internal delay and azimuth shifts using high-precision ground control data, which are highly dependent on the control data of the calibration field, but it remains costly and labor-intensive to monitor changes in GF-3’s geometric calibration parameters. Based on the positioning consistency constraint of the conjugate points, this study presents a geometric cross-calibration method for the rapid and accurate calibration of GF-3. The proposed method can accurately calibrate geometric calibration parameters without using corner reflectors and high-precision digital elevation models, thus improving absolute positioning accuracy of the GF-3 image. GF-3 images from multiple regions were collected to verify the absolute positioning accuracy after cross-calibration. The results show that this method can achieve a calibration accuracy as high as that achieved by the conventional field calibration method.

  9. Research on position and orientation measurement method for roadheader based on vision/INS

    Science.gov (United States)

    Yang, Jinyong; Zhang, Guanqin; Huang, Zhe; Ye, Yaozhong; Ma, Bowen; Wang, Yizhong

    2018-01-01

    Roadheader which is a kind of special equipment for large tunnel excavation has been widely used in Coal Mine. It is one of the main mechanical-electrical equipment for mine production and also has been regarded as the core equipment for underground tunnel driving construction. With the deep application of the rapid driving system, underground tunnel driving methods with higher automation level are required. In this respect, the real-time position and orientation measurement technique for roadheader is one of the most important research contents. For solving the problem of position and orientation measurement automatically in real time for roadheaders, this paper analyses and compares the features of several existing measuring methods. Then a new method based on the combination of monocular vision and strap down inertial navigation system (SINS) would be proposed. By realizing five degree-of-freedom (DOF) measurement of real-time position and orientation of roadheader, this method has been verified by the rapid excavation equipment in Daliuta coal mine. Experiment results show that the accuracy of orientation measurement is better than 0.1°, the standard deviation of static drift is better than 0.25° and the accuracy of position measurement is better than 1cm. It is proved that this method can be used in real-time position and orientation measurement application for roadheader which has a broad prospect in coal mine engineering.

  10. An Optimal Design of Multiple Antenna Positions on Mobile Devices Based on Mutual Coupling Analysis

    Directory of Open Access Journals (Sweden)

    Peerapong Uthansakul

    2011-01-01

    Full Text Available The topic of practical implementation of multiple antenna systems for mobile communications has recently gained a lot of attention. Due to the area constraint on a mobile device, the problem of how to design such a system in order to achieve the best benefit is still a huge challenge. In this paper, genetic algorithm (GA is used to find the optimal antenna positions on a mobile device. Two cases of 3×3 and 4×4 MIMO systems are undertaken. The effect of mutual coupling based on Z-parameter is the main factor to determine the MIMO capacity concerning the objective function of GA search. The results confirm the success of the proposed method to design MIMO antenna positions on a mobile device. Moreover, this paper introduces the method to design the antenna positions for the condition of nondeterministic channel. The concern of channel variation has been included in the process of finding optimal MIMO antenna positions. The results suggest that the averaging position from all GA solutions according to all channel conditions provides the most acceptable benefit.

  11. Wideband Motion Control by Position and Acceleration Input Based Disturbance Observer

    Science.gov (United States)

    Irie, Kouhei; Katsura, Seiichiro; Ohishi, Kiyoshi

    The disturbance observer can observe and suppress the disturbance torque within its bandwidth. Recent motion systems begin to spread in the society and they are required to have ability to contact with unknown environment. Such a haptic motion requires much wider bandwidth. However, since the conventional disturbance observer attains the acceleration response by the second order derivative of position response, the bandwidth is limited due to the derivative noise. This paper proposes a novel structure of a disturbance observer. The proposed disturbance observer uses an acceleration sensor for enlargement of bandwidth. Generally, the bandwidth of an acceleration sensor is from 1Hz to more than 1kHz. To cover DC range, the conventional position sensor based disturbance observer is integrated. Thus, the performance of the proposed Position and Acceleration input based disturbance observer (PADO) is superior to the conventional one. The PADO is applied to position control (infinity stiffness) and force control (zero stiffness). The numerical and experimental results show viability of the proposed method.

  12. Research on key technology of yacht positioning based on binocular parallax

    Science.gov (United States)

    Wang, Wei; Wei, Ping; Liu, Zengzhi

    2016-10-01

    Yacht has become a fashionable way for entertainment. However, to obtain the precise location of a yacht docked at a port has become one of the concerns of a yacht manager. To deal with this issue, we adopt a positioning method based on the principle of binocular parallax and background difference in this paper. Binocular parallax uses cameras to get multi-dimensional perspective of the yacht based on geometric principle of imaging. In order to simplify the yacht localization problem, we install LED light indicator as the key point on a yacht. And let it flash at a certain frequency during day time and night time. After getting the distance between the LED and the cameras, locating the yacht is easy. Compared with other traditional positioning methods, this method is simpler and easier to implement. In this paper, we study the yacht positioning method using the LED indicator. Simulation experiment is done for a yacht model in the distance of 3 meters. The experimental result shows that our method is feasible and easy to implement with a small 15% positioning error.

  13. Hausdorff-Based RC and IESIL Combined Positioning Algorithm for Underwater Geomagnetic Navigation

    Directory of Open Access Journals (Sweden)

    Lin Yi

    2010-01-01

    Full Text Available This paper presents a primitive solution with novel scheme and algorithm for Underwater geoMagnetic Navigation (UMN, which now occurs as the hot-point in the research field of navigation. UMN as an independent or supplementary technique can theoretically supply accurate locations for marine vehicles, but in practice there are plenty of restrictions for UMN's application (e.g., geomagnetic daily variation. After analysis of the theoretical model of geomagnetic positioning in the correlation-matching mode from the viewpoint of pattern recognition, this paper proposed an appropriate matching scenario and a combined positioning algorithm for UMN. The subalgorithm of Hausdorff-based Relative Correlation (RC corresponding to the pattern classification module implements the coarse positioning, and the subalgorithm of Isograms Equidistance-Segmenting theIntersection Lines (IESILs associated with the module of feature extraction continues the fine positioning. The experiments based on the simulation platform and the real-surveyed data both validate the new algorithm, and its efficiency and accuracy are also discussed. It can be concluded that the work introduced in this paper gives an initial and real validation of UMN's potentiality.

  14. Precise positioning method for multi-process connecting based on binocular vision

    Science.gov (United States)

    Liu, Wei; Ding, Lichao; Zhao, Kai; Li, Xiao; Wang, Ling; Jia, Zhenyuan

    2016-01-01

    With the rapid development of aviation and aerospace, the demand for metal coating parts such as antenna reflector, eddy-current sensor and signal transmitter, etc. is more and more urgent. Such parts with varied feature dimensions, complex three-dimensional structures, and high geometric accuracy are generally fabricated by the combination of different manufacturing technology. However, it is difficult to ensure the machining precision because of the connection error between different processing methods. Therefore, a precise positioning method is proposed based on binocular micro stereo vision in this paper. Firstly, a novel and efficient camera calibration method for stereoscopic microscope is presented to solve the problems of narrow view field, small depth of focus and too many nonlinear distortions. Secondly, the extraction algorithms for law curve and free curve are given, and the spatial position relationship between the micro vision system and the machining system is determined accurately. Thirdly, a precise positioning system based on micro stereovision is set up and then embedded in a CNC machining experiment platform. Finally, the verification experiment of the positioning accuracy is conducted and the experimental results indicated that the average errors of the proposed method in the X and Y directions are 2.250 μm and 1.777 μm, respectively.

  15. Robust Adaptive Beamforming with Sensor Position Errors Using Weighted Subspace Fitting-Based Covariance Matrix Reconstruction.

    Science.gov (United States)

    Chen, Peng; Yang, Yixin; Wang, Yong; Ma, Yuanliang

    2018-05-08

    When sensor position errors exist, the performance of recently proposed interference-plus-noise covariance matrix (INCM)-based adaptive beamformers may be severely degraded. In this paper, we propose a weighted subspace fitting-based INCM reconstruction algorithm to overcome sensor displacement for linear arrays. By estimating the rough signal directions, we construct a novel possible mismatched steering vector (SV) set. We analyze the proximity of the signal subspace from the sample covariance matrix (SCM) and the space spanned by the possible mismatched SV set. After solving an iterative optimization problem, we reconstruct the INCM using the estimated sensor position errors. Then we estimate the SV of the desired signal by solving an optimization problem with the reconstructed INCM. The main advantage of the proposed algorithm is its robustness against SV mismatches dominated by unknown sensor position errors. Numerical examples show that even if the position errors are up to half of the assumed sensor spacing, the output signal-to-interference-plus-noise ratio is only reduced by 4 dB. Beam patterns plotted using experiment data show that the interference suppression capability of the proposed beamformer outperforms other tested beamformers.

  16. FFA STUDY OF MACULAR LESIONS

    Directory of Open Access Journals (Sweden)

    K. Vinayagamurthy

    2017-08-01

    Full Text Available BACKGROUND Macula is an important portion of retina that occupies the posterior pole of retina. Any disease that affects macula results in significant loss of central vision, form vision and colour vision to an extent. Macular lesions can be hereditary as well as acquired. Macular lesions occur in both younger and older individuals. Anatomically, a macular lesions can vary from a simple lesion like an RPF defect to a vision-threatening lesions like choroidal neovascular membrane. Many screening tests that are sensitive and specific are available to assess the functioning of macula called as ‘macular function test’. But, the greater understanding of the retinal vascular led to the usage of fluorescein angiogram in the detection and screening of macular, retinovascular and optic disc lesions. Through fundus fluorescein angiogram is a thirty-year-old procedure; it is still in vogue in almost all parts of the world. It has its own merits. The aim of the study is to study the role of fluorescein angiography in the evaluation of macular lesions. MATERIALS AND METHODS A hospital-based prospective randomised study was done, which included 50 patients. Detailed patient history was taken and thorough ocular and systemic examination was done. All patients were examined by ophthalmoscopy (direct and indirect and slit-lamp examination with 90D followed by fluorescein angiography. Ophthalmoscopic and fluorescein angiography findings were analysed and categorised. Patients were advised proper ocular and systemic treatment and follow up. RESULTS 50 cases with macular lesions were analysed and categorised into conditions like ARMD, CSR, macular oedema, CME, degenerations and dystrophies and miscellaneous conditions. FFA altered the diagnosis in 8% cases and categorised the cases in all cases. 16% patients developed adverse reactions like allergy, vomiting and nausea. On statistical analysis, FFA proved to be cheap and superior diagnostic tool in confirming

  17. Life review based on remembering specific positive events in active aging.

    Science.gov (United States)

    Latorre, José M; Serrano, Juan P; Ricarte, Jorge; Bonete, Beatriz; Ros, Laura; Sitges, Esther

    2015-02-01

    The aim of this study is to evaluate the effectiveness of life review (LR) based on specific positive events in non-depressed older adults taking part in an active aging program. Fifty-five older adults were randomly assigned to an experimental group or an active control (AC) group. A six-session individual training of LR based on specific positive events was carried out with the experimental group. The AC group undertook a "media workshop" of six sessions focused on learning journalistic techniques. Pre-test and post-test measures included life satisfaction, depressive symptoms, experiencing the environment as rewarding, and autobiographical memory (AM) scales. LR intervention decreased depressive symptomatology, improved life satisfaction, and increased specific memories. The findings suggest that practice in AM for specific events is an effective component of LR that could be a useful tool in enhancing emotional well-being in active aging programs, thus reducing depressive symptoms. © The Author(s) 2014.

  18. Insecurity of position-based quantum-cryptography protocols against entanglement attacks

    International Nuclear Information System (INIS)

    Lau, Hoi-Kwan; Lo, Hoi-Kwong

    2011-01-01

    Recently, position-based quantum cryptography has been claimed to be unconditionally secure. On the contrary, here we show that the existing proposals for position-based quantum cryptography are, in fact, insecure if entanglement is shared among two adversaries. Specifically, we demonstrate how the adversaries can incorporate ideas of quantum teleportation and quantum secret sharing to compromise the security with certainty. The common flaw to all current protocols is that the Pauli operators always map a codeword to a codeword (up to an irrelevant overall phase). We propose a modified scheme lacking this property in which the same cheating strategy used to undermine the previous protocols can succeed with a rate of at most 85%. We prove the modified protocol is secure when the shared quantum resource between the adversaries is a two- or three-level system.

  19. Robust and unobtrusive algorithm based on position independence for step detection

    Science.gov (United States)

    Qiu, KeCheng; Li, MengYang; Luo, YiHan

    2018-04-01

    Running is becoming one of the most popular exercises among the people, monitoring steps can help users better understand their running process and improve exercise efficiency. In this paper, we design and implement a robust and unobtrusive algorithm based on position independence for step detection under real environment. It applies Butterworth filter to suppress high frequency interference and then employs the projection based on mathematics to transform system to solve the problem of unknown position of smartphone. Finally, using sliding window to suppress the false peak. The algorithm was tested for eight participants on the Android 7.0 platform. In our experiments, the results show that the proposed algorithm can achieve desired effect in spite of device pose.

  20. A fully automatic, threshold-based segmentation method for the estimation of the Metabolic Tumor Volume from PET images: validation on 3D printed anthropomorphic oncological lesions

    Science.gov (United States)

    Gallivanone, F.; Interlenghi, M.; Canervari, C.; Castiglioni, I.

    2016-01-01

    18F-Fluorodeoxyglucose (18F-FDG) Positron Emission Tomography (PET) is a standard functional diagnostic technique to in vivo image cancer. Different quantitative paramters can be extracted from PET images and used as in vivo cancer biomarkers. Between PET biomarkers Metabolic Tumor Volume (MTV) has gained an important role in particular considering the development of patient-personalized radiotherapy treatment for non-homogeneous dose delivery. Different imaging processing methods have been developed to define MTV. The different proposed PET segmentation strategies were validated in ideal condition (e.g. in spherical objects with uniform radioactivity concentration), while the majority of cancer lesions doesn't fulfill these requirements. In this context, this work has a twofold objective: 1) to implement and optimize a fully automatic, threshold-based segmentation method for the estimation of MTV, feasible in clinical practice 2) to develop a strategy to obtain anthropomorphic phantoms, including non-spherical and non-uniform objects, miming realistic oncological patient conditions. The developed PET segmentation algorithm combines an automatic threshold-based algorithm for the definition of MTV and a k-means clustering algorithm for the estimation of the background. The method is based on parameters always available in clinical studies and was calibrated using NEMA IQ Phantom. Validation of the method was performed both in ideal (e.g. in spherical objects with uniform radioactivity concentration) and non-ideal (e.g. in non-spherical objects with a non-uniform radioactivity concentration) conditions. The strategy to obtain a phantom with synthetic realistic lesions (e.g. with irregular shape and a non-homogeneous uptake) consisted into the combined use of standard anthropomorphic phantoms commercially and irregular molds generated using 3D printer technology and filled with a radioactive chromatic alginate. The proposed segmentation algorithm was feasible in a

  1. Trans-zygomatic middle cranial fossa approach to access lesions around the cavernous sinus and anterior parahippocampus: a minimally invasive skull base approach.

    Science.gov (United States)

    Melamed, Itay; Tubbs, R Shane; Payner, Troy D; Cohen-Gadol, Aaron A

    2009-08-01

    Exposure of the cavernous sinus or anterior parahippocampus often involves a wide exposure of the temporal lobe and mobilization of the temporalis muscle associated with temporal lobe retraction. The authors present a cadaveric study to illustrate the feasibility, advantages and landmarks necessary to perform a trans-zygomatic middle fossa approach to lesions around the cavernous sinus and anterior parahippocampus. The authors performed bilateral trans-zygomatic middle fossae exposures to reach the cavernous sinus and parahippocampus in five cadavers (10 sides). We assessed the morbidity associated with this procedure and compared the indications, advantages, and disadvantages of this method versus more extensive skull base approaches. A vertical linear incision along the middle portion of the zygomatic arch was extended one finger breadth inferior to the inferior edge of the zygomatic arch. Careful dissection inferior to the arch allowed preservation of facial nerve branches. A zygomatic osteotomy was followed via a linear incision through the temporalis muscle and exposure of the middle cranial fossa floor. A craniotomy along the inferolateral temporal bone and middle fossa floor allowed extradural dissection along the middle fossa floor and exposure of the cavernous sinus including all three divisions of the trigeminal nerve. Intradural inspection demonstrated adequate exposure of the parahippocampus. Exposure of the latter required minimal or no retraction of the temporal lobe. The trans-zygomatic middle fossa approach is a simplified skull base exposure using a linear incision, which may avoid the invasivity of more extensive skull base approaches while providing an adequate corridor for resection of cavernous sinus and parahippocampus lesions. The advantages of this approach include its efficiency, ease, minimalism, preservation of the temporalis muscle, and minimal retraction of the temporal lobe.

  2. Benign Paroxysmal Positional Vertigo after Dental Procedures: A Population-Based Case-Control Study

    OpenAIRE

    Chang, Tzu-Pu; Lin, Yueh-Wen; Sung, Pi-Yu; Chuang, Hsun-Yang; Chung, Hsien-Yang; Liao, Wen-Ling

    2016-01-01

    Background Benign paroxysmal positional vertigo (BPPV), the most common type of vertigo in the general population, is thought to be caused by dislodgement of otoliths from otolithic organs into the semicircular canals. In most cases, however, the cause behind the otolith dislodgement is unknown. Dental procedures, one of the most common medical treatments, are considered to be a possible cause of BPPV, although this has yet to be proven. This study is the first nationwide population-based cas...

  3. Confirmational study: a positive-based thumb and finger sucking elimination program.

    Science.gov (United States)

    Green, Shari E

    2010-11-01

    This article emphasizes the critical need for information specifically regarding the topic of retained sucking behaviors. The study aimed to confirm results provided by Van Norman of 723 subjects in 1997. Parent surveys were collected on 441 subjects who received an orofacial myofunctional treatment program provided by one certified orofacial myologist. Results of this study do confirm that retained digit sucking behavior may be addressed successfully and expediently by a program based on positive behavior modification techniques.

  4. Binocular Vision-Based Position and Pose of Hand Detection and Tracking in Space

    Science.gov (United States)

    Jun, Chen; Wenjun, Hou; Qing, Sheng

    After the study of image segmentation, CamShift target tracking algorithm and stereo vision model of space, an improved algorithm based of Frames Difference and a new space point positioning model were proposed, a binocular visual motion tracking system was constructed to verify the improved algorithm and the new model. The problem of the spatial location and pose of the hand detection and tracking have been solved.

  5. An Indoor Positioning System Based on Wearables for Ambient-Assisted Living.

    Science.gov (United States)

    Belmonte-Fernández, Óscar; Puertas-Cabedo, Adrian; Torres-Sospedra, Joaquín; Montoliu-Colás, Raúl; Trilles-Oliver, Sergi

    2016-12-25

    The urban population is growing at such a rate that by 2050 it is estimated that 84% of the world's population will live in cities, with flats being the most common living place. Moreover, WiFi technology is present in most developed country urban areas, with a quick growth in developing countries. New Ambient-Assisted Living applications will be developed in the near future having user positioning as ground technology: elderly tele-care, energy consumption, security and the like are strongly based on indoor positioning information. We present an Indoor Positioning System for wearable devices based on WiFi fingerprinting. Smart-watch wearable devices are used to acquire the WiFi strength signals of the surrounding Wireless Access Points used to build an ensemble of Machine Learning classification algorithms. Once built, the ensemble algorithm is used to locate a user based on the WiFi strength signals provided by the wearable device. Experimental results for five different urban flats are reported, showing that the system is robust and reliable enough for locating a user at room level into his/her home. Another interesting characteristic of the presented system is that it does not require deployment of any infrastructure, and it is unobtrusive, the only device required for it to work is a smart-watch.

  6. An Indoor Positioning System Based on Wearables for Ambient-Assisted Living

    Directory of Open Access Journals (Sweden)

    Óscar Belmonte-Fernández

    2016-12-01

    Full Text Available The urban population is growing at such a rate that by 2050 it is estimated that 84% of the world’s population will live in cities, with flats being the most common living place. Moreover, WiFi technology is present in most developed country urban areas, with a quick growth in developing countries. New Ambient-Assisted Living applications will be developed in the near future having user positioning as ground technology: elderly tele-care, energy consumption, security and the like are strongly based on indoor positioning information. We present an Indoor Positioning System for wearable devices based on WiFi fingerprinting. Smart-watch wearable devices are used to acquire the WiFi strength signals of the surrounding Wireless Access Points used to build an ensemble of Machine Learning classification algorithms. Once built, the ensemble algorithm is used to locate a user based on the WiFi strength signals provided by the wearable device. Experimental results for five different urban flats are reported, showing that the system is robust and reliable enough for locating a user at room level into his/her home. Another interesting characteristic of the presented system is that it does not require deployment of any infrastructure, and it is unobtrusive, the only device required for it to work is a smart-watch.

  7. An efficient multi-carrier position-based packet forwarding protocol for wireless sensor networks

    KAUST Repository

    Bader, Ahmed

    2012-01-01

    Beaconless position-based forwarding protocols have recently evolved as a promising solution for packet forwarding in wireless sensor networks. However, as the node density grows, the overhead incurred in the process of relay selection grows significantly. As such, end-to-end performance in terms of energy and latency is adversely impacted. With the motivation of developing a packet forwarding mechanism that is tolerant to variation in node density, an alternative position-based protocol is proposed in this paper. In contrast to existing beaconless protocols, the proposed protocol is designed such that it eliminates the need for potential relays to undergo a relay selection process. Rather, any eligible relay may decide to forward the packet ahead, thus significantly reducing the underlying overhead. The operation of the proposed protocol is empowered by exploiting favorable features of orthogonal frequency division multiplexing (OFDM) at the physical layer. The end-to-end performance of the proposed protocol is evaluated against existing beaconless position-based protocols analytically and as well by means of simulations. The proposed protocol is demonstrated in this paper to be more efficient. In particular, it is shown that for the same amount of energy the proposed protocol transports one bit from source to destination much quicker. © 2012 IEEE.

  8. A RSSI-based parameter tracking strategy for constrained position localization

    Science.gov (United States)

    Du, Jinze; Diouris, Jean-François; Wang, Yide

    2017-12-01

    In this paper, a received signal strength indicator (RSSI)-based parameter tracking strategy for constrained position localization is proposed. To estimate channel model parameters, least mean squares method (LMS) is associated with the trilateration method. In the context of applications where the positions are constrained on a grid, a novel tracking strategy is proposed to determine the real position and obtain the actual parameters in the monitored region. Based on practical data acquired from a real localization system, an experimental channel model is constructed to provide RSSI values and verify the proposed tracking strategy. Quantitative criteria are given to guarantee the efficiency of the proposed tracking strategy by providing a trade-off between the grid resolution and parameter variation. The simulation results show a good behavior of the proposed tracking strategy in the presence of space-time variation of the propagation channel. Compared with the existing RSSI-based algorithms, the proposed tracking strategy exhibits better localization accuracy but consumes more calculation time. In addition, a tracking test is performed to validate the effectiveness of the proposed tracking strategy.

  9. Computerized detection method for asymptomatic white matter lesions in brain screening MR images using a clustering technique

    International Nuclear Information System (INIS)

    Kunieda, Takuya; Uchiyama, Yoshikazu; Hara, Takeshi

    2008-01-01

    Asymptomatic white matter lesions are frequently identified by the screening system known as Brain Dock, which is intended for the detection of asymptomatic brain diseases. The detection of asymptomatic white matter lesions is important because their presence is associated with an increased risk of stroke. Therefore, we have developed a computerized method for the detection of asymptomatic white matter lesions in order to assist radiologists in image interpretation as a ''second opinion''. Our database consisted of T 1 - and T 2 -weighted images obtained from 73 patients. The locations of the white matter lesions were determined by an experienced neuroradiologist. In order to restrict the area to be searched for white matter lesions, we first segmented the cerebral region in T 1 -weighted images by applying thresholding and region-growing techniques. To identify the initial candidate lesions, k-means clustering with pixel values in T 1 - and T 2 -weighted images was applied to the segmented cerebral region. To eliminate false positives (FPs), we determined the features, such as location, size, and circularity, of each of the initial candidate lesions. Finally, a rule-based scheme and a quadratic discriminant analysis with these features were employed to distinguish between white matter lesions and FPs. The results showed that the sensitivity for the detection of white matter lesions was 93.2%, with 4.3 FPs per image, suggesting that our computerized method may be useful for the detection of asymptomatic white matter lesions in T 1 - and T 2 -weighted images. (author)

  10. Performance of positive ion based high power ion source of EAST neutral beam injector

    International Nuclear Information System (INIS)

    Hu, Chundong; Xie, Yahong; Xie, Yuanlai; Liu, Sheng; Xu, Yongjian; Liang, Lizhen; Jiang, Caichao; Li, Jun; Liu, Zhimin

    2016-01-01

    The positive ion based source with a hot cathode based arc chamber and a tetrode accelerator was employed for a neutral beam injector on the experimental advanced superconducting tokamak (EAST). Four ion sources were developed and each ion source has produced 4 MW @ 80 keV hydrogen beam on the test bed. 100 s long pulse operation with modulated beam has also been tested on the test bed. The accelerator was upgraded from circular shaped to diamond shaped in the latest two ion sources. In the latest campaign of EAST experiment, four ion sources injected more than 4 MW deuterium beam with beam energy of 60 keV into EAST

  11. Assessing the efficiency of different CSO positions based on network graph characteristics.

    Science.gov (United States)

    Sitzenfrei, R; Urich, C; Möderl, M; Rauch, W

    2013-01-01

    The technical design of urban drainage systems comprises two major aspects: first, the spatial layout of the sewer system and second, the pipe-sizing process. Usually, engineers determine the spatial layout of the sewer network manually, taking into account physical features and future planning scenarios. Before the pipe-sizing process starts, it is important to determine locations of possible weirs and combined sewer overflows (CSOs) based on, e.g. distance to receiving water bodies or to a wastewater treatment plant and available space for storage units. However, positions of CSOs are also determined by topological characteristics of the sewer networks. In order to better understand the impact of placement choices for CSOs and storage units in new systems, this work aims to determine case unspecific, general rules. Therefore, based on numerous, stochastically generated virtual alpine sewer systems of different sizes it is investigated how choices for placement of CSOs and storage units have an impact on the pipe-sizing process (hence, also on investment costs) and on technical performance (CSO efficiency and flooding). To describe the impact of the topological positions of these elements in the sewer networks, graph characteristics are used. With an evaluation of 2,000 different alpine combined sewer systems, it was found that, as expected, with CSOs at more downstream positions in the network, greater construction costs and better performance regarding CSO efficiency result. At a specific point (i.e. topological network position), no significant difference (further increase) in construction costs can be identified. Contrarily, the flooding efficiency increases with more upstream positions of the CSOs. Therefore, CSO and flooding efficiency are in a trade-off conflict and a compromise is required.

  12. Parallel effects of processing fluency and positive affect on familiarity-based recognition decisions for faces

    Directory of Open Access Journals (Sweden)

    Devin eDuke

    2014-04-01

    Full Text Available According to attribution models of familiarity assessment, people can use a heuristic in recognition-memory decisions, in which they attribute the subjective ease of processing of a memory probe to a prior encounter with the stimulus in question. Research in social cognition suggests that experienced positive affect may be the proximal cue that signals fluency in various experimental contexts. In the present study, we compared the effects of positive affect and fluency on recognition-memory judgments for faces with neutral emotional expression. We predicted that if positive affect is indeed the critical cue that signals processing fluency at retrieval, then its manipulation should produce effects that closely mirror those produced by manipulations of processing fluency. In two experiments, we employed a masked-priming procedure in combination with a Remember-Know paradigm that aimed to separate familiarity- from recollection-based memory decisions. In addition, participants performed a prime-discrimination task that allowed us to take inter-individual differences in prime awareness into account. We found highly similar effects of our priming manipulations of processing fluency and of positive affect. In both cases, the critical effect was specific to familiarity-based recognition responses. Moreover, in both experiments it was reflected in a shift towards a more liberal response bias, rather than in changed discrimination. Finally, in both experiments, the effect was found to be related to prime awareness; it was present only in participants who reported a lack of such awareness on the prime-discrimination task. These findings add to a growing body of evidence that points not only to a role of fluency, but also of positive affect in familiarity assessment. As such they are consistent with the idea that fluency itself may be hedonically marked.

  13. Parallel effects of processing fluency and positive affect on familiarity-based recognition decisions for faces.

    Science.gov (United States)

    Duke, Devin; Fiacconi, Chris M; Köhler, Stefan

    2014-01-01

    According to attribution models of familiarity assessment, people can use a heuristic in recognition-memory decisions, in which they attribute the subjective ease of processing of a memory probe to a prior encounter with the stimulus in question. Research in social cognition suggests that experienced positive affect may be the proximal cue that signals fluency in various experimental contexts. In the present study, we compared the effects of positive affect and fluency on recognition-memory judgments for faces with neutral emotional expression. We predicted that if positive affect is indeed the critical cue that signals processing fluency at retrieval, then its manipulation should produce effects that closely mirror those produced by manipulations of processing fluency. In two experiments, we employed a masked-priming procedure in combination with a Remember-Know (RK) paradigm that aimed to separate familiarity- from recollection-based memory decisions. In addition, participants performed a prime-discrimination task that allowed us to take inter-individual differences in prime awareness into account. We found highly similar effects of our priming manipulations of processing fluency and of positive affect. In both cases, the critical effect was specific to familiarity-based recognition responses. Moreover, in both experiments it was reflected in a shift toward a more liberal response bias, rather than in changed discrimination. Finally, in both experiments, the effect was found to be related to prime awareness; it was present only in participants who reported a lack of such awareness on the prime-discrimination task. These findings add to a growing body of evidence that points not only to a role of fluency, but also of positive affect in familiarity assessment. As such they are consistent with the idea that fluency itself may be hedonically marked.

  14. The Small Breathing Amplitude at the Upper Lobes Favors the Attraction of Polymorphonuclear Neutrophils to Mycobacterium tuberculosis Lesions and Helps to Understand the Evolution toward Active Disease in An Individual-Based Model.

    Science.gov (United States)

    Cardona, Pere-Joan; Prats, Clara

    2016-01-01

    Infection with Mycobacterium tuberculosis (Mtb) can induce two kinds of lesions, namely proliferative and exudative. The former are based on the presence of macrophages with controlled induction of intragranulomatous necrosis, and are even able to stop its physical progression, thus avoiding the induction of active tuberculosis (TB). In contrast, the most significant characteristic of exudative lesions is their massive infiltration with polymorphonuclear neutrophils (PMNs), which favor enlargement of the lesions and extracellular growth of the bacilli. We have built an individual-based model (IBM) (known as "TBPATCH") using the NetLogo interface to better understand the progression from Mtb infection to TB. We have tested four main factors previously identified as being able to favor the infiltration of Mtb-infected lesions with PMNs, namely the tolerability of infected macrophages to the bacillary load; the capacity to modulate the Th17 response; the breathing amplitude (BAM) (large or small in the lower and upper lobes respectively), which influences bacillary drainage at the alveoli; and the encapsulation of Mtb-infected lesions by the interlobular septae that structure the pulmonary parenchyma into secondary lobes. Overall, although all the factors analyzed play some role, the small BAM is the major factor determining whether Mtb-infected lesions become exudative, and thus induce TB, thereby helping to understand why this usually takes place in the upper lobes. This information will be very useful for the design of future prophylactic and therapeutic approaches against TB.

  15. Occurrence and severity of enamel decalcification adjacent to bracket bases and sub-bracket lesions during orthodontic treatment with two different lingual appliances

    Science.gov (United States)

    Klang, Elisabeth; Helms, Hans-Joachim; Wiechmann, Dirk

    2016-01-01

    Summary Background: Using lingual enamel surfaces for bracket placement not only has esthetic advantages, but may also be suitable in terms of reducing frequencies of enamel decalcifications. Objective: To test the null-hypothesis that there is no significant difference in enamel decalcification or cavitation incidence adjacent to and beneath bracket bases between two lingual multi-bracket (MB) appliances that are different in terms of design, material composition, and manufacturing technology (group A: WIN, DW-LingualSystems; group B: Incognito, 3M-Unitek), taking into account patient- and treatment-related variables on white spot lesion (WSL) formation. Methods: Standardized, digital, top-view photographs of 630 consecutive subjects (16214 teeth; n Incognito = 237/6076 teeth; n WIN = 393/10138 teeth; mean age: 17.47±7.8; m/f 43.2/56.8%) with completed lingual MB treatment of the upper and lower permanent teeth 1–7 were screened for decalcification or cavitation adjacent to and beneath the bracket bases before and after treatment, scored from 0 to 7. Non-parametric ANOVA was used for main effects ‘appliance type’, ‘gender’, ‘treatment complexity’, ‘grouped age’ (≤16/>16 years), and ‘treatment duration’ as covariable, at an α-level of 5%. Results: About 2.57% [5.94%] of all teeth in group A [B] developed decalcifications. Subject-related incidence was 9.59% [16.17%] for upper incisors in group A [B], and 12.98% [25.74%] for all teeth 16–46. There were significant effects by gender, age, and treatment duration. Conclusion: The null-hypothesis was rejected: sub-bracket lesions were significantly less frequent in group A, while frequencies of WSL adjacent to brackets were not significantly affected by appliance type. In view of the overall low incidences of lingual post-orthodontic white-spot lesions, the use of lingual appliances is advocated as a valid strategy for a reduction of enamel decalcifications during orthodontic treatment. PMID

  16. Association of physical examination knee effusion with bone marrow lesions: cross-sectional and longitudinal analyses of a population-based cohort.

    Science.gov (United States)

    Cibere, Jolanda; Guermazi, Ali; Nicolaou, Savvas; Esdaile, John M; Thorne, Anona; Singer, Joel; Wong, Hubert; Kopec, Jacek A; Sayre, Eric C

    2018-04-12

    To determine the association of physical examination (PE) effusion with prevalence of bone marrow lesions (BML) on MRI, and incidence/progression of BML over 3 years in knee osteoarthritis (OA). A population-based cohort with knee pain (N=255) was assessed for PE effusion. On MRI, BML was graded 0-3 (none, mild, moderate, severe), incidence/progression defined as a worsening in the sum of BML scores over six surfaces by ≥1 grade. We analyzed the full cohort and mild disease subsample with Kellgren-Lawrence (KL) grade value (PPV) and negative predictive value (NPV) for PE effusion vs. BML (prevalence and incidence/progression). Weighted mean age was 56.7 years, mean BMI 26.5, 56.3% were female, 20.1% had PE effusion and 80.7% had KLrecruitment into clinical trials. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. MRI of the stener lesion

    International Nuclear Information System (INIS)

    Haramati, N.; Hiller, N.; Dowdle, J.; Jacobson, M.; Barax, C.N.; Lieberfarb, R.I.; Lester, B.; Kulick, R.G.

    1995-01-01

    Six cadaver thumbs had ulnar collateral ligament (UCL) tears created surgically. MR examinations (2D STIR and 3D GRASS) were performed identically on all specimens both before displacement (non-Stener) and after displacement (Stener lesion) of the UCL. The MR images were then randomly numbered. Each image was evaluated separately in blinded fashion by four musculoskeletal radiologists for the presence or absence of a Stener lesion. Each radiologist reinterpreted the images after an interval of several days. The interpretation was based on previously published criteria for Stener lesion diagnosis by MR. The sensitivity of GRASS ranged from 0.17 to 0.67 with the most experienced reader scoring the lowest. The specificity of GRASS ranged from 0.33 to 1.0 (most experienced reader 0.67, 0.83). STIR had a sensitivity of 0.00-0.17 and a specificity of 0.53-0.83. The K values for inter- and intraobserver agreement were measured. The intraobserver K for GRASS was 0.27-0.75 (most experienced reader 0.75). 2D imaging is probably inadequate for the evaluation of Stener lesions. The most likely reason is that the STIR slice thickness of 3 mm limits resolution of small UCLs. The poor sensitivity and specificity of GRASS as well as poor interobserver agreement suggest that MR may not be sufficiently accurate for Stener lesion evaluation. (orig./MG)

  18. A HISTOPATHOLOGICAL SPECTRUM OF NECK LESIONS IN A RURAL HOSPITAL

    Directory of Open Access Journals (Sweden)

    Shri Lakshmi Surapaneni

    2016-07-01

    Full Text Available BACKGROUND A multitude of lesions occur in the neck and patients come to hospital on account of morbidity associated with these lesions. Therefore a histopathological study of the spectrum of neck lesions was undertaken. MATERIALS AND METHODS All histologically diagnosed lesions of the neck from January 2014 to December 2015 were noted. Details of gender, age, location and diagnosis were recorded. The lesions were classified based on anatomic location, gross and histological features and clinically. Clinically, lesions were classified as congenital, inflammatory/infective and neoplastic. Incidence of age, gender and location of different lesions was calculated using percentage, and median. The findings were compared with other studies. RESULTS A total of 140 neck lesions were included in the current study. Neck lesions were predominant in females with 94 cases. The median age group involved was the 21-30 group. Anterior neck lesions were more common. Anterior midline lesions were 74 and mostly thyroid and thyroglossal duct origin. Lesions of the lymph node were greater in the posterior triangle. 122 lesions were solid and 18 were cystic. Histologically, there were 64 thyroid gland lesions, 40 lymph node lesions, 13 soft tissue tumours, 8 salivary lesions, 10 thyroglossal cysts and 5 skin/adnexal lesions. Clinically, congenital/developmental lesions were 11, inflammatory/infective lesions were 68 and neoplastic lesions were 61. Of the neoplastic lesions, 17 were malignant. CONCLUSION Non-neoplastic lesions of the neck were common in our study in accordance with findings in other studies. The most common malignancy was Papillary carcinoma of thyroid.

  19. A Police and Insurance Joint Management System Based on High Precision BDS/GPS Positioning

    Science.gov (United States)

    Zuo, Wenwei; Guo, Chi; Liu, Jingnan; Peng, Xuan; Yang, Min

    2018-01-01

    Car ownership in China reached 194 million vehicles at the end of 2016. The traffic congestion index (TCI) exceeds 2.0 during rush hour in some cities. Inefficient processing for minor traffic accidents is considered to be one of the leading causes for road traffic jams. Meanwhile, the process after an accident is quite troublesome. The main reason is that it is almost always impossible to get the complete chain of evidence when the accident happens. Accordingly, a police and insurance joint management system is developed which is based on high precision BeiDou Navigation Satellite System (BDS)/Global Positioning System (GPS) positioning to process traffic accidents. First of all, an intelligent vehicle rearview mirror terminal is developed. The terminal applies a commonly used consumer electronic device with single frequency navigation. Based on the high precision BDS/GPS positioning algorithm, its accuracy can reach sub-meter level in the urban areas. More specifically, a kernel driver is built to realize the high precision positioning algorithm in an Android HAL layer. Thus the third-party application developers can call the general location Application Programming Interface (API) of the original standard Global Navigation Satellite System (GNSS) to get high precision positioning results. Therefore, the terminal can provide lane level positioning service for car users. Next, a remote traffic accident processing platform is built to provide big data analysis and management. According to the big data analysis of information collected by BDS high precision intelligent sense service, vehicle behaviors can be obtained. The platform can also automatically match and screen the data that uploads after an accident to achieve accurate reproduction of the scene. Thus, it helps traffic police and insurance personnel to complete remote responsibility identification and survey for the accident. Thirdly, a rapid processing flow is established in this article to meet the